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Biomedical subjects

Hiroyuki Shimizu

Publications and source records attributed to Hiroyuki Shimizu.

At least 73 records · Page 4Linked to original sources

The prevalence of primary open-angle glaucoma in Japanese: the Tajimi Study.

PURPOSE: To assess the prevalence of primary open-angle glaucoma (POAG) and its association with intraocular pressure (IOP) in Tajimi City in central Japan. DESIGN: A cross-sectional epidemiologic study in a defined population. PARTICIPANTS: Subjects randomly selected from the population older than 40 years in Tajimi City. INTERVENTION: Each subject underwent a screening examination comprised of an interview and ophthalmic examinations, including measurement of IOP by a Goldmann applanation tonometer, central corneal thickness (CCT), slit-lamp examination, fundus photography, and a screening visual field test using frequency doubling technology. When ocular diseases were suspected, the subjects were referred for definitive examination. During the definitive examination, slit-lamp examination, IOP measurement, a visual field test using Humphrey Field Analyzer 30-2 SITA Standard program (Humphrey Instruments, San Leandro, CA), optic disc and fundus examination, and gonioscopy were performed and stereoscopic disc photographs were obtained. A diagnosis of glaucoma was made based on optic disc appearance, perimetric results, and other ocular findings. MAIN OUTCOME MEASURES: Prevalence of POAG, mean IOP, and mean CCT. RESULTS: Of 3870 eligible people, 3021 (78.1%) participated in the study. The estimated prevalence of POAG in the population older than 40 years was 3.9% (95% confidence interval [CI]), 3.2%-4.6%). The prevalence of cases of POAG with IOP levels of 21 mmHg or less was 3.6% (95% CI, 2.9%-4.3%), whereas the prevalence for those with IOP levels of more than 21 mmHg was 0.3% (95% CI, 0.1%-0.5%). The average IOP for eyes with POAG was 15.4+/-2.8 (standard deviation) in the right eye (n = 115) and 15.2+/-2.8 mmHg in the left eye (n = 115), which was significantly higher than that of nonglaucoma subjects (14.5+/-2.5 in the right eye; n = 2759; P = 0.0004; and 14.4+/-2.6 mmHg in the left eye; n = 2757; P = 0.0026). The mean CCT of POAG eyes with IOP levels of 21 mmHg or less was 518+/-29 (n = 109) in the right eye and 519+/-29 microm (n = 110) in the left eye, levels that were not significantly different from that of nonglaucoma eyes (520+/-32 microm [n = 2690]; and 522+/-32 microm [n = 2692]; P>0.05). CONCLUSIONS: The prevalence of POAG in this population was 3.9%. In 92% patients with POAG, the IOP was 21 mmHg or less.

Adult↗

Intracranial metastatic prostate carcinoma presenting as intermittent double vision.

We describe a prostate cancer patient whose initial symptom was intermittent double vision. Intracranial magnetic resonance imaging demonstrated a pituitary mass extending to the cavernous sinus, which caused the double vision. After hormonal therapy for prostate cancer, the pituitary mass disappeared, and double vision was completely resolved without local therapy for the brain. In the 19 months of follow-up after hormone treatment, the prostate cancer remained stable, and the patient remained neurologically intact.

Adenocarcinoma↗

The relationships of a rationality/antiemotionality personality scale to mortalities of cancer and cardiovascular disease in a community population in Japan.

OBJECTIVE: Grossarth-Maticek et al. reported that an individual's level on a rationality/antiemotionality (R/A) personality was strongly predictive of cancer, ischemic heart disease and stroke mortality. To investigate the relationships of an individual's level on the R/A personality to cancer and cardiovascular disease mortality in Japan, we conducted a population-based cohort study. METHOD: A self-administered questionnaire was distributed to 36990 Japanese residents in September 1992. The response rate was 90.3%. Data from 13226 males and 14880 females were analyzed. Dates and causes of death through December 31, 1999 were obtained for deceased participants. RESULTS: The results from multivariate hazard ratios (HRs) revealed that males scoring in the middle level compared to those scoring in the lower level of the R/A personality scale decreased their risk of death from cancer and cardiovascular diseases after controlling for covariates. CONCLUSIONS: The level on the R/A personality scale may affect mortality from cancer and cardiovascular diseases differently in Japan.

Cardiovascular Diseases↗

Health attitudes and behaviors: comparison of Japanese and Americans of Japanese and European Ancestry.

Adults living in Japan (N = 357) and the US (N = 223) completed semi-structured interviews assessing health-related attitudes and practices. The US respondents were of Japanese (N = 106) and European (N = 117) ancestry. Results indicated considerable similarity between the two US groups and significant differences between the Japanese and American respondents. The Japanese respondents placed less priority on health, had less belief in the efficacy of health screening tests, lower levels of internal health locus of control (HLOC), and higher levels of chance and powerful-others HLOC. While Japanese and Americans had similar overall levels of healthy behaviors, the Japanese were less likely to have obtained health screening tests (especially gynecologic exams). The findings have implications for adapting health promotion programs in the context of Japanese and American cultures.

Asian People↗

Molecular epidemiology of enterovirus 71 infection in the Western Pacific Region.

BACKGROUND: Recently, there have been large outbreaks of hand, foot and mouth disease (HFMD) mainly caused by enterovirus 71 (EV71) associated with severe neurological diseases in the Western Pacific Region (WPR). To monitor the realtime trend of EV71 transmission throughout the WPR, the authors conducted a molecular epidemiological analysis of EV71 infection. METHODS: Viruses were isolated from clinical samples from patients with HFMD or those with neurological complications. The EV71 isolates were identified by microneutralization assay. The VP4 and/or VP1 regions of recent EV71 isolates were sequenced and subjected to phylogenetic analysis using reference EV71 strains. RESULTS: The phylogenetic analysis of EV71 isolates from the WPR revealed two major genogroups, B and C, based on the nucleotide sequence alignment of the VP1 or VP4 region. These two major genogroups were further divided into subgenogroups, B1, B2, B3, and B4 and C1, C2, C3 and C4, respectively. CONCLUSIONS: The molecular epidemiological analyses of recent and previous EV71 isolates in the WPR indicated that two major genogroups of EV71 are co-circulating in Australia, Malaysia, Singapore, Taiwan and Japan. Recent EV71 isolates in Mainland China constitute a new distinct genetic cluster, subgenogroup C4. Two major lineages of EV71 are the major causative agents of the present HFMD epidemics in the WPR and both are considered to be neurovirulent.

China↗

A comparison of dietary habits among women in Japan and Hawaii.

OBJECTIVE: To compare the dietary habits of Japanese women in Japan with those of Japanese and Caucasian women living in Hawaii. DESIGN: Data from two previous cross-sectional studies conducted within two years in Hawaii and Gifu, Japan were pooled and analysed. Dietary intakes were assessed with validated food-frequency questionnaires and urine samples were collected for isoflavone measurement. SETTING: Participants were recruited through mammography clinics in both locations. SUBJECTS: In Hawaii, 164 Caucasian and 146 Japanese women; in Japan, 206 women. RESULTS: Dietary habits differed considerably by ethnicity and location. In comparison to the Caucasian diet, the diet in Japan was relatively low in fat and high in carbohydrates and protein, whereas the Japanese women in Hawaii reported intermediate intakes. Japanese women in Gifu consumed a diet that was relatively high in fish, soy, eggs and vegetables, and low in fruits, dairy products and meat. In contrast, the Caucasian women consumed the most dairy products and fruits and the Japanese women in Hawaii reported the highest grain and meat intakes. CONCLUSIONS: The diet of Japanese women in Hawaii appeared to be a combination of foods eaten in Japan and the dietary habits of Caucasian women in Hawaii, but eating habits in Japan are also different from traditional nutritional patterns. This study illustrates several problems related to dietary comparisons across populations and provides information for future investigations on chronic disease risk.

Cross-Cultural Comparison↗

Characterization of in vitro and in vivo phenotypes of poliovirus type 1 mutants with reduced viral protein synthesis activity.

Sabin vaccine strains of poliovirus (PV) contain major attenuation determinants in the internal ribosomal entry site (IRES), an area that directs viral protein synthesis. To examine the effect of reduced viral protein synthesis on PV neurovirulence, spacer sequences, consisting of short open reading frames of different lengths, were introduced between the IRES and the initiation codon of viral polyprotein, resulting in PV mutants with reduced viral protein synthesis. These PV mutants had a viral protein synthesis activity 8.8-55 % of that of the parental Mahoney strain as measured in HeLa S3 cells. Only viruses with more than 28 % of the wild-type activity had intact spacer sequences following plaque purification. Mutants with 17 % or 21 % of the wild-type activity were unstable and a mutant with 8.8 % was lethal. The neurovirulence of PV mutants was evaluated in transgenic mice carrying the human PV receptor gene. In this test, mutants with more than 28 % of the wild-type activity remained neurovirulent, while a mutant with 17 % of wild-type activity exhibited a partially attenuated phenotype. This mutant stably replicated in the spinal cord; however, the stability was severely affected during the course of virus infection from the cerebrum to the spinal cord. These results suggest that reduced viral protein synthesis activity as measured in cultured cells (17-55 % of the wild-type activity) is not the main determinant of PV attenuation.

Animals↗

Differential localization of neurons susceptible to enterovirus 71 and poliovirus type 1 in the central nervous system of cynomolgus monkeys after intravenous inoculation.

Poliovirus and enterovirus 71 (EV71) are both neurotropic enteroviruses that cause serious neurological diseases, such as poliomyelitis and encephalitis. The neurovirulence of EV71 in cynomolgus monkeys was demonstrated previously by intraspinal inoculation. In this study, an improved simian model of EV71 infection was established by using intravenous inoculation, which revealed clinical and neuropathological similarities between this model and human cases of encephalitis. Experimental EV71 infection induced direct neurological manifestations, such as tremor, ataxia and brain oedema, but not non-neurological complications, such as pulmonary oedema and cardiac failure. Using this model of EV71 infection, the neurotropic characteristics of the prototype strains of EV71 and poliovirus type 1 (PV1) were compared. Three monkeys were inoculated intravenously with 10(5.5) TCID50 EV71 and all developed neurological disease signs within 4-6 days of inoculation. However, after inoculation with 10(5.5) TCID50 PV1 strain OM1 (PV1-OM1), the major manifestation was flaccid paralysis, starting from the lower limbs 6-9 days post-inoculation. Histopathological and virological analyses of moribund monkeys revealed that disseminated EV71 infection was characterized by severe panencephalitis involving both the pyramidal and extrapyramidal systems. In contrast, the lesions induced by PV1-OM1 were mainly restricted to the pyramidal tract, particularly the spinal motor neurons, thalamus and motor cortex. In conclusion, neuropathological involvement in this model correlated well with the apparent differences in neurological disease induced by EV71 and PV1-OM1. Thus, intravenous inoculation with EV71 is an excellent model to study the neuropathology of EV71 and to evaluate candidate vaccines and potential antiviral agents.

Animals↗

Usefulness of [11C]methionine PET in the diagnosis of dysembryoplastic neuroepithelial tumor with temporal lobe epilepsy.

PURPOSE: We assessed the diagnostic value of [11C]methionine (MET) positron emission tomography (PET) in the differential diagnosis of dysembryoplastic neuroepithelial tumors (DNETs) among benign tumors associated with temporal lobe epilepsy (TLE). METHODS: This series consisted of seven TLE patients with benign tumors in the temporal lobe. After MET-PET study, all seven patients underwent tumor resection along with focus excision. The uptake of tracers was evaluated by the lesion-to-contralateral ratio (L/C ratio) and the standardized uptake value (SUV). We also assessed the relation between MET uptake and proliferation capacity observed in the surgical specimens. RESULTS: Whereas four patients with DNETs did not show high MET uptake visually, the ganglioglioma and gliomas of the remaining three patients were identified as high-MET-uptake lesions. In the DNETs, the SUV ranged from 1.03 to 1.41, and the L/C ratio ranged from 0.99 to 1.14. MET uptake was significantly lower in the patients with DNETs than in the patients with ganglioglioma and brain gliomas (SUV, p = 0.045; L/C ratio, p = 0.0079). The Ki-67 labeling index was 4% in one patient with DNET and 5% in one patient with pleomorphic xanthoastrocytoma (higher labeling index). The higher labeling index was not related to high MET uptake based on the SUV (p = 0.91) and L/C ratio (p = 0.38). CONCLUSIONS: Negative MET uptake in benign temporal lobe tumors with TLE is consistent with a preoperative diagnosis of DNET.

Adolescent↗

Soy, fat and other dietary factors in relation to premenstrual symptoms in Japanese women.

OBJECTIVE: To evaluate the relations of intakes of soy, fat and other dietary components to premenstrual symptoms. DESIGN: Cross sectional study. SETTING: Three colleges and two nursing schools. POPULATION: One hundred and eighty-nine Japanese women aged 19 to 34 years. METHODS: Intakes of nutrients and foods, including soy products and isoflavones, were estimated by a semiquantitative food frequency questionnaire. Change in menstrual cycle symptoms were assessed by the Moos Menstrual Distress Questionnaire (MDQ). MAIN OUTCOME MEASURES: Spearman rank correlation of soy and other dietary factors with changes in MDQ scores between the follicular and the premenstrual phases after controlling for age, marital status, exercise, smoking status, age at menarche and number of days of bleeding. RESULTS: Neither soy product nor isoflavone intake was significantly associated with change in MDQ score in the premenstrual phase. Intakes of total, saturated and monounsaturated fats were significantly correlated with change in scores for total MDQ and subscale 'pain' in the premenstrual phase after controlling for the covariates. Intake of cereals/potatoes/starches was significantly inversely correlated with a change in total MDQ score in the premenstrual phase. CONCLUSIONS: High intake of fats and low intake of foods with high concentration of carbohydrate may be associated with premenstrual symptoms.

Adult↗

Circulation of type 1 vaccine-derived poliovirus in the Philippines in 2001.

In 2001, highly evolved type 1 circulating vaccine-derived poliovirus (cVDPV) was isolated from three acute flaccid paralysis patients and one contact from three separate communities in the Philippines. Complete genomic sequencing of these four cVDPV isolates revealed that the capsid region was derived from the Sabin 1 vaccine strain but most of the noncapsid region was derived from an unidentified enterovirus unrelated to the oral poliovirus vaccine (OPV) strains. The sequences of the cVDPV isolates were closely related to each other, and the isolates had a common recombination site. Most of the genetic and biological properties of the cVDPV isolates were indistinguishable from those of wild polioviruses. However, the most recently identified cVDPV isolate from a healthy contact retained the temperature sensitivity and partial attenuation phenotypes. The sequence relationships among the isolates and Sabin 1 suggested that cVDPV originated from an OPV dose given in 1998 to 1999 and that cVDPV circulated along a narrow chain of transmission. Type 1 cVDPV was last detected in the Philippines in September 2001, and population immunity to polio was raised by extensive OPV campaigns in late 2001 and early 2002.

Base Sequence↗

9HODE stimulates cell proliferation and extracellular matrix synthesis in human mesangial cells via PPARgamma.

Plasma oxidized low-density lipoprotein (OX-LDL) levels are elevated in patients with renal diseases, including diabetic nephropathy. We examined effects of OX-LDL on cell proliferation and extracellular matrix (ECM) production by using normal human mesangial cells. Furthermore, we examined possible involvement of peroxisome proliferator-activated receptor gamma (PPARgamma). Mesangial cell proliferation with OX-LDL, 9-hydroxy-10,12-octadecadienoic acid (9HODE), and 13-hydroxy-9,11-octadecadienoic acid (13HODE), the major components of OX-LDL, were determined by 5-bromo-2'-deoxyuridine (BrdU) or 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) incorporation. The effect of OX-LDL on mesangial cell proliferation with PD98059 pretreatment was determined by BrdU incorporation. Type IV collagen, fibronectin, and PPARgamma expression with OX-LDL or 9HODE or 13HODE was determined by Western blotting. Type IV collagen expression with antisense oligonucleotide against PPARgamma pretreatment was also determined by Western blotting. The effect of PD98059 pretreatment on PPARgamma expression was determined by Western blotting. In mesangial cells exposed to isolated OX-LDL from human plasma, BrdU incorporation was increased, and this increase was deleted by PD98059. Type IV collagen expression was significantly increased by OX-LDL. 9HODE and 13HODE increased BrdU and MTT incorporation into mesangial cells and also increased expressions of Type IV collagen and fibronection, the major components of ECM. PPARgamma expression in mesangial cells was stimulated by 9HODE. The reduction of PPARgamma synthesis by pretreatment of antisense oligonucleotide against PPARgamma remarkably attenuated Type IV collagen synthesis induced by 9HODE. PPARgamma expression induced by 9HODE was also reduced by PD98059 pretreatment. These findings demonstrate that 9HODE, the major component of OX-LDL, stimulates cell proliferation and ECM production of human mesangial cells. In addition, the stimulatory effects are, at least in part, mediated by PPARgamma, which may exist in downstream of ERK1/2 pathway.

Blotting, Western↗

Effect of adjuvant transarterial infusion of anticancer agents after transurethral resection in patients with pT2a muscle invasive transitional cell carcinoma of the bladder: five and ten-year outcome.

Five- and ten-year survival rates in patients who had transurethral resection for pT2aN0M0 muscle invasive transitional cell carcinoma of the bladder was studied with emphasis on the effect of adjuvant transarterial infusions of anticancer agents (TAI). A total of 17 patients out of 290 patients with bladder cancer who had initial treatment in our department between January 1991 and May 2001 were found to be pT2aN0M0 and were included in the present study. Fifteen patients received intravesical instillations of BCG after transurethral resection of the bladder tumor and 8 patients received TAI which was given two weeks after bacillus Calmette-Guerin therapy, with the exception of 1 patient. Five- and ten-year overall survival rates were 76.0% and 52.1%, respectively, and both five- and ten-year cancer-specific survival rates were 76.0% with an average follow up of 71 months. Significant prognostic factor associated with survival rates was only the infiltration pattern of the tumor cells between the alpha and beta group and gamma group (P = 0.0420) in cancer-specific survival rates. The data support conservative management of transurethral resection followed by intravesical instillation of BCG and TAI in patients with pT2a bladder cancer.

Aged↗

Spontaneous regression of a primary cerebral tumor following vasospasm caused by subarachnoid hemorrhage due to rupture of an intracranial aneurysm--case report.

A 40-year-old man demonstrated spontaneous regression of a malignant glioma following vasospasm caused by subarachnoid hemorrhage due to rupture of an intracranial aneurysm. The patient had been treated under a diagnosis of malignant glioma for 5 years. He presented with a ruptured aneurysm manifesting as subarachnoid hemorrhage. Single photon emission computed tomography with N-isopropyl-p-123I-iodoamphetamine and diffusion-weighted magnetic resonance (MR) imaging revealed severe flow reduction due to vasospasm in the bilateral temporoparietal cortical regions, including the tumor. MR imaging performed 5 months later showed marked tumor regression. The present case suggests that treatment targeting angiogenesis of malignant gliomas may be effective as a part of multimodality treatment.

Adult↗

Association between birth weight and serum lipid concentration in premenopausal Japanese women.

BACKGROUND: The relationships between birth weight and serum lipid concentrations in pre-menopausal Japanese women were not well identified and also diet and serum hormone status in these women would be considered. METHODS: A total of 59 premenopausal Japanese women completed a self-administered questionnaire including basic demographic information, disease histories, and menstrual and reproductive histories. They were asked to obtain information on birth weight recorded in mother-and-baby notebook issued by municipality from their mother. Diet was assessed by daily diet records from day 2 through day 10 of the menstrual cycle. Blood sample was collected on day 11 of the cycle to measure serum lipid and hormone concentrations (total and high-density lipoprotein [HDL] cholesterols, triglyceride, estrone, estradiol, and sex hormone-binding globulin). RESULTS: Birth weight was significantly correlated with HDL cholesterol (r = 0.32, p = 0.03), but not with total cholesterol and triglyceride after controlling for age. Neither estrogen nor sex hormone-binding globulin was significantly correlated with serum lipid concentrations after controlling for age and the number of days prior to the next menses. The correlation between birth weight and HDL cholesterol was not affected after additional adjustment for serum estrogen and intakes of protein, calcium, and iron. CONCLUSION: These data suggest that intrauterine growth may be associated with lipid profile.

Adult↗

Clinical outcomes after corpus callosotomy in patients with bihemispheric malformations of cortical development.

OBJECT: Epilepsy in patients with bihemispheric malformations of cortical development (MCD) is typically medically intractable. Focal resection has been reported to be ineffective. Corpus callosotomy has been advocated as a treatment option, but the results have been reported only in several case reports. The authors describe a series of 10 patients with bihemispheric MCDs who underwent total corpus callosotomy. METHODS: The MCDs in these patients included lissencephaly, band heterotopia, perisylvian polymicrogyria, and tuberous sclerosis. Preoperatively all patients suffered disabling drop attacks or intense head drop seizures that caused frequent physical injuries. The follow-up period ranged from 1.4 to 5.8 years (median 3.2 years). Seizure outcome, parental assessment of daily function, and parental satisfaction with outcome were assessed postoperatively. Drop attacks disappeared completely during the entire follow-up period in eight patients and decreased to less than 10% of baseline in one. Other types of seizures were resolved completely in one patient and decreased in seven. Overall daily function improved and parents were satisfied with the surgery-related results in all patients except one who experienced a recurrence of drop attacks. There were no signs of significant and persistent neurological deficits in any case. CONCLUSIONS: Results of total corpus callosotomy in patients with bihemispheric MCDs were favorable in most cases. The procedure was particularly effective against drop attacks causing physical injuries and impaired quality of life in these patients.

Cerebral Cortex↗

[Surgical treatment for temporal lobe epilepsy with preservation of postoperative memory function].

Temporal lobe epilepsy is frequently drug-resistant in adult epilepsy. However, its surgical treatment is very effective and about 70% of operated patients become seizure-free. As preoperative evaluation, analysis of seizure characteristics, scalp EEG with sphenoidal lead, and neuroimaging are most important. When these noninvasive examinations are concordant in focus localization, surgical treatment without prolonged recording by intracranial electrodes become feasible. In spite of good seizure outcome after temporal lobectomy, postoperative impairment of verbal memory has remained to be a long-standing problem. To cope with this ominous complication, we developed a new surgical method of hippocampal transection, based on the principle of multiple subpial transection (MST). Placing a small corticotomy on the anterior part of superior temporal gyrus, the inferior ventricle is opened through suctioning the temporal stem. Intraoperative electrocorticography (ECoG) is recorded over the hippocampus. After the extent of the epileptic area is determined, the alveus is cut with microscissors and the pyramidal layer is transected in parallel with neuronal fibers by a specially designed ring transector. With this procedure, epileptic discharges from the hippocampus can be completely abolished. In all 7 cases undergoing left hippocampal transection, postoperative verbal memory was preserved with excellent seizure outcome.

Adult↗