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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 246: 119034, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33049470

RESUMO

In this study, surface enhanced Raman spectroscopy (SERS) and Raman spectroscopy (RS), are employed for the classification of different stages of breast cancer using clinically diagnosed serum samples from breast cancer patients and healthy individuals. These serum samples are compared for their spectral features acquired by SERS and RS to establish spectral features that can be considered as spectral markers of breast cancer diagnosis and classification. SERS features related to DNA, proteins and lipids were observed which are solely observed in the serum samples of patients at different stages of breast cancer as compared to healthy samples. In order to explore the capability of SERS and RS and their comparison as an analytical tool for the efficient understanding of the progression of breast cancer, Principal Component Analysis (PCA) is done for the SERS and RS spectra of control, stage 2, stage 3 and stage 4. Furthermore, the Partial Least Squares-Discriminant Analysis (PLS-DA) was performed to compare the diagnostic performance of SERS and Raman spectroscopy for the classification of disease positive samples and healthy ones. The sensitivity and specificity and area under receiver operating characteristic (AUROC) curve values for SERS data were 90%, 98.4%, and 94% respectively which were higher as compared to Raman spectral data for which these values were found to be 88.2%, 97.7%, and 83.4% respectively.


Assuntos
Neoplasias da Mama , Análise Espectral Raman , Neoplasias da Mama/diagnóstico , Análise Discriminante , Humanos , Análise de Componente Principal , Sensibilidade e Especificidade
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 222: 117210, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31176149

RESUMO

Raman spectroscopy was employed for the characterization of blood plasma samples from patients at different stages of breast cancer. Blood plasma samples taken from clinically diagnosed breast cancer patients were compared with healthy controls using multivariate data analysis techniques (principal components analysis - PCA) to establish Raman spectral features which can be considered spectral markers of breast cancer development. All the stages of the disease can be differentiated from normal samples. It is also found that stage 2 and 3 are biochemically similar, but can be differentiated from each other by PCA. The Raman spectral data of the stage 4 is found to be biochemically distinct, but very variable between patients. Raman spectral features associated with DNA and proteins were identified, which are exclusive to patient plasma samples. Moreover, there are several other spectral features which are strikingly different in the blood plasma samples of different stages of breast cancer. In order to further explore the potential of Raman spectroscopy as the basis of a minimally invasive screening technique for breast cancer diagnosis and staging, PCA-Factorial Discriminant Analysis (FDA) was employed to classify the Raman spectral datasets of the blood plasma samples of the breast cancer patients, according to different stages of the disease, yielding promisingly high values of sensitivity and specificity for all stages.


Assuntos
Neoplasias da Mama/sangue , Análise Espectral Raman , Biomarcadores Tumorais/sangue , Mama/patologia , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Análise Discriminante , Feminino , Humanos , Análise de Componente Principal , Análise Espectral Raman/métodos
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 200: 136-142, 2018 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-29677500

RESUMO

Infection with the dengue virus is currently clinically detected according to different biomarkers in human blood plasma, commonly measured by enzyme linked immunosorbent assays, including non-structural proteins (Ns1), immunoglobulin M (IgM) and immunoglobulin G (IgG). However, there is little or no mutual correlation between the biomarkers, as demonstrated in this study by a comparison of their levels in samples from 17 patients. As an alternative, the label free, rapid screening technique, Raman spectroscopy has been used for the characterisation/diagnosis of healthy and dengue infected human blood plasma samples. In dengue positive samples, changes in specific Raman spectral bands associated with lipidic and amino acid/protein content are observed and assigned based on literature and these features can be considered as markers associated with dengue development. Based on the spectroscopic analysis of the current, albeit limited, cohort of samples, Principal Components Analysis (PCA) coupled Factorial Discriminant Analysis, yielded values of 97.95% sensitivity and 95.40% specificity for identification of dengue infection. Furthermore, in a comparison of the normal samples to the patient samples which scored low for only one of the biomarker tests, but high or medium for either or both of the other two, PCA-FDA demonstrated a sensitivity of 97.38% and specificity of 86.18%, thus providing an unambiguous screening technology.


Assuntos
Dengue/diagnóstico , Programas de Rastreamento , Análise Espectral Raman/métodos , Biomarcadores/sangue , Dengue/sangue , Análise Discriminante , Humanos , Imunoglobulina G/sangue , Análise de Componente Principal
4.
J Biol Regul Homeost Agents ; 32(1): 101-106, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29504372

RESUMO

Herbs and plants are mostly used as antimicrobials and antioxidants owing to the harmfulness and linked side-effects of synthetic chemical constituents. Plants and spices produce various metabolites with antibacterial and antioxidant potential. These metabolites are principally revealed as encouraging healing components or mediators which control ailments in human beings. The present study was aimed to characterize the extracts from selected medicinal plants through in-vitro activities. Winged prickly ash, green tea and thyme were selected and extracted through ethanol and methanol solutions. The extracts were assessed for antibacterial and antioxidant activities. The antibacterial potential of extracts showed the significant extent of the activity against Bacillus subtilis and E. coli. The maximum activity was noted in 80% methanolic fraction of Thymus vulgaris (15.20±0.64 mm) against Bacillus subtilis. Antioxidant potential exhibited the highest phenolic and flavonoid content in Camellia sinensis . The total phenolic content was significantly higher (1456.26±12.05 mg gallic acid) in 80% ethanolic fraction of Camellia sinensis. The flavonoid content in different plant extracts ranged from 8.17±2.02 to 376.29±7.11 mg/g. The radical scavenging DPPH assay also showed the significant antioxidant capacity of selected plants with the methanolic (50%) extract of Camellia sinensis found to be the most potent (78.95±7.12%). It was concluded that the alcoholic extracts of selected medicinal plants revealed the effective antibacterial and antioxidant activity, showing protective prospective against oxidative injury.


Assuntos
Antibacterianos , Antioxidantes , Bacillus subtilis/crescimento & desenvolvimento , Camellia sinensis/química , Escherichia coli/crescimento & desenvolvimento , Thymus (Planta)/química , Zanthoxylum/química , Antibacterianos/química , Antibacterianos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia
5.
Bioprocess Biosyst Eng ; 35(3): 433-40, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21947702

RESUMO

Present work describes the bioleaching potential of metals from low-grade mining ore containing smithsonite, sphaerocobaltite, azurite and talc as main gangue minerals with adapted consortium of Sulfobacillus thermosulfidooxidans strain-RDB and Thermoplasma acidophilum. Bioleaching potential improved markedly by added energy source, acid preleaching and adaptation of microbial consortium with mixed metal ions. During whole leaching period including acid preleaching stage of 960 h and bioleaching stage of 212 days about 76% Co, 70% Zn, 84% Cu, 72% Ni and 63% Fe leached out.


Assuntos
Bacilos Gram-Positivos Formadores de Endosporo/crescimento & desenvolvimento , Metais/química , Mineração , Talco/química , Thermoplasma/crescimento & desenvolvimento , Bacilos Gram-Positivos Formadores de Endosporo/metabolismo , Metais/metabolismo , Thermoplasma/metabolismo
6.
Biodegradation ; 18(3): 311-6, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17004031

RESUMO

Four different aerobic mixed consortia collected from basins of wastewater streams coming out of dying plants of Crescent Textile (CT), Sitara Textile (ST), Chenab Fabrics (CF) and Noor Fatima Textile (NF), Faisalabad, Pakistan were applied for decolorization of Drimarene Orange K-GL, Drimarene Brilliant Red K-4BL, Foron Yellow SE4G and Foron Blue RDGLN for 10 days using the shake flask technique. CT culture showed the best decolorization potential on all dyestuffs followed by ST, NF and CF, respectively. CT could completely decolorize all dyes within 3-5 days. ST cultures showed effective decolorization potential on Foron Yellow SE4G and Drimarene Brilliant Red K-4BL but complete color removal was achieved after 4 and 7 days, respectively. NF culture showed 100% decolorization efficiencies on Foron Yellow SE4G and Foron Blue RDGLN but it took comparatively longer time periods (5-7 days). Where as, the NF culture had decolorized only 40% and 50% of Drimarene orange and red, respectively, after 10 days. CF caused complete decolorization of Foron Blue RDGLN and Drimarene Brilliant Red K-4BL after 4 and 8 days, respectively but it showed poor performance on other two dyes.


Assuntos
Bactérias/metabolismo , Corantes/metabolismo , Resíduos Industriais , Têxteis , Biodegradação Ambiental , Cor
7.
Protein Pept Lett ; 13(8): 799-804, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17073725

RESUMO

A novel peroxidase isolated from a local chick pea (Cicer arietinum L.) cultivar (Balksar 2000) was purified by means of ammonium sulfate precipitation, DEAE-cellulose chromatography and two runs on gel filtration. The purified enzyme has a specific activity of 2045 U/mg with 17 % activity recovery. The molecular mass of the enzyme was estimated to be 39 kDa by SDS-polyacrylamide gel electrophoresis. Optimum pH and temperature of the enzyme were 5.5 and 45 degrees C respectively. The thermal denaturation of local chick pea peroxidase was studied in aqueous solution at temperatures ranging from 45 degrees C to 65 degrees C. The temperature of 50% inactivation of the enzyme was found to be 68 degrees C. The enthalpy (DeltaH*) and free energy (DeltaG*) of thermal denaturation of chick pea peroxidase were 101.4 and 103.4 k J/mol respectively at 65 degrees C. Metals like Zn2+, Mn2+, Hg2+, Co2+ and Al3+ slightly inhibited the peroxidase activity while Ca2+, Mg2+ and Ba2+ have no effect on enzyme activity. The high specific activity and thermal stability make chick pea peroxidase an alternative to horseradish peroxidase (HRP) in various applications.


Assuntos
Cicer/enzimologia , Peroxidase/química , Peroxidase/isolamento & purificação , Sulfato de Amônio/química , Cromatografia DEAE-Celulose/métodos , Ativação Enzimática/efeitos dos fármacos , Estabilidade Enzimática/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Metais/farmacologia , Peroxidase/metabolismo , Temperatura , Termodinâmica
8.
Can J Microbiol ; 52(6): 519-24, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16788719

RESUMO

An intracellular glucose oxidase (GOD) was isolated from the mycelium extract of a locally isolated strain of Aspergillus niger NFCCP. The enzyme was partially purified to a yield of 28.43% and specific activity of 135 U mg(-1) through ammonium sulfate precipitation, anion-exchange chromatography, and gel filtration. The enzyme showed high specificity for D-glucose, with a K(m) value of 25 mmol L(-1). The enzyme exhibited optimum catalytic activity at pH 5.5. Optimum temperature for GOD-catalyzed D-glucose oxidation was 40 degrees C. The enzyme displayed a high thermostability having a half-life (t(1/2)) of 30 min, enthalpy of denaturation (H*) of 99.66 kJ mol(-1), and free energy of denaturation (G*) of 103.63 kJ mol(-1). These characteristics suggest that GOD from A. niger NFCCP can be used as an analytical reagent and in the design of biosensors for clinical, biochemical, and diagnostic assays.


Assuntos
Aspergillus niger/enzimologia , Glucose Oxidase/isolamento & purificação , Termodinâmica , Aspergillus niger/isolamento & purificação , Aspergillus niger/metabolismo , Estabilidade Enzimática , Glucose Oxidase/química , Glucose Oxidase/metabolismo , Concentração de Íons de Hidrogênio , Cinética , Temperatura
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