Biomedical subjects

S Sasaki

Publications and source records attributed to S Sasaki.

At least 55 records · Page 3Linked to original sources

PubMed2004

Salt and salted food intake and subsequent risk of gastric cancer among middle-aged Japanese men and women.

Evidence on the association between salt intake and gastric cancer is sparse, especially in prospective studies. We conducted a population-based prospective study in Japan, where the majority of men has been infected with Helicobacter pylori. A total of 18 684 men and 20 381 women aged 40-59 years who reported their dietary habits and did not report any serious disease at baseline were followed from 1990 to 2001. A total of 486 cases, 358 men and 128 women, with histologically confirmed gastric cancer were documented among them. The quintile category of salt intake was dose-dependently associated with gastric cancer risk in men after adjusting for potential confounding factors (P for trend <0.001), while a trend was not clear in women (P for trend=0.48). Although stratification by study area, with varied salt intake and gastric cancer incidence, attenuated the observed clear associations with salt and salted foods, the frequency categories of highly salted foods such as salted fish roe and salted fish preserves were strongly associated with the risk in both sexes. Restriction of salt and salted food intake is a practical strategy to prevent gastric cancer in areas with high risk.

Age Factors↗

PubMed2004

Anaemia in relation to low bioavailability of dietary iron among school-aged children in the Aral Sea region, Kazakhstan.

This study investigates anaemia related to the sufficiency of dietary iron intake of school-aged children in the Kzyl-Orda region of Kazakhstan. We conducted a cross-sectional study of 97 school-aged children living in Kzyl-Orda. Blood samples were collected for measuring haemoglobin. Dietary intake data were obtained from 24-h dietary recalls. Iron bioavailability was estimated with algorithms adjusting for absorption enhancers (meat, fish and poultry, and vitamin C) and inhibitors (tea and phytates) consumed in the same meal. The median total iron intakes were adequate compared with the median basal iron requirement; however, the median bioavailable iron intakes were well below the median absorbed iron requirement. Available iron was 6.9-7.2% of the total iron intake after adjusting for the absorption enhancers, and was reduced by 3.1-4.4% after adjusting for both enhancers and inhibitors. After adjustment for energy intake, higher iron intake was significantly associated with a decreased prevalence of anaemia (odds ratio, 0.39; 95% confidence interval, 0.16-0.93; P=0.034). Some evidence suggested an association between bioavailable iron intake after adjustment of absorption enhancers and inhibitors (odds ratio, 0.43; 95% confidence interval, 0.18-1.01; P=0.053). In conclusion, low bioavailability of dietary iron seems related to anaemia in the region. Although iron fortification or supplementation programmes can be useful for promoting the anaemia prevention control programme, further efforts for nutritional education suited for family level dietary practice are necessary.

Absorption↗

PubMed2004

Changes in the axonal membrane potential and Ca2+ concentration associated with peripheral nerve grafting after spinal cord injury.

We performed peripheral nerve allografting in rats with spinal cord injury, and measured motor function and axonal membrane potential as well as Ca(2+) concentration of the nerve grafting spinal cord area by using a behavior observation system and a confocal laser-scanning microscope, respectively. In our experiments, we produced a model of peripheral nerve grafting after spinal cord injury by peripheral nerve allografting (sciatic nerve) in rats with spinal cord injury (thoracic cord hemisection). The group with spinal cord injury that underwent peripheral nerve grafting showed improvement in motor function, a significant increase in the axonal action potential, and a slight increase in the Ca(2+) concentration compared with the group that did not undergo nerve grafting.

Animals↗

PubMed2004

[Lung metastasis with a 12 years disease free interval from the first surgery of synovial sarcoma; report of a case].

A 48-year-old woman was admitted for surgery on a lung tumor found incidentally. Her medical history showed a synovial sarcoma of left inguinal region which was resected 12 years ago. We performed segmentectomy of left S4 + 5 to removed the metastatic tumor. Histological examination revealed that the tumor was metastatic synovial sarcoma. Synovial sarcoma can metastasize to lung frequently but such a long disease free interval as 12 years is quite uncommon.

Disease-Free Survival↗

PubMed2004

[Anterior mediastinal mass with hyperthyroidism; report of a case].

The patient was a 27-year-old man who had been diagnosed as having hyperthyroidism and with an anterior mediastinal mass which was reduced in size after anti-thyroid therapy. This mass was thought to be thymic hyperplasia associated with hyperthyroidism. An anterior mediastinal mass accompanying hyperthyroidism should be surgically treated when it dose not regress after an appropriate antithyroid therapy or there is a clinical suspicion of malignancy.

Adult↗

PubMed2004

Effects of expression of hRFI on adenoma formation and tumor progression in colorectal adenoma-carcinoma sequence.

For colorectal carcinomas as well as colonic polyps we investigated the expression of a newly discovered gene, hRFI, which is isolated by the yeast two-hybrid screening using hTid as a bait and expressed highly in esophageal carcinomas. Immunohistochemical staining was performed on 48 colorectal carcinomas and 77 colorectal polyps consisting of 70 adenomas and 7 hyperplastic polyps using the antibody of hRFI. We analyzed the expression of hRFI and the correlation between the percentage of staining of each and their clinico-pathological characteristics. Protein coding by hRFI was specifically and diffusely expressed in most of the cancerous regions of the colorectum. Also, in the early stage of colorectal adenomas, staining of hRFI was focal, and the percentage area of diffuse staining increased as the degree of dysplasia progressed. Although all normal colorectal glands and most hyperplastic polyps (71.4%) showed no staining of hRFI, most colorectal adenomas and carcinomas (93.2%) showed a focal or diffuse staining (P<0.001). Furthermore, the percentage of diffuse staining in carcinomas (81.3%) was significantly higher than in adenomas (5.7%) (P<0.001). hRFI is highly expressed in colorectal carcinomas. In the adenoma-carcinoma sequence, hRFI is involved at the initial tumor formation and its diffuse expression is associated with colorectal carcinogenesis. This evidence suggests that hRFI may act as an oncogenic molecule affecting the apoptotic pathway.

Adenoma↗

PubMed2003

Elastic stiffness of the nuclear-spin system in tetragonal U2D2 nuclear-ordered solid (3)He.

We have measured temperature dependences of sound velocity for both longitudinal and transverse sound in nuclear-ordered U2D2 solid 3He with several crystal orientations along the melting curve. The sound velocity change was proportional to T4 for all sound modes and crystal orientations and was attributed to the nuclear-spin part of the internal energy. We extracted six-independent elastic stiffness of the nuclear-spin part and obtained Grüneisen constants of the spin wave velocity for four-independent strains. Grüneisen constants for compressional strain were larger than those for shear strain. Using the multiple-spin-exchange model, we explain the anisotropy of Grüneisen constants in tetragonal symmetry.

Journal Article↗

PubMed2003

The origin of multiple superconducting gaps in MgB2.

Magnesium diboride, MgB2, has the highest transition temperature (T(c) = 39 K) of the known metallic superconductors. Whether the anomalously high T(c) can be described within the conventional BCS (Bardeen-Cooper-Schrieffer) framework has been debated. The key to understanding superconductivity lies with the 'superconducting energy gap' associated with the formation of the superconducting pairs. Recently, the existence of two kinds of superconducting gaps in MgB2 has been suggested by several experiments; this is in contrast to both conventional and high-T(c) superconductors. A clear demonstration of two gaps has not yet been made because the previous experiments lacked the ability to resolve the momentum of the superconducting electrons. Here we report direct experimental evidence for the two-band superconductivity in MgB2, by separately observing the superconducting gaps of the sigma and pi bands (as well as a surface band). The gaps have distinctly different sizes, which unambiguously establishes MgB2 as a two-gap superconductor.

Journal Article↗

PubMed2003

Surgical repair of tetralogy of Fallot with large conus artery.

The large conus artery transversing the right ventricular outflow tract may cause more confusion and concern in the surgery of tetralogy of Fallot with a small pulmonary annulus than other well-known coronary anomalies. We experienced an infantile case that precipitated into a critical left ventricular failure caused by transection of a large conus artery for the transannular right ventricular outflow tract reconstruction and rescued the patient with an extracorporeal lung-heart-assist system. Preoperative precise diagnosis of coronary anatomy should serve to protect against fatal mistakes, and various techniques for repair must be chosen individually for this subset of anomalies.

Coronary Angiography↗

PubMed2003

Mechanisms of excitatory transmission in circular smooth muscles of the guinea pig seminal vesicle.

PURPOSE: Cellular mechanisms of excitatory neuromuscular transmission in circular smooth muscles of the seminal vesicle were investigated. MATERIALS AND METHODS: Circular smooth muscles of the seminal vesicle of the guinea pig were isolated. Changes in membrane potential produced by transmural nerve stimulation were recorded using intracellular microelectrode techniques. Changes in the intracellular Ca ion concentration induced by transmural nerve stimulation were measured in preparations loaded with Ca indicator fura-PE3. Responses produced by bath applied norepinephrine and alpha,beta-methylene adenosine triphosphate (ATP) were also examined. RESULTS: Transmural nerve stimulation evoked excitatory junction potentials that triggered action potentials and also caused transient increases in [Ca2+] (Ca transients). Nifedipine abolished action potentials, leaving underlying excitatory junction potentials unchanged, and reduced the amplitude of Ca transients. Excitatory junction potentials were blocked by alpha,beta-methylene ATP or guanethidine but not by phentolamine. A train of transmural nerve stimulation evoked oscillatory changes in membrane potential and [Ca2+], which were abolished by phentolamine or inhibited by nifedipine. Nifedipine insensitive components were abolished by cyclopiazonic acid. Norepinephrine depolarized the membrane and elicited oscillatory potentials with an associated elevation in [Ca2+]. These responses were inhibited by nifedipine and abolished by additional application of cyclopiazonic acid. Transient depolarization with an associated increase in [Ca2+] was elicited by alpha,beta-methylene ATP and [Ca2+] responses but no potential changes were inhibited by nifedipine. CONCLUSIONS: Circular smooth muscles of the guinea pig seminal vesicle receive a projection of sympathetic nerves that release norepinephrine to initiate slow depolarization through the activation of alpha-adrenoceptors. These nerves also release ATP to elicit excitatory junction potentials. Neurally released norepinephrine and ATP are increased [Ca2+] by the influx of Ca2+ through L-type Ca2+ channels and also by the release of Ca2+ from internal stores.

Action Potentials↗

PubMed2003

Depolarization waves in the embryonic CNS triggered by multiple sensory inputs and spontaneous activity: optical imaging with a voltage-sensitive dye.

Previously, we discovered a novel type of depolarization wave in the embryonic chick brain by using a multiple-site optical recording technique with a fast voltage-sensitive dye. This depolarization wave traveled widely over almost all the region of the CNS. This profile has raised the possibility that the depolarization wave plays some global roles in development of the CNS, rather than contributing to a specific neuronal circuit formation. To obtain more information concerning this issue, in the present study, we examined whether the depolarization wave was triggered by various types of peripheral nerve inputs. Stimulation applied to the vagus, glossopharyngeal, cochlear and trigeminal nerves evoked widely spreading depolarization waves with similar spatiotemporal distribution patterns. The developmental sequence of wave expression was parallel to the development of the excitatory postsynaptic potentials in each sensory nucleus. The depolarization wave was accompanied by a Ca(2+)-wave, suggesting that not only electrical synchrony, but also large-scale Ca(2+)-transients may affect developmental processes in the embryonic brain. Furthermore, we found that the depolarization wave also occurred spontaneously. The waveform and distribution patterns of the spontaneous optical signals were similar to those of the cranial nerve-evoked depolarization wave. These results demonstrated that the depolarization wave in the embryonic chick brain is triggered by multiple sources of external and endogenous activity. This profile supports the idea that this depolarization wave may not serve as a simple regulator of specific neuronal circuit formation, but might play more global roles in CNS development.

Animals↗

PubMed2003

Self-reported rate of eating correlates with body mass index in 18-y-old Japanese women.

OBJECTIVE: To examine associations between rate of eating and macronutrient and dietary fiber intake, and body mass index (BMI). DESIGN: Cross-sectional study. SUBJECTS: A total of 1695 18-y-old female Japanese dietetic students. MEASUREMENTS: Macronutrient intake (protein, carbohydrate, and fat) and dietary fiber intake were assessed over a 1-month period with a validated, self-administered, diet history questionnaire. Body height and weight and rate of eating (according to five categories) were self-reported. RESULTS: Among the nutrients examined, only dietary fiber intake weakly, but significantly, and negatively correlated with BMI in a multiple regression analysis. The rate of eating showed a significant and positive correlation with BMI. The mean BMI was higher by 2.2, 1.5, 1.0, and 0.5 kg/m(2) in the 'very fast', 'relatively fast', 'medium', and 'relatively slow' groups, respectively, compared with the 'very slow' rate of eating group. This correlation remained evident after adjustment for nutrient intake. CONCLUSIONS: Rate of eating showed a significant and positive correlation with BMI, whereas only dietary fiber intake showed a weak correlation with BMI.

Adolescent↗

PubMed2003

Temperature and thermal stress analysis of a crowned maxillary second premolar tooth using three-dimensional finite element method.

The purpose of this study was to calculate the temperature and thermal stress distribution as a result of hot/cold liquid in the mouth. This numerical study was carried out using three-dimensional finite element models and the tooth model was crowned with Au-Pd alloy, Ni-Cr alloy and porcelain. In the first part of the study, temperature changes as a result of hot/cold liquid in the mouth were calculated. In the second part, the thermal stresses caused by temperature changes were obtained. The tooth was assumed isotropic, homogenous, elastic and unsymmetrical. The authors using fortran 77 prepared all calculation programs. The distribution of temperature and thermal stress were plotted for some critical points.

Bicuspid↗

PubMed2003

Finite element analysis of the temperature and thermal stress in a postrestored tooth.

The finite element method was used to calculate temperature and thermal stress distribution as a result of hot/cold liquid in the mouth. This numerical study was carried out using axisymmetric finite element models and the tooth model was endodontically treated restored with cast post and cores. The two tooth models evaluated were Ti-Ti alloy and NiCr-AuPd alloy as post material and crown material with porcelain. First, temperature changes on the restored tooth as a result of hot/cold liquid in the mouth were calculated and then the thermal stress as a result of temperature changes were carried out. A fortran computer program was developed for this study. The tooth was assumed isotropic, homogenous, elastic and symmetrical. The distribution of temperature and thermal stress versus time were plotted for four critical points.

Dental Amalgam↗

PubMed2003

Management of gestational trophoblastic diseases in Japan--a review.

In Japan we have a standardized protocol for the management of gestational trophoblastic diseases issued by the Japan Society of Obstetrics & Gynecology in 1988. Hydatidiform moles should be treated by evacuating the uterus. Patients must then be followed up until serial weekly serum hCG titres fall to undetectable levels. Our hCG regression curve post-evacuation is quite useful for the detection of persistent trophoblastic diseases. Persistent trophoblastic diseases develop in about 10-15 per cent of patients after molar evacuation in Japan. We classify persistent trophoblastic diseases into three groups: (1) post-molar persistent hCG; (2) invasive mole or metastatic moles; and (3) choriocarcinoma. Investigations into any possible metastases are carried out as soon as possible in affected patients. Post-molar persistent hCG presents no focus or histological findings except persistent elevated hCG, although single agent chemotherapy is required. In the other two groups with focus, it is very difficult to get histological specimens to make accurate diagnoses unless surgery is done. For the selection of the most appropriate chemotherapy, what we call a 'Diagnostic Score' is applied to differentiate choriocarcinoma from invasive moles or metastatic moles clinically in patients falling into these two groups. This unique 'Diagnostic Score' for the detection of choriocarcinoma plays an important role in initial management in our protocol.

Algorithms↗

PubMed2003

Anemia and iron deficiency among schoolchildren in the Aral Sea region, Kazakhstan.

The objectives of this study were to estimate the prevalence of anemia and iron deficiency among schoolchildren in the Aral Sea region of Kazakhstan and to determine the various factors associated with anemia in this population. We conducted a cross-sectional study of randomly selected schoolchildren. Blood samples were collected for measuring hemoglobin (Hb), serum ferritin (SF), total iron binding capacity (TIBC), and other hematological indices, and subjects were screened for anemia and iron deficiency. Associations between Hb concentration and SF, TIBC, anthropometric, and socioeconomic data were evaluated using regression analysis. The prevalence of anemia was 49.8 per cent although levels were mostly mild. Twenty-two per cent of the children were iron depleted (SF < 12 microg/l). Of the anemic children, 32.4 per cent were found to have iron deficiency anemia (anemia with SF < 12 microg/l). There were significant positive correlations between the levels of Hb and SF, but a negative correlation with serum TIBC. Age, mean corpuscular volume (MCV) and SF were found to be significantly related to Hb by stepwise multiple regression analysis. Multiple logistic regression analysis revealed that anemia was independently related to living district, education of father, and child's age. The results suggest that iron deficiency is an important determinant of anemia in this population; however, whole anemia cannot be solely explained by iron deficiency. Further studies are needed for consideration of micronutrients status, parasite infestation, hereditary disorders, and exposure to environmental pollutants.

Adolescent↗

PubMed2003

Renal tubular dysfunction in children living in the Aral Sea Region.

BACKGROUND: The Aral Sea region is a natural area seriously polluted by human activities. Recent surveillance revealed the increased prevalence of diverse chronic diseases in children. AIMS: To investigate the function of renal tubules, which are most at risk of damage as a result of heavy metal intoxication, in children of the Aral Sea region. METHODS: A group of 205 children living in Kazalinsk, close to the Aral Sea, and a group of 187 children living in Zhanakorgan, far from the Aral Sea, were examined by means of random urine samples. Both urinary N-acetyl-beta-D-glucosaminidase (NAG; U/mmol Cr) and beta2 microglobulin (BMG; microg/mmol Cr) were calculated for each subject. RESULTS: Mean urinary NAG and BMG were both significantly higher in Kazalinsk than in Zhanakorgan (NAG: 0.77 (0.58) and 0.62 (0.37) U/mmol Cr; BMG: 41.8 (54.8) and 22.5 (20.4) microg/mmol Cr, respectively; mean (SD), p < 0.01). The number of children with abnormal values of NAG (>1.5 U/mmol Cr) was significantly more prevalent in Kazalinsk than in Zhanakorgan (7.9% and 2.6%, respectively, p < 0.05). CONCLUSION: Renal tubular function of children around the Aral Sea region is profoundly impaired. This should be taken into account when considering the health problems of this area.

Acetylglucosaminidase↗

PubMed2003

Development of immunoglobulin variable heavy chain gene consensus probes with conjugated 3' minor groove binder groups for monitoring minimal residual disease in childhood acute lymphoblastic leukaemia.

AIMS: To develop immunoglobulin heavy chain variable (VH) gene probes that are shorter and more flexible in position for monitoring minimal residual disease (MRD) in childhood leukaemia (ALL), using minor groove binder (MGB) technology. METHODS: All VH germline sequences registered in the database were aligned and the consensus regions were determined. The reliability of the MGB probes was compared with non-MGB probes in all 24 cases of ALL. RESULTS: Ten MGB probes (16 to 18 mers) were designed that enabled all the germline sequences on the database to be analysed, whereas the conventional non-MGB probes (21 to 27 mers) did not allow the analysis of four of the VH1 and five of the VH3 germline sequences. The sequencing results in five of the 24 cases of ALL were not matched to the non-MGB probes. CONCLUSIONS: MGB technology allows shorter probes to be designed, enabling MRD to be detected in childhood ALL. This would provide a considerable reduction in cost for a large MRD study.

Child↗