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Biomedical subjects

H Nishida

Publications and source records attributed to H Nishida.

At least 127 records · Page 7Linked to original sources

A prokaryotic gene cluster involved in synthesis of lysine through the amino adipate pathway: a key to the evolution of amino acid biosynthesis.

In previous studies we determined the nucleotide sequence of the gene cluster containing lys20, hacA (lys4A), hacB (lys4B), orfE, orfF, rimK, argC, and argB of Thermus thermophilus, an extremely thermophilic bacterium. In this study, we characterized the role of each gene in the cluster by gene disruption and examined auxotrophy in the disruptants. All disruptants except for the orfE disruption showed a lysine auxotrophic phenotype. This was surprising because this cluster consists of genes coding for unrelated proteins based on their names, which had been tentatively designated by homology analysis. Although the newly found pathway contains alpha-aminoadipic acid as a lysine biosynthetic intermediate, this pathway is not the same as the eukaryotic one. When each of the gene products was phylogenetically analyzed, we found that genes evolutionarily-related to the lysine biosynthetic genes in T. thermophilus were all present in a hyperthermophilic and anaerobic archaeon, Pyrococcus horikoshii, and formed a gene cluster in a manner similar to that in T. thermophilus. Furthermore, this gene cluster was analogous in part to the present leucine and arginine biosyntheses pathways. This lysine biosynthesis cluster is assumed to be one of the origins of lysine biosynthesis and could therefore become a key to the evolution of amino acid biosynthesis.

2-Aminoadipic Acid↗

Perinatal and infant outcome of pregnant patients undergoing chronic hemodialysis.

Recently, perinatal outcome in patients undergoing chronic hemodialysis has been improved. But the conditions that will most likely result in successful pregnancy are still obscure. We retrospectively analyzed 15 pregnant patients who were undergoing chronic hemodialysis before pregnancy treated in our perinatal center. We divided these 15 cases into 2 groups: one group of 11 patients whose infants survived and the other group of 4 patients whose infants died 6 h to 8 months after birth due to prematurity. The rate of successful pregnancies having a surviving infant was 73.3% (11/15). We compared the maternal conditions and the progress of pregnancy in the 2 groups. Significant differences (p<0.01) were seen as follows. The patients in the group whose infants survived underwent hemodialysis for a shorter term before pregnancy (1-6 years), most of them (9/11) could produce urine (> or =50 ml/day), and the period of gestation was extended (33.3+/-4.7 weeks), so the infants were heavier (1,782.9+/-678.3 g). All the patients who underwent more than 9 years of hemodialysis could not have a surviving infant. From this we can assume that the shorter the period of dialysis before pregnancy, the better the condition is that is likely to result in women giving birth and the better is their infant's chance of survival.

Adult↗

Pre-surgical localization of ectopic parathyroid glands using three-dimensional CT imaging, 99Tcm sestamibi, and 99Tcm tetrofosmin imaging.

We describe two patients with ectopic parathyroid glands evaluated with 99Tcm sestamibi, 99Tcm tetrofosmin, and three-dimensional computed tomography (3D-CT). Radionuclide images of the neck were acquired at 10 min, and at 2-3 h after radiopharmaceutical injection, and showed intense uptake in the ectopic parathyroid tissue. These patients also underwent contrast enhanced CT imaging with 3D reconstructions which were evaluated for ability to visualize critical anatomical structures, e.g. blood vessels and parathyroid glands. Based on 3D-CT images, surgical planning was altered in one of the two patients studied. In conclusion, reconstructed 3D-CT images provided useful anatomical localization of ectopic parathyroid glands identified on 99Tcm sestamibi and 99Tcm tetrofosmin imaging. This anatomical information aided surgical planning of gland resection.

Choristoma↗

Mouse popliteal lymph node assay for assessment of allergic and autoimmunity-inducing potentials of low-molecular-weight drugs.

In the present collaborative study, popliteal lymph node (PLN) responses to penicillin G (an allergenic chemical), D-penicillamine (an autoimmunity-inducing chemical), and barbital (a negative reference chemical) were investigated in three different mouse strains by ten pharmaceutical companies. Two inbred mouse strains (BALB/c and A/J) and one outbred strain (ICR) were subcutaneously injected with saline solutions containing penicillin G (1.25, 2.5 and 5 mg/mouse), D-penicillamine (0.5, 1 and 2 mg/mouse), or barbital (2 mg/mouse) into one hind footpad and saline only was injected into the contralateral footpad. PLN cellularity indices were determined on day 7. In the three strains tested, the penicillin G and D-penicillamine injections resulted in approximately dose-dependent responses. In contrast, barbital failed to generate a significant PLN reaction. In the typical data from one of the participating laboratories, the PLN responses of A/J, BALB/c, and ICR to penicillin G were high, intermediate and low, respectively, while their PLN responses to D-penicillamine were all high. Some variation in PLN cellularity indices was observed among the participating laboratories, but reproducibility of the popliteal lymph node assay (PLNA) evaluation was partly confirmed. Although the appropriate selection of mouse strains and drug dosage levels has to be considered, these results suggest that the PLNA may be an appropriate screening system for prediction of the allergic or autoimmunity-inducing potentials of low-molecular-weight drugs.

Allergens↗

CD36 mediates long-chain fatty acid transport in human myocardium: complete myocardial accumulation defect of radiolabeled long-chain fatty acid analog in subjects with CD36 deficiency.

Long-chain fatty acids (LCFA) are the major energy substrate for heart and their oxidation is important for achieving maximal cardiac work. However, the mechanism of uptake of LCFA by myocardium has not been clarified. We previously reported that bovine myocardial LCFA transporter has a sequence homology to human CD36. Clinically, total defect of myocardial uptake of radiolabeled long-chain fatty acid analog [123I-BMIPP: Iodine-123 15-(p-iodophenyl)-(R,S)-methylpentadecanoic acid] has been reported in some restricted cases, but the etiology has not been clarified. In the present study, we analyzed CD36 expression and CD36 gene in subjects who showed total lack of myocardial 123I-BMIPP accumulation, and, vice versa, evaluated myocardial 123I-BMIPP uptake in subjects with CD36 deficiency. Four unrelated subjects were evaluated, Two were found to have negative myocardial LCFA accumulation by 123I-BMIPP scintigraphy, after which the expression of CD36 on their platelets and monocytes was analyzed. Remaining two subjects were identified as CD36 deficiency by screening, then 123I-BMIPP scintigraphy was performed. Expression of CD36 on platelets and monocytes was measured by flow cytometric analysis. The molecular defects responsible for CD36 deficiency was detected by allele-specific restriction enzyme analysis. CD36 expression was totally deficient in all 4 subjects on both platelets and monocytes. Two subjects were homozygous for a 478C-->T mutation. One was heterozygous for the dinucleotide deletion of exon V and single nucleotide insertion of exon X, and remaining one was considered to be heterozygous for the dinucleotide deletion of exon V and an unknown gene abnormality. All cases demonstrated a completely negative accumulation of myocardial LCFA despite of normal myocardial perfusion, which was evaluated by thallium scintigraphy. In addition, all cases demonstrated apparently normal hepatic LCFA accumulation Thus, these findings suggested that CD36 acts as a major myocardial specific LCFA transporter in humans.

Aged↗

[A case of primary Sjögren's syndrome presenting with aseptic meningoencephalitis associated with sarcoidosis].

A 64-year-old Japanese woman with sarcoidosis and primary Sjögren's syndrome was admitted to our hospital in January 1998 for consciousness loss. Physical examination revealed meningeal signs and hyperreflexia in the lower limbs. Laboratory investigations showed hypergammaglobulinemia and high titers of autoantibodies such as RF, ANA, anti SS-A and SS-B antibody. In addition, she had keratoconjunctivitis, and an apple-tree pattern was observed in sialography, but serum ACE was normal. In the cerebrospinal fluid (CSF), the cell count, total protein, and interleukin 6 (IL-6) were increased, but ACE in CSF was normal. We diagnosed the case as primary Sjögren's syndrome presenting with aseptic meningoencephalitis. After treatment with prednisolone, her manifestations and CSF findings including IL-6 resolved. Therefore, the level of IL-6 in CSF may be an indicator for the activity of primary Sjögren's syndrome associated with central nervous manifestations.

Agammaglobulinemia↗

[A case report of a coronary fistula from left coronary artery to left ventricle].

The patient is a 44-year-old man. He has had chest pain on effort since 1994, diagnosed as unstable angina in 1996. He was found to have three vessel disease on coronary angiography and was sent to TWMC for operation. CABG was performed for the right and left anterior descending arteries, and TMLR for the posteroinferior region because the left circumflex artery was fine and ungraftable. Both the grafts were patent and there was improved LV function. Interestingly, we found a coronary fistula running from the left coronary artery to the left ventricle. As far as we can tell from our literature searches, this is the first time that a coronary fistula has been found after TMLR.

Adult↗

[Complete arterial revascularization in emergency CABG].

Between August 1987 and November 1998, 137 patients underwent emergency CABG within 24 hours from the notification of cardiologist. Among them, 37 patients (27%) (34 men, 3 women) with a mean age of 59.9 (range, 39-76) underwent multiple CABG with exclusive use of arterial conduits. Preoperative diagnosis was acute myocardial infarction in 20 patients and unstable angina in 17 patients. Twenty-nine patients (78%) had either triple vessel or left main disease. There were 3 redo CABG and 3 patients were on hemodialysis. Postoperative follow-up averaged 44 months. Twenty-nine patients (78%) were under IABP support preoperatively. The mean number of anastomoses was 2.65 (range, 2-5). One patient (2.7%) died of persistent heart failure 54 days postoperatively. The patency was confirmed angiographically in 33 patients 3-4 weeks after surgery. Overall patency was 90.6% (LITA: 93.0%, RGEA: 76.2%, RITA, radial: 100%). There were no late deaths or redo CABG, and 2 patients sustained myocardial infarction and 3 patients underwent PTCA during follow-up. Five-year actuarial survival rate was 97.1% and cardiac event-free rate was 75.7%. These excellent early and long-term results suggest that complete arterial grafting for emergency CABG should be considered as a primary treatment in patients who have multivessel or left main disease, and no ongoing profound cardiogenic shock or rapid deterioration.

Adult↗

New graft holder for coronary artery bypass using arterial conduits.

An arterial graft holder was designed to facilitate coronary artery bypass surgery. It can be used to open the heel of arterial conduits and it immobilizes the graft with a spring clamp. The tip of the holder is made from flexible, silicon-coated vinyl chloride tubing, so that it can be inserted into the arterial lumen without causing endothelial injury.

Anastomosis, Surgical↗

Two new drainage tubes for minimally invasive cardiac surgery.

BACKGROUND: The limited exposure typical of new minimally invasive surgical approaches to cardiac surgery makes it difficult to utilize traditional equipment such as temporary pacing electrodes or the placement of drainage tubes into the lateral pleural space. To overcome these difficulties, we have developed specialized drainage tubes just for limited access cardiac surgery. METHODS: The first device is a drainage tube with temporary pacing function. It has three fixed electrodes and one free pacing wire incorporated into an elliptical, angled 28 Fr silicone drainage tube. This tube is placed in the space between the heart and the diaphragm. The two fixed electrodes provide epicardial contact for ventricular pacing. The third fixed electrode and one free pacing wire are for the purpose of atrial pacing (Japanese patent #2,701,135). The second device is a Y-shaped drainage tube. Frequently, the pleural space is opened during harvesting of an internal mammary graft and then insertion of a chest tube in the thoracic cavity becomes necessary. We developed a new Y-shaped tube where one segment is placed in the retrosternal space and one segment is placed in the pleural cavity. (Japanese Association of Intellectual Copyright #130,591) RESULTS: The drainage-pacing device was used in 48 coronary artery bypass grafting (CABG) patients. Drainage function and pacing function were excellent in all patients. The bifurcated drainage device was used in 34 patients achieving effective drainage of both cavities without complication during or after removal. CONCLUSIONS: Due to the limited surgical exposure provided by the newer minimally invasive procedures in cardiac surgery, specialized equipment that can be inserted through small incisions needs to be developed. We report the development of a new drainage-pacing device as well as a bifurcated drain for simultaneous drainage of the mediastinal and pleural cavities. These devices have facilitated minimally invasive cases and were free of complications.

Coronary Artery Bypass↗

Induction of synaptosomal-associated protein-23 kD (SNAP-23) by various cytokines.

Cytokines manifest their function through regulation of gene expression. We searched for immediate-early cytokine responsive genes by the mRNA differential display technique using interleukin-3 (IL-3)-dependent OTT-1 cells, and have isolated a novel cDNA which encodes 210 amino acids and shows 87% amino acid identity to human SNAP-23 (synaptosomal-associated protein of 23 kD). The message for this protein (mouse SNAP-23) was induced in OTT-1 cells by IL-3, granulocyte-macrophage colony-stimulating factor (GM-CSF), and IL-5. The experiment using C-terminal deletion mutants of the common beta subunit (betac) of IL-3/GM-CSF/IL-5 receptors showed that expression of SNAP-23 was associated with the Ras-Raf-MAPK pathway, but not with the JAK-STAT pathway. Moreover, SNAP-23 was induced in response to a wide variety of cytokines, including IL-2, IL-3, IL-5, IL-10, stem cell factor, G-CSF, GM-CSF, leukemia inhibitory factor, and erythropoietin. Constitutive expression of SNAP-23 was seen in various tissues, including heart, lung, kidney, liver, spleen, and small intestine. Possible involvement of SNAP-23 in cytokine signal transduction is discussed.

Amino Acid Sequence↗

Maternal and zygotic expression of the endoderm-specific alkaline phosphatase gene in embryos of the ascidian, Halocynthia roretzi.

Alkaline phosphatase (AP) activity is expressed by endodermal cells of ascidian larvae. It was reported previously that the expression of AP activity is resistant to treatment with actinomycin D, a transcription inhibitor that inhibits the appearance of several other tissue-specific molecules and morphological markers of tissue formation in developing ascidians. The resistance of AP expression to actinomycin D treatment suggests that endodermal AP activity does not depend on zygotic transcription and that its appearance is mediated by the translational activation of maternal AP mRNA present in ascidian eggs. However, it was also shown that anucleate merogons do not develop AP activity. To directly examine whether maternal AP transcripts are present in the cytoplasm of eggs, we isolated a cDNA of an endoderm-specific AP in Halocynthia roretzi and examined the temporal and spatial expressions of this gene during embryogenesis using Northern blots and in situ hybridization. Maternal AP transcripts were detected in oocytes, cleaving-stage embryos, and in gastrulae, and endoderm-specific AP transcripts dramatically increased about 14 times from the neurula stage to the larval stage in endoderm precursor cells. These results suggest that the differentiation of endoderm is primarily correlated with the activation of zygotic transcription of the AP gene, presumably by egg cytoplasmic factors, similar to how muscle and epidermis are believed to develop.

Alkaline Phosphatase↗

Exanthematous disease induced by toxic shock syndrome toxin 1 in the early neonatal period.

BACKGROUND: We have seen a number of patients who developed systemic exanthema and thrombocytopenia in the first week of life. Although nearly 100% of the patients were carriers of meticillin-resistant Staphylococcus aureus (MRSA), no clear link between MRSA and this exanthematous disease has yet been made. METHODS: 20 neonates with exanthema and thrombocytopenia were selected for study. To see whether superantigenic exotoxins from MRSA are involved in the pathogensis of the exanthematous disease, we studied the production of these exotoxins by MRSA isolates from the neonates. We studied the expression of T-cell-receptor Vbeta and CD45RO in T cells taken from four of the neonates. We also analysed the DNA sequences of 16 cloned Vbeta2-positive T-cell-receptor-chain genes taken from two of the neonates. FINDINGS: Although most of the patients recovered within 5 days of onset of the exanthematous disease without any active treatment, two preterm infants died in the recovery phase. All patients showed colonisation by MRSA. The MRSA produced toxic shock syndrome toxin-1 (TSST-1). The number of T cells positive for T-cell-receptor Vbeta2, reactive to TSST-1, was increased in the four patients studied (p<0.0001), and these T cells expressed CD45RO (p=0.0185). None of the Vbeta2 clones had the same junctional sequences. INTERPRETATION: The polyclonal expansion of Vbeta2-positive T cells in patients colonised by TSST-1-producing MRSA suggests that the pathogenic micro-organism of this neonatal exanthematous disease is S aureus, mainly MRSA, and that in its pathogenesis it activates T cells by TSST-1. Although the pathogenesis of both this exanthematous disease and toxic shock syndrome are fundamentally the same, a diagnosis of toxic shock syndrome cannot be made in this case, based on the clinical criteria for toxic shock syndrome. We propose neonatal toxic-shock-syndrome-like exanthematous disease (NTED) as the name for this disease.

Bacterial Toxins↗

[A case of coronary artery bypass grafting for effort angina in a patient with post skin grafting for an extramammary Paget's disease].

The extramammary Paget's disease of anogenital area is rare, and is seen as a precancerous lesion or carcinoma in situ. In most cases, surgical treatment including dissection of regional lymph nodes, skin resection and grafting should be considered first. A 74-year-old male suffered from effort angina and underwent triple coronary artery bypass grafting (CABG) including saphenous vein graft (SVG) harvested from right lower leg. Five years previously he underwent skin grafting for extramammary Paget's disease of both inguinal areas and the perineal area. The postoperative course was uneventful and he was discharged 23 days after the CABG operation. Extramammary Paget's disease is localized in epidermis for years and there has been no report of direct invasion into vessels. Therefore, there appears to be no reason not to use an SVG if there is no luminal thrombus or occlusion.

Aged↗

[Coronary artery bypass grafting for cases which were not amenable to preoperative left ventriculogram].

We evaluated the coronary artery bypass grafting (CABG) for the cases which were not amenable to preoperative left ventriculograms (LVG). Between June 1970 and March 1996, we had 2045 cases of isolated CABG, and 52 cases of which were not amenable to preoperative LVG. The reasons of no preoperative LVG were during cardiopulmonary resuscitation (CPR) in 4 cases, shock state in 14, NYHA class IV or CCS class IV in 26, angina attack after coronary angiography in 3 and so on. Preoperative diagnoses were acute myocardial infarction in 28, angina after infarction in 13, unstable angina in 9 and effort angina in 2. Preoperative conditions were reoperation in 6, insertion of intra-aortic balloon pumping in 46, chronic renal failure in 15 (hemodialysis in 4) and arrhythmia (VT or Vf) in 12. Concerning the coronary lesions, left main trunk and triple vessel diseases occupied 75% of all. Surgical deaths were 5 cases (9.6%) and hospital deaths were 4 cases (7.7%). The all cases which needed preoperative CPR were died with brain injury. The result of the cases which were not amenable to preoperative LVG were worse than the cases with ischemic cardiomyopathies. In conclusion, no preoperative LVG is one of the highest risk factors of all.

Adult↗

[Postoperative complications after coronary bypass operations in patients with pulmonary impairment].

The postoperative courses of 112 patients with pulmonary disease (59 with obstructive disease = Group 0, 38 with restrictive disease = Group R and 15 with mixed disease = Group M) who underwent elective coronary artery bypass grafting were retrospectively reviewed. Preoperative pulmonary function test (percentage of vital capacity = %VC and percentage of forced expiratory volume at 1 second = FEV1.0%) of these group showed typical abnormal values, and velocity ratio of 50% and 25% of maximum expiratory flow volume (V50/V25) of each groups were measured abnormal values (3.99 +/- 1.44 of Group O, 4.26 +/- 1.42 of Group R and 3.74 +/- 1.82 of Group M). The our strategy for these groups were a). Using skeletonization method for harvesting internal mammary artery (IMA) b) Take care not to injure the phrenic nerve and open the pleural cavity as surgical techniques (Harvesting IMA) and c) Administration of theophylline derivatives and corticosteroids to prevent bronchospasm d) Administration of concentrated serum albumin and diuretics to prevent pulmonary edema as therapeutic measures. The length of stay in the intensive care unit and ventilation time of each groups were not significantly longer. Patients of group M had more respiratory complications (atelectasis, pleural effusion, pneumothrax, bronchospasm, and pneumonia) than did patients of group R (p < 0.05), but did not more nonpulmonary complications and hospital deaths. The four in hospital deaths (2 with group O, 1 with group R and 1 with group M) were not directly related to pulmonary complications. Thus, result of CABG in patients with pulmonary impairment definitely proved to be satisfactory by our strategy, but mixed pulmonary diseased significantly had more pulmonary complications.

Cardiac Surgical Procedures↗

Multiple origins of fungal group I introns located in the same position of nuclear SSU rRNA gene.

The archiascomycetous fungus Protomyces pachydermus has two group I introns within the nuclear small subunit (nSSU) rRNA gene. One of these introns has an internal open reading frame (ORF) that encodes a predicted protein of 228 amino acid residues. On the other hand, Protomyces macrosporus has two group I introns that insert at the same positions as P. pachydermus, which have no ORF. Each alignment was constructed with Protomyces group I introns located in the same position and other introns retrieved by the BLAST Search. Each phylogenetic tree based on the alignment shows that Protomyces introns are monophyletic but the relationships among fungal introns do not reflect on the fungal phylogeny. Therefore, it is suggested that two different horizontal transfers of group I introns occurred at the early stage of Protomyces species diversification.

Ascomycota↗

Effects of daphnodorin A, B and C, new flavans isolated from traditional Chinese medicine, on the 12-lipoxygenase and cyclooxygenase metabolism of arachidonic acid in rabbit platelets.

The effects of daphnodorin A, B and C, isolated from the root and bark of Daphne odora THUNB, on the activities of 12-lipoxygenase and cyclooxygenase in rabbit platelets were examined. Daphnodorin A and C were inhibitors of platelet 12-lipoxygenase and cyclooxygenase activities. Daphnodorin B had no effect on the two enzymatic pathways. The present data raise the possibility that daphnodorin A and C can be anti-thrombotic and anti-atherosclerotic drugs through the suppressive influence on the platelet 12-lipoxygenase and cyclooxygenase.

12-Hydroxy-5,8,10,14-eicosatetraenoic Acid↗