RESUMO
An Fe(II) SCO complex based on an acylhydrazone ligand with an amino functional group has been prepared. The complex is able to dissociate and regather upon protonation and deprotonation, in both solid state and solution, accompanied by spin state switching, marked change of color, and distinct solubility in water. Moreover, the complex shows distinct magnetic responses toward formaldehyde and protic and nonprotic solvents, as a result of the different affinity of the amino functional site with those chemicals.
RESUMO
A mononuclear FeII complex that shows a high-spin (S=2) paramagnetic behavior at all temperatures (with standard temperature-scan rates, ≈1â K min-1 ) has, in fact, a low-spin (S=0) ground state below 100â K. This low-spin state is not easily accessible due to the extremely slow dynamics of the spin-crossover process-a full relaxation from the metastable high-spin state to the low-spin ground state takes more than 5â h below 80â K. Bidirectional photo-switching of the FeII state is achieved reproducibly by two selective irradiations (at 530-590 and 830-850â nm). The slow dynamics of the spin-crossover and the strong structural cooperativity result in a remarkably wide 95-K hysteresis loop induced by both temperature and selected light stimuli.
RESUMO
OBJECTIVE: To compare PPD conversion with γ-interferon release assay (IGRA) in determining the newly Mycobacterium tuberculosis (MTB) infection during a TB outbreak. METHODS: The 505 subjects exposed to a TB outbreak were divided into 3 groups based upon the induration diameters of PPD before the outbreak. The changes of PPD induration diameters were observed in different groups, and correlation between PPD conversion or IGRA and exposure levels were analyzed by logistic regression. RESULTS: In subjects with the highest exposure level, the increase in induration of PPD was (12 ± 5) mm, (7 ± 4) mm, and (5 ± 3) mm respectively among the previous PPD < 5 mm, 5 - < 10 mm, and ≥ 10 mm groups, the difference being significant among groups, χ(2) = 43.12, P < 0.01. Using logistic regression analysis, PPD conversion was related to the exposure level (OR = 4.70, P < 0.05) only in the PPD < 5 mm group, while IGRA positivity was closely related to the exposure levels in all 3 groups (OR values were 2.16 - 3.60, P < 0.05). In the high exposure group, the subjects with IGRA positivity combined with PPD conversion rate was 26.1% (31/119), and the subjects with IGRA positivity but no PPD conversion rate was 39.5% (47/119), while in the low exposure group the results were 6.5% (12/185) and 16.8% (31/185) respectively, the difference being significant (χ(2) = 22.82 and 19.63, P < 0.01). After 1 year of follow-up, the reversion rate of the subjects with IGRA positivity was 48.1% (91/189), while the mean increase value of PPD was (1.1 ± 4.0) mm. CONCLUSION: IGRA is superior to PPD conversion in the diagnosis of tuberculosis infection, and more valuable in the detection of newly infected cases.
Assuntos
Surtos de Doenças , Testes de Liberação de Interferon-gama , Teste Tuberculínico , Tuberculose/diagnóstico , Feminino , Humanos , Modelos Logísticos , Masculino , Adulto JovemRESUMO
The phenolic compounds composition, antioxidant and antidiabetic properties of eight brown sorghum genotypes were investigated. DPPH radical scavenging activity was highest in SOR 03, followed by SOR 11, SOR 08 and SOR 33. SOR 33, SOR 03, SOR 08, SOR 11 showed the highest ABTS radical scavenging activity. Furthermore, SOR 11, SOR 17 and SOR 33 exhibited significantly higher percentage inhibitory activity of α-glucosidase and α-amylase (IC50 = 14.71, 32.98, 24.93 µg/ml and 27.6, 23.84, 45.01 µg/ml, respectively) compared to acarbose (IC50 = 59.34 and 27.73 µg/ml, respectively). Similarly, SOR 17, SOR 11 and SOR 33 showed significantly potent inhibition of AGEs formation with IC50 values of 14.19, 18.23 and 26.31 µg/ml, respectively, compared to aminoguanidine (AG) (52.30 µg/ml). Flavones, isoflavones and dihydroflavonols were the predominant flavonoids identified in SOR 11, SOR 17 and SOR 33 genotypes. Therefore, these sorghum grains are potential candidates for the development of functional foods.
Assuntos
Antioxidantes/análise , Flavonoides/análise , Hipoglicemiantes/análise , Sorghum/química , alfa-Amilases/antagonistas & inibidores , alfa-Glucosidases , Acarbose/farmacologia , Cromatografia Líquida de Alta Pressão , Grão Comestível/química , Flavonoides/farmacologia , Inibidores de Glicosídeo Hidrolases , Fenóis/análise , Fenóis/farmacologia , Espectrometria de Massas em TandemRESUMO
A new donor-acceptor Stenhouse adduct based on a N,N,N'-trimethylethylenediamine donor has been reported. An unprecedented isomer has been isolated, and rich conversions between three isomers have been achieved upon visible-light irradiation or base/acid stimuli. The drastic color change associated with structural conversion has been utilized to selectively sense volatile primary amines as well as high-charged hard Lewis acids (Sc3+, Ti4+, Cr3+, and Al3+).
RESUMO
Many genes of industrial relevance can be found in soil. In this study, metagenome sequencing of paddy soil was performed with 55.68 Gb sequences and 1,787,113 putative open reading frames (ORFs). The functional profiles and metabolic pathway of soil metagenomes were examined using Gene Ontology, Metagenomics RAST, and Kyoto Encyclopedia of Genes and Genomes. To verify the protein function and assembly of ORFs, a putative gene encoding α-galactosidase, namely GalR, which shares 65% identity with an unpublished glycoside hydrolase (GH) 27 family protein, was synthesized using its optimal codon for overexpression in Escherichia coli. GalR was successfully obtained and characterized. The optimal temperature and pH for GalR activity were 30°C and pH 9, respectively. Enzymatic activity indicated that GalR was alkaliphilic and different from acidophilic α-galactosidase in the GH 27 family. Furthermore, 50% of the relative activity of GalR can be attained for 1.7 and 0.7 h preincubation at 40°C and 50°C, respectively. Significant inhibition of GalR was observed in the presence of ethylenediaminetetraacetic acid (EDTA), MgCl2, sodium dodecyl sulfate (SDS), and H2O2; however, it was resistant to 0.1% methanol and ethanol and was slightly activated with NaCl and KCl. The specific activity of GalR was achieved at 11.6 and 0.59 µmol/min/mg of protein using p-nitrophenyl-α-d-galactopyranoside and raffinose as substrates, respectively. Consequently, the metagenomic sequencing-based strategy can provide information for mining novel genes.
Assuntos
Genes Sintéticos , Metagenoma , Metagenômica/métodos , Solo/química , alfa-Galactosidase/genética , alfa-Galactosidase/isolamento & purificação , Clonagem Molecular , Escherichia coli/genética , Galactose/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Peróxido de Hidrogênio , Fases de Leitura Aberta , Rafinose/metabolismo , Sesbania/genética , Microbiologia do Solo , Trifolium/genéticaRESUMO
OBJECTIVE: To study the difference of plasma actual bicarbonate between the children with growth hormone deficiency (GHD) and idopathatic short stature (ISS) and to value the plasma bicarbonate standard deviation scores (SDS) in diagnosis of GHD. METHODS: Forty-seven short stature children were divided into two groups (GHD and ISS) according to the peak GH response to provocative test. Plasma actual bicarbonate concentrations anion gap (AG), base excess and electrolytes were measured in 47 children with short stature before GH provocative tests. RESULTS: The mean plasma actual bicarbonate concentrations, bicarbonate SDS were (22.60+/-1.29)mmol/L and -0.27+/-0.98 respectively in GHD children, which were significantly lower than those of ISS children (P<0.01), whereas AG was higher than that of ISS children [(11.73+/-4.52 vs 7.87+/-1.70) mmol/L], P<0.01. Seventy-two percent of patients with bicarbonate SDSAssuntos
Equilíbrio Ácido-Base
, Transtornos do Crescimento/metabolismo
, Hormônio do Crescimento Humano/deficiência
, Adolescente
, Bicarbonatos/sangue
, Criança
, Pré-Escolar
, Feminino
, Humanos
, Masculino