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1.
Nature ; 507(7490): 90-3, 2014 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-24429523

RESUMO

Forests are major components of the global carbon cycle, providing substantial feedback to atmospheric greenhouse gas concentrations. Our ability to understand and predict changes in the forest carbon cycle--particularly net primary productivity and carbon storage--increasingly relies on models that represent biological processes across several scales of biological organization, from tree leaves to forest stands. Yet, despite advances in our understanding of productivity at the scales of leaves and stands, no consensus exists about the nature of productivity at the scale of the individual tree, in part because we lack a broad empirical assessment of whether rates of absolute tree mass growth (and thus carbon accumulation) decrease, remain constant, or increase as trees increase in size and age. Here we present a global analysis of 403 tropical and temperate tree species, showing that for most species mass growth rate increases continuously with tree size. Thus, large, old trees do not act simply as senescent carbon reservoirs but actively fix large amounts of carbon compared to smaller trees; at the extreme, a single big tree can add the same amount of carbon to the forest within a year as is contained in an entire mid-sized tree. The apparent paradoxes of individual tree growth increasing with tree size despite declining leaf-level and stand-level productivity can be explained, respectively, by increases in a tree's total leaf area that outpace declines in productivity per unit of leaf area and, among other factors, age-related reductions in population density. Our results resolve conflicting assumptions about the nature of tree growth, inform efforts to undertand and model forest carbon dynamics, and have additional implications for theories of resource allocation and plant senescence.


Assuntos
Tamanho Corporal , Ciclo do Carbono , Carbono/metabolismo , Árvores/anatomia & histologia , Árvores/metabolismo , Envelhecimento/metabolismo , Biomassa , Clima , Geografia , Modelos Biológicos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Tamanho da Amostra , Especificidade da Espécie , Fatores de Tempo , Árvores/classificação , Árvores/crescimento & desenvolvimento , Clima Tropical
2.
J Helminthol ; 97: e1, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36606516
3.
Eur J Vasc Endovasc Surg ; 54(2): 212-219, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28625356

RESUMO

OBJECTIVES: The aim was to investigate whether cardiopulmonary exercise testing (CPET) variables derived from cycle and arm ergonometry correlate, and whether CPET variables and pre-operative N-terminal pro-brain natriuretic peptide (NT-proBNP) have prognostic significance and if the combination of the two has incremental value. METHODS: A prospective observational pilot study was conducted; 70 patients who underwent infra-inguinal bypass surgery were recruited. Pre-operatively subjects underwent CPET with both arm and leg ergonometry, to measure peak oxygen consumption, anaerobic threshold (AT), and ventilatory equivalents. In addition pre-operative serum samples of NT-proBNP were obtained. The primary endpoint was 1 year all-cause mortality; in addition, data were collected on complications, morbidity, length of stay, and major adverse cardiac events (MACE). RESULTS: The 1 year mortality rate was 6%, the overall complications rate was 23%, and the combined incidence of MACE and 1 year mortality was 10%. Cycle ergonometry peak VO2 14 mL/kg/min (RR 5.5, 95% CI 1.4-22.4, p = .007) and AT < 10mL/kg/min (RR 3.0, 95% CI 1.1-7.0, p = .03) were predictors of post-operative complications. Pre-operative NT-proBNP > 320 ng/L (RR 18, 95% CI 2.5-140 p = .0003) was the sole predictor of 1 year mortality or MACE. CONCLUSION: The measurement of pre-operative NT-proBNP in peripheral vascular disease patients undergoing infra-inguinal bypass can predict 1 year mortality and MACE. CPET variables from cycle ergonometry are predictors of post-operative complications in this patient group.


Assuntos
Teste de Esforço , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Doença Arterial Periférica/cirurgia , Enxerto Vascular , Idoso , Limiar Anaeróbio , Biomarcadores/sangue , Distribuição de Qui-Quadrado , Feminino , Humanos , Estimativa de Kaplan-Meier , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Razão de Chances , Consumo de Oxigênio , Doença Arterial Periférica/sangue , Doença Arterial Periférica/diagnóstico , Doença Arterial Periférica/fisiopatologia , Projetos Piloto , Valor Preditivo dos Testes , Estudos Prospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Enxerto Vascular/efeitos adversos , Enxerto Vascular/mortalidade
5.
Psychol Med ; 46(1): 73-85, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26315278

RESUMO

BACKGROUND: Generalized anxiety disorder (GAD) and panic disorder (PD) differ in their biology and co-morbidities. We hypothesized that GAD but not PD symptoms at the age of 15 years are associated with depression diagnosis at 18 years. METHOD: Using longitudinal data from the Avon Longitudinal Study of Parents and Children (ALSPAC) birth cohort we examined relationships of GAD and PD symptoms (measured by the Development and Well-Being Assessment) at 15 years with depression at 18 years (by the Clinical Interview Schedule - Revised) using logistic regression. We excluded adolescents already depressed at 15 years and adjusted for social class, maternal education, birth order, gender, alcohol intake and smoking. We repeated these analyses following multiple imputation for missing data. RESULTS: In the sample with complete data (n = 2835), high and moderate GAD symptoms in adolescents not depressed at 15 years were associated with increased risk of depression at 18 years both in unadjusted analyses and adjusting for PD symptoms at 15 years and the above potential confounders. The adjusted odds ratio (OR) for depression at 18 years in adolescents with high relative to low GAD scores was 5.2 [95% confidence interval (CI) 3.0-9.1, overall p < 0.0001]. There were no associations between PD symptoms and depression at 18 years in any model (high relative to low PD scores, adjusted OR = 1.3, 95% CI 0.3-4.8, overall p = 0.737). Missing data imputation strengthened the relationship of GAD symptoms with depression (high relative to low GAD scores, OR = 6.2, 95% CI 3.9-9.9) but those for PD became weaker. CONCLUSIONS: Symptoms of GAD but not PD at 15 years are associated with depression at 18 years. Clinicians should be aware that adolescents with GAD symptoms may develop depression.


Assuntos
Transtornos de Ansiedade/epidemiologia , Transtorno Depressivo/epidemiologia , Transtorno de Pânico/epidemiologia , Adolescente , Comorbidade , Inglaterra/epidemiologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Risco
6.
Fish Shellfish Immunol ; 49: 427-35, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26672904

RESUMO

The growth performance, immunological status, intestinal morphology and microbiology of tilapia, Oreochromis niloticus, were investigated after dietary administration of the commercial probiotic AquaStar(®) Growout. Tilapia (29.02 ± 0.33 g) were split into five treatments; control (CON), 1.5 g kg(-1) probiotic (PRO-1.5), 3 g kg(-1) probiotic (PRO-3), pulsed probiotic feeding (PRO-PULSE) or an initial probiotic feed followed by control feeding (PRO-INI). After six weeks of experimental feeding, fish fed PRO-3 displayed significantly higher final weight, weight gain and SGR compared to the CON or PRO-INI treatments. Supplementation of the probiotic at this dose induced an up-regulation of intestinal caspase-3, PCNA and HSP70 mRNA levels compared to the CON fed fish. Immuno-modulatory pathways were also affected; significantly higher expression of TLR2, pro-inflammatory genes TNFα and IL-1ß, and anti-inflammatory genes IL-10 and TGFß suggest that the probiotic may potentiate a higher state of mucosal tolerance and immuno-readiness. Histological appraisal revealed significantly higher numbers of intraepithelial leucocytes in the intestine of PRO-3 fed fish compared with treatments CON, PRO-PULSE and PRO-INI but not PRO-1.5. Additionally, fish receiving PRO-3 had a significantly higher abundance of goblet cells in their mid-intestine when compared with fish from all other treatments. Together, these data suggest that continuous provision of AquaStar(®) Growout at 3 g kg(-1) can improve tilapia growth and elevate the intestinal immunological status of the host.


Assuntos
Ciclídeos/crescimento & desenvolvimento , Ciclídeos/imunologia , Microbioma Gastrointestinal/imunologia , Intestinos/imunologia , Probióticos , Ração Animal/análise , Animais , Ciclídeos/genética , Dieta/veterinária , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Intestinos/microbiologia , Distribuição Aleatória , Regulação para Cima
7.
Oecologia ; 182(2): 547-57, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27337965

RESUMO

While the importance of local-scale habitat niches in shaping tree species turnover along environmental gradients in tropical forests is well appreciated, relatively little is known about the influence of phylogenetic signal in species' habitat niches in shaping local community structure. We used detailed maps of the soil resource and topographic variation within eight 24-50 ha tropical forest plots combined with species phylogenies created from the APG III phylogeny to examine how phylogenetic beta diversity (indicating the degree of phylogenetic similarity of two communities) was related to environmental gradients within tropical tree communities. Using distance-based redundancy analysis we found that phylogenetic beta diversity, expressed as either nearest neighbor distance or mean pairwise distance, was significantly related to both soil and topographic variation in all study sites. In general, more phylogenetic beta diversity within a forest plot was explained by environmental variables this was expressed as nearest neighbor distance versus mean pairwise distance (3.0-10.3 % and 0.4-8.8 % of variation explained among plots, respectively), and more variation was explained by soil resource variables than topographic variables using either phylogenetic beta diversity metric. We also found that patterns of phylogenetic beta diversity expressed as nearest neighbor distance were consistent with previously observed patterns of niche similarity among congeneric species pairs in these plots. These results indicate the importance of phylogenetic signal in local habitat niches in shaping the phylogenetic structure of tropical tree communities, especially at the level of close phylogenetic neighbors, where similarity in habitat niches is most strongly preserved.


Assuntos
Filogenia , Clima Tropical , Ecossistema , Florestas , Solo/química , Árvores
8.
Heredity (Edinb) ; 115(2): 125-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24105437

RESUMO

In forests with gap disturbance regimes, pioneer tree regeneration is typically abundant following stand-replacing disturbances, whether natural or anthropogenic. Differences in pioneer tree density linked to disturbance regime can influence pollinator behaviour and impact on mating patterns and genetic diversity of pioneer populations. Such mating pattern shifts can manifest as higher selfing rates and lower pollen diversity in old growth forest populations. In secondary forest, where more closely related pollen donors occur, an increase in biparental inbreeding is a potential problem. Here, we investigate the consequences of secondary forest colonisation on the mating patterns and genetic diversity of open-pollinated progeny arrays for the long-lived, self-compatible pioneer tree, Vochysia ferruginea, at two Costa Rican sites. Five microsatellite loci were screened across adult and seed cohorts from old growth forest with lower density, secondary forest with higher density, and isolated individual trees in pasture. Progeny from both old growth and secondary forest contexts were predominantly outcrossed (tm=1.00) and experienced low levels of biparental inbreeding (tm-ts=0.00-0.04). In contrast to predictions, our results indicated that the mating patterns of V. ferruginea are relatively robust to density differences between old growth and secondary forest stands. In addition, we observed that pollen-mediated gene flow possibly maintained the genetic diversity of open-pollinated progeny arrays in stands of secondary forest adults. As part of a natural resource management strategy, we suggest that primary forest remnants should be prioritised for conservation to promote restoration of genetic diversity during forest regeneration.


Assuntos
Variação Genética , Genética Populacional , Pólen/genética , Árvores/genética , Costa Rica , DNA de Plantas/genética , Florestas , Genótipo , Magnoliopsida/genética , Repetições de Microssatélites , Modelos Genéticos , Densidade Demográfica , Reprodução/genética , Sementes/genética
10.
Appl Microbiol Biotechnol ; 99(20): 8403-17, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26115752

RESUMO

The intestinal microbiota and morphology of tilapia (Oreochromis niloticus) were investigated after the application of a multi-species probiotic containing Lactobacillus reuteri, Bacillus subtilis, Enterococcus faecium and Pediococcus acidilactici (AquaStar(®) Growout). Tilapia (55.03 ± 0.44 g) were fed either a control diet or a probiotic diet (control diet supplemented with AquaStar(®) Growout at 5 g kg(-1)). After four and eight weeks, culture-dependent analysis showed higher levels of lactic acid bacteria (LAB), enterococci and Bacillus spp. in the mucosa and digesta of fish fed AquaStar(®) Growout. At week four, polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE) revealed a higher similarity within the probiotic fed replicates than replicates of the control group; after eight weeks, the compositional dissimilarity of the microbiome profiles between the groups was greater than the dissimilarities within each group (P < 0.05). High-throughput sequencing revealed that the probiotic treatment significantly reduced the number of operational taxonomic units and species richness in the digesta. Significantly higher proportions of reads belonging to Proteobacteria and Cyanobacteria were detected in the control group whereas the probiotic-fed fish displayed a significantly higher abundance of reads assigned to the Firmicutes (which accounted for >99 % of reads). Bacillus, Cetobacterium and Mycobacterium were the dominant genera in the digesta of control fish whereas Bacillus, Enterococcus and Pediococcus were the largest constituents in probiotic-fed fish. The addition of AquaStar(®) Growout to tilapia diets led to increased populations of intraepithelial leucocytes, a higher absorptive surface area index and higher microvilli density in the intestine. These data suggest that AquaStar(®) Growout can modulate both the intestinal microbiota and morphology of tilapia.


Assuntos
Ciclídeos/anatomia & histologia , Ciclídeos/microbiologia , Microbioma Gastrointestinal , Trato Gastrointestinal/anatomia & histologia , Trato Gastrointestinal/microbiologia , Probióticos/administração & dosagem , Animais , Sequenciamento de Nucleotídeos em Larga Escala , Histocitoquímica , Microscopia Eletrônica de Transmissão
11.
Br J Anaesth ; 112(2): 281-9, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24056586

RESUMO

BACKGROUND: Goal-directed fluid therapy has been shown to improve outcomes after colorectal surgery, but the optimal type of i.v. fluid to use is yet to be established. Theoretical advantages of using hydroxyethyl starch (HES) for goal-directed therapy include a reduction in the total volume of fluid required, resulting in less tissue oedema. Recent work has demonstrated that new generations of HES have a good safety profile, but their routine use in the perioperative setting has not been demonstrated to confer outcome benefit. METHODS: We randomly assigned 202 medium to high-risk patients undergoing elective colorectal surgery to receive either balanced 6% HES (130/0.4, Volulyte) or balanced crystalloid (Hartmann's solution) as haemodynamic optimization fluid. The primary outcome measure was the incidence of gastrointestinal (GI) morbidity on postoperative day 5. Secondary outcome measures included the incidence of postoperative complications, hospital length of stay, and the effect of trial fluids on coagulation and inflammation. RESULTS: No difference was seen in the number of patients who suffered GI morbidity on postoperative day 5 [30% in the HES group vs 32% in the crystalloid group; adjusted odds ratio=0.96 (0.52-1.77)]. Subjects in the crystalloid group received more fluid [median (inter-quartile ranges) 3175 (2000-3700) vs 1875 (1500-3000) ml, P<0.001] and had a higher 24 h fluid balance [+4226 (3251-5779) vs +3610 (2443-4519) ml, P<0.001]. No difference in the incidence of postoperative complications was seen between the groups. CONCLUSIONS: Goal-directed fluid therapy is possible with either crystalloid or HES. There is no evidence of a benefit in using HES over crystalloid, despite its use resulting in a lower 24 h fluid balance.


Assuntos
Coloides/uso terapêutico , Cirurgia Colorretal , Hidratação/métodos , Derivados de Hidroxietil Amido/uso terapêutico , Soluções Isotônicas/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Soluções Cristaloides , Método Duplo-Cego , Feminino , Seguimentos , Gastroenteropatias/prevenção & controle , Humanos , Inflamação/prevenção & controle , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Substitutos do Plasma/uso terapêutico , Complicações Pós-Operatórias/prevenção & controle , Lactato de Ringer
12.
J Anim Physiol Anim Nutr (Berl) ; 98(2): 279-89, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23676107

RESUMO

In recent years, aquaculture research has focused on probiotics, prebiotics, and ß-glucans, in order to improve health status and growth performance. Information regarding the effects of ß-glucan on growth performance and intestinal immunity of mirror carp (Cyprinus carpio L.) is scarce. An experiment was therefore conducted to investigate the effects of a yeast ß-glucan preparation (MacroGard(®) ) on growth performance, intestinal morphology and haemato-immunological indices of mirror carp. Carp (initial weight 11.1 ± 0.0 g) were fed highly purified diets supplemented with 0% (control), 0.1%, 1% or 2% MacroGard(®) for 8 weeks. Fish fed diets containing 1% and 2% MacroGard(®) showed significant improvements in weight gain, specific growth rate and feed conversion ratio compared to fish fed both the control and the 0.1% MacroGard(®) containing diet. Histological appraisal of the intestine showed a significantly higher infiltration of leucocytes into the epithelial layer of fish fed diets supplemented with 1% and 2% MacroGard(®) in the anterior intestine compared to fish fed the control and 0.1% MacroGard(®) diet. This effect was not observed in the posterior intestine. There were no significant differences in the intestinal absorptive surface area and number of goblet cells in either intestinal region. At the end of the experiment, the haematological status of the fish was examined. Compared to control fed fish, the haematocrit value was significantly elevated in fish fed the 2% MacroGard(®) diet. Furthermore, the blood monocyte fraction was significantly higher in fish fed the 1% and 2% MacroGard(®) diets. No significant changes were observed in the other blood parameters assessed. The present study shows that high dietary ß-glucan inclusion increases growth performance without detrimental effects on the health indicators assessed. Increased intraepithelial leucocytes in the anterior intestine may indicate a localized immune response; no detrimental effects on intestinal morphology were observed.


Assuntos
Carpas/sangue , Carpas/crescimento & desenvolvimento , Suplementos Nutricionais , Glucanos/farmacologia , Intestinos/efeitos dos fármacos , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Carpas/imunologia , Dieta/veterinária , Glucanos/administração & dosagem
13.
Proc Biol Sci ; 280(1766): 20130548, 2013 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-23843384

RESUMO

Tropical tree communities are shaped by local-scale habitat heterogeneity in the form of topographic and edaphic variation, but the life-history stage at which habitat associations develop remains poorly understood. This is due, in part, to the fact that previous studies have not accounted for the widely disparate sample sizes (number of stems) that result when trees are divided into size classes. We demonstrate that the observed habitat structuring of a community is directly related to the number of individuals in the community. We then compare the relative importance of habitat heterogeneity to tree community structure for saplings, juveniles and adult trees within seven large (24-50 ha) tropical forest dynamics plots while controlling for sample size. Changes in habitat structuring through tree life stages were small and inconsistent among life stages and study sites. Where found, these differences were an order of magnitude smaller than the findings of previous studies that did not control for sample size. Moreover, community structure and composition were very similar among tree sub-communities of different life stages. We conclude that the structure of these tropical tree communities is established by the time trees are large enough to be included in the census (1 cm diameter at breast height), which indicates that habitat filtering occurs during earlier life stages.


Assuntos
Ecossistema , Árvores/fisiologia , Clima Tropical , Biodiversidade , Densidade Demográfica , Dinâmica Populacional , Árvores/anatomia & histologia , Árvores/crescimento & desenvolvimento
14.
Fish Shellfish Immunol ; 35(4): 1097-104, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23871840

RESUMO

The application of probiotics in aquaculture has received concerted research efforts but the localised intestinal immunological response of fish to probiotic bacteria is poorly understood. Therefore, a study was conducted to evaluate the probiotic effect of Pediococcus acidilactici on Nile tilapia (Oreochromis niloticus) with specific emphasis on intestinal health and probiotic levels as well as system level responses such as growth performance, feed utilization and haemato-immunological parameters under non-challenged conditions. Fish (9.19 ± 0.04 g) were fed either a control diet or a P. acidilactici supplemented diet (at 2.81 × 10(6) CFU g(-)(1)) for six weeks. At the end of the study the probiotic was observed to populate the intestine, accounting for ca. 3% (1.59 × 10(5) CFU g(-)(1)) of the cultivable intestinal bacterial load. Real-time PCR indicated that the probiotic treatment may potentiate the immune-responsiveness of the intestine as up-regulation of the gene expression of the pro-inflammatory cytokine TNFα was observed in the probiotic fed fish (P < 0.05). Light microscopy observations revealed elevated intraepithelial leucocyte (IEL) levels in the intestine of P. acidilactici fed tilapia after six weeks (P < 0.05) of feeding and a trend towards elevated goblet cells was also observed after six weeks feeding (P = 0.08). Concomitantly at week six, along with elevated IELs and elevated TNFα mRNA levels in the intestine, an increased abundance of circulating neutrophils and monocytes were observed in fish fed the probiotic supplemented diet (P < 0.05). This haemopoietic expansion of innate immune cells could be reflective of an elevated state of immuno-readiness. Together these results suggest that the probiotic has a protective action on the intestinal mucosal cells, stimulating the innate immune response after feeding for a period of six weeks. These immunological modulations did not impair growth performance or the remaining haematological and zootechnical parameters compared to the control group (P > 0.05).


Assuntos
Ciclídeos/imunologia , Proteínas de Peixes/genética , Imunidade Inata , Pediococcus/fisiologia , Fator de Necrose Tumoral alfa/genética , Ração Animal/análise , Animais , Ciclídeos/genética , Ciclídeos/crescimento & desenvolvimento , Ciclídeos/metabolismo , DNA Bacteriano/genética , DNA Bacteriano/metabolismo , Dieta/veterinária , Proteínas de Peixes/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/imunologia , Mucosa Intestinal/microbiologia , Masculino , Pediococcus/genética , Probióticos/administração & dosagem , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Análise de Sequência de DNA/veterinária , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima
15.
Fish Shellfish Immunol ; 35(6): 1948-56, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24161776

RESUMO

A feeding trial was conducted to determine the effect of dietary administration of Pediococcus acidilactici MA18/5M and short chain fructooligosaccharides (scFOS) on Atlantic salmon (Salmo salar L.) intestinal health. Salmon (initial average weight 250 g) were allocated into triplicate sea pens and were fed either a control diet (commercial diet: 45% protein, 20% lipid) or a synbiotic treatment diet (control diet + P. acidilactici at 3.5 g kg(-1) and 7 g kg(-1) scFOS) for 63 days. At the end of this period, fish were sampled for intestinal microbiology, intestinal histology and the expression of selected immune-related genes (IL1ß, TNFα, IL8, TLR3 and MX-1) in the intestine. Compared to the control fish, the total bacterial levels were significantly lower in the anterior mucosa, posterior mucosa and posterior digesta of the synbiotic fed fish. qPCR revealed good recovery (log 6 bacteria g(-1)) of the probiotic in the intestinal digesta of the synbiotic fed fish and PCR-DGGE revealed that the number of OTUs, as well as the microbial community diversity and richness were significantly higher in the anterior digesta of the synbiotic fed fish than the control. Compared to the control fed fish, the mucosal fold (villi) length and the infiltration of epithelial leucocytes were significantly higher in the anterior and posterior intestine, respectively, in the synbiotic group. Real-time PCR demonstrated that all of the genes investigated were significantly up-regulated in the anterior and posterior intestine of the synbiotic fed salmon, compared to the control group. At the systemic level, serum lysozyme activity was significantly higher in the synbiotic fed fish and growth performance, feed utilisation and biometric measurements (condition factor, gutted weight and gut loss) were not affected. Together these results suggest that the synbiotic modulation of the gut microbiota has a protective action on the intestinal mucosal cells, improving morphology and stimulating the innate immune response without negatively affecting growth performance or feed utilization of farmed Atlantic salmon.


Assuntos
Oligossacarídeos/farmacologia , Pediococcus/química , Probióticos/farmacologia , Salmo salar/imunologia , Salmo salar/microbiologia , Simbióticos/análise , Ração Animal/análise , Animais , Citocinas/genética , Citocinas/metabolismo , Dieta/veterinária , Carboidratos da Dieta/administração & dosagem , Carboidratos da Dieta/farmacologia , Suplementos Nutricionais/análise , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Regulação da Expressão Gênica , Mucosa Intestinal/metabolismo , Intestinos/imunologia , Intestinos/microbiologia , Microbiota , Proteínas de Resistência a Myxovirus/genética , Proteínas de Resistência a Myxovirus/metabolismo , Oligossacarídeos/administração & dosagem , Probióticos/administração & dosagem , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Salmo salar/metabolismo , Receptor 3 Toll-Like/genética , Receptor 3 Toll-Like/metabolismo
16.
J Appl Microbiol ; 115(5): 1091-106, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23889777

RESUMO

AIM: To assess the effects of dietary Saccharomyces cerevisiae ß-(1,3)(1,6)-D-glucan supplementation (MacroGard(®)) on mirror carp (Cyprinus carpio L.) intestinal microbiota and ultrastructure of the enterocyte apical brush border. METHODS AND RESULTS: Carp were fed either a control diet or diets supplemented with 0.1, 1 or 2% w/w MacroGard(®). Culture-dependent microbiology revealed that aerobic heterotrophic bacterial levels were unaffected by dietary MacroGard(®) after 2 and 4 weeks. No effects were observed on the allochthonous lactic acid bacteria (LAB) populations at either time point; however, reduced autochthonous LAB populations were observed at week 4. PCR-DGGE confirmed these findings through a reduction in the abundance of autochthonous Lactococcus sp. and Vagococcus sp. in MacroGard(®)--fed fish compared with the control-fed fish. Overall, sequence analysis detected microbiota belonging to the phyla Proteobacteria, Firmicutes, Fusobacteria and unidentified uncultured bacteria. DGGE analyses also revealed that dietary MacroGard(®) reduced the number of observed taxonomical units (OTUs) and the species richness of the allochthonous microbiota after 2 weeks, but not after 4 weeks. In contrast, dietary MacroGard(®) reduced the number of OTUs, the species richness and diversity of the autochthonous microbiota after 2 weeks, and those parameters remained reduced after 4 weeks. Transmission electron microscopy revealed that intestinal microvilli length and density were significantly increased after 4 weeks in fish fed diets supplemented with 1% MacroGard(®). CONCLUSIONS: This study indicates that dietary MacroGard(®) supplementation modulates intestinal microbial communities of mirror carp and influences the morphology of the apical brush border. SIGNIFICANCE AND IMPACT OF THE STUDY: To the authors' knowledge, this is the first study to investigate the effects of ß-(1,3)(1,6)-D-glucans on fish gut microbial communities, using culture-independent methods, and the ultrastructure of the apical brush border of the enterocytes in fish. This prebiotic-type effect may help to explain the mechanisms in which ß-glucans provide benefits when fed to fish.


Assuntos
Ração Animal , Carpas/microbiologia , Glucanos/farmacologia , Intestinos/microbiologia , Intestinos/ultraestrutura , Microbiota/efeitos dos fármacos , Animais , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Eletroforese em Gel de Gradiente Desnaturante , Suplementos Nutricionais/análise , Microscopia Eletrônica de Transmissão , Microvilosidades/ultraestrutura , Reação em Cadeia da Polimerase , Prebióticos
17.
Braz J Biol ; 83: e271983, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37283337

RESUMO

This study aimed to assess the genetic differentiation and relationship among five sea cucumber species from the Red Sea in Egypt, namely Holothuria atra, H. impatiens, H. leucospilota, Actinopyga crassa and A. mauritiana, using Inter Simple Sequence Repeated (ISSR) and Start Codon Targeted (SCoT) markers. A collection of 100 specimens, with 20 individuals per species, was gathered for the analysis. With ten ISSR primers, 135 amplified bands were detected, including 11 distinct species-specific bands, indicating high-level polymorphism among species. Using ten SCoT primers, 151 amplicons were generated, including 30 species-specific bands, with 52% polymorphic bands indicating high-level polymorphism among species. The degree of genetic similarity (GS) among the different genotypes of species was calculated based on ISSR bands analysis, which ranged from 93% between H. atra and H. impatiens to 86% between H. atra and A. crassa. The highest genetic similarity was observed between H. atra and H. impatiens (90%), while the lowest was identified between A. crassa and A. mauritiana (75%) using SCoT bands. Notably, the ISSR and SCoT-based DNA analysis revealed similar genetic relationships between H. atra and H. impatiens compared to other sea cucumber species studied. This study provides new insights into the genetic diversity and relationship among sea cucumber species in the Red Sea, which could have implications for their conservation and management.


Assuntos
Pepinos-do-Mar , Humanos , Animais , Pepinos-do-Mar/genética , Egito , Oceano Índico , Polimorfismo Genético , Genótipo , Primers do DNA , Variação Genética/genética , Filogenia
18.
Braz J Biol ; 83: e270808, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37075379

RESUMO

Catfish (Clarias gariepinus) meat isn't preferred by consumers in compared to other fish species meat, thus to enhance the use of catfish meat, ready to eat catfish fingers were prepared with some plants additives (amla and ginger powder). The mean objective of this study was to assess the impact of amla and ginger powder on catfish finger qualities in terms of physical, chemical, microbiological, and sensorial parameters under stored at a low temperature (5 ± 1 °C). The obtained results were compared with those of a control sample (basic formula) and a sample containing the synthetic antioxidant. During the storage period, the levels of pH, thiobarbituric acid, total volatile basic nitrogen, trimethylamine, total bacteria count, psychrophilic bacteria, molds and yeasts counts increased dramatically, although the values remained within acceptable ranges. The findings also revealed, that amla and ginger powder considerably (p < 0.05) reduced the changes in quality parameters, as well as there was a considerable increase in the quality parameter in all treated samples than in the control. Finally, amla and ginger powder can be a substitute for synthetic antioxidants and antimicrobials. These findings suggest that the powder of amla and ginger are suitable for use as a natural antioxidants and antimicrobials to extend the shelf-life of animal products.


Assuntos
Peixes-Gato , Phyllanthus emblica , Zingiber officinale , Animais , Pós , Antioxidantes/farmacologia
19.
Psychol Med ; 42(9): 1969-76, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22251707

RESUMO

BACKGROUND: Previous studies on the relationship between blood pressure (BP) and psychological morbidity are conflicting. To resolve this confusing picture we examined the hypothesis that there is a non-linear relationship between panic and systolic BP (SBP) and explored the association of generalized anxiety symptoms with SBP. Method We used data from the population-based Nord-Trøndelag health study (HUNT) in which all 92 936 individuals aged ≥20 years residing in one Norwegian county were invited to participate. Panic was assessed using one item from the anxiety subscale of the Hospital Anxiety and Depression Scale (HADS) and generalized anxiety with the remaining six items of this subscale. SBP was the mean of two measurements by an automatic device. RESULTS: A total of 64 871 respondents had SBP recorded (70%). Both unadjusted (n=61 408) and adjusted analyses provided evidence for a non-linear relationship between panic and SBP, represented by a U-shaped curve with a minimum prevalence of panic at around 140 mmHg. The relationship was strengthened after adjustment for confounders, with the quadratic term significantly associated with panic (p=0.03). Generalized anxiety symptoms were associated only with low SBP. CONCLUSIONS: The U-shaped relationship between SBP and panic provides a unifying explanation for the separate strands of published literature in this area. The results support the hypothesis that high BP and panic disorder could share brainstem autonomic and serotonergic abnormalities. By contrast, generalized anxiety symptoms were more common only at lower BPs, suggesting that any biological link between panic and high BP does not extend to generalized anxiety.


Assuntos
Transtornos de Ansiedade/epidemiologia , Pressão Sanguínea , Hipertensão/epidemiologia , Transtorno de Pânico/epidemiologia , Pânico , Comorbidade , Estudos Transversais , Depressão/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Noruega/epidemiologia , Razão de Chances
20.
Fish Shellfish Immunol ; 32(6): 1002-7, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22554572

RESUMO

An investigation was conducted to evaluate the effect of feeding a tropical earthworm meal (Perionyx escavatus) on the haemato-immunological response and growth performance of mirror carp (Cyprinus carpio). Fish were fed diets for a total of 88 days, fishmeal served as the main protein source in the control diet. Two remaining diets consisted of fishmeal fixed at 33.65% provision of protein and the remaining 66.35% protein was provided by soybean meal (SBM diet) or P. excavatus meal (EW diet). Compared to control and SBM fed fish (7.69 ± 0.28 and 5.92 ± 0.31 g/dl, respectively), a significant increase in haemoglobin was measured in EW fed fish (9.57 ± 0.24 g/dl). Consequently significant elevations were also observed in mean corpuscular haemoglobin (MCH; 79.13 ± 4.59 pg) and mean corpuscular haemoglobin concentration (MCHC; 22.69 ± 0.54 pg) in EW fed fish. On the contrary, compared to control and SBM fed carp total leukocyte levels (2.72 ± 0.17 and 3.10 ± 0.17 × 10(4)/mm(3), respectively) were significantly decreased in the EW group (2.15 ± 0.14 × 10(4)/mm(3)). Moreover at day 14 and 21 post immunisation with bacterin isolated from Aeromonas hydrophila fish fed the EW diet displayed a significant reduction in respiratory burst activity (RBA) compared to control and SBM fed fish. After 60 days of feeding, fish fed EW diet showed a significant elevation in final body weight compared to fish fed a fishmeal based diet (control treatment) and fish fed a soybean meal based diet. Similar improvements were observed in feed utilisation efficiency. The present study shows that feeding P. excavatus meal to mirror carp decreases some aspects of the innate immune response, but at the same time gives rise to significant enhancement of growth and feed utilisation efficiency.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal/imunologia , Carpas/crescimento & desenvolvimento , Carpas/imunologia , Dieta/veterinária , Oligoquetos , Aeromonas hydrophila , Animais , Carpas/sangue , Doenças dos Peixes/imunologia , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Imunoglobulina M/sangue , Explosão Respiratória/imunologia
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