Overview of latest articles and publications on ebola in PubMed. PubMed is a service of the US National Library of Medicine that includes over 18 million citations from MEDLINE and other life science journals.
- Distinct expression of IFIT1/2/3 and other antiviral genes between subsets of dendritic cells induced by DENV2 infection.
Zhang J, Sze DM, Yung BY, et al. Distinct expression of IFIT1/2/3 and other antiviral genes between subsets of dendritic cells induced by DENV2 infection. [JOURNAL ARTICLE]Immunology 2016 May 2.AbstractPublisher Full TextDengue virus (DENV) infection is an emerging public health hazard threatening inhabitants of the tropics and sub-tropics. Dendritic cells (DCs) are one of the major targets of DENV and the initiators of the innate immune response against the virus. However, current in vitro research on the DENV-DC interaction is hampered by the low availability of ex vivo DCs and donor variation. In the current study, we attempted to develop a novel in vitro DC model using immature dendritic cells derived from the myeloid leukaemia cell line MUTZ-3 (IMDCs) to investigate the DENV-DC interaction. The IMDCs morphologically and phenotypically resembled human immature monocyte-derived dendritic cells (IMMoDCs). However, the permissiveness of IMDCs to DENV2 was lower than that of IMMoDCs. RT-PCR arrays showed that a group of type I interferon (IFN)-inducible genes, especially IFIT1, IFITM1, and IFI27, were significantly up-regulated in IMMoDCs but not in IMDCs after DENV2 infection. Further investigation revealed that IFIT genes were spontaneously expressed at both transcriptional and protein levels in the naïve IMDCs but not in the naïve IMMoDCs. It is possible that the poor permissiveness of IMDCs to DENV2 was due to the high basal levels of IFIT proteins. We conclude that the IMDC model, although less permissive to DENV2, is a useful platform for studying the suppression mechanism of DENV2 and we expand the knowledge of cellular factors that modulate DENV2 infection in the human body. This article is protected by copyright. All rights reserved.
- Multiple Introductions of Dengue 2 Virus Strains into Saudi Arabia from 1992 to 2014.
El-Kafrawy SA, Sohrab SS, Abol Ela S, et al. Multiple Introductions of Dengue 2 Virus Strains into Saudi Arabia from 1992 to 2014. [JOURNAL ARTICLE]Vector Borne Zoonotic Dis 2016 May 2.AbstractPublisher Full TextPublisher Full TextDengue is a significant arboviral infection that represents a major public health concern worldwide. The infection is endemic in most parts of South East Asia, sub-Saharan Africa, and Latin America. Among the four dengue virus (DENV) serotypes, DENV-2 has been reported to be the predominant serotype in Saudi Arabia since 1992. However, virological and epidemiological data of DENV-2 from Saudi Arabia are severely deficient and require further investigations.Full genome sequencing of a recent DENV-2 isolate and phylogenetic analysis of all available DENV-2 sequences from Saudi Arabia.Based on full genome and envelope (E) gene sequence, we show that a recent isolate (DENV-2-Jeddah-2014) belongs to the Indian subcontinent lineage of the Cosmopolitan genotype with close similarity to recent strains from Pakistan. Interestingly, the E gene sequence of DENV-2-Jeddah-2014 isolate was slightly divergent from those previously identified in Saudi Arabia between 1992 and 2004 with three to nine amino acid (aa) substitutions. While our data show that the Cosmopolitan genotype is still circulating in Saudi Arabia, they highlight four distinct genetic groups suggesting at least four independent introductions into the Kingdom.The close clustering of DENV-2 isolates reported from Saudi Arabia between 1992 and 2014 with strains from countries providing the highest numbers of pilgrims attending either Hajj or Umrah pilgrimages (Indonesia, Pakistan, India) clearly suggests a role for pilgrims or expatriates coming from DENV endemic countries in DENV-2 importation into Saudi Arabia. Accordingly, continuous monitoring of the circulation of DENVs in Saudi Arabia must be implemented to undertake effective control and management strategies in the Kingdom. Screening of the pilgrims coming to perform Hajj and Umrah might help prevent the introduction of new DENV strains, which is expected to increase the burden of the disease not only in Saudi Arabia but also in other countries.
- Anticoagulation for Atrial Fibrillation after Resolution of Dengue Haemorrhagic Fever.
Veloso HH Anticoagulation for Atrial Fibrillation after Resolution of Dengue Haemorrhagic Fever. [Journal Article]J Clin Diagn Res 2016 Mar; 10(3):OL02.
- Zika virus infections imported from Brazil to Portugal, 2015.
Zé-Zé L, Prata MB, Teixeira T, et al. Zika virus infections imported from Brazil to Portugal, 2015. [Journal Article]IDCases 2016.:46-9.Zika virus is an emerging arbovirus transmitted by Aedes sp. mosquitoes like the Dengue and Chikungunya viruses. Zika virus was until recently considered a mild pathogenic mosquito-borne flavivirus with very few reported benign human infections. In 2007, an epidemic in Micronesia initiated the turnover in the epidemiological history of Zika virus and more recently, the potential association with congenital microcephaly cases in Brazil 2015, still under investigation, led the World Health Organization (WHO) to declare a Public Health Emergency of International Concern on February 1, 2016. Here, we present the clinical and laboratory aspects related to the first four imported human cases of Zika virus in Portugal from Brazil, and alert, regarding the high level of traveling between Portugal and Brazil, and the ongoing expansion of this virus in the Americas, for the threat for Zika virus introduction in Europe and the possible introduction to Madeira Island where Aedes aegypti is present.
- Open drug discovery for the Zika virus.
Ekins S, Mietchen D, Coffee M, et al. Open drug discovery for the Zika virus. [Journal Article]F1000Res 2016.:150.The Zika virus (ZIKV) outbreak in the Americas has caused global concern that we may be on the brink of a healthcare crisis. The lack of research on ZIKV in the over 60 years that we have known about it has left us with little in the way of starting points for drug discovery. Our response can build on previous efforts with virus outbreaks and lean heavily on work done on other flaviviruses such as dengue virus. We provide some suggestions of what might be possible and propose an open drug discovery effort that mobilizes global science efforts and provides leadership, which thus far has been lacking. We also provide a listing of potential resources and molecules that could be prioritized for testing as in vitro assays for ZIKV are developed. We propose also that in order to incentivize drug discovery, a neglected disease priority review voucher should be available to those who successfully develop an FDA approved treatment. Learning from the response to the ZIKV, the approaches to drug discovery used and the success and failures will be critical for future infectious disease outbreaks.
- First identification of kdr allele F1534S in VGSC gene and its association with resistance to pyrethroid insecticides in Aedes albopictus populations from Haikou City, Hainan Island, China.
Chen H, Li K, Wang X, et al. First identification of kdr allele F1534S in VGSC gene and its association with resistance to pyrethroid insecticides in Aedes albopictus populations from Haikou City, Hainan Island, China. [Journal Article]Infect Dis Poverty 2016; 5(1):31.AbstractPublisher Full TextAedes albopictus is distributed widely in China, as a primary vector of Dengue fever and Chikungunya fever in south of China. Chemical insecticide control is one of the integrated programmes to prevent mosquito-borne diseases. Long-term applications of pyrethroids have resulted in the development of resistance in Ae. albopictus populations in China. However, the susceptibility of Ae. albopictus to pyrethroids in Hainan Island was unclear. Knockdown resistance (kdr), caused by point mutations in the VGSC gene, is one of the mechanisms that confer resistance to DDT and pyrethroids. This study was to investigate the resistance level of Ae. albopictus populations in Haikou City to three pyrethroid insecticides, and elucidate the relationship between the resistant phenotype and kdr mutations.The Aedes albopictus samples were collected in Xinbu Island (XI), Longtang Town (LT), Shishan Town (ST), Baishamen Park (BP), and Flower Market (FM) from Haikou City, Hainan Island, China. The larval susceptibility to deltamethrin, permethrin and beta-cypermethrin was tested by larval bioassays, and adult susceptibility to deltamethrin and DDT was determined by adult bioassays. The degree of resistance was determined by resistance ratio value (RR50 > 3) for larvae and by mortality for adult. The kdr alleles at codon 1534 of the VGSC gene were genotyped. The relationship between kdr genotypes and resistant phenotypes was analyzed by Chi-square test.Out of five populations, assessed by larval bioassays, XI was susceptible to deltamethrin and permethrin; LT was susceptible to permethrin and beta-cypermethrin; and ST was susceptible to permithrin. FM and BP both were resistant to all of the three pyrethroids, and FM showed the highest degree of resistance, with RR50 values from 65.17 to 436.36. A total of 493 individuals from the larval bioassays were genotyped for kdr alleles. Five alleles were detected, including two wildtype alleles, TTC(F) (67.04 %) and TTT(F) (0.41 %), and three mutant alleles, TGC(C) (0.30 %), TCC(S) (31.54 %) and TTG(L) (0.71 %). There was a clear correlation between mutant alleles (or F1534S) and resistant phenotypes (P < 0.01).Two novel kdr mutant alleles F1534S and F1534L were detected in the pyrethroid resistant populations of Ae. albopictus in Haikou Hainan, China. For the first time, the mutant F1534S was associated with pyrethroid resistance in Ae. albopictus.
- Chandipura virus infection causing encephalitis in a tribal population of Odisha in eastern India.
Dwibedi B, Sabat J, Hazra RK, et al. Chandipura virus infection causing encephalitis in a tribal population of Odisha in eastern India. [Journal Article]Natl Med J India 2015 Jul-Aug; 28(4):185-7.The sudden death of 10 children in a tribal village of Kandhamal district, Odisha in eastern India led to this investigation.We conducted a door-to-door survey to identify cases. Antibodies for Chandipura, Japanese encephalitis, dengue, chikungunya and West Nile viruses were tested by ELISA in probable cases. Chandipura virus RNA was tested from both human blood samples and sand flies by reverse transcriptase polymerase chain reaction. We conducted vector surveys in domestic and peridomestic areas, and collected sand flies.Entomological investigations revealed the presence of Phlebotomus argentipes and Sergentomiya sp. Thirty-five patients presented with fever, 12 of them had altered sensorium including 4 who had convulsions. The blood samples of 21 patients were tested; four samples revealed Chandipura virusspecific IgM antibody.Chandipura virus infection causing encephalitis affected this tribal population in eastern India at 1212 m above sea level.
- Early central nervous system involvement in a young patient with dengue encephalitis.
Alice V, Cheong BM Early central nervous system involvement in a young patient with dengue encephalitis. [Journal Article]Med J Malaysia 2016 Feb; 71(1):41-3.A previously well 13-year-old boy presented with a short history of fever and altered mental status. His mother was admitted for dengue fever and there had been a recent dengue outbreak in their neighbourhood. He was diagnosed with dengue encephalitis as both his dengue non-structural protein 1 (NS-1) antigen and cerebrospinal fluid (CSF) dengue polymerase chain reaction (PCR) were positive. He did not have haemoconcentration, thrombocytopenia or any warning signs associated with severe dengue. He recovered fully with supportive treatment. This case highlights the importance of considering the diagnosis of dengue encephalitis in patients from dengue endemic areas presenting with an acute febrile illness and neurological symptoms.
- Dengue Virus Immunopathogenesis: Lessons Applicable to the Emergence of Zika Virus.
Olagnier D, Amatore D, Castiello L, et al. Dengue Virus Immunopathogenesis: Lessons Applicable to the Emergence of Zika Virus. [REVIEW, JOURNAL ARTICLE]J Mol Biol 2016 Apr 26.AbstractPublisher Full TextDengue is the leading mosquito-transmitted viral infection in the world. There are more than 390 million new infections annually; while the majority of infected individuals are asymptomatic or develop a self-limited dengue fever, up to 1 million clinical cases develop severe manifestations, including dengue hemorrhagic fever and shock syndrome, resulting in ~25,000 deaths annually, mainly in children. Gaps in our understanding of the mechanisms that contribute to dengue infection and immunopathogenesis have hampered the development of vaccines and antiviral agents. Some of these limitations are highlighted by the explosive re-emergence of another arthropod-borne flavivirus-Zika virus-spread by the same vector, the Aedes aegypti mosquito, that also carries dengue, yellow fever and chikungunya viruses. This review will discuss the early virus-host interactions in dengue infection, with emphasis on the interrelationship between oxidative stress and innate immune pathways, and will provide insight as to how lessons learned from dengue research may expedite therapeutic strategies for Zika virus.
- Multiple QTL determine dorsal abdominal scale patterns in the mosquito Aedes aegypti.
Mori A, Tsuda Y, Takagi M, et al. Multiple QTL determine dorsal abdominal scale patterns in the mosquito Aedes aegypti. [JOURNAL ARTICLE]J Hered 2016 Apr 29.AbstractPublisher Full TextThe mosquito, Aedes aegypti (L.) originated in Sub-Saharan Africa as a dark form sylvan species (A. aegypti formosus). Evolution of A. aegypti aegypti type form as a human commensal facilitated its colonization of most semitropical and tropical areas. We investigated the genetic basis for abdominal white scale presence that represents the diagnostic for sylvan A. aegypti formosus (scales absent), from type form (scales present) and A. aegypti queenslandensis form (dense scaling). We performed quantitative trait locus (QTL) mapping using three criteria for scale patterns among 192 F1 intercross progeny from matings between a queenslandensis type and an aegypti type form. Results identified 3 QTL determining scale patterns, and indicated that classification criteria impact robustness of QTL LOD support. Dark and light colored forms exist in sympatry, but vary in multiple phenotypic characteristics, including preferences for vertebrate host, oviposition container, house entering behavior, and dengue vector competence. Markers associated with 2 QTL regions reflected major reductions in recombination frequencies compared to the standard type form linkage map, suggestive of inversion polymorphisms associated with observed linkage disequilibrium between type-specific characteristics. Understanding the genic basis for differences in A. aegypti forms could inform efforts to develop new mosquito and arboviral disease control strategies.