Comparison of sediment bioavailable methods to assess the potential risk of metal(loid)s for river ecosystems.

A heavily impacted river basin (Caudal River, NW Spain) by Hg and Cu mining activities, abandoned decades ago, was used to evaluate the environmental quality of their river sediments. The obtained results compared with reference values established by the US EPA and the Canadian Council of Ministers of the Environment for river sediments, have shown that the main elements of environmental concern are arsenic (As), mercury (Hg) and, to a lesser extent, copper (Cu), which reach concentrations up to 1080, 80 and 54 mg kg-1, respectively. To understand the role that river sediments play in terms of risk to ecosystem health, a comparison has been made between the total content of metal(oid)s in the sediments and the bioavailable contents of the same elements in pore water, passive DGT (Diffusive Gradients in Thin films) samplers and the sediment extractant using acetic acid. A good correlation between the As and Cu contents in the DGTs and the pore water was found, resulting in a transfer from the pore water to the DGT of at least 47 % of the Cu and more than 75 % of the As when the concentrations were low, with a deployment time of 4 days. When As and Cu concentrations were higher, their transfer was not so high (above 23.6 % for As and 19.3 % for Cu). The transfer of Hg from the pore water to the DGT was practically nil and does not seem to depend on the content of this metal. The fraction extracted with acetic acid, conventionally accepted as bioavailable, was clearly lower than that captured by DGTs for As and Cu (≤5 % and ≤8.5 % of the total amount, respectively), while it was similar for Hg (0.2 %).

How does an Al-hyperaccumulator plant respond to a natural field gradient of soil phytoavailable Al?

The physiological ability of plants to cope with Al-toxicity has attracted considerable attention. In this study we used an endemic Al-hyperaccumulator plant, Plantago almogravensis, which is the only known representative of the Plantaginaceae with this trait growing under a field gradient of Al, to understand the root and shoot patterns of Al accumulation and tolerance in its natural environment. We analysed phytoavailable elements in the soil and their accumulation in the plant. For the first time under field conditions, the accumulation pattern of an Al-hyperaccumulator showed a saturation curve with a maximum accumulation capacity being reached (ca. 3.0 mg g(-1)). The Al toxicity was not associated with the expected reduction in the Ca and Mg uptake by the plant. Iron was accumulated in a more linear pattern. The magnitude and the proportion of the elements found in the apoplastic fraction of the root, compared to the soil and plant internal fractions, suggested that the control of uptake occurs at the rhizospheric level. Unlike the majority of the Al-hyperaccumulator plants that are found in tropical humid areas, this plant is described from a sub-arid Mediterranean climate, subject to drought conditions which give it a unique status that deserves to be studied further.

Marcadores de alergia alimentaria en enfermedad péptica / Food allergy markers in peptic disease

Background: The double-blind food challenge is the gold standard for diagnosis of food allergy, even though it is difficult to standardize and execute. An increase in allergy prevalence worldwide accentuates the importance of evaluating food allergy markers, in order to help the diagnosis. Objective: Elaboration of an operational definition for food hypersensitivity (FH) and evaluate the role of allergy markers, endoscopic and histological findings, gastric mucosa cytokines and personal/family history of allergy in children. Method: Enrollment of children with suspected peptic disease referred for endoscopy. We obtained antral biopsies for histological evaluation (eosinophil and mast cell count) and measurement of mucosal cytokines through an ELISA test. Patients were evaluated with Prick test, total serum IgE and clinical questionnaires for allergies. They were divided into two groups; children with and without food hypersensitivity. Results: 97 children were enrolled (mean: 11.7 +/- 3, range 3-18). 4 percent of children had FH. The endoscopic findings did not correlate with the presence of FH. 74.1 percent of patients without FH had eosinophils in the gastric mucosa compared to groups with FH which had 100 percent) (p < 0.05). Only IL-2 among the evaluated cytokines was found in a greater concentration in patients without FH. 33 percent> of patients considered themselves having history of personal allergies versus 11.8 percent of people without FH (p < 0.05). Conclusions: 12,4 percent of children with digestive symptoms referred to endoscopy have FH. There are no clinical, endoscopic or histological differences between patients with or without FH.

Introducción: El diagnóstico de alergia a alimentos se fundamenta en la prueba de provocación oral doble ciego, de difícil estandarización y ejecución. El aumento de la prevalencia de alergia hace necesario la evaluación de marcadores de alergia a alimentos para facilitar el diagnóstico. Objetivo: Evaluar en niños, a partir de una definición operacional de hipersensibilidad a alimentos (HA), el rol de algunos marcadores de hipersensibilidad, hallazgos endoscópicos e histológicos, citoquinas de mucosa gástrica, y antecedentes personales y familiares de alergia. Métodos: Se enrolaron niños referidos a endoscopia por sospecha de enfermedad péptica. Se obtuvieron biopsias antrales para evaluación histológica (incluyendo eosinófilos y mastocitos) y citoquinas mediante ELISA. Se les realizó test cutáneo (TC), IgE total sérica y cuestionarios clínicos de alergia. Se dividió en 2 grupos, niños con y sin HA según criterio establecido. Resultados: Se reclutaron 97 niños (promedio: 11,7 +/- 3 años, rango 3 a 18). Un 12,4 por ciento de los niños presentó HA. Los hallazgos endoscópicos no se relacionaron con la presencia de HA. Un 74,1 por ciento de los pacientes sin HA presentó eosinófilos en la mucosa gástrica comparado con un 100 por ciento en el grupo con HA (p < 0,05). Sólo IL-2 se encontró en mayor concentración en pacientes sin HA. Un 33,3 por ciento de la población con HA consideró tener antecedentes personales de AA versus un 11,8 por ciento de los sin HA (p < 0,05). Conclusiones: La HA en niños referidos a endoscopia por síntomas digestivos está presente en un 12,4 por ciento, sin elementos clínicos, endoscópicos o histológicos que los diferencien de niños sin HA.

El melanoma subungueal: un retodiagnóstico / Subungueal melanoma: a challenge for the diagnosis

El melanoma subungueal sufre con frecuencia un importante retraso en el diagnóstico.Presentamos el caso de una paciente con cambios ungueales distróficos que fueron diagnosticados en nuestro Servicio como onicomicosis, debido a laclínica y al cultivo de hongos positivo, pero que, al realizar una biopsia, dada la mala respuesta al tratamiento antifúngico, mostró una histología demelanoma lentiginoso acral con avanzada invasión local.En el siguiente artículo se revisan las principales características clínicas que pueden orientarnos hacia el diagnóstico precoz del melanoma subungueal,así como la utilidad de la dermatoscopia en el diagnóstico de esta neoplasia; siempre teniendo en cuenta que el diagnóstico definitivo se establece pormedio de la biopsia (AU)

Diagnosis of subungual melanoma is usually difficult and often is a delayed diagnosis. A patient with nail dystrophy that was diagnosed as a onychomicosisby means of mycological culture is reported. The patient don´t responded to the treatment during three weeks, so, we made a biopsy that showedthe diagnosis of acral lentiginous melanoma.In this article, we review the world literature on subungual melanoma and arranged the available information in a system for the clinical detection ofsubungual melanoma. We believe that dermoscopic examination of the nail plate in cases of melanonychia provides useful information that couldhelp to decide if a nail apparatus biopsy should be performed; however, the absolute diagnosis of subungual melanoma is made by means of a biopsy (AU)

Instilación intratraqueal de elastasa en la rata: cambios electroforéticos de la alfa1-AT-antitripsina en el lavado broncoalveolar / Intratracheal instillation of elastase in the rat: electrophoretical changes of alphal-antitrypsin in bronchoalveolar lavage fluid

Introduction: Endogenous alphal-antitrypsin alpha is the main inhibitor of the intratracheally instilled elastase in experimental animals. Objective: To evaluate by electrophoresis and immunodetection using western blot analysis, the different forms of alpha1-AT in bronchoalveolar lavage fluid (BALF) of Sprague Dawley rats after intratracheal instillation of elastase, with the hypothesis that the previously observed increment in antielastase activity is due to high levels of active alpha1-AT. Results: In the first hours after elastase instillation the concentration of alpha1-AT increases more than seven times due to an increase in alveolar-capillary permeability. Alpha 1-AT in BAIF is found as the native protein (~ 52 kDa), as complexes of different molecular sizes (> 75 kDa and > 100 kDa) and as a proteolytic product (< 40 kDa). Conclusion: In spite of a high proportion of alpha1-AT in the inactive form as part of different complexes, the increase in alveolar-capillary permeability after elastase treatment contributes to maintain high levels of active alpha. These results could be of importance in other inflammatory lung processes.

Introducción: la antiproteasa alfa 1-antitripsina alfa constituye el principal inhibidor endógeno de la elastasa instilada por vía intratraqueal en modelos experimentales. Objetivo: Evaluar mediante electroforesis e inmunodetección por western blot, las distintas formas en que se encuentra la alfa1-AT en el lavado broncoalveolar (IBA) de ratas Sprague Dawley después de la instilación de elastasa, con la hipótesis de que el aumento en la actividad antielastasa previamente encontrada se acompaña de niveles altos de alfa1-AT activa. Resultados: En las primeras horas post-elastasa la concentración de alfa1-AT en el IBA aumenta más de 7 veces, debido al aumento de la permeabilidad alvéolo-capilar, encontrándose tanto como proteína nativa (~ 52 kDa), como parte de complejos de mayor tamaño (> 75 kDa y > 100 kDa) y como producto de proteólisis (< 40 kDa). Conclusión: A pesar de existir una alta proporción de alfa1-AT inactiva formando complejos, el aumento de la permeabilidad alvéolo-capilar contribuye a mantener niveles altos de alfa1-AT activa. Estos resultados podrían ser extrapolables a distintos procesos inflamatorios pulmonares.

[Diagnosis of Helicobacter pylori infection in children based on stool antigen test]. / Diagnóstico de la infección poe Helicobacter pylori en niños mediante la detección de antígenos en deposiciones.

BACKGROUND: During infancy, preventive, diagnostic and therapeutic efforts for Helicobacter pylori infection should be made. AIM: To evaluate non-invasive diagnostic methods such as stool antigen test (HpSA) and serum anti-H pylori antibody detection (IgG e IgA), compared to endoscopy-based invasive methods (histology and urease test) for the diagnosis of Helicobacter pylori infection. PATIENTS AND METHODS: Thirty nine children (aged 3 to 14 years, 20 males) referred for upper gastrointestinal endoscopy, were studied. The gold standard to diagnose Helicobacter pylori infection was defined as a positive invasive diagnostic test (histology and/or urease test). Sensitivity (S), specificity (E) and positive (PPV) and negative (NPV) predictive values were obtained for HpSA and serum antibodies. RESULTS: Ten children (26%) were infected with H pylori. S, E, PPV and NPV for HpSA were 90, 100, 100 and 97%, respectively. The figures for serum IgG were 81, 97, 89 and 93%, respectively and for IgA, 90, 76, 36 and 96%, respectively. CONCLUSIONS: HpSA was sensitive and specific as a clinical and epidemiological tool to evaluate H pylori infection in children. Serology was not as accurate, but IgG had a better performance than IgA.

Diagnóstico de la infección poe Helicobacter pylori en niños mediante la detección de antígenos en deposiciones / Diagnosis of Helicobacter pylori infection in children based on stool antigen test

Background: During infancy, preventive, diagnostic and therapeutic efforts for Helicobacter pylori infection should be made. Aim: To evaluate non-invasive diagnostic methods such as stool antigen test (HpSA) and serum anti-H pylori antibody detection (IgG e IgA), compared to endoscopy-based invasive methods (histology and urease test) for the diagnosis of Helicobacter pylori infection. Patients and Methods: Thirty nine children (aged 3 to 14 years, 20 males) referred for upper gastrointestinal endoscopy, were studied. The gold standard to diagnose Helicobacter pylori infection was defined as a positive invasive diagnostic test (histology and/or urease test). Sensitivity (S), specificity (E) and positive (PPV) and negative (NPV) predictive values were obtained for HpSA and serum antibodies. Results: Ten children (26 percent) were infected with H pylori. S, E, PPV and NPV for HpSA were 90, 100, 100 and 97 percent, respectively. The figures for serum IgG were 81, 97, 89 and 93 percent, respectively and for IgA, 90, 76, 36 and 96 percent, respectively. Conclusions: HpSA was sensitive and specific as a clinical and epidemiological tool to evaluate H pylori infection in children. Serology was not as accurate, but IgG had a better performance than IgA.

Vacunas en desarrollo: Helicobacter pylori / Vaccines under development: Helicobacter pylori

La infección con Helicobacter pylori es la causa de patologías gastrointestinales como úlcera péptica y cáncer gástrico. Una vacuna contra H. pylori es relevante debido a la alta prevalencia de la infección y a la morbi-mortalidad asociada a ésta en nuestro país. El uso masivo de terapias antimicrobianas actuales no es una estrategia factible, especialmente en países en desarrollo, en parte debido al alto costo, los múltiples efectos adversos, el riesgo de reinfección y la emergencia de resistencia a los antimicrobianos. Numerosos modelos animales han sido utilizados durante años para determinar el curso de la infección por H. pylori y explorar la factibilidad de una vacuna, ya sea para erradicar o prevenir la infección. Dichos modelos, con la posible excepción de los monos, no son suficientes para responder preguntas fundamentales debido a resultados contradictorios. Un modelo humano de infección por H. pylori debe ser desarrollado con el principal propósito de seleccionar vacunas óptimas. El objetivo final es el desarrollo de estudios de campos de vacunas candidatas, pero el estado actual del conocimiento no proporciona una metódica adecuada para seleccionar tales vacunas candidatas promisorias. Dichos estudios pueden ser diseñados para proporcionar información relevante sobre la inmunidad y patogénesis de la infección por H. pylori.

[Vaccines under development: Helicobacter pylori]. / Vacunas en desarrollo: Helicobacter pylori.

Helicobacter pylori causes gastrointestinal disease including peptic ulcer and gastric cancer. An H. pylori vaccine is relevant because of the high prevalence of the infection and its associated complications. Extensive use of traditional antimicrobial therapies to eradicate H. pylori is not feasible, specially in developing countries, in part because of their high cost, associated adverse effects, the risk of reinfection, and the emergence of antimicrobial drug resistance. Numerous animal studies have been performed to determine infection outcomes and to explore the feasibility of a vaccine eradication or prevention of infection. These animal models with the possible exception of monkeys, have not been sufficient to address fundamental issues due to controversial results. A human model of H. pylori infection needs to be developed aimed to select an optimum vaccine candidate. The ultimate scientific goal will be to develop field studies using advanced vaccine candidates, but the current state of knowledge does is insufficient and has provided such candidates. These studies need to be designed in order to provide relevant information on immunity and pathogenesis associated to H. pylori.

Utilidad del diagnóstico serológico de la infección por Helicobacter pylori en niños / Serological diagnosis of Helicobacter pylori infection in children

Helicobacter pylori (H. pylori) afecta al 50 por ciento de la población mundial. La infección se adquiere en la infancia; siendo justamente el grupo pediátrico en el cual impera la necesidad de validar métodos diagnósticos no invasivos que permitan diagnosticar la infección. El objetivo de este trabajo fue revisar la literatura sobre el diagnóstico serológico de la infección por H. pylori, con especial énfasis en población pediátrica. La mayor utilidad de la serología ha sido en estudios epidemiológicos, al permitir conocer la prevalencia de la infección. En pacientes adultos esta técnica presenta valores de sensibilidad y especificidad superiores al 90 por ciento y es comparable a métodos diagnósticos invasivos; la situación cambia en población pediátrica, sobre todo en el grupo de niños pequeños donde la serología pierde mucho de su sensibilidad y especificidad, lo cual restringe el uso de la serología para propósitos clínicos en población infantil.

IgG antibodies to enterobacteria 60 kDa heat shock proteins in the sera of HLA-B27 positive ankylosing spondylitis patients.

OBJECTIVE: To study the association of HLA-B27 and the IgG response to the 60 kDa HSPs of Klebsiella pneumoniae, Yersinia enterocolitica, Shigella flexneri, Escherichia coli and Salmonella typhi. METHODS: IgG against the 60 kDa HSPs of enterobacteria was determined by ELISA in the sera from 49 HLA-B27+ ankylosing spondylitis (AS) patients; 41 HLA-B27+ healthy relatives of AS patients and 101 HLA-B27-unrelated healthy individuals. RESULTS: HLA-B27+ patients and healthy individuals, showed significantly higher IgG antibody levels to the Klebsiella, Yersinia and Salmonella HSPs than HLA-B27- healthy controls. B27+ patients had a significantly higher response to E. coli HSP than the two other groups. IgG response anti-Shigella HSP was similar in the three groups. CONCLUSIONS: There is a relationship between HLA-B27 and the response to HSPs 60 from Klebsiella, Yersinia, Escherichia and Salmonella, that may be important in the initiation of AS.

Molecular aspects of mammalian fertilization.

Mammalian fertilization is a highly regulated process, much of which are not clearly understood. Here we present some information in order to elaborate a working hypothesis for this process, beginning with the sperm modifications in the epidydimis up to sperm and egg plasmalemma interaction and fusion. We also discuss the still poorly understood capacitation process, the phenomenon of sperm chemo-attraction that brings the capacitated sperm to interact with the oocyte vestments and certain aspects of the acrosome reaction.

Pig sperm membrane integrity evaluated by lectin labeling.

Sperm integrity is one of the most carefully examined characteristics for artificial insemination in humans and mammals. Techniques have been developed to assess the sperm plasma membrane integrity. Some of them need a well-trained evaluation for correctness, as is the case of the triple stain technique; others are time-consuming and need special equipment, varying from specially adapted microscopes to computer-based analyzers. The authors report the use of fluorescein-labeled peanut agglutinin plus a fluorescein extender that permits an easy evaluation for pig spermatozoa membrane integrity. Sperm integrity in pigs was evaluated before and after zona pellucida-induced acrosome reaction in capacitated sperm. The sperm acrosome reaction was affected when the zona pellucida was reduced.

Sperm-attracting activity in follicular fluid associated to an 8.6-kDa protein.

Follicular fluid is made of both follicular cell-secreted molecules as well as blood infiltration into the follicle. Sperm-attracting activity has been associated to column-filtered proteins as well as to progesterone. Here we report the initial characterization of a protein with this activity. Follicular fluid was collected from preovulatory follicles in freshly obtained ovaries from a local slaughterhouse. Fluid was cleared from cells and fractionated by size exclusion chromatography and polyacrylamide gel electrophoresis. For gamete interaction, sperm were allowed to swim in an agarose-covered slide designed to separate two wells by a rod in a fixed pattern. At each well, a semisolid agarose solution containing either the attractant with oocytes or control solution in one end, whereas capacitated boar sperm was at the opposite well. Sperm bound to oocytes were evaluated under phase contrast microscopy. Results show that fluid from preovulatory follicles have a sperm attracting activity and that this activity can be associated with an 8600 Dalton protein that at the N-terminal end exhibit close relation to Apoliprotein B2.

Sperm aggregation by water extracts from two Bursera species.

Some plants have more than the common utility value, as is the case of some members of the Bursera species such as the Mexican copal, a plant used for worship. Water extracts of several plants have vaginal contraceptive properties. The authors evaluated the sperm agglutinating activity of two Bursera species on human and boar sperm. Extracts from stems and leaves were obtained. Capacitated sperm samples were used in all cases. There were different agglutinating capacities, which were not observed in the vehicle-only samples. The most frequent sperm agglutination response was that involving the heads. Agglutinating activity was higher from stem- than leaf-derived extracts. The results indicate that proteins present in the extracts are responsible for the aggregation of sperm heads.

[Clinical features of dengue fever in children during the outbreak in Santiago de Cuba]. / Características clínicas de la fiebre de dengue en niños durante el brote epidémico en Santiago de Cuba.

A study of the dengue outbreak occurred from January to November 1997 in Santiago de Cuba municipality was performed to characterize the clinical picture of the patients. The sample was taken from those patients presenting with clinical and epidemiological elements and positive IgM determination serological test. Seventy-seven patients were confirmed as having dengue virus 2 infection whose clinical-humoral characteristic was dengue fever predominantly present in school boys. The clinical picture was given by fever headache, retrorbitary pain, osteomioarticular pain as the most common symptom and by exanthema as a prevailing sign. Most of bleedings occurred on the 2nd day and the most frequent hemorrhagic manifestation was positive tourniquet test.

[Hemorrhagic dengue in primary dengue]. / Dengue hemorrágico en dengue primario.

We described the clinical and humoral development of a 7-years old boy who had hemorrhagic dengue in the dengue epidemic taken place in Santiago de Cuba in 1997. During this stage, dengue was serologically confirmed in 77 patients under 15 years of age but only one case was considered to be hemorrhagic dengue in spite of the fact that the patient had no history of this disease and that the virus had not been circulating in the country for over 15 years. The boy was under shock on the fourth day of the process, with hemoconcentration, pleural and ascitic effusions, thrombocytopenia and later a nosocomial sepsis, but he completely recovered in a period of 20 days.

Sperm chromatin.

Available data on dry and hydrated nuclear volume of mammalian spermatozoa indicate that available volume is clearly insufficient to contain sperm chromatin packed in nucleosome-like structures. Therefore, sperm DNA-protein complexes must be packed differently than somatic DNA-protein complexes. Packing of DNA in fixed, dehydrated mammalian sperm approaches the physical limits of molecular compaction, making mammalian sperm chromatin the most condensed eukaryotic DNA known. The fundamental packaging unit of sperm chromatin is a toroid approximately 900-A outer diameter. 200-A thickness, and 150-A diameter hole. Each toroid contains 60 kilobases of DNA and is linked to other toroids by uncoiled DNA stretches. The factors that contribute to mammalian chromatin structuration are still under study. The role of protamines in sperm chromatin condensation and nuclear shaping has been overstressed to the exclusion of other possible factors. Chromatin organization in sperm nuclei is maintained during sperm condensation by tight interactions with the nuclear matrix at fixed sites, inducing the formation of individual toroid-shaped DNA loop stuctures. Observations that abnormal manchettes affect sperm head shape and chromatin organization inducing sterility speak about manchette importance during chromatin organization. The presence in sperm chromatin of regions packaged in specific ways with several types of protamines or even with histones, indicates that nuclear shaping and chromatin organization must be under DNA control. The structural properties that distinguish sperm DNA from somatic DNA may play the most important role in chromatin organization.

[Colonic involvement in ileal Crohn's disease]. / Etude de l'extension colique des maladies de Crohn iléales.

OBJECTIVES: To determine the risk and predictive factors for colonic extension in patients with ileal Crohn's disease. METHODS: One hundred and fifty patients with ileal Crohn's disease and no specific colonic lesions on initial colonoscopy were studied retrospectively (median follow-up: 51 months). RESULTS: Twelve patients (8%) developed colonic lesions. Ten-year cumulated risks (95% confidence interval) for colonic extension were 17.2% (range: 5.8-28.6) in the whole group, and 22.4% (range: 8.7-36.1) in the group of 86 patients with repeated colonoscopy. Young age at diagnosis was the only factor predicting colonic extension. Seven patients with colonic extension required immunosuppressive therapy but none underwent surgery. CONCLUSION: Ileal Crohn's disease has a low tendency for colonic extension. Colonic extension has no major prognostic implications.

Incidence of nonmelanoma skin cancer in New Hampshire and Vermont.

A survey of skin cancer occurrence between June 1979 and May 1980 among residents of New Hampshire and Vermont identified 277 cases of squamous cell carcinoma and 1761 cases of basal cell carcinoma. The age-adjusted incidence rates for squamous cell carcinoma (32 per 100,000 in men, 8 per 100,000 in women) and for basal cell carcinoma (159 per 100,000 in men, 87 per 100,000 in women) were similar to those reported in other populations in the northern United States. Skin cancer incidence was particularly high among men more than 70 years of age and a large proportion (greater than 30%) of patients 55 years or older had a history of at least one previous skin cancer.