Effect of Phosphate on Nodule Primordia of Soybean (Glycine Max Merrill) in Acid Soils in Rhizotron Experiments

To clarify whether P had a direct or indirect effect on the nodulation process of soybean grown in acid soils from Sitiung, West Sumatra, Indonesia, a series of rhizotron experiments, with special attention given to formation of nodule primordia, was conducted at Laboratory of Microbiology, Wageningen University in 1998-2000. It was shown that Ca and P were essential nutrients for root growth, nodule formation, and growth of soybean in the acid soils (Oxisols). Ca increased root growth, number of nodule primordia, nodules, and growth of the soybean plant. This positive effect of Ca was increased considerably by the application of P. Ca and P have a synergistic effect on biological nitrogen fixation (BNF) of soybean in acid soils. Ca is important for the establishment of nodules, whilst P is essential for the development and function of the formed nodules. P increased number of nodule primordia, thus it also has an important role in the initiation of nodule formation. From this study, it can be concluded that Ca and P are the most limiting nutrients for BNF of soybean in the acid soils of Sitiung, West Sumatra, Indonesia

Characterisation of Soybean Rhizobial Strains From Java and Sumatra

To get insight in the structure of soybean rhizobial population native to Indonesian soils, a thorough survey of the occurrence of the soybean rhizobia were conducted in several locations in Java and Sumatra. A total of 51 different isolates of rhizobial strains were characterised phenotypically based on their symbiotic properties, and genetically using amplified ribosomal DNA restriction analysis (ARDRA). Based on their nodulation capacity on both soybean and the native legume mungbean, these rhizobial strains could be divided into a group of 16 strains specific for soybean only and another group of 35 promiscuous strains that nodulated both leguminous plants. Based on ARDRA of PCRamplified 16S rDNA and 16S-23S rDNA spacer fragments, the rhizobial strains isolated from Java differed with those from Sumatra. Six Java isolates and only one Sumatra isolate were classified as Bradyrhizobium japonicum and these similar to that of B. japonicum strain USDA 110. All these B. japonicum strains were highly specific for soybean. One isolate from Java showed a rather unique position. The remaining strains from Java (20), which were symbiotically promiscuous strains, were clustered in another group. This group and another group containing most Sumatra isolates were distinct from B. japonicum USDA 110 and therefore it is tempting to speculate that these represent indigenous soybean rhizobial bacteria. Application of agricultural practices, such as enhancement of rhizobial population, to increase soybean production is still essential and noteworthy in Sumatra

Intraperitoneal photodynamic therapy of the rat CC531 adenocarcinoma.

The goal of this study was to investigate the efficacy of photodynamic therapy (PDT) of a single tumour growing intraperitoneally. For this purpose the CC531 colon carcinoma, implanted in an intraperitoneal fat pad of Wag/RijA rats, was treated with intraperitoneal photodynamic therapy (IPPDT) using Photofrin as the photosensitiser. Two illumination techniques have been compared. An invasive illumination technique using Perspex blocks to illuminate 30 cm2 of the lower abdomen gave a significant delay in tumour growth with 25 J cm-2 applied 1 day after Photofrin. A minimally invasive illumination technique using a balloon catheter to illuminate 14 cm2 resulted in an equivalent growth delay with 75 J cm-2. The route of administration of the photosensitiser did not influence regrowth times of the tumour. Mitomycin C (MMC), a bioreductive agent, was used to exploit the known PDT-induced hypoxia. The combination of IPPDT with MMC resulted in an increased tumoricidal effect. In conclusion, IPPDT led to a significant growth delay for a single tumour implanted intraperitoneally and repetition of the PDT treatment was possible using a minimally invasive illumination technique. Repeated treatments resulted in increased tumour response

Identification of Stylosanthes guianensis varieties using molecular genetic analysis

Molecular genetic diversity and population structure analysis were used to clarify the controversial botanical classification of Stylosanthes guianensis. The accessions were clustered in nine groups, each of which was mainly composed of only one of the four botanical varieties

Risk of urinary bladder cancer: a case-control analysis of industry and occupation

<p>Abstract</p> <p>Background</p> <p>Uncertainty remains about urinary bladder cancer (UBC) risk for many occupations. Here, we investigate the association between occupation, industry and UBC.</p> <p>Methods</p> <p>Lifetime occupational history was collected by in-person interview for 604 newly diagnosed UBC patients and 604 cancer-free controls. Each job title was assigned a two-digit industry code and a three-digit occupation code. Odds ratios (ORs) for UBC associated with ever being employed in an industry or occupation were calculated by unconditional logistic regression adjusting for age, gender and smoking status. We also examined UBC risk by duration of employment (>0 to <10, ≥10 years) in industry or occupation.</p> <p>Results</p> <p>Significantly increased risk of UBC was observed among waiters and bartenders (OR 2.87; 95% CI 1.05 to 7.72) and occupations related to medicine and health (OR 2.17; 95% CI 1.21 to 3.92), agricultural production, livestock and animal specialties (OR 1.90; 95% CI 1.03 to 3.49), electrical assembly, installation and repair (OR 1.69; 95% CI 1.07 to 2.65), communications (OR 1.74; 95% CI 1.00 to 3.01), and health services (OR 1.58; 95% CI 1.02 to 2.44). For these occupations we also observed a significant excess risk of UBC for long-term work (i.e. ≥10 years), with the exception of waiters and bartenders. Employment for 10 years or more was associated with increased risk of UBC in general farmers (OR 9.58; 95% CI 2.18 to 42.05), agricultural production of crops (OR 3.36; 95% CI 1.10 to 10.27), occupations related to bench working (OR 4.76; 95% CI 1.74 to 13.01), agricultural, fishery, forestry & related (OR 4.58; 95% CI 1.97 to 10.65), transportation equipment (OR 2.68; 95% CI 1.03 to 6.97), and structural work (OR 1.85; 95% CI 1.16 to 2.95).</p> <p>Conclusions</p> <p>This study provides evidence of increased risk of UBC for occupations that were previously reported as at-risk. Workers in several occupation and industry groups have a significantly higher risk of UBC, particularly when duration of employment is 10 years or more.</p