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61.
Ogata T 《Medical molecular morphology》2005,38(4):243-250
Brush cells are widely distributed in the digestive and respiratory apparatus, but their function is still unknown. Because
brush cells (BC) are found in organs secreting NaHCO3, it was hypothesized that these cells may secrete NaHCO3. To test this possibility, rat common bile duct epithelia were examined by ultrastructural cytochemical methods for localizing
HCO3−, Cl−, and Na+ ions. All three ion precipitates were few in or on BCs of rats without stimulation. Lead carbonate precipitates, which localized
HCO3− ions by the lead nitrate-osmium method, increased markedly on the surface of the microvilli (MV) of BCs after secretin or
meal stimulation, but similar precipitates were few on the luminal surface of principal cells (PCs). Silver chloride precipitates,
which indicate the presence of Cl− ions by the silver-osmium method, increased in the apical cytoplasm and in MV of BCs after secretin or meal stimulation,
but they were few in PCs. Sodium pyroantimonate precipitates, which localize Na+ ions by the potassium pyroantimonate-osmium method, increased on the surface of the MV, along the basolateral membrane, and
in the apical cytoplasm of BCs after secretin or meal stimulation, but they were few in PCs. These results strongly suggest
that BCs may be a significant source of NaHCO3 secretion. 相似文献
62.
63.
F. Jaisser J. D. Horisberger B. C. Rossier 《Pflügers Archiv : European journal of physiology》1993,425(5-6):446-452
The cortical collecting tubule (CCT) of the mammalian kidney reabsorbs sodium and potassium, processes that are mediated by Na/K-ATPase and H/K-ATPase. CCT is also an important site for proton secretion, which is driven, in part, by H/K-ATPase. Na/K-ATPase and H/K-ATPase are members of the ion-motive P-ATPase gene family. They are closely related plasma membrane proteins which consist of heterodimers. The urinary bladder of the toad Bufo marinus is the amphibian counterpart of mammalian CCT. We have previously characterized a ouabain-resistant Na/K-ATPase [see ref. 17], from TBM cells, a clonal cell line derived from the toad bladder, which expresses transepithelial sodium transport. In the present study, we report the primary sequence and functional expression of a novel subunit (
bladder=
bl) isolated from a toad bladder epithelial cell cDNA library. The deduced polypeptide is 299 amino acids in length and has a predicted molecular mass of 33 kDa. The
bl protein exhibits 35% amino acid identity to the previously characterized
1 of B. marinus Na/K-ATPase and 39% identity with
3 of B. marinus Na/K-ATPase. It shares 38% identity with the mammalian gastric H/K-ATPase and 52% with the mammalian
2 Na/K-ATPase. Northern blot analysis shows that a 1.4×103-base mRNA is expressed at a high level in bladder epithelial cells and eye and at a trace level in kidney; it is not detectable in significant amounts in the stomach, colon and small intestine. The
bl subunit can associate with the
1 subunit of B. marinus Na/K-ATPase to form a functional sodium pump in the Xenopus laevis oocyte. Our data indicate that, in addition to the known
1 and
3 isoforms, a third distinct isoform of the subunit is present in the bladder epithelium. This new isoform could be functionally associated with subunits of either Na/K- or H/K-ATPase. 相似文献
64.
Bernd Sutor Walter Zieglgänsberger 《Pflügers Archiv : European journal of physiology》1987,410(1-2):102-111
Intracellular recordings were obtained from rat neocortical neurons in vitro. The current-voltage-relationship of the neuronal membrane was investigated using current- and single-electrode-voltage-clamp techniques. Within the potential range up to 25 mV positive to the resting membrane potential (RMP: –75 to –80 mV) the steady state slope resistance increased with depolarization (i.e. steady state inward rectification in depolarizing direction). Replacement of extracellular NaCl with an equimolar amount of choline chloride resulted in the conversion of the steady state inward rectification to an outward rectification, suggesting the presence of a voltage-dependent, persistent sodium current which generated the steady state inward rectification of these neurons. Intracellularly injected outward current pulses with just subthreshold intensities elicited a transient depolarizing potential which invariably triggered the first action potential upon an increase in current strength. Single-electrode-voltage-clamp measurements reveled that this depolarizing potential was produced by a transient calcium current activated at membrane potentials 15–20 mV positive to the RMP and that this current was responsible for the time-dependent increase in the magnitude of the inward rectification in depolarizing direction in rat neocortical neurons. It may be that, together with the persistent sodium current, this calcium current regulates the excitability of these neurons via the adjustment of the action potential threshold. 相似文献
65.
Objective and design: Myeloperoxidase (MPO) and proinflammatory cytokines play an important role in the development of inflammation. These markers
are generally measured using tedious ELISA procedures. In this study, a novel technique utilizing antibody conjugated quantum
dot nanoparticles was developed to detect Myeloperoxidase, Interleukin-1α (IL-1α) and Tumor Necrosis Factor-α (TNF-α) in vivo in the dextran sodium sulfate (DSS) model of experimental colitis.
Materials and methods: Colitis was induced in animals (n = 8 animals/group) by feeding 4% DSS solution ad libitum for seven to eight days. Quantum Dots (QDs) exhibiting fluorescence at various wavelengths were conjugated to MPO, IL-1α
and TNF-α polyclonal antibodies and tested in vivo at various stages of colitis. Tissue sections obtained were imaged with confocal microscope. The image intensity obtained
from the tissue specimen was correlated with clinical activity measured as Disease Activity Index (DAI).
Results: Myeloperoxidase, IL-1α and TNF-α were visualized with quantum dots on various days of disease. The intensity of quantum dots
increased with the increase in inflammation. The increase in intensity showed an excellent correlation with the DAI based
on the clinical parameters.
Conclusion: The study demonstrated that multiple biomarkers can be detected simultaneously and their quantitative expression correlated
well with clinical disease severity. This novel technology should facilitate design of a novel optical platform for imaging
various biomarkers of inflammation, early detection of acute and chronic disease markers and inflammation-mediated cancer
markers. This detection may also facilitate determination of therapeutic success.
Received 14 March 2007; returned for revision 8 May 2007; accepted by M. Parnham 27 June 2007 相似文献
66.
R. -M. Jolidon MD H. Knecht L. Humair A. de Torrente 《Journal of molecular medicine (Berlin, Germany)》1991,69(8):340-344
Summary A young man who had suffered several episodes of deep-vein thrombosis of the legs since the age of 20 had a myocardial infarction at the age of 33, at which time both a prolonged partial thromboplastin time (PTT), compatible with a lupus anticoagulant (LA), and decreased fibrinolytic capacity (FC) were found.His sister presented with deep-vein thrombosis of a leg and subsequent pulmonary embolism when she was 18 years old. She had a miscarriage three years later and developed a hemolytic-uremic syndrome at the age of 35. The PT and FC were normal. Laboratory investigations of the parents revealed positive antinuclear antibodies in the mother's serum but no anomaly in the father.This study suggests a familial tendency to develop autoimmune disorders associated with LA and thromboembolic complications related to decreased FC. 相似文献
67.
Kamran Sardari 《Comparative clinical pathology》2007,16(2):97-102
Local injection of a mixture of beta-aminopropionitril fumarate (BAPN-f) and sodium hyaluronate (NaH+) together with controlled exercise were evaluated for treatment of superficial digital flexor tendon (SDFT) injuries in horses.
Fourteen mixed breed horses with subacute SDF tendon injuries in forelimbs were randomly assigned to two groups. One group
received BAPN-f (0.7 mg/ml) and the other received NaH+ (10 mg/ml) all by intratendinous injection. Controlled exercise started during the first week after intratendinous treatment
and continued for 12 weeks. Cross-sectional area (CSA) of the SDFT, diameter of the SDFT, and relative area of the lesion
(presence of CSA) were measured by ultrasonographic examination. Lesions were semiquantitatively graded for echogenicity on
a scale of 0 to 4. The lesion severity in CSA was significantly reduced by BAPN and NaH compared to those horses treated by
BAPN only (p < 0.05). Lesion echogenicity score was significantly higher in horses treated with BAPN and NaH+ at day 0 compared to horses treated with BAPN (p < 0.05). At the end of the study, lesion echogenicity score was significantly reduced in the horses treated with BAPN and
NaH+ compared to horses treated by BAPN only (p < 0.05). According to the results of the present study, a combination of BAPN-f and NaH+ has a greater beneficial effect on tendon healing and remodeling in horses, as assessed by sonographic examination, compared
to treatment with single drugs. 相似文献
68.
Drago F Frisina M Grech M Nicolosi A Micale V Nicosia A Medico M Foti F 《Neuroscience letters》2001,300(3):176-178
Melatonin affects the circadian sleep/wake cycle, but it is not clear whether it may influence drug-induced narcosis. Sodium thiopenthal was administered intraperitoneally into male rats pre-treated with melatonin (0.05, 0.5, 5 and 50 mg/kg). Melatonin pre-treatment affected in a dual manner barbiturate narcosis, however, no dose-effect correlation was found. In particular, low doses reduced the latency to and prolonged the duration of barbiturate narcosis. In contrast, the highest dose of melatonin (50 mg/kg) caused a paradoxical increase in the latency and produced a sustained reduction of the duration of narcosis, and a reduction in mortality rate. Melatonin 0.5 and 5 mg/kg influenced the duration but not the latency of ketamine- or diazepam-induced narcosis. Thus, the dual action of melatonin on pharmacological narcosis seems to be specific for the barbiturate mechanism of action. 相似文献
69.
Miscarriage rates following in-vitro fertilization are increased in women with polycystic ovaries and reduced by pituitary desensitization with buserelin 总被引:3,自引:10,他引:3
Balen Adam H.; Tan Seang-Lin; MacDougall Jane; Jacobs Howard S. 《Human reproduction (Oxford, England)》1993,8(6):959-964
To assess the risk of miscarriage after in-vitro fertilization(IVF) with respect to age, cause of infertility, ovarian morphologyand treatment regimen, a retrospective analysis was performedof the first 1060 pregnancies conceived between June 1984 andJuly 1990 as a result of 7623 IVF cycles. Superovulation inductionwas achieved with human menopausal gonadotrophin (HMG) and/orpurified follicle stimulating hormone (FSH) together with eitherclomiphene citrate or the gonadotrophin hormone-releasing hormone(GnRH) agonist buserelin, the latter either as a short flareregimen or as a long regimen to induce pituitarydesensitization. There were 282 spontaneous abortions (26.6%)and 54 ectopic pregnancies (5.1%). The mean age of women withongoing pregnancies was 32.2 (SD 3.9) years compared with 33.2(SD 4.1) years in those who miscarried, which were significantlydifferent (P = 0.008). There was no relation between the miscarriagerate and the indication for IVF. The miscarriage rate was 23.6%in women with normal ovaries compared with 35.8% in those withpolycystic ovaries [P = 0.0038, 95% confidence interval (CI)4.6823.10%]. There was no difference in the miscarriagerate between treatment with HMG or FSH. Women whose ovarieswere normal on ultrasound were just as likely to miscarry ifthey were treated with clomiphene or with the long buserelinprotocol. Those with polycystic ovaries, however, had a significantreduction in the rate of miscarriage when treated with the longbuserelin protocol, 20.3% (15/74), compared with clomiphenecitrate, 47.2% (51/108) (P = 0.0003, 95% CI 13.8240.09%). 相似文献
70.
Histidine-rich protein genes and their transcripts in Plasmodium falciparum and P. lophurae 总被引:2,自引:0,他引:2
M Wallach D F Cully L O Haas W Trager G A Cross 《Molecular and biochemical parasitology》1984,12(1):85-94
The presence of histidine-rich protein (HRP) related genes and gene products in Plasmodium falciparum was demonstrated using a synthetic pentahistidine-encoding oligonucleotide and a cloned HRP cDNA probe prepared from the avian parasite P. lophurae. In Northern blotting experiments, two knobby clones of P. falciparum were found to contain a 3500 nucleotide RNA species that hybridized with the oligonucleotide and HRP cDNA probes. As this component had the expected size for an mRNA encoding an 80-90 kDa protein and was absent from two knobless clones of P. falciparum, we concluded that it represented a 'knob protein' mRNA. Using the restriction enzyme EcoRI, three identical cross-hydribizing HRP gene fragments were found in the DNA of both knobby and knobless clones of P. falciparum. These fragments differed in size from those present in P. lophurae. These results suggest that the absence of knob protein mRNA in knobless clones is not due to loss of the corresponding gene(s). 相似文献