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121.
Effect of stretch on calcium channel currents recorded from the antral circular myocytes of guinea-pig stomach 总被引:7,自引:0,他引:7
Wen Xie Xu Sung Joon Kim Sang Jeong Kim Insuk So Tong Mook Kang Jong Chul Rhee Ki Whan Kim 《Pflügers Archiv : European journal of physiology》1996,432(2):159-164
The effect of membrane stretch on voltage-activated Ba2+ current (I
Ba) was studied in antral circular myocytes of guinea-pig using the whole- cell patch-clamp technique. The changes in cell volume
were elicited by superfusing the myocytes with anisosmotic solutions. Hyposmotic superfusate (202 mosmol/l) induced cell swelling
and increased peak values of I
Ba at 0 mV (from −406.6 ± 45.5 pA to −547.5 ± 65.6 pA, mean ± SEM, n = 8) and hyperosmotic superfusate (350 mosmol/l) induced cell shrinkage and decreased peak values of I
Ba at 0 mV (to −269.5 ± 39.1 pA, n = 8). Such changes were reversible and the extent of change was dependent on the osmolarity of superfusate. The values of
normalized I
Ba at 0 mV were 1.43 ± 0.04, 1.30 ± 0.06, 1.23 ± 0.04, 1.19 ± 0.04, 1 and 0.68 ± 0.06 at 202, 220, 245, 267, 290 and 350 mosmol/l,
respectively (n = 8). I
Ba was almost completely blocked by nicardipine (5 μM) under hyposmotic conditions. The values of steady-state half-inactivation
voltage (−37.7 ± 3.3 and −36.5 ± 2.6 mV, under control and hyposmotic conditions, respectively) or the half-activation voltage
(−13.6 ± 2.3 and −13.9 ± 1.9 mV) of I
Ba were not significantly changed (P > 0.05, n = 6). Cell membrane capacitance was slightly increased from 50.00 ± 2.86 pF to 50.22 ± 2.82 pF by a hyposmotic superfusate
(P < 0.05, n = 6). It is suggested that cell swelling increases voltage-operated L-type calcium channel current and that such a property
is related to the response of gastric smooth muscle to mechanical stimuli.
Received: 14 November 1995/Received after revision and accepted: 8 January 1996 相似文献
122.
目的 研究双色间期荧光原位杂交 (I-FISH)技术监测CML治疗过程中肿瘤细胞负荷的灵敏度及特异性。方法 应用I-FISH、常规细胞遗传学 (CCG)G显带技术和筑巢式逆转录聚合酶链式反应 (RT -PCR)技术对 2 0例治疗中CML患者骨髓中的肿瘤负荷进行检测。结果 对照组骨髓细胞假阳性率为 0 6 %~2 0 % ,分界值为 2 4 5 % ;2 0例患者经IFN -α治疗或骨髓移植后 9/18例(5 0 % )CCG检测到Ph( )细胞 ,阳性细胞率 16 7%~ 10 0 % ;结合正常分界值 ,16 /2 0例 (80 % )经I-FISH检测到BCR -ABL( )肿瘤细胞 ,阳性细胞率 2 8%~ 99 6 %。 16例患者行RT -PCR检查 ,13/16例 (81 3% )融合基因转录本阳性。结论 I -FISH技术可高度灵敏、特异地监测CML患者治疗过程中肿瘤细胞负荷的变化 ,与CCG及RT -PCR相比 ,检测所得结论更加科学、合理和具有说服力。 相似文献
123.
124.
K. Johani B.G. Fritz T. Bjarnsholt B.A. Lipsky S.O. Jensen M. Yang A. Dean H. Hu K. Vickery M. Malone 《Clinical microbiology and infection》2019,25(3):332-339
Objectives
Rigorous visual evidence on whether or not biofilms are involved in diabetic foot osteomyelitis (DFO) is lacking. We employed a suite of molecular and microscopic approaches to investigate the microbiome, and phenotypic state of microorganisms involved in DFO.Methods
In 20 consecutive subjects with suspected DFO, we collected intraoperative bone specimens. To explore the microbial diversity present in infected bone we performed next generation DNA sequencing. We used scanning electron microscopy (SEM) and peptide nucleic acid fluorescent in situ hybridization (PNA-FISH) with confocal microscopy to visualize and confirm the presence of biofilms.Results
In 19 of 20 (95%) studied patients presenting with DFO, it was associated with an infected diabetic foot ulcer. By DNA sequencing of infected bone, Corynebacterium sp. was the most commonly identified microorganism, followed by Finegoldia sp., Staphylococcus sp., Streptococcus sp., Porphyromonas sp., and Anaerococcus sp. Six of 20 bone samples (30%) contained only one or two pathogens, while the remaining 14 (70%) had polymicrobial communities. Using a combination of SEM and PNA-FISH, we identified microbial aggregates in biofilms in 16 (80%) bone specimens and found that they were typically coccoid or rod-shaped aggregates.Conclusions
The presence of biofilms in DFO may explain why non-surgical treatment of DFO, relying on systemic antibiotic therapy, may not resolve some chronic infections caused by biofilm-producing strains. 相似文献125.
Numerical chromosomal aberrations in prostate cancer: correlation with morphology and cell kinetics 总被引:3,自引:0,他引:3
Rolf -Peter Henke Eva Krüger Nebahat Ayhan Dirk Hübner Peter Hammerer 《Virchows Archiv : an international journal of pathology》1993,422(1):61-66
Eleven routinely processed radical prostatectomy specimens were studied for the presence of numerical chromosomal aberrations by means of in situ hybridization with nucleic acid probes specific for chromosomes 7, 10, 17, X, and Y. Cytogenetic information was correlated with morphology, tumour stage and volume as well as with cell kinetics, the latter being assessed by immunohistochemistry with antibodies raised against the proliferative cell nuclear antigen (PCNA) and against a formalin-resistant epitope of the Ki-67 antigen, MIB 1. In 5 of 11 cases, numerical aberrations of at least one chromosome were found. The cases with normal chromosome numbers were those with the smallest volumes of Gleason grade 4 and/or 5 tumour (mean 0.5 cm3) and represented tumours restricted to the prostate. Tumours with aberrations in the number of detected chromosomes showed advanced stages and large volumes of high-grade tumour (mean 12.5 cm3). All 4 tumours with positive surgical margins were recruited from a group with marked local heterogeneity in chromosome numbers. Immunostaining with MIB 1 and PCNA was most intense in areas of high-grade tumour and was positively correlated with the emergence of chromosomal aberrations. The data suggest that the appearance of numerical chromosomal aberrations in prostate cancer coincides with aggressive tumour behaviour and could be used as an additional prognostic marker.This work is part of E.K.'s doctoral thesis 相似文献
126.
Hunter S Weiss S Ou CY Jaye D Young A Wilcox J Arbiser JL Monson D Goldblum J Nolen JD Varma V 《Human pathology》2005,36(9):987-993
Apolipoprotein D (apoD) expression was studied in nonneoplastic peripheral nerve, neurofibromas (NFs), and malignant peripheral nerve sheath tumors (MPNSTs) by quantitative polymerase chain reaction, in situ hybridization, and immunohistochemistry. Multiplex quantitative polymerase chain reaction for messenger RNA was performed on a series of formalin-fixed and paraffin-embedded specimens that included 9 MPNSTs, 12 NFs, and 4 normal peripheral nerves. The average apoD expression was 108-fold decreased (DeltaCt = -7.3) in the MPNSTs compared with the NFs (P < .05). ApoD expression levels were 3.0-fold elevated (DeltaCt = 1.7) in the NFs compared with nonneoplastic peripheral nerve (P < .05). In situ hybridization for apoD RNA was performed on a separate series of 10 cases in which each microscopic section included both MPNST and the NF from which it arose. These studies confirmed elevated apoD expression in NFs compared with MPNSTs and demonstrated that this expression was variable among individual cells within the NFs. Differential expression by immunohistochemistry could only be demonstrated in selected areas, most likely because apoD protein is a small molecule that is secreted out of the cell into the extracellular space and plasma. ApoD expression initially increases a small amount with the formation of NFs from nonneoplastic peripheral nerve and subsequently decreases markedly as NFs transform into MPNSTs. This expression pattern may serve as a marker for cell cycle inhibition during peripheral nerve tumorigenesis. 相似文献
127.
Using electrophysiological and radiotracer studies in parallel, we have investigated the characteristics of the endogenous Na+-dependent amino acid transporter (system B0,+) in Xenopus oocytes with regard to ion dependence, voltage dependence and transport stoichiometry. In voltage-clamped oocytes (–60 mV) superfusion with saturating concentrations of amino acids (1 mM) in 100 mM NaCl resulted in reversible, inward currents (mean±SEM): alanine, 1.83±0.09 nA (n=21); arginine, 2.54±0.18 nA (n=17); glutamine, 1.73±0.10 nA (n=19). Only arginine evoked a current in choline medium (0.50±0.13 nA, n=10), whereas Cl– replacement had no effect on evoked currents. The glutamine-evoked current was saturable (I
max=1.73 nA, glutamine K
m=0.12 mM) and linearly dependent upon voltage between –90 and –30 mV. Using direct and indirect (activation) methods, we found that transport can proceed with Na+/amino acid coupling stoichiometry of either 11 or 21, but coupling was the same for each amino acid tested (alanine, arginine and glutamine) within a batch of oocytes (i.e. from a single toad). Despite the net single positive charge on arginine, the magnitude of the net transmembrane charge movement during Na+-coupled arginine transport was identical to that for the zwitterionic neutral amino acids glutamine and alanine; this may be explained by a concomitant stimulation of K+ efflux during arginine transport with a putative coupling of 1 K+1 arginine. 相似文献
128.
Lateral association of sphingolipids and cholesterol is considered to form membrane microdomains such as “lipid rafts” obtainable as a detergent-resistant membrane microdomain (DRM) fraction after solubilization with a non-ionic detergent and density gradient centrifugation. Since not only sphinogolipids and cholesterol, but also functional lipids such as phosphatidylinositol 4,5-bisphosphate (PIP2) are reported to be localized in DRM prepared from several cultured cells, this domain is considered to be a platform mediating lipid-signaling. Although PIP2 is considered to have pivotal roles in the nervous system, little information is available on the localization of PIP2 in the DRM within the synaptic plasma membrane (SPM) obtained from matured rat brains. In this study, in order to know the localization of PIP2 in SPM-derived DRM, we measured the amount of PIP2 in SPM and SPM-derived DRM, by the thin-layer chromatography blotting method, using a GST-fusion protein of the pleckstrin-homology domain of phospholipase Cδ1 as a PIP2 binding probe. About 10% of the PIP2 in SPM was recovered in DRM. In contrast, over 40% recovery was observed for the membrane cholesterol and sphingomyelin, and about 30% recovery was observed for phosphatidylcholine, phosphatidylethanolamine, and phosphatidylserine in the DRM were detected using the thin-layer chromatography method. Since the recovery of proteins in DRM was about 10%, the result indicates that there occurs no enrichment of PIP2 in DRM prepared from SPM. 相似文献
129.
Fumitaka Saji Yoshihiro Tokugawa Shoji Kamiura Yoshihiro Samejima Kazutomo Ohashi Chihiro Azuma Osamu Tanizawa 《Journal of clinical immunology》1989,9(5):409-414
The seroprevalence rate of human T-cell leukemia virus type I (HTLV-I) in pregnant women in the Osaka district was determined by enzyme-linked immunosorbent assay and Western blot analysis. Twenty-one (1.0%) of 2192 samples tested were positive for both assays and the seropositive parturients were found to be integrated with HTLV-I proviral DNA in their mononuclear cells by a DNA dot blot hybridization assay using HTLV-I DNA probe or by a selective DNA amplification technique using the polymerase chain reaction (PCR). On the other hand, proviral DNA was not detected in cord blood of the neonates born to the carrier mothers, indicating that transplacental infection of HTLV-I during pregnancy could be excluded. The results support the hypothesis that postpartum infection via breast milk plays a significant role among the possible perinatal transmission routes. 相似文献
130.
Molecular identification of a novel human rotavirus in relation to subgroup and electropherotype of genomic RNA 总被引:3,自引:0,他引:3
O Nakagomi H Oyamada S Kuroki Y Kobayashi A Ohshima T Nakagomi 《Journal of medical virology》1989,28(3):163-168
A total of 41 stool rotavirus specimens collected from children with acute diarrhea at four different locations in Akita Prefecture, Japan, during the peak of the winter diarrhea epidemic in 1988 were analyzed by polyacrylamide gel electrophoresis of viral RNA in conjunction with subgrouping assay. We found that a single strain predominated, with cocirculating strains with less common electropherotypes at a given location, and that two different strains could predominate at geographically close but different locations even during a very limited time of the epidemic season. Furthermore, we isolated a human rotavirus strain (AU125) that was similar to the AU-1 strain in that it possessed a long RNA pattern yet belonged to subgroup I. Genetic analysis by RNA-RNA hybridization assay indicated that the AU125 strain was distinct from two previously identified human rotavirus gene groups (genogroups) represented by the Wa strain (subgroup II with long RNA electropherotype) and the DS-1 strain (subgroup I with short RNA electropherotype), but was very closely related to the AU-1 strain. These data suggest that the genetic diversity of human rotaviruses may be more extensive than was previously thought. 相似文献