A Successfully Treated Case of Posterior Ischemic Optic Neuropathy That Developed during Antihypertensive Therapy for Hypertensive Emergency

A 33-year-old woman developed hypertensive emergency (268/168 mmHg) with renal failure and hypertensive retinopathy. Four hours after the initiation of antihypertensive therapy with the continuous infusion of nicardipine, her blood pressure (BP) decreased to 168/84 mmHg; however, the patient developed blindness. She was diagnosed with posterior ischemic optic neuropathy (PION). Her BP was maintained at approximately 175/90 mmHg until her vision improved. Olmesartan was initiated on day 13, and her BP decreased to approximately 135/95 mmHg without the re-exacerbation of vision loss. Although the prognosis of PION is poor, its early diagnosis and gradual antihypertensive therapy may help preserve the patient's vision.

A case of malignant hypertension as a presentation of atypical hemolytic uremic syndrome

INTRODUCTION

Malignant hypertension (mHTN) damages multiple target organs, including the kidneys. mHTN has been regarded as one of the causes of secondary thrombotic microangiopathy (TMA); however, a high prevalence of complement gene abnormalities was recently reported in cohorts of mHTN.

CASE REPORT

We herein describe a 47-year-old male who presented with severe hypertension, renal failure (serum creatinine (sCr): 11.6 mg/dL), heart failure, retinal hemorrhage, hemolytic anemia, and thrombocytopenia. Renal biopsy findings were consistent with acute hypertensive nephrosclerosis. The patient was diagnosed with secondary TMA associated with mHTN. However, his previous medical history of TMA of unknown origin and family history of atypical hemolytic uremic syndrome (aHUS) suggested as aHUS presenting mHTN, and genetic testing revealed a pathogenic C3 mutation (p.I1157T). The patient required plasma exchange and hemodialysis for 2 weeks and was able to withdraw from dialysis by antihypertensive therapy without eculizumab. Renal function gradually improved to a sCr level of 2.7 mg/dL under antihypertensive therapy for 2 years after the event. There was no recurrence, and renal function was preserved throughout a 3-year follow-up.

DISCUSSION

mHTN is a common presentation of aHUS. In cases of mHTN, abnormalities in complement-related genes may be involved in the development of the disease.

Antibiotic prophylaxis for percutaneous renal biopsy: study protocol for a prospective randomized trial

Background

The major complication of renal biopsy is bleeding. Infection is an extremely rare complication of percutaneous renal biopsy, providing sterile techniques are used and bowel perforation does not occur. However, the questionnaire included in the Kidney Biopsy Guidebook 2020 in Japan reported that antibiotic prophylaxis was administered to patients undergoing percutaneous renal biopsy at 61% of 170 adult institutions and 57% of 54 pediatric institutions. The objective of this study is to show the non-inferiority of not administering antibiotic prophylaxis for percutaneous renal biopsy.

Methods

Patients aged ≥15 years who are scheduled to undergo percutaneous renal biopsy are eligible for inclusion in the study. Three hundred and sixty-four patients will be recruited at 6 hospitals. The patients will be randomly assigned at a 1:1 ratio to receive either a single dose of intravenous cefazolin (1 g) or no antibiotic prophylaxis. The primary outcome is the number of patients that exhibit positive urine cultures (>10⁵ colony-forming units/ml) 3 or 4 days after the renal biopsy, or at which point the patients are diagnosed with pyelonephritis until 3 or 4 days after the renal biopsy. The secondary outcomes are the number of patients who are diagnosed with pyelonephritis within 30 days after the renal biopsy, the number of patients who are diagnosed with puncture site infections within 30 days after the renal biopsy, the number of patients who are diagnosed with an infection other than pyelonephritis or a puncture site infection within 30 days after the renal biopsy, and the number of patients who experience cefazolin-induced side effects.

Discussion

This randomized controlled trial aims to show the non-inferiority of not administering antibiotic prophylaxis for percutaneous renal biopsy. If this study shows that antibiotic prophylaxis is not needed, it would help to ensure patient safety and prevent the development of antibiotic-resistant bacteria.

Trial registration

UMIN Clinical Trials Registry (UMIN-CTR) UMIN000042378. Registered on 7 Nov 2020.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06618-w.

Successful Sodium Level Correction with a 3% Saline Bolus before Intermittent Hemodialysis for a Patient with Severe Hyponatremia Accompanied by Acute Kidney Injury

A 60-year-old man presented to the emergency department with lightheadedness. He had severe hyponatremia (109 mEq/L) complicated by acute kidney injury (AKI) (serum creatinine: 9.08 mg/dL). Because he was somnolescent, his hyponatremia was initially treated by administering a 130-mL bolus of 3% saline 2 to 5 times per day for 5 days. He subsequently underwent intermittent hemodialysis without any neurological problems. Previous reports have described patients with hyponatremia and AKI being treated with continuous renal replacement therapy. However, our strategy might be a feasible, low-cost treatment strategy of treating patients with hyponatremia and AKI who do not require immediate hemodialysis.

Evaluation of the performance, operability, and safety of Plasauto μ, a new type of machine for cell-free and concentrated ascites reinfusion therapy, in a postmarketing clinical study

Cell‐free and concentrated ascites reinfusion therapy (CART) is performed by collecting the ascites from the patient, followed by filtration and concentration. Thereafter, concentrated cell‐free ascites is reinfused into the patient intravenously. The new type of machine, Plasauto μ, for managing the process of CART was launched onto the market. We have evaluated the machine through postmarketing clinical study in 17 patients with malignant ascites. The amounts of original and concentrated ascites were 3673 ± 1920 g and 439 ± 228 g, respectively. Recovery rates were acceptable regarding values of total protein, albumin, and IgG that were 55.6% ± 17.3%, 60.2% ± 20.8%, and 58.2% ± 20.5%, respectively. Recovery rates were positively associated with amounts of original ascites and negatively associated with total protein concentration. No adverse events related to the machine were observed. The new type of machine showed preferable performance in processing malignant ascites.

P0781ESTIMATION OF NEPHRON NUMBER IN CKD PATIENTS

Background and Aims

The nephron number is thought to be associated with clinical outcomes of chronic kidney disease (CKD). If the nephron number can be estimated in a clinical setting, it could become a strong tool to predict the outcomes. This preliminary study estimated nephron number in CKD patients, and examined the relationship between the nephron number and patient characteristics.

Method

Data from a multicenter study of the National Hospital Organization of Japan were analyzed, including 565 CKD patients aged over 14 years who underwent a kidney biopsy. The nephron number was estimated by the glomerular density in biopsy specimens and the renal cortex volume. The renal cortex volume was calculated by the previously established equation using ultrasound measurement of the kidney. Linear regression models were used to investigate the associations of the nephron number separately with age, sex, and estimated glomerular filtration rate (eGFR).

Results

A total of 50% of the patients were women, and the mean (±SD) age of the patients was 51±19 years. The mean eGFR was 63±32 ml/min/1.73m2, and the mean estimated number of non-sclerotic nephrons was 660,000±320,000 per kidney. A larger number of estimated nephron number was associated with younger age, male sex, and higher eGFR.

Conclusion

To the best of our knowledge, this was the first study to estimate the renal cortex volume and nephron number of CKD patients in the general clinical setting. The results from this study should provide powerful tools for nephrologists in routine clinical practice. Further investigations will be needed to verify the associations between the nephron number and clinical outcomes of CKD patients.

Treatment for renal anemia and outcomes in non-dialysis patients with chronic kidney disease: the current status of regional medicine according to the Kyoto Fushimi Renal Anemia (KFRA) study

BACKGROUND

The baseline data obtained in the CKD-JAC demonstrated that insufficient treatment was being provided for renal anemia by institutions specializing in renal disease. The objective of this study was to investigate the status of treatment for renal anemia, including renal/cardiovascular outcomes and mortality, at regional medical facilities since the development of long-acting erythropoiesis-stimulating agents (LA-ESA).

METHODS

Non-dialysis outpatients with chronic kidney disease and renal anemia were eligible. Anemia was treated based on the clinical condition of each patient and targeted hemoglobin (Hb) levels.

RESULTS

A total of 283 patients from 21 institutions were enrolled and followed up for a maximum of 3 years. A doubling of the serum creatinine level was observed in 89 patients, and renal replacement therapy was initiated in 57 patients. Multivariate Cox regression analysis revealed that a lower mean Hb level (mHb) and receiving fewer frequency of ESA during the follow-up period were independent determinants of the composite renal outcome and overall mortality. During the follow-up period, the percentages of patients with mHb of 10-10.9 g/dL and ≥ 11 g/dL were increased. Similar trends were seen regardless of whether the patients were treated by nephrologists or non-nephrologists. The frequency of ESA treatment was increased among the patients treated by non-nephrologists; however, it was much lower than nephrologists.

CONCLUSION

This study demonstrated that, in the era of LA-ESA treatment, higher Hb levels are associated with reduced composite renal outcomes at regional medical facilities. The importance of renal anemia management should be highlighted, even among non-nephrologists.

Chemotherapy in cancer patients undergoing haemodialysis: a nationwide study in Japan

Background

Cancer is a major cause of death in patients undergoing haemodialysis. However, information about the actual clinical practice of chemotherapy for patients with cancer undergoing haemodialysis is lacking. We conducted a nationwide survey using questionnaires on the clinical practice of chemotherapy for such patients.

Patients and methods

The nationwide survey included patients undergoing haemodialysis who were subsequently diagnosed with cancer in 20 hospitals in Japan from January 2010 to December 2012. We reviewed their clinical data, including cancer at the following primary sites: kidney, colorectum, stomach, lung, liver, bladder, pancreas and breast. The questionnaires consisted of the following subjects: (1) patient characteristics; (2) regimen, dosage and timing of chemotherapy; and (3) clinical outcome.

Results

Overall, 675 patients were registered and assessed for main primary cancer site involvement. Of 507 patients with primary site involvement, 74 patients (15%) received chemotherapy (44 as palliative chemotherapy and 30 as perioperative chemotherapy). The most commonly used cytotoxic drugs were fluoropyrimidine (15 patients), platinum (8 patients) and taxane (8 patients), and the dosage and timing of these drugs differed between institutions; however, the dosage of molecular targeted drugs (24 patients) and hormone therapy drugs (15 patients) was consistent. The median survival time of patients receiving palliative chemotherapy was 13.0 months (0.1-60.3 months). Three patients (6.8%) died from treatment-related causes and nine patients (20%) died of causes other than cancer. Of the 30 patients who received perioperative chemotherapy, 6 (20%) died of causes other than cancer within 3 years after the initiation of chemotherapy.

Conclusion

Among the haemodialysis patients with cancer who received chemotherapy, the rates of mortality from causes other than cancer might be high for both palliative and perioperative chemotherapy. Indications for the use of chemotherapy in patients undergoing haemodialysis should be considered carefully.

Post-infectious acute glomerulonephritis with vasculitis and pulmonary hemorrhage

An 84-year-old male complained of fever, cough, sputum, and appetite loss. His renal function rapidly worsened, and he had hypoalbuminemia and hypocomplementemia. His condition worsened and C-reactive protein levels were elevated. Vasculitis syndrome was suspected and he was administered 40 mg of prednisolone, although myeloperoxidase antineutrophil cytoplasmic antibody (ANCA), proteinase-3 ANCA and antiglomerular basement membrane antibody tests were negative. His body temperature decreased and fatigue promptly resumed. On renal biopsy, light microscopy revealed endocapillary and extracapillary glomerulonephritis. Vasculitis was detected in interlobular arteries. Immunofluorescence studies revealed granular deposits of C3 and IgG along capillary walls. Electron microscopy revealed dome-shaped small electron-dense granular subepithelial deposits. Acute post-infectious glomerulonephritis was suspected. Although his renal function improved, he developed hemoptysis and was diagnosed with pulmonary hemorrhage. He received methylprednisolone and plasma exchange, and his respiratory status improved gradually. This is an extremely rare case and suggests the importance of considering a differential diagnosis.

Gamma 1-heavy chain deposition disease accompanied by IgG kappa in serum, urine, and bone marrow

A 32-year-old Japanese woman presented with hypertension, nephrotic syndrome, microhematuria, and severe hypocomplementemia. Her serum creatinine concentration increased from 1.46 mg/dL (129.0 μmol/L) to 3.46 mg/dL (305.8 μmol/L) over 1 month. Renal biopsy revealed Congo red-negative nodular glomerulosclerosis accompanied by mesangial proliferation. There was extensive staining of immunoglobulin (Ig) G in the glomerular and tubular basement membranes and expanded mesangial regions. Staining was negative for IgA, IgM, and kappa and lambda light chains and positive for the gamma 1 IgG subclass. Staining for constant domains of the gamma heavy chains showed a deletion of the first constant domain (CH1). Electron microscopy revealed electron-dense deposits in the glomerular and tubular basement membranes and mesangium. These findings indicated gamma 1-heavy chain deposition disease (HCDD). Serum and urine immunoelectrophoresis revealed an IgG kappa monoclonal band, whereas bone marrow biopsy revealed monoclonal plasmacytosis with positive staining for kappa chains. HCDD associated with kappa light chain is extremely rare. We report the first case of HCDD with IgG kappa detected in the serum, urine, and bone marrow.

Glomerular endotheliosis in a pregnant woman with severe gestational proteinuria

Preeclampsia is the most common hypertensive disorder to occur during pregnancy. A healthy 38-year-old primipara presented with pretibial edema at 33 weeks of gestation followed by the development of proteinuria at 36 weeks of gestation. She had no past medical history of hypertension and was normotensive during gestation. Her proteinuria persisted after delivery, and she was also hypoalbuminemic. A renal biopsy revealed a remodeling of the glomerular basement membrane (GBM) with double contours. Some of the glomerular segments showed endothelial swelling. Immunoperoxidase staining for C4b-binding protein was positive and Protein S was weakly detected in the GBM. Electron microscopy revealed an expansion of the subendothelial zone as well as mesangial cell interposition. This case suggests that glomerular endotheliosis may therefore sometimes be present despite the absence of hypertension.

Predicting the outcome of chronic kidney disease by the estimated nephron number: the rationale and design of PRONEP, a prospective, multicenter, observational cohort study

BACKGROUND

The nephron number is thought to be associated with the outcome of chronic kidney disease (CKD). If the nephron number can be estimated in the clinical setting, it could become a strong tool to predict renal outcome. This study was designed to estimate the nephron number in CKD patients and to establish a method to predict the outcome by using the estimated nephron number.

METHODS/DESIGN

The hypothesis of this study is that the estimated nephron number can predict the outcome of a CKD patient. This will be a multicenter, prospective (minimum 3 and maximum 5 years follow-up) study. The subjects will comprise CKD patients aged over 14 years who have undergone a kidney biopsy. From January 2011 to March 2013, we will recruit 600 CKD patients from 10 hospitals belonging to the National Hospital Organization of Japan. The primary parameter for assessment is the composite of total mortality, renal death, cerebro-cardiovascular events, and a 50% reduction in the eGFR. The secondary parameter is the rate of eGFR decline per year. The nephron number will be estimated by the glomerular density in biopsy specimens and the renal cortex volume. This study includes one sub-cohort study to establish the equation to calculate the renal cortex volume. Enrollment will be performed at the time of the kidney biopsy, and the data will consist of a medical interview, ultrasound for measurement of the kidney size, blood or urine test, and the pathological findings of the kidney biopsy. Patients will continue to have medical consultations and receive examinations and/or treatment as usual. The data from the patients will be collected once a year after the kidney biopsy until March 2016. All data using this study are easily obtained in routine clinical practice.

DISCUSSION

This study includes the first trials to estimate the renal cortex volume and nephron number in the general clinical setting. Furthermore, this is the first prospective study to examine whether the nephron number predicts the outcome of CKD patients. The results from this study should provide powerful new tools for nephrologists in routine clinical practice.

TRIAL REGISTRATION

UMIN-Clinical Trial Registration, UMIN000004784.

Inheritance of an autosomal recessive disorder, Gitelman's syndrome, across two generations in one family

Gitelman's syndrome (GS) is an autosomal recessive disorder; it is rarely inherited over several generations. A 16-year-old boy showed hypokalemia and hypocalciuria. Clinically, he was diagnosed as GS because of diuretic responsiveness to furosemide but not thiazide. Genetic testing disclosed he was a compound heterozygote (T180K/V677M) for the SLC12A3 gene. Unexpectedly, the patient's father also showed hypokalemia and hypocalciuria. The genetic analysis showed he had an L849H mutation in addition to T180K. The present pedigree showed an extremely rare case. Diuretic tests are useful diagnostic methods, and genetic testing is necessary for precise evaluation of complicated cases as in this family.

[Myasthenia-like syndrome induced by cibenzoline overdose in a patient with chronic kidney disease]

A female in her late 60s with chronic kidney disease was admitted to the emergency department with complaints of dizziness four days prior to hospitalization. Cibenzoline (300 mg/day) was administered for atrial fibrillation, which was detected in an electrocardiogram. After three days, she experienced blepharoptosis and was admitted for suspected myasthenia gravis. However, the anti-acetylcholine receptor antibody and edrophonium tests were negative. On day four after hospitalization, she suffered from pneumonia with pleural effusion and she was put on a respirator for four days. From day 16 after hospitalization, she had diarrhea and her renal function worsened. At the same time, a gradual aggravation of right blepharoptosis, dull headache, weakness and difficulty in chewing were noted. She experienced dyspnea on day 31 after hospitalization. Chest X-ray film did not show a pneumonia shadow or pleural effusion, and arterial blood gases revealed hypercapnia; she was diagnosed as having CO2 narcosis due to respiratory muscle fatigue and was put on a respirator again. Myasthenia-like syndrome was suspected because of a probable overdose of cibenzoline and administration of cibenzoline was withdrawn. Her condition improved and she was taken off the respirator on day 35 after hospitalization. Repetitive stimulation of 5 Hz was applied to her right facial nerve along with evoked electromyogram(EMG) on days 2 and 11 after discontinuing cibenzoline. On day 2, the EMG showed a waning phenomenon, whereas no such phenomenon was seen on day 11. The blood concentration of cibenzoline immediately after withdrawal was extremely high (2448 ng/mL). When this drug is administered to a patient with chronic kidney disease, attention must be paid to the indication, dose, and manifestation of the possible side effects.

Transgenic overexpression of brain natriuretic peptide prevents the progression of diabetic nephropathy in mice

AIMS/HYPOTHESIS

Brain natriuretic peptide (BNP) is a potent vasorelaxing and natriuretic peptide that is secreted from the heart and has cardioprotective properties. We have previously generated hypotensive transgenic mice (BNP-Tg mice) that overproduce BNP in the liver, which is released into the circulation. Using this animal model, we successfully demonstrated the amelioration of renal injury after renal ablation and in proliferative glomerulonephritis. Glomerular hyperfiltration is an early haemodynamic derangement, representing one of the key mechanisms of the pathogenesis of diabetic nephropathy. Based on the suggested involvement of increased endogenous natriuretic peptides, the aim of this study was to investigate their role in the development and progression of diabetic nephropathy.

MATERIALS AND METHODS

We evaluated the progression of renal injury and fibrogenesis in BNP-Tg mice with diabetes induced by streptozotocin. We also investigated the effect of BNP on high glucose-induced signalling abnormalities in mesangial cells.

RESULTS

After induction of diabetes, control mice exhibited progressively increased urinary albumin excretion with impaired renal function, whereas these changes were significantly ameliorated in BNP-Tg mice. Notably, diabetic BNP-Tg mice revealed minimal mesangial fibrogenesis with virtually no glomerular hypertrophy. Glomerular upregulation of extracellular signal-regulated kinase, TGF-beta and extracellular matrix proteins was also significantly inhibited in diabetic BNP-Tg mice. In cultured mesangial cells, activation of the above cascade under high glucose was abrogated by the addition of BNP.

CONCLUSIONS/INTERPRETATION

Chronic excess of BNP prevents glomerular injury in the setting of diabetes, suggesting that renoprotective effects of natriuretic peptides may be therapeutically applicable in preventing the progression of diabetic nephropathy.

Contribution of visceral fat accumulation to the risk factors for atherosclerosis in non-obese Japanese

OBJECTIVE

To clarify the contributions of visceral fat tissue (VAT) mass deposition to the accumulation of risk factors for atherosclerosis in normal weight subjects.

SUBJECTS AND METHODS

We investigated the relationship between VAT accumulation and both risk factors and waist circumference in non-obese subjects. In the 955 normal weight Japanese subjects (782 men and 173 women), visceral fat area (VFA), subcutaneous fat area (SFA) and waist circumference were measured through computed tomography. Total cholesterol, high-density lipoprotein (HDL) cholesterol, triglyceride, uric acid, fasting blood glucose, and 2-hour postprandial glucose in the oral glucose tolerance test (OGTT) were measured to assess the risk factors for atherosclerosis.

RESULTS

In both men and women with normal body weight, VFA was correlated with total cholesterol (r=0.78 and r=0.71, respectively), HDL cholesterol (r=-0.89 and r=-0.82, respectively), triglyceride (r=0.72 and r=0.91, respectively), uric acid (r=0.71 and r=0.69, respectively), fasting blood glucose (r=0.84 and r=0.82, respectively), OGTT 2-hour postprandial glucose (r=0.75 and r=0.50, respectively), and systolic (r=0.93 and r=0.73, respectively) and diastolic (r=0.91 and r=0.73, respectively) blood pressure. The average number of risk factors was also correlated with VFA both in men (r=0.88, p=0.005) and women (r=0.91, p=0.003) with normal body weight. Based on the results of the multiple regression analyses, among VFA, SFA, body mass index (BMI) and age, VFA was considered to be the most important predictor for explaining the average number of risk factors. We also demonstrated that VFA was correlated with the waist circumference in normal weight men (r=0.74) and women (r=0.59). In normal weight subjects, the waist circumference equivalent to more than 1.0 of the average number of risk factors was 81 cm in men and 89 cm in women.

CONCLUSION

VAT accumulation itself plays a role as a risk factor for atherosclerosis irrespective of BMI, and measurement of VFA may be more important than that of BMI for predicting the presence of risk factors in normal weight subjects. Measurement of waist circumference also might be important for assessing the possibility of VAT accumulation leading to atherosclerosis.

Role of prostaglandin E receptor EP1 subtype in the development of renal injury in genetically hypertensive rats

One of the major causes of end-stage renal diseases is hypertensive renal disease, in which enhanced renal prostaglandin (PG) E2 production has been shown. PGE2, a major arachidonic acid metabolite produced in the kidney, acts on 4 receptor subtypes, EP1 through EP4, but the pathophysiological importance of the PGE2/EP subtypes in the development of hypertensive renal injury remains to be elucidated. In this study, we investigated whether an orally active EP1-selective antagonist (EP1A) prevents the progression of renal damage in stroke-prone spontaneously hypertensive rats (SHRSP), a model of human malignant hypertension. Ten-week-old SHRSP, with established hypertension but with minimal renal damage, were given EP1A or vehicle for 5 weeks. After the treatment period, vehicle-treated SHRSP showed prominent proliferative lesions in arterioles, characterized by decreased alpha-smooth muscle actin expression in multilayered vascular smooth muscle cells. Upregulation of transforming growth factor-beta expression and tubulointerstitial fibrosis were also observed in vehicle-treated SHRSP. All these changes were dramatically attenuated in EP1A-treated SHRSP. Moreover, EP1A treatment significantly inhibited both increase in urinary protein excretion and decrease in creatinine clearance but had little effect on systemic blood pressure. These findings indicate that the PGE2/EP1 signaling pathway plays a crucial role in the development of renal injury in SHRSP. This study opens a novel therapeutic potential of selective blockade of EP1 for the treatment of hypertensive renal disease.

Regulation of stanniocalcin 1 and 2 expression in the kidney by klotho gene

The klotho gene product and stanniocalcin (STC) 1 and 2 are recently identified molecules implicated in calcium and phosphorus homeostasis. In the present study, we investigated the regulation of STC1 and STC2 gene expression in the kidney by klotho gene expression. Mice deficient in klotho expression (klotho mice) have hypercalcemia and hyperphosphatemia, and increased renal gene expression of STC1 and STC2 compared with wild-type mice. Administration of vitamin D or CaCl(2) to wild-type mice causes upregulation of STC1 but STC2 gene expression is not altered significantly. On the other hand, treatment of klotho mice with low phosphorus diet results in partial decrease in STC2 gene expression with normalization of hyperphosphatemia. These findings indicate that klotho gene expression plays a crucial role in the regulation of renal stanniocalcin gene expression in vivo, at least partly, through the control of circulating calcium and phosphate concentrations.

Roles of connective tissue growth factor and prostanoids in early streptozotocin-induced diabetic rat kidney: the effect of aspirin treatment

BACKGROUND

Connective tissue growth factor (CTGF) is a cysteine-rich growth factor induced by transforming growth factor-beta (TGF-beta) and is thought to play a critical role in TGF-beta-stimulated extracellular matrix accumulation. To explore its involvement in early diabetic nephropathy, we investigated the time course of CTGF gene expression and its regulation in streptozotocin (STZ)-induced diabetic rat kidney.

METHODS

Northern blot analysis for CTGF, TGF-beta, and fibronectin expression was performed in the glomeruli of STZ-induced diabetic rats from 3 days to 12 weeks after the induction of diabetes, together with histological examination. To investigate the role of prostanoids in this process, aspirin was administered in one group of diabetic rats. Furthermore, CTGF expression was analyzed in rat mesangial cells cultured under high-glucose conditions.

RESULTS

Glomerular expression of CTGF and TGF-beta1 mRNA was coordinately upregulated as early as day 3, followed by fibronectin induction and mesangial matrix accumulation. Chronic aspirin treatment in diabetic rats significantly attenuated mesangial expansion, and effectively suppressed CTGF induction, as well as inhibiting the upregulation of TGF-beta1 and fibronectin expression. In cultured mesangial cells, aspirin treatment abolished high glucose-stimulated CTGF upregulation.

CONCLUSIONS

These results indicate that CTGF expressed in the glomeruli is upregulated in the early stage of STZ-induced diabetic nephropathy in rats, and could be a critical mediator of the development of diabetic glomerulosclerosis. In addition, the modulatory effects of aspirin during this process suggest a role of the cyclooxygenase pathway in the progression of diabetic nephropathy.

Angiogenic protein Cyr61 is expressed by podocytes in anti-Thy-1 glomerulonephritis

Dynamic recovery of glomerular structure occurs after severe glomerular damage in anti-Thy-1 glomerulonephritis (Thy-1 GN), but its mechanism remains to be investigated. To identify candidate genes possibly involved in glomerular reconstruction, screening was performed for genes that are specifically expressed by podocytes and are upregulated in glomeruli of Thy-1 GN. Among them, cysteine-rich protein 61 (Cyr61 or CCN1), a soluble angiogenic protein belonging to the CCN family, was identified. By Northern blot analysis, Cyr61 mRNA was markedly upregulated in glomeruli of Thy-1 GN from day 3 through day 7, when mesangial cell migration was most prominent. By in situ hybridization and immunohistochemistry, Cyr61 mRNA and protein were expressed by proximal straight tubules and afferent and efferent arterioles in normal rat kidneys and were intensely upregulated at podocytes in Thy-1 GN. Platelet-derived growth factor-BB (PDGF-BB) and transforming growth factor-beta1 (TGF-beta1), of which the gene expression in the glomeruli of Thy-1 GN was upregulated in similar time course as Cyr61, induced Cyr61 mRNA expression in cultured podocytes. Furthermore, supernatant of Cyr61-overexpressing cells inhibited PDGF-induced mesangial cell migration. In conclusion, it is shown that Cyr61 is strongly upregulated at podocytes in Thy-1 GN possibly by PDGF and TGF-beta. Cyr61 may be involved in glomerular remodeling as a factor secreted from podocytes to inhibit mesangial cell migration.

Plasma ghrelin and desacyl ghrelin concentrations in renal failure

Ghrelin is a novel hormone that possesses growth hormone (GH)-releasing, cardiovascular, and metabolic activities. Ghrelin is a unique acylated polypeptide, and the naked peptide, desacyl ghrelin, does not have the activity. This study examines plasma ghrelin concentrations in 41 patients with mild to severe renal diseases. Two kinds of radioimmunoassays were used: amino-terminal immunoreactivity represents ghrelin alone (N-IR), and carboxyl-terminal immunoreactivity corresponds to the sum of both ghrelin and desacyl ghrelin (C-IR). In all subjects, the plasma N-IR was much smaller than the C-IR, indicating that desacyl ghrelin predominates over ghrelin in the circulation. The plasma C-IR, but not N-IR, was significantly correlated with the serum creatinine level and was increased 2.8-fold in patients with end-stage renal disease compared with those in patients with normal renal function. The plasma GH concentration was significantly correlated with the plasma N-IR and the C-IR, as well as with the serum creatinine level. Bilateral nephrectomy in mice caused marked increase in the plasma C-IR without significant changes in the local C-IR and ghrelin mRNA level in the stomach, which is the main site of ghrelin production. These findings suggest that circulating ghrelin concentrations play a role in the regulation of blood GH concentrations and that the kidney is an important site for clearance and/or degradation of desacyl ghrelin. Furthermore, elevation of blood GH levels in renal failure seems to be caused by a mechanism other than alteration in the circulating ghrelin concentration.

Prevention of diabetic nephropathy in rats by prostaglandin E receptor EP1-selective antagonist

Local production of prostaglandins (PGs) in the kidney is increased in clinical and experimental diabetic nephropathy, but the role of PGs in the pathogenesis and progression of diabetic nephropathy has remained unclear. It is here shown that an orally active antagonist selective for the PGE receptor EP1 subtype potently prevents the progression of nephropathy in streptozotocin-induced diabetic rats. The effects are shown by ameliorated renal and glomerular hypertrophy, decreased mesangial expansion, inhibited transcriptional activation of transforming growth factor-beta (TGF-beta) and fibronectin, and complete suppression of proteinuria. In vitro, this agent completely inhibits TGF-beta and fibronectin upregulation in mesangial cells cultured under high-glucose conditions. These data indicate that the PGE2-EP1 system plays a crucial role in the development of diabetic renal injury in rats. It is further shown that both the EP1 antagonist and aspirin, a nonselective PG synthase inhibitor, markedly attenuate mesangial expansion, whereas only the EP1 antagonist inhibits glomerular hypertrophy and proteinuria, which suggests that these changes are caused by different mechanisms. This study reveals a potential usefulness of selective EP1 blockade as a novel therapeutic strategy for diabetic nephropathy and also brings a new insight into our understanding of this disease.

Role of connective tissue growth factor in fibronectin expression and tubulointerstitial fibrosis

Connective tissue growth factor (CTGF) is one of the candidate factors mediating downstream events of transforming growth factor-beta (TGF-beta), but its role in fibrogenic properties of TGF-beta and in tubulointerstitial fibrosis has not yet been clarified. Using unilateral ureteral obstruction (UUO) in rats, we analyzed gene expression of TGF-beta1, CTGF, and fibronectin. We further investigated the effect of blockade of endogenous CTGF on TGF-beta-induced fibronectin expression in cultured rat renal fibroblasts by antisense oligodeoxynucleotide (ODN) treatment. After UUO, CTGF mRNA expression in the obstructed kidney was significantly upregulated subsequent to TGF-beta1, followed by marked induction of fibronectin mRNA. By in situ hybridization, CTGF mRNA was detected mainly in the interstitial fibrotic areas and tubular epithelial cells as well as in parietal glomerular epithelial cells in the obstructed kidney. The interstitial cells expressing CTGF mRNA were also positive for alpha-smooth muscle actin. CTGF antisense ODN transfected into cultured renal fibroblasts significantly attenuated TGF-beta-stimulated upregulation of fibronectin mRNA and protein compared with control ODN transfection, together with inhibited synthesis of type I collagen. With the use of a reporter assay, rat fibronectin promoter activity was increased by 2.5-fold with stimulation by TGF-beta1, and this increase was abolished with antisense CTGF treatment. Thus CTGF plays a crucial role in fibronectin synthesis induced by TGF-beta, suggesting that CTGF blockade could be a possible therapeutic target against tubulointerstitial fibrosis.

Expression and role of angiotensin II type 2 receptor in the kidney and mesangial cells of spontaneously hypertensive rats

Angiotensin II type 2 (AT2) receptor is developmentally regulated and exerts antiproliferative and proapoptotic actions. Genetic ablation of this receptor in mice affects regulation of blood pressure, but the involvement of the AT2 receptor in the pathogenesis of hypertension remains unknown. In the present study, we examined developmental changes of angiotensin receptor subtypes in the kidney of stroke-prone spontaneously hypertensive rats (SHRSP), and compared them with those in normotensive Wistar-Kyoto rats (WKY). We also investigated the regulation and functional role of the AT2 receptor in cultured mesangial cells. Receptor binding and Northern blot analyses revealed that AT2 receptor expression is significantly lower in the SHRSP kidney than in the WKY kidney during the perinatal period, while AT1 receptor expression is not different between them. In WKY mesangial cells, AT2 receptor stimulation exerted a potent antiproliferative effect; this effect was not observed in SHRSP cells lacking the AT2 receptor expression. The expression of interferon regulatory factor (IRF)-1 paralleled the growth-dependent induction of AT2 receptor in WKY mesangial cells, and transfection of IRF-1 antisense oligonucleotide significantly suppressed AT2 receptor expression, indicating IRF-1-dependent regulation of AT2 receptor expression in mesangial cells. However, this induction was inefficient in SHRSP cells. Thus, we found impaired AT2 receptor expression in the SHRSP kidney in vivo and in mesangial cells in vitro. The unbalanced expression of renal angiotensin receptor subtypes with exaggerated AT1 receptor signaling during early life in SHRSP may play a role in the programming for hypertension and related renal injury.

Overexpression of brain natriuretic peptide in mice ameliorates immune-mediated renal injury

One of major causes of end-stage renal disease is glomerulonephritis, the treatment of which remains difficult clinically. It has already been shown that transgenic mice that overexpress brain natriuretic peptide (BNP), with a potent vasorelaxing and natriuretic property, have ameliorated glomerular injury after subtotal nephrectomy. However, the role of natriuretic peptides in immune-mediated renal injury still remains unknown. Therefore, the effects of chronic excess of BNP on anti-glomerular basement membrane nephritis induced in BNP-transgenic mice (BNP-Tg) were investigated and the mechanisms how natriuretic peptides act on mesangial cells in vitro were explored. After induction of nephritis, severe albuminuria (approximately 21-fold above baseline), tissue damage, including mesangial expansion and cell proliferation, and functional deterioration developed in nontransgenic littermates. In contrast, BNP-Tg exhibited much milder albuminuria (approximately fourfold above baseline), observed only at the initial phase, and with markedly ameliorated histologic and functional changes. Up-regulation of transforming growth factor-beta (TGF-beta) and monocyte chemoattractant protein-1 (MCP-1), as well as increased phosphorylation of extracellular signal-regulated kinase (ERK), were also significantly inhibited in the kidney of BNP-Tg. In cultured mesangial cells, natriuretic peptides counteracted the effects of angiotensin II with regard to ERK phosphorylation and fibrotic action. Because angiotensin II has been shown to play a pivotal role in the progression of nephritis through induction of TGF-beta and MCP-1 that may be ERK-dependent, the protective effects of BNP are likely to be exerted, at least partly, by antagonizing the renin-angiotensin system locally. The present study opens a possibility of a novel therapeutic potential of natriuretic peptides for treating immune-mediated renal injury.

Role of connective tissue growth factor in profibrotic action of transforming growth factor-beta: a potential target for preventing renal fibrosis

Tubulointerstitial fibrosis is a crucial process determining the progression and prognosis of various renal diseases. Connective tissue growth factor (CTGF), a novel fibrogenic protein induced by transforming growth factor-beta (TGF-beta), is upregulated in various clinical and experimental nephropathies, but the significance of CTGF in the profibrotic action of TGF-beta is still poorly defined. To explore the implication of CTGF in renal fibrosis, we investigated gene expression of CTGF, fibronectin, and alpha1(I) collagen in an obstructive nephropathy model in rats. Furthermore, to elucidate the role of CTGF in TGF-beta-stimulated extracellular matrix accumulation, we analyzed the effects of blockade of endogenous CTGF using antisense oligodeoxynucleotides (ODNs) in cultured rat renal fibroblasts. After unilateral ureteral obstruction, TGF-beta1 and CTGF messenger RNA (mRNA) expression in the obstructed kidney was coordinately upregulated from the early stage of interstitial fibrosis, followed by marked induction of fibronectin and alpha1(I) collagen mRNA expression. In cultured normal rat kidney fibroblast (NRK-49F) cells, CTGF antisense ODN transfection significantly attenuated TGF-beta1-induced fibronectin and alpha1(I) collagen mRNA expression compared with control reverse ODNs. These results indicate that CTGF has a crucial role in the profibrotic action of TGF-beta in renal fibroblasts, providing a potential therapeutic target against tubulointerstitial fibrosis.

The enantioselective immunoaffinity extraction of an optically active ibuprofen-modified peptide fragment

Acyl glucuronides are known to produce the covalently bound protein adducts which may be the cause of hypersensitivity and toxic responses to acidic drugs. The structural analysis of the drug-protein adducts is therefore needed. From this point of view, we developed an enantioselective immunoaffinity extraction method, which employs an immobilized antibody to specifically isolate peptide fragments that have been modified with optically active ibuprofen. Rabbits were immunized with (S)-ibuprofen coupled to bovine serum albumin through a beta-alanine group. The elicited antibody strongly recognizes the asymmetric center and the isobutylphenyl moiety of (S)-ibuprofen and its conjugates but has a low affinity for their anti podes. A 0.5-mL aliquot of the immunosorbent (11.5 mg of IgG/mL gel) prepared by immobilization of the antibody was capable of retaining up to 1 microg of (S)-ibuprofen. When a mixture of substance P with (R)- and (S)-ibuprofen-modified substance P was loaded on the immunosorbent, the (S)-ibuprofen-modified substance P was selectively retained. The modified peptide was quantitatively recovered by elution with 10 mM ammonium acetate buffer (pH 5.0)/methanol (5:95, v/v). The proposed method would be useful for the structural characterization of optically active ibuprofen-modified human serum albumin.

Altered growth response to prostaglandin E2 and its receptor signaling in mesangial cells from stroke-prone spontaneously hypertensive rats

OBJECTIVE

Prostaglandin (PG) E2, a major arachidonic acid metabolite in the kidney, acts on four receptor subtypes (EP1, EP2, EP3 and EP4). One of major causes of end-stage renal failure is hypertensive renal disease, in which enhanced renal PGE2 production has been shown. In this study, to explore the pathophysiological significance of EP subtypes in the kidney, we examined the role of EP subtypes on proliferation of mesangial cells (MCs) from stroke-prone spontaneously hypertensive rats (SHRSPs), which show faster growth than those from normotensive Wistar-Kyoto rats (WKYs).

DESIGN AND METHODS

Using MCs from SHRSPs and WKYs, we investigated DNA synthesis and its upstream event, the phosphorylation of extracellular signal-regulated kinase (ERK), together with the gene expression of EP subtypes.

RESULTS

Sulprostone, an EP1 agonist, dose-dependently increased DNA synthesis and the phosphorylation of ERK in MCs from both strains. The EP4 agonist, 11-deoxy-PGE1, inhibited sulprostone-induced phosphorylation of ERK in WKY-MCs. In contrast, 11-deoxy-PGE1 failed to inhibit the ERK activity in SHRSP-MCs. Interestingly, cAMP production mediated by EP4 was markedly attenuated in SHRSP-MCs as compared with that in WKY-MCs, despite the overproduction of endogenous PGE2 in SHRSP-MCs. Similar gene expressions of EP1 and EP4 and only faint expression of EP3 were detected in MCs from both strains.

CONCLUSIONS

These results indicate that the PGE2/EP4 system counteracts the PGE2/EP1 system at the level of the intracellular signaling pathway. The altered EP4 signaling may play a critical role in the exaggerated mesangial growth in SHRSPs.

Molecular cloning and expression of a novel klotho-related protein

Klotho protein is a novel beta-glucosidase-like protein produced predominantly in the kidney. The klotho mouse, which genetically lacks klotho gene expression, manifests various systemic phenotypes resembling aging. In the present study we succeeded in isolating a novel human protein structurally related to klotho protein. The protein possesses one beta-glucosidase-like domain and is 42% identical with klotho protein at the amino acid level. Unlike klotho protein, it possesses neither a signal sequence nor a transmembrane domain, suggesting that it is a cytosolic protein, and thus was termed cytosolic beta-glucosidase-like protein-1 (cBGL1). By Northern blot analysis cBGL1 mRNA was expressed most abundantly in the liver, followed by the small intestine, colon, spleen, and kidney. When klotho and cBGL1 gene expression was examined in renal cell carcinoma tissues, both klotho and cBGL1 mRNA levels in tumors were lower than those in nontumor regions, suggesting that renal epithelial cells may lose klotho and cBGL1 gene expression during the course of malignant transformation. In conclusion, we describe the primary structure and gene expression of a novel protein related to klotho protein.

Kidney produces a novel acylated peptide, ghrelin

Ghrelin is a novel growth hormone-releasing peptide with a unique acylated structure. Here we reveal that prepro-ghrelin gene is expressed in the mouse kidney and glomerulus. We also show by reverse-phase high performance liquid chromatography coupled with radioimmunoassay that the mouse kidney does produce ghrelin. The ghrelin immunoreactivity in the mouse kidney is 6.79+/-0.48 fmol/mg (n=5), which is much more abundant than that in the mouse plasma of 0.339+/-0.029 fmol/microl (n=6). Furthermore, prepro-ghrelin gene is expressed in cultured rat mesangial cells, fibroblast-like NRK-49F cells and mouse podocytes, but not in rat epithelial cell-like NRK-52E cells. Ghrelin receptor gene is also expressed in the rat kidney. These findings demonstrate that the kidney, glomerulus and renal cells express prepro-ghrelin gene and ghrelin is produced locally in the kidney, and suggest the endocrine and/or paracrine roles of ghrelin in the kidney.

Disruption of klotho gene causes an abnormal energy homeostasis in mice

klotho mice, which genetically lack klotho gene expression, are characterized with various systemic phenotypes resembling human aging, and also with growth retardation. Here we show that klotho mice have a barely detectable amount of the white adipose tissue but their brown adipose tissue (BAT) is comparably preserved. Glucose tolerance and insulin sensitivity in klotho mice are increased compared to those in wild-type mice as revealed by intraperitoneal glucose and insulin tolerance tests. Uncoupling protein-1 gene expression of BAT and body temperature in klotho mice are lower than those in wild-type mice, suggesting that klotho mice have less energy expenditure than wild-type mice. Histological examination suggests that klotho mice possess less energy storage than wild-type mice with respect to glycogen in the liver and lipid in BAT. All these changes of parameters for energy homeostasis in klotho mice are very similar to those reported under food-restricted conditions. However, the amount of food intake is not different between klotho and wild-type mice when normalized for body weight. The present study elucidates the importance of klotho gene expression for the maintenance of normal energy homeostasis.

[Development and evaluation of the health management system including medical images]

In the field of occupational health management, there are many areas in which a number of X-ray films that are associated with health checkup data for longitudinal health management of high risk groups exposed to dusts and specific carcinogenetic chemicals can be used. To make comprehensive use of the medical checkup data, we examined and evaluated basic techniques in which medical images such as radiographs can be linked to the medical checkup data in a form of computer data. A three-step procedure system was developed based on the IS&C system which is a common specification of medical images: 1) data convert and barcode printing system, 2) film digitizing and database management system, 3) utilizing system of health checkup data including a medical image system. Experiments were done using the system and it was found that processing efficiency seemed to be less and/or varied depending on process types. It was also found that the extraction of data from existing systems and the storage methods of data onto a magnetooptical disk are special issues to be resolved in our system.

Ameliorated glomerular injury in mice overexpressing brain natriuretic peptide with renal ablation

Brain natriuretic peptide (BNP) is a cardiac hormone produced by the ventricle, and its secretion is markedly increased in heart failure, hypertension, and renal failure. Transgenic mice that overexpress BNP in the liver (BNP-Tg) were recently generated, resulting in low BP. To elucidate the role of BNP in renal pathophysiology, the effect of chronic excess of BNP in transgenic mice on glomerular injury after subtotal nephrectomy induced by resection of the renal poles was examined. After nephrectomy, glomerular cross-sectional areas in control nontransgenic mice markedly increased as compared with those in sham-operated mice (+81 +/- 7%), whereas there was only a modest increase in BNP-Tg (+10 +/- 6%). Expansion of the mesangial area and increase in the intraglomerular cell number were also inhibited in BNP-Tg. Glomerular expressions of transforming growth factor-beta and fibronectin were increased with hypertrophy and were significantly suppressed in BNP-Tg. Furthermore, increases in the urinary albumin excretion and BP were significantly ameliorated in BNP-Tg. Chronic hydralazine treatment in nephrectomized nontransgenic mice failed to inhibit glomerular hypertrophy. These findings indicate that the chronic excess of BNP in mice ameliorates glomerular hypertrophy and mesangial expansion after renal ablation. The results also suggest that the observed effects of natriuretic peptides under reduced renal mass are not due merely to systemic BP reduction and may be therapeutically applicable in various renal diseases.

Rat receptor-activity-modifying proteins (RAMPs) for adrenomedullin/CGRP receptor: cloning and upregulation in obstructive nephropathy

Adrenomedullin (AM) is a potent vasorelaxing peptide originally isolated pheochromocytoma. Recently, a family of receptor-activity-modifying proteins (RAMPs 1-3) were identified in humans. Associated with the calcitonin receptor-like receptor (CRLR), RAMP2 or RAMP3 may function as the AM receptor. Here we cloned rat RAMP family, analyzed their distribution in rat tissues, and examined regulation of their expression in the kidney using an obstructive nephropathy model. Northern blot analyses revealed that the RAMP family genes are expressed in various tissues with different tissue specificity; RAMP1 is abundantly expressed in the brain, fat, thymus, and spleen, RAMP2 in the lung, spleen, fat, and aorta, while RAMP3 is most abundant in the kidney and lung. After ureteral obstruction, RAMP1, RAMP2, and CRLR gene expressions in the obstructed kidney were markedly upregulated, whereas RAMP3 expression was unchanged. Thus, RAMPs are regulated differently in obstructive nephropathy, suggesting their distinct roles in renal pathophysiology.

[An investigation on ethylene oxide sterilization management in medical institutions]

The present study describes an investigation on the use and management of ethylene oxide (EO) which is used mainly as a sterilant in medical institutions in a Cabinet-order designated city. Information was obtained from a self-administered questionnaire on safety and health matters related to sterilization with EO gas. The questionnaire was sent to 189 medical institutions including major hospitals and randomly selected clinics. 127 questionnaire were returned and the analysis was carried out for 120 respondents, excluding seven respondents whose answers were found to be inappropriate. The proportion of medical institutions, employing more than 50 workers, in which an occupational health physician and/or health supervisor was appointed was 70% and was lower than for other industries. 1.6% of the employees engaged in EO sterilization activities in the hospitals, whereas in clinics the percentage was as high as 20%. Several problems were found both in the management and work methods with EO: operations were not isolated in 46%; gas leaks and back-streaming of exhaust gas were found in 59% and 41%, respectively; and personal protective clothing was not used in 69%. Improvement was found only for three items among the institutions where an occupational health physician was appointed. These results suggest that good workplace controls and practices are essential for medical institutions using hazardous materials including EO for sterilization.

Identification of a novel R642C mutation in Na/Cl cotransporter with Gitelman's syndrome

Gitelman's syndrome, a variant of Bartter's syndrome, is an inherited disorder characterized by hypokalemic metabolic alkalosis, hypomagnesemia, and hypocalciuria, and these abnormalities have recently been linked to the thiazide-sensitive Na/Cl cotransporter (TSC) gene. We evaluated three unrelated patients affected with this syndrome whose diagnosis was made based on clinical and biochemical features. The data of clearance studies in these patients were compatible with Gitelman's syndrome. We then investigated possible mutations of the TSC gene. In one patient whose parents are consanguineous, we identified a novel missense mutation in the TSC gene, which causes alteration of arginine to cysteine at codon 642 (R642C mutation) located in the cytoplasmic tail of the product. This mutation results in the loss of an MspI site in exon 15 of the TSC gene. MspI digestion analysis of genomic DNA fragments from the family was consistent with the autosomal recessive inheritance of the disorder, and presence of this mutation correlated with the clinical manifestations. Such mutation was not detected in 47 normal healthy subjects. In the second patient, we found another missense mutation in one allele of the TSC gene, which results in alteration of arginine to glutamine at codon 955. In the third patient, no mutation causing amino acid substitution was found in the TSC gene. These results indicate that the R642C mutation in TSC is critically important for impairment of this cotransporter function and also suggest the necessity of further investigations in the genetic background of Gitelman's syndrome.

A unique talin homologue with a villin headpiece-like domain is required for multicellular morphogenesis in Dictyostelium

Molecules involved in the interaction between the extracellular matrix, cell membrane and cytoskeleton are of central importance in morphogenesis. Talin is a large cytoskeletal protein with a modular structure consisting of an amino-terminal membrane-interacting domain, with sequence similarities to members of the band 4.1 family, and a carboxy-terminal region containing F-actin-binding and vinculin-binding domains [1] [2]. It also interacts with the cytoplasmic tail of beta integrins which, on the external face of the membrane, bind to extracellular matrix proteins [3]. The possible roles of talin in multicellular morphogenesis in development remain largely unexplored. In Dictyostelium, a eukaryotic microorganism capable of multicellular morphogenesis, a talin homologue (TALA) has previously been identified and shown to play an important role in cell-to-substrate adhesion and maintenance of normal elastic properties of the cell [4] [5] [6]. Here, we describe a second talin homologue (TALB) that is required for multicellular morphogenesis in the development of Dictyostelium. Unlike any other talin characterised to date, it contains an additional carboxy-terminal domain homologous to the villin headpiece.

[Computer-aided occupational health education for post-graduates]

Nowadays, it's inevitable that occupational physicians enhance the activities in the field of occupational health through the use of the computer. Moreover, computer-aided self-education programs are one of the most useful tools for occupational physicians because they must learn a large volume of multidiscipline expertise for occupational health. Thus, we tried to apply a practical training program using the software of our own making in the post-graduate training course of fundamental occupational health. One is a self-education software for the study of electrocardiograms, and the other is a simple system to manage the serial data of a medical checkup and the reports of an inspection tour in the workplace. By this system one is also able to receive information such as a chest X-ray via the internet. Twenty-three students appraised our programs as for the contents (easily understandable, adequate volume); teacher's attitudes (enthusiastic approach to the training, enough time for questions, attention to the reaction of the class) and free comments. Because 4.3 points (at most 5.0) on an average was obtained, we are encouraged to make multimedia instructional materials on occupational health.

[Application of Internet technology in public health]

Recent advances in telecommunication technology have been enormous. Application of this technology in public health has the potential to markedly improve global health through better surveillance and information systems. With this assumption the GHNet was established in 1994 by representatives from academia, WHO, Pan American Health Organization, the World Bank, NASA, IBM, and AT & T. The GHNet consists of seven components: 1) promotion of networking with the Internet among people in public health; 2) disease tele-monitoring; 3) distance learning system with the internet; 4) connection of non-governmental health organizations; 5) training cyberdocs who are educated in both public health and telecommunications; 6) establishment of an electronic scientific research server; and 7) a home page on the World Wide Web (WWW). In order to effectively incorporate the Internet into the field, connectivity and knowing how to use it are of critical concern. More and more facilities are connected to the Internet in Japan. However, few courses teaching how to utilize the Internet are provided for people in this field. An Internet training course for people in public health was held as joint venture of the World Health Organization (WHO) and the Global Health Network (GHNet) on October 31, 1996, at the 55th Annual Meeting of Japanese Society of Public Health. Most of the participants for the course were from local public health departments and very few had previous experience with the Internet before the course. During this course participants learned how to use e-mail, how to find health resources on the WWW, how to construct a home page, and how the Internet could be utilized to improve public health, with their computers actually hooked to the Internet. From this experience, we found that this kind of course is feasible and beneficial and hope that this course would serve as a model for training people in public health.

Pathogenetic analysis of five cases with a platelet disorder characterized by the absence of thromboxane A2 (TXA2)-induced platelet aggregation in spite of normal TXA2 binding activity

Five patients with mild bleeding tendencies characterized by defective thromboxane A2 (TXA2)-induced platelet aggregation are reported. The platelets of all the patients had the ability to bind exogenous TXA2. Bleeding time was markedly prolonged in one patient. In three of the five patients, synthetic TXA2 mimetic (STA2)-induced platelet responses, including IP3 formation, Ca2+ mobilization, phosphatidic acid formation and GTPase activities were selectively defective, suggesting impaired coupling between the TXA2 receptor and phospholipase C activation. However, in the remaining two patients, these responses were all within normal limits. This suggests that the defective site of this type of platelet disorder is heterogenous and that signaling mechanisms other than the TXA2 receptor-phospholipase C pathway are also involved in TXA2-induced platelet aggregation.

[A case of selective IgM deficiency associated with systemic lupus erythematosus]

We report a case of selective IgM deficiency associated with systemic lupus erythematosus (SLE). A 34-year-old female suffering from SLE was admitted with proteinuria and general fatigue. Laboratory findings revealed a very low serum IgM level, almost lower than 12 mg/dl. Renal biopsy findings showed diffuse proliferative lupus nephritis (DPLN). In immunofluorescent microscopy, IgG was the most strongly stained followed by IgA, but IgM staining was only faint. As for the immunophenotype of the T cells, the OKT4/OKT8 ratio was normal. Response to both phytohemagglutinin (PHA) and concanavalin A (ConA) was normal. However, responses of B cells to both pokeweed mitogen (PWM) and Staphylococcus aureus Cowan strain I (SAC) were significantly reduced. Surface IgM-positive B cells were decreased. These results indicate that the patient had B cell dysfunction, involving impairment of B cell differentiation. In this report, we discuss selective IgM deficiency and SLE documented in the literature.

Spontaneous right uretero-cutaneous fistula complicated by spontaneous rupture of the urinary bladder

A case of spontaneous right uretero-cutaneous fistula complicated by spontaneous rupture of the urinary bladder is presented. This morbid state is extremely rare and has not been previously reported to the best of our knowledge.

Delayed rupture of the spleen caused by an intrasplenic pseudoaneurysm following blunt trauma: case report

The delayed rupture of the spleen in a 12-year-old boy is reported. He was admitted with an isolated blunt splenic injury. Successive echograms revealed an enlarging hypoechogenic region in the spleen. A magnetic resonance imaging (MRI) scan showed that this hypoechogenic region was a splenic pseudoaneurysm. On his 7th hospital day the pseudoaneurysm ruptured. An emergency laparotomy with splenorrhaphy was performed. His subsequent clinical course was uneventful and the pseudoaneurysm was replaced by a hematoma that eventually resolved.

Regulating factors of liver regeneration after hepatectomy

The factors regulating liver regeneration were studied by measuring changes in the liver volume and serum hepatocyte growth factor (HGF) levels after hepatectomy. Changes in the liver volumes were studied in 68 hepatectomized patients, including (A) hepatoma patients who had chronic hepatitis or liver cirrhosis (n = 44) and (B) metastatic liver cancer patients who had normal liver parenchyma (n = 24). The hepatic volume increased by 13.8% of the remnant hepatic volume in group A and by 49.1% in group B. The examined factors included the percentage of resected liver volume (%RLV) and the results of laboratory tests. Regression analysis showed that in group A, both %RLV (beta = 0.46) and the serum total bilirubin (T-Bil) level (beta = -0.33) correlated significantly with the extent of liver regeneration and that in group B, only %RLV (beta = 0.78) correlated significantly with the regeneration. Serum HGF levels after hepatectomy were studied in 21 hepatectomized patients, including 11 hepatoma patients and 10 patients with some types of metastatic liver cancer. Serum HGF levels increased significantly after surgery in all 21 patients. Regression analysis, however, showed that the change in HGF was related to liver cirrhosis (beta = 0.46) and to the maximal postoperative T-Bil level (beta = 0.51) but not to the extent of liver regeneration after hepatectomy. These results suggest that liver regeneration is regulated primarily by factors relating to the percentage of the resected liver parenchyma and that serum HGF levels do not directly relate to liver regeneration after surgery.

Defective signal transduction induced by thromboxane A2 in a patient with a mild bleeding disorder: impaired phospholipase C activation despite normal phospholipase A2 activation

A patient with a mild bleeding disorder whose platelets responded defectively to thromboxane A2 (TXA2) was identified, and the mechanism of this dysfunction was analyzed. The platelets were defective in shape change, aggregation, and release reaction in response to synthetic TXA2 mimetic (STA2). When the platelet TXA2 receptor was examined with both a 125I-labeled derivative of a TXA2 receptor antagonist ([125I]-PTAOH) and [3H]-labeled TXA2 agonist ([3H]U-46619), the equilibrium dissociation rate constants (kd) and the maximal concentrations of binding sites (Bmax) of the platelets to both ligands were within normal ranges, suggesting that the binding capacity of their TXA2 receptor was normal. STA2 could not induce IP3 formation and intracellular Ca2+ mobilization, whereas these responses to thrombin were within normal ranges. GTPase activity was also decreased when the patient's platelet membrane was challenged with STA2. On the other hand, lysophosphatidylinositol formation, which is a direct indicator of phospholipase A2 (PLA2) activation, was found to be normal when the [3H]-inositol-labeled platelets were challenged with STA2. Thromboxane B2 (TXB2) was also produced in response to STA2. These results suggested that the abnormality in these platelets was impaired coupling between TXA2 receptor and phospholipase C (PLC) activation. Furthermore, it is also suggested that the activation of PLA2 and PLC are separable events in thromboxane-induced platelet activation.

[Organ preservation with the combination of vasopressin and catecholamine in brain dead donors]

Brain dead donor can not be maintained the systemic circulation more than 48 hours despite rather large dosage of catecholamine. The combined administration of arginine vasopressin (ADH) and catecholamine (epinephrine or dopamine) succeeded in long-term circulatory maintenance after brain death. We examined the renal and hepatic function by the method of circulatory maintenance. Twenty brain dead patients were randomly separated into two groups. Ten patients were maintained the systemic blood pressure with ADH and epinephrine (Group E). And the other ten were maintained with ADH and dopamine (Group D). Circulation was maintained with a small dosage of catecholamine at least six days in all donors. Urine output was well controlled, and serum BUN and creatinine were normal for 14 days. Daily creatinine clearance was always normal in both groups. Serum GPT, cholinesterase and alkaliphosphatase were the same in both groups, but total bilirubin was lower in group D than in group E on the seventh day. The combination of ADH and catecholamine preserved the kidney and liver after brain death for more than a week. This method will be of great value in organ transplantation from brain dead organ donors.

[Functional and morphological changes of the liver after brain death maintained with the combined administration of vasopressin and catecholamine]

We investigated the functional and morphological changes of the liver after brain death for long period maintained with the combined administration of arginine vasopressin (ADH) and catecholamine. Twenty five brain-dead patients suffered from severe closed head injury were studied. The average age was 38.2 y.o. Systemic circulation was maintained normal for at least 6 days with ADH and catecholamine. ADH was infused constantly with an average dosage of 0.3 mU/kg/min. Simultaneous infusion of catecholamine was adjusted to maintain the mean arterial pressure above 80 mmHg. The morphological changes were not remarkable in the liver cells throughout the study. Levels of activated partial thromboplastin time (APTT) except in 5 patients remained within normal range for two weeks. According to this data, it can be considered that there is no marked lowering in the activity of protein synthesis of the liver. The progressive increase of serum alkaline phosphatase, LAP, gamma-GTP, and total bilirubin were observed as the characteristic changes of the liver after brain death. Serum levels of total bilirubin were markedly elevated especially in the patients who received massive transfusion. Histologically, cell infiltration into the Glisson's sheath became remarkable in all cases as day proceeded. These findings suggest the dysfunction of bile excretion might occur due to the denervation from the brain.