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51.
52.
We examined the possibility that lumbar skin warming can increase gastrointestinal motility by investigating the electrogastrogram (EGG), blood pressure, and heart rate with psychometric ratings in healthy humans. Scores of mood state profiles showed that lumbar skin warming (42 degrees C, 20 min) decreased tension-anxiety, depression, anger-hostility, fatigue, and confusion of the participants. A multiple bandpass filter analysis of EGGs showed that a postural transition from orthostatic to supine for measurement caused an increase in dominant frequency of 25-29% towards the frequencies of the normal interdigestive migrating motor complex (IMC). The spectral power of the IMC band, 2.55-3.05 cycles/min, was increased by 20 min-warming, reflecting the increase in gastric contractility. No increase in the spectral power was observed in the time-matched control group without skin warming. Therefore, an increase in contractility is a characteristic of lumbar skin warming. The systolic blood pressure increased by 15% during warm stimulation. Interbeat intervals were not influenced by warm stimulation. An analysis of interbeat intervals by a fast Fourier transform method showed that the cardiac sympathetic and parasympathetic nerves did not play a major role in raising the blood pressure. Vasoconstriction of the mesenteric artery was therefore considered to cause a blood pressure increase during warming. It is hypothesized that vasoconstriction of the visceral arteries by lumbar skin warming increases the blood pressure and gastrointestinal contractility.  相似文献   
53.
Gaps and fragmentation of the superficial lymph node cortex are considered to provide intranodal shunt flow between the afferent and efferent vessels. Using serial sections of 205 nodes obtained from 27 donated cadavers more than 70 years of age, we examined the histological architecture of the abdominal and pelvic nodes in elderly Japanese. Secondary follicles were rare in the specimens. Cortex gaps were, to a greater or lesser degree, found in all nodes. We classified these nodes into three types according to how often the gap occurred. Type 1 nodes, with a relatively complete shield for the afferent lymph, were most frequently found in gastric nodes, whereas type 3 nodes, with numerous gaps, were often observed in the colic, para-aortic and pelvic nodes. The type 3 nodes showed a specific architecture characterized by a fragmented superficial cortex, three-dimensionally assembled cords and a common sinus between them. Primary follicles were located in the assembled cord structures as well as at the superficial cortex. Irrespective of the type, B and T lymphocyte areas were intermingled in the cortex-like areas. The present results reveal region-specific histological heterogeneity in aged human visceral nodes. Due to increased surface areas, the type 3 architecture seemed to accelerate systemic immunity rather than act as a local barrier in the para-aortic and pelvic nodes, which are located centrally along the lymphatic drainage routes. However, thick trabeculae often seemed to develop in the type 3 sinus to decrease nodal function with aging.  相似文献   
54.
The gene Bcl11b, which encodes zinc finger proteins, and its paralog, Bcl11a, are associated with immune-system malignancies. We have generated Bcl11b-deficient mice that show a block at the CD4-CD8- double-negative stage of thymocyte development without any impairment in cells of B- or gammadelta T cell lineages. The Bcl11b-/- thymocytes showed unsuccessful recombination of V(beta) to D(beta) and lacked the pre-T cell receptor (TCR) complex on the cell surface, owing to the absence of Tcrb mRNA expression. In addition, we saw profound apoptosis in the thymus of neonatal Bcl11b-/- mice. These results suggest that Bcl11b is a key regulator of both differentiation and survival during thymocyte development.  相似文献   
55.
We developed a highly sensitive enzyme immunoassay (EIA), the p-AP/HHTIO method, that detects serum hepatitis B surface antigen (HBsAg) by measuring stabilized nitroxide radicals using a novel electron spin resonance technique [Matsuo et al. (1998) Free Radic Biol Med 25:929-935]. To demonstrate the clinical significance of this method and to reveal occult hepatitis B virus (HBV) infection in patients, we used the method to analyze serum samples of 30 patients with acute or fulminant hepatitis who were negative for HBsAg by standard EIA, and those of seven chronic HBV carriers who became negative for HBsAg during a follow-up period by standard EIA. We also examined serum HBV DNA by amplification of the HBV S gene, using the polymerase chain reaction (PCR) technique. The p-AP/HHTIO method showed that 9 of 20 (45%) patients with acute hepatitis and 2 of 10 (20%) with fulminant hepatitis were positive for HBsAg; PCR detected HBV DNA in these HBsAg-positive patients. Antibody against hepatitis B core antigen was detected in one patient with fulminant hepatitis. The p-AP/HHTIO method demonstrated prolonged seropositivity of HBsAg even after standard EIA showed a loss of HBsAg in all seven HBV carriers. Our p-AP/HHTIO method is useful for screening and diagnosing HBV infection in patients with liver diseases who are negative for conventional HBV-related serological markers.  相似文献   
56.
Synphilin-1 represents a cytoplasmic protein that interacts with α-synuclein and localizes close to synaptic vesicles. The interaction of synphilin-1 with several proteins involved in Parkinson's disease suggests that it might be involved in the pathogenesis of the disease. Nonetheless, the function of synphilin-1 remains unclear. In the present study, we generated transgenic mice expressing human synphilin-1 under the prion protein promoter. Synphilin-1 was widely expressed in neurons in the brain including the substantia nigra, where massive loss of dopamine neurons was not observed. In the transgenic mouse brain, synphilin-1 protein was polyubiquitinated, and partially insoluble. Although modified-SHIRPA revealed no significant difference in behavior and morphology, the reduced rotarod performance and step length were observed in transgenic mice as compared with non-transgenic littermates. Synphilin-1 might be involved in motor function, and its accumulation in the central nervous system can cause motor impairments.  相似文献   
57.
58.
Our previous studies in mice showed that the nonmyeloablative conditioning regimen of fractionated irradiation of the lymphoid tissues (total lymphoid irradiation; TLI) and depletive anti-T-cell antibodies (anti-thymocyte serum) markedly increased the percentage of regulatory DX5+ and natural killer 1.1+ T cells in the mouse spleen, and prevented acute lethal graft-versus-host disease (GVHD) in BALB/c mice (H-2(d)) following the transplantation of bone marrow (BM) and peripheral blood mononuclear cells (PBMC) from C57BL/6 (H-2(b)) donors. The object of the current study was to determine whether the TLI and anti-thymocyte serum regimen protected natural killer T-cell deficient CD1(-/-) BALB/c mice against GVHD after BM and PBMC transplantation from C57BL/6 donors, and whether a similar conditioning regimen of TLI and anti-thymocyte globulin (ATG) can prevent GVHD in Lewis rat (RT1(l)) hosts after BM and PBMC transplantation from ACI rat (RT1(a)) donors. The experimental results in mice showed that, although wild-type BALB/c hosts are protected in association with a marked increase in CD1- reactive T cells expressing the invariant TCR identified with a CD1 tetramer reagent; CD1(-/-) BALB/c hosts are not. Studies of chimeric donor cells in mice protected from GVHD showed donor T-cell polarization to a Th2 cytokine pattern. Results in rats showed that approximately 1000 fold more donor PBMC cells were required to induce a similar incidence of lethal GVHD in TLI and ATG conditioned hosts as compared with hosts conditioned with single-dose total-body irradiation or total-body irradiation and ATG. Surviving TLI and ATG conditioned rat hosts were complete chimeras. In conclusion, the TLI and ATG/anti-thymocyte serum conditioning regimen protects against GVHD in rats and mice, and regulatory natural killer T cells are required for protection.  相似文献   
59.
The distribution and dynamics of the cytotoxic T lymphocyte (CTL) response to hepatitis B surface antigen (HBsAg) were studied in mice after intramuscular DNA immunization and after hepatic infection by a recombinant adenovirus that expresses the hepatitis B virus genome (Ad-HBV). CTLs specific for HBsAg accumulate preferentially in the spleen after DNA immunization but are primarily intrahepatic after Ad-HBV infection. The secondary CTL response to Ad-HBV in DNA-primed mice is characterized by rapid depletion of effector CTLs from the spleen, and their expansion in the liver where they cause hepatitis, secrete interferon gamma (IFNγ), and inhibit HBV gene expression. Suppression of HBsAg synthesis is accompanied by disappearance of intrahepatic IFNγ-producing CTLs and their reaccumulation in the spleen. The data suggest a possible explanation for the paucity and functional deficiency of HBV-specific CTLs in the periphery during chronic HBV infection, and that the severity of infection can be worsened by a preexisting CTL response if neutralizing antibody is not also present.  相似文献   
60.
Morphological studies on spontaneous systemic amyloidosis were conducted on 222 senescence-accelerated mice (SAM) (P) and on 150 mice in the senescence-resistant series (R).Among the pathologic findings, amyloidosis showed the highest incidence in both SAM (79.7%) and R (32.7%) Although an extensive deposition of amyloid was evident in some aged mice in the R series, a more severe amyloidosis occurred with a higher incidence in the P series. There was a statistical significance between the incidence of amyloidosis and age, in both the P and R series. There were no differences in organ distribution and mode of amyloid deposition between the P and R series or between the sexes. In about 60% of the amyloid-positive cases in the 28 killed SAM and 7 mice in the R series, there were no signs of inflammation or neoplasm.The morphological features in SAM more closely resembled those seen in cases of murine spontaneous senile amyloidosis than the features seen in cases of experimentally induced amyloidosis. This model is expected to be a valuable tool with which to assess the relationship between amyloid deposition and the aging process or senescence, perhaps even cases of human senile amyloidosis.  相似文献   
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