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.
- Insect-specific flaviviruses, a worldwide widespread group of viruses only detected in insects.
Calzolari M, Zé-Zé L, Vázquez A, et al. Insect-specific flaviviruses, a worldwide widespread group of viruses only detected in insects. [JOURNAL ARTICLE]Infect Genet Evol 2015 Jul 30.Several flaviviruses are important pathogens for humans and animals (Dengue viruses, Japanese encephalitis virus, Yellow-fever virus, Tick-borne encephalitis virus, West Nile virus). In recent years, numerous novel and related flaviviruses without known pathogenic capacity have been isolated worldwide in the natural mosquito population. However, phylogenetic studies have shown that genomic sequences of these viruses diverge from other flaviviruses. Moreover, these viruses seem to be exclusive of insects (they do not seem to grow on vertebrate cell lines), and were already defined as mosquito-only flaviviruses or insect-specific flaviviruses. At least eleven of these viruses were isolated worldwide, and sequences ascribable to other eleven putative viruses were detected in several mosquito species. A large part of the cycle of these viruses is not well known, and their persistence in the environment is poorly understood. These viruses are detected in a wide variety of distinct mosquito species and also in sandflies and chironomids worldwide; a single virus, or the genetic material ascribable to a virus, was detected in several mosquito species in different countries, often in different continents. Furthermore, some of these viruses are carried by invasive mosquitoes, and do not seem to have a depressive action on their fitness. The global distribution and the continuous detection of new viruses in this group point out the likely underestimation of their number, and raise interesting issues about their possible interactions with the pathogenic flaviviruses, and their influence on the bionomics of arthropod hosts. Some enigmatic features, as their integration in the mosquito genome, the recognition of their genetic material in DNA forms in field-collected mosquitoes, or the detection of the same virus in both mosquitoes and sandflies, indicate that the cycle of these viruses has unknown characteristics that could be of use to reach a deeper understanding of the cycle of related pathogenic flaviviruses.
- [Neonatal Dengue. Presentation of clinical cases].
Romero-Santacruz E, Lira-Canul JJ, Pacheco-Tugores F, et al. [Neonatal Dengue. Presentation of clinical cases]. [English Abstract, Journal Article]Ginecol Obstet Mex 2015 May; 83(5):308-15.Dengue is an infectious disease caused by a flavivirus, with four serotypes, transmitted by the mosquito Aedes aegypti. In Mexico it is a public health problem, especially in the region of central and southeast of the country. The disease can be asymptomatic or present serious forms and even death. It is confirmed by detection of the NS1 Antigen; IgM antibodies, polymerase chain reaction and virus isolation. The vertical transmission to de newborn has been little studied. 7 cases in neonates from November to December 2011 are reported. All patients were male, obtained by caesarean section between 34 and 40 weeks of gestation, whose mothers were enrolled with fever and symptoms associated with dengue disease and serology positive for dengue. Six with positive AgNS1 and one positive IgM; one mother died. All the newborns had positive serology for dengue, 4 with positive AgNS1 and 3 positive IgM. The clinical features of the newborn ranged from asymptomatic to one serious dengue fever, shock and hemorrhage. The symptomatic 6 attended with thrombocytopenia, changes in temperature and unspecific disturbance. The severity of mothers conditioned disrepair product at birth, but not with subsequent gravity of the new born. Vertical trasmission of dengue should be suspected in risk areas, to maintain vigilance and to give early treatment. Also is neccesary promote the realization of specific diagnostic and therapeutic guidelines to the neonatal period.
- Dual inhibitors of the dengue and West Nile virus NS2B-NS3 proteases: Synthesis, biological evaluation and docking studies of novel peptide-hybrids.
Bastos Lima A, Behnam MA, El Sherif Y, et al. Dual inhibitors of the dengue and West Nile virus NS2B-NS3 proteases: Synthesis, biological evaluation and docking studies of novel peptide-hybrids. [JOURNAL ARTICLE]Bioorg Med Chem 2015 Jul 15.Dengue virus (DENV) and West Nile virus (WNV) are mosquito-borne arboviruses responsible for causing acute systemic diseases and severe health conditions in humans. The discovery of therapies capable to prevent infections or treat infected individuals remains an important challenge, since no vaccine or specific efficient treatment could be developed so far. In this context, we present herein the synthesis, characterization, biological evaluation and docking studies of novel peptide-hybrids based on 2,4-thiazolidinedione scaffolds containing non-polar groups. The most promising compound has an IC50 of 0.75μM against WNV protease, which represents a seventyfold improvement in activity compared to our previously reported compounds. Experimental results and docking studies are in agreement with the hypothesis that a non-polar group in the scaffold is important to obtain interactions between the inhibitors and a hydrophobic pocket in the substrate recognition region of the DENV and WNV NS2B-NS3 serine proteases.
- Hyperferritinemic syndrome: Still's disease and catastrophic antiphospholipid syndrome triggered by fulminant Chikungunya infection: a case report of two patients.
Betancur JF, Navarro EP, Echeverry A, et al. Hyperferritinemic syndrome: Still's disease and catastrophic antiphospholipid syndrome triggered by fulminant Chikungunya infection: a case report of two patients. [JOURNAL ARTICLE]Clin Rheumatol 2015 Aug 2.There are four medical conditions characterized by high levels of ferritin, the macrophage activation syndrome (MAS), adult onset Still' s disease (AOSD), catastrophic antiphospholipid syndrome (CAPS), and septic shock, that share similar clinical and laboratory features, suggesting a common pathogenic mechanism. This common syndrome entity is termed "the hyperferritinemic syndrome." Here, we describe two different cases of hyperferritinemic syndrome triggered by Chikungunya fever virus infection: a 21-year-old female with SLE and a 32-year-old male patient who developed AOSD after the coinfection of dengue and Chikungunya viruses.
- Malaria in Poland in 2013.
Stępień M Malaria in Poland in 2013. [Journal Article]Przegl Epidemiol 2015; 69(2):273-5.AbstractPublisher Full TextEvaluation of the epidemiological situation of imported malaria in Poland in 2013 compared to the data from previous years.The assessment was performed based on the results of the analysis of individual reports sent to the NIPH-NIH by sanitary-epidemiological stations and aggregated data published in the annual bulletins "Infectious diseases and poisonings in Poland". Cases were registered according to the case definition criteria applicable in the EU countries.In 2013, a total of 36 imported malaria cases were registered in Poland, 15 more than in 2012. No deaths were recorded. As much as 80% of all cases were imported from African countries, of whom the majority came from Nigeria, 14% from Asia and 6% from South America. Concurrent infection with dengue virus was confirmed in one person coming back from Philippines. Plasmodium species was determined in 35 of 36 cases by blood film or PCR test. Invasion with P. falciparum and P. vivax was found in 23 (66%) and 9 (26%) cases, respectively. There was also one case of each of the following: P. ovale, P. malariae and mixed invasion. As in previous years, in most cases, the invasion was associated with tourist trips (47%) or work-related travels (36%). Immigrants or students visiting the country of origin accounted for 11% of patients, in two cases (6%) purpose of the journey was not determined. As many as 7 patients used chemoprophylaxis, including two persons who took drugs in compliance with the recommendations.Despite a significant increase in the number of cases compared to previous years, the total number of imported malaria remains low. Persistent large number of delays in the diagnosis and a high percentage of severe malaria cases indicate the need to raise doctors awareness of the possibility of malaria incidence. Travelers should be also constantly reminded of the need to inform their GPs about the stay in the malaria endemic areas in the event of fever after returning.imported malaria, epidemiology, Poland, 2013.
- Molecular Insight into Dengue Virus Pathogenesis and Its Implications for Disease Control.
Diamond MS, Pierson TC Molecular Insight into Dengue Virus Pathogenesis and Its Implications for Disease Control. [Journal Article, Review]Cell 2015 Jul 30; 162(3):488-92.Dengue virus (DENV) is a mosquito-transmitted RNA virus that infects an estimated 390 million humans each year. Here, we review recent advances in our understanding of the biology of DENV and describe knowledge gaps that have impacted the development of effective vaccines and therapeutics.
- Extracellular synthesis of silver nanoparticles using Bacillus megaterium against malarial and dengue vector (Diptera: Culicidae).
Banu AN, Balasubramanian C Extracellular synthesis of silver nanoparticles using Bacillus megaterium against malarial and dengue vector (Diptera: Culicidae). [JOURNAL ARTICLE]Parasitol Res 2015 Aug 2.AbstractPublisher Full TextBiosynthesis of silver nanoparticles has provoked nowadays and alternative to physical and chemical approaches. In the present study, silver nanoparticles (AgNPs) were synthesized extracellular method using Bacillus megaterium. The AgNPs formations were confirmed initially through color change, and the aliquots were characterized through UV-visible spectrophotometer, followed by scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) spectroscopy, and Fourier transform infrared (FTIR) spectra. The surface plasmon resonance band was shown at 430 nm in UV-vis spectrophotometer. The bioreduction was categorized through identifying the compounds responsible for the AgNP synthesis, and the functional group present in B. megaterium cell-free culture was scrutinized using FTIR. The topography and morphology of the particles were determined using SEM. In addition, this biosynthesized AgNPs were found to show higher insecticidal efficacy against vector mosquitoes. The LC50 and LC90 were found to be 0.567, 2.260; 0.90, 4.44; 1.349, 8.269; and 1.640, 9.152 and 0.240, 0.955; 0.331, 1.593; 0.494, 2.811; and 0.700, 4.435 with respect to the first, second, third, and fourth instar larvae of Culex quinquefasciatus and Aedes aegypti. All the calculated χ (2) values are highly significant compared with the tabulated value. Therefore, B. megaterium-synthesized silver nanoparticles would be used as a potent larvicidal agent against Cx. quinquefasciatus and Ae. aegypti.
- HCV NS5A Up-Regulates COX-2 Expression via IL-8-Mediated Activation of the ERK/JNK MAPK Pathway.
Chen WC, Tseng CK, Chen YH, et al. HCV NS5A Up-Regulates COX-2 Expression via IL-8-Mediated Activation of the ERK/JNK MAPK Pathway. [JOURNAL ARTICLE]PLoS One 2015; 10(7):e0133264.AbstractPublisher Full TextChronic hepatitis C virus (HCV) infection leads to intrahepatic inflammation and liver cell injury, which are considered a risk factor for virus-associated hepatitis, cirrhosis, and hepatocellular carcinoma worldwide. Inflammatory cytokines are critical components of the immune system and influence cellular signaling, and genetic imbalances. In this study, we found that cyclooxygenase-2 (COX-2) and interleukin-8 (IL-8) were significantly induced by HCV infection and HCV NS5A expression, and induction of COX-2 correlated with HCV-induced IL-8 production. We also found that the ERK and JNK signaling pathways were involved in the regulation of IL-8-mediated COX-2 induction in response to HCV infection. Using a promoter-linked reporter assay, we identified that the C/EBP regulatory element within the COX-2 promoter was the dominant factor responsible for the induction of COX-2 by HCV. Silencing C/EBP attenuated HCV-induced COX-2 expression. Our results revealed that HCV-induced inflammation promotes viral replication, providing new insights into the involvement of IL-8-mediated COX-2 induction in HCV replication.
- [Information and Communication Technologies (ICTs): alternative or complement for surveillance, prevention and control of dengue in the Americas?]
Culquichicón-Sánchez C, Ramos-Cedano E, Chumbes-Aguirre D, et al. [Information and Communication Technologies (ICTs): alternative or complement for surveillance, prevention and control of dengue in the Americas?] [JOURNAL ARTICLE]Rev Chilena Infectol 2015 Jun; 32(3):363-364.Publisher Full Text
- Retrospective screening of acute undifferentiated fever serum samples with universal flavivirus primers.
Khongwichit S, Libsittikul S, Yoksan S, et al. Retrospective screening of acute undifferentiated fever serum samples with universal flavivirus primers. [JOURNAL ARTICLE]J Infect Dev Ctries 2015; 9(7):760-764.AbstractPublisher Full TextFever is a common symptom of many tropical diseases and in many cases the etiologic agent remains unidentified as a consequence of either the etiologic agent not being part of routine diagnostic screening or as a consequence of false negatives on standard diagnostic tests.This study screened a well characterized panel of 274 serum samples collected on day of admission from adult patients with acute undifferentiated fever admitted to a hospital in Nakhon Ratchasima, Thailand by RT-PCR using pan-flavivirus degenerate primers.Subsequent clinical diagnosis was achieved for 38 of the patients, and included 19 cases of dengue fever. RT-PCR screening identified seven positive samples (2.5%) which were revealed by sequence analysis to be dengue virus 1 (2 cases), dengue virus 2 (2 cases) and dengue virus 3 (3 cases). Only 5 out of 19 (26%) serum samples from patients subsequently diagnosed with dengue were positive, but 2 samples which clinically remained undiagnosed were shown to be positive for dengue virus. Sequence analysis suggested that the dengue virus 3 cases occurred as a result of importation of a strain of dengue from India or China. No other flaviviruses were identified.No evidence was found of other flaviviruses besides dengue circulating in this population. Despite improved diagnostic tests, cases of dengue are still evading correct diagnosis.