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In this study, conditions for the ultrasound-assisted extraction (UAE) of soluble polyphenols from Psidium cattleianum (PC) leaves were optimized using response surface methodology (RSM) by assessing the effect of extraction time (X ET = 2, 4, and 6 min), sonication amplitude (X SA = 60, 80, and 100%), and pulse cycle (X PC = 0.4, 0.7, and 1 s). Furthermore, the optimized UAE conditions were compared with a conventional aqueous-organic extraction (AOE) method for extracting total phenolics; moreover, a phenolic profile using HPLC and antioxidant activity (DPPH, ABTS, and FRAP) were also compared. According to the RSM, the best conditions for UAE to extract the highest soluble polyphenol content and yield (158.18 mg/g dry matter [DM] and 15.81%) include a 100% sonication amplitude for 4 min at 0.6 s of pulse cycle. The optimal UAE conditions exhibited an effectiveness of 1.71 times in comparison to the AOE method for extracting total phenolics, in 96.66% less time; moreover, PC leaf extracts by UAE showed higher antioxidant values than AOE. Additionally, gallic, protocateic, chlorogenic, caffeic, coumaric, trans-cinnamic, 4-hydroxybenzoic, and syringic acids, as well as kaempferol were identified in PC leaves under UAE. PC leaf extracts are widely used for therapeutic and other industrial purposes; thus, the UAE proves to be a useful technology with which to improve the yield extraction of PC leaf phytochemicals.

Hibiscus sabdariffa Linn. Malvaceae (HS) is characterized by its edible calyxes. The HS calyxes are widely used for cosmetic, food, and medicinal applications. According to ethnobotanical evidence, decoction, infusion, or maceration extracts from HS calyxes have been used in folk medicine to treat many ailments. Moreover, several in vitro and in vivo studies have demonstrated the pharmacological properties and potential human health benefits of HS consumption. On the other hand, the evaluation of the physiological effects and health benefits of HS in clinical studies is most challenging. Therefore, this narrative review summarizes and discusses the physiological effects and health benefits of HS calyxes reported in clinical trials. Preparations obtained from HS calyxes (extracts, infusions, decoction, teas, beverages, capsules, and pills) are used as non-pharmacological therapies to prevent/control diverse chronic non-communicable diseases. The most-reported HS health benefits are its antihypertensive, antidyslipidemic, hypoglycemic, body fat mass reduction, nephroprotective, antianemic, antioxidant, anti-inflammatory, and anti-xerostomic activities; these effects are associated with the phytochemicals found in HS. Moreover, no adverse effects were reported during the clinical trials. However, clinical studies exhibited some limitations; thus, further studies are required to validate the clinical efficacy of HS in large-scale studies with higher doses and a good experimental design.

The frailty syndrome is a common clinical marker of vulnerability in older adults conducive to an overall decline in inflammatory stress responsiveness; yet little is known about the genetic risk factors for frailty in elderly. Our aim was to investigate the association between the rs2476601 polymorphism in PTPN22 gene and susceptibility to frailty in Mexican older adults. Data included 630 subjects 70 and older from The Coyoacán cohort, classified as frail, pre-frail, and non-frail following Fried's criteria. Sociodemographic and clinical characteristics were compared between groups at baseline and after a multivariate analysis. The rs2476601 polymorphism was genotyped by TaqMan genotyping assay using real-time PCR and genotype frequencies were determined for each frailty phenotype in all participants and subsets by age range. Genetic association was examined using stratified and interaction analyses adjusting for age, sex and variables selected in the multivariate analysis. Disability for day-life activities, depression and cognitive impairment were associated with the risk of pre-frailty and frailty at baseline and after adjustment. Carrying the T allele increased significantly the risk of frailty in patients 76 and older (OR 5.64, 95% CI 4.112-7.165) and decreased the risk of pre-frailty under no clinical signs of depression (OR 0.53; 95% CI 0.17-1.71). The PTPN22 polymorphism, rs2476601, could be a genetic risk factor for frailty as subject to quality of life. This is the first study analyzing such relationship in Mexican older adults. Confirming these findings requires additional association studies on wider age ranges in populations of older adults with frailty syndrome.

Zymomonas mobilis ZM4 is an ethanol-producing microbe that is constitutively tolerant to this solvent. For a better understanding of the ethanol tolerance phenomenon we obtained and characterized two ZM4 mutants (ER79ap and ER79ag) with higher ethanol tolerance than the wild-type. Mutants were evaluated in different ethanol concentrations and this analysis showed that mutant ER79ap was more tolerant and had a better performance in terms of cell viability, than the wild-type strain and ER79ag mutant. Genotyping of the mutant strains showed that both carry non-synonymous mutations in clpP and spoT/relA genes. A third non-synonymous mutation was found only in strain ER79ap, in the clpB gene. Considering that ER79ap has the best tolerance to added ethanol, the mutant alleles of this strain were evaluated in ZM4 and here we show that while all of them contribute to ethanol tolerance, mutation within spo T/ rel A gene seems to be the most important.

The whole-genome sequences of three strains of Rhizobium gallicum reported here support the concept that the distinct nodulation host ranges displayed by the symbiovars gallicum and phaseoli can be largely explained by different symbiotic plasmids., (Copyright © 2017 Bustos et al.)

Inflammation is a key event that is closely associated with the pathophysiology of frailty. The relationship of genetic polymorphisms into inflammatory cytokines with frailty remains poorly understood. The aim of this study was to investigate the association between VNTR polymorphisms of the IL-4 and IL-1RN genes with the risk of frailty. We included a sample of 630 community-dwelling elderly aged 70 and older. Both IL-4 and IL-1RN VNTR polymorphisms were genotyped by the polymerase chain reaction (PCR) method. Mean age was 77.7 years (SD = 6.0) and 52.5 % were women. The participants classified as frail were more likely to be older, had lower MMSE score (p < 0.001), and had more disability for IADL (p < 0.001) and ADL (p < 0.001). Genotypic and allelic frequencies for the IL-4 VNTR polymorphism did not show significant differences between study groups (p > 0.05). However, we just observed a significant difference in the allelic frequencies for the A2 allele of the IL-1RN VNTR polymorphism between frail and nonfrail groups (OR 1.84, 95 % CI 1.08-3.12, p = 0.02). In addition, we analyzed the combined effect of the IL-4 and IL-1RN VNTR polymorphisms and their possible association with frailty, where the combined IL-4 (low) -IL-1Ra (high) genotype was identified as a marker of risk to frailty syndrome (OR 7.86, 95 % CI 1.83-33.69, p = 0.006). Our results suggest that both A2 allele and the combined IL-4 (low) -IL-1Ra (high) genotype might be genetic markers of susceptibility to frailty in Mexican elderly.

It is known that growth hormone (GH) and its receptor (GHR) are expressed in granulosa cells (GC) and thecal cells during the follicular development in the hen ovary, which suggests GH is involved in autocrine/paracrine actions in the female reproductive system. In this work, we show that the knockdown of local ovarian GH with a specific cGH siRNA in GC cultures significantly decreased both cGH mRNA expression and GH secretion to the media, and also reduced their proliferative rate. Thus, we analyzed the effect of ovarian GH and recombinant chicken GH (rcGH) on the proliferation of pre-hierarchical GCs in primary cultures. Incubation of GCs with either rcGH or conditioned media, containing predominantly a 15-kDa GH isoform, showed that both significantly increased proliferation as determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, proliferating cell nuclear antigen (PCNA) quantification and ((3)H)-thymidine incorporation ((3)H-T) assays in a dose response fashion. Both, locally produced GH and rcGH also induced the phosphorylation of Erk1/2 in GC cultures. Furthermore, GH increased IGF-I synthesis and its release into the GC culture incubation media. These results suggest that GH may act through local IGF-I to induce GC proliferation, since IGF-I immunoneutralization completely abolished the GH-induced proliferative effect. These data suggest that GH and IGF-I may play a role as autocrine/paracrine regulators during the follicular development in the hen ovary at the pre-hierarchical stage., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background: Genetic variations of the TCF7L2 gene are associated with the development of Type 2 diabetes (T2D). The associated mutations have demonstrated an adaptive role in some human populations, but no studies have determined the impact of evolutionary forces on genetic diversity in indigenous populations from Mexico. Here, we sequenced and analyzed the variation of the TCF7L2 gene in three Amerindian populations and compared the results with whole-exon-sequencing of Mestizo populations from Sigma and the 1000 Genomes Project to assess the roles of selection and recombination in diversity., Results: The diversity in the indigenous populations was biased to intronic regions. Most of the variation was low frequency. Only mutations rs77961654 and rs61724286 were located on exon 15. We did not observe variation in intronic region 4-6 in any of the three indigenous populations. In addition, we identified peaks of selective sweeps in the mestizo samples from the Sigma Project within this region. By replicating the analysis of association with T2D between case-controls from the Sigma Project, we determined that T2D was most highly associated with the rs7903146 risk allele and to a lesser extent with the other six variants. All associated markers were located in intronic region 4-6, and their r(2) values of linkage disequilibrium were significantly higher in the Mexican population than in Africans from the 1000 Genomes Project. We observed reticulations in both the haplotypes network analysis from seven marker associates and the neighborNet tree based on 6061 markers in the TCF7L2 gene identified from all samples of the 1000 Genomes Project. Finally, we identified two recombination hotspots in the upstream region and 3' end of the TCF7L2 gene., Conclusions: The lack of diversity in intronic region 4-6 in Indigenous populations could be an effect of selective sweeps generated by the selection of neighboring rare variants at T2D-associated mutations. The survivors' variants make the intronic region 4-6 the area of the greatest population differentiation within the TCF7L2 gene. The abundance of selective peak sweeps in the downstream region of the TCF7L2 gene suggests that the TCF7L2 gene is part of a region that is in constant recombination between populations.

Objective: Since vitamin D is an important regulator of muscle function, the effect of vitamin D deficiency on frailty syndrome has been recently studied. This cross-sectional study aimed to determine the association between 25(OH)-vitamin D levels and frailty status in Mexican community-dwelling elderly., Methods: Sample of 331 community-dwelling elderly aged 70 or older, a subset of those included in the "Coyoacán cohort" were included. 25(OH)-vitamin D assay and frailty status were measured., Results: Mean age was 79.3 years and 54.1% were women. Those classified as frail were more likely to have lower Mini-Mental State Examination score (p = 0.015), more disability for instrumental activities of daily living (p < 0.001) and for activities of daily living (p < 0.001). Serum 25(OH)-vitamin D levels were lower in the frail subgroup when compared with the non-frail one (p < 0.001). Multivariate logistic regression analyses showed a significant association between intermediate tertile [odds ratios (OR) = 4.13; 95% confidence intervals (CI) 2.00-8.56] or insufficient tertile (OR = 8.95; 95% CI 2.41-33.30) of vitamin D levels and frailty even after adjusting for potential confounders., Conclusion: These results suggest that older adults with low 25(OH)-vitamin D levels are associated with the probability to being frail compared with those with sufficient vitamin D levels.

Growth hormone (GH) is expressed in several extra-pituitary tissues, including the primary and secondary lymphoid organs of the immune system. In birds, GH mRNA and protein expression show a specific developmental distribution pattern in the bursa of Fabricius (BF), particularly in epithelial and B cells. Changes in the bursal concentration and distribution of locally produced GH during ontogeny suggest it is involved in B cell differentiation and maturation, as well as in a functional survival role in this organ, which may be mediated by paracrine/autocrine mechanisms. Here, we analyzed the anti-apoptotic effect of GH in BF and the intracellular signaling pathways involved in this activity. Also, we studied if this effect was exerted directly by GH or mediated indirectly by IGF-I. Bursal cell cultures showed an important loss of their viability after 4h of incubation and a significant increase in apoptosis. However, treatment with 10nM GH or 40 nM IGF-I significantly increased B cell viability (16.7 ± 0.67% and 13.4 ± 1.12%, respectively) when compared with the untreated controls. In addition, the presence of apoptotic bodies (TUNEL) dramatically decreased (5.5-fold) after GH and IGF-I treatments, whereas co-incubation with anti-GH or anti-IGF-I, respectively, blocked their anti-apoptotic effect. Likewise, both GH and IGF-I significantly inhibited caspase-3 activity (by 40 ± 2.0%) in these cultures. However, the use of anti-IGF-I could not reverse the GH anti-apoptotic effects, thus indicating that these were exerted directly. The addition of 100 nM wortmannin (a PI3K/Akt inhibitor) blocked the GH protective effects. Also, GH stimulated (3-fold) the phosphorylation of Akt in bursal cells, and adding wortmannin or an anti-GH antibody inhibited this effect. Furthermore, GH was capable to stimulate (7-fold) the expression of Bcl-2. Taken together, these results indicate that the direct anti-apoptotic activity of GH observed in the chicken bursal B cell cultures might be mediated through the PI3K/Akt pathway., (Copyright © 2015 Elsevier Inc. All rights reserved.)

A significant number of clinical practice guidelines (CPGs) about the treatment of acne vulgaris in adolescents and adults have been published worldwide. However, little is known about the quality of CPGs in this field. The aim of this study was to appraise the methodological quality of published acne vulgaris CPGs. We performed a systematic review of published CPGs on acne vulgaris therapy from July 2002 to July 2012. Three reviewers independently assessed each CPG using the AGREE II instrument. A standardized score was calculated for each of the six domains. Our search strategy identified 103 citations but just six met our inclusion criteria. Agreement among reviewers was very good: 0.981. The domains that scored better were: "scope and purpose" and "clarity and presentation". Those that scored worse were "stakeholder involvement", "rigor of development", and "applicability". The European and the Malaysian CPGs were the only recommended with no further modifications. In addition, the Mexican, Colombian and the United States guidelines were recommended with provisos, with lower scores regarding stakeholder involvement, rigor of development and applicability. Only two guidelines clearly reported outcome measures for evaluating efficacy or included quality of life outcomes. CPGs varied regarding the consideration of light/laser therapy or consideration of complementary/alternative medicines. None of them included cost considerations of drugs such as systemic isotretinoin. In conclusion, published acne vulgaris CPGs for acne therapy vary in quality with a clear need to improve their methodological rigor. This could be achieved with the adherence to current CPGs development standards.

Growth hormone (GH) has several effects on the immune system. Our group has shown that GH is produced in the chicken bursa of Fabricius (BF) where it may act as an autocrine/paracrine modulator that participates in B-cell differentiation and maturation. The time course of GH mRNA and protein expression in the BF suggests that GH may be involved in development and involution of the BF, since GH is known to be present mainly in B lymphocytes and epithelial cells. In addition, as GH is anti-apoptotic in other tissues, we assessed the possibility that GH promotes cell survival in the BF. This work focused on determining the mechanism by which GH can inhibit apoptosis of B cells and if the PI3K/Akt pathway is activated. Bursal cell cultures were treated with a range of GH concentrations (0.1-100nM). The addition of 10nM GH significantly increased viability (16.7±0.6%) compared with the control and decreased caspase-3 activity to 40.6±6.5% of the control. Together, these data indicate that GH is produced locally in the BF and that the presence of exogenous GH in B cell cultures has antiapoptotic effects and increases B cell survival, probably through the PI3k/Akt pathway., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Neuroprotection is a mechanism within the central nervous system (CNS) that protects neurons from damage as a result of a severe insult. It is known that growth hormone (GH) is involved in cell survival and may inhibit apoptosis in several cell types, including those of the CNS. Both GH and GH-receptor (GHR) genes are expressed in the cerebellum. Thus, we investigated the possible neuroprotective role of GH in this organ, which is very sensitive to hypoxic/ischemic conditions. Endogenous GH levels increased in the brain and cerebellum (30% and 74%, respectively) of 15-day-old chicken embryos exposed to hypoxia during 24h compared to normoxia. In primary embryonic cerebellar neuron cultures treated under hypoxia (0.5% O(2)) and low glucose (1g/L) conditions (HLG) for 1h, GH levels increased 1.16-fold compared to the control. The addition of 1nM recombinant chicken GH (rcGH) to cultures during HLG increased cell viability (1.7-fold) and the expression of Bcl-2 (1.67-fold); in contrast the caspase-3 activity and the proportion of apoptotic cells decreased (37% and 54.2%, respectively) compared to HLG. rcGH activated the PI3K/Akt pathway both under normoxic and HLG conditions, increasing the proportion of phosphorylated Akt (1.7- and 1.4-fold, respectively). These effects were abolished by wortmannin and by immunoneutralization, indicating that GH acts through this signaling pathway. Furthermore, the 15-kDa GH variant (10nM) significantly increased cell viability and decreased caspase-3 activity during HLG condition. Thus GH may act as a paracrine/autocrine neuroprotective factor that preserves cellular viability and inhibits apoptotic cell death., (Copyright © 2012 Elsevier Inc. All rights reserved.)

In bacteria, niche adaptation may be determined by mobile extrachromosomal elements. A remarkable characteristic of Rhizobium and Ensifer (Sinorhizobium) but also of Agrobacterium species is that almost half of the genome is contained in several large extrachromosomal replicons (ERs). They encode a plethora of functions, some of them required for bacterial survival, niche adaptation, plasmid transfer or stability. In spite of this, plasmid loss is common in rhizobia upon subculturing. Rhizobial gene-expression studies in plant rhizospheres with novel results from transcriptomic analysis of Rhizobium phaseoli in maize and Phaseolus vulgaris roots highlight the role of ERs in natural niches and allowed the identification of common extrachromosomal genes expressed in association with plant rootlets and the replicons involved., (Copyright © 2012 Elsevier Inc. All rights reserved.)

The taxonomic position of Phaseolus vulgaris rhizobial strains with available sequenced genomes was examined. Phylogenetic analyses with concatenated conserved genomic fragments accounting for over half of each genome showed that Rhizobium strains CIAT 652, Ch24-10 (newly reported genome) and CNPAF 512 constituted a well-supported group independent from Rhizobium etli CFN 42(T). DNA-DNA hybridization results indicated that CIAT 652, Ch24-10 and CNPAF 512 could correspond to R. etli, although the hybridization values were at the borderline that distinguishes different species. In contrast, experimental hybridization results were higher (over 80%) with Rhizobium phaseoli type strain ATCC 14482(T) in congruence to phylogenetic and ANIm analyses. The latter criterion allowed the reclassification of R. etli strains 8C-3 and Brasil5 as R. phaseoli. It was therefore concluded, based on all the evidence, that the CIAT 652, Ch24-10, and CNPAF 512 strains should be reclassified as R. phaseoli in spite of several common features linking them to R. etli. The R. phaseoli and R. etli speciation process seems to be a more recent event than the speciation that has occurred among other sister species, such as R. leguminosarum-R. etli or R. rhizogenes-R. tropici., (Copyright © 2012 Elsevier GmbH. All rights reserved.)

Sap flow measurements conducted with thermal dissipation probes (TDPs) are vulnerable to natural temperature gradient (NTG) bias. Few studies, however, attempted to explain the dynamics underlying the NTG formation and its influence on the sensors' signal. This study focused on understanding how the TDP signals are affected by negative and positive temperature influences from NTG and tested the novel cyclic heat dissipation (CHD) method to filter out the NTG bias. A series of three experiments were performed in which gravity-driven water flow was enforced on freshly cut stem segments of Fagus sylvatica L., while an artificial temperature gradient (ATG) was induced. The first experiment sought to confirm the incidence of the ATG on sensors. The second experiment established the mis-estimations caused by the biasing effect of the ATG on standard TDP measurements. The third experiment tested the accuracy of the CHD method to account for the ATG biasing effect, as compared with other cyclic correction methods. During experiments, sap flow measured by TDP was assessed against gravimetric measurements. The results show that negative and positive ATGs were comparable in pattern but substantially larger than field NTGs. Second, the ATG bias caused an overestimation of the standard TDP sap flux density of ∼17 cm(3) cm(-2) h(-1) by 76%, and the sap flux density of ∼2 cm(3) cm(-2) h(-1) by over 800%. Finally, the proposed CHD method successfully reduced the max. ATG bias to 25% at ∼11 cm(3) cm(-2) h(-1) and to 40% at ∼1 cm(3) cm(-2) h(-1). We concluded that: (i) the TDP method is susceptible to NTG especially at low flows; (ii) the CHD method successfully corrected the TDP signal and resulted in generally more accurate sap flux density estimates (mean absolute percentage error ranging between 11 and 21%) than standard constant power TDP method and other cyclic power methods; and (iii) the ATG enforcing system is a suitable way of re-creating NTG for future tests.

Background: Most of the DNA variations found in bacterial species are in the form of single nucleotide polymorphisms (SNPs), but there is some debate regarding how much of this variation comes from mutation versus recombination. The nitrogen-fixing symbiotic bacteria Rhizobium etli is highly variable in both genomic structure and gene content. However, no previous report has provided a detailed genomic analysis of this variation at nucleotide level or the role of recombination in generating diversity in this bacterium. Here, we compared draft genomic sequences versus complete genomic sequences to obtain reliable measures of genetic diversity and then estimated the role of recombination in the generation of genomic diversity among Rhizobium etli., Results: We identified high levels of DNA polymorphism in R. etli, and found that there was an average divergence of 4% to 6% among the tested strain pairs. DNA recombination events were estimated to affect 3% to 10% of the genomic sample analyzed. In most instances, the nucleotide diversity (π) was greater in DNA segments with recombinant events than in non-recombinant segments. However, this degree of recombination was not sufficiently large to disrupt the congruence of the phylogenetic trees, and further evaluation of recombination in strains quartets indicated that the recombination levels in this species are proportionally low., Conclusion: Our data suggest that R. etli is a species composed of separated lineages with low homologous recombination among the strains. Horizontal gene transfer, particularly via the symbiotic plasmid characteristic of this species, seems to play an important role in diversity but the lineages maintain their evolutionary cohesiveness.

Growth hormone (GH) is expressed in the chicken bursa of Fabricius (BF), an organ that undergoes three distinct developmental stages: rapid growth (late embryogenesis until 6-8 weeks of age [w]), plateaued growth (between 10 and 15w), and involution (after 18-20w). The distribution and abundance of GH-immunoreactivity (GH-IR) and GH mRNA expression in stromal and non-stromal bursal cells during development, as well as the potential anti-apoptotic effect of GH in bursal cell survival were the focus of this study. GH mRNA expression was mainly in the epithelial layer and in epithelial buds at embryonic day (ED) 15; at 2w it was widely distributed within the follicle and in the interfollicular epithelium (IFE); at 10w it clearly diminished in the epithelium; whereas at 20w it occurred in only a few cortical cells and in the connective tissue. Parallel changes in the relative proportion of GH mRNA expression (12, 21, 13, 1%) and GH-IR (19, 18, 11, <3%) were observed at ED 15, 2w, 10w, and 20w, respectively. During embryogenesis, GH-IR co-localized considerably with IgM-IR, but scarcely with IgG-IR, whereas the opposite was observed after hatching. Significant differences in bursal cell death occurred during development, with 9.3% of cells being apoptotic at ED 15, 0.4% at 2w, 0.23% at 10w, and 21.1% at 20w. Addition of GH increased cultured cell survival by a mechanism that involved suppression (up to 41%) of caspase-3 activity. Results suggest that autocrine/paracrine actions of bursal GH are involved in the differentiation and proliferation of B lymphocytes and in BF growth and cell survival in embryonic and neonatal chicks, whereas diminished GH expression in adults may result in bursal involution., (Copyright 2010 Elsevier Inc. All rights reserved.)

Strains of the same bacterial species often show considerable genomic variation. To examine the extent of such variation in Rhizobium etli, the complete genome sequence of R. etli CIAT652 and the partial genomic sequences of six additional R. etli strains having different geographical origins were determined. The sequences were compared with each other and with the previously reported genome sequence of R. etli CFN42. DNA sequences common to all strains constituted the greater part of these genomes and were localized in both the chromosome and large plasmids. About 700 to 1,000 kb of DNA that did not match sequences of the complete genomes of strains CIAT652 and CFN42 was unique to each R. etli strain. These sequences were distributed throughout the chromosome as individual genes or chromosomal islands and in plasmids, and they encoded accessory functions, such as transport of sugars and amino acids, or secondary metabolism; they also included mobile elements and hypothetical genes. Sequences corresponding to symbiotic plasmids showed high levels of nucleotide identity (about 98 to 99%), whereas chromosomal sequences and the sequences with matches to other plasmids showed lower levels of identity (on average, about 90 to 95%). We concluded that R. etli has a pangenomic structure with a core genome composed of both chromosomal and plasmid sequences, including a highly conserved symbiotic plasmid, despite the overall genomic divergence.

This work centres on the genomic comparisons of two closely-related nitrogen-fixing symbiotic bacteria, Rhizobium leguminosarum biovar viciae 3841 and Rhizobium etli CFN42. These strains maintain a stable genomic core that is also common to other rhizobia species plus a very variable and significant accessory component. The chromosomes are highly syntenic, whereas plasmids are related by fewer syntenic blocks and have mosaic structures. The pairs of plasmids p42f-pRL12, p42e-pRL11 and p42b-pRL9 as well large parts of p42c with pRL10 are shown to be similar, whereas the symbiotic plasmids (p42d and pRL10) are structurally unrelated and seem to follow distinct evolutionary paths. Even though purifying selection is acting on the whole genome, the accessory component is evolving more rapidly. This component is constituted largely for proteins for transport of diverse metabolites and elements of external origin. The present analysis allows us to conclude that a heterogeneous and quickly diversifying group of plasmids co-exists in a common genomic framework.

Background: Oxidative stress has been related to several conditions during pregnancy (preeclampsia, abortions and premature rupture of membranes); it causes higher sensitivity of the endothelial blood vessel constriction and aggravates the endothelium dependent vasodilatación., Objective: To determine the oxidative stress level and histological changes in preeclamptic women's placenta., Patients and Method: Longitudinal and comparative study. There were included 25 patients referred from second level health units (IMSS, ISSSTE and Hospital General de Zacatecas). To evaluate oxidative stress level, a sample of blood and placenta were obtained during delivery and a second sample was taken during mediate puerperium (10 days)., Results: In control group, total lipidic peroxide levels in serum were 135.6 +/- 7.3 nmol of MDA/mL of serum, compared with the group of moderate hypertension, which registered 222.0 +/- 35.15 nmol MDA/mL. Total lipidic peroxides in serum during puerperium for control group were 150.4 +/- 30.8 and 183.3 +/- 18.51 nmol MDA/mL for the group of moderate hypertension. Placental lipoperoxidation for control group was 0.40 +/- 0.03 microg MDNg, and of 0.32 +/- 0.03 microg MDN/g for the group of mild hypertension. Patients of moderate hypertension group showed an increase at 34% on placental lipoperoxidation over control group. Placental histological alterations where characterized by vascular remodeling loss, deposits of proteinaceous material and macrophagic process., Conclusion: Total lipidic peroxide levels in serum increases during preeclampsia. Histological changes refer uterus-placental ischemia that, probably, induces the oxidative stress.

Objective: To demonstrate that the application of etofenamate is effective in management of acute pain., Material and Methods: We conducted a prospective, longitudnal, 6 months trial, which included 22 women and 18 men with intense acute low back pain of mechanical or postural aetiology, patients who had pain of traumatic origin and needed radiographic studies by orthopaedic surgeon were excluded; the study subjects were treated with 1 g etofenamate intramuscularly and the analgesic effect was assessed by visual analog scale every 5 minutes for 30 minutes., Results: Marked improvement in pain at 25 minutes in 35 subjects (87.5%). Pain did not improve in 5 subjects (four men, one woman, 12.5%) at 30 minutes. There were no adverse reactions to medication., Discussion: The single dose of 1 g etofenamate is effective in the management of acute pain. Its use prevented 35 admissions with a cost savings of $70,000 pesos. Applying etofenamate caused satisfaction of the beneficiaries and emergency personnel, this drug could be an alternative treatment in medical services and first-level emergency.

Diverse microbial communities and numerous energy-yielding activities occur in deeply buried sediments of the eastern Pacific Ocean. Distributions of metabolic activities often deviate from the standard model. Rates of activities, cell concentrations, and populations of cultured bacteria vary consistently from one subseafloor environment to another. Net rates of major activities principally rely on electron acceptors and electron donors from the photosynthetic surface world. At open-ocean sites, nitrate and oxygen are supplied to the deepest sedimentary communities through the underlying basaltic aquifer. In turn, these sedimentary communities may supply dissolved electron donors and nutrients to the underlying crustal biosphere.

The authors present the cases of two young patients, a man and a woman, who presented with myocardial infarction, in the absence of ischemic heart disease or stenosis of the coronary arteries. The woman was known to have systemic lupus erythematosus (SLE) for the past 3 years (the immunoglobulin M [IgM] anticardiolipins antibodies were positive), without a history of coronary risk factors. Suddenly she presented with acute chest pain on rest that lasted 4 hours and culminated in anterior wall myocardial infarction. She was admitted to the coronary care unit, where no thrombolysis was given. She did not have echocardiographic evidence of Libman-Sacks endocarditis, but myocardial infarction was evident at the electrocardiogram (ECG). The young man had SLE (the IgM anticardiolipins were absent, but he was positive for lupus anticoagulant antibodies), he was hyperlipidemic, was a moderate smoker and moderately obese, and had no history of ischemic heart disease. He suddenly presented with an acute myocardial infarction documented by ECG, enzymes, and gammagraphy. In both patients, coronary angiography findings were normal and myocardial biopsy did not show evidence of arteritis. The relevance of these cases is the rare association of ischemic heart disease in SLE, with normal coronary arteries and without evidence of arteritis or verrucous endocarditis.

Mediastinoscopy is often utilized for staging bronchogenic carcinoma. Whether it should be used routinely or selectively is controversial. Fifty-four patients with bronchogenic carcinoma were prospectively assigned to one of two groups based on the presence (group A) or absence (group B) of one or more of the following criteria: (1) central location; (2) mediastinal nodal enlargement; (3) involvement of laryngeal nerve; and (4) noncentral location plus linear stranding toward the hilum. Mediastinoscopy was performed on all patients in group A. Thoractomy for definitive staging was performed on those patients in group A with negative mediastinoscopic findings for neoplasm and on all patients in group B. Criteria 1, 2, and 3 were found to be valid; 22 of the 27 patients in group A who had any of these criteria had positive mediastinoscopic findings for neoplasm. Criterion 4 per se was found to be invalif; all seven of the patients in group A who had this isolated finding had negative mediastinoscopic findings for neoplasm and had resectable lesions. Twenty-three of the 27 patients in group B had no mediastinal involvement and had resectable lesions. These data indicate that selective mediastinoscopy using criteria 1 through 3 reduces the number of negative examinations and unnecessary thoracotomies to a minimum.

Percutaneous angioplasty was performed in twenty consecutive patients, with congenital pulmonary valve stenosis. Ages ranged from eight months to thirty-two years (mean 9.5 years old). We achieved a valvular gradient dropping from 91 +/- 39 to 19 +/- 11 mm Hg (P less than 0.001) in early post angioplasty level and it was practically unchanged at three months and one year later. (19 +/- 12, 19 +/- 17 mm Hg) (P less than 0.001). Similar change was observed in the right ventricle systolic pressure which was diminished in a progressive way during the follow-up from 113 +/- 37 to 39 +/- 35 (P less than 0.001), 59 +/- 18 and 53 +/- 25 mm Hg (P less than 0.001) immediately, three months and one year later, respectively. The ratio right ventricle systolic pressure/left ventricle was diminished from 0.96 +/- 29 to 0.63 +/- 0.35 in the early post angioplasty period and later from 0.50 +/- 0.16 and 0.44 +/- 0.22 (P less than 0.001). Only one case had restenosis one year later and we repeated the angioplasty with good results. Most of the patients are asymptomatic, the pulmonary murmur features changed. We observed improvement in electrocardiographic and echocardiographic signs. One patient died of anesthetic complications. The remainder of patients did not have severe complications and they were discharged from 48 to 72 hours after angioplasty. In conclusion, valvuloplasty is an effective procedure in a short and long term basis. We considered valvuloplasty in congenital pulmonary valve stenosis the treatment of choice in this group of patients.

The authors present two cases of Kaposi's hemorrhagic sarcoma in renal transplant patients. The malignant condition appeared 28 and 34 months, respectively, after the transplant operation. There was and acceptable improvement of Kaposi's sarcoma in both patient with radiotherapy despite the fact that the patients continued on immunosuppression with bethametasone and azathioprine. One of the patients showed involvement of the small bowel wall with Kaposi's sarcoma at autopsy. The possible causes of the appearance of this neoplasm on these patients in discussed.