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The melt analysis feature in most real-time polymerase chain reaction (PCR) instruments is a simple method for determining if expected or unexpected products are present. High-resolution melt (HRM) analysis seeks to improve the precision of melt temperature measurements for better PCR product sequence characterization. In the area of tuberculosis (TB) drug susceptibility screening, sequencing has shown that a single base change can be sufficient to make a first-line TB drug ineffective. In this study, a reagent-based calibration strategy based on synthetic left-handed (L)-DNA, designated LHRM, was developed to confirm validation of a PCR product with single base resolution. To test this approach, a constant amount of a double-stranded L-DNA melt comparator was added to each sample and used as a within-sample melt standard. The performance of LHRM and standard HRM was used to classify PCR products as drug-susceptible or not drug-susceptible with a test bed of nine synthetic katG variants, each containing single or multiple base mutations that are known to confer resistance to the first-line TB drug isoniazid (INH). LHRM achieved comparable classification to standard HRM relying only on within-sample melt differences between L-DNA and the unknown PCR product. Using a state-of-the-art calibrated instrument and multiple sample classification analysis, standard HRM was performed at 66.7% sensitivity and 98.8% specificity. Single sample analysis incorporating L-DNA for reagent-based calibration into every sample maintained high performance at 77.8% sensitivity and 98.7% specificity. LHRM shows promise as a high-resolution single sample method for validating PCR products in applications where the expected sequence is known.
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DNA , Mycobacterium tuberculosis , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/efeitos dos fármacos , DNA/análise , DNA/genética , Reação em Cadeia da Polimerase/métodos , Temperatura de Transição , Antituberculosos/farmacologia , Reação em Cadeia da Polimerase em Tempo Real/métodosRESUMO
A numerical method is proposed to simulate the roughness scale interface dynamics of a slow-moving fluid interface as it advances over a chemically homogeneous rough surface. Analysis of the governing augmented Navier-Stokes and Young's boundary condition equations shows how the local interface behavior can be represented via a series of incrementally advanced equilibrium interfacial morphologies. Combined with a roughness scale mechanical energy balance [Harvie, D. J. E. Contact-angle hysteresis on rough surfaces: mechanical energy balance framework. J. Fluid Mech. 2024, 986, A17], the simulations are used to calculate the energy dissipation associated with a surface decorated with a periodic array of round-edge square pillars. This dissipation is used to predict static contact angle hysteresis (CAH) from knowledge of just the surface roughness topography and equilibrium contact angle. We show that the energy dissipated varies approximately as Ïlnâ¯Ï (with Ï being the area fraction), becoming zero as Ï â 0. The CAH predicted by our method is in good agreement with the experimental results of Forsberg et al. [Forsberg, P. S.; Priest, C.; Brinkmann, M.; Sedev, R.; Ralston, J. Contact line pinning on microstructured surfaces for liquids in the Wenzel state. Langmuir 2010, 26, 860-865], thereby demonstrating that our numerical method of simulating interfacial dynamics adequately captures the real interface motion, as well as illustrating how far-field contact angle and energy dissipation approaches are consistent for this surface. We also compute CAH for an interface moving at 45° to the surface periodicity direction to show that the experimental measurements are bracketed by the 0° and 45° advance direction results. The proposed method opens up the field to quantitative analysis, surface functionalization, and design for different specific applications.
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Recent theoretical work and experiments at molecular junctions have provided a strong conceptualization for the effects of oriented electric fields (OEFs) on organic reactions. Depending on the axis of application, OEFs can increase (or decrease) the reaction rate or distinguish between isomeric pathways. Despite the conceptual elegance of OEFs, which may be applied externally or induced locally, as tools for catalyzing organic reactions, implementation in synthetically relevant systems has been hampered by inefficiencies in evaluating reaction sensitivity to field effects. Herein, we describe the development of the Automated Variable Electric-Field DFT Application (A.V.E.D.A.) for streamlined evaluation of a reaction's susceptibility to OEFs. This open-source software was designed to be accessible for nonexpert users of computational and programming tools. Following initiation by a single command (and with no subsequent intervention) the Linux workflow manages a series of density functional theory calculations and mathematical manipulations to optimize local-minimum and transition-state structures in oriented electric fields of increasing magnitude. The resulting molecular and reaction dipole moments, field-perturbed geometries, and net effective activation energies are compiled for user interpretation. Ten representative pericyclic reactions that showcase the development and evaluation of A.V.E.D.A. are described.
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The objective was to investigate the influence of cattle origin and region of finishing on the prevalence of Salmonella, Escherichia coli O157:H7, and select antimicrobial resistance in E. coli populations. Yearling heifers (n = 190) were utilized in a 2 × 2 factorial arrangement. After determining fecal Salmonella prevalence, heifers were sorted into one of four treatments: heifers originating from South Dakota (SD) and finished in SD (SD-SD); heifers originating from SD and finished in Texas (SD-TX); heifers originating from TX and finished in SD (TX-SD); and heifers originating from TX and finished in TX (TX-TX). Fecal, pen, and water scum line samples were collected longitudinally throughout the study; hide swab and subiliac lymph node (SLN) samples were collected at study end. A treatment × time interaction was observed (p ≤ 0.01) for fecal Salmonella prevalence, with prevalence being greatest for TX-TX and TX-SD heifers before transport. From day (d) 14 through study end, prevalence was greatest for TX-TX and SD-TX heifers compared with SD-SD and TX-SD heifers. Salmonella prevalence on hides were greater (p ≤ 0.01) for heifers finished in TX compared with SD. Salmonella prevalence in SLN tended (p = 0.06) to be greater in TX-TX and SD-TX heifers compared with TX-SD and SD-SD. Fecal E. coli O157:H7 prevalence had a treatment × time interaction (p = 0.04), with SD-TX prevalence being greater than TX-SD on d 56 and SD-SD and TX-TX being intermediate. A treatment × time interaction was observed for fecal trimethoprim-sulfamethoxazole-resistant and cefotaxime-resistant E. coli O157:H7 prevalence (p ≤ 0.01). Overall, these data suggest that the region of finishing influences pathogenic bacterial shedding patterns, with the initial 14 d after feedlot arrival being critical for pathogen carriage.
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Anti-Infecciosos , Doenças dos Bovinos , Infecções por Escherichia coli , Escherichia coli O157 , Animais , Bovinos , Feminino , Prevalência , Incidência , Fezes/microbiologia , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/veterinária , Texas , Salmonella , Doenças dos Bovinos/tratamento farmacológico , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/microbiologia , Contagem de Colônia MicrobianaRESUMO
HIV develops single nucleotide polymorphisms (SNPs), some of which lead to drug resistance mutations (DRMs) that prevent therapeutic viral suppression. Genomic sequencing enables healthcare professionals to select effective combination antiretroviral therapy (ART) to achieve and maintain viral suppression. However, sequencing technologies, which are resource-intensive, are limited in their availability. This report describes the first step toward a highly specific ligation-based SNP discrimination method with endpoint PCR detection, which is more suitable for resource-limited clinics. The approach is based on magnetic bead processing to maximize reaction product transfer and minimize the carryover of incompatible buffer for three consecutive enzymatic reactionsâreverse transcription (RT), oligonucleotide ligation assay (OLA), and PCR. The method improved PCR detection following RT â OLA by 8.06 cycles (â¼250-fold) compared to direct pipette processing and detected between 103 and 104 RNA copies per reaction. In studies with synthesized nucleic acids based on the well-studied HIV mutation, K103N, the assay successfully differentiated between wild-type and mutant for RNA targets with high specificity. With further development, this design provides a pathway for SNP detection with more accessible PCR instrumentation and is a step toward a self-contained processing approach that incorporates the SNP specificity of the ligation reaction for more effective clinical management of DRMs in resource-constrained settings.
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Fármacos Anti-HIV , Farmacorresistência Viral , Infecções por HIV , HIV-1 , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico , Farmacorresistência Viral/genética , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , HIV-1/genética , Humanos , Fenômenos Magnéticos , MutaçãoRESUMO
Many baseball pitching studies have used inverse dynamics to assess throwing arm kinetics as high and repetitive kinetics are thought to be linked to pitching injuries. However, prior studies have not used participant-specific body segment inertial parameters (BSIPs), which are thought to improve analysis of high-acceleration motions and overweight participants. This study's objectives were to (1) calculate participant-specific BSIPs using dual energy X-ray absorptiometry (DXA) measures, (2) compare inverse dynamic calculations of kinetics determined by DXA-calculated BSIPs (full DXA-driven inverse dynamics) against kinetics using the standard inverse dynamics approach with scaled BSIPs (scaled inverse dynamics), and (3) examine associations between full DXA-driven kinetics and overweight indices: body mass index (BMI) and segment mass index (SMI). Eighteen participants (10-11 years old) threw 10 fastballs that were recorded for motion analysis. DXA scans were used to calculate participant-specific BSIPs (mass, center of mass, radii of gyration) for each pitching arm segment (upper arm, forearm, hand), BMI, and SMI. The hypotheses were addressed with t-tests and linear regression analyses. The major results were that (1) DXA-calculated BSIPs differed from scaled BSIPs for each pitching arm segment; (2) calculations for shoulder, but not elbow, kinetics differed between the full DXA-driven and scaled inverse dynamics analyses; and (3) full DXA-driven inverse dynamics calculations for shoulder kinetics were more often associated with SMI than BMI. Results suggest that using participant-specific BSIPs and pitching arm, SMIs may improve evidence-based injury prevention guidelines for youth pitchers.
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Beisebol , Lesões no Cotovelo , Articulação do Ombro , Adolescente , Braço , Beisebol/lesões , Fenômenos Biomecânicos , Composição Corporal , Criança , Humanos , Cinética , SobrepesoRESUMO
The aim of this study was to document California, Idaho, South Dakota, and Washington dairy producers' perspectives on the health and business implications of COVID-19 during the pandemic second wave. Dairy producers were reached by a 14-question anonymous mail survey during June and July of 2020. We obtained 226 responses (response rate: 9.3% CA, 8.6% ID, 31.4%, and 10.0% WA). Responses were grouped by state (CA: 48.7%, ID: 15.9%, SD: 21.7%, or WA: 13.7%) and dairy size [based on number of cows; small (<100): 14.1%, medium (100-499): 27.7%, medium-large (500-1,999): 33.2%, or large (≥2,000): 25.0%]. Survey responses were summarized, and multiple correspondence analysis was used to map responses and identify data clusters. At the time of the survey, some respondents suspected (3%) or had confirmed (9%) COVID-19 cases on their premises. Respondents were somewhat or very concerned about the health (75%) and business (92%) implications associated with COVID-19. Producers were concerned about the health of their families, employees, and employees' families; having to reduce production; workforce shortage; limited goods availability; and lack of services. Producers perceived that their employees were somewhat or very concerned (74%) with the pandemic. There was COVID-19 safety information or training provided (78%) or intended (4%) in English (22%), Spanish (23%), or both (55%). The focus of training was as follows: how to remain healthy at work (91%) and at home (60%), what to do if a worker gets sick (77%), and sick leave information (54%). Nevertheless, 18% of the respondents answered that training was not going to be provided. The following control measures implemented: providing hand sanitizer or disinfectant wipes (78%), instruction on frequent hand-washing (76%), social distancing (59%), prevention of employee gatherings (54%), providing and requiring the use of face masks (49%), and limiting on-farm visitors (44%). Multiple correspondence analysis showed that concern with health risk and business impact of the COVID-19 pandemic, as well as mitigation and response strategies implemented, varied based on respondent's dairy size and state. The greatest concerns were reported by producers from California and large and medium-large dairies, whereas the fewest concerns were reported by producers from small dairies. Results from this survey highlighted the health and business concerns of dairy producers from California, Idaho, South Dakota, and Washington during the COVID-19 pandemic and the mitigation efforts adopted. In conclusion, mitigation measures were adopted by most dairy producers but in various degrees. Dairy industry service providers and educators were secondary educational resources during the pandemic; thus, future efforts toward centralized access to dairy specific bilingual educational materials are suggested.
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COVID-19 , Doenças dos Bovinos , Animais , COVID-19/veterinária , California , Bovinos , Indústria de Laticínios , Feminino , Idaho , Pandemias , SARS-CoV-2 , South Dakota , WashingtonRESUMO
The objective was to assess the effectiveness of a comprehensive artificial insemination (AI) training program designed to facilitate an understanding of the breadth of the AI process, including AI skill acquisition, for preclinical veterinary students. Participants (n = 303) were enrolled at the Ross University School of Veterinary Medicine (Basseterre, St. Kitts, West Indies). The 2-d AI training program (n = 20) consisted of â¼8 h of instruction and â¼8 h of demonstration and hands-on activity. Oral presentations were used to deliver educational content, followed by video clips, discussion, demonstrations, and hands-on activity. Reproductive anatomy and physiology of the estrous cycle, AI sire acquisition, collection, evaluation, cryopreservation and distribution of conventional and sexed semen, storage and handling of frozen semen, use of synchronization protocols, accurate and efficient detection of estrus, and correct AI technique were discussed. True or false pre- and posttests were used to determine the level of knowledge gained by participants during the AI training program. Preclinical veterinary students were required to complete a semen handling and AI technique practical exam to achieve a certificate of completion. Participant program evaluations conducted at the conclusion of the program indicated that veterinary students found the content, structure, discussion, demonstrations, and hands-on activities to be appropriate and useful. No negative comments were offered about the training program, instructor, or activity coinstructors. The AI training program increased the posttest knowledge scores of veterinary students by 22 percentage points. Only 1 participant was unable to achieve a certificate of completion due to failure of the semen handling and AI technique practical exam. These results provide evidence that the AI training program was relevant and effective and that it offered information and skill acquisition with immediate field application.
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Detecção do Estro , Inseminação Artificial , Animais , Bovinos , Estro , Sincronização do Estro , Feminino , Humanos , Inseminação Artificial/veterinária , Sêmen , EstudantesRESUMO
We investigate the capacity of published numerical models of thrombin generation to reproduce experimentally observed threshold behavior under conditions in which diffusion and/or flow are important. Computational fluid dynamics simulations incorporating species diffusion, fluid flow, and biochemical reactions are compared with published data for thrombin generation in vitro in 1) quiescent plasma exposed to patches of tissue factor and 2) plasma perfused through a capillary coated with tissue factor. Clot time is correctly predicted in individual cases, and some models qualitatively replicate thrombin generation thresholds across a series of tissue factor patch sizes or wall shear rates. Numerical results suggest that there is not a genuine patch size threshold in quiescent plasma-clotting always occurs given enough time-whereas the shear rate threshold observed under flow is a genuine physical limit imposed by flow-mediated washout of active coagulation factors. Despite the encouraging qualitative results obtained with some models, no single model robustly reproduces all experiments, demonstrating that greater understanding of the underlying reaction network, and particularly of surface reactions, is required. In this direction, additional simulations provide evidence that 1) a surface-localized enzyme, speculatively identified as meizothrombin, is significantly active toward the fluorescent thrombin substrate used in the experiments or, less likely, 2) thrombin is irreversibly inhibited at a faster-than-expected rate, possibly explained by a stimulatory effect of plasma heparin on antithrombin. These results highlight the power of simulation to provide novel mechanistic insights that augment experimental studies and build our understanding of complex biophysicochemical processes. Further validation work is critical to unleashing the full potential of coagulation models as tools for drug development and personalized medicine.
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Trombina , Trombose , Coagulação Sanguínea , Fibrina , Humanos , TromboplastinaRESUMO
Understanding drivers of temporal variation in demographic parameters is a central goal of mark-recapture analysis. To estimate the survival of migrating animal populations in migration corridors, space-for-time mark-recapture models employ discrete sampling locations in space to monitor marked populations as they move past monitoring sites, rather than the standard practice of using fixed sampling points in time. Because these models focus on estimating survival over discrete spatial segments, model parameters are implicitly integrated over the temporal dimension. Furthermore, modeling the effect of time-varying covariates on model parameters is complicated by unknown passage times for individuals that are not detected at monitoring sites. To overcome these limitations, we extended the Cormack-Jolly-Seber (CJS) framework to estimate temporally stratified survival and capture probabilities by including a discretized arrival time process in a Bayesian framework. We allow for flexibility in the model form by including temporally stratified covariates and hierarchical structures. In addition, we provide tools for assessing model fit and comparing among alternative structural models for the parameters. We demonstrate our framework by fitting three competing models to estimate daily survival, capture, and arrival probabilities at four hydroelectric dams for over 200 000 individually tagged migratory juvenile salmon released into the Snake River, USA.
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Teorema de Bayes , Animais , Humanos , Densidade Demográfica , Dinâmica Populacional , ProbabilidadeRESUMO
Wiskott-Aldrich syndrome protein (WASP) family verprolin homologous protein 1 (WAVE1) regulates actin-related protein 2/3 (Arp2/3) complex-mediated actin polymerization. Our previous studies have found WAVE1 to be inhibited by Cdk5-mediated phosphorylation in brain and to play a role in the regulation of dendritic spine morphology. Here we report that mice in which WAVE1 was knocked out (KO) in neurons expressing the D1 dopamine receptor (D1-KO), but not mice where WAVE1 was knocked out in neurons expressing the D2 dopamine receptor (D2-KO), exhibited a significant decrease in place preference associated with cocaine. In contrast to wild-type (WT) and WAVE1 D2-KO mice, cocaine-induced sensitized locomotor behavior was not maintained in WAVE1 D1-KO mice. After chronic cocaine administration and following withdrawal, an acute cocaine challenge induced WAVE1 activation in striatum, which was assessed by dephosphorylation. The cocaine-induced WAVE1 dephosphorylation was attenuated by coadministration of either a D1 dopamine receptor or NMDA glutamate receptor antagonist. Upon an acute challenge of cocaine following chronic cocaine exposure and withdrawal, we also observed in WT, but not in WAVE1 D1-KO mice, a decrease in dendritic spine density and a decrease in the frequency of excitatory postsynaptic AMPA receptor currents in medium spiny projection neurons expressing the D1 dopamine receptor (D1-MSNs) in the nucleus accumbens. These results suggest that WAVE1 is involved selectively in D1-MSNs in cocaine-evoked neuronal activity-mediated feedback regulation of glutamatergic synapses.
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Cocaína/farmacologia , Neurônios/metabolismo , Receptores de Dopamina D1/metabolismo , Comportamento Espacial/efeitos dos fármacos , Família de Proteínas da Síndrome de Wiskott-Aldrich/metabolismo , Animais , Inibidores da Captação de Dopamina/farmacologia , Fenômenos Eletrofisiológicos/genética , Potenciais Pós-Sinápticos Excitadores/genética , Potenciais Pós-Sinápticos Excitadores/fisiologia , Camundongos Knockout , Camundongos Transgênicos , Atividade Motora/efeitos dos fármacos , Atividade Motora/genética , Núcleo Accumbens/metabolismo , Núcleo Accumbens/fisiologia , Fosforilação/efeitos dos fármacos , Receptores de Dopamina D1/genética , Receptores de N-Metil-D-Aspartato/metabolismo , Família de Proteínas da Síndrome de Wiskott-Aldrich/genéticaRESUMO
MSTO1 encodes a cytosolic mitochondrial fusion protein, misato homolog 1 or MSTO1. While the full genotype-phenotype spectrum remains to be explored, pathogenic variants in MSTO1 have recently been reported in a small number of patients presenting with a phenotype of cerebellar ataxia, congenital muscle involvement with histologic findings ranging from myopathic to dystrophic and pigmentary retinopathy. The proposed underlying pathogenic mechanism of MSTO1-related disease is suggestive of impaired mitochondrial fusion secondary to a loss of function of MSTO1. Disorders of mitochondrial fusion and fission have been shown to also lead to mitochondrial DNA (mtDNA) depletion, linking them to the mtDNA depletion syndromes, a clinically and genetically diverse class of mitochondrial diseases characterized by a reduction of cellular mtDNA content. However, the consequences of pathogenic variants in MSTO1 on mtDNA maintenance remain poorly understood. We present extensive phenotypic and genetic data from 12 independent families, including 15 new patients harbouring a broad array of bi-allelic MSTO1 pathogenic variants, and we provide functional characterization from seven MSTO1-related disease patient fibroblasts. Bi-allelic loss-of-function variants in MSTO1 manifest clinically with a remarkably consistent phenotype of childhood-onset muscular dystrophy, corticospinal tract dysfunction and early-onset non-progressive cerebellar atrophy. MSTO1 protein was not detectable in the cultured fibroblasts of all seven patients evaluated, suggesting that pathogenic variants result in a loss of protein expression and/or affect protein stability. Consistent with impaired mitochondrial fusion, mitochondrial networks in fibroblasts were found to be fragmented. Furthermore, all fibroblasts were found to have depletion of mtDNA ranging from 30 to 70% along with alterations to mtDNA nucleoids. Our data corroborate the role of MSTO1 as a mitochondrial fusion protein and highlight a previously unrecognized link to mtDNA regulation. As impaired mitochondrial fusion is a recognized cause of mtDNA depletion syndromes, this novel link to mtDNA depletion in patient fibroblasts suggests that MSTO1-deficiency should also be considered a mtDNA depletion syndrome. Thus, we provide mechanistic insight into the disease pathogenesis associated with MSTO1 mutations and further define the clinical spectrum and the natural history of MSTO1-related disease.
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Proteínas de Ciclo Celular/genética , Doenças Cerebelares/genética , Proteínas do Citoesqueleto/genética , DNA Mitocondrial , Doenças Mitocondriais/genética , Distrofias Musculares/genética , Mutação , Adolescente , Adulto , Atrofia , Células Cultivadas , Doenças Cerebelares/diagnóstico por imagem , Doenças Cerebelares/patologia , Doenças Cerebelares/fisiopatologia , Criança , Variações do Número de Cópias de DNA , Feminino , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Mitocondriais/diagnóstico por imagem , Doenças Mitocondriais/patologia , Doenças Mitocondriais/fisiopatologia , Músculos/patologia , Distrofias Musculares/diagnóstico por imagem , Distrofias Musculares/patologia , Distrofias Musculares/fisiopatologia , Fenótipo , Adulto JovemRESUMO
Milk production traits, such as 305-day milk yield (305MY), have been under direct selection to improve production in dairy cows. Over the past 50 years, the average milk yield has nearly doubled, and over 56% of the increase is attributable to genetic improvement. As such, additional improvements in milk yield are still possible as new loci are identified. The objectives of this study were to detect SNPs and gene sets associated with 305MY in order to identify new candidate genes contributing to variation in milk production. A population of 781 primiparous Holstein cows from six central Washington dairies with records of 305MY and energy corrected milk were used to perform a genome-wide association analysis (GWAA) using the Illumina BovineHD BeadChip (777 962 SNPs) to identify QTL associated with 305MY (P < 1.0 × 10-5 ). A gene set enrichment analysis with SNP data (GSEA-SNP) was performed to identify gene sets (normalized enrichment score > 3.0) and leading edge genes (LEGs) influencing 305MY. The GWAA identified three QTL comprising 34 SNPs and 30 positional candidate genes. In the GSEA-SNP, five gene sets with 58 unique and 24 shared LEGs contributed to 305MY. Identification of QTL and LEGs associated with 305MY can provide additional targets for genomic selection to continue to improve 305MY in dairy cattle.
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Bovinos/genética , Bovinos/fisiologia , Leite , Polimorfismo de Nucleotídeo Único , Animais , Estudo de Associação Genômica Ampla , Locos de Características QuantitativasRESUMO
The objectives were to evaluate pregnancy per artificial insemination (AI), days to first AI, and proportion pregnant within 7 d of AI eligibility in dairy heifers subjected to presynchronization compared with dairy heifers not presynchronized. Thirty days before AI eligibility, Holstein heifers were assigned randomly to 1 of 3 groups: 14-d controlled internal drug release (CIDR; containing progesterone) presynchronization, PGF2α presynchronization, or control (no presynchronization). Heifers in the 14-d CIDR presynchronization treatment (n = 119) received a CIDR on d -30, which was removed on d -16, followed by an injection of PGF2α upon entry to the breeding program (d 0). Heifers in the PGF2α presynchronization treatment (n = 118) received an injection of PGF2α on d -11 and d 0. Control heifers (n = 121) were not presynchronized and received an injection of PGF2α on d 0. All heifers received tail paint on d 0 to facilitate once-daily detection of estrus (based on paint removal). Heifers detected in estrus received AI with conventional semen on the same morning as detected estrus. Generalized linear mixed models were used to assess mean treatment differences. Following PGF2α treatment on d 0, more heifers were detected in estrus in the first 7 d after eligibility in the 14-d CIDR group (95.8%) compared with the PGF2α (74.6%) and control (66.9%) groups. Days to first AI differed between treatments (14-d CIDR = 3.6 d vs. PGF2α = 5.0 d vs. control = 6.8 d). Pregnancy per AI for first AI within 7 d of eligibility was 71.9% (14-d CIDR), 58.0% (PGF2α), and 61.7% (control), and differed between 14-d CIDR and PGF2α heifers. Presynchronization with a 14-d CIDR increased the proportion of heifers pregnant in the first 7 d of eligibility (14-d CIDR = 68.9% vs. PGF2α = 43.2% vs. control = 41.3%). Projected days on feed (d 0 to projected calving date) were 295 (14-d CIDR), 302 (PGF2α), and 305 (control), and were different between the 14-d CIDR and control heifers. The potential economic benefit to the producer was $15.85 per heifer presynchronized with a 14-d CIDR protocol compared with the control group. Treatment of dairy heifers with a 14-d CIDR effectively presynchronized estrus, resulting in a greater proportion detected in estrus, reduced days to first AI, and an increased proportion of heifers pregnant within the first 7 d after breeding eligibility compared with heifers presynchronized with a single PGF2α injection and control heifers.
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Bovinos/fisiologia , Sincronização do Estro/métodos , Progesterona/administração & dosagem , Progestinas/administração & dosagem , Animais , Cruzamento , Dinoprosta/administração & dosagem , Estro/efeitos dos fármacos , Detecção do Estro , Feminino , Inseminação Artificial/veterinária , Gravidez , Taxa de Gravidez , SêmenRESUMO
Using a 5-d controlled internal drug-release (CIDR)-Cosynch resynchronization protocol, the objective of this study was to determine the effect of the initial GnRH injection on pregnancy per artificial insemination (P/AI) to the second artificial insemination in lactating Holstein dairy cows. On 37 ± 3 d (mean ± standard deviation) after the first artificial insemination, and upon nonpregnancy diagnosis (d 0 of the experiment), lactating cows eligible for a second artificial insemination (n = 429) were enrolled in a 5-d CIDR-Cosynch protocol. On d 0, all cows received a CIDR insert and were assigned randomly to receive the initial GnRH injection (GnRH; n = 226) of the protocol or no-GnRH (n = 203). Blood samples were collected from a sub-group of cows (n = 184) on d 0 and analyzed for progesterone (P4) concentration. On d 5, CIDR inserts were removed, and all cows received 1 injection of PGF2α. On d 6 and 7, cows were observed once daily by employees for tail-chalk removal, and cows detected in estrus on d 6 or 7 received artificial insemination that day (EDAI), and did not receive the final GnRH injection. The remaining cows not detected in estrus by d 8 received GnRH and timed artificial insemination (TAI). Pregnancy status was confirmed by transrectal palpation of uterine contents at 37 ± 3 d (mean ± standard deviation) after the second artificial insemination. Eliminating the initial GnRH injection had no effect on P/AI compared with cows receiving GnRH (27 vs. 21%), respectively. Similarly, method of insemination (EDAI vs. TAI) and its interaction with treatment had no effect on P/AI. Primiparous cows had greater P/AI than multiparous cows (31 vs. 21%). Mean P4 concentrations (n = 184) at the initiation of the protocol did not differ between treatments (4.51 ± 0.35 ng/mL no-GnRH vs. 3.96 ± 0.34 ng/mL of GnRH). When P4 concentrations were categorized as high (≥1 ng/mL) or low (<1 ng/mL), P/AI tended to be greater for high P4 concentrations (n = 136) compared with low (n = 48) P4 concentrations (26 vs. 16%, respectively). No differences were observed in the proportion of cows with high or low P4 between treatments. Collectively, these results provide evidence that eliminating the initial GnRH in a 5-d CIDR-Cosynch resynchronization protocol for lactating dairy cows did not reduce P/AI in this study.
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Bovinos , Sincronização do Estro/métodos , Hormônio Liberador de Gonadotropina/administração & dosagem , Resultado da Gravidez/veterinária , Animais , Dinoprosta/sangue , Feminino , Inseminação Artificial/veterinária , Lactação , Gravidez , Progesterona/sangueRESUMO
OBJECTIVES: Mycobacterium tuberculosis is a deadly human pathogen that causes the lung disease TB. M. tuberculosis latently infects a third of the world's population, resulting in â¼1.5 million deaths per year. Due to the difficulties and expense of carrying out animal drug trials using M. tuberculosis and rodents, infections of the zebrafish Danio rerio with Mycobacterium marinum have become a useful surrogate. However, the infection methods described to date require specialized equipment and a high level of operator expertise. METHODS: We investigated whether zebrafish larvae could be naturally infected with bioluminescently labelled M. marinum by immersion, and whether infected larvae could be used for rapid screening of anti-mycobacterial compounds using bioluminescence. We used rifampicin and a variety of nitroimidazole-based next-generation and experimental anti-mycobacterial drugs, selected for their wide range of potencies against M. tuberculosis, to validate this model for anti-mycobacterial drug discovery. RESULTS: We observed that five of the six treatments (rifampicin, pretomanid, delamanid, SN30488 and SN30527) significantly reduced the bioluminescent signal from M. marinum within naturally infected zebrafish larvae. Importantly, these same five treatments also retarded the growth of M. tuberculosis in vitro. In contrast, only three of the six treatments tested (rifampicin, delamanid and SN30527) retarded the growth of M. marinum in vitro. CONCLUSIONS: We have demonstrated that zebrafish larvae naturally infected with bioluminescent M. marinum M can be used for the rapid screening of anti-mycobacterial compounds with readily available equipment and limited expertise. The result is an assay that can be carried out by a wide variety of laboratories for minimal cost and without high levels of zebrafish expertise.
Assuntos
Antituberculosos/isolamento & purificação , Antituberculosos/farmacologia , Avaliação Pré-Clínica de Medicamentos/métodos , Mycobacterium marinum/efeitos dos fármacos , Peixe-Zebra/microbiologia , Animais , Larva/microbiologia , Medições Luminescentes , Mycobacterium marinum/crescimento & desenvolvimento , Nitroimidazóis/farmacologia , Rifampina/farmacologia , Coloração e RotulagemRESUMO
Recurrent axon collaterals are a major means of communication between spiny projection neurons (SPNs) in the striatum and profoundly affect the function of the basal ganglia. However, little is known about the molecular and cellular mechanisms that underlie this communication. We show that intrastriatal nitric oxide (NO) signaling elevates the expression of the vesicular GABA transporter (VGAT) within recurrent collaterals of SPNs. Down-regulation of striatal NO signaling resulted in an attenuation of GABAergic signaling in SPN local collaterals, down-regulation of VGAT expression in local processes of SPNs, and impaired motor behavior. PKG1 and cAMP response element-binding protein are involved in the signal transduction that transcriptionally regulates VGAT by NO. These data suggest that transcriptional control of the vesicular GABA transporter by NO regulates GABA transmission and action selection.
Assuntos
Gânglios da Base/metabolismo , Guanilato Ciclase/química , Neurônios/metabolismo , Óxido Nítrico/química , Transmissão Sináptica/fisiologia , Ácido gama-Aminobutírico/química , Animais , Axônios/metabolismo , AMP Cíclico/metabolismo , Dopamina/metabolismo , Eletrofisiologia , Retroalimentação Fisiológica , Feminino , Proteínas de Fluorescência Verde/metabolismo , Levodopa/química , Masculino , Camundongos , Plasticidade Neuronal , Oxidopamina/química , Transdução de Sinais , Proteínas Vesiculares de Transporte de Aminoácidos Inibidores/metabolismoRESUMO
Levodopa treatment is the major pharmacotherapy for Parkinson's disease. However, almost all patients receiving levodopa eventually develop debilitating involuntary movements (dyskinesia). Although it is known that striatal spiny projection neurons (SPNs) are involved in the genesis of this movement disorder, the molecular basis of dyskinesia is not understood. In this study, we identify distinct cell-type-specific gene-expression changes that occur in subclasses of SPNs upon induction of a parkinsonian lesion followed by chronic levodopa treatment. We identify several hundred genes, the expression of which is correlated with levodopa dose, many of which are under the control of activator protein-1 and ERK signaling. Despite homeostatic adaptations involving several signaling modulators, activator protein-1-dependent gene expression remains highly dysregulated in direct pathway SPNs upon chronic levodopa treatment. We also discuss which molecular pathways are most likely to dampen abnormal dopaminoceptive signaling in spiny projection neurons, hence providing potential targets for antidyskinetic treatments in Parkinson's disease.
Assuntos
Corpo Estriado/efeitos dos fármacos , Discinesia Induzida por Medicamentos/genética , Levodopa/efeitos adversos , Animais , Corpo Estriado/metabolismo , Corpo Estriado/patologia , Dopamina/metabolismo , Expressão Gênica , Homeostase , CamundongosRESUMO
Gross anatomy is considered one of the most important basic science courses in medical education, yet few medical schools require its completion prior to matriculation. The effect of taking anatomy courses before entering medical school on performance in medical gross anatomy has been previously studied with inconsistent results. The effect of premedical anatomy coursework on performance in medical gross anatomy, overall medical school grade point average (GPA), and Comprehensive Osteopathic Medical Licensing Examination Level 1 (COMLEX 1) score was evaluated in 456 first-year osteopathic medical students along with a survey on its perceived benefits on success in medical gross anatomy course. No significant differences were found in gross anatomy grade, GPA, or COMLEX 1 score between students with premedical anatomy coursework and those without. However, significant differences and higher scores were observed in students who had taken three or more undergraduate anatomy courses including at least one with cadaveric laboratory. There was significantly lower perceived benefit for academic success in the medical gross anatomy course (P<.001) from those students who had taken premedical anatomy courses (5.9 of 10) compared with those who had not (8.2 of 10). Results suggest that requiring any anatomy course as a prerequisite for medical school would not have significant effect on student performance in the medical gross anatomy course. However, requiring more specific anatomy coursework including taking three or more undergraduate anatomy courses, one with cadaveric laboratory component, may result in higher medical gross anatomy grades, medical school GPA, and COMLEX 1 scores. Clin. Anat. 30:303-311, 2017. © 2017 Wiley Periodicals, Inc.
Assuntos
Anatomia/educação , Educação de Graduação em Medicina/métodos , Educação Pré-Médica/métodos , Avaliação Educacional/estatística & dados numéricos , Logro , Análise de Variância , Currículo , Educação de Graduação em Medicina/estatística & dados numéricos , Educação Pré-Médica/estatística & dados numéricos , Feminino , Humanos , Modelos Lineares , Masculino , Médicos Osteopáticos/educação , Critérios de Admissão Escolar , Estudantes de MedicinaRESUMO
Fasciolosis, a food-borne trematodiasis, results following infection with the parasites, Fasciola hepatica and Fasciola gigantica. These trematodes greatly affect the global agricultural community, infecting millions of ruminants worldwide and causing annual economic losses in excess of US $3 billion. Fasciolosis, an important zoonosis, is classified by WHO as a neglected tropical disease with an estimated 17 million people infected and a further 180 million people at risk of infection. The significant impact on agriculture and human health together with the increasing demand for animal-derived food products to support global population growth demonstrate that fasciolosis is a major One Health problem. This review details the problematic issues surrounding fasciolosis control, including drug resistance, lack of diagnosis and the threat that hybridization of the Fasciola species poses to future animal and human health. We discuss how these parasites may mediate their long-term survival through regulation and modulation of the host immune system, by altering the host immune homeostasis and/or by influencing the intestinal microbiome particularly in respect to concurrent infections with other pathogens. Large genome, transcriptome and proteomic data sets are now available to support an integrated One Health approach to develop novel diagnostic and control strategies for both animal and human disease.