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1.
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
2.
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
3.
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
4.
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
5.
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
6.
Microb Ecol ; 65(3): 652-60, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23463183

RESUMO

The predatory Bacteriovorax are Gram-negative bacteria ubiquitous in saltwater systems that prey upon other Gram-negative bacteria in a similar manner to the related genus Bdellovibrio. Among the phylogenetically defined clusters of Bacteriovorax, cluster V has only been isolated from estuaries suggesting that it may be a distinct estuarine phylotype. To assess this hypothesis, the spatial and temporal distribution of cluster V and other Bacteriovorax phylogenetic assemblages along the salinity gradient of Chesapeake Bay were determined. Cluster V was expected to be found in significantly greater numbers in low to moderate salinity waters compared to high salinity areas. The analyses of water and sediment samples from sites in the bay revealed cluster V to be present at the lower salinity and not high salinity sites, consistent with it being an estuarine phylotype. Cluster IV had a similar distribution pattern and may also be specifically adapted to estuaries. While the distribution of clusters V and IV were similar for salinity, they were distinct on temperature gradients, being found in cooler and in warmer temperatures, respectively. The differentiation of phylotype populations along the salinity and temporal gradients in Chesapeake Bay revealed distinct niches inhabited by different phylotypes of Bacteriovorax and unique estuarine phylotypes.


Assuntos
Baías/microbiologia , Deltaproteobacteria/classificação , Deltaproteobacteria/isolamento & purificação , Água do Mar/microbiologia , Baías/química , Deltaproteobacteria/genética , Deltaproteobacteria/metabolismo , Maryland , Dados de Sequência Molecular , Filogenia , Salinidade , Água do Mar/química , Cloreto de Sódio/análise , Cloreto de Sódio/metabolismo
7.
Proc Natl Acad Sci U S A ; 107(33): 14685-90, 2010 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-20679201

RESUMO

Drought exerts a strong influence on tropical forest metabolism, carbon stocks, and ultimately the flux of carbon to the atmosphere. Satellite-based studies have suggested that Amazon forests green up during droughts because of increased sunlight, whereas field studies have reported increased tree mortality during severe droughts. In an effort to reconcile these apparently conflicting findings, we conducted an analysis of climate data, field measurements, and improved satellite-based measures of forest photosynthetic activity. Wet-season precipitation and plant-available water (PAW) decreased over the Amazon Basin from 1996-2005, and photosynthetically active radiation (PAR) and air dryness (expressed as vapor pressure deficit, VPD) increased from 2002-2005. Using improved enhanced vegetation index (EVI) measurements (2000-2008), we show that gross primary productivity (expressed as EVI) declined with VPD and PAW in regions of sparse canopy cover across a wide range of environments for each year of the study. In densely forested areas, no climatic variable adequately explained the Basin-wide interannual variability of EVI. Based on a site-specific study, we show that monthly EVI was relatively insensitive to leaf area index (LAI) but correlated positively with leaf flushing and PAR measured in the field. These findings suggest that production of new leaves, even when unaccompanied by associated changes in LAI, could play an important role in Basin-wide interannual EVI variability. Because EVI variability was greatest in regions of lower PAW, we hypothesize that drought could increase EVI by synchronizing leaf flushing via its effects on leaf bud development.


Assuntos
Ecossistema , Estações do Ano , Árvores/crescimento & desenvolvimento , Clima Tropical , Geografia , Fotossíntese/efeitos dos fármacos , Fotossíntese/efeitos da radiação , Folhas de Planta/crescimento & desenvolvimento , Chuva , Luz Solar , Água/farmacologia
8.
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
9.
Ecology ; 92(3): 765-76, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21608484

RESUMO

Spatial resource subsidies can greatly affect the composition and dynamics of recipient communities. Caves are especially tractable for studying spatial subsidies because primary productivity is absent. Here, we performed an ecosystem-level manipulation experiment to test the direct influence of detrital subsidies on community structure in terrestrial cave ecosystems. After performing baseline censuses of invertebrates, we removed all organic material from 12 caves and constructed exclusion boxes to prevent natural resource inputs. Next, we stocked each cave with standardized quantities of two major natural subsidies to caves: leaves (leaf packs) and carcasses (commercially supplied rodents), and measured the invertebrate colonization and utilization of these resources for 23 months. Over the course of the experiment, 102 morphospecies were observed. Diplopods and collembolans were most abundant on leaf packs, and dipteran larvae and collembolans were most abundant on the rats. On average, caves receiving either treatment did not differ in species richness, but abundance was significantly higher in rat caves over both the duration of the experiment and the temporal "life" of the individual resources, which were restocked upon exhaustion. Post-manipulation invertebrate communities differed predictably depending on the type of subsidy introduced. Over the course of the experiment, caves that received the same subsidy clustered together based on community composition. In addition, the invertebrate community utilizing the resource changed over the duration of the two-year experiment, and evidence of succession (i.e., directional change) was observed. Results from this study demonstrate how allochthonous resources can drive the community dynamics of terrestrial invertebrates in cave ecosystems and highlight the need for consideration of the surface environment when managing and protecting these unique habitats.


Assuntos
Ecossistema , Invertebrados/fisiologia , Animais , Fenômenos Geológicos , Fatores de Tempo , West Virginia
10.
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
11.
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
12.
Ecology ; 91(5): 1257-62, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20503858

RESUMO

Since the early 1990s, morbidity and mortality in tortoise populations have been associated with a transmissible, mycoplasmal upper respiratory tract disease (URTD). Although the etiology, transmission, and diagnosis of URTD have been extensively studied, little is known about the dynamics of disease transmission in free-ranging tortoise populations. To understand the transmission dynamics of Mycoplasma agassizii, the primary etiological agent of URTD in wild tortoise populations, we studied 11 populations of free-ranging gopher tortoises (Gopherus polyphemus; n = 1667 individuals) over five years and determined their exposure to the pathogen by serology, by clinical signs, and by detection of the pathogen in nasal lavages. Adults tortoises (n = 759) were 11 times more likely to be seropositive than immature animals (n = 242) (odds ratio = 10.6, 95% CI = 5.7-20, P < 0.0001). Nasal discharge was observed in only 1.4% (4/296) of immature tortoises as compared with 8.6% (120/1399) of adult tortoises. Nasal lavages from all juvenile tortoises (n = 283) were negative by PCR for mycoplasmal pathogens associated with URTD. We tested for spatial segregation among tortoise burrows by size class and found no consistent evidence of clustering of either juveniles or adults. We suggest that the social behavior of tortoises plays a critical role in the spread of URTD in wild populations, with immature tortoises having minimal interactions with adult tortoises, thereby limiting their exposure to the pathogen. These findings may have broader implications for modeling horizontally transmitted diseases in other species with limited parental care and emphasize the importance of incorporating animal behavior parameters into disease transmission studies to better characterize the host-pathogen dynamics.


Assuntos
Infecções por Mycoplasma/veterinária , Infecções Respiratórias/veterinária , Comportamento Social , Tartarugas , Animais , Conservação dos Recursos Naturais , Florida , Infecções por Mycoplasma/transmissão , Infecções Respiratórias/microbiologia , Infecções Respiratórias/transmissão
13.
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)
14.
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
15.
J Acad Nutr Diet ; 120(4): 500-516.e10, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32199523

RESUMO

BACKGROUND: Higher protein intakes may help reduce sarcopenia and facilitate recovery from illness and injury in older adults. However, high-protein diets (HPDs) including animal-sourced foods may negatively perturb the microbiota, and provision of probiotics and prebiotics may mitigate these effects. OBJECTIVE: The aim of this study was to examine the effects of HPD, with and without a probiotic and/or prebiotic, on gut microbiota and wellness in older women. DESIGN: We conducted an 18-week, double-blind, placebo-controlled, crossover study. PARTICIPANTS/SETTING: Participants were healthy, older women (mean age±standard deviation=73.7±5.6 years; n=26) recruited from Florida. INTERVENTION: Participants received a weight-maintenance HPD for 2-week periods and the following, in random order: HPD alone (1.5 to 2.2 g/kg/day protein); HPD plus multistrain probiotic formulation (1.54×109Bifidobacterium bifidum HA-132, 4.62×109Bifidobacterium breve HA-129, 4.62×109Bifidobacterium longum HA-135, 4.62×109Lactobacillus acidophilus HA-122, and 4.62×109Lactobacillus plantarum HA-119), HPD plus prebiotic (5.6 g inulin), and HPD plus synbiotic (probiotic plus inulin), separated by 2-week washouts. Stools were collected per period for quantitative polymerase chain reaction (strain recovery) and 16S ribosomal RNA gene amplicon sequencing analyses (microbiota profile). Measures of gastrointestinal and general wellness were assessed. MAIN OUTCOME MEASURES: Microbiota composition and probiotic strain recovery were measured. STATISTICAL ANALYSES: Microbiota composition was analyzed by Wilcoxon signed-rank test and t test. Secondary outcomes were analyzing using generalized linear mixed models. RESULTS: The microbiota profile demonstrated relative stability with the HPD; representation of Lactobacillus, Lactococcus, and Streptococcus were enhanced, whereas butyrate producers, Roseburia and Anaerostipes, were suppressed. Lactococcus was suppressed with synbiotic vs other HPD periods. Recovery was confirmed for all probiotic strains. Indicators of wellness were unchanged, with the exception of a minimal increase in gastrointestinal distress with inulin. Fat-free mass increased from baseline to study end. CONCLUSIONS: An HPD adhering to the recommended acceptable macronutrient distribution ranges maintains wellness in healthy older women and exerts minor perturbations to the microbiome profile, a group that may benefit from a higher protein intake. ClinicalTrials.gov ID: NCT #02445560.


Assuntos
Dieta Rica em Proteínas/métodos , Microbioma Gastrointestinal/fisiologia , Trato Gastrointestinal/microbiologia , Prebióticos/administração & dosagem , Probióticos/administração & dosagem , Simbióticos/administração & dosagem , Idoso , Estudos Cross-Over , Método Duplo-Cego , Fenômenos Fisiológicos da Nutrição do Idoso , Feminino , Voluntários Saudáveis , Humanos
16.
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.

17.
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
18.
Sci Rep ; 7(1): 1641, 2017 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-28487533

RESUMO

Citrus black spot (CBS) caused by Phyllosticta citricarpa, is the most recent introduction of an exotic citrus pathogen into Florida and has been a challenge to control to date. Understanding the dispersal pattern of the disease within affected groves is vital in developing effective control strategies to limit the spread of the disease. The spatial pattern of CBS-affected trees was studied in two commercial 'Valencia' orange groves over three consecutive citrus seasons. Cluster analyses based on nearest-neighbor distance (F, G and J-functions) and pairwise distances between points (Ripley's K function, Besag's L function and the pair correlation function, g) were used to test the hypothesis of complete spatial randomness (CSR) of CBS infected trees within the groves. In both groves, the hypothesis of CSR was rejected for all tests performed including quadrats testing (2 × 2 trees up to 10 × 10 trees). The relationship between tree age and disease was assessed at one experimental site. Citrus trees bearing fruit for the first time accounted for approximately 13% of trees positive for disease and were located within areas of heavy disease pressure. These findings support short distance movement of inoculum as the main spread of disease in the groves studied.


Assuntos
Ascomicetos/fisiologia , Citrus/microbiologia , Doenças das Plantas/microbiologia , Análise Espaço-Temporal , Árvores/microbiologia , Florida , Frutas/crescimento & desenvolvimento , Reconhecimento Automatizado de Padrão , Chuva , Tamanho da Amostra , Tempo (Meteorologia)
19.
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
20.
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.

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