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Shinichi Nishi

Publications and source records attributed to Shinichi Nishi.

At least 19 recordsLinked to original sources
PubMed2006

A case of Takayasu arteritis complicated with glomerulonephropathy mimicking membranoproliferative glomerulonephritis: a case report and review of the literature.

In this report, we describe the case of a 50-year-old Japanese woman with Takayasu arteritis who developed severe proteinuria and renal dysfunction. Abdominal computed tomography did not show narrowing of both renal arteries. Although her levels of C-reactive protein were negative, plasma vascular endothelial growth factor (VEGF) and serum interleukin (IL)-6 levels were elevated. Renal biopsy showed glomerulonephropathy mimicking membranoproliferative glomerulonephritis (MPGN) with glomerular capillary wall thickening (double contour). This was accompanied by mesangial cell proliferation and moderate increase of mesangial matrix without deposits of C3. These findings are quite different from MPGN as electron microscopy did not show subendothelial deposit and circumferential mesangial interposition. Here, we present the case of Takayasu arteritis associated with MPGN-like renal manifestation and elevated VEGF and IL-6. The presence of elevated VEGF and IL-6 could be factors that might contribute to MPGN-like appearance.

Biopsy↗
PubMed2006

Immunohistochemical evidence of activated lectin pathway in kidney allografts with peritubular capillary C4d deposition.

BACKGROUND: Complement 4d (C4d) deposition in the peritubular capillary (PTC) in the kidney allograft is a useful diagnostic marker for humoral rejection. C4d is produced not only by the classical pathway but also by the lectin pathway of the complement activation cascade. We have recently reported the in situ role of the later phase of the complement cascade in renal allografts with C4d deposition; however, the initial process prior to C4d deposition is yet to be resolved. METHODS: To clarify the early phases of the complement activation cascade, we evaluated the deposition of initial proteins of the above two pathways; IgG, IgM, mannose-binding lectin (MBL), H-ficolin, L-ficolin, MBL-associated serine protease (MASP)-1 and MASP-2 in kidney allografts with PTC C4d deposition. RESULTS: Sixty kidney allograft specimens were divided into two groups on the basis of the presence of C4d deposition in PTC. The C4d-positive group (n = 18) included nine ABO-identical and nine ABO-incompatible cases, and the C4d-negative group (n = 42) had 34 ABO-identical and eight ABO-compatible (but not identical) cases. In the C4d-positive group, 16 of 18 cases showed diffuse H-ficolin and IgM deposition in PTC. In contrast, H-ficolin and IgM were not detected in PTC in the C4d-negative group. Other initial proteins were not detected in all cases. CONCLUSIONS: Our study suggested for the first time that the lectin pathway activated by H-ficolin may be involved in C4d deposition on PTC in the kidney allograft.

Adult↗
PubMed2006

Para-capillary electron-dense deposits reduce glomerular filtration in patients with primary glomerular diseases.

BACKGROUND: Electron-dense deposits are often found around glomerular capillary lumens in patients with glomerulonephritis, forming a portion of the blood-urine barrier (BUB). METHODS: Four hundred and four patients with primary glomerular diseases or donors for living-related kidney transplantation who underwent both percutaneous renal biopsy and renal clearance tests were included in the study. Sodium thiosulfate and paraamino hippurate double-clearance studies were performed with catheterized urinary collection. The filtration fraction (FF) was determined as follows: FF = sodium thiosulfate clearance/paraamino hippurate clearance (CPAH: ). Histomorphometric analyses were performed in 53 patients with overt para-capillary electron-dense deposits (PCEDD) by electron microscopic observations. RESULTS: Patients with membranous nephropathy and membranoproliferative glomerulonephritis showed significantly lower levels of FF than the donors for living-rebated kidney transplantation (normal controls). FF levels were significantly lower in patients with PCEDD than in those without (P < 0.001), while the levels of mean blood pressure and CPAH: were comparable in the two groups. The PCEDD/BUB ratio demonstrated a significant negative correlation with FF (P < 0.0001; r(2) = 0.331). Patients with a ratio of 0.5 or more showed significantly lower FF levels than those with a ratio of 0.25 or less. CONCLUSIONS: PCEDD significantly affected FF levels in patients with primary glomerular diseases. FF may not be an accurate indicator of intraglomerular blood pressure in patients with overt PCEDD.

Adult↗
PubMed2006

Nephrotic syndrome and IgA nephropathy in polycystic kidney disease.

A 70-year-old man with polycystic kidney disease developed nephrotic syndrome, deteriorating to renal insufficiency. Histological examination revealed IgA nephropathy. With treatment of prednisolone, an angiotensin-converting enzyme inhibitor, and an angiotensin II receptor-blocker, his proteinuria markedly decreased and renal function was stabilized. This case supports the idea that renal biopsy is needed in patients with polycystic kidney disease with nephrotic-range proteinuria, for appropriate treatment and prevention of renal failure.

Aged↗
PubMed2006

Duration of dialysis is a significant predictor of prolonged postoperative mechanical ventilation in dialysis-dependent patients undergoing cardiac surgery.

Prolonged mechanical ventilation is reported to correlate with increased risk of mortality after cardiac surgery. We designed the present study to determine the preoperative and intraoperative risk factors that could predict postoperative prolonged mechanical ventilation in dialysis-dependent patients undergoing cardiac surgery with cardiopulmonary bypass. Forty-four dialysis-dependent patients were divided into two groups; patients of group E were tracheally extubated within 24 h after admission to the intensive care unit postoperatively (n = 19) and patients of group L (n = 25) required more than 24 h of mechanical ventilation. All patients received hemofiltration during cardiopulmonary bypass and continuous veno-venous hemodialysis postoperatively. A multiple logistic regression analysis showed that duration of dialysis (>10 yr) and duration of surgery (>8 h) were independent risk factors of prolonged mechanical ventilation (>24 h). On admission to the intensive care unit, Pao2/Fio2 of group L was significantly lower than that of group E (294 +/- 135 versus 415 +/- 99 mm Hg) and the circulatory status of group L was worse than that of group E. The median (interquartile range) duration of intensive care unit stay in group E was 3 (3.00) days, which was significantly shorter than that of group L (5 [2.75] days). It is possible that longer surgery increases the likelihood of cardiac dysfunction and poor oxygenation in patients with a long history of dialysis.

Aged↗
PubMed2006

Renovascular hypertension: a unique cause of unilateral focal segmental glomerulosclerosis.

A 48-year-old man presented with malignant hypertension and massive proteinuria. Renal angiography showed complete obstruction of the left renal artery and 99mTc-mercaptoacetylglycine (MAG3) renography showed a nonfunctioning left kidney. Percutaneous transluminal renal angioplasty of the left renal artery was unsuccessful; hence, the patient underwent left nephrectomy because of uncontrolled hypertension and proteinuria. Histological examination of a right kidney specimen revealed lesions of focal segmental glomerulosclerosis with benign nephrosclerosis. In contrast, histology of the left kidney showed typical ischemic kidney with hypertrophy of arteriolar smooth muscle cells. The patient responded favorably to the nephrectomy, as his blood pressure and urinary protein dramatically decreased with no antihypertensive medication. This case illustrates the heterogeneous effect of the renin-angiotensin system on either kidney in patients with renovascular hypertension due to unilateral renal artery stenosis.

Glomerulosclerosis, Focal Segmental↗
PubMed2006

[The use of questionnaires for rotating residents in evaluating training in anesthesiology].

BACKGROUND: We prepared questionnaires for the rotating residents during their assignment for anesthesiology in the novel Japanese residency programs for the year 2004. METHODS: Questionnaires consisting of 39 items with 235 model answers for these items were prepared. The residents underwent three interviews by these questionnaires over the three-month training period. The number of correct answers for these questionnaires was recorded and evaluated using a computer database software. RESULTS: There was no significant correlation between the results of these questionnaires and the subjective evaluation by supervisors conducted during clinical training. On stepwise regression analysis, the results of the questionnaires for "American Society of Anesthesiologists Physical Status", "contraindications for epidural anesthesia", "complications of general anesthesia" and "initial procedures for patients in the operating room" correlated with the subjective evaluation by supervisors. CONCLUSIONS: Stepwise regression analysis was shown to be helpful in improving the questionnaires regarding the training in anesthesiology.

Anesthesiology↗
PubMed2006

The application of the hemoglobin saturation sensor and indocyanine green (ICG) for blood flow measurement.

BACKGROUND: The aim in this study is to evaluate a new blood flow measurement applying a hemoglobin saturation sensor and indocyanine green (ICG) in circuit and animal models. METHODS: 1) In the basic study, the blood was mixed in a tube with ICG, and a near-infrared sensor was placed in this tube. The standard curve of the relationship between ICG concentration and optical density was obtained. 2) In the circuit model, the blood was circulated by the roller pump. ICG was injected in this circuit and its concentration was calculated from the change in optical density at 810 nm. Rate of flow was calculated based on the Fick's principle. The validity of this method was evaluated by Bland and Altman analysis. 3) In the animal model, a hemoglobin saturation sensor was inserted into three anesthetized dogs via the jugular vein, and iced ICG was injected for calculating cardiac output. Cardiac output was calculated by the same theory of the circuit model. The validity of this method was also evaluated by Bland and Altman analysis. RESULTS: 1) A standard curve was drawn from 11 different points (r2=0.99). 2) The calculated flow rate correlated well with the actual flow rate (r2=0.97). 3) The calculated cardiac output correlated well with results obtained with the thermodilution method. CONCLUSIONS: Application of a hemoglobin saturation sensor and ICG to blood flow measurement was reliable and useful in both circuit and animal models. This method may be clinically useful for measurement of blood flow.

Animals↗
PubMed2005

Cesarean section at 28 weeks' gestation with resection of pheochromocytoma: perioperative antihypertensive management.

Pregnancy complicated by pheochromocytoma is potentially fatal. Pregnancy and labor increase the risk of hypertensive crisis as it may occur with the sudden release of catecholamine accompanying uterine contractility and straining. However, antepartum diagnosis reduces both maternal and fetal mortality, allowing for safe cesarean section and resection of tumor. We describe the management of perioperative hypertension for combined cesarean section and pheochromocytoma resection.

Adrenal Gland Neoplasms↗
PubMed2005

The morphological compensatory change of peritubular capillary network in chronic allograft rejection.

To clarify the compensatory hemodynamic alterations in the interstitium of renal allograft biopsies with chronic rejection, we evaluated the morphological changes in the peritubular capillary (PTC) network. Seven renal biopsy specimens from recipients with chronic rejection presenting with elevation of serum creatinine of 1.9 +/- 0.5 mg/dL were examined. Renal biopsy specimens from their counterpart donors were used as normal controls. In each specimen, non-pathological interstitial areas without fibrosis, tubular atrophy or cell infiltration were compared with pathological areas (PA) showing fibrosis and/or tubular atrophy using a computer image analysis. Morphological measurements revealed that the mean cut surface area of the PTC in the non-pathological and pathological interstitial areas in the recipient biopsies were significantly larger than that of the normal controls (p < 0.001 and 0.001, respectively). In the recipient biopsies, both of the mean cut surface areas of the tubules and PTC in the non-pathological areas were significantly higher than those in the PA (p < 0.001). The mean glomerular diameter in the recipient biopsies was also significantly higher than that of the donors (p < 0.01). In this study, we provided pathological evidence for the compensatory interstitial and glomerular hemodynamic alterations in kidney graft with chronic rejection and the condition as single kidney.

Adult↗
PubMed2005

Role of megalin, a proximal tubular endocytic receptor, in the pathogenesis of diabetic and metabolic syndrome-related nephropathies: protein metabolic overload hypothesis.

Megalin is an endocytic receptor on the apical membranes of proximal tubule cells (PTC) in the kidney, and is involved in the reabsorption and metabolism of various proteins that have been filtered by glomeruli. Patients with diabetes, especially type 2 diabetes, or metabolic syndrome are likely to have elevated serum levels of advanced glycation end products, liver-type fatty acid binding protein, angiotensin II, insulin and leptin, and renal metabolism of these proteins is potentially overloaded. Some of these proteins are themselves nephrotoxic, while others are carriers of nephrotoxic molecules. Megalin is involved in the proximal tubular uptake of these proteins. We hypothesize that megalin-mediated metabolic overload in PTC leads to compensatory cellular hypertrophy and sustained Na+ reabsorption, causing systemic hypertension and glomerular hyperfiltration via tubuloglomerular feedback, and named this as 'protein metabolic overload hypothesis'. Impaired metabolism of bioactive proteins such as angiotensin II and insulin in PTC may enhance hypertrophy of PTC and/or Na+ reabsorption. Sleep apnoea syndrome, a frequent complication of diabetes and metabolic syndrome, may cause renal hypoxia and result in relative overload of protein metabolism in the kidneys. The development of strategies to identify patients with diabetes or metabolic syndrome who are at high risk for renal metabolic overload would allow intensive treatment of these patients in an effort to prevent the development of nephropathy. Further studies on the intracellular molecular signalling associated with megalin-mediated metabolic pathways may lead to the development of novel strategies for the treatment of nephropathies related to diabetes and metabolic syndrome.

Diabetic Neuropathies↗
PubMed2005

Osteopontin expression in acute renal allograft rejection.

BACKGROUND: Osteopontin (OPN) is a potent chemoattractant for mononuclear cells that is up-regulated in various inflammatory states of the kidney. The role of OPN and its expression in human renal allograft rejection are unknown. METHODS: We examined by immunohistochemistry and in situ hybridization, renal biopsies from patients with acute rejection (N= 22), protocol biopsies without rejection (N= 9), and perioperative donor biopsies (N= 35) for intrarenal expression of OPN, and its correlation with clinical, laboratory, and histopathologic parameters. In the rejection biopsies, interstitial monocyte/macrophage infiltration, tubulointerstitial cell proliferation/regeneration and apoptosis were investigated. RESULTS: In the majority of rejection biopsies, OPN expression by proximal tubular epithelium was widespread, and tended to be enhanced in the tubules surrounded by numerous inflammatory cells. Conversely, in patients that did not experience episodes of rejection and in donor biopsies, OPN expression by proximal tubules was nil or weak. OPN mRNA was colocalized with its translated protein in the renal tubular epithelium. OPN expression positively correlated with the degree of interstitial inflammation (P < 0.05), CD68+ monocyte infiltration (P < 0.01), Ki-67+ regenerating tubular and interstitial cells (P < 0.05 and P < 0.005, respectively), but not with terminal deoxynucleotidyl transferase (TdT)-mediated deoxyuridine triphosphate (dUTP) nick-end labeling (TUNEL)-positive apoptotic tubular cells. CONCLUSION: These data suggest that inducible expression of OPN in the tubular epithelium may have a pathogenic role in acute renal allograft rejection by mediating interstitial monocyte infiltration and possibly tubular regeneration.

Acute Disease↗
PubMed2005

[General anesthesia by propofol infusion for delivery by cesarean section compared with sevoflurane anesthesia using bispectral index (BIS) monitoring].

BACKGROUND: We compared the postoperative effects of propofol and sevoflurane used for anesthesia during elective cesarean section, using bispectral index (BIS) monitoring. METHODS: Fourteen parturients were randomized into two groups (Propofol group; P group, Sevoflurane group; S group). All patients received thiopental and suxamethonium for induction and had orotracheal intubation in rapid sequence. All patients received 1% sevoflurane until delivery. In the P group, sevoflurane was stopped after delivery and propofol infusion was started, to achieve target BIS values below 60; the infusion rate was 6. 17 +/- 0.98 mg x kg(-1) x h(-1). Patients in the S group received 1% sevoflurane. All patients were given fentanyl and vecuronium as required. RESULTS: There were no significant differences between the two groups in their times for beginning drinking, walking, eating or removal of urinary catheters after the operations. There were no significant differences in total blood loss or intraoperative dose of oxytocin, but postoperative and total doses of oxytocin were significantly higher in those in the P group. CONCLUSIONS: Comparing the effects of propofol and sevoflurane on the postoperative condition of parturients, no differences could be detected. We can choose to use propofol instead of sevoflurane for cesarean section.

Adult↗
PubMed2005

[Lumbar epidural morphine for postoperative analgesia in children undergoing Nuss procedure].

BACKGROUND: We examined the effects of lumbar epidural morphine for postoperative analgesia in children after the Nuss procedure for funnel chest. METHODS: An epidural catheter was inserted from the L 3-4 interspace preoperatively (epidural group). Epidural morphine 30 microg x kg(-1) was given at the beginning of the operation. Postoperatively, epidural morphine 3 microg x kg(-1) x hr(-1) was infused. The frequency of demand for postoperative analgesia was retrospectively compared with that of children who had not received epidural morphine (control group). RESULTS: On the 0th postoperative day, the epidural group required fewer analgesics than the control group (0.50+/-0.30 vs. 2.50+/-1.00 x day(-1)). However, after the 1st postoperative day, the demand for analgesia did not differ between the two groups. CONCLUSIONS: Epidural morphine 30 microg x kg(-1) given at the beginning of operation provided effective analgesia on the 0th postoperative day after the Nuss procedure. However, epidural infusion of morphine 3 microg x kg(-1) x hr(-1) was not effective after the 1st postoperative day. Further study is needed to determine the lumbar epidural infusion dose of morphine adequate for use after the Nuss procedure.

Analgesia, Epidural↗
PubMed2005

A new method for measuring total coronary blood flow using the lithium dilution method.

BACKGROUND: The aim in this study is to evaluate a new method of measuring total coronary blood flow (TCBF) in (1) an in vitro model and in (2) an animal model by the lithium dilution method. METHODS: (1) Ringer's solution was circulated in a closed circuit with the main flow as a systemic circulation, and the side flow as a coronary circulation by a roller pump. Two peaks originating from the main and side flow were recorded by the lithium dilution method. The flow was calculated using the Fick principle based on the ratio of the areas under the curve. The validity of this method was evaluated by Bland Altman analysis. (2) Four beagles were anesthetized and subjected to insertion of two pulmonary artery catheters. The position of the catheters was confirmed as being in the pulmonary artery and in the right atrium. Lithium chloride solution was injected into the pulmonary artery and the change in lithium concentration at the right atrium was recorded. TCBF was estimated by the method used in the in vitro study. RESULTS: (1) The calculated flow correlated well with the actual flow (r2 = 0.86). (2) The estimated TCBF at baseline, with low-dose nitroglycerin, and with high-dose nitroglycerin was 206 +/- 43.0 mL/min, 304 +/- 50.3 mL/min, and 348 +/- 50.1 mL/min, respectively (mean +/- SE). TCBF was significantly increased by nitroglycerin infusion. CONCLUSION: A new method of measuring TCBF using the lithium dilution method was reliable and useful both in vitro and in an animal model. This may be clinically useful method for measuring TCBF.

Animals↗
PubMed2004

Different type and localization of CD44 on surface membrane of regenerative renal tubular epithelial cells in vivo.

BACKGROUND: CD44 is a transmembrane glycoprotein comprising an extracellular domain, a transmembrane domain, and a cytoplasmic tail. Previous studies demonstrated that CD44 was generally restricted to lateral-basal plasma membrane (PM) of epithelial cells, whether it localized on apical PM in vivo has not been clarified. METHODS: In this study, we used a gentamicin-induced acute tubular necrosis (ATN) and spontaneous recovery model in rats and two distinct antibodies, an anti-rat distal extracellular domain (OX49) of standard CD44 (CD44-OX49) and an anti-rat CD44 cytoplasmic tail (CD44CPT), to survey the localization of CD44-OX49 and CD44CPT on the PM in renal tubular epithelial cells in different recovery stages after ATN with immunohistochemistry and immunoelectron-microscopic examinations. RESULTS: CD44-OX49 was localized not only on the lateral-basal PM in tubular epithelial cells, but also on the apical surface membrane in PCNA-positive newly regenerative tubular epithelial cells in early recovery stages after ATN. However, CD44CPT was only localized on the lateral-basal PM. The immunoelectron-microscopic results showed that CD44-OX49 localization was changed from the apical to lateral to basal surface membrane in renal tubular epithelial cells during the recovery process after ATN, finally disappearing from basal PM when normal polarized epithelial cells formed. CONCLUSIONS: These results suggest that there were two types of CD44 including CD44 without a cytoplasmic tail localizing on the apical surface membrane related to newly regenerative epithelial cells, and CD44 with a cytoplasmic tail localizing on the lateral-basal PM related to establishment of tubular epithelial cell polarity after ATN in vivo.

Animals↗
PubMed2004

A case of Takayasu arteritis complicated with glomerulonephropathy mimicking membranoproliferative glomerulonephritis.

We report on a 65-year-old Japanese woman with Takayasu arteritis who developed severe proteinuria, hypertension, and renal dysfunction. Renal angiography demonstrated moderate irregular narrowing of both renal arteries. Renal biopsy showed glomerulonephropathy mimicking membranoproliferative glomerulonephritis (MPGN) with glomerular capillary wall thickening ("double contour") accompanied by mesangial cell proliferation and moderate increase of mesangial matrix without deposits of C3. Electron microscopy showed no subendothelial deposit and no circumferential mesangial interposition (CMI), and these findings are different from MPGN. In this report we present a case of Takayasu arteritis associated with glomerulonephropathy mimicking MPGN.

Aged↗