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A new argasid tick species (Acari: Argasidae) associated with the rock cavy, Kerodon rupestris Wied-Neuwied (Rodentia: Caviidae), in a semiarid region of Brazil
No full textAbstract\ud
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Background\ud
The rock cavy Kerodon rupestris (Wied-Neuwied, 1820) is a rodent species endemic to northeastern Brazil. Earlier studies have associated the argasid tick Ornithodoros talaje (Guérin-Méneville, 1849) with rocky cavy; however, a recent study proposed that O. talaje is not established in Brazil, where previous reports of this species were possibly misidentifications of closely related species, yet to be properly determined. Here, we describe a new species of Ornithodoros Koch, 1844 associated with rock cavies in northeastern Brazil.\ud
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Methods\ud
During 2012–2013, Ornithodoros ticks were collected from K. rupestris resting places in Paraíba State (PB) and Piauí State (PI), northeastern Brazil. These ticks were brought alive to the laboratory, and used to form two laboratory colonies (PB and PI ticks). Field-collected adults and laboratory-reared larvae were used for morphological description through light and scanning electron microscopy. DNA sequences of the mitochondrial 16S rRNA gene were generated from nymphal ticks and used to conduct phylogenetic analyses along with other Ornithodoros spp. sequences from GenBank. Reproductive compatibility of crosses between PB and PI adult ticks was evaluated, as well as analyses of hybrid ticks through larval morphology by a principal components analysis (PCA) and DNA sequences of the second internal transcribed spacer (ITS2) region from adult ticks.\ud
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Results\ud
Morphological analysis allowed recognizing these ticks as a new species, Ornithodoros rietcorreai n. sp. The larva of O. rietcorreai is distinct from those of other Ornithodoros spp. by the combination of the following character states: 14 pairs of dorsal setae, dorsal plate pyriform, hypostome with pointed apex and dental formula 3/3 anteriorly, 2/2 posteriorly, and anal valves with long and pointed leaf-shaped ends. There were a few larval morphological differences between PB and PI ticks, and their mitochondrial 16S rDNA sequences diverged by 3.3 %. On the other hand, cross-mating experiments showed that PB and PI ticks were reproductive compatible, indicating that they represent a single species. Analyses of ITS2 sequences and PCA corroborated this assumption.\ud
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Conclusion\ud
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Ornithodoros rietcorreai is described as a new species associated with K. rupestris in Brazil, increasing the Brazilian tick fauna to 70 species.This work has been approved by the Instituto Chico Mendes (ICMBio), Brazil\ud
(authorization numbers 34237–1, 36585–2), and the Ethics Committee on\ud
Research of the Universidade Federal do Vale do São Francisco, Brazil\ud
(project number 0011/161012)
Case–control study of pathogens involved in piglet diarrhea
No full textAbstract\ud
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Background\ud
Diarrhea in piglets directly affects commercial swine production. The disease results from the interaction of pathogens with the host immune system and is also affected by management procedures. Several pathogenic agents such as Campylobacter spp., Clostridium perfringens, Escherichia coli, Salmonella spp., group A rotavirus (RV-A), coronaviruses (transmissible gastroenteritis virus; porcine epidemic diarrhea virus), as well as nematode and protozoan parasites, can be associated with disease cases.\ud
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Results\ud
All bacterial, viral, protozoan, and parasitic agents here investigated, with the exception of Salmonella spp. as well as both coronaviruses, were detected in varying proportions\ud
in piglet fecal samples, and positive animals were equally distributed between case and control groups. A statistically significant difference between case and control groups was found only for Cystoisospora suis (p = 0.034) and Eimeria spp. (p = 0.047). When co-infections were evaluated, a statistically significant difference was found only for C. perfringens β2 and C. suis (p = 0.014).\ud
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Conclusions\ud
The presence of pathogens in piglets alone does not determine the occurrence of diarrhea episodes. Thus, the indiscriminate use of antibiotic and anthelminthic medication should be re-evaluated. This study also reinforces the importance of laboratory diagnosis and correct interpretation of results as well as the relevance of control and prophylactic measures.This work was supported by São Paulo Research Foundation (FAPESP)\ud
(project number 2010/00390-5 and scholarship support 2011/01563-3 and\ud
2011/19666-3)
Ticks and rickettsiae from wildlife in Belize, Central America
No full textAbstract\ud
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Background\ud
The agents of spotted fevers in Latin America are Rickettsia rickettsii, R. parkeri, Rickettsia sp. strain Atlantic rainforest, and R. massiliae. In Continental Central America, R. rickettsii remains the only known pathogenic tick-borne rickettsia. In the present study, ticks were collected from wild mammals in natural areas of Belize. Besides providing new data of ticks from Belize, we investigated rickettsial infection in some of these ticks. Our results provide ticks harboring rickettsial agents for the first time in Central America.\ud
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Methods\ud
Between 2010 and 2015, wild mammals were lived-trapped in the tropical broadleaf moist forests of central and southern Belize. Ticks were collected from the animals and identified to species by morphological and molecular analysis (DNA sequence of the tick mitochondrial 16S RNA gene). Some of the ticks were tested for rickettsial infection by molecular methods (DNA sequences of the rickettsial gltA and ompA genes).\ud
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Results\ud
A total of 84 ticks were collected from 8 individual hosts, as follows: Amblyomma pacae from 3 Cuniculus paca; Amblyomma ovale and Amblyomma coelebs from a Nasua narica; A. ovale from an Eira Barbara; A. ovale, Amblyomma cf. oblongoguttatum, and Ixodes affinis from a Puma concolor; and A. ovale, A. coelebs, A. cf. oblongoguttatum, and I. affinis from two Panthera onca. Three rickettsial agents were detected: Rickettsia amblyommii in A. pacae, Rickettsia sp. strain Atlantic rainforest in A. ovale, and Rickettsia sp. endosymbiont in Ixodes affinis.\ud
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Conclusions\ud
The present study provides unprecedented records of ticks harboring rickettsial agents in the New World. An emerging rickettsial pathogen of South America, Rickettsia sp. strain Atlantic rainforest, is reported for the first time in Central America. Besides expanding the distribution of 3 rickettsial agents in Central America, our results highlight the possible occurrence of Rickettsia sp. strain Atlantic rainforest-caused spotted fever human cases in Belize, since its possible vector, A. ovale, is recognized as one of the most important human-biting ticks in the Neotropical region.This work was supported by Fundação de Amparo a Pesquisa do Estado de\ud
São Paulo (FAPESP) and Coordenação de Aperfeiçoamento de Pessoal de\ud
Nível Superior (CAPES), Brazil. Field-work was funded by the UK Darwin\ud
Initiative and Panther
The phylogeography of trypanosomes from South American alligatorids and African crocodilids is consistent with the geological history of South American river basins and the transoceanic dispersal of Crocodylus at the Miocene
No full textAbstract
Background
Little is known about the diversity, phylogenetic relationships, and biogeography of trypanosomes infecting non-mammalian hosts. In this study, we investigated the influence of host species and biogeography on shaping the genetic diversity, phylogenetic relationship, and distribution of trypanosomes from South American alligatorids and African crocodilids.
Methods
Small Subunit rRNA (SSU rRNA) and glycosomal Glyceraldehyde Phosphate Dehydrogenase (gGAPDH) genes were employed for phylogenetic inferences. Trypanosomes from crocodilians were obtained by haemoculturing. Growth behaviour, morphology, and ultrastructural features complement the molecular description of two new species strongly supported by phylogenetic analyses.
Results
The inferred phylogenies disclosed a strongly supported crocodilian-restricted clade comprising three subclades. The subclade T. grayi comprised the African Trypanosoma grayi from Crocodylus niloticus and tsetse flies. The subclade T. ralphi comprised alligatorid trypanosomes represented by Trypanosoma ralphi n. sp. from Melanosuchus niger, Caiman crocodilus and Caiman yacare from Brazilian river basins. T. grayi and T. ralphi were sister subclades. The basal subclade T. terena comprised alligatorid trypanosomes represented by Trypanosoma terena n. sp. from Ca. yacare sharing hosts and basins with the distantly genetic related T. ralphi. This subclade also included the trypanosome from Ca. crocodilus from the Orinoco basin in Venezuela and, unexpectedly, a trypanosome from the African crocodilian Osteolaemus tetraspis.
Conclusion
The close relationship between South American and African trypanosomes is consistent with paleontological evidence of recent transoceanic dispersal of Crocodylus at the Miocene/Pliocene boundaries (4–5 mya), and host-switching of trypanosomes throughout the geological configuration of South American hydrographical basins shaping the evolutionary histories of the crocodilians and their trypanosomes
Existence of a potential neurogenic system in the adult human brain
No full textAbstract
Background
Prevailingly, adult mammalian neurogenesis is thought to occur in discrete, separate locations known as neurogenic niches that are best characterized in the subgranular zone (SGZ) of the dentate gyrus and in the subventricular zone (SVZ). The existence of adult human neurogenic niches is controversial.
Methods
The existence of neurogenic niches was investigated with neurogenesis marker immunostaining in histologically normal human brains obtained from autopsies. Twenty-eight adult temporal lobes, specimens from limbic structures and the hypothalamus of one newborn and one adult were examined.
Results
The neural stem cell marker nestin stained circumventricular organ cells and the immature neuronal marker doublecortin (DCX) stained hypothalamic and limbic structures adjacent to circumventricular organs; both markers stained a continuous structure running from the hypothalamus to the hippocampus. The cell proliferation marker Ki-67 was detected predominately in structures that form the septo-hypothalamic continuum. Nestin-expressing cells were located in the fimbria-fornix at the insertion of the choroid plexus; ependymal cells in this structure expressed the putative neural stem cell marker CD133. From the choroidal fissure in the temporal lobe, a nestin-positive cell layer spread throughout the SVZ and subpial zone. In the subpial zone, a branch of this layer reached the hippocampal sulcus and ended in the SGZ (principally in the newborn) and in the subiculum (principally in the adults). Another branch of the nestin-positive cell layer in the subpial zone returned to the optic chiasm. DCX staining was detected in the periventricular and middle hypothalamus and more densely from the mammillary body to the subiculum through the fimbria-fornix, thus running through the principal neuronal pathway from the hippocampus to the hypothalamus. The column of the fornix forms part of this pathway and appears to coincide with the zone previously identified as the human rostral migratory stream. Partial co-labeling with DCX and the neuronal marker βIII-tubulin was also observed.
Conclusions
Collectively, these findings suggest the existence of an adult human neurogenic system that rises from the circumventricular organs and follows, at minimum, the circuitry of the hypothalamus and limbic system
Comparative study of equine mesenchymal stem cells from healthy and injured synovial tissues: an in vitro assessment
No full textAbstract\ud
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Background\ud
Bone marrow and adipose tissues are known sources of mesenchymal stem cells (MSCs) in horses; however, synovial tissues might be a promising alternative. The aim of this study was to evaluate phenotypic characteristics and differentiation potential of equine MSCs from synovial fluid (SF) and synovial membrane (SM) of healthy joints (SF-H and SM-H), joints with osteoarthritis (SF-OA and SM-OA) and joints with osteochondritis dissecans (SF-OCD and SM-OCD) to determine the most suitable synovial source for an allogeneic therapy cell bank.\ud
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Methods\ud
Expression of the markers CD90, CD105, CD44, and CD34 in SF-H, SM-H, SF-OA, SM-OA, SF-OCD and SM-OCD was verified by flow cytometry, and expression of cytokeratin, vimentin, PGP 9.5, PCNA, lysozyme, nanog, and Oct4 was verified by immunocytochemistry. MSCs were cultured and evaluated for their chondrogenic, osteogenic and adipogenic differentiation potential. Final quantification of extracellular matrix and mineralized matrix was determined using AxioVision software. A tumorigenicity test was conducted in Balb-Cnu/nu mice to verify the safety of the MSCs from these sources.\ud
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Results\ud
Cultured cells from SF and SM exhibited fibroblastoid morphology and the ability to adhere to plastic. The time elapsed between primary culture and the third passage was approximately 73 days for SF-H, 89 days for SF-OCD, 60 days for SF-OA, 68 days for SM-H, 57 days for SM-OCD and 54 days for SM-OA. The doubling time for SF-OCD was higher than that for other cells at the first passage (P < 0.05). MSCs from synovial tissues showed positive expression of the markers CD90, CD44, lysozyme, PGP 9.5, PCNA and vimentin and were able to differentiate into chondrogenic (21 days) and osteogenic (21 days) lineages, and, although poorly, into adipogenic lineages (14 days). The areas staining positive for extracellular matrix in the SF-H and SM-H groups were larger than those in the SF-OA and SM-OA groups (P < 0.05). The positive mineralized matrix area in the SF-H group was larger than those in all the other groups (P < 0.05). The studied cells exhibited no tumorigenic effects.\ud
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Conclusions\ud
SF and SM are viable sources of equine MSCs. All sources studied provide suitable MSCs for an allogeneic therapy cell bank; nevertheless, MSCs from healthy joints may be preferable for cell banking purposes because they exhibit better chondrogenic differentiation capacity.This research was supported by Fundação Coordenação de Aperfeiçoamento\ud
de Pessoal de Nível Superior (CAPES), Brasília, SP, Brazil, and by Fundação de\ud
Amparo à Pesquisa do Estado de São Paulo (FAPESP), São Paulo, SP, Brazil.\ud
These sponsors did not have any influence on the study design, on the\ud
collection, analysis and interpretation of data, or on the writing of the\ud
manuscript and decision to submit for publication
Genome-wide association between single nucleotide polymorphisms with beef fatty acid profile in Nellore cattle using the single step procedure
No full textAbstract\ud
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Background\ud
Saturated fatty acids can be detrimental to human health and have received considerable attention in recent years. Several studies using taurine breeds showed the existence of genetic variability and thus the possibility of genetic improvement of the fatty acid profile in beef. This study identified the regions of the genome associated with saturated, mono- and polyunsaturated fatty acids, and n-6 to n-3 ratios in the Longissimus thoracis of Nellore finished in feedlot, using the single-step method.\ud
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Results\ud
The results showed that 115 windows explain more than 1 % of the additive genetic variance for the 22 studied fatty acids. Thirty-one genomic regions that explain more than 1 % of the additive genetic variance were observed for total saturated fatty acids, C12:0, C14:0, C16:0 and C18:0. Nineteen genomic regions, distributed in sixteen different chromosomes accounted for more than 1 % of the additive genetic variance for the monounsaturated fatty acids, such as the sum of monounsaturated fatty acids, C14:1 cis-9, C18:1 trans-11, C18:1 cis-9, and C18:1 trans-9. Forty genomic regions explained more than 1 % of the additive variance for the polyunsaturated fatty acids group, which are related to the total polyunsaturated fatty acids, C20:4 n-6, C18:2 cis-9 cis12 n-6, C18:3 n-3, C18:3 n-6, C22:6 n-3 and C20:3 n-6 cis-8 cis-11 cis-14. Twenty-one genomic regions accounted for more than 1 % of the genetic variance for the group of omega-3, omega-6 and the n-6:n-3 ratio.\ud
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Conclusions\ud
The identification of such regions and the respective candidate genes, such as ELOVL5, ESSRG, PCYT1A and genes of the ABC group (ABC5, ABC6 and ABC10), should contribute to form a genetic basis of the fatty acid profile of Nellore (Bos indicus) beef, contributing to better selection of the traits associated with improving human health.MVA Lemos, (FAPESP, Fundação de Amparo à Pesquisa do Estado de São\ud
Paulo). HLJ Chiaia, MP Berton, FLB Feitosa received scholarships from the\ud
Coordination Office for Advancement of University-level Personnel (CAPES;\ud
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior) in conjunction\ud
with the Postgraduate Program on Genetics and Animal Breeding, Faculdade\ud
de Ciências Agrárias e Veterinárias, Universidade Estadual Paulista (FCAV,\ud
UNESP). F Baldi (FAPESP, Fundação de Amparo à Pesquisa do Estado de São\ud
Paulo grant #2011/21241-0). Lucia G. Albuquerque (FAPESP, Fundação de\ud
Amparo à Pesquisa do Estado de São Paulo grant #2009/16118-5)
Flash sintering of ionic conductors: the need of a reversible electrochemical reaction
No full textFlash sintering (FS) is a current-assisted sintering technique able to densify ceramics in short periods of time (just a few seconds) at temperatures significantly lower than in conventional sintering processes. FS technique was firstly reported for yttrium-stabilized zirconia and later it had been proved successful for a large range of oxide materials that present ionic conduction by oxygen vacancies. This paper describes the use of FS on a sodium ion conductor based on a model compound, the beta-alumina. Different electrode materials have been tested, i.e., silver and platinum. The impact of the electrode reaction on the current flow, and thus, on the sintering efficiency is shown for the first time. It appears that the densification by FS can only be possible if the current collectors, i.e., the electrodes, are specifically designed to enable reversible electrochemical reactions at the interfaces between the electrodes and the ionic compound, insuring the current flow through the powder compact.CAPE
Association between work ability and fatigue in Brazilian nursing workers
No full textBACKGROUND: Impaired work ability is associated with work-related illnesses, early retirement and rising pension costs.\ud
OBJECTIVE: To investigate the association between work ability and fatigue in nursing workers.\ud
METHODS: Cross-sectional study conducted with 100 nursing workers from two inpatient units at a public teaching hospital in Sao Paulo, Brazil. The data were collected by means of a socio-demographic profile questionnaire, Work Ability Index (WAI) and Chalder Fatigue Scale. The data were analyzed by means of descriptive and analytical statistical methods, tests of association and multiple linear regression.\ud
RESULTS: The study population was mainly composed of women (88%), exhibited a high educational level (76%), average age 39.4 years old (SD = 9.5) and 15 years of professional experience, on average. The average score on WAI was good (39.4 points,\ud
SD = 6.0) but surprisingly, 35% of the participants exhibited moderate to poor work ability. Fatigue was found in 52% of the participants. The score onWAI decreased in association with fatigue (p < 0.001) and longer length of work in the same workplace\ud
(p = 0.001), as well as among nursing technicians compared to nurses (p = 0.040).\ud
CONCLUSIONS: Fatigue, longer length of work in the same workplace and work category nursing technician were associated with decreased work ability, which emphasizes the need for investment in health and quality of work life
Automatic identification of drop-down menu widgets using mutation observers and visibility changes
No full textDrop-down Menus are JavaScript/CSS based Widget implementations which frequently represent the main navigation mechanism of a web application. These Widgets are used to display sub-level navigation links which are presented only as users position the mouse over the Widget. However many of the Widgets available on theWeb do not implement Accessible Rich Internet Applications (ARIA) requirements which address how to make these Widgets accessible. This paper presents an automatic approach for identifying these Drop-down Menu Widgets in web applications. The automatic identification of these Widgets works towards the implementation of ARIA automatic evaluation tools to assist web developers while developing accessible Widgets. The proposed approach was implemented in a tool called aria-check-menus which is open-source available. The tool was evaluated through a case study and the results showed evidences that the proposed approach is capable of automatically identifying Drop-down Menu Widgets in web applications, having correctly identified 146 Drop-down Menus Widgets in high traffic websites with 0.77 precision and 0.90 recall in average. Henceforth, the tool could be used in an automatic ARIA evaluation tool to support web developers in the implementation of accessible Drop-down menu Widgets.CNPqCAPESFAPES