Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 68
Filtrar
1.
Appl Environ Microbiol ; 90(9): e0080924, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39189737

RESUMEN

This study describes the discovery and characterization of raffinocyclicin, a novel plasmid-encoded circular bacteriocin, produced by the raw milk isolate Lactococcus raffinolactis APC 3967. This bacteriocin has a molecular mass of 6,092 Da and contains 61 amino acids with a three-amino acid leader peptide. It shows the highest identity to the circular bacteriocins bacicyclicin XIN-1 (42.62%), aureocyclicin 4185 (42.62%), and garvicin ML (41.53%). A broad inhibitory spectrum includes strains from Staphylococcus, Enterococcus, Streptococcus, Micrococcus, Lactobacillus, Leuconostoc, and Listeria, in addition to a pronounced inhibitory effect against Lactococcus and Clostridium. It displays low sensitivity to trypsin, most likely as a result of its circular nature. The raffinocyclicin gene cluster is composed of 10 genes: 6 core genes, genes encoding an accessory three-component ABC transporter (rafCDE), and a putative transcriptional regulator related to the MutR family. A lack of inhibitory activity in the cell-free supernatant combined with the pronounced activity of cell extracts suggests that the majority of raffinocyclicin is associated with the cell rather than being released to the extracellular environment. This is the first report of a bacteriocin produced by the L. raffinolactis species.IMPORTANCEThe present study aimed to characterize raffinocyclicin, a novel circular bacteriocin produced by the lactic acid bacteria Lactococcus raffinolactis APC 3967. Bacteriocins are generally cationic and hydrophobic peptides with antimicrobial activity, which present diverse biotechnological properties of interest for the food industry. Raffinocyclicin inhibits a wide range of bacteria, including foodborne pathogens, and is stable against different treatments which suggest its potential as a natural biopreservative. Whole-genome sequencing and the genetic analysis of the raffinocyclicin gene cluster showed that it is encoded by plasmid that could be used in the future to transfer the ability to produce the bacteriocin to other lactic acid bacteria for industrial applications. These results together highlight the potential of this novel antimicrobial as a biopreservative to be used by the food industry.


Asunto(s)
Antibacterianos , Bacteriocinas , Lactococcus , Bacteriocinas/genética , Bacteriocinas/farmacología , Bacteriocinas/metabolismo , Lactococcus/genética , Lactococcus/metabolismo , Antibacterianos/farmacología , Plásmidos/genética , Microbiología de Alimentos , Bacterias Grampositivas/efectos de los fármacos , Bacterias Grampositivas/genética , Familia de Multigenes , Animales
2.
J Am Coll Health ; : 1-7, 2023 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-37856475

RESUMEN

Aim: This study explored the relationship between impostor phenomenon (IP), campus connectedness, self-compassion, and mental health among Black female undergraduate students attending an HBCU. Methods: Participants completed study measures via an online survey platform. Results: Linear regression analyses identified statistically significant relationships between campus connectedness, self-compassion, feelings of IP, and symptoms of depression, anxiety, and stress. Hierarchical regression analyses revealed that both self-compassion and campus connectedness explained statistically significant variance in mental health after controlling for the influence of IP on students' anxiety and depressive symptoms. Conclusion: Implications of this finding suggest student support services could develop and utilize programs that educate students about self-compassion interventions in order to decrease IP, which is directly linked with depression and anxiety.

3.
Int J Syst Evol Microbiol ; 73(10)2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37877999

RESUMEN

A novel bacterial strain, APC 3343T, was isolated from the intestine of a deep-sea loosejaw dragon fish, Malacosteus niger, caught at a depth of 1000 m in the Northwest Atlantic Ocean. Cells were aerobic, rod-shaped, yellow/orange-pigmented, non-motile and Gram-negative. Growth of strain APC 3343T was observed at 4-30 °C (optimum, 21-25 °C), pH 5.5-10 (optimum, pH 7-8) and 0.5-8 % (w/v) NaCl (optimum, 2-4 %). Phylogenetic analysis based on 16S rRNA gene sequences showed that strain APC 3343T was most closely related to members of the genus Winogradskyella, with the most closely related type strains being Winogradskyella algae Kr9-9T (98.46 % identity), Winogradskyella damuponensis F081-2T (98.07 %), Winogradskyella eximia CECT 7946T (97.93 %), Winogradskyella litoriviva KMM 6491T (97.79 %) and Winogradskyella endarachnes HL2-2T (97.79 %). Major fatty acids (>10 % of total) were iso-C16 : 0 3-OH, iso-C15 : 0, anteiso-C15 : 0 and iso-C17 : 0 3-OH. The predominant respiratory quinone was menaquinone-6 (MK-6). Polar lipids were phosphatidylethanolamine, three unknown aminolipids and eight unknown lipids. The draft genome sequence was 3.8 Mb in length with a G+C content of 33.43 mol%. Based on the phenotypic characteristics and phylogenetic analysis, strain APC 3343T is deemed to be a novel species of the genus Winogradskyella, and for which the name Winogradskyella bathintestinalis sp. nov. is proposed. The type strain of this species is APC 3343T (=DSM 115832T=NCIMB 15464T).


Asunto(s)
Ácidos Grasos , Perciformes , Animales , Niger , Filogenia , ARN Ribosómico 16S/genética , Composición de Base , Ácidos Grasos/química , Análisis de Secuencia de ADN , ADN Bacteriano/genética , Técnicas de Tipificación Bacteriana , Peces , Intestinos
4.
Foods ; 12(7)2023 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-37048292

RESUMEN

Vibrios, such as Vibrio parahaemolyticus, are naturally occurring halophilic bacteria that are a major cause of foodborne illness. Because of their autochthonous nature, managing vibrio levels in marine and estuarine environments is impossible. Instead, it is crucial to reliably enumerate their abundance to minimize human exposure. One method of achieving this is the direct plating/colony hybridization (DP/CH) method, which has been used to efficiently quantify pathogenic vibrios in oysters and other seafood products. Although successful, the method relies on proprietary resources. We examined alternative approaches, assessed the influence of the reagent suppliers' source on enumeration accuracy, and made experimental adjustments that maximized efficiency, sensitivity, and specificity. We report here that in-house conjugation via Cell Mosaic is a viable alternative to the previously available sole-source distributor of the alkaline phosphatase-conjugated probes used to enumerate vibrios in oysters. We also report that milk was a viable alternative as a blocking reagent, pH must be eight, an orbital shaker was a viable alternative to a water bath, and narrow polypropylene containers were a viable alternative to Whirl-Pak bags. These modifications will be crucial to scientists enumerating vibrios and other pathogens in food products.

5.
Mol Ecol ; 32(12): 3322-3339, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36906957

RESUMEN

The gut microbiota have important consequences for host biological processes and there is some evidence that they also affect fitness. However, the complex, interactive nature of ecological factors that influence the gut microbiota has scarcely been investigated in natural populations. We sampled the gut microbiota of wild great tits (Parus major) at different life stages allowing us to evaluate how microbiota varied with respect to a diverse range of key ecological factors of two broad types: (1) host state, namely age and sex, and the life history variables, timing of breeding, fecundity and reproductive success; and (2) the environment, including habitat type, the distance of the nest to the woodland edge, and the general nest and woodland site environments. The gut microbiota varied with life history and the environment in many ways that were largely dependent on age. Nestlings were far more sensitive to environmental variation than adults, pointing to a high degree of flexibility at an important time in development. As nestlings developed their microbiota from one to two weeks of life, they retained consistent (i.e., repeatable) among-individual differences. However these apparent individual differences were driven entirely by the effect of sharing the same nest. Our findings point to important early windows during development in which the gut microbiota are most sensitive to a variety of environmental drivers at multiple scales, and suggest reproductive timing, and hence potentially parental quality or food availability, are linked with the microbiota. Identifying and explicating the various ecological sources that shape an individual's gut bacteria is of vital importance for understanding the gut microbiota's role in animal fitness.


Asunto(s)
Microbioma Gastrointestinal , Microbiota , Passeriformes , Animales , Microbioma Gastrointestinal/genética , Bacterias , Fertilidad
6.
PLoS One ; 18(2): e0280205, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36780434

RESUMEN

INTRODUCTION: Situational judgment tests have been adopted by medical schools to assess decision-making and ethical characteristics of applicants. These tests are hypothesized to positively affect diversity in admissions by serving as a noncognitive metric of evaluation. The purpose of this study was to evaluate the performance of the Computer-based Assessment for Sampling Personal Characteristics (CASPer) scores in relation to admissions interview evaluations. METHODS: This was a cohort study of applicants interviewing at a public school of medicine in the southeastern United States in 2018 and 2019. Applicants took the CASPer test prior to their interview day. In-person interviews consisted of a traditional interview and multiple-mini-interview (MMI) stations. Between subjects, analyses were used to compare scores from traditional interviews, MMIs, and CASPer across race, ethnicity, and gender. RESULTS: 1,237 applicants were interviewed (2018: n = 608; 2019: n = 629). Fifty-seven percent identified as female. Self-identified race/ethnicity included 758 White, 118 Black or African-American, 296 Asian, 20 Native American or Alaskan Native, 1 Native Hawaiian or Other Pacific Islander, and 44 No response; 87 applicants identified as Hispanic. Black or African-American, Native American or Alaskan Native, and Hispanic applicants had significantly lower CASPer scores than other applicants. Statistically significant differences in CASPer percentiles were identified for gender and race; however, between subjects, comparisons were not significant. CONCLUSIONS: The CASPer test showed disparate scores across racial and ethnic groups in this cohort study and may not contribute to minimizing bias in medical school admissions.


Asunto(s)
Juicio , Facultades de Medicina , Humanos , Femenino , Estados Unidos , Estudios de Cohortes , Criterios de Admisión Escolar , Etnicidad
7.
Endocr Pract ; 29(1): 29-32, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36280026

RESUMEN

OBJECTIVE: Recent advances in technology have allowed for the expanded use of hybrid closed-loop insulin pump therapy and automated insulin delivery systems for the management of diabetes mellitus. We assessed the outcomes of introducing Tandem t:slim X2 with the Control-IQ technology in a general endocrine clinic. METHODS: Data from 66 adults with type 1 (n = 61) and type 2 (n = 5) diabetes mellitus were aggregated for analysis. Patients were either transitioned from traditional insulin pump therapy or multiple daily injection therapy to Tandem t:slim X2 with the Control-IQ technology from January 2020 to June 2021. The assessed clinical end points included changes in time below range, time above range, and time in target range. Changes in hemoglobin A1C before and after Control-IQ technology implementation were noted. The primary outcome was a change in time in target range with the Control-IQ technology. RESULTS: There was a significant increase in time in target range when comparing pre- and post-Control-IQ technology (49.5% vs 63.3%, P < .0003) values. There was a reduction in time above range (46.8% vs 34.9%, P < .0013), a decrease in time below range (4.0% vs 1.7%, P = .017), and a decrease in hemoglobin A1C after transitioning to the Control-IQ technology (7.7% [61 mmol/mol] vs 7.1% [54 mmol/mol], P < .017). The patient dropout rate was low (7%). CONCLUSION: The Control-IQ technology system was effective in reducing hyperglycemia while increasing time in target range and decreasing hypoglycemia. This technology is a useful and effective addition to the growing number of automated insulin delivery systems. The clinical outcomes mirror the results found in the key adult pivotal trials.


Asunto(s)
Diabetes Mellitus Tipo 1 , Hipoglucemiantes , Adulto , Humanos , Glucemia , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Hemoglobina Glucada , Insulina , Sistemas de Infusión de Insulina , Automonitorización de la Glucosa Sanguínea/métodos , Tecnología , Estudios Cruzados
8.
Sci Rep ; 12(1): 20904, 2022 12 03.
Artículo en Inglés | MEDLINE | ID: mdl-36463255

RESUMEN

Bacterial communities associated with vegetation-soil interfaces have important roles in terrestrial ecosystems. These bacterial communities, studied almost exclusively in unburnt ecosystems or those affected by rare, high-intensity wildfires, have been understudied in fire-frequented grasslands and savannas. The composition of ground-level bacterial communities was explored in an old-growth pine savanna with a centuries-long management history of prescribed fires every 1-2 years. Using 16S metabarcoding, hypotheses were tested regarding differences in bacterial families of litter and soil surface substrates in patches of ground layer vegetation that were naturally burnt or unburnt during landscape-level prescribed fires. Litter/soil substrates and fire/no fire treatments explained 67.5% of bacterial community variation and differences, driven by relative abundance shifts of specific bacterial families. Fires did not strongly affect plant or soil variables, which were not linked to bacterial community differences. Litter/soil substrates and the naturally patchy frequent fires appear to generate microhabitat heterogeneity in this pine savanna, driving responses of bacterial families. Prescribed fire management may benefit from considering how fire-altered substrate heterogeneity influences and maintains microbial diversity and function, especially in these fiery ecosystems. Frequent, low-intensity fires appear ecologically important in maintaining the diverse microbial foundation that underlie ecosystem processes and services in fire-frequented habitats.


Asunto(s)
Incendios , Pinus , Ecosistema , Pradera , Suelo
9.
Depress Anxiety ; 39(5): 397-406, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35389536

RESUMEN

BACKGROUND: Repetitive transcranial magnetic stimulation (rTMS) is an effective treatment for major depressive disorder (MDD). Psychostimulant medication use may be associated with improved rTMS outcomes, but a detailed understanding of these relationships is lacking. METHODS: We compared MDD subjects taking psychostimulants (n = 37) with those not taking one of these medications (n = 53) during a course of 30 rTMS treatments. Changes in the 30-item Inventory of Depressive Symptomatology Self Report (IDS-SR30) subscale scores were examined at treatment 30. We also subdivided subjects into three categories based on drug mechanism and looked at IDS-SR30 total score after treatments 10, 20, and 30. RESULTS: Subjects taking psychostimulants had a significantly greater overall clinical improvement than those not taking these medications at treatment 30. The psychostimulant group also improved significantly more than the control group in "sleep" and "mood/cognition," but not "anxiety/arousal" IDS-SR30 subscales. No differences were detected among individual drug categories, which may reflect the limited sample size for individual medications. There was a negative dose-response relationship for the lisdexamfetamine/dextroamphetamine group, in which lower doses were associated with better clinical outcome. CONCLUSIONS: Psychostimulant medications may enhance clinical efficacy of rTMS for MDD by preferentially impacting specific symptom domains. For some psychostimulants, these effects may be dose-dependent. Prospective clinical trials are needed to guide psychostimulant augmentation of brain stimulation therapies.


Asunto(s)
Trastorno Depresivo Mayor , Trastorno Depresivo Mayor/diagnóstico , Humanos , Corteza Prefrontal/fisiología , Estudios Prospectivos , Estimulación Magnética Transcraneal , Resultado del Tratamiento
10.
Diabetes Spectr ; 35(1): 8-15, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-35308147

RESUMEN

This article reviews the current diabetes technology landscape and how recent advancements are being used to help overcome barriers in the management of diabetes. The authors offer case examples of how digital tools and platforms can facilitate diabetes care via telehealth and remote patient monitoring for individuals in special populations. They also provide tips to ensure success in implementing diabetes technology to provide the best possible care for people with diabetes in outpatient settings.

11.
J Diabetes Sci Technol ; 16(3): 659-662, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-33430621

RESUMEN

BACKGROUND: Hybrid closed-loop (HCL) insulin pump therapy (Medtronic 670G) is an emerging technology that is growing in use worldwide. Initial clinical trials demonstrated the effectiveness of HCL in reducing hypoglycemia and improving glucose control; however, these subjects were intensely monitored and supervised. There has been concern regarding the ability of patients to remain in auto mode. We aimed to assess HCL when used in a typical outpatient endocrine clinic. METHODS: We initially analyzed data from 80 individuals with type 1 diabetes managed in an endocrine clinic by a single certified diabetes educator (CDE). We then included our other providers and had 230 subjects by the end of the study. Patients were either transitioned from traditional insulin pump or multiple daily insulin injection therapy (MDI) to HCL. Patients initiated to HCL pump therapy from July 2017 through February 2020 were studied. Endpoints of change in time in hypoglycemic/hyperglycemic range and time in target range were analyzed. The primary outcome was a change in percent time in the target range during manual mode compared with auto mode. RESULTS: There was an 18.2% increase in average time in target range when comparing manual mode to auto mode (59.3% vs 70.1%, P < .0001). Average time in hyperglycemic range was significantly reduced by 26.7% (39.0% vs 28.6%, P < .0001) but without increasing average time in hypoglycemic range (1.7% vs 1.3%, P = 0.95). CONCLUSIONS: HCL was effective in reducing hyperglycemia and increasing time in the target range but did not increase hypoglycemia. These data suggest HCL will improve the metrics of glucose control.


Asunto(s)
Diabetes Mellitus Tipo 1 , Hipoglucemia , Glucemia , Automonitorización de la Glucosa Sanguínea , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Humanos , Hipoglucemia/inducido químicamente , Hipoglucemia/tratamiento farmacológico , Hipoglucemia/prevención & control , Hipoglucemiantes/uso terapéutico , Insulina/uso terapéutico , Sistemas de Infusión de Insulina
12.
Front Mol Biosci ; 8: 654038, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33996906

RESUMEN

Staphylococcus aureus is a pathogen commonly found in nosocomial environments where infections can easily spread - especially given the reduced immune response of patients and large overlap between personnel in charge of their care. Although antibiotics are available to treat nosocomial infections, the increased occurrence of antibiotic resistance has rendered many treatments ineffective. Such is the case for methicillin resistant S. aureus (MRSA), which has continued to be a threat to public health since its emergence. For this reason, alternative treatment technologies utilizing antimicrobials such as bacteriocins, bacteriophages (phages) and phage endolysins are being developed. These antimicrobials provide an advantage over antibiotics in that many have narrow inhibition spectra, enabling treatments to be selected based on the target (pathogenic) bacterium while allowing for survival of commensal bacteria and thus avoiding collateral damage to the microbiome. Bacterial resistance to these treatments occurs less frequently than with antibiotics, particularly in circumstances where combinatory antimicrobial therapies are used. Phage therapy has been well established in Eastern Europe as an effective treatment against bacterial infections. While there are no Randomized Clinical Trials (RCTs) to our knowledge examining phage treatment of S. aureus infections that have completed all trial phases, numerous clinical trials are underway, and several commercial phage preparations are currently available to treat S. aureus infections. Bacteriocins have primarily been used in the food industry for bio-preservation applications. However, the idea of repurposing bacteriocins for human health is an attractive one considering their efficacy against many bacterial pathogens. There are concerns about the ability of bacteriocins to survive the gastrointestinal tract given their proteinaceous nature, however, this obstacle may be overcome by altering the administration route of the therapy through encapsulation, or by bioengineering protease-resistant variants. Obstacles such as enzymatic digestion are less of an issue for topical/local administration, for example, application to the surface of the skin. Bacteriocins have also shown impressive synergistic effects when used in conjunction with other antimicrobials, including antibiotics, which may allow antibiotic-based therapies to be used more sparingly with less resistance development. This review provides an updated account of known bacteriocins, phages and phage endolysins which have demonstrated an impressive ability to kill S. aureus strains. In particular, examples of antimicrobials with the ability to target MRSA strains and their subsequent use in a clinical setting are outlined.

13.
Eur J Nutr ; 60(8): 4393-4411, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34057578

RESUMEN

PURPOSE: Brewers' spent grain (BSG) represents the largest by-product of the brewing industry. Its utilisation as an animal feed has become less practical today; however, its high fibre and protein content make it a promising untapped resource for human nutrition. BSG contains mainly insoluble fibre. This fibre, along with protein, is trapped with the complex lignocellulosic cell structure and must be solubilised to release components which may be beneficial to health through modulation of the gut microbiota. METHODS: In this study, the application of a simultaneous saccharification and fermentation process for the extraction and solubilisation of arabinoxylan from BSG is demonstrated. RESULTS: Processing of the BSG was varied to modulate the physicochemical and molecular characteristic of the released arabinoxylan. The maximum level of arabinoxylan solubilisation achieved was approximately 21%, compared to the unprocessed BSG which contained no soluble arabinoxylan (AX). Concentration of the solubilised material produced a sample containing 99% soluble AX. Samples were investigated for their microbiome modulating capacity in in-vitro faecal fermentation trials. Many samples promoted increased Lactobacillus levels (approx. twofold). One sample that contained the highest level of soluble AX was shown to be bifidogenic, increasing the levels of this genus approx. 3.5-fold as well as acetate (p = 0.018) and propionate (p < 0.001) production. CONCLUSION: The findings indicate that AX extracted from BSG has prebiotic potential. The demonstration that BSG is a source of functional fibre is a promising step towards the application of this brewing side-stream as a functional food ingredient for human nutrition.


Asunto(s)
Grano Comestible , Microbiota , Animales , Fermentación , Humanos , Xilanos
14.
J Anim Ecol ; 90(4): 989-1003, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33481278

RESUMEN

Natal body mass is a key predictor of viability and fitness in many animals. While variation in body mass and therefore juvenile viability may be explained by genetic and environmental factors, emerging evidence points to the gut microbiota as an important factor influencing host health. The gut microbiota is known to change during development, but it remains unclear whether the microbiome predicts fitness, and if it does, at which developmental stage it affects fitness traits. We collected data on two traits associated with fitness in wild nestling great tits Parus major: weight and survival to fledging. We characterised the gut microbiome using 16S rRNA sequencing from nestling faeces and investigated temporal associations between the gut microbiome and fitness traits across development at Day-8 (D8) and Day-15 (D15) post-hatching. We also explored whether particular microbial taxa were 'indicator species' that reflected whether nestlings survived or not. There was no link between mass and microbial diversity on D8 or D15. However, we detected a time-lagged relationship where weight at D15 was negatively associated with the microbial diversity at D8, controlling for weight at D8, therefore reflecting relative weight gain over the intervening period. Indicator species analysis revealed that specificity values were high and fidelity values were low, suggesting that indicator taxa were primarily detected within either the survived or not survived groups, but not always detected in birds that either survived or died. Therefore these indicator taxa may be sufficient, but not necessary for determining either survival or mortality, perhaps owing to functional overlap in microbiota. We highlight that measuring microbiome-fitness relationships at just one time point may be misleading, especially early in life. Instead, microbial-host fitness effects may be best investigated longitudinally to detect critical development windows for key microbiota and host traits associated with neonatal weight. Our findings should inform future hypothesis testing to pinpoint which features of the gut microbial community impact on host fitness, and when during development this occurs. Such confirmatory research will shed light on population level processes and could have the potential to support conservation.


Asunto(s)
Microbioma Gastrointestinal , Microbiota , Passeriformes , Animales , Peso Corporal , ARN Ribosómico 16S/genética
15.
Toxicol Pathol ; 48(8): 965-980, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33334257

RESUMEN

It is well established that hexachlorophene, which is used as an antibacterial agent, causes intramyelinic edema in humans and animal models. The hexachlorophene myelinopathy model, in which male Sprague-Dawley rats received 25 to 30 mg/kg hexachlorophene by gavage for up to 5 days, provided an opportunity to compare traditional neuropathology evaluations with magnetic resonance microscopy (MRM) findings. In addition, stereology assessments of 3 neuroanatomical sites were compared to quantitative measurements of similar structures by MRM. There were positive correlations between hematoxylin and eosin and luxol fast blue stains and MRM for identifying intramyelinic edema in the cingulum of corpus callosum, optic chiasm, anterior commissure (aca), lateral olfactory tracts, pyramidal tracts (py), and white matter tracts in the cerebellum. Stereology assessments were focused on the aca, longitudinal fasciculus of the pons, and py and demonstrated differences between control and treated rats, as was observed using MRM. The added value of MRM assessments was the ability to acquire qualitative 3-dimensional (3-D) images and obtain quantitative measurements of intramyelinic edema in 26 neuroanatomical sites in the intact brain. Also, diffusion tensor imaging (fractional anisotropy [FA]) indicated that there were changes in the cytoarchitecture of the white matter as detected by decreases in the FA in the treated compared to the control rats. This study demonstrates creative strategies that are possible using qualitative and quantitative assessments of potential white matter neurotoxicants in nonclinical toxicity studies. Our results lead us to the conclusion that volumetric analysis by MRM and stereology adds significant value to the standard 2-D microscopic evaluations.


Asunto(s)
Imagen de Difusión Tensora , Hexaclorofeno , Animales , Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Masculino , Microscopía , Ratas , Ratas Sprague-Dawley
16.
Sci Rep ; 10(1): 20783, 2020 11 27.
Artículo en Inglés | MEDLINE | ID: mdl-33247162

RESUMEN

The microbial community in the gut is influenced by environmental factors, especially diet, which can moderate host behaviour through the microbiome-gut-brain axis. However, the ecological relevance of microbiome-mediated behavioural plasticity in wild animals is unknown. We presented wild-caught great tits (Parus major) with a problem-solving task and showed that performance was weakly associated with variation in the gut microbiome. We then manipulated the gut microbiome by feeding birds one of two diets that differed in their relative levels of fat, protein and fibre content: an insect diet (low content), or a seed diet (high content). Microbial communities were less diverse among individuals given the insect compared to those on the seed diet. Individuals were less likely to problem-solve after being given the insect diet, and the same microbiota metrics that were altered as a consequence of diet were also those that correlated with variation in problem solving performance. Although the effect on problem-solving behaviour could have been caused by motivational or nutritional differences between our treatments, our results nevertheless raise the possibility that dietary induced changes in the gut microbiota could be an important mechanism underlying individual behavioural plasticity in wild populations.


Asunto(s)
Conducta Animal/fisiología , Dieta , Microbioma Gastrointestinal , Passeriformes/microbiología , Passeriformes/fisiología , Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Animales Salvajes/microbiología , Animales Salvajes/fisiología , Animales Salvajes/psicología , Biodiversidad , Ecosistema , Femenino , Microbioma Gastrointestinal/genética , Microbioma Gastrointestinal/fisiología , Irlanda , Masculino , Solución de Problemas/fisiología , ARN Ribosómico 16S/genética
17.
Toxicol Pathol ; 48(6): 747-755, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32815483

RESUMEN

The National Toxicology Program (NTP) now uses an extended longitudinal sectioning protocol for the uterus to better evaluate female rodent reproductive tract toxicity for all developmental and reproductive toxicology and 2-year toxicity and carcinogenicity bioassays. The previous protocol for toxicity/carcinogenicity studies involved 1 cross section midway through each uterine horn and collection of uterine cervix and vagina only if gross lesions were present. Here we compare the histological findings of the original cross sections with the additional longitudinal sections of residual uterine tissues of 7 chronic NTP rat bioassays. The goal of this study was to determine whether there might be any advantages to examining additional uterine tissue. The longitudinal protocol allowed for 10 to 20 times more uterine tissue for evaluation. Results indicate that the potential advantages of a more complete evaluation of female reproductive tract tissue include increased detection of reproductive targets, increased detection of neoplastic and nonneoplastic lesions, improved detection of tissue origin of neoplasms, less reliance on gross identification of lesions, improved accuracy in the application of severity grades, and increased detection of preneoplastic or subtle lesions.


Asunto(s)
Neoplasias , Reproducción , Animales , Bioensayo , Pruebas de Carcinogenicidad , Femenino , Técnicas Histológicas , Ratas , Útero
18.
Am J Physiol Heart Circ Physiol ; 318(3): H590-H603, 2020 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-32031871

RESUMEN

Metabolic syndrome (MetS) is a composite of cardiometabolic risk factors, including obesity, dyslipidemia, hypertension, and insulin resistance, with a range of secondary sequelae such as nonalcoholic fatty liver disease and diastolic heart failure. This syndrome has been identified as one of the greatest global health challenges of the 21st century. Herein, we examine whether a porcine model of diet- and mineralocorticoid-induced MetS closely mimics the cardiovascular, metabolic, gut microbiota, and functional metataxonomic phenotype observed in human studies. Landrace pigs with deoxycorticosterone acetate-induced hypertension fed a diet high in fat, salt, and sugar over 12 wk were assessed for hyperlipidemia, hyperinsulinemia, and immunohistologic, echocardiographic, and hemodynamic parameters, as well as assessed for microbiome phenotype and function through 16S rRNA metataxonomic and metabolomic analysis, respectively. All MetS animals developed obesity, hyperlipidemia, insulin resistance, hypertension, fatty liver, structural cardiovascular changes including left ventricular hypertrophy and left atrial enlargement, and increased circulating saturated fatty acid levels, all in keeping with the human phenotype. A reduction in α-diversity and specific microbiota changes at phylum, family, and genus levels were also observed in this model. Specifically, this porcine model of MetS displayed increased abundances of proinflammatory bacteria coupled with increased circulating tumor necrosis factor-α and increased secondary bile acid-producing bacteria, which substantially impacted fibroblast growth factor-19 expression. Finally, a significant decrease in enteroprotective bacteria and a reduction in short-chain fatty acid-producing bacteria were also noted. Together, these data suggest that diet and mineralocorticoid-mediated development of biochemical and cardiovascular stigmata of metabolic syndrome in pigs leads to temporal gut microbiome changes that mimic key gut microbial population signatures in human cardiometabolic disease.NEW & NOTEWORTHY This study extends a prior porcine model of cardiometabolic syndrome to include systemic inflammation, fatty liver, and insulin sensitivity. Gut microbiome changes during evolution of porcine cardiometabolic disease recapitulate those in human subjects with alterations in gut taxa associated with proinflammatory bacteria, bile acid, and fatty acid pathways. This clinical scale model may facilitate design of future interventional trials to test causal relationships between gut dysbiosis and cardiometabolic syndrome at a systemic and organ level.


Asunto(s)
Microbioma Gastrointestinal/fisiología , Hipertensión/microbiología , Resistencia a la Insulina/fisiología , Síndrome Metabólico/microbiología , Enfermedad del Hígado Graso no Alcohólico/microbiología , Animales , Glucemia/metabolismo , Colesterol/sangre , Dieta Alta en Grasa , Modelos Animales de Enfermedad , Ecocardiografía , Femenino , Hipertensión/metabolismo , Inflamación/metabolismo , Inflamación/microbiología , Insulina/sangre , Síndrome Metabólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Porcinos , Triglicéridos/sangre
19.
Artículo en Inglés | MEDLINE | ID: mdl-31783489

RESUMEN

There is a need to develop novel complementary interventions aimed at enhancing treatment engagement and/or response for veterans with psychiatric and substance use disorders. There is evidence that both mindfulness training and nature exposure (MT/NE) may be beneficial for this population and that combining the two approaches into one intervention might result in synergistic benefit. However, to date, the MT/NE concept has not been tested. This article reports a pilot feasibility and acceptability study of MT/NE which was, in this case, provided via recreational sailing. The primary aim of this project was to develop a model intervention and evaluation process that could be used for future studies of MT/NE interventions using a variety of methods of nature exposure (e.g., hiking, skiing, mountain biking). Results indicate preliminary evidence that it is feasible to utilize MT/NE interventions for the population studied and that the MT/NE model described can serve as a template for future investigations. Further, there were significant pre- to post-intervention decreases in state anxiety, as well as increases in trait mindfulness. Three psychological instruments were identified that might be used in future studies to evaluate MT/NE outcomes. Results from this project provide a model MT/NE intervention template along with evaluation metrics for use in future studies.


Asunto(s)
Trastornos Mentales/rehabilitación , Atención Plena , Trastornos Relacionados con Sustancias/rehabilitación , Veteranos , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Atención Plena/métodos , Naturaleza , Proyectos Piloto , Resultado del Tratamiento , Veteranos/psicología
20.
J Am Assoc Lab Anim Sci ; 58(4): 510-516, 2019 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-31068243

RESUMEN

Elizabethan collars (E-collars) are commonly used in various species to safeguard healing wounds. However, E-collars inadvertently restrict the expression of normal species-typical behaviors, including coprophagy, self-grooming, and social housing. To maintain social housing in accordance with recommendations in the 8th edition of the Guide for the Care and Use of Laboratory Animals, we implemented the use of human infant pants instead of E-collars for postsurgical protection. We retrospectively reviewed the medical records of 154 intact male New Zealand white rabbits (age, 2 to 3 mo) regarding the use of E-collars (group 1; n = 72) compared with human infant pants (group 2; n = 82) for postoperative protection after 308 femoral angioplasty procedures. Maintenance of social pairs throughout the postoperative phase, replacement rate of infant pants, and self-mutilation rates were measured. Our findings indicate that using infant pants for postoperative protection was most successful in maintaining social housing, offers a more cost-effective option to E-collars, and does not increase the rate of self-mutilation in intact male New Zealand white rabbits.


Asunto(s)
Bienestar del Animal , Animales de Laboratorio , Vivienda para Animales , Periodo Posoperatorio , Equipos de Seguridad/veterinaria , Conejos/cirugía , Animales , Vestuario , Humanos , Masculino , Estudios Retrospectivos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA