Biomedical subjects

M Fujisawa

Publications and source records attributed to M Fujisawa.

313 records · Page 18Linked to original sources

PubMedDate not supplied

Sertoli cells inhibited apoptosis of pachytene spermatocytes and round spermatids.

Apoptosis in the testis represents an important physiological mechanism that regulates the number of germ cells in the seminiferous epithelium. This apoptosis is believed to be regulated by many factors, including growth factors and cytokines, which appear to suppress apoptosis of the germ cells. In this study, we examined the roles of Sertoli cells on the regulation of pachytene spermatocyte (PS) and round spermatid (RSd) apoptosis with either a co-culture trans-well system or a direct contact system. Apoptosis was detected by low molecular weight DNA fragmentation assay, in situ end labeling, and an LDH assay. In addition, the level of Bcl-2, Bax, and ICE mRNAs in PS and RSd by Northern blot analysis. When PS and RSd were cultured with Sertoli cells in either a trans-well system or direct contact system, the extent of apoptotic DNA fragmentation and LDH level were both significantly lower than those control values. TUNEL staining also revealed the inhibition of apoptosis of PS and RSd when they were cultured with Sertoli cells compared with controls (p <0.05). Moreover, the extent of apoptotic DNA fragmentation and LDH level were significantly lower in the direct contact system than in the trans-well system. TUNEL staining also demonstrated a more decrease in apoptosis of PS and RSd in the direct contact system compared with the trans-well system (p < 0.05). PS and RSd cultured with Sertoli cells exhibited an increase in Bcl-2 mRNA, whereas those cultured with serum-free medium did not show any change. The levels of Bax and ICE mRNAs decreased in PS and RSd cultured with Sertoli cells in comparison with control values. These results suggest that Sertoli cells can prevent apoptosis of germ cells, and that the effect of Sertoli cells on germ cells is mediated by cell to cell interaction or, remote effects of inhibitory factors on apoptosis.

Animals↗

PubMedDate not supplied

Determination of glufosinate ammonium and its metabolite, 3-methylphosphinicopropionic acid, in human serum by gas chromatography-mass spectrometry following mixed-mode solid-phase extraction and t-BDMS derivatization.

A method for the analysis of glufosinate ammonium (GLUF) and its metabolite 3-methylphosphinicopropionic acid (MPPA) in human serum by gas chromatography-mass spectrometry (GC-MS) was developed. Employing a mixed-mode cartridge with both anion exchange action and weak nonpolar interaction, we extracted GLUF and MPPA from the serum and carried out GC-MS analysis of their tert-butyldimethylsilyl derivatives. The detection limits of GLUF and MPPA were 10 pg and 1 pg, respectively. Full mass spectra of 100 pg GLUF and of 10 pg MPPA were easily obtainable. The recovery rate of 90.0+/-11.9% (or better) when the serum concentrations of GLUF and MPPA were 10-0.1 microg/mL. Results of 23 serum samples, from patients with GLUF poisoning, measured by this method correlate well with those derived from the conventional high-performance liquid chromatography method (r = 0.996). The developed GC-MS method is likely to become a useful analytical technique in clinical settings.

Aminobutyrates↗

PubMedDate not supplied

Hyperprolactinaemia among infertile patients and its effect on sperm functions.

The effects of hyperprolactinaemia on sperm function were investigated in 264 men with oligozoo-, asthenozoo-, or teratozoospermia and who were attending a male infertility clinic. None of the patients exhibited galactorrhea or complained of impotence. There was no correlation between abnormal values in spermiogram and hyperprolactinaemia. After multiple measurements of serum prolactin concentration, 15 cases (5.7%) were diagnosed as hyperprolactinaemic (> or = 10 ng ml-1). Six of these patients were taking cimetidine and six were taking anti-anxiety drugs. Serum prolactin returned to the normal level after discontinuation of these drugs; thus these 12 cases were considered as drug-induced hyperprolactinaemia. The other three patients were diagnosed as having pituitary microadenomas and received bromocriptine treatment; the serum prolactin levels normalized within 1 month. No changes in sperm concentration, motility or morphology were found after normalization of serum prolactin levels. Sperm fertilizing ability was monitored by the hamster test for 10 months in the three patients with pituitary microadenoma, and no improvement was observed. Results suggest that hyperprolactinaemia, which does not cause symptoms, has little effect on the impairment of sperm functions. Measurement of serum prolactin in infertile men could be justified, however, for early detection of pituitary adenomas.

Adenoma↗

PubMedDate not supplied

Relationship of acrosin activity to sperm function tests.

Acrosin activity of spermatozoa from infertile patients and fertile volunteers was measured. Acrosin activity of spermatozoa from asthenozoospermic patients and patients with unexplained infertility was lower than that from fertile volunteers. We utilize the zona-free hamster egg-sperm penetration test to select candidates for conventional in vitro fertilization among unexplained infertile patients. The zona-free hamster egg sperm penetration test, however, requires several hours and special equipment which are not used in the clinical setting. It is preferable that other sperm function tests or a combination of them can replace this test. Thus three distinct tests of sperm function, namely, acrosin activity, Penetrak test, hypo-osmotic swelling test, were compared with the hamster test, using spermatozoa from patients with unexplained infertility. A combination of the Penetrak test and measurement of acrosin activity could predict the results of the zona-free hamster egg sperm penetration test with 88.2% accuracy. Thus, the hamster test should be done when either Penetrak test or measurement of acrosin activity showed abnormal values.

Acrosin↗

PubMedDate not supplied

Troglitazone combination therapy in obese type 2 diabetic patients poorly controlled with alpha-glucosidase inhibitors.

The efficacy and safety of treatment with troglitazone combined with an alpha-glucosidase inhibitor, in obese type 2 diabetic patients who were previously administered alpha-glucosidase inhibitors alone, in improving glycaemic control and reducing insulin resistance were studied. Obese type 2 diabetic patients, poorly controlled with alpha-glucosidase inhibitors, were randomized to receive either oral troglitazone 200 mg twice daily (22 patients: group A) or a placebo (20 patients: group B) in addition to their usual alpha-glucosidase inhibitor. In group A, significant decreases in the mean levels of haemoglobin A1c and basal plasma insulin levels were observed 6 months after the start of combined therapy. Serum triglyceride levels significantly decreased but serum lactic acid dehydrogenase and body weight significantly increased. New systemic oedema was observed in six patients. Combined therapy with troglitazone and alpha-glucosidase inhibitors may be effective for diabetic metabolic abnormalities, although the potential development of adverse effects such as body-weight gain and systemic oedema demands vigilance.

Acarbose↗

PubMedDate not supplied

Human trophoblastic cells metabolize 25-hydroxyvitamin D3 in vitro.

Human trophoblastic cells (T3M-3) metabolized 25-hydroxyvitamin D3 into two more polar metabolites during in vitro incubations. A two-step high pressure liquid chromatography system revealed two unique elution positions of those trophoblastic cell-derived metabolites that exactly co-migrated with the elution positions of 5(Z)-19-nor-10-oxo-25-hydroxyvitamin D3 and 5(E)-19-nor-10-oxo-25-hydroxyvitamin D3, respectively. These unique metabolites did not bind specifically to a protein receptor for 1,25-dihydroxyvitamin D3.

Calcifediol↗

PubMedDate not supplied

Levels of interferon alpha and gamma in seminal plasma of normozoospermic, oligozoospermic,and azoospermic men.

The functions of the interferons in the testis are unclear. We investigated the role of interferon alpha and gamma in the seminal plasma on spermatogenesis. The levels of interferon alpha and gamma were determined in the seminal plasma of 101 males including normozoospermic (n = 31), oligozoospermic (n = 57) and azoospermic men (n = 13). The correlation between such levels and clinical parameter (seminogram and serum hormone levels) was evaluated. The seminal plasma level of interferon alpha (92.0 + 110.3 ng/mL) in the normozoospermic men was significantly lower than that of oligozoospermic men (162.4 +/- 130.3 ng/mL) (p < .05). The three groups (normozoospermic, oligozoospermic, and azoospermic group) did not differ as to the level of interferon gamma. No significant correlations were observed between the levels of interferon alpha or gamma in seminal plasma and the serum levels of follicle stimulating hormone (FSH), luteinizing hormone (LH), testosterone, prolactin, or estradiol. Theses results suggest that the level of interferon alpha in the seminal plasma may be related to sperm production.

Humans↗