Arrhythmias induced by pulsed magnetic fields.
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Animals↗
Biomedical subjects
T Kawakami
Publications and source records attributed to T Kawakami.
Tyrosine phosphorylation of MB-1, B29, and HS1 proteins in human B cells following receptor crosslinking.
Recent studies of murine and human B lymphocytes have shown that crosslinking of surface IgM (sIgM) and sIgD stimulates tyrosine phosphorylation of a set of proteins involved in signal transduction. We investigated tyrosine phosphorylation of the sIg-associated proteins MB-1 and B29, and p75HS1 (HS1), and the association of HS1 with MB-1/B29 heterodimers in normal human B cells and a human B lymphoma cell line, B104. Using immunoprecipitation with anti-phosphotyrosine antibodies (Abs) followed by immunoblotting with anti-MB-1 Abs, anti-B29 Abs or anti-HS1 Abs, we demonstrated that MB-1, B29 and HS1 were tyrosine-phosphorylated after sIgM or sIgD crosslinking. Immunoprecipitation with anti-B29 Abs followed by anti-HS1 Abs immunoblotting revealed that HS1 was associated with MB-1/B29 heterodimers after sIgM or sIgD crosslinking. The results showed that HS1 may play an important role in signal transduction through sIgM and sIgD on human B cells.
Adaptor Proteins, Signal Transducing↗
Effects of strong pulsed magnetic fields on the cardiac activity of an open chest dog.
The heart of an open chest dog was stimulated by strong magnetic fields which were damped sinusoidal pulses with the one-cycle period of 1.47 ms. Stimulation effects were detected by electrocardiograph (ECG) and arterial blood pressure as a function of the strength of the field, the triggering point in the cardiac cycle, and the position of a stimulating coil. The threshold for arrhythmias was a minimum for the stimuli triggered at the apex of the T wave and on the P wave in the ECG. Premature ventricular and premature atrial contractions occurred according to whether the coil was placed over the ventricles or the atria. Ventricular defibrillation can not be attained by the magnetic stimulus with the flux density of 9.2 T which was the maximum field used.
Animals↗
Neodymium:YAG laser ablation of the prostate gland--acute perioperative morbidity and short-term outcome.
Twenty-three patients with symptomatic bladder outlet obstruction due to benign prostatic hyperplasia were successfully treated with laser prostatectomy using the Urolase right-angle firing neodymium: Yttrium Aluminum Garnet laser fiber. Most of the patients had health problems of moderate severity. Their conditions were compared preoperatively and 3 mo postoperatively. Symptom scores decreased from an average of 23.9 to 7.0. Symptomatic relief was achieved in 95.7% of patients. Peak urinary flow rates increased from an average of 6.4 to 17.0 ml/s. The residual urine decreased from an average of 45.2 to 22.9 ml. The volume of the prostate gland measured by sonography decreased from an average of 32.8 to 25.7 ml. Virtually no blood loss was noted intraoperatively. Acute urinary retention occurred immediately following removal of the catheter in 3 out of 17 (17.6%) patients without a percutaneous cystostomy tube. Acute epididymitis developed in 5 out of 20 (25.0%) patients without bilateral vasectomy. Based on these results, laser prostatectomy may be concluded to be a safe and effective alternative to standard transurethral resection of the prostate gland, particularly in the case of high-risk patients.
Adenocarcinoma↗
Tyrosine phosphorylation and activation of Bruton tyrosine kinase upon Fc epsilon RI cross-linking.
Tyrosine phosphorylation of several cellular proteins is one of the earliest signaling events induced by cross-linking of the high-affinity receptor for immunoglobulin E (Fc epsilon RI) on mast cells or basophils. Tyrosine kinases activated during this process include the Src family kinases, Lyn, c-Yes, and c-Src, and members of another subfamily, Syk and PTK72 (identical or highly related to Syk). Recently, some of us described two novel tyrosine kinases, Emb and Emt, whose expression was limited to subsets of hematopoietic cells, including mast cells. Emb turned out to be identical to Btk, a gene product defective in human X-linked agammaglobulinemia and in X-linked immunodeficient (xid) mice. Here we report that Fc epsilon RI cross-linking induced rapid phosphorylation on tyrosine, serine, and threonine residues and activation of Btk in mouse bone marrow-derived mast cells. A small fraction of Btk translocated from the cytosol to the membrane compartment following receptor cross-linking. Tyrosine phosphorylation of Btk was not induced by either a Ca2+ ionophore (A23187), phorbol 12-myristate 13-acetate, or a combination of the two reagents. Co-immunoprecipitation between Btk and receptor subunit beta or gamma was not detected. The data collectively suggest that Btk is not associated with Fc epsilon but that its activation takes place prior to protein kinase C activation and plays a novel role in the Fc epsilon RI signaling pathway.
Agammaglobulinaemia Tyrosine Kinase↗
EFFECT OF MECHANICAL VIBRATION ON ACTIVE TENSION IN THE LONGITUDINAL RETRACTOR MUSCLE OF A SEA CUCUMBER STICHOPUS JAPONICUS
1. The effect of mechanical vibration on active tension in an echinoderm somatic smooth muscle was studied using the longitudinal retractor muscle (LRM) of a sea cucumber Stichopus japonicus. 2. The steady contracture tension in LRM fibres maximally activated with 10(-3) mol l-1 acetylcholine (ACh) was reduced by vibrations (peak-to-peak amplitude, 0.5­2.5 % of l0, where l0 is the slack length of the muscle; frequency, 5­100 Hz). The extent of reduction of active contracture tension increased with increasing amplitude of vibration, but it did not change appreciably with increasing frequency of vibration. 3. The steady contracture tension in LRM fibres submaximally activated with 10(-5) mol l-1 ACh was more markedly reduced by vibrations than was that in maximally activated fibres. 4. The vibration-induced reduction of active contracture tension disappeared when temperature was lowered from 20­23 to 0 °C. 5. The development of contracture tension in LRM fibres activated with ACh was not affected by mechanical vibration. 6. These results are discussed in connection with the vibration-induced decrease in the rate of breakage of the actin­myosin linkages responsible for isometric force generation.
Journal Article↗
Distribution of substance P-containing and catecholaminergic nerve fibers in the rabbit carotid body: an immunohistochemical study in combination with catecholamine fluorescent histochemistry.
The distribution of substance P (SP)-immunoreactive nerve fibers in the rabbit carotid body was studied in combination with catecholamine autofluorescence images of sections where SP immunoreactivity was confirmed. Immunoreactivity for SP was found in nerve fibers distributed in the parenchyma of the carotid body. No glomus cells with SP immunoreactivity were observed in the carotid body. On comparing the distribution of SP-immunoreactive fibers with the catecholamine autofluorescence image in a single section, most SP fibers appeared associated with the fluorescent glomus cells, and were located around clusters of them. These results support the suggestion that SP fibers in the cat and rat carotid bodies are involved in chemosensory mechanisms. Furthermore, a survey of the present results and previous ones reported by other workers indicates that SP may be an essential neuropeptide in chemoreceptor organs in most vertebrates from amphibians on upwards evolutionally. In addition, the courses of some catecholaminergic fibers precisely agreed with those of some SP fibers. This suggests that certain sympathetic nerve fibers also contain SP.
Animals↗
[Comparison of tumor markers versus their relative values to prostatic volume in detecting prostate cancer].
Diagnostic utility of serum markers and their relative values to prostatic volume were evaluated using Receiver Operator Characteristics Analysis (ROC analysis) in 173 patients who underwent ultrasound guided biopsy of the prostate gland. Seventy cases (40.5%) of prostate cancer were detected. As a whole, prostate specific antigen density (PSAD) and prostate specific antigen (PSA) were more useful than gammaseminoprotein density (GSMD), gammaseminoprotein (GSM) and prostatic acid phosphatase in diagnosing cancer judged by the area under the ROC curve denoting a test's diagnostic accuracy (p < 0.05). No significant difference was noted, however, between PSAD and PSA (p > 0.05). Prostate specific antigen density was more predictive for prostate cancer than PSA in a subgroup of patients with PSA levels of 2.0-10.0 ng/ml (p < 0.05). No advantage of PSAD was obtained in patients with intermediate PSA levels of 2.0-5.0 ng/ml or benign-feeling glands (p > 0.05). Higher sensitivity could be achieved by using Eiken PSA 2.0 ng/ml as a cutoff rather than the recommended value of 3.0 ng/ml. This helped to diagnose 5 more cases of prostate cancer who otherwise might have been missed if PSA cutoff of 3.0 ng/ml had been used. A PSAD cutoff of 0.15 has a sensitivity of 81.4%, a specificity of 87.4% and an accuracy of 85.0%. However, use of this cutoff for biopsy could result in unacceptable numbers of undiagnosed cases, including many potentially curable cancers. Though PSAD may enhance sensitivity and specificity in a certain group of patients, this gain is not sufficient to reliably define the group at highest risk of prostate cancer. Indication of biopsy should still be determined based upon PSA concentration rather than PSAD value.
Adult↗
[Usefulness and limitation of digital rectal examination and imaging studies in staging prostate cancer].
The diagnostic usefulness of digital rectal examination (DRE), transrectal ultrasonography (TRUS), magnetic resonance imaging (MRI) and computed tomography (CT) was compared in the differentiation of stage B from stage C prostate cancer. Eighteen patients who had undergone radical retropubic prostatectomy were included in this study. Overall, the positive predictive values (PPV) for detecting extraprostatic disease (extracapsular extension, seminal vesicle invasion) were 100% for DRE, 88.9% for TRUS and 80.0% for MRI, respectively. Corresponding figures for accuracy in detecting extraprostatic spread were 55.6%, 66.7% and 61.1%, respectively. The PPV and accuracy for detecting extraprostatic disease in 13 patients with localized cancer (< stage B) were 75.0%, 53.8% for TRUS and 66.7%, 53.8% for MRI, respectively. Both of these examinations appeared to be superior to DRE alone. The PPV and accuracy increased when findings on TRUS and MRI coincided. Computed tomography was less accurate than MRI in diagnosing nodal involvement because of the higher incidence of false positives. Further efforts should be focused on enhancing preoperative diagnostic precision in staging prostate cancer because of the limited usefulness of the current imaging techniques. Development of more reliable diagnostic modalities or designing ideal combination of these studies are desperately needed.
Aged↗
[The effects of continuous interpleural vs. epidural infusion for postoperative pain relief following thoracotomy].
We studied whether continuous interpleural infusion of bupivacaine would be effective in alleviating pain after thoracotomy compared with effect of continuous epidural infusion of bupivacaine and buprenorphine. Twenty patients who had received thoracotomy and lobectomy were randomly divided into two groups to receive continuous interpleural infusion (IP group) of 0.5% bupivacaine at the rate of 5 ml.h-1 or continuous epidural infusion (E group) of 0.25% bupivacaine and 0.025 buprenorphine at the rate of 1 ml.h-1. The patients assessed their level of pain using a 100 mm visual analog scale (VAS) at rest and on coughing or changing the posture, verbal descriptor pain scale (VDPS), and times of supplemental analgesic. Assessment was performed at 7 points (mornings and evenings) for 3 postoperative days. In the evening of the day of surgery, VAS at rest in IP group was significantly higher than one in E group, but VASs at rest were similar in both groups from the first postoperative day to the third postoperative day. VAS on coughing or changing the posture in IP group was significantly higher than in E group in the evening of the day of surgery, and VASs on coughing or changing the posture in IP group were higher than in E group for 3 postoperative days. Supplemental analgesics were administered significantly more often than in E group in the evening of the first postoperative day. We conclude that continuous interpleural infusion does not give better analgesia than continuous epidural infusion after thoracotomy.
Adult↗
[To establish confidential relationship between physician and patient: how should be in future?].
Nearly 10 years have passed since I was hospitalized for two months to have a surgery of the Ano-Rectum. Meantime, suffering from severe physical pain at the early postoperative days followed by various anxieties throughout the time of hospitalization, I could see and learn that daily warm talks and kind behaviors of the nurses and doctors in charge were very impressive. The doctor's adequate and precise explanation on the disease and surgical procedure to be selected was quite understandable and also agreeable for me. Then, I could have a firm confidence in all treatments of the doctor. Fortunately, I could return to the routine work as a surgeon without much difficulties after surgery. Recently, I have been appointed as the director of the hospital which is now under replacement to improve the system and design of the ward. In this chance, I am doing my best to modify the system and design as much as possible by considering and reflecting all needs and desires of the patients, some of which are originated from my own experiences as a patient 10 years ago.
Confidentiality↗
Two cases of mandibular radicular cysts with ciliated epithelium: an electron microscopic study.
We studied two cases of mandibular radicular cysts lined in part with ciliated epithelium by examining them histopathologically and ultrastructurally. In addition, we examined the incidence of cilia in 205 radicular cysts in the biopsy materials collection in our Department. No other mandibular cysts having cilia in the lining were found, and so these were very rare. Regarding the histogenesis of the cilia, we consider that the development of cilia in mandibular radicular cysts may be due to true metaplasia rather than to adaptation which is a functional requisite of the lining epithelium for the unique cystic environment.
Adult↗
[Examination of the degree of agreement among dental findings used for personal identification (Part 4)--Lapse of time between features of dentition at time of death and those in the last dental record].
In cases of personal identification of corpses, there is usually a lapse of several years between the features of dentition at the time of death and the features documented in the last dental records. We therefore investigated the degree of agreement of the dental findings in the same subject under these circumstances. For the study, 6,000 records of dental examinations carried out between grades 1-6 for 1,000 dental students in their 20's (740 males and 260 females) were examined. These documents were then divided according to the number of years that had elapsed from 1 to 5 years, and were collated. In this investigation, the former dental features on certain grade student were regarded as antemortem data, and the latter dental features elapsing several years were regarded as the postmortem data. The total number of records collated was 15,000. The records were classified according to four criteria: (1) intact teeth (non-carious and non-treated), (2) carious teeth (C1-C4), (3) treated teeth (crown, inlay etc.), and (4) missing teeth (including pontic and denture). The results obtained were as follows: 1. Correlation between number of corresponding teeth and lapse of time: When the number of corresponding teeth was 28-26, the frequency of tooth agreement in the same subject declined with time. When 24 teeth or less were present, the frequency increased. 2. Correlation between changes in dental findings and tooth regions in the same subject: The anterior teeth tended to remain intact, the first premolars changed from intact to missing, and second premolars changed from intact to treated. The dental findings for the first molars tended to change from treated to treated and missing. The second molars showed diverse changes. 3. Correlation between lapse of time and patterns of change in the dental findings: There was a tendency for cases showing the same states of dentition to become fewer, and for cases showing changes from intact and carious to treated and missing teeth to become more frequent, excluding the mandibular anterior teeth. 4. Correlation between tooth regions and frequency of inconsistent changes in dental findings: A change from treated to intact was frequently observed in maxillary incisors (3.1-3.2%) and second molars (2.5%), and a change from treated to carious was also observed in the mandibular molars (2.2-2.3%). Inconsistent changes in the mandibular anterior teeth were seldom observed.
Adult↗
[Urinary extravasation: report of five cases and review of the Japanese literature].
We studied the etiology, diagnosis and management of 201 cases of urinary extravasation reported in the Japanese literature along with our five cases. Most of them were caused by urolithiasis and malignant tumors. Four of our five cases also presented with a ureter stone; two being cured by spontaneous stone passage within several days and the others being treated by ureterolithotomy or nephrectomy. The other case involving a ureter tumor was treated by nephroureterectomy with partial cystectomy. The clinical manifestations of urinary extravasation were distinguished as spontaneous peripelvic extravasation and spontaneous rupture of the renal pelvis and ureter. Performing an accurate and differential diagnosis of these cases, however, was difficult. We therefore propose a set of clinical diagnostic criteria based on our findings of X-ray examination and the macroscopic appearance seen during surgical treatment. We review the 201 reported cases along with our five cases of urinary extravasation and discuss their diagnostic procedures and treatment approaches.
Adult↗
Cloning of the dihydroxyacid dehydratase-encoding gene (ILV3) from Saccharomyces cerevisiae.
The biosynthesis of branched-chain amino acids (aa) involves three shared pathways through which pyruvate or alpha-ketobutyrate are converted into alpha-keto acids, precursors of valine, leucine or isoleucine. In eukaryotes, few of these common enzymes have been purified to homogeneity, and the whole complement of biosynthetic genes has not been cloned from a single species. In yeasts, most of these genes (ILV genes) have been cloned and sequenced, with the exception of that coding for dihydroxyacid dehydratase (DAD, EC 4.2.1.9), the third enzyme in the common pathways. We have isolated Saccharomyces cerevisiae genomic sequences by hybridization to an oligodeoxyribonucleotide (oligo) probe designed from a highly conserved domain among bacterial DAD-encoding genes. The cloned sequences have been located to S. cerevisiae chromosome X, mapped within 0.4 centiMorgans (cM) of the ilv3 locus, and found to complement the ilv3 mutations of various yeast strains. Nucleotide (nt) and aa sequence analyses of the longest open reading frame (ORF) located within the cloned sequences identified them as the ILV3 gene, which codes for the yeast DAD. With our cloning of ILV3, yeast becomes the only eukaryotic system from which all ILV genes have been cloned, thus allowing direct molecular analyses of their regulation.
Amino Acid Sequence↗
Targeted disruption of IRF-1 or IRF-2 results in abnormal type I IFN gene induction and aberrant lymphocyte development.
Interferon regulatory factor 1 (IRF-1), a transcriptional activator, and its antagonistic repressor, IRF-2, were originally identified as regulators of the type I interferon (IFN) system. We have generated mice deficient in either IRF-1 or IRF-2 by gene targeting in embryonic stem cells. IRF-1-deficient fibroblasts lacked the normally observed type I IFN induction by poly(I):poly(C), while they induced type I IFN to similar levels as the wild type following Newcastle disease virus (NDV) infection. In contrast, IRF-2-deficient fibroblasts showed up-regulated type I IFN induction by NDV infection. A profound reduction of TCR alpha beta+CD4-CD8+ T cells in IRF-1-deficient mice, with a thymocyte developmental defect, reveals a critical role for IRF-1 in T cell development. IRF-2-deficient mice exhibited bone marrow suppression of hematopoiesis and B lymphopoiesis and mortality following lymphocytic choriomeningitis virus infection.
Animals↗
Immunohistochemical coexistence of calcitonin gene-related peptide and substance P in the nerve fibers of the internal gills of bullfrog (Rana catesbeiana) larvae.
A double-labelling immunofluorescence study of the internal gills of larval bullfrogs revealed coexistence of calcitonin gene-related peptide (CGRP) and substance P (SP) in the same nerve fibers in the gill tufts. More than about 95% of CGRP fibers showed coexistence of SP, although some fibers contained CGRP without SP. In the branchial muscle, all CGRP fibers demonstrated coexistence of SP. These findings suggest that both CGRP- and SP-containing fibers may use both peptides as neuromodulators of active ion transport and gill movements.
Animals↗
Structure and expression of novel protein-tyrosine kinases, Emb and Emt, in hematopoietic cells.
Two novel tyrosine kinase cDNAs were obtained from murine mast cells. These kinases, Emb and Emt, constitute a novel tyrosine kinase subfamily which may also include Tec, a kinase preferentially expressed in liver, and Dsrc28, a fruit fly kinase. Both lack hydrophobic stretches characteristic of the transmembrane domains found in growth factor receptor tyrosine kinases and carboxyl-terminal, negative regulatory tyrosine residue found in Src family kinases. In addition to the Src homology region 2 (SH2) and SH3 domains characteristic of the Src family kinases and other signaling molecules, Emb and Emt share a similar amino-terminal domain comprised mainly of two repeat segments. The emb 2.7-kb transcript was expressed in mast cells, myeloid cells and B lymphocytes while the emt 4.6-kb mRNA in mast cells, myeloid cells and T lymphocytes. The evidence for in vitro tyrosine kinase activity of Emb and Emt proteins is also provided.
Amino Acid Sequence↗