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1.
Sci Rep ; 13(1): 19746, 2023 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-37957184

RESUMO

Fish speciation was accompanied by changes in the urogenital system anatomy. In evolutionarily modern Teleostei, male reproductive tracts are fully separated from the excretory system, while in evolutionarily ancient Chondrostei and Holostei, the excretory and reproductive tracts are not separated. Sturgeon post-testicular sperm maturation (PTSM) occurring as a result of sperm/urine mixing is phenomenologically well described, while, in holosteans, functional intimacy of seminal ducts with kidney ducts and the existence of PTSM still need to be addressed. In Lepisosteus platostomus (Holostei), sperm samples were collected from testes (TS), efferent ducts (EDS), and Wolffian ducts (WDS). While WDS was motile, no motility was found in TS and EDS. The existence of PTSM was checked by in vitro PTSM procedure. After TS and EDS incubation in seminal fluid from WDS, no more than 5% motile spermatozoa were observed in TS, whereas in EDS the motility percentage was up to 75%. Experimental dyeing of urogenital ducts in gars and sturgeons revealed some differences in the interconnection between sperm ducts and kidneys. It is concluded that post-testicular sperm maturation occurs in gars and suggests that infraclass Holostei occupies an intermediate evolutionary position between Teleostei and Chondrostei in the anatomical arrangement of the urogenital system.


Assuntos
Maturação do Esperma , Testículo , Animais , Masculino , Sêmen , Espermatozoides , Genitália Masculina , Peixes/anatomia & histologia , Motilidade dos Espermatozoides
2.
Fish Physiol Biochem ; 48(4): 899-910, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35697911

RESUMO

Pikeperch (Sander lucioperca) is a highly profitable commercial species whose economic value has greatly increased in the last decade. As in other species, the quality of spermatozoa in this species is a principal feature inherent in fertilization success and efficient natural and artificial reproduction. The capacity of fish spermatozoa to be activated and tolerate environmental changes (in osmolality, ion composition, external pH, temperature, etc.) during the motility period contributes to fertilization success. In this study, we investigated the effects of environmental osmolality and ion composition on spermatozoa motility. To determine if the activation mechanism is affected by sperm quality parameters, we measured semen characteristics such as semen volume, spermatozoa concentration, seminal fluid osmolality and ion composition, and spermatozoa lipid composition. An additional parameter of sperm quality reflecting spermatozoa osmoresistance, the swelling rate, was measured by the nephelometry method. We detected that sperm samples with the highest content of palmitic (C16:0) and palmitoleic (C16:1) acids showed the lowest motility activation under the studied conditions, suggesting that these fatty acids are possible markers for the determination of spermatozoa quality in fish. Our results show that pikeperch spermatozoa can be activated under different osmotic conditions and that cell swelling always accompanies motility. However, spermatozoa sustain their volume under hypotonic conditions when motility is not initiated, suggesting that pikeperch spermatozoa activation is mainly controlled by ion composition rather than the osmolarity of the surrounding medium.


Assuntos
Percas , Sêmen , Animais , Masculino , Percas/fisiologia , Sêmen/fisiologia , Análise do Sêmen/veterinária , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/fisiologia
3.
Fish Physiol Biochem ; 47(3): 785-795, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34076793

RESUMO

In most fish exhibiting external fertilization, spermatozoa become motile after release into water, triggered by differences between intracellular and extracellular conditions such as osmotic pressure, ion composition, and pH. The rapid change in osmolarity initiating spermatozoon motility induces osmotic pressure, resulting in active water movement across the cell membrane. Mechanisms of ion and water transport across the plasma membrane and cell volume regulation are important in maintaining structure and functional integrity of the cell. The capacity of the fish spermatozoon plasma membrane to adapt to dramatic environmental changes is an essential prerequisite for motility and successful fertilization. Adaptation to change in external osmolality may be the basis of spermatozoon function and an indicator of sperm quality. The involvement of specific water channels (aquaporins) in cell volume regulation and motility is highly likely. The goal of this review is to describe basic mechanisms of water transport and their role in fish spermatozoon physiology, focusing on osmoresistance, cell volume regulation, motility, and survival.


Assuntos
Peixes/fisiologia , Osmorregulação , Espermatozoides/fisiologia , Animais , Aquaporinas/fisiologia , Criopreservação , Humanos , Lipídeos/fisiologia , Masculino , Preservação do Sêmen
4.
Fish Physiol Biochem ; 47(2): 327-338, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33405059

RESUMO

Studying biology of sperm provides valuable information to optimize artificial reproduction and is crucial for sustainable aquaculture. Here, we investigated morphology of spermatozoon in Atlantic cod (Gadus morhua) using transmission and scanning electron microscopy. Furthermore, spermatozoa motility kinetics at different osmolalities were studied using computer-assisted sperm analysis software. The spermatozoon lacked an acrosome and consisted of a head, midpiece, and flagellum. The head of spermatozoa was round, oval, and rather elongated in shape, showing high variations in dimensions. There were up to 6 mitochondria that encircled the proximal part of the flagellum. The proximal and distal centrioles were located within the nuclear notch and arranged orthogonal to each other. The axoneme had a typical 9 + 2 microtubule structure. The flagellar length of spermatozoon was 66.94 ± 0.46 µm. Spermatozoa were immotile in the seminal plasma. Dilution of sperm with natural seawater (1100 mOsmol/kg) resulted in initiation of motility for 91.0 ± 3.4% of spermatozoa with average velocity of 86.2 ± 2.3 µm/s and beating frequency of 52 Hz. The duration of spermatozoa motility was > 6 min; however, the percentage of motile spermatozoa decreased at 60 s post-activation. When osmolality of natural seawater was modified using distilled water or NaCl, spermatozoa motility was not initiated at ≤ 400 and ≥ 2500 mOsmol/kg, and the highest percentage of motility was observed at 730-1580 mOsmol/kg. In a sucrose solution, spermatozoa motility was initiated and suppressed at 600 and 1500 mOsmol/kg, respectively, and highest percentage of motility was observed at 800-1100 mOsmol/kg. Spermatozoon morphology comparisons within Gadiformes showed differences in dimensions of head and mitochondria, flagellar length, and number of mitochondria. The present study provides valuable data that can be used for phylogenetic implications based on spermatozoon morphology and for development of artificial fertilization and sperm cryopreservation protocols based on sperm motility.


Assuntos
Gadus morhua/fisiologia , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/ultraestrutura , Animais , Masculino , Concentração Osmolar , Espermatozoides/fisiologia
5.
J Cardiothorac Surg ; 15(1): 234, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32873336

RESUMO

BACKGROUND: Recent studies show that substantial percentage of patients experienced worsening of health related quality of life (HRQoL) 1 year after cardiac surgery. The aim of this study is to identify risk factors that interfere with improvement of HRQoL. METHODS: From December 2015 till July 2017 a prospective single centre observational study was carried out in 1920 patients participated who underwent non-salvage cardiac surgery. All patients were requested to complete a Short Form 36 (SF-36) questionnaire before and 1 year after surgery. Primary aim of the study was to identify risk factors for non-recovery in the physical domain of the SF-36 in all cardiac surgery patients. Secondary aim was to identify identical risk factors in patients with isolated coronary artery bypass grafting. RESULTS: After cardiac surgery, the questionnaires for physical and mental health were completed by respectively 803 and 807 patients. Median age was 69[62-75] years, and 77% was male. In comparison to the preoperative status, 176 patients (21.9%) did not display an improvement in the SF-36 physical domain score 1 year after cardiac surgery. In a multivariate analysis independent risk factors for non-recovery in the SF-36 physical domain were baseline SF36 physical domain score (OR 0.954[0.942-0.965], P < 0.001), diabetes (OR 0.437 [0.265-0.720], P 0.001), female sex (OR 0.492 [0.307-0.789], P 0.003), post-operative infection (OR 0.240 [0.109-0.525], P < 0.001) and PCI within 1 year (OR 0.113 [0.036-0.349], P < 0.001) For isolated CABG, 23.2% of patients did not display an improvement in the physical domain score and risk factors appeared to be identical. CONCLUSIONS: Twenty two percent of all cardiac surgery patients did not show an improvement in the physical domain score of the HRQoL between the preoperative period and 1 year after surgery. Independent risk factors for non-recovery after cardiac surgery were baseline SF-36 physical domain score, diabetes, female sex, any postoperative infection and the need for PCI in the first year. Further research is needed to tailor the patient selection procedure prior to surgery and potentially modify risk factors in the perioperative process. TRIAL REGISTRATION: Due to type of study not applicable. https://www.ccmo.nl/metcs/erkende-metcs/regionale-toetsingscommissie-patientgebonden-onderzoek .


Assuntos
Procedimentos Cirúrgicos Cardíacos , Qualidade de Vida , Idoso , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Ponte de Artéria Coronária , Complicações do Diabetes/complicações , Feminino , Nível de Saúde , Humanos , Infecções/etiologia , Masculino , Pessoa de Meia-Idade , Intervenção Coronária Percutânea , Desempenho Físico Funcional , Complicações Pós-Operatórias/etiologia , Período Pós-Operatório , Período Pré-Operatório , Estudos Prospectivos , Fatores de Risco , Fatores Sexuais , Inquéritos e Questionários , Fatores de Tempo
6.
Eur Heart J Case Rep ; 4(3): 1-5, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32617493

RESUMO

BACKGROUND: Anomalous left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital disorder resulting in ischaemia and myocardial infarction which can act as a potential substrate for life-threatening arrhythmias and sudden cardiac death. CASE SUMMARY: A 19-year-old man was admitted to the hospital after successful resuscitation from an out-of-hospital cardiac arrest (OHCA) due to ventricular fibrillation occurring during jogging. In the diagnostic work-up of the OHCA, computed tomography identified an ALCAPA. The patient was referred to our tertiary hospital for surgical correction. Direct reimplantation of the left coronary artery in the aorta was performed. During follow-up, 24-h electrocardiogram revealed short episodes of non-sustained ventricular tachycardia (VT). The magnetic resonance imaging at initial admission showed focal wall thinning and transmural late gadolinium enhancement consistent with a previous anterolateral myocardial infarction. Therefore, the aetiology of the OHCA could be due to a scar-related mechanism and not necessarily due to a reversible cause and an implantable cardioverter-defibrillator (ICD) was considered indicated. Given the young age and the lower complication rates, a subcutaneous device was preferred over a transvenous ICD. However, as a subcutaneous ICD (S-ICD) lacks the possibility of anti-tachycardia pacing, programmed electrical stimulation (PES) was performed to test for inducibility of monomorphic, re-entrant VT. After a negative PES, an S-ICD was implanted. DISCUSSION: ALCAPA is a potential cause of OHCA in young patients. Some of these patients keep an irreversible substrate for ventricular arrhythmias despite full surgical revascularization and might be candidates for (subcutaneous) ICD implantation.

7.
Theriogenology ; 136: 143-165, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31265944

RESUMO

Fish spermatozoa acquire potential for motility in the sperm duct where they are immotile. Osmolality of the seminal plasma is a key factor to maintain spermatozoa in the quiescent state in either freshwater or marine fishes. However, potassium (K+) ions prevent spermatozoa motility in salmonid and sturgeon fishes, while CO2 inhibits spermatozoa motility in flatfishes. Once, spermatozoa are released at spawning, their motility is initiated in hypo-osmotic and hyper-osmotic environments in freshwater and marine fishes, respectively. Some substances produced by the testes (a progestin), or released from oocytes (peptides) induce spermatozoa hypermotility in some marine fishes including the Atlantic croaker and Pacific herrings, respectively. Duration of spermatozoa motility is short, lasting for a few seconds to few minutes in most fishes due to rapid depletion of energy required for the beating of the motility apparatus called axoneme. In the osmotic-activated spermatozoa, K+ and water effluxes occur in freshwater and marine fishes, respectively, which trigger spermatozoa motility signaling. In general, initiation of axonemal beating is associated with an increase in intracellular calcium (Ca2+) ions in spermatozoa of both freshwater and marine fishes and a post- or pre-increase in intracellular pH, while cyclic adenosine monophosphate (cAMP) remains unchanged. However, axonemal beating is cAMP-dependent in demembranated spermatozoa of salmonid and sturgeon fishes. Calcium from extracellular environment or intracellular stores supply required Ca2+ concentration for axonemal beating. Several axonemal proteins have been so far identified in fishes that are activated by Ca2+ and cAMP, directly or mediated by protein kinase C and protein kinase A, respectively. The present study reviews differences and similarities in complex regulatory signals controlling spermatozoa motility initiation in fishes, and notes physiological mechanisms that await elucidation.


Assuntos
Peixes/fisiologia , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/fisiologia , Animais , Masculino , Transdução de Sinais/fisiologia , Especificidade da Espécie
8.
FEBS Lett ; 593(14): 1735-1750, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31115913

RESUMO

During spermatogenesis, fatty acids play an important role both as structural components and messengers that trigger male germ cell line differentiation. The spontaneous oxidation of fatty acids causes a decrease in mammalian fertility. Here, we examine the effects of nonenzymatically oxidized arachidonic acid (AAox ) on mouse spermatogenic T-type Ca2+ currents (ICaT ) due to their physiological relevance during spermatogenesis. AAox is 25-fold more potent than AA at inhibiting ICaT and it left shifts the I-V curve peak and both activation and steady-state inactivation curves. In addition, ICaT deactivation kinetics and their recovery from inactivation are slower in the presence of AAox . Therefore, the fraction of inactivated Ca2+ channels is increased. AAox -induced ICaT inhibition could contribute to male infertility affecting Ca2+ regulation in spermatogenic cells.


Assuntos
Ácido Araquidônico/metabolismo , Canais de Cálcio Tipo T/metabolismo , Espermatogênese , Animais , Linhagem Celular , Fenômenos Eletrofisiológicos , Ativação do Canal Iônico , Cinética , Masculino , Camundongos , Oxirredução , Espermatozoides/citologia , Espermatozoides/metabolismo
9.
Theriogenology ; 97: 134-138, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28583596

RESUMO

The morphology of the reproductive system of acipenseriform fishes is quite different from that of teleostean species, but an associated unique physiological difference in male sturgeons was not discovered until recently; sperm of sturgeons passes through the kidneys then via Wolffian ducts into the environment rather that emptying directly through seminal ducts. The mixing of sperm with excretory products has been found to be a requisite for the capacity to be activated (maturation step) instead of being deleterious. In the current review we summarize results of studies performed in our laboratory on physiological processes involved in sturgeon sperm maturation, namely changes in: 1) ionic environment; 2) sensitivity of spermatozoa to calcium ions (Ca2+); 3) antioxidant enzymes and proteolytic activities; and 4) content in macroergic phosphates arising during this maturation process. We also discuss taxa-specific aspects of sturgeon sperm maturation in relation to hormonal regulation of spermiation, and the unusual features of sturgeon sperm maturation relative to using testicular sturgeon sperm in aquaculture.


Assuntos
Peixes/fisiologia , Maturação do Esperma/fisiologia , Espermatozoides/fisiologia , Animais , Genitália Masculina/anatomia & histologia , Genitália Masculina/fisiologia , Masculino
10.
Reprod Fertil Dev ; 29(7): 1319-1328, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27246727

RESUMO

The role of Ca2+ in sturgeon sperm maturation and motility was investigated. Sperm from mature male sterlets (Acipenser ruthenus) were collected from the Wolffian duct and testis 24h after hormone induction. Testicular spermatozoa (TS) were incubated in Wolffian duct seminal fluid (WDSF) for 5min at 20°C and were designated 'TS after IVM' (TSM). Sperm motility was activated in media with different ion compositions, with motility parameters analysed from standard video microscopy records. To investigate the role of calcium transport in the IVM process, IVM was performed (5min at 20°C) in the presence of 2mM EGTA, 100µM Verapamil or 100µM Tetracaine. No motility was observed in the case of TS (10mM Tris, 25mM NaCl, 50mM Sucr with or without the addition of 2mM EGTA). Both incubation of TS in WDSF and supplementation of the activation medium with Ca2+ led to sperm motility. The minimal Ca2+ concentration required for motility activation of Wolffian duct spermatozoa, TS and TSM was determined (1-2nM for Wolffian duct spermatozoa and TSM; approximately 0.6mM for TS). Motility was obtained after the addition of verapamil to the incubation medium during IVM, whereas the addition of EGTA completely suppressed motility, implying Ca2+ involvement in sturgeon sperm maturation. Further studies into the roles of Ca2+ transport in sturgeon sperm maturation and motility are required.


Assuntos
Cálcio/metabolismo , Peixes/metabolismo , Espermatozoides/metabolismo , Animais , Cálcio/farmacologia , Bloqueadores dos Canais de Cálcio/farmacologia , Meios de Cultura , Técnicas In Vitro , Transporte de Íons , Masculino , Sêmen/metabolismo , Maturação do Esperma/efeitos dos fármacos , Maturação do Esperma/fisiologia , Motilidade dos Espermatozoides/efeitos dos fármacos , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/efeitos dos fármacos , Testículo/citologia , Verapamil/farmacologia , Ductos Mesonéfricos/metabolismo
11.
Theriogenology ; 84(1): 51-61, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25794841

RESUMO

In the present study, for the first time in fish spermatozoa, we describe the precise chronology of motility initiation of sterlet (sturgeon) sperm from completely immotile flagella to regular full wave propagation. The successive activation steps were investigated by high-speed video microscopy, using specific experimental situation, where sperm motility initiation was delayed in time up to several seconds (10 ± 2.68 seconds). Starting from fully immotile, the flagellum shows some trembling for a brief period, soon followed by appearance of the first real bend (so-called "principal bend") with a large wave amplitude 4.28 ± 0.65 µm, then by the "reverse bend," the latter presenting a lower (P < 0.05) wave amplitude (1.14 ± 0.32 µm). This couple of first bends formed at the basal region begins to propagate toward the flagellar tip but gradually fades when reaching the midflagellum, wherein consequently the sperm cell remains nonprogressive. This behavior repeats several times until a stage where the amplitude of the reverse bend gradually reaches a value similar that of the principal bend: The larger amplitude of this couple of bends finally leads to sustain a real "takeoff" of the sperm cell characterized by a full flagellar wave propagation generating an active forward displacement similar to that occurring during regular steady state motility (several seconds after activation). Starting from the earliest stages of motility initiation, the wave propagation along the flagellum and formation of new waves proceeded in a helical manner leading to a 3-dimensional rotation of the whole spermatozoon. Eventually, we estimated that the time period needed from the activation signal (contact with fresh water) to full wave propagation ranges from 0.4 to 1.2 seconds.


Assuntos
Peixes/fisiologia , Motilidade dos Espermatozoides , Espermatozoides/fisiologia , Animais , Aquicultura , Flagelos/fisiologia , Masculino , Espermatozoides/citologia
12.
Reprod Biol ; 14(2): 160-3, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24856476

RESUMO

The aim of the study was to examine sperm maturation in sturgeon and to establish the localization of the maturation. We demonstrated that sperm maturation occurs in sturgeon outside the testes via dilution of sperm by urine. The process involves the participation of high molecular weight (>10kDa) substances and calcium ions.


Assuntos
Peixes/fisiologia , Maturação do Esperma/fisiologia , Motilidade dos Espermatozoides/fisiologia , Animais , Masculino
13.
Fish Physiol Biochem ; 40(5): 1417-21, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24718964

RESUMO

The role of environmental ion composition and osmolality in Ca(2+) signaled activation was assessed in spermatozoa of brook trout Salvelinus fontinalis. Milt from ten mature males was obtained by abdominal massage. Spermatozoa motility was evaluated in 0, 100, and 300 mOsm/kg NaCl or sucrose solutions, buffered by 10 mM Tris-HCl pH 8.5. For investigation of spermatozoa reaction to external Ca(2+) concentration, 2 mM ethylene glycol tetraacetic acid (EGTA) was added to the activation media as a calcium ions chelator. For investigation of the effect of external Na(+) concentration in conditions of low external Ca(2+), 100 µM amiloride was added to the EGTA-containing solutions as a Na(+) transport blocker. Low motility was observed in sucrose (Na(+) free) solutions containing 2 mM EGTA but not in Na(+) solutions containing 2 mM EGTA. Addition of amiloride led to significantly increased motility (P < 0.05) compared with sucrose (Na(+) free) solutions containing 2 mM EGTA. We conclude that Na(+) transport in Ca(2+)-free solutions plays a regulatory role in brook trout spermatozoa activation. The influence of competitive Na(+) and Ca(2+) transport on the control of spermatozoa activation requires further study with respect to its application for improvement of artificial activation and storage media.


Assuntos
Cálcio/metabolismo , Cloreto de Sódio/farmacologia , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/fisiologia , Sacarose/farmacologia , Truta/fisiologia , Amilorida , Análise de Variância , Animais , Transporte Biológico/fisiologia , Cálcio/farmacologia , Ácido Egtázico , Masculino , Cloreto de Sódio/metabolismo , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Estatísticas não Paramétricas , Sacarose/metabolismo
14.
Theriogenology ; 79(5): 872-81, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23394972

RESUMO

The aim of this study was to describe spermatozoa volume changes during the motility period of fish species with either osmotic (common carp Cyprinus carpio) or with ionic (sterlet Acipenseri ruthenus and brook trout Salvelinus fontinalis) modes of motility activation. Nephelometry, light microscopy, and spermatocrit methods were used for quantitative assessment of cell volume changes in media of different osmolalities. Significant correlation (R(2) = 0.7341; P < 0.001) between parameter of volume changes measured using nephelometry and light microscopy methods confirmed nephelometry as a sufficiently sensitive method to detect changes of spermatozoa volume. The spermatocrit alteration method resulted in a large proportion of damaged and potentially immotile spermatozoa in media of osmolality less than 150 mOsm/kg in carp and osmolalities from 10 to 300 mOsm/kg in sterlet and brook trout. Therefore, this method is not reliable for assessing spermatozoa swelling in hypotonic solutions, because the integrity of the cells is not fully preserved. Increase in carp spermatozoa (osmotic activation mode) volume occurred during the motility period in hypotonic conditions, but no indications of volume changes were found in sterlet and brook trout spermatozoa (ionic activation mode) associated with environmental osmolality alteration. Accordingly, we conclude that sperm volume changes are differentially involved in the motility activation process. Species-specific differences in spermatozoa volume changes as a response to a hypotonic environment during the motility period are discussed in relation to their potent physiological role.


Assuntos
Peixes/fisiologia , Motilidade dos Espermatozoides , Espermatozoides/fisiologia , Animais , Carpas/fisiologia , Masculino , Microscopia Eletrônica de Varredura , Nefelometria e Turbidimetria , Espermatozoides/ultraestrutura , Truta/fisiologia
15.
Cryobiology ; 66(2): 192-4, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23270681

RESUMO

Post-thaw motility rate, curvilinear velocity (VCL), and fertilizing ability of carp spermatozoa can be improved by short-term treatment with moderately hypotonic media prior to freezing. Before cryopreservation, carp sperm samples were treated with NaCl solutions of differing osmolalities, ranging from 100 to 300mOsmkg(-1) for 10s, after which final osmolality was adjusted to 300mOsmkg(-1). The resulting sperm suspension was diluted 1:1 with cryoprotective medium and frozen using conventional techniques. Control samples were treated in the same way, without the pre-dilution step. Post-thaw motility rate in samples pretreated with 200mOsmkg(1) NaCl was significantly higher (44±10%) than in controls (21±15%) and samples pretreated with 100mOsmkg(-1) (25±15%) and 300mOsmkg(-1) (25±12%) NaCl. Significantly higher mean VCL were observed in samples pretreated with 100, 150, and 200mOsmkg(-1) (119±24, 118±22, and 115±32µms(-1), respectively) compared to controls (92±27µms(-1)). Fertilization rate of frozen-thawed sperm treated with 200mOsmkg(-1) solution of 2M NaCl was significantly higher (25±18%) than that of sperm treated with 300mOsmkg(-1) NaCl solutions (12±7%) and the control (9±6%).


Assuntos
Carpas/fisiologia , Criopreservação/veterinária , Preservação do Sêmen/veterinária , Cloreto de Sódio/metabolismo , Espermatozoides/citologia , Animais , Criopreservação/métodos , Crioprotetores/metabolismo , Feminino , Fertilização , Soluções Hipotônicas , Masculino , Concentração Osmolar , Preservação do Sêmen/métodos , Motilidade dos Espermatozoides , Espermatozoides/metabolismo
16.
Eur Heart J Cardiovasc Imaging ; 13(12): 985-90, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23034989

RESUMO

In patients with chronic ischaemic left ventricular dysfunction, revascularization may lead to symptomatic and prognostic improvement. Cardiovascular magnetic resonance (CMR) imaging with its high spatial resolution provides the qualitative and quantitative, global and regional information on myocardial anatomy and function. In combination with a gadolinium-based contrast agent, CMR allows an accurate quantification of the myocardial scar and predicts the likelihood of functional recovery after revascularization. The aim of this review is to summarize our current understanding of the detection of myocardial viability using CMR, and why it may be the preferred technique in the assessment of patients with ischaemic cardiomyopathy.


Assuntos
Cardiomiopatias/fisiopatologia , Cardiomiopatias/cirurgia , Imageamento por Ressonância Magnética/métodos , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/cirurgia , Revascularização Miocárdica , Disfunção Ventricular Esquerda/diagnóstico , Disfunção Ventricular Esquerda/cirurgia , Doença Crônica , Meios de Contraste , Gadolínio DTPA , Humanos , Isquemia Miocárdica/fisiopatologia , Prognóstico , Recuperação de Função Fisiológica , Disfunção Ventricular Esquerda/fisiopatologia
17.
Nucl Med Commun ; 32(12): 1169-73, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22045477

RESUMO

OBJECTIVES: In patients with chronic ischemic myocardial dysfunction, perfusable tissue index (PTI) obtained with positron emission tomography using oxygen-15-labeled water and carbon monoxide as tracers is inversely related to the extent of myocardial scar (nonperfusable tissue). Delayed contrast-enhanced (DCE) magnetic resonance imaging (MRI) accurately depicts the regional extent of myocardial fibrosis and predicts functional recovery after revascularization in patients with ischemic cardiomyopathy. Our aim was to compare PTI as a viability marker with DCE MRI. METHODS: Fourteen patients with ischemic left ventricular dysfunction were studied with positron emission tomography, using oxygen-15-labeled water and carbon monoxide as tracers, and with contrast-enhanced MRI. RESULTS: Functional improvement occurred in 38 of initially dysfunctional, revascularized segments (56%). Mean PTI was 1.04 ± 0.20 in the improved segments versus 0.85 ± 0.21 in the group without functional improvement (P<0.001). The areas under the receiver operator characteristics curves of PTI and DCE MRI were 0.7 and 0.74, respectively (P=not significant). Cutoff value of 25% DCE allowed correct identification of 82% segments with reversible dysfunction and 64% segments without reversible dysfunction. A threshold of 0.89 for PTI yielded the best diagnostic accuracy with sensitivity and specificity values of 76 and 54%, respectively. CONCLUSION: PTI can identify viable myocardium and predict improvement in regional function after revascularization in patients with chronic ischemic left ventricular dysfunction. Its diagnostic accuracy is comparable with that of DCE MRI.


Assuntos
Imageamento por Ressonância Magnética/métodos , Isquemia Miocárdica/diagnóstico por imagem , Imagem de Perfusão do Miocárdio/métodos , Tomografia por Emissão de Pósitrons/métodos , Ventriculografia com Radionuclídeos/métodos , Disfunção Ventricular Esquerda/diagnóstico por imagem , Idoso , Antimetabólitos , Monóxido de Carbono , Doença Crônica , Meios de Contraste , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/fisiopatologia , Isquemia Miocárdica/cirurgia , Revascularização Miocárdica , Radioisótopos de Oxigênio , Prognóstico , Recuperação de Função Fisiológica , Sensibilidade e Especificidade , Disfunção Ventricular Esquerda/cirurgia , Função Ventricular Esquerda/fisiologia
18.
J Cardiovasc Magn Reson ; 11: 6, 2009 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-19272147

RESUMO

BACKGROUND: Quantification of late gadolinium enhanced cardiovascular magnetic resonance (LGE CMR) by objective window setting increases reproducibility and facilitates multicenter comparison and cooperation. So far, quantification methods or models have only been validated to postmortem animal studies. This study was undertaken to evaluate quantification of LGE in relation to the clinical standard of viability, i.e. functional outcome after revascularization.Thirty-eight patients with chronic ischemic myocardial dysfunction underwent cine and LGE 1 month before and cine CMR 6 months after coronary revascularization. Enhancement was quantified by thresholding window setting at: 2-8 SD above mean signal intensity of a remote normal region, and according to the full width at half maximum method (FWHM). Dysfunctional segments were divided in 5 groups according to segmental extent of enhancement (SEE): SEE 1--no enhancement to SEE 5--76-100% with each quantification method. RESULTS: Quantification methods had a strong influence on SEE and total infarct size. Multilevel analysis showed that thresholding contrast images at 6 SD best predicted segmental functional outcome after revascularization, but the difference with other methods was small and non-significant. CONCLUSION: Simple thresholding techniques strongly influence global and segmental extent of LGE, but have relatively little influence on the accuracy to predict segmental functional improvement after revascularization.


Assuntos
Gadolínio DTPA , Isquemia Miocárdica/fisiopatologia , Doença Crônica , Comorbidade , Meios de Contraste , Feminino , Humanos , Aumento da Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/diagnóstico , Curva ROC
19.
Eur Heart J ; 29(16): 2000-5, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18556713

RESUMO

AIMS: We sought to evaluate the relation between long-term functional outcome after revascularization in patients with chronic ischaemic left ventricular (LV) dysfunction and baseline extent of myocardial fibrosis. METHODS AND RESULTS: Thirty-five patients underwent cine and delayed contrast-enhanced cardiovascular magnetic resonance (deCMR) for the quantitative assessment of regional and global LV functions and segmental extent of hyperenhancement (SEH). Function was assessed 1 month before and 3, 6, and 24 +/- 12 months after revascularization, and temporal changes were related to baseline extent of hyperenhancement. The likelihood of functional improvement was inversely related to the SEH during the entire follow-up: at the end of the study period, segments with 1-25, 26-50, 51-75, and 76-100% SEH were 2, 5, 11, and 86 times, respectively, less likely to have functional improvement than segments without hyperenhancement (multilevel analysis, P < 0.001). Although improvement continued over the whole study period in all SEH groups, the time course was significantly more delayed in segments with more extensive hyperenhancement at baseline (multilevel analysis, P < 0.001). CONCLUSION: In patients with chronic ischaemic LV dysfunction, improvement of dysfunctional but viable myocardium can be considerably delayed. Both the likelihood and the time course of long-term functional improvement are related to the baseline amount of scar, as visualized by deCMR.


Assuntos
Meios de Contraste , Gadolínio DTPA , Imageamento por Ressonância Magnética/métodos , Revascularização Miocárdica/normas , Miocárdio Atordoado/cirurgia , Disfunção Ventricular Esquerda/diagnóstico , Doença Crônica , Cicatriz/diagnóstico , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Pessoa de Meia-Idade , Recuperação de Função Fisiológica/fisiologia , Fatores de Tempo , Resultado do Tratamento , Disfunção Ventricular Esquerda/fisiopatologia , Disfunção Ventricular Esquerda/cirurgia
20.
J Cardiovasc Magn Reson ; 9(5): 815-21, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17891620

RESUMO

In patients with chronic ischemic myocardial dysfunction, late gadolinium enhancement CMR (LGE-CMR) accurately depicts the regional extent of fibrosis and predicts functional recovery after revascularization. We hypothesized that the predictive accuracy of LGE-CMR could be optimized by not only taking into account the transmural extent of hyperenhancement but also the amount of residual, non-enhanced viable myocardium, and procedure related necrosis. We studied 45 patients with chronic ischemic left ventricular dysfunction, who underwent cine and LGE-CMR 1 month before and 3 months after surgical or percutaneous revascularization. Segmental and global function, scar, presence of a significant residual viable rim (defined as >or=4.5 mm), and procedure related necrosis were fully quantified using standardized methods and objective thresholds. Sixty percent of segments without hyperenhancement showed functional improvement at follow-up. No improvement was observed in segments with >75% segmental extent of hyperenhancement (SEH), while segments with 1-25%, 26-50%, and 51-75% SEH were 4, 8, and 20 times less likely to improve (multilevel analysis, p<0.001). Thickness of the viable rim largely paralleled total wall thickness; therefore, the presence of a significant viable rim did not provide additional diagnostic value beyond SEH. Procedure related necrosis was found in 12 (27%) patients. The presence of procedure related necrosis was the only (negative) predictor of changes in left ventricular volumes and ejection fraction. In conclusion, we found that functional outcome after revascularization was influenced by both transmural extent of hyperenhancement and procedure related necrosis. However, the presence of a significant residual, viable rim was of no additional diagnostic value.


Assuntos
Meios de Contraste , Gadolínio DTPA , Imagem Cinética por Ressonância Magnética , Imageamento por Ressonância Magnética , Isquemia Miocárdica/diagnóstico , Miocárdio/patologia , Idoso , Doença Crônica , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/patologia , Isquemia Miocárdica/fisiopatologia , Isquemia Miocárdica/terapia , Necrose , Valor Preditivo dos Testes , Recuperação de Função Fisiológica , Projetos de Pesquisa , Volume Sistólico , Fatores de Tempo , Resultado do Tratamento , Função Ventricular Esquerda
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