Biomedical subjects

H Ohmori

Publications and source records attributed to H Ohmori.

420 records · Page 24Linked to original sources

PubMedDate not supplied

Scavenging effect of N-acetyl-L-cysteine against reactive oxygen species in human semen: a possible therapeutic modality for male factor infertility?

A new approach to reduce the level of reactive oxygen species (ROS) in human semen by using N-acetyl-L-cysteine (NAC) was evaluated. Semen samples were incubated with or without NAC (1.0 mg ml-1) at room temperature. The chemiluminescent signal of the oxidation of luminol was detected by means of an MTP reader after 0, 20, 40, 60 and 120 min, respectively, using 200 microM luminol. In addition, the dose-dependent action of NAC (0.1, 1.0 and 5.0 mg ml-1) and the influence of NAC on functional sperm parameters (motility and acrosome reaction) were studied. ROS levels decreased significantly after 20 min incubation with NAC. This reduction was greater in the high ROS group (> 30000 counts/10(7) viable sperm at t = 0) than in the low ROS group (< 30000). In addition, a marked dose-dependence of NAC was observed. Concerning sperm function, total sperm motility improved after incubation with NAC, but no significant change was observed with respect to the acrosome reaction. NAC (at concentrations of 1.0 mg ml-1) significantly reduced ROS in human semen and showed the possibility of improving impaired sperm function. After further testing NAC might be useful for the treatment of male infertility patients.

Acetylcysteine↗

PubMedDate not supplied

Differentiation of ejaculates showing reactive oxygen species production by spermatozoa or leukocytes.

Differences between subgroups and correlations between reactive oxygen species (ROS), sperm motility, concentration of leukocytes and viability in semen samples from 143 men were investigated. Patients with azoospermia or leukocytospermia were excluded from the study. Spermatozoa were separated by means of glass wool filtration. Reactive oxygen species were determined by means of luminol chemiluminescence before and after sperm separation; thereafter, normozoospermic and oligozoospermic patients were divided into three subgroups using the mean of all patients investigated (17462 count 10(-7) viable spermatozoa) as cut-off value as follows: G1--high reactive oxygen species production in native semen and after glass wool filtration; G2--high production of reactive oxygen species only in native semen; G3--low levels of reactive oxygen species before and after glass wool filtration. In general, reactive oxygen species were significantly higher in oligozoospermic samples than in normozoospermic samples. In men with normal sperm count, ROS production correlated significantly with the number of leukocytes in the ejaculate before glass wool filtration, but not thereafter. Glass wool filtration is useful to distinguish between sperm samples in which reactive oxygen species are generated by leukocytes and those in which reactive oxygen species are excessively generated by the spermatozoa themselves.

Humans↗

PubMedDate not supplied

Effects of different intensity endurance training on the capillary network in rat skeletal muscle.

Effects of low- and high-intensity endurance training on the capillary luminal diameter and number were studied morphometrically in the rat plantaris muscle. Male Wistar-Imamichi rats were divided into three groups: sedentary control group (Cont, n = 9), low-intensity (running speed of 20 m/min) training group (T-20, n = 8) and high-intensity (running speed of 40 m/min) training group (T-40, n = 7). Rats in both training groups were subjected to each treadmill running program for 60 min/day, 5 days/week for 9 weeks. After 9 weeks of training, citrate synthase activity significantly increased in T-40 compared with Cont, but did not change in T-20. All morphometric parameters with respect to capillary and muscle fiber area were determined in the perfusion-fixed plantaris muscle. The mean muscle fiber areas in both T-20 and T-40 were similar to that in Cont. The capillary-to-fiber ratios were significantly higher in T-20 (2.28 +/- 0.06) and T-40 (2.29 +/- 0.06) than in Cont (2.00 +/- 0.07). The number of capillaries with a small luminal diameter (2-4 microns) was significantly higher in T-20 than in Cont. In contrast, T-40 had a significantly higher number of capillaries with a large luminal diameter (8-10 microns) compared with Cont. This study indicates that endurance training induces changes in the capillary luminal diameter as well as capillary number, and that the adaptive response of the capillary luminal diameter to endurance training depends on the training intensity.

Animals↗

PubMedDate not supplied

Mutational analysis of the CTNNB1 (beta-catenin) gene in human endometrial cancer: frequent mutations at codon 34 that cause nuclear accumulation.

Recently, CTNNB1 (beta-catenin) has been found to function as an oncoprotein that works in the Wnt signaling pathway, and mutation of this gene has been reported in various human cancers. In this study, we analyzed 44 endometrial cancers and found somatic missense mutations in five (11%) tumors. Interestingly, four (80%) of the five tumors with mutations would cause amino acid alterations at residues next to Ser 33, one of the targets for phosphorylation of glycogen synthase kinase (GSK)-3beta. The tumors with mutations showed accumulation of the CTNNB1 protein in cytoplasm and nucleus. This is the first report of frequent somatic mutation of the CTNNB1 gene at codons adjacent to those encoding to Ser/Thr residues in endometrial cancer.

Cell Nucleus↗

PubMedDate not supplied

Anticorresponding mutations of the KRAS and PTEN genes in human endometrial cancer.

PTEN is a newly isolated candidate tumor suppressor gene and its mutation is the most frequently found in endometrial cancer (EC), a very common female pelvic malignant disease. Mutations of the KRAS gene are also reported in this disease. Recent analysis of the PTEN protein suggested the possibility that this protein acts in the same pathway as does the RAS protein. To elucidate this possibility further, we performed a mutation analysis of these two genes in 44 endometrial cancer specimens (38 primary tumors and 6 cell lines). Altogether 23 (52%) of 44 tumors had mutations in either PTEN or KRAS, but none of them had mutations in both of these genes. These results support the idea that the protein products of these two genes act in the same growth regulatory pathway in the endometrium.

Adenocarcinoma↗

PubMedDate not supplied

An improved and simplified method for combined light and scanning electron microscopy in human urinary cytology.

Human bladder-washing and voided urine specimens from normal cases and inflammatory and malignant lesions were examined by the combined use of light microscopy (LM) and scanning electron microscopy (SEM). A newly-designed mesh, which consisted of a piece of gelatin-covered, osmium-impregnated and poly-L-lysine-coated glass slide, 0.85 mm in thickness and containing 42 compartments of 25 sq mm in size, was used in this study. This mesh permitted a direct correlation of LM and SEM images, thus shortening the time of observation of specimens under SEM. With SEM, the diagnosis of malignant exfoliated urothelial cells depended on the presence or absence of pleomorphic microvilli. The technique has enhanced the accuracy of diagnosis over conventional methods, especially for noninvasive, low-grade, papillary tumors of the urinary bladder.

Humans↗