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51.
Gonadotropin-inhibitory hormone neurons interact directly with gonadotropin-releasing hormone-I and -II neurons in European starling brain 总被引:3,自引:0,他引:3
Ubuka T Kim S Huang YC Reid J Jiang J Osugi T Chowdhury VS Tsutsui K Bentley GE 《Endocrinology》2008,149(1):268-278
Gonadotropin-inhibitory hormone (GnIH) is a hypothalamic dodecapeptide (SIKPSAYLPLRF-NH(2)) that directly inhibits gonadotropin synthesis and release from quail pituitary. The action of GnIH is mediated by a novel G-protein coupled receptor. This gonadotropin-inhibitory system may be widespread in vertebrates, at least birds and mammals. In these higher vertebrates, histological evidence suggests contact of GnIH immunoreactive axon terminals with GnRH neurons, thus indicating direct regulation of GnRH neuronal activity by GnIH. In this study we investigated the interaction of GnIH and GnRH-I and -II neurons in European starling (Sturnus vulgaris) brain. Cloned starling GnIH precursor cDNA encoded three peptides that possess characteristic LPXRF-amide (X = L or Q) motifs at the C termini. Starling GnIH was further identified as SIKPFANLPLRF-NH(2) by mass spectrometry combined with immunoaffinity purification. GnIH neurons, identified by in situ hybridization and immunocytochemistry (ICC), were clustered in the hypothalamic paraventricular nucleus. GnIH immunoreactive fiber terminals were present in the external layer of the median eminence in addition to the preoptic area and midbrain, where GnRH-I and GnRH-II neuronal cell bodies exist, respectively. GnIH axon terminals on GnRH-I and -II neurons were shown by GnIH and GnRH double-label ICC. Furthermore, the expression of starling GnIH receptor mRNA was identified in both GnRH-I and GnRH-II neurons by in situ hybridization combined with GnRH ICC. The cellular localization of GnIH receptor has not previously been identified in any vertebrate brain. Thus, GnIH may regulate reproduction of vertebrates by directly modulating GnRH-I and GnRH-II neuronal activity, in addition to influencing the pituitary gland. 相似文献
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Fazle Rabbi Chowdhury Md. Mustafezur Rahman Parash Ullah Abdul Mumith Ruhan Md. Shafiqul Bari M. M. Jahangir Alam 《Clinical toxicology (Philadelphia, Pa.)》2018,56(9):820-827
Background: Treatment of acute organophosphorus (OP) insecticide poisoning is difficult, with many patients dying despite best care. Pre-clinical studies have shown benefit from salbutamol, possibly due speeding alveolar fluid clearance or reducing bronchoconstriction. In this small pilot dose-response study, we aimed to explore whether addition of nebulized salbutamol to standard care might improve resuscitation.Methods: We performed a single-blind phase II study comparing the effect of two different doses of nebulized salbutamol versus saline placebo, in addition to standard treatment. Primary outcome was oxygen saturations over the first 60?min of resuscitation; secondary outcomes included heart rate, incidence of dysrhythmias, time to ‘atropinization’, atropine dose required, and mortality.Result: Seventy-five patients were randomized to receive 5?mg (Salb5, n?=?25) or 2.5mg (Salb2.5, n?=?25) of salbutamol, or saline placebo (NoSalb, n?=?25), by nebulizer. Oxygen saturations did not differ between groups over the first 60?min of resuscitation (median AUC NoSalb: 1376 [95% CI 1282 to 1470], Salb2.5: 1395 [1305 to 1486], Salb5: 1233 [1100 to 1367]; p?=?.9898). Heart rate was also similar across the three arms. Median time to full atropinization, and atropine dose required, were the same for all three arms (NoSalb 15.0 [10–16] min and 12.6 [8.0–13.4] mg, Salb2.5 15.0 [10–16] min and 12.6 [9.3–16.8] mg, and Salb5 15.0 [10–20] min and 12.6 [10.7–20.6] mg; p?=?.4805 and p?=?.1871, respectively). Three (12%) patients died in the Salb2.5 and Salb5 groups and two (8%) in the NoSalb group.Conclusion: This pilot study, within the limitations of its small size and variation between patients, found no apparent evidence that administration of nebulized salbutamol improved resuscitation of patients with acute OP insecticide self-poisoning. The data obtained provides a basis to design further studies to ultimately test the role of salbutamol in OP insecticide poisoning. 相似文献
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We report the case of a 19-year old boy presenting in the emergency with severe epigastric pain whose biochemical tests revealed elevated serum amylase and lipase levels and a clinical diagnosis of acute pancreatitis was made. On ultrasonic examination, the pancreas appeared bulky with a linear tubular echogenic worm (ascaris) seen within the prominent main pancreatic duct. Successful removal of the pancreatic duct worm was achieved through endoscopic retrograde cholangio pancreatography (ERCP). 相似文献
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Treatment of liver failure in rats with end-stage cirrhosis by transplantation of immortalized hepatocytes 总被引:12,自引:0,他引:12
Cai J Ito M Nagata H Westerman KA Lafleur D Chowdhury JR Leboulch P Fox IJ 《Hepatology (Baltimore, Md.)》2002,36(2):386-394
The shortage of organ donors has impeded the development of human hepatocyte transplantation. Immortalized hepatocytes could provide an unlimited supply of transplantable cells. To determine whether immortalized hepatocytes could provide global metabolic support in end-stage liver disease, 35 immortalized rat hepatocyte clones were developed by transduction with the gene encoding the simian virus 40 T antigen (SV40Tag). The SV40Tag sequence and a suicide gene, herpes simplex virus thymidine kinase (HSV-tk), were flanked by loxP sequences so that they could be excised by Cre/lox recombination. When transplanted into the spleens of portacaval-shunted rats, 3 of the 35 immortalized hepatocyte clones prevented the development of hyperammonemia-induced hepatic encephalopathy. The protection was reversed by treatment with ganciclovir, which kills HSV-tk-expressing cells. Transplantation of alginate-encapsulated, immortalized hepatocytes into the spleens of cirrhotic rats resulted in significant improvement in prothrombin time, serum albumin and bilirubin levels, hepatic encephalopathy score, and duration of survival. The metabolic support provided by the immortalized cells equaled that observed after transplantation of primary rat hepatocytes. In conclusion, immortalized hepatocytes can function as well as primary hepatocytes following transplantation and can be engineered to contain safeguards that could make them clinically useful. Further investigation is warranted regarding the mechanisms of loss of mass or function of the transplanted hepatocytes over time and how the relatively few engrafted hepatocytes can ameliorate liver decompensation in cirrhosis. 相似文献
57.
Brian D. Adkins Theresa A. Libby Marlene M. Mayberry Thomas W. Brady Justin B. Halls Stephanie Mallow Corbett Joseph Schoeny Eric P. Shields Jahan Chowdhury Amanda N. Kinsinger-Stickel Gay Wehrli Nicholas R. Jaeger Matthew P. Robertson Kathy M. Butler Stuart M. Lowson James Forrest Calland James D. Gorham 《Transfusion》2021,61(11):3066-3074
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Samiran Upadhyaya Achyut Konwar Devasish Chowdhury Neelotpal Sen Sarma 《RSC advances》2020,10(43):25408
Water-borne adhesives have immense importance in cellulose-based materials, where their durability, handling, and strength remain to be a major concern. The present work demonstrates the development of three water-borne adhesives, namely, poly(1-vinyl-2-pyrrolidone-co-acrylic acid), poly(acrylonitrile-co-acrylic acid), and poly(1-vinyl-2-pyrrolidone-co-acrylonitrile-co-acrylic acid) applicable for cellulose-based materials. These acrylic-acid based adhesives were characterized by Fourier-transform infra-red spectroscopy, thermogravimetric analysis, X-ray diffraction, gel permeation chromatography, and universal testing machine. The synthesized polymer adhesives can be stored in the powder form for a longer period, thus utilizing less space. In order to use as adhesives, suitable formulations can be prepared in water. The adhesives show thermal stability up to 300 °C. Our studies show that poly(1-vinyl-2-pyrrolidone-co-acrylonitrile-co-acrylic acid) showed higher lap shear strength (ASTM D-906) than commercially available adhesives. In addition, these adhesives, being fluorescent in nature, can be detected under UV light and thus are applicable for the detection of fractured joints of any specimen. This property also helps in anti-counterfeiting applications, thus adding further to their utility.Synthesis and application of a water-borne fluorescent acrylic adhesive, which can be stored as a powder for long-term use. 相似文献
60.
Investigation of glutamine and GABA levels in patients with idiopathic generalized epilepsy using MEGAPRESS 下载免费PDF全文