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101.
Fetal hypothalamo-pituitary-adrenal (HPA) activity increases dramatically at term in sheep, however, little is known about the regulation of glucocorticoid feedback in the developing brain. Heat shock protein 70 (hsp70) is closely associated with glucocorticoid actions within the cell. We hypothesized that there is a decrease in glucocorticoid negative feedback in the brain, near term, resulting from changes in the expression of glucocorticoid receptors (GR) and hsp70. Brains were removed at various stages of development. GR mRNA levels in the paraventricular nucleus (PVN) and cortex, and hsp70 mRNA in the PVN were determined by in situ hybridization. In the hippocampus, GR mRNA levels were measured by Northern analysis. In the PVN, GR mRNA was present by d60. GR mRNA levels reached a peak at d100-110, but then decreased significantly with progression of gestation, and were lowest at term. Hippocampal GR mRNA levels were highest on day 130 of gestation, decreasing to low levels at term. In the cerebral cortex, GR mRNA levels were expressed at high levels in all layers of the cortex by day 110 of gestation with levels decreasing to term. Hsp70 mRNA was present in both parvocellular and magnocellular regions of the PVN, and there was no significant change in late gestation. In conclusion, (1) The high levels of GR mRNA present in the PVN, hippocampus and cerebral cortex during fetal life are likely important in development of these structures at a time when circulating glucocorticoids are low. (2) Changes in GR mRNA levels in the PVN are not associated with alterations in the expression of hsp70. (3) The decrease in GR mRNA in the hippocampus and PVN in late gestation, at a time when fetal plasma cortisol is increasing, likely facilitates maintained hypothalamic drive to the pituitary corticotroph. 相似文献
102.
Parker JC McPherson RK Andrews KM Levy CB Dubins JS Chin JE Perry PV Hulin B Perry DA Inagaki T Dekker KA Tachikawa K Sugie Y Treadway JL 《Diabetes》2000,49(12):2079-2086
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
103.
Andrews P Dovey E Hockaday J Hoyle CH Woods AJ Matsuki N 《Brain research. Developmental brain research》2000,121(1):29-34
The emetic (retching and vomiting) reflex is an important component of the body's defence system against accidentally ingested toxins and emesis is also a common symptom of disease and a side-effect of a number of pharmacological therapies. The development of the reflex has been the subject of few systematic studies. The aim of this study was to characterise the development of the emetic reflex in Suncus murinus (the house musk shrew) using emetic stimuli acting via three different afferent pathways: motion via the vestibular system, pyrogallol via abdominal vagal afferents and resiniferatoxin (a capsaicin analog) via the brainstem. The emetic reflex was not present to any stimulus prior to postnatal day 10 but the onset of the response to motion lagged behind that to the other stimuli in not being present until postnatal day 15. Body weight was not a determinant of the presence of the reflex. It is proposed that the delayed presence of the emetic reflex in Suncus makes it an ideal species in which to investigate factors regulating its development. 相似文献
104.
Mok MH Knight GE Andrews PL Hoyle CH Burnstock G 《Journal of the autonomic nervous system》2000,80(3):130-136
This study has shown that cyclophosphamide treatment of the insectivore Suncus murinus, causes a down regulation in both muscarinic and P2X receptors, together with a reduced responsiveness to exogenous histamine (0.3 mM) in the urinary bladder. Electrical field stimulation (70 V, 0.3 ms, 0.5-16 Hz, 10 s every 5 min) of bladders from both control and cyclophosphamide-treated animals showed identical responses. Since post-junctional alterations have been revealed by the reduced responsiveness to exogenous carbachol (0.1 microM-3 mM) and beta,gamma-methylene ATP (0.3-300 microM), it would appear that in the bladders of cyclophosphamide-treated animals there is also a pre-junctional effect, increased transmitter release compensating for the down regulation of the receptors. As the pattern of neurotransmission of the bladder of suncus more closely resembles that of human detrusor than other commonly studied laboratory animals, this insectivore appears to be a useful animal model for the study of bladder neurotransmission in pathophysiological conditions. 相似文献
105.
106.
OBJECTIVE: To describe the effect of an extended-spectrum prophylactic antibiotic regimen on postcesarean endometritis. METHODS: This is a cohort study of trends in postcesarean endometritis using data both from prospective surveillance by the infection control unit and from query of our obstetric computerized database to compare three periods of antibiotic prophylaxis: standard narrow-spectrum with intravenous first- or second-generation cephalosporin (1992-1996), clinical trial of extended-spectrum with addition of intravenous doxycycline and oral azithromycin (1997-1999), and routine use of extended-spectrum with addition of intravenous azithromycin (2001-2006) to standard cephalosporin prophylaxis. RESULTS: A total of 48,913 deliveries at 24 weeks or more of gestation occurred from 1992 to 2006, of which 10,966 (22.4%) were cesarean deliveries. Annual cesarean rates increased from 16% to 27.5%. Trends in the incidence of postcesarean endometritis revealed a biphasic decrease consistent with the phased introduction of extended-spectrum prophylaxis. Incidence (95% confidence interval [CI]) of endometritis by prospective surveillance dropped from 19.9% (95% CI 18.6-21.3%) to 15.4% (95% CI 13.2-17.9%) during the clinical trial period: relative risk (RR) 0.77 (95% CI 0.66-0.91), P=.002; and then to 6.3% (95% CI 5.0-7.9%) during routine use of extended-spectrum prophylaxis: RR 0.41 (95% CI 0.31-0.54), P<.001. Corresponding incidence by database query dropped from 23% (95% CI 21.5-24.4%) to 16% (95% CI 14.4-17.9%): RR 0.69 (95% CI 0.61-0.79), P<.001; and then to 2.1% (95% CI 1.8-2.6%): RR 0.13 (95% CI 0.11-0.16), P<.001. These findings were unchanged after adjusting for potential confounders. CONCLUSION: Extended-spectrum antibiotic prophylaxis involving the addition of azithromycin to standard narrow-spectrum prophylaxis was associated with a significant reduction in postcesarean endometritis. LEVEL OF EVIDENCE: II. 相似文献
107.
108.
Nicki L. Boddington Punam Mangtani Hongxin Zhao Neville Q. Verlander Joanna Ellis Nick Andrews Richard G. Pebody 《Influenza and other respiratory viruses》2022,16(5):897
IntroductionIn 2013, the United Kingdom began to roll‐out a universal annual influenza vaccination program for children. An important component of any new vaccination program is measuring its effectiveness. Live‐attenuated influenza vaccines (LAIVs) have since shown mixed results with vaccine effectiveness (VE) varying across seasons and countries elsewhere. This study aims to assess the effectiveness of influenza vaccination in children against severe disease during the first three seasons of the LAIV program in England.MethodsUsing the screening method, LAIV vaccination coverage in children hospitalized with laboratory‐confirmed influenza infection was compared with vaccination coverage in 2–6‐year‐olds in the general population to estimate VE in 2013/14–2015/16.ResultsThe overall LAIV VE, adjusted for age group, week/month and geographical area, for all influenza types pooled over the three influenza seasons was 50.1% (95% confidence interval [CI] 31.2, 63.8). By age, there was evidence of protection against hospitalization from influenza vaccination in both the pre‐school (2–4‐year‐olds) (48.1%, 95% CI 27.2, 63.1) and school‐aged children (5–6‐year‐olds) (62.6%, 95% CI 2.6, 85.6) over the three seasons.ConclusionLAIV vaccination in children provided moderate annual protection against laboratory‐confirmed influenza‐related hospitalization in England over the three influenza seasons. This study contributes further to the limited literature to date on influenza VE against severe disease in children. 相似文献
109.
Mustafa M. Haddad Chad J. Fleming Scott M. Thompson Christopher J. Reisenauer Ahmad Parvinian Gregory Frey Beau Toskich James C. Andrews 《Journal of vascular and interventional radiology : JVIR》2018,29(10):1383-1391
Purpose
To evaluate the incidence of bleeding complications between transplenic (TS) and transhepatic (TH) access in portal venous interventions.Materials and Methods
Retrospective review of patients who underwent TS or TH access for portal venous system interventions from January 2000 to August 2017. Only procedures with clinical and laboratory follow-up were included (n = 148). Twenty-four TS procedures were performed in 22 patients, and 124 TH procedures were performed in 114 patients. The main indications were for angioplasty/stent, embolization of varices/shunt, or portal vein embolization, with no difference between the groups. Mean patient age and sex were not significantly different between the groups (P values .445 and .682, respectively). Mean follow up was 2.3 years (range 0.1–14.2). There was no significant difference between the international normalized ratio (P = .300) and platelets (P = .234) before the procedure between the 2 cohorts.Results
Technical success of vascular access and procedural success was achieved in 22/24 (91.6%) TS procedures and 120/124 (96.8%) TH procedures (P = .238). There was no significant difference in bleeding complications between the 2 groups (3/24 [12.5%] TS vs 10/124 [8.1%] TH; P = .44). There was no significant difference in major bleeding complications (SIR classification ≥ C; 1/24 [4.2%] TS vs 4/124 [3.2%] TH; P = .789).There was no significant difference in the hemoglobin before or after the procedure (g/dL), with average change ?1.1 g/dL (range ?3.4 to +1.0) in the TS group and 1.0 g/dL (range ?4.5 to +1.9) in the TH group (P = .540). Finally, there was no significant difference in proportion of patients requiring blood transfusion after the procedure (P = .520), with 2 (8.3%) in the TS group requiring an average of 4 units (range 2–6) and 17 (13.7%) in the TH group requiring an average of 3.5 units (range 1–26).Conclusions
These data suggest no significant difference in bleeding complications between TS and TH access for portal venous interventions. 相似文献110.
Keogh CF Andrews GT Spacey SD Forkheim KE Graeb DA 《AJR. American journal of roentgenology》2003,180(3):847-850
OBJECTIVE: Our objective was to illustrate the dramatic neuroimaging findings of toxic leukoencephalopathy caused by heroin vapor inhalation. CONCLUSION: Symmetric abnormality involving the cerebellar white matter and posterior limb of the internal capsule is characteristic of heroin vapor inhalation toxicity, although involvement may be more extensive, depending on the severity of the condition. MR imaging and CT appear to be essential for making this diagnosis because clinical history is often unreliable and findings at physical examination are nonspecific. 相似文献