Entomological Survey and () Prevalence in Sand Fly Species during an Outbreak of Cutaneous Leishmaniasis in Quintana Roo State, Mexico.

: Localized cutaneous leishmaniasis is a neglected vector-borne disease that has become a serious public health problem in the Yucatan Peninsula. Although more than 60% of cases originate from the state of Quintana Roo, it is one of the least explored areas in terms of incriminating vectors of the Leishmania parasite. Additionally, cases of leishmaniasis have increased substantially in that region in recent years.

Detection of Wolbachia and Leishmania DNA in sand flies (Diptera: Psychodidae, Phlebotominae) from a focus of cutaneous leishmaniasis in Tabasco, Mexico.

Phlebotomine sand flies are the main vectors of Leishmania genus species worldwide; therefore, the detection of some reproductive parasites, such as Wolbachia, has been considered a possible strategy for biological control. In Mexico, leishmaniasis cases have been recorded in 25 states, yet only two sand fly species have been related to Wolbachia spp. Although the state of Tabasco has a high number of leishmaniasis cases, only few studies have been done on sand fly species.

Association of Single-Nucleotide Polymorphisms in Immune-Related Genes with Development of Dengue Hemorrhagic Fever in a Mexican Population.

Single-nucleotide polymorphisms (SNPs) occurring in immune-related genes have been associated with risk or protection for development of dengue, depending on ethnicity. Here, we genotyped seven SNPs located in immune response-related genes to identify their association with severe forms of dengue in patients from an endemic region in Mexico. One hundred and thirty-eight patients with dengue fever (DF), thirty-one dengue hemorrhagic fever (DHF) patients, as well as 304 healthy donors were genotyped by using a TaqMan-based approach.

Hepatitis C virus molecular evolution: transmission, disease progression and antiviral therapy.

Hepatitis C virus (HCV) infection represents an important public health problem worldwide. Reduction of HCV morbidity and mortality is a current challenge owned to several viral and host factors. Virus molecular evolution plays an important role in HCV transmission, disease progression and therapy outcome.

Vertical transmission of hepatitis C virus: a tale of multiple outcomes.

Globally, hepatitis C virus (HCV) infection affects approximately 130 million people and 3 million new infections occur annually. HCV is also recognized as an important cause of chronic liver disease in children. The absence of proofreading properties of the HCV RNA polymerase leads to a highly error prone replication process, allowing HCV to escape host immune response.

Participation of CD161(+) and invariant natural killer T cells in pediatric asthma exacerbations.

Asthma has been defined as a disease of chronic airway inflammation in which many cells and cellular products participate with variable degrees of airflow obstruction and hyperresponsiveness that lead to recurrent episodes of wheezing, breathlessness, chest tightness, and coughing. Prominent among these cellular elements are two cell types referred to as the invariant natural killer T (iNKT) cells and a subpopulation of T cells expressing the molecule CD161, which are both thought to play a role in the pathogenesis of asthma. Although the presence of iNKT and other CD161(+) cells in murine models has been associated with asthma, relatively few studies have been performed in the adult patient with asthma that have been often conflicting and even fewer studies are available in children.

Epidemiology of varicella in Mexico.

Background: The epidemiological patterns of varicella-zoster virus (VZV) infection, which are strongly associated with climate, are characterized by more frequent infections occurring among children in temperate regions than in the tropics. In temperate regions, varicella exhibits a seasonal cyclic behavior in which the number of cases increases significantly during the winter and spring seasons, further supporting the role of environmental factors in disease transmission. However, the underlying mechanisms responsible for this distinctive behavior are not fully understood.

Identification of hepatitis C virus transmission using a next-generation sequencing approach.

Here, we describe a transmission event of hepatitis C virus (HCV) among injection drug users. Next-generation sequencing (NGS) was used to assess the intrahost viral genetic variation. Deep amplicon sequencing of HCV hypervariable region 1 allowed for a detailed analysis of the structure of the viral population.

Specific detection of naturally occurring hepatitis C virus mutants with resistance to telaprevir and boceprevir (protease inhibitors) among treatment-naïve infected individuals.

The use of telaprevir and boceprevir, both protease inhibitors (PI), as part of the specifically targeted antiviral therapy for hepatitis C (STAT-C) has significantly improved sustained virologic response (SVR) rates. However, different clinical studies have also identified several mutations associated with viral resistance to both PIs. In the absence of selective pressure, drug-resistant hepatitis C virus (HCV) mutants are generally present at low frequency, making mutation detection challenging.

Is ultra-violet radiation the main force shaping molecular evolution of varicella-zoster virus?

Background: Varicella (chickenpox) exhibits a characteristic epidemiological pattern which is associated with climate. In general, primary infections in tropical regions are comparatively less frequent among children than in temperate regions. This peculiarity regarding varicella-zoster virus (VZV) infection among certain age groups in tropical regions results in increased susceptibility during adulthood in these regions.

Molecular epidemiology of autochthonous dengue virus strains circulating in Mexico.

Dengue virus (DENV) is the most important arthropod-borne viral infection in humans. Here, the genetic relatedness among autochthonous DENV Mexican isolates was assessed. Phylogenetic and median-joining network analyses showed that viral strains recovered from different geographic locations are genetically related and relatively homogeneous, exhibiting limited nucleotide diversity.

Interleukin-28B genotyping by melt-mismatch amplification mutation assay PCR analysis using single nucleotide polymorphisms rs12979860 and rs8099917, a useful tool for prediction of therapy response in hepatitis C patients.

Several studies have identified associations between single nucleotide polymorphisms (SNPs) occurring near the interleukin-28B (IL-28B) gene and response to antiviral treatment among hepatitis C virus (HCV) patients. Here, we describe a reliable melt-mismatch amplification mutation assay (melt-MAMA) PCR-based genotyping method for IL-28B which can be used in the management of HCV patients, helping to better define the course of therapy.

Taenia solium: immune response against oral or systemic immunization with purified recombinant calreticulin in mice.

Recombinant functional Taenia solium calreticulin (rTsCRT) confers different degrees of protection in the experimental model of intestinal taeniosis in hamsters. The aim of this study was to evaluate the immune response induced after oral or systemic immunization with an electroeluted rTsCRT in BALB/c mice. Oral immunization elicited high fecal IgA and the production of IL-4 and IL-5 by mesenteric lymph node cells after in vitro stimulation with rTSCRT, indicating a Th2 response.