Temperatures and qualities of light in Niger (Guizotia abyssinica (L.f.) Cass.) seeds germination in Mato Grosso do Sul, Brazil

For each vegetable species, there is a specific environment conditions to occur the seed germination process. However, there is a little information regarding the necessary conditions for Niger (Guizotia abyssinica (L.f.) Cass.) seeds germination. The aim of this research was to evaluate the influence of different temperatures and types of light on Niger (Guizotia abyssinica (L.f.) Cass.) seeds germination. Seeds were sown on two sheets of “germitest” paper inside plastic box type “gerbox” and placed on B.O.D. Treatments were constituted of two constant temperatures (15 ºC and 25 ºC, respectively) and an alternating temperature (20-30 ºC) under 10 hours for the lowest temperature and 14 hours for the highest temperature and they were associated to the wavelengths as follows: blue (440 nm), green (560 nm), red (660 nm), extreme red (730 nm), white light and dark. The experiment was conducted in a completely randomized design with four replicates of 50 seeds. Effects of different temperatures and qualities of light were evaluated by seeds germination and vigor. Higher germination of Niger seeds is observed in temperatures of 25 and 20-30 ºC and they can be considered as non-photoblastic.For each vegetable species, there is a specific environment conditions to occur the seed germination process. However, there is a little information regarding the necessary conditions for Niger (Guizotia abyssinica (L.f.) Cass.) seeds germination. The aim of this research was to evaluate the influence of different temperatures and types of light on Niger (Guizotia abyssinica (L.f.) Cass.) seeds germination. Seeds were sown on two sheets of “germitest” paper inside plastic box type “gerbox” and placed on B.O.D. Treatments were constituted of two constant temperatures (15 ºC and 25 ºC, respectively) and an alternating temperature (20-30 ºC) under 10 hours for the lowest temperature and 14 hours for the highest temperature and they were associated to the wavelengths as follows: blue (440 nm), green (560 nm), red (660 nm), extreme red (730 nm), white light and dark. The experiment was conducted in a completely randomized design with four replicates of 50 seeds. Effects of different temperatures and qualities of light were evaluated by seeds germination and vigor. Higher germination of Niger seeds is observed in temperatures of 25 and 20-30 ºC and they can be considered as non-photoblastic

Substrate water availability and seed water content on niger germination

Niger is an oleaginous species whose cultivation has been spreading, but there is not much information on the adverse conditions during its seedling establishment. This study aimed at evaluating the effects of substrate water availability and seed water content on niger germination. Seeds were moistened using the humid atmosphere method for 0; 24; 48; and 72 hours, obtaining the water contents of 7.0 %, 12.8 %, 16.8 % and 32.2 %. Then, they were sown in substrate moistened with PEG 6000 solutions with different osmotic potentials: 0.0 MPa (control), -0.1 MPa, -0.2 MPa, -0.3 MPa and -0.4 MPa. A completely randomized design, in a 4 x 5 factorial scheme (water content x osmotic potential), with four replications of 50 seeds, was used. First count and germination percentage, germination speed index and mean time, shoot and root length and seedlings dry weight were evaluated. The reduction in the substrate osmotic potential decreases the niger seed germination and seedling growth, regardless of water content, but with a higher evidence in seed water contents below 32.2 % and 12.8 %, respectively

PCR colorimetric dot-blot assay and clinical pretest probability for diagnosis of Pulmonary Tuberculosis in Smear-Negative patients

<p>Abstract</p> <p>Background</p> <p>Smear-negative pulmonary tuberculosis (SNPTB) accounts for 30% of Pulmonary Tuberculosis (PTB) cases reported annually in developing nations. Polymerase chain reaction (PCR) may provide an alternative for the rapid detection of <it>Mycobacterium tuberculosis </it>(MTB); however little data are available regarding the clinical utility of PCR in SNPTB, in a setting with a high burden of TB/HIV co-infection.</p> <p>Methods</p> <p>To evaluate the performance of the PCR dot-blot in parallel with pretest probability (Clinical Suspicion) in patients suspected of having SNPTB, a prospective study of 213 individuals with clinical and radiological suspicion of SNPTB was carried out from May 2003 to May 2004, in a TB/HIV reference hospital. Respiratory specialists estimated the pretest probability of active disease into high, intermediate, low categories. Expectorated sputum was examined by direct microscopy (Ziehl-Neelsen staining), culture (Lowenstein Jensen) and PCR dot-blot. Gold standard was based on culture positivity combined with the clinical definition of PTB.</p> <p>Results</p> <p>In smear-negative and HIV subjects, active PTB was diagnosed in 28.4% (43/151) and 42.2% (19/45), respectively. In the high, intermediate and low pretest probability categories active PTB was diagnosed in 67.4% (31/46), 24% (6/25), 7.5% (6/80), respectively. PCR had sensitivity of 65% (CI 95%: 50%–78%) and specificity of 83% (CI 95%: 75%–89%). There was no difference in the sensitivity of PCR in relation to HIV status. PCR sensitivity and specificity among non-previously TB treated and those treated in the past were, respectively: 69%, 43%, 85% and 80%. The high pretest probability, when used as a diagnostic test, had sensitivity of 72% (CI 95%:57%–84%) and specificity of 86% (CI 95%:78%–92%). Using the PCR dot-blot in parallel with high pretest probability as a diagnostic test, sensitivity, specificity, positive and negative predictive values were: 90%, 71%, 75%, and 88%, respectively. Among non-previously TB treated and HIV subjects, this approach had sensitivity, specificity, positive and negative predictive values of 91%, 79%, 81%, 90%, and 90%, 65%, 72%, 88%, respectively.</p> <p>Conclusion</p> <p>PCR dot-blot associated with a high clinical suspicion may provide an important contribution to the diagnosis of SNPTB mainly in patients that have not been previously treated attended at a TB/HIV reference hospital.</p

New genetic loci link adipose and insulin biology to body fat distribution.

Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms

Teste de deterioração controlada em sementes de niger (Guizotia abyssinica (L.f.) Cass.)

O niger (Guizotia abyssinica (L.f.) Cass.) &eacute; uma esp&eacute;cie oleaginosa promissora para a produ&ccedil;&atilde;o de biodiesel; entretanto, possui poucas informa&ccedil;&otilde;es a respeito da avalia&ccedil;&atilde;o do potencial fisiol&oacute;gico de suas sementes. Assim, objetivou-se adaptar a metodologia do teste de deteriora&ccedil;&atilde;o controlada para avaliar seus efeitos sobre as sementes de niger. Foram utilizados seis lotes de sementes, inicialmente caracterizados quanto ao grau de umidade, porcentagem de germina&ccedil;&atilde;o, primeira contagem de germina&ccedil;&atilde;o, &iacute;ndice de velocidade germina&ccedil;&atilde;o, tempo m&eacute;dio de germina&ccedil;&atilde;o, porcentagem de emerg&ecirc;ncia, &iacute;ndice de velocidade de emerg&ecirc;ncia, tempo m&eacute;dio de emerg&ecirc;ncia; estande inicial de pl&acirc;ntulas e crescimento inicial de pl&acirc;ntulas. No teste de deteriora&ccedil;&atilde;o controlada as sementes tiveram o conte&uacute;do de &aacute;gua ajustado para 16, 20 e 24%, sendo ent&atilde;o submetidas a temperatura de 41&deg;C por per&iacute;odos de 24 e 48 h. Ap&oacute;s o per&iacute;odo de deteriora&ccedil;&atilde;o, as sementes foram submetidas ao teste de germina&ccedil;&atilde;o e procedeu-se a avalia&ccedil;&atilde;o aos 7 d ap&oacute;s a semeadura, contabilizando-se a porcentagem de pl&acirc;ntulas normais. O delineamento experimental utilizado foi o inteiramente casualizado com quatro repeti&ccedil;&otilde;es de 50 sementes. O teste de deteriora&ccedil;&atilde;o controlada &eacute; eficiente para a avalia&ccedil;&atilde;o do potencial fisiol&oacute;gico das sementes de niger e correlaciona-se positivamente com o teste de emerg&ecirc;ncia de pl&acirc;ntulas, sendo a combina&ccedil;&atilde;o de 16% de teor de &aacute;gua das sementes e 24 h de exposi&ccedil;&atilde;o a mais adequada para a avalia&ccedil;&atilde;o do potencial fisiol&oacute;gico das sementes de niger.&nbsp;ABSTRACT Niger (Guizotia abyssinica (L.f.) Cass.) is a promising oilseed species for biodiesel production; however, there is no much information about physiological evaluation of their seeds. The objective of this work was to adapt a controlled deterioration test methodology for niger seeds. Six niger seed lots were used, initially characterized for seed water content, germination percentage, germination first count, germination speed index, mean germination time, emergence percentage, emergence speed index, mean emergence time, initial stand, and seedlings length. In the controlled deterioration test, seed water content was adjusted to 16, 20 and 24% before they were treated to 41&deg;C for 24 and 48 h. After the deterioration period, seeds were subjected to the germination test and proceeded&nbsp;the evaluation at 7 d after sowing, counting the normal seedling percentage. It used the randomized design with four repetitions of 50 seeds. The controlled deterioration test was efficient to evaluate the niger seed physiological potential and it correlated positively with the seedling emergence test. It is recommended the combination of 16% of water content and 24 h of time exposure to evaluate the physiological potential of niger seeds

Accelerated aging test in niger seeds

Abstract:Niger is a promising oilseed species for biodiesel production but there is no much information about the physiological potential of its seeds. Thus, the aim was to adapt the methodologies of accelerated aging test on six lots of niger seeds. The test was carried out by traditional and with saturated salt solution (20 and 40 g NaCl.100 mL-1) methods at 41 and 45 °C for 24, 48, 72 and 96 hours. After the decay period, the seeds were submitted to the germination test, proceeding to an evaluation on the seventh day after sowing, counting the normal seedlings percentage. A completely randomized design with four replications of 50 seeds was used and the means were compared by Tukey's test. The accelerated aging test was correlated with seedling emergence and provided lots classification in at least two levels of vigor. For the accelerated aging test, the method with 20 g NaCl.100 mL-1 at 41 °C for 24 hours is recommend. The traditional method is not suitable because it provides water content variation between samples above what is tolerable