[Comparison of absorption characteristics of sustained-release theophylline formulations in healthy volunteers].
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Absorption↗
Biomedical subjects
M Takeyama
Publications and source records attributed to M Takeyama.
[Testicular follicle-stimulating hormone receptors in idiopathic male infertility].
To ascertain whether abnormalities in testicular binding of follicle-stimulating hormone (FSH) are related with spermatogenic impairment found in idiopathic male infertility, we measured FSH receptors in testicular tissues obtained by biopsy from 48 infertile men. The 48 infertile men were divided into 3 groups by histological grading using Johnsen's score count, and testicular FSH receptors among these groups were compared. Although 9 of the 18 infertile men with low Johnsen's score count and 5 of the 15 men with middle score count had no obvious FSH binding sites with high affinity, all 15 men with a high score count had high affinity FSH binding sites. In connection with high affinity binding sites for FSH, maximum binding number (Bmax) decreased significantly with the degree of spermatogenic impairment, but the association constant (Ka) was similar among the 3 groups. The present findings demonstrate that the decrease in testicular high affinity binding sites for FSH is related with the degree of spermatogenic impairment found in idiopathic male infertility.
Adult↗
[Influence of temperature on the function of the human testes].
The influence of temperature on human Leydig and Sertoli cell functions was investigated in vitro using the organ culture technique. Specific 125I-FSH and 125I-hCG binding sites in testes from patients with prostate cancer cultured for 1, 3, 5 or 7 days at 33 degrees C or 37 degrees C were measured and compared. There were no significant differences in 125I-FSH or 125I-hCG binding sites between the two temperature groups at 1 to 7 days of culture. Testosterone concentration in the medium obtained from testicular organ culture at 33 degrees C did not differ significantly from that at 37 degrees C at 1 to 7 days of culture. In conclusion, a high temperature may not disturb the Leydig and Sertoli cell functions in a short term.
Aged↗
[Down-regulation of rat and human testicular hCG receptors by hCG].
Changes in rat and human testicular human chorionic gonadotropin (hCG) binding sites induced by hCG were estimated in vivo and in vitro. After a single administration of hCG, the specific hCG binding sites were significantly reduced for 7 and 5 days in rat and human testes, respectively. However, hCG binding sites had recovered to pretreatment values by the 14th day after the administration. Occupied hCG binding sites measured in both rat and human testes accounted for about half of the reduced binding sites on the day after administration of hCG, but thereafter the number of sites occupied was not correlated with the reduction of the binding induced a dose-related significant loss of the specific hCG binding sites for 7 and 5 days in rat and human testes, respectively. Thereafter, the number of binding sites gradually increased. These patterns of change in hCG binding sites in vitro were similar to those in vivo. These findings suggest that the reduction in hCG binding sites in rat and human testes by hCG is due not only to occupancy but also down-regulation of the binding sites. In conclusion, the present testicular organ culture method is useful to study hormonal regulation of testicular function, especially in human testes.
Adult↗
[Temperature influence on testicular function--effect of temperature on DNA synthesis by human testis in-vitro].
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Cells, Cultured↗
[A case of renal angiomyolipoma treated by partial nephrectomy--the management of renal angiomyolipoma from the conservative point of view].
A 25-year-old female was admitted for further investigation of the right renal mass, which was noted during evaluation for hepatitis. She had no personal or family history of stigmas of tuberous sclerosis. On physical examination, a movable hard smooth mass of fist size was palpable in the right abdomen. Drip infusion pyelography revealed an elevation of right kidney. Ultrasonography revealed that the abdominal mass had a high amplitude echo area. On CT the mass was heterogeneous with irregular margin and had regions of low attenuation value, suspicious of a tumor with high fat content. An angiogram of the right renal artery revealed a hypervascular tumor showing multiple saccular aneurysms, and absence of arteriovenous shunting. Based on the aforementioned findings, the mass was diagnosed as renal angiomyolipoma. Partial right nephrectomy was performed through an extraperitoneal approach. Pathological diagnosis was a renal angiomyolipoma. Convalescence was uneventful, and the remaining parenchyma of right kidney was working well on drip infusion pyelography three months after operation. The management of renal angiomyolipoma from the conservative point of view is also discussed.
Adult↗
[Two cases of strangulated urethral prolapse].
This is a report of two cases of strangulated urethral prolapse we recently experienced. One patient, a 70-year-old woman, was admitted to our hospital because of dysuria, painful urination, genital mass (phi 3.0 cm) and bleeding. The other patient, 54 years old, visited our department complaining of pain on urination, and genital mass (phi 2.0 cm) and bleeding. Surgical excision was performed for these prolapsed urethra, and in pathological findings, vascular dilation, blood congestion and partial thromboformation were recognized. Their postoperative course was uneventful without recurrence or abnormal urination. Urethral prolapse is defined as the circular eversion of the urethral mucosa through the external meatus. This condition is a relatively uncommon lesion in the literature, but is a common clinical entity in postmenopausal women and prepubertal girls. Most of the urethral prolapses are small and asymptomatic, but if the prolapsed urethra is large, the mass becomes strangulated, and urinary symptoms, pain and bleeding are present. For the treatment of the urethral prolapse, surgical excision has been widely practiced and is successful.
Aged↗
Beta-subunit of Escherichia coli F1-ATPase. An amino acid replacement within a conserved sequence (G-X-X-X-X-G-K-T/S) of nucleotide-binding proteins.
A mutant strain KF87 of E. coli with a defective beta-subunit (Ala-151----Val) of F1-ATPase was isolated. The mutation is within the conserved sequence (G-X-X-X-X-G-K-T/S) of nucleotide-binding proteins. The mutant F1-ATPase had a much higher rate of uni-site hydrolysis of ATP than the wild type, and about 6% of the wild-type multi-site activity. The mutant enzyme showed defective transmission of conformational change(s) between the ligand- and aurovertin-binding sites.
Adenosine Triphosphate↗
Pathophysiology and prognosis of sudden deafness with special reference to the N1 latency.
Electrocochleography (ECochG) was performed in 84 patients with sudden deafness which were classified into 3 groups according to the ECochG findings, i.e. the unchanged N1 latency, the prolonged N1 latency and the absence of N1 response. The cause of hearing loss in the first group was thought to be strial, postsynaptic or mild cochlear damage and that in the second to be vascular, sensory or neural damage. The first group showed a better prognosis than those of the other two.
Adolescent↗
Effects of hyperprolactinemia on FSH- or LH-induced activities of 17 beta-oxidoreductase, 5 alpha-reductase, and 17-hydroxylase in hypophysectomized rat testes.
Two pituitaries from 7-week-old female rats (Sprague-Dawley strain) were grafted under the capsule of the left kidney of a 49-day old male rat. The pituitary grafted and sham-operated rats were hypophysectomized at 56 days of age. The hypophysectomized rats were given daily injections of NIAMDD-oFSH-13 (20 micrograms/0.5 ml saline), NIAMDD-oLH-23 (9 micrograms/0.5 ml saline) or saline for 4 days starting from day 58. The treated rats and normal male rats were killed at 61 days of age. Testicular homogenates were incubated with [14C]4-androstene-3, 17-dione or [3H] progesterone, and enzyme activities per testes were estimated. Hypophysectomy caused significant decreases in activities of testicular 17 beta-oxidoreductase and 17-hydroxylase. The decreased activity of 17 beta-oxidoreductase was significantly stimulated by FSH or LH treatment, whereas the decreased 17-hydroxylase activity was stimulated only by LH treatment. Although pituitary grafts alone showed little or no effect on these enzyme activities in the hypophysectomized rats, the grafts significantly inhibited FSH-stimulated 17 beta-oxidoreductase activity and the LH-stimulated 17 beta-oxidoreductase and 17-hydroxylase activities but enhanced LH-induced 5 alpha-reductase activity. The present results confirm previous findings that an excess of prolactin directly inhibits LH-stimulated 17-hydroxylase activity but enhances LH-induced 5 alpha-reductase activity in the rat testis. The present results also demonstrate that the same grafts directly inhibit FSH-stimulated 17 beta-oxidoreductase activity but have no effect on FSH-induced 5 alpha-reductase activity.
3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗
Temperature sensitivity of human spermatogonia and spermatocytes in vitro.
To study the effect of temperature on human spermatogenesis, both the number and DNA synthesis of germ cells were investigated in tissue fragments of human testes cultured for 22 h at 31 degrees C and 37 degrees C. The number of differentiated germ cells such as spermatids and spermatozoa cultured at 37 degrees C was significantly smaller than that cultured at 31 degrees C. The number of spermatogonia and resting primary spermatocytes was not significantly different between these two temperatures, but the functional ability of DNA synthesis in these cells was significantly lower at 37 degrees C than at 31 degrees C. It seems that in normal body temperature (37 degrees C) differentiated germ cells such as spermatids and spermatozoa are fragile and the DNA synthesis of spermatogonia and resting primary spermatocytes is retarded.
Culture Techniques↗
[Magnetic resonance imaging in otorhinolaryngology--with special reference to the influence of factors upon NMR parameters and differential diagnosis of otorhinolaryngologic lesions].
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Diagnosis, Differential↗
[Studies on the growth rate of acoustic tumor].
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Adult↗
[Cavernous hemangioma of urinary bladder associated with angiokeratoma of the left leg].
A 45-year-old male was admitted to our hospital with a complaint of asymptomatic macroscopic hematuria. At cystoscopy a multi-lobulated, dark red tumor, the size of a rice grain, was found on the right lateral wall. He also had a 5 X 4 mm purplish skin tumor on the left leg. Double contrast cystogram also showed the shape of the tumor on the right lateral wall of bladder. Based on the aforementioned findings, we diagnosed this case as hemangioma of the urinary bladder associated with the same lesion on the left leg. The bladder tumor was resected transurethrally and the skin lesion was also excised. Pathological diagnoses were cavernous hemangioma of bladder and angiokeratoma of skin, respectively. Including our case we found 62 cases of hemangioma of the urinary bladder in the Japanese literature. Only 5 of them were associated with the hemangiomas of other regions of the body.
Angiokeratoma↗
Escherichia coli H+-ATPase: loss of the carboxyl terminal region of the gamma subunit causes defective assembly of the F1 portion.
Mutant genes for the gamma subunit of H+-translocating ATPase (H+-ATPase) were cloned from eight different strains of Escherichia coli isolated in this laboratory. Determination of their nucleotide sequences revealed that they are amber nonsense mutations: a Gln codon at position 15, 158, 227, 262, and 270, respectively, was replaced by a termination codon in these strains. As terminal Met is missing in the gamma subunit, these results indicate that these strains are capable of synthesizing fragments of gamma subunits of 13, 156, 225, 260, and 268 amino acid residues, respectively. Studies on the properties of membranes of these strains suggested the importance of the region between Gln 269 and the carboxyl terminus (residue 286) for forming a stable F1 complex with ATPase activity and the region between Gln 226 and Gln 261 for normal interaction of F1 with F0. The sequence from Gln 261 to Gln 269 also seemed to be important for stability of F1 assembly on the membranes. The high frequency of the nonsense mutations suggested that the number of essential residues is limited in this subunit. Comparison of the homologies of the amino acid sequences of the gamma subunits from four different sources confirmed this notion: 19% of amino acid residues are identically conserved in these four strains, and the conserved regions are the amino terminal and carboxyl terminal regions.
Adenosine Triphosphate↗
High activity of 17 alpha-oxidoreductase in neonatally grafted mouse testes in adult female mice.
Male and female (WB-C57BL/6)F1 hybrid mice were used. Two testes from neonatal mice were grafted into the spleen of adult male and female mice, and the grafted testes were removed 30 and 60 days after grafting. Normal testes from 30- and 60-day old mice were also used. Testicular homogenates were incubated with [14C]4-androstene-3,17-dione or [3H]progesterone, and enzyme activities per g wet tissue and progesterone metabolism were examined. Activity of 17 alpha-oxidoreductase in the grafted testes in females (20 nmol/g/h) was approx. 10 times the activity in the grafted testes in males or in the normal testes, whereas 17 beta-oxidoreductase activity in the grafted testes in females was the lowest among these testes. The bilateral ovariectomy performed 1 month before the grafting of neonatal testes, artificial cryptorchidism performed at 20 days of age, and estrogen treatment for 10 days by diethylstilbestrol pellets resulted in no significant changes in 17 alpha-oxidoreductase activities in 30- and 60-day old grafted, cryptorchid or normal testes. The major 17-hydroxy-C19-steroids formed in vitro from progesterone by the grafted testes in female mice were testosterone and 17 alpha-hydroxy-4-androsten-3-one (epitestosterone), but the formation of epitestosterone was insignificant in the normal testes. The present results demonstrate for the first time that epitestosterone is formed as one of major C19-steroids in neonatally grafted mouse testes in females but not in those in males or in normal mouse testes. However, the mechanisms remain unexplained.
17-Hydroxysteroid Dehydrogenases↗
Effects of chronic administration of LH releasing hormone on age-dependent activities of testicular 4-ene-5 alpha-reductase and 17 beta-ol-dehydrogenase in mice.
Male (WB X C57BL/6)F1 hybrid mice of 16, 26 and 66 days of age, 4 in each group, were injected daily with 0.2 micrograms/10 g body weight of LH releasing hormone (LHRH) or saline for 14 days. Testicular homogenates were incubated with [14C]4-androstene-3,17-dione and enzyme activities were examined. In mice treated with saline, testicular 17 beta-ol-dehydrogenase activity increased with age but 4-ene-5 alpha-reductase (5 alpha-reductase) activity decreased with age. LHRH treatment for 14 days starting from day 26 resulted in a delay in sexual maturation, as evidence by significant decreases (P less than 0.05) in seminal vesicle weight and testicular 17 beta-ol-dehydrogenase activity and by a significant increase (P less than 0.05) in 5 alpha-reductase activity. However, LHRH treatment starting from day 66 had no significant effect on these testicular enzyme activities.
17-Hydroxysteroid Dehydrogenases↗
Hyperprolactinemia enhances LH-stimulated 4-ene-5 alpha-reductase activity but inhibits LH-induced 17-hydroxylase activity in testes of hypophysectomized immature rats.
Two pituitaries from 7-week old female rats (Sprague-Dawley strain) were grafted under the capsule of the left kidney of 21-day old male rat. The pituitary grafted and sham-operated rats were hypophysectomized at 27 days of age. The hypophysectomized rats, in groups of 4, were given daily injections of 9 micrograms NIAMDD-oLH-23 (minimum effective dose) or saline for 3 days starting from day 29. Testicular homogenates were incubated with [3H]progesterone or [14C]4-androstene-3,17-dione, and enzyme activities per testes were estimated. Testicular HCG-binding sites were also measured. Hypophysectomy caused significant decreases in activities of testicular 5 alpha-reductase, 17-hydroxylase, and 17 beta-hydroxysteroid oxidoreductase. These decreased enzyme activities were significantly stimulated by LH treatment. Although pituitary grafts alone showed no effects on these enzyme activities in the testes of the hypophysectomized rats, the grafts significantly enhanced LH-stimulated 5 alpha-reductase activities but inhibited LH-stimulated 17-hydroxylase activity. Testicular LH/HCG receptors were significantly increased by the grafts, especially in the presence of LH, without affecting affinity for HCG. The present results demonstrate for the first time that hyperprolactinemia directly stimulates LH-stimulated 5 alpha-reductase activity in rat testes. The results also show that the same grafts directly inhibit LH-stimulated 17-hydroxylase activity, probably via postreceptor mechanisms.
17-Hydroxysteroid Dehydrogenases↗