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Journal of Pharmacy & Bioallied Sciences Nov 2021The aim of the study is to investigate the effect of joint surface preparations and chemical surface treatment given to prepared surface on the transverse strength of...
AIM
The aim of the study is to investigate the effect of joint surface preparations and chemical surface treatment given to prepared surface on the transverse strength of repaired denture base resin.
METHODOLOGY
Two hundred and twenty specimens (DPI India) were randomly allocated into eight groups ( = 10), according to the combination of joint surface preparation (Butt joint, 45° bevel, and rounded joint) and chemical surface treatment (methylene chloride, ethyl acetate, and methyl methacrylate) for 30 and 60 s each. Specimens, after surface treatment, were repaired with self-cured resin (DPI India) and then subjected to 3-point bending test to measure transverse strength. Fractured surfaces were viewed under stereomicroscope and subjected to AutoCAD analysis to determine type of failure (adhesive or cohesive) and measure their area. Measurement data were analyzed by one-way analysis of variance, paired -test, Dunnett's D test, and multiple comparison Bonferroni -test, with a 5% significance level.
RESULTS
Most of the comparisons between the test specimens were statistically significant. Specimens (methylene chloride for 60 s and rounded joint) show 60%-70% gain of strength.
CONCLUSIONS
For providing better bond strength to a repaired specimen, the segment of fractured specimens to be provided "Rounded joint" preparation with etching by methylene chloride for 60 s.
PubMed: 35017918
DOI: 10.4103/jpbs.jpbs_217_21 -
Molecules (Basel, Switzerland) Sep 2022Lam (syn. .) leaves are globally acclaimed for their nutritional content and mitigation of malnutrition. In most impoverished rural communities including Limpopo,...
Lam (syn. .) leaves are globally acclaimed for their nutritional content and mitigation of malnutrition. In most impoverished rural communities including Limpopo, Mpumalanga and KwaZulu Natal of South Africa, powdered leaves of are applied as a nutritional supplement for readily available food such as porridge for malnourished children and even breast-feeding mothers. Widely practiced and admired is also the use of the plant seed in the do-it-yourself purification of water by rural South Africans. This study aimed at identifying the chemical and nutritional marker compounds present in South African seed oils using high resolution 1-2-dimension gas chromatography in order to give scientific validation to its uses in cosmetics and particularly in culinary practices. Results obtained from two-dimension tandem mass spectrometry chemical signature revealed over 250 compounds, five times more than those reported from one-dimension gas chromatography. Whereas previous reports from gas chromatography-mass spectrometry analysis reported oleic acid (70-78%) as the major compound from oil samples from other countries, seed oil from South Africa is marked by 13-octadeaconic acid with 78.62% and 41.9% as the predominant monounsaturated fatty acid in the hexane and dichloromethane extracts respectively. This was followed by vaccenic acid, an isomer of oleic acid at 51% in the acetone extract, 9-octadecanoic acid-(z)-methyl ester at 39.18%, 21.34% and 10.06% in dichloromethane, hexane and acetone extracts respectively. However, a principal component analysis with R = 0.98 of the two-dimension tandem mass spectrometry cum chemometric analysis indicated n-hexadecanoic acid, oleic acid, 9-octadecanoic acid-(z)-methyl ester and -vaccenic acid with a probability of 0.96, 0.88, 0.80 and 0.79 respectively as the marker compounds that should be used for the quality control of seed oils from South Africa. This study demonstrates that South African oils contain C-18 monounsaturated fatty acids similar to oils from Egypt (76.2%), Thailand (71.6%) and Pakistan (78.5%) just to mention but a few. These fatty acids are sunflower and olive oil type-compounds and therefore place seed oil for consideration as a cooking oil amongst its other uses.
Topics: Acetone; Child; Esters; Fatty Acids; Gas Chromatography-Mass Spectrometry; Hexanes; Humans; Methylene Chloride; Moringa; Moringa oleifera; Oleic Acid; Olive Oil; Palmitic Acid; Plant Extracts; Plant Oils; Seeds; South Africa; Stearic Acids; Water
PubMed: 36144484
DOI: 10.3390/molecules27185749 -
Antioxidants (Basel, Switzerland) Feb 2021Since 2016, the invasive halophyte has been colonizing mudflats along the western coast of South Korea. In order to minimize costs on expansion management and...
Since 2016, the invasive halophyte has been colonizing mudflats along the western coast of South Korea. In order to minimize costs on expansion management and waste-treatment of collected biomass, the potential application of the collected biomass of was investigated. Ethanolic extracts and subfractions thereof (hexanes, methylene chloride, ethyl acetate, 1-butanol, and water-soluble) of the aerial and belowground parts of showed free radical-scavenging [2,2-diphenyl-1-picrylhydrazyl (DPPH), and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS)], tyrosinase inhibitory, and pancreatic lipase inhibitory activities. An ethyl acetate fraction derived from aerial parts (EA-a) showed the most potent radical-scavenging and pancreatic lipase inhibitory activities, whereas tyrosinase inhibition was mainly observed in the methylene chloride soluble fractions (MC-bg) and other lipophilic fractions (ethyl acetate and hexanes layers) obtained from belowground parts. The major EA-a compound isolated and identified was 1,3-di---feruloyl quinic acid () based on spectroscopic analysis, whereas the two major MC-bg compounds were identified as -hydroxybenzaldehyde () and --feruloyltyramine (). Compounds and scavenged both DPPH and ABTS radicals, whereas and inhibited pancreatic lipase activity. These results indicate that extracts and fractions of have antioxidant, anti-obesity, and whitening properties with potential pharmaceutical, cosmeceutical, and functional food applications.
PubMed: 33557332
DOI: 10.3390/antiox10020242 -
Scandinavian Journal of Work,... 1979Whole-body autoradiography has been used to study the distribution and fate of 14C-labeled benzene, toluene, xylene, styrene, methylene chloride, chloroform, carbon...
Whole-body autoradiography and allied tracer techniques in distribution and elimination studies of some organic solvents: benzene, toluene, xylene, styrene, methylene chloride, chloroform, carbon tetrachloride and trichloroethylene.
Whole-body autoradiography has been used to study the distribution and fate of 14C-labeled benzene, toluene, xylene, styrene, methylene chloride, chloroform, carbon tetrachloride and trichloroethylene in mice after inhalational exposure. Total radioactivity, including the volatile part of the solvents were registered by autoradiography of dried, evaporated tape-fastened sections. In addition, dried, evaporated tape-fastened sections were extracted with water, trichloroacetic acid and a series of organic solvents and autoradiographed to register organs where metabolites were firmly bound. In another facet of the study, the quantitative elimination of the solvents and their metabolites via various routes was investigated. The expiration of unchanged solvents was subject to mathematical and computerized compartmental pharmacokinetic analysis. All solvents were rapidly taken up in fatty and nervous tissues where they were retained for different periods of time largely dependent on their fat solubility. Unexpectedly long retention times were noted for the chlorinated solvents, particularly for chloroforn, which showed a specific long-term retention in the cerebellum, meninges and spinal nerves, indicating interactions with specific nervous tissue receptors. Solvent metabolites appeared rapidly in several organs, mainly the liver and kidney, and were excreted both via urine and bile. Toluene and xylene metabolites were completely extractable whereas firmly bound metabolites were registered after inhalation of benzene, styrene and all chlorinated solvents, notably in the liver and kidney but also in the bronchi of the lung. Three-compartment pharmacokinetics were observed for the majority of the solvents selected for study although a two-compartment model was found to fit the elimination rate curves for styrene, methylene chloride and chloroform in the exhaled air. The fat solubility of the solvents was found to influence their pharmacokinetics since lower rate constants were generally obtained for the expiration of more fat soluble solvents.
Topics: Adipose Tissue; Animals; Autoradiography; Benzene; Carbon Radioisotopes; Carbon Tetrachloride; Chemical Phenomena; Chemistry; Chloroform; Guinea Pigs; Methylene Chloride; Nervous System; Solvents; Styrenes; Temperature; Tissue Distribution; Toluene; Trichloroethylene; Xylenes
PubMed: 424704
DOI: No ID Found -
Clinical Parkinsonism & Related... 2021Epidemiologic and toxicology studies suggest that exposure to various solvents, especially chlorinated hydrocarbon solvents, might increase Parkinson disease (PD) risk.
INTRODUCTION
Epidemiologic and toxicology studies suggest that exposure to various solvents, especially chlorinated hydrocarbon solvents, might increase Parkinson disease (PD) risk.
METHODS
In a population-based case-control study in Finland, we examined whether occupations with potential for solvent exposures were associated with PD. We identified newly diagnosed cases age 45-84 from a nationwide medication reimbursement register in 1995-2014. From the population register, we randomly selected non-PD controls matched on sex, along with birth and diagnosis years (age). We included 11,757 cases and 23,236 controls with an occupation in the 1990 census, corresponding to age 40-60. We focused on 28 occupations with ≥ 5% probability of solvent exposure according to the Finnish Job Exposure Matrix. We estimated odds ratios (ORs) and 95% confidence intervals (CIs) by logistic regression modeling, adjusting for age, sex, socioeconomic status, and smoking probability.
RESULTS
Similar proportions of cases (5.5%) and controls (5.6%) had an occupation with potential exposure to any solvents. However, all occupations with a point estimate above one, and all significantly or marginally significantly associated with PD (electronic/telecommunications worker [OR = 1.63, 95% CI 1.05-2.50], laboratory assistant [OR = 1.40, 95% CI 0.98-1.99], and machine/engine mechanic [OR = 1.23, 95% CI 0.99-1.52]) entailed potential for exposure to chlorinated hydrocarbon solvents, specifically. Secondary analyses indicated exposure to polycyclic aromatic hydrocarbons and some metals might contribute to the association for mechanics.
CONCLUSION
PD risk might be slightly increased in occupations with potential exposure to chlorinated hydrocarbon solvents. Confirmation is required in additional studies that adjust for other occupational exposures and smoking.
PubMed: 34316670
DOI: 10.1016/j.prdoa.2021.100092 -
Molecules (Basel, Switzerland) Dec 2023Lily is one of the most important cut flowers in the world, with a rich floral fragrance. To further explore the fragrance emission mechanisms of lily cultivars,...
Lily is one of the most important cut flowers in the world, with a rich floral fragrance. To further explore the fragrance emission mechanisms of lily cultivars, headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) and organic solvent extraction-gas chromatography-mass spectrometry (OSE-GC-MS) were used to unveil the volatile organic compounds (VOCs) and endogenous extracts of seven lily cultivars. Furthermore, real-time quantitative PCR (qRT-PCR) was used to determine the expression levels of two key genes ( and ) related to the biosynthesis of monoterpenoids and methyl benzoate. The results show that forty-five VOCs were detected in the petals of seven lily cultivars, and the main compounds were monoterpenoids and phenylpropanoids/benzenoids. Dichloromethane was the best solvent for extracting the endogenous extracts of 'Viviana' petals and eighteen endogenous extracts were detected using dichloromethane to extract the petals of seven lily cultivars. Each compound's emission ratio (natural logarithm of the ratio of VOC content to endogenous extract content) was calculated, and linear regression analyses between emission ratios and boiling points were conducted. Significant linear negative correlations existed between the emission ratios and boiling points of compounds, and the regression equations' coefficients of determination () were all greater than 0.7. was expressed highly in 'Viviana', 'Pink News', and 'Palazzo', and was expressed highly in 'Pink News' and 'Palazzo'. Correlation analyses between the gene expression levels and the monoterpenoids and methyl benzoate contents found that the expression levels have strong positive correlations with monoterpenoids content, while no correlations were found between the expression levels of and the contents of methyl benzoate. This study lays the foundation for research on the release patterns of VOCs in the flowers of , and the breeding of lilies for their floral fragrance.
Topics: Lilium; Volatile Organic Compounds; Methylene Chloride; Plant Breeding; Flowers; Solid Phase Microextraction; Solvents; Monoterpenes
PubMed: 38138428
DOI: 10.3390/molecules28247938 -
Canadian Medical Association Journal Jun 1923
PubMed: 20314714
DOI: No ID Found -
BMC Complementary Medicine and Therapies Feb 2022Acquired immunodeficiency syndrome (AIDS) is a clinical syndrome resulting from infection with human immunodeficiency virus (HIV), which causes profound...
BACKGROUND
Acquired immunodeficiency syndrome (AIDS) is a clinical syndrome resulting from infection with human immunodeficiency virus (HIV), which causes profound immunosuppression. Anti-HIV drugs that are currently available are chemically synthesized and are frequently limited by side effects, the emergence of drug resistance, affordability, and availability, with over 5 million people in the world lacking access to treatment. As a result, to discover new anti-HIV agents, we investigated the effects of Kenyan C. dichogamus extracts on the laboratory-adapted strain HIV-1 in human T-lymphocytic MT-4 cells.
METHODS
Four soluble fractions of 1:1 v/v CHCl:MeOH extract of the twigs of C. dichogamus Pax were tested for their replication inhibition activity against the laboratory-adapted strain HIV-1 in the human T-lymphocytic MT-4 cell line. The plant extracts were further evaluated for their cytotoxicity in MT-4 cells using the MTT assay.
RESULTS
The cytotoxicity CC values of the methanol and methylene chloride soluble fractions of C. dichogamus were found to be between 19.58 ± 0.79 and 167 ± 0.8 µg/ml, respectively. The hexane, methylene chloride, and methanol soluble fractions of the 1:1 v/v CHCl:MeOH extract of the twigs of C. dichogamus showed inhibition of the HIV-1 laboratory-adapted strain in a virus-infected cell culture antiviral assay. The methanol soluble fraction of the 1:1 v/v CHCl:MeOH extract of the twigs of C. dichogamus showed significant anti-HIV activity by inhibiting more than 90% of viral-induced cytopathic effects with an IC value of 0.06 ± 0.01 µg/ml, giving an SI of 318.5.
CONCLUSION
Based on our findings, the methanol soluble fraction of the 1:1 v/v CHCl:MeOH extract of the twigs of C. dichogamus has shown potential efficacy in inhibiting viral replication and could be considered a promising candidate for further studies.
Topics: Croton; HIV Infections; HIV-1; Humans; Kenya; Plant Extracts
PubMed: 35216601
DOI: 10.1186/s12906-022-03532-1 -
International Journal of Environmental... May 2023Dichloromethane (DCM) is recognized as a very harmful air pollutant because of its strong volatility and difficulty to degrade. Ionic liquids (ILs) are considered as...
Dichloromethane (DCM) is recognized as a very harmful air pollutant because of its strong volatility and difficulty to degrade. Ionic liquids (ILs) are considered as potential solvents for absorbing DCM, while it is still a challenge to develop ILs with high absorption performances. In this study, four carboxyl-functionalized ILs-trioctylmethylammonium acetate [N][Ac], trioctylmethylammonium formate [N][FA], trioctylmethylammonium glycinate [N][Gly], and trihexyl(tetradecyl)phosphonium glycinate [P][Gly]-were synthesized for DCM capture. The absorption capacity follows the order of [P][Gly] > [N][Gly] > [N][FA] > [N][Ac], and [P][Gly] showed the best absorption capacity, 130 mg DCM/g IL at 313.15 K and a DCM concentration of 6.1%, which was two times higher than the reported ILs [Beim][EtSO] and [Emim][Ac]. Moreover, the vapor-liquid equilibrium (VLE) of the DCM + IL binary system was experimentally measured. The NRTL (non-random two-liquid) model was developed to predict the VLE data, and a relative root mean square deviation (rRMSD) of 0.8467 was obtained. The absorption mechanism was explored via FT-IR spectra, H-NMR, and quantum chemistry calculations. It showed a nonpolar affinity between the cation and the DCM, while the interaction between the anion and the DCM was a hydrogen bond. Based on the results of the study of the interaction energy, it was found that the hydrogen bond between the anion and the DCM had the greatest influence on the absorption process.
Topics: Ionic Liquids; Methylene Chloride; Spectroscopy, Fourier Transform Infrared; Anions
PubMed: 37239516
DOI: 10.3390/ijerph20105787 -
PloS One 2013This research highlights the chemical composition, antioxidant and antibacterial activities of essential oils and various crude extracts (using methanol and methylene...
This research highlights the chemical composition, antioxidant and antibacterial activities of essential oils and various crude extracts (using methanol and methylene chloride) from Syzygium cumini leaves. Essential oils were analyzed by gas chromatography-mass spectrometry (GC-MS).The abundant constituents of the oils were: α-pinene (32.32%), β-pinene (12.44%), trans-caryophyllene (11.19%), 1, 3, 6-octatriene (8.41%), delta-3-carene (5.55%), α-caryophyllene (4.36%), and α-limonene (3.42%).The antioxidant activities of all extracts were examined using two complementary methods, namely diphenylpicrylhydrazyl (DPPH) and ferric reducing power (FRAP). In both methods, the methanol extract exhibited a higher activity than methylene chloride and essential oil extracts. A higher content of both total phenolics and flavonoids were found in the methanolic extract compared with other extracts. Furthermore, the methanol extract had higher antibacterial activity compared to methylene chloride and the essential oil extracts. Due to their antioxidant and antibacterial properties, the leaf extracts from S. cumini may be used as natural preservative ingredients in food and/or pharmaceutical industries.
Topics: Anti-Bacterial Agents; Antioxidants; Bacteria; Complex Mixtures; Flavonoids; Free Radical Scavengers; Microbial Sensitivity Tests; Oils, Volatile; Oxidation-Reduction; Phenols; Plant Leaves; Syzygium
PubMed: 23593183
DOI: 10.1371/journal.pone.0060269