PubMed Health⌕ Search

Biomedical subjects

Y Hoshikawa

Publications and source records attributed to Y Hoshikawa.

At least 19 recordsLinked to original sources
PubMed2006

[Bronchoplasty without lung resection for the complete transection of the left main bronchus due to blunt trauma].

Blunt bronchial injury is rare but crucial injury. A 17-year-old female was admitted due to traumatic injury. She was diagnosed with bilateral lung contusion, multiple rib fractures, spleen damage and the suspicion about the complete transection of the left main bronchus on X-ray and computed tomography (CT). She was brought to our hospital at 30 hours later from injury. Bronchoscopy revealed the complete transection and the edema of the left main bronchus. She underwent a resection of the disrupted portion and end-to-end anastomosis of left main bronchus without lung resection. We should be an immediate and accurate diagnosis of tracheobronchial disruption by X-ray, CT and bronchoscopy whenever we evaluate patients with blunt chest trauma.

Adolescent↗
PubMed2004

Effects of antiplatelet agents on pulmonary haemodynamic response to fMLP in endotoxin primed rats.

BACKGROUND: The interaction between neutrophils and platelets may be important in the modulation of pulmonary haemodynamics under systemic inflammatory conditions. A study was undertaken to examine whether antiplatelet agents inhibit platelet-neutrophil adherence and ameliorate the pulmonary haemodynamic response to fMLP by inhibiting thromboxane release in endotoxin primed lungs. fMLP stimulates neutrophils but not platelets; however, thromboxane synthesis in neutrophils is very low. METHODS: Rats were pretreated with either cilostazol (300 mg/kg) or aspirin (50 mg/kg) before endotoxin priming (5 mg/kg). Platelets in the lung were identified by fluorescent immunohistochemistry. Platelet-neutrophil adherence was analysed by flow cytometry of the lung vascular flush. The effect of fMLP (10(-6) M) on thromboxane release, lung weight (an indicator of pulmonary vasoconstriction), and lung filtration coefficient was determined in an isolated lung system perfused at a constant pressure difference. RESULTS: Endotoxin induced platelet accumulation and platelet-neutrophil adherence in the lung capillary were completely inhibited by cilostazol and aspirin while neutrophil recruitment was not affected. The fMLP challenge caused a significant increase in thromboxane B2 levels in endotoxin primed lungs. The fMLP induced decrease in lung weight was enhanced by endotoxin priming (from -4.9 to -63.9 mg, 95% CI of mean difference -99.5 to -10.5 mg, p<0.05). The fMLP induced increase in the lung filtration coefficient was also enhanced by endotoxin priming (from 0.63 to 2.40 mg/min/cm H2O/g, 95% CI of mean difference 1.17 to 2.37 mg/min/cm H2O/g, p<0.05). Treatment with cilostazol and aspirin completely inhibited the enhanced pulmonary haemodynamic response to fMLP. CONCLUSION: The neutrophil-platelet interaction is of critical importance in the modulation of pulmonary haemodynamics via thromboxane.

Animals↗
PubMed2002

[Metachronous lung cancer: indication and outcome].

Although lobectomy is the standard surgical treatment for primary lung cancer, it is unclear whether lobectomy will be benefit for patients with metachronous lung cancer. The purpose of this study is to evaluate the difference of benefit between lobectomy and limited resection at second lung resection. Forty-eight patients, who had already undergone lobectomy due to primary lung cancer, undergoing second lobectomy (n = 30) or limited resection (n = 18) for metachronous lung cancer were investigated. The over-all 5-year survival rate of second operation was 51.9%. Although there was no significant difference of 5-year survival rates between lobectomy and limited resection, 50.4% and 49.4%, respectively, lobectomy for T1N0 subset prolonged the survival compared to limited resection, 5-year survival rates, 69.6% and 31.7%, respectively. However, lobectomy resulted in more postoperative complications and less preservation of lung function. Lobectomy should be considered the surgical procedure of choice for patients with metachronous T1N0 lung cancer when lung function is preserved.

Aged↗
PubMed2001

Prostacyclin receptor-dependent modulation of pulmonary vascular remodeling.

Prostacyclin (PGI(2)) reduces pulmonary vascular resistance and attenuates vascular smooth muscle cell proliferation through signal transduction following ligand binding to its receptor. Because patients with severe pulmonary hypertension have a reduced PGI(2) receptor (PGI-R) expression in the remodeled pulmonary arterial smooth muscle, we hypothesized that pulmonary vascular remodeling may be modified PGI-R dependently. To test this hypothesis, PGI-R knockout (KO) and wild-type (WT) mice were subjected to a simulated altitude of 17,000 ft or Denver altitude for 3 wk, and right ventricular pressure and lung histology were assessed. The PGI-R KO mice developed more severe pulmonary hypertension and vascular remodeling after chronic hypoxic exposure when compared to the WT mice. Our results indicate that PGI(2) and its receptor play an important role in the regulation of hypoxia-induced pulmonary vascular remodeling, and that the absence of a functional receptor worsens pulmonary hypertension.

Animals↗
PubMed2001

Genomic approaches to research in pulmonary hypertension.

Genomics, or the study of genes and their function, is a burgeoning field with many new technologies. In the present review, we explore the application of genomic approaches to the study of pulmonary hypertension (PH). Candidate genes, important to the pathobiology of the disease, have been investigated. Rodent models enable the manipulation of selected genes, either by transgenesis or targeted disruption. Mutational analysis of genes in the transforming growth factor-beta family have proven pivotal in both familial and sporadic forms of primary PH. Finally, microarray gene expression analysis is a robust molecular tool to aid in delineating the pathobiology of this disease.

Animals↗
PubMed2001

Generation of oxidative stress contributes to the development of pulmonary hypertension induced by hypoxia.

Chronic hypoxia causes pulmonary hypertension and right ventricular hypertrophy associated with pulmonary vascular remodeling. Because hypoxia might promote generation of oxidative stress in vivo, we hypothesized that oxidative stress may play a role in the hypoxia-induced cardiopulmonary changes and examined the effect of treatment with the antioxidant N-acetylcysteine (NAC) in rats. NAC reduced hypoxia-induced cardiopulmonary alterations at 3 wk of hypoxia. Lung phosphatidylcholine hydroperoxide (PCOOH) increased at days 1 and 7 of the hypoxic exposure, and NAC attenuated the increase in lung PCOOH. Lung xanthine oxidase (XO) activity was elevated from day 1 through day 21, especially during the initial 3 days of the hypoxic exposure. The XO inhibitor allopurinol significantly inhibited the hypoxia-induced increase in lung PCOOH and pulmonary hypertension, and allopurinol treatment only for the initial 3 days also reduced the hypoxia-induced right ventricular hypertrophy and pulmonary vascular thickening. These results suggest that oxidative stress produced by activated XO in the induction phase of hypoxic exposure contributes to the development of chronic hypoxic pulmonary hypertension.

Acetylcysteine↗
PubMed2001

Experience with fatal interstitial pneumonia after operation for lung cancer.

BACKGROUND: The number of patients with lung cancer is increasing. This study was undertaken to realize the probability, fate and management of acute fatal postoperative complications. Since interstitial pneumonia was one of the most fatal postoperative complications, to know its incidence and fate is very important. METHODS: A total of 2667 patients who underwent thoracotomy caused by malignant tumors during the past 17 years were reviewed and studied. We performed investigations on medical records, chest X-rays, whole-body CT films, operative records and pathological specimens for all inpatients. RESULTS: Nineteen patients died in hospital 30 days after thoracotomy (operative death). Nine patients died in hospital more than 31 days after thoracotomy (hospital death). Eight cases out of 28 patients (operative and hospital deaths) developed and finally died by interstitial pneumonia. Each case was treated with steroids, neutrophil-elastase inhibitor, and/or immunosuppressive agents. These patients could not be selected by any preoperative laboratory examination, such as preoperative pulmonary function tests, serum biochemistry tests, and chest X-ray or CT films. Interstitial pneumonia as a complication of postoperative stage, was fatal and once developed, it was very difficult to save their lives. CONCLUSIONS: Since we reported the cases who died from acute postoperative complications, especially interstitial pneumonia, we could not present effective management. However, in this report, several therapeutic trials that may solve the problems of acute postoperative interstitial pneumonia were proposed.

Acute Disease↗
PubMed2001

[Ultra-slow infusion dynamic MRI using an infusion pump: a new method for the evaluation of drug distribution in arterial infusion chemotherapy].

Ultra slow infusion dynamic MR imaging using an infusion pump(IP-MRI) was performed in six patients with metastatic liver tumor or unresectable gastric cancer to evaluate ant-cancer drug distribution. We used un implanted port for the infusion of Gd-DTPA by infusion pump. On IP-MRI, the speed of Gd-DTPA infusion was very slow (0.01 ml/sec) , the same as drug infusion at chemotherapy. The contrast enhancement of tumors was extremely clear. Therefore, IP-MRI was considered feasible for the evaluation of drug distribution.

Adult↗
PubMed2000

Tumorigenesis of Epstein-Barr virus-positive epithelial cell lines derived from gastric tissues in the SCID mouse.

To study the tumorigenesis of Epstein-Barr virus (EBV)-positive epithelial cell lines GT38 and GT39 derived from human gastric tissues, we inoculated these cells under the skin of severe combined immunodeficient (SCID) mice. The development of tumors was observed in each of the mice about 2 months after the inoculation. The tumors were diagnosed with undifferentiated carcinoma by hematoxylin/eosin staining. EBV-encoded small RNA1 was detected in the paraffin-embedded tumor sections. The tumor cells had human chromosome. The circular, but not linear, EBV DNA was detected in the tumors. The molecular sizes of EBV DNA termini were the same as that of the inoculated GT38 or GT39 cells. The expressions of EBV nuclear antigen 2 and latent membrane protein 1 reduced in the tumors. Transcripts of BamHI C and W promoters in latency III were detected in the tumors and the cultured cells in vitro. The tumor cells were passaged from one SCID mouse to other SCID mice and to cultures in vitro. This is the first evidence that the EBV-positive epithelial cell lines produced tumors in the SCID mouse.

Animals↗
PubMed2000

An intrapulmonary teratoma associated with bronchiectasia containing various kinds of primordium: a case report and review of the literature.

An intrapulmonary teratoma (IPT), multiloculated and bronchiectatic, with two polyps inside a 23-year-old man is reported. The IPT, a very rare benign cystic lesion, was communicating with segmental bronchus and was removed by a segmental resection from the upper lobe of the left lung. The teratoma contained various kinds of primordial derivatives, such as mesoderm, ectoderm, and endoderm. Though 65 cases of IPT have been reported in the literature (1839-1996), in the present case there were over 15 germ derivatives, the largest number reported to date. The tumor contained thymic tissue, apart from mediastinum, which may be significant in relation to the pathogenesis of IPT. Clinical manifestations, age, and gender distributions and the kind of germ cell derivatives are discussed.

Adult↗
PubMed2000

Superoxide possibly produced in endothelial cells mediates the neutrophil-induced lung injury.

BACKGROUND: The mechanism by which stimulated neutrophils (polymorphonuclear leukocytes [PMNs]) damage pulmonary vascular endothelium was investigated. METHODS: The ability of unstimulated and mechanically stimulated PMNs to adhere to pulmonary endothelial cells and, thereby, alter pulmonary vascular permeability was tested. Each series was conducted on 6 rats. To stimulate PMNs, they were agitated gently in a glass vial for 10 seconds. RESULTS: Perfusing lungs with the stimulated PMNs elicited a fivefold increase in permeability compared with lungs perfused with the unstimulated cells. This increase in permeability was blocked completely by preincubation of stimulated PMNs with CD18 monoclonal antibody. This increase in permeability was also blocked completely by superoxide dismutase (SOD) or the xanthine oxidase (XO) inhibitor allopurinol. Pulmonary vascular hemodynamics were unaffected by any treatment protocol. The accumulation of stimulated PMNs within the lungs was not inhibited by SOD but was partially blocked by allopurinol. CONCLUSIONS: These findings suggest that stimulated PMN-induced increases in pulmonary vascular filtration resulted from endothelial cell injury caused by superoxide anion possibly generated by XO, exclusively present in the endothelial cells.

Animals↗
PubMed2000

Detection of Epstein-Barr virus in salivas and throat washings in healthy adults and children.

It is well known that Epstein-Barr virus (EBV) is excreted from oral regions in the patients with infectious mononucleosis. We analyzed the prevalence of EBV in saliva and throat washings from healthy people in Japan by the polymerase chain reaction assay. EBV DNA was detected in 43 (90%) of the 48 throat washings from healthy adults (21 to 57 years old) and in 35 (38%) of the 93 salivas from healthy children (0 to 6 years old). The percentages of the EBV DNA-positive ratio in salivas increased in proportion relative to the increase of the children's ages. EBV type 1 was predominant and was detected in 86 and 94% of adults and children, respectively. Umbilical cord lymphocytes were transformed by some throat washings from EBV seropositive donors. EBV DNA was detected in throat washings from two healthy adults whose EBV antibody was not detected. In both cases, higher amounts of EBV DNA were detected in their peripheral blood mononuclear cells than in those of other, EBV antibody-positive donors. These results demonstrated the incidence of EBV excretion in oral regions of healthy individuals in Japan and defined a novel type of EBV infection in healthy adults.

Adult↗
PubMed2000

Differential effect of TPA on cell growth and Epstein-Barr virus reactivation in epithelial cell lines derived from gastric tissues and B cell line Raji.

We characterized the cell growth and Epstein-Barr virus (EBV) reactivation for EBV infected epithelial cell lines, GT38, GT39, and GTC-4 using 12-O-tetradecanoylphorbol-13-acetate (TPA). These cell lines grew similarly in liquid medium, and formed colonies in soft agar. The cell growth was inhibited with TPA, dose-dependently in liquid medium. The colony formation was enhanced with low concentrations of TPA, but was inhibited with high concentrations. The latent EBV was reactivated with high concentrations of TPA as shown by the expression of EBV BZLF1 gene product ZEBRA. The effects of TPA on GTC-4 were compared with a Burkitt's lymphoma cell line Raji. The mode of actions of TPA in GTC-4 was different from Raji in terms of cell growth and EBV reactivation. The effective concentrations of TPA for cell growth inhibition and EBV reactivation were higher in Raji than GTC-4. Cell cycle analysis showed that TPA (20 ng/ml) induced cell cycle arrest to Raji but not to GTC-4; however, the rate of trypan blue stained cells increased in the TPA treated GTC-4 but not Raji. These results demonstrated that TPA affects differentially for the stimulation and inhibition of cell growth, and also EBV reactivation depends on TPA concentrations and cell types.

Blotting, Western↗
PubMed1999

Granulocytic differentiation of myeloid progenitor cells by p130, the retinoblastoma tumor suppressor homologue.

The retinoblastoma protein (pRB) and the related pocket proteins, p107 and p130, play crucial roles in mammalian cell cycle control. Recent studies indicate that these pocket proteins are also involved in cellular differentiation processes. We demonstrate in this work that the pRB-related p130 selectively accumulates during the in vitro differentiation of the myeloid progenitor cell, 32Dcl3, into granulocyte in response to granulocyte-colony stimulating factor (G-CSF). This G-CSF-dependent granulocytic differentiation is blocked by the adenovirus E1A oncoprotein, which binds to and inactivates the pRB family of pocket proteins including p130. Furthermore, enforced overexpression of p130 but not pRB inhibits the myeloid cell proliferation that is concomitantly associated with granulocytic differentiation morphologically characterized by nuclear segmentation. However, simple G1-cell cycle arrest induced by cytokine deprivation or ectopic overexpression of the p27 cyclin-dependent kinase inhibitor, or inhibition of E2F activities by dominant negative DP-1 is not sufficient to trigger granulocytic differentiation. The differentiation-promoting activity of p130 in myeloid cells requires both the pocket domain and the spacer domain. Our results indicate that the pRB-related p130 plays a critical role in myeloid cell differentiation and suggest that coupling of cell cycle exit with the cellular differentiation program may be specifically achieved by p130.

Adenovirus E1A Proteins↗
PubMed1999

Superoxide anion mediates pulmonary vascular permeability caused by neutrophils in cardiopulmonary bypass.

During cardiopulmonary bypass (CPB), neutrophils (PMNs) may be stimulated by shear stress which could contribute to the pulmonary injury that occurs after CPB. To elucidate whether mechanically stimulated PMNs increase pulmonary vascular permeability, measured as the pulmonary filtration coefficient (K) and pulmonary vascular resistance, and to elucidate whether superoxide anion mediates this increase, we assessed the effects of stimulated and unstimulated PMNs, and of superoxide dismutase (SOD) on K and resistance in isolated perfused lungs from Sprague-Dawley rats. PMNs were stimulated by gentle agitation in a glass vial for 10 s. Lungs perfused with the stimulated PMNs, being the stimulated group (n = 6), elicited a 5-fold increase in the filtration coefficient compared with lungs perfused with unstimulated cells, being the unstimulated group (n = 6). This increase in filtration was completely blocked by the preincubation of stimulated PMNs with CD18 monoclonal antibody, being the Ab group (n = 6), and also by superoxide dismutase, being the SOD group (n = 6). Pulmonary vascular resistance was not increased by stimulated PMNs, and the accumulation of stimulated PMNs was not blocked by SOD. These findings suggest that stimulated PMNs increase K and that superoxide anion may injure the pulmonary vascular endothelial cells.

Analysis of Variance↗
PubMed1999

Functional evaluations for pulmonary resection for lung cancer in octogenarians. Investigation from postoperative complications.

We have reviewed the records of our twenty-four patients aged 80 years or older who underwent lung resections for bronchogenic carcinoma between 1983 and 1997 in our department. Eighteen patients were male and six were female. Adenocarcinoma was the histology in more than half of the cases (13 patients), along with 8 squamous cell carcinoma, 2 large cell carcinoma, and one small cell lung carcinoma. More than single lobectomy was performed in each patient. Unilateral pulmonary occlusion tests were employed in patients with impairment in pulmonary functions. Every patient, who underwent the unilateral pulmonary occlusion test, was certified that the total pulmonary vascular resistance index during unilateral pulmonary arterial occlusion test was less than 700 dyne.sec.cm-5.m2. Postoperative cardiovascular complications, such as paroxysmal atrial tachycardia, premature atrial contraction, premature ventricular contraction or atrial fibrillation, were seen in 10 patients. Postoperative respiratory complications, namely, sputa retention, retained secretions or atelectasis, were seen in 7 patients. The extent of dissection of mediastinal lymph node was not correlated to the postoperative pulmonary complications. However, the incidence of arrhythmias in the patients who received R2 mediastinal lymphnode dissection was much higher than in those who received R1 or R0 dissection. Complete blood counts and serum biochemical analysis performed at about three weeks after operations revealed leukocytosis and increases in levels of serum transaminase. These phenomena in leukocytosis and increases in the levels of serum transaminase in these patients were similar to those in younger patients. There was no operative death. We conclude that some patients over 80 years are candidates for lung resection after careful preoperative cardiopulmonary evaluation.

Adenocarcinoma↗
PubMed1999

The interaction of mitogen-activated protein kinases to Epstein-Barr virus activation in Akata cells.

To understand the mechanism by which Epstein-Barr virus (EBV) is activated in Akata cells by cross-linking of surface immunoglobulin, the interaction between mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) and EBV activation was investigated. Immunoblotting using an anti-phosphoMAPK antibody (Ab) revealed that anti-IgG Ab induced rapid phosphorylation of MAPK in the cells. The phosphorylation was inhibited by MAPK/ERK kinase specific inhibitor, PD98059. The expressions of the EBV immediate early BZLF1 mRNA and its protein product ZEBRA, and early antigen were also inhibited by the inhibitor. These results indicate that MAPK is involved in the pathways of EBV activation.

B-Lymphocytes↗