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1.
Lancet Microbe ; 3(3): e193-e202, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35098177

RESUMO

BACKGROUND: Safe and effective vaccines are urgently needed to end the COVID-19 pandemic caused by SARS-CoV-2 infection. We aimed to assess the preliminary safety, tolerability, and immunogenicity of an mRNA vaccine ARCoV, which encodes the SARS-CoV-2 spike protein receptor-binding domain (RBD). METHODS: This single centre, double-blind, randomised, placebo-controlled, dose-escalation, phase 1 trial of ARCoV was conducted at Shulan (Hangzhou) hospital in Hangzhou, Zhejiang province, China. Healthy adults aged 18-59 years negative for SARS-CoV-2 infection were enrolled and randomly assigned using block randomisation to receive an intramuscular injection of vaccine or placebo. Vaccine doses were 5 µg, 10 µg, 15 µg, 20 µg, and 25 µg. The first six participants in each block were sentinels and along with the remaining 18 participants, were randomly assigned to groups (5:1). In block 1 sentinels were given the lowest vaccine dose and after a 4-day observation with confirmed safety analyses, the remaining 18 participants in the same dose group proceeded and sentinels in block 2 were given their first administration on a two-dose schedule, 28 days apart. All participants, investigators, and staff doing laboratory analyses were masked to treatment allocation. Humoral responses were assessed by measuring anti-SARS-CoV-2 RBD IgG using a standardised ELISA and neutralising antibodies using pseudovirus-based and live SARS-CoV-2 neutralisation assays. SARS-CoV-2 RBD-specific T-cell responses, including IFN-γ and IL-2 production, were assessed using an enzyme-linked immunospot (ELISpot) assay. The primary outcome for safety was incidence of adverse events or adverse reactions within 60 min, and at days 7, 14, and 28 after each vaccine dose. The secondary safety outcome was abnormal changes detected by laboratory tests at days 1, 4, 7, and 28 after each vaccine dose. For immunogenicity, the secondary outcome was humoral immune responses: titres of neutralising antibodies to live SARS-CoV-2, neutralising antibodies to pseudovirus, and RBD-specific IgG at baseline and 28 days after first vaccination and at days 7, 15, and 28 after second vaccination. The exploratory outcome was SARS-CoV-2-specific T-cell responses at 7 days after the first vaccination and at days 7 and 15 after the second vaccination. This trial is registered with www.chictr.org.cn (ChiCTR2000039212). FINDINGS: Between Oct 30 and Dec 2, 2020, 230 individuals were screened and 120 eligible participants were randomly assigned to receive five-dose levels of ARCoV or a placebo (20 per group). All participants received the first vaccination and 118 received the second dose. No serious adverse events were reported within 56 days after vaccination and the majority of adverse events were mild or moderate. Fever was the most common systemic adverse reaction (one [5%] of 20 in the 5 µg group, 13 [65%] of 20 in the 10 µg group, 17 [85%] of 20 in the 15 µg group, 19 [95%] of 20 in the 20 µg group, 16 [100%] of 16 in the 25 µg group; p<0·0001). The incidence of grade 3 systemic adverse events were none (0%) of 20 in the 5 µg group, three (15%) of 20 in the 10 µg group, six (30%) of 20 in the 15 µg group, seven (35%) of 20 in the 20 µg group, five (31%) of 16 in the 25 µg group, and none (0%) of 20 in the placebo group (p=0·0013). As expected, the majority of fever resolved in the first 2 days after vaccination for all groups. The incidence of solicited systemic adverse events was similar after administration of ARCoV as a first or second vaccination. Humoral immune responses including anti-RBD IgG and neutralising antibodies increased significantly 7 days after the second dose and peaked between 14 and 28 days thereafter. Specific T-cell response peaked between 7 and 14 days after full vaccination. 15 µg induced the highest titre of neutralising antibodies, which was about twofold more than the antibody titre of convalescent patients with COVID-19. INTERPRETATION: ARCoV was safe and well tolerated at all five doses. The acceptable safety profile, together with the induction of strong humoral and cellular immune responses, support further clinical testing of ARCoV at a large scale. FUNDING: National Key Research and Development Project of China, Academy of Medical Sciences China, National Natural Science Foundation China, and Chinese Academy of Medical Sciences.


Assuntos
COVID-19 , SARS-CoV-2 , Adulto , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , China , Humanos , Imunogenicidade da Vacina , Imunoglobulina G , Pandemias/prevenção & controle , Glicoproteína da Espícula de Coronavírus , Vacinas Sintéticas , Vacinas de mRNA
2.
Anim Biosci ; 34(3): 457-462, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32898960

RESUMO

OBJECTIVE: The aim of this study was to investigate the effects of Enteromorpha powder supplementation on reproduction-related hormones and genes in the late laying period of Zi geese. METHODS: A total of 312 (1-year-old) Zi geese with similar laying rate were randomly divided into 2 groups with 6 replicates each, each with 21 female geese and 5 male geese. The control group was fed with a basal diet and the test group was fed with a diet containing 3% Enteromorpha powder. The trial period lasted for 7 weeks. RESULTS: Our results showed that the laying rate was improved in the test group at each week of trial (p<0.01), and the levels of estradiol in serum and prolactin in ovary were increased compared with the control group (p<0.05). CONCLUSION: Based on above results, Enteromorpha powder supplementation at 3% could promote reproductive performance during the late laying period of Zi geese.

3.
Front Neurol ; 11: 602, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32719648

RESUMO

Objectives: To analyze the clinical characteristics of patients with benign paroxysmal positional vertigo (BPPV) diagnosed based on the diagnostic criteria of Bárány Society, verify the clinical application value of the diagnostic criteria, and further explore the clinical problems associated with the diagnosis of possible BPPV. Methods: A total of 481 patients with BPPV who were admitted from March 2016 to February 2019 were included. All patients were diagnosed by the Dix-Hallpike, straight head hanging and supine roll tests, the nystagmus was recorded using videonystagmography. For patients with possible BPPV (uncertain diagnosis), particle repositioning therapy and follow-up diagnosis were used to further clarify diagnosis. Results: Based on Bárány Society's diagnostic criteria for BPPV, the distribution characteristics of different BPPV types were as follows: 159 (33.1%) patients had posterior canal BPPV-canalolithiasis (PC-BPPV-ca), 70 (14.6%) patients had horizontal canal BPPV-ca (HC-BPPV-ca), 55 (11.4%) patients had spontaneously resolved-probable-BPPV (Pro-BPPV), and 53 (11.0%) patients had HC-BPPV-cupulolithiasis (HC-BPPV-cu). In emerging and controversial BPPV, 51 (10.6%) patients had multiple canal BPPV (MC-BPPV), 30 (6.2%) patients had PC-BPPV-cu, and 19 (4.0%) patients had anterior canal BPPV-ca (AC-BPPV-ca), 44 (9.1%) patients had possible-BPPV (Pos-BPPV). Among the 44 patients with Pos-BPPV, 23 patients showed dizziness/vertigo without nystagmus during the initial positional test, five patients were possible MC-BPPV, four patients had persistent geotropic positional nystagmus lasting > 1 min when lying on both sides, and were considered to have Pos-HC-BPPV, four patients showed apogeotropic nystagmus when lying on one side, and were considered to have possible short-arm HC-BPPV, four patients showed geotropic nystagmus when lying on one side, and were considered to have Pos-HC-BPPV, three patients had down-beating nystagmus, lasing > 1 min, were considered to have Pos-AC-BPPV-cu. One patient showed transient apogeotropic positional nystagmus on both sides during the supine roll test, and was diagnosed with possible anterior arm HC-BPPV. Conclusions: PC-BPPV-ca is the most common among patients with BPPV, followed by HC-BPPV-ca. In emerging and controversial BPPV, MC-BPPV, and Pos-BPPV were more common. For the diagnosis of Pos-BPPV, a combination of the history of typical BPPV, particle repositioning therapy and follow-up outcome is helpful to clarify the diagnosis.

4.
Chin Med J (Engl) ; 132(3): 269-274, 2019 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-30681492

RESUMO

BACKGROUND: Studies on the relationship between antiepileptic drug (AED) administration and clinical outcomes in patients with mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) remain scarce. Levetiracetam (LEV) is an AED that is neuroprotective in various neurologic disorders. This study aimed to determine the impact of LEV on the outcome of MELAS. METHODS: A retrospective, single-center study was performed based on a large cohort of patients with MELAS with a history of seizures (n = 102). Decisions on antiepileptic therapies were made empirically. Patients were followed up for 1 to 8 years (median, 4 years) and divided into 2 groups based on whether LEV was administered (LEV or non-LEV). The modified Rankin scale (mRS) scores and mortality risks were analyzed in all patients. RESULTS: LEV, carbamazepine, benzodiazepines, topiramate, oxcarbazepine, valproate, and lamotrigine were administered in 48, 37, 18, 13, 11, 9, and 9 patients, singly or in combination, respectively. The mean mRS score of the LEV group (n = 48) was lower than that of the non-LEV group (n = 54; mean ±â€Šstandard deviation, 2.79 ±â€Š1.47 vs. 3.83 ±â€Š1.93, P = 0.006) up to the end of the study. Nevertheless, there was no difference in the proportion of subjects without disability (mRS ranging 0-1) between the groups (P = 0.37). The multivariate regressions revealed that LEV treatment was associated with lower mRS scores (odds ratio 0.32, 95% confidence interval [CI] 0.15-0.68, P = 0.003) and mortality rates (hazard ratio 0.24, 95% CI 0.08-0.74, P = 0.013). There was a significant difference in the Kaplan-Meier survival curves between the groups (χ = 4.29, P = 0.04). CONCLUSIONS: The LEV administration is associated with lower mortality in patients with MELAS in this retrospective study. Further laboratory research and prospective cohort studies are needed to confirm whether LEV has neuroprotective effects on patients with mitochondrial diseases.


Assuntos
Acidose Láctica/tratamento farmacológico , Acidose Láctica/mortalidade , Anticonvulsivantes/uso terapêutico , Levetiracetam/uso terapêutico , Encefalomiopatias Mitocondriais/tratamento farmacológico , Encefalomiopatias Mitocondriais/mortalidade , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/mortalidade , Adolescente , Carbamazepina/uso terapêutico , Criança , Pré-Escolar , Feminino , Humanos , Lamotrigina/uso terapêutico , Levetiracetam/administração & dosagem , Masculino , Oxcarbazepina/uso terapêutico , Estudos Prospectivos , Estudos Retrospectivos , Topiramato/uso terapêutico , Ácido Valproico/uso terapêutico
5.
Int J Neurosci ; 129(2): 103-109, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29883219

RESUMO

PURPOSE: To report the clinical features and gene mutations in four episodic ataxia type 2 (EA2) patients whose main presentation was recurrent dizziness/vertigo. METHODS: Clinical data of four EA2 patients (three familial EA2 cases and one sporadic case) with recurrent dizziness/vertigo were collected to assess nystagmus and eye movement. Gene mutations were identified by whole exome sequencing. RESULTS: The three patients in family 1 experienced disease onset before 8 years of age, presented with a chief complaint of episodic dizziness, muscle weakness of the lower limbs and the inability to walk. These symptoms lasted a few hours and then subsided. The proband also had gaze-evoked nystagmus during attacks. Videonystagmography demonstrated that the saccade velocity was low, smooth pursuit was type III, and gain was abnormal at 0.1, 0.2 and 0.4 Hz. An optokinetic nystagmus test showed that the left eye optokinetic nystagmus disappeared, and the right eye optokinetic nystagmus weakened. A head-shaking test produced a left horizontal nystagmus. Gene analysis identified a novel c.1558 + 2T > G splice site mutation in the CACNA1A gene in the proband and his mother. The fourth patient was sporadic, with an onset age of 3 years. He mainly suffered from episodic vertigo, accompanied by severe anxiety and depression. He carried a CACNA1A mutation, c.4636C > T, which is a previously reported pathogenic mutation. CONCLUSIONS: The onset of symptoms in these EA2 patients was early. The patients mainly presented recurrent dizziness/vertigo, with the absence of characteristic episodic ataxia. Detection of CACNA1A mutations facilitates the diagnosis of EA2.


Assuntos
Ataxia/diagnóstico , Ataxia/genética , Tontura/diagnóstico , Nistagmo Patológico/diagnóstico , Nistagmo Patológico/genética , Vertigem/diagnóstico , Adolescente , Adulto , Ataxia/complicações , Canais de Cálcio/genética , Tontura/complicações , Movimentos Oculares , Feminino , Humanos , Masculino , Mutação , Nistagmo Patológico/complicações , Vertigem/complicações , Adulto Jovem
6.
World J Pediatr ; 10(2): 126-32, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24801232

RESUMO

BACKGROUND: We determined the clinical and molecular genetic characteristics of 8 Chinese patients with Ullrich congenital muscular dystrophy (UCMD). METHODS: Clinical data of probands were collected and muscle biopsies of patients were analyzed. Exons of COL6A1, COL6A2 and COL6A3 were analyzed by direct sequencing. Mutations in COL6A1, COL6A2 and COL6A3 were identified in 8 patients. RESULTS: Among these mutations, 5 were novel [three in the triple helical domain (THD) and 2 in the second C-terminal (C2) domain]. We also identified five known missense or in-frame deletion mutations in THD and C domains. Immunohistochemical studies on muscle biopsies from patients showed reduced level of collagen VI at the muscle basement membrane and mis-localization of the protein in interstitial and perivascular regions. CONCLUSIONS: The novel mutations we identified underscore the importance of THD and C2 domains in the assembly and function of collagen VI, thereby providing useful information for the genetic counseling of UCMD patients.


Assuntos
Colágeno Tipo VI/genética , Distrofias Musculares/genética , Mutação , Esclerose/genética , Adolescente , Alelos , Substituição de Aminoácidos , Biópsia , Criança , Pré-Escolar , China , Códon , Feminino , Mutação da Fase de Leitura , Humanos , Imuno-Histoquímica , Masculino , Distrofias Musculares/diagnóstico , Mutação de Sentido Incorreto , Polimorfismo de Nucleotídeo Único , Esclerose/diagnóstico , Deleção de Sequência
7.
Zhonghua Yi Xue Za Zhi ; 92(40): 2830-4, 2012 Oct 30.
Artigo em Chinês | MEDLINE | ID: mdl-23290211

RESUMO

OBJECTIVE: To summarize the clinical audiologic features of patients with mitochondrial DNA (mtDNA) A3243G mutation and explore the lesion location of hearing loss so as to examine its correlation with the related syndrome. METHODS: A total of 44 patients with mtDNA A3243G mutation from 2009-2011 were studied. Audiological evaluations consisted of measurements of pure-tone and speech audiometry, tympanometry, distortion-product otoacoustic emissions and auditory brainstem response. We investigated a possible correlation between the degree of hearing loss and gender, age and mutation rate. RESULTS: (1) Pure tone test was performed in 41 patients and showed normal hearing or symmetrical sensorineural hearing loss. Pure tone audiogram (PTA) showed high-frequency loss and descending curve in a majority of patients. There were 75 ears with hearing loss in 82 ears (91.46%), 22 ears with abnormal speech audiometry in 26 ears, 77 ears with abnormal distortion product otoacoustic emissions (DPOAE)testing in 86 ears, including 5 ears with normal PTA, 31 ears with abnormal electrocochleography in 75 ears, 25 ears with abnormal auditory brainstem response (ABR) in 82 ears. The abnormal ABR showed elevated threshold in 10 ears, delayed interpeak latencies of wave I-V in 2 ears and disappearance of wave V before wave I in 1 ear. In addition, there were 2 ears with speech audiometry abnormal but with normal ABR. (2) The correlation between the severity of hearing and gender did not reach statistical significance, nor the severity of hearing and mutation ratio. Age could influence the hearing of A3243G-induced MELAS. CONCLUSIONS: The predominant lesions of mtDNA A3243G is at cochlea and retrocochlear sites. Significant variations in clinical manifestation of hearing are the prominent features in patient with A3243G mutation. There was no correlation between the degree of hearing loss and mutation load. However, hearing impairment is the most common symptom of A3243G mutation.


Assuntos
DNA Mitocondrial/genética , Perda Auditiva Neurossensorial/genética , Taxa de Mutação , Adolescente , Adulto , Criança , Feminino , Perda Auditiva Neurossensorial/diagnóstico , Testes Auditivos , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
8.
Zhonghua Yi Xue Za Zhi ; 92(40): 2835-8, 2012 Oct 30.
Artigo em Chinês | MEDLINE | ID: mdl-23290212

RESUMO

OBJECTIVE: To report the clinical features of mitochondrial disease caused by mitochondrial DNA (mtDNA) A8344G point mutation. METHODS: We analyzed the clinical presentations and muscular pathological changes in 10 patients with genetically confirmed mtDNA A8344G point mutation. RESULTS: Among them, 6 patients presented as juvenile-onset myoclonic epilepsy with ragged red fibers (MERRF) syndrome, 2 suffered infant-onset Leigh syndrome and the remaining 2 were diagnosed as limb-girdle mitochondrial myopathy. The mtDNA A8344G mutation load from muscle samples showed that patients with Leigh syndrome>MERRF syndrome>mitochondrial myopathy (87.2%, 88.4%>69.0%-86.8%>67.2%, 58.4%). CONCLUSIONS: Mitochondrial disease caused by A8344G point mutation shows a great heterogeneity. The mutation load of muscle mtDNA might be associated with the severity of clinical phenotype, the higher mutation load, the more severe clinical presentations.


Assuntos
DNA Mitocondrial/genética , Mutação Puntual , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Doença de Leigh/genética , Síndrome MERRF/genética , Masculino , Pessoa de Meia-Idade , Miopatias Mitocondriais/genética , Distrofia Muscular do Cíngulo dos Membros/genética , Adulto Jovem
9.
Nan Fang Yi Ke Da Xue Xue Bao ; 30(6): 1222-5, 2010 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-20584642

RESUMO

OBJECTIVE: To develop a real-time PCR-based chromatin immunoprecipitation (ChIP) assay for determining the effect of sodium butyrate on acetylation of histone in gamma-globin gene promoter regions in K562 cells. METHODS: K562 cells were grown in the presence or absence of 0.5 mmol/L sodium butyrate for 48 h, and 1=10(7) cells per group were used for real-time PCR-based ChIP with anti-acetylated histone H3 or H4 antibodies. The levels of acetylated histone H3 and H4 (acH3 and acH4) in Ggamma- and Agamma-globin gene promoter regions were measured. RESULTS: In the K562 cells with sodium butyrate treatment or without any treatment, the levels of acH3 or acH4 in Ggamma- or Agamma-globin gene promoter were higher than that in the necdin gene (negative control). Compared with the untreated K562 cells, the cells treated with 0.5 mmol/L sodium butyrate showed a 3.1-fold or 2.6-fold increase in acH3 or acH4 in Ggamma-globin gene promoter region, with also a 3.7-fold or 3.2-fold increase in acH3 or acH4 in Agamma-globin gene promoter region, respectively (P<0.01). CONCLUSION: We have successfully developed a real-time PCR-based ChIP assay for analyzing the acetylation of histone H3 and H4 in gamma-globin gene promoter regions. Our results support the role of sodium butyrate in increasing the level of acetylated histone in gamma-globin gene promoter regions.


Assuntos
Butiratos/farmacologia , Histonas/química , Regiões Promotoras Genéticas/genética , gama-Globinas/genética , Acetilação , Imunoprecipitação da Cromatina/métodos , Humanos , Células K562 , Reação em Cadeia da Polimerase em Tempo Real/métodos
10.
J Ethnopharmacol ; 127(2): 242-50, 2010 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-19922785

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Astragalus polysaccharide (APS), obtained from Astragalus membranaceus, displays a range of activities in many systems, including the promotion of immune responses, anti-inflammation, and the protection of vessels. It possesses potent pharmacological activity on differentiation to the erythroid lineage. AIM OF THE STUDY: To investigate the effects of APS on the erythroid differentiation and the mechanism of action by microarray analysis in K562 cells. MATERIALS AND METHODS: Benzidine staining, semi-quantitative RT-PCR, Western blot and microarray methods were used to survey the effects of APS on inducing erythroid differentiation and the changes of gene expression profile in K562 cells. RESULTS: Of the 13.2% positive cells detected by benzidine staining, the induction was the highest with 200 microg/ml APS on 72h. Ggamma-mRNA expression and fetal hemoglobin synthesis were significantly up-regulated. Microarray analysis showed that 31 genes were up-regulated and 108 genes were down-regulated. These differential expression genes generally regulate protein binding, cellular metabolic process, the cell proliferation, and transcriptional activator activity. The gamma-globin gene was up-regulated, the genes related with erythroid differentiation such as LMO2, Runx1 and GTF2I were up-regulated, while Bklf, Eklf, EPHB4 and Sp1 were down-regulated. CONCLUSIONS: Our studies indicate that APS indicate potent activities on the erythroid differentiation by modulating genes of LMO2, Klf1, Klf3, Runx1, EphB4 and Sp1, increasing gamma-globin mRNA expression and fetal hemoglobin synthesis in K562 cells.


Assuntos
Astragalus propinquus , Linhagem da Célula/efeitos dos fármacos , Células Eritroides/efeitos dos fármacos , Polissacarídeos/farmacologia , Análise Serial de Proteínas/métodos , Linhagem da Célula/fisiologia , Proliferação de Células/efeitos dos fármacos , Células Eritroides/citologia , Células Eritroides/metabolismo , Humanos , Células K562 , Polissacarídeos/isolamento & purificação
11.
J Hazard Mater ; 175(1-3): 179-86, 2010 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-19850409

RESUMO

A new hybrid material was developed by the template-free hybridization of weak acidic pink red B (APRB, C.I. 18073) with BaSO(4). The composition and structure of the material were determined and characterized. In contrast to conventional sorbents, the hybrid material has a specific surface area of 0.89 m(2)/g, but it contains lots of negative charges and lipophilic groups as the basis of specific adsorption. The efficient removal of cationic dyes and persistent organic pollutants (POPs) indicates that it has an improved adsorption capacity and selectivity with a short removal time less than 2 min; while the hybrid sorbents fit the Langmuir isotherm model, and follow the octanol-water partition law. Instead of using APRB reagent, an APRB-producing wastewater was reused to prepare the cost-effective sorbent, and the equilibrium adsorption capacities of which reached 222 and 160 mg/g for EV and BPR, respectively. The sorbents was then used to treat three wastewater samples with satisfactory results of over 97% decolonization and 88% COD-decreasing. In addition, the hybrid sorbent was regenerated from sludge over five cycles, and its adsorption capacity was not appreciably changed. This work has developed a simple and eco-friendly method for synthesizing a practical and efficient sorbent.


Assuntos
Sulfato de Bário/química , Corantes/química , Purificação da Água/métodos , Ácidos/química , Adsorção , Cátions , Corantes/isolamento & purificação , Concentração de Íons de Hidrogênio , Resíduos Industriais , Cinética , Microscopia Eletrônica de Varredura/métodos , Compostos Orgânicos , Fatores de Tempo , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análise
12.
Environ Sci Pollut Res Int ; 17(1): 97-105, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19263103

RESUMO

BACKGROUND, AIM, AND SCOPE: Over the years, organic pollution in the environment has aroused people's concern worldwide, especially persistent organic pollutants (POPs). Particularly in developing countries, plenty of concentrated organic wastewaters treated noneffectively are discharged into aquatic environments from chemical, textile, paper-making, and other industries to seriously threaten the surface and drinking water. The conventional wastewater treatment techniques are often helpless due to high cost with multilevel processing. Adsorption as an efficient method is often applied to the treatment of wastewater. The aim of this work is to develop an eco-friendly and cost-effective wastewater-sorbing material with weak acidic pink red B (APRB) and calcium carbonate (CaCO(3)) by reusing highly concentrated dye wastewater. MATERIALS AND METHODS: On the basis of the chemical coprecipitation of APRB with growing CaCO(3) particles, an inclusion material was prepared. The composition of material was determined by atomic absorption spectrometry, thermogravimetric analysis, and transmission electron microscopy (TEM)-energy dispersive X-ray, and its morphology characterized by X-ray diffraction, scanning electron microscopy, TEM, and particle-size analysis. Two cationic dyes, ethyl violet (EV) and methylene blue (MB), and four POPs, phenanthrene (Phe), fluorene (Flu), biphenyl (Bip), and biphenol A (Bpa), were used to investigate the adsorption selectivity, capacity, and mechanism of the new material, where spectrophotometry, fluorophotometry, and high-performance liquid chromatography were used for determination. An APRB-producing wastewater was reused for preparing the cost-effective wastewater-sorbing material instead of the APRB reagent and then treating cationic dye wastewaters. The remove rates of colority and chemical oxygen demand (COD) were evaluated. RESULTS AND DISCUSSION: The CO(3) (2-)-APRB-Ca(2+) addition sequence is most favorable for the occlusion of APRB into the growing CaCO(3) particles, and the occlusion of APRB corresponded to the Langmuir isothermal adsorption with the binding constant (K) of 5.24 x 10(4) M(-1) and the Gibbs free energy change (Delta G) of -26.9 kJ/mol. The molar ratio of Ca(2+) to CO(3) (2-) and APRB was calculated to be 1:0.94:0.0102, i.e., approximately 92 CaCO(3) molecules occluded only one APRB. Approximately 78% of the inclusion aggregates are between 3 and 20 mm and the particles are global-like with 50-100 nm. The element mapping on Ca, S, and C indicated APRB distributed a lot of CaCO(3), i.e., the APRB layer may be pressed between both sides of CaCO(3) layers. The molar ratio of Ca to S was calculated to 44, i.e., 88 CaCO(3) molecules carried one APRB, according to the above data. During the growing of CaCO(3) particles, APRB may be attracted into the temporary electric double layer in micelle form by the strong charge interaction between sulfonic groups of APRB and Ca(2+) and the hydrophobic stack of long alkyl chains. Four dyes were adsorbed: reactive brilliant red X-3B and weak acid green GS as anionic dyes and EV and MB as cationic dyes. The removals of EV and MB are extremely obvious and the saturation adsorption of EV and MB just neutralized all the negative charges in the inclusion particles. The selectivity demonstrated the ion-pair attraction, i.e., the cationic adsorption capacity depends on the negative charge number of the inclusion material. By fitting the Langmuir isotherm model, the monolayer adsorptions of EV and MB were confirmed. Their K values were calculated to be 2.4 x 10(6) and 7.3 x 10(5) M(-1), and Delta G was calculated to be 36.4 and -33.4 kJ/mol. The adsorption of four POPs on the material obeyed the lipid-water partition law, and their partition coefficients (K (pw)) were calculated to be 9,342 L/kg for Phe, 7,301 L/kg for Flu, 1,226 L/kg for Bip, and 870 L/kg for Bpa. The K (pw) is the direct ratio to their lipid-water partition coefficients (K (ow)) with 0.314 of slope. Besides this, a cost-effective CaCO(3)/APRB inclusion material was prepared with an APRB-producing wastewater instead of APRB reagent, and it was used in the treatment of two practical cationic dye wastewaters (samples A and B). The colority and COD in sample B are 18 and 13 times high as those of sample A. The decolorization of sample A is over 96%, and the removal of COD is between 70% and 80% when more than 0.3% adsorbent was added. However, those of sample B are over 98% and 88% in the presence of over 1% adsorbent. The adsorbent added in sample B, which was only two to three times as high as that in sample A, brought a similar removal rate of colority and COD. The inclusion material is more efficient for treatment of a highly concentrated dye wastewater because it may adsorb the most cationic dye up to saturation. CONCLUSIONS: A cost-effective onion-like inclusion material was synthesized with the composition ratio 90 +/- 2 of CaCO(3) to APRB, and it carried a lot of negative charges and lipophilic groups. It has a high adsorption capacity and rapid saturation for cationic dye and POPs. The adsorption of cationic dyes corresponded to the Langmuir isothermal model and that of POPs to the lipid-water partition law. The adsorbent is suitable for treatment of concentrated cationic dye and POPs wastewater in neutral media. The addition quantity of the calcium carbonate-APRB adsorbent was suggested below: only 3-5 kg per ton of wastewater (<1,000 colority or <2 mg/L POPs) and 20-30 kg per ton of highly concentrated wastewater (>20,000 colority or >50 mg/L POPs). RECOMMENDATIONS AND PERSPECTIVES: The skeleton reactants are low-cost, easily available, and harmless to the ecological environment; additionally, the APRB reactant can reuse APRB-producing wastewater. The dye-contaminated sludge can potentially be reused as the color additive in building material and rubber and plastics industries. However, the APRB and dye contaminant would be released from the sludge when exposed to an acidic media (pH <4) for long time. This work has developed a simple, eco-friendly and practical method for the production of a cost-effective wastewater-sorbing material.


Assuntos
Compostos Azo/química , Carbonato de Cálcio/química , Resíduos Industriais , Naftalenossulfonatos/química , Indústria Têxtil , Eliminação de Resíduos Líquidos/economia , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Resíduos Industriais/economia , Resíduos Industriais/prevenção & controle
13.
Nan Fang Yi Ke Da Xue Xue Bao ; 29(5): 939-42, 2009 May.
Artigo em Chinês | MEDLINE | ID: mdl-19460714

RESUMO

OBJECTIVE: To investigate the effects of Astragalus polysaccharides (APS) in inducing the mRNA expression of Agamma- and Ggamma-globin in K562 cells. METHODS: K562 cells were treated with APS at the concentration of 150, 300, and 450 mg/L, with Na-butyrate (NaB)-treated cells serving as the positive control and untreated cells as the blank control. Benzidine staining was used to examine the changes in hemoglobin synthesis in K562 cells after the treatments, and RT-PCR was employed to investigate the mRAN expression of Agamma- and Ggamma-globin. RESULTS: Compared with the untreated cells, APS treatment (300 mg/L) for 48 h resulted in a significant increase of the percentages of benzidine-positive cells from (4.37-/+0.58)% to (15.67-/+1.80)%, and also in significantly increased expression of Agamma-globin and Ggamma-globin mRNAs by 3.59-/+0.16 and 5.02-/+0.81 folds, respectively (P=0.000). CONCLUSION: APS potently enhances the mRNA expression of Agamma- and Ggamma-globin in K562 cells and warrants further evaluation as a potential therapeutic agent for beta-thalassemia.


Assuntos
Astragalus propinquus/química , Polissacarídeos/farmacologia , gama-Globinas/metabolismo , Humanos , Células K562 , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , gama-Globinas/genética
14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 26(7): 1318-21, 2006 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-17020049

RESUMO

Nanometer-sized L-cysteine-capped ZnS particles as a fluorescence probe were synthesized, and the effect of proteins on the fluorescence intensity has been investigated. With deltalambda = 190 nm, the maximum and constant synchronous fluorescence enhancement was produced at 268.0 nm and pH 5.12 in the presence of proteins. A highly sensitive synchronous fluorescence method for the rapid determination of proteins was developed. Under optimum conditions, the calibration curve was linear over the range 0.05-6.0 microg x mL(-1) for human serum albumin (HSA), and 0.05-8.0 microg x mL(-1) for gamma-globulin (gamma-G), respectively. The relative standard deviations of seven measurements were 1.90% for 1.0 microg x mL(-1) HSA, and 1.65% for 1.0 microg mL(-1) gamma-G.


Assuntos
Proteínas Sanguíneas/análise , Cisteína/análise , Corantes Fluorescentes/análise , Humanos , Nanopartículas/química , Sulfetos/análise , Compostos de Zinco/análise
15.
Anal Bioanal Chem ; 378(3): 811-5, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14647943

RESUMO

Nanometer-sized L-cysteine-capped ZnS particles have been synthesized and used as a fluorescence probe to investigate the effect of proteins on fluorescent intensity. With Delta lambda=190 nm, maximum and constant synchronous fluorescence enhancement was produced at 267 nm and pH 5.12 in the presence of proteins. A highly sensitive synchronous fluorescence method for the rapid determination of proteins has been developed. Under optimum conditions, calibration graphs are linear over the range 0.03-8.0 microg mL(-1) for bovine serum albumin (BSA), 0.01-6.0 microg mL(-1) for human serum albumin (HSA), 0.05-8.0 microg mL(-1) for gamma-globulin (gamma-G), and 0.04-4.0 microg mL(-1) for ovalbumin, respectively. The relative standard deviations of seven replicate measurements were 1.75% for 1.0 microg mL(-1) BSA, 1.90% for 1.0 microg mL(-1) HSA, 1.65% for 1.0 microg mL(-1) gamma-G, and 2.32% for 1.0 microg mL(-1) ovalbumin.


Assuntos
Cisteína/química , Corantes Fluorescentes/química , Proteínas/análise , Sulfetos/química , Compostos de Zinco/química , Calibragem , Microscopia Eletrônica , Nanotecnologia
16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 23(1): 203-4, 2003 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-12940010

RESUMO

A new catalytic fluorimetric method for the determination of trace oxalate has been developed. The method is based on the catalytic effect of oxalate on the oxidation of potassium dichromate with rhodamine B in sulfuric acid medium. The catalytic reaction takes place at 50 degrees C for 10 min in a water bath and is a pseudo-zero-order reaction. The regression equation of calibration graph is delta F = 8.42c (mg.L-1) + 3.81 (r = 0.9983), and measuring range is 0.4-12.0 mg.L-1, and the detection limit is 0.16 mg.L-1. Interferences of 30 diverse materials were examined. The method has been applied to the determination of oxalate in biological samples with satisfactory results.


Assuntos
Medições Luminescentes , Oxalatos/análise , Spinacia oleracea/química , Catálise , Fluorometria/métodos , Oxirredução , Dicromato de Potássio/química , Rodaminas/química
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