Identification of vibriocidal compounds from medicinal plants using chromatographic fingerprinting

The aim of the present study was to investigate the vibriocidal activity of bark of Syzygium cumini, leaves of Lawsonia inermis, fruits of Terminalia bellerica and identify the bioactive compounds. The vibriocidal activity of plant extracts was determined in aqueous and organic solvents, and the minimum inhibitory concentration (MIC) against Vibrio spp. using the disk diffusion method was established. The chemical constituents of the plant extracts were analysed by thin layer chromatography (TLC), the vibriocidal compounds were determined by TLC-bioautography and were further confirmed by high performance liquid chromatography (HPLC). Significant inhibitory activity was observed with ethanol extract of plants against the test bacteria while less antibacterial activity was observed in acetone, methanol and aqueous extracts. The MIC of the plant extracts ranged between 2.5 and 20 mg/ml. The TLC, TLC-bioautography and HPLC analysis showed that gallic acid and tannin present in ethanol extracts of S. cumini, tannin present in L. inermis and gallic acid present in T. bellerica may be responsible for the vibriocidal activity. S. cumini, L. inermis and T. bellerica can be used for the treatment of gastroenteritis, diarrhoea and cholera diseases after detailed investigations. We also conclude that the plants rich in gallic acid and tannin can be used as an alternative to search for new vibriocidal drugs.     

Increased cardiogenesis in P19-GFP teratocarcinoma cells expressing the propeptide IGF-1Ea

The mechanism implicated in differentiation of endogenous cardiac stem cells into cardiomyocytes to regenerate the heart tissue upon an insult remains elusive, limiting the therapeutical goals to exogenous cell injection and/or gene therapy. We have shown previously that cardiac specific overexpression of the insulin-like growth factor 1 propeptide IGF-1Ea induces beneficial myocardial repair after infarct. Although the mechanism is still under investigation, the possibility that this propeptide may be involved in promoting stem cell differentiation into the cardiac lineage has yet to be explored. To investigate whether IGF-1Ea promote cardiogenesis, we initially modified P19 embryonal carcinoma cells to express IGF-1Ea. Taking advantage of their cardiomyogenic nature, we analyzed whether overexpression of this propeptide affected cardiac differentiation program. The data herein presented showed for the first time that constitutively overexpressed IGF-1Ea increased cardiogenic differentiation program in both undifferentiated and DMSO-differentiated cells. In details, IGF-1Ea overexpression promoted localization of alpha-actinin in finely organized sarcomeric structure compared to control cells and upregulated the cardiac mesodermal marker NKX-2.5 and the ventricular structural protein MLC2v. Furthermore, activated IGF-1 signaling promoted cardiac mesodermal induction in undifferentiated cells independently of cell proliferation. This analysis suggests that IGF-1Ea may be a good candidate to improve both in vitro production of cardiomyocytes from pluripotent stem cells and in vivo activation of the differentiation program of cardiac progenitor cells.     

Importance of Cough and M. tuberculosis Strain Type as Risks for Increased Transmission within Households

Rationale

The degree to which tuberculosis (TB) is transmitted between persons is variable. Identifying the factors that contribute to transmission could provide new opportunities for TB control. Transmission is influenced by host, bacterial and environmental factors. However, distinguishing their individual effects is problematic because measures of disease severity are tightly correlated, and assessing the virulence of Mycobacterium tuberculosis isolates is complicated by epidemiological and clinical confounders.

Objectives

To overcome these problems, we investigated factors potentially associated with TB transmission within households.

Methods

We evaluated patients with smear-positive (≥2+), pulmonary TB and classified M. tuberculosis strains into single nucleotide polymorphism genetic cluster groups (SCG). We recorded index case, household contact, and environmental characteristics and tested contacts with tuberculin skin test (TST) and interferon-gamma release assay. Households were classified as high (≥70% of contacts with TST≥10 mm) and low (≤40%) transmission. We used logistic regression to determine independent predictors.

Result

From March 2008 to June 2012, we screened 293 TB patients to enroll 124 index cases and their 731 contacts. There were 23 low and 73 high transmission households. Index case factors associated with high transmission were severity of cough as measured by a visual analog cough scale (VACS) and the Leicester Cough Questionnaire (LCQ), and cavitation on chest radiograph. SCG 3b strains tended to be more prevalent in low (27.3%) than in high (12.5%) transmission households (p = 0.11). In adjusted models, only VACS (p<0.001) remained significant. SCG was associated with bilateral disease on chest radiograph (p = 0.002) and marginally associated with LCQ sores (p = 0.058), with group 3b patients having weaker cough.

Conclusions

We found differential transmission among otherwise clinically similar patients with advanced TB disease. We propose that distinct strains may cause differing patterns of cough strength and cavitation in the host leading to diverging infectiousness. Larger studies are needed to verify this hypothesis.     

HSP70 expression and its role in preeclamptic stress

Preeclampsia, a hypertensive pregnancy-specific disorder, has long been analyzed for its association with cellular stress. It still remains one of the most serious complications of pregnancy. It is a multi-system disorder that affects maternal vascular function and fetal growth. The physiopathology of preeclampsia is still unclear, but an imbalance between reactive oxygen species (ROS) and antioxidants, appears to be an important contributing factor. Oxidative stress has been increasingly postulated as a major contributor to endothelial dysfunction in preeclampsia (PE). The ROS promotes lipid oxidation and are known to induce stress proteins, such as hemeoxygenase 1 (HO-1) and heat-shock protein 70 (HSP70). Embryonic and placental cells are highly sensitive to oxidative stress due to their proliferate nature. Endothelial cell dysfunction is suggested to be a part of wider maternal inflammatory reaction responsible for the clinical syndrome of preeclampsia. Part of the dysfunction in endothelial cell and trophoblast is attributed to oxidative stress developed during pregnancy. The disequilibrium in compensatory antioxidant control is proposed as a causative mechanism in the pathophysiology of preeclampsia. HSP70 acts as the secondary line of defense in systems with compromised antioxidant function. This article reviews the differential expression of HSP70 and the effect of mint-tea therapy to modulate preeclamptic oxidative damage.     

Synthesis of silver nanoparticles by Bacillus clausii and computational profiling of nitrate reductase enzyme involved in production

Biogenic synthesis of silver nanoparticles using microorganisms has found interest recently since last decade because of their prospect to synthesize nanoparticles of various size, shape and morphology which are eco-friendly. Here, an eco-friendly method for production of silver nanoparticles from Bacillus clausii cultured from Enterogermina is explored. Along with the biosynthesis and conformity test, in silico studies was done on NADPH dependent nitrate reductase enzymes from the view point of designing a rational enzymatic strategy for the synthesis. The detailed characterization of the nanoparticles was carried out using UV-Vis spectroscopy, Dynamic Light Scattering (DLS) particle size analysis, Transmission Electron Microscopy (TEM), X-Ray Diffraction (XRD) analysis. Computational profiling and in silico characterization of NADH dependent enzymes was carried out based on literature and work done so far. Nitrate reductase sequence was retrieved from NCBI for characterization. Secondary structure was evaluated and verified by JPred as well as SOPMA Tool. Tertiary structure was also modeled by MODELLER and ITASSER parallel and the best structure was selected based on energy values. Structure validation was done by GROMACS and RMSD, RMSF, temperature variation plot were also plotted. Interactions graphs between nitrate reductase and ligand silver nitrate was done through molecular docking using Hex.     

Media-induced changes in the asymbiotic nitrogen-fixing bacteroids ofBradyrhizobium sp. 32H1

Arabinose- and succinate-enriched media induced asymbiotic nitrogenase activity inBradyrhizobium sp. 32H1. When supplemented by arabinose alone, the bacteroids became elongated, forming rosette configurations, accompanied by reduced extracellular polysaccharide production. Enrichment with succinate, in addition to arabinose, induced swelling of bacteroids. The protein profile of the outer membrane showed marked absence of several high molecular weight polypeptides in the succinate-swollen bacteroids.     

ATR signaling mediates an S-phase checkpoint after inhibition of poly(ADP-ribose) polymerase activity

Human fibroblasts, capable of expressing a kinase-dead form of ATR (ATRkd), can be sensitized to the cytotoxic effects of methyl methanesulfonate (MMS) by the PARP inhibitor 4-amino-1,8-naphthalimide (4-AN). The combination of MMS+4-AN results in accumulation of cells in S-phase of the cell cycle and activation of Chk1. Inhibition of ATR activity by expression of ATRkd suppresses the S-phase accumulation and partially reverses the Chk1 phosphorylation. The results confirm involvement of an ATR-mediated damage response pathway in the MMS+4-AN-induced S-phase cell cycle checkpoint in human fibroblasts. Consistent with this hypothesis, the inhibitors caffeine and UCN-01 also abrogate the ATR- and Chk1-mediated delay in progression through S-phase. In the absence of ATR-mediated signaling, MMS+4-AN exposure results in a G(2)/M arrest, rather than an S-phase checkpoint. Thus, whereas ATR mediates the S-phase response, it is not critical for arrest of cells in G(2)/M.     

HMGN1 Protein Regulates Poly(ADP-ribose) Polymerase-1 (PARP-1) Self-PARylation in Mouse Fibroblasts

In mammalian cells, the nucleosome-binding protein HMGN1 (high mobility group N1) affects the structure and function of chromatin and plays a role in repair of damaged DNA. HMGN1 affects the interaction of DNA repair factors with chromatin and their access to damaged DNA; however, not all of the repair factors affected have been identified. Here, we report that HMGN1 affects the self-poly(ADP-ribosyl)ation (i.e., PARylation) of poly(ADP-ribose) polymerase-1 (PARP-1), a multifunctional and abundant nuclear enzyme known to recognize DNA lesions and promote chromatin remodeling, DNA repair, and other nucleic acid transactions. The catalytic activity of PARP-1 is activated by DNA with a strand break, and this results in self-PARylation and PARylation of other chromatin proteins. Using cells obtained from Hmgn1(-/-) and Hmgn1(+/+) littermate mice, we find that in untreated cells, loss of HMGN1 protein reduces PARP-1 self-PARylation. A similar result was obtained after MMS treatment of these cells. In imaging experiments after low energy laser-induced DNA damage, less PARylation at lesion sites was observed in Hmgn1(-/-) than in Hmgn1(+/+) cells. The HMGN1 regulation of PARP-1 activity could be mediated by direct protein-protein interaction as HMGN1 and PARP-1 were found to interact in binding assays. Purified HMGN1 was able to stimulate self-PARylation of purified PARP-1, and in experiments with cell extracts, self-PARylation was greater in Hmgn1(+/+) than in Hmgn1(-/-) extract. The results suggest a regulatory role for HMGN1 in PARP-1 activation.     

Protective effect of vilva juice on glycoconjugate levels in experimentally induced constipation in rats

Efficacy of vilva, a polyherbal formulation was evaluated in morphine induced constipated rats. Vilva juice, at a dose of 1.5 ml/100 g body wt was given orally for a period of 7 days. Morphine sulfate was injected to induce constipation on 8th day, 45 min before the experiments. Protein bound glycoconjungates were estimated in intestinal tissue. Altered levels of glycoconjugates were maintained at near normalcy when pretreated with vilva juice in morphine induced rats. Histological changes were observed in the colon tissue. The damage to crypts of Liberkunn in constipated rats were found to be reduced in vilva pretreated rats. Vilva, thus, offered significant protection against morphine induced constipation by way of augmenting mucus secretion.     

Diet of juvenile cod (age 0–2) in the Barents Sea in relation to food availability and cod growth

Diet investigations were carried out on 0-, 1- and 2-year-old Northeast Arctic cod (Gadus morhua) sampled in the Barents Sea during 1984–2002. Stomach-content analyses showed that the 0 and 1 group cod fed mainly on crustaceans, with krill and amphipods composing up to 70% of their diet. Krill (Thysanoessa spp. and Meganyctiphanes norvegica) and amphipods (Themisto spp.) were mainly found in cod stomachs sampled in the central and close to the Polar Front region in the Barents Sea where these prey organisms are reported to be abundant in summer. A shift in the main diet from crustaceans to fish was observed from age 1 to age 2. The diet of 2-year-old cod mainly comprised capelin (Mallotus villosus) and other fish, and to a lesser degree, krill and amphipods. Shrimp (mainly Pandalus spp.) was also an important prey in both age 1 and 2 cod. A statistically significant positive relationship was obtained between capelin stock size and the amount of capelin in the diet of 2-year-old cod. Results from this study also show that the larger age-2 cod preyed more on capelin in winter and that larger cod (>22 cm) prefer larger capelin (>12 cm). During periods of low capelin abundance, the 2-year-old cod shift their diet more to crustaceans, such as krill and amphipods. A positive significant relationship was also obtained between Total Fullness Index (TFI) and the amount of capelin in the diet and between TFI and the growth of 2-year-old cod, indicating that the growth of age-2 cod is to a large extent dependent on the amount of capelin consumed. Growth of age-1 cod was also positively correlated to TFI.