774 research outputs found
Effect of pancreatic extract on insulin secreting cell differentiation from mouse bone marrow mesenchymal stem cells
زمینه و هدف: با دیابت نوع یک در نتیجه ی تخریب خود ایمنی سلول های بتای جزایر پانکراس ایجاد می شود. مطالعات اخیر نشان میدهد بسیاری از انواع سلول های بنیادی می توانند به عنوان منابع احتمالی برای به دست آوردن سلول های قابل پیوند تولید کننده انسولین (IPCs) در نظر گرفته شوند. در این مطالعه تمایز سلول های بنیادی مزانشیمی مغز استخوان به سلول های مولد انسولین با استفاده از عصاره پانکراس موش مورد بررسی قرار گرفت. روش بررسی: در این مطالعه تجربی آزمایشگاهی از سلول های بنیادی مزانشیمی مغز استخوان موش کوچک آزمایشگاهی برای تمایز به سلول های انسولین ساز استفاده شد. سلول های تمایز یافته با استفاده از رنگ اختصاصی دیتیزون و آنتی بادی های ضد انسولین- پروانسولین و ضد رسپتور بتای انسولین مورد ارزیابی قرار گرفتند. همچنین بیان ژن اختصاصی سلول های پانکراسی یعنی pdx-I در این سلول ها با روش RT-PCR بررسی شد. یافته ها: سلول های تمایز یافته مشتق از روش مستقیم مورفولوژی مشابه با سلول های بتای پانکراس نشان دادند. سلول های دیتیزون مثبت به صورت دستجات قرمز ارغوانی دیده شدند. نتایج بررسی RT-PCR بیان ژن اختصاصی سلول های بتا (pdx-I) را در سلول های تمایز مستقیم نشان داد. ایمنوفلورسنس وجود نشانگرهای اختصاصی سلول های بتا را دراین سلول ها به اثبات رساند. نتیجه گیری: نتایج این مطالعه نشان داد که سلول های بنیادی مزانشیمی مغز استخوان می توانند در حضور عصاره پانکراس به سلول های مولد انسولین تمایز یابند؛ لذا استفاده از این نتایج تولید سلول های بتا از سلول های بنیادی در شرایط آزمایشگاهی را تسهیل می کند
The fluctuations of physicochemical factors and phytoplankton populations of Urmia Lake, Iran
Urmia Lake is one of the two large hypersaline lakes in the world which have Artemia. It is located in northwest of Iran. Due to a decrease in water inflow and volume, the salinity of Urmia Lake has reached to more than 300 g.l-1 since 2001. The increased salinity has greatly influenced biological aspects of the lake, and caused the lake undergoes at critical conduction. The aim of the present study was to investigate the distribution fluctuations of phytoplanktons and selected physicochemical factors in relation to Artemia distribution in Urmia Lake during 8 months. Statistical analysis of mean values of ion concentrations and phytoplankton abundance indicated significant differences among sampling months. The minimum and maximum values for the selected factors were, as Cl- 176.2-201.3 g.l-1 , CO2 95-175mg.l-1 , dissolved oxygen (DO) 0.1-2.8 mg.l-1 , HCO3 - 144-496 mg.l-1 , PO42+ 104-875 mg.l-1, NO3- 330-4104 mg.l-1, NO2- 4-21.5 mg.l-1, SO42- 10490-29840 mg.l-1, Ca2+ 561-1606 mg.l-1, Mg2+ 3649-14587 mg.l-1 while water hardness was 21000- 62000 mg.l-1. Fourteen phytoplankton genera included Bacillariophyceae (10 genera),Chlorophyceae (2 genera) and Cyanophyceae (2 genera) were identified during sampling period. The smallest average density of phytoplankton 97249 L-1 was observed in December 2005 and the greatest average density 481983 L-1 in August 2005. Dunaliella sp. composed 92.1% of the lake's phytoplankton. Statistical analysis of phytoplanktons fluctuations showed a significant difference among different months (p< 0.05)
Ground state study of simple atoms within a nano-scale box
Ground state energies for confined hydrogen (H) and helium (He) atoms, inside
a penetrable/impenetrable compartment have been calculated using Diffusion
Monte Carlo (DMC) method. Specifically, we have investigated spherical and
ellipsoidal encompassing compartments of a few nanometer size. The potential is
held fixed at a constant value on the surface of the compartment and beyond.
The dependence of ground state energy on the geometrical characteristics of the
compartment as well as the potential value on its surface has been thoroughly
explored. In addition, we have investigated the cases where the nucleus
location is off the geometrical centre of the compartment.Comment: 9 pages, 5 eps figures, Revte
Development of the Nebraska Department of Transportation Winter Severity Index
Adverse weather conditions are responsible for millions of vehicular crashes, thousands of vehicular deaths and billions of dollars in economic and congestion costs. Many transportation agencies utilize a performance or mobility metric to assess how well they are maintaining road access. This research focuses on the development of a winter severity index for the State of Nebraska (NEWINS). NEWINS is an event-driven index that was derived for the Nebraska Department of Transportation (NDOT) and its districts across the state. The NEWINS framework includes a categorical storm classification framework and climatological aspect to capture atmospheric conditions more accurately across the diverse spatial regions of Nebraska.
A ten-year (2006-2016) winter season database of meteorological variables for Nebraska was obtained from the National Centers for Environmental Information. Meteorological parameters were grouped into categories that subsequently provided a storm classification database. The NEWINS is based on a weighted linear combination to the collected database to measure severity statewide and across NDOT individual districts. The NEWINS results were compared to other meteorological variables, many used in other agencies’ winter severity indices. This comparison verified the NEWINS robustness for the observed events for the ten year period. For example, an assessment of the difference between days with observed snowfall versus days with accumulated snowfall revealed a 39% average reduction in days. Furthermore, the NEWINS results highlight the greater number of events during the 2009-2010 winter season, and the lack of events during the 2011-2012 drought year. The NEWINS also shows strong differences monthly and among NDOT districts across the state with a general decrease in events from the western to eastern NDOT districts. In addition, NEWINS storm classifications were compared to NDOT winter maintenance operations performance data for a sample winter season. Last, the 2016-17 winter season was computed to provide a testbed for the NEWINS procedure. It is expected that the NEWINS could help transportation personnel to efficiently allocate resources during adverse weather events, while balancing safety, mobility, and available budget. Further, the theoretical and practical contributions provided by the NEWINS can be used by other agencies to assess their weather sensitivity
Development of the Nebraska Department of Transportation Winter Severity Index
Adverse weather conditions are responsible for millions of vehicular crashes, thousands of vehicular deaths and billions of dollars in economic and congestion costs. Many transportation agencies utilize a performance or mobility metric to assess how well they are maintaining road access. This research focuses on the development of a winter severity index for the State of Nebraska (NEWINS). NEWINS is an event-driven index that was derived for the Nebraska Department of Transportation (NDOT) and its districts across the state. The NEWINS framework includes a categorical storm classification framework and climatological aspect to capture atmospheric conditions more accurately across the diverse spatial regions of Nebraska.
A ten-year (2006-2016) winter season database of meteorological variables for Nebraska was obtained from the National Centers for Environmental Information. Meteorological parameters were grouped into categories that subsequently provided a storm classification database. The NEWINS is based on a weighted linear combination to the collected database to measure severity statewide and across NDOT individual districts. The NEWINS results were compared to other meteorological variables, many used in other agencies’ winter severity indices. This comparison verified the NEWINS robustness for the observed events for the ten year period. For example, an assessment of the difference between days with observed snowfall versus days with accumulated snowfall revealed a 39% average reduction in days. Furthermore, the NEWINS results highlight the greater number of events during the 2009-2010 winter season, and the lack of events during the 2011-2012 drought year. The NEWINS also shows strong differences monthly and among NDOT districts across the state with a general decrease in events from the western to eastern NDOT districts. In addition, NEWINS storm classifications were compared to NDOT winter maintenance operations performance data for a sample winter season. Last, the 2016-17 winter season was computed to provide a testbed for the NEWINS procedure. It is expected that the NEWINS could help transportation personnel to efficiently allocate resources during adverse weather events, while balancing safety, mobility, and available budget. Further, the theoretical and practical contributions provided by the NEWINS can be used by other agencies to assess their weather sensitivity
Structural morphology of Al-Mg-Si alloy friction stir welds through tool eccentricity
In this work, the microstructure development in the stir zone of Al-Mg-Si alloy is evaluated while employing tool eccentricity during friction stir welding. Low dislocation density with dispersoids were observed in the inner band region of the stir zone produced with aligned tooling. On the other hand, a high dislocation density with Mg2Si precipitates can be observed in the same region of the stir zone when a tool eccentricity of 0.2 mm was utilized. The discrepancy is attributed to the enhanced shearing activity imposed on the material during the welding process
Efficient and simple production of insulin-producing cells from embryonal carcinoma stem cells using mouse neonate pancreas extract, as a natural inducer
An attractive approach to replace the destroyed insulin-producing cells (IPCs) is the generation of functional β cells from stem cells. Embryonal carcinoma (EC) stem cells are pluripotent cells which can differentiate into all cell types. The present study was carried out to establish a simple nonselective inductive culture system for generation of IPCs from P19 EC cells by 1–2 weeks old mouse pancreas extract (MPE). Since, mouse pancreatic islets undergo further remodeling and maturation for 2–3 weeks after birth, we hypothesized that the mouse neonatal MPE contains essential factors to induce in vitro differentiation of pancreatic lineages. Pluripotency of P19 cells were first confirmed by expression analysis of stem cell markers, Oct3/4, Sox-2 and Nanog. In order to induce differentiation, the cells were cultured in a medium supplemented by different concentrations of MPE (50, 100, 200 and 300 µg/ml). The results showed that P19 cells could differentiate into IPCs and form dithizone-positive cell clusters. The generated P19-derived IPCs were immunoreactive to proinsulin, insulin and insulin receptor beta. The expression of pancreatic β cell genes including, PDX-1, INS1 and INS2 were also confirmed. The peak response at the 100 µg/ml MPE used for investigation of EP300 and CREB1 gene expression. When stimulated with glucose, these cells synthesized and secreted insulin. Network analysis of the key transcription factors (PDX-1, EP300, CREB1) during the generation of IPCs resulted in introduction of novel regulatory candidates such as MIR17, and VEZF1 transcription factors, as well as MORN1, DKFZp761P0212, and WAC proteins. Altogether, we demonstrated the possibility of generating IPCs from undifferentiated EC cells, with the characteristics of pancreatic β cells. The derivation of pancreatic cells from EC cells which are ES cell siblings would provide a valuable experimental tool in study of pancreatic development and function as well as rapid production of IPCs for transplantation.Marzieh Ebrahimie, Fariba Esmaeili, Somayeh Cheraghi, Fariba Houshmand, Leila Shabani, Esmaeil Ebrahimi
Idiopathic Perforation of the Sigmoid Colon in a 2.5 Years Old Girl: A Case Report
Idiopathic colon perforation is rare in children. It is more common at the extremes of age. Splenic flextures, ileocecal and lower sigmoid regions are the most common sites of perforation. Delay in proper management of this condition is associated with high mortality and morbidity rate. We report on the case of a 2.5 years old girl who presented with fever, diarrhea, nausea and vomiting and progressive abdominal distention.Finally, she underwent an exploratory laparotomy for suspected peritonitis because of the patient's worsening condition. An area of perforation was found in the sigmoid colon that segmental resection and an end double barrel colostomy was done
Epidemiological survey of tularemia in Ilam Province, west of Iran
Background: Francisella tularensis is the causative agent of tularemia in humans and a large number of animal species. Considering recent evidence of the circulation of this bacterium in different parts of Iran, especially in the western provinces, the aim of current study was to determine the tularemia seroprevalence in the human population living in Ilam Province. Methods: In 2015, 360 serum samples were collected from five groups of people: ranchers (n = 112), farmers (n = 79), butchers and slaughterhouse workers (n = 61), Nature Conservation Officers (n = 34), and referents of medical diagnostic laboratories (n = 74). These samples were tested for the presence of anti- F. tularensis IgG antibodies using the ELISA method. Results: According to the ELISA manufacturer cutoffs, we found that 10 (2.78) and 9 (2.5) sera, respectively, were positive or borderline for F. tularensis IgG antibodies. The highest tularemia seroprevalence was observed among farmers (7.59). Conclusions: Our results strongly support the circulation of tularemia in Ilam Province. Because no human tularemia case has been reported so far in this province, we recommend specific education programs to increase knowledge of local health care professionals about this important zoonotic disease. © 2019 The Author(s)
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