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Salmonella Enteritidis is the main cause of foodborne salmonellosis worldwide. The limited effectiveness of current interventions against this pathogen has been the main incentive to develop new methods for the efficient control of this infection. To investigate the use of DNA vaccines against S. Enteritidis in humans, immune responses stimulated by two plasmids containing the genes designated SEN1002, located in the pathogenicity island SPI-19 and encoding a Hcp protein involved in transport mechanisms, and SEN1395, located in the genomic island ΦSE14 and encoding a protein of a new superfamily of lysozymes, were evaluated. Humoral and cellular responses following intranasal immunization of two groups of BALB/c mice with the plasmids pV1002 and pV1395 plus adjuvant were evaluated and it was observed that the IgG2a/IgG1 ratios were sixfold higher than control groups. Both plasmids stimulated specific secretory IgA production. Increased proliferation of lymphocytes and IFN-γ production were detected in both experimental groups. DNA-vaccinated mice developed protective immunity against a virulent strain of S. Enteritidis, with nearly 2 logs of protection level compared to the negative control values in the spleen. Therefore, DNA vaccines are efficient at stimulating cellular and humoral immune responses at systemic and mucosal levels.

Objective: intervene a workline throughout ergonomic approach to diminish incidence of Carpal Tunnel Syndrome (CTS)., Methods and Materials: an ergonomic intervention study was developed in workstations with highest index of musculoskeletal disorder (MED) associated to cumulative trauma. The Deparis method, Reba and Ocra check list methods were used, also morbility reviewes. National and international ethics criteria were carried out., Results: workers identified 3 fundamental issues using the Deparis method: repetitive activities, postures adopted and uncomfortable furniture. The analysis of the workstation with Reba and Ocra methods before the changes, evidenciated that 56% of postures adopted were high risk postures, the 44% remaining were medium and low-risk. Following the active pause program (APP), furniture changes and work rhythm decrease, was noted that the risk of suffering MED decreased. The morbility review, drop in consults of musculoskeletal system (MES) related to CTS observed. The APP was well accepted by women, but not initially men., Discussion: the research show that when the work rhythm decreases, the symptom of MES related to CTS have a remarkable decrease, also that changes in the furniture, generate great ergonomic differences and changes in the work environment are not possible if workers don't empower the tools to make-it.

Onchocerciasis is a chronic filarial infection transmitted by Simulium flies that has a focal geographical distribution in Latin America. The southern Venezuelan focus has a gradient of endemicity that includes the largest number of hyperendemic communities in the continent, many of them in remote forest and mountainous areas, where it is an important public health problem among the Yanomami indigenous population. The recent introduction of Geographical Information Systems (GIS) tools and a landscape epidemiology approach for study of vector borne diseases is helping to understand relationships between environment and transmission dynamics of onchocerciasis. Striking differences in the transmission dynamics of onchocerciasis between different river courses were detected. A significant relationship between onchocerciasis and temperature was also demonstrated. The geologic substrate, kind of landscape and vegetation seemed also to influence the transmission of onchocerciasis. In the Venezuelan Amazon, different kinds of landscapes associated with distinctive vector species, show different intensities of transmission of onchocerciasis. In this sense, landscape analysis aided by GIS, may prove to be a useful tool for better identification of the spatial distribution of onchocerciasis risk in the Orinoco basin.

Objective: To determine the intermediate-term outcome of 350-mm(2) Baerveldt glaucoma implants., Design: Retrospective, noncomparative case series., Participants: Sixty-five patients (65 eyes)., Intervention: Implantation of 350-mm(2) Baerveldt glaucoma drainage device., Main Outcome Measures: Intraocular pressure, number of glaucoma medications, best-corrected Snellen visual acuity, length of follow-up, risk factors for failure, and complications., Results: Mean intraocular pressure was reduced from a preoperative value of 32 mmHg to a 2-year postoperative value of 14 mmHg (56% reduction, P < 0.001). Success rates at 2-year follow-up were 71%, 81%, 78%, 60%, and 47% for the overall group, primary open-angle glaucoma group, neovascular group, uveitic group, and other group, respectively. After accounting for the effect of diagnosis group, significant risk factors in the overall group for failure at 2 years included younger age, high preoperative intraocular pressure, and more prior incisional surgeries. Glaucoma medication use in our overall study population was reduced from 2.5 mean preoperative medications to 0.8 postoperative medications (68%). Median change in Snellen visual acuity between preoperative and 2-year postoperative visits was not significant in the overall group. Postoperative complications included choroidal effusion in 15 patients (23%), tube obstruction by blood or vitreous in five patients (8%), phthisis in four patients (6%), aqueous misdirection in two patients (3%), strabismus in two patients (3%), tube-cornea touch in two patients (3%), endophthalmitis in two patients (3%), and retinal detachment in two patients (3%). No patients had suprachoroidal hemorrhage., Conclusions: The 350-mm(2) Baerveldt glaucoma implants are a safe and effective treatment for intermediate-term intraocular pressure control in patients with refractory glaucoma.

Primary school teachers in Québec suffer psychological distress, as shown by the Québec Health Survey (M. Gervais, 1993; Santè Québec, 1995). The authors applied and extended the French model (F. Guérin, A. Laville, F. Daniellou, J. Duraffourg, & A. Kerguelen, 1991) of analysis of work activity to observing classroom teaching (14 women in 10 classrooms for a total of 48 hr 24 min) to identify stressful elements. The authors observed a rapid sequence of actions, eye fixations of short duration, little physical or mental relaxation, multiple simultaneous activities, and uncomfortable temperature and humidity levels. Teachers use many strategies to teach, to create a learning environment, and to maintain attention in classrooms under adverse conditions. Examination of these strategies led to recommendations to improve relations between the teachers and their supervisors and to make the classroom an easier place to teach.

A questionnaire in Spanish (with yes/no answers) was developed in order to study effects of neurotoxic agents in groups of workers in Nicaragua. Since many workers in Latin America are illiterate, the questions were read to the subjects. The questionnaire initially contained 34 questions, which were reduced to 16 after studying whether the questions were interpreted in the intended way by the subjects, whether the answers were reasonably reproducible over a 3-week period, and whether the questions discriminated between groups exposed to different neurotoxic agents (mercury, lead, organic solvents, and organophosphate insecticides) and nonexposed groups. In total, 851 male workers in Nicaragua and Venezuela participated in the evaluation. The questionnaire is submitted for use in the monitoring of groups exposed to neurotoxic agents, particularly in Latin America. The authors welcome further evaluation.

To assess the applicability of the World Health Organization (WHO) Neurobehavioral Core Test Battery (NCTB), we evaluated 53 male and 29 female Venezuelan workers exposed to mixtures of organic solvents in an adhesive factory, and 56 male and 11 female workers unexposed to any type of neurotoxic chemical. The average age of unexposed workers was 30 years and 33 years for those exposed, average schooling for both groups was 8 years, and the mean duration of exposure was 7 years. The NCTB, which assesses central nervous system functions, is composed of seven tests that measure simple motor function, short-term memory, eye-hand coordination, affective behavior, and psychomotor perception and speed. The battery includes: profile of mood states (POMS); Simple Reaction Time for attention and response speed; Digit Span for auditory memory; Santa Ana manual dexterity; Digit-Symbol for perceptual motor speed; the Benton visual retention for visual perception and memory; and Pursuit Aiming II for motor steadiness. In each of 13 subtests, the exposed group had a poorer performance than the nonexposed group. The range of differences in mean performance was between 5% and 89%, particularly in POMS (tension-anxiety, anger-hostility, depression-rejection, fatigue-inertia, confusion-bewilderment), Simple Reaction Time, Digit-Symbol, and Santa Ana Pegboard (p < .05). In multivariate regression analyses, controlling for the effects of age, sex, and education, significantly poorer performance in the exposed was found for tension-anxiety, hostility, depression, and confusion moods in the POMS, and in digit-symbol and simple reaction time (p < .05). These alterations were also dose-related using years of exposure in analyses of covariance. Compared to the nonexposed, the exposed subjects demonstrated an increased frequency of subjective symptoms of fatigue, difficulties with memory, confusion, paresthesias in upper and lower extremities, and sleep disturbances. We conclude that the methodology is applicable to the population studied. The tests of the NCTB were accepted by the subjects and were administered satisfactorily, except for occasional difficulties in verbal comprehension in subtests of POMS, which is the only test that requires more demanding verbal skills. The magnitude of the behavioral deficits is consistent with the probable high level of exposure and with the range of deficits previously reported in workers with long-term solvent exposures.

Serum levels of tumor necrosis factor alpha/cachectin (TNF alpha) were studied in a group of adult patients with sickle cell disease (SCD), which include 31 patients with homozygous SS hemoglobinopathy and 10 patients bearing double heterozygous SC hemoglobinopathy and in their matched normal controls. All patients tested did not show any form of crisis for at least 4 weeks prior to the extraction of the sample. The amount of TNF alpha in serum was quantitated by means of an immunoenzymatic assay with a lower limit of detection of 25 pg/ml. The percentage of sera with detectable levels of TNF alpha was significantly increased in SCD patients as compared with the normal controls. Mean TNF alpha values in individuals with detectable levels of the cytokine were also significantly higher in the whole group of SCD patients and in patients bearing either SS or SC hemoglobinopathies than in the control group. An inverse correlation was observed between the percentages of Hb F and the levels of TNF alpha found in the sera from the patients.

To study the capacity of peripheral blood mononuclear cells (PBMC) from patients with sickle cell disease to synthesize antibodies in vitro, the levels of IgM, IgG, and IgA were quantitated in supernatants of cultured PBMC from a group of asymptomatic adults with sickle cell disease and from normal controls. The rates of spontaneous synthesis of IgM were similar in nonstimulated cultures of PBMC from patients and controls, whereas the amounts of IgG and IgA produced spontaneously by nonstimulated lymphocytes from the patients were significantly greater than those from controls. Similar levels of IgM, IgG, and IgA were detected in the supernatants of cultures stimulated with pokeweed mitogen from patients and controls. Thus, the capacity of PBMC to respond in vitro to pokeweed mitogen was preserved in the patients. The enhanced spontaneous synthesis of IgG and IgA suggests the presence of chronic polyclonal activation of B cells and/or defective regulation of the production of antibodies.

Mitogen induced lymphoproliferative responses and lymphocyte sub-populations were studied in a group of sickle cell disease (SCD) patients with homozygous SS hemoglobinopathy. Even though the response to a sub-optimal dose of Con A (0.5 microgram/ml of culture) was significantly decreased in patients with SCD, the proliferative responses to optimal doses of Con A, to PHA and to PWM were preserved in the patients. Addition of indomethacin to the cultures increased to a more significant degree the response to Con A of lymphocytes from patients than from the normal controls. Study of the mononuclear cell subsets indicated that the relative and absolute numbers of B lymphocytes as well as those of monocytes were significantly increased in the patients' group. The percentage of T3+ lymphocytes was found decreased in SCD. However, a rise in the number of T11+ and T4+ lymphocytes as well as in the helper/suppressor cell ratio was observed in the patients as compared to controls.