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21.
Muhammad Furqan Bari Martin O. Weickert Kavitha Sivakumar Sean G. James David R. J. Snead Bee Kang Tan Harpal Singh Randeva Claire Cecile Bastie Manu Vatish 《PloS one》2014,9(7)
Recently soluble CD163 (sCD163), a cleaved form of the macrophage receptor CD163, was identified as a macrophage-specific risk-predictor for developing Type 2 Diabetes. Here, we investigate circulating levels of sCD163 in gestational diabetes mellitus (GDM). Furthermore, given the role of the placenta in the pathogenesis of GDM, we assessed placental contribution to sCD163 secretion. Paired maternal (venous) and umbilical vein blood samples from GDM (n = 18) and Body Mass Index (BMI) matched control women (n = 20) delivered by caesarean section at 39–40 week gestation were assessed for circulating levels of sCD163, Tumour necrosis factor alpha (TNF-α) and Interleukin 6 (IL-6). Media from explant culture of maternal subcutaneous fat and corresponding placental tissues were assayed for these same molecules. CD163 positive cell numbers were determined in placental and adipose tissues of GDM and control women. We found significantly elevated circulating sCD163 levels in GDM mothers (688.4±46.9 ng/ml vs. 505.6±38.6 ng/ml) and their offspring (418.2±26.6 ng/ml vs. 336.3±24.4 ng/ml [p<0.05 for both]) as compared to controls, together with elevated circulating TNF-α and IL-6 levels. Moreover, both GDM placentae (268.1±10.8 ng/ml/mg vs. 187.6±20.6 ng/ml/mg) and adipose explants (41.1±2.7 ng/ml/mg vs. 26.6±2.4 ng/ml/mg) released significantly more sCD163 than controls. Lastly, significantly more CD163 positive cells were observed in GDM placentae (25.7±1.1 vs. 22.1±1.2) and adipose tissue (19.1±1.1 vs 12.7±0.9) compared to controls. We describe elevated sCD163 levels in GDM and identify human placenta as a novel source of sCD163 suggesting that placental tissues might contribute to the increased levels of circulating sCD163 in GDM pregnancies. 相似文献
22.
Muhammad A.H. Gali David I. de Pomerai 《Differentiation; research in biological diversity》1984,25(1-3):238-246
Abstract. Three different culture media, Ham's F-12, medium 199, and Eagle's minimal essential medium (MEM), were compared with respect to the expression of neuronal (choline acetyl transferase activity: CAT) and glial (hydrocortisone-induced glutamine synthetase activity; GSase) markers of normal differentiation in cultures of 9-day chick embryo neuroretinal cells, and also with respect to the accumulation of a lens marker (δ crystallin) during so-called 'transdifferentiation' in these cultures.
MEM allows transient expression of both CAT and GSase activities in early cultures, but also permits extensive δ crystallin accumulation at later stages. F-12 medium gives somewhat higher levels of CAT and GSase activities, the former being noticeably prolonged as compared with parallel MEM cultures; δ crystallin accumulation, however, is largely inhibited in F-12 cultures. By contrast, medium 199 permits only low levels of CAT and GSase activities, perhaps because the neuronal cells are distributed individually over the glial cell sheet in 199 cultures, rather than forming aggregates as in MEM or F–12 cultures. Medium 199 also blocks δ crystallin accumulation.
The results of medium changeover between 'transdifferentiation'-permissive (MEM) and non-permissive (199, F-12) conditions suggest: (a) that potential lens precursor cells (whatever their nature) survive in F-12 medium for prolonged periods without extensive expression of the lens phenotype; (b) that such precursor cells become committed to subsequent differentiation as lens cells between 10 and 20 days of culture in permissive MEM medium (as judged by the accumulation of δ crystallin following transfer into F-12); and (c) that medium 199 can block expression of the lens phenotype even in cells already committed (by the above criteria) to lens differentiation, as for instance after 30 days of preculture in MEM. 相似文献
MEM allows transient expression of both CAT and GSase activities in early cultures, but also permits extensive δ crystallin accumulation at later stages. F-12 medium gives somewhat higher levels of CAT and GSase activities, the former being noticeably prolonged as compared with parallel MEM cultures; δ crystallin accumulation, however, is largely inhibited in F-12 cultures. By contrast, medium 199 permits only low levels of CAT and GSase activities, perhaps because the neuronal cells are distributed individually over the glial cell sheet in 199 cultures, rather than forming aggregates as in MEM or F–12 cultures. Medium 199 also blocks δ crystallin accumulation.
The results of medium changeover between 'transdifferentiation'-permissive (MEM) and non-permissive (199, F-12) conditions suggest: (a) that potential lens precursor cells (whatever their nature) survive in F-12 medium for prolonged periods without extensive expression of the lens phenotype; (b) that such precursor cells become committed to subsequent differentiation as lens cells between 10 and 20 days of culture in permissive MEM medium (as judged by the accumulation of δ crystallin following transfer into F-12); and (c) that medium 199 can block expression of the lens phenotype even in cells already committed (by the above criteria) to lens differentiation, as for instance after 30 days of preculture in MEM. 相似文献
23.
Natascha Verhagen Andy Wiranata Wijaya Attila Teleki Muhammad Fadhlullah Andreas Unsld Martin Schilling Christoph Heinrich Ralf Takors 《Engineering in Life Science》2020,20(9-10):384-394
Increasing markets for biopharmaceuticals, including monoclonal antibodies, have triggered a permanent need for bioprocess optimization. Biochemical engineering approaches often include the optimization of basal and feed media to improve productivities of Chinese hamster ovary (CHO) cell cultures. Often, l ‐tyrosine is added as dipeptide to deal with its poor solubility at neutral pH. Showcasing IgG1 production with CHO cells, we investigated the supplementation of three l ‐tyrosine (TYR, Y) containing dipeptides: glycyl‐l ‐tyrosine (GY), l ‐tyrosyl‐l ‐valine (YV), and l ‐prolyl‐l ‐tyrosine (PY). While GY and YV led to almost no phenotypic and metabolic differences compared to reference samples, PY significantly amplified TYR uptake thus maximizing related catabolic activity. Consequently, ATP formation was roughly four times higher upon PY application than in reference samples. 相似文献
24.
Asghar Zeeshan Ali Nasir Waqas Muhammad Nazeer Mubbashar Khan Waqar Azeem 《Biomechanics and modeling in mechanobiology》2020,19(6):2271-2284
Biomechanics and Modeling in Mechanobiology - Every group of microorganism utilizes a diverse mechanical strategy to propel through complex environments. These swimming problems deal with the... 相似文献
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26.
Perveen Sumera Khan Tehmina Ahsan Shaheen Humaira Naz Rabia Hyder Muhammad Zeeshan Ijaz Bushra Naqvi S. M. Saqlan Yasmin Tayyaba 《In vitro cellular & developmental biology. Plant》2021,57(6):907-922
In Vitro Cellular & Developmental Biology - Plant - The OsRGLP1 gene was overexpressed under the control of CaMV 35S promoter in tomato (Solanum lycopersicum L.) plants using... 相似文献
27.
Muhammad Masroor Alam Adnan Khurshid Shahzad Shaukat Muhammad Suleman Rana Salmaan Sharif Mehar Angez Nadia Nisar Muhammad Naeem Syed Sohail Zahoor Zaidi 《PloS one》2013,8(11)
Human parechoviruses are known to cause asymptomatic to severe clinical illness predominantly respiratory and gastroenetric infections. Despite their global prevalence, epidemiological studies have not been performed in Pakistan. In this study, we retrospectively analyzed 110 fecal specimen and found 26 (24%) positive for viral RNA with HPeV-10 (n = 3, 23%), HPeV-13 (n = 4, 31%) and HPeV-15 (n = 6, 46%) genotypes. Clinical features of patients with different HPeV genotypes were compared. All HPeV positive children were aged ≤4 years (mean 13.92 months). The male-to-female ratio was 1: 1.17 (46.2 vs 53.8%) with significant association (p = .031) to HPeV infectivity. HPeV-10 and -13 were found during summer while HPeV-15 was only detected during late winter season. Disease symptoms were more severe in children infected with HPeV-10 and -13 as compared to HPeV-15. Fever and vomiting were observed in 100% cases of HPeV-10 and -13 while only 17% patients of HPeV-15 had these complaints. Phylogenetic analyses showed that HPeV-10, -13 and -15 strains found in this study have 9–13%, 16.8% and 21.8% nucleotide divergence respectively from the prototype strains and were clustered to distinct genetic lineages. This is the first report of HPeV-15 infection in humans although first identified in rhesus macaques. The arginine-glycine-aspartic acid (RGD) motif present at the C-terminal of VP1 responsible for the viral attachment to cellular integrins was not found in all of these strains. In conclusion, these findings enhance our knowledge related to the epidemiology and genetic diversity of the HPeV in Pakistan and support the need for continued laboratory based surveillance programs especially in infants and neonatal clinical settings. Further, the parechovirus pathogenesis, cross-species transmission and disease reservoirs must be ascertained to adopt better prevention measures. 相似文献
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29.
Sudeep S Gill Paula A Rochon Nathan Herrmann Philip E Lee Kathy Sykora Nadia Gunraj Sharon-Lise T Normand Jerry H Gurwitz Connie Marras Walter P Wodchis Muhammad Mamdani 《BMJ (Clinical research ed.)》2005,330(7489):445
Objective To compare the incidence of admissions to hospital for stroke among older adults with dementia receiving atypical or typical antipsychotics.Design Population based retrospective cohort study.Setting Ontario, Canada.Patients 32 710 older adults (≤ 65 years) with dementia (17 845 dispensed an atypical antipsychotic and 14 865 dispensed a typical antipsychotic).Main outcome measures Admission to hospital with the most responsible diagnosis (single most important condition responsible for the patient''s admission) of ischaemic stroke. Observation of patients until they were either admitted to hospital with ischaemic stroke, stopped taking antipsychotics, died, or the study ended.Results After adjustment for potential confounders, participants receiving atypical antipsychotics showed no significant increase in risk of ischaemic stroke compared with those receiving typical antipsychotics (adjusted hazard ratio 1.01, 95% confidence interval 0.81 to 1.26). This finding was consistent in a series of subgroup analyses, including ones of individual atypical antipsychotic drugs (risperidone, olanzapine, and quetiapine) and selected subpopulations of the main cohorts.Conclusion Older adults with dementia who take atypical antipsychotics have a similar risk of ischaemic stroke to those taking typical antipsychotics. 相似文献
30.
Two DNA fingerprinting techniques, random amplified polymorphic DNA (RAPD) and inter-retrotransposon amplified polymorphism
(IRAP), were used to characterize somaclonal variants of banana. IRAP primers were designed on the basis of repetitive and
genome-wide dispersed long terminal repeat (LTR) retrotransposon families for assessing the somaclonal variation in 2Musa clones resistant and susceptible toFusarium oxysporum f. sp.cubense race 4. RAPD markers successfully detected genetic variation within and between individuals of the clones. IRAP makers amplified
either by a single primer or a combination of primers based on LTR orientation successfully amplified different retrotransposons
dispersed in theMusa genome and detected new events of insertions. RAPD markers proved more polymorphic than IRAP markers. Somaclonal variation
seems to be the result of numerous indels occurring genome-wide accompanied by the activation of retroelements, as a result
of stress caused by micropropagation. It is concluded that characterization of the somaclonal variants requires more than
one DNA marker system to detect variation in diverse components of the genome. 相似文献