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1.
M. Takada  T. Kono  S. T. Kitai 《Brain research》1992,590(1-2):311-315
Neurotoxic effects of flunarizine (Fz), a selective calcium channel blocker, on the nigrostriatal dopamine system was investigated. Systemic injections of Fz to mice resulted in a transient loss of tyrosine hydroxylase (TH) immunoreactive nigrostriatal neurons without cell loss. TH immunoreactivity in these neurons was greatly reduced as rapidly as one day after drug administration (regardless of dosage used) and thereafter recovered in both dose- and time-dependent manners. Such a novel neurotoxic action of Fz may constitute a morphological substrate for reversible drug-induced parkinsonian signs described in recent clinical case reports.  相似文献   
2.
The effect of various contraceptive methods onChlamydia trachomatis (CT) infection was examined in a group of 158 women, with a mean age of 26.9 years, patients of a family planning clinic. Their symptoms were mild abdominal pain or vaginal discharge. Antibodies to CT were examined by an indirect immunoperoxidase assay, with a commercial kit. From each patient a vaginal smear was collected for bacteriologic and mycologic study.In group I, consisting of 30 married women with a mean age of 31 years, 5 (16.7%) IUD users had a positive test for CT antibodies. In group II, comprising 57 women, with a mean age of 23.3 years, 22 (38.6%) oral contraceptive (OC) users, of whom 94.7% were unmarried, had positive tests for CT antibodies. The difference between these two groups was statistically significant (p<0.05).In group III, comprising 71 women with a mean age of 28.1 years, 62% unmarried and using other contraceptive methods, 15 (21.1%) had a positive test for CT antibodies. The incidence of CT infection was not different in the 3 groups under study, when the factors of age and marital status were taken into consideration (p>0.30). Bacterial vaginal infection was found in 43.3% of the IUD users, compared with only 14% of the OC users (p<0.01).In contrast, in the OC users, candidiasis was predominant, the difference from the other groups being statistically significant (p<0.001). The women with positive antibodies also more frequently had colonies of bacterial and mycological vaginal infection. CT infection is a sexually transmitted disease (STD) related to a specific and non-monogamous sexual life style. The unmarried women in the group of OC users are the most at risk, taking into consideration that they begin sexual life at an early age and that they often change their partners.
Resumen El efecto de varios métodos anticonceptivos en la infección porChlamydia trachomatis (CT), fué examinado en un grupo de 159 pacientes con 26,9 años de edad media, en una clinica de planificación familiar. Sus síntomas fueron: dolor leve abdominal o flujo vaginal. Se examinaron los anticuerpos a CT mediante una prueba comercial de immunoperoxidase indirecta. Se obtuvo un extendido vaginal de eada paciente para un estudio bacteriológico y micológico.En el grupo I, constituido por 30 mujeres casadas con 31 años de edad media, 5 (16,7%) usuarias de DIU tuvieron una prueba de anticuerpos positiva a CT. En el grupo II, constituido por 57 mujeres con 23.3 aflos de edad media, siendo usuarias de anticonceptivos orales (OC) y 94,7% solteras, 22 (38,6%) tuvieron resultados positivos a anticuerpos de CT. La diferencia entre estos dos grupos fue estadísticamente significativa (p<0,05).En el grupo III, constituido por 71 mujeres con 28,1 años de edad media, siendo 62% solteras y usando otros métodos anticonceptivos, 15 (21,1%) tuvieron una prucba de anticuerpos CT positiva. La incidencia de infección de CT no fue diferente en los 3 grupos de estudio cuando se tuvieron en consideracion los factores de edad y estado civil (p>0,30). Se encontró infección bacteriana vaginal en 43,3% de las usuarias de DIU, comparado con 14% de OC (p<0,01).A diferencia, en usuarias de OC predominó la candidiasis, siendo estadísticamente significativa (p<0,001) con otros grupos. Las mujeres con anticuerpos CT positivos, mas frecuentemente tuvieron colonias de infección bacteriana y micológica. La infección CT es una enfermedad transmitida sexualmente (STD), relacionada con un grupo especifico, no monógamo de vida sexual. Las solteras en este grupo de usuarias de OC, son las que tienen el mayor riesgo considerando que empiezan su vida sexual a edad mas temprana y que cambian de pareja con frecuencia.

Resumé L'effet de diverses méthodes contraceptives sur l'infection par laChlamydia trachomatis (CT) a été examiné sur un groupe de 158 femmes dont l'âge moyen était de 26,9 ans qui fréquentaient un clinique de planning familial. Elles présentaient comme symptômes des douleurs abdominales légères et des pertes vaginales. Les anticorps à la CT ont été examinés par un essai indirect à l'immunoperoxydase effectué au moyen d'un matériel commercial. On a procédé à un frottis vaginal sur chaque patiente aux fins d'une étude bactériologique et mycologique.Dans le groupe I, comprenant 30 femmes mariées âgées en moyenne de 31 ans, l'essai sur les anticorps à la CT, chez les 5 utilisatrices de DIU (16,7%), a donné des résultats positifs. Dans le groupe II, comptant 57 femmes d'un âge moyen de 23,3 ans, les utilisatrices de contraceptifs oraux, dont 94,7% étaient célibataires, 22 (38,6%) ont produit des résultate positifs à l'essai sur les anticorps à la CT. La différence entre ces deux groupes était significative du point de vue statistique (p<0.05).Quant au groupe III, composé de 71 femmes âgées en moyenne de 28,1 ans, dont 62% n'étaient pas mariées et faisaient appel à d'autres méthodes contraceptives, les résultats de l'essai sur les anticorps à la CT ont été positifs dans 15 cas. L'lneidence de l'infection par la CT ne différait pas dans les trois groupes étudiés lorsqu'on a tenu compte des facteurs d'âge et de statut matrimonial (p>0.30). L'infection bactérienne vaginale a été retrouvéc chez 43.3% des utilisatrices de DIU, alors qu'elle était de 14% chez les femmes qui prenaient des contraceptifs oraux (p<0.01). Par contre, chez ces dernières, la candidose était prédominante, révélant une différence statistiquement signifieative avae les autres groupes (p<0.001). En outre, les femmes ayant des anticorps positifs à la CT présentaient plus souvent des colonies d'infection vaginale bactériennes et mycologiques. L'infection par la CT est une maladie sexuellement transmissible (MST) liéc à une activité sexuelle spécifique et non monogame. Les femmes célibataires du groupe des utilisatrices de contraceptifs oraux sont les plus exposées à ces risques, compte tenu du fait que leur activité sexuelle commence tôt et qu'elles changent souvent de partenaires.
  相似文献   
3.
1. Intracellular recordings were made from the shell region of the nucleus accumbens in an in vitro slice preparation. The mean resting membrane potential, input resistance, and action potential amplitude of these neurons were -76 +/- 1 mV, 87 +/- 5 M omega and 94 +/- 2 mV (N = 108), respectively. A sample of these neurons (N = 18) was identified as medium spiny neurons with the use of the biocytin-avidin labeling technique. 2. Electrical stimulation of the fornix, subcortical fibers, or neuropil within the nucleus accumbens shell itself elicited a depolarizing postsynaptic potential (PSP). Dopamine (10-100 microM) attenuated PSPs elicited by stimulation of all of these sites. In a paired-pulse stimulation protocol, dopamine was observed to enhance the facilitation of the test response with respect to the conditioning response. 3. The suppressive effect of dopamine was mimicked by the D1 receptor agonist SKF 82958 (10-30 microM), whereas the D2 receptor agonist quinpirole (10-30 microM) was ineffective. The action of dopamine was antagonized by the D1 receptor antagonist Sch 23390 (10-30 microM), but not by the D2 receptor antagonist sulpiride (10-50 microM) or various adrenergic receptor antagonists. 4. The PSP was usually composed of an excitatory postsynaptic potential (EPSP)-inhibitory postsynaptic potential (IPSP) sequence. Dopamine equally attenuated the excitatory and inhibitory component of the synaptic response. The attenuation of both EPSP and IPSP did not depend on membrane potential. 5. Dopamine effects on the resting membrane potential and input resistance were variable and did not correlate with changes in the PSP. Two further indications were found in favor of a presynaptic locus of dopaminergic modulation. First, the time course of the PSP was not altered during dopamine application. Second, dopamine did not attenuate depolarizations induced by bath-applied L-glutamate. In extracellular recordings, it was found that dopamine reduced the population spike but not the presynaptic fiber volley. 6. These findings strongly indicate that dopaminergic modulation of synaptic responses in neurons located in the accumbens shell region is mediated by presynaptic D1 receptors. Notably, dopamine does not exert a purely inhibitory effect on synaptic excitability in the nucleus accumbens, because it suppresses both the excitatory and inhibitory component of the synaptic response.  相似文献   
4.
The authors report a female elderly patient with quadriplegia, hypesthesia below the neck, and rectourinary dysfunction, which were found at autopsy to have been caused by involvement of the lower cervical and upper thoracic segments of the spinal cord in systemic sarcoidosis. Sixty cases of spinal cord sarcoidosis reported in the literature are also reviewed. Most patients had clinical signs which mimicked those of a spinal cord tumor or meningomyelitis. Only in less than one-third of the cases had sarcoidosis been diagnosed before neurological symptoms occurred. Macroscopically, most intramedullary lesions formed a mass, whereas extramedullary lesions usually manifested as meningitis. Histologically, perivascular distribution of sarcoid granulomas was noted in our patient as well as in many cases reported in the literature. The clinical course of the patients with spinal sarcoidosis was usually poor when early diagnosis was not made. ACTA PATHOL. JPN. 35: 1007–1022, 1985.  相似文献   
5.
The morphological organization of the tegmental pedunculopontine nucleus, midbrain extrapyramidal area, substantia nigra and subthalamic nucleus and their interrelationships were studied in rat organotypic culture using immunohistochemistry and NADPH-diaphorase histochemistry. Three coronal sections, one containing the tegmental pedunculopontine nucleus/midbrain extrapyramidal area, another with the substantia nigra and the third with the subthalamic nucleus, were obtained from postnatal 1-2-day-old rats. These sections were co-cultured for 3-4 weeks using the roller-tube technique. In the tegmental pedunculopontine nucleus/midbrain extrapyramidal area, the distribution pattern of cholinergic neurons was similar to that found in the in vivo study. We could, therefore, identify the subdivisions of the tegmental pedunculopontine nucleus (i.e., pars compacta and pars dissipata) and the midbrain extrapyramidal area. As in the in vivo situation, glutamate immunoreactive neurons were also located in these areas. Approximately 10% of NADPH-diaphorase positive neurons in the tegmental pedunculopontine nucleus, were glutamate immunoreactive. In the substantia nigra, as in the in vivo, tyrosine hydroxylase immunoreactive (putative dopaminergic) neurons were identified predominantly in the substantia nigra pars compacta, and parvalbumin immunoreactive neurons (putative GABAergic) mainly in the substantia nigra pars reticulata. The subthalamic nucleus was ladened with glutamate immunoreactive neurons. NADPH-diaphorase stained axons originating from the tegmental pedunculopontine nucleus were traced into the substantia nigra and subthalamic nucleus. They were often in close apposition to tyrosine hydroxylase immunoreactive neurons in the substantia nigra. Parvalbumin immunoreactive fibers from the substantia nigra projected heavily to the midbrain extrapyramidal area, but only sparsely to the tegmental pedunculopontine nucleus and the subthalamic nucleus. These findings indicate that the tegmental pedunculopontine nucleus/midbrain extrapyramidal area, substantia nigra and subthalamic nucleus in the organotypic culture have retained a basic morphological organization and connectivity similar to those seen in the in vivo situation. Therefore, this preparation could be a useful model to conduct further studies to investigate functional circuits among the structures represented.  相似文献   
6.
OBJECTIVE: To compare the microbial contamination rate of infusate in the intravenous tubing of newborns receiving lipid therapy, replacing the intravenous delivery system at 72-hour versus 24-hour intervals. DESIGN: Infants requiring intravenous lipid therapy were randomly assigned to have intravenous sets changed on a 72- or a 24-hour schedule, in a 3:1 ratio, in order to compare the infusate contamination rates in an equivalent number of tubing sets. SETTING: A 35-bed, teaching, referral, neonatal intensive-care unit (NICU). PARTICIPANTS: All neonates admitted to the NICU for whom intravenous lipid was ordered. METHODS: Patients were randomized in pharmacy, on receipt of the order for intravenous lipid therapy, to either 72- or 24-hour administration set changes, and followed until 1 week after discontinuation of lipids or discharge from the NICU. Microbial contamination of the infusate was assessed in both groups at the time of administration set changes. Contamination rates were analyzed separately for the lipid and amino acid-glucose tubing sets. Patient charts were reviewed for clinical and epidemiological data, including birth weight, gestational age, gender, age at start of lipid therapy, duration of parenteral nutrition, and type of intravenous access. RESULTS: During the study period, 1,101 and 1,112 sets were sampled in the 72- and 24-hour groups, respectively. Microbial contamination rates were higher in the 72-hour group than the 24-hour group for lipid infusions (39/1,101 [3.54%] vs 15/1,112 [1.35%]; P=.001) and for amino acid infusions (12/1,093 [1.10%] vs 4/1,103 [0.36%]; P=.076). Logistic regression analysis controlling for birth weight, gestational age, and type of venous access showed that only the tubing change interval was significantly associated with lipid set contaminations (odds ratio, 2.69; P=.0013). The rate of blood cultures ordered was higher in the 72- versus the 24-hour group (6.11 vs 4.99 per 100 patient days of total parenteral nutrition; P=.017), and a higher proportion of infants randomized to the 72-hour group died (8% vs 4%; P=.05), although the excess deaths could not clearly be attributed to bacteremia. CONCLUSION: Microbial contamination of infusion sets is significantly more frequent with 72- than with 24-hour set changes in neonates receiving lipid solutions. This may be associated with an increased mortality rate.  相似文献   
7.
PURPOSE: To investigate whether nitric oxide excreted from cells irradiated with accelerated carbon-ion beams modulates cellular radiosensitivity against irradiation in human glioblastoma A-172 and T98G cells. MATERIALS AND METHODS: Western-blot analysis of inducible nitric oxide synthase, hsp72 and p53, the concentration assay of nitrite in medium and cell survival assay after irradiation with accelerated carbon-ion beams were performed. RESULTS: The accumulation of inducible nitric oxide synthase was caused by accelerated carbon-ion beam irradiation of T98G cells but not of A-172 cells. The accumulation of hsp72 and p53 was observed in A-172 cells after exposure to the conditioned medium of the T98G cells irradiated with accelerated carbon-ion beams, and the accumulation was abolished by the addition of an inhibitor for inducible nitric oxide synthase to the medium. The radiosensitivity of A-172 cells was reduced in the conditioned medium of the T98G cells irradiated with accelerated carbon-ion beams compared with conventional fresh growth medium, and the reduction of radiosensitivity was abolished by the addition of an inducible nitric oxide synthase inhibitor to the conditioned medium. CONCLUSIONS: Nitric oxide excreted from the irradiated donor cells with accelerated carbon-ion beams could modulate the radiosensitivity of recipient cells. These findings indicate the importance of an intercellular signal transduction pathway initiated by nitric oxide in the cellular response to accelerated heavy ions.  相似文献   
8.
9.
Juvenile myelomonocytic leukemia (JMML) is a clonal myeloproliferative/myelodysplastic disorder of early childhood with a poor prognosis. JMML cells are characterized by hypersensitivity to granulocyte-macrophage colony-stimulating factor (GM-CSF) caused by a continuously activated GM-CSF receptor-retrovirus-associated sequence (RAS) signal transduction pathway through various molecular mechanisms, resulting in spontaneous GM colony formation in vitro. Bisphosphonate zoledronic acid (ZOL), a RAS-blocking compound, suppressed colony formation from bone marrow (BM) cells of 8 patients with JMML and 5 healthy control subjects without and with GM-CSF (10 ng/mL), respectively, in a dose-dependent manner in clonal culture. At 10 microM ZOL, however, spontaneous GM colony formation from JMML BM cells decreased to 3%, but the formation of G colonies containing granulocytes, but no macrophages, was enhanced, whereas 40% of GM colonies were retained and G colony formation was not affected in culture of normal BM cells with GM-CSF. In suspension culture, cytochemical and flow cytometric analyses showed that 10 microM ZOL also inhibited spontaneous proliferation and differentiation along monocyte/macrophage lineage of JMML BM cells but not the development of normal BM cells by GM-CSF. The inhibitory effect of ZOL on JMML cells was confirmed at a single-clone level and observed even at 3 microM. The current result offers a novel approach to therapy in JMML.  相似文献   
10.
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