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1.
Stat Methods Med Res ; 33(1): 112-129, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38155544

RESUMO

Modern medical devices are increasingly producing complex data that could offer deeper insights into physiological mechanisms of underlying diseases. One type of complex data that arises frequently in medical imaging studies is functional data, whose sampling unit is a smooth continuous function. In this work, with the goal of establishing the scientific validity of experiments involving modern medical imaging devices, we focus on the problem of evaluating reliability and reproducibility of multiple functional data that are measured on the same subjects by different methods (i.e. different technologies or raters). Specifically, we develop a series of intraclass correlation coefficient and concordance correlation coefficient indices that can assess intra-method, inter-method, and total (intra + inter) agreement based on multivariate multilevel functional data consisting of replicated functional data measurements produced by each of the different methods. For efficient estimation, the proposed indices are expressed using variance components of a multivariate multilevel functional mixed effect model, which can be smoothly estimated by functional principal component analysis. Extensive simulation studies are performed to assess the finite-sample properties of the estimators. The proposed method is applied to evaluate the reliability and reproducibility of renogram curves produced by a high-tech radionuclide image scan used to non-invasively detect kidney obstruction.


Assuntos
Reprodutibilidade dos Testes , Humanos , Variações Dependentes do Observador , Simulação por Computador
2.
Front Neurosci ; 17: 1267639, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38027484

RESUMO

Introduction: The field of machine learning has undergone a significant transformation with the progress of deep artificial neural networks (ANNs) and the growing accessibility of annotated data. ANNs usually require substantial power and memory usage to achieve optimal performance. Spiking neural networks (SNNs) have recently emerged as a low-power alternative to ANNs due to their sparsity nature. Despite their energy efficiency, SNNs are generally more difficult to be trained than ANNs. Methods: In this study, we propose a novel three-stage SNN training scheme designed specifically for segmenting human hippocampi from magnetic resonance images. Our training pipeline starts with optimizing an ANN to its maximum capacity, then employs a quick ANN-SNN conversion to initialize the corresponding spiking network. This is followed by spike-based backpropagation to fine-tune the converted SNN. In order to understand the reason behind performance decline in the converted SNNs, we conduct a set of experiments to investigate the output scaling issue. Furthermore, we explore the impact of binary and ternary representations in SNN networks and conduct an empirical evaluation of their performance through image classification and segmentation tasks. Results and discussion: By employing our hybrid training scheme, we observe significant advantages over both ANN-SNN conversion and direct SNN training solutions in terms of segmentation accuracy and training efficiency. Experimental results demonstrate the effectiveness of our model in achieving our design goals.

3.
Res Sq ; 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37886529

RESUMO

Background: The most widely used technologies for profiling microbial communities are 16S marker-gene sequencing and shotgun metagenomic sequencing. Interestingly, many microbiome studies have performed both sequencing experiments on the same cohort of samples. The two sequencing datasets often reveal consistent patterns of microbial signatures, highlighting the potential for an integrative analysis to improve power of testing these signatures. However, differential experimental biases, partially overlapping samples, and differential library sizes pose tremendous challenges when combining the two datasets. Currently, researchers either discard one dataset entirely or use different datasets for different objectives. Methods: In this article, we introduce the first method of this kind, named Com-2seq, that combines the two sequencing datasets for testing differential abundance at the genus and community levels while overcoming these difficulties. The new method is based on our LOCOM model (Hu et al., 2022), which employs logistic regression for testing taxon differential abundance while remaining robust to experimental bias. To benchmark the performance of Com-2seq, we introduce two ad hoc approaches: applying LOCOM to pooled taxa count data and combining LOCOM p-values from analyzing each dataset separately. Results: Our simulation studies indicate that Com-2seq substantially improves statistical efficiency over analysis of either dataset alone and works better than the two ad hoc approaches. An application of Com-2seq to two real microbiome studies uncovered scientifically plausible findings that would have been missed by analyzing individual datasets. Conclusions: Com-2seq performs integrative analysis of 16S and metagenomic sequencing data, which improves statistical efficiency and has the potential to accelerate the search of microbial communities and taxa that are involved in human health and diseases.

4.
bioRxiv ; 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37425938

RESUMO

The most widely used technologies for profiling microbial communities are 16S marker-gene sequencing and shotgun metagenomic sequencing. Interestingly, many microbiome studies have performed both sequencing experiments on the same cohort of samples. The two sequencing datasets often reveal consistent patterns of microbial signatures, highlighting the potential for an integrative analysis to improve power of testing these signatures. However, differential experimental biases, partially overlapping samples, and differential library sizes pose tremendous challenges when combining the two datasets. Currently, researchers either discard one dataset entirely or use different datasets for different objectives. In this article, we introduce the first method of this kind, named Com-2seq, that combines the two sequencing datasets for the objective of testing differential abundance at the genus and community levels while overcoming these difficulties. We demonstrate that Com-2seq substantially improves statistical efficiency over analysis of either dataset alone and works better than two ad hoc approaches.

5.
J Environ Sci (China) ; 126: 423-433, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36503769

RESUMO

Decomposition of the polycation Al13O4(OH)24(H2O)127+ (Al13) promoted by ligand is a vital subject to advance our understanding of natural and artificial occurrence and evolution of aluminum ions, especially in the case of acidic condition that dissolved Al3+ species can be released from the Al-bearing substances. However, the microscopic pathway of synchronous proton-promoted and ligand-promoted decomposition process for Al13 is still in the status of ambiguity. Herein, we applied differential mass spectrometry method and DFT calculation to study the initial detailed process of Al13 decomposition under the presence of proton and salicylic acid (H2Sal). Mass results showed that the mononuclear Al3+-H2Sal complexes dominated the resulting Al species, whereas the monodentate complex Al13HSal6+ was not observed in the spectra. The difference of decomposition levels between the ligand/Al ratio 0.2 and 0.5 cases revealed that proton and ligand performed synergistic effect in initial Al13 decomposition process, and the proton transfer determined the ring closure efficiency. The ring closure reaction is the prerequisite for the collapse of Al13 structure and detachment of the mononuclear complex. DFT calculations reveal that hydrogen bond plays an important role in inducing the formation of chelated complex accompanying proton transfer. Attachment of protons at the bridging OH- can elongate and weaken the critical bond between targeted Al3+ and µ4-O2- resulting from delocalization of electron pairs in the oxygen atom. These results demonstrate the detailed mechanism of Al13 composition promoted by ligand and proton, and provide significant understanding for further application and control of Al13.


Assuntos
Prótons , Ácido Salicílico , Ligantes , Espectrometria de Massas , Oxigênio
6.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-991902

RESUMO

Objective:To analyze and compare the association between different obesity-related indices and vitamin D deficiency in middle-aged and elderly population dwelled in Lanzhou city.Methods:From May, 2011 to September, 2012, middle-aged and elderly individuals with complete baseline data were included via randomly cluster sampling from 3 communities in Lanzhou. The subjects were divided into 4 subgroups by vitamin D levels and various obesity-related indices were compared across subgroups with the same gender. The relationship between the obesity-related indices and the severity of vitamin D deficiency was analyzed using Spearman correlation analysis, and the effects of different obesity-related indices on the severity of vitamin D deficiency was analyzed using multivariate logistic regression analysis.Results:A total of 9 437 residents were included. The overall prevalence of vitamin D deficiency was 97.7%. Compared with the group with lower vitamin D level, participants in the group with higher vitamin D level showed evidently lower body mass index (BMI), waist circumference (WC), lipid accumulation product (LAP), visceral adiposity index (VAI) and triglyceride/ high density lipoprotein cholesterol (TG/HDL-C) ratio in the total population and females, while only WC, LAP, VAI and TG/HDL-C in the males (all P<0.05). Spearman correlation analysis showed that BMI, WC, LAP, VAI and TG/HDL-C were positively correlated with the severity of vitamin D deficiency in the total population and the females, while only LAP, VAI and TG/HDL-C in the males (all P<0.05) . Multivariate logistic regression analysis showed that higher levels of these obesity related indices were correlated with more severe vitamin D deficiency in the total population and the females, while only higher LAP, VAI and TG/HDL-C in the males (all P<0.05). The effects of higher LAP was the most prominant in the total population ,the females and the males. Conclusion:Various obesity phenotypes are closely related to vitamin D deficiency in middle-aged and elderly women, while only visceral obesity and abnormal lipid metabolism are related to vitamin D deficiency in middle-aged and elderly men, with LAP being the most important influencing factor.

7.
Acta Pharmaceutica Sinica ; (12): 3040-3048, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-999066

RESUMO

In this study, the ovarian surgery (ovariectomy, OVX) was used to establish the osteoporosis mice model of primary menstruation, in order to evaluate the protective effects and mechanisms of Zhibai Dihuang decotion on postmenopausal osteoporosis (PMOP). The animal experimental protocol has been reviewed and approved by Laboratory Animal Ethics Committee of Jinan University (number: 20210315-03), in compliance with the Institutional Animal Care Guidelines. C57BL/6 mice were divided into five groups, including Sham group, OVX group, low (32 g·kg-1·day-1) and high dose (64 g·kg-1·day-1) of Zhibai Dihuang decotion groups, positive drug group (alendronate, 9.9 mg·kg-1·q3d). After modeling, mice were given medication intervention for 8 weeks, and then femoral and tibial tissues were taken to detect indicators such as bone microstructure, bone resorption, and oxidative stress. The experimental results showed that after Zhibai Dihuang decotion administration, the bone microstructure damage caused by OVX surgery was alleviated, and the relevant parameters bone mineral density (BMD), bone volume/total volume (BV/TV), trabecular number (Tb. N) and connectivity density (Conn. D) both significantly increased. At the same time, the number of TRAP positive osteoclasts decreased significantly, and the levels of proteins and genes related to osteoclast differentiation decreased, indicating that Zhibai Dihuang decoction could inhibit the increased activity of osteoclast caused by OVX. Afterwards, network pharmacology was used to construct the active compound action target network of Zhibai Dihuang decotion, and it was found that the target genes of its active ingredients were closely related to the oxidative stress pathway. Finally, the detection results of oxidative stress levels in bone tissues showed that after treatment with Zhibai Dihuang decotion, the levels of oxidative stress products 4-hydroxynonenal (4-HNE) and malondialdehyde (MDA) in bone tissues of mice significantly decreased, while the levels of antioxidant stress substance L-glutathione (GSH) increased. These above results indicated that Zhibai Dihuang decotion can regulate the level of oxidative stress in the body and inhibit osteoclast activity, which played a therapeutic role in PMOP, as well as provided theoretical basis for the prevention and treatment of PMOP with traditional Chinese medicine.

8.
Int J Biol Macromol ; 217: 171-179, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-35835299

RESUMO

Abundant cellulose and insoluble protein were contained in the Se-enriched peanut leaf residue, a by-product from leaf protein extraction. Ionic liquids (ILs) were used to extract the cellulose-protein complexes (CPCs) from Se-enriched peanut leaf residue. The effects of various ILs as extractants and organic solvents as regenerant on the physicochemical properties of CPCs were compared. The results showed that the yield of CPCs and recovery yield of [AMIM]Cl (1-allyl-3-methylimidazole chloride) were better than those of [BMIM]Cl (1-butyl-3-methylimidazolium chloride). Simultaneously, it could be seen from the infrared absorption peaks and secondary structure fitting results that [BMIM]Cl seemed stronger than [AMIM]Cl in destroying the secondary structure of CPCs. Scanning electron microscope (SEM) showed that the CPCs extracted by [BMIM]Cl were lamellate with holes on the surface, and the CPCs extracted by [AMIM]Cl were rough, almost without holes on the surface. Furthermore, the transmittance and tensile strength of the film which contained BA-CPC ([BMIM]Cl as extractant and acetonitrile as regenerant) film were better than those contained AA-CPC ([AMIM]Cl as extractant and acetonitrile as regenerant) film, which might be mainly because the types of ILs and regenerants affect the particle size of CPCs, thereby influencing the mechanical properties of the film.


Assuntos
Líquidos Iônicos , Acetonitrilas , Arachis/metabolismo , Celulose/química , Líquidos Iônicos/química , Folhas de Planta/metabolismo , Solventes/química
9.
Genes (Basel) ; 13(6)2022 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-35741702

RESUMO

Recently, we have seen a growing volume of evidence linking the microbiome and human diseases or clinical outcomes, as well as evidence linking the microbiome and environmental exposures. Now comes the time to assess whether the microbiome mediates the effects of exposures on the outcomes, which will enable researchers to develop interventions to modulate outcomes by modifying microbiome compositions. Use of distance matrices is a popular approach to analyzing complex microbiome data that are high-dimensional, sparse, and compositional. However, the existing distance-based methods for mediation analysis of microbiome data, MedTest and MODIMA, only work well in limited scenarios. PERMANOVA is currently the most commonly used distance-based method for testing microbiome associations. Using the idea of inverse regression, here we extend PERMANOVA to test microbiome-mediation effects by including both the exposure and the outcome as covariates and basing the test on the product of their F statistics. This extension of PERMANOVA, which we call PERMANOVA-med, naturally inherits all the flexible features of PERMANOVA, e.g., allowing adjustment of confounders, accommodating continuous, binary, and multivariate exposure and outcome variables including survival outcomes, and providing an omnibus test that combines the results from analyzing multiple distance matrices. Our extensive simulations indicated that PERMANOVA-med always controlled the type I error and had compelling power over MedTest and MODIMA. Frequently, MedTest had diminished power and MODIMA had inflated type I error. Using real data on melanoma immunotherapy response, we demonstrated the wide applicability of PERMANOVA-med through 16 different mediation analyses, only 6 of which could be performed by MedTest and 4 by MODIMA.


Assuntos
Microbiota , Exposição Ambiental , Humanos , Projetos de Pesquisa
10.
Bioinformatics ; 38(12): 3173-3180, 2022 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-35512399

RESUMO

MOTIVATION: Understanding whether and which microbes played a mediating role between an exposure and a disease outcome are essential for researchers to develop clinical interventions to treat the disease by modulating the microbes. Existing methods for mediation analysis of the microbiome are often limited to a global test of community-level mediation or selection of mediating microbes without control of the false discovery rate (FDR). Further, while the null hypothesis of no mediation at each microbe is a composite null that consists of three types of null, most existing methods treat the microbes as if they were all under the same type of null, leading to excessive false positive results. RESULTS: We propose a new approach based on inverse regression that regresses the microbiome data at each taxon on the exposure and the exposure-adjusted outcome. Then, the P-values for testing the coefficients are used to test mediation at both the community and individual taxon levels. This approach fits nicely into our Linear Decomposition Model (LDM) framework, so our new method LDM-med, implemented in the LDM framework, enjoys all the features of the LDM, e.g. allowing an arbitrary number of taxa to be tested simultaneously, supporting continuous, discrete, or multivariate exposures and outcomes (including survival outcomes), and so on. Using extensive simulations, we showed that LDM-med always preserved the FDR of testing individual taxa and had adequate sensitivity; LDM-med always controlled the type I error of the global test and had compelling power over existing methods. The flexibility of LDM-med for a variety of mediation analyses is illustrated by an application to a murine microbiome dataset, which identified several plausible mediating taxa. AVAILABILITY AND IMPLEMENTATION: Our new method has been added to our R package LDM, which is available on GitHub at https://github.com/yijuanhu/LDM. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Microbiota , Camundongos , Animais , Modelos Lineares , Projetos de Pesquisa
11.
Genes Dev ; 36(7-8): 408-413, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35393344

RESUMO

Chaperones influence histone conformation and intermolecular interaction in multiprotein complexes, and the structures obtained with full-length histones often provide more accurate and comprehensive views. Here, our structure of the Hat1-Hat2 acetyltransferase complex bound to Asf1-H3-H4 shows that the core domains of H3 and H4 are involved in binding Hat1 and Hat2, and the N-terminal tail of H3 makes extensive interaction with Hat2. These findings expand the knowledge about histone-protein interaction and implicate a function of Hat2/RbAp46/48, which is a versatile histone chaperone found in many chromatin-associated complexes, in the passing of histones between chaperones.


Assuntos
Histona Acetiltransferases , Histonas , Acetilação , Proteínas de Ciclo Celular/metabolismo , Cromatina , Histona Acetiltransferases/metabolismo , Chaperonas de Histonas/metabolismo , Histonas/metabolismo , Chaperonas Moleculares/genética
12.
Int Immunopharmacol ; 108: 108678, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35364431

RESUMO

Aryl hydrocarbon receptor (Ahr) is thought to be a crucial factor that regulates immune responses, which may be involved in the pathogenesis of autoimmune inflammation including rheumatoid arthritis (RA). The results of our group in recent years have shown that Paeoniflorin-6'-O-benzene sulfonate (code: CP-25), a novel ester derivative of paeoniflorin, has a good effect on improving RA animal models. However, whether the anti-arthritis effect of CP-25 is related to Ahr remains unclear. Here, we showed that CP-25 treatment ameliorated adjuvant-induced arthritis (AA), a rat model of RA, by inhibiting Ahr-related activities in fibroblasts like synoviocytes (FLS). AA rats were treated with CP-25 or paroxetine from days 17 to 33 after immunization. We showed that CP-25 alleviated arthritis symptoms and the pathological changes. Treatment with CP-25 decreased the expression of Ahr in the synovium of AA rats. CP-25 inhibited the expression of Ahr and the G protein-coupled receptor kinase 2 (GRK2) as well as the co-expression of GRK2 with Ahr in FLS of AA rats. Furthermore, CP-25 down-regulated the production of Kyn in FLS of AA rats. These results suggested that CP-25 may inhibit the expression and activation of Ahr. Besides, treatment with CP-25 reduced the proliferation and migration of MH7A caused by Ahr activation. In addition, we also demonstrated that CP-25 down-regulated the total and nuclear expression of Ahr and the expression of GRK2 in Kyn-treated MH7A. Moreover, the co-expression and co-localization of Ahr and GRK2in Kyn-treated MH7A were also repressed by CP-25. The data presented here demonstrated that CP-25 suppressed FLS dysfunction in rats with AA, which were associated with reduced Ahr activation and the interaction between Ahr and GRK2.


Assuntos
Artrite Experimental , Artrite Reumatoide , Sinoviócitos , Animais , Artrite Experimental/patologia , Artrite Reumatoide/metabolismo , Proliferação de Células , Células Cultivadas , Fibroblastos , Glucosídeos , Monoterpenos , Ratos , Receptores de Hidrocarboneto Arílico/metabolismo , Membrana Sinovial/patologia
13.
Front Plant Sci ; 13: 1082926, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36762176

RESUMO

Low temperature delayed cotton growth, increased abscission of reproductive organs, and seriously reduced quality and yield. Moreover, failed or unstable performance of insecticidal resistance due to adverse environments have been reported. In order to study the impact of low temperature on the insecticidal protein contents at square stage in Bacillus Thuringenesis (Bt) transgenic cotton, different temperature regimes and durations were imposed on two Bt cotton cultivars, Sikang1 (the conventional cultivar, SK1) and Sikang3 (the hybrid cultivar, SK3). Low temperature stress exhibited a significant inhibitory effect on insecticidal protein expression in squares and leaves of Bt transgenic cotton plants, with insecticidal protein contents decreased up to 30% with decreasing temperature. In addition, the threshold temperature resulting in significant reduction of insecticidal protein contents symbolized a rising trend as stress duration extended, together with a greater reduction observed. Thus, at square stage, the detrimental influence of low temperature on Bt protein contents was closely related to the low temperature level and duration. The square Bt protein content was positively correlated with leaf Bt protein content, but was more sensitive to low temperature. Across the whole treatment duration in both years, square Bt protein level was significantly negatively correlated with malondialdehyde (MDA) contents, as well as the activities of catalase (CAT) and superoxide dismutase (SOD), indicating the negative effect of cold induced oxidative stress on Bt protein contents. The reduced Bt protein contents under low temperature were also related to altered N metabolism. Glutamate oxaloacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT) activities, as well as soluble protein contents in squares reduced, and greater reduction was recorded with decreasing temperature. In contrast, the free amino acid contents, and peptidase and protease activities increased, and greater elevation was noted with decreasing temperature. These results suggested in Bt cotton production, it is necessary to be alert to low temperature disasters that may last for more than 24 hours and lower than 15-17°C during the square stage, which may lead to reduced insecticidal resistance causing serious economic losses.

14.
Chinese Pharmacological Bulletin ; (12): 1176-1182, 2022.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1014031

RESUMO

Aim To observe the therapeutie effeet of (AA) rats and its effect on the aetivity of tryptophan allopurinol ( ALLO) on adjuvant induced arthritis 2,3 dioxygenase (TDO).Methods SD rats were randomly divided into normal group, AA model group, ALLO group (10,20 , 40 mg • kg 1 ) and methotrexate group (0.5 mg • kg 1 ).The AA rats were established by intracutaneous injection of complete Freund's adju¬vant into the right toes of rats.The body weight,joint swelling number, joint pathology, spleen index and fi¬broblast like synoviocytes ( FLS) proliferation of the rats were observed to explore the therapeutic effect of ALLO.Flow cytometry detected the number of CD68 ∗ macrophages and the ratio of Thl7/Treg of spleen.The concentration of tryptophan ( Trp) and kvnurenine ( Kyn) in the liver and the supernatant of FLS were de¬termined by high performance liquid chromatography.Results Compared with model group, ALLO adminis¬ tration significantly increased the body weight of AA rats, reduced the number of joint swelling, improved joint pathological injury,decreased spleen index,inhib¬ited the proliferation of FLS, reduced the number of macrophages in the spleen,decreased Thl7/Treg ratio, inhibited the metabolism of Tip and the production of Kyn in liver and FLS culture supernatant, and de¬creased the liver Kyn/Trp ratio (TOO activity).Con¬clusion ALLO has therapeutic effect on AA rats, which may be related to its regulation of TDO-mediated kyn metabolism pathway.

15.
Water Res ; 203: 117562, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34428696

RESUMO

Unraveling the transformation of coagulants and their interaction with contaminants at the micro-level is vital to advancing our understanding of the coagulation mechanism. To the best of our knowledge, the coagulation effectiveness of [AlO4Al12(OH)24(H2O)12]7+ (Al13), regarded as the dominant species in polyaluminum chloride (PACl), is highly related to its aggregation characteristic, but the detailed process of Al13 aggregation in coagulation time scale was not well studies. Here we systematically studied the deprotonation and aggregation processes of Al13 by alkaline titration to simulate the reaction in coagulation case. By reacting with OH-, Al13 can continuously lose protons regardless of pH until its positive charge was well neutralized. The initial Al13 aggregates (Al13agg) appeared at B of 2.70 and large Al13agg was generated by coalescence of small initial Al13agg. Most Al13 polycations kept their main structure unchanged during aggregation and part was decomposed into monomers or oligomers. Density functional theory (DFT) results reveal that Al13 becomes unstable after deprotonation, but the aggregation of Al13 bridged by Al monomers can stabilize the polycations. Al13 needs to be hydrolyzed before interacting with colloidal particles, but particles can promote the aggregation of Al13 by weakening the repulsion force between the polymers. Strong and compact flocs can be generated induced by in-situ aggregation of Al13 in neutral and alkaline conditions. This study can provide a deep understanding about the role of Al13agg in removing particles and instruct the development of new efficient coagulants against the various water qualities.


Assuntos
Purificação da Água , Alumínio , Hidróxido de Alumínio , Polímeros
16.
Chemosphere ; 278: 130493, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34126694

RESUMO

Al30 is the polycation with the highest degree of polymerization and surface charge in the currently known structural aluminum species. It shows excellent coagulation performance in water treatment process, and has the characteristics of wide application range of pH and dosage. pH value is one of the most important factors affecting the aggregation and coagulation process of Al30, but the influence of Al30 aggregation reaction on its coagulation effect is still unclear. Therefore, this article reports the deprotonation and aggregation reaction of Al30 by adjusting the basicity (B) of the solution, particularly to further understand the coagulation mechanism of Al30 under different conditions. The results showed that in the base titration process, when B < 2.86 in 0.01 M Al30 solution as AlT (the concentration of total Al), deprotonation and preliminary aggregation mainly occurred; when B > 2.86, the size of Al30 aggregates (Al30agg) increased rapidly, forming gels and gradually transforming into Al(OH)3. In this process, in addition to the reduction of electrostatic repulsion induced by Al30 deprotonation, the oligomers generated by the partial dissociation of Al30 also play the role of bridging-connection. Under the experimental titration conditions, the Al30agg always maintained a positive zeta potential. In addition, Al30 can deprotonate and aggregate at lower pH, which is an important reason for its unique coagulation characteristics. The larger structure size of Al30 also made it easy to form branched aggregates, so that it can play an effective role in a wider dosage range without destabilization of colloids. This study gives an insight in the advancement of coagulants and promotes the industrial application and commercialization of functional coagulants based on polyaluminum.


Assuntos
Purificação da Água , Alumínio , Hidróxido de Alumínio , Floculação
17.
PeerJ ; 9: e11406, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34026361

RESUMO

BACKGROUND: There are about 15 million Americans working full-time on evening, night, or rotating shifts. Between 48% and 81.9% of those working rotating or night shifts report abdominal pain, constipation, diarrhea and other symptoms of functional bowel disorders. The basis for this high prevalence of functional bowel disorders, including irritable bowel syndrome (IBS), among shift workers is unknown. Animal studies, however, suggest that circadian disruption, similar to that in shift workers, may contribute to the development of GI complaints among shift workers by altering the composition and normal diurnal rhythmicity of the resident intestinal microbes. Therefore, the present study was designed to determine if there were differences in (1) composition and diversity of the microbiome of night shift workers compared to day shift workers; and (2) the composition and diversity of the microbiome among shift workers experiencing functional bowel symptoms compared to shift workers who did not experience functional bowel symptoms. METHODS: Fifty-one full time staff nurses who worked either 12-hour day or night shifts completed demographic information, and the Rome III IBS module. They also collected two samples of gut microbiota before the beginning and at the end of their last work shift on day 14, using validated field-tested methods consistent with the Human Microbiome Project. After DNA extraction, 16S rRNA sequencing and assignment to the genus level was completed, samples were then compared to determine if there were (1) differences in the diversity and profile of the microbiome by shift type; (2) if there were differences in the microbiome by time of day for collection; and (3) whether there were differences in the diversity and profile of the microbiome of nurses with IBS and those without IBS. RESULTS: There were no differences in alpha or beta diversity of gut microbiota when specimens from day and night shift nurses were compared. There were however marginal differences in beta diversity when specimens collected at the beginning and end of the shifts were compared, with seven OTUs being differentially abundant when collected from day shift workers in the evening. There were also three OTUs to be differentially abundant in participants reporting IBS symptoms.

18.
Chemosphere ; 277: 130268, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33774233

RESUMO

The effective removal of humic acid (HA) by coagulation has been extensively investigated for water treatments. However, the limitations of pH variation and excessive residual aluminum issues were still factors needed to be considered. In this study, to investigate the coagulation mechanism for removing HA by Al13 and optimize Al13 operation for removing HA, Al13 and preformed Al13 aggregates (Al13agg) were applied to remove HA at different pH conditions. The results showed that preformed Al13agg exhibited superior HA removal performance than Al13 due to its wide pH range and low residual Al level. During coagulation, Al13 and Al13agg interacted with HA in their original status, but the DSlope325-375 difference implied that the complexation capacity between HA and Al13agg was stronger than Al13. The new peaks of HPSEC representing larger molecular weight substances were formed under acidic and neutral conditions, which indicated that HA firstly aggregated into larger complexed molecules by interacting with Al13 or its hydrolysates and was subsequently removed by forming large flocs which was completely different from Al13agg situation. Therefore, the different coagulation mechanisms played the roles in HA removal for Al13 and Al13agg which were studied in this paper. It was believed that the complexation and charge neutralization effects dominated coagulation process for Al13 while sweep flocculation and adsorption coagulation were main driving force for Al13agg in HA removing. This work provides significant understanding of HA removal by Al13 and Al13agg coagulation, which can help to design and optimize the high efficiency coagulant based on Al polycations.


Assuntos
Substâncias Húmicas , Purificação da Água , Alumínio , Hidróxido de Alumínio , Floculação , Substâncias Húmicas/análise , Polímeros
19.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-909615

RESUMO

OBJECTIVE Aryl hydrocarbon receptor (Ahr) is thought to be a crucial factor that regulates immune responses, which may be involved in the pathogenesis of autoimmune inflammation including rheumatoid arthritis (RA). The results of our group in recent years have shown that CP-25, a novel ester derivative of paeoniflorin, has a good effect on improving RA animal models. However, whether the anti-arthritis effect of CP-25 is related to Ahr remains unclear. METHODS CP-25 treatment ameliorated adjuvant-induced arthritis (AA), a mouse model of RA, by inhibiting Ahr-related activities in fibroblasts like synoviocytes (FLS). AA rats were treated with CP-25 or paroxetine from day 17 to 33 after immunization. RESULTS CP-25 alleviated arthritis symptoms and the pathological changes, decreased the expression of Ahr in the synovium and FLS of AA rats. Besides, treatment with CP-25 reduced the proliferation and migration of MH7A caused by Ahr activation. In addition, we also demonstrated that CP-25 down-regulated the co-expres?sion and co-localization of Ahr and G protein-coupled receptor kinase 2 (GRK2) in MH7A. CONCLUSION The data pre?sented here demonstrated that CP-25 suppressed FLS dysfunction in rats with AA, which were associated with reduced Ahr activation and the interaction between Ahr and GRK2.

20.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-882625

RESUMO

Objective:To observe the clinical efficacy of Dushen Decoction and Zhenwu Decoction in the treatment of chronic congestive heart failure (CCHF) of Yang deficiency and blood stasis type. Methods:From March 2017 to December 2019, 120 patients with CCHF of Yang-deficiency and blood stasis type admitted to Shanghai Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine were selected, and they were divided into study group and control group according to the randomized number table method, with 60 in each group. The control group was given western medicine of conventional treatment, and the study group was combined with Dushen Decoction and Zhenwu Decoction on the basis of the control group. Both groups were treated for 1 month. Before and after treatment, TCM syndrome scores were performed, serum TNF-α, IL-17 and CRP were detected by ELISA, left ventricular ejection fraction (LVEF), left ventricular end diastolic diameter (LVEDD) and left ventricular end systolic diameter (LVESD) were detected by color doppler echocardiography the adverse reactions during the treatment were recorded and the clinical efficacy was evaluated. Results:The total effective rate was 91.7% (55/60) in the study group and 71.7% (43/60) in the control group, with significant difference between the two groups ( χ2=8.015, P=0.005). After treatment, the scores of palpitation, dyspnea, chilly limbs, dull tongue and edema in the study group were significantly lower than those in the control group ( t=13.953, 13.915, 30.945, 32.339, 20.403, P<0.001). After treatment, LVEF [(56.28 ± 4.34)% vs. (42.47 ± 4.56)%, t=16.993] in the study group was significantly higher than that of the control group ( P<0.01); LVEDD [(44.32 ± 6.23) mm vs. (53.81 ± 5.19) mm, t=9.066] and LVESD [(31.28 ± 4.62) mm vs. (37.51 ± 4.73) mm, t=7.299] in the study group were significantly lower than those in the control group ( P<0.01). After treatment, the serum levels of TNF-α, IL-17 and CRP in the study group were significantly lower than those in the control group ( t=12.644, 15.975 and 14.379, P<0.001). The incidence of adverse reactions was 6.7% (4/60) in the control group and 8.3% (5/60) in the study group, and there was no significant difference between the two groups ( χ2=0.120, P=0.729). Conclusion:Dushen Decoction and Zhenwu Decoction in the treatment of CCHF can improve the clinical symptoms, improve the cardiac function, reduce inflammatory factors, improve the treatment efficiency with good safety.

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