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991.
Mahrukh Ahmad Shahid Prawez Mudasir Sultana Rajinder Raina Nrip Kishore Pankaj Pawan Kumar Verma Shafiqur Rahman 《Proceedings of the National Academy of Sciences, India. Section B.》2014,84(2):397-405
Sida cordifolia is a shrub found throughout the tropical and sub-tropical plains. All parts of the plant are used as anti-rheumatic, antipyretic, anti-asthmatic, laxative, diuretic, vasorelaxative, hypotensive, central nervous system depressant, antioxidant, analgesic and hypoglycemic. The present study was aimed to evaluate the hypoglycemic, anti-hyperlipidemic and antioxidant potential of alcoholic-extract obtained from areal part of S. cordifolia in streptozotocin-induced-diabetes in wistar-rats. Diabetes was induced with streptozotocin at the intra-peritoneal dose of 55 mg/kg. Diabetic rats were treated with alcoholic extract of S. cordifolia at dosage of 200, 400 mg/kg and glibenclamide (5 mg/kg) after sub-acute administration for 28 days. Alcoholic extract of S. cordifolia at 400 mg/kg significantly improved the body-weight whereas significantly decreased the blood glucose level in diabetic rats. However at 400 mg/kg, the alcoholic extract of S. cordifolia showed beneficial effect indicating significant decrease in total cholesterol, triglycerides, low density lipids, plasma-creatinine, plasma-urea nitrogen and lipid-peroxidation and a significant increase in high density lipid-level in diabetic rats. Interestingly at 400 mg/kg, a significant increase in antioxidant enzymes such as catalase and superoxide-dismutase-activity was seen in the diabetic rats. The dose 200 mg/kg of alcoholic extract of S. cordifolia showed non-significant change in diabetic rats. The above therapeutic-potential of alcoholic extract of areal parts of plant may be because of the presence of bioactive compounds such as glycosides, resins, alkaloids, sterols, saponins and flavonoids. Thus, the findings of the present study indicate that the alcoholic extract of S. cordifolia at dosage level of 400 mg/kg produces anti-diabetic effect in the streptozotocin-induced diabetes in wistar-rats. 相似文献
992.
Roi Gazit Pankaj K. Mandal Wataru Ebina Ayal Ben-Zvi César Nombela-Arrieta Leslie E. Silberstein Derrick J. Rossi 《The Journal of experimental medicine》2014,211(7):1315-1331
Hematopoietic stem cells (HSCs) are the best-characterized tissue-specific stem cells, yet experimental study of HSCs remains challenging, as they are exceedingly rare and methods to purify them are cumbersome. Moreover, genetic tools for specifically investigating HSC biology are lacking. To address this we sought to identify genes uniquely expressed in HSCs within the hematopoietic system and to develop a reporter strain that specifically labels them. Using microarray profiling we identified several genes with HSC-restricted expression. Generation of mice with targeted reporter knock-in/knock-out alleles of one such gene, Fgd5, revealed that though Fgd5 was required for embryonic development, it was not required for definitive hematopoiesis or HSC function. Fgd5 reporter expression near exclusively labeled cells that expressed markers consistent with HSCs. Bone marrow cells isolated based solely on Fgd5 reporter signal showed potent HSC activity that was comparable to stringently purified HSCs. The labeled fraction of the Fgd5 reporter mice contained all HSC activity, and HSC-specific labeling was retained after transplantation. Derivation of next generation mice bearing an Fgd5-CreERT2 allele allowed tamoxifen-inducible deletion of a conditional allele specifically in HSCs. In summary, reporter expression from the Fgd5 locus permits identification and purification of HSCs based on single-color fluorescence.Hematopoietic stem cells (HSCs) function to maintain blood homeostasis throughout life via their unique ability to differentiate into all blood cell types and to self-renew. These properties, along with the robust ability of HSCs to engraft myeloablated recipients in the setting of BM transplantation, have established the clinical paradigm for therapeutic stem cell use (Weissman, 2000).Originally described by Till and McCulloch (1961), HSCs were first experimentally defined by their ability to form macroscopic colonies in the spleens (CFU-S) of irradiated recipients after BM transplantation that histological examination revealed contained multiple blood lineages, and cytological examination revealed were clonally derived (Becker et al., 1963). Together with the demonstration that a subset of CFU-S colonies had the potential to reform colonies when transplanted into secondary recipients (Siminovitch et al., 1963), the defining properties of hematopoietic stem cells—multipotency and self-renewal—were established. In the 50 yr since these seminal studies were conducted, the experimental study of HSCs has flourished, leading to a profound level of understanding of their biology. These efforts were enabled through the development of several in vivo and in vitro assays that permitted evaluation of HSC self-renewal and multilineage potential, and by methods that allowed purification of HSCs by FACS. HSCs were initially reported to be enriched within the Thy1lowLineage− fraction of the murine BM (Muller-Sieburg et al., 1986), and subsequently cells with a Thy1lowLineage−Sca1+ immunophenotype were shown to possess long-term multilineage repopulating activity (Spangrude et al., 1988). The immunophenotype of HSCs was further refined, culminating with the demonstration that single cells purified from the Lineage−Sca1+c-kit+ (LSK)CD34−/low fraction of the BM of adult mice could function to long-term multilineage reconstitute irradiated recipients at the clonal level (Osawa et al., 1996). Additional cell surface markers that have also been used to enrich for HSC activity include: CD105 (Chen et al., 2002), Flk2/Flt3 (Christensen and Weissman, 2001), CD201/PROCR (Balazs et al., 2006), ESAM (Ooi et al., 2009; Yokota et al., 2009), and CD150, CD48, and CD244 (Kiel et al., 2005a) among others. In addition to immunophenotype, intravital dye efflux activity has also proven to be an effective strategy for enriching for HSC activity (Bertoncello et al., 1985; Wolf et al., 1993; Goodell et al., 1996).Although immunophenotype combined with flow cytometry has become the principle technique used for identifying and studying diverse cells types, genetically engineered reporter strains have also enabled the identification and study of other cell types, including tissue-specific stem cells from other organs. For example, rapidly cycling intestinal stem cells were identified with the use of an Lgr5 reporter (Barker et al., 2007), whereas a population of more slowly cycling stem cells in the intestinal crypt were marked with a reporter for telomerase (Montgomery et al., 2011). In the developing embryo, reporter strains for Isl1 (Laugwitz et al., 2005) and WT1 (Zhou et al., 2008) have been combined with lineage-tracing experiments to identify cardiac progenitors in the developing heart. In the skin, a Tet-inducible H2B-GFP reporter stain was used in conjunction with a keratinocyte-specific driver to isolate label-retaining stem cells in the epidermis (Tumbar et al., 2004). A similar H2B-GFP label retention strategy was later used by two independent groups to explore the turnover of HSCs, showing that a label-retaining population of cells with potent HSCs activity resides in a state of prolonged dormancy during steady-state homeostasis (Wilson et al., 2008; Foudi et al., 2009). Importantly, depending on vector design, introducing reporter cassettes into specific genomic loci (knock-in) can also lead to the disruption of the targeted gene, permitting analysis of the null (knockout) genotype when targeted alleles are crossed to homozygosity.With the goals of identifying novel genes that could be used to specifically report on HSC activity within the murine BM, we performed a system-wide microarray screen of hematopoietic stem, progenitor, and effector cells, and identified a set of genes whose expression was highly restricted to the HSC compartment. Generation of mice with targeted reporter knock-in/knock-out alleles at three of the identified genes, Sult1a1, Clec1a, and Fgd5 revealed that whereas knockout of Sult1a1 and Clec1a were viable and had normal HSC function, nullizygosity of Fgd5 was embryonic lethal at midgestation, though the generation and function of definitive HSCs was not affected by loss of Fgd5. Of the three reporter alleles, only Fgd5 explicitly marked immunophenotypic HSCs in the adult marrow at steady state and after transplantation. BM cells isolated based solely on reporter signal of the Fgd5 reporter mice showed robust HSC activity, with all stem cell activity residing within the labeled fraction. These results demonstrate that HSCs can be identified and purified from the BM of Fgd5 reporter mice by single color fluorescence. Finally, the development of Fgd5-CreERT2 mice permitting inducible deletion of Floxed alleles specifically in HSCs represents an invaluable genetic resource for exploring gene function in HSC biology. 相似文献
993.
994.
Anastasios G. P. Konstas Irini C. Voudouragkaki Kostantinos G. Boboridis Anna-Bettina Haidich Eleni Paschalinou Theodoros Giannopoulos Nikolaos D. Dragoumis Alexandros K. Makridis Malik Y. Kahook 《Advances in therapy》2014,31(6):592-603
Introduction
To compare the 24-h intraocular pressure (IOP) control and tolerability of travoprost/timolol benzalkonium chloride (BAK)-free (TTFC) vs. latanoprost/timolol fixed combination preserved with BAK (LTFC) in open-angle glaucoma patients insufficiently controlled with latanoprost 0.005% monotherapy given once in the evening.Methods
The authors have conducted a prospective, observer-masked, active-controlled, cross-over, comparison study. Qualified open-angle glaucoma patients who demonstrated a latanoprost-treated morning IOP (10:00 ± 1 h) greater than 20 mmHg on two separate visits were randomized for 3 months to receive either TTFC or LTFC. Patients were then crossed over to the opposite treatment for another 3 months. At the end of the latanoprost run-in and after each 3-month therapy period patients underwent 24-h IOP monitoring in the habitual position using Goldmann applanation tonometry in the sitting position during the day (10:00, 14:00, 18:00 and 22:00) and Perkins tonometry in the supine position at night (02:00 and 06:00). Selected ocular surface parameters were evaluated after each therapy period.Results
Forty-two open-angle glaucoma patients completed the study. The mean 24-h baseline IOP on latanoprost was 21.5 ± 1.6 mmHg. Both fixed combinations significantly reduced the IOP at each time point, for the mean, peak and fluctuation of 24-h IOP compared with latanoprost monotherapy (P < 0.01). When the two fixed combinations were compared directly, TTFC provided significantly lower mean 24-h IOP (18.9 ± 2.2 mmHg) vs. LTFC (19.3 ± 2.3 mmHg) (P = 0.004) and significantly lower IOP at 18:00 (18.6 ± 2.5 vs. 19.5 ± 2.7 mmHg for LTFC) (P < 0.001). Further, TTFC demonstrated significantly better tear film break-up time (5.15 vs. 4.65 s), corneal stain (1.5 vs. 1.8) and Schirmer I test (9.9 vs. 9.2 mm) compared with LTFC after 3 months of therapy (P < 0.01 for all comparisons).Conclusion
The mean 24-h IOP lowering of TTFC was statistically more significant compared to LTFC in patients insufficiently controlled with latanoprost monotherapy. Measurement of ocular surface health and tear film status favored the BAK-free TTFC compared to LTFC. 相似文献995.
Omar El-Taji Abdullah Al-Mitwalli Farhan Malik Samita Agarwal Andrew Gogbashian Rob Hughes Nikhil Vasdev Anand Sharma 《Translational andrology and urology》2021,10(6):2427
BackgroundSecondary neoplasms of the bladder account for 4.5% of all bladder neoplasms however there is limited literature reporting management and survival. This is the largest single centre series presented in current literature with long term oncological follow up.MethodsThis is a single institutional, retrospective cohort study of patients with a histological diagnosis of a secondary bladder neoplasm from January 2007 to December 2017 (n=40). Prognostic variables examined included age at diagnosis, histology, disease free survival and treatment. Kaplan-Meier analysis was used to calculate survival. We used multiple regression analysis to identify the most significant treatments for each population group in terms of their survival.ResultsTwenty-one patients were male (53%) with a median age of 68 and 19 were female (47%) with a median age of 64. The most common secondary neoplasms and their median survival were prostate [12 patients (30%), 446 days], colorectal [9 patients (23%), 403 days], ovarian [5 patients (13%), 369 days], cervical [4 patients (10%), 148 days], breast [3 patients (8%), 241 days], lymphoma [3 patients (8%), 145 days], gastric [2 patients (5%), 66 days], and renal [2 patients (5%), 854 days]. Those receiving treatment following a secondary diagnosis demonstrated statistical significance in survival for colorectal (surgery P=0.013), prostate (radiotherapy P=0.0012 and hormonal therapy P=0.004) and ovarian cancer (chemotherapy P=0.00002).ConclusionsPrognosis and treatment depends upon the primary neoplasm. There is some survival benefit in well selected patients receiving treatment following a diagnosis of a bladder secondary. 相似文献
996.
Lubna Khatoon Frederick N. Baliraine Salman A. Malik Guiyun Yan 《The Brazilian journal of infectious diseases》2013,17(5):596-600
Plasmodium vivax and Plasmodium falciparum are becoming resistant to drugs including antifolates, sulphonamides and chloroquine. This study was focused at sequence analysis of resistant genes of these parasites against sulphadoxine–pyrimethamine and chloroquine, from Bannu, Pakistan. Known mutations were detected at codons 57, 58 and 117 of pvdhfr gene of P. vivax, while none of the isolates had any pvdhps mutation. Similarly P. falciparum isolates exhibited double 59R + 108N mutations in pfdhfr, and single 437G in pfdhps thus demonstrating the existance of triple mutant 59R + 108N + 437G haplotype in this region. The key chloroquine resistance mutation, 76T in pfcrt was observed in 100% of the P. falciparum isolates, with haplotype SVMNT which is also associated with resistance to amodiaquine. Some novel mutations were also observed in pvdhfr and pfdhfr genes. 相似文献
997.
Mitra Tavakoli Ioannis N. Petropoulos Rayaz A. Malik 《Journal of diabetes science and technology》2013,7(5):1179-1189
Accurate detection and quantification of human diabetic peripheral neuropathy are important to define at-risk patients, anticipate deterioration, and assess new therapies. Easily performed clinical techniques such as neurological examination, assessment of vibration perception or insensitivity to the 10 g monofilament only assess advanced neuropathy, i.e., the at-risk foot. Techniques that assess early neuropathy include neurophysiology (which assesses only large fibers) and quantitative sensory testing (which assesses small fibers), but they can be highly subjective while more objective techniques, such as skin biopsy for intra-epidermal nerve fiber density quantification, are invasive and not widely available. The emerging ophthalmic technique of corneal confocal microscopy allows quantification of corneal nerve morphology and enables clinicians to diagnose peripheral neuropathy in diabetes patients, quantify its severity, and potentially assess therapeutic benefit. The present review provides a detailed critique of the rationale, a practical approach to capture images, and a basis for analyzing and interpreting the images. We also critically evaluate the diagnostic ability of this new noninvasive ophthalmic test to diagnose diabetic and other peripheral neuropathies. 相似文献
998.
Bashir Ahmad Laway Tajamul Syed Malik Shoukat Hussain Khan Tanveer Ahmad Rather 《Journal of diabetes and its complications》2013,27(1):78-81
ObjectiveEffects of systemic hyperglycemia and normoglycemia on gastric emptying in people with type 2 diabetes are not clear. The aim of the study was to investigate the gastric emptying time in people with newly detected diabetes before and after control of diabetes compared with healthy controls.MethodsGastric emptying to solid meal was studied in 30 asymptomatic women with newly detected diabetes before and after achieving euglycemia and compared with 20 healthy age, sex and weight matched controls using egg white labelled with Technetium 99 m Sulfur Colloid.ResultsDelayed gastric emptying was seen in 90% of women with diabetes and none in healthy controls. Lag phase was 83.1 ± 11.8 min in cases compared to 37.2 ± 4.0 in controls (p = 0.05). Gastric emptying at 4 h was 46.73% ± 4.84% in cases and 97.65% ± 0.59% in controls (p = 0.05).T50 was 250 ± 8.8 min in cases against 94.70 ± 5.10 min in controls (p < 0.05). After control of diabetes, lag phase normalized to 37.2 ± 4.0 min against 35.2 ± 4.6 min in controls. Similarly all other parameters also normalized after control of diabetes.ConclusionsDelayed gastric emptying to solids was seen in 90% of women with type 2 diabetes at the time of hyperglycemia and normalized after control of diabetes. 相似文献
999.
1000.