Peter H. Graham

Legumes: importance and constraints to greater use.

Legumes, broadly defined by their unusual flower structure, podded fruit, and the ability of 88% of the species examined to date to form nodules with rhizobia ([de Faria et al., 1989][1]), are second only to the Graminiae in their importance to humans. The 670 to 750 genera and 18,000 to 19,000

Rhizobium tropici, a Novel Species Nodulating Phaseolus vulgaris L. Beans and Leucaena sp. Trees

A new Rhizobium species that nodulates Phaseolus vulgaris L. and Leucaena spp. is proposed on the basis of the results of multilocus enzyme electrophoresis, DNA-DNA hybridization, an analysis of ribosomal DNA organization, a sequence analysis of 16S rDNA, and an analysis of phenotypic characteristics. This taxon, Rhizobium tropici sp. nov., was previously named Rhizobium leguminosarum biovar phaseoli (type II strains) and was recognized by its host range (which includes Leucaena spp.) and nif gene organization. In contrast to R. leguminosarum biovar phaseoli, R. tropici strains tolerate high temperatures and high levels of acidity in culture and are symbiotically more stable. We identified two subgroups within R. tropici and describe them in this paper.

Common bean (Phaseolus vulgaris L.)

Abstract This paper reviews the origins and general botany of Phaseolus vulgaris , the different cropping systems used for bean production, the agronomic and biological factors which most limit crop yield, and the strategies for improvement in this crop. While the common bean originated in the Americas, it is now grown widely in both the old- and the new world and in Africa, with the most suitable ideotype, and the disease and insect resistance factors needed for a particular production area, dependent on local conditions. Marked color and seed-type preferences further complicate the breeding and adoption of new varieties. The paper considers both conventional approaches and marker-assisted methods for breeding in this crop. The common bean is a crop with multiple disease and insect pests, and the ability to quickly and effectively select plants carrying multiple or different types of resistance gene is essential to an orderly and efficient processing of progeny.

Nitrogen fixation in perspective: an overview of research and extension needs.

Abstract Recent reports point to a decline in agricultural dependence on symbiotic nitrogen (N 2 ) fixation, and in the use of rhizobial inoculants. This review contrasts the potential contribution of biologically fixed N to intensive and extensive agricultural systems, and examines opportunities for continued major contributions in the latter. It identifies six research and extension areas in which in-depth efforts are still needed, and examines some opportunities for improved N 2 fixation likely to arise through advances in molecular biology.

Prediction of Local Recurrence, Distant Metastases, and Death After Breast-Conserving Therapy in Early-Stage Invasive Breast Cancer Using a Five-Biomarker Panel

PURPOSE To determine the clinical utility of intrinsic molecular phenotype after breast-conserving therapy (BCT) with lumpectomy and whole-breast irradiation with or without a cavity boost. PATIENTS AND METHODS Four hundred ninety-eight patients with invasive breast cancer were enrolled into a randomized trial of BCT with or without a tumor bed radiation boost. Tumors were classified by intrinsic molecular phenotype as luminal A or B, HER-2, basal-like, or unclassified using a five-biomarker panel: estrogen receptor, progesterone receptor, HER-2, CK5/6, and epidermal growth factor receptor. Kaplan-Meier and Cox proportional hazards methodology were used to ascertain relationships to ipsilateral breast tumor recurrence (IBTR), locoregional recurrence (LRR), distant disease-free survival (DDFS), and death from breast cancer. RESULTS Median follow-up was 84 months. Three hundred ninety-four patients were classified as luminal A, 23 were luminal B, 52 were basal, 13 were HER-2, and 16 were unclassified. There were 24 IBTR (4.8%), 35 LRR (7%), 47 distant metastases (9.4%), and 37 breast cancer deaths (7.4%). The overall 5-year disease-free rates for the whole cohort were: IBTR 97.4%, LRR 95.6%, DDFS 92.9%, and breast cancer-specific death 96.3%. A significant difference was observed for survival between subtypes for LRR (P = .012), DDFS (P = .0035), and breast cancer-specific death (P = .0482), but not for IBTR (P = .346). CONCLUSION The 5-year and 10-year survival rates varied according to molecular subtype. Although this approach provides additional information to predict time to IBTR, LRR, DDFS, and death from breast cancer, its predictive power is less than that of traditional pathologic indices. This information may be useful in discussing outcomes and planning management with patients after BCT.

Proposed Minimal Standards for the Description of New Genera and Species of Root- and Stem-Nodulating Bacteria

Since the first volume of Bergeys Manual of Systematic Bacteriology was published, in 1984, two additional genera and several new species of stem- and root-nodulating bacteria have been proposed; further changes to the taxonomy of this group of organisms appear likely. This paper briefly reviews the current status of “Rhizobium” taxonomy and proposes minimal standards for the description of future genera and species belonging to this group of organisms.

Diagnostic features in the characterisation of the root-nodule bacteria of legumes

To resolve taxonomic difficulties within the genus Rhizobium L a n g e is suggested the derivation of a variety of tests by which the root-nodule bacteria could be characterised, and the use of these tests in the comparison of strains by computer analysis. 26 Routine identification of strains by this method is impracticable for many Rhizobium research workers. On the other hand, infective properties alone frequently fail to give adequate differentiation of the species of root-nodule bacteria a 18 21 g8 The results obtained from a computative classification of the root-nodule bacteria were used by G r a h a m 9 to propose taxonomic changes in the genus Rhizobium. It was apparent that some currently favoured diagnostic features were of less value in rhizobial classification than other characters which are not normally considered An assessment of these features, and of other properties of the rootnodule bacteria is reported in this paper.

Acquisition of epithelial-mesenchymal transition and cancer stem cell phenotypes is associated with activation of the PI3K/Akt/mTOR pathway in prostate cancer radioresistance.

Radioresistance is a major challenge in prostate cancer (CaP) radiotherapy (RT). In this study, we investigated the role and association of epithelial–mesenchymal transition (EMT), cancer stem cells (CSCs) and the PI3K/Akt/mTOR signaling pathway in CaP radioresistance. We developed three novel CaP radioresistant (RR) cell lines (PC-3RR, DU145RR and LNCaPRR) by radiation treatment and confirmed their radioresistance using a clonogenic survival assay. Compared with untreated CaP-control cells, the CaP-RR cells had increased colony formation, invasion ability and spheroid formation capability (P<0.05). In addition, enhanced EMT/CSC phenotypes and activation of the checkpoint proteins (Chk1 and Chk2) and the PI3K/Akt/mTOR signaling pathway proteins were also found in CaP-RR cells using immunofluorescence, western blotting and quantitative real-time PCR (qRT-PCR). Furthermore, combination of a dual PI3K/mTOR inhibitor (BEZ235) with RT effectively increased radiosensitivity and induced more apoptosis in CaP-RR cells, concomitantly correlated with the reduced expression of EMT/CSC markers and the PI3K/Akt/mTOR signaling pathway proteins compared with RT alone. Our findings indicate that CaP radioresistance is associated with EMT and enhanced CSC phenotypes via activation of the PI3K/Akt/mTOR signaling pathway, and that the combination of BEZ235 with RT is a promising modality to overcome radioresistance in the treatment of CaP. This combination approach warrants future in vivo animal study and clinical trials.

Inhalation Aromatherapy During Radiotherapy: Results of a Placebo-Controlled Double-Blind Randomized Trial

PURPOSE To determine whether the inhalation of aromatherapy during radiotherapy reduces anxiety. PATIENTS AND METHODS Three hundred thirteen patients undergoing radiotherapy were randomly assigned to receive either carrier oil with fractionated oils, carrier oil only, or pure essential oils of lavender, bergamot, and cedarwood administered by inhalation concurrently with radiation treatment. Patients underwent assessment by the Hospital Anxiety and Depression Scale (HADS) and the Somatic and Psychological Health Report (SPHERE) at baseline and at treatment completion. RESULTS There were no significant differences in HADS depression or SPHERE scores between the randomly assigned groups. However, HADS anxiety scores were significantly lower at treatment completion in the carrier oil only group compared with either of the fragrant arms (P =.04). CONCLUSION Aromatherapy, as administered in this study, is not beneficial.

MicroRNA expression profile in common bean (Phaseolus vulgaris) under nutrient deficiency stresses and manganese toxicity.

*MicroRNAs (miRNAs) play a pivotal role in post-transcriptional regulation of gene expression in plants. Information on miRNAs in legumes is as yet scarce. This work investigates miRNAs in an agronomically important legume, common bean (Phaseolus vulgaris). *A hybridization approach employing miRNA macroarrays - printed with oligonucleotides complementary to 68 known miRNAs - was used to detect miRNAs in the leaves, roots and nodules of control and nutrient-stressed (phosphorus, nitrogen, or iron deficiency; acidic pH; and manganese toxicity) common bean plants. *Thirty-three miRNAs were expressed in control plants and another five were only expressed under stress conditions. The miRNA expression ratios (stress:control) were evaluated using principal component and hierarchical cluster analyses. A group of miRNAs responded to nearly all stresses in the three organs analyzed. Other miRNAs showed organ-specific responses. Most of the nodule-responsive miRNAs showed up-regulation. miRNA blot expression analysis confirmed the macroarray results. Novel miRNA target genes were proposed for common bean and the expression of selected targets was evaluated by quantitative reverse transcriptase-polymerase chain reaction. *In addition to the detection of previously reported stress-responsive miRNAs, we discovered novel common bean stress-responsive miRNAs, for manganese toxicity. Our data provide a foundation for evaluating the individual roles of miRNAs in common bean.