Characterization of the dengue outbreak in Nuevo Leon state, Mexico, 2010.

We studied serotypes circulating dengue virus (DENV) cases, entomological Breteau index, rain-fall index and epidemiology of groups affected during the 2010 outbreak in Nuevo Leon, Mexico. From 2,271 positive cases, 94% were dengue classic and 6% dengue hemorrhagic fever; DENV1 was mainly isolated (99%) (Central-American lineage of American-African-genotype). We found correlation between two environmental phenomena (Increment of rainfall and vector-indexes) (p ≤ 0.05) with epidemiological, clinical and risk of DENV-1 ongoing transmission.

Pre-synaptic histamine H3 receptors modulate glutamatergic transmission in rat globus pallidus.

The globus pallidus, a neuronal nucleus involved in the control of motor behavior, expresses high levels of histamine H(3) receptors (H(3)Rs) most likely located on the synaptic afferents to the nucleus. In this work we studied the effect of the activation of rat pallidal H(3)Rs on depolarization-evoked neurotransmitter release from slices, neuronal firing rate in vivo and turning behavior. Perfusion of globus pallidus slices with the selective H(3)R agonist immepip had no effect on the release of [(3)H]-GABA ([(3)H]-γ-aminobutyric acid) or [(3)H]-dopamine evoked by depolarization with high (20 mM) K(+), but significantly reduced [(3)H]-d-aspartate release (-44.8 ± 2.6% and -63.7 ± 6.2% at 30 and 100 nM, respectively). The effect of 30 nM immepip was blocked by 10 µM of the selective H(3)R antagonist A-331440 (4'-[3-[(3(R)-dimethylamino-1-pyrrolidinyl]propoxy]-[1,1-biphenyl]-4'-carbonitrile). Intra-pallidal injection of immepip (0.1 µl, 100 µM) decreased spontaneous neuronal firing rate in anaesthetized rats (peak inhibition 68.8±10.3%), and this effect was reversed in a partial and transitory manner by A-331440 (0.1 µl, 1 mM). In free-moving rats the infusion of immepip (0.5 µl; 10, 50 and 100 µM) into the globus pallidus induced dose-related ipsilateral turning following systemic apomorphine (0.5 mg/kg, s.c.). Turning behavior induced by immepip (0.5 µl, 50 µM) and apomorphine was partially prevented by the local injection of A-331440 (0.5 µl, 1 mM) and was not additive to the turning evoked by the intra-pallidal injection of antagonists at ionotropic glutamate receptors (0.5 µl, 1 mM each of AP-5, dl-2-amino-5-phosphonovaleric acid, and CNQX, 6-nitro-7-sulphamoylbenzo[f]quinoxaline-2,3-dione). These results indicate that pre-synaptic H(3)Rs modulate glutamatergic transmission in rat globus pallidus and thus participate in the control of movement by basal ganglia.

Dengue virus antibodies in blood donors from an endemic area.

We evaluated the incidence of anti-Dengue virus (DENV) antibodies and dengue viremia in a region of Mexico with a high prevalence of dengue. DENV is the most important arthropod-borne virus in terms of human morbidity and mortality in America We tested 800 blood donors from a tertiary care teaching hospital that provides care in Northeast Mexico, to identify anti-DENV IgM and IgG antibodies by enzyme-linked immunosorbent assay (ELISA) and DENV genome by reverse transcription polymerase chain reaction (RT-PCR). In addition, routine tests for donors including Brucella, Hepatitis C virus (HCV), Venereal Disease Research Laboratory (VDRL), HIV-1 and HBsAg identification were performed. We found that 59% of donors were reactive for anti-DENV IgG and none of them had reported recent DENV infection; however, 16 (2%) were reactive for anti-DENV IgM antibodies. None of them were viremic at the time of donation. Routine tests showed that the prevalence of anti-Brucella was 0.71%, anti-HCV 0.71%, anti-HIV-1-2 0.14%, HBsAg 0.14% and VDRL test 0.57%. Although DENV transmission by blood transfusion had not been confirmed in Mexico, the finding of a high prevalence of anti-DENV IgM-positive donors with asymptomatic manifestations and the recent viremia reported in blood donors suggests that this route of transmission might be possible.

Additive effect of ethanol and HCV subgenomic replicon expression on COX-2 protein levels and activity.

The mechanisms by which alcohol exacerbates liver injury in patients with hepatitis C are unknown. We used the hepatitis C virus (HCV) subgenomic replicon cell system to evaluate the effect of ethanol on HCV replication and viral protein synthesis. Our results demonstrate that alcohol stimulates HCV replicon expression at both HCV-RNA and protein levels. Furthermore, we observed that ethanol treatment showed an additive effect in cyclooxygenase-2 (COX-2) protein expression and activity already induced by HCV viral proteins, and in turn increased HCV viral expression. Our results suggest that COX-2 activity is involved in ethanol-induced HCV-RNA and NS5A protein expression, because acetylsalicylic acid (ASA), a COX-1/2 inhibitor, blocked this induction and downregulated COX-2 protein expression and activity. Therefore, we suggest that ethanol increases HCV replication expression, at least in part, by upregulating a key cellular regulator of oxidative stress pathway known as COX-2 or its products.

The molecular epidemiology of HIV type 1 of men in Mexico.

Genotypic characteristics of human immunodeficiency virus type 1 (HIV-1) in Mexico were investigated in a multicenter study that involved centers in five geographic regions of the country. Study samples (n = 65) collected from male patients in 1998-1999 were sequenced within the C2-V5 region of the gp120 env gene. Phylogenetic analysis revealed that subtype B predominates in Mexico. The level of interpatient nucleotide diversity (mean value of 8.9%) was congruent with multiple introductions of the virus and the "aging" epidemic in Mexico. One-third of samples (30.8% of cases) showed polymorphism within the crown of the V3 loop demonstrating non-GPGR motifs. Two new motifs in the V3 loop crown - HPGG and GPEG - were observed. The evolution of the AIDS epidemic in Mexico should be closely monitored since non-B HIV-1 subtypes might be introduced. The nucleotide sequences were deposited in the GenBank under accession numbers AF200855-AF200869, AF200871-AF200892, and AF200894-AF200921.

Octreotide therapy of large-volume refractory AIDS-associated diarrhea: a randomized controlled trial.

OBJECTIVE: To compare the effect of octreotide (a long-acting somatostatin analog) to that of antidiarrheal therapy plus placebo on large-volume refractory AIDS-associated diarrhea. DESIGN: A randomized controlled trial. SETTING: Referral-based clinic and hospital in a tertiary care center. PATIENTS: Twenty male patients with AIDS and refractory diarrhea, with stool volume > 1000 ml/day who failed to improve after initial supportive management. All patients finished the study. INTERVENTIONS: Patients were randomly given either octreotide in doses of 100, 200 and 300 micrograms subcutaneously every 8 h, or high doses of loperamide and diphenoxylate orally plus placebo subcutaneously for 10 days. MAIN OUTCOME MEASURES: Bowel movements and stool volume were registered before and every day after treatment by the patients themselves and the nursing personnel. RESULTS: Patients from both groups were similar for age, time of AIDS diagnosis, duration of diarrhea and etiology. Baseline mean bowel movements per day (9.4 +/- 2.8 in the octreotide group versus 10 +/- 3.1 in controls) and baseline mean stool volume (2753 +/- 840 versus 2630 +/- 630 ml/day, respectively) were similar in both groups before therapy (P < 0.05). Mean bowel movements per day after 10 days of therapy was 2.1 +/- 1.6 in the octreotide group versus 7 +/- 3 in controls (P < 0.05). Mean stool volume after 10 days of therapy was 485 +/- 480 in the octreotide group versus 1080 +/- 420 ml/day in controls (P < 0.05). Complete response (stool volume < 250 ml/day) was observed in two patients from the octreotide group and none from controls; partial response (decrease > 50% in stool volume) in four and two; and no response (decrease < 50% or no change) in four and eight (P < 0.05), respectively. Side-effects occurred in eight out of 10 octreotide patients and three out of 10 controls (P < 0.05), but none were significant to result in discontinuation of medication. CONCLUSION: Octreotide proved to be superior to conventional therapy in this short-term treatment of large-volume refractory AIDS-associated diarrhea.

[9 cases of encephalitis in an epidemic outbreak of exanthematous diseases]. / Nueve casos de encefalitis en un brote epidémico de enfermedades exantemáticas.

We report here nine cases of encephalitis secondary to exanthematous diseases diagnosed from March to June 1990 at the University Hospital in Monterrey, Mexico. Two of the cases were secondary to measles, three to rubella, and four to varicella. One patient with varicella died, and the histopathological study showed findings compatible with viral encephalitis. The sex distribution was four males and five females with ages ranging from two to fourteen years. The most common clinical manifestations were hemiparesia, intracranial hypertension, meningism and altered consciousness. The CSF examination showed lymphocytic pleocytosis (mean = 295 cells), increased protein levels (mean = 118 mg/dL) and a normal glucose value in eight cases. These findings and the presence of an exanthematous disease suggested viral invasion of the CNS. Magnetic resonance imaging showed high intensity signal areas mainly in the frontal and temporal lobes. In this paper we compare the relative incidence of encephalitis secondary to exanthematous diseases in our geographical area during the last four years.

[Severe diarrhea in AIDS treated with a somatostatin analog. Report of a case]. / Diarrea grave en el síndrome de inmunodeficiencia adquirida, tratada con un análogo de somatostatina. Reporte de un caso.

We herein report a 30 years old male patient with AIDS and Cryptosporidium diarrhea diagnosed by intestinal biopsy. After some days of unsuccessful conventional anti-diarrheal treatment, an analog of somatostatin (octreotide acetate) Sandostatin was started. The stool volume and the bowel movements decreased dramatically and in spite of some collateral effects the patient could be clinically improved and discharged from the hospital.

Hemangioma facial gigante y fistulas arteriovenosas pulmonares. / Giant facial hemangioma and arteriovenous pulmonary fistulas

Se describe un caso con la rara asociacion de hemangioma gigante de la cara principalmente y grandes fistulas arteriovenosas del pulmon y del cuello que produjeron insuficiencia cardiaca irreversible y la muerte de una nina de ano y medio de edad.Se presentan los estudios especializados que permitieron fundar el diagnostico y se discute la fisiopatologia de esta asociacion