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Expression of estrus near timed artificial insemination (TAI) is associated with greater fertility, and estrus detection could improve TAI fertility or direct TAI management, although accurate estrus detection can be difficult and time-consuming using traditional methods. The aim of this study is to evaluate influence of estrus on pregnancy (artificial insemination pregnancy rates (P/AI)) and to validate an alternative method to classify estrus/heat expression using tail chalking (HEATSC) in postpartum Bos indicus cows subjected to TAI in progesterone–estrogen-based protocols. In experiment 1 (Exp. 1), cows (5491) were subjected to visual observation of estrus after progesterone device removal, before TAI, and P/AI was evaluated according to estrus and body condition score (BCS). Cows received a progesterone device and 2 mg estradiol benzoate (EB). After 8 days, the device was removed and 150 μg of d-cloprostenol and 300 IU equine chorionic gonadotrophin was given. Later, animals in Exp. 1 received 1 mg EB and TAI 44 to 48 h. In the Exp. 2 – 3830 cows using similar protocol, received different ovulation inducers: 1 mg EB (n=1624) or 1 mg estradiol cypionate (EC; n=2206) on day 8 (D8). Cows were then marked with chalk, and HEATSC evaluated at TAI on D10 (HEATSC1 – no chalk removal=no estrus expression; HEATSC2 – partial chalk removal=low estrus expression; HEATSC3 – near complete/complete chalk removal=high estrus expression). In Exp. 1, cows showing estrus presented greater P/AI (48.4% v. 40.2%, P<0.05). In Exp. 2, P/AI (HEATSC1 – 40.0%; HEATSC2 – 49.7%; HEATSC3 – 60.9%; P<0.001), and larger follicle timed artificial insemination (LFTAI) (<0.001) varied according to HEATSC. There was no difference in P/AI (P=0.41) or LFTAI (P=0.33) according to ovulation inducer. Cows with greater BCS showed greater P/AI in both experiments (P<0.05). Estrus presence and greater HEATSC improved P/AI, and EC v. EB used promoted differential estrus manifestation (cows showing HEATSC2 and HEATSC3: 79.5% with EB v. 69.98% with EC use, P<0.001), however, with similar P/AI. The use of HEATSC in B. indicus cows subjected to TAI is useful to identify cows with greater estrus expression and consequently improved pregnancy rates in TAI, allowing the cows with low HEATSC to be targeted for additional treatments aimed at improving P/AI.
The use of tail chalk and estrus/heat expression scores (HEATSC) evaluation is instrumental in identifying cows with greater estrus expression and greater artificial insemination pregnancy rates (P/AI) in cows submitted to timed artificial insemination (TAI), and cows with low or no estrus expression present lower P/AI. It was intended in this study to improve the pregnancy rates in TAI for Bos indicus beef cows, and gonadotrophin-releasing hormone (GnRH) injection was hypothesized to increase pregnancy rates in a TAI program for cows submitted to progesterone–estradiol-based protocols with low or no estrus expression, evaluated by HEATSC. Cows (n= 2284) received a progesterone device and 2 mg estradiol benzoate, after 8 days the device was removed and 1 mg estradiol cypionate, 150 μg of d-cloprostenol and 300 IU equine chorionic gonadotropin was administered. All cows were marked with chalk and HEATSC evaluated (scales 1 to 3) at TAI performed on day 10. Animals with HEATSC1 and HEATSC2 (n= 937) received 100 μg de gonadorelin (GNRH group; n= 470), or 1 ml saline (Control group; n= 467), and cows with HEATSC3 (named HEAT group; n= 1347) received no additional treatment. The larger dominant follicle, evaluated on day 8and at TAI (day 10), was greater in HEAT group (P= 0.0145 and P <0.001, respectively). Corpus luteum (CL) area and progesterone concentration was evaluated on day 17, and CL area was larger in HEAT group, intermediary in Control and lower in GnRH group (Control= 2.68 cm2, GnRH= 2.37 cm2, HEAT group= 3.07 cm2, P <0.001). Greater progesterone concentrations were found in HEAT group than in Control and GnRH groups (Control= 4.74 ng/ml, GnRH= 4.29 ng/ml, HEAT group= 6.08 ng/ml, P<0.001). There was a difference in ovulation rate, greater in HEAT group than GnRH and Control groups (Control= 72.5%; GnRH= 81.25%; HEAT group= 90.71%; P= 0.0024). Artificial insemination pregnancy rates was greater in HEAT group (57.09% (769/1347) than in Control and GNRH groups, with positive effect of GnRH injection at the time of TAI in P/AI (Control= 36.18% (169/467), GnRH= 45.95% (216/470); P<0.0001). In conclusion, GnRH application in cows with low HEATSC (1 and 2) is a simple strategy, requiring no changes in TAI management to increase pregnancy rates in postpartum beef cows submitted to progesterone–estradiol-based TAI protocols, without reaching, however, the pregnancy rates of cows that demonstrate high estrus expression at the TAI.
Ovarian biopsies from five health adult monkeys were collected by exploratory laparotomy. Preantral follicles (primordial, primary, and secondary) were classified as normal or degenerated and submitted to morphometric analysis in which granulosa cell counts and the areas of follicles, oocytes, and oocyte nuclei were measured. Ovarian fragments were also immunolabelled for the quantitative analysis of VEGFA and CD31 protein expression in the ovarian tissue and in the preantral follicles. In total, 213 preantral follicles was examined for morphometry and morphological classification. From this total, 20 (9.4%) were follicles enclosing two or more oocytes, i.e. multi-oocyte follicles (MOFs). From the 193 follicles enclosing only one oocyte, 46.3% were classified as primordial, 24,1% as transition, 23.3% as primary, and 6.3% as secondary follicles. The mean number of granulosa cells surrounding primordial, transition, primary, and secondary follicles was 9.2, 12.1, 18.7, and 45.3, respectively. Increase in oocyte diameter was observed from primary to secondary follicles, while the oocyte nucleus increased only when follicles reached the secondary stage. The expression of CD31 was strong in vessels, corpus luteum, and in normal oocytes and granulosa cells from preantral follicles at all developmental stages. Likewise, VEGFA expression was observed in vessels and preantral follicles (granulosa cells, the oocyte and the oocyte nucleus). We characterized the morphology, and morphometry and expression of angiogenic factors in normal and atretic preantral follicles from Sapajus apella. This description can support the analysis of follicular quality and survival after procedures such as transplantation and cryopreservation.
Background: Heterozygous loss-of-function mutations in the synaptic scaffolding gene SHANK2 are strongly associated with autism spectrum disorder (ASD). However, their impact on the function of human neurons is unknown. Derivation of induced pluripotent stem cells (iPSC) from affected individuals permits generation of live neurons to answer this question. Methods: We generated iPSCs by reprogramming dermal fibroblasts of neurotypic and ASD-affected donors. To isolate the effect of SHANK2, we used CRISPR/Cas9 to knock out SHANK2 in control iPSCs and correct a heterozygous nonsense mutation in ASD-affected donor iPSCs. We then derived cortical neurons from SOX1+ neural precursor cells differentiated from these iPSCs. Using a novel assay that overcomes line-to-line variability, we compared neuronal morphology, total synapse number, and electrophysiological properties between SHANK2 mutants and controls. Results: Relative to controls, SHANK2 mutant neurons have increased dendrite complexity, dendrite length, total synapse number (1.5-2-fold), and spontaneous excitatory postsynaptic current (sEPSC) frequency (3-7.6-fold). Conclusions: ASD-associated heterozygous loss-of-function mutations in SHANK2 increase synaptic connectivity among human neurons by increasing synapse number and sEPSC frequency. This is partially supported by increased dendrite length and complexity, providing evidence that SHANK2 functions as a suppressor of dendrite branching during neurodevelopment.
Acinetobacter spp. are important healthcare pathogens, being closely linked to antibiotic resistance and outbreaks worldwide. Although such species are rarely observed in patients with cystic fibrosis (CF), we describe the characteristics of 53 strains of Acinetobacter spp. isolated from the sputum of 39 Brazilian patients with CF. The species distribution was A. baumannii (n = 29), A. pittii (n = 13), A. nosocomialis (n = 8), A. seifertii (n = 1), A. soli (n = 1) and A. variabilis (n = 1) determined by partial rpoB gene sequencing. Sixteen strains (10 A. baumannii, 3 A. pittii and 3 A. nosocomialis) were multidrug-resistant (MDR) by disk diffusion test (30%) and eight MDR carbapenem-resistant A. baumannii strains harboured the blaOXA-23-like oxacillinase gene. Thirty-three sequence types (STs) were identified by multilocus sequence typing of which eight were novel (A. baumannii: 843, 844, 845, 847, 848; A. pitti: 643; A. nosocomialis: 862 and A. seifertii: 846); six STs (2 A. baumannii, 3 A. pittii and 1 A. nosocomialis) were found in more than one patient. Four strains of A. baumannii were assigned to two common clonal complexes (CCs), namely, CC1 (ST1, ST20 and ST160), and CC79 (ST79). This study underlines the extensive species diversity of Acinetobacter spp. strains in CF lung infections which may present difficulties for therapy due to significant antimicrobial resistance.
We present preliminary analysis of new HST observations of the transiting extrasolar planet HD 209458b. Photometric observations were obtained with the Fine Guidance Sensor (FGS) on the Hubble Space Telescope (HST), providing milli-mag precision and high time resolution (40 Hz). The FGS photometry allows us to derive precise stellar/orbital parameters (ephemeris, inclination, limb darkening) and planetary radius, and also allows a search for the presence of planetary rings and satellites. We discuss preliminary results and two approaches to modelling the observations.
An experiment was carried to evaluate the energy and protein requirements for the growth and maintenance of lambs of different sex classes. In all, 38 hair lambs (13.0±1.49 kg initial BW and 2 months old) were allocated in a factorial design with diet restriction levels (ad libitum, 30% and 60% feed restriction) and sex classes (castrated and non-castrated males). Four animals from each sex class were slaughtered at the beginning of the trial as a reference group to estimate the initial empty BW and body composition. The remaining lambs were weighed weekly to calculate BW gain (BWG), and when the animals fed ad libitum reached an average BW of 30 kg, all of the experimental animals were slaughtered. Before slaughter, fasted BW (FBW) was determined after 18 h without feed and water. Feed restriction induced reductions in body fat and energy concentration, whereas water restriction showed the opposite effect, and the protein concentration was not affected. The increase in BW promoted increases in body fat and energy content, and these increases were greater in castrated lambs, whereas the protein content was similar between classes tending to stabilize. The net energy required for gain (NEg) and the net protein required for gain (NPg) were not affected by sex class; therefore, an equation was generated for the combined results of both castrated and non-castrated lambs. The NEg varied from 1.13 to 2.01 MJ/day for lambs with BW of 15 and 30 kg and BWG of 200 g. The NPg varied from 24.57 to 16.33 g/day for lambs with BW of 15 and 30 kg and BWG of 200 g. The metabolizable energy efficiency for gain (kg) was 0.37, and the metabolizable protein efficiency for gain (kpg) was 0.28. The net energy required for maintenance (NEm) and the net requirement of protein for maintenance (NPm) did not differ between castrated and non-castrated lambs, with values of 0.241 MJ/kg FBW0.75 per day and 1.30 g/kg FBW0.75 per day, respectively. The metabolizable energy efficiency for maintenance (km) was 0.60, and the efficiency of metabolizable protein use for maintenance (kpm) was 0.57. Nutritional requirements for growth and maintenance did not differ between castrated and non-castrated lambs. This study emphasizes the importance of updating the tables of international committees and of including data obtained from studies with sheep breeds raised in tropical conditions, with the purpose of improving the productive efficiency of the animals
Achromobacter spp. are opportunistic pathogens increasingly recovered from adult patients with cystic fibrosis (CF). We report the characterization of 122 Achromobacter spp. isolates recovered from 39 CF patients by multilocus sequence typing, virulence traits, and susceptibility to antimicrobials. Two species, A. xylosoxidans (77%) and A. ruhlandii (23%) were identified. All isolates showed a similar biofilm formation ability, and a positive swimming phenotype. By contrast, 4·3% and 44·4% of A. xylosoxidans and A. ruhlandii, respectively, exhibited a negative swarming phenotype, making the swimming and swarming abilities of A. xylosoxidans significantly higher than those of A. ruhlandii. A. xylosoxidans isolates from an outbreak clone also exhibited significantly higher motility. Both species were generally susceptible to ceftazidime, ciprofloxacin, imipenem and trimethoprim/sulphamethoxazole and there was no significant difference in susceptibility between isolates from chronic or sporadic infection. However, A. xylosoxidans isolates from chronic and sporadic cases were significantly more resistant to imipenem and ceftazidime than isolates of the outbreak clone.
We examined functional outcomes and quality of life of whole brain radiotherapy (WBRT) with integrated fractionated stereotactic radiotherapy boost (FSRT) for brain metastases treatment. Methods Eighty seven people with 1-3 brain metastases were enrolled on this Phase II trial of WBRT (30Gy/10)+simultaneous FSRT, (60Gy/10). Results Mean (Min-Max) baseline KPS, Mini Mental Status Exam (MMSE) and FACT-BR quality of life were 83 (70-100), 28 (21-30) and 143 (98-153). Lower baseline MMSE (but not KPS or FACT-Br) was associated with worse survival after adjusting for age, number of metastases, primary and extra-cranial disease status. Crude rates of deterioration (>10 points decrease from baseline for KPS and FACT-Br, MMSE fall to<27) ranged from 26-38% for KPS, 32-59% for FACT-Br and 0-16%for MMSE depending on the time-point assessed with higher rates generally noted at earlier time points (<6months post-treatment). Using a linear mixed models analysis, significant declines from baseline were noted for KPS and FACT-Br (largest effects at 6 weeks to 3 months) with no significant change in MMSE. Conclusions The effects on function and quality of life of this integrated treatment of WBRT+simultaneous FSRT were similar to other published series combining WBRT+SRS.
The Brazilian Amazon rain forest has lost c. 17% of its originally forested portion, due to deforestation and selective logging. Forest degradation caused by logging contributes to loss of animal species that require specialized habitats to survive, such as woodcreepers that inhabit understorey areas. Habitat associations of woodcreeper species can be important for identifying species that have restricted distribution and/or habitat specialization. Our study investigates the effects of spatial variation in forest structure and some landscape features (canopy openness, altitude, distance to stream and exploited basal area) on the abundance and composition of woodcreeper assemblage in selectively logged tropical forests in Southern Amazonia. We used mist-nets and points count to quantify the composition and abundance of woodcreepers in 32 plots in three sites. Plots were spatially arranged in PPBio LTER sites (long-term ecological research plots, systematically spaced at 1-km intervals) in Southern Amazonia. A total of 240 individuals (captured, observed and/or heard) belonging to 11 woodcreeper species were detected. Mantel tests showed that there is no spatial autocorrelation among woodcreeper assemblage and distance between plots. Altitude and canopy openness were significantly associated with the composition of the woodcreeper assemblage. Altitude was negatively associated with species richness, and the abundance of the two dominant species (Glyphorynchus spirurus and Xiphorhynchus elegans). The negative relationship with canopy openness suggests that woodcreeper assemblages that inhabit understorey are likely to be indirectly affected by selective logging which reduces canopy cover. The selective logging indirectly changes bird species assemblages, and depending on the intensity, may result in the local extinction of some insectivorous species. Short- and long-term studies addressing different intensities of selective logging are needed to determine the impacts on the bird species and forest structure.
This experiment compared growth, physiological, and reproductive responses of beef heifers with (MI) or without (CON) access to a creep-feeder, as a manner to stimulate metabolic imprinting while nursing their dams. On day 0, 60 Angus×Hereford heifers were ranked by BW and age (140±3 kg and 68±3 days), and assigned to pairs so all ranking criteria were similar between heifers within each pair. On day 1, pairs were randomly assigned to MI (n=15) or CON (n=15). From day 1 to 51, MI pairs and their dams were allocated to 15 drylot pens where heifers had ad libitum access to a corn-based supplement through a creep-feeder. The CON pairs and their dams were maintained in an adjacent single drylot pen. From day 52 to 111, treatments were managed as a single group on a semiarid range pasture. On day 111, heifers were weaned and allocated to two pastures (one pasture/treatment), receiving hay and a corn-based concentrate until day 326. Heifer BW was recorded before and at the end of the creep-feeding period (day 1 to 51), and on days 112 and 326. On days 0, 51, 111, 187, 261, and 325, jugular blood was collected and real-time ultrasonography for longissimus muscle depth and backfat thickness assessment was performed. Blood was also collected every 10 days from days 113 to 323 for puberty evaluation via plasma progesterone. Liver and subcutaneous fat biopsies were performed on days 51, 111, 261 and 325. Average daily gain was greater (P<0.01) for MI than CON from day 1 to 51, tended (P=0.09) to be greater for CON than MI from day 112 to 326, while BW on day 326 was similar between treatments. On day 51, MI had greater (P⩽0.01) plasma IGF-I and glucose concentrations, as well as mRNA expression of hepatic pyruvate carboxylase and adipose fatty acid synthase than CON. On days 261 and 325, plasma insulin concentrations were greater (P⩽0.03) in CON than MI. Mean mRNA expression of hepatic IGF-I and adipose peroxisome proliferator-activated receptor gamma were greater (P⩽0.05) in MI than CON. No treatment effects were detected for puberty attainment rate. In conclusion, supplementing nursing heifers via creep-feeding for 50 days altered physiological and biochemical variables suggestive of a metabolic imprinting effect, but did not hasten their puberty attainment.
We performed an observational study of the relation between the interstellar magnetic field alignment and star formation in twenty (20) sky regions containing Bok Globules. The presence of young stellar objects in the globules is verified by a search of infrared sources with spectral energy distribution compatible with a pre main-sequence star. The interstellar magnetic field direction is mapped using optical polarimetry. These maps are used to estimate the dispersion of the interstellar magnetic field direction in each region from a Gaussian fit, σB. In addition to the Gaussian dispersion, we propose a new parameter, η, to measure the magnetic field alignment that does not rely on any function fitting. Statistical tests show that the dispersion of the magnetic field direction is different in star forming globules relative to quiescent globules. Specifically, the less organised magnetic fields occur in regions having young stellar objects.
Leishmaniasis is a set of clinically distinct infectious diseases caused by Leishmania, a genus of flagellated protozoan parasites, that affects ∼12 million people worldwide, with ∼2 million new infections annually. Plants are known to produce substances to defend themselves against pathogens and predators. In the genus Lycopersicon, which includes the tomato, L. esculentum, the main antimicrobial compound is the steroidal glycoalkaloid α-tomatine. The loss of the saccharide side-chain of tomatine yields the aglycone tomatidine. In the present study, we investigated the effects of tomatidine on the growth, mitochondrial membrane potential, sterol metabolism, and ultrastructure of Leishmania amazonensis promastigotes. Tomatidine (0·1 to 5 μM) inhibited parasite growth in a dose-dependent manner (IC50=124±59 nM). Transmission electron microscopy revealed lesions in the mitochondrial ultrastructure and the presence of large vacuoles and lipid storage bodies in the cytoplasm. These structural changes in the mitochondria were accompanied by an effective loss of mitochondrial membrane potential and a decrease in ATP levels. An analysis of the neutral lipid content revealed a large depletion of endogenous 24-alkylated sterols such as 24-methylene-cholesta-5, 7-dien-3β-ol (5-dehydroepisterol), with a concomitant accumulation of cholesta-8, 24-dien-3β-ol (zymosterol), which implied a perturbation in the cellular lipid content. These results are consistent with an inhibition of 24-sterol methyltransferase, an important enzyme responsible for the methylation of sterols at the 24 position, which is an essential step in the production of ergosterol and other 24-methyl sterols.
To access the fermentative response of equine caecal microbial population to nitrogen availability, an in vitro study was conducted using caecal contents provided with adequate energy sources and nitrogen as limiting nutrient. Two nitrogen (N) sources were provided, protein (casein) and non-protein (urea). Caecal fluid, taken from three cannulated horses receiving a hay–concentrate diet, was mixed with a N-free buffer–mineral solution. The influence of four N levels (3.7, 6.3, 12.5 or 25 mg of N in casein or urea) was studied using the gas production technique. Total volatile fatty acids (VFA), NH3-N and gas production were measured after a 24-h incubation period. Microbial biomass was estimated using adenine and guanine bases as internal markers, and ATP production was estimated stoichiometrically. Microbial growth efficiency (YATP) and gas efficiency (Egas) were estimated. Fermentation with casein as the sole N source was generally characterized by lower total VFA, NH3-N, total gas production and higher acetate : propionate (A : P) ratio and YATP than with urea. Results herein presented indicate that, under these in vitro conditions, caecal microbial population does in fact use urea N, but less efficiently than casein in terms of microbial growth.
This paper presents a linked hydro-economic model and uses it to examine the regional effects of water use regulations and product price changes on the agriculture of the São Francisco River Basin, Brazil. The effects of weather on surface water availability are explicitly addressed using the hydrological model MIKE-Basin. Farmers’ adjustments to changes in precipitation, surface water availability, and other factors are quantified using an economic model based on non-linear programming techniques. The models are externally linked. Results show that regional impacts, at the sub-basin level, vary depending on the location of each sub-basin relative to river flows. The effects of water use regulations and of exogenous price shocks on agriculture depend on weather, location, product mix and production technology. Implications of these results for policies designed to manage agriculture and water use are discussed.
An experiment was conducted to assess the potential of long-chain alcohols (LCOH), in alternative or combined with alkanes and long-chain fatty acids (LCFA), as faecal markers to estimate the diet composition of goats grazing heathland vegetation with associated improved pastures. A total of seven diets were offered across the grazing season. The diets were composed of mixtures of herb species (Lolium perenne and Trifolium repens) and woody species (Erica spp., Calluna vulgaris and Ulex gallii) in an attempt to simulate diet selection of goats on these complex vegetation areas. The diet composition was estimated using LCOH markers alone or combined with alkanes, LCFA and alkanes+LCFA, by least square optimization procedures. The data showed large differences between plant species in their LCOH profile. Generally, plant species showed higher LCOH concentrations than those of alkanes and lower than LCFA markers. Faecal recovery of LCOH was incomplete and increased in a linear manner (P < 0.001) with the carbon-chain length, and was influenced by diet composition and its digestibility. The diet composition estimates based on LCOH alone were more accurate (P < 0.05) than those using alkanes or LCFA alone. Results showed that the combination of LCOH with alkanes, LCFA and alkanes+LCFA resulted in more accurate (P < 0.05) estimates of diet composition, indicating that LCOH provided different discriminatory information to that of alkanes and LCFA, helping in the discrimination of the plant species used in this experiment. Results indicate that correction of faecal LCOH concentrations to incomplete faecal recovery is necessary to obtain more accurate estimates of diet composition. Nevertheless, it seemed that the use of a less accurate recovery correction on LCOH markers had a lower impact on the accuracy of estimates than that of alkanes and LCFA.
Pine wilt disease, caused by the pinewood nematode Bursaphelenchus xylophilus (Steiner and Buhrer) Nickle, is originating severe infections in pine trees. The disease is detected when external symptoms appear (e.g. needle chlorosis), but trees could remain asymptomatic for long periods and serve as a long-term host. The primary goal of this study was to assess the effect of inoculation with an avirulent isolate of B. xylophilus (C14-5) on different Pinus spp. seedlings (P. sylvestris, P. nigra, P. pinea and P. pinaster). At the same time, seedlings were also inoculated with a virulent strain, HF, in order to compare the phenotypic and genomic results of the two types of inoculations. The effect of inoculation was determined in terms of expression of various Pinus genes potentially involved in the response to the disease.The results suggest that P. pinea and P. nigra are more resistant to infection by the nematode than P. sylvestris and P. pinaster. The phenotypic and genetic differences were more marked among P. pinea and P. pinaster.
In this work, we report optical and structural properties of vertical aligned self-assembled InAs quantum dots multilayers. The InAs quantum dots samples were grown by Molecular Beam Epitaxy. Employing Atomic Force Microscopy, Transmission Electron Microscopy, and Gracing Incident X-ray Diffraction we have studied the structural properties of samples with different number of periods of the multiplayer structure, as well as different InAs coverage. The optical properties were studied using Photoluminescence spectroscopy.