Investigation of genetic susceptibility to Mycobacterium tuberculosis (VDR and IL10 genes) in a population with a high level of substructure in the Brazilian Amazon region.

OBJECTIVES: Tuberculosis (TB) is an infectious and contagious disease that has been very influential in human history and presents high rates of mortality. The objective of this study was to investigate the association of VDR, IL10, and SLC11A1 gene polymorphisms with susceptibility to the presence of Mycobacterium tuberculosis infection. METHODS: A total of 135 patients with confirmed TB and 141 healthy individuals were included in the analysis. Blood samples were collected for DNA extraction. Genotyping of the polymorphisms in the VDR and IL10 genes was performed by real-time PCR, and genotyping of the polymorphisms in the SLC11A1 gene by conventional PCR, followed by visualization in polyacrylamide gel. The genomic ancestry was obtained using an autosomal panel with 48 insertion/deletion ancestry-informative markers. RESULTS: Polymorphisms TaqI (TT, p=0.004), FokI (CC and CC+CT, p=0.012 and p=0.003, respectively), and BsmI (GG, p=0.008) in the VDR gene, as well as A-592C (GC+AG, p=0.001) in the IL10 gene, were significantly associated with susceptibility to TB In addition, high production of VDR combined with low production of IL10 showed protection for the TB group (p=0.035). CONCLUSIONS: The VDR polymorphisms may confer an increased risk and the IL10 haplotype may be a protection factor for the presence of M. tuberculosis infection in the Brazilian population.

Efeito da somatotropina bovina recombinante (rbST) na produção in vivo e na maturação in vitro de oócitos bovinos da raça Sindi / Effect of recombinant bovine somatotropin (rbST) on the in vivo production and in vitro maturation of bovine oocytes of the Sindi breed

A fim de avaliar o efeito de diferentes doses da rbST sobre a dinâmica folicular, a produção e a maturação in vitro de oócitos, 20 vacas Sindi, divididas em três grupos, receberam um dispositivo de progesterona intravaginal, estradiol e PGF2α, além de 2mL de solução salina (grupo controle), 250 (grupo rbST 250) ou 500mg de rbST (grupo rbST 500). Cinco dias depois, realizou-se a ovum pick up, e os complexos cumulus-oócitos (CCOs) recuperados foram selecionados, classificados e maturados in vitro. Os dados de contagem foram comparados pelo procedimento glht (General Linear Hypothesis Test), e os dados em porcentagem foram submetidos ao qui-quadrado, no programa estatístico R, onde as diferenças foram consideradas significativas quando P<0,05. Não houve diferença (P>0,05) entre os grupos quanto à quantidade de folículos e à taxa de maturação. Os grupos rbST 250 e rbST 500 foram significativamente superiores (P<0,05) ao grupo controle em relação ao número de folículos grandes (0,42±0,20 vs. 0). O grupo rbST 500 apresentou maior (P<0,05) porcentagem de oócitos viáveis (91,52%) do que os grupos controle (67,85%) e rbST 250 (53,33%). A rbST aumenta o número de folículos grandes, e 500mg de rbST aumentam a porcentagem de oócitos viáveis em vacas Sindi.(AU)

In order to evaluate the effect of different doses of rbST on the follicular dynamics, production, and in vitro maturation of oocytes, 20 Sindhi cows were divided into three groups, receiving an intravaginal progesterone device, estradiol and PGF2α, and 2mL of solution saline (Control Group), 250 (rbST 250 Group) or 500mg rbST (rbST 500 Group). Five days later, the ovum pick up was performed, and the cumulus-oocyte (CCO) complexes recovered were selected, classified, and matured in vitro. The counting data were compared by the glht (General Linear Hypothesis Test) procedure, and the percentage data were submitted to Qui- square, in the statistical program R, where differences were considered significant when P< 0.05. There was no difference (P> 0.05) between the groups regarding follicle quantity and maturation rate. The rbST 250 and rbST 500 groups were significantly higher (P< 0.05) than the Control group in relation to the number of large follicles (0.42±0.20 versus 0). The rbST 500 group presented higher (P< 0.05) percentage of viable oocytes (91.52%) than the Control (67.85%) and rbST 250 (53.33%) groups. rbST increases the number of large follicles and 500mg rbST increases the percentage of viable oocytes in Sindhi cows.(AU)

Mice on menu: opportunistic feeding behaviour of the Amazonian silver arowana Osteoglossum bicirrhosum.

Two silver arowana, Osteoglossum bicirrhosum, one male (49.5 cm standard length, LS ) and one female (52.5 cm LS ) that had fed on small-eared colilargo or small-eared pygmy rice rat Oligoryzomys microtis, were sampled during the rising water period in the Brazilian Amazon. The identified prey were 6 and 8 cm long and occupied the entire stomachs of both individuals. This opportunistic feeding behaviour appears to be a strategy for this fish to acquire nutrients during times when its usual aquatic prey is dispersed throughout the flooded forest. This article is protected by copyright. All rights reserved.

Quercetin influences in vitro maturation, apoptosis and metabolically active mitochondria of goat oocytes.

SummaryThe present study aimed to investigate the effect of quercetin as an alternative antioxidant to cysteamine on in vitro maturation. Oocytes were collected from goat ovaries, destined for in vitro maturation and distributed into three groups: CIS group, oocytes were immersed in MIV base medium; in Groups Q4 and Q8, oocytes were immersed in the medium of the CIS group, adding 4 µM or 8 µM of quercetin, respectively, and cultured for 24 h at 38.5°C with 5% CO2. The CIS and Q4 groups presented the same percentage of expanded cumulus cells, but the per cent in the Q8 group was significantly lower than that of the other groups (P<0.05). The oocyte retraction rate in the Q8 group was higher (P<0.05) than in the CIS and Q4 groups. Treatment with 8 µM of quercetin presented a lower proportion of expanded oocytes than the CIS group and 4 µM of quercetin (P<0.05). The percentage of MII oocytes was higher in the Q4 group than in the CIS group (P<0.05), but the percentages in the CIS and Q8 groups were similar. The rate of apoptosis was higher in the CIS group than in the other groups (P<0.05). In addition, oocytes matured with 4 µM quercetin showed higher mitochondrial activity than matured oocytes in the CIS and Q8 groups (P<0.05). In conclusion, 4 µM of quercetin can be used as an alternative to cysteamine in the in vitro maturation of goat oocytes.

Loss of genetic diversity in farmed populations of Colossoma macropomum estimated by microsatellites.

The genetic variability of four Colossoma macropomum broodstocks, three from fish farms in different regions and one from the natural environment in Brazil, was analyzed using microsatellite markers. The wild progeny (n = 30) were caught in the Solimões-Amazonas River, at the varzea lakes; this location is used to mature the fish from larvae to juveniles. The three fish farms were selected according to the age of their lineages and broodstock availability: DNOCS (n = 21) is located in the Ceará State, representing the oldest lineage of cultivated tambaqui in Brazil; Balbina (n = 30) is located in the Amazonas State, representing the youngest stocks of tambaqui farmed in Brazil (approximately 15 years); and UFRPE (n = 30) is located in the Pernambuco State and is considered to be a mixed stock formed from the DNOCS and Balbina lineages. The analysis of 13 microsatellite loci indicated the occurrence of a variability reduction in the farmed populations; the UFRPE stock was the population with the highest diversity level. Low values of molecular coancestry were found in these populations. Additionally, significant differences in the RST values among the populations were detected, as was the occurrence of genetic structure. The genetic loss found in these populations may have been influenced by the founder effect. Because no breeding programs were during the entire production period and no pedigree records were kept for these broodstocks, we suggest that a wild population might be used as an important genetic resource to increase the genetic diversity of renewal stock lineages.

Influência do parasitismo intestinal sobre os parâmetros hematológicos e de líquido peritoneal em equinos de tração / Influence of intestinal parasitism on peritoneal fluid and hematological parameters in horses used for traction

O objetivo do presente estudo foi avaliar a influência do parasitismo intestinal crônico sobre parâmetros hematológicos e de líquido peritoneal por meio da comparação dessas características em equinos naturalmente parasitados e após administração de anti-helmíntico. Utilizaram-se 21 cavalos de tração urbana, entre dois e 19 anos, sem raça definida e com resultado de exame parasitológico superior a 300 ovos por grama de fezes. Foi realizada avaliação física e coleta de fezes, de líquido peritoneal e de sangue em dois momentos do experimento (D0 e D15), sendo efetuado tratamento antiparasitário no D0. No fluido peritoneal foram avaliadas características físicas, bioquímicas, bem como contagem de células nucleadas (CTCN) e diferenciação celular. No sangue foram determinados valores eritrocitários, leucocitários, proteínas plasmáticas totais, glicose e fibrinogênio plasmáticos, além de fosfatase alcalina (FA) sérica. A análise dos parâmetros avaliados não demonstrou diferença significativa entre animais parasitados e após administração de anti-helmíntico, exceto para valores de CTCN, contagem de neutrófilos segmentados e grau de turbidez do líquido peritoneal. As médias se mantiveram dentro dos intervalos de referência, com exceção da CTCN do líquido peritoneal no D0. No líquido peritoneal, houve predomínio de neutrófilos segmentados, seguidos por macrófagos, linfócitos e eosinófilos em ambos os momentos de avaliação. Observaram-se tendência do quadro eritrocitário em manter-se próximo aos limites inferiores e leve leucocitose no D0. A infecção parasitária nos animais estudados foi predominantemente moderada, o que oferece poucos riscos clínicos. Nessas condições, pode-se afirmar que a CTCN, a contagem absoluta de neutrófilos segmentados e o grau de turbidez do líquido peritoneal são influenciados e podem ser considerados ferramentas diagnósticas e prognósticas úteis nas parasitoses intestinais crônicas.(AU)

The aim of this study was to evaluate the influence of chronic intestinal parasitism on hematological parameters and peritoneal fluid. It was done by comparing these features in horses used for traction naturally parasitized and after the administration of anthelmintic. Twenty-one horses, between two and nineteen years of age, of mixed breed and with results of parasitological examination of more than 300 eggs per gram of feces were studied. Physical assessment and samples of feces were conducted, as well as blood and peritoneal fluid in the two phases of the experiment (D0 and D15). Antiparasitic treatment in D0 has also been done. The peritoneal fluid was evaluated for physical and biochemical features, and also total count of nucleated cells (TCNC) and cell differentiation. The blood was determined for erythrocyte, leukocyte, plasma total protein, glucose and plasma fibrinogen, and alkaline phosphatase (ALP) levels. The analysis of these parameters showed no significant difference between parasitized animals and after administration of anthelmintic except for TCNC values, segmented neutrophil count and degree of turbidity in peritoneal fluid. The averages remained within the reference ranges, except the TCNC in the peritoneal fluid in D0. In the peritoneal fluid there was a predominance of segmented neutrophils, followed by macrophages, lymphocytes and eosinophils in both time points. A trend was observed in erythrocyte frame to keep close to the lower limits and mild leukocytosis in D0. Parasitic infection of the animals studied was predominantly moderate, which offered minimal clinical risks. After that, it can be affirmed that the TCNC, absolute segmented neutrophil count and targeted degree of turbidity in peritoneal fluid are influenced and can be considered useful diagnostic and prognostic tools in chronic intestinal parasitism.(AU)

Short- and long-term theory-based predictors of physical activity in women who participated in a weight-management program.

This study analyzed psychosocial predictors of the Theory of Planned Behavior (TPB) and Self-Determination Theory (SDT) and evaluated their associations with short- and long-term moderate plus vigorous physical activity (MVPA) and lifestyle physical activity (PA) outcomes in women who underwent a weight-management program. 221 participants (age 37.6 ± 7.02 years) completed a 12-month SDT-based lifestyle intervention and were followed-up for 24 months. Multiple linear regression analyses tested associations between psychosocial variables and self-reported short- and long-term PA outcomes. Regression analyses showed that control constructs of both theories were significant determinants of short- and long-term MVPA, whereas affective and self-determination variables were strong predictors of short- and long-term lifestyle PA. Regarding short-term prediction models, TPB constructs were stronger in predicting MVPA, whereas SDT was more effective in predicting lifestyle PA. For long-term models, both forms of PA were better predicted by SDT in comparison to TPB. These results highlight the importance of comparing health behavior theories to identify the mechanisms involved in the behavior change process. Control and competence constructs are crucial during early adoption of structured PA behaviors, whereas affective and intrinsic sources of motivation are more involved in incidental types of PA, particularly in relation to behavioral maintenance.

Ectopia ureteral unilateral congênita em uma cadela Teckel Dachshund com pelagem arlequim: relato de caso / Single congenital ureteral ectopy in a female dog Teckel Dachshund with merle colour pattern: case report

O presente relato apresenta a primeira descrição de ectopia ureteral congênita na raça Teckel Dachshund, diagnosticada em uma cadela com pelagem arlequim. O animal, aos dois meses de idade, apresentava sinais de incontinência urinária e cistite bacteriana, sendo submetido a um plano diagnóstico para confirmação de ureter ectópico. A urografia excretora revelou hidroureter direito com desembocadura caudal ao trígono da bexiga. O exame físico do animal evidenciou ainda hérnia inguinal bilateral, o que reforçou a caracterização da origem congênita das alterações. Aspectos de bem-estar animal são também discutidos.

The present work reports the first description of congenital ureteral ectopy in the canine breed Teckel Dachshund, diagnosed in a female dog with merle colour pattern. The two month old animal, presented with continuous dribbling of urine and bacterial cystitis, was subjected to a diagnostic plan for ectopic ureter. The excretory urography showed a right hidroureter, which had an orifice located caudally to the trigone of the bladder. The animal also presented a bilateral inguinal hernia, which confirmed the case description as a multiple congenital anomaly condition. Animal welfare aspects are also discussed.

Cáncer de próstata: biomarcadores prometedores relacionados con la enfermedad agresiva / Prostate Cancer: Promising Biomarkers Related to Aggressive Disease

Antecedentes: A pesar del número rápidamente creciente de marcadores biológicos de pronóstico y/o respuesta a tratamientos específicos posibles en el cáncer de próstata, ninguno ha mostrado hasta la fecha la capacidad de pronosticar por completo el cáncer de próstata en la urología basada en la evidencia. Objetivo: Revisar la literatura pertinente sobre el tema. Adquisición de evidencia: Se llevó a cabo una revisión exhaustiva de la literatura actual centrándose en los prometedores biomarcadores relacionados con el cáncer de próstata agresivo. Resumen de la evidencia: En combinación con la naturaleza heterogénea de la enfermedad, las series de casos mixtas son el diseño de estudio más común, que impiden resultados sólidos y el desarrollo de una estrategia terapéutica eficaz. La mejora de la supervivencia del paciente con cáncer de próstata requiere no solo la identificación de un nuevo objetivo terapéutico, basado en la comprensión detallada de los mecanismos biológicos implicados en la diseminación metastásica y el crecimiento del tumor, sino también consistentes estudios clínicos. Conclusión: Se necesita un mejor diseño de estudio implicando los marcadores potenciales e incluyendo a los pacientes bien clasificados y por estadios, con una metodología sólida y los resultados adecuados (sobre todo la supervivencia) para la evolución en este campo (AU)

Background: Although a rapidly growing number of candidate biological markers of prognosis and/or response to specific treatments in prostate cancer, none have to date showed ability to completely prognosticate prostate cancer on evidence based urology. Objective: To review the pertinent literature on the issue. Acquisition of evidence: A comprehensive review of the current literature was done focusing on promising biomarkers related to aggressive prostate cancer. Summary of evidence: Combined with the heterogeneous nature of the disease, mixt case series are the most common study design, impeding robust results and the development of an effective therapeutic strategy. Improvement in prostate cancer patient survival requires not only the identification of new therapeutic target based on detailed understanding of the biological mechanisms involved in metastatic dissemination and tumor growth but strong clinical studies as well. Conclusion: Better study design involving potential markers and including well-classified and staged patients with robust methodology and adequate outcomes (mainly survival) are necessary to the field evolution (AU)

Comparative cytogenetics of spiny rats of the genus Proechimys (Rodentia, Echimyidae) from the Amazon region.

We made a comparative analysis of the cytogenetics of spiny rat species of the genus Proechimys collected from several sites of the Madeira River basin (Amazonas State, Brazil) and Jari River valley (Pará State, Brazil). Individuals were assigned to three groups based on diploid and fundamental numbers: 2n = 28, FN = 46 (P. cuvieri and P. gr. longicaudatus); 2n = 38, FN = 52 (Proechimys gr. guyannensis), and 2n = 40, FN = 54 (P. gardneri). The nucleolar organizer region (NOR) was interstitial on the long arm of one submetacentric pair, as seen in all species of Proechimys analyzed thus far. However, its position in the karyotype was variable. A duplication of the NOR in one of the homologues was detected in P. gr. longicaudatus from the Aripuanã basin along the mid Madeira. The C-band pattern varied between species and, together with the NOR, allowed the identification of two evolutionary units in P. gr. longicaudatus in the region of the mid Madeira River (cytotypes A and B). The morphology and banding of the sex chromosomes were species specific. A range extension is suggested for the geographic distribution of P. gardneri and P. gr. longicaudatus. Moreover, we suggest that species of Proechimys with 2n = 38 chromosomes are restricted to east of the Negro River and north of the Amazon River. We also revised the published chromosome data available for Proechimys.

[Prostate cancer: promising biomarkers related to aggressive disease]. / Cáncer de próstata: biomarcadores prometedores relacionados con la enfermedad agresiva.

BACKGROUND: Although a rapidly growing number of candidate biological markers of prognosis and/or response to specific treatments in prostate cancer, none have to date showed ability to completely prognosticate prostate cancer on evidence based urology. OBJECTIVE: To review the pertinent literature on the issue. ACQUISITION OF EVIDENCE: A comprehensive review of the current literature was done focusing on promising biomarkers related to aggressive prostate cancer. SUMMARY OF EVIDENCE: Combined with the heterogeneous nature of the disease, mixed case series are the most common study design, impeding robust results and the development of an effective therapeutic strategy. Improvement in prostate cancer patient survival requires not only the identification of new therapeutic target based on detailed understanding of the biological mechanisms involved in metastatic dissemination and tumor growth but strong clinical studies as well. CONCLUSION: Better study design involving potential markers and including well-classified and staged patients with robust methodology and adequate outcomes (mainly survival) are necessary to the field evolution.

Use of habitats by non-volant small mammals in Cerrado in Central Brazil.

Non-volant small mammals are organisms capable of yielding precise information on richness, abundance and species composition variations related to the use of habitats. The aim of this research was to compare these variations in Cerrado sensu stricto, Palm Forest, Gallery Forest and Rocky Field. From May 1999 to February 2000, we surveyed non-volant small mammals (hence small mammals) in Serra das Araras Ecological Station. We captured 218 individuals and recaptured 62 individuals, belonging to 21 taxa, 13 rodents and eight marsupials, in a total of 13200 trap-nights. Capture success was 1.7%. We observed higher richness of small mammals in forested areas (Gallery Forest and Palm Forest) than in open areas (Rocky Field and Cerrado sensu stricto). The Palm Forest had the highest richness of marsupials, possibly due to the quality of a specific niche. The Rocky Field had the smallest richness, but with very high abundance of few species, mainly Thrichomys pachyurus and Monodelphis domestica. Forest habitats had similar species composition. The open habitats, Cerrado sensu stricto and Rocky Field, had a distinct species composition between them, and also when compared to forested areas. Different species are exclusive or showed preference for specific habitats. The protection of horizontally heterogeneous biomes, such as Cerrado, has a fundamental importance to the maintenance of the regional diversity of the small mammal community of Central Brazil.

Identification of genes encoding hypothetical proteins in open-reading frame expressed sequence tags from mammalian stages of Trypanosoma cruzi.

Approximately 50% of the predicted protein-coding genes of the Trypanosoma cruzi CL Brener strain are annotated as hypothetical or conserved hypothetical proteins. To further characterize these genes, we generated 1161 open-reading frame expressed sequence tags (ORESTES) from the mammalian stages of the VL10 human strain. Sequence clustering resulted in 435 clusters, consisting of 339 singletons and 96 contigs. Significant matches to the T. cruzi predicted gene database were found for ~94% contigs and ~69% singletons. These included genes encoding surface proteins, known to be intensely expressed in the parasite mammalian stages and implicated in host cell invasion and/or immune evasion mechanisms. Among 151 contigs and singletons with similarity to predicted hypothetical protein-coding genes and conserved hypothetical protein-coding genes, 83% showed no match with T. cruzi EST and/or proteome databases. These ORESTES are the first experimental evidence that the corresponding genes are in fact transcribed. Sequences with no significant match were searched against several T. cruzi and National Center for Biotechnology Information non-redundant sequence databases. The ORESTES analysis indicated that 124 predicted conserved hypothetical protein-coding genes and 27 predicted hypothetical protein-coding genes annotated in the CL Brener genome are transcribed in the VL10 mammalian stages. Six ORESTES annotated as hypothetical protein-coding genes showing no match to EST and/or proteome databases were confirmed by Northern blot in VL10. The generation of this set of ORESTES complements the T. cruzi genome annotation and suggests new stage-regulated genes encoding hypothetical proteins.

Chronic exercise reduces platelet activation in hypertension: upregulation of the L-arginine-nitric oxide pathway.

Nitric oxide (NO) inhibits platelet function and plays a key role in the regulation of cardiovascular homeostasis. Essential hypertension is characterized by an increased risk of thrombus formation, and by an inhibition of intraplatelet NO bioactivity. We have previously shown that membrane transport of L-arginine is a rate-limiting step for platelet-derived NO synthesis. This study examined the effects of exercise on the platelet L-arginine-NO pathway and aggregation and systemic inflammation markers in 13 sedentary hypertensive patients subjected to 60 min of training activity (exercise group), predominantly aerobic, three times a week for a period of 12 weeks. Six sedentary hypertensive patients participated in the control group. After 12 weeks, L-arginine transport was significantly increased and associated with increased platelet NO synthase activity and cGMP levels and reduced platelet aggregation. Moreover, exercise training reduced plasma concentrations of fibrinogen and C-reactive protein and blood pressure. The control group did not change their previous intraplatelet L-arginine-NO results and systemic inflammatory markers levels. Thus, exercise training reduces inflammatory responses, restores NO synthesis in platelets and thereby contributes to the beneficial effects of exercise in hypertension. The present study adds exercise as a new tool to reduce morbidity and mortality associated with platelet activation in hypertension.

Ion fluxes and hematological parameters of two teleosts from the Rio Negro, Amazon, exposed to hypoxia.

The aim of this study was to describe the effect of hypoxia on whole body ion fluxes and hematological parameters in two Amazonian teleosts: Serrasalmus eigenmanni and Metynnis hypsauchen. The increase of Na+ and Cl- effluxes on M. hypsauchen exposed to hypoxia may be related to an increase of gill ventilation and effective respiratory surface area, to avoid a reduction in the oxygen uptake, and/or with the decrease of pHe, that could inhibit Na+ and Cl- transporters and, therefore, reduce influx of these ions. Effluxes of Na+ and Cl- were lower in hypoxia than in normoxia for S. eigenmanni, possibly because in hypoxia this species would reduce gill ventilation and oxygen uptake, which would lead to a decrease of gill ion efflux and, consequently, reducing ion loss. The increase on hematocrit (Ht) during hypoxia in M. hypsauchen probably was caused by an increase of the red blood cell volume (MCV). For S. eigenmanni the increase on glucose possibly results from the usage of glucose reserve mobilization. Metynnis hypsauchen showed to be more sensitive to hypoxia than Serrasalmus eigenmanni, since the first presented more significant alterations on these osmoregulatory and hematological parameters. Nevertheless, the alterations observed for both species are strategies adopted by fishes to preserve oxygen supply to metabolizing tissues during exposure to hypoxia.

Ion fluxes and hematological parameters of two teleosts from the Rio Negro, Amazon, exposed to hypoxia / Fluxos iônicos e parâmetros hematológicos em duas espécies de teleósteos do Rio Negro, Amazônia, expostos à hipoxia

The aim of this study was to describe the effect of hypoxia on whole body ion fluxes and hematological parameters in two Amazonian teleosts: Serrasalmus eigenmanni and Metynnis hypsauchen. The increase of Na+ and Cl- effluxes on M. hypsauchen exposed to hypoxia may be related to an increase of gill ventilation and effective respiratory surface area, to avoid a reduction in the oxygen uptake, and/or with the decrease of pHe, that could inhibit Na+ and Cl- transporters and, therefore, reduce influx of these ions. Effluxes of Na+ and Cl- were lower in hypoxia than in normoxia for S. eigenmanni, possibly because in hypoxia this species would reduce gill ventilation and oxygen uptake, which would lead to a decrease of gill ion efflux and, consequently, reducing ion loss. The increase on hematocrit (Ht) during hypoxia in M. hypsauchen probably was caused by an increase of the red blood cell volume (MCV). For S. eigenmanni the increase on glucose possibly results from the usage of glucose reserve mobilization. Metynnis hypsauchen showed to be more sensitive to hypoxia than Serrasalmus eigenmanni, since the first presented more significant alterations on these osmoregulatory and hematological parameters. Nevertheless, the alterations observed for both species are strategies adopted by fishes to preserve oxygen supply to metabolizing tissues during exposure to hypoxia.

O objetivo deste trabalho foi descrever o efeito da hipoxia no fluxo iônico corporal e nos parâmetros hematológicos em duas espécies de teleósteos da Amazônia: Serrasalmus eigenmanni e Metynnis hypsauchen. O aumento dos efluxos de Na+ e Cl- em M. hypsauchen expostos à hipoxia pode estar relacionado ao aumento da ventilação branquial e da eficiência da área da superfície respiratória, a fim de evitar redução na captação de oxigênio; e/ou com a diminuição do pHe, que pode inibir os transportadores de Na+ e Cl- e, então, reduzir o influxo destes íons. Os efluxos de Na+ e Cl- foram menores em hipoxia do que em normoxia para a espécie S. eigenmanni, possivelmente porque esta espécie em hipoxia poderia reduzir a ventilação branquial e a captação de oxigênio, a qual levaria a uma diminuição do efluxo branquial de íons e, conseqüentemente, à redução da perda de íons. O aumento do hematócrito (Ht) durante hipoxia em M. hypsauchen provavelmente foi causado pelo aumento do volume das células vermelhas do sangue (MCV). Para a espécie S. eigenmanni, o aumento da glicose possivelmente foi resultado do uso da mobilização da reserva de glicose. A espécie Metynnis hypsauchen mostrou ser mais sensível à hipoxia do que a espécie Serrasalmus eigenmanni, uma vez que a primeira espécie apresentou mais alterações significativas em seus parâmetros osmorregulatórios e hematológicos. Contudo, as alterações observadas em ambas as espécies são estratégias adotadas pelos peixes a fim de preservar o suprimento de oxigênio para metabolização nos tecidos durante exposição à hipoxia.

Quantifying the biodiversity value of tropical primary, secondary, and plantation forests.

Biodiversity loss from deforestation may be partly offset by the expansion of secondary forests and plantation forestry in the tropics. However, our current knowledge of the value of these habitats for biodiversity conservation is limited to very few taxa, and many studies are severely confounded by methodological shortcomings. We examined the conservation value of tropical primary, secondary, and plantation forests for 15 taxonomic groups using a robust and replicated sample design that minimized edge effects. Different taxa varied markedly in their response to patterns of land use in terms of species richness and the percentage of species restricted to primary forest (varying from 5% to 57%), yet almost all between-forest comparisons showed marked differences in community structure and composition. Cross-taxon congruence in response patterns was very weak when evaluated using abundance or species richness data, but much stronger when using metrics based upon community similarity. Our results show that, whereas the biodiversity indicator group concept may hold some validity for several taxa that are frequently sampled (such as birds and fruit-feeding butterflies), it fails for those exhibiting highly idiosyncratic responses to tropical land-use change (including highly vagile species groups such as bats and orchid bees), highlighting the problems associated with quantifying the biodiversity value of anthropogenic habitats. Finally, although we show that areas of native regeneration and exotic tree plantations can provide complementary conservation services, we also provide clear empirical evidence demonstrating the irreplaceable value of primary forests.

Peripheral blood levels of thyroglobulin mRNA and serum thyroglobulin concentrations after radioiodine ablation of multinodular goiter with or without pre-treatment with recombinant human thyrotropin.

We investigated the effect of therapeutic doses of radioiodine (RAI) on peripheral serum messenger thyroglobulin RNA (Tg mRNA) and serum thyroglobulin (sTg) in patients with multinodular goiter (MNG) preceded or not by treatment with recombinant human TSH (rhTSH). Fourteen patients with large MNG (91-542 ml) received RAI (550-2960 MBq). Half of the patients received 0.45 mg of rhTSH prior to the treatment (RAI+rhTSH group) and half did not (RAI group). Patients' blood samples were collected before and 24, 48, and 72 h; 7 and 30 days; and 6, 9, and 12 months after RAI treatment. Serum Tg was measured by immunoradiometric assay, serum anti-Tg by radioimmunoassay, and quantification of circulating Tg mRNA was performed by real-time PCR. The shrinkage of MNG volume was documented by serial computed tomography (CT) scans before, 6 and 12 months after RAI. Peak Tg mRNA and sTg were reached earlier in the RAI+rhTSH group (24 h and 48 h) than in the RAI group (7 days). Both declined after the peak and the lowest levels were observed at 12 months. The mean reduction of the thyroid volume was 19.8% (RAI group) and 30.3% (RAI+rhTSH group) at 6 months (ns) and 32.8% RAI and 52.5% (RAI+rhTSH group) at 12 months (p<0.05). After RAI treatment there was a significant and positive correlation between goiter volume and sTg only in the RAI group (r=0.7; p=0.032). Serum anti-Tg had a transitory and relatively small elevation in 3 and 2 patients, respectively, in the RAI and RAI+rhTSH groups. We concluded that after RAI ablation of MNG there is a rapid release of Tg into the serum possibly from the colloid, which is followed by an elevation of serum Tg mRNA that may be due to an increased release of follicular cells into the blood stream. Both phenomena are enhanced by the use of rhTSH before RAI treatment as a consequence of a more effective and prolonged radiation exposure of the thyroid follicles.

Lung disease features in Brazilian children with HIV infection before HAART era.

Lower respiratory tract diseases are major causes of morbidity and mortality in HIV infected children. We studied the lung disease features associated with AIDS in children and adolescents, in an era of ineffective antiretroviral therapy, between January 1996 and October 1998. This prospective, descriptive, longitudinal and historical medical chart review included 48 vertically HIV infected patients, receiving mono or double antiretroviral therapy, who had developed pulmonary disease. Those who presented acute pneumonia were classified into group 1; radiological changes for >or=3 months into group 2; those from group 1 and 2 who underwent lung biopsy into group 3. A rapidly progressive clinical course was found in 70.7% of the children and 37.5% younger than 6 months old. Bacterial pneumonia was diagnosed in all patients. High resolution chest computer tomographic scans (HRCT) from 27 patients showed a reticulonodular pattern in 8, ground-glass in 3, reticular in 3, nodular in 3, airspace consolidation in 3, mediastinal adenopathy in 3, pulmonary air cystic in 2 and air-trapping in 1. In five patients the HRCT were normal. Histopathology revealed: lymphoid interstitial pneumonitis in 5 patients, pulmonary lymphoid hyperplasia in 9, tuberculosis in 1, interstitial pneumonia in 1, diffuse alveolar damage in 1. Two patients had Cryptococcus neoformans and Mycobacterium tuberculosis. We conclude that lung diseases were the major risk factor for high morbidity, and an invasive diagnostic procedure may clarify the main cause for similar radiologic images of infectious and non-infectious processes.