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1.
Int J Low Extrem Wounds ; : 15347346231226342, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38233034

RESUMO

BACKGROUND: Chronic wounds are prevalent globally at endemic proportions. The common features associated with chronic wounds are prolonged inflammatory phase, infection with multidrug-resistant (MDR) bacteria, and subsequent biofilm formation. The present randomized-controlled trial (RCT) study was undertaken on chronic wounds of ≥6 weeks longer duration using customized phages to evaluate the efficacy and safety of bacteriophage therapy. METHODS: The study was conducted from December 2021 to August 2023. Thirty patients in each of the arms (placebo and bacteriophage) were recruited with chronic wounds. The patients, both arms, received the conventional treatment of wound debridement, local antiseptics, and local and systemic antibiotics at the discretion of the treating surgeon. However, before applying the customized bacteriophage cocktail or placebo, the wound surface was thoroughly washed to remove the residual antiseptics. The phage cocktails or placebo were applied on alternate days. The wounds were evaluated using the Bates-Jensen Wound Assessment Tool for the progress of wound healing. RESULTS: A total of 93.3% of the wound became sterile in 39 days (median sterility time), followed by complete healing by the end of 90 days in the phage group. Contrary to this, 83.3% of those on placebo therapy remained colonized by original bacteria or additional new bacteria without healing for up to 90 days. CONCLUSION: With the well-designed RCT, we could conclude that customized bacteriophage therapy using bacteriophage cocktails will definitely cure the chronic wound, irrespective of age, sex, diabetes status, and infection by MDR bacteria.

2.
Front Med (Lausanne) ; 10: 1209782, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37928478

RESUMO

The recent approval of experimental phage therapies by the FDA and other regulatory bodies with expanded access in cases in the United States and other nations caught the attention of the media and the general public, generating enthusiasm for phage therapy. It started to alter the situation so that more medical professionals are willing to use phage therapies with conventional antibiotics. However, more study is required to fully comprehend phage therapy's potential advantages and restrictions, which is still a relatively new field in medicine. It shows promise, nevertheless, as a secure and prosperous substitute for antibiotics when treating bacterial illnesses in animals and humans. Because of their uniqueness, phage disinfection is excellent for ready-to-eat (RTE) foods like milk, vegetables, and meat products. The traditional farm-to-fork method can be used throughout the food chain to employ bacteriophages to prevent food infections at all production stages. Phage therapy improves clinical outcomes in animal models and lowers bacterial burdens in numerous preclinical investigations. The potential of phage resistance and the need to make sure that enough phages are delivered to the infection site are obstacles to employing phages in vivo. However, according to preclinical studies, phages appear to be a promising alternative to antibiotics for treating bacterial infections in vivo. Phage therapy used with compassion (a profound understanding of and empathy for another's suffering) has recently grown with many case reports of supposedly treated patients and clinical trials. This review summarizes the knowledge on the uses of phages in various fields, such as the food industry, preclinical research, and clinical settings. It also includes a list of FDA-approved bacteriophage-based products, commercial phage products, and a global list of companies that use phages for therapeutic purposes.

3.
mBio ; : e0147623, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37931127

RESUMO

Changing climatic conditions influence parameters associated with the growth of pathogenic Vibrio spp. in the environment and, hence, are linked to increased incidence of vibriosis. Between 1992 and 2022, a long-term increase in Vibrio spp. infections was reported in Florida, USA. Furthermore, a spike in Vibrio spp. infections was reported post Hurricane Ian, a category five storm that made landfall in Florida on 28 September 2022. During October 2022, water and oyster samples were collected from three stations in Lee County in an area significantly impacted by Ian. Vibrio spp. were isolated, and whole-genome sequencing and phylogenetic analysis were done, with a focus on Vibrio parahaemolyticus and Vibrio vulnificus to provide genetic insight into pathogenic strains circulating in the environment. Metagenomic analysis of water samples provided insight with respect to human health-related factors, notably the detection of approximately 12 pathogenic Vibrio spp., virulence and antibiotic resistance genes, and mobile genetic elements, including the SXT/R391 family of integrative conjugative elements. Environmental parameters were monitored as part of a long-term time series analysis done using satellite remote sensing. In addition to anomalous rainfall and storm surge, changes in sea surface temperature and chlorophyll concentration during and after Ian favored the growth of Vibrio spp. In conclusion, genetic analysis coupled with environmental data and remote sensing provides useful public health information and, hence, constitute a valuable tool to proactively detect and characterize environmental pathogens, notably vibrios. These data can aid the development of early warning systems by yielding a larger source of information for public health during climate change. Evidence suggests warming temperatures are associated with the spread of potentially pathogenic Vibrio spp. and the emergence of human disease globally. Following Hurricane Ian, the State of Florida reported a sharp increase in the number of reported Vibrio spp. infections and deaths. Hence, monitoring of pathogens, including vibrios, and environmental parameters influencing their occurrence is critical to public health. Here, DNA sequencing was used to investigate the genomic diversity of Vibrio parahaemolyticus and Vibrio vulnificus, both potential human pathogens, in Florida coastal waters post Hurricane Ian, in October 2022. Additionally, the microbial community of water samples was profiled to detect the presence of Vibrio spp. and other microorganisms (bacteria, fungi, protists, and viruses) present in the samples. Long-term environmental data analysis showed changes in environmental parameters during and after Ian were optimal for the growth of Vibrio spp. and related pathogens. Collectively, results will be used to develop predictive risk models during climate change.

4.
bioRxiv ; 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37808627

RESUMO

Members of the genus Vibrio are ecologically significant bacteria native to aquatic ecosystems globally, and a few can cause diseases in humans. Vibrio-related illnesses have increased in recent years, primarily attributed to changing environmental conditions. Therefore, understanding the role of environmental factors in the occurrence and growth of pathogenic strains is crucial for public health. Water, oyster, and sediment samples were collected between 2009 and 2012 from Chester River and Tangier Sound sites in Chesapeake Bay, Maryland, USA, to investigate the relationship between water temperature, salinity, and chlorophyll with the incidence and distribution of Vibrio parahaemolyticus (VP) and Vibrio vulnificus (VV). Odds ratio analysis was used to determine association between the likelihood of VP and VV presence and these environmental variables. Results suggested that water temperature threshold of 20°C or higher was associated with an increased risk, favoring the incidence of Vibrio spp. A significant difference in salinity was observed between the two sampling sites, with distinct ranges showing high odds ratio for Vibrio incidence, especially in water and sediment, emphasizing the impact of salinity on VP and VV incidence and distribution. Notably, salinity between 9-20 PPT consistently favored the Vibrio incidence across all samples. Relationship between chlorophyll concentrations and VP and VV incidence varied depending on sample type. However, chlorophyll range of 0-10 µg/L was identified as critical in oyster samples for both vibrios. Analysis of odds ratios for water samples demonstrated consistent outcomes across all environmental parameters, indicating water samples offer a more reliable indicator of Vibrio spp. incidence.

5.
Pharmaceuticals (Basel) ; 16(7)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37513854

RESUMO

Multidrug-resistant (MDR) Acinetobacter baumannii (A. baumannii) is one of the major pathogens present in burn wound infections. Biofilm formation makes it further challenging to treat with clinically available antibiotics. In the current work, we isolated the A. baumannii-specific bacteriophages (BPABΦ1), loaded into the chitosan microparticles followed by dispersion in gel, and evaluated therapeutic efficacy against MDR A. baumannii clinical strains. Isolated BPABΦ1 were found to belong to the Corticoviridae family, with burst size 102.12 ± 2.65 PFUs per infected host cell. The BPABΦ1 loaded chitosan microparticles were evaluated for quality attributes viz. size, PDI, surface morphology, in vitro release, etc. The developed formulation exhibited excellent antibiofilm eradication potential in vitro and effective wound healing after topical application.

6.
Spectrochim Acta A Mol Biomol Spectrosc ; 302: 123045, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37356391

RESUMO

To control the spread of the disease, the Zika virus (ZIKV), a flavivirus infection spread by mosquitoes and common in across the world, needs to be accurately and promptly diagnosed. This endeavour gets challenging when early-stage illnesses have low viral loads. As a result, we have created a biosensor based on surface-enhanced Raman scattering (SERS) for the quick, accurate, and timely diagnosis of the Zika virus. In this study, a glass coverslip was coated with silver nanoislands, which were then utilized as the surface for creating the sensing platform. Silver nanoislands exhibit strong plasmonic activity and good conductive characteristics. It enhances the Raman signals as a result and gives the SERS platform an appropriate surface. The created platform has been applied to Zika virus detection. With a limit of detection (LOD) of 0.11 ng/mL, the constructed sensor exhibits a linear range from 5 ng/mL to 1000 ng/mL. Hence, even at the nanogram scale, this technique may be a major improvement over clinical diagnosis approaches for making proper, precise, and accurate Zika virus detection.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Infecção por Zika virus , Zika virus , Animais , Humanos , Infecção por Zika virus/diagnóstico , Prata , Técnicas Biossensoriais/métodos , Análise Espectral Raman/métodos
7.
Appl Environ Microbiol ; 89(6): e0030723, 2023 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-37222620

RESUMO

Incidence of vibriosis is rising globally, with evidence that changing climatic conditions are influencing environmental factors that enhance growth of pathogenic Vibrio spp. in aquatic ecosystems. To determine the impact of environmental factors on occurrence of pathogenic Vibrio spp., samples were collected in the Chesapeake Bay, Maryland, during 2009 to 2012 and 2019 to 2022. Genetic markers for Vibrio vulnificus (vvhA) and Vibrio parahaemolyticus (tlh, tdh, and trh) were enumerated by direct plating and DNA colony hybridization. Results confirmed seasonality and environmental parameters as predictors. Water temperature showed a linear correlation with vvhA and tlh, and two critical thresholds were observed, an initial increase in detectable numbers (>15°C) and a second increase when maximum counts were recorded (>25°C). Temperature and pathogenic V. parahaemolyticus (tdh and trh) were not strongly correlated; however, the evidence showed that these organisms persist in oyster and sediment at colder temperatures. Salinity (10 to 15 ppt), total chlorophyll a (5 to 25 µg/L), dissolved oxygen (5 to 10 mg/L), and pH (8) were associated with increased abundance of vvhA and tlh. Importantly, a long-term increase in Vibrio spp. numbers was observed in water samples between the two collection periods, specifically at Tangier Sound (lower bay), with the evidence suggesting an extended seasonality for these bacteria in the area. Notably, tlh showed a mean positive increase that was ca. 3-fold overall, with the most significant increase observed during the fall. In conclusion, vibriosis continues to be a risk in the Chesapeake Bay region. A predictive intelligence system to assist decision makers, with respect to climate and human health, is warranted. IMPORTANCE The genus Vibrio includes pathogenic species that are naturally occurring in marine and estuarine environments globally. Routine monitoring for Vibrio species and environmental parameters influencing their incidence is critical to provide a warning system for the public when the risk of infection is high. In this study, occurrence of Vibrio parahaemolyticus and Vibrio vulnificus, both potential human pathogens, in Chesapeake Bay water, oysters, and sediment samples collected over a 13-year period was analyzed. The results provide a confirmation of environmental predictors for these bacteria, notably temperature, salinity, and total chlorophyll a, and their seasonality of occurrence. New findings refine environmental parameter thresholds of culturable Vibrio species and document a long-term increase in Vibrio populations in the Chesapeake Bay. This study provides a valuable foundation for development of predicative risk intelligence models for Vibrio incidence during climate change.


Assuntos
Ostreidae , Vibrioses , Vibrio parahaemolyticus , Vibrio vulnificus , Animais , Humanos , Vibrio parahaemolyticus/genética , Vibrio vulnificus/genética , Clorofila A , Ecossistema , Ostreidae/microbiologia , Vibrioses/epidemiologia , Água
8.
Cannabis Cannabinoid Res ; 8(6): 1019-1029, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-35443806

RESUMO

Introduction: The study was planned to investigate memory-enhancing, anti-inflammatory, and antiaging potential of cannabidiol (CBD) on vitamin D3 deficient diet (VDD)-induced rats. Materials and Methods: Cytochrome P-450 enzymes were analyzed by RT-PCR method and others biomarkers by enzyme-linked immunosorbent assay. Results: CYP2R1 and CYP27B1-mRNA were significantly increased by 39.29 and 38.37%, respectively, while; CYP24A1-mRNA was significantly reduced by 21.39% compared to VDD. Vitamin D3 receptor protein expression was significantly increased by 148.3%, 60.48%, and 142.03% in liver, kidney, and brain, respectively, compared to VDD group. Vitamin D3 metabolites and serotonin were significantly increased more than 60% and 100%, respectively, compared to VDD. Spatial memory (in terms of total distance, escape latency) and pain score were improved compared to VDD. Cytokines were significantly reduced than VDD. Besides, levels of superoxide dismutase (49.61%), glutathione peroxidase (178.87%), acetylcholine (25.40%), and klotho (145.57%) were significantly increased than VDD. Conclusions: Study findings supported that CBD interacts with CYP2R1, CYP27B1, CYP24A1, and vitamin D receptors, resulting in increased vitamin D3 metabolites, which improved memory, pain tolerance, reduced inflammation, and aging through modulating antioxidative enzymes, cytokines, and neurotransmitters in VDD-induced rats.


Assuntos
Canabidiol , Colecalciferol , Ratos , Animais , Colecalciferol/farmacologia , Colecalciferol/metabolismo , Receptores de Calcitriol/genética , 25-Hidroxivitamina D3 1-alfa-Hidroxilase/genética , 25-Hidroxivitamina D3 1-alfa-Hidroxilase/metabolismo , Canabidiol/farmacologia , Vitamina D3 24-Hidroxilase/genética , Vitamina D3 24-Hidroxilase/metabolismo , Memória Espacial , Sistema Enzimático do Citocromo P-450 , Inflamação/tratamento farmacológico , Envelhecimento , Dieta , Citocinas , Dor , RNA Mensageiro/metabolismo
9.
Geohealth ; 6(9): e2021GH000449, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35935574

RESUMO

Pathways of transmission of coronavirus (COVID-19) disease in the human population are still emerging. However, empirical observations suggest that dense human settlements are the most adversely impacted, corroborating a broad consensus that human-to-human transmission is a key mechanism for the rapid spread of this disease. Here, using logistic regression techniques, estimates of threshold levels of population density were computed corresponding to the incidence (case counts) in the human population. Regions with population densities greater than 3,000 person per square mile in the United States have about 95% likelihood to report 43,380 number of average cumulative cases of COVID-19. Since case numbers of COVID-19 dynamically changed each day until 30 November 2020, ca. 4% of US counties were at 50% or higher probability to 38,232 number of COVID-19 cases. While threshold on population density is not the sole indicator for predictability of coronavirus in human population, yet it is one of the key variables on understanding and rethinking human settlement in urban landscapes.

10.
J Microbiol Immunol Infect ; 55(6 Pt 1): 1060-1068, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35843834

RESUMO

BACKGROUND: During October 2020, Delta variant was detected for the first time in India and rampantly spread across the globe. It also led to second wave of pandemic in India which affected millions of people. However, there is limited information pertaining to the SARS-CoV-2 strain infecting the children in India. METHODS: Here, we assessed the SARS-CoV-2 lineages circulating in the pediatric population of India during the second wave of the pandemic. Clinical and demographic details linked with the nasopharyngeal/oropharyngeal swabs (NPS/OPS) collected from SARS-CoV-2 cases (n = 583) aged 0-18 year and tested positive by real-time RT-PCR were retrieved from March to June 2021. RESULTS: Symptoms were reported among 37.2% of patients and 14.8% reported to be hospitalized. The E gene CT value had significant statistical difference at the point of sample collection when compared to that observed in the sequencing laboratory. Out of these 512 sequences 372 were VOCs, 51 were VOIs. Most common lineages observed were Delta, followed by Kappa, Alpha and B.1.36, seen in 65.82%, 9.96%, 6.83% and 4.68%, respectively in the study population. CONCLUSION: Overall, it was observed that Delta strain was the leading cause of SARS-CoV-2 infection in Indian children during the second wave of the pandemic. We emphasize on the need of continuous genomic surveillance in SARS-CoV-2 infection even amongst children.


Assuntos
COVID-19 , Humanos , Criança , COVID-19/epidemiologia , SARS-CoV-2/genética , Índia/epidemiologia , Povo Asiático
11.
Antiviral Res ; 205: 105382, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35835290

RESUMO

Japanese encephalitis (JE) is a mosquito-borne flavivirus infection named Japanese Encephalitis Virus (JEV), prevalent in Asia-pacific countries, requires an accurate and rapid diagnosis to contain the outbreak of the disease. In cases of low viral load in early-stage infections, this task becomes difficult. Therefore, we have developed a surface-enhanced Raman spectroscopy (SERS) based biosensor for rapid, sensitive, and early-stage detection of JE antigen. In this work, silver nanoparticles were deposited over a glass coverslip and used as a substrate for designing the sensing platform. Silver Nanoparticles have good metallic properties and plasmon activity. Therefore, it amplifies the Raman signals and provides a suitable surface for the SERS substrate. The developed platform has been used for the detection of the Japanese encephalitis virus (JEV). The fabricated sensor shows a linear response from 5 ng/mL to 80 ng/mL with a limit of detection (LoD) of ∼7.6 ng/mL. Therefore, this method could be a significant addition to the diagnostic modalities for early, sensitive, and specific diagnoses of JE antigen even at the nanogram level.


Assuntos
Vírus da Encefalite Japonesa (Espécie) , Encefalite Japonesa , Nanopartículas Metálicas , Animais , Ásia/epidemiologia , Encefalite Japonesa/diagnóstico , Humanos , Prata
12.
J Appl Microbiol ; 133(3): 1446-1460, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35633293

RESUMO

AIMS: Numerous pre-clinical and clinical studies have recently demonstrated the significant role of phage therapy in treating multidrug-resistant bacterial infections. However, only a few researchers have focused on monitoring the phage-mediated adverse reactions during phage therapy. The present study aimed to demonstrated the oral acute and sub-acute toxicity of bacteriophages (Klebsiella pneumoniae XDR strain) in Charles Foster rats with special reference to immunological response and adverse effects. METHODS AND RESULTS: Bacteriophages were orally administered in dosages of 1010  PFU/ml and a 1015  PFU/ml to Charles Foster rats as a single dose (in acute toxicity study) and daily dosage for 28 days (in sub-acute toxicity study). One millilitre suspension of bacteriophages was administered through the oral gavage feeding tube. No adverse effect was observed in any of the experimental as well as in the control animals. Furthermore, an insignificant change in food and water intake and body weight was observed throughout the study period compared with the control group rats. On the 28th day of phage administration, blood was collected to estimate haematological, biochemical and cytokines parameters. The data suggested no difference in the haematological, biochemical and cytokine profiles compared to the control group. No significant change in any of the treatment groups could be observed on the gross and histopathological examinations. The cytokines estimated, interleukin-1 beta (IL-1ß), IL-4, IL-6 and IFN-gamma, were found within the normal range during the experiment. CONCLUSIONS: The results concluded that no adverse effect, including the severe detrimental impact on oral administration of high (1010 PFU/ml) and very high dose (1015  PFU/ml) of the bacteriophages cocktail. SIGNIFICANCE AND IMPACT OF STUDY: The high and long-term oral administration of bacteriophages did not induce noticeable immunological response as well.


Assuntos
Bacteriófagos , Terapia por Fagos , Animais , Bacteriófagos/fisiologia , Citocinas , Farmacorresistência Bacteriana Múltipla , Klebsiella pneumoniae , Ratos
14.
Inflammopharmacology ; 30(1): 225-232, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34997430

RESUMO

OBJECTIVE: The study objective was to evaluate the therapeutic effect of cannabidiol (CBD) on a combination of caecal slurry, lipopolysaccharide (LPS), and Escherichia coli (E. coli)-induced systemic inflammatory response syndrome (SIRS) in male Sprague Dawley rats. METHODS: The therapeutic activity was monitored in behavioral tests and inflammatory biomarkers by the enzyme-linked immune sorbent assay (ELISA) method. RESULTS: Behavioral tasks were significantly increased like a tail flick response by 73.84% (p ≤ 0.001), grip strength by 33.56% (p ≤ 0.028), locomotor activity by 20.71% (p = 0.034) in the CBD (60 mg/kg) group compared to disease control (DC) group. Levels of inflammatory serum biomarkers like interleukin-1ß (IL-1ß), matrix metallopeptidase-9 (MMP-9), IL-6, and tumor necrosis factor-alpha (TNF-α) were significantly decreased by 29.56 (p = 0.041), 71.20 (p ≤ 0.001), 35.05 (p ≤ 0.001), and 75.56% (p = 0.002), respectively, in the CBD-60 compared with DC. Inflammatory cytokines levels, viz. IL-1ß, MMP-9, IL-6, and TNF-α, in the liver were significantly (p ≤ 0.001) decreased by 81.01, 40.41, 22.84, and 69.46%, respectively, in CBD-60 to DC. Similarly, levels of inflammatory cytokines such as IL-1ß and MMP-9 in the kidney were significantly (p ≤ 0.001) decreased by 80.90 and 43.93%, respectively, in CBD-60 compared to DC. CONCLUSION: Taken together, results suggest that CBD treatment significantly improved behavioral tasks and decreased the level of inflammatory cytokines under SIRS conditions that might provide an opportunity to manage acute and chronic inflammatory disorders.


Assuntos
Canabidiol , Lipopolissacarídeos , Animais , Anti-Inflamatórios/farmacologia , Canabidiol/farmacologia , Citocinas , Escherichia coli , Lipopolissacarídeos/farmacologia , Masculino , Ratos , Ratos Sprague-Dawley , Síndrome de Resposta Inflamatória Sistêmica/tratamento farmacológico , Fator de Necrose Tumoral alfa
15.
Am J Trop Med Hyg ; 106(3): 877-885, 2022 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-35090138

RESUMO

The complexity of transmission of COVID-19 in the human population cannot be overstated. Although major transmission routes of COVID-19 remain as human-to-human interactions, understanding the possible role of climatic and weather processes in accelerating such interactions is still a challenge. The majority of studies on the transmission of this disease have suggested a positive association between a decrease in ambient air temperature and an increase in human cases. Using data from 19 early epicenters, we show that the relationship between the incidence of COVID-19 and temperature is a complex function of prevailing climatic conditions influencing human behavior that govern virus transmission dynamics. We note that under a dry (low-moisture) environment, notably at dew point temperatures below 0°C, the incidence of the disease was highest. Prevalence of the virus in the human population, when ambient air temperatures were higher than 24°C or lower than 17°C, was hypothesized to be a function of the interaction between humans and the built or ambient environment. An ambient air temperature range of 17 to 24°C was identified, within which virus transmission appears to decrease, leading to a reduction in COVID-19 human cases.


Assuntos
COVID-19 , COVID-19/epidemiologia , Humanos , Incidência , SARS-CoV-2 , Temperatura , Tempo (Meteorologia)
16.
Front Cell Infect Microbiol ; 11: 717068, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34804989

RESUMO

This study aimed to detect the SARS-COV2 viral component directly from inoculated VTM without RNA extraction. Inoculated VTMs of already tested 50 positive and 50 negative samples were divided into three groups. Group I was treated with Proteinase K (PK) followed by 3-step-heat treatment at different temperatures (25°C, 60°C, and 98°C) and stored at 4°C. Group II was directly subjected to 3-step-heat treatment without PK exposure and stored at 4°C. And group III was set-up as standard group; it was processed using Qiagen's column based QIAamp Nucleic Acid kit and the obtained nucleic acids were stored at 4°C. These stored samples were used as a template to execute real-time polymerase chain reaction, and results were noted. Group I demonstrated 96% and 88% sensitivity for N and ORF1ab genes respectively, whereas group II demonstrated 78% and 60% when compared to the results of standard group III. Overall group I showed better results than group II when compared to group III. Thus, in situations where gold-standard reagents are not available, PK exposure and heat treatment can be employed to carry out molecular detection of SARS-CoV2 viral component.


Assuntos
COVID-19 , RNA Viral , Endopeptidase K , Humanos , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real , SARS-CoV-2
17.
Environ Microbiol ; 23(12): 7314-7340, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34390611

RESUMO

Vibrio spp. thrive in warm water and moderate salinity, and they are associated with aquatic invertebrates, notably crustaceans and zooplankton. At least 12 Vibrio spp. are known to cause infection in humans, and Vibrio cholerae is well documented as the etiological agent of pandemic cholera. Pathogenic non-cholera Vibrio spp., e.g., Vibrio parahaemolyticus and Vibrio vulnificus, cause gastroenteritis, septicemia, and other extra-intestinal infections. Incidence of vibriosis is rising globally, with evidence that anthropogenic factors, primarily emissions of carbon dioxide associated with atmospheric warming and more frequent and intense heatwaves, significantly influence environmental parameters, e.g., temperature, salinity, and nutrients, all of which can enhance growth of Vibrio spp. in aquatic ecosystems. It is not possible to eliminate Vibrio spp., as they are autochthonous to the aquatic environment and many play a critical role in carbon and nitrogen cycling. Risk prediction models provide an early warning that is essential for safeguarding public health. This is especially important for regions of the world vulnerable to infrastructure instability, including lack of 'water, sanitation, and hygiene' (WASH), and a less resilient infrastructure that is vulnerable to natural calamity, e.g., hurricanes, floods, and earthquakes, and/or social disruption and civil unrest, arising from war, coups, political crisis, and economic recession. Incorporating environmental, social, and behavioural parameters into such models allows improved prediction, particularly of cholera epidemics. We have reported that damage to WASH infrastructure, coupled with elevated air temperatures and followed by above average rainfall, promotes exposure of a population to contaminated water and increases the risk of an outbreak of cholera. Interestingly, global predictive risk models successful for cholera have the potential, with modification, to predict diseases caused by other clinically relevant Vibrio spp. In the research reported here, the focus was on environmental parameters associated with incidence and distribution of clinically relevant Vibrio spp. and their role in disease transmission. In addition, molecular methods designed for detection and enumeration proved useful for predictive modelling and are described, namely in the context of prediction of environmental conditions favourable to Vibrio spp., hence human health risk.


Assuntos
Vibrioses , Vibrio , Meio Ambiente , Humanos , Incidência , Vibrio/classificação , Vibrio/patogenicidade , Vibrioses/epidemiologia , Vibrioses/transmissão
18.
Biomed Res Int ; 2021: 6653950, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34124257

RESUMO

The study is aimed at establishing the optimal parameters for RNA purification of pooled specimens, in SARS-CoV-2 assay. This research work evaluates the difference of extracted RNA purity of pooled samples with and without treatment with isopropyl alcohol and its effect on real-time RT-PCR. As per the protocol of the Indian Council of Medical Research (ICMR), 5 sample pools were analysed using qRT-PCR. A total of 100 pooled samples were selected for the study by mixing 50 µL of one COVID-19 positive nasopharyngeal/oropharyngeal (NP/OP) specimen and 50 µL each of 4 known negative specimens. Pool RNA was extracted using the column-based method, and 1 set of pooled extracted RNA was tested as such, while RNA of the second set was treated additionally with chilled isopropyl alcohol (modified protocol). Further, the purity of extracted RNA in both the groups was checked using Microvolume Spectrophotometers (Nanodrop) followed by RT-PCR targeting E-gene and RNaseP target. The results showed that the purity index of extracted RNA of untreated pooled specimens was inferior to isopropyl alcohol-treated templates, which was observed to be 85% sensitivity and 100% specificity. The average Cq (E gene) in the unpurified and purified pool RNA group was 34.66 and 31.48, respectively. The nanodrop data suggested that purified RNA concentration was significantly increased with an average value of 24.73 ± 1.49 ng/uL, which might be the reason for high sensitivity and specificity. Thus, this group testing of SARS-CoV-2 cases using pools of 5 individual samples would be the best alternative for saving molecular reagents, personnel time, and can increase the overall testing capacity. However, purity of RNA is one of the important determinants to procure unfailing results, thus, this additional purification step must be included in the protocol after RNA has been extracted using commercially available kit before performing qRT-PCR.


Assuntos
COVID-19/diagnóstico , Proteínas do Envelope de Coronavírus/genética , RNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/métodos , SARS-CoV-2/genética , 2-Propanol/química , Biomarcadores/análise , COVID-19/virologia , Primers do DNA/síntese química , Primers do DNA/genética , Humanos , Nasofaringe/virologia , Orofaringe/virologia , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real/economia , Reação em Cadeia da Polimerase em Tempo Real/normas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
19.
Front Pharmacol ; 12: 615445, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33912038

RESUMO

Numerous pre-clinical and clinical studies have recently demonstrated the significant role of phage therapy in treating multidrug-resistant bacterial infections. However, only a few researchers have focused on monitoring the phage-mediated adverse reactions during phage therapy. Besides adverse reactions, immunological response after short- and long-term oral administration of bacteriophages is also lacking. In this study, we administered the bacteriophages orally against Klebsiella pneumoniae XDR strain in dosages of 1015 PFU/ml and a 1020 PFU/ml (still higher) to Charles Foster rats as a single dose (in acute toxicity study) and daily dosage for 28 days (in sub-acute toxicity study). One milliliter suspension of bacteriophages was administered through the oral gavage feeding tube. No adverse effect was observed in any of the experimental as well as in the control animals.Further, an insignificant change in food and water intake and body weight was observed throughout the study period compared with the control group rats. On the 28th day of phage administration, blood was collected to estimate hematological, biochemical, and cytokines parameters. The data suggested no difference in the hematological, biochemical, and cytokine profile compared to the control group. No significant change in any of the treatment groups could be observed on the gross and histopathological examinations. The cytokines estimated, interleukin-1 beta (IL-1ß), IL-4, IL-6, and INF-gamma, were found within the normal range during the experiment. The results suggested no adverse effect, including the severe detrimental impact on oral administration of high (1015 PFU/ml) and very high dose (1020 PFU/ml) of the bacteriophages cocktail. The high and long-term oral administration of bacteriophages did not induce noticeable immunological response as well.

20.
Int J Infect Dis ; 100: 476-482, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32949774

RESUMO

OBJECTIVES: Because the detection of SARS-CoV-2 RNA in aerosols but failure to isolate viable (infectious) virus are commonly reported, there is substantial controversy whether severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can be transmitted through aerosols. This conundrum occurs because common air samplers can inactivate virions through their harsh collection processes. We sought to resolve the question whether viable SARS-CoV-2 can occur in aerosols using VIVAS air samplers that operate on a gentle water vapor condensation principle. METHODS: Air samples collected in the hospital room of two coronavirus disease-2019 (COVID-19) patients, one ready for discharge and the other newly admitted, were subjected to RT-qPCR and virus culture. The genomes of the SARS-CoV-2 collected from the air and isolated in cell culture were sequenced. RESULTS: Viable SARS-CoV-2 was isolated from air samples collected 2 to 4.8 m away from the patients. The genome sequence of the SARS-CoV-2 strain isolated from the material collected by the air samplers was identical to that isolated from the newly admitted patient. Estimates of viable viral concentrations ranged from 6 to 74 TCID50 units/L of air. CONCLUSIONS: Patients with respiratory manifestations of COVID-19 produce aerosols in the absence of aerosol-generating procedures that contain viable SARS-CoV-2, and these aerosols may serve as a source of transmission of the virus.


Assuntos
Microbiologia do Ar , Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/virologia , Pneumonia Viral/virologia , Aerossóis , COVID-19 , Infecções por Coronavirus/transmissão , Hospitais , Humanos , Pandemias , Pneumonia Viral/transmissão , SARS-CoV-2
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