Virus entéricos distintos de rotavirus y norovirus en menores de 5 años con gastroenteritis en Argentina, 2010-2021. Estudio descriptivo / Enteric viruses other than rotavirus and norovirus in children under 5 years of age with gastroenteritis in Argentina, 2010­2021. A descriptive study

Introducción. Los datos de frecuencia de los adenovirus entéricos, sapovirus y astrovirus en casos de gastroenteritis aguda esporádica en Argentina son escasos. Métodos. Diseño descriptivo sobre una selección de muestras de heces de menores de 5 años con diarrea remitidas durante el período 2010-2021, con resultado previo negativo para rotavirus y norovirus. Se estudió la presencia de adenovirus entéricos, sapovirus y astrovirus por métodos moleculares, con posterior genotipificación de las muestras positivas. Resultados. De 574 muestras seleccionadas, en 226 (39,4 %) se identificó al menos uno de los virus estudiados. En particular, se detectaron adenovirus, sapovirus y astrovirus en el 30,7 %, el 5,6 % y el 3,1 %, respectivamente. El adenovirus 41, los sapovirus GI.1 y GI.2, y el astrovirus 1 fueron los más frecuentemente detectados. Se identificaron dos muestras con astrovirus no clásicos. Conclusiones. A pesar de ser menos frecuentes, estos enteropatógenos son responsables de un número considerable de episodios de diarrea esporádica. Por lo tanto, su estudio y vigilancia contribuye significativamente a reducir la brecha de casos no diagnosticados.

Introduction. Data on the frequency of enteric adenoviruses, sapoviruses, and astroviruses in cases of sporadic acute gastroenteritis in Argentina are scarce. Methods. Descriptive design of a selection of fecal samples of children with diarrhea younger than 5 years referred between 2010 and 2021, with a previous negative result for rotavirus and norovirus. The presence of enteric adenovirus, sapovirus, and astrovirus was tested by molecular methods, with subsequent genotyping of positive samples. Results. At least 1 of the tested viruses was detected in 226 (39.4%) of the 574 selected samples. Specifically, adenovirus, sapovirus, and astrovirus were detected in 30.7%, 5.6%, and 3.1% of the samples, respectively. The most frequent viruses detected were adenovirus 41, sapoviruses GI.1 and GI.2, and astrovirus 1. Non-classic astroviruses were detected in 2 samples. Conclusions. Despite being less frequent, these enteropathogens are responsible for a large number of sporadic diarrhea events. Therefore, their study and surveillance contribute significantly to reduce the gap of undiagnosed cases.

Differences in Muscle Strength Performance According to the Genotypes of the rs4646994 Polymorphism of the ACE Gene in a Sedentary Population / Diferencias en el Rendimiento de la Fuerza Muscular Según los Genotipos del Polimorfismo rs4646994 del Gen ACE en una Población Sedentaria

SUMMARY: The angiotensin converting enzyme gene (ACE) has been associated with endurance and strength performance through its I/D polymorphism. Nevertheless, contradictory results exist between different populations. In this context, the purpose of this research was to determine the influence of the I/D polymorphism of the ACE gene on muscle strength in a sedentary Chilean sample. In this study 102 healthy male students (21.3 ± 2.2 years) completed the assessment. I/D genotyping, cardiovascular, anthropometric, grip strength and knee extensor peak strength were evaluated. The ACE polymorphism frequency was: II, 33.3 %; ID, 46.1 %; DD, 20.6 %. The results showed significant differences and large effect size in maximum (p = 0.004; d = 0.85) and relative handgrip strength (p = 0.004; d = 0.9) between genotype II vs DD. No difference was found for maximal or relative knee extensor strength between groups (p = 0.74), showing a low effect size (d = 0.20). In conclusion, this study provides insights into the role of the ACE gene in muscle strength and highlights the importance of investigating genetic variants in sedentary populations to better understand strength performance.

El gen de la enzima convertidora de angiotensina (ACE) se ha asociado con el rendimiento de resistencia y fuerza a través de su polimorfismo I/D. Sin embargo, existen resultados contradictorios entre diferentes poblaciones. En este contexto, el propósito de esta investigación fue determinar la influencia del polimorfismo I/D del gen ACE sobre la fuerza muscular en una muestra chilena sedentaria. En este estudio, fueron evaluados 102 estudiantes varones sanos (21,3 ± 2,2 años). Se realizaron aplicaron las siguientes evaluaciones: genotipado del polimorfismo I/D, cardiovascular, antropométrica, fuerza de prensión y fuerza máxima de extensión de rodilla. La frecuencia del polimorfismo I/D de ACE fue: II, 33,3 %; DNI, 46,1 %; DD, 20,6 %. Los resultados mostraron diferencias significativas y un gran tamaño del efecto en la fuerza máxima (p = 0,004; d = 0,85) y relativa de prensión manual (p = 0,004; d = 0,9) entre el genotipo II y el DD. No se encontraron diferencias en la fuerza máxima o relativa de los extensores de rodilla entre los grupos (p = 0,74), lo que muestra un tamaño de efecto bajo (d = 0,20). En conclusión, este estudio proporciona información sobre el papel del gen ACE en la fuerza muscular y destaca la importancia de investigar variantes genéticas en poblaciones sedentarias para comprender mejor el rendimiento de la fuerza.

Identificación del alelo HLA B*57: 01 en una población militar, de Lima-Perú / Identification of the allele HLA B*57: 01 in a military population, from Lima-Peru

El alelo HLA B*57:01 es un marcador genético asociado con la hipersensibilidad al fármaco anti-retroviral abacavir (ABC) y su frecuencia en la población peruana todavía es desconocida. El objetivo fue identificar el alelo HLA B*57:01 en una población militar de Lima, Perú. Se reclutaron 43 personas viviendo con VIH (PVV) quienes aceptaron participar a través de un consentimiento informado. La detección del alelo HLA B*57:01 se realizó mediante RPC en tiempo real (RT-PCR). Asimismo, se determinó la carga viral (CV), el recuento de linfocitos CD4 y la genotipificación del VIH. Se identificaron dos casos positivos al alelo HLA B*57:01 (4,7%). Además, uno de ellos presentó múltiples mutaciones de resistencia a los anti-retrovirales (ARV), incluyendo ABC. Se demostró por primera vez en el Perú la presencia del alelo HLA B*57:01.

The HLA B*57:01 allele is a genetic marker associated with hypersensitivity to the antiretroviral Abacavir (ABC) and its frequency in the Peruvian population is still unknown. The objective was to identify the HLA B*57:01 allele in a military population from Lima, Peru. Forty three people living with HIV (PLWH) were recruited, who agreed to participate through informed consent. Detection of the HLA B*57:01 allele was performed by real-time PCR (RT-PCR). Likewise, viral load (VL), CD4 lymphocyte count and HIV genotyping were determined. Two cases positive for the HLA B*57:01 allele (4.7%) were identified. In addition, one of them had multiple resistance mutations to antiretrovirals (ARVs), including ABC. The presence of the HLA B*57:01 allele was demonstrated for the first time in Peru.

Distribución de genotipos de virus papiloma humano de alto riesgo en mujeres y hombres atendidos en una red asistencial privada en la Región Metropolitana, Chile / Distribution of high-risk human papillomavirus genotypes in women and men attended in a private healthcare network in the Metropolitan Region, Chile

Introducción: La infección persistente por genotipos de virus papiloma humano de alto riesgo (VPH-AR) es la principal causa del cáncer cérvico-uterino en todo el mundo. Los genotipos 16 y 18 están asociados a la progresión hacia el cáncer de cuello uterino; sin embargo, otros genotipos también presentan alto riesgo oncogénico. Existe escasa evidencia respecto a la distribución de genotipos VPH-AR en la población nacional, siendo un tema que debiese ser abordado en el contexto de un creciente aumento de la inmigración e implementación del programa de inmunización en Chile desde 2015. Objetivo: Dar a conocer la distribución de genotipos de VPH-AR detectados en pacientes de ambos sexos, atendidos en la red de atención privada de Clínica Dávila de Santiago, entre los años 2014 y 2021. Metodología: Se estudiaron muestras genitales y anales provenientes de 3.642 pacientes, incluyendo ambos sexos. La genotipificación fue realizada mediante reacción de la polimerasa en cadena (RPC) en tiempo real (HPV AnyplexTM II HPV28 detection, Seegene, Korea. Resultados: La distribución global de genotipos en mujeres (porcentaje) fue: 16 (14,34%) - 31 (6,20%) - 39 (5,94%) - 58 (5,94%) - 51 (5,68%) - 53 (5,64%) - 52 (5,30%) - 56 (5,27%) - 68 (5,19%) - 66 (4,97% - 18 (3,36%) - 59 (3,29%) - 73 (2,80%) - 35 (2,54%) - 45 (2,13%) - 33 (1,53%) - 82 (1,38%) - 26 (0,49%) y 69 (0,41%). En hombres fue: 16 (8,52%) - 58 (4,39%) - 51 (8,44%) - 26 (0,42%) - 18 (3,21%) - 52 (4,47%) - 39 (5,40%) - 53 (4,56%) - 33 (1,69%) - 35 (2,03%), 73 (2,19%) - 69 (0,59%) - 45 (2,11%) - 59 (4,22%) - 68 (3,04%) - 66 (5,06%) - 31 (4,64%) - 56 (4,81%) y 82 (1,10%). Conclusiones: La distribución de los genotipos de VPH fue concordante con estudios previos nacionales. Se observó una tendencia a la reducción del genotipo 16 en el tiempo, lo cual podría relacionarse a la vacunación, implementada en los últimos años en Chile. Destaca que otros genotipos de VPH-AR tuvieron una alta frecuencia en la población estudiada por lo que sería recomendable evaluar la pesquisa ampliada de genotipos de VPH-AR para valorar el riesgo oncogénico, con fines diagnósticos y terapéuticos.

Background: Persistent infection by high-risk human papillomavirus (HR-HPV) genotypes is the main cause of cervical cancer worldwide. Genotypes 16 and 18 are associated with progression to cervical cancer, however other genotypes also present high oncogenic risk. There is little evidence regarding the distribution of HR-HPV genotypes in the national population, being an issue that should be addressed in the context of a growing increase in immigration and implementation of the immunization program in Chile since 2015. Aim: To show the distribution of HR-HPV genotypes detected in women and men, attended at the private care network of Clinica Davila, Santiago City, between 2014 and 2021. Methods: Genital and anal samples from 3,642 patients were studied, including both sexes. Genotyping was performed by real-time polymerase chain reaction (PCR) (HPV AnyplexTM II HPV28 detection, Seegene, Korea). Results: The global distribution of genotypes in women (percentage) was: 16 (14.34%) - 31 (6.20%) - 39 (5.94%) - 58 (5.94%) - 51 (5.68%) - 53 (5.64%) - 52 (5.30%) - 56 (5.27%) - 68 (5.19%) - 66 (4.97%) - 18 (3.36%) - 59 (3.29%) - 73 (2.80%) - 35 (2.54%) - 45 (2.13%) - 33 (1.53%) - 82 (1.38%) - 26 (0.49%) and 69 (0.41%). In men was: 16 (8.52%) - 58 (4.39%) - 51 (8.44%) - 26 (0.42%) - 18 (3.21%) - 52 (4.47%) - 39 (5.40%) - 53 (4.56%), 33 (1.69%) - 35 (2.03%) - 73 (2.19%) - 69 (0.59%) - 45 (2.11%) - 59 (4.22%) - 68 (3.04%) - 66 (5.06%) - 31 (4.64%) - 56 (4.81%) and 82 (1.10%). Conclusions: The distribution of HPV genotypes was consistent with previous national studies. A tendency to reduce genotype 16 over the years was observed, which could be related to the vaccination, implemented in recent years in Chile. It is remarkable that other HR-HPV genotypes had a high frequency in the population studied, so it would be advisable to evaluate an expanded screening for HR-HPV genotypes to assess the oncogenic risk, for diagnostic and therapeutic purposes.

Detección e integración del virus del papiloma humano de alto riesgo en lesiones pre-neoplásicas en mujeres del sur de Chile: un estudio transversal / High-risk human papillomavirus detection and integration in preneoplastic lesions among women in Southern Chile: a cross-sectional study

INTRODUCCIÓN: El virus del papiloma humano de alto riesgo (VPH-AR) es responsable del cáncer de cuello uterino y sus lesiones preneoplásicas. Los genotipos VPH16 y VPH18 son los más frecuentes en este cáncer. La integración del VPH-AR en el genoma de la célula hospedera es crucial en la carcinogénesis cervical, pero la etapa en que ocurre en la población chilena es incierta. OBJETIVO: Evaluar la integración de VPH16 y VPH18 en lesiones pre-neoplásicas de cuello uterino. MÉTODOS: Se analizaron 108 muestras de raspados cervicales. El VPH se genotipificó mediante reacción de polimerasa en cadena (RPC) e hibridación no radiactiva. La integración de VPH16 y VPH18 se determinó por presencia del gen E2 mediante RPC. RESULTADOS: VPH16 y VPH18 se detectaron en 36,1% y 12,0% de las muestras, respectivamente. El VPH16 se integró en 23,1% de los casos de VPH16, mientras que VPH18 se integró en 100% de las muestras positivas para este genotipo. CONCLUSIONES: La integración VPH-AR es un evento temprano en la carcinogénesis cervical que ocurre en casi la mitad de las lesiones pre-neoplásicas y es más frecuente en VPH18 que en VPH16. La evaluación de la integración VPH-AR puede ser una herramienta útil para detectar el virus en la población chilena.

BACKGROUND: High-risk Human Papillomaviruses (HR-HPVs) are the etiological agents of cervical cancer and its preneoplastic lesions. HPV16 and 18 are the most frequent HR-HPV genotypes detected in cervical cancer. HR-HPV genome integration into the host cell is an important event in the carcinogenic process. However, it remains uncertain which stage of cervical carcinogenesis HPV16 and 18 integration occurs in the Chilean population. AIM: The goal of this study was to evaluate HPV16 and HPV18 integration in preneoplastic lesions of the cervix. METHODS: DNA was extracted from 108 cervical scrape samples with preneoplastic lesions. HPV was genotyped using PCR and non-radioactive hybridization. The integration status of HPV16 and HPV 18 was determined by evaluating the E2 gene presence through PCR. RESULTS: HPV16 and HPV18 tested positive in 36.1% and 12.0% of samples, respectively. HPV16 was found integrated in 23.1% of HPV 16 cases, while HPV 18 in 100% of samples positive for this viral genotype. CONCLUSIONS: HR-HPV integration is an early event in cervical carcinogenesis, occurring in nearly half of preneoplastic lesions and being more frequent in HPV18 than in HPV16. The evaluation of HR-HPV integration can be utilized as a complementary tool for detecting HPV in the Chilean population.

Correlation of early neurodevelopmental features of children with SYNGAP1 variants and their genotypes / 中华医学遗传学杂志

OBJECTIVE@#To explore the early neurodevelopmental features of young children with SYNGAP1 variants and their genotype-phenotype correlation.@*METHODS@#Young children with neurodevelopmental disorders (NDDs) (< 5 years old) who were referred to the Children's Hospital Affiliated to the Capital Institute of Pediatrics between January 2019 and July 2022 were selected as the study subjects. All children had undergone whole-exome sequencing, comprehensive pediatric neuropsychological assessment, familial segregation analysis, and pathogenicity classification. Meanwhile, young Chinese NDD children (< 5 years old) with pathogenic/likely pathogenic SYNGAP1 variants were retrieved from the literature, with information including detailed clinical and genetic testing, neurodevelopmental quotient (DQ) of the Children Neuropsychological and Behavior Scale-Revision 2016 (CNBS-R2016). Children who did not have a detailed DQ but had their developmental status assessed by a medical professional were also included. The correlation between neurodevelopmental severity, comorbidity and SYNGAP1 variants were summarized.@*RESULTS@#Four young NDD children carrying SYNGAP1 variants were recruited (1 male and 3 females, with a mean age of 34.0 ± 18.2 months), among whom one harboring a novel variant (c.437C>G, p.S146*). Combined with 19 similar cases retrieved from the literature, 23 Chinese NDD young children were included in our study (8 males and 10 females, 5 with unknown sex, with a mean age of 37.1 ± 14.2 months). A loss of function (LOF) variant was found in 19 (82.6%) children. All of the children had presented global developmental delay (GDD) before the age of two. In addition, 16 (69.6%) had seizure/epilepsy at the age of 27.0 ± 12.1 months, among whom 15 had occurred independent of the global developmental delay. Myoclonic and absence were common types of seizures. Compared with those with variants of exons 8 to 15, the severity of developmental delay was milder among children with variants in exons 1 to 5.@*CONCLUSION@#The early neurodevelopment features of the SYNGAP1 variants for young children (< 5 years old) have included global developmental delay and seizure/epilepsy. All of the children may present GDD before the age of two. The severity of developmental delay may be related to the type and location of the SYNGAP1 variants.

Establishment of a genotyping method for the junior blood group and identification of a rare blood type with partial DVI.3 and Jr(a-) / 中华医学遗传学杂志

OBJECTIVE@#To develop a genotyping method for the Junior blood type and report on a rare blood type with Jr(a-).@*METHODS@#Healthy O-type RhD+ volunteer donors of the Shenzhen Blood Center from January to May 2021 (n = 1 568) and a pedigree with difficult cross-matching (n = 3) were selected as the study subjects. Serological methods were used for proband's blood type identification, unexpected antibody identification, and antibody titer determination. Polymerase chain reaction-sequence specific primer (PCR-SSP) method was used for typing the proband's RhD gene. ABCG2 gene coding region sequencing and a PCR-SSP genotyping method were established for determining the genotypes of the proband and his family members and screening of Jra antigen-negative rare blood type among the 1 568 blood donors.@*RESULTS@#The proband's ABO and RhD blood types were respectively determined as B and partial D (RHDDVI.3/RHD01N.01), Junior blood type Jra antigen was negative, and plasma had contained anti-D and anti-Jra. Sequencing of the ABCG2 gene revealed that the proband's genotype was ABGG201N.01/ABGG201N.01 [homozygous c.376C>T (p.Gln126X) variants], which is the most common Jr(a-) blood type allele in the Asian population. Screening of the voluntary blood donors has detected no Jr(a-) rare blood type. Statistical analysis of the heterozygotes suggested that the allelic frequency for ABCG2*01N.01 (c.376T) was 0.45%, and the frequency of Jr(a-) rare blood type with this molecular background was about 0.2‰.@*CONCLUSION@#A very rare case of partial DVI.3 type and Jr(a-) rare blood type has been identified. And a method for identifying the Junior blood type through sequencing the coding regions of the ABCG2 gene and PCR-SSP has been established.

Age and sex-related Chromogranin A Gene Polymorphisms and its association with metabolic syndrome components / Journal of the ASEAN Federation of Endocrine Societies

Introduction@#The purpose of this study was to determine the possible differences in genetic polymorphisms and serum levels of chromogranin A (CgA), according to age and sex, in subjects with and without metabolic syndrome (MetS).@*Methodology@#The genotyping and serum level of CgA and biochemical parameters were measured by the T-ARMS-PCR and PCR-RFLP and ELISA and spectrophotometer methods, respectively.@*Results@#A comparison of males with and without MetS showed significantly lower high-density lipoprotein-cholesterol (HDL-C) levels than those of females. At ages 30-70 years, both sexes showed significant differences in triglycerides (TG), fasting blood sugar (FBS), CgA levels and waist circumference (WC) when compared to the two groups. Both sexes with MetS indicated significant differences in systolic blood pressure (SBP) at ages 40-70 years, while at ages 40-59 years, there was a significant difference in HDL-C level in males. There was a significant correlation between serum levels of FBS, TG, SBP and WC (in both sexes), and CgA in subjects with MetS. Significant correlation was found between HDL-C level and diastolic blood pressure (DBP), and CgA level in males and females, respectively. CgA genotype frequency (T-415C and C+87T polymorphisms) showed no significant differences between males and females with and without MetS, while there was only a significant difference in frequency of the genotypes T-415C when compared to males with and without MetS.@*Conclusion@#The CgA appears to be strongly associated with MetS components in both sexes. Variation in CgA gene expression may affect the T–415C polymorphism in males. This may mean that the structure of CgA genetics differs in different ethnic groups. Differences in the serum level and expression of CgA gene may show valuable study results that it may be expected a relationship between these variables and the MetS.

A genetic variant in the immune-related gene ERAP1 affects colorectal cancer prognosis / 中华医学杂志(英文版)

BACKGROUND@#Findings on the association of genetic factors and colorectal cancer (CRC) survival are limited and inconsistent, and revealing the mechanism underlying their prognostic roles is of great importance. This study aimed to explore the relationship between functional genetic variations and the prognosis of CRC and further reveal the possible mechanism.@*METHODS@#We first systematically performed expression quantitative trait locus (eQTL) analysis using The Cancer Genome Atlas (TCGA) dataset. Then, the Kaplan-Meier analysis was used to filter out the survival-related eQTL target genes of CRC patients in two public datasets (TCGA and GSE39582 dataset from the Gene Expression Omnibus database). The seven most potentially functional eQTL single nucleotide polymorphisms (SNPs) associated with six survival-related eQTL target genes were genotyped in 907 Chinese CRC patients with clinical prognosis data. The regulatory mechanism of the survival-related SNP was further confirmed by functional experiments.@*RESULTS@#The rs71630754 regulating the expression of endoplasmic reticulum aminopeptidase 1 ( ERAP1 ) was significantly associated with the prognosis of CRC (additive model, hazard ratio [HR]: 1.43, 95% confidence interval [CI]: 1.08-1.88, P = 0.012). The results of dual-luciferase reporter assay and electrophoretic mobility shift assay showed that the A allele of the rs71630754 could increase the binding of transcription factor 3 (TCF3) and subsequently reduce the expression of ERAP1 . The results of bioinformatic analysis showed that lower expression of ERAP1 could affect the tumor immune microenvironment and was significantly associated with severe survival outcomes.@*CONCLUSION@#The rs71630754 could influence the prognosis of CRC patients by regulating the expression of the immune-related gene ERAP1 .@*TRIAL REGISTRATION@#No. NCT00454519 ( https://clinicaltrials.gov/ ).

Analysis of the complete genome characterization of 11 human astrovirus strains in Shandong Province / 中华预防医学杂志

Objective: To study the complete genome characterization of Human Astrovirus (HAstV) in Shandong Province. Methods: Stool samples from acute flaccid paralysis (AFP) surveillance in Shandong Province from 2020 to 2022 were collected, and HAstV nucleic acid was examined by real-time quantitative PCR (qPCR). Next-generation sequencing (NGS) was conducted for the positive samples to obtain complete genome sequences and identify the genotype. Homology comparison and phylogenetic analysis were performed by using BioEdit and Mega software. Results: A total of 667 samples were examined by qPCR, of which 14 were HAstV-positive (2.1%), including HAstV-1 (n=6), MLB1 (n=6), MLB2 (n=1), and VA2 (n=1). The complete genome sequences were obtained from 11 samples. The six HAstV-1 sequences of this study had 98.2% to 99.9% nt similarities with each other and 87.6% to 98.6% with those from other regions. The four MLB1 sequences of this study had 99.1% to 99.9% nt similarities with each other and 92.2% to 99.4% with those from other regions. The VA2 sequence of this study had 96.0% to 96.3% nt similarities with those from other regions. Phylogenetic analysis based on ORF2 region showed that the local HAstV-1 sequences were most closely related to Japanese strains, and had distinct topology with phylogenies based on ORF1a and ORF1b regions. Conclusion: The complete genome sequences of 11 HAstV strains are obtained, and the VA2 complete genome is found.

Analysis of the complete genome characterization of 11 human astrovirus strains in Shandong Province / 中华预防医学杂志

Objective: To study the complete genome characterization of Human Astrovirus (HAstV) in Shandong Province. Methods: Stool samples from acute flaccid paralysis (AFP) surveillance in Shandong Province from 2020 to 2022 were collected, and HAstV nucleic acid was examined by real-time quantitative PCR (qPCR). Next-generation sequencing (NGS) was conducted for the positive samples to obtain complete genome sequences and identify the genotype. Homology comparison and phylogenetic analysis were performed by using BioEdit and Mega software. Results: A total of 667 samples were examined by qPCR, of which 14 were HAstV-positive (2.1%), including HAstV-1 (n=6), MLB1 (n=6), MLB2 (n=1), and VA2 (n=1). The complete genome sequences were obtained from 11 samples. The six HAstV-1 sequences of this study had 98.2% to 99.9% nt similarities with each other and 87.6% to 98.6% with those from other regions. The four MLB1 sequences of this study had 99.1% to 99.9% nt similarities with each other and 92.2% to 99.4% with those from other regions. The VA2 sequence of this study had 96.0% to 96.3% nt similarities with those from other regions. Phylogenetic analysis based on ORF2 region showed that the local HAstV-1 sequences were most closely related to Japanese strains, and had distinct topology with phylogenies based on ORF1a and ORF1b regions. Conclusion: The complete genome sequences of 11 HAstV strains are obtained, and the VA2 complete genome is found.

Characterization of the Bipolaris maydis: symptoms and pathogenicity in popcorn genotypes (Zea mays L. ) / Caracterização de Bipolaris maydis: sintomas e patogenicidade em genótipos de milho-pipoca (Zea mays L. )

Southern corn leaf blight (SCLB) is one of the most important corn leaf diseases. Appropriate management strategies and the use of resistant cultivars allow disease control. Therefore, knowing the aspects related to the pathogen and the response of hosts makes it possible to design efficient strategies for selecting genotypes resistant to this disease. In this sense, the objective was to carry out the Bipolaris maydis isolate characterization, evaluating the pathogenicity in different popcorn lines and the symptoms generated in the host after inoculation. The isolate characterization consisted of the macromorphological evaluation of the colonies and the micromorphological evaluation of the conidia in the PDA medium. An experiment was carried out in a greenhouse to evaluate the pathogenicity of the isolate, using 20 inbred lines of popcorn in a randomized block design with four replicates. Inoculation was carried out by spraying leaves, with a suspension containing 1.0 x 104 conidia.ml-1 of the CF/UENF 501 isolate of B. maydis. An incidence assessment and three assessments of disease symptom severity were performed, with seven days intervals between evaluations. The morphological characterization data of the isolate were analyzed using descriptive statistics, and for disease severity, the linear regression model was applied the first-degree model. The variance analysis was performed for the linear and angular coefficients obtained for each treatment. When a difference was found, the Scott-Knott clustering algorithm at 5% significance was applied. The isolate had gray-green colonies, a cottony appearance, and an irregular shape. The lines L353, L354, and L624 show more resistance at the beginning and throughout the evaluations. The high virulence of the CF/UENF 501 isolate made it possible to differentiate the lines in terms of disease intensity and the pattern of symptoms presented.

Mancha-de-Bipolaris é uma das mais importantes doenças foliares do milho. Estratégias de manejo adequadas e o uso de cultivar resistente permitem o controle da doença, mas para tanto, conhecer os aspectos associados ao patógeno e a resposta do hospedeiro é necessário para traçar estratégias eficientes para seleção de genótipos resistentes a essa doença. Neste sentido, objetivou-se realizar a caracterização do isolado de Bipolaris maydis avaliando a patogenicidade em diferentes linhagens de milho-pipoca e os sintomas gerados no hospedeiro a partir da inoculação. A caracterização do isolado consistiu na avaliação macromorfológica das colônias e micromofológica dos conídios em meio nutritivo BDA. Para avaliação da patogenicidade do isolado foi conduzido um experimento em casa de vegetação utilizando 20 linhagens endogâmicas de milho-pipoca, com delineamento em blocos casualizados, com quatro repetições. A inoculação foi realizada por meio de pulverização em folhas, com uma suspensão contendo 1,0 x 104 conídios.ml-1 do isolado CF/UENF 501 de B. maydis. Foi realizada uma avaliação de incidência e três avaliações de severidade dos sintomas da doença, com o intervalo de sete dias para cada avaliação. Os dados da caracterização morfológica do isolado foram analisados por meio da estatística descritiva e para severidade da doença foi aplicado o modelo de regressão linear de primeiro grau. Realizou-se a análise de variância para o coeficiente linear e angular obtido para cada tratamento e quando constatada diferença aplicou-se o agrupamento de médias de Scott-knott a 5% de significância. O isolado apresentou colônias com coloração cinza esverdeado, aspecto algodonoso e forma irregular. As linhagens L353 e L354 e L624 estão entre as linhagens que apresentaram maior resistência no inicio e ao longo das avaliações. A elevada virulência do isolado CF/UENF 501 possibilitou diferenciar as linhagens quanto a intensidade da doença, bem como o padrão dos sintomas apresentados.

Association of vitamin D receptor gene polymorphisms with type 2 diabetes mellitus in Taif population: a case-control study / Associação de polimorfismos do gene do receptor de vitamina D com diabetes mellitus tipo 2 na população Taif: um estudo de caso-controle

Abstract Several reasons may underlie the dramatic increase in type2 diabetes mellitus. One of these reasons is the genetic basis and variations. Vitamin D receptor polymorphisms are associated with different diseases such as rheumatoid arthritis and diabetes. The aim of this study is to investigate the possible association of two identified mutations ApaI (rs7975232) and TaqI (rs731236). Eighty-nine healthy individuals and Fifty-six Type 2 Diabetic (T2D) patients were investigated using RFLP technique for genotyping and haplotyping as well. The distribution of Apal genotypes was not statistically significant among the control (P=0.65) as well as for diabetic patients (P=0.58). For Taql allele frequencies of T allele was 0.61 where of G allele was 0.39. The frequency distribution of Taql genotypes was not statistically significant among the control (P=0.26) as well as diabetic patients (P=0.17). Relative risk of the allele T of Apa1 gene is 1.28 and the odds ratio of the same allele is 1.53, while both estimates were < 1.0 of the allele G. Similarly, with the Taq1 gene the relative risk and the odds ratio values for the allele T are 1.09 and 1.27 respectively and both estimates of the allele C were 0.86 for the relative risk and 0.79 for the odds ratio. The pairwise linkage disequilibrium between the two SNPs Taq1/apa1 was statistically significant in control group (D = 0.218, D' = 0.925 and P value < 0.001) and similar data in diabetic groups (D = 0.2, D' = 0.875 and P value < 0.001). These data suggest that the T allele of both genes Apa1 and Taq1 is associated with the increased risk of type 2 diabetes. We think that we need a larger number of volunteers to reach a more accurate conclusion.

Resumo Várias razões podem estar subjacentes ao aumento dramático da diabetes mellitus tipo 2. Um desses motivos é a base genética e variações. Os polimorfismos do receptor da vitamina D estão associados a diferentes doenças, como artrite reumatoide e diabetes. O objetivo deste estudo é investigar a possível associação de duas mutações identificadas ApaI (rs7975232) e TaqI (rs731236). Oitenta e nove indivíduos saudáveis ​​e 56 pacientes com diabetes tipo 2 (T2D) foram investigados usando a técnica RFLP para genotipagem e haplotipagem também. A distribuição dos genótipos Apal não foi estatisticamente significativa entre o controle (P = 0,65), bem como para os pacientes diabéticos (P = 0,58). Para as frequências do alelo Taql, o alelo T foi de 0,61, onde o alelo G foi de 0,39. A distribuição de frequência dos genótipos Taql não foi estatisticamente significativa entre o controle (P = 0,26), bem como os pacientes diabéticos (P = 0,17). O risco relativo do alelo T do gene Apa1 é 1,28 e a razão de chances do mesmo alelo é 1,53, enquanto ambas as estimativas foram < 1,0 do alelo G. Da mesma forma, com o gene Taq1, os valores de risco relativo e razão de chances para o alelo T são 1,09 e 1,27, respectivamente, e ambas as estimativas do alelo C foram de 0,86 para o risco relativo e 0,79 para o odds ratio. O desequilíbrio de ligação par a par entre os dois SNPs Taq1 / apa1 foi estatisticamente significativo no grupo de controle (D = 0,218, D' = 0,925 e valor P < 0,001) e dados semelhantes em grupos diabéticos (D = 0,2, D' = 0,875 e valor P < 0,001). Esses dados sugerem que o alelo T de ambos os genes Apa1 e Taq1 está associado ao aumento do risco de diabetes tipo 2. Achamos que precisamos de um número maior de voluntários para chegar a uma conclusão mais precisa.

Increased yield performance of mutation induced Soybean genotypes at varied agro-ecological conditions / Aumento no desempenho de rendimento de genótipos de soja induzidos por mutação em condições agroecológicas variadas

Abstract In soybean breeding program, continuous selection pressure on traits response to yield created a genetic bottleneck for improvements of soybean through hybridization breeding technique. Therefore an initiative was taken to developed high yielding soybean variety applying mutation breeding techniques at Plant Breeding Division, Bangladesh Institute of Nuclear Agriculture (BINA), Bangladesh. Locally available popular cultivar BARI Soybean-5 was used as a parent material and subjected to five different doses of Gamma ray using Co60. In respect to seed yield and yield attributing characters, twelve true breed mutants were selected from M4 generation. High values of heritability and genetic advance with high genotypic coefficient of variance (GCV) for plant height, branch number and pod number were considered as favorable attributes for soybean improvement that ensure expected yield. The mutant SBM-18 obtained from 250Gy provided stable yield performance at diversified environments. It provided maximum seed yield of 3056 kg ha-1 with highest number of pods plant-1 (56). The National Seed Board of Bangladesh (NSB) eventually approved SBM-18 and registered it as a new soybean variety named 'Binasoybean-5' for large-scale planting because of its superior stability in various agro-ecological zones and consistent yield performance.

Resumo No programa de melhoramento da soja, a pressão pela seleção contínua para a resposta das características de rendimento criou um gargalo genético para melhorias da soja por meio da técnica de melhoramento por hibridação. Portanto, foi desenvolvida uma variedade de soja de alto rendimento, aplicando técnicas de reprodução por mutação, na Divisão de Melhoramento de Plantas, no Instituto de Agricultura Nuclear de Bangladesh (BINA), em Bangladesh. A cultivar popular BARI Soybean-5, disponível localmente, foi usada como material original e submetida a cinco doses diferentes de raios gama usando Co60. Em relação ao rendimento de sementes e às características de atribuição de rendimento, 12 mutantes genuínos foram selecionados a partir da geração M4. Altos valores de herdabilidade e avanço genético com alto coeficiente de variância genotípico (GCV) para altura da planta, número de ramos e número de vagens foram considerados atributos favoráveis ​​ao melhoramento da soja, garantindo, assim, a produtividade esperada. O mutante SBM-18, obtido a partir de 250Gy, proporcionou desempenho de rendimento estável em ambientes diversificados e produtividade máxima de sementes de 3.056 kg ha-1 com o maior número de vagens planta-1 (56). O Conselho Nacional de Sementes de Bangladesh (NSB) finalmente aprovou o SBM-18 e o registrou como uma nova variedade de soja, chamada 'Binasoybean-5', para plantio em larga escala por causa de sua estabilidade superior em várias zonas agroecológicas e desempenho de rendimento consistente.

Early and late-onset preeclampsia: effects of DDAH2 polymorphisms on ADMA levels and association with DDAH2 haplotypes

Abstract Objective: To examine whether the DDAH2 promoter polymorphisms -1415G/A (rs2272592), -1151A/C (rs805304) and -449G/C (rs805305), and their haplotypes, are associated with PE compared with normotensive pregnant women, and whether they affect ADMA levels in these groups. Methods: A total of 208 pregnant women were included in the study and classified as early-onset (N=57) or late-onset PE (N =49), and as normotensive pregnant women (N = 102). Results: Pregnant with early-onset PE carrying the GC and GG genotypes for the DDAH2 -449G/C polymorphism had increased ADMA levels (P=0.01). No association of DDAH2 polymorphisms with PE in single-locus analysis was found. However, the G-C-G haplotype was associated with the risk for late-onset PE. Conclusion: It is suggested that DDAH2 polymorphisms could affect ADMA levels in PE, and that DDAH2 haplotypes may affect the risk for PE.

Identificación de subtipos de blastocystis sp asociados a fuentes de transmisión en una zona rural del departamento del Quindío / Identification of blastocystis sp subtypes associated to transmission sources in a rural area of the department of Quindío

Introducción. Blastocystis sp es un protozoo parásito que se encuentra en el tracto intestinal del hombre y algunos animales, se estima que infecta a más de 1.000 millones de personas en el mundo. El presente trabajo tuvo como Objetivo determinar los genotipos de Blastocystis sp asociados a diferentes fuentes de transmisión en zona rural del departamento del Quindío. Materiales y Métodos. Se obtuvieron 42 muestras coprológicas de niños entre 0 y 14 años, 17 de heces de animales, 17 de alimentos, 28 de superficies inertes ,15 de suelo, 18 de agua de red domiciliaria y 3 de fuente hídrica. Se realizó extracción de ADN y amplificación por PCR para Blastocystis sp usando como blanco el gen SSADNr. Las secuencias fueron alineadas con ClustalW y se realizaron árboles filogenéticos el programa (MEGA11). Resultados. De las 140 muestras recolectadas entre coprológicos de población infantil y matrices ambientales, se encontró una prevalencia de Blastocystis sp del 23,5 % en alimentos, 22,2% en red domiciliaria y del 4,75 % en la población infantil, no hubo evidencia estadística que implicara una asociación entre la presencia de este protozoo y las variables sociodemográficas. Se encontró el subtipo 2 asociado a población infantil y el subtipo 3 asociado a matrices ambientales (agua y alimentos) y población infantil. Conclusiones: Se reporta la presencia de Blastocystis sp en tomate y zanahoria, en la red domiciliaria y población infantil en una zona rural del departamento del Quindío donde los subtipos asociados fueron el subtipo 2 y 3.

Introduction. Blastocystis sp is a parasitic protozoan found in the intestinal tract of man and some animals, and it is estimated that it infects more than 1,000 million people in the world. In the national parasitism survey, it was reported with a prevalence of 52% in the northern Andean region. The aim of this study was to determine the genotypes of Blastocystis sp associated with different sources of transmission in rural areas of the department of Quindío. Materials and Methods. Forty-two coprological samples were obtained from children between 0 and 14 years of age, 17 from animal feces, 17 from food, 28 from inert surfaces, 15 from soil, 18 from household water and 3 from water sources. DNA extraction and PCR amplification were performed for Blastocystis sp using the SSADNr gene as target. The sequences were aligned with ClustalW and phylogenetic trees were performed with the program (MEGA11). Results. Of the 140 samples collected between coprological samples of children and environmental matrices, we found a prevalence of Blastocystis sp of 23.5% in food, 22.2% in the home network and 4.75% in the child population, there was no statistical evidence implying an association between the presence of this protozoan and sociodemographic variables. Subtype 2 was found associated with infant population and subtype 3 associated with environmental matrices (water and food) and infant population. Conclusions: We report the presence of Blastocystis sp in tomato and carrot, in the home network and infant population in a rural area of the department of Quindío where the associated subtypes were subtype 2 and 3.

¿Está la virtud en el punto medio? La incertidumbre del CIN2 y el papel del VPH / Is virtue at the midpoint? The uncertainty of CIN2 and the role of HPV

Objetivo: La biopsia guiada por colposcopia (BGC) marca el manejo de la neoplasia intraepitelial cervical. El objetivo de este estudio fue evaluar la concordancia de los resultados entre la BGC y la escisión amplia de la zona de transformación (LLETZ, large loop excision of the transformation zone), y la utilidad del genotipado del virus del papiloma humano (VPH) para seleccionar a las pacientes con riesgo de lesión intraepitelial escamosa de alto grado/neoplasia intraepitelial cervical 3 (HSIL/CIN3). Método: Se compararon los resultados de la BGC y de la LLETZ, siendo esta última el método de referencia. Se evaluó la relación del genotipo del VPH con el diagnóstico final de HSIL/CIN3. Resultados: La precisión de la biopsia comparada con LLETZ fue del 61,4%. La tasa de concordancia fue del 64,4% para CIN1, del 31,4% para CIN2 y del 77,4% para CIN3. La tasa global de sobrediagnóstico fue del 18,68% y la de subdiagnóstico del 19,89%. En mujeres menores de 30 años, la concordancia fue del 62,79% (CIN1 65%, CIN2 39,58% y CIN3 73,08%), la tasa de sobrediagnóstico del 22,67% y la tasa de subdiagnóstico del 15,11%. La infección por VPH16 tuvo una odds ratio de 3,86 para el diagnóstico final de HSIL/CIN3+. Conclusiones: El diagnóstico de CIN2 por BGC parece insuficiente para seleccionar a las pacientes para tratamiento escisional, principalmente en mujeres jóvenes. El hallazgo de VPH16 es un factor de riesgo de HSIL/CIN3+ independientemente del resultado de la biopsia.

Objective: Colposcopy-guided biopsy (CGB) is a basic tool for the management of cervical intraepithelial neoplasia. The aim of this study is to evaluate the concordance of results between CGB and large loop excision of the transformation zone (LLETZ), and the usefulness of human papillomavirus (HPV) genotyping to select patients at risk of H-SIL/CIN3. Method: The results of colposcopy-guided biopsy and LLETZ were compared, with LLETZ being the gold standard. The relationship of HPV genotype to the final diagnosis of CIN3 was assessed. Results: The accuracy of CGB compared to LLETZ was 61.4%. The concordance rate was 64.4% for CIN1, 31.4% for CIN2 and 77.4% for CIN3. The overall overdiagnosis rate was 18.68% and underdiagnosis rate was 19.89%. In women under 30 years of age the concordance rate was 62.79% (CIN1 65%, CIN2 39.58% and CIN3 73.08%), and the rate of overdiagnosis and underdiagnosis was 22.67% and 15.11%, respectively. HPV16 infection had an odds ratio of 3.86 for the final diagnosis of CIN3+ and the result was significant regardless of the biopsy result. Conclusions: The CGB result as CIN2 is inaccurate and seems insufficient to select patients for excisional treatment, mainly in young women. HPV16 infection is a risk factor for CIN3+ regardless of the colposcopy-guided biopsy result.

Efecto del sedentarismo sobre la interacción entre el gen FTO y niveles de adiposidad en adultos chilenos - Resultados del Estudio GENADIO / Effect of Sedentary behaviors on the Interaction Between the FTO Gene and Adiposity Levels in Chilean Adults - Results from the GENADIO Study

ANTECEDENTES: Tanto el gen FTO (Fat-mass and obesity-associated-gene) y el tiempo sedente se asocian a obesidad, sin embargo, se desconoce si el tiempo sedente puede modificar la predisposición genética a la obesidad. Por ende, el objetivo de este estudio fue investigar si la asociación entre el polimorfismo rs9939609 del gen FTO y marcadores de adiposidad podrían ser modificados por el tiempo sedente. MÉTODOS: Este estudio de corte transversal incluye a 409 participantes del estudio GENADIO. Los marcadores de adiposidad estudiados fueron peso corporal, índice de masa corporal (IMC), perímetro de cintura (PC) y porcentaje masa grasa. El tiempo sedente se determinó mediante acelerometría de movimiento. La interacción entre el gen FTO (rs9939609) y el tiempo sedente sobre los marcadores de adiposidad se determinó mediante análisis de regresión múltiple. RESULTADOS: Tanto la variante de riesgo del gen FTO como el tiempo sedente se asociaron a mayor peso corporal, IMC, PC y masa grasa. Sin embargo, la asociación entre tiempo sedente y marcadores de adiposidad fue mayor en personas portadoras del alelo de riesgo del gen FTO. Por cada 1 hora de incremento en tiempo sedente, el peso corporal incrementa en 1,36 kg ([95% IC: 0,27; 2,46], p = 0,015) y 2,95 kg ([95% IC: 1,24; 4,65], p = 0,001) en personas con la variante protectora (TT) versus aquellos con la variante de riesgo (AA), respectivamente. Resultados similares se encontraron para (PC). CONCLUSIÓN: La asociación entre la variante de riesgo de FTO y mayor nivel de adiposidad es más acentuada en individuos que presentan mayores niveles de sedentarismo.

BACKGROUND: The Fat-mass and obesity-associated-gene (FTO gene) and sedentary behavior time are associated with obesity. However, whether sedentary behavior time can modify the genetic predisposition to obesity in the Chilean population is unknown. Therefore, this study investigated the association between sedentary behavior, adiposity markers, and the FTO gene. METHODS: This cross-sectional study included 409 participants from the Genes, Environment, Diabetes, and Obesity (GENADIO) study. Adiposity markers studied included body weight, body mass index (BMI), waist circumference (WC), and fat mass. Sedentary behaviors were measured using accelerometers. Using multiple regression, we evaluated the interaction between sedentary behaviors and the FTO gene (rs9939609) on adiposity markers. RESULTS: Sedentary behaviors and the FTO genotype were positively associated with higher body weight, BMI, WC, and fat mass. However, the association between time of sedentary behavior and adiposity markers was higher in carriers of the risk variant for the FTO gene. For each hour of increment in sedentary behaviors, body weight increases by 1.36 kg ([95% CI: 0.27; 2.46], p = 0.015) and 2.95 kg ([95%CI: 1.24; 4.65], p = 0.001) in non-risk carriers (TT) versus risk carriers (AA), respectively. We observed similar results for WC, BMI, and body fat, but the interaction was significant only for WC. CONCLUSION: The association between sedentary behaviors and adiposity markers, especially body weight and WC, is higher in individuals who carry the risk variant of the FTO gene.

Genotipificación del gen RHD en ADN fetal libre en plasma de embarazadas RhD negativo / Genotyping of the RHD gene in free fetal DNA in plasma of RhD negative pregnant women

Objetivo: Determinar el grupo RhD fetal a través del estudio del gen RHD en ADN fetal que se encuentra libre en plasma de embarazadas RhD negativo. Método: Se analizó la presencia de los genes RHD, SRY y BGLO en ADNfl obtenido de plasma de 51 embarazadas RhD negativo no sensibilizadas, utilizando una qPCR. Los resultados del estudio genético del gen RHD se compararon con el estudio del grupo sanguíneo RhD realizado por método serológico en muestras de sangre de cordón, y los resultados del estudio del gen SRY fueron cotejados con el sexo fetal determinado por ecografía. Se calcularon la sensibilidad, la especificidad, los valores predictivos y la capacidad discriminativa del método estandarizado. Resultados: El gen RHD estaba presente en el 72,5% de las muestras y el gen SRY en el 55,5%, coincidiendo en un 100% con los resultados del grupo RhD detectado en sangre de cordón y con el sexo fetal confirmado por ecografía, respectivamente. Conclusiones: Fue posible deducir el grupo sanguíneo RhD del feto mediante el estudio del ADN fetal que se encuentra libre en el plasma de embarazadas con un método molecular no invasivo desarrollado y validado para este fin. Este test no invasivo puede ser utilizado para tomar la decisión de administrar inmunoglobulina anti-D solo a embarazadas RhD negativo que portan un feto RhD positivo.

Objective: To determine the fetal RhD group through the study of the RHD gene in fetal DNA found free in plasma of RhD negative pregnant women. Method: The presence of the RHD, SRY and BGLO genes in fetal DNA obtained from plasma of 51 non-sensitized RhD negative pregnant women was analyzed using qPCR. The results of the genetic study of the RHD gene were compared with the RhD blood group study performed by serological method in cord blood samples, and the results of the SRY gene study were compared with the fetal sex determined by ultrasound. Sensitivity, specificity, predictive values and discriminative capacity of the standardized method were calculated. Results: The RHD gene was present in 72.5% of the samples and the SRY gene in 55.5%, coinciding 100% with the results of the RhD group detected in cord blood, and with the fetal sex confirmed by ultrasound, respectively. Conclusions: It was possible to deduce the RhD blood group of the fetus through the study of fetal DNA found free in the plasma of pregnant women with a non-invasive molecular method developed and validated for this purpose. This non-invasive test can be used to make the decision to administer anti-D immunoglobulin only to RhD-negative pregnant women carrying an RhD-positive fetus.

Identification of antarctic soil bacteria exhibiting antiproliferative activity against a colon cancer cell line / Identificación de bacterias de suelo antártico que presentan actividad antiproliferativa sobre una línea celular de cáncer de colon

SUMMARY: Cancer is the second leading cause of death in the world and colorectal cancer is the only cancer that has shown a sustained increase in mortality in the last decade. In the search for new chemotherapeutic agents against cancer, extremophilic microorganisms have shown to be a potential source to obtain molecules of natural origin and with selective cytotoxic action towards cancer cells. In this work we analyzed the ability of a collection of Antarctic soil bacteria, isolated on Collins Glacier from the rhizosphere of Deschampsia antarctica Desv plant, to secrete molecules capable of inhibiting cell proliferation of a colorectal cancer tumor line. Our results demonstrated that culture supernatants from the Antarctic bacteria K2I17 and MI12 decreased the viability of LoVo cells, a colorectal adenocarcinoma cell line. Phenotypic and genotypic characterization of the Antarctic bacteria showed that they were taxonomically related and nucleotide identity analysis based on the 16S rRNA gene sequence identified the bacterium K2I17 as a species belonging to the genus Bacillus.

El cáncer es la segunda causa de muerte en el mundo y el cáncer colorrectal es el único que presenta un aumento sostenido de la mortalidad en la última década. En la búsqueda de nuevos agentes quimioterapeúticos contra el cáncer, se ha propuesto a los microorganismos extremófilos como una fuente potencial para obtener moléculas de origen natural y con acción citotóxica selectiva hacia las células cancerígenas. En este trabajo analizamos la capacidad de una colección de bacterias de suelo antártico, aisladas en el glaciar Collins desde rizosfera de la planta de Deschampsia antarctica Desv, de secretar moléculas capaces de inhibir la proliferación celular de una línea tumoral de cáncer colorrectal. Nuestros resultados demostraron que los sobrenadantes de cultivo de las bacterias antárticas K2I17 y MI12 disminuyeron la viabilidad de la línea celular de adenocarcinoma colorrectal LoVo, en un ensayo de reducción metabólica de MTT. La caracterización fenotípica y genotípica de las bacterias antárticas, demostró que estaban relacionadas taxonómicamente y el análisis de la identidad nucleotídica en base a la secuencia del gen ARNr 16S identificó a la bacteria K2I17 como una especie perteneciente al género Bacillus.