Receptors: localization and specificity of binding of serotonin in the central nervous system

Formation of a Schiff base between the ethylamine residue of serotonin and an appropriate carbonyl residue at the receptor site may be among the forces holding serotonin onto the receptor. Reduction of this imine may provide a means of permanently labeling receptors as a preliminary to their isolation.     

SEPTIC COXOFEMORAL ARTHRITIS AND OSTEOMYELITIS IN A DOG

An 8-year-old male Labrador retriever presented with a rear limb lameness cased by an osteolytic lesion of the left acetabulum and femoral head and neck. Initial bone biopsy study was nondiagnostic. Histopathologic study and culture of the subsequently excised femoral head and neck revealed a Staphyloccocus intermedial arthritis and osteomyelitis. Neoplash was ruled out on the basis of histopathologic analysis.     

Development and validation of a short questionnaire to assess sodium intake

OBJECTIVES: To develop and validate a short food-frequency questionnaire to assess habitual dietary salt intake in South Africans and to allow classification of individuals according to intakes above or below the maximum recommended intake of 6 g salt day-1. DESIGN: Cross-sectional validation study in 324 conveniently sampled men and women. METHODS: Repeated 24-hour urinary Na values and 24-hour dietary recalls were obtained on three occasions. Food items consumed by >5% of the sample and which contributed > or =50 mg Na serving-1 were included in the questionnaire in 42 categories. A scoring system was devised, based on Na content of one index food per category and frequency of consumption. RESULTS: Positive correlations were found between Na content of 35 of the 42 food categories in the questionnaire and total Na intake, calculated from 24-hour recall data. Total Na content of the questionnaire was associated with Na estimations from 24-hour recall data (r = 0.750; P < 0.0001; n = 328) and urinary Na (r = 0.152; P = 0.0105; n = 284). Urinary Na was higher for subjects in tertile 3 than tertile 1 of questionnaire Na content (P < 0.05). Questionnaire Na content of <2400 and > or =2400 mg day-1 equated to a reference cut-off score of 48 and corresponded to mean (standard deviation) urinary Na values of 145 (68) and 176 (99) mmol day-1, respectively (P < 0.05). Sensitivity and specificity against urinary Na > or =100 and <100 mmol day-1 was 12.4% and 93.9%, respectively. CONCLUSION: A 42-item food-frequency questionnaire has been shown to have content-, construct- and criterion-related validity, as well as internal consistency, with regard to categorising individuals according to their habitual salt intake; however, the devised scoring system needs to show improved sensitivity.     

Characterization of Acidovorax citrulli strains isolated from solanaceous plants

Acidovorax citrulli is the causal agent of bacterial fruit blotch disease of cucurbits. Strains of this pathogen are distributed into two major groups: Group I strains have been mainly isolated from melon and other non-watermelon cucurbits, while Group II strains have been mainly recovered from watermelon. Here we report the characterization of strains T1 and EP isolated from diseased tomato and eggplant plants, respectively, and further confirmed to belong to A. citrulli species. Based on PCR, PFGE, and rep-PCR, these strains showed high similarity to the Group II strain 7a1. Sequencing and comparative analyses revealed that the genomes of T1 and EP aligned with that of the Group II model strain AAC00-1, over 97.88% and 99.22%, respectively. The virulence of T1, EP, and 7a1 determined on tomato, eggplant, and watermelon was similar and significantly higher than that of Group I strain M6. In contrast, M6 was more virulent on melon. Expression levels of seven virulence genes measured 24 hr after inoculation of tomato, eggplant, watermelon, and melon showed that the expression pattern was generally similar in strains 7a1, T1, and EP, whereas for M6 the expression was high only on melon. Overall, our results indicate that the solanaceous strains belong to Group II. To the best of our knowledge, this is the first study that reports characterization of A. citrulli strains isolated from solanaceous species. The fact that A. citrulli is able to naturally colonize and cause disease in non-cucurbit crops poses additional challenges for management of this important pathogen.     

Characterization of Pectobacterium brasiliense strains from potato and vegetables in Israel

Pectobacterium brasiliense (Pbr) infects a wide range of crops worldwide, causing potato blackleg and soft rot and vegetable soft rots. This study aimed to characterize the genetic diversity and virulence variability among 68 Pbr strains isolated from either symptomless potato progeny tubers, diseased potato plants, ware potatoes wash water, or vegetables grown in Israel, as well as strains isolated from symptomless seed tubers grown in Europe, or diseased potato plants grown in France. The collection was typed using PCR and TaqMan real-time PCR analyses, dnaX sequence analysis, pulsed-field gel electrophoresis (PFGE), and pectolytic activity. dnaX phylogeny grouped almost all strains in a common genetic clade related to Pbr, which was distinct from the other Pectobacterium species. PFGE analysis identified two main clusters, including one major group of 47 strains with 95%–100% similarity. Maceration assays on two potato cultivars showed significant differences between strains but with no correlations with the source of the strains nor the status of the host (with/without symptoms). Molecular (dnaX sequences and PFGE profiles) and phenotypic analyses (tuber maceration tests) showed that the tested Pbr strains are not a homogeneous group. Analysis of the tested Pbr strains isolated from potato and vegetables grown in fields with a history of potato cultivation suggests that seed tubers imported from Europe may be the main source for Pbr in Israel. To the best of our knowledge, this is the first study that describes biodiversity and population structure of P. brasiliense isolated from potato and vegetables under hot climate conditions.     

Effect of Nutrition on Deformation Disease in Gypsophila paniculata Mother Plants

ABSTRACT Deformation disease of Gypsophila paniculata mother plants reduces cutting yields as much as 50% but does not kill the mother plants. In preliminary experiments, fertigation of G. paniculata mother plants with a 20:20:20 compound fertilizer (N, P, K, plus microelements) at an N concentration of 720 mg/liter reduced the expression of deformation disease compared with the conventional N concentration of 360 mg/liter. The current study determined which component of the compound fertilizer reduced the disease. Experiments were carried out in 10-liter buckets packed with naturally infested 0- to 8-mm black tuff (Scoria = crushed volcanic stones). Irrigation was applied once a day at 0.5 liter per bucket with the nutrient under test being added at 1.0 liter per bucket via the water once a week. Treatments included: (i) four levels of 20:20:20 fertilizer; (ii) four levels of each of N, P, K, and Fe-Zn-Mn mixture (ME) corresponding to their concentrations in the compound fertilizer; (iii) different N sources (20:20:20, (NH(4))(2)SO(4), KNO(3), NH(4)NO(3), urea); and (iv) three pHs of the irrigation water at each of three NO(3) and NH(4) application levels. Increasing the 20:20:20 fertilizer concentration reduced the disease level from 82 to 96% with N at 180 mg/liter to 6 to 10% with N at 720 mg/liter. When either P, K, or ME was the sole variable, increasing concentrations had no significant effect on the disease, but elevating a mixed source nitrogen concentration from 0 to 180, 360, and 720 mg/liter (as 50% urea, 40% NH(4)NO(3), and 10% KNO(3)) significantly reduced deformation similar to that observed with increasing concentrations of the 20:20:20 fertilizer. mong tested N sources, NH(4) was the most effective in reducing the disease (almost to zero at an N concentration of 360 g/liter). Low disease incidence (0 to 10%) was always associated with effluent pH of 6 or lower. Irrigating with acidified water pH 5.5) in the presence of N, as NH(4) at 180 mg/liter, additionally reduced disease from 56% under tap water (pH 7.8) rrigation to 11%. Similar acidification in the presence of NO (-) (3) N at 180 mg/liter was ineffective in reducing the disease, but ater basification in the presence of NO (-) (3) N reduced disease incidence from 93 to 38% 90 days after planting. The N, P, K, Fe, and Zn concentrations in gypsophila cuttings were similar under the three tested levels of NH(4), NO(3), and 20:20:20, whereas the concentration of Mn increased with increasing N. The Mn concentration in cuttings was inversely correlated with disease and is probably an important factor to understanding the physiological background of the deformation disease.