Impact of SLC22A1 variants rs622342 and rs72552763 on HbA1c and metformin plasmatic concentration levels in patients with type 2 diabetes mellitus.

Type 2 diabetes mellitus (T2DM) is a major global health problem. Response to first-line therapy is variable. This is partially due to interindividual variability across those genes codifying transport, metabolising, and drug activation proteins involved in first-line pharmacological treatment. Single nucleotide polymorphisms (SNPs) of genes SLC22A1, SLC22A2 and SLC22A3 affect metformin therapeutic response in patients with T2DM patients. The present study investigated allelic and genotypic frequencies of organic cation (OCT)1, OCT2, and OCT3 polymorphisms among metformin-treated patients with type 2 diabetes mellitus (T2DM). It also reports the association between clinical and genetic variables with glycated haemoglobin (HbA1c) control in 59 patients with T2DM. Patients were genotyped through real-time PCR (TaqMan assays). Metformin plasmatic levels were determined by mass spectrometry. Neither the analysis of HbA1c control by SNPs in SLC22A1, SLC22A2 and SLC22A3, nor the dominant genotypic model analysis yielded statistical significance between genotypes in polymorphisms rs72552763 (P=0.467), rs622342 (P=0.221), rs316019 (P=0.220) and rs2076828 (P=0.215). HbA1c levels were different in rs72552763 [GAT/GAT, 6.0 (5.7-6.6), GAT/del=6.5 (6.2-9.0), del/del=6.5 (6.4-6.8); P=0.022] and rs622342 [A/A=6.0 (5.8-6.5), A/C=6.4 (6.1-7.7), C/C=6.8 (6.4-9.3); P=0.009] genotypes. The dominant genotypic model found the lowest HbA1c levels in GAT/GAT (P=0.005) and A/A (P=0.010), in rs72552763 (GAT/GAT vs. GAT/del + del/del) and rs622342 (A/A vs. A/C + CC), respectively. There was a significant correlation between HbA1c levels and metformin dosage amongst del allele carriers in rs72552763 (ß1=0.14, P<0.001, r2=0.387), as opposed to GAT/GAT in rs72552763. There were no differences between HbA1c values in the test set and those predicted by machine learning models employing a simple linear regression based on metformin dosage. Therefore, rs72552763 and rs622342 polymorphisms in SLC22A1 may affect metformin response determined by HbA1c levels in patients with T2DM. The del allele of SNP rs72552763 may serve as a metformin response biomarker.

Pharmacogenetics: ethnicity, treatment and health in Latin American populations.

The Ibero-American Network of Pharmacogenetics and Pharmacogenomics (RIBEF) studies Latin American populations to benefit from the implementation of personalized medicine. Since 2006, it has studied ethnicity to apply pharmacogenetics knowledge in autochthonous populations of Latin America, considering ancestral medicine. The meeting 'Pharmacogenetics: ethnicity, Treatment and Health in Latin American Populations' was held in Mexico City, Mexico, and presented the relevance of RIBEF collaboration with Latin American researchers and the governments of Mexico, Spain and the Autonomous Community of Extremadura. The results of 17 years of uninterrupted work by RIBEF, the Declaration of Mérida/T'Hó and the call for the Dr José María Cantú Award for studies focused on the pharmacogenetics of native populations in Latin America were presented.

Prescription of oral antidiabetics in Mexico. A cross-sectional study.

In 2016 diabetes was declared an epidemic and a health emergency in Mexico. As the rationale of the treatment is to achieve target glycemia levels, the appropriateness of the medications used is important. The aim of this study is to learn the pattern of antidiabetic drug prescription and factors associated with inappropriate prescription in Mexico. A retrospective cross-sectional drug utilization study has been conducted. A randomly selected sample was carefully examined. Out of 3600 clinical records of patients diagnosed with type 2 diabetes mellitus (T2DM), 196 records were revised. As far as control is concerned, 36.7% had their glycemia values in the recommended range. A combination of different antidiabetics was the most common pattern observed (60.7%); the most frequent was that of the association of metformin with whatever oral antidiabetics. Prescriptions were considered as inappropriate in 149 cases (76.0%); younger age and lack of nutritional assessment was significantly related to inappropriate prescription. A trend to use more drugs for treating T2DM has been consistently observed. Despite using so many drugs, most of the patients are not controlled. Avoiding inappropriate prescription by following current guidelines may contribute to a better control and, in turn, decrease morbidity and mortality for this cause.

Pharmacogenetics of Metformin Transporters Suggests No Association with Therapeutic Inefficacy among Diabetes Type 2 Mexican Patients.

Mexico has been under official epidemiological alert due to diabetes since 2016. This study presents new information on the frequency and variants of metformin transporters OCT1, OCT2, OCT3, ABCB1, and CYP2C9 variants as well. It also reports the association with HbA1c control on 103 DMT2 patients. They were genotyped through real-time PCR (TaqMan assays) and grouped according to treatment: metformin and metformin + glibenclamide. Metformin plasmatic levels were determined through mass spectrometry. The analysis of HbA1c showed statistical significance across genotypes in polymorphisms rs72552763 (p = 0.022), rs622342 (p = 0.009), rs1128503 (p = 0.021), and rs2032582 (p = 0.009) within the monotherapy group. Bivariate analysis found no association between any polymorphism and HbA1c control. Two logistic regression models accounted for two diplotypes in OCT1 and ABCB1, including statistically significant covariates. The first model yielded significance in age (p = 0.026), treatment period [p = 0.001], BMI ≥ 25 kg/m2 (p = 0.043), and combined therapy (p < 0.001). There was no association with GAT/GAT of rs72552763 or A/A rs622342 in OCT1. The second model yielded significance in age (p = 0.017), treatment period (p = 0.001), BMI ≥ 25 kg/m2 (p = 0.042), and combined therapy (p < 0.001), finding no association with C/C of rs1128503 or G/G of rs2032582 in ABCB1. Our multinomial logistic regression results may benefit future predictive analyses in diabetic populations.

Hydrochlorothiazide use and risk of non-melanoma skin cancer in Spain: A case/non-case study.

OBJECTIVE: In 2018, the Pharmacological Risk Assessment Committee alerted to a potential relationship between accumulated hydrochlorothiazide dosage and the risk of non-melanoma skin cancer. To study this relationship we used data from the Spanish Pharmacovigilance System for Medicinal Products of Human Use. MATERIALS AND METHODS: Following a case search for every thiazide potentially associated with (SMQ/MedDRA) "Malignant Skin Neoplasms and not Otherwise Specified Skin Neoplasms", a series of disproportionality analyses were conducted by estimating the reporting odds ratio (95% confidence interval). Registered adverse drug reactions and disproportionality through the reported odds ratio were the main outcome measures. RESULTS: For basal cell carcinoma, reporting odds ratio was 4.8 (2.2 - 10.7); squamous cell carcinoma 3.2 (0.9 - 10.5); malignant melanoma, 0.8 (0.2 - 3.5). We found both disproportionality and association between hydrochlorothiazide and basal cell carcinoma, but none of these were found regarding malignant skin melanoma. In the case of squamous cell carcinoma, the lower confidence interval limit was below 1, thus the disproportionality value was not statistically significant. The accumulated hydrochlorothiazide dose was 36,714 mg for basal cell carcinoma; 98,288 mg for squamous cell carcinoma; and 38,444 mg for malignant melanoma. CONCLUSION: The results in Spain, where sun exposure is significant, are consistent with the data in the Pharmacological Risk Assessment Committee's alert, which were obtained in Denmark for both basal cell carcinoma and malignant melanoma. However, the results for squamous cell carcinoma did not reach statistical significance, although the reporting odds ratio value suggested a potential relationship between hydrochlorothiazide and squamous cell carcinoma.

Challenges and Opportunities for Clinical Pharmacogenetic Research Studies in Resource-limited Settings: Conclusions From the Council for International Organizations of Medical Sciences-Ibero-American Network of Pharmacogenetics and Pharmacogenomics Meeting.

PURPOSE: The symposium Health and Medicines in Indigenous Populations of America was organized by the Council for International Organizations of Medical Sciences (CIOMS) Working Group on Clinical Research in Resource-Limited Settings (RLSs) and the Ibero-American Network of Pharmacogenetics and Pharmacogenomics (RIBEF). It was aimed to share and evaluate investigators' experiences on challenges and opportunities on clinical research and pharmacogenetics. METHODS: A total of 33 members from 22 countries participated in 2 sessions: RIBEF studies on population pharmacogenetics about the relationship between ancestry with relevant drug-related genetic polymorphisms and the relationship between genotype and phenotype in Native Americans (session 1) and case examples of clinical studies in RLSs from Asia (cancer), America (diabetes and women health), and Africa (malaria) in which the participants were asked to answer in free text their experiences on challenges and opportunities to solve the problems (session 2). Later, a discourse analysis grouping common themes by affinity was conducted. FINDINGS: The main result of session 1 was that the pharmacogenetics-related ancestry of the population should be considered when designing clinical studies in RLSs. In session 2, 21 challenges and 20 opportunities were identified. The social aspects represent the largest proportion of the challenges (43%) and opportunities (55%), and some of them seem to be common. IMPLICATIONS: The main discussion points were gathered in the Declaration of Mérida/T'Hó and announced on the Parliament of Extremadura during the CIOMS-RIBEF meeting in 4 of the major Latin American autochthonous languages (Náhualth, Mayan, Miskito, and Kichwa). The declaration highlighted the following: (1) the relevance of population pharmacogenetics, (2) the sociocultural contexts (interaction with traditional medicine), and (3) the education needs of research teams for clinical research in vulnerable and autochthonous populations.

Bullous pemphigoid associated with the use of dipeptidil peptidase-4 inhibitors: analysis from studies based on pharmacovigilance databases.

Background Bullous pemphigoid has been associated to dipeptidase-4 inhibitors. Objectives Addressing the potential Bullous pemphigoid-dipeptidase-4 inhibitors association based on pharmacovigilance data currently available in Spain in order to obtain a composite disproportionality estimator from all the data generated by the case-non case studies conducted to this date. Setting The Spanish Pharmacovigilance System for Human Use Drugs database. Method Case-non case study based on the Spanish Pharmacovigilance System for Human Use Drugs notifications submitted between 2007 and 2018 (n = 169,280), using the Medical Dictionary for Regulatory Activities term (Preferred Term) 'pemphigoid' for sitagliptin, vildagliptin, saxagliptin, linagliptin, and alogliptin (n = 1952). As negative control, we used acetaminophen, while furosemide was the positive control. A pooled reported odds ratio analysis in the French, Japanese, and Spanish national pharmacovigilance databases was performed. On The Spanish Pharmacovigilance System for Human Use Drugs, we conducted a bullous pemphigoid-metformin association analysis within the period 1982-2018. Main outcome measure Adverse reaction cases in pharmacovigilance databases and the disproportionality through the reporting odds ratio. Results Within The Spanish Pharmacovigilance System for Human Use Drugs, we found 45 cases of bullous pemphigoid in dipeptidase-4 inhibitors patients. Median age was 77 years (range 72-82). The median latency period was 7 months (range 0.23-86). The Bullous pemphigoid-dipeptidase-4 inhibitors association was established with a reporting odd ratio = 70.0 (95% confidence intervals 49.1-10.1). In the combined analysis of the three aforementioned pharmacovigilance databases, the pooled reporting odd ratio was 81.0 (95% confidence intervals 69.5-94.4). Conclusion The composite estimator for the three national pharmacovigilance databases yields clear evidence of a Bullous pemphigoid-dipeptidase-4 inhibitors association, which was statistically significant for both the pharmacological class as a whole and each of the dipeptidase-4 inhibitors agents under investigation. Metformin's role in the incidence of bullous pemphigoid appeared casual rather than causal. No differences between Caucasian and Asian populations were noted.

Randomized Trial of Deep Vein Thrombosis Chemoprophylaxis with Bemiparin and Enoxaparin in Patients with Moderate to High Thrombogenic Risk Undergoing Plastic and Reconstructive Surgery Procedures.

BACKGROUND: Deep vein thrombosis (DVT) is a common complication during postoperative convalescence characterized by hypercoagulability, vascular endothelium damage and blood stasis. It increases noticeably in peri/postoperative phases of surgery procedures. Pulmonary embolism secondary to iliofemoral DVT is a frequent cause of death. METHODS: Adult patients scheduled for plastic and reconstructive surgery (PRSx) with moderate to high thrombogenic risk were selected. We evaluated the efficacy and safety of bemiparin compared to enoxaparin as chemoprophylaxis for DVT. Following balanced general anesthesia techniques, patients were randomly assigned for subcutaneous enoxaparin 40 IU (Group-E) or bemiparin 3500 IU (Group-B) q24h starting 6 h after procedure conclusion for at least 10 days. All patients were evaluated for DVT through Doppler ultrasound mapping of the lower limbs. RESULTS: Seventy-eight patients were evaluated, mostly women (83%), physical status ASA II (59%), ASA III (10%); Caprini's thrombogenic risk score 3-4 (moderate) 58%, 5-6 (high) 29%, > 6 (too high) 13%; demographics, clinical variables and scores were similar between groups. Median drainage time in breast surgery was 4 days in both groups (p = 0.238). In the case of abdominal surgery, median was 14 days in Group-E versus 13 days in Group-B (p = 0.059). No DVT was detected in either group. CONCLUSIONS: DVT was prevented with bemiparin, without significant bleeding increase nor adverse events; moreover, the cost of bemiparin is lower than enoxaparin. Bemiparin can be considered as alternative drug for DVT chemoprophylaxis in PRSx procedures. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Guillain-Barré syndrome and influenza vaccines: current evidence / Síndrome de Guillain-Barré y vacuna antigripal: evidencia actual

PURPUSE: Guillain-Barré Syndrome (GBS) as a consequence of influenza vaccination is a relevant topic, yet to be clarified, which raises concern both amongst health care personnel and the general population. Every study and pharmacovigilance system point to need of further research and the importance of continuous monitoring of safety regarding influenza vaccines. The aim of the present study is to investigate the publication of new data since the realisation of our meta-analysis of GBS and influenza vaccines (published in 2015). METHODS: A systematic revision of PubMed, Embase, and Web of Knowledge (WOS) databases has been carried out. These report observational studies assessing GBS risk after the administration of influenza vaccines from May 2014 up to July 20th, 2017. RESULTS: The research yielded 107 articles. Only three studies met established inclusion criteria and referred to an estimation GBS risk after some influenza vaccine. Two studies investigated GBS risk by the pandemic A/H1N1 vaccine, while only one looked into season vaccines. CONCLUSIONS: The present systematic review, conducted after the publication of our previous meta-analysis, seems to confirm its previous results. Therefore, GBS should be considered an infrequent adverse effect of influenza vaccination, which should not negatively influence its acceptance. Unfortunately, very few of the systematically surveyed studies meeting inclusion criteria. This fact sharply contrasts with the current consensus as to the need of continuously monitoring the safety of influenza vaccines

INTRODUCCIÓN: El síndrome de Guillain-Barré (GBS) después de la administración de la vacuna frente a la gripe es un tema actual que sigue causando preocupación tanto en el personal sanitario como en la población y que permanece sin esclarecer. El objetivo del presente trabajo es investigar la publicación de nuevos datos desde la realización de nuestro metaanálisis sobre el GBS y las vacunas frente a la gripe (publicado en 2015). MÉTODOS: Se ha realizado una revisión sistemática en las bases de datos PubMed, Embase y Web of Science (WOS) de estudios observacionales que evaluarán el riesgo de GBS después de la administración de vacunas influenza, desde mayo de 2014 hasta el 20 de julio de 2017. RESULTADOS: El resultado de las búsquedas fue de 107 artículos. Finalmente, solo 3 estudios cumplían con los criterios de inclusión establecidos y referían una estimación del riesgo de GBS después de alguna de las vacunas antigripales. Dos estudios investigaron el riesgo de GBS con la vacuna pandémica A/H1N1 y un estudio investigó las vacunas estacionales. CONCLUSIONES: Esta revisión sistemática parece confirmar los hallazgos obtenidos en nuestro metaanálisis. El SGB se podría considerar como un posible efecto adverso poco frecuente de las vacuna antigripales, lo cual no debería afectar negativamente en su aceptación. Desafortunadamente, en nuestra revisión sistemática, hemos encontrado muy pocos estudios que cumplieran los criterios de inclusión, este hecho resulta llamativo ya que el consenso actual señala la necesidad de una monitorización continua sobre la seguridad de las vacunas antigripales

Frequency of CYP2C9 (*2, *3 and IVS8-109A>T) allelic variants, and their clinical implications, among Mexican patients with diabetes mellitus type 2 undergoing treatment with glibenclamide and metformin.

The majority of Mexican patients with diabetes mellitus type 2 (DMT2) (67.9-85.0%) are prescribed sulphonylureas (SUs), which are metabolized by cytochrome P450 2C9 (abbreviated as CYP2C9). SUs are a type of oral anti-diabetic compound which inhibit ATP-sensitive potassium channels, thus inducing glucose-independent insulin release by the ß-pancreatic cells. The wide variability reported in SU responses has been attributed to the polymorphisms of CYP2C9. The present study aimed to describe CYP2C9 polymorphisms (*2, *3 and IVS8-109T) within a sample of Mexican patients with DMT2, while suggesting the potential clinical implications in terms of glibenclamide response variability. From a sample of 248 patients with DMT2 who initially consented to be studied, those ultimately included in the study were treated with glibenclamide (n=11), glibenclamide combined with metformin (n=112) or metformin (n=76), and were subsequently genotyped using a reverse transcription-quantitative polymerase chain reaction (PCR), end-point allelic discrimination and PCR amplifying enzymatic restriction fragment long polymorphism. Clinical data were gathered through medical record revision. The frequencies revealed were as follows: CYP2C9*1/*1, 87.5%; *1/*2, 6.5%; *1/*3, 5.2%; and CYP2C9, IVS8-109A>T, 16.1%. Glibenclamide significantly reduced the level of pre-prandial glucose (P<0.01) and the percentage of glycated hemoglobin (%HbA1c; P<0.01) for IVS8-109A>T compared with combined glibenclamide and metformin treatment. Concerning the various treatments with respect to the different genotypes, the percentages obtained were as follows: Glibenclamide A/A, HbA1c<6.5=33.3%; glibenclamide + metformin A/A, HbA1c<6.5=24.6%; glibenclamide A/T, HbA1c<6.5=33.3%; glibenclamide + metformin A/T, HbA1c<6.5=25%; glibenclamide T/T, HbA1c<6.5=100%; and glibenclamide + metformin T/T, HbA1c<6.5=12.5%. Altogether, these results revealed that, although genetically customized prescriptions remain a desirable goal to increase the chances of therapeutic success, within the studied population neither allelic variants nor dosages demonstrated a clear association with biomarker levels. A key limitation of the present study was the lack of ability to quantify either the plasma concentrations of SU or their metabolites; therefore, further, precise experimental and observational studies are required.

Identification of genetic variants in pharmacogenetic genes associated with type 2 diabetes in a Mexican-Mestizo population.

Type 2 diabetes mellitus (T2DM) is one of the most prevalent chronic pathologies in the world. In developing countries, such as Mexico, its prevalence represents an important public health and research issue. Determining factors triggering T2DM are environmental and genetic. While diet, exercise and proper weight control are the first measures recommended to improve the quality of life and life expectancy of patients, pharmacological treatment is usually the next step. Within every population there are variations in interindividual drug response, which may be due to genetic background. Some of the most frequent first line T2DM treatments in developing countries are sulfonylureas (SU), whose targets are ATP-sensitive potassium channels (KATP). Single nucleotide polymorphisms (SNPs) of the KATP coding genes, potassium voltage-gated channel subfamily J member 11 (KCNJ11) and ATP binding cassette subfamily C member 8 (ABCC8) have been associated with SU response variability. To date, there is little information regarding the mechanism by which these SNPs work within Mexican populations. The present study describes the distribution of three SNPs [KCNJ11 rs5219 (E23K), ABCC8 rs757110 (S1369A) and rs1799854 (-3C/T)] among Mestizo Mexican (MM) T2DM patients, and compares it with published data on various healthy subjects and T2DM populations. Through this comparison, no difference in the KCNJ11 rs5219 and ABCC8 rs757110 allelic and genotypic frequencies in MM were observed compared with the majority of the reported populations of healthy and diabetic individuals among other ethnic groups; except for African and Colombian individuals. By contrast, ABCC8 rs1799854 genomic and allelic frequencies among MM were observed to be significantly different from those reported by the 1000 Genomes Project, and from diabetic patients within other populations reported in the literature, such as the European, Asian and Latin-American individuals [T=0.704, G=0.296; CC=0.506, CT=0.397, TT=0.097; 95% confidence interval (CI); P≤0.05]; except for South Asian and Iberian populations, which may reflect the admixture origins of the present Mexican population. This genetic similarity has not been observed in the other Latin-American groups. To the best of our knowledge, this is the first study of ABCC8 rs757110 and rs1799854 SNP frequencies in any Mexican population and, specifically with diabetic Mexicans. Knowledge of the genetic structure of different populations is key to understanding the interindividual responses to drugs, such as SU and whether genotypic differences affect clinical outcome.

[Face-to-face education to optimize knowledge in patients initiating oral anticoagulant treatment (OAT)]. / Intervención educativa individualizada (IEI) cara a cara para optimizar el conocimiento de pacientes que inician tratamiento anticoagulante oral (TAO).

BACKGROUND: Insufficient knowledge of patients about oral anticoagulants that they have been prescribed is recognized as a risk factor for adverse effects. Education of patients under oral anticoagulation may improve quality and control of anticoagulant treatment; limitations of educational interventions include lack of assessment of patients' knowledge. Our goal was to determine the effect of an individualized educational intervention on knowledge of patients who recently started treatment with oral anticoagulants, to assess patients' knowledge, and to analyze factors associated with knowledge acquisition. METHODS: In 49 consecutive patients attending a thrombosis clinic who initiated or re-initiated oral anticoagulant treatment, knowledge about the treatment was assessed by means of a validated questionnaire, before an individualized, face-to-face educational intervention, and at least four weeks after. Educational intervention started after the questionnaire had been answered by patients for the first time. RESULTS: Knowledge level increased by about 50%; the improvement was higher in patients with more years in school. DISCUSSION: Timely acquisition of knowledge about oral anticoagulant drugs is optimized with interventions provided earlier during the patients' treatment. Assessment of knowledge should be performed and instruction should be adapted to patient characteristics such as level of education and availability to receive education.

Prescription patterns of antihypertensives in a community health centre in Mexico City: a drug utilization study.

Hypertension is highly prevalent; in Mexico, the 2012 National Health and Nutrition Survey reported a prevalence of hypertension of 31.5% in the adult population. Pharmacological treatment is the commonest intervention and has been shown to reduce cardiovascular mortality and morbidity, and total mortality. Accordingly, the type and number of antihypertensives used and the outcome - in terms of blood pressure (BP) control - are important. Therefore, our purpose is to learn the pattern of antihypertensive drug prescription and explore the determinants of BP control in an urban population in Mexico. A retrospective cross-sectional drug utilization study was conducted. Medical records from a community health centre were searched to identify those corresponding to patients diagnosed with hypertension; information upon antihypertensives used and control of the disease was carefully retrieved. A logistic regression model was built to know the main determinants of BP control. A sample of 345 clinical records of interest was identified. Most patients received antihypertensives (86.4%); the leading medications used were angiotensin-converting enzyme inhibitors, 63.8%; beta-blockers (26.5%), diuretics (19.8%), angiotensin-receptor blockers (15.8%) and calcium-channel blockers (6.4%). Only the age (≥55 years) and BMI (>30) of the patients, and the age of the doctors (≥55 years), had an important influence on BP control. Obesity is a particular and important determinant of uncontrolled hypertension; it is worth to act on body weight, on an individual basis. As lack of control has been also tied to elderly doctors, an education programme could be envisaged.

Single-cell microinjection assay indicates that 7-hydroxycoumarin induces rapid activation of caspase-3 in A549 cancer cells.

Coumarins have attracted intense interest in recent years due to their apoptogenic effects. The aim of the present study was to determine whether 7-hydroxycoumarin (7-HC) induces changes in caspase-3 (C-3) activity in A549 human lung carcinoma cells. A range of analytical techniques, including colorimetric and fluorometric assays, western blotting, single-cell microinjection, fluorescence microscopy and image analysis were conducted to elucidate the effects of 7-HC. A 24-h exposure to 1.85 mM 7-HC induced a 65% increase in C-3 activity, and a notable conversion of procaspase-3 to C-3, in addition to poly(ADP-ribose)polymerase cleavage. Furthermore, morphological changes associated with apoptosis were observed. Exposure of the cells to 7-HC for 3 or 6 h increased calcium conductance by 27%. By performing the single-cell microinjection of a specific fluorescent substrate of C-3 into previously 7-HC-exposed cells, a typical enzymatic kinetic profile of C-3 activation was identified a number of hours prior to the morphological and biochemical changes associated with apoptosis being observed. These results suggest that the rapid in vivo activation of C-3 is induced by 7-HC, the most relevant biotransformation product of coumarin in humans.

Cystatin C has a dual role in post-traumatic brain injury recovery.

Cathepsin B is one of the major lysosomal cysteine proteases involved in neuronal protein catabolism. This cathepsin is released after traumatic injury and increases neuronal death; however, release of cystatin C, a cathepsin inhibitor, appears to be a self-protective brain response. Here we describe the effect of cystatin C intracerebroventricular administration in rats prior to inducing a traumatic brain injury. We observed that cystatin C injection caused a dual response in post-traumatic brain injury recovery: higher doses (350 fmoles) increased bleeding and mortality, whereas lower doses (3.5 to 35 fmoles) decreased bleeding, neuronal damage and mortality. We also analyzed the expression of cathepsin B and cystatin C in the brains of control rats and of rats after a traumatic brain injury. Cathepsin B was detected in the brain stem, cerebellum, hippocampus and cerebral cortex of control rats. Cystatin C was localized to the choroid plexus, brain stem and cerebellum of control rats. Twenty-four hours after traumatic brain injury, we observed changes in both the expression and localization of both proteins in the cerebral cortex, hippocampus and brain stem. An early increase and intralysosomal expression of cystatin C after brain injury was associated with reduced neuronal damage.

Present status and perspective of pharmacogenetics in Mexico.

Drug costs account for up to 24% of the country's health expenditure and there are 13,000 registered drugs being prescribed. Diabetes is the main cause of death in the country, with over 85% of diabetic patients currently under drug treatment. The importance of knowing interindividual variability in drug metabolism on Mexican populations is thus evident. The purpose of this article is to provide an overlook of the current situation of pharmacogenetic research in Mexico, focusing on drug-metabolizing enzymes, and the possibility of developing a phenotyping cocktail for Mexican populations. So far, 21 pharmacogenetic studies on Mexican population samples (Mestizos and Amerindian) have been published. These have reported interindividual variability through phenotyping and/or genotyping cytochromes: CYP2D6, 2C19, 2C9, 2E1, and phase II enzymes UGT and NAT2. Some cytochromes with important clinical implications have not yet been phenotyped in Mexican populations. The development of a cocktail adapted to them could be a significant contribution to a larger knowledge on drug response variability at a lower price and shorter time. There are validated phenotyping cocktails that present several practical advantages, being valuable, safe, and inexpensive tools in drug metabolism characterization, which require only a single experiment to provide information on several cytochrome activities.

Pulsatile diastolic increase and systolic decrease in arterial blood pressure: their mechanism of production and physiological role.

The diastolic pulsatile increase in arterial blood pressure is shown to occur earlier in the aorta than in other arteries. It is thus not a reflection of the systolic pressure wave, as has been generally assumed, but an independent pressure wave produced by the sequential contraction of the arterial tree. Conversely, a systolic pulsatile decrease in the rate of blood pressure rise is also produced by an active relaxation of the arterial tree. Simultaneously with the pulsatile changes in arterial blood pressure, there are corresponding changes in arterial blood flow. All these cyclic changes are reflex responses to decreasing diastolic and increasing systolic baroreceptor firing rates, respectively. The two reflexes contribute, together with the known compliance of the large arteries and the great arteriolar blood flow resistance, to the steadiness of capillary blood flow throughout the systolic and the much longer-lasting diastolic phases of the cardiac cycle.

Nucleocapsid of rabies virus improve immune response of an inactivated avian influenza vaccine.

The purpose of this study was to determine if nucleocapsid of rabies virus could improve the immune response (humoral and protective) of chickens vaccinated against avian influenza with an inactivated avian influenza experimental vaccine (AIV). On the other hand, AIV with and without NC was compared with an inactivated oil emulsion avian influenza commercial vaccine (CV) virus, currently used in Mexico. Groups of 8 day old chickens were vaccinated intracutaneously with an AIV (group 1); group 2, AIV supplemented with 20 microg of nucleocapsid of rabies virus (NC); Group 3, commercial vaccine (CV) and control groups (4 and 5) with 20 microg of NC and non-infected allantoic fluid, respectively. CV showed a better antibody-mediated response (p < 0.001) after and before challenging; which correlated with the best protection; while NC improved the protection in comparison with group 1. This is the first report on the potential utility of the rabies virus N protein to improve immune response in domestic species.

Activation of protein kinase A stimulates the progesterone-induced calcium influx in human sperm exposed to the phosphodiesterase inhibitor papaverine.

Progesterone induces a fast transient calcium influx in human sperm though the activation of nongenomic receptors. During sperm capacitation, a complex process required for sperm to be able to fertilize the egg, the calcium influx induced by progesterone is enhanced. Sperm capacitation is mediated by an increase in cAMP content and subsequent protein kinase A (PKA) activation. In this work, we examined the effect of increasing intracellular cAMP on the calcium influx induced by progesterone in noncapacitated human sperm. To do this, sperm were exposed to the phosphodiesterase inhibitor papaverine for 5 minutes, a treatment that increased both the cAMP content and the PKA activity several-fold. The calcium influx induced by progesterone was increased by papaverine to levels close to those found in capacitated sperm. This effect was partially inhibited by H89 (48%) and by genistein (41%), and the sum of both inhibitors reduced the stimulating effect of papaverine by 89%. The inhibitory effect of genistein on the progesterone-induced calcium influx could be related to its capability to inhibit the papaverine-stimulated increase in cAMP content and PKA activity. The results presented here suggest that the calcium influx induced by progesterone is up-regulated by the PKA activity.

Human Cementum Protein 1 induces expression of bone and cementum proteins by human gingival fibroblasts.

We recently presented evidence showing that a human cementoblastoma-derived protein, named Cementum Protein 1 (CEMP1) may play a role as a local regulator of cementoblast differentiation and cementum-matrix mineralization. This protein was shown to be expressed by cementoblasts and progenitor cells localized in the periodontal ligament. In this study we demonstrate that transfection of CEMP1 into human gingival fibroblasts (HGF) induces mineralization and expression of bone and cementum-matrix proteins. The transfected HGF cells had higher alkaline phosphatase activity and proliferation rate and they expressed genes for alkaline phosphatase, bone sialoprotein, osteocalcin, osteopontin, the transcription factor Runx2/Cbfa1, and cementum attachment protein (CAP). They also produced biological-type hydroxyapatite. These findings indicate that the CEMP1 might participate in differentiation and mineralization of nonosteogenic cells, and that it might have a potential function in cementum and bone formation.