Search PubMed⌕ Search

Biomedical subjects

M Nakata

Publications and source records attributed to M Nakata.

At least 199 records · Page 11Linked to original sources
PubMed1994

Intestinal absorption of serrapeptase (TSP) in rats.

A sensitive sandwich enzyme immunoassay (e.i.a.) for serrapeptase (TSP), an orally available anti-inflammatory proteinase, was established using affinity-purified anti-TSP rabbit IgG and its Fab' fragment conjugated with horseradish peroxidase as the first and the second antibodies respectively. TSP in the plasma was determined by the e.i.a. after its oral administration (100 mg/kg) to rats. The peak concentration was observed between 30 min and 2 h after administration. TSP in the plasma samples was trapped on a microtitre plate coated with the affinity-purified anti-TSP rabbit IgG, and the hydrolysis of a synthetic fluorogenic substrate, butoxycarbonyl-Glu(benzyloxy)-Ala-Arg-4-methylcoumaryl-7-amide, by the trapped TSP was fluorometrically measured (proteinase assay). The values obtained by the e.i.a. and those obtained by the proteinase assay correlated well for various plasma samples. These results indicate that orally administered TSP was absorbed from the intestinal tract and transferred into the circulation in an enzymically active form.

Administration, Oral↗
PubMed1994

[A case of pulmonary thromboembolism with pulmonary hypertension with marked improvement by oral PGI2 analogue].

The patient was a 71-year-old man with dyspnea and bilateral leg edema. He was admitted to our hospital with worsening of dyspnea and had received therapy for chronic heart failure in another hospital. On admission, chest X-ray film revealed dilatation of the cardiac silhouette (CTR: 58%). Electrocardiogram showed atrial fibrillation and negative T wave in II, III, and aVF. Cardiac arteriogram showed no organic lesions, but pulmonary hypertension, pulmonary artery pressure of 60/21/34 mmHg, right ventricular pressure of 40/9/20 mmHg were recognized in pulmonary hemodynamics. The diagnosis of chronic pulmonary thromboembolism was made on the basis of pulmonary arteriogram findings and multiple defects of lung perfusion scintigram. After administration of oral PGI2 analogue for one month, lung perfusion scintigram and right cardiac pressure were markedly improved.

Administration, Oral↗
PubMed1994

In vitro marginal leakage of Class II composite resin restorations by thermal cycling.

In vitro marginal leakage on class II composite resin restorations by thermal stress was investigated at the cervical, proximal, bucco-lingual, and mesio-distal margins of extracted human premolars. The composite materials used in this study were: (1) Occlusin with Bonding Agent(a), (2) Palfique Light-S with Light Bondb, (3) P-50 with Dentin Primer & Scotchbond 2c, and (4) P-50 with Vitrabond and Scotchbond 2c. Those four groups were representatives of a (l) conventional bonding agent, (2) hydrophilic bonding agent, (3) dentin priming or conditioning agent with a hydrophilic bonding agent, and (4) glass ionomer cement used for a sandwich technique. The number of experimental teeth investigated in each group was ten. The marginal seal among the margins and composite materials was investigated by a dye penetration test using a basic fuchsin solution. The results showed that marginal seals at the cervical margins were found to be improved significantly by the use of dentin bonding materials and methods when compared with a conventional (enamel) bonding agent. However, the proximal margins generally had a less effective marginal seal than the occlusal (bucco-lingual and mesio-distal) margins. In addition, the mesio-distal margins showed a less favorable result than did bucco-lingual ones. These differences among margins might be from the efficacy of a round bevel along the occlusal cavo-surface margin, the different thicknesses of cavity enamel, and the order of light exposure.(ABSTRACT TRUNCATED AT 250 WORDS)

Bisphenol A-Glycidyl Methacrylate↗
PubMed1994

[Studies on MRSA pneumonia as a complication of hematopoietic malignancies].

Recently, the progress of chemotherapy has improved the clinical outcome of chemotherapy for hematopoietic malignancies considerably. However, the incidence of MRSA infections has increased in patients with hematopoietic malignancies, since preventive, multi-drug administration of antibiotics is frequently used in these patients. Moreover, patients with hematopoietic malignancies complicated by MRSA pneumonia have a poor prognosis. We examined lymphocyte subpopulations in bronchoalveolar lavage fluid (BALF) in MRSA pneumonia-complicated patients with hematopoietic malignancies and studied their relationship with the clinical features. We also discuss the cause of their poor prognosis. Of 223 patients with hematopoietic malignancies, 18 (8.1%) were complicated by MRSA pneumonia. Many of those patients had lymphoid malignancies. MRSA pneumonia occurred when neutrophil count was decreased. Most patients had been treated with chemotherapy containing anticancer drugs or with corticosteroid therapy. They had also been treated with third generation cefem antibiotics. We studied lymphocyte subsets in BALF in MRSA pneumonia-complicated patients with non-Hodgkin's lymphoma (NHL) and observed the local changes of the pulmonary immunological system due to NHL itself and due to anti-lymphoma chemotherapy. Our findings suggest the possibility that these immunological changes may play a role in the susceptibility to MRSA pneumonia.

Adult↗
PubMed1993

Food consistency modulates eating volume and speed through brain histamine in rat.

Changes in meal parameters of rats fed with different consistency of food were examined using hard and soft pellets. Meal size and eating speed of the first meal after 1800 h increased significantly in rats fed with soft pellets compared to those fed with hard pellets. Effects of histamine depletion on meals treated with hard or soft pellets were investigated after an intraperitoneal injection of 0.11 mmol/kg alpha-fluoromethylhistidine (FMH), a specific suicide inhibitor of the histamine synthesizing decarboxylase enzyme. When rats were fed with hard pellets, FMH significantly decreased eating speed and prolonged meal duration without affecting meal size. When rats were fed with soft pellets, FMH increased meal size and duration, but not eating speed. The meal parameter of eating speed was significantly decreased and meal size and duration were increased in obese Zuckers, a hereditary histamine-depleted animal model, when compared to their lean littermates. These results indicate that proprioceptive sensation from the oral cavity may regulate meal parameters through histaminergic neurons in the brain.

Animals↗
PubMed1993

Synthesis of gamma-carboxyglutamic acid-containing peptides by the Boc strategy.

gamma-Carboxyglutamic acid (Gla) derivatives having several protecting groups at the gamma-carboxyl function were synthesized and examined for their stabilities and removabilities under the conditions used in peptide synthesis by the Boc strategy. Among them, the cyclohexyl (cHx) group of the Gla residue was found to be stable during the synthesis of the protected peptides, but was quantitatively cleaved by the final HF treatment without decarboxylation. Using Boc-Gla(OcHx)2-OH as a starting material, the synthesis of Gla-containing peptides was achieved by the Boc strategy using a standard HF procedure for the final deprotection.

1-Carboxyglutamic Acid↗
PubMed1993

Glucagon-like peptide-1-(7-36)amide and a rise in cyclic adenosine 3',5'-monophosphate increase cytosolic free Ca2+ in rat pancreatic beta-cells by enhancing Ca2+ channel activity.

Glucagon-like peptide-1 (GLP-1), in the form of either GLP-1-(7-36)amide or GLP-1-(7-37), has been shown to potently stimulate insulin release in a glucose-dependent manner and is suggested to be a physiological incretin. To explore the mechanisms by which GLP-1-(7-36)amide stimulates insulin release, we investigated its action on the cytosolic free Ca2+ concentration ([Ca2+]i) in single rat pancreatic beta-cells by the dual wavelength microfluorometry with fura-2. In the presence of 8.3 mM glucose, GLP-1-(7-36)amide at a concentration as low as 3 x 10(-12) M produced a rapid transient increase in [Ca2+]i in some of the single beta-cells. GLP-1-(7-36)amide at 10(-11) M or more evoked the [Ca2+]i response in the majority of beta-cells. In the presence of 2.8 mM glucose, GLP-1-(7-36)amide was without effect. The [Ca2+]i response to GLP-1-(7-36)amide was completely and reversibly inhibited under Ca(2+)-free conditions and by 1 microM nitrendipine, a blocker of L-type Ca2+ channels. Elevation of cAMP in beta-cells by either 10 microM forskolin, an activator of adenylyl cyclase, or 5 mM (bu)2cAMP (db-cAMP) produced an increase in [Ca2+]i similar to that caused by GLP-1-(7-36)amide. The db-cAMP-induced increase in [Ca2+]i was also completely blocked by nitrendipine. In the continuous presence of GLP-1-(7-36)amide and after the transient [Ca2+]i increase it elicited, db-cAMP failed to evoke the [Ca2+]i response. It is concluded that GLP-1-(7-36)amide at physiological concentrations and a rise in cAMP increase [Ca2+]i in pancreatic beta-cells by enhancing the activity of L-type Ca2+ channels in the beta-cell plasma membrane. It is suggested that the cAMP-operative mechanism is involved in the GLP-1-(7-36)amide action to increase [Ca2+]i in beta-cells.

Animals↗
PubMed1993

[The effect of four recipient strains on intra-uterine growth in mice--birth weight].

The embryo transfer technique is a very powerful tool for detecting intra-uterine effects of dams on prenatal growth of embryos. Embryos of DDD strain were transferred to a recipient of the same strain. Litter size, gestation period and birth weight of newborn offspring were measured. To examine the effect of embryo transfer on the prenatal growth of embryos, these results were compared with those of newborn DDD strain of mice that had developed from non-transferred embryos. Embryos of DDD strain were transferred to four strains of recipients (DDD/Qdj, C3H/Qdj, C57BL/Qdj and DBA/1J Sea). Litter size, gestation period and birth weight of newborn offspring were measured. The four strains of recipients were compared to examine the effect of recipient strain on the prenatal growth of the embryos. The results were as follows. 1. There was no gender difference in birth weight of offspring. 2. A negative correlation (partial regression coefficients: -0.024, P < 0.001 in the transfer and non-transfer groups, and -0.058, P < 0.001, in the four strains of recipients) was observed between litter size and birth weight of newborn offspring, while a positive correlation (partial regression coefficients: 0.068, P < 0.001 in the transfer and non-transfer groups, and 0.071, P < 0.001 in the four strains of recipients) was observed between gestation period and birth weight of newborn offspring. 3. Embryo transfer might affect the intra-uterine growth of transferred embryos. 4. The four different strains of recipients might contribute unequally to the prenatal growth of transferred embryos because of their different intra-uterine conditions.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Synthetic studies of erythromycin derivatives. Synthesis and antimicrobial activities of 3''-EPI-erythromycin A and (9S)-11-dehydroxy-9-deoxo-9-hydroxy-11- oxoerythromycin A.

Two new derivatives, 3''-epi-erythromycin A (2) and (9S)-11-dehydroxy-9-deoxo-9-hydroxy-11-oxoerythromycin A (3), have been synthesized by using glycosylation with glycal (Ferrier rearrangement), bromomethoxylation and bis(tributyltin) oxide-bromine oxidation as the key steps. Their antimicrobial activities were compared with those of erythromycin A (1).

Anti-Bacterial Agents↗
PubMed1993

Trapezius muscle pressure pain threshold and strain in the neck and shoulder regions during repetitive light work.

Perceived musculoskeletal discomfort caused by the repetition of a light work task was examined by rating the perceived musculoskeletal discomfort and measuring the muscle pressure pain threshold. Thirteen healthy female workers performed a repetitive light work task for 120 minutes. Based on the perceived musculoskeletal discomfort during the work task the subjects were assigned to one of two groups, i.e., those who reported most complaints and those who reported fewest complaints. The pressure pain thresholds of the trapezius muscles in the most-complaining group were significantly lower than those in the least-complaining group. The pressure pain threshold was logarithmically correlated both with the perceived musculoskeletal discomfort and with the EMG signal amplitudes.

Adult↗
PubMed1993

[Changes in hemodynamics and mixed venous oxygen saturation during intraoperative harvest of autologous platelet-rich plasma].

Intraoperative harvest and transfusion back of platelet-rich plasma (PRP) are an effective procedure to decrease the requirement of blood transfusion. We selected the right atrium as the site for collection and transfusion back of the blood for the harvest of PRP. We studied changes of the hemodynamics and mixed venous oxygen saturation (SvO2 during the intraoperative harvest of autologous PRP in two patients who were undergoing cardiopulmonary bypass (CPB) surgery. The whole blood was collected, processed and the red blood cells were transfused immediately back to the patients using the Plasma Collection System (Haemonetics Model 50). The procedure was accomplished prior to starting CPB. The PRP product was transfused back into the patients at the completion of CPB. The arterial blood pressure, cardiac output, and SvO2 decreased during the collecting phase and immediately returned to the baseline values during the returning phase. No change was observed in the heart rate and arterial oxygen saturation. We conclude that the usage of right atrium as the site for collection and transfusion back of the blood to harvest PRP is effective and useful, and the continuous monitoring of SvO2 is mandatory for detecting the decline of the cardiac output.

Blood Transfusion, Autologous↗
PubMed1993

[A case of B cell lymphoma with negative findings in both chest X-ray and CT images, but lesions of the bronchial mucosa detected on bronchoscopy].

A 68-year-old woman presented to our hospital on January 7, 1992 with swelling of a right cervical lymph node as the chief complaint. After biopsy of the cervical lymph node, non-Hodgkin's lymphoma was diagnosed (diffuse medium cell type, B cell) and she was hospitalized on January 10. Except for the enlargement of the right cervical lymph node noted at the time of hospitalization, no abnormal findings on examination or in chest X-ray and CT scan were noted. However, at bronchoscopy rubor and swelling of the mucosa of the right second carina and the bifurcation between the left upper division and the lingular bronchus were noted, and biopsy was therefore performed. The histologic appearance of the biopsy tissue was similar to that of the lymph node, showing infiltration by malignant lymphoma. The tumor was diagnosed to be stage IIA of the Ann Arbor classification, and COP-BLAM therapy was commenced on January 15. On January 21, the cervical lymph node was no langer present. At bronchoscopy performed on January 25, the abnormal portion of the bronchi had disappeared, and no infiltration was observed in the biopsied specimen. There have been some reports describing lesions within the bronchi in cases of malignant lymphoma. However, there have been few cases in which no abnormalities were found in the chest X-ray and diagnosis was made by bronchoscopy. Thus, it seems to be useful and important to perform bronchoscopy in order to determine the stage of malignant lymphoma.

Aged↗
PubMed1993

[Bulky mediastinal malignant lymphoma].

The efficacy of treatment of 19 patients with malignant lymphoma presenting with mediastinal tumor was evaluated. They included 7 patients with Hodgkin's disease and 12 with non-Hodgkin's lymphoma (NHL). Numbers of patients with stage I, II, III and IV disease according to Ann-Arbor's classification were 6, 4, 3 and 6, respectively. Stage I patients were treated with CHOP therapy after radiotherapy (RT). Stage II and III patients were treated with RT after COP-BLAM chemotherapy. Stage IV patients were treated with COP-BLAM III regimen. Complete remission was achieved in 16 of 19 patients (84.2%), and partial remission in 2 (10.5%). All patients with Hodgkin's disease and 9 (75%) with NHL attained complete remission. All patients in stage I to III and 3 (50%) in stage IV achieved complete remission. Overall median survival was 66 months. The incidence of bone marrow involvement and bulky mass was significantly different between stage I.II and stage III.IV patients (p < 0.05). These results indicate that combination treatment with RT and chemotherapy with regimens including adriamycin was effective in patients with malignant lymphoma presenting with mediastinal tumor, especially in those without bone marrow infiltration and bulky mass.

Combined Modality Therapy↗
PubMed1992

Effect of immunization with anti-idiotypic antibody to melanoma antigen on lung metastasis in mice.

To determine whether the pulmonary metastases of melanoma cells could be inhibited, C57BL/6 mice were immunized with an anti-idiotypic antibody, 7C4, corresponding to a mouse melanoma antigen. Three groups of mice were compared: 1) 7C4-immunized group which received an injection of 100 micrograms of 7C4 in Freund's complete adjuvant (FCA) subcutaneously on day -21 followed by intraperitoneal injections of the same dose on days -14 and -7,2) adjuvant-treated control group administered with only FCA, and 3) untreated control group. On day 0, 5 x 10(5) of BL6 cells were injected into the caudal vein of all mice. Two weeks later, they were sacrificed and their lungs were removed. The number pulmonary metastatic colonies present on the lung surface were counted and compared among the groups. The length of survival days was also compared. The 7C4-immunized group showed an average of 166 +/- 44 colonies as compared to more than that of 300 colonies in each control groups, and a significant difference was observed (P < 0.01). The immunized group survived significantly longer than the control group (Greenwood's formulation) on day 23 (P < 0.01). Thus the immunization with 7C4 effectively inhibited lung metastasis of melanoma cells. These findings suggest that vaccination with anti-idiotypic antibody to tumor antigen is effective on inhibiting tumor metastasis.

Animals↗
PubMed1992

CD4 and CD8 regulate interleukin 2 responses of T cells.

To characterize the T-cell surface molecules involved in regulation of T-cell interleukin 2 (IL-2) responses, we established several monoclonal antibodies (mAbs) that inhibit IL-2 responses of freshly isolated CD8+ T cells and the IL-2-dependent cell line CTLL-2. Here we show that two inhibitory mAbs are directed against Lyt-2 (CD8 alpha). In fact, all anti-Lyt-2 mAbs tested were able to inhibit the IL-2 response of the Lyt-2- and L3T4-deficient cell line HT-2 after transfection with a Lyt-2 cDNA clone. Similarly, anti-L3T4 mAbs inhibited the IL-2 response of CD4-transfected HT-2 cells. These inhibitory effects of anti-CD4 and anti-CD8 mAbs occur on normal T lymphocytes, since they also were observed with CD4+ and CD8+ T-cell blasts, and are specific for IL-2 responses, since IL-4 responses of CD4- and CD8-transfected HT-2 cells were not affected by the anti-CD4 and anti-CD8 mAbs. The inhibitory effects of anti-CD4 or anti-CD8 mAbs could not be explained by interference with IL-2 binding and depended on CD4 and CD8 crosslinking, because F(ab')2 or Fab plus crosslinking second antibody, but not Fab alone, were effective. A mutant Lyt-2 molecule lacking the cytoplasmic region that mediates p56lck binding could not mediate the inhibitory effect upon crosslinking. These results suggest that CD4 and CD8 mediate negative regulation of T-cell IL-2 responses via cytoplasmically associated p56lck.

Animals↗
PubMed1992

Investigation of the human corpus luteum by ultrasonography: a proposed scheme for clinical investigation.

The corpus luteum was investigated in 18 women undergoing hysterectomy. Preoperative ultrasonography with measurements was performed before the corpus luteum was extirpated, weighed, inspected and the diameters were measured. The concentrations of progesterone and estradiol were also determined in peripheral serum. The ultrasound pictures show that the corpus luteum has a slightly cloudy central part, which can vary from hypoechoic to hyperechoic. The peripheral part (corpus luteum 'wall') has a stronger echo and the maximal and minimal thicknesses can be measured. The results showed correlations between ultrasound measurements and anatomical measurements for wall thickness, outer diameter, inner diameter and wall area of the corpus luteum (n = 12, p < 0.02-0.0001). Moreover, all mid-luteal corpora lutea with a hypoechoic central part (five of 13 women) on ultrasound scan had a cystic central structure. Based on these findings, we suggest that an ultrasound investigation of the corpus luteum in the mid-luteal phase should use the following criteria to classify it into four types. Type a: hypoechoic central part with wall of < 3 mm; type b: hyperechoic central part with wall of < 3 mm; type c: hypoechoic central part with wall of >or= 3 mm; and type d: hyperechoic central part with wall of >or= 3 mm. The finding of a hypoechoic central region with a thin wall (< 3 mm) may indicate corpus luteal insufficiency, since significantly lower serum progesterone levels were found in women with this type of corpus luteum.

Journal Article↗