A novel QTL <Emphasis Type="Italic">qSPP2.2</Emphasis> controlling spikelet per panicle identified from <Emphasis Type="Italic">Oryza longistaminata</Emphasis> (A. Chev. et Roehr.), mapped and transferred to <Emphasis Type="Italic">Oryza sativa</Emphasis> (L.)

Increasing the rice productivity from the current 10 to 12 tons/ha to meet the demand of estimated 8.8 billion people in 2035 is posing a major challenge. Wild relatives of rice contain some novel genes which can help in improving rice yield. Spikelet per panicle (SPP) is a valuable trait for determining yield potential in rice. In this study, a major QTL for increasing SPP has been identified, mapped, and transferred from African wild rice O. longistaminata to O. sativa (L.). The QTL was mapped on the long arm of chromosome 2 in a 167.1 kb region flanked by SSR markers RM13743 and RM13750, which are 1.0 cM apart, and is designated as qSPP2.2. The QTL explained up to 30% of phenotypic variance in different generations/seasons and showed positive additive effect of allele contributed by O. longistaminata. In addition, O. longistaminata allele in qSPP2.2 contributed to increase in grains per panicle, but decrease in the tillers per plant. The 167.1 kb region contains 23 predicted genes. Based on the functional annotation, three genes, LOC_Os02g44860, LOC_Os02g44990, and LOC_Os02g45010, were selected as putative candidates for characterization. Sequence analysis of the three genes revealed functional variations between the parental lines for LOC_Os02g44990 and a variation in 5′UTR for LOC_Os02g45010 which will help further to identify putative candidate gene(s). This is the first yield component QTL to be identified, mapped, and transferred from O. longistaminata.     

Escherichia coli exhibiting gram positivity after cetyl pyridinium chloride treatment

Summary Treatment with a solution of the detergent cetyl pyridinium chloride develops gram positivity in E. coli as is evident from the increased retention of crystal violet by the bacteria. Since cetyl pyridinium chloride has been found to remove larger quantity of lipid from E. coli than from the normal gram positive bacteria S. aureus, it is reasonable to think that lipid content in a bacteria may have an important role in determining the gram character of it. Gram negative bacteria generally contain more lipid than the gram positive ones.     

Differential Behavioral and Endocrinological Effects of Corticotropin-Releasing Hormone (CRH) in the Syracuse High- and Low-Avoidance Rats

The Syracuse high- and low-avoidance rats, which have been selectively bred for good (SHA/Bru) or poor (SLA/Bru) avoidance learning in a two-way shuttle box, differ in emotionality. This experiment investigated the effect of corticotropin-releasing hormone (CRH), administered centrally (0, 0.1, 0.5, and 1.0 μg), on conditioned suppression and on the hypothalamic–pituitary–adrenocortical system. Three groups of animals were used: SHA/Bru rats conditioned at 0.21 or 0.43 mA and SLA/Bru rats conditioned at 0.21 mA. The results confirm those of previous studies which found that SLA/Bru rats show greater conditioned suppression than the SHA/Bru rats at the low shock intensity and that at 0.43 mA, the SHA/Bru animals acquire a level of conditioning comparable to that of the SLA/Bru animals at 0.21 mA. The results show that the nonlinear behavioral effect of CRH is independent of strain and produces comparable effects in animals of both strains, but only when level of conditioning is equated. Adrenal and plasma concentrations of corticosterone increased in all three groups of animals as a direct linear function of dose of CRH. Both greater levels of conditioning and larger amounts of CRH increase the synthesis of corticosterone more in SHA/Bru animals than in the SLA/Bru animals. Thus, genetic variation, which differentiates the behavioral and endocrinological characteristics of these animals, shows that these effects of CRH can be independent of each other and suggests that some minimal level of conditioned fear is necessary for CRH to exert its anxiogenic effect.     

Quantification of Frankia in soils using SYBR Green based qPCR

A SYBR Green based qPCR method was developed for the quantification of clusters 1 and 3 of the actinomycete Frankia in soils. Primer nifHr158 was designed to be used as reverse primer in combination with forward primer nifHf1 specifically amplifying a 191-bp fragment of the nifH gene of these Frankia. The primer combination was tested for specificity on selected pure cultures, and by comparative sequence analyses of randomly selected clones of a clone library generated with these primers from soil DNA extracts. After adjustments of DNA extraction conditions, and the determination of extraction efficiencies used for sample normalization, copy numbers of nifH genes representing Frankia of clusters 1 and 3 were quantified in different mineral soils, resulting in cell density estimates for these Frankia of up to 10(6) cells [g soil {dry weight}](-1) depending on the soil. Despite indications that the nifH gene is not a perfect target for the quantification of Frankia, the qPCR method described here provides a new tool for the quantification and thus a more complete examination of the ecology of Frankia in soils.     

Using PCR-based detection and genotyping to trace Streptococcus salivarius meningitis outbreak strain to oral flora of radiology physician assistant

We recently investigated three cases of bacterial meningitis that were reported from a midwestern radiology clinic where facemasks were not worn during spinal injection of contrast agent during myelography procedures. Using pulsed field gel electrophoresis we linked a case strain of S. salivarius to an oral specimen of a radiology physician assistant (RPA). We also used a real-time PCR assay to detect S. salivarius DNA within a culture-negative cerebrospinal fluid (CSF) specimen. Here we extend this investigation through using a nested PCR/sequencing strategy to link the culture-negative CSF specimen to the case strain. We also provide validation of the real-time PCR assay used, demonstrating that it is not solely specific for Streptococcus salivarius, but is also highly sensitive for detection of the closely related oral species Streptococcus vestibularis. Through using multilocus sequence typing and 16S rDNA sequencing we further strengthen the link between the CSF case isolate and the RPA carriage isolate. We also demonstrate that the newly characterized strains from this study are distinct from previously characterized S. salivarius strains associated with carriage and meningitis.