Relationship between enterotoxigenic Escherichia coli and travelers' diarrhea in Mexico, from 1992 to 1997

The purpose of this study was to examine the relationship between enterotoxigenic ETEC and travelers' diarrhea over a period of five years in Guadalajara, Mexico. Specifically, this study identified and characterized ETEC from travelers with diarrhea. The objectives were to study the colonization factor antigens, toxins and antibiotic sensitivity patterns in ETEC from 1992 to 1997 and to study the molecular epidemiology of ETEC by plasmid content and DNA restriction fragment patterns. ^ In this survey of travelers' diarrhea in Guadalajara, Mexico, 928 travelers with diarrhea were screened for enteric pathogens between 1992 and 1997. ETEC were isolated in 195 (19.9%) of the patients, representing the most frequent enteric pathogen identified. ^ A total of 31 antimicrobial susceptibility patterns were identified among ETEC isolates over the five-year period. ^ The 195 ETEC isolates contained two to six plasmids each, which ranged in size from 2.0 to 23 kbp. ^ Three different reproducible rRNA gene restriction patterns (ribotypes R-1 to R-3) were obtained among the 195 isolates with the enzyme, HindIII. ^ Colonization factor antigens (CFAs) were identified in 99 (51%) of the 195 ETEC strains studied. ^ Cluster analysis of the observations seen in the four assays all confirmed the five distinct groups of study-year strains of ETEC. Each group had a >95% similarity level of strains within the group and <60% similarity level between the groups. In addition, discriminant analysis of assay variables used in predicting the ETEC strains, reveal a >80% relationship between both the plasmid and rRNA content of ETEC strains and study-year. ^ These findings, based on laboratory observations of the differences in biochemical, antimicrobial susceptibility, plasmid and ribotype content, suggest complex epidemiology for ETEC strains in a population with travelers' diarrhea. The findings of this study may have implications for our understanding of the epidemiology, transmission, treatment, control and prevention of the disease. It has been suggested that an ETEC vaccine for humans should contain the most prevalent CFAs. Therefore, it is important to know the prevalence of these factors in ETEC in various geographical areas. ^ CFAs described in this dissertation may be used in different epidemiological studies in which the prevalence of CFAs and other properties on ETEC will be evaluated. Furthermore, in spite of an intense search in near 200 ETEC isolates for strains that may have clonal relationship, we failed to identify such strains. However, further studies are in progress to construct suitable live vaccine strains and to introduce several of CFAs in the same host organism by recombinant DNA techniques (Dr. Ann-Mari Svennerholm's lab). (Abstract shortened by UMI.)^

Persisting abdominal symptoms after travelers' diarrhea: Is there a genetic predisposition?

Functional gastrointestinal disorders (FGIDs) are defined as ailments of the mid or lower gastrointestinal tract which are not attributable to any discernable anatomic or biochemical defects.1 FGIDs include functional bowel disorders, also known as persisting abdominal symptoms (PAS). Irritable bowel syndrome (IBS) is one of the most common illnesses classified under PAS.2,3 This is the first prospective study that looks at the etiology and pathogenesis of post-infectious PAS in the context of environmental exposure and genetic susceptibility in a cohort of US travelers to Mexico. Our objective was to identify infectious, genetic and environmental factors that predispose to post infectious PAS. ^ Methods. This is a secondary data analysis of a prospective study on a cohort of 704 healthy North American tourists to Cuernavaca, Morelos and Guadalajara, Jalisco in Mexico. The subjects at risk for Travelers' diarrhea were assessed for chronic abdominal symptoms on enrollment and six months after the return to the US. ^ Outcomes. PAS was defined as disturbances of mid and lower gastrointestinal system without any known pathological or radiological abnormalities, or infectious, or metabolic causes. It refers to functional bowel disease, category C of functional gastrointestinal diseases as defined by the Rome II criterion. PAS was sub classified into Irritable bowel syndrome (IBS) and functional abdominal disease (FAD). ^ IBS is defined as recurrent abdominal pain or discomfort present at least 25% and associated with improvement with defecation, change in frequency and form of stool. FAD encompasses other abdominal symptoms of chronic nature that do not meet the criteria for IBS. It includes functional diarrhea, functional constipation, functional bloating: and unspecified bowel symptoms. ^ Results. Among the 704 travelers studied, there were 202 cases of PAS. The PAS cases included 175 cases of FAD and 27 cases of IBS. PAS was more frequent among subjects who developed traveler's diarrhea in Mexico compared to travelers who remained healthy during the short term visit to Mexico (52 vs. 38; OR = 1.8; CI, 1.3–2.5, P < 0.001). A statistically significant difference was noted in the mean age of subjects with PAS compared to healthy controls (28 vs. 34 yrs; OR = 0.97, CI, 0.95–0.98; P < 0.001). Travelers who experienced multiple episodes, a later onset of diarrhea in Mexico and passed greater numbers of unformed stools were more likely to be identified in PAS group at six months. Participants who developed TD caused by enterotoxigenic E.coli in Mexico showed a 2.6 times higher risk of developing FAD (P = 0.003). Infection with Providencia ssp. also demonstrated a greater risk to developing PAS. Subjects who sought treatment for diarrhea while in Mexico also displayed a significantly lower frequency of IBS at six months follow up (OR = 0.30; CI, 0.10–0.80; P = 0.02). ^ Forty six SNPs belonging to 14 genes were studied. Seven SNPs were associated with PAS at 6 months. These included four SNPs from the Caspase Recruitment Domain-Containing Protein 15 gene (CARD15), two SNPs from Surfactant Pulmonary-Associated Protein D gene (SFTPD) and one from Decay-Accelerating Factor For Complement gene (CD55). A genetic risk score (GRS) was composed based on the 7 SNPs that showed significant association with PAS. A 20% greater risk for PAS was noted for every unit increase in GRS. The risk increased by 30% for IBS. The mean GRS was high for IBS (2.2) and PAS (1.1) compared to healthy controls (0.51). These data suggests a role for these genetic polymorphisms in defining the susceptibility to PAS. ^ Conclusions. The study allows us to identify individuals at risk for developing post infectious IBS (PI-IBS) and persisting abdominal symptoms after an episode of TD. The observations in this study will be of use in developing measures to prevent and treat post-infectious irritable bowel syndrome among travelers including pre-travel counseling, the use of vaccines, antibiotic prophylaxis or the initiation of early antimicrobial therapy. This study also provides insights into the pathogenesis of post infectious PAS and IBS. (Abstract shortened by UMI.)^

Susceptibility to travelers' diarrhea and histo-blood group antigens

Histo-blood group antigens (HBGAs) have been associated with susceptibility to enteric pathogens including noroviruses (NoVs), enterotoxigenic Escherichia coli (ETEC), Campylobacter jejuni, and Vibrio cholerae. We performed a retrospective cohort study to evaluate the relationship between traveler HBGA phenotypes and susceptibility to travelers' diarrhea (TD) and post-infectious complications. 364 travelers to Guadalajara, Mexico were followed prospectively from June 1 - September 30, 2007 and from June 7–July 28, 2008 for the development of TD and at 6 months for post-infectious irritable bowel syndrome (PIIBS). Noroviruses were detected from illness stool specimens with RT-PCR. Diarrheal stool samples were also assayed for enterotoxigenic and enteroaggregative E. coli, Salmonella species, Shigella species, Vibrio species, Campylobacter jejuni, Yersinia enterocolitica, Aeromonas species, and Plesiomonas species. Diarrheal stools were evaluated for inflammation with fecal leukocytes, mucus, and occult blood. Phenotyping for ABO and Lewis antigens with an ELISA assay and FUT2 gene PCR genotyping for secretor status were performed with saliva. 171 of 364 (47%) subjects developed TD. HBGA typing for the travelers revealed O (62.9%), A (34.6%), B (1.6%), and AB (0.8%) phenotypes. There were 7% nonsecretors and 93% secretors among the travelers. AB phenotypes were more commonly associated with Cryptosporidium species (P=0.04) and ETEC ( P=0.08) as causes of TD. AB and B phenotype individuals were more likely to experience inflammatory diarrhea, particularly mucoid diarrhea ( P=0.02). However, there were relatively few individuals with AB and B phenotypes. GI and GII NoV and Cryptosporidium species infections and PI-IBS were identified only in secretors, but these differences were not statistically significant, (P=1.00), (P=1.00), and (P=0.60), respectively. Additional studies are needed to evaluate whether AB phenotype individuals may be more susceptible to developing TD associated with Cryptosporidium species or ETEC, and whether AB and B phenotype individuals may be more likely to develop inflammatory TD. Further studies are needed to investigate whether nonsecretor travelers may be at less risk for developing infections with NoVs and Cryptosporidium species and PI-IBS.^

Natural history of placebo treatment in adults acquiring travelers' diarrhea in Mexico

The natural history of placebo treated travelers' diarrhea and the prognostic factors of recovery from diarrhea were evaluated using 9 groups of placebo treated subjects from 9 clinical trial studies conducted since 1975, for use as a historical control in the future clinical trial of antidiarrheal agents. All of these studies were done by the same group of investigators in one site (Guadalajara, Mexico). The studies are similar in terms of population, measured parameters, microbiologic identification of enteropathogens and definitions of parameters. The studies had two different durations of followup. In some studies, subjects were followed for two days, and in some they were followed for five days.^ Using definitions established by the Infectious Diseases society of America and the Food and Drug Administration, the following efficacy parameters were evaluated: Time to last unformed stool (TLUS), number of unformed stools post-initiation of placebo treatment for five consecutive days of followup, microbiologic cure, and improvement of diarrhea. Among the groups that were followed for five days, the mean TLUS ranged from 59.1 to 83.5 hours. Fifty percent to 78% had diarrhea lasting more than 48 hours and 25% had diarrhea more than five days. The mean number of unformed stools passed on the first day post-initiation of therapy ranged from 3.6 to 5.8 and, for the fifth day ranged from 0.5 to 1.5. By the end of followup, diarrhea improved in 82.6% to 90% of the subjects. Subjects with enterotoxigenic E. coli had 21.6% to 90.0% microbiologic cure; and subjects with shigella species experienced 14.3% to 60.0% microbiologic cure.^ In evaluating the prognostic factors of recovery from diarrhea (primary efficacy parameter in evaluating the efficacy of antidiarrheal agents against travelers' diarrhea). The subjects from five studies were pooled and the Cox proportional hazard model was used to evaluate the predictors of prolonged diarrhea. After adjusting for design characteristics of each trial, fever with a rate ratio (RR) of 0.40, presence of invasive pathogens with a RR of 0.41, presence of severe abdominal pain and cramps with a RR of 0.50, number of watery stools more than five with a RR of 0.60, and presence of non-invasive pathogens with a RR of 0.84 predicted a longer duration of diarrhea. Severe vomiting with a RR of 2.53 predicted a shorter duration of diarrhea. The number of soft stools, presence of fecal leukocytes, presence of nausea, and duration of diarrhea before enrollment were not associated with duration of diarrhea. ^

Atentique´s environmental and economic development shrinkage in globlalization era

This paper focuses on the effects the transfer of ownership from a state‐owned Paper Mill Company to a corporate private ownership has had on environmental and economic shrinkage in Atenquique. This transfer was the result of the ongoing economic process of globalization, after the industrial boom of the paper mills during the second half of the last century. The paper also focuses on how the employees of this Paper Mill Company live and how they have been affected by globalization and how they feel about their paper mill’s new corporate owners. The methodology used was descriptive and exploratory. A sample of ten workers at the company who lived in Atenquique was chosen for an interview. After being inhabited the town of Atenquique developed in terms of population, society and economy. On the other hand the Industrial Company of Atenquique grew during the period when it was a property of the Mexican State. After the company’s privatization, the town started to decline and shrink in three above‐mentioned variables. The impact on the environmental and economic development has initiated the shrinking and declining of Atenquique and the surrounding cities and towns.

Cooperación y conflicto entre empresas, comunidades y gobierno : nuevos movimientos sociales en el caso de Cerro de San Pedro, México

El objetivo de este trabajo es analizar las relaciones de cooperación y conflicto entre una compañía minera y las comunidades, los Nuevos Movimientos Sociales y los tres niveles de gobierno involucrados. La compañía Minera inició operaciones para una mina a cielo abierto de oro y plata con el apoyo de los gobiernos locales, estatales y federal. Los habitantes de estas comunidades apoyados por grupos ambientalistas y Organizaciones No Gubernamentales argumentan que el proyecto contamina las Fuentes de agua fresca además de perturbar el medio ambiente y la ecología de la región. La metodología empleada consistió en un análisis histórico social para determinar, en un estudio exploratorio, las principales variables económicas, políticas, legales, sociales y culturales que inciden en el caso, sobre todo después de la firma del Tratado de Libre Comercio de América del Norte. Los hallazgos de esta investigación contribuyen a explicar las relaciones de cooperación y conflicto entre las empresas multinacionales que operan en las comunidades, a analizar el rol del gobierno en sus tres niveles y de los nuevos movimientos sociales en la conformación de las economías locales bajo procesos de integración económica regional. Los resultados también son de relevancia por sus contribuciones para el entendimiento de procesos de responsabilidad social corporativa de las empresas transnacionales y los procesos de contestación y acción colectiva de los nuevos movimientos sociales en el desarrollo económico y ambiental de las comunidades locales.

I Encuentro Nacional de Pensamiento Latinoamericano

Fil: Jalif de Bertranou, Clara Alicia. Universidad Nacional de Cuyo. Facultad de Filosofía y Letras

Conidial germination of Botryosphaeria dothidea Mough.: Fr (Ces. & De Not.) and histological alterations on stems of pitahaya (Hylocereus undatus H.) (Haworth) Britton & Rose

Conidial germination of Botryosphaeria dothidea (anamorph: Fusicoccum) in sterile distilled water and 1% sterile dextrose solution was evaluated at 4, 6, 12, 24 and 36 h after incubation. Also, it was described the anatomical changes on pitahaya stems induced by this fungus, collected in the field and artificially inoculated in the laboratory. Conidial germination was less than 30% in water and it was improved when 1% dextrose was added to the water. In 1% dextrose solution the germination was 90% after 4h of incubation and 100% at 6 h. Pathogen germ tubes had entered through wounds and sometimes through stomata and hyphae colonized intra and intercellularly in the parenchyma-chlorenchyma tissues. On naturally and artificially diseased stems the main alterations were: destruction of cuticle, hyperplasia of epidermal and collenchymatous hypodermal cells and conform the advance of the pathogen a layer of lignified periderm was formed surrounding the damaged tissues; however, it couldn't stop the advance of the pathogen and the cells that surrounded the lesion suffered necrosis.

Manipulación de la crisis a través de la acumulación por desposesión en México

La acumulación por desposesión es un ejercicio de poder que se ha expresado en el devenir histórico del capitalismo, aunque la acumulación por desposesión, cobra fuerza ideológica a partir del modelo neoliberal y representa, sino la única forma, si la más importante actualmente para sostener o incrementar la acumulación de capital en la geografía glocal (lograr el establishment del sistema bancario y de las grandes corporaciones y centros de poder -BM-FMI y BCE). El rasgo económico-político que definiría dicha acumulación por desposesión, es que su instrumentación para llevarse a cabo, necesita obligatoriamente que el Estado y los dueños de capital (productivo, comercial, financiero) tengan el interés común “contubernio" de que los espacios receptores sirvan para que el capital incremente su capital; esto sólo se logra expropiando el derecho del trabajador de vivir dignamente con un empleo bien remunerado. En palabras de David Harvey (2003, 2004, 2204b, 2007a, 2007b 2007c) quien posibilita la acumulación por desposesión es la liberación de un conjunto de activos, incluida la fuerza de trabajo a un coste muy bajo y en algunos casos, nulo.

Práctica-ritual Búsqueda de Visión en México : Construyendo (nos) la sexualidad y tomando posturas particulares respecto del cuerpo

En mi búsqueda acerca del tema de sexualidad, más allá de la visión del Estado nacional, los discursos desde la medicina, los medios de comunicación y el contexto religioso, encontré un espacio no hegemónico de educación, un espacio que se inserta en una "espiritual red"; el ejemplo de la espiritual que abordaré, es la neoindianidad, donde el sincretismo y lo híbrido surge a partir de la fusión de corrientes filosóficas y espirituales. Se pretende relatar parte de la experiencia y (re)significado de la sexualidad de hombres y mujeres a partir de las concepciones y discursos de las "abuelas" que dirigieron la práctica-ritual en Guadalajara, México. Ya quela escuela no es el único espacio para formar identidad sexual y concepciones de formas vivibles de la sexualidad, ¿cómo se construye el cuerpo en contextos de múltiples tradiciones religiosas, manifestaciones y diversos saberes? Por otro lado se proyecta hablar de la perspectiva emocional, espiritual y religiosa reconfigurada, desde donde se aborda el tema de lo sagrado femenino y masculino en la búsqueda de visión, que implica a las mujeres y hombres la toma de conciencia particular acerca de sus cuerpos y sexualidad

Viajes, exilio y memoria en Milenio de Manuel Vázquez Montalbán

Algunas de las novelas de la saga Carvalho de Manuel Vázquez Montalbán (Asesinato en el comité central, Los Mares del Sur, El Balneario, Milenio) son particularmente interesantes para rastrear las tensiones que en las sociedades contemporáneas se registran en torno a la memoria y el olvido: ¿qué recordar y qué olvidar? parecen ser preguntas decisivas para el trazado de proyectos políticos y culturales que permitan a unos y otros convivir en la posmodernidad. En estos textos, la recuperación de la memoria aparece ligada en numerosas ocasiones a experiencias de viajes y exilio. Los viajeros de Vázquez Montalbán nunca son turistas, fieles a la consigna de Bowles, sólo saben dónde y cuándo empieza su viaje, nunca cuando termina. En Milenio esta conjunción viaje-memoria es el eje del relato, los personajes recorren el mundo y se encuentran en diferentes escenarios que son delineados con unos pocos trazos necesariamente gruesos, entre ellos los referentes a la historia y el pasado local. Lejos de conformar una postal remota, estas referencias configuran una red de factores que condicionan las vidas de quienes los transitan porque los recuerdos están enraizados en un lugar, y el espacio se convierte en tiempo y memoria cristalizados. En la novela todos los personajes están en movimiento, pasajeros en tránsito, unos y otros ofrecen sus propios relatos acerca de los hechos del pasado y el presente. Milenio resulta así una especie de balance (definitivamente el último de Vázquez Montalbán) de la memoria y la historia del mundo globalizado.

Práctica-ritual Búsqueda de Visión en México : Construyendo (nos) la sexualidad y tomando posturas particulares respecto del cuerpo

En mi búsqueda acerca del tema de sexualidad, más allá de la visión del Estado nacional, los discursos desde la medicina, los medios de comunicación y el contexto religioso, encontré un espacio no hegemónico de educación, un espacio que se inserta en una "espiritual red"; el ejemplo de la espiritual que abordaré, es la neoindianidad, donde el sincretismo y lo híbrido surge a partir de la fusión de corrientes filosóficas y espirituales. Se pretende relatar parte de la experiencia y (re)significado de la sexualidad de hombres y mujeres a partir de las concepciones y discursos de las "abuelas" que dirigieron la práctica-ritual en Guadalajara, México. Ya quela escuela no es el único espacio para formar identidad sexual y concepciones de formas vivibles de la sexualidad, ¿cómo se construye el cuerpo en contextos de múltiples tradiciones religiosas, manifestaciones y diversos saberes? Por otro lado se proyecta hablar de la perspectiva emocional, espiritual y religiosa reconfigurada, desde donde se aborda el tema de lo sagrado femenino y masculino en la búsqueda de visión, que implica a las mujeres y hombres la toma de conciencia particular acerca de sus cuerpos y sexualidad

Viajes, exilio y memoria en Milenio de Manuel Vázquez Montalbán

Algunas de las novelas de la saga Carvalho de Manuel Vázquez Montalbán (Asesinato en el comité central, Los Mares del Sur, El Balneario, Milenio) son particularmente interesantes para rastrear las tensiones que en las sociedades contemporáneas se registran en torno a la memoria y el olvido: ¿qué recordar y qué olvidar? parecen ser preguntas decisivas para el trazado de proyectos políticos y culturales que permitan a unos y otros convivir en la posmodernidad. En estos textos, la recuperación de la memoria aparece ligada en numerosas ocasiones a experiencias de viajes y exilio. Los viajeros de Vázquez Montalbán nunca son turistas, fieles a la consigna de Bowles, sólo saben dónde y cuándo empieza su viaje, nunca cuando termina. En Milenio esta conjunción viaje-memoria es el eje del relato, los personajes recorren el mundo y se encuentran en diferentes escenarios que son delineados con unos pocos trazos necesariamente gruesos, entre ellos los referentes a la historia y el pasado local. Lejos de conformar una postal remota, estas referencias configuran una red de factores que condicionan las vidas de quienes los transitan porque los recuerdos están enraizados en un lugar, y el espacio se convierte en tiempo y memoria cristalizados. En la novela todos los personajes están en movimiento, pasajeros en tránsito, unos y otros ofrecen sus propios relatos acerca de los hechos del pasado y el presente. Milenio resulta así una especie de balance (definitivamente el último de Vázquez Montalbán) de la memoria y la historia del mundo globalizado.