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1.
J Assoc Physicians India ; 72(1): 43-46, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38736073

RESUMEN

INTRODUCTION: A survey-based approach to managing antibiotic-resistant infections in the intensive care unit (ICU) setting, with a focus on carbapenem-resistant Enterobacteriaceae (CRE) cases, was conducted. Among CRE, New Delhi metallo-ß-lactamase 1 (NDM-1) is a carbapenemase that is resistant to ß-lactam antibiotics and has a broader spectrum of antimicrobial resistance than other carbapenemase types. The article explains that healthcare-associated infections (HAIs) are a significant problem, particularly in low- and middle-income countries, and that carbapenem in combination with other antibiotics are the most potent class of antimicrobial agents effective in treating life-threatening bacterial infections, including those caused by resistant strains. AIM: The survey aimed to gather critical care healthcare professionals (HCPs') opinions on their current practices in managing infections acquired in the hospital and ICU settings, with a focus on CRE cases, specifically NDM-1 and other antibiotic-resistant infections. METHODS: Responses from critical care healthcare professionals, including online surveys and in-person interviews, to gain insights into the management of infections caused by multidrug-resistant bacteria. The findings related to the insights on the prevalence of bacterial flora, clinical experiences on efficacy and safety of meropenem sulbactam ethylenediaminetetraacetic acid (EDTA) (MSE) in CRE cases, and various combination therapies of antibiotics used to treat antibiotic-resistant infections in ICU setting were evaluated. RESULTS: Klebsiella pneumoniae bacteria were the most common bacteria in cultures, followed by Escherichia coli, Pseudomonas aeruginosa, and Acinetobacter baumannii. NDM-1 was the type of carbapenemase found in around 50% of CRE patients. MSE is among the most preferred antibiotics besides colistin, polymyxin B, and ceftazidime avibactum for CRE cases and specifically for NDM-1 cases due to its high rate of efficacy and safety. CONCLUSION: The article concludes with a discussion on the antibiotics used in response to CRE cases, reporting that critical care HCP considers MSE with high efficacy and safe antibiotic combination and was used as both monotherapy and in combination with other antibiotics. The survey highlights the need for exploring and better understanding the role of MSE in the management of CRE infections, especially in NDM-1.


Asunto(s)
Antibacterianos , Enterobacteriaceae Resistentes a los Carbapenémicos , Cuidados Críticos , Infecciones por Enterobacteriaceae , Unidades de Cuidados Intensivos , Humanos , Antibacterianos/uso terapéutico , Infecciones por Enterobacteriaceae/tratamiento farmacológico , Cuidados Críticos/métodos , Infección Hospitalaria/tratamiento farmacológico , Infección Hospitalaria/microbiología , Encuestas y Cuestionarios , beta-Lactamasas , Farmacorresistencia Bacteriana Múltiple , Meropenem/uso terapéutico , India , Actitud del Personal de Salud , Polimixina B/uso terapéutico , Carbapenémicos/uso terapéutico , Carbapenémicos/farmacología , Klebsiella pneumoniae/efectos de los fármacos , Personal de Salud
2.
Sci Rep ; 14(1): 9206, 2024 04 22.
Artículo en Inglés | MEDLINE | ID: mdl-38649731

RESUMEN

Periodic quantification of blood glucose levels is performed using painful, invasive methods. The proposed work presents the development of a noninvasive glucose-monitoring device with two sensors, i.e., finger and wrist bands. The sensor system was designed with a near-infrared (NIR) wavelength of 940 nm emitter and a 900-1700 nm detector. This study included 101 diabetic and non-diabetic volunteers. The obtained dataset was subjected to pre-processing, exploratory data analysis (EDA), data visualization, and integration methods. Ambiguities such as the effects of skin color, ambient light, and finger pressure on the sensor were overcome in the proposed 'niGLUC-2.0v'. niGLUC-2.0v was validated with performance metrics where accuracy of 99.02%, mean absolute error (MAE) of 0.15, mean square error (MSE) of 0.22 for finger, and accuracy of 99.96%, MAE of 0.06, MSE of 0.006 for wrist prototype with ridge regression (RR) were achieved. Bland-Altman analysis was performed, where 98% of the data points were within ± 1.96 standard deviation (SD), 100% were under zone A of the Clarke Error Grid (CEG), and statistical analysis showed p < 0.05 on evaluated accuracy. Thus, niGLUC-2.0v is suitable in the medical and personal care fields for continuous real-time blood glucose monitoring.


Asunto(s)
Automonitorización de la Glucosa Sanguínea , Glucemia , Humanos , Glucemia/análisis , Automonitorización de la Glucosa Sanguínea/instrumentación , Automonitorización de la Glucosa Sanguínea/métodos , Masculino , Femenino , Adulto , Dedos , Persona de Mediana Edad , Muñeca , Técnicas Biosensibles/instrumentación , Técnicas Biosensibles/métodos , Diabetes Mellitus/sangre , Diabetes Mellitus/diagnóstico
3.
Cureus ; 15(7): e42073, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37602104

RESUMEN

INTRODUCTION: Geriatric hip fractures are the new global pandemic. It is predicted to reach 7.3-21.3 million cases worldwide by 2050. Even with optimal care, geriatric patients suffer a higher morbidity and mortality rate when compared with the general population and often demand expensive hospital aftercare. This study aims to assess the implications of the successful adoption of the enhanced recovery after surgery (ERAS) protocol in the management of geriatric hip fractures in an Indian facility. METHODS: This is a retrospective study conducted in a tertiary care hospital in India and reported following REporting of studies Conducted using the Observational Routinely collected health Data (RECORD) guidelines. We included all geriatric patients over 60 years of age who were admitted with hip fractures for surgical management between January 2021 and January 2023. The individual perioperative components of the ERAS protocol focus on key areas such as preoperative nutritional support, effective multimodal analgesia with optimal pain control, fluid management, and early postoperative mobilization. RESULTS: Thirty-eight geriatric patients with a mean age of 77.5 (± 9.6) years were included for analysis. Twenty-three patients sustained intertrochanteric fractures and underwent fixation with proximal femur nailing and the remaining had 15 sustained neck or femur fractures of which 11 underwent hemiarthroplasty surgery and the remaining four underwent a total hip replacement. The mean time to surgery was 2 (± 0.2) days. Eighty-two percent (n=31) of the patients were mobilized with a walking frame within a day after surgery and were followed up after discharge with home physiotherapy. The mean time to ambulation was 2 (± 0.62) days. The mean length of stay was 4 (± 1.6) days. We had a 30-day readmission rate of 5.2% (n=2) and a 30-day mortality rate of 5.2% (n=2). The one-year mortality rate was 13% (n=5). CONCLUSION: Management of geriatric hip fractures requires exceptional interdisciplinary coordination and carefully planned strategies to optimize patient care. With the implementation of the ERAS protocol, we could perceive clinical benefits in terms of early recovery and short length of hospital stay in patients with hip fractures. Further comparative studies are required, which can determine the relative importance of individual measures in the ERAS protocol and understand their longer-term outcomes in hip fracture surgeries.

4.
Vet Parasitol Reg Stud Reports ; 31: 100728, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35569913

RESUMEN

Trypanosoma evansi, a unicellular haemoflagellate, causes surra in bovines and other economically important livestock species. We report here the epidemiological variables associated with the high prevalence of T. evansi infection in cattle in the plain agro-climatic zone of Chhattisgarh state, India. A total of 920 blood and sera samples were tested by a combination of parasitological, molecular and serodiagnostic tests. An overall prevalence of T. evansi was recorded as 4.57% (95% CI: 3.22-5.92%), 6.09% (95% CI: 4.54-7.63%), 63.91% (95% CI: 60.81-67.01%) and 55.33% (95% CI: 52.12-58.54%) by direct microscopy, PCR, ELISA and IFAT, respectively. The Chi-Square test established a significant correlation between the prevalence of T. evansi and the season, breed and place of the study, while the association with the gender and age of the animals was insignificant. The analysis of the prevalence ratio revealed a significant association of the breed, season and place of study with the prevalence of T. evansi. As per PR observed, the prevalence was 1.63 times higher in summer and 1.68 times higher in the rainy season than in the winter (reference season). The prevalence was higher in all the districts as compared to Rajnandgaon (reference district). The prevalence ratio in Sahiwal and HF cross-breed cattle was significantly higher than the Gir breed of cattle (reference). Durg district recorded the highest prevalence of surra, and the difference was significant. The medium IFAT titre, determined in a large number of sera collected from Durg, predicted a higher incidence of trypanosomosis in that district. Since T. evansi has a broad host range, the study predicted that a large population of livestock in Chhattisgarh state were at high risk of T. evansi infection. Treatment of the subclinically and clinically infected animals with selective curative drugs, such as diminazene aceturate, isometamidium chloride or the combination of quinapyramine sulphate and quinapyramine chloride, could help restore productivity and help in containing the infection.


Asunto(s)
Enfermedades de los Bovinos , Trypanosoma , Tripanosomiasis , Animales , Bovinos , Enfermedades de los Bovinos/epidemiología , Diminazeno , Ganado , Prevalencia , Tripanosomiasis/epidemiología , Tripanosomiasis/veterinaria
5.
Elife ; 92020 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-33048047

RESUMEN

Imaging neuronal activity with high and homogeneous spatial resolution across the field-of-view (FOV) and limited invasiveness in deep brain regions is fundamental for the progress of neuroscience, yet is a major technical challenge. We achieved this goal by correcting optical aberrations in gradient index lens-based ultrathin (≤500 µm) microendoscopes using aspheric microlenses generated through 3D-microprinting. Corrected microendoscopes had extended FOV (eFOV) with homogeneous spatial resolution for two-photon fluorescence imaging and required no modification of the optical set-up. Synthetic calcium imaging data showed that, compared to uncorrected endoscopes, eFOV-microendoscopes led to improved signal-to-noise ratio and more precise evaluation of correlated neuronal activity. We experimentally validated these predictions in awake head-fixed mice. Moreover, using eFOV-microendoscopes we demonstrated cell-specific encoding of behavioral state-dependent information in distributed functional subnetworks in a primary somatosensory thalamic nucleus. eFOV-microendoscopes are, therefore, small-cross-section ready-to-use tools for deep two-photon functional imaging with unprecedentedly high and homogeneous spatial resolution.


Asunto(s)
Microscopía de Fluorescencia por Excitación Multifotónica/métodos , Tálamo/diagnóstico por imagen , Animales , Conducta Animal , Endoscopios , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL , Microscopía de Fluorescencia por Excitación Multifotónica/instrumentación , Neuronas/fisiología , Tálamo/fisiología
7.
J Biophotonics ; 12(9): e201900028, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31081280

RESUMEN

Stimulated Raman scattering (SRS) microscopy is a label-free method generating images based on chemical contrast within samples, and has already shown its great potential for high-sensitivity and fast imaging of biological specimens. The capability of SRS to collect molecular vibrational signatures in bio-samples, coupled with the availability of powerful statistical analysis methods, allows quantitative chemical imaging of live cells with sub-cellular resolution. This application has substantially driven the development of new SRS microscopy platforms. Indeed, in recent years, there has been a constant effort on devising configurations able to rapidly collect Raman spectra from samples over a wide vibrational spectral range, as needed for quantitative analysis by using chemometric methods. In this paper, an SRS microscope which exploits spectral shaping by a narrowband and rapidly tunable acousto-optical tunable filter (AOTF) is presented. This microscope enables spectral scanning from the Raman fingerprint region to the Carbon-Hydrogen (CH)-stretch region without any modification of the optical setup. Moreover, it features also a high enough spectral resolution to allow resolving Raman peaks in the crowded fingerprint region. Finally, application of the developed SRS microscope to broadband hyperspectral imaging of biological samples over a large spectral range from 800 to 3600 cm-1 , is demonstrated.


Asunto(s)
Microscopía Óptica no Lineal/métodos , Espectrometría Raman/métodos , Carbono/química , Línea Celular Tumoral , Células Hep G2 , Humanos , Hidrógeno/química , Oscilometría , Polimetil Metacrilato/química , Poliestirenos/química , Vibración
8.
Horm Metab Res ; 51(4): 248-255, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31022740

RESUMEN

The objective of the study is the functional characterization of a novel POU1F1 c.605delC mutation in combined pituitary hormone deficiency (CPHD) and to report the clinical and genetic details of 160 growth hormone deficiency patients. Screening of GH1, GHRHR, POU1F1, PROP1, and HESX1 genes by Sanger sequencing was carried out in 160 trios and 100 controls followed by characterization of the POU1F1 c.605delC mutation by expression studies including site directed mutagenesis, co-transfection, protein degradation, and luciferase assays to compare the wild type and mutant POU1F1. In vitro studies showed that the POU1F1 c.605delC mutation codes for a truncated protein with reduced transactivation capacity on its downstream effectors, viz., growth hormone (GH) and prolactin (PRL) causing severe CPHD. Experiments using different protease inhibitors reveal rescue of the protein upon blockage of the lysosomal pathway that might be useful in novel drug designing using targeted approach thereby maintaining the milieu and preventing/delaying the disease. The study provides an insight into the disease causing mechanism of POU1F1 c.605delC mutation identified in a CPHD child with severe short stature and failure to thrive. It also shows mutation effect on the expression, function and turnover of protein and highlights mechanistic details by which these potent regulators may operate.


Asunto(s)
Enanismo Hipofisario/genética , Pruebas Genéticas , Mutación/genética , Factor de Transcripción Pit-1/genética , Niño , Femenino , Hormona de Crecimiento Humana/genética , Humanos , Hipopituitarismo/genética , Masculino , Proteínas Mutantes/metabolismo , Tasa de Mutación , Prolactina/genética , Dominios Proteicos , Proteolisis , Factor de Transcripción Pit-1/química , Activación Transcripcional/genética
9.
Spectrochim Acta A Mol Biomol Spectrosc ; 206: 622-629, 2019 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-30056036

RESUMEN

The fluorescence quenching of Acriflavine (AFN) by certain estrogens was examined in aqueous media by employing steady state and time-resolved fluorescence measurements. The absorption spectra of AFN change with significant bathochromic shift in presence of quencher molecules. The quenching behavior was examined by correlating the bimolecular quenching rate constant (kq) with the free energy change (ΔG). The decrease in quenching rate constant depends on the increase in oxidation potential of quencher molecules. The fluorescence quenching experiments were carried out in different solvents of varying polarities and reveals the possibility of charge transfer quenching mechanism. Lifetime measurements indicate static quenching. The quenching behavior is addressed from bond dissociation enthalpy (BDE) calculations. The antioxidant activity of estrogen compounds were evaluated by deoxyribose oxidation assay.


Asunto(s)
Acriflavina/química , Antioxidantes/química , Estrógenos/química , Colorantes Fluorescentes/química , Acriflavina/metabolismo , Antioxidantes/metabolismo , Estrógenos/metabolismo , Colorantes Fluorescentes/metabolismo , Oxidación-Reducción , Espectrometría de Fluorescencia , Termodinámica
10.
Pediatr Obes ; 13(2): 94-102, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-27923101

RESUMEN

BACKGROUND AND OBJECTIVES: Most studies describing childhood obesity in the United States are based on cross-sectional surveys and do not include substantial numbers of American Indians (AI). Secular trends in height and weight reflect general health status. This study describes weight trends and transitions among AI children over a 43-year period. METHODS: Anthropometric data were obtained from a prospective study conducted in a southwestern US AI population (1965 through 2007). For cross-sectional analysis, 12 377 observations were available from 6529 children across four birth cohorts (1955-1964, 1965-1974, 1975-1984, 1985-1994). Participants were stratified into three age groups: pre- (5-9 years), early (10-13) and late (14-17) adolescence. Longitudinal analyses included 1737 children with one exam in each age group. RESULTS: In early and late adolescence, weight increased across birth cohorts. Prevalence of obesity among pre-adolescents was 17.5% (95% CI, 15.1%-19.9%) in the 1955-1964 cohort and 33.7% (95% CI, 30.1%-36.4%) in the 1985-1994 cohort. 74% of children overweight in pre-adolescence in the 1985-1994 cohort became obese by late adolescence; in the 1955-1964 cohort, only 43% made this transition. CONCLUSIONS: This study describes the rising prevalence of childhood obesity. Children obese in pre-adolescence remained obese in late adolescence, stressing the need for early intervention.


Asunto(s)
Antropometría , Índice de Masa Corporal , Indígenas Norteamericanos/estadística & datos numéricos , Obesidad Infantil/epidemiología , Adolescente , Factores de Edad , Peso Corporal , Niño , Desarrollo Infantil , Preescolar , Femenino , Humanos , Estudios Longitudinales , Masculino , Prevalencia , Estudios Prospectivos , Sudoeste de Estados Unidos/epidemiología
11.
Acta Virol ; 61(1): 66-76, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28161961

RESUMEN

The differences in the influenza viral pathogenesis observed between different pathogenic strains are associated with distinct properties of virus strains and the host immune responses. In order to determine the differences in the duck immune response against two different pathogenic strains, we studied genome-wide host immune gene response of ducks infected with A/duck/India/02CA10/2011 and A/duck/Tripura/103597/2008 H5N1 viruses using custom-designed microarray. A/duck/India/02CA10/2011 is highly pathogenic virus (HP) to ducks, whereas A/duck/Tripura/103597/2008 is a low pathogenic (LP) virus strain. Comparative lung tissue transcriptome analysis of differentially expressed genes revealed that 686 genes were commonly expressed, 880 and 1556 genes are expressed uniquely to infection with HP and LP virus, respectively. The up-regulation of chemokines (CCL4 and CXCR4) and IFN-stimulated genes (IFITM2, STAT3, TGFB1 and TGFB3) was observed in the lung tissues of ducks infected with HP virus. The up-regulation of other immune genes (IL17, OAS, SOCS3, MHC I and MHC II) was observed in both infection conditions. The expression of important antiviral immune genes MX, IFIT5, IFITM5, ISG12, ß-defensins, RSAD2, EIF2AK2, TRIM23 and SLC16A3 was observed in LP virus infection, but not in HP virus infection. Several immune-related gene ontology terms and pathways activated by both the viruses were qualitatively similar but quantitatively different. Based on these findings, the differences in the host immune response might explain a part of the difference observed in the viral pathogenesis of high and low pathogenic influenza strains in ducks.


Asunto(s)
Patos , Regulación de la Expresión Génica/inmunología , Estudio de Asociación del Genoma Completo , Subtipo H5N1 del Virus de la Influenza A/patogenicidad , Gripe Aviar/virología , Animales , Análisis por Matrices de Proteínas , Virulencia
12.
Stem Cells ; 33(1): 35-44, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25186497

RESUMEN

The cancer stem cell (CSC) model is describing tumors as a hierarchical organized system and CSCs are suggested to be responsible for cancer recurrence after therapy. The identification of specific markers of CSCs is therefore of paramount importance. Here, we show that high levels of lipid droplets (LDs) are a distinctive mark of CSCs in colorectal (CR) cancer. This increased lipid content was clearly revealed by label-free Raman spectroscopy and it directly correlates with well-accepted CR-CSC markers as CD133 and Wnt pathway activity. By xenotransplantation experiments, we have finally demonstrated that CR-CSCs overexpressing LDs retain most tumorigenic potential. A relevant conceptual advance in this work is the demonstration that a cellular organelle, the LD, is a signature of CSCs, in addition to molecular markers. A further functional characterization of LDs could lead soon to design new target therapies against CR-CSCs.


Asunto(s)
Neoplasias Colorrectales/patología , Células Madre Neoplásicas/patología , Espectrometría Raman/métodos , Animales , Biomarcadores de Tumor/metabolismo , Neoplasias Colorrectales/metabolismo , Humanos , Gotas Lipídicas , Ratones , Células Madre Neoplásicas/metabolismo , Vía de Señalización Wnt
13.
J Back Musculoskelet Rehabil ; 26(3): 227-42, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23893137

RESUMEN

Recent evidences suggest functional thoracic hyperkyphosis (FTH) could be a different approach in the management of subacromial impingement syndrome (SIS). This case study aims firstly with the development of evidence informed FTH model for SIS. Secondly this study aimed to develop well defined multimodal physical therapy intervention for FTH and its related mechanical consequences in elderly patient with chronic SIS. As a result, Level IV positive evidence was found in both the short and long-term pain and disability of chronic SIS, using FTH model with 26 months of follow-up.


Asunto(s)
Cifosis/terapia , Síndrome de Abducción Dolorosa del Hombro/terapia , Terapia Cognitivo-Conductual , Femenino , Humanos , Cifosis/complicaciones , Cifosis/diagnóstico por imagen , Imagen por Resonancia Magnética , Persona de Mediana Edad , Dimensión del Dolor , Examen Físico , Modalidades de Fisioterapia , Radiografía , Síndrome de Abducción Dolorosa del Hombro/complicaciones , Síndrome de Abducción Dolorosa del Hombro/patología , Articulación del Hombro/patología , Vértebras Torácicas/diagnóstico por imagen
14.
J Back Musculoskelet Rehabil ; 25(4): 225-30, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23220803

RESUMEN

Osteitis pubis among soccer athletes is a disabling painful condition and it is difficult to manage without integrating a multimodal treatment approach. There is limited scientific evidence on the effectiveness of exercise in treating Osteitis pubis especially when it progress to a chronic painful condition. The purpose of this case report is to discuss the successful multimodal physiotherapeutic management for a 15-year old soccer athlete diagnosed with stage-IV Osteitis pubis. Land and water based active core muscle strengthening exercises, Proprioceptive neuromuscular facilitation techniques (PNF) and Manual Therapy are some of the essential components incorporated in multimodal intervention approach with emphasis to water based strength and endurance training exercises. The athlete was able to make progress to a successful recovery from his chronic painful condition and accomplished the clearly established clinical outcomes during each phase of rehabilitation.


Asunto(s)
Atletas , Osteítis/terapia , Modalidades de Fisioterapia , Hueso Púbico , Índice de Severidad de la Enfermedad , Fútbol , Adolescente , Terapia Combinada , Terapia por Ejercicio , Humanos , Masculino , Fuerza Muscular/fisiología , Manipulaciones Musculoesqueléticas , Osteítis/rehabilitación , Resultado del Tratamiento
15.
Phys Ther ; 92(4): 605-13, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22194280

RESUMEN

BACKGROUND AND PURPOSE: Disability in patients with facial paralysis is the result of impairment or loss of complex and multidimensional functions of the face, including expression of emotions, facial identity, and communication. However, the majority of interventions for facial paralysis are unidimensional and impairment oriented. Thus, a functional training program intended to address various dimensions of disability caused by facial paralysis was devised. This patient-centered, multidimensional approach to the rehabilitation of people with facial paralysis consists of patient education, functional training, and complementary exercises. This approach is focused on various dimensions of disability, including the physical, emotional, and social dimensions, by encouraging context-specific facial functions, positive coping strategies, and social interaction skills. CASE DESCRIPTION: The patient was a 25-year-old woman with chronic complete right facial paralysis caused by a postoperative complication of ear surgery. The patient's problems were evaluated with the Facial Disability Index (physical function subscale score=45/100, social/well-being function subscale score=28/100) and an informal interview exploring her experiences and priorities. OUTCOMES: After 8 weeks of functional training, the patient showed considerable improvement in facial functions (physical function subscale score=95/100, social/well-being function subscale score=100/100) and reported positive changes in social interactions and interpersonal relationships. DISCUSSION: The use of a functional training program was associated with positive changes in emotional expression, psychosocial function, and social integration, thus contributing to reduced disability of a person with chronic facial paralysis.


Asunto(s)
Parálisis Facial/rehabilitación , Modalidades de Fisioterapia , Adulto , Enfermedad Crónica , Evaluación de la Discapacidad , Femenino , Humanos , Recuperación de la Función
16.
J Nanosci Nanotechnol ; 10(2): 905-11, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20352735

RESUMEN

Intracellular biogenic nanoparticles are considered disadvantageous as the separation of the nanoparticles from the biomass becomes intricate. However realizing the importance of carbon supported catalyst for many important organic reactions we envisaged these nanoparticles as a source for carbon supported catalyst. Herein we demonstrate the heat treatment of intracellular biogenic nanoparticles under inert atmosphere as an efficient method for the preparation of carbon supported metal oxide catalysts. Aspergillus ochraceus, a fungus isolated from foundries, on incubation with K2TiF6 led to the synthesis of intracellular titanium oxide nanoparticles. The nanoparticles embedded biomass upon heat treatment at 600 degrees C in a nitrogen environment gave titanium oxide nanoparticles implanted in a carbonaceous matrix. The material thus formed was characterized using FTIR spectroscopy, Raman spectroscopy, HRTEM and X-ray diffraction. Appreciable benzaldehyde selectivity was observed when styrene oxidation was carried out over such immobilized catalysts. The conversion rate was determined to be 76% and the benzaldehyde selectivity was greater than 80%.


Asunto(s)
Carbono/química , Nanopartículas , Catálisis , Microscopía Electrónica de Transmisión , Oxidación-Reducción , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría Raman , Temperatura , Difracción de Rayos X
17.
Langmuir ; 26(8): 5772-81, 2010 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-20337478

RESUMEN

Polypeptide polymer-grafted silica nanoparticles are of considerable interest because the ordered secondary structure of the polypeptide grafts imparts novel functional properties onto the nanoparticle composite. The synthesis of poly-L-lysine-grafted silica nanoparticles would be of particular interest because the high density of cationic charges on the surface could lead to many applications such as gene delivery and antimicrobial agents. In this work, we have developed a "grafting-to" approach using a combination of NCA polymerization and "click chemistry" to synthesize poly-L-lysine-grafted silica nanoparticles with a high graft density of 1 chain/nm(2). The covalent attachment of poly-L-lysine to silica nanoparticles (PLL-silica) was confirmed using a variety of techniques such as (13)C CP MAS NMR, TGA, and IR. This methodology was then extended to graft poly-L-lysine-b-poly-L-leucine copolymer (PLL-b-PLLeu-silica) and poly-L-benzylglutamate (PLBG-silica) onto silica nanoparticles. All of these polypeptide-grafted nanoparticles show interesting aggregation properties in solution. The efficacy of PLL-silica and PLL-b-PLLeu-silica as antimicrobial agents was tested on both gram-negative E. coli and gram-positive Bacillus subtilis.


Asunto(s)
Nanopartículas/química , Polilisina/química , Polímeros/química , Polímeros/síntesis química , Dióxido de Silicio/química , Modelos Teóricos
18.
Langmuir ; 25(19): 11741-7, 2009 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-19746940

RESUMEN

Intracellular silver nanoparticles produced by exposing silver ions to the fungus Aspergillus ochraceus were heat-treated in nitrogen environment to yield silver nanoparticles embedded in carbonaceous supports. This carbonaceous matrix embedded silver nanoparticles showed antimicrobial properties against both bacteria (Gram-positive and Gram-negative) and virus (M 13 phage virus). The bactericidal effects were noticed even after washing and repeated exposure of these carbon supported silver nanoparticles to fresh bacterial cultures, revealing their sustained activity.


Asunto(s)
Carbono/química , Espacio Intracelular/metabolismo , Nanopartículas del Metal/química , Plata/química , Plata/metabolismo , Antibacterianos/biosíntesis , Antibacterianos/química , Antibacterianos/farmacología , Antivirales/química , Antivirales/metabolismo , Antivirales/farmacología , Aspergillus ochraceus/citología , Aspergillus ochraceus/metabolismo , Bacillus subtilis/efectos de los fármacos , Bacteriófago M13/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Plata/farmacología , Difracción de Rayos X
19.
J Matern Fetal Neonatal Med ; 11(5): 290-301, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-12389669

RESUMEN

The fetus and the neonate are particularly vulnerable to injury caused directly by immunologic mechanisms or inflicted by infectious agents that take advantage of their relatively immature and inexperienced immune system. With increasing survival of high-risk neonates in the surfactant era, prevention/treatment of sepsis and chronic lung disease (CLD) has emerged as an area of priority in neonatal research. Considering the role of inflammatory mediators in the pathogenesis of sepsis and CLD, the clinical application of immunomodulator therapy to neonatology is perhaps more important at present than ever. Advances in molecular biology and immunology have led to development of newer immune modulator therapies that are directed towards specific cells or cytokines rather than resulting in a general suppression of the immune response. Failure of promising, newer immunomodulator therapies in sepsis trials in adults has, however, clearly documented the difficulties in diagnosing/correcting the imbalance between pro- and anti-inflammatory responses. As in the case of sepsis, development of a single magic bullet for prevention/management of a multi-factorial illness like CLD may be difficult, as prevention of prematurity - the single most important high-risk factor for CLD - is an unachievable goal at present. As new frontiers are being explored, older, well-established therapies like antenatal anti-D immunoglobulin prophylaxis continue to emphasize the tremendous potential of immunomodulator therapy in neonatology/perinatology. The current immunomodulators/immunotherapeutic agents with established/potential clinical applications in the perinatal period are reviewed.


Asunto(s)
Adyuvantes Inmunológicos/fisiología , Adyuvantes Inmunológicos/uso terapéutico , Enfermedades del Recién Nacido/tratamiento farmacológico , Enfermedades del Recién Nacido/inmunología , Enfermedades Pulmonares/tratamiento farmacológico , Enfermedades Pulmonares/inmunología , Sepsis/tratamiento farmacológico , Sepsis/inmunología , Enfermedad Crónica , Cromolin Sódico/inmunología , Cromolin Sódico/uso terapéutico , Femenino , Glucocorticoides/inmunología , Glucocorticoides/uso terapéutico , Factores de Crecimiento de Célula Hematopoyética/inmunología , Factores de Crecimiento de Célula Hematopoyética/uso terapéutico , Humanos , Inmunoglobulinas/inmunología , Inmunoglobulinas/uso terapéutico , Inmunoglobulinas Intravenosas/inmunología , Inmunoglobulinas Intravenosas/uso terapéutico , Recién Nacido , Azul de Metileno/uso terapéutico , Leche Humana/inmunología , Neutrófilos/inmunología , Neutrófilos/trasplante , Pentoxifilina/inmunología , Pentoxifilina/uso terapéutico , Embarazo , Globulina Inmune rho(D)/inmunología , Globulina Inmune rho(D)/uso terapéutico
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