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51.
Lynch G Kohler S Leser J Beil M Garcia-Marin LJ Lutz MP 《Pflügers Archiv : European journal of physiology》2004,448(4):445-451
The aim of this study was to establish whether the rate of fatty acid (FA) incorporation and its utilization by the isolated soleus muscle is modified under conditions of thyroid hormone deficit or excess. The rate of palmitic acid (PA) uptake, oxidation and incorporation into intramuscular lipids with increasing PA concentration (0.5–1.5 mM) in the incubation medium were determined. In hypothyroid rats intramuscular triacylglycerol (TG) synthesis was increased, while the rate of PA oxidation to CO2 and incorporation into mono- and diacylglycerols (MG/DG) and phospholipids (PL) remained unchanged. In rats with triiodothyronine (T3) excess the rate of all processes studied was enhanced, although the percentage incorporation of PA into different classes of intramuscular lipids was fairly constant and, independently of thyroid state and FA concentration in the medium, was 56–66% for TG, 9-14% for MG/DG and 24–32% for PL. Our results thus indicate that even short-term T3 excess accelerates the rate of FA uptake and metabolism in the oxidative soleus muscle, whereas in hypothyroid rats only intramuscular TG synthesis is affected. 相似文献
52.
The initial event in the regulatory volume increase (RVI) of rat hepatocytes is an influx of Na+ that is then exchanged for K+ via stimulation of Na+/K+-adenosine triphosphatase (ATPase). In this study, we analysed the activation pattern of the Na+ transporters underlying RVI as a function of the degree of hypertonic stress. In confluent primary cultures, four hypertonic conditions were tested (changes from 300 to 327, 360, 400 or 450 mosmol/l) and the activities of Na+ conductance, Na+/H+ antiport, Na+-K+-2Cl- symport and Na+/K+-ATPase were quantified using intracellular microelectrodes, microfluorometry and time-dependent, furosemide- or ouabain-sensitive 86Rb+ uptake, respectively. Neither Na+ conductance nor Na+-K+-2Cl- symport responded to 327 mosmol/A. At 360, 400 and 450 mosmol/l, uptake via these transporters would lead to increases of cell Na+ by 33.0, 49.0 and 49.0 and by 4.5, 10.4 and 9.2 mmol/l per 10 min, respectively. In contrast, Na+/H+ antiport exhibited 65% of its maximal activation already at 327 mosmol/l. At the four osmolarities tested, this transporter would augment cell Na+ by 6.9, 8.9, 9.8 and 10.6 mmol/l per 10 min. The sums of Na+ import were consistent with the amounts of Na+ exported via Na+/K+-ATPase plus the actual increases of cell Na+ (21.2, 58.5, 63.6 and 68.3 mmol/l per 10 min and 2.2, 4.0, 6.3 and 8.2 mmol/l, respectively). In addition, these elevations of cell Na+ plus the increases of cell K+ (via Na+/K+-ATPase) that amounted to 5.0, 6.5, 17.5 and 18.4 mmol/l were consistent with the increases of intracellular osmotic (cationic) activity of 2.5, 11.5, 21.0 and 28.5 mmol/l, respectively, computed from RVI data. It is concluded that the principle of rat hepatocyte RVI, i.e. an initial uptake of Na+ that is then exchanged for K+ via Na+/K+-ATPase, is realized over the entire range of 9-50% hypertonicity tested. The set-point for the activation of RVI clearly lies below 327 mosmol/l. Na+/H+ antiport is the most sensitive Na+ importer involved in RVI, whereas Na+ conductance plays the prominent role from 360 mosmol/l upwards. 相似文献
53.
The consumption of ethanol in a 10% solution for 3 weeks produced a negligible increase in corticosterone secretion in the rat but raised the levels of free fatty acid (FFA) in the serum. Mepyramine insignificantly antagonized and cimetidine intensified the corticosterone response. Histamine and the H1- and H2-receptor agonists, 2-pyridylethylamine (PEA) and dimaprit significantly raised the serum corticosterone levels in chronically alcoholized rats. Mepyramine antagonized and cimetidine increased the ethanol-induced hyperlipemia. Histamine, PEA and dimaprit considerably increased the serum FFA levels in alcoholized rats. After withdrawal of ethanol, histamine and dimaprit induced a marked hyperlipemic effect, whereas PEA did not increase the serum FFA concentration.These results indicate that in chronically alcoholized rats the central histaminergic system interacts with ethanol in regulation of the serum FFA level. After the ethanol withdrawal central H1-receptors do not respond to H1-agonist stimulation. 相似文献
54.
Theodore C. Iancu Hanna Shiloh Kishor B. Raja Robert J. Simpson Timothy J. Peters Daniel P. Perl Amy Hsu Paul F. Good 《The Journal of pathology》1995,177(1):83-94
Homozygote hypotransferrinaemic mice (hpx/hpx) have cytopathological features similar to those of human congenital atransferrinaemia, genetic haemochromatosis, and neonatal haemochromatosis. These conditions all have in common high levels of cytotoxic non-transferrin-bound serum iron. This study describes the ultrastructural features of iron overload in liver, pancreas, heart, and small intestine of 2- and 12-month-old hypotransferrinaemic mice. Electron microscopic studies of unstained sections showed early parenchymal cell siderosis, with accumulation of numerous ferritin particles and clusters in the cytosol, as well as ferritin and haemosiderin in lysosomes (siderosomes). In the 12-month-old animals, iron was also found in Kupffer cells and macrophages in other tissues. In addition, there were conspicuous iron-containing compounds in the bile canaliculi, and marked iron deposition in the pancreas and heart. Laser microprobe mass analysis (LAMMA) enabled localization and relative quantitation of iron deposition in subcellular compartments providing in situ documentation of iron accumulation in siderosomes and contributed in assessing total cytosolic iron in various cell types. Moreover, it demonstrated the importance and magnitude of the biliary route for iron excretion in these animals. 相似文献
55.
Polypeptides of mammalian oncornaviruses. III. Localization of p 15 and reactivity with natural antibody. 总被引:18,自引:0,他引:18
Antiserum to p15 of Friend murine leukemia virus (FLV) reacted with intact MuLV's in radioimmunoprecipitation (RIP) assays. The antigen-antibody complexes formed by this reaction were isolated and shown to contain p15 after analysis by SDS polyacrylamide gel electrophoresis. Natural antibody in mice to MuLV reacted in a similar fashion with p15, but in addition, also with the virus glycoproteins (gp71, gp45). Biological studies indicated that gp71 rather than p15 is principally involved in the virus-neutralization reaction. These and other studies indicate that p15 is localized on the virus surface and is recognized by natural antibodies in mice to MuLV. 相似文献
56.
PCR-based detection of Bacillus anthracis in formalin-fixed tissue from a patient receiving ciprofloxacin 总被引:3,自引:0,他引:3 下载免费PDF全文
Levine SM Perez-Perez G Olivares A Yee H Hanna BA Blaser MJ 《Journal of clinical microbiology》2002,40(11):4360-4362
We demonstrate that Bacillus anthracis may be detected from a formalin-fixed, paraffin-embedded biopsy specimen, even after the patient has received antibiotic treatment. Although traditional PCR methods may not be sufficiently sensitive for anthrax detection in such patients, cycle numbers can be increased or PCR can be repeated by using an aliquot from a previous PCR as the template. 相似文献
57.
Elghetany MT Molina CP Patel J Martinez J Schwab H Velagaleti GV 《Cancer Genetics and Cytogenetics》2002,136(1):38-42
Myelodysplastic syndromes (MDS) are associated with cell maturation defects that can manifest as abnormal surface antigen expression. We describe a patient with refractory anemia with excess blasts, who presented with infection and extensive dysplastic features in peripheral blood granulocytes. The granulocytes expressed CD11b, CD13, CD15, CD33, and CD43. The granulocytes also expressed CD4 antigen. Cytogenetic analysis showed a clonal t(5;12)(q33;p13). The patient improved on antibiotics with partial improvement in the dysplastic features. However, shortly after, the patient experienced paravertebral extramedullary blast transformation followed by a leukemia phase of acute monoblastic leukemia. The patient died a few days later. This is the first report describing anomalous expression of CD4 on granulocytes in MDS. Since the breakpoint on chromosome 12 is near the CD4 gene, which is mapped to 12p12, we hypothesize that dysregulation of the CD4 gene may have occurred resulting in its persistent expression on mature and maturing granulocytes. 相似文献
58.
Prestimulation-Induced Startle Modulation in Attention-Deficit Hyperactivity Disorder and Nocturnal Enuresis 总被引:3,自引:0,他引:3
Startle modulation was induced by prestimulation in 43, 6-11 year old boys with attention-deficit hyperactivity disorder (ADHD), 13 of whom were or had been enuretic, 17 age-matched enuretic boys, and 42 age-matched normal boys, using 60-ms and 120-ms prestimulation intervals and a 4000-ms continuous tone. There was a significant multivariate effect of enuresis on startle amplitude modulation. This effect was attributed primarily to the reduction of amplitude inhibition following the 120-ms prestimulation interval regardless of whether or not enuresis was associated with ADHD. There was no effect of ADHD on startle modulation by prestimulation. The inhibition following the 120-ms prestimulation interval in the enuretic boys was reduced to the level of 5-year-old normal children, suggesting a maturational component of the deficient startle inhibition. The neurophysiologic dysfunction underlying the deficient startle inhibition in enuresis, but not ADHD, is discussed in terms of a possible dysfunction of mesopontine reticular mechanisms mediating preattentive processing of signals associated with spinal reflexes involved in urinary bladder control. 相似文献
59.
Wedad Hanna Earl Silverman Lionel Boxaii Bernice R. Krafchik 《Ultrastructural pathology》1983,5(1):29-36
Epidermolysis bullosa (EB), a heterogeneous group of hereditary diseases, varies in mode of inheritance, extent, severity, and presence or absence of scarring and dystrophy. Fourteen cases (13 in infants and 1 in a young adult) were studied. Subtyping by ultrastructural findings in normal and blistered skin biopsies was as follows: EB simplex (2), EB letalis (3), EBD dominant (2), and EBD recessive (7). One case diagnosed as recessive dystrophic by electron microscopy (EM) followed a benign course with little scaring and was re-classified clinically and after reviewing the EM as dominant dystrophic. Defining the level of bulla formation by EM allowed accurate diagnosis of subtypes. In 6 patients with EBD recessive, normal and bullous skin showed collagenolysis and no anchoring fibrils. In patients with EBD dominant, rudimentary fibrils were noted in normal skin. Whether absence of anchoring fibrils is primary or secondary in these two types and the role of collagenolysis remain unresolved. 相似文献
60.
George Senyk Margaret Sharp Daniel P. Stites Lavelle Hanna Hermine Keshishyan Ernest Jawetz 《Medical microbiology and immunology》1980,168(2):91-101
Cell-mediated immunity (CMI) to chlamydial antigens was readily induced in guinea pigs by a single injection of Betaprone-inactivated chlamydiae in complete Freund adjuvant. The CMI was measured in vivo by delayed hypersensitivity skin tests, and in vitro by inhibition of migration of peritoneal exudate cells and by proliferation of lymph node lymphocytes. There was an overall correlation between in vivo and in vitro responses. Of the in vitro assays, migration inhibition reflected the state of sensitization, as judged by skin tests, more uniformly than lymphocyte stimulation. Extensive inter- and intra-species cross-reactivity was noted between LB-1, a strain ofC. trachomatis, and three strains ofC. psittaci, 6BC, GPIC, and 562F. Cross-reactivity between LB-1 and 6BC was one-way only, by all three parameters: LB-1 elicited strong cross-reactions in 6BC-immunized animals but not vice versa. Antichlamydial antibodies could not be demonstrated in any of the animals by microimmunofluorescence. 相似文献