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1.
Acta Chir Plast ; 66(2): 73-81, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39174342

RESUMO

Reconstruction of large soft tissue foot defects were considered a difficult issue due to weight-bearing function of the foot. The reconstruction becomes more difficult when both plantar and dorsal soft tissues are involved. The options for the reconstruction were variable, in 2016 Hao Wu et al. presented a combined flap for coverage of combined fore-foot plantar and dorsal soft tissue defects. We used combined flaps in two cases and present our experience in this article.


Assuntos
Procedimentos de Cirurgia Plástica , Humanos , Masculino , Procedimentos de Cirurgia Plástica/métodos , Artérias da Tíbia/cirurgia , Retalhos de Tecido Biológico/transplante , Pessoa de Meia-Idade , Feminino , Pé/cirurgia , Traumatismos do Pé/cirurgia , Lesões dos Tecidos Moles/cirurgia , Adulto , Retalhos Cirúrgicos
2.
Anal Bioanal Chem ; 415(23): 5563-5574, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37505234

RESUMO

Heavy single-chain antibodies (VHH or nanobodies) are popular in the medical and analytical fields due to its small size, high solubility, stability, and other advantageous features. However, the usage of VHHs is limited by the low yield of its production and purification. In order to determine the optimal purification strategy for VHH to improve the yield, a method to monitor purification at the intermediate steps is needed. In this study, a simple, sensitive, low-cost sandwich enzyme-linked immunosorbent assay (ELISA) was developed to quantitate VHHs throughout the purification steps. Under optimized conditions, the assay has a sensitivity of 0.149 OD·mL/ng and a limit of detection (LOD) of 0.029 ng/mL. The average recoveries of the assay against the spiked samples were 101.9-106.0% and 100.7-108.0%. The method was applied to a variety of real samples for the detection of different VHHs in bacterial cell media. High amount of VHHs (up to 41.3 mg/mL), which are comparable to the average yield of VHH in standard production protocols, were detected in the media. This study raises attention to the problem of protein losses in cell culture supernatants and provides a method for the continuous detection of the protein abundance to optimize the expression and purification protocols especially for nanobodies.


Assuntos
Anticorpos de Cadeia Única , Anticorpos de Domínio Único , Escherichia coli/metabolismo , Hemaglutininas , Ensaio de Imunoadsorção Enzimática/métodos
3.
Chem Biodivers ; 20(11): e202301208, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37775474

RESUMO

A new monoalkyl glycerol ether, 3-(n-henicosyloxy)propane-1,2-diol (1), was isolated from the CH2 Cl2 /MeOH crude extract of the Red Sea soft coral Nephthea mollis. Additionally, three known related analogs were identified: chimyl alcohol (2), batyl alcohol (3), and 3-(icosyloxy)propane-1,2-diol (4). The chemical structure of 3-(n-henicosyloxy)propane-1,2-diol was determined using advanced spectroscopic analyses, including 1D, 2D Nuclear Magnetic Resonance (NMR), Electron Ionization mass spectra (EI-MS), and High-Resolution Electron Spray Ionization mass spectra (HR-ESI-MS) analyses. Furthermore, the identification of chimyl alcohol, batyl alcohol and 3-(icosyloxy)propane-1,2-diol was achieved by studying their EI mass fragmentation analyses and comparing their mass data with those previously reported in the literature. The cytotoxic activity of the Nephthea mollis crude extract and 3-(n-henicosyloxy)propane-1,2-diol was evaluated against five human cancer cell lines: HepG2 (hepatocellular carcinoma), MCF-7 (breast carcinoma), NCI-1299 (lung carcinoma), HeLa (cervical cancer cell), and HT-29 (colon adenocarcinoma). Moreover, 3-(n-henicosyloxy)propane-1,2-diol revealed moderate cytotoxicity against the HeLa cell lines with an IC50 value of 24.1 µM, while showing inactivity against the remaining cell lines (IC50 >100 µM).


Assuntos
Adenocarcinoma , Antozoários , Antineoplásicos , Neoplasias do Colo , Animais , Humanos , Células HeLa , Éter , Glicerol/metabolismo , Antozoários/química , Propano , Oceano Índico , Éteres de Glicerila/metabolismo , Antineoplásicos/química , Etil-Éteres/metabolismo , Éteres , Misturas Complexas/metabolismo , Linhagem Celular Tumoral
4.
Molecules ; 27(17)2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36080312

RESUMO

Root rot is one of the most significant soil and seed-borne fungal diseases, limiting the cultivation of fenugreek plants. Endophytic bacteria and their natural bioproducts have emerged as growth promoters and disease suppressors in the current era. Despite limited research, seeds are a good funder of endophytic microbiomes, which are transmitted from them to other seedling parts, thereby providing a shield against biotic and abiotic anxiety and promoting the growth at early germination and later stages. The current study evaluated the hypothesis that seed endophytic bacteria and their lytic enzymes, growth promotors, and antifungal molecules can induce growth, and inhibit root rot disease development at the same time. The isolation trial from fenugreek seeds revealed a lytic Achromobacter sp., which produces indole acetic acid, has antifungal compounds (e.g., 2-Butanol, 3,3'-oxybis-), and reduces the growth of Rhizoctonia solani by 43.75%. Under the greenhouse and natural field conditions, bacterial cells and/or supernatant improved the growth, physiology, and yield performance of fenugreek plants, and effectively suppressed the progress of root rot disease; this is the first extensive study that uses a new seed-borne endophytic bacterium as a plant-growth-promoting, and biocontrol tool against the sclerotia-forming; R. solani; the causative of fenugreek root rot.


Assuntos
Achromobacter , Trigonella , Antifúngicos/farmacologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Rhizoctonia , Sementes
5.
Molecules ; 27(18)2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36144781

RESUMO

In this study, pumice is used as a novel natural heterogeneous catalyst for the synthesis of 3,4-dihydropyrimidine-2-(1H)-ones/thiones via the one-pot multi-component condensation of aromatic aldehydes, urea/thiourea, and ethyl acetoacetate or acetylacetone in excellent yields (up to 98%). The physical and chemical properties of the catalyst were studied. Their geochemical analysis revealed a basaltic composition. Furthermore, X-ray diffraction showed that it is composed of amorphous materials with clinoptilolite and heulandites zeolite minerals in its pores. Moreover, pumice has a porosity range from 78.2-83.9% (by volume) and is characterized by a mesoporous structure (pore size range from 21.1 to 64.5 nm). Additionally, it has a pore volume between 0.00531 and 0.00781 m2/g and a surface area between 0.053 and 1.47 m2/g. The latter facilitated the reaction to proceed in a short time frame as well as in excellent yields. It is worth noting that our strategy tolerates the use of readily available, cheap, non-toxic, and thermally stable pumice catalyst. The reactions proceeded smoothly under solvent-free conditions, and products were isolated without tedious workup procedures in good yields and high purity. Indeed, pumice can be reused for at least five reuse cycles without affecting its activity.


Assuntos
Tionas , Zeolitas , Aldeídos/química , Catálise , Silicatos , Solventes , Tionas/química , Tioureia/química , Ureia/química
6.
Molecules ; 27(22)2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36432173

RESUMO

The use of pesticides leads to an increase in agricultural production but also causes harmful effects on human health when excessively used. For safe consumption, pesticide residues should be below the maximum residual limits (MRLs). In this study, the residual levels of pesticides in vegetables and fruits collected from farmers' markets in Sharkia Governorate, Egypt were investigated using LC-MS/MS and GC-MS/MS. A total number of 40 pesticides were detected in the tested vegetable and fruit samples. Insecticides were the highest group in detection frequency with 85% and 69% appearance in vegetables and fruits, respectively. Cucumber and apple samples were found to have the highest number of pesticide residues. The mean residue levels ranged from 7 to 951 µg kg-1 (in vegetable samples) and from 8 to 775 µg kg-1 (in fruit samples). It was found that 35 (40.7%) out of 86 pesticide residues detected in vegetables and 35 (38.9%) out of 90 pesticide residues detected in fruits exceeded MRLs. Results for lambda-cyhalothrin, fipronil, dimothoate, and omethoate in spinach, zucchini, kaki, and strawberry, respectively, can cause acute or chronic risks when consumed at 0.1 and 0.2 kg day-1. Therefore, it is necessary for food safety and security to continuously monitor pesticide residues in fruits and vegetables in markets.


Assuntos
Resíduos de Praguicidas , Praguicidas , Humanos , Verduras/química , Resíduos de Praguicidas/análise , Frutas/química , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Fazendeiros , Contaminação de Alimentos/análise , Praguicidas/análise
7.
Expert Syst Appl ; 204: 117410, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35502163

RESUMO

Since the advent of COVID-19, the number of deaths has increased exponentially, boosting the requirement for various research studies that may correctly diagnose the illness at an early stage. Using chest X-rays, this study presents deep learning-based algorithms for classifying patients with COVID illness, healthy controls, and pneumonia classes. Data gathering, pre-processing, feature extraction, and classification are the four primary aspects of the approach. The pictures of chest X-rays utilized in this investigation came from various publicly available databases. The pictures were filtered to increase image quality in the pre-processing stage, and the chest X-ray images were de-noised using the empirical wavelet transform (EWT). Following that, four deep learning models were used to extract features. The first two models, Inception-V3 and Resnet-50, are based on transfer learning models. The Resnet-50 is combined with a temporal convolutional neural network (TCN) to create the third model. The fourth model is our suggested RESCOVIDTCNNet model, which integrates EWT, Resnet-50, and TCN. Finally, an artificial neural network (ANN) and a support vector machine were used to classify the data (SVM). Using five-fold cross-validation for 3-class classification, our suggested RESCOVIDTCNNet achieved a 99.5 percent accuracy. Our prototype can be utilized in developing nations where radiologists are in low supply to acquire a diagnosis quickly.

8.
Ann Pharm Fr ; 80(5): 687-696, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34968477

RESUMO

New validated Spectroscopic methods were developed to assay Bromhexine Hydrochloride and its active metabolite Ambroxol Hydrochloride separately in pure form and pharmaceutical formulations. The spectrophotometric assay (method I) shows complex formation between each of the drugs and Eosin Y at 540nm at pH 3.6 and 3.4mL of 4×10-4M Eosin for Bromhexine and Ambroxol. The Spectrofluorimetric assay (method II) depends on quenching eosin native fluorescence by the studied drugs, which measured at 540nm after excitation at 302nm. The spectrophotometric absorbance-concentration plot is rectilinear over the ranges (1.0-5.0) and (1.0-10.0) µg/mL for bromhexine and ambroxol with LOD of 0.31 and 0.14µg/mL and LOQ of 0.94 and 0.42µg/mL for the two drugs respectively. The fluorometric-concentration plot is linear along the range (1.0-5.0) µg/mL and (1-10) µg/mL for the two drugs respectively with LOD of 0.13µg/mL and 0.22µg/mL and LOQ of 0.4µg/mL and 0.65µg/mL for the two drugs, respectively. Developed assays have been validated in agreement with ICH recommendations and they were used in the analysis of commercial drug formulations containing the two mucolytic drugs and the results were matching with those obtained by the comparison method.


Assuntos
Ambroxol , Bromoexina , Ambroxol/análise , Bromoexina/análise , Amarelo de Eosina-(YS) , Expectorantes/análise , Espectrofotometria/métodos
9.
Ann Clin Psychiatry ; 32(4): 239-248, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33125448

RESUMO

BACKGROUND: Magnetic seizure therapy (MST) has demonstrated fewer cognitive side effects than electroconvulsive therapy (ECT) in antidepressant efficacy trials. However, there are no effectiveness trials examining antidepressant efficacy and cognitive side effects against ECT. The aims of this study were to evaluate the comparative effectiveness of MST vs ECT in major depressive disorder (MDD), and compare the cognitive side effects of MST and ECT. METHODS: In this open-label study, patients were assigned to either ECT or high-dose MST twice a week for 5 sessions based on the clinician's and the patient's decision-making. Efficacy was primarily assessed by the Hamilton Depression Rating Scale-21 (HAMD-21); cognitive side effects were assessed by time to reorientation (TRO) and cognitive battery. RESULTS: Sixty patients were enrolled. Efficacy was similar between those assigned to MST (n = 30) and ECT (n = 30). Post-treatment HAMD-21 mean scores were 12.33 after MST, 12.80 after bitemporal (BT) ECT (n = 15), and 27.93 after right unilateral (RUL) ECT (n = 15). Magnetic seizure therapy had a significantly faster TRO of 1.8 minutes (standard deviation [SD] = 0.37) compared with ECT (RUL: 18.9 minutes [SD = 8.25]; BT: 50.2 minutes [SD = 5.89]) and had fewer cognitive side effects. CONCLUSIONS: Magnetic seizure therapy was effective for the treatment of MDD in real-world clinical care, with fewer cognitive side effects than ECT. Future studies are warranted to replicate these findings.


Assuntos
Transtorno Depressivo Maior/terapia , Estimulação Elétrica , Eletroconvulsoterapia , Fenômenos Magnéticos , Convulsões , Adulto , Cognição/efeitos dos fármacos , Feminino , Humanos , Masculino , Testes Neuropsicológicos/estatística & dados numéricos , Estudos Prospectivos , Convulsões/fisiopatologia , Resultado do Tratamento
10.
Water Environ Res ; 91(5): 428-440, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30731036

RESUMO

In Egypt, water quality (WQ) is an ordinary activity. However, the calculation of a tailor-made Egyptian WQ index is not. Therefore, this research attempts to develop an index for the agricultural drainage water (EG-DWQI) that can be reused for irrigation based on collected WQ data measured monthly from August 2000 to July 2015. The development of the EG-DWQI was carried out in four main steps, namely, parameters selection, parameter transformation to a common scale, assignment of parameters weights, and aggregation of subindices to produce a final index score. In its final form, the index can be easily estimated using a set of rating curves and their corresponding equations that were statistically tested and proved to be verified. The developed index was successfully employed to delineate the drainage WQ status that can be reused for irrigation in the Nile Delta of Egypt as benchmarking for future comparisons. The EG-DWQI is proved to be easy, fast, and does not entail complex mathematics and can be easily managed by means of a spreadsheet. PRACTITIONER POINTS: This research develops a tailor made water quality index for assessing agricultural drainage water that can be re-used for irrigation. Then, the developed index was successfully employed to delineate the water quality in the main drains located in the Nile Delta of Egypt as benchmarking for future comparisons. The application of the index is proved to be easy, fast and does not entail complicated mathematics especially with the new computer facilities.


Assuntos
Irrigação Agrícola , Reciclagem , Qualidade da Água , Egito , Purificação da Água
11.
J Chem Ecol ; 43(5): 487-492, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28477139

RESUMO

Binary and ternary combinations of volatile organic compounds identified earlier from caterpillar-infested apple foliage caught more than one thousand individuals of both sexes of several adult tortricid leafroller species in several days of trials conducted in apple orchards in southern British Columbia. A series of combinations with phenylacetonitrile, benzyl alcohol, and/or 2-phenylethanol and acetic acid enabled substantial catches of both sexes of eye-spotted budmoth, Spilonota ocellana, oblique-banded leafroller, Choristoneura rosaceana and three-lined leafroller, Pandemis limitata. These findings suggest that new monitoring aides can be developed to seasonally track populations, enabling practical applications in surveillance of female leafroller populations for the first time. It may also be possible to develop suppression tools based on combinations of kairomone compounds originally identified from leafroller larval-damaged apple trees, given the level of attraction. The discovery of these adult tortricid attractants (aromatic compounds plus acetic acid) raises new ecological questions about evolved direct plant defences against herbivores. Larval feeding-induced attraction of adult herbivores produces signals that are potentially harmful to the plant by increasing herbivory in the same family and probably feeding guild, but evidence for effects on plant fitness is needed.


Assuntos
Comportamento Animal/efeitos dos fármacos , Malus/química , Mariposas/fisiologia , Compostos Orgânicos Voláteis/farmacologia , Ácido Acético/farmacologia , Acetonitrilas/farmacologia , Animais , Álcool Benzílico/farmacologia , Feminino , Larva/crescimento & desenvolvimento , Larva/fisiologia , Masculino , Malus/metabolismo , Mariposas/efeitos dos fármacos , Compostos Orgânicos Voláteis/química
12.
J Appl Microbiol ; 120(4): 1061-73, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26834088

RESUMO

AIMS: Evaluation of the efficacy of marine lactic acid bacteria, Lactobacillus plantarum AH 78, on growth performance and immune response of Nile tilapia (Oreochromis niloticus) challenged with Aeromonas hydrophila. METHODS AND RESULTS: Marine probiotic, Lact. plantarum AH 78, was incorporated in Nile tilapia diets at 0·0, 0·5, 1·0 or 2·0% (w/w). The diets were fed to juvenile Nile tilapia for 40 days, after which they were challenged with pathogenic bacterium, Aer. hydrophila. The best growth rates and feed efficiency were obtained at 0·5% probiotic, while fish survival was not affected by dietary probiotic. After challenge with Aer. hydrophila immunological responses and survival were recorded at 1·0% probiont. Likewise, significant up-regulation of the expression of cytokine genes, IL-4, IL-12 and IFN-γ, in fish livers was found at 1·0% probiont, compared to the control diet. Concomitantly, AH 78 colonized the intestinal mucosa of treated fish, even after reverting to the control diet, and remained viable in the feed stored at 4°C up to 12 months. CONCLUSIONS: Marine Lact. plantarum AH 78 at 0·5-1·0% inclusion level conferred the best performance and immune response of Nile tilapia challenged with Aer. hydrophila. SIGNIFICANCE AND IMPACT OF THE STUDY: Marine Lact. plantarum AH 78 could be considered as a potential probiotic to control disease outbreaks in farmed Nile tilapia.


Assuntos
Ciclídeos/crescimento & desenvolvimento , Lactobacillus plantarum/fisiologia , Probióticos/farmacologia , Adolescente , Aeromonas hydrophila/fisiologia , Ração Animal/análise , Ração Animal/microbiologia , Animais , Aquicultura/métodos , Ciclídeos/imunologia , Ciclídeos/microbiologia , Citocinas/genética , Citocinas/metabolismo , Dieta , Interações Hospedeiro-Patógeno/imunologia , Humanos , Mucosa Intestinal/microbiologia , Probióticos/isolamento & purificação , Regulação para Cima
13.
Biochemistry (Mosc) ; 81(10): 1173-1181, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27908241

RESUMO

L-asparaginase (EC 3.5.1.1), which catalyzes the deamidation of L-asparagine to L-aspartic acid and ammonia, has been widely used as a key therapeutic tool in the treatment of tumors. The current commercially available L-asparaginases, produced from bacteria, have signs of toxicity and hypersensitivity reactions during the course of tumor therapy. Therefore, searching for L-asparaginases with unique biochemical properties and fewer adverse effects was the objective of this work. In this study, cyanobacterial strain Synechococcus elongatus PCC6803 was found as a novel source of L-asparaginase. The L-asparaginase gene coding sequence (gi:939195038) was cloned and expressed in E. coli BL21(DE3), and the recombinant protein (Se.ASPII) was purified by affinity chromatography. The enzyme has high affinity towards L-asparagine and shows very weak affinity towards L-glutamine. The enzymatic properties of the recombinant enzyme were investigated, and the kinetic parameters (Km, Vmax) were measured. The pH and temperature dependence profiles of the novel enzyme were analyzed. The work was extended to measure the antitumor properties of the novel enzyme against different human tumor cell lines.


Assuntos
Antineoplásicos , Asparaginase , Proteínas de Bactérias , Synechococcus , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Asparaginase/biossíntese , Asparaginase/genética , Asparaginase/isolamento & purificação , Asparaginase/farmacologia , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/farmacologia , Clonagem Molecular , Células Hep G2 , Humanos , Células MCF-7 , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/farmacologia , Synechococcus/enzimologia , Synechococcus/genética
14.
Pestic Biochem Physiol ; 128: 30-6, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26969437

RESUMO

Juvenile hormone analog (JHA) insecticides are biological and structural mimics of JH, a key insect developmental hormone. Toxic and anti-developmental effects of the JHA insecticides methoprene, fenoxycarb, and pyriproxyfen were investigated on the larval and pupal stages of Spodoptera littoralis and Spodoptera frugiperda. Bioassays showed that fenoxycarb has the highest toxicity and fastest speed of kill in 2nd instar S. littoralis. All three JHAs affected the development of 6th instar (i.e., final instar) and pupal S. frugiperda. JH esterase (JHE) is a critical enzyme that helps to regulate JH levels during insect development. JHE activity in the last instar S. littoralis and S. frugiperda was 11 and 23 nmol min(-1) ml(-1) hemolymph, respectively. Methoprene and pyriproxyfen showed poor inhibition of JHE activity from these insects, whereas fenoxycarb showed stronger inhibition. The inhibitory activity of fenoxycarb, however, was more than 1000-fold lower than that of OTFP, a highly potent inhibitor of JHEs. Surprisingly, topical application of methoprene, fenoxycarb or pyriproxyfen on 6th instars of S. littoralis and S. frugiperda prevented the dramatic reduction in JHE activity that was found in control insects. Our findings suggest that JHAs may function as JH agonists that play a disruptive role or a hormonal replacement role in S. littoralis and S. frugiperda.


Assuntos
Inseticidas/farmacologia , Hormônios Juvenis/farmacologia , Larva/efeitos dos fármacos , Spodoptera/crescimento & desenvolvimento , Animais , Hidrolases de Éster Carboxílico/metabolismo , Larva/crescimento & desenvolvimento
15.
Rev Sci Tech ; 35(3): 905-911, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28332641

RESUMO

The newly identified Middle East respiratory syndrome coronavirus (MERS-CoV), which causes severe respiratory disease, particularly in people with comorbidities, requires further investigation. Studies in Qatar and elsewhere have provided evidence that dromedary camels are a reservoir for the virus, but the exact modes of transmission of MERS-CoV to humans remain unclear. In February 2014, an assessment was made of the suitability and sensitivity of different types of sample for the detection of MERSCoV by real-time reverse-transcription polymerase chain reaction (RT-PCR) for three gene targets: UpE (upstream of the E gene), the N (nucleocapsid) gene and open reading frame (ORF) 1a. Fifty-three animals presented for slaughter were sampled. A high percentage of the sampled camels (79% [95% confidence interval 66.9-91.5%, standard error 0.0625]; 42 out of 53) were shown to be shedding MERS-CoV at the time of slaughter, yet all the animals were apparently healthy. Among the virus-positive animals, nasal swabs were most often positive (97.6%). Oral swabs were the second most frequently positive (35.7%), followed by rectal swabs (28.5%). In addition, the highest viral load, expressed as a cycle threshold (Ct) value of 11.27, was obtained from a nasal swab. These findings lead to the conclusion that nasal swabs are the candidate sample of choice for detecting MERS-CoV using RT-PCR technology in apparently healthy camels.


Des travaux de recherche approfondis sont encore nécessaires concernant le coronavirus responsable du syndrome respiratoire du Moyen-Orient (MERSCoV), un virus identifié récemment et qui provoque des troubles respiratoires sévères en particulier chez les individus atteints de pathologies multiples. Les études effectuées au Qatar et ailleurs ont démontré que les dromadaires font office de réservoirs du virus ; toutefois, les modalités précises de la transmission du MERS-CoV à l'être humain demeurent obscures. En février 2014, une équipe de chercheurs a évalué l'adéquation et la sensibilité de plusieurs types d'échantillons pour détecter le MERS-CoV en utilisant l'amplification en chaîne par polymérase couplée à une transcription inverse en temps réel (RT-PCR) spécifique pour trois cibles génétiques, à savoir la séquence UpE (en amont du gène E), le gène N (nucléocapside) et le cadre de lecture ORF1a. Pour ce faire, divers prélèvements ont été effectués sur 53 dromadaires destinés à l'abattage. Un fort pourcentage de ces dromadaires (79 % [intervalle de confiance à 95 % compris entre 66,9 et 91,5 %, erreur standard : 0,0625], soit 42 sur 53) excrétaient le MERSCoV au moment de l'abattage, mais aucun ne présentait le moindre signe clinique. Les échantillons dans lesquels le plus de cas positifs ont été détectés étaient les écouvillons nasaux (97,6 %). Venaient ensuite les écouvillons oraux, qui ont détecté 35,7 % de cas positifs, puis les écouvillons rectaux (28,5 % de cas positifs détectés). Par ailleurs, ce sont les écouvillons nasaux qui ont permis d'obtenir l'intensité la plus élevée de la réponse de la RT-PCR, exprimée en une valeur du seuil de cycles de 11,27. Ces résultats permettent de conclure que les écouvillons nasaux sont les échantillons à privilégier pour la détection du MERS-CoV par RTPCR chez les dromadaires asymptomatiques.


Es preciso investigar más a fondo el coronavirus del síndrome respiratorio de Oriente Medio (MERS-CoV), recién identificado, que provoca una grave enfermedad respiratoria, sobre todo en personas con afecciones concomitantes. Estudios realizados en Qatar y otros lugares han deparado pruebas de que los dromedarios son un reservorio del virus, pero aún no están del todo claros los modelos exactos de transmisión del MERS-CoV al ser humano. Los autores describen un análisis realizado en febrero de 2014 de la idoneidad y sensibilidad de distintos tipos de muestra para detectar el MERS-CoV mediante una reacción en cadena de la polimerasa acoplada a transcripción inversa en tiempo real (RTPCR) dirigida contra tres genes: el gen UpE (upstream of the E gene: en dirección 5' desde el gen E); el gen N (nucleocápside) y el marco de lectura abierto (ORF) 1a. Para ello se tomaron muestras de 53 animales enviados al sacrificio. Se comprobó que un elevado porcentaje de los dromedarios analizados (un 79% [intervalo de confianza al 95%: 66,9­91,5%; error estándar: 0,0625], esto es, 42 de 53) excretaban virus en el momento del sacrificio, pese a que todos los animales parecían estar sanos. Entre los ejemplares positivos para el MERS-CoV, las muestras que con más frecuencia arrojaban resultado positivo eran los frotis nasales (97,6%). Las segundas, por orden de frecuencia, eran los frotis bucales (35,7%), seguidos de los frotis rectales (28,5%). Además, la carga viral más alta, expresada por un valor de ciclo umbral (Ct) (o punto de cruce) de 11,27, se obtuvo a partir de un frotis nasal. Estos resultados llevan a la conclusión de que los frotis nasales son el tipo de muestra más adaptado para detectar el MERS-CoV en dromedarios aparentemente sanos mediante la técnica de RT-PCR.


Assuntos
Camelus , Infecções por Coronavirus/veterinária , Coronavírus da Síndrome Respiratória do Oriente Médio/isolamento & purificação , Fatores Etários , Animais , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Reservatórios de Doenças , Humanos , Coronavírus da Síndrome Respiratória do Oriente Médio/genética , Boca/virologia , Mucosa Nasal/virologia , Roupa de Proteção , Catar/epidemiologia , RNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Reto/virologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Fatores de Risco , Carga Viral/veterinária , Eliminação de Partículas Virais
16.
Environ Monit Assess ; 188(10): 580, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27660211

RESUMO

Increases in human activity have resulted in enhanced anthropogenic inputs of nitrogen (N) and carbon (C) into the Nile River. The Damietta Branch of the Nile is subject to inputs from industrial, agricultural, and domestic wastewater. This study investigated the distribution and seasonality of dissolved organic nitrogen (DON), dissolved organic carbon (DOC), and nutrients in the Nile Damietta Branch. Water samples were collected from 24 sites between May 2009 and February 2010. Dissolved organic nitrogen concentrations averaged 251 ± 115 µg/l, with a range of 90.2-671 µg/l, and contributed 40.8 ± 17.7 % to the total dissolved nitrogen (TDN) pool. Relative to autumn and winter, DON was a larger fraction of the TDN pool during spring and summer indicating the influence of bacterioplankton on the nitrogen cycle. Concentrations of DOC ranged from 2.23 to 11.3 mg/l with an average of 5.15 ± 2.36 mg/l, reflecting a high organic matter load from anthropogenic sources within the study area, and were highest during autumn. Higher values of biochemical oxygen demand (BOD), chemical oxygen demand (COD), DON, nitrate, and phosphate occurred downstream of the Damietta Branch and were probably due to anthropogenic inputs to the Nile from the Damietta district. A bacterial incubation experiment indicated that 52.1-95.0 % of DON was utilized by bacteria within 21 days. The decrease in DON concentration was accompanied by an increase in nitrate concentration of 54.8-87.3 %, presumably through DON mineralization. Based on these results, we recommend that water quality assessments consider DON and DOC, as their omission may result in an underestimation of the total organic matter load and impact.


Assuntos
Carbono/análise , Nitrogênio/análise , Rios/química , Agricultura , Egito , Monitoramento Ambiental/métodos , Resíduos Industriais , Ciclo do Nitrogênio , Estações do Ano , Águas Residuárias , Qualidade da Água
17.
Biosci Biotechnol Biochem ; 79(6): 997-1004, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25562396

RESUMO

Ionizing radiation and oxidizing agent like H2O2 were used to degrade chitosan (CS) and its derivatives; N-maleoylchitosan (NMCS), and N-phthaloylchitosan (NPhCS). The structure changes were detected using gel permeation chromatography (GPC). The results revealed that ionizing radiation degraded CS, MNCS, NPhCS and altered their molecular weights and antioxidant activity. The higher the irradiation dose, the lower the molecular weight and the higher antioxidant activity. The addition of irradiated CS and NMCS to minced chicken resulted in highly significant reduction in malondialdehyde (MDA) content (50 and 70%, respectively) if compared with the control. The irradiated NMCS toxicity study did not show strong proliferative effect at small concentrations or cytotoxic effects at higher concentrations. The obtained results suggested that CS and NMCS could be used as natural antioxidant for improving the oxidative deterioration of minced chicken during refrigerated storage.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Galinhas , Quitosana/química , Quitosana/farmacologia , Manipulação de Alimentos , Raios gama , Animais , Células CACO-2 , Quitosana/análogos & derivados , Armazenamento de Alimentos , Humanos , Oxirredução , Solubilidade , Água/química
18.
J Water Health ; 13(4): 1060-72, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26608768

RESUMO

Algal blooms at the major water treatment plants in Egypt have been reported since 2006. While previous studies focused on algal types and their correlation with disinfection by-products, correlation between raw water quality and algal blooms were not explored. Therefore, a survey of Nile water quality parameters at a major water intake in the Greater Cairo Urban Region was conducted from December 2011 to November 2012. Bench-scale experiments were conducted to evaluate the effectiveness of the conventional chloride/alum treatment compared with combined Cl/permanganate pre-oxidation with Al and Fe coagulants during the outbreak period. Addition of permanganate (0.5 mg/L) significantly reduced the chlorine demand from 5.5 to 2.7 mg/L. The applied alum coagulant dose was slightly reduced while residual Al was reduced by 27% and the algal count by 50% in the final treated waters. Applying ferric chloride and ferric sulfate as coagulants to waters treated with the combined pre-oxidation procedure effectively reduced algal count by 60% and better the total organic carbon reduction and residual aluminum in the treated water. Multivariate statistical analysis was used to identify the relationship between water quality parameters and occurrence of algae and to explain the impact of coagulants on the final water quality.


Assuntos
Água Potável/análise , Eutrofização , Purificação da Água/métodos , Qualidade da Água , Egito , Análise Multivariada , Estações do Ano
19.
Eur J Orthop Surg Traumatol ; 25(3): 543-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25269392

RESUMO

PURPOSE: The purpose of this study was to evaluate the effects of platelet-rich plasma (PRP) on distraction osteogenesis. MATERIALS AND METHODS: Tibias of 36 New Zealand white rabbits were distracted at a rate of 0.25 mm/8 h for 20 days with a circular external fixator. The animals were randomly divided into a control group that did not receive PRP therapy and an experimental group, with PRP injection into the distracted area. Radiographic examinations were performed at the 10th, 20th, 30th, 40th and 50th days after end of distraction. By the 50th day after distraction, all animals were sacrificed, the external fixator was removed and the tibia was dissected. After that, each group was subdivided into two subgroups: one for pathological study and another one for mechanical study. RESULTS: Radiologic scores were statistically similar at the 10th, 20th and 30th days. However, the experimental group demonstrated higher radiologic scores at the 40th and 50th days. Histopathologic examination revealed a statistically significant higher score in the experimental group. The PRP injected group showed an improvement of their mechanical properties. CONCLUSION: The results of this study show that PRP has beneficial effects on new bone formation during distraction osteogenesis.


Assuntos
Osteogênese por Distração/métodos , Osteogênese , Plasma Rico em Plaquetas , Animais , Fixadores Externos , Coelhos , Radiografia , Distribuição Aleatória , Tíbia/citologia , Tíbia/diagnóstico por imagem , Fatores de Tempo
20.
Phys Rev Lett ; 112(11): 117602, 2014 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-24702417

RESUMO

Codeposition of two molecular species [copper phtalocyanine (CuPc, donor) and perfluoropentacene (PFP, acceptor)] on noble metal (111) surfaces leads to the self-assembly of an ordered mixed layer with a maximized donor-acceptor contact area. The main driving force behind this arrangement is assumed to be the intermolecular C-H ⋯ F hydrogen-bond interactions. Such interactions would be maximized for a coplanar molecular arrangement. However, precise measurement of molecule-substrate distances in the molecular mixture reveals significantly larger adsorption heights for PFP than for CuPc. Most surprisingly, instead of leveling to increase hydrogen-bond interactions, the height difference is enhanced in the blends as compared to the heights found in single-component CuPc and PFP layers. The increased height of PFP in mixed layers points to an overall reduced interaction with the underlying substrate, and its influence on electronic properties like the interface dipole is investigated through work function measurements.

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