Molecular diagnosis of cystic fibrosis by RNA obtained from nasal epithelial cells.

BACKGROUND: The diagnosis of cystic fibrosis (CF) is established when characteristic clinical signs are coupled with biallelic CFTR pathogenic variants. No previously reported non-canonical splice site variants have to be considered as variants of uncertain significance unless their effect on splicing has been validated. METHODS: Two variants identified by next-generation sequencing were evaluated. We assayed their effects on splicing employing RNA analysis and real-time expression quantification from RNA obtained from the nasal epithelial cells of a patient with clinically suspected CF and of two patients with milder phenotypes (CFTR-related disorders). RESULTS: The variant c.164+2dup causes skipping of exon 2 (p.(Ser18_Glu54del)) and exon 2 plus 3 (p.(Ser18Argfs*16)) in CFTR mRNA. Exon 2 expression in the patient heterozygous for c.164+2dup was decreased to 7 % of the exon 2 expression in the controls. The synonymous variant c.1584G>A causes a partial skipping of exon 11. The exon 11 expression in the two patients heterozygous for this variant was 22 % and 42 % of that of the controls, respectively. CONCLUSION: We conclude that variant c.164+2dup affects mRNA processing and can be considered a CF-causing variant. The results of the functional assay also showed that the p.(Glu528=) variant, usually categorized as a neutral variant based on epidemiological data, partially affects mRNA processing in our patients. This finding would allow us to reclassify the variant as a CFTR-related variant with incomplete penetrance. RNA obtained from nasal epithelial cells is an easy and accurate tool for CFTR functional studies in patients with unclassified splice variants.

Infarto pulmonar: signos que no debemos dejar pasar en TC de tórax sin contraste / Pulmonary infarction: the signs that we must not miss in chest CT without contrast

Resumen El infarto pulmonar (IP) resulta de la oclusión de las arterias pulmonares distales que generan isquemia, hemorragia y finalmente necrosis del parénquima pulmonar, siendo la causa más frecuente la embolia pulmonar (EP). El diagnóstico oportuno de IP permite el inicio precoz del tratamiento y el respectivo manejo de sostén, disminuyendo así la morbimortalidad asociada. El objetivo de esta revisión es remarcar la importancia de identificar aquellos signos, que en la tomografía computada (TC) sin contraste son altamente sensibles y específicos para el diagnóstico de IP. La TC de alta resolución constituye el método que más información aporta, pudiendo observar signos clásicos de IP como la opacidad en forma de cuña, opacidad con radiolucencia central y el signo del vaso nutricio; así como signos con alto valor predictivo negativo para IP, como la opacidad consolidativa con broncograma aéreo, sugestivo de otras patologías, ya sean infecciosas o tumorales.

Abstract Pulmonary infarction (PI) results from occlusion of the distal pulmonary arteries leading to ischemia, hemorrhage, and necrosis of the pulmonary parenchyma. The most common cause of pulmonary infarction is pulmonary embolism (PE). Early diagnosis of PI allows early initiation of treatment and supportive care, thus reducing the associated morbidity and mortality. This review aims to highlight the importance of identifying signs that are highly sensitive and specific for the diagnosis of PE even without IV contrast. High-resolution computed tomography (CT) is the method that provides the most information, as it observes classic signs of PI such as wedge-shaped opacity, central lucencies in peripheral consolidation, and the feeding vessel sign, as well as signs with high negative predictive value such as consolidating opacity with air bronchogram that are suggestive of other pathologies, whether infectious or tumoural.

High-performance bioelectronic tongue for the simultaneous analysis of phenols, sugars and organic acids in wines.

BACKGROUND: Electronic tongues have been widely used to analyze wines. However, owing to the complexity of the matrix, the problem is not completely solved and further improvements are required. RESULTS: A high-performance potentiometric bioelectronic tongue (bio-ET) specifically devoted to the assessment of wine components is presented. The novelty of this system is due to two innovative approaches. First, the improved performance is obtained through the use of potentiometric biosensors based on carboxylated polyvinyl chloride (PVC) membranes, where enzymes (glucose oxidase, tyrosinase, laccase, and lyase) specific to compounds of interest are linked covalently. Second, the performance is further enhanced by introducing electron mediators (gold nanoparticles or copper phthalocyanine) into the PVC membrane to facilitate the electron transfer process. Individual sensors exposed to target analytes (glucose, catechol, cysteine, or tartaric acid) show a linear behavior, with limits of detection in the region of 10-4 mol L-1 for all the compounds analyzed, with excellent reproducibility (coefficient of variation lower than 3%). Sensors combined to form a bio-ET show excellent capabilities. Principal component (PC) analysis can discriminate monovarietal white wines (PC1 77%; PC2 15%) and red wines (PC1 63%; PC2 30%). Using partial least squares, the bio-ET can provide information about chemical parameters, including glucose, total polyphenols, total anthocyanins, free and total sulfur dioxide, total acidity, and pH with R2 between 0.91 and 0.98 in calibration and between 0.89 and 0.98 in validation. CONCLUSIONS: This advanced instrument is able to assess the levels of seven parameters in a single measurement, providing an advantageous method to the wine industry. © 2023 Society of Chemical Industry.

Cation leak through the ATP1A3 pump causes spasticity and intellectual disability.

ATP1A3 encodes the α3 subunit of the sodium-potassium ATPase, one of two isoforms responsible for powering electrochemical gradients in neurons. Heterozygous pathogenic ATP1A3 variants produce several distinct neurological syndromes, yet the molecular basis for phenotypic variability is unclear. We report a novel recurrent variant, ATP1A3(NM_152296.5):c.2324C>T; p.(Pro775Leu), in nine individuals associated with the primary clinical features of progressive or non-progressive spasticity and developmental delay/intellectual disability. No patients fulfil diagnostic criteria for ATP1A3-associated syndromes, including alternating hemiplegia of childhood, rapid-onset dystonia-parkinsonism or cerebellar ataxia-areflexia-pes cavus-optic atrophy-sensorineural hearing loss (CAPOS), and none were suspected of having an ATP1A3-related disorder. Uniquely among known ATP1A3 variants, P775L causes leakage of sodium ions and protons into the cell, associated with impaired sodium binding/occlusion kinetics favouring states with fewer bound ions. These phenotypic and electrophysiologic studies demonstrate that ATP1A3:c.2324C>T; p.(Pro775Leu) results in mild ATP1A3-related phenotypes resembling complex hereditary spastic paraplegia or idiopathic spastic cerebral palsy. Cation leak provides a molecular explanation for this genotype-phenotype correlation, adding another mechanism to further explain phenotypic variability and highlighting the importance of biophysical properties beyond ion transport rate in ion transport diseases.

Characterization of mutant versions of the R-RAS2/TC21 GTPase found in tumors.

The R-RAS2 GTP hydrolase (GTPase) (also known as TC21) has been traditionally considered quite similar to classical RAS proteins at the regulatory and signaling levels. Recently, a long-tail hotspot mutation targeting the R-RAS2/TC21 Gln72 residue (Q72L) was identified as a potent oncogenic driver. Additional point mutations were also found in other tumors at low frequencies. Despite this, little information is available regarding the transforming role of these mutant versions and their relevance for the tumorigenic properties of already-transformed cancer cells. Here, we report that many of the RRAS2 mutations found in human cancers are highly transforming when expressed in immortalized cell lines. Moreover, the expression of endogenous R-RAS2Q72L is important for maintaining optimal levels of PI3K and ERK activities as well as for the adhesion, invasiveness, proliferation, and mitochondrial respiration of ovarian and breast cancer cell lines. Endogenous R-RAS2Q72L also regulates gene expression programs linked to both cell adhesion and inflammatory/immune-related responses. Endogenous R-RAS2Q72L is also quite relevant for the in vivo tumorigenic activity of these cells. This dependency is observed even though these cancer cell lines bear concurrent gain-of-function mutations in genes encoding RAS signaling elements. Finally, we show that endogenous R-RAS2, unlike the case of classical RAS proteins, specifically localizes in focal adhesions. Collectively, these results indicate that gain-of-function mutations of R-RAS2/TC21 play roles in tumor initiation and maintenance that are not fully redundant with those regulated by classical RAS oncoproteins.

Programmed Death-Ligand 1 (PD-L1) as Immunotherapy Biomarker in Breast Cancer.

Breast cancer constitutes the most common malignant neoplasm in women around the world. Approximately 12% of patients are diagnosed with metastatic stage, and between 5 and 30% of early or locally advanced BC patients will relapse, making it an incurable disease. PD-L1 ligation is an immune inhibitory molecule of the activation of T cells, playing a relevant role in numerous types of malignant tumors, including BC. The objective of the present review is to analyze the role of PD-L1 as a biomarker in the different BC subtypes, adding clinical trials with immune checkpoint inhibitors and their applicable results. Diverse trials using immunotherapy with anti-PD-1/PD-L1 in BC, as well as prospective or retrospective cohort studies about PD-L1 in BC, were included. Despite divergent results in the reviewed studies, PD-L1 seems to be correlated with worse prognosis in the hormone receptor positive subtype. Immune checkpoints inhibitors targeting the PD-1/PD-L1 axis have achieved great response rates in TNBC patients, especially in combination with chemotherapy, making immunotherapy a new treatment option in this scenario. However, the utility of PD-L1 as a predictive biomarker in the rest of BC subtypes remains unclear. In addition, predictive differences have been found in response to immunotherapy depending on the stage of the tumor disease. Therefore, a better understanding of tumor microenvironment, as well as identifying new potential biomarkers or combined index scores, is necessary in order to make a better selection of the subgroups of BC patients who will derive benefit from immune checkpoint inhibitors.

Update on systemic treatment in early triple negative breast cancer.

Triple negative breast cancer (TNBC) is a heterogeneous disease representing about 15% of all breast cancers. TNBC are usually high-grade histological tumors, and are generally more aggressive and difficult to treat due to the lack of targeted therapies available, and chemotherapy remains the standard treatment. There is a close relationship between pathological complete response after chemotherapy treatment and higher rates of disease-free survival and overall survival. In this review of systemic treatment in early triple negative breast cancer, our purpose is to analyze and compare different therapies, as well as to highlight the novelties of treatment in this breast cancer subtype.

Symptomatic heterozygous X-Linked myotubular myopathy female patient with a large deletion at Xq28 and decrease expression of normal allele.

X-linked myotubular myopathy (XLMTM; OMIM 310400) is a centronuclear congenital muscular disorder of X-linked recessive inheritance. Although female carriers are typically asymptomatic, affected heterozygous females have been described. Here, we describe the case of a sporadic female patient with suspicion of centronuclear myopathy and a heterozygous large deletion at Xq28 encompassing the MAMLD1, MTM1, MTMR1, CD99L2, and HMGB3 genes. The deletion was first detected using a custom next generation sequencing (NGS)-based multigene panel and finally characterized by comparative genomic hybridization array and multiplex ligation probe assay techniques. In this patient we have confirmed, by MTM1 mRNA quantification, a MTM1 gene expression less than the expected 50 percent in patient muscle. The significant 20% reduction in MTM1 mRNA expression in muscle, precludes low level of the normal myotubularin protein as the cause of the phenotype in this heterozygous female. We have also found that BIN1 expression in patient muscle biopsy was significantly increased, and postulate that BIN1 expression will be increased in XLMTM patient muscle as an attempt to maintain muscle function.

Targeting cytoskeletal phosphorylation in cancer.

Phosphorylation of cytoskeletal proteins regulates the dynamics of polymerization, stability, and disassembly of the different types of cytoskeletal polymers. These control the ability of cells to migrate and divide. Mutations and alterations of the expression levels of multiple protein kinases are hallmarks of most forms of cancer. Thus, altered phosphorylation of cytoskeletal proteins is observed in most cancer cells. These alterations potentially control the ability of cancer cells to divide, invade and form distal metastasis. This review highlights the emergent role of phosphorylation in the control of the function of the different cytoskeletal polymers in cancer cells. It also addresses the potential effect of targeted inhibitors in the normalization of cytoskeletal function.

Lack of Association of IL6 polymorphism with the susceptibility to Chagas disease in Latin American populations.

The aim of the present study was to analyze IL6 rs1800795 genetic variant in the susceptibility to Trypanosoma cruzi infection and in the development of chronic Chagas cardiomyopathy (CCC), in five independent Latin American cohorts. A total of 3,087 individuals from Latin American countries (Argentina, Bolivia, Peru, and two cohorts from Colombia) were studied. In all cohorts, patients were classified as seropositive for T. cruzi antigens (n= 1,963) and seronegative (n= 1,124). Based on clinical evaluation, the seropositive patients, were classified as CCC (n= 900) and asymptomatic (n= 1,063). No statistically significant differences in the frequency of IL6 rs1800795 between seropositive and seronegative, or between CCC and asymptomatic patients, were found. Furthermore, after the meta-analysis no statistically significant differences were observed. Our results do not support a contribution of IL6 rs1800795 genetic variant in the susceptibility to the infection and the development of chronic Chagas cardiomyopathy in the studied populations.

Efficacy of the Benznidazole+Posaconazole combination therapy in parasitemia reduction: An experimental murine model of acute Chagas

Abstract INTRODUCTION: Benznidazole (BZL) and Nifurtimox (NFX) are the pharmacological treatment for acute phase Chagas Disease (CD); however, therapy resistance and residual mortality development remain important unresolved issues. Posaconazole (POS) has shown a trypanocidal effect in vivo and in vitro. Thus, this study aimed at comparing the T. Cruzi parasitic load-reducing effect of the combination of BZL+POS against that of monotherapy with either, during acute phase CD, in an experimental murine model. METHODS Nineteen Wistar rats were randomly allocated to four groups and inoculated with the trypomastigotes of T. cruzi strain´s JChVcl1. The rats were administered anti-parasites from day 20-29 post-infection. The Pizzi and Brener method was used for parasitemia measurement. Longitudinal data analysis for the continuous outcome of repeated measures was performed using parasitemia as the outcome measured at days 20, 22, 24, 27, and 29 post-infection. RESULTS All four groups had similar parasitic loads (p=0.143) prior to therapy initiation. Among the three treatment groups, the BZL+POS (n=5) group showed the highest mean parasitic load reduction (p=0.000) compared with the control group. Likewise, the BZL+POS group rats showed an earlier therapeutic effect and were the only ones without parasites in their myocardial samples. CONCLUSIONS: Treatment of acute phase CD with BZL+POS was more efficacious at parasitemia and myocardial injury reduction, compared with monotherapy with either.

Phosphatidylinositol Monophosphates Regulate Optimal Vav1 Signaling Output.

Phosphatidylinositol-5 phosphate (PI5P) and other mono-phosphoinositides (mono-PIs) play second messenger roles in both physiological and pathological conditions. Despite this, their intracellular targets and mechanisms of action remain poorly characterized. Here, we show that Vav1, a protein that exhibits both Rac1 GDP/GTP exchange and adaptor activities, is positively modulated by PI5P and, possibly, other mono-PIs. Unlike other phospholipid-protein complexes, the affinity and specificity of the Vav1-lipid interaction entail a new structural solution that involves the synergistic action of the Vav1 C1 domain and an adjacent polybasic tail. This new regulatory layer, which is not conserved in the Vav family paralogs, favors the engagement of optimal Vav1 signaling outputs in lymphocytes.

Microfilament-coordinated adhesion dynamics drives single cell migration and shapes whole tissues.

Cell adhesion to the substratum and/or other cells is a crucial step of cell migration. While essential in the case of solitary migrating cells (for example, immune cells), it becomes particularly important in collective cell migration, in which cells maintain contact with their neighbors while moving directionally. Adhesive coordination is paramount in physiological contexts (for example, during organogenesis) but also in pathology (for example, tumor metastasis). In this review, we address the need for a coordinated regulation of cell-cell and cell-matrix adhesions during collective cell migration. We emphasize the role of the actin cytoskeleton as an intracellular integrator of cadherin- and integrin-based adhesions and the emerging role of mechanics in the maintenance, reinforcement, and turnover of adhesive contacts. Recent advances in understanding the mechanical regulation of several components of cadherin and integrin adhesions allow us to revisit the adhesive clutch hypothesis that controls the degree of adhesive engagement during protrusion. Finally, we provide a brief overview of the major impact of these discoveries when using more physiological three-dimensional models of single and collective cell migration.

HLA-Matched Donor-Recipient Combinations and Kidney Transplant Probabilities in a Specific Colombian Population / Compatibilidad HLA donante-receptor y probabilidades de trasplante renal en una población colombiana / Compatibilidade HLA doador-receptor e probabilidades de transplante renal em uma população colombiana

Introduction: In Colombia, despite the fact that kidney transplants are the most common type of transplant surgery, a great number of transplanted patients do not achieve the desired Human Leucocyte Antigen (HLA) compatibility. HLA compatibility plays an important role in graft survival; patients with matched-HLA have a lower chance of graft-versus-host disease and graft rejection. Objective: To determine the probability of finding an HLA-matched donor-recipient pairs according to HLA−A, −B and −DRB1 frequencies in a specific Colombian population. Materials and methods: The study included a total of 484 unrelated individuals (61 donors and 423 recipients) from the HLA registry. HLA alleles were determined by polymerase chain reaction sequence with specific indicators. Results: HLA-A*02, -A*24, -B*35 and -DRB1*04 alleles showed the highest minimum allele frequency (>10%). In addition, HLA-A*24-B*35-DRB1*04 was the most frequent extended haplotype in both donors and recipients (7.38% and 6.76%, respectively). Our experimental evidence showed that the maximum chance of finding at least one HLA allele-matched kidney is 20.3% for a patient with the most frequent extended haplotype, whereas for patients with rare or non-common haplotypes this probability is rather unlikely. Discussion: In terms of probability, the chance of finding an HLA matched kidney donor/recipients in our region is low. This is due, at least in part, to the higher number of alleles and a the lower donation rate. Therefore, to define the HLA profile of a population is important for establishing transplantation programs and alternative strategies in the kidney donation and allocation processes.

Introducción: en Colombia, el trasplante renal es el más común, sin embargo, un gran número de personas trasplantadas no tiene la compatibilidad HLA deseada. Esta compatibilidad es importante en la supervivencia del trasplante; pacientes con HLA-compatible tienen un menor chance de rechazo o desarrollo de la enfermedad injerto frente a hospedero. Objetivo: determinar la probabilidad de encontrar compatibilidad HLA receptor-donante acorde con las frecuencias en población colombiana de HLA−A, −B y −DRB1. Materiales y métodos: el estudio incluyó 484 individuos no relacionados (61 donantes y 423 receptores) con registro de HLA. Los alelos HLA fueron determinados por reacción en cadena de la polimerasa con iniciadores específicos. Resultados: los alelos HLA-A*02, -A*24, -B*35 y -DRB1*04 tuvieron la frecuencia alélica mínima más alta (>10%). El alelo extendido HLA-A*24-B*35-DRB1*04 fue el más frecuente, en donantes y receptores (7,38% y 6,76%, respectivamente). Nuestro análisis mostró que el máximo chance de encontrar un riñón con un alelo HLA compatible es de 20,3% para un paciente con el haplotipo extendido más frecuente, mientras para pacientes con haplotipos raros o no comunes esta probabilidad es mínima. Conclusión: en términos de probabilidad, el chance de encontrar en nuestra región, un riñón con compatibilidad HLA entre donante/receptor es baja. Por lo menos, en parte, es debido al alto número de alelos y a la baja tasa de donación. Por lo tanto, determinar el perfil de HLA de una población es importante para establecer programas de trasplante y estrategias alternativas en donación de riñones y procesos de asignación.

Introdução: Na Colômbia, o transplante renal é o mais comum, no entanto, um grande número de pessoas transplantadas não tem a compatibilidade HLA desejada. Esta compatibilidade é importante na supervivência do transplante; pacientes com HLA-compatível têm uma menor chance de rejeição ou desenvolvimento da enfermidade enxerto versus hospedeiro. Objetivo: determinar a probabilidade de encontrar compatibilidade HLA receptor-doador conforme às frequências em população colombiana de HLA-A, -B e -DRB1. Materiais e métodos: O estudo incluiu 484 indivíduos não relacionados (61 doadores e 423 receptores) com registro de HLA. Os alelos HLA-A*02, -A*24, -B*35 e -DRB1*04 tiveram a frequência alélica mínima mais alta (>10%). Resultados: O alelo estendido HLA-A*24-B*35-DRB1*04 foi o mais frequente, em doadores e receptores (7,38% e 6,76%, respectivamente). Nossa análise mostrou que a máxima chance de encontrar um rim com um alelo HLA compatível é de 20,3% para um paciente com o haplótipo estendido mais frequente, enquanto para pacientes com haplótipos raros ou não comuns esta probabilidade é mínima. Conclusões: em termos de probabilidade, a chance de encontrar em nossa região, um rim com compatibilidade HLA entre doador/receptor é baixa. Pelo menos em parte, é devido ao alto número de alelos e à baixa taxa de doação. Pelo tanto, determinar o perfil de HLA de uma população é importante para estabelecer programas de transplante e estratégias alternativas em doação de rins e processos de atribuição.

Current advances in the generation of human iPS cells: implications in cell-based regenerative medicine.

Over the last few years, the generation of induced pluripotent stem cells (iPSCs) from human somatic cells has proved to be one of the most potentially useful discoveries in regenerative medicine. iPSCs are becoming an invaluable tool to study the pathology of different diseases and for drug screening. However, several limitations still affect the possibility of applying iPS cell-based technology in therapeutic prospects. Most strategies for iPSCs generation are based on gene delivery via retroviral or lentiviral vectors, which integrate into the host's cell genome, causing a remarkable risk of insertional mutagenesis and oncogenic transformation. To avoid such risks, significant advances have been made with non-integrative reprogramming strategies. On the other hand, although many different kinds of somatic cells have been employed to generate iPSCs, there is still no consensus about the ideal type of cell to be reprogrammed. In this review we present the recent advances in the generation of human iPSCs, discussing their advantages and limitations in terms of safety and efficiency. We also present a selection of somatic cell sources, considering their capability to be reprogrammed and tissue accessibility. From a translational medicine perspective, these two topics will provide evidence to elucidate the most suitable combination of reprogramming strategy and cell source to be applied in each human iPSC-based therapy. The wide variety of diseases this technology could treat opens a hopeful future for regenerative medicine. Copyright © 2015 John Wiley & Sons, Ltd.

An Update on Human Stem Cell-Based Therapy in Parkinson's Disease.

CDATA[Parkinson's disease (PD) is the second most common neurodegenerative disorder after Alzheimer's disease and it is characterized by the progressive loss of dopaminergic neurons of the substantia nigra pars compacta (SNpc). Current pharmacological treatments for PD are only symptomatic and unfortunately there is still no cure for this disorder. Stem cell technology has become an attractive option to investigate and treat PD. Indeed, transplantation of fetal ventral mesencephalic cells into PD brains have provided proof of concept that cell replacement therapy can be beneficial for some patients, greatly improving their motor symptoms. However, ethical and practical aspects of tissue availability limit its widespread clinical use. Hence, the need of alternative cell sources are based on the use of different types of stem cells. Stem cell-based therapies can be beneficial by acting through several mechanisms such as cell replacement, trophic actions and modulation of inflammation. Here we review recent and current remarkable clinical studies involving stem cell-based therapy for PD and provide an overview of the different types of stem cells available nowadays, their main properties and how they are developing as a possible therapy for PD treatment.

Laboratory genetic-based reference values for cholinesterase activity in a Colombian population: A step forward in personalized diagnostics / Valores de referencia basados en el contexto genético de la actividad enzimática de la colinesterasa en una población colombiana: un paso hacia el diagnóstico personalizado

Introduction: The determination of cholinesterase (ChE) activity has been commonly applied in the biomonitoring of exposure to organophosphate and carbamate pesticides. However, ChE activity is influenced by genetic factors. Integrating genotype and phenotype information in clinical laboratory tests would increase the accuracy of the reference values in well-defined populations. Objective: To establish genetic-based reference values for acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activity in a Colombian population. Materials and methods: A total of 397 healthy adults from Bucaramanga were included in the study. AChE and BChE activities were measured in blood samples by potentiometry and spectrophotometry, respectively. Genotyping for ACHE rs17880573 and BCHE rs1803274 was performed using the TaqMan allelic discrimination assay. The statistical analyses to obtain the reference values were performed with the MedCalc® software. Results: Allele frequencies were 10.58% for rs17880573 A and 8.82% for rs1803274 A. People with genotypes rs1803274 AA and AG showed a reduction of 20.69% and 10.92% respectively in mean BChE activity compared to people with genotype GG. No significant differences were identified in AChE activity between rs17880573 alleles or genotypes. In the overall sample, the corresponding reference values were as follows: for AChE activity, 0.62-0.98 D pH/h and for BChE activity, 4796.3-10321.1 U/L for people carrying the allele rs1803274A and 5768.2-11180.4 U/L for people carrying the genotype rs1803274 GG. Conclusion: We strongly recommend using these genetic-based reference values for ChE enzymes in our well-defined population in daily clinical practice.

Introducción. La determinación de la actividad enzimática de la colinesterasa se utiliza comúnmente en la vigilancia biológica de la exposición a pesticidas organofosforados y carbamatos. Sin embargo, los factores genéticos afectan la actividad de la colinesterasa, por lo que la integración de la información sobre genotipos y fenotipos en las pruebas de laboratorio clínico, incrementaría la precisión de los valores de referencia. Objetivo. Establecer los valores de referencia basados en el contexto genético para la actividad enzimática de la acetilcolinesterasa (AChE) y la butirilcolinesterasa (BChE), en una población colombiana. Materiales y métodos. Se incluyeron 397 adultos sanos. La actividad de la acetilcolinesterasa y la de la butirilcolinesterasa, se determinaron en muestras de sangre por potenciometría y espectrofotometría, respectivamente. Los genotipos de los ACHE rs17880573 y BCHE rs1803274 se obtuvieron mediante el ensayo TaqMan y los valores de referencia se estimaron con el programa MedCalc®. Resultados. La frecuencia alélica fue de 10,58 % para rs17880573 A y de 8,82 % para rs1803274 A. Las personas con los genotipos rs1803274 AA y AG, mostraron una reducción en el promedio de la actividad de la butirilcolinesterasa de 20,69 % y de 10,92 %, respectivamente, comparados con aquellas con el genotipo GG. No se encontraron diferencias significativas en la actividad de la acetilcolinesterasa con respecto a los alelos y genotipos del rs17880573. Los valores de referencia determinados para esta población fueron de 0,62-0,98 D pH/h para acetilcolinesterasa y de 4796,3-10321,1 U/L para butirilcolinesterasa, en las personas portadoras del alelo rs1803274 A, y de 5768,2-11180,4 U/L, en las portadoras del genotipo rs1803274 GG. Conclusión. Se recomienda el uso de estos valores de referencia basados en el contexto genético para las colinesterasas, en la práctica clínica diaria en esta población.

Molecular identification and genotyping of Streptococcus mutans from saliva samples of children in Medellin, Colombia / Identificación molecular y genotipificación de Streptococcus mutansde muestras de saliva de niños de Medellín, Colombia

Abstract Introduction and objective: Tooth decay is one of the most prevalent infectious diseases of the oral cavity. The aim of this study was to determine the prevalence of Streptoccocus mutans and its genotypes in saliva samples from 6 and 7 year old children with and without dental caries. Materials and methods: Forty seven saliva samples were obtained from 6-7 year-old children, randomly selected from a Public School in Medellin, Colombia. Oral examinations in order to determine the DMF-T Index (Decay, Missing and Filling Teeth) were carried out. Isolates were identified by the Streptoccocus sobrinus and Streptococcus mutans PCR, API 20STREP and 16S rRNA sequence analysis. Genotypes c, e, f and k were detected by PCR. Results: Prevalence of S. mutanswas 14.9%. Of the 47 saliva samples, 57.4% (27) corresponded to children with dental caries, and 8.5% (4) were positive for S. mutans genotype c, 2.1% (1 each) genotype f genotype k, and genotype cand k, respectively. Conclusion: Prevalence of S. mutanswas lower than in previous studies of Colombian children with similar demographic characteristics. Streptoccocusmutans'genotype c, fand kwere found in children with caries but not in the group without caries. This is the first report of S. mutans genotype kin Colombia; this genotype requires further study to clarify its relation with dental caries and cardiovascular disease in Colombia.

Resumen Introducción y objetivo: La caries dental es una de las enfermedades infecciosas de la cavidad oral más comunes en el mundo. El objetivo de este estudio fue determinar la prevalencia de Streptococcus mutansy sus genotipos en muestras de saliva de niños de 6 y 7 años, con y sin caries dental. Materiales y métodos: Cuarenta y siete (47) muestras de saliva fueron obtenidas de niños de 6-7 años, seleccionados aleatoriamente de una escuela pública en Medellín, Colombia. Se realizaron evaluaciones orales para determinar el índice COP-D (número de dientes permanentes cariados, obturados y perdidos). Los aislamientos fueron identificados mediante PCR para diferenciación de S. sobrinusy S. mutans, API-20STREP y análisis de ARNr 16S. Se determinaron mediante PCR los genotipos c e, fy ken las cepas identificadas como S. mutans. Resultados: La prevalencia de S. mutansfue 14,9%. De las 47 muestras de saliva, 57,4% (27) correspondieron a niños con caries dental, y 8,5 % (4), fueron positivas para S. mutans genotipo c, 2,1 % (1 cada una) genotipo f genotipo ky genotipo cy k, respectivamente. Conclusión: La prevalencia de S. mutansfue menor que la reportada en estudios previos de niños colombianos con características demográficas similares. Se encontró presencia de genotipos c, fy kde S. mutansen niños con caries dental, pero no en el grupo de niños sin caries dental. Este es el primer estudio en reportar la presencia del genotipo ken Colombia. Es necesario realizar más investigaciones en nuestro país para aclarar la relación de S. mutans genotipo k con caries dental y enfermedad cardiovascular.

Enfermedad de Chagas agudo: transmisión oral de Trypanosoma cruzi como una vía de transmisión re-emergente

La forma clínica más común de la enfermedad de Chagas en Colombia es la cardiomiopatía chagásica crónica. Sin embargo, recientemente se han presentado nueve brotes de Chagas agudo (EChA) de probable transmisión oral en áreas de baja endemia con escasa presencia de vectores domiciliados. Estos brotes han presentado altas tasas de morbilidad y mortalidad. La transmisión oral de Trypanosoma cruzi ocurre por ingestión de alimentos contaminados con heces de insectos vectores o secreciones de reservorios silvestres contaminadas. Se considera un brote de transmisión oral cuando se detecta más de un caso agudo de enfermedad febril, sin vía de inoculación aparente, asociado con ingesta de alimentos sospechosos. El diagnóstico se hace por la detección del parásito en sangre u otros fluidos biológicos, en los primeros días de presentación del síndrome febril.

The most common clinical form of Chagas disease in Colombia is the chronic Chagas cardiomyopathy. However, recently nine outbreaks of acute Chagas disease by probable oral transmission have been described in low endemic areas with scarce presence of domiciliated vectors. These outbreaks have had high rates of morbidity and mortality. The oral transmission of Trypanosoma cruzi occurs by the ingestion of contaminated food with feces of vectors or secretions of wild reservoirs. An oral transmission outbreak is considered when more than one individual shows an acute febrile illness without an inoculation route, and associated with suspected food intake. The diagnosis is made by detection of parasite in blood or other biological fluids, in the early days of presentation of febrile syndrome.

Comparison of starting ovarian stimulation on day 2 versus day 15 of the menstrual cycle in the same oocyte donor and pregnancy rates among the corresponding recipients of vitrified oocytes.

OBJECTIVE: To assess the clinical pregnancy rate per transfer in recipients of embryos from donor oocytes obtained after ovarian stimulation initiated on day 2 (D2) or day 15 (D15) of the menstrual cycle with a secondary end point of comparing the response to stimulation. DESIGN: Prospective observational comparative study. SETTING: Private in vitro fertilization (IVF) program. PATIENT(S): Oocyte donors (OD) and recipients. INTERVENTION(S): Donors stimulated within 3 months, starting on day 2 or day 15 after bleeding, with recombinant follicle-stimulating hormone (FSH), gonadotropin-releasing hormone (GnRH) antagonist, and GnRH agonist trigger, and oocytes vitrified and later assigned to recipients, followed by routine IVF procedures one to two embryos transferred. MAIN OUTCOME MEASURE(S): Primary outcome pregnancy rate, and secondary outcome number of mature oocytes retrieved. RESULT(S): Nine D2 and nine D15 cycles were performed in nine donors. There were no differences between D2 and D15 in the number of mature oocytes obtained (14.0±6.96 vs. 16.89±7.52). To date, 20 recipients have received vitrified oocytes (8 recipients received D2 oocytes and 12 recipients received D15 oocytes). There were no differences between the groups of recipients in fertilization rate (77.3% vs. 76.5%) or number of embryos transferred (1.50±0.53 vs. 1.67±0.65). Twelve clinical pregnancies were obtained. No differences were noted in pregnancy rates (62.5% vs. 58.3%) or implantation rates (41.67% vs. 45%) between recipients of D2 oocytes and recipients of D15 oocytes. CONCLUSION(S): Donor oocytes obtained after ovarian stimulation initiated on day 15 of the cycle achieve good pregnancy rates. This information is useful for patients with cancer undergoing fertility preservation. CLINICAL TRIAL REGISTRATION NUMBER: NCT 01645241.