Blood donor notification rate in a blood bank in Veracruz, Mexico.

Blood banks are primarily responsible for providing safe blood, but they also indirectly act to prevent the spread of infectious diseases by notifying blood donors of positive screening results. The notification process differs between countries and notifications rates are generally low. This study sought to analyze the notification rate of healthy and infection-positive donors who donated blood at CETS-Veracruz. A total of 41790 donors were analyzed, 1585 (3.79%) were positive for one or more of the screened infection markers. Only 4163 (9.96% of the total) were notified about their serology results. Of the positive donors, 157 were contacted by phone call; of them, 91 (57%) returned to the blood bank for their results. The average notification rate for positive donors was only 17.48%. The highest notification rate was for anti-HBc (26.63%), while the lowest was for HBsAg (4.17%). Age significantly influenced the return of donors: Those aged 18-24 and 25-39 years were 4.71 and 1.64 times less likely, respectively, to return for their results compared to the rate for all ages. The advice received in the pre-donation stage about the risks of transfusion-transmitted infections and the relevance of returning for results did not appear to impact donors, since the rate of notification was lower than those reported internationally. These data indicate that CETS-Veracruz should improve donor data registration and communication mechanisms to increase the notification rate, and that donor notification studies should be carried out in other Mexican blood banks to analyze the return rate at the national level.

Occult hepatitis B infections and anti-HBc prevalence at a resource-limited blood bank in Mexico.

OBJECTIVES: To identify blood donors with occult hepatitis B infections (OBIs), determine the prevalence of antibody to hepatitis B core antigen (anti-HBc) positivity and estimate the impact of anti-HBc screening on donor deferral at CETS-Veracruz (Mexico). BACKGROUND: Hepatitis B virus infection is a major concern in transfusion medicine. Mexican regulations only mandate screening for hepatitis B surface antigen (HBsAg), and there are no requirements regarding testing for anti-HBc or use of a nucleic acid test (NAT). There is, therefore, limited information about the prevalence of anti-HBc positivity and occult hepatitis B among blood donors in Mexico. METHODS: This retrospective study examined individuals who donated blood to CETS-Veracruz from June 2014 to June 2017. All donors were serologically examined according to Mexican health regulations, and the prevalence of anti-HBc positivity was determined. A NAT was used to identify individuals with OBIs. RESULTS: We analysed the data of 28 016 blood donors. Over 4 years, the average prevalence of anti-HBc positivity was 1.05%. The risk factors for anti-HBc positivity were low education and age over 50 years. There were nine donors with OBIs. CONCLUSION: The presence of donors with OBIs in CETS-Veracruz and other Mexican blood banks highlights the need to mandate the implementation of anti-HBc screening in Mexico.

Trends in prevalence of HIV and syphilis in a central blood bank of Veracruz, Mexico.

Syphilis and HIV infections continue to threaten the safety of blood banks in countries where altruistic donations are rare. The aim of this study of blood donors to the Centro Estatal de la Transfusion Sanguínea de Veracruz (Mexico) was to determine changes in the prevalence of syphilis and HIV, and to identify factors associated with these infections. A total of 109,054 blood donors were retrospectively analyzed from 2007 to 2014. Serological screening of blood units was performed, and demographic data were collected from clinical records to identify risk factors. The prevalence of Treponema pallidum was 1.4% and that of confirmed HIV was 0.11%. The main risk factors for HIV positivity were age of 18 to 24 years-old, being unmarried, and being an employee or student. The main risk factors for syphilis positivity were being a widow or divorced, being over 35 years-old, having a low level of education, and being a driver, fisherman, or trade worker. There were high prevalences for both infections in southeast Veracruz, where females and males had equal probabilities of each infection. Strengthening of education programs on sexually transmitted diseases for young people may help to prevent new and congenital infections.

Domestic wastewater treatment and power generation in continuous flow air-cathode stacked microbial fuel cell: Effect of series and parallel configuration.

In this study, a continuous flow stack consisting of 40 individual air-cathode MFC units was used to determine the performance of stacked MFC during domestic wastewater treatment operated with unconnected individual MFC and in series and parallel configuration. The voltages obtained from individual MFC units were of 0.08-1.1 V at open circuit voltage, while in series connection, the maximum power and current density were 2500 mW/m2 and 500 mA/m2 (4.9 V), respectively. In parallel connection, the maximum power and current density was 5.8 mW/m2 and 24 mA/m2, respectively. When the cells were not connected to each other MFC unit, the main bacterial species found in the anode biofilms were Bacillus and Lysinibacillus. After switching from unconnected to series and parallel connections, the most abundant species in the stacked MFC were Pseudomonas aeruginosa, followed by different Bacilli classes. This study demonstrated that when the stacked MFC was switched from unconnected to series and parallel connections, the pollutants removal, performance electricity and microbial community changed significantly. Voltages drops were observed in the stacked MFC, which was mainly limited by the cathodes. These voltages loss indicated high resistances within the stacked MFC, generating a parasitic cross current.

Bioelectricity production from the anodic inoculation of Geobacter sulfurreducens DL-1 bacteria in constructed wetlands-microbial fuel cells.

Environmental pollution problems caused by the use of fossil fuels have led to the search for renewable energy sources to mitigate greenhouse gas emissions. In addition, constructed wetlands-microbial fuel cells (CW-MFC) could contribute to sustainable development, considering that this technology focuses on the production of bioelectricity. One of the main challenges of CW-MFCs is to potentiate their bioelectrochemical performance. Therefore, this research used the Geobacter sulfurreducens DL-1 bacterium (biofilm) as a bioelectrocatalyst to increase bioelectricity generation. For this, three bioreactors were built as CW-MFCs, using Juncus effusus root exudates and Philodendron cordatum macrophytes as endogenous substrates. The biofilm was developed in a nutrient broth acetate fumarate and directly inoculated onto the anodes of each CW-MFC. The results of bioelectrochemical analyses showed that the biofilm generated more bioelectricity when it consumed the exudates of the Juncus effusus macrophyte, resulting in a maximum performance of 107 mW/m2 power density, -361 mV anodic potential, 290 mV cathodic potential, and 124 Ω internal resistance, using a concentration of 27.5 mg/L of total organic carbon as an endogenous substrate. The results determined that the quantity of root exudates consumed by the anodic biofilm is directly related to the production of bioelectricity in CW-MFCs.

Study of a Mexican isolate of Arthrobotrys musiformis (Orbiliales): Predatory behavior and nematocidal activity of liquid culture filtrates against Haemonchus contortus (Trichostrongylidae), protein profile and myco-constituent groups.

A Mexican isolate of the nematophagous fungus Arthrobotrys musiformis was obtained from a soil sample from the Chapultepec ecological reserve zone, in Cuernavaca, Morelos, Mexico. This isolate demonstrated an important predatory activity (74.9%) against the parasitic nematode Haemonchus contortus (L3) and its fungal liquid culture filtrates (LCF) grown in two media showed the following highest nematocidal activities (NA): In Czapek-DoxBroth (CzDoxB) 80.66% and potato-dextrose broth (PDB) 49.84%. Additionally, two major compounds derived from carboxylic acids and two derivates from alkane group were identified by GC-MS. These compounds have been associated to many biological activities. On the other hand, the protein profile analysis by SDS-electrophoresis followed by a zymogram revealed a 10 kDa protein with protease activity. This study provides important information for future experiments focused to explore the potential use of this protein as well as the identified bioactive compounds presents in the LCF as potential candidates against sheep haemonchosis.

[Capacity of the oleaginous yeast Clavispora lusitaniae Hi2 to transform agroindustrial residues into lipids]. / Potencial de la levadura oleaginosa Clavispora lusitaniae Hi2 en la conversión de residuos agroindustriales a lípidos.

BACKGROUND: Single-cell oils obtained from oleaginous microorganisms by using lignocellulosic waste hydrolysates are an alternative for producing biodiesel. AIMS: To isolate a yeast strain able to produce lipids from centrifuged nejayote (CN), hydrolyzed nejayote solids (HNS) and hydrolyzed sugarcane bagasse (HSB). METHODS: In order to identify the yeasts recovered, 26S ribosomal DNA was sequenced. The metabolic profile was assessed by using API20C AUX strips. The nutritional characterization of CN, HNS and HSB was performed by quantifying reducing sugars, total carbohydrates, starch, protein and total nitrogen. The biomass and lipid production ability were evaluated by performing growth kinetics of Clavispora lusitaniae Hi2 in combined culture media. RESULTS: Six oleaginous yeast strains were isolated and identified, selecting C. lusitaniae Hi2 to study its lipids production by using nejayote. The C. lusitaniae Hi2 strain can use glucose, xylose, arabinose, galactose and cellobiose as carbon sources. Cultures of C. lusitaniae Hi2 presented the best biomass (5.6±0.28 g/L) and lipid production (0.99±0.09 g/L) at 20 h of incubation with the CN:HNS media in the 25:75 and 50:50 ratios, respectively. CONCLUSIONS: The use of CN, HNS and HSB for the growth of C. lusitaniae Hi2 is an option to take advantage of these agro-industrial residues and generate compounds of biotechnological interest.

Identification of sugars as root exudates of the macrophyte species Juncus effusus and Philodendron cordatum in constructed wetland-microbial fuel cells during bioelectricity production.

Constructed wetland-microbial fuel cells (CW-MFCs) systems are a sustainable technology capable of producing bioelectricity and treating wastewater simultaneously. It is also possible to obtain bioelectricity from the photosynthetic substrates obtained by the rhizodeposition of macrophytes, where the electroactive microorganisms present in the rhizosphere use these compounds as biofuel. In the present study, the bioelectricity production capacity of Juncus effusus and Philodendron cordatum species was evaluated in a CW-MFC without an external carbon source. The Juncus effusus species showed a higher bioelectrochemical performance, as they recorded a maximum voltage of 399 mV, a power density of 63.7 mW/m2, a volumetric power density of 15.9 W/m3, an internal resistance of 200 Ω, an anodic potential of -368 mV, and a cathodic potential of 229 mV. In addition, different types of carbohydrates in the form of sugars (sucrose, fructose, galactose, and glucose) were quantified by liquid chromatography, with concentrations of 100-450 µg/L. Chromatographic analysis were performed from the root exudates released in the effluent of both species of macrophyte. Sucrose and glucose were the types of sugars that produced the largest amount with portions of up to 35% and 24%, respectively. Sugars are compounds that worked as electron donors for the production of bioelectricity by using endogenous substrates that fed the anodic biofilm. Consumption was 45-55% for sucrose and 40-65% for glucose. Of the different macrophytes evaluated in the CW-MFCs, it was observed that the production of bioelectricity differs mainly due to the quantity of the root exudates released in the rhizosphere.

[Polymorphisms in gene regulatory regions and their role in the physiopathology of complex disease in the post-genomic era]. / Polimorfismos reguladores y su participación en la patogenia de enfermedades complejas en la era posgenómica.

The genomic era is imparting a new impulse to the study of the role of genetic variation in susceptibility to disease. The most common type of genetic variation between individuals is single nucleotide polymorphisms (SNP). The association of SNPs with susceptibility to disease is the current focus of intense research. Recently, the study of SNPs that alter the regulatory mechanisms of gene expression (rSNP) has emerged as a promising field for understanding disease, since this type of variation can have a profound effect on human traits related to susceptibility to disease. The finding and functional characterization of biologically significant rSNPs is advancing our knowledge of genetic determinants for multifactorial disease.

Immunity related genes in dipterans share common enrichment of AT-rich motifs in their 5' regulatory regions that are potentially involved in nucleosome formation.

BACKGROUND: Understanding the transcriptional regulation mechanisms in response to environmental challenges is of fundamental importance in biology. Transcription factors associated to response elements and the chromatin structure had proven to play important roles in gene expression regulation. We have analyzed promoter regions of dipteran genes induced in response to immune challenge, in search for particular sequence patterns involved in their transcriptional regulation. RESULTS: 5' upstream regions of D. melanogaster and A. gambiae immunity-induced genes and their corresponding orthologous genes in 11 non-melanogaster drosophilid species and Ae. aegypti share enrichment in AT-rich short motifs. AT-rich motifs are associated with nucleosome formation as predicted by two different algorithms. In A. gambiae and D. melanogaster, many immunity genes 5' upstream sequences also showed NFkappaB response elements, located within 500 bp from the transcription start site. In A. gambiae, the frequency of ATAA motif near the NFkappaB response elements was increased, suggesting a functional link between nucleosome formation/remodelling and NFkappaB regulation of transcription. CONCLUSION: AT-rich motif enrichment in 5' upstream sequences in A. gambiae, Ae. aegypti and the Drosophila genus immunity genes suggests a particular pattern of nucleosome formation/chromatin organization. The co-occurrence of such motifs with the NFkappaB response elements suggests that these sequence signatures may be functionally involved in transcriptional activation during dipteran immune response. AT-rich motif enrichment in regulatory regions in this group of co-regulated genes could represent an evolutionary constrained signature in dipterans and perhaps other distantly species.

[Prevalence of Salmonella sp. in foods in Tamaulipas, Mexico, during 2005]. / Prevalencia de Salmonella sp en alimentos en el Estado de Tamaulipas durante el año 2005.

OBJECTIVE: To determine the prevalence of Salmonella sp. in foods obtained from Tamaulipas sanitary jurisdictions during 2005. MATERIALS AND METHODS: Several kinds of foods were taken from the State of Tamaulipas from January to December 2005, which were analyzed in the Public Health State Laboratory of Tamaulipas. If the food fulfilled with the acceptance criteria, it was analyzed looking for Salmonella sp. in agreement with NOM-114-SSA1-1994. Positive foods were sent to the National Institute of Epidemiological Reference and Diagnostic (INDRE) to determine Salmonella species and serovariety. Data were collected in a database and analyzed using chi2 and Fisher's exact test in STATA 8.2 software. RESULTS: 24 of 1300 analyzed foods were positives to Salmonella sp. (1.9%, CI 95% 1.2-2.7). By sanitary jurisdiction, Victoria showed the highest prevalence of positive results (3.9%). When the analysis was carried out by "north jurisdictions" versus "south jurisdictions", south jurisdictions showed a high prevalence of Salmonella in foods (0.9% vs. 2.5%, p < 0.05). Sausage was the most contaminated food (20.0%). A higher percentage of positive results was noticed in terrestrial foods than in sea-derived foods (2.3% vs. 0.3%; p < 0.05). In January (5.5%) and May (3.7%) the highest prevalence of positive results was found; without significant difference by year seasons (p > 0.05). The most common bacterial species was Salmonella enterica, serovariety enteritidis, which was found in 58.3% (n=14) of positive foods. CONCLUSIONS: The jurisdictions with the highest prevalence of Salmonella in foods were identified. Terrestrial foods showed more Salmonella contamination. The results show that thanks to epidemiologic surveillance it is possible to identify potential sources of salmonelosis outbreaks. A bigger research effort it is necessary to extent the epidemiologic surveillance activities and their results, by one side toward the kind of foods initially identified as "high risk foods", and by other side, to other regions of Mexico in order to know the distribution of this pathogen and establish adequate preventive measures.

Potencial de la levadura oleaginosa Clavispora lusitaniae Hi2 en la conversión de residuos agroindustriales a lípidos / Capacity of the oleaginous yeast Clavispora lusitaniae Hi2 to transform agroindustrial residues into lipids

AntecedentesLos lípidos obtenidos de microorganismos oleaginosos a partir de hidrolizados de residuos lignocelulósicos son una alternativa para la fabricación de biodiesel.ObjetivosAislar una levadura oleaginosa capaz de producir lípidos a partir de nejayote centrifugado (NC), hidrolizado de sólidos de nejayote (HSN) e hidrolizado de bagazo de caña de azúcar (HBC).MétodosPara identificar los aislamientos recuperados se secuenció el ADN ribosómico 26S. La capacidad metabólica se evaluó mediante tiras API20C AUX. La caracterización nutricional del NC, HSN y HBC se realizó cuantificando azúcares reductores, carbohidratos totales, almidón, proteína y nitrógeno total. La capacidad de producción de biomasa y lípidos de la cepa Clavispora lusitaniae Hi2 se evaluó mediante cinéticas de crecimiento en medios de cultivo formulados a partir de NC, HSN y HBC.ResultadosSe aislaron e identificaron seis cepas de levaduras oleaginosas, siendo C. lusitaniae Hi2 seleccionada para producir lípidos mediante el uso de nejayote. Dicha cepa puede utilizar glucosa, xilosa, arabinosa, galactosa y celobiosa como fuentes de carbono. Los cultivos de C. lusitaniae Hi2 en medio con NC y HSN (en relación 25:75) presentaron la mayor producción de biomasa, 5,6 ± 0,28 g/L; la mayor producción de lípidos, 0,99±0,09 g/L, se obtuvo con una relación 50:50 de estos residuos a las 20 h de incubación.ConclusionesLa utilización de NC, HSN y HBC para el crecimiento de C. lusitaniae Hi2 es una opción para el aprovechamiento de estos residuos y la generación de compuestos de interés biotecnológico. (AU)

BackgroundSingle-cell oils obtained from oleaginous microorganisms by using lignocellulosic waste hydrolysates are an alternative for producing biodiesel.AimsTo isolate a yeast strain able to produce lipids from centrifuged nejayote (CN), hydrolyzed nejayote solids (HNS) and hydrolyzed sugarcane bagasse (HSB).MethodsIn order to identify the yeasts recovered, 26S ribosomal DNA was sequenced. The metabolic profile was assessed by using API20C AUX strips. The nutritional characterization of CN, HNS and HSB was performed by quantifying reducing sugars, total carbohydrates, starch, protein and total nitrogen. The biomass and lipid production ability were evaluated by performing growth kinetics of Clavispora lusitaniae Hi2 in combined culture media.ResultsSix oleaginous yeast strains were isolated and identified, selecting C. lusitaniae Hi2 to study its lipids production by using nejayote. The C. lusitaniae Hi2 strain can use glucose, xylose, arabinose, galactose and cellobiose as carbon sources. Cultures of C. lusitaniae Hi2 presented the best biomass (5.6±0.28 g/L) and lipid production (0.99±0.09 g/L) at 20 h of incubation with the CN:HNS media in the 25:75 and 50:50 ratios, respectively.ConclusionsThe use of CN, HNS and HSB for the growth of C. lusitaniae Hi2 is an option to take advantage of these agro-industrial residues and generate compounds of biotechnological interest. (AU)

Family history and socioeconomic risk factors for non-syndromic cleft lip and palate: a matched case-control study in a less developed country.

INTRODUCTION: From an epidemiological point of view, non-syndromic orofacial clefts are the most common oral congenital deformities worldwide. OBJECTIVE: Family histories were traced and socioeconomic risk factors were identified for non-syndromic cleft lip with or without cleft palate. MATERIAL AND METHODS: A case-control study was carried out with 208 cases of non-syndromic cleft lip with or without cleft palate, and matched by age and sex with 416 controls. Cases were patients attending a referral clinic from 2002 through 2004 in Campeche, Mexico. A questionnaire was administered to collect sociodemographic and socioeconomic variables as well as familial background relevant to non-syndromic cleft lip with or without cleft palate. Conditional logistic regression models were used; adjusted odds ratios and 95% confidence intervals were calculated. RESULTS: In the multivariate model, the following risk factors were identified: 1) low socioeconomic status; 2) birth in the southern region of Campeche state; 3) home delivery or delivery in a publicly funded hospital; 4) occurrence of prior non-syndromic cleft lip with or without cleft palate cases in the father's or mother's family: 5) having a sibling with non-syndromic cleft lip with or without cleft palate; 6) the proband having another malformation, and 7) a history of infections during pregnancy. Prenatal care consisting of vitamin supplementation was a protective factor for non-syndromic cleft lip with or without cleft palate (odds ratio=0.29). CONCLUSIONS: A "social gradient in health" was seen to link oral malformation with diet components, and several socioeconomic and socio-demographic factors broadly encompassed in low socioeconomic status. Further characterization of risk factors will guide the assemblage of a pro-active counseling and prevention program for families at risk for non-syndromic cleft lip and cleft palate.

Dental fluorosis prevalence and severity using Dean's index based on six teeth and on 28 teeth.

To contrast the sensitivity, specificity, and positive-negative predictive values between dental fluorosis prevalence scored on 28 (DF28) and on six permanent teeth (DF6), we undertook a cross-sectional study on 1,538 adolescents (12 and 15 years old) residing in Hidalgo State, Mexico, a naturally fluoridated (>0.7 ppm) area at an elevated altitude (>2,500 m above sea level). Dental fluorosis was scored using Deans modified index. Using the scores obtained for all teeth present (DF28) as a gold standard, we calculated the sensitivity, specificity, positive-negative predictive values, and receiver operating characteristic and concordance index pertaining to the scores based on six teeth (upper incisors and canines). DF28 fluorosis prevalence was 81.7%; based on DF6, it was 58.7% (23% difference). Among 12 year olds, the difference between DF28 and DF6 was 20.1% (84.5 vs. 64.4%); among 15 year olds, it was 25.4% (79.4 vs. 54%). Among girls, it was 23.2% (81.1 vs. 57.9%) and among boys, 22.8% (82.2 vs. 59.4%). The fluorosis community indices were 1.75 (DF28) and 1.11 (DF6). All positive predictive values reached 100% while negative predictive values were below 45%. Concordance between DF28 and DF6 was 53.9%, and kappa coefficient was 0.40. Partial scoring of fluorosis based on esthetically important permanent teeth underestimated prevalence, compared to full-mouth scoring. The decision to use an abridged Dean's index protocol must take into account the number of teeth examined, and which specific teeth are examined, to appraise the benefit of reduced data collection effort against possible information loss.

Factores de riesgo hereditarios y socioeconómicos para labio o paladar hendido no asociados a un síndrome en México: estudio de casos y controles pareado / Family history and socioeconomic risk factors for non-syndromic cleft lip and palate: a matched case-control study in a less developed country

Objetivo. Identificar los factores de riesgo hereditarios y socioeconómicos relacionados con la presencia de labio o paladar hendido no asociados a un síndrome. Materiales y métodos. Se hizo un estudio de casos y controles en el que se incluyeron 208 casos con diagnóstico de labio, paladar hendido o ambos no asociados a un síndrome, los cuales fueron pareados por edad y sexo con 416 controles. Se incluyeron todos los pacientes quirúrgicos atendidos durante el periodo 2002-2004 en el programa estatal de labio o paladar hendido de Campeche, México. Se aplicó un cuestionario en el que se recogió información sobre variables sociodemográficas y socioeconómicas, así como sobre antecedentes hereditarios de labio o paladar hendido no asociados a un síndrome en la familia. Debido a que el diseño fue pareado, el análisis se hizo con regresión logística condicionada. Resultados. En el modelo multivariado para labio o paladar hendido no asociado a un síndrome se identificaron de forma significativa (p<0,05) los siguientes factores de riesgo: nivel socioeconómico bajo (razón de momios, RM=2,02), nacimiento en el sur del estado (RM=3,96), nacimiento en casa (RM=2,51) o nacimiento en hospital público (RM=4,08), antecedentes heredofamiliares paternos (RM=5,38), antecedentes heredofamiliares maternos (RM=4,11), tener otro hijo con labio o paladar hendido en la familia (RM=46,02), presentar algún otro defecto congénito asociado (RM=8,20) e infección en el embarazo (RM=2,90), y como factor protector, el cuidado prenatal y el uso de vitaminas (RM=0,29). Conclusiones. El mayor riesgo en nuestra muestra para labio, paladar hendido o ambos, no asociados a un síndrome, radica en las variables relacionadas con los antecedentes familiares y hereditarios, y las indicadoras de la posición socioeconómica. Se observó un efecto protector del manejo prenatal con vitaminas.

Introduction. From an epidemiological point of view, non-syndromic orofacial clefts are the most common oral congenital deformities worldwide.Objective. Family histories were traced and socioeconomic risk factors were identified for non-syndromic cleft lip with or without cleft palate. Material and methods. A case-control study was carried out with 208 cases of non-syndromic cleft lip with or without cleft palate, and matched by age and sex with 416 controls. Cases were patients attending a referral clinic from 2002 through 2004 in Campeche, Mexico. A questionnaire was administered to collect sociodemographic and socioeconomic variables as well as familial background relevant to non-syndromic cleft lip with or without cleft palate. Conditional logistic regression models were used; adjusted odds ratios and 95% confidence intervals were calculated. Results. In the multivariate model, the following risk factors were identified: 1) low socioeconomic status; 2) birth in the southern region of Campeche state; 3) home delivery or delivery in a publicly funded hospital; 4) occurrence of prior non-syndromic cleft lip with or without cleft palate cases in the father’s or mother’s family: 5) having a sibling with non-syndromic cleft lip with or without cleft palate; 6) the proband having another malformation, and 7) a history of infections during pregnancy. Prenatal care consisting of vitamin supplementation was a protective factor for non-syndromic cleft lip with or without cleft palate (odds ratio=0.29). Conclusions. A “social gradient in health” was seen to link oral malformation with diet components, and several socioeconomic and socio-demographic factors broadly encompassed in low socioeconomic status. Further characterization of risk factors will guide the assemblage of a pro-active counseling and prevention program for families at risk for non-syndromic cleft lip and cleft palate.

Polimorfismos reguladores y su participación en la patogenia de enfermedades complejas en la era posgenómica / Polymorphisms in gene regulatory regions and their role in the physiopathology of complex disease in the post-genomic era

El estudio de la participación de la variación genética en la predisposición a las enfermedades complejas ha cobrado nuevas dimensiones en la era genómica. Los polimorfismos de un solo nucleótido (SNP) son el tipo de variación más común entre individuos y su vinculación con enfermedades es motivo de investigación intensa. En fecha reciente, el estudio de los SNP que afectan la expresión genética (rSNP) ha suscitado mayor interés, ya que las diferencias de la expresión genética entre un sujeto y otro pueden modificar el fenotipo. El descubrimiento y caracterización funcional de los rSNP y el estudio de su frecuencia alélica representan un nuevo campo en la búsqueda de determinantes genéticos de enfermedades multifactoriales.

The genomic era is imparting a new impulse to the study of the role of genetic variation in susceptibility to disease. The most common type of genetic variation between individuals is single nucleotide polymorphisms (SNP). The association of SNPs with susceptibility to disease is the current focus of intense research. Recently, the study of SNPs that alter the regulatory mechanisms of gene expression (rSNP) has emerged as a promising field for understanding disease, since this type of variation can have a profound effect on human traits related to susceptibility to disease. The finding and functional characterization of biologically significant rSNPs is advancing our knowledge of genetic determinants for multifactorial disease.