Reduced genetic diversity and the success of the invasive peacock bass (Cichliformes: Cichlidae)

Abstract Several species of Cichla successfully colonized lakes and reservoirs of Brazil, since the 1960s, causing serious damage to local wildlife. In this study, 135 peacock bass were collected in a reservoir complex in order to identify if they represented a single dominant species or multiple ones, as several Cichla species have been reported in the basin. Specimens were identified by color pattern, morphometric and meristic data, and using mitochondrial markers COI, 16S rDNA and Control Region (CR). Overlapping morphological data and similar coloration patterns prevented their identification using the taxonomic keys to species identification available in the literature. However, Bayesian and maximum likelihood from sequencing data demonstrated the occurrence of a single species, Cichla kelberi. A single haplotype was observed for the 16S and CR, while three were detected for COI, with a dominant haplotype present in 98.5% of the samples. The extreme low diversity of the transplanted C. kelberi evidenced a limited number of founding maternal lineages. The success of this colonization seems to rely mainly on abiotic factors, such as increased water transparency of lentic environments that favor visual predators that along with the absence of predators, have made C. kelberi a successful invader of these reservoirs.

Resumo Muitas espécies de Cichla colonizaram com sucesso lagos e reservatórios do Brasil desde os anos 1960, causando graves prejuízos à vida selvagem nesses locais. Neste estudo, 135 tucunarés foram coletados em um complexo de reservatórios a fim de identificar se representavam uma espécie dominante ou múltiplas espécies, uma vez que diversas espécies de Cichla foram registradas na bacia. Os espécimes foram identificados com base na coloração, dados morfométricos e merísticos, e por marcadores mitocondriais COI, 16S rDNA e Região Controle (RC). A sobreposição dos dados morfométricos e o padrão similar de coloração impediram a identificação utilizando as chaves de identificação disponíveis na literatura. Entretanto, as análises bayesiana e de máxima verossimilhança de dados moleculares demonstraram a ocorrência de uma única espécie, Cichla kelberi. Um único haplótipo foi observado para o 16S e RC, enquanto três foram detectados para o COI, com um haplótipo dominante presente em 98,5% das amostras. A baixa diversidade nos exemplares introduzidos de C. kelberi evidenciou um número limitado de linhagens maternas fundadoras. O sucesso da invasão parece depender de fatores abióticos, como a maior transparência da água de ambientes lênticos que favorece predadores visuais que, atrelado à ausência de predadores, fez do C. kelberi um invasor bem-sucedido nesses reservatórios.

Reduced genetic diversity and the success of the invasive peacock bass (Cichliformes: Cichlidae) / Diversidade genética reduzida e o sucesso da espécie invasora tucunaré (Cichliformes: Cichlidae)

Abstract Several species of Cichla successfully colonized lakes and reservoirs of Brazil, since the 1960's, causing serious damage to local wildlife. In this study, 135 peacock bass were collected in a reservoir complex in order to identify if they represented a single dominant species or multiple ones, as several Cichla species have been reported in the basin. Specimens were identified by color pattern, morphometric and meristic data, and using mitochondrial markers COI, 16S rDNA and Control Region (CR). Overlapping morphological data and similar coloration patterns prevented their identification using the taxonomic keys to species identification available in the literature. However, Bayesian and maximum likelihood from sequencing data demonstrated the occurrence of a single species, Cichla kelberi. A single haplotype was observed for the 16S and CR, while three were detected for COI, with a dominant haplotype present in 98.5% of the samples. The extreme low diversity of the transplanted C. kelberi evidenced a limited number of founding maternal lineages. The success of this colonization seems to rely mainly on abiotic factors, such as increased water transparency of lentic environments that favor visual predators that along with the absence of predators, have made C. kelberi a successful invader of these reservoirs.

Resumo Muitas espécies de Cichla colonizaram com sucesso lagos e reservatórios do Brasil desde os anos 1960, causando graves prejuízos à vida selvagem nesses locais. Neste estudo, 135 tucunarés foram coletados em um complexo de reservatórios a fim de identificar se representavam uma espécie dominante ou múltiplas espécies, uma vez que diversas espécies de Cichla foram registradas na bacia. Os espécimes foram identificados com base na coloração, dados morfométricos e merísticos, e por marcadores mitocondriais COI, 16S rDNA e Região Controle (RC). A sobreposição dos dados morfométricos e o padrão similar de coloração impediram a identificação utilizando as chaves de identificação disponíveis na literatura. Entretanto, as análises bayesiana e de máxima verossimilhança de dados moleculares demonstraram a ocorrência de uma única espécie, Cichla kelberi. Um único haplótipo foi observado para o 16S e RC, enquanto três foram detectados para o COI, com um haplótipo dominante presente em 98,5% das amostras. A baixa diversidade nos exemplares introduzidos de C. kelberi evidenciou um número limitado de linhagens maternas fundadoras. O sucesso da invasão parece depender de fatores abióticos, como a maior transparência da água de ambientes lênticos que favorece predadores visuais que, atrelado à ausência de predadores, fez do C. kelberi um invasor bem-sucedido nesses reservatórios.

Reduced genetic diversity and the success of the invasive peacock bass (Cichliformes: Cichlidae).

Several species of Cichla successfully colonized lakes and reservoirs of Brazil, since the 1960's, causing serious damage to local wildlife. In this study, 135 peacock bass were collected in a reservoir complex in order to identify if they represented a single dominant species or multiple ones, as several Cichla species have been reported in the basin. Specimens were identified by color pattern, morphometric and meristic data, and using mitochondrial markers COI, 16S rDNA and Control Region (CR). Overlapping morphological data and similar coloration patterns prevented their identification using the taxonomic keys to species identification available in the literature. However, Bayesian and maximum likelihood from sequencing data demonstrated the occurrence of a single species, Cichla kelberi. A single haplotype was observed for the 16S and CR, while three were detected for COI, with a dominant haplotype present in 98.5% of the samples. The extreme low diversity of the transplanted C. kelberi evidenced a limited number of founding maternal lineages. The success of this colonization seems to rely mainly on abiotic factors, such as increased water transparency of lentic environments that favor visual predators that along with the absence of predators, have made C. kelberi a successful invader of these reservoirs.

Effect of extraction temperature on rheological behavior and antioxidant capacity of flaxseed gum.

Soluble flaxseed gum (SFG) extracted at different temperatures (25, 40, and 60 °C) was analyzed in relation to the yield, polysaccharides and phenolics composition, surface charge, color, and rheological properties. The yield of SFG extract increased as the extraction temperature increased. The SFG xylan was the main component regardless the extraction temperature, but a reduction of substituents on the xylose chain was observed when increasing the extraction temperature. The phenolic compounds were also affected by the extraction temperature, influencing the antioxidant capacity of the gum. For all the extraction temperatures, SFG aqueous solutions showed a shear time-independent and shear-thinning behavior. Furthermore, oscillatory measurements showed a prevailing viscous character, but the decrease of the extraction temperature resulted in an increase of both G' and G". Therefore, SFG extracted at low extraction temperatures showed higher viscous and elastic properties, while high extraction temperatures increased the antioxidant activity.

The effect of data exchange protocols on decision support systems for heart sounds.

Heart auscultation is one of the basic exams performed during a patient physical examination, but it is also one that has a high skill ceiling. Decision support systems can provide physicians with a tool that can help to reduce the demanding skill requirements of this exam. Nevertheless, this second opinion needs to be delivered in a timely interval in order to be truly useful for a physician. To do this we need not only optimized algorithms, but also a well designed system. In this paper, we have studied how two different data exchange protocols, that define how data should be transferred from an acquisition to a process module, can impact the celerity of delivering second opinion to a physician. With data collected from real exams, acquired in a field hospital initiative in Brazil, we recreated two use cases that allowed us to measure performance in the form of time and resources spent, as well as power consumption. Results have shown that different data exchange protocols can have a significant impact on a decision support system response time.

Phthiraptera and Gamasida parasites of Columbina picui (Temminck) (Columbiformes: Columbidae) in the State of Rio Grande do Sul, Southern Brazil.

Thirty-two specimens of Columbina picui (picui ground-dove) were examined, and a collection of arthropods was made by washing the external surface of the body and the nasal cavity. The species in the order Phthiraptera found and their respective prevalences, mean abundance and mean intensity were: Columbicola passerinae (84.4%; 10.3; 12.2), Hohorstiella passerinae (21.9%; 0.7; 3.1) and Physconelloides eurysema (3.1%; 0.1; 2). The gamasid mites found in the birds and their respective prevalences, mean abundance and mean intensity were: Pellonyssus marui (31.3%; 1.2; 3.9), Ornithonyssus bursa (15.6%; 0.2. ;1.2) and Mesonyssus sp. (6.3%; 0.1; 1). Columbicola passerinae, H. passerinae, P. eurysema, O. bursa, P. marui and Mesonyssus sp. were recorded for the first time infecting C. picui in Brazil. Except for O. bursa, the other species are reported for the first time in the state of Rio Grande do Sul, Brazil.

Nasal mites (Gamasida: Rhinonyssidae) of Paroaria coronata (Miller) (Passeriformes: Emberezidae).

With the aim of identifying the species of nasal mites of Paroaria coronata (red-crested cardinal), the nasal cavity of 40 birds were examined. The nasal mites were identified as Ptilonyssus sairae de Castro and Sternostoma pirangae Pence, with 50% and 7.5% of prevalence, respectively. This is the first record of these mite species parasitizing P. coronata. This report also amplifies the area of occurrence of S. pirangae for Brazil and that of P. sairae for Rio Grande do Sul, Brazil.

In vitro degradation of poly-L-D-lactic acid (PLDLA) pellets and powder used as synthetic alloplasts for bone grafting.

UNLABELLED: The objective of this study was to evaluate the in vitro degradation of pellet and powder forms of a poly-L-D-lactic acid material used to produce plates and screws for orthopedic, oral, and maxillofacial applications. MATERIALS AND METHODS: In order to produce the powder form the as-received pellets were milled in a cryogenic chamber. Particles size distribution (PSD) histograms were developed for both forms. The materials were then characterized by Scanning Electron Microscopy (SEM), Differential Scanning Calorimetry (DSC), and Thermogravimetric Analysis (TGA) before and after immersion in simulated body fluid for 30, 60, and 90 days. RESULTS: SEM showed that for both forms material degradation started after 30 days of immersion in SBF and evolved until 90 days. Degradation started at the amorphous zones of the polymer and exposed of deeper crystalline layers. The pellet and powder samples PSD showed polydispersed patterns with mean diameters of 673.98 microm and 259.55 microm. Thermal onset degradation temperatures were 365.64 degrees C and 360.30 degrees C, and of 363.49 degrees C and 359.83 degrees C before immersion and after 90 days in SBF for the pellet and powder forms, respectively. The Tg's of the pellets and the powder were approximately 61.5 degrees C and 66 degrees C, and their respective endothermic peaks were observed at approximately 125 degrees C and 120 degrees C. The specific heat (c) was approximately 8.5 J/g and 6.2 J/g for the pellet and powder material, respectively. CONCLUSION: According to the results obtained, cryogenic milling resulted in particle plastic deformation, and alterations in glass transition temperature, melting temperature, and specific heat of the material.

Chromosome instability in industrial strains of Saccharomyces cerevisiae batch cultivated under laboratory conditions.

Industrial ethanol fermentation is a complex microbiological process to which yeast cells must adapt for survival. One of the mechanisms for adaptation is thought to involve chromosome rearrangements. We found that changes in chromosome banding patterns measured by pulsed-field gel electrophoresis can also be produced in laboratory media under simulated industrial conditions. Based on analysis of their generational variation, we found that these chromosome changes were specific to the genetic backgrounds of the initial strains. We conclude that chromosome rearrangements could be one of the factors involved in yeast cell adaptation to the industrial environment.

Chromosome instability in industrial strains of Saccharomyces cerevisiae batch cultivated under laboratory conditions

Industrial ethanol fermentation is a complex microbiological process to which yeast cells must adapt for survival. One of the mechanisms for adaptation is thought to involve chromosome rearrangements. We found that changes in chromosome banding patterns measured by pulsed-field gel electrophoresis can also be produced in laboratory media under simulated industrial conditions. Based on analysis of their generational variation, we found that these chromosome changes were specific to the genetic backgrounds of the initial strains. We conclude that chromosome rearrangements could be one of the factors involved in yeast cell adaptation to the industrial environment.

First report of ciconiphilus decimfasciatus (amblycera: menoponidae) in casmerodius albus (aves: ciconiiformes) from brazil / Primeiro relato de ciconiphilus decimfasciatus (amblycera: menoponidae) em casmerodius albus (aves: ciconiiformes) no brasil

ABSTRACT This article reports, for the first time in Brazil, the occurrence of the louse Ciconiphilus decimfasciatus parasitizing the great egret (Casmerodius albus) from the state of Rio Grande do Sul, southern Brazil.

RESUMO Este trabalho registra, pela primeira vez no Brasil, a ocorrência do piolho Ciconiphilus decimfasciatus parasitando garça-brancagrande (Casmerodius albus) no Estado do Rio Grande do Sul.

Parasitos de animais silvestres no rio grande do sul: i-piolhos de alguns anseriformes / Parasites of wild animals in the state of rio grande do sul, brazil: i - lice of some anseriformes

RESUMO É reportado pela primeira vez no Estado do Rio Grande do Sul e no Brasil, o parasitismo dos piolhos menoponídeos Dicteisia tristis em tachã (Chaunatorquata), Holomenopon brevithoracicum em cisne-de-pescoço-preto (Cygnus melancoryphus) e Holomenopon leucoxanthum em marrecão da Patagônia (Netta peposaca), hospedeiros pertencentes à ordem Anseriformes.

ABSTRACT The authors report for the first time in the State of Rio Grande do Sul, Brazil, the parasitism of the menoponid lice Dicteisia tristis on the southern screamer (Chauna torquata), Holomenopon brevithoracicum on the black-necked swan (Cygnus melancoryphus) and Holomenopon leucoxanthum on the rosy-billed pochard (Netta peposaca), all hosts from the Order Anseriformes.

Alpha-SM actin expression as prognostic indicator in IgA nephropathy (Berger's disease).

Recent studies have demonstrated that alpha-Smooth Muscle actin expression in glomerular and tubulointerstitial compartments of renal tissue could represent a prognostic marker in several renal diseases. Our objective was to identify the prognostic value of alpha-SM actin actin expression on the evolution of renal damage in Primary IgA nephropathy (Berger's disease). 43 patients followed up from 1988 to 1999 at the University Hospital, Faculty of Medicine of Ribeirão Preto, University of Sao Paulo, Brazil, was studied. Clinical-laboratory data were obtained from the medical records of the patients using a protocol containing name, race, gender, origin, profession, age at clinical presentation of the disease and personal and family history. The parameters assessed in the approach to IgA nephropathy were serum creatinine, creatinine clearance, serum albumin, total serum protein, 24 hours proteinuria, glycaemia, serum sodium, potassium, calcium and phosphorus ions, analysis of urinary sediment, serum complement profile, blood count, and renal biopsy. Morphological evaluation was performed by renal biopsy using common light and immunofluorescence microscopy. Immunohistochemical studies were performed using a murine monoclonal antibody to alpha-SM actin. Our data showed that alpha-SM actin expression in the glomerular and tubulointerstitial compartments are not correlated with unfavorable clinical course of primary IgA nephropathy.

Clonal spread of methicillin-resistant Staphylococcus aureus in a large geographic area of the United States.

Methicillin resistance in Staphylococcus aureus has rapidly increased over the last two decades. This increase is paralleled by the emergence of unique multi-resistant MRSA clones. In Brazil, Argentina, Uruguay, Portugal and Czech Republic a specific MRSA clone is widely spread, the so-called Brazilian epidemic clone. Another epidemic clone, the Iberian clone, is disseminated in Spain, Portugal, Belgium, Scotland, Italy, Germany and New York. Thus, a large number of hospital-acquired infections have been caused by specific MRSA clones. Using different molecular techniques for MRSA typing, we verified that two unique epidemic clones are spread over large geographic area in the US. In addition, we showed that a previously described MRSA clone type, the New York clone (I::A:A), is widely spread beyond the New York frontiers.

Isolation and molecular characterization of methicillin-resistant coagulase-negative staphylococci from nasal flora of healthy humans at three community institutions in Rio de Janeiro City.

We describe the isolation and molecular characterization of methicillin-resistant coagulase-negative staphylococci (MRCNS) from the nasal flora of healthy humans from three institutions located in Rio de Janeiro City. Swabs were obtained from the nares of students attending a non-residential public school and adults from two military quarters. Isolates of staphylococci were tested for the presence of the mecA gene by hybridization with a specific probe. S. epidermidis was the most frequent MRCNS (38 of the total 45 CNS isolated). Twenty-five percent of nasal staphylococcal carriers studied were colonized with MRCNS. Pulsed-field gel electrophoresis (PFGE) of SmaI-digested genomic DNA was carried out to study the clonality of the methicillin-resistant S. epidermidis (MRSE) isolates. In addition to cross-colonization among individuals belonging to the same institution, familial cross-colonization appeared to contribute to the spread of the methicillin-resistant isolates among two inter-communicable institutions. Indeed, the wide genomic diversity among the MRSE flora suggests that the spread of the mecA gene among these isolates might also have occurred via horizontal transmission. Despite the limited number of institutions analysed, it is reasonable to conclude that our data do not represent a situation unique to the three organizations but may reflect other communities in Rio with respect to transmission of MRCNS.

Myxoma of the mitral valve.

Only rarely do myxomas originate from the mitral valve. This is the report of a 49-year-old woman presenting with congestive heart failure. The diagnosis of an intracardiac tumor involving the anterior cuspid of the mitral valve was made by transesophageal echocardiography. The patient underwent surgery for tumor resection and plasty of the valve was made with reconstruction and preservation of the valve. The diagnosis of myxoma was confirmed by histology. This is the 23rd case of myxoma of the mitral valve reported in the literature.

The role of antigenically different virus neuraminidases as structures implicated in receptor-binding processes.

Influenza A viruses exhibit segmented nucleic acid coding for eight different proteins, two of them as glycoproteins exposed on their lipoprotein envelopes, hemagglutinin (HA) and neuraminidase (NA). Hemagglutinin exhibits receptor-binding activity while neuraminidase develops sialidase cleavage activity which acts on cell receptors. Influenza A strains responsible for human, avian, equine and porcine respiratory infections all over the world present antigenically different hemagglutinin (H1 to H14) and neuraminidase (N1 to N9) structures on their surface. The objective of the present investigation was to study the role of N2, N8, and N9, antigenically diverse neuraminidase structures of human (N2) and animal (N8 and N9) influenza viruses, in the receptor-binding process. Receptor-binding activity of N2 and N8 was analyzed by crossed tests using H3N2 and H3N8 antisera and the hemagglutination inhibition test as a model. Hemagglutinating activity of antigenically different N2 and N8 structures was demonstrable and was inhibited by homologous antisera (N2-H3N2, N8-H3N8) but not by heterologous antisera (N2-H3N8,N8-H3N2). This previously demonstrated N9 hemagglutinating activity was analyzed for receptor-binding specificity using hemagglutination tests and NeuAc alpha2,3Gal and NeuAc alpha2,6Gal derivatized erythrocytes. This highly purified N9 strain was obtained from a virus strain isolated from terns by Dr. Peter Colman (CSIRO Division of Biomolecular Engineering, Parkville, Victoria, Australia). It exhibited receptor-binding specificity for NeuAc alpha2,3Gal sequences, a property similar to that observed in hemagglutinins from avian strains. These results indicate the importance of antigenically different neuraminidase structures as alternative agents for developing receptor-binding activity.(ABSTRACT TRUNCATED AT 250 WORDS)

The role of antigenically different virus neuraminidases as structures implicated in receptor-binding processes

Influenza A viruses exhibit segmented nucleic acid coding for eight different proteins, two of them as glycoproteins exposed on their lipoprotein envelopes, hemagglutinin (HA) and neuraminidase (NA). Hemagglutinin exhibits recptor-binding activity while neuraminidase develps sialidase cleavage activity which acts on cell receptors. Influenza A strains responsible for human, avian, equine and porcine respiratory infections all over the world present antigenically different hemagglutinin (H1 to H14) and neutraminidase (N1 to N9) structures on their surface. The objective of the present investigation was study the role of N2, N8 and N9, anti-genically diverse neuraminidase structures of human (N2) and animal (N8 and N9) influenza viruses, in the receptor-binding process. REceptor-binding activity of N2 and N8 was anlyzed by crossed tests using H3N2 and H3N8 antisera and the hemagglutination inhibition test as a model. Hemangglutinating activity of antigenically different N2 and N8 structures was demonstrable and was inhibited by homologous antisera (N2-H3N2, N8-H3N8) but not by heterologous antisera (N2-H3-N8,N8-H3-N2). This previously demonstrated N9 hemagglutinating activity was analysed for receptor-binding specificity using hemagglutination test and NeuAc alpha2,3Gal and NeuAc alpha2,6Gal derivatized erythrocytes. This highly purified N9 strain was obtained from a virus strain isolated from terns by Dr. Peter Colman (CSIRO Division of Biomolecular Engineering, Parkville, Victoria, Australia)...

[Myocardial revascularization in left coronary trunk lesion in patients over 65 years old]. / Cirurgia de revascularização miocárdica na lesão do tronco da coronária esquerda em pacientes acima de 65 anos de idade.

PURPOSE: To study the short and long-term follow-up of patients with left main coronary artery disease (LMCAD) and age over 65 years, by comparing the results with patients under 65 years-old. METHODS: Twenty-two patients with LMCAD and mean age of 69 +/- 3.5 years (group I) were underwent isolated coronary artery bypass grafting (CABG) and compared to 31 patients with LMCAD, mean age of 54 +/- 7 years (group II), who also underwent isolated CABG. The life-table Kaplan-Meyer method was used to estimate the post-operative survival. The chi-square and Student "t" test were used when necessary. RESULTS: Despite higher operative mortality in group I (9.1% x 3.2%), the difference was statistically not significant. The operative morbidity was similar in both groups. Actuarial survival at 4 years was 85% in group I and 95% in group II. Actuarial survival free of cardiac events was 69% in group II and 75% in group II. CONCLUSION: The CABG is well tolerated and had low morbidity and acceptable mortality in old patients with LMCAD. The long-term survival in these patients was very similar to the younger patients.

New arenavirus isolated in Brazil.

A new arenavirus, called Sabiá, was isolated in Brazil from a fatal case of haemorrhagic fever initially thought to be yellow fever. Antigenic and molecular characterisation indicated that Sabiá virus is a new member of the Tacaribe complex. A laboratory technician working with the agent was also infected and developed a prolonged, non-fatal influenza-like illness. Sabiá virus is yet another arenavirus causing human disease in South America.