MAURICE MARTEL et PAUL MARTEL, La compagnie au Québec. Les aspects juridiques, Montréal, Wilson & Lafleur Ltée/Martel Ltée, 1989, 1019 p., ISBN 2-920831-06-2. Deuxième édition, 1990, 1021 p., ISBN 2-920831-20-8.

The seasonal variation of the protozooplanktonic community (ciliates and testate amoebae) was studied in a tropical oligotrophic reservoir in Brazil, which was under the influence of two contrasting climatic seasons (rainy/warm and dry/cold). The aim of this study was to evaluate the effect of these climatic changes on physical, chemical and biological variables in the dynamic of this community. The highest mean density of total protozoans occurred in the rainy/warm season (5683.2 ind L-1), while the lowest was in the dry/cold (2016.0 ind L-1). Considering the seasonal variations, the protozoan groups that are truly planktonic, such as the oligotrichs (Spirotrichea), predominated in the dry season, whereas during the rainy season, due to the material input and resuspension of sediment, sessile protozoans of the Peritrichia group were the most important ones. The dominant protozoans were Urotricha globosa, Cothurnia annulata, Pseudodifflugia sp. and Halteria grandinella. The highest densities of H. grandinella were associated with more oxygenated and transparent water conditions, while the highest densities of C. annulata occurred in sites with high turbidity, pH and trophic state index (TSI). The study demonstrated that density and composition of protozooplanktonic species and groups of the reservoir suffered seasonal variation due to the environmental variables (mainly temperature, turbidity, water transparency, dissolved oxygen and TSI) and the biological variables (e.g. morphological characteristics, eating habits and escape strategies from predation of the species).Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

“In vitro” evaluation of the bacterivore potential of three Cladoceran species occurring in tropical and subtropical regions

Abstract Cladocerans occupy an important position among the bacterial consumers in freshwater food webs, being relatively non-selective filter feeders that can exert a strong impact on microbial populations. We evaluated the bacterivory potential of three cladocerans species of subtropical and tropical occurrence (Ceriodaphnia silvestrii, Daphnia gessneri and Ceriodaphnia cornuta) at different life stages, by scanning electron microscopy (SEM) and by the quantification of their bacterial consumption rates using fluorescently labeled bacteria (FLB). All species showed filter mesh sizes sufficiently narrow to retain bacteria. The largest distance between setules was found in primiparous C. cornuta, and the smallest in neonate D. gessneri. The lowest ingestion (IR) and removal (RR) rates were observed in primiparous C. silvestrii and the highest values were observed in adults of D. gessneri. We conclude that bacteria may be considered an important food supplement, particularly for neonates who presented smaller intersetular distances and higher filtration rates than the other life stages

Cerebral biopsy: comparison between frame-based stereotaxy and neuronavigation in an oncology center Biópsia cerebral: comparação entre estereotaxia com arco e neuronavegação em um centro de oncologia

Treatment of intracranial tumoral lesions is related to its correct histological diagnostic. We present a retrospective analysis of 32 patients submitted to 36 cerebral biopsies using neuronavigation and 44 patients using frame-based stereotaxy. Mean age was 46.6 and 49.3 years old respectively. Sex distribution in both groups was 50% for each. Most of lesions were lobar in both groups. Diagnostic yielding was 91.7% and 83.4%, respectively (p=0.26). We found in the postoperative CT scans intracranial hemorrhages in 13.8% cases of the first group and 9.8% cases in the second. Most of them were mild post-operative hemorrages in the biopsy site. There was one death related to the procedure in each group. Astrocytomas and metastatic adenocarcinomas were the most frequent diagnosis. Diagnostic yielding and the number of postoperative hemorrhage and death were similar on both groups and the same found in the literature.<br>O manejo das lesões intracranianas tumorais está relacionado ao seu diagnóstico histológico adequado. Foi realizado estudo retrospectivo com 32 pacientes submetidos a 36 biópsias cerebrais por neuronavegação e 44 pacientes por estereotaxia com arco. A idade média foi 46,6 e 49,3 anos respectivamente. Nos dois grupos a distribuição por sexo foi 50% para cada. A maioria das lesões biopsiadas eram lobares nos dois grupos. A positividade diagnóstica foi 91,7% para neuronavegação e 83,4% para a estereotaxia com arco, respectivamente (p=0,26). Identificou-se hemorragia intracraniana na TC pós-operatória em 13,8% dos casos no primeiro grupo e em 9,8% no segundo, a maioria de pequena monta sem provocar piora neurológica. Ocorreu uma morte relacionada ao procedimento em cada grupo. Os diagnósticos mais freqüentes foram astrocitomas e adenocarcinomas metastáticos. A positividade diagnóstica, taxas de hemorragia pós-operatória e de mortalidade foram equiparáveis estatisticamente entre os dois métodos e se assemelham com as descritas na literatura