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31.
Plasmid clones of three independent genomic fragments of the gene for human N -acetylgalactosamine-6-sulfate sulfatase (GALNS; EC 3.1.6.4) were utilized in a fluorescence in situ suppression hybridization study to assign the locus to chromosome 16q24. Enzyme assay for GALNS in a patient with del(16)(q22.1) confirmed this finding.  相似文献   
32.
Thymidine phosphorylase (TP) is known to be more concentrated in human cancer tissues than in adjacent normal tissue based on findings using enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry. However, the ultrastructural localization of TP in cancer tissues has not previously been demonstrated. We investigated the localization of TP in gastric cancer and colorectal cancer tissue by ELISA, immunohistochemistry, and immunoelectron microscopy. Between April 1997 and May 2000, we obtained surgically resected specimens from 42, 46, and 36 cases of advanced gastric, colon, and rectal cancer, respectively. ELISA demonstrated that the TP level was higher in cancer tissues than in adjacent normal tissue. Immunohistochemically, cancer cells were positive for the enzyme in some cases. However, in a number of cases immunopositive inflammatory cells were also present in cancerous tissues. At the electron microscope level, TP was diffusely distributed in the cytoplasm of cancer cells and in the mitochondria of the neutrophil in gastric cancer tissue. In rectal cancer tissues, cytoplasmic granules in macrophages in cancer tissues were immunoreactive for the TP. These findings suggest that TP is produced by macrophages and exists in neutrophils and cancer cells.  相似文献   
33.
The diversity of reproductive strategies found in fish is attributed to the adaptation of gametogenesis to different habitats. To date, however, information about the dynamics of male gametogenesis and its molecular mechanisms of control by the brain-pituitary-gonadal (BPG) axis, a well-known facet of the endocrine system in vertebrates, is not sufficient to explain the variation in spawning and regulatory mechanisms among species. The bambooleaf wrasse (Pseudolabrus sieboldi) is a protogynous hermaphrodite fish that shows clear diurnal fluctuations in gonadotropin gene expression and serum sex steroid levels associated with spawning. In this study, morphometrical and histological analyses were performed to determine the number of spermatogonial generations in the testis of the sex-changed male (secondary testis). In addition, the diurnal dynamics of S-phase entry of germ cells was explored by measuring the frequency of BrdU-incorporating germ cells at different times of day. We found that the bambooleaf wrasse spermatozoa were generated through nine spermatogonial generations, followed by meiotic divisions accompanied by loss of some spermatocytes and spermatids through apoptosis. BrdU analyses revealed a high frequency of entry into S-phase of undifferentiated type A spermatogonia at 03:00?hr. On the other hand, the frequency of spermatocytes at S-phase of the cell cycle decreased during 00:00-09:00?hr. This study demonstrates for the first time the daily fluctuations of S-phase entry of male germ cells in fish. These results will provide a useful foundation for understanding the roles of endocrinological and cytological regulation of fish spermatogenesis.  相似文献   
34.

Background/Aims

Age, proteinuria, metabolic syndrome, and hyperuricemia are the reported risk factors for chronic kidney disease (CKD) and cardiovascular disease (CVD). However, the best predictor of changes in renal function in the early stages of renal disease in a healthy middle-aged population is still unknown. Our study evaluated the correlation between changes in renal function and common risk factors to determine such a predictor.

Methods

In total, 2,853 healthy persons aged ≤50 years participated in the study. They had no proteinuria and were not on medications for hypertension, diabetes mellitus, hyperlipidemia, or hyperuricemia. Over 2 years, participants underwent annual health screening. The relationship between changes in estimated glomerular filtration rate (eGFR) and changes in risk factors for CKD was evaluated using univariate and multivariate linear regression analyses.

Results

Over 2 years, eGFR showed a significant decrease. Univariate regression analysis revealed that changes in fasting plasma glucose (FPG), total cholesterol, LDL-cholesterol, serum uric acid levels, and hemoglobin showed a significant negative correlation with changes in eGFR. Multiple regression analysis confirmed that changes in FPG, serum uric acid levels, in particular, and hemoglobin had a significant negative correlation with changes in eGFR.

Conclusion

The changes in eGFR and other variables over 2 years were small and could be within expected biologic variation. A longer observational study is needed to elucidate whether FPG, serum uric acid and hemoglobin represent the earliest markers of eGFR decline.  相似文献   
35.
ABSTRACT: BACKGROUND: Kisspeptins (Kiss) are prime players in the control of reproductive function through their regulation of gonadotropin-releasing hormone (GnRH) expression in the brain. The experimental scombroid fish, chub mackerel (Scomber japonicus) expresses two kiss (kiss1 and kiss2) and three gnrh (gnrh1, gnrh2, and gnrh3) forms in the brain. In the present study, we analyzed expression changes of kiss and gnrh mRNAs in the brain and corresponding GnRH peptides in the brain and pituitary during final ovarian maturation (FOM) and ovulation. METHODS: Female fish possessing late vitellogenic oocytes were injected with GnRH analogue to induce FOM and ovulation. Fish were observed for daily spawning activities and sampled one week post-injection at germinal vesicle migration (GVM), oocyte hydration, ovulation, and post-ovulatory time periods. Changes in relative mRNA levels of kiss and gnrh forms in the brain were determined using quantitative real-time PCR. Changes in GnRH peptides in the brain and pituitary were analyzed using time-resolved fluoroimmunoassay. RESULTS: Both kiss1 and kiss2 mRNA levels in the brain were low at late vitellogenic stage and increased significantly during the GVM period. However, kiss1 mRNA levels decreased during oocyte hydration before increasing again at ovulatory and post-ovulatory periods. In contrast, kiss2 mRNA levels decreased at ovulatory and post-ovulatory periods. Levels of gnrh1 mRNA in the brain increased only during post-ovulatory period. However, levels of gnrh2 and gnrh3 mRNAs were elevated during GVM and then, decreased during oocyte hydration before increasing again at ovulatory period. During post-ovulatory period, both gnrh2 and gnrh3 mRNA levels declined. Peptide levels of all three GnRH forms in the brain were elevated during GVM and oocyte hydration; their levels were significantly lower during late vitellogenic, ovulatory, and post-ovulatory periods. In contrast, pituitary GnRH peptide levels did not show any significant fluctuations, with the GnRH1 peptide levels being many-fold higher than the GnRH2 and GnRH3 forms. CONCLUSION: The results indicate increased expression of multiple Kiss and GnRH forms in the brain and suggest their possible involvement in the regulation of FOM and ovulation in captive female chub mackerel.  相似文献   
36.
Our previous study showed that relatively low-intensity (approximately 50% one-repetition maximum [1RM]) resistance training (knee extension) with slow movement and tonic force generation (LST) caused as significant an increase in muscular size and strength as high-intensity (approximately 80% 1RM) resistance training with normal speed (HN). However, that study examined only local effects of one type of exercise (knee extension) on knee extensor muscles. The present study was performed to examine whether a whole-body LST resistance training regimen is as effective on muscular hypertrophy and strength gain as HN resistance training. Thirty-six healthy young men without experience of regular resistance training were assigned into three groups (each n = 12) and performed whole-body resistance training regimens comprising five types of exercise (vertical squat, chest press, latissimus dorsi pull-down, abdominal bend, and back extension: three sets each) with LST (approximately 55-60% 1RM, 3 seconds for eccentric and concentric actions, and no relaxing phase); HN (approximately 80-90% 1RM, 1 second for concentric and eccentric actions, 1 second for relaxing); and a sedentary control group (CON). The mean repetition maximum was eight-repetition maximum in LST and HN. The training session was performed twice a week for 13 weeks. The LST training caused significant (p < 0.05) increases in whole-body muscle thickness (6.8 +/- 3.4% in a sum of six sites) and 1RM strength (33.0 +/- 8.8% in a sum of five exercises) comparable with those induced by HN training (9.1 +/- 4.2%, 41.2 +/- 7.6% in each measurement item). There were no such changes in the CON group. The results suggest that a whole-body LST resistance training regimen is as effective for muscular hypertrophy and strength gain as HN resistance training.  相似文献   
37.
To understand the effects of climate change on the growing season of plants in Japan, we conducted trend analysis of phenological phases and examined the relationship between phenology and air temperatures. We used phenological data for Ginkgo biloba L., collected from 1953 to 2000. We defined the beginning and the end of the growing season (BGS and EGS) as the dates of budding and leaf fall, respectively. Changes in the air temperature in the 45 days before the date of BGS affected annual variation in BGS. The annual variation in air temperature over the 85 days before EGS affected the date of EGS. The average annual air temperature in Japan has increased by 1.3°C over the last four decades (1961–2000), and this increase has caused changes in ginkgo phenology. In the last five decades (1953–2000), BGS has occurred approximately 4 days earlier than previously, and EGS has occurred about 8 days later. Consequently, since 1953 the length of the growing season (LGS) has been extended by 12 days. Since around 1970, LGS and air temperatures have shown increasing trends. Although many researchers have stated that phenological events are not affected by the air temperature in the fall, we found high correlations not only between budding dates and air temperatures in spring but also between leaf‐fall dates and air temperatures in autumn. If the mean annual air temperature increases by 1°C, LGS could be extended by 10 days. We also examined the spatial distribution of the rate of LGS extension, but we did not find an obvious relationship between LGS extension and latitude.  相似文献   
38.
Selective growth inhibitors of Sphaerotilus natans were detected in the culture broths of several strains of Streptomyces. Anslimins A and B were isolated from the culture broth of Streptomyces oganonensis by adsorption on resinous adsorbent followed by elution with 50% aqueous acetone. The A and B components were then separated by cellulose powder chromatography. Physicochemical parameters of anslimins A and B revealed that these compounds are new peptide-containing structures. Anslimins A and B inhibited growth of S. natans at 0.78 and 0.39 μg/ml, respectively, but showed no activity against any of the other test microorganisms at 100 to 200 mg/ml. The anslimins had no harmful effect on guppies at a concentration of 100 mg/liter.  相似文献   
39.
The fluorescence spectra and fluorescence lifetimes due to tryptophan residues in HbA, Hb Chesapeake, NES-des-Arg Hb and Hb Kempsey were determined at room temperature. The fluorescence intensity and apparent fluorescence lifetimes decrease when the deoxy or T structure in HbA changes to the oxy or R structure, while no significant difference was observed in Hb Kempsey. The difference of fluorescence behavior was ascribed to the quaternary conformational transition of T- and R-states.  相似文献   
40.
The two different regions of the plasma membrane, i.e. apical and basolateral membranes, of intestinal epithelial cells were analyzed as to their proten components. They showed very contrasting profiles on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The apical membranes possessed several major components with apparent molecular weights larger than 108 000, most of which were also periodic acid-Schiff reagent positive. In contrast, there were no protein components with corresponding molecular weights in the basolateral membrane. The electrophoretic profile of the latter was strinkingly simple. The dominant band was assigned a molecular weight of 101 000 and was periodic acid-Schiff reagent negative. No major components were shared by the two membranes.  相似文献   
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