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1.
Viruses ; 12(1)2020 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31947825

RESUMO

Zika virus (ZIKV) emerged in the Americas in 2015, presenting unique challenges to public health. Unlike other arboviruses of the Flaviviridae family, it is transmissible by sexual contact, which facilitates the spread of the virus into new geographic areas. Additionally, ZIKV can be transmitted from mother to fetus, causing microcephaly and other severe developmental abnormalities. Reliable and easy-to-work-with clones of ZIKV expressing heterologous genes will significantly facilitate studies aimed at understanding the virus pathogenesis and tissue tropism. Here, we developed and characterized two novel approaches for expression of heterologous genes of interest in the context of full-length ZIKV genome and compared them to two previously published strategies for ZIKV-mediated gene expression. We demonstrated that among the four tested viruses expressing nLuc gene, the virus constructed using a newly developed approach of partial capsid gene duplication (PCGD) attained the highest titer in Vero cells and resulted in the highest level of nLuc expression. Suitability of the PCGD approach for expression of different genes of interest was validated by replacing nLuc sequence with that of eGFP gene. The generated constructs were further characterized in cell culture. Potential applications of ZIKV clones stably expressing heterologous genes include development of detection assays, antivirals, therapeutics, live imaging systems, and vaccines.

2.
Eur Neurol ; : 1-8, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31968331

RESUMO

BACKGROUND: In 1947, Zika virus (ZIKV) was first discovered in Monkeys, in Zika Forest, in Uganda, Africa. Five years later, (1952) the first human Zika infection was detected in Nigeria, Africa. After this date, only sporadic cases happened, until the first 3 epidemics occurred, all outside Africa. The first epidemic was in Yap Island in 2007, the second in French Polynesia in 2013, and the third in 2015 in the northeast of Brazil, and then the spread to the Americas in 2015 and 2016. However, it was only after the epidemic in the northeast of Brazil, in the first half of 2015, that many babies were born with microcephaly in the second semester of that same year and in 2016. Until now, every year, some babies are still born with congenital ZIKV syndrome (CZVS). SUMMARY: The objective of this article is to describe infrequent and rarely discussed imaging (computed tomography and magnetic resonance imaging) findings of CZVS, in addition to those classically described such as a simplified gyral pattern, ventriculomegaly, corpus callosum dysgenesis, craniofacial disproportion, and redundant scalp, thus suggesting an increase in the spectrum of neurological findings related to the syndrome.

3.
J Biomol Struct Dyn ; : 1-13, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31920173

RESUMO

Zika virus (ZIKV), belongs to the flavivirus genus and Flaviviridae family that associated with serious diseased conditions like microcephaly and other neurological disorders (Guillan-Barré syndrome). As there is no vaccine or therapies available against ZIKV to date. Hence, it is an unmet need to find potential drug candidates and target sites against Zika virus infection. NS2B-NS3 protease making an attractive target for therapeutic intervention in ZIKV infections because of its critical role in hydrolysis of a single polyprotein encoded by Zika virus. Recently, there are some experimental evidence about the flavonoids as Zika virus NS2B-NS3 protease inhibitors. However, molecular interaction between protease complex and inhibitors at atomic levels has not been explored. Here, we have taken the experimentally validated thirty-eight flavonoids inhibitors against NS2B-NS3 protease to examine the molecular interaction using molecular docking and molecular dynamics simulations. We found out few flavonoids such as EGCG and its two derivatives, isoquercetin, rutin and sanggenon O showing interaction with catalytic triad (His51, Asp75, and Ser135) of the active site of NS2B-NS3 protease and found to be stable throughout the simulation. Therefore it is evident that interaction with the catalytic triad playing a vital role in the inhibition of the enzyme activity as a result inhibition of the virus propagation. However these compounds can be explored further for understanding the mechanism of action of these compounds targeting NS2B-NS3 protease for inhibition of Zika virus.

4.
Am J Trop Med Hyg ; 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31933455

RESUMO

During the 2016 Zika pandemic in Brazil, women's perceptions of infection risk, ability to adhere to Zika prevention strategies, or access to services following exposure were not emphasized in the public health response. Women in Fortaleza, Brazil, responded to a questionnaire on social factors related to perceived Zika risk and access to health care in June 2016. Data were coded using prespecified categories, and response frequency was reported. Of 37 respondents, most reported a lack of public services to support mosquito control (n = 19) or delayed access to reproductive health care (n = 14). Only 22% described specific maternal risks or fetal outcomes as a consequence of Zika infection. Respondents indicated an overall disconnect between public health efforts and women's perceptions of their reproductive control, including limited support concerning microcephaly in infants. Interventions targeting Zika may require a greater emphasis on strengthening health systems and infrastructure to realistically prevent transmission.

5.
Viruses ; 12(1)2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31936159

RESUMO

In 2015 Zika virus (ZIKV) emerged for the first time in South America. The following ZIKV epidemic resulted in the appearance of a clinical phenotype with microcephaly and other severe malformations in newborns. So far, mechanisms of ZIKV induced damage to the fetus are not completely understood. Previous data suggest that ZIKV may bypass the placenta to reach the fetus. Thus, animal models for ZIKV infection are important to facilitate studies about ZIKV infection during pregnancy. Here, we used ultrasound based imaging (USI) to characterize ZIKV induced pathogenesis in the pregnant Type I interferon receptor-deficient (IFNAR-/-) mouse model. Based on USI we suggest the placenta to be a primary target organ of ZIKV infection enabling ZIKV spreading to the fetus. Moreover, in addition to direct infection of the fetus, the placental ZIKV infection may cause an indirect damage to the fetus through reduced uteroplacental perfusion leading to intrauterine growth retardation (IUGR) and fetal complications as early as embryonic day (ED) 12.5. Our data confirmed the capability of USI to characterize ZIKV induced modifications in mouse fetuses. Data from further studies using USI to monitor ZIKV infections will contribute to a better understanding of ZIKV infection in pregnant IFNAR-/- mice.

6.
Cells ; 9(1)2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31936331

RESUMO

The Zika virus (ZIKV) is a mosquito-borne Flavivirus and can be transmitted through an infected mosquito bite or through human-to-human interaction by sexual activity, blood transfusion, breastfeeding, or perinatal exposure. After the 2015-2016 outbreak in Brazil, a strong link between ZIKV infection and microcephaly emerged. ZIKV specifically targets human neural progenitor cells, suggesting that proteins encoded by ZIKV bind and inactivate host cell proteins, leading to microcephaly. Here, we present a systematic annotation of interactions between human proteins and the seven non-structural ZIKV proteins corresponding to a Brazilian isolate. The interaction network was generated by combining tandem-affinity purification followed by mass spectrometry with yeast two-hybrid screens. We identified 150 human proteins, involved in distinct biological processes, as interactors to ZIKV non-structural proteins. Our interacting network is composed of proteins that have been previously associated with microcephaly in human genetic disorders and/or animal models. Further, we show that the protein inhibitor of activated STAT1 (PIAS1) interacts with NS5 and modulates its stability. This study builds on previously published interacting networks of ZIKV and genes related to autosomal recessive primary microcephaly to generate a catalog of human cellular targets of ZIKV proteins implicated in processes related to microcephaly in humans. Collectively, these data can be used as a resource for future characterization of ZIKV infection biology and help create a basis for the discovery of drugs that may disrupt the interaction and reduce the health damage to the fetus.

7.
Infect Genet Evol ; 80: 104180, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31918041

RESUMO

Zika virus (ZIKV) is a negative sense RNA virus from the Flaviviridae family, which was relatively unknown until the first human epidemic in Micronesia, in 2007. Since then, it spread to French Polynesia and the Americas. Recife, the capital of Pernambuco state and epicenter of the Zika epidemic in Brazil, experienced a large number of microcephaly cases and other congenital abnormalities associated to the ZIKV infection from, 2015 to 16. Evidences suggest that both Aedes aegypti and Culex quinquefasciatus mosquitoes from Recife are capable of replicating and transmitting the virus. Here, we conducted high throughput sequencing of ZIKV genomes directly from Ae. aegypti and Cx. quinquefasciatus mosquitoes collected during the ZIKV epidemics in Recife, in order to investigate the variability and evolution of the virus. We obtained 11 draft ZIKV genomes derived from 5 pools from each Ae. aegypti and Cx. quinquefasciatus species. Genome coverage breadth ranged from 16 to 100% and average depth from 45 to 46,584×. Two of these genomes were obtained from pools of Cx. quinquefasciatus females with no sign of blood in the abdomen. Amino acid substitutions found here were not species-specific. In addition, molecular clock dating estimated that ZIKV draft genomes obtained here were co-circulating in other regions of the country during the epidemics. Overall results highlight that viral mutations and even minor variants can be detected in genomes directly sequenced from mosquito samples and insights about natural viral genomic variability and viral evolution can be useful when designing tools for mosquito control programs.

8.
Artigo em Inglês | MEDLINE | ID: mdl-31973162

RESUMO

Since an outbreak in Brazil, which started in 2015, Zika has been recognized as an important cause of microcephaly. The highest burden of this outbreak was in northeast Brazil, including the state of Pernambuco. The prevalence of congenital microcephaly in Pernambuco state was estimated from the RESP (Registro de Eventos em Saúde Pública) surveillance system, from August 2015 to August 2016 inclusive. The denominators were estimated at the municipality level from official demographic data. Microcephaly was defined as a neonatal head circumference below the 3rd percentile of the Intergrowth standards. Smoothed maps of the prevalence of microcephaly were obtained from a Bayesian model which was conditional autoregressive (CAR) in space, and first order autoregressive in time. A total of 742 cases were identified. Additionally, high and early occurrences were identified in the Recife Metropolitan Region, on the coast, and in a north-south band about 300 km inland. Over a substantial part of the state, the overall prevalence, aggregating over the study period, was above 0.5%. The reasons for the high occurrence in the inland area remain unclear.

9.
Neuroradiol J ; : 1971400919896264, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31896285

RESUMO

BACKGROUND: Many original articles and case series have been published emphasizing the neuroimaging findings of congenital Zika virus (ZIKV) infection. The majority of these studies do not follow a neuroradiological methodology to describe malformations and brain abnormalities resulting from ZIKV infection. The cause-and-effect correlation between the gestational period of maternal infection and the severity of encephalic changes at birth has rarely been reported. A systematic literature review was conducted on the neuroimaging findings in children affected with microcephaly due to ZIKV. METHODS: PubMed, Cochrane Library and Web of Science were searched for full-text articles published up to July 2019. Duplicate entries were removed. Two independent reviewers performed a quality assessment of all the studies included. RESULTS: A total of 2214 publications were identified. Of these 2170 were excluded by analysis of titles and abstracts, resulting in the inclusion of only eight articles. Chi-square and Fisher's exact tests were performed with a 95% confidence interval to verify the statistically significant differences in the neuroradiological findings between the cases of ZIKV infection in the first or second trimester of gestation. The studies published so far have described image abnormalities at random, without utilizing any pre-established neuroradiological criteria, and imaging modalities with different sensitivity and accuracy have been used, which jeopardizes a reliable and adequate statistical analysis. CONCLUSIONS: Neuroimaging abnormalities are much more prevalent and severe when the infection by ZIKV is contracted in the first or second trimester of pregnancy.

10.
Sci Adv ; 6(2): eaaw6284, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31950075

RESUMO

Zika virus (ZIKV) infection during pregnancy is associated with a spectrum of developmental impairments known as congenital Zika syndrome (CZS). The prevalence of this syndrome varies across ZIKV endemic regions, suggesting that its occurrence could depend on cofactors. Here, we evaluate the relevance of protein malnutrition for the emergence of CZS. Epidemiological data from the ZIKV outbreak in the Americas suggest a relationship between undernutrition and cases of microcephaly. To experimentally examine this relationship, we use immunocompetent pregnant mice, which were subjected to protein malnutrition and infected with a Brazilian ZIKV strain. We found that the combination of protein restriction and ZIKV infection leads to severe alterations of placental structure and embryonic body growth, with offspring displaying a reduction in neurogenesis and postnatal brain size. RNA-seq analysis reveals gene expression deregulation required for brain development in infected low-protein progeny. These results suggest that maternal protein malnutrition increases susceptibility to CZS.

11.
Am J Obstet Gynecol ; 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31954155

RESUMO

BACKGROUND: Zika virus (ZIKV) infection during pregnancy can cause serious birth defects, including brain and eye abnormalities. The clinical importance of detection of ZIKV ribonucleic acid (RNA) in amniotic fluid is unknown. OBJECTIVES: To describe patterns of ZIKV RNA testing of amniotic fluid relative to other clinical specimens and to examine the association between ZIKV detection in amniotic fluid and Zika-associated birth defects. Our null hypothesis was that ZIKV detection in amniotic fluid was not associated with Zika-associated birth defects. STUDY DESIGN: We conducted a retrospective cohort analysis of women with amniotic fluid specimens submitted to Colombia's National Institute of Health as part of national ZIKV surveillance from January 2016 to January 2017. Specimens (maternal serum, amniotic fluid, cord blood, umbilical cord tissue, and placental tissue) were tested for the presence of ZIKV RNA using a singleplex or multiplex real-time reverse transcriptase-polymerase chain reaction (rRT-PCR) assay. Birth defect information was abstracted from maternal prenatal and infant birth records and reviewed by expert clinicians. Chi-square and Fisher's exact tests were used to compare the frequency of Zika-associated birth defects (defined as brain abnormalities [with or without microcephaly, but excluding neural tube defects and their associated findings] or eye abnormalities) by frequency of detection of ZIKV RNA in amniotic fluid. RESULTS: Our analysis included 128 women with amniotic fluid specimens. Seventy-five women (58%) had prenatally-collected amniotic fluid, 42 (33%) at delivery, and 11 (9%) had missing collection dates. Ninety-one women had both amniotic fluid and other clinical specimens submitted for testing, allowing for comparison across specimen types. Of those 91 women, 68 had evidence of ZIKV infection based on detection of ZIKV RNA (ZIKV+) in >1 specimen. Testing of amniotic fluid collected prenatally or at delivery identified 39 (57%) of these ZIKV infections (15 [22%] identified only in amniotic fluid), and 29 (43%) infections were identified in other specimen types and not amniotic fluid. Among women included in the analysis, 89 had pregnancy outcome information available, allowing for assessment of the presence of Zika-associated birth defects. Zika-associated birth defects were significantly (p<0.05) more common among pregnancies with ZIKV+ amniotic fluid specimens collected prenatally (19/32, 59%) than for those with no laboratory evidence of ZIKV infection in any specimen (6/23, 26%), but the proportion was similar in pregnancies with only ZIKV+ specimens other than amniotic fluid (10/23, 43%). Though Zika-associated birth defects were more common among women with any ZIKV+ amniotic fluid specimen (i.e., collected prenatally or at delivery; 21/43, 49%) than those with no laboratory evidence of ZIKV infection (6/23, 26%), this comparison did not reach statistical significance (p=0.07). CONCLUSIONS: Testing of amniotic fluid provided additional evidence for maternal diagnosis of ZIKV infection. Zika-associated birth defects were more common among women with ZIKV RNA detected in prenatal amniotic fluid specimens than women with no laboratory evidence of ZIKV infection, but similar to women with ZIKV RNA detected in other, non-amniotic fluid specimen types.

12.
Int J Gynaecol Obstet ; 148 Suppl 2: 9-14, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31975394

RESUMO

OBJECTIVE: To identify newborns with congenital Zika infection (CZI) at a maternity hospital in Salvador, Brazil, during the 2016 microcephaly outbreak. METHODS: A prospective study enrolled microcephalic and normocephalic newborns with suspected CZI between January and December 2016. Serology (immunoglobulins IgM and IgG) and quantitative reverse transcriptase polymerase chain reaction (RT-qPCR) for the Zika virus were performed. Demographic and clinical characteristics of newborns with and without microcephaly were compared. RESULTS: Of the 151 newborns enrolled, 32 (21.2%) were classified as microcephalic. The majority of these cases were born between January and May 2016. IgM and IgG Zika virus antibodies were detected in 5 (23.8%) and 17 (80.9%) microcephalic newborn blood samples, respectively. Six (24%) microcephalic newborns tested positive for Zika virus by RT-qPCR in urine or placenta samples. Thirteen (11.8%) normocephalic newborns also tested positive for Zika virus by PCR in urine, plasma, or placenta samples, while IgM antibodies against Zika were detected in 4 (4.2%) others. CONCLUSIONS: Identification of 17 normocephalic CZI cases, confirmed by IgM serology or RT-qPCR for Zika virus, provides evidence that CZI can present asymptomatically at birth. This finding highlights the need for prenatal and neonatal screening for Zika virus in endemic regions.

13.
Int J Gynaecol Obstet ; 148 Suppl 2: 29-35, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31975397

RESUMO

OBJECTIVE: To explore the perceptions and experiences of pregnant women in accessing healthcare services during the epidemic in Colombia during 2015-2016. METHODS: A qualitative study using semistructured interviews was conducted in Villavicencio. Six women who had been diagnosed with Zika virus infection during their pregnancies and whose fetus had suspected microcephaly participated in the investigation. Grounded theory was used and thematic content analysis was made for each category identified. RESULTS: Three main themes affecting access to healthcare services were identified: (1) women knew basic information about the virus, but it was limited; (2) access to services was delayed due to their lack of availability or limited supply in the municipality; and (3) most of the participants made out-of-pocket payments to get access to services that were not provided. CONCLUSIONS: Several gaps were identified in the provision of healthcare services to pregnant women during the Zika epidemic. Policy makers need to utilize the results from affected communities to develop and implement public policies that adapt and respond to their priorities and needs.

14.
Int J Gynaecol Obstet ; 148 Suppl 2: 20-28, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31975400

RESUMO

OBJECTIVE: To describe the repercussions, from the perspectives of caregiver mothers, of confirmed congenital Zika syndrome (CZS) in their offspring. METHODS: A descriptive-exploratory study with a qualitative approach was carried out in the state of Espírito Santo in southeastern Brazil, with 25 women who had a child diagnosed with CZS. RESULTS: Emerging themes from the content analysis were grouped into two categories: (1) inequalities experienced by mothers, including social inequality, poverty, and gender inequality; (2) the impact of a child with CZS on mothering, including feelings at the time of diagnosis, maternal isolation and mental health, experiences of stigma and prejudice, and exhausting itineraries searching for therapeutic care. CONCLUSION: The repercussions of CZS were a huge burden on already vulnerable women, and social inequalities and poverty were important markers in the mothers' reports. Many of the families affected by CZS already lived in precarious social conditions and these conditions were exacerbated further. Robust public and social policies to support these mothers need effective implementation given that babies born with CZS need long-term care and support.

15.
PLoS One ; 14(12): e0225699, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31809512

RESUMO

The question of how Zika virus (ZIKV) changed from a seemingly mild virus to a human pathogen capable of microcephaly and sexual transmission remains unanswered. The unexpected emergence of ZIKV's pathogenicity and capacity for sexual transmission may be due to genetic changes, and future changes in phenotype may continue to occur as the virus expands its geographic range. Alternatively, the sheer size of the 2015-16 epidemic may have brought attention to a pre-existing virulent ZIKV phenotype in a highly susceptible population. Thus, it is important to identify patterns of genetic change that may yield a better understanding of ZIKV emergence and evolution. However, because ZIKV has an RNA genome and a polymerase incapable of proofreading, it undergoes rapid mutation which makes it difficult to identify combinations of mutations associated with viral emergence. As next generation sequencing technology has allowed whole genome consensus and variant sequence data to be generated for numerous virus samples, the task of analyzing these genomes for patterns of mutation has become more complex. However, understanding which combinations of mutations spread widely and become established in new geographic regions versus those that disappear relatively quickly is essential for defining the trajectory of an ongoing epidemic. In this study, multiscale analysis of the wealth of genomic data generated over the course of the epidemic combined with in vivo laboratory data allowed trends in mutations and outbreak trajectory to be assessed. Mutations were detected throughout the genome via deep sequencing, and many variants appeared in multiple samples and in some cases become consensus. Similarly, amino acids that were previously consensus in pre-outbreak samples were detected as low frequency variants in epidemic strains. Protein structural models indicate that most of the mutations associated with the epidemic transmission occur on the exposed surface of viral proteins. At the macroscale level, consensus data was organized into large and interactive databases to allow the spread of individual mutations and combinations of mutations to be visualized and assessed for temporal and geographical patterns. Thus, the use of multiscale modeling for identifying mutations or combinations of mutations that impact epidemic transmission and phenotypic impact can aid the formation of hypotheses which can then be tested using reverse genetics.

16.
Artigo em Inglês | MEDLINE | ID: mdl-31818462

RESUMO

The Zika virus (ZIKV) is a mosquito-borne flavivirus that has reemerged as a serious public health problem around the world. Syndromes of infected people range from asymptomatic infections to severe neurological disorders, such as Guillain-Barré syndrome and microcephaly. Screening anti-ZIKV drugs derived from Chinese medicinal herbs is one method of identifying antiviral agents. In this paper, we report that (1) Cephalotaxine (CET), an alkaloid isolated from Cephalotaxus drupacea, was effective in inhibiting ZIKV activity in vitro (i.e., in Vero and A549 cell lines) and (2) the mechanisms which underlie these effects involve virucidal activity and a decrease in viral replication. Specifically, CET was found to decrease ZIKV RNA and viral protein expression, inhibit ZIKV replication, and inhibit ZIKV mRNA/protein production. We also determined that CET is effective in inhibiting dengue virus 1-4 (DENV1-4). Taken together, our findings indicate that CET could be an effective lead compound in the treatment of ZIKV and also suggest that further investigation and development of CET-derived drugs may lead to a new class of anti-Flavivirus medications.

17.
J Adv Vet Anim Res ; 6(4): 575-582, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31819889

RESUMO

Zika virus, a member of Flaviviridae is the etiology of Zika or Zika fever or Zika virus (ZIKV) disease characterized by mild symptoms similar to very mild form of Dengue or Chikungunya. The virus transmits through Aedes mosquitoes, particularly by Aedes aegypti. The most dangerous effect of ZIKV infection is the ability of the virus to cause microcephaly and congenital malformation to the newborn baby if the mother is infected. The neurological disorders including Guillain-Barré syndrome might be associated with adults and children due to ZIKV infections. Zika has emerged as a serious global public health problem as it has been found in 87 countries, particularly in Africa, America, and Asia and has no vaccine and treatment so far. Bangladesh is at a high risk of ZIKV infection and we consider ZIKV as a possible emerging threat for Bangladesh. This short review summarizes the insights of ZIKV infection, present status of the disease in Bangladesh and its neighboring countries, and recommendations for necessary preparations and strategies to be taken for effective controlling of the ZIKV infection in Bangladesh before getting any havoc.

18.
Nat Microbiol ; 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31792427

RESUMO

Zika virus (ZIKV) is a flavivirus that is closely related to other human pathogens, such as dengue virus (DENV)1. Primary transmission usually involves Aedes aegypti, which has expanded its distribution range considerably2, although rarer infection routes, including mother-to-fetus transmission, sexual contact and blood transfusion, have also been observed3-7. Primary ZIKV infection is usually asymptomatic or mild in adults, with quickly resolved blood viraemia, but ZIKV might persist for months in saliva, urine, semen, breast milk and the central nervous system8-12. During a recent ZIKV outbreak in South America, substantial numbers of neurological complications, such as Guillain-Barré syndrome, were reported13,14 together with cases of microcephaly and associated developmental problems in infants born to women infected with ZIKV during pregnancy15-20, highlighting the clinical importance of this infection. Analyses of the human immune response to ZIKV are lacking21-28, but the recent outbreak has provided an opportunity to assess ZIKV immunity using current immunological methods. Here, we comprehensively assess the acute innate and adaptive immune response to ZIKV infection in ten women who were recruited during early infection and followed through reconvalescence. We define a cascade of events that lead to immunological control of ZIKV, with previous exposure to DENV impacting some, but not all, mediators of antiviral immunity.

19.
Spec Care Dentist ; 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31794083

RESUMO

INTRODUCTION: Deciduous teeth eruption is connected to children's growth and development. In Brazil, with the increase in the occurrence of children born with microcephaly associated to exposure to Zika virus, studies about orofacial alterations were necessary. OBJECTIVE: Describe the chronology and sequence of deciduous teeth in children with microcephaly due to the fetal exposure to Zika virus. METHODOLOGY: A cross-sectional study involving 74 children of a neuropediatric reference unit in Salvador, Bahia, in 2017 was conducted. Through use of secondary data, interviews with mothers and children's exam, the population was characterized, the chronology and sequence of deciduous teeth eruption was registered, and the analysis of the variables was proceeded. RESULTS: The first eruption happened between 4 and 17 months of age and 52.70% had a delay in the eruption of incisors. The average eruption time for the maxilla varies from 17.92 (16.56-19.28; 95% CI) to 20.43 (19.35-21.51; 95% CI) months, and the jaw from 11.57 (6.85-18.99; 95% CI) to 20.20 (19.09-21.31; 95% CI) months. In 77.94% of population, the eruption of the first teeth was in the lower arch and in 33.82%, molars and/or canines erupted before the incisors. CONCLUSIONS: There were alteration in the chronology and sequence of deciduous teeth eruption.

20.
Viruses ; 11(12)2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31795144

RESUMO

Zika virus (ZIKV) recently emerged in the Western Hemisphere with previously unrecognized or unreported clinical presentations. Here, we identify two putative binding mechanisms of ancestral and emergent ZIKV strains featuring the envelope (E) protein residue asparagine 154 (ASN154) and viral phosphatidylserine (PS). Synthetic peptides representing the region containing ASN154 from strains PRVABC59 (Puerto Rico 2015) and MR_766 (Uganda 1947) were exposed to neuronal cells and fibroblasts to model ZIKV E protein/cell interactions and bound MDCK or Vero cells and primary neurons significantly. Peptides significantly inhibited Vero cell infectivity by ZIKV strains MR_766 and PRVABC59, indicating that this region represents a putative binding mechanism of ancestral African ZIKV strains and emergent Western Hemisphere strains. Pretreatment of ZIKV strains MR_766 and PRVABC59 with the PS-binding protein annexin V significantly inhibited replication of PRVABC59 but not MR_766, suggesting that Western hemisphere strains may additionally be capable of utilizing PS-mediated entry to infect host cells. These data indicate that the region surrounding E protein ASN154 is capable of binding fibroblasts and primary neuronal cells and that PS-mediated entry may be a secondary mechanism for infectivity utilized by Western Hemisphere strains.

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