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1.
Sci Rep ; 14(1): 8495, 2024 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605161

RESUMO

A worldwide increase in the prevalence of coral diseases and mortality has been linked to ocean warming due to changes in coral-associated bacterial communities, pathogen virulence, and immune system function. In the Mediterranean basin, the worrying upward temperature trend has already caused recurrent mass mortality events in recent decades. To evaluate how elevated seawater temperatures affect the immune response of a thermophilic coral species, colonies of Astroides calycularis were exposed to environmental (23 °C) or elevated (28 °C) temperatures, and subsequently challenged with bacterial lipopolysaccharides (LPS). Using immunolabeling with specific antibodies, we detected the production of Toll-like receptor 4 (TLR4) and nuclear factor kappa B (NF-kB), molecules involved in coral immune responses, and heat shock protein 70 (HSP70) activity, involved in general responses to thermal stress. A histological approach allowed us to characterize the tissue sites of activation (epithelium and/or gastroderm) under different experimental conditions. The activity patterns of the examined markers after 6 h of LPS stimulation revealed an up-modulation at environmental temperature. Under warmer conditions plus LPS-challenge, TLR4-NF-kB activation was almost completely suppressed, while constituent elevated values were recorded under thermal stress only. An HSP70 up-regulation appeared in both treatments at elevated temperature, with a significantly higher activation in LPS-challenge colonies. Such an approach is useful for further understanding the molecular pathogen-defense mechanisms in corals in order to disentangle the complex interactive effects on the health of these ecologically relevant organisms related to global climate change.


Assuntos
Antozoários , Animais , Antozoários/fisiologia , Receptor 4 Toll-Like , Aquecimento Global , Lipopolissacarídeos , NF-kappa B , Água do Mar , Temperatura , Recifes de Corais
2.
Mar Pollut Bull ; 201: 116287, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38547612

RESUMO

Specimens of the Mediterranean sea anemone Anemonia viridis were exposed to methylmercury (MeHg) and bacterial infection to study their immune responses to a well-known toxic pollutant. Anemones were housed in laboratory conditions and divided into five experimental groups: 1. control (no microinjection); 2. filtered seawater + buffer injection; 3. filtered seawater + Escherichia coli injection; 4. MeHg + buffer injection; 5. MeHg + E. coli injection. Data showed an increase in antioxidant enzyme production compared to the constitutive condition, while methylmercury inhibited lysozyme production. The buffer inoculation had no statistically significant effects on the animals. In addition, electrophoretic and protease analyses revealed differences in the type of proteins produced, as well as a modulation of proteases depending on the treatment. The study demonstrated the immunomodulatory effect of the organic pollutant on A. viridis, validating its use as a model organism for marine coastal biomonitoring programmes and multiple stress studies.


Assuntos
Infecções Bacterianas , Poluentes Ambientais , Compostos de Metilmercúrio , Anêmonas-do-Mar , Animais , Compostos de Metilmercúrio/toxicidade , Compostos de Metilmercúrio/metabolismo , Anêmonas-do-Mar/fisiologia , Escherichia coli , Poluentes Ambientais/metabolismo
3.
Health Educ Res ; 38(1): 1-12, 2023 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-36367205

RESUMO

Diabetes is a chronic condition that has reached epidemic proportions in the United States, affecting nearly 34 million adults, and disproportionately affecting vulnerable populations, such as ethnic minorities, the elderly and individuals with low socioeconomic status. This study addresses the impact of the Health Extension for Diabetes (HED) program, a community-based diabetes self-management support program, on adult diabetes self-care behaviors. The Summary of Diabetes Self-Care Activities (SDSCA) was utilized to evaluate improvement in diabetes self-care behaviors. Descriptive statistics, univariate and multivariable regression models were conducted. Significant increases were observed among program participants (N = 149) in all five subscales of the SDSCA (general diet, specific diet, blood glucose testing, exercise and foot care; P-values < 0.001). A priority of this diabetes education program was helping underserved populations; over half (62%) of participants self-identified as Black/African Americans. After program participation, scores on all SDSCA subscales increased significantly among Black/African Americans (n = 93) by approximately 1 day per week. White/other races (n = 56) showed similar increases in four of the SDSCA subscales post-HED program participation. This study shows that increasing participation in community-based, diabetes self-management support programs, such as HED, can increase engagement in diabetes self-care behaviors among underserved groups.


Assuntos
Diabetes Mellitus Tipo 2 , Diabetes Mellitus , Autogestão , Humanos , Adulto , Estados Unidos , Idoso , Autocuidado , Diabetes Mellitus/terapia , Comportamentos Relacionados com a Saúde , Dieta , Diabetes Mellitus Tipo 2/terapia
4.
Rev Sci Instrum ; 93(11): 113512, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36461481

RESUMO

Dedicated nuclear diagnostics have been designed, developed, and built within EUROFUSION enhancement programs in the last ten years for installation at the Joint European Torus and capable of operation in high power Deuterium-Tritium (DT) plasmas. The recent DT Experiment campaign, called DTE2, has been successfully carried out in the second half of 2021 and provides a unique opportunity to evaluate the performance of the new nuclear diagnostics and for an understanding of their behavior in the record high 14 MeV neutron yields (up to 4.7 × 1018 n/s) and total number of neutrons (up to 2 × 1019 n) achieved on a tokamak. In this work, we will focus on the 14 MeV high resolution neutron spectrometers based on artificial diamonds which, for the first time, have extensively been used to measure 14 MeV DT neutron spectra with unprecedented energy resolution (Full Width at Half Maximum of ≈1% at 14 MeV). The work will describe their long-term stability and operation over the DTE2 campaign as well as their performance as neutron spectrometers in terms of achieved energy resolution and high rate capability. This important experience will be used to outline the concept of a spectroscopic neutron camera for the SPARC tokamak. The proposed neutron camera will be the first one to feature the dual capability to measure (i) the 2.5 and 14 MeV neutron emissivity profile via the conventional neutron detectors based on liquid or plastics scintillators and (ii) the 14 MeV neutron spectral emission via the use of high-resolution diamond-based spectrometers. The new opportunities opened by the spectroscopic neutron camera to measure plasma parameters will be discussed.

5.
Mar Pollut Bull ; 181: 113833, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35716492

RESUMO

We report the Sabella spallanzanii mucus bacterial agglutination response after inorganic arsenic (As) exposure. As is actively adsorbed from the surrounding environment and accumulated at high concentrations in tissues as an anti-predatory strategy. Here we investigated the effect of high As concentrations on its immunobiological response. It may act on mucus lectins and on its ability to agglutinate bacteria. We concluded that As at high concentrations leads to the inhibition of pathogen recognition. Nevertheless, although its biological activity is significant reduced in winter, responses to As concentrations are very similar, and below a certain threshold do not induce alterations, supporting the hypothesis of adaptation to high As concentrations related to involvement in predation defence.


Assuntos
Arsênio , Poliquetos , Animais , Arsênio/toxicidade , Bactérias , Imunidade , Muco , Comportamento Predatório
6.
Fish Shellfish Immunol ; 127: 109-118, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35697269

RESUMO

Filter-feeding bivalves, such as the Mytilus species, are exposed to different types of bacteria in the surrounding waters, in particular of the Vibrio genus. Mussels lack an adaptive immune system and hemocytes can recognize pathogen-associated molecular patterns (PAMPs) via pattern recognition receptors (PRRs) to activate intracellular signaling pathways to trigger the antimicrobial effectors synthesis. Among the areas of bivalve immunity that deserve study include the role of hemocyte subpopulations. Since little information are available on immune responses at the tissue level to human pathogenic vibrios commonly detected in coastal waters involved in seafood-borne diseases, in this work, immunological parameters of the hemocytes from the Mediterranean mussel M. galloprovincialis were evaluated in response to in vivo challenge with Vibrio splendidus. The histological approach has been first used in order to identify the hemocytes recruitment at the infection site and the morphological change of muscular fibers. In addition, using immunolabeling with specific antibody we detected the production of molecules involved in the inflammatory activated cascade: Toll-like receptors 4 (TLR4), the myeloid differentiation factor 88 (MyD88), the Allograft inflammatory factor-1 (AIF-1) and the ribonucleases RNASET2, belonging to the T2 family, that in vertebrates are involved in the recruitment and activation of macrophages. Our results indicate the activation of TLR4 during bacterial infection preparatory to the recruitment of the MyD88 adapter with a putative role in recognition and intracellular signalling. Furthermore, the data presented in this work suggest that challenging with Gram-negative bacteria causes a massive migration of AIF-1+ hemocytes and that the ribonuclease RNASET2 could play a key role in the recruitment of these activated hemocytes. Our approach is useful for further understanding the complex molecular defence mechanisms of the host in invertebrates, especially in relation to the need to develop methods to evaluate the immunological response of bivalve molluscs used in aquaculture.


Assuntos
Mytilus , Vibrioses , Vibrio , Animais , Hemócitos , Humanos , Fator 88 de Diferenciação Mieloide/metabolismo , Ribonucleases/metabolismo , Alimentos Marinhos , Receptor 4 Toll-Like/metabolismo , Proteínas Supressoras de Tumor , Vibrio/fisiologia , Vibrioses/metabolismo
8.
Clin Oncol (R Coll Radiol) ; 33(12): 788-794, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34176711

RESUMO

AIMS: We assessed the efficacy and safety of total neoadjuvant therapy, including targeted agent plus FOLFOXIRI (5-fluorouracil, leucovorin, oxaliplatin and irinotecan) induction chemotherapy followed by intensified chemoradiotherapy (CRT) and surgical resection, in patients with locally advanced rectal cancer. MATERIALS AND METHODS: This was a single-arm, single-centre phase II trial. Eligible patients had non-metastatic locally advanced rectal adenocarcinoma. Based on Ras-BRAF status, patients were treated with bevacizumab (mutated Ras-BRAF) or panitumumab/cetuximab (wild-type Ras-BRAF) plus FOLFOXIRI regimen followed by oxaliplatin-5-fluorouracil-based CRT and surgery. The primary end point was pathological complete response rate. Secondary end points were toxicity, compliance, tumour downstaging, complete resection, surgical complications, local and distant failures and overall survival. The sample size was planned to expect an absolute 20% improvement in pathological complete response rate over historical literature data with an α error of 0.05 and a power of 80%. RESULTS: Between October 2015 and September 2019, 28 patients (median age 66 years) were enrolled. All patients had regional lymph node involvement at diagnosis. FOLFOXIRI plus bevacizumab was administered in 11 mutated Ras-BRAF patients, whereas the 17 wild-type Ras-BRAF patients received FOLFOXIRI plus panitumumab/cetuximab. Overall, total neoadjuvant therapy was well tolerated and 26 patients (92.9%) completed the programmed strategy. A complete response was achieved in nine cases (32.1%) and a nearly pathological complete response (ypT1 ypN0) in two patients (7.2%). There was no evidence of febrile neutropenia and no grade 4 adverse events were recorded. Radical resection was achieved in all cases. CONCLUSION: FOLFOXIRI plus targeted agent-based induction chemotherapy and intensified CRT before surgery showed promising clinical activity and was well tolerated in locally advanced rectal cancer patients. This phase II trial provides a strong rationale for phase III studies.


Assuntos
Terapia Neoadjuvante , Neoplasias Retais , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Fluoruracila , Humanos , Leucovorina , Neoplasias Retais/tratamento farmacológico
9.
Sci Rep ; 11(1): 9679, 2021 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-33958604

RESUMO

There is not in Argentina publications regarding the presentation of patients with COVID-19 requiring hospitalized and emergency care in vulnerable populations (lower incomes and less education tend at greater risk for poor health status and healthcare access), and it has few reports in developing countries. The objective is to determine whether in the care of vulnerable patients, to succeed against COVID-19, multiple public health tools and interventions will be needed to minimize morbidity and mortality. The study is a prospective cohort investigation of patients with lab-confirmed COVID-19, who required to any of the Health Centers response from April 8, 2020, to August 18, 2020. In Buenos Aires Metropolitan Area (AMBA), April 8, 2020 the virus was identified in patients hospitalized in the "Southeast Network" (SN), AMBA. SN covering an area of 661 square kilometers, with 1.8 million inhabitants residing in urban, and rural areas. A total of 14 health centers with different levels of care complexity provide care to patients in the region. The information of each patient with COVID-19 evaluated by SN, was incorporated in an Epidemiological Dashboard. The investigation was designed and reported with consideration of observational studies in epidemiology. We describe the hospitals presentation and care of persons who required SN response and were ultimately diagnosed with COVID-19. From April 8, 2020, to August 18, 2020, were included 1495 patients with lab-confirmed COVID-19 in SN. A total of 58% patients were men, and the mean age (SD) was 48.9 (15.59) years. Eighty one percent patients with pre-existing diseases, most frequent hypertension and diabetes, but hypertension, chronic lung disease, and cardiovascular disease presented higher risk. A total of 13% were hospitalized in Intensive Therapy Unit. The mortality of the cohort was 9.77%. Mortality was higher for patients aged 65 or more (OR 5.09), and for those had some pre-existing disease (OR 2.61). Our observations are consistent with reports demonstrating older persons, and those with comorbidities have the highest risk of mortality related to COVID-19. However, unlike other reports from developed or some developing countries, the mortality in our study is lower. This finding may be related to age of our cohort is younger than other published. Also, the health system was able to respond to the demand.


Assuntos
COVID-19/diagnóstico , COVID-19/epidemiologia , SARS-CoV-2/isolamento & purificação , Adulto , Idoso , Argentina/epidemiologia , COVID-19/mortalidade , Feminino , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Saúde Pública , Populações Vulneráveis
10.
Mar Environ Res ; 168: 105292, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33756251

RESUMO

Anthropogenic pressure adds up and interacts with the effects of climate change with a varying magnitude and potential changes depend on species' Life History (LH) traits, local environmental conditions and co-occurrence of several stressors. Stressors exert negative effects on marine biota when acting as a single factor, but the effects may be amplified when more than one stressor work in combination, producing interacting effects on biodiversity and ecosystem functioning. The impairment of individual functional traits (FT) leads to strong rebounds on LH traits and this may have ecological consequences. No studies actually relate FT and antioxidant enzymes to multiple environmental stressors. In this paper we investigate the effects of food concentration, temperature and hypoxia on metabolic traits as expressed by a proxy such as respiration rate and feeding behaviour and on antioxidant enzymes (Catalase, Superoxide dismutase, Glutathione S-Transferase, Glutathione peroxidase) for the bivalve Mytilus galloprovincialis. Mussels were exposed to three temperatures (12, 20 and 28 °C) under normoxic (8 mg O2 l-1) and hypoxic (~2 mg O2 l-1) conditions, with varying food concentrations ranging from 0.9 to 3.5 µg of chlorophyll l-1. The results show that FTs and antioxidant enzymes were affected by temperature, hypoxia and food availability, and outcome allowed us to emphasise that a multi-scalar integrated approach is suitable to detect and monitor effects of anthropogenic disturbance on ecosystem functioning.


Assuntos
Mytilus , Poluentes Químicos da Água , Animais , Antioxidantes , Biomarcadores , Catalase , Ecossistema , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
11.
Conserv Physiol ; 8(1): coaa005, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32099655

RESUMO

Increasingly, cold-water pollution (CWP) is being recognised as a significant threat to aquatic communities downstream of large, bottom-release dams. Cold water releases typically occur during summer when storage dams release unseasonably cold and anoxic hypolimnetic waters, which can decrease the temperature of downstream waters by up to 16°C. Depending on the release duration, these hypothermic conditions can persist for many months. The capacity of ectothermic species to tolerate or rapidly adjust to acute temperature changes may determine the nature and magnitude of the impact of CWP on affected species. This study assessed the impacts of an acute reduction in water temperature on the physiological function and locomotor performance of juvenile silver perch (Bidyanus bidyanus) and examined their capacity to thermally compensate for the depressive effects of low temperatures via phenotypic plasticity. Locomotor performance (Ucrit and Usprint) and energetic costs (routine and maximum metabolic rate) were measured at multiple points over a 10-week period following an abrupt 10°C drop in water temperature. We also measured the thermal sensitivity of metabolic enzymes from muscle samples taken from fish following the exposure period. Cold exposure had significant depressive effects on physiological traits, resulting in decreases in performance between 10% and 55%. Although there was partial acclimation of Ucrit (~35% increase in performance) and complete compensation of metabolic rate, this occurred late in the exposure period, meaning silver perch were unable to rapidly compensate for the depressive effects of thermal pollution. The results of this study have substantial implications for the management of cold water releases from large-scale dams and the conservation of native freshwater fish species, as this form of thermal pollution can act as a barrier to fish movement, cause reduced recruitment, ecological community shifts and disruptions to timing and success of reproduction.

12.
J Cancer Res Clin Oncol ; 146(3): 761-765, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31784835

RESUMO

PURPOSE: To analyse the classification performances of a decision tree method applied to predictor variables in survival outcome in patients with locally advanced rectal cancer (LARC). The aim was to offer a critical analysis to better apply tree-based approach in clinical practice and improve its interpretation. MATERIALS AND METHODS: Data concerning patients with histological proven LARC between 2007 and 2014 were reviewed. All patients were treated with trimodality approach with a curative intent. The Kaplan-Meier method was used to estimate overall survival (OS). Decision tree methods were was used to select important variables in outcome prediction. RESULTS: A total of 100 patients were included. The 5-year and 7-year OS rates were 76.4% and 71.3%, respectively. Age, co-morbidities, tumor size, clinical tumor classification (cT) and clinical nodes classification (cN) were the important predictor variables to the tree's construction. Overall, 13 distinct groups of patients were defined. Patients aged < 65 years with cT3 disease and elderly patients with a tumor size < 5 cm seemed to have highest rates of survival. But the process over-fitted the data, leading to poor algorithm performance. CONCLUSION: We proposed a decision tree algorithm to identify known and new pre-treatment clinical predictors of survival in LARC. Our analysis confirmed that tree-based machine learning method, especially classification trees, can be easily interpreted even by a non-expert in the field, but controlling cross validation errors is mandatory to capture its statistical power. However, it is necessary to carefully analyze the classification error trend to chose the important predictor variables, especially in little data. Machine learning approach should be considered the new unexplored frontier in LARC. Based on big datasets, decision trees represent an opportunity to improve decision-making process in clinical practice.


Assuntos
Árvores de Decisões , Aprendizado de Máquina , Neoplasias Retais/classificação , Neoplasias Retais/mortalidade , Neoplasias Retais/patologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
13.
Curr Oncol ; 26(3): e300-e308, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31285672

RESUMO

Background: Commonly used first-line (1L) chemotherapies for patients with advanced squamous-cell lung cancer (scc) include gemcitabine-platinum (gp), nab-paclitaxel-carboplatin (nabpc), and sb-paclitaxel-carboplatin (sbpc) regimens. However, no head-to-head trials have compared those treatments. In the present study, we compared the efficacy of 1L gp, nabpc, and sbpc in patients with scc and in patients with scc who subsequently received second-line (2L) immunotherapy. Methods: Medical records of patients who initiated the 1L treatments of interest between June 2014 and October 2015 were reviewed by 132 participating physicians. Kaplan-Meier curves were used to evaluate overall survival (os), progression-free survival (pfs), and treatment discontinuation (td), and then Cox proportional hazards regression was used to compare the results between the cohorts. Results: Medical records of 458 patients with scc receiving gp (n = 139), nabpc (n = 159), or sbpc (n = 160) as 1L therapy were reviewed. Median os was longer with nabpc (23.9 months) than with gp (16.9 months; adjusted hazard ratio vs. nabpc: 1.55; p < 0.05) and with sbpc (18.3 months; adjusted hazard ratio: 1.42; p = 0.10). No differences were observed in pfs (median pfs: 8.8, 8.0, and 7.6 months for gp, nabpc, and sbpc respectively; log-rank p = 0.76) or in td (median td: 5.5, 5.7, and 4.6 months respectively; p = 0.65). For patients who subsequently received 2L immunotherapy, no differences in os were observed (median os: 27.3, 25.0, and 23.0 months respectively; p = 0.59). Conclusions: In a nationwide sample of scc patients, longer median os was associated with 1L nabpc than with gp and sbpc. Median os for all 1L agents considered was similar in the subgroup of patients who sequenced to a 2L immunotherapy.


Assuntos
Albuminas/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carboplatina/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma de Células Escamosas/tratamento farmacológico , Desoxicitidina/análogos & derivados , Neoplasias Pulmonares/tratamento farmacológico , Paclitaxel/uso terapêutico , Idoso , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Desoxicitidina/uso terapêutico , Feminino , Humanos , Imunoterapia , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida , Resultado do Tratamento , Gencitabina
14.
Int J Food Microbiol ; 292: 150-158, 2019 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-30599455

RESUMO

Strawberry has a limiting postharvest shelf life, especially because of soft rot. The antifungal activity of the essential oils (EOs) of Eucalyptus staigeriana, Lippia sidoides and Pimenta pseudocaryophyllus was tested in vitro against plant pathogen Rhizopus stolonifer. The chemical composition of the EO with the highest activity and its effects on pathogen morphology were verified. The in vivo antifungal activity of this EO associated with carboxymethylcellulose (CMC) coating, in preventive and curative applications, was also evaluated. L. sidoides EO presented the highest in vitro antifungal activity. The analysis of the chemical composition of this EO showed a prevalence of the compound thymol and the scanning and transmission electron microscopy showed that L. sidoides EO was able to cause damage to the cell wall and the intracellular components of the pathogen. Strawberries treated with L. sidoides EO associated with CMC presented a reduction in disease severity, especially when treated in a curative way.


Assuntos
Carboximetilcelulose Sódica/farmacologia , Fragaria/microbiologia , Fungicidas Industriais/farmacologia , Óleos Voláteis/farmacologia , Rhizopus/efeitos dos fármacos , Eucalyptus/química , Contaminação de Alimentos/prevenção & controle , Microbiologia de Alimentos , Lippia/química , Pimenta/química , Timol/farmacologia , Compostos Orgânicos Voláteis/farmacologia
15.
Phys Rev Lett ; 121(9): 093903, 2018 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-30230881

RESUMO

Continuously pumped passive nonlinear cavities can be harnessed for the creation of novel optical frequency combs. While most research has focused on third-order "Kerr" nonlinear interactions, recent studies have shown that frequency comb formation can also occur via second-order nonlinear effects. Here, we report on the formation of quadratic combs in optical parametric oscillator (OPO) configurations. Specifically, we demonstrate that optical frequency combs can be generated in the parametric region around half of the pump frequency in a continuously driven OPO. We also model the OPO dynamics through a single time-domain mean-field equation, identifying previously unknown dynamical regimes, induced by modulation instabilities, which lead to comb formation. Numerical simulation results are in good agreement with experimentally observed spectra. Moreover, the analysis of the coherence properties of the simulated spectra shows the existence of correlated and phase-locked combs. Our results reveal previously unnoticed dynamics of an apparently well assessed optical system, and can lead to a new class of frequency comb sources that may stimulate novel applications by enabling straightforward access to elusive spectral regions, such as the midinfrared.

16.
Lett Appl Microbiol ; 67(2): 168-174, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29740840

RESUMO

Plant proteases play a fundamental role in several processes like growth, development and in response to biotic and abiotic stress. In particular, aspartic proteases (AP) are expressed in different plant organs and have antimicrobial activity. Previously, we purified an AP from Salpichroa origanifolia fruits called salpichroin. The aim of this work was to determine the cytotoxic activity of this enzyme on selected plant and human pathogens. For this purpose, the growth of the selected pathogens was analysed after exposure to different concentrations of salpichroin. The results showed that the enzyme was capable of inhibiting Fusarium solani and Staphylococcus aureus in a dose-dependent manner. It was determined that 1·2 µmol l-1 of salpichroin was necessary to inhibit 50% of conidial germination, and the minimal bactericidal concentration was between 1·9 and 2·5 µmol l-1 . Using SYTOX Green dye we were able to demonstrate that salpichroin cause membrane permeabilization. Moreover, the enzyme treated with its specific inhibitor pepstatin A did not lose its antibacterial activity. This finding demonstrates that the cytotoxic activity of salpichroin is due to the alteration of the cell plasma membrane barrier but not due to its proteolytic activity. Antimicrobial activity of the AP could represent a potential alternative for the control of pathogens that affect humans or crops of economic interest. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides insights into the antimicrobial activity of an aspartic protease isolated from Salpichroa origanifolia fruits on plant and human pathogens. The proteinase inhibited Fusarium solani and Staphylococcus aureus in a dose-dependent manner due to the alteration of the cell plasma membrane barrier but not due to its proteolytic activity. Antimicrobial activity of salpichroin suggests its potential applications as an important tool for the control of pathogenic micro-organisms affecting humans and crops of economic interest. Therefore, it would represent a new alternative to avoid the problems of environmental pollution and antimicrobial resistance.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Ácido Aspártico Proteases/farmacologia , Fusarium/crescimento & desenvolvimento , Solanaceae/química , Staphylococcus aureus/crescimento & desenvolvimento , Antibacterianos/metabolismo , Antifúngicos/metabolismo , Ácido Aspártico Proteases/isolamento & purificação , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Frutas , Humanos , Testes de Sensibilidade Microbiana , Permeabilidade/efeitos dos fármacos
17.
Nature ; 555(7695): 223-226, 2018 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-29516995

RESUMO

The depth to which Jupiter's observed east-west jet streams extend has been a long-standing question. Resolving this puzzle has been a primary goal for the Juno spacecraft, which has been in orbit around the gas giant since July 2016. Juno's gravitational measurements have revealed that Jupiter's gravitational field is north-south asymmetric, which is a signature of the planet's atmospheric and interior flows. Here we report that the measured odd gravitational harmonics J3, J5, J7 and J9 indicate that the observed jet streams, as they appear at the cloud level, extend down to depths of thousands of kilometres beneath the cloud level, probably to the region of magnetic dissipation at a depth of about 3,000 kilometres. By inverting the measured gravity values into a wind field, we calculate the most likely vertical profile of the deep atmospheric and interior flow, and the latitudinal dependence of its depth. Furthermore, the even gravity harmonics J8 and J10 resulting from this flow profile also match the measurements, when taking into account the contribution of the interior structure. These results indicate that the mass of the dynamical atmosphere is about one per cent of Jupiter's total mass.

18.
Nature ; 555(7695): 227-230, 2018 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-29517000

RESUMO

Jupiter's atmosphere is rotating differentially, with zones and belts rotating at speeds that differ by up to 100 metres per second. Whether this is also true of the gas giant's interior has been unknown, limiting our ability to probe the structure and composition of the planet. The discovery by the Juno spacecraft that Jupiter's gravity field is north-south asymmetric and the determination of its non-zero odd gravitational harmonics J3, J5, J7 and J9 demonstrates that the observed zonal cloud flow must persist to a depth of about 3,000 kilometres from the cloud tops. Here we report an analysis of Jupiter's even gravitational harmonics J4, J6, J8 and J10 as observed by Juno and compared to the predictions of interior models. We find that the deep interior of the planet rotates nearly as a rigid body, with differential rotation decreasing by at least an order of magnitude compared to the atmosphere. Moreover, we find that the atmospheric zonal flow extends to more than 2,000 kilometres and to less than 3,500 kilometres, making it fully consistent with the constraints obtained independently from the odd gravitational harmonics. This depth corresponds to the point at which the electric conductivity becomes large and magnetic drag should suppress differential rotation. Given that electric conductivity is dependent on planetary mass, we expect the outer, differentially rotating region to be at least three times deeper in Saturn and to be shallower in massive giant planets and brown dwarfs.

19.
Nature ; 555(7695): 220-222, 2018 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-29517001

RESUMO

The gravity harmonics of a fluid, rotating planet can be decomposed into static components arising from solid-body rotation and dynamic components arising from flows. In the absence of internal dynamics, the gravity field is axially and hemispherically symmetric and is dominated by even zonal gravity harmonics J2n that are approximately proportional to qn, where q is the ratio between centrifugal acceleration and gravity at the planet's equator. Any asymmetry in the gravity field is attributed to differential rotation and deep atmospheric flows. The odd harmonics, J3, J5, J7, J9 and higher, are a measure of the depth of the winds in the different zones of the atmosphere. Here we report measurements of Jupiter's gravity harmonics (both even and odd) through precise Doppler tracking of the Juno spacecraft in its polar orbit around Jupiter. We find a north-south asymmetry, which is a signature of atmospheric and interior flows. Analysis of the harmonics, described in two accompanying papers, provides the vertical profile of the winds and precise constraints for the depth of Jupiter's dynamical atmosphere.

20.
J Endocrinol Invest ; 41(5): 567-573, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29064082

RESUMO

PURPOSE: Recent evidence indicates that people with normal glucose tolerance (NGT) but 1-h post-load plasma glucose (1-h OGTT) ≥ 155 mg/dl have an increased risk for developing Type 2 diabetes mellitus (T2DM), determining a new risk category with deeper metabolic impairment. The aim of this study was to identify, among women with gestational diabetes (GDM), which alterations at OGTT during pregnancy are more frequently associated with 1-h OGTT ≥ 155 mg/dl at post-partum examination. METHODS: Among 297 women affected by GDM, we retrospectively evaluated 244 resulted NGT after delivery. Based on post-partum glucose levels at 1-h OGTT, these people were divided into 188 cases (77.0%) with 1-h OGTT < 155 mg/dl (L-NGT) and 56 (23.0%) with 1-h OGTT ≥ 155 mg/dl (H-NGT). RESULTS: Abnormal glucose levels at 1-h OGTT during pregnancy (≥ 180 mg/dl) were more frequent in H-NGT than in L-NGT (39.3 vs. 24.6%, odds ratio 3.7 [95% CI 1.4-9.6]; p = 0.016). Moreover, H-NGT showed more frequently the simultaneous alteration of all three OGTT plasma glucose values during pregnancy (10.7 vs. 2.1%, odds ratio 4.5 [95% CI 1.5-20.3]; p = 0.038) and less frequently the alteration of fasting plasma glucose alone (14.3 vs. 30.8%, odds ratio 0.4 [95% CI 0.1-0.7]; p = 0.028). CONCLUSIONS: Abnormal 1-h OGTT during pregnancy predicts an increased risk for post-partum 1-h OGTT ≥ 155 mg/dl in women with previous GDM. Even if NGT after delivery, these women may require a closer long-term post-partum follow-up, being at higher risk to develop future glucose intolerance.


Assuntos
Diabetes Mellitus Tipo 2/etiologia , Diabetes Gestacional/fisiopatologia , Intolerância à Glucose/complicações , Hiperglicemia/complicações , Doenças Metabólicas/etiologia , Período Pós-Parto , Adulto , Biomarcadores/análise , Glicemia/análise , Feminino , Seguimentos , Teste de Tolerância a Glucose , Hemoglobinas Glicadas/análise , Humanos , Gravidez , Prognóstico , Estudos Retrospectivos
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