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1.
Drug Dev Ind Pharm ; : 1-9, 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38980706

RESUMEN

OBJECTIVE: To develop a Raman spectroscopy-based analytical model for quantification of solid dosage forms of active pharmaceutical ingredient (API) of Atenolol.Significance: For the quantitative analysis of pharmaceutical drugs, Raman Spectroscopy is a reliable and fast detection method. As part of this study, Raman Spectroscopy is explored for the quantitative analysis of different concentrations of Atenolol. METHODS: Various solid-dosage forms of Atenolol were prepared by mixing API with excipients to form different solid-dosage formulations of Atenolol. Multivariate data analysis techniques, such as Principal Component Analysis (PCA) and Partial least square regression (PLSR) were used for the qualitative and quantitative analysis, respectively. RESULTS: As the concentration of the drug increased in formulation, the peak intensities of the distinctive Raman spectral characteristics associated with the API (Atenolol) gradually increased. Raman spectral data sets were classified using PCA due to their distinctive spectral characteristics. Additionally, a prediction model was built using PLSR analysis to assess the quantitative relationship between various API (Atenolol) concentrations and spectral features. With a goodness of fit value of 0.99, the root mean square errors of calibration (RMSEC) and prediction (RMSEP) were determined to be 1.0036 and 2.83 mg, respectively. The API content in the blind/unknown Atenolol formulation was determined as well using the PLSR model. CONCLUSIONS: Based on these results, Raman spectroscopy may be used to quickly and accurately analyze pharmaceutical samples and for their quantitative determination.

2.
ACS Omega ; 9(28): 30071-30086, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39035943

RESUMEN

This review will unveil the development of a new generation of electrochemical sensors utilizing a transition-metal-oxide-based nanocomposite with varying morphology. There has been considerable discussion on the role of transition metal oxide-based nanocomposite, including iron, nickel, copper, cobalt, zinc, platinum, manganese, conducting polymers, and their composites, in electrochemical and biosensing applications. Utilizing these materials to detect glucose and hydrogen peroxide selectively and sensitively with the correct chemical functionalization is possible. These transition metals and their oxide nanoparticles offer a potential method for electrode modification in sensors. Nanotechnology has made it feasible to develop nanostructured materials for glucose and H2O2 biosensor applications. Highly sensitive and selective biosensors with a low detection limit can detect biomolecules at nanomolar to picomolar (10-9 to 10-12 molar) concentrations to assess physiological and metabolic parameters. By mixing carbon-based materials (graphene oxide) with inorganic nanoparticles, nanocomposite biosensor devices with increased sensitivity can be made using semiconducting nanoparticles, quantum dots, organic polymers, and biomolecules.

3.
Nat Prod Res ; : 1-8, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38946520

RESUMEN

Antimicrobial resistance is a major health burden in Pakistan, and therefore new herbal medicine-based therapeutic regimens are being largely investigated. Limbarda crithmoides essential oil was extracted by using hydrodistillation method. Chemical profiling of essential was evaluated by using FTIR and GC-MS analysis. A total of 20 components were identified including, p-xylene, o-xylene, ß-linalool, acetophenole and 3-isopropylphenyl methylcarbamate. The HOMO and LUMO analysis in DFT investigations presented that 3-isopropylphenyl methylcarbamate, p-xylene and o-xylene posess a substantial capacity to transfer charge through molecules. The antimicrobial potential of essential oil showed moderate inhibition against E. coli (MIC = 6.25 mg/mL), whereras a significant inhibition Staphylococos aureus was recorded (MIC = 3.12 mg/mL). Further, significant antioxidant activities were recorded in DPPH radical scavenging (IC50 = 80.5 µg/mL), H2O2 (64 ± 1.2%) and FRAP (60.3 µg ferrous equivalents) assays. It was therefore concluded that Limbarda crithmoides essential oil has potential antioxidant and anti-antimicrobial properties and can be used for further investigations.

4.
RSC Adv ; 14(28): 20290-20299, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38932985

RESUMEN

Fossil fuels are considered vital natural energy resources on the Earth, and sulfur is a natural component present in them. The combustion of fossil fuels releases a large amount of sulfur in the form of SO x in the atmosphere. SO x is the major cause of environmental problems, mainly air pollution. The demand for fuels with ultra-low sulfur is growing rapidly. In this aspect, microorganisms are proven extremely effective in removing sulfur through a process known as biodesulfurization. A major part of sulfur in fossil fuels (coal and oil) is present in thiophenic structures such as dibenzothiophene (DBT) and substituted DBTs. In this study, the identification and characterization of DBT desulfurizing bacteria (Chryseobacterium sp. IS, Gordonia sp. 4N, Mycolicibacterium sp. J2, and Rhodococcus sp. J16) based on their specific biochemical constituents were conducted using surface-enhanced Raman spectroscopy (SERS). By differentiating DBT desulfurizing bacteria, researchers can gain insights into their unique characteristics, thus leading to improved biodesulfurization strategies. SERS was used to differentiate all these species based on their biochemical differences and different SERS vibrational bands, thus emerging as a potential technique. Moreover, multivariate data analysis techniques such as principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were employed to differentiate these DBT desulfurizing bacteria on the basis of their characteristic SERS spectral signals. For all these isolates, the accuracy, sensitivity, and specificity are above 90%, and an AUC (area under the curve) value of close to 1 was achieved for all PLS-DA models.

5.
Spectrochim Acta A Mol Biomol Spectrosc ; 320: 124534, 2024 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-38878718

RESUMEN

In this study, Gordonia sp. HS126-4N was employed for dibenzothiophene (DBT) biodesulfurization, tracked over 9 days using SERS. During the initial lag phase, no significant spectral changes were observed, but after 48 h, elevated metabolic activity was evident. At 72 h, maximal bacterial population correlated with peak spectrum variance, followed by stable spectral patterns. Despite 2-hydroxybiphenyl (2-HBP) induced enzyme suppression, DBT biodesulfurization persisted. PCA and PLS-DA analysis of the SERS spectra revealed distinctive features linked to both bacteria and DBT, showcasing successful desulfurization and bacterial growth stimulation. PLS-DA achieved a specificity of 95.5 %, sensitivity of 94.3 %, and AUC of 74 %, indicating excellent classification of bacteria exposed to DBT. SERS effectively tracked DBT biodesulfurization and bacterial metabolic changes, offering insights into biodesulfurization mechanisms and bacterial development phases. This study highlights SERS' utility in biodesulfurization research, including its use in promising advancements in the field.


Asunto(s)
Bacteria Gordonia , Espectrometría Raman , Tiofenos , Tiofenos/metabolismo , Tiofenos/química , Espectrometría Raman/métodos , Bacteria Gordonia/metabolismo , Azufre/metabolismo , Azufre/química , Biodegradación Ambiental
6.
Mol Biol Rep ; 51(1): 771, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38900353

RESUMEN

OBJECTIVE: Channidae family, are major freshwater fish species amongst the local aquatic fauna of Pakistan, while, there is limited availability of local data on their molecular identification and phylogenetic analysis. METHODS: Channa species were collected from four different geographical sites in the tertiary of Punjab province on the Indus and Chenab rivers of Pakistan. Morphometric records and molecular techniques were used to determine the intraspecific variations among populations of Channa marulius. Mitochondrial DNA was extracted from the flesh of C. marulius, while, COI gene was used for molecular identification and variation levels were estimated by using Principal Component Analysis. RESULTS: Data recorded on the basis of morphometric parameters clearly divided the C. marulius of different locations into two distinct categories, which accounted for a cumulative variability of 97.6%. Non-significance (P < 0.05) among the C. marulius showed that it contains a unique control haplotype localized within the sub-population. The intra-species distance ranged from 0.000 to 0.001 for four different populations, in contrast, the sequences retrieved from the NCBI database exhibited a range span of 0.000-0.003, while, sequence diversity ranged from 0.000 to 0.006 for this intra-specific comparison. The cladogram was also constructed for C. marulius of different geographical locations for observation of phylogenetic relationship. The conclusion drawn from the phylogenetic analysis of C. marulius populations used in this study, contributes significantly to the understanding of genetic variations within populations of this species. The findings provide valuable insight to devise conservation strategies in fisheries management programs in Pakistan.


Asunto(s)
ADN Mitocondrial , Peces , Filogenia , Ríos , Pakistán , Animales , ADN Mitocondrial/genética , Peces/genética , Peces/clasificación , Variación Genética/genética , Haplotipos/genética , Complejo IV de Transporte de Electrones/genética
7.
Cureus ; 16(4): e57615, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38707031

RESUMEN

Ovarian granulosa cell tumors (GCTs) are rare neoplasms with a unique incidence pattern peaking in postmenopausal women. This case report presents two instances of stage 4 recurrent adult GCTs with a prolonged 20-year follow-up. Patient 1, diagnosed at 54 years, experienced multiple recurrences managed through surgery, hormonal therapy, and chemotherapy, culminating in hepatocellular carcinoma. Patient 2, diagnosed at 67 years, underwent various treatments, including surgery, chemotherapy, and hormonal therapy, demonstrating disease stability. Despite the generally favorable prognosis, these cases highlight the challenges of managing recurrent GCTs, emphasizing the need for tailored therapeutic approaches.

8.
RSC Adv ; 14(25): 17389-17396, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38813128

RESUMEN

Bacterial resistance towards antibiotics is a significant challenge for public health, and surface-enhanced Raman spectroscopy (SERS) has great potential to be a promising technique to provide detailed information about the effect of antibiotics against biofilms. SERS is employed to check the antibacterial potential of a lab synthesized drug ([bis(1,3-dipentyl-1H-imidazol-2(3H)-ylidene)silver(i)] bromide) against Bacillus subtilis and to analyze various SERS spectral features of unexposed and exposed Bacillus strains by observing biochemical changes in DNA, protein, lipid and carbohydrate contents induced by the lab synthesized imidazole derivative. Further, PCA and PLS-DA are employed to differentiate the SERS features. PCA was employed to differentiate the biochemical contents of unexposed and exposed Bacillus strains in the form of clusters of their representative SERS spectra and is also helpful in the pairwise comparison of two spectral data sets. PLS-DA provides authentic information to discriminate different unexposed and exposed Bacillus strains with 91% specificity, 93% sensitivity and 97% accuracy. SERS can be employed to characterize the complex and heterogeneous system of biofilms and to check the changes in spectral features of Bacillus strains by exposure to the lab synthesized imidazole derivative.

9.
Chem Asian J ; 19(14): e202400245, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38634677

RESUMEN

A highly flexible, tunable morphology membrane with excellent thermal stability and ionic conductivity can endow lithium metal batteries with high power density and reduced dendrite growth. Herein, a porous Polyurethane (PU) membrane with an adjustable morphology was prepared by a simple nonsolvent-induced phase separation technique. The precise control of the final morphology of PU membranes can be achieved through appropriate selection of a nonsolvent, resulting a range of pore structures that vary from finger-like voids to sponge-like pores. The implementation of combinatorial DFT and experimental analysis has revealed that spongy PU porous membranes, especially PU-EtOH, show superior electrolyte wettability (472%), high porosity (75%), good mechanical flexibility, robust thermal dimensional stability (above 170 °C), and elevated ionic conductivity (1.38 mS cm-1) in comparison to the polypropylene (PP) separator. The use of PU-EtOH in Li//Li symmetric cell results in a prolonged lifespan of 800 h, surpasing the longevity of PU or PP cells. Moreover, when subjected to a high rate of 5 C, the LiFePO4/Li half-cell with a PU-EtOH porous membrane displayed better cycling performance (115.4 mAh g-1) compared to the PP separator (104.4 mAh g-1). Finally, the prepared PU porous membrane exhibits significant potential for improving the efficiency and safety of LMBs.

10.
Front Vet Sci ; 11: 1351693, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38681848

RESUMEN

Introduction: The utilization of fauna and fauna-based byproducts in ethnomedicinal usages has been a longstanding human activity, practiced across various cultures worldwide. This study focuses on investigating the utilization of animal-based traditional medicine by the people of Pakistan, specifically in the Gujranwala area. Methods: Data collection took place from January to September 2019 through interviews with local communities. Ethnomedicinal applications of animal products were analyzed using several indices, including Relative Frequency of Citation (RFC), Relative Popularity Level (RPL), Folk Use Value (FL), and Relative Occurrence Percentage (ROP). Results: The study identified the use of different body parts of 54 species of animals in treating various diseases and health issues. These include but are not limited to skin infections, sexual problems, pain management (e.g., in the backbone and joints), eyesight issues, immunity enhancement, cold, weakness, burns, smallpox, wounds, poisoning, muscular pain, arthritis, diabetes, fever, epilepsy, allergies, asthma, herpes, ear pain, paralysis, cough, swelling, cancer, bronchitis, girls' maturity, and stomach-related problems. Certain species of fauna were noted by informers with high "frequency of citation" (FC), ranging from 1 to 77. For instance, the black cobra was the most frequently cited animal for eyesight issues (FC = 77), followed by the domestic rabbit for burn treatment (FC = 67), and the Indus Valley spiny-tailed ground lizard for sexual problems (FC = 66). Passer domesticus and Gallus gallus were noted to have the highest ROP value of 99. Discussion: The findings of this study provide valuable preliminary insights for the conservation of fauna in the Gujranwala region of Punjab, Pakistan. Additionally, screening these animals for medicinally active compounds could potentially lead to the development of novel animal-based medications, contributing to both traditional medicine preservation and modern pharmaceutical advancements.

11.
Environ Sci Pollut Res Int ; 31(21): 30886-30901, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38619768

RESUMEN

This study attempts to identify factors that significantly encourage the cessation of smoking in the context of Pakistan. The study distributes a modified questionnaire among 421 respondents (current as well as former smokers) in the capital city of Pakistan, Islamabad. The binary regression method was employed to data for analyzing predictors of making quit attempts and successful smoking cessation. The result indicates that respondents having strong intentions to quit, high socioeconomic status, low nicotine dependency, and past quit attempts, and those having no-smoking friends, are more likely to quit cigarette smoking successfully. On the other hand, factors like social pressure to quit smoking, religious information against smoking, intention to quit smoking, and public regulation on smoking are more likely to encourage smokers to make quit attempts. The study calls for community and school-wide smoking cessation campaigns involving officials, peers and parents, religious leaders, and other influential individuals to inform people about the dangers of smoking. In addition, religious leaders should be encouraged to issue rulings against smoking especially during "Friday Prayer." Furthermore, the government should pronounce more strict and comprehensive regulations on smoking by properly monitoring its implementation to encourage cessation of cigarette smoking.


Asunto(s)
Cese del Hábito de Fumar , Fumar , Pakistán , Humanos , Fumar/epidemiología , Masculino , Encuestas y Cuestionarios , Femenino , Adulto
12.
Heliyon ; 10(7): e28926, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38576549

RESUMEN

The water quality in Karachi (Pakistan) is uncertain due to the occurrence of fungi and other microorganisms. A total of twenty-five water samples were collected from public places, educational institutes, hospitals, water supply systems and surface water of the canal of Karachi (Pakistan). The different fungal species including Acremonium sp., Alternaria alternata, Aspergillus flavus, A. fumigatus, A. sulphureus, Cladosporium sp., Fusarium sp., Clonostachys (Gliocladium) sp., Macrophomina phaseolina, Mucor racemosus, Paecilomyces sp. Penicillium chrysogenum, P. citrinum, P. commune, P. expansum, Rhizoctonia sp. and Stachybotrys sp. were isolated from these drinking water samples. However, the bacteria, microalgae and some other microorganisms were present in low concentrations. The reason for fungi infection and production of mycotoxicity depends upon various factors and the availability of their nutrients in filtration plants. The major threats to human health are fungal mycotoxicity which is responsible for carcinogenic and other lethal diseases. Mostly, the genus Aspergillus was dominated and isolated with a maximum of 88-98% of occurrence in the different samples of drinking water by the direct plate-spread method. For the control of fungi, various Physico-chemical coagulation treatments were used, but Potassium alum, clay pot, and hot water treatment disinfected effectively 69-70% removal of the fungi and its spore or mycelia from the water. In addition, it is concluded that drinking water purifications such as chlorination, filtration and lime did not eliminate thermophilic fungal spores or mycelia including Penicillium, Paecilomyces and Mucor from the water.

13.
ACS Omega ; 9(13): 15202-15209, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38585125

RESUMEN

In this study, surface-enhanced Raman spectroscopy (SERS) technique, along with principal component analysis (PCA) and partial least-squares discriminant analysis (PLS-DA), is used as a simple, quick, and cost-effective analysis method for identifying biochemical changes occurring due to induced mutations in the Aspergillus niger fungus strain. The goal of this study is to identify the biochemical changes in the mutated fungal cells (cell mass) as compared to the control/nonmutated cells. Furthermore, multivariate data analysis tools, including PCA and PLS-DA, are used to further confirm the differentiating SERS spectral features among fungal samples. The mutations are caused in A. niger by the clustered regularly interspaced palindromic repeat CRISPR-Cas9 genomic editing method to improve their biotechnological potential for the production of cellulase enzyme. SERS was employed to detect the changes in the cells of mutated A. niger fungal strains, including one mutant producing low levels of an enzyme and another mutant producing high levels of the enzyme as a result of mutation as compared with an unmutated fungal strain as a control sample. The distinctive features of SERS corresponding to nucleic acids and proteins appear at 546, 622, 655, 738, 802, 835, 959, 1025, 1157, 1245, 1331, 1398, and 1469 cm-1. Furthermore, PLS-DA is used to confirm the 89% accuracy, 87.7% precision, 87% sensitivity, and 88.9% specificity of this method, and the value of the area under the curve (AUROC) is 0.67. It has been shown that surface-enhanced Raman spectroscopy is an effective method for identifying and differentiating biochemical changes in genome-modified fungal samples.

14.
Nanomaterials (Basel) ; 14(8)2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38668164

RESUMEN

In this paper, we explore the asymmetry observed between the effects of photon-phonon coupling (nested-dressing) and a crystal field (CF) on the fine structure of fluorescence (FL) and spontaneous four-wave mixing (SFWM) in Eu3+: BiPO4 and Eu3+: NaYF4. The competition between the CF and the strong photon-phonon dressing leads to dynamic splitting in two directions. The CF leads to static splitting in one direction under weak phonon dressing. The evolution from strong dressing to weak dressing results in spectral asymmetry. This spectral asymmetry includes out-of-phase FL and in-phase SFWM. Further, the large ratio between the dressing Rabi frequency and the de-phase rate leads to strong FL and SFWM asymmetry due to photon-phonon constructive dressing. Moreover, the experimental results suggest the analogy of a spectra asymmetry router with a channel equalization ratio of 96.6%.

15.
Adv Mater ; 36(26): e2401110, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38549546

RESUMEN

Manipulating the structural and kinetic dissociation processes of water at the catalyst-electrolyte interface is vital for alkaline hydrogen evolution reactions (HER) at industrial current density. This is seldom actualized due to the intricacies of the electrochemical reaction interface. Herein, this work introduces a rapid, nonequilibrium cooling technique for synthesizing ternary Turing catalysts with short-range ordered structures (denoted as FeNiRu/C). These advanced structures empower the FeNiRu/C to exhibit excellent HER performance in 1 m KOH with an ultralow overpotential of 6.5 and 166.2 mV at 10 and 1000 mA cm-2, respectively, and a specific activity 7.3 times higher than that of Pt/C. Comprehensive mechanistic analyses reveal that abundant atomic species form asymmetric atomic electric fields on the catalyst surface inducing a directed evolution and the dissociation process of interfacial H2O molecules. In addition, the locally topologized structure effectively mitigates the high hydrogen coverage of the active site induced by the high current density. The establishment of the relationship between free water population and HER activity provides a new paradigm for the design of industrially relevant high performance alkaline HER catalysts.

16.
Spectrochim Acta A Mol Biomol Spectrosc ; 313: 124126, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38490122

RESUMEN

Large amount of sulphur is released by the combustion of fossil fuels in the form of SoX which affects human health and leads to acid rain. To overcome this issue, it is essential to eliminate sulphur moieties from heterocyclic organo-sulphur compounds like Dibenzothiophene (DBT) present in the petrol. In this study Surface enhanced Raman scattering (SERS) spectroscopy is used to analyze the desulfurizing activity of Tsukamurella paurometabola bacterial strain. The most prominent SERS peaks observed at 791, 837, 944 and 1032 cm-1, associated to C-S stretching, are solely observed in dibenzothiophene and its metabolite-I (DBTS) but absent in 2-Hydroxybiphenyl (metabolite-II) and extraction sample of supernatant as a result of biodesulfurization. Moreover, the SERS peaks observed at 974 (characteristic peak of benzene ring) and 1015 cm-1 is associated to C-C ring breathing while 1642 and 1655 cm-1 assigned to CC bonds of aromatic ring. These peaks are only observed in 2-Hydroxybiphenyl (metabolite-II) and extraction sample of supernatant as a result of biodesulfurization. Notably, these peaks are absent in the Dibenzothiophene and its metabolite-I which indicate that aromatic ring is carrying sulfur in this fraction. Moreover, multivariate data analytical tools like principal component analysis (PCA) and PCA-loadings are applied to further differentiate between dibenzothiophene and its metabolites that are Dibenzothiophene sulphone (metabolite-I) and 2-Hydroxybiphenyl (metabolite-II).


Asunto(s)
Actinobacteria , Compuestos de Bifenilo , Espectrometría Raman , Azufre , Tiofenos , Humanos , Azufre/química , Biodegradación Ambiental
18.
RSC Adv ; 14(12): 8548-8555, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38482068

RESUMEN

The ability of surface-enhanced Raman spectroscopy (SERS) to generate spectroscopic fingerprints has made it an emerging tool for biomedical applications. The objective of this study is to confirm the potential use of Raman spectroscopy for early disease diagnosis based on blood serum. In this study, a total of sixty blood serum samples, consisting of forty from diseased patients and twenty (controls) from healthy individuals, was used. Because disease biomarkers, found in the lower molecular weight fraction, are suppressed by higher molecular weight proteins, 50 kDa Amicon ultrafiltration centrifugation devices were used to produce two fractions from whole blood serum consisting of a filtrate, which is a low molecular weight fraction, and a residue, which is a high molecular weight fraction. These fractions were then analyzed, and their SERS spectral data were compared with those of healthy fractions. The SERS technique was utilized on blood serum, filtrate and residue of patients with tuberculosis to identify characteristic SERS spectral features associated with the development of disease, which can be used to differentiate them from healthy samples using silver nanoparticles as a SERS substrate. For further analysis, the effective chemometric technique of principal component analysis (PCA) was used to qualitatively differentiate all the analyzed samples based on their SERS spectral features. Partial least squares discriminant analysis (PLS-DA) accurately classified the filtrate portions of healthy and tuberculosis samples with 97% accuracy, 97% specificity, 98% sensitivity, and an area under the receiver operating characteristic (AUROC) curve of 0.74.

19.
RSC Adv ; 14(8): 5425-5434, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38348301

RESUMEN

Drug-resistant pathogenic bacteria are a major cause of infectious diseases in the world and they have become a major threat through the reduced efficacy of developed antibiotics. This issue can be addressed by using bacteriophages, which can kill lethal bacteria and prevent them from causing infections. Surface-enhanced Raman spectroscopy (SERS) is a promising technique for studying the degradation of infectious bacteria by the interaction of bacteriophages to break the vicious cycle of drug-resistant bacteria and help to develop chemotherapy-independent remedial strategies. The phage (viruses)-sensitive Staphylococcus aureus (S. aureus) bacteria are exposed to bacteriophages (Siphoviridae family) in the time frame from 0 min (control) to 50 minutes with intervals of 5 minutes and characterized by SERS using silver nanoparticles as SERS substrate. This allows us to explore the effects of the bacteriophages against lethal bacteria (S. aureus) at different time intervals. The differentiating SERS bands are observed at 575 (C-C skeletal mode), 620 (phenylalanine), 649 (tyrosine, guanine (ring breathing)), 657 (guanine (COO deformation)), 728-735 (adenine, glycosidic ring mode), 796 (tyrosine (C-N stretching)), 957 (C-N stretching (amide lipopolysaccharides)), 1096 (PO2 (nucleic acid)), 1113 (phenylalanine), 1249 (CH2 of amide III, N-H bending and C-O stretching (amide III)), 1273 (CH2, N-H, C-N, amide III), 1331 (C-N stretching mode of adenine), 1373 (in nucleic acids (ring breathing modes of the DNA/RNA bases)) and 1454 cm-1 (CH2 deformation of saturated lipids), indicating the degradation of bacteria and replication of bacteriophages. Multivariate data analysis was performed by employing principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA) to study the biochemical differences in the S. aureus bacteria infected by the bacteriophage. The SERS spectral data sets were successfully differentiated by PLS-DA with 94.47% sensitivity, 98.61% specificity, 94.44% precision, 98.88% accuracy and 81.06% area under the curve (AUC), which shows that at 50 min interval S. aureus bacteria is degraded by the replicating bacteriophages.

20.
Spectrochim Acta A Mol Biomol Spectrosc ; 310: 123968, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38330510

RESUMEN

Methicillin-resistant Staphylococcus aureus (MRSA) is gram positive bacteria and leading cause of a wide variety of diseases. It is a common cause of hospitalized and community-acquired infections. Development of increasing antibiotic-resistance by methicillin-resistant S. aureus (MRSA) strains demand to develop alternate novel therapies. Bacteriophages are now widely used as antibacterial therapies against antibiotic-resistant gram-positive pathogens. So, there is an urgent need to find fast detection techniques to point out phage susceptible and resistant strains of methicillin-resistant S. aureus (MRSA) bacteria. Samples of two separate strains of bacteria, S. aureus, in form of pellets and supernatant, were used for this purpose. Strain-I was resistant to phage, while the other (strain-II) was sensitive. Surface Enhanced Raman Spectroscopy (SERS) has detected significant biochemical changes in these bacterial strains of pellets and supernatants in the form of SERS spectral features. The protein portion of these two types of strains of methicillin-resistant S. aureus (MRSA) in their relevant pellets and supernatants is major distinguishing biomolecule as shown by their representative SERS spectral features. In addition, multivariate data analysis techniques such as principal component analysis (PCA) and a partial least squares-discriminant analysis (PLS-DA) were found to be helpful in identifying and characterizing various strains of S. aureus which are sensitive and resistant to bacteriophage with 100% specificity, 100% accuracy, and 99.8% sensitivity in case of SERS spectral data sets of bacterial cell pellets. Moreover, in case of supernatant samples, the results of PLS-DA model including 95.5% specificity, 96% sensitivity, and 96.5% accuracy are obtained.


Asunto(s)
Bacteriófagos , Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Humanos , Staphylococcus aureus , Espectrometría Raman , Antibacterianos/farmacología , Infecciones Estafilocócicas/microbiología , Pruebas de Sensibilidad Microbiana
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