First report of Stegomyia aegypti (= Aedes aegypti) in Mexico City, Mexico.

Stegomyia aegypti (= Aedes aegypti) (Diptera: Culicidae) is a species of mosquito that is currently widespread in Mexico. Historically, the mosquito has been distributed across most tropical and subtropical areas lower than 1700 m a.s.l. Currently, populations that are found at higher altitudes in regions with cold and dry climates suggest that these conditions do not limit the colonization and population growth of S. aegypti. During a survey of mosquitoes in September 2015, larvae of S. aegypti mosquitoes were found in two different localities in Mexico City, which is located at about 2250 m a.s.l. Mexico City is the most populous city in Mexico and has inefficient drainage and water supply systems. These factors may result in the provision of numerous larval breeding sites. Mosquito monitoring and surveillance are now priorities for the city.

Drug resistance in Mexico: results from the National Survey on Drug-Resistant Tuberculosis.

OBJECTIVE: To present estimations obtained from a population-level survey conducted in Mexico of prevalence rates of mono-, poly- and multidrug-resistant strains among newly diagnosed cases of pulmonary tuberculosis (TB), as well as the main factors associated with multidrug resistance (combined resistance to isoniazid and rifampicin). DESIGN: Study data came from the National Survey on TB Drug Resistance (ENTB-2008), a nationally representative survey conducted during 2008-2009 in nine states with a stratified cluster sampling design. Samples were obtained for all newly diagnosed cases of pulmonary TB in selected sites. Drug susceptibility testing (DST) was performed for anti-tuberculosis drugs. RESULTS: DST results were obtained for 75% of the cases. Of these, 82.2% (95%CI 79.5-84.7) were susceptible to all drugs. The prevalence of multidrug-resistant TB (MDR-TB) was estimated at 2.8% (95%CI 1.9-4.0). MDR-TB was associated with previous treatment (OR 3.3, 95%CI 1.1-9.4). CONCLUSIONS: The prevalence of drug resistance is relatively low in Mexico. ENTB-2008 can be used as a baseline for future follow-up of drug resistance.

Enhanced survival from CLP-induced sepsis following late administration of low doses of anti-IFNγ F(ab')2 antibody fragments.

OBJECTIVE: To assess the impact of different doses of anti-interferon gamma (anti-IFNγ) F(ab')2 fragments, administered prophylactically, on survival and on serum concentration of cytokines in a murine model of sepsis induced by cecal ligation and puncture (CLP). We further explore the impact of therapeutic administration of the most protective dose on survival. SUBJECTS AND TREATMENT: Balb/c mice were prophylactically treated by the intraperitoneal route with anti-IFNγ initiated 2 h before CLP and every 24 h for a total of five times in each of the following doses: 0.01, 0.1, or 1 mg/kg. Sham and control groups received sterile saline solution in a similar scheme. METHODS: Serum tumor necrosis factor (TNF), interleukin (IL)-1ß, IL-6, IL-10 and IFNγ were measured at 3, 24 and 48 h after CLP by ELISA. Survival curves were compared using a Mantel-Haenzel method. RESULTS: Significant prophylactic protection was found only with 0.01 mg/kg, in association with regulation of IL-1ß and IL-10 concentrations. As therapy, anti-IFNγ fragments were protective only when initiated 24 h after CLP. CONCLUSIONS: Delicate modulation of IFNγ at the correct timing, even when the septic process has begun, is an exciting alternative to explore in the treatment of sepsis.

Anti-tumor necrosis factor alpha F(ab')2 antibody fragments protect in murine polymicrobial sepsis: concentration and early intervention are fundamental to the outcome.

BACKGROUND: Negative results are frequent using anti-TNFalpha antibodies in sepsis models and clinical trials. METHODS AND RESULTS: Different prophylactic doses of anti-TNFalpha F(ab')2 antibody fragments were compared for the prevention of death by sepsis induced by cecal ligation and puncture (CLP) in mice. High (10 mg/kg) and very low (0.01 and 0.1 mg/kg) concentrations of anti-TNFalpha antibody fragments were not the most adequate for treating polymicrobial sepsis, since they did not significantly improve survival. To the contrary, intermediate doses (1 mg/kg) significantly protected the challenged animals. Protective activity was also observed when administration of the antibody fragments was initiated early (up to 30 min) after CLP. CONCLUSIONS: These results suggest that in processes where excessive production of cytokines is involved, the aim should be to return them to their physiologically acting range but not to inhibit their production. The timing of initiating therapy should also be considered in order to maximize the possible benefits.

Identification of two homologous antigenic peptides derived from L1 HPV-16 and 18 proteins specific for the HLA-B*3901 allele.

In this work we present evidence that the homologous peptides IHSMNSTIL and IHSMNSSIL derived from L1 HPV-16 and 18 proteins respectively, and with high specificity for the allele HLA-B*3901, according with an algorithm prediction program, induced T cell stimulation in patients with advanced cervical cancer positive for HPV-16 or 18 infection and for the HLA-B*3901 allele. Interestingly, T lymphocytes derived from a patient with HPV-18 infection and stimulated with the peptide IHSMNSTIL were capable to kill a cervical cancer cell line named Rova, derived from the tumor of the same patient. In addition, the cytotoxic activity was strongly increased when this cell line was previously treated with hrIFN-gamma. These results suggest that the CTL immune response to L1 HPV-16 and 18 protein derived epitopes is maintained in patients with advanced cervical cancer within specific alleles, and opens the possibility that homologous epitopes may be used in the generation of prophylactic vaccines for cervical tumors bearing different HPV-types.

Identification of peptides presented by HLA class I molecules on cervical cancer cells with HPV-18 infection.

In this work we eluted peptides from purified class I MHC molecules, isolated from a novel human cervical carcinoma cell line (INBL), generated in our laboratory and positive for HPV-18 infection. A fraction of these peptides was capable of stimulating T lymphocytes obtained from a donor matched for HLA-Cw4 and who was also HPV-18+. Direct N-terminal Edman degradation of these peptides, revealed the sequence (XQFPIFLQF) that matched 85% with the sequence NVFPIFLQM localized in between the 54 and 62 residues of the HPV-18 L1 protein. After stimulation with the synthetic peptide NVFPIFLQM, T lymphocytes from the donor were capable to lyse INBL cells. Our results provide evidence of the existence of naturally occurring viral epitopes presented on cervical cancer cells by the HLA-Cw4 allele, that could be useful for immunotherapy on this type of patient.

Molecular characterization of the tight junction protein ZO-1 in MDCK cells.

Most of the information on the structure and function of the tight junction (TJ) has been obtained in MDCK cells. Accordingly, we have sequenced ZO-1 in this cell type, because this protein is involved in the response of the TJ to changes in Ca2+, phosphorylation, and the cytoskeleton. ZO-1 of MDCK cells comprises 6805 bp with a predicted open reading frame of 1769 amino acids. This sequence is 92 and 87% homologous to human and mouse ZO-1, respectively. Two nuclear sorting signals located at the PDZ1 and GK domains and 17 SH3 putative binding sites at the proline-rich domain were detected. We found two new splicing regions at the proline-rich region: beta had not been reported in human and mouse counterparts, and gamma, which was previously sequenced in human and mouse ZO-1, is now identified as a splicing region. The expression of different beta and gamma isoforms varies according to the tissue tested. With the information provided by the sequence, Southern blot, and PCR experiments we can predict a single genomic copy of MDCK-ZO-1 that is at least 13.16 kb long. MDCK-ZO-1 mRNA is 7.4 kb long. Its expression is regulated by calcium, while the expression of MDCK-ZO-1 protein is not.