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Biomedical subjects

A Watanabe

Publications and source records attributed to A Watanabe.

At least 55 records · Page 3Linked to original sources
PubMed2002

Biosynthetic pathway for production of a conjugated dienyl sex pheromone of a Plusiinae moth, Thysanoplusia intermixta.

Virgin females of Thysanoplusia intermixta (Lepidoptera; Noctuidae; Plusiinae) produce (5E,7Z)-5,7-dodecadienyl acetate as a main sex pheromone component. GC-MS analysis of the pheromone glands, which were treated with deuterated hexadecanoic, (Z)-11-hexadecenoic, and (Z)-7-dodecenoic acids, showed incorporation of the label into the dienyl component. Their incorporation rates confirmed that its biosynthesis proceeds in the following order: Delta11-desaturation of a C(16) acyl intermediate, chain shortening to a C(12) compound by beta-oxidation, Delta5-desaturation to produce a 5,7-dienyl system, reduction of the acyl group, and acetylation. These deuterated precursors also converted into a minor pheromone component, (Z)-7-docecenyl acetate, which might be prepared by the same pathway except for the step of Delta5-desaturation. While deuterium incorporation into the dienyl acetate was not observed in the extracts treated with other labeled dodecenoic acids with (E)-5-, (Z)-6-, and (E)-7-double bonds, the corresponding dodecenyl acetates were produced. This result showed low substrate specificity of the enzymes for reduction and acetylation. Labeled (Z)-10-hexadecenoic acid was not converted into a dodecenyl acetate, indicating the high substrate specificity of the enzyme for beta-oxidation.

Acetates↗
PubMed2002

Detection of Helicobacter pylori in cow's milk.

AIMS: To investigate the existence of Helicobacter pylori in cow's milk as one of the foods which most Japanese children eat. METHODS AND RESULTS: Detection of H. pylori was demonstrated by the semi-nested polymerase chain reaction (PCR), a culture method and electron microscopy. Semi-nested PCR demonstrated the ureA gene of H. pylori in 13 of 18 (72.2%) raw milk samples and in 11 of 20 (55%) commercial pasteurized milk samples. Helicobacter pylori binding immunomagnetic beads with H. pylori-specific goat anti-H. pylori antibody was shown by electron microscopy in both raw and pasteurized milk positive for the ureA gene. Helicobacter pylori was cultured in one raw milk sample, whereas it was not cultured in pasteurized milk samples. CONCLUSIONS, SIGNIFICANCE AND IMPACT OF THE STUDY: There is a possibility that cow's milk is a transmission vehicle in childhood H. pylori infection, although we failed to confirm the survival of H. pylori in pasteurized milk.

Animals↗
PubMed2002

Attenuated acute liver injury in mice by naked hepatocyte growth factor gene transfer into skeletal muscle with electroporation.

BACKGROUND: Hepatocyte growth factor (HGF) plays an essential role in hepatic development and regeneration, and shows proliferative and antiapoptotic activity in hepatocytes. AIMS: To establish an effective new method for HGF gene transfer in vivo and to investigate its effects in acute experimental liver injury. ANIMALS: Eight week old female mice were used. METHODS: Rat HGF gene in a modified pKSCX plasmid was transferred to the tibialis anterior muscle by electroporation using a pulse generator. Four days later, plasma HGF concentrations were determined by enzyme linked immunosorbent assay every two days for three weeks. To confirm the efficacy of electroporation, a plasmid bearing green fluorescence protein (GFP) was transferred similarly. Four days after electroporation, carbon tetrachloride (CCl(4)) was administered to mice to induce acute liver injury. Plasma alanine aminotransferase (ALT) activity was measured. Hepatic apoptosis was assessed by Hoechst 33258 staining and the TUNEL method. RESULTS: Fluorescence microscopy showed strong green fluorescence where the GFP gene had been transferred into muscle. In mice given the HGF gene, HGF in plasma was increased up to fourfold from pretreatment amounts, peaking 6-9 days after electroporation and quickly decreasing within three weeks. Compared with the group without HGF transfer, the percentage of apoptotic hepatocytes after CCl(4) intoxication was significantly lower, as was ALT activity. In addition, ALT activity normalised more rapidly in the HGF gene transfer group. CONCLUSIONS: Naked DNA injection and transfer by electroporation efficiently brings about HGF expression in vivo, which can attenuate acute liver injury.

Alanine Transaminase↗
PubMed2002

Ehlers-Danlos syndrome type IV with few extrathoracic findings: a newly recognized point mutation in the COL3A1 gene.

Ehlers-Danlos syndrome type IV (EDS IV) is caused by mutation within the COL3AI gene, resulting in the disorder of type III procollagen. The diagnosis is confirmed by demonstrating the synthesis of abnormal type III procollagen molecules from cultured dermal fibroblasts or by identifying the mutation in the COL3A1 gene. The authors report a case of EDS IV caused by a novel point mutation in the COL3A1 gene in a 16-yr-old female. Recurrent haemoptysis and cavitary formation of the lung were evidence of pulmonary involvement. However, extrathoracic manifestations of EDS IV were mostly absent. To the best of the authors' knowledge, all previously reported Ehlers-Danlos syndrome IV patients with respiratory disease had the characteristic findings or histories of Ehlers-Danlos syndrome IV. In the present case, connective tissue friability was suspected due to tissue laceration observed in the biopsied lung specimen, and the diagnosis was made beginning from this pivotal finding.

Adolescent↗
PubMed2002

[Multiple primary lung carcinoma].

Of 692 patients who underwent operations for primary lung carcinoma between January 1980 and August 2001, 21 (3.0%) were considered to have a second primary lung carcinoma, which was synchronous in 14 cases (2.0%) and metachronous in 7 cases (1.0%). Five-year survival rate for patients with synchronous and metachronous disease from initial treatment of carcinoma were 66.7% and 100%, respectively. Survival after the development of a metachronous lesion was 80.0% at 5 years. Eight of the synchronous second tumors (57%) were detected by preoperative radiography or bronchoscopy, and 3 (21%) were detected during the operation. Adenocarcinoma comprised 81% of all multiple primary lung carcinomas, 86% of synchronous carcinomas and 57% of metachronous carcinomas. It is important to carefully examine a synchronous lesion before and during the operation of a primary lung carcinoma and to perform close follow-up surveillance for early detection of a metachronous lesion. The outcomes of surgical treatment for either synchronous or metachronous multiple primary lung carcinomas are satisfactory. Precise staging is important for the treatment of multiple lung carcinomas, and an aggressive surgical approach should be considered for early-stage carcinomas.

Adult↗
PubMed2002

[Esophageal rupture just after the graft replacement of thoracoabdominal aorta for chronic aortic dissection].

A 51-year-old man with thoracoabdominal aortic aneurysm (DeBakey IIIb type chronic aortic dissection) first underwent the graft replacement of thoracic aorta with elephant trunk technique. Postoperatively, the residual false lumen just distal to the inserted graft as an elephant trunk enlarged in a short period, and it compressed the esophagus. He underwent the second graft replacement of thoracoabdominal aorta 2 months after the first surgery. Just after the second surgery, he had the esophageal rupture probably because of direct damage due to the enlarged aneurysm and loss of the arterial blood supply due to the graft replacement. He died of bleeding from the distal anastomosis because of the uncontrolled graft infection. It may have to be kept in mind that the esophageal rupture after the graft replacement could be one of the reason of the graft infection when the aortic aneurysm severely compressed the esophagus preoperatively.

Aortic Dissection↗
PubMed2002

[Anomalous systemic arterial supply to normal basal segment of the left lower lobe; report of a case].

A 28-year-old male was referred to our hospital because of hemoptysis. A chest X-ray revealed an increase of vascular marking in the left lower field and a partial defect in the lateral line of the descending thoracic aorta. An aortogram and pulmonary arteriogram showed a large artery arising from the descending thoracic aorta and supplying the left basal segment, which had no normal pulmonary arteries. A bronchoscopy showed no abnormal findings in the bronchial tree. A clinical diagnosis of systemic arterial supply to the basal segment of the left lower lung was made, and a left lower lobectomy and closure of the anomalous systemic artery by video-assisted thoracic surgery (VATS) were successfully performed. Vascular marking of the visceral pleura of left lower basal segment was observed and the anomalous arterial pressure was 84 mmHg, as high as systemic arterial pressure, during the procedure. The histopathological examination revealed normal alveolar structure, and sclerosis and hypertrophy of pulmonary arteries of the lesion (Heath-Edwards V, which means irreversible vascular changes due to pulmonary hypertension). The patient had an uneventful postoperative course and was discharged on postoperative day 8. The VATS procedure is a more useful and less invasive method for cases of systemic arterial supply to the basal segment of the left lower lung than an open thoracotomy.

Adult↗
PubMed2001

Complete genomic sequence of the filamentous nitrogen-fixing cyanobacterium Anabaena sp. strain PCC 7120.

The nucleotide sequence of the entire genome of a filamentous cyanobacterium, Anabaena sp. strain PCC 7120, was determined. The genome of Anabaena consisted of a single chromosome (6,413,771 bp) and six plasmids, designated pCC7120alpha (408,101 bp), pCC7120beta (186,614 bp), pCC7120gamma (101,965 bp), pCC7120delta (55,414 bp), pCC7120epsilon (40,340 bp), and pCC7120zeta (5,584 bp). The chromosome bears 5368 potential protein-encoding genes, four sets of rRNA genes, 48 tRNA genes representing 42 tRNA species, and 4 genes for small structural RNAs. The predicted products of 45% of the potential protein-encoding genes showed sequence similarity to known and predicted proteins of known function, and 27% to translated products of hypothetical genes. The remaining 28% lacked significant similarity to genes for known and predicted proteins in the public DNA databases. More than 60 genes involved in various processes of heterocyst formation and nitrogen fixation were assigned to the chromosome based on their similarity to the reported genes. One hundred and ninety-five genes coding for components of two-component signal transduction systems, nearly 2.5 times as many as those in Synechocystis sp. PCC 6803, were identified on the chromosome. Only 37% of the Anabaena genes showed significant sequence similarity to those of Synechocystis, indicating a high degree of divergence of the gene information between the two cyanobacterial strains.

Anabaena↗
PubMed2001

Leucine and its keto acid enhance the coordinated expression of genes for branched-chain amino acid catabolism in Arabidopsis under sugar starvation.

Branched-chain alpha-keto acid dehydrogenase (BCKDH), a multienzyme complex, plays a key role in branched-chain amino acid catabolism. However, it remains unclear whether expression of each subunit is coordinately regulated in plants, which should be important for the efficient assembly of subunits into a functional multienzyme complex. We show that the transcripts from the Arabidopsis E1alpha subunit gene accumulated in dark-adapted leaves and in sugar-starved suspension cells. These results are complementary to our previous report that the transcripts for the E1beta and E2 subunit genes accumulated in sugar-starved cells. Expression of the E1alpha gene is likely to be regulated by hexokinase-mediated sugar signaling, indicating that sugar plays a regulatory role in the coordinated expression of BCKDH subunit genes. Furthermore, Leu and its metabolite alpha-ketoisocaproate have synergistic effects on the enhanced expression of BCKDH subunit genes under sugar starvation. We hence suggest that branched-chain amino acids activate their own degradation pathway in sugar-starved cells through co-induction of each subunit gene of BCKDH.

3-Methyl-2-Oxobutanoate Dehydrogenase (Lipoamide)↗
PubMed2001

Pentaketide melanin biosynthesis in Aspergillus fumigatus requires chain-length shortening of a heptaketide precursor.

Chain lengths and cyclization patterns of microbial polyketides are generally determined by polyketide synthases alone. Fungal polyketide melanins are often derived from a pentaketide 1,8-dihydroxynaphthalene, and pentaketide synthases are used for synthesis of the upstream pentaketide precursor, 1,3,6,8-tetrahydroxynaphthalene (1,3,6,8-THN). However, Aspergillus fumigatus, a human fungal pathogen, uses a heptaketide synthase (Alb1p) to synthesize its conidial pigment through a pentaketide pathway similar to that which produces 1,8-dihydroxynaphthalene-melanin. In this study we demonstrate that a novel protein, Ayg1p, is involved in the formation of 1,3,6,8-THN by chain-length shortening of a heptaketide precursor in A. fumigatus. Deletion of the ayg1 gene prevented the accumulation of 1,3,6,8-THN suggesting the involvement of ayg1 in 1,3,6,8-THN production. Genetic analyses of double-gene deletants suggested that Ayg1p catalyzes a novel biosynthetic step downstream of Alb1p and upstream of Arp2p (1,3,6,8-THN reductase). Further genetic and biochemical analyses of the reconstituted strains carrying alb1, ayg1, or alb1 + ayg1 indicated that Ayg1p is essential for synthesis of 1,3,6,8-THN in addition to Alb1p. Cell-free enzyme assays, using the crude Ayg1p protein extract, revealed that Ayg1p enzymatically shortened the heptaketide product of Alb1p to 1,3,6,8-THN. Thus, the protein Ayg1p facilitates the participation of a heptaketide synthase in a pentaketide pathway via a novel polyketide-shortening mechanism in A. fumigatus.

Alcohol Oxidoreductases↗
PubMed2001

Impaired suppression of processing in schizophrenic patients suggested by ERPs obtained in a selective attention task.

In the present study, we focused on the ability of suppression of processing in schizophrenic patients, using event-related potentials (ERPs) recorded during a selective attention task. During the task, subjects were required to focus on one ear, counting deviant stimuli, those deviating in duration from a sequence of standard stimuli. We compared amplitude data of two positive components differing in latency elicited by standard stimuli, which reflect suppression of stimulus processing, between schizophrenic patients and normal controls. Significant between-group differences were obtained specifically in the right ear attended condition, suggesting impaired suppression of processing in schizophrenics mediated in the left hemisphere.

Adult↗
PubMed2001

Identification of the protein product of the Coch gene (hereditary deafness gene) as the major component of bovine inner ear protein.

In order to better understand the cause of hereditary hearing impairment, we have performed a proteomic analysis of the inner ear proteins using two-dimensional gel electrophoresis. In the process of analysis, we have found very unique properties of the bovine homologue of the human COCH gene product. The COCH gene is responsible for one of the hereditary hearing impairments, DFNA9, and was recently suggested to be a possible genetic factor contributing to Ménière's disease. The Coch protein constitutes 70% of bovine inner ear proteins and is composed of 16 different protein spots, with charge and size heterogeneity. Heterogeneity of this protein suggests that the Coch gene is processed in several ways, at the transcriptional and/or posttranslational level. Much knowledge has accumulated about the hereditary hearing impairment genes; however, little research has been done regarding the protein products of those genes. This is the first report to characterize the Coch protein. Study of the Coch protein might provide more information on the mechanism of hearing and vestibular disorders.

Amino Acid Sequence↗
PubMed2001

High-pressure NMR study of cis-1,n-disubstituted[n]paracyclophanes. Effect of increased pressure on the hindered internal rotation.

The effect of hydrostatic pressure on the rate of internal rotation of title compounds has been examined by the DNMR method. Quartz pressure-resisting NMR cells were used to realize the high-pressure experiments up to 390 (line shape measurements) and 450 MPa (chemical shift measurements). Application of hydrostatic pressure was found to accelerate the rotation of the benzene ring, while pressure-induced low-frequency chemical shifts of bridge methylene protons indicated that there is a considerable shrinkage of the methylene bridge structure upon pressurization.

Journal Article↗
PubMed2001

Production of recombinant bovine lactoferrin N-lobe in insect cells and its antimicrobial activity.

Lactoferrin is a multifunctional, iron-binding glycoprotein found in physiological fluids of mammals. In the present study, a gene encoding the N-terminal half (N-lobe) of bovine lactoferrin was cloned and expressed in cultured insect cells using a baculovirus expression system. One mutation was found in the lactoferrin N-lobe gene, but it resulted in no amino acid substitution. The recombinant lactoferrin N-lobe was secreted into the culture medium and partially purified by means of an immobilized heparin column. The recombinant lactoferrin N-lobe secreted was not glycosylated, but it possessed antimicrobial activity toward Escherichia coli O111. The recombinant product synthesized and accumulated in the host cells exhibited greater electrophoretic mobility on SDS-PAGE than the secreted product and showed no potency to inhibit the growth of bacteria. It is thought that the product accumulated intracellularly lacks antimicrobial ability due to its degradation in the host cells or due to disruption of the active conformation.

Animals↗
PubMed2001

Simultaneous cardiac operations with pulmonary resection for lung carcinoma.

OBJECTIVES: A procedure remains to be established for managing patients with both cardiac and pulmonary diseases requiring surgical interventions. We review our experience with 6 patients having cardiac disease and lung cancer surgically treated simultaneously to determine whether simultaneous surgery is safe and effective. METHODS: Subjects were 6 men with a mean age of 64 +/- 10 years undergoing cardiac surgery combined with pulmonary lobectomy from January 1986 through June 2000. Cardiac procedures consisted of coronary artery bypass in 3, coronary artery bypass plus left ventricular aneurysm repair, aortic valve replacement, and minimally invasive direct coronary artery bypass surgery in 1 patient each. All underwent lobectomy. RESULTS: No early deaths occurred. Bleeding complications occurred in 2 patients and lymph node dissection was incomplete in 3. Two died of carcinoma-related events, 1 at 28 and the other at 84 months after surgery. One died suddenly from a cardiac-related event 42 months after surgery. Only 1 patient is currently alive and disease-free at 104 months after surgery. CONCLUSION: Simultaneous surgery can be conducted with acceptable mortality. The occurrence of bleeding complications and incomplete lymph node dissection, however, indicates combined procedures only in patients requiring simultaneous surgery due to their disease or unable to tolerate a second operation.

Aged↗
PubMed2001

Phase I/II and pharmacologic study of irinotecan and carboplatin for patients with lung cancer.

PURPOSE: To determine the maximum tolerated dose (MTD) of irinotecan combined with carboplatin, to evaluate its efficacy and toxicity for patients with lung cancer, and to examine its pharmacokinetics and pharmacodynamics. METHODS: The dose of irinotecan was escalated from 40 mg/m2 per week in increments of 10 mg/m2. Carboplatin was fixed at 300 mg/m2. Multivariate regression models with an interaction term were used to evaluate synergistic pharmacodynamic interactions. RESULTS: The MTD and recommended dose of irinotecan were 60 and 50 mg/m2, respectively. Dose-limiting toxicities were grade 4 neutropenia and grade 3 or 4 diarrhea. In phase II studies, response rates were 81.3% (95% confidence interval 61.8-100%) in 16 patients with small-cell lung cancer and 22.2% (2.7-41.8%) in 18 patients with non-small-cell lung cancer. Two patients (6%) experienced grade 4 neutropenia, thrombocytopenia, and grade 3 diarrhea. The area under the plasma concentration versus time curve (AUC) of carboplatin ranged from 2.87 to 9.31 mg x min/ml, with a median of 4.66 mg x min/ml. In pharmacodynamic analyses, the log-transformed surviving fraction in platelet count (SFp) showed a significant association with the AUC of carboplatin (P=0.010), while that in neutrophil count (SFn) was not significantly correlated with any pharmacokinetic parameter. The interaction term was not significant in either case. CONCLUSIONS: These results indicate that AUC-based dosing of carboplatin is still rational in combination chemotherapy. A more sensitive method for predicting life-threatening toxicities is needed, however, because traditional pharmacokinetic parameters were not adequate tools for identifying patients at high risk of severe neutropenia and diarrhea. This combination regimen has only modest activity, and further studies are necessary to evaluate a different dose schedule.

Adult↗
PubMed2001

A ruptured pancreaticoduodenal artery aneurysm associated with a splenic artery aneurysm: report of a case.

True pancreaticoduodenal artery (PDA) aneurysms are extremely rare. We report herein a case of a ruptured PDA aneurysm associated with a nonruptured splenic artery aneurysm which was successfully treated by surgery. A 55-year-old man was admitted to a local hospital complaining of sudden abdominal and back pain, and thereafter he was transferred to our university hospital. Abdominal computed tomography revealed retroperitoneal hematoma and an enhanced round spot suggesting a peripancreatic aneurysm. Emergency angiography showed a 20-mm-sized aneurysm in the inferior PDA and a 10-mm-sized aneurysm in the splenic artery. The patient underwent an emergency laparotomy with a diagnosis of a ruptured PDA aneurysm. After evacuating a large volume clot in the right retroperitoneal space and the peritoneal cavity, we detected an index finger-sized aneurysm with arterial bleeding in the right inferioposterior aspect of the pancreas. Hemostasis was obtained by oversewing the aneurysm and a ligation of the feeding arteries. A prophylactic splenectomy was performed for the nonruptured splenic artery aneurysm. This case indicates that emergency angiography is indispensable for both a definitive diagnosis and adequate surgical treatment of PDA aneurysms.

Aneurysm↗