Increased Helicobacter pylori-associated gastric cancer risk in the Andean region of Colombia is mediated by spermine oxidase.

Helicobacter pylori infection causes gastric cancer, the third leading cause of cancer death worldwide. More than half of the world's population is infected, making universal eradication impractical. Clinical trials suggest that antibiotic treatment only reduces gastric cancer risk in patients with non-atrophic gastritis (NAG), and is ineffective once preneoplastic lesions of multifocal atrophic gastritis (MAG) and intestinal metaplasia (IM) have occurred. Therefore, additional strategies for risk stratification and chemoprevention of gastric cancer are needed. We have implicated polyamines, generated by the rate-limiting enzyme ornithine decarboxylase (ODC), in gastric carcinogenesis. During H. pylori infection, the enzyme spermine oxidase (SMOX) is induced, which generates hydrogen peroxide from the catabolism of the polyamine spermine. Herein, we assessed the role of SMOX in the increased gastric cancer risk in Colombia associated with the Andean mountain region when compared with the low-risk region on the Pacific coast. When cocultured with gastric epithelial cells, clinical strains of H. pylori from the high-risk region induced more SMOX expression and oxidative DNA damage, and less apoptosis than low-risk strains. These findings were not attributable to differences in the cytotoxin-associated gene A oncoprotein. Gastric tissues from subjects from the high-risk region exhibited greater levels of SMOX and oxidative DNA damage by immunohistochemistry and flow cytometry, and this occurred in NAG, MAG and IM. In Mongolian gerbils, a prototype colonizing strain from the high-risk region induced more SMOX, DNA damage, dysplasia and adenocarcinoma than a colonizing strain from the low-risk region. Treatment of gerbils with either α-difluoromethylornithine, an inhibitor of ODC, or MDL 72527 (N(1),N(4)-Di(buta-2,3-dien-1-yl)butane-1,4-diamine dihydrochloride), an inhibitor of SMOX, reduced gastric dysplasia and carcinoma, as well as apoptosis-resistant cells with DNA damage. These data indicate that aberrant activation of polyamine-driven oxidative stress is a marker of gastric cancer risk and a target for chemoprevention.

[Recidivant laryngeal leishmaniasis: an unusual case in an immunocompetent patient treated with corticosteroids]. / Leishmaniosis laríngea recidivante: un caso inusual en un paciente inmunocompetente tratado con corticoides.

Leishmaniosis is a chronic parasitic disease, which in Argentina is mainly caused by protozoa belonging to the Leishmania (Viannia) braziliensis complex, leading to cutaneous and mucosal pathologies. We report a rare case of laryngeal leishmaniosis in a 29 year-old man from Jujuy province, Argentina, who had been misdiagnosed with other pathologies, carrying this infectious disease for about 20 years. During 2008, the patient was admitted with complaints of progressive hoarseness of the voice and dyspnea. He also reported having received tuberculostatics, antifungal and corticosteroids treatments since 2002. Different biopsies and direct laryngoscopic exams revealed inespecific granulomatous larynx, TBC-related laryngitis, laryngitis related to Histoplasma infection, extra-nodal Natural Killer-cell lymphoma. Finally, the patient was evaluated at the University Hospital and the final diagnosis was: granulomatous larynx, intra and extra-cytoplasmic Leishmania spp amastigotes, negative for TBC and Histoplasma cultures, and chronic laryngitis related to Leishmania infection, according to the laryngeal endoscopy, microbiological and histopathological exams, respectively. The patient received pentavalent antimonial treatment and his condition improved after 2 months of follow-up. Primary laryngeal leishmaniosis is rare and this localization does not belong to the most prevalent mucosal leishmaniosis. However, this parasitic disease warrants special concern, especially in patients who received prolonged corticosteroid treatments, in order to avoid a misdiagnosis of this disease.

[Strongyloides stercoralis and HIV: a case report of an indigenous disseminated infection from non-endemic area]. / Strongyloides stercoralis y VIH: un caso de infección diseminada en una zona no endémica.

Strongyloides stercoralis affects people who live in the tropics, but it also extends to temperate regions where its low incidence rate may lead to misdiagnose it. Inside the host this nematode may remain silent for many years, nevertheless, in patients infected with HIV its reactivation leads to a disseminated infection in ectopic sites. This report presents the case of a 34 years-old man infected with HIV who lived in a highland area in the province of Córdoba, Argentina. He was admitted to the hospital because of a complicated Pneumocystis jiroveci pneumonia, receiving trimethoprim-sulfamethoxazole and prednisone treatment. A few days after admission his conditions deteriorated badly, a sputum examination revealed filariform larvae of S. stercoralis, he was then given oral ivermectin medication (200 microg/kg/d). Malabsorption and ileus were installed and he died from multiorganic failure. The evolution of HIV infection to AIDS, a steroids treatment and therapy failure despite oral ivermectin triggered larvae proliferation and lead to disseminated hyperinfection until he died. This report presents not only the first case of disseminated strongyloidiasis detected in our Hospital but also an indigenous infection acquired in a non-endemic area. An awareness of an increased predisposition to this infection, especially in immunocompromised patients with malabsorption and ileus is of paramount importance, since failure to initiate appropriate therapy can lead to catastrophic outcomes, as illustrated in this case report.

[Survival of Trichomonas vaginalis in the environmental media]. / Supervivencia de Trichomonas vaginalis en el medio ambiente.

The survival of Trichomonas vaginalis outside of the body and from culture media was evaluated under environmental conditions using adsorbent (towels) and non adsorbent (plastic wells) surfaces. After 120 min of exposition under external conditions recovery of parasites from clinical samples showed viable protozoa onto adsorbent and non adsorbent surfaces (5.1% and 30.5%, respectively), as well as for parasites harvested from culture media and assayed onto both surfaces (77.2% and 81.8%, respectively). Parasites from human samples and culture could survive up to 24 h only onto non adsorbent materials (5.1% and 9.1%, respectively). Ability of T. vaginalis to remain viable under external conditions is discussed in relation to its non venereal transmission.

Supervivencia de Trichomonas vaginalis en el medio ambiente / Survival of Trichomonas vaginalis under environmental conditions

La supervivencia de Trichomonas vaginalis fuera del cuerpo humano y a partir de medios de cultivo, se evaluó en condiciones ambientales sobre soportes absorbentes (trozos de toallas) y no absorbentes (cubetas de plástico). Hasta 120 min de la exposición en el medio externo, se recuperaron protozoarios viables ensayados sobre materiales absorbentes y no absorbentes, tanto de muestras clínicas (5,1 por ciento y 30,5 por ciento, respectivamente) como de medios de cultivo ensayados sobre ambas superficies (77,2 por ciento y 81,8 por ciento, respectivamente). Los parásitos contenidos en materiales biológicos y de cultivo que se ensayaron sobre superficies no absorbentes resultaron los únicos que se recuperaron luego de 24 h (5,1 por ciento y 9,1 por ciento, respectivamente). La capacidad de T.vaginalis de conservar la viabilidad en condiciones externas se discute en relación con su transmisión no venérea.

Supervivencia de Trichomonas vaginalis en el medio ambiente / Survival of Trichomonas vaginalis under environmental conditions

La supervivencia de Trichomonas vaginalis fuera del cuerpo humano y a partir de medios de cultivo, se evaluó en condiciones ambientales sobre soportes absorbentes (trozos de toallas) y no absorbentes (cubetas de plástico). Hasta 120 min de la exposición en el medio externo, se recuperaron protozoarios viables ensayados sobre materiales absorbentes y no absorbentes, tanto de muestras clínicas (5,1 por ciento y 30,5 por ciento, respectivamente) como de medios de cultivo ensayados sobre ambas superficies (77,2 por ciento y 81,8 por ciento, respectivamente). Los parásitos contenidos en materiales biológicos y de cultivo que se ensayaron sobre superficies no absorbentes resultaron los únicos que se recuperaron luego de 24 h (5,1 por ciento y 9,1 por ciento, respectivamente). La capacidad de T.vaginalis de conservar la viabilidad en condiciones externas se discute en relación con su transmisión no venérea. (AU)

Supervivencia de Trichomonas vaginalis en el medio ambiente. / [Survival of Trichomonas vaginalis in the environmental media]

The survival of Trichomonas vaginalis outside of the body and from culture media was evaluated under environmental conditions using adsorbent (towels) and non adsorbent (plastic wells) surfaces. After 120 min of exposition under external conditions recovery of parasites from clinical samples showed viable protozoa onto adsorbent and non adsorbent surfaces (5.1

and 30.5

, respectively), as well as for parasites harvested from culture media and assayed onto both surfaces (77.2

and 81.8

, respectively). Parasites from human samples and culture could survive up to 24 h only onto non adsorbent materials (5.1

and 9.1

, respectively). Ability of T. vaginalis to remain viable under external conditions is discussed in relation to its non venereal transmission.

Detection of picobirnavirus in HIV-infected patients with diarrhea in Argentina.

Diarrhea due to enteric pathogens is an important complication of advanced HIV infection. Picobirnaviruses are agents recently linked with human enteritis. In total, 197 fecal samples collected from HIV-infected and noninfected patients with and without diarrhea were investigated for the presence of rotavirus and picobirnavirus by polyacrylamide gel electrophoresis. Picobirnavirus was detected in 8.8% of 57 HIV-infected patients with diarrhea, but it was detected in neither those without diarrhea (p<.018) nor in the group of subjects uninfected with HIV (p<.022). All genomic electropherotypes of picobirnavirus strains had a wide pattern. Picobirnavirus genome segments varied in size between 2.4 and 2.7 and 1.6 and 1.9 kbp for the slow and fast migrating bands, respectively. Rotaviruses were not detected in any of the clinical groups studied. Two methods for the extraction of nucleic acid-phenol/chloroform and guanidinium thiocynate (GTC)/silica-were compared. Detection of picobirnavirus by polyacrylamide gel electrophoresis was 2.5 times more sensitive following guanidinium thiocynate RNA extraction. This investigation offers preliminary results about the circulation of picobirnavirus in HIV-infected patients in Córdoba, Argentina.

PIP: In 1988, a new group of viruses containing a bisegmented double-stranded RNA genome was described and named "picobirnavirus" (PBV). Viruses with similar properties have subsequently been found in fecal specimens collected from HIV-infected and noninfected patients with gastrointestinal symptoms in several countries. The present study used polyacrylamide gel electrophoresis (PAGE) to examine fecal specimens from 197 HIV infected and noninfected adults, with and without diarrhea, from Cordoba, Argentina, for rotavirus and PBV. PBVs were detected in the stools of 5 HIV-infected patients with diarrhea (8.8%), but in none of the other subgroups (HIV-positive patients without diarrhea, HIV-negative patients with diarrhea, HIV-negative patients without diarrhea). 3 of the 5 stool samples positive for PBV were also positive for intestinal parasites (mixed infection), but these parasites were found with equal frequency in HIV-infected patients without diarrhea. Rotaviruses were not detected in any of the subgroups. PBV genome segments varied in size between 2.4-2.7 and 1.6-1.9 kbp for the slow and fast migrating bands, respectively. PBV detection by the PAGE technique was 2.5 times more sensitive after guanidinium thiocyanate RNA extraction. Further research is required to determine the duration of excretion of PBVs in HIV-infected patients with diarrhea and understand the immune response to infection.

[Single dose of fleroxacin for the treatment of adult acute diarrhea]. / Monodosis de fleroxacina para el tratamiento de la diarrea aguda estival en el adulto.

The purpose of this work was to evaluate the efficacy and safety of a single dose of 400 mg of fleroxacin for the empiric antibiotic treatment of acute diarrhea in adult patients. A prospective, double-blind, placebo-controlled, randomized trial was designed. All the adult patients who consulted in our hospital for acute diarrhea from December 1994 to April 1995 were included. 72 patients were randomized to receive a single dose of fleroxacin 400 mg and 73 were placebo. Thirty-eight patients in each group were evaluable for efficacy. Between both groups there were not statistically significant differences in age, sex, number of loose stools per day at inclusion, days since the onset of symptoms up to inclusion, other symptoms than diarrhea at inclusion, percentages of bacterial pathogens and parasites isolated and symptomatic treatment indicated. At the third day since inclusion, clinical cure occurred in 72.2% of the patients receiving fleroxacin, compared with 36.4% of those receiving placebo; p = 0.002. The mean +/- SD time to cure was 2.2 +/- 1.2 days in the fleroxacin group and 3.2 +/- 2.0 days in the placebo group; p = 0.01. Twenty-eight and 16.7% of patients reported adverse effects in the fleroxacin and placebo groups respectively; p = 0.3. It is concluded that a single dose of fleroxacin 400 mg is an effective and safe alternative for the empiric antibiotic treatment of acute diarrhea in adults.

Amebas patógenas de vida libre / Pathogenic free living amebas

Las pequeñas amebas de vida libre están ampliamente distribuidas en todo el mundo en continuo contacto con el hombre y animales; sus formas quísticas son capaces de sobrevivir en el suelo, aire y agua. Las infecciones causadas por las mismas han tomado en los últimos treinta años notable importancia médica ya que muchos casos fatales no fueron diagnosticados clínicamente ni por el laboratorio, debido al desconocimiento de la potencial capacidad patogénica de estas amebas. Hoy se sabe que la meningoencefalitis amebiana primaria (MAP) causada por Naegleria fowleri y la encefalitits amebiana granulomatosa (EAG) originada por especies de Acanthamoeba spp se han incrementado en el mundo tanto en sujetos sanos como en inmunocomprometidos, incluyendo muchos individuos con SIDA. El grupo más reciente de infecciones causadas por especies del género Acanthamoeba es la queratitis amebiana relacionada principalmente con la falta de cuidado en el mantenimiento de las lentes de contacto. La terapia de la queratitis es problemática debido a la presencia de quistes en los tejidos, y aunque se han informado algunas curas de pacientes, la terapéutica médica aún constituye un capítulo no resuelto

Amebas patógenas de vida libre / Pathogenic free living amebas

Las pequeñas amebas de vida libre están ampliamente distribuidas en todo el mundo en continuo contacto con el hombre y animales; sus formas quísticas son capaces de sobrevivir en el suelo, aire y agua. Las infecciones causadas por las mismas han tomado en los últimos treinta años notable importancia médica ya que muchos casos fatales no fueron diagnosticados clínicamente ni por el laboratorio, debido al desconocimiento de la potencial capacidad patogénica de estas amebas. Hoy se sabe que la meningoencefalitis amebiana primaria (MAP) causada por Naegleria fowleri y la encefalitits amebiana granulomatosa (EAG) originada por especies de Acanthamoeba spp se han incrementado en el mundo tanto en sujetos sanos como en inmunocomprometidos, incluyendo muchos individuos con SIDA. El grupo más reciente de infecciones causadas por especies del género Acanthamoeba es la queratitis amebiana relacionada principalmente con la falta de cuidado en el mantenimiento de las lentes de contacto. La terapia de la queratitis es problemática debido a la presencia de quistes en los tejidos, y aunque se han informado algunas curas de pacientes, la terapéutica médica aún constituye un capítulo no resuelto (AU)