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N Hasegawa

Publications and source records attributed to N Hasegawa.

At least 19 recordsLinked to original sources
PubMed2006

Expression of clusterin, XIAP and survivin, and their changes by camptothecin (CPT) treatment in CPT-resistant PC-3 and CPT-sensitive LNCaP cells.

AIM: Clusterin and IAPs (inhibitor of apoptosis proteins), such as survivin and XIAP, are known to be related to chemo-resistance in several cancer cells. In the current study, we investigated their expression levels in human prostate cancer cell lines, LNCaP and PC-3 which are sensitive and resistant to camptothecin (CPT), topoisomerase I inhibitor, respectively. METHODS: LNCaP and PC-3 cells were cultured in the presence of CPT, cell death was evaluated using Hoechst 33342 and propidium iodide (PI) double staining. The expression of clusterin, XIAP and survivin on mRNA and protein levels was investigated by semi-quantitative RT-PCR and Western blotting, respectively. RESULTS: Our data showed that 24 h treatment of LNCaP cells with 0.5 and 3.0 microM CPT resulted in higher number of apoptotic cells, than that in PC-3 cells. Western blot analysis revealed that the clusterin level in PC-3 cells was 5-fold higher than that in LNCaP cells. In contrast, XIAP expression level in PC-3 cells was lower than that in LNCaP cells, and survivin levels were similar in these two cell lines. Treatment with 0.5 and 3.0 microM CPT resulted in the reduced survivin and XIAP expression in both cell lines, while clusterin expression remained unchanged in LNCaP cells, but was increased in PC-3 cells. CONCLUSION: The results suggest that clusterin may take a greater part in CPT-resistance than survivin and XIAP in PC-3 cells.

Antineoplastic Agents, Phytogenic↗
PubMed2004

High prevalence rate of Helicobacter pylori resistance to clarithromycin during long-term multiple antibiotic therapy for chronic respiratory disease caused by non-tuberculous mycobacteria.

BACKGROUND: Helicobacter pylori resistance to clarithromycin, probably due to the frequent use of this antibiotic for the treatment of other diseases, is the greatest obstacle against its eradication. AIM: To clarify the prevalence of clarithromycin-resistant H. pylori in patients with non-tuberculous mycobacterial lung disease receiving multiple antibiotic treatment, including clarithromycin. METHODS: We enrolled 88 patients with non-tuberculous mycobacterial lung disease; 29 underwent upper gastrointestinal endoscopy for the diagnosis of H. pylori infection prior to treatment, and 60 underwent it during treatment. The diagnosis of H. pylori infection was confirmed by histological examination, urease test and microaerobic bacterial culture. The minimum inhibitory concentration of clarithromycin was determined and the DNA was analysed for each of the isolated H. pylori strains. RESULTS: Patients during the treatment had a high prevalence rate of clarithromycin-resistant H. pylori (100%). Analysis of DNA of the clarithromycin-resistant H. pylori isolates revealed point mutations at A2142G or A2143G. Moreover, a linear correlation was found between the total cumulative dose of clarithromycin and the minimum inhibitory concentration. CONCLUSION: All patients with non-tuberculous mycobacterial lung disease being treated long-term with multiple antibiotics, including clarithromycin, harboured clarithromycin-resistant H. pylori in the stomach. Therefore, eradication of H. pylori before commencement of long-term therapy including clarithromycin should be recommended.

Anti-Bacterial Agents↗
PubMed2003

Covered expandable metallic stent placement for hemostasis of colonic bleeding caused by invasion of gallbladder carcinoma.

A 72-year-old Japanese man was admitted to our hospital complaining of right upper-quadrant abdominal pain, blood in his stool, and symptoms of anemia. On physical examination a hard mass, about 6 cm in diameter, was palpable in the right upper quadrant of the abdomen. Computed tomography revealed a gallbladder carcinoma which had invaded the transverse colon, with liver metastasis. We diagnosed gallbladder carcinoma, stage IVB. Colonoscopy was performed for persistent blood in the stools. This revealed an elevated lesion which appeared to be an invasion of gallbladder carcinoma, with diffuse bleeding from the right-side of the transverse colon. It proved difficult to stop this bleeding by ordinary therapeutic endoscopy. In order to achieve hemostasis we therefore inserted a covered Ultraflex metallic stent to compress the tumor. After stent placement, blood was no longer seen in the patient's stools, he became able to eat soft food and was discharged. This treatment was uninvasive and effective. Covered stent placement appears to be a new and useful method in the management of bleeding from malignant gastrointestinal tumors.

Aged↗
PubMed2002

Picosecond snapshot of the speckles from ferroelectric BaTiO3 by means of x-ray lasers.

A picosecond x-ray laser speckle has been conducted to study the dynamics of a disordered surface domain structure (BaTiO3 with 90 degrees c/a domains) as a function of temperature for the first time. The transient surface structures induced by ferroelectric domains decrease as temperature increases towards the Curie temperature T(c) and completely disappear above T(c). The dramatic change of the spatial configuration of the c/a domains was observed to occur from a temperature 2 degrees C below T(c), near which the average correlated domain size at equilibrium decreases as (T(c)-T)(0.37+/-0.02).

Journal Article↗
PubMed2002

Seasonal variations of 222Rn concentrations in the air of a tunnel located in Nagano city.

The seasonal variation of 222Rn concentrations in the air of tunnels constructed during World War II at Nagano City has been investigated. The determination of 222Rn concentrations in tunnel air was performed using a solid-state nuclear track detector technique. The monthly radon concentrations changed smoothly, decreasing towards winter and increasing towards summer, and it was found that the concentrations strongly correlate with the temperature difference between the inside and the outside of the tunnel. In the innermost areas of the tunnel, the maximum concentration was observed in July, its value being about 6500 Bq m (-3). The concentrations of radon in the tunnel air decrease exponentially towards the openings of the tunnel, which indicates that the radon concentration in the tunnel is basically governed by diffusion and mixing of radon gas with air. These observations lead to the conclusion that the seasonal variation of the radon concentration in the tunnel air is mainly caused by a convection current due to a stack effect induced by the temperature difference between the tunnel air and the outside air.

Air Movements↗
PubMed2002

Detection of mycobacteria in patients with pulmonary tuberculosis undergoing chemotherapy using MGIT and egg-based solid medium culture systems.

SETTING: National Minami-Yokohama Hospital, Kanagawa, Japan. OBJECTIVE: To compare the performance of a liquid medium system using the Mycobacteria Growth Indicator Tube (MGIT) with that of the conventional Japanese culture system using egg-based Ogawa medium, equivalent to Lowenstein-Jensen medium, in cases with pulmonary tuberculosis on chemotherapy. DESIGN: A single-centre prospective case study of 61 hospitalised patients from 1 May to 31 July 1998 on a standard 6-month regimen of anti-tuberculosis chemotherapy including isoniazid, rifampin, streptomycin or ethambutol, and pyrazinamide. Sputum cultures using both culture systems were performed bi-weekly up to week 16 of treatment, and were further monitored by MGIT alone at the end of chemotherapy and every 6 months after the end of chemotherapy up to 2 years. RESULTS: The detection time by MGIT gradually became longer with the progression of chemotherapy. The recovery rate at weeks 2, 4, 6, 8, and 10 by MGIT were significantly higher (P < 0.05) than on the Ogawa slants. Although one case was microbiologically diagnosed as a relapse, using the more sensitive MGIT system did not increase the relapse rate. CONCLUSION: The gradual prolongation of detection time with the progression of treatment and an attainment of negativity of sputum culture at 4 months after chemotherapy could be a useful intermediate marker to monitor the efficacy of treatment for patients with pulmonary tuberculosis by the MGIT system. Further evaluation is necessary to establish the utility of MGIT in monitoring the treatment process.

Antitubercular Agents↗
PubMed2001

Two c-type cytochromes, NirM and NirC, encoded in the nir gene cluster of Pseudomonas aeruginosa act as electron donors for nitrite reductase.

Three c-type cytochromes, NirM, NirC, and NirN, are encoded in the nirSMCFDLGHJEN gene cluster for cytochrome cd(1)-type nitrite reductase (NIR) of Pseudomonas aeruginosa. nirS is the structural gene for NIR. NirM (cytochrome c(551)) is reported to be a physiological electron donor for nitrite reductase. The respective functions of NirC and NirN have remained unclear. In this study, we produced recombinant NirC and NirN in P. aeruginosa, and purified them from the periplasmic fraction. N-terminal amino acid sequences of the purified proteins showed that the N-terminal 31 and 18 residues of NirC and NirN precursors were cleaved, respectively, indicating that cleaved peptides act as signals for membrane translocation. In addition, the ability of NirC for electron donation to nitrite reductase was investigated. NirC, as well as NirM, was able to mediate the electron donation from the membrane electron pathway to NIR, suggesting that the structural gene for NIR is followed by the genes for two electron donors for NIR.

Anion Transport Proteins↗
PubMed2001

Garcinia extract inhibits lipid droplet accumulation without affecting adipose conversion in 3T3-L1 cells.

Garcinia extract was isolated from the fruit of the Garcinia cambogia and was used as a potential antiobesity agent. In week 3 of culture with insulin, the fat cells exhibited more numerous and larger intracytoplasmic lipid droplets (i.e. 30-40 microm(2)). When Garcinia extract and insulin were added simultaneously, the accumulation of lipid droplets was inhibited and the peak droplet area shifted to become smaller (10-20 microm(2)). The activities of glycerophosphate dehydrogenase, a marker of adipose differentiation, were not significantly inhibited by the Garcinia extract. These findings suggest that the Garcinia extract inhibits lipid droplet accumulation in fat cells without affecting adipose conversion.

3T3 Cells↗
PubMed2001

Relationship between lesion location and the outcome of pallidotomy for Parkinson's disease.

The relationships between lesion location and clinical outcome following posteroventral pallidotomy for Parkinson's disease were studied. Forty-four patients were operated forty-six times and studied with neurological and psychological examinations before and after pallidotomy. Lesion location was confirmed using films with a coagulation electrode which were X-rayed during the operation. Changes of intelligence were observed in the patients with anteromedial lesions. Wearing-off phenomenon in four patients and dopa-induced dyskinesia in three patients were not improved following pallidotomy in twenty patients with severe wearing-off and dyskinesia. Lesions in the patients with no improvement of wearing off were located more lateral and those in the patients with sustained severe dyskinesia were located more dorsal in the internal part of the globus pallidus. It may be concluded that clinical outcome is related to lesion location.

Antiparkinson Agents↗
PubMed2001

Trehalose suppresses lipopolysaccharide-induced osteoclastogenesis bone marrow in mice.

We have previously shown that trehalose suppresses bone loss in ovariectomized (OVX) mice by way of inhibiting osteoclast differentiation in bone marrow. Also, trehalose inhibits the secretion of interleukin-6 in bone marrow cell cultures, resulting in a decrease in osteoclast formation. In this study, we examined the effect of trehalose on osteoclastogenesis using another model of bone resorption, namely lipopolysaccharide (LPS)-stimulated osteoclast induction. Mice were given trehalose (1g/kg) by gastric intubation for 5 consecutive days, and 24 hours later, 14 mg/kg of LPS was injected intraperitoneally. Trehalose significantly suppressed LPS-induced tumor necrosis factor (TNF)-alpha production after 90 min and decreased the number of osteoclasts in the bone marrow 48 hours after LPS injection. These results indicate that trehalose suppresses excessive osteoclastogenesis not only in OVX mice but also in a LPS-induced bone resorption mouse model and further suggest that the latter finding may be mediated at least in part through a decrease in TNF-alpha production.

Journal Article↗
PubMed2001

Organization of inputs from cingulate motor areas to basal ganglia in macaque monkey.

The cingulate motor areas reside within regions lining the cingulate sulcus and are divided into rostral and caudal parts. Recent studies suggest that the rostral and caudal cingulate motor areas participate in distinct aspects of motor function: the former plays a role in higher-order cognitive control of movements, whereas the latter is more directly involved in their execution. Here, we investigated the organization of cingulate motor areas inputs to the basal ganglia in the macaque monkey. Identified forelimb representations of the rostral and caudal cingulate motor areas were injected with different anterograde tracers and the distribution patterns of labelled terminals were analysed in the striatum and the subthalamic nucleus. Corticostriatal inputs from the rostral and caudal cingulate motor areas were located within the rostral striatum, with the highest density in the striatal cell bridges and the ventrolateral portions of the putamen, respectively. There was no substantial overlap between these input zones. Similarly, a certain segregation of input zones from the rostral and caudal cingulate motor areas occurred along the mediolateral axis of the subthalamic nucleus. It has also been revealed that corticostriatal and corticosubthalamic input zones from the rostral cingulate motor area considerably overlapped those from the presupplementary motor area, while the input zones from the caudal cingulate motor area displayed a large overlap with those from the primary motor cortex. The present results indicate that a parallel design underlies motor information processing in the cortico-basal ganglia loop derived from the rostral and caudal cingulate motor areas.

Action Potentials↗
PubMed2001

New bronchoscopic microsample probe to measure the biochemical constituents in epithelial lining fluid of patients with acute respiratory distress syndrome.

OBJECTIVE: A noninvasive bronchoscopic microsampling (BMS) probe was developed to sample biochemical constituents of the epithelial lining fluid in small airways. DESIGN: Observational, controlled study. SETTING: Intensive care unit of academic medical center. PATIENTS AND PROCEDURE: BMS was applied in a control group of seven patients who had hemoptysis or small solitary peripheral nodules but no hypoxemia or other signs of acute inflammation and in four patients with acute respiratory distress syndrome (ARDS), to test whether BMS can ascertain the presence of acute pulmonary inflammation without complications. MEASUREMENTS AND RESULTS: Complications, including a significant decrease in arterial oxygen saturation, were observed neither during nor after BMS. In the ARDS group, albumin, lactate dehydrogenase, interleukin-6, basic fibroblast growth factor, and neutrophil elastase concentrations in epithelial lining fluid were significantly higher (p <.0001, p =.012, p <.0001, p <.0001, and p <.0001, respectively) than in the control group. Serial BMS was safely performed in one patient with ARDS, allowing us to observe a correlation between changes in the concentration of inflammation-related biochemical markers and clinical course of the disease. CONCLUSIONS: These results suggest that BMS is safe and useful to monitor pulmonary biochemical events in ARDS.

Adult↗
PubMed2001

Pretreatment with FK506 improves survival rate and gas exchange in canine model of acute lung injury.

The novel effects of FK506 on shock induced by lipopolysaccharide and phorbol myristate acetate (LPS/PMA) were studied using beagles. Five groups were studied: endotoxin shock control group (both 0.5 mg/kg of LPS and 30 microg/kg of PMA, n = 6); methylprednisolone-treated endotoxin shock group (n = 5); FK506-treated endotoxin shock groups in which intravenous infusions of FK506 at 2.5 microg/kg/h (low dose, n = 5), 8 microg/kg/h (medium dose, n = 5), and 25 microg/kg/h (high dose, n = 5) were administered. In the control group, the survival rate was 33%. Also, arterial hypoxemia, systemic hypotension, and marked increases in pulmonary vascular resistance (PVR) and wet-to-dry weight ratio (W/D) were observed. FK506 treatment at both medium and high doses significantly attenuated these LPS/PMA-induced physiological changes, and the survival rates were 80 and 100%, respectively. On the other hand, in the methylprednisolone group, no obvious effects were observed. The present study suggests that FK506 could have prophylactic potential against acute lung injury in endotoxin shock.

Animals↗
PubMed2001

Usefulness of pulmonary vascular leakiness assessment in interstitial pneumonitis.

STUDY OBJECTIVE: Pulmonary vascular leakiness of (67)Ga-circulating transferrin in interstitial pneumonitis (IP) was estimated by our previously described method, and its ability to evaluate disease activity was compared with conventional (67)Ga scintigraphy. DESIGN: Using 30-min dynamic scanning data after IV injection of (67)Ga citrate, the exponential equilibration coefficient of (67)Ga between the intravascular and pulmonary interstitial compartments was calculated and defined as the leak index (LI). Pulmonary (67)Ga uptake was assessed by gallium index, determined by conventional static images taken 48 h after (67)Ga citrate injection. SETTING: Hospitalized patients. PARTICIPANTS: The study population consisted of 17 control patients and 20 patients with IP. RESULTS: The mean LI in patients with IP was significantly higher than in the control group (p < 0.0001), whereas no significant increase in gallium index was noted between the IP group and the control group. No significant correlation was found between gallium index and LI among all study participants. Mean LI in patients with active IP was significantly higher than in patients with stable IP (p = 0.0024). CONCLUSIONS: An increase in pulmonary vascular leakiness was found in patients with IP. LI may be useful to assess the disease activity.

Adult↗
PubMed2001

[Anesthetic management of a patient with gunshot injury in the neck and the chest].

We present a case of a 27-year-old man with gunshot injury in the neck and the chest. On admission, he had an entry wound in the neck and his chest radiograph showed left hemopneumothorax. Nasal endotracheal intubation and chest drainage were immediately performed. Angiography revealed pseudoaneurysm of the left carotid artery and fistula between the artery and the innominate vein. The patient showed progressive severe facial edema due to the fistula. Anesthesia was induced and maintained with fentanyl and sevoflurane. The carotid artery was repaired with an autologous saphenous vein graft. Although one lung ventilation (OLV) was requested for partial resection of the left lung, replacing the endotracheal tube was impossible due to severe facial edema. OLV was successfully performed by blocking the left main trunchus with a 7 Fr Fogarty catheter placed under fiberscopic monitoring. The patient recovered without any serious complications. Prompt and proper airway management is required in gun shot injury of the neck and chest.

Adult↗
PubMed2001

[Simultaneously detected double malignancies on a duplicated kidney associated with atrophied counterpart: a case report].

A case of simultaneous double malignant tumor in the same kidney, associating renal cell carcinoma with renal pelvic transitional cell carcinoma, in a 70 year-old-male was reported. On January 6, 2000 he presented with macroscopic hematuria. There were no remarkable findings on cystoscopic examination. Drip infusion pyelography and multidetector-row computed tomography demonstrated a tumor mass on the upper pole of the left kidney and atrophic right kidney. Systemic chemotherapy with CDDP, MTX and ADR was performed preoperatively. Then, hemi-left nephrectomy underwent with the diagnosis of renal pelvic tumor and renal tumor. The surgical specimen was pathologically diagnosed as transitional cell carcinoma of the renal pelvis and renal cell carcinoma of its upper pole. This is the 32nd case of simultaneous occurrence of renal cell carcinoma and transitional cell carcinoma in the same kidney in the Japanese literature.

Aged↗
PubMed2000

A cortical motor region that represents the cutaneous back muscles in the macaque monkey.

A cortical motor region that represented the cutaneous muscles on the back was identified on the medial wall of the frontal lobe in the macaque monkey. In this region, neurons responded to somatosensory stimuli such as light touch or squeezing of the back skin, and intracortical microstimulation elicited contraction of the back skin. Such a region was located primarily on the dorsal bank of the cingulate sulcus, corresponding to the dorsal cingulate motor area.

Animals↗