SUSCEPTIBILIDAD ANTIMICROBIANA DE AISLAMIENTOS DE Salmonella entérica PROVENIENTES DE PISOS, EQUIPOS, UTENSILIOS Y PRODUCTO TERMINADO EN PLANTAS DE BENEFICIO PORCINO EN COLOMBIA / ANTIMICROBIAL SUSCEPTIBILITY OF Salmonella enterica STRAINS ISOLATED FROM FLOORS, EQUIPMENT, MACHINERY, AND FINISHED PRODUCT IN PORCINE SLAUGHTERHOUSES IN COLOMBIA

La diseminación de Salmonella spp. resistente a antimicrobianos en las cadenas productivas de alimentos de origen animal es una preocupación de salud pública de carácter mundial. Este estudio describe los patrones de resistencia antimicrobiana de 283 aislamientos de Salmonella enterica procedentes de plantas de beneficio porcino en Colombia. Se evaluó la susceptibilidad antimicrobiana frente a diez antimicrobianos mediante el método de difusión en disco: amoxacilina-ácido clavulánico (30 ug), ampicilina (10 ug), ceftiofur (30 ug), ciprofloxacina (5 ug), cloranfenicol (30 ug), florfenicol (30 ug), gentamicina (10 ug), sulfadiazina/trimetroprim (25 ug), tetraciclina (30 ug) y tilmicosina (15 ug). Los resultados evidenciaron la presencia de 279 aislamientos multirresistentes de Salmonella enterica de origen porcino provenientes del ambiente y del producto terminado en las plantas de beneficio evaluadas (46,64% n: 132). Se detectaron 52 patrones de multiresistencia: el más común fue ceftiofur-tetraciclina-tilmicosina en el 9,89% (n: 28) de los aislamientos. Con referencia a estos antimicrobianos, 96,82% (n: 274) de los aislamientos fueron resistentes a tetraciclina, 73,14% (n: 207) a tilmicosina y 28,27% (n: 80) a ceftiofur. De especial interés fue la alta proporción de aislamientos resistentes a ceftiofur, debido a una posible resistencia cruzada con ceftriaxona. Los resultados obtenidos demuestran la necesidad de promover el diseño e implementación de un Programa oficial Integrado de Vigilancia de la Resistencia Antimicrobiana, además de sistemas de monitoreo voluntario en cada eslabón de la cadena productiva porcina, para contribuir a la prevención y control de la transmisión de microorganismos resistentes de origen alimentario en el marco del sistema de gestión de inocuidad alimentaria en Colombia.

The development and spread of antimicrobial multidrug resistance_of Salmonella spp. from food chain is a public health concern global. This study aimed to describe the antimicrobial resistance patterns of 283 isolates of Salmonella enterica from pork slaughterhouse in Colombia. Antimicrobial susceptibility on ten antimicrobials was evaluated: amoxicillin - clavulanic acid (30 ug), ampicillin (10 ug), ceftiofur (30 ug), ciprofloxacin (5 ug), chloramphenicol (30 ug), florfenicol (30 ug), gentamicin (10 ug), sulfadiazine/trimethoprim (25 ug), tetracycline (30 ug) and tilmicosin (15 ug) using the disc diffusion method. The results showed the high presence of isolates multidrug resistant of Salmonella enterica widespread on environmental of slaughterhouse (46.64% n: 132). 52 multidrug resistance patterns were detected. The most common was ceftiofur - tetracycline - tilmicosin in 9.89% (n = 28) of isolates. These same three antimicrobials were less effective with 96.82 % (n = 274) resistant-isolates against tetracycline, 73.14 % (n = 207) against tilmicosin and 28.27 % (n = 80) against ceftiofur. Of particular concern was the high rate of resistance to ceftiofur due to its cross-resistance to ceftriaxone. The results demonstrate the need to promote and strengthen an official Integrated Program for Antimicrobial Resistance Surveillance and volunteer monitoring systems in each link of the porcine production chain, to contribute to the prevention and control of food-borne infections in the context of safety management system in Colombia.

Naturally occurring heavy radioactive elements in the geothermal microcosm of the Los Azufres (Mexico) volcanic complex.

The Los Azufres geothermal complex of central Mexico is characterized by fumaroles and boiling hot-springs. The fumaroles form habitats for extremophilic mosses and ferns. Physico-chemical measurements of two relatively pristine fumarolic microcosms point to their resemblance with the paleo-environment of earth during the Ordovician and Devonian periods. These geothermal habitats were analysed for the distribution of elemental mass fractions in the rhizospheric soil (RS), the native volcanic substrate (VS) and the sediments (S), using the new high-sensitivity technique of polarized x-ray energy dispersive fluorescence spectrometry (PEDXRF) as well as instrumental neutron activation analysis (INAA) for selected elements. This work presents the results for the naturally occurring heavy radioactive elements (NOHRE) Bi, Th and U but principally the latter two. For the RS, the density was found to be the least and the total organic matter content the most. Bi was found to be negligibly present in all substrate types. The average Th and U mass fractions in the RS were higher than in the VS and about equal to their average mass fractions in the S. The VS mass fraction of Th was higher, and of U lower, than the mass fractions in the earth's crust. In fact for the fumaroles of one site, the average RS mass fractions of these elements were higher than the averaged values for S (without considering the statistical dispersion). The immobilization of the NOHRE in the RS is brought about by the bio-geochemical processes specific to these extremophiles. Its effectiveness is such that despite the small masses of these plants, it compares with, or may sometimes exceed, the immobilization of the NOHRE in the S by the abiotic and aggressive chemical action of the hot-springs. These results indicate that the fumarolic plants are able to transform the volcanic substrate to soil and to affect the NOHRE mass fractions even though these elements are not plant nutrients. Mirrored back to the paleo times when such plant types were ubiquitous, it would mean that the first plants contributed significantly to pedogenesis and the biogeochemical recycling of even the heaviest and radioactive elements. Such plants may potentially be useful for the phytostabilisation of soil moderately contaminated by the NOHRE. Furthermore where applicable, geochronology may require taking into account the influence of the early plants on the NOHRE distributions.

Standards for mesiodistal and buccolingual crown size and height of primary molars in a sample of Spanish children.

AIM: The aim of this study was to obtain mesiodistal, buccolingual and height sizes of dental crowns of first and second primary molars in a sample of Spanish children given, not only their anthropological and forensic significance, but also their clinical interest for the future analysis of restorative and orthodontic treatments. MATERIALS AND METHODS: Measurements of mesiodistal, buccolingual size and height of the crowns of primary molars were studied. A transversally descriptive design was carried out and the interrelationship between these three dimensions was established. A sample of 703 first and second primary molars was selected from healthy Spanish boys and girls from 4 to 9 years old. Molars presenting anomalies of the crowns, caries or restorations were excluded. Measurements were made on dental plaster models, using a vernier caliper. Descriptive statistics and Pearson correlation coefficient was obtained and Wilcoxon's non- parametric test was applied for comparison of the mean, analysis of sexual dimorphism and comparison of antimeric teeth. RESULTS: Average sizes of each group of molars were obtained. Sexual dimorphism was studied utilizing the Wilcoxon test. A variability of relationship between the measurements was found in each molar studied. Primary second molars had less variability than first molars in the three measurements obtained. The measurement with the least variability was height, followed by mesiodistal size. CONCLUSIONS: Measurements of primary molars showed that average sizes of boys' molars were significantly larger than those of girls. Relationship between the three measurements studied was variable but second molars showed less variability than first molars. The relationship between height and width was found significant in most of the molars. i.

Local heterogeneity in the pressure denaturation of the coiled-coil tropomyosin because of subdomain folding units.

Coiled-coil domains mediate the oligomerization of many proteins. The assembly of long coiled coils, such as tropomyosin, presupposes the existence of intermediates. These intermediates are not well-known for tropomyosin. Hydrostatic pressure affects the equilibrium between denatured and native forms in the direction of the form that occupies a smaller volume. The hydrophobic core is the region more sensitive to pressure, which leads in most cases to the population of intermediates. Here, we used N-(1-pyrenyl)iodoacetamide covalently bound to cysteine residues of tropomyosin (PIATm) and high hydrostatic pressure to assess the chain interaction and the inherent instability of the coiled-coil molecule. The native and denatured states of tropomyosin were determined from the pyrene excimer fluorescence. The combination of low temperature and high pressure permitted the attainment of the full denaturation of tropomyosin without the separation of the subunits. High-temperature denaturation of Tm leads to a great exchange between labeled and unlabeled Tm subunits, indicating subunit dissociation linked to unfolding. In contrast, under high pressure, unlabeled and labeled tropomyosin molecules do not exchange, demonstrating that the denatured species are dimeric. The decrease of the concentration dependence of PIATm corroborates the idea that pressure produces subdomain denaturation and that the polypeptide chains do not separate. Substantial unfolding of tropomyosin was also verified by measurements of tyrosine fluorescence and bis-ANS binding. Our results indicate the presence of independent folding subdomains with different susceptibilities to pressure along the length of the coiled-coil structure of tropomyosin.

Fine-needle aspiration diagnosis of Kaposi's sarcoma in a developing country.

Fine-needle aspiration (FNA) cytology was performed on 15 patients with peripheral lymphadenopathy and/or skin lesions referred to the Department of Pathology of the Hospital Central of Maputo, Maputo, Mozambique. Epitrochlear lymph nodes were the most frequently aspirated site. All aspirates allowed diagnoses of Kaposi's sarcoma (KS). Smears contained loosely cohesive clusters of bland spindle cells, with a radial arrangement and nuclear crush artifacts. These diagnostic clues have not been described in other spindle-cell intranodal lesions that should be considered in differential diagnoses. Taking into consideration the high prevalence of AIDS and limited resources for diagnosis in Africa, FNA cytology appears to be a useful method for the diagnosis of KS in developing countries, reducing the necessity for surgical lymph node excision.

Developing expressed sequence tags (ESTs) from polymorphic transcript-derived fragments (TDFs) in cassava (Manihot esculenta Crantz).

We applied the cDNA-AFLP (amplified fragment length polymorphism) technique to mRNA from the parents of a cassava (Manihot esculenta) genetic mapping population, and obtained more than 500 transcript-derived fragments (TDFs) that were unique in either parent. A subset of 50 TDFs were cloned and sequenced. Sequence alignment of the expressed sequence tags (ESTs) revealed mostly genes of unknown function. Six of the TDFs were mapped on to the cassava genetic map. We also demonstrated by genetic mapping of the TDFs, as RFLP (restriction fragment length polymorphism) markers, that TDFs are more polymorphic than random cDNAs. Generation of ESTs as differentially expressed sequences, in time or between different varieties, is proposed as a way of developing ESTs around specific traits for the candidate locus approach to mapping complex traits.

[Use of the ankle/arm index obtained by echo-Doppler as a diagnostic method in peripheral arteriopathies in primary care]. / Uso del índice tobillo/brazo (t/b) obtenido por eco-Doppler como método diagnóstico en arteriopatías periféricas en atención primaria.

OBJECTIVE: To describe the use of the ankle/arm index obtained by echo-doppler as a method of assessing patients with a clinical picture suggesting peripheral arteriopathy. SETTING: Sama de Langreo Health Centre (Asturias). PATIENTS: 83 patients (166 cases) between 23 and 90, who attended for treatment and had a possible diagnosis of peripheral arteriopathy. MEASUREMENTS AND MAIN RESULTS: The existence of pedal and posterior tibial pulses was explored by echo-doppler; then the arm/ankle index was calculated. Data on age, sex and concomitant pathologies were collected. The pedal pulse was negative in 11.4%, the posterior tibial in 9.2%. The arm/ankle index was significantly lower in males (0.86) than in women (1.07) (Student's t test 5.11, p < 0.0001). It was lower in diabetics (0.896) than in non-diabetics (0.95), but this was not significant (Student's t 0.99, p < 0.323). CONCLUSIONS: Echo-doppler measurement of the ankle-arm index is confirmed as a valid instrument to assist diagnosis and assessment of the severity of ischaemia in Primary Care patients whose clinical picture suggests peripheral arteriopathy.

Mimicry of the calcium-induced conformational state of troponin C by low temperature under pressure.

Calcium binding to the N-domain of troponin C initiates a series of conformational changes that lead to muscle contraction. Calcium binding provides the free energy for a hydrophobic region in the core of N-domain to assume a more open configuration. Fluorescence measurements on a tryptophan mutant (F29W) show that a similar conformational change occurs in the absence of Ca2+ when the temperature is lowered under pressure. The conformation induced by subzero temperatures binds the hydrophobic probe bis-aminonaphthalene sulfonate, and the tryptophan has the same fluorescence lifetime (7 ns) as in the Ca2+-bound form. The decrease in volume (delta V = -25.4 ml/mol) corresponds to an increase in surface area. Thermodynamic measurements suggest an enthalpy-driven conformational change that leads to an intermediate with an exposed N-domain core and a high affinity for Ca2+.

[Attitude to incurable disease]. / Actitud ante una enfermedad incurable.

OBJECTIVE: To find the opinions and attitudes of our patients regarding questions of incurable disease and death. DESIGN: A crossover, descriptive study. SETTING: 2 medical clinics and 2 nursing stations at 2 health centres. PATIENTS: 720 patients between 14 and 90 seeking health-care. Sampling of their appropriateness was performed, with systematic daily questionnaires. Known carriers of cancer or AIDS were excluded, as were those with understanding, communication or hearing problems. MEASUREMENTS AND RESULTS: A survey was carried out after a pilot period, using a specially composed questionnaire with seven closed questions. The study period was three months. 60.8% of those questioned would be willing to tell a close family member if the latter had an incurable illness; 60.9% would allow a doctor to do so. 69% would want to be told the truth if they suffered an incurable illness, with 57.3% opting for a doctor as spokesperson. 58.6% would prefer to die at home and 31.3% in hospital. Preference for hospital was unconnected to age or fear of pain. 44% pointed to pain as their greatest fear in an incurable illness, followed by 25.7% whose greatest fear was disability. CONCLUSIONS: On the whole, our patients seemed favorable to telling the truth about a hypothetical incurable illness, whether their own or a family member's. The majority would prefer to die at home and mainly fear pain.

Reassembly of a large multisubunit protein promoted by nonprotein factors. Effects of calcium and glycerol on the association of extracellular hemoglobin.

The effects of cations and glycerol on the dissociation induced by pressure and on the reassembly of Glossoscolex paulistus hemoglobin were examined by light scattering, gel filtration, and electron microscopy. Calcium stabilized the quaternary structure of the hemoglobin against pressure dissociation. In the presence of 50 mM Ca2+, the half-dissociation pressure (p 1/2) increased by 400 bar, which corresponds to an average stabilization of -0.62 kcal/mol of dissociating subunit. Calcium also promoted a large increase in the yield of recovery of fully assembled hemoglobin at the expense of the partially dissociated (one-twelfth subunit) and fully dissociated forms. Glycerol protected the hemoglobin from pressure dissociation, increasing the half-dissociation pressure (p 1/2) and promoted an increase in the yield of recovery of fully assembled hemoglobin by about 40%. Addition of calcium after return to atmospheric pressure increased recovery of the fully associated form only in a long time scale (many days). The existence of time-dependent changes in the conformation of the dissociated subunits is suggested to explain the partial association to one-twelfth subaggregates (drifted forms) that lack the ability to reassemble to native hemoglobin. The promotion of reassembly by nonprotein factors (calcium and glycerol) is suggested to occur by preventing the formation of wrong intermediate forms (drifted one-twelfth subunits).

Extraosseous sarcoma. A case report.

Extraskeletal osteosarcoma is very rare and is difficult to diagnose histologically. We report a case of a 63 year old women who had such a tumour in her thigh.

Frequency of five genetic polymorphisms in two populations of Colombia

As prevalências dos alelos dos sistemas da glicose-6-fosfato desidrogenase (G6PD), hemoglobina (Hb), ABO, Rh e haptoglobina (Hb) foram investigadas em duas populaçöes colombianas miscigenadas de origem predominantemente indígena (da tribo Noanama) e africana. Entre os negróides os marcadores para G6PD, Rh e Hp mostraram as freqüências esperadas, mas os valores relativamente altos encontrados para Hb*C (0,057) e ABO*O (0,853), assim como o baixo para ABO*B (0,046), devem ser enfatizados. Os resultados relativos à hemoglobina podem ser explicados por imigraçäo de pessoas de áreas com altas prevalências de Hb*C na Africa, ou sobrevivência diferencial de portadores deste gene na Colombia; enquanto os achados no ABO podem refletir mistura com Ameríndios. A presença de um indivíduo deficiente para G6PD, assim como a ocorrência de Hb*C (0,106), ABO*A (0,260) e ABO*B (0,027) entre aqueles classificados como Ameríndios sugere nível alto de mistura, mas a ausência de Rh (-) entre eles está de acordo com o esperado. O número de tipagens para haptoglobina realizadas neste grupo foi baixo; a freqüência observada de Hp*1 (0,700) é similar à encontrada em índios sul-americanos em geral, mas difere da prevalência observada em um estudo prévio de índios Noanama

Preliminary pharmacobiological study of new steroidal sapogenins.

The chemotherapeutic study of a limited series of steroidal sapogenins from several endemic species of the flora of the Canary Islands is presented here. On the whole, they possess a very weak antibacterial activity, a slight antifungal effect and one of them, vespertilin, displays interesting cytostatic activity (ID50 = 5 micrograms/ml). A pharmacodynamic screening carried out on this product mainly revealed very slight toxicity, antihistaminic activity and a light tranquilizing effect. The data obtained justify further research.