In vitro Antioxidant and Antibacterial Activities of Methanol Extract of Kyllinga nemoralis

The present study was designed to evaluate the antioxidant and antibacterial activity of methanol extract of Kyllinga nemoralis. Six different in vitro antioxidant assays including 2,2-diphenyl-1-picrylhydrazyl, hydroxyl radical, superoxide anion radical, hydrogen peroxide radical, ferric reducing antioxidant power assay and reducing power were carried out to ensure the scavenging effect of the plant on free radicals. In addition, total antioxidant capacity assay, total phenolic contents, tannins, flavonoids and flavonol contents of the plant were also analysed by the standard protocols. Kyllinga nemoralis exhibited high antioxidant activity on 2,2-diphenyl-1-picrylhydrazyl assay (IC₅₀= 90 μg/ml), superoxide radical scavenging assay (IC₅₀= 180 μg/ml) and hydrogen peroxide radical scavenging assay (IC₅₀= 200 μg/ml), compared with standards. These observations provide comprehensible supporting evidence for the antioxidant potential of the plant extract. Reducing power (IC₅₀= 213.16 μg/ml) and hydroxyl radical scavenging activity (IC₅₀= 223 μg/ml) of the plant extract was remarkable. The methanol extract of K. nemoralis exhibited significant antimicrobial activity against Gram-positive human pathogenic bacteria. Standard in vitro antioxidant assays assessed the electron donating ability of the plant extract in scavenging free radicals. The inhibitory effect of the plant extract against bacterial pathogens may be due to the presence of phytochemicals. Thus, the results suggest that Kyllinga nemoralis is a potential source of antioxidants and could serve as the base for drug development.     

From the Cover: PACAP is a pathogen-inducible resident antimicrobial neuropeptide affording rapid and contextual molecular host defense of the brain

Defense of the central nervous system (CNS) against infection must be accomplished without generation of potentially injurious immune cell-mediated or off-target inflammation which could impair key functions. As the CNS is an immune-privileged compartment, inducible innate defense mechanisms endogenous to the CNS likely play an essential role in this regard. Pituitary adenylate cyclase-activating polypeptide (PACAP) is a neuropeptide known to regulate neurodevelopment, emotion, and certain stress responses. While PACAP is known to interact with the immune system, its significance in direct defense of brain or other tissues is not established. Here, we show that our machine-learning classifier can screen for immune activity in neuropeptides, and correctly identified PACAP as an antimicrobial neuropeptide in agreement with previous experimental work. Furthermore, synchrotron X-ray scattering, antimicrobial assays, and mechanistic fingerprinting provided precise insights into how PACAP exerts antimicrobial activities vs. pathogens via multiple and synergistic mechanisms, including dysregulation of membrane integrity and energetics and activation of cell death pathways. Importantly, resident PACAP is selectively induced up to 50-fold in the brain in mouse models of Staphylococcus aureus or Candida albicans infection in vivo, without inducing immune cell infiltration. We show differential PACAP induction even in various tissues outside the CNS, and how these observed patterns of induction are consistent with the antimicrobial efficacy of PACAP measured in conditions simulating specific physiologic contexts of those tissues. Phylogenetic analysis of PACAP revealed close conservation of predicted antimicrobial properties spanning primitive invertebrates to modern mammals. Together, these findings substantiate our hypothesis that PACAP is an ancient neuro-endocrine-immune effector that defends the CNS against infection while minimizing potentially injurious neuroinflammation.

Neuropeptides enable interneuronal communication and signaling (1), mediating diverse functions ranging from endocrine stimulation and homeostatic regulation to immune signaling, pain modulation, and circadian rhythm maintenance. At present, over 100 neuropeptides are known in mammals (2). These peptides originate from neurons in the central, enteric, or peripheral nervous systems and within immune organs (3). Canonically, neuropeptides exert their biological function by binding to a cognate receptor (usually a G-coupled protein receptor [GPCR]), triggering a signal transduction pathway that leads to a functional change in the target cell (1). Neuropeptides are typically considered neurotransmitters or neurohormones, but recent work has illuminated their potential roles in modulating immune responses and neuroinflammation (4–8).Human innate and adaptive immunity have evolved via two parallel and complementary paradigms in host defense against microbial invasion: molecular and cellular. Molecular defense mediators are secreted or activated rapidly and locally to directly inhibit pathogens. Prototypic examples include host-defense peptides (HDPs), the acute-phase reactants, and the complement cascade. Cellular defense involves infiltration of professional immune phagocytes (neutrophils and macrophages) and lymphocytes into infected tissues. Cellular infiltration into the central nervous system (CNS) is a double-edged sword, given its anatomically confined space and physiologically delicate context. On one hand cellular defense may be necessary to control or clear certain pathogens. On the other hand, neutrophils and other phagocytes can cause counterproductive damage to tissue parenchyma due to production and release of reactive oxygen species and other cytotoxic constituents from phagolysosomes. Thus, molecular defenses that are rapidly deployable in immediate settings of infection to obviate the need for infiltration of potentially harmful immune cells would be of special relevance in context of the CNS.To explore putative molecular host-defense mediators within the CNS that may have both neuro- and immunomodulatory properties, we used a support vector machine (SVM) trained on HDPs (9, 10) to identify neuropeptides with potential host defense capabilities. Among the human neuropeptides identified as potential HDPs for molecular host defense of the CNS is pituitary adenylate cyclase-activating polypeptide (PACAP). PACAP is a member of the vasoactive intestinal peptide (VIP)/PACAP/secretin family (11) that regulates neurodevelopment (12), metabolism, emotion, mood, and stress responses via GPCRs (13). PACAP is known to interact with the immune system (14, 15) and modulate T helper type 1 (TH1)/TH2 cytokine production (3). Important previous work on structure activity relationships (SAR) of PACAP have also shown that it possess antimicrobial activity in vitro against a range of organisms (16–18), as well as anti-cancer activity against tumor cell lines. (Interestingly, our use of an SVM classifier that can scan different fragments of the same peptide allows us to identify antimicrobial activity in previously identified metabolites of PACAP as well^* (19)). However, host defense functions, contextual bioactivity, or pathogen-specific inducibility of PACAP or other neuropeptides regarding antimicrobial activity in vivo are not known. More specifically, the role of PACAP in the larger context of innate immunity and its in vivo relevance to antimicrobial defense of the CNS and in other tissues remains unclear, given that antimicrobial activity is strongly dependent on biochemical and physiological context (20, 21, 22). Here, we examine PACAP inducibility in response to infection in the CNS and other tissues, and whether PACAP exerts antimicrobial activity against relevant organisms in the specific biochemical context relevant to those tissues. Bioinformatic and structural analyses showed PACAP to possess almost identical structural similarity to human cathelicidin LL-37, despite having overall low sequence similarity to other known HDPs. Synchrotron X-ray scattering revealed that PACAP can induce negative Gaussian curvature (NGC) in microbial membranes, a general requirement for membrane-permeating antimicrobial processes such as pore formation, blebbing, and other membrane-perturbing events (23–25). Moreover, extending from prior work (18), antimicrobial assays and mechanistic fingerprinting analyses showed that PACAP exerts potent antimicrobial mechanisms against drug-resistant bacteria and fungi via multiple synergistic pathways, including permeabilization, disruption of cellular energetics, and activation of regulated cell death pathways. In mouse models of bacterial or fungal infection, we demonstrated that PACAP is strongly induced up to 50-fold in brain, spleen, or kidney. Further, in media simulating these tissue contexts, PACAP exerted robust microbiostatic and microbicidal efficacy. Taken together, these findings imply that PACAP is an infection-inducible, tissue-specific host-defense effector that affords rapid and contextual antimicrobial host defense in the CNS and periphery. Beyond immediate contributions to better understanding of antimicrobial defense, the present discoveries reveal specific intersections of neurological and immunological systems and establish insights into antiinfective strategies that preserve critical functions of the CNS.     

Trends of lipoprotein variables from childhood to adulthood in offspring of parents with coronary heart disease: The Bogalusa heart study

Although dyslipidemia among offspring of parents with coronary heart disease (CHD) has been known, the development of this adverse relationship with respect to specific lipoprotein variables from childhood to young adulthood has not been elucidated. This aspect was examined in a young adult cohort with (n = 271) and without (n = 805) a parental history of CHD followed longitudinally since childhood by repeated surveys from 1973 to 1991. Trends in fasting lipoprotein variables by parental CHD status were assessed by Lowess smoothing curve and Generalized Estimating Equations (GEE). In multivariate analyses adjusted for race and sex, parental CHD associated positively with low-density lipoprotein cholesterol (LDL-C, P <.01) and triglycerides (P <.05) mainly at the young adulthood age, whereas a positive association was noted with very-low-density lipoprotein cholesterol (VLDL-C) during both childhood and young adulthood (P <.05). The positive association between parental CHD and LDL-C in young adulthood persisted independently of body mass index (BMI) and fasting insulin, but disappeared when fasting glucose was added to the model. With respect to triglycerides and VLDL-C, inclusion of BMI, insulin, and/or glucose eliminated the adverse association with parental CHD. These observations suggest that parental CHD is just one more explanatory variable that loses its partial contribution to lipoprotein profiles in their offspring when other strongly interrelated contributory variables such as age, body fatness, and measures of glucose homeostasis are taken into account. Information on these risk variables in conjunction with parental or family history of CHD may enhance the potential of CHD risk assessment in youth.     

Nutritional Factors Associated with Antenatal Depressive Symptoms in the Early Stage of Pregnancy Among Urban South Indian Women

Many women of reproductive age from developing countries have poor nutritional status, and the prevalence of depression during pregnancy is high. The objective of the present study was to assess the prevalence of antenatal depressive symptoms in early pregnancy, and to identify the demographic and nutritional factors associated with these symptoms in a sample of urban South Indian pregnant women. This cross-sectional study was the baseline assessment of a prospective randomized controlled trial of vitamin B₁₂ supplementation in urban pregnant south Indian women between the ages of 18 and 40 years (www.clinicaltrials.gov: NCT00641862). 365 women in their first trimester of pregnancy were screened for depressive symptoms at an urban clinic in Karnataka, South India, using the Kessler Psychological Distress Scale (K-10). Nutritional, clinical and biochemical factors were also assessed. Mean (SD) age of the cohort was 22.6 (3.7) years and mean (SD) BMI was 20.4 (3.3) kg/m². 121 (33 %) of the women in the 1st trimester had symptoms consistent with depression (K-10 score >6). In multivariate log binomial regression analysis, presence of antenatal depressive symptoms in the first trimester were positively associated with vomiting, prevalence ratio (PR) = 1.54 (95 % CI 1.10, 2.16) and negatively with anemia, PR = 0.67 (95 % CI 0.47, 0.96). Nutrient intakes, serum vitamin B₁₂, methylmalonic acid, homocysteine and red cell folate levels were not associated with measures of depression. Antenatal depressive symptoms in early pregnancy are highly prevalent in urban Indian women and are more common in women with vomiting and without anemia. In this cross-sectional data, blood concentrations of vitamin B₁₂ and folate were not associated with depressive symptoms. The relationship between nutritional status and depressive symptoms may require larger and longitudinal studies.     

Iodine-mediated synthesis of benzo[a]fluorenones from yne-enones

The chalcones derived from o-alkynylacetophenones and aromatic aldehydes (yne-enones) when heated under reflux with iodine in acetic acid gave a range of benzo[a]fluorenone derivatives in moderate to good yields. The transformation involves the formation of a vinyl indenone intermediate through regioselective alkyne hydration and intramolecular aldol condensation followed by electrocyclic ring closure and aromatization.

An iodine mediated synthesis of benzo[a]fluorenone derivatives from the chalcones derived from o-alkynylacetophenones and aromatic aldehydes is described.     

Study of clinical profile and management of patients with pulmonary embolism – Single center study

Objective

To study the clinical profile, diagnostic methods and management in patients with symptomatic pulmonary embolism (PE).

Methods

Retrospective assessment of clinical features and management of patients presenting with symptomatic pulmonary embolism from January 2005 to March 2012.

Results

35 patients who were newly diagnosed to have pulmonary embolism with a mean age of 52.1 years were included in the study. Dyspnea (91.4%) and syncope (22.8%) were the predominant symptoms. Echocardiography was done in all patients. 30 patients (85.7%) had pulmonary arterial hypertension, 31 patients (88.5%) had evidence of RV dysfunction and 4 patients (16.7%) had evidence of thrombus in PA, RV. Out of 35 patients, 34 patients (97.14%) showed positive d-dimer reports. Among 35 patients, 24 (68.5%) had positive troponin values. V/Q scan was done in 14 patients (40%) and CT pulmonary angiogram (CTPA) was done in 24 patients (68.5%.). Thrombolysis was done is 24 patients (68.5%). All patients received low molecular weight heparin followed by warfarin. Of the 35 patients, 34 (97.1%) were discharged and were under regular follow up for 6 months and one patient died during the hospital stay.

Conclusion

Pulmonary embolism is a common problem and can be easily diagnosed provided it is clinically suspected. Early diagnosis and aggressive management is the key to successful outcome.