Opsoclonus-myoclonus-ataxia syndrome associated with central nervous system HIV-1 escape phenomenon. / Síndrome opsoclono-mioclono-ataxia asociado a fenómeno de escape viral por virus de la inmunodeficiencia humana en el sistema nervioso central.

INTRODUCTION: Opsoclonus-myoclonus-ataxia (OMA) syndrome is a rare neurological disorder characterized by involuntary conjugate saccadic eye movements, myoclonus, and ataxia. Few reports exist on patients with HIV and OMA. CASE REPORT: A 41-year-old man diagnosed with HIV-1 infection in 1997 coursed with multiple anti-retroviral schemes as a consequence of poor adherence. In 2008 he presented an HIV-1 viral load of 100,000 copies/mL and a CD4+ T cell count of 10 cells/mm3. In 2013 our patient arrived with an 11-month history of progressive opsoclonus and ataxia. He had undetectable plasma HIV-1 RNA load and CD4+ of 606 cells/mm3. No opportunistic infections were found. Cerebrospinal fluid analysis showed mildly elevated protein concentration and HIV-1 viral load of 534 copies/mL. Cerebrospinal fluid co-receptor tropism test showed selective CCR5 usage. A brain magnetic resonance imaging showed hippocampal atrophy and T2-weighted hyperintensities. Our patient exhibited a dramatic recovery and cerebrospinal fluid HIV clearance after adjustment of anti-retroviral treatment based on genotyping resistance and tropism analyses. CONCLUSIONS: In patients with HIV presenting cengral nervous system dysfunction without opportunistic infections, cerebro-spinal fluid and plasma HIV-1 viral load, resistance and tropism tests should be performed to assess a potential viral escape and to design the appropriate anti-retroviral therapy in an individual patient basis.

TITLE: Síndrome opsoclono-mioclono-ataxia asociado a fenómeno de escape viral por virus de la inmunodeficiencia humana en el sistema nervioso central.Introducción. El síndrome opsoclono-mioclono-ataxia (OMA) es un trastorno neurológico infrecuente caracterizado por movimientos oculares conjugados sacádicos involuntarios, mioclonías y ataxia. Existen pocos casos en la bibliografía de pacientes con virus de la inmunodeficiencia humana (VIH) y OMA. Caso clínico. Varón de 41 años y diagnóstico de infección por el VIH-1 desde 1997, que cursó con múltiples esquemas antirretrovirales debido a una pobre adhesión al tratamiento. En 2008 presentó una carga viral de 100.000 copias/mL y una cuenta linfocitaria CD4+ de 10 células/mm3. En 2013 sufrió un cuadro progresivo de 11 meses de evolución caracterizado por opsoclonía y ataxia. En ese momento, su carga viral era indetectable, y la cuenta de CD4+, de 606 células/mm3. Se descartaron infecciones oportunistas. El examen del líquido cefalorraquídeo demostró hiperproteinorraquia leve y una carga viral de 534 copias/mL. El examen del tropismo de correceptor en el líquido cefalorraquídeo demostró un uso selectivo de CCR5. La resonancia magnética cerebral objetivó atrofia hipocámpica e hiperintensidades en las secuencias ponderadas en T2. El paciente mostró una recuperación clínica franca y un aclaramiento de la carga viral en el líquido cefalorraquídeo tras el ajuste de antirretrovirales basado en la resistencia de genotipo y el análisis de tropismo. Conclusiones. En pacientes con infección por el VIH y disfunción del sistema nervioso central sin infecciones oportunistas, debería llevarse a cabo una determinación de la carga viral en el plasma y el líquido cefalorraquídeo para descartar un potencial fenómeno de escape viral, así como exámenes de resistencia y tropismo para diseñar el tratamiento antirretroviral adecuado.

Immediate treatment of acute HIV in a tertiary healthcare center: bridging gaps in communication using smartphones.

OBJECTIVES: Early initiation of antiretroviral therapy (ART) during acute HIV infection is associated with favourable clinical and epidemiological outcomes. Barriers to prompt treatment initiation limit the benefits of universal access to ART in Mexico. We sought to create an algorithm for the immediate detection and treatment of patients with acute HIV infection. METHODS: A nationwide cohort of patients with acute HIV infection was created in 2015. In order to identify cases and treat them promptly at our centre, an interdisciplinary group coordinated through an instant-messaging tool using smart phones was established. When a probable case was detected, a discussion was initiated to confirm the diagnosis and facilitate the administrative processes to initiate ART as soon as possible. We compared time to ART initiation with that in a comparison group of patients with chronic HIV infection enrolled during the same period (May 2015 to February 2017) through routine care, using survival analysis estimators and log-rank tests. RESULTS: We recruited 29 patients with acute HIV infection. The median time to ART initiation was 2 days in these patients, in contrast to 21 days for patients with chronic infection. There were no significant differences in the percentages of patients engaged in care, on treatment or virologically suppressed at 1 year of follow-up. CONCLUSIONS: Implementing immediate ART initiation programmes is feasible in Mexico, in spite of the substantial administrative barriers that exist in the country. More extensive replication of this model in other centres and in patients with chronic infection is warranted to evaluate its effect on the continuum of care.

Loci Identification of a N-acyl Homoserine Lactone Type Quorum Sensing System and a New LysR-type Transcriptional Regulator Associated with Antimicrobial Activity and Swarming in Burkholderia Gladioli UAPS07070.

A random transposition mutant library of B. gladioli UAPS07070 was analyzed for searching mutants with impaired microbial antagonism. Three derivates showed diminished antimicrobial activity against a sensitive strain. The mutated loci showed high similarity to the quorum sensing genes of the AHL-synthase and its regulator. Another mutant was affected in a gene coding for a LysrR-type transcriptional regulator. The production of toxoflavin, the most well known antimicrobial-molecule and a major virulence factor of plant-pathogenic B. glumae and B. gladioli was explored. The absence of a yellowish pigment related to toxoflavin and the undetectable transcription of toxA in the mutants indicated the participation of the QS system and of the LysR-type transcriptional regulator in the regulation of toxoflavin. Additionally, those genes were found to be related to the swarming phenotype. Lettuce inoculated with the AHL synthase and the lysR mutants showed less severe symptoms. We present evidence of the participation of both, the quorum sensing and for the first time, of a LysR-type transcriptional regulator in antibiosis and swarming phenotype in a strain of B. gladioli.

Effects of two new steroids and cyproterone on some biomarkers of oxidative stress and serotonergic system on rat prostate and brain.

The purpose of this study was to evaluate the effect of cyproterone acetate (CPA, A) compared with new synthetic steroids 3alpha-acetoxy-5,6-epoxy-16-pregnen-20-one (B) and 17alpha-hydroxy-16beta-methyl-1,4,6-pregnatriene-3,20-dione (C) in rat prostate and brain. Groups of animals were treated either with A, B or C (4 mg kg(-1) day(-1)) by the intraperitoneal route for 5 days. Levels of reduced glutathione (GSH), 5-hydroxy-indole acetic acid (5-HIAA), lipid peroxidation (as thiobarbituric acid reactive substances, TBARS) and the activities of Na(+), K(+)- and total ATPases were assayed in prostate and brain for each group of animals including a control group. No appreciable changes were shown in Na(+), K(+)-ATPase and total ATPases and TBARS on prostate and brain of rats that received A, B and C steroids. However, the levels of GSH and 5-HIAA decreased significantly (P < 0.05) in both tissues for the steroids assayed. It is concluded that CPA and the homologues B and C steroids induce changes in the levels of GSH and serotonin in rat prostate and brain.

Degradation of immobilized azo dyes by Klebsiella sp. UAP-b5 isolated from maize bioadsorbent.

The degradation of two immobilized dyes by Klebsiella sp. UAP-b5 was studied. In batch experiments, the azo dyestuffs Basic Blue 41 and Reactive Black 5 were immobilized onto corn cobs by adsorption, and the adsorption process was characterized by a pseudo-second-order kinetic equation. Klebsiella sp. UAP-b5 was previously isolated from the corn waste and shown to decolorize these dyes in liquid systems. Here, we demonstrate anaerobic decolorization and reductive biodegradation of these dyes by means of spectrophotometry, HPLC, and IR spectroscopy of the solid waste and desorption solutions. We also demonstrate adsorption of compounds that resemble known degradation products.

Comparative phylogeography of Trypanosoma rangeli and Rhodnius (Hemiptera: Reduviidae) supports a long coexistence of parasite lineages and their sympatric vectors.

To make reliable interpretations about evolutionary relationships between Trypanosoma rangeli lineages and their insect vectors (triatomine bugs of the genus Rhodnius) and, thus, about the determinant factors of lineage segregation within T. rangeli, we compared phylogenies of parasite isolates and vector species. Sixty-one T. rangeli isolates from invertebrate and vertebrate hosts were initially evaluated in terms of polymorphism of the spliced-leader gene (SL). Further analysis based on SL and SSUrRNA sequences from 33 selected isolates, representative of the overall phylogenetic diversity and geographical range of T. rangeli, supported four phylogenetic lineages within this species. By comparing the phylogeny of Rhodnius species with that inferred for T. rangeli isolates and through analysis of the geographical range of the isolates, we showed that there is a very significant overlap in the distribution of Rhodnius species and T. rangeli lineages. Congruence between phylogeographical analysis of both T. rangeli lineages and complexes of Rhodnius species are consistent with the hypothesis of a long coexistence of parasites and their vectors, with lineage divergence associated with sympatric species of Rhodnius apparently without association with particular vertebrate hosts. Separation of T. rangeli isolates from vectors of distinct complexes living in sympatry favours the absence of gene flow between the lineages and suggests evolution of T. rangeli lineages in independent transmission cycles, probably associated to specific Rhodnius spp. ecotopes. A polymerase chain reaction assay based on SL intergenic sequences was developed for simultaneous identification and lineage genotyping of T. rangeli in epidemiological surveys.

Trypanosoma rangeli: RAPD-PCR and LSSP-PCR analyses of isolates from southeast Brazil and Colombia and their relation with KPI minicircles.

This study presents the first genetic characterization of five Trypanosoma rangeli isolates from Minas Gerais, in the southeast of Brazil and their comparison with Colombian populations by minicircle classification, RAPD-PCR and LSSP-PCR analyses. Our results demonstrated a homogenous T. rangeli population circulating among Didelphis albiventris as reservoir host in Brazil while heterogeneous populations were found in different regions of Colombia. KP1(+) minicircles were found in 100% isolates from Brazil and in 36.4% of the Colombian samples, whereas the KP2 and KP3 minicircles were detected in both groups. RAPD-PCR and LSSP-PCR profiles revealed a polymorphism within KP1(+) and KP1(-) T. rangeli populations and allowed the division of T. rangeli in two branches. The Brazilian KP1(+) isolates were more homogenous than the KP1(+) isolates from Colombia. The RAPD-PCR were entirely consistent with the distribution of KP1 minicircles while those obtained by LSSP-PCR were associated in 88.9% and 71.4% with KP1(+) and KP1(-) populations, respectively.

Extracellular HIV-1 Nef protein modulates lytic activity and proliferation of human CD8+ T lymphocytes.

The effect of extracellular HIV Nef (exNef) protein on the induction of lytic activity and proliferation of CD8+T lymphocytes from 18 donors was studied. At 10 ng/ml, exNef-induced a 2- to 8-fold enhancement of basal lytic activity in cells from all donors in an allogeneic induction assay, whereas it was ineffective at 100ng/ml. The extent of enhancement was inversely correlated with the basal level of lytic activity without exNef. Only in combination with PHA did both exNef concentrations stimulate proliferation, and in a manner inversely related to the effect of PHA alone. Thus, concentrations of exNef commonly found in sera of HIV-infected patients were found to modulate the induction of lytic activity and proliferation of CD8+ T lymphocytes in vitro, to an extent strongly dependent on the quite variable responsiveness of each donor. These findings point to Nef as a potential agent for modulating CD8+ T cell function in pathogenesis and therapy.

Cystoisospora belli: in vitro multiplication in mammalian cells.

Intracellular development of Cystoisospora belli was demonstrated in 4 different mammalian cell lines. Human ileocecal adenocarcinoma (HCT-8), epithelial carcinoma of lung (A549), Madin-Darby bovine kidney (MDBK), and African green monkey kidney (VERO) were exposed in vitro to C. belli sporozoites, which had been isolated from the feces of HIV-AIDS patients. Parasites invaded all the cellular types between 4 and 12h after exposure and multiplication was demonstrated after 24 h. Grater number of merozoites formed in VERO cells, followed by HCT-8. In the MDBK and HCT-8 cells, the parasitophorous vacuole was less evident and immobile merozoites were observed in the cytoplasm. In VERO cells, one or several parasitophorous vacuoles contained up to 16 mobile sporozoites. No oocysts were found in any of the cell types used. VERO cells may be suitable for studies of the interaction between parasite and host cells.

Interstitial cells of Cajal in patients with chagasic megacolon originating from a region of old endemicity.

UNLABELLED: Megacolon is the second most frequent and most important digestive manifestation of Chagas' disease. It is characterized by motor disorders and dilatation of the distal segments of the colon. Several theories have been presented to explain the physiopathology of chagasic megacolon, e.g. the plexus theory. OBJECTIVE: In the present study the distribution of interstitial cells of Cajal (ICC) was evaluated in colon biopsies from chronic chagasic patients originating from a region of old endemicity for Trypanosoma cruzi and for comparison in subjects with other colon disorders. The chagasic patients had been submitted to colectomy for the investigation of other possible mechanisms underlying the physiopathogenesis of megacolons. DESIGN STUDY: Twenty-two colon biopsies (15 from chagasic patients and 7 from nonchagasic patients) were examined. ICC were identified by immunohistochemistry by using the anti-CD117 antibody. The number of ICC was determined in longitudinal and circular muscle layers and in the myenteric plexus, and the results were analyzed by the Kruskal-Wallis and Student t-tests. RESULTS: A reduced number of ICC was observed in all layers and in the myenteric plexus of patients with chagasic megacolon (P<0.05). CONCLUSIONS: We conclude that the physiopathological manifestations observed in the large bowel of chagasic patients originate from alterations that occur in the ICC, which play an important role in the control of gut motility.

Chagas' disease susceptibility/resistance: linkage disequilibrium analysis suggests epistasis between major histocompatibility complex and interleukin-10.

Association between the major histocompatibility complex (MHC) and the susceptibility/resistance to acquire Chagas' disease has been largely demonstrated. To study the role of candidate genes in this susceptibility/resistance to Chagas, we designed a population-genetic-based case-control approach (chagasic n = 104 and controls n = 60) and tested the presence of genotype and linkage disequilibrium on microsatellite loci establishing specific landmarks for the MHC, interleukin (IL)-2, IL-2Rbeta chain, IL-4, IL-10, and natural resistance-associated mactophage protein 1 (NRAMP1). After demonstrating no genetic stratification among cases and controls (F(st) were not different from 0), we found significant allelic differences among chagasic patients and controls at microsatellite locus D6S291 (MHC) and at the microsatellite pointing out the IL-10. At the MHC, we found significant differences between patients and controls in Hardy-Weinberg equilibrium-expected genotype proportions. Additionally, MHC II-locus-inferred haplotypes in chagasic patients exhibited strong significant departures from the expected proportions predicted by the second Mendelian law. The linkage disequilibrium pattern at MHC involves a region of approximately 10 cM. These results replicate previous analyses and suggest that presence of epistasis between MHC with humoral systems, such as IL-10, could be underlying the susceptibility/resistance to Chagas' disease.

On the dynamics of a spherical scaffold in rotating bioreactors.

We analyze the dynamics of a spherical scaffold in rotating bioreactors (or clinostats). The idealized clinostat environment consists of a purely rotational flow that is perpendicular to a gravitational field. We confirm through a detailed analytical study that lift effects considerably alter the position of the equilibrium point reached by the scaffolds in the (vertical) direction collinear to the gravitational field. This result holds for small particle and shear Reynolds numbers. Our analysis shows that the inertial lift effect is negligible in the horizontal direction. We show that for all rotations of practical interest, and for the range of particle Reynolds number smaller than unity, the vertical coordinate of the equilibrium point is strongly affected by consideration of lift effects. For light (heavy) particles, inclusion of lift in the formation forces the equilibrium position to be below (above) the horizontal plane that contains the axis of rotation. The equilibrium point for light particles is stable and therefore is observable experimentally. The equilibrium point for heavy particles is unstable. We also estimate the stress level applied to the scaffold and derive an algebraic expression that indicates that the stress level acting on the scaffold decreases with increasing shear Reynolds number.

Relationship between Trypanosoma cruzi and human chagasic megaesophagus: blood and tissue parasitism.

The persistence of Trypanosoma cruzi in tissue and blood of 52 patients in the digestive form of chronic Chagas disease was studied. These patients had chagasic megaesophagus and underwent corrective surgery. Parasitologic (xenodiagnosis, hemoculture, or both), histopathologic (hematoxylin and eosin, and peroxidase-anti-peroxidase staining), and molecular (polymerase chain reaction [PCR] followed by slot-blot hybridization) tests were used in the analysis. The presence of T. cruzi, its genomic fragments, or its antigens could be detected in 98% (51 of 52) of the patients. The parasite was randomly identified in 76.9% of esophageal tissues and in 90.4% by PCR and in 73.1% by parasitologic methods from the blood. Fifty percent (26 of 52) of tissue samples had inflammation, 80.8% of which was associated with the parasite. Trypanosoma cruzi was also identified unassociated with inflammatory alterations. Higher tissue parasitism and intense inflammatory processes were observed in esophageal tissue from patients with Grade IV megaesophagus. These data demonstrate that in the digestive form of Chagas' disease, particularly in cases of megaesophagus, T. cruzi is frequently found, both in blood and tissues and may contribute to the pathogenic mechanisms involved.

The marsupial Didelphis albiventris is an improbable host of Paracoccidioides brasiliensis in an endemic area of paracoccidioidomycosis in Minas Gerais, Brazil.

To determine whether Didelphis albiventris is naturally infected with Paracoccidioides brasiliensis, 20 specimens of this mammal were studied by both direct cultivation of their viscera (spleen, liver and lungs) and by inoculation of Swiss mice by the intraperitoneal route with a suspension of fragments of these viscera. No fungal growth or structures similar to this fungus were detected. Probably D. albiventris is not frequently infected with P. brasiliensis.

Novel nitrogen-fixing acetic acid bacteria, Gluconacetobacter johannae sp. nov. and Gluconacetobacter azotocaptans sp. nov., associated with coffee plants.

Diazotrophic bacteria were isolated, in two different years, from the rhizosphere and rhizoplane of coffee (Coffea arabica L.) plants cultivated in Mexico; they were designated as type DOR and type SAd isolates. They showed characteristics of the family Acetobacteraceae, having some features in common with Gluconacetobacter (formerly Acetobacter) diazotrophicus, the only known N2-fixing species of the acetic acid bacteria, but they differed from this species with regard to several characteristics. Type DOR isolates can be differentiated phenotypically from type SAd isolates. Type DOR isolates and type SAd isolates can both be differentiated from Gluconacetobacter diazotrophicus by their growth features on culture media, their use of amino acids as nitrogen sources and their carbon-source usage. These results, together with the electrophoretic mobility patterns of metabolic enzymes and amplified rDNA restriction analysis, suggested that the type DOR and type SAd isolates represent two novel N2-fixing species. Comparative analysis of the 16S rRNA sequences revealed that strains CFN-Cf55T (type DOR isolate) and CFN-Ca54T (type SAd isolate) were closer to Gluconacetobacter diazotrophicus (both strains had sequence similarities of 98.3%) than to Gluconacetobacter liquefaciens, Gluconacetobacter sacchari (similarities < 98%) or any other acetobacteria. Strain CFN-Cf55T exhibited low levels of DNA-DNA reassociation with type SAd isolates (mean 42%) and strain CFN-Ca54T exhibited mean DNA-DNA reassociation of 39.5% with type DOR isolates. Strains CFN-Cf55T and CFN-Ca54T exhibited very low DNA reassociation levels, 7-21%, with other closely related acetobacterial species. On the basis of these results, two novel N2-fixing species are proposed for the family Acetobacteraceae, Gluconacetobacter johannae sp. nov. (for the type DOR isolates), with strain CFN-Cf55T (= ATCC 700987T = DSM 13595T) as the type strain, and Gluconacetobacter azotocaptans sp. nov. (for the type SAd isolates), with strain CFN-Ca54T (= ATCC 70098ST = DSM 13594T) as the type strain.

Plasmodium falciparum acid basic repeat antigen (ABRA) peptides: erythrocyte binding and biological activity.

Non overlapping 20-mer peptides, covering the complete sequence of acid basic repeat antigen (ABRA) of Plasmodium falciparum, were synthesised and tested in binding assays to erythrocytes. Five peptides localised in the N-terminal region coded 2148 (121LQSHKKLIKALKKNIESYQN(140)), 2149 (141KKHLIYKNKSYNPLLLSCVK(160)), 2150 (161KMNMLKENVDYIQKNQNLFK(180)), 2152 (201YKSQGHKKETSQNQNENNDN(220)) and 2153 (221QKYQEVNDEDDVNDEEDTND(240)) specifically bind to erythrocytes. These peptides bind independently of the peptide and erythrocyte charge, with high affinity (Kd between 70 and 180 nM) and the hydrophobic interaction is important for this binding ( approximately 30% hydrophobic critical residues). These results allow us define a specific erythrocyte binding region (residues 121-240), which may bound to at least three different binding sites on erythrocytes. Peptide 2153 shares the underlined sequence 221QKYQEVNDEDDVNDEEDTND(240) with an earlier 18-mer peptide recognised by human exposed sera. Peptides number 2148 and 2149 in vitro inhibit erythrocyte invasion by merozoites. We found that 2149 peptide and some of its glycine analogues show specific haemolytic and/or antimicrobial activity. We discuss a possible role of ABRA or its regions in the merozoite invasion of erythrocyte.

The marsupial Didelphis albiventris is an improbable host of Paracoccidioides brasiliensis in an endemic area of paracoccidioidomycosis in Minas Gerais, Brazil

To determine whether Didelphis albiventris is naturally infected with Paracoccidioides brasiliensis, 20 specimens of this mammal were studied by both direct cultivation of their viscera (spleen, liver and lungs) and by inoculation of Swiss mice by the intraperitoneal route with a suspension of fragments of these viscera. No fungal growth or structures similar to this fungus were detected. Probably D. albiventris is not frequently infected with P. brasiliensis

Hepatocyte metaplasia in experimental chagasic pancreatitis: preliminary report.

Beginning the study of chronic pathologic changes in pancreas of hamsters experimentally infected with Trypanosoma cruzi Vic strain, hepatocyte metaplasia was observed in one animal from infected group. This is the first report of oncocytes in Chagas' disease, which could be due to aberrant regenerative response to pancreas inflammatory process.

[Viral hepatitis C in patients with terminal chronic renal insufficiency. III. Viral quantification]. / Hepatitis viral C en pacientes con insuficiencia renal crónica terminal. III. Cuantificación viral.

BACKGROUND: We have previously shown that the prevalence of hepatitis associated with the hepatitis C virus (HCV) in patients with end stage renal disease in our institution is 10.2%. However, quantification of viral RNA in plasma and its relation with clinical variables has never been studied in our patients. Thus, the aim of the present work was to quantify the HCV viral load in patients with ESRD in dialysis, and to correlate these values with the dialysis modality and the viral genotype. METHODS: We performed a transverse, prospective and comparative study in patients with HCV infection in hemodialysis, continuous ambulatory peritoneal dialysis and patients in peritoneal dialysis, but with history of hemodialysis. Viral load was quantified with RT-PCR by using a commercial kit known as Amplicor HCV 2.0. Clinical variables studied were: age, gender, end stage renal disease etiology, modality and time in dialysis, transfusions, serum albumin, aminotransferases, blood urea nitrogen, and serum creatinine. RESULTS: Twenty four patients in dialysis with HCV infection entered into the study. Of these patients, 25% were on peritoneal dialysis, 29% on peritoneal dialysis with history of hemodialysis, and 46% were in hemodialysis. The average viral load (copies x 10(6)/mL) was 1.41 +/- 3.01. Viral load was lower in patients on peritoneal dialysis than in patients treated, or with history of hemodialysis (0.20 +/- 0.12 vs 2.04 +/- 0.88; p < 0.05). We observed no differences in viral load among patients with different viral genotypes. DISCUSSION: The average viral load of our patients in dialysis is lower than the levels usually observed in hepatitis C infected patients without end stage renal disease. The lower viral load in patients treated with peritoneal dialysis, and no history of hemodialysis, probably denotes lower risk of chronic liver disease in these subpopulation.