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1.
Proteomics ; 24(14): e2300522, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38807556

RESUMO

The mammalian ejaculate is very well suited to proteomics studies. As such, research concerning sperm proteomics is offering a huge amount of new information on the biology of spermatozoa. Among domestic animals, horses represent a species of special interest, in which reproductive technologies and a sizeable market of genetic material have grown exponentially in the last decade. Studies using proteomic approaches have been conducted in recent years, showing that proteomics is a potent tool to dig into the biology of the stallion spermatozoa. The aim of this review is to present an overview of the research conducted, and how these studies have improved our knowledge of stallion sperm biology. The main outcomes of the research conducted so far have been an improved knowledge of metabolism, and its importance in sperm functions, the impact of different technologies on the sperm proteome, and the identification of potential biomarkers. Moreover, proteomics of seminal plasma and phosphoproteomics are identified as areas of major interest.


Assuntos
Proteômica , Espermatozoides , Animais , Cavalos , Masculino , Espermatozoides/metabolismo , Proteômica/métodos , Proteoma/metabolismo , Proteoma/análise , Biomarcadores/metabolismo
2.
Reproduction ; 167(1)2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37870246

RESUMO

In brief: Although common in many commercial extenders, supraphysiological concentrations of glucose in the media may be detrimental to stallion spermatozoa. In this study, we present evidence that these elevated glucose levels may predispose spermatozoa to ferroptosis. Abstract: Stallion spermatozoa depend on oxidative phosphorylation as their major source of ATP; however, the metabolism of these cells is complex and a great degree of metabolic plasticity exists. The composition of the media in which the spermatozoa are extended, or exposed to in the mare's reproductive tract, exerts a profound effect on sperm function and may even accelerate cell demise. Recent research indicates that high concentrations of glucose in the media, although common in commercial extenders, may be detrimental. To determine if supraphysiological glucose concentration may induce or predispose to ferroptosis (a caspase-independent form of programmed cell death, triggered by oxidative stress), stallion spermatozoa were incubated under different concentrations of glucose, 67 mM (HG) or 1 mM plus 10 mM pyruvate (LG-HP), in the presence or absence of known inductors of ferroptosis. Furthermore, we developed a single-cell flow metabolic assay to identify different metabolic phenotypes in spermatozoa. Storage and incubation of spermatozoa under high glucose concentrations led to an increase in the percentage of necrotic spermatozoa (P < 0.0001). Moreover, ferroptosis was induced more intensely in sperm in media with high glucose concentrations (P < 0.0001). Finally, we observed that induction of ferroptosis modified two proteins (oxoglutarate dehydrogenase and superoxide dismutase 2) in spermatozoa incubated in media containing 67 mM glucose but not in media containing 1 mM glucose and 10 mM pyruvate. The composition of the media, especially the concentration of glucose, exerts a major impact on the functionality and life span of the spermatozoa. The results reported here may pave the way for improvements in existing semen extenders.


Assuntos
Ferroptose , Preservação do Sêmen , Animais , Cavalos , Masculino , Feminino , Glucose/farmacologia , Glucose/metabolismo , Sêmen , Espermatozoides/metabolismo , Ácido Pirúvico/farmacologia , Ácido Pirúvico/metabolismo , Motilidade dos Espermatozoides , Preservação do Sêmen/métodos
3.
Inj Prev ; 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39060115

RESUMO

Recognising and removing players with suspected sport-related concussions is crucial for community sports. OBJECTIVES: Quantify rates and factors associated with non-reporting of concussion symptoms in community rugby league. METHODS: Overall, 484 community rugby league players aged ≥18 years and 965 parents of rugby league players aged <18 years completed an online survey, regarding concussion history, knowledge, prevalence and reasons for non-reporting of concussion, long-term implications and perceptions of concussion. RESULTS: Thirty-five percent of players aged ≥18 years and 22% of parents of players aged <18 years reported at least one concussion in the last two seasons. Forty-three percent of players aged ≥18 years and 5% of parents of players aged<18 years surveyed stated they did not report concussion-related symptoms sustained during 2020 and 2021 seasons. The two most common reasons for non-reporting of concussion symptoms were 'didn't want to be ruled out of a match' and 'didn't want to let down the team'. Players aged ≥18 years who received external coaching pressures around concussion were more likely to not report concussion symptoms. Over 40% of parents and players were concerned about the potential long-term implications. Ten percent of players aged ≥18 years and 7% of parents of players aged <18 years would encourage their family members/children to not play rugby league. CONCLUSIONS: Non-reporting rates of suspected concussion symptoms in adult community players were twice as high as in professional rugby league, with similar reasons (wanting to play and not letting the team down). Engaging coaches to prioritise brain health and providing broader and appropriate education on concussion should be focused on, given the concerns reported by community players and parents.

4.
Biol Reprod ; 108(2): 324-337, 2023 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-36468681

RESUMO

Although recent research has addressed the impact of cryopreservation on the stallion sperm proteome, studies addressing the stallion sperm phosphoproteome are lacking. In the present study, the data set of proteomes of fresh and cryopreserved spermatozoa were reanalyzed, showing that cryopreservation caused significant changes in the phosphoproteome. The phosphoproteins reduced most significantly by cryopreservation were Ca2+binding tyrosine phosphorylation regulated, protein kinase cAMP-activated catalytic subunit beta (CABYR), mitochondria eating protein (SPATA18), A kinase anchoring protein 4 (AKAP4), A-kinase anchoring protein 3 (AKAP3) and the Family with sequence similarity 71 member B (FAM71B). These proteins belong to the gene ontology (GO) terms sperm fibrous sheath (GO: 0035686), and sperm principal piece (GO: 0097228). The regulatory interactions between kinases and phosphorylation sites on the proteins that were affected most were also investigated, and the potential kinases (based on human orthologs) involved in the regulation of these phosphoproteins identified were: PKCß for SPATA18 and GSK3ß for CABYR. Kinase inhibition assays were also conducted showing that kinases phosphorylating the above-mentioned proteins play an important role in their activity and thus, phosphorylation controls the activity of these proteins and their role in the regulation of the functionality and viability of stallion spermatozoa. In conclusion, the data reported here contribute to the understanding of the fact that the dephosphorylation of certain proteins is a molecular lesion induced by cryopreservation in the stallion spermatozoa.


Assuntos
Preservação do Sêmen , Sêmen , Masculino , Animais , Cavalos , Humanos , Sêmen/metabolismo , Espermatozoides/metabolismo , Cauda do Espermatozoide/metabolismo , Fosforilação , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Criopreservação/veterinária , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides/fisiologia , Proteínas de Ancoragem à Quinase A
5.
Br J Sports Med ; 2022 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-35879022

RESUMO

OBJECTIVES: Assess the validity and feasibility of current instrumented mouthguards (iMGs) and associated systems. METHODS: Phase I; four iMG systems (Biocore-Football Research Inc (FRI), HitIQ, ORB, Prevent) were compared against dummy headform laboratory criterion standards (25, 50, 75, 100 g). Phase II; four iMG systems were evaluated for on-field validity of iMG-triggered events against video-verification to determine true-positives, false-positives and false-negatives (20±9 player matches per iMG). Phase III; four iMG systems were evaluated by 18 rugby players, for perceptions of fit, comfort and function. Phase IV; three iMG systems (Biocore-FRI, HitIQ, Prevent) were evaluated for practical feasibility (System Usability Scale (SUS)) by four practitioners. RESULTS: Phase I; total concordance correlation coefficients were 0.986, 0.965, 0.525 and 0.984 for Biocore-FRI, HitIQ, ORB and Prevent. Phase II; different on-field kinematics were observed between iMGs. Positive predictive values were 0.98, 0.90, 0.53 and 0.94 for Biocore-FRI, HitIQ, ORB and Prevent. Sensitivity values were 0.51, 0.40, 0.71 and 0.75 for Biocore-FRI, HitIQ, ORB and Prevent. Phase III; player perceptions of fit, comfort and function were 77%, 6/10, 55% for Biocore-FRI, 88%, 8/10, 61% for HitIQ, 65%, 5/10, 43% for ORB and 85%, 8/10, 67% for Prevent. Phase IV; SUS (preparation-management) was 51.3-50.6/100, 71.3-78.8/100 and 83.8-80.0/100 for Biocore-FRI, HitIQ and Prevent. CONCLUSION: This study shows differences between current iMG systems exist. Sporting organisations can use these findings when evaluating which iMG system is most appropriate to monitor head acceleration events in athletes, supporting player welfare initiatives related to concussion and head acceleration exposure.

6.
Br J Sports Med ; 56(2): 68-79, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33619127

RESUMO

The cessation of amateur and recreational sport has had significant implications globally, impacting economic, social and health facets of population well-being. As a result, there is pressure to resume sport at all levels. The ongoing prevalence of SARS-CoV-2 and subsequent 'second waves' require urgent best practice guidelines to be developed to return recreational (non-elite) sports as quickly as possible while prioritising the well-being of the participants and support staff.This guidance document describes the need for such advice and the process of collating available evidence. Expert opinion is integrated into this document to provide uniform and pragmatic recommendations, thereby optimising on-field and field-side safety for all involved persons, including coaches, first responders and participants.The nature of SARS-CoV-2 transmission means that the use of some procedures performed during emergency care and resuscitation could potentially be hazardous, necessitating the need for guidance on the use of personal protective equipment, the allocation of predetermined areas to manage potentially infective cases and the governance and audit of the process.


Assuntos
COVID-19 , Pandemias , Consenso , Primeiros Socorros , Humanos , SARS-CoV-2
7.
Reprod Domest Anim ; 57 Suppl 5: 34-44, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35748405

RESUMO

Ultrasound technology has led to new lines of research in equine reproduction, and it has helped to greatly improve clinical diagnosis and reproductive outcomes in equine practice. This review aims to discuss the potential clinical uses and new approaches of ultrasonography in equine reproduction. Doppler modalities are usually used to evaluate the vascularization of the follicles, corpus luteum (CL), and the uterus in the mare for diagnostic purposes. Inclusion of Doppler ultrasound in artificial insemination and embryo transfer programs could improve the reproductive outcome of these techniques. Better selection of recipients based on CL functionality, early pregnancy diagnosis 7-8 days postovulation of the donor before flushing or diagnosis of mares with endometritis with pathological increases of blood flow are examples of clinical applications in the mare. In the stallion, colour Doppler ultrasound has improved the diagnostic potential of B-mode ultrasound, improving the differential diagnosis of pathologies such as testicular torsion (decrease or absence of blood flow in the cord) and orchitis (increased blood flow in the cord). The incorporation of pulsed Doppler ultrasound into the reproductive evaluation of the stallion has enabled early identification of stallions with testicular dysfunction, thus allowing administration of timely treatment and subsequent improvements of the fertility prognosis for these animals. In addition, this technique has been used in the monitoring of patients undergoing medical and surgical treatments, thus verifying their efficacy. Recently, computer-assisted pixel analysis using specific software has been performed in research work in order to semi-quantitatively evaluate the vascularization (colour and power Doppler) and echotexture of different organs. These softwares are now being developed for clinical purposes, as is the case with Ecotext, a computer program developed for the evaluation of testicular echotexture, providing information on testicular functionality.


Assuntos
Corpo Lúteo , Medicina Reprodutiva , Animais , Corpo Lúteo/irrigação sanguínea , Feminino , Cavalos , Inseminação Artificial/veterinária , Masculino , Gravidez , Ultrassonografia/veterinária , Ultrassonografia Doppler em Cores
8.
Reprod Domest Anim ; 57 Suppl 5: 98-102, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35467047

RESUMO

In this study, uterine blood flow area (BFA) has been evaluated for the first time using power Doppler ultrasound (PD) as a marker of endometritis in mares and jennies. The uterine BFA in healthy mares was greater in oestrus than in diestrus (p < .001). However, differences in endometrial blood flow between oestrus and diestrus were not observed in mares with endometritis. The uterine blood flow in healthy jennies is not affected by the oestrus cycle. Both species showed an increase in endometrial BFA in pathological uterine conditions compared to controls. BFA was a good marker of endometritis with an area under curve (AUC) (estrus:0.94 (p < .001) diestrus:0.98 (p < .001) in mares and AUC (0.91 (p < .0001) in jennies. The results of this preliminary study suggest that PD ultrasound in combination with computerized image analysis has the potential to be a very useful tool in the diagnosis of endometritis.


Assuntos
Endometrite , Doenças dos Cavalos , Animais , Endometrite/diagnóstico por imagem , Endometrite/veterinária , Endométrio/diagnóstico por imagem , Equidae , Feminino , Doenças dos Cavalos/diagnóstico por imagem , Cavalos , Útero/irrigação sanguínea
9.
J Sports Sci ; 40(13): 1436-1449, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35694782

RESUMO

This study aimed to 1) develop a consensus (≥70% agreement between experts) on injury risk factors specific to women playing rugby league, 2) establish the importance of the identified injury risk factors and the feasibility of mitigating these risk factors and 3) establish context specific barriers to injury risk management. Aim 1: A Delphi panel, consisting of 12 experts in rugby league and injury (e.g., physiotherapists, research scientists) were asked to identify injury risk factors specific to women playing rugby league. Aim 2: seven coaches of women's rugby league teams were asked to rate each risk factor that achieved consensus by their importance and feasibility to manage. Aim 3: Coaches reported barriers which restrict injury risk factor mitigation. Of the 53 injury risk factors which achieved consensus, the five injury risk factors with the highest combination of importance and feasibility ratings were: "poor tackle technique", "a lack of pre-season intensity", "training session are too short", "the current medical standards", and "limited access to physiotherapists". Following the identification of injury risk factors, their feasibility to manage and context specific barriers, this study proposes three constraint driven, integrated solutions which may reduce the barriers which limit injury risk factor management.


Assuntos
Traumatismos em Atletas , Futebol Americano , Traumatismos em Atletas/prevenção & controle , Técnica Delphi , Feminino , Futebol Americano/lesões , Humanos , Fatores de Risco , Rugby
10.
Nutr Health ; 28(4): 483-487, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34747244

RESUMO

Background: Advances in medical technology have resulted in changes to enteral tube feeding (ETF). Standard practice in the UK is to use commercial formula for ETF via the stomach or small intestine; however, blended diets are becoming increasingly popular. Emerging evidence shows benefits of a blended diet although evidence informing clinical guidance is sparse. Consequently, there is disparity in practice, and it remains unclear which patient groups may benefit most from a blended diet. Aim: To demonstrate the initiation of a blended diet in clinical practice. Methods: This case report features a 2-year-old child requiring ETF in the context of hypotonia, developmental delay and faltering growth. Results: In this instance, a blended diet resulted in improved gastrointestinal symptoms and adequate growth. Conclusion: This case demonstrates the successful implementation of a blended diet and associated benefits. Blended diets may benefit others requiring ETF and should be considered on an individualised basis.


Assuntos
Nutrição Enteral , Pediatria , Criança , Humanos , Pré-Escolar , Nutrição Enteral/métodos , Gastrostomia/métodos , Alimentos Formulados , Dieta/métodos
11.
J Proteome Res ; 20(5): 2435-2446, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33656888

RESUMO

Although cryopreservation is widely used in animal breeding, the technique is still suboptimal. The population of spermatozoa surviving the procedure experiences changes attributed to alteration in their redox regulation. In order to expand our knowledge regarding this particular aspect, the proteome in fresh and frozen thawed aliquots of equine spermatozoa was studied to identify the proteins most severely affected by the procedure. If alteration of redox regulation is a major factor explaining cryodamage, proteins participating in redox regulation should be principally affected. Using a split sample design, 30 ejaculates from 10 different stallions were analyzed as fresh spermatozoa, and another aliquot from the same ejaculate was analyzed as a frozen thawed sample. The proteome was studied under both conditions using UHPLC-MS/MS and bioinformatic analysis conducted to identify discriminant variables between both conditions. Data are available through the ProteomeXchange Consortium with identifier PXD022236. The proteins most significantly reduced were Aldo-keto reductase family 1 member B (p = 2.2 × 10-17) and Superoxide dismutase (Cu-Zn) (p = 4.7 × 10-14). This is the first time that SOD1 has been identified as a discriminating variable using bioinformatic analysis, where it was one of the most highly significantly different proteins seen between fresh and frozen thawed semen. This finding strongly supports the theory that alteration in redox regulation and oxidative stress is a major factor involved in cryodamage and suggests that control of redox regulation should be a major target to improve current cryopreservation procedures.


Assuntos
Criopreservação , Espectrometria de Massas em Tandem , Aldeído Redutase , Animais , Cavalos , Masculino , Oxirredutases , Motilidade dos Espermatozoides , Espermatozoides , Superóxido Dismutase/genética , Superóxido Dismutase-1/genética
12.
Biol Reprod ; 105(2): 519-532, 2021 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-33864078

RESUMO

Energy metabolism in spermatozoa is complex and involves the metabolism of carbohydrate fatty acids and amino acids. The ATP produced in the electron transport chain in the mitochondria appears to be crucial for both sperm motility and maintaining viability, whereas glycolytic enzymes in the flagella may contribute to ATP production to sustain motility and velocity. Stallion spermatozoa seemingly use diverse metabolic strategies, and in this regard, a study of the metabolic proteome showed that Gene Ontology terms and Reactome pathways related to pyruvate metabolism and the Krebs cycle were predominant. Following this, the hypothesis that low glucose concentrations can provide sufficient support for motility and velocity, and thus glucose concentration can be significantly reduced in the medium, was tested. Aliquots of stallion semen in four different media were stored for 48 h at 18°C; a commercial extender containing 67 mM glucose was used as a control. Stallion spermatozoa stored in media with low glucose (1 mM) and high pyruvate (10 mM) (LG-HP) sustained better motility and velocities than those stored in the commercial extender formulated with very high glucose (61.7 ± 1.2% in INRA 96 vs 76.2 ± 1.0% in LG-HP media after 48 h of incubation at 18°C; P < 0.0001). Moreover, mitochondrial activity was superior in LG-HP extenders (24.1 ± 1.8% in INRA 96 vs 51.1 ± 0.7% in LG-HP of spermatozoa with active mitochondria after 48 h of storage at 18°C; P < 0.0001). Low glucose concentrations may permit more efficient sperm metabolism and redox regulation when substrates for an efficient tricarboxylic acid cycle are provided. The improvement seen using low glucose extenders is due to reductions in the levels of glyoxal and methylglyoxal, 2-oxoaldehydes formed during glycolysis; these compounds are potent electrophiles able to react with proteins, lipids, and DNA, causing sperm damage.


Assuntos
Aldeídos/metabolismo , Metabolismo Energético , Glucose/deficiência , Cavalos/fisiologia , Ácido Pirúvico/metabolismo , Preservação do Sêmen/instrumentação , Espermatozoides/fisiologia , Animais , Masculino , Mitocôndrias , Oxirredução , Motilidade dos Espermatozoides/fisiologia
13.
Biol Reprod ; 104(5): 1097-1113, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33438027

RESUMO

The identification of stallions and or ejaculates that will provide commercially acceptable quality post-thaw before cryopreservation is of great interest, avoiding wasting time and resources freezing ejaculates that will not achieve sufficient quality to be marketed. Our hypothesis was that after bioinformatic analysis, the study of the stallion sperm proteome can provide discriminant variables able to predict the post-thaw quality of the ejaculate. At least three ejaculates from 10 different stallions were frozen following a split sample design. Half of the ejaculate was analyzed as a fresh aliquot and the other half was frozen and then analyzed as a frozen-thawed aliquot. Computer-assisted sperm analysis and flow cytometry were used to analyze sperm quality. Detailed proteomic analysis was performed on fresh and frozen and thawed aliquots, and bioinformatic analysis was used to identify discriminant variables in fresh samples able to predict the outcome of cryopreservation. Those with a fold change > 3, a P = 8.2e-04, and a q = 0.074 (equivalent to False discovery rate (FDR)) were selected, and the following proteins were identified in fresh samples as discriminant variables of good motility post-thaw: F6YTG8, K9K273, A0A3Q2I7V9, F7CE45, F6YU15, and F6SKR3. Other discriminant variables were also identified as predictors of good mitochondrial membrane potential and viability post-thaw. We concluded that proteomic approaches are a powerful tool to improve current sperm biotechnologies.


Assuntos
Criopreservação/veterinária , Cavalos/fisiologia , Proteoma/química , Análise do Sêmen/veterinária , Preservação do Sêmen/veterinária , Espermatozoides/fisiologia , Animais , Masculino , Espermatozoides/química
14.
Br J Sports Med ; 55(14): 807-813, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33574043

RESUMO

OBJECTIVES: To examine the interactions between SARS-CoV-2 positive players and other players during rugby league matches and determine within-match SARS-CoV-2 transmission risk. METHODS: Four Super League matches in which SARS-CoV-2 positive players were subsequently found to have participated were analysed. Players were identified as increased-risk contacts, and player interactions and proximities were analysed by video footage and global positioning system (GPS) data. The primary outcome was new positive cases of SARS-CoV-2 within 14 days of the match in increased-risk contacts and other players participating in the matches. RESULTS: Out of 136 total players, there were 8 SARS-CoV-2 positive players, 28 players identified as increased-risk contacts and 100 other players in the matches. Increased-risk contacts and other players were involved in 11.4±9.0 (maximum 32) and 4.0±5.2 (maximum 23) tackles, respectively. From GPS data, increased-risk contacts and other players were within 2 m of SARS-CoV-2 positive players on 10.4±18.0 (maximum 88) and 12.5±20.7 (maximum 121) occasions, totalling 65.7±137.7 (maximum 689) and 89.5±169.4 (maximum 1003) s, respectively. Within 14 days of the match, one increased-risk contact and five players returned positive SARS-CoV-2 reverse transcriptase PCR (RT-PCR) tests, and 27 increased-risk contacts and 95 other participants returned negative SARS-CoV-2 RT-PCR tests. Positive cases were most likely traced to social interactions, car sharing and wider community transmission and not linked to in-match transmission. CONCLUSION: Despite tackle involvements and close proximity interactions with SARS-CoV-2 positive players, in-match SARS-CoV-2 transmission was not confirmed. While larger datasets are needed, these findings suggest rugby presents a lower risk of viral transmission than previously predicted.


Assuntos
Desempenho Atlético , COVID-19/transmissão , Comportamento Competitivo , Futebol Americano , Sistemas de Informação Geográfica , Humanos , Masculino , Pandemias , SARS-CoV-2
15.
Biol Reprod ; 103(6): 1275-1288, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32857155

RESUMO

Some stallions yield ejaculates that do not tolerate conservation by refrigeration prior to artificial insemination (AI), showing improvement after removal of most of the seminal plasma (SP) by centrifugation. In this study, the SP-proteome of 10 different stallions was defined through high-performance liquid chromatography with tandem mass spectrometry and bioinformatic analysis in relation to the ability of the ejaculates to maintain semen quality when cooled and stored at 5°C. Stallions were classified into three groups, depending on this ability: those maintaining good quality after direct extension in a commercial extender (good), stallions requiring removal of seminal plasma (RSP) to maintain seminal quality (good-RSP), and stallions, unable to maintain good semen quality even after RSP (poor). Pathway enrichment analysis of the proteins identified in whole equine SP using human orthologs was performed using g: profiler showing enriched Reactome and the Kyoto Encyclopedia of Genes and Genomes pathways related to hexose metabolism, vesicle mediated transport, post translational modification of proteins and immune response. Specific proteins overrepresented in stallions tolerating conservation by refrigeration included a peroxiredoxin-6 like protein, and transcobalamin-2, a primary vitamin B12-binding, and transport protein. Also, the protein involved in protein glycosylation, ST3 beta-galactoside alpha-2,3-sialyltransferase 1 was present in good stallions. These proteins were nearly absent in poor stallions. Particularly, annexinA2 appeared as to be the most powerful discriminant variable for identification of stallions needing RSP prior to refrigeration, with a P = 0.002 and a q value = 0.005. Overall this is the first detailed study of the equine SP-proteome, showing the potential value of specific proteins as discriminant bio-markers for clinical classification of stallions for AI.


Assuntos
Anexinas/metabolismo , Cavalos/fisiologia , Refrigeração , Preservação do Sêmen/veterinária , Espermatozoides/fisiologia , Animais , Biomarcadores/química , Sobrevivência Celular/fisiologia , Masculino , Proteínas de Plasma Seminal/química , Proteínas de Plasma Seminal/metabolismo
16.
Reproduction ; 160(6): 803-818, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33112766

RESUMO

Spermatozoa are redox-regulated cells, and stallion spermatozoa, in particular, present an intense mitochondrial activity in which large amounts of reactive oxygen species (ROS) are produced. To maintain the redox potential under physiological conditions, sophisticated mechanisms ought to be present, particularly in the mitochondria. In the present study, we investigated the role of the SLC7A11 antiporter. This antiporter exchanges intracellular glutamate for extracellular cystine. In the spermatozoa, cystine is reduced to cysteine and used for GSH synthesis. The importance of the antiporter for mitochondrial functionality was studied using flow cytometry and UHPLC/MS/MS approaches. Intracellular GSH increased in the presence of cystine, but was reduced in the presence of Buthionine sulphoximine (BSO), a γ-glutamylcysteine synthetase inhibitor (P < 0.001). Inhibition of the SLC7A11 antiporter with sulfasalazine caused a dramatic drop in intracellular GSH (P < 0.001) and in the percentage of spermatozoa showing active mitochondria (P < 0.001). These findings suggest that proper functionality of this antiporter is required for the mitochondrial function of spermatozoa. We also describe that under some conditions, glutamate may be metabolized following non-conventional pathways, also contributing to sperm functionality. We provide evidences, that the stallion spermatozoa have important metabolic plasticity, and also of the relation between redox regulation and metabolic regulation. These findings may have important implications for the understanding of sperm biology and the development of new strategies for sperm conservation and treatment of male factor infertility.


Assuntos
Sistema y+ de Transporte de Aminoácidos/metabolismo , Glutamatos/metabolismo , Metaboloma , Mitocôndrias/fisiologia , Estresse Oxidativo , Espermatozoides/fisiologia , Sistema y+ de Transporte de Aminoácidos/antagonistas & inibidores , Sistema y+ de Transporte de Aminoácidos/genética , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Cistina/metabolismo , Glutationa/metabolismo , Cavalos , Masculino , Mitocôndrias/efeitos dos fármacos , Espermatozoides/citologia , Espermatozoides/efeitos dos fármacos , Sulfassalazina/farmacologia
17.
Br J Sports Med ; 2020 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-33361278

RESUMO

The COVID-19 pandemic has necessitated many novel responses in healthcare including sport and exercise medicine. The cessation of elite sport almost globally has had significant economic implications and resulted in pressure to resume sport in very controlled conditions. This includes protecting pitch-side medical staff and players from infection. The ongoing prevalence of SARS-CoV-2 and the desire to resume professional sport required urgent best practice guidelines to be developed so that sport could be resumed as safely as possible. This set of best practice recommendations assembles early evidence for managing SARS-CoV-2 and integrates expert opinion to provide a uniform and pragmatic approach to enhance on-field and pitch-side safety for the clinician and player. The nature of SARS-CoV-2 transmission creates new hazards during resuscitation and emergency care and procedures. Recommendations for the use and type of personal protective equipment during on-field or pitch-side emergency medical care is provided based on the clinical scenario and projected risk of viral transmission.

18.
J Vet Med Educ ; 44(4): 692-703, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28691867

RESUMO

Today's veterinary students have access to a wide range of online resources that support self-directed learning. To develop a benchmark of current global student practice in e-learning, this study measured self-reported access to, and use of, these resources by students internationally. An online survey was designed and promoted via veterinary student mailing lists and international organizations, resulting in 1,070 responses. Analysis of survey data indicated that students now use online resources in a wide range of ways to support their learning. Students reported that access to online veterinary learning resources was now integral to their studies. Almost all students reported using open educational resources (OERs). Ownership of smartphones was widespread, and the majority of respondents agreed that the use of mobile devices, or m-learning, was essential. Social media were highlighted as important for collaborating with peers and sharing knowledge. Constraints to e-learning principally related to poor or absent Internet access and limited institutional provision of computer facilities. There was significant geographical variation, with students from less developed countries disadvantaged by limited access to technology and networks. In conclusion, the survey provides an international benchmark on the range and diversity in terms of access to, and use of, online learning resources by veterinary students globally. It also highlights the inequalities of access among students in different parts of the world.


Assuntos
Educação em Veterinária/métodos , Internet/estatística & dados numéricos , Aprendizagem , Estudantes de Medicina/psicologia , Saúde Global , Humanos , Fatores Socioeconômicos , Inquéritos e Questionários , Reino Unido
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