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The in vitro proliferation of peripheral blood lymphocytes (PBLs) without any mitogenic stimulation is one of the hallmarks of human T lymphotropic virus type I (HTLV-I) infection. Recent evidence suggests a difference in the degree of the phenomenon between HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and asymptomatic HTLV-I carriers (AC). In this article, we demonstrated several alterations in the features of the in vitro transformed lymphocytes between patients with HAM/TSP (n = 16) and AC (n = 8). The percentages of total CD8+ and CD8+CD28+ cells were significantly increased in the in vitro proliferating T lymphocytes derived from the patients with HAM/TSP when compared to those from AC. HAM/TSP was segregated from AC by the high degree of the proliferation of CD8+CD28+ cells. The expression of HTLV-I-specific antigens on the cultured PBLs was detected only in the subjects which showed low CD8+CD28+/CD4+ ratio of the in vitro proliferating lymphocytes. These findings suggest that this phenomenon distinguishes HAM/TSP from AC, not only in quantity but also in quality.  相似文献   
3.
The placental transport mechanism of glutathione (GSH) was investigated using microvillous membrane vesicles prepared from human term placenta. Using (3H-glycine)-labeled-GSH, it was clarified that GSH in the extravesicular compartment of placental microvillous membranes was rapidly degraded by gamma-GTP (gamma-glutamyltranspeptidase) and resulting amino acid, and 3H-labeled-glycine was actively transported via a sodium cotransport system. AT-125 treated microvillous membrane vesicles almost entirely lost its gamma-GTP activity, and showed intact GSH transport. Using AT-125 treated microvillous membrane vesicles, it was revealed that GSH was transported across the microvillous membrane as an anion via a membrane potential-dependent mechanism. These results indicated that gamma-GTP which existed in microvillous membrane played a role in GSH metabolism and that intracellular GSH was translocated out of the syncythiotrophoblast cell into the maternal blood space via a specific carrier in microvillous membrane because the GSH concentration was higher in intracellular than extracellular and extracellular membrane potential was positively charged.  相似文献   
4.
Maternal orbital hematoma associated with labor   总被引:1,自引:0,他引:1  
We examined two women with orbital hematomas that occurred during labor. Both women developed sudden diplopia, proptosis, and orbital pain. The location of the hematoma was confirmed by orbital echography and computed tomography. The patients were observed without surgical intervention. Neither patient developed clinical or echographic signs of compressive optic neuropathy. Clinical resolution occurred during the following two weeks. Serial standardized orbital echographic examinations documented resolution of the hematomas.  相似文献   
5.
To elucidate the role of glutathione (GSH) on placental amino acid transport, we investigated L-lysine transport using microvillous membrane vesicles prepared from full term human placenta. 1. The transport of L-lysine into microvillous membrane vesicles was not affected by glutathione. 2. The transport of L-lysine into microvillous membrane vesicles was inhibited by inorganic mercury (Hg2+), and 0.1mM Hg2+ inhibited 34% of this transport and 1mM Hg2+ inhibited 50%. 3. The transport of L-lysine inhibited by Hg2+ was almost completely restored when glutathione was added simultaneously. These results indicated that glutathione defended the inhibitory action of inorganic mercury on L-lysine transport across microvillous membrane.  相似文献   
6.
Summary In a cross-sectional study on 236 individuals in Japan (174 males, 62 females; 149 smokers, 87 non-smokers) plasma nicotine (pnic), cotinine (pcot) and thiocyanate (pSCN), urinary creatinine ratios of nicotine (unic), cotinine (ucot) and thiocyanate (uSCN) as well as carboxyhemoglobin (COHb) and expired carbon monoxide (COex) were determined. All tobacco smoke uptake parameters (TSUP) were significantly elevated in smokers as compared to non-smokers. The discriminant power (smokers vs non-smokers) rank in the following order: ucot pcot unic > pSCN COHb pnic > COex uSCN. All parameters except for pnic are significantly correlated with the self-reported number of cigarettes smoked per day. The reason for the poor correlation of pnic with daily cigarette consumption is the short half-life of pnic coupled with the arbitrary time of blood drawing in relation to the last time of smoking.Dr. Muranaka, the chief author of this paper, was the director of our hospital. He died suddenly on 18 April 1986. This article is therefore the last monument to be planned and achieved under the late Dr. Muranaka's direction.  相似文献   
7.
Incidence of cervical cancer is high among Bolivian Andean women. Human papillomavirus (HPV) infection is known as the major risk factor of cervical cancer. The host immune system plays an important role in the outcome of HPV infection and associated malignancies. In order to study the immunogenetic background of Bolivian Andean women with regard to HPV infection status, we compared HLA class I and class II allele frequencies between 37 HPV positive and 68 HPV negative Bolivian women. Demographic variables, including distribution of Andean ethnicities, were similar in both groups. Comparison of HLA class I allele frequencies between both groups indicated no significant difference. In contrast, HLA class II DRB1*1602 allele, an Amerindian allele, was significantly higher in the HPV positive women compared with HPV negative controls (chi(2) = 5.2, p < 0.05, odds ratio = 3.17; 95% confidence interval = 1.4-8.8). HPV types present in the HPV positive group were HPV-18, -16, -31, -33, and -58. These results suggest that HLA class II DRB1*1602 may confer susceptibility to infection with genetically related HPV types. This is the first report of an HLA class II association with HPV infection in an Andean population.  相似文献   
8.
Human visual evoked potentials were recorded during presentation of photos of human and animal faces and various face features. Negative waves with approximate peak latencies of 165 msec (N170) were bilaterally recorded from the occipito-temporal regions. Mean peak latencies of the N170 were shorter for faces than eyes only. Analyses of amplitudes of evoked potentials indicated that the N170 elicited by faces reflected activity of a specific neural system which was insensitive to detailed differences among individual faces regardless of species, and consequently suggest that this system might function to detect existence of faces in general. On the other hand, the mean amplitude of the N170 elicited by human eyes was significantly larger than those by animal eyes. These differences in response latencies and amplitudes of the N170 suggest existence of at least 2 different visual evoked potentials with similar latencies (i.e., N170) which are sensitive to faces in general and human eyes, respectively. Dipole source localization analysis indicated that dipoles for the N170 elicited by eyes were located in the posterior inferior temporal gyrus, and those for faces, located initially in the same region, but moved toward the fusiform and lingual gyri at the late phase of the N170. The results indicated that information processing of faces and eyes separated at least as early as the latency of the N170 at the posterior inferior temporal gyrus as well as the fusiform and lingual gyri, and might provide neurophysiological and anatomical bases to an initial structural encoding stage of human faces.  相似文献   
9.
A new endemic focus of human T-lymphotropic virus type I (HTL V-I) was recently reported among Mashhadi Jews, a group of immigrants from northeastern Iran to Israel. We extracted DNAs from fresh peripheral blood mononuclear cells (PBMCs) and/or gargle mouthwash from 10 HTL V-I carriers, who consisted of members of one family, and HTL V-I-associated myelopathy (HAM) and adult T-cell leukemia (ATL) patients. Long terminal repeat (LTR) regions of proviral DNAs were sequenced and analyzed phylogenetically. In a phylogenetic tree, all the Mashhadi HTL V-I isolates belonged to subtype A, one of the three subtypes of the cosmopolitan type of HTL V-I, and made a tight cluster distinct from the other isolates of subtype A from Japan, India, the Caribbean Basin, and South America. Although a few nucleotide substitutions were observed among the clones sequenced, no characteristic sequence variation was found in different disease manifestations, even in one family or different sources of DNA preparation.  相似文献   
10.
Recent progress in antiretroviral treatment has led to dramatic improvements in HIV-related morbidity and mortality. These improvements have been fostered by advances in our understanding of HIV-related pathogenesis, the use of plasma HIV RNA levels to monitor patients, and the availability of 13 licensed antiretroviral drugs. Numerous drug combinations, especially those containing three or more agents, can suppress plasma HIV RNA levels below the lower limit of detection in the majority of treated patients. Urologists should be familiar with the limitations of this therapeutic response: patient adherence, drug resistance, a residual burden of chronically infected cells which are refractory to treatment, an unknown impact on HIV in genital secretions, and potential transmissibility through sexual contact.  相似文献   
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