Common polymorphisms in the P-selectin gene in women with recurrent spontaneous abortions

Background

To investigate possible associations of P-selectin polymorphisms with idiopathic recurrent pregnancy loss (RPL).

Methods

Study subjects comprised 270 consecutive RPL cases attending outpatient maternity services, and 322 multi-parous control women. P-selectin genotyping was done by PCR-RFLP and PCR-ASA methods.

Results

The P-selectin variants rs1800807, rs1800805, and rs6127, were in Hardy Weinberg equilibrium, and low linkage disequilibrium was noted between the three studied SNPs. The frequency of rs6127 A allele (P < 0.001I), but not rs1800807 C allele (P = 0.957) or rs1800805 A allele (P = 0.760), was higher in RPL cases than in control women. Significant differences in the distribution of rs6127 (P < 0.001), but not rs1800807 (P = 0.444) or rs1800805 (P = 0.391) genotypes were seen between cases and controls, and only rs6127 showed a significant association with RPL, with increments of 2.65 and 4.96 in disease risk seen for heterozygous and homozygous carriers, respectively. Among the 8 three-locus Pselectin haplotypes constructed (rs1800807/rs1800805/rs6127), increased frequency of GGG (Pc = 0.0249), CGG (Pc = 0.0256), and CAG (Pc = 0.0174) haplotypes, and lower frequency of CGA haplotype (Pc = 0.0091) were seen in RPL cases, thus conferring disease susceptibility and protective nature to these haplotypes, respectively.

Conclusions

P-selectin gene polymorphisms and haplotypes contribute to RPL development.     

Analyzing the responses of saccharin in context with melatonin receptors on the melanophores of the fish Labeo rohita (Ham.)

The hormone melatonin regulates the biological clock and assist in various other physiologies of vertebrates. Present work is intended to check the affinity of saccharin towards the melatonin receptors and the possible role of saccharin interference in the melatonin physiology. The present in vitro study is based on the working model of isolated scale melanophores in the dorso-lateral region of Labeo rohita. The pigment cells were incubated in the agonist and the antagonists within a limited time frame and subsequently their Melanophore Size Index (MSI) were calculated. The inferences were drafted through the observed signal transduction upshots in pigment translocations within the melanophores. Saccharin, in a wide dose range, has consistently induced a concentration-related aggregation similar to the aggregatory effect as shown by melatonin on the melanophores. Binding of saccharin with the receptors and eliciting its aggregatory effect is partially dependent on the release of neurotransmitters. The aggregatory effects were found to be significantly blocked by luzindole, K185, and prazosin, which are the potent melatonin receptor blockers, at the higher concentrations of saccharin. Hence, all the three subtypes of melatonin receptors viz. MT?, MT?, and MT? are participating in saccharin-mediated aggregations. Blocking by neomycin shows that Ca2? ions are very crucial in dispensing the aggregatory effect of the sweetener. This research demands that an intensive and careful thorough study should be made about saccharin, specifically its effects upon melatonin physiology, before its unwarranted use as the food ingredients for human use.     

Synthesis, characterization and antifungal activity of a series of manganese(II) and copper(II) complexes with ligands derived from reduced N,N'-O-phenylenebis(salicylideneimine)

A series of manganese(II) and copper(II) complexes with reduced Schiff bases derived from o-phenylenediamine has been prepared and characterized by elemental analysis, TG measurements, ESR, magnetic measurements, FTIR, UV-Visible spectra and conductivity. These complexes were found to be [MnL(H2O)n] and [CuL](H2O)n species with n=0-2. Their antifungal activity was evaluated on different human fungi including yeasts of the Candida genus (C. albicans, C. glabrata, C. tropicalis and C. parapsilopsis) some opportunistic moulds belonging to the Aspergillus (A. fumigatus, A. terreus and A. flavus), Scedosporium genus (S. apiospermum and S. prolificans) and some dermatophytes (M. gypseum, M. persicolor, T. mentagrophytes, M. canis and T. tonsurans). The manganese complexes showed a significant growth inhibition of the dermatophytes tested and fungi of the genus Scedosporium. This is very interesting as these fungi are usually poorly susceptible to current antifungal including Amphotericin B and Itraconazole chosen as reference in this study.     

Characterization of a unique sigma54-dependent PTS operon of the lactose family in Listeria monocytogenes

The sigma(54) subunit of the RNA polymerase directs the expression of specific operons in association with cognate activators. Three different activators have been detected in the Listeria monocytogenes genome on the basis of the high conservation of a specific domain. Among them, the LacR activator, of the LevR family, was found just upstream from a newly described sigma(54)-dependent operon, lpo, which presents a classical -24/-12 consensus promoter. The lpo operon encodes proteins similar to subunits of a PTS permease (EII) of the lactose family, namely LpoA (IIA) and LpoB (IIB). It also encodes a third putative protein, LpoO, with an unknown function but sharing high similarity with proteins also encoded within PTS operons from other bacteria and bearing a RGD motif. The expression of lpo was clearly dependent on LacR and sigma(54), and was induced by cellobiose, chitobiose and lactose. It underlies that the lpo operon likely encodes proteins involved in the utilization of these sugars by L. monocytogenes.     

On possible trypsin-induced biases in peptides analysis with aerolysin nanopore

Nanopore-based single-molecule analysis technique is a promising approach in the field of proteomics. In this Technical Brief, the interaction between the biological nanopore of Aerolysin (AeL) and peptides is investigated, focusing on potential biases depending on the AeL activation protocol. Our results reveal that residual trypsin, which may be unintentionally introduced in analyte solution when using a classical AeL activation protocol, can induce a significant formation of shorter peptides by enzymatic degradation of longer ones, which may lead to unwanted effects and/or misinterpretations. AeL free-trypsin activation protocol eliminates this bias and appears more appropriate for peptide/proteins analysis, specifically in the perspective of nanopore-based molecular fingerprinting or of low-abundance species characterization.     

Intact female stroke-prone hypertensive rats lack responsiveness to mineralocorticoid receptor antagonists

Data from the Framingham Heart Study suggest that women may be more sensitive to the deleterious cardiovascular remodeling effects of aldosterone. Previous studies from our laboratory have shown that chronic treatment with spironolactone, a mineralocorticoid receptor (MR) antagonist, decreases ischemic cerebral infarct size and prevents remodeling of the middle cerebral artery (MCA) in male spontaneously hypertensive stroke-prone rats (SHRSP). Therefore, we hypothesized that MR antagonism would reduce ischemic infarct size and prevent MCA remodeling in female SHRSP. Six-week-old female SHRSP were treated for 6 wk with spironolactone (25 or 50 mg.kg(-1).day(-1)) or eplerenone (100 mg.kg(-1).day(-1)) and compared with untreated controls. At 12 wk, cerebral ischemia was induced for 18 h using the intraluminal suture occlusion technique, or the MCA was isolated for analysis of passive structure using a pressurized arteriograph. MR antagonism had no effect on infarct size or passive MCA structure in female SHRSP. To study the potential effects of estrogen, the above experiments were repeated in bilaterally ovariectomized (OVX) female SHRSP treated with spironolactone (25 mg.kg(-1).day(-1)). Infarct size and vessel structure in OVX SHRSP were not different from control SHRSP. Spironolactone had no effect on infarct size in OVX SHRSP. However, MCA lumen and outer diameters were increased in spironolactone-treated OVX SHRSP, suggesting an effect of estrogen. Cerebral artery MR expression, assessed by Western blotting, was increased in female, compared with male, SHRSP. These studies highlight an apparent sexual dimorphism of MR expression and activity in the cerebral vasculature from hypertensive rats.     

Population diversity of sheep bot fly,Oestrus ovis (Linné, 1758) (Diptera: Oestridae: Oestrinae), using SDS polyacrylamide gel electrophoresis

The study was planned to evaluate the inter, and intra population genetic variation in general protein banding pattern in Oestrus ovis larvae, by using 10% sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS PAGE). The larvae were collected from slaughtered goats head from five different locations (AAS, PN, LA, GM, and BC) of Karachi, Pakistan. The data obtained was subjected to POPGENE (Population Genetic Analysis) software for analysis. The polymorphic loci within populations ranged from 45.45% to 90.91%. Polymorphic loci observed in all populations were 90.91%. The expected heterozygosity observed was 0.182 ± 0.096 in all populations. The chi-square test showed 5 out of 11 loci at H-W equilibrium. The overall fixation index (FST) value was 0.108, showing that the likelihood of subpopulations being differentiated from one another is about 11 percent. The gene flow value (Nm = 2.065) was higher, showing that genes flow occurs between populations. The values of genetic identity were greater, and genetic distance were smaller among all the populations, which means that all the populations were more alike and closer to each other. It was concluded that there was no sympatric and parapatric population differentiation observed among all the population of O. ovis and the populations of the five different locations were not genetically and reproductively isolated from each other.     

Activation of the JAK/STAT pathway in vascular smooth muscle by serotonin

Serotonin (5-hydroxytryptamine, 5-HT) is a vasoconstrictor and mitogen whose levels are elevated in diabetes. Previous studies have shown the presence of 5-HT_2A, 5-HT_2B, and 5-HT_1B receptors in vascular smooth muscle cells (VSMCs). There are currently no data regarding 5-HT_2B and 5-HT_1B receptor activation of the JAK/STAT pathway in VSMCs and resultant potential alterations in 5-HT signaling in diabetes. Therefore, we tested the hypothesis that 5-HT differentially activates the JAK/STAT pathway in VSMCs under conditions of normal (5 mM) and high (25 mM) glucose. Treatment of rat VSMCs with 5-HT (10^–6 M) resulted in time-dependent activation (2-fold) of JAK2, JAK1, and STAT1, but not STAT3 (maximal at 5 min, returned to baseline by 30 min). The 5-HT_2B receptor agonist BW723C86 and the 5-HT_1B receptor agonist CGS12066A (10^–9–10^–5 M, 5-min stimulation) did not activate the JAK/STAT pathway. Treatment with the 5-HT_2A receptor antagonist ketanserin (10 nM) inhibited JAK2 activation by 5-HT. Treatment of streptozotocin-induced diabetic rats with ketanserin (5 mg·kg^–1·day^–1) reduced activation of JAK2 and STAT1 but not STAT3 in endothelium-denuded thoracic aorta in vivo. 5-HT (10^–6 M) treatment resulted in increased cell proliferation and increased DNA synthesis, which were inhibited by the JAK2 inhibitor AG490. Further studies with apocynin, diphenyleneiodonium chloride, catalase, and virally transfected superoxide dismutase had no effect at either glucose concentration on activation of the JAK/STAT pathway by 5-HT. Therefore, we conclude that 5-HT activates JAK2, JAK1, and STAT1 via the 5-HT_2A receptors in a reactive oxygen species-independent manner under both normal and high glucose conditions. reactive oxygen species; 5-hydroxytryptamine     

Induction of non-lamellar lipid phases by antimicrobial peptides: a potential link to mode of action

Antimicrobial peptides are naturally produced by numerous organisms including insects, plants and mammals. Their non-specific mode of action is thought to involve the transient perturbation of bacterial membranes but the molecular mechanism underlying the rearrangement of the lipid molecules to explain the formation of pores and micelles is still poorly understood. Biological membranes mostly adopt planar lipid bilayers; however, antimicrobial peptides have been shown to induce non-lamellar lipid phases which may be intimately linked to their proposed mechanisms of action. This paper reviews antimicrobial peptides that alter lipid phase behavior in three ways: peptides that induce positive membrane curvature, peptides that induce negative membrane curvature and peptides that induce cubic lipid phases. Such structures can coexist with the bilayer structure, thus giving rise to lipid polymorphism induced upon addition of antimicrobial peptides. The discussion addresses the implications of induced lipid phases for the mode of action of various antimicrobial peptides.     

Decolorization of structurally different textile dyes by Aspergillus niger SA1

The fungal strain, Aspergillus niger SA1, isolated from textile wastewater sludge was screened for its decolorization ability for four different textile dyes. It was initially adapted to higher concentration of dyes (10–1,000 mg l⁻¹) on solid culture medium after repeated sub-culturing. Maximum resistant level (mg l⁻¹) sustained by fungal strain against four dyes was in order of; Acid red 151 (850) > Orange II (650) > Drimarene blue K₂RL (550) > Sulfur black (500). The apparent dye removal for dyes was seen largely due to biosorption/bioadsorption into/onto the fungal biomass. Decolorization of Acid red 151, Orange II, Sulfur black and Drimarine blue K₂RL was 68.64 and 66.72, 43.23 and 44.52, 21.74 and 28.18, 39.45 and 9.33% in two different liquid media under static condition, whereas, it was 67.26, 78.08, 45.83 and 13.74% with 1.40, 1.73, 5.16 and 1.87 mg l⁻¹ of biomass production under shaking conditions respectively in 8 days. The residual amount (mg l⁻¹) of the three products (α-naphthol, sulfanilic acid and aniline) kept quite low i.e., ≤2 in case AR 151 and Or II under shaking conditions. Results clearly elucidated the role of Aspergillus niger SA1 in decolorizing/degrading structurally different dyes into basic constituents.