The Pathological Links between Adiposity and the Carpal Tunnel Syndrome

An association between obesity and carpal tunnel syndrome is found in many epidemiological studies. Therefore, there is a need to evaluate the physiopathological links that could explain the association between these two entities. Ectopic adipose tissue is responsible for metabolic syndrome and inflammation, and is a major risk factor for diabetes and cardiovascular diseases. Taking these elements into consideration, we conducted an extensive literature revision of the subject, considering as ectopic fat-related mechanisms the following: (a) the direct compression and the association with the metabolic syndrome of the fat deposition around the wrist, (b) the insulin resistance, dyslipidemia, inflammatory, and oxidative mechanisms related to the central deposition of the fat, (c) the impaired muscle contraction and metabolism related to myosteatosis. Each section presents the cellular pathways which are modified by the ectopic deposition of the adipose tissue and the impact in the pathogeny of the carpal tunnel syndrome. In conclusion, the experimental and clinical data support the epidemiological findings. Efforts to reduce the obesity epidemics will improve not only cardio-metabolic health but will reduce the burden of the disability-free life expectancy due to the carpal tunnel syndrome.     

Screening for microdeletions in human Y chromosome--AZF candidate genes and male infertility

About 30% of couple infertilities are of male origin, some of them caused by genetic abnormalities of the Y chromosome. Deletions in AZF region can cause severe spermatogenic defects ranging from non-obstructive azoospermia to oligospermia. The intracytoplasmatic sperm injection technique (ICSI) is rapidly becoming a versatile procedure for human assisted reproduction in case of male infertility. The use of ICSI allows Y chromosome defects to be passed from father. The goal of our study is to evaluate the frequency of microdeletions in the long arm of Y chromosome, within the AZF regions, in these cases of infertilities, using molecular genetics techniques. Thirty infertile men with azoospermia or oligozoospermia, determined by spermogram, were studied after exclusion of patients with endocrine or obstructive causes of infertility. Peripheral blood DNA was extracted from each patient, then amplified by multiplex PCR with STS genomic markers from the Y chromosome AZF zones. Each case was checked by multiplex PCR through coamplification with the SRY marker. Three men with microdeletions of the long arm of the Y chromosome were diagnosed among the 30 patients, corresponding to a proportion of 10%. The relatively high proportion of microdeletions found in our population suggest the need for strict patient selection to avoid unnecessary screening for long arm Y chromosome microdeletions. The molecular diagnostics was performed according to the current European Academy of Andrology laboratory guidelines for molecular diagnosis of Y chromosomal microdeletions.     

Characterization of bacterial community associated to biofilms of corroded oil pipelines from the southeast of Mexico

Microbial communities associated to biofilms promote corrosion of oil pipelines. The community structure of bacteria in the biofilm formed in oil pipelines is the basic knowledge to understand the complexity and mechanisms of metal corrosion. To assess bacterial diversity, biofilm samples were obtained from X52 steel coupons corroded after 40 days of exposure to normal operation and flow conditions. The biofilm samples were directly used to extract metagenomic DNA, which was used as template to amplify 16S ribosomal gene by PCR. The PCR products of 16S ribosomal gene were also employed as template for sulfate-reducing bacteria (SRB) specific nested-PCR and both PCR products were utilized for the construction of gene libraries. The V3 region of the 16S rRNA gene was also amplified to analyse the bacterial diversity by analysis of denaturing gradient gel electrophoresis (DGGE). Ribosomal library and DGGE profiles exhibited limited bacterial diversity, basically including Citrobacter spp., Enterobacter spp. and Halanaerobium spp. while Desulfovibrio alaskensis and a novel clade within the genus Desulfonatronovibrio were detected from the nested PCR library. The biofilm samples were also taken for the isolation of SRB. Desulfovibrio alaskensis and Desulfovibrio capillatus, as well as some strains related to Citrobacter were isolated. SRB consists in a very small proportion of the community and Desulfovibrio spp. were the relatively abundant groups among the SRB. This is the first study directly exploring bacterial diversity in corrosive biofilms associated to steel pipelines subjected to normal operation conditions.     

A versatile strategy to define the phosphorylation preferences of plant protein kinases and screen for putative substrates

Most signaling networks are regulated by reversible protein phosphorylation. The specificity of this regulation depends in part on the capacity of protein kinases to recognize and efficiently phosphorylate particular sequence motifs in their substrates. Sequenced plant genomes potentially encode over than 1000 protein kinases, representing 4% of the proteins, twice the proportion found in humans. This plethora of plant kinases requires the development of high-throughput strategies to identify their substrates. In this study, we have implemented a semi-degenerate peptide array screen to define the phosphorylation preferences of four kinases from Arabidopsis thaliana that are representative of the plant calcium-dependent protein kinase and Snf1-related kinase superfamily. We converted these quantitative data into position-specific scoring matrices to identify putative substrates of these kinases in silico in protein sequence databases. Our data show that these kinases display related but nevertheless distinct phosphorylation motif preferences, suggesting that they might share common targets but are likely to have specific substrates. Our analysis also reveals that a conserved motif found in the stress-related dehydrin protein family may be targeted by the SnRK2-10 kinase. Our results indicate that semi-degenerate peptide array screening is a versatile strategy that can be used on numerous plant kinases to facilitate identification of their substrates, and therefore represents a valuable tool to decipher phosphorylation-regulated signaling networks in plants.     

Granulocyte-macrophage colony stimulating factor is anabolic and interleukin-1β is catabolic for rat articular chondrocytes

Objective: To study the effects of GM-CSF and IL-1β, both implicated in tissue damage in arthritis, on articular chondrocyte proliferation and metabolism, and to explore their agonist/antagonist effects. Methods: Chondrocytes were obtained from 1-month-old rats. First-passage monolayers were incubated for 24 h with or without GM-CSF and/or IL-1β, and labeled with ³H-thymidine, ³⁵S–SO₄ and ¹⁴C-proline. Proteoglycan and collagen synthesis were analyzed by liquid chromatography and SDS–PAGE. Gene expression was measured by RT-PCR. Results: IL-1β exerts potent, and GM-CSF weak, inhibitory effects on DNA synthesis. GM-CSF strongly stimulates, and IL-1β inhibits, proteoglycan and collagen synthesis. IL-1β suppresses the effect of GM-CSF, and increases the release of radioactive molecules from pre-labeled cartilage fragments; GM-CSF decreases the IL-1β-induced effect. Interestingly, both cytokines induce the expression of each other’s gene. Conclusions: IL-1β appears to be a catabolic and anti-anabolic agent for chondrocytes, whereas GM-CSF is mainly anabolic, and blocks the IL-1β-induced catabolic effect. It is postulated that both agents are implicated in inflammation: IL-1β promotes tissue catabolism and destruction, whereas GM-CSF enhances tissue reconstruction.     

Investigation on Crude and High-Temperature Heated Coffee Oil by ATR-FTIR Spectroscopy along with Antioxidant and Antimicrobial Properties

The coffee oil has a promising potential to be used in food industry, but an efficient use, especially in products that required high-temperature heating, depends on its chemical composition and the changes induced by processing. Since there is little information on this topic, the aim of our study was to investigate the crude green and roasted coffee oil (GCO, RCO) and heated (HGCO, HRCO) for 1 h at 200°C, by Fourier Transform Infrared (FTIR) spectroscopy and in terms of antioxidant and antimicrobial properties. The results of FTIR spectroscopy revealed that no statistically significant differences (one-way ANOVA, p>0.05) in the oxidative status of GCO and RCO were found. The coffee oils heating induced significant spectral changes in the regions 3100–3600 cm^–1, 2800–3050 cm^–1 and 1680–1780 cm^–1 proved by the differences in the absorbance ratios A 3009 cm⁻¹/A 2922 cm⁻¹, A 3009 cm⁻¹/A 2853 cm⁻¹, A 3009 cm⁻¹/A 1744 cm⁻¹, A 1744 cm⁻¹/A 2922 cm⁻¹. These alterations were related to the reduction of the unsaturation degree due to primary and secondary oxidation processes of the lipid fraction. The radical scavenging ability of oils investigated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay revealed that the IC50 value of GCO was significantly lower than of RCO (p<0.05). The IC50 values of crude coffee oils were lower than those of heated samples. The antioxidant activity of oils was attributed to both antioxidant compounds with free-radical scavenging capacity and to lipids oxidation products generated by heating. In the first 6 h of incubation, the inhibitory activity of crude oils against E. coli and E. faecalis was not significantly different to the control (p>0.05). Also, HGCO and HRCO showed significantly different inhibitory potential related to the control (p<0.05). The heating induced statistically significant decreases in the effectiveness of coffee oils against the tested bacteria. GCO proved to be the most effective among investigated coffee oils against the tested bacteria.     

Testing the hybrid superiority hypothesis in crested and marbled newts

We tested the hybrid superiority hypothesis in the zone of overlap and hybridization of the newts Triturus cristatus and T. marmoratus. To do so, we compared size, age, and growth-related parameters in F₁ hybrids and both parental species in Mayenne, France. We found significant differences in snout-vent length (SVL), body mass and average lifespan between the parental species and hybrids, increasing from T. cristatus – T. marmoratus – hybrids. The relation between age and SVL fitted von Bertalanffy's growth model and showed that SVL_max was significantly larger in hybrids than in the parental species, while the growth coefficient was lower in hybrids and T. marmoratus than in T. cristatus. Triturus cristatus appears to be the better competitor, since it attains sexual maturity faster and thus achieves more annual breeding opportunities. At the evolutionary level, the observed heterosis appears not to have further consequences as the hybrids are largely infertile. Our results support the hypothesis raised for the genus Triturus, that infertile hybrids allocate resources to growth.     

Aldosterone stimulates vacuolar H(+)-ATPase activity in renal acid-secretory intercalated cells mainly via a protein kinase C-dependent pathway

Urinary acidification in the collecting duct is mediated by the activity of H(+)-ATPases and is stimulated by various factors including angiotensin II and aldosterone. Classically, aldosterone effects are mediated via the mineralocorticoid receptor. Recently, we demonstrated a nongenomic stimulatory effect of aldosterone on H(+)-ATPase activity in acid-secretory intercalated cells of isolated mouse outer medullary collecting ducts (OMCD). Here we investigated the intracellular signaling cascade mediating this stimulatory effect. Aldosterone stimulated H(+)-ATPase activity in isolated mouse and human OMCDs. This effect was blocked by suramin, a general G protein inhibitor, and GP-2A, a specific G(αq) inhibitor, whereas pertussis toxin was without effect. Inhibition of phospholipase C with U-73122, chelation of intracellular Ca(2+) with BAPTA, and blockade of protein kinase C prevented the stimulation of H(+)-ATPases. Stimulation of PKC by DOG mimicked the effect of aldosterone on H(+)-ATPase activity. Similarly, aldosterone and DOG induced a rapid translocation of H(+)-ATPases to the luminal side of OMCD cells in vivo. In addition, PD098059, an inhibitor of ERK1/2 activation, blocked the aldosterone and DOG effects. Inhibition of PKA with H89 or KT2750 prevented and incubation with 8-bromoadenosine-cAMP mildly increased H(+)-ATPase activity. Thus, the nongenomic modulation of H(+)-ATPase activity in OMCD-intercalated cells by aldosterone involves several intracellular pathways and may be mediated by a G(αq) protein-coupled receptor and PKC. PKA and cAMP appear to have a modulatory effect. The rapid nongenomic action of aldosterone may participate in the regulation of H(+)-ATPase activity and contribute to final urinary acidification.