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1.
BMC Infect Dis ; 22(1): 38, 2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-34991508

RESUMO

BACKGROUND: Influenza A virus (IAV) remains an important global public health threat with limited epidemiological information available from low-and-middle-income countries. The major objective of this study was to describe the proportions, temporal and spatial distribution, and demographic and clinical characteristics of IAV positive patients with influenza like illness (ILI) and severe acute respiratory illness (SARI) in Lahore, Pakistan. METHODS: Prospective surveillance was established in a sentinel hospital from October 2015 to May 2016. All eligible outpatients and inpatients with ILI or SARI were enrolled in the study. Nasal and/or throat swabs were collected along with clinico-epidemiological data. Samples were tested by real-time RT-PCR (rRT-PCR) to identify IAV and subtype. The descriptive analysis of data was done in R software. RESULTS: Out of 311 enrolled patients, 284 (91.3%) were ILI and 27 (8.7%) were SARI cases. A distinct peak of ILI and SARI activity was observed in February. Fifty individuals (16%) were positive for IAV with peak positivity observed in December. Of 50 IAV, 15 were seasonal H3N2, 14 were H1N1pdm09 and 21 were unable to be typed. The majority of IAV positive cases (98%) presented with current or history of fever, 88% reported cough and 82% reported sore throat. The most common comorbidities in IAV positive cases were hepatitis C (4%), obesity (4%) and tuberculosis (6%). The highest incidence of patients reporting to the hospital was seen three days post symptoms onset (66/311) with 14 of these (14/66) positive for IAV. CONCLUSION: Distinct trends of ILI, SARI and IAV positive cases were observed which can be used to inform public health interventions (vaccinations, hand and respiratory hygiene) at appropriate times among high-risk groups. We suggest sampling from both ILI and SARI patients in routine surveillance as recommended by WHO.


Assuntos
Vírus da Influenza A , Influenza Humana , Humanos , Lactente , Vírus da Influenza A Subtipo H3N2 , Influenza Humana/epidemiologia , Paquistão/epidemiologia , Estudos Prospectivos , Estações do Ano , Vigilância de Evento Sentinela
2.
S D Med ; 75(10): 462-468, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36889272

RESUMO

INTRODUCTION: Group B Streptococcus (GBS) positive patients with penicillin allergies receive intrapartum antibiotics for neonatal sepsis prophylaxis based on recommendations from the American College of Obstetricians and Gynecologists (ACOG). The objective of this study was to determine which antibiotics are used in GBS positive patients with documented penicillin allergies and evaluate for antibiotic stewardship improvements at a tertiary hospital in the Midwestern U.S. METHODS: Retrospective chart review identified GBS positive patients with and without penicillin allergies admitted to the labor and delivery floor. EMR-documented penicillin allergy severity, results of antibiotic susceptibility testing, and all antibiotics administered from admission to delivery were recorded. The study population was divided based on penicillin allergy status with antibiotic choice analyzed using Fisher's exact test. RESULTS: 406 GBS positive patients underwent labor between May 1, 2019, and April 30, 2020. Penicillin allergy was documented in 62 (15.3 percent) patients. Of these patients, cefazolin and vancomycin were prescribed most frequently for intrapartum neonatal sepsis prophylaxis. Antibiotic susceptibility testing was performed on the GBS isolate in 74.2 percent of the penicillin allergic patients. Between penicillin allergy and no penicillin allergy groups, the frequency of ampicillin, cefazolin, clindamycin, gentamicin, and vancomycin use showed statistical differences. CONCLUSION: The study results suggest that antibiotic choice for neonatal sepsis prophylaxis in GBS positive patients with penicillin allergy at a tertiary Midwestern hospital follows current ACOG guidelines. Cefazolin was used most frequently in this population followed by vancomycin and clindamycin. Our results identify room for improvement regarding regular antibiotic susceptibility testing in GBS positive patients with penicillin allergy.


Assuntos
Hipersensibilidade a Drogas , Hipersensibilidade , Sepse Neonatal , Complicações Infecciosas na Gravidez , Infecções Estreptocócicas , Gravidez , Feminino , Recém-Nascido , Humanos , Antibacterianos/efeitos adversos , Cefazolina/uso terapêutico , Clindamicina/uso terapêutico , Vancomicina/uso terapêutico , Estudos Retrospectivos , Sepse Neonatal/tratamento farmacológico , Antibioticoprofilaxia/métodos , Complicações Infecciosas na Gravidez/tratamento farmacológico , Complicações Infecciosas na Gravidez/prevenção & controle , Infecções Estreptocócicas/tratamento farmacológico , Infecções Estreptocócicas/prevenção & controle , Streptococcus agalactiae , Penicilinas/efeitos adversos , Hipersensibilidade a Drogas/tratamento farmacológico , Hipersensibilidade a Drogas/epidemiologia , Hipersensibilidade/tratamento farmacológico
3.
Crit Rev Eukaryot Gene Expr ; 31(2): 55-62, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34347979

RESUMO

Sphingomonas sp. Shah is a bacterium that was first isolated from mammalian cell cultures. According to ribotyping data it is very much homologous to the clinically important pathogen Sphingomonas paucimobilis, which has generated pseudo-outbreaks. Using a tissue culture system, Sphingomonas sp. Shah was discovered to induce apoptosis in human lung epithelial carcinoma. Apoptosis of infected cells was determined by numerous criteria including (1) visual alterations in cellular morphology, (2) initiation of nuclear marginalization and chromatin compaction condensation, (3) the attendance of a high percentage of cells with subG1 DNA content, and (4) caspase-3 activation. In the current study we demonstrate the induction of apoptosis in mammalian lung epithelial cells upon infection with Sphingomonas sp. Shah and provide insight into the molecular processes triggering apoptosis.


Assuntos
Apoptose/fisiologia , Meios de Cultura , Pulmão/citologia , Sphingomonas/isolamento & purificação , Células A549 , Apoptose/genética , Células Epiteliais/citologia , Genes Bacterianos , Humanos , Filogenia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sphingomonas/classificação , Sphingomonas/genética , Sphingomonas/fisiologia
4.
Can J Infect Dis Med Microbiol ; 2021: 2460553, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34745395

RESUMO

Epidemiological data about determinants of influenza A virus (IAV) in the Pakistani population is scarce. We aimed to conduct a prospective hospital-based active surveillance study from October 2015 to May 2016 to identify potential risk factors associated with IAV infection among patients with influenza-like illness (ILI) and severe acute respiratory illness (SARI). Surveillance was conducted in Lahore General Hospital, selected as a sentinel site in Lahore District, Pakistan. Nasal/throat samples were collected along with epidemiological and clinical data from enrolled patients. Real-time reverse-transcription polymerase chain reaction (rRT-PCR) was performed to identify IAV and its subtypes (H1N1pdm09, H3N2). Data were analyzed to determine risk factors and risk markers associated with IAV infections. A total of 311 suspected ILI and SARI cases were enrolled in the study, and among these 50 were IAV-positive. Of these 50 confirmed cases of IAV, 14 were subtyped as H1N1pdm09 and 15 were H3N2; the remaining 21 were untyped. A final multivariable model identified four independent risk factors/markers for IAV infection: exposure history to ILI patients within last 7 days and gender being male were identified as risk factors of IAV infection, while use of antibiotics prior to hospital consultation and presence of fever were identified as risk markers. We concluded that adopting nonpharmaceutical interventions like hand hygiene, masks, social distancing, and where possible, avoiding identified risk factors could decrease the risk of IAV infection and may prevent imminent outbreaks of IAV in the community.

5.
S D Med ; 73(12): 575-581, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33684977

RESUMO

INTRODUCTION: Patients with self-reported penicillin allergies frequently receive unnecessary broad-spectrum antibiotics, which are associated with poor outcomes for patients and healthcare systems. The objective of this study was to determine the significance of broad-spectrum antibiotic prescription among patients with a documented penicillin allergy. METHODS: Retrospective chart review identified a cohort of penicillin allergic patients admitted to the primary medical-surgical floors at Avera McKennan that received intravenous or oral antibiotics. We recorded the allergy manifestation and severity, and all antibiotics administered within 24 hours of admission. The cohort was further divided into various subgroups and analyzed using Chi-Square or a Fischer's exact test. RESULTS: 190 patients with documented penicillin allergies received antibiotics between Dec. 1, 2018, and March 31, 2019. A severe penicillin allergy was documented in 86.3 percent of cases. Cephalosporins, vancomycin, and fluoroquinolones represented 34.1 percent, 18.2 percent, and 12.7 percent of initial antibiotics, respectively. No significance was noted in the comparison of antibiotic choice between patients with a specified versus an unspecified penicillin allergy. The number of cephalosporin prescriptions was significantly lower in a surgical prophylaxis subgroup of patients compared to a non-surgical prophylaxis subgroup. CONCLUSION: Our study supports literature suggesting patients with documented penicillin allergies are at risk of unwarranted broad-spectrum antibiotic use. We noted an alarming number of unverified penicillin allergies. Prescription patterns did not appear to be altered based on verification or type of recorded allergic reaction. Surgical patients may be at greater risk. Our findings call for heightened antibiotic stewardship especially regarding patients with a documented penicillin allergy.


Assuntos
Antibacterianos , Hipersensibilidade a Drogas , Antibacterianos/efeitos adversos , Cefalosporinas , Hipersensibilidade a Drogas/epidemiologia , Humanos , Penicilinas/efeitos adversos , Estudos Retrospectivos
6.
S D Med ; 73(7): 312-317, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32805781

RESUMO

BACKGROUND: We aim to describe the basic demographics, clinical course and outcomes of critically ill patients with Covid-19 admitted to Avera McKennan Hospital and University Health Center Intensive Care Unit (ICU) between March 20 and May 4, 2020. METHODS: In this single centered, retrospective, observational study, we enrolled 37 critically ill adults with COVID-19 pneumonia admitted to the (ICU) between March 20 and May 4, 2020. Demographic data, admitting symptoms, laboratory values, co-morbidities, treatments and clinical outcomes were collected. Data was compared between survivors and non-survivors. We aim to describe our data and report the 28-day mortality as of June 1, 2020. RESULTS: Of 154 patients admitted with COVID-19 pneumonia during our study period, 37 (24 percent) were critically ill and required an ICU stay. The mean age was 58 years and 76 percent were men. Of these 37 patients, 28 (78 percent) had a chronic illness (diabetes in 43 percent, hypertension in 47 percent). In addition, 54 percent were associated with a local meat packing plant. Most common presenting symptoms were dyspnea (92 percent), cough (70 percent) and fever (68 percent). The mean PaO2/ FiO2 ratio was 143 (67-362). Significant lab findings include the following: 54 percent of patients had lymphocytopenia, the mean ferritin was 850 ng/mL (10-3528), the mean D-Dimer was 4.09 FEU ug/mL and the mean IL-6 was 96.5 pg/mL. At 28 days, 24 percent (nine) had died. Twenty-five (68 percent) patients required mechanical ventilation, with 10 (27 percent) of those patients requiring initiation of neuromuscular blocking agents for ventilator compliance. Of those four (40 percent) did not survive. In addition, 20 patients (54 percent) were proned. Pneumomediastinum or pneumothorax occurred in five of the 37 (14 percent). Renal replacement therapy was required in 6 of the 37 patients, 4 of whom (66 percent) died. Steroids were used in 70 percent of patients, tocilizumab in 59 percent, and hydroxychloroquine in 27 percent. All patients received antibiotics. Convalescent plasma became available for our 5th patient. A total of 29 (78 percent) received convalescent plasma, (86 percent of survivors and 56 percent non-survivors). Median ICU length of stay was 11 days for both survivors (1-49) and non-survivors (1-21). There were no differences in age, body mass index (BMI), or initial PaO2/FiO2 (P/F) among those two groups. Non-survivors (nine) included the two immune compromised patients in our cohort, two patients with pre-existing DNR/DNI status, and one death within two hours of admit. Compared with survivors, more of the non-survivors received vasopressors (78 percent vs 46 percent), dialysis (44 percent vs 7 percent) and hydroxychloroquine (44 percent vs 21 percent). The first 5 patients treated in the ICU did not survive. One month after the initial case was reported in South Dakota, our ICU experienced a six-week surge. At its highest, COVID-19-related census reached 63 percent of the ICU capacity (15/24). CONCLUSION: Mortality of critically ill patients with COVID-19 is high. Multi-organ, advanced and prolonged critical care resources are needed. Interpretation of our data is limited by a higher mortality of the earlier members of the cohort, a change in therapeutic practice over time and institution of social distancing.


Assuntos
Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/mortalidade , Estado Terminal , Pneumonia Viral/diagnóstico , Pneumonia Viral/mortalidade , Betacoronavirus , COVID-19 , Comorbidade , Feminino , Humanos , Masculino , Indústria de Embalagem de Carne , Pessoa de Meia-Idade , Pandemias , Estudos Retrospectivos , SARS-CoV-2 , South Dakota/epidemiologia
7.
Arch Virol ; 163(8): 2179-2188, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29707734

RESUMO

Given the global evolutionary dynamics of Newcastle disease viruses (NDVs), it is imperative to continue extensive surveillance, routine monitoring and characterization of isolates originating from natural reservoirs (waterfowls). In this report, we isolated and characterized two virulent NDV strains from clinically healthy mallard (Anas platyrhynchos). Both isolates had a genome of 15,192 nucleotides encoding six genes in an order of 3´-NP-P-M-F-HN-L-5´. The biological characteristics (mean death time: 49.5-50 hr, EID50108.5 ml-1) and presence of a typical cleavage site in the fusion (F) protein (112R-R-Q-K-R↓F117) confirmed the velogenic nature of these isolates. Phylogenetic analysis classified both isolates as members of genotype VII within class-II. Furthermore, based upon the hypervariable region of the F gene (375 nt), isolates showed clustering within sub-genotype VIIi. Similarity index and parallel comparison revealed a higher nucleotide divergence from commonly used vaccine strains; LaSota (21%) and Mukteswar (17%). A comparative residues analysis with representative strains of different genotypes, including vaccine strains, revealed a number of substitutions at important structural and functional domains within the F and hemagglutinin-neuraminidase (HN) proteins. Together, the results highlight consistent evolution among circulating NDVs supporting extensive surveillance of the virus in waterfowl to better elucidate epidemiology, evolutionary relationships and their impacts on commercial and backyard poultry.


Assuntos
Doença de Newcastle/virologia , Vírus da Doença de Newcastle/genética , Migração Animal , Animais , Animais Selvagens/fisiologia , Animais Selvagens/virologia , Patos , Genoma Viral , Genômica , Genótipo , Doença de Newcastle/fisiopatologia , Vírus da Doença de Newcastle/classificação , Vírus da Doença de Newcastle/isolamento & purificação , Vírus da Doença de Newcastle/fisiologia , Filogenia , Doenças das Aves Domésticas/virologia , Proteínas Virais/genética
8.
J Cell Biochem ; 116(6): 934-42, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25559735

RESUMO

A novel contaminant was isolated from Madin Darby Bovine Kidney (MDBK) cells. The organism was unable to grow on standard microbiological media by conventional techniques, but grew well in Dulbecco's Modified Eagle's Medium (DMEM) containing high glucose concentration. The organism formed a white biofilm on the bottom without any signs of turbidity. Upon genome sequence analysis of 16 S rDNA, the contaminant was identified as Sphingomonas sp. Shah, a member of the group α-Proteobacteria. Neutral red dye uptake method confirmed clear cytotoxic potential of the bacterium on A-549 cells. The organism was capable of invading and infecting different mammalian cell lines: MDBK, ZZ-R, 293-T, A549, and HeLa cells. Infected cells showed a variety of cytopathic effects including vacuolation at perinuclear area, cytoplasmic granulation and membrane blebbing. Microscopic analysis of the infected cells revealed the presence of cytoplasmic vacuoles harboring motile organisms. Apparently local serum preparations seem to be the source of this contamination, which is imperceptibly passed on from one culture passage to the other and ultimately leading to serious cytopathic manifestations.


Assuntos
Técnicas de Cultura de Células/métodos , Sphingomonas/citologia , Sphingomonas/isolamento & purificação , Animais , Bovinos , Linhagem Celular , Linhagem Celular Tumoral , Células Cultivadas , Células HeLa , Humanos , Masculino , Pessoa de Meia-Idade
9.
J Food Sci Technol ; 52(8): 5323-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26243960

RESUMO

A total of 300 meat samples comprising mutton, beef, and chicken meat (n = 100) collected from either local butcher shops or large meat outlets situated at various areas of Lahore City located in Punjab province of Pakistan were tested for the isolation of Clostridium perfringens. Prevalence of the organism was highest in the chicken (6 %) followed by mutton (5 %) and beef (1 %). Contamination level was high (10/150) in the samples collected from local butcher shops in comparison to the samples collected from large meat outlets (2/150). All of the raw meat samples were negative for the presence of alpha, beta and epsilon toxins of C. perfringens as detected through ELISA. Out of a total number of 12 isolates only half were capable of producing enterotoxins when cultured in trypticase glucose yeast (TGY) broth. Toxinotyping of the isolates showed that 3 were of type A while one each of the remaining three belonged to type B, C, and D. Antibiotic susceptibility testing of the toxin producing isolates revealed that C. perfringens were susceptible to chloramphenicol, ciprofloxacin, metronidazole, and ceftriaxone. All of the other drugs were relatively less effective with a least activity of amoxicillin against the isolates.

10.
Pak J Pharm Sci ; 28(3): 997-1004, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26004734

RESUMO

Vancomycin resistant Staphylococcus aureus (VRSA) has been reported from many parts of the world including Asian countries. Hence, main objective of study was to evaluate the possible occurrence of VRSA in hospitals of Lahore city and to ensure the effectiveness of various substitute therapeutic options. A total of 150 samples of pus/wounds were collected from three hospitals of the city and VRSA were isolated and confirmed through recommended method of Clinical and Laboratory Standards Institute. Out of 51 (49.04%) methicillin resistant S. aureus (MRSA) isolates, 5 (9.8%) were found resistant to vancomycin. Minimum inhibitory concentration (MIC) of Linezolid (LZD), Moxifloxacin (MFX) and Clindamycin (CD) were calculated against VRSA isolates by broth microdilution test. All 5 (100%) isolates were susceptible to Linezolid and Clindamycin, while 4 (80%) were susceptible to Moxifloxacin. Ethanolic extracts of Turmeric, Mint, Coriander, Garlic, Kalonji, Cinnamon and Cloves illustrate average MIC values of 140.8 µg/mL, 563.2 µg/mL, 486.4 µg/mL, 614.4 µg/mL, 409.6 µg/mL, 281.6 µg/mL and 64 µg/mL, respectively against 5 VRSA strains. Concentration dependent increase in growth inhibition zones of ethanolic plant extract was recorded by agar well diffusion test. This study was helpful to find out the effective antibiotic against VRSA. Plant extracts encompass anti-staphylococcal activity and this finding demands necessity of further exploration of potential found in these natural herb.


Assuntos
Acetamidas/farmacologia , Antibacterianos/farmacologia , Clindamicina/farmacologia , Fluoroquinolonas/farmacologia , Oxazolidinonas/farmacologia , Extratos Vegetais/farmacologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Infecção da Ferida Cirúrgica/microbiologia , Resistência a Vancomicina , Cinnamomum zeylanicum , Curcuma , Alho , Humanos , Linezolida , Mentha , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Moxifloxacina , Nigella sativa , Paquistão , Staphylococcus aureus/isolamento & purificação , Syzygium , Infecção dos Ferimentos/microbiologia
11.
Virol J ; 10: 170, 2013 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-23721461

RESUMO

BACKGROUND: Newcastle disease (ND) is one of the most deadly diseases of poultry around the globe. The disease is endemic in Pakistan and recurrent outbreaks are being reported regularly in wild captive, rural and commercial poultry flocks. Though, efforts have been made to characterize the causative agent in some of parts of the country, the genetic nature of strains circulating throughout Pakistan is currently lacking. MATERIAL AND METHODS: To ascertain the genetics of NDV, 452 blood samples were collected from 113 flocks, originating from all the provinces of Pakistan, showing high mortality (30-80%). The samples represented domesticated poultry (broiler, layer and rural) as well as wild captive birds (pigeons, turkeys, pheasants and peacock). Samples were screened with real-time PCR for both matrix and fusion genes (1792 bp), positive samples were subjected to amplification of full fusion gene and subsequent sequencing and phylogenetic analysis. RESULTS: The deduced amino acid sequence of the fusion protein cleavage site indicated the presence of motif (112RK/RQRR↓F117) typical for velogenic strains of NDV. Phylogenetic analysis of hypervariable region of the fusion gene indicated that all the isolates belong to lineage 5 of NDV except isolates collected from Khyber Pakhtunkhwa (KPK) province. A higher resolution of the phylogenetic analysis of lineage 5 showed the distribution of Pakistani NDV strains to 5b. However, the isolates from KPK belonged to lineage 4c; the first report of such lineage from this province. CONCLUSIONS: Taken together, data indicated the prevalence of multiple lineages of NDV in different poultry population including wild captive birds. Such understanding is crucial to underpin the nature of circulating strains of NDV, their potential for interspecies transmission and disease diagnosis and control strategies.


Assuntos
Variação Genética , Doença de Newcastle/epidemiologia , Doença de Newcastle/virologia , Vírus da Doença de Newcastle/classificação , Vírus da Doença de Newcastle/genética , Animais , Aves , Análise por Conglomerados , Genótipo , Epidemiologia Molecular , Dados de Sequência Molecular , Vírus da Doença de Newcastle/isolamento & purificação , Paquistão/epidemiologia , Filogenia , Aves Domésticas , RNA Viral/genética , Análise de Sequência de DNA , Proteínas Virais de Fusão/genética
12.
BMC Vet Res ; 9: 60, 2013 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-23537146

RESUMO

BACKGROUND: Peste des petits ruminants (PPR) is an endemic and highly contagious disease in small ruminants of Pakistan. Despite the fact that an effective vaccine is available, outbreaks are regularly occurring in the country. Thus so far, the diagnosis has primarily been made based on clinical outcome or serology. This study was carried out to characterize PPRV from an emerging wave of outbreaks from Punjab, Pakistan. RESULTS: A total of 32 blood samples from five different flocks were tested with real-time PCR for the presence of PPRV genome. The samples detected positive in real-time PCR (n = 17) were subjected to conventional PCR for the amplification of the nucleoprotein (N) gene. Phylogenetic analysis of the sequenced N genes (n = 8) indicated the grouping of all the sequences in lineage IV along with PPRV strains from Asian and Middle East. However, interestingly sequences were divided into two groups. One group of viruses (n = 7) clustered with previously characterized Pakistani isolates whereas one strain of PPRV was distinct and clustered with Saudi Arabian and Iranian strains of PPRV. CONCLUSIONS: Results demonstrated in this study expanded the information on the genetic nature of different PPRV population circulating in small ruminants. Such information is essential to understand genetic nature of PPRV strains throughout the country. Proper understanding of these viruses will help to devise control strategies in PPRV endemic countries such as Pakistan.


Assuntos
Peste dos Pequenos Ruminantes/virologia , Vírus da Peste dos Pequenos Ruminantes/genética , Animais , Sequência de Bases , Surtos de Doenças/veterinária , Genes Virais/genética , Dados de Sequência Molecular , Paquistão/epidemiologia , Peste dos Pequenos Ruminantes/epidemiologia , Filogenia , Reação em Cadeia da Polimerase em Tempo Real/veterinária
13.
Intervirology ; 55(5): 365-71, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22269863

RESUMO

OBJECTIVE: To determine the role of water fleas in accumulating avian influenza viruses (AIV) from the surrounding water and to estimate their role as a vector of AIV. METHODS: Water fleas were exposed to H4N6 and H5N1 AIV-contaminated water in a closed system. The potential of water fleas to take up and retain the viruses was estimated by quantitative real-time RT-PCR (qRRT-PCR) and titration on cell culture. RESULTS: Contamination trials showed that significantly higher amounts of viral RNA were detectable per gram of water fleas as compared to per milliliter of the surrounding water at 1, 4, and 6 days of incubation. Viral infectivity was only detectable in the water samples collected immediately after mixing the virus in water containing the water fleas, while no virus was detectable in any of the water fleas or water samples collected afterwards. CONCLUSIONS: Water fleas are able to accumulate AIV from surrounding water based upon the qRRT-PCR detection of viral RNA. Additional studies are necessary to investigate the inactivation potential of water fleas on viral infectivity.


Assuntos
Cladocera/virologia , Vetores de Doenças , Vírus da Influenza A/isolamento & purificação , Influenza Aviária/virologia , Microbiologia da Água , Animais , Aves , RNA Viral/análise , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real , Carga Viral
14.
Appl Environ Microbiol ; 77(14): 4981-5, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21622783

RESUMO

The persistence of 3 low-pathogenicity avian influenza viruses (LPAIV) (H4N6, H5N1, and H6N8) and one human influenza virus (H1N1) as well as Newcastle disease virus (NDV) and enteric cytopathogenic bovine orphan (ECBO) virus was investigated in lake sediment, duck feces, and duck meat at 30, 20, 10, and 0°C using a germ carrier technique. Virus-loaded germ carriers were incubated in each substrate, and residual infectivity of the eluted virus was quantified on cell culture after regular intervals for a maximum of 24 weeks. Data were analyzed by a linear regression model to calculate T(90) values (time required for 90% loss of virus infectivity) and estimated persistence of the viruses. In general, the persistence of all of the viruses was highest in lake sediment, followed by feces, and was the lowest in duck meat at all temperatures. For the avian influenza virus subtypes, T(90) values in sediment ranged from 5 to 11, 13 to 18, 43 to 54, and 66 to 394 days at 30, 20, 10, and 0°C, respectively, which were 2 to 5 times higher than the T(90) values of the viruses in the feces and meat. Although the individual viruses vary in tenacity, the survival time of influenza viruses was shorter than that of NDV and ECBO virus in all substrates. The results of this study suggest that lake sediment may act as a long-term source of influenza viruses in the aquatic habitat, while the viruses may remain infectious for extended periods of time in duck feces and meat at low temperatures, allowing persistence of the viruses in the environment over winter.


Assuntos
Patos/virologia , Sedimentos Geológicos/virologia , Vírus da Influenza A/isolamento & purificação , Influenza Aviária/epidemiologia , Lagos/virologia , Animais , Fezes/virologia , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Virus da Influenza A Subtipo H5N1/isolamento & purificação , Influenza Aviária/virologia , Carne/virologia , Vírus da Doença de Newcastle/isolamento & purificação
15.
Viruses ; 13(3)2021 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-33668224

RESUMO

Japanese encephalitis (JE) is a vaccine-preventable disease caused by the Japanese encephalitis virus (JEV), which is primarily prevalent in Asia. JEV is a Flavivirus, classified into a single serotype with five genetically distinct genotypes (I, II, III, IV, and V). JEV genotype III (GIII) had been the most dominant strain and caused numerous outbreaks in the JEV endemic countries until 1990. However, recent data shows the emergence of JEV genotype I (GI) as a dominant genotype and it is gradually displacing GIII. The exact mechanism of this genotype displacement is still unclear. The virus can replicate in mosquito vectors and vertebrate hosts to maintain its zoonotic life cycle; pigs and aquatic wading birds act as an amplifying/reservoir hosts, and the humans and equines are dead-end hosts. The important role of pigs as an amplifying host for the JEV is well known. However, the influence of other domestic animals, especially birds, that live in high abundance and close proximity to the human is not well studied. Here, we strive to briefly highlight the role of birds in the JEV zoonotic transmission, discovery of birds as a natural reservoirs and amplifying host for JEV, species of birds susceptible to the JEV infection, and the proposed effect of JEV on the poultry industry in the future, a perspective that has been neglected for a long time. We also discuss the recent in vitro and in vivo studies that show that the newly emerged GI viruses replicated more efficiently in bird-derived cells and ducklings/chicks than GIII, and an important role of birds in the JEV genotype shift from GIII to GI.


Assuntos
Aves/virologia , Vírus da Encefalite Japonesa (Espécie)/patogenicidade , Encefalite Japonesa/transmissão , Encefalite Japonesa/virologia , Mosquitos Vetores/virologia , Animais , Genótipo , Humanos
16.
Avian Dis ; 54(4): 1183-90, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21313838

RESUMO

In order to investigate the potential role of mussels as a vector of influenza A viruses, we exposed zebra mussels (Dreissena polymorpha) to natural lake water containing a low pathogenic H5N1 avian influenza virus. Mussels were kept in water containing virus for 48 hr, then transferred into fresh water for another 14 days. Virus detection in mussels and water samples was performed by quantitative real-time reverse transcriptase-PCR (qRRT-PCR) and egg culture methods. Virus uptake was detected in all of the mussel groups that were exposed to virus. Even after 14 days in fresh water, virus could still be detected in shellfish material by both qRRT-PCR and egg culture methods. The present study demonstrates that zebra mussels are capable of accumulating influenza A viruses from the surrounding water and that these viruses remain in the mussels over an extended period of time.


Assuntos
Dreissena/virologia , Água Doce/virologia , Virus da Influenza A Subtipo H5N1/fisiologia , Influenza Aviária , Microbiologia da Água , Animais , Aves , Influenza Aviária/transmissão , Influenza Aviária/virologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
17.
Avian Dis ; 54(1 Suppl): 720-4, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20521721

RESUMO

The tenacity of three low pathogenicity avian influenza viruses (AIV; subtypes H4N6, H5N1, and H6N8) was tested at five different temperatures (-10, 0, 10, 20, and 30 C) in distilled water, normal saline, and surface water obtained from Lake Constance. Infectivity of AIV in the samples was quantified at regular intervals by end point titration on Madin-Darby canine kidney cells for a maximum period of 36 wk, and duplicate samples were tested each time. The results showed that the survival time of AIV in all of the water types was inversely proportional to storage temperature. All three viruses showed varying sensitivity to inactivation under each of the experimental conditions. Persistence of the viruses was the longest in distilled water, second longest in normal saline, and shortest in surface water. The virus-inoculated surface water remained infective for a few days at 30 and 20 C, a few weeks at 10 C, and for months at 0 and -10 C.


Assuntos
Vírus da Influenza A/fisiologia , Cloreto de Sódio/química , Temperatura , Microbiologia da Água , Água/química , Animais , Linhagem Celular , Embrião de Galinha , Cães , Vírus da Influenza A/classificação , Vírus da Influenza A/patogenicidade , Fatores de Tempo
18.
Transplant Proc ; 52(9): 2790-2794, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32641222

RESUMO

Cryptococcal infection (CI) is an uncommon fungal disease that poses a particular fatal risk to liver transplant (LT) recipients because of the potential rapid development and dissemination of the disease. Depending on the pathophysiology, CI may manifest with a wide range of clinical presentations that may delay early diagnosis and timely treatment. Additionally, most anticryptococcal therapies may threaten LT recipients owing to the associated hepatotoxicity of these medications. We report a case of a 25-year-old woman who received an LT for cryptogenic cirrhosis and developed rapidly progressive CI with pulmonary, myocardial, and cerebral involvement within a month of transplantation. She presented with severe pulmonary hypertension refractory to medical management and subsequently died despite our efforts. Herein, we review the etiology of cryptococcosis, the natural history of cryptococcal disease, and standard treatments for CI, and we highlight peculiarities of Cryptococcus neoformans infection in solid organ transplant recipients.


Assuntos
Criptococose/etiologia , Transplante de Fígado/efeitos adversos , Complicações Pós-Operatórias/microbiologia , Adulto , Criptococose/mortalidade , Cryptococcus neoformans , Evolução Fatal , Feminino , Humanos , Complicações Pós-Operatórias/mortalidade
19.
IDCases ; 19: e00692, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31993322

RESUMO

Histoplasma capsulatum is typically an indolent disease among immunocompetent patients. However, immunocompromised patients, such as solid organ transplant recipients, are at risk of developing severe histoplasmosis. Yet post-transplant histoplasmosis is a rare pathology, representing less than five percent of invasive fungal infections among transplant recipients. Furthermore, patients tend to present with nonspecific clinical symptoms, complicating timely diagnosis and delaying treatment. Disease features that may be more representative of H. capsulatum infection, such as anemia, leukopenia and pulmonary involvement are often not present until late in the disease course, when the patient is at greater risk of decompensation. Unlike H. capsulatum infections among immunocompetent hosts, extrapulmonary infection among immunocompromised hosts is more the rule than the exception. Treatment with liposomal amphotericin B followed by oral itraconazole is the standard therapy, but special considerations must be made for patients with hepatic and/or renal insufficiency, underlying cardiac abnormalities or malabsorptive pathologies and doses of immunosuppressants will need to be adjusted for drug interactions. Herein we present a case of H. capsulatum infection presenting with generalized lymphadenopathy post-renal transplant.

20.
Toxins (Basel) ; 12(10)2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33023159

RESUMO

Venomous snakes are important subjects of study in evolution, ecology, and biomedicine. Many venomous snakes have alpha-neurotoxins (α-neurotoxins) in their venom. These toxins bind the alpha-1 nicotinic acetylcholine receptor (nAChR) at the neuromuscular junction, causing paralysis and asphyxia. Several venomous snakes and their predators have evolved resistance to α-neurotoxins. The resistance is conferred by steric hindrance from N-glycosylated asparagines at amino acids 187 or 189, by an arginine at position 187 that has been hypothesized to either electrostatically repulse positively charged neurotoxins or sterically interfere with α-neurotoxin binding, or proline replacements at positions 194 or 197 of the nAChR ligand-binding domain to inhibit α-neurotoxin binding through structural changes in the receptor. Here, we analyzed this domain in 148 vertebrate species, and assessed its amino acid sequences for resistance-associated mutations. Of these sequences, 89 were sequenced de novo. We find widespread convergent evolution of the N-glycosylation form of resistance in several taxa including venomous snakes and their lizard prey, but not in the snake-eating birds studied. We also document new lineages with the arginine form of inhibition. Using an in vivo assay in four species, we provide further evidence that N-glycosylation mutations reduce the toxicity of cobra venom. The nAChR is of crucial importance for normal neuromuscular function and is highly conserved throughout the vertebrates as a result. Our research shows that the evolution of α-neurotoxins in snakes may well have prompted arms races and mutations to this ancient receptor across a wide range of sympatric vertebrates. These findings underscore the inter-connectedness of the biosphere and the ripple effects that one adaption can have across global ecosystems.


Assuntos
Resistência a Medicamentos , Evolução Molecular , Junção Neuromuscular/efeitos dos fármacos , Neurotoxinas/toxicidade , Antagonistas Nicotínicos/toxicidade , Receptores Nicotínicos/efeitos dos fármacos , Mordeduras de Serpentes/metabolismo , Venenos de Serpentes/toxicidade , Serpentes/metabolismo , Animais , Sítios de Ligação , Resistência a Medicamentos/genética , Glicosilação , Mutação , Junção Neuromuscular/metabolismo , Junção Neuromuscular/fisiopatologia , Neurotoxinas/metabolismo , Antagonistas Nicotínicos/metabolismo , Filogenia , Ligação Proteica , Receptores Nicotínicos/genética , Receptores Nicotínicos/metabolismo , Mordeduras de Serpentes/fisiopatologia , Venenos de Serpentes/metabolismo , Especificidade da Espécie
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