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1.
Placenta is an important source of leptin during pregnancy that contributes to the high plasma leptin levels in pregnant women. Leptin and its functional receptors are synthesized in trophoblast cells that, in turn, secrete gestational hormones supporting a paracrine or autocrine role for leptin in the endocrine activity of the placenta. In the present study we examined the effect of leptin on in vitro release of gestational hormones (human chorionic gonadotropin (hCG), human placental lactogen (hPL), progesterone, estrogens and testosterone) by human term placental cells in culture. Placentas at term were obtained immediately after delivery from mothers with uncomplicated pregnancies. Progesterone, hCG, hPL, estradiol, estrone, estriol and testosterone levels were measured by different assays in culture media of cells maintained in monolayer culture after incubation for 12, 24, 48 or 72 h with leptin or placebo. Incubation with leptin did not modify hCG, hPL, progesterone, estriol and estrone secretion for any of the doses and times assayed. However, leptin led to a dose-dependent decrease in estradiol release. This effect was observed when treatment with recombinant human leptin spanned from 12 to 72 h. At this time an increase in testosterone levels was observed in leptin-treated cells versus placebo. These results indicate that leptin can be considered a gestational hormone implied in the endocrine function of the placenta, with an important role in control of the production of steroid reproductive hormones in placental cells in vitro.  相似文献   
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Transneuronal degeneration of thalamic neurons following partial deafferentation was studied using [3H]thymidine autoradiography. Timed-pregnant female Sprague-Dawley rats received systemic injections of [3H]thymidine on embryonic day (E) 13, 14 and/or 15. On the day of birth, pups were anesthetized by hypothermia and subjected to unilateral enucleation, unilateral removal of the inferior colliculus or sham lesion. Animals were sacrificed on postnatal day 10 or 30 and the brains processed for autoradiography. Material from sham-lesioned animals demonstrates that neurons destined for the dorsal lateral geniculate nucleus (LGd) undergo final mitoses on E13, 14 and 15. Neurons in the ventral medial geniculate nucleus (MGv) undergo final mitoses on E13 and 14. Thirty days following neonatal unilateral eye removal, the contralateral LGd displays a loss of approximately 30-35% of [3H]thymidine labeled neurons. Neonatal unilateral removal of the inferior colliculus results in a loss of approximately 30-40% of labeled neurons in MGv. For both LGd and MGv, shorter survival times reveal less severe cell loss. Late generated (E15) LGd neurons show less severe loss following enucleation than do earlier generated neurons. These results document the degree of cell loss in sensory thalamic nuclei following deafferentation and demonstrate that [3H]thymidine autoradiography provides a useful quantitative method for assessing anterograde transneuronal cell loss in targeted populations of neurons in the developing central nervous system.  相似文献   
3.
Both oxygen free radicals and excitatory amino acids have been implicated as important cellular toxins in ischemic brain. Recent in vitro studies suggest that there may be a mutual interaction between these two mediators. We explored the relation between oxygen free radicals and excitatory amino acids in the development of ischemic brain edema in vivo. Male Sprague-Dawley rats were treated with the free radical scavenger dimethylthiourea 1 hour before ischemia or with the excitotoxin antagonist MK-801 30 minutes before ischemia produced by occlusion of the middle cerebral artery. Groups of seven or eight animals were treated with vehicle, low-dose (375 mg/kg) dimethylthiourea, high-dose (750 mg/kg) dimethylthiourea, low-dose (0.5 mg/kg) MK-801, high-dose (2.0 mg/kg) MK-801, or both high-dose dimethylthiourea and low-dose MK-801. After 4 hours of ischemia, brain water content was determined. In eight vehicle-treated controls, mean +/- SEM water content of tissue in the center of the ischemic zone was 83.29 +/- 0.18%. A significant reduction of brain edema was observed in all drug-treated groups: for example, 50.2% (p less than 0.001) in the high-dose dimethylthiourea group, 53.7% (p less than 0.001) in the low-dose MK-801 group, and 66.4% (p less than 0.001) in the combined dimethylthiourea and MK-801 group. Combined treatment with dimethylthiourea and MK-801 provided no significant additive effect over that resulting from treatment with MK-801 alone.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
4.
Background/aims: The objective and quantitative assessment of the skin is important in medical and cosmeceutical research. Assessment of color is an important element for analyzing the surface of the skin, which is usually determined subjectively by a doctor or using color analysis devices. These devices, however, cannot provide correct color information because color is construed from the mean value of the observation region, and analysis of color distribution is impossible. The purpose of this paper is to develop an objective analysis method to permit skin color measurement of each pixel unit of an image and analyze the distribution of skin surface color. Methods: The Skin Color Distribution Analyzer (SCDA) is an analysis method newly developed at the Research Institute for Skin Image at Korea University. The SCDA system presented in this paper performed a novel form of quantitative and objective analysis of skin color distribution using each pixel color model parameter found in image wavelength information. In this paper, distribution analysis was conducted on normal skin and skin lesions and skin affected by artificially induced irritant contact dermatitis and pigmented nevous. The method selected a grade using a color model parameter. Twenty healthy Korean males participated in this study. A comparative study of the eight anatomical areas was performed, including the exposure and non‐exposure parts and the medial aspect and the lateral aspect of the forearm. A reliability test for the SCDA system was also conducted with a spectrometer (SPEC) using the color analysis method. Results: Each skin lesion was precisely segmented by grade and each parameter hada different statistical significance for results of analysis of distribution in pigmented nevous and the artificially induced irritant contact dermatitis. Parameters L*, b*, a*, and EI showed salient traits. Showed resemble measured result in the SCDA system and the SPEC of normal skin. The exposed site, in comparison with the non‐exposed site, showed a notable difference in the L* parameter and a significant statistical difference in the x and z parameters, except b*. The comparison of the medial and lateral aspects of the forearm showed a notable difference in the L* parameter and a significant statistical difference in the parameters except y and b*. In the reliability test result using the SCDA system and the SPEC, the SCDA system was highly reliabile in terms of the CV value in all color model parameters. Conclusions: The color distribution analysis method using the SCDA system has revealed an aspect that the existent method of medical research has not shown, and is considered to be more reliable than other methods. This method can provide better study findings because it can be applied to other fields in addition to the medical science field and the ripple effect is thought to be bigger in other science field too.  相似文献   
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The purpose of this study was to determine the genetic characteristics of foot polydactyly and identify its inheritance pattern by analyzing familial pedigree. Five cases from 2 Korean families were studied: 1 is a family whose members have been affected for 4 generations and the other for 2 generations. Using peripheral blood samples, we performed chromosomal analysis using the banding technique with Giemsa stain and karyotyping. We investigated the shape and structure of 46 chromosomes, looking for translation, deletion, inversion, ring chromosome, and isochromosome abnormalities. All peripheral blood samples demonstrated no chromosomal abnormalities, though the genetic nature of foot polydactyly and a new genetic locus was identified recently by other studies. Familial pedigree analysis suggested that polydactyly was inherited as an autosomal dominant trait in the first family. The mode of inheritance for the second family could not be determined due to an insufficient number of family members. The result of this study brought us to the conclusion that, while genetic factors play a major role in polydactyly, other factors may contribute to its occurrence.  相似文献   
7.
AIM: We evaluated differences between men and women with lower urinary tract symptoms (LUTS) combined with nocturia. METHODS: A total of 71 age-matched female-male pairs (median 58, range 20-81 years) who had moderate to severe LUTS and nocturia of more than once per night were enrolled in this study. RESULTS: In the younger group (<50 years), the International Prostate Symptom Score (I-PSS) results of the sexes were not significantly different. However, although total I-PSS results in the elderly group (> or =50 years) were not significantly different, quality of life index scores for women were higher (P = 0.002). On frequency-volume (FV) charts, mean total daytime voided volume (DVV) was significantly higher in younger men than in younger women (P = 0.017), but the mean nocturnal polyuria index (NPi) for women was higher than that for men (P = 0.047). However, maximum DVV (P = 0.009), mean DVV (P < 0.0001), total DVV (P < 0.0001), and mean nocturnal urine volume (P = 0.009) were significantly higher in elderly men than in elderly women. However, numbers of daytime voids were not different. CONCLUSION: Elderly women with LUTS have lower functional bladder capacities than elderly men, as suggested by their smaller mean voided volumes. However, no significant differences were observed between numbers of daytime voids, which was probably due to the smaller total daytime voided volumes of elderly women. In addition, although NPi for younger women and nocturnal urine volume for elderly men was higher, no other differences were observed in terms of other night-time parameters.  相似文献   
8.
A patient with deep venous thrombosis and low protein S activity during the course of Salmonella typhimurium infection is presented. Although protein S deficiency has been reported in patients with disseminated intravascular coagulation, it was not present in this patient and his protein S activity was normal after the findings of infection and deep venous thrombosis disappeared.  相似文献   
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