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1.
Ecotoxicol Environ Saf ; 188: 109896, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31704329

RESUMO

Blood is the transmission medium for metal contaminants to and from bodily organs; as such, it can provide useful and reliable information about their bio-kinetics as they're distributed throughout the body. Metals can interact with endogenous proteins present in the blood, and these metal-protein complexes often dictate the fates of the introduced metals. The aim of this study was to investigate cadmium-binding protein characteristics in normal human plasma. Cadmium-binding plasma proteins in two different groups: normal human plasma (n = 29), and normal paired maternal and fetal umbilical cord plasmas (n = 3), were analyzed. In order to detect cadmium-binding plasma proteins present in low concentrations, blood plasma samples were first depleted of their two most abundant proteins - albumin and immunoglobulin G. Both the crude and depleted plasma samples were analyzed using column gel electrophoresis in conjunction with Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). One cadmium-binding protein was detected in 11 of 29 normal plasma samples and all three paired maternal and cord plasma samples. This protein was further identified as apolipoprotein A-I by high-resolution mass spectrometry. To the best of our knowledge, this is the first study to reveal cadmium-binding proteins in real human blood plasma, which is extremely critical to our understanding of cadmium transportation and accumulation in human blood.


Assuntos
Apolipoproteína A-I/sangue , Cádmio/sangue , Poluentes Ambientais/sangue , Sangue Fetal/química , Metalotioneína/sangue , Feminino , Humanos , Limite de Detecção , Espectrometria de Massas , Espectrofotometria Atômica
2.
J Org Chem ; 82(18): 9751-9764, 2017 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-28849930

RESUMO

A series of scarce fulleropyrrolines were synthesized via DMAP-mediated one-step reaction of [60]fullerene with commercially inexpensive aromatic aldehydes and arylmethanamines in the absence or presence of manganese(III) acetate. In the case of aminodiphenylmethane, novel 2,5,5-trisubstituted fulleropyrrolines could be easily obtained without the addition of manganese(III) acetate. As for arylmethanamines without α-substitutions, the addition of manganese(III) acetate was required to suppress the formation of fulleropyrrolidines, in order to generate the desired 2,5-disubstituted fulleropyrrolines. Two tautomers were produced as expected when different aryl groups (Ar1 ≠ Ar2) from aromatic aldehydes and arylmethanamines were employed in the synthesis. A plausible reaction mechanism for the formation of fulleropyrrolines is proposed.

3.
J Org Chem ; 82(16): 8617-8627, 2017 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-28756668

RESUMO

The metal-free-mediated thermal reaction of [60]fullerene with aromatic aldehydes and inactive primary amines bearing electron-donating groups at the α-position afforded a series of 2-aryl-5-alkyl-fulleropyrrolidines, including the scarce 2-aryl-5-benzyl-fulleropyrrolidines as a mixture of cis and trans isomers. With rare exceptions, the mixture of cis and trans isomers could be easily isolated by column chromatography, with a preference of cis isomers as major products. A plausible mechanism for the formation of fulleropyrrolidines is also proposed.

4.
J Org Chem ; 81(19): 9296-9307, 2016 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-27654104

RESUMO

The facile one-step reaction of [60]fullerene with aldehydes and primary amines in the presence of cheap and easily available Cu(OAc)2·H2O afforded a series of new types of fulleropyrrolines with trisubstituted C═C bonds in good to excellent yields, which would be difficult to prepare by known methods. The formed fulleropyrroline under the assistance of Pd(OAc)2 and CuCl2·2H2O could be further converted to 1-fulleropyrrolidine by the chlorohydroxylation reaction of C═C bond. Subsequent elimination reaction of 1-fulleropyrrolidine with the aid of TsOH·H2O generated the scarce 1-fulleropyrroline derivative.

5.
J Org Chem ; 81(17): 7662-74, 2016 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-27471871

RESUMO

Thermal reaction of [60]fullerene with various arylmethanamines in the presence of aromatic aldehydes under air conditions afforded a series of rare 2,5-diaryl fulleropyrrolidines. Intriguingly, the obtained fulleropyrrolidines exhibited different stereoselectivity. N-unsubstituted arylmethanamines exclusively produced 2,5-diaryl fulleropyrrolidines as cis isomers, while N-substituted arylmethanamines with rare exceptions always gave 2,5-diaryl fulleropyrrolidines as trans isomers. Theoretical calculations at the level of B3LYP/6-31G (d,p) were employed to elucidate the stereoselectivity of N-substituted 2,5-diaryl fulleropyrrolidines as trans isomers by investigating the transition-state structures of different cycloaddition pathways.

6.
Exp Ther Med ; 12(2): 895-900, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27446293

RESUMO

The present study aimed to explore the stability, curability and sequelae of cases of Trichloroethylene (TCE) Hypersensitivity Syndrome (THS), and to investigate the causal allergens of THS. Two cases of THS were followed-up in the current study; both cases were healing following glucocorticoid therapy and were discharged >10 weeks prior to follow-up. A questionnaire investigation, health examination and patch test were performed. Allergens of TCE and its metabolites, including chloral hydrate, trichloroethanol (TCOH) and trichloroacetic acid, were applied in the patch test; 4 controls were included. The two subjects were experiencing itching, pigmentation and xerosis of the skin, and had abnormal results in the ophthalmology Schirmer I test and tear break-up time. The body temperature, liver function, superficial lymph nodes, blood, urine routine and autoimmune antibodies of two subjects were shown to be normal, and no new rashes had appeared. All mass concentration of chloral hydrate and TCOH were positive; 5.0% trichloroacetic acid was weakly positive, 0.5% trichloroacetic acid and all mass concentration of TCE were negative. All patch tests were negative in the 4 control subjects. The results suggest that THS was stable following treatment with glucocorticoid therapy. Dry eye syndrome may continue as a sequelae of THS. The patch test demonstrated that the mechanism underlying THS is delayed-type hypersensitivity induced by TCE. In addition, as the hypersensitivity state in a THS rehabilitee could be sustained over a long period of time, it suggests that the metabolites of TCE, not TCE itself, are responsible for THS. Therefore, patients with THS should avoid contact with TCE and its metabolites, and avoid using hypnotic and anticonvulsive drugs containing chloral hydra as the primary ingredient.

7.
Org Biomol Chem ; 10(43): 8720-9, 2012 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-23037937

RESUMO

Thermal reactions of [60]fullerene with a series of amino acids and amino acid esters under aerobic and dark conditions have been investigated. Fulleropyrrolidines can be obtained from these reactions although an aldehyde is not added purposely. Possible reaction mechanisms involving uncommon C-N bond cleavages have been proposed to generate aldehydes, which then react with amino acids and amino acid esters to provide azomethine ylides, followed by 1,3-dipolar cycloaddition to [60]fullerene affording fulleropyrrolidines. Control experiments support our proposed mechanisms, and elucidate the innate nature of C-N bond cleavages of amino acids and amino acid esters.


Assuntos
Aminoácidos/química , Ésteres/química , Fulerenos/química , Temperatura , Estrutura Molecular
8.
Artigo em Chinês | MEDLINE | ID: mdl-22804938

RESUMO

OBJECTIVE: To explore the mechanism of occupational medicamentosa-like dermatitis (OMDT) induced by trichloroethylene (TCE) and some immunity indexes in workers occupationally exposed to TCE. METHODS: The blood samples from 8 cases with medicamentosa-like dermatitis in 1st, 2nd, 3rd, 4th and 5th weeks after admitting to hospital were examined for liver function, immunoglobulin and some complement indexes. Thirty nine workers occupationally exposed to TCE were investigated for urinary TCE and some immuno-complement indexes. The TCE concentrations of air in workplaces were monitored. RESULTS: C3d-CIC and C3 of patients before admission were (92.86 ± 44.80) mg/L and 0.91 ± 0.19 mg/L, respectively. C3d-CIC and C3 of patients before discharge were (52.41 ± 17.75) mg/L and (1.14 ± 0.22) mg/L, respectively. There were significant differences between admission and discharge (P < 0.05). The average TCE concentration in 4 workplaces was (351.96 ± 36.72) mg/m(3), which was higher than the occupational exposure limits (OELs). The number of workers exposed to the TCE concentration-time weighted and TCA in urine over OELs were 28.21% and 56.41% of total subjects, respectively. The serum IgG and CIC levels of patients before discharge were (10.03 ± 1.21) mg/L and 103.50 ± 29.17 mU/L, which were significantly lower than those (17.21 ± 1.85) mg/L and (227.46 ± 111.67) mU/L of patients before admission (P < 0.01). CONCLUSION: The type II and III hypersensitivity may be associated with OMDT and the organ injure induced by TCE.


Assuntos
Proteínas do Sistema Complemento/imunologia , Dermatite Ocupacional/imunologia , Exposição Ocupacional , Tricloroetileno/toxicidade , Adolescente , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
9.
J Org Chem ; 74(20): 7743-9, 2009 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-19761269

RESUMO

The manganese(III) acetate-mediated radical reaction of [60]fullerene with carboxylic acids in the presence of 4-(dimethylamino)pyridine exclusively afforded the [60]fullerene-fused lactones. Interestingly, the lead(IV) acetate-promoted radical reaction of [60]fullerene with the same carboxylic acids selectively gave another type of fullerene products, i.e., fullerenyl esters. Possible mechanisms for the formation of fullerene products are proposed.

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