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1.
Anal Chem ; 96(8): 3470-3479, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38336002

RESUMO

A self-powered photoelectrochemical (PEC) sensor has attracted widespread attention in the field of analysis, but it is still a challenge to enhance its response signals with rational strategies. In this work, a novel self-powered PEC sensing platform was developed for the quantitative detection of gatifloxacin (GAT) based on a photofuel cell consisting of two types of ZIF-derived ZnO/Co3O4 heterojunctions as photoactive materials. Peroxymonosulfate (PMS) was first used as an electron acceptor coupled with a photofuel cell to develop a synergetic signal amplification strategy. In a dual-photoelectrode system, the PMS activation on the ZnO@Co3O4 photocathode not only accelerated electron transfer from the Co3O4@ZnO photoanode to achieve strong signal intensity but also improved the sensing sensitivity by the oxidation reaction of generated highly active radicals to GAT. Compared with the absence of electron acceptors, the introduction of PMS produced a 2-fold enhancement in the signal output performance and a more than 72-fold improvement in the signal sensitivity. For the construction of the sensing interface, a molecularly imprinted polymer was assembled on the photocathode to specifically recognize GAT. The proposed sensor exhibited a detection range of 10-1 to 105 pM with a detection limit of 0.065 pM. The proposed sensing method has the advantages of sensitivity, simplicity, reliable stability, and anti-interference ability, which opens the door to the design of high-performance self-powered PEC sensors.


Assuntos
Técnicas Biossensoriais , Cobalto , Óxidos , Peróxidos , Óxido de Zinco , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Limite de Detecção
2.
J Hazard Mater ; 460: 132473, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37683348

RESUMO

The extensive utilization of neonicotinoid insecticides (NNIs) in agricultural practices ultimately poses a significant threat to both the environment and human health. This work focuses on the efficient degradation and detoxification of the representative NNI, thiamethoxam (THX), and explores the underlying mechanism using a Co-Fe-Mn mixed spinel doped carbon composite catalyst activated persulfate. The findings demonstrate that the composite effectively degrades THX, achieving a degradation rate of 95% in 30 mins, while requiring only a fraction (one-sixteenth) of the oxidant dosage compared to pure carbon. The study aimed to examine the negative impact of reactive halogens on reactive oxygen species within a saline environment. The degradation byproducts were linked to the presence of two common electron-withdrawing groups, namely halogens and nitro in the THX molecule. It was hypothesized that the degradation process was primarily influenced by C-N bond breaking and hydroxylation occurring between the diazine oxide and 2-chlorothiazole rings. Consequently, dehalogenation and carbonylation processes facilitated the elimination of halogenated components and pharmacophores from the THX, leading to detoxification. In addition to the identified free radical pathway including SO4•-, •OH and O2•- contributed to THX degradation, the participation of non-radical pathways (1O2 and electron transfer) were also confirmed. The efficacy of detoxification was further validated through toxicity assessment, employing quantitative conformation relationship prediction and microbial culture utilizing Bacillus subtilis.


Assuntos
Inseticidas , Humanos , Tiametoxam , Carbono , Halogênios
3.
Sci Total Environ ; 885: 163844, 2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37142005

RESUMO

A field experiment was conducted to investigate the effectiveness and mechanisms of foliar spraying of transpiration inhibitor (TI) and different amounts of rhamnolipid (Rh) on the Cd content in rice grain. The contact angle of TI on the rice leaves was significantly reduced when it was combined with one critical micelle concentration of Rh. The Cd concentration in the rice grain in the presence of TI, TI + 0.5Rh, TI + 1Rh, and TI + 2Rh significantly decreased by 30.8 %, 41.7 %, 49.4 %, and 37.7 % respectively, compared with the control treatment. Specifically, the Cd content with TI + 1Rh was as low as 0.182 ± 0.009 mg/kg, which meets the national food safety requirements (< 0.2 mg/kg). The rice yield and plant biomass of TI + 1Rh were highest compared to the other treatments, possibly because of the alleviation of oxidative stress due to Cd. The hydroxyl and carboxyl concentrations in the soluble components in the leaf cells for the TI + 1Rh treatment were the highest compared to the other treatments. Our results demonstrated that the foliar spraying of TI + 1Rh is an efficient method to reduce Cd accumulation in rice grain. It holds potential for the future development of safe food production in soils polluted with Cd.


Assuntos
Oryza , Poluentes do Solo , Cádmio/toxicidade , Cádmio/análise , Poluentes do Solo/toxicidade , Poluentes do Solo/análise , Solo
4.
Clin Rheumatol ; 42(1): 101-109, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36155871

RESUMO

OBJECTIVE: To investigate the clinical features and potential associated risk factors of Epstein-Barr virus (EBV) DNA positivity in systemic lupus erythematosus (SLE) patients. METHODS: A total of 121 newly diagnosed SLE patients who had never used immunosuppressive drugs (treatment-naïve) and 191 previously treated SLE patients from January 2017 to January 2020 were enrolled in this study. And 115 age- and sex-matched non-rheumatic disease controls were also included. RESULTS: A significantly higher incidence of EBV DNA positivity and higher viral DNA copies in peripheral blood mononuclear cells were observed among treatment-naïve and previously treated SLE patients compared with controls. The positivity rate of EBV DNA was further increased in previously treated SLE patients compared with that in treatment-naïve patients. EBV DNA-positive treatment-naïve SLE patients presented lower incidence of hemolytic anemia and more affected organ number than EBV DNA-negative patients. EBV DNA-positive treated SLE patients showed older age, longer immunosuppressive duration, higher IgG level, and higher Th/Ts ratio than EBV DNA-negative patients. Patients responding well to treatment with decreased SLE disease activity index scores had a transformation of EBV DNA from positive to negative in treated SLE patients. Multivariate logistic regression analysis showed that older age, higher IgG level, and longer immunosuppressive duration were associated risk factors for EBV DNA positivity in SLE patients, while higher TNF-α level was a protective factor. CONCLUSION: Older age, higher IgG level, and longer immunosuppressive duration are associated with the positivity of EBV DNA in SLE patients. A seroconversion of EBV DNA indicates an association between EBV positivity and therapy response, while larger number cases are needed to confirm. Key Points • Older age, higher IgG level, and longer immunosuppressive duration are associated with EBV DNA positivity in SLE patients. • A seroconversion of EBV DNA might be an indicator to reflect the SLE therapy -response.


Assuntos
Infecções por Vírus Epstein-Barr , Lúpus Eritematoso Sistêmico , Humanos , Herpesvirus Humano 4/genética , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/epidemiologia , Leucócitos Mononucleares , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Fatores de Risco , Imunoglobulina G , Anticorpos Antivirais
5.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-988514

RESUMO

Objective @#To investigate and analyze the root and root canal morphology of mandibular first molars (MFMs) in the Tibetan population using cone-beam computed tomography (CBCT) and to provide references for clinical root canal treatment in the Tibetan population. @*Methods@#This study was reviewed and approved by the Ethics Committee, and informed consent was obtained from the patients. CBCT imaging data of 300 mandibular first molars from 300 Tibetan patients were included. Patient age, the number of roots in mandibular first molars were recorded. The morphology and incidence of mesial root and mesial root canals and the morphology and incidence of distal root and distal root canals were statistically analyzed by Vertucci classification. @*Results @#There were 198 double-root teeth and 102 three-root teeth in the 300 mandibular first permanent molars. Among the three-rooted molars, 1 case had mesiolingual roots, and the rest had distolingual roots. The incidence rate of the distolingual root was 33.7%(101/300). The most common root canal configuration was Vertucci Ⅳ 65.7% (197/300), followed by Vertucci Ⅱ 20.3% (61/300) in the mesial roots. The overall incidence of middle mesial canals (MMCs) was 6% (18/300), with the highest incidence of MMCs in the 20-40 year-old group at 9% (9/100). The distal roots canals of single-distal-rooted mandibular first molars were mainly Vertucci Ⅰ 66.8% (133/199), followed by Vertucci Ⅱ 14.6% (29/199) and Vertucci Ⅳ 11.6% (23/199). For the mandibular first permanent molars with two distal roots, 96% (97/101) of the distal buccal roots and 100% (101/101) of the distal lingual roots were Vertucci Ⅰ root canals. @*Conclusion@# The root and root canal morphology of mandibular first permanent molars in a Tibetan population is complex and variable. Approximately one-third of patients have distolingual roots, and clinicians should carefully explore the root canals under the guidance of CBCT.

6.
Bioresour Technol ; 364: 128094, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36220530

RESUMO

Direct production of 5-hydroxymethylfurfural (HMF) through biomass always needs the addition of exogenous catalysts and causes extra costs. Herein, acid mine drainage (AMD), one of the traditional wastewaters, was introduced as a natural catalyst to produce HMF directly from lignocellulosic biomass. Key factors in the biomass conversion were optimized and investigated by the response surface methodology (RSM), and the HMF yield reached 13.51 wt% under optimal conditions. The metal elements and the acidic environment in AMD activated the Fenton reaction to effectively destroy the lignocellulose structure and synergistically promote the formation of HMF. Furthermore, the biomass substrate in the biomass conversion was indirectly modified by the AMD during this process. The biomass conversion residue could be prepared by pyrolysis to obtain a functional metal-loaded carbon material with good adsorption of thiamethoxam (THX), which provides a sustainable solution for the disposal of biomass conversion residue.

7.
Sci Total Environ ; 831: 155393, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35461937

RESUMO

BACKGROUND: Living near green spaces may benefit various health outcomes. However, no studies have investigated the greenness-bone linkage in the general population. Moreover, to which extent ambient air pollution (AAP), physical activity (PA), and body mass index (BMI) mediate this relationship remains unclear. We aimed to explore the association between greenness and bone strength and the potential mediating roles of AAP, PA, and BMI in Chinese adults. METHODS: This cross-sectional analysis enrolled 66,053 adults from the China Multi-Ethnic Cohort in 2018-2019. The normalized difference vegetation index (NDVI) and enhanced vegetation index (EVI) were employed to define residential greenness. The calcaneus quantitative ultrasound index (QUI) was used to indicate bone strength. Multiple linear regression models and mediation analyses were used to estimate the residential greenness-bone strength association and potential pathways operating through AAP (represented by PM2.5 [particulate matter <2.5 µm in diameter]), PA, and BMI. Stratification analyses were performed to identify susceptible populations. RESULTS: Higher residential exposure to greenness was significantly associated with an increase in QUI, with changes (95% confidence interval) of 3.28 (3.05, 3.50), 3.57 (3.34, 3.80), 2.68 (2.46, 2.90), and 2.93 (2.71, 3.15) for every interquartile range increase in NDVI500m, NDVI1000m, EVI500m, and EVI1000m, respectively. Sex, urbanicity, annual family income, smoking, and drinking significantly modified the association of greenness-bone strength, with more remarkable associations in males, urban residents, subjects from wealthier families, smokers, and drinkers. For the NDVI500m/EVI500m-QUI relationship, the positive mediating roles of PM2.5 and PA were 6.70%/8.50 and 2.43%/2.69%, respectively, whereas those negative for BMI and PA-BMI were 0.88%/1.06% and 0.05%/0.05%, respectively. CONCLUSION: Living in a greener area may predict higher bone strength, particularly among males, urban residents, wealthier people, smokers, and drinkers. AAP, PA, BMI, and other factors may partially mediate the positive association. Our findings underscore the importance of optimizing greenness planning and management policies.


Assuntos
Poluição do Ar , Adulto , Poluição do Ar/análise , Índice de Massa Corporal , China/epidemiologia , Estudos Transversais , Humanos , Masculino , Material Particulado/análise
8.
Sci Total Environ ; 822: 153426, 2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35090917

RESUMO

With the rapid depletion of fossil energy and increasingly severe environmental pollution, the development of biomass resources for biorefineries has become a new research focus. However, heavy metals may be released during the thermochemical treatment when the biomass materials used in biomass conversion are contaminated by heavy metals. This can cause secondary environmental pollution or transference to the target products, reducing product quality. Therefore, having a systematic understanding of the fate of heavy metals in biomass conversion is necessary for alleviating potential risks. This study presents the current status of contaminated biomass and conversion products involving thermochemical processes, the migration, transformation, and impact of heavy metals in biomass conversion was investigated, and the utilization of heavy metals in contaminated biomass was briefly outlined. This review aims to link biomass conversion to the fate of heavy metals, avoid existing risks as much as possible to produce cleaner products efficiently, and promote the sustainable development of heavy metal contaminated biomass resources.


Assuntos
Metais Pesados , Biomassa , Poluição Ambiental , Metais Pesados/análise
9.
Bioresour Technol ; 337: 125421, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34153866

RESUMO

In recent years, 2, 5-furandicarboxylic acid (FDCA) has attracted much attention as the precursor of bio-polyester materials. A coupled process of ultrasonic-assisted dilute acid pretreatment and MnO2 was designed in this study to directly produce FDCA from lignocellulosic biomass, which is different from the traditional preparation process. Moreover, the critical parameters in the process were analyzed and optimized by the response surface method. The yield of FDCA could reach 52.1% under the optimal conditions. The reaction mechanism indicated that heavy metal elements in lignocellulosic biomass could play the role of the Lewis acid catalyst to promote the formation of FDCA to a certain extent. With the increase of temperature, the heavy metals transfer in biomass from the solid phase to the liquid phase increased, but most of them remain in the former. Therefore, further purification and treatment measures are worthy of attention.


Assuntos
Compostos de Manganês , Óxidos , Biomassa , Catálise , Ácidos Dicarboxílicos , Furaldeído , Furanos , Ultrassom
10.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-909586

RESUMO

OBJECTIVE To investigate whether Renqing Changjue has a protective effect on acute respiratory dis?tress syndrome (ARDS) induced by endotoxin lipopolysaccharide (LPS) in rabbits. METHODS Thirty-six healthy male New Zealand white rabbits were randomly divided into six groups: normal control group, model group, dexamethasone group, Renqing Changjue high, middle and low dose group, with six rabbits in each group. LPS was used to replicate the ARDS model after five consecutive days of gavage. Arterial pressure, respiratory rate and anal temperature blood were recorded for arterial blood gas analysis at 0, 0.5, 1, 2 and 4 h, respectively. At the end of the four-hour experiment, rab?bits were killed by bloodletting, and the lung tissue was quickly removed to determine the cytokines, SOD, MDA and pathological examination of rabbit lung. RESULTS Renqing Changjue can significantly reduce the pathological changes of lung in ARDS model group. The expression of AQP1 and MPO in rabbit lung was significantly decreased by immuno?histochemistry (P<0.05) ,reduce the lung wet/dry weight ratio, increase the ratio of PaO2/FiO2, inhibit the release of inflammatory factors and scavenge free radicals and antioxidant effects. CONCLUSION Renqing Changjue can effec?tively protect rabbits with acute respiratory distress syndrome induced by LPS, and may protect the lung by inhibiting the release of cytokines and anti-oxidation.

11.
Animals (Basel) ; 10(3)2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32121109

RESUMO

The objective of this study was to probe into the polymorphism of Y-STR INRA189 and identify the geographical distribution pattern of its alleles in the Chinese domestic yak gene pool. We examined the variation at INRA189 locus in 682 male yaks representing 15 breeds/populations in China. The results showed that six alleles, including five reported previously (149, 155, 157, 159, and 161 bp) and a new one identified in this study (139 bp), were detected at INRA189 locus based on genotyping analysis. The frequencies of six alleles varied among the 15 yak breeds/populations with a clear phylogeographical pattern, which revealed the paternal genetic difference among Chinese yak breeds/populations. The average polymorphism information content (PIC) among 15 yak domestic breeds/populations was 0.32, indicating INRA189 to be an intermediate polymorphic Y-STR marker (0.25 < PIC < 0.5) in yak. Sequence alignment revealed that the variations among six alleles at INRA189 were defined by a TG dinucleotide repeat motif, which repeated for 12, 17, 20, 21, 22, and 23 times, corresponding to the alleles of 139, 149, 155, 157, 159, and 161 bp, respectively. Therefore, we believe that the polymorphic yak Y-STR INRA189 can be used to characterize male-mediated genetic events, including paternal genetic origin, diversity, and evolution.

12.
PLoS One ; 12(9): e0185048, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28915257

RESUMO

From April to November 2016, two outbreaks of epidemic keratoconjunctivitis (EKC) occurred successively at primary and middle schools in the Tibet Autonomous Region of China, and a total of 197 clinically diagnosed cases were reported. Real-time PCR analyses confirmed that human adenovirus (HAdV) infection was related to these outbreaks. Further studies involving sequence determination and phylogenetic analysis based on the penton base, hexon, and fiber genes indicated that human adenovirus type 8 (HAdV-8), belonging to species D, was responsible for the outbreaks. This is the first report of a HAdV-8 associated EKC outbreak in mainland of China, and the results of this study are expected to provide support for future research into HAdV-8 in China.


Assuntos
Infecções por Adenovirus Humanos/epidemiologia , Adenovírus Humanos , Conjuntivite Viral , Surtos de Doenças , Linhagem Celular , Conjuntivite Viral/epidemiologia , Conjuntivite Viral/virologia , Feminino , Humanos , Masculino , Tibet/epidemiologia
13.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-668196

RESUMO

[Objective]To investigate the effects of dietary curcumin on the prevention and treatment of allergic airway inflamma?tion in young mice for simulating the allergic airway inflammation of 3-12 years old children.[Methods]The 4 weeks young female BALB/c mice were randomly divided into three groups (n=8): Control group, Model group and curcumin group (800 mg curcumin/ kg diet). 24 h after the last OVA challenge, the symptoms of mice in each group were observed, the inflammatory cells in the bronchoalve?olar lavage fluid (BALF) were measured, various kinds of blood cells were detected, the inflammatory cells around the peribronchial ar?eas stained by H&E and the goblet cell hyperplasia in the lungs stained by PAS were analyzed. Additionally, the IL-4, IL-5, IL-13 in the BALF and the total IgE level in the plasma were detected by ELISA, and the activation of p38 MAPK and AKT was measured by western blot.[Results]The mice of model group showed the symptoms of allergic airway inflammation, such as repeatedly scratched the noses, showed nodding breath, notably, the weight of model mice was decreased significantly during the OVA challenge phase, while the symptoms mentioned above were alleviated in curcurmin group. The blood cells test found that the curcumin could in?hibit the elevation of the eosinophils significantly (P<0.05). Dietary curcumin treatment significantly decreased the inflammatory cells in the BALF and peribronchial areas, and the IL-4, IL-5, IL-13 levels in the BALF were significantly inhibited (P<0.05). The goblet cell hyperplasia was attenuated by curcumin treatment, and the dietary curcumin inhibited the activation of p38 MAPK and AKT sig?naling.[Conclusions]Dietary curcumin can alleviate the allergic airway inflammation of young mice, which may through inhibiting the transduction of p-38 MAPK and AKT signaling.

14.
J Pediatr Endocrinol Metab ; 28(1-2): 87-92, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25153215

RESUMO

OBJECTIVE: We aimed to obtain the fat base value and the fat distribution characteristics of Tibetan children and teenagers by estimating their body fat content with the bioelectrical impedance method. METHODS: We recruited 1427 healthy children and teenagers by a stratified cluster sampling method. By using bioelectrical impedance analysis, we obtained various values relevant to fat. RESULTS: We found that total body fat mass and the fat mass of various body parts increased with age in boys and girls. Yet there were no differences between age groups until 11 years. However, fat mass increased quickly between 11 and 18 years, and significant differences were seen between adolescent boys and girls; all fat indices were higher in girls than in boys (p<0.05). CONCLUSIONS: The characteristics of fat in Tibetan children and teenagers in Tibet is related to age and gender related hormone secretion, which reflects the physiological characteristics in different developmental stages.


Assuntos
Tecido Adiposo/anatomia & histologia , Distribuição da Gordura Corporal , Adolescente , Adulto , Fatores Etários , Distribuição da Gordura Corporal/estatística & dados numéricos , Criança , Desenvolvimento Infantil/fisiologia , Impedância Elétrica , Feminino , Humanos , Masculino , Tamanho do Órgão , Fatores Sexuais , Tibet/epidemiologia , Adulto Jovem
15.
Sheng Li Xue Bao ; 63(2): 143-8, 2011 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-21505729

RESUMO

The aim of this study was to investigate the effect of integripetal rhodiola herb on pulmonary arterial remodeling and expression of vascular endothelial growth factor (VEGF) in high altitude pulmonary hypertension in rats. Fifty healthy male Wistar rats were divided into five groups randomly: Plain control group (LC group), 10-day plateau group (H(10) group), 30-day plateau group (H(30) group), 10-day rhodiola-treated plateau group (R(10) group), and 30-day rhodiola-treated plateau group (R(30) group). Each group included 10 rats. The rats in LC group were kept in Chengdu (500 meters above sea level), and rats in H and R groups were kept in Lhasa (3 700 meters above sea level). The rats in R group were daily treated with integripetal rhodiola herb extract (24%, 10 mL/kg) intragastrically for 10 d or 30 d, while rats in LC and H groups were treated with the same volume of saline. Mean pulmonary arterial pressure (mPAP) was detected via a catheter in the pulmonary artery by pressure waveform monitoring. The ratio value of right ventricle weight to left ventricle plus septum weight [RV/(LV + S)] was measured. The microstructure of pulmonary arterioles was examined by electron microscopy. The expression of VEGF in the lung was investigated using immunohistochemistry. The results showed that mPAP and [RV/(LV + S)] in H(10) group and H(30) group were higher than those in LC group (P < 0.05); but there was no significant difference between H(10) group and R(10) group (P < 0.05); and mPAP and [RV/(LV + S)] in H(30) group were lower than those in H(30) group (P < 0.05). Electron microscopy showed that compared to LC group, arteriolar endothelial cells were arranged in a columnar or palisading form, protruding into the lumen, accompanied with luminal stenosis, irregular internal elastic membrane, and proliferation of vascular smooth muscle cells in H groups, which was more obvious in H(30) group than in H(10) group; while these pathological changes were attenuated in the R groups compared to H groups. The levels of VEGF protein in H groups were also higher than those in LC group (P < 0.05); while the expression of VEGF in R(30) group was lower than that in H(30) group. In summary, the results show that the integripetal rhodiola herb can attenuate high altitude-induced pulmonary arterial remodeling in rats, and the inhibition of VEGF protein expression by rhodiola may be one of the mechanisms.


Assuntos
Altitude , Medicamentos de Ervas Chinesas/farmacologia , Hipertensão Pulmonar/fisiopatologia , Artéria Pulmonar/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Doença da Altitude/prevenção & controle , Animais , Arteríolas/metabolismo , Arteríolas/patologia , Hipertensão Pulmonar/metabolismo , Hipertensão Pulmonar/patologia , Masculino , Artéria Pulmonar/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Rhodiola
16.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-242929

RESUMO

<p><b>OBJECTIVE</b>To observe the color changes of nickel-titanium (Ni-Ti) orthodontic wires induced by fluoride.</p><p><b>METHODS</b>Each 40 samples of 4 kinds of nickel-titanium orthodontic wires (IMD, SL, TP, YY) were put into artificial saliva with sodium fluoride at different F concentrations (0.05%, 0.10%, 0.15%) and artificial saliva, separately. Dislodged the species and immersed them into artificial saliva with sodium fluoride for 3 minutes, then washed them with deionized water, and put back to artificial saliva, this course should be repeated 3 times per day. The whole immersion test lasted for 28 days. The color and micro-morphous changing were observed.</p><p><b>RESULTS</b>The color changes came to be more serious as the F- concentration growing (P < 0.05). At the same F- concentration, the color changes of IMD and YY were higher than SL and YP (P < 0.01), while there were no significant difference between IMD and YY, SL and TP (P > 0.05).</p><p><b>CONCLUSION</b>Fluoride can change the color of Ni-Ti wire. Different Ni-Ti wires get different changes at the same F- concentration.</p>


Assuntos
Ligas Dentárias , Fluoretos , Níquel , Fios Ortodônticos , Fosfatos , Saliva Artificial , Fluoreto de Sódio , Titânio
17.
Sheng Li Xue Bao ; 60(4): 541-6, 2008 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-18690398

RESUMO

The aim of the present study is to investigate the effect of progesterone-induced expression of cyclin G1 on the proliferation of endometrial epithelial cells. To obtain mouse endometrial epithelial cells, the uteri were isolated from ovariectomized mice which were injected subcutaneously with 100 ng estradiol per day for two days. Then the uteri were digested by dispase and pancreatin respectively. Endometrial epithelial cells were cultured in DMEM/F12 containing 6% fetal bovine serum, and divided into four groups when they grew to confluence. Each of the groups was treated as follows: Group E was treated with 0.01 micromol/L estradiol only, group P was treated with 1 micromol/L progesterone, group EP was treated with both 0.01 micromol/L estradiol and 1 micromol/L progesterone, and group C was treated with 0.01% DMSO for control. Immunocytochemistry was used to examine the expression of cyclin G1 protein. MTT assay was used to evaluate metabolic activity of cells. Flow cytometry was used to check the number of cells distributing in each phase of the cell cycle. The result of immunocytochemistry showed that there was no expression of cyclin G1 protein in group C and group E, while cyclin G1 was obviously expressed in group P and group EP and localized in nucleus. In the MTT assay, compared with group C, the viability of group E significantly increased, while that of both group P and group EP decreased significantly. The results of flow cytometry were in accordance with those of MTT, which showed that compared with group C, group E had a higher proportion of cells in S phase, while group P, as well as group EP had a lower proportion of cells in S phase but a higher proportion in G1 phase and G2/M phase. These results indicate that progesterone could induce cyclin G1 expression in the primary culture of mouse endometrial epithelial cells, meanwhile inhibit the proliferation of cells and block the cell cycle progression. Thus, progesterone-induced expression of cyclin G1 is probably a negative factor in regulating cell cycle, which is involved in the inhibitory effect of progesterone on the proliferation of endometrial epithelial cells.


Assuntos
Proliferação de Células/efeitos dos fármacos , Ciclina G1/metabolismo , Células Epiteliais/metabolismo , Progesterona/farmacologia , Útero/citologia , Animais , Ciclo Celular , Divisão Celular , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Estradiol/farmacologia , Feminino , Citometria de Fluxo , Camundongos , Ovariectomia
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