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1.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 36(6): 605-610, 2020 Nov.
Artículo en Chino | MEDLINE | ID: mdl-33719267

RESUMEN

Objective: To investigate the effects of Bushen Zhuanggu granule on the expressions of serum growth hormone (GH) and insulin-like growth factor-1(IGF-1) and their receptors in bone tissues of ovariectomized rats. Methods: Forty-eight SD female rats (weight 273±21.3 g) were divided into 4 four groups: the dosage of Bushen Zhuanggu granule group (BSZG) was 2.5 g/(kg·d),the do -sage of estradiol group(E2) was 0.071mg/(kg·d),sham group (SHAM) and ovariectomized model group (OVX group) were given the same amount of saline by oral administration.Each group included 12 rats,the treatments were conducted once a day. After 3 and 6 months of treatment,bone mineral density (B -MD) was measured by bone density instrument;the serum levels of GH and IGF-1 were detected by EL-ISA;the expressions of GHR and IGF-1R of bone tissue were detected by qPCR;the optical density(OD)value and positive cell count of pituitary GH immunohistochemical tablets were analyzed by Image J software,respectively. Results: ①After 3 months intervention,compared with the SHAM, the BMD of the spine in E2 group was increased(P<0.05),and the BMD of both parts in BSZG group were increased(P<0.05).After two stage intervention,BMD of both part in the two drug groups was higher than that in the OVX group(P<0.05).②After two-stage intervention,the expression levels of serum GH and IGF-1,GHR and IGF-1R in BSZG group were higher than those in OVX group (P<0.05).The levels of serum GH and it's receptors in the E2 group were increased (P<0.05), but the serum IGF-1 level remained unchanged (P>0.05) or even was decreased (P<0.05).③After two stage in -tervention,the OD values and the positive cells count in the two drug intervention groups were increased (P>0.05).④Pearson correlation analysis showed that serum GH,IGF-1 concentration and it's receptors in bone tissue were positively related with BMD. Serum GH concentration was positively correlated with OD values and number of positive cells. Conclusion: Bushen Zhuanggu granule can be used to improve the expressions of GH,IGF-1 in serum and its receptors in bone tissues of ovariectomized osteoporosis rats to prevent further loss of bone mass and increase bone mineral density.


Asunto(s)
Hormona del Crecimiento , Factor I del Crecimiento Similar a la Insulina , Animales , Densidad Ósea , Huesos , Medicamentos Herbarios Chinos , Femenino , Humanos , Ovariectomía , Ratas
2.
Sci Total Environ ; 670: 1103-1110, 2019 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-31018426

RESUMEN

Cationic polymers, which are commonly used as flocculants and coagulant aids in water and wastewater treatment, have been recently reported to promote the formation of nitrosamines. Most of the findings to date are based on poly (epichlorohydrin dimethylamine) and poly (diallyldimethylammonium chloride), while few studies have considered nitrosamines formation of polyacrylamides. In this work, the nitrosamines formation from non-ionic, anionic and cationic polyacrylamides was evaluated. Moreover, the effects of chemical structures of cationic polyacrylamides (including molecular weight, charge density, and monomers) on nitrosamines formation were investigated. The results revealed that the highest amount of nitrosamines formation was formed from cationic polyacrylamide, followed by non-ionic polyacrylamide and anionic polyacrylamide. Molecular weight and various cationic monomers showed no significant effects on nitrosamines formation, but monomers generated significantly higher amount of nitrosamines formation than cationic polyacrylamides. Nitrosamines formation increased with the increasing charge density of cationic polyacrylamides, and FTIR analysis results showed that the quaternary amine groups preferentially reacted with chloramines than with amide groups. This work shed new light on the nitrosamines formation from water and wastewater treatment polymers.

3.
R Soc Open Sci ; 5(8): 180025, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30225002

RESUMEN

Poly(diallyldimethylammonium chloride) (polyDADMAC) has been shown to be an important precursor of the probable human carcinogen N-nitrosodimethylamine (NDMA) when in contact with chloramine. In this study, we conducted an orthogonal experiment design to evaluate the effects of pH values, ammonia, bromide, natural organic matter (NOM) and monochloramine dosages on the formation of NDMA from polyDADMAC during chloramination. Meanwhile, single-factor experiments of pH, bromide and NOM prove the results of orthogonal experiment. The results supported that pH was the most critical factor affecting NDMA formation from polyDADMAC during chloramination, and the highest NDMA formation from polyDADMAC occurred at pH near 7 due to released DMA from polyDADMAC degradation and the critical importance of low concentrations of dichloramine in water. In the presence of excess bromide, the NDMA formation was enhanced significantly at all different pH values owing to bromochloramine, which has higher electronegativity of the brominated nitrogen atom than monochloramine or dichloramine. The NDMA formation from polyDADMAC in the presence of NOM was 41.7% lower than NDMA formation in the absence of NOM. The overwhelming majority of NDMA formation from polyDADMAC under simulated conditions was lower than the current advisory levels (i.e. 9 ng l-1 in Ontario, 10 ng l-1 in California).

4.
Huan Jing Ke Xue ; 39(3): 1316-1324, 2018 Mar 08.
Artículo en Chino | MEDLINE | ID: mdl-29965479

RESUMEN

In this study, the effects of magnetic Fe3O4 nanoparticles (Fe3O4 NPs) on soluble microbial products (SMP), loosely bound extracellular polymeric substances (LB-EPS), and tightly bound extracellular polymeric substances (TB-EPS) in anaerobic granular sludge were examined. In addition, the anaerobic granular sludge interior microbial community dynamics were investigated using high-throughput sequencing. The results demonstrated that the removal rate of COD was 83.6% after long-term exposure in the experimental reactor, namely, the anaerobic reactor containing Fe3O4 NPs. It was reduced by 5.7% in comparison with the removal rate in the control reactor. The total amount of TB-EPS in anaerobic granular sludge in the experimental and control reactors was 178.20 mg·g-1 and 138.24 mg·g-1, respectively, while the total amount of SMP in anaerobic granular sludge was 34.88 mg·L-1 and 27.44 mg·L-1, respectively. With regard to the LB-EPS in anaerobic granular sludge in the experimental reactor, the peak of humic acid disappeared and the peak intensity of coenzyme F420 decreased slightly using excitation-emission matrix (EEM) fluorescence spectra. In terms of the microbial community dynamics in the experimental reactor, the abundance of Methanobacterium was greatly augmented from 76.15% to 86.76%; whereas, the abundance of Methanothrix decreased from 17.1% to 7.51%. This indicated that Methanothrix was more sensitive to Fe3O4 NPs. Moreover, the changes in bacterial communities were evident:①the abundance of Proteobacteria dropped from 66.44% to 47.16%; ② the abundance of Actinobacteria grew from 8.97% to 17.33%; and ③ the abundance of Bacteroidetes increased from 8.07% to 17.74%. The increasing abundance of Actinobacteria and Bacteroidetes plays a positive role in the anaerobic hydrolysis of organic matter.


Asunto(s)
Reactores Biológicos/microbiología , Compuestos Ferrosos/química , Nanopartículas del Metal , Aguas del Alcantarillado , Eliminación de Residuos Líquidos , Anaerobiosis , Bacterias , Matriz Extracelular de Sustancias Poliméricas/química , Methanosarcinaceae , Polímeros
5.
Biometals ; 21(6): 665-74, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18587652

RESUMEN

Influence of ladder concentration of nickel (Ni) on the leaves of Hydrocharis dubia were studied after 3 days treatment. The accumulation of Ni, the content of polyamines, proline, malondialdehyde (MDA) and soluble protein, as well as the activities of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) in the leaves were investigated. The result indicated that the toxicity of Ni manifested in respective aspect of physiological and biochemical characters. Significant increase of Ni concentration in the leaf tissue was observed, which was concentration dependent. Visible symptoms of Ni toxicity: chlorosis and necrosis occurred following the 3rd day. Meantime, treatment with Ni resulted in the increase in the generation rate of O2(*-) in the leaves. SOD and CAT activities decreased significantly in response to Ni treatment, it was possibly the reason of accumulation of O2(*-). However, a several-fold decrease in POD activities was found. Our results indicated that because of prolonged increases in O2(*-) level, oxidative damage, measured as the level of lipid peroxidation, occured in the leaves of Ni treated fronds. The changes of the content of polyamines (PAs) were also investigated in the leaves of Hydrocharis dubia. Ni treatment significantly increased the putrescine (Put) level and lowered spermidine (Spd) and spermine (Spm) levels, thereby significantly reducing the ratio of free (Spd + Spm)/Put in leaves, which has been considered as the signal under stress. Although the trend that PS-conjugated PAs and PIS-bound PAs changed the same as free PAs, they changed in more less extent.


Asunto(s)
Hydrocharitaceae/efectos de los fármacos , Níquel/toxicidad , Hojas de la Planta/efectos de los fármacos , Poliaminas/metabolismo , Carotenoides/metabolismo , Catalasa/metabolismo , Clorofila/metabolismo , Hydrocharitaceae/metabolismo , Malondialdehído/metabolismo , Níquel/administración & dosificación , Níquel/metabolismo , Peroxidasa/metabolismo , Hojas de la Planta/metabolismo , Proteínas de Plantas/metabolismo , Prolina/metabolismo , Estrés Fisiológico/fisiología , Superóxido Dismutasa/metabolismo
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