Development of High Specific Speed Mixed Flow Compressors

Special PaperPg. 139-148The results of a study on the aerodynamic performance of a high specific speed, mixed flow compressor are presented. The specific speed was N. = 450 to 550 (m³/min) ½ (rpm) (m⁻¾ ), with approximately a 2.0 pressure ratio per stage. The flow path from the outlet of the mixed flow impeller was inclined in the axial direction and entered into a curved diffuser. A theoretical flow analysis and a performance test were performed. The slip factor for this type of compressor should be predicted by a different formula from that used for centrifugal compressors. Distributions of the flow velocity, temperature and pressure were measured, using a highly sensitive pressure transducer and a total temperature probe. The flow field, including the end wall boundary layer, was surveyed. The losses and the flow condition of the unsteady flow were analyzed. The compressor of N (Subscript s) = 450 to 500 showed high efficiency and handled a flowrate of about twice as much as a conventional centrifugal compressor. This development contributes tremendously in reducing the compressor size

ヒトウニョウビョウセイ ジンフゼン デ イジ トウセキチュウ ニ キュウセイ ハッショウ 1ガタ トウニョウビョウ オ ハッショウ シタ コウキ コウレイシャ ノ 1レイ

We herein presented a case of a ７５-year-old man who was referred to our hospital for hyperglycemia in a drowsy state following a convulsive seizure after receiving hemodialysis at another clinic. He had been receiving maintenance hemodialysis for non-diabetic renal failure from the age of ７３ years. He was diagnosed with diabetic ketosis because his blood glucose level was ７０７mg/dl, HbA１c ８．３％, glycoalbumin ４０．５％, serum osmolality ３２３mosm/kg, and ３-hydroxybutyric acid ５．８ mmol/l. Continuous intravenous insulin infusion therapy was immediately initiated and was changed to intensive insulin therapy on the ７th day after his admission. He did not have metabolic acidosis or serious dehydration associated with the acute metabolic derangement observed on arrival because fluid corrections for acid-base and electrolyte imbalances in the blood had been achieved by hemodialysis prior to his referral to our hospital. ΔCPR at six minutes in the glucagon loading test was hardly affected, indicating that his endogenous insulin secretory capacity was markedly reduced. The GAD antibody was negative. He had the haplotype of HLA DR４, which is considered to reflect disease susceptibility for type１diabetes in Japanese individuals. Acuteonset type １ diabetes mellitus was diagnosed based on the diagnostic criteria for acute-onset type１ diabetes mellitus （２０１２） by the Committee of the Japan Diabetes Society. At the time of his discharge, ８ units of insulin lispro were being administered prior to each meal in addition to ２ units of insulin glargine before sleeping. He was transferred to a local clinic on the ２３rd day after his admission. Although glycoalbumin had been measured every six months in the present case, it was not useful for detecting new onset diabetes. Therefore, blood glucose measurements before dialysis need to be regularly performed, even in dialysis patients with non-diabetic renal failure, in order to detect the new onset of diabetes at an early stage

Apc-Mutant Kyoto Apc Delta (KAD) Rats Are Susceptible to 4-NQO-Induced Tongue Carcinogenesis

Despite widening interest in the possible association between infection/ inflammation and cancer development, knowledge of this issue in relation to oral cancer remains inadequate. This study aimed to determine the susceptibility of Apc-mutant Kyoto Apc Delta (KAD) rats, which are vulnerable to developing inflammation-associated colorectal carcinogenesis, to 4-nitroquinoline 1-oxide (4-NQO)-induced tongue carcinogenesis in order to clarify the role of inflammation in oral cancer. KAD (20 males and 22 females) and F344/NS1c (22 males and 23 females) rats received drinking water with or without 4-NQO (20 ppm) for eight weeks. Histopathological and immunohistochemical analyses of the tongue were performed at week 20. Additionally, the mRNA expression of inflammatory cytokines in the tongue mucosa was determined at week 8. Tongue squamous cell carcinoma (SCC) developed in the KAD and F344/NS1c rats that received 4-NQO. Regardless of gender, the incidence and multiplicity of tongue SCC were greater in the KAD rats than in the F344/NS1c rats. In addition, the multiplicity of tongue SCC in the female KAD rats was significantly greater than that observed in the male KAD (p < 0.01) and female F344/NS1c rats (p < 0.05). The levels of inflammation and the mRNA expression of inflammatory cytokines in the tongue in the 4-NQO-treated female KAD rats were the highest among the rats given 4-NQO. These results show that KAD rats, particularly females, are susceptible to 4-NQO-induced tongue carcinogenesis, suggesting the utility of models employing KAD rats for investigating the pathobiology of oral (tongue) carcinogenesis associated with inflammation

Enhanced Development of Azoxymethane-Induced Colonic Preneoplastic Lesions in Hypertensive Rats

Metabolic syndrome is associated with an increased risk of colorectal cancer. This study investigated the impact of hypertension, a component of metabolic syndrome, on azoxymethane (AOM)-induced colorectal carcinogenesis using SHRSP/Izm (SHRSP) non-diabetic/hypertensive rats and SHRSP.Z-Leprfa/IzmDmcr (SHRSP-ZF) diabetic/hypertensive rats. Male 6-week-old SHRSP, SHRSP-ZF, and control non-diabetic/normotensive Wister Kyoto/Izm (WKY) rats were given 2 weekly intraperitoneal injections of AOM (20 mg/kg body weight). Two weeks after the last injection of AOM, the SHRSP and SHRSP-ZF rats became hypertensive compared to the control WKY rats. Serum levels of angiotensin-II, the active product of the renin-angiotensin system, were elevated in both SHRSP and SHRSP-ZF rats, but only the SHRSP-ZF rats developed insulin resistance, dyslipidemia, and hyperleptinemia and exhibited an increase in adipose tissue. The development of AOM-induced colonic preneoplastic lesions and aberrant crypts foci, was significantly accelerated in both SHRSP and SHRSP-ZF hypertensive rats, compared to WKY normotensive rats. Furthermore, induction of oxidative stress and exacerbation of inflammation were observed in the colonic mucosa and systemically in SHRSP and SHRSP-ZF rats. Our findings suggest that hypertension plays a role in the early stage of colorectal carcinogenesis by inducing oxidative stress and chronic inflammation, which might be associated with activation of the renin-angiotensin system

National trends in the outcomes of subarachnoid haemorrhage and the prognostic influence of stroke centre capability in Japan: retrospective cohort study

Objectives To examine the national, 6-year trends in in-hospital clinical outcomes of patients with subarachnoid haemorrhage (SAH) who underwent clipping or coiling and the prognostic influence of temporal trends in the Comprehensive Stroke Center (CSC) capabilities on patient outcomes in Japan.Design Retrospective study.Setting Six hundred and thirty-one primary care institutions in Japan.Participants Forty-five thousand and eleven patients with SAH who were urgently hospitalised, identified using the J-ASPECT Diagnosis Procedure Combination database.Primary and secondary outcome measures Annual number of patients with SAH who remained untreated, or who received clipping or coiling, in-hospital mortality and poor functional outcomes (modified Rankin Scale: 3–6) at discharge. Each CSC was assessed using a validated scoring system (CSC score: 1–25 points).Results In the overall cohort, in-hospital mortality decreased (year for trend, OR (95% CI): 0.97 (0.96 to 0.99)), while the proportion of poor functional outcomes remained unchanged (1.00 (0.98 to 1.02)). The proportion of patients who underwent clipping gradually decreased from 46.6% to 38.5%, while that of those who received coiling and those left untreated gradually increased from 16.9% to 22.6% and 35.4% to 38%, respectively. In-hospital mortality of coiled (0.94 (0.89 to 0.98)) and untreated (0.93 (0.90 to 0.96)) patients decreased, whereas that of clipped patients remained stable. CSC score improvement was associated with increased use of coiling (per 1-point increase, 1.14 (1.08 to 1.20)) but not with short-term patient outcomes regardless of treatment modality.Conclusions The 6-year trends indicated lower in-hospital mortality for patients with SAH (attributable to better outcomes), increased use of coiling and multidisciplinary care for untreated patients. Further increasing CSC capabilities may improve overall outcomes, mainly by increasing the use of coiling. Additional studies are necessary to determine the effect of confounders such as aneurysm complexity on outcomes of clipped patients in the modern endovascular era