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151.
152.
Natalie Olifiers Ana Maria Jansen Heitor Miraglia Herrera Rita de Cassia Bianchi Paulo Sergio D’Andrea Guilherme de Miranda Mour?o Matthew Edzart Gompper 《PloS one》2015,10(12)
Wild animals are infected by diverse parasites, but how they influence host health is poorly understood. We examined the relationship of trypanosomatids and gastrointestinal parasites with health of wild brown-nosed coatis (Nasua nasua) from the Brazilian Pantanal. We used coati body condition and hematological parameters as response variables in linear models that were compared using an information theoretic approach. Predictors were high/low parasitemias by Trypanosoma cruzi and T. evansi, and indices representing the abundance of distinct groups of gastrointestinal parasites. We also analyzed how host health changed with host sex and reproductive seasonality. Hemoparasites was best related to coati body condition and hematological indices, whereas abundance of gastrointestinal parasites was relatively less associated with coati health. Additionally, some associations were best predicted by models that incorporated reproductive seasonality and host sex. Overall, we observed a lower health condition during the breeding season, when coatis are under reproductive stress and may be less able to handle infection. In addition, females seem to handle infection better than males. Body condition was lower in coatis with high parasitemias of T. evansi, especially during the reproductive season. Total red blood cell counts, packed cell volume, platelets and eosinophils were also lower in animals with high T. evansi parasitemias. Total white blood cell counts and mature neutrophils were lower in animals with high parasitemias for both Trypanosoma species, with neutrophils decreasing mainly during the reproductive season. Overall, decreases in hematological parameters of females with T. evansi high parasitemias were less evident. For T. cruzi, monocytes decreased in individuals with high parasitemias. High abundances of microfilariae in the bloodstream, and cestode eggs and coccidian oocysts in feces were also associated with coati blood parameters. This study shows the potential value of examining hematological parameters as an approach to better understand the ecological relevance of parasite-host interactions. 相似文献
153.
Fernanda Abreu Viviana Morillo Fabrícia F Nascimento Clarissa Werneck Mauricio Egidio Cant?o Luciane Prioli Ciapina Luiz Gonzaga Paula de Almeida Christopher T Lefèvre Dennis A Bazylinski Ana Tereza Ribeiro de Vasconcelos Ulysses Lins 《The ISME journal》2014,8(5):1055-1068
Candidatus Magnetoglobus multicellularis (Ca. M. multicellularis) is a member of a group of uncultured magnetotactic prokaryotes that possesses a unique multicellular morphology. To better understand this organism''s physiology, we used a genomic approach through pyrosequencing. Genomic data analysis corroborates previous structural studies and reveals the proteins that are likely involved in multicellular morphogenesis of this microorganism. Interestingly, some detected protein sequences that might be involved in cell adhesion are homologues to phylogenetically unrelated filamentous multicellular bacteria proteins, suggesting their contribution in the early development of multicellular organization in Bacteria. Genes related to the behavior of Ca. M. multicellularis (chemo-, photo- and magnetotaxis) and its metabolic capabilities were analyzed. On the basis of the genomic–physiologic information, enrichment media were tested. One medium supported chemoorganoheterotrophic growth of Ca. M. multicellularis and allowed the microorganisms to maintain their multicellular morphology and cell cycle, confirming for the first time that the entire life cycle of the MMP occurs in a multicellular form. Because Ca. M. multicellularis has a unique multicellular life style, its cultivation is an important achievement for further studies regarding the multicellular evolution in prokaryotes. 相似文献
154.
André Rodrigues de Souza Carlos Alberto Mour?o Júnior Fabio Santos do Nascimento José Lino-Neto 《PloS one》2014,9(5)
Sexually selected signals are common in many animals, though little reported in social insects. We investigated the occurrence of male visual signals mediating the dominance relationships among males and female choice of sexual partner in the paper wasp Polistes simillimus. Males have three conspicuous, variable and sexually dimorphic traits: black pigmentation on the head, a pair of yellow abdominal spots and body size differences. By conducting behavioral assays, we found that none of the three visual traits are associated with male-male dominance relationship. However, males with higher proportion of black facial pigmentation and bigger yellow abdominal spots are more likely chosen as sexual partners. Also, after experimentally manipulating the proportion of black pigment on males'' face, we found that females may evaluate male facial coloration during the choice of a sexual partner. Thus, the black pigmentation on P. simillimus male''s head appears to play a role as a sexually selected visual signal. We suggest that sexual selection is a common force in Polistes and we highlight the importance of this group as a model for the study of visual communication in insects. 相似文献
155.
Sofia Ribeiro Joana Mourão Ângela Novais Joana Campos Luísa Peixe Patrícia Antunes 《Environmental microbiology》2021,23(12):7563-7577
Expansion of mcr-carrying Enterobacteriaceae (MCR-E) is a well-recognized problem affecting animals, humans and the environment. Ongoing global control actions involve colistin restrictions among food-animal production, but their impact on poultry-derived products is largely unknown, justifying comprehensive farm-to-fork studies. Occurrence of MCR-E among 53 chicken-meat batches supplied from 29 Portuguese farms shortly after colistin withdrawal was evaluated. Strains (FT-IR/MLST/WGS), mcr plasmids and their adaptive features were characterized by cultural, molecular and genomic approaches. We found high rates of chicken-meat batches (80%–100% – 4 months; 12% – the last month) with multiple MDR + mcr-1-carrying Escherichia coli (Ec-including ST117 and ST648-Cplx) and Klebsiella pneumoniae (Kp-ST147-O5:K35) clones, some of them persisting over time. The mcr-1 was located in the chromosome (Ec-ST297/16-farms) or dispersed IncX4 (Ec-ST602/ST6469/5-farms), IncHI2-ST2/ST4 (Ec-ST533/ST6469/5 farms and Kp-ST147/6-farms) or IncI2 (Ec-ST117/1-farm) plasmids. WGS revealed high load and diversity in virulence, antibiotic resistance and metal tolerance genes. This study supports colistin withdrawal potential efficacy in poultry production and highlights both poultry-production chain as a source of mcr-1 and the risk of foodborne transmission to poultry-meat consumers. Finally, in the antibiotic reduction/replacement context, other potential co-selective pressures (e.g., metals-Cu as feed additives) need to be further understood to guide concerted, effective and durable actions under 'One Health' perspective. 相似文献
156.
Brandi J Oliveira ÉC Monteiro N Vasconcelos AF Dekker RF Barbosa AM Silveira JL Mourão PA Corradi da Silva Mde L 《Journal of microbiology and biotechnology》2011,21(10):1036-1042
The exopolysaccharide botryosphaeran (EPS(GLC); a (1--> 3)(1-->6)-β-D-glucan from Botryosphaeria rhodina MAMB- 05) was sulfonated to produce a water-soluble fraction (EPS(GLC)-S) using pyridine and chlorosulfonic acid in formamid. This procedure was then repeated twice to produce another fraction (EPSGLC-RS) with a higher degree of substitution (DS, 1.64). The purity of each botryosphaeran sample (unsulfonated and sulfonated) was assessed by gel filtration chromatography (Sepharose CL-4B), where each polysaccharide was eluted as a single symmetrical peak. The structures of the sulfonated and re-sulfonated botryosphaerans were investigated using ultraviolet-visible (UV-Vis), Fourier-transform infrared (FT-IR), and (13)C nuclear magnetic resonance ((13)C NMR) spectroscopies. EPS(GLC) and EPS(GLC)-RS were also assayed for anticoagulation activity, and EPS(GLC)-RS was identified as an anticoagulant. 相似文献
157.
Luciane Aparecida Pascucci Sande de Souza Mônica de Biagi Curtarelli Mukul Mukherjee Valdeci Carlos DionisioAuthor vitae 《Journal of electromyography and kinesiology》2011,21(5):719-726
The aim of this study was to explore the electromyographic, kinetic and kinematic patterns during a partially restricted sit-to-stand task in subjects with and without Parkinson’s disease (PD). If the trunk is partially restricted, different behavior of torques and muscle activities could be found and it can serve as a reference of the deterioration in the motor performance of subjects with PD. Fifteen subjects participated in this study and electromyography (EMG) activity of the tibialis anterior (TA), soleus (SO), vastus medialis oblique (VMO), biceps femoris (BF) and erector spinae (ES) were recorded and biomechanical variables were calculated during four phases of the movement. Subjects with PD showed more flexion at the ankle, knee and hip joints and increased knee and hip joint torques in comparison to healthy subjects in the final position. However, these joint torques can be explained by the differences in kinematic data. Also, the hip, knee and ankle joint torques were not different in the acceleration phase of movement. The use of a partially restricted sit-to-stand task in PD subjects with moderate involvement leads to the generation of joint torques similar to healthy subjects. This may have important implications for rehabilitation training in PD subjects. 相似文献
158.
Gamer LW Tsuji K Cox K Capelo LP Lowery J Beppu H Rosen V 《Genesis (New York, N.Y. : 2000)》2011,49(9):719-724
Initiation of BMP signaling is dependent upon activation of Type I BMP receptor by constitutively active Type II BMP receptor. Three Type II BMP receptors have been identified; Acvr2a and Acvr2b serve as receptors for BMPs and for activin-like ligands whereas BMPR-II functions only as a BMP receptor. As BMP signaling is required for endochondral ossification and loss of either Acvr2a or Acvr2b is not associated with deficits in limb development, we hypothesized that BMPR-II would be essential for BMP signaling during skeletogenesis. We removed BMPR-II from early limb mesoderm by crossing BMPR-II floxed mice with those carrying the Prx1-Cre transgene. Mice lacking limb expression of BMPR-II have normal skeletons that could not be distinguished from control littermates. From these data, we conclude that BMPR-II is not required for endochondral ossification in the limb where loss of BMPR-II may be compensated by BMP utilization of Acvr2a and Acvr2b. 相似文献
159.
de Andrade AC Luz PM Velasque L Veloso VG Moreira RI Russomano F Chicarino-Coelho J Pires E Levi JE Grinsztejn B Friedman RK 《PloS one》2011,6(3):e18297
Introduction
Despite the availability of preventive strategies (screening tests and vaccines), cervical cancer continues to impose a significant health burden in low- and medium-resourced countries. HIV-infected women are at increased risk for infection with human papillomavirus (HPV) and thus development of cervical squamous intraepithelial neoplasia (CIN).Methods
Study participants included HIV-infected women enrolling the prospective open cohort of Evandro Chagas Clinical Research Institute, Oswaldo Cruz Foundation (IPEC/FIOCRUZ). At cohort entry, women were subjected to conventional Papanicolaou test, HPV-DNA test and colposcopy; lesions suspicious for CIN were biopsied. Histopathology report was based on directed biopsy or on specimens obtained by excision of the transformation zone or cervical conization. Poisson regression modeling was used to assess factors associated with CIN2+ diagnosis.Results
The median age of the 366 HIV-infected women included in the study was 34 years (interquartile range: 28–41 years). The prevalence of CIN1, CIN2 and CIN3 were 20.0%, 3.5%, and 2.2%, respectively. One woman was found to have cervical cancer. The prevalence of CIN2+ was 6.0%. Factors associated with CIN2+ diagnosis in the multivariate model were age < years compared to ≥35 years (aPR = 3.22 95%CI 1.23–8.39), current tobacco use (aPR = 3.69 95%CI 1.54–8.78), nadir CD4 T-cell count <350 cells/mm3 when compared to ≥ 350 cells/mm3 (aPR = 6.03 95%CI 1.50–24.3) and concomitant diagnosis of vulvar and/or vaginal intraepithelial lesion (aPR = 2.68 95%CI 0.99–7.24).Discussion
Increased survival through wide-spread use of highly active antiretroviral therapy might allow for the development of cervical cancer. In Brazil, limited cytology screening and gynecological care adds further complexity to the HIV-HPV co-infection problem. Integrated HIV care and cervical cancer prevention programs are needed for the prevention of cervical cancer mortality in this group of women. 相似文献160.
Itiane Diehl de Franceschi Elenara Rieger Alessandra Pinto Vargas Denise Bertin Rojas Aline Guimarães Campos Virginia Cielo Rech Luciane Rosa Feksa Clóvis Milton Duval Wannmacher 《Neurochemical research》2013,38(3):632-643
Maple Syrup Urine Disease is an inborn error of metabolism caused by severe deficiency in the activity of branched-chain α-keto acid dehydrogenase complex. Neurological disorder is common in patients with maple syrup urine disease. Although leucine is considered the main toxic metabolite, the mechanisms underlying the neuropathology of brain injury are poorly understood. In the present study, we evaluated the possible preventive effect of the co-administration of creatine plus pyruvate on the effects elicited by leucine administration to female Wistar rats during pregnancy and lactation on some oxidative stress parameters as well as the activities of some enzymes involved in the phosphoryltransfer network in the brain cortex and hippocampus of the offspring at 21 days of age. Leucine administration induced oxidative stress and altered the activities of pyruvate kinase, adenylate kinase, mitochondrial and cytosolic creatine kinase. Co-administration of creatine plus pyruvate was partially effective in the prevention of some alterations provoked by leucine administration on the oxidative stress but not in the enzymes of phosphoryltransfer network. These results suggest that non-treated maternal hyperleucinemia may be toxic to the brain of the offspring. 相似文献