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Urinary bladder cancers occurring after prolonged cyclophosphamide therapy are being increasingly reported. Cyclophosphamide-induced cancer in the upper urinary tract is not, however, generally recognized. We report a case of asynchronous development of transitional cell carcinoma in the bladder and renal pelvis, after prolonged cyclophosphamide therapy for non-Hodgkin's lymphoma. To date, at least 8 cyclophosphamide-related cancers have been reported in the upper tract. These cases are reviewed briefly.  相似文献   
54.
Peptidic glucagon antagonists have been shown to lower blood glucose levels in diabetic models (1-3), but attempts to identify small molecular weight glucagon receptor-binding antagonists have met with little success. Skyrin, a fungal bisanthroquinone, exhibits functional glucagon antagonism by uncoupling the glucagon receptor from adenylate cyclase activation in rat liver membranes (1). We have examined the effects of skyrin on cells transfected with the human glucagon receptor and on isolated rat and human hepatocytes. The skyrin used was isolated from Talaromyces wortmanni American Type Culture Collection 10517. In rat hepatocytes, skyrin (30 micromol/l) inhibited glucagon-stimulated cAMP production (53%) and glucose output (IC50 56 micromol/l). There was no detectable effect on epinephrine or glucagon-like peptide 1 (GLP-1) stimulation of these parameters, which demonstrates skyrin's selective activity. Skyrin was also evaluated in primary cultures of human hepatocytes. Unlike cell lines, which are largely unresponsive to glucagon, primary human hepatocytes exhibited glucagon-dependent cAMP production for 14 days in culture (EC50 10 nmol/l). Skyrin (10 micromol/l) markedly reduced glucagon-stimulated cAMP production (55%) and glycogenolysis (27%) in human hepatocytes. The inhibition of glucagon stimulation was a specific property displayed by skyrin and oxyskyrin but not shared by other bisanthroquinones. Skyrin is the first small molecular weight nonpeptidic agent demonstrated to interfere with the coupling of glucagon to adenylate cyclase independent of binding to the glucagon receptor. The data presented in this study indicate that functional uncoupling of the human glucagon receptor from cAMP production results in metabolic effects that could reduce hepatocyte glucose production and hence alleviate diabetic hyperglycemia.  相似文献   
55.
Although several investigations have suggested cardiac epinephrine (Epi) release, local Epi release in the myocardial interstitium in vivo has not been measured. Using cardiac microdialysis in the rabbit, we measured dialysate Epi and norepinephrine (NE) concentrations as indices of myocardial interstitial Epi and NE levels, respectively. Exocytotic release induced by local administration of KCl (100 mM) through the dialysis probe increased Epi to 24.2 +/- 13.2 pg/ml from a control value of 3.2 +/- 3.6 pg/ml (P < 0.01, n = 6). Non-exocytotic release induced by the local administration of tyramine (10 microg/ml) also increased Epi to 34.6 +/- 15.3 pg/ml (p < 0.05 from control, n = 6). We conclude that Epi can be released via both exocytotic and non-exocytotic release mechanisms from the heart.  相似文献   
56.
Aims/IntroductionThe Canagliflozin and Renal Events in Diabetes with Established Nephropathy Clinical Evaluation (CREDENCE) trial has shown the effects of canagliflozin on preventing clinically important kidney outcomes in patients with type 2 diabetes mellitus and chronic kidney disease; however, not many Japanese patients were included in the trial. The present study evaluated the efficacy and safety of canagliflozin in Japanese chronic kidney disease patients with type 2 diabetes mellitus.Materials and MethodsIn this multicenter, randomized, double‐blind, placebo‐controlled, parallel‐group, phase III study, chronic kidney disease patients with type 2 diabetes mellitus were randomly assigned to receive either 100 mg canagliflozin or a matching placebo once daily for 104 weeks. The primary efficacy end‐point was the incidence of a 30% decline in estimated glomerular filtration rate.ResultsOverall, 308 patients were randomized to the canagliflozin (n = 154) and placebo (n = 154) groups. The incidence of a 30% decline in estimated glomerular filtration rate at week 104 was 18.2% and 29.5%, respectively, and the point estimate of the intergroup difference (placebo − canagliflozin) was 11.3% (95% confidence interval 1.2–21.5, P = 0.029), which was significant. The overall incidence of adverse events was similar in the two groups.ConclusionsThis study suggests that canagliflozin safely reduces the risk of end‐stage renal disease in Japanese chronic kidney disease patients with type 2 diabetes mellitus.  相似文献   
57.
Self-enhancement, the tendency to view oneself positively, is a pervasive social motive widely investigated in the psychological sciences. Relatively little is known about the neurocognitive mechanisms underlying this motive, specifically in social-evaluative situations. To investigate whether positive emotion regulation circuitry, circuitry involved in modulating positive affect, relates to the self-enhancement motive in social contexts, we conducted an functional magnetic resonance imaging (fMRI) study in a healthy young adult sample. We hypothesized that self-enhancement indices (state and trait self-esteem) would relate to greater functional connectivity between right ventrolateral prefrontal cortex (RVLPFC), a region implicated in emotion regulation, and the ventral striatum (VS), a region associated with reward-related affect, during a social feedback task. Following social evaluation, participants experienced stable or decreased state self-esteem. Results showed that stable state self-esteem from pre- to post-scan and higher trait self-esteem related to greater RVLPFC–VS connectivity during positive evaluation. Stable-state self-esteem also related to greater RVLPFC–VS connectivity during negative evaluation. Moreover, RVLPFC activation during all types of feedback processing and left VS activation during negative feedback processing was greater for participants with stable-state self-esteem. These findings implicate neurocognitive mechanisms underlying emotion regulation in the self-enhancement motive and highlight a pathway through which self-enhancement may restore feelings of self-worth during threatening situations.  相似文献   
58.
Even with current promising antitumor antibodies, their antitumor effects on stroma‐rich solid cancers have been insufficient. We used mild hyperthermia with the intent of improving drug delivery by breaking the stromal barrier. Here, we provide preclinical evidence of cetuximab + mild hyperthermia therapy. We used four in vivo pancreatic cancer xenograft mouse models with different stroma amounts (scarce, MIAPaCa‐2; moderate, BxPC‐3; and abundant, Capan‐1 and Ope‐xeno). Cetuximab (1 mg/kg) was given systemically, and the mouse leg tumors were concurrently heated using a water bath method for 30 min at three different temperatures, 25°C (control), 37°C (intra‐abdominal organ level), or 41°C (mild hyperthermia) (n = 4, each group). The evaluated variables were the antitumor effects, represented by tumor volume, and in vivo cetuximab accumulation, indirectly quantified by the immunohistochemical fluorescence intensity value/cell using antibodies against human IgG Fc. At 25°C, the antitumor effects were sufficient, with a cetuximab accumulation value (florescence intensity/cell) of 1632, in the MIAPaCa‐2 model, moderate (1063) in the BxPC‐3 model, and negative in the Capan‐1 and Ope‐xeno models (760, 461). By applying 37°C or 41°C heat, antitumor effects were enhanced shown in decreased tumor volumes. These enhanced effects were accompanied by boosted cetuximab accumulation, which increased by 2.8‐fold (2980, 3015) in the BxPC‐3 model, 2.5‐ or 4.8‐fold (1881, 3615) in the Capan‐1 model, and 3.2‐ or 4.2‐fold (1469, 1922) in the Ope‐xeno model, respectively. Cetuximab was effective in treating even stroma‐rich and k‐ras mutant pancreatic cancer mouse models when the drug delivery was improved by combination with mild hyperthermia.  相似文献   
59.
Although embryo screening by preimplantation genetic diagnosis (PGD) has become the standard technique for the treatment of recurrent pregnancy loss in couples with a balanced gross chromosomal rearrangement, the implantation and pregnancy rates of PGD using conventional fluorescence in situ hybridization (FISH) remain suboptimal. Comprehensive molecular testing, such as array comparative genomic hybridization and next‐generation sequencing, can improve these rates, but amplification bias in the whole genome amplification method remains an obstacle to accurate diagnosis. Recent advances in amplification procedures combined with improvements in the microarray platform and analytical method have overcome the amplification bias, and the data accuracy of the comprehensive PGD method has reached the level of clinical laboratory testing. Currently, comprehensive PGD is also applied to recurrent pregnancy loss due to recurrent fetal aneuploidy or infertility with recurrent implantation failure, known as preimplantation genetic screening. However, there are still numerous problems to be solved, including misdiagnosis due to somatic mosaicism, cell cycle‐related background noise, and difficulty in diagnosis of polyploidy. The technology for comprehensive PGD also requires further improvement.  相似文献   
60.
Branhamella catarrhalis has been misconsidered as a normal resident in human respiratory tract for a long time. However, many authors recently have reported its pathogenecity and isolated it from the otolaryngological region. In our study, this organism can be isolated from the ear and nasal discharge in the child with acute otitis media by the rate of 7.5% and 21.4% respectively. Out of this 107 isolated strains, 97 strains (90.7%) were found to be beta-lactamase producing organisms. The MIC measurement of penicillins and cephems (except CEX) for inhibition of all these strains in our study is 6.25 micrograms/ml or less and because of the unreliability of the ABPC's susceptibility test by disk method, it is necessary to check the beta-lactamase production in each strain. Becoming of the high emergence rate of beta-lactamase producing strains, B. catarrhalis should be considered to be as important pathogen as Streptococcus pneumoniae and Haemophilus influenzae in upper respiratory tract infections in children.  相似文献   
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