[Communication with a culturally and linguistically diverse population from Primary Care]. / La comunicación con población cultural y lingüísticamente diversa desde la Atención Primaria.

The care of a culturally and linguistically diverse population is a challenge in primary health care due to language barriers and cultural differences. For this reason, good communication and cultural competence of health personnel is key within medical consultation. Thus, during consultations with this group of people, it is the doctor's duty to identify the patient's culture, their perception of the concept of health, in what way and to what extent they want to be informed, and the role they want to assign to the members of their family before the treatment process begins. For this reason, there are interventions that seek to optimize the care provided to these patients and mitigate the cultural barrier, including the use of multimodal digital tools, the use of translators or interpreters, and training of health personnel in communication and intercultural skills.

Resección por videotoracoscopía de nódulos pulmonares marcados con lipiodol: experiencia en dos centros universitarios / Videotoracoscopy resection of pulmonary nodules marked with lipiodol: experience in two university centers

INTRODUCCIÓN: Para facilitar la localización intraoperatoria de los nódulos pulmonares existe la alternativa de marcarlos previamente con lipiodol. OBJETIVO: Describir los resultados quirúrgicos de los pacientes sometidos a resección por videotoracoscopía de nódulos pulmonares marcados previamente con lipiodol. MATERIAL Y MÉTODOS: Estudio descriptivo. Se incluyeron los pacientes que fueron sometidos a resección por videotoracoscopía de nódulos pulmonares marcados con lipiodol, en Clínica Las Condes e Instituto Nacional del Tórax, entre junio de 2012 y junio de 2019. Se consideraron variables demográficas, radiológicas, quirúrgicas e histológicas. RESULTADOS: Se estudió un total de 93 pacientes. La edad promedio fue 63,5 (± 11,9) años. El tamaño promedio de los nódulos fue de 10,7 (± 5,8) mm. Se identificó y extrajo el 100% de los nódulos marcados. Los días de hospitalización promedio fueron 4,7 (± 6,9). Solo se registró un fallecimiento de causa no quirúrgica. CONCLUSIONES: La resección videotoracoscópica de nódulos pulmonares marcados previamente con lipiodol, es una técnica segura y eficaz.

BACKGROUND: To facilitate the intraoperative location of lung nodules there is the alternative of pre-marking them with lipiodol. OBJECTIVE: To describe the surgical results of patients undergoing videotoracoscopy resection of pulmonary nodules previously marked with lipiodol. MATERIAL AND METHODS: Descriptive study. Patients who underwent videotorcoscopy resection of pulmonary nodules marked with lipiodol were included at Clínica Las Condes and Instituto Nacional del Tórax between June 2012 and June 2019. Demographic, radiological, surgical and histological variables were considered. RESULTS: A total of 93 patients were studied. The average age was 63,5 (± 11.9) years. The average size of the nodules was 10.7 (± 5.8) mm. 100% of the marked nodules were identified and extracted. The average hospitalization days were 4.7 (± 6.9). Only one death of non-surgical cause was recorded. CONCLUSIONS: Videotoracoscopic resection of pulmonary nodules previously marked with lipiodol is a safe and effective technique.

Evaluation of Bone Mineral Density in Patients with Type 1 Gaucher Disease in Argentina.

The purpose of this study was to evaluate the frequency of osteoporosis (OP) in patients with Gaucher disease (GD) in Argentina. GD patients from 28 centers were consecutively included from April 2012 to 2014. Bone mineral density (BMD) was determined by dual X-ray absorptiometry in the lumbar spine and the femoral neck or the total proximal femur for patients ≥20 yr of age, and by whole-body scan in the lumbar spine in patients <20 yr of age. In children, mineral density was calculated using the chronological age and Z height. OP diagnosis was determined following adult and pediatric official position of the International Society for Clinical Densitometry. A total of 116 patients were included, of which 62 (53.5%) were women. The median age was 25.8 yr. All patients received enzyme replacement therapy, with a median time of 9.4 yr. Normal BMD was found in 89 patients (76.7%), whereas low bone mass (LBM) or osteopenia was found in 15 patients (13%) and OP in 12 patients (10.3%). The analysis of the pediatric population revealed that 4 patients (9.3%) had LBM and 3 (7%) had OP (Z-score ≤ -2 + fractures height-adjusted by Z), whereas in the adult population (n = 73), 11 patients (15%) had LBM or osteopenia and 9 (12.3%) had OP. Bone marrow infiltration and the presence of fractures were significantly correlated with the presence of OP (p = 0.04 and <0.001, respectively). This is the first study in Argentina and in the region describing the frequency of OP or LBM in GD patients treated with imiglucerase using the official position of the International Society for Clinical Densitometry.

Inhibition of enteropathogens adhesion to human enterocyte-like HT-29 cells by a dairy strain of Propionibacterium acidipropionici.

Adhesion to the host intestinal mucosa is considered relevant for orally delivered probiotics as it prolongs their persistence in the gut and their health promoting effects. Classical propionibacteria are microorganisms of interest due to their role as dairy starters as well as for their functions as probiotics. Propionibacterium acidipropionici Q4, is a dairy strain isolated from a Swiss-type cheese made in Argentina that displays probiotic potential. In the present work we assessed the ability of this strain to adhere to the human enterocyte-like HT-29 cell line and to counteract the adhesion of two common human enteropathogens, such as Escherichia coli C3 and Salmonella Enteritidis 90/390. The results were compared with those obtained with the well-known probiotic Lactobacillus rhamnosus GG. P. acidipropionici Q4 showed a high adhesion capacity, even higher than the reference strain L. rhamnosus GG (42.3±4.4% and 36.2±2.3%, respectively), whereas adhesion of enteropathogens was significantly lower (25.2±2.2% for E. coli and 21.0±3.4% for S. Enteritidis). Propionibacteria as well as lactobacilli were able to inhibit by exclusion and competition the adherence of E. coli C3 and S. Enteritidis 90/390 whereas only L. rhamnosus GG displaced S. Enteritidis from HT-29 intestinal cells. Inhibition of pathogens by propionibacteria was not exerted by antimicrobials or coaggregation but was mainly due to exclusion by cell surface components, such as proteins and carbohydrates. The relevance of cell surface proteins (CSP) for preventing pathogens infection was confirmed by their concentration dependent effect observed for both pathogens: 100 µg/ml of CSP inhibited E. coli attachment almost as untreated propionibacteria, whereas it partially inhibited the attachment of S. Enteritidis. Results suggest that P. acidipropionici Q4 could be considered for the development of propionibacteria containing functional foods helpful in counteracting enteropathogen infection.

Enhancing dendritic cell immunotherapy for melanoma using a simple mathematical model.

BACKGROUND: The immunotherapy using dendritic cells (DCs) against different varieties of cancer is an approach that has been previously explored which induces a specific immune response. This work presents a mathematical model of DCs immunotherapy for melanoma in mice based on work by Experimental Immunotherapy Laboratory of the Medicine Faculty in the Universidad Autonoma de Mexico (UNAM). METHOD: The model is a five delay differential equation (DDEs) which represents a simplified view of the immunotherapy mechanisms. The mathematical model takes into account the interactions between tumor cells, dendritic cells, naive cytotoxic T lymphocytes cells (inactivated cytotoxic cells), effector cells (cytotoxic T activated cytotoxic cells) and transforming growth factor ß cytokine (T G F-ß). The model is validated comparing the computer simulation results with biological trial results of the immunotherapy developed by the research group of UNAM. RESULTS: The results of the growth of tumor cells obtained by the control immunotherapy simulation show a similar amount of tumor cell population than the biological data of the control immunotherapy. Moreover, comparing the increase of tumor cells obtained from the immunotherapy simulation and the biological data of the immunotherapy applied by the UNAM researchers obtained errors of approximately 10 %. This allowed us to use the model as a framework to test hypothetical treatments. The numerical simulations suggest that by using more doses of DCs and changing the infusion time, the tumor growth decays compared with the current immunotherapy. In addition, a local sensitivity analysis is performed; the results show that the delay in time " τ", the maximal growth rate of tumor "r" and the maximal efficiency of tumor cytotoxic cells rate "aT" are the most sensitive model parameters. CONCLUSION: By using this mathematical model it is possible to simulate the growth of the tumor cells with or without immunotherapy using the infusion protocol of the UNAM researchers, to obtain a good approximation of the biological trials data. It is worth mentioning that by manipulating the different parameters of the model the effectiveness of the immunotherapy may increase. This last suggests that different protocols could be implemented by the Immunotherapy Laboratory of UNAM in order to improve their results.

CD11c decrease in mouse thymic dendritic cells after vanadium inhalation.

Vanadium (V) is a transition metal found in air adsorbed onto suspended particles. As a result, urban populations are often exposed to this element as a constituent of particulate matter (PM). One aspect of the myriad toxicities that might arise from these exposures is altered immune responses. Previous reports from the laboratory reported modifications in splenic architecture - with germinal center hyperplasia and a suppressed humoral immune response - in mice that had been exposed to vanadium agents via inhalation. This paper reports a decrease in the presence of the CD11c surface marker on mouse thymic dendritic cells (DC) as a result of host exposure to vanadium (here, in the form of vanadium pentoxide; V(2)O(5)) over a period of 4 weeks. All results were obtained using immunohistochemistry and flow cytometry. It is surmised that this decrease might induce a dysfunction, including possible negative selection of T-cells, which could increase the presence of autoreactive clones in the exposed host. Such an outcome could, in turn, increase the risk for development of autoimmune reactions in different organs specifically, and of autoimmune diseases in general in these V-exposed hosts.

Vinasses: characterization and treatments.

The final products of the ethanol industry are alcoholic beverages, industrial ethanol and biofuels. They are produced by the same production process, which includes fermentation and distillation of raw materials which come from plant biomass. At the end of the distillation process a waste effluent is obtained called vinasse or stillage. The direct disposal of stillages on land or in groundwater (rivers, streams or lakes), or even for the direct irrigation of crops, pollutes the environment due to their high organic contents, dissolved solids and many other compounds which are toxic or could be contaminants under certain environmental conditions. This work reviews the characterization of vinasses from different feedstock sources and the main treatments for conditioning the soluble solids of vinasses before their disposal.

Dairy bacteria remove in vitro dietary lectins with toxic effects on colonic cells.

AIMS: To assess in vitro the ability of some dairy bacteria to bind concanavalin A (Con A), peanut agglutinin (PNA) and jacalin (AIL), preventing their toxicity on mouse intestinal epithelial cells (IEC). METHODS AND RESULTS: Con A and AIL reduced significantly IEC viability in vitro, as determined by Trypan Blue dye exclusion or by propidium iodide/fluorescein diacetate/Hoescht staining. Different strains of dairy bacteria were able to remove lectins from the media. Two strains were subjected to treatments used to remove S-layer, cell wall proteins, polysaccharides and lectin-like adhesins. They were then assayed for the ability to bind dietary lectins and reduce toxicity against IEC and to adhere to IEC after interaction with lectins. Con A and AIL were removed by Propionibacterium acidipropionici and Propionibacterium freudenreichii by binding with specific sugar moieties on the bacterial surface. Removal of lectins by bacteria impaired IEC protection. Adhesion of P. acidipropionici to IEC was reduced but not abolished after binding Con A or AIL. CONCLUSIONS: Removal of Con A or AIL by dairy propionibacteria was effective to avoid the toxic effect against colonic cells in vitro. SIGNIFICANCE AND IMPACT OF THE STUDY: Consumption of foods containing these bacteria would be a tool to protect the intestinal epithelia.

Vanadium pentoxide inhalation provokes germinal center hyperplasia and suppressed humoral immune responses.

Vanadium, an important air pollutant derived from fuel product combustion, aggravates respiratory diseases and impairs cardiovascular function. In contrast, its effects on immune response are conflicting. The aim of our work was to determine if spleens of vanadium-exposed CD1 mice showed histological lesions that might result in immune response malfunction. One hundred and twelve CD-1 male mice were placed in an acrylic box and inhaled 0.02 M vanadium pentoxide (V2O5); actual concentration in chamber approximately 1.4 mg V2O5/m(3)) for 1 hr/d, twice a week, for 12 wk. Control mice inhaled only vehicle. Eight mice were sacrificed prior to the exposures. Eight control and eight V2O5-exposed mice were sacrificed 24 hr after the second exposure of each week until the 12-wk study was over. Another 8 mice that completed the 12-wk regimen were immunized with recombinant Hepatitis B surface antigen (HBsAg; three times over an 8-wk period) before sacrifice and analyses of their levels of anti-HBsAg antibody (HBSAb) using ELISA. In all studies, at sacrifice, blood samples were obtained by direct heart puncture and the spleen was removed, weighed and processed for H-E staining and quantitation of CD19 cells. The results indicated that the spleen weight of V2O5-exposed animals peaked at 9 wk (546 +/- 45 vs. 274 +/- 27 mg, p < 0.0001) and thereafter progressively decreased (321 +/- 39 mg at 12 wk, p < 0.001; control spleen = 298 +/- 35 mg). Spleens of V2O5-exposed animals showed an increased number of very large and non-clearly delimited germinal centers (that contained more lymphocytes and megakaryocytes) compared to those of control mice. In addition, their red pulp was poorly delimited and had an increase in CD19+ cells within hyperplasic germinal nodes. The mean HBsAb levels in immunized control mice were greater than that in the exposed hosts (i.e., OD = 0.39 +/- 0.03 vs. 0.11 +/- 0.05, p < 0.01). HBsAb avidity dropped to a value of 40 in V2O5-exposed animals vs. 86 in controls (p < 0.0001). We conclude that the chronic inhalation of V2O5, a frequent particle (PM(2.5)) component, induces histological changes and functional damage to the spleen, each of which appear to result in severe effects on the humoral immune response.

Matrix metalloproteinases 2 and 9 in central nervous system and their modification after vanadium inhalation.

Vanadium (V) derivatives are well-known environmental pollutants and its toxicity has been related with oxidative stress. Toxicity after vanadium inhalation on the substantia nigra, corpus striatum, hippocampus and ependymal epithelium was reported previously. The purpose of this study was to analyse the role of matrix metalloproteinases 2 (MMP-2) and 9 (MMP-9) in the changes observed in brain tissue after chronic V inhalation. Mice were exposed to vaporized, vanadium pentoxide 0.02 m in deionized water for 1 h twice a week, and killed at 1 h, 1, 2 and 4 weeks after exposure. The brain was removed and the olfactory bulb, prefrontal cortex, striatum and hippocampus were dissected and the MMP content was obtained by zymography. The results showed that MMP-9 increased in all the structures at the end of the exposure, although in the hippocampus this increment was evident after 1 week of exposure. When MMP-2 was analysed in the olfactory bulb and prefrontal cortex it remained unchanged throughout the whole exposure, while in the hippocampus it increased at week 4, while in the striatum MMP-2 increased from the second week only, through the whole experiment. These results demonstrate that V increased MMPs in different structures of the CNS and this change might be associated with the previously reported modifications, such as dendritic spine loss and neuronal cell death. The modifications in MMPs could be related with blood-brain barrier (BBB) disruption which was reported previously. Oxidative stress might also be involved in the activation of these gelatinases as part of the different mechanisms which take place in V toxicity in the CNS.

Regeneración ósea guiada utilizando membrana de óxido de aluminio en combinación con implantes oseointegrados / Guided bone regeneration using aluminum oxide membrane in combination with osseointegrated implants

La reabsorción ósea de los maxilares ha sido una de las mayorescomplicaciones al momento de rehabilitar a pacientes con implantes oseointegrados. El siguiente estudio evaluó la efectividad de la membrana de óxido de aluminio (alúmina), en la regeneración ósea de rebordes colapsados y alvéolos en los que se colocaron implantes. De un total de cinco pacientes seleccionados, se estudiaron siete sitios de los cuales tres correspondieron a un solo paciente. En cada sitio (alvéolo o reborde colapsado) se colocó un implante de titanio del sistema HIS y una membrana no biodegradable de óxido de aluminio (Allumina(R)), la cual fue retirada a las 14semanas. Todos los pacientes fueron sometidos al mismo procedimiento quirúrgico. La ganancia promedio en mm obtenidos en orden decreciente fue la siguiente: ANM: 1.7 mm, ANME: 1.6 mm, AND: 1.1 mm, AV: 1.0mm, AP: 0.5mm. Los resultados radiográficos ratificaron los resultados clínicosen cuanto a neoformación ósea, observándose además una favorable densidad ó se a periimplantaria. El análisis estadístico (basado en los resultados clínicos) t-student fue significativo para todos los parámetros evaluadoscon excepción de AP (AU)

Alveolar bone loss has been a very important cause ofcomplications in osseointegrated implant rehabilitation of edentulouspatients. This paper evaluates the effectiveness of aluminum oxidemembrane (Allumina) in the collapsed alveolar ridge where implantswere used. Seven sites were studied in 5 patients. In each of thesesites a HIS implant plus a non-biodegradable oxide aluminummembrane (Allumina®), was placed for 14 weeks. All patients weretreated with the same surgical protocol. The average gain (in mm)obtained in decreasing order was as follows: ANM: 1.7 mm, ANME:1.6 mm, AND: 1.1mm, AV: 1.0mm, AP: 0.5mm. The clinical resultswere radiographically verified and these showed bone neoformation,in addition to favorable peri-implant bone density. The t-Studentstatistical analysis based on the clinical results was significant forall the parameters evaluated with the exception of AP (AU)

Influence of probiotic vaginal lactobacilli on in vitro adhesion of urogenital pathogens to vaginal epithelial cells.

AIMS: Lactobacilli, the predominant micro-organisms of the vaginal microbiota, play a major role in the maintenance of a healthy urogenital tract by preventing the colonization of pathogenic bacteria. The aim of the present study was to assess the ability of four vaginal Lactobacillus strains, previously selected for their probiotic features, to block in vitro the adherence of three human urogenital pathogens to vaginal epithelial cells (VEC). METHODS AND RESULTS: Three types of assays were performed in order to determine the inhibitory effect of lactobacilli on adhesion of urogenital pathogens to VEC: blockage by exclusion (lactobacilli and VEC followed by pathogens), competition (lactobacilli, VEC and pathogens together) and displacement (pathogens and VEC followed by the addition of lactobacilli). Bacterial adhesion to VEC was quantified by microscopy (x1000) after Gram's stain. All the strains were able to inhibit by exclusion and competition the adhesion of Staphylococcus aureus to VEC but none was able to decrease the attachment of Escherichia coli by neither of the mechanisms assayed. Only Lactobacillus acidophillus CRL 1259 and Lactobacillus paracasei CRL 1289 inhibited the attachment of Group B streptococci (GBS) to VEC by exclusion and competition respectively. CONCLUSIONS: Lactobacillus of vaginal origin were able to inhibit the attachment of genitouropathogenic Staph. aureus and GBS to the vaginal epithelium. SIGNIFICANCE AND IMPACT OF THE STUDY: The results support the probiotic potential of these Lactobacillus strains as anti-infective agents in the vagina and encourage further studies about their capacity to prevent and manage urogenital tract infections in females.

Identification of bacterial diversity in the oyster Crassostrea gigas by fluorescent in situ hybridization and polymerase chain reaction.

AIMS: To carry out a rapid and reliable identification of bacterial diversity in the oyster Crassostrea gigas from Todos Santos Bay, México, in the current study we applied the molecular techniques of fluorescent in situ hybridization (FISH) and polymerase chain reaction (PCR). In order to reach this goal, genus and group-specific oligonucleotides targeted to 16S rDNA/rRNA were used. METHODS AND RESULTS: Oysters were collected and different tissues were analysed by means of culture-independent methodologies. In the digestive glands and gonads gamma-Proteobacteria and Gram-positive bacteria with a low G+C content, were identified as metabolically active by FISH. In the oyster gills a higher active diversity was observed, including Gram-positive bacteria with a low and high G+C content, members of the Cytophaga/Flavobacterium cluster and gamma-Proteobacteria. Consistent with FISH analysis, the amplification of 16S rDNA genes fragments with genus and group-specific oligonucleotides confirmed the presence of the same groups, as well as members of the alpha- and beta-Proteobacterias, Pseudomonas spp. and Bacillus spp. CONCLUSIONS: The combination of accurate and very easy-to-apply molecular methods allowed us to carry out a rapid screening of high bacterial diversity in oysters. SIGNIFICANCE AND IMPACT OF THE STUDY: This work is the first report about bacterial diversity in oyster tissues analysed by FISH and PCR, without using culture-dependent methods and allowed us to determine the phylogenetic diversity of the bacterial communities present in oyster cultures, including bacteria with and without metabolic activity, as well as uncultivable cells, which are generally underestimated by traditional identification.

DNA damage as an early biomarker of effect in human health.

In the last few decades the need for new approaches to assess DNA damage has been increasing due to the implications that different insults on genetic material may have on human health. In this context, the identification of how chemical agents with different mechanisms of action (i.e., antineoplastic drugs) damage DNA provides a good model to investigate some cellular and molecular mechanisms underlying the basis of genetic toxicology. The nasal epithelium is the first barrier with which environmental pollutants interact, and for this reason this epithelium can be useful as a sentinel in order to assess the interactions between the environment and the living organisms. Taking these phenomena into account and using a simple, sensitive and rapid method such as the single cell gel electrophoresis, we could obtain information and an initial approach on the DNA status. This assay in combination with other techniques that provide more information about other molecular parameters could give us a better view of the biological status of the living cell.

Helicobacter pylori: recent advances in the study of its pathogenicity and prevention.

Helicobacter pylori has acquired great importance during the last two decades, after being recognized as an important pathogen that infects a great portion of the human population. This microorganism is recognized as the main causal agent of chronic gastritis and duodenal ulcers, and it is associated with the subsequent development of gastric carcinoma. The pathogenic mechanisms of H. pylori and their relation to gastric ailments have not been clearly defined. However, at present it is well established that urease, vacuolating cytotoxin VacA, and the pathogenicity island (cag PAI) gene products, are the main factors of virulence of this organism. Thus, individuals infected with strains that express these virulence factors probably develop a severe local inflammation that may induce the development of peptic ulcer and gastric cancer. The way the infection spreads throughout the world suggests the possibility that there are multiple pathways of transmission. Due to the importance that H. pylori has acquired as a human pathogen, laboratories worldwide are attempting to develop a vaccine that confers long-term immunological protection against infection by this microorganism. Hence, the objective of this review is to present the most relevant findings of the biology of H. Pylori and its interaction with the human host.

Viability and beta-galactosidase activity of dairy propionibacteria subjected to digestion by artificial gastric and intestinal fluids.

An important criterion to consider in the selection of strains for dietary adjuncts is the ability of the microorganisms to survive the severe conditions of acidity and bile concentrations usually found in the gastrointestinal tract. In the present work, we report the effects of digestions by artificial gastric and intestinal fluids on beta-galactosidase activity and survival of four strains of dairy propionibacteria previously selected by their bile tolerance and beta-galactosidase activity. The strains were exposed to artificial gastric juice at pH values between 2 and 7 and then subjected to artificial intestinal digestion. Both viability and beta-galactosidase activity were seriously affected at pH 2. Skim milk and Emmental cheese juice exerted a protective effect on the parameters tested. The trypsin present in the intestinal fluid inactivated the enzyme beta-galactosidase in strains of Propionibacterium freudenreichii but not in Propionibacterium acidipropionici. Moreover, the presence of bile salts enhanced the beta-galactosidase activity of these strains by permeabilization of the cells during the first hour of exposure. The intestinal transit rate confirmed the permanence of the bacteria in the intestine for long enough to be permeabilized. These results suggest that P. acidipropionici would be a good source of beta-galactosidase activity in the intestine. We also propose a practical and effective in vitro method as a tool of screening and selection of potential probiotic bacteria.

[Bacterial count as an infection prognostic factor in the delayed primary closure of abdominal surgical wounds]. / La cuenta bacteriana como factor pronóstico de infección en el cierre primario tardío de heridas quirúrgicas abdominales.

STUDY OBJECTIVE: To determine the prognostic value of the soft-tissue biopsy to handle contaminated or infected surgical wounds with delayed primary closure. DESIGN: Comparative, prolective, blind and observational. PLACE: Referral tertiary care center. PATIENTS: We included 70 patients distributed in two groups: Group I: 50 patients who underwent contaminated or infected abdominal surgery; and Group II: 20 patients who underwent clean or clean contaminated abdominal surgery and developed surgical wound abscess. INTERVENTIONS: Daily cleaning and water irrigation and periodic debridement were done in all the cases; after five days (excluding infection), two tissue biopsies for quantitative culture and wound closure were performed. MEASUREMENTS AND MAIN RESULTS: In Group I, nine of 26 patients (35%) with positive culture (greater than 10(5) colony forming units/g) developed infection and none of 24 with negative culture (p less than 0.01, Fisher); the negative predictive value (nPV) was 100% and the positive predictive value (pPV) was 35%. In Group II, seven of 12 patients with positive culture and one of eight with negative culture developed infection (p less than 0.05); the nPV was 87% and the pPV was 58%. CONCLUSIONS: The biopsy of soft-tissue seems to be a helpful tool for the treatment and prognosis of infected or contaminated surgical wounds.

[Effect of gamma radiations on robertsonian translocations]. / Acción de las radiaciones gama sobre las traslocaciones robertsonianas.

Centromeric breaks and the dissociation of Robertsonian translocations have been regarded as the possible cause of a few reported cases of mosaicism. In a previous study we suggested that the dissociative phenomenon is influenced by an instability of the point of fusion, when it is located on a heterochromatic region, which appears to be a preferential mitomycin C (MMC) breakpoint. In this study lymphocytes from 6 robertsonian translocation carriers were treated with gamma rays. In one case who was a mosaic, the MMC induced a statistically significant increase in the number of cells with the dissociation. In the remaining cases, centromeric breaks or complete fissions were observed in 1.8% of the cells. In addition, the analysis of the distribution of breakage points on heterochromatic or euchromatic regions showed that almost 50% of the breaks on translocation chromosomes were located on pericentromeric heterochromatin. We postulate that the dissociation which occurs in robertsonian translocations may be caused by instability of the point of fusion since it is located on a heterochromatic region, susceptible to breakage by clastogenic agents such as MMC and gamma rays.

[The experience in dental education of Cayetano Heredia University of Peru]. / La experiencia de la universidad Peruana Cayetano Heredia en educación odontológica.

This article describes the educational experience gained in the dentistry program of Cayetano Heredia University in Peru. The programs for professional and auxiliary personnel training were drawn up after analyzing the health needs of the population and the services required to meet them, which resulted in the elaboration of an original methodology and taxonomy. Learning is an integral experience, one that takes place in the dental clinic, the hospital, and the community. The curriculum includes the following components: units for the intensive learning of clinical functions, fewer preclinical activities, clinical training with the ongoing assistance of auxiliary staff, extended interaction with marginal urban communities, rural internships, and hospital externships. A summary account is given of the gains made, the difficulties encountered, and plans for devising in-service teaching approaches that more effectively meet the needs of the community.