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Biomedical subjects

S Murakami

Publications and source records attributed to S Murakami.

At least 487 records · Page 27Linked to original sources
PubMed1994

[A case of early hilar lung cancer combined with intralobar pulmonary sequestration, both of which were treated by limited lung resection].

A 59-year-old man complained of fever due to infection in the intralobar pulmonary sequestration. On bronchoscopic examination, squamous cell carcinoma was found out at orifice of the left upper division bronchus. His pre-operative pulmonary function test showed low pulmonary reserve because of myelopathy. He underwent left S1 + 2 + S3 sleeve segmentectomy and S9 + 10 segmentectomy for intralobar pulmonary sequestration. He is well without any evidence of recurrence 10 months after surgery.

Bronchopulmonary Sequestration↗
PubMed1994

[Combined resection and replacement of the superior vena cava with an expanded polytetrafluoroethylene graft in surgery of pulmonary-mediastinal malignant tumor].

Combined resection and replacement of the superior vena cava with an expanded polytetrafluoroethylene graft was performed in 7 patients. Five patients had lung cancer, and 2 had malignant thymoma. During operation, total clamping of the superior vena cava was required in 2 patients, and partial clamping of the superior vena cava or clamping of the innominate vein in 5. The reconstruction procedures were as follows; the superior vena cava or bilateral innominate veins with a graft in 4 patients, bilateral innominate veins with 2 grafts in 1, and one of the innominate veins with a graft in 2. There was no operative death. Edema of face, neck and arms appeared in 6 patients postoperatively, but it disappeared in 3-10 days. Phlebogram which was obtained in 5 patients demonstrated patency of the grafts in 4 and well-developed collateral drainage in 1. Postoperative survival time was 1-27 months, and 3 patients are alive. No superior vena cava syndrome was recognized in long term observation of any patient.

Aged↗
PubMed1993

CD44 expression on activated B cells. Differential capacity for CD44-dependent binding to hyaluronic acid.

CD44 expression and the functional capacity for CD44-dependent binding of hyaluronic acid (HA) were analyzed on unstimulated B cells and on B cells stimulated with a variety of polyclonal B cell activators. Whereas essentially all LPS-activated and anti-IgD-dextran-activated B cells and a subpopulation of IL-5-activated B cells expressed increased levels of cell surface CD44 relative to unstimulated B cells, only IL-5-activated CD44hi B cells constitutively bound to FITC-conjugated hyaluronic acid (FITC-HA). Preincubation of LPS or anti-IgD-dextran-activated B cells with the CD44-specific mAb IRAWB14.4 (IRA) induced a high degree of FITC-HA binding in these populations; preincubation of unstimulated B cells with this CD44-specific mAb induced minimal FITC-HA binding. In contrast, preincubation with mAb IRA failed to induce FITC-HA binding by the IL-5-activated CD44lo B cell subset. Neither the amount of constitutive FITC-HA binding nor the level of IRA-inducible FITC-HA binding correlated simply with the overall level of CD44 expressed by the different B cell populations. Biochemical analysis of immunoprecipitated CD44 molecules revealed that relative to CD44 isolated from all other populations examined, CD44 isolated from IL-5-activated B cells was of a lower molecular weight. Treatment with N-Glycanase eliminated this observed difference in molecular weight, indicating that it reflected differences in N-glycosylation of CD44 on activated B cells. Polymerase chain reaction analysis of amplified cDNA showed that each B cell population expressed a common dominant CD44 mRNA. These findings suggest that post-translational modification of CD44 and/or differential association of CD44 with other cellular components plays a critical role in activation-specific ligand binding by CD44.

Animals↗
PubMed1993

Inhibitory effect of interleukin 4 on production of interleukin 6 by adult T-cell leukemia cells.

Freshly isolated leukemic cells from patients with adult T-cell leukemia (ATL) produce high levels of interleukin 6 (IL-6), which is suggested to play an important role in thrombocytosis, elevation of C-reactive protein, and hypercalcemia in ATL. In this study, we investigated the effects of T-cell growth factors such as interleukin 2 (IL-2) and interleukin 4 (IL-4) on IL-6 production by ATL cells in vitro. Although IL-2 and/or IL-4 enhanced the cell proliferation of freshly isolated ATL cells from seven of nine patients, IL-2 did not affect the IL-6 release in most cases. In contrast, another T-cell tropic factor, IL-4 markedly inhibited the release of IL-6 in the conditioned medium in all cases. This IL-4-mediated inhibition of IL-6 release was completely abrogated by the addition of anti-IL-4 monoclonal antibody. Time course experiments demonstrated that IL-4 reduced the secretion of IL-6 for a prolonged period of time (more than 72 h). By Northern analysis, IL-4 reduced the transcription level of IL-6 mRNA. Furthermore, by flow cytofluorometry with the use of anti-human IL-4 receptor monoclonal antibody, ATL cells showed the significant level of IL-4 receptor on their cell surfaces without any stimulation. These data suggest that IL-4 may play an important regulatory role in the production of IL-6 in ATL.

Aged↗
PubMed1993

Structure and function of the intracellular portion of the mouse interleukin 1 receptor (type I). Determining the essential region for transducing signals to activate the interleukin 8 gene.

The structural and functional relationships of the intracellular portion of mouse interleukin 1 receptor (muIL-1R) type I were examined with regard to activation of the human IL-8 gene in the Jurkat T cell line. C-terminal deletion mutations of muIL-1R revealed that the C-terminal boundary for receptor function is localized between 28 and 42 amino acids from the C-terminal end. The internal deletion mutants between amino acids 364 and 474 had a loss of activity, demonstrating the requirement for a large region of the mIL-1R cytoplasmic portion for receptor function. Amino acid substitution revealed that the putative nuclear localization elements (amino acids at 429-433, 523-527, and 507-519) and putative protein kinase C or A acceptor sites (Ser-431, Ser-509, Ser-528) do not participate in IL-1 signaling to induce IL-8 gene expression. A truncated mutation within the segment, which possesses homology with gp130, beta chain of IL-6R, or a point mutation of box 1- and box 2-like elements within the gp130 homologous segment, abolished the capacity to induce IL-8 gene expression, suggesting similar structural requirements in the cytoplasmic portion of several cytokine receptors.

Amino Acid Sequence↗
PubMed1993

Inversion of chromosome 16 and eosinophilia in refractory anemia with ring sideroblasts: report of a case.

A 72-year-old male who was admitted to our hospital with severe anemia was diagnosed as refractory anemia with ring sideroblasts (RARS), according to the French-American-British (FAB) classification of myelodysplastic syndromes (MDS). The patient showed persistent eosinophilia with no definite signs of either allergy or a parasitic infection. Chromosomal analysis of bone marrow cells revealed inv(16)(p13q22), a known characteristic of M4Eo acute myeloid leukemia (AML) in the FAB classification. This patient didn't exhibit leukemic transformation during his 20-month clinical course, nor was any found at autopsy. Therefore, this is the first case of RARS to speculate that the chromosomal characteristic inv(16)(p13q22) might be specific for eosinophilia rather than AML.

Aged↗
PubMed1993

Propranolol has direct antithyroid activity: inhibition of iodide transport in cultured thyroid follicles.

The effect of propranolol on the process of thyroid hormone formation was studied in a physiological culture system. Porcine thyroid follicles were preincubated with propranolol for 24 h. Iodide transport, iodine organification, and de novo thyroid hormone formation were measured by incubating these follicles with the mixture of carrier-free 0.1 microCi Na125I and 50 nM NaI for 2 to 6 h at 37 degrees C. A concentration of propranolol greater than 100 microM inhibited iodide transport in a dose-dependent manner; this inhibition was non-competitive with iodide and independent of thyrotropin (TSH). Reduced iodine organification and thyroid hormone formation was seen with 150 microM propranolol or greater. The inhibitory action of propranolol was not caused by beta-blocking activity, since D-propranolol (devoid of beta-blocking activity) inhibited iodide transport, and other beta-blockers (metoprolol, atenolol, and labetalol) did not inhibit iodide transport. The inhibition of iodide transport was most likely caused by membrane stabilizing activity since quinidine, which possesses the same membrane stabilizing activity as propranolol, also inhibited iodide transport. TSH-mediated cAMP generation and Na+K+ ATPase activity, membrane functions for iodide transport, were unaffected by propranolol. Our study has shown, for the first time, that propranolol has a direct antithyroid action, namely inhibition of iodide transport in the intact thyroid follicle.

Adrenergic beta-Antagonists↗
PubMed1993

Absence of nonpercutaneous transmission of hepatitis C virus in a colony of chimpanzees.

Transmission of hepatitis C virus (HCV) was studied in a colony of 85 chimpanzees using assays for anti-HCV and HCV-RNA. Thirteen of the 85 sera were positive for anti-HCV, and 12 of the 13 were also positive for HCV-RNA. All of the anti-HCV positive sera except one were obtained from chimpanzees which had been inoculated with non-A, non-B hepatitis virus. On the other hand, only one of 63 sera of chimpanzees without history of experimental infection of the virus was positive for anti-HCV. Transmission to this chimpanzee was thought to be a needle contaminated with HCV. All 39 samples of chimpanzees born in the center were negative for both anti-HCV and HCV-RNA. Sixteen of their mothers had undergone experimental infection, and 6 of them were positive for both anti-HCV and HCV-RNA. These results suggest that nonpercutaneous transmission, including sexual and mother-to-infant transmissions, is not an important mode of transmission. If these findings apply to humans, definition of inapparent sources of the infection is needed.

Animals↗
PubMed1993

A case of renal cell carcinoma with metastasis to the thyroid gland and concomitant early gastric cancer.

Metastatic lesions from renal cell carcinoma are commonly recognized in the lung and bone, however, thyroid metastasis has rarely been reported in the literature. We present herein a case of a man with lung and thyroid metastatic tumors from renal cell carcinoma. Although making a preoperative diagnosis of thyroid metastasis is difficult because there is no established diagnostic criteria, we were able to identify this thyroid lesion as a metastatic tumor from renal cell carcinoma by the pathological findings. Interestingly, hypercalcemia was recognized in this patient whose serum parathyroid hormone (PTH) level was not increased. Moreover, this patient also had early gastric cancer simultaneously, being a so-called 'double cancer'. After surgical resection of the right kidney and stomach, interferon was administered without any efficacy against the metastatic lesions of the lung and thyroid gland.

Carcinoma, Renal Cell↗
PubMed1993

Sequence analysis of putative structural regions of hepatitis C virus isolated from 5 Japanese patients with hepatocellular carcinoma.

The nucleotide sequences of the 5'-portion of the HCV genome, consisting of 2672 nucleotides, were determined by analysis of clones derived from 5 different patients with liver cirrhosis and hepatocellular carcinoma. Comparison of 5 genomes and 8 isolates already reported demonstrated the significant genome diversity in the structural regions. Genetic divergence was outstanding in the envelope regions (E1 and NS1/E2, > 59.7% identity) in contrast to the sequence conservation of the 5' non-coding (> 93.8% identity) or core regions (> 82.0% identity). Although hypervariable regions were found in the NS1/E2 region as reported, hydropathicity was maintained for all clones, reflecting the biological functions of these regions.

Amino Acid Sequence↗
PubMed1993

Displacement of lidocaine from the lung after bolus injection of bupivacaine.

The purpose of this study was to determine whether lidocaine was displaced from the lung after bolus injection of bupivacaine. Fourteen anesthetized rabbits were randomly assigned to either a bupivacaine or a control group. Lidocaine was infused at a rate of 10 mg.kg-1 x hr-1. After one hour of infusion, a bolus of bupivacaine (1 mg.kg-1) in normal saline (0.2 ml.kg-1) was injected into the central venous circulation in the bupivacaine group. The control group was injected with normal saline. After bolus injection, arterial blood samples were collected serially from an internal carotid artery at 1.2-sec intervals for 24 sec. The baseline concentration of lidocaine was 3.0 +/- 0.1 micrograms.ml-1 in the bupivacaine group and 3.2 +/- 0.1 micrograms.ml-1 in the control group (NS). Arterial concentrations of lidocaine increased to a maximum of 4.7 +/- 0.2 micrograms.ml-1 in the bupivacaine group (P = 0.0001). No increases were seen in the control group. These findings indicate that lidocaine was displaced from the lung into the blood after bolus injection of bupivacaine. The amount of lidocaine displaced during the first passage of bupivacaine through the lung was calculated to be 92.3 +/- 9.7 micrograms. It is concluded that lidocaine is displaced from the lung after bolus injection of bupivacaine.

Animals↗
PubMed1993

Magnetic field responses to visual stimulation in human parietal association cortex.

The neural activities of the parietal association cortex were studied in humans through the use of a 37-channel SQUID magnetometer system. The magnetic field responses were recorded in the parietal association cortex following visual stimulation with LED light. Main responses peaking at about 120, 170 and 220 msec after LED onset were observed. The estimated current dipole sources of the magnetic field responses at latencies of 160-190 and 210-270 msec were revealed to be located in the intraparietal sulcus. A change in the magnetic field responses with the eye position was found in the amplitude.

Adult↗
PubMed1993

Evaluation of surgical treatment of pyothorax with special reference to the usefulness of the omental pedicle flap method.

The operative results in a series of 17 patients with pyothorax were reviewed. Of these, 10 had chronic empyema (group 1), and 7 had postoperative empyema (group 2). A single-stage operation was performed in eight patients in group 1 (decortication in six, thoracoplasty in one, omental plombage in one) and in all patients in group 2 (omentopexy in five, thoracoplasty in two). Two-stage procedures were performed in two patients in group 1. We obtained favorable postoperative results in eight patients in group 1, and in four patients in group 2. In our series, good results were not obtained by thoracoplasty alone; however, satisfactory results were achieved by short-term management in patients treated with the omental method. We think this series demonstrates the value of the omental pedicle flap method, which prevents loss of function due to a defective organ and offers excellent therapeutic results following an easy operative procedure. Further active application of this method can be expected in the management of thoracic disorders.

Adult↗
PubMed1993

Tracheal reconstruction after lower tracheal resection using the inverted right bronchus--an experimental study.

An experimental study of tracheal reconstruction after lower tracheal resection using the inverted bronchus was performed in 8 dogs. After right upper lobectomy, the five cartilage rings of the lower trachea, ending three cartilage rings above the carina, was circumferentially resected; the right bronchus was transected just above the right second carina, the portion of the transected trachea above the carina was closed, and the right bronchus was inverted. The peripheral end of the upper trachea was anastomosed to the inverted right bronchus, and the intermediate bronchus was anastomosed to the lateral wall of the left bronchus. After completion of the airway reconstruction, the anastomotic site was wrapped with an omental flap. Although anastomotic complication were observed in two dogs, all the dogs survived the operation. Bronchoscopically and histopathologically, the findings for the inverted bronchus were almost normal three to four weeks after the operation. The clinical relevance of such a tracheal reconstruction is discussed.

Anastomosis, Surgical↗
PubMed1993

Enhancing effect of interleukin-2 on production of parathyroid hormone-related protein by adult T-cell leukemia cells.

Leukemic cells from patients with adult T-cell leukemia (ATL) can produce a calcium-regulating protein, parathyroid hormone-related protein (PTHrP). Moreover, it has been reported that ATL cells produce some cytokines besides PTHrP and that these cells respond to the T-cell growth factors, interleukin-2 (IL-2) and interleukin-4 (IL-4). To elucidate whether PTHrP produced by ATL cells is regulated by IL-2 or IL-4, we investigated the in vitro effects of IL-2 and IL-4 on the release of PTHrP. IL-2 increased the release of PTHrP into the conditioned medium from leukemic cells in some, but not all, ATL patients; however, IL-4 did not affect the PTHrP release. PTHrP messenger RNA (mRNA) levels were increased in ATL cells cultured in the presence of IL-2. These data suggest that IL-2 plays a role in the regulation of hypercalcemia by enhancing the production of PTHrP in ATL patients.

Aged↗
PubMed1993

An HTLV-I carrier who developed CD4+ T-CLL expressed the IL-2 receptor beta chain alone without expressing the alpha chain.

We describe a case of T-chronic lymphocytic leukaemia (T-CLL) with monoclonal proliferation of CD3+4+8- T cell expressing the interleukin 2 receptor (IL-2R) beta chain without expressing the alpha chain. Southern blot analysis of T-cell receptor beta chain gene revealed rearranged bands. The serum antibody was positive against human T-cell lymphotropic virus type I (HTLV-1)-associated antigens, but monoclonal integration of proviral DNA was not detected in the leukaemic cells. In accordance with the expression of IL-2R beta chain, the leukaemic cells proliferated in response to exogenous IL-2 without prior stimulation. However, culture supernatants of these cells did not show IL-2 activity. Since the role of the IL-2R beta chain in freshly isolated cells from T-CLL patients is not well understood, detailed analysis of this case would give us valuable information on the role of IL-2/IL-2R system in the proliferation of the leukaemic T cells.

Aged↗
PubMed1993

Screening for thyroid diseases in an iodine sufficient area with sensitive thyrotrophin assays, and serum thyroid autoantibody and urinary iodide determinations.

OBJECTIVE: The present study was designed to investigate the prevalence of thyroid dysfunction and its relation to thyroid autoantibodies and urine iodide concentration in apparently healthy people residing in Sapporo, a city of northern Japan, where the iodine intake is high. DESIGN AND SUBJECTS: Serum TSH and thyroid autoantibodies, and urine iodide were measured in 4110 people (2931 men and 1179 women) (age 45.6 +/- 10.3 years (mean +/- SD)) who were recruited at the hospital for medical examinations. RESULTS: The thyroid autoantibodies were positive in 6.4% of males and 13.8% of females with an age-related increase. Of the people with positive antibodies, 87.2% had normal TSH values (0.15-5.0 mU/l) as measured by a sensitive assay. The prevalence of unsuspected hyperthyroidism as defined by suppressed TSH values was 0.61%, of which 64% was diagnosed as Graves' disease based on positive thyrotrophin receptor antibody results. The prevalence of unsuspected hypothyroidism, as evidenced by supranormal TSH, was 0.68% for males and 3.13% for females with an age-related increase. Of those with hypothyroidism, 45.5% were autoantibody positive. The overall prevalence of Hashimoto's thyroiditis was 13.11% for females and 6.15% for males. The urine iodide levels of hypothyroidism with a positive autoantibody of 38.5 (17.7-83.9) mumol/l and a negative autoantibody of 34.9 (17.9-67.9) mumol/l were both significantly higher than that of normal subjects (26.9 (14.6-49.6) mumol/l) (P < 0.01). When iodine intake was restricted for 6-8 weeks for hypothyroid subjects, the elevated TSH and thyroglobulin and low free T4 levels were reversed in the autoantibody negative but not in the positive group. CONCLUSIONS: This study provides further information on the prevalence of thyroid dysfunction and autoimmune thyroid diseases in an iodine sufficient area. In addition, it suggests that more than half of the patients with unsuspected hypothyroidism were negative for autoantibodies and that the excessive iodine intake may be involved in causing latent hypothyroidism.

Adult↗