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1.
Eur J Clin Microbiol Infect Dis ; 43(6): 1205-1212, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38557925

RESUMO

Acute encephalitis syndrome (AES) outbreaks in children of Eastern Uttar Pradesh (E-UP) region of India have been a longstanding public health issue, with a significant case fatality rate of 20-25%. Since past decade, a rise in chikungunya (CHIK) cases has been occurring, which is a reported etiology of AES. However, the burden of chikungunya virus (CHIKV) among pediatric AES (pAES) is unknown from E-UP. We included 238 hospitalized pAES cases. The presence of IgM antibodies for CHIKV, and Dengue virus (DENV) was tested, and RT-PCR was performed for CHIKV and DENV in serologically confirmed CHIKV and DENV pAES cases. Positive samples were sequenced using Sangers sequencing. Further, to check for co-infection, IgM antibodies for other AES etiologies including Japanese encephalitis virus (JEV), Leptospira and Orientia tsutsugamushi (OT) in serum were also investigated. IgM ELISA demonstrated 5.04% (12) positivity for CHIKV. Among CHIKV IgM positive, 3 (25%, 3/12) pAES patients died. CHIKV genome was detected in 3 pAES specimens. Among which, 2 CHIKV cases were also positive for OT DNA. Partially sequenced CHIKV were genotyped as ECSA. The overall finding indicates evidence of CHIKV infection with high case fatality among pAES patients from E-UP. This study advocates constant serological and molecular surveillance of CHIKV in AES endemic regions of India.


Assuntos
Encefalopatia Aguda Febril , Anticorpos Antivirais , Febre de Chikungunya , Vírus Chikungunya , Imunoglobulina M , Humanos , Índia/epidemiologia , Febre de Chikungunya/mortalidade , Febre de Chikungunya/epidemiologia , Criança , Masculino , Feminino , Pré-Escolar , Vírus Chikungunya/genética , Vírus Chikungunya/imunologia , Anticorpos Antivirais/sangue , Imunoglobulina M/sangue , Encefalopatia Aguda Febril/epidemiologia , Lactente , Adolescente , Coinfecção/mortalidade , Coinfecção/virologia , Coinfecção/epidemiologia , Vírus da Dengue/genética , Vírus da Dengue/imunologia , Filogenia , Surtos de Doenças
2.
Arch Microbiol ; 205(5): 178, 2023 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-37029825

RESUMO

Scrub typhus (ST) caused by Orientia tsutsugamushi (OT), has long been known to cause acute encephalitis syndrome (AES) and acute febrile illness (AFI). The immunodominant 56 kDa protein of OT, which is encoded by the 56 kDa gene (1600 bp encoding 516-541 amino acids) is a commonly studied antigen for genotype and serotype assignment. Previous studies from India have utilized partial type specific antigen (TSA) 56 kDa sequences for OT strain characterisation. On the other hand, understanding the antigenic diversity of current OT strains, is critical for developing specific diagnostic tests and vaccines against ST. As a result, the current study analyses antigenic variants using the entire TSA56 ORF of OT from AES cases. Phylogenetic investigation using complete TSA56 ORF sequences revealed Karp and Gilliam were the circulating predominant strains of OT. Furthermore, Immuno-informatical analysis demonstrated that the majority of high-binding affinity CD4 TCEs against the most prevalent Indian human leukocyte antigen alleles were present in the S-VDIII/IV and S-VDIV spacer regions of TSA56 ORF. TSA56 conserved spacer is crucial for OT immunological response investigations. Further, the pathophysiological effects of spacer domains in ST require further investigation. Furthermore, the characterization of the TSA56 spacer region of the OT from different parts of India is critical for developing region-specific ST diagnostic assays and vaccines.


Assuntos
Encefalopatia Aguda Febril , Orientia tsutsugamushi , Tifo por Ácaros , Humanos , Orientia tsutsugamushi/genética , Filogenia , Encefalopatia Aguda Febril/genética , Tifo por Ácaros/diagnóstico , Tifo por Ácaros/epidemiologia , Índia
3.
Int J Mol Sci ; 23(11)2022 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35682737

RESUMO

The early management, diagnosis, and treatment of emerging and re-emerging infections and the rising burden of non-communicable diseases (NCDs) are necessary. The Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-Cas system has recently acquired popularity as a diagnostic tool due to its ability to target specific genes. It uses Cas enzymes and a guide RNA (gRNA) to cleave target DNA or RNA. The discovery of collateral cleavage in CRISPR-Cas effectors such as Cas12a and Cas13a was intensively repurposed for the development of instrument-free, sensitive, precise and rapid point-of-care diagnostics. CRISPR/Cas demonstrated proficiency in detecting non-nucleic acid targets including protein, analyte, and hormones other than nucleic acid. CRISPR/Cas effectors can provide multiple detections simultaneously. The present review highlights the technical challenges of integrating CRISPR/Cas technology into the onsite assessment of clinical and other specimens, along with current improvements in CRISPR bio-sensing for nucleic acid and non-nucleic acid targets. It also highlights the current applications of CRISPR/Cas technologies.


Assuntos
Sistemas CRISPR-Cas , Ácidos Nucleicos , Sistemas CRISPR-Cas/genética , DNA , Ácidos Nucleicos/genética , RNA , RNA Guia de Sistemas CRISPR-Cas
4.
Indian J Microbiol ; 60(3): 388-391, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32647398

RESUMO

Pesticide accumulation in agricultural soils is an environmental concern, often addressed through distinct bioremediation strategies. This study has tried to analyze various soil bioremediation options viz., biostimulation, bioaugmentation, and natural attenuation in terms of efficiency and the response of autochthonous microbial flora by using atrazine as a model contaminant. Soil mesocosms were established with 100 kg of soil simulating the field conditions. The soil previously exposed to the herbicide was used for the bioaugmentation strategy undertaken in this study. We have tried to analyze how the microbial community responds to a foreign compound, both in terms of taxonomic and functional capacities? To answer this, we have analyzed metagenome of the mesocosms at a time point when 90% atrazine was degraded. Bioaugmentation for bioremediation proved to be efficient with a DT90 value of 15.48 ± 0.79 days, in comparison to the natural attenuation where the DT90 value was observed to be 41.20 ± 1.95 days. Metagenomic analysis revealed the abundance of orders Erysipelotrichales, Selemonadales, Clostridiales, and Thermoanaerobacterales exclusively in SBS mesocosm. Besides Pseudomonas, bacterial genera such as Achromobacter, Xanthomonas, Stenotrophomonas, and Cupriavidus have emerged as the dominant members in various bioremediation strategies tested in this study. Inclusive results suggest that inherent microbial flora adjust their community and metabolic machinery upon exposure to the pollutant. The site under pollutant stress showed efficient microbial communities to bio-remediate the newly polluted terrestrial ecologies in relatively less time and by economic means.

5.
Artigo em Inglês | MEDLINE | ID: mdl-29038276

RESUMO

Vancomycin-resistant Enterococcus faecium strains (VREfm) are critical public health concerns because they are among the leading causes of hospital-acquired bloodstream infections. Chlorhexidine (CHX) is a bisbiguanide cationic antiseptic that is routinely used for patient bathing and other infection control practices. VREfm are likely frequently exposed to CHX; however, the long-term effects of CHX exposure have not been studied in enterococci. In this study, we serially exposed VREfm to increasing concentrations of CHX for a period of 21 days in two independent experimental evolution trials. Reduced CHX susceptibility emerged (4-fold shift in CHX MIC). Subpopulations with reduced daptomycin (DAP) susceptibility were detected, which were further analyzed by genome sequencing and lipidomic analysis. Across the trials, we identified adaptive changes in genes with predicted or experimentally confirmed roles in chlorhexidine susceptibility (efrE), global nutritional stress response (relA), nucleotide metabolism (cmk), phosphate acquisition (phoU), and glycolipid biosynthesis (bgsB), among others. Moreover, significant alterations in membrane phospholipids were identified for some populations with reduced DAP susceptibility. Our results are clinically significant because they identify a link between serial subinhibitory CHX exposure and reduced DAP susceptibility. In addition, the CHX-induced genetic and lipidomic changes described in this study offer new insights into the mechanisms underlying the emergence of antibiotic resistance in VREfm.


Assuntos
Antibacterianos/farmacologia , Clorexidina/farmacologia , Daptomicina/farmacologia , Enterococos Resistentes à Vancomicina/efeitos dos fármacos , Enterococos Resistentes à Vancomicina/genética , Anti-Infecciosos Locais/farmacologia , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Ligases/genética , Testes de Sensibilidade Microbiana , Mutação , Fosfolipídeos/genética , Fosfolipídeos/metabolismo
6.
Antimicrob Agents Chemother ; 60(4): 2209-21, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26810654

RESUMO

Chlorhexidine is a bisbiguanide antiseptic used for infection control. Vancomycin-resistantE. faecium(VREfm) is among the leading causes of hospital-acquired infections. VREfm may be exposed to chlorhexidine at supra- and subinhibitory concentrations as a result of chlorhexidine bathing and chlorhexidine-impregnated central venous catheter use. We used RNA sequencing to investigate how VREfm responds to chlorhexidine gluconate exposure. Among the 35 genes upregulated ≥10-fold after 15 min of exposure to the MIC of chlorhexidine gluconate were those encoding VanA-type vancomycin resistance (vanHAX) and those associated with reduced daptomycin susceptibility (liaXYZ). We confirmed thatvanAupregulation was not strain or species specific by querying other VanA-type VRE. VanB-type genes were not induced. ThevanHpromoter was found to be responsive to subinhibitory chlorhexidine gluconate in VREfm, as was production of the VanX protein. UsingvanHreporter experiments withBacillus subtilisand deletion analysis in VREfm, we found that this phenomenon is VanR dependent. Deletion ofvanRdid not result in increased chlorhexidine susceptibility, demonstrating thatvanHAXinduction is not protective against chlorhexidine. As expected, VanA-type VRE is more susceptible to ceftriaxone in the presence of sub-MIC chlorhexidine. Unexpectedly, VREfm is also more susceptible to vancomycin in the presence of subinhibitory chlorhexidine, suggesting that chlorhexidine-induced gene expression changes lead to additional alterations in cell wall synthesis. We conclude that chlorhexidine induces expression of VanA-type vancomycin resistance genes and genes associated with daptomycin nonsusceptibility. Overall, our results indicate that the impacts of subinhibitory chlorhexidine exposure on hospital-associated pathogens should be further investigated in laboratory studies.


Assuntos
Anti-Infecciosos Locais/farmacologia , Proteínas de Bactérias/agonistas , Clorexidina/análogos & derivados , Enterococcus faecium/efeitos dos fármacos , Regulação Bacteriana da Expressão Gênica , Resistência a Vancomicina/efeitos dos fármacos , Antibacterianos/farmacologia , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Carbono-Oxigênio Ligases/genética , Carbono-Oxigênio Ligases/metabolismo , Parede Celular/efeitos dos fármacos , Parede Celular/metabolismo , Clorexidina/farmacologia , Daptomicina/farmacologia , Enterococcus faecium/genética , Enterococcus faecium/crescimento & desenvolvimento , Enterococcus faecium/metabolismo , Perfilação da Expressão Gênica , Testes de Sensibilidade Microbiana , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Vancomicina/farmacologia , Resistência a Vancomicina/genética
7.
Appl Microbiol Biotechnol ; 100(2): 903-13, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26403923

RESUMO

The Arthrobacter sp. strain AK-YN10 is an s-triazine pesticide degrading bacterium isolated from a sugarcane field in Central India with history of repeated atrazine use. AK-YN10 was shown to degrade 99 % of atrazine in 30 h from media supplemented with 1000 mg L(-1) of the herbicide. Draft genome sequencing revealed similarity to pAO1, TC1, and TC2 catabolic plasmids of the Arthrobacter taxon. Plasmid profiling analyses revealed the presence of four catabolic plasmids. The trzN, atzB, and atzC atrazine-degrading genes were located on a plasmid of approximately 113 kb.The flagellar operon found in the AK-YN10 draft genome suggests motility, an interesting trait for a bioremediation agent, and was homologous to that of Arthrobacter chlorophenolicus. The multiple s-triazines degradation property of this isolate makes it a good candidate for bioremediation of soils contaminated by s-triazine pesticides.


Assuntos
Arthrobacter/genética , Arthrobacter/metabolismo , Atrazina/metabolismo , Biodegradação Ambiental , Herbicidas/metabolismo , Microbiologia do Solo , Arthrobacter/efeitos dos fármacos , Arthrobacter/isolamento & purificação , Atrazina/farmacologia , Sequência de Bases , Genoma Bacteriano , Índia , Plasmídeos , Reação em Cadeia da Polimerase , Saccharum/microbiologia
8.
Cureus ; 16(5): e61430, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38947601

RESUMO

This case report describes the care given to a 58-year-old male patient with severe upper jaw atrophy. The treatment strategy involved utilizing zygomatic implants in conjunction with endosteal implants to rehabilitate both the maxilla and mandible. Temporary prostheses were used during the healing phase, followed by the fabrication and placement of final prostheses. The utilization of zygomatic implants offers advantages such as immediate stabilization and function without the need for extensive bone grafting. This approach not only reduces treatment time and costs but also enhances patient outcomes. Furthermore, guided surgical techniques are increasingly employed to ensure precise implant placement, optimizing prosthetic support.

9.
Mol Biotechnol ; 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38366109

RESUMO

Calanthe mild mosaic virus (CalMMV) infecting orchids is an important potyvirus which is known to cause mild leaf mosaic and flower colour-breaking symptoms in Calanthe and other orchid plants. The present study reports the production of polyclonal antibodies against CalMMV using bacterially expressed recombinant coat protein as immunogen, which in turn would be useful in routine indexing and screening of orchid germplasm. The coat protein (CP) gene (~ 807 bp) of CalMMV isolated from infected orchid sample was cloned in expression vector, pET-28a ( +) that yielded ~ 31 kDa fusion protein with Histidine tag (His6BP). The expression of fusion CP was confirmed through SDS-PAGE and Western blotting. The His6BP-CalMMV-CP obtained in soluble state after purification was used to immunize New Zealand white rabbit for the production of polyclonal antibodies (PAb). The PAb produced against the purified fusion protein successfully detected CAlMMV in the orchid samples at a dilution of 1:2000 in direct antigen-coated enzyme-linked immunosorbent assay (DAC-ELISA). This study presents the first report of Histidine tag (His6BP) fusion CalMMV-CP-based antibody production and its successful application in the identification of the virus in orchid plants. Outcome of this study will be helpful in routine certification programmes, screening of orchid germplasm and production of CalMMV-free planting materials of orchids.

10.
Indian J Anaesth ; 68(2): 189-195, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38435662

RESUMO

Background and Aims: Adequate sedation is essential for children undergoing magnetic resonance imaging (MRI) console. Propofol is commonly used for sedation, but it has the drawback of upper airway collapse at higher doses, which may be overcome by ketamine. This study was designed to evaluate the beneficial effect of ketamine on propofol in preventing airway collapse. Methods: Fifty-eight children undergoing MRI were randomised to Group P (propofol bolus dose followed by infusion or Group KP (bolus dose of ketamine and propofol followed by propofol infusion). The primary aim is to compare the upper airway cross-sectional area (CSA) and diameters (transverse diameter [TD] and anteroposterior diameter [APD]) obtained from MRI during inspiration and expiration. Results: Upper airway collapse as measured by delta CSA in mean (SD) [95% confidence interval] was statistically more significant between the two groups [at the soft palate level, 16.9 mm2 (19.8) [9.3-24.4] versus 9.0 mm2 (5.50) [6.9-11.1] (P = 0.043); at the base of the tongue level, 15.4 mm2 (11.03) [11.2-19.6] versus 7.48 mm2 (4.83) [5.64-9.32] (P < 0.001); at the epiglottis level, 23.9 (26.05) [14.0-33.8] versus 10.9 mm2 (9.47) [7.35-14.5] (P = 0.014)]. A significant difference was obtained for TD at all levels and for APD at the soft palate and base of tongue level. Conclusion: Adding a single dose of ketamine to propofol reduced the upper airway collapse significantly, as evidenced by the MRI-based measurements of upper airway dimensions, compared to propofol alone.

11.
Infect Dis Now ; 54(2): 104865, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38350558

RESUMO

OBJECTIVES: To identify the potential target genes for detection of Orientia tsutsugamushi (OT) in pediatric acute encephalitis syndrome (pAES). METHODS: DNA was extracted from whole blood of 100 pAES cases having tested positive (n = 41) and negative (n = 59) for scrub typhus (ST) by IgM ELISA. These samples were subjected to standard PCR for 56 kDa, 47 kDa, 16 s rRNA, groEL, traD genes and the newly identified 27 kDa gene. RESULTS: Among the selected gene targets, 56 kDa demonstrated its superiority for OT detection over the other tested genes. The presence of OT was confirmed via PCR targeting 56 kDa gene in 17 out of the 41 (41.4 %) IgM-positive ST AES cases and 38 out of the 59 (64.4 %) ST IgM negative cases. None of the other gene targets were amplified. CONCLUSION: Integration of serological diagnosis with molecular diagnostics targeting the 56 kDa gene for routine testing of AES patients would facilitate detection of OT in AES endemic regions.


Assuntos
Encefalopatia Aguda Febril , Tifo por Ácaros , Criança , Humanos , Tifo por Ácaros/diagnóstico , Encefalopatia Aguda Febril/diagnóstico , Ensaio de Imunoadsorção Enzimática , Imunoglobulina M , Reação em Cadeia da Polimerase
12.
EXCLI J ; 22: 451-465, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37534220

RESUMO

SARS-CoV-2 has mutated rapidly since its first case report in Wuhan, China, leading to the emergence of an indefinite number of variants. India has witnessed three waves of the COVID-19 pandemic. The country saw its first wave of SARS-CoV-2 illness from late January 2020 to February 2021. With a peak surge of cases in mid-September 2020, India recorded more than 11 million cases and a death toll of more than 0.165 million at this time. India faced a brutal second wave driven by the emergence of highly infectious SARS-CoV-2 variants B.1.617.2 (Delta variant) and the third wave with the leading cause of BA.2 (Omicron variant), which has led to an unprecedented rise in COVID-19 cases in the country. On September 14, 2022, India recorded a cumulative 44.51 million cases of COVID-19 with more than 0.528 million deaths. The discovery of common circulating mutants is facilitated by genome sequencing. The changes in the Spike surface glycoprotein recombinant binding domains served as the critical alterations, resulting in enhanced infectivity and transmissibility, with severe clinical effects. Further, the predominant mutation in the SARS-CoV-2 spike protein; the D614G strains served as a model for vaccine development. The mutation of the Wuhan strain to the Variant of Concern led to a significant increase in SARS-CoV-2 infections. In addition, there was a shift in the age group affected by SARS-CoV-2 variant infection. The current review summarized the COVID-19 pandemic's Variant of Concern and the advent of SARS-CoV-2 in India.

13.
Virology ; 587: 109872, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37657354

RESUMO

Reverse-transcription loop-mediated isothermal amplification (RT-LAMP) assay was developed for detection of groundnut bud necrosis virus (GBNV) causing potato stem necrosis disease. The isothermal temperatures, reaction periods and concentrations of reaction mixture were optimized where, the assay worked well at 65 °C for 50 min, 6 U of WarmStart Bst 2.0 DNA polymerase, 1.4 mM dNTPs and 2.0 mM MgSO4. The optimized assay proved to be specific to GBNV with no cross reactivity to other viruses infecting potato in India. The specificity of RT-LAMP assay was found to be 100 fold more sensitive than that of RT-PCR. The developed assay was applied for the detection of GBNV from 80 potato leaf samples where 24 samples were found infected which was confirmed by RT-PCR. It was concluded that the RT-LAMP assay developed for detection of GBNV was specific, sensitive and suitable for its use in virus indexing under potato seed production programme.


Assuntos
Solanum tuberosum , Vírus , Transcrição Reversa , Técnicas de Amplificação de Ácido Nucleico , Sensibilidade e Especificidade
14.
PeerJ ; 11: e14504, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36643644

RESUMO

Dengue fever is an endemic disease in India, transmitted by an infected mosquito bite. In India, the number of concurrent infections and the circulation of multiple dengue virus (DENV) serotypes has increased in recent decades. Molecular surveillance among the DENV serotype is important to keep track of the circulating serotypes, evolutionary changes, and key mutations that can alter the diagnostics. The current study included patients admitted for dengue in the Eastern Uttar Pradesh (E-UP) region during 2018-2019. The genetic characterization of the circulating DENV was accomplished through partial CprM (511 bp) gene amplification via reverse transcriptase polymerase chain reaction and sequencing. Phylogenetic analysis revealed the circulation of all four DENV1-4 serotypes. DENV-2 was the most abundant serotype (44%, 27/61), followed by DENV-3 (32%, 20/61). DENV-1 had a 16% (10/61) predominance, while DENV-4 (6%, 4/61) was found to be the least abundant serotype. DENV-2 genotypes were distributed among lineages I (7.4%), II (85%) and III (7.4%) of genotype IV, DENV-3 to lineage III of genotype III, DENV-1 to genotype III; DENV-2 to lineage B (75%) and C (25%) of genotype I. This primary report on the co-circulation of DENV1-4 serotypes from the E-UP region highlights the requirement of continuous molecular surveillance for monitoring circulating DENV serotypes.


Assuntos
Vírus da Dengue , Dengue , Humanos , Vírus da Dengue/genética , Dengue/epidemiologia , Sorogrupo , Filogenia , Índia/epidemiologia
15.
Biosensors (Basel) ; 13(12)2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38131781

RESUMO

Orientia tsutsugamushi is responsible for causing scrub typhus (ST) and is the leading cause of acute encephalitis syndrome (AES) in AES patients. A rapid and sensitive method to detect scrub typhus on-site is essential for the timely deployment of control measures. In the current study, we developed a rapid, sensitive, and instrument-free lateral flow assay (LFA) detection method based on CRISPR/Cas12a technology for diagnosing ST (named LoCIST). The method is completed in three steps: first, harnessing the ability of recombinase polymerase for isothermal amplification of the target gene; second, CRISPR/Cas12a-based recognition of the target; and third, end-point detection by LFA. The detection limit of LoCIST was found to be one gene copy of ST genomic DNA per reaction, and the process was complete within an hour. In 81 clinical samples, the assay showed no cross-reactivity with other rickettsial DNA and was 100% consistent with PCR detection of ST. LoCIST demonstrated 97.6% sensitivity and 100% specificity. Overall, the LoCIST offers a novel alternative for the portable, simple, sensitive, and specific detection of ST, and it may help prevent and control AES outbreaks due to ST. In conclusion, LoCIST does not require specialized equipment and poses a potential for future applications as a point-of-care diagnostic.


Assuntos
Orientia tsutsugamushi , Tifo por Ácaros , Humanos , Tifo por Ácaros/diagnóstico , Tifo por Ácaros/genética , Sistemas CRISPR-Cas , Sensibilidade e Especificidade , Orientia tsutsugamushi/genética , DNA
16.
Zoonoses Public Health ; 70(5): 403-410, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37086017

RESUMO

The Eastern Uttar Pradesh region of India is known for its endemicity of acute encephalitis syndrome (AES). Decades of research have established that Orientia tsutsugamushi, a causative of scrub typhus, is a substantial contributor (>60%) for the AES cases besides other aetiology, but additional factors in the remaining proportion are still unidentified. Rickettsial infections are challenging to diagnose in clinical settings due to overlapping clinical symptoms, the absence of definitive indicators, a low index of suspicion, and the lack of low-cost, rapid diagnostic tools. Hence, the present study was designed to determine the load of rickettsial infections among AES cases. Furthermore, we aim to find out the prevalent rickettsial species in AES cases as well as in the vector population at this location. The study included the whole blood/cerebrospinal fluid of AES patients and arthropod specimens from rodents. The molecular identification was performed using the 23S-5S intergenic spacer region and ompB gene with genomic DNA obtained from studied specimens. We detected 5.34% (62/1160) of rickettsial infection in AES cases. Among these, phylogenetic analysis confirmed the presence of 54.8% Rickettsia conorii (n = 34) and 16.1% of Rickettsia felis (n = 10), while the rest proportion of the isolates was unidentified at the species level. Furthermore, R. felis was identified in one CSF sample from AES patients and three flea samples from Xenopsylla cheopis. Rickettsia spp. was also confirmed in one Ornithonyssus bacoti mite sample. The results of this investigation concluded the presence of spotted fever group Rickettsia spp. among AES identified cases as well as in the mite and flea vectors that infest rodents.


Assuntos
Encefalopatia Aguda Febril , Infecções por Rickettsia , Rickettsia , Tifo por Ácaros , Rickettsiose do Grupo da Febre Maculosa , Animais , Encefalopatia Aguda Febril/epidemiologia , Encefalopatia Aguda Febril/etiologia , Encefalopatia Aguda Febril/veterinária , Filogenia , Tifo por Ácaros/epidemiologia , Tifo por Ácaros/veterinária , Infecções por Rickettsia/epidemiologia , Infecções por Rickettsia/veterinária , Roedores , Rickettsiose do Grupo da Febre Maculosa/epidemiologia , Rickettsiose do Grupo da Febre Maculosa/veterinária , Índia/epidemiologia
17.
PLoS One ; 16(4): e0249631, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33831063

RESUMO

Vancomycin-resistant enterococci (VRE) are important nosocomial pathogens that cause life-threatening infections. To control hospital-associated infections, skin antisepsis and bathing utilizing chlorhexidine is recommended for VRE patients in acute care hospitals. Previously, we reported that exposure to inhibitory chlorhexidine levels induced the expression of vancomycin resistance genes in VanA-type Enterococcus faecium. However, vancomycin susceptibility actually increased for VanA-type E. faecium in the presence of chlorhexidine. Hence, a synergistic effect of the two antimicrobials was observed. In this study, we used multiple approaches to investigate the mechanism of synergism between chlorhexidine and vancomycin in the VanA-type VRE strain E. faecium 1,231,410. We generated clean deletions of 7 of 11 pbp, transpeptidase, and carboxypeptidase genes in this strain (ponA, pbpF, pbpZ, pbpA, ddcP, ldtfm, and vanY). Deletion of ddcP, encoding a membrane-bound carboxypeptidase, altered the synergism phenotype. Furthermore, using in vitro evolution, we isolated a spontaneous synergy escaper mutant and utilized whole genome sequencing to determine that a mutation in pstB, encoding an ATPase of phosphate-specific transporters, also altered synergism. Finally, addition of excess D-lactate, but not D-alanine, enhanced synergism to reduce vancomycin MIC levels. Overall, our work identified factors that alter chlorhexidine and vancomycin synergism in a model VanA-type VRE strain.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Adenosina Trifosfatases/metabolismo , Proteínas de Bactérias/metabolismo , Clorexidina/farmacologia , Sinergismo Farmacológico , Enterococcus faecium/efeitos dos fármacos , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Ácido Láctico/metabolismo , Vancomicina/farmacologia , Transportadores de Cassetes de Ligação de ATP/genética , Adenosina Trifosfatases/genética , Antibacterianos/farmacologia , Anti-Infecciosos Locais/farmacologia , Proteínas de Bactérias/genética , Infecções por Bactérias Gram-Positivas/genética , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos
18.
Access Microbiol ; 3(3): 000214, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34151166

RESUMO

Enterococcus faecalis and E. faecium are Gram-positive bacteria that normally inhabit the human gastrointestinal tract. They are also opportunistic pathogens and can cause nosocomial infection outbreaks. To prevent the spread of nosocomial infections, hospitals may rely on screening methods to identify patients colonized with multidrug-resistant organisms including vancomycin-resistant enterococci (VRE). Spectra VRE agar (Remel) contains vancomycin and other medium components that select for VRE and phenotypically differentiate between E. faecalis and E. faecium by colony colour. We obtained 66 de-identified rectal swab cultures on Spectra VRE agar that were obtained during routine patient admission surveillance at a hospital system in Dallas, Texas, USA. We analysed 90 presumptive VRE from 61 of the Spectra VRE agar cultures using molecular and culture methods. Using ddl typing, 55 were found to be E. faecium and 32 were found to be E. faecalis . While most of the E. faecium were positive for the vanA gene by PCR (52 of 55 strains), few of the E. faecalis were positive for either vanA or vanB (five of 32 strains). The 27 E. faecalis vanA- and vanB-negative strains could not be recultured on Spectra VRE agar. Overall, we found that Spectra VRE agar performed robustly for the identification of vancomycin-resistant E. faecium , but presumptive false positives were obtained for vancomycin-resistant E. faecalis .

19.
Curr Drug Deliv ; 18(4): 500-512, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32723271

RESUMO

OBJECTIVE: The objective of the current research work was to prepare chewable tablets having Acacia catechu extract useful for mouth ulcers using a 32 factorial design. METHODS: Acacia catechu heartwood extract was prepared using a reported method with some modifications. The extract was characterized using TLC against the catechin marker. Then, drug-excipient interaction studies were carried out. The mixture of drug and excipients was evaluated for pre-compression parameters. With the application of 32 factorial design, chewable tablets were prepared using direct compression technique. Prepared tablets were evaluated for post-compression parameters. RESULTS: In vitro drug release study of the developed formulations was investigated both in intact and crushed form of tablets. Based on the in vitro performance, the best formulations were selected (F6, F7 & F8 from intact and F1, F5 & F9 from the crushed group) and subjected to various kinetic models and evaluated for Chewing Difficulty Index (CDI). CONCLUSION: The overall results revealed that the formulated chewable tablets complied with the standards and exhibited the satisfactory performance in terms of drug release, chewing difficulty index and other related parameters.


Assuntos
Acacia , Úlceras Orais , Extratos Vegetais/administração & dosagem , Comprimidos , Acacia/química , Administração Oral , Excipientes , Úlceras Orais/tratamento farmacológico
20.
Front Med (Lausanne) ; 8: 781287, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35071267

RESUMO

Uttar Pradesh is the densely populated state of India and is the sixth highest COVID-19 affected state with 22,904 deaths recorded on November 12, 2021. Whole-genome sequencing (WGS) is being used as a potential approach to investigate genomic evolution of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus. In this study, a total of 87 SARS-CoV-2 genomes-49 genomes from the first wave (March 2020 to February 2021) and 38 genomes from the second wave (March 2021 to July 2021) from Eastern Uttar Pradesh (E-UP) were sequenced and analyzed to understand its evolutionary pattern and variants against publicaly available sequences. The complete genome analysis of SARS-CoV-2 during the first wave in E-UP largely reported transmission of G, GR, and GH clades with specific mutations. In contrast, variants of concerns (VOCs) such as Delta (71.0%) followed by Delta AY.1 (21.05%) and Kappa (7.9%) lineages belong to G clade with prominent signature amino acids were introduced in the second wave. Signature substitution at positions S:L452R, S:P681R, and S:D614G were commonly detected in the Delta, Delta AY.1, and Kappa variants whereas S:T19R and S:T478K were confined to Delta and Delta AY.1 variants only. Vaccine breakthrough infections showed unique mutational changes at position S:D574Y in the case of the Delta variant, whereas position S:T95 was conserved among Kappa variants compared to the Wuhan isolate. During the transition from the first to second waves, a shift in the predominant clade from GH to G clade was observed. The identified spike protein mutations in the SARS-CoV-2 genome could be used as the potential target for vaccine and drug development to combat the effects of the COVID-19 disease.

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