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1.
Sensors (Basel) ; 24(9)2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38732785

RESUMO

Given the high relevance and impact of ransomware in companies, organizations, and individuals around the world, coupled with the widespread adoption of mobile and IoT-related devices for both personal and professional use, the development of effective and efficient ransomware mitigation schemes is a necessity nowadays. Although a number of proposals are available in the literature in this line, most of them rely on machine-learning schemes that usually involve high computational cost and resource consumption. Since current personal devices are small and limited in capacities and resources, the mentioned schemes are generally not feasible and usable in practical environments. Based on a honeyfile detection solution previously introduced by the authors for Linux and Window OSs, this paper presents a ransomware detection tool for Android platforms where the use of trap files is combined with a reactive monitoring scheme, with three main characteristics: (i) the trap files are properly deployed around the target file system, (ii) the FileObserver service is used to early alert events that access the traps following certain suspicious sequences, and (iii) the experimental results show high performance of the solution in terms of detection accuracy and efficiency.

2.
Physiol Plant ; 175(4): e13971, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37616015

RESUMO

Halophyte-based intercropping appears nowadays as a valuable approach in soil remediation and agriculture. In this work, intercropping between the halophyte Arthrocaulon macrostachyum and tomato (Solanum lycopersicum var. Sargento) was studied in both plant species using comparative mass spectrometry-based metabolomics coupled to metabolic pathway predictions. A significant number of changes in metabolites was observed in the halophyte. In terms of alteration of specific metabolic pathways, intercropping conditions stimulated sugar and starch metabolisms in tomato, whereas in the halophyte, intercropping mainly altered amino acid-related pathways. In addition, arginine and proline metabolism were commonly affected in both tomato and halophyte plants. Moreover, metabolomic changes were associated with physiological alterations in tomato. In this sense, mild oxidative stress was induced in intercropped tomato plants, which, in turn, could trigger signaling events leading to plant adjustment to intercropping conditions. This study represents the first approach toward understanding intercropping interactions at the metabolome level and its effect on plant physiology, opening up prospects for further characterization of this crop cultivation strategy.


Assuntos
Plantas Tolerantes a Sal , Solanum lycopersicum , Agricultura , Metabolômica , Solo
3.
Gac Med Mex ; 158(2): 69-77, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35763826

RESUMO

INTRODUCTION: In pregnant women, a higher risk for developing viral respiratory infections is identified. OBJECTIVE: To analyze sociodemographic characteristics, evolution, clinical manifestations, and complications of pregnant women hospitalized with COVID-19. METHODS: Study conducted at 11 public hospitals; sociodemographic variables, comorbidities, signs and symptoms, laboratory and imaging findings, pregnancy characteristics, treatment and pregnancy outcome were included for analysis. RESULTS: Age ranged between 15 and 40 years; 85.1% were at third trimester of pregnancy, 11.9% at second and 3% at first; 27% had any comorbidity such as obesity, hypertension or asthma; 89.5% had fever, 73.1% cough, 44.8% dyspnea, 43.3% headache and 35.8% myalgia. Diagnoses were mild disease (55.2%), mild pneumonia (26.9%), severe pneumonia (10.4%), severe pneumonia with acute respiratory distress syndrome (4.5%), and severe pneumonia with septic shock (3%); 76.2% had noninvasive oxygen support, and 9%, mechanical ventilation. Pregnancy was interrupted in 53.8%; 95.5% were discharged due to improvement of their condition and 4.5% died. CONCLUSIONS: Age range and symptoms are consistent with those previously reported. Evidence was found of an increase in cesarean section without a clear indication in women with COVID-19.


INTRODUCCIÓN: En las mujeres embarazadas se identifica mayor riesgo de desarrollar infecciones respiratorias virales. OBJETIVO: Analizar características sociodemográficas, evolución, manifestaciones clínicas y complicaciones en mujeres embarazadas con COVID-19 que fueron hospitalizadas. MÉTODOS: Estudio en 11 hospitales públicos; se incluyeron variables sociodemográficas, comorbilidades, síntomas y signos, hallazgos de laboratorio y gabinete, características del embarazo, tratamiento y desenlace de la gestación. RESULTADOS: La edad osciló entre 15 y 40 años; 85.1 % cursaba el tercer trimestre del embarazo, 11.9 % el segundo y 3 % el primero; 27 % presentó alguna comorbilidad como obesidad, hipertensión o asma; 89.5 % presentó fiebre, 73.1 % tos, 44.8 % disnea, 43.3 % cefalea y 35.8 % mialgias. Los diagnósticos fueron enfermedad leve (55.2 %), neumonía leve (26.9 %), neumonía severa (10.4 %), neumonía severa con síndrome de distrés respiratorio agudo (4.5 %) y neumonía severa con choque séptico (3 %); 76.2 % recibió soporte de oxígeno no invasivo y 9 %, ventilación mecánica. Se interrumpió el embarazo en 53.8 %; 95.5 % egresó por mejoría y 4.5 % falleció. CONCLUSIONES: El rango de edad y los síntomas coinciden con los señalados en la literatura especializada. En mujeres con COVID-19 se evidenció el incremento de la operación cesárea sin una indicación clara.


Assuntos
COVID-19 , Pneumonia , Complicações Infecciosas na Gravidez , Adolescente , Adulto , COVID-19/epidemiologia , COVID-19/terapia , Cesárea , Feminino , Humanos , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/terapia , Resultado da Gravidez , Gestantes , Adulto Jovem
4.
Am J Transplant ; 21(7): 2596-2599, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33754452

RESUMO

We present the case of a 3-year-old female liver transplant recipient with a history of Caroli disease who presented with positive severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reverse transcription polymerase chain reaction (RT-PCR) test and was ultimately diagnosed with multisystem inflammatory syndrome in children (MIS-C) complicated by portal vein thrombosis. To the best of our knowledge, this is the first case report of MIS-C in a pediatric solid organ transplant (SOT) recipient. Based on our patient, MIS-C could be a potential complication of Coronavirus disease 2019 (COVID-19) in SOT recipients and may have a negative outcome on transplant graft function.


Assuntos
COVID-19 , Transplante de Órgãos , Criança , Pré-Escolar , Feminino , Humanos , Transplante de Órgãos/efeitos adversos , SARS-CoV-2 , Síndrome de Resposta Inflamatória Sistêmica , Transplantados
5.
Nanotechnology ; 32(9): 095705, 2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33202386

RESUMO

Antimony selenide (Sb2Se3) is a material widely used in photodetectors and relatively new as a possible material for thermoelectric applications. Taking advantage of the new properties after nanoscale fabrication, this material shows great potential for the development of efficient low temperature thermoelectric devices. Here we study the synthesis, the crystal properties and the thermal and thermoelectric transport response of Sb2Se3 hexagonal nanotubes (HNT) in the temperature range between 120 and 370 K. HNT have a moderate electrical conductivity ∼102 S m-1 while maintaining a reasonable Seebeck coefficient ∼430 µV K-1 at 370 K. The electrical conductivity in Sb2Se3 HNT is about 5 orders of magnitude larger and its thermal conductivity one half of what is found in bulk. Moreover, the calculated figure of merit (ZT) at room temperature is the largest value reported in antimony selenide 1D structures.

6.
Molecules ; 26(22)2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34834010

RESUMO

Some nitroaromatic compounds are found in wastewater from industries such as the weapons industry or the wine industry. One of these compounds is 3,5-dinitrosalicylic acid (DNS), widely used in various tests and frequently found as an emerging pollutant in wastewater and to which the required attention has not been given, even though it may cause serious diseases due to its high toxicity. This study investigated the adsorption of DNS using granulated activated carbon (GAC) and powdered activated carbon (PAC) at different temperatures. The results show that in equilibrium, the adsorption takes place in more than one layer and is favorable for the removal of DNS in both GAC and PAC; The maximum adsorption capacity was obtained at 45 °C, with values of 6.97 mg/g and 11.57 mg/g, respectively. The process is spontaneous and exothermic. In addition, there was a greater disorder in the solid-liquid interface during the desorption process. The predominant kinetics using GAC (7.14 mg/g) as an adsorbent is Elovich, indicating that there are heterogeneous active sites, and when PAC (10.72 mg/g) is used, Pseudo-second order kinetics predominate, requiring two active sites for DNS removal. External mass transfer limitations are only significant in GAC, and ATR-FTIR studies in PAC demonstrated the participation of functional groups present on the adsorbent surface for DNS adsorption.

7.
J Vasc Bras ; 20: e20200024, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34925471

RESUMO

BACKGROUND: Open surgical repair (OSR) and endovascular aneurysm repair (EVAR) surgery are alternative treatments for infrarenal abdominal aortic aneurysm (IRAAA). OBJECTIVES: To compare OSR and EVAR for the treatment of IRAAA. METHODS: 119 patients with IRAAA were electively operated by the same surgeon between January 1, 2006 and December 31, 2015, following selection for OSR or EVAR according to surgical risk. Complications, reinterventions, failures, and early and late mortality were analyzed. RESULTS: 63 OSR and 56 EVAR patients were analyzed. They were similar in terms of age (70 years), gender (92% men), and average diameter of IRAAA (6.5 cm), but with different comorbidities, surgical risk, and anatomy. EVAR was better than OSR regarding time in the operating theatre (177.5 vs. 233.3 minutes), need for transfusion (25 vs. 73%), and length of stay in ICU (1.3 vs. 3.3 days) and hospital (8.1 vs. 11.1 days). OSR allowed more associated procedures to be conducted simultaneously (19.0 vs. 1.8%). There were no significant differences between the groups with respect to complications (25.4 vs. 25.1%), reinterventions (3.2 vs. 5.2%), or early mortality (1.6 vs. 0%). During follow-up, OSR was associated with fewer revisions (3.13 vs. 4.21), angio-CTs (0.22 vs. 3.23), complications (6.4 vs. 37.5%), reinterventions (3.2 vs. 23.2%), and failures (1.6 vs. 10.7%), and had better survival (78.2 vs. 63.2%). CONCLUSIONS: Correct selection of patients achieves excellent results because it avoids OSR in patients at high risk and avoids EVAR in patients with high anatomical complexity, achieving similar results in the perioperative period, but better results for OSR over the course of follow-up.


CONTEXTO: A cirurgia aberta (CA) e o reparo endovascular de aneurisma (REVA) são tratamentos alternativos para o aneurisma da aorta abdominal infrarrenal (AAAIR). OBJETIVOS: Comparar CA e REVA no tratamento do AAAIR. MÉTODOS: Foram incluídos 119 pacientes com AAAIR, operados eletivamente pelo mesmo cirurgião entre 1 de janeiro de 2006 e 31 de dezembro de 2015, após seleção para CA ou REVA de acordo com o risco cirúrgico. Complicações, reintervenções, falhas e mortalidade precoce e tardia foram analisadas. RESULTADOS: Foram analisados 63 pacientes de CA e 56 de REVA, com semelhanças de idade (70 anos), sexo (92% homens) e diâmetro médio do AAAIR (6,5 cm), mas com diferentes comorbidades, riscos cirúrgicos e anatomias. O REVA foi melhor que a CA em relação ao tempo na sala de cirurgia (177,5 vs. 233,3 minutos), necessidade de transfusão (25 vs. 73%) e tempo de permanência na unidade de terapia intensiva (1,3 vs. 3,3 dias) e no hospital (8,1 vs. 11,1 dias). A CA permitiu que mais procedimentos associados fossem realizados simultaneamente (19,0 vs. 1,8%). Não houve diferenças significativas entre os grupos em relação a complicações (25,4 vs. 25,1%), reintervenções (3,2 vs. 5,2%) e mortalidade precoce (1,6 vs. 0%). Durante o acompanhamento, a CA apresentou menos revisões (3,13 vs. 4,21), angiotomografias (0,22 vs. 3,23), complicações (6,4 vs. 37,5%), reintervenções (3,2 vs. 23,2%) e falhas (1,6 vs. 10,7%), além de ter melhor sobrevida (78,2 vs. 63,2%). CONCLUSÕES: A seleção correta dos pacientes proporciona excelentes resultados porque evita pacientes com alto risco para CA e com complexidade anatômica para REVA. Os resultados são semelhantes no período perioperatório, mas melhores para CA durante o acompanhamento.

8.
J Exp Bot ; 71(16): 4843-4857, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32309856

RESUMO

Root system architecture results from a highly plastic developmental process to adapt to environmental conditions. In particular, the development of lateral roots and root hair growth are constantly optimized to the rhizosphere properties, including biotic and abiotic constraints. The development of the root system is tightly controlled by auxin, the driving morphogenic hormone in plants. Glutathione, a major thiol redox regulator, is also critical for root development but its interplay with auxin is scarcely understood. Previous work showed that glutathione deficiency does not alter root responses to indole acetic acid (IAA), the main active auxin in plants. Because indole butyric acid (IBA), another endogenous auxinic compound, is an important source of IAA for the control of root development, we investigated the crosstalk between glutathione and IBA during root development. We show that glutathione deficiency alters lateral roots and root hair responses to exogenous IBA but not IAA. Detailed genetic analyses suggest that glutathione regulates IBA homeostasis or conversion to IAA in the root cap. Finally, we show that both glutathione and IBA are required to trigger the root hair response to phosphate deprivation, suggesting an important role for this glutathione-dependent regulation of the auxin pathway in plant developmental adaptation to its environment.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Ácido Butírico , Glutationa , Ácidos Indolacéticos , Indóis , Fosfatos , Raízes de Plantas
9.
Molecules ; 25(21)2020 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-33153206

RESUMO

Concentrated orange oils (5x, 10x, 20x) are ingredients used in different industries as components of flavors and aromas due to their great organoleptic qualities. This research focuses on the search for alternative uses for their application through encapsulation in inclusion complexes with ß-cyclodextrin (ß-CD). Inclusion complexes of concentrated orange oils (COEO) and ß-CD were developed by the co-precipitated method in ratios of 4:96, 12:88, and 16:84 (w/w, COEO: ß-CD). The best powder recovery was in the ratio 16:84 for the three oils, with values between 82% and 84.8%. The 20x oil in relation 12:88 showed the highest entrapment efficiency (89.5%) with 102.3 mg/g of ß-CD. The FT-IR analysis may suggest an interaction between the oil and the ß-CD. The best antioxidant activity was observed in the ratio 12:88 for the three oils. The antifungal activity was determined for all the inclusion complexes, and the 10x fraction showed the highest inhibition at a concentration of 10 mg/mL in ratios 12:88 and 16:84. Antibacterial activity was determined by the minimum inhibitory concentration (MIC) and was found at a concentration of 1.25 mg/mL in ratios 12:88 and 16:84 for 5x and 20x oils.


Assuntos
Antibacterianos , Antifúngicos , Antioxidantes , Óleos de Plantas , beta-Ciclodextrinas , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Óleos de Plantas/química , Óleos de Plantas/farmacologia , beta-Ciclodextrinas/química , beta-Ciclodextrinas/farmacologia
10.
Molecules ; 25(2)2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31936683

RESUMO

Stenocereus thurberi is an endemic species in northwestern Mexico. It produces colorful fruits called pitayas that have an edible pulp. They have phytochemical compounds associated with biological activities. Ultrafiltration is a widely used method for the clarification of fruit juices and the recovery of phytochemicals. However, its effect has not been extensively studied in extracts. Therefore, the objective of this work is to study the effect of the ultrafiltration of pitaya extract (Stenocereus thurberi) on its phytochemical content, antioxidant capacity, and identification of phenolic compounds by UPLC-DAD-MS, providing greater knowledge about the pitaya. In this study, two extracts were analyzed, the unclarified extract (UE) and the clarified extract (CE). The antioxidant capacity was higher in the CE with 15.93 ± 0.42 mM TE/g, DPPH and 18.37 ± 0.016 mM TE/g, ABTS. The UPLC-MS analysis indicated the decrease in phenolic compounds in the CE and the presence of gallic acid and resorcinol, compounds that had not been identified in other species of Stenocereus spp. The correlation analysis indicated that all the phytochemicals present in the pitaya contribute significantly to the antioxidant capacity. The ultrafiltration process could be a viable option to improve the biological activity of the natural extracts.


Assuntos
Antioxidantes/química , Cactaceae/química , Fenóis/química , Compostos Fitoquímicos/química , Cromatografia Líquida de Alta Pressão , Flavonoides/química , Flavonoides/isolamento & purificação , Frutas , México , Fenóis/isolamento & purificação , Compostos Fitoquímicos/isolamento & purificação , Extratos Vegetais/química , Espectrometria de Massas em Tandem , Ultrafiltração
11.
J Transl Med ; 17(1): 198, 2019 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-31185999

RESUMO

BACKGROUND: Diffuse large B-cell lymphoma (DLBCL) is classified into germinal center-like (GCB) and non-germinal center-like (non-GCB) cell-of-origin groups, entities driven by different oncogenic pathways with different clinical outcomes. DLBCL classification by immunohistochemistry (IHC)-based decision tree algorithms is a simpler reported technique than gene expression profiling (GEP). There is a significant discrepancy between IHC-decision tree algorithms when they are compared to GEP. METHODS: To address these inconsistencies, we applied the machine learning approach considering the same combinations of antibodies as in IHC-decision tree algorithms. Immunohistochemistry data from a public DLBCL database was used to perform comparisons among IHC-decision tree algorithms, and the machine learning structures based on Bayesian, Bayesian simple, Naïve Bayesian, artificial neural networks, and support vector machine to show the best diagnostic model. We implemented the linear discriminant analysis over the complete database, detecting a higher influence of BCL6 antibody for GCB classification and MUM1 for non-GCB classification. RESULTS: The classifier with the highest metrics was the four antibody-based Perfecto-Villela (PV) algorithm with 0.94 accuracy, 0.93 specificity, and 0.95 sensitivity, with a perfect agreement with GEP (κ = 0.88, P < 0.001). After training, a sample of 49 Mexican-mestizo DLBCL patient data was classified by COO for the first time in a testing trial. CONCLUSIONS: Harnessing all the available immunohistochemical data without reliance on the order of examination or cut-off value, we conclude that our PV machine learning algorithm outperforms Hans and other IHC-decision tree algorithms currently in use and represents an affordable and time-saving alternative for DLBCL cell-of-origin identification.


Assuntos
Algoritmos , Perfilação da Expressão Gênica , Centro Germinativo/patologia , Linfoma Difuso de Grandes Células B/classificação , Linfoma Difuso de Grandes Células B/patologia , Aprendizado de Máquina , Adulto , Idoso , Idoso de 80 Anos ou mais , Linfócitos B/patologia , Teorema de Bayes , Árvores de Decisões , Análise Discriminante , Feminino , Perfilação da Expressão Gênica/métodos , Perfilação da Expressão Gênica/estatística & dados numéricos , Humanos , Imuno-Histoquímica/métodos , Imuno-Histoquímica/estatística & dados numéricos , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/metabolismo , Masculino , Pessoa de Meia-Idade
12.
Eur J Orthop Surg Traumatol ; 29(3): 633-638, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30367280

RESUMO

BACKGROUND: Injury to the anterior cruciate ligament (ACL) not only causes mechanical instability but also produces proprioceptive deficit with an altered neuromuscular response. After ACL reconstruction, patients in general continue to complain of a feeling of knee instability. The objective of our study was to assess patient proprioception and its evolution over time by measuring the muscle latency time during a dynamic activity. METHODS: Twenty-five patients with an ACL tear following sports injuries were included in a prospective, comparative, matched controlled study. The study group consisted of the injured knees in those patients, while the control group consisted of the contralateral non-injured knee in the same patients. The neuromuscular response in five leg muscles (vastus medialis, vastus lateralis, rectus femoris, semitendinosus and biceps femoris) was measured during a dynamic activity through the muscle latency time via the use of electromyography. RESULTS: The comparison of the reaction time in the vastus medialis showed that time in the injured knee was longer at pre-op, but it reduced over time reaching a value at 6 months post-op that was close to the reaction time in the non-injured knee group. In the rectus femoris, biceps femoris and semitendinosus muscles, the reaction times in the injured knee group were similar to those in the non-injured knee group at pre-op and post-op visits. CONCLUSION: Before ACL surgery, the muscle latency time of the vastus medialis was significantly longer in the injured knee group than in the non-injured knee group. 'Muscle reflex reaction' as a response during a dynamic task improved in the ACL reconstructed patients at 6 months post-op. LEVEL OF EVIDENCE: Prospective, comparative, matched controlled study.


Assuntos
Lesões do Ligamento Cruzado Anterior/fisiopatologia , Lesões do Ligamento Cruzado Anterior/cirurgia , Músculos Isquiossurais/fisiopatologia , Músculo Quadríceps/fisiopatologia , Tempo de Reação , Adolescente , Adulto , Reconstrução do Ligamento Cruzado Anterior , Eletromiografia , Feminino , Humanos , Escore de Lysholm para Joelho , Masculino , Movimento , Propriocepção , Estudos Prospectivos , Adulto Jovem
13.
Am J Hematol ; 93(7): 867-873, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29658143

RESUMO

The means of optimally managing very elderly patients with diffuse large B-cell lymphoma (DLBCL) has not been established. We retrospectively analyzed 252 patients aged 80-100 years, diagnosed with DLBCL or grade 3B follicular lymphoma, treated in 19 hospitals from the GELTAMO group. Primary objective was to analyze the influence of the type of treatment and comorbidity scales on progression-free survival (PFS) and overall survival (OS). One hundred sixty-three patients (63%) were treated with chemotherapy that included anthracyclines and/or rituximab, whereas 15% received no chemotherapeutic treatment. With a median follow-up of 44 months, median PFS and OS were 9.5 and 12.5 months, respectively. In an analysis restricted to the 205 patients treated with any kind of chemotherapy, comorbidity scales did not influence the choice of treatment type significantly. Independent factors associated with better PFS and OS were: age < 86 years, cumulative illness rating scale (CIRS) score < 6, intermediate risk (1-2) R-IPI, and treatment with R-CHOP at full or reduced doses. We developed a prognostic model based on the multivariate analysis of the 108 patients treated with R-CHOP-like: median OS was 45 vs. 12 months (P = .001), respectively, for patients with 0-1 vs. 2-3 risk factors (age > 85 years, R-IPI 3-5 or CIRS > 5). In conclusion, treatment with R-CHOP-like is associated with good survival in a significant proportion of patients. We have developed a simple prognostic model that may aid the selection patients who could benefit from a curative treatment, although it needs to be validated in larger series.


Assuntos
Linfoma Difuso de Grandes Células B/diagnóstico , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Murinos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ciclofosfamida/uso terapêutico , Gerenciamento Clínico , Doxorrubicina/uso terapêutico , Humanos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/mortalidade , Prednisona/uso terapêutico , Prognóstico , Estudos Retrospectivos , Rituximab , Espanha , Análise de Sobrevida , Vincristina/uso terapêutico
14.
Nanotechnology ; 29(36): 364001, 2018 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-29901451

RESUMO

Highly crystalline indium tin oxide (ITO) nanowires were grown via a vapor-liquid-solid method, with thermal tolerance up to ∼1300 °C. We report the electric and thermoelectric properties of the ITO nanowires before and after heat treatments and draw conclusions about their applicability as thermoelectric building blocks in nanodevices that can operate in high temperature conditions. The Seebeck coefficient and the thermal and electrical conductivities were measured in each individual nanowire by means of specialized micro-bridge thermometry devices. Measured data was analyzed and explained in terms of changes in charge carrier density, impurities and vacancies due to the thermal treatments.

15.
Int J Med Microbiol ; 307(4-5): 241-248, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28412040

RESUMO

The hypothetical role played by the intracellular formation of reactive oxygen species (ROS) in the fungicidal action carried out by Amphotericin B (AmB) and Micafungin (MF) was examined in Candida albicans, which remains the most prevalent fungal pathogen. The clinical MICs for MF and AmB were 0.016 and 0.12µg/ml, respectively. Whereas AmB (0.5-1.0×MIC) induced a marked production of intracellular ROS accompanied by a high degree of cell killing in the C. albicans SC5314 strain, the fungicidal effect of MF was still operative, but ROS generation was slight. Preincubation with thiourea suppressed the formation of ROS and caused a marked increase in cell viability, regardless of the antifungal used. Simultaneous measurement of several well established antioxidant enzymes (catalase, glutathione reductase and superoxide dismutase) revealed strong AmB-induced activation of the three enzymatic activities, whereas MF only had a weak stimulating effect. Likewise, AmB but not MF promoted a conspicuous rise in the mitochondrial membrane potential together with the intracellular synthesis of trehalose, the non-reducing disaccharide which acts as a specific protector against oxidative stress in C. albicans. Optical and electronic microscopy analysis revealed a significant damage to cell integrity and structural alterations caused by both antifungals. Taken together, our results strongly suggest that the induction of an internal oxidative stress in C. albicans through the accumulation of ROS is a preferential contributory factor to the antifungal action of a widely used polyene (AmB) but not of MF (echinocandin).


Assuntos
Anfotericina B/farmacologia , Candida albicans/efeitos dos fármacos , Equinocandinas/farmacologia , Lipopeptídeos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Antifúngicos/farmacologia , Antioxidantes/farmacologia , Candida albicans/metabolismo , Micafungina , Testes de Sensibilidade Microbiana , Estresse Oxidativo/efeitos dos fármacos
17.
Acta Obstet Gynecol Scand ; 96(10): 1205-1213, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28574580

RESUMO

INTRODUCTION: The purpose of this study was to describe the echographic features and perinatal outcomes of fetuses with absence of ductus venosus. MATERIAL AND METHODS: Retrospective review of 10 cases with absence of ductus venosus diagnosed by prenatal ultrasonography between January 2014 and February 2016 at a single referral center. Prenatal findings, umbilical shunting type, perinatal outcomes, and autopsy reports were reviewed. RESULTS: A total of 11 491 fetuses underwent a first- and second-trimester screening during the study period. Ten cases of absence of ductus venosus were diagnosed. All of the fetuses presented an extrahepatic shunt: three fetuses from the umbilical vein to the right atrium and the seven remaining fetuses from the umbilical vein to the inferior vena cava. Major structural defects and fetal effusions were detected in six fetuses. There were two cases of chromosomal abnormalities. Five patients underwent legal termination of pregnancy and five decided to carry to term. In two of these, the absence of ductus venosus anomaly was isolated and had a normal outcome. In the remaining three cases, a follow up of the children showed a variety of adverse outcomes. CONCLUSIONS: The absence of ductus venosus is associated with high rates of adverse perinatal outcomes. The prognosis for this group of anomalies depends on the additional findings with targeted ultrasound. This pathology should lead to a detailed anatomical study and affected fetuses should be closely monitored for signs of congestive heart failure.


Assuntos
Anormalidades Congênitas/epidemiologia , Doenças Fetais/diagnóstico por imagem , Feto/irrigação sanguínea , Veias Umbilicais/anormalidades , Humanos , Estudos Retrospectivos , Ultrassonografia Pré-Natal , Veias Umbilicais/diagnóstico por imagem
18.
J Exp Bot ; 66(1): 25-35, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25336685

RESUMO

Plum pox virus (PPV), the causal agent of sharka disease, is one of the most studied plant viruses, and major advances in detection techniques, genome characterization and organization, gene expression, transmission, and the description of candidate genes involved in PPV resistance have been described. However, information concerning the plant response to PPV infection is very scarce. In this review, we provide an updated summary of the research carried out to date in order to elucidate how plants cope with PPV infection and their response at different levels, including the physiological, biochemical, proteomic, and genetic levels. Knowledge about how plants respond to PPV infection can contribute to the development of new strategies to cope with this disease. Due to the fact that PPV induces an oxidative stress in plants, the bio-fortification of the antioxidative defences, by classical or biotechnological approaches, would be a useful tool to cope with PPV infection. Nevertheless, there are still some gaps in knowledge related to PPV-plant interaction that remain to be filled, such as the effect of PPV on the hormonal profile of the plant or on the plant metabolome.


Assuntos
Doenças das Plantas/virologia , Fenômenos Fisiológicos Vegetais , Vírus Eruptivo da Ameixa/fisiologia , Estresse Oxidativo , Doenças das Plantas/genética , Doenças das Plantas/prevenção & controle
19.
J Exp Bot ; 66(3): 863-78, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25392479

RESUMO

Drought stress conditions modify source-sink relations, thereby influencing plant growth, adaptive responses, and consequently crop yield. Invertases are key metabolic enzymes regulating sink activity through the hydrolytic cleavage of sucrose into hexose monomers, thus playing a crucial role in plant growth and development. However, the physiological role of invertases during adaptation to abiotic stress conditions is not yet fully understood. Here it is shown that plant adaptation to drought stress can be markedly improved in tomato (Solanum lycopersicum L.) by overexpression of the cell wall invertase (cwInv) gene CIN1 from Chenopodium rubrum. CIN1 overexpression limited stomatal conductance under normal watering regimes, leading to reduced water consumption during the drought period, while photosynthetic activity was maintained. This caused a strong increase in water use efficiency (up to 50%), markedly improving water stress adaptation through an efficient physiological strategy of dehydration avoidance. Drought stress strongly reduced cwInv activity and induced its proteinaceous inhibitor in the leaves of the wild-type plants. However, the CIN1-overexpressing plants registered 3- to 6-fold higher cwInv activity in all analysed conditions. Surprisingly, the enhanced invertase activity did not result in increased hexose concentrations due to the activation of the metabolic carbohydrate fluxes, as reflected by the maintenance of the activity of key enzymes of primary metabolism and increased levels of sugar-phosphate intermediates under water deprivation. The induced sink metabolism in the leaves explained the maintenance of photosynthetic activity, delayed senescence, and increased source activity under drought stress. Moreover, CIN1 plants also presented a better control of production of reactive oxygen species and sustained membrane protection. Those metabolic changes conferred by CIN1 overexpression were accompanied by increases in the concentrations of the senescence-delaying hormone trans-zeatin and decreases in the senescence-inducing ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC) in the leaves. Thus, cwInv critically functions at the integration point of metabolic, hormonal, and stress signals, providing a novel strategy to overcome drought-induced limitations to crop yield, without negatively affecting plant fitness under optimal growth conditions.


Assuntos
Parede Celular/enzimologia , Chenopodium/genética , Secas , Expressão Ectópica do Gene , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Solanum lycopersicum/fisiologia , beta-Frutofuranosidase/genética , Chenopodium/metabolismo , Solanum lycopersicum/enzimologia , Solanum lycopersicum/genética , Fotossíntese , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , beta-Frutofuranosidase/metabolismo
20.
J Opt Soc Am A Opt Image Sci Vis ; 32(10): 1791-6, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26479932

RESUMO

In this paper, we describe analytically the propagation of Airy-type pulses truncated by a finite-time aperture when second- and third-order dispersion effects are considered. The mathematical method presented here, which is based on the superposition of exponentially truncated Airy pulses, is very effective and allows us to avoid the use of time-consuming numerical simulations. We analyze the behavior of the time-truncated ideal Airy pulse and also the interesting case of a time-truncated Airy pulse with a "defect" in its initial profile, which reveals the self-healing property of this kind of pulse solution.

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