Estimating the mass of asteroid 253 mathilde from tracking data during the NEAR flyby

The terminal navigation of the Near Earth Asteroid Rendezvous (NEAR) spacecraft during its close flyby of asteroid 253 Mathilde involved coordinated efforts to determine the heliocentric orbits of the spacecraft and Mathilde and then to determine the relative trajectory of the spacecraft with respect to Mathilde. The gravitational perturbation of Mathilde on the passing spacecraft was apparent in the spacecraft tracking data. As a result of the accurate targeting achieved, these data could be used to determine Mathilde's mass as 1.033 (+/- 0.044) x 10(20) grams. Coupled with a volume estimate provided by the NEAR imaging team, this mass suggests a low bulk density for Mathilde of 1.3 grams per cubic centimeter.     

Development of a quantitative real‐time PCR assay for the detection of Phytophthora austrocedrae,an emerging pathogen in Britain

A TaqMan real‐time PCR assay was developed for Phytophthora austrocedrae, an emerging pathogen causing severe damage to juniper in Britain. The primers amplified DNA of the target pathogen down to 1 pg of extracted DNA, in both the presence and absence of host DNA, but did not amplify any of the non‐target Phytophthora and fungal species tested. The assay provides a useful tool for screening juniper populations for the disease.     

Synthesis and antifungal activity of novel sclerotiorin analogues

Sclerotiorin 1, first isolated from Penicillium sclerotiorum, has weak antifungal activity and belongs to the azaphilone-type family of natural products. Several series of sclerotiorin analogues were designed and synthesized with the aim of discovering novel fungicides with improved activity. The syntheses involved two key steps, cycloisomerization and then oxidation, and used a simple and efficient Sonogashira cross-coupling reaction to construct the required functionalized precursor. With sclerotiorin as a control, the activities of the newly synthesized analogues were evaluated against seven fungal pathogens, and several promising candidates (compounds 3a?, 3d?, 3e?, 3f? and 3k?) with greater activity and simpler structures than sclerotiorin were discovered. In addition, preliminary structure-activity relationships were studied, which revealed that not only the chlorine or bromine substituent at the 5-position of the nucleus but also the phenyl group at the 3-position and the substituent pattern on it contributed crucially to the observed antifungal activity. Analogues with a methyl substituent at the 1-position have reduced levels of activity, while those with a free hydroxyl group in place of acetoxy at the quaternary center of the bicyclic ring system retain activity.     

Testosterone serum profile,semen characteristics and testicular biometry of Mangalarga Marchador stallions in a tropical environment

This study was conducted to characterize the daily profile of testosterone secretion and its mean concentrations in the four seasons as well as to evaluate the semen characteristics and testicular biometry of Mangalarga Marchador stallions throughout the year in a tropical region. Three stallions were submitted to semen collections and evaluation of testicular biometry every 14 days along a year. Blood samples were collected once at the middle of each season, in a 20‐min interval during 24 hr in order to evaluate the testosterone secretion profiles among seasons. Testosterone concentrations along the day were higher at the beginning of the afternoon (from 12:00 to 15:00 hr), but a circadian secretion was not clearly observed. Mean testosterone concentrations did not differ among seasons (p > .05), but a pattern of secretion along the day showed variations with higher concentrations in the afternoon during the winter. Ejaculate volume was higher during summer; however, sperm motility decreased in summer and spring. Total sperm in ejaculate, sperm morphology and testicular biometry kept constant along the year showing no differences among the seasons. The results demonstrated that in a tropical region, reproductive aspects of stallions did not show a clearly defined seasonal variation, and months of autumn and winter were not unsuitable for reproduction of the males.     

Immotile Short‐Tail Sperm Defect in Nelore (Bos taurus indicus) Breed Bulls

This case study reported the presence of short tail sperm defect in the semen of three Nelore breed bulls. The sperm presented 0% of motility in the three animals evaluated and a total of 70%, 61% and 34% of pathologies of the intermediate piece of the tail respectively for animals 1, 2 and 3. It was identified that animals 2 and 3 had high degree of inbreeding, although no relationship was found with animal 1. Animal 2 was the only one that presented inbreeding coefficient (6.25%). His half‐sib (animal 3) and animal 1, from the same herd, had shown no inbreeding, showing that inheritance is not the only determinant factor for its incidence on Nelore males.     

Protease-activated receptors in dorsal motor nucleus of vagus in rats with inflammatory bowel disease

AIM: To demonstrate the presence of protease-activated receptor-1 (PAR-1) and PAR-2 in the dorsal motor nucleus of the vagus (DMNV), and to elucidate the cellular mechanisms that are triggered upon receptor activation in the rat with inflammatory bowel disease. METHODS: Twenty rats were used to produce the animal model of inflammatory bowel disease. The tissues of DMNV were collected from these animals for measuring PAR-1 and PAR-2. By using the Fura-2-AM, the concentration of intracellular calcium in primary cultured DMNV cells from newborn rats was observed in the presence of PAR-1 or PAR-2. RESULTS: Thrombin and PAR-1 agonist peptide (PARP-1) activated PAR-1 with a maximum change in intracellular calcium concentration Δ［Ca2+］i. Trypsin and PAR-2 agonist peptide (PARP-2) activated PAR-2 with a maximum Δ［Ca2+］i. Inhibition of phospholipase C (PLC) by 1 μmol/L U73312 decreased Δ［Ca2+］i induced by PAR-1 activation. The PAR-2-mediated Δ［Ca2+］i decreased when PLC was inhibited. Blockade of IP3 receptor by 2APB decreased the Δ［Ca2+］i due to PAR-1 and PAR-2 activation. CONCLUSION: Our results indicate that PAR-1 and PAR-2 are present in the DMNV neurons, and their activation leads to increases in intracellular calcium via signal transduction mechanism that involves activation of phospholipase C and the production of inositol 1,4,5-trisphosphate.     

Effects of α-MSH on the Ca2+ channels of primary DMNV cells and effects of anti-apoptosis on primary DMNV cells after activation of melanocortin receptors

AIM: α-MSH is elevated in patients with inflammatory bowel disease and has been implicated as an inflammatory mediator. The purpose of this study was to investigate effects of α-MSH on the Ca2+ channels of primary DMNV cells, the effects of gastrointestinal inflammation on the dorsal motor nucleus of the vagus in rats, as well as the effects of proinflammatory cytokines and α-MSH on neurons from the dorsal motor nucleus of the vagus in vitro. METHODS: In vitro studies the primary culture of neurons from the dorsal motor nucleus of the vagus was performed. Single-cell cytoplasmic calcium transients were determined using the fluorescence dye fura-2-AM. Cell proliferation and apoptosis were measured by enzyme-linked immunosorbent assay. RESULTS: MC4R mRNA was expressed in the DMNV cells of normal rats. Activation of MC4R promoted the calcium influx of primary DMNV cells. The addition of α-MSH to thrombin or trypsin resulted in significant decreases in apoptosis compared to thrombin or trypsin alone. CONCLUSION: Functionally active α-MSH receptors are linked to Ca2+ channels in DMNV neurons. In cultured DMNV cells, α-MSH attenuates neuronal apoptosis and reverses inhibition of cellular proliferation.