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1.
J Dairy Sci ; 103(9): 8615-8628, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32684462

RESUMEN

The early development of immunity and microbiota in the gut of newborn calves can have life-long consequences. Gut microbiota and the intestinal barrier interplay after birth, establishing a homeostatic state whereby mucosal cells cohabit with microorganisms to develop a healthy gut. We hypothesized that postnatal codevelopment of gut immunity and microbiota could be influenced by early-life supplementation with live yeast. Starting from birth, calves either received a daily supplementation of Saccharomyces cerevisiae boulardii CNCM I-1079 (SCB, 10 × 109 cfu/d, n = 10) in the morning meal for 7 d or no supplementation (n = 10). Each animal received 2 adequate colostrum replacer meals at 2 and 12 h of life (expected total IgG fed = 300 g) before being fed milk replacer twice a day. Passive transfer of immunity (total protein, IgG, and IgA) through colostrum was evaluated and endogenous production of IgA was investigated by measuring IgA-producing plasma cells, IgA relative gene expression (PIGR and CD79A), and secretory IgA concentration in the gut. The concentration of targeted microbial groups was evaluated with quantitative PCR in the gut digesta collected at d 7 of life. Early SCB supplementation did not impair immunoglobulin absorption and all calves had successful passive transfer of immunity (serum IgG concentration >15 mg/mL at d 1 and d 7 of age). Although the expression of IgA relative gene expression (PIGR and CD79A) was not different, SCB calves had higher secretory IgA concentrations in the ileum (1.98 ± 0.12 mg/g of dry matter; DM) and colon (1.45 ± 0.12 mg/g of DM) digesta compared with control animals (1.18 and 0.59 ± 0.12 mg/g of DM, respectively). In addition, the number of IgA-producing plasma cells were greater in both ileum (2.55 ± 0.40 cells/mm2) and colon (3.03 ± 0.40 cells/mm2) tissues for SCB calves compared with control (respectively 1.00 ± 0.40 and 0.60 ± 0.42 cells/mm2). Endogenous IgA production in the gut of SCB calves was enhanced, which could make them less prone to pathogen intrusion. In addition, SCB calves had higher Lactobacillus and tended to have higher Faecalibacterium prausnitzii in the jejunum compared with control calves, which suggests that SCB supplementation during early-life gut colonization may have a positive effect in newborn calves. Direct SCB supplementation or the cross-talk between SCB and bacteria may be responsible for stimulating IgA production and may play a key role in shaping early colonization in the gut of newborn calves.


Asunto(s)
Animales Recién Nacidos , Íleon/efectos de los fármacos , Inmunoglobulina A/metabolismo , Saccharomyces cerevisiae , Levadura Seca , Animales , Bacterias/inmunología , Bacterias/metabolismo , Líquidos Corporales , Bovinos , Calostro/inmunología , Femenino , Microbioma Gastrointestinal , Inmunoglobulina G/sangre , Microbiota , Embarazo
2.
J Dairy Sci ; 102(8): 7011-7025, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31155261

RESUMEN

The objective of this study was to investigate the effect of one specific strain of yeast, Saccharomyces cerevisiae boulardii CNCM I-1079 (SCB), on the growth performance, health, and fecal bacterial profile of veal calves. A total of 84 animals were enrolled in an experiment at a commercial veal farm for a total of 7 wk. Calves were fed twice a day with a milk replacer meal during the entire experiment and were randomly assigned to receive daily either SCB supplementation (10 × 109 cfu/d) or a placebo (CON). Individual feed intake and body weight were monitored on a daily and weekly basis, respectively. Fecal samples were collected at arrival to the veal facility (wk 0) and additional samples were taken on d 14 (wk 2) and d 49 (wk 7). These samples were subjected to 16S rRNA gene amplicon sequencing using Illumina MiSeq (Illumina Inc., San Diego, CA) to examine the bacterial profiles and real-time quantitative PCR to quantify Saccharomyces cerevisiae and specific bacterial groups. The significant increase of S. cerevisiae in the feces of SCB calves at wk 2 and 7 compared with wk 0 (respectively 1.7 × 107, 1.2 × 107, and 2.2 × 105 copy number of S. cerevisiae/g of feces) indicates a good survival of that yeast strain along the gastrointestinal tract. Supplementation of SCB did not improve overall growth performance with regard to average daily gain (ADG), final body weight, and feed intake. Nevertheless, a total of 69.1% of nonsupplemented calves had diarrhea and 28.6% experienced severe diarrhea, whereas 50.0% of the calves supplemented with SCB had diarrhea and 9.5% experienced severe diarrhea. With respect to antibiotic use, 89.7% of the diarrheic calves recorded in the CON group were treated, whereas only 66.7% of the SCB diarrheic calves received an antibiotic. In addition, diarrheic calves supplemented with SCB maintained an ADG similar to nondiarrheic animals, whereas the CON diarrheic calves had a significantly lower ADG in comparison with nondiarrheic CON calves. Fecalibacterium was the most predominant bacterial genus in fecal samples of nondiarrheic and diarrheic calves supplemented with SCB, whereas fecal microbiota was predominated by Collinsella in diarrheic calves from the CON group. Live yeast supplementation in milk replacer led to a decrease of diarrhea in milk-fed veal calves and the fecal microbiota of diarrheic calves maintained a healthy community similar to nondiarrheic animals, with Fecalibacterium being the predominant genus.


Asunto(s)
Bacterias/clasificación , Enfermedades de los Bovinos/microbiología , Diarrea/veterinaria , Suplementos Dietéticos/análisis , Microbiota , Saccharomyces cerevisiae/fisiología , Alimentación Animal/análisis , Animales , Antibacterianos/uso terapéutico , Bacterias/genética , Peso Corporal/efectos de los fármacos , Bovinos , Enfermedades de los Bovinos/tratamiento farmacológico , Diarrea/tratamiento farmacológico , Diarrea/microbiología , Dieta/veterinaria , Ingestión de Alimentos , Heces/microbiología , Tracto Gastrointestinal/microbiología
3.
Occup Med (Lond) ; 66(8): 656-661, 2016 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-27497067

RESUMEN

BACKGROUND: Workplace-based assessment (WBA) is the assessment of specialist competence based on what a trainee doctor actually does in the workplace. Between January 2014 and January 2015, all UK occupational medicine (OM) trainees were invited to test a suite of direct observation of procedural skills (DOPS) tools designed in a supervised learning event (SLE) format. The Faculty of Occupational Medicine (FOM) Workplace-Based Assessment Advisory Group (WBAAG) studied feedback on the new format. AIMS: To assess the utility of the redesigned tools, including their acceptability, feasibility, usability and key aspects of their reliability and validity. METHODS: The face and content validity of the new forms were assessed by a comprehension trial (CT), inter-rater reliability by a video scoring exercise and usability and acceptability by an electronic survey of trainees and trainers. RESULTS: The CT of trainees and trainers indicated that the face and content validity of the revised tools were acceptable. Inter-rater reliability video assessments indicated there was consistency of grading among trainers. Sixty-eight per cent of trainees and 95% of trainers agreed that the redesigned tools were an improvement on the current WBA DOPS tools and 83% of trainees indicated the new tools encouraged them to reflect on their performance. CONCLUSIONS: The results from this pilot study provided evidence to support a request to the General Medical Council (GMC) for the new SLE-DOPS forms to be used for WBA in OM. These changes were accepted by the GMC in January 2016 for implementation in April 2016.

4.
Occup Med (Lond) ; 63(5): 348-53, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23749803

RESUMEN

BACKGROUND: Hen and quail eggs are commonly used in embryological research. While immunoglobin E (IgE)-associated allergy to hens' egg proteins is recognized in employees in the food industry, there are no previous reports from workers in embryological research. Two newly identified cases prompted us to examine the extent of this problem in a university laboratory. AIMS: To determine the prevalence and determinants of sensitization to egg among a group of workers in an embryological research laboratory. METHODS: Following the identification of egg sensitization in two research workers, we surveyed 116 employees from a single embryology research laboratory in 2005. Sensitization to egg was assessed by skin prick tests and/or specific IgE measurement and examined in relation to a number of potential determinants, including the extent of appropriate control measures. RESULTS: Four employees were sensitized to egg, each with digestive symptoms of egg allergy. All had worked directly with eggs, giving a prevalence of specific sensitization in that group of 6.1% (95% confidence interval (CI) [1.7%, 14.8%]). There was a statistically significant trend for those sensitized to report a shorter duration of exposure to eggs and less frequent use of hygiene control measures to reduce exposure. CONCLUSIONS: Sensitization to eggs among those occupationally exposed to egg protein in research work occurs more commonly than in the general population. The presence of digestive symptoms after eating eggs may be indicative of sensitization to egg and should be incorporated into health evaluation of exposed workers.


Asunto(s)
Investigación Biomédica , Pollos , Hipersensibilidad al Huevo/diagnóstico , Proteínas del Huevo/inmunología , Enfermedades del Esófago/diagnóstico , Mucosa Bucal/inmunología , Enfermedades Profesionales/diagnóstico , Codorniz , Adulto , Anciano , Animales , Embrión de Pollo , Estudios Transversales , Hipersensibilidad al Huevo/epidemiología , Hipersensibilidad al Huevo/inmunología , Embriología , Enfermedades del Esófago/epidemiología , Enfermedades del Esófago/inmunología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedades Profesionales/epidemiología , Enfermedades Profesionales/inmunología , Exposición Profesional , Prevalencia , Pruebas Cutáneas , Reino Unido/epidemiología
5.
Ecology ; 91(8): 2455-65, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20836467

RESUMEN

Issues of residual spatial autocorrelation (RSA) and spatial scale are critical to the study of species-environment relationships, because RSA invalidates many statistical procedures, while the scale of analysis affects the quantification of these relationships. Although these issues independently are widely covered in the literature, only sparse attention is given to their integration. This paper focuses on the interplay between RSA and the spatial scaling of species-environment relationships. Using a hypothetical species in an artificial landscape, we show that a mismatch between the scale of analysis and the scale of a species' response to its environment leads to a decrease in the portion of variation explained by environmental predictors. Moreover, it results in RSA and biased regression coefficients. This bias stems from error-predictor dependencies due to the scale mismatch, the magnitude of which depends on the interaction between the scale of landscape heterogeneity and the scale of a species' response to this heterogeneity. We show that explicitly considering scale effects on RSA can reveal the characteristic scale of a species' response to its environment. This is important, because the estimation of species-environment relationships using spatial regression methods proves to be erroneous in case of a scale mismatch, leading to spurious conclusions when scaling issues are not explicitly considered. The findings presented here highlight the importance of examining the appropriateness of the spatial scales used in analyses, since scale mismatches affect the rigor of statistical analyses and thereby the ability to understand the processes underlying spatial patterning in ecological phenomena.


Asunto(s)
Simulación por Computador , Ecosistema , Modelos Biológicos , Animales , Dinámica Poblacional , Lluvia , Árboles
6.
J Dairy Sci ; 93(8): 3713-21, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20655440

RESUMEN

Acquisition of high quality colostrum is an important factor influencing neonatal calf health. Many methods have been used to assess the Ig concentration of colostrum; however, improved, validated evaluation tools are needed. The aims of this study were to evaluate both optical and digital Brix refractometer instruments for the measurement of Ig concentration of colostrum as compared with the gold standard radial immunodiffusion assay laboratory assessment and to determine the correlation between Ig measurements taken from fresh and frozen colostrum samples for both Brix refractometer instruments. This research was completed using 288 colostrum samples from 3 different farms. It was concluded that the optical and digital Brix refractometers were highly correlated for both fresh and frozen samples (r=0.98 and r=0.97, respectively). Correlation between both refractometer instruments for fresh and frozen samples and the gold standard radial immunodiffusion assay were determined to be very similar, with a correlation coefficient between 0.71 and 0.74. Both instruments exhibited excellent test characteristics, indicating an appropriate cut-off point of 22% Brix score for the identification of good quality colostrum.


Asunto(s)
Bovinos/inmunología , Calostro/inmunología , Inmunoglobulina G/análisis , Refractometría/veterinaria , Animales , Criopreservación/veterinaria , Femenino , Inmunodifusión/métodos , Inmunodifusión/veterinaria , Embarazo , Refractometría/instrumentación , Refractometría/métodos , Reproducibilidad de los Resultados
7.
FEBS Lett ; 270(1-2): 67-70, 1990 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-2226792

RESUMEN

RNA was isolated from rat liver and heart tissues at various times up to 12 weeks after birth, and probed on slot blots with lactate dehydrogenase A and B cDNA probes. Although the relative abundances of LDH A in liver and LDH B in heart increased substantially in the 12 weeks after birth, mRNAs for both isoenzymes remained remarkably stable in both tissues over the same period. The implications of these observations for the regulation of constitutive gene expression are discussed.


Asunto(s)
L-Lactato Deshidrogenasa/metabolismo , Hígado/enzimología , Miocardio/enzimología , ARN Mensajero/metabolismo , Envejecimiento/metabolismo , Animales , Animales Recién Nacidos/genética , Northern Blotting , Sondas de ADN , Regulación Enzimológica de la Expresión Génica , L-Lactato Deshidrogenasa/genética , Sustancias Macromoleculares , Ratas , Ratas Endogámicas
8.
Surgery ; 93(1 Pt 2): 217-20, 1983 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-6336865

RESUMEN

A study of antibiotic treatment of intra-abdominal sepsis was conducted between May 1978 and May 1981. In the first phase, clindamycin (C) was compared with metronidazole (M), each combined with tobramycin (T), in a prospective, double-blind, randomized study. Twenty-three patients received C + T and 34 patients received M + T. The two groups were similar with respect to age, gender, underlying disease, presence of abscess, clinical condition, severity of illness, duration of illness before treatment and bacteriology. Anaerobic organisms outnumbered facultative and aerobic organisms. Bacteroides fragilis and Escherichia coli predominated. In the C + T group of patients, 74% had a good response. In the M + T group, 83% had good results. Adverse effects were few and minor in the two treatment groups. Three patients on C + T and one who received M + T followed by C + T died of infections; two patients died of underlying disease. In the second, open phase of the study, M + T was used to treat 45 patients with 46 courses. Twenty patients had intra-abdominal abscesses, which represented all grades of severity of illness. Five patients received long-term corticosteroid therapy. Almost half the patients had peritonitis complicating appendicitis. Good results were obtained in 81%. One patient died of the underlying disease and one died of infection complicating severe trauma and hypovolemic shock.


Asunto(s)
Abdomen , Infecciones Bacterianas/tratamiento farmacológico , Metronidazol/uso terapéutico , Abdomen/microbiología , Absceso/tratamiento farmacológico , Adulto , Anciano , Apendicitis/tratamiento farmacológico , Infecciones Bacterianas/microbiología , Clindamicina/uso terapéutico , Ensayos Clínicos como Asunto , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Peritonitis/tratamiento farmacológico , Estudios Prospectivos , Distribución Aleatoria , Tobramicina/uso terapéutico
9.
Clin J Pain ; 7(3): 192-204, 1991 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1809428

RESUMEN

Patients experience oral pain in ways that make an accurate diagnosis difficult. The same complaints can be caused by either dental or nonodontogenic diseases. The author systematically explores symptoms and etiologies to direct the health care provider to an accurate diagnosis and treatment.


Asunto(s)
Dolor/fisiopatología , Diente , Animales , Humanos , Dolor/etiología
10.
J Endod ; 15(9): 438-41, 1989 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2637338

RESUMEN

A lymphoma which was originally diagnosed as an inflammatory process is reported. A brief review of lymphoma's etiology, predilection for the oral cavity, and similarities to inflammation is presented. Particular emphasis is placed on the premise that an initial benign diagnosis may not be accurate and that monitoring patients is essential in any disease entity whether benign or malignant.


Asunto(s)
Linfoma/diagnóstico , Neoplasias de la Boca/diagnóstico , Humanos , Masculino , Persona de Mediana Edad
11.
J Endod ; 20(6): 288-91, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7931026

RESUMEN

An in vitro dye leakage study was performed to compare the apical microleakage of a glass ionomer root canal sealer to Roth's 801 sealer. Forty-five single-rooted teeth were randomly divided into three groups: Ketac-Endo, Roth's 801, and the control group (no sealer). All groups were instrumented using a step-back technique and obturated with laterally condensed gutta-percha. The teeth were placed in a vacuum chamber under a pressure of 710 torr for 15 min and then immersed in India ink under vacuum for 24 h. The teeth were allowed to passively stain for 4 days and were cleared and evaluated for linear dye leakage using a binocular dissecting microscope. Statistical analysis revealed that sealer significantly improves the apical seal of laterally condensed gutta-percha. However, the apical seal exhibited by Ketac-Endo was not significantly different from that provided by Roth's 801 sealer.


Asunto(s)
Filtración Dental/prevención & control , Cementos de Ionómero Vítreo , Materiales de Obturación del Conducto Radicular , Cemento de Óxido de Zinc-Eugenol , Análisis de Varianza , Humanos , Variaciones Dependientes del Observador , Distribución Aleatoria
12.
J Endod ; 19(6): 293-6, 1993 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8228749

RESUMEN

An in vitro dye leakage study was performed to determine the incidence of patent furcal accessory canals following exposure of the pulp chamber to 5.25% sodium hypochlorite. One hundred extracted molars were labeled, endodontically opened, and irrigated for 1 h at 5-min intervals. The external furcations were exposed to 0.5% basic fuchsin for 24 h. Patency was determined by dye presence on the chamber floor. Statistical analysis revealed that first and second molars, regardless of arch position or location, demonstrated a patent accessory canal at a rate of 57% +/- 19.6% in the furcal area. It was concluded that accessory canal exposure to 5.25% sodium hypochlorite in the furcal area of molars produced patency which was demonstrable via passive methods--no vacuum or injection pressures were utilized.


Asunto(s)
Cavidad Pulpar/anatomía & histología , Diente Molar/anatomía & histología , Distribución de Chi-Cuadrado , Colorantes , Filtración Dental/complicaciones , Filtración Dental/diagnóstico , Extravasación de Materiales Terapéuticos y Diagnósticos , Femenino , Defectos de Furcación/inducido químicamente , Humanos , Masculino , Hipoclorito de Sodio/efectos adversos , Raíz del Diente/anatomía & histología
13.
J Endod ; 16(5): 239-41, 1990 May.
Artículo en Inglés | MEDLINE | ID: mdl-2074420

RESUMEN

Biopsy reports of specimens from the apices of 1659 teeth physically present at the time the biopsy was performed were reviewed. The following information was recorded from each report: (a) source of specimen, (b) sex of patient, (c) age of patient, (d) location of tooth associated with lesion, and (e) diagnoses reported. Data were recorded and analyzed by chi-square analysis to note significant differences. This study found that 52% of the lesions were granulomas, 42% cysts, 2% periapical scars, and 4% other disorders. No differences were found between males and females in regard to age and location of lesions. Overall, the most common location for lesions was the maxillary anterior, followed by maxillary posterior, mandibular posterior, and finally the mandibular anterior jaw. This also was the case for all age ranges except 60 to 69 yr of age where lesions in the maxillary posterior area were most common. More granulomas were detected in all areas except in the mandibular posterior area where cysts were more common.


Asunto(s)
Enfermedades Periapicales/epidemiología , Adulto , Anciano , Biopsia , Distribución de Chi-Cuadrado , Femenino , Humanos , Masculino , Persona de Mediana Edad , Granuloma Periapical/epidemiología , Quiste Radicular/epidemiología , Estudios Retrospectivos
18.
Can Med Assoc J ; 125(11): 1217-21, 1981 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-6800624

RESUMEN

The records were reviewed of all patients treated at the Vancouver General Hospital over the 15 years from 1965 through 1979 for infections proved by culture to have been caused by Listeria monocytogenes. Although listeriosis is not common in humans, certain groups seem to be susceptible - immunocompromised patients, pregnant women, neonates and the elderly. All these groups were represented among the 22 cases reviewed. There were 17 adults, 3 of whom were pregnant women who had only a mild influenza-like illness. Of the remaining 14 adults 9 were immunocompromised and 5 apparently immunocompetent; 7 presented with meningitis and 7 with bacteremia only. Of the five infants with neonatal listeriosis, two had early-onset disease (bacteremia) and three had the late-onset form (meningitis). Seven patients were treated with penicillin alone, seven with ampicillin alone and eight with penicillin or ampicillin combined with kanamycin, gentamicin or chloramphenicol. There were eight deaths: several were directly attributable to the listeriosis, but in others the severity of the underlying illness was an important factor. Serotypes 1 and 4b were equally common among the 16 specimens of L. monocytogenes that were typed.


Asunto(s)
Listeriosis/epidemiología , Adulto , Anciano , Envejecimiento , Alcoholismo/complicaciones , Canadá , Endocarditis Bacteriana/complicaciones , Femenino , Hospitales Generales , Humanos , Recién Nacido , Fallo Renal Crónico/complicaciones , Listeria monocytogenes/aislamiento & purificación , Masculino , Pruebas de Sensibilidad Microbiana , Embarazo , Estudios Retrospectivos , Sepsis/microbiología
19.
Biochem J ; 263(1): 73-80, 1989 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-2481441

RESUMEN

Inclusion of aurintricarboxylic acid (ATA) in extraction buffers for the isolation of RNA from animal tissues resulted in high yields (0.5-2.0 mg/g of tissue) of undegraded material as judged by agarose-gel-electrophoretic analyses and Northern-blotting experiments. However, ATA bound to nucleic acids, forming stable complexes, and so we have established methods for spectrophotometric quantification of RNA in these coloured complexes, and for easy removal of sufficient ATA to leave RNA in a consistently hybridizable condition at the end of a purification. The use and subsequent removal of ATA was straightforward and gave satisfactory results for all rat tissues tested.


Asunto(s)
Ácido Aurintricarboxílico , Ácidos Ciclohexanocarboxílicos , ARN/aislamiento & purificación , Ribonucleasas/antagonistas & inhibidores , Animales , Ácido Aurintricarboxílico/análisis , Northern Blotting , Ácidos Ciclohexanocarboxílicos/análisis , ADN/metabolismo , Electroforesis en Gel de Agar , Indicadores y Reactivos , Hibridación de Ácido Nucleico , Ratas , Salmón , Espectrofotometría Ultravioleta
20.
Comp Biochem Physiol B ; 98(2-3): 279-82, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1873984

RESUMEN

1. We have quantified lactate dehydrogenase (LDH) A, B and C enzyme levels during the first twelve weeks of life in rat testes. 2. Proteins were electrophoresed under non-denaturing conditions, isoenzymes identified by activity staining and quantified by densitometry scanning. 3. LDH A declined 2-3-fold during testes growth, changing from the most to the least abundant isoenzyme form. LDH B remained fairly constant, and LDH C increased from undetectable levels at birth to become the most abundant of the three polypeptides from week 3 onwards.


Asunto(s)
L-Lactato Deshidrogenasa/metabolismo , Testículo/crecimiento & desarrollo , Envejecimiento/metabolismo , Animales , Isoenzimas , Sustancias Macromoleculares , Masculino , Ratas , Ratas Endogámicas , Testículo/enzimología
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