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1.
Future Oncol ; 19(12): 863-872, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37194701

RESUMO

Renal cell carcinoma (RCC) management has seen a revolution over the last decades. Six Lebanese oncologists discussed recent updates in RCC management and outlined the challenges and future directions in Lebanon. Sunitinib continues to be a first-line choice for metastatic RCC in Lebanon, except for intermediate- and poor-risk patients. Immunotherapy is not always accessible to patients or selected routinely as first-line therapy. More data are needed on the sequencing of immunotherapy and tyrosine kinase inhibitor treatments and on the use of immunotherapy beyond progression and/or after failure of immunotherapy in the first-line setting. For second-line management, the clinical experience with axitinib for low tumor growth rate and nivolumab after progression on tyrosine kinase inhibitors make those two agents the most widely used. Several challenges affect the Lebanese practice, limiting the accessibility and availability of the medications. Reimbursement remains the most critical challenge, especially with the socioeconomic crisis of October 2019.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/patologia , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/patologia , Sunitinibe/uso terapêutico , Axitinibe/uso terapêutico , Nivolumabe/uso terapêutico
2.
J Chem Phys ; 158(15)2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37094001

RESUMO

We develop an improved stochastic formalism for the Bethe-Salpeter equation (BSE), based on an exact separation of the effective-interaction W into two parts, W = (W - vW) + vW, where the latter is formally any translationally invariant interaction, vW(r - r'). When optimizing the fit of the exchange kernel vW to W, using a stochastic sampling W, the difference W - vW becomes quite small. Then, in the main BSE routine, this small difference is stochastically sampled. The number of stochastic samples needed for an accurate spectrum is then largely independent of system size. While the method is formally cubic in scaling, the scaling prefactor is small due to the constant number of stochastic orbitals needed for sampling W.

3.
Neurosurg Rev ; 46(1): 146, 2023 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-37354243

RESUMO

Cranial irradiation is associated with several adverse events such as endocrinopathy, growth retardation, neurocognitive impairment, secondary malignancies, cerebral vasculopathy, and potential stroke. The better side effects profile of proton beam therapy compared with that of photon radiation therapy is due to its physical properties, mainly the sharp dose fall-off after energy deposition in the Bragg peak. Despite the better toxicity profile of proton beam therapy, the risk of  moyamoya syndrome still exists. We conducted a systematic review of the existing literature on moyamoya syndrome after receiving cranial radiation therapy for pediatric brain tumors to investigate the incidence of moyamoya syndrome after receiving photon versus proton radiation therapy. In this review, we report that the incidence of moyamoya syndrome after receiving proton beam therapy is almost double that of photon-induced moyamoya syndrome. Patients who received proton beam therapy for the management of pediatric brain tumors are more likely to develop moyamoya syndrome at the age of less than 5 years. Meanwhile, most patients with proton-induced moyamoya are more likely to be diagnosed within the first 2 years after the completion of their proton beam therapy.


Assuntos
Neoplasias Encefálicas , Doença de Moyamoya , Terapia com Prótons , Criança , Humanos , Pré-Escolar , Terapia com Prótons/efeitos adversos , Doença de Moyamoya/epidemiologia , Doença de Moyamoya/etiologia , Prótons , Incidência , Neoplasias Encefálicas/complicações
4.
Chem Biodivers ; 20(9): e202300778, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37599265

RESUMO

Our study aimed to test the potential of Citrus oils in protecting against paracetamol (PAR)-induced hepatotoxicity. The essential oils of Pineapple sweet orange (OO), Murcott mandarin (MO), Red grapefruit (GO), and Oval kumquat (KO) were investigated using gas chromatography coupled with mass spectrometry (GC/MS). Twenty-seven compounds were identified, with monoterpene hydrocarbons being abundant class. d-Limonene had the highest percentage (92.98 %, 92.82 %, 89.75 %, and 94.46 % in OO, MO, GO, and KO, respectively). Hierarchical cluster analysis (HCA) and principal components analysis (PCA) revealed that octanal, linalool, germacrene D, and d-limonene were the principal discriminatory metabolites that segregated the samples into three distinct clusters. In vitro antioxidant capacities were ranged from 1.2-12.27, 1.79-5.91, and 235.05-585.28 µM Trolox eq/mg oil for 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic (ABTS), ferric-reducing antioxidant power (FRAP), and oxygen radical absorbance capacity (ORAC), respectively. In vivo, citrus oils exhibited a significant reduction in alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), and nitric oxide (NO). Additionally, there was an increase in glutathione reductase (GSH), and the liver architecture was nearly normal. Molecular docking revealed that d-limonene exhibited a good inhibitory interaction with cytochrome P450 (CYP450) isoforms 1A2, 3A4, and 2E1, with binding energies of -6.17, -4.51, and -5.61 kcal/mol, respectively.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Citrus , Óleos Voláteis , Óleos Voláteis/química , Citrus/química , Antioxidantes/química , Acetaminofen , Limoneno , Interações Ervas-Drogas , Simulação de Acoplamento Molecular
5.
Sensors (Basel) ; 23(3)2023 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-36772320

RESUMO

The use of artificial intelligence to automate PV module fault detection, diagnosis, and classification processes has gained interest for PV solar plants maintenance planning and reduction in expensive inspection and shutdown periods. The present article reports on the development of an adaptive neuro-fuzzy inference system (ANFIS) for PV fault classification based on statistical and mathematical features extracted from outdoor infrared thermography (IRT) and I-V measurements of thin-film PV modules. The selection of the membership function is shown to be essential to obtain a high classifier performance. Principal components analysis (PCA) is used to reduce the dimensions to speed up the classification process. For each type of fault, effective features that are highly correlated to the PV module's operating power ratio are identified. Evaluation of the proposed methodology, based on datasets gathered from a typical PV plant, reveals that features extraction methods based on mathematical parameters and I-V measurements provide a 100% classification accuracy. On the other hand, features extraction based on statistical factors provides 83.33% accuracy. A novel technique is proposed for developing a correlation matrix between the PV operating power ratio and the effective features extracted online from infrared thermal images. This eliminates the need for offline I-V measurements to estimate the operating power ratio of PV modules.

6.
Nano Lett ; 22(8): 3196-3203, 2022 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-35404606

RESUMO

A resonant microcantilever sensor is fabricated from a zinc oxide (ZnO) thin film, which serves as both the structural and sensing layers. An open-air spatial atomic layer deposition technique is used to deposit the ZnO layer to achieve a ∼200 nm thickness, an order of magnitude lower than the thicknesses of conventional microcantilever sensors. The reduction in the number of layers, in the cantilever dimensions, and its overall lower mass lead to an ultrahigh sensitivity, demonstrated by detection of low humidity levels. A maximum sensitivity of 23649 ppm/% RH at 5.8% RH is observed, which is several orders of magnitude larger than those reported for other resonant humidity sensors. Furthermore, the ZnO cantilever sensor is self-actuated in air, an advantageous detection mode that enables simpler and lower-power-consumption sensors.


Assuntos
Óxido de Zinco , Umidade , Óxido de Zinco/química
7.
Inflammopharmacology ; 31(2): 859-875, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36773191

RESUMO

In this study, the anti-inflammatory effects of the methanolic extract (TE) of Plumeria obtusa L. (aerial parts) and its fractions were evaluated in vitro, and active fraction was evaluated in vivo. Among tested extracts, dichloromethane fraction (DCM-F) exhibited the strongest inhibition of lipopolysaccharide (LPS)-induced nitric oxide (NO) in RAW 264.7 macrophages. The effect of DCM-F on LPS-induced acute lung injury (ALI) in mice was studied. The animals were divided into five groups (n = 7) randomly; Gp I: negative control, GP II: positive control (LPS group), GP III: standard (dexamethasone, 2 mg/kg b.wt), GP IV and V: DCM-F (100 mg/kg), and DEM-F (200 mg/kg), respectively. DCM-F at a dose of 200 mg/kg suppressed the ability of LPS to increase the levels of nitric oxide synthase (iNOS), NO, tumor necrosis factor-α (TNF-α), and interleukin 6 (IL-6), as measured by ELISA. In addition, the expression of cyclooxygenase-2 (COX-2) was reduced (determined by immunohistochemistry) and the level of malondialdehyde (MDA) was decreased while that of catalase was restored to the normal values. Furthermore, the histopathological scores of inflammation induced by LPS were reduced. Twenty-two compounds were tentatively identified in DCM-F using LC/ESI-QToF with iridoids, phenolic derivatives and flavonoids as major constituents. Identified compounds were subjected to two different molecular docking processes against iNOS and prostaglandin E synthase-1 target receptors. Notably, protoplumericin A and 13-O-coumaroyl plumeride were the most promising members compared to the co-crystallized inhibitor in each case. These findings suggested that DCM-F attenuates the LPS-induced ALI in experimental animals through its anti-inflammatory and antioxidant potential.


Assuntos
Lesão Pulmonar Aguda , Lipopolissacarídeos , Camundongos , Animais , Lipopolissacarídeos/farmacologia , Simulação de Acoplamento Molecular , Extratos Vegetais/uso terapêutico , NF-kappa B/metabolismo , Inflamação/metabolismo , Macrófagos , Anti-Inflamatórios/uso terapêutico , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/metabolismo , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo
8.
J Med Virol ; 93(12): 6512-6518, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34241912

RESUMO

There is a great demand for more rapid tests for SARS-CoV-2 detection to reduce waiting time, boost public health strategies for combating disease, decrease costs, and prevent overwhelming laboratory capacities. This study was conducted to assess the performance of 10 lateral flow device viral antigen immunoassays for the detection of SARS-CoV-2 in nasopharyngeal swab specimens. We analyzed 231 nasopharyngeal samples collected from October 2020 to December 2020, from suspected COVID-19 cases and contacts of positive cases at Biotechnology Research Center laboratories, Tripoli, Libya. The performance of 10 COVID-19 Antigen (Ag) rapid test devices for the detection of SARS-CoV-2 antigen was compared to a quantitative reverse transcription-polymerase chain reaction (RT-qPCR). In this study, 161 cases had symptoms consistent with COVID-19. The mean duration from symptom onset was 6.6 ± 4.3 days. The median cycle threshold (Ct ) of positive samples was 25. Among the 108 positive samples detected by RT-qPCR, the COVID-19 antigen (Ag) tests detected 83 cases correctly. All rapid Ag test devices used in this study showed 100% specificity. While tests from six manufacturers had an overall sensitivity range from 75% to 100%, the remaining four tests had a sensitivity of 50%-71.43%. Sensitivity during the first 6 days of symptoms and in samples with high viral loads (Ct < 25), was 100% in all but two of the test platforms. False-negative samples had a median Ct of 34 and an average duration of onset of symptoms of 11.3 days (range = 5-20 days). Antigen test diagnosis has high sensitivity and specificity in early disease when patients present less than 7 days of symptom onset. Patients are encouraged to test as soon as they get COVID-19-related symptoms within 1 week and to seek medical advice within 24 h if they develop disturbed smell/taste. The use of rapid antigen tests is important for controlling the COVID-19 pandemic and reducing the burden on molecular diagnostic laboratories.


Assuntos
Antígenos Virais/análise , Teste Sorológico para COVID-19/métodos , COVID-19/diagnóstico , Imunoensaio/métodos , Adulto , Teste Sorológico para COVID-19/economia , Reações Falso-Negativas , Feminino , Humanos , Imunoensaio/economia , Masculino , Nasofaringe/virologia , Estudos Prospectivos , SARS-CoV-2/imunologia , Sensibilidade e Especificidade , Fatores de Tempo , Carga Viral
9.
Psychol Health Med ; 26(9): 1134-1142, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33251848

RESUMO

Depression and anxiety are the most common mood disorder among end-stage renal disease (ESRD) patients, which can negatively affect quality-of-life and treatment outcomes. This study aimed to estimate the prevalence of depression and anxiety symptoms among ESRD patients undergoing hemodialysis (HD) and test associations with several covariates. In across-sectional study, we collected data from 457 patients using Hospital Anxiety and Depression Scale (HADS). We used multinomial logistic regression to model the associations between depression/anxiety symptoms and several covariates. The prevalence of depression (anxiety) symptoms was 21.7%(21.4%). About 12.6% had both depression and anxiety. Males were significantly less likely to have anxiety (depression) compared to females. Married with children were significantly less likely to have anxiety compared to divorced/widowed. Patients with Glomerulonephritis were significantly more likely to have anxiety (depression) compared to other causes of dialysis. Depression and anxiety are prevalent among HD patients with their HADS scores significantly positively correlated. This requires regular screening for symptoms of anxiety/depression. Future interventions should target females, those on dialysis between one and three years, and those with glomerulonephritis as ESRD cause. Finally, HADS is ascreening tool for symptoms of anxiety and depression for which aspecialist should assess the definitive diagnosis clinically.


Assuntos
Ansiedade , Depressão , Falência Renal Crônica , Ansiedade/epidemiologia , Depressão/epidemiologia , Feminino , Humanos , Falência Renal Crônica/psicologia , Falência Renal Crônica/terapia , Masculino , Prevalência , Diálise Renal
10.
World J Urol ; 38(3): 681-693, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31297628

RESUMO

PURPOSE: Prostate cancer care in the Middle East is highly variable and access to specialist multidisciplinary management is limited. Academic tertiary referral centers offer cutting-edge diagnosis and treatment; however, in many parts of the region, patients are managed by non-specialists with limited resources. Due to many factors including lack of awareness and lack of prostate-specific antigen (PSA) screening, a high percentage of men present with locally advanced and metastatic prostate cancer at diagnosis. The aim of these recommendations is to assist clinicians in managing patients with different levels of access to diagnostic and treatment modalities. METHODS: The first Advanced Prostate Cancer Consensus Conference (APCCC) satellite meeting for the Middle East was held in Beirut, Lebanon, November 2017. During this meeting a consortium of urologists, medical oncologists, radiation oncologist and imaging specialists practicing in Lebanon, Syria, Iraq, Kuwait and Saudi Arabia voted on a selection of consensus questions. An additional workshop to formulate resource-stratified consensus recommendations was held in March 2019. RESULTS: Variations in practice based on available resources have been proposed to form resource-stratified recommendations for imaging at diagnosis, initial management of localized prostate cancer requiring therapy, treatment of castration-sensitive/naïve advanced prostate cancer and treatment of castration-resistant prostate cancer. CONCLUSION: This is the first regional consensus on prostate cancer management from the Middle East. The following recommendations will be useful to urologists and oncologists practicing in all areas with limited access to specialist multi-disciplinary teams, diagnostic modalities and treatment resources.


Assuntos
Antagonistas de Androgênios/uso terapêutico , Antineoplásicos Hormonais/uso terapêutico , Recursos em Saúde , Acessibilidade aos Serviços de Saúde , Prostatectomia , Neoplasias da Próstata/terapia , Radioterapia Adjuvante , Acetato de Abiraterona/uso terapêutico , Antineoplásicos/uso terapêutico , Benzamidas , Biópsia com Agulha de Grande Calibre , Neoplasias Ósseas/secundário , Neoplasias Ósseas/terapia , Docetaxel/uso terapêutico , Endossonografia , Humanos , Iraque , Calicreínas/metabolismo , Kuweit , Líbano , Excisão de Linfonodo , Imageamento por Ressonância Magnética , Masculino , Margens de Excisão , Oriente Médio , Metástase Neoplásica , Nitrilas , Feniltioidantoína/análogos & derivados , Feniltioidantoína/uso terapêutico , Tomografia por Emissão de Pósitrons , Antígeno Prostático Específico/metabolismo , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/patologia , Neoplasias de Próstata Resistentes à Castração/diagnóstico , Neoplasias de Próstata Resistentes à Castração/epidemiologia , Neoplasias de Próstata Resistentes à Castração/patologia , Neoplasias de Próstata Resistentes à Castração/terapia , Risco , Terapia de Salvação , Arábia Saudita , Síria
11.
Small ; 15(46): e1904415, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31577386

RESUMO

Herein, the previously unrealized ability to grow nanorods and nanotubes of 2D materials using femtosecond laser irradiation is demonstrated. In as short as 20 min, nanorods of tungsten disulfide, molybdenum disulfide, graphene, and boron nitride are grown in solutions. The technique fragments nanoparticles of the 2D materials from bulk flakes and leverages molecular scale alignment by nonresonant intense laser pulses to direct their assembly into nanorods up to several micrometers in length. The laser treatment process is found to induce phase transformations in some of the materials, and also results in the modification of the nanorods with functional groups from the solvent atoms. Notably, the WS2 nanoparticles, which are ablated from semiconducting 2H WS2 crystallographic phase flakes, reassemble into nanorods consisting of the 1T metallic phase. Due to this transition, and the 1D nature of the fabricated nanorods, the WS2 nanorods display substantial improvements in electrical conductivity and optical transparency when employed as transparent conductors.

12.
Behav Brain Funct ; 11: 7, 2015 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-25888881

RESUMO

BACKGROUND: Diabetes Mellitus (DM) is associated with pathological changes in the central nervous system (CNS) and alterations in oxidative stress. The aim of this study was to determine whether dietary supplement with whey protein (WP) could improve neurobehavior, oxidative stress and neuronal structure in the CNS. METHODS: Animals were distributed in three groups, a control group (N), a diabetic mellitus group (DM) and a DM group orally supplemented with WP (WP). RESULTS: The DM group of animals receiving WP had reduced blood glucose, significantly decreased free radical Diphenyl-picrylhydrazyl (DPPH) and lower lipid peroxidation in brain tissue. The WP group of animals showed improvement in balancing, coordination and fore-limb strength, oxidative stress and neuronal structure. CONCLUSION: The results of this study show that dietary supplementation with WP reduced oxidative stress, protected CNS neurons and improved the neurobehavior of diabetic mice.


Assuntos
Comportamento Animal/efeitos dos fármacos , Química Encefálica/efeitos dos fármacos , Diabetes Mellitus Experimental/psicologia , Fármacos Neuroprotetores/farmacologia , Proteínas do Soro do Leite/farmacologia , Animais , Compostos de Bifenilo/metabolismo , Glicemia/metabolismo , Encéfalo/patologia , Camelus , Diabetes Mellitus Experimental/patologia , Força da Mão , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Camundongos , Atividade Motora/efeitos dos fármacos , Oxirredução , Picratos/metabolismo
13.
Int J Syst Evol Microbiol ; 65(Pt 4): 1335-1341, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25667396

RESUMO

A re-evaluation of the taxonomic position of two strains, 1383(T) and 2249, isolated from poppy seeds and tea leaves, which had been identified as Siccibacter turicensis (formerly Cronobacter zurichensis ), was carried out. The analysis included phenotypic characterization, 16S rRNA gene sequencing, multilocus sequence analysis (MLSA) of five housekeeping genes (atpD, fusA, glnS, gyrB and infB; 2034 bp) and ribosomal MLSA (53 loci; 22 511 bp). 16S rRNA gene sequence analysis and MLSA showed that the strains formed an independent phylogenetic lineage, with Siccibacter turicensis LMG 23730(T) as the closest neighbour. Average nucleotide identity analysis and phenotypic analysis confirmed that these strains represent a novel species, for which the name Siccibacter colletis sp. nov. is proposed. The type strain is 1383(T) ( = NCTC 14934(T) = CECT 8567(T) = LMG 28204(T)). An emended description of Siccibacter turicensis is also provided.


Assuntos
Camellia sinensis/microbiologia , Enterobacteriaceae/classificação , Papaver/microbiologia , Filogenia , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Enterobacteriaceae/genética , Enterobacteriaceae/isolamento & purificação , Genes Bacterianos , Dados de Sequência Molecular , Tipagem de Sequências Multilocus , Hibridização de Ácido Nucleico , Folhas de Planta/microbiologia , RNA Ribossômico 16S/genética , Sementes/microbiologia , Análise de Sequência de DNA
14.
J Chem Theory Comput ; 20(2): 551-557, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38175913

RESUMO

Calculations of excited states in the Green's function formalism often invokes the diagonal approximation, in which the quasiparticle states are taken from a mean-field calculation. In this paper, we extend the stochastic approaches applied in the many-body perturbation theory and overcome this limitation for large systems in which we are interested in a small subset of states. We separate the problem into a core subspace whose coupling to the remainder of the system environment is stochastically sampled. This method is exemplified on computing hole injection energies into CO2 on an extended gold surface with nearly 3000 electrons. We find that in the extended system the size of the problem can be compressed up to 95% using stochastic sampling. This result provides a way forward for self-consistent stochastic methods and determination of Dyson orbitals in large systems.

15.
J Chem Theory Comput ; 20(10): 4196-4204, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38713513

RESUMO

We extend our recently developed sparse-stochastic fragmented exchange formalism for ground-state near-gap hybrid DFT to calculate absorption spectra within linear-response time-dependent generalized Kohn-Sham DFT (LR-GKS-TDDFT) for systems consisting of thousands of valence electrons within a grid-based/plane-wave representation. A mixed deterministic/fragmented-stochastic compression of the exchange kernel, here using long-range explicit exchange functionals, provides an efficient method for accurate optical spectra. Both real-time propagation as well as frequency-resolved Casida-equation-type approaches for spectra are presented, and the method is applied to large molecular dyes.

16.
Genes (Basel) ; 15(10)2024 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-39457406

RESUMO

Cronobacter sakazakii is associated with the ingestion of contaminated reconstituted powdered infant formula (PIF), resulting in necrotizing enterocolitis, sepsis and meningitis in neonatal infants. Potential virulence determinants include the variable capsular polysaccharides; K-antigen and colanic acid (CA). Strains encoding for the capsule variant K2:CA2 have been strongly associated with neonatal meningitis cases. This study aimed to develop and apply a multiplex PCR assay to determine C. sakazakii K-antigen and colanic acid types. Twenty-six strains of C. sakazakii which had previously been isolated from food and environmental sources were used. These cover 18 multilocus sequence types and four serotypes. Based on our research findings, we have identified two K-antigen types present. Specifically, the K1-antigen was observed in sequence types ST1, ST8, ST20, ST23, ST64, ST198, ST263, ST264 and ST406, while the K2-antigen was present in ST4, ST9, ST12, ST13, ST136, ST233, ST245 and ST405. Additionally, we detected colanic acid (CA) type 1 in sequence types ST1, ST8, ST9, ST20, ST245 and ST405, and colanic acid (CA) type 2 in ST4, ST12, ST13, ST23, and ST64. We compared the predicted K-antigen and colanic acid types with the entire genome sequences of the strains. The comparison showed complete agreement between the PCR amplification results and the genomic analysis of the K-antigen and colanic acid-encoding regions. This assay is a useful tool for rapid identification of C. sakazakii, K-antigen and colanic acid types, in routine diagnoses and foodborne investigations. In addition, it will contribute to our knowledge of virulence factors associated with life-threatening neonatal meningitis.


Assuntos
Cápsulas Bacterianas , Cronobacter sakazakii , Cronobacter sakazakii/genética , Cronobacter sakazakii/patogenicidade , Cápsulas Bacterianas/genética , Humanos , Reação em Cadeia da Polimerase Multiplex/métodos , Antígenos de Bactérias/genética , Tipagem de Sequências Multilocus , Polissacarídeos , Microbiologia de Alimentos , Fórmulas Infantis/microbiologia , Infecções por Enterobacteriaceae/microbiologia , Lactente , Antígenos de Superfície
17.
Libyan J Med ; 19(1): 2348235, 2024 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38718270

RESUMO

Among hospitalized patients worldwide, infections caused by multidrug-resistant (MDR) bacteria are a major cause of morbidity and mortality. This study aimed to isolate MDR bacteria from five intensive care units (ICUs) at Tripoli University Hospital (TUH). A prospective cross-sectional study was conducted over a seven-month period (September 2022 to March 2023) across five ICUs at TUH. A total of 197 swabs were collected from Patients', healthcare workers' and ICUs equipment. Samples collected from patients were nasal swabs, oral cavity swabs, hand swabs, sputum specimens, skin swabs, umbilical venous catheter swabs, and around cannula. Swabs collected from health care workers were nasal swabs, whereas ICUs equipment's samples were from endotracheal tubes, oxygen masks, and neonatal incubators. Identification and antimicrobial susceptibility test was confirmed by using MicroScan auto SCAN 4 (Beckman Coulter). The most frequent strains were Gram negative bacilli 113 (57.4%) with the predominance of Acinetobacter baumannii 50/113 (44%) followed by Klebsiella pneumoniae 44/113 (40%) and Pseudomonas aeruginosa 6/113 (5.3%). The total Gram positive bacterial strains isolated were 84 (42.6%), coagulase negative Staphylococci 55 (66%) with MDRs (89%) were the most common isolates followed by Staphylococcus aureus 15 (17.8%). Different antibiotics were used against these isolates; Gram- negative isolates showed high resistance rates to ceftazidime, gentamicin, amikacin and ertapenem. A. baumannii were the most frequent MDROs (94%), and the highest resistance rates in Gram-positive strains were observed toward ampicillin, oxacillin, ampicillin/sulbactam and Cefoxitin, representing 90% of total MDR Gram-positive isolates. ESBL and MRS were identified in most of strains. The prevalence of antibiotic resistance was high for both Gram negative and Gram positive isolates. This prevalence requires strict infection prevention and control intervention, continuous monitoring, implementation of effective antibiotic stewardship, immediate, concerted and collaborative action to monitor its prevalence and spread in the hospital.


Assuntos
Farmacorresistência Bacteriana Múltipla , Hospitais Universitários , Unidades de Terapia Intensiva , Humanos , Líbia/epidemiologia , Estudos Transversais , Prevalência , Estudos Prospectivos , Masculino , Feminino , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Adulto , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Negativas/efeitos dos fármacos , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Bactérias Gram-Positivas/isolamento & purificação , Bactérias Gram-Positivas/efeitos dos fármacos , Pessoa de Meia-Idade
18.
Sci Rep ; 13(1): 8878, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37264044

RESUMO

This study aims at investigating worn surface topography and mathematical modeling of annealed Ti-6Al-3Mo-2Sn-2Zr-2Nb-1.5Cr alloy using response surface methodology (RSM). The alloy was subjected to three different regimes in order to study their effect on mechanical properties. First regime was applying cold deformation by compression until 15% drop in height at room temperature. The second regime was performing solution treated on the deformed samples at 920 °C for 15 min then air-cooled (AC) to ambient temperature. Third regime was applying aging on the deformed and solution treated specimen for 4 hr at 590 °C followed by air-cooling. Three different velocities (1, 1.5, and 2 m/s) were adopted to conduct dry sliding wear according to the experimental design technique (EDT). Gwyddion and Matlab softwares were used to detect worn surface photographs analytically and graphically. Maximum hardness of 425 HV20 was obtained for AC+Aging specimen, while minimum hardness of 353 HV20 was reported for the annealed specimen. Applying aging process after solution treatment enhanced considerably the wear property and this enhancement reached 98% as compared to the annealed condition. The relationship between input factors (hardness & velocity) and responses (Abbott Firestone zones) was demonstrated using analysis of variance (ANOVA). The best models for Abbott Firestone zones (high peaks, exploitation, and voids) produced accurate data that could be estimated for saving time and cost. The results showed that the average surface roughness increases with increasing sliding velocity for all conditions except AC+Aging condition where the average surface roughness decreased with increasing sliding velocity. The results revealed that at low velocity and hardness, the material gives the highest exploitation zone (86%). While at high velocity and hardness, the material gives the lowest exploitation zone (70%). In general, the predicted results of mathematical model showed close agreement with experimental results, creating that models could be utilized to predict Abbott Firestone zones satisfactorily.

19.
ACS Sens ; 8(4): 1630-1638, 2023 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-36926856

RESUMO

We investigate the interaction of various analytes (toluene, acetone, ethanol, and water) possessing different structures, bonding, and molecular sizes with a laser-exfoliated WS2 sensing material in a chemiresistive sensor. The sensor showed a clear response to all analytes, which was significantly enhanced by modifying the WS2 surface. This was achieved by creating WS2-ZnO heterojunctions via the deposition of ZnO nanoparticles on the WS2 surface with a high-throughput, atmospheric-pressure spatial atomic layer deposition system. Water and ethanol produced a much higher response compared to acetone and toluene for both the WS2 and WS2-ZnO sensing mediums. We resolved that the charge-asymmetry points in analyte molecules play a key role in determining the sensor response. High charge-asymmetry points correspond to highly polar bonds (HPBs) in a neutral molecule that have a high probability of interaction with the sensing medium. Our results indicate that the polarity of the HPBs primarily dictates the interaction between the analyte and sensing medium and consequently controls the response of the sensor. Moreover, the size of the analyte molecule was found to affect the sensing response; if two molecules have the same HPBs and are exposed to the same sensing medium, the smaller molecule is likely to produce a higher and faster response. Our study provides a comprehensive picture of analyte-sensor interactions that can help in advancing semiconductor gas sensors, including those based on two-dimensional materials.


Assuntos
Acetona , Óxido de Zinco , Etanol , Tolueno , Água
20.
J Chem Theory Comput ; 19(22): 7989-7997, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-37955975

RESUMO

We present a new velocity-gauge real-time, time-dependent density functional tight-binding (VG-rtTDDFTB) implementation in the open-source DFTB+ software package (https://dftbplus.org) for probing electronic excitations in large, condensed matter systems. Our VG-rtTDDFTB approach enables real-time electron dynamics simulations of large, periodic, condensed matter systems containing thousands of atoms with a favorable computational scaling as a function of system size. We provide computational details and benchmark calculations to demonstrate its accuracy and computational parallelizability on a variety of large material systems. As a representative example, we calculate laser-induced electron dynamics in a 512-atom amorphous silicon supercell to highlight the large periodic systems that can be examined with our implementation. Taken together, our VG-rtTDDFTB approach enables new electron dynamics simulations of complex systems that require large periodic supercells, such as crystal defects, complex surfaces, nanowires, and amorphous materials.

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