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1.
Biol Proced Online ; 24(1): 2, 2022 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-35067222

RESUMO

Highly infectious illnesses caused by pathogens constitute severe threats to public health and lead to global economic loss. The use of robust and programmable clustered regularly interspaced short palindromic repeat and CRISPR-associated protein (CRISPR-Cas) systems, repurposed from genome-engineering applications has markedly improved traditional nucleic acid detection for precise identification, independently enabling rapid diagnostics of multiplex biomarker with genetic and mutation related to tumors, and microbial pathogens. In this review, we delineate the utility of the current CRISPR-Cas enzyme as biosensors by which these effector toolkits achieve recognition, signaling amplification, and finally, accurate detection. Additionally, we discuss the details of the dominance and hurdles related to expanding this revolutionary technology into an effective and convenient contraption crucial for improving the rational redesign to CRISPR/Cas biosensing. Overall, this review provides an insight into the current status of rapid and POC diagnostic systems by CRISPR/Cas tools.

2.
Curr Microbiol ; 79(4): 118, 2022 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-35220467

RESUMO

The rapid emergence of resistance to third-generation cephalosporins in Shigella flexneri is crucial in pediatric shigellosis management. Limited studies have been conducted on molecular pattern of antibiotic resistance of S. flexneri in diarrhea endemic areas of Pakistan. The aim of the study was to analyze the antimicrobial resistance of S. flexneri isolated from pediatric diarrheal patients in Peshawar, Pakistan. A total of 199 S. flexneri isolates (clinical, n = 1 55 and non-clinical, n = 44) were investigated for drug resistance and mutational analysis of selected drug resistance genes. All isolates were found to be highly resistant to amoxicillin/clavulanic acid (88%), followed by trimethoprim-sulfamethoxazole (77%), chloramphenicol (43%), and quinolones (41.6%). About 34.5% S. flexneri isolates were found to be resistant to third-generation cephalosporin. None of the isolates was resistant to imipenem, piperacillin-tazobactam, and amikacin. Interestingly high frequency of third-generation cephalosporin resistance was observed in S. flexneri isolated from non-clinical samples (49%) when compared to clinical samples (30.5%). Furthermore, the most prevalent phenotypic-resistant patterns among third-generation cephalosporin-resistant isolates were AMC,CAZ,CPD,CFM,CRO,SXT (13%) followed by OFX,AMC,CAZ,CPD,CFM,CRO,SXT,NA,CIP (10%). The most frequently detected resistance genes were trimethoprim-sulfamethoxazole (sul2 = 84%), beta-lactamase genes (blaOXA = 87%), quinolones (qnrS = 77%), and chloramphenicol (cat = 64%). No mutation was detected in any drug-resistant genes. We are reporting for the first time the sequence of the blaTEM gene in S. flexneri. Furthermore, high third-generation cephalosporin resistance was observed in the patients who practiced self-medication as compared to those who took medication according to physician prescription. This study shows the high emergence of third-generation cephalosporin-resistant S. flexneri isolates, which is a potential threat to the community in the country. This finding will be helpful to develop a suitable antibiotic prescription regime to treat shigellosis.


Assuntos
Disenteria Bacilar , Shigella , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Resistência às Cefalosporinas/genética , Criança , Farmacorresistência Bacteriana/genética , Disenteria Bacilar/tratamento farmacológico , Disenteria Bacilar/epidemiologia , Humanos , Testes de Sensibilidade Microbiana , Paquistão/epidemiologia , Shigella flexneri
3.
Parasitol Res ; 121(9): 2481-2493, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35838795

RESUMO

Tick infestation is a major public and animal health concern causing significant financial losses, especially in tropical and subtropical regions of the world. This study aimed at investigating the epidemiologic profile of ticks infesting cattle and molecular identification of R. microplus in the centrally ignored part of Khyber Pakhtunkhwa, Pakistan. A total of 600 cattle from 20 farms were examined for the tick infestation, among them 358 (59.7%) cattle were infested with ticks. A total of 2118 nymph, larvae and adult tick stages were collected and morphologically identified followed by molecular confirmation of Rhipicephalus microplus. Host-based demographic and ecological parameter analysis revealed significantly higher tick infestation in adult, female, exotic, freely grazing, and with irregular/no acaricides treated cattle. The univariate logistic analysis showed that host age, gender, breed, acaricides use, and feeding method were significantly (P < 0.05) associated, whereas multivariate analysis revealed only host breed and feeding method were potential risk factors (P < 0.05) for tick infestation. Microscopy-based examination identified four different species of ticks including R. microplus (44.5%), Hyalomma anatolicum (38.5%), and Hyalomma marginatum (10.5%) and Hyalomma excavatum (6.5%). Tick infestation pattern showed that 55.9% of cattle was found co-infested with R. microplus and H. anatolicum followed by R. microplus and H. anatolicum and H. marginatum (29.3%) then R. microplus, H. anatolicum, H. marginatum, and H. excavatum (11.2%). Sequencing of the second internal transcribed spacer (ITS2-) and 16S rRNA gene fragments also confirmed the molecular identification of Rhipicephalus microplus. Phylogenetic analysis of ITS-2 revealed all sequences clustered in single clade of the R. microplus while the 16S rRNA nucleotide sequences showed that R. microplus in this study was clustered together in clade A along with other isolates from Pakistan, China, and India. The high tick infestation suggests the need for designing strategic and integrated control measures for ticks in order to ensure good health of domestic animals in this region of Pakistan.


Assuntos
Acaricidas , Doenças dos Bovinos , Ixodidae , Rhipicephalus , Infestações por Carrapato , Acaricidas/farmacologia , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Feminino , Paquistão/epidemiologia , Filogenia , RNA Ribossômico 16S/genética , Rhipicephalus/genética , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/veterinária
4.
Biomacromolecules ; 22(7): 3049-3059, 2021 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-34128646

RESUMO

Antibiotics' abuse in bacteria-infected wounds has threatened patients' lives and burdened medical systems. Hence, antibiotic-free hydrogel-based biomaterials, which exhibit biostability, on-demand release of antibacterial agents, and long-lasting antimicrobial activity, are highly desired for the treatment of chronic bacteria-infected wounds. Herein, we developed a hyaluronic acid (HA)-based composite hydrogel, with an antimicrobial peptide [AMP, KK(SLKL)3KK] as a cross-linking agent through Schiff's base formation, which exhibited an acidity-triggered release of AMP (pathological environment in bacteria-infected wounds, pH ∼ 5.5-5.6). During the self-assembly process, AMP adopted an antiparallel ß-sheet secondary structure due to the alternate arrangement of hydrophobic and hydrophilic residues of amino acids. Owing to Schiff's base formation between the primary amines derived from lysine residues and the aldehydes in oxidized HA, the AMP-HA composite hydrogel exhibited injectability, high biostability, and enhanced mechanical strength. Importantly, both AMP and the AMP-HA composite showed excellent broad-spectrum antibacterial activity in vitro and in vivo. Specifically, the AMP-HA composite hydrogel exhibited on-demand full thickness wound healing in an infected mice model. Therefore, this work provides an efficient strategy to fabricate antibiotic-free hydrogel-based biomaterials for the management of chronic bacteria-infected wounds.


Assuntos
Ácido Hialurônico , Hidrogéis , Animais , Antibacterianos/farmacologia , Concentração de Íons de Hidrogênio , Camundongos , Proteínas Citotóxicas Formadoras de Poros , Cicatrização
5.
Malar J ; 19(1): 206, 2020 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-32513171

RESUMO

BACKGROUND: The spread of artemisinin resistance in the Greater Mekong Subregion of Southeast Asia poses a significant threat for current anti-malarial treatment guidelines globally. The aim of this study was to assess the current prevalence of molecular markers of drug resistance in Plasmodium falciparum in the four provinces with the highest malaria burden in Pakistan, after introducing artemether-lumefantrine as first-line treatment in 2017. METHODS: Samples were collected during routine malaria surveillance in Punjab, Sindh, Baluchistan, and Khyber Pakhtunkhwa provinces of Pakistan between January 2018 and February 2019. Plasmodium falciparum infections were confirmed by rapid diagnostic test or microscopy. Plasmodium falciparum positive isolates (n = 179) were screened by Sanger sequencing for single nucleotide polymorphisms (SNPs) in the P. falciparum kelch 13 (pfk13) propeller domain and in P. falciparum coronin (pfcoronin). SNPs in P. falciparum multidrug resistance 1 (pfmdr1) N86Y, Y184F, D1246Y and P. falciparum chloroquine resistance transporter (pfcrt) K76T were genotyped by PCR-restriction fragment length polymorphism. RESULTS: No artemisinin resistance associated SNPs were identified in the pfk13 propeller domain or in pfcoronin. The pfmdr1 N86, 184F, D1246 and pfcrt K76 alleles associated with reduced lumefantrine sensitivity were present in 83.8% (150/179), 16.9% (29/172), 100.0% (173/173), and 8.4% (15/179) of all infections, respectively. The chloroquine resistance associated pfcrt 76T allele was present in 98.3% (176/179) of infections. CONCLUSION: This study provides an update on the current prevalence of molecular markers associated with reduced P. falciparum sensitivity to artemether and/or lumefantrine in Pakistan, including a first baseline assessment of polymorphisms in pfcoronin. No mutations associated with artemisinin resistance were observed in pfk13 or pfcoronin. However, the prevalence of the pfmdr1 N86 and D1246 alleles, that have been associated with decreased susceptibility to lumefantrine, remain high. Although clinical and molecular data suggest that the current malaria treatment guidelines for P. falciparum are presently effective in Pakistan, close monitoring for artemisinin and lumefantrine resistance will be critical to ensure early detection and enhanced containment of emerging ACT resistance spreading across from Southeast Asia.


Assuntos
Antimaláricos/uso terapêutico , Combinação Arteméter e Lumefantrina/uso terapêutico , Marcadores Genéticos , Plasmodium falciparum/genética , Resistência a Medicamentos/genética , Paquistão , Plasmodium falciparum/efeitos dos fármacos
6.
Langmuir ; 35(1): 141-149, 2019 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-30507203

RESUMO

Kinetically controlled self-assembly of block copolymers (BCPs) in solution is an efficient route to fabricate complex hierarchical colloids which are of great importance for nanoencapsulation, microreactors, and biomimics. Herein, segmented wormlike micelles (SWMs) with controllable size are generated by the self-assembly of polystyrene- block-poly(4-vinyl pyridine) in microfluidic channel. Different from the assembly of BCPs off-chip at the same solution properties, it is found that the fabricated SWMs are kinetically controlled assemblies with thermodynamic metastable structures, which are formed by the orderly aggregation of preformed spherical micelles because of the fast mixing process in microfluidic channels. Moreover, by manipulating the total flow velocity of water and BCPs solution or their flow velocity ratio, both of the percentages of SWMs among the whole assemblies and their sizes can be effectively tuned. On the basis of electron microscopy and dynamic light scatting investigations, a product diagram of micellar morphologies associated to initial polymer concentration and flow velocity ratio of water/BCPs solution was constructed, which is important for the rational design and fabrication of complex hierarchical BCP colloids.

7.
Emerg Infect Dis ; 24(1): 159-161, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29260674

RESUMO

During 2013-2015, prevalence of cutaneous leishmaniasis in war-affected Waziristan areas was 3.61% by PCR. Youths (1-15 years of age) were more susceptible. Internal transcribed spacer 1 PCR followed by restriction fragment length polymorphism analysis identified Leishmania tropica in 215 samples and Leishmania major in 6 samples.


Assuntos
Leishmaniose Cutânea/epidemiologia , Adolescente , Criança , Pré-Escolar , Humanos , Lactente , Leishmania major/genética , Leishmania major/isolamento & purificação , Leishmania tropica/genética , Leishmania tropica/isolamento & purificação , Paquistão/epidemiologia , Reação em Cadeia da Polimerase
8.
Microb Pathog ; 102: 160-165, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27914961

RESUMO

Glucose-6-phosphate dehydrogenase (G6PD) is a key enzyme in the pentose phosphate pathway that ensures sufficient production of coenzyme nicotinamide adenine dinucleotide phosphate (NADPH) by catalyzing the reduction of NADP+ to NADPH. Noteworthy, the latter mediates the production of reactive oxygen species (ROS) by phagocytic cells such as neutrophils and monocytes. Therefore, patients with severe forms of G6PD deficiency may present impaired NADPH oxidase activity and become susceptible to recurrent infections. This fact, highlights the importance to characterize the immunopathologic mechanisms underlying the susceptibility to infections in patients with G6PD deficiency. Here we report the first two cases of G6PD deficiency with Bacille Calmette-Guérin (BCG) adverse effect, besides jaundice, hemolytic anemia and recurrent infections caused by Staphylococcus aureus. The qualitative G6PD screening was performed and followed by oxidative burst analysis using flow cytometry. Genetic and in silico analyses were carried out by Sanger sequencing and mutation pathogenicity predicted using bioinformatics tools, respectively. Activated neutrophils and monocytes from patients displayed impaired oxidative burst. The genetic analysis revealed the novel missense mutation c.1157T>A/p.L386Q in G6PD. In addition, in silico analysis indicated that this mutation is pathogenic, thereby hampering the oxidative burst of neutrophils and monocytes from patients. Our data expand the clinical and genetic spectrum of G6PD deficiency, and suggest that impaired oxidative burst in this severe primary immune deficiency is an underlying immunopathologic mechanism that predisposes to mycobacterial infections.


Assuntos
Deficiência de Glucosefosfato Desidrogenase/diagnóstico , Deficiência de Glucosefosfato Desidrogenase/genética , Glucosefosfato Desidrogenase/genética , Substituição de Aminoácidos , Vacina BCG/efeitos adversos , Análise Mutacional de DNA , Estudos de Associação Genética , Glucosefosfato Desidrogenase/química , Deficiência de Glucosefosfato Desidrogenase/complicações , Deficiência de Glucosefosfato Desidrogenase/imunologia , Humanos , Masculino , Modelos Moleculares , Monócitos/imunologia , Monócitos/metabolismo , Mutação de Sentido Incorreto , Mycobacterium bovis , Neutrófilos/imunologia , Neutrófilos/metabolismo , Estresse Oxidativo , Linhagem , Conformação Proteica , Espécies Reativas de Oxigênio/metabolismo , Explosão Respiratória
9.
Microb Pathog ; 95: 82-85, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27032999

RESUMO

Tuberculosis is a global health problem, and its early diagnosis is the ultimate strategy for prevention and control. The current study was undertaken to evaluate conventional and molecular diagnostic assays for the detection of mycobacteria in pulmonary tuberculosis (TB) patients from Khyber Pakhtunkhwa region of Pakistan. A total of 259 clinically suspected patients of TB were processed for Zeihl Neelsen (ZN) microscopy, BACTEC MGIT liquid culture and GeneXpert assay. Among 259 samples, 28 (10.81%) were positive for acid fast bacilli (AFB) on ZN microscopy. In liquid culture, the growth of mycobacterium species was obtained in 36 (13.89%) samples while the GeneXpert assay detected Mycobacterium tuberculosis (MTB) in 49 (18.91%) samples. Detection rate of MTB was significantly high (n = 49, p < 0.0095) on GeneXpert as compared to microscopy (n = 28); however no significant difference (p = 0.1230) was observed on GeneXpert (n = 49) and culture (n = 36) based detection of MTB. The strength of agreement between GeneXpert and microscopy was also poor (Kappa value < 0.114, 95% CI: -0.72 - 0.301) which support our results. MTB detection rate among female was high as compared to male TB patients while in age wise, the age group 55-64 years has almost high detection rate on microscopy, culture and GeneXpert assay. Findings of the present study highlighted that GeneXpert is more efficient tool for timely diagnosis and proper TB control in high TB endemic area.


Assuntos
Técnicas de Diagnóstico Molecular/métodos , Mycobacterium tuberculosis/isolamento & purificação , Escarro/microbiologia , Tuberculose Pulmonar/diagnóstico , Diagnóstico Precoce , Feminino , Humanos , Masculino , Técnicas Microbiológicas/métodos , Microscopia/métodos , Mycobacterium tuberculosis/genética , Paquistão , Fatores de Tempo
10.
Microb Pathog ; 100: 163-169, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27666509

RESUMO

Chronic granulomatous disease (CGD) is a primary immunodeficiency caused by mutations in the five structural genes (CYBB, CYBA, NCF1, NCF2, and NCF4) that typically results in a decrease in function or inability to generate a respiratory burst, leading to defective killing of pathogens, including fungi and intracellular bacteria. Mutations in CYBB, encoding the gp91phox (also known as NOX2) result in X-linked CGD account for approximately 65% of CGD cases. Here, we aimed the characterization of a novel missense mutation c.1226C > A/p.A409E in the CYBB gene in a patient with X-linked CGD. Relevant clinical data of a male patient whose family was positive for XCGD was reviewed. Oxidative burst and NADPH protein expression was evaluated by flow cytometry, while Genetic analysis was performed by Sanger sequencing. Monocyte-derived macrophages (MDMs) were evaluated for their capacity for phagocytosis and growth suppression of the intracellular Mycobacterium tuberculosis (M. tuberculosis). We thus report the absence of an oxidative burst in the phagocytes of the patient. Flow cytometry evaluation revealed a normal expression of NADPH oxidase components in neutrophils and genetic analysis proved the existence of a novel missense c.1226C > A mutation in the CYBB gene resulting in p.A409E. Further, we have showed that the patient's MDMs were unhindered in their ability to take up mycobacteria normally. Instead, the MDMs failed to control the intracellular proliferation of M. tuberculosis, a phenotype that improved in the presence of recombinant human interferon-gamma (rhIFN-γ). This work expands the genetic spectrum of X-linked CGD and demonstrates improvement in macrophage function in X91+CGD patient by rhIFN-γ.


Assuntos
Doenças Transmissíveis/imunologia , Predisposição Genética para Doença , Doença Granulomatosa Crônica/imunologia , Glicoproteínas de Membrana/genética , Mutação de Sentido Incorreto , NADPH Oxidases/análise , Células Cultivadas , Doenças Transmissíveis/genética , Citometria de Fluxo , Doença Granulomatosa Crônica/genética , Humanos , Macrófagos/imunologia , Masculino , Mycobacterium tuberculosis/crescimento & desenvolvimento , Mycobacterium tuberculosis/imunologia , NADPH Oxidase 2 , NADPH Oxidases/genética , Fagocitose , Explosão Respiratória , Análise de Sequência de DNA
11.
Langmuir ; 32(32): 8238-44, 2016 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-27466062

RESUMO

The presence of surfaces influences the kinetics of amyloid-ß (Aß) peptide fibrillation. Although it has been generally recognized that the fibrillation process can be assisted or accelerated by surface chemistry, the impact of surface topography, i.e., roughness, on peptide fibrillation is relatively little understood. Here we study the role of surface roughness on surface-mediated fibrillation using polymer coatings of varying roughness as well as polymer microparticles. Using single-molecule tracking, atomic force microscopy, and the thioflavin T fluorescence technique, we show that a rough surface decelerates the two-dimensional (2D) diffusion of peptides and retards the surface-mediated fibrillation. A higher degree of roughness that presents an obstacle to peptide diffusion is found to inhibit the fibrillation process.


Assuntos
Peptídeos beta-Amiloides/química , Tiazóis/química , Benzotiazóis , Humanos , Microscopia de Força Atômica , Propriedades de Superfície
13.
J Biomol Struct Dyn ; : 1-15, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38319072

RESUMO

In the present investigation, the role of GS-AgNPs treatment in wheat plants was carried out in reducing heat stress with the aim of facilitating scientists on this topic. The effect of GS-AgNPs against heat stress has rarely been deliberated in wheat plants, and only a few studies have been established earlier in this scenario. This work illustrated the effect of GS-AgNPs on the regulation of carbohydrates metabolism, SOD, proteins, crude fibers, and minerals changes in wheat plants. Data were analysed using PCA analysis, correlation parameters, and normal probability distribution in PAST 3 software. The results indicated that heat stress alone caused severe changes in carbohydrates metabolism, SOD, proteins, crude fibers, and minerals immediately so that plants could not recover without foreign stabilizers such as GS-AgNPs. The application of GS-AgNPs increases the flux of carbohydrates metabolism, SOD, and proteins, including HSPs, crude fibers, and minerals, in wheat plants to reduce the effect of heat stress. The 50 mg/l concentration of GS-AgNPs has shown an increase in carbohydrates metabolism and SOD activity, while crude fibres have shown a significant enhancement at 100 mg/l of GS-AgNPs. The crude and true proteins were also shown pronounced increase in treatment to a concentration of 50 mg/l of GS-AgNPs. GS-AgNPs stimulated HSP production; most importantly, smHSP production was observed in the present results with other HSPs in wheat plants treated with a 50 mg/l concentration of GS-AgNPs. The mineral distribution was also regulated by the respective treatment of GS-AgNPs, and the highest amounts of Ca, P and Fe were found to be highest in wheat under heat stress. In general, we computed the expected model based on GS-AgNPs on the genes/factors that respond to heat stress and their potential role in mitigating heat stress in wheat. In addition, we discussed the prospective signalling pathway triggered by GS-AgNPs in wheat against heat stress. In the future, this work might be helpful in distinguishing the genetic variation due to GS-AgNPs in promoting tolerance in wheat against heat stress.Communicated by Ramaswamy H. Sarma.

14.
Biomicrofluidics ; 18(3): 031505, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38855476

RESUMO

Rapid identification of pathogens with higher sensitivity and specificity plays a significant role in maintaining public health, environmental monitoring, controlling food quality, and clinical diagnostics. Different methods have been widely used in food testing laboratories, quality control departments in food companies, hospitals, and clinical settings to identify pathogens. Some limitations in current pathogens detection methods are time-consuming, expensive, and laborious sample preparation, making it unsuitable for rapid detection. Microfluidics has emerged as a promising technology for biosensing applications due to its ability to precisely manipulate small volumes of fluids. Microfluidics platforms combined with spectroscopic techniques are capable of developing miniaturized devices that can detect and quantify pathogenic samples. The review focuses on the advancements in microfluidic devices integrated with spectroscopic methods for detecting bacterial microbes over the past five years. The review is based on several spectroscopic techniques, including fluorescence detection, surface-enhanced Raman scattering, and dynamic light scattering methods coupled with microfluidic platforms. The key detection principles of different approaches were discussed and summarized. Finally, the future possible directions and challenges in microfluidic-based spectroscopy for isolating and detecting pathogens using the latest innovations were also discussed.

15.
Cureus ; 16(4): e59248, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38813271

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal cancer often diagnosed at advanced stages, highlighting the urgent need for early detection strategies. This systematic review explores the potential of fecal and urinary biomarkers for early PDAC detection. A comprehensive search identified eight relevant studies investigating various biomarkers, including proteins, metabolites, microbial profiles, DNA mutations, and non-coding RNAs. Promising findings suggest that urinary biomarkers related to metabolic alterations, inflammatory processes, fecal microbiome profiles, and fecal miRNAs hold diagnostic potential even at early stages of PDAC. Combining biomarkers into panels may enhance diagnostic accuracy. Challenges such as validation in larger cohorts, standardization of protocols, and regulatory approval must be addressed for clinical translation. Despite these hurdles, non-invasive urinary and fecal biomarkers represent a promising avenue for improving PDAC outcomes through early detection.

16.
Future Microbiol ; 18: 795-807, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37650688

RESUMO

Aim: The current research aims to design effective strategies to enhance the body's immune system against pathogenic bacteria. Methods: Skin commensals were isolated, identified and cultured in fish collagen peptides (FCPs). Results: After culturing in FCP, the skin commensals were used in a dose-dependent manner for Staphylococcus aureus in a dual-culture test, which showed significant growth inhibition of the pathogenic bacteria, which concluded that FCP induced the immune defense system of skin microbiota against pathogenic strains. Conclusion: Results have validated that fish collagen peptide plays a vital role in the growth of selected human skin flora and induces more defensive immunity against pathogenic S. aureus bacteria in dual-culture experimentation.


Assuntos
Microbiota , Infecções Estafilocócicas , Animais , Humanos , Staphylococcus aureus , Pele/microbiologia , Infecções Estafilocócicas/microbiologia , Peptídeos/farmacologia , Bactérias , Colágeno/farmacologia , Staphylococcus epidermidis
17.
Spectrochim Acta A Mol Biomol Spectrosc ; 288: 122206, 2023 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-36481538

RESUMO

Pseudomonas aeruginosa is an opportunist pathogen responsible for causing several infections in the human body, especially in patients with weak immune systems. The proposed approach reports a novel pathogens detection system based on cultivating microdroplets and acquiring the scattered light signals from the incubated droplets using a microfluidic device. Initially, the microdroplets were generated and incubated to cultivate bacteria inside the microdroplets. The second part of the microfluidic chip is the detection module, embedded with three optical fibers to connect laser light and photosensors. The incubated droplets were reinjected in the detection module and passed through the laser light. The surrounding photosensors were arranged symmetrically at 45° to the flowing channel for acquiring the scattered light signal. The noise was removed from the acquired data, and time-domain waveform features were evaluated. The acquired features were trained using machine learning classifiers to classify P. aeruginosa. The k-nearest neighbors (KNN) showed superior classification performance with 95.6 % accuracy among other classifiers, including logistic regression (LR), support vector machines (SVM), and naïve Bayes (NB). The proposed research was performed to validate the method for pathogens detection with a concentration of 105 CFU/mL. The total duration of 6 h is required to test the sample, including five hours for droplets incubation and one hour for sample preparation and detection using light scattering module. The results indicate that acquiring the light scattering patterns from incubated droplets can detect P. aeruginosa using machine learning classification. The proposed system is anticipated to be helpful as a rapid device for diagnosing pathogenic infections.


Assuntos
Microfluídica , Pseudomonas aeruginosa , Humanos , Teorema de Bayes , Aprendizado de Máquina , Máquina de Vetores de Suporte , Análise Espectral , Lasers
18.
ACS Biomater Sci Eng ; 8(4): 1367-1380, 2022 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-35266709

RESUMO

Additive manufacturing is an advanced manufacturing manner that seems like the industrial revolution. It has the inborn benefit of producing complex formations, which are distinct from traditional machining technology. Its manufacturing strategy is flexible, including a wide range of materials, and its manufacturing cycle is short. Additive manufacturing techniques are progressively used in bone research and orthopedic operation as more innovative materials are developed. This Review lists the recent research results, analyzes the strengths and weaknesses of diverse three-dimensional printing strategies in orthopedics, and sums up the use of varying 3D printing strategies in surgical guides, surgical implants, surgical predictive models, and bone tissue engineering. Moreover, various postprocessing methods for additive manufacturing for orthopedics are described.


Assuntos
Ortopedia , Impressão Tridimensional , Engenharia Tecidual
19.
Anal Chim Acta ; 1189: 339223, 2022 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-34815054

RESUMO

The rapid detection of the pathogenic bacteria in patient samples is crucial to expedient patient care. The proposed approach reports the development of a novel lab-on-a-chip device for the rapid detection of P. aeruginosa based on immunomagnetic separation, optical scattering, and machine learning. The immunomagnetic particles with a diameter of 5 µm were synthesized for isolating P. aeruginosa from the test sample. A microfluidic chip was fabricated, and three optical fibers were embedded for connecting a laser light and two photodetectors. The laser light was pointed towards the channel to pass light through the sample. A pair of photodetectors via optical fibers were arranged symmetrically at 45° to the channel. The photodetectors acquired scattered light from the flowing sample and converted the light to an electrical signal. The sample containing immunomagnetic beads linked with bacteria was injected into the microfluidic chip. The optimized conditions for performing the experiments were characterized for real-time detection of P. aeruginosa. The data acquisition system recorded the real-time light scattering from the test sample. After removing noise from the output waveform, five different time-domain statistical features were extracted from each waveform: standard mean, standard variance, skewness, kurtosis, and coefficient of variation. The pathogens classification was performed by training the discrimination model using extracted features based on machine learning algorithms. The support vector machines (SVM) with a sigmoid function kernel showed superior classification performance with 97.9% accuracy among other classifiers, including k-nearest neighbors (KNN), logistic regression (LR), and naïve Bayes (NB). The method can detect P. aeruginosa specifically and quantitatively with a limit of detection of 102 CFU/mL. The device can classify P. aeruginosa within 10 min with a total assay time of 25 min. The device was used to test its ability to detect pathogen from the serum and sputum specimens spiked with 105 CFU/mL concentration of P. aeruginosa. The results indicate that light scattering combined with machine learning can be used to detect P. aeruginosa. The proposed technique is anticipated to be helpful as a rapid device for diagnosing P. aeruginosa related infections.


Assuntos
Dispositivos Lab-On-A-Chip , Pseudomonas aeruginosa , Teorema de Bayes , Humanos , Separação Imunomagnética , Aprendizado de Máquina , Máquina de Vetores de Suporte
20.
Front Bioeng Biotechnol ; 10: 1097363, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36588961

RESUMO

The rapid classification of micro-particles has a vast range of applications in biomedical sciences and technology. In the given study, a prototype has been developed for the rapid detection of particle size using multi-angle dynamic light scattering and a machine learning approach by applying a support vector machine. The device consisted of three major parts: a laser light, an assembly of twelve sensors, and a data acquisition system. The laser light with a wavelength of 660 nm was directed towards the prepared sample. The twelve different photosensors were arranged symmetrically surrounding the testing sample to acquire the scattered light. The position of the photosensor was based on the Mie scattering theory to detect the maximum light scattering. In this study, three different spherical microparticles with sizes of 1, 2, and 4 µm were analyzed for the classification. The real-time light scattering signals were collected from each sample for 30 min. The power spectrum feature was evaluated from the acquired waveforms, and then recursive feature elimination was utilized to filter the features with the highest correlation. The machine learning classifiers were trained using the features with optimum conditions and the classification accuracies were evaluated. The results showed higher classification accuracies of 94.41%, 94.20%, and 96.12% for the particle sizes of 1, 2, and 4 µm, respectively. The given method depicted an overall classification accuracy of 95.38%. The acquired results showed that the developed system can detect microparticles within the range of 1-4 µm, with detection limit of 0.025 mg/ml. Therefore, the current study validated the performance of the device, and the given technique can be further applied in clinical applications for the detection of microbial particles.

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