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S Yamamoto

Publications and source records attributed to S Yamamoto.

At least 37 records · Page 2Linked to original sources

[Review of the surgical treatment in superior sulcus tumor].

The rarity of the superior sulcus tumor has led to varying treatment techniques. Generally, radiation therapy followed by surgery has been used. En bloc resection combined with lobectomy and nodal dissection remains standard therapy. The unique location of this tumor, surgical approach thought to be important. Involvement of the anterior areas such as subclavian vessels can be resected by anterior transcervical approach, and vertebral body or brachial plexus through the classic Shaw Paulson approach. Preoperative computed tomography (CT) or magnetic resonance imaging (MRI) is beneficial to the evaluation of the vessels, nerves, and surgical planning. Recent studies showed that induction concurrent chemoradiation therapy improved the resectability and curability. This article reviews the treatment of superior sulcus tumor.

Combined Modality Therapy↗

[Quality of life of long-term survivors of surgically treated lung cancer].

Quality of life (QOL) of long-term survivors (more than 3 years after surgery) of primary non-small cell lung cancer was studied. QOL was analyzed using European Organization for Research and Treatment of Cancer Quality of Life Questionnaire, 30-Item version 3.0 (QLQ-C30) and Hospital Anxiety and Depression Scale (HADS). Sixty of 91 patients (66%) participated in this study 87 +/- 5 (38-172) months postoperatively. In QLQ-C30, calculated scores of physical (84.0 +/- 2.4), role (81.3 +/- 3.6), cognitive (79.7 +/- 2.6), emotional (86.8 +/- 1.9), and social (91.0 +/- 1.9) functioning, and global QOL (72.6 +/- 2.9) were obtained. Calculated HADS A (anxiety) was 3.3 +/- 0.3 and HADS D (depression) was 4.0 +/- 0.4. Postoperative follow-up duration was correlated with financial impact only. QOL of long-term survivors was influenced by gender histology, marital status, employment status, and academic carrier.

Adult↗

[Clinical features of thoracic injury; special reference to diaphragmatic injury].

UNLABELLED: We investigated the clinical feature of thoracic injury patients, mainly with diaphragmatic injury. From 1993 to 2005, 739 patients with thoracic injury were treated at our life-saving emergency center. There were more blunt trauma patients than penetrating injury patients (693 cases vs 46 cases). Regarding the thoracic injury patients, the causes of trauma were traffic injury in 462 (62.5%), unexpected accident including work place accident in 153 (20.7%), suicide in 90 (12.2%), and assault in 34 (4.6%). As the numbers of injured organs increased, the mortality rate increased. Among 156 patients with cardiopulmonary arrest on admission, 155 patients died. This result suggested that saving the life of patients presenting with cardiopulmonary arrest on admission is extremely difficult. Thirty-eight cases (5.1%) required surgical treatment, and surgery to repair diaphragmatic injury was performed in 14 cases. In 6 cases of diaphragmatic injury, thoracoscopy was performed during the examination and/or surgery. CONCLUSION: Urgently transporting thoracic injury patients to hospital before the onset of cardiopulmonary arrest is therefore essential in order to reduce the mortality rate of these patients. In addition, thoracoscopy is very useful for both examining and treating traumatic diaphragmatic injury patients.

Diaphragm↗

Essential role of Shp2-binding sites on FRS2alpha for corticogenesis and for FGF2-dependent proliferation of neural progenitor cells.

Mammalian corticogenesis occurs through a complex process that includes neurogenesis, in which neural progenitor cells proliferate, differentiate, and migrate. It has been reported recently that neurogenesis occurs in the subventricular zone (SVZ), a region previously thought to be the primary site of gliogenesis. It has been recognized that in the SVZ, intermediate progenitor cells, derived from radial glial cells that are multipotent neural stem cells, produce only neurons. However, the molecular mechanisms underlying the regulation of neural stem cells and intermediate progenitor cells as well as their contribution to overall corticogenesis remain unknown. The docking protein FRS2alpha is a major mediator of signaling by means of FGFs and neurotrophins. FRS2alpha mediates many of its pleiotropic cellular responses by recruiting the adaptor protein Grb2 and the protein tyrosine phosphatase Shp2 upon ligand stimulation. Here, we report that targeted disruption of Shp2-binding sites in FRS2alpha leads to severe impairment in cerebral cortex development in mutant mice. The defect in corticogenesis appears to be due at least in part to abnormalities in intermediate progenitor cells. Genetic evidence is provided that FRS2alpha plays critical roles in the maintenance of intermediate progenitor cells and in neurogenesis in the cerebral cortex. Moreover, FGF2-responsive neurospheres, which are cell aggregates derived from neural stem/progenitor cells (NSPCs), from FRS2alpha mutant mice were smaller than those of WT mice. However, mutant NSPCs were able to self-renew, demonstrating that Shp2-binding sites on FRS2alpha play an important role in NSPC proliferation but are dispensable for NSPC self-renewing capacity after FGF2 stimulation.

Animals↗

An outbreak of food-borne listeriosis due to cheese in Japan, during 2001.

Food-borne outbreaks caused by Listeria monocytogenes have been recognized in US and European countries. Only sporadic cases, of neonatal listeriosis, have been reported in Japan. Since L. monocytogenes has been often isolated from foods in Japan, food-borne outbreaks potentially could have occurred. In February 2001, L. monocytogenes serotype 1/2b was isolated from a washed-type cheese during routine Listeria monitoring of 123 domestic cheeses. Further samples from products and the environments at the plant that produced the contaminated cheese were examined for L. monocytogenes. L. monocytogenes serotype 1/2b was detected in 15 cheese samples, at most probable number that ranged from <30 to 4.6 x 10(9)/100 g, and in environmental samples. Studies with people who had consumed cheese from the plant revealed 86 persons who had been infected with L. monocytogenes. Thirty-eight of those people had developed clinical symptoms of gastroenteritis or the common cold type after the consumption of cheese. Isolates from those patients exhibited the same serotype, pathogenicity for mice and HeLa cells, DNA fingerprinting patterns and PCR amplification patterns. From the epidemiological and genetic evidence, it appeared that the outbreak was caused by cheese. This is the first documented incidence of food-borne listeriosis in Japan.

Cheese↗

Gastroinvasive Helicobacter infection in an Ocelot (Leopardus pardalis).

Highly invasive Helicobacter-like organisms were found in a 19-year-old female ocelot (Leopardus pardalis) with multiple ulcers in the fundic region of the stomach. The bacteria, resembling Helicobacter heilmannii, were located largely within canaliculi or in the cytosol of parietal cells. Except in the ulcerative lesions, parietal cells were hyperplastic, while chief cells and neck mucous cells were reduced in number. The term "gastroinvasive Helicobacter-like organism" was applied. It seems probable that this organism differs from other Helicobacter organisms in pathogenicity, and possible that its behaviour in vitro would help it to evade antibacterial treatment.

Animals↗

Correlation of retinal sensitivity measured with fundus-related microperimetry to visual acuity and retinal thickness in eyes with diabetic macular edema.

AIM: To determine whether significant correlations exist between retinal sensitivity measured by fundus-related microperimetry and the visual acuity and the foveal thickness measured by optical coherence tomography (OCT) in eyes with diabetic macular edema (DME). METHODS: A retrospective chart review of 32 eyes with DME and 17 normal healthy eyes that had undergone fundus-related microperimetry and OCT. The macular sensitivity was measured using the recently introduced fundus-related microperimeter, Micro Perimeter 1. The mean retinal sensitivities within the central 2 degrees and 10 degrees were correlated with the best-corrected visual acuity and OCT-measured foveal retinal thickness. RESULTS: The mean sensitivities in the central 2 degrees and 10 degrees were significantly lower in patients with DME than in normal subjects (P<0.0001). The mean retinal sensitivities in the central 2 degrees and 10 degrees were inversely correlated with visual acuity (r(2)=0.623, P<0.0001; r(2)=0.581, P<0.0001) and foveal thickness (r(2)=0.581, P<0.0001; r(2)=0.551, P<0.0001). CONCLUSIONS: The mean retinal sensitivities measured with fundus-related microperimetry were significantly lower in eyes with DME than in normal eyes. Because a significant correlation of the microperimeter-determined retinal sensitivity to visual acuity and foveal thickness was observed, the retinal sensitivities obtained by fundus-related microperimetry may be another measure that can be used to assess the effects of DME.

Adult↗

Predicting the onset of net carbon uptake by deciduous forests with soil temperature and climate data: a synthesis of FLUXNET data.

We tested the hypothesis that the date of the onset of net carbon uptake by temperate deciduous forest canopies corresponds with the time when the mean daily soil temperature equals the mean annual air temperature. The hypothesis was tested using over 30 site-years of data from 12 field sites where CO(2) exchange is being measured continuously with the eddy covariance method. The sites spanned the geographic range of Europe, North America and Asia and spanned a climate space of 16 degrees C in mean annual temperature. The tested phenology rule was robust and worked well over a 75 day range of the initiation of carbon uptake, starting as early as day 88 near Ione, California to as late as day 147 near Takayama, Japan. Overall, we observed that 64% of variance in the timing when net carbon uptake started was explained by the date when soil temperature matched the mean annual air temperature. We also observed a strong correlation between mean annual air temperature and the day that a deciduous forest starts to be a carbon sink. Consequently we are able to provide a simple phenological rule that can be implemented in regional carbon balance models and be assessed with soil and temperature outputs produced by climate and weather models.

Air↗

Identification of risk factors for the development of complications following extended and superextended lymphadenectomies for gastric cancer.

BACKGROUND: Extended lymphadenectomy for gastric carcinoma has been associated with high mortality and morbidity rates in several multicentre randomized trials. METHODS: Using data from 523 patients registered for a prospective randomized trial comparing extended (D2) and superextended (D3) lymphadenectomies, risk factors for overall complications and major surgical complications (anastomotic leakage, intra-abdominal abscess and pancreatic fistula) were identified by multivariate logistic regression analysis. RESULTS: Mortality and morbidity rates were 0.8 per cent (four of 523) and 24.5 per cent (128 of 523) respectively. Pancreatectomy (relative risk 5.62 (95 per cent confidence interval (c.i.) 1.94 to 16.27)) and prolonged operating time (relative risk 2.65 (95 per cent confidence interval 1.34 to 5.23)) were the most important risk factors for overall complications. A body mass index of 25 kg/m2 or above, pancreatectomy and age greater than 65 years were significant predictors of major surgical complications. CONCLUSION: Pancreatectomy should be reserved for patients with stage T4 disease. Age and obesity should be considered when planning surgery.

Adult↗

Capsid protein genetic analysis and viral spread to the spinal cord in cats experimentally infected with feline calicivirus (FCV).

We investigated primitively the molecular basis of the neural spread of a feline calcivirus isolate (FCV-S) from the spinal cord of a cat that died after manifesting excitation. Experimental infections of cats with three clones from parent virus isolate FCV-S, isolated based on plaque size, were performed, and virus recovery from the spinal cord and the nucleotide and predicted amino acid sequences of the viral capsid protein region (ORF2) were compared. In the experimental infection with the one-time cloned virus (C1L1) isolated from a large plaque, the C1L1 was recovered from the spinal cord. In contrast, seven-times cloned C6L7 (from large plaque) and five-times cloned C5S2 (isolated from small plaque) were not recovered from the spinal cord. Genetic analysis of the capsid protein gene of the three viral clones revealed that four bases were different and two amino acids were different at positions 34 (Val in C6L7 and Ala in C1L1 and C5S2) and 46 (Leu in C6L7 and Pro in C1L1 and C5S2) between C6L7 (with large plaque) and C5S2 (with small plaque). The amino acid at position 434 of C1L1 was different from those of C6L7 and C5S2 (Gly in C1L1, D (Asp) in C6L7 and C5S2). From these results, the plaque size seemed not to be related to the spread of virus to the spinal cord. Clone C1L1, which spread to the spinal cord, had a difference of one amino acid from the other two clones, which may be related to the ability to spread to the spinal cord.

Amino Acid Sequence↗

The linoleic acid derivative FR236924 facilitates hippocampal synaptic transmission by enhancing activity of presynaptic alpha7 acetylcholine receptors on the glutamatergic terminals.

The present study aimed at understanding the effect of FR236924, a newly synthesized linoleic acid derivative with cyclopropane rings instead of cis-double bonds, on hippocampal synaptic transmission in both the in vitro and in vivo systems. FR236924 increased the rate of alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor-mediated miniature excitatory postsynaptic currents, without affecting the amplitude, triggered by nicotine in CA1 pyramidal neurons of rat hippocampal slices, that is inhibited by GF109203X, a selective protein kinase C (PKC) inhibitor or alpha-bungarotoxin, an inhibitor of alpha7 acetylcholine (ACh) receptors. FR236924 stimulated glutamate release from rat hippocampal slices and in the hippocampus of freely behaving rats, and the effect was also inhibited by GF109203X or alpha-bungarotoxin. FR236924 induced a transient huge potentiation followed by a long-lasting potentiation in the slope of field excitatory postsynaptic potentials recorded from the CA1 region of rat hippocampal slices, and the latter effect was blocked by GF109203X or alpha-bungarotoxin. Likewise, the compound persistently facilitated hippocampal synaptic transmission in the CA1 region of the intact rat hippocampus. It is concluded from these results that FR236924 stimulates glutamate release by functionally targeting presynaptic alpha7 ACh receptors on the glutamatergic terminals under the influence of PKC, responsible for the facilitatory action on hippocampal synaptic transmission. This may provide evidence for a link between cis-unsaturated free fatty acids and presynaptic alpha7 ACh receptors in hippocampal synaptic plasticity.

Alkanes↗

Surgical procedures for decompression of excessive shear stress in small-for-size living donor liver transplantation--new hepatic vein reconstruction.

We have reported that acute elevation of portal pressure, reflecting wall shear stress of sinusoidal endothelial cells, triggers liver regeneration after partial hepatectomy and that excessive portal hypertension induces liver failure. For prevention of excessive shear stress in small-for-size living donor liver transplantation (LDLT), we developed a new hepatic vein reconstruction to expand the anastomotic site. Fourteen adult patients, who underwent LDLT, were divided into two groups: previous end-to-end hepatic vein reconstruction in nine patients (group P) and the new method in five patients (group N). The outside middle and left hepatic veins of the graft were incised and enlarged to 40 mm. The vena cava was cut 40 mm longitudinally. The graft was positioned a quarter turn counterclockwise with the hepatic vein of the graft anastomosed end-to-side to the vena cava longitudinally. Postoperative portal pressures and serum total bilirubin levels of these two groups showed portal pressure in group N to rapidly decrease below 25 cm H2O following LDLT. No cases showed posttransplanted hyperbilirubinemia above 10 mg/dL in group N; however, all cases were small-for-size grafts. Moreover, serum total bilirubin levels in group N were significantly lower than those in group P. This procedure is simple despite not using a venous patch. If the hepatic vein is narrow or obstructed, such as in Budd-Chiari syndrome, the procedure is applicable. Even in small-for-size grafts, excessive tension did not occurred at the portal vein or hepatic artery anastomoses. Moreover, it is possible to avoid outflow block and posttransplanted hyperbilirubinemia.

Adult↗

Biliary reconstruction and complications of left lobe living donor liver transplantation.

Postoperative biliary tract complications remain one of the most serious problems facing patients who undergo living donor liver transplantation. The aim of this study was to analyze the clinical implications of three methods of biliary reconstruction in left lobe adult living donor liver transplantation. We retrospectively compared three groups of patients who underwent various biliary reconstructions: those who had Roux-en-Y hepaticojejunostomy (HJ) (n = 11); duct to duct hepaticohepaticostomy (HH) with an external stent (n = 11); or HH with T-tube (n = 6). The median follow-up for each group was 29, 28, and 8 months, respectively. Bile leaks were observed in 45.5% of both the HJ and the HH with external stent groups. Biliary anastomotic strictures occurred in 9.1% of the Roux-en-Y HJ patients and in 27.2% of those who had HH with an external stent. No biliary complications were observed in the HH over a T-tube group (P = .049). Biliary reconstruction using HH with a T-tube may decrease the incidence of biliary complications. Despite the relatively short follow-up, these encouraging preliminary results warrant further studies of this biliary reconstruction technique for left lobe adult living donor liver transplantations.

Anastomosis, Roux-en-Y↗

Obesity is associated with increased risk of allergy in Vietnamese adolescents.

BACKGROUND: The prevalence of allergic diseases has remarkably increased in the last decades in tandem with the number of obese individuals. Results of studies on obesity and allergic diseases are controversial, and most of them are related to asthma and asthma-like symptoms. OBJECTIVE: In our study, we evaluated the association of several obesity indices and the prevalence of allergic diseases, including bronchial asthma, allergic rhino-conjunctivitis, atopic dermatitis and food allergy. DESIGN: Cross-sectional study. RESULTS: From a total of 1185 adolescents (49.3% boys) aged 12 to 17 y old, 19.3% reported a physician-diagnosed allergic disease, and 35.3% reported undiagnosed allergic symptoms. Logistic regression analysis revealed a higher risk of allergy in children of middle (OR = 2.02, CI: 1.12-3.64) and high (OR = 2.40, CI: 1.25-4.61) compared to low socioeconomic status, in subjects reporting industrial emissions in the neighborhood (OR = 2.19, CI: 1.40-3.41), and in adolescents with parental history of allergy (OR = 1.92, CI: 1.26-2.92). Body mass index (BMI) and percentage of body fat (%BF) were significantly related to allergy (OR = 1.16, CI: 1.01-1.34 for BMI; OR = 1.03, CI: 1.01-1.06 for %BF). After controlling for socioeconomic status, industrial emissions and parental history of allergy, only %BF remained statistically significant (OR = 1.03, CI: 1.01-1.06). Food allergy was not related to obesity in our study population, and when adolescents with food allergy were excluded from the analysis, the odds of having allergy increased 28% with each increase in SD of BMI (OR = 1.28, CI: 1.05-1.57) and 5% for each unit increase in the percentage of body fat (OR = 1.05, CI: 1.01-1.08). CONCLUSION: In conclusion, being overweight was associated with an increased risk of allergy in our study population. Our results point towards an association between being overweight and rhino-conjunctivitis, but not food allergy. No association was observed with other allergic diseases.

Adolescent↗

FAO/WHO/UNU equations overestimate resting metabolic rate in Vietnamese adults.

OBJECTIVE: To evaluate the FAO/WHO/UNU equations for predicting resting metabolic rate (RMR) in Vietnamese adults. DESIGN: A cross-sectional study with healthy subjects was carried out at the Basic Nutrition Department, National Institute of Nutrition, Vietnam. RMR was measured by indirect calorimetry, and anthropometric indices were recorded. Equations derived by linear regression of RMR vs body weight were compared to the FAO/WHO/UNU 1985 predictive equations. SUBJECTS: A total of 188 subjects (98 males and 90 females) had a normal body mass index (BMI) and were divided into four groups by sex and age (male and female subjects 18-29 and 30-60 y old). RESULTS: Mean RMR (MJ/kg/day) in males was lightly significant by higher than that in female subjects in the 18-29 y old age group (0.1074+/-0.0100 vs 0.0965+/-0.0123) and the same result was seen in the 30-60 y old group (0.1018+/-0.0114 vs 0.0922+/-0.0129). However, differences were not statistically significant in the two age groups. Compared to the FAO/WHO/UNU equation, our findings were 7.4, 9.0, 11.7, and 13.5% lower in the four groups, respectively (P < 0.001). CONCLUSION: Our findings suggest that the FAO/WHO/UNU equations may overestimate RMR in Vietnamese adults. Further studies examining the relationship between body weight and RMR are needed, and establishing new predictive equations for RMR in Vietnamese should be a priority.

Adolescent↗

Feeding practice among younger Tibetan children living at high altitudes.

OBJECTIVE: Few published data are available on the feeding practice of younger children in Tibet. Our study investigated feeding pattern of younger Tibetan children. DESIGN AND SUBJECTS: The study was a cross-sectional survey conducted in Tibet. A sample of 1655 children younger than 36 months old and their mothers was obtained by stratified multistage cluster random sampling method. Mothers were interviewed to collect information on feeding practice by a designed family questionnaire including initial time and duration of breastfeeding and time, frequency and types of complementary foods introduced. RESULTS: Most of the children was ever or being breastfed at the time of interview. The median duration of breastfeeding was 26 months. The prevalence of almost exclusive breastfeeding for 4 months was 20.1%. Mothers' age and education, child's residence, and introduction of egg, fresh milk and milk powder were strongly associated with the duration of breastfeeding. The partial feeding was a main pattern in the first 6 months of life. Zanban and porridge were offered at about 1 month after birth. By 6th month, less than 25% of children were fed protein foods such as egg and meats and only near 20% of children were fed fresh vegetables. Bean products, fish and chicken were seldom offered to children. CONCLUSIONS: We conclude that although they were breastfed for long time, complementary feeding practice of Tibetan children was disadvantaged, especially of rural children. Improvement of monotonous complementary foods and timely introduction should be stressed in local programmatic nutritional interventions.

Altitude↗