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Molecules (Basel, Switzerland) Oct 2023The recent rapid growth of the battery industry has led to a rapid increase in methylene chloride emissions. Methylene chloride causes health and social problems in...
The recent rapid growth of the battery industry has led to a rapid increase in methylene chloride emissions. Methylene chloride causes health and social problems in humans. In this study, cellulose-based activated carbon fibers (CACFs) with improved yield were prepared for the removal of methylene chloride. The concentration of ammonium phosphate in the pretreatment controlled the crosslink density of cellulose fibers and improved the yield. From the results, the specific surface area and total pore volume of cellulose-based activated carbon fibers pretreated with ammonium phosphate (AP-CACFs) were determined to be 1920-2060 m/g and 0.83-1.02 cm/g, respectively, and the total yield improved by 6.78-11.59% compared to that of CACFs (4.97%). In particular, a correlation between the textural properties of CACFs and methylene chloride adsorption/desorption behavior was obtained. This correlation can be used to develop efficient adsorbents for methylene chloride removal.
PubMed: 37836838
DOI: 10.3390/molecules28196997 -
Journal of Clinical Medicine Sep 2021The precise etiology of multiple myeloma remains elusive, but both genetic and environmental factors have been suggested to contribute to disease risk. Several... (Review)
Review
The precise etiology of multiple myeloma remains elusive, but both genetic and environmental factors have been suggested to contribute to disease risk. Several occupational categories and toxic agents have been implicated as potentially causative, yet findings from the literature are inconsistent. The aim of this review was to summarize and critically comment on the accumulated epidemiological evidence, across published meta-analyses, about the association between occupational exposure and risk of multiple myeloma. Overall, results from eleven meta-epidemiological studies underscore a significantly increased risk for firefighters, hairdressers, and employees exposed to engine exhaust, whereas farming and methylene chloride exposure have been non-significantly correlated with the disease. Further epidemiological studies are of utmost importance whilst emphasis should be placed on occupational hazard surveillance, as such studies will obtain a more accurate picture of disease occurrence in working populations, and will enable both the implementation of preventive actions and the evaluation of their effectiveness.
PubMed: 34575290
DOI: 10.3390/jcm10184179 -
Environmental Pollution (Barking, Essex... Nov 2023Functionalization can change the physicochemical properties of hydrochar and improve its ability to adsorb pollutants. Herein, a trithiocyanurate-functionalized...
Functionalization can change the physicochemical properties of hydrochar and improve its ability to adsorb pollutants. Herein, a trithiocyanurate-functionalized hydrochar (TTHC) was obtained from acylation of chloroacetyl chloride and hydrochar and modification with trithiocyanuric acid in alkaline conditions. TTHC can efficiently remove cationic methylene blue (MB) and Pb(II) from wastewater. The removal can be expressed with pseudo-second-order kinetic and Langmuir models. The MB and Pb(II) removed uptakes by TTHC at 298 K exceeded 909.9 and 182.8 mg g respectively, and the removal rates reached 90% and 98% within 120 min respectively. Characterizations show TTHC is functionalized with trithiocyanurate, and rich in thiolate and aromaticity, and tends to adsorb MB/Pb(II) via multiple adsorption mechanisms. After five sorption-desorption regeneration cycles, TTHC maintained 80% and 99% adsorption capacities for MB and Pb(II) respectively. Therefore, TTHC is a promising efficient sorbent for removing MB and Pb(II) from effluents.
Topics: Water Pollutants, Chemical; Methylene Blue; Lead; Environmental Pollutants; Wastewater; Adsorption; Kinetics
PubMed: 37734632
DOI: 10.1016/j.envpol.2023.122585 -
Indian Journal of Plastic Surgery :... Jan 2021Chemical burns account for a small percentage of burns but contribute to significant number of burn-related mortalities. The major challenge posed by chemical burns is...
Chemical burns account for a small percentage of burns but contribute to significant number of burn-related mortalities. The major challenge posed by chemical burns is difficulty in correct depth estimation, as the damage continues to progress until they are effectively neutralized. Besides the most common etiology of chemical burns by alkalis and acids, there are many other unique causes of chemical burns. The author describes a case of chemical burns by heavy duty paint remover, the main composition of which is methylene chloride. Although several studies about methylene chloride poisoning are available in literature, only one case report of burns due to methylene chloride exists in literature. These burns are unique in their presentation. The author describes the presentation and challenges in management of this burn. Not applicable.
PubMed: 33814750
DOI: 10.1055/s-0041-1725224 -
Polymers May 2023This study investigated the nitration of nanostructured bacterial cellulose (NBC). The NBC, obtained using symbiotic Sa-12 as the microbial producer and then...
This study investigated the nitration of nanostructured bacterial cellulose (NBC). The NBC, obtained using symbiotic Sa-12 as the microbial producer and then freeze-dried, was nitrated herein by two methods, the first using mixed sulphuric-nitric acids (MA) and the second using concentrated nitric acid in the presence of methylene chloride (NA+MC). The synthesized samples of NBC nitrates (NBCNs) exhibited 11.77-12.27% nitrogen content, a viscosity of 1086 mPa·s or higher, 0.7-14.5% solubility in an alcohol-ester mixture, and 0.002% ash. Scanning electron microscopy showed that the nitration compacted the NBC structure, with the original reticulate pattern of the structure being preserved in full. Infrared spectroscopy for the presence of functional nitro groups at 1658-1659, 1280, 838-840, 749-751 and 693-694 cm confirmed the synthesis of cellulose nitrates in particular. Thermogravimetric and differential thermal analyses showed the resultant NBCNs to have a high purity and high specific heats of decomposition of 6.94-7.08 kJ/g. The NBCN samples differ conceptually from plant-based cellulose nitrates by having a viscosity above 1086 mPa·s and a unique 3D reticulate structure that is retained during the nitration. The findings suggest that the NBCNs can be considered for use in novel high-tech materials and science-driven fields distinct from the application fields of plant-based cellulose nitrates. The NBCN sample obtained with NA+MC has the ability to generate an organogel when it is dissolved in acetone. Because of the said property, this NBCN sample can find use as a classical adhesive scaffold and an energetic gel matrix for creating promising energetic polymers.
PubMed: 37177359
DOI: 10.3390/polym15092213 -
Journal of Applied Toxicology : JAT Oct 2020Paint and varnish removers constitute a major potential source of organic solvent exposure to contractors and home improvement enthusiasts. Unfortunately, the leading... (Review)
Review
Paint and varnish removers constitute a major potential source of organic solvent exposure to contractors and home improvement enthusiasts. Unfortunately, the leading paint remover formulations have traditionally contained, as major ingredients, chemicals classified as probable human carcinogens (eg, methylene chloride) or reproductive toxicants (eg, N-methylpyrrolidone). In addition, because of its unique toxicology (ie, hepatic conversion to carbon monoxide compounding generic solvent narcosis and arrythmogenesis), high volatility, and rigorous requirements for personal protective equipment, methylene chloride exposures from paint removers have been linked to numerous deaths involving both occupational and consumer usage. The aim of this review is to summarize the known toxicology of solvent-based paint remover constituents (including those found in substitute formulations) in order to provide health risk information to regulators, chemical formulators, and end-users of this class of products, and to highlight any data gaps that may exist.
Topics: Adult; Carcinogens; Environmental Exposure; Female; Humans; Male; Middle Aged; Occupational Exposure; Paint; Solvents; Volatile Organic Compounds
PubMed: 32342556
DOI: 10.1002/jat.3979 -
Tetrahedron Chem Dec 2022The emergence and rapid spread of coronavirus disease 2019 (COVID-19), a potentially fatal disease, caused by severe acute respiratory syndrome coronavirus-2...
The emergence and rapid spread of coronavirus disease 2019 (COVID-19), a potentially fatal disease, caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), has swiftly led to public health crisis worldwide. Hence vaccines and antiviral therapeutics are an important part of the healthcare response to combat the ongoing threat by COVID-19. Here, we report an efficient synthesis of nirmatrelvir (PF-07321332), an orally active SARS-CoV-2 main protease inhibitor.
PubMed: 36276807
DOI: 10.1016/j.tchem.2022.100033 -
BMC Complementary Medicine and Therapies Oct 2021Microbial resistance, diabetes mellitus, and obesity are global health care problems that have posed a serious threat to both human and environmental ecosystems. The...
BACKGROUND
Microbial resistance, diabetes mellitus, and obesity are global health care problems that have posed a serious threat to both human and environmental ecosystems. The goals of the present investigations are to investigate the phytoconstituents, antilipase, anti-α-amylase, and antimicrobial activity of Orobanche aegyptiaca Pers. (OA) from Palestine.
METHODS
Identification of the phytoconstituents of OA plant petroleum ether, methylene chloride, chloroform, acetone, and methanol extracts were conducted using pharmacopeia's methods, while porcine pancreatic lipase and α-amylase inhibitory activities were examined using p-nitrophenyl butyrate and 3,5-dinitro salicylic acid methods, respectively. Moreover, the antimicrobial activity was evaluated utilizing broth microdilution assay against eight bacterial and fungal strains.
RESULTS
The phytochemical screening results showed that the methanol extract of the OA plant is rich in phytochemical components, also this extract has powerful antilipase potential with an IC value of 19.49 ± 0.16 μg/ml comparing with the positive control (Orlistat) which has antilipase activity with IC value of 12.3 ± 0.35 μg/ml. Moreover, the methanol and chloroform extracts have powerful α-amylase inhibitory activity with IC values of 28.18 ± 0.22 and 28.18 ± 1.22 μg/ml, respectively comparing with Acarbose which has α-amylase inhibitory activity with IC dose of 26.3.18 ± 0.28 μg/ml. The antibacterial results showed that the methylene chloride extract exhibited the highest antibacterial activity among the other OA plant extracts with a MIC value of 0.78 mg/ml against S. aureus, while, the methylene chloride, petroleum ether, and chloroform extracts of the OA plant showed potential antifungal activity against C. albicans strains with MIC value of 0.78 mg/ml.
CONCLUSION
The OA methanol and chloroform extracts could be excellent candidates as antilipase and anti-α-amylase bioactive materials. In addition, methylene chloride, petroleum ether, and chloroform extracts could be potential natural antimicrobial products.
Topics: Animals; Anti-Infective Agents; Anti-Obesity Agents; Humans; Hypoglycemic Agents; Lipase; Microbial Sensitivity Tests; Middle East; Orobanche; Phytochemicals; Swine; alpha-Amylases
PubMed: 34625075
DOI: 10.1186/s12906-021-03431-x -
Drug Development Research Jun 2022Amyloid precursor-like protein-2 (APLP2) and its C-terminal fragments (CTFs) are expressed at high levels in pancreatic cancer cells and knockdown of APLP2 expression...
Amyloid precursor-like protein-2 (APLP2) and its C-terminal fragments (CTFs) are expressed at high levels in pancreatic cancer cells and knockdown of APLP2 expression inhibits tumor growth. CTFs are released from APLP2 by beta-secretase (BACE). In this study, our goal was to determine whether methylene blue (MethB) and toluidine blue O (TBO) could be used to slow down the growth and viability of pancreatic cancer cells (Hs 766T). We found that TBO and MethB decreased the growth and viability of Hs 766T cells in a dose- and time-dependent manner compared to vehicle-treated control, as demonstrated by MTT and trypan blue exclusion assays. Although TBO led to decreased expression of APLP2, MethB did not show any significant effect on APLP2. However, both MethB and TBO reduced BACE activity and the levels of APLP2 CTFs in Hs 766T cells. In conclusion, MethB and TBO may be valuable candidates for the treatment of pancreatic cancer by targeting APLP2 processing.
Topics: Amyloid Precursor Protein Secretases; Amyloid beta-Protein Precursor; Humans; Methylene Blue; Pancreatic Neoplasms; Tolonium Chloride
PubMed: 35092039
DOI: 10.1002/ddr.21915 -
ACS Omega Dec 2022Amphiphilic aryl radicals generated upon visible light irradiation of arylazo sulfones have been exploited in the development of a solventylation strategy via hydrogen...
Amphiphilic aryl radicals generated upon visible light irradiation of arylazo sulfones have been exploited in the development of a solventylation strategy via hydrogen atom transfer (HAT). The present protocol succeeded in the versatile functionalization of various olefins with carbon-centered radicals deriving from acetone, acetonitrile, chloroform, methylene chloride, nitromethane, methyl acetate, and methyl formate under metal- and photocatalyst-free conditions. The direct addition of the aryl radicals onto the olefin substrates was suppressed under high dilution conditions.
PubMed: 36591128
DOI: 10.1021/acsomega.2c07172