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1.
PLoS One ; 16(9): e0250396, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34550989

RESUMO

Relative humidity (RH) was measured at hourly intervals for approximately one year in two caves at seven stations near Playa del Carmen in Quintana Roo, Mexico. Sistema Muévelo Rico is a 1.1 km long cave with 12 entrances and almost no dark zone. Río Secreto (Tuch) is a large river cave with more than 40 km of passages, and an extensive dark zone. Given the need for cave specialists to adapt to saturated humidity, presumably by cuticular thinning, the major stress of RH would be its deviation from saturation. RH in Río Secreto (Tuch) was invariant at three sites and displayed short deviations from 100% RH at the other four sites. These deviations were concentrated at the end of the nortes and beginning of the rainy season. Three of the sites in Sistema Muévelo Rico showed a similar pattern although the timing of the deviations from 100% RH was somewhat displaced. Four sites in Sistema Muévelo Rico were more variable, and were analyzed using a measure of amount of time of deviation from 100% RH for each 24 hour period. Strong seasonality was evident but, remarkably, periods of constant high humidity were not the same at all sites. In most Sistema Muévelo Rico sites, there was a detectable 24 hour cycle in RH, although it was quite weak in about half of them. For Río Secreto (Tuch) only one site showed any sign of a 24 hour cycle. The troglomorphic fauna was more or less uniformly spread throughout the caves and did not concentrate in any one area or set of RH conditions. Compared to temperature, RH is much more constant, perhaps even more constant than the amount of light. However, changes in RH as a result of global warming may have a major negative effect on the subterranean fauna.


Assuntos
Cavernas , Umidade , México , Estações do Ano , Clima Tropical
2.
J Diet Suppl ; 18(3): 227-247, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32306803

RESUMO

Few studies have focused on dose-response analyses of multi-strain probiotics in the general adult population. This study aimed at comparing how a low- and high-dose of a multi-strain probiotic supplement (containing Lactobacillus helveticus R0052, Lactobacillus rhamnosus R0011, Lactobacillus casei R0215, Pediococcus acidilactici R1001, Bifidobacterium breve R0070, Bifidobacterium longum ssp. longum BB536, Lactobacillus plantarum R1012, Lactococcus lactis ssp. lactis R1058) affected microbiota composition, transit persistence and safety in adults. After a 7-d baseline, participants were randomized to receive capsules containing 5 or 25 billion CFU, or placebo daily for 28 days, followed by a 7-d washout. Digestive health and general wellness were assessed. Fecal microbiota composition was analyzed using 16S rRNA gene amplicon sequencing and strain persistence, by qPCR. Participants' gastrointestinal and general wellbeing were unaffected. No adverse events were associated with either dose. Supplemented strains contributed to the Lactobacillus and Bifidobacterium genera detected in stool, with 0.40 ± 0.11% and 0.51 ± 0.26%, respectively, in the high-dose group. Strain-specific qPCR assays revealed variable levels of post-intervention persistence between strains. Sequencing and composition analyses using the 16S V4 region revealed a decrease in Holdemania and increase in Bacteroidales. The formulation was well tolerated in this sample of the general adult population, even at the higher dose. The strains appear to have influenced microbiota composition minimally, as expected in the absence of dysbiosis, and consistently with the dose administered. Overall, the results provide a rationale to study the effects this formulation on microbiota composition in individuals exhibiting dysbiosis associated with metabolic disorders or obesity.


Assuntos
Microbiota , Probióticos , Adulto , Bifidobacterium , Método Duplo-Cego , Fezes , Humanos , Lactobacillus , RNA Ribossômico 16S
3.
PLoS One ; 15(12): e0237051, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33382693

RESUMO

Hourly temperature was measured for approximately one year at 17 stations in three caves in Quintana Roo, Mexico. Thirteen of these stations were in the extensive twilight zones of all three caves. All seventeen stations showed seasonality in temperature with a 3°C drop during the Nortes season. Two of the caves, Muévelo Sabrosito and Muévelo Rico, showed greater variability during the winter months while in Río Secreto (Tuch) variability was greatest during the rainy season. Río Secreto is less open to the surface than the other two. All sites also showed a daily temperature cycle, although it was very faint in some Río Secreto (Tuch) sites. While temperature variability is diminished relative to surface variation, its temporal pattern is worthy of further study.


Assuntos
Cavernas/química , Temperatura , Clima Tropical , Ecossistema , México , Chuva , Estações do Ano
4.
Sci Rep ; 10(1): 1389, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31996756

RESUMO

Citrus black spot (CBS) caused by the fungus Phyllosticta citricarpa occurs in tropical and sub-tropical citrus production regions and affects all varieties of citrus. In Florida, the disease cycle is unique, having only the asexual spore. This work examines incidence and severity of CBS (hard spot symptoms) on fruit in two citrus groves during 2013-2014, 2014-2015 (Grove III) and 2015-2016 (Grove II) citrus seasons. Disease incidence and severity on fruit were analyzed based on citrus season, side of tree evaluated, height within the canopy, tree health, and tree age. Results indicate an increase in CBS incidence in Grove III between 2013-2014 and 2014-2015 seasons, with more infected or symptomatic fruit on the road side of the canopy and a higher incidence above 2 meters. Tree health status affected incidence but not severity and tree age had a significant effect on severity of CBS in Grove II. Analysis of weather data conducive for infection, between 2010 and 2017, indicated an average of 172 days per year (range: 104-261 days) when the temperature (15-35 °C) and relative humidity (RH ≥ 90% for 8 consecutive hours) were conducive for infection of fruit and an average of 98 days per year (range: 72-123 days) when the fruit were susceptible to infection.


Assuntos
Ascomicetos/isolamento & purificação , Citrus/microbiologia , Doenças das Plantas/microbiologia , Tempo (Meteorologia)
5.
World J Clin Cases ; 6(15): 961-984, 2018 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-30568952

RESUMO

AIM: To assess the effects of probiotic Medilac-S® as adjunctive therapy for the induction of remission of ulcerative colitis (UC) in a Chinese population through a systematic review and meta-analysis. METHODS: A systematic literature search was conducted to find randomized, controlled trials in a Chinese population with at least two study arms - a control arm which receives a conventional, oral aminosalicylate drug, and a treatment arm, which administers the same conventional drug in conjunction with the probiotic Medilac-S® per os. Both English and Chinese databases were searched, including PubMed, EMBASE, Google Scholar, Chinese National Knowledge Infrastructure, Wanfang Data, and VIP Search, and study data was extracted onto standardized abstraction sheets. Meta-analyses were conducted for primary and secondary outcomes of interest using a fixed or random effects model. The primary outcome was the induction of clinical remission and the secondary outcomes included changes in Sutherland index, endoscopic and histological scores, proportion of reported clinical symptoms and adverse events (AEs). For outcomes with sufficient data, the type of conventional drug therapy was also assessed to determine if the effects of combination therapy with Medilac-S® was influenced by drug type. All tests were conducted using a type I error rate of 0.05 and all confidence intervals (CI) were based on a 95% confidence level. Review protocol was uploaded to PROSPERO (CRD42018085658 upon completion). RESULTS: Fifty-three clinical trials with a total of 3984 participants were identified and included in the review. Medilac-S® adjunctive therapy significantly improved induction of clinical remission (RR = 1.21; 95%CI: 1.18-1.24; P < 0.0001) with the estimated likelihood of effective treatment, on average, 21% higher for those consuming the probiotic. Sutherland index scores showed the control mean was on average 3.10 (CI: 2.41-3.78; P = 0.0428) units greater than the treatment mean, thereby demonstrating significant improvement in participants taking the probiotic. Similarly, a significant difference was seen between the overall reduction of endoscopic and histological scores of control and treatment arm participants, with score decreases in the control groups 0.71 (CI: 0.3537-1.0742) and 1.1 (CI: 0.9189-1.2300) units smaller than treatment group score decreases. The proportion of participants reporting clinical symptoms, (abdominal pain, tenesmus, blood and mucous in stool, and diarrhea) was significantly reduced after combination therapy with Medilac-S® (P < 0.0001) and estimated to be on average 44% (RR = 0.44, CI: 0.32-0.59), 53% (RR = 0.53, CI: 0.38-74), 40% (RR = 0.40, CI: 0.28-0.58) and 47% (RR = 0.47 CI: 0.36-0.42) respectively, of the proportion of individuals reporting the aforementioned symptoms after conventional therapy alone. The risk of AEs was also significantly reduced with adjunctive Medilac-S® therapy. The proportion of individuals in the treatment groups reporting AEs was an estimated 72% of the proportion of individuals in the control groups reporting AEs (RR = 0.72, CI: 0.55-0.94, P = 0.0175). Upon comparing effect means for different drug types in conjunction with Medilac-S®, evidence of significant variability (P < 0.0001) was observed, and sulfasalazine was found to be the most effective drug in both primary and secondary outcomes. CONCLUSION: Evidence suggests Medilac-S® adjunctive therapy should be considered standard care for UC in a Chinese population because it aids in the induction of clinical remission, improves symptoms of the gastrointestinal tract and reduces risk of AEs.

6.
Nutr Res ; 60: 33-42, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30527258

RESUMO

Dietary fiber stimulates the growth of potentially beneficial bacteria (eg, bifidobacteria), yet most Americans do not meet daily fiber recommendations. Resistant maltodextrin (RMD), a fermentable functional fiber, may help individuals meet total fiber recommendations and potentially increase bifidobacteria. It was hypothesized that fecal bifidobacteria counts/ng fecal DNA would increase after adding 25 g RMD to inadequate fiber diets of healthy adults. In this double-blind, controlled crossover study, 51 participants (26.3 ± 6.8 years, mean ± SD) were randomized to consume 0, 15, and 25 g RMD daily for 3 weeks followed by a 2-week washout. Participants collected all stools for 2 days at weeks 0 and 3 of each intervention for stool wet weight (WW) measurements and fecal bifidobacteria counts. Weekly 24-hour dietary recalls assessed total fiber intake. Only 25 g RMD resulted in a change (final minus baseline) in bifidobacteria that was significant compared with 0 g (0.17 ± 0.09 vs -0.17 ± 0.09 log10[counts], respectively, mean ± SEM, P = .008). Stool WW increased only with 25 g (150 ± 11 vs baseline 121±11 g/d; P = .011). Mean daily total fiber intake (including RMD) was significantly higher (both P< .001) with 15 g (17.8 ± 0.6 g/1000 kcal or 4184 kJ) and 25 g (25.3 ± 1.1 g/1000 kcal) compared with 0 g RMD (8.4±0.4 g/1000 kcal). Mean daily total fiber intakes exceeded recommendations (14 g/1000 kcal) with 15 and 25 g of RMD, and 25 g RMD increased fecal bifidobacteria counts and stool WW, suggesting health benefits from increasing total fiber intake.


Assuntos
Bifidobacterium/efeitos dos fármacos , Defecação/efeitos dos fármacos , Fibras na Dieta/farmacologia , Fezes , Microbioma Gastrointestinal/efeitos dos fármacos , Intestinos/efeitos dos fármacos , Polissacarídeos/farmacologia , Adulto , Bifidobacterium/crescimento & desenvolvimento , Estudos Cross-Over , Dieta , Fibras na Dieta/administração & dosagem , Método Duplo-Cego , Fezes/microbiologia , Feminino , Fermentação , Humanos , Intestinos/microbiologia , Masculino , Polissacarídeos/administração & dosagem , Valores de Referência , Amido , Adulto Jovem
7.
Ecol Evol ; 7(17): 6996-7009, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28904778

RESUMO

Herbivory has long been recognized as a significant driver of plant population dynamics, yet its effects along environmental gradients are unclear. Understanding how weather modulates plant-insect interactions can be particularly important for predicting the consequences of exotic insect invasions, and an explicit consideration of weather may help explain why the impact can vary greatly across space and time. We surveyed two native prickly pear cactus species (genus Opuntia) in the Florida panhandle, USA, and their specialist insect herbivores (the invasive South American cactus moth, Cactoblastis cactorum, and three native insect species) for five years across six sites. We used generalized linear mixed models to assess the impact of herbivory and weather on plant relative growth rate (RGR) and sexual reproduction, and we used Fisher's exact test to estimate the impact of herbivory on survival. Weather variables (precipitation and temperature) were consistently significant predictors of vital rate variation for both cactus species, in contrast to the limited and varied impacts of insect herbivory. Weather only significantly influenced the impact of herbivory on Opuntia humifusa fruit production. The relationships of RGR and fruit production with precipitation suggest that precipitation serves as a cue in determining the trade-off in the allocation of resources to growth or fruit production. The presence of the native bug explained vital rate variation for both cactus species, whereas the invasive moth explained variation only for O. stricta. Despite the inconsistent effect of herbivory across vital rates and cactus species, almost half of O. stricta plants declined in size, and the invasive insect negatively affected RGR and fruit production. Given that fruit production was strongly size-dependent, this suggests that O. stricta populations at the locations surveyed are transitioning to a size distribution of predominantly smaller sizes and with reduced sexual reproduction potential.

8.
Am J Clin Nutr ; 105(3): 758-767, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28228426

RESUMO

Background: Rhinoconjunctivitis-specific quality of life is often reduced during seasonal allergies. The Mini Rhinoconjunctivitis Quality of Life Questionnaire (MRQLQ) is a validated tool used to measure quality of life in people experiencing allergies (0 = not troubled to 6 = extremely troubled). Probiotics may improve quality of life during allergy season by increasing the percentage of regulatory T cells (Tregs) and inducing tolerance.Objective: The objective of this study was to determine whether consuming Lactobacillus gasseri KS-13, Bifidobacterium bifidum G9-1, and B. longum MM-2 compared with placebo would result in beneficial effects on MRQLQ scores throughout allergy season in individuals who typically experience seasonal allergies. Secondary outcomes included changes in immune markers as part of a potential mechanism for changes in MRQLQ scores.Design: In this double-blind, placebo-controlled, parallel, randomized clinical trial, 173 participants (mean ± SEM: age 27 ± 1 y) who self-identified as having seasonal allergies received either a probiotic (2 capsules/d, 1.5 billion colony-forming units/capsule) or placebo during spring allergy season for 8 wk. MRQLQ scores were collected weekly throughout the study. Fasting blood samples were taken from a subgroup (placebo, n = 37; probiotic, n = 35) at baseline and week 6 (predicted peak of pollen) to determine serum immunoglobulin (Ig) E concentrations and Treg percentages.Results: The probiotic group reported an improvement in the MRQLQ global score from baseline to pollen peak (-0.68 ± 0.13) when compared with the placebo group (-0.19 ± 0.14; P = 0.0092). Both serum total IgE and the percentage of Tregs increased from baseline to week 6, but changes were not different between groups.Conclusions: This combination probiotic improved rhinoconjunctivitis-specific quality of life during allergy season for healthy individuals with self-reported seasonal allergies; however, the associated mechanism is still unclear. This trial was registered at clinicaltrials.gov as NCT02349711.


Assuntos
Bifidobacterium bifidum , Bifidobacterium longum , Conjuntivite Alérgica , Lactobacillus gasseri , Probióticos/uso terapêutico , Qualidade de Vida , Rinite Alérgica Sazonal , Atividades Cotidianas , Adulto , Conjuntivite Alérgica/complicações , Conjuntivite Alérgica/tratamento farmacológico , Método Duplo-Cego , Olho/patologia , Feminino , Humanos , Imunoglobulina E/sangue , Masculino , Nariz/patologia , Rinite Alérgica Sazonal/complicações , Rinite Alérgica Sazonal/tratamento farmacológico , Linfócitos T Reguladores/metabolismo
9.
PLoS One ; 12(1): e0170755, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28125679

RESUMO

Fungal growth inhibition on solid media has been historically measured and calculated based on the average of perpendicular diameter measurements of growth on fungicide amended media. We investigated the sensitivity of the calculated area (DA) and the measured area (MA) for assessing fungicide growth inhibition of the ascomycete, Phyllosticta citricarpa on solid media. Both the calculated, DA and the actual measured area, MA were adequate for distinguishing significant treatment effects of fungicide on fungal growth, however MA was more sensitive at identifying significant differences between the controls and fungicide concentrations below 5 ppm.


Assuntos
Ascomicetos/efeitos dos fármacos , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão/estatística & dados numéricos , Fungicidas Industriais/farmacologia , Ascomicetos/crescimento & desenvolvimento , Meios de Cultura/farmacologia
10.
PLoS One ; 11(8): e0160408, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27532611

RESUMO

One of the most challenging fauna to study in situ is the obligate cave fauna because of the difficulty of sampling. Cave-limited species display patchy and restricted distributions, but it is often unclear whether the observed distribution is a sampling artifact or a true restriction in range. Further, the drivers of the distribution could be local environmental conditions, such as cave humidity, or they could be associated with surface features that are surrogates for cave conditions. If surface features can be used to predict the distribution of important cave taxa, then conservation management is more easily obtained. We examined the hypothesis that the presence of major faunal groups of cave obligate species could be predicted based on features of the earth surface. Georeferenced records of cave obligate amphipods, crayfish, fish, isopods, beetles, millipedes, pseudoscorpions, spiders, and springtails within the area of Appalachian Landscape Conservation Cooperative in the eastern United States (Illinois to Virginia and New York to Alabama) were assigned to 20 x 20 km grid cells. Habitat suitability for these faunal groups was modeled using logistic regression with twenty predictor variables within each grid cell, such as percent karst, soil features, temperature, precipitation, and elevation. Models successfully predicted the presence of a group greater than 65% of the time (mean = 88%) for the presence of single grid cell endemics, and for all faunal groups except pseudoscorpions. The most common predictor variables were latitude, percent karst, and the standard deviation of the Topographic Position Index (TPI), a measure of landscape rugosity within each grid cell. The overall success of these models points to a number of important connections between the surface and cave environments, and some of these, especially soil features and topographic variability, suggest new research directions. These models should prove to be useful tools in predicting the presence of species in understudied areas.


Assuntos
Cavernas , Ecossistema , Anfípodes , Animais , Região dos Apalaches , Artrópodes , Besouros , Conservação dos Recursos Naturais , Meio Ambiente , Peixes , Modelos Biológicos , Dinâmica Populacional , Especificidade da Espécie , Aranhas
11.
Br J Nutr ; 116(1): 94-103, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27169634

RESUMO

Broad-spectrum antibiotic use can disrupt the gastrointestinal microbiota resulting in diarrhoea. Probiotics may be beneficial in managing this type of diarrhoea. The aim of this 10-week randomised, double-blind, placebo-controlled, parallel study was to investigate the effect of Lactobacillus helveticus R0052 and Lactobacillus rhamnosus R0011 supplementation on antibiotic-associated diarrhoea in healthy adults. Subjects were randomised to receive 1 week of amoxicillin-clavulanic acid (875 mg/125 mg) once per day, plus a daily dose of 8×109 colony-forming units of a multi-strain probiotic (n 80) or placebo (n 80). The probiotic or placebo intervention was maintained for 1 week after completion of the antibiotic. Primary study outcomes of consistency and frequency of bowel movements were not significantly different between the probiotic and placebo groups. The secondary outcomes of diarrhoea-like defecations, Gastrointestinal Symptoms Rating Scale scores, safety parameters and adverse events were not significantly different between the probiotic intervention and the placebo. A post hoc analysis on the duration of diarrhoea-like defecations showed that probiotic intervention reduced the length of these events by 1 full day (probiotic, 2·70 (sem 0·36) d; placebo, 3·71 (sem 0·36) d; P=0·037; effect size=0·52). In conclusion, this study provides novel evidence that L. helveticus R0052 and L. rhamnosus R0011 supplementation significantly reduced the duration of diarrhoea-like defecations in healthy adults receiving antibiotics.


Assuntos
Combinação Amoxicilina e Clavulanato de Potássio/efeitos adversos , Antibacterianos/efeitos adversos , Diarreia/induzido quimicamente , Lacticaseibacillus rhamnosus , Lactobacillus helveticus , Probióticos/farmacologia , Adulto , Diarreia/microbiologia , Método Duplo-Cego , Humanos
12.
Nutr Res ; 36(1): 80-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26773784

RESUMO

The health benefits of nuts may, in part, be due to the fiber that provides substrate for the maintenance of a healthy and diverse microbiota. We hypothesized that consuming almonds would benefit immune status through improving diet quality and modulation of microbiota composition in parents and their children, while improving gastrointestinal function. In a crossover trial, 29 parents (35 ± 0.6 years) and their children (n = 29; 4 ± 0.2 years; pairs) consumed 1.5 and 0.5 oz, respectively, of almonds and/or almond butter or control (no almonds) for 3 weeks followed by 4-week washouts. Parents completed daily questionnaires of stool frequency and compliance with nut intake. The Gastrointestinal Symptom Response Scale was administered weekly. Participants provided stools for microbiota analysis and saliva for secretory immunoglobulin A. Serum antioxidant/proinflammatory balance was determined in parents. From weekly dietary recalls (Automated Self-Administered 24-Hour Dietary Recall), nutrient and energy intake were assessed and Healthy Eating Index-2010 scores were calculated. Consuming almonds increased total Healthy Eating Index score from 53.7 ± 1.8 to 61.4 ± 1.4 (parents) and 53.7 ± 2.6 to 61.4 ± 2.2 (children; P < .001). Minimal changes in gastrointestinal symptoms and no change in stool frequency were noted with the almond intervention. Microbiota was stable at the phylum and family level, but genus-level changes occurred with nut intake, especially in children. No differences were observed for immune markers. Although higher intakes of almonds or longer interventions may be needed to demonstrate effects on immune status, a moderate intake of almonds improves diet quality in adults and their young children and modulates microbiota composition.


Assuntos
Fenômenos Fisiológicos da Nutrição Infantil , Dieta/efeitos adversos , Política Nutricional , Nozes , Pais , Cooperação do Paciente , Prunus dulcis , Adulto , Criança , Pré-Escolar , Condimentos , Estudos Cross-Over , Disbiose/epidemiologia , Disbiose/prevenção & controle , Estudos de Viabilidade , Feminino , Florida/epidemiologia , Preferências Alimentares , Microbioma Gastrointestinal , Humanos , Doenças do Sistema Imunitário/epidemiologia , Doenças do Sistema Imunitário/prevenção & controle , Masculino , Nozes/química , Prunus dulcis/química , Risco
13.
J Am Coll Nutr ; 34(6): 459-69, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25909149

RESUMO

OBJECTIVE: This study determined whether older adults who consumed a probiotic mixture would have a greater proportion of circulating CD4+ lymphocytes, altered cytokine production, and a shift in intestinal microbiota toward a healthier microbial community. METHODS: Participants (70 ± 1 years [mean ± SEM]; n = 32) consumed a probiotic (Lactobacillus gasseri KS-13, Bifidobacterium bifidum G9-1, and Bifidobacterium longum MM2) or a placebo twice daily for 3 weeks with a 5-week washout period between intervention periods. Blood and stools were collected before and after each intervention. The percentage of circulating CD4+ lymphocytes and ex vivo mitogen-stimulated cell cytokine production were measured. In stools, specific bacterial targets were quantified via quantitative polymerase chain reaction (qPCR) and community composition was determined via pyrosequencing. RESULTS: During the first period of the crossover the percentage of CD4+ cells decreased with the placebo (48% ± 3% to 31% ± 3%, p < 0.01) but did not change with the probiotic (44% ± 3% to 42% ± 3%) and log-transformed concentrations of interleukin-10 increased with the probiotic (1.7 ± 0.2 to 3.4 ± 0.2, p < 0.0001) but not the placebo (1.7 ± 0.2 to 2.1 ± 0.2). With the probiotic versus the placebo a higher percentage of participants had an increase in fecal bifidobacteria (48% versus 30%, p < 0.05) and lactic acid bacteria (55% versus 43%, p < 0.05) and a decrease in Escherichia coli (52% versus 27%, p < 0.05). Several bacterial groups matching Faeacalibactierium prausnitzii were more prevalent in stool samples with the probiotic versus placebo. CONCLUSIONS: The probiotic maintained CD4+ lymphocytes and produced a less inflammatory cytokine profile possibly due to the changes in the microbial communities, which more closely resembled those reported in healthy younger populations.


Assuntos
Envelhecimento/fisiologia , Bifidobacterium/fisiologia , Citocinas/sangue , Microbioma Gastrointestinal/fisiologia , Lactobacillus/fisiologia , Probióticos/administração & dosagem , Idoso , Envelhecimento/imunologia , Carga Bacteriana/classificação , Contagem de Linfócito CD4 , Estudos Cross-Over , Método Duplo-Cego , Fezes/microbiologia , Gastroenteropatias/epidemiologia , Microbioma Gastrointestinal/imunologia , Trato Gastrointestinal/microbiologia , Trato Gastrointestinal/fisiologia , Humanos , Inflamação , Placebos , Probióticos/efeitos adversos , Inquéritos e Questionários
14.
J Am Coll Nutr ; 34(6): 478-87, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25866155

RESUMO

BACKGROUND: Mushrooms are widely cited for their medicinal qualities, yet very few human intervention studies have been done using contemporary guidelines. OBJECTIVE: The aim of this study was to determine whether consumption of whole, dried Lentinula edodes (shiitake) mushrooms could improve human immune function. Primary objectives were to ascertain whether L. edodes consumption would improve γδ-T cell proliferation and activation responses, quantify a dose response, and elicit cytokine secretion patterns. Secondary objectives included determining changes in natural killer T (NK-T) cell proliferation and activation, secretory immunoglobulin A (sIgA) in saliva, and C-reactive protein (CRP) in serum. DESIGN: Fifty-two healthy males and females, aged 21-41 years, participated in a 4-week parallel group study, consuming either 5 or 10 g of mushrooms daily. Each subject had blood drawn before and after 4 weeks of daily L. edodes consumption. Saliva and serum were also collected. Peripheral blood mononuclear cells were cultured in autologous serum for 24 hours or 6 days, stained, and examined by flow cytometry. RESULTS: Eating L. edodes for 4 weeks resulted in increased ex vivo proliferation of γδ-T (60% more, p < 0.0001) and NK-T (2-fold more, p < 0.0001) cells. Both cell types also demonstrated a greater ability to express activation receptors, suggesting that consuming mushrooms improved cell effector function. The increase in sIgA implied improved gut immunity. The reduction in CRP suggested lower inflammation. The pattern of cytokines secreted before and after mushroom consumption was significantly different; consumption resulted in increased interleukin (IL)-4, IL-10, tumor necrosis factor (TNF)-α, and IL-1α levels, a decreased macrophage inflammatory protein-1α/chemokine C-C ligand 3 (MIP-1α/CCL3) level, and no change to IL-6, IL-1ß, MIP-1ß, IL-17 and interferon (IFN)-γ levels. CONCLUSIONS: Regular L. edodes consumption resulted in improved immunity, as seen by improved cell proliferation and activation and increased sIgA production. The changes observed in cytokine and serum CRP levels suggest that these improvements occurred under conditions that were less inflammatory than those that existed before consumption.


Assuntos
Dieta , Imunidade/fisiologia , Cogumelos Shiitake , Adulto , Biomarcadores/análise , Biomarcadores/sangue , Proteína C-Reativa/análise , Células Cultivadas , Citocinas/sangue , Citocinas/metabolismo , Feminino , Humanos , Imunoglobulina A Secretora/análise , Imunoglobulina A Secretora/sangue , Inflamação/prevenção & controle , Intestinos/imunologia , Células Matadoras Naturais/imunologia , Leucócitos Mononucleares/metabolismo , Ativação Linfocitária/fisiologia , Masculino , Saliva/imunologia , Linfócitos T/imunologia , Adulto Jovem
15.
Br J Nutr ; 113(3): 426-34, 2015 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-25604727

RESUMO

Acute psychological stress is positively associated with a cold/flu. The present randomised, double-blind, placebo-controlled study examined the effect of three potentially probiotic bacteria on the proportion of healthy days over a 6-week period in academically stressed undergraduate students (n 581) who received Lactobacillus helveticus R0052, Bifidobacterium longum ssp. infantis R0033, Bifidobacterium bifidum R0071 or placebo. On each day, participants recorded the intensity (scale: 0 = not experiencing to 3 = very intense) for nine cold/flu symptoms, and a sum of symptom intensity >6 was designated as a day of cold/flu. B. bifidum resulted in a greater proportion of healthy days than placebo (P≤ 0·05). The percentage of participants reporting ≥ 1 d of cold/flu during the 6-week intervention period was significantly lower with B. bifidum than with placebo (P< 0·05). There were no effects of B. infantis or L. helveticus compared with placebo on either outcome. A predictive model accounted for influential characteristics and their interactions on daily reporting of cold/flu episodes. The proportion of participants reporting a cold on any given day was lower at weeks 2 and 3 with B. bifidum and B. infantis than with placebo for the average level of stress and the most commonly reported number of hours of sleep. Daily intake of bifidobacteria provides benefit related to cold/flu outcomes during acute stress.


Assuntos
Bifidobacterium , Nível de Saúde , Influenza Humana/prevenção & controle , Probióticos/administração & dosagem , Estresse Psicológico/imunologia , Estudantes/psicologia , Índice de Massa Corporal , Método Duplo-Cego , Feminino , Humanos , Influenza Humana/epidemiologia , Influenza Humana/imunologia , Lactobacillus helveticus , Masculino , Placebos , Adulto Jovem
16.
J Acad Nutr Diet ; 114(9): 1417-23, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24948336

RESUMO

In accordance with the 2010 Dietary Guidelines for Americans, at least half of total grain intake should be whole grains. Adolescents are currently not consuming the recommended daily intake of whole grains. Research is needed to determine whether whole grains are acceptable to adolescents and whether changing their food environment to include whole-grain foods will improve intake. The aim of this study was to determine the effect of providing refined-grain or whole-grain foods to adolescents, with encouragement to eat three different grain-based foods per day, on total grain and whole-grain intakes. Middle school students (n=83; aged 11 to 15 years) were randomly assigned to either refined-grain or whole-grain foods for 6 weeks. Participants and their families were provided with weekly grains (eg, bread, pasta, and cereals), and participants were provided grain snacks at school. Intake of grains in ounce equivalents (oz eq) was determined through eight baseline and intervention targeted 24-hour diet recalls. Participants consumed 1.1±1.3 oz eq (mean±standard deviation) of whole grains at baseline, out of 5.3±2.4 oz eq of total grains. During intervention, whole-grain intake increased in the whole-grain group (0.9±1.0 to 3.9±1.8 oz eq/day), whereas those in the refined-grain group reduced whole-grain intake (1.3±1.6 to 0.3±0.3 oz eq/day; P<0.002, group by time period interaction). Total grain intake achieved was 6.4±2.1 oz eq/day and did not differ across intervention groups. Providing adolescents with whole-grain foods in their school and home environments was an effective means of achieving recommendations.


Assuntos
Grão Comestível , Comportamento Alimentar , Política Nutricional , Recomendações Nutricionais/legislação & jurisprudência , Adolescente , Índice de Massa Corporal , Criança , Registros de Dieta , Fibras na Dieta/administração & dosagem , Ingestão de Energia , Etnicidade , Feminino , Florida , Humanos , Masculino , Rememoração Mental , Estudantes
17.
Environ Manage ; 53(2): 416-28, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24174132

RESUMO

Field studies of pesticide effects on birds often utilize indicator species with the purpose of extrapolating to other avian taxa. Little guidance exists for choosing indicator species to monitor the presence and/or effects of contaminants that are labile in the environment or body, but are acutely toxic, such as anticholinesterase (anti-ChE) insecticides. Use of an indicator species that does not represent maximum exposure and/or effects could lead to inaccurate risk estimates. Our objective was to test the relevance of a priori selection of indicator species for a study on pesticide exposure to birds inhabiting fruit orchards. We used total plasma ChE activity and ChE reactivation to describe the variability in anti-ChE pesticide exposure among avian species in two conventionally managed fruit orchards. Of seven species included in statistical analyses, the less common species, chipping sparrow (Spizella passerina), showed the greatest percentage of exposed individuals and the greatest ChE depression, whereas the two most common species, American robins (Turdus migratorius) and gray catbirds (Dumatella carolinensis), did not show significant exposure. Due to their lower abundance, chipping sparrows would have been an unlikely choice for study. Our results show that selection of indicator species using traditionally accepted criteria such as abundance and ease of collection may not identify species that are at greatest risk. Our efforts also demonstrate the usefulness of conducting multiple-species pilot studies prior to initiating detailed studies on pesticide effects. A study such as ours can help focus research and resources on study species that are most appropriate.


Assuntos
Aves , Inibidores da Colinesterase/toxicidade , Exposição Ambiental/análise , Praguicidas/toxicidade , Animais , Projetos de Pesquisa , Especificidade da Espécie
18.
J Nutr ; 142(11): 2025-32, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23014489

RESUMO

The intake of whole-grain (WG) foods by adolescents is reported to be approximately one-third the recommended intake of 48 g/d. This 6-wk randomized interventional study determined the effect of replacing grains within the diet with refined-grain (RG; n = 42) or WG (n = 41) foods/d on gastrointestinal and immune health in adolescents (aged 12.7 ± 0.1 y). A variety of grain-based foods were delivered weekly to participants and their families. Participants were encouraged to eat 3 different kinds of study foods (e.g., bread, cereals, snacks)/d with goals of 0 g/d (RG) and 80 g/d (WG). Stool samples were obtained during the prebaseline and final weeks to measure bifidobacteria and lactic acid bacteria (LAB) using qPCR. Stool frequency was recorded daily. Blood was drawn at baseline and at final visits for immune markers. Across groups, total-grain intake increased by one serving. The intake of WG was similar at baseline (18 ± 3 g) between groups but increased to 60 ± 5 g in the WG group and decreased to 4 ± 1 g in the RG group. Fecal bifidobacteria increased from baseline with both interventions, but LAB increased (P < 0.05) from baseline [2.4 ± 0.2 log(10) genome equivalents (eq)] to wk 6 (3.0 ± 0.2 log(10) genome eq) in the WG group but not in the RG group (baseline: 2.9 ± 0.2 log(10) genome eq; wk 6: 3.0 ± 0.1 log(10) genome eq). There was no difference in stool frequency, serum antioxidant potential, or in vitro LPS-stimulated mononuclear cell production of inflammatory cytokines between groups. However, across both groups the number of daily stools tended to increase (P = 0.08) by 0.0034 stools/g WG or by 0.2 stools with 60 g WG, mean antioxidant potential increased by 58%, and mean production of TNF-α, IL-1ß, and IL-6 decreased by 24, 22, and 42%, respectively, between baseline and wk 6. Overall, incorporating either WG or RG foods increased serum antioxidant concentrations and decreased inflammatory cytokine production; however, WG study foods had more of an effect on aspects of gastrointestinal health.


Assuntos
Citocinas/metabolismo , Fezes/microbiologia , Análise de Alimentos , Manipulação de Alimentos , Lactobacillus/isolamento & purificação , Adolescente , Fenômenos Fisiológicos da Nutrição do Adolescente , Citocinas/genética , Dieta , Grão Comestível , Fabaceae , Feminino , Frutas , Humanos , Masculino , Verduras
19.
PLoS One ; 7(7): e38665, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22808012

RESUMO

BACKGROUND: Influenza neuraminidase (NA) is an important surface glycoprotein and plays a vital role in viral replication and drug development. The NA is found in influenza A and B viruses, with nine subtypes classified in influenza A. The complete knowledge of influenza NA evolutionary history and phylodynamics, although critical for the prevention and control of influenza epidemics and pandemics, remains lacking. METHODOLOGY/PRINCIPAL FINDINGS: Evolutionary and phylogenetic analyses of influenza NA sequences using Maximum Likelihood and Bayesian MCMC methods demonstrated that the divergence of influenza viruses into types A and B occurred earlier than the divergence of influenza A NA subtypes. Twenty-three lineages were identified within influenza A, two lineages were classified within influenza B, and most lineages were specific to host, subtype or geographical location. Interestingly, evolutionary rates vary not only among lineages but also among branches within lineages. The estimated tMRCAs of influenza lineages suggest that the viruses of different lineages emerge several months or even years before their initial detection. The d(N)/d(S) ratios ranged from 0.062 to 0.313 for influenza A lineages, and 0.257 to 0.259 for influenza B lineages. Structural analyses revealed that all positively selected sites are at the surface of the NA protein, with a number of sites found to be important for host antibody and drug binding. CONCLUSIONS/SIGNIFICANCE: The divergence into influenza type A and B from a putative ancestral NA was followed by the divergence of type A into nine NA subtypes, of which 23 lineages subsequently diverged. This study provides a better understanding of influenza NA lineages and their evolutionary dynamics, which may facilitate early detection of newly emerging influenza viruses and thus improve influenza surveillance.


Assuntos
Vírus da Influenza A/genética , Vírus da Influenza B/genética , Neuraminidase/genética , Filogenia , Proteínas Virais/genética , Animais , Teorema de Bayes , Evolução Biológica , Aves/virologia , Humanos , Vírus da Influenza A/classificação , Vírus da Influenza A/enzimologia , Vírus da Influenza B/classificação , Vírus da Influenza B/enzimologia , Influenza Aviária/virologia , Influenza Humana/virologia , Modelos Moleculares , Neuraminidase/classificação , Infecções por Orthomyxoviridae/virologia , Análise de Sequência de DNA , Proteínas Virais/classificação
20.
Infect Genet Evol ; 11(8): 2125-32, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21763464

RESUMO

Influenza A viral nucleoprotein (NP) plays a critical role in virus replication and host adaptation, however, the underlying molecular evolutionary dynamics of NP lineages are less well-understood. In this study, large-scale analyses of 5094 NP nucleotide sequences revealed eight distinct evolutionary lineages, including three host-specific lineages (human, classical swine and equine), two cross-host lineages (Eurasian avian-like swine and swine-origin human pandemic H1N1 2009) and three geographically isolated avian lineages (Eurasian, North American and Oceanian). The average nucleotide substitution rate of the NP lineages was estimated to be 2.4 × 10(-3) substitutions per site per year, with the highest value observed in pandemic H1N1 2009 (3.4 × 10(-3)) and the lowest in equine (0.9 × 10(-3)). The estimated time of most recent common ancestor (TMRCA) for each lineage demonstrated that the earliest human lineage was derived around 1906, and the latest pandemic H1N1 2009 lineage dated back to December 17, 2008. A marked time gap was found between the times when the viruses emerged and were first sampled, suggesting the crucial role for long-term surveillance of newly emerging viruses. The selection analyses showed that human lineage had six positive selection sites, whereas pandemic H1N1 2009, classical swine, Eurasian avian and Eurasian swine had only one or two sites. Protein structure analyses revealed several positive selection sites located in epitope regions or host adaptation regions, indicating strong adaptation to host immune system pressures in influenza viruses. Along with previous studies, this study provides new insights into the evolutionary dynamics of influenza A NP lineages. Further lineage analyses of other gene segments will allow better understanding of influenza A virus evolution and assist in the improvement of global influenza surveillance.


Assuntos
Evolução Molecular , Vírus da Influenza A Subtipo H1N1/genética , Nucleoproteínas/classificação , Nucleoproteínas/genética , Proteínas Virais/classificação , Proteínas Virais/genética , Animais , Sequência de Bases , Humanos , Vírus da Influenza A Subtipo H1N1/classificação , Influenza Humana/genética , Influenza Humana/virologia , Dados de Sequência Molecular , Nucleoproteínas/química , Infecções por Orthomyxoviridae/genética , Infecções por Orthomyxoviridae/virologia , Pandemias , Filogenia , Conformação Proteica , Alinhamento de Sequência , Análise de Sequência de RNA , Suínos , Proteínas Virais/química
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