Yukihiko Oishi

Mosaic-Like Structure of Penicillin-Binding Protein 2 Gene (penA) in Clinical Isolates of Neisseria gonorrhoeae with Reduced Susceptibility to Cefixime

ABSTRACT Neisseria gonorrhoeae strains with reduced susceptibility to cefixime (MICs, 0.25 to 0.5 μg/ml) were isolated from male urethritis patients in Tokyo, Japan, in 2000 and 2001. The resistance to cephems including cefixime and penicillin was transferred to a susceptible recipient, N. gonorrhoeae ATCC 19424, by transformation of the penicillin-binding protein 2 gene (penA) that had been amplified by PCR from a strain with reduced susceptibility to cefixime (MIC, 0.5 μg/ml). The sequences of penA in the strains with reduced susceptibilities to cefixime were different from those of other susceptible isolates and did not correspond to the reported N. gonorrhoeae penA gene sequences. Some regions in the transpeptidase-encoding domain in this penA gene were similar to those in the penA genes of Neisseria perflava (N. sicca), Neisseria cinerea, Neisseria flavescens, and Neisseria meningitidis. These results showed that a mosaic-like structure in the penA gene conferred reductions in the levels of susceptibility of N. gonorrhoeae to cephems and penicillin in a manner similar to that found for N. meningitidis and Streptococcus pneumoniae.

Incidence of bone fracture in patients receiving luteinizing hormone-releasing hormone agonists for prostate cancer

Objective To investigate the incidence of bone fractures in patients receiving luteinizing hormone‐releasing hormone agonists (LHRH‐a) for prostate cancer (in whom a continued low testosterone level after the long‐term administration of these drugs reduces bone mineral density), and thus determine the risk of secondary osteoporosis.

Prognostic evaluation of transcatheter arterial embolization for unresectable renal cell carcinoma with distant metastasis.

Objective To evaluate the efficacy of transcatheter arterial embolization (TAE) in patients with unresectable renal cell carcinoma (RCC) and distant metastasis at the time of diagnosis.

Gender as a prognostic factor in patients with renal cell carcinoma

Objective  To evaluate gender as a prognostic factor in patients with renal cell carcinoma (RCC), using a retrospective review of patients with RCC stratified according to gender and analysing factors affecting prognosis.

Prognostic implications of histological features in patients with chromophobe cell renal carcinoma

Objective  To assess the relationship between the histological features of renal chromophobe cell carcinoma (CCC) and clinical outcome in patients with renal cell carcinoma.

Cyst‐associated renal cell carcinoma: Clinicopathologic characteristics and evaluation of prognosis in 27 cases

No consistent clinicopathologic characteristics of cyst‐associated renal cell carcinoma (CRCC) have previously been determined.

Histological features of hypovascular or avascular renal cell carcinoma: the experience at four university hospitals.

AbstractBackground. We aimed to evaluate the pathological features of hypovascular or avascular renal cell carcinoma (RCC), by the retrospective review of the histological features that coincide with hypovascular or avascular RCC. Methods. Seven hundred and ninety-one patients who underwent both preoperative angiography and nephrectomy were examined. Of these patients, the 126 patients (15.9%) who showed hypovascular or avascular angiographic features were selected. Patients with hemorrhage or cyst(s), or with at least 50% necrosis or more in the tumor, and those with renal tumor metastatic to the kidney were excluded. The criteria proposed by the World Health Organization (1998) were adopted for the histological classification. Results. Papillary RCC was the most frequently observed hypovascular or avascular renal tumor (44 cases; 34.9%). The vascularity differed among the variants, i.e., some cases had a basophilic and solid variant with avascular features, while the remaining cases had wide stromal organization showing hypovascular features. The second most frequently observed hyporascular or avascular RCC was chromophobe cell carcinoma (35 cases; 27.8%). No difference in vascularity was detected between variants, except for 2 cases with sarcomatoid changes (avascular features). The third most frequently observed hypovascular or avascular RCC was cyst-associated RCC (29 cases; 23%). All of the 7 RCCs originating in a cyst showed avascular features, and the remaining 22 cystic RCCs showed hypovascular features. The remaining hypovascular or avascular RCCs were cases of clear cell carcinoma accompanied by sarcomatoid changes (8 cases; 6.3%), spindle cell carcinoma (5 cases; 4.0%), and collecting-duct carcinoma (5 cases; 4.0%). Conclusion. Hypovascular or avascular RCC can be categorized as non-clear cell carcinoma and some clear cell carcinoma accompanied by sarcomatoid changes.

Renal metastasis of thyroid carcinoma

We report here the sixth known case of metastatic renal tumor of thyroid carcinoma. In 1999, a 37‐year‐old man was referred to us with a left renal mass found incidentally by ultrasound during an annual check‐up. Computed tomography (CT) revealed a well‐defined, hyperdense mass 3 cm in diameter in the middle of the left kidney. Left radical nephrectomy was performed under the preoperative diagnosis of renal cell carcinoma. Histologically, the tumor was metastatic of typical papillary thyroid carcinoma.

Malignant mesothelioma of testicular tunica vaginalis

We report here a case with malignant mesothelioma of testicular tunica vaginalis. An 81‐year‐old Japanese man with left hydrocele was referred for operation. When hydrocelectomy was performed, a thick wall of tunica vaginalis without malignancy was observed. Seven months after hydrocelectomy, a hard irregular mass was noticed in the left scrotum, therefore inguinal orchiectomy was performed. Pathologically, the mass showed severe atypia and mitosis. The diagnosis of malignant mesothelioma was made. He refused any adjuvant treatment and died 1 year later from multiple metastases to the paraaortic lymph nodes and lumbar supine.

黄体化ホルモン放出ホルモン誘導体 (LHRH-a) による骨量低下の臨床的検討

BACKGROUND It is well known that androgens play an important role in bone metabolism and male hypogonadism induce osteoporosis. Luteinizing hormone-releasing hormone analogue (LHRH-a) which is essential for conservative therapy of prostatic carcinoma (CaP) ultimately reduces circulating testosterone to castration levels. The purpose of this study was to determine the risk of decrease of bone mineral density in men receiving LHRH-a for CaP. PATIENTS AND METHODS Fifty-three man with CaP aged 63 to 95 years (mean 75.5 years) were included in this study. Seven patients received LHRH-a with estrogen drug, forty-six patients received LHRH-a with or without anti androgen drug. To estimate patients bone density we use the second metacarpal bone density using a microdensitometry method. RESULTS Blood level of sex hormone of the forty-six patients who were received LHRH-a without estrogen, was the same as that of castration. Patients who were treated more than twelve months had less bone density than patients who were treated less than eleven months. As the duration of medical castration period was prolonged, patients bone density were reduced. Whereas seven patients who received estrogen drug did not find a decrease of bone density regardless of duration of treatment period. CONCLUSIONS Hypogonadism induced LHRH-a also reduce bone density, so there is a risk of iatrogenic osteoporosis caused by therapy for CaP with LHRH-a. Patients with osteoporosis easily suffer from a much complicated and pernicious bone fracture, so we should measure bone density of male patients same as female treated with LHRH-a for a long-term.