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1.
Nature ; 613(7945): 639-649, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36697862

RESUMEN

Whether the human fetus and the prenatal intrauterine environment (amniotic fluid and placenta) are stably colonized by microbial communities in a healthy pregnancy remains a subject of debate. Here we evaluate recent studies that characterized microbial populations in human fetuses from the perspectives of reproductive biology, microbial ecology, bioinformatics, immunology, clinical microbiology and gnotobiology, and assess possible mechanisms by which the fetus might interact with microorganisms. Our analysis indicates that the detected microbial signals are likely the result of contamination during the clinical procedures to obtain fetal samples or during DNA extraction and DNA sequencing. Furthermore, the existence of live and replicating microbial populations in healthy fetal tissues is not compatible with fundamental concepts of immunology, clinical microbiology and the derivation of germ-free mammals. These conclusions are important to our understanding of human immune development and illustrate common pitfalls in the microbial analyses of many other low-biomass environments. The pursuit of a fetal microbiome serves as a cautionary example of the challenges of sequence-based microbiome studies when biomass is low or absent, and emphasizes the need for a trans-disciplinary approach that goes beyond contamination controls by also incorporating biological, ecological and mechanistic concepts.


Asunto(s)
Biomasa , Contaminación de ADN , Feto , Microbiota , Animales , Femenino , Humanos , Embarazo , Líquido Amniótico/inmunología , Líquido Amniótico/microbiología , Mamíferos , Microbiota/genética , Placenta/inmunología , Placenta/microbiología , Feto/inmunología , Feto/microbiología , Reproducibilidad de los Resultados
2.
Immunity ; 43(5): 998-1010, 2015 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-26522986

RESUMEN

Intestinal helminths are potent regulators of their host's immune system and can ameliorate inflammatory diseases such as allergic asthma. In the present study we have assessed whether this anti-inflammatory activity was purely intrinsic to helminths, or whether it also involved crosstalk with the local microbiota. We report that chronic infection with the murine helminth Heligmosomoides polygyrus bakeri (Hpb) altered the intestinal habitat, allowing increased short chain fatty acid (SCFA) production. Transfer of the Hpb-modified microbiota alone was sufficient to mediate protection against allergic asthma. The helminth-induced anti-inflammatory cytokine secretion and regulatory T cell suppressor activity that mediated the protection required the G protein-coupled receptor (GPR)-41. A similar alteration in the metabolic potential of intestinal bacterial communities was observed with diverse parasitic and host species, suggesting that this represents an evolutionary conserved mechanism of host-microbe-helminth interactions.


Asunto(s)
Microbioma Gastrointestinal/inmunología , Helmintos/inmunología , Hipersensibilidad/inmunología , Inflamación/inmunología , Inflamación/parasitología , Mucosa Intestinal/inmunología , Mucosa Intestinal/microbiología , Adulto , Anciano , Animales , Asma/inmunología , Asma/microbiología , Asma/parasitología , Citocinas/inmunología , Ácidos Grasos/inmunología , Femenino , Humanos , Hipersensibilidad/microbiología , Hipersensibilidad/parasitología , Inflamación/microbiología , Mucosa Intestinal/parasitología , Masculino , Ratones , Ratones Endogámicos C57BL , Persona de Mediana Edad , Nematospiroides dubius/inmunología , Receptores Acoplados a Proteínas G/inmunología , Infecciones por Strongylida/inmunología , Infecciones por Strongylida/microbiología , Infecciones por Strongylida/parasitología
3.
Eur J Appl Physiol ; 124(6): 1895-1910, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38236302

RESUMEN

INTRODUCTION: Ironman triathletes undergo high workloads during competition preparation which can result in nonfunctional overreaching or overtraining syndrome if not matched with adequate recovery. PURPOSE: The purpose of this case study was to observe changes in physiological and psychological status over the course of a competitive season in a free-living triathlete. METHODS: The subject was a 41-year-old triathlete competing in three 113.1-km events. Over the course of a 40-week period, the participant arrived at the laboratory every 4 weeks and underwent body composition testing via air displacement plethysmography, a blood draw for analysis of various biomarkers, and a treadmill-based lactate threshold test. Workload during training and competitions was monitored via a wearable heart rate-monitoring device. RESULTS: Throughout the season, training volume remained high (12.5 ± 3.4 h/week) and body mass and fat-free mass (FFM) continuously decreased, while biomarkers including cortisol, testosterone, and markers of immunological status exhibited minor changes. Laboratory performance remained relatively consistent, while competition performance continually improved. Following the completion of the competitive period, training volume decreased, FFM remained below baseline levels, free cortisol increased, and both free and total testosterone decreased. CONCLUSIONS: Workload and recovery seem to have been properly managed throughout the season, evidenced by minimal fluctuations in endocrine and immunological markers. The reason for changes observed in testosterone, cortisol, and body composition following the last competition is unclear, though it may be attributed to changes in stressors and recovery practices outside of training. It is recommended that athletes follow a structured plan during the transition period into the offseason to ensure recovery of physiological state and to set up a productive offseason.


Asunto(s)
Rendimiento Atlético , Biomarcadores , Humanos , Biomarcadores/sangre , Adulto , Masculino , Rendimiento Atlético/fisiología , Atletas , Testosterona/sangre , Hidrocortisona/sangre , Carrera/fisiología , Ciclismo/fisiología , Composición Corporal/fisiología , Conducta Competitiva/fisiología , Acondicionamiento Físico Humano/fisiología , Acondicionamiento Físico Humano/métodos , Frecuencia Cardíaca/fisiología
4.
J Strength Cond Res ; 37(7): 1428-1433, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-36727935

RESUMEN

ABSTRACT: McFadden, BA, Bozzini, BN, Cintineo, HP, Hills, SP, Walker, AJ, Chandler, AJ, Sanders, DJ, Russell, M, and Arent, SM. Power, endurance, and body composition changes over a collegiate career in National Collegiate Athletic Association Division I women soccer athletes. J Strength Cond Res 37(7): 1428-1433, 2023-The purpose of this study was to determine longitudinal changes in fitness and body composition throughout athletes' 4-year collegiate soccer careers. Performance testing occurred before preseason during freshman, sophomore, junior, and senior year in 17 female Division I soccer players. Body composition was assessed through air-displacement plethysmography to determine percent body fat (%BF), fat-free mass (FFM), and body mass (BM). Maximal countermovement vertical jump height was assessed through contact mat using arm swing (CMJ AS ) and hands-on-hips (CMJ HOH ) methods to calculate power (CMJ watts / HOHwatts ). Aerobic capacity (V̇ o2 max) and ventilatory threshold (VT) were assessed by indirect calorimetry during a maximal graded exercise test on a treadmill. Linear mixed models were used to assess changes across academic years ( p < 0.05). No changes occurred in %BF, BM, V̇ o2 max, VT, CMJ AS , or CMJ watts . A time main effect was seen for FFM ( p = 0.01) with increases from freshman to senior ( p = 0.02). Time main effects were observed for CMJ HOH ( p < 0.001) and CMJ HOHwatts ( p < 0.001) with increases from freshman to junior (CMJ HOH,p = 0.001; CMJ HOHwatts , p = 0.02) and senior (CMJ HOH , p < 0.001; CMJ HOHwatts , p = 0.003) as well as sophomore to senior (CMJ HOH , p < 0.001; CMJ HOHwatts , p = 0.02). Countermovement vertical jump with hands on hips also increased from sophomore to junior ( p = 0.005). The lower FFM and power capabilities as freshmen compared with upperclassman indicate a potential limited readiness. Coaches and training staff should account for these developmental differences when entering the preseason. Adequate conditioning programs before starting a collegiate program may help build a fitness foundation and prepare freshmen athletes to compete at the same level as their upperclassmen counterparts.


Asunto(s)
Rendimiento Atlético , Fútbol , Deportes , Femenino , Humanos , Ejercicio Físico , Composición Corporal , Atletas
5.
J Strength Cond Res ; 36(5): 1373-1382, 2022 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-34100786

RESUMEN

ABSTRACT: McFadden, BA, Walker, AJ, Bozzini, BN, Hofacker, M, Russell, M, and Arent, SM. Psychological and physiological changes in response to the cumulative demands of a women's division I collegiate soccer season. J Strength Cond Res 36(5): 1373-1382, 2022-This study sought to determine the effects of a women's collegiate soccer season on psychological markers, biomarkers, sleep, and performance. Athletes participated in maximal countermovement vertical jump height (CMJ) assessments and biomarker monitoring in conjunction with subjective measures of psychological wellness and sleep questionnaires before preseason (S1) and every 4 weeks following (S2, S3, and S4). Training was monitored during practices and games using global positioning satellite systems and heart rate technology. Total training load was highest from S1 to S2, decreased from S2 to S3 (effect size [ES] = -2.5; p < 0.001), and remained stable from S3 to S4. CMJ declined at S2 (ES1-2 = -0.51; p = 0.001) and returned to baseline at S3. Increases from S1 to S2 were seen for creatine kinase (ES1-2 = 1.74), free testosterone (ES1-2 = 1.27), total testosterone (ES1-2 = 3.5), and free cortisol (ES1-2 = 0.88) (p < 0.03) before returning to baseline by S3 and S4 (free cortisol). Total cortisol was elevated throughout the season before declining at S4 (ES1-4 = -0.41; p = 0.03). Iron declined from S1 to S2 (ES1-2 = -0.73; p = 0.01) and returned to baseline values at S4, whereas growth hormone declined at S2 (ES1-2 = -0.50; p = 0.01) and remained depressed. Interleukin-6 increased at S4 (ES1-4 = 0.71; p = 0.02). Total training distress decreased from S1 to S2 (ES1-2 = -0.38; p = 0.02), returned to baseline by S3, and increased by S4 (ES1-4 = 0.57; p = 0.01). No changes were observed in markers of sleep (p > 0.05). Biomarkers showed notable changes after the highest workload period (S1-S2), which coincided with CMJ decrements. Biomarker perturbations preceded declines in subjective psychological wellness (S4) which occurred in the latter half of the season, indicating an accumulation of fatigue as the season progressed.


Asunto(s)
Fútbol , Biomarcadores , Femenino , Humanos , Hidrocortisona , Estaciones del Año , Fútbol/fisiología , Testosterona
6.
J Gerontol Nurs ; 48(6): 7-11, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35648578

RESUMEN

China is increasingly turning to community care (CC) to fill the growing gap between the care needs of older adults and availability of that care. The specific application of this concept in China takes two forms: state cash-for-care programs and a market-oriented operational approach. State cash-for-care programs offer cash payments or vouchers, and older adults have a statutory entitlement to apply for the relief of CC charges. The market-oriented operational model comprises urban community care service "supermarkets," where older adults can buy services according to their needs. Even with these two programs, CC still has many shortcomings. Deficits include lack of national standards for individual services and personnel development, and absence of an independent department or systems to oversee supervision and quality assessment. This policy brief offers key recommendations for government investment through supportive social policies and improvements to the quantity and quality of the care workforce. [Journal of Gerontological Nursing, 48(6), 7-11.].


Asunto(s)
Política Pública , Anciano , China , Humanos , Recursos Humanos
7.
Int J Intercult Relat ; 88: 83-94, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35492377

RESUMEN

While the ensuing COVID-19 pandemic has significantly altered individuals' lives worldwide, it has been perhaps especially disruptive to the lives of sojourners as many have been unable to return home and are absent from their families, a familiar culture, and normal social support systems. While it is important to ask how such individuals can successfully survive in such a crisis, we were interested in extending our knowledge and understanding by asking "how can such individuals move beyond mere surviving to a state of thriving?" In answering this question, we utilized a positive psychology framework to develop a theoretical model wherein we expected higher/lower levels of perceived social support from host country people (i.e., host country support) to result in higher/lower levels of perceived gratitude, which would then result in higher/lower levels of thriving, and ethnocentrism moderated this indirect effect. To test our model, we utilized a sample of sojourners who responded to a survey measuring ethnocentrism (February 2020). We then administered daily surveys measuring perceived host country support, gratitude, and thriving over a nine-day period during the COVID-19 crisis (March 26-April 3, 2020). Results supported the indirect effect of host country support on thriving via gratitude. Further, we found that sojourners with lower levels of ethnocentrism exhibited stronger host country support- gratitude link, hence stronger indirect effect of host country support on thriving via gratitude. We close by offering implications for the existing literature, future research, and organizational practices.

8.
Immunity ; 37(4): 674-84, 2012 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-23063332

RESUMEN

Mice lacking the transcription factor T-bet in the innate immune system develop microbiota-dependent colitis. Here, we show that interleukin-17A (IL-17A)-producing IL-7Rα(+) innate lymphoid cells (ILCs) were potent promoters of disease in Tbx21(-/-)Rag2(-/-) ulcerative colitis (TRUC) mice. TNF-α produced by CD103(-)CD11b(+) dendritic cells synergized with IL-23 to drive IL-17A production by ILCs, demonstrating a previously unrecognized layer of cellular crosstalk between dendritic cells and ILCs. We have identified Helicobacter typhlonius as a key disease trigger driving excess TNF-α production and promoting colitis in TRUC mice. Crucially, T-bet also suppressed the expression of IL-7R, a key molecule involved in controlling intestinal ILC homeostasis. The importance of IL-7R signaling in TRUC disease was highlighted by the dramatic reduction in intestinal ILCs and attenuated colitis following IL-7R blockade. Taken together, these data demonstrate the mechanism by which T-bet regulates the complex interplay between mucosal dendritic cells, ILCs, and the intestinal microbiota.


Asunto(s)
Colitis Ulcerosa/inmunología , Proteínas de Unión al ADN/inmunología , Inmunidad Innata , Linfocitos/inmunología , Receptores de Interleucina-7/inmunología , Proteínas de Dominio T Box/inmunología , Animales , Células Cultivadas , Enfermedad Crónica , Colitis Ulcerosa/microbiología , Colitis Ulcerosa/patología , Proteínas de Unión al ADN/deficiencia , Helicobacter/inmunología , Ratones , Ratones Endogámicos BALB C , Ratones Noqueados , Transducción de Señal , Proteínas de Dominio T Box/deficiencia
9.
Artículo en Inglés | MEDLINE | ID: mdl-34398726

RESUMEN

A strictly anaerobic, resistant starch-degrading, bile-tolerant, autolytic strain, IPLA60002T, belonging to the family Ruminococcaceae, was isolated from a human bile sample of a liver donor without hepatobiliary disease. Cells were Gram-stain-positive cocci, and 16S rRNA gene and whole genome analyses showed that Ruminococcus bromii was the phylogenetically closest related species to the novel strain IPLA60002T, though with average nucleotide identity values below 90 %. Biochemically, the new isolate has metabolic features similar to those described previously for gut R. bromii strains, including the ability to degrade a range of different starches. The new isolate, however, produces lactate and shows distinct resistance to the presence of bile salts. Additionally, the novel bile isolate displays an autolytic phenotype after growing in different media. Strain IPLA60002T is phylogenetically distinct from other species within the genus Ruminococcus. Therefore, we propose on the basis of phylogenetic, genomic and metabolic data that the novel IPLA60002T strain isolated from human bile be given the name Ruminococcoides bili gen. nov., sp. nov., within the new proposed genus Ruminococcoides and the family Ruminococcaceae. Strain IPLA60002T (=DSM 110008T=LMG 31505T) is proposed as the type strain of Ruminococcoides bili.


Asunto(s)
Bilis/microbiología , Filogenia , Ruminococcus/clasificación , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Humanos , ARN Ribosómico 16S/genética , Ruminococcus/aislamiento & purificación , Análisis de Secuencia de ADN
10.
J Fish Biol ; 99(4): 1201-1221, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34085709

RESUMEN

This study quantifies the processes involved in regulating the European eel population of Lough Neagh, a lake in Northern Ireland. The relationship between glass eel input and silver eel output for the 1923-1997 cohorts was best described by a Beverton-Holt stock recruitment model. Glass eel input time series was not complete and was thus derived from the relationship between catches elsewhere in Europe and Lough Neagh, together with the addition of stocked glass eel. Silver eel output was the sum of silver eel escapement, catch and yellow eel catch converted to silver eel equivalents. Natural mortality increased with glass eel density, ranging from 0.017 to 0.142 year-1 . The mean carrying capacity increased from ≈3.25 M silver eels (≈26 kg ha-1 ) for the 1923-1943 cohorts to ≈5.0 M (≈40 kg ha-1 ) for the 1948-1971 cohorts before regressing back to ≈3.25 M. The total silver eel output was highest during the late 1970s/early 1980s at 35-45 kg ha-1  year-1 and lowest during the early years of the 20th century and is currently at 10-15 kg ha-1  year-1 . The findings are discussed in relation to (a) the ecological changes that have occurred within the lough, associated with eutrophication and the introduction of roach (Rutilus rutilus L.), and (b) the decline of the wider European eel stock across its distribution range. The findings from this study have relevance for the wider management of the European eel stock.


Asunto(s)
Anguilla , Animales , Conservación de los Recursos Naturales , Europa (Continente) , Lagos , Irlanda del Norte
11.
J Strength Cond Res ; 35(8): 2316-2320, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-30908370

RESUMEN

ABSTRACT: Sanders, DJ, Walker, AJ, Prior, KE, Poyssick, AN, and Arent, SM. Training demands and physiological profile of cross-disciplined collegiate female dancers. J Strength Cond Res 35(8): 2316-2320, 2021-Little is known about the physical demands of high-level dance training. Therefore, the purpose of this study was to investigate the physiological demands of a typical ballet and modern class through training load (TL) and to assess differences in TL between the 2 class types. In addition, a physiological profile of cross-disciplined collegiate female dancers was determined. Seventeen college-aged female dancers were recruited and performed a battery of performance tests assessing body fat (%BF), lean body mass, vertical jump (VJ), peak power, maximal oxygen consumption (V̇o2max), and ventilatory threshold (VT). Two ballet and modern dance classes were monitored for TL and exercise energy expenditure (EEE) using the Polar Team2 Pro System. Performance testing results were as follows: M%BF = 24.1 ± 4.2%, MLBM = 46.8 ± 8.5 kg, MV̇o2max = 42.9 ± 4.3 ml·kg-1·min-1, MVT = 76.2 ± 6.5% of V̇o2max, MVJ = 44.1 ± 1.4 cm, and MPP = 519.1 ± 177.5 W. Training load of 41.0 ± 17.0 for ballet and 44.8 ± 27.4 for modern dance was found, with an EEE of 394.0 ± 111.9 and 421.9 ± 161.4 kcal, respectively. Time spent at or above VT was 1.2 ± 2.6 minutes in ballet and 3.4 ± 8.3 minutes in modern. Compared with other female power-endurance athletes, the dancers accumulated a much lower TL during both class types. Low TL may inhibit typical adaptations seen in other athletes, which may explain why dancers in this study had lower aerobic and anaerobic capacities and higher body fat percentage than other collegiate female athletes. Also, it suggests that supplemental conditioning could be incorporated into a dancers training paradigm to optimize performance.


Asunto(s)
Baile , Consumo de Oxígeno , Atletas , Composición Corporal , Ejercicio Físico , Femenino , Humanos , Adulto Joven
12.
J Strength Cond Res ; 35(5): 1326-1330, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33677462

RESUMEN

ABSTRACT: Sekiguchi, Y, Curtis, RM, Huggins, RA, Benjamin, CL, Walker, AJ, Arent, SM, Adams, WM, Anderson, T, and Casa, DJ. The relationships between perceived wellness of, sleep of, and acute: chronic training load on National Collegiate Athletics Association division I male soccer players. J Strength Cond Res 35(5): 1326-1330, 2021-The purpose of this study was to investigate relationships between perceived wellness, sleep, and acute: chronic workload ratio (ACWR) throughout a collegiate men's soccer season. Sixty male collegiate soccer players (mean[M] ± SD; age, 21±2 year; body mass, 77.6 ± 6.5 kg; height, 180.1 ± 6.4 cm; body fat%, 9.9 ± 3.9% ; and V̇o2max, 53.1 ± 5.0 ml·kg-1·min-1) participated in this study. During each session, players used a heart rate and global positioning satellite-enabled chest strap to measure training impulse and ACWR. The ACWR values were trichotomized at the individual level giving an equal number of observations within each ACWR category of low, moderate, and high ACWR (M ± SD; low, 0.658 ± 0.23; moderate, 0.92 ± 0.15; and high, 1.17 ± 0.16). Stress, fatigue, and soreness levels were collected using 1-10 Likert scales and sleep duration, and sleep quality were measured by the Karolinska Sleep Diary. Stress, fatigue, soreness levels, and sleep quality were transformed to corresponding z-scores at the individual level. Fatigue levels were significantly higher when ACWR was high compared with low (mean difference [95% confidence intervals], effect size, p-value; 0.31 [0.21, 0.42], 0.29, p < 0.001) and moderate (0.14 [0.03, 0.24], 0.13, p = 0.01). Fatigue levels were also significantly higher when the ACWR was moderate compared with low (0.18 [0.07, 0.28], 0.16, p = 0.001). Soreness levels were significantly higher when the ACWR was high compared with low (0.25 [0.14, 0.36], 0.23, p < 0.001). Stress levels were significantly greater when the ACWR was high compared with low (0.19, [0.08, 0.29], 0.18, p < 0.001) and compared with moderate (0.15, [0.05, 0.25], 0.14, p = 0.004). There were no differences in sleep duration or sleep quality in different ACWR. The ACWR may be a useful tool to achieve an appropriate balance between training and recovery to manage daily fatigue and soreness levels in athletes.


Asunto(s)
Fútbol , Adulto , Atletas , Fatiga , Humanos , Masculino , Sueño , Universidades , Adulto Joven
13.
BMC Microbiol ; 20(1): 283, 2020 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-32928123

RESUMEN

BACKGROUND: The human colon is colonised by a dense microbial community whose species composition and metabolism are linked to health and disease. The main energy sources for colonic bacteria are dietary polysaccharides and oligosaccharides. These play a major role in modulating gut microbial composition and metabolism, which in turn can impact on health outcomes. RESULTS: We investigated the influence of wheat bran arabinoxylan oligosaccharides (AXOS) and maltodextrin supplements in modulating the composition of the colonic microbiota and metabolites in healthy adults over the age of 60. Male and female volunteers, (n = 21, mean BMI 25.2 ± 0.7 kg/m2) participated in the double-blind, cross over supplement study. Faecal samples were collected for analysis of microbiota, short chain fatty acids levels and calprotectin. Blood samples were collected to measure glucose, cholesterol and triglycerides levels. There was no change in these markers nor in calprotectin levels in response to the supplements. Both supplements were well-tolerated by the volunteers. Microbiota analysis across the whole volunteer cohort revealed a significant increase in the proportional abundance of faecal Bifidobacterium species (P ≤ 0.01) in response to AXOS, but not maltodextrin, supplementation. There was considerable inter-individual variation in the other bacterial taxa that responded, with a clear stratification of volunteers as either Prevotella-plus (n = 8; > 0.1% proportional abundance) or Prevotella-minus (n = 13; ≤0.1% proportional abundance) subjects founded on baseline sample profiles. There was a significant increase in the proportional abundance of both faecal Bifidobacterium (P ≤ 0.01) and Prevotella species (P ≤ 0.01) in Prevotella-plus volunteers during AXOS supplementation, while Prevotella and Bacteroides relative abundances showed an inverse relationship. Proportional abundance of 26 OTUs, including bifidobacteria and Anaerostipes hadrus, differed significantly between baseline samples of Prevotella-plus compared to Prevotella-minus individuals. CONCLUSIONS: The wheat bran AXOS supplementation was bifidogenic and resulted in changes in human gut microbiota composition that depended on the initial microbiota profile, specifically the presence or absence of Prevotella spp. as a major component of the microbiota. Our data therefore suggest that initial profiling of individuals through gut microbiota analysis should be considered important when contemplating nutritional interventions that rely on prebiotics. TRIAL REGISTRATION: Clinical trial registration number: NCT02693782 . Registered 29 February 2016 - Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT02693782?term=NCT02693782&rank=1.


Asunto(s)
Fibras de la Dieta , Microbioma Gastrointestinal/fisiología , Oligosacáridos/farmacología , Prevotella/fisiología , Anciano , Suplementos Dietéticos , Método Doble Ciego , Ácidos Grasos Volátiles/metabolismo , Heces/química , Heces/microbiología , Femenino , Microbioma Gastrointestinal/efectos de los fármacos , Humanos , Complejo de Antígeno L1 de Leucocito/análisis , Lípidos/sangre , Masculino , Persona de Mediana Edad , Oligosacáridos/química , Polisacáridos/farmacología , Prebióticos , Prevotella/efectos de los fármacos , Xilanos
14.
Med Mycol ; 58(6): 744-755, 2020 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-31912151

RESUMEN

Candida auris is an emerging pathogenic yeast of significant clinical concern because of its frequent intrinsic resistance to fluconazole and often other antifungal drugs and the high mortality rates associated with systemic infections. Furthermore, C. auris has a propensity for persistence and transmission in health care environments. The reasons for this efficient transmission are not well understood, and therefore we tested whether enhanced resistance to environmental stresses might contribute to the ability of C. auris to spread in health care environments. We compared C. auris to other pathogenic Candida species with respect to their resistance to individual stresses and combinations of stresses. Stress resistance was examined using in vitro assays on laboratory media and also on hospital linen. In general, the 17 C. auris isolates examined displayed similar degrees of resistance to oxidative, nitrosative, cationic and cell wall stresses as clinical isolates of C. albicans, C. glabrata, C. tropicalis, C. parapsilosis, C. krusei, C. guilliermondii, C. lusitaniae and C. kefyr. All of the C. auris isolates examined were more sensitive to low pH (pH 2, but not pH 4) compared to C. albicans, but were more resistant to high pH (pH 13). C. auris was also sensitive to low pH, when tested on contaminated hospital linen. Most C. auris isolates were relatively thermotolerant, displaying significant growth at 47°C. Furthermore, C. auris was relatively resistant to certain combinations of combinatorial stress (e.g., pH 13 plus 47°C). Significantly, C. auris was sensitive to the stress combinations imposed by hospital laundering protocol (pH > 12 plus heat shock at >80°C), suggesting that current laundering procedures are sufficient to limit the transmission of this fungal pathogen via hospital linen.


Asunto(s)
Candida/patogenicidad , Candidiasis/transmisión , Ambiente , Hospitales , Estrés Fisiológico , Antifúngicos/farmacología , Ropa de Cama y Ropa Blanca/microbiología , Candida/clasificación , Candida/efectos de los fármacos , Candidiasis/microbiología , Farmacorresistencia Fúngica , Equipos y Suministros de Hospitales/microbiología , Humanos , Concentración de Iones de Hidrógeno , Pruebas de Sensibilidad Microbiana , Estrés Nitrosativo , Estrés Oxidativo , Termotolerancia
15.
J Strength Cond Res ; 34(12): 3364-3368, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33021584

RESUMEN

Bozzini, BN, McFadden, BA, Walker, AJ, and Arent, SM. Varying demands and quality of play between in-conference and out-of-conference games in Division I collegiate women's soccer. J Strength Cond Res 34(12): 3364-3368, 2020-The purpose of this study was to assess differences in physical workloads, physiological responses, and performance variables between in-conference (IC) and out-of-conference (OC) games during a collegiate women's soccer season. Female field players (N = 11), who played a minimum of 45 minutes for >50% of games, were evaluated using an integrative GPS and HR monitoring system to determine training load (TL), exercise energy expenditure (EEE), total distance covered (DIS), sprints, time spent in HR zones 4 and 5 (HRZ4 = 80-89% HRmax; HRZ5 = 90-100% HRmax), and distance covered in speed zones 4 and 5 (DISZ4 = 15.0-19.9 km·h; DISZ5 = ≥20 km·h). In addition, percent passing accuracy (PA%), dribbling success (DS%), tackling success (TS%), and challenges won (CW%) were generated for all games. Workload data were analyzed as a rate per minute playing time (PT) per game to account for differences in game duration and PT between OC (n = 7) and IC games (n = 11). Repeated-measures multivariate analyses of variance with univariate follow-ups and effect sizes (Hedges' g) were conducted to compare conditions (OC vs. CON) (p < 0.05). There were significantly greater TL, DIS, EEE, and HRZ5 per minute PT in OC versus IC games (Hedges' g: TL = 0.48; DIS = 0.20, EEE = 0.55; HRZ5 = 0.83; p < 0.05). Further analysis found significant differences in first half play favoring OC games (p < 0.05), but not second half play (p > 0.05). Based on these findings, OC games seem to be more demanding compared to IC, particularly during first half play. Emphasis should be placed on tailoring TL to the accumulating in-season demands through athlete-monitoring technology to prevent declines in performance in the latter half of the season.


Asunto(s)
Rendimiento Atlético , Carrera , Fútbol , Atletas , Ejercicio Físico , Femenino , Humanos
16.
J Strength Cond Res ; 34(4): 969-974, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31972824

RESUMEN

McFadden, BA, Walker, AJ, Bozzini, BN, Sanders, DJ, and Arent, SM. Comparison of internal and external training loads in male and female collegiate soccer players during practices vs. games. J Strength Cond Res 34(4): 969-974, 2020-The purpose of this study was to compare the internal and external training loads (TLs) in men and women throughout a Division I soccer season during practices versus games. Players were evaluated during all practices and regulation game play using the Polar TeamPro system, utilizing Global Positioning Satellite technology and heart rate (HR) monitoring to determine TL, time spent in HR zones expressed as a percent of HRmax (HRZ1-Z5), calories expended per kilogram body mass (Kcal·kg), distance covered (DIS), sprints, average speed (SPDAVG), and distance covered in speed zones (DISZ1-Z5). During games, no significant differences were seen between men and women for TL, Kcal·kg, HRZ1-Z5, SPDAVG, DIS, DISZ1, DISZ3, and DISZ4. However, men accumulated a significantly greater number of sprints and DISZ5 (p < 0.05) during games, whereas women accumulated a greater DISZ2 (p < 0.05). During practice, no differences were observed for TL, DIS, sprints, Kcal·kg, DISZ2, DISZ3, HRZ1-Z5, but men exhibited higher SPDAVG, (p < 0.05), DISZ1 (p < 0.05), DISZ4 (p < 0.05), and DISZ5 (p < 0.05). The parallels in Kcal·kg, total DIS, HR, and TL indicate a similar relative workload between men and women. However, distance covered in higher speed zones was found to be greater in men than women across practice and games likely reflecting inherent sex differences in the ability to achieve those speeds. Monitoring techniques that track relative player workloads throughout practices and games may enhance player health and performance during the season. An individualized approach to tracking high-intensity running may improve workload prescriptions on a per player basis.


Asunto(s)
Rendimiento Atlético/fisiología , Fútbol/fisiología , Adolescente , Metabolismo Energético/fisiología , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Carrera/fisiología , Factores Sexuales , Universidades , Adulto Joven
17.
J Strength Cond Res ; 34(4): 975-981, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31972829

RESUMEN

Walker, AJ, McFadden, BA, Sanders, DJ, Bozzini, BN, Conway, SP, and Arent, SM. Early season hormonal and biochemical changes in Division I field hockey players: is fitness protective? J Strength Cond Res 34(4): 975-981, 2020-The purpose was to evaluate changes in hormonal and biochemical markers as a result of the accumulated stress of the initial 4-week training block in field hockey players. Women's Division I field hockey players (N = 22; Mage = 19.7 ± 1.1 years) performed testing before the start of preseason (A1) that included body composition (%BF), vertical jump, and V[Combining Dot Above]O2max. Blood draws were conducted at A1 to assess creatine kinase (CK), iron (Fe), hemoglobin (HGB), hematocrit (HCT), percent saturation (%sat), total cortisol (TCORT), free cortisol (FCORT), interleukin-6 (IL-6), sex hormone-binding globulin (SHBG), prolactin (PRL), vitamin D (vitD), and thyroxine (T3). Blood draws were repeated 4 weeks later (A2). Athletes were monitored during this training block, which included 2 weeks of preseason and the first 2 weeks of the season, using heart rate monitors to determine energy expenditure (Kcal) and training load. There were significant disruptions in TCORT, FCORT, T3, CK, Fe, and SHBG (p < 0.05) from A1 to A2. V[Combining Dot Above]O2max accounted for 31% (p < 0.05) of the variance in TCORT and %BF accounting for an additional 20.1% (p < 0.05). V[Combining Dot Above]O2max accounted for 32.7% (p < 0.05) of the variance in FCORT. %BF accounted for 48.9% (p < 0.05) of the variance in T3. Kcal was positively correlated with V[Combining Dot Above]O2max (p < 0.05) and negatively correlated with %BF (p < 0.05). Athletes with higher V[Combining Dot Above]O2max and lower %BF may be capable of a higher work output and therefore more likely to experience increased physiological disruptions during intense training. The high-volume nature of preseason and differences in athlete fitness capabilities require coaches to manage players at an individual level to maintain athlete readiness.


Asunto(s)
Composición Corporal/fisiología , Hockey/fisiología , Estrés Fisiológico/fisiología , Atletas , Rendimiento Atlético/fisiología , Biomarcadores , Ejercicio Físico/fisiología , Femenino , Humanos , Consumo de Oxígeno/fisiología , Aptitud Física/fisiología , Globulina de Unión a Hormona Sexual , Adulto Joven
18.
J Strength Cond Res ; 34(2): 374-381, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31524781

RESUMEN

Curtis, RM, Huggins, RA, Benjamin, CL, Sekiguchi, Y, Adams, WM, Arent, SM, Jain, R, Miller, SJ, Walker, AJ, and Casa, DJ. Contextual factors influencing external and internal training loads in collegiate men's soccer. J Strength Cond Res 34(2): 374-381, 2020-This study investigated factors influencing training loads (TL) in collegiate men's soccer. Total distance, high-speed running distance (>14.4 km·h), high-intensity heart-rate zone duration (HI HRZ, >70% heart rate relative to maximum), and session rating of perceived exertion were assessed daily from 107 male soccer players competing for 5 National Collegiate Athletics Association Division I teams. Differences between athlete role (starter and reserve), position (defender, midfielder, and forward), season phase (preseason, in-season, and postseason), days relative to match (MD-1 to MD-5+), days between matches (<4, 4-5, >5 days), previous match outcome (win, loss, and draw), and upcoming opponent relative ranking (weaker, trivial, and stronger) were examined. Mean differences (MD) and effect sizes (ESs) with 90% confidence intervals were reported. There were trivial and insignificant differences by player role, position, or upcoming opponent strength, and small-moderate increases in preseason TL compared with in-season (ES [range] = 0.4-0.9). TLs were lower for MD-1 and higher for MD-5+ (ES [range] = 0.4-1.3) when compared with MD-2-4. External loads (ES = -0.40 ± 0.20) were less after wins compared with losses. TLs are increased in the preseason, when training sessions occur greater than 5 days from a match and after losses. Contextualizing factors affecting TLs has implications for developing workload prescription and recovery strategies.


Asunto(s)
Atletas , Acondicionamiento Físico Humano/fisiología , Fútbol/fisiología , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Esfuerzo Físico/fisiología , Carrera/fisiología , Universidades , Adulto Joven
19.
PLoS Pathog ; 13(7): e1006536, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28759611

RESUMEN

TPL-2 (COT, MAP3K8) kinase activates the MEK1/2-ERK1/2 MAPK signaling pathway in innate immune responses following TLR, TNFR1 and IL-1R stimulation. TPL-2 contributes to type-1/Th17-mediated autoimmunity and control of intracellular pathogens. We recently demonstrated TPL-2 reduces severe airway allergy to house dust mite by negatively regulating type-2 responses. In the present study, we found that TPL-2 deficiency resulted in resistance to Heligmosomoides polygyrus infection, with accelerated worm expulsion, reduced fecal egg burden and reduced worm fitness. Using co-housing experiments, we found resistance to infection in TPL-2 deficient mice (Map3k8-/-) was independent of microbiota alterations in H. polygyrus infected WT and Map3k8-/-mice. Additionally, our data demonstrated immunity to H. polygyrus infection in TPL-2 deficient mice was not due to dysregulated type-2 immune responses. Genome-wide analysis of intestinal tissue from infected TPL-2-deficient mice identified elevated expression of genes involved in chemotaxis and homing of leukocytes and cells, including Ccl24 and alternatively activated genes. Indeed, Map3k8-/-mice had a significant influx of eosinophils, neutrophils, monocytes and Il4GFP+ T cells. Conditional knockout experiments demonstrated that specific deletion of TPL-2 in CD11c+ cells, but not Villin+ epithelial cells, LysM+ myeloid cells or CD4+ T cells, led to accelerated resistance to H. polygyrus. In line with a central role of CD11c+ cells, CD11c+ CD11b+ cells isolated from TPL-2-deficient mice had elevated Ccl24. Finally, Ccl24 neutralization in TPL-2 deficient mice significantly decreased the expression of Arg1, Retnla, Chil3 and Ear11 correlating with a loss of resistance to H. polygyrus. These observations suggest that TPL-2-regulated Ccl24 in CD11c+CD11b+ cells prevents accelerated type-2 mediated immunity to H. polygyrus. Collectively, this study identifies a previously unappreciated role for TPL-2 controlling immune responses to H. polygyrus infection by restricting Ccl24 production.


Asunto(s)
Quimiocina CCL24/inmunología , Quinasas Quinasa Quinasa PAM/inmunología , Nematospiroides dubius/inmunología , Proteínas Proto-Oncogénicas/inmunología , Infecciones por Strongylida/inmunología , Animales , Quimiocina CCL24/genética , Femenino , Humanos , Inmunidad Innata , Quinasas Quinasa Quinasa PAM/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Nematospiroides dubius/genética , Nematospiroides dubius/fisiología , Proteínas Proto-Oncogénicas/genética , Infecciones por Strongylida/enzimología , Infecciones por Strongylida/genética , Infecciones por Strongylida/parasitología , Células Th2/inmunología
20.
BMC Biol ; 16(1): 134, 2018 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-30382878

RESUMEN

Alan Walker is a Senior Lecturer at the University of Aberdeen, UK, studying the intestinal microbiota and its interactions with the host's diet. In this interview, Alan discusses his research interests, earlier studies of the ways contaminants can affect microbiome analyses, the excitement of experiments going well, and why science doesn't need to be combative.


Asunto(s)
Microbioma Gastrointestinal/fisiología , Microbiología/historia , Animales , Dieta , Historia del Siglo XXI , Humanos , Escocia
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