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1.
Nature ; 600(7890): 621-624, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34937892

RESUMO

Magnetars are strongly magnetized, isolated neutron stars1-3 with magnetic fields up to around 1015 gauss, luminosities of approximately 1031-1036 ergs per second and rotation periods of about 0.3-12.0 s. Very energetic giant flares from galactic magnetars (peak luminosities of 1044-1047 ergs per second, lasting approximately 0.1 s) have been detected in hard X-rays and soft γ-rays4, and only one has been detected from outside our galaxy5. During such giant flares, quasi-periodic oscillations (QPOs) with low (less than 150 hertz) and high (greater than 500 hertz) frequencies have been observed6-9, but their statistical significance has been questioned10. High-frequency QPOs have been seen only during the tail phase of the flare9. Here we report the observation of two broad QPOs at approximately 2,132 hertz and 4,250 hertz in the main peak of a giant γ-ray flare11 in the direction of the NGC 253 galaxy12-17, disappearing after 3.5 milliseconds. The flare was detected on 15 April 2020 by the Atmosphere-Space Interactions Monitor instrument18,19 aboard the International Space Station, which was the only instrument that recorded the main burst phase (0.8-3.2 milliseconds) in the full energy range (50 × 103 to 40 × 106 electronvolts) without suffering from saturation effects such as deadtime and pile-up. Along with sudden spectral variations, these extremely high-frequency oscillations in the burst peak are a crucial component that will aid our understanding of magnetar giant flares.


Assuntos
Astros Celestes , Atmosfera
2.
Ann Hematol ; 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38884787

RESUMO

FLT3-ITD and NPM1 mutations are key to defining the genetic risk profile of acute myeloid leukemia (AML). We aimed to assess the prognostic features of the FLT3-ITD and NPM1 mutations in old and/or unfit individuals with AML treated with non-intensive therapies in the era before azacitidine-venetoclax approbation. The results of various non-intensive regimens were also compared. We conducted a retrospective analysis that included patients treated with different non-intensive regimens, between 2007 and 2020 from PETHEMA AML registry. We compiled 707 patients with a median age of 74 years and median follow-up time of 37.7 months. FLT3-ITD patients (N = 98) showed a non-significant difference in overall survival (OS) compared to FLT3-ITD negative-patients (N = 608) (P = 0.17, median OS was 5 vs 7.3 months respectively). NPM1-mutated patients (N = 144) also showed a non-significant difference with NPM1 wild type (N = 519) patients (P = 0.25, median OS 7.2 vs 6.8 respectively). In the Cox regression analysis neither NPM1 nor FLT3-ITD nor age were significant prognostic variables for OS prediction. Abnormal karyotype and a high leukocyte count showed a statistically significant deleterious effect. Azacitidine also showed better survival compared to FLUGA (low dose cytarabine plus fludarabine). NPM1 and FLT3-ITD seem to lack prognostic value in older/unfit AML patients treated with non-intensive regimens other than azacitidine-venetoclax combination.

3.
Emerg Infect Dis ; 28(3): 548-555, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35081022

RESUMO

To assess whether high-dose coronavirus disease (COVID-19) convalescent plasma (CCP) transfusion may benefit patients with severe COVID-19, we conducted a multicenter randomized trial in Brazil. Patients with severe COVID-19 who were within 10 days of initial symptom onset were eligible. Patients in the CCP group received 3 daily doses of CCP (600 mL/d) in addition to standard treatment; control patients received standard treatment only. Primary outcomes were death rates at days 30 and 60 of study randomization. Secondary outcomes were ventilator-free days and hospital-free days. We enrolled 107 patients: 36 CCP and 71 control. At day 30, death rates were 22% for CCP and 25% for the control group; at day 60, rates were 31% for CCP and 35% for control. Needs for invasive mechanical ventilation and durations of hospital stay were similar between groups. We conclude that high-dose CCP transfused within 10 days of symptom onset provided no benefit for patients with severe COVID-19.


Assuntos
COVID-19 , COVID-19/terapia , Humanos , Imunização Passiva/efeitos adversos , Plasma , SARS-CoV-2 , Resultado do Tratamento , Soroterapia para COVID-19
4.
Mol Hum Reprod ; 28(11)2022 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-36205711

RESUMO

COVID-19 exerts systemic effects that can compromise various organs and systems. Although retrospective and in silico studies and prospective preliminary analysis have assessed the possibility of direct infection of the endometrium, there is a lack of in-depth and prospective studies on the impact of systemic disease on key endometrial genes and functions across the menstrual cycle and window of implantation. Gene expression data have been obtained from (i) healthy secretory endometrium collected from 42 women without endometrial pathologies and (ii) nasopharyngeal swabs from 231 women with COVID-19 and 30 negative controls. To predict how COVID-19-related gene expression changes impact key endometrial genes and functions, an in silico model was developed by integrating the endometrial and COVID-19 datasets in an affected mid-secretory endometrium gene co-expression network. An endometrial validation set comprising 16 women (8 confirmed to have COVID-19 and 8 negative test controls) was prospectively collected to validate the expression of key genes. We predicted that five genes important for embryo implantation were affected by COVID-19 (downregulation of COBL, GPX3 and SOCS3, and upregulation of DOCK2 and SLC2A3). We experimentally validated these genes in COVID-19 patients using endometrial biopsies during the secretory phase of the menstrual cycle. The results generally support the in silico model predictions, suggesting that the transcriptomic landscape changes mediated by COVID-19 affect endometrial receptivity genes and key processes necessary for fertility, such as immune system function, protection against oxidative damage and development vital for embryo implantation and early development.


Assuntos
COVID-19 , Humanos , Feminino , Estudos Prospectivos , COVID-19/genética , Estudos Retrospectivos , Endométrio/metabolismo , Implantação do Embrião/genética
5.
Transfus Med ; 32(3): 248-251, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34085363

RESUMO

OBJECTIVES: Evaluate the impact of ABO histo-blood group type on COVID-19 severity. BACKGROUND: ABO histo-blood type has been associated with different outcomes in infectious diseases. It has also shown a higher proportion of type A patients with SARS-CoV-2. In this observational study, extracted from an ongoing clinical trial on the efficacy of convalescent plasma transfused in COVID-19 patients, we describe the impact of ABO blood type on the risk of developing severe COVID-19. MATERIALS AND METHODS: Seventy-two consecutive patients (37 type A, 23 type O, 11 type B, 1 type AB) with severe (respiratory failure) COVID-19 were included. Control group was composed of 160 individuals randomly selected from the same populational basis. RESULTS: Blood group A was overrepresented (51.39%) in the patient group in relation to the control group (30%), whereas blood group O was less represented (31.94%) in patient than in control group (48%). Odds ratio (A vs. O) was 2.581 (1.381-4.817), CI 95%; p = 0.004. Also, blood group A patients appeared to have more severe disease, given by the scores of the Sequential Organ Failure Assessment and Simplified Acute Physiologic Score 3 (p = 0.036 and p = 0.058, respectively). CONCLUSION: Histo-blood type A is associated with a higher risk of developing severe COVID-19 in relation to blood type O.


Assuntos
COVID-19 , Sistema ABO de Grupos Sanguíneos , COVID-19/terapia , Humanos , Imunização Passiva , Fatores de Risco , SARS-CoV-2 , Soroterapia para COVID-19
6.
Transfusion ; 60(9): 2139-2143, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32735379

RESUMO

CASE REPORT: A 26-year-old woman with sickle cell disease (SCD) on chronic transfusion therapy complained of severe arthralgia, myalgia, abdominal pain, headache, and fever 24 hours after transfusion of a red blood cells (RBCs). Dengue virus (DENV) infection was suspected and the patient was hospitalized for clinical support and RBC transfusion, to lower the hemoglobin S to less than 30%. The patient's clinical condition improved approximately 8 days after the onset of symptoms. RESULTS: DENV type 2 (DENV-2) TaqMan real-time polymerase chain reaction was negative in the patient's pretransfusion sample while the posttransfusion sample was positive (Ct, 27.8), suggesting a high viral load and an acute infection. To investigate DENV transfusion transmission (TT-DENV) the stored donor serum was tested and was also positive (Ct, 25.8). Molecular typing confirmed the presence of DENV-2. The phylogenetic analysis of the DENV-2 strains obtained from both donor and patient samples were classified as the Southeast Asia-American genotype (Genotype III) and demonstrated 100% genomic identity, indicating TT-DENV. CONCLUSION: This is the first description of TT-DENV in a SCD patient. A presumed high viral load in the transfused RBC unit probably determined the early clinical manifestation. In endemic regions dengue fever should be considered as differential diagnosis in SCD patients with fever and acute pain crisis, mainly during DENV outbreaks.


Assuntos
Anemia Falciforme , Vírus da Dengue , Dengue , Transfusão de Eritrócitos/efeitos adversos , Vasoconstrição , Adulto , Anemia Falciforme/sangue , Anemia Falciforme/fisiopatologia , Anemia Falciforme/terapia , Dengue/sangue , Dengue/etiologia , Dengue/fisiopatologia , Feminino , Humanos , Reação Transfusional/sangue , Reação Transfusional/fisiopatologia
7.
J Phys Chem A ; 123(36): 7792-7802, 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31429287

RESUMO

Electron transfer coupling is a critical factor in determining electron transfer rates. This coupling strength can be sensitive to details in molecular geometries, especially intermolecular configurations. Thus, studying charge transporting behavior with a full first-principle approach demands a large amount of computation resources in quantum chemistry (QC) calculation. To address this issue, we developed a machine learning (ML) approach to evaluate electronic coupling. A prototypical ML model for an ethylene system was built by kernel ridge regression with Coulomb matrix representation. Since the performance of the ML models highly dependent on their building strategies, we systematically investigated the generality of the ML models, the choice of features and target labels. The best ML model trained with 40 000 samples achieved a mean absolute error of 3.5 meV and greater than 98% accuracy in predicting phases. The distance and orientation dependence of electronic coupling was successfully captured. Bypassing QC calculation, the ML model saved 10-104 times the computation cost. With the help of ML, reliable charge transport models and mechanisms can be further developed.

8.
Br J Surg ; 105(4): 439-446, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29488646

RESUMO

BACKGROUND: Pancreatic mucinous cystic neoplasms (MCNs) are rare mucin-producing cystic tumours defined by the presence of ovarian-type stroma. MCNs have a malignant potential and thus surgery is frequently performed. The aim of this cohort study was to define better the criteria for surgical resection in patients with MCN. METHODS: This multicentre retrospective study included all resected MCNs between 2003 and 2015 in participating centres. Lesions without ovarian-type stroma were excluded. Patient characteristics, preoperative findings, histopathology findings and follow-up data were recorded. RESULTS: The study included 211 patients; their median age was 53 (range 18-82) years, and 202 (95·7 per cent) were women. Median preoperative tumour size was 55 (range 12-230) mm. Thirty-four of the 211 (16·1 per cent) were malignant, and high-grade dysplasia (HGD) was found in a further 13 (6·2 per cent). One-third of MCNs in men were associated with invasive cancer, compared with 15·3 per cent in women. Five cases of malignant transformation occurred in MCNs smaller than 4 cm. All cases of malignancy or HGD were associated with symptoms or features of concern on preoperative cross-sectional imaging. In multivariable analysis, raised carbohydrate antigen 19-9 (odds ratio (OR) 10·54, 95 per cent c.i. 2·85 to 218·23; P < 0·001), tumour size (OR 4·23, 3·02 to 11·03; P = 0·001), mural nodules (OR 3·55, 1·31 to 20·55; P = 0·002) and weight loss (OR 3·40, 2·34 to 12·34; P = 0·034) were independent factors predictive of malignant transformation. CONCLUSIONS: Small indeterminate MCNs with no symptoms or features of concern may safely be observed as they have a low risk of malignant transformation.


Assuntos
Cistadenocarcinoma Mucinoso/patologia , Cistadenocarcinoma Mucinoso/cirurgia , Pancreatectomia , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Risco , Adulto Jovem
9.
HNO ; 66(7): 534-542, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29876624

RESUMO

Eosinophilic esophagitis (EoE) is a recently recognised pathologic entity whose prevalence has risen significantly since first being described in 1993. Defined as a chronic, local immune-mediated disease with predominant eosinophil infiltration, it is nowadays the leading cause of dysphagia and food bolus impaction in children and young adults. Genetic and environmental risk factors, and especially food antigens, trigger the disease and are in the focus of investigation as avoidance can cure three quarters of patients. The most common antigen involved is milk, followed by egg and gluten. These patients frequently come undiagnosed to the otolaryngologist with complaints of dysphagia and recurrent non-sharp food impactions, although pharyngolaryngeal reflux symptoms and other airway complaints could also be a first sign. Delayed diagnosis and treatment can produce fibrostenosis of the esophagus that greatly impairs patients' quality of life.In-office transnasal esophagoscopy with esophageal biopsy offers a unique opportunity to promptly diagnose and follow-up these patients, without causing the morbidity of repeated sedations and reducing exploration overload in gastroenterology departments. The search for food-antigen triggers, response evaluation to swallowed steroids, or proton pump inhibitors (PPIs) make multiple endoscopies and biopsies necessary every 6 to 8 weeks.There are three first-line interchangeable treatments with the same recommendation: PPIs, dietary allergen elimination and topical swallowed steroids. The choice should be discussed with the patient on an individual basis.The objective of this article is to raise awareness of this condition, update otolaryngologists with the new EoE consensus, and highlight the need for biopsy in patients with dysphagia to rule out EoE.


Assuntos
Transtornos de Deglutição , Esofagite Eosinofílica , Adolescente , Criança , Pré-Escolar , Esofagite Eosinofílica/complicações , Esofagite Eosinofílica/diagnóstico , Esofagoscopia , Humanos , Lactente , Otorrinolaringologistas , Qualidade de Vida , Adulto Jovem
13.
Enferm Intensiva ; 26(2): 72-81, 2015.
Artigo em Espanhol | MEDLINE | ID: mdl-25882964

RESUMO

OBJECTIVE: To evaluate and assess the nursing workload (NW) scales by means of three scales and to determine the theoretical and real nurse/patient relationship in a polyvalent ICU. METHODOLOGY: Cross-sectional descriptive study between July 2012 and June 2013 in patients over 18 years old, for which 3 nurses quantified, in randomized days, the NW by the Nursing Activities Score (NAS), Nine Equivalents Manpower Score (NEMS) and Valoración de Cargas de Trabajo y Tiempos de Enfermería (VACTE). Efficiency parameters of nursing resources were calculated: "work utilization ratio" (WUR), "level of care" operative (LOCop) and planned (LOCp). Data on demographics, length of stay and number of nurses were collected. RESULTS: 720 records were collected. The mean age was 64 (13.6) years. 73% were male and the median of length of stay was 3 (1-12) days. 60% were admitted for medical causes. The average total score was: NAS: 696.8 (111.6), NEMS: 311.8 (55.3) and VACTE: 4,978 (897.7). The required number of nurses according to NAS was 7 and 6,7 according to NEMS and VACTE. The actual average was 5.5. On all 3 scales the WUR was >1 and LOCop was 1.6 pacients/nurse. The LOCp was 2 patients/nurse. CONCLUSION: Assessing NW allows to know the reality of each unit. According to the scales and efficiency parameters of the nursing resources used, there is a shortage of nurses in relation to the work generated. NAS reflects more parameters of NW.


Assuntos
Recursos em Saúde/estatística & dados numéricos , Unidades de Terapia Intensiva , Enfermagem , Carga de Trabalho/estatística & dados numéricos , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
15.
Cell Mol Life Sci ; 70(18): 3449-62, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23661015

RESUMO

During the development of the central nervous system (CNS), oligodendrocyte precursors (OPCs) are generated in specific sites within the neural tube and then migrate to colonize the entire CNS, where they differentiate into myelin-forming oligodendrocytes. Demyelinating diseases such as multiple sclerosis (MS) are characterized by the death of these cells. The CNS reacts to demyelination and by promoting spontaneous remyelination, an effect mediated by endogenous OPCs, cells that represent approximately 5-7 % of the cells in the adult brain. Numerous factors influence oligodendrogliogenesis and oligodendrocyte differentiation, including morphogens, growth factors, chemotropic molecules, extracellular matrix proteins, and intracellular cAMP levels. Here, we show that during development and in early adulthood, OPCs in the murine cerebral cortex contain phosphodiesterase-7 (PDE7) that metabolizes cAMP. We investigated the effects of different PDE7 inhibitors (the well-known BRL-50481 and two new ones, TC3.6 and VP1.15) on OPC proliferation, survival, and differentiation. While none of the PDE7 inhibitors analyzed altered OPC proliferation, TC3.6 and VP1.15 enhanced OPC survival and differentiation, processes in which ERK intracellular signaling played a key role. PDE7 expression was also observed in OPCs isolated from adult human brains and the differentiation of these OPCs into more mature oligodendroglial phenotypes was accelerated by treatment with both new PDE7 inhibitors. These findings reveal new roles for PDE7 in regulating OPC survival and differentiation during brain development and in adulthood, and they may further our understanding of myelination and facilitate the development of therapeutic remyelination strategies for the treatment of MS.


Assuntos
Córtex Cerebral/enzimologia , Nucleotídeo Cíclico Fosfodiesterase do Tipo 7/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Oligodendroglia/efeitos dos fármacos , Adulto , Animais , Diferenciação Celular , Proliferação de Células , Sobrevivência Celular , Sistema Nervoso Central/metabolismo , AMP Cíclico/metabolismo , Epilepsia/metabolismo , Humanos , Camundongos , Microscopia de Fluorescência , Pessoa de Meia-Idade , Esclerose Múltipla/metabolismo , Oligodendroglia/citologia , Fenótipo , Transdução de Sinais
16.
J Med Pract Manage ; 30(1): 24-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25241445

RESUMO

The field of medical billing and collections continues to evolve along with current developments in U.S. healthcare reform. Although there has been a significant shift of payment responsibility from third-party payers to patients, many practices are not equipped to handle this change. As patients' financial obligations increase, the physician's ability to collect from patients will become increasingly important. Inability to collect bills receivable can adversely affect the revenue cycle of the practice. Solutions include improvement of the point-of-service collection processes, properly trained office staff, written financial policies, and the use of technology to facilitate online payments. Patients should fully understand their financial responsibilities and options available to them for payment of services rendered.


Assuntos
Crédito e Cobrança de Pacientes , Satisfação do Paciente , Administração da Prática Médica/economia , Humanos , Estados Unidos
17.
Microbiol Resour Announc ; : e0005924, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38967490

RESUMO

We report a metaproteomic analysis of the gut microbiota of eight infants with cystic fibrosis, during the first year of life. This is the first study in this disease that uses metaproteomics to analyze stool samples from patients at such a young age.

18.
Arch Soc Esp Oftalmol (Engl Ed) ; 99(1): 23-32, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37661041

RESUMO

The treatment of dark circles is one of the most common request from the patients attending to the esthetics clinic. A tired, sad or aged appearance is perceived by our patients. Moreover, it is a multifactorial problem and we could treat it with a wide range of treatments. With this systematic review, we want to check the best available evidence regarding the treatment of periorbital hyperpigmentation using light devices. We have reviewed 208 papers, including 14 of them for full consideration. Several light sources have demonstrated to be effective treating pigmented dark circles. The best results have been reported using intense pulsed light and rubi laser together with depigmenting substances. If we want to treat periocular hyperpigmentation, soft wrinkles, rhytides and skin density we should use carbo dioxide laser or Erbium:Yttrium Scandium Gallium Garnet. The Neodymium-Doped Yttrium Aluminium Garnet, alexandrite and diode lasers were the ones giving the worst outcome regarding pigmentation treatment. The concomitant use of depigmenting treatment may help getting better results and reducing the rate of post inflammatory hyperpigmentation. A better standardization and measuring of the obtained results is needed regarding pigmentation changes. We must keep on investigating on this topic with new clinical trials measuring objective results and combining different light devices for a multifactorial treatment of the dark circles.


Assuntos
Hiperpigmentação , Envelhecimento da Pele , Humanos , Idoso , Hiperpigmentação/etiologia , Hiperpigmentação/terapia , Pele , Resultado do Tratamento , Ítrio
19.
J Proteome Res ; 12(1): 112-22, 2013 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-23234512

RESUMO

The Chromosome 16 Consortium forms part of the Human Proteome Project that aims to develop an entire map of the proteins encoded by the human genome following a chromosome-centric strategy (C-HPP) to make progress in the understanding of human biology in health and disease (B/D-HPP). A Spanish consortium of 16 laboratories was organized into five working groups: Protein/Antibody microarrays, protein expression and Peptide Standard, S/MRM, Protein Sequencing, Bioinformatics and Clinical healthcare, and Biobanking. The project is conceived on a multicenter configuration, assuming the standards and integration procedures already available in ProteoRed-ISCIII, which is encompassed within HUPO initiatives. The products of the 870 protein coding genes in chromosome 16 were analyzed in Jurkat T lymphocyte cells, MCF-7 epithelial cells, and the CCD18 fibroblast cell line as it is theoretically expected that most chromosome 16 protein coding genes are expressed in at least one of these. The transcriptome and proteome of these cell lines was studied using gene expression microarray and shotgun proteomics approaches, indicating an ample coverage of chromosome 16. With regard to the B/D section, the main research areas have been adopted and a biobanking initiative has been designed to optimize methods for sample collection, management, and storage under normalized conditions and to define QC standards. The general strategy of the Chr-16 HPP and the current state of the different initiatives are discussed.


Assuntos
Cromossomos Humanos Par 16 , Bases de Dados de Proteínas , Proteínas , Proteoma/análise , Linhagem Celular , Cromossomos Humanos Par 16/genética , Cromossomos Humanos Par 16/metabolismo , Expressão Gênica , Genoma Humano , Humanos , Espectrometria de Massas , Proteínas/classificação , Proteínas/genética , Proteínas/metabolismo , Transcriptoma
20.
Opt Express ; 21(18): 21357-64, 2013 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-24104010

RESUMO

The optical Kerr effect exhibited by a nickel doped zinc oxide thin solid film was explored with femto- and pico-second pulses using the z-scan method. The samples were prepared by the ultrasonic spray pyrolysis technique. Opposite signs for the value of the nonlinear refractive index were observed in the two experiments. Self-defocusing together with a two-photon absorption process was observed with 120 ps pulses at 1064 nm, while a dominantly self-focusing effect accompanied by saturated absorption was found for 80 fs pulses at 825 nm. Regarding the nanostructured morphology of the resulting film, we attribute the difference in the two ultrafast optical responses to the different physical mechanism responsible of energy transfer generated by multiphoton processes under electronic and thermal effects.

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