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61.
62.
There is increasing evidence that immunological mechanisms play a role in the pathogenesis and pathophysiology of endometriosis. It was therefore of interest to study interleukin-8 (IL-8), a chemokine, in the peritoneal fluid and peripheral blood of women undergoing laparoscopic procedures. The presence and concentrations of IL-8 in relation to endometriosis, infertility and abdominal pain were evaluated. Samples of peritoneal fluid (n = 49) and peripheral blood (n = 50) were obtained from 50 consecutive patients undergoing laparoscopic surgery for various gynaecological indications (abdominal pain, infertility, sterilization). IL-8 was present in the peritoneal fluid of most women (87%). The concentration of IL-8 in the peritoneal fluid was higher in women with endometriosis compared to women without (P = 0.02). This difference was more pronounced in early (stage 1) endometriosis (P = 0.001). IL-8 concentrations in the peritoneal fluid were also higher in women with early endometriosis compared to women with later stages of the disease (P = 0.003). Peripheral blood concentrations did not correlate with peritoneal fluid concentrations of IL-8 and/or the presence of endometriosis. We conclude that IL-8 is an important factor that may contribute to the pathogenesis of endometriosis possibly by promoting neovascularization. This information can be a guide in the development of new therapeutic approaches for the treatment of endometriosis.   相似文献   
63.
The authors examined 10 patients with Gerstmann-Sträussler syndrome or Creutzfeldt-Jakob disease and 10 with Alzheimer''s disease (AD). Immunohistochemistry using anti-prion protein (PrP) and anti-beta/A4 protein (beta/A4) coupled with formic acid pretreatment could detect Congophilic and non-Congophilic deposits. Prion protein deposits were classified into five types and compared with types of beta/A4 deposits. Kuru plaques with multicentric cores and fine granular deposits were a characteristic feature of PrP deposits. Some types of PrP or beta/A4 deposits depend on the anatomic sites. To clarify the relationship of microglia and astrocytes to PrP or beta/A4 deposits, double-immunostaining method was performed. In both kuru and senile plaques, microglia were closely linked to the Congophilic plaques. Astrocytes, however, extended their processes toward the plaques even in the non-Congophilic plaques. These observations strongly suggest that similar glial association with plaque formation may be involved in both kuru and senile plaques, although the amyloid core proteins differ.  相似文献   
64.
Effects of Lentinan on Cytotoxic Functions of Human Lymphocytes   总被引:1,自引:0,他引:1  
The in vitro effects of lentinan on natural killer (NK), antibody-dependent cell-mediated cytotoxicity (ADCC), lectin-dependent cell-mediated cytotoxicity (LDCC) and mitogen-induced blast transformation were studied in patients with solid tumors and chroyic lymphocytic leukemia (CLL). NK activity was measured against Cr-labelled K-562 targets, ADCC against antibody-coated chicken red cells. LDCC and natural cell-mediated cytotoxicity (NCMC) was assessed using 3H-thymidine prelabelled HEp-2 targets. Mitogen (PHA-and Con A-) induced blast transformation was measured by thymidine incorporation.

Blastogenesis and LDCC was not influenced by lentinan. 1 μg/ml lentinan increased NCMC of tumor-bearing subjects. The most prominent enhancement of NK and ADCC activity was seen in CLL patients, where a dose-related increase was seen (from 0.01 to 1 μg/ml).  相似文献   
65.
A new mutation in the serine-threonine klnase domain of the transforming growth factor β type II receptor (TGFpRII) was found in a case of diffuse, B cell non-Hodgkin's lymphoma of the stomach. A mfssense mutation (ACA to GCA, Thr to Ala) was detected In exon 5, and a wild type allele was also present. This Is the first naturally occurring mutation in the klnase domain of this gene identified in human primary lymphoma. The replication error at three loci was negative, and the poly A tract of exon 3, which is frequently a target of mismatch repair genes, was intact. Malignant lymphoma of B cell origin in the stomach Is an addition to an expanding catalogue of tumors with TGFβRII alterations, and the biological sequelae of the change in the functional domain and the clinical characteristics of the patient in this study are intriguing.  相似文献   
66.
1. Horizontal cells of the cat retina were isolated by enzymatic dissociation. Two types of horizontal cells were identified: the axonless (A-type) horizontal cell having four to six thick, long (approximately 100 microns) dendrites, and the short-axon (B-type) horizontal cell having many (> 5) fine, short (approximately 30 microns) dendrites. 2. Membrane properties of isolated horizontal cells were analyzed under current-clamp and voltage-clamp conditions. In the A-type cell, the average resting potential was -55 mV and the mean membrane capacitance was 110 pF, whereas values in the B-type cell were -58 mV and 40 pF, respectively. The A-type cell showed long-lasting Ca spikes, but B-type cells had no Ca spikes. 3. Five types of voltage-dependent ionic currents were recorded: a sodium current (INa), a calcium current (ICa), and three types of potassium currents. Potassium currents consisted of potassium current through the inward rectifier (Ianomal), transient outward potassium current (IA), and potassium current through the delayed rectifier (IK(v)). INa was recorded only from A-type cells. Other currents were recorded from both types of cells. 4. INa activated when cells were depolarized from a holding potential (Vh) of -95 mV, and it was maximal at -25 mV. This current was blocked by tetrodotoxin. Approximately half of the A-type cells had INa, but no B-type cell had this current. 5. L-type ICa, an inward-going sustained current, was activated with depolarization more positive than -25 mV. Current amplitude reached a maximal value near 15 mV and became smaller with further depolarization.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
67.
Loop-mediated isothermal amplification (LAMP) is a novel nucleic acid amplification method in which reagents react rapidly and efficiently, with a high specificity, under isothermal conditions. We used a LAMP assay for the detection of herpes simplex virus type 1 (HSV-1), herpes simplex virus type 2 (HSV-2), and varicella-zoster virus (VZV). The virus specificities of primers were confirmed by using 50 HSV-1, 50 HSV-2, and 8 VZV strains. The assay was performed for 45 min at 65 degrees C. The LAMP assay had a 10-fold higher sensitivity than a PCR assay. An analysis of nucleotide sequence variations in the target and primer regions used for the LAMP assay indicated that 3 of 50 HSV-1 strains had single nucleotide polymorphisms. No HSV-2 or VZV strains had nucleotide polymorphisms. Regardless of the sequence variation, there were no differences in sensitivity with the HSV-1-specific LAMP assay. To evaluate the application of the LAMP assay for clinical diagnosis, we tested clinical samples from 40 genital herpes patients and 20 ocular herpes patients. With the LAMP assay, 41 samples with DNA extraction and 26 direct samples without DNA extraction were identified as positive for HSV-1 or HSV-2, although 37 samples with DNA extraction and just one without DNA extraction were positive by a PCR assay. Thus, the LAMP assay was less influenced than the PCR assay by the presence of inhibitory substances in clinical samples. These observations indicate that the LAMP assay is very useful for the diagnosis of HSV-1, HSV-2, and VZV infections.  相似文献   
68.
The transient receptor potential canonical type 5 (TRPC5) channel is a member of the channels that has been implicated in neurite extension and growth cone morphology of hippocampal neurons. Although homomeric TRPC5 channels are activated following stimulation of Gq/11-coupled receptors, the exact mechanism for this activation remains unresolved. Using two-electrode voltage clamp recordings, we show that the activity of TRPC5 channels expressed in Xenopus oocytes is dependent on the presence of Ca2+ at the extracellular as well as the cytoplasmic side of the plasma membrane. TRPC5 was activated by the stimulation of coexpressed M5 muscarinic receptors or by ionomycin. The TRPC5 activity was detectable with the presence of submillimolar levels of extracellular Ca2+, but it was eliminated by the injection of 5 mM 1,2-bis(o-aminophenoxy)ethane-N,N,N,N-tetraacetic acid into the oocytes. Lanthanum could substitute for extracellular Ca2+ to support TRPC5 activity. Coexpression of Ca2+-binding protein 1 (CaBP1), but not calmodulin (CaM), inhibited the TRPC5 activity, without affecting the cell surface expression of TRPC5 proteins. Using in vitro binding assays, we demonstrated direction interactions between CaBP1 and TRPC5. The CaBP1-binding sites at the C terminus of TRPC5 are closely localized, but not identical, to CaM-binding sites. We conclude that TRPC5 is a Ca2+-regulated channel, and its activity is negatively controlled by CaBP1.  相似文献   
69.
1. Single neurons in the abducens nucleus were recorded extracellularly in alert rhesus macaques trained to make a variety of eye movements. An abducens neurons was identified as a motoneuron (MN) if its action potentials triggered an averaged EMG potential in the lateral rectus muscle. Abducens internuclear neurons (INNs) that project to the oculomotor nucleus were identified by collision block of spontaneous with antidromic action potentials evoked with a stimulating electrode placed in the medial rectus subdivision of the contralateral oculomotor nucleus. 2. All abducens MNs and INNs had qualitatively similar discharge patterns consisting of a burst of spikes for lateral saccades and a steady firing whose rate increased with lateral eye position in excess of a certain threshold. 3. For both MNs and INNs the firing rates associated with different, constant eye positions could be described accurately by a straight line with slope, K (the eye position sensitivity in spikes.s-1.deg-1), and intercept, T (the eye position threshold for steady firing). For different MNs, K increased as T varied from more medial to more lateral values. In contrast, the majority of INNs already were active for values of T more medial than 20 degrees and showed little evidence of recruitment according to K. 4. During horizontal sinusoidal smooth-pursuit eye movements, both MNs and INNs exhibited a sinusoidal modulation in firing rate whose peak preceded eye position. From these firing rate patterns, the component of firing rate related to eye velocity, R (the eye velocity sensitivity in spikes.s-1.deg-1.s-1), was determined. The R for INNs was, on average, 78% larger than that for MNs. Furthermore, R increased with T for MNs, whereas INNs showed no evidence of recruitment according to R. If, as in the cat, the INNs of monkeys provide the major input to medial rectus MNs and if simian medial rectus MNs behave like our abducens MNs, then recruitment order, which is absent in INNs, must be established at the MN pool itself. 5. Unexpectedly, the R of MNs decreased with the frequency of the smooth-pursuit movement. Furthermore, the eye position sensitivity, K, obtained during steady fixations was usually less than that determined during smooth pursuit. Therefore, conclusions about the roles of MNs and premotor neurons based on how their R and K values differ must be viewed with caution if the data have been obtained under different tracking conditions.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
70.
Centromere protein F (CENP-F) expression (localization and characteristics) in relation to tumor clinicopathological parameters was immunohistochemically examined and evaluated in 47 archival biopsy specimens of buccal and gingival squamous cell carcinomas (SCC). Centromere protein F expression was detected in 79% of the samples. An increase in the labeling index (LI) with WHO grading was obtained ( P  < 0.05). Correlations were obtained between the CENP-F LI and tumor size ( P  < 0.05). Immunoelectron microscopy showed CENP-F nuclear staining as punctate or fine dots. The present study shows that CENP-F expression and detection of a more specific cell subpopulation presents a theoretical advantage for the analysis of the precise cell cycle of G2 to M cells, compared to Ki-67.  相似文献   
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