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Biomedical subjects

S Honma

Publications and source records attributed to S Honma.

At least 163 records · Page 9Linked to original sources
PubMed1992

Roles of paraventricular catecholamines in feeding-associated corticosterone rhythm in rats.

Effects of local destruction of the brain catecholaminergic neurons were examined on the light- and feeding-associated circadian rhythms in plasma corticosterone in rats. 6-Hydroxydopamine (6-OHDA), a selective and long-lasting neurotoxin of the catecholaminergic neurons, was microinjected into the following discrete areas of the brain: the paraventricular nucleus (PVN), median eminence (ME), suprachiasmatic nucleus (SCN), ventromedial hypothalamic nucleus (VMH), lateral hypothalamic nucleus (LH), and the ascending bundle of noradrenergic neurons (NAB). And the feeding-associated as well as the light-associated circadian rhythms in plasma corticosterone were determined. The light-associated circadian rhythm was assayed under a 24-h light-dark cycle with free access to food, whereas the feeding-associated circadian rhythm was measured under restricted daily feeding in which rats had free access to food at a fixed time of day. 6-OHDA reduced the norepinephrine concentrations in respective regions to 10-30% of the control value, except for the LH. The light-associated circadian rhythm was not affected by 6-OHDA into the SCN or PVN. By contrast, 6-OHDA into the PVN or ventral NAB suppressed the feeding-associated circadian peak. 6-OHDA into the VMH and LH showed some effects on plasma corticosterone level but not on the feeding-associated circadian rhythm. 6-OHDA had no systematic effect on plasma corticosterone level when injected into the SCN, ME, and dorsal NAB. These findings indicate that the catecholaminergic neurons projecting to the PVN are involved in the feeding-associated but not in the light-associated circadian rhythms.

Animals↗
PubMed1992

Seasonal variation in the human circadian rhythm: dissociation between sleep and temperature rhythm.

The circadian rhythms of sleep-wakefulness, rectal temperature, and plasma melatonin were measured in 10 healthy male subjects for five consecutive seasons. To minimize direct effects of seasonally changing environmental factors, the subjects stayed in a living facility for 4 days in each season, where ambient temperature, humidity, and social contacts were controlled, while the light intensity of the living room was substantially influenced by natural daylight. Seasonal variations were found in the timing of sleep, the mean body temperature, the phases of circadian temperature and melatonin rhythms, and the phase relation between sleep and the rectal temperature rhythm. The subjects went to bed earliest in summer, intermediate in spring and autumn, and latest in winter. A similar but more pronounced seasonality was observed in the wake-up time, which was earlier in summer than in winter. The acrophases of the rectal temperature and plasma melatonin rhythms, which were calculated by fitting a cosine curve, were located in an earlier time of day in summer than in winter. The phase-angle difference of the rectal temperature rhythm to sleep varied seasonally and was more positive in summer than in winter. These findings indicate that not only the external (to the local time) but also the internal (between circadian rhythms) phase relations of the human circadian rhythms depend on season.

Adult↗
PubMed1992

[Endocrine environment of benign prostatic hyperplasia--relationships of sex steroid hormone levels with age and the size of the prostate].

To determine the influence of endocrine factors on benign prostatic hyperplasia (BHP), the levels of three sex steroid hormones i.e., total testosterone (Total-T), free testosterone (Free-T) and estradiol (E2), were measured in serum of healthy 154 men. Their ages ranged from 18 to 91 years old. In 59 men, prostatic size was estimated by digital examination and was subdivided into three groups: smaller than or equal to walnut size, small hen's egg size and equal to or larger than hen's egg size. Firstly, relationships of sex hormone levels with age were studied. There was a slight decrease in Total-T over 60 years old, a significant decrease in Free-T, and no change in E2 with age. Thus, E2/Total-T and E2/Free-T ratio increased significantly after middle-age. Secondly, relationships of hormone levels with prostatic size were studied. In the larger prostate group, a significantly lower level of Total-T and significantly higher level of E2 were detected. But there was no difference in Free-T. Thus, the prostatic size was correlated positively with E2 level, E2/Total-T and E2/Free-T ratio. These suggest that the endocrine environment tended to be estrogens-dominant with age, in particular, after middle-age, and that patients with large prostates have more estrogens-dominant environments. We conclude that estrogens are key hormones for the induction and the development of BPH.

Adolescent↗
PubMed1992

[Varicella-zoster virus-associated spinal myoclonus without skin lesions].

A 50-year-old woman was admitted to our hospital because of abnormal involuntary movement of upper abdomen. Three months before admission, she had suffered from left lateral chest pain without skin lesions for one week. The neurological examination on admission revealed myoclonus of upper abdomen, and hyperalgesia and thermohyperesthesia from T4 to T9. There was no weakness, the tendon reflexes were symmetrical and the plantar responses were flexor. The surface EMG disclosed the symmetrical, synchronous contractions of m. rectus abdominis and m. obliques externus abdominis. This spinal myoclonus reduced during sleep. The EEG, CT and MRI showed no abnormalities. Serum varicella-zoster virus (VZV) titers increased significantly on follow-up examinations. Clonazepam, 1.5 mg daily was effective in this patient. The myoclonus spontaneously disappeared without clonazepam in six weeks after onset, and at the same time the sensory disturbance also improved. From the neurological findings and clinical course, we consider this spinal myoclonus was probably elicited by involvement of the inhibitory interneurons of the dorsal horns, due to immune response to latent VZV infection but not to direct neuronal destruction by VZV. Spinal myoclonus should be recognized as the spectrum of neurological disease associated with VZV even in the absence of skin lesions.

Female↗
PubMed1992

[The study of ovarian metastasis in uterine cancer].

The correlation between histological ovarian metastasis and histologic cell type, clinical stage, depth of invasion, lymph node metastasis, and menstrual activity were analyzed in 566 patients who underwent surgery for uterine cancer at the hospital of Niigata University between January, 1971 and May, 1990. Ovarian metastasis was studied in 456 patients with stage Ib or more advanced cervical cancer and 110 patients with stage Ia or more advanced endometrial cancer. The following results were obtained: 1. The incidence of ovarian metastasis of cervical cancer by histologic cell type was 18.6% (8/43) for adenocarcinoma, 6.7% (1/15) for mixed type adenocarcinoma and squamous cell carcinoma, and 0% (0/398) for squamous cell carcinoma. The metastasis rate in patients with endometrial carcinoma was 10.8% (10/93) for adenocarcinoma, but there was no metastasis of 2 squamous cell carcinoma, 13 mixed type of adenocarcinoma and squamous cell carcinoma or 2 undifferentiated carcinoma. 2. The incidence of metastasis of cervical adenocarcinoma by stage was 5.3% (1/19) for stage Ib and 29.2% (7/24) for stage II. The metastasis rate of mixed type of adenocarcinoma and squamous cell carcinoma was 0% (0/6) for stage Ib and 11.1% (1/9) for stage II. The incidence of metastasis of endometrial carcinoma was 2.1% (1/47) for stage Ia, 15.0% (3/20) for stage Ib, 15.0% (6/40) for stage II and 0% (0/3) for stage III. 3. All the patients with ovarian metastases of uterine cervical cancer had invasion to a depth of more than 2/3 of the uterine cervix, while the incidence of ovarian metastasis of endometrial carcinoma was increased with deep invasion of the uterine muscular layer, and metastasis was present even in shallow invasion.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma↗
PubMed1991

Age as a prognostic factor in patients with squamous cell carcinoma of the uterine cervix.

Correlations between age and several prognostic factors, such as histologic cell type, depth of invasion, intravascular invasion, and lymph node metastases (LNM), were analyzed in squamous cell carcinoma of the cervix (SCC). A total of 380 patients with Stage IB or more advanced SCC underwent radical hysterectomy at the authors' institution from 1971 to 1987. The cases were divided into four age groups: 30 to 39 years, 40 to 49 years, 50 to 59 years, and 60 to 69 years. The depth of invasion was classified in four categories according to pathologic examination of surgical specimens. The only significant factor was the frequency of LNM with deeper invasion, which was less in the 60-to-69-year age group than in the younger age groups. The 5-year survival rates of the patients with LNM also were higher in the 60-to-69-year group. Thus, age 60 or older can be considered a prognostic factor correlating to LNM in squamous cell carcinoma of the cervix.

Adult↗
PubMed1991

[Estrogen formation in the central nervous system and characteristics of aromatase of rat hypothalamus].

Estrogen formation from androst-4-ene-3,17-dione and its kinetics were studied using microsomes from rat hypothalamus. [4-14C] androst-4-ene-3,17-dione and a homogenate of rat hypothalamus were incubated in the presence of NADPH at 37 degrees C for 3 hrs. The estrogen fraction was extracted from the incubation mixture with ethyl acetate, purified by column chromatography on Sephadex LH-20 and Bond Elut C18, and separated into estrone and estradiol fractions by HPLC. In analysis of the trimethylsilyl (TMS) derivatives of each fraction by gas chromatography-mass spectrometry (GC-MS), the molecular ion peak of the estrone fraction appeared at m/z 344, within 2 amu of that for the TMS derivative of natural estrone. The retention time of the estrone fraction derivative was 11.6 min, the same as that of natural estrone. 14C-estrone was thus concluded to be biosynthesized from [4-14C]-androst-4-ene-3,17-dione in rat hypothalamus. The kinetics of the aromatase of rat hypothalamic tissue was studied by measuring 3H2O released from [1 beta-3H]-androst-4-ene-3,17-dione and estrone as the estrogen product by measured gas chromatography selected ion monitoring (GC-SIM). High correlation was found between 3H2O release and estrone measured by GC-SIM (r = 0.97). Aromatase activity was linear with respect to incubation time and quantity of tissue. Km and Vmax were 30.3 nM and 7.98 fmol estrogen/h/mg of wet tissue, respectively. 4-hydroxyandrostenedione (4-OH-A) suppressed the activity of aromatase in both rat hypothalamic and human placental tissue in a concentration-dependent manner. Polyclonal IgG to human placental aromatase also suppressed aromatase activity of human placental tissue, but only slightly suppressed that of rat hypothalamus. The molecular structure of aromatase in rat hypothalamus was thus concluded to differ from that in human placenta.

Androstenedione↗
PubMed1991

Collateral circulation in Kawasaki disease with coronary occlusion or severe stenosis.

Forty patients with Kawasaki disease with severe coronary sequelae were investigated. All had at least a 90% reduction in the diameter of the major coronary artery. Collateral vessels were seen in 32 of 33 (97%) patients with total occlusion. All patients with severe stenosis but not total occlusion had no or poorly developed collateral vessels. Analysis according to the presence or absence of collateral vessels showed no significant differences in the results of treadmill stress testing and myocardial imaging between these two groups. In patients treated surgically, the abnormalities recognized by these tests were normalized or improved when the bypass was patent. These data indicate that collateral circulation in patients with Kawasaki disease cannot be seen angiographically unless there is total occlusion and the presence of collateral circulation cannot provide protection against stress-induced myocardial ischemia.

Arterial Occlusive Diseases↗
PubMed1991

Methamphetamine effects on rat circadian clock depend on actograph.

Methamphetamine effects on the rest-activity rhythm were examined in 12 blinded rats using two different actographs, an Animex and a running-wheel. D-Methamphetamine was administered chronically by dissolving it in drinking water. During methamphetamine treatment, the rest-activity rhythm measured by an Animex showed a clear sign of relative coordination in addition to the general enhancement of activity level. Analyses of pre- and posttreatment activity rhythms revealed that neither the phase nor the period was affected by methamphetamine treatment. On the other hand, the circadian period was lengthened by methamphetamine treatment when locomotor activity was measured by a running-wheel. These results confirmed our previous findings that the chronic treatment of methamphetamine modified the expression of the circadian rhythms but did not affect the underlying oscillation when measured by an Animex, and further indicated that methamphetamine could affect the underlying oscillation when rats had free access to a running-wheel. It is concluded that the effects of methamphetamine on the circadian clock depend on actograph.

Animals↗
PubMed1991

[A case of HTLV-1 associated myelopathy and adult T-cell leukemia, presenting unique muscle pathology including rimmed vacuole].

A 63-year-old man developed muscular atrophy and weakness in his four extremities since 1983, and was pointed out to have smoldering ATL by elevated HTLV-1 antibody titers in the serum (x 2,500) and CSF (x 32) in 1985. Neurological examinations revealed proximal muscular weakness and atrophy of four extremities, and mild spasticity of both legs. Deep tendon reflexes were hypoactive in both arms and hyperactive in both lower extremities with ankle clonus and bilateral positive Babinski and Chaddock reflexes. These findings were compatible with HAM. His gait, however, was markedly waddling, requiring support. Muscle biopsy at left biceps muscle revealed inflammatory change with rimmed vacuoles, small group atrophy, and marked type 1 fiber predominance. These findings on muscle biopsy are different from those of previously reported cases with HAM, showing some similarities to inclusion body myositis or distal myopathy with rimmed vacuole.

Biopsy↗
PubMed1991

[Epidemiologic and clinicopathologic studies of partial hydatidiform mole].

To determine the epidemiological and clinicopathological characteristics of partial hydatidiform mole (PHM), a comparative study of PHM and complete hydatidiform mole (CHM) was performed in molar patients who were entered in the regional registry of Niigata Prefecture and/or who were admitted for treatment at Niigata University Hospital. The results obtained are as follows. 1. From 1971 to 1988, 2,290 hydatidiform moles (HMs) were documented in the registry. The incidence of HM was annually decreasing with an almost constant ratio to the total number of pregnancies. Since 1986, the number of PHM was rising with an inverse decrease in CHM. One hundred fifty one of 1,923 CHM (7.9%) had persistent trophoblastic disease (PTD), but on the other hand only 6 of 367 cases PHM (1.6%) had. 2. In 275 patients treated in our hospital from 1971 to 1990, 134 of 240 with CHM (55.8%) and 6 of 35 with PHM (17.1%) experienced PTD. Of 6 PTD patients following PHM, 3 had invasive mole, 1 metastatic mole and 2 post molar persistent hCG, but no choriocarcinoma. 3. The recent study of DNA analysis in molar tissue revealed that one case, which had been diagnosed as PHM, coexisted with CHM and non-molar pregnancy.

Adult↗
PubMed1991

[Effects of various growth factors on the proliferation and the differentiation of trophoblastic cells in vitro].

EGF, PDGF, IL-6, TGF-beta 1 and supernatants from decidual cell cultures were added in various concentrations to cultures of normal trophoblastic cells in vitro. Effects on cell proliferation and differentiation were assessed by using 3H-thymidine uptake test and measuring hPL, hCG production in culture media, respectively. EGF stimulated only hPL, hCG production and in contrast, PDGF stimulated 3H-thymidine uptake only. IL-6, TGF-beta 1 and decidual supernatants stimulated both hPL, hCG production and 3H-thymidine uptake, especially TGF-beta 1 and decidual supernatants. These results suggest that EGF is related to the differentiation, PDGF is to the proliferation, and IL-6, TGF-beta 1 and decidual supernatants are to both the differentiation and proliferation of trophoblastic cells. Further understanding of the effects of these products on trophoblastic growth may provide important insights into mechanisms of early pregnancy development.

Cell Differentiation↗