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Summary In 5 closely controlled pregnant diabetics (duration of pregnancy 237–266 days) and 5 pregnant non-diabetics (duration of pregnancy 210–278 days) 4-hourly blood samples were taken throughout a 24 h period and analyzed for blood glucose, lactate, pyruvate, 3-hydroxybutyrate and acetoacetate, plasma non-esterified fatty acids (NEFA), glucagon and cortisol. 24 h urine specimen was analyzed for total catecholamines and 4-hydroxy-3-methoxymandelic acid. There were few significant differences in concentrations of metabolites and hormones in the two groups at any time, although the variations about the mean was usually greater in the diabetics. Thus for blood glucose in diabetics, mean value was 4.4 mmol/l, coefficient of variation 43%; in non-diabetics 4.1 mmol/l and 10% respectively. Mean plasma 3-hydroxybutyrate in diabetics was 0.47 mmol/l, coefficient of variation 55%; in non-diabetics 0.44 mmol/l and 37% respectively. Plasma non-esterified fatty acid levels were significantly higher in the diabetics (0.47 mmol/l) than in the non-diabetics (0.26 mmol/l). Coefficients of variation were 46% and 33% respectively. Two conclusions can be drawn; first, when near normal mean values for blood glucose are achieved, other metabolite and hormone levels are also near normal; second, even when the available means for diabetic control, strict diet and insulin-mixtures twice daily, are used at their maximum, metabolism in diabetics is more unstable than in non-diabetics. 相似文献
65.
Dr. N. M. Gupta M.S. A. Chaudhary M.S. V. Nanda M.D. A. K. Malik M.D. J. D. Wig M.S. F.R.C.S. 《Diseases of the colon and rectum》1985,28(6):451-453
Erosion of a retained surgical sponge into the intestine is an unusual occurrence and may make its appearance months or years
later. The demonstration of a distended bowel by the barium-impregnated mass with multiple polypoidal filling defects in a
patient who has undergone previous laparotomy should lead the physician to suspect a retained surgical sponge. Surgical intervention
is rewarding. 相似文献
66.
Tuning the endothelial response: differential release of exocytic cargos from Weibel‐Palade bodies
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T. D. Nightingale J. J. McCormack W. Grimes C. Robinson M. Lopes da Silva I. J. White A. Vaughan L. P. Cramer D. F. Cutler 《Journal of thrombosis and haemostasis》2018,16(9):1873-1886
Essentials
- Endothelial activation initiates multiple processes, including hemostasis and inflammation.
- The molecules that contribute to these processes are co‐stored in secretory granules.
- How can the cells control release of granule content to allow differentiated responses?
- Selected agonists recruit an exocytosis‐linked actin ring to boost release of a subset of cargo.
Summary
Background
Endothelial cells harbor specialized storage organelles, Weibel‐Palade bodies (WPBs). Exocytosis of WPB content into the vascular lumen initiates primary hemostasis, mediated by von Willebrand factor (VWF), and inflammation, mediated by several proteins including P‐selectin. During full fusion, secretion of this large hemostatic protein and smaller pro‐inflammatory proteins are thought to be inextricably linked.Objective
To determine if secretagogue‐dependent differential release of WPB cargo occurs, and whether this is mediated by the formation of an actomyosin ring during exocytosis.Methods
We used VWF string analysis, leukocyte rolling assays, ELISA, spinning disk confocal microscopy, high‐throughput confocal microscopy and inhibitor and siRNA treatments to demonstrate the existence of cellular machinery that allows differential release of WPB cargo proteins.Results
Inhibition of the actomyosin ring differentially effects two processes regulated by WPB exocytosis; it perturbs VWF string formation but has no effect on leukocyte rolling. The efficiency of ring recruitment correlates with VWF release; the ratio of release of VWF to small cargoes decreases when ring recruitment is inhibited. The recruitment of the actin ring is time dependent (fusion events occurring directly after stimulation are less likely to initiate hemostasis than later events) and is activated by protein kinase C (PKC) isoforms.Conclusions
Secretagogues differentially recruit the actomyosin ring, thus demonstrating one mechanism by which the prothrombotic effect of endothelial activation can be modulated. This potentially limits thrombosis whilst permitting a normal inflammatory response. These results have implications for the assessment of WPB fusion, cargo‐content release and the treatment of patients with von Willebrand disease.67.
Morphometric observations on the effects of ischemia in the isolated perfused rat heart. 总被引:3,自引:0,他引:3
L P McCallister S Trapukdi J R Neely 《Journal of molecular and cellular cardiology》1979,11(7):619-630
The design of the experiment was to observe the changes which took place in the isolated perfused rat heart, that was made ischemic according to the technique of Neely et al. [16], using quantitative stereological techniques. The results showed that 24 min after myocardial failure there was a significant decrease in the fractional volume of myofibrils, mitochondria, T-system, and sarcoplasmic reticulum. The decrease in fractional volume of subcellular organelles can most probably be explained by myocardial cell swelling secondary to intercellular edema. There was also a decrease in the sarcoplasmic reticulum membrane area, and quantitative measurements indicated that this compartment was dilated. Observations on the intercalated disc indicated that there was a migration of acid phosphatase positive multivesicular bodies toward the disc interspace in ischemic hearts. This was found to be associated with the dissolution of gap junctions. Stereological measurements indicated that in ischemic hearts there was a 5-fold increase in the percentage of membrane area of the disc made up of open gap junctions, and that the number of vesicles from multivesicular bodies observed per μm3 of disc interspace was also proportionately higher. It is suggested that the multivesicular bodies represent elements of the lysosomal system and are responsible for the dissociation of the intercalated disc in ischemic hearts. 相似文献
68.
Summary Serum growth hormone values in 37 patients with diabetic ketoacidosis were 5.4±0.8 ng/ml (S.E.M.) in males and 6.7±1.1 ng/ml in females before treatment; while in five hyperosmolar non-ketotic patients the HGH concentration was 3.9±0.5 ng/ml. One hour after insulin 90% of patients showed a rise in HGH, to a mean of 33.7±9.8 ng/ml for males and 25.5±6.0 ng/ml for females in ketoacidosis; and to 27.1±9.9 ng/ml for hyperosmolar coma patients. The rise, which was transient, was inversely correlated with pretreatment plasma glucose, the l h plasma glucose concentration and plasma urea, and directly proportional to the % fall in blood glucose after 1 h. When the ketoacidosis patients were divided into two groups according to HGH response, those with a small response had the greater disturbances of plasma glucose, blood ketone bodies, blood lactate, plasma urea, blood pH, and blood pressure, the smaller 1 h fall in blood glucose, and the higher mortality. Thus the most severely ketoacidotic patients had the poorest growth hormone response. Growth hormone is probably of little importance as an insulin antagonist in diabetic coma.Presented in part at the Spring Meeting of the British Diabetic Association, York, April 1972. 相似文献
69.
《Ultrastructural pathology》2013,37(6):344-350
Nanobacteria are controversial infectious agents with nanometric size, the capacity to nucleate hydroxyapatite and grow in culture, and present in human diseases associated with calcification and psammoma bodies. The authors report a case of pathological placental calcifications associated with nanobacteria. Electron microscopy and electron energy loss spectroscopy imaging were used to recognize 160-nm-sized calcium-free bodies mainly presenting as extracellular fibrillary tangles and 500-nm-sized calcified bodies; they encrusted the syncito-trophoblast basal membrane and aggregated into miniaturized psammoma bodies. Nanobacteria may be composed of a prionoid protein with self-assembling and self-propagating abilities whose growth is associated with the formation of psammoma bodies. 相似文献
70.
Raffaella Franciotti Nicola Walter Falasca Laura Bonanni Francesca Anzellotti Valerio Maruotti Silvia Comani Astrid Thomas Armando Tartaro John-Paul Taylor Marco Onofrj 《Neurobiology of aging》2013
Default mode network resting state activity in posterior cingulate cortex is abnormally reduced in Alzheimer disease (AD) patients. Fluctuating cognition and electroencephalogram abnormalities are established core and supportive elements respectively for the diagnosis of dementia with Lewy bodies (DLB). Our aim was to assess whether patients with DLB with both of these features have different default mode network patterns during resting state functional magnetic resonance imaging compared with AD. Eighteen patients with DLB, 18 AD patients without fluctuating cognition, and 15 control subjects were selected after appropriate matching and followed for 2–5 years to confirm diagnosis. Independent component analysis with functional connectivity (FC) and Granger causality approaches were applied to isolate and characterize resting state networks. FC was reduced in AD and DLB patients compared with control subjects. Posterior cingulate cortex activity was lower in AD than in control subjects and DLB patients (p < 0.05). Right hemisphere FC was reduced in DLB patients in comparison with control subjects but not in patients with AD, and was correlated with severity of fluctuations (ρ = −0.69; p < 0.01). Causal flow analysis showed differences between patients with DLB and AD and control subjects. 相似文献