Distribution of genetic variants of oxidative stress metabolism genes: Paraoxonase 1 (PON1) and Glutathione S-transferase (GSTM1/GSTT1) in a population from Southeastern Mexico.

BACKGROUND: Paraoxonase 1 (PON1) and glutathione S-transferases (GSTs) are involved in the biotransformation of xenobiotics. Variation in the enzyme concentration and activity suggests individual differences for the degree of protection against oxidative stress. AIM: This study analysed the distribution of SNPs Q192R, L55M (PON1) and variants in GSTM1 and GSTT1 genes in a population from Southeastern Mexico. SUBJECTS AND METHODS: One hundred and fifty-one Mexican Mestizo healthy volunteers were included. PON1 polymorphisms were determined by Taqman allele discrimination real time-PCR, whereas GSTM1 and GSTT1 genes were determined with a multiplex PCR-based method. RESULTS: All genotypes were in Hardy-Weinberg equilibrium, except for GSTM1. The genotypic distributions of Q192R and L55M were 22% QQ, 48% QR, 30% RR, 62% LL, 34% LM and 4% MM, respectively, whereas the allele frequencies were 0.46 (Q), 0.54 (R), 0.79 (L) and 0.21 (M). The most frequent haplotype was R/L (46.7%). It was found that 31% and 9% of the individuals had the GSTM1 and GSTT1 null genotype, respectively. The frequency of the combined null genotype GSTM1*0/GSTT1*0 was 4.64%. CONCLUSION: The results showed that the frequencies of polymorphisms of PON1, GSTM1 and GSTT1 in the Yucatán population differ to those observed in other ethnic groups and provide useful data for epidemiological studies.

Significance of linkage disequilibrium heterogeneous patterns in the 21q22.3 region for mapping 21 trisomy individuals.

Recombination patterns can be indirectly inferred by means of linkage disequilibrium (LD) estimates, since LD is negatively correlated with genetic distance. However, LD does not necessarily have absolute correspondence with genetic distance. We estimated LD at 5 loci located in the 21q22.3 region. These STRs (D21S1440, D21S168, D21S1260, D21S1446, and D21S1411) covered 8.81 Mb of the 21q22.3 region. They were genotyped by conventional PCR. Similar size samples previously validated by sequencing were used as a genotyping control. Three hundred and sixty-nine individuals (62 families) living in Guadalajara, Mexico, were included. As an inclusion criterion, each family had a positive paternity test by autosomal markers for the CODIS core loci. Two hundred and thirty phase known haplotypes were identified by familial segregation. Only those haplotypes whose frequency was higher than 4% were taken into account for LD estimation, expressed as Lewontin's D' coefficient and Bonferroni's correction P values. For all 5 loci, the genetic distributions were in agreement with Hardy-Weinberg expectations. Heterozygosity and haplotype diversity were ≥ 0.69 and 99.58%, respectively. D21S1440-D21S168 (4.51 cM) and D21S1446-D21S1411 (4.58 cM) marker haplotype frequencies were significantly different from those expected by random distribution. The remaining haplotypes, including those with minimal inter-distance (D21S1260-D21S1446, 1.44 Mb), did not show LD. The 5 STRs at the 21q22.3 region in this Mexican population showed a non-homogeneous LD pattern, which demonstrates that recombination or linkage should not be assumed solely on the basis of genetic distance.

Intra-annual density fluctuations in tree rings are proxies of air temperature across Europe.

Intra-Annual Density Fluctuations (IADFs) are an important wood functional trait that determine trees' ability to adapt to climatic changes. Here, we use a large tree-ring database of 11 species from 89 sites across eight European countries, covering a climatic gradient from the Mediterranean to northern Europe, to analyze how climate variations drive IADF formation. We found that IADF occurrence increases nonlinearly with ring width in both gymnosperms and angiosperms and decreases with altitude and age. Recently recorded higher mean annual temperatures facilitate the formation of IADFs in almost all the studied species. Precipitation plays a significant role in inducing IADFs in species that exhibit drought tolerance capability, and a growth pattern known as bimodal growth. Our findings suggest that species with bimodal growth patterns growing in western and southern Europe will form IADFs more frequently, as an adaptation to increasing temperatures and droughts.

The cover crop determines the AMF community composition in soil and in roots of maize after a ten-year continuous crop rotation.

Intensive agricultural practices are responsible for soil biological degradation. By stimulating indigenous arbuscular mycorrhizal fungi (AMF), cover cropping enhances soil health and promotes agroecosystem sustainability. Still, the legacy effects of cover crops (CCs) and the major factors driving the AM fungal community are not well known; neither is the influence of the specific CC. This work describes a field experiment established in Central Spain to test the effect of replacing winter fallow by barley (Hordeum vulgare L.) or vetch (Vicia sativa L.) during the intercropping of maize (Zea mays L.). We examined the community composition of the AMF in the roots and rhizosphere soil associated with the subsequent cash crop after 10 years of cover cropping, using Illumina technology. The multivariate analysis showed that the AMF communities under the barley treatment differed significantly from those under fallow, whereas no legacy effect of the vetch CC was detected. Soil organic carbon, electrical conductivity, pH, Ca and microbial biomass carbon were identified as major factors shaping soil AMF communities. Specific AMF taxa were found to play a role in plant uptake of P, Fe, Zn, Mn, and Cd, which may shed light on the functionality of these taxa. In our conditions, the use of barley as a winter CC appears to be an appropriate choice with respect to promotion of AMF populations and biological activity in agricultural soils with intercropping systems. However, more research on CC species and their legacy effect on the microbial community composition and functionality are needed to guide decisions in knowledge-based agriculture.

Molecular characterization of a patient with 3p deletion syndrome and a review of the literature.

3p deletion syndrome is a rare disorder involving developmental delay, dysmorphic physical features, and growth retardation. Molecular mapping of several cases in the literature have identified a critical region on chromosome 3p26. We present a child patient with characteristic features of 3p deletion syndrome and a de novo unbalanced translocation involving chromosomes 3 and 13. Fine mapping of this rearrangement using fluorescence in situ hybridization (FISH) and array-based comparative genomic hybridization (aCGH) revealed an unbalanced abnormality including a 4.5 Mb terminal deletion of chromosome 3p, telomeric to ITPR1 on 3p26.2, which was not previously identified with routine cytogenetic analysis. In addition, these investigations confirmed and refined the boundaries of a 26.5 Mb deletion of chromosome 13. This study confirms the minimal candidate region for 3p deletion syndrome, provides further evidence implicating haploinsufficiency of CNTN4 in the disorder, and demonstrates the utility of high-resolution investigations of rare chromosomal rearrangements.

Influence of donor age on survival in liver transplantation due to hepatitis C virus.

Cirrhosis secondary to hepatitis C virus (HCV) is one of the most frequent indications for liver transplantation. During recent years, the age of donors has increased, which has led to a worse prognosis for persons undergoing transplantations because of this virus. In this study, we analyzed the 93 transplantations performed during a 6-year period (2000-2005) due to HCV, dividing them into 2 groups according to donor age: <60 years (group A) and >/=60 years (group B). We examined graft and recipient survivals with a mean follow-up of 34 months. Recipient survival among group A was 61% compared with 57% among Group B, the difference being greater if we excluded the initial months after transplantation, since this eliminated the complications inherent to the intervention. Graft survival, according to the Knodell histological activity index, was summarized as: 55.7% histological recurrence, 16.7% fibrosis, and 21% cirrhosis among group A versus 65.6%, 25%, and 18.7%, respectively, among group B. In conclusion, there was improved survival and disease progression was slower among group A compared with group B, suggesting that donor age was an important factor; patient and graft survivals fell progressively with increased donor age.

Efficacy and safety of mycophenolate mofetil monotherapy in liver transplant patients with renal failure induced by calcineurin inhibitors.

OBJECTIVE: To assess the efficacy and safety of mycophenolate mofetil (MMF) monotherapy in liver transplant recipients with renal failure secondary to the use of calcineurin inhibitors (CNIs). MATERIALS AND METHODS: Thirty-one patients on MMF monotherapy with creatinine levels >1.3 mg/dL, previously immunosuppressed with CNIs and MMF, were analyzed. Conversion was started in patients with no acute or chronic rejection episodes and stable liver chemistry. CNI doses were reduced by 25% every 2 to 3 months, or to 50% if the dose was lower than 1 mg/d of tacrolimus or 50 mg/d of cyclosporine. Different variables were recorded from the time that conversion to monotherapy was decided, on the discontinuation day of the calcineurin inhibitor, and during the follow-up. RESULTS: Mean times from transplant to conversion ranged from 14 to 186 months. The minimum follow-up time in monotherapy was 12 months. Renal function improved at 6 months in 70% of cases and at 12 months in 69.6%. Patients with no renal function improvement maintained stable creatinine values. There were no rejection episodes, graft losses, or deaths. No leukopenia occurred, and triglyceride and uric acid values improved. CONCLUSIONS: MMF monotherapy is a safe alternative in patients with posttransplant renal failure secondary to the use of CNIs. Renal function improvement was achieved in almost 70% of patients at 12 months, and creatinine values were maintained in all other patients. The risk of rejection due to the slow tapering of CNIs is minimum.

[Accuracy and reliability between glucose meters: A study under normal clinical practice conditions]. / Exactitud y concordancia entre glucómetros: un estudio en condiciones habituales de práctica clínica.

INTRODUCTION: The glucose meters usually show a high accuracy, and in clinical practice, capillary and plasma glucose (PG) are used interchangeably. However, many variables can affect the validity of these devices. The aim of this study was to determine the accuracy and reliability of 3 glucose meters that are currently used in a primary care centre. MATERIAL AND METHODS: A sample of venous blood and a drop of capillary blood were obtained from 59 participants. The drop was analysed in 3 glucose meters: 2 FreeStyle® Optium (OP1 and OP2), and one Accu-Chek® Aviva. The PG acted as the reference value, and the haematocrit and plasma levels of urea, bilirubin, uric acid and triglycerides were also analysed. We used the Passing-Bablok regression for accuracy and the intraclass correlation coefficient and the Bland-Altman method for reliability. The current American Diabetes Association standard of a total error of±5% was applied. RESULTS: Differences in mean±standard deviation (mg/dL) and the systematic error were 5.8±7 and 5.8% (OP1); 6.2±8 and 5.9% (OP2); 8.3±8 and 6.3% (Accu-Chek®). The OP1/OP2 pair showed the highest level of reliability, with an intraclass correlation coefficient=0.97, bias=-0.4mg/dL, and a width of the 95% limits of agreement of 28.6mg/dL. The highest levels of accuracy and reliability were observed in high glucose ranges (PG≥126mg/dL). CONCLUSIONS: Despite their clinically acceptable mean difference compared to the PG, the 3 glucose meters did not fulfill the current American Diabetes Association standard. The regular performance of quality control tests of these devices is recommended.

Biliodigestive anastomosis in liver transplantation: review of 13 years.

Hepaticojejunostomy is a good alternative technique for biliary reconstruction in liver transplantation. Among 517 liver transplants performed between March 1992 and July 2005, 33 involved hepaticojejunostomy, namely, 18 men and 12 women of average age: 44.8 years. The main cause for this technique was retransplant (n = 10), secondary biliary cirrhosis (n = 5), alcoholic cirrhosis (n = 5), HCV cirrhosis (n = 2), primary biliary cirrhosis (n = 1), cryptogenic cirrhosis (n = 1), sclerosing cholangitis (n = 3), fulminant liver failure (n = 1), autoimmune cirrhosis (n = 1), and insulinoma metastasis (n = 1). Choledochojejunostomy was performed for all Roux-en-Y loops, with an average cold ischemia time of 361.16 minutes (180-780). The biliary complications were biliary fistula in four cases (13.3%), including two who required surgery; stenosis of the anastomosis in two cases (6.6%) including one diagnosed by HIDA that resolved with medical treatment and the other, diagnosed by cholangio-MRI, requiring a new hepaticojejunostomy; and biliary peritonitis in three cases (10%), all of whom required surgery. The vascular complications were thrombosis of the hepatic artery (n = 1), which required retransplantation, and pseudoaneurysm of hepatic artery (n = 1). No biliary complications occurred. The 6-month patient survival was 80% and the 6-month graft survival was 77%; no patient died due to biliary complications. Hepaticojejunostomy is a technique with higher morbidity than choledocho-choledochostomy, but it is the best alternative when the latter is not possible.

Scoring guide when deciding to accept an organ for a liver transplant.

UNLABELLED: Our objective was establish a scoring system that allows a donor to be evaluated quickly and easily using a set of variables that are evaluated prior to the donation and another set that are evaluated during surgery. MATERIALS AND METHODS: Prior to the donation we analyzed age, medication requirements, natremia, hepatic biochemistry, gas levels, days in ICU, history of hypertension, and weight. A value of 40% was allocated to this group of factors. During the transplant we assessed the characteristics of the organ-shine, consistency, surface, edge, color, presence of steatosis, and atheromatosis. A value of 60% was allocated to this set. We established a scale of 1 to 10, only accepting organs scoring 5 or more points. Those grafts that received a score between 5 and 7.5 points were called suboptimal and those with over 7.5 points, optimal. We prospectively analyzed 133 donors whose organs were implanted. RESULTS: The survival rate at 1 year was 85%, and the rejection rate was 12%. The incidence of primary graft dysfunction was 8.2% (n = 11) and that of primary graft nonfunction 2.2% (n = 3). The incidence of primary graft dysfunction was greater within the group with fewer points (suboptimal). There were no differences between the optimal and suboptimal groups in terms of primary malfunction, survival, or rejection rate. CONCLUSIONS: The score provided a guide to decide whether to accept viable organs for implantation, given that the point system was obtained quickly and easily. When greater than 5, it correlated with low rates of primary nonfunction (<3%) and of primary graft dysfunction (<15%), with acceptable survival at 1 year (>80%) and acute rejections rate (<15%).

Efficacy and safety of mycophenolate mofetil as part of induction therapy in liver transplantation.

AIMS: To report our experience with mycophenolate mofetil (MMF) for induction and maintenance therapy to prevent acute liver transplant rejection. METHODS: A retrospective analysis of 66 elective, noncombined liver transplant patients treated beginning de novo MMF and follow for a minimum of 2 years. Thirty-nine of the 66 cases received MMF, calcineurin inhibitors, and steroids. In 11 cases daclizumab was added; in 16 daclizumab was added without steroids. RESULTS: The global survival rate was 91% at 6 months, 89.4% at 1 year, and 87.9% after 2 years. Acute rejection episodes were observed in six patients (9.1%). All episodes responded to corticoids. Toxicity possibly, probably, or partially related to MMF was observed in 35 patients (53%) with definitive suspension required in 13 cases (20%), with dose reduction or temporary suspension in 22 (33%). Hematological toxicity associated with MMF was observed in 12 patients (18%), leading to definitive suspension in two patients (3.03%), temporary suspension in two cases (3.03%), and dose reduction in eight cases (12%). Opportunistic infection was observed in seven cases (10%). Gastrointestinal toxicity was mild and infrequent (five cases, 7.5%). CONCLUSION: Regimens containing MMF reduce rejection episodes with high survival rates and low toxicity.

[Intracytoplasmic crystals and Fanconi syndrome in a patient with IgA kappa myeloma]. / Cristales intracitoplasmáticos y síndrome de Fanconi en un paciente con mieloma IgA kappa.

A 45 year old man with IgA-Kappa myeloma had adult Fanconi Syndrome. Examination of renal biopsy revealed lesions in proximal tubules without glomerular lesions and without intratubular casts. By electron microscopy cytoplasmic crystalline inclusions were observed in renal proximal tubular epithelium. Increased plasma cells (28%) in bone marrow aspiration also contained crystalline inclusions. The treatment of myeloma produced partial remission of proliferative disease and Fanconi syndrome. We discuss the pathogenesis of Fanconi syndrome induced by light chains as well as the composition of crystalline deposits and the effects of treatment on Fanconi Syndrome.

[Bladder transitional cell carcinoma rating, systematization of grading and value of DNA ploidy]. / Contribución a la categorización de los CCT de vejiga, sistemátización de la gradación y utilidad de la ploidía de ADN.

UNLABELLED: TCCs are an heterogenous group of tumors with an uncertain biologic behaviour, especially intermediate grade (G2). Histologic grade and pathologic stage have revealed only partially useful on predicting the outcome. OBJECTIVE: Search and statement of objective and cuantitative parameters able to define prognostic subgroups to TCCs. MATERIAL AND METHOD: We studied consecutive 106 patients with TCC in order to: 1) Identify every variable with independent predictive value in classifying cases of TCC in a three (1,2,3) or two (high/low) grades systems. 2) Make a correlation between DNA ploidy obtained by image analysis and DNA ploidy and S-phase obtained by flow cytometry. RESULTS: Every variable used to define the histologic grade showed significative correlation with both gradation systems. In multivariate analysis, the presence of superficial cells and the mitotic counts revealed us the most valuable variables in predicting the histologic grade. DNA-ploidy (both obtained by static an flow cytometry) correlated well with grade, stage, growth pattern and necrosis, whereas S-phase did so with grade, mitotic index and DNA ploidy. Image cytometry showed similars results to those of flow cytometry and also was able to detect aneuploidy when an situ carcinoma or dysplasia were present in the adyacent mucosa.

[Value of Markovian nuclear texture to predict progression in surface transitional cell carcinoma of the bladder]. / Utilidad de las texturas nucleares Markovianas en la predicción de la progresión en los CCT superficiales de vejiga.

The aim of this work has been to determine if the DNA and nuclear Markovian textures of tissue sections evaluated by image cytometry correlate with the histologic grade and the progression probability of superficial transitional carcinoma of the bladder. In our study, DNA ploidy is related to histologic grade in that aneuploidy frequency increases with a higher grade of malignancy. Image analyses of superficial TCC tissue sections of the bladder, has allowed us to identify "sub-visual parameters" as well as nuclear textures that according to our results can be useful in clarifying the evolutive behaviour of these tumours. Two Markovian textures that identify entropy (TXI) and mean internal contrast (TXB) allow to discriminate between histologic grades as well as progression or non-progression. In conclusion, image analysis cytometry of paraffin embedded tissue sections of TCC of the bladder supplies densitometric parameters related to grade and provides valuable information for the prediction of progression. Quantification of chromatin pattern description in Feulgen-stained nuclei using the Markovian method can be useful in this context.