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AIM: The aim of this study was to describe factors affecting nursing education and labour markets in countries in East, Central, and Southern Africa, and critical areas for investment. BACKGROUND: An understanding about the relationship between the supply of nurses (determined by types of educational programmes, and the quantity and quality of nurse graduates), and workforce demand is critical to health policy development. METHODS: Six focus groups and 14 key informant interviews with nursing leaders and experts were conducted. Participants included government chief nursing officers, registrars of regulatory bodies, association leaders and heads of nursing education. The data were transcribed, coded and analysed using inductive techniques. FINDINGS: Participants discussed challenges and strengths of nursing education, school and regulatory infrastructure, financing mechanisms for the nursing workforce, the state of nursing jobs and scope of nursing practice. CONCLUSION: Strengthened regulations and leadership are needed to improve investment in nursing, the quality of nursing education, and working conditions and to promote the achievement of better health outcomes. IMPLICATIONS FOR NURSING POLICY: Clarifying scope of practice for nurses in the health sector and creating competency-based requirements is important. Governments should establish positions that align with updated competencies and provide fair and safe working conditions. The current and ongoing investment case for nursing requires improved data systems and a commitment to use labour market data for decision-making.
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Educación en Enfermería , Enfermeras Administradoras , Personal de Enfermería , Humanos , Liderazgo , Recursos HumanosRESUMEN
To support sperm production, fish testes undergo intense tissue remodelling, with endocrine, paracrine and autocrine signals regulating gonad physiology. The aim of this study was to investigate the testicular expression of insulin-like growth factor (Igf) 1 and Igf2 during spermatogenesis, and their relationship with cell proliferation and apoptosis throughout the reproductive cycle. The study was performed in male Hypostomus garmani, a catfish living in headwater rivers of the São Francisco River basin, Brazil. Spermatogenesis was analysed using histology, morphometry, immunohistochemistry and terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick end-labelling (TUNEL) analysis at different maturity stages. The results showed the proliferation of spermatogonia throughout the reproductive cycle, with a higher rate during the ripe stage. Germ and Sertoli cells expressed Igf1 at all stages of testicular maturity, Igf2 was predominant at the ripe stage and both Igf1 and Igf2 occurred at the spent stage. Caspase-3 and TUNEL analysis revealed a higher rate of apoptosis at the spent stage associated with reduced expression of Igf1 and Igf2. Sertoli cell proliferation was associated with spermatogonia and spermatocyte cysts at different stages of the reproductive cycle. Together, the data support a proliferative role for Igf1 and Igf2 in regulating testicular apoptosis in H. garmani, with cyclical variation in their expression during gonad maturation.
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Apoptosis/fisiología , Bagres/metabolismo , Proliferación Celular/fisiología , Factor II del Crecimiento Similar a la Insulina/metabolismo , Factor I del Crecimiento Similar a la Insulina/metabolismo , Espermatogénesis/fisiología , Espermatogonias/citología , Animales , Bagres/genética , Factor I del Crecimiento Similar a la Insulina/genética , Factor II del Crecimiento Similar a la Insulina/genética , Masculino , Células de Sertoli/metabolismo , Espermatogonias/metabolismo , Testículo/metabolismoRESUMEN
The COVID-19 pandemic has disrupted clinical nursing and midwifery education. This disruption has long-term implications for the nursing and midwifery workforce and for future healthcare responses to pandemics. Solutions may include enhanced partnerships between schools of nursing and midwifery and health service providers and including schools of nursing and midwifery in preparedness planning. These suggestions notwithstanding, we call upon national and international nursing and midwifery bodies to study how to further the clinical education of nurses and midwives during pandemics and other times of crisis.
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Betacoronavirus , Infecciones por Coronavirus/epidemiología , Bachillerato en Enfermería/normas , Partería/educación , Neumonía Viral/epidemiología , Facultades de Enfermería/organización & administración , COVID-19 , Curriculum/normas , Educación en Enfermería/normas , Femenino , Maternidades/organización & administración , Humanos , Servicios de Salud Materna/organización & administración , Partería/organización & administración , Pandemias , SARS-CoV-2RESUMEN
BACKGROUND/OBJECTIVES: Despite the effectiveness of bariatric surgery, there is still substantial variability in long-term weight outcomes and few factors with predictive power to explain this variability. Neuroimaging may provide a novel biomarker with utility beyond other commonly used variables in bariatric surgery trials to improve prediction of long-term weight-loss outcomes. The purpose of this study was to evaluate the effects of sleeve gastrectomy (SG) on reward and cognitive control circuitry postsurgery and determine the extent to which baseline brain activity predicts weight loss at 12-month postsurgery. SUBJECTS/METHODS: Using a longitudinal design, behavioral, hormone and neuroimaging data (during a desire for palatable food regulation paradigm) were collected from 18 patients undergoing SG at baseline (<1 month prior) and 12-month post-SG. RESULTS: SG patients lost an average of 29.0% of their weight (percentage of total weight loss (%TWL)) at 12-month post-SG, with significant variability (range: 16.0-43.5%). Maladaptive eating behaviors (uncontrolled, emotional and externally cued eating) improved (P<0.01), in parallel with reductions in fasting hormones (acyl ghrelin, leptin, glucose, insulin; P<0.05). Brain activity in the nucleus accumbens (NAcc), caudate, pallidum and amygdala during desire for palatable food enhancement vs regulation decreased from baseline to 12 months (P (family-wise error (FWE))<0.05). Dorsolateral and dorsomedial prefrontal cortex activity during desire for palatable food regulation (vs enhancement) increased from baseline to 12 months (P(FWE)<0.05). Baseline activity in the NAcc and hypothalamus during desire for palatable food enhancement was significantly predictive of %TWL at 12 months (P (FWE)<0.05), superior to behavioral and hormone predictors, which did not significantly predict %TWL (P>0.10). Using stepwise linear regression, left NAcc activity accounted for 54% of the explained variance in %TWL at 12 months. CONCLUSIONS: Consistent with previous obesity studies, reward-related neural circuit activity may serve as an objective, relatively robust predictor of postsurgery weight loss. Replication in larger studies is necessary to determine true effect sizes for outcome prediction.
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Cirugía Bariátrica/estadística & datos numéricos , Encéfalo/fisiología , Conducta Alimentaria/fisiología , Pérdida de Peso/fisiología , Adulto , Encéfalo/diagnóstico por imagen , Femenino , Humanos , Estudios Longitudinales , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Neuroimagen , Resultado del TratamientoRESUMEN
Purpose To better understand diagnostic delay and doctor-patient communication during the diagnosis of systemic lupus erythematous in patients without malar rash, we conducted a qualitative study of primary care providers' perceptions. Methods We conducted in-depth interviews with a purposive sample of eight primary care physicians in Kaiser Permanente Northern California. Telephone interviews were recorded, transcribed, reviewed, and coded for domains and themes. Results We identified five domains related to diagnosis: initial assessment and tests, initial diagnosis and empiric treatment, timeliness of diagnosis, communicating with the patient, and opportunities for improvement. In the absence of malar rash, the lupus manifestations are common while the disease is rare. Once the primary care provider believes that the disease may be autoimmune, they work with a rheumatologist, but this could take months. Initially, the physician assesses whether the condition is self-limiting or responds to empiric treatments. Over time, as empiric treatments fail or additional lupus manifestations emerge, the primary care provider makes a referral. Doctor-patient communication is critical to help the physician make sense of the symptoms, maintain trust, and assure the patient that he or she is receiving appropriate care. Patient persistence and communication are critically important. Continuing education was deemed essential by each physician. Conclusion In the absence of malar rash, a lupus diagnosis can be difficult. Enhanced doctor-patient communication, patient persistence, physician access to rheumatology and continuing education of primary care might improve time to diagnosis and the patient's experience with primary care. This knowledge is transferable to other rare, complex diseases.
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Lupus Eritematoso Sistémico/terapia , Atención Primaria de Salud , Investigación Cualitativa , Calidad de la Atención de Salud , Adulto , Comunicación , Educación Médica Continua , Femenino , Humanos , Lupus Eritematoso Sistémico/diagnóstico , Relaciones Médico-PacienteRESUMEN
Lecithin is a natural emulsifier used in a wide range of food and nonfood applications to improve physical stability, with no known bioactive effects. In this study, the effect of lecithin on the antimicrobial performance of a constant eugenol concentration was tested against three Escherichia coli strains (C600, 0.1229, and O157:H7 strain ATCC 700728). This is the first study, to our knowledge, focusing on lecithin at concentrations below those commonly used in foods to improve the stability of oil in water emulsions (≤10 mg/100 ml). For all three cultures, significant synergistic antimicrobial effects were observed when E. coli cultures were exposed to a constant eugenol concentration (ranging from 0.043 to 0.050% [wt/wt]) together with critical lecithin concentrations ranging from 0.5 to 1 mg/100 ml. Increasing the concentration of lecithin above 1 mg/100 ml (up to 10 mg/100 ml lecithin) diminished the antibacterial effect to values similar to those with eugenol-only treatments. The formation of aggregates (<100 nm) at the critical lecithin concentration was observed using cryo-transmission electron microscopy (cryo-TEM), together with a reduction in light absorbance at 284 nm. At critically low concentrations of lecithin, the formation of nanoscale aggregates is responsible for improving eugenol antimicrobial effects.IMPORTANCE Essential oils (EOs) are effective natural antimicrobials. However, their hydrophobicity and strong aromatic character limit the use of essential oils in food systems. Emulsifiers (e.g., lecithin) increase the stability of EOs in water-based systems but fail to consistently improve antimicrobial effects. We demonstrate that lecithin, within a narrow critical concentration window, can enhance the antimicrobial properties of eugenol. This study highlights the potential bioactivity of lecithin when utilized to effectively control foodborne pathogens.
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Antiinfecciosos/farmacología , Escherichia coli O157/efectos de los fármacos , Eugenol/farmacología , Microbiología de Alimentos , Lecitinas/análisis , Recuento de Colonia Microbiana , Emulsiones , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/farmacologíaRESUMEN
A light-induced Soret effect accompanied by photoinduced adsorption of pigment nanoparticles is described in organic solvents. We report an unexpected inversion of the nanoparticle flux which is directed along the temperarture gradient at short exposures to the light and switches against the gradient at longer exposures. This change of flux direction is due to light-induced adsorption of the nanocrystals onto the substrates of the cell.
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Alcanos/química , Luz , Nanopartículas/química , Solventes/química , Difusión Térmica , Adsorción , Colorantes , Estabilidad de Medicamentos , TemperaturaRESUMEN
Human noroviruses (HNoV) and hepatitis A virus (HAV) have been implicated in outbreaks linked to the consumption of presliced ready-to-eat deli meats. The objectives of this research were to determine the thermal inactivation kinetics of HNoV surrogates (murine norovirus 1 [MNV-1] and feline calicivirus strain F9 [FCV-F9]) and HAV in turkey deli meat, compare first-order and Weibull models to describe the data, and calculate Arrhenius activation energy values for each model. The D (decimal reduction time) values in the temperature range of 50 to 72°C calculated from the first-order model were 0.1 ± 0.0 to 9.9 ± 3.9 min for FCV-F9, 0.2 ± 0.0 to 21.0 ± 0.8 min for MNV-1, and 1.0 ± 0.1 to 42.0 ± 5.6 min for HAV. Using the Weibull model, the tD = 1 (time to destroy 1 log) values for FCV-F9, MNV-1, and HAV at the same temperatures ranged from 0.1 ± 0.0 to 11.9 ± 5.1 min, from 0.3 ± 0.1 to 17.8 ± 1.8 min, and from 0.6 ± 0.3 to 25.9 ± 3.7 min, respectively. The z (thermal resistance) values for FCV-F9, MNV-1, and HAV were 11.3 ± 2.1°C, 11.0 ± 1.6°C, and 13.4 ± 2.6°C, respectively, using the Weibull model. The z values using the first-order model were 11.9 ± 1.0°C, 10.9 ± 1.3°C, and 12.8 ± 1.7°C for FCV-F9, MNV-1, and HAV, respectively. For the Weibull model, estimated activation energies for FCV-F9, MNV-1, and HAV were 214 ± 28, 242 ± 36, and 154 ± 19 kJ/mole, respectively, while the calculated activation energies for the first-order model were 181 ± 16, 196 ± 5, and 167 ± 9 kJ/mole, respectively. Precise information on the thermal inactivation of HNoV surrogates and HAV in turkey deli meat was generated. This provided calculations of parameters for more-reliable thermal processes to inactivate viruses in contaminated presliced ready-to-eat deli meats and thus to reduce the risk of foodborne illness outbreaks.
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Enfermedades Transmitidas por los Alimentos/virología , Virus de la Hepatitis A/fisiología , Productos de la Carne/virología , Norovirus/fisiología , Inactivación de Virus , Animales , Contaminación de Alimentos/análisis , Virus de la Hepatitis A/química , Calor , Humanos , Cinética , Norovirus/química , Pavos/virologíaRESUMEN
AIMS: Epidemiological evidence suggests that hepatitis A virus (HAV) is the most common pathogen transmitted by bivalve molluscs such as clams, cockles, mussels and oysters. This study aimed to generate thermal inactivation kinetics for HAV as a first step to design adequate thermal processes to control clam-associated HAV outbreaks. METHODS AND RESULTS: Survivor curves and thermal death curves were generated for different treatment times (0-6 min) at different temperatures (50-72°C) and Weibull and first-order models were compared. D-values for HAV ranged from 47·37 ± 1·23 to 1·55 ± 0·12 min for the first-order model and 64·43 ± 3·47 to 1·25 ± 0·45 min for the Weibull model at temperatures from 50 to 72°C. z-Values for HAV in clams were 12·97 ± 0·59°C and 14·83 ± 0·0·28°C using the Weibull and first-order model respectively. The calculated activation energies for the first-order and Weibull model were 145 and 170 kJ mole(-1) respectively. CONCLUSION: The Weibull model described the thermal inactivation behaviour of HAV better than the first-order model. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides novel and precise information on thermal inactivation kinetics of HAV in homogenized clams. This will enable reliable thermal process calculations for HAV inactivation in clams and closely related seafood.
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Virus de la Hepatitis A/química , Virus de la Hepatitis A/crecimiento & desarrollo , Productos de la Carne/microbiología , Mercenaria/virología , Mariscos/virología , Animales , Calor , Cinética , Temperatura , Inactivación de VirusRESUMEN
Essential oil components (EOCs) have limited water solubility and are used at much higher concentrations in complex food matrices than in growth media to inhibit pathogens. However, the correlation between solubility and activity has not been studied. The objective of this work was to characterize the solubility of EOCs in solvents and milk and correlate solubility with antilisterial activity. The solubilities of four EOCs, thymol, carvacrol, eugenol, and trans-cinnamaldehyde, in water was significantly increased in the presence of 5% (vol/vol) ethanol. In milk, the solubility of EOCs was lower than in water, with lower solubility in higher-fat milk. EOCs applied to milk as stock solutions (in 95% aqueous ethanol) enabled quicker dissolution and higher solubility in milk serum than other methods of mixing, such as end to end, and greater reductions of Listeria monocytogenes Scott A after 0 and 24 h. When the EOC concentration detected in milk serum was above the minimum bactericidal concentration, complete inhibition of L. monocytogenes in tryptic soy broth resulted. Therefore, the antilisterial properties in milk could be correlated with the solubility by comparison to the minimum inhibitory or bactericidal concentrations of EOCs. While the EOCs applied using ethanol generally had solubility and activity characteristics superior to those of other mixing methods, ethanol is not used to a great extent in nonfermented foods. Therefore, mixing methods without an organic solvent may be more readily adaptable to enhancing the distribution of EOCs in complex food systems.
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Antibacterianos/química , Antibacterianos/farmacología , Listeria monocytogenes/efectos de los fármacos , Leche/química , Aceites Volátiles/química , Aceites Volátiles/farmacología , Manejo de Especímenes/métodos , Animales , Pruebas de Sensibilidad Microbiana , Leche/microbiología , SolubilidadRESUMEN
Hepatitis A virus (HAV) is a food-borne enteric virus responsible for outbreaks of hepatitis associated with shellfish consumption. The objectives of this study were to determine the thermal inactivation behavior of HAV in blue mussels, to compare the first-order and Weibull models to describe the data, to calculate Arrhenius activation energy for each model, and to evaluate model efficiency by using selected statistical criteria. The times required to reduce the population by 1 log cycle (D-values) calculated from the first-order model (50 to 72°C) ranged from 1.07 to 54.17 min for HAV. Using the Weibull model, the times required to destroy 1 log unit (tD = 1) of HAV at the same temperatures were 1.57 to 37.91 min. At 72°C, the treatment times required to achieve a 6-log reduction were 7.49 min for the first-order model and 8.47 min for the Weibull model. The z-values (changes in temperature required for a 90% change in the log D-values) calculated for HAV were 15.88 ± 3.97°C (R(2), 0.94) with the Weibull model and 12.97 ± 0.59°C (R(2), 0.93) with the first-order model. The calculated activation energies for the first-order model and the Weibull model were 165 and 153 kJ/mol, respectively. The results revealed that the Weibull model was more appropriate for representing the thermal inactivation behavior of HAV in blue mussels. Correct understanding of the thermal inactivation behavior of HAV could allow precise determination of the thermal process conditions to prevent food-borne viral outbreaks associated with the consumption of contaminated mussels.
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Culinaria/métodos , Contaminación de Alimentos/análisis , Virus de la Hepatitis A/crecimiento & desarrollo , Mytilus edulis/virología , Mariscos/virología , Inactivación de Virus , Animales , Virus de la Hepatitis A/química , Virus de la Hepatitis A/fisiología , Calor , CinéticaRESUMEN
Human noroviruses and hepatitis A virus (HAV) are considered as epidemiologically significant causes of foodborne disease. Therefore, studies are needed to bridge existing data gaps and determine appropriate parameters for thermal inactivation of human noroviruses and HAV. The objectives of this research were to compare the thermal inactivation kinetics of human norovirus surrogates (murine norovirus (MNV-1), and feline calicivirus (FCV-F9)) and HAV in buffered medium (2-ml vials), compare first-order and Weibull models to describe the data, calculate Arrhenius activation energy for each model, and evaluate model efficiency using selected statistical criteria. The D-values calculated from the first-order model (50-72 °C) ranged from 0.21-19.75 min for FCV-F9, 0.25-36.28 min for MNV-1, and 0.88-56.22 min for HAV. Using the Weibull model, the tD = 1 (time to destroy 1 log) for FCV-F9, MNV-1 and HAV at the same temperatures ranged from 0.10-13.27, 0.09-26.78, and 1.03-39.91 min, respectively. The z-values for FCV-F9, MNV-1, and HAV were 9.66 °C, 9.16 °C, and 14.50 °C, respectively, using the Weibull model. For the first order model, z-values were 9.36 °C, 9.32 °C, and 12.49 °C for FCV-F9, MNV-1, and HAV, respectively. For the Weibull model, estimated activation energies for FCV-F9, MNV-1, and HAV were 225, 278, and 182 kJ/mol, respectively, while the calculated activation energies for the first order model were 195, 202, and 171 kJ/mol, respectively. Knowledge of the thermal inactivation kinetics of norovirus surrogates and HAV will allow the development of processes that produce safer food products and improve consumer safety.
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Calicivirus Felino/crecimiento & desarrollo , Medios de Cultivo/química , Virus de la Hepatitis A/crecimiento & desarrollo , Norovirus/crecimiento & desarrollo , Esterilización/métodos , Inactivación de Virus , Animales , Calicivirus Felino/química , Virus de la Hepatitis A/química , Humanos , Cinética , Norovirus/química , Norovirus/clasificación , Esterilización/instrumentación , TemperaturaRESUMEN
Block copolymers form nanostructures that have interesting physical properties because they combine, for a single compound, the complementary features brought by each block. However, in order to fully exploit these properties, the physical state of each kind of domain must be precisely controlled. In this work, triblock PS-b-PEO-b-PS copolymers consisting of a central poly(ethylene oxide) (PEO) block covalently bonded to polystyrene (PS) blocks were synthesized by Atom Transfer Radical Polymerization. Their morphology was investigated by X-ray scattering and TEM experiments whereas their thermodynamic behavior was characterized by DSC. A strong decrease of both the melting temperature and the degree of crystallinity of PEO, due to its confinement between the PS domains, was observed and analyzed with a modified Gibbs-Thomson equation, following the approaches used for fluids confined in porous media. The existence of an amorphous bound layer, a few nanometers thick, at the PEO/PS interface, that does not undergo any phase transition in the temperature range investigated, accounts for both the melting temperature depression and the decrease of crystallinity upon confinement. This interfacial layer may significantly affect the mechanical and transport properties of these block copolymers that find applications as solid polymer electrolytes in batteries for example. Moreover, the value obtained for the solid PEO/liquid PEO surface tension is lower than those previously published but is thermodynamically consistent with the surface tensions of polymers at the solid/vapor and liquid/vapor interfaces.
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PURPOSE: Previous systematic reviews have found patient education to be moderately efficacious in decreasing the intensity of cancer pain, but variation in results warrants analysis aimed at identifying which strategies are optimal. METHODS: A systematic review and meta-analysis was undertaken using a theory-based approach to classifying and comparing educational interventions for cancer pain. The reference lists of previous reviews and MEDLINE, PsycINFO, and CENTRAL were searched in May 2012. Studies had to be published in a peer-reviewed English language journal and compare the effect on cancer pain intensity of education with usual care. Meta-analyses used standardized effect sizes (ES) and a random effects model. Subgroup analyses compared intervention components categorized using the Michie et al. (Implement Sci 6:42, 2011) capability, opportunity, and motivation behavior (COM-B) model. RESULTS: Fifteen randomized controlled trials met the criteria. As expected, meta-analysis identified a small-moderate ES favoring education versus usual care (ES, 0.27 [-0.47, -0.07]; P = 0.007) with substantial heterogeneity (I² = 71 %). Subgroup analyses based on the taxonomy found that interventions using "enablement" were efficacious (ES, 0.35 [-0.63, -0.08]; P = 0.01), whereas those lacking this component were not (ES, 0.18 [-0.46, 0.10]; P = 0.20). However, the subgroup effect was nonsignificant (P = 0.39), and heterogeneity was not reduced. Factoring in the variable of individualized versus non-individualized influenced neither efficacy nor heterogeneity. CONCLUSIONS: The current meta-analysis follows a trend in using theory to understand the mechanisms of complex interventions. We suggest that future efforts focus on interventions that target patient self-efficacy. Authors are encouraged to report comprehensive details of interventions and methods to inform synthesis, replication, and refinement.
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Neoplasias/complicaciones , Neoplasias/terapia , Manejo del Dolor/métodos , Manejo del Dolor/normas , Dolor/etiología , Educación del Paciente como Asunto/métodos , Educación del Paciente como Asunto/normas , HumanosRESUMEN
The Brazilian merganser (Mergus octosetaceus) is one of the most endangered bird species in South America and comprises less than 250 mature individuals in wild environments. This is a species extremely sensitive to environmental disturbances and restricted to a few "pristine" freshwater habitats in Brazil, and it has been classified as Critically Endangered on the IUCN Red List since 1994. Thus, biological conservation studies are vital to promote adequate management strategies and to avoid the decline of merganser populations. In this context, to understand the evolutionary dynamics and the current genetic diversity of remaining Brazilian merganser populations, we used the "Genotyping by Sequencing" approach to genotype 923 SNPs in 30 individuals from all known areas of occurrence. These populations revealed a low genetic diversity and high inbreeding levels, likely due to the recent population decline associated with habitat loss. Furthermore, it showed a moderate level of genetic differentiation between all populations located in four separated areas of the highly threatened Cerrado biome. The results indicate that urgent actions for the conservation of the species should be accompanied by careful genetic monitoring to allow appropriate in situ and ex situ management to increase the long-term species' survival in its natural environment.
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Essential oils are marginally soluble in water, making it challenging to evenly disperse them in foods and resulting in an increased tendency to bind with food lipids and proteins, resulting in lowered antimicrobial efficacy. In the current study, free and nano-dispersed (ND) thymol were compared in terms of their antimicrobial efficacies against Escherichia coli O157:H7 ATCC 43889 and 43894 and Listeria monocytogenes strains Scott A and 101 in apple cider and 2% reduced-fat milk. Apple cider was adjusted to pHs 5.5 and 3.5, and antimicrobial tests were performed at 0.3-, 0.5-, 0.75-, and 1.0-g/liter thymol concentrations at 35, 32, 25, and 4°C. Overall, 0.5 and 1.0 g/liter thymol in nano-dispersion and along with free thymol were inhibitory and bactericidal, respectively, against bacterial strains under all treatment conditions. At pH 5.5, 0.5 g/liter ND thymol was bacteriostatic against L. monocytogenes and E. coli for up to 48 h. At pH 3.5, L. monocytogenes controls did not survive beyond 12 h but E. coli survived and was inhibited by 0.5 g/liter ND thymol after 12 and 48 h in apple cider. E. coli strains were significantly sensitive to 4°C and pH 3.5 (P < 0.05). When bacteria were tested in 2% reduced-fat milk at 35 or 32°C, ND and free thymol demonstrated inhibition at 4.5 g/liter. Thus, the current technology seems to be promising and novel, enabling thymol-containing nano-dispersions that are not only transparent but also effective against pathogens in food applications, especially in clear beverages.
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Antibacterianos/química , Antibacterianos/farmacocinética , Escherichia coli O157/efectos de los fármacos , Listeria monocytogenes/efectos de los fármacos , Nanoestructuras , Timol/química , Timol/farmacocinética , Animales , Bebidas/microbiología , Concentración de Iones de Hidrógeno , Viabilidad Microbiana/efectos de los fármacos , Leche/microbiología , Temperatura , Factores de TiempoRESUMEN
Even though muscle injuries are very common, few scientific data on their effective treatment exist. Growth Factors (GFs) may have a role in accelerating muscle repair processes and a currently available strategy for their delivery into the lesion site is the use of autologous platelet-rich plasma (PRP). The present study is focused on the use of Platelet Rich Fibrin Matrix (PRFM), as a source of GFs. Bilateral muscular lesions were created on the longissimus dorsi muscle of Wistar rats. One side of the lesion was filled with a PRFM while the contralateral was left untreated (controls). Animals were sacrificed at 5, 10, 40 and 60 days from surgery. Histological, immunohistochemical and histomorphometric analyses were performed to evaluate muscle regeneration, neovascularization, fibrosis and inflammation. The presence of metaplasia zones, calcifications and heterotopic ossification were also assessed. PRFM treated muscles exhibited an improved muscular regeneration, an increase in neovascularization, and a slight reduction of fibrosis compared with controls. No differences were detected for inflammation. Metaplasia, ossification and heterotopic calcification were not detected. This preliminary morphological experimental study shows that PRFM use can improve muscle regeneration and long-term vascularization. Since autologous blood products are safe, PRFM may be a useful and handy product in clinical treatment of muscle injuries.
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Fibrina/farmacología , Músculo Esquelético/lesiones , Neovascularización Fisiológica/efectos de los fármacos , Plasma Rico en Plaquetas , Regeneración/efectos de los fármacos , Animales , Masculino , Músculo Esquelético/patología , Ratas , Ratas WistarRESUMEN
Chitosan is known to have bactericidal and antifungal activity. Although human noroviruses are the leading cause of non-bacterial gastroenteritis, information on the efficacy of chitosan against foodborne viruses is very limited. The objective of this work was to determine the effectiveness of different molecular weight chitosans against the cultivable human norovirus and enteric virus surrogates, feline calicivirus, FCV-F9, murine norovirus, MNV-1, and bacteriophages, MS2 and phiX174. Five purified chitosans (53, 222, 307, 421, ~1150 kDa) were dissolved in water, 1% acetic acid, or aqueous HCl pH = 4.3, sterilized by membrane filtration, and mixed with equal volume of virus to obtain a final concentration of 0.7% chitosan and 5 log(10) PFU/ml virus. Virus-chitosan suspensions were incubated for 3 h at 37 °C. Untreated viruses in PBS, in PBS with acetic acid, and in PBS with HCl were tested as controls. Each experiment was run in duplicate and replicated at least twice. Water-soluble chitosan (53 kDa) reduced phiX174, MS2, FCV-F9 and MNV-1 titers by 0.59, 2.44, 3.36, and 0.34 log(10) PFU/ml respectively. Chitosans in acetic acid decreased phiX174 by 1.19-1.29, MS2 by 1.88-5.37, FCV-F9 by 2.27-2.94, and MNV-1 by 0.09-0.28 log(10) PFU/ml, respectively. Increasing the MW of chitosan corresponded with an increasing antiviral effect on MS2, but did not appear to play a role for the other three tested viral surrogates. Overall, chitosan treatments showed the greatest reduction for FCV-F9, and MS2 followed by phiX174, and with no significant effect on MNV-1.
Asunto(s)
Infecciones por Caliciviridae/veterinaria , Infecciones por Caliciviridae/virología , Quitosano/farmacología , Norovirus/fisiología , Inactivación de Virus/efectos de los fármacos , Animales , Enfermedades de los Gatos/virología , Gatos , Línea Celular , Humanos , Norovirus/efectos de los fármacosRESUMEN
Human noroviruses (HNoV) have been implicated in gastrointestinal outbreaks associated with fresh produce, juices, and ready-to-eat foods. In order to determine the risk of HNoV transmission by contaminated blueberry juice, survival characteristics of cultivable HNoV surrogates (murine norovirus, MNV-1; feline calicivirus, FCV-F9; and bacteriophage MS2) in blueberry juice (pH = 2.77) after 0, 1, 2, 7, 14, and 21 days at refrigeration temperatures (4°C) were studied. High-pressure homogenization (HPH) was studied as a novel processing method for noroviral surrogate inactivation in blueberry juice. Blueberry juice or phosphate-buffered saline (PBS; pH 7.2 as control) was inoculated with each virus, stored over 21 days at 4°C or subjected to HPH, and plaque assayed. FCV-F9 (â¼5 log(10) PFU/mL) was undetectable after 1 day in blueberry juice at 4°C. MNV-1 (â¼4 log(10) PFU/ml) showed minimal reduction (1 log(10) PFU/mL) after 14 days, with greater reduction (1.95 log(10) PFU/mL; p < 0.05) after 21 days in blueberry juice at 4°C. Bacteriophage MS2 (â¼6 log(10) PFU/mL) showed significant reduction (1.93 log(10) PFU/mL; p < 0.05) after 2 days and was undetectable after 7 days in blueberry juice at 4°C. FCV-F9 remained viable in PBS for up to 21 days (2.28 log(10) PFU/mL reduction), while MNV-1 and MS2 survived after 21 days (1.08 and 0.56 log(10) PFU/mL reduction, respectively). Intriguingly, FCV-F9 and bacteriophage MS2 showed reduction after minimal homogenization pressures in blueberry juice (pH = 2.77), possibly due to the combination of juice pH, juice components, and mechanical effects. MNV-1 in blueberry juice was only slightly reduced at 250 (0.33 log(10) PFU/mL) and 300 MPa (0.71 log(10) PFU/mL). Virus surrogate survival in blueberry juice at 4°C correlates well with the ease of HNoV transmission via juices. HPH for viral inactivation in juices is dependent on virus type, and higher homogenization pressures may be needed for MNV-1 inactivation.
Asunto(s)
Bebidas/virología , Arándanos Azules (Planta)/virología , Contaminación de Alimentos/prevención & control , Manipulación de Alimentos/métodos , Conservación de Alimentos/métodos , Norovirus/crecimiento & desarrollo , Animales , Calicivirus Felino/crecimiento & desarrollo , Gatos , Línea Celular , Frío , Seguridad de Productos para el Consumidor , Microbiología de Alimentos , Humanos , Levivirus/crecimiento & desarrollo , Ratones , Presión , Ensayo de Placa Viral , Inactivación de VirusRESUMEN
PURPOSE: To examine differences in academic performance between male and female nursing students, and to identify whether professional identity and language usage were explanatory factors of academic performance. BACKGROUND: Although the numbers of men entering the nursing profession are increasing, societal stereotypes and the lack of male role models in nursing may have a negative impact on motivation, and hence, academic performance. METHODS: A total of 147 students who were enrolled in an undergraduate nursing programme in Peninsula Malaysia were surveyed in January 2011. In addition to demographic and academic data, three instruments were administered to measure language acculturation and professional identity. FINDINGS: The mean age of participants was 20.0 (SD: 1.5) years with 81% being female. Almost all students spoke the Malay language at home. Although there were no differences between male and female nursing students in relation to professional identity (P=0.496), male nursing students reported a lower mean English language usage score (9.9 vs. 10.9, P=0.011) and a higher mean Malay language usage score (20.4 vs. 18.8, P=0.017). Males were also found to have lower academic performance than female students, as measured by grade point average (GPA) (2.7 vs. 3.2, P<0.001). Regression analysis revealed gender was the only significant predictor of academic performance (ß=-0.44, P<0.001). CONCLUSIONS: Males represent less than 10% of the nursing workforce in developed countries, with some developing countries experiencing even lower participation rates. Promoting academic support of male nursing students may assist in increasing the number of male registered nurses in the nursing workforce.