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Biomedical subjects

N Yamaguchi

Publications and source records attributed to N Yamaguchi.

At least 361 records · Page 20Linked to original sources
PubMed1994

Correlations between quantitative EEG and regional cerebral blood flow (SPECT) in patients with partial epilepsy.

During interictal periods in 9 patients with partial epilepsy we examined whether there were correlations between the relative power of background EEG (power spectral analysis) and the absolute values of regional cerebral blood flow (rCBF) measured by 99mTc hexamethylpropylene amine oxime (HMPAO) SPECT in each cerebral region. None of the patients had any organic cerebral lesions on X-ray CT examinations, neurological abnormalities or mental retardation. There was an inverse correlation between rCBF and the relative power of the theta band, and a direct correlation between rCBF and that of the alpha band of 10-12.8 Hz, in the right and/or left frontal, parietal and temporal regions. In the occipital regions, there was a direct correlation only between rCBF and the relative power of the beta band. These correlations were noted whether the analyzed regions were epileptic foci or not. These results suggest that background EEG and rCBF changes in epileptic patients are closely coupled.

Adult↗
PubMed1994

Gender differences in quantitative EEG at rest and during photic stimulation in normal young adults.

In the present study quantitative EEG analysis was performed in 20 male and 20 female healthy adults in order to examine the gender differences in EEG activity at rest and during photic stimulation. The females generally showed a higher amplitude in the resting EEG than the males, with significant differences observed for the delta, theta, alpha 2 and beta bands at the limited electrode sites. The gender differences were more pronounced in EEG activity during photic stimulation, and the females had a higher EEG amplitude in the frequency band identical or harmonically related to the stimulus frequency. These findings provide further evidence that the gender differences exist in EEG activity in both stimulus and nonstimulus conditions.

Adult↗
PubMed1994

A new model for in vivo observation of the feline spinal microcirculation: the closed spinal window.

A new experimental model is described that uniquely allows the in vivo observation and quantification of vascular caliber changes on the dorsal surface of the feline spinal cord. The model consists of a rectangular Plexiglas window that is sutured to the lumbar dura and is supported by a special holder. Inlet and outlet tubes attached to the window serve for topical applications of mock cerebrospinal fluid or vasoactive agents to the surface of the cord and for continuous monitoring of intrathecal pressure. Pial vessels below the window were observed at 200-fold magnification with the aid of a microvideo camera. Spinal arterioles reacted to hypercarbia and superfusion with acetylcholine solution in a manner similar to cerebral arterioles. Tests with increased intrathecal pressure showed that the window remained watertight between 25 and 130 mm Hg, with an average leakage pressure of 57.8 +/- 33.5 mm Hg. To promote the use of this model in other laboratories, the authors give a detailed description of the closed spinal window preparation and report their experiences gained from 50 experiments. It is concluded that the closed spinal window is a highly reproducible model, suitable for the study of the feline spinal microcirculation for several hours in vivo.

Animals↗
PubMed1994

Evaluation of cancer prevention strategies by computerized simulation model: methodological issues.

A computerized simulation model developed to evaluate the potential impact of primary and secondary prevention is discussed from methodologic perspectives. In the simulation model, named CANSAVE (Cancer Strategy Analysis and Validation of Effect), the natural history of cancer was modeled as a Markovian stochastic process from cancer-free state to death. The lung cancer death rate among Japanese males was projected for 50 years to the year 2041. The simulation showed that the age-adjusted death rate would increase and reach a peak of 166 per 100,000 in 1989 and then decrease to 148 in 2003. It then shows a tendency to increase again, up to 255 in 2028. This change may be attributed to a lower smoking initiation rate among those born in the 1930s. Promotion of mass screening programs exhibits a more prompt effect than antismoking efforts, but the reduction in annual deaths is expected to be only 11%, even if a 100% participation is realized by the year 2000. The reduction in smoking initiation rate, on the other hand, begins to show a visible effect very slowly. It was predicted that a 1% annual reduction in smoking initiation rate would result in a 20% decrease in the number of deaths in 2041. The smoking cessation program is in the middle with regard to promptness. The predicted reductions in lung cancer deaths in 2041 were 13, 47, and 66%, respectively, when the annual smoking cessation rate was increased from 0.46% (present status) to 1, 3, and 5%. The combined application of all three preventive measures seems essential to realize the most effective reduction in lung cancer deaths.

Adult↗
PubMed1994

[Efficacy and safety of electroshock therapy without convulsions under general anesthesia in senile depression].

We examined the efficacy and safety of electroshock therapy (EST) under general anesthesia in 26 depressed patients (9 males, 17 females, age range 55-79). The scores of the Hamilton Psychiatric Rating Scale for depression were significantly decreased after EST and clinical symptoms such as depressive mood. psychomotor retardation, anxiety, agitation, suicidal tendencies, hypochondria and sleeplessness improved in all of the patients. Complications included amnesia (16/26), delirium (3/26) and transient arrhythmia (1/26) after EST, but neither lethal nor lasting complications were observed. In summary, EST was an effective and convenient method of treatment for senile depression.

Aged↗
PubMed1994

Publication probability of a study on odds ratio value circumstantial evidence for publication bias in medical study areas.

A summarized odds ratio, calculated from odds ratios of published studies in a meta-analysis, may be overestimated because of publication bias. A method has been developed estimating indirectly the summarized odds ratio of all studies in a given research area, including not only those published but also unpublished. In the present study, a publication probability according to odds ratio value was obtained from the probability density function of all the studies, and a histogram of those published. A publication probability, according to odds ratio value, enables us to infer the quantitative relationship between publication probability and odds ratio. A notable nonpublication of studies whose odds ratios were close to unity was shown from examples of studies on the relationship between passive smoking and lung cancer, whereas nonpublication of studies whose summarized odds ratio was located far from unity was not detected from examples of studies on the relationship between cryptorchidism and testicular cancer. In both study areas, however, the differences between the summarized odds ratios, either with or without the hypothetical unpublished studies, were not large. The small difference, however, should not be ignored, when the study area is recognized as a social problem.

Cryptorchidism↗
PubMed1994

[Thyroid function in patients with anorexia nervosa and depression].

Thyroid hormone levels were measured in 21 patients with anorexia nervosa, 15 patients with depression and 16 patients with severe depression and were compared with those in 53 normal subjects. In anorexia nervosa and severe depressed patients, serum T3, T4, fT3, fT4 and T3/T4 ratio showed significantly lower values than those in normal subjects. However there was no difference between depressed patients and normal subjects. The serum TSH levels were within normal range in all of the studied subjects. Thus, thyroid hormone levels in severe depressed patients were similar to those in anorexia nervosa and the changes were inversely related to disease conditions. The supplementation of thyroid hormones to antidepressant relieved clinical symptoms in some of the severe depressed patients. These results suggested that the changes in thyroid hormone levels in anorexia nervosa and severe depression were mainly due to impaired conversion of T4 to T3 by increased cortisol secretion through emotional stress.

Adult↗
PubMed1994

Prognostic value of immunohistochemical staining for proliferating cell nuclear antigen, p53, and c-erbB-2 in sebaceous gland carcinoma and sweat gland carcinoma: comparison with histopathological parameter.

Thirteen cases of sebaceous gland carcinoma and 10 cases of sweat gland carcinoma were studied using immunohistochemical staining for proliferating cell nuclear antigen (PCNA), c-erbB-2, and p53 to examine correlations among them, and to determine the best predictor of patient prognosis. Many sebaceous gland carcinomas and sweat gland carcinomas showed nuclear accumulation of p53, and patients with tumors showing a PCNA index (percentage of nuclei stained for PCNA) higher than 20%, and a p53 index (percentage of nuclei stained for p53) higher than 10% had short survival. Sebaceous gland carcinomas and sweat gland carcinomas showing c-erbB-2 expression had high PCNA (> 20%) and p53 (> 10%) indices, and were associated with poor prognosis. Histologically, sebaceous gland carcinomas showing a high degree of differentiation and severe nucleolar atypia had high PCNA and p53 indices. A growth pattern of small solid nests and strands, a low degree of differentiation, and the presence of lymphatic permeation in sweat gland carcinoma were often associated with high PCNA and p53 indices. These results suggest that nuclear accumulation of p53 plays an important role in the development of sebaceous gland carcinoma and sweat gland carcinoma. Assessment of PCNA and p53 indices together was very useful for prognostication of patient outcome, using cut-off values of 20% and 10%, respectively, to separate good prognosis from poor. Differentiation of sebaceous gland carcinoma, and c-erbB-2 expression by sweat gland carcinoma were significant independent prognostic indicators.

Adult↗
PubMed1994

[A case of microscopic polyarteritis nodosa accompanied by peripheral neuropathy].

We reported a 64-year-old woman with subacute sensorimotor polyneuropathy accompanied by marked inflammatory reactions and rapidly progressive glomerulonephritis. Polyneuropathy was followed in 3 months by a rapidly progressive renal dysfunction. Sural nerve biopsy revealed marked loss of myelinated fibers and myelin ovoid formation with vasculitis of the small-sized arteries and arterioles. Renal biopsy showed segmental necrotizing glomerulitis. These pathological findings were distinct from those of polyarteritis nodosa and led to a diagnosis of microscopic polyarteritis nodosa (MPN). Oral administration of prednisolone with an additional immunosuppressant was effective not only in alleviating the polyneuropathy, but also in preventing the deterioration of renal function. This is the first report that clearly describes the peripheral neuropathy in MPN.

Aged↗
PubMed1994

Characterization of mouse non-receptor tyrosine kinase gene, HYL.

We previously reported a novel human non-receptor tyrosine kinase gene, HYL (hematopoietic consensus tyrosine-lacking kinase) (Sakano et al., 1994), which consists of each of the SH2 (src homology 2), SH3 and tyrosine kinase catalytic domains. HYL has unique structural features shared with CSK (C-terminal Src kinase). Recently it has also been reported that matk (Bennett et al., 1994) and Ctk (Klages et al., 1994) are isolated as novel kinases with structural similarity to CSK. Comparisons of cDNA sequence indicate the HYL, matk and Ctk are the same gene. We further characterized the mouse HYL genomic structure and HYL mRNA expression in mouse brain. The mouse HYL gene is distributed over 5.8 kb and is composed of 12 exons. The exon-intron organization is almost identical with that of human CSK. The mouse HYL gene was assigned to the R-positive C1 band of chromosome 10 by fluorescent in situ hybridization. RNA in situ hybridization demonstrated the broad distribution of HYL mRNA expression in various neuronal cells. Especially, strong signals were detected in Purkinje cells, pyramidal cells in the hippocampus, granule cells in the dentate gyrus, and mitral cells in the olfactory bulb, indicating that mRNA expression of HYL in brain is very similar to that of SRC-family kinases. These findings establish close relationship between the HYL and CSK genes and also suggest that HYL may play an important role in signal transduction through SRC-family kinases in the central nervous system.

Animals↗
PubMed1994

[Early intervention and treatment of depressive and manic states among university students].

Early intervention and treatment of manic and depressive states at university mental health service are described. Frequency of depression among the population of university students is about 0.1-0.2% and has increased during the last 10 years. The diagnoses of depressive states according to DSM-III-R are as follows; adjustment disorder with depressed mood (50%), major depression (20-30%), dysthymia (20%), and bipolar disorder (5-8%). Some plans for early intervention are discussed, including screening and consultation from the teaching staff and parents. Concerning treatment, it is important to support their academic problems caused by their mental disorders in close cooperation with their parents and their teaching staff.

Adult↗
PubMed1994

[Changes of thyroid hormone levels during ACTH therapy in epileptic children].

To investigate the effect of ACTH on thyroid function, thyroid hormone levels were measured in twelve patients with epileptic children who were treated with ACTH. One week after daily administration of ACTH, serum T3, T4, TSH, thyroglobulin and T3/T4 ratio showed significantly lower values compared with those of pretreatment values (p < 0.001-p < 0.05). Thyroid hormone levels respectively showed negative correlation with cortisol levels before and one week after ACTH treatment respectively. Tapering of ACTH brought a rapid recovery of T3, T4, TSH and thyroglobulin levels with concomitant return of plasma cortisol levels to the normal range. These results suggested that excess ACTH suppressed thyroid hormone secretion mainly through a decreased TSH secretion and a peripheral conversion of T4 to T3 by increased cortisol levels.

Adrenocorticotropic Hormone↗
PubMed1994

Diagnosis of post-transfusion graft-versus-host disease after formalin-fixation.

A 72-year-old woman with multiple recurrence of gallbladder cancer was treated by intrahepatic-arterial infusion of doxorubicin using an extracorporeal system of direct hemoperfusion with venovenous bypass. During this treatment, the patient received 600 ml of fresh whole blood and 30 units of platelet concentrate from five unrelated donors. Thereafter, high fever, skin rash over the whole body, and watery diarrhea developed, followed by leukopenia progressing to a fatal sepsis. Post-transfusion graft-versus-host disease (PT-GVHD) was suspected by the clinical manifestations and postmortem pathologic findings. To establish the diagnosis of PT-GVHD, polymerase chain reaction (PCR) amplification of DNA polymorphism associated with length variation in dinucleotide or trinucleotide microsatellite repeats at the loci of D6S89, int-2 protooncogene, and human growth factor with each of the different primer sets was performed using DNA from blood drawn from the patient with clinically established PT-GVHD of a donor origin and formalin-fixed pancreas of recipient origin. Genetic analysis revealed the changes in the patient's lymphocytes from that of the patient to that of donor origin. The present finding that formalin-fixed tissues can be used as a material of patient origin may contribute to accurate diagnosis of PT-GVHD after autopsy.

Aged↗
PubMed1994

Perioperative blood transfusion promotes recurrence of hepatocellular carcinoma after hepatectomy.

BACKGROUND: Recent advances in liver surgery have reduced operative blood loss drastically, and in more than one half of the patients in our hospital, the liver resection can be accomplished without blood transfusion. METHODS: Two hundred fifty-two patients who underwent complete resection for hepatocellular carcinoma (HCC) were evaluated to assess the effect of perioperative blood transfusion on the recurrence of carcinoma. RESULTS: Carcinoma recurred in 55 (74.3%) of the 74 patients who received a transfusion, but in only 89 (50%) of the 178 patients who did not receive a transfusion (p = 0.0001). This effect was significant even when only a small amount of blood was transfused (p = 0.0001). Based on multivariate analysis, perioperative blood transfusion was a significant predictor for accelerated recurrence (p = 0.003), as were tumor invasiveness (vascular invasion or intrahepatic metastasis) (p = 0.0008) and background liver cirrhosis (p = 0.04). The recurrence-promoting effect of blood transfusion was markedly significant when the patient had either noninvasive HCC (p = 0.0005) or a cirrhotic liver (p < 0.0001). CONCLUSIONS: These results strongly suggest that perioperative blood transfusion substantially promotes the recurrence of HCC after hepatectomy. This effect must be considered and added to the risks of perioperative blood transfusion when formulating a surgical strategy for HCC.

Adult↗
PubMed1994

Synthesis of multilamellar phospholipids in meningioma cells.

This report is to demonstrate that specimen pretreated with tannic acid before osmification permits the ultrastructural identification of multilamellar phospholipids in 23 of the 30 meningiomas. The phospholipids very often had a fingerprint-like appearance, and were found within the cytoplasm of meningioma cells, among the plasma membranes and in the extracellular matrices. A preferential ultrastructural localization of multilamellar phospholipids to the glycogen-rich area within the cytoplasm was seen in 5 cases. They were intermingled with glycogen granules, or the latter were precipitated on the phospholipids. It is suggested that glycogen may serve as a source of energy for precursors of phospholipid synthesis in meningioma cells.

Adult↗
PubMed1993

Intra-hippocampal injection of 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) inhibits partial and generalized seizures induced by kindling stimulation in cats.

This study assessed the effects of microinjections of a serotonin (5-HT) 1A agonist, 8-OH-DPAT, into the feline hippocampus (HIP) on seizure response induced by electrical stimulation of this region. Intra-HIP injection of 8-OH-DPAT (10 nmol) produced a significant elevation in the afterdischarge threshold of partial HIP seizures, with a significant reduction in the duration of focal afterdischarge. Similarly, microinjection of 8-OH-DPAT at the same dose significantly raised the seizure threshold for eliciting generalized seizures in HIP-kindled cats. The present results demonstrate that focally applied 8-OH-DPAT possesses a potent anticonvulsant action, and provide further evidence for the inhibitory role of 5-HT1A receptors in the generation of HIP seizures.

8-Hydroxy-2-(di-n-propylamino)tetralin↗