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Olfactory abilities to discriminate conspecifics can be determinant to prevent hybridization between closely-related species in many taxa. Annual killifish Austrolebias reicherti and A. charrua are sister species inhabiting temporary ponds within Eastern Wetlands of Uruguay with an overlapping area in their distributions. Herein, we assess species recognition sensory abilities in females of A. reicherti in classic dual-choice tests. We exposed two different groups of females, one to olfactory but not visual cues, and the other to visual but not olfactory cues, from conspecific and heterospecific A. charrua males. Austrolebias reicherti females preferred conspecific males when based solely on olfactory cues, and showed no discrimination when exposed to visual traits only. Austrolebias inhabit shallow, muddy and highly turbid ponds that may promote the use of non-visual cues. Although preliminary, the results of this study suggest the importance of chemical communication in species mate recognition in A. reicherti and points annual fishes as a promising model to study the role of mate choice in reproductive isolation and speciation.

Background: Paravalvular regurgitation (paravalvular leak) is a serious and rare complication associated with valve replacement surgery. Studies have shown a 3% to 6% incidence of paravalvular regurgitation with hemodynamic repercussion. Few studies have compared surgical and percutaneous approaches for repair. Objectives: To compare the surgical and percutaneous approaches for paravalvular regurgitation repair regarding clinical outcomes during hospitalization and one year after the procedure. Methods: This is a retrospective, descriptive and observational study that included 35 patients with paravalvular leak, requiring repair, and followed up at the Dante Pazzanese Institute of Cardiology between January 2011 and December 2013. Patients were divided into groups according to the established treatment and followed up for 1 year after the procedure. Results: The group submitted to percutaneous treatment was considered to be at higher risk for complications because of the older age of patients, higher prevalence of diabetes, greater number of previous valve surgeries and lower mean creatinine clearance value. During hospitalization, both groups had a large number of complications (74.3% of cases), with no statistical difference in the analyzed outcomes. After 1 year, the percutaneous group had a greater number of re-interventions (8.7% vs 20%, p = 0.57) and a higher mortality rate (0% vs. 20%, p = 0.08). A high incidence of residual mitral leak was observed after the percutaneous procedure (8.7% vs. 50%, p = 0.08). Conclusion: Surgery is the treatment of choice for paravalvular regurgitation. The percutaneous approach can be an alternative for patients at high surgical risk.

The intensity of mating competition and the potential benefits for female of mating with certain males can be influenced by several extrinsic factors, such that behavioral decisions can be highly context-dependent. Short-lived species with a single reproductive season are a unique model to study context-sensitive mating decisions. Through exhaustive sampling in the field and simultaneous choice tests in the laboratory, we evaluated operational sex ratio (OSR) and female mate choice at the beginning and end of the reproductive season in the annual killifish Austrolebias reicherti. We found seasonal change in both OSR and female mate choice. At the start of the reproductive season the OSR did not deviate from parity, and females preferred larger males. Later in the reproductive season, while the proportion of males in the ponds decreased, females became unselective with respect to male size. The particular biological cycle of annual killifish, where both life expectancy and mating opportunities decline sharply over a short timescale, could account for the seasonal change in female choice. Reduction in choosiness could arise from diminished reproductive prospects due to a decline in male availability. Moreover, as the end of the season approaches, any benefits of choosiness are presumably reduced: a female's fitness will be higher if she mates with any male than if she forgoes reproduction and dies. Future work will disentangle the mechanisms underlying seasonal changes in mating preferences, notably direct responses to demographic factors, environmental cues, or intrinsic changes during development.

FUNDAMENTO: Na síndrome coronariana aguda (SCA), a hiperglicemia, à admissão hospitalar, está associada à presença de eventos adversos cardiovasculares em pacientes com ou sem diabetes. OBJETIVO: Avaliar o valor prognóstico da hiperglicemia de estresse na evolução intra-hospitalar de pacientes admitidos por SCA. MÉTODOS: Foram incluídos 152 pacientes admitidos, entre setembro de 2005 e fevereiro de 2010, em unidade de dor torácica de hospital terciário com diagnóstico de SCA, que apresentavam valor da glicemia laboratorial na admissão. O grupo I foi formado pelos pacientes com hiperglicemia de estresse, definida por glicemia na admissão > 126 mg/dL em não diabéticos e > 200 mg/dL nos diabéticos, e o grupo II pelos pacientes com níveis glicêmicos inferiores aos níveis estabelecidos. Analisou-se a associação da hiperglicemia e evolução intra-hospitalar. RESULTADOS: A hiperglicemia de estresse associou-se a complicações intra-hospitalares, aumento da idade e gênero feminino. Na análise multivariada, apenas gênero feminino (OR = 2,04; IC95% 1,03 - 4,06, p = 0,007) e complicações intra-hospitalares (OR = 3,65; IC95% 1,62 - 8,19, p = 0,002) se associaram de forma independente à hiperglicemia na admissão. CONCLUSÃO: A hiperglicemia de estresse é fator preditivo independente para complicações intra-hospitalares após SCA em pacientes diabéticos ou não. Os resultados alertam para a necessidade de avaliarmos a glicemia na admissão em todos os pacientes admitidos por SCA, incluindo os não diabéticos, com o intuito de identificarmos os indivíduos com maior risco de complicações. _________________________________________________________________________________________ ABSTRACT: BACKGROUND: In acute coronary syndrome (ACS), admission hyperglycemia is associated with adverse cardiovascular events in diabetic and nondiabetic patients. OBJECTIVE: To assess the prognostic value of stress hyperglycemia for the in-hospital outcome of patients admitted due to ACS. METHODS: This study included 152 patients admitted to the chest pain unit of a tertiary hospital diagnosed with ACS, who had admission blood glucose data, from September 2005 to February 2010. Group I comprised patients with stress hyperglycemia, defined as admission blood glucose concentration > 126 mg/dL for nondiabetic individuals and admission blood glucose concentration > 200 mg/dL for diabetic individuals. Group II was formed by patients with admission blood glucose concentration lower than those established. The association of hyperglycemia and in-hospital outcome was assessed. RESULTS: Stress hyperglycemia associated with in-hospital complications, age increase and female sex. On multivariate analysis, only female sex (OR = 2.04; 95% CI: 1.03 - 4.06; p = 0.007) and in-hospital complications (OR = 3.65; 95% CI: 1.62 - 8.19; p = 0.002) associated independently with admission hyperglycemia. CONCLUSIONS: Stress hyperglycemia is an independent predictive factor for in-hospital complications after ACS in diabetic and nondiabetic patients. The results highlight the need to assess admission blood glucose concentration in all patients admitted due to ACS, including nondiabetic ones, aiming at identifying those at higher risk for complications.

Since many traits are involved in both female mating decisions and male contest outcomes, female mate choice and male competition can act in concert to intensify sexual selection on male traits, or in opposition to weaken it. In the sexually dimorphic annual killifish, Austrolebias charrua, we evaluated the effect of male body size on female mate choice, male-male competition, and their interaction. We carried out an experiment with three consecutive stages: (i) female choice test between males of different size in a classic two-choice device, (ii) agonistic interactions between males used in the previous stage, and (iii) a second female choice test to evaluate preference consistency in females that either were allowed or were prevented from observing the male competition. Larger males were preferred by females and became socially dominant in agonistic interactions. Further, females were consistent in their choices, and this consistency was independent of whether they had observed or not the male contest. Our research shows that, in A. charrua, intrasexual competition and female mate choice act in concert with respect to male body size. The unique life-history of Austrolebias and the high repeatability of mate-choice assays make this system a promising candidate for studies of behavioural evolution.

To evaluate the clinical efficacy and safety of subcutaneous (SC) low molecular weight heparin (LMWH) compared to intravenous (IV) non fractioned heparin (NFH) in unstable angina, acute myocardial infarction and post-percutaneous transluminal coronary angioplasty.From September/92 to April/94, 314 patients were randomized in two groups. Group I-- 154 patients treated with SC LMWH, using in the 1st phase SC LMWH with a dosage of 160 UaXa IC/kg/day (group IA--92 patients), and in the 2nd, a dosage of 320 UaXa IC/kg/day (group IB--62 patients). Group II--160 patients treated with IV NFH 100UI/kg (bolus), followed by 1000UI/h with adjusted dosage by activated partial thromboplastin time.There was not a statistically significant difference among the three groups in relation to cardiac events, hemorrhagic complications and deaths.The clinical efficacy and safety of SC LMWH in patients with unstable angina, acute myocardial infarction and post-percutaneous transluminal coronary angioplasty were similar to IV NFH with the dosages used in this study.

To describe the use of myocardial reperfusion strategies (percutaneous transluminal coronary angioplasty-PTCA and intravenous trombolysis) whenever it is possible to use emergency cinecoronariography in acute myocardial infarction (AMI).The records of patients admitted with initial diagnosis of AMI, until six hours after the beginning of symptoms, were reviewed retrospectively, between March/92 and December/93.One hundred forty-three patients were admitted with suspected AMI. Eighty-one (57%) presented definitive criteria for this diagnosis. Fifty-two patients (64%) were admitted in the first six hours from the beginning of symptoms. Thirty-eight (73%) were male and the mean age was 59 +/- 12 years. Cinecoronariography was indicated immediately in 36 of 52 (69%) patients, with purpose to use PTCA. That was done in 30 (58%). Two (4%) patients were submitted to emergency surgical myocardial revascularization. Intravenous thrombolysis was used in 11 (21%) patients. At admission, the conservative treatment was chosen for five out of nine left patients, based on clinical grounds.The availability of emergency cinecoronariography made an early reperfusion strategy possible in 83% of patients admitted with AMI in the first six hours after the beginning of symptoms.