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T Shimizu

Publications and source records attributed to T Shimizu.

At least 55 records · Page 3Linked to original sources
PubMed2005

Highly selective localization of leukotriene C4 synthase in hypothalamic and extrahypothalamic vasopressin systems of mouse brain.

While leukotriene C4 (LTC4) was originally identified as a potent bronchoconstrictor, the compound has versatile biological activities besides inflammatory reactions. Although the high content of LTC4 has been reported in the hypothalamus and median eminence, the precise localization of the compound remained obscure. To elucidate its possible functions in the neuroendocrine systems, we determined immunohistochemical localization of LTC4 synthase, a key enzyme to produce LTC4 using mouse brains. Light microscopy and confocal laser scanning microscopy showed that LTC4 synthase was selectively localized in the vasopressinergic magnocellular neurons of the hypothalamic paraventricular, supraoptic and suprachiasmatic nuclei and in the retrochiasmatic area, as well as in axons that emanated from these neurons to the pars nervosa of the pituitary gland. At subcellular level, however, LTC4 synthase and arginine vasopressin appeared to localize differently within individual neurons. LTC4 synthase immunoreactivity was also observed in the axons of the extrahypothalamic system including the bed nucleus of the stria terminalis, lateral habenular nucleus, midbrain central gray, medial amygdaloid nucleus and ventral septal area, although this immunoreactivity was relatively minor. The other brain regions did not contain LTC4 synthase immunoreactivity. The distribution of LTC4 synthase did not overlap with that of either oxytocin or luteinizing hormone releasing hormone. Therefore, LTC4 is considered to be involved in neural functions of the brain magnocellular vasopressinergic system such as water retention. LTC4 may also be involved in extrahypothalamic vasopressinergic neural functions including the regulation of learning and memory, social recognition memory, sexual and aggressive behavior, etc.

Animals↗
PubMed2005

Short and long term analysis of heart rate variations in spontaneously hypertensive rats: effects of DSP-4 administration.

The purpose of this study was to investigate whether or not central noradrenergic neurons were involved in the time structure of circadian variation of heart rate (HR) in hypertension. We used spontaneously hypertensive rats (SHR(Izm)) and normotensive controls (Wistar Kyoto rats, WKY(Izm)). We selectively destroyed the noradrenergic neurons in the central nervous system (CNS) by administering noradrenergic neurotoxin, N-(2-chloroethy)-N-ethyl-2-bromobenzylamine (DSP4). Frequency domain measures of variation of HR (VHR) were obtained using the maximum entropy method. The 24-h time frame in VHR is usually dominant in both SHR(Izm) and WKY(Izm). Fourteen days after the administering of DSP4, the mean 24-h systolic arterial pressure (SAP) remained higher in SHR(Izm) than in WKY(Izm). After chemical lesion, ultradian rhythms (12-, 8-, 6-, and 4-h periods) in VHR became more remarkable in both SHR(Izm) and WKY(Izm) than before chemical lesion. Before chemical lesion, an inverse relationship existed between frequency and power spectral density in VHR, demonstrating 1/f(beta) characteristics. The slope of 1/f(beta) in VHR did not differ between SHR(Izm) and WKY(Izm). After the chemical lesion it did not also differ from that of each strain in control period (before lesion). Therefore, the noradrenergic neurons may not affect the time structure of HR in SHR(Izm) and WKY(Izm) for short-term time analysis. However, the intact noradrenergic neurons in CNS may be important to keep normal cardiac autonomic function in SHR(Izm) for long-term analysis.

Animals↗
PubMed2005

Promoter region polymorphism of macrophage migration inhibitory factor is strong risk factor for young onset of extensive alopecia areata.

We have demonstrated that serum macrophage migration inhibitory factor (MIF) was significantly elevated in patients with extensive alopecia areata (AA). Recently, functional polymorphisms have been identified in the MIF promoter region. To address the functional and prognostic relevance of the -173G/C and -794[CATT]5-8 repeat polymorphisms in MIF genes in patients with extensive AA, 113 patients with extensive AA and 194 healthy controls were genotyped. We found that MIF-173*C was a risk factor for early onset (<20 years) of extensive AA (odds ratio for GC heterozygotes with -173G/C was 4.88 (95% CI, 2.04-11.8), P=0.00038; odds ratio for CC homozygotes with -173G/C was 10.42 (95% CI, 2.56-43.5), P=0.0011). We found no statistically significant differences in the genotype frequencies of the -794[CATT]5-8 repeat polymorphism and extensive AA. These results suggest that polymorphisms within the MIF-173*C allele confer an increased risk of susceptibility to the extensive forms of AA, especially with an early onset of disease. MIF is therefore suggested to be closely implicated in the pathogenesis of the more extensive forms of AA.

Adolescent↗
PubMed2005

Prognostic determinants for lung cancer patients with preoperative high serum carcinoembryonic antigen levels.

BACKGROUND: Several reports have indicated that preoperative high serum carcinoembryonic antigen (CEA) levels are associated with poor survival after surgical resection in lung cancer. METHODS: 82 consecutive lung cancer patients with preoperative high serum CEA levels (> 5 ng/mL) were included in this study. Postoperative serum CEA level was also measured. Prognostic indicators were evaluated. RESULTS: Among patients with a preoperative high serum CEA level, a serum CEA level higher than 10 ng/mL, pT status, pN status, and positive pleural lavage cytology findings were unfavorable prognostic indicators, whereas age, gender, smoking status, histologic subtype were not. Postoperative serum CEA levels of all but 2 patients decreased, however those of 28 patients did not return to normal range. Our result showed that patients with postoperative high serum CEA level had poor prognosis. Multivariate analysis demonstrated that pT status, pN status, and postoperative high serum CEA level was an independent prognostic determinant. CONCLUSIONS: In lung cancer patients with preoperative high serum CEA levels, pT status, pN status, and normalization of serum CEA level after surgery are significant prognostic determinants.

Adenocarcinoma↗
PubMed2005

Use of real-time magnetic resonance image guidance in endoscopic sinus surgery.

We evaluated the effectiveness of magnetic resonance image (MRI) guidance using an optical tracking system (MRI-guided therapy: MRT) in performing endoscopic sinus surgery (ESS). The profiles of the fourteen patients in the present study were as follows: eleven with mucocele in the paranasal sinus, one with recurrent chronic sinusitis, one with maxillary cancer, and one with Graves' ophthalmopathy. Preparation of the MRT system required an additional 54 min in cases involving general anesthesia, and an additional 17 min in cases involving local anesthesia, in comparison with corresponding control groups undergoing ESS in a traditional operating room. We developed nonmetal probes that were visualized in a real-time mode and assistive devices for the optical tracking system that were equipped to avoid obstruction caused by surgical instruments as well as by the hands of surgeons. Using these unique devices, anatomic landmarks were visualized using the present MRT system. The prognosis of patients was favorable, and in particular, no patients with sinus mucocele showed a recurrence of their lesions. We concluded that the MRT system used here for performing ESS was beneficial, especially in terms of the intranasal marsupialization of sinus mucoceles and for the verification of orbital contents.

Journal Article↗
PubMed2005

Effects of spaceflight on postnatal development of arterial baroreceptor reflex in rats.

AIM: It has been reported that spaceflight attenuates the arterial baroreceptor reflex. As this reflex function changes dramatically during postnatal development, we hypothesized that space flight depresses the developmental changes of the reflex system. To test this hypothesis, we evaluated the baroreceptor reflex function in rats, which were exposed to a microgravity environment on a space shuttle 9-25 days after birth. METHODS: Baroreceptor reflex sensitivity and the afferent sensitivity were evaluated by measuring heart rate (HR) and aortic nerve activity (ANA) changes in response to an increase in mean arterial pressure (MBP) derived by phenylephrine injection (20-50 microg kg(-1)) under urethane-anaesthesia. RESULTS: Baroreceptor reflex sensitivity (% change of HR/% change of MBP) was lower in the flight group (FLT: -0.19 +/- 0.04, n = 4) than either the asynchronous ground control group (AGC: -0.47 +/- 0.06, n = 6, P < 0.01) or the vivarium group (VIV: -0.41 +/- 0.07, n = 6, P < 0.05). This was similar to the differences of the afferent sensitivity (% change of ANA/% change of MBP) between FLT (2.07 +/- 0.30) and the control groups (AGC: 2.71 +/- 0.22, n.s.; VIV: 3.00 +/- 0.32, P < 0.05). At the end of 30 days of recovery under normal gravity conditions, however, there were no significant group differences in these parameters. conclusion: These results suggest that the space environment attenuates the postnatal development of the arterial baroreceptor reflex function in rats, which may be partially because of a depression of the postnatal development of the baroreceptor afferents. These functional alterations, however, recover to their normal level on re-exposure to the Earth's gravity.

Animals↗
PubMed2005

A Japanese infant with localized ichthyosis linearis circumflexa on the palms and soles harbouring a compound heterozygous mutation in the SPINK5 gene.

We report a 6-month-old Japanese boy showing ichthyosis linearis circumflexa localized on the palms and soles. He showed bamboo hairs and aminoaciduria, and was positive for cow's milk and egg IgE antibodies by radioallergosorbent tests. Trypsin-like hydrolytic activity in the patient's lesional stratum corneum showed an activity seven times higher than that in age-matched controls. DNA analysis showed that the patient harboured the compound heterozygous mutations R790X and 1220+1 G-->C in the SPINK5 gene, compatible with the diagnosis of Netherton syndrome (NS). As the genotype/phenotype correlations in NS have not yet been fully clarified, the position of the premature termination codon in the SPINK5 gene may contribute to explain such a mild form of NS in our patient.

Asian People↗
PubMed2005

Immunological development of preterm infants in early infancy.

To evaluate the immunological development of preterm infants, especially in early infancy, we examined the serum cytokine levels and the expression of Th2 and Th1 chemokine receptors, CCR4 and CCR5, on days 0, 14 and 28 in 16 low birth weight infants (1720.38 +/- 502.80 g) born at less than 37 (33.63 +/- 3.29) weeks of gestation. Using an enzyme-linked immunosorbent assay (ELISA), serum interleukin (IL)-4 levels exhibited an increase on day 14, but decreased to the initial level on day 28 (P < 0.05). The significant elevation of serum transforming growth factor (TGF)-beta levels was confirmed on day 14 (P < 0.05) but decreased to the initial level on day 28 (P < 0.05). The expression of CCR4 and CCR5 were examined using reverse transcription-polymerase chain reaction (RT-PCR) and flow cytometric analysis. The RT-PCR confirmed the expression of CCR5-mRNA soon after birth, while there was no expression of CCR4-mRNA. Thereafter, the expression of CCR4-mRNA increased significantly and reached the level of CCR5-mRNA expression on day 28 (P < 0.05). Flow cytometric analysis, however, revealed that the expression levels of both CCR4 and CCR5 were low at birth. Thus, CCR4(+) CD4(+) cells were significantly increased from days 0-28 (P < 0.05), while CCR5(+) CD4(+) cells were not. Increased IL-4 and TGF-beta synthesis as well as increased CCR4(+) CD4(+) cells suggest that, under extra-maternal circumstances, there is a shift in bias toward Th2 responses even in preterm infants soon after delivery, while they may be capable of developing Th1 mediated responses soon after birth.

Actins↗
PubMed2005

Localization of am3 using EL congenic mouse strains.

EL/Sea mice have 100% incidence of the absence of third molars (M3). Our previous linkage analysis using EL/Sea and MSM/Msf mouse strains provides statistical evidence of a major locus for the absence of M3, designated am3, of EL/Sea at the middle region of chromosome 3. To obtain independent evidence for linkage and more precisely determine the location of the am3 locus, we generated EL/Sea congenic strains for am3 in which the restricted interval of chromosome 3 of EL/Sea was replaced by an MSM/Msf-derived homologue. EL/Sea congenic mice that were either heterozygous or homozygous for the MSM/Msf-derived interval exhibited a significant decrease in the incidence of the absence of third molars, confirming previous genome scan results. These results confine the am3 locus to an approximately 4.4-cM region, and demonstrate that other unmapped genes are also involved in the absence of M3 in EL/Sea mice.

Animals↗
PubMed2005

Alterations in follicular dynamics and steroidogenic abilities induced by heat stress during follicular recruitment in goats.

We investigated the changes in follicular dynamics and steroidogenic activity during heat stress in goats. Adult female goats were exposed to heat stress at 36 degrees C and 70% relative humidity for 48 h and then injected with prostaglandin (PG) F2alpha (the time of PGF2alpha injection was designated as 0 h). In experiment 1, every follicle greater than 2 mm in diameter was monitored by ultrasonography to investigate the follicular dynamics, and plasma concentrations of FSH, LH, progesterone, and oestradiol were measured from -48 h to 120 h. In experiment 2, the follicles were recovered from the goats at 48 h, and the concentration of oestradiol, the aromatase activity, and the LH receptor level in the follicles were determined. In control (non-heat-stressed) goats, ovulatory follicles were mainly recruited from -24 h to 0 h, whereas no follicles recruited during that period were ovulated in the heat-stressed goats. The timing of the recruitment of ovulatory follicles was delayed by heat stress by approximately 24 h. The plasma concentration of oestradiol in the heat-stressed goats was significantly lower from 36 to 54 h compared with the controls, although the concentrations of FSH and progesterone did not differ between the treatments. In addition, the concentration of oestradiol, the aromatase activity, and the LH receptor level in the follicles from heat-stressed goats were significantly lower compared with the controls. These results indicate that heat stress during follicular recruitment suppresses subsequent growth to ovulation, accompanied by decreased LH receptor level and oestradiol synthesis activity in the follicles.

Animals↗
PubMed2005

[Clinical assessment of the thoracic surgical diseases associated with von Recklinghausen's disease].

Type I neurofibromatosis (NF-I), also referred to as von Recklinghausen's disease, is an autosomal dominant disease characterized by neurofibromas and abnormal cutaneous pigmentation (café-au-lait spot). We studied retrospectively the 8 cases operated in our hospital between January 1979 to December 2002, which were complicated with von Recklinghausen's disease and a thoracic surgical disease. The patients were 6 males and 2 females and the age from 16 to 70 (the averaged age was 36 +/- 22). The thoracic diseases were consist of mediastinal tumors (n = 7) and esophageal cancer (n = 1). The operative procedures were tumorectomy (n = 6), subtotal esophagectomy (n = 1), and pericardial cystectomy (n = 1). The mediastinal tumors were neurofibroma (n = 3), malignant schawannoma (n = 1), ganglioneurinoma (n = 2), and pericardial cyst (n = 1). Malignant neoplasms were recognized in 2 cases (25%). The postoperative survival was 10 months for malignant schwannoma, and 8 months for esophageal cancer, and the others were alive. For 1 case of neurofibromas, there was observed to be the reoperated one after the postoperative recurrence. von Recklinghausen's disease are apt to be complicated with thoracic surgical neoplasms, it should be required a careful and systemic exploration especially for malignant neoplasms.

Adolescent↗
PubMed2005

Expression of a CD44 variant and VEGF-C and the implications for lymphatic metastasis and long-term prognosis of human breast cancer.

The aim of the present study was to determine whether expression of the CD44 variant v7-v8 (CD44v7-v8) or vascular endothelial growth factor-C (VEGF-C) is associated with long-term prognosis in breast cancer patients. A 10-year follow-up of 91 patients with primary breast cancer who were previously assessed for CD44 expression was undertaken. Immunohistochemical evaluation of VEGF-C expression was performed in 87 of these patients and their long-term prognosis was assessed. The disease-free and overall survival rates were significantly poorer for the CD44v7-v8-positive patients than for the patients negative for this marker. VEGF-C expression was detected in 38 out of the 87 patients (43.7%) with primary human breast cancer. There were no significant differences in tumor size, histological type, axillary lymph node status, presence of lymphatic or venous invasion, or presence of estrogen receptors and progesterone receptors between the VEGF-C-positive and -negative patients. There were also no significant differences in the disease-free or overall survival rates in these patient groups. In conclusion after the 10-year follow-up, expression of CD44v7-v8 was associated with poor prognosis for breast cancer patients. However, there was no association between VEGF-C expression and the clinicopathological factors or prognosis of breast cancer patients.

Breast Neoplasms↗
PubMed2005

[Primary lung cancer; assessment of the disclosed 5-year survival rate by the Internet website].

The disclosed 5-year survival rate for lung cancer in the Internet website represents a various difference by each institution. The better inferiority of the survival has been listed in a table to compare with other institutions and has been reported in magazines and media with a lack of an enough inspection, i.e., with a sufficient considering of a risk adjustment such as patient's background, operative policy, postoperative adjuvant therapy, and statistical background. We report our outcome of the surgical treatment for primary lung cancer. Of 875 patients treated for lung cancer in our department for 23 years between January 1980 and December 2002, 115 patients containing of 42 cases in 1997 and of 48 ones in 1992 and of 25 ones in 1987 were selected and the accumulated survival analysis was treated by Kaplan-Meier method. Eighty males and 35 females were between 15 and 80-year-old (average 63.2 +/- 11.4). The pathological classification was adenocarcinoma (n=69), squamous cell carcinoma (n=32), and others (n=14). The operative procedures were pneumonectomy (n=14), bilobectomy (n=12), lobectomy (n=85), and wedge resection (n=4). The survival time was from 29 days to 182 months (median survival time was 1471+/- 1180 days, the averaged time was 49 months). The 5-year survival rate was 41.4 +/- 9.1% (n=25) in 1987, 35.6 +/- 6.2% (n=48) in 1992, and 56.0 +/- 7.0% (n=42) in 1987, respectively (log-rank test, p = 0.2555). The 10-year survival rate was 24.1 +/- 7.9% in 1987 and 8.5 +/- 3.6% in 1992, respectively. The 5-year survival rate was as follows: IA 81.0 +/- 8.6% (n=20), IB 73.7 +/- 10.1% (n=19), IIA 57.1 +/- 18.7% (n=7), IIB 55.6 +/- 16.6% (n=9), IIIA 28.6 +/- 7.6% (n=35), IIIB 15.4 +/- 10.0% (n=13), IV 16.7 +/- 10.8% (n=12), respectively. The 5-year survival rate was as follows: male 42.8 +/- 5.3% (n=80), female 63.2 +/- 7.3% (n=35), respectively (p = 0.0147). In regard to the histological classification, the 5-year survival rate was as follows: adenocarcinoma 47.2 +/- 5.9% (n=69), squamous cell carcinoma 50.8 +/- 8.9% (n=32), respectively (p = 0.9012). As a rule of the disclosure on the internet website, we report our survival data by accompanying with minimum parameters such as, patient's background, pathological types, gender, pathological stages, and mean survival rate with standard error. When we compare the 5-year survival rate with other institutes, in considering of a risk adjustment, we would carefully have to estimate the determined survival rate with a standard error.

Adenocarcinoma↗
PubMed2005

[Simulation of lung lobe resection with personal computer].

Various patterns of branching are seen for pulmonary arteries and veins in the lung hilum. However, thoracic surgeons usually cannot expect to discern much anatomical detail preoperatively. If the surgeon can gain an understanding of individual patterns preoperatively, the risks inherent in exposing the pulmonary vessels in the hilum can be avoided, reducing invasiveness. This software will meet the increasing needs of them in video-assisted thoracoscopic surgery (VATS) which prefer lesser dissections of the vessels and bronchus of hilum. We have produced free application software, where we can mark on pulmonary arteries, vein, bronchus and tumor of the successive images of computed tomography (CT). After receiving a compact disk containing 60 images of 2 mm CT slices, from tumor to hilum, in DICOM format, we required only 1 hour to obtain 3-dimensional images for a patient with other free software (Metasequoia LE). Furthermore, with Metasequoia LE, we can simulate cut the vessels and change the figure of them 3-dimensionally. Although the picture image leaves much room for improvement, we believe it is very attractive for residents because they can simulate operations.

Computer Simulation↗
PubMed2005

[Surgery for the thymoma combined with pure red cell aplasia and myasthenia gravis].

UNLABELLED: Pure red cell aplasia (PRCA) and myasthenia gravis (MG) are respectively combined with thymoma, however, these 3 complications are extremely rare coexisted as a clinical triad. A 73-year-old female with mediastinal tumor found in 2000 was pointed out anemia in June 2002. As PRCA was diagnosed by the bone marrow examination, blood transfusion had been performed. By a chest computed tomography (CT), a thymoma in size of 7 x 5 cm in diameter was recognized in the anterior mediastinum. The serum level of anti-acetylcholine receptor antibody was elevated to be 35 nmol/l. MG was simultaneously diagnosed with a decreased power of neck muscle. The extended thymectomy was performed in August 2002, and pathological diagnosis disclosed a 'type AB' by World Health Organization (WHO) classification. After the operation, the decreased power of neck muscle had been improved, however, PRCA had not been remitted in the early-postoperative term. Blood transfusion had been required (2-4 units/1-2 weeks) for the postoperative 7 months' term. A cyclosporin (250 mg/day) as an adjuvant therapy was administered in April 2003. One month later, the patient's serum level of Hb had been over 10 g/dl without blood transfusion. The patient has been followed up with reducing the dose of cyclosporin. CONCLUSIONS: Surgery for a thymoma combined with PRCA and MG was effective for MG but not for PRCA in an early-postoperative term, however, a multimodality therapy with immunosuppressant as a postoperative adjuvant should bring a favorable outcome to patient's clinical data, and the postoperative long-observation must be critical in this case.

Aged↗
PubMed2005

Efficacy and outcomes of clarithromycin treatment for pulmonary MAC disease.

SETTING: Retrospective review of patients with pulmonary Mycobacterium avium complex (MAC) disease treated with clarithromycin. OBJECTIVES: To investigate whether the short-term response to treatment predicts long-term outcomes, and to analyse what explanatory variables are associated with the efficacy and outcome of treatment. DESIGN: Sputum conversion rates in short- and long-term outcomes were evaluated for 111 patients. Respectively 9 and 10 explanatory variables were analysed for their association with both response and outcomes. RESULTS: Eighty-four patients (75.7%) showed good short-term response and 94 (82.0%) showed good long-term outcomes. Women and patients with satisfactory nutrition status showed good short-term response. Patients with small lesions and those treated for >12 months after sputum conversion showed good long-term outcomes. Patients who showed good short-term response, in the group with large lesions, showed significantly good long-term outcomes (P = 0.0382). CONCLUSION: There were differences between prognostic factors reflecting short-term response and long-term outcomes. The short-term response predicts long-term outcomes in certain groups divided by prognostic factor. To establish standard treatment for pulmonary MAC disease, it is important to determine a standardised method of evaluation of treatment taking such factors into consideration.

Adult↗