Systematic review of dietary intervention trials to lower blood total cholesterol in free-living subjects

Objectives: To estimate the efficacy of dietary advice to lower blood total cholesterol concentration in free-living subjects and to investigate the efficacy of different dietary recommendations.

Patterns of kinship in groups of free-living sperm whales (Physeter macrocephalus) revealed by multiple molecular genetic analyses.

Mature female sperm whales (Physeter macrocephalus) live in socially cohesive groups of 10-30, which include immature animals of both sexes, and within which there is communal care of the young. We examined kinship in such groups using analyses of microsatellite DNA, mitochondrial DNA sequence, and sex-linked markers on samples of sloughed skin collected noninvasively from animals in three groups off the coast of Ecuador. Social groups were defined through photographic identification of individuals. Each group contained about 26 members, mostly female (79%). Relatedness was greater within groups, as compared to between groups. Particular mitochondrial haplotypes were characteristic of groups, but all groups contained more than one haplotype. The data are generally consistent with each group being comprised of several matrillines from which males disperse at about the age of 6 years. There are indications of paternal relatedness among grouped individuals with different mitochondrial haplotypes, suggesting long-term associations between different matrilines.

Free living astigmatid mites (Astigmatina): new taxa, rearing and use for mesostigmatid (Mesostigmata) predatory mite production

The cohort Astigmatina is divided in two major groups: Psoroptidia, composed mainly by feather and fur mites, and Non-psoroptidia, a dominant component of the acarofauna in ephemeral habitats. In these environments Astigmatina usually are saprophages or feed on fungi or bacteria. Astigmatina protonymphs undergo a complete reorganization of the body structure leading to the production of heteromorphic deutonymphs, generally specialized for dispersion through phoresy using arthropods and vertebrates as phoronts. Although most Astigmatina occur in natural environments, some species live in anthropic environments, such as food deposits, where some of them became pests; some Astigmatina infest subterraneous plant organs. Despite their economic and ecological importance, studies on the diversity and taxonomy of Astigmatina in Brazil have been rare over the last decades. The general objective of this thesis was to collaborate to the knowledge of the diversity and to evaluate the potential practical uses of these mites in Brazil. For this, new genera and species were described, method for rearing dust mites was studied and the efficiency of Astigmatina as prey for edaphic predators was evaluated. A new species of Thyreophagus (Astigmatina: Acaridae) was described based on specimens collected in Brazil, the association of three other species of this genus with stored food was reviewed and a key to all species of this genus was prepared. The genus Neotropacarus (Astigmatina: Acaridae), commonly found on plant leaves, was reviewed with the redescription of two species and description of new species collected in Brazil and from the Philippines. Two new genera and seven new species of Acaridae associated with the bee family Apidae was described and a key to Acaridae genera in subfamily Horstiinae was prepared. Several species of Astigmatina were evaluated as prey for predatory mites Stratiolaelaps scimitus (Womersley) (Mesostigmata: Laelapidae) and Protogamasellopsis zaheri Abo-Shnaf, Castilho and Moraes (Mesostigmata: Rhodacaridae), which oviposited on all evaluated astigmatids, with Tyrophagus putrescentiae (Schrank) and Aleuroglyphus ovatus (Tropeau) (Acaridae) being the most suitable prey. Seven foods and two development period, 30 and 60 days, after the introduction of 400 females of two important dust mite species, Blomia tropicalis van Bronswijk, de Cock e Oshima and Dermatophagoides pteronyssinus (Trouessart) were evaluate. With the most suitable foods, the population growth were higher than 20.2 and 15.3 for B. tropicalis and D. pteronyssinus, respectively.

Factors influencing free-living nematodes in water supplies /

"Supported by Division of Water Supply and Pollution Control U. S. Public Health Service Research Project WP-00047"

Removal of free-living nematodes by rapid sand filters /

Vita.

Interactions between ecology, demography, capture stress, and profiles of corticosterone and glucose in a free-living population of Australian freshwater crocodiles

In this study we examined three aspects pertaining to adrenocortical responsiveness in free-ranging Australian freshwater crocodiles (Crocodylus johnstoni). First, we examined the ability of freshwater crocodiles to produce corticosterone in response to a typical capture-stress protocol. A second objective addressed the relationship between capture stress, plasma glucose and corticosterone. Next we examined if variation in basal and capture-stress-induced levels of plasma corticosterone was linked to ecological or demographic factors for individuals in this free-ranging population. Blood samples obtained on three field trips were taken from a cross-sectional sample of the population. Crocodiles were bled once during four time categories at 0, 0. 5, 6, and 10 h post-capture. Plasma corticosterone increased significantly with time post-capture. Plasma glucose also significantly increased with duration of capture-stress and exhibited a positive and significant relationship with plasma corticosterone. Significant variation in basal or stress induced levels of corticosterone in crocodiles was not associated with any ecological or demographic factors including sex, age class or the year of capture that the crocodiles were sampled from. However, three immature males had basal levels of plasma corticosterone greater than 2 standard deviations above the mean. While crocodiles exhibited a pronounced, adrenocortical and hyperglycaemic response to capture stress, limited variation in adrenocortical responsiveness due to ecological and demographic factors was not evident. This feature could arise in part because this population was sampled during a period of environmental benigness. (C) 2003 Elsevier Science (USA). All rights reserved.

A simple practical method for bulk and rapid extraction of free-living nematodes from marine and estuarine sediments

A simple, rapid method is described for the extraction of large numbers of free-living nematodes from estuarine sediments. This method does not physically or chemically alter or damage the nematodes, but instead relies on their downward movement through a filtering layer of double ply tissue paper and into aerated water-filled trays. Seven trials each with 10 trays kept at 25degreesC for an initial period of 24 h yielded 3985 live nematodes l(-1) (+/-511.5 standard deviation) of estuarine sediment, free of sediment and with minimal debris. Time effects were statistically significantly different, with the same 10 trays yielding another 1259 nematodes l(-1) (+/-413.4) when kept for a second period of 24 h at the same temperature. Temperature effects were also significant, and 7 trials each with 10 trays kept for 24 h at 20-21degreesC, produced a lower yield of 2160 nematodes l(-1) (+/-532.7) of sediment. The method is expected to be of use in nematode extractions from both estuarine and marine sediments.

Individual calibration for estimating free-living walking speed using the MTI monitor

Purpose: This study was conducted to devise a new individual calibration method to enhance MTI accelerometer estimation of free-living level walking speed. Method: Five female and five male middle-aged adults walked 400 m at 3.5, 4.5, and 5.5 km(.)h(-1), and 800 in at 6.5 km(.)h(-1) on an outdoor track, following a continuous protocol. Lap speed was controlled by a global positioning system (GPS) monitor. MTI counts-to-speed calibration equations were derived for each trial, for each subject for four such trials with each of four MTI, for each subject for the average MTI. and for the pooled data. Standard errors of the estimate (SEE) with and without individual calibration were compared. To assess accuracy of prediction of free-living walking speed, subjects also completed a self-paced, brisk 3-km walk wearing one of the four MTI, and differences between actual and predicted walking speed with and without individual calibration were examined. Results: Correlations between MTI counts and walking speed were 0.90 without individual calibration, 0.98 with individual calibration for the average MTI. and 0.99 with individual calibration for a specific MTI. The SEE (mean +/- SD) was 0.58 +/- 0.30 km(.)h(-1) without individual calibration, 0.19 +/- 0.09 km h(-1) with individual calibration for the average MTI monitor, and 0.16 +/- 0.08 km(.)h(-1) with individual calibration for a specific MTI monitor. The difference between actual and predicted walking speed on the brisk 3-km walk was 0.06 +/- 0.25 km(.)h(-1) using individual calibration and 0.28 +/- 0.63 km(.)h(-1) without individual calibration (for specific accelerometers). Conclusion: MTI accuracy in predicting walking speed without individual calibration might be sufficient for population-based studies but not for intervention trials. This individual calibration method will substantially increase precision of walking speed predicted from MTI counts.

Selective disappearance of individuals with high levels of glycated haemoglobin in a free-living bird

Peer reviewed

Shaving increases daily energy expenditure in free-living root voles

Funding This study was supported by the Polish Ministry of Science and Higher Education grant NN304349335 to P.A.S. J.R.S. was supported by a 1000 talents professorship of the Chinese government.

Carriage of Staphylococcus aureus by free-living wild animals in Spain

The presence of methicillin-susceptible Staphylococcus aureus (MSSA) was analyzed in different free-living wild animals to assess the genetic diversity and predominant genotypes on each animal species. Samples were taken from the skin and/or nares, and isolates were characterized by spa typing, multilocus sequence typing (MLST) and antimicrobial susceptibility testing. The proportion of MSSA carriers were 5.00, 22.93, 19.78, and 17.67% in Eurasian griffon vulture, Iberian ibex, red deer, and wild boar, respectively (P = 0.057). A higher proportion of isolates (P = 0.000) were recovered from nasal samples (78.51%) than skin samples (21.49%), but the 9.26% of red deer and 18.25% of wild boar would have been undetected if only nasal samples had been tested. Sixty-three different spa types were identified, including 25 new spa types. The most common were t528 (43.59%) in Iberian ibex, t548 and t11212 (15.79% and 14.04%) in red deer, and t3750 (36.11%) in wild boar. By MLST, 27 STs were detected, of which 12 had not been described previously. The most frequent were ST581 for Iberian ibex (48.72%), ST425 for red deer (29.82%), and ST2328 for wild boar (42.36%). Isolates from Eurasian griffon vulture belong to ST133. Host specificity has been observed for the most frequent spa types and STs (P = 0.000). The highest resistance percentage was found against benzylpenicillin (average, 22.2%), although most of the S. aureus isolates were susceptible to all antimicrobial tested. Basically, MSSA isolates were different from those MRSA isolates previously detected in the same animal species.

Toxoplasma gondii: further studies on the subpellicular network

The association of the pellicle with cytoskeletal elements in Toxoplasma gondii allows this parasite to maintain its mechanical integrity and makes possible its gliding motility and cell invasion. The inner membrane complex (IMC) resembles the flattened membrane sacs observed in free-living protozoa and these sacs have been found to associate with cytoskeletal proteins such as articulins. We used immunofluorescence microscopy to characterise the presence and distribution of plateins, a sub-family of articulins, in T. gondii tachyzoites. A dispersed labelling of the whole protozoan body was observed. Electron microscopy of detergent-extracted cells revealed the presence of a network of 10 nm filaments distributed throughout the parasite. These filaments were labelled with anti-platein antibodies. Screening the sequenced T. gondii genome, we obtained the sequence of an IMC predicted protein with 25% identity and 42% similarity to the platein isoform alpha 1 present in Euplotes aediculatus, but with 42% identity and 55% similarity to that found in Euglena gracilis, suggesting strong resemblance to articulins.

Interaction d'Escherichia coli entérohémorragique (EHEC) avec Acanthamoeba castellanii et rôle du régulon Pho chez les EHEC

Les EHEC de sérotype O157:H7 sont des agents zoonotiques d’origine alimentaire ou hydrique. Ce sont des pathogènes émergeants qui causent chez l’humain des épidémies de gastro-entérite aiguë et parfois un syndrome hémolytique-urémique. Les EHEC réussissent leur transmission à l’humain à partir de leur portage commensal chez l’animal en passant par l’étape de survie dans l’environnement. L’endosymbiose microbienne est une des stratégies utilisées par les bactéries pathogènes pour survivre dans les environnements aquatiques. Les amibes sont des protozoaires vivants dans divers écosystèmes et connus pour abriter plusieurs agents pathogènes. Ainsi, les amibes contribueraient à transmettre les EHEC à l'humain. La première partie de mon projet de thèse est centrée sur l'interaction de l’amibe Acanthamoeba castellanii avec les EHEC. Les résultats montrent que la présence de cette amibe prolonge la persistance des EHEC, et ces dernières survivent à leur phagocytose par les amibes. Ces résultats démontrent le potentiel réel des amibes à héberger les EHEC et à contribuer à leur transmission. Cependant, l’absence de Shiga toxines améliore leur taux de survie intra-amibe. Par ailleurs, les Shiga toxines sont partiellement responsables de l’intoxication des amibes par les EHEC. Cette implication des Shiga toxines dans le taux de survie intracellulaire et dans la mortalité des amibes démontre l’intérêt d’utiliser les amibes comme modèle d'interaction hôte/pathogène pour étudier la pathogénicité des EHEC. Durant leur cycle de transmission, les EHEC rencontrent des carences en phosphate inorganique (Pi) dans l’environnement. En utilisant conjointement le système à deux composantes (TCS) PhoB-R et le système Pst (transport spécifique de Pi), les EHEC détectent et répondent à cette variation en Pi en activant le régulon Pho. La relation entre la virulence des EHEC, le PhoB-R-Pst et/ou le Pi environnemental demeure inconnue. La seconde partie de mon projet explore le rôle du régulon Pho (répondant à un stress nutritif de limitation en Pi) dans la virulence des EHEC. L’analyse transcriptomique montre que les EHEC répondent à la carence de Pi par une réaction complexe impliquant non seulement un remodelage du métabolisme général, qui est critique pour sa survie, mais aussi en coordonnant sa réponse de virulence. Dans ces conditions le régulateur PhoB contrôle directement l’expression des gènes du LEE et de l’opéron stx2AB. Ceci est confirmé par l’augmentation de la sécrétion de l’effecteur EspB et de la production et sécrétion de Stx2 en carence en Pi. Par ailleurs, l’activation du régulon Pho augmente la formation de biofilm et réduit la motilité chez les EHEC. Ceci corrèle avec l’induction des gènes régulant la production de curli et la répression de la voie de production d’indole et de biosynthèse du flagelle et du PGA (Polymère β-1,6-N-acétyle-D-glucosamine).