Teiichiro Aoyagi

Cadmium nephrotoxicity and evacuation from the body in a rat modeled subchronic intoxication

Background: Cadmium (Cd) is an important industrial pollutant, although its mechanism of toxicity has not been completely clarified. We studied Cd‐induced subchronic nephrotoxicity and the cadmium evacuation system in rats and cultured human renal tubular cells.

Laparoscopic heminephrectomy of a horseshoe kidney using microwave coagulator

CASE REPORT A 17-year-old man was referred to our hospital for right flank pain. An excretory urogram revealed no right kidney and malrotation of the left renal collecting system. Abdominal ultrasonography demonstrated a large complex cystic mass in the right renal region which was confirmed on computerized tomography to be a horseshoe kidney with severe hydronephrosis (part A of figure). After discussion of the indication and modes of nephrectomy, the patient and his family agreed to laparoscopic heminephrectomy. Preoperatively a right percutaneous nephrostomy was constructed to reduce the hydronephrosis and facilitate the laparoscopic procedure. Under general anesthesia, the patient was placed in the semilateral position on the left side and the body angle was adjusted as required by rotating the operating table. The camera port was positioned at the umbilicus and 3, 10 mm. ports were placed in the midabdominal, pararectal and anterior axillary lines, respectively. Incision on the white line of Toldt and medial reflection of the ascending colon exposed the partly collapsed right part of the horseshoe kidney. Further dissection displayed the right ureter and the isthmus of the horseshoe kidney. The renal vein and artery were isolated and divided between clips, respectively. The supplying artery of the isthmus was not clearly detected, and so the isthmus was divided after coagulation with a microwave coagulator with 80 W. output (part B of figure). NO additional hemostatic technique was needed for the cut surface. After the right ureter was clipped and divided, the kidney was delivered and wrapped in an endoscopic bag. The

Body mass index for chronic hemodialysis patients: Stable hemodialysis and mortality

Abstract Body mass index (BMI) is used as a reference for weight control programs in the general population and in morbidity and mortality studies in diabetes patients. However, the implications of BMI in chronic hemodialysis patients is unclear. We studied the BMI of chronic hemodialysis patients, focusing on problems encountered during outpatient hemodialysis therapy and on 2‐year mortality. Outpatients with chronic hemodialysis (n = 258; 144 men, 114 women) were divided into four groups: (i) patients with stable hemodialysis; (ii) patients with marked hypotension requiring catecholamine infusion during hemodialysis; (iii) patients with excessive interdialysis weight gain requiring occasional additional hemodialysis; and (iv) patients with troublesome hemodialysis due to other causes. The statistical differences between the average BMI among these groups were evaluated, and were subdivided into sex, age and the duration of hemodialysis history. The 2‐year mortality rates of these patients were also studied according to their BMI. In patients under 60 years of age, those with excessive interdialysis weight gain had statistically larger BMI (23.2; n = 35) compared to patients with good hemodialysis control (20.1; n = 178), regardless of gender and hemodialysis history. The mortality rate was at a minimum at approximately 20 BMI in patients under 60 years of age. However, lower BMI was associated with a greater mortality rate in patients 60 years or over. For chronic hemodialysis patients, the BMI associated with stable hemodialysis and minimum mortality is approximately 20, in those under 60 years of age. The BMI of aged hemodialysis patients should be considered separately in morbidity and mortality studies.

Metastatic malignant ameloblastoma of the kidneys

Ameloblastoma is an uncommon disease in the urological field. The resulting tumors or cysts are of odontogenic epithelial origin, are usually benign in nature and rarely metastasize to distant organs. We describe a case of metastatic ameloblastic carcinoma in both kidneys of a 38‐year‐old Japanese man, who had a history of malignant ameloblastoma and was referred to us for evaluation because of gross hematuria and left flank pain. Computed tomography showed irregular cystic masses in both kidneys. After we confirmed that the primary lesion and the lung metastatic lesion had not recurred, we treated the patient surgically. Approximately 4 months postoperatively the patient suffered a local recurrence of tumors that was very invasive and aggressive. The patient died 2 months later and the autopsy showed local metastasis only, without any metastatic lesion in the lungs or other organs. The present case showed that malignant ameloblastoma is highly aggressive, and in the case of metastases the prognosis is usually extremely poor.

Cadmium-induced testicular damage in a rat model of subchronic intoxication

BackgroundCadmium (Cd)-induced testicular damage in relation to spermatogenesis has not been well studied. We studied the mechanism of Cd-induced testicular damage in a rat model of subchronic intoxication.MethodsMale Sprague-Dawley rats were subcutaneously injected with 0.6 mg Cd/kg per day for 6 weeks. The concentration of Cd in urine, serum and testes was measured by using atomic absorption spectrophotometry. Testicular damage was evaluated by counting the spermatogonia (SG) and spermatocytes (SC) on one cut-surface of five seminiferous tubules in stages VII or VIII of spermatogenesis every week. The location of intratesticular cadmium was determined by using oxine-fluorescent cytochemistry.ResultsThere were no differences in the testes/bodyweight ratio between the study and control groups. The concentration of Cd in the testes increased more than 100-fold that in serum after week 2, suggesting active testicular Cd accumulation (1–3 mg/g tissue). Cadmium accumulation was detected in SG and SC. The number of SG and SC diminished significantly in the study group (week 2: SG 74%, SC 90%; week 4: SG 47%, SC 75%; week 6: SG 30%, SC 54% of the control, respectively).ConclusionsCadmium accumulated in SG and SC, consequently reduced the number of these cells, and disturbed the spermatogenesis in this rat model of subchronic Cd intoxication. Therefore, the number of SG decreased in this rat model of subchronic Cd intoxication.

Comparison of Gas‐less laparoscopy‐assisted surgery, hand‐assisted laparoscopic surgery and pure laparoscopic surgery for radical nephrectomy

Background: We report our experience with Gas‐less laparoscopy‐assisted surgery (Gas‐less LAS), hand‐assisted laparoscopic surgery (HALS) and pure laparoscopic surgery (LS) for renal carcinoma and compare the characteristics and usefulness of these methods.

Surgical treatment for an idiopathic renal arteriovenous fistula with a large aneurysm

Abstract Interventional embolization is currently the first line treatment for arteriovenous fistulas; however, the efficacy of repeated embolization remains controversial. A case is reported of an idiopathic renal arteriovenous fistula with large aneurysmal dilatation treated by surgery following the failure of interventional embolization. A 42‐year‐old woman was admitted to Ichikawa General Hospital, Japan, with gross hematuria containing many clots. Right renal arteriogram showed an aberrant vessel arising from the main trunk of the renal artery, which was followed by the formation of an aneurysm and rapidly ended in arteriovenous shunting. The aneurysm was approximately 35mm in size. As interventional embolization had failed, surgical treatment including extracorporeal renal surgery was performed. Postoperative renal angiography revealed excellent renal function and beautiful vascular architecture. Although the indication for surgical treatment of renal vascular disease has decreased owing to the advancement of interventional techniques, there are still some risky cases for which surgical repair should be recommended.

Cavernous hemangioma of the adrenal gland in a patient on chronic hemodialysis.

Cavernous hemangioma of the adrenal gland is rare and most cases are discovered at autopsy. Recently some cases have come to clinical attention as incidental findings on computerized tomography (CT) or magnetic resonance imaging (MRI). However, when a patient is on chronic hemodialysis, it is difficult to make the correct diagnosis because of urogenital organ deformity and the limitations of image enhancement. We report on a patient on chronic hemodialysis

Application of Fluolid-Orange-labeled probes for DNA microarray and immunological assays.

The usefulness of Fluolid-Orange, a novel fluorescent dye, for DNA microarray and immunological assays has been examined. Fluolid-Orange-labeled probes (DNA and IgG) were stable as examined by laser-photo-bleaching and under heat and dry conditions. Statistical analyses were performed to evaluate the reproducibility of the microarray assay, while stage-specific immunostaining of marker proteins, Kank1 and calretinin, was performed for renal cancers, both giving satisfactory results. The stability of the dye should provide advantages for storing fluorescently labeled probes and re-examining the specimens later in genetic and pathological diagnostics.

Prostate cancer with multiple lung metastases in a hemodialysis patient

Abstract In hemodialysis patients, few cases of prostate cancer have been reported until recently. We present a case of prostate cancer with multiple lung metastases in a chronic hemodialysis patient. A 65‐year‐old Japanese man who had maintained hemodialysis for 5 years was referred to our hospital with multiple metastatic lung tumors. Serum prostate tumor markers were highly elevated although his plasma testosterone level was within the normal range. A transrectal needle prostate biopsy confirmed a histologic diagnosis of moderately differentiated adenocarcinoma. Androgen blockade therapy was very effective as evidenced by a quick decrease of serum tumor markers. The follow‐up computed tomography scan of the chest performed 3 months later showed a complete disappearance of the coin lesions. The early detection of prostate cancer in hemodialysis patients is difficult because of a lack of urologic symptoms, which indicate the importance of periodic screening by serum tumor markers. Combined androgen blockade is effective even in hemodialysis patients. However, close follow up is necessary because long‐term results and prognoses are still unknown.