Search

Cultivated sunflower (Helianthus annuus) is the fourth most important oilseed crop globally and is known to have experienced multiple genetic bottlenecks during domestication and improvement. Homogenization of crop germplasm may limit breeding efforts to improve pest and pathogen resistance or optimize other biotic interactions like pollinator attraction. Such interactions are often strongly influenced by plant phytochemistry, especially volatile compounds like terpenoids. Here we use solid-phase microextraction gas chromatography mass spectrometry (SPME GC-MS) to evaluate volatile phytochemistry across leaves, involucral bracts, disc florets, and ray floret petals in a collection of twelve inbred lines selected to represent a cross-section of sunflower germplasm diversity. Results indicate considerable compositional diversity of volatiles among lines, though substantial reduction in total volatile abundance relative to wild H. annuus. From leaves and bracts to disc florets and petals, we observe a strong increase in the proportion of monoterpenoids relative to sesquiterpenoids accompanying the transition to reproductive structures, with consistently over 85% monoterpenoids in disc florets and petals. This pattern is driven by substantially higher production of monoterpenoids (especially alpha-pinene and sabinene) in reproductive structures. Sesquiterpenoid production is roughly similar across organs, and in leaves varies among lines from 21-55% of volatiles, dominated by cadinene-type sesquiterpenoids. This work suggests that the compositional diversity of volatile terpenoids within cultivated germplasm may be sufficient for many breeding applications, though for breeding increased volatile production the use of wild H. annuus and other wild Helianthus germplasm may be necessary. [ABSTRACT FROM AUTHOR]

OBJECTIVE: This prospective, double-blind, multicenter, parallel-group study compared the efficacy and safety of therapeutic doses of clozapine and risperidone in patients with severe chronic schizophrenia and poor previous treatment response. METHOD: Male or female patients aged 18-65 years who met DSM-IV criteria for schizophrenia and study requirements for poor previous treatment response (N=273) were randomly assigned to double-blind treatment with either clozapine or risperidone administered over 12 weeks in increasing increments. The primary efficacy measures were the magnitude of improvement in Brief Psychiatric Rating Scale (BPRS) and Clinical Global Impression (CGI) scores. Adverse events were recorded throughout the study. RESULTS: The magnitude of improvement in mean BPRS and CGI scores from baseline to end of the study was significantly greater in the clozapine group than in the risperidone group. Statistically significant differences in favor of clozapine were also seen for most of the secondary efficacy measures (Positive and Negative Syndrome Scale, Calgary Depression Scale, Psychotic Depression Scale, and Psychotic Anxiety Scale). The adverse event profile was similar for both treatment groups, with a lower risk of extrapyramidal symptoms in the clozapine group. CONCLUSIONS: Clozapine showed superior efficacy over risperidone in this patient population. Both treatments were equally well tolerated as demonstrated through their adverse event profiles, although as expected clozapine was associated with a lower risk of extrapyramidal symptoms than risperidone. [ABSTRACT FROM AUTHOR]

- Two hundred and nine patients with biopsy-proven stage D2 prostatic carcinoma showing disease progression after orchiectomy or treatment with DES (stilboestrol) or an LHRH agonist alone received combination therapy with the pure antiandrogen flutamide. In patients treated with DES, the oestrogen was replaced by the LHRH agonist [D-Trp6]LHRH ethylamide. The objective response to therapy was assessed according to the criteria of the US NPCP. Thirteen patients had a complete response to treatment, while partial and stable responses were achieved in 20 and 39 patients respectively (total objective response rate of 34.5%). The mean duration of response was 24 months. In the non-responders the median survival was 8.1 months with a 17% probability of survival at 2 years; the probabilities of survival at 2 years of the patients who showed partial and stable responses were 87 and 67% respectively. All patients who achieved a complete response are still alive. Combination therapy with Flutamide and castration (surgical or LHRH agonist) appears to be the treatment of choice for prostate cancer patients in relapse after standard endocrine therapy. [ABSTRACT FROM AUTHOR]

Health Canada has been collecting data on Inuit and First Nations' methylmercury (MeHg) levels for 25 years. A national overview has beencompleted and more focussed analyses have now been initiated. This paper deals with two interdependent analytical components: 1) a longitudinal overview of the two most extensively sampled communities in Canada: Grassy Narrows and Whitedog, the residents of which were exposed to 'point source' mercury pollution in the 1970's; 2) fetal and post-natal exposure to mercury in these two communities including an outline of the First Nation MeHg child development pilot project in the two communities. A retrospective analysis of Grassy Narrows and Whitedog shows a decreasing MeHg trend in both communities. In Grassy Narrows the average individual annual peak methylmercury level in blood has decreased significantly, from 23.80 ppb (range 1.50-- 322.90) in 1976 to 7.5 ppb (1.7--46.7) in 1995 (r= -0.65, p<0.001). In Whitedog the average peak has also decreased significantly, from 12.87 ppb (1.50--172.00) in 1976 to 6.1 ppb (1.7--33.3) in 1995 (r= -0.59, P<0.005). However, behind these positive trends is the reality of two communities still suffering the effects of disrupted lifestyles and socio-cultural damage. A number of cord blood samples, maternal blood samples, and samples from women of child-bearing age from these communities have been in the 'risk' group (according to the 1990 WHO guidelines).We are therefore now assessing the long term effects of fetal exposure in the communities. Standard clinical examinations in the past failed to prove abnormalities attributable to methylmercury but did not include subtle neuropsychological development tests. Many of the fetally exposed children are now in secondary school. Therefore, we have initiated a pilot project to assess long term effects of methylmercury exposure on the neuropsychological development of these children whose fetal exposure we know. The pilot child development project whichwa [ABSTRACT FROM AUTHOR]