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Biomedical subjects

S Nakayama

Publications and source records attributed to S Nakayama.

At least 91 records · Page 5Linked to original sources
PubMed1998

[A case report of aortoesophageal fistula due to thoracoabdominal aortic aneurysm].

Aortoesophageal fistulas due to thoracic aneurysms are usually fatal, with few reported survivors. A 57-year-old man with aortoesophageal fistula due to thoracoabdominal aortic aneurysm underwent the graft replacement of thoracoabdominal aorta. In the postoperative course, prosthetic graft infection had occurred in the result of residual esophageal fistula. On the 32nd postoperative day (POD), a subtotal esophagectomy was performed and the esophagus was reconstructed by gastrointestinal interposition technique via a retrosternal route. Following the second operative procedure, inflammatory reactions had been improved with systemic administration of antibiotics and continuous irrigation of the infected cavity. On 77th POD, he was discharged.

Aortic Aneurysm, Abdominal↗
PubMed1998

Aortic valve replacement after previous coronary artery bypass grafting in a patient with antiphospholipid syndrome.

We report a 55-year-old female patient with antiphospholipid syndrome secondary to systemic lupus erythematosus. The patient had undergone coronary artery bypass grafting for myocardial infarction due to left main trunk stenosis at the age of 52. Subsequently, she developed aortic insufficiency and underwent aortic valve replacement without any hemodynamic or hemostatic problems. Both coronary and valve disease should be considered in patients with antiphospholipid syndrome secondary to systemic lupus erythematosus.

Antiphospholipid Syndrome↗
PubMed1998

[A case report of gastric perforation after coronary artery bypass grafting with right gastroepiploic artery].

A 71-year-old man, who had received coronary angioplasty to right coronary artery 1 year before, was admitted because of unstable angina. An urgent CABG was performed using the left internal thoracic artery and the right gastroepiploic artery. Coronary anastomosis was performed under ventricular fibrillation due to porcelain aorta. Seven days after surgery, abdominal pain was suddenly experienced. A chest X-P showed subphrenic free air. So an emergent laparotomy was performed, and a 2 x 2 cm gastric perforation was found on the anterior wall of the greater gastric curvature. Partial gastrectomy was performed. However, he unfortunately died on the 58th postoperative day for multiple organ failure. Pathological examination of the excised gastric wall revealed ischemic change, not ulcer. This gastric perforation was possibly caused by ischemia after harvesting the right gastroepiploic artery.

Aged↗
PubMed1998

Two-photon laser-scanning microscopy: tests of objective lenses and Ca2+ probes.

The characteristics of objective lenses and Ca2+-sensitive probes were examined for imaging with a two-photon laser-scanning microscope (TP-LSM). The brightness of the images of beads taken by different objectives greatly varied and depended predominantly on their numerical aperture (NA) and less on transmittance and chirping effects. Lateral and axial resolutions, dx and dz, defined as the half decay length of fluorescence intensity of the image of a spherical bead (0.3 m) were 0.12 and 0.42 microm (objective; 40x/0.75). They are far better than those of confocal microscopes (0.3 and 1.5 microm, respectively) measured similarly (Kuba et al., 1994). dx linearly increased with an increase in 1/NA, while dz linearly increased with an increase in n/(NA)2 (n, refractive index) except for an objective of large NA (1.3). The coverslip compensation of objective lenses greatly affected the shape of the X-Z scanned images of 5.0 microm beads as well as resolutions, indicating a large effect of spherical aberration. Two-photon excitation spectra of Ca2+-sensitive fluorescent probes, indo-1, fura-2 and Oregon Green BAPTA-1, lied in a wavelength range shorter than twice that activated by one-photon absorption, while emission spectra were unchanged. Three-dimensional images of a cultured hippocampal neurone loaded with Oregon Green BAPTA-1 showed fine structures of spines, dendrites and axons, while imaging with FM1-43 localized presynaptic boutons and demonstrated synaptic vesicle turnover. Dyes bleached little during the recording of 100 sectioned images. These characteristics of TP-LSM as well as its ability to image deeper tissues provide excellent means to study dynamic, spatial changes in intracellular substances and structures. To achieve the good performance of a TP-LSM, however, the relevant usage of appropriate objectives and fluorescent probes are required.

Animals↗
PubMed1998

Visualization of the Brassica self-incompatibility S-locus on identified oilseed rape chromosomes.

Seventy years after Karpechenko [15] first reported the accurate chromosome number of oilseed rape (Brassica napus L., 2n=38), we have developed a quantitative chromosome map of rape using computer imaging technology. The capacity to identify individual rape chromosomes will facilitate a wide range of genetic studies. Here we demonstrate the use of imaging methods in combination with fluorescence in situ hybridization to localize, on identified chromosomes, the single copy S-locus glycoprotein and S-locus-related genes involved in the self-incompatibility system of Brassica. These techniques have a broader application in plant genome research involving the mapping of single-copy genes and markers, irrespective of the plant species.

Brassica↗
PubMed1998

Classification and evolution of EF-hand proteins.

Forty-five distinct subfamilies of EF-hand proteins have been identified. They contain from two to eight EF-hands that are recognizable by amino acid sequence as being statistically similar to other EF-hand domains. All proteins within one subfamily are congruent to one another, i.e. the dendrogram computed from one of the EF-hand domains is similar, within statistical error, to the dendrogram computed from another(s) domain. Thirteen subfamilies--including Calmodulin, Troponin C, Essential light chain, Regulatory light chain--referred to collectively as CTER, are congruent with one another. They appear to have evolved from a single ur-domain by two cycles of gene duplication and fusion. The subfamilies of CTER subsequently evolved by gene duplications and speciations. The remaining 32 subfamilies do not show such general patterns of congruence; however, some--such as S100, intestinal calcium binding protein (calbindin 9 kd), and trichohylin--do not form congruent clusters of subfamilies. Nearly all of the domains 1, 3, 5, and 7 are most similar to other ODD domains. Correspondingly the EVEN numbered domains of all 45 subfamilies most closely resemble EVEN domains of other subfamilies. Many sequence and chemical characteristics do not show systemic trends by subfamily or species of host organisms; such homoplasy is widespread. Eighteen of the subfamilies are heterochimeric; in addition to multiple EF-hands they contain domains of other evolutionary origins.

Amino Acid Sequence↗
PubMed1998

A comparative study of a new, fully automated procedure and the standard mononuclear cell program using the Cobe Spectra for peripheral blood stem cell collection.

Recently, a completely automated procedure, the AutoPBSC program for the COBE Spectra cell separator, has been developed for peripheral blood stem cell harvest (PBSCH). We compared the performance of the AutoPBSC program with the standard mononuclear cell (MNC) program in the same patients and in a donor. Peripheral blood stem cells (PBSC) were collected from 3 patients or a donor alternately using the MNC program and the AutoPBSC program in a course of PBSC mobilization. Equal blood volume was processed from each patient (200 ml/kg) and a donor (150 ml/kg). We used a harvest volume of 3 ml and a chase volume of 7 ml in all AutoPBSC procedures. The procedure duration was almost equivalent for both programs. The volume of products was significantly lower in the AutoPBSC program (71 +/- 13 ml) than in the MNC program (183 +/- 30 ml). MNC yields were fewer, and total nucleated cell (TNC) and MNC collection efficiency was less for the AutoPBSC program compared to the MNC program. The CD34+ cell collection efficiency was less for the AutoPBSC program (26.5 +/- 13.7%, compared with 77.7 +/- 60.6%; p > 0.05). The contamination of platelets and red cells was significantly less in the AutoPBSC program than in the MNC program. In conclusion, we consider that the collection efficiency in the new program should be improved by modification of parameters because there exist great advantages to automated procedures.

Adult↗
PubMed1998

Vasoactive effects of cimicifugic acids C and D, and fukinolic acid in cimicifuga rhizome.

Vasoactive effects of cimicifugic acids A-E, fukinolic acid and fukiic acid isolated from Cimicifuga plants were investigated using rat aortic strips. Cimicifugic acid D and fukinolic acid at 3x10(-4) M caused a sustained, slowly developing relaxation of aortic strips precontracted with norepinephrine (NE) in preparations with or without endothelium. Cimicifugic acid C inversely caused a weak contraction. Cimicifugic acids A, B and E and fukiic acid showed no vasoactivity at 3x10(-4) M. Cimicifugic acids A-E and fukinolic acid are esters between cinnamic acids and the hydroxyl group of benzyltartaric acids. For the manifestation of vasoactivity in the rat aorta, it is concluded that in the cinnamic acid moiety, a caffeoyl group might be necessary for the relaxation activity, and the p-coumaroyl group causes contraction. Concentration response curves for the Ca2+-induced contracture of depolarized aortic strips with isotonic high K+ were not affected by cimicifugic acid D or fukinolic acid. The Ca2+-induced contraction of aortic strips, preincubated with 10(-6) M NE in the presence of 10(-6) M nicardipine and 0.01 mM EGTA in Ca2+-free solution, were inhibited by cimicifugic acid D and fukinolic acid. These results indicated that the inhibition by cimicifugic acid D and fukinolic acid of the NE-induced contraction of rat aorta are attributable to the suppression of Ca2+ influx from the extracellular space enhanced by NE.

Animals↗
PubMed1998

[A case of a lumbar spinal synovial cyst located on the midline].

We report a case of lumbar spinal synovial cyst located on the midline. A 72-year-old man was admitted to our hospital with the chief complaint of low back pain radiating to the left buttock and posterior thigh. An MR image revealed an extradural cystic lesion adjacent to the dorsal side of the dural sac at the L4-5 level. The cyst was remote from the facet joints and existed on the midline just in front of the L4 lamina. A CT scan showed a concave deformity of the ventral aspect of the L4 lamina because of compression by the cyst. The patient underwent L4 laminectomy and total removal of the cyst. The cyst was in contact with the anterior surface of the ligamentum flavum and it had no connection with the facet joint. In the histological examination, the cyst was multilobular and lined with synovial epithelium. Therefore the cyst was diagnosed as a synovial cyst. After the operation, the pain radiating to the buttock and thigh completely disappeared. Intraspinal synovial cysts are usually located in the lower lumbar spine and most of them are adjacent to the facet joint. The cysts that are located on the midline are very rare. We review previous reports and discuss clinical and pathological features of spinal synovial cysts.

Aged↗
PubMed1998

[Malignant lymphoma occurring in a patient with neurofibromatosis type 1 (von Recklinghausen disease)].

Malignant lymphoma developed in a 65-year-old man with type 1 neurofibromatosis (von Recklinghausen disease). The patient visited the hospital for evaluation of generalized lymphadenopathy. A physical examination discovered café au lait spots, neurofibromas, and generalized enlargement of the superficial lymph nodes. A computed tomogram demonstrated enlarged mediastinal and para-aortic lymph nodes in the abdomen. Biopsy specimens from the right side of the patient's neck were examined, and a diagnosis of non-Hodgkin's lymphoma (diffuse mixed type, T cell type) was made. Although the patient achieved a partial response with combination chemotherapy, he died of pneumonia. Cases of malignant lymphoma associated with type 1 neurofibromatosis are rare in the literature.

Aged↗
PubMed1998

[Successful removal of a left ventricular fibroma in a 10-year-old patient].

A 10-year-old girl with negative T wave in leads I, II, III, aVF, and V2-6 in the ECG was examined. The two-dimensional echocardiogram and the MRI revealed that she had a tumor in the free wall near the apex of the left ventricle. We removed the intramural fibroma (50 x 35 x 30 mm) of the left ventricle under cardiopulmonary bypass very carefully not to perforate the left ventricular cavity. After the removal, the defect was repaired by the sutures of the myocardial layers so that the volume inside the left ventricle could be kept and its shape could be maintained. She has been doing well without any trouble for 5 months after the operation.

Cardiac Surgical Procedures↗
PubMed1997

Consequences of metabolic inhibition in smooth muscle isolated from guinea-pig stomach.

1. In smooth muscle isolated from the guinea-pig stomach, cyanide (CN) and iodoacetic acid (IAA) were applied to block oxidative phosphorylation and glycolysis, respectively. Effects of IAA on generation of spontaneous mechanical and electrical activities were systematically investigated by comparing those of CN. Spontaneous activity ceased in 10-20 min during applications of 1 mM IAA. On the other hand, application of 1 mM CN also reduced the spontaneous activity, but never terminated it. In the presence of CN the negativity of the resting membrane potential was slightly reduced. 2. When spontaneous activity ceased with IAA, the resting membrane potential was not significantly affected. Also, before ceasing, the amplitude and duration of the spontaneous electrical activity were significantly reduced. The amplitude of the electrotonic potential was, however, not changed by IAA. Further, glibenclamide did not prevent the effects of IAA. These results suggest that, unlike cardiac muscle, activation of metabolism-dependent K+ channels in stomach smooth muscle does not seem to play a major role in reducing and terminating spontaneous activity during metabolic inhibition. 3. Carbachol-induced contraction transiently increased, and subsequently decreased gradually during application of IAA. 4. After 50 min application of IAA, when there was no spontaneous activity, the concentrations of phosphocreatine (PCr) and ATP measured with 31P nuclear magnetic resonance decreased to 60 and 80% of the control, respectively, while inorganic phosphate (Pi) concentration paradoxically fell to below detectable levels. During subsequent prolonged application of IAA, high-energy phosphates steadily decreased. On the other hand, after 50 min CN application, [PCr] and [ATP] decreased to approximately 30 and 80% of the control, respectively, while [Pi] increased by 2.6-fold. 5. In the presence of either CN or IAA, spontaneous mechanical and electrical activities were reduced or eliminated, although amounts of high-energy phosphates sufficient to contract smooth muscle remained. It can be postulated that some mechanism(s) related to energy metabolism, but not including ATP-sensitive K+ channels, plays an important role in generating spontaneous activity in guinea-pig stomach smooth muscle. During metabolic inhibition the energy metabolism-dependent mechanism(s) would preserve high-energy phosphates, and consequently cell viability, by stopping spontaneous activity.

Adenosine Triphosphate↗
PubMed1997

Ectopic expression of sex-peptide in a variety of tissues in Drosophila females using the P[GAL4] enhancer-trap system.

Sex-peptide (SP), which is secreted by the accessory gland of Drosophila males, is transferred to the female during copulation, thereby reducing her sexual appetite (receptivity to males) and stimulating ovulation/oviposition. SP is known to be taken up into the hemolymph of mated females, but it is not clear whether there are two separate target tissues, for behavioral changes and ovulation or only one target for both responses. We have employed the GAL4-UAS system to express SP transgene constructs, both in different tissues and in different cellular components of virgin females. A cytoplasmic form of SP lacking a signal sequence did not evoke any responses, even when expressed ubiquitously. In contrast, a membrane-bound form of SP induced typical post-mating behavior, indicating that SP must be outside the cell in order to exert its biological effects. A total of 204 randomly selected P[GAL4] enhancer-trap lines were screened for their ability to induce SP responses in combination with the membrane-bound SP expressed under GAL4 control. Thirty-three lines were associated with both behavioral change and stimulated ovulation. No line was associated with only one of the two responses, implying that the SP target(s) mediating the two responses are either identical, very closely located, or present in two distinct tissues with a common set of genetic determinants. Western blot analysis of head, thorax, and abdominal extracts revealed that the biological activity was correlated with expression in the head fraction.

Animals↗
PubMed1997

Simultaneous or delayed administration of hepatocyte growth factor equally represses the fibrotic changes in murine lung injury induced by bleomycin. A morphologic study.

Hepatocyte growth factor (HGF) is a humoral mediator of epithelial-mesenchymal interactions, acting on a variety of epithelial cells as mitogen, motogen, and morphogen. Exogenous HGF acts as a hepatotrophic factor and a renotrophic factor during experimental injury. To investigate whether HGF has a pulmotrophic function, human recombinant HGF was administered to C57BL/6 mice with severe lung injury by bleomycin (BLM). Low dose simultaneous and continuous administration of HGF (50 micrograms/mouse/7 d) with BLM (100 mg/mouse/7 d) repressed fibrotic morphological changes at 2 and 4 wk. Ashcroft score showed a significant difference in lung fibrosis with and without HGF at 4 wk (3.7 +/- 0.4 versus 4.9 +/- 0.3, p < 0.05). Furthermore, either simultaneous or delayed administration of high dose HGF (280 micrograms/mouse/14 d) equally repressed fibrotic changes by BLM when examined at 4 wk (Ashcroft score: 2.6 +/- 0.4 and 2.4 +/- 0.2 versus 4.1 +/- 0.2, p < 0.01). Hydroxyproline content in the lungs was significantly lower in mice with either simultaneous or delayed administration of high dose HGF as compared to those administered BLM alone (121.8 +/- 8.1% and 113.2 +/- 6.2% versus 162.7 +/- 4.6%, p < 0.001). These findings indicate that exogenous HGF acts as a pulmotrophic factor in vivo and prevents the progression of BLM-induced lung injury when administered in either a simultaneous or delayed fashion. HGF may be a potent candidate to prevent or treat lung fibrosis.

Animals↗
PubMed1997

[A 64-year-old woman with severe headache and progressive disturbance of consciousness].

We report a 64-year-old woman who developed nausea, headache, and consciousness disturbance. She was well until four years before the onset of her neurologic illness when (April of 1990 at her 59 years of the age) she was found to have an early cancer in her anterior wall of the lower stomach. Subtotal gastrectomy was performed and the operative result was reported as curative. Four years after the surgery (December of 1994 at her 64 years of the age), she noted suboccipital headache and nausea which had become progressively worse and she was admitted to our service on May 24, 1995. On admission, she appeared chronically ill but general physical examination was unremarkable with normal vital signs. Neurologically she was alert and not demented, and the higher cerebral functions were intact. Cranial nerves were also unremarkable. She was able to walk in tandem and on heels. No motor weakness or ataxia was noted. Deep tendon reflexes were moderately increased, however, no Babinski sign was noted. Although she had headache, no meningeal signs were seen. Slight superficial and vibratory sensory loss was noted in both feet. Routine blood work was again unremarkable except for slight increase in CEA to 8.3 ng/dl (N < 5 ng/dl). The opening pressure of lumbar CSF was 180 mm H2O and the CSF contained 39 cells/microliter, 79 mg of protein, and 10 mg/dl of glucose. Approximately half of the cells were atypical malignant cells. Plain CT was unremarkable, however, tentorial border showed enhancement after contrast infusion. FGS showed no malignant tumors in the stomach. She was treated with intravenous glycerol and whole brain radiation, however, she continued to complain of severe headache, and her sensorium started to be disturbed one month after the admission. Follow-up cranial CT scan revealed enlargement of the lateral and the third ventricles. Her consciousness progressively deteriorated and she became comatose three months after the admission. Repeated cranial CT scan showed enlargement of the ventricles, but no mass lesions were seen within the brain. She developed respiratory arrest on September 25 of the same year. She was discussed in a neurological CPC and the chief discussant arrived at the conclusion that the patient had a gastric cancer with meningeal seeding developing meningeal carcinomatosis. The cause of deep coma was ascribed to damage of cerebral cortical areas secondary to metastatic carcinoma cells and fibrinous materials in the surface of the brain. Postmortem examination revealed thickening and clouding of leptomeninges of the cerebral convexity. On histologic observation, patchy areas of fibrous thickening were seen in the cerebral leptomeninges; in such areas, adenocarcinomatous cells were seen scattered. The basal meninges were free of carcinoma cells, however, leptomeninges of the cerebellum and brain stem tegmentum contained scattered carcinoma cells. The lateral and the third ventricles were enlarged, however, insides of the brain were free of pathologies; the ependymal layer were intact. In the stomach no carcinoma cells were remaining. Pneumonic changes were seen in the right upper and the left lower lobes which appeared to be the direct cause of her death. No evidence of tentorial herniation was noted. The cause of her deep coma was not clearly determined, however, combination of hydrocephalus and cortical malfunction due to leptomeningeal carcinoma cell infiltration and fibrinous material accumulation appeared to have played a role.

Adenocarcinoma↗