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1.
Access Microbiol ; 6(3)2024.
Artigo em Inglês | MEDLINE | ID: mdl-38725590

RESUMO

Introduction. Brucellosis, a globally distributed zoonotic disease, is caused by the Gram-negative bacteria known as Brucella. Humans acquire infection through direct contact with the blood, urine and placenta of animals, inhalation of dust or aerosols at infected animal farms, and raw milk and meat intake. This study aimed to assess the prevalence of brucellosis in dairy farmers in and around the Aligarh region of North India, to document various clinical signs and symptoms in Brucella-positive individuals, and to create awareness in dairy farmers concerning brucellosis and ways to prevent it. Methods. This was an observational study that included 125 dairy farmers in and around the Aligarh region. Serum samples were taken from this high-risk group after obtaining informed consent. Further, a pre-designed proforma was used to collect information about their knowledge, attitude and practices (KAP) concerning brucellosis and assess the risk factors for the disease. The Rose Bengal test (RBT), serum agglutination test (SAT) and enzyme-linked immunosorbent assay (ELISA) were performed to detect the seroprevalence of brucellosis. Result.Brucella infection was diagnosed in 64 (51.20 %) cases by indirect ELISA (IgM+IgG), 41 (32.8 %) by RBT and 4 (3.2 %) by SAT. Significant clustering of patients was seen in the 20-55 years age group. The most common symptoms in ELISA IgM-positive patients were joint pain (16.07 %), fatigue (14.28 %), anorexia (12.50 %), weight loss (8.92 %), malaise (5.35 %), undulant fever (3.57 %), night sweats (3.57 %) and headache (1.78 %). The findings of this study indicate that ELISA (IgM+IgG) exhibits great sensitivity as compared to SAT and RBT. KAP was very poor among dairy farmers. Conclusion. In India, Brucella is a frequent but severely underreported illness. ELISA is the most sensitive serological test for diagnosing brucellosis. No potential vaccine has yet been introduced for humans against brucellosis. Thus, it is necessary to impart awareness and sensitize high-risk groups concerning brucellosis.

2.
Microsc Res Tech ; 87(1): 133-148, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37728140

RESUMO

The emergence of multidrug resistance (MDR) in bacterial pathogens is a serious public health concern. A significant therapeutic target for MDR infections is the quorum sensing-regulated bacterial pathogenicity. Determining the anti-quorum sensing abilities of certain medicinal plants against bacterial pathogens as well as the in-silico interactions of particular bioactive phytocompounds with QS and biofilm-associated proteins were the objectives of the present study. In this study, 6 medicinal plants were selected based on their ethnopharmacological usage, screened for Anti-QS activity and Artemisia annua leaf extract (AALE) demonstrated pigment inhibitory activity against Chromobacterium violaceum CV12472. Further, the methanol active fraction significantly inhibited the virulence factors (pyocyanin, pyoverdine, rhamnolipid and swarming motility) of Pseudomonas aeruginosa PAO1 and Serratia marcescens MTCC 97 at respective sub-MICs. The inhibition of biofilm was determined using a microtiter plate test and scanning electron microscopy. Biofilm formation was impaired by 70%, 72% and 74% in P. aeruginosa, C. violaceum and S. marcescens, respectively at 0.5xMIC of the extract. The phytochemical content of the extract was studied using GC-MS and 1, 8-cineole was identified as major bioactive compound. Furthermore, 1, 8-cineole was docked with quorum sensing (QS) proteins (LasI, LasR, CviR, and rhlR) and biofilm proteins (PilY1 and PilT). In silico docking and dynamics simulations studies suggested interactions with QS-receptors CviR', LasI, LasR, and biofilm proteins PilY1, PilT for anti-QS activity. Further, 1, 8-cineole demonstrated 66% and 51% reduction in violacein production and biofilm formation, respectively to validate the findings of computational analysis. Findings of the present investigation suggests that 1, 8-cineole plays a crucial role in the QS and biofilm inhibitory activity demonstrated by Artemisia annua extract. RESEARCH HIGHLIGHTS: Artemisia annua leaf extract (AALE) methanol fraction demonstrated broad-spectrum QS and biofilm inhibition Scanning electron microscopy (SEM) confirmed biofilm inhibition Molecular docking and simulation studies suggested positive interactions of 1,8-cineol with QS-receptors and biofilm proteins.


Assuntos
Artemisia annua , Plantas Medicinais , Percepção de Quorum , Virulência , Eucaliptol/farmacologia , Plantas Medicinais/química , Artemisia annua/metabolismo , Simulação de Acoplamento Molecular , Metanol/farmacologia , Antibacterianos/química , Biofilmes , Extratos Vegetais/farmacologia , Bactérias
3.
J Family Med Prim Care ; 12(10): 2385-2391, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38074239

RESUMO

Background: SARS-CoV-causing COVID-19 resulted in mortality, and the clinic-epidemiological profile at the time of admission of patients who died later could provide an insight into pathophysiological consequences due to infection. Method: Retrospective observational study of 64 RTPCR-confirmed COVID-19 non-survivors was conducted from April - June 2021 and January February 2022. Data were analyzed, and a P value<0.05 was taken as significant. Results: 60.94% and 39.06 % were males and females, and 26.57% & 73.43 % of patients had moderate and severe disease, respectively. Fever, cough, and dyspnea were the most common presenting symptoms. 78.12% and 21.88% had pre-existing (diabetes and hypertension were most common) and no co-morbidities, respectively. 65.62 & 17.19 % of patients had bilateral and unilateral ground glass opacities, respectively. Thrombocytopenia, lymphopenia, neutrophilia, elevated monocytes, and neutrophil-lymphocyte ratio (NLR) of 7.52 were hematological findings. D dimer was elevated. ABG showed low PaO2 and SPO2 %. ALT and AST were elevated. Tachycardia was also present. Compared to the first wave, no significant association of gender with severity was found. However, the percentage of male patients was higher. The association of the duration of stay and co-morbidity with disease severity was significant in both the first and subsequent waves of COVID-19. Conclusion: Co-morbidity, disease severity, and radiological lung opacities play a role in the outcome of COVID-19. The associated findings are hematological, renal, liver, cardiovascular, and arterial blood gas derangements.

4.
PLoS One ; 18(12): e0295524, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38113217

RESUMO

The quorum sensing mechanism relies on the detection and response to chemical signals, termed autoinducers, which regulate the synthesis of virulence factors including toxins, enzymes, and biofilms. Emerging therapeutic strategies for infection control encompass approaches that attenuate quorum-sensing systems. In this study, we evaluated the antibacterial, anti-quorum sensing, and anti-biofilm activities of Psidium guajava L. methanolic leaf extracts (PGME). Minimum Inhibitory Concentrations (MICs) of PGME were determined as 500 µg/ml for C. violaceum and 1000 µg/ml for P. aeruginosa PAO1. Significantly, even at sub-MIC concentrations, PGME exhibited noteworthy anti-quorum sensing properties, as evidenced by concentration-dependent inhibition of pigment production in C. violaceum 12742. Furthermore, PGME effectively suppressed quorum-sensing controlled virulence factors in P. aeruginosa PAO1, including biofilm formation, pyoverdin, pyocyanin, and rhamnolipid production, with concentration-dependent inhibitory effects. Phytochemical analysis utilizing GC-MS revealed the presence of compounds such as alpha-copaene, caryophyllene, and nerolidol. In-silico docking studies indicated a plausible mechanism for the observed anti-quorum sensing activity, involving favorable binding and interactions with QS-receptors, including RhlR, CviR', LasI, and LasR proteins. These interactions were found to potentially disrupt QS pathways through suppression of AHL production and receptor protein blockade. Collectively, our findings propose PGME as a promising candidate for the treatment of bacterial infections. Its attributes that mitigate biofilm development and impede quorum-sensing mechanisms highlight its potential therapeutic value.


Assuntos
Psidium , Percepção de Quorum , Psidium/metabolismo , Biofilmes , Fatores de Virulência/metabolismo , Antibacterianos/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Pseudomonas aeruginosa
5.
Front Mol Biosci ; 10: 1292509, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37965379

RESUMO

Infectious diseases remain among the most pressing concerns for human health. This issue has grown even more complex with the emergence of multidrug-resistant (MDR) bacteria. To address bacterial infections, nanoparticles have emerged as a promising avenue, offering the potential to target bacteria at multiple levels and effectively eliminate them. In this study, silver nanoparticles (AA-AgNPs) were synthesized using the leaf extract of a medicinal plant, Abroma augusta. The synthesis method is straightforward, safe, cost-effective, and environment friendly, utilizing the leaf extract of this Ayurvedic herb. The UV-vis absorbance peak at 424 nm indicated the formation of AA-AgNPs, with the involvement of numerous functional groups in the synthesis and stabilization of the particles. AA-AgNPs exhibited robust antibacterial and antibiofilm activities against methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococci (VRE). The MIC values of AA-AgNPs ranged from 8 to 32 µg/mL. Electron microscopic examination of the interaction of AA-AgNPs with the test bacterial pathogens showed a deleterious impact on bacterial morphology, resulting from membrane rupture and leakage of intracellular components. AA-AgNPs also demonstrated a dose-dependent effect in curtailing biofilm formation below inhibitory doses. Overall, this study highlights the potential of AA-AgNPs in the successful inhibition of both the growth and biofilms of MRSA and VRE bacteria. Following studies on toxicity and dose optimization, such AgNPs could be developed into effective medical remedies against infections.

6.
Iran J Microbiol ; 15(2): 181-188, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37193231

RESUMO

Background and Objectives: There are conflicting views regarding face mask guidelines amongst healthcare staff to prevent transmission of coronavirus disease 2019 (COVID-19), influenza and other respiratory viral infections (RVIs). We conducted a thorough meta-analysis to statistically compare mask use versus no mask use efficacy for RVIs in healthcare settings. Materials and Methods: Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines were used for selecting researches published between 2003 and June 2022 from different databases, including Publisher Medline (PubMed), Web of Science, etc.; 6 studies qualified for inclusion. Data was pooled from in vivo randomized control, case-control and observational studies dealing with the relationship between face mask use and no use by patients or health personnel and RVI prevention in healthcare setups. Results: The fixed and random-effects model was carried out to determine pooled odds ratios (ORs) and their respective 95 percent confidence intervals (CIs). The results revealed that wearing a face mask significantly reduced the risk of contracting a respiratory viral illness in hospital settings, with pooled OR (95% CI) of 0.11 (0.04 to 0.33) (probability value (P) <0.08). Conclusion: Masks largely succeeded in stopping respiratory virus transmission, as evidenced by the meta-analysis of 6 studies (a total of 927 individuals).

7.
Biofouling ; 38(7): 715-728, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36062553

RESUMO

Extracts of Centella asiatica leaves (LEs), and in-vitro leaf-calli (CEs), were investigated for antibacterial, antibiofilm, and anti-quorum sensing activities. Ethyl acetate extracts from leaves (EALE), leaf-calli (EACE), methanolic extracts from leaves (MELE), and leaf-calli (MECE) showed antibacterial activity; the minimum inhibitory concentrations (MICs) of LEs and CEs ranged from 0.312-2.50 mg ml-1 and 0.625 - 2.50 mg ml-1, respectively. The MICs of EALE and EACE were 2.50 mg ml-1, each, for C. violaceum 12742, and P. aeruginosa PAO1. At sub-MIC levels, EALE and EACE showed anti-quorum sensing (anti-QS) activity, demonstrated by concentration dependent pigment inhibition of C. violaceum 12742. Similarly, EALE and EACE inhibited QS-controlled virulence factors in P. aeruginosa PAO1 (biofilm, pyocyanin, and pyoverdin); again, the inhibition was concentration-dependent. The best effect was at immediate sub-MIC concentration i.e. 1250 µg ml-1. GC-MS analyses revealed the presence of compound 9,12-Octadecadienoic acid, and in silico docking study suggested interactions with QS-receptors CviR', LasI, and LasR proteins for anti-QS activity.


Assuntos
Incrustação Biológica , Centella , Antibacterianos/farmacologia , Biofilmes , Incrustação Biológica/prevenção & controle , Centella/metabolismo , Ácido Linoleico/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta , Pseudomonas aeruginosa , Piocianina/metabolismo , Fatores de Virulência/metabolismo
8.
Front Microbiol ; 12: 738983, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34707590

RESUMO

SARS-CoV-2-infected patients are reported to show immunocompromised behavior that gives rise to a wide variety of complications due to impaired innate immune response, cytokine storm, and thrombo-inflammation. Prolonged use of steroids, diabetes mellitus, and diabetic ketoacidosis (DKA) are some of the factors responsible for the growth of Mucorales in such immunocompromised patients and, thus, can lead to a life-threatening condition referred to as mucormycosis. Therefore, an early diagnosis and cell-based management cosis is the need of the hour to help affected patients overcome this severe condition. In addition, extended exposure to antifungal drugs/therapeutics is found to initiate hormonal and neurological complications. More recently, mesenchymal stem cells (MSCs) have been used to exhibit immunomodulatory function and proven to be beneficial in a clinical cell-based regenerative approach. The immunomodulation ability of MSCs in mucormycosis patient boosts the immunity by the release of chemotactic proteins. MSC-based therapy in mucormycosis along with the combination of short-term antifungal drugs can be utilized as a prospective approach for mucormycosis treatment with promising outcomes. However, preclinical and in mucormyIn mucormycosis, the hyphae of clinical trials are needed to establish the precise mechanism of MSCs in mucormycosis treatment.

9.
Surg Infect (Larchmt) ; 22(4): 434-441, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33944586

RESUMO

Background: Surgical antimicrobial prophylaxis (SAP) refers to the utilization of antibiotic agents for the prevention of surgical site infections (SSI), to prevent SSI-associated morbidity and mortality, reduce duration and cost of healthcare, and cause minimal adverse drug effects. The adherence rate among surgeons for the available international and national guidelines and optimal practice remains considerably low in many hospitals, especially in developing countries. The objective of this study was to assess the knowledge and compliance rate for SAP guidelines among various surgical specialties and those involved in providing SAP. Methods: An institution-based exploratory, multi-specialty, collective, mixed method approach (qualitative and quantitative) was used to assess the knowledge and compliance rate for SAP guidelines among the consultants and residents of surgical specialties. Quantitative analysis was performed using a pre-tested questionnaire. For qualitative analysis, focus group discussions were conducted. Thematic analysis was conducted by the Theoretical Domains Framework (TDF) and the Capabilities, Opportunities, Motivation and Behaviour (COM-B) model. Results: Twenty-eight focus groups and 16 paired interviews were undertaken. On thematic analysis six significant themes were noted and mapped to the COM-B model, and subthemes mapped to the relevant TDF domains in a combined framework. Key themes recognized were: (1) solitary focus on surgical skills; (2) following the hierarchy is more important than guideline compliance; (3) doubts and overcautious attitude of surgeons hinders appropriate SAP prescribing; (4) non-availability in-hospital supply of antimicrobial agents; (5) patient characteristics and type of surgery play a role in prescribing SAP; and (6) lack of national and local guidelines. Conclusions: The knowledge and attitudes of surgeons toward appropriate SAP prescribing are crucial factors for execution of guidelines. Including them in policy making decisions can help in strong execution of the same.


Assuntos
Anti-Infecciosos , Antibioticoprofilaxia , Antibacterianos/uso terapêutico , Anti-Infecciosos/uso terapêutico , Fidelidade a Diretrizes , Hospitais de Ensino , Humanos , Infecção da Ferida Cirúrgica/tratamento farmacológico , Infecção da Ferida Cirúrgica/prevenção & controle , Atenção Terciária à Saúde
10.
Medicina (Kaunas) ; 57(2)2021 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-33673004

RESUMO

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has caused a global pandemic and is posing a serious challenge to mankind. As per the current scenario, there is an urgent need for antiviral that could act as a protective and therapeutic against SARS-CoV-2. Previous studies have shown that SARS-CoV-2 is much similar to the SARS-CoV bat that occurred in 2002-03. Since it is a zoonotic virus, the exact source is still unknown, but it is believed bats may be the primary reservoir of SARS-CoV-2 through which it has been transferred to humans. In this review, we have tried to summarize some of the approaches that could be effective against SARS-CoV-2. Firstly, plants or plant-based products have been effective against different viral diseases, and secondly, plants or plant-based natural products have the minimum adverse effect. We have also highlighted a few vitamins and minerals that could be beneficial against SARS-CoV-2.


Assuntos
Antivirais/uso terapêutico , Produtos Biológicos/uso terapêutico , Tratamento Farmacológico da COVID-19 , Nutrientes/uso terapêutico , SARS-CoV-2/efeitos dos fármacos , Viroses/tratamento farmacológico , Animais , Quirópteros/virologia , Humanos
11.
Antibiotics (Basel) ; 9(5)2020 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-32429514

RESUMO

Synthesis of nanoparticles using the plants has several advantages over other methods due to the environmentally friendly nature of plants. Besides being environmentally friendly, the synthesis of nanoparticles using plants or parts of the plants is also cost effective. The present study focuses on the biosynthesis of zinc oxide nanoparticles (ZnO NPs) using the seed extract of Butea monsoperma and their effect on to the quorum-mediated virulence factors of multidrug-resistant clinical isolates of Pseudomonas aeruginosa at sub minimum inhibitory concentration (MIC). The synthesized ZnO NPs were characterized by different techniques, such as Fourier transform infra-red spectroscopy (FTIR), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), and transmission electron microscopy (TEM). The average size of the nanoparticles was 25 nm as analyzed by TEM. ZnO NPs at sub MIC decreased the production of virulence factors such as pyocyanin, protease and hemolysin for P. aeruginosa (p ≤ 0.05). The interaction of NPs with the P. aeruginosa cells on increasing concentration of NPs at sub MIC levels showed greater accumulation of nanoparticles inside the cells as analyzed by TEM.

12.
Antibiotics (Basel) ; 9(3)2020 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-32120845

RESUMO

Abstract: Plant-based synthesis of eco-friendly nanoparticles has widespread applications in many fields, including medicine. Biofilm-a shield for pathogenic microorganisms-once formed, is difficult to destroy with antibiotics, making the pathogen resistant. Here, we synthesized gold nanoparticles (AuNPs) using the stem of an Ayurvedic medicinal plant, Tinospora cordifolia, and studied the action of AuNPs against Pseudomonas aeruginosa PAO1 biofilm. The synthesized AuNPs were characterized by techniques such as ultraviolet-visible spectroscopy, Fourier-transform infrared (FTIR) spectroscopy, energy-dispersive X-ray diffraction, X-ray diffraction, scanning electron microscopy (SEM), and transmission electron microscopy. The AuNPs were spherically shaped with an average size of 16.1 nm. Further, the subminimum inhibitory concentrations (MICs) of AuNPs (50, 100, and 150 µg/mL) greatly affected the biofilm-forming ability of P. aeruginosa, as observed by crystal violet assay and SEM, which showed a decrease in the number of biofilm-forming cells with increasing AuNP concentration. This was further justified by confocal laser scanning microscopy (CLSM), which showed irregularities in the structure of the biofilm at the sub-MIC of AuNPs. Further, the interaction of AuNPs with PAO1 at the highest sub-MIC (150 µg/mL) showed the internalization of the nanoparticles, probably affecting the tendency of PAO1 to colonize on the surface of the nanoparticles. This study suggests that green-synthesized AuNPs can be used as effective nano-antibiotics against biofilm-related infections caused by P. aeruginosa.

13.
Bioinorg Chem Appl ; 2019: 4649506, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31354799

RESUMO

Development of multidrug resistance among pathogens has become a global problem for chemotherapy of bacterial infections. Extended-spectrum ß-lactamase- (ESßL-) producing enteric bacteria and methicillin-resistant Staphylococcus aureus (MRSA) are the two major groups of problematic MDR bacteria that have evolved rapidly in the recent past. In this study, the aqueous extract of Murraya koenigii leaves was used for synthesis of silver nanoparticles. The synthesized MK-AgNPs were characterized using UV-vis spectroscopy, FTIR, XRD, SEM, and TEM, and their antibacterial potential was evaluated on multiple ESßL-producing enteric bacteria and MRSA. The nanoparticles were predominantly found to be spheroidal with particle size distribution in the range of 5-20 nm. There was 60.86% silver content in MK-AgNPs. Evaluation of antibacterial activity by the disc-diffusion assay revealed that MK-AgNPs effectively inhibited the growth of test pathogens with varying sized zones of inhibition. The MICs of MK-AgNPs against both MRSA and methicillin-sensitive S. aureus (MSSA) strains were 32 µg/ml, while for ESßL-producing E. coli, it ranged from 32 to 64 µg/ml. The control strain of E. coli (ECS) was relatively more sensitive with an MIC of 16 µg/ml. The MBCs were in accordance with the respective MICs. Analysis of growth kinetics revealed that the growth of all tested S. aureus strains was inhibited (∼90%) in presence of 32 µg/ml of MK-AgNPs. The sensitive strain of E. coli (ECS) showed least resistance to MK-AgNPs with >81% inhibition at 16 µg/ml. The present investigation revealed an encouraging result on in vitro efficacy of green synthesized MK-AgNPs and needed further in vivo assessment for its therapeutic efficacy against MDR bacteria.

14.
Int J Nanomedicine ; 14: 4667-4679, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31308652

RESUMO

Purpose: The pathogenicity in Candida spp was attributed by several virulence factors such as production of tissue damaging extracellular enzymes, germ tube formation, hyphal morphogenesis and establishment of drug resistant biofilm. The objective of present study was to investigate the effects of silver nanoparticles (AgNPs) on growth, cell morphology and key virulence attributes of Candida species. Methods: AgNPs were synthesized by the using seed extract of Syzygium cumini (Sc), and were characterized by UV-Vis spectrophotometer, Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), and transmission electron microscopy (TEM). ScAgNPs were used to evaluate their antifungal and antibacterial activity as well as their potent inhibitory effects on germ tube and biofilm formation and extracellular enzymes viz. phospholipases, proteinases, lipases and hemolysin secreted by Candida spp. Results: The MICs values of ScAgNPs were ranged from 0.125-0.250 mg/ml, whereas the MBCs and MFCs were 0.250 and 0.500 mg/ml, respectively. ScAgNPs significantly inhibit the production of phospholipases by 82.2, 75.7, 78.7, 62.5, and 65.8%; proteinases by 82.0, 72.0, 77.5, 67.0, and 83.7%; lipase by 69.4, 58.8, 60.0, 42.9, and 65.0%; and hemolysin by 62.8, 69.7, 67.2, 73.1, and 70.2% in C. albicans, C. tropicalis, C. dubliniensis, C. parapsilosis and C. krusei, respectively, at 500 µg/ml. ScAgNPs inhibit germ tube formation in C. albicans up to 97.1% at 0.25 mg/ml. LIVE/DEAD staining results showed that ScAgNPs almost completely inhibit biofilm formation in C. albicans. TEM analysis shows that ScAgNPs not only anchored onto the cell surface but also penetrated and accumulated in the cytoplasm that causes severe damage to the cell wall and cytoplasmic membrane. Conclusion: To summarize, the biosynthesized ScAgNPs strongly suppressed the multiplication, germ tube and biofilm formation and most importantly secretion of hydrolytic enzymes (viz. phospholipases, proteinases, lipases and hemolysin) by Candia spp. The present research work open several avenues of further study, such as to explore the molecular mechanism of inhibition of germ tubes and biofilm formation and suppression of production of various hydrolytic enzymes by Candida spp.


Assuntos
Antifúngicos/farmacologia , Candida/crescimento & desenvolvimento , Candida/patogenicidade , Nanopartículas Metálicas/química , Prata/farmacologia , Antifúngicos/química , Biofilmes/efeitos dos fármacos , Candida/citologia , Candida/efeitos dos fármacos , Parede Celular/efeitos dos fármacos , Proteínas Hemolisinas/metabolismo , Humanos , Hidrólise , Nanopartículas Metálicas/ultraestrutura , Testes de Sensibilidade Microbiana , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Syzygium/química , Virulência/efeitos dos fármacos , Fatores de Virulência
15.
J Glob Infect Dis ; 10(3): 133-139, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30166812

RESUMO

OBJECTIVES: Detection and comparison of metallo-ß-lactamase (MBL) production in clinical isolates by phenotypic and genotypic measures. The objective of this study is to evaluate clinical characteristics and risk factors in patients infected with MBLs. MATERIALS AND METHODS: Study was conducted by the Department of Microbiology, Jawaharlal Nehru Medical College from February 2014 to December 2015. Bacterial culture, identification, and antibiotic susceptibility were carried out according to standard guidelines. MBL production was detected both phenotypically (Modified Hodge test [MHT], imipenem-ethylene diamine tetraacetic acid double disk potentiation test [IMP-EDTA DDPT], IMP-EDTA combined disk synergy test [IMP-EDTA CDST]), and genotypically (blaNDM-1, blaVIM and blaIMP). RESULTS: Among 116 carbapenem-resistant Gram-negative Bacilli (CRGNB), Citrobacter species 28 (24.1%) was the most common pathogen. Phenotypically, MHT, IMP-EDTA DDPT, and IMP-EDTA CDST detected MBL production in 105 (90.5%), 96 (81%), and 87 (75%) CRGNB, respectively. BlaNDM-1 genes were detected in 6 6 (56.8%) isolates, however, very few blaVIM (16, 15.2%) and blaIMP (1, 1.2%) were identified. Considering polymerase chain reaction (PCR) as the gold standard, it was observed that IMP-EDTA CDST was most specific (78.3%) while MHT was most sensitive (97.4%). Results of blaNDM-1 gene by PCR were further confirmed by sequencing (Triyat genomics, Nagpur). All the 11 representative strains were confirmed to be NDM-1 gene. Major risk factors in patients infected with MBLs were in-dwelling devices (68%), prolonged hospital stay (72%) and prior antibiotic treatment (86%). However, on tracing their outcome, it was interesting to note that mortality was relatively low 5 (4.3%). CONCLUSION: The present study shows a rising trend of blaNDM-1 in CRGNB, an ominous sign heralding the post antibiotic era. It is essential to assess the prevalence of various MBLs so that infection control measures can be reinforced. We recommend three phenotypic tests in tandem for the detection of MBL. While phenotypic tests are easy and cost-effective to perform, quick, effective molecular diagnostic techniques can tailor treatment guidelines to optimize patient's management.

16.
Nanomaterials (Basel) ; 8(8)2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30071582

RESUMO

The objective of the present study was one step extracellular biosynthesis of silver nanoparticles (AgNPs) using supernatant of Candida glabrata isolated from oropharyngeal mucosa of human immunodeficiency virus (HIV) patients and evaluation of their antibacterial and antifungal potential against human pathogenic bacteria and fungi. The mycosynthesized AgNPs were characterized by color visualization, ultraviolet-visible (UV) spectroscopy, fourier transform infrared spectroscopy (FTIR), and transmission electron microscopy (TEM). The FTIR spectra revealed the binding and stabilization of nanoparticles with protein. The TEM analysis showed that nanoparticles were well dispersed and predominantly spherical in shape within the size range of 2⁻15 nm. The antibacterial and antifungal potential of AgNPs were characterized by determining minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC)/ minimum fungicidal concentration (MFC), and well diffusion methods. The MBC and MFC were found in the range of 62.5⁻250 µg/mL and 125⁻500 µg/mL, which revealed that bacterial strains were more susceptible to AgNPs than fungal strains. These differences in bactericidal and fungicidal concentrations of the AgNPs were due to the differences in the cell structure and organization of bacteria and yeast cells. The interaction of AgNPs with C. albicans analyzed by TEM showed the penetration of nanoparticles inside the Candida cells, which led the formation of "pits" and "pores" that result from the rupturing of the cell wall and membrane. Further, TEM analysis showed that Candida cells treated with AgNPs were highly deformed and the cells had shrunken to a greater extent because of their interaction with the fungal cell wall and membrane, which disrupted the structure of the cell membrane and inhibited the normal budding process due to the destruction and loss of membrane integrity and formation of pores that may led to the cell death.

17.
Indian J Med Microbiol ; 36(2): 285-288, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30084426

RESUMO

Background: This study attempted to elucidate the spectrum of sexually transmitted infections in a tertiary care centre in North India and to assess the antimicrobial resistance in Neisseria gonorrhoeae. Materials and Methods: Antimicrobial resistance pattern of N. gonorrhoeae was determined by the standard techniques. Genotypic detection of gyrA, parC and blaTEM genes was also carried out. The results of gyrA gene by polymerase chain reaction were confirmed by DNA sequencing. Results: N. gonorrhoea was identified in 10 (4.98%) patients, and antimicrobial sensitivity was performed in seven patients. All the seven patients tested were quinolone-resistant N. gonorrhoeae (QRNG), 5/7 were penicillinase-producing N. gonorrhoeae, 1/7 was chromosomally mediated penicillin-resistant N. gonorrhoeae and 3/7 were tetracycline-resistant N. gonorrhoeae. Minimal inhibitory concentration (MIC) by E-test was performed in five strains, and we observed that MIC90 for ciprofloxacin was ≥4 µg/ml, for penicillin was ≥6 µg/ml and for tetracycline was 12 µg/ml, which clearly brackets them as resistant isolates. The presence of TEM gene was confirmed genotypically in six out of seven cases. In all seven cases, gyrA and parC were observed, thus confirming their QRNG status. Conclusion: Alarming increase in the resistance to commonly used antimicrobials for gonorrhoea in our study, especially of fluoroquinolones, is a clarion call for the urgent need for prudence in prescribing them. Observing the rampant resistance exhibited by N. gonorrhoeae, it is clear that the day is not far when it will acquire a superbug status and become intractable to treatment by the available antibiotics.


Assuntos
Antibacterianos/farmacologia , Neisseria gonorrhoeae/efeitos dos fármacos , Ciprofloxacina/farmacologia , DNA Girase/genética , DNA Girase/metabolismo , DNA Topoisomerase IV/genética , DNA Topoisomerase IV/metabolismo , Fluoroquinolonas/farmacologia , Genótipo , Índia , Testes de Sensibilidade Microbiana , Neisseria gonorrhoeae/genética , Centros de Atenção Terciária/estatística & dados numéricos
18.
Indian J Pathol Microbiol ; 61(1): 76-80, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29567888

RESUMO

BACKGROUND: Scrub typhus is lesser known cause of fever of unknown origin in India. Even if there have been reports documenting the prevalence of scrub typhus in different parts of India, it is still an unknown entity, and clinicians usually do not consider it as differential diagnosis. The present study was performed to document the prevalence of scrub typhus among febrile patients in western part of Uttar Pradesh and to assess the clinical profile of infected patients on the one hand and knowledge, attitude, and practices among clinicians on the other. MATERIALS AND METHODS: A total of 357 adult patients with fever of more than 5-day duration were recruited. All patients underwent complete physical examination, and detailed clinical history was elicited as per predesigned pro forma. After primary screening to rule out malaria, enteric fever, and leptospirosis infection, secondary screening for scrub typhus was done by rapid screen test and IgM ELISA. RESULTS: Scrub typhus infection was positive in 91 (25.5%) cases. The most common symptoms among the patients were fever (100%), pain in abdomen (79.1%), pedal edema 56 (61.5%), rash 44 (48.3%), headache 44 (48.3%), vomiting 42 (46.1%), constipation 33 (36.2%), cough 28 (30.7%), and lymphadenopathy 20 (21.9%). The median values of interleukin-8, interferon-gamma, and tumor necrosis factor-alpha in healthy controls were 15.54 pg/ml, 7.77 pg/ml, and 54.1 pg/ml, respectively, while the median values of these cytokines in scrub typhus-positive patients were 21.04 pg/ml, 8.74 pg/ml, and 73.8 pg/ml, respectively. CONCLUSION: Our results highlight that scrub typhus infection is an important cause of pyrexia of unknown origin, and active surveillance is necessary to assess the exact magnitude and distribution of the disease.


Assuntos
Febre/imunologia , Interferon gama/sangue , Interleucina-8/sangue , Tifo por Ácaros/epidemiologia , Tifo por Ácaros/imunologia , Fator de Necrose Tumoral alfa/sangue , Adulto , Anticorpos Antibacterianos/sangue , Ensaio de Imunoadsorção Enzimática , Feminino , Febre/epidemiologia , Febre/etiologia , Febre de Causa Desconhecida/diagnóstico , Febre de Causa Desconhecida/epidemiologia , Febre de Causa Desconhecida/imunologia , Febre de Causa Desconhecida/parasitologia , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Orientia tsutsugamushi/imunologia , Orientia tsutsugamushi/isolamento & purificação , Médicos/psicologia , Médicos/estatística & dados numéricos , Prevalência , Tifo por Ácaros/sangue , Tifo por Ácaros/diagnóstico
19.
Artif Cells Nanomed Biotechnol ; 46(sup1): 912-925, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29446992

RESUMO

The pathogenicity of Candida species in human is dependent on a variety of virulence factor such as adhesion factors, germ tube and hyphal formation, secretion of hydrolytic phospholipases and proteinases and drug resistance biofilm. ZnO NPs have been synthesized by using leaf extract of Crinum latifolium and were characterized by UV-Vis spectrophotometer, FTIR, SEM, EDX and TEM. In this study for the first time, potent inhibitory effects of ZnO NPs on principal virulence factors of Candida albicans and non-albicans such as germ tube formation, secretion of hydrolytic phospholipases and proteinases and biofilm formation has been investigated. ZnO NPs remarkably reduced the germ tube formation of C. albicans at 1 (86.4%), 0.5 (75.0%), 0.25 (61.4%), 0.125 (34.1%) and 0.062 mg/ml (11.4%). ZnO NPs significantly lowered the phospholipase and proteinase secretion by 58.8 and 95.2% at 0.25 mg/ml, respectively. CSLM results showed that ZnO NPs suppressed biofilm formation up to 85% at 0.25 mg/ml. SEM and TEM micrograph showed that ZnO NPs penetrated inside the cell and causes extensive damaged in cell wall and cell membrane. Inhibition of Candida growth and various virulent factors by ZnO NPs provides an insight towards their therapeutic application for the treatment of Candida-associated infections.


Assuntos
Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Candida/efeitos dos fármacos , Nanopartículas/química , Óxido de Zinco/química , Óxido de Zinco/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Candida/citologia , Candida/crescimento & desenvolvimento , Candida/fisiologia , Espaço Extracelular/efeitos dos fármacos , Espaço Extracelular/enzimologia , Hidrólise , Testes de Sensibilidade Microbiana , Virulência/efeitos dos fármacos
20.
In Silico Pharmacol ; 5: 12, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29098138

RESUMO

Pseudomonas aeruginosa an opportunistic pathogen regulates its virulence through Quorum sensing (QS) mechanism comprising of Las and Rhl system. Targeting of QS mechanism could be an ideal strategy to combat infection caused by P. aeruginosa. Silver nanoparticles (AgNPs) have been broadly applied as antimicrobial agents against a number of pathogenic bacterial and fungal strains, but have not been reported as an anti-QS agent. Therefore, the aim of present work was to show the computational analysis for the interaction of AgNPs with the QS system using an In silico approach. In silico studies showed that AgNPs got 'locked' deeply into the active site of respective proteins with their surrounding residues. The molecular docking analysis clearly demonstrated that AgNPs got bound to the catalytic cleft of LasI synthase (Asp73-Ag = 3.1 Å), RhlI synthase (His52-Ag = 2.8 Å), transcriptional receptor protein LasR (Leu159-Ag = 2.3 Å) and RhlR (Trp10-Ag = 3.1 Å and Glu34-Ag = 3.2 Å). The inhibition of LasI/RhlI synthase by AgNPs blocked the biosynthesis of AHLs, thus no AHL produced, no QS occurred. Further, interference with transcriptional regulatory proteins led to the inactivation of LasR/RhlR system that finally blocked the expression of QS-controlled virulence genes. Our findings clearly demonstrate the anti-QS property of AgNPs in P. aeruginosa which could be an alternative approach to the use of traditional antibiotics for the treatment of P. aeruginosa infection.

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