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Biomedical subjects

H Shinohara

Publications and source records attributed to H Shinohara.

At least 55 records · Page 3Linked to original sources
PubMed2001

Complications associated with pulmonary resection in lung cancer patients on dialysis.

BACKGROUND: There are few studies available investigating the perioperative problems experienced by lung cancer patients on dialysis undergoing pulmonary resection. METHODS: A retrospective review of 7 patients on dialysis undergoing pulmonary resection for lung cancer was performed. RESULTS: The patient population consisted of 7 men, with a mean age of 59.9 years. The underlying kidney disease was glomerulonephritis in 5 patients and nephrosclerosis in 2. The mean levels of blood urea nitrogen and serum creatinine were 70.7 mg/dL and 9.4 mg/dL, respectively. Histologic diagnoses were adenocarcinoma in 2 patients and squamous cell carcinoma in 5. Standard lobectomy with lymph node dissection was performed in all cases. There was one operation related death due to pulmonary edema and subsequent development of pneumonia. There were two cases of sputum retention and four of hyperkalemia. One patient died of cerebral bleeding that occurred during dialysis 2 months postoperatively. CONCLUSIONS: In patients on dialysis who undergo pulmonary resection, there is a high incidence of pulmonary complications, in addition to hyperkalemia, hemodynamic instability, and a tendency for postoperative dialysis-associated bleeding.

Adenocarcinoma↗
PubMed2001

Intrafullerene electron transfers in Sm-containing metallofullerenes: Sm@C2n (74 < or = 2n < or = 84).

The electronic properties of Sm-containing metallofullerenes, Sm@C74, Sm@C76 (I, II), Sm@C78, Sm@C80, Sm@C82 (I, II, III) and Sm@C84 (I, II, III), are characterized by UV-Vis-NIR absorption spectroscopy and electron energy-loss spectroscopy (EELS). The UV-Vis-NIR absorption spectra of Sm@C74, Sm@C80, Sm@C82 (I, II, III) and Sm@C84 (I, II) are quite similar to those of the corresponding Ca, Sr, Ba, Eu, Tm, Yb-based metallofullerenes. In contrast, the absorption spectra of Sm@C76 (I, II), Sm@C78 and Sm@C84(III) show a novel feature: the onset for Sm@C78 is observed approximately 2600 nm, which corresponds to a small band gap (approximately 0.5 eV). Furthermore, the oxidation states of Sm atom in the various fullerene cages are investigated by EELS, which reveals that the Sm atom takes +2 oxidation state in the fullerene cages. A probable rationale for the tendency to have the Sm2+ state is presented based on a simple thermochemical cycle model.

Carbon↗
PubMed2001

Selective localization of G protein gamma5 subunit in the subventricular zone of the lateral ventricle and rostral migratory stream of the adult rat brain.

G proteins play important roles in transmembrane signal transduction, and various isoforms of each subunit, alpha, beta and gamma, are highly expressed in the brain. The Ggamma5 subunit is a minor isoform in the adult brain, but we have previously shown it to be highly expressed in the proliferative region of the ventricular zone in the rat embryonic brain. We show here that Ggamma5 is also selectively localized in a proliferative region in the adult rat brain, including the subventricular zone of the lateral ventricle and rostral migratory stream. The Galphai2 subunit colocalized with Ggamma5 in these regions, the two subunits being present in neuronal precursors and ependymal cells but not in proliferating astrocytes. In addition, intense staining of Ggamma5 was seen in axons of the olfactory neurons, which are known to regenerate. These results suggest specific roles for Ggamma5 in precursor cells during neurogenesis so that this isoform might be a useful biological marker.

Animals↗
PubMed2001

Enhanced production of macrophage inflammatory protein 2 (MIP-2) by in vitro and in vivo infections with encephalomyocarditis virus and modulation of myocarditis with an antibody against MIP-2.

Interleukin-8 (IL-8) is a chemotactic cytokine for neutrophils and lymphocytes. Macrophage inflammatory protein 2 (MIP-2) is a murine counterpart of IL-8. The present study was performed to determine whether MIP-2 aggravates murine myocarditis. We examined (i) the MIP-2-producing activity of encephalomyocarditis (EMC) virus-infected cultured macrophages, (ii) serial plasma MIP-2 levels in EMC virus-induced mice by enzyme-linked immunosorbent assay, and (iii) the effects of antimouse MIP-2 monoclonal antibody (MAb) in vivo upon myocarditis. The production of MIP-2 increased in an infection dose- and time-dependent manner in virus-infected RAW 264. 7 macrophages. Five-week-old C(3)H/He mice were inoculated with EMC virus. Plasma MIP-2 levels were significantly elevated in mice on days 7 and 14 postinfection. Mice were injected subcutaneously with anti-MIP-2 MAb at 10 microg/day (group 2) or 100 microg/day (group 3) on days 0 to 5 and were observed until day 21. Uninfected control mice (group 1) were prepared. The survival rate was higher in the anti-MIP-2-treated group (group 3), but not in group 2, than in the control group. Histopathological analysis revealed that cellular infiltration and myocardial necrosis with macrophage and T-cell accumulation were less prominent in the anti-MIP-2 MAb-treated group, but not in group 2, compared to the level in the controls. MIP-2 is an important naturally occurring inflammatory cytokine in myocarditis, and anti-MIP-2 MAb treatment may prevent the inflammatory response.

Animals↗
PubMed2001

A case of thyrotoxicosis with pancytopenia.

We report a 49-year-old man with primary hyperthyroidism who presented with pancytopenia. The patient presented with leg edema, sinus tachycardia, cardiomegaly, and pleural effusions, all from congestive heart failure. Laboratory data showed pancytopenia and primary hyperthyroidism; echocardiogram showed diffuse hyperkinesis of the left ventricular wall and right ventricular overloading. The bone marrow was moderately hypercellular and compatible with arrested hematopoiesis. Pancytopenia and heart failure improved after administration of methimazole and diuretics. However, high levels of thyroid hormone recurred with pancytopenia 4 months after admission. Therefore, subtotal thyroidectomy was performed, and the levels of thyroid hormones and peripheral blood cell counts have remained normal. Pancytopenia may be caused by hyperthyroidism.

Antithyroid Agents↗
PubMed2001

Fullerenes in medicinal chemistry and their biological applications.

The isolation and preparation ten years ago of the fullerenes in bulk quantities, sparked off a truly remarkable interdisciplinary research activity, encompassing diverse fields of chemistry, physics, materials science and medicinal chemistry. Pharmaceutical and biological studies have revealed that fullerene-based compounds exhibit various types of biological activity either in vitro or in vivo and are discussed in this review.

Animals↗
PubMed2001

The anatomy of the lacrimal portion of the orbicularis oculi muscle (tensor tarsi or Horner's muscle).

Horner's muscle (the palpebral part of the orbicularis oculi muscle) has a fan-shaped origin in the lacrimal bone. Its muscle fibers are oriented from 160 to 210 degrees relative to the ear-eye plane and converge towards the medial palpebral commissure. Then the muscle divides into superior and inferior bundles of fibers. Some of the lower fibers participate in the formation of the superior bundle and some of the higher fibers participate in the formation of the inferior bundle and, thus, some of Horner's muscle is twisted. Each bundle courses laterally to the lateral palpebral commissure and has three insertions. The first insertion is located at the medial margin of the tarsi. The second insertion is into the subcutaneous tissue along the palpebral margins. Minute fascicles of Horner's muscle are fastened to the palpebral margins. The third insertions are into the lateral palpebral ligament and subcutaneous connective tissue of the lateral commissure. Serial histological sections of a fetus at 14 to 16 weeks gestation revealed that the extent of the envelope formed by Horner's muscle around the lacrimal canaliculus decreases gradually from the lacrimal papilla to the lacrimal sac. The various observations suggest the following roles for Horner's muscle: (1) it closes the medial canthus of the eye and closes the lacrimal punctum; (2) it pulls the tarsus medially; (3) it tautens the palpebral margins and presses against the eyeball; and (4) it squeezes the lacrimal canaliculus with a decreasing gradient of pressure from the lacrimal papilla to the lacrimal sac. These actions are likely to be important for the flow of lacrimal fluid in the lateral to medial direction on the eyeball, for maintenance of the thickness of tear film over the cornea, for opening and closing of the lacrimal punctum, and for passage of the lacrimal fluid from the canaliculus to the sac. Horner's muscle appears, thus, to be a muscle of prime importance in all phases of the flow of lacrimal fluid.

Aged↗
PubMed2001

[Clinical significance of coronary flow reserve in hypertrophied heart: comparison with Doppler index, hemodynamics and plasma natriuretic peptide concentrations].

OBJECTIVES: The relationship was investigated between coronary flow reserve and Doppler echocardiographic parameters, hemodynamic parameters and plasma natriuretic peptide concentrations in the hypertrophied heart. METHODS: The subjects were 19 patients with hypertrophied heart due to various etiologies and no significant coronary artery stenosis. All patients were in sinus rhythm. The left ventricular wall thickness, the E/A ratio in transmitral flow velocity pattern and the Doppler index were determined by Doppler echocardiography, and the plasma atrial and brain natriuretic peptide concentrations were measured. At cardiac catheterization, pulmonary capillary wedge pressure and left ventricular end-diastolic pressure were measured, and the coronary flow reserve was obtained by injecting intracoronary adenosine triphosphate into the left anterior descending artery using a Doppler guidewire. RESULTS: Coronary flow reserve in the patients was significantly lower than in 11 normal control subjects (2.50 +/- 0.76 vs 3.90 +/- 0.64, p < 0.001). There were no significant correlations between coronary flow reserve and the left ventricular wall thickness or the E/A ratio. The mean value of the Doppler index in the patients was 0.48 +/- 0.10 and there was a significant negative correlation between coronary flow reserve and the Doppler index (r = -0.73, p < 0.001). The correlation between coronary flow reserve and left ventricular end-diastolic pressure was not significant, but there was a significant negative correlation between coronary flow reserve and pulmonary capillary wedge pressure (r = -0.64, p < 0.01). There were significant negative correlations between coronary flow reserve and atrial (r = -0.62, p < 0.01), or brain natriuretic peptide concentrations (r = -0.56, p < 0.05). CONCLUSIONS: Coronary flow reserve may reflect overall cardiac performance evaluated by the Doppler index and plasma natriuretic peptide concentrations in the hypertrophied heart, and the measurement of coronary flow reserve may be useful for evaluating disease severity in patients with hypertrophied heart.

Aged↗
PubMed2001

[A case of stage IV gastric cancer with multiple liver metastases and carcinomatous ascites responding to TS-1 for six months before progression].

We report the case of a 72-year-old male with Stage IV gastric cancer accompanied by multiple liver metastases and carcinomatous ascites which responded to chemotherapy using TS-1. Treatment of the patient with daily oral administration of 120 mg TS-1 for 4 weeks resulted in complete regression of the liver metastases and ascites, as well as a 35% reduction in the size of the primary lesion. After 2 cycles, the primary tumor size was reduced to 55% and serum CA19-9 and CA125 levels were decreased to the normal ranges. This regimen was effective without any adverse effects, and improved the patient's QOL, for 6 months before progression of liver lesions. The patient received chemotherapy at our outpatient clinic for 10 months after the first treatment, after which he died of peritonitis carcinomatosa. The current case suggests that TS-1 may have a potent therapeutic efficacy in advanced gastric cancer patients.

Aged↗
PubMed2001

Transforming growth factor-alpha delays gastric emptying and small intestinal transit in suckling rats.

Transforming growth factor-alpha (TGF-alpha) is a biologically potent polypeptide detected in the gastrointestinal tract in suckling rats. The major goal of the present study was to test the hypothesis that the administration of TGF-alpha affects gastric emptying and small intestinal transit in suckling rats. Suckling (12-day-old) rats fasted 16 h received rat TGF-alpha subcutaneously (s.c.) or orogastrically in varying doses (0, 0.5, 1.0 microg/rat in 0.1% BSA). Control animals received 0.1% BSA only. Poly R-478 dye was used as a motility marker. Rats were decapitated 45 min after marker administration and the amount of dye in the stomach and the small intestine was measured by spectrophotometry. Subcutaneous administration of TGF-alpha significantly delayed stomach evacuation. In controls, the stomach contained 21.4 +/- 1.4% (mean +/- s(x)) of the Poly R-478 marker, whereas in TGF-alpha treated rats the stomach contained 37.2 +/- 2.8% of the total Poly R-478 dye given to animals. The delaying effect of TGF-alpha was time- and dose-dependent. Small intestinal transit was also significantly delayed. The proximal jejunum of TGF-alpha treated rats contained a 1.4-fold higher amount of marker in comparison with control rats. Orogastrically administered rTGF-alpha did not affect gastric emptying or intestinal transit. In conclusion, s.c. administration of rat TGF-alpha significantly delayed the gastrointestinal motility in vivo in suckling rats.

Analysis of Variance↗
PubMed2001

[A successful surgical case of incomplete atrioventricular septal defect with pulmonary dysfunction].

A 58-year-old female with incomplete atrioventricular septal defect was treated successfully with surgery. We repaired the defect by closure of atrioventricular septal defect, suture of cleft and tricuspid valve annuloplasty. We adopted method of minimally invasive cardiac surgery (MICS) expecting to preserve pulmonary function and to perform tracheostomy on early stage. After the operation she recovered with no major complications. It is suggested that MICS is effective method for patients with pulmonary dysfunction.

Cardiac Surgical Procedures↗
PubMed2000

Element-selective single atom imaging.

Electron energy-loss spectroscopy (EELS) is widely used to identify elemental compositions of materials studied by microscopy. We demonstrate that the sensitivity and spatial resolution of EELS can be extended to the single-atom limit. A chemical map for gadolinium (Gd) clearly reveals the distribution of Gd atoms inside a single chain of metallofullerene molecules (Gd@C82) generated within a single-wall carbon nanotube. This characterization technique thus provides the "eyes" to see and identify individual atoms in nanostructures. It is likely to find broad application in nanoscale science and technology research.

Journal Article↗
PubMed2000

One-dimensional metallofullerene crystal generated inside single-walled carbon nanotubes.

Electron microscope imaging for gadolinium metallofullerenes encapsulating in single-wall carbon nanotubes [(Gd@C82)n@SWNTs] identifies the single Gd atom encaged in each. The intermolecular distance between Gd@C82 is extremely regular, regarding the chains of Gd@C82 as novel one-dimensional crystals. Chemical state analysis of Gd atoms suggests evidence for charge transfer from Gd to either a fullerene cage or a nanotube. The slopes of the temperature dependence of electric resistance for the mat-like films of (Gd@C82)n@SWNTs and (C60)n@SWNTs are much steeper than that for empty SWNTs, suggesting the electron scattering due to the electrostatic potential from inside fullerenes playing an important role.

Journal Article↗
PubMed2000

Dissociation and recombination between ligands and heme in a CO-sensing transcriptional activator CooA. A flash photolysis study.

CooA from Rhodospirillum rubrum is a transcriptional activator in which a heme prosthetic group acts as a CO sensor and regulates the activity of the protein. In this study, the electronic relaxation of the heme, and the concurrent recombination between ligands and the heme at approximately 280 K were examined in an effort to understand the environment around the heme and the dynamics of the ligands. Upon photoexcitation of the reduced CooA at 400 nm, electronic relaxation of the heme occurred with time constants of 0.8 and 1.7 ps. The ligand rebinding was substantially completed with a time constant of 6.5 ps, followed by a slow relaxation process with a time constant of 173 ps. In the case of CO-bound CooA, relaxation of the excited heme occurred with two time constants, 1.1 and 2.4 ps, which were largely similar to those with reduced CooA. The subsequent CO recombination process was remarkably fast compared with that of other CO-bound heme proteins. It was well described as a biphasic geminate recombination process with time constants of 78 ps (60%) and 386 ps (30%). About 10% of the excited heme remained unligated at 1.9 ns. The dynamics of rebinding of CO thus will help us to understand how the physiologically relevant diatomic molecule approaches the heme binding site in CooA with picosecond resolution.

Bacterial Proteins↗
PubMed2000

Organic chemistry with heterofullerenes: photosensitized oxygenation of alkenes

Heterofullerenes C(59)HN and (C(59)N)(2) sensitize the reaction of olefins with molecular oxygen under photolytic conditions. 2-Methyl-2-butene and alpha-terpinene undergo ene and Diels-Alder photooxygenation reactions, respectively, even in the presence of minute amounts of azafullerenes to produce the corresponding peroxides.

Journal Article↗