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This paper describes an alternative method for the in situ synthesis of gold nanoparticles (AuNPs) with a particle size of less than 3 nm, using nanoreactors formed by reverse micelles of 1,4-bis-(2-ethylhexyl) sulfosuccinate sodium (AOT) and nanoparticle stabilization with l-cysteine, which favor the preparation of nanoparticles with size and shape control, which are homogeneously dispersed (1% by weight) on the support of titanium dioxide nanowires (TNWs). To study the activity and selectivity of the prepared catalyst (AuNPs@TNWs), an aqueous solution of 40 mM glycerol was irradiated with a green laser (λ = 530 nm, power = 100 mW) in the presence of the catalyst and O2 as an oxidant at 22 °C for 6 h, obtaining a glycerol conversion of 86% with a selectivity towards hydroxypyruvic acid (HA) of more than 90%. From the control and reactions, we concluded that the Ti-OH groups promote the glycerol adsorption on the nanowires surface and the surface plasmon of the gold nanoparticles favors the selectivity of the reaction towards the hydroxypyruvic acid.

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The preparation of catalysts can involve various sources of contamination, which can seriously affect the quality of the prepared materials. In the present work, a case of fluorine contamination in a set of catalyst samples was studied, in which using the X-Ray Photoelectron Spectroscopy (XPS) technique, it was evidenced by the F 1s signal that this element was present in the form of Teflon, since its binding energy corresponded mainly to the CF2 species. Furthermore, using the C 1s signal, it was also possible to corroborate the presence of the CF2 group, which is associated with the main component of the Teflon carbon chains. The use of this information made it possible to identify that the solvent dehydration procedure (previous step to obtaining the catalysts) could lead to contamination with Teflon since it involved various accessories with Teflon, organic solvents and high temperature; the Teflon tape and the magnetic stirrer being the possible sources of contamination.

La preparación de catalizadores puede contener diversas fuentes de contaminación, las cuales pueden afectar seriamente las propiedades de los materiales preparados. En este artículo se estudió un caso de contaminación con flúor en una serie de muestras de catalizadores. Empleando la técnica de espectroscopia fotoelectrónica de rayos X (XPS) se evidenció la presencia de flúor en la superficie de los materiales, el cual estaba asociado al polímero teflón, ya que su energía de enlace correspondía principalmente con la de la especie CF2. Además, empleando la señal C 1s, se logró corroborar la presencia de la especie CF2, el cual está asociado al componente principal de las cadenas carbonadas de teflón. El uso de la información obtenida por XPS permitió determinar que durante la deshidratación del solvente (paso previo para la obtención de los catalizadores en el cual se emplean solventes orgánicos y alta temperatura) se podría estar llevando a cabo la contaminación con teflón, ya que este componente está presente en diversos accesorios empleados en el proceso de deshidratación, siendo la cinta de teflón y el agitador magnético las posibles fuentes de contaminación.

A preparação de catalisadores pode conter diversas fontes de contaminação, as quais podem afeitar seriamente as propriedades dos materiais preparados. No presente trabalho estudou-se um caso de contaminação com flúor numa série de amostras de catalisadores. Usando a técnica da espectroscopia fotoeletrônica de raios X (XPS), evidenciou-se a presença de flúor na superfície dos materiais, o qual estava associado ao polímero Teflon, já que sua energia de ligação correspondia principalmente à da espécie CF2. Além disso, usando a sinal C 1s, foi possível corroborar a presença do grupo CF2, o qual está associado ao componente principal das cadeias carbônicas do Teflon. O uso da informação obtida por XPS permitiu determinar que durante a desidratação do solvente (passo prévio para a obtenção dos catalisadores no qual são usados solventes orgânicos e alta temperatura) tem-se a contaminação com Teflon, já que este componente está presente em diversos acessórios utilizados no processo de desidratação, sendo a fita do Teflon e o agitador magnético as possíveis fontes da contaminação.

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In this contribution, the thermodynamic analysis of α- and ß-pinene epoxide isomerization over Fe and Cu supported on MCM-41 is presented using computational chemistry and group contribution methods (GCMs). Some physical-chemical data (T c, P c, v c, Z c, ω, T b, T fus) and thermodynamic (S°298.15, C p,298.15 °, C v,298.15 °, ΔH f,298.15 °, ΔG f,298.15 °, ΔH vb °, ΔH fus, C pL) properties obtained by different GCMs are reported for several monoterpenes and monoterpenoids, which significantly contribute to the knowledge of the properties of these compounds. Density functional theory (DFT), PBE-D3/6-311G(d,p), was employed for determining the Gibbs free energy and the heat of reaction associated with the transformation of monoterpene epoxides into aldehydes, ketones, and related oxygenated compounds in the presence of different solvents and at several temperatures. The calculations were compared with available data reported and the experimental results of the catalytic reactions. The transformation of α- and ß-pinene epoxides into aldehydes appears to be more spontaneous and favorable than their transformations into alcohols in a wide range of temperatures. These results are in agreement with the experiments over Fe/MCM-41 and Cu/MCM-41, where α-pinene epoxide isomerization yields campholenic aldehyde (50-80% selectivity) as the main product. The 1.7Fe/MCM-41 material was more active in all solvents than 1.3Cu/MCM-41 for both α- and ß-pinene epoxide isomerization. However, perillyl alcohol (20-70% selectivity) was the most favored for the isomerization reaction, except when ethyl acetate was the solvent. Enthalpy and Gibbs free energy of the studied reactions estimated by both GCMs and DFT calculations did not show large differences for most of the reactions at evaluated temperatures.

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AIM: The focus of the present study was to evaluate the copper ions treatment on the viability of Mycobacterium avium subsp. paratuberculosis (MAP) and other bacterial communities in cow's milk. METHODS AND RESULTS: A copper ions treatment was evaluated in naturally contaminated cow's milk to assay MAP load and/or viability, and relative abundance of other bacterial communities. In addition, physical-chemical analyses of the milk were also performed. All analyses were carried out before and after a copper ions treatment. After copper ions treatment, pH and copper concentration markedly increased in milk; the numbers of viable MAP significantly decreased. The relative abundance of the four target phyla decreased, with the phyla Bacteroidetes and Firmicutes surviving treatment in higher proportions (4 and 2·1% of original populations, respectively). A progressively higher percentage of dead bacterial cells after 5 and 20 min copper ions treatments was found (12 and 35%, respectively). CONCLUSION: With the exception of some MAP-tolerant strains, we have once again demonstrated that copper ions have a significant inactivating effect on MAP as well as certain other bacterial communities found in naturally contaminated cow's milk. SIGNIFICANCE AND IMPACT OF THE STUDY: This study showed a significant inactivation of both MAP and other bacteria by copper ions in raw cow's milk, information that could be useful as a tool for MAP control.

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Gold nanoparticle (AuNP)-mediated photothermal therapy represents an alternative to the effective ablation of cancer cells. However, the photothermal response of AuNPs must be tailored to improve the therapeutic efficacy of plasmonic photothermal therapy (PPT) and mitigate its side effects. This study presents an alternative to ease the tuning of photothermal efficiency and target selectivity. We use laser-treated spherical and anisotropic AuNPs of different sizes and biocompatible folic acid (FA)-conjugated AuNPs (FA-AuNPs) in the well-known human epithelial cervical cancer (HeLa) cell line. We show that large AuNPs produce a more significant photothermal heating effect than small ones. The thermal response of the spherical AuNPs of 9 nm was found to reach a maximum increase of 3.0 ± 1 °C, whereas with the spherical AuNPs of 14 nm, the temperature increased by over 4.4 ± 1 °C. The anisotropic AuNPs of 15 nm reached a maximum of 4.0 ± 1 °C, whereas the anisotropic AuNPs of 20 nm reached a significant increase of 5.3 ± 1 °C in the cell culture medium (MEM). Notably, the anisotropic AuNPs of 20 nm successfully demonstrate the potential for use as a photothermal agent by showing reduced viability down to 60% at a concentration of 100 µM. Besides, we reveal that high concentrations of reactive oxygen species (ROS) are formed within the irradiated cells. In combination with stress by photothermal heating, it is likely to result in significant cell death through acute necrosis by compromising the plasma membrane integrity. Cell death and ROS overproduction during PPT were characterized and quantified by transmission electron microscopy (TEM) and confocal fluorescence microscopy with different fluorescent markers. In addition, we show that FA-AuNPs induce cell death through apoptosis by internal damage, whereas diminish the ROS formation during PPT treatment. Our findings suggest the ability of plasmon-mediated ROS to sensitize cancer cells and make them vulnerable to photothermal damage, as well as the protective role of FA-AuNPs from excessive ROS formation, whereas reducing the risk of undesired side effects due to the necrotic death pathway. It allows an improvement in the efficacy of the AuNP-based photothermal therapy and a reduction in the number of exposures to high temperatures required to induce thermal stress.

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This research aims to compare the culturing conditions for enterohepatic Helicobacter, evaluating culture media, incubation atmosphere and susceptibility to antimicrobials used to generate selective conditions. Four common media for the closely related genus Campylobacter (Columbia, Bolton, Brucella and CCDA agar), as well as the need for hydrogen in the microaerobic incubation atmosphere, were evaluated. Serial dilutions of 13 strains belonging to six species (H. apodemus, H. bilis, H. canicola, H. canis, H. equorum and Helicobacter sp.) were inoculated in each media and incubated at 37°C for 48 to 96 h using CampyGen (OXOID) and gaseous exchange (including hydrogen) in parallel. Columbia or Brucella agars were the most appropriate for culturing EHH (P < 0·05). However, there was no significant difference between the atmospheres evaluated (P = 0·13). In addition, minimal inhibitory concentration for six antibiotics showed that all isolates were resistant to trimethoprim, whereas for the rest of the antibiotics (cephalothin, cefoperazone, cefsulodin, teicoplanin and vancomycin) the inhibition range was between 8 and 64 µg ml- 1 . Our findings suggest that Columbia or Brucella media, regardless of the use of hydrogen, can be used for the EHH isolation. In addition, the concentration of antibiotics included in commercial campylobacteria supplements is suitable for EHH species recovery. SIGNIFICANCE AND IMPACT OF THE STUDY: Enterohepatic Helicobacter (EHH) infections have been associated with several diseases in humans such as acute gastroenteritis, inflammatory bowel disease and hepatobiliary diseases. Although they are frequently detected in clinical samples by molecular methods, only occasionally they are isolated using culture conditions described for the taxonomic related pathogen Campylobacter sp. This is because the optimal conditions for the isolation of EHH have not yet been described, which results in an underestimation of the prevalence and clinical importance of these emerging pathogens. Therefore, this study provides insight for culturing EHH species.

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Abstract: Introduction: It is essential that orthopaedic resident physicians be highly proficient in all aspects, considering the balance between supply, demand, need and context. Fundamental to identify the capacity and quality installed for their training in Mexico. Material and methods: Observational Study, transverse, non-probabilistic sampling-conglomerates, in two phases. The instrument has 8 domains, 57 variables and 4,867 items. 60 graduate professors of 20 states, 50 hospital sites, 22 university programs. Results: 1,038 years of experience (collective intelligence), 17 years of experience/teacher (01 to 50 years). Identified: acute pathology 30 (2 to 90%), chronic pathology 30 (5 to 96%), patients ˂ 15 years, 10 (3 to 30%), patients between 15 and 65 years, 47 (2 to 78%), patients ˃ 65 years, 20 (2 to 60%), number of beds/seat 20 (2 to 510), number of clinics 3 (1 to 48), number of surgical procedures/headquarters per year at the national level, was 960 (50 to 24,650). The national average per resident doctor is 362 surgeries/year with 1,450 surgical times/year. Conclusions: The needs and resources for the training of physicians specializing in orthopedics/traumatology are highly heterogeneous, so it should be adapted to the epidemiological needs of the region of influence, in an area of epidemiological transition. 62.2% expressed not having or have bad academic and scientific infrastructure at its headquarters, more than 50% without rotation overseas and ˃ 90% without regular scientific production.

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AIMS: A major drawback of using dairy slurry as fertilizer is that it may contains pathogens such as Mycobacterium avium subsp. paratuberculosis (MAP), and it could represent a risk to animal and public health. Thus, the aim of this study was to evaluate the fate of MAP and bacterial communities in dairy slurry after chemical treatments. METHODS AND RESULTS: Cattle slurry, naturally contaminated with MAP, was collected from a dairy herd and divided into 32 glass bottles which were assigned to eight different treatments (control, 3·0% CaO, 0·5% NaOH; 0·087%, 0·11% and 0·14% H2 SO4 ; and 1·0 and 2·5% KMnO4 ). Treated dairy slurry samples were evaluated at 0, 1, 3, 7, 15, 30 and 60-days following treatment application for viable MAP and dairy slurry pH, and in addition temperature in this material was monitored continuously. Bacterial counts were estimated at each sampling time. A Bayesian zero-inflated Poisson mixed model was fitted to assess the effect of each treatment on the count of MAP cells. Model results indicated that only the 3·0% CaO treatment had a statistically important negative effect on MAP counts during the study period. For most treatments, MAP was undetectable immediately after chemical treatment but re-appeared over time, in some replicates at low concentrations. However, in those cases MAP counts were not statistically different than the control treatment. Regarding the fate of the other bacterial populations, the Firmicutes phylum was the dominant population in the un-treated slurry while Clostridia class members were among the most prevalent bacteria after the application of most chemical treatments. CONCLUSION: Only 3% CaO treatment had a statistically important negative effect on MAP viability in cattle slurry. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides evidence of MAP partial control in dairy slurry. This information should be considered as a best management practice to reduce MAP and other pathogens for slurry management on dairy farms.

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WHAT IS KNOWN AND OBJECTIVE: Glibenclamide is a prescribed glucose-lowering medication for diabetes, but there are interindividual variations in the therapeutic response. In this cross-sectional study, the aim was to explore the association of genetic variants in CYP2C9, ABCC8, KCNJ11 and TCF7L2 with good glycaemic control in Mexican type 2 diabetes (T2D) treated with glibenclamide. METHODS: Patients with T2D receiving treatment with glibenclamide or glibenclamide plus metformin were included. Patients with A1C ≤ 7% were considered to have good glycaemic control, whereas patients with A1C ≥ 8% were considered having poor glycaemic control. Genotyping was performed by real-time PCR using TaqMan probes for the genetic variants. Association was performed by calculating OR with 95% confidence intervals (95% CI). For the multivariate analysis, a multiple logistic regression was performed including the confounding variables age, exercised, BMI, glibenclamide dose, time with T2D and concomitant metformin. RESULTS AND DISCUSSION: Four hundred and four patients were included in the study, median age of the participants was 50 years (IQR 11.0), the median time with disease was 6 years (IQR 8.0), 118 (29.2%) were men, and 243 (60.1%) received glibenclamide in combination with metformin. CYP2C9*3 variant was associated with good glycaemic control (OR = 2.747 [95% CI, 1.194-6.324]), whereas the variants, CYP2C9*2, TCF7L2 rs7903146 and rs12255372, ABCC8 rs757110 and KCNJ11 rs5219, were not. In the multivariate analysis, the CYP2C9*3 variant maintained its association (OR = 2.779 [95% CI, 1.142-6.763]). WHAT IS NEW AND CONCLUSION: The findings suggest that CYP2C9*3 genetic variant independently contributes to good glycaemic control of patients with type 2 diabetes treated with glibenclamide.

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BACKGROUND: Histological diagnosis of a clinically suspected nonmelanoma skin cancer (NMSC) is recommended before treatment. For NMSC, concordance between the histological subtype of the preoperative biopsy and the excision specimen of basal cell carcinoma (BCC) has been reported to range from 10% to 81%. No large study on the concordance between NMSC histology seen in a preoperative biopsy with the following tumour specimen from Mohs micrographic surgery (MMS) has been performed in a Latin American population. OBJECTIVE: The aim of this study was to analyse and compare the histological subtype of the incisional biopsies reviewed by the dermatopathologist with the histological subtype of the tumour specimen obtained during MMS interpreted by the dermatopathologist and the Mohs surgeon. METHODS: A retrospective analysis of 320 NMSC was performed. The interobserver correlation was based on kappa values. RESULTS: The mean weighted kappa value between the preoperative NMSC biopsy and intraoperative histological subtype of the tumour specimen from MMS analysed by the Mohs surgeon and the dermatopathologist was 0.22 and 0.24, respectively. The correlation in the histologic subtype of the intraoperative tumour specimen from MMS that was interpreted by the dermatopathologist and Mohs surgeon was 0.58. CONCLUSIONS: Dermatologists need to be aware of the limited value of incisional biopsies to accurately diagnose the histological subtype of a NMSC. The concordance rate in the histological diagnosis of the tumour specimens that were obtained from MMS between the Mohs surgeon and the dermatopathologist is moderate. However, the correlation is low compared with incisional biopsy subtypes.

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El hipotiroidismo subclínico se define como una concentración sérica elevada de tirotropina (TSH), con T4 libre normal. En el embarazo, se ha descrito efectos deletéreos tales como riesgo aumentado de aborto espontáneo y déficit cognitivo del niño en mujeres con esta condición; además, se debe considerar la posible progresión a hipotiroidismo clínico. Se ha planteado el rol de la autoinmunidad mediante la presencia de anticuerpos anti-tiroperoxidasa (AntiTPO), describiéndose este como factor de riesgo para desenlaces adversos. No se ha comprobado la utilidad del tamizaje universal con TSH, siendo el enfoque actualmente el estudio de pacientes de riesgo. El tratamiento se inicia según los resultados de la cuantificación deTSH y AntiTPO, siendo el fármaco de elección la levotiroxina.El seguimiento es conmediciones deTSH.

Sub-clinical hypothyroidism is defined to be raised plasma thyrotropin (TSH) with normal levels of free T4. Detrimental effects such as increased abortion risk and newborns with cognitive deficit have been reported in pregnancies with this condition. Possible progression to clinical hypothyroidism must be considered. A possible auto-immune mechanism mediated by anti-thyroperoxidase (AntiPO) has been postulated where AntiPO should be considered a risk factor for adverse outcomes. Universal screening using TSH has not been found to be of use and at present only high risk women are screened. Women are treated with levothyroxine, the dose depending on the TSH andAntiPO levels, and follow up is done bymonitoringTSHlevels.

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Nierembergia linariifolia var. linariifolia ha sido sospechada históricamente como planta tóxica en algunas regiones del noroeste de Argentina. Se administró una dosis de 10 g de materia seca de planta molida/kg de peso, a tres cabras adultas mediante el empleo de sonda nasogástrica. Otros tres animales permanecieron como grupo control y recibieron heno de alfalfa. Las cabras que recibieron la planta, presentaron signos clínicos de cólico abdominal entre las 7 y 45 horas post-administración. Ninguno de los animales murió y todos se recuperaron totalmente a las 72 horas de iniciado el ensayo. Nierembergia linariifolia var. linariaefolia demostró tener efectos tóxicos a nivel gastrointestinal a la dosis administrada, aunque no se observaron daños más severos.

The species Nierembergia linariifolia var. linariifolia has been historically incriminated as toxic for animals in northwestern Argentina. A dose of 10 g of ground dry matter / kg of live weight was administered to three adult goats by the use of a nasogastric tube. Another three animals remained as "control group", and receiving alfalfa hay. The goats that received the plant presented clinical signs of abdominal colic between 7 and 45 hours post-administration. None of the animals died and all recovered fully within 72 hours of initiation of the test. Nierembergia linariifolia var. linariaefolia showed to have toxic effects at the gastrointestinal level at the dose administered, although no severe damage was observed.

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Resumen: Introducción: La fractura del tobillo es una de las lesiones más frecuentes del sistema musculoesquelético; existen estudios de población que reportan un aumento en la incidencia de estas fracturas a partir de los años 70 asociado al incremento en la difusión a través de los medios de las actividades deportivas de contacto. Las fracturas trans- y suprasindesmales afectan la sindesmosis y, de no tratarse adecuadamente, dejarán inestabilidad articular. El tratamiento más común es la colocación de un tornillo; existe controversia en la altura a la que este se debe colocar con respecto a la línea articular tibioastragalina. Material y método: Estudio descriptivo, observacional, retrospectivo y transversal de expedientes clínicos y radiográficos de pacientes operados de fractura bimaleolar; se les dividió en dos grupos: aquellos con el tornillo transindesmal a 2 o 2.5 cm y aquellos con el tornillo a 3.5 cm o más proximal. Se recolectaron 34 casos en total (grupo A: 16 pacientes; grupo B: 18), 22 del sexo masculino y 12 del femenino, de edades entre 19 y 45 años. Resultados: Se aplicó la escala funcional de Olerud-Molander y se midió el claro medial del tobillo para considerar el grado de reducción de la sindesmosis. Se compararon los resultados de ambos grupos. Discusión: El sitio de localización del tornillo de situación a 2.0 cm presentó un porcentaje de 75% de estabilidad articular y 25% de inestabilidad articular, la funcionalidad articular fue relativamente menor en comparación con la colocación del tornillo a 3.5 cm, donde se logró una estabilidad articular de 83.3% y 16.3% de inestabilidad articular.

Abstract: Background: Ankle fractures are one of the most frequent lesions of the musculoskeletal system; there are studies that report an increase in the incidence of these fractures starting in the 1970s, associated with the increased media outreach of sporting activities. Supra- and transyndesmal fractures often lead to injury of the syndesmosis, which, if not treated properly, will leave joint instability. The most common treatment is the placement of a transyndesmal screw; there is controversy on the height in which it should be located with regard to the distal tibial joint line. Material and method: A descriptive, observational, retrospective and transversal study with clinical and radiographic records of patients operated on bimalleolar fractures; they were divided into two groups: those with the transyndesmal screw at 2 or 2.5 cm and those with the screw at 3.5 cm or more proximal. There was a total of 34 cases (group A: 16 patients; group B: 18), 22 male and 12 female, aged between 19 and 45 years. Results: We applied the Olerud-Molander ankle score for the clinical evaluation and measured the radiographic medial space of the ankle to consider the degree of reduction. The results in both groups were compared. Discussion: The location of the screw at 2.0 cm presented a percentage of 75% of joint stability and 25% of joint instability, the joint functionality was relatively smaller in comparison to the placement of the screw at 3.5 cm, with which we achieved a joint stability of 83.3% and 16.3% of joint instability.

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Heterophyllaea pustulata Hook. f. (Rubiaceae) is a phototoxic plant. It grows in the Andean area of northwest of Argentina, and it causes significant economic losses in the livestock. This plant induces dermal lesions by photosensitization probably due to its content of photosensitizing anthraquinones. This paper describes an outbreak of poisoning in Corriedale sheepfold, which had an incidence of 49%. Ear skin biopsies and blood samples were collected of six affected animals. Liver enzymes remained within the reference limits. Histopathologically, a deep necrotizing dermatitis was identified in all samples. H. pustulata was identified in the areas of grazing. Anthraquinone concentration in leaves was 0.84% p/p, expressed as rubiadin. All findings allow us to conclude that the diagnosis is a primary photosensitization. Huge regional economic losses could be attributed to H. pustulata poisoning, although its toxicity has been little studied.

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BACKGROUND: Ankle fractures are one of the most frequent lesions of the musculoskeletal system; there are studies that report an increase in the incidence of these fractures starting in the 1970s, associated with the increased media outreach of sporting activities. Supra- and transyndesmal fractures often lead to injury of the syndesmosis, which, if not treated properly, will leave joint instability. The most common treatment is the placement of a transyndesmal screw; there is controversy on the height in which it should be located with regard to the distal tibial joint line. MATERIAL AND METHOD: A descriptive, observational, retrospective and transversal study with clinical and radiographic records of patients operated on bimalleolar fractures; they were divided into two groups: those with the transyndesmal screw at 2 or 2.5 cm and those with the screw at 3.5 cm or more proximal. There was a total of 34 cases (group A: 16 patients; group B: 18), 22 male and 12 female, aged between 19 and 45 years. RESULTS: We applied the Olerud-Molander ankle score for the clinical evaluation and measured the radiographic medial space of the ankle to consider the degree of reduction. The results in both groups were compared. DISCUSSION: The location of the screw at 2.0 cm presented a percentage of 75% of joint stability and 25% of joint instability, the joint functionality was relatively smaller in comparison to the placement of the screw at 3.5 cm, with which we achieved a joint stability of 83.3% and 16.3% of joint instability.

INTRODUCCIÓN: La fractura del tobillo es una de las lesiones más frecuentes del sistema musculoesquelético; existen estudios de población que reportan un aumento en la incidencia de estas fracturas a partir de los años 70 asociado al incremento en la difusión a través de los medios de las actividades deportivas de contacto. Las fracturas trans- y suprasindesmales afectan la sindesmosis y, de no tratarse adecuadamente, dejarán inestabilidad articular. El tratamiento más común es la colocación de un tornillo; existe controversia en la altura a la que este se debe colocar con respecto a la línea articular tibioastragalina. MATERIAL Y MÉTODO: Estudio descriptivo, observacional, retrospectivo y transversal de expedientes clínicos y radiográficos de pacientes operados de fractura bimaleolar; se les dividió en dos grupos: aquellos con el tornillo transindesmal a 2 o 2.5 cm y aquellos con el tornillo a 3.5 cm o más proximal. Se recolectaron 34 casos en total (grupo A: 16 pacientes; grupo B: 18), 22 del sexo masculino y 12 del femenino, de edades entre 19 y 45 años. RESULTADOS: Se aplicó la escala funcional de OlerudMolander y se midió el claro medial del tobillo para considerar el grado de reducción de la sindesmosis. Se compararon los resultados de ambos grupos. DISCUSIÓN: El sitio de localización del tornillo de situación a 2.0 cm presentó un porcentaje de 75% de estabilidad articular y 25% de inestabilidad articular, la funcionalidad articular fue relativamente menor en comparación con la colocación del tornillo a 3.5 cm, donde se logró una estabilidad articular de 83.3% y 16.3% de inestabilidad articular.

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BACKGROUND: The most common etiological agents in periprosthetic infections are Escherichia coli and Staphylococcus aureus. The frequency of these infections are found in knee replacement with 0.68 to 1.60% compared to the hip with 0.67 to 2.4%. OBJECTIVE: To identify what are the most common etiologic agents in periprosthetic infections in elderly patients with primary hip and knee surgery. MATERIAL AND METHODS: An observational study, transverse and retrospective case series was performed in a period from June 2011 to December 2014, patients over 60 years with a diagnosis of periprosthetic infection by two positive cultures with antibiograma. RESULTS: 62 patients were evaluated 59.7% were infections of knee and hip 40.3%, 59% were infections by Escherichia coli and Staphylococcus aureus 22%. The best sensitivity reported antibiotic trimethoprim-sulfamethoxazole was 40.3%. The largest penicillin G resistance 32.2%. CONCLUSION: The most common causative agents were Escherichia coli and Staphylococcus aureus.

Los agentes etiológicos más frecuentes en las infecciones periprotésicas son Escherichia coli y Staphylococcus aureus. La frecuencia de estas infecciones se presenta en el reemplazo articular de rodilla de 0.68 a 1.60% en comparación con el de cadera de 0.67 a 2.4%.

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Resumen: Antecedentes: Los agentes etiológicos más frecuentes en las infecciones periprotésicas son Escherichia coli y Staphylococcus aureus. La frecuencia de estas infecciones se presenta en el reemplazo articular de rodilla de 0.68 a 1.60% en comparación con el de cadera de 0.67 a 2.4%. Objetivo: identificar cuáles son los agentes etiológicos más frecuentes en infecciones periprotésicas en adultos mayores y en pacientes con cirugía primaria de cadera y rodilla. Material y métodos: Se realizó un estudio observacional, transversal y retrospectivo, tipo serie de casos en un período comprendido de Junio de 2011 a Diciembre de 2014, se incluyeron pacientes mayores de 60 años con diagnóstico de infección periprotésica mediante dos cultivos positivos con antibiograma. Resultados: Se evaluaron 62 pacientes, 59.7% presentaron infecciones de rodilla y 40.3% de cadera, 59% fueron infecciones por Escherichia coli y 22% por Staphylococcus aureus. El antibiótico que mejor sensibilidad reportó fue trimetoprim-sulfametoxazol (40.3% )y el de mayor resistencia fue penicilina G (32.2%). Conclusión: Los agentes etiológicos más frecuentes fueron Escherichia coli y Staphylococcus aureus.

Abstract: Background: The most common etiological agents in periprosthetic infections are Escherichia coli and Staphylococcus aureus. The frequency of these infections are found in knee replacement with 0.68 to 1.60% compared to the hip with 0.67 to 2.4%. Objective: To identify what are the most common etiologic agents in periprosthetic infections in elderly patients with primary hip and knee surgery. Material and methods: An observational study, transverse and retrospective case series was performed in a period from June 2011 to December 2014, patients over 60 years with a diagnosis of periprosthetic infection by two positive cultures with antibiograma. Results: 62 patients were evaluated 59.7% were infections of knee and hip 40.3%, 59% were infections by Escherichia coli and Staphylococcus aureus 22%. The best sensitivity reported antibiotic trimethoprim-sulfamethoxazole was 40.3%. The largest penicillin G resistance 32.2%. Conclusion: The most common causative agents were Escherichia coli and Staphylococcus aureus.

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