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Silicon-based two-dimensional (2D) materials have garnered significant attention due to their unique properties and potential applications in electronics, optoelectronics, and other advanced technologies. Here, we present a comprehensive investigation of a novel silicon allotrope, Popsilicene (Pop-Si), derived from the structure of Popgraphene. Using density functional theory and ab initio molecular dynamics simulations, we explore the thermal stability, mechanical and electronic properties, and optical characteristics of Pop-Si. Our results demonstrate that Pop-Si exhibits good thermal stability at 1000 K. Electronic structure calculations reveal that Pop-Si is metallic, with a high density of states at the Fermi level. Furthermore, our analysis of the optical properties indicates that Pop-Si has pronounced UV-Vis optical activity, making it a promising candidate for optoelectronic devices. Mechanical property assessments show that Pop-Si has Young's modulus ranging from 10 to 92 GPa and a Poisson's ratio of 0.95. These results combined suggest its potential for practical applications.
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OBJECTIVES: A history of childbirth is associated with musculoskeletal injury (MSKi) in female members of the Canadian Armed Forces (CAF). While previous injury and pregnancy impact knee kinematics, it is unclear if a history of childbirth is associated with medial knee displacement (MKD) in an overhead squat movement screen. The aim of this study is to examine the relationship between MKD and (1) MSKi and (2) parity status in female CAF members. METHODS: 24 nulliparous and 21 parous female participants employed by the CAF completed a comprehensive physical fitness assessment of muscular flexibility, power, strength, endurance, aerobic capacity and a bodyweight overhead squat movement screen (recorded using two-dimensional video, and hip-knee-ankle angle measured using Kinovea software). Interactions between MKD, parity status and MSKi history were assessed by one-way analysis of variance and two-way analysis of covariance (ANCOVA) (adjusted for age). RESULTS: An interaction between parity status and acute injury of the lower extremity was observed (F=4.379, p=0.043, η2 =0.099) in MKD of the right knee. The two-way ANCOVA examining acute injury of the lumbopelvic hip complex (lower back, pelvis, hip) yielded an interaction between acute injury to the lumbopelvic hip complex and parity status (F=4.601, p=0.038, η2=0.103) in MKD asymmetry. DISCUSSION: Parous participants with acute injury to the lower extremity had larger MKD than parous without this injury type. Parous participants without acute injury to the lumbopelvic hip complex had greater MKD asymmetry than nulliparous without this injury type. Our findings suggest that researchers and clinicians should consider parity status in conjunction with MSKi history when assessing knee kinematics in female military members.
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We analyzed here the in silico biological activities of caffeine, (+)-catechin, and theobromine. For this, the PubChem database of the NIH (National Institutes of Health) was used to obtain the SMILE canonical form of the bioactive molecules, and the free software PASS Online (Prediction of Activity Spectra for Substances) from the Way2Drug portal. Also, we conducted an in vitro experiment using a chronic myeloid leukemia (CML) cell line (K562) to confirm some results found in in silico investigation. These cells were exposed to different concentrations of caffeine, (+)-catechin, and theobromine for 72 h. The results found in this in silico study suggested that caffeine, (+)-catechin, and theobromine showed excellent biological properties, such as antioxidant, anti-inflammatory, and anticarcinogenic, as well as protection against cardiovascular, diabetes, neurological, allergic, respiratory, and other therapeutic activities. These findings can be elucidated through the modulation exerted by these bioactive molecules in many biochemical pathways involved in organism homeostasis, such as free radical scavenger action, oxidoreductase inhibitor, membrane permeability inhibitor, and lipid peroxidase inhibitor. In addition, we have found here that caffeine, (+)-catechin, and theobromine have a remarkable anti-inflammatory activity which plays an important role in the therapeutic approach of COVID-19. Moreover, our in vitro findings confirmed the in silico results regarding anticancer activity since these molecules reduce cell proliferation at all tested concentrations. Therefore, since these molecules exhibit important medicinal activities, further investigations should be conducted to reveal new therapies to improve the treatments and prevention of numerous disorders and, consequently, promote human health.
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Renal neoplasms are highlighted as one of the 10 most common types of cancer. Renal cell carcinoma (RCC) is the most common type of renal cancer, considered the seventh most common type of cancer in the Western world. The most frequently altered genes described as altered are VHL, PBRM1, SETD2, KDM5C, PTEN, BAP1, mTOR, TP53, TCEB1 (ELOC), SMARCA4, ARID1A, and PIK3CA. RCC therapies can be classified in three groups: monoclonal antibodies, tyrosine kinase inhibitors, and mTOR inhibitors. Besides, there are targeted agents to treat RCC. However, frequently patients present side effects and resistance. Even though many multidrug resistance mechanisms already have been reported to RCC, studies focused on revealing new biomarkers as well as more effective antitumor therapies with no or low side effects are very important. Some studies reported that natural products, such as honey, epigallocatechin-3-gallate (EGCG), curcumin, resveratrol, and englerin A showed antitumor activity against RCC. Moreover, nanoscience is another strategy to improve RCC treatment and reduce the side effects due to the improvement in pharmacokinetics and reduction of toxicities of chemotherapies. Taking this into account, we conducted a systemic review of recent research findings on RCC hallmarks, drug resistance, and adjuvant therapies. In conclusion, a range of studies reported that RCC is characterized by high incidence and increased mortality rates because of the development of resistance to standard therapies. Given the importance of improving RCC treatment and reducing adverse effects, nanoscience and natural products can be included in therapeutic strategies.
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CONTEXT: Patients in palliative care are found in different places where care is provided, including the intensive care environment with important role of the nursing staff. OBJECTIVE: The aim of this systematic review was to answer the following question: which nursing interventions are aimed to the palliative care patients who are in the intensive care unit (ICU). DATA SOURCES: US National Library of Medicine (PUBMED), Virtual Health Library (BVS), SciELO, The Cochrane Library (Cochrane) and Lilacs databases were used. DATA EXTRACTION: After applying inclusion and exclusion criteria in accordance with the PRISMA method, a total of 36 entries published between 2010 and 2020 were used. DATA ANALYSIS: The records extracted were analyzed from a qualitative approach, so no statistical analysis was carried out. RESULTS: The findings demonstrated that the interventions that focus on promoting the patient's autonomy and respect their needs on ICU involves effective communication, promoting shared decision with patient and family, individualize care for each patient including the family on the daily care and decisions, maintaining basic nursing care as hygiene and comfort and encouraging self-care, as well as the involvement of nursing palliative care specialists the care is important. Other interventions included promoting a continuing education program for the nursing staff and other professionals involved in caring for patients in palliative care at ICU. CONCLUSION: This review highlighted the need for specific nursing interventions aimed at palliative care patients at ICU to promote patient autonomy and the focus on patient needs, always sharing decisions with the patient and family. However, it showed that there is a need for the continuous training of the nursing staff because factors such as the nurses' lack of technical-scientific knowledge and, concomitantly, the absence of a standardized and specific intervention model linked to a bureaucratic system, make it difficult to carry out a specialized care for this type of patient.
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Enfermagem de Cuidados Paliativos na Terminalidade da Vida , Recursos Humanos de Enfermagem , Estados Unidos , Humanos , Cuidados Paliativos , Unidades de Terapia Intensiva , Cuidados CríticosRESUMO
RESUMEN Los Niveles de Referencia para Diagnóstico (NRD) son una herramienta dinámica que gana cada vez una mayor importancia para la optimización de las exposiciones médicas. La disponibilidad de información científica es esencial en este proceso de optimización para Medicina Nuclear (MN) y Radiología Diagnóstica (RD). Este trabajo presenta un estudio de la disponibilidad de información sobre los NRD para MN y RD en la base PubMed, en los últimos 20 años, empleando diferentes palabras clave. Se analizó de forma crítica la información disponible, buscando los cambios principales que se han producido como tendencia en diferentes aspectos del establecimiento de los NRD. Se verificó un desbalance significativo en la disponibilidad de literatura científica en estas dos áreas, aunque se ha incrementado la información para equipos híbridos y de forma general para todas las tecnologías. Este desbalance se hace mayor para estudios de medicina nuclear en pediatría. Se observaron avances en la forma de recolectar datos, la manera de organizar la información y analizarla, en especial con la disponibilidad de sistemas de monitoreo de dosis. Se encontró que, en los estudios TC e intervencionismo, las agrupaciones por localización anatómica están siendo acotadas o restringidas, por indicaciones clínicas que tienen similitudes en los requisitos de calidad de imagen para el diagnóstico adecuado. Similarmente en MN se vislumbra la incorporación de la actividad por peso como NRD en las tecnologías híbridas y estudios pediátricos. Este estudio demuestra que, en general, la literatura científica disponible sobre los NRD es mucho más amplia para pacientes adultos. Se requiere más estudios pediátricos, especialmente en el área de MN
ABSTRACT Diagnostic Reference Levels (DRLs) are a dynamic tool that is gaining more and more importance for the optimization of medical exposures. The availability of scientific information is essential in this optimization process for Nuclear Medicine (NM) and Diagnostic Radiology (DR). This work presents a revision of the information's availability about DRL in the PubMed database, in the last 20 years, using different search combinations. The available information was critically analyzed, looking for the main changes that have occurred as a trend in different aspects of the establishment of the NRD. A significant disparity in the amount of information between the two areas on the subject was verified, although there has been an increase of available scientific papers for hybrid equipment, and in general for all technologies. The disparity becomes greater for NM studies in pediatrics population. The way to collect data, the mode to organize the information and analyze it, has also undergone changes, mainly with radiation dose management systems. In CT and interventional studies, the grouping by anatomical locations is being constrained or modulated by clinical indications with analogous image quality requirements for proper diagnosis. Something similar happens in MN, where the incorporation of activity/patient's weight is envisioned as NRD for hybrid technologies and pediatric studies. In general, the study showed that, the scientific paper's availability about DRL for adult population are much wider. More pediatric studies on these subjects are needed, especially in NM
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Humanos , Doses de Radiação , Níveis de Referência de Diagnóstico , Medicina NuclearRESUMO
BACKGROUND: We use national surveillance data to evaluate race/ethnicity by sex/gender differences and trends in substance use treatment admissions and overdose deaths involving opioid and stimulant use. METHODS: We used data (1992-2019) from the Treatment Episode Dataset-Admissions to identify treatment admissions and the Center for Disease Control and Prevention's Wide-Ranging Online Data for Epidemiologic Research (1999-2020) to identify overdose deaths. We assessed treatment admissions and related drug overdose deaths per 100,000 adults by sex and race/ethnicity for opioid and stimulant groups: cocaine, opioid, methamphetamines, cocaine and opioid use, cocaine and methamphetamines, and opioid and methamphetamines. RESULTS: We found significant variations in treatment admissions and deaths by race/ethnicity and sex/gender. Cocaine-related treatment admissions and deaths were most prevalent among Non-Hispanic Black individuals over the study years, yet lower rates were evident among individuals from other racial/ethnic groups. Notably, Non-Hispanic Black men experienced larger increases in cocaine-only admissions than men of other racial/ethnic groups between 1992 and 2019. Men had higher opioid and stimulant treatment admissions and overdose deaths than women. We observed skyrocketing methamphetamine deaths among American Indian/Native Alaskan men and women from 1992 to 2019. DISCUSSION: Steep increases in overdose deaths fueled by methamphetamines among Non-Hispanic Native Americans and cocaine among Non-Hispanic Black individuals suggest a need for more effective interventions to curb stimulant use. Variations by race/ethnicity and sex/gender also suggest interventions should be developed through an intersectionality lens.
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Cocaína , Overdose de Drogas , Metanfetamina , Transtornos Relacionados ao Uso de Opioides , Adulto , Masculino , Humanos , Feminino , Analgésicos Opioides , Overdose de Drogas/epidemiologia , Etnicidade , Transtornos Relacionados ao Uso de Opioides/epidemiologia , Transtornos Relacionados ao Uso de Opioides/terapiaRESUMO
OBJECTIVE: The COVID-19 pandemic disrupted sexual health services for young people, with potential consequences of decreasing preventive screening and increasing undiagnosed sexually transmitted infections (STIs). This study aimed to assess trends in asymptomatic screening among patients receiving STI testing and to estimate the number of STI cases that were missed during the early months of the pandemic. STUDY DESIGN: A cross-sectional study of electronic health records for chlamydia, gonorrhea, and trichomonas testing encounters from six pediatric primary care clinics in Philadelphia, July 2014 to November 2020. METHODS: A total of 35,548 testing encounters were analyzed, including 2958 during the pandemic. We assessed whether testing at each encounter was performed as asymptomatic screening, risk-based testing, or symptomatic testing. We evaluated screening trends over time and estimated the number of missed STI cases during the pandemic. RESULTS: The mean monthly testing encounters decreased from 479 per month prepandemic to 329 per month during the pandemic. The percent of tests performed as asymptomatic screening dropped from 72.5% prepandemic to a nadir of 54.5% in April 2020. We estimate that this decrease in asymptomatic screening would represent 159 missed cases (23.8% of expected cases) based on patient volume from the previous year. CONCLUSIONS: During the pandemic, the total volume of STI testing encounters and the proportion of tests performed as asymptomatic screening decreased, potentially resulting in missed diagnoses. Undiagnosed STIs can result in severe sequelae and contribute to community transmission of STIs. Efforts are needed to re-establish and sustain access to STI services for adolescents in response to disruptions caused by the pandemic.
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COVID-19 , Infecções Sexualmente Transmissíveis , Humanos , Criança , Adolescente , COVID-19/diagnóstico , COVID-19/epidemiologia , Pandemias , Estudos Transversais , Philadelphia/epidemiologia , Infecções Sexualmente Transmissíveis/diagnóstico , Infecções Sexualmente Transmissíveis/epidemiologiaRESUMO
X-ray bone semantic segmentation is one crucial task in medical imaging. Due to deep learning's emergence, it was possible to build high-precision models. However, these models require a large quantity of annotated data. Furthermore, semantic segmentation requires pixel-wise labeling, thus being a highly time-consuming task. In the case of hip joints, there is still a need for increased anatomic knowledge due to the intrinsic nature of the femur and acetabulum. Active learning aims to maximize the model's performance with the least possible amount of data. In this work, we propose and compare the use of different queries, including uncertainty and diversity-based queries. Our results show that the proposed methods permit state-of-the-art performance using only 81.02% of the data, with O ( 1 ) time complexity.
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The Standard Cosmological Model has experienced tremendous success at reproducing observational data by assuming a universe dominated by a cosmological constant and dark matter in a flat geometry. However, several studies, based on local measurements, indicate that the universe is expanding too fast, in disagreement with the Cosmic Microwave Background. Taking into account combined data from CMB, Baryon Acoustic Oscillation, and type Ia Supernovae, we show that if the mechanism behind the production of dark matter particles has at least a small non-thermal origin, one can induce larger values of the Hubble rate [Formula: see text], within the [Formula: see text]CDM, to alleviate the trouble with [Formula: see text]. In the presence of non-standard cosmology, however, we can fully reconcile CMB and local measurements and reach [Formula: see text]-74 [Formula: see text].
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OBJECTIVES: This systematic review study and meta-analysis sought to estimate the prevalence of malnutrition and nutritional deficiencies in children with cerebral palsy (CP). STUDY DESIGN: This is a systematic review and meta-analysis. METHODS: The systematic review was conducted according to the PRISMA guidelines. The articles were chosen using the PubMed, Embase, Scopus, Web of Science, Cochrane Library, SciELO, and Lilacs databases and the bibliographical reference lists of the articles. No limitations were placed on the time of publication, but the articles had to include children from 0 to 18 years old with CP who presented the prevalence of malnutrition and nutritional deficiencies. The methodological quality of the articles was assessed using the verification list for analytical cross-sectional studies, the Newcastle-Ottawa scale, and the Cochrane Collaboration tool for randomized studies. The meta-analysis of proportions was conducted based on the prevalence data for malnutrition or nutritional deficiencies. The study is registered in PROSPERO under CRD number 42020175068. RESULTS: Sixty-seven articles (N = 453,804) published between 1986 and 2019 were included. Most of the articles presented a low risk of bias and no publication was excluded for quality reasons. The most widely used anthropometric index for diagnosing nutritional status was weight-to-age and the estimated prevalence of malnutrition was 40% (95% CI = 28.0-53.0). Nutrient deficiency was investigated by nine publications, with hypocalcemia and reduced serum concentrations of zinc, copper, and vitamin D being reported the most. CONCLUSIONS: We found a high rate of malnutrition in the population in this review, moreover, we suggest that some nutritional deficiencies are associated with food deficit and that the socio-economic and age factors of these children may relate with the poor nutritional outcome. This makes monitoring and personalized nutritional management necessary, in accordance with the characteristics and particularities of children with CP.
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Paralisia Cerebral , Desnutrição , Adolescente , Fatores Etários , Paralisia Cerebral/complicações , Paralisia Cerebral/epidemiologia , Criança , Pré-Escolar , Estudos Transversais , Humanos , Lactente , Recém-Nascido , Desnutrição/epidemiologia , Estado NutricionalRESUMO
PURPOSE: To evaluate the efficacy and safety of oral estrogen therapy in female patients of childbearing age with uncontrolled acromegaly and to verify the significance of the presence of estrogen receptor α (ER-α) in somatotropinomas. METHODS: Prospective study in which biochemical and radiological evaluations were performed at baseline and after six months of treatment with an oral formulation of ethinyl-estradiol 0.03 mg and levonorgestrel 0.15 mg. ER-α was assessed by immunohistochemistry and immunopositivity was considered when it was present in ≥ 1% of cells. RESULTS: Eight patients with uncontrolled acromegaly were selected. All patients underwent surgery. Four patients were on octreotide LAR 30 mg, two patients were on lanreotide autogel 120 mg, and two patients had active disease after surgery. At the end of follow-up, IGF-I normalized in 3/8 (37%), 2/8 (25%) patients presented with mean IGF-I reduction of 25% but without IGF-I normalization, and 2/8 (25%) did not respond-one had a 13% increase in IGF-I and IGF-I level remained unchanged after treatment in the other. In one patient, treatment was discontinued after 3 months due to side effects (headache), with an IGF-I reduction of 28% but without normalization. Tumor volume increase (41%) was observed in only one patient (the only tumor with positive ER-α expression). CONCLUSIONS: In uncontrolled patients with acromegaly, a trial with oral estrogen can be an option for young women. Oral estrogen was well tolerated, but the somatotropinoma that presented ER-α expression was the only somatotropinoma that presented growth during treatment.
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Acromegalia , Adenoma , Hormônio do Crescimento Humano , Acromegalia/tratamento farmacológico , Acromegalia/cirurgia , Adenoma/tratamento farmacológico , Preparações de Ação Retardada/uso terapêutico , Estrogênios/uso terapêutico , Feminino , Hormônio do Crescimento Humano/metabolismo , Hormônio do Crescimento Humano/uso terapêutico , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Octreotida/uso terapêutico , Peptídeos Cíclicos/uso terapêutico , Estudos Prospectivos , Somatostatina/uso terapêutico , Resultado do TratamentoRESUMO
Videolaryngoscopes are thought to improve glottic view and facilitate tracheal intubation compared with the Macintosh direct laryngoscope. However, we currently do not know which one would be the best choice in most patients undergoing anaesthesia. We designed this systematic review with network meta-analyses to rank the different videolaryngoscopes and the Macintosh direct laryngoscope. We conducted searches in PubMed and a further five databases on 11 January 2021. We included randomised clinical trials with patients aged ≥16 years, comparing different videolaryngoscopes, or videolaryngoscopes with the Macintosh direct laryngoscope for the outcomes: failed intubation; failed first intubation attempt; failed intubation within two attempts; difficult intubation; percentage of glottic opening seen; difficult laryngoscopy; and time needed for intubation. We assessed the quality of evidence according to GRADE recommendations and included 179 studies in the meta-analyses. The C-MAC and C-MAC D-Blade were top ranked for avoiding failed intubation, but we did not find statistically significant differences between any two distinct videolaryngoscopes for this outcome. Further, the C-MAC D-Blade performed significantly better than the C-MAC Macintosh blade for difficult laryngoscopy. We found statistically significant differences between the laryngoscopes for time to intubation, but these differences were not considered clinically relevant. The evidence was judged as of low or very low quality overall. In conclusion, different videolaryngoscopes have differential intubation performance and some may be currently preferred among the available devices. Furthermore, videolaryngoscopes and the Macintosh direct laryngoscope may be considered clinically equivalent for the time taken for tracheal intubation. However, despite the rankings from our analyses, the current available evidence is not sufficient to ensure significant superiority of one device or a small set of them over the others for our intubation-related outcomes.
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Intubação Intratraqueal/métodos , Laringoscopia/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Técnicas e Procedimentos Assistidos por Vídeo , Adulto , Humanos , Intubação Intratraqueal/normas , Laringoscopia/normas , Metanálise em Rede , Ensaios Clínicos Controlados Aleatórios como Assunto/normasRESUMO
Additives used to improve feed efficiency of beef cattle on high-grain diets requires products that not only increase animal performance but also provide food safety for consumers. Since phytogenic additives such as essential oils (EO) are the main substitutes for monensin in the diet of cattle fed high-grain diets, this study aimed to evaluate, through meta-analysis, the effects of EO as an alternative to monensin in diets for beef cattle on feed intake, performance, carcass characteristics and ruminal fermentative parameters. Ten peer-reviewed publications with 27 treatment means were included in the data set. These effects were evaluated using random-effect models to examine the weighted mean differences (WMD) between EO treatment and control treatment (diets with monensin). Heterogeneity was explored by meta-regression and subgroup analysis. The substitution of EO for monensin did not affect methane production, ruminal pH values, average daily gain, feed efficiency or carcass weight. However, carcass dressing percentage (WMD = 0.38%; P = 0.03), ribeye area (WMD = 0.82 cm2; P < 0.0001) and subcutaneous fat thickness (WMD = 0.56 mm; P < 0.0001) values increased. Although the use of EO instead of monensin had no influence on the performance of beef cattle fed high-grain diets, the prevalence of hepatic abscesses increased 84.9% and the replacement of monensin by EO increased the risk ratio of hepatic abscess prevalence by 107%. Therefore, the use of EO in high-grain beef cattle diets was ineffective in protecting the liver against abscesses.
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Bovinos/fisiologia , Dieta/veterinária , Monensin/administração & dosagem , Óleos Voláteis/administração & dosagem , Ração Animal/análise , Animais , Doenças dos Bovinos/epidemiologia , Digestão , Ingestão de Alimentos , Grão Comestível , Fermentação , Aditivos Alimentares , Abscesso Hepático/epidemiologia , Abscesso Hepático/veterinária , Rúmen/metabolismoRESUMO
A series of 18 2-arylidene indan-1,3-dione derivatives was synthesized and tested against Daphnia magna to assess the environmental toxicity of these compounds. Aiming to investigate the toxicity mechanism for this series of compounds, a four-dimensional quantitative structure-activity analysis (4D-QSAR) was performed through the partial least square regression (PLS). The best PLS model was built with two factors and the selected field descriptors, of Coulomb (C) and Lennard-Jones (L) nature, describing 77.43% of variance and presenting the following statistics: r 2 = 0.89; SEC = 0.30; Q 2 = 0.81; SEV = 0.36. According to the literature, the bioactivity of α,ß-unsaturated ketones, a functionality present in the series of compounds under investigation, is related to the conjugated double bond with the carbonyl group. The presence of a positive Coulomb descriptor nearby the carbonyl moieties, obtained as a result of the regression model, indicates that these polar groups are also related to the toxicity on D. magna. From the PLS regression model, the toxicity EC50-48 h values increases with the positive Coulomb descriptor and diminishes with the negative Lennard-Jones descriptors. It could be concluded that the presence of small polar groups in the aromatic ring of the arylidene moiety tends to increase the toxicity, while bulkier apolar substituents lead to a decrease of the toxicity.
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Daphnia/efeitos dos fármacos , Indanos/toxicidade , Relação Quantitativa Estrutura-Atividade , Poluentes Químicos da Água/toxicidade , Animais , Indanos/química , Poluentes Químicos da Água/químicaRESUMO
The use of rosemary essential oil (RO) and its combination with nisin (RO+N) in preventing the multiplication of Alicyclobacillus acidoterrestris in orange juice was evaluated. The minimum inhibitory and bactericidal concentrations (MIC and MBC) for RO were both 125 µg ml-1 while RO+N displayed a synergistic effect. The use of RO and RO+N at concentrations of 1, 4 and 8× MIC in orange juice for 96 h was evaluated in terms of their sporicidal effectiveness. With regard to the action against A. acidoterrestris spores, RO at 8× MIC was sporostatic, whereas RO+N at 1× MIC was sporicidal. Morphological changes in the structure of the micro-organism after treatment were also observed by microscopy. Furthermore, flow cytometric analysis showed that most cells were damaged or killed after treatment. In general, the antioxidant activity after addition of RO+N decreased with time. The results demonstrate that using the combination of RO and nisin can prevent the A. acidoterrestris growth in orange juice.
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Alicyclobacillus/crescimento & desenvolvimento , Antibacterianos/farmacologia , Sucos de Frutas e Vegetais/microbiologia , Nisina/farmacologia , Óleos Voláteis/farmacologia , Rosmarinus/química , Alicyclobacillus/efeitos dos fármacos , Citrus sinensisRESUMO
Herbivory is one of the major biotic stress factors that affect the establishment of plants. However, the main factors that drive herbivory in seedlings of Amazonian tree species are still not well understood. Here we investigated whether contrasting levels of irradiance influence herbivory according to different herbivory indicators and which leaf traits are most related to interspecific variation in herbivory under contrasting irradiance conditions. We measured the leaf area lost as a result of insect herbivory in five tree species planted in a silvicultural system of secondary forest enrichment according to two indicators, herbivore damage (accumulated since plant germination) and herbivory rate (measured over time), and two irradiance conditions, understorey PPFD 2.6 mol·m-2 ·day-1 ) and gap PPFD 33.1 mol·m-2 ·day-1 . Furthermore, we related the interspecific variation in herbivory to a set of leaf traits: SLA, RWC, sclerophylly, phenolic compound content, tannins, condensed tannins and non-structural carbohydrates. Herbivore damage was significantly affected by light availability and species, with the highest percentage variation observed in the Meliaceae (Carapa guianensis and Swietenia macrophylla). For the herbivory rate, only the interspecific variation was significant, with Bertholletia excelsa having the lowest rates. Chemical characteristics (phenolic compounds and tannins) were most related to herbivory rates, as well as highly influenced by light conditions. Non-structural carbohydrates (starch and sucrose) were also related to the interspecific variation in herbivory. The phenolic compounds and starch, as affected by light quantity, are species dependent. Thus, the selective pressure on herbivores may be driven by species-dependent responses to light conditions.
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Herbivoria , Folhas de Planta , Árvores , Animais , Herbivoria/efeitos da radiação , Insetos/fisiologia , Fenótipo , Folhas de Planta/anatomia & histologia , Folhas de Planta/metabolismo , Folhas de Planta/efeitos da radiação , Luz Solar , Árvores/anatomia & histologia , Árvores/efeitos da radiaçãoRESUMO
Listeria monocytogenes is an opportunistic pathogen with the ability to adapt to different environmental conditions, resulting in safety issues for food producers. Foods contaminated by L. monocytogenes can represent a risk if consumed by susceptible individuals such as elderly, pregnant women and the immunocompromised. The aim of this study was to evaluate the genetic diversity of a collection of L. monocytogenes isolated from different matrices in Brazil during the period of 1979-2015. A total of 51 L. monocytogenes serotype 1/2a strains isolated from clinical samples (n = 3) and food samples (n = 48) were characterized by Multi-Virulence-Locus Sequence Typing (MVLST). The strains were assigned to nine virulence types (VT): VT-11 (n = 3, 5·9%), VT-45 (n = 27, 52·9%), VT-59 (n = 11, 21·6%), VT-68 (n = 3, 5·9%), VT-94 (n = 2, 3·9%), VT-107 (n = 2, 3·9%), VT-184 (n = 1, 1·9%), VT-185 (n = 1, 1·9%) and VT-186 (n = 1, 1·9%); and four of them (VT-11, VT-45, VT-59 and VT-68) have already been associated with cases of listeriosis worldwide. The VT-11, VT-59 (Epidemic Clone V) and VT-186 were identified in blood culture samples, as well as in different classes of foods. It is recommended that the epidemiological surveillance agencies evaluate the risk that foods contaminated with L. monocytogenes VTs pose to susceptible populations.