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Hang J.,U.S. Army | Forshey B.M.,Us Naval Medical Research Unit No 6 | Yang Y.,U.S. Army | Fiestas Solorzano V.,Instituto Nacional Of Salud | And 4 more authors.
PLoS ONE | Year: 2014

Group C orthobunyaviruses (family Bunyaviridae, genus Orthobunyavirus), discovered in the 1950s, are vector-borne human pathogens in the Americas. Currently there is a gap in genomic information for group C viruses. In this study, we obtained complete coding region sequences of reference strains of Caraparu (CARV), Oriboca (ORIV), Marituba (MTBV) and Madrid (MADV) viruses, and five clinical isolates from Peru and Bolivia, using an unbiased de novo approach consisting of random reverse transcription, random anchored PCR amplification, and high throughput pyrosequencing. The small, medium, and large segments encode for a 235 amino acid nucleocapsid protein, an approximately 1430 amino acid surface glycoprotein polyprotein precursor, and a 2248 amino acid RNA-dependent RNA polymerase, respectively. Additionally, the S segment encodes for an 83 amino acid non-structural protein, although this protein is truncated or silenced in some isolates. Phylogenetically, three clinical isolates clustered with CARV, one clustered with MTBV, and one isolate appeared to be a reassortant or a genetic drift resulted from the high variability of the medium segment which was also seen in a few other orthobunyaviruses. These data represent the first complete coding region sequences for this serocomplex of pathogenic orthobunyaviruses. The genome-wide phylogeny of reference strains is consistent with the antigenic properties of the viruses reported in the original serological studies conducted in the 1960s. Comparative analysis of conserved protein regions across group C virus strains and the other orthobunyavirus groups revealed that these group C viruses contain characteristic domains of potential structural and functional significance. Our results provide the basis for the developments of diagnostics, further genetic analyses, and future epidemiologic studies of group C viruses. Source

Clark J.,University of California at Los Angeles | Salvatierra J.,Cayetano Heredia Peruvian University | Segura E.,University of California at Los Angeles | Salazar X.,Cayetano Heredia Peruvian University | And 6 more authors.
AIDS and Behavior | Year: 2013

Role-based sexual identities structure male same-sex partnerships and influence HIV/STI epidemiology among MSM in Latin America. We explored shifting relationships between sexual roles, identities and practices among MSM in Lima, Peru, and implications for HIV/STI prevention. Patterns of HIV/STI epidemiology reflected differential risks for transmission within role-based partnerships with relatively low prevalences of HIV, syphilis, and HSV-2 but higher prevalences of urethral gonorrhea/chlamydia among activo MSM compared with moderno and pasivo participants. Qualitative analysis of how MSM in Peru integrate sexual identities, roles, and practices identified four key themes: pasivo role as a gay approximation of cultural femininity; activo role as a heterosexual consolidation of masculinity; moderno role as a masculine reconceptualization of gay identity; and role-based identities as social determinants of partnership, network, and community formation. The concept of role-based sexual identities provides a framework for HIV prevention for Latin American MSM that integrates sexual identities, practices, partnerships, and networks. © 2013 Springer Science+Business Media, LLC. Source

Cruz C.D.,Us Naval Medical Research Unit 6 | Forshey B.M.,Us Naval Medical Research Unit 6 | Vallejo E.,Servicio Departamental de Salud | Agudo R.,Servicio Departamental de Salud | And 5 more authors.
Emerging Infectious Diseases | Year: 2012

To better describe the genetic diversity of hantaviruses associated with human illness in South America, we screened blood samples from febrile patients in Chapare Province in central Bolivia during 2008-2009 for recent hantavirus infection. Hantavirus RNA was detected in 3 patients, including 1 who died. Partial RNA sequences of small and medium segments from the 3 patients were most closely related to Andes virus lineages but distinct (<90% nt identity) from reported strains. A survey for IgG against hantaviruses among residents of Chapare Province indicated that 12.2% of the population had past exposure to >1 hantaviruses; the highest prevalence was among agricultural workers. Because of the high level of human exposure to hantavirus strains and the severity of resulting disease, additional studies are warranted to determine the reservoirs, ecologic range, and public health effect of this novel strain of hantavirus. Source

Wang H.-C.H.,U.S. Army | Choi J.-H.,U.S. Army | Greene W.A.,U.S. Army | Plamper M.L.,U.S. Army | And 5 more authors.
Military Medicine | Year: 2014

Background: Blast-induced ocular trauma is a frequent cause of morbidity for survivors of improvised explosive devices. Blast overpressure (BOP) of 120 ± 7 KPa has been shown to cause damage to lungs, brain, and gut in a rat model; however, the effects of BOP on ocular tissues have not been characterized. To elucidate the pathophysiology of blast-induced ocular trauma, ocular tissues from rats subjected to blast were examined for evidence of apoptosis by the detection of activated caspase 3 and TUNEL assay in their ocular tissues. Methods: A compressed air shock tube was used to deliver 120 ± 7 KPa of BOP for duration of 2 msec to the right side of the rats. Rats were then euthanized at specific time points after blast exposure (3 hours, 24 hours, 48 hours). Ocular tissues were processed for immunohistochemistry to detect activated caspase 3 and TUNEL assay. Tissues were evaluated for relative levels of positive signal as compared to nonblast exposed controls. Results: Activated caspase 3 was detected in the optic nerve, ganglion layer, and inner nuclear layer post blast exposure. At 24 and 48 hours, the inner nuclear layer from the right side had more cells with activated caspase 3. In the optic nerve, the highest levels of activated caspase 3 were detected on the right side at 24 hours post blast. Conclusion: BOP of 120 ± 7 KPa induces optic neuropathy and retinal damage. In both the optic nerve and retina, caspase 3 was activated in the right and left sides following blast exposure. The results of this study reveal that blast exposure induces apoptosis in both the optic nerve and retinal tissues. © Association of Military Surgeons of the U.S. All rights reserved. Source

Stoddard S.T.,University of California at Davis | Stoddard S.T.,U.S. National Institutes of Health | Wearing H.J.,University of New Mexico | Reiner Jr. R.C.,University of California at Davis | And 13 more authors.
PLoS Neglected Tropical Diseases | Year: 2014

Introduction:Long-term disease surveillance data provide a basis for studying drivers of pathogen transmission dynamics. Dengue is a mosquito-borne disease caused by four distinct, but related, viruses (DENV-1-4) that potentially affect over half the world's population. Dengue incidence varies seasonally and on longer time scales, presumably driven by the interaction of climate and host susceptibility. Precise understanding of dengue dynamics is constrained, however, by the relative paucity of laboratory-confirmed longitudinal data.Methods:We studied 10 years (2000-2010) of laboratory-confirmed, clinic-based surveillance data collected in Iquitos, Peru. We characterized inter and intra-annual patterns of dengue dynamics on a weekly time scale using wavelet analysis. We explored the relationships of case counts to climatic variables with cross-correlation maps on annual and trimester bases.Findings:Transmission was dominated by single serotypes, first DENV-3 (2001-2007) then DENV-4 (2008-2010). After 2003, incidence fluctuated inter-annually with outbreaks usually occurring between October and April. We detected a strong positive autocorrelation in case counts at a lag of ∼70 weeks, indicating a shift in the timing of peak incidence year-to-year. All climatic variables showed modest seasonality and correlated weakly with the number of reported dengue cases across a range of time lags. Cases were reduced after citywide insecticide fumigation if conducted early in the transmission season.Conclusions:Dengue case counts peaked seasonally despite limited intra-annual variation in climate conditions. Contrary to expectations for this mosquito-borne disease, no climatic variable considered exhibited a strong relationship with transmission. Vector control operations did, however, appear to have a significant impact on transmission some years. Our results indicate that a complicated interplay of factors underlie DENV transmission in contexts such as Iquitos. © 2014. Source

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