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Biomedical subjects

I Suzuki

Publications and source records attributed to I Suzuki.

At least 73 records · Page 4Linked to original sources
PubMed1999

Participation of the melanocortin-1 receptor in the UV control of pigmentation.

The cloning of the melanocortin-1 receptor (MC1R) gene from human melanocytes and the demonstration that these cells respond to the melanocortins alpha-melanocyte stimulating hormone (alpha-MSH) and adrenocorticotropic hormone (ACTH) with increased proliferation and melanogenesis have renewed the interest in investigation the physiological role of these hormones in regulating human pigmentation. Alpha-melanocyte stimulating hormone and ACTH are both synthesized in the human epidermis, and their synthesis is upregulated by exposure to ultraviolet radiation (UVR). Activation of the MC1R by ligand binding results in stimulation of cAMP formation, which is a principal mechanism for inducing melanogenesis. The increase in cAMP is required for the pigmentary response of human melanocytes to UVR, and for allowing them to overcome the UVR-induced G1 arrest. Treatment of human melanocytes with alpha-MSH increases eumelanin synthesis, an effect that is expected to enhance photoprotection of the skin. Population studies have revealed more than 20 allelic variants of the MC1R gene. Some of these variants are overexpressed in individuals with skin type I or II, red hair, and poor tanning ability. Future studies will aim at further exploration of the role of these variants in MC1R function, and in determining constitutive human pigmentation, the response to sun exposure, and possibly the susceptibility to skin cancer.

Alleles↗
PubMed1999

Novel characteristic for distinguishing Lactococcus lactis subsp. lactis from subsp. cremoris.

Lactococcus lactis strains were examined for their ability to produce gamma-aminobutyric acid (GABA). Results showed that strains of L. lactis subsp. lactis were able to produce this acid, whereas L. lactis subsp. cremoris were not. GABA production thus represents another effective characteristic for distinguishing L. lactis subsp. lactis from L. lactis subsp. cremoris.

Glutamate Decarboxylase↗
PubMed1999

Nutritional intake of elite Japanese track-and-field athletes.

Mean daily intakes of energy and nutrients were surveyed from 3-day food records for 62 elite Japanese track-and-field athletes (28 males and 34 females) selected to participate in the 1994 Asian Championship games held in Hiroshima, Japan. Mean energy intakes of male and female athletes were 3,141 kcal (+/-592) and 2,508 kcal (+/-537), respectively. Based on the Japanese Recommended Dietary Allowances (JRDAs), long-distance and middle-distance runners had significantly higher energy and macronutrient intakes than did sprinters, jumpers, and throwers. There was no significant difference in micronutrient intake among the different types of athletes. However, of the sprinters, jumpers, and throwers, 15 males (54%) and 22 females (65%) consumed less than the JRDA for at least one micronutrient (i.e., vitamin or mineral). For some athletes, nutritional counseling that provides strategies for increasing food intake is recommended to optimize nutrient intake.

Adolescent↗
PubMed1999

Effect of various ions, pH, and osmotic pressure on oxidation of elemental sulfur by Thiobacillus thiooxidans.

The oxidation of elemental sulfur by Thiobacillus thiooxidans was studied at pH 2.3, 4.5, and 7.0 in the presence of different concentrations of various anions (sulfate, phosphate, chloride, nitrate, and fluoride) and cations (potassium, sodium, lithium, rubidium, and cesium). The results agree with the expected response of this acidophilic bacterium to charge neutralization of colloids by ions, pH-dependent membrane permeability of ions, and osmotic pressure.

Acidithiobacillus thiooxidans↗
PubMed1999

The impact of extranodal spread of lymph node metastases in patients with oral cancer.

A retrospective study of 61 patients with histologically confirmed lymph node metastases was undertaken to evaluate the prognostic significance of extranodal spread (ENS) of metastases on the patterns of treatment failure and survival. ENS was present in 28 (46%) of the 61 patients and it was significantly associated with N stage. T stage, clinical stage, number of positive nodes, level of metastases, mode of treatment, and histological differentiation, however, did not influence the incidence of ENS. The 5-year disease-specific survival rate was 57%. The values for patients with and without ENS were 40% and 72%, respectively, which were statistically significant. The univariate analysis showed that the presence of ENS was a significant predictor of patient survival (P = 0.008). The number and level of positive nodes and postoperative radiotherapy had no prognostic importance. ENS, however, was also associated with an increased risk of distant metastases.

Adult↗
PubMed1999

[Midterm achievement and problems of all municipal health and welfare plans for the elderly in Yamagata Prefecture].

PURPOSE: This study was made for providing information in the preparation of Social Welfare Systems in municipalities. METHODS: Based on seven official reports by Yamagata Prefecture, quantitative data on health and welfare services were analyzed. We investigated the midterm achievement and problems of a Municipal Health and Welfare Plan for the Elderly in all 44 municipalities by mail survey (response rate 100%). The questionnaire included the progress situation of the plan, the existence of an assessment organization, and the characteristics of the plan. RESULTS: Both health service and welfare service achieved targets level to a degree. Concerning the progress situation, "The midterm achievement is not satisfactory" for 65.9% (29 municipalities). The main reasons were "budgets" (93.1%, 27 municipalities) and "lack of manpower" (75.9%, 22 municipalities) all of which indicates "lack of home helpers". 58.6% of all 44 municipalities were reconsidering the plan. In assessment organization existed in 31.8% (14 municipalities) of all municipalities. CONCLUSION: It is necessary that analysis should consider not only use of quantitative data but also qualitative one. The major problems found are that community characteristics were not reflected and the opinion of inhabitants were not considered.

Health Planning↗
PubMed1998

Maximal proliferation of cytotoxic T lymphocytes requires reverse signaling through Fas ligand.

Fas ligand (FasL/CD95L) is best known for its role in delivering apoptotic signals through its receptor, Fas (APO-1/CD95). In this study, we present evidence that FasL has a second role as a signaling receptor. Alloantigen-specific proliferation by multiple FasL- murine CTL lines is depressed compared to that of FasL+ CTL lines. FasL- CTLs kill efficiently on a per recovered cell basis and can achieve wild-type levels of proliferation upon stimulation by optimal doses of anti-CD3, suggesting the lack of a costimulatory signal during antigen stimulation. To test this hypothesis directly, soluble FasIgG, a fusion protein of murine Fas and human IgG1, was added to FasL+ CTLs to demonstrate that blocking cell surface Fas-FasL interactions mimics the depression observed for FasL- CTLs. In addition, plate-bound FasIgG in conjunction with suboptimal anti-CD3 stimulation augments proliferative signals in FasL+ but not FasL- CTLs. In contrast to these results with CD8+ T cells, alloantigen-stimulated FasL- CD4+ T cells proliferate vigorously compared to FasL+ cells. These data demonstrate that reverse signaling through FasL is required for CTLs to achieve maximal proliferation and may provide clues to differences in the homeostatic regulation of activated CD4+ and CD8+ T cells during an immune response.

Animals↗
PubMed1998

[Efficacy of F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) scans in diagnosis of pulmonary nodules].

To evaluate the value of F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) scans, we performed FDG-PET scans in 23 patients with indeterminate pulmonary nodules less than 3 cm in size and analyzed these scans qualitatively and semiquantitatively. Histologic specimens were obtained by thoracoscopic excisional biopsy in 16 patients, CT-guided needle aspiration cytology in three, and bronchoscopic brushing cytology in four. Pathological diagnoses were lung cancer in 16 patients, benign inflammation in six, and malignant lymphoma in one. Sensitivity, specificity and accuracy of the FDG-PET scans were 88% (15/17), 67% (4/6) and 83% (19/23), respectively. There were two false-positive cases (organizing pneumonia and cryptococcosis) and two false-negative ones (slow-growing adenocarcinoma and malignant lymphoma). Although a few false-positive cases of granulomatous disease were yielded, the FDG-PET scans were highly sensitive in the detection of lung cancer. We conclude that the FDG-PET scanning in a useful diagnostic imaging modailty in the management of indeterminate pulmonary nodules.

Adult↗
PubMed1998

Basal ganglia arteriovenous malformation presenting as "writer's cramp".

A 12-year-old girl with a 3-year history of writer's cramp in association with a basal ganglia arteriovenous malformation (AVM) is reported. The lesion was localized to the left globus pallidus and putamen, extending to the adjacent white matter of the frontal lobe. Our experience confirms a common anatomical basis of symptomatic focal dystonia: disruption of the pathways within and adjacent to these structures. Appropriate imaging should be carried out in patients with unexplained movement disorders.

Basal Ganglia↗
PubMed1998

Study on surgical treatment of intractable childhood epilepsy.

We studied the clinical details of 14 children with intractable epilepsies, all of whom underwent epilepsy surgery before age 18 years. All 14 suffered catastrophic seizures, which were resistant to the full range of available medical treatments. The ages at operation ranged from 4 years 7 months to 17 years 2 months, with a mean of 9 years 11 months. In nine patients, the age at onset of epilepsy was less than 2 years. The seizure disorders were classified as temporal lobe epilepsy in two patients, extratemporal lobe epilepsy in 10, and symptomatic generalized epilepsy in two. Eight patients had a hemicorporeal deficit (hemiparesis or hemiplegia) preoperatively. All 14 patients showed localized magnetic resonance imaging (MRI), single photon emission computer tomography (SPECT) and/or positron emission tomography (PET) abnormalities, providing crucial information regarding the epileptic focus. As to the surgical outcomes, four patients became seizure-free and the other 10 showed significant improvement during a mean follow-up period of 2 years 5 months. As to etiology, cortical dysplasia was identified in seven patients. Epilepsy surgery should be considered for intractable childhood epilepsy based on individual clinical characteristics, including seizure status, cognitive development, and evidence indicating location of the seizure focus, rather than age.

Adolescent↗
PubMed1998

Motor activity rhythm in dementia with delirium.

Using an actigraph, the activity patterns in 13 demented patients with delirium were examined. We analyzed the data of the eight patients, wearing the actigraphs for more than 10 days. They were classified into four types: type A, nocturnal delirium type; type B, wandering type; type C, hypobulia type; and type D, lying down type. The day to day activity variation was most prominent in type A and seemingly the least in type B. The dominant period of activity rhythm was nearly 24 h in all cases. Additional 12-h period was observed in type C. Actigraphs might become useful in making therapeutic decisions regarding demented patients with delirium.

Activity Cycles↗
PubMed1998

Control of epilepsy associated with cerebral arteriovenous malformations after radiosurgery.

OBJECTIVE: To investigate the effect of radiosurgery for symptomatic epilepsy associated with cerebral arteriovenous malformations (AVMs). METHODS: Thirty five patients with unruptured epileptogenic AVMs were studied with a mean follow up of 43.0 months. The duration of epilepsy before radiosurgery ranged from 2 months to 21 years (mean 2.8 years). Fifteen patients showed partial seizures; eight of these had associated secondary generalisation. The remaining 20 patients showed only generalised seizures without preceding focal seizures. RESULTS: At the final follow up examination, 28 patients remained seizure free, whereas seizures continued in seven. Variables significantly associated with continuity of seizures after radiosurgery were the number of seizures before therapy (p<0.01) and duration of epilepsy (p<0.05). According to Engel's classification, the 10 patients with intractable seizures before treatment included five with grade I, four with grade III, and one with grade IV. The frequency of seizures began to decrease several months after radiosurgery; much shorter than the time required for morphological change in the AVMs. CONCLUSIONS: Radiosurgery seems to be beneficial for seizure control in patients with unruptured epileptogenic AVM.

Adolescent↗
PubMed1998

Purification, characterization and differentiation-dependent expression of a perchloric acid soluble protein from rat kidney.

We have recently reported the presence of a novel perchloric acid soluble protein in rat liver (PSP1) that inhibits cell-free protein synthesis in a rabbit reticulocyte system. While studying the perchloric acid soluble proteins from different tissues of rats, we found that the kidney protein cross-reacted with antibody against the PSP1. In this investigation, we have purified a perchloric acid soluble protein from the rat kidney and studied its characterization and expression. The protein extracted from the postmitochondrial supernatant fraction with 5% perchloric acid was purified by ammonium sulfate fractionation and CM-Sephadex chromatography. By immunoscreening with the rabbit antisera against the PSP1, we detected a cDNA that contained an open reading frame of 411 bp, encoding a 137 amino-acid protein with a molecular mass of 14,149 daltons. The deduced amino acid sequence was completely identical with that of PSP1 from rat liver. The perchloric acid soluble protein from rat kidney (K-PSP1) also inhibited cell-free protein synthesis in the rabbit reticulocyte lysate system in a different manner than RNase A. Immunohistochemistry showed that the expression of K-PSP1 increased from fetal 17th day to postnatal 4th week, and it remained almost the same until the 7th week of postnatal age. Furthermore, the expression of K-PSP1 in the kidney of the nephrotic rat model was shown to be differentiation dependent. On the other hand, the expression of K-PSP1 in renal tumor cells was downregulated as compared with intact tissue. These results suggest that the expression of K-PSP1 is regulated in a differentiation-dependent manner in the kidney.

Amino Acid Sequence↗
PubMed1998

Serum and bronchoalveolar fluid KL-6 levels in patients with pulmonary alveolar proteinosis.

Pulmonary alveolar proteinosis (PAP) is a disease characterized by the filling of alveolar spaces with periodic acid-Schiff-positive proteinaceous material and by the hypertrophy of type II pneumocytes in the alveolar interstitium. To examine if KL-6, a mucinlike glycoprotein, is useful for the diagnosis of PAP and the estimation of its activity, serum KL-6 levels in patients with PAP were measured by an enzyme-linked immunosorbent assay and compared with those of patients with other lung diseases. Furthermore, to estimate the origin of KL-6 in some patients, measurements of KL-6 levels in bronchoalveolar lavage (BAL) fluid and immunohistochemical staining of the lung tissues with a monoclonal antibody to KL-6 antigen were performed. Serum KL-6 levels in patients with PAP were extremely high and were significantly higher than those in patients with interstitial lung diseases in which elevation of serum KL-6 has been recognized. BAL-fluid KL-6 levels in patients with PAP were higher than serum levels. Both serum and BAL-fluid KL-6 levels in patients with PAP correlated well with the disease activity. Immunohistochemically, positive staining was observed in proliferating type II pneumocytes. These results suggest the usefulness of KL-6 measurement in the diagnosis and estimation of disease activity of PAP.

Antibodies, Monoclonal↗
PubMed1998

Clinical evaluation of a leucocyte-depleting blood cardioplegia filter (BC1B) for elective open-heart surgery.

Activation of leucocytes during extracorporeal circulation has attracted attention in recent years as a cause of reperfusion injury in open-heart surgery patients. In the present study, 40 adult patients undergoing elective open-heart surgery were randomized into two groups: 20 using the Pall BC1B leucocyte-depleting filter for blood cardioplegia (group 1) and the other 20 without the filter (group 2). In order to determine if the filter was effective in protecting the myocardium, CPK-MB and troponin-T (TnT) were measured. In addition, efforts were also made to determine appropriate sites at which the BC1B blood cardioplegia filter should be positioned. There were no significant differences between the two groups in terms of conditions of perfusion. No adverse effects were seen in either group. The total leucocyte reduction rate through the filter was 98.1% with the passage of 2 liters of blood through the filter. A pressure drop of 4.4 +/- 3.2 mmHg was observed through the filter during use. Statistically significant differences were noted between the two groups in CPK-MB (p = 0.031) and TnT (p = 0.004). Findings obtained in previous studies demonstrate that the various advantages of leucocyte reduction, shown in experimental studies, can be translated into clinical advantages. In conclusion, based on the results in this clinical study showing significant difference in CPK-MB and TnT which are known effective indicators for myocardial injury, between leucoreduced and non-leucoreduced group, the Pall BC1B leucocyte-depleting filter for blood cardioplegia has been shown to be effective in alleviating reperfusion injury in open-heart surgery patients.

Adult↗