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1.
J Agric Food Chem ; 71(8): 3800-3812, 2023 Mar 01.
Article in English | MEDLINE | ID: mdl-36802600

ABSTRACT

Lignin, the second largest component of biomass, is considered as an important alternative source of fossil reserves for the production of fuels and chemicals. Here, we developed a novel method to oxidatively degrade organosolv lignin into value-added four-carbon esters, particularly diethyl maleate (DEM), with the cooperative catalyst consisting of 1-(3-sulfobutyl) triethylammonium hydrogen sulfate ([BSTEA]HSO4) and 1-butyl-3-methylimidazolium ferric chloride ([BMIM]Fe2Cl7). Under optimized conditions (1.00 MPa initial O2 pressure, 160 °C, 5 h), the lignin aromatic ring was effectively cleaved by oxidation to form DEM with a yield of 15.85% and a selectivity of 44.25% in the presence of the synergistic catalyst of [BMIM]Fe2Cl7-[BSMIM]HSO4 (1/3, mol/mol). The structure and composition analysis of lignin residues and liquid products confirmed that the aromatic units in lignin were effectively and selectively oxidized. Furthermore, the catalytic oxidation of lignin model compounds was explored for obtaining a possible reaction pathway of oxidative cleavage of lignin aromatic units to DEM. This study provides a promising alternative method for the production of traditional petroleum-based chemicals.


Subject(s)
Ionic Liquids , Ionic Liquids/chemistry , Lignin/chemistry , Triticum , Catalysis , Oxidative Stress
2.
J Agric Food Chem ; 71(4): 2026-2037, 2023 Feb 01.
Article in English | MEDLINE | ID: mdl-36668990

ABSTRACT

The facile, green, and efficient strategy for the separation of lignin from straw and subsequent production of value-added chemicals is crucial to the current utilization of straw. Herein, up to 23.72% of lignin was isolated from wheat stalk over cheap and green 1-(3-sulfobutyl) triethylammonium hydrogen sulfate ([BSTEA]HSO4) in aqueous ethanol (Vethanol: Vwater = 4:1). The acquired lignin was verified as a p-hydroxyphenyl-guaiacyl-syringyl type, which had a narrower molecular weight distribution, better thermal stability, and higher purity compared with those of the lignin obtained using 1-methyl-3-(4-sulfobutyl)-imidazolium hydrogen sulfate and 1-(3-sulfobutyl) pyridinium hydrogen sulfate. Moreover, a carbohydrate-rich liquid containing [BSTEA]HSO4 was obtained by water removal from the waste liquid after lignin separation and further converted to ethyl levulinate (EL) by a one-pot process in the presence of inexpensive and stable USY zeolite. The yield of EL reached 30.23% at 200 °C for 60 min over the presence of 40% [BSTEA]HSO4 and 60% USY zeolite. Under optimal conditions, the yields of lignin and EL can respectively reach 83.89 and 72.28% of those catalyzed by a fresh catalyst after five cycles. In short, the above-mentioned methods present a green, economic, and efficient route for the extraction of lignin and further treatment of the liquid waste generated during the extraction process.


Subject(s)
Lignin , Zeolites , Lignin/chemistry , Triticum/chemistry , Ethanol/chemistry , Water , Hydrogen , Sulfates
3.
Heliyon ; 7(5): e07057, 2021 May.
Article in English | MEDLINE | ID: mdl-34113728

ABSTRACT

Reversible splenial lesion syndrome (RESLES) is a rare clinico-radiological disorder syndrome with unclear pathophysiology. Here, two sisters with sensorineural deafness as the chief complaint diagnosed with RESLES was reported. Although the sisters had the disease successively, they were divided into two types on imaging by isolated lesions of splenium of the corpus callosum (SCC) and extensive lesions of the corpus callosum. The clinical manifestations and lesions on MRI disappeared after 6 months. The sensorineural deafness of the sisters in this article may be caused by transcallosal auditory pathway (TCAP) injury. Auditory handicap has been found in previous RESLES cases, indicating that we know little about the connection between the SCC and the auditory pathway, and further research is needed.

4.
CJC Open ; 1(4): 209-212, 2019 Jul.
Article in English | MEDLINE | ID: mdl-32159109

ABSTRACT

We report a case with rare signs of subcutaneous hematoma, ecchymoses, and pleural effusion resulting from rupture of a thoracic aneurysm and aortic dissection. An 81-year-old woman had a history of aneurysm for 4 years. Ruptured chronic thoracic aortic dissection was diagnosed in the patient. After 2 weeks of medical therapy, the hematoma in the chest wall was absorbed, the pleural effusion almost disappeared, and the patient's general condition improved. At 6 months follow-up, the patient had no chest discomfort. This case highlights an uncommon sign of ruptured thoracic aneurysm and aortic dissection that clinicians should be aware of.


Nous décrivons un cas où la rupture d'un anévrisme de l'aorte thoracique et une dissection aortique ont été précédés de signes rares, soit un hématome sous-cutané, des ecchymoses et un épanchement pleural. Une femme âgée de 81 ans présentait des antécédents d'anévrisme depuis 4 ans. Cette patiente a reçu le diagnostic de dissection chronique de l'aorte thoracique et de rupture aortique. Après 2 semaines de traitement médical, l'hématome de la paroi thoracique s'était résorbé et l'épanchement pleural était pratique disparu. L'état général de la patiente s'est amélioré. Au suivi à 6 mois, la patiente ne présentait aucune gêne dans la poitrine. Ce cas met en lumière des signes peu courants de la rupture d'un anévrisme de l'aorte thoracique et de dissection aortique dont les cliniciens doivent avoir connaissance.

5.
Zhonghua Liu Xing Bing Xue Za Zhi ; 31(11): 1215-8, 2010 Nov.
Article in Chinese | MEDLINE | ID: mdl-21176678

ABSTRACT

OBJECTIVE: To determine the survival rate of HIV/AIDS patients after receiving free antiretroviral treatment in Dehong prefecture, Yunnan province. METHODS: A retrospective cohort analysis was conducted on all the HIV/AIDS patients aged over 16 years who had started antiretroviral treatment during January 2007 throughout December 2009 in Dehong prefecture. RESULTS: A total of 3103 HIV/AIDS patients had received antiretroviral treatment during the study period. Among them, the mean age was (36.0 ± 9.9) years and 62.4% were males. 66.2% of them were infected with HIV through heterosexual transmission, and the mean treatment follow-up time was 21.7 months. Most patients well complied with the treatment, i.e., the average times of not taking the medicine were less than 5 per month. The cumulative survival rate of antiretroviral treatment after 1, 2, 3, 4, and 5 years were 0.95, 0.94, 0.93, 0.92, and 0.92, respectively. Data from the Cox proportional hazard regression model analysis indicated that, after adjustment for age, gender, and marital status, the baseline CD4(+)T cell counts and transmission route could significantly predicate the rates of survival. Those who were with baseline CD4(+)T cell counts as 200 - 350/mm(3)were less likely to die of AIDS than those with CD4(+) T cell counts < 200/mm(3) (Hazard Ratio or HR = 0.16, 95%CI: 0.09 - 0.28), and HIV-infected through mother-to-child transmission or routes other than heterosexual transmission were less likely to die of AIDS than through injecting drug use (HR = 0.35, 95%CI: 0.13 - 1.00). CONCLUSION: Free antiretroviral treatment had significantly improved the survival of HIV/AIDS patients. Earlier initiation of antiretroviral treatment was likely to have achieved better survival effects.


Subject(s)
Acquired Immunodeficiency Syndrome , HIV Infections , Acquired Immunodeficiency Syndrome/drug therapy , China , HIV Infections/drug therapy , Humans , Retrospective Studies , Survival Analysis
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