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BACKGROUND: After surgical resection of pancreatic ductal adenocarcinoma (PDAC), patients are predominantly treated with adjuvant chemotherapy, commonly consisting of gemcitabine (GEM)-based regimens or the modified FOLFIRINOX (mFFX) regimen. While mFFX regimen has been shown to be more effective than GEM-based regimens, it is also associated with higher toxicity. Current treatment decisions are based on patient performance status rather than on the molecular characteristics of the tumor. To address this gap, the goal of this study was to develop drug-specific transcriptomic signatures for personalized chemotherapy treatment. PATIENTS AND METHODS: We used PDAC datasets from preclinical models, encompassing chemotherapy response profiles for the mFFX regimen components. From them we identified specific gene transcripts associated with chemotherapy response. Three transcriptomic artificial intelligence signatures were obtained by combining independent component analysis and the least absolute shrinkage and selection operator-random forest approach. We integrated a previously developed GEM signature with three newly developed ones. The machine learning strategy employed to enhance these signatures incorporates transcriptomic features from the tumor microenvironment, leading to the development of the 'Pancreas-View' tool ultimately clinically validated in a cohort of 343 patients from the PRODIGE-24/CCTG PA6 trial. RESULTS: Patients who were predicted to be sensitive to the administered drugs (n = 164; 47.8%) had longer disease-free survival (DFS) than the other patients. The median DFS in the mFFX-sensitive group treated with mFFX was 50.0 months [stratified hazard ratio (HR) 0.31, 95% confidence interval (CI) 0.21-0.44, P < 0.001] and 33.7 months (stratified HR 0.40, 95% CI 0.17-0.59, P < 0.001) in the GEM-sensitive group when treated with GEM. Comparatively patients with signature predictions unmatched with the treatments (n = 86; 25.1%) or those resistant to all drugs (n = 93; 27.1%) had shorter DFS (10.6 and 10.8 months, respectively). CONCLUSIONS: This study presents a transcriptome-based tool that was developed using preclinical models and machine learning to accurately predict sensitivity to mFFX and GEM.
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With excellent energy resolution and ultralow-level radiogenic backgrounds, the high-purity germanium detectors in the Majorana Demonstrator enable searches for several classes of exotic dark matter (DM) models. In this work, we report new experimental limits on keV-scale sterile neutrino DM via the transition magnetic moment from conversion to active neutrinos ν_{s}âν_{a}. We report new limits on fermionic dark matter absorption (χ+Aâν+A) and sub-GeV DM-nucleus 3â2 scattering (χ+χ+AâÏ+A), and new exclusion limits for bosonic dark matter (axionlike particles and dark photons). These searches utilize the (1-100)-keV low-energy region of a 37.5-kg y exposure collected by the Demonstrator between May 2016 and November 2019 using a set of ^{76}Ge-enriched detectors whose surface exposure time was carefully controlled, resulting in extremely low levels of cosmogenic activation.
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Detecting the association of genetic variants to the response of biological therapy represents an important advance in developing a personalized therapy. The aim of this work was to study the association of polymorphisms with an optimal response to tildrakizumab in patients with psoriasis in a real-life clinical practice. Ninety patients with plaque psoriasis recruited from-Spanish hospitals receiving tildrakizumab for at least 24 weeks were genotyped for 180 polymorphisms. Optimal response to tildrakizumab was evaluated by absolute PASI ≤1 at 6 and 12 months. Polymorphisms corrected for weight and disease duration with an FDR <0.15 were included in a multiple regression model. Sixty three percent of patients achieved an absolute PASI ≤1 at 6 months, while 71% did so after 12 months. Disease duration (>27 years) and weight (>76 kg) were associated with treatment response; after correcting by these factors, no association (FDR >0.15) was found for any polymorphism and response to tildrakizumab at 6 months. The analysis at 12 months identified the genotype GG for rs610604 (TNFAIP3), CT for rs9373839 (ATG5), and delCTGT/delCTGT for rs72167053 (PDE4D) as risk factors to not achieve an optimal response (PASI ≤1), while CT for rs708567 (IL17RC) was protective, independently of weight and disease duration (FDR <0.15). The final multivariable model at 12 months showed an AUC of 0.90 (95% CI 0.82 to -0.98). We identified a set of polymorphisms that could be helpful to identify psoriatic patients with an optimal response to tildrakizumab at 12 months in real-world practice conditions.
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Anticorpos Monoclonais Humanizados , Psoríase , Humanos , Psoríase/tratamento farmacológico , Psoríase/genética , Feminino , Masculino , Pessoa de Meia-Idade , Anticorpos Monoclonais Humanizados/uso terapêutico , Adulto , Polimorfismo de Nucleotídeo Único , Resultado do Tratamento , Genótipo , Idoso , Polimorfismo GenéticoRESUMO
Bromine atom (Br) reactions lead to ozone depletion in the troposphere and stratosphere. Photodegradation of bromocarbons is one of the main sources of bromine atoms in the atmosphere. Here, we use high-level ab initio methods, including spin-orbit effects, to study the photodissociation of the CH2Br radical. All possible fragmentation pathways, namely CH2Br + hν â CH2 + Br, HCBr + H, and CBr + H2, have been analyzed. Potential-energy curves of the ground and several excited electronic states along the corresponding dissociating bond distance of each pathway have been calculated. Considering the actinic fluxes of solar irradiation in the troposphere and in the stratosphere in the relevant range of frequencies, it is found that the first five excited states of CH2Br can be accessed from the ground state. Analysis of the potential curves shows that the pathways producing CH2 + Br and HCBr + H can proceed through a fast direct dissociation mechanism, while the pathway leading to CBr + H2 involves much slower dissociation mechanisms like internal conversion between electronic states, predissociation, or tunneling through exit barriers. The main implications are that the two faster channels are predicted to be dominant, and the slower pathway is expected to be less relevant. The tropospheric and stratospheric solar actinic fluxes also allow for further dissociation of the HCBr and CBr fragments, generating additional Br atoms, provided that they survive possible collisions with other atmospheric reagents. Finally, we discuss the possible effect of each of the three CH2Br dissociation pathways on the depletion of atmospheric ozone.
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Parabens (PBs) are widely used in the cosmetic, pharmaceutical, and food industries as preservatives of products. Because of its great use, humans and other organisms are highly exposed daily. However, little is known about the effect of PBs on male infertility. Therefore, the aim of the present study was to evaluate the effect of methylparaben (MePB) and propylparaben (PrPB), alone or in combination, on the physiological characteristics of pig in vitro exposed sperm to different concentrations (0, 200, 500, and 700 µM) for viability, motility, and acrosome integrity evaluation and (0, 200, 500, 700, 1000, and 2000 µM) for DNA fragmentation index evaluation, after 4 h of exposure. The results showed that sperm viability decreased after exposure to MePB from the concentration of 500 µM. In the PrPB and mixture groups, viability decreased at all concentrations except for the control. The decrease in viability of sperm exposed to PrPB was greater than that of the mixture and MePB groups. Sperm motility decreased in all the experimental groups exposed to PBs, at all concentrations, except for the control group. Acrosome integrity was not decreased in the MePB group; however, in the PrPB group, it decreased at a concentration of 200 µM and in the mixture at 500 µM. All groups exhibited DNA damage at different concentrations, except for the control group. Additionally, the effect of PBs on sperm quality was concentration-dependent. The results demonstrated that MePB and PrPB alone or in combination can have adverse effects on sperm quality parameters. MePB had lower toxicity than did both PrPB and the mixture. The mixture did not have an additive effect on any of the parameters evaluated. This could partially explain the link between PB exposure and infertility.
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The preweaning period for a dairy calf is characterized by high morbidity and mortality rates, leading to financial losses for producers. Identifying strategies to improve the health and welfare of calves while reducing antimicrobial use continues to be crucial to the success of the dairy industry. The objective of this study was to determine the effects of feeding colostrum replacer (CR) to dairy heifer calves beyond d 1 of life on growth, serum IgG, the incidence of diarrhea and bovine respiratory disease (BRD), and the risk of mortality in the preweaning period. At birth, Holstein heifer calves (n = 200; 50/treatment) weighing 40.7 ± 0.35 kg (mean ± SE) were fed 3.2 L of CR (205 g IgG/feeding) at 0 h and 12 h of life. Calves were then randomly assigned to 1 of 4 treatments: 450 g of milk replacer (MR) from d 2 to 14 (control, CON), 380 g of CR + 225 g of MR from d 2 to 3, then 450 g of MR from d 4 to 14 (transition, TRAN), 45 g of CR + 450 g of MR from d 2 to 14 (extended, EXT); or 380 g of CR + 225 g of MR from d 2 to 3, then 45 g of CR + 450 g of MR from d 4 to 14 (transition + extended, TRAN+EXT). Each treatment was reconstituted to 3 L and fed twice daily. All CR treatments were fed using bovine-derived CR containing 27% IgG. From d 15 to 41, all calves were fed 600 g of MR reconstituted to 4 L twice daily. Body weight was recorded at birth and every 7 d until study completion on d 49. Blood samples were taken daily until d 7 to evaluate serum IgG and then every 7 d until d 49. A health assessment was performed daily to evaluate calves for BRD and diarrhea. Data were analyzed using mixed linear regression, mixed logistic regression, and survival analysis models in SAS 9.4. Serum IgG concentrations were not affected by treatment for the study period. The EXT and TRAN+EXT groups had greater average daily gain (ADG) from d 7 to 14 (0.14 kg/d) and the TRAN group had greater ADG from d 14 to 21 (0.11 kg/d), compared with CON. There was no association of treatment with the odds or the duration of a diarrhea bout. However, provision of CR to the TRAN and EXT calves was associated with a reduced hazard of diarrhea compared with CON calves. Furthermore, TRAN and EXT calves have a lower hazard of mortality compared with CON calves, with TRAN and EXT calves had a 2.8- and 3.8-times lower hazard of mortality, respectively. Our findings suggest that the supplementation of CR to dairy calves positively affects ADG, and reduces the hazard of diarrhea and mortality during the preweaning period. Future research should look to further refine the supplementation strategy of CR to calves and explore the mechanism of action.
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BACKGROUND AND OBJECTIVE: Burnout syndrome is a mental health disorder due to chronic occupational stress. Both burnout and associated comorbidities are prevalent among health care professionals, being medical residents a vulnerable group. Despite this, the scientific medical literature currently available on this issue in dermatology residents is scarce. The aim of this study was to analyze the prevalence of the burnout syndrome, anxiety, and depression in dermatology residents, and the associated risk factors. MATERIAL AND METHOD: This was a cross-sectional trial designed to include dermatology residents from Spain (from December 2022 through June 2023). A self-administered form was sent via online messaging applications, including validated scales to study professional quality of life, burnout syndrome, anxiety, and depression. RESULTS: A total of 48 dermatology residents were included in the study, 50% of whom (24/48) were women, with a mean age of 27 years (1.25). A total of 58.33% (28/48) of the residents had some degree of anxiety, 22.9% (11/48) some degree of depression, and 23.4% a moderate risk of burnout (11/48). Workload was the main risk factor associated with the 3 disorders studied, while managerial support or intrinsic motivation seem to play a protective role. CONCLUSIONS: Burnout syndrome and its comorbidities are both prevalent in dermatology residents in Spain and closely related to each other.
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BACKGROUND: The COVID-19 pandemic may have adversely affected the early diagnosis of skin cancer. OBJECTIVE: To compare epidemiological, clinical and histopathological characteristics in patients undergoing cutaneous squamous cell carcinoma (SCC) surgery before and after the beginning of the pandemic. MATERIAL & METHODS: We conducted a cross-sectional study including two case series: (1) patients operated on for SCC in the year after the first state of alarm in Spain (15 March 2020), and (2) patients with SCC operated on in the previous year. Epidemiological, clinical and histopathological variables, tumour stage and risk grade were collected. RESULTS: 248 patients were included (127 undergoing surgery before the pandemic and 121 after the pandemic). After the beginning of the pandemic, the percentage of high-risk SCC significantly increased from 35.3% to 46.2% (p=0.011). However, no significant differences were found in thickness, perineural invasion or metastases. CONCLUSIONS: Although there has not been a significant reduction in the number of SCC operated on after the pandemic, there has been a significant increase in high-risk SCC. All this could lead to an increase in skin cancer mortality in the future.
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COVID-19 , Carcinoma de Células Escamosas , Neoplasias Cutâneas , Humanos , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/cirurgia , Carcinoma de Células Escamosas/patologia , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/cirurgia , Neoplasias Cutâneas/patologia , Pandemias , COVID-19/epidemiologia , Estudos TransversaisRESUMO
BACKGROUND: The COVID-19 pandemic may have adversely affected the early diagnosis of skin cancer. OBJECTIVE: To compare epidemiological, clinical and histopathological characteristics in patients undergoing cutaneous squamous cell carcinoma (SCC) surgery before and after the beginning of the pandemic. MATERIAL & METHODS: We conducted a cross-sectional study including two case series: (1) patients operated on for SCC in the year after the first state of alarm in Spain (15 March 2020), and (2) patients with SCC operated on in the previous year. Epidemiological, clinical and histopathological variables, tumour stage and risk grade were collected. RESULTS: 248 patients were included (127 undergoing surgery before the pandemic and 121 after the pandemic). After the beginning of the pandemic, the percentage of high-risk SCC significantly increased from 35.3% to 46.2% (p=0.011). However, no significant differences were found in thickness, perineural invasion or metastases. CONCLUSIONS: Although there has not been a significant reduction in the number of SCC operated on after the pandemic, there has been a significant increase in high-risk SCC. All this could lead to an increase in skin cancer mortality in the future.
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COVID-19 , Carcinoma de Células Escamosas , Neoplasias Cutâneas , Humanos , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/cirurgia , Carcinoma de Células Escamosas/patologia , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/cirurgia , Neoplasias Cutâneas/patologia , Pandemias , COVID-19/epidemiologia , Estudos TransversaisRESUMO
BACKGROUND AND OBJECTIVE: Quality of professional life (QPL) is defined as a sense of well-being derived from a balance between the challenges of work and the resources available to deal with them. Impaired QPL can contribute to burnout. The aim of this study was to evaluate QPL in Spanish dermatologists using a validated questionnaire. MATERIAL AND METHODS: We designed a cross-sectional study in which Spanish dermatologists were invited to complete an online questionnaire sent out by messaging applications. The dermatologists were asked to provide sociodemographic information, answer 3 open questions, and complete the 35-item Spanish QPL questionnaire (Spanish abbreviation, CVP-35). RESULTS: We analyzed the information submitted by 106 dermatologists (62 women, 58%) with a mean age of 41 years (95% CI, 43.3-38.8 years). Women and department heads scored significantly higher in the workload domain of the questionnaire (P=.02 and P=.005, respectively). A heavy caseload was mentioned as the main factor contributing to impaired QPL and the main change in the wake of the COVID-19 pandemic. CONCLUSIONS: Female dermatologists reported heavier workloads. Heavy caseloads and more remote work were the main changes identified after the COVID-19 pandemic. Heavy caseloads have a significant impact on the QPL of dermatologists in Spain. Reducing caseloads would improve general job satisfaction and quality of care provision.
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Esgotamento Profissional , COVID-19 , Humanos , Feminino , Adulto , Dermatologistas , Estudos Transversais , Pandemias , COVID-19/epidemiologia , Satisfação no Emprego , Inquéritos e Questionários , Esgotamento Profissional/epidemiologiaRESUMO
The endocannabinoid system plays an important role in multiple behavioral responses due to its wide distribution in the central nervous system. The cannabinoid CB1 receptor was associated to the loss of behavioral control over food intake occurring during food addiction. The cannabinoid CB2 receptor (CB2R) is expressed in brain areas canonically associated with addictive-like behavior and was linked to drug-addictive properties. In this study, we evaluated for the first time the specific role of the CB2R in food addiction by using a well-validated operant mouse model of long-term training to obtain highly palatable food. We have compared in this model the behavioral responses of wild-type mice, mutant mice constitutively lacking CB2R, and transgenic mice overexpressing CB2R. The lack of CB2R constitutes a protective factor for the development of food addiction and the impulsive and depressive-like behavior associated. In contrast, the overexpression of CB2R induces a vulnerable phenotype toward food addiction after long-term exposure to highly palatable chocolate pellets. Relevant transcriptomic changes were associated to resilience and vulnerability to food addiction depending on the genotype, which provides a mechanistic explanation for these behavioral changes. Therefore, CB2R may constitute a potential therapeutic target for the loss of eating control and the comorbid emotional effects associated to food addiction.
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Canabinoides , Dependência de Alimentos , Camundongos , Masculino , Animais , Receptor CB2 de Canabinoide/genética , Encéfalo , Endocanabinoides , Receptor CB1 de Canabinoide/genéticaRESUMO
Spatial coherence of light sources is usually obtained by using the classical Young's interferometer. Although the original experiment was improved upon in successive works, some drawbacks still remain. For example, several pairs of points must be used to obtain the complex coherence degree (normalized first-order correlation function) of the source. In this work, a modified Mach-Zehnder interferometer which includes a pair of lenses and is able to measure the spatial coherence degree is presented. With this modified Mach-Zehnder interferometer, it is possible to measure the full 4D spatial coherence function by displacing the incoming beam laterally. To test it, we have measured only a 2D projection (zero shear) of the 4D spatial coherence, which is enough to characterize some types of sources. The setup has no movable parts, making it robust and portable. To test it, the two-dimensional spatial coherence of a high-speed laser with two cavities was measured for different pulse energy values. We observe from the experimental measurements that the complex degree of coherence changes with the selected output energy. Both laser cavities seem to have similar complex coherence degrees for the maximum energy, although it is not symmetrical. Thus, this analysis will allow us to determine the best configuration of the double-cavity laser for interferometric applications. Furthermore, the proposed approach can be applied to any other light sources.
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Lasers , Lentes , Interferometria/métodosRESUMO
The Majorana Demonstrator searched for neutrinoless double-ß decay (0νßß) of ^{76}Ge using modular arrays of high-purity Ge detectors operated in vacuum cryostats in a low-background shield. The arrays operated with up to 40.4 kg of detectors (27.2 kg enriched to â¼88% in ^{76}Ge). From these measurements, the Demonstrator has accumulated 64.5 kg yr of enriched active exposure. With a world-leading energy resolution of 2.52 keV FWHM at the 2039 keV Q_{ßß} (0.12%), we set a half-life limit of 0νßß in ^{76}Ge at T_{1/2}>8.3×10^{25} yr (90% C.L.). This provides a range of upper limits on m_{ßß} of (113-269) meV (90% C.L.), depending on the choice of nuclear matrix elements.
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This corrects the article DOI: 10.1103/PhysRevLett.129.080401.
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Nowadays, consumers are increasingly aware of the relationship between diet and health, showing a greater preference of products from natural origin. In the last decade, seaweeds have outlined as one of the natural sources with more potential to obtain bioactive carbohydrates. Numerous seaweed polysaccharides have aroused the interest of the scientific community, due to their biological activities and their high potential on biomedical, functional food and technological applications. To obtain polysaccharides from seaweeds, it is necessary to find methodologies that improve both yield and quality and that they are profitable. Nowadays, environmentally friendly extraction technologies are a viable alternative to conventional methods for obtaining these products, providing several advantages like reduced number of solvents, energy and time. On the other hand, chemical modification of their structure is a useful approach to improve their solubility and biological properties, and thus enhance the extent of their potential applications since some uses of polysaccharides are still limited. The present review aimed to compile current information about the most relevant seaweed polysaccharides, available extraction and modification methods, as well as a summary of their biological activities, to evaluate knowledge gaps and future trends for the industrial applications of these compounds.Key teaching pointsStructure and biological functions of main seaweed polysaccharides.Emerging extraction methods for sulfate polysaccharides.Chemical modification of seaweeds polysaccharides.Potential industrial applications of seaweed polysaccharides.Biological activities, knowledge gaps and future trends of seaweed polysaccharides.
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Produtos Biológicos , Polissacarídeos , Alga Marinha , Alga Marinha/química , Polissacarídeos/análise , Polissacarídeos/química , Alimento Funcional , Alginatos/análise , Alginatos/química , Ágar/análise , Ágar/química , Carragenina/análise , Carragenina/química , Fracionamento Químico/métodos , Estrutura MolecularRESUMO
BACKGROUND AND AIMS: Grasses of the Festuca genus have complex phylogenetic relations due to morphological similarities among species and interspecific hybridization processes. Within Patagonian fescues, information concerning phylogenetic relationships is very scarce. In Festuca pallescens, a widely distributed species, the high phenotypic variability and the occurrence of interspecific hybridization preclude a clear identification of the populations. Given the relevance of natural rangelands for livestock production and their high degradation due to climate change, conservation actions are needed and knowledge about genetic variation is required. METHODS: To unravel the intraspecific phylogenetic relations and to detect genetic differences, we studied 21 populations of the species along its natural geographical distribution by coupling both molecular [internal transcribed spacer (ITS) and trnL-F markers] and morpho-anatomical analyses. Bayesian inference, maximum likelihood and maximum parsimony methods were applied to assemble a phylogenetic tree, including other native species. The morphological data set was analysed by discriminant and cluster analyses. KEY RESULTS: The combined information of the Bayesian tree (ITS marker), the geographical distribution of haplotype variants (trnL-F marker) and the morpho-anatomical traits, distinguished populations located at the margins of the distribution. Some of the variants detected were shared with other sympatric species of fescues. CONCLUSIONS: These results suggest the occurrence of hybridization processes between species of the genus at peripheral sites characterized by suboptimal conditions, which might be key to the survival of these populations.
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Festuca , Filogenia , Festuca/genética , Teorema de Bayes , Variação Genética , Poaceae/genética , Análise de Sequência de DNARESUMO
BACKGROUND: Patients undergoing mechanical ventilation (MV) for COVID-19 exhibit an increased risk of ventilator-associated pneumonia (VAP). The occurrence of lung abscesses following VAP in these patients has been poorly studied. We aimed to describe the incidence, characteristics, risk factors and prognosis of lung abscesses complicating VAP after COVID-19. METHODS: We conducted an observational, retrospective study in three French intensive care units. Patients admitted for acute respiratory failure with a confirmed SARS-CoV-2 PCR and requiring MV for more than 48 h were included. RESULTS: Among the 507 patients included, 326 (64%) had a documented VAP. Of these, 23 (7%) developed a lung abscess. Enterobacterales (15/23, 65%) were the main documentation, followed by non-fermenting Gram-negative bacilli (10/23, 43%) and Gram-positive cocci (8/23, 35%). Lung abscesses were mainly plurimicrobial (15/23, 65%). In multivariate analysis, a plurimicrobial 1st VAP episode (OR (95% CI) 2.93 (1.16-7.51); p = 0.02) and the use of hydrocortisone (OR (95% CI) 4.86 (1.95-12.1); p = 0.001) were associated with lung abscess development. Intensive care unit (ICU) mortality of patients with lung abscesses reached 52%, but was not significantly higher than for patients with VAP but no lung abscess. Patients with lung abscesses had reduced ventilator-free days at day 60, a longer duration of MV and ICU stay than patients with VAP but no lung abscess (respectively, 0 (0-3) vs. 16 (0-42) days; p < 0.001, 49 (32-73) vs. 25 (11-41) days; p < 0.001, 52 (36-77) vs. 28 (16-47) days; p < 0.001). CONCLUSIONS: Lung abscessing pneumonia is not uncommon among COVID-19 patients developing VAP. A plurimicrobial first VAP episode and the use of hydrocortisone are independently associated with this complication. In COVID-19 patients with persistent VAP, a chest CT scan investigating the evolution toward lung abscess should be considered.
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COVID-19 , Abscesso Pulmonar , Pneumonia Associada à Ventilação Mecânica , Humanos , Pneumonia Associada à Ventilação Mecânica/epidemiologia , Pneumonia Associada à Ventilação Mecânica/etiologia , Abscesso Pulmonar/complicações , Estudos Retrospectivos , Estudos de Coortes , Hidrocortisona , COVID-19/complicações , SARS-CoV-2 , Respiração Artificial/efeitos adversos , Unidades de Terapia IntensivaRESUMO
Fe-doped carbon xerogels with a highly developed graphitic structure were synthesized by a one-step sol-gel polymerization. These highly graphitic Fe-doped carbons are presented as promising dual-functional electro-Fenton catalysts to perform both the electro-reduction of O2 to H2O2 and H2O2 catalytic decomposition (Fenton) for wastewater decontamination. The amount of Fe is key to the development of this electrode material, since affects the textural properties; catalyzes the development of graphitic clusters improving the electrode conductivity; and influences the O2-catalyst interaction controlling the H2O2 selectivity but, at the same time is the catalyst for the decomposition of the electrogenerated H2O2 to OH⢠radicals for the organic pollutants oxidation. All materials achieve the development of ORR via the 2-electron route. The presence of Fe considerably improves the electro-catalytic activity. However, a mechanism change seems to occur at around -0.5 V in highly Fe-doped samples. At potential lower than -0.5 eV, the present of Feδ+ species or even Fe-O-C active sites favour the selectivity to 2e-pathway, however at higher potentials, Feδ+ species are reduced favoring a O-O strong interaction enhancing the 4e-pathway. The Electro-Fenton degradation of tetracycline was analyzed. The TTC degradation is almost complete (95.13%) after 7 h of reaction without using any external Fenton-catalysts.
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Grafite , Poluentes Químicos da Água , Carbono , Águas Residuárias , Peróxido de Hidrogênio/química , Poluentes Químicos da Água/análise , Tetraciclina , Antibacterianos , OxirreduçãoRESUMO
During the East Antarctic International Ice Sheet Traverse (Eaiist, december 2019), in an unexplored part of the East Antarctic Plateau, snow samples were collected to expand our knowledge of the latitudinal variability of iodine, bromine and sodium as well as their relation in connection with emission processes and photochemical activation in this unexplored area. A total of 32 surface (0-5 cm) and 32 bulk (average of 1 m depth) samples were taken and analysed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Our results show that there is no relevant latitudinal trend for bromine and sodium. For bromine they also show that it has no significant post-depositional mechanisms while its inland surface snow concentration is influenced by spring coastal bromine explosions. Iodine concentrations are several orders of magnitude lower than bromine and sodium and they show a decreasing trend in the surface samples concentration moving southward. This suggests that other processes affect its accumulation in surface snow, probably related to the radial reduction in the ozone layer moving towards central Antarctica. Even though all iodine, bromine and sodium present similar long-range transport from the dominant coastal Antarctic sources, the annual seasonal cycle of the ozone hole over Antarctica increases the amount of UV radiation (in the 280-320 nm range) reaching the surface, thereby affecting the surface snow photoactivation of iodine. A comparison between the bulk and surface samples supports the conclusion that iodine undergoes spring and summer snow recycling that increases its atmospheric lifetime, while it tends to accumulate during the winter months when photochemistry ceases.
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Iodo , Bromo , Neve , Sódio , Regiões AntárticasRESUMO
BACKGROUND: Impairment of smell is more commonly related to chronic rhinosinusitis with nasal polyps (CRSwNP) than without, especially when asthma and/or NSAID-exacerbated respiratory disease and type 2 inflammation are also present. Therapeutic options include intranasal and systemic corticosteroids, surgery, and, more recently, biological therapy. We summarize current knowledge on the effect of biologics on olfaction in patients with CRSwNP. METHODS: We performed a systematic search of the PubMed and Cochrane databases from January 2001 to June 2022. The inclusion criteria were as follows: adult patients with CRS treated with dupilumab, omalizumab, mepolizumab, benralizumab, or reslizumab; and studies published in English reporting outcomes for sense of smell based on psychophysical and/or subjective tools. We excluded reports that did not assess CRSwNP, loss of smell evaluated with a method other than those accepted in the inclusion criteria, review articles, and expert opinions. No funding was received. RESULTS: Dupilumab has demonstrated rapid and sustained long-term improvement in smell in clinical trials and in real life. Omalizumab improves smell at 24 weeks. This improvement is maintained in the long-term, although it is not clinically relevant. Mepolizumab and benralizumab improved smell in the long term based on a subjective scale. No studies examining the improvement in smell in patients with CRSwNP treated with reslizumab were found. Indirect comparisons by meta-analysis consistently conclude that dupilumab is the most effective biologic for improving impaired sense of smell. CONCLUSION: Dupilumab seems to be more efficacious for improving the sense of smell than omalizumab, mepolizumab, and benralizumab.