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Biomedical subjects

R Maruyama

Publications and source records attributed to R Maruyama.

At least 37 records · Page 2Linked to original sources
PubMed2001

Clinical course and management of patients undergoing open window thoracostomy for thoracic empyema.

BACKGROUND: While open window thoracostomy (OWT) is a safe procedure and is indicated in patients who have thoracic empyema either with or without a bronchopleural fistula, it may prolong the hospital stay. OBJECTIVES: We retrospectively analyzed the relationship between the etiology of thoracic empyema and the open window interval (OWI). METHODS: Between January 1986 and May 1997, 53 patients resistant to conventional therapy underwent OWT for thoracic empyema at the Department of Surgery of the National Minami-Fukuoka Chest Hospital. The patients were classified into five groups based on the etiological findings of thoracic empyema. 44 patients also underwent closure of the window until June 1999. RESULTS: The average OWI was 180.4 +/- 51.9 (mean +/- SE) days for postoperative empyemas in lung cancer, 128.0 +/- 32.1 days for bacterial nontuberculous empyemas, 189.6 +/- 24.1 days for fungal empyemas, 365.8 +/- 201 days for empyemas caused by atypical mycobacteria and 322.0 +/- 58.7 days for tuberculous empyemas. There was no evidence that the OWI was related to either sex, age, etiology of thoracic empyemas, performance status, the existence of bronchopleural fistulae, complications of diabetes mellitus or preoperative malnutrition status in multivariable models. 5 patients underwent a second OWT because of recurrence of empyema. Mortality rate was 7.5%. CONCLUSIONS: There was no relationship between clinical factors including nutritional assessment and OWI. OWT generally is a safe and effective procedure for thoracic empyema resisting to conventional therapy except that it can make an extended hospital stay necessary.

Adult↗
PubMed2001

Apoptosis, rather than oncosis, is the predominant mode of spontaneous death of isolated adult rat cardiac myocytes in culture.

A number of isolated adult cardiomyocytes dies within a few days of culture and the mode of death has recently been suggested to be apoptosis, based on its association with the appearance of DNA fragmentation. However, morphological evidence is still lacking and precise analysis, including quantification, has not been performed. Adult rat ventricular cardiomyocytes isolated by enzymatic dissociation were incubated for 7 days in a serum-free medium (the rapid attachment model) and after various incubation periods, both attached and floating cells were counted and classified based on combined criteria of morphology and membrane permeability (dye exclusion): type 1, rod cells with intact membranes; type 2, non-rod cells with intact membranes; and type 3, non-rod cells with ruptured membranes. The number of both rod-shaped and dye-excluding cells decreased with the incubation period. After 7 days culture, the number of residual cells decreased to 12% of the initial value. Electron microscopy identified type 1 cells as viable, type 2 cells as viable or apoptotic, and type 3 as undergoing oncosis (primary necrosis) or secondary post-apoptotic necrosis. Ultrastructural morphometry revealed that oncotic cell death occurred predominantly during the early phase of culture whereas the more abundant apoptotic cell death occurred throughout the culture period. In conclusion, although both apoptotic and oncotic death occur in the natural course of adult rat cardiomyocytes in short-term culture, apoptosis is more predominant. Because of the high incidence of spontaneous cell death predominantly via apoptosis, this information is important for the interpretation of studies using this cell type in culture.

Animals↗
PubMed2001

Effects of amino acids on the amidation of polyaromatic carboxylic acids by Bacillus cereus.

The soil bacterium Bacillus cereus Tim-r01 efficiently transformed polyaromatic carboxylic acids (PACA) such as 4-biphenylcarboxylic acid (4-BPCA), 4-biphenylacetic acid, and 4-phenoxybenzoic acid into their corresponding amides. The amidation activity was expressed at 37 degrees C (pH 7-8) in the presence of grown cells in nutrients under an aerobic atmosphere. Other strains of B. cereus, IFO 3001 and IAM 1229, also gave the amide from 4-BPCA. In phosphate-buffered saline (PBS), the addition of normal amino acids was essential, while sulfur-containing amino acids such as methionine and cysteine drastically inhibited the amidation. Tracer experiments using N-15-isoleucine and N-15-alanine showed that the nitrogen atom of the amide came from an amino group of amino acids but not from ammonia or alkylamines.

Amides↗
PubMed2001

Hypertrophic pulmonary osteoarthropathy associated with non-small cell lung cancer demonstrated growth hormone-releasing hormone by immunohistochemical analysis.

Hypertrophic pulmonary osteoarthropathy (HPO) associated with non-small cell lung cancer in a 58-year-old man was accompanied by an elevated serum level of growth hormone (GH). HPO rapidly disappeared after resection of the primary tumor and the elevation of serum GH was resolved. Immunohistochemically the tumor contained growth hormone-releasing hormone (GHRH) but not GH. These findings suggest that the high serum GH level due to ectopic GHRH production in the tumor, was a contributing factor in HPO. This is the second reported case of non-small cell lung cancer which was immunohistochemically positive for GHRH associated with HPO.

Carcinoma, Non-Small-Cell Lung↗
PubMed2001

DNA methylation profiles of lung tumors.

Aberrant methylation of CpG islands in promoter regions of tumor cells is one of the major mechanisms for silencing of tumor suppressor genes. We determined the frequency of aberrant promoter methylation of the p16, adenomatous polyposis coli (APC), H-cadherin (CDH13), glutathione S-transferase P1 (GSTP1), O6-methylguanine-DNA-methyltransferase (MGMT), retinoic acid receptor beta-2 (RAR beta), E-cadherin (CDH1), and RAS association domain family 1A (RASSF1A) genes in 198 tumors consisting of small cell lung cancers [SCLCs (n = 43)], non-small cell lung cancers [NSCLCs (n = 115)], and bronchial carcinoids (n = 40). The profile of methylated genes in the two neuroendocrine tumors (SCLC and carcinoids) were very different from that of NSCLC. However, whereas the overall pattern of aberrant methylation of carcinoids was similar to that of SCLC, carcinoids had lower frequencies of methylation for some of the genes tested. There were also significant differences in the methylation profiles between the two major types of NSCLC, adenocarcinoma and squamous cell carcinoma. We performed cluster analysis and found that SCLCs clustered with other SCLCs and carcinoids but not with NSCLCs, whereas the NSCLCs tended to cluster together. Within NSCLCs, adenocarcinomas and squamous cell carcinomas clustered with their respective histological types. Finally, we compared the methylation profiles of SCLC and NSCLC tumors and their respective cell lines (n = 44). In general, methylation frequencies were higher in tumor cell lines, but these differences were seldom significant. Thus, tumor cell lines appear to be suitable models to study aberrant DNA methylation. We conclude that SCLC, carcinoids, squamous cell carcinomas, and adenocarcinomas of the lung have unique profiles of aberrant methylation. Our findings should help us understand differences in the pathogenetic mechanisms of lung cancers.

Adenomatous Polyposis Coli Protein↗
PubMed2000

Evaluation of p53 alterations in occult lymph node metastases.

BACKGROUND AND OBJECTIVES: This study was designed to evaluate p53 alterations in occult lymph node metastases. METHODS: We examined 41 patients with stage I non-small-cell lung cancer. We investigated p53 gene mutation by polymerase chain reaction and single-strand conformation polymorphism analysis of exons 5-8, p53 protein accumulation by immunostaining with monoclonal antibody DO-7, and detection of tumor cells in lymph nodes by immunohistochemistry with monoclonal antibodies to cytokeratin (CK). RESULTS: p53 gene mutation was detected in 34% of tumors and nuclear p53 accumulation in 46%. CK-positive cells in the hilar and mediastinal region lymph nodes were detected in 43.9% of patients and 29.3%, respectively. Of the 14 cases with p53 mutation and the 19 cases with p53 accumulation, 12 and 15 had micrometastases in the hilar or mediastinal lymph nodes, respectively. However, p53 alterations were not significantly associated with occult lymph node metastases. In cases with occult lymph node metastases, the 5-year survival was 81. 9% for the p53 wild-type group and 45.8% for the p53 mutation group. CONCLUSIONS: p53 alterations are not correlated with occult lymph node metastases, while p53 gene mutation is considered to be an unfavorable prognostic marker in patients with occult lymph node metastases. J. Surg. Oncol. 2000;73:143-147.

Aged↗
PubMed2000

Usefulness of magnetic resonance imaging for diagnosing deep anorectal abscesses.

PURPOSE: We evaluated the usefulness of magnetic resonance imaging for the preoperative diagnosis of deep anorectal abscesses. METHODS: Subjects were 21 patients with deep anorectal abscesses. Deep anorectal abscesses were classified into two types, ischiorectal and pelvirectal, according to their location. Patients were also classified into a single abscess group, which showed either an ischiorectal or pelvirectal abscess, and a double abscess group, which showed both ischiorectal and pelvirectal abscesses. The final diagnosis was made from surgical findings, and the types of deep anorectal abscesses determined by digital examination and magnetic resonance imaging were compared. RESULTS: Sensitivity of ischiorectal abscesses (20 lesions) with digital examination and magnetic resonance imaging was 75 and 95 percent, respectively, and that of pelvirectal abscesses (10 lesions) with digital examination and magnetic resonance imaging was 60 and 70 percent, respectively. Sensitivity of the magnetic resonance imaging was significantly higher than that of digital examination in ischiorectal abscesses. Diagnostic accuracy of digital examination and magnetic resonance imaging were both 83 percent in the single abscess group (12 patients), whereas in the double abscess group (9 patients) it was 22 and 78 percent, respectively. The rate of accurate diagnosis of magnetic resonance imaging compared with digital examination in the double abscess group was significantly higher than that in the single abscess group. CONCLUSION: Magnetic resonance imaging was useful for diagnosing and differentiating ischiorectal and pelvirectal abscesses.

Abscess↗
PubMed2000

Gallic acid induces vascular smooth muscle cell death via hydroxyl radical production.

In the present study, we investigated whether gallic acid (GA) can induce death in cultured vascular smooth muscle cells (VSMCs), and whether production of the hydroxyl radical (.OH) is involved in the process of GA action. GA killed cultured VSMCs from rat aorta, in a dosc- and time-dependent manner. Cytoplasmic shrinkage and nuclear condensation were observed light microscopically in GA-treated VSMCs, which appeared apoptotic. However, the ultrastructure of the VSMC was not typical of apoptosis: nuclear condensation was not glossy, and the plasma membrane and subccellular organelles were disrupted. Although the VSMC were positive for in situ nick end-labeling (TUNEL). they did not show a DNA ladder pattern on gel electrophoresis and were negative for T aq polymerase-based in situ ligation, which is more specific for apoptosis than TUNEL. Moreover. GA-induced cell death was not prevented by Boc-Asp-fmk (a pan-caspase inhibitor). Production of OH was detected in GA-treated VSMCs using high-performance liquid chromatography with salicylic acid as a trapping agent. Lipid peroxidation was also observed. The production of .OH was inhibited by catalase (CAT) and deferoxamine (DFX), and these treatments completely rescued VSMCs from cell death. In a cell-free system, GA produced .OH in the presence of Fe2+-EDTA, which was quenched by CAT and DFX, suggesting involvement of the Haber-Weiss reaction. Oxidative stress by reactive oxygen species, .OH in particular, is one of the mechanisms of GA-induced death of VSMCs, the mode of which was different from typical apoptosis.

Animals↗
PubMed2000

Video-assisted thoracoscopic treatment for spontaneous pneumothorax as two-day surgery.

BACKGROUND: To see whether video-assisted thoracoscopic surgery (VATS) for spontaneous pneumothorax (SP) as 2-day surgery is a safe and cost-effective procedure, we retrospectively compared VATS as 2-day surgery with standard VATS. METHODS: From April 1994 to March 2000, 139 SP patients were operated on: 115 patients were operated on by means of standard VATS and 24 were treated by 2-day surgery. The parameters we compared were the postoperative complications, hospitalization cost, and relapses. RESULTS: Excepting that 2 of those selected for 2-day surgery required another hospitalization, short-term complications were considered to be similar for the two groups. The median economic cost of 2-day surgery was about $5,822 US dollars and was lower than that of standard VATS. The difference in the recurrence rate between the two groups was not significant. CONCLUSIONS: We conclude that VATS as 2-day surgery is a safe and cost-effective procedure.

Adolescent↗
PubMed2000

Video-assisted thoracoscopic surgery for bilateral spontaneous pneumothorax in supine position: the use of a pillow beneath the back for intercostal space widening.

We performed a single stage video-assisted thoracoscopic surgery for bilateral spontaneous pneumothorax in the supine position with both arms abduced and the back slightly elevated using a pillow. While intercostal spaces were not open enough to insert a trocar, this procedure, not requiring the trouble of placing patients in the lateral decubitus position, is beneficial for the single treatment of bilateral thoracic discase.

Adult↗
PubMed2000

Ventilation- and carotid chemoreceptor discharge-response to hypoxia during induced hypothermia in halothane anesthetized rat.

It has been hypothesized that respiratory "gain" to hypoxic stimulus is not depressed in hypothermic animals though ventilation and that metabolic O(2) demand (Vo(2)) decreases with reduction in body temperature. The present study addressed this hypothesis by quantitative analysis of ventilatory and carotid chemoreceptor responsiveness to hypoxia during induced hypothermia in halothane anesthetized and spontaneously breathing rats. Rectal temperature was lowered from 37 degrees C (normothermia) to 30 and 25 degrees C by cooling body surface at comparable anesthetic depth without inducing shivering. Ventilation (V(E)), V(O2), PaO(2) and carotid chemoreceptor afferent discharges were measured during hyperoxic and hypoxic gas breathing. PaO(2) values at the same Fi(O2) (range 0. 35-0.08) decreased progressively as rectal temperature decreased. Both the V(E)/V(O2)- and chemoreceptor discharge-response curves shifted toward a lower PaO(2) range with a slight increase in the response slopes during hypothermia. The results indicated that the sensitivity of carotid chemoreceptor and ventilatory responses to hypoxia did not decrease at reduced body temperature. It is concluded that carotid chemoreceptor mediated regulation of ventilation is tightly coupled to changes in PaO(2 )range in halothane anesthetized rats during induced hypothermia.

Acid-Base Equilibrium↗
PubMed2000

[Preventive effects of various socks against adhesion of dermatophytes to healthy feet].

We studied the preventive effects of socks against dermatophyte infection. Wearing various socks (cotton socks, nylon stockings, wool socks and "tabi"), a healthy volunteer walked on a bath mat on which a patient with tinea pedis had stepped earlier. The volunteer pressed her right foot with socks onto large agar medium (Foot-press method), then, took off the socks and performed the Foot-press method again. The number of colonies of isolated dermatophytes on the medium was counted. The number of isolated colonies from the sole after taking off the nylon stockings was larger than that from the foot wearing the stockings. Dermatophytes were also isolated from the sole after taking off cotton socks. In contrast, few dermatophytes were isolated from the sole after taking off wool socks or "tabi". On microscopic observation, fibers of the nylon stockings and cotton socks were seen to be loose enough for dermatophytes to pass through. In contrast with those socks, fibers of wool socks and "tabi" were tight or fluffy. In conclusion, the nylon stockings and cotton socks are unsatisfactory in preventing the adhesion of dermatophytes.

Adult↗
PubMed2000

Angiotensin-converting enzyme-independent angiotensin formation in a human model of myocardial ischemia: modulation of norepinephrine release by angiotensin type 1 and angiotensin type 2 receptors.

Angiotensin II (Ang II) promotes norepinephrine (NE) release from cardiac sympathetic nerve endings. We assessed in a human model in vitro whether locally formed Ang II contributes to NE release in myocardial ischemia. Surgical specimens of human right atrium were incubated in anoxic conditions. After 70 min of anoxia, NE release (carrier-mediated; caused by NE transporter reversal) was 8-fold greater than normoxic release. Angiotensin-converting enzyme inhibition with enalaprilat failed to reduce anoxic NE release. In contrast, prevention of chymase-dependent Ang II formation with chymostatin, Bowman-Birk inhibitor, or alpha(1)-antitrypsin significantly inhibited anoxic, but not exocytotic, NE release. Two mast-cell stabilizers, cromolyn and lodoxamide, markedly reduced NE release, implicating cardiac mast cells as a major source of chymase. Angiotensin type 1 receptor (AT(1)R) blockade with EXP3174 inhibited NE release, whereas angiotensin type 2 receptor (AT(2)R) blockade with PD123319 did not. Interestingly, PD123319 reversed the inhibitory effect of EXP3174. Furthermore, synergisms were uncovered between EXP3174 and an AT(2)R agonist, and between EXP3174 and a Na(+)/H(+) exchanger inhibitor. Thus, angiotensin-converting enzyme-independent Ang II formation via chymase is important for carrier-mediated ischemic NE release in the human heart. Locally generated Ang II promotes NE release by acting predominantly at AT(1)Rs, which are likely coupled to the Na(+)/H(+) exchanger. Effects of Ang II at AT(2)Rs, seemingly opposite to those resulting from AT(1)R activation, are uncovered when AT(1)Rs are blocked. Because NE release is associated with coronary vasoconstriction and arrhythmias, and mast-cell density and chymase content increase in the ischemic heart, the notion that chymase-generated Ang II plays a major role in carrier-mediated NE release may have important clinical implications.

Aged↗
PubMed2000

Right ventricular aneurysm caused by acute myocarditis.

The first case of right ventricular aneurysm caused by acute myocarditis is reported. Positive gallium-67 uptake and contrast enhancement in the gadolinium diethylenetriaminepentaacetic acid-enhanced magnetic resonance images were detected in the apical region surrounding the aneurysm, suggesting transmural myocardial inflammations in the apical portion of the heart. The aneurysm was repaired surgically, and biopsy of the right ventricular myocardium showed replacement fibrosis and inflammatory infiltrate.

Acute Disease↗
PubMed1999

Multi-forms of human MTH1 polypeptides produced by alternative translation initiation and single nucleotide polymorphism.

The human MTH1 gene for 8-oxo-7,8-dihydrodeoxyguanosine triphosphatase, produces seven types (types 1, 2A, 2B, 3A, 3B, 4A and 4B) of mRNAs. The B-type mRNAs with exon 2b-2c segments have three additional in-frame AUGs in their 5' regions. We report here that these transcripts produce three forms of MTH1 polypeptides (p22, p21 and p18) in in vitro translation reactions. Three polypeptides were also detected in extracts of human cells, using western blotting. B-type mRNAs with a polymorphic alteration (GU-->GC) at the beginning of exon 2c that converts an in-frame UGA to CGA yielding another in-frame AUG further upstream, produced an additional polypeptide (p26) in vitro. Substitution of each AUG abolished the production of each corresponding polypeptide. Cell lines from individuals with the GC allele contain more B-type mRNAs than do those of GT homozygotes, and the former produce all of four polypeptides but the latter lack p26. Amounts of each polypeptide reflected copy number of the GC allele in each cell line. There is an apparent linkage dis-equilibrium between the two polymorphic sites, GT/GC at exon 2c and Val83/Met83 at codon 83 for p18.

Base Sequence↗
PubMed1999

Video-assisted thoracoscopic esophagomyotomy for achalasia after pulmonary lobectomy.

A 52-year-old man developed achalasia and a lung abscess due to aspiration pneumonia. We conducted a right upper lobectomy by thoracotomy for the abscess and, 2 weeks later, video-assisted thoracoscopic myotomy and fundoplication (modified Belsey Mark IV procedure) though the left thorax for achalasia. Three months after surgery, the patient was free of dysphasia and chest pain and had regained his original weight. Esophageal myotomy and fundoplication using video-assisted thoracoscopy appear to be feasible in treating achalasia involving impaired pulmonary function.

Endoscopy↗