Soil productivity and structure of bacterial and fungal communities in unfertilized arable soil.

Soil productivity is strongly influenced by the activities of microbial communities. However, it is not well understood how community structure, including its richness, mass, and composition, influences soil functions. We investigated the relationships between soil productivity and microbial communities in unfertilized arable soils extending over 1000 km in eastern Japan. Soil properties, including C turnover rate, N mineralization rate, microbial C, and various soil chemical properties, were measured. Soil bacterial and fungal communities were analyzed by Illumina's MiSeq using 16S rRNA and ITS regions. In addition, root microbial communities from maize grown in each soil were also investigated. Soil bacterial communities shared many operational taxonomic units (OTUs) among farms. An ordination plot based on correspondence analysis revealed convergent distribution of soil bacterial communities across the farms, which seemed to be a result of similar agricultural management practices. Although fungal communities showed lower richness and a lower proportion of shared OTUs than bacterial communities, community structure between the farms tended to be convergent. On the other hand, root communities had lower richness and a higher abundance of specific taxa than the soil communities. Two soil functions, decomposition activity and soil productivity, were extracted by principal component analysis (PCA) based on eight soil properties. Soil productivity correlated with N mineralization rate, P2O5, and maize growth, but not with decomposition activity, which is characterized by C turnover rate, soil organic C, and microbial mass. Soil productivity showed a significant association with community composition, but not with richness and mass of soil microbial communities. Soil productivity also correlated with the abundance of several specific taxa, both in bacteria and fungi. Root communities did not show any clear correlations with soil productivity. These results demonstrate that community composition and abundance of soil microbial communities play important roles in determining soil productivity.

[Clinico-statistical analysis of renal cell carcinomas in patients on hemodialysis].

Eleven patients on hemodialysis that were surgically treated for renal cell carcinomas during the recent 10 years at our institutes were clinically analyzed. Patients' ages at presentation ranged from 35 to 70 years with an average of 54.8 years. Nine of the 11 patients were males and 2 were females. Periods between the introduction of hemodialysis and the presentation ranged from 1 to 21 years with an average of 11.7 years. The most frequent cause of hemodialysis was chronic glomerulonephritis. Five patients presented with macroscopic hematuria, which was the most frequent clinical manifestation. Transperitoneal nephrectomy through a lumbar oblique incision was performed in 9 of 12 surgical procedures. Transperitoneal resection and retroperitoneal endoscopic resection were performed on 2 patients and 1 patient, respectively. Blood transfusion was performed on 2 patients with retroperitoneal hemorrhage before or after operation and 2 patients with pre-existing renal anemia. Pathologically, 9 patients had pT1a disease. Patients were followed up for up to 7 years and 11 months. One patient died of the disease and 2 patients died of unknown causes. In conclusion, surgical removal of renal cell carcinomas was well tolerated, safe and effective treatment in patients under hemodialysis.

Germ cell apoptosis in undescended testis: the origin of its impaired spermatogenesis in the TS inbred rat.

PURPOSE: Undescended testis is one of the most important congenital anomalies in male urogenital organs that may cause male infertility. We examined the process of spermatogenesis of TS inbred rats, of which approximately 70% of male newborns have congenital undescended testes. MATERIALS AND METHODS: Unilaterally affected animals at ages 4, 6 and 8 weeks were analyzed in this study. Histopathological evaluation of spermatogenesis was performed by periodic acid-Schiff-hematoxylin staining. To elucidate the pathophysiology of seminiferous tubule damage germ cell apoptosis was assessed by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling and electron microscopy. Four animals per group were used for staining and nick end-labeling. RESULTS: Testicular weight significantly decreased on the affected side at ages 6 and 8 weeks. Impaired spermatogenesis was observed as early as age 4 weeks. Germ cell apoptosis was significantly more frequent on the affected side in all age groups with the most prominent incidence at age 6 weeks. Most apoptotic germ cells were considered spermatocytes. Electron microscopy revealed apoptosis of spermatocytes with condensation of chromatins and agglutination of cytoplasmic contents. CONCLUSIONS: This study suggests the efficacy of early intervention in patients with undescended testes.