Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
1.
Environ Res ; 215(Pt 1): 114079, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36030912

RESUMEN

Worldwide, due to a dearth of innovative interventions, new forms of antimicrobial resistance (AMR) are being discovered every day in clinical and environmental settings. Therefore, it is necessary to remove these contaminants directly or indirectly from the environment. Nanomicrobial-based technology employing nanomaterials with microbes is a new paradigm that finds a place in the antimicrobial crisis. Microbial entities such as phages can be used to treat antimicrobial resistance, but phage resistance is challenging and limits its applicability. Similarly, nanotechnology will not be able to selectively remove resistant strains from the environment individually. Therefore, we employ nanomicrobial-based technology that aims to fill these gaps. In the present study, polyvalent phages were isolated from wastewater with an easy-to-use modified multi-host sequential approach, characterized and conjugated with magnetite (Fe3O4) nanoparticles with the modified formulation to form nanomicrobial conjugates (NMCs). These NMCs were subjected to characterization and in vitro antibacterial studies. The results indicated a significant polyvalency of phages in the order of Caudovirales. Transmission electron microscopy (TEM) analysis of Fe3O4 nanoparticles formed by the co-precipitation method showed a particle size of 30 ± 5 nm and the selected area electron diffraction (SAED) pattern indicates a single-phase crystalline structure. To form NMCs, isolated phages (105 PFU/mL) were immobilized onto Fe3O4 nanoparticles. Further, surface modification of Fe3O4 nanoparticles enables the covalent association of phages. Biosurfactant-functionalized Fe3O4 nanoparticles (FNMCs) were found to have higher phage loading capacity, with a significant value of p < 0.0127 and a zeta potential of -22.2 mV. TEM studies and in vitro biofilm assay showed that NMCs exhibit promising antibacterial activity against various resistant bacterial strains. Pilot studies showed that NMCs can selectively eliminate up to 98.3% of AMR in wastewater. Thus, these findings indicate a synergistic effect of both phage and nanomaterial and this technology is expected to be a new lead in wastewater management.


Asunto(s)
Bacteriófagos , Antibacterianos/farmacología , Farmacorresistencia Bacteriana , Óxido Ferrosoférrico/química , Tecnología , Aguas Residuales
2.
J Pediatr Hematol Oncol ; 44(1): e77-e83, 2022 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-33710118

RESUMEN

Despite high prevalence and incidence of ß-thalassemia in Pakistan, there is very limited work on the use of hydroxyurea (HU) in thalassemia patients in the country. This is the first insight regarding genetic profiling of BCL11A and HU responses in Pakistani ß-thalassemia. It correlates single-nucleotide polymorphisms on BCL11A (rs4671393, rs766432) and HBG2 (XmnI), age at first transfusion, and ß-globin mutations with HU response in ß-thalassemia major (BTM). Of 272 patients treated with HU, 98 were complete responders, 55 partial responders, and 119 nonresponders. Our analysis shows that HU response was significantly associated with patients having IVSI-1 or CD 30 mutation (P<0.001), age at first transfusion >1 year (P<0.001), and with the presence of XmnI polymorphism (P<0.001). The single-nucleotide polymorphisms of BCL11A were more prevalent among responders, but could not show significant association with HU response (P>0.05). Cumulative effect of all 5 predicting factors through simple binary scoring indicates that the likelihood of HU response increases with the number of primary and secondary genetic modifiers (P<0.001). Predictors scoring is a pragmatic tool to foresee HU response in patients with BTM. The authors recommend a score of ≥2 for starting HU therapy in Pakistani patients with BTM.


Asunto(s)
Hidroxiurea/administración & dosificación , Polimorfismo de Nucleótido Simple , Proteínas Represoras/genética , Talasemia beta , Niño , Preescolar , Estudios Transversales , Femenino , Humanos , Masculino , Pakistán , Talasemia beta/tratamiento farmacológico , Talasemia beta/genética
3.
Materials (Basel) ; 14(21)2021 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-34771863

RESUMEN

Worldwide, bacterial resistance to beta-lactam antibiotics is the greatest challenge in public health care. To overcome the issue, metal-based nanoparticles were extensively used as an alternative to traditional antibiotics. However, their unstable nature limits their use. In the present study a very simple, environmentally friendly, one-pot synthesis method that avoids the use of organic solvents has been proposed to design stable, novel nanocomposites. Formulation was done by mixing biogenic copper oxide (CuO) nanomaterial with glycerol and phospholipids isolated from egg yolk in an appropriate ratio at optimum conditions. Characterization was done using dynamic light scattering DLS, Zeta potential, high performance liquid chromatography (HPLC), and transmission electron microscopy (TEM). Further, its antibacterial activity was evaluated against the extended-spectrum beta-lactamase strains based on zone of inhibition and minimal inhibitory concentration (MIC) indices. Results from this study have demonstrated the formulation of stable nanocomposites with a zeta potential of 34.9 mV. TEM results indicated clear dispersed particles with an average of 59.3 ± 5 nm size. Furthermore, HPLC analysis of the egg yolk extract exhibits the presence of phospholipids in the sample and has significance in terms of stability. The newly formed nanocomposite has momentous antibacterial activity with MIC 62.5 µg/mL. The results suggest that it could be a good candidate for drug delivery in terms of bactericidal therapeutic applications.

4.
Molecules ; 26(1)2021 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-33466486

RESUMEN

Cyanobacteria (blue-green microalgae) are ubiquitous, Gram-negative photoautotrophic prokaryotes. They are considered as one of the most efficient sources of bioactive secondary metabolites. More than 50% of cyanobacteria are cultivated on commercial platforms to extract bioactive compounds, which have bene shown to possess anticancer activity. The chemically diverse natural compounds or their analogues induce cytotoxicity and potentially kill a variety of cancer cells via the induction of apoptosis, or altering the activation of cell signaling, involving especially the protein kinase-C family members, cell cycle arrest, mitochondrial dysfunctions and oxidative damage. These therapeutic properties enable their use in the pharma and healthcare sectors for the betterment of future generations. This review provides a baseline overview of the anti-cancerous cyanobacterial bioactive compounds, along with recently introduced nanomaterials that could be used for the development of new anticancer drugs to build a healthy future for mankind.


Asunto(s)
Antineoplásicos/farmacología , Productos Biológicos/farmacología , Cianobacterias/metabolismo , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos/métodos , Nanopartículas/administración & dosificación , Neoplasias/tratamiento farmacológico , Cianobacterias/química , Humanos , Nanopartículas/química , Preparaciones Farmacéuticas , Nanomedicina Teranóstica
5.
Int J Nanomedicine ; 15: 2541-2553, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32368039

RESUMEN

BACKGROUND: In the emerging field of nanotechnology, copper oxide (CuO) nanomaterials are considered to be one of the most important transition metal oxides owing to its fascinating properties. Its synthesis from green chemistry principles is gaining importance as next-generation antibiotics due to its simplicity, eco-friendliness, and cost-effectiveness. In the present study, CuO nanorods (CuO NRs) were synthesized from the aqueous fruit extract of Momordica charantia and characterized using different analytical techniques. Further, the biomedical therapeutic potential was evaluated against multi-drug resistant microbial strains. MATERIALS AND METHODS: To synthesize CuO NRs, 0.1M of CuSO4.5H2O solution was added to aqueous extract of Momordica charantia in a 1:3 (v/v) ratio (pH=11) and heated at 50°C followed by washing and drying. The synthesized CuO NRs were subjected to characterization using different analytical techniques such as UV visible spectroscopy, zeta sizer equipped with zeta potential, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) equipped with energy-dispersive X-ray spectroscopy (EDS) and transmission electron microscopy (TEM). Further, the application as a biomedical therapeutic potential was evaluated in vitro using well diffusion method against eleven multidrug-resistant clinical bacterial strains, a fungus- Trichophyton rubrum and in ovo against the R2B virus using haemagglutination (HA) test. RESULTS: Characterization was preliminarily done by the spectral study that confirms the absorbance band at 245nm. FTIR analysis at 628 cm-1 peak identified copper oxide vibration. SEM analysis revealed agglomerated particle clusters. However, with TEM clear nanorods of average diameter of 61.48 ± 2 nm were observed. EDAX confirmed CuO formation while XRD showed a typical monoclinic structure with 6 nm crystallite size. Biological screening of CuO NRs showed significant results against both in vitro and in ovo methods. Significant inhibitory activity (p<0.0001) was noted against most of the resistant human pathogenic strains including both Gram-positive and Gram-negative bacteria. The highest efficacy was observed against Bacillus cereus with a 31.66 mm zone of inhibition. Besides, the therapeutic potential of CuO NRs against Corynebacterium xerosis, Streptococcus viridians and R2B strain of Newcastle disease is reported for the first time. CONCLUSION: Based on the present results, it could be expected that green synthesized CuO NRs would find potential applications in the field of nanomedicine.


Asunto(s)
Antibacterianos/farmacología , Cobre/farmacología , Tecnología Química Verde , Momordica charantia/química , Nanoestructuras/química , Animales , Antifúngicos/farmacología , Bacterias/efectos de los fármacos , Pollos , Hongos/efectos de los fármacos , Pruebas de Hemaglutinación , Humanos , Nanopartículas del Metal/química , Nanopartículas del Metal/ultraestructura , Pruebas de Sensibilidad Microbiana , Nanoestructuras/ultraestructura , Nanotubos/química , Nanotubos/ultraestructura , Tamaño de la Partícula , Espectrometría por Rayos X , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Electricidad Estática , Difracción de Rayos X
6.
Curr Drug Targets ; 20(12): 1227-1243, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31486747

RESUMEN

Cancer is the second leading cause of morbidity and mortality worldwide. Although chemotherapy and radiotherapy enhance the survival rate of cancerous patients but they have several acute toxic effects. Therefore, there is a need to search for new anticancer agents having better efficacy and lesser side effects. In this regard, herbal treatment is found to be a safe method for treating and preventing cancer. Here, an attempt has been made to screen some less explored medicinal plants like Ammania baccifera, Asclepias curassavica, Azadarichta indica, Butea monosperma, Croton tiglium, Hedera nepalensis, Jatropha curcas, Momordica charantia, Moringa oleifera, Psidium guajava, etc. having potent anticancer activity with minimum cytotoxic value (IC50 >3µM) and lesser or negligible toxicity. They are rich in active phytochemicals with a wide range of drug targets. In this study, these medicinal plants were evaluated for dose-dependent cytotoxicological studies via in vitro MTT assay and in vivo tumor models along with some more plants which are reported to have IC50 value in the range of 0.019-0.528 mg/ml. The findings indicate that these plants inhibit tumor growth by their antiproliferative, pro-apoptotic, anti-metastatic and anti-angiogenic molecular targets. They are widely used because of their easy availability, affordable price and having no or sometimes minimal side effects. This review provides a baseline for the discovery of anticancer drugs from medicinal plants having minimum cytotoxic value with minimal side effects and establishment of their analogues for the welfare of mankind.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Neoplasias/tratamiento farmacológico , Plantas Medicinales/química , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/uso terapéutico , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Humanos , Concentración 50 Inhibidora , Neoplasias/metabolismo , Extractos Vegetales/química , Extractos Vegetales/farmacología
7.
Mediterr J Hematol Infect Dis ; 9(1): e2017034, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28512563

RESUMEN

Acquired von Willebrand syndrome (AVWS) is a rare hemorrhagic disorder that occurs in patients with no prior personal or family history of bleeding. Here, we describe a case of AVWS occurring after autologous stem cell transplantation (ASCT). Interestingly, AVWS developed after bortezomib-based induction and conditioning regimens. Recent evidence suggests that the proximity of the bortezomib therapy to the collection of stem cells with consequent depletion of regulatory T cells after the conditioning regimen could explain some of the unusual autoimmune complications reported in patients receiving bortezomib prior to ASCT. In addition, this patient developed a secondary MGUS post-ASCT, which may have also contributed to the AVWS. To the best of our knowledge, this is the first case of post-ASCT AVWS reported. Prospective data is needed to better elucidate the mechanisms by which these unusual complications occur in patients receiving bortezomib prior to ASCT.

8.
Clin Gastroenterol Hepatol ; 14(10): 1473-1480.e3, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27189915

RESUMEN

BACKGROUND & AIMS: The severe depletion of muscle mass at the third lumbar vertebral level (sarcopenia) is a marker of malnutrition and is independently associated with mortality in patients with cirrhosis. Instead of monitoring sarcopenia by cross-sectional imaging, we investigated whether ultrasound-based measurements of peripheral muscle mass, measures of muscle function, along with nutritional factors, are associated with severe loss of muscle mass. METHODS: We performed a prospective study of 159 outpatients with cirrhosis (56% male; mean age, 58 ± 10 years; mean model for end-stage liver disease score, 10 ± 3; 60% Child-Pugh class A) evaluated at the Cirrhosis Care Clinic at the University of Alberta Hospital from March 2011 through September 2012. Lumbar skeletal muscle indices were determined by computed tomography or magnetic resonance imaging. We collected clinical data and data on patients' body composition, nutrition, and thigh muscle thickness (using ultrasound analysis). We also measured mid-arm muscle circumference, mid-arm circumference, hand grip, body mass index, and serum level of albumin; patients were evaluated using the subjective global assessment scale. Findings from these analyses were compared with those from cross-sectional imaging, for each sex, using logistic regression analysis. RESULTS: Based on cross-sectional imaging analysis, 43% of patients had sarcopenia (57% of men and 25% of women). Results from the subjective global assessment, serum level of albumin, and most nutritional factors were significantly associated with sarcopenia. We used multivariate analysis to develop a model to identify patients with sarcopenia, and developed a nomogram based on body mass index and thigh muscle thickness for patients of each sex. Our model identified men with sarcopenia with an area under the receiver operating characteristic curve value of 0.78 and women with sarcopenia with an area under the receiver operating characteristic curve value of 0.89. CONCLUSIONS: In a prospective study of patients with cirrhosis, we found that the combination of body mass index and thigh muscle thickness (measured by ultrasound) can identify male and female patients with sarcopenia almost as well as cross-sectional imaging (area under the receiver operating characteristic curve values of 0.78 and 0.89, respectively). These factors might be used in screening and routine nutritional monitoring of patients with cirrhosis.


Asunto(s)
Técnicas de Apoyo para la Decisión , Fibrosis/complicaciones , Sarcopenia/diagnóstico por imagen , Sarcopenia/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Alberta , Índice de Masa Corporal , Femenino , Hospitales Universitarios , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Fuerza Muscular , Pacientes Ambulatorios , Estudios Prospectivos , Curva ROC , Suero/química , Tomografía Computarizada por Rayos X , Ultrasonografía , Adulto Joven
9.
Can J Gastroenterol Hepatol ; 28(2): 83-8, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24288693

RESUMEN

BACKGROUND: Spontaneous bacterial peritonitis (SBP) is the most prevalent bacterial infection in patients with cirrhosis. Although studies from Europe have reported significant rates of resistance to third-generation cephalosporins, there are limited SBP-specific data from centres in North America. OBJECTIVE: To evaluate the prevalence of, predictors for and clinical impact of third-generation cephalosporin-resistant SBP at a Canadian tertiary care centre, and to summarize the data in the context of the existing literature. METHODS: SBP patients treated with both antibiotics and albumin therapy at a Canadian tertiary care hospital between 2003 and 2011 were retrospectively identified. Multivariate logistic regression was used to determine independent predictors of third-generation cephalosporin resistance and mortality. RESULTS: In 192 patients, 25% of infections were nosocomial. Forty per cent (77 of 192) of infections were culture positive; of these, 19% (15 of 77) were resistant to third-generation cephalosporins. The prevalence of cephalosporin resistance was 8% with community-acquired infections, 17% with health care-associated infections and 41% with nosocomial acquisition. Nosocomial acquisition of infection was the only predictor of resistance to third-generation cephalosporins (OR 4.0 [95% CI 1.04 to 15.2]). Thirty-day mortality censored for liver transplantation was 27% (50 of 184). In the 77 culture-positive patients, resistance to third-generation cephalosporins (OR 5.3 [1.3 to 22]) and the Model for End-stage Live Disease score (OR 1.14 [1.04 to 1.24]) were independent predictors of 30-day mortality. CONCLUSIONS: Third-generation cephalosporin-resistant SBP is a common diagnosis and has an effect on clinical outcomes. In an attempt to reduce the mortality associated with resistance to empirical therapy, high-risk subgroups should receive broader empirical antibiotic coverage.


Asunto(s)
Antibacterianos/farmacología , Infecciones Bacterianas/tratamiento farmacológico , Cefalosporinas/farmacología , Peritonitis/tratamiento farmacológico , Infecciones Bacterianas/etiología , Infecciones Bacterianas/mortalidad , Canadá/epidemiología , Resistencia a las Cefalosporinas , Estudios de Cohortes , Infecciones Comunitarias Adquiridas/tratamiento farmacológico , Infecciones Comunitarias Adquiridas/epidemiología , Infecciones Comunitarias Adquiridas/etiología , Infección Hospitalaria/tratamiento farmacológico , Infección Hospitalaria/epidemiología , Infección Hospitalaria/etiología , Femenino , Humanos , Cirrosis Hepática/complicaciones , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Peritonitis/etiología , Peritonitis/mortalidad , Prevalencia , Estudios Retrospectivos
10.
Am J Gastroenterol ; 108(9): 1473-9, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23877350

RESUMEN

OBJECTIVES: Clinicians do not have a validated tool for estimating the short-term mortality associated with spontaneous bacterial peritonitis (SBP). Accurate prognosis assessment is important for risk stratification and for individualizing therapy. We aimed therefore to develop and validate a model for the prediction of 30-day mortality in SBP patients receiving standard medical treatment (antibiotics and if indicated by guidelines, intravenous albumin therapy). METHODS: We retrospectively identified SBP patients treated at a tertiary care center between 2003 and 2011 (training set). Multivariate regression modeling and receiver operating characteristic (ROC) curves were utilized for statistical analysis. An external data set of 109 SBP patients was utilized for validation. RESULTS: Of the 184 patients in the training set, 66% were men with a median age of 55 years, a median MELD (Model for End-Stage Liver Disease) score of 20, and a 30-day mortality of 27%. Peripheral blood leukocyte count ≥11×109 cells/l (odds ratio (OR) 2.5; 95% confidence interval CI: 1.2-5.2) and MELD score ≥22 (OR 4.6; 95% CI: 2.3-9.6) were independent predictors of 30-day mortality. Patients with neither, one, or both variables had 30-day mortality rates of 8%, 32%, and 52%, respectively. The findings in the validation set mirrored the training set. CONCLUSIONS: In cirrhotic patients with SBP receiving standard therapy, MELD score ≥22 and peripheral blood leukocyte count ≥11×109 cells/l are validated independent predictors of mortality. The mortality in a patient without either poor prognostic variable is ≤10% and with both variables is ≥50%. Trials aiming to reduce mortality should target patients in the moderate-risk to high-risk groups.


Asunto(s)
Infecciones Bacterianas/mortalidad , Cirrosis Hepática/mortalidad , Modelos Teóricos , Peritonitis/mortalidad , Anciano , Antibacterianos/uso terapéutico , Infecciones Bacterianas/complicaciones , Infecciones Bacterianas/tratamiento farmacológico , Femenino , Humanos , Cirrosis Hepática/complicaciones , Cirrosis Hepática/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Peritonitis/complicaciones , Peritonitis/tratamiento farmacológico , Peritonitis/microbiología , Pronóstico , Estudios Retrospectivos , Riesgo , Medición de Riesgo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...