Ovicidal and Oviposition Deterrent Activities of Medicinal Plant Extracts Against Aedes aegypti L. and Culex quinquefasciatus Say Mosquitoes (Diptera: Culicidae)

Objectives

To evaluate the ovicidal and oviposition deterrent activities of five medicinal plant extracts namely Aegle marmelos (Linn.), Limonia acidissima (Linn.), Sphaeranthus indicus (Linn.), Sphaeranthus amaranthoides (burm.f), and Chromolaena odorata (Linn.) against Culex quinquefasciatus and Aedes aegypti mosquitoes. Three solvents, namely hexane, ethyl acetate, and methanol, were used for the preparation of extracts from each plant.

Methods

Four different concentrations—62.5 parts per million (ppm), 125 ppm, 250 ppm, and 500 ppm—were prepared using acetone and tested for ovicidal and oviposition deterrent activities. One-way analysis of variance (ANOVA) was used to determine the significance of the treatments and means were separated by Tukey''s test of comparison.

Results

Among the different extracts of the five plants screened, the hexane extract of L. acidissima recorded the highest ovicidal activity of 79.2% and 60% at 500 ppm concentration against the eggs of Cx. quinquefasciatus and Ae. aegypti, respectively. Similarly, the same hexane extract of L. acidissima showed 100% oviposition deterrent activity at all the tested concentrations against Cx. quinquefasciatus and Ae. aegypti adult females.

Conclusion

It is concluded that the hexane extract of L. acidissima could be used in an integrated mosquito management program.     

Larvicidal and pupicidal activities of ecbolin A and ecbolin B isolated from Ecbolium viride (Forssk.) Alston against Culex quinquefasciatus Say (Diptera: Culicidae)

The mosquitocidal activity of different fractions and isolated compounds from the ethyl acetate extract of Ecbolium viride root was assessed on larvae and pupae of Culex quinquefasciatus Say (Diptera: Culicidae). The larvae and pupae were exposed to concentrations of 6.125, 12.5, 25 and 50 ppm for fractions and 1, 2.5, 5 and 10 ppm for compound. Among the 12 fractions screened, fraction 6 from the ethyl acetate extract of E. viride was recorded to have the highest larvicidal and pupicidal activities against C. quinquefasciatus. The lethal concentration (LC₅₀ and LC₉₀) values of fraction 6 were 4.26 and 9.0 ppm against C. quinquefasciatus larvae and 6.55 and 12.19 ppm against C. quinquefasciatus pupae, respectively, in 24 h. Fraction 7 was recorded to have moderate activity with LC₅₀ and LC₉₀ values of 11.25 and 25.02 ppm against C. quinquefasciatus larvae and 13.33 and 31.15 ppm against C. quinquefasciatus pupae, respectively, in 24 h. Ecbolin A and ecbolin B were identified from fractions 7 and 6, respectively. The structure of the isolated compounds was identified on the basis of spectral data (¹H NMR and ¹³C NMR) and compared with literature spectral data. Further, the isolated compound, ecbolin B, from fraction 6 was recorded to have strong larvicidal and pupicidal activities than ecbolin A. The LC₅₀ and LC₉₀ values of ecbolin B on C. quinquefasciatus larvae were 1.36 and 2.76 ppm, and on pupae, these were 1.54 and 3.51 ppm, respectively. The present results suggest that ecbolin B could be used as a mosquitocidal agent against C. quinquefasciatus.     

Anti-inflammatory and anti-arthritic effects of 3-hydroxy, 2-methoxy sodium butanoate from the leaves of Clerodendrum phlomidis L.f.

Introduction

The leaves of Clerodendrum phlomidis L.f. have been used in the Indian traditional system of medicine to treat several inflammatory diseases and arthritis. The aim of the present study was to assess the anti-inflammatory and anti-arthritic activities of the leaves of C. phlomidis and to isolate the active principle by bioactivity guided fractionation.

Materials and methods

To find the anti-inflammatory constituents from this plant, fractionations were performed with concurrent bioassays. Carrageenan-induced inflammation and Freund complete adjuvant (FCA)-induced arthritic rat models were used. The anti-inflammatory and anti-arthritic activities of the isolated compound were studied by assessing the histology of the joints, levels of lysosomal enzymes, protein-bound carbohydrates, acute phase protein, etc., in plasma, as well as by estimating the levels and expression of pro-inflammatory cytokines in the joints.

Results

Repeated fractionations and bioassays yielded a novel bioactive compound: 3-hydroxy, 2-methoxy-sodium butanoate. Treatment with this compound reduced the paw edema induced by carrageenan and FCA dose dependently. The levels of lysosomal enzymes and protein-bound carbohydrates decreased significantly upon treatment with the compound. The level of plasma acute phase protein was also decreased compared with control animals. Protein levels and mRNA expression of pro-inflammatory cytokines TNF, IL-1 and IL-6 in the joints were decreased significantly in a dose-dependent manner and the histopathological data also added evidence of the anti-arthritic property of the compound.

Conclusion

The 3-hydroxy,2-methoxy sodium butanoate isolated from plant leaves displays considerable potency in anti-inflammatory action and has a prominent anti-arthritic effect. This is the first report of this natural compound with bioactivity.     

Synthesis,supramolecular organization and thermotropic phase behaviour of N-acyltris(hydroxymethyl)aminomethane

Herein, we reported the supramolecular organization of N-acyltris(hydroxymethyl)aminomethane (NATM) in the solid state as well as in aqueous solution. Single crystal X-ray diffraction revealed that NATM adopts a fully interdigitized structure. The thermodynamic parameters associated with thermotropic phase behaviour of NATM was determined by differential scanning calorimetry. The molecular packing and phase state of the NATM analyzed by laurdan and prodan fluorescence supports the formation of an interdigitized phase in aqueous solution. The potential application of the self-assembled NATM vesicles was demonstrated through entrapping model drug, Rhodamine B.

Self assembly of N-acyltris(hydroxymethyl)aminomethane into interdigitized vesicles.     

Myroides pelagicus from the Gut of Drosophila melanogaster Attenuates Inflammation on Dextran Sodium Sulfate-Induced Colitis

Background and Aim

Probiotics are live microorganisms that confer a health benefit on the host when administered in adequate amounts. In the present study, the putative probiotic strain was identified from the gut of Drosophila melanogaster and assessed for its protective effect in inflammatory bowel disease.

Methods

Active probiotics were screened from the Drosophila melanogaster gut by the selection criteria of gastric juice tolerance, hydrophobic property, antimicrobial potential, adhesion, and invasion properties. The active probiotics were identified by 16s rDNA sequencing and the effect of these active probiotics was evaluated in a Dextran sulphate sodium (DSS)-induced mice model by estimating inflammatory markers and histopathological changes.

Results

Nine Gram-positive and bile salt tolerant bacterial isolates were obtained from the gut samples. The isolates PTH 2, PTH 4, and PTH 7 clearly showed significant activity in antimicrobial potential, hydrophobic (>74 %) property, and intestinal juice tolerance. Among these, PTH 7 was selected for further studies due to its significant low-invasion ability and it proved capable of reducing the secretion of proinflammatory cytokines. The 16s rDNA studies revealed that PTH 7 was Myroides pelagicus. Administration of M. pelagicus to the DSS-induced colitic animals significantly suppressed myeloperoxidase, ALP, and malondialdehyde levels, and also lowered levels of proinflammatory cytokine expression. Further, the recovery from the disease by the probiotic treatment was supported by histopathological and macroscopic observation. The treated animals did not show any adverse signs in their physiology or behavior.

Conclusion

Myroides pelagicus successfully prohibited inflammatory markers and acted as a potent probiotic. Future studies with this stain might prove its efficacy as a drug for the management of colitis.     

Beneficial Antioxidative and Antiperoxidative Effect of Cinnamaldehyde Protect Streptozotocin-Induced Pancreatic β-Cells Damage in Wistar Rats

The present study was aimed to evaluate the antioxidant defense system of cinnamaldehyde in normal, diabetic rats and its possible protection of pancreatic β-cells against its gradual loss under diabetic conditions. In vitro free radical scavenging effect of cinnamaldehyde was determined using DPPH (1,1-diphenyl-2-dipicrylhydrazyl), superoxide radical, and nitric oxide radical. Streptozotocin (STZ) diabetic rats were orally administered with cinnamaldehyde at concentrations of 5, 10 and 20 mg/kg body weight for 45 days. At the end of the experiment, the levels of plasma lipid peroxides and antioxidants such as vitamin C, vitamin E, ceruloplasmin, catalase, superoxide dismutase, reduced glutathione and glutathione peroxidase were determined. A significant increase in the levels of plasma glucose, vitamin E, ceruloplasmin, and lipid peroxides and significant decrease in the levels of plasma insulin and reduced glutathione were observed in the diabetic rats. Also the activities of pancreatic antioxidant enzymes were altered in the STZ-induced diabetic rats. The altered enzyme activities were reverted to near-normal levels after treatment with cinnamaldehyde and glibenclamide. Histopathological studies also revealed a protective effect of cinnamaldehyde on pancreatic β-cells. Cinnamaldehyde enhances the antioxidant defense against reactive oxygen species produced under hyperglycemic conditions and thus protects pancreatic β-cells against their loss and exhibits antidiabetic properties.     

Association between pre-intensive care unit (ICU) hospital length of stay and ICU outcomes in a resource-limited setting

Background Previous studies demonstrated higher mortality for patients with a longer pre-intensive care unit (ICU) hospital length of stay (LOS), in well-resourced settings. Objectives The study aimed to determine the association between pre-ICU hospital LOS and ICU outcomes in a resource-limited setting. We hypothesised that longer pre-ICU hospital LOS would be associated with higher ICU mortality. Methods This was a retrospective cohort study measuring the association between pre-ICU hospital LOS and ICU outcomes using data extracted from a regional hospital ICU in KwaZulu-Natal, South Africa. Consecutive ICU admissions of all patients (medical and surgical) older than 18 years were included during the study period September 2014 to August 2018. A corrected sample size of 2 040 patients was identified. Multivariable logistic regression was used to assess the primary outcome of ICU mortality, and multivariable Cox proportional hazard regression was used for the secondary outcome of ICU LOS. Results The median pre-ICU hospital LOS was 1 day (interquartile range (IQR) 0 - 2 days). The median length of ICU stay was 2.4 days (IQR 1.1 - 4.8 days) and the observed ICU mortality was 16% (n=327/2 040). Pre-ICU hospital LOS was not associated with ICU mortality in the unadjusted (odds ratio (OR) 1.00; 95% confidence interval (CI) 0.98 - 1.02; p=0.68; n=2 040) and fully adjusted logistic regression models (OR 1.00; 95% CI 0.98 - 1.03; p=0.90; n=1 981) using a complete case analysis for missing patient-level covariates. In Cox proportional hazard models, there was no association between pre-ICU hospital LOS and ICU LOS (hazard ratio 1.00; 95% CI 0.98 - 1.03; p=0.72; n=1 967), including when stratified by admission source. Conclusion Pre-ICU hospital LOS was not associated with either ICU mortality or ICU LOS in a resource-limited setting. Future studies should aim to include multicentre data and evaluate long-term outcomes. Contributions of the study The study was conducted in a resource-limited setting and found no association between prolonged LOS pre-ICU and patient outcomes. Several potential explanations for this observation have been explored. This important subject is pertinent to the appropriate use of limited resources and encourages future studies to evaluate this association and to consider longer-term outcomes (e.g. 30-day mortality) in future findings.     

Anti-inflammatory activity of Albizia lebbeck Benth., an ethnomedicinal plant, in acute and chronic animal models of inflammation

Aim of the study

Albizia lebbeck Benth. is used both in Indian traditional system and folk medicine to treat several inflammatory pathologies such as asthma, arthritis and burns. The aim of the present study was to evaluate the scientific basis of anti-inflammatory activity of different organic solvent extracts of Albizia lebbeck.

Materials and methods

The anti-inflammatory activity of Albizia lebbeck was studied using the carrageenan, dextran, cotton pellet and Freund's complete adjuvant induced rat models. The extracts obtained using petroleum ether, chloroform and ethanol were administered at the concentrations of 100, 200 and 400 mg/kg body weight.

Results

The petroleum ether and ethanol extracts at 400 mg/kg, showed maximum inhibition of inflammation induced by carrageenan (petroleum ether—48.6%; ethanol—59.57%), dextran (petroleum ether—45.99%; ethanol—52.93%), cotton pellet (petroleum ether—34.46%; ethanol—53.57%) and Freund's adjuvant (petroleum ether—64.97%; ethanol—68.57%).

Conclusion

The marked inhibitory effect on paw edema shows that Albizia lebbeck possesses remarkable anti-inflammatory activity, supporting the folkloric usage of the plant to treat various inflammatory diseases.     

ADAM28: A potential oncogene involved in asbestos‐related lung adenocarcinomas

Asbestos‐related lung cancer accounts for 4–12% of all lung cancers worldwide. Since putative mechanisms of carcinogenesis differ between asbestos and tobacco induced lung cancers, tumors induced by the two agents may be genetically distinct. To identify gene expression biomarkers associated with asbestos‐related lung tumorigenicity we performed gene expression array analysis on tumors of 36 patients with primary lung adenocarcinoma, comparing 12 patients with lung asbestos body counts above levels associated with urban dwelling (ARLC‐AC: asbestos‐related lung cancer‐adenocarcinoma) with 24 patients with no asbestos bodies (NARLC‐AC: non‐asbestos related lung cancer‐adenocarcinoma). Genes differentially expressed between ARLC‐AC and NARLC‐AC were identified on fold change and P value, and then prioritized using gene ontology. Candidates included ZNRF3, ADAM28, PPP1CA, IRF6, RAB3D, and PRDX1. Expression of these six genes was technically and biologically replicated by qRT‐PCR in the training set and biologically validated in three independent test sets. ADAM28, encoding a disintegrin and metalloproteinase domain protein that interacts with integrins, was consistently upregulated in ARLC across all four datasets. Further studies are being designed to investigate the possible role of this gene in asbestos lung tumorigenicity, its potential utility as a marker of asbestos related lung cancer for purposes of causal attribution, and its potential as a treatment target for lung cancers arising in asbestos exposed persons. © 2010 Wiley‐Liss, Inc.