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The search for the minimum information required for an organism to sustain a cellular system network has rendered both the identification of a fixed number of known genes and those genes whose function remains to be identified. The approaches used in such search generally focus their analysis on coding genomic regions, based on the genome to proteic-product perspective. Such approaches leave other fundamental processes aside, mainly those that include higher-level information management. To cope with this limitation, a non-genocentric approach based on genomic sequence analysis using language processing tools and gene ontology may prove an effective strategy for the identification of those fundamental genomic elements for life autonomy. Additionally, this approach will provide us with an integrative analysis of the information value present in all genomic elements, regardless of their coding status.

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Kluyveromyces marxianus is a non-conventional yeast with outstanding physiological characteristics and a high potential for lignocellulosic ethanol production. However, achieving high ethanol productivity requires overcoming several biotechnological challenges due to the cellular inhibition caused by the inhibitors present in the medium. In this work, K. marxianus SLP1 was adapted to increase its tolerance to a mix of inhibitory compounds using the adaptive laboratory evolution strategy to study the adaptation and stress response mechanisms used by this non-Saccharomyces yeast. The fermentative and physiological parameters demonstrated that the adapted K. marxianus P8 had a better response against the synergistic effects of multiple inhibitors because it reduced the lag phase from 12 to 4 h, increasing the biomass by 40% and improving the volumetric ethanol productivity 16-fold than the parental K. marxianus SLP1. To reveal the effect of adaptation process in P8, transcriptome analysis was carried out; the result showed that the basal gene expression in P8 changed, suggesting the biological capability of K. marxianus to activate the adaptative prediction mechanism. Similarly, we carried out physiologic and transcriptome analyses to reveal the mechanisms involved in the stress response triggered by furfural, the most potent inhibitor in K. marxianus. Stress response studies demonstrated that P8 had a better physiologic response than SLP1, since key genes related to furfural transformation (ALD4 and ALD6) and stress response (STL1) were upregulated. Our study demonstrates the rapid adaptability of K. marxianus to stressful environments, making this yeast a promising candidate to produce lignocellulosic ethanol. KEY POINTS: • K. marxianus was adapted to increase its tolerance to a mix of inhibitory compounds • The basal gene expression of K. marxianus changed after the adaptation process • Adapted K. marxianus showed a better physiological response to stress by inhibitors • Transcriptome analyses revealed key genes involved in the stress response.

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Significant risks to human health have been associated with chronic exposure to low doses of pesticides, a situation which may be frequent among agricultural workers. In this context, and regarding the agricultural-based economy of central Chile, we aimed to explore the genotoxic damage in agricultural workers and reproductive risk among women in rural and urban areas of Curicó, a traditional agricultural district in Chile. Hence, we sampled a group of rural agricultural workers associated with pesticide management (n = 30) and an urban unexposed group (n = 30). Our results showed that the agricultural workers had higher micronuclei frequencies (MN: ß = 13.27; 95% CI low = 11.08, CI high = 15.47) and women had a 40-fold higher risk of reproductive problems (OR = 40.32; 95% CI low = 2.60, CI high = 624.31) than the unexposed group. The factor analysis of mixed data (FAMD) showed that neither the sex nor smoking habits appear to define the ordination of the data. Nevertheless, the exposure level did segregate them in the multidimensional space (explained variance: 35.38% dim-1; 18.63% dim-2). This pilot study highlights the higher risks of biological conditions negatively associated with the health of agricultural workers.

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Objetivo: Comparar el protocolo que incluye la secuencia tridimensional SPACE-3D con el protocolo convencional en el estudio imagenológico por resonancia magnética (RM) del paciente con dolor lumbar. Metodología: Se realizó un estudio prospectivo de pruebas diagnósticas, en el que se tomaron imágenes por RM de la columna lumbar de 40 pacientes utilizando un protocolo convencional y otro protocolo que incluyera una secuencia volumétrica (SPACE-3D) en conjunto con secuencia axial con información T1 y sagital STIR, en un resonador de 1,5T. Las imágenes fueron interpretadas por dos radiólogos de manera independiente, empleando tanto el protocolo convencional como el protocolo que incluía la secuencia volumétrica, con un mes de diferencia. Se compararon ambos protocolos calculando la sensibilidad y la especificidad con el intervalo de confianza (IC 95 %), se consideró significación estadística un valor de p≤ 0,05 utilizando la prueba de Chi-cuadrado. Se evaluaron para ambas técnicas variables como presencia o no de artefactos, protrusión/extrusión discal, estrechez del canal neural central, receso lateral o foramen de emergencia radicular, radiculopatía. Se calculó la concordancia inter e intraobservador utilizando el índice Kappa con un IC 95 %. Resultados: Se encontró que el protocolo que incluye la secuencia SPACE-3D presenta rendimiento diagnóstico similar (no inferior) frente al protocolo con las secuencias convencionales para las variables evaluadas; igualmente, se detectaron los hallazgos anormales, lo cual permitió un estudio completo y un diagnóstico en menor tiempo. Conclusiones: El rendimiento diagnóstico del protocolo que incluye la secuencia volumétrica SPACE-3D es similar (no inferior) al protocolo con las secuencias convencionales utilizadas en RM de columna lumbar y acorta el tiempo total del estudio

Objective: To compare the protocol that includes the three-dimensional SPACE-3D sequence with the conventional protocol in the magnetic resonance imaging (MRI) study of patients with low back pain. Methods: A prospective study of diagnostic tests was carried out, in which MR images of the lumbar spine were taken from 40 patients using a conventional protocol and another protocol that included a volumetric sequence (SPACE-3D) in conjunction with axial T1 and sagittal STIR sequences, in a 1.5T resonator. The images were interpreted by two radiologists independently, both the conventional protocol and the protocol that included the volumetric sequence, one month apart. Both protocols were compared, calculating the sensitivity and specificity with the confidence interval (CI 95%), a value of p ≤0.05 using the Chi-square test was considered statistically significant. Variables such as the presence or absence of artifacts, disc protrusion/extrusion, narrowing of the central neural canal, lateral recess or root emergence foramen, and presence of radiculopathy, among others, were evaluated for both techniques. Inter- and intra-observer agreement was calculated using the Kappa index with a 95% CI. Results: it was found that the protocol that included the SPACE-3D sequence presents similar diagnostic performance (not inferior) when compared to the protocol with the conventional sequences for the variables evaluated, similarly, abnormal findings were detected, which allowed a complete study and diagnosis in less time. Conclusions: The diagnostic performance of the protocol that includes the SPACE-3D volumetric sequence is similar (not inferior) to the protocol with conventional sequences used in MRI of the lumbar spine and shortens the total study time.

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Carbapenemase production in Enterobacterales clinical isolates is a global threat. Multi-drug resistant Klebsiella pneumoniae harboring carbapenemases are a major concern among the hospital settings in Latin America. Aim: The aim of this study was to analyze the genetic relatedness between three isolates of K. pneumoniae recovered from one patient in the same bacteriological round on the same day, which exhibited different susceptibility profiles to carbapenems (CP) and to colistin (Col). Isolates' profiles were as follows (susceptible-S/resistant-R): CPS/ColR, CPR/ColR, and CPR/ColS. Pulse-field gel electrophoresis, multilocus sequence typing, and whole genome sequencing were performed. Conjugation assays were carried out and PCR determination in transconjugants (Tcs) was made for: blaCTX-M-groups, blaNDM, blaKPC, blaTEM, qnr alleles, aac(6')Ib-cr, ermB, and plasmid incompatibility groups (Inc). Results: All isolates belonged to the same clone, to ST258 and harbored blaCTX-M-14, blaCTX-M-15, qnrA1, qnrB1, aac(6')Ib-cr, and wzi154 (capsule-locus KL107). One isolate had additional wzi gene, wzi109 (capsule-locus KL36). In CPR isolates, the pattern was explained for blaNDM-1 or blaNDM-1/blaKPC-2 presence, and in ColR for IS5-like element insertion in mgrB at different positions. Co-mobilization of blaNDM-1/qnrA1 was associated to a different plasmid Inc (A/C-FII) in both blaNDM-1 donors. Mobilization of blaCTX-M-14 was related to IncI1 in one donor. Conclusion: These findings highlight the potential plasticity of ST258 K. pneumoniae clone. To the best of our knowledge, this is the first description of blaNDM-1/blaKPC-2-producing K. pneumoniae ST258 in Latin America.

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BACKGROUND: Learning assessment has great impact in students' achievement. However, it is one of the least intervened and researched areas in higher education institutions, all over the world. AIM: To compare the written tests applied to students of three health science undergraduate programs (Speech Therapy, Medical Technology and Nursing), with the written tests of three programs of other areas (Business and Administration, Psychology and Bioengineering). MATERIAL AND METHODS: Comparisons were done using the Authentic Assessment Model's indicators. Also, the magnitude of the change in these variables was evaluated in these two groups of undergraduate programs, after the participation of the teachers in a training program based on this model. A quantitative and repeated measurements design was used. Nineteen teachers participated (nine from medical sciences and 10 from other areas), who drafted 88 written tests before the intervention (which involved 1,318 items) and 93 written tests (that grouped 1,051 items) after it. Items were analyzed using a Hierarchical Lineal Model (HLM), controlling the tests' and the teachers' effects. RESULTS: Both groups of undergraduate programs use multiple choice items with a higher frequency, although there were differences in the rest of the items. Also, HLM analysis showed that these programs differed in their changes after the intervention. Health science programs had less improvement in changing the kind of items used, but improved more in Authentic Assessment indicators. CONCLUSIONS: Written tests improved after an intervention aiming to improve the teachers' skills to prepare such tests.

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Background: Learning assessment has great impact in students' achievement. However, it is one of the least intervened and researched areas in higher education institutions, all over the world. Aim: To compare the written tests applied to students of three health science undergraduate programs (Speech Therapy, Medical Technology and Nursing), with the written tests of three programs of other areas (Business and Administration, Psychology and Bioengineering). Material and Methods: Comparisons were done using the Authentic Assessment Model's indicators. Also, the magnitude of the change in these variables was evaluated in these two groups of undergraduate programs, after the participation of the teachers in a training program based on this model. A quantitative and repeated measurements design was used. Nineteen teachers participated (nine from medical sciences and 10 from other areas), who drafted 88 written tests before the intervention (which involved 1,318 items) and 93 written tests (that grouped 1,051 items) after it. Items were analyzed using a Hierarchical Lineal Model (HLM), controlling the tests' and the teachers' effects. Results: Both groups of undergraduate programs use multiple choice items with a higher frequency, although there were differences in the rest of the items. Also, HLM analysis showed that these programs differed in their changes after the intervention. Health science programs had less improvement in changing the kind of items used, but improved more in Authentic Assessment indicators. Conclusions: Written tests improved after an intervention aiming to improve the teachers' skills to prepare such tests.

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Resumen El auge de las imágenes diagnósticas, en especial de la tomografía computarizada multidetector ha permitido que entidades poco conocidas sean detectadas con relativa frecuencia. Inicialmente, se creía que todos los pacientes con neumatosis intestinal padecían enfermedades abdominales graves o presentaban complicaciones que requerían un manejo quirúrgico inmediato, pero al conocer mejor esta entidad, en parte gracias al aumento en el número de tomografías realizadas en la práctica diaria, se ha demostrado que la neumatosis intestinal también puede presentarse en pacientes asintomáticos o asociada a entidades benignas. Es importante conocer los signos y síntomas que ayudan a diferenciar las formas benignas de neumatosis de aquellas que ponen en peligro la vida del paciente y requieren manejo quirúrgico. Presentamos dos casos de neumatosis intestinal y una revisión de la literatura que ayudarán a aclarar la presentación por imágenes y etiología de esta entidad poco conocida.

Abstract Penumatosis intestinalis is a clinical condition that has been increasingly detected in recent years with the escalating use of computed tomography for abdominal imaging. Previously, it was thought that all the patients cursing with penumatosis intestinalis had life threatening conditions that required immediate surgical treatment. With the increased detection of this radiologic entity, benign causes have been described for example the cystic pneumatosis intestinalis, which in the mayority of times is an isolated finding and does not require surgery. It is important to recognize the signs and symptoms that help differentiate the benign forms, from those that are life-threatening conditions and require surgery. We report two cases of pneumatosis cystoides and a review of the literature that will illustrate the imaging findings and etiology of this rare entity.

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Los angiosarcomas de la mama son tumores raros que conforman menos del 1 % de las neoplasias mamarias. Estos tumores pueden desarrollarse de forma primaria o secundaria y se han descrito 219 casos en la literatura mundial desde el primer caso informado por Schmidt en 1887. A continuación se presentan dos casos de angiosarcoma primario de la mama y sus principales características en los diferentes métodos diagnósticos.

Angiosarcomas are rare tumors that make up less than 1% of breast cancers. These tumors may develop in a primary or secondary form, and 219 cases have been reported in the literature since the first case described by Schmidt in 1887. Here we present two cases of primary angiosarcoma of the breast and its main features in different imaging modalities

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En los pacientes con VIH es frecuente la tuberculosis (TB) extrapulmonar; sin embargo, la incidencia de afectación esofágica es baja. Se requiere de una alta sospecha clínica para realizar un adecuado enfoque diagnóstico y para identificar al Mycobacterium TB como agente causal de infección. Los estudios por imagen, como la radiografía convencional de tórax, el esófagograma, la tomografía computarizada multicorte (TCM) y la endoscopia digestiva superior aportan información basada en hallazgos específicos que pueden orientar hacia el diagnóstico de TB ganglionar y esofágica. Sirven como guía para la toma de muestras de tejidos y la realización de estudios confirmatorios de presencia del bacilo, como las pruebas moleculares y cultivos. Se reseñan 2 casos de pacientes jóvenes, de sexo masculino, con diagnóstico de VIH/sida C3 con coinfección por TB, quienes desarrollaron compromiso ganglionar mediastinal y esofágico, con perforación secundaria y fístula mediastínica.

Extrapulmonary tuberculosis (TB) is frequent in HIV patients; nevertheless, the incidence of esophageal involvement is low and high clinical suspicion is required for a proper diagnostic approach in order to identify Mycobacterium TB as a causative agent of infection. Imaging studies such as conventional chest radiography, esophagogram, multislice computed tomography (MCT), and upper endoscopy provide information based on specific findings that can lead to the diagnosis of TB. They serve as a guide for tissue sampling and confirmatory molecular tests and cultures. This article presents two cases of young male patients diagnosed with HIV/AIDS C3 and co-infected with TB, who developed esophageal and mediastinal lymph node involvement, with secondary perforation and mediastinal fistula.

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La enfermedad fistulosa perianal es una entidad inflamatoria crónica que afecta el canal anal y los espacios perianales. Las fístulas anales presentan gran morbilidad y recurrencia. Para definir el tipo de tratamiento quirúrgico o médico, evitar recurrencias y complicaciones como la incontinencia fecal, es importante una adecuada caracterización y clasificación de las fístulas mediante la resonancia magnética (RM). Actualmente la RM es el estudio imaginológico con mayor sensibilidad diagnóstica debido a su alta resolución anatómica para definir las estructuras del canal anal y demostrar el trayecto fistuloso con sus complicaciones (abscesos y trayectos secundarios).

Fistulous perianal disease is an inflammatory entity that affects the anal canal and perianal spaces. Anal fistulas represent important morbidity and recurrence for patients. For the planning of surgical treatment, preventing recurrences and complications like fecal incontinence, a proper characterization and classification of fistulas with magnetic resonance must be done. Currently, magnetic resonance is the imaging modality with greatest diagnostic sensitivity due to its high anatomical resolution in defining structures like the anal canal and fistulous tracts with its complications (abscesses, secondary paths).

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Los hamartomas mesenquimales de la pared torácica son lesiones raras que generalmente se presentan en la infancia temprana y que se manifiestan como una masa que deforma la pared torácica y puede acompañarse de disnea. Hasta el momento, en la literatura mundial se ha informado de 100 casos, aproximadamente. Los diferentes métodos de imagen, como la radiografía de tórax, la tomografía computarizada (TC) o la resonancia magnética son útiles para realizar el diagnóstico; sin embargo, la TC es más útil en el diagnóstico, porque logra demostrar el origen óseo y las calcificaciones intralesionales. Es importante conocer las características imaginológicas de este tipo de lesiones, ya que pueden ser fácilmente confundidas con un tumor maligno.

Mesenchymal hamartomas of the chest wall are extremely rare lesions that usually affect children and newborns and whose most common manifestation is a large mass that deforms the chest wall and can cause dyspnea. Up to this date, approximately 100 cases have been reported worldwide in the literature. Different imaging methods such as chest X-ray, computed tomography (CT) or magnetic resonance imaging (MRI) are useful for diagnosis; nevertheless, CT is the best in diagnostic aid because it manages to demonstrate bony origin and intralesional calcifications. It is important to identify the imaginological features of such lesions because they can easily be mistaken for a malignant tumor.

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In order to determine the occurrence of AbaR-type genomic island in multidrug resistant Acinetobacter baumannii (MDRAb) strains circulating in Argentina, Uruguay, and Chile, we studied 51 MDRAb isolates recovered from several hospitals over 30 years. AbaR-type genomic resistance islands were found in 36 MDRAb isolates since 1986 till now. MLST technique allowed us to identify the presence of four different Clonal Complexes (109, 104, 119, 113) among the positive AbaR-type island positive strains. This is the first description of AbaR-type islands in the CC104 and CC113 that are the most widespread Clonal Complexes in Argentina. In addition, PCR mapping exposed different arrays to those previously described, evidencing the plasticity of this island. Our results evidence a widespread distribution of the AbaR-type genomic islands along the time in the MDRAb population, including the epidemic global clone 1 (GC1) as well as different clonal complexes to those already described in the literature.

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Los colgajos de perforantes se han constituido en el escalón reconstructivo de mayor refinamiento quirúrgico por sus beneficios al dejar mínima morbilidad en las áreas donantes y permitir el tallado de los tejidos más precisos a los defectos a reconstruir, permitiendo al mismo tiempo la transferencia de varios tipos de tejidos, constituyéndose así en una herramienta versátil para casos complejos, con defectos tridimensionales y necesidades tisulares específicas. El presente artículo realiza una revisión de los aspectos clínicos, así como la presentación de pacientes manejados con esta opción que dentro del campo de la microcirugía reconstructiva se posiciona como la primera elección al contemplar las diferentes posibilidades de tratamiento.

Perforator flaps have turned into the reconstructive step with the highest surgical refinement because of its benefits by limiting the donor site morbidity and allowing more accurate tissue graving in the defects to be reconstructed while allowing the transference of several types of tissues, thus becoming a versatile tool for complex cases with tridimensional defects and specific tissue needs. This article reviews the clinical features as well as the presentation of patients managed through this option, which, in the field of reconstructive microsurgery, has been positioned as the leading election when the different possibilities of treatment are considered.

Os retalhos de perfurantes constituemse no degrau reconstrutivo de maior refinamento cirúrgico por seus benefícios ao deixar mínima morbilidade nas áreas doadoras e permitir esculpir os tecidos de forma mais precisa no momento de corrigir defeitos e reconstruir, permitindo ao mesmo tempo a transferência de vários tipos de tecidos, constituindose assim em uma ferramenta versátil para casos complexos, com defeitos tridimensionais e necessidades tissulares específicas. O presente artigo faz uma revisão dos aspectos clínicos, bem como a apresentação de pacientes tratados com esta opção que dentro do campo da microcirurgia reconstrutiva se posiciona como a primeira escolha ao considerar as diferentes possibilidades de tratamento.

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Two Pb(II)-resistant bacteria isolated from a soil containing 2,500 mg/kg of Pb were identified by 16S rRNA sequencing analysis as Delftia sp. and designated as 3C and 6C. Both isolates grew at a Pb(II) concentration of 62 mg/L and at the stationary phase showed a Pb(II)-sorption capability of 10 ± 1.5 (3C) and 5 ± 0.8 (6C) mg/g of biomass. Biochemical properties related to heavy metal resistance and plant growth promotion were analyzed and compared with the Cr(VI)-resistant plant growth-promoting Delftia sp. JD2, previously reported by our group. Both isolates and JD2 were resistant to Cr(VI), Pb(II) and many antibiotics, produced siderophores and the phytohormone indole-3-acetic, and showed clover growth-promoting activity in greenhouse conditions. Interestingly, the occurrence of integron class 1 was shown in all isolates. Our results add to previous reports and suggest that bacteria of the genus Delftia could be consider as good candidates for the design of technologies for cleaning up contaminated environments and/or the production of biofertilizers.

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Eleven clinical class 1 integron-containing Pseudomonas aeruginosa isolates from Australia and Uruguay were investigated for the genomic locations of these elements. Several novel class 1 integrons/transposons were found in at least four distinct locations in the chromosome, including genomic islands. These elements seem to be undergoing successful dispersal by lateral gene transfer since integrons were identified across several lineages and more than one clonal line.

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Acinetobacter baumannii has emerged as a serious problem in the hospital environment at a global scale. Previous results from our laboratory showed a high frequency of class 2 integrons in A. baumannii strains from Argentina regarding the low rate of this element in A. baumannii isolates from the rest of the world. To reveal the current epidemiology of class 2 integrons, a molecular surveillance analyzing 78 multidrug resistant (MDR) A. baumannii isolates from Argentina and Uruguay was performed, exposing the presence of class 2 integron in the 36.61% of the isolates. Class 2 integron characterization showed that the typical Tn7::In2-7 array was present in 26 out of 27 intI2 positive isolates. All intI2 positive isolates contained at least one of the Tn7 transposition genes. In addition, we identified that 18 intI2 positive isolates possessed the Tn7::In2-7 within the attTn7 site. The molecular typing evidenced that clones I and IV that do not belong to widespread European clones I and II were found among the intI2 positive isolates. Our results exposed the widely dissemination of class 2 integron among MDR A. baumannii isolates from Argentina and Uruguay, also showing the persistence of two novel clones in our region, which could explain in part the high frequency of class 2 integron found in our region.

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Con el fin de analizar la presencia de metalo-ß-lactamasas en nuestro medio, se incluyeron en este estudio aislamientos de Pseudomonas aeruginosa causantes de infecciones nosocomiales en un centro hospitalario del Uruguay, en el período comprendido entre abril y setiembre de 2008. En un aislamiento se detectó la presencia del gen codificante de la metalo-ß-lactamasa VIM-2 asociado a un integrón de clase 1 y del gen codificante de una ß-lactamasa de espectro extendido CTX-M-2. Esta es la primera comunicación de la presencia de los genes blaCTX-M-2 y blaVIM-2 en un mismo aislamiento de P. aeruginosa. A pesar de que las carbapenemasas ya han sido ampliamente documentadas en varias partes del mundo, esta es la primera comunicación de una metalo-ß-lactamasa adquirida con actividad carbapenemasa en bacterias patógenas encontradas en el Uruguay.

VIM-2 metallo-ß-lactamase gen detection in a class 1 integron associated to blaCTX-M-2 in a Pseudomonas aeruginosa clinical isolate in Uruguay: first communication. In order to analyze the presence of metallo-ß-lactamase in our country, we included in this study Pseudomonas aeruginosa isolates causing nosocomial infections in a hospital from Uruguay. The presence of a metallo-ß-lactamase VIM-2 in a class 1 integron and of an extended spectrum -lactamase CTX-M-2 was detected in one isolate. This is the first report of both genes, blaCTX-M-2 and blaVIM-2,in the same P. aeruginosa isolate. Although carbapenemases have been extensively documented in the world, this is the first report of an acquired metallo-ß-lactamase with carbapenemase activity in pathogenic bacteria in Uruguay.

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In order to analyze the presence of metallo-ß-lactamase in our country, we included in this study Pseudomonas aeruginosa isolates causing nosocomial infections in a hospital from Uruguay. The presence of a metallo-ß-lactamase VIM-2 in a class 1 integron and of an extended spectrum -lactamase CTX-M-2 was detected in one isolate. This is the first report of both genes, bla(CTX-M-2) and bla(VIM-2),in the same P. aeruginosa isolate. Although carbapenemases have been extensively documented in the world, this is the first report of an acquired metallo-ß-lactamase with carbapenemase activity in pathogenic bacteria in Uruguay.

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