RESUMO
A homologous series of dithiocarbamate ligands derived from N-substituted amino acids was reacted with different diorganotin dichlorides to give 18 diorganotin complexes. Spectroscopic and mass spectrometric analysis evidenced the formation of assemblies with six-coordinate tin atoms embedded in skewed-trapezoidal bipyramidal coordination environments of composition C2SnS2O2. Single-crystal X-ray diffraction analysis for three of the compounds revealed a one-dimensional polymeric structure for the complex with the ligand derived from 5-aminopentanoic acid, which through further intermolecular Sn···O interactions generated an overall two-dimensional coordination polymer containing 40-membered hexanuclear tin macrocycles. On the contrary, the ligands derived from 6-aminohexanoic and 8-aminooctanoic acid provided the expected 22- and 26-membered dinuclear macrocyclic structures. Density functional theory calculations for a representative series of macrocyclic complexes of composition [Me2SnLx]2 with Lx = ¯S2CN(Me)-(CH2)x-COO¯ (x = 3-12) enabled a detailed analysis of the variations in the molecular conformation, shape, and cavity size of the macrocycles in dependence of the aliphatic spacer. Because of odd-even effects, the difunctional ligands can adopt either a curved or a twisted-pincer shape, while the SnSxO4-x (x = 0-4) moieties can act either as linear or angular tectons with varying connectivity angles.
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The aim of this study was to describe the characteristics of vaso-occlusive crises (VOC) in children with sickle cell disease and to identify factors associated with greater severity. We performed a prospective observational study from August 2012 to January 2014. The study population comprised patients with sickle cell disease who consulted at the emergency department (ED) for VOC. We recorded demographic variables, history of complications related to the disease, and data on usual treatment. We also assessed pain, analgesia at home, need for admission, length of stay, and analgesia during admission. Analytical parameters were collected. A total of 29 patients with VOC were included. The patient's usual treatment was hydroxyurea (HU) in 69.0%, and 7.0% required chronic transfusions. In the ED, 90.0% had moderate or severe pain, even though 86.0% had received analgesia at home (41.4% minor opioids). Overall, 27 of the 29 patients were admitted, and 56.0% needed major opioids. Higher lactate dehydrogenase (LDH) levels were related to the use of major opioids during admission (p = 0.038). A significant difference was recorded between the median number of days of admission for patients receiving non-steroidal anti-inflammatory drugs and for those requiring intravenous opioids (p = 0.005). Most patients with VOC were admitted to hospital. Lactate dehydrogenase level in the ED was a predictor of severity and was associated with the need for major opioids during admission and more days of admission.
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Anemia Falciforme/complicações , Arteriopatias Oclusivas/diagnóstico , L-Lactato Desidrogenase/sangue , Índice de Gravidade de Doença , Adolescente , Analgésicos Opioides/uso terapêutico , Criança , Pré-Escolar , Serviço Hospitalar de Emergência , Feminino , Hospitalização , Humanos , Hidroxiureia/uso terapêutico , Masculino , Dor/tratamento farmacológico , Manejo da Dor/métodos , Estudos ProspectivosAssuntos
Betacoronavirus , Infecções por Coronavirus , Neoplasias , Pandemias , Pneumonia Viral , Adolescente , COVID-19 , Criança , Humanos , Pneumonia Viral/epidemiologia , SARS-CoV-2RESUMO
Marginal Abatement Cost Curves compare and assess greenhouse gas mitigation options available to various sectors of the economy. In the Irish agricultural sector, large anaerobic digestion facilities are currently considered a high-cost abatement solution. In prior studies of anaerobic digestion abatement costs, two options were assessed: the generation of heat and electricity from biogas (115 /tCO2eq) and the production of renewable heat from biomethane (280 /tCO2eq). Both scenarios encompass single cost values that may not capture the potentially variable nature of such systems. In contrast, prior techno-economic analyses and lifecycle analyses can provide a comparison of the abatement costs of anaerobic digestion systems at a range of scales. This work compares two case studies (based on prior literature) for small and medium-scale on farm anaerobic digestion systems. The small-scale system is set in Ireland with cattle slurry collected in open tanks during the winter, while the medium-scale system is set in the USA with cattle slurry collected periodically indoors all year-round. It was found that the abatement cost can vary between -117 to +79 per t CO2eq. The key variables that affected the abatement cost were additional revenue streams such as biofertilizer sales, displaced energy savings, and additional incentives and emissions savings within the system boundary. Including only some of these options in the analysis resulted in higher abatement costs being reported. Based on the variation between system topologies and therefore system boundaries, assigning a single mitigation cost to anaerobic digestion systems may not be representative.
The veracity of an abatement cost analysis depends on a clear methodological process.The abatement cost varies based on the processes considered within the system boundary.On-farm digestion abatement costs assessed ranged from -117 to +79 /tCO2eq.On-farm emissions savings ranged from 609 to 10,358 tCO2eq/yr.Abatement costs reduce when considering the income and emissions savings from co-benefits.
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Agricultura , Biocombustíveis , Animais , Bovinos , Fazendas , Anaerobiose , ComércioRESUMO
UNLABELLED: Patients with sickle cell disease have vitamin D deficiency and poor bone health which makes them prone to have an increased risk of fractures and osteoporosis in adulthood. We performed a prospective, cross-sectional study in children diagnosed with sickle cell disease living in Madrid, Spain. The purpose of this study was to evaluate the status of vitamin D of these children. Patients 0-16 years old were enrolled between 2008 and 2011. We studied demographics, calcium metabolism, and bone health, especially by measuring levels of 25-hydroxyvitamin D (25(OH)D), during different seasons of the year, and bone densitometry (beyond 4 years of age). Seventy-eight children were included in the study. Mean age was 4.8 ± 4.3 years, and mean serum 25(OH)D level was 21.50 ± 13.14 ng/ml, with no differences in 25(OH)D levels within different seasons. Fifty-six percent of children had levels of 25(OH) vitamin D of <20 ng/ml, whereas 79 and 18 % of them had levels of <30 and <11 ng/ml, respectively. Secondary hyperparathyroidism was observed in 25 % of children. Densitometry was performed in 33 children, and an abnormal z-score was seen in 15.2 % of them with no correlation with levels of 25(OH)D. CONCLUSIONS: Vitamin D deficiency is highly prevalent in children with sickle cell disease, who are residing in Madrid, Spain, and it is detected at a young age. We propose that early intervention may increase the possibility of an adequate bone density later in life.
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Anemia Falciforme/complicações , Deficiência de Vitamina D/diagnóstico , Adolescente , Algoritmos , Anemia Falciforme/sangue , Biomarcadores/sangue , Densidade Óssea , Conservadores da Densidade Óssea/uso terapêutico , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Prevalência , Estudos Prospectivos , Fatores de Risco , Espanha/epidemiologia , Vitamina D/análogos & derivados , Vitamina D/uso terapêutico , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/epidemiologia , Deficiência de Vitamina D/prevenção & controleRESUMO
Pulmonary tuberculosis (TB) is one of the top 10 causes of death worldwide caused by an infection. TB is curable with an adequate diagnosis, normally performed through bacilloscopies. Automate TB diagnosis implies bacilli detection and counting usually based on smear images processing and artificial intelligence. Works reported in the literature usually consider images with similar coloring characteristics, which are difficult to obtain due to the Ziehl - Neelsen staining method variations (excess or deficiency of coloration), provoking errors in the bacilli segmentation. This paper presents an image preprocessing technique, based on simple, fast and well-known processing techniques, to improve and standardize the contrast in the Acid-Fast Bacilli (AFB) images used to diagnose TB; these techniques are used previously to the segmentation stage to obtain accurate results. The results are validated with and without the preprocessing stage by the Jaccard index, pixel detection accuracy and UAC obtained in an Artificial Neural Network (ANN) and a Bayesian classifier with Gaussian mixture model (GMM). Obtained results indicate that the proposed approach can be applied to automate the Tuberculosis diagnostic.
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Mycobacterium tuberculosis , Tuberculose Pulmonar , Tuberculose , Algoritmos , Inteligência Artificial , Teorema de Bayes , Humanos , Escarro , Tuberculose Pulmonar/diagnóstico por imagemRESUMO
Background: Breast cancer in men is a rare and poorly studied disease, and its treatment is based on women breast cancer studies. However, clinical outcome is not the same in men and women. Basic studies and clinical trials in animal models provide detailed information on cancer, origin, development, cell signaling pathways, sites of metastasis, and target molecules. It is necessary to explore the biology of breast cancer in male animal models that allow observing their similarity. Methods: The triple-negative 4T1 breast cancer model was developed in both male and female mice and studied weekly during 4 weeks. For that, twenty 8-week-old female and male BALB/c mice were used. Sixteen mice (eight males and eight females) were inoculated into the second left thoracic mammary pad with 20,000 4T1 cells, resuspended in 20 µL phosphate-buffered saline (PBS). All samples were processed for immunodetection, characterized histopathologically and immunohistochemically. Results: In this work, we describe the development of a triple-negative 4T1 breast cancer model in male BALB/c mice. Breast tumors were characterized histopathologically at different time points and corresponded to a moderately differentiated invasive ductal carcinoma, estrogen receptor ER-/progesterone receptor PR-/human epidermal growth factor receptor 2 HER2-/Ki67+, with histological grade II (moderately differentiated; a solid mass with occasional duct formation and moderate to severe nuclear pleomorphism), infiltrating the adipose and muscular tissue, and metastasis to lungs. From the results, we did not observe differences in the time of tumor development, necrosis, color change of tumor tissue, and lung metastasis between male and female mice. Even though we did not find histological differences, response to treatment and molecular signaling may be different. Conclusions: The histogenesis of male breast tumors was similar to that of female BALB/c mice. The histological and immunohistochemical characteristics of male tumors also match the features reported for stage IV human breast cancer of men and women. The murine male breast cancer model described here can be a significant tool to explore the molecular mechanisms involved in male breast cancer tumorigenesis and metastasis and may bring new approaches for clinical treatment of triple-negative breast cancer in men.
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BACKGROUND: Several evidence-based guidelines for the management of children with febrile neutropenia (FN) have been published, with special focus in bacterial and fungal infections. However, the role of acute respiratory infections caused by respiratory viruses (RV) has not been clearly established. The aim of this study was to evaluate the epidemiology, clinical presentation and outcome of acute respiratory infections in children with FN. METHODS: Patients, <18 years of age admitted to the Pediatric Oncology-Hematology Unit after developing FN between November 2010 and December 2013, were prospectively included in the study. Children were evaluated by clinical examination and laboratory tests. Nasopharyngeal sample was obtained for detection of RV. RESULTS: There was a total of 112 episodes of FN in 73 children admitted to the hospital during a 32-month period. According to disease severity, 33% of the episodes were considered moderate or severe. Rhinovirus was the most frequently detected RV (66.6%; 24/36), followed by parainfluenza. On regard to clinical outcome, RV-infected children developed fewer episodes of moderate or severe FN compared with non-RV infected children (16.7% vs. 33.3%; P = 0.08). CONCLUSIONS: A great proportion of children with FN admitted to a tertiary hospital had a RV isolation. The rate of this RV isolation was significantly higher when a rapid molecular test was used compared with conventional microbiologic methods. Rhinovirus was the most frequently isolated, although its role as an active agent of acute infection was not clear. Children with FN and a RV isolate had a lower rate of severe disease.
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Neutropenia Febril/virologia , Nasofaringe/virologia , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/virologia , Vírus/isolamento & purificação , Doença Aguda/epidemiologia , Adolescente , Criança , Pré-Escolar , Neutropenia Febril/fisiopatologia , Feminino , Humanos , Masculino , Estudos Prospectivos , Índice de Gravidade de Doença , Espanha/epidemiologia , Centros de Atenção Terciária/estatística & dados numéricos , Vírus/classificaçãoRESUMO
Image segmentation applied to medical image analysis is still a critical and important task. Although there exist several segmentation algorithms that have been widely studied in literature, these are subject to segmentation problems such as over- and under-segmentation as well as non-closed edges. In this paper, a simple method that combines well-known segmentation algorithms is presented. This method is applied to detect acid-fast bacilli (AFB) in bacilloscopies used to diagnose pulmonary tuberculosis (TB). This diagnosis can be performed through different tests, and the most used worldwide is smear microscopy because of its low cost and effectiveness. This diagnosis technique is based on the analysis and counting of the bacilli in the bacilloscopy observed under an optical microscope. The proposed method is used to segment the bacilli in digital images from bacilloscopies processed using Ziehl-Neelsen (ZN) staining. The proposed method is fast, has a low computational cost and good efficiency compared to other methods. The bacilli image segmentation is performed by image processing and analysis techniques, probability concepts and classifiers. In this work, a Bayesian classifier based on a Gaussian mixture model (GMM) is used. The segmentations' results are validated by using the Jaccard index, which indicates the efficiency of the classifier.
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Testes Diagnósticos de Rotina , Microscopia/métodos , Escarro/microbiologia , Tuberculose Pulmonar/diagnóstico , Algoritmos , Teorema de Bayes , Telefone Celular , Humanos , Processamento de Imagem Assistida por Computador , Mycobacterium tuberculosis/isolamento & purificação , Mycobacterium tuberculosis/patogenicidade , Manejo de Espécimes , Escarro/diagnóstico por imagem , Tuberculose Pulmonar/diagnóstico por imagem , Tuberculose Pulmonar/microbiologiaRESUMO
The potassium bis-dithiocarbamate (bis-dtc) salts of 1,3-bis(benzylaminomethyl)benzene (1,3-Bn-ambdtc), 1,3-bis(iso-butylaminomethyl)benzene (1,3-(i)Bu-ambdtc), 1,4-bis(benzylaminomethyl)benzene (1,4-Bn-ambdtc), and 1,4-bis(iso-butylaminomethyl)benzene (1,4-(i)Bu-ambdtc) were reacted with three different diorganotin dichlorides (R2SnCl2 with R = Me, (n)Bu, and Ph) in 1:1 stoichiometric ratios to give the corresponding diorganotin bis-dithiocarbamates. Additionally, the dimethyltin bis-dithiocarbamate of 1,1'-bis(benzylaminomethyl)ferrocene (1,1'-Bn-amfdtc) was prepared. The resulting complexes have been characterized as far as possible by elemental analysis, FAB(+) mass spectrometry, IR and NMR ((1)H, (13)C, and (119)Sn) spectroscopy, and single-crystal X-ray diffraction, showing that the tin complexes are dinuclear 24- and 26-membered macrocyclic species of composition [{R2Sn(bis-dtc)}2]. As shown by (119)Sn NMR spectroscopy, the tin centers are hexa-coordinated in all cases; however, two different coordination environments are possible, as detected by single-crystal X-ray diffraction. In the dimethyltin derivatives of 1,3-Bn-ambdtc, 1,3-(i)Bu-ambdtc, 1,4-Bn-ambdtc, and 1,1'-Bn-amfdtc and the di-n-butyltin derivative of 1,3-(i)Bu-ambdtc, the metal atoms are embedded in skewed-trapezoidal-bipyramidal coordination polyhedra with asymmetrically coordinating trans-oriented dtc groups. In contrast, in the diphenyltin derivative 1,3-(i)Bu-ambdtc, the metal centers have distorted octahedral coordination with symmetrically coordinating cis-oriented dtc functions. Thus, for the complexes derived from 1,3-Bn/(i)Bu-ambdtc, two different macrocyclic structures were observed. In the dimethyl- and di-n-butyltin derivatives, the bridging bis-dtc ligands adopt U-shaped conformations, while in the case of the diphenyltin derivative, the conformation is L-shaped. Furthermore, two different macrocyclic ring conformations can occur, which differ in the spatial orientation of the substituents attached to the nitrogen atoms (Bn or (i)Bu). The dimethyltin derivatives of 1,4-Bn-ambdtc and 1,1'-Bn-amfdtc have cavities, in which aromatic rings are accommodated in the solid state.
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The dimethyl-, di-n-butyl-, and diphenyltin(IV) dithiocarbamate (dtc) complexes [{R2Sn(L-dtc)}x] 1-7 (1, L = L1, R = Me; 2, L = L1, R = n-Bu; 3, L = L2, R = Me, x = infinity; 4, L = L2, R = n-Bu; 5, L = L3, R = Me, x = 2; 6, L = L3, R = n-Bu, x = 2; 7, L = L3, R = Ph, x = 2) have been prepared from a series of secondary amino acid (AA) homologues as starting materials: N-benzylglycine (alpha-AA derivative = L1), N-benzyl-3-aminopropionic acid (beta-AA derivative = L2), and N-benzyl-4-aminobutyric acid (gamma-AA derivative = L3). The resulting compounds have been characterized by elemental analysis, mass spectrometry, IR and NMR ((1)H, (13)C, and (119)Sn) spectroscopy, thermogravimetric analysis, and X-ray crystallography, showing that in all complexes both functional groups of the heteroleptic ligands are coordinated to the tin atoms. By X-ray diffraction analysis, it could be shown that [{Me2Sn(L2-dtc)}x] (3) is polymeric in the solid state, while the complexes derived from L3 (5-7) have dinuclear 18-membered macrocyclic structures of the composition [{R2Sn(L3-dtc)}2]. For the remaining compounds, it could not be established with certainty whether the structures are macrocyclic or polymeric. A theoretical investigation at the B3LYP/SBKJC(d,p) level of theory indicated that the alpha-AA-dtc complexes might have trinuclear macrocyclic structures. The macrocyclic complexes 5-7 have a double-calix-shaped conformation with two cavities large enough for the inclusion of aliphatic and aromatic guest molecules. They are self-complementary for the formation of supramolecuar synthons that give rise to 1D molecular arrangements in the solid state. Preliminary recognition experiments with tetrabutylammonium acetate have shown that the [{R2Sn(L3-dtc)}2] macrocycles 6 and 7 might interact simultaneously with anions (AcO(-)), which coordinate to the tin atoms, and organic cations (TBA(+)), which accommodate within the hydrophobic cavity (ion-pair recognition).
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Aminoácidos/química , Compostos Macrocíclicos/química , Compostos Orgânicos de Estanho/química , Tiocarbamatos/química , Ânions/química , Cátions/química , Cristalografia por Raios X , Interações Hidrofóbicas e Hidrofílicas , Ligantes , Compostos Macrocíclicos/síntese química , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Compostos Orgânicos de Estanho/síntese química , Espectrofotometria Infravermelho , Termogravimetria , Tiocarbamatos/síntese químicaRESUMO
The combination of two heteroaromatic boronic acids with pentaerythritol gave self-complementary tectons which were suitable for the generation of 2D and 3D molecular networks.
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Se realiza una revisión de las estadísticas de la División de Medicina del Tarbajo del IVSS sobre enfermedades profesionales, la cual es coincidente con la encontrada en Sidor. Considera que al presente se carece de un diagnóstico real sobre la epidemiología ocupacional en nuestro país y falta de cumplimiento de planes y políticas de prevención y asistencia médica adecuados al desarrollo de la nación. También hace evaluación de planes futuros para el desarrollo de los nuevos escenarios que obligatoriamente se presentarán en Venezuela. Comenta los programas, metas y recomendaciones de la OPS-OMS en su Plan Decenal de Salud y de la resolución 3043 de este último
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Fatores de Risco , Saúde Ocupacional , Saúde Ocupacional/normas , Doenças Profissionais/epidemiologia , Doenças Profissionais/estatística & dados numéricos , Medicina do Trabalho/legislação & jurisprudência , Exposição OcupacionalRESUMO
Durante un programa de salud oral para estudiantes de primer año de la Facultad de Odontología, Universidad de Chile, se analizó el grado de contaminación microbiana de 40 cepillos dentales un número igual de alumnos, para ser sometidos a un estudio microbiológico y detectar bacterias y levaduras bucales. Los cepillos dentales se retiraron sin importar su estado, marca comercial, calidad ni el tiempo de uso, a su vez, cada alumno recibió uno nuevo. Cada cepillo usado fue envasado en una bolsa de papel estéril, una vez en el laboratorio, se colocaron en un tubo con medio de thioglicolato por su parte activa donde fueron incubados por 24 horas. Posteriormente, de cada tubo se tomaron muestras (100 µL en cada uno) y se sembraron en diversos medios de cultivo Agar TYCSB, Agar Sabureaud + CAF, Agar LBS y Agar sangre + hemina + menadiona, medios que son selectivos para: S. mutans, Cándidas Lactobacilos y Anaerobios totales, respectivamente. Los resultados de los cultivos, mostraron un pequeño porcentaje de S. mutans (2,8 por ciento), de Cándidas (2,8 por ciento), de Lactobacilos (1,2 por ciento), pero sorprendentemente, para los anaerobios totales, fue de (100 por ciento), éste último valor, puede deberse a una gran cantidad de factores, entre ellos: calidad de las pastas dentales, las cuales contienen químicos que inhiben a ciertos microorganismos y poseen fuertes propiedades antienzimáticas. También es posible, que las bacterias anaeróbicas, deriven de esa película bacteriana que se deposita en el plástico en que se insertan las cerdas del cepillo de dientes