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1.
Rehabilitación (Madr., Ed. impr.) ; 55(2): 111-117, abr. - jun. 2021. tab
Artigo em Espanhol | IBECS | ID: ibc-227757

RESUMO

Objetivo El propósito de esta investigación se basó en identificar los factores que se asocian al riesgo cardiovascular en docentes de una universidad privada de Colombia. Materiales y métodos Se realizó un estudio descriptivo-transversal con fase analítica. Se realizó un muestreo probabilístico por fijación proporcional con docentes de tiempo completo, con un número de participantes de 104 docentes que cumplieron los criterios de inclusión. Resultados Con la participación de 55 mujeres (52,9%) y de 49 hombres (47,1%), se encontró relación estadísticamente significativa con la variable edad (p=0,001) con un OR 0,351; y con el índice de masa corporal (p=0,000) con un OR 6,071 estableciendo que existe seis veces la probabilidad de padecer una enfermedad cardiovascular por alteración del índice de masa corporal. Conclusión El índice de masa corporal es una variable constante en cuanto a la relación con la aparición de enfermedades cardiovasculares, lo cual refleja el estilo de vida de los individuos (AU)


Objective The aim of this study was to identify the factors associated with cardiovascular risk in teachers in a private university in Colombia. Materials and methods We performed a descriptive cross-sectional study with an analytical phase. Probabilistic sampling was performed by proportional fixation with 104 full-time teachers who met the inclusion criteria. Results There were 55 women (52.9%) and 49 men (47.1%). A statistically significant relationship was found with age (p=.001) with an OR 0.351, and with body mass index (p=.000) with an OR 6.071, establishing that altered body mass index conferred a 6-fold increased risk of cardiovascular disease. Conclusion Body mass index is a constant variable in terms of the relationship with the occurrence of cardiovascular disease, which reflects individuals’ lifestyle (AU)


Assuntos
Humanos , Masculino , Feminino , Doenças Cardiovasculares/epidemiologia , Docentes/estatística & dados numéricos , Estudos Transversais , Fatores de Risco , Universidades , Sobrepeso
2.
Rehabilitacion (Madr) ; 55(2): 111-117, 2021.
Artigo em Espanhol | MEDLINE | ID: mdl-33092850

RESUMO

OBJECTIVE: The aim of this study was to identify the factors associated with cardiovascular risk in teachers in a private university in Colombia. MATERIALS AND METHODS: We performed a descriptive cross-sectional study with an analytical phase. Probabilistic sampling was performed by proportional fixation with 104 full-time teachers who met the inclusion criteria. RESULTS: There were 55 women (52.9%) and 49 men (47.1%). A statistically significant relationship was found with age (p=.001) with an OR 0.351, and with body mass index (p=.000) with an OR 6.071, establishing that altered body mass index conferred a 6-fold increased risk of cardiovascular disease. CONCLUSION: Body mass index is a constant variable in terms of the relationship with the occurrence of cardiovascular disease, which reflects individuals' lifestyle.


Assuntos
Doenças Cardiovasculares , Doenças Cardiovasculares/epidemiologia , Estudos Transversais , Feminino , Fatores de Risco de Doenças Cardíacas , Humanos , Masculino , Sobrepeso , Fatores de Risco , Universidades
3.
Int J Obes (Lond) ; 41(12): 1824-1830, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28757642

RESUMO

BACKGROUND: Prevalence rates of obesity and related diseases are quickly reaching epidemic proportions among Hispanic males in the United States. Hispanic males suffer from the highest prevalence of obesity-related diseases when compared to all other racial/ethnic groups. Despite evidence showing that weight loss can significantly reduce the risk of obesity-related health implications, literature informing best practices to engage Hispanic males in weight management programs is scarce. PURPOSE: The purpose of the current study was to engage Spanish-speaking, Mexican-origin males with overweight or obesity to examine their perspectives of diet-related behaviors related to weight management. METHODS: Demographic and acculturation data were collected using questionnaires. Fourteen semistructured interviews were completed with an all-Spanish-speaking cohort of men (age: 45.0±9.8 years; BMI: 34.2±6.5 kg m-2) who were born outside of the United States. We conducted a thematic analysis using a hybrid deductive-inductive analysis strategy using a previously developed codebook that was updated during iterative analysis of interview transcripts. RESULTS: Participants reported that healthful eating habits were hindered, among other factors, by lack of knowledge, sociocultural norms and conceptualizations of masculinity. Viable diet-related intervention approaches also surfaced, including building consciousness, promotion of traditional knowledge and the integration of the family in interventions. CONCLUSION: Findings suggest that Spanish-speaking, Mexican-origin men have interest in actively engaging in behavior changes that improve their dietary habits and engage in weight management. Our findings yield valuable insights that can be used to formulate tailored intervention strategies to improve obesity prevention and treatment programs for this vulnerable subgroup.


Assuntos
Comportamento Alimentar/etnologia , Comportamentos Relacionados com a Saúde/etnologia , Hispânico ou Latino/psicologia , Masculinidade , Obesidade/etnologia , Obesidade/prevenção & controle , Aculturação , Adulto , Conhecimentos, Atitudes e Prática em Saúde , Promoção da Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/psicologia , Pesquisa Qualitativa , Comportamento de Redução do Risco , Inquéritos e Questionários , Estados Unidos
4.
Int J Cosmet Sci ; 38(6): 634-645, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27139432

RESUMO

Regulatory decisions regarding microbiological safety of cosmetics and personal care products are primarily hazard-based, where the presence of a potential pathogen determines decision-making. This contrasts with the Food industry where it is a commonplace to use a risk-based approach for ensuring microbiological safety. A risk-based approach allows consideration of the degree of exposure to assess unacceptable health risks. As there can be a number of advantages in using a risk-based approach to safety, this study explores the Codex Alimentarius (Codex) four-step Microbiological Risk Assessment (MRA) framework frequently used in the Food industry and examines how it can be applied to the safety assessment of personal care products. The hazard identification and hazard characterization steps (one and two) of the Codex MRA framework consider the main microorganisms of concern. These are addressed by reviewing the current industry guidelines for objectionable organisms and analysing reports of contaminated products notified by government agencies over a recent 5-year period, together with examples of reported outbreaks. Data related to estimation of exposure (step three) are discussed, and examples of possible calculations and references are included. The fourth step, performed by the risk assessor (risk characterization), is specific to each assessment and brings together the information from the first three steps to assess the risk. Although there are very few documented uses of the MRA approach for personal care products, this study illustrates that it is a practicable and sound approach for producing products that are safe by design. It can be helpful in the context of designing products and processes going to market and with setting of microbiological specifications. Additionally, it can be applied reactively to facilitate decision-making when contaminated products are released on to the marketplace. Currently, the knowledge available may only allow a qualitative or semi-quantitative rather than fully quantitative risk assessment, but an added benefit is that the disciplined structuring of available knowledge enables clear identification of gaps to target resources and if appropriate, instigate data generation.


Assuntos
Cosméticos , Medição de Risco , Bactérias/isolamento & purificação , Cosméticos/efeitos adversos , Humanos
5.
Physiol Biochem Zool ; 88(3): 246-53, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25860824

RESUMO

The choice of adequate breeding habitat and its associated thermoregulatory conditions are thought to be important in the evolution of amphibian reproductive strategies. Among leptodactylid frogs, there is a terrestrial cline in the oviposition sites chosen to build foam nests for eggs. Although several functions have been attributed to foam nests, their role in temperature regulation for embryos is unclear. Here we tested the hypothesis that foam nests buffer embryos from variation in air temperature. We examined the degree of terrestrial nest sites in three species, finding a terrestrial cline of sites in terms of distance from water. We tested whether this nest-insulation effect varied among these species that differ in the degree of terrestrial nest sites and whether translocating nests impacted embryonic mortality. Our results demonstrate a negative effect of translocating aquatic nests to land, inferred from the highest hatching success in natural nests sites. All nests attenuated environmental thermal variation, but more terrestrial nests buffered embryos from a greater range of temperatures than did aquatic ones. Altogether, our data indicate that foam nests insulate embryos from daily temperature fluctuations among leptodactylid frogs with different degrees of terrestrial nests, which may well have contributed to the evolution of this reproductive strategy.


Assuntos
Anuros/fisiologia , Comportamento de Nidação , Animais , Anuros/embriologia , Ecossistema , Embrião não Mamífero , Oviposição , Especificidade da Espécie , Temperatura
6.
Int J Cosmet Sci ; 37(2): 165-74, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25482451

RESUMO

Bacillus cereus is ubiquitous in nature and thus occurs naturally in a wide range of raw materials and foodstuffs. B. cereus spores are resistant to desiccation and heat and able to survive dry storage and cooking. Vegetative cells produce several toxins which on ingestion in sufficient numbers can cause vomiting and/or diarrhoea depending on the toxins produced. Gastrointestinal disease is commonly associated with reheated or inadequately cooked foods. In addition to being a rare cause of several acute infections (e.g. pneumonia and septicaemia), B. cereus can also cause localized infection of post-surgical or trauma wounds and is a rare but significant pathogen of the eye where it may result in severe endophthalmitis often leading to loss of vision. Key risk factors in such cases are trauma to the eye and retained contaminated intraocular foreign bodies. In addition, rare cases of B. cereus-associated keratitis (inflammation of the cornea) have been linked to contact lens use. Bacillus cereus is therefore a microbial contaminant that could adversely affect product safety of cosmetic and facial toiletries and pose a threat to the user if other key risk factors are also present. The infective dose in the human eye is unknown, but as few as 100 cfu has been reported to initiate infection in a susceptible animal model. However, we are not aware of any reports in the literature of B. cereus infections in any body site linked with use of personal care products. Low levels of B. cereus spores may on occasion be present in near-eye cosmetics, and these products have been used by consumers for many years. In addition, exposure to B. cereus is more likely to occur through other routes (e.g. dustborne contamination) due to its ubiquity and resistance properties of spores. The organism has been recovered from the eyes of healthy individuals. Therefore, although there may be a perceived hazard, the risk of severe eye infections as a consequence of exposure through contaminated near-eye cosmetics is judged to be vanishingly small. It is unlikely that more stringent microbiological standards for near-eye cosmetics will have any impact on the risk of severe eye infections caused by B. cereus, as these are not linked to use of personal care products.


Assuntos
Bacillus cereus/isolamento & purificação , Cosméticos , Bacillus cereus/patogenicidade , Exposição Ambiental , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos
7.
J Appl Microbiol ; 115(5): 1117-26, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23910391

RESUMO

AIM: The extensive use of microbicides in a wide range of applications has been questioned with regard to their role in the development of bacterial resistance to antimicrobials. This study aims to measure the phenotypic and genotypic changes in Burkholderia lata strain 383 exposed to chlorhexidine gluconate (CHG) and benzalkonium chloride (BZC), two commonly used cationic microbicides. METHODS AND RESULTS: The susceptibility of B. lata strain 383 to CHG and BZC and a range of antibiotics was determined using standardized MIC, MBC and antibiotic susceptibility testing protocols before and after short-term exposure to a low microbicide concentration. Measurements were performed on four separate occasions over a 1-year period. Changes in gene expression were investigated using quantitative real-time PCR. Although the susceptibility profile to CHG and BZC was not altered, a change in antibiotic susceptibility profile was observed for ceftazidime, and for imipenem and ciprofloxacin in 2/4 repeats. An outer membrane protein and ABC transporter were found to be significantly upregulated following treatment with BZC and CHG, respectively. CONCLUSIONS: The comparison of MIC and MBC results following microbicide exposure with baseline data offered a prospective protocol to quantify any change in bacterial susceptibility profile. However, the use of a standardized antibiotic susceptibility protocol with B. lata strain 383 showed some inconsistencies in results between repeats. SIGNIFICANCE AND IMPACT OF THE STUDY: With ever-increasing interest in the impact of microbicides on emerging antimicrobial resistance in bacteria growing, this study demonstrated that comparing susceptibility profile obtained after exposure to microbicides with baseline susceptibility values could play a role in establishing the potential risk of microbicide resistance and cross-resistance development and also in the development of a protocol that allows the prediction of microbicide resistance.


Assuntos
Anti-Infecciosos/farmacologia , Compostos de Benzalcônio/farmacologia , Complexo Burkholderia cepacia/efeitos dos fármacos , Clorexidina/análogos & derivados , Transportadores de Cassetes de Ligação de ATP/metabolismo , Proteínas da Membrana Bacteriana Externa/metabolismo , Complexo Burkholderia cepacia/genética , Cátions/farmacologia , Ceftazidima/farmacologia , Clorexidina/farmacologia , Ciprofloxacina/farmacologia , Farmacorresistência Bacteriana , Regulação Bacteriana da Expressão Gênica , Imipenem/farmacologia , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase em Tempo Real
8.
Ecohealth ; 10(1): 72-6, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23529763

RESUMO

The pathogenic chytrid fungus, Batrachochytrium dendrobatidis (Bd), constitutes a significant threat to more than 790 amphibian species occurring in Colombia. To date there is no molecular or morphological description of strains infecting Colombian populations. Here we report the genetic and morphological characterization of the first Colombian isolate of Bd (strain EV001). Our goals were threefold: (1) to characterize the morphology of EV001 using light and scanning electron microscopy, (2) to genotype this strain by direct sequencing of 17 polymorphic nuclear markers developed previously, and (3) to compare our findings with published reports on strains from other areas of the globe. We found that EV001 is morphologically consistent with previously described strains. Multi-locus genotyping suggested that EV001 is grouped genetically with Panamanian strains and is most similar to strain JEL203 isolated from a captive individual. This finding fills an important gap in our knowledge of Neotropical strains of Bd and provides a baseline for further evolutionary and functional analyses.


Assuntos
Anfíbios/microbiologia , Biodiversidade , Quitridiomicetos/genética , Anfíbios/genética , Animais , Quitridiomicetos/isolamento & purificação , Quitridiomicetos/patogenicidade , Colômbia , Genótipo , Reação em Cadeia da Polimerase
9.
Rev Argent Microbiol ; 41(1): 4-10, 2009.
Artigo em Espanhol | MEDLINE | ID: mdl-19391518

RESUMO

Helicobacter pylori successfully colonizes the gastric niche. These bacteria produce a vacuolating cytotoxin known as VacA, which is codified by the vacA gene. This protein represents an important virulence factor. H. pylori strains have different vacA alleles, which show a variety of phenotypes that have been associated with gastrointestinal diseases. The aim of this study was to generate data about the prevalence of H. pylori and the vacA genotype in Tolima (Colombia) residents, and to evaluate if there exists a relationship between these data and the development of different gastrointestinal pathologies. Seventy three patients with different pathologies were included. The DNA extracted from biopsy specimens was analyzed and the presence of bacteria was determined by amplifying a fragment of the 16 rDNA gene. The vacA genotype was also determined by PCR. Fifty-two percent out of the 50 genotyped samples showed vacA s1m1 allele, 42% vacA s2m2, 4% s1m2, and 2% s1,s2,m1,m2. A higher sensitivity for the detection of H. pylori was evidenced by amplifying the vacA gene rather than the 16S rDNA gene. No association was found between the vacA genotype and the gastrointestinal diseases included in the study.


Assuntos
Proteínas de Bactérias/genética , Gastrite/microbiologia , Genes Bacterianos , Infecções por Helicobacter/microbiologia , Helicobacter pylori/genética , Estômago/microbiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Colômbia/epidemiologia , DNA Bacteriano/genética , DNA Ribossômico/genética , Feminino , Gastrite/epidemiologia , Gastrite/patologia , Genótipo , Infecções por Helicobacter/epidemiologia , Infecções por Helicobacter/patologia , Helicobacter pylori/patogenicidade , Humanos , Masculino , Pessoa de Meia-Idade , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Sensibilidade e Especificidade , Estômago/patologia , Virulência/genética , Adulto Jovem
10.
Rev. argent. microbiol ; 41(1): 4-10, ene.-mar. 2009. graf, tab
Artigo em Espanhol | LILACS | ID: lil-634609

RESUMO

Helicobacter pylori es una bacteria que coloniza la mucosa gástrica de los humanos. Este microorganismo produce una citotoxina vacuolizante conocida como VacA y codificada por el gen vacA, el que se considera un factor de virulencia importante. Las cepas de H. pylori con diferentes alelos de vacA exhiben una gran variedad de fenotipos, algunos de los cuales han sido asociados con enfermedades gastroduodenales. El presente estudio pretende aportar datos sobre la prevalencia de H. pylori y de los genotipos de vacA en pacientes residentes en Tolima (Colombia), así como determinar la relación entre estos datos y el desarrollo de diferentes patologías gastroduodenales. Se incluyeron en este análisis 73 pacientes con diferentes patologías gástricas. Con el ADN total extraído de cada biopsia, se determinó la presencia de la bacteria mediante la amplificación de un fragmento específico del gen 16S ADNr. También se realizó la genotipificación del gen vacA por PCR. De las 50 muestras genotipificadas, el 52% mostró el alelo vacA s1m1, el 42% el alelo vacA s2m2, el 4% el s1m2 y el 2% los alelos s1,s2,m1,m2. Se evidenció una mayor sensibilidad en la detección de H. pylori por medio del gen vacA que por el gen 16S ADNr. En la población evaluada no se encontró asociación entre el genotipo de vacA y la presencia de las distintas patologías incluidas en este estudio.


Helicobacter pylori successfully colonizes the gastric niche. These bacteria produce a vacuolating cytotoxin known as VacA, which is codified by the vacA gene. This protein represents an important virulence factor. H. pylori strains have different vacA alleles, which show a variety of phenotypes that have been associated with gastrointestinal diseases. The aim of this study was to generate data about the prevalence of H. pylori and the vacA genotype in Tolima (Colombia) residents, and to evaluate if there exists a relationship between these data and the development of different gastrointestinal pathologies. Seventy three patients with different pathologies were included. The DNA extracted from biopsy specimens was analyzed and the presence of bacteria was determined by amplifying a fragment of the 16 rDNA gene. The vacA genotype was also determined by PCR. Fifty-two percent out of the 50 genotyped samples showed vacA s1m1 allele, 42% vacA s2m2, 4% s1m2, and 2% s1,s2,m1,m2. A higher sensitivity for the detection of H. pylori was evidenced by amplifying the vacA gene rather than the 16S rDNA gene. No association was found between the vacA genotype and the gastrointestinal diseases included in the study.


Assuntos
Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Proteínas de Bactérias/genética , Genes Bacterianos , Gastrite/microbiologia , Infecções por Helicobacter/microbiologia , Helicobacter pylori/genética , Estômago/microbiologia , Biópsia , Colômbia/epidemiologia , DNA Bacteriano/genética , DNA Ribossômico/genética , Genótipo , Gastrite/epidemiologia , Gastrite/patologia , Infecções por Helicobacter/epidemiologia , Infecções por Helicobacter/patologia , Helicobacter pylori/patogenicidade , RNA Bacteriano/genética , /genética , Sensibilidade e Especificidade , Estômago/patologia , Virulência/genética
11.
Mol Ecol Resour ; 8(6): 1326-8, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21586035

RESUMO

Within the anuran amphibians, dendrobatoids (poison-arrow frogs) are renowned for their parental care, but the lack of highly variable DNA markers so far precluded precise and comprehensive measurements of their genetic mating system. Here we present 10 polymorphic microsatellites for Allobates femoralis, a widespread dendrobatoid from the Amazon basin. In 24 field-collected individuals, we found between seven and 15 alleles per locus, without deviations from Hardy-Weinberg equilibrium or linkage disequilibrium. The loci will be employed to quantify reproductive success in view of male territoriality and female mate choice, as well as to determine the fine-scale genetic structure of local populations.

12.
J Food Prot ; 69(1): 118-29, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16416909

RESUMO

The survival of spore-forming bacteria is linked to the safety and stability of refrigerated processed foods of extended durability (REPFEDs). A probabilistic modeling approach was used to assess the prevalence and concentration of Bacillus cereus spores surviving heat treatment for a semiliquid chilled food product. This product received heat treatment to inactivate nonproteolytic Clostridium botulinum during manufacture and was designed to be kept at refrigerator temperature postmanufacture. As key inputs for the modeling, the assessment took into consideration the following factors: (i) contamination frequency (prevalence) and level (concentration) of both psychrotrophic and mesophilic strains of B. cereus, (ii) heat resistance of both types (expressed as decimal reduction times at 90 degrees C), and (iii) intrapouch variability of thermal kinetics during heat processing (expressed as the time spent at 90 degrees C). These three inputs were established as statistical distributions using expert opinion, literature data, and specific modeling, respectively. They were analyzed in a probabilistic model in which the outputs, expressed as distributions as well, were the proportion of the contaminated pouches (the likely prevalence) and the number of spores in the contaminated pouches (the likely concentration). The prevalence after thermal processing was estimated to be 11 and 49% for psychrotrophic and mesophilic strains, respectively. In the positive pouches, the bacterial concentration (considering psychrotrophic and mesophilic strains combined) was estimated to be 30 CFU/g (95th percentile). Such a probabilistic approach seems promising to help in (i) optimizing heat processes, (ii) identifying which key factor(s) to control, and (iii) providing information for subsequent assessment of B. cereus resuscitation and growth.


Assuntos
Bacillus cereus/fisiologia , Microbiologia de Alimentos , Temperatura Alta , Modelos Biológicos , Esporos Bacterianos/crescimento & desenvolvimento , Contagem de Colônia Microbiana , Qualidade de Produtos para o Consumidor , Contaminação de Alimentos , Manipulação de Alimentos/métodos , Humanos , Cinética , Esporos Bacterianos/isolamento & purificação
13.
Int J Food Microbiol ; 101(2): 123-44, 2005 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-15862875

RESUMO

Numerous small meat processors in the United States have difficulties complying with the stabilization performance standards for preventing growth of Clostridium perfringens by 1 log10 cycle during cooling of ready-to-eat (RTE) products. These standards were established by the Food Safety and Inspection Service (FSIS) of the US Department of Agriculture in 1999. In recent years, several attempts have been made to develop predictive models for growth of C. perfringens within the range of cooling temperatures included in the FSIS standards. Those studies mainly focused on microbiological aspects, using hypothesized cooling rates. Conversely, studies dealing with heat transfer models to predict cooling rates in meat products do not address microbial growth. Integration of heat transfer relationships with C. perfringens growth relationships during cooling of meat products has been very limited. Therefore, a computer simulation scheme was developed to analyze heat transfer phenomena and temperature-dependent C. perfringens growth during cooling of cooked boneless cured ham. The temperature history of ham was predicted using a finite element heat diffusion model. Validation of heat transfer predictions used experimental data collected in commercial meat-processing facilities. For C. perfringens growth, a dynamic model was developed using Baranyi's nonautonomous differential equation. The bacterium's growth model was integrated into the computer program using predicted temperature histories as input values. For cooling cooked hams from 66.6 degrees C to 4.4 degrees C using forced air, the maximum deviation between predicted and experimental core temperature data was 2.54 degrees C. Predicted C. perfringens growth curves obtained from dynamic modeling showed good agreement with validated results for three different cooling scenarios. Mean absolute values of relative errors were below 6%, and deviations between predicted and experimental cell counts were within 0.37 log10 CFU/g. For a cooling process which was in exact compliance with the FSIS stabilization performance standards, a mean net growth of 1.37 log10 CFU/g was predicted. This study introduced the combination of engineering modeling and microbiological modeling as a useful quantitative tool for general food safety applications, such as risk assessment and hazard analysis and critical control points (HACCP) plans.


Assuntos
Clostridium perfringens/crescimento & desenvolvimento , Manipulação de Alimentos/métodos , Produtos da Carne/microbiologia , Modelos Biológicos , Temperatura , Animais , Simulação por Computador , Qualidade de Produtos para o Consumidor , Análise de Elementos Finitos , Microbiologia de Alimentos , Temperatura Alta , Matemática , Valor Preditivo dos Testes , Medição de Risco , Células-Tronco , Suínos
14.
Artigo em Inglês | MEDLINE | ID: mdl-15278399

RESUMO

Territorial males of the pan-Amazonian Dart-poison frog, Epipedobates femoralis, are known to present stereotypic phonotactic responses to the playback of conspecific and synthetic calls. Fixed site attachment and a long calling period within an environment of little temperature change render this terrestrial and diurnal pan-Amazonian frog a rewarding species for field bioacoustics. In experiments at the field station Aratai, French Guiana, we tested whether the prominent frequency modulation of the advertisement-call notes is critical for eliciting phonotactic responses. Substitution of the natural upward sweep by either a pure tone within the species frequency range or a reverse sweep did not alter the males' phonotactic behavior. Playbacks with artificial advertisement calls embedded in high levels of either low-pass or high-pass masking noise designed to saturate nerve fibers from either the amphibian papilla or basilar papilla showed that male phonotactic behavior in this species is subserved by activation of the basilar papilla of the inner ear.


Assuntos
Comunicação Animal , Orelha Interna/fisiologia , Neurônios Aferentes/fisiologia , Ranidae/fisiologia , Vocalização Animal/fisiologia , Estimulação Acústica , Animais , Orelha Interna/inervação , Masculino , Comportamento Estereotipado
15.
J Food Prot ; 65(2): 316-25, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11848562

RESUMO

Forty-nine strains of lactic acid bacteria (LAB), isolated from commercially available ready-to-eat (RTE) meat products, were screened for their ability to inhibit the growth of Listeria monocytogenes at refrigeration (5 degrees C) temperatures on agar spot tests. The three most inhibitory strains were identified as Pediococcus acidilactici, Lactobacillus casei, and Lactobacillus paracasei by 16S rDNA sequence analysis. Their antilisterial activity was quantified in associative cultures in deMan Rogosa Sharpe (MRS) broth at 5 degrees C for 28 days, resulting in a pathogen reduction of 3.5 log10 cycles compared to its initial level. A combined culture of these strains was added to frankfurters and cooked ham coinoculated with L. monocytogenes, vacuum packaged, and stored at 5 degrees C for 28 days. Bacteriostatic activity was observed in cooked ham, whereas bactericidal activity was observed in frankfurters. Numbers of L. monocytogenes were 4.2 to 4.7 log10 and 2.6 log10 cycles lower than controls in frankfurters and cooked ham, respectively, after the 28-day refrigerated storage. In all cases, numbers of LAB increased by only 1 log10 cycle. The strain identified as P. acidilactici was possibly a bacteriocin producer, whereas the antilisterial activity of the other two strains was due to the production of organic acids. There was no significant difference (P > 0.05) in the antilisterial activity detected in frankfurters whether the LAB strains were used individually or as combined cultures. Further studies over a 56-day period indicated no impact on the quality of the product. This method represents a potential antilisterial intervention in RTE meats, because it inhibited the growth of the pathogen at refrigeration temperatures without causing sensory changes.


Assuntos
Lactobacillus/fisiologia , Listeria monocytogenes/crescimento & desenvolvimento , Produtos da Carne/microbiologia , Animais , Contagem de Colônia Microbiana , Conservação de Alimentos/métodos , Paladar , Temperatura , Fatores de Tempo
16.
J Food Prot ; 64(10): 1466-71, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11601691

RESUMO

Escherichia coli O157:H7, Salmonella spp., and Salmonella Typhimurium DT104 were stressed with lactic acid and cell-free supernatants from lactic acid bacteria and plated on three different media to determine if injured cells were recovered. A comparison of the susceptibility and recovery of antibiotic-resistant strains of the pathogens and nonresistant strains was also made. Acid stress conditions were created by adjusting the pH of a cocktail mixture (two to four strains) of the pathogen to 3.50 with lactic acid and holding for 18 h. The pathogen cocktail was also stressed with a cell-free supernatant of Lactobacillus lactis (pH 3.90) in a 4:6 ratio. Both nonstressed and stressed cocktail cultures were plated on Trypticase soy agar (TSA) and violet red bile agar (VRBA) for E. coli and xylose lysine tergitol4 (XLT4) for Salmonella. Repair of injured cells was evaluated by pour plating the stressed cells on a 5-ml thin layer of TSA and allowing a 2-h room temperature incubation followed by overlaying with VRBA or XLT4. There were significant reductions in the populations of both pathogens under both stress conditions when plating was done on nonselective media. Injured E. coli O157:H7 was not recovered on recovery or selective media compared with TSA. Numbers of cells of supernatant-stressed Salmonella spp. plated on selective and recovery media were similar to those on TSA. Acid-stressed cells for all Salmonella spp. were not recovered on TSA, selective, or recovery media at levels comparable to recovery on TSA. Antibiotic-resistant strains showed similar recovery patterns on all media evaluated. However, the antibiotic-resistant strains were less sensitive to both stress conditions. The use of antibiotic-resistant strains resulted in a greater recovery of stressed pathogens than the use of recovery media.


Assuntos
Escherichia coli O157/isolamento & purificação , Ácido Láctico/farmacologia , Salmonella/isolamento & purificação , Contagem de Colônia Microbiana , Meios de Cultura , Resistência Microbiana a Medicamentos , Escherichia coli O157/crescimento & desenvolvimento , Escherichia coli O157/patogenicidade , Concentração de Íons de Hidrogênio , Testes de Sensibilidade Microbiana , Salmonella/crescimento & desenvolvimento , Salmonella/patogenicidade , Fatores de Tempo
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