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1.
J Med Virol ; 91(7): 1250-1262, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30815882

RESUMEN

The role of human adenovirus (HAdV) infection in different acute diseases, such as febrile exudative tonsillitis, conjunctivitis, and pharyngoconjunctival fever is well established. However, the relationships, if any, of HAdV persistence and reactivation in the development of the chronic adenotonsillar disease is not fully understood. The present paper reports a 3-year cross-sectional hospital-based study aimed at detecting and quantifying HAdV DNA and mRNA of the HAdV hexon gene in adenoid and palatine tonsil tissues and nasopharyngeal secretions (NPS) from patients with adenotonsillar hypertrophy or recurrent adenotonsillitis. HAdV C, B, and E were detectable in nearly 50% of the patients, with no association with the severity of airway obstruction, nor with the presence of recurrent tonsillitis, sleep apnea or otitis media with effusion (OME). Despite the higher rates of respiratory viral coinfections in patients with HAdV, the presence of other viruses, including DNA and RNA viruses, had no association with HAdV replication or shedding in secretions. Higher HAdV loads in adenoids showed a significant positive correlation with the presence of sleep apnea and the absence of OME. Although this study indicates that a significant proportion (~85%) of individuals with chronic adenotonsillar diseases have persistent nonproductive HAdV infection, including those by HAdV C, B, and E, epithelial and subepithelial cells in tonsils seem to be critical for HAdV C production and shedding in NPS in some patients, since viral antigen was detected in these regions by immunohistochemistry in four patients, all of which were also positive for HAdV mRNA detection.


Asunto(s)
Tonsila Faríngea/virología , Infecciones por Adenovirus Humanos/virología , Tonsila Palatina/virología , Replicación Viral , Tonsila Faríngea/patología , Infecciones por Adenovirus Humanos/diagnóstico , Adenovirus Humanos/clasificación , Adenovirus Humanos/aislamiento & purificación , Adenovirus Humanos/fisiología , Adolescente , Niño , Preescolar , Estudios Transversales , ADN Viral/aislamiento & purificación , Femenino , Humanos , Hipertrofia , Lactante , Masculino , Tonsila Palatina/patología , Tonsilitis/virología
2.
J Infect Dis ; 220(2): 203-212, 2019 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-30901054

RESUMEN

BACKGROUND: Zika virus (ZIKV) infections have reemerged as a global health issue due to serious clinical complications. Development of specific serological assays to detect and differentiate ZIKV from other cocirculating flaviviruses for accurate diagnosis remains a challenge. METHODS: We investigated antibody responses in 51 acute ZIKV-infected adult patients from Campinas, Brazil, including 7 pregnant women who later delivered during the study. Using enzyme-linked immunosorbent assays, levels of antibody response were measured and specific epitopes identified. RESULTS: Several antibody-binding hot spots were identified in ZIKV immunogenic antigens, including membrane, envelope (E) and nonstructural protein 1 (NS1). Interestingly, specific epitopes (2 from E and 2 from NS1) strongly recognized by ZIKV-infected patients' antibodies were identified and were not cross-recognized by dengue virus (DENV)-infected patients' antibodies. Corresponding DENV peptides were not strongly recognized by ZIKV-infected patients' antibodies. Notably, ZIKV-infected pregnant women had specific epitope recognition for ZIKV NS1 (amino acid residues 17-34), which could be a potential serological marker for early ZIKV detection. CONCLUSIONS: This study identified 6 linear ZIKV-specific epitopes for early detection of ZIKV infections. We observed differential epitope recognition between ZIKV-infected and DENV-infected patients. This information will be useful for developing diagnostic methods that differentiate between closely related flaviviruses.


Asunto(s)
Epítopos/inmunología , Proteínas no Estructurales Virales/inmunología , Infección por el Virus Zika/inmunología , Virus Zika/inmunología , Enfermedad Aguda , Adolescente , Adulto , Anciano , Anticuerpos Monoclonales/inmunología , Anticuerpos Antivirales/inmunología , Formación de Anticuerpos/inmunología , Brasil , Reacciones Cruzadas/inmunología , Dengue/inmunología , Dengue/virología , Virus del Dengue/inmunología , Ensayo de Inmunoadsorción Enzimática/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas Serológicas , Adulto Joven , Infección por el Virus Zika/virología
3.
Genome Announc ; 6(27)2018 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-29976603

RESUMEN

Draft genomes of three Salmonella enterica 4,[5],12:i:- (STi) strains isolated from human infections were obtained using Illumina sequencing. They were negative for the fljBA operon but positive for hin, and k-mer analyses revealed their identity as S. enterica 4,[5],12:i:- 08-1736 and S Typhimurium. A draft S Typhimurium sequence is described for comparison.

4.
Artículo en Inglés | MEDLINE | ID: mdl-29696139

RESUMEN

Recent Zika outbreaks in South America, accompanied by unexpectedly severe clinical complications have brought much interest in fast and reliable screening methods for ZIKV (Zika virus) identification. Reverse-transcriptase polymerase chain reaction (RT-PCR) is currently the method of choice to detect ZIKV in biological samples. This approach, nonetheless, demands a considerable amount of time and resources such as kits and reagents that, in endemic areas, may result in a substantial financial burden over affected individuals and health services veering away from RT-PCR analysis. This study presents a powerful combination of high-resolution mass spectrometry and a machine-learning prediction model for data analysis to assess the existence of ZIKV infection across a series of patients that bear similar symptomatic conditions, but not necessarily are infected with the disease. By using mass spectrometric data that are inputted with the developed decision-making algorithm, we were able to provide a set of features that work as a "fingerprint" for this specific pathophysiological condition, even after the acute phase of infection. Since both mass spectrometry and machine learning approaches are well-established and have largely utilized tools within their respective fields, this combination of methods emerges as a distinct alternative for clinical applications, providing a diagnostic screening-faster and more accurate-with improved cost-effectiveness when compared to existing technologies.

5.
Sci Rep ; 8(1): 4012, 2018 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-29507368

RESUMEN

Infection with Zika virus (ZIKV), a mosquito-borne flavivirus has been casually linked with increased congenital microcephaly in Brazil from 2015 through 2016. Sensitive and specific diagnosis of patients with Zika fever (ZIKF) remains critical for patient management. We developed a ZIKV NS5 qRT-PCR assay by combining primers described by Balm et al. and a new Taqman probe. The assay was evaluated and compared with another assay described by Lanciotti et al. (ZIKV 1107) using 51 blood and 42 urine samples from 54 suspected ZIKV patients. ZIKV NS5 performed better in terms of sensitivity with more samples detected as ZIKV-positive (n = 37) than ZIKV 1107 (n = 34) for urine, and ZIKV-positive (n = 29) than ZIKV 1107 (n = 26) for blood. Both assays displayed good overall agreement for urine (κappa = 0.770) and blood (κappa = 0.825) samples. Improved availability of validated diagnostic tests, such ZIKV NS5 qRT-PCR, will be critical to ensure adequate and accurate ZIKV diagnosis.


Asunto(s)
Brotes de Enfermedades , ARN Viral/sangre , Infección por el Virus Zika/epidemiología , Virus Zika/genética , Adulto , Brasil/epidemiología , Femenino , Humanos , Límite de Detección , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Adulto Joven , Infección por el Virus Zika/diagnóstico , Infección por el Virus Zika/virología
6.
Microbes Infect ; 20(11-12): 661-669, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-29501560

RESUMEN

Zika virus (ZIKV) greatly impacted the international scientific and public health communities in the last two years due to its association with microcephaly and other neonatal alterations. This review will discuss lessons learned from viral pathogenesis, epidemiology and clinical findings observed during the ZIKV outbreak occurred between 2014 and 2016 in Brazil.


Asunto(s)
Brotes de Enfermedades , Infección por el Virus Zika/epidemiología , Infección por el Virus Zika/virología , Virus Zika/patogenicidad , Brasil/epidemiología , Femenino , Humanos , Microcefalia/epidemiología , Microcefalia/etiología , Microcefalia/virología , Placenta/virología , Embarazo , Tropismo Viral , Virus Zika/fisiología , Infección por el Virus Zika/complicaciones , Infección por el Virus Zika/transmisión
7.
Pathog Dis ; 75(6)2017 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-28859308

RESUMEN

Salmonella enterica Enteritidis forms biofilms and survives in agricultural environments, infecting poultry and eggs. Bacteria in biofilms are difficult to eradicate compared to planktonic cells, causing serious problems in industry and public health. In this study, we evaluated the role of ihfA and ihfB in biofilm formation by S. enterica Enteritidis by employing different microbiology techniques. Our data indicate that ihf mutant strains are impaired in biofilm formation, showing a reduction in matrix formation and a decrease in viability and metabolic activity. Phenotypic analysis also showed that deletion of ihf causes a deficiency in curli fimbriae expression, cellulose production and pellicle formation. These results show that integration host factor has an important regulatory role in biofilm formation by S. enterica Enteritidis.


Asunto(s)
Biopelículas/crecimiento & desarrollo , Fimbrias Bacterianas/genética , Regulación Bacteriana de la Expresión Génica , Factores de Integración del Huésped/genética , Plancton/genética , Salmonella enteritidis/genética , Celulosa/biosíntesis , Fimbrias Bacterianas/metabolismo , Eliminación de Gen , Aptitud Genética , Factores de Integración del Huésped/deficiencia , Plancton/crecimiento & desarrollo , Plancton/metabolismo , Polisacáridos Bacterianos/biosíntesis , Polisacáridos Bacterianos/deficiencia , Subunidades de Proteína/deficiencia , Subunidades de Proteína/genética , Salmonella enteritidis/crecimiento & desarrollo , Salmonella enteritidis/metabolismo , Salmonella enteritidis/patogenicidad
8.
Pathog. Dis. ; 75(6)2017.
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib15097

RESUMEN

Salmonella enterica Enteritidis forms biofilms and survives in agricultural environments, infecting poultry and eggs. Bacteria in biofilms are difficult to eradicate compared to planktonic cells, causing serious problems in industry and public health. In this study, we evaluated the role of ihfA and ihfB in biofilm formation by S. enterica Enteritidis by employing different microbiology techniques. Our data indicate that ihf mutant strains are impaired in biofilm formation, showing a reduction in matrix formation and a decrease in viability and metabolic activity. Phenotypic analysis also showed that deletion of ihf causes a deficiency in curli fimbriae expression, cellulose production and pellicle formation. These results show that integration host factor has an important regulatory role in biofilm formation by S. enterica Enteritidis.

9.
PLoS One ; 11(10): e0164377, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27723844

RESUMEN

Recent outbreaks of Zika virus in Oceania and Latin America, accompanied by unexpected clinical complications, made this infection a global public health concern. This virus has tropism to neural tissue, leading to microcephaly in newborns in a significant proportion of infected mothers. The clinical relevance of this infection, the difficulty to perform accurate diagnosis and the small amount of data in literature indicate the necessity of studies on Zika infection in order to characterize new biomarkers of this infection and to establish new targets for viral control in vertebrates and invertebrate vectors. Thus, this study aims at establishing a lipidomics profile of infected mosquito cells compared to a control group to define potential targets for viral control in mosquitoes. Thirteen lipids were elected as specific markers for Zika virus infection (Brazilian strain), which were identified as putatively linked to the intracellular mechanism of viral replication and/or cell recognition. Our findings bring biochemical information that may translate into useful targets for breaking the transmission cycle.


Asunto(s)
Aedes/metabolismo , Aedes/virología , Metabolismo de los Lípidos , Infección por el Virus Zika/metabolismo , Virus Zika/metabolismo , Animales , Línea Celular , Femenino , Humanos , América Latina/epidemiología , Masculino , Oceanía/epidemiología , Infección por el Virus Zika/epidemiología , Infección por el Virus Zika/transmisión
10.
Braz. j. microbiol ; 47(2): 414-416, Apr.-June 2016. graf
Artículo en Inglés | LILACS | ID: lil-780834

RESUMEN

Abstract Escherichia coli is the major causative agent of human cystitis. In this study, a preliminary molecular analysis carried out by PCR (polymerase chain reaction) demonstrated that 100% of 31 E. coli strains isolated from patients with recurrent UTIs (urinary tract infections) showed the presence of the curli fimbria gene (csgA). Curli fimbria is known to be associated with bacterial biofilm formation but not with the adhesion of human cystitis-associated E. coli. Therefore, this work aimed to study how curli fimbria is associated with uropathogenic E. coli (UPEC) as an adhesion factor. For this purpose, the csgA gene was deleted from strain UPEC-4, which carries three adhesion factor genes (csgA, fimH and ompA). The wild-type UPEC-4 strain and its mutant (ΔcsgA) were analyzed for their adhesion ability over HTB-9 (human bladder carcinoma), Vero (kidney cells of African green monkey) and HUVEC (human umbilical vein) cells in the presence of α-D-mannose. All the wild-type UPEC strains tested (100%) were able to adhere to all three cell types, while the UPEC-4 ΔcsgA mutant lost its adherence to HTB-9 but continued to adhere to the HUVEC and Vero cells. The results suggest that curli fimbria has an important role in the adhesion processes associated with human UPEC-induced cystitis.


Asunto(s)
Humanos , Adhesinas de Escherichia coli/metabolismo , Cistitis/microbiología , Proteínas de Escherichia coli/metabolismo , Infecciones por Escherichia coli/microbiología , Escherichia coli Uropatógena/metabolismo , Adhesión Bacteriana , Regulación Bacteriana de la Expresión Génica , Eliminación de Secuencia , Adhesinas de Escherichia coli/genética , Proteínas de Escherichia coli/genética , Escherichia coli Uropatógena/genética
11.
Genome Announc ; 4(3)2016 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-27174265

RESUMEN

The draft genome of Salmonella enterica serovar Enteritidis phage type 4 (PT4) strain IOC4647/2004, isolated from a poultry farm in São Paulo state, was obtained with high-throughput Illumina sequencing platform, generating 4,173,826 paired-end reads with 251 bp. The assembly of 4,804,382 bp in 27 scaffolds shows strong similarity to other S Enteritidis strains.

12.
Braz J Microbiol ; 47(2): 414-6, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26991275

RESUMEN

Escherichia coli is the major causative agent of human cystitis. In this study, a preliminary molecular analysis carried out by PCR (polymerase chain reaction) demonstrated that 100% of 31 E. coli strains isolated from patients with recurrent UTIs (urinary tract infections) showed the presence of the curli fimbria gene (csgA). Curli fimbria is known to be associated with bacterial biofilm formation but not with the adhesion of human cystitis-associated E. coli. Therefore, this work aimed to study how curli fimbria is associated with uropathogenic E. coli (UPEC) as an adhesion factor. For this purpose, the csgA gene was deleted from strain UPEC-4, which carries three adhesion factor genes (csgA, fimH and ompA). The wild-type UPEC-4 strain and its mutant (ΔcsgA) were analyzed for their adhesion ability over HTB-9 (human bladder carcinoma), Vero (kidney cells of African green monkey) and HUVEC (human umbilical vein) cells in the presence of α-d-mannose. All the wild-type UPEC strains tested (100%) were able to adhere to all three cell types, while the UPEC-4 ΔcsgA mutant lost its adherence to HTB-9 but continued to adhere to the HUVEC and Vero cells. The results suggest that curli fimbria has an important role in the adhesion processes associated with human UPEC-induced cystitis.


Asunto(s)
Adhesinas de Escherichia coli/metabolismo , Cistitis/microbiología , Infecciones por Escherichia coli/microbiología , Proteínas de Escherichia coli/metabolismo , Escherichia coli Uropatógena/metabolismo , Adhesinas de Escherichia coli/genética , Adhesión Bacteriana , Proteínas de Escherichia coli/genética , Regulación Bacteriana de la Expresión Génica , Humanos , Eliminación de Secuencia , Escherichia coli Uropatógena/genética
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