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Biomedical subjects

Y Sasaki

Publications and source records attributed to Y Sasaki.

At least 19 recordsLinked to original sources

Pulmonary clearance of aerosolized 99mTc-DTPA in sarcoidosis I patients.

AIM: Sarcoidosis frequently affects the lungs of patients. Pulmonary clearance scintigraphy with Technetium-99m-diethylenetriaminepentaacetic acid ((99m)Tc-DTPA) aerosol may assess pulmonary involvement of sarcoidosis patients. The study investigated early pulmonary involvement of sarcoidosis I patients by assessing the pulmonary clearance of inhaled (99m)Tc-DTPA aerosol and the character of pulmonary clearance though systemic steroid therapy. METHODS: The pulmonary clearance of (99m)Tc-DTPA aerosol was investigated in 24 patients with suspected stage I sarcoidosis and 20 non-smoking healthy controls over 18 months. The radiological finding was evaluated by chest computed radiography (CR) and high resolution computed tomography (HRCT) and the histological diagnosis was performed by transbronchial lung biopsy and/or Scalen node biopsy. The sarcoidosis I patients with ocular involvement underwent 1 year-systemic steroid therapy and were followed up over totally 18 months. RESULTS: The histological diagnosis was proved in 13 out of the 24 patients that had no lung filed involvement on CR and HRCT. Accelerated pulmonary clearance of (99m)Tc-DTPA was observed in 10 out of the 13 sarcoidosis I patients. Nine out of 13 sarcoidosis I patients underwent systemic steroid therapy due to ocular involvement and the accelerated pulmonary clearance responded to therapy and improved in all of the 9 over 18 months. CONCLUSIONS: Acceleration of (99m)Tc-DTPA pulmonary clearance may be observed in sarcoidosis I patients and the acceleration will respond to systemic steroid therapy. Pulmonary clearance scintigraphy with (99m)Tc-DTPA aerosol may be useful for assessing pulmonary involvement before radiological changes emerge and sarcoidosis I patients with accelerated pulmonary clearance may undergo systemic steroid treatment.

Administration, Inhalation↗

Characterization of char derived from various types of solid wastes from the standpoint of fuel recovery and pretreatment before landfilling.

Carbonization is a kind of pyrolysis process to produce char from organic materials under an inert atmosphere. In this work, chars derived from various solid wastes were characterized from the standpoint of fuel recovery and pretreatment of waste before landfilling. Sixteen kinds of municipal and industrial solid wastes such as residential combustible wastes, non-combustible wastes, bulky wastes, construction and demolition wastes, auto shredder residue, and sludges were carbonized at 500 degrees C for 1h under nitrogen atmosphere. In order to evaluate the quality of char as fuel, proximate analysis and heating value were examined. The composition of raw waste had a significant influence on the quality of produced char. The higher the ratio of woody biomass in waste, the higher heating value of char produced. Moreover, an equation to estimate heating value of char was developed by using the weight fraction of fixed carbon and volatile matter in char. De-ashing and chlorine removal were performed to improve the quality of char. The pulverization and sieving method seems to be effective for separation of incombustibles such as metal rather than ash. Most char met a 0.5 wt% chlorine criterion for utilization as fuel in a shaft blast furnace after it was subjected to repeated water-washing. Carbonization could remove a considerable amount of organic matter from raw waste. In addition, the leaching of heavy metals such as chrome, cadmium, and lead appears to be significantly suppressed by carbonization regardless of the type of raw waste. From these results, carbonization could be considered as a pretreatment method for waste before landfilling, as well as for fuel recovery.

Carbon↗

Correlation between tumor response to first-line chemotherapy and prognosis in advanced gastric cancer patients.

BACKGROUND: In advanced gastric cancer, the relationship between tumor response and prognosis is far from clear. METHODS: We performed a pooled analysis on published data from 4593 patients in 25 randomized trials of first-line chemotherapy for advanced gastric cancer. A weighed analysis was used to investigate the correlation between objective response rate (RR) and time to progression (TTP) and overall survival time (OS). RESULTS: A moderate correlation was found between RR and TTP and OS (r = 0.49 and r = 0.45, respectively) in all 25 trials. In treatment arms without new drugs including irinotecan, taxanes, or oxaliplatin, RR also was associated with TTP and OS (r = 0.56 and r = 0.47, respectively). However, no association between RR and OS was found, whereas there was a moderate correlation between RR and TTP (r = 0.41) in treatment arms using new drugs. CONCLUSIONS: Our results indicated that response to treatment was related to TTP and OS. The potential role of objective response as a surrogate in chemotherapy trials of advanced gastric cancer warrants further investigation, especially with regard to treatment with new drugs.

Humans↗

Surface-emitted terahertz-wave generation by ridged periodically poled lithium niobate and enhancement by mixing of two terahertz waves.

Surface-emitted terahertz- (THz-) wave generation by difference-frequency mixing with ridge-shaped periodically poled lithium niobate (PPLN) was demonstrated. The PPLN had a ridge height of 300 microm, a thickness of 20 microm, and an interaction length of 35 mm. The ridge behaves as a slab waveguide for optical pump beams. The PPLN gives rise to THz waves in opposite directions, perpendicular to the pump-beam direction. Reflecting the THz wave on one side and overlapping it with the THz wave on the other side increased the total THz-wave intensity approximately 2.7 times compared with that without reflection and mixing.

Journal Article↗

Gene expressions of canine angiopoietin-1 and -2 in normal tissues and spontaneous tumours.

The angiopoietin (Ang) family of proteins are central to the regulation of angiogenesis. The purposes of this study were to determine cDNA sequences of canine Ang-1 and Ang-2 and investigate their expressions in normal tissues and spontaneous tumours. The cDNA sequences of canine Ang-1 and Ang-2 were 1,494 and 1,488 bp, and the deduced amino acid sequences were 497 and 495 residues, respectively. The cDNA sequences of canine Ang-1 and Ang-2 showed high homology with those of the other mammalian species. Canine Ang-1 and Ang-2 mRNA were detectable in all 22 normal tissues and spontaneous tumours. Higher mRNA expression level of canine Ang-2 was demonstrated in mammary simple carcinomas, haemangiosarcoma and hepatocellular carcinoma in comparison with normal tissues.

Amino Acid Sequence↗

Exploration of genes showing intramuscular fat deposition-associated expression changes in musculus longissimus muscle.

Marbling, as defined by the amount of intramuscular fat, is an economically important trait in beef cattle. Intramuscular fat deposition is postulated to arise mainly from a series of adipogenic events in intramuscular adipocyte-lineage cells and in the physiological or anatomical milieux surrounding them. This study was designed to investigate gene-expression patterns associated with fat deposition in musculus longissimus muscle, including adipocyte-lineage cells and part of the milieux. Differential-display PCR (ddPCR) was used to examine expression differences between low-marbled and high-marbled steer groups at 8, 10, 12 and 14 months of age, encompassing the time that marbling starts to appear. Seventy-four of 2114 total bands on ddPCR gel-bands were significant (P < 0.05) for the group effect, the interaction effect between group and age, or both the group and the interaction effects. Sequence analysis of 72 of these bands revealed 77 genes, including 35 annotated genes and 42 novel sequences. Among the 35 annotated genes, 6 (BTG2, PDHB, SORBS1, TRDN, TTN and MGP) have been related to changes in intramuscular fat deposition, possibly by exerting effects on adipocyte-lineage cells or on the milieux surrounding them.

Adipose Tissue↗

Genome-wide linkage disequilibrium in two Japanese beef cattle breeds.

There is little knowledge about the degree of linkage disequilibrium (LD) in beef cattle. This study aims to perform a genome-wide search for LD in Japanese Black and Japanese Brown beef cattle and to compare the level of LD between these two breeds. Parameter D' (the LD coefficient) was used as a measure of LD, and LD was tested for significance of allelic associations between syntenic and between non-syntenic marker pairs. Effects of breed, chromosome, genetic map distance and their interactions with D' were tested based on least squares analyses. Both breeds showed high levels of LD, which ranged over several tens of cM and declined as the marker distance increased for syntenic marker pairs. A rapid decline of the D' value was observed between markers that were spaced 5 and 20 cM apart. LD was significant in most cases for marker pairs <40 cM apart but was not significant between non-syntenic loci. The pattern of LD found in these two breeds was similar to that previously published for dairy cattle. The D' value between breeds was not significantly different (P > 0.05), but the interaction between breed and chromosome was highly significant (P < 0.001). Genetic selection seems to have caused the heterogeneity of the D' values among chromosomes within breed. These results indicate that LD mapping is a useful tool for fine-mapping quantitative trait loci of economically important traits in Japanese beef cattle.

Alleles↗

Elimination of CD4+ CD25+ regulatory T cells breaks down reovirus type 2-triggered and CpG ODN-induced prolonged mild autoimmune insulitis in DBA/1 mice.

We have reported previously that subclinical prolonged mild T helper (Th) 1-dependent autoimmune insulitis with impaired glucose tolerance in wealing DBA/1J mice, which is induced by the combined effects of reovirus type 2 (Reo-2) and synthetic 20-base oligodeoxynucleotides with CpG motifs (CpG ODN) (control mice). Compared with the control mice, newborn mice treated with monoclonal antibody (MoAb) against mouse CD25(+) CD4(+) T cells together with Reo-2 and CpG ODN greatly reduced the absolute number of splenic CD25(+) T cells and resulted in the development of severe insulitis, leading to an overt early diabetes. Moreover, the treatment of the MoAb increased production of interferon-gamma (IFN-gamma) and decreased that of interleukin-4 (IL-4) and transforming growth factor-beta1 (TGF-beta1) and developed high titre of autoantibodies against pancreatic islet cells. These evidences suggest that CD4(+) CD25(+) T cell may, at least in part, maintain tolerance to Reo-2-triggered and CpG ODN-induced prolonged mild Th1-dependent autoimmune insulitis, leading to the overt disease. This system may give a novel model to elucidate the mechanisms of the development of overt diabetes from borderline subclinical diabetes in virus-triggered autoimmune type I diabetes in human.

Animals↗

Prognosis of patients who develop cervical lymph node recurrence following curative resection for thoracic esophageal cancer.

Patients with esophageal cancer often display relapse at cervical nodes after surgery, but their prognosis and a suitable therapy remains unknown. We retrospectively reviewed the records for 35 patients who underwent esophagectomy with lymphadenectomy who then displayed relapse at the cervical lymph nodes alone between 1985 and 2003 in order to observe the prognostic factors for such patients. Median survival time from the date of recurrence for all 35 patients was 12 months with 1-year, 2-year, 3-year and 5-year survival rate of 47.2%, 26.5%, 17.7% and 8.8%, respectively. With regard to the initial treatment against cervical node recurrence, 15 patients were treated by radiotherapy alone, eight by chemoradiotherapy, 11 by surgery and one by chemotherapy alone. Univariate analysis revealed that cervical node dissection at the prior esophagectomy (yes/no, P = 0.0178), time to recurrence (> 9 months or < 9 months, P = 0.0497) and the number of relapsed nodes (solitary/multiple, P = 0.0029) were significant prognostic factors. Among these factors, the number of relapsed nodes (solitary/multiple) was found to be the only significant prognostic factor with an odds ratio of 2.409 and 95% confidence interval of 1.033-5.619 by multivariate analysis. In conclusion, cervical node metastasis is generally considered to be distant organ metastasis. However, if it is a solitary node recurrence, substantial survival can be attained by appropriate loco-regional therapy.

Aged↗

Preoperative chemotherapy for clinically node-positive patients with squamous cell carcinoma of the esophagus.

Lymph node metastasis is one of the strongest prognostic factors for patients with esophageal cancer. Whether neoadjuvant chemotherapy is effective for metastatic nodes and improves the prognosis of clinically node-positive patients is unknown. Seventy-seven patients with clinically node-positive esophageal cancer, who were given preoperative chemotherapy (5-fluorouracil, cisplatin and adriamycin) followed by surgery, were retrospectively analysed. The histological effectiveness of the chemotherapy against the main tumor in the resected specimen was correlated with nodal status and prognosis. Of the 77 patients, the histological effects in the main tumors were grade 3 in one patient (1.3%), grade 2 in 10 (13.0%), grade 1b in seven (9.1%), grade 1a in 50 (64.9%) and grade 0 in nine (11.7%). Eleven patients (14.3%) were found to be pathologically node-negative. The pathological stages were significantly earlier in responders (grades 3-1b) than in non-responders (grades 1a-0) (P = 0.0001). The responders showed a significantly lesser degree of lymph node metastasis (P = 0.0005), fewer metastatic nodes (2.2 +/- 3.1 vs. 12.0 +/- 20.5, P = 0.0482) and better survival (P = 0.002) than the non-responders. The most common failure pattern for the non-responders was lymphatic recurrence, with an incidence of 47.5% (28/59), while that for the responders was 16.7%. Responders to neoadjuvant chemotherapy show fewer metastatic nodes and better prognosis than non-responders. Neoadjuvant chemotherapy may offer clinical benefit to responders.

Antineoplastic Agents↗

Use of tacrolimus, a potent antifibrotic agent, in bleomycin-induced lung fibrosis.

Idiopathic pulmonary fibrosis has a poor prognosis and few efficacious treatments. The immunosuppressant cyclosporin A has been shown to inhibit tumour growth factor (TGF)-beta-induced collagen deposition in vitro, and is widely used in Japan as a potent antifibrotic agent. Tacrolimus (FK506) is another attractive immunosuppressant, which may be useful in the treatment of pulmonary fibrosis. The aim of the present study was to elucidate the antifibrotic effect of FK506. The inhibitory effect of FK506 on collagen synthesis in cultured lung fibroblastic cells, TIG-3-20, and its antifibrotic effect on bleomycin (BLM)-induced pulmonary fibrosis in mice was investigated. FK506 inhibited TGF-beta-induced collagen synthesis, and suppressed the expression of TGF-beta type I receptor (TbetaR-I) in TIG-3-20 cells. Consistent with the in vitro findings, FK506 treatment starting on day 6 attenuated BLM-induced pulmonary fibrosis, in part, via reduced TbetaR-I expression. FK506 treatment in the acute BLM injury phase unexpectedly increased pro-inflammatory cytokine levels in bronchoalveolar lavage fluid and enhanced lung injury, resulting in poor survival. In conclusion, the present results suggest that FK506 has a potent antifibrotic effect and may be useful for the treatment of pulmonary fibrosis, although its use in the acute inflammatory phase may exacerbate lung injury.

Animals↗

Plasmid profiles of virulent Rhodococcus equi isolates from soil environment on horse-breeding farms in Hungary.

The plasmid profiles of virulent Rhodococcus equi strains isolated on three horse-breeding farms located in different parts of Hungary were investigated. From 49 soil samples collected on the three farms, 490 R. equi isolates (10 from each sample) were obtained and tested for the presence of 15- to 17-kDa antigens (VapA) by immunoblotting and PCR. Ninety-eight VapA-positive isolates were detected from 30 of the 49 culture-positive samples with a prevalence ranging from 13.1% to 23.2%. Of the 98 virulent isolates, 70 contained an 85-kb type I plasmid, 13 contained an 87-kb type I plasmid, and 15 contained an 85-kb type III plasmid which had been uniquely isolated from soil isolates in the United States. This study demonstrates that the virulent form of R. equi is very widespread in the soil environment of these stud farms in Hungary and the plasmid pattern is different from farm to farm.

Actinomycetales Infections↗

Comparison of genetic gains per year for carcass traits among breeding programs in the Japanese Brown and the Japanese Black cattle.

The breeding program for beef cattle in Japan has changed dramatically over 4 decades. Visual judging was done initially, but progeny testing in test stations began in 1968. In the 1980s, the genetic evaluation program using field records, so-called on-farm progeny testing, was first adopted in Oita, Hyogo, and Kumamoto prefectures. In this study, genetic trends for carcass traits in these 3 Wagyu populations were estimated, and genetic gains per year were compared among the 3 different beef cattle breeding programs. The field carcass records used were collected between 1988 and 2003. The traits analyzed were carcass weight, LM area, rib thickness, s.c. fat thickness, and beef marbling standard number. The average breeding values of reproducing dams born the same year were used to estimate the genetic trends for the carcass traits. For comparison of the 3 breeding programs, birth years of the dams were divided into 3 periods reflecting each program. Positive genetic trends for beef marbling standard number were clearly shown in all populations. The genetic gains per year for all carcass traits were significantly enhanced by adopting the on-farm progeny testing program. These results indicate that the on-farm progeny testing program with BLUP is a very powerful approach for genetic improvement of carcass traits in Japanese Wagyu beef cattle.

Animals↗

[Successful off-pump coronary artery bypass for a patient with aplastic anemia].

We report a 61-year-old man with aplastic anemia who underwent successful off-pump coronary artery bypass (OPCAB) after being admitted for angina pectoris. Coronary angiography showed severe stenosis of the left main coronary artery. Preoperative WBC was 2,200/microl, neutrophil 704/microl, Hb 8.1g/dl, and PLT 16,000/microl. We conducted OPCAB on double vessels using left internal thoracic and radial artery grafts. Thirty units of platelets were transfused intraoperatively with little perioperaive hemorrhage. Because of high grade fever, we injected 150 microg granulocyte colony-stimulating factor (G-CSF) every 3 days postoperatively to prevent major infection. The combination of appropriate perioperative management and OPCAB yielded an effective result for a patient with severe hematological disorders causing pancytopenia.

Anemia, Aplastic↗

[Aortic root replacement in Marfan syndrome with hemophilia A].

A 34-year-old man with Marfan syndrome was admitted to our hospital for surgical treatment of aortic regurgitation due to annuloaortic ectasia. He had no history of bleeding complications. Preoperative investigation revealed a slight prolongation of an activated partial thromboplastin time, which went unnoticed. He underwent aortic root replacement with a composite valve graft. During the operation, he had excessive bleeding due to coagulopathy after the termination of cardiopulmonary bypass, and needed a large amount of blood transfusion to obtain hemostasis. Before his discharge from our hospital, he was diagnosed as mild hemophilia A because of the decline in his factor VII level. To our knowledge, there has been no published case of cardiac operations in Marfan syndrome with hemophilia A.

Adult↗

[New proximal anastomotic system in coronary artery bypass grafting].

The Heartstring proximal anastomotic system is a device designed to facilitate the creation of a clampless hand-sewn proximal anastomosis. Thirty-four patients who underwent coronary artery revascularization had 40 proximal anastomoses using the Heartstring device. There were 26 men and 8 women, with the mean age of 70 +/- 8.9 years. Thirty-one patients underwent coronary artery bypass grafting through off-pump procedures and 3 patients on-pump beating procedures. In all patients, saphenous vein grafts were anastomosed to the aorta using the Heartstring device, the median number of distal anastomoses being 2.4 +/- 0.7. Either emergent or urgent surgery was required in 14 patients (41%). Diseased aorta was found in 11 patients (32%). One patient (2.9%) died postoperatively due to ischemic necrosis of the small intestine and the colon. There was no occurrence of postoperative stroke. Of 40 saphenous vein grafts anastomosed with the Heartstring system, 39 (97.5%) were patent. The occluded saphenous vein was not considered to be device related. Our clinical experience demonstrated that the Heartstring system allow us to create clampless and reproductive hand-sewn proximal anastomosis and to decrease the incidence of neurological complication.

Aged↗

Involvement of cyclooxygenase-1, prostaglandin E2 and EP1 receptors in acid-induced HCO3- secretion in stomach.

We investigated the cyclooxygenase (COX) isoforms as well as prostaglandin E receptor EP subtypes responsible for acid-induced gastric HCO(3)(-) secretion in rats and EP receptor-knockout (-/-) mice. Under urethane anesthesia, a chambered stomach (in the presence of omeprazole) was perfused with saline, and HCO(3)(-) secretion was measured at pH 7.0 using a pH-stat method and by adding 2 mM HCl. Mucosal acidification was achieved by exposing the stomach for 10 min to 50 or 100 mM HCl. Acidification of the mucosa increased the secretion of HCO(3)(-) in the stomach of both rats and WT mice, in an indomethacin-inhibitable manner. The acid-induced gastric HCO(3)(-) secretion was inhibited by prior administration of indomethacin and SC-560 but not rofecoxib in rats and mice. Acidification increased the PGE(2) content of the rat stomach, and this response was significantly attenuated by indomethacin and SC-560 but not rofecoxib. This response was also attenuated by ONO-8711 (EP1 antagonist) but not AE3-208 (EP4 antagonist) in rats and disappeared in EP1 (-/-) but not EP3 (-/-) mice. PGE(2) increased gastric HCO(3)(-) secretion in both rats and WT mice, and this action was inhibited by ONO-8711 and disappeared in EP1 (-/-) but not EP3 (-/-) mice. These results support a mediator role for endogenous PGs in the gastric response induced by mucosal acidification and clearly indicate that the enzyme responsible for production of PGs in this process is COX-1. They further show that the presence of EP1 receptors is essential for the increase in the secretion of HCO(3)(-) in response to mucosal acidification in the stomach.

Animals↗