Search results for: Paraptosis-like program cell death
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 8269

Search results for: Paraptosis-like program cell death

7309 Cytotoxic Activity Of Major Iridoids From Barleria Trispinosa (Forssk.) Vahl. Growing In Saudi Arabia

Authors: Hamza Assiry, Gamal A. Mohamed, Sabrin R. M. Ibrahim, Hossam M. Abdallah

Abstract:

Chemical investigation of the aerial parts of Barleria trispinosa(Forssk.) Vahl. resulted in isolation of four major iridoids that were identified as 6,8-O,O-diacetylshanhiside methyl ester (acetyl barlerin) (1), 8-O-acetylshanzhiside methyl ester (barlerin) (2), shanzhiside methyl ester (3), and 6- ⍺ -L-rhamnopyranosyl-8-O-acetylshanzihiside methyl ester (4). The isolated compounds were confirmed by detailed one and two-dimensional NMR. Isolated compounds were tested for their cytotoxic activity on breast cancer (MCF-7, MDA-MB-231) and colon cancer (LS174T) cell linesusing sulphorhodamine B (SRB) assay. It is noteworthy that compound 1 demonstrated a significant cytotoxic potential towards MDA-MB-231 cell line with IC5016.7 ± 2.7µg / mL compared to doxorubicin whereas compounds 2, showed moderate cytotoxic potential with IC5021.2 ± 1.9µg / mL on MCF-7. The other compounds showed moderate activity on the tested cell lines.

Keywords: acanthaceae, cytotoxicity, metabolites, barleria trispinosa

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7308 Reducing The Frequency of Flooding Accompanied by Low pH Wastewater In 100/200 Unit of Phosphate Fertilizer 1 Plant by Implementing The 3R Program (Reduce, Reuse and Recycle)

Authors: Pradipta Risang Ratna Sambawa, Driya Herseta, Mahendra Fajri Nugraha

Abstract:

In 2020, PT Petrokimia Gresik implemented a program to increase the ROP (Run Of Pile) production rate at the Phosphate Fertilizer 1 plant, causing an increase in scrubbing water consumption in the 100/200 area unit. This increase in water consumption causes a higher discharge of wastewater, which can further cause local flooding, especially during the rainy season. The 100/200 area of the Phosphate Fertilizer 1 plant is close to the warehouse and is often a passing area for trucks transporting raw materials. This causes the pH in the wastewater to become acidic (the worst point is up to pH 1). The problem of flooding and exposure to acidic wastewater in the 100/200 area of Phosphate Fertilizer Plant 1 was then resolved by PT Petrokimia Gresik through wastewater optimization steps called the 3R program (Reduce, Reuse, and Recycle). The 3R (Reduce, reuse, and recycle) program consists of an air consumption reduction program by considering the liquid/gas ratio in scrubbing unit of 100/200 Phosphate Fertilizer 1 plant, creating a wastewater interconnection line so that wastewater from unit 100/200 can be used as scrubbing water in the Phonska 1, Phonska 2, Phonska 3 and unit 300 Phosphate Fertilizer 1 plant and increasing scrubbing effectiveness through scrubbing effectiveness simulations. Through a series of wastewater optimization programs, PT Petrokimia Gresik has succeeded in reducing NaOH consumption for neutralization up to 2,880 kg/day or equivalent in saving up to 314,359.76 dollars/year and reducing process water consumption up to 600 m3/day or equivalent in saving up to 63,739.62 dollars/year.

Keywords: fertilizer, phosphate fertilizer, wastewater, wastewater treatment, water management

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7307 Canine Neonatal Mortality at the São Paulo State University Veterinary Hospital, Botucatu, São Paulo, Brazil – Preliminary Data

Authors: Maria L. G. Lourenço, Keylla H. N. P. Pereira, Viviane Y. Hibaru, Fabiana F. Souza, João C. P. Ferreira, Simone B. Chiacchio, Luiz H. A. Machado

Abstract:

The neonatal mortality rates in dogs are considered high, varying between 5.7 and 21.2% around the world, and the causes of the deaths are often unknown. Data regarding canine neonatal mortality are scarce in Brazil. This study aims at describing the neonatal mortality rates in dogs, as well as the main causes of death. The study included 152 litters and 669 neonates admitted to the São Paulo State University (UNESP) Veterinary Hospital, Botucatu, São Paulo, Brazil between January 2018 and September 2019. The overall mortality rate was 16.7% (112/669), with 40% (61/152) of the litters presenting at least one case of stillbirth or neonatal mortality. The rate of stillbirths was 7.7% (51/669), while the neonatal mortality rate was 9% (61/669). The early mortality rate (0 to 2 days) was 13.7% (92/669), accounting for 82.1% (92/112) of all deaths. The late mortality rate (3 to 30 days) was 2.7% (18/669), accounting for 16% (18/112) of all deaths. Infection was the causa mortis in 51.8% (58/112) of the newborns, of which 30.3% (34/112) were caused by bacterial sepsis, and 21.4% (24/112) were caused by other bacterial, viral or parasite infections. Other causes of death included congenital malformations (15.2%, 17/112), of which 5.3% (6/112) happened through euthanasia due to malformations incompatible with life; asphyxia/hypoxia by dystocia (9.8%, 11/112); wasting syndrome in debilitated newborns (6.2%, 7/112); aspiration pneumonia (3.6%, 4/112); agalactia (2.7%, 3/112); trauma (1.8%, 2/112); administration of contraceptives to the mother (1.8%, 2/112) and unknown causes (7.1%, 8/112). The neonatal mortality rate was considered high, but they may be even higher in locations without adequate care for the mothers and neonates. Therefore, prenatal examinations and early neonatal care are of utmost importance for the survival of these patients.

Keywords: neonate dogs, puppies, mortality rate, neonatal death

Procedia PDF Downloads 199
7306 Contributions of Search and Rescue to the World Peace

Authors: Dursun Kalebaşi

Abstract:

When we examine the history of mankind (from the past up to the present), we see that millions of people died because of the wars. Especially, since the beginning of 19th century, the increase of the human death rate is caused mostly by the regional conflicts and natural disasters rather than the wars. From that point of view, the biggest threat humanity face today is temperature increase and climate change that started to emerge in recent years. When we take into account the natural disasters on one hand and refuges that flee from regional conflicts on the other, it stands out as a dramatic situation because of the huge human losses. In this context, most of the countries started to give more importance to Search and Rescue (SAR) operations to stop the loss of lives or decrease the death rate. This article will tell about the SAR activities in Turkey since 2000 and discuss the Turkey’s contributions to Rescue Missions after the natural disasters in different parts of the world. Moreover, there will be some new highlights to a more habitable and more peaceful world through the SAR missions.

Keywords: search and rescue, natural disasters, migration and world peace, Turkish army forces

Procedia PDF Downloads 375
7305 Treatment of NMSC with Traditional Medicine Method

Authors: Aferdita Stroka Koka, Laver Stroka, Juna Musa, Samanda Celaj

Abstract:

Non-melanoma skin cancers (NMSCs) are the most common human malignancies. About 5.4 million basal and squamous cell skin cancers are diagnosed each year in the US and new cases continue to grow. About eight out of ten of these are basal cell cancers. Squamous cell cancers occur less often. NMSC usually are treatable, but treatment is expensive and can leave scars. In 2019, 167 patients of both sexes suffering from NMSC were treated by traditional medicine. Patients who have been diagnosed with Basal Cell Carcinoma were 122 cases, Squamous Cell Carcinoma 32 cases and both of them 13 cases. Of these,122 cases were ulcerated lesions and 45 unulcerated lesions. All patients were treated with the herbal solution called NILS, which contains extracts of some Albanian plants such as Allium sativum, Jugulans regia and Laurus nobilis. The treatment is done locally, on the surface of the tumor, applying the solution until the tumor mass is destroyed and, after that, giving the necessary time to the wound to make the regeneration that coincides with the complete healing of the wound. We have prepared a collection of photos for each case. Since the first sessions, a shrinkage and reduction of the tumor mass were evident, up to the total disappearance of the lesion at the end of treatment. The normal period of treatment lasted 1 to 2 weeks, depending on the size of the tumor, then take care of it until the closure of the wound, taking the whole process from 1 to 3 months. In 7 patients, the lesion failed to be dominated by treatment and they underwent standard treatment with radiotherapy or surgery, while in 10 patients, the lesion recurred and was treated again. The aim of this survey was to put in evidence the good results obtained by treatment of NMSC with Albanian traditional medicine methods.

Keywords: local treatment, nils, NMSC, traditional medicine

Procedia PDF Downloads 207
7304 Microbial Contamination of Cell Phones of Health Care Workers: Case Study in Mampong Municipal Government Hospital, Ghana

Authors: Francis Gyapong, Denis Yar

Abstract:

The use of cell phones has become an indispensable tool in the hospital's settings. Cell phones are used in hospitals without restrictions regardless of their unknown microbial load. However, the indiscriminate use of mobile devices, especially at health facilities, can act as a vehicle for transmitting pathogenic bacteria and other microorganisms. These potential pathogens become exogenous sources of infection for the patients and are also a potential health hazard for self and as well as family members. These are a growing problem in many health care institutions. Innovations in mobile communication have led to better patient care in diabetes, asthma, and increased in vaccine uptake via SMS. Notwithstanding, the use of cell phones can be a great potential source for nosocomial infections. Many studies reported heavy microbial contamination of cell phones among healthcare workers and communities. However, limited studies have been reported in our region on bacterial contamination on cell phones among healthcare workers. This study assessed microbial contamination of cell phones of health care workers (HCWs) at the Mampong Municipal Government Hospital (MMGH), Ghana. A cross-sectional design was used to characterize bacterial microflora on cell phones of HCWs at the MMGH. A total of thirty-five (35) swab samples of cell phones of HCWs at the Laboratory, Dental Unit, Children’s Ward, Theater and Male ward were randomly collected for laboratory examinations. A suspension of the swab samples was each streak on blood and MacConkey agar and incubated at 37℃ for 48 hours. Bacterial isolates were identified using appropriate laboratory and biochemical tests. Kirby-Bauer disc diffusion method was used to determine the antimicrobial sensitivity tests of the isolates. Data analysis was performed using SPSS version 16. All mobile phones sampled were contaminated with one or more bacterial isolates. Cell phones from the Male ward, Dental Unit, Laboratory, Theatre and Children’s ward had at least three different bacterial isolates; 85.7%, 71.4%, 57.1% and 28.6% for both Theater and Children’s ward respectively. Bacterial contaminants identified were Staphylococcus epidermidis (37%), Staphylococcus aureus (26%), E. coli (20%), Bacillus spp. (11%) and Klebsiella spp. (6 %). Except for the Children ward, E. coli was isolated at all study sites and predominant (42.9%) at the Dental Unit while Klebsiella spp. (28.6%) was only isolated at the Children’s ward. Antibiotic sensitivity testing of Staphylococcus aureus indicated that they were highly sensitive to cephalexin (89%) tetracycline (80%), gentamycin (75%), lincomycin (70%), ciprofloxacin (67%) and highly resistant to ampicillin (75%). Some of these bacteria isolated are potential pathogens and their presence on cell phones of HCWs could be transmitted to patients and their families. Hence strict hand washing before and after every contact with patient and phone be enforced to reduce the risk of nosocomial infections.

Keywords: mobile phones, bacterial contamination, patients, MMGH

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7303 Comparative Outcomes of Percutaneous Coronary Intervention in Smokers versus Non Nonsmokers Patients: Observational Studies

Authors: Pratima Tatke, Archana Avhad, Bhanu Duggal, Meeta Rajivlochan, Sujata Saunik, Pradip Vyas, Nidhi Pandey, Aditee Dalvi, Jyothi Subramanian

Abstract:

Background: Smoking is well established risk factor for the development and progression of coronary artery disease. It is strongly related to morbidity and mortality from cardiovascular causes. The aim of this study is to observe effect of smoking status on percutaneous coronary intervention(PCI) after 1 year. Methods: 2527 patients who underwent PCI at different hospital of Maharashtra(India) from 2012 to 2015 under the health insurance scheme which is launched by Health department, Government of Maharashtra for below poverty line(BPL) families which covers cardiology. Informed consent of patients was taken .They were followed by telephonic survey after 6months to 1year of PCI . Outcomes of interest included myocardial infarction, restenosis, cardiac rehospitalization, death, and a composite of events after PCI. Made group of two non smokers-1861 and smokers (including patients who quit at time of PCI )-659. Results: Statistical Analysis using Pearson’s chi square test revealed that there was trend seen of increasing incidence of death, Myocardial infarction and Restenosis in smokers than non smokers .Smokers had a greater death risk compared to nonsmoker; 5.7% and 5.1% respectively p=0.518. Also Repeat procedures (2.1% vs. 1.5% p=0.222), breathlessness (17.8% vs. 18.20% p=0.1) and Myocardial Infarction (7.3% vs. 10%) high in smoker than non smokers. Conclusion: Major adverse cardiovascular events (MACE) were observed even after successful PCI in smokers. Patients undergoing percutaneous coronary intervention should be encouraged to stop smoking.

Keywords: coronary artery diseases, major adverse cardiovascular events, percutaneous coronary intervention, smoking

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7302 Molecular Docking of Marrubiin in Candida Rugosa Lipase

Authors: Benarous Khedidja, Yousfi Mohamed

Abstract:

Infections caused by Candida species manifest in a number of diseases, including candidemia, vulvovaginal candidiasis, endocarditis, and peritonitis. These Candida species have been reported to have lipolytic activity by secretion of lipolytic enzymes such as esterases, lipases and phospholipases. These Extracellular hydrolytic enzymes seem to play an important role in Candida overgrowth. Candidiasis is commonly treated with antimycotics such as clotrimazole and nystatin, which bind to a major component of the fungal cell membrane (ergosterol). This binding forms pores in the membrane that lead to death of the fungus. Due to their secondary effects, scientists have thought of another treatment basing on lipase inhibition but we haven’t found any lipase inhibitors used as candidiasis treatment. In this work, we are interested to lipases inhibitors such as alkaloids as another candidiasis treatment. In the first part, we have proceeded to optimize the alkaloid structures and protein 3D structure using Hyperchem software. Secondly, we have docked inhibitors using Genetic algorithm with GOLD software. The results have shown ten possibilities of binding inhibitor to Candida rugosa lipase (CRL) but only one possibility has been accepted depending on the weakest binding energy.

Keywords: marrubiin, candida rugosa lipase, docking, gold

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7301 Application of Thermoplastic Microbioreactor to the Single Cell Study of Budding Yeast to Decipher the Effect of 5-Hydroxymethylfurfural on Growth

Authors: Elif Gencturk, Ekin Yurdakul, Ahmet Y. Celik, Senol Mutlu, Kutlu O. Ulgen

Abstract:

Yeast cells are generally used as a model system of eukaryotes due to their complex genetic structure, rapid growth ability in optimum conditions, easy replication and well-defined genetic system properties. Thus, yeast cells increased the knowledge of the principal pathways in humans. During fermentation, carbohydrates (hexoses and pentoses) degrade into some toxic by-products such as 5-hydroxymethylfurfural (5-HMF or HMF) and furfural. HMF influences the ethanol yield, and ethanol productivity; it interferes with microbial growth and is considered as a potent inhibitor of bioethanol production. In this study, yeast single cell behavior under HMF application was monitored by using a continuous flow single phase microfluidic platform. Microfluidic device in operation is fabricated by hot embossing and thermo-compression techniques from cyclo-olefin polymer (COP). COP is biocompatible, transparent and rigid material and it is suitable for observing fluorescence of cells considering its low auto-fluorescence characteristic. The response of yeast cells was recorded through Red Fluorescent Protein (RFP) tagged Nop56 gene product, which is an essential evolutionary-conserved nucleolar protein, and also a member of the box C/D snoRNP complexes. With the application of HMF, yeast cell proliferation continued but HMF slowed down the cell growth, and after HMF treatment the cell proliferation stopped. By the addition of fresh nutrient medium, the yeast cells recovered after 6 hours of HMF exposure. Thus, HMF application suppresses normal functioning of cell cycle but it does not cause cells to die. The monitoring of Nop56 expression phases of the individual cells shed light on the protein and ribosome synthesis cycles along with their link to growth. Further computational study revealed that the mechanisms underlying the inhibitory or inductive effects of HMF on growth are enriched in functional categories of protein degradation, protein processing, DNA repair and multidrug resistance. The present microfluidic device can successfully be used for studying the effects of inhibitory agents on growth by single cell tracking, thus capturing cell to cell variations. By metabolic engineering techniques, engineered strains can be developed, and the metabolic network of the microorganism can thus be manipulated such that chemical overproduction of target metabolite is achieved along with the maximum growth/biomass yield.  

Keywords: COP, HMF, ribosome biogenesis, thermoplastic microbioreactor, yeast

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7300 The Effect of Manual Acupuncture-induced Injury as a Mechanism Contributing to Muscle Regeneration

Authors: Kamal Ameis

Abstract:

This study aims to further improve our understanding of the underlying mechanism of local injury that occurs after manual acupuncture needle manipulation, and that initiates the muscle regeneration process, which is essential for muscle maintenance and adaptation. Skeletal muscle is maintained by resident stem cells called muscle satellite cells. These cells are normally in quiescent state, but following muscle injury, they re-enter the cell cycle and execute a myogenic program resulting in muscle fiber regeneration. Our previous work in young rats demonstrated that acupuncture treatment induced injury that activated resident satellite (stem) cells, which leads to muscle regeneration. Skeletal muscle regeneration is an adaptive response to injury that requires a tightly orchestrated event between signaling pathways activated by growth factor and intrinsic regulatory program controlled by myogenic transcription factor. We identified several gene expressions uniquely important for muscle regeneration in response to acupuncture treatment at different time course using different biological techniques, including Immunocytochemistry, western blotting, and Real Time PCR. This study uses a novel but non-invasive model of injury induced by manual acupuncture to further our current understanding of regenerative mechanism of muscle stem cells. From a clinical perspective, this model of injury induced by manual acupuncture may be easily translatable into a clinical tool that can be used as an alternative to physical exercise for patients challenged by bed rest or forced inactivity. Finally, the knowledge gained from this research could be useful for studies of the local effects of various modalities of induced injury, such as the traditional method of healing by cupping (hijamah), which may enhanced muscle stem cells and muscle fiber regeneration.

Keywords: acupuncture, injury, regeneration, muscle stem cells

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7299 Evaluation of Associated Risk Factors and Determinants of near Miss Obstetric Cases at B.P. Koirala Institute of Health Sciences, Dharan

Authors: Madan Khadka, Dhruba Uprety, Rubina Rai

Abstract:

Background and objective: In 2011, around 273,465 women died worldwide during pregnancy, childbirth or within 42 days after childbirth. Near-miss is recognized as the predictor of the level of care and maternal death. The objective of the study was to evaluate the associated risk factors of near-miss obstetric cases and maternal death. Material and Methods A Prospective Observational Study was done from August 1, 2014, to June 30, 2015, in Department of Obstetrics and Gynecology at BPKIHS hospital, tertiary care hospital in Eastern Nepal, Dharan. Case eligible by the 5-factor scoring system and WHO near miss criteria were evaluated. Risk factors included severe hemorrhage, hypertensive disorders, and a complication of abortion, ruptured uterus, medical/surgical condition and sepsis. Results: A total of 9,727 delivery were attended during the study period from August 2014 to June 2014. There were 6307 (71.5%) vaginal delivery and 2777(28.5%) caesarean section and 181 perinatal death with a total of 9,546 live birth. A total of 162 near miss was identified, and 16 maternal death occurred during the study. Maternal near miss rate of 16.6 per 1000 live birth, Women with life-threatening conditions (WLTC) of 172, Severe maternal outcome ratio of 18.64 per 1000 live birth, Maternal near-miss mortality ratio (MNM: 1 MD) 10.1:1, Mortality index (MI) of 8.98%. Risk factors were obstetric hemorrhage 27.8%, abortion/ectopic 27.2%, eclampsia 16%, medical/surgical condition 14.8%, sepsis 13.6%, severe preeclamsia 11.1%, ruptured uterus 3.1%, and molar pregnancy 1.9%. 19.75% were prim gravidae, with mean age 25.66 yrs, and cardiovascular and coagulation dysfunction as a major life threatening condition and sepsis (25%) was the major cause of mortality. Conclusion: Hemorrhage and hypertensive disorders are the leading causes of near miss event and sepsis as a leading cause of mortality. As near miss analysis indicates the quality of health care, it is worth presenting in national indices.

Keywords: abortion, eclampsia, hemorrhage, maternal mortility, near miss

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7298 Literature Review of Empirical Studies on the Psychological Processes of End-of-Life Cancer Patients

Authors: Kimiyo Shimomai, Mihoko Harada

Abstract:

This study is a literature review of the psychological reactions that occur in end-of-life cancer patients who are nearing death. It searched electronic databases and selected literature related to psychological studies of end-of-life patients. There was no limit on the search period, and the search was conducted until the second week of December 2021. The keywords were specified as “death and dying”, “terminal illness”, “end-of-life”, “palliative care”, “psycho-oncology” and “research”. These literatures referred to Holly (2017): Comprehensive Systematic Review for Advanced Practice Nursing, P268 Figure 10.3 to ensure quality. These literatures were selected with a dissertation score of 4 or 5. The review was conducted in two stages with reference to the procedure of George (2002). First, these references were searched for keywords in the database, and then relevant references were selected from the psychology and nursing studies of end-of-life patients. The number of literatures analyzed was 76 for overseas and 17 for domestic. As for the independent variables, "physical variable" was the most common in 36 literatures (66.7%), followed by "psychological variable" in 35 literatures (64.8%), "spiritual variable" in 21 literatures (38%), and "social variable" in 17 literatures. (31.5%), "Variables related to medical care / treatment" were 16 literatures (29.6%). To summarize the relationship between these independent variables and the dependent variable, when the dependent variable is "psychological variable", the independent variables are "psychological variable", "social variable", and "physical variable". Among the independent variables, the physical variables were the most common. The psychological responses that occur in end-stage cancer patients who are nearing death are mutually influenced by psychological, social, and physical variables. Therefore, it supported the "total pain" advocated by Cicely Saunders.

Keywords: cancer patient, end-of-life, literature review, psychological process

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7297 Modeling Pronunciations of Arab Broca’s Aphasics Using Mosstalk Words Technique

Authors: Sadeq Al Yaari, Fayza Alhammadi, Ayman Al Yaari, Montaha Al Yaari, Aayah Al Yaari, Adham Al Yaari, Sajedah Al Yaari, Saleh Al Yami

Abstract:

Background: There has been a debate in the literature over the years as to whether or not MossTalk Words program fits Arab Broca’s aphasics (BAs) due to that language differences and also the fact that the technique has not yet been used for aphasics with semantic dementia (SD aphasics). Aims: To oversimplify the above mentioned debate slightly for purposes of exposition, the purpose of the present study is to investigate the “usability” of this program as well as pictures and community as therapeutic techniques for both Arab BAs and SD aphasics. Method: The subjects of this study are two Saudi aphasics (53 and 57 years old, respectively). The former suffers from Broca’s aphasia due to a stroke, while the latter suffers from semantic dementia. Both aphasics can speak English and have used the Moss Talk Words program in addition to intensive picture-naming therapeutic sessions for two years. They were tested by one of the researchers four times (a time per six months). The families of the two subjects, in addition to their relatives and friends, played a major part in all therapeutic sessions. Conclusion: Results show that in averages across the entire therapeutic sessions, MossTalk Words program was clearly found more effective in modeling BAs’ pronunciation than that of SD aphasic. Furthermore, picture-naming intensive exercises in addition to the positive role of the community members played a major role in the progress of the two subjects’ performance.

Keywords: moss talk words, program, technique, Broca’s aphasia, semantic dementia, subjects, picture, community

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7296 IEP Curriculum to Include For-Credit University English Classes

Authors: Cheyne Kirkpatrick

Abstract:

In an attempt to make the university intensive English program more worthwhile for students, many English language programs are redesigning curriculum to offer for-credit English for Academic Purposes classes, sometimes marketed as “bridge” courses. These programs are designed to be accredited to national language standards, provide communicative language learning, and give students the opportunity to simultaneously earn university language credit while becoming proficient in academic English. This presentation will discuss the curriculum design of one such program in the United States at a large private university that created its own for-credit “bridge” program. The planning, development, piloting, teaching, and challenges of designing this type of curriculum will be presented along with the aspects of accreditation, communicative language learning, and integration within various university programs. Attendees will learn about how such programs are created and what types of objectives and outcomes are included in American EAP classes.

Keywords: IEP, AEP, Curriculum, CEFR, University Credit, Bridge

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7295 The Study of Self-Management of Stress (SMS) of Yoga Program for Pregnant Women in Early Pregnancy in Taiwan

Authors: Shau-Ping Shiu, Shu-Ling Lin

Abstract:

Pregnancy lead a process of changing in the endocrine system. Either pregnancy itself or the surrounding affect such as the attitude of family to the pregnant lady can bring lots of stress. Sever stress may lead pregnant women display serious mental problem such as mood swings, impulsivity, and abnormal behavior. A method of self management of stress(SMS) has been proved that help patient of cancer in release their stress. This study were going to use SMS to help pregnant women. Methods: In this study, 42 ladies in the first to third months of pregnancy process applied to join SMS of program have divided into 21 participants in both control and experimental group by draw. 24 sessions of Yoga program were conducted once a week for 6 months for experimental group. Verbatim used to gather more feedbacks from the interview followed by each Yoga sessions. Brief symptom Rating scale also conducted pre and post experiment for 42 participations. Results: Overall score of Brief Symptom Rating Scale reduced 17.82 points and suicide drop 9 points in experimental group, compared to the control group increasing 10.24 point of overall score and suicide add 7 points. Feedback from interviews showed participations improved in emotion, physical health and stress management. They indicated having more positive emotion daily, having better gastrointestinal peristalsis movement, releasing back tention, well weight control, reducing stress and changing the quality of interpersonal relationships. Conclusion: SMS of Yoga program in this study included four key training directions which were stimulation, relaxation, awareness and pranayama lead a great improvment of stress management for pregnant lady. Throughout this Yoga program, women learned to ignite eustress, remove distress, create calmness and breath slows down. As the result, Yoga program has helped women in experiment group lower their tension, and bring the extra benifits in emotion and relationships. It support women to overcome their pregnancy. Suggestion: An unexpected result of this study showed all participants had no morning sickness since they engaged in SMS program, and no one absent from course due to the benefits of it. We strongly suggest that SMS of Yoga program can be a add of medication for women in pregnancy, however, the position of Forward in the SMS sequence has been point out pressing participant’s stomach, which can be replace to Bridge position to comfort participants.

Keywords: self-management of stress(SMS), yoga program, pregnant women, early pregnancy

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7294 Adaptation and Validation of the Program Sustainability Assessment Tool

Authors: Henok Metaferia Gebremariam

Abstract:

Worldwide, considerable resources are spent implementing public health interventions that are interrupted soon after the initial funding ends. However, ambiguity remains as to how health programs can be effectively sustained over time because of the diversity of perspectives, definitions, study methods, outcomes measures and timeframes. From all the above-mentioned research challenges, standardized measures of sustainability should ultimately become a key research issue. To resolve this key challenge, the objective of the study was to adapt a tool for measuring the program’s capacity for sustainability and evaluating its reliability and validity. To adapt and validate the tool, a cross-sectional and cohort study design was conducted at 26 programs in Addis Ababa between September 2014 and May 2015. An adapted version of the tool after the pilot test was administered to 220 staff. The tool was analyzed for reliability and validity. Results show that a 40-item PSAT tool had been adapted into the Amharic version with good internal consistency (Cronbach’s alpha= 0.80), test-retest reliability(r=0.916) and construct validity. Factor analysis resulted in 7 components explaining 56.67 % of the variance. In conclusion, it was found that the Amharic version of PAST was a reliable and valid tool for measuring the program’s capacity for sustainability.

Keywords: program sustainability, public health interventions, reliability, validity

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7293 Human TP53 Three Dimentional (3D) Core Domain Hot Spot Mutations at Codon, 36, 72 and 240 are Associated with Oral Squamous Cell Carcinoma

Authors: Saima Saleem, Zubair Abbasi, Abdul Hameed, Mansoor Ahmed Khan, Navid Rashid Qureshi, Abid Azhar

Abstract:

Oral Squamous Cell Carcinoma (OSCC) is the leading cause of death in the developing countries like Pakistan. This problem aggravates because of the excessive use of available chewing products. In spite of widespread information on their use and purported legislations against their use the Pakistani markets are classical examples of selling chewable carcinogenic mutagens. Reported studies indicated that these products are rich in reactive oxygen species (ROS) and polyphenols. TP53 gene is involved in the suppression of tumor. It has been reported that somatic mutations caused by TP53 gene are the foundation of the cancer. This study aims to find the loss of TP53 functions due to mutation/polymorphism caused by genomic alteration and interaction with tobacco and its related ingredients. Total 260 tissues and blood specimens were collected from OSCC patients and compared with age and sex matched controls. Mutations in exons 2-11 of TP53 were examined by PCR-SSCP. Samples showing mobility shift were directly sequenced. Two mutations were found in exon 4 at nucleotide position 108 and 215 and one in exon 7 at nucleotide position 719 of the coding sequences in patient’s tumor samples. These results show that substitution of proline with arginine at codon 72 and serine with threonine at codon 240 of p53 protein. These polymorphic changes, found in tumor samples of OSCC, could be involved in loss of heterozygocity and apoptotic activity in the binding domain of TP53. The model of the mutated TP53 gene elaborated a nonfunctional unfolded p53 protein, suggesting an important role of these mutations in p53 protein inactivation and malfunction. This nonfunctional 3D model also indicates that exogenous tobacco related carcinogens may act as DNA-damaging agents affecting the structure of DNA. The interpretations could be helpful in establishing the pathways responsible for tumor formation in OSCC patients.

Keywords: TP53 mutation/polymorphism, OSCC, PCR-SSCP, direct DNA sequencing, 3D structure

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7292 System Analysis of Quality Assurance in Online Education

Authors: Keh-Wen Carin Chuang, Kuan-Chou Chen

Abstract:

Our society is in a constant state of change. Technology advancements continue to affect our daily lives. How we work, communicate and entertain ourselves has changed dramatically in the past decades. As our society learns to accept and adapt to the many different technological advances that seem to inundate every part of our lives, the education institutions must migrate from traditional methods of instruction to online education in order to take full advantage of the opportunities provided by these technology advancements. There are many benefits that can be gained for university and society from offering online programs by utilizing advanced technologies. But the programs must not be implemented carelessly. The key to providing a quality online program is the issue of perceived quality, which takes into account the viewpoint of all stakeholders involved. To truly ensure the institutional quality, however, a systemic view of all factors contributing to the quality must be analyzed and linked to one another — allowing education administrators to understand how each factor contributes to the perceived quality of online education. The perceived quality of an online program will be positively reinforced only through an organizational-wide effort that focuses on managed administration, augmenting online program branding, skilled faculty, supportive alumni, student satisfaction, and effective delivery systems — each of which is vital to a quality online program. This study focuses on the concept of quality assurance in the start-up, implementation, and sustainability of online education. A case of online MBA program will be analyzed to explore the quality assurance. The difficulties in promoting online education quality is the fact that universities are complex networks of disciplinary, social, economic, and political fiefdoms, both internal and external factors to the institutions. As such, the system analysis, a systems-thinking approach, on the issue of perceived quality is ideal to investigate the factors and how each factor contributes to the perceived quality in the online education domain.

Keywords: systems thinking, quality assurance, online education, MBA program

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7291 Establishment and Characterization of a Dentigerous Cyst Cell Line

Authors: Muñiz-Lino Marcos Agustín, Vazquez Borbolla Jessica, Licéaga-Escalera Carlos

Abstract:

The ectomesenchymal tissues involved in tooth development and their remnants are the origin of different odontogenic lesions, including tumors and cysts of the jaws, with a wide range of clinical behaviors. Dentigerous cyst (DC) represents approximately 20% of all cases of odontogenic cysts, and it has been demonstrated that it can develop benign and malignant odontogenic tumors. DC is characterized by bone destruction of the area surrounding the crown of a tooth which has not erupted and it contain is liquid. The treatment of odontogenic tumors and cysts usually are partial or total removal of the jaw, causing important secondary co-morbidities. However, molecules implicated in DC pathogenesis as well in its development to odontogenic tumors remains unknown. A cellular model may be useful to study these molecules, but that model has not been established yet. Here, we reported the establishment of a cell culture derived from a dentigerous cyst. This cell line was named DeCy-1. In spite of its ectomesenchymal morphology, DeCy-1 cells express epithelial markers such as cytokeratins 5, 6, and 8. Furthermore, these cells express the ODAM protein, which is present in odontogenesis and in dental follicle, indicating that DeCy-1 cells derived from odontogenic epithelium. Analysis by electron microscopy of this cell line showed that it has a high vesicular activity, suggesting that DeCy-1 could secrete molecules that may be involved in DC pathogenesis. Thus, secreted proteins were analyzed by PAGE-SDS, where we observed approximately 11 bands. In addition, the capacity of these secretions to degrade proteins was analyzed by gelatin substrate zymography. A degradation band of about 62 kDa was found in these assays. Western blot assays suggested that the matrix metalloproteinase 2 (MMP-2) is responsible of this protease activity. Thus, our results indicate that the establishment of a cell line derived from DC is a useful in vitro model to study the biology of this odontogenic lesion and its participation in the development of odontogenic tumors.

Keywords: dentigerous cyst, MMP20, cancer, cell culture

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7290 A Case Comparative Study of Infant Mortality Rate in North-West Nigeria

Authors: G. I. Onwuka, A. Danbaba, S. U. Gulumbe

Abstract:

This study investigated of Infant Mortality Rate as observed at a general hospital in Kaduna-South, Kaduna State, North West Nigeria. The causes of infant Mortality were examined. The data used for this analysis were collected at the statistics unit of the Hospital. The analysis was carried out on the data using Multiple Linear regression Technique and this showed that there is linear relationship between the dependent variable (death) and the independent variables (malaria, measles, anaemia, and coronary heart disease). The resultant model also revealed that a unit increment in each of these diseases would result to a unit increment in death recorded, 98.7% of the total variation in mortality is explained by the given model. The highest number of mortality was recorded in July, 2005 and the lowest mortality recorded in October, 2009.Recommendations were however made based on the results of the study.

Keywords: infant mortality rate, multiple linear regression, diseases, serial correlation

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7289 High Efficiency Achievement by a New Heterojunction N-Zno:Al/P-Si Solar Cell

Authors: A. Bouloufa, F. Khaled, K. Djessas

Abstract:

This paper presents a new structure of solar cell based on p-type microcrystalline silicon as an absorber and n-type aluminum doped zinc oxide (ZnO:Al) transparent conductive oxide as an optical window. The ZnO:Al layer deposited by rf-magnetron sputtering at room temperature yields a low resistivity about 7,64.10-2Ω.cm and more than 85% mean optical transmittance in the VIS–NIR range, with an optical band gap of 3.3 eV. These excellent optical properties of this layer in combination with an optimal contact at the front surface result in a superior light trapping yielding to efficiencies about 20%. In order to improve efficiency, we have used a p+-µc-Si thin layer highly doped as a back surface field which minimizes significantly the impact of rear surface recombination velocity on voltage and current leading to a high efficiency of 24%. Optoelectronic parameters were determined using the current density-voltage (J-V) curve by means of a numerical simulation with Analysis of Microelectronic and Photonic Structures (AMPS-1D) device simulator.

Keywords: optical window, thin film, solar cell, efficiency

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7288 The Effect of Training Program by Using Especial Strength on the Performance Skills of Hockey Players

Authors: Wesam El Bana

Abstract:

The current research aimed at designing a training program for improving specific muscular strength through using the especial strength and identifying its effects on the performance level skills of hockey players. The researcher used the quasi-experimental approach (two – group design) with pre- and post-measurements. Sample: (n= 35) was purposefully chosen from sharkia sports club. Five hockey player were excluded due to their non-punctuality. The rest were divided into two equal groups (experimental and control). The researcher concluded the following: The traditional training program had a positive effect on improving the physical variables under investigation as it led to increasing the improvement percentages of the physical variables and the performance level skills of the control group between the pre- and post-measurement. The recommended training program had a positive effect on improving the physical variables under investigation as it led to increasing the improvement percentages of the physical variable and the performance level skills of the experimental group between the pre- and post-measurements. Exercises using the especial strength training had a positive effect on the post-measurement of the experimental group.

Keywords: hockey, especial strength, performance skills

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7287 Developing an Intervention Program to Promote Healthy Eating in a Catering System Based on Qualitative Research Results

Authors: O. Katz-Shufan, T. Simon-Tuval, L. Sabag, L. Granek, D. R. Shahar

Abstract:

Meals provided at catering systems are a common source of workers' nutrition and were found as contributing high amounts calories and fat. Thus, eating daily catering food can lead to overweight and chronic diseases. On the other hand, the institutional dining room may be an ideal environment for implementation of intervention programs that promote healthy eating. This may improve diners' lifestyle and reduce their prevalence of overweight, obesity and chronic diseases. The significance of this study is in developing an intervention program based on the diners’ dietary habits, preferences and their attitudes towards various intervention programs. In addition, a successful catering-based intervention program may have a significant effect simultaneously on a large group of diners, leading to improved nutrition, healthier lifestyle, and disease-prevention on a large scale. In order to develop the intervention program, we conducted a qualitative study. We interviewed 13 diners who eat regularly at catering systems, using a semi-structured interview. The interviews were recorded, transcribed and then analyzed by the thematic method, which identifies, analyzes and reports themes within the data. The interviews revealed several major themes, including expectation of diners to be provided with healthy food choices; their request for nutrition-expert involvement in planning the meals; the diners' feel that there is a conflict between sensory attractiveness of the food and its' nutritional quality. In the context of the catering-based intervention programs, the diners prefer scientific and clear messages focusing on labeling healthy dishes only, as opposed to the labeling of unhealthy dishes; they were interested in a nutritional education program to accompany the intervention program. Based on these findings, we have developed an intervention program that includes: changes in food served such as replacing several menu items and nutritional improvement of some of the recipes; as well as, environmental changes such as changing the location of some food items presented on the buffet, placing positive nutritional labels on healthy dishes and an ongoing healthy nutrition campaign, all accompanied by a nutrition education program. The intervention program is currently being tested for its impact on health outcomes and its cost-effectiveness.

Keywords: catering system, food services, intervention, nutrition policy, public health, qualitative research

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7286 Effect of Surfactant Level of Microemulsions and Nanoemulsions on Cell Viability

Authors: Sonal Gupta, Rakhi Bansal, Javed Ali, Reema Gabrani, Shweta Dang

Abstract:

Nanoemulsions (NEs) and microemulsions (MEs) have been an attractive tool for encapsulation of both hydrophilic and lipophillic actives. Both these systems are composed of oil phase, surfactant, co-surfactant and aqueous phase. Depending upon the application and intended use, both oil-in-water and water-in-oil emulsions can be designed. NEs are fabricated using high energy methods employing less percentage of surfactant as compared to MEs which are self assembled drug delivery systems. Owing to the nanometric size of the droplets these systems have been widely used to enhance solubility and bioavailability of natural as well as synthetic molecules. The aim of the present study is to assess the effect of % age of surfactants on cell viability of Vero cells (African Green Monkeys’ Kidney epithelial cells) via MTT assay. Green tea catechin (Polyphenon 60) loaded ME employing low energy vortexing and NE employing high energy ultrasonication were prepared using same excipients (labrasol as oil, cremophor EL as surfactant and glycerol as co-surfactant) however, the % age of oil and surfactant needed to prepare the ME was higher as compared to NE. These formulations along with their excipients (oilME=13.3%, SmixME=26.67%; oilNE=10%, SmixNE=13.52%) were added to Vero cells for 24 hrs. The tetrazolium dye, 3-(4,5-dimethylthia/ol-2-yl)-2,5-diphi-iiyltclrazolium bromide (MTT), is reduced by live cells and this reaction is used as the end point to evaluate the cytoxicity level of a test formulation. Results of MTT assay indicated that oil at different percentages exhibited almost equal cell viability (oilME ≅ oilNE) while surfactant mixture had a significant difference in the cell viability values (SmixME < SmixNE). Polyphenon 60 loaded ME and its PlaceboME showed higher toxicity as compared to Polyphenon 60 loaded NE and its PlaceboNE that can be attributed to the higher concentration of surfactants present in MEs. Another probable reason for high % cell viability of Polyphenon 60 loaded NE might be due to the effective release of Polyphenon 60 from NE formulation that helps in the sustenance of Vero cells.

Keywords: cell viability, microemulsion, MTT, nanoemulsion, surfactants, ultrasonication

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7285 Aerobic Capacity Outcomes after an Aerobic Exercise Program with an Upper Body Ergometer in Diabetic Amputees

Authors: Cecilia Estela Jiménez Pérez Campos

Abstract:

Introduction: Amputation comes from a series of complications in diabetic persons; at that point, of the illness evolution they have a deplored aerobic capacity. Adding to that, cardiac rehabs programs are almost base in several activities in a standing position. The cardiac rehabilitation programs have to improve for them, based on scientific advice. Objective: Evaluation of aerobic capacity of diabetic amputee after an aerobic exercise program, with upper limb ergometer. Methodology: The design is longitudinal, prospective, comparative and no randomized. We include all diabetic pelvic limb amputees, who assist to the cardiac rehabilitation. We made 2 groups: an experimental and a control group. The patients did the exercise testing, with the author’s design protocol. The experimental group completed 24 exercise sessions (3 sessions/week), with an intensity determined with the training heart rate. At the end of 8 weeks period, the subjects did a second exercise test. Results: Both groups were a homogeneous sample in age (experimental n=15) 57.6+12.5 years old and (control n=8) 52.5+8.0 years old, sex, occupation, education and economic features. (square chi) (p=0.28). The initial aerobic capacity was similar in both groups. And the aerobic capacity accomplishes after the program was statistically greater in the experimental group than in the control one. The final media VO2peak (mlO2/kg/min) was experimental (17.1+3.8), control (10.5+3.8), p=0.001. (t student). Conclusions: The aerobic capacity improved after an arm ergometer exercise program and the quality of life improve too, in diabetic amputees. So this program is fundamental in diabetic amputee’s rehabilitation management.

Keywords: aerobic fitness, metabolic equivalent (MET), oxygen output, upper limb ergometer

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7284 Teacher Trainers’ Motivation in Transformation of Teaching and Learning: The Fun Way Approach

Authors: Malathi Balakrishnan, Gananthan M. Nadarajah, Noraini Abd Rahim, Amy Wong On Mei

Abstract:

The purpose of the study is to investigate the level of intrinsic motivation of trainers after attending a Continuous Professional Development Course (CPD) organized by Institute of Teacher Training Malaysia titled, ‘Transformation of Teaching and Learning the Fun Way’. This study employed a survey whereby 96 teacher trainers were given Situational Intrinsic Motivational Scale (SIMS) Instruments. Confirmatory factor analysis was carried out to get validity of this instrument in local setting. Data were analyzed with SPSS for descriptive statistic. Semi structured interviews were also administrated to collect qualitative data on participants experiences after participating in the two-day fun-filled program. The findings showed that the participants’ level of intrinsic motivation showed higher mean than the amotivation. The results revealed that the intrinsic motivation mean is 19.0 followed by Identified regulation with a mean of 17.4, external regulation 9.7 and amotivation 6.9. The interview data also revealed that the participants were motivated after attending this training program. It can be concluded that this program, which was organized by Institute of Teacher Training Malaysia, was able to enhance participants’ level of motivation. Self-Determination Theory (SDT) as a multidimensional approach to motivation was utilized. Therefore, teacher trainers may have more success using the ‘The fun way approach’ in conducting training program in future.

Keywords: teaching and learning, motivation, teacher trainer, SDT

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7283 Health Care Providers' Perceptions on mHealth Workplace Nutrition Wellness Program: A Thematic Analysis

Authors: Kim H. K. Choy, Oliva H. K. Chu, W. Y. Keung, B. Lim, Winnie P. Y. Tang

Abstract:

Background: Health care providers have been identified as an at-risk group for obesity. Mobile health technology can be used to motivate lifestyle behavioral changes. The aim of this study was to investigate hospital-based health care providers’ perceptions of mHealth Workplace Nutrition Wellness Program. Methods: This qualitative study was conducted at a regional hospital in Hong Kong. Ten health care providers were purposively selected for the study. Qualitative data was collected by individual face-to-face semi-structured interviews which were audio-taped, transcribed verbatim and analyzed by thematic analysis. Results: Four themes were identified: (1) mobile health technology motivates lifestyle changes, (2) self-perceived body weight initiates health behavioral changes, (3) organizational support promotes healthy behavior, (4) lack of self-confidence hinders lifestyle modification. The health care providers’ perceptions of mobile health technology, barriers, and facilitators to participation in the mHealth Workplace Nutrition Wellness Program were discussed in the study. Conclusions: Barriers, facilitators, self-perceived body weight and experiences of mobile health technology were associated with intention of participation in mHealth Workplace Nutrition Wellness Program. The knowledge generated from the study could be used to guide the design and implementation of effective interventions, strategies and policies of workplace wellness programs to promote participation for hospital’s employees.

Keywords: workplace wellness program, mobile health, barriers, facilitators, qualitative

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7282 Usage of Cord Blood Stem Cells of Asphyxia Infants for Treatment

Authors: Ahmad Shah Farhat

Abstract:

Background: Prenatal asphyxia or birth asphyxia is the medical situation resulting from a newborn infant that lasts long enough during the birth process to cause physical harm, usually to the brain. Human umbilical cord blood (UCB) is a well-established source of hematopoietic stem/progenitor cells (HSPCs) for allogeneic stem cell transplantation. These can be used clinically to care for children with malignant diseases. Low O2 can cause in proliferation and differentiation of stem cells. Method: the cord blood of 11 infants with 3-5 Apgar scores or need to cardiac pulmonary Resuscitation as an asphyxia group and ten normal infants with more than 8 Apgar scores as the normal group was collected, and after isolating hematopoietic stem cells, the cells were cultured in enriched media for 14 days to compare the numbers of colonies by microscope. Results: There was a significant difference in the number of RBC precursor colonies (red colonies) in cultured media with 107 cord blood hematopoietic stem cells of infants who were exposed to hypoxemia in two wells of palate. There was not a significant difference in the number of white cell colonies in the two groups in the two wells of the plate. Conclusion: Hypoxia in the perinatal period can cause the increase of hematopoietic stem cells of cord blood, special red precursor stem cells in vitro, like an increase of red blood cells in the body when exposed to low oxygen conditions. Thus, it will be usable.

Keywords: asphyxia, neonre, stem cell, red cell

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7281 Ageing Gingiva: A New Hope for Autologous Stem Cell Therapy

Authors: Ankush M. Dewle, Suditi Bhattacharya, Prachi R. Abhang, Savita Datar, Ajay J. Jog, Rupesh K. Srivastava, Geetanjali Tomar

Abstract:

Objectives: The aim of this study was to investigate the quality of mesenchymal stem cells (MSCs) obtained from ageing gingival tissues, in order to suggest their potential role in autologous stem cell therapy for old individuals. Methods: MSCs were isolated from gingival tissues of young (18-45 years) and old (above 45 years) donors by enzymatic digestion. MSCs were analysed for cfu-f, surface marker expression by flow-cytometry and multilineage differentiation potential. The angiogenic potential was compared in a chick embryo yolk sac membrane model. The aging and differentiation markers including SA-β-galactosidase and p21 respectively were analysed by staining and flow-cytometry analysis. Additionally, osteogenic markers such as glucocorticoid receptor (GR), vitamin D receptor (VDR) were measured by flow-cytometry and RT-qPCR was performed for quantification of osteogenic gene expression. Alizarin Red S and alkaline phosphatase (ALP) activity were also quantitated. Results: Gingival MSCs (GMSCs) from both the age groups were similar in their morphology and displayed cfu-f. They had similar expression of MSC surface markers and p21, comparable rate of proliferation and differentiated to all the four lineages. GMSCs from young donors had a higher adipogenic differentiation potential as compared to the old GMSCs. Moreover, these cells did not display a significant difference in ALP activity probably due to comparable expression of GR, VDR, and osteogenic genes. Conclusions: Ageing of GMSCs occurs at a much slower rate than stem cells from other sources. Thus we suggest GMSCs as an excellent candidate for autologous stem cell therapy in degenerative diseases of elderly individuals. Clinical Significance: GMSCs could help overcome the setbacks in clinical implementation of autologous stem cell therapy for regenerative medicine in all age group of patient.

Keywords: bone regeneration, cell therapy, senescence, stem cell

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7280 Influence of Substitution on Structure of Tin Lantanium Pyrochlore La₂₋ₓSrₓSn₂O₇₋δ(0 ≤ x ≤ 0.25) Solid-Oxide Fuel Cells

Authors: Bounar Nedjemeddine

Abstract:

Materials with the pyrochlore lattice structure have attracted much recent attention due to their wide applications in ceramic thermal barrier coatings, high-permittivity dielectrics, and potential solid electrolytes in solid-oxide fuel cells. The work described in this paper is devoted to the synthesis and characterization of a pyrochlore structure based on lanthanum (La₂O₃) and tin (SnO₂) oxides of general formula La₂Sn₂O₇, substituted by Sr at the site La. Their structures were determined from X-ray powder diffraction using CELFER analysis. All the compositions present the space group Fd-3m. The substitution of La by Sr in the La₂Sn₂O₇ compound causes a variation of the cell parameters. The difference in charge between La³⁺ and Sr²⁺ and the difference in size cause the cell parameters to decrease from a=10.7165 A° to a=10.6848 A° for the substitution rates (x = 0.05, 0.1, 0.15 ...), which leads to a decrease in the volume of the mesh. For a substitution rate x = 0.25, there is an increase in the cell parameters (a=10.7035A°), which can be explained by a competitiveness of the size effect and the presence of a gap in the structure which go in the opposite direction.

Keywords: solid-oxide fuel cells, structure, pyrochlore, X-ray diffraction

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