Left ventricular assist systems as a bridge to heart transplantation: the role and the strategy in Japan.
Explore the source record for details and available documents.
Adolescent↗
Biomedical subjects
T Yamaguchi
Publications and source records attributed to T Yamaguchi.
Role of endothelial apoptosis in delayed xenograft rejection in pig-to-baboon cardiac transplantation.
Explore the source record for details and available documents.
Animals↗
Analysis of red/green color discrimination in subjects with a single X-linked photopigment gene.
Many subjects despite having only a single X-linked pigment gene (single-L/M-gene subjects) are able to make chromatic discriminations by Rayleigh matching, especially when large fields are used. We used a combination of psychophysics (Rayleigh match), electroretinograms (ERG), and molecular genetic techniques to rule out several possible explanations of this phenomenon. Use of rods for chromatic discrimination was unlikely since strong adapting fields were employed and the large-field match results were not consistent with rod participation. A putative mid- to long-wavelength photopigment that escapes detection by current molecular genetic analysis was ruled out by finding only a single L/M photopigment in flicker ERGs from 16 single-L/M-gene subjects. Large-field match results were not consistent with participation of S cones. Amino acid sequence polymorphisms in the S-pigment gene that might have shifted the S cone spectrum towards longer wavelengths were not found on sequencing. The mechanism of chromatic discrimination in the presence of a single photopigment therefore remains unknown. Further possible explanations such as variations in cone pigment density and retinal inhomogeneities are discussed.
Adaptation, Ocular↗
Itch-associated response induced by intradermal serotonin through 5-HT2 receptors in mice.
Serotonin (5-HT) is pruritogenic in humans and suggested to be involved in some pruritic diseases. Our experiments were carried out to determine whether an intradermal injection of 5-HT would elicit itch-associated response in mice and to elucidate the 5-HT receptor subtypes involved in this 5-HT action. 5-HT (14.1-235 nmol site(-1)) injected intradermally into the rostral back elicited scratching of the injected site, with bell-shaped dose-response relationship. The scratching induced by 5-HT (100 nmol site(-1), peak effective dose) was suppressed by capsaicin (repeated administration) and the opioid antagonist naloxone, features being similar to human itching. Scratching was also elicited by the 5-HT2 receptor agonist alpha-methylserotonin, but not by the 5-HT1A receptor agonist R(+)-8-hydroxy-N,N-dipropyl-2-aminotetralin nor the 5-HT3 receptor agonists 2-methylserotonin and 1-phenylbiganide. Scratching induced by 5-HT and alpha-methylserotonin was inhibited by peroral pretreatment with 5-HT1/2 receptor antagonists methysergide and cyproheptadine. 5-HT-induced scratching was also inhibited by intradermal injection of methysergide. Peroral pretreatment with 5-HT3 receptor antagonists ondansetron and 3-tropanyl-3, 5-dichrobenzoate did not significantly suppress 5-HT-induced scratching. The results suggest that scratching induced by intradermal injection of 5-HT is itch-associated response. The 5-HT action may be mediated at least partly by cutaneous 5-HT2 receptors.
Analysis of Variance↗
Molecular weight independence of the effect of additive hyaluronic acid on the lubricating characteristics in synovial joints with experimental deterioration.
OBJECTIVE: To assess the molecular weight dependence of the lubricating characteristics of additive hyaluronic acid in animal joints with experimental deterioration. DESIGN: An experimental study in rabbits stifles in vitro. BACKGROUND: Hyaluronic acid is used as a drug for osteoarthritis. However, the molecular weight dependence of the effect of hyaluronic acid has been unclear. METHODS: Using a robotic arm under force-control, frictional coefficients were measured in fourteen rabbit stifles. The experimental conditions examined were: (1) intact joint surfaces; (2) after the joint surfaces were washed with physiological saline; (3) after the addition of 1% hyaluronic acid solution with a molecular weight of one million daltons and two million daltons, respectively. RESULTS: The increased frictional coefficient produced by washing with saline was decreased significantly by the addition of hyaluronic acid to the joint surfaces. This effect was observed regardless of the molecular weight of the hyaluronic acid. CONCLUSION: The lubricating characteristics of hyaluronic acid in synovial joints do not change with molecular weight. RELEVANCE: Hyaluronic acid solution is used clinically for the treatment of osteoarthritis. In the present study, the molecular weight dependency of the lubricating characteristics of hyaluronic acid was tested using the friction in synovial joints.
Animals↗
Brain-derived neurotrophic factor regulates the expression of AMPA receptor proteins in neocortical neurons.
The role of the neurotrophins; nerve growth factor, brain-derived neurotrophic factor, neurotrophin-3 and neurotrophin-4/5, in synaptic development and plasticity has been extensively investigated. The neurotrophins regulate synaptic transmission as well as neural development in the brain. However, the mechanisms underlying these processes are unknown. In this study we show that brain-derived neurotrophic factor triggers an increase in alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-type glutamate receptor (GluR) proteins without significant changes in their messenger RNA levels. Brain-derived neurotrophic factor treatment specifically increased the protein levels of GluR1 (193+/-22%) and GluR2/3 (182+/-11%) in cultured rat neocortical neurons. In contrast, nerve growth factor and neurotrophin-3 failed to alter the protein levels of these neurons, and brain-derived neurotrophic factor effects on N-methyl-D-aspartate-type glutamate receptors were either modest or negligible. Immunocytochemical studies indicated that the increase in AMPA receptor proteins reflects the induction of their neuronal expression, but not selective neuronal survival. In agreement with these results, cortical neurons from brain-derived neurotrophic factor-knockout mice exhibited a reduction in AMPA receptor proteins in the cytoskeletal fraction containing postsynaptic proteins. Thus, the neurotrophin plays a crucial role in modulating the expression of AMPA receptors presumably at translational or post-translation levels and is implicated in synaptic development and plasticity.
Animals↗
Effects of adjunctive balloon angioplasty after intravascular ultrasound-guided optimal directional coronary atherectomy: the result of Adjunctive Balloon Angioplasty After Coronary Atherectomy Study (ABACAS).
OBJECTIVES: This study was conducted to evaluate: 1) the effect of adjunctive percutaneous transluminal coronary angioplasty (PTCA) after directional coronary atherectomy (DCA) compared with stand-alone DCA, and 2) the outcome of intravascular ultrasound (IVUS)-guided aggressive DCA. BACKGROUND: It has been shown that optimal angiographic results after coronary interventions are associated with a lower incidence ofrestenosis. Adjunctive PTCA after DCA improves the acute angiographic outcome; however, long-term benefits of adjunctive PTCA have not been established. METHODS: Out of 225 patients who underwent IVUS-guided DCA, angiographically optimal debulking was achieved in 214 patients, then theywere randomized to either no further treatment or to added PTCA. RESULTS: Postprocedural quantitative angiographic analysis demonstrated an improved minimum luminal diameter (2.88 +/- 0.48 vs. 2.6 +/- 0.51 mm; p = 0.006) and a less residual stenosis (10.8% vs.15%; p = 0.009) in the adjunctive PTCA group. Quantitative ultrasound analysis showed a larger minimum luminal diameter (3.26 +/- 0.48 vs. 3.04 +/- 0.5 mm; p < 0.001) and lower residual plaque mass in the adjunctive PTCA group (42.6% vs. 45.6%; p < 0.001). Despite the improved acute findings in the adjunctive PTCA group, six-month angiographic and clinical results were not different. The restenosis rate (adjunctive PTCA 23.6%, DCA alone 19.6%; p = ns) and target lesion revascularization rate (20.6% vs. 15.2%; p = ns) did not differ between the groups. CONCLUSIONS: With IVUS guidance, aggressive DCA can safely achieve optimal angiographic results with low residual plaque mass, and this was associated with a low restenosis rate. Although adjunctive PTCA after optimal DCA improved the acute quantitative coronary angiography and quantitative coronary ultrasonography outcomes, its benefit was not maintained at six months.
Aged↗
Expression of Th1 and Th2 cytokine mRNAs in freshly isolated peripheral blood mononuclear cells of a patient with cutaneous paragonimiasis.
Using semiquantitative reverse transcriptase polymerase chain reaction, we examined the levels of various cytokine mRNAs of freshly isolated peripheral blood mononuclear cells (PBMCs) from a cutaneous paragonimiasis patient in the course of successful treatment with praziquantel administration. The pre-treatment levels of Th2 cytokines such as interleukin (IL)-4, IL-5, IL-10 and IL-13 mRNAs in PBMCs of the patient were much higher than those of healthy controls. The levels of IL-4, IL-5 and IL-13 mRNAs slightly elevated on day 2 of the treatment and then declined to the control levels on day 25. The IL-10 mRNA level rapidly decreased after the chemotherapy. In contrast, the mRNA levels of interferon (IFN)-gamma, a Th1 cytokine, remained in the control levels during the course. Peripheral eosinophil counts and levels of total IgE and eosinophil cationic protein in the sera correlated well with the levels of these Th2 cytokine mRNAs. These results suggested the major role of Th2 cytokines in clinical manifestation of human helminthic infection.
Adult↗
Closely linked polymorphic markers for determining the autosomal dominant allele (Cy) in rat polycystic kidney disease.
The Han:SPRD strain is an SD-background strain known to be a model of polycystic kidney disease (PKD) expressed through an autosomal dominant gene (Cy). However, different genotypes of this strain cannot be identified in the neonatal period. First, to establish an accurate method of determining the genotypes (Cy/Cy, Cy/+, +/+) which cause different disease progressions, we used polymorphic markers on rat chromosome 5. PCR products of tissue DNA templated with D5Rat9 showed distinct patterns on electrophoresis indicating three genotypes. Second, to determine whether the same locus plays a major role in expressing PKD, we performed linkage analyses in a [BN x (BN x Han:SPRD)F1] backcross. Cy/Cy and Cy/+ also caused PKD in a BN background. In this backcross, we discovered that D5Rat11 is located closer to the Cy locus than D5Mgh10, which is regarded as one of the closest loci. We conclude that D5Rat9 and D5Rat11 are useful markers for determining the presence of the Cy allele, which is regarded as the gene responsible for PKD.
Alleles↗
Total gastrectomy with simultaneous pancreaticosplenectomy or splenectomy in patients with advanced gastric carcinoma.
A splenectomy or distal pancreaticosplenectomy is often performed simultaneously with total gastrectomy in the treatment of gastric carcinoma to facilitate dissection of the lymph nodes around the splenic artery and splenic hilus. However, the negative impact of splenectomy and pancreaticosplenectomy has also been reported. A retrospective analysis was performed to evaluate the outcomes of distal pancreaticosplenectomy and total gastrectomy, splenectomy and total gastrectomy, and gastrectomy alone in the patients with advanced gastric carcinoma without distant metastasis. Prognostic factors were examined. No significant differences existed in 5-year survival in the patients who underwent gastrectomy with splenectomy, gastrectomy with distal pancreaticosplenectomy, or gastrectomy alone. Neither splenectomy, nor distal pancreaticosplenectomy were prognostic factors. However, distal pancreaticosplenectomy was an independent predictor of pancreatic fistula. In conclusion, the addition of distal pancreaticosplenectomy or splenectomy to total gastrectomy for gastric cancer increases the risk of severe complications, but does not improve survival.
Aged↗
Chromosomal aberrations in human hepatocellular carcinomas associated with hepatitis C virus infection detected by comparative genomic hybridization.
Thirty-five hepatocellular carcinomas (HCCs) associated with hepatitis C virus (HCV) were analysed by comparative genomic hybridization (CGH), to screen for changes in copy-number of DNA sequences. Chromosomal losses were noted in 1p34-36 (37%), 4q12-21 (48%), 5q13-21 (35%), 6q13-16 (23%), 8p21-23 (28%), 13q (20%), 16q (33%) and 17p13 (37%). Gains were noted in 1q (46%), 6p (20%), 8q21-24 (31%) and 17q (43%). High level gains indicative of gene amplifications were found in 7q31 (3%), 11q13 (3%), 14q12 (6%) and 17q12 (3%); amplification at 14q12 may be characteristic for HCCs. No significant difference in chromosomal aberrations was noted between carcinomas associated with HCV-infection in our study and those reported earlier in HCCs infected with hepatitis B virus (HBV), indicating that both HBV- and HCV-related carcinomas may progress through a similar cascade of molecular events.
Carcinoma, Hepatocellular↗
Osteitis fibrosa cystica generalizata with adult T-cell leukaemia: a case report.
We report on a 62-year-old female initially suffering from extreme pain in both her lower extremities. Plain radiographs revealed multiple osteolytic lesions. Laboratory analyses indicated high levels of serum calcium and parathyroid hormone related protein (PTHrP) and detected HTLV-1 antibody. Histological examination of biopsied specimens which were obtained from osteolytic lesions indicated osteitis fibrosa cystica (OFC) without tumour cells. After the initial biopsy, a subcutaneous mass developed in the left thigh. Microsections of the biopsied mass disclosed adult T-cell leukaemia (ATL) neoplastic cells. Immunohistochemical findings revealed that PTHrP secreted from ATL neoplastic cells induced the OFC.
Female↗
No survival benefit from combined pancreaticosplenectomy and total gastrectomy for gastric cancer.
BACKGROUND: It remains unknown whether extended surgery improves the survival rate of patients with gastric cancer. This study was a review of combined pancreaticosplenectomy with total gastrectomy for gastric cancer. METHODS: The clinicopathological details of 190 patients who underwent combined pancreaticosplenectomy with total gastrectomy between 1969 and 1996 were compared retrospectively with those of 206 patients who underwent total gastrectomy with splenectomy alone. RESULTS: There was no statistical difference in the survival rate when pancreaticosplenectomy was added to total gastrectomy. The mortality rate was similar, but the morbidity rate was higher in patients who had pancreaticosplenectomy. Six patients who had direct pancreatic invasion and two thought to have involved lymph nodes along the splenic artery survived for more than 5 years after operation. In the latter group, the metastatic lymph nodes along the splenic artery could have been resected without pancreatectomy. CONCLUSION: Since a combined pancreaticosplenectomy adds no survival advantage to total gastrectomy for gastric cancer, this procedure should no longer be regarded as routine.
Female↗
Selective effects of lomerizine, a novel diphenylmethylpiperazine Ca2+ channel blocker, on cerebral blood flow in rats and dogs.
1. In the present study we examined the effects of a new Ca2+ channel blocker (lomerizine), an antimigraine drug, on cerebral cortical blood flow (CBF) in anaesthetized rats (laser Doppler flowmetry) and on vertebral blood flow in anaesthetized beagle dogs (electromagnetic flowmeter). 2. Lomerizine (1.25-10 mg/kg, p.o.) dose-dependently increased CBF in rats without affecting blood pressure (BP) or heart rate (HR). 3. The plasma concentration of lomerizine (free base) in anaesthetized rats at 30 and 60 min after the initial administration of 5 mg/kg, p.o., time at which there was a significant increase in CBF, was similar to that reported in healthy subjects receiving lomerizine at 10 mg (2 x 5 mg)/day, p.o., a dose that significantly reduces the frequency and mean duration of headache attacks. 4. Flunarizine (10 mg/kg, p.o.) did not increase CBF significantly. Flunarizine (20 mg/kg, p.o.) did not increase CBF, but did decrease BP 30-120 min after its administration. 5. Lomerizine (2.5 and 5 mg/kg, intraduodenally) dose-dependently increased vertebral blood flow in dogs without significantly changing BP or HR. With 10 mg/kg intraduodenal lomerazine, vertebral blood flow remained elevated from 20 to 240 min after administration and BP was decreased from 20 to 120 min. 6. Thus, lomerizine had a greater effect on CBF than on BP and HR and, therefore, it may be clinically effective in conditions associated with circulatory disturbances in the brain, such as migraine, without producing systemic effects (e.g. hypotension) generally seen with other Ca2+ channel blockers.
Animals↗
Increased mucosal production of granulocyte colony-stimulating factor is related to a delay in neutrophil apoptosis in Inflammatory Bowel disease.
Tissue accumulation of polymorphonuclear neutrophils (PMN) in Inflammatory Bowel disease (IBD) might be, in part, due to a delay in apoptotic processes associated with the effects of their specific growth factors and inflammatory cytokines. We addressed this hypothesis by examining the activity of granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage CSF (GM-CSF) in the organ culture supernatants of colonic mucosal specimens and their regulatory effects on PMN apoptosis in patients with IBD. The contents of G-CSF and GM-CSF in the supernatants were measured by the enzyme-linked immunosorbent assays and PMN apoptosis was evaluated by acridine orange/ethidium bromide staining, respectively. Mucosal specimens obtained from patients with active IBD exhibited higher levels of G-CSF and GM-CSF activity than controls. Notably, the levels of G-CSF activity were approximately 1000-fold higher than those of GM-CSF activity. Freshly isolated PMN showed a time-related increase in the proportion of cells with characteristic features of apoptosis when they were incubated with the culture medium alone and exposure of PMN to recombinant G-CSF and GM-CSF caused a concentration-dependent inhibition of apoptosis. Incubation of PMN with the supernatants from patients with active IBD induced an inhibitory effect on PMN apoptosis; this effect was abrogated to a significant degree by pre-incubation of the supernatants with anti-G-CSF serum. This study suggests that PMN apoptosis may be delayed under the influence of soluble mediators, especially G-CSF, in the microenvironment of IBD-affected mucosa, thus providing possible mechanisms for tissue accumulation of PMN in IBD.
Acridine Orange↗
The extracellular calcium-sensing receptor is expressed in rat microglia and modulates an outward K+ channel.
The calcium-sensing receptor (CaR) is a G protein-coupled receptor that "senses" extracellular calcium ions (Ca2+o) as an extracellular first messenger. In this report, we have shown that the CaR is expressed in primary cultures of microglial cells derived from rat brain as assessed by RT-PCR using four CaR-specific primer pairs followed by sequencing of the amplified products, by northern blot analysis using a CaR-specific probe, as well as by immunocytochemistry and western analysis utilizing a specific polyclonal anti-CaR antiserum. In addition, raising Ca2+o from 0.75 to 3.0 mM or addition of the polycationic CaR agonist neomycin or a "calcimimetic" CaR activator (R-467; NPS Pharmaceuticals) increased the open state probability (Po) of a Ca(+)-activated K+ channel having a unitary conductance of 84+/-4 pS, indicating that the channel is modulated by the CaR. Therefore, our data strongly suggest that a functional CaR is expressed in cultured rat microglia, similar to that in parathyroid gland and kidney, which could potentially play an important role(s) in regulating microglial function.
Animals↗
A common mutation of cholesteryl ester transfer protein gene in dialysis patients.
BACKGROUND: In patients on maintenance hemodialysis, a decreased concentration of high-density lipoprotein cholesterol (HDL-C) is an apparent independent risk factor for vascular disease (VD). A common missense mutation of cholesteryl ester transfer protein (CETP) gene, D442G (Asp442 to Gly), increases HDL-C levels, but the mutation may also diminish the activity of reverse cholesterol transport. METHODS: We compared the genotype distribution of the D442G polymorphism and postprandial serum lipid levels between patients with and without VD in 414 hemodialysis patients. RESULTS: Serum levels of total cholesterol and HDL-C did not differ in patients with the mutation [group M (+)] and without the mutation [group M (-)] and in patients with and without VD. However, patients with below median HDL-C levels (< 45 mg/dl) had a significantly higher prevalence of VD than those with above median HDL levels (26.0 vs. 15.2%, P < 0.01). Moreover, in this low-HDL-C subgroup, group M (+) patients had a significantly higher prevalence of VD than group M (-) patients (54.5 vs. 24.4%, P < 0.05). In the subgroup, group M (+) patients with VD had higher levels of total cholesterol and a higher atherogenic index than those without VD, whereas group M (-) patients with VD had lower levels of total cholesterol and a lower atherogenic index than those without VD. CONCLUSIONS: The D442G mutation may be a risk factor for atherosclerotic complications in dialysis patients with HDL-C levels below 45 mg/dl. Atherogenic lipid profiles may promote atherosclerosis in the patients with the mutation, but not in those with no mutation.
Adult↗
Mammosomatotrophs develop within mammotroph clusters in bovine adenohypophysis.
The existence and distribution of mammosomatotrophs (MS cells) containing growth hormone (GH) and prolactin (PRL) in bovine adenohypophysis were detailed by a combined method of mirror sections and immunohistochemical staining. MS cells always occurred in bovine adenohypophysis but their number was low. In the midsagittal plane, the cells were observed in the hind dorsal, hind ventral and fore ventral region abundant in GH and PRL cells. Whereas, in the zona tuberalis where GH and PRL cells were less frequent, MS cells were not detected. MS cells were invariably solitarily distributed within mammotroph (PRL cell) clusters but not within somatotroph (GH cell) clusters. The proportion of MS cells declined as the ages proceeded and the appearance was spatially related to the arrangement of PRL cells. These findings indicated that, in bovine adenohypophysis, MS cells were differentially distributed and occurred in PRL cell clusters. The results strongly suggest that MS cells originate in GH cells pre-existed within PRL cell clusters with special reference to the functional activation of PRL cells.
Age Factors↗