A biosensor capable of identifying low quantities of breast cancer cells by electrical impedance spectroscopy.

Breast cancer (BC) is a malignant disease with a high prevalence worldwide. The main cause of death is not the primary tumor, but instead the spread of tumor cells to distant sites. The aim of the present study was to examine a new method for the detection of cancer cells in aqueous medium using bioimpedance spectroscopy assisted with magnetic nanoparticles (MNP's) exposure to a constant magnetic field. The spectroscopic patterns were identified for three breast cancer cell lines. Each BC cell line represents a different pathologic stage: the early stage (MCF-7), invasive phase (MDA-MB-231) and metastasis (SK-BR-3). For this purpose, bioimpedance measurements were carried out at a certain frequency range with the aid of nanoprobes, consisting of magnetic nanoparticles (MNPs) coupled to a monoclonal antibody. The antibody was specific for the predominant cell surface protein for each cell line, which was identified by using RT-qPCR and flow cytometry. Accordingly, EpCAM corresponds to MCF-7, MUC-1 to MDA-MB-231, and HER-2 to SK-BR-3. Despite their low concentrations, BC cells could be detected by impedance spectroscopy. Hence, this methodology should permit the monitoring of circulating tumor cells (CTC) and therefore help to prevent recurrences and metastatic processes during BC treatment.

Componentes Principales mediante Espectroscopia FTIR como Técnica de Caracterización Innovadora durante la Diferenciación de Células Madre Pluripotentes a Células Pancreáticas / Principal Components by FTIR Spectroscopy as Innovative Characterization Technique during Differentiation of Pluripotent Stem Cells to Pancreatic Cells

Resumen: Dos de los grandes retos en la biología de las Células Madre (CM) y la Medicina Regenerativa, son el control en la diferenciación de estas células y asegurar la pureza de las células diferenciadas, por lo que es necesario contar con técnicas rápidas, eficientes y precisas para la caracterización de CM y su diferenciación a diferentes linajes celulares. El objetivo de este trabajo fue analizar Células Madre Pluripotentes (CMP) y Células Pancreáticas Diferenciadas (CPD) mediante espectroscopía Infrarroja por Transformada de Fourier (FTIR) y Análisis de Componentes Principales (ACP). Para ello se diferenciaron CMP a CPD, caracterizando el proceso de diferenciación a los días 0, 11, 17 y 21 mediante microscopía óptica y espectroscopia vibracional. Los espectros FTIR se analizaron con el método multivariado de ACP, utilizando su segunda derivada en las regiones de proteínas, carbohidratos y ribosas. Los resultados indican que el ACP permite caracterizar y discriminar CMP y CPD en sus diferentes etapas de diferenciación en las regiones espectrales analizadas. Con lo anterior concluimos que el ACP permite caracterizar química y estructuralmente CMP y diferentes etapas de su diferenciación en una forma rápida, precisa y no invasiva.

Abstract: Two of the greatest challenges in Stem Cells (SCs) biology and regenerative medicine, are differentiation control of SCs and ensuring the purity of differentiated cells. In this sense, fast, efficient and accurate techniques for SCs characterization and their differentiation into different cell lineages are needed. The aim of this study was to analyse Pluripotent Stem Cells (PSCs) and Differentiated Pancreatic Cells (DPCs) by Fourier Transform Infrared (FTIR) spectroscopy and Principal Component Analysis (PCA). For this purpose, we differentiated PSCs toward DPCs, characterizing the differentiation process at different stages (0, 11, 17 and 21 days) through light microscopy and vibrational spectroscopy. FTIR spectra were analysed with the multivariate method of PCA, using the second derivatives in the protein, carbohydrate and ribose regions. The results indicate that the PCA allows to characterize and discriminate PSCs and DPCs at different stages of differentiation in the analysed spectral regions. From these results, we concluded that the PCA allows the chemically and structural characterization of PSCs and the different stages of their differentiation in a fast, accurate and non-invasive way.

Evaluación de Termografía Tisular Diferenciada en Mama como Potencial Técnica para Asistir la Detección de Cáncer / Evaluation of Thermography Differentiated in Breast Tissue as Potential Technique to Assist Cancer Detection

Diversos grupos han propuesto el procesamiento de imágenes termográficas para detección de Cáncer de Mama (CaMa). Angiogénesis y vascularización dependientes del ciclo menstrual, edad e Índice de Masa Corporal (IMC) modifican la temperatura absoluta en la superficie tisular sin estar necesariamente asociadas a malignidad, en éste estudio proponemos la Termografía Tisular Diferenciada (TTD) en mama con respecto a su contralateral en espejo con el fin de observar diferencias térmicas características de malignidad. El presente trabajo evalúa la posibilidad de emplear la TTD como potencial técnica para asistir la detección de CaMa. Se muestrearon 110 mujeres voluntarias entre 40 y 60 años de edad segmentadas en dos grupos experimentales: grupo sanas (n=90) y grupo con CaMa (n=20) previamente diagnosticadas por mastografía e histopatología. Imágenes termográficas de ambas mamas fueron adquiridas con una cámara infrarroja y se estimó la TTD en relación a la mama contralateral de la misma paciente, se realizó un análisis de sensibilidad y especificidad y se comparó con el diagnóstico radiológico a través de curvas ROC tomando como referencia el diagnóstico histopatológico. La TTD en mama mostró rangos dinámicos diferenciables entre condiciones de malignidad respecto a benignidad. El análisis ROC mostró valores de sensibilidad y especificidad para el estimado TTD del 70% y 54% mientras que para el diagnóstico radiológico fue del 70% y 96%, respectivamente. La TTD muestra viabilidad técnica para asistir la detección de CaMa.

Several groups have proposed thermographic image processing for Breast Cancer (BC) detection. Angiogenesis and vascularization of menstrual cycle dependent, as well as age and Body Mass Index change the absolute temperature in the tissue surface without necessarily being associated with malignancy. We have proposed the Differentiated Tissue Thermography (DTT) in breast regarding its contralateral mirror in order to observe differences in temperature characteristics of malignancy. This study evaluates the possibility of using breast DTT as a potential technique to assist the detection of BC. We sampled 110 female volunteers between 40 and 60 years old segmented into two experimental groups: healthy group (n=90) and BC group (n=20), which were diagnosed by mammography and histopathology. Thermal images of both breasts were acquired with an infrared camera and the DTT was estimated relative to its contralateral breast in the same patient. A sensitivity and specificity analysis was developed and the DTT was compared with the radiological diagnosis by ROC curves with the histopathological report as reference. The DTT values showed distinguishable dynamic ranges between malignant and healthy conditions. ROC analysis showed sensitivity and specificity values for DTT of 70% and 54% while for the radiological diagnosis was 70% and 96% respectively. DTT showed technical viability to assist BC detection.

[Microbiological profile of infections in the Intensive Care Units of Colombia (EPISEPSIS Colombia]. / Perfil microbiológico de la Infecciones en Unidades de Cuidados Intensivos de Colombia (EPISEPSIS Colombia).

BACKGROUND AND OBJECTIVE: Valid and reliable data regarding sepsis is lacking in Colombia. Our aim was to determine the prevalence of the microorganisms in the main infections treated in Intensive Care Units (ICUs) in our country. METHODS: This is a sub-study of a prospective cohort with 10 general hospitals in Colombia during a 6-month period. The inclusion criteria were hospitalization in ICU and confirmation of infection according to the CDC definitions. Patients were classified into three groups, that is, community, hospital and intensive care, according to the site where the infection was acquired. RESULTS: A total of 826 patients were included in this analysis. Of these, 51% developed infections in the community, 5.33% in the hospital and 43.7% in intensive care unit. Overall, the most common diagnoses were pneumonia (29.54%), intra-abdominal infection (18.16%) and urinary tract infection (11.62%). The most frequent germ in community-acquired infections was E. coli -lung (16. 4%), peritoneum (57.7%), urine (55.5%), blood (22.4%)-. E. coli -peritoneum (29.3%), urine (52.9%)- also predominated in the ICU-acquired infections, except for lung and blood in which Staphylococcus aureus (32.4%) and Klebsiella pneumoniae (15.7%) were the most prevalent. Cultures were requested from 655 patients, 40% of them having received antibiotics before cultures were taken, although this did not affected the percentages of positive cultures (P=0.583). CONCLUSIONS: Pneumonia was the main cause of infection regardless of the site of acquisition. E. coli was the most prevalent germ, except in the pulmonary infections acquired in UCI in which S. aureus was the most prevalent.

Factors affecting the reproductive performance of fat-tailed ewes inseminated with laparoscopy in the late breeding season

The reproductive responses to one and two inseminations of frozen-thawed semen were compared in fat-tailed ewes which had previously been used in controlled reproduction programs aimed at estrus synchronization, multiple ovulation embryo transfer, and out of breeding season. In the trials, mature dry (n = 50) ewes in progestagen-induced estrus were inseminated 54 to 56 h after sponge removal. Half of the ewes received a second insemination 6 or 8 h later. The quality of the semen was determined by evaluating sperm motility after thawin. Association between factors included in this study and sex ratio was also investigated. The previous breeding programs effected ewes subsequent fertility and the range in lambing rates observed was from around 33% to over 75%. Higher (P < 0.05) lambing rate (56% versus 29%) and litter size (1.8 versus 1.2) indicated an advantage of two inseminations. Post-thaw evaluation of frozen semen was good indicator to achieve acceptable pregnancy rate. Sex ratio was significantly affected by the previous breeding program, one or two inseminations and post-thaw quality of frozen semen.(AU)

Factors affecting the reproductive performance of fat-tailed ewes inseminated with laparoscopy in the late breeding season

The reproductive responses to one and two inseminations of frozen-thawed semen were compared in fat-tailed ewes which had previously been used in controlled reproduction programs aimed at estrus synchronization, multiple ovulation embryo transfer, and out of breeding season. In the trials, mature dry (n = 50) ewes in progestagen-induced estrus were inseminated 54 to 56 h after sponge removal. Half of the ewes received a second insemination 6 or 8 h later. The quality of the semen was determined by evaluating sperm motility after thawin. Association between factors included in this study and sex ratio was also investigated. The previous breeding programs effected ewe’s subsequent fertility and the range in lambing rates observed was from around 33% to over 75%. Higher (P < 0.05) lambing rate (56% versus 29%) and litter size (1.8 versus 1.2) indicated an advantage of two inseminations. Post-thaw evaluation of frozen semen was good indicator to achieve acceptable pregnancy rate. Sex ratio was significantly affected by the previous breeding program, one or two inseminations and post-thaw quality of frozen semen.

Epididymal stereocilia in semen of infertile men: evidence of chronic epididymitis?

As free stereocilia in semen samples from infertile men could be related to a subclinical chronic infection of the seminal tract, we carried out a retrospective analysis of 14 files of infertile men with stereocilia in semen (group 1) and in two control groups: 30 infertile men from the same study population (group 2) and 40 fertile sperm donors (group 3). Clinical, bacteriological, sonographic and microscopic findings associated with these semen samples were compared. Epididymal cysts were found in two of 14 men in group 1 and in four of 28 in group 2. Positive semen cultures for Chlamydia trachomatis, Mycoplasma hominis or Ureaplasma urealyticum (chi(2) = 8.20; P = 0.002; OR: 7.22) and varicocele (chi(2) = 8.96; P = 0.002; OR: 2.25) were associated to the presence of free stereocilia in semen. These data suggest that a silent chronic infection of the epididymis by C. trachomatis, M. hominis, U. urealyticum and/or inflammation produced by varicocele might be the cause of stereocilia loss in the semen.

Molecular characterization of the fragile-X syndrome in the Mexican population.

The fragile X (fra-X) syndrome is the most frequent form of inherited mental retardation. Facial dysmorphism, macroorchidism and a folate-sensitive fragile site on Xq27.3 are commonly associated features. The gene causing this disorder, designated as FMR1, is X-linked and shows an unusual inheritance mode. A multistep amplification of the CGG repeats at the 5' end of the FMR1 gene has been recently identified as the cause of the fra-X syndrome. Different numbers of repeats define three gene forms (normal, premutated and mutated), whose ranges show little variation in the populations studied so far. We analyzed 18 Mexican individuals with the fra-X syndrome, 40 of their relatives (first and second degree), and 76 healthy individuals without antecedents of mental retardation. Southern blot and PCR permitted the assessment of the number of CGG repeats and the methylation state of the FMR1 gene for the normal, premutated, and mutated alleles. The results showed no statistical differences when compared with those from other populations. No cytogenetic expression of the Xq27.3 fragile site in 50% of the affected males and in all the affected and carrier females was observed. This finding emphasizes the necessity of a molecular analysis in fra-X cases and their relatives in order to provide a more adequate genetic counseling.

[The clinical study of male infertility]. / Estudio clínico de la infertilidad masculina.

Male infertility study requires systematization of clinical and paraclinical diagnostic procedures and the knowledge of frontier techniques to analyze functional capacity of human spermatozoon. The application of the various methods of assisted reproduction in male infertility treatment, should be judged with a good criterion in order to offer maximal benefit and least risk. New methods to handle gametes and standardization of existing ones, could, in the future, offer better alternatives in male infertility treatment.

Uso práctico de los índices de trauma / Trauma indexes: a practical use

Presentamos una propuesta para la aplicación práctica de metodos de cuantificacion del trauma, en el Hospital San Juan de Dios de Santa Fe de Bogota. Al ingreso del paciente al servicio de Urgencias se calcula un indice fisiologico, el Revised Trauma Score (RTS). En el postoperatorio se realiza el Injury Severity Score (ISS), con base en el Abbreviated Injury Scale (AIS), que indica la severidad anatómica de la lesion. Con los anteriores datos y la edad, se calcula el Trauma Score-Injury Severity Score (TRISS), con lo que se obtiene la Probabilidad de supervivencia (Ps). Para el paciente con trauma abdominal, se calcula el Abdominal Trauma Index (ATI), como indice pronostico de complicaciones , utilizando el Organ Injury Scaling (OIS). Al paciente con trauma torácico se le cuantifica el Penetrating Thoracic Trauma Index (PTTI), con el cual se obtiene como resultado, al sumarlo con el ATI, el Penetrating Trauma Index (PTI). Con estos indices se pretende cuantificar la severidad del trauma y lograr una buena prediccion de los resultados, lo que permite evaluar la calidad de la atencion, comparar grupos e inclusive guiar politicas administrativas.

[Index of cells obtainable from semen: indicator of fertility?]. / Indice de células recuperables del semen: indicador de fertilidad?

It has been recognized that semen analysis is not a sensible nor a specific tool for detecting infertility in the male. Its predictive value is limited by the subjectivity of manual analysis, a high variability of semen parameters in fertile men and lack of correlation between sperm characteristics and fertility indexes. In this paper we present evidence supporting the concept that calculating an index of potentially fertile cells from data obtained in a regular semen analysis might be useful for predicting fertility in the male.