Synergistic effects of antiprogestins and iNOS or aromatase inhibitors on establishment and maintenance of pregnancy

Progesterone is known to be involved in many steps in female reproduction including control of implantation and uterine-cervical function during pregnancy. Our studies in rats and guinea pigs indicate that progesterone inhibits uterine contractility and cervical softening during pregnancy. Progesterone levels or actions decline near the end of pregnancy leading to the onset of labor. Treatment with progestin agonists prolongs pregnancy and inhibits cervical softening, whereas treatment with antiprogestins (mifepristone or onapristone) stimulates uterine contractility, cervical softening and premature delivery. Thus the effect of progesterone receptor modulators in the uterus and cervix depend up on the degree of intrinsic agonistic/antagonistic activities. Our recent studies show that progesterone interacts with nitric oxide (NO) to maintain pregnancy and that administration of progesterone antagonists with NO synthase inhibitors act synergistically to stimulate labor. In addition our studies show that combinations of progesterone antagonists with aromatase inhibitors act synergistically to induce labor. Similarly antiprogestins interact with NO synthase or aromatase inhibitors to block implantation through action on the endometrium. These studies suggest new applications for combined therapies of progestin receptor modulators with aromatase inhibitors or agents that modify NO production for contraception, stimulation of labor, estrogen-dependent diseases and improved outcomes in pregnancy.     

Superantigenic Activity of emm3 Streptococcus pyogenes Is Abrogated by a Conserved, Naturally Occurring smeZ Mutation

Streptococcus pyogenes M/emm3 strains have been epidemiologically linked with enhanced infection severity and risk of streptococcal toxic shock syndrome (STSS), a syndrome triggered by superantigenic stimulation of T cells. Comparison of S. pyogenes strains causing STSS demonstrated that emm3 strains were surprisingly less mitogenic than other emm-types (emm1, emm12, emm18, emm28, emm87, emm89) both in vitro and in vivo, indicating poor superantigenic activity. We identified a 13 bp deletion in the superantigen smeZ gene of all emm3 strains tested. The deletion led to a premature stop codon in smeZ, and was not present in other major emm-types tested. Expression of a functional non-M3-smeZ gene successfully enhanced mitogenic activity in emm3 S. pyogenes and also restored mitogenic activity to emm1 and emm89 S. pyogenes strains where the smeZ gene had been disrupted. In contrast, the M3-smeZ gene with the 13 bp deletion could not enhance or restore mitogenicity in any of these S. pyogenes strains, confirming that M3-smeZ is non-functional regardless of strain background. The mutation in M3-smeZ reduced the potential for M3 S. pyogenes to induce cytokines in human tonsil, but not during invasive infection of superantigen-sensitive mice. Notwithstanding epidemiological associations with STSS and disease severity, emm3 strains have inherently poor superantigenicity that is explained by a conserved mutation in smeZ.     

Fusaric acid induces apoptosis in saffron root-tip cells: roles of caspase-like activity, cytochrome c, and H2O2

Programmed cell death (PCD), now known as apoptosis, is accompanied by specific morphological features. In this study, fusaric acid, a fusarium mycotoxin, was used to examine cell death in saffron (Crocus sativus Linnaeus) roots, using several apoptosis assays. Our results show that moderate FA doses (50–100 μM) induce apoptotic features while high FA doses (> 200 μM) stimulate necrosis. The apoptotic-like features induced by moderate doses of FA include chromatin condensation, formation of condensed chromatin spheres which bud from the nucleus, fragmentation of nucleosomal DNA into ∼ 180 bp fragments, exposure of phosphatidyl serine to the external membrane leaflet, delivery of cytochrome c to cytosol, and generation of H₂O₂. These apoptotic alterations in root cells are not observed in the presence of serine protease, caspase-1 or caspase-3 inhibitors. It is proposed that production of H₂O₂ and release of cytochrome c into the cytosol may activate caspase-like proteases and thus establish the apoptotic pathway. As nuclei budding spheres formed in plant root cells after exposure to 50–100 μM FA doses seem to be digested inside the cytosol, we suggest labeling them as internal apoptotic bodies (IAB) that may be more informative than previously used term, apoptotic-like bodies.Electronic Supplementary Material Supplementary material is available to authorised users in the online version of this article at .     

Antimicrobial Resistance and Molecular Investigation of H2S-Negative Salmonella enterica subsp. enterica serovar Choleraesuis Isolates in China

Salmonella enterica subsp. enterica serovar Choleraesuis is a highly invasive pathogen of swine that frequently causes serious outbreaks, in particular in Asia, and can also cause severe invasive disease in humans. In this study, 21 S. Choleraesuis isolates, detected from 21 patients with diarrhea in China between 2010 and 2011, were found to include 19 H₂S-negative S. Choleraesuis isolates and two H₂S-positive isolates. This is the first report of H₂S-negative S. Choleraesuis isolated from humans. The majority of H₂S-negative isolates exhibited high resistance to ampicillin, chloramphenicol, gentamicin, tetracycline, ticarcillin, and trimethoprim-sulfamethoxazole, but only six isolates were resistant to norfloxacin. In contrast, all of the isolates were sensitive to cephalosporins. Fifteen isolates were found to be multidrug resistant. In norfloxacin-resistant isolates, we detected mutations in the gyrA and parC genes and identified two new mutations in the parC gene. Pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), and clustered regularly interspaced short palindromic repeat (CRISPR) analysis were employed to investigate the genetic relatedness of H₂S-negative and H₂S-positive S. Choleraesuis isolates. PFGE revealed two groups, with all 19 H₂S-negative S. Choleraesuis isolates belonging to Group I and H₂S-positive isolates belonging to Group II. By MLST analysis, the H₂S-negative isolates were all found to belong to ST68 and H₂S-positive isolates belong to ST145. By CRISPR analysis, no significant differences in CRISPR 1 were detected; however, one H₂S-negative isolate was found to contain three new spacers in CRISPR 2. All 19 H₂S-negative isolates also possessed a frame-shift mutation at position 760 of phsA gene compared with H₂S-positive isolates, which may be responsible for the H₂S-negative phenotype. Moreover, the 19 H₂S-negative isolates have similar PFGE patterns and same mutation site in the phsA gene, these results indicated that these H₂S-negative isolates may have been prevalent in China. These findings suggested that surveillance should be increased of H₂S-negative S. Choleraesuis in China.     

Prospect of mesenchymal stem cells in therapy of osteoporosis: A review

Osteoporosis is a systemic skeletal disease associated with reduced bone strong point that results in raised fracture risk, with decreased bone strength, leading to reduced bone mineral density and poor bone quality. It is the most common in older females but some men are also at high risk. Although considered as a predictable result of aging, it is can be avoidable and treatable. The existing treatment of osteoporosis mainly contains antiresorptive and anabolic agents. In spite of these improvements, concerns around unusual side-effects of antiresorptive drugs, and the lack of perfect confirmation in maintenance of their long-standing effectiveness is bring about many patients not receiving these drugs. Over the years, the stem cell-based therapy has attained substantial clinical consideration because of its potential to treat numerous diseases. The stem cell therapy has been recommended as a probable therapeutic approach for patients with osteoporosis. Even though the concept of stem cell-based therapy for osteoporosis has caught substantial attention, no clinical trial has been published on humans. The cell studies based on osteoporosis are primarily focused on osteoclastic activity and bone resorption procedures. Earlier, it was on osteoblastogenesis and in recent times, on the differentiation probable of mesenchymal stem cells. In this review, we have summarized the therapeutic role of stem cell-based strategy in osteoporosis.     

Holocene vegetation and land-use history in the environs of Lake Kahala, northern Estonia

Pollen profiles, based cores taken in Lake Kahala and from the adjoining mire, were used to establish general vegetation history and to reconstruct the extent and types of land-use over most of the Holocene. Modern pollen deposition was studied using moss polsters and the results were used in the interpretation of the fossil pollen data in terms of former land-use practices. The modern-day samples are from settlements, hay meadow and pasture, and overgrown pasture. Indications of human activity can be traced back to the Stone Age. At ca. 6400 cal. B.C., the first indications of possible woodland utilisation by humans are recorded. This may have involved grazing within the forests. From 4200 cal. B.C. onwards, animal husbandry with changing intensity was practised. Arable farming, involving cereals, was introduced to the area at ca. 1800 cal. B.C., but it was only at ca. 500 cal. B.C. that it assumed an important role in the farming economy.Secale cereale (rye) was introduced during the Roman Iron Age, intensive rye cultivation started at the end of the Iron Age, at ca. cal. A.D. 800. Ever increasing farming pressures triggered the formation of openalvars. Open landscape similar to that of today has persisted, with minor forest regeneration phases, since at least 500 cal. B.C.     

Tethered Spectroscopic Probes Estimate Dynamic Distances with Subnanometer Resolution in Voltage-Dependent Potassium Channels

Measurements of inter- and intramolecular distances are important for monitoring structural changes and understanding protein interaction networks. Fluorescence resonance energy transfer and functionalized chemical spacers are the two predominantly used strategies to map short-range distances in living cells. Here, we describe the development of a hybrid approach that combines the key advantages of spectroscopic and chemical methods to estimate dynamic distance information from labeled proteins. Bifunctional spectroscopic probes were designed to make use of adaptable-anchor and length-varied spacers to estimate molecular distances by exploiting short-range collisional electron transfer. The spacers were calibrated using labeled polyproline peptides of defined lengths and validated by molecular simulations. This approach was extended to estimate distance restraints that enable us to evaluate the resting-state model of the Shaker potassium channel.