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1.
BMJ Open Qual ; 12(4)2023 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-38114248

RESUMEN

BACKGROUND: Pill dysphagia, the difficulty in swallowing solid oral medications, is a common problem that can affect medication adherence and increase pill modifications. Current practices of crushing medications or using food vehicles have limitations and potential risks. This report describes the implementation of a medication lubricant, Gloup, for pill dysphagia on an acute care ward using Plan-Do-Study-Act cycles. OBJECTIVE: The objective of this project was to evaluate the implementation of Gloup in the acute care ward setting and assess its acceptability and uptake by patients and ward nurses during medication administration. METHODS: The project involved chart audits of medication administration records, collection of patient feedback, and staff feedback through meetings. Patient characteristics and medication administration practices were documented. The implementation process included education and training sessions for staff, development of a medication chart sticker for evaluation data collection and small-scale testing of Gloup with patients before ward-level implementation. RESULTS: The implementation of Gloup on the acute care ward showed high uptake and acceptability. The majority of patients using Gloup had crushed medications, and the use of Gloup varied based on patient needs. CONCLUSION: The implementation of Gloup as a medication lubricant for pill dysphagia on an acute care ward was successful and well received by patients and staff. The use of Gloup appeared to improve medication administration practices and reduce the need for crushing medications or using food vehicles. This project highlights the importance of addressing pill dysphagia in acute care settings and provides insights for other wards considering similar interventions.


Asunto(s)
Trastornos de Deglución , Humanos , Trastornos de Deglución/tratamiento farmacológico , Preparaciones Farmacéuticas , Hospitales
2.
Cryobiology ; 113: 104579, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37633480

RESUMEN

This work examines the effect of equilibration time with extender on ultra-rapidly frozen-thawed wild ruminant epididymal (origin: Iberian ibex) and ejaculated (origin: mouflon) sperm variables. Sperm samples were prepared either without prior equilibration, or equilibrated for 30 min before freezing. Higher quality (p < 0.05) frozen-thawed spermatozoa were obtained when equilibration was allowed, for ejaculated sperm in terms of sperm motility, acrosome apical ridge integrity, sperm viability, and percentage of normal cells, and for epididymal sperm in terms of linearity and straightness of sperm movement. The sperm head area, head perimeter, head length and head width were smaller (p < 0.01) in the equilibrated than non-equilibrated frozen-thawed epididymal sperm; no such dimensional changes were recorded for ejaculated sperm. In conclusion, equilibration prior to ultra-rapid freezing improves the cryoresistance of sperm cells, although viable sperm cells can be obtained without equilibration. The epididymal sperm showed greater cryoresistance, supporting the idea that it is more resistant to freeze-thawing than ejaculated sperm.


Asunto(s)
Criopreservación , Preservación de Semen , Animales , Masculino , Criopreservación/métodos , Congelación , Motilidad Espermática , Semen , Espermatozoides , Oveja Doméstica , Cabras , Preservación de Semen/veterinaria , Preservación de Semen/métodos
3.
Am J Geriatr Psychiatry ; 31(6): 415-424, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36682987

RESUMEN

OBJECTIVE: Suicide is an outcome arising from a combination of risk and protective factors. Examining psychological resilience traits associated with successful aging may help to better understand late-life suicide and depression. We examined self-reported protective factors including mindfulness, life satisfaction and engagement, flourishing, and subjective and objective social support in a high suicide-risk sample of depressed older adults. METHODS: Participants were 297 individuals aged 55+ (mean age: 64.2): 92 depressed suicide attempters, 138 depressed individuals who never attempted suicide, and 67 non-psychiatric comparisons. Using linear and binomial logistic regression, we examined the effects of a combined Protective Factor value on presence and severity of depression and suicidal ideation, and history of suicide attempt. RESULTS: Relative to the non-psychiatric comparison group, all depressed participants had significantly lower Protective Factor values. Higher Protective Factor value was associated with lower likelihood of depression, depression severity, and likelihood of ideation, but was not associated with ideation severity or history of suicide attempt. Participants with one standard deviation higher Protective Factor had lower odds of ideation incidence by a factor of OR=0.68 (95%CI=0.48-0.96). CONCLUSION: Resiliency characteristics relevant to psychological wellbeing and successful aging may mitigate the emergence of depression and suicidal ideation, as well as the severity of depression in late-life. The Resilience Factor used in this study can help clinicians nuance their appraisal of depression and suicide risk.


Asunto(s)
Atención Plena , Intento de Suicidio , Humanos , Anciano , Intento de Suicidio/prevención & control , Intento de Suicidio/psicología , Ideación Suicida , Depresión/epidemiología , Depresión/psicología , Satisfacción Personal , Factores de Riesgo
4.
Theriogenology ; 189: 230-236, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-35797755

RESUMEN

The expression of aquaglyceroporin 3 (AQP-3) has been demonstrated in the spermatozoa of several mammalian species and its role has been associated with cryotolerance. Post-thaw sperm quality from individual dromedary males with different response to freezing-thawing process was evaluated through sperm head morphometry. In order to understand the cellular mechanisms affected by cryoinjury we have explored the presence and distribution of sperm AQP-3 using western blotting and immunocytochemistry. WB showed different intensity of the specific signal bands at 28 kDa. Immunofluorescence assessments allowed us to identify five different and clear AQP-3 distribution patterns of labelling in the sperm plasma membrane; acrosome, post-acrosome, mid-piece, and principal and final tail. Although expression of AQP-3 varied among male ejaculates, the individual sperm response to freeze-thawing was not associated with AQP-3 expression. Thus, AQP3 expressions do not seem like a reliable predictor of sperm response to freeze-thawing process in this species. This work is the first to describe the morphometric characteristics of the heads of dromedary spermatozoa. No correlation was found between sperm head dimensions and sperm quality variables after freeze-thawing suggesting that dromedary camel sperm head morphometry is also not a reliable predictor of cryosurvival.


Asunto(s)
Camelus , Preservación de Semen , Animales , Acuaporina 3/genética , Acuaporina 3/metabolismo , Camelus/fisiología , Criopreservación/métodos , Criopreservación/veterinaria , Masculino , Preservación de Semen/métodos , Preservación de Semen/veterinaria , Cabeza del Espermatozoide , Motilidad Espermática/fisiología , Espermatozoides/fisiología
5.
Clin Med (Lond) ; 22(3): 218-220, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35584832

RESUMEN

Sickle cell disease is a common inherited disorder that is characterised by chronic haemolysis and vaso-occlusive episodes, resulting in severe pain and end-organ damage. The most frequent acute manifestation of sickle cell disease is a painful vaso-occlusive crisis, which can, in some cases, develop into a sickle chest crisis: a life-threatening complication of sickle cell disease that requires early recognition and prompt intervention to prevent progressive respiratory failure. In addition to the acute complications, patients with sickle cell disease are also at risk of a number of chronic complications that require multidisciplinary specialist input.


Asunto(s)
Anemia de Células Falciformes , Anemia de Células Falciformes/complicaciones , Anemia de Células Falciformes/terapia , Humanos
6.
Vet Med Sci ; 8(3): 1311-1318, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35419978

RESUMEN

BACKGROUND: The Cantabrian capercaillie (Tetrao urogallus cantabricus) is critically endangered. This subspecies has the lowest genetic variability and it is in regression. It belongs to Phasianidae family; therefore, the domestic chicken (Gallus gallus domesticus) could be a good model for developing reproductive technologies for use in capercaillie populations with low availability of animals. OBJECTIVES: In this study, we analyzed the response of capercaillie sperm to the freezing-thawing process for contributing to the development of a semen cryobank of Cantabrian capercaillie. METHODS: We used domestic chicken as the animal model in order to obtain the freezing protocol before applying on capercaillie. In the first experiment, two different extenders (EK and LR84) and different concentrations [4% and 6% dimethyl-acetamide (DMA) v:v] of cryoprotectants were evaluated using in-straw freezing method in domestic chickens. A pilot study in capercaillie males, using the same conditions evaluated in chicken, was performed. RESULTS: In chicken, we found that the LR84-4% DMA media provided the best results for freezing semen. In capercaillie study, LR84 extender seemed to be the most appropriate diluent and 4% was the better dose of DMA cryoprotectant agent. Further, based on previous studies carried out in rooster samples, we also tested the glycerol (8% v/v) as a cryoprotectant for capercaillie semen cryopreservation. CONCLUSIONS: Our results suggest that sperm from both domestic and wild species had a similar response to freezing-thawing processes. Mediterranean chickens may be used as a suitable model for developing sperm freezing protocols that can be extrapolated to threatened capercaillie populations. In addition, LR84 media with glycerol was the most efficient extender to freeze capercaillie sperm native.


Asunto(s)
Pollos , Preservación de Semen , Animales , Pollos/fisiología , Criopreservación/métodos , Criopreservación/veterinaria , Crioprotectores/farmacología , Glicerol , Masculino , Proyectos Piloto , Fitomejoramiento , Semillas , Análisis de Semen/veterinaria , Preservación de Semen/métodos , Preservación de Semen/veterinaria , Motilidad Espermática
7.
Front Vet Sci ; 8: 650946, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34124220

RESUMEN

The domestication process has resulted in profound changes in the reproductive physiology of the animals that might have affected the sperm characteristics and thus their sensitivity to handling and cryopreservation procedures. This work assesses the response of the sperm of domestic and wild ungulates to a cooling storage at 15°C for 20 h followed by incubation at 38.5°C, 5% CO2, for 2 h. In addition, this paper examines the most representative sperm traits to assess their responsiveness to these stress conditions. Sperm samples were collected from domestic and their wild ancestor species: ram, mouflon, buck, Iberian ibex, domestic boar, and wild boar. Sperm motility, viability, mitochondrial membrane status, DNA fragmentation, and reactive oxygen species production were evaluated at the beginning of the experiment, after 20 h of refrigeration at 15°C, and, finally, at 2 h of incubation at 38.5°C. Sperm from all domestic species (ram, buck, and domestic boar) suffered more stress than their wild relatives (mouflon, Iberian Ibex, and wild boar). In pigs, the percentage of intact mitochondria was lower in the domestic species compared to wild boar. In sheep, we found a higher reactive oxygen species production in rams, while in goats, the curvilinear velocity was lower in the domestic species. The PCA (principal components analysis) showed that the motility and their kinetic variables were the most represented variables in the principal components of all species, indicating that they are essential biomarkers for evaluating the stress response. Sperm viability was highlighted as a representative variable for evaluating the stress response in domestic boar, mouflon, ram, and ibex.

9.
J Neuroeng Rehabil ; 18(1): 67, 2021 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-33882948

RESUMEN

BACKGROUND: Extremity weakness, fatigue, and postural instability often contribute to mobility deficits in persons after stroke. Wearable technologies are increasingly being utilized to track many health-related parameters across different patient populations. The purpose of this systematic review was to identify how wearable technologies have been used over the past decade to assess gait and mobility in persons with stroke. METHODS: We performed a systematic search of Ovid MEDLINE, CINAHL, and Cochrane databases using select keywords. We identified a total of 354 articles, and 13 met inclusion/exclusion criteria. Included studies were quality assessed and data extracted included participant demographics, type of wearable technology utilized, gait parameters assessed, and reliability and validity metrics. RESULTS: The majority of studies were performed in either hospital-based or inpatient settings. Accelerometers, activity monitors, and pressure sensors were the most commonly used wearable technologies to assess gait and mobility post-stroke. Among these devices, spatiotemporal parameters of gait that were most widely assessed were gait speed and cadence, and the most common mobility measures included step count and duration of activity. Only 4 studies reported on wearable technology validity and reliability metrics, with mixed results. CONCLUSION: The use of various wearable technologies has enabled researchers and clinicians to monitor patients' activity in a multitude of settings post-stroke. Using data from wearables may provide clinicians with insights into their patients' lived-experiences and enrich their evaluations and plans of care. However, more studies are needed to examine the impact of stroke on community mobility and to improve the accuracy of these devices for gait and mobility assessments amongst persons with altered gait post-stroke.


Asunto(s)
Marcha/fisiología , Accidente Cerebrovascular/fisiopatología , Dispositivos Electrónicos Vestibles , Humanos , Reproducibilidad de los Resultados
11.
Womens Health (Lond) ; 16: 1745506520952285, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32840178

RESUMEN

OBJECTIVES: Assisting patients who are experiencing family violence is an important issue for health services. Rates of screening for family violence in general hospital settings in Australia are unclear. This study was conducted to obtain data on hospital family violence screening rates and health service users' perceptions of the screening process, in a large metropolitan hospital in Australia. METHODS: Clients from the clinical caseloads of social work and psychology staff were invited to participate in a tablet administered, online survey of their family violence screening experiences, within the health service. RESULTS: A total of 59 surveys were completed by hospital users, who had been treated in areas including the emergency department, acute inpatient wards, sub-acute and rehabilitation units, and outpatient clinics. Less than half the sample reported being screened for family violence at the health service. One-quarter of the respondents reported disclosing family violence concerns, with one-fifth wanting to disclose, but not feeling comfortable to do so. The majority of respondents who disclosed family violence felt supported by the response of the staff member and were provided with information they found helpful. However, further work could be done to improve screening rates, environmental and organizational factors to promote users feeling comfortable to disclose, and staff responses to disclosures. CONCLUSION: The results of the survey will be used to inform the development of a hospital-wide family violence training initiative aimed to improve staff knowledge, confidence, rates of screening, and clinical responses to family violence.


Asunto(s)
Violencia Doméstica/estadística & datos numéricos , Hospitales Urbanos/estadística & datos numéricos , Tamizaje Masivo/estadística & datos numéricos , Adulto , Australia , Revelación , Violencia Doméstica/psicología , Femenino , Humanos , Encuestas y Cuestionarios
12.
Womens Health (Lond) ; 16: 1745506520926051, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32716732

RESUMEN

OBJECTIVES: Family violence is a public health issue. It occurs in many forms, is most commonly directed at woman and children, and contributes significantly to death, disability, and illness. This study was conducted in the clinical staff in a large metropolitan hospital and aimed to determine levels of family violence training, self-perceived knowledge and confidence, specific clinical skills, and barriers to working effectively in the area. METHODS: A short, targeted online survey was designed to capture the required information. Descriptive statistics were calculated, and free-text responses were analyzed using qualitative content analysis. RESULTS: Survey responses were received from 534 staff (242 nurses, 225 allied health, 67 medical). Sixty-five percent had received some form of family violence training, mostly of short duration (1-3 h); 72% reported having little or no confidence working in the area, while 76% indicated that they had little or no knowledge in the area. Longer duration training was associated with an increase in knowledge and confidence ratings. Family violence screening rates and knowledge of several specific family violence clinical skills (how to appropriately ask clients about family violence and family violence risk factors) were also low. Thirty-four percent indicated that they did not know what to do, when a patient disclosed experiencing family violence. The most commonly indicated barriers to working effectively in this area were suspected perpetrators being present, perceived reluctance of patients/clients to disclose when asked, and time limitations. CONCLUSION: This research provides a useful snapshot of clinical staff perceptions of their family violence skill levels in a large metropolitan Australian tertiary hospital. It highlights the need for further in-depth training in clinical health professionals in family violence. The research will allow for family violence training to be tailored to the needs of the professional discipline and clinical area.


Asunto(s)
Violencia Doméstica , Conocimientos, Actitudes y Práctica en Salud , Personal de Salud/educación , Australia , Personal de Salud/psicología , Hospitales Urbanos , Humanos , Tamizaje Masivo , Encuestas y Cuestionarios
13.
Reprod Fertil Dev ; 31(10): 1545-1557, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31182186

RESUMEN

The aim of this study was to examine ovine sperm cryoresistance during the rutting season (RS) and its association with sperm head area and seminiferous epithelium proliferation. Small ruminants show fluctuating testosterone levels throughout the year, which could interfere with spermatogenesis and sperm cryopreservation. Ejaculates, testicular biopsies and blood were collected during the middle and at the end of the RS (Middle-RS vs End-RS) during periods of high and low testosterone levels in Merino and Mouflon rams. Fresh and frozen-thawed sperm quality, sperm morphometry, seminiferous tubule morphometry and testicular proliferation markers (proliferating cell nuclear antigen, proliferation marker protein Ki-67 and transcription factor GATA-4) were evaluated. Post-thaw sperm viability was higher in the End-RS group in both Merino (69.9±8.2 vs 41.6±7.3%; P=0.020) and Mouflon rams (40.9±3.3 vs 24.2±5.0%; P=0.008). Mouflons had larger sperm head area at the End-RS (38.3±0.2 vs 34.3±0.1µm2; P=0.029), whereas there was no difference between Merino groups (35.7±0.5 vs 34.8±1.0µm2). Seminiferous tubule morphometry and proliferation markers showed higher levels of germinal epithelium proliferation in the Middle-RS of both species. In conclusion, sperm freezability is affected during the RS in domestic and wild rams, which could be correlated with changes that occur during spermatogenesis, since there is an effect of season on cell proliferation in the testis.


Asunto(s)
Criopreservación , Estaciones del Año , Epitelio Seminífero/fisiología , Ovinos , Espermatozoides , Testículo/citología , Animales , Animales Domésticos , Animales Salvajes , Criopreservación/veterinaria , Congelación , Masculino , Análisis de Semen/veterinaria , Preservación de Semen/normas , Preservación de Semen/veterinaria , Epitelio Seminífero/citología , Oveja Doméstica
15.
Oncotarget ; 7(32): 52375-52391, 2016 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-27447568

RESUMEN

Over 20% of cancer patients will suffer metastatic spread to the brain, and prognosis remains poor. Communication between tumour cells and host tissue is essential during metastasis, yet little is known of the processes underlying such interactions in the brain.Here we test the hypothesis that cross-talk between tumour cells and host brain cells, through tumour cell leukocyte function associated protein-1 (LFA-1), is critical in metastasis development. Temporal expression of LFA-1 and its major ligand intercellular adhesion molecule-1 (ICAM-1) was determined in two different mouse models of brain metastasis. Marked upregulation of both proteins was found, co-localising with astrocytes, microglia and tumour cells themselves. Silencing of LFA-1 expression in MDA231Br-GFP cells prior to intracerebral injection resulted in > 70% reduction in tumour burden compared to control MDA231Br-GFP cells (p < 0.005, n = 5). Subsequent qRT-PCR analysis of brain tissue revealed significant reductions in COX-2, VEGF and eNOS from host brain tissue, but not tumour cells, in mice injected with LFA-1 knockdown cells (p < 0.0001, n = 5). Finally, expression of both LFA-1 and ICAM-1 was demonstrated in human brain metastasis samples.The results of this study suggest LFA-1 as a new target in brain metastasis therapy and highlight the potential synergy with current anti-COX-2 and anti-NOS therapies.


Asunto(s)
Neoplasias Encefálicas/secundario , Ciclooxigenasa 2/metabolismo , Antígeno-1 Asociado a Función de Linfocito/metabolismo , Óxido Nítrico Sintasa de Tipo III/metabolismo , Receptor Cross-Talk/fisiología , Animales , Neoplasias Encefálicas/metabolismo , Línea Celular Tumoral , Regulación hacia Abajo , Femenino , Xenoinjertos , Humanos , Molécula 1 de Adhesión Intercelular/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones SCID
16.
Ther Adv Hematol ; 5(6): 187-96, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25469209

RESUMEN

In the mythology of Ancient Greece, there was often a creative tension between the opposing forces of the gods Apollo and Dionysius, the two sons of Zeus. The Apollonian force was considered to be rational and lifegiving, whilst Dionysian forces were chaotic and elemental. Acute myeloid leukaemia is characterised by the clash of these forces: the chaotic proliferation of immature myeloid cells in the bone marrow overcomes the normal, orderly production of healthy blood cells. DNMT3A mutations occur early in the leukaemogenic process and may even act as "founder" mutations - the first step in a pathway towards malignant transformation. As such, these mutations may represent a Dionysian agent of disorder, inciting the chaotic myeloid proliferation and arrest of differentiation which are hallmarks of AML. This review will focus on the role of DNMT3A mutations in leukaemia pathogenesis, their influence on prognosis, and the potential for therapeutic targeting.

17.
Bone Marrow Res ; 2014: 526568, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25295194

RESUMEN

Molecular studies have shown that multiple myeloma is a highly genetically heterogonous disease which may manifest itself as any number of diverse subtypes each with variable clinicopathological features and outcomes. Given this genetic heterogeneity, a universal approach to treatment of myeloma is unlikely to be successful for all patients and instead we should strive for the goal of personalised therapy using rationally informed targeted strategies. Current DNA sequencing technologies allow for whole genome and exome analysis of patient myeloma samples that yield vast amounts of genetic data and provide a mutational overview of the disease. However, the clinical utility of this information currently lags far behind the sequencing technology which is increasingly being incorporated into clinical practice. This paper attempts to address this shortcoming by proposing a novel genetically based "traffic-light" risk stratification system for myeloma, termed the RAG (Red, Amber, Green) model, which represents a simplified concept of how complex genetic data may be compressed into an aggregate risk score. The model aims to incorporate all known clinically important trisomies, translocations, and mutations in myeloma and utilise these to produce a score between 1.0 and 3.0 that can be incorporated into diagnostic, prognostic, and treatment algorithms for the patient.

18.
Adv Hematol ; 2014: 864058, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24803933

RESUMEN

Multiple myeloma is a malignant proliferation of monoclonal plasma cells leading to clinical features that include hypercalcaemia, renal dysfunction, anaemia, and bone disease (frequently referred to by the acronym CRAB) which represent evidence of end organ failure. Recent evidence has revealed myeloma to be a highly heterogeneous disease composed of multiple molecularly-defined subtypes each with varying clinicopathological features and disease outcomes. The major division within myeloma is between hyperdiploid and nonhyperdiploid subtypes. In this division, hyperdiploid myeloma is characterised by trisomies of certain odd numbered chromosomes, namely, 3, 5, 7, 9, 11, 15, 19, and 21 whereas nonhyperdiploid myeloma is characterised by translocations of the immunoglobulin heavy chain alleles at chromosome 14q32 with various partner chromosomes, the most important of which being 4, 6, 11, 16, and 20. Hyperdiploid and nonhyperdiploid changes appear to represent early or even initiating mutagenic events that are subsequently followed by secondary aberrations including copy number abnormalities, additional translocations, mutations, and epigenetic modifications which lead to plasma cell immortalisation and disease progression. The following review provides a comprehensive coverage of the genetic and epigenetic events contributing to the initiation and progression of multiple myeloma and where possible these abnormalities have been linked to disease prognosis.

19.
Adv Hematol ; 2014: 103175, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24778653

RESUMEN

Acute myeloid leukemia (AML) is a genetically heterogeneous disease. Certain cytogenetic and molecular genetic mutations are recognized to have an impact on prognosis, leading to their inclusion in some prognostic stratification systems. Recently, the advent of high-throughput whole genome or exome sequencing has led to the identification of several novel recurrent mutations in AML, a number of which have been found to involve genes concerned with epigenetic regulation. These genes include in particular DNMT3A, TET2, and IDH1/2, involved with regulation of DNA methylation, and EZH2 and ASXL-1, which are implicated in regulation of histones. However, the precise mechanisms linking these genes to AML pathogenesis have yet to be fully elucidated as has their respective prognostic relevance. As massively parallel DNA sequencing becomes increasingly accessible for patients, there is a need for clarification of the clinical implications of these mutations. This review examines the literature surrounding the biology of these epigenetic modifying genes with regard to leukemogenesis and their clinical and prognostic relevance in AML when mutated.

20.
J Cell Physiol ; 229(10): 1378-86, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24648036

RESUMEN

Animals with external fertilization, as amphibians, store their sperm in a quiescent state in the testis. When spermatozoa are released into natural fertilization media, the hypotonic shock triggers activation of sperm motility. Rhinella (Bufo) arenarum sperm are immotile in artificial seminal plasma (ASP, resembling testicular plasma tonicity) but acquire in situ flagellar beating upon dilution. However, if components from the egg shelly coat are added to this medium, motility shifts to a progressive pattern. Recently, we have shown that the signal transduction pathway required for in situ motility activation involves a rise in intracellular cAMP through a transmembrane adenylyl cyclase and activation of PKA, mostly in the midpiece and in the sperm head. In this report, we demonstrate that activation of calcineurin (aka PP2B and PPP3) is required for the shift from in situ to progressive sperm motility. The effect of calcineurin is manifested by dephosphorylation of PKC substrates, and can be promoted by intracellular calcium rise by Ca(2+) ionophore. Both phosphorylated PKC substrates and calcineurin localized to the flagella, indicating a clear differentiation between compartmentalization of PKA and calcineurin pathways. Moreover, no crosstalk is observed between these signaling events, even though both pathways are required for progressive motility acquisition as discussed.


Asunto(s)
Proteínas Anfibias/metabolismo , Bufo arenarum/metabolismo , Calcineurina/metabolismo , Proteína Quinasa C/metabolismo , Transducción de Señal , Motilidad Espermática , Espermatozoides/enzimología , Animales , Inhibidores de la Calcineurina , Ionóforos de Calcio/farmacología , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Inhibidores Enzimáticos/farmacología , Flagelos/enzimología , Masculino , Presión Osmótica , Fosforilación , Transducción de Señal/efectos de los fármacos , Pieza Intermedia del Espermatozoide/enzimología , Motilidad Espermática/efectos de los fármacos , Cola del Espermatozoide/enzimología , Espermatozoides/efectos de los fármacos , Especificidad por Sustrato
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