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SETTING: Previous studies addressed the association between anti-thyroid antibodies and recurrent miscarriage (RM), however, the role of anti-thyroid antibodies in RM patients is debatable. OBJECTIVES: Therefore, we conducted this meta-analysis and the aim of this current study was to assess whether anti-thyroid peroxidase (anti-TPO) and/or anti-thyroglobulin (anti-TG) antibody positivity was associated with RM. DESIGN: A meta-analysis was conducted. PARTICIPANTS: Recurrent miscarriage patients. METHODS: STATA 12.0 software were applied to compute odds ratios (ORs)/relative risks (RRs) and 95% CIs regarding association between anti-TPO and anti-TG antibodies and the prevalence of RM. RESULTS: N = 28 studies (8875 participants) explored effect of anti-thyroid antibodies on RM. Analysis of the 28 studies revealed significant association between anti-TPO, anti-TG antibodies and the prevalence of RM with a random effects model (OR/RR = 2.02; 95% CI: 1.63-2.51, p < 0.001; I2 = 44.3%, p value for Q test = 0.004). Analysis of the 20 studies revealed significant association between anti-TPO antibodies and the prevalence of RM with a random effects model (OR/RR = 1.59; 95% CI: 1.25-2.03, p < 0.001; I2 = 43.1%, p value for Q test = 0.022). Analysis of the 14 studies revealed significant association between anti-TG antibodies and the prevalence of RM with a random effects model (OR/RR = 2.25; 95% CI: 1.56-3.23, p < 0.001; I2 = 49.2%, p value for Q test = 0.019). CONCLUSIONS: Based on the currently available analysis, our findings suggest that women with anti-TPO and/or anti-TG antibodies have a higher risk of RM than that in negative antibody women. Further investigation is needed to better clarify the exact role of the anti-thyroid antibodies in RM and whether treatment is of benefit. LIMITATIONS: First, differences from various detection methods and reagents used in different studies may affect the diagnostic interpretation of anti-thyroid antibodies, which might influence the accuracy of this meta-analysis. Second, positive anti-thyroid antibodies seem likely to be part of a more general disorder of maternal immune system, due to restrictions of funding and condition, a complete autoantibody screening investigation is hardly to conduct in all participants, and this could be a possible limitation of all included studies. Third, there is no mention of thyroxine therapy on RM, making the meta-analysis even more limited.
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Aborto Habitual , Autoanticorpos , Iodeto Peroxidase , Humanos , Aborto Habitual/imunologia , Feminino , Autoanticorpos/sangue , Gravidez , Iodeto Peroxidase/imunologia , Tireoglobulina/imunologiaRESUMO
BACKGROUND: The use of synbiotics is emerging as a promising intervention strategy for regulating the gut microbiota and for preventing or reducing obesity, in comparison with the use of probiotics or prebiotics alone. A previous in vivo study revealed that Lacticaseibacillus paracasei K56 (L. paracasei K56) could alleviate obesity induced in high-fat-diet mice; however, the effect of the synbiotic combination of L. paracasei K56 and prebiotics in obese individuals has not been explored fully. RESULTS: The effect of prebiotics on the proliferation of L. paracasei K56 was determined by spectrophotometry. The results showed that polydextrose (PG), xylooligosaccharide (XOS), and galactooligosaccharide (GOS) had a greater potential to be used as substrates for L. paracasei K56 than three other prebiotics (melitose, stachyose, and mannan-oligosaccharide). An in vitro fermentation model based on the feces of ten obese female volunteers was then established. The results revealed that K56_GOS showed a significant increase in GOS degradation rate and short-chain fatty acid (SCFA) content, and a decrease in gas levels, compared with PG, XOS, GOS, K56_PG, and K56_XOS. Changes in these microbial biomarkers, including a significant increase in Bacteroidota, Bifidobacterium, Lactobacillus, Faecalibacterium, and Blautia and a decrease in the Firmicutes/Bacteroidota ratio and Escherichia-Shigella in the K56_GOS group, were associated with increased SCFA content and decreased gas levels. CONCLUSION: This study demonstrates the effect of the synbiotic combination of L. paracasei K56 and GOS on obese individuals and indicates its potential therapeutic role in obesity treatment. © 2024 Society of Chemical Industry.
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Fermentação , Microbioma Gastrointestinal , Lacticaseibacillus paracasei , Obesidade , Oligossacarídeos , Simbióticos , Humanos , Obesidade/metabolismo , Obesidade/microbiologia , Obesidade/dietoterapia , Simbióticos/administração & dosagem , Oligossacarídeos/metabolismo , Oligossacarídeos/administração & dosagem , Feminino , Adulto , Lacticaseibacillus paracasei/metabolismo , Fezes/microbiologia , Fezes/química , Prebióticos/análise , Probióticos/administração & dosagem , Adulto Jovem , Pessoa de Meia-IdadeRESUMO
BACKGROUND: The basic leucine zipper (bZIP) transcription factor family is one of the most abundant and evolutionarily conserved gene families in plants. It assumes crucial functions in the life cycle of plants, including pathogen defense, secondary metabolism, stress response, seed maturation, and flower development. Although the genome of wax gourd has been published, little is known about the functions, evolutionary background, and gene expression patterns of the bZIP gene family, which limits its utilization. RESULTS: A total of 61 bZIP genes (BhbZIPs) were identified from wax gourd (Benincasa hispida) genome and divided into 12 subgroups. Whole-genome duplication (WGD) and dispersed duplication (DSD) were the main driving forces of bZIP gene family expansion in wax gourd, and this family may have undergone intense purifying selection pressure during the evolutionary process. We selected BhbZIP58, only one in the member of subgroup B, to study its expression patterns under different stresses, including heat, salt, drought, cold stress, and ABA treatment. Surprisingly, BhbZIP58 had a dramatic response under heat stress. BhbZIP58 showed the highest expression level in the root compared with leaves, stem, stamen, pistil, and ovary. In addition, BhbZIP58 protein was located in the nucleus and had transcriptional activation activity. Overexpression of BhbZIP58 in Arabidopsis enhanced their heat tolerance. CONCLUSIONS: In this study, bZIP gene family is systematically bioinformatically in wax gourd for the first time. Particularly, BhbZIP58 may have an important role in heat stress. It will facilitate further research on the bZIP gene family regarding their evolutionary history and biological functions.
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Perfilação da Expressão Gênica , Genoma de Planta , Genes de Plantas , Família Multigênica , Resposta ao Choque Térmico/genética , Filogenia , Regulação da Expressão Gênica de Plantas , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Estresse Fisiológico/genéticaRESUMO
1. The pharmacokinetics (PKs) analysis of compounds absorbed after the oral administration of Si-Ni-San (SNS) decoction to functional dyspepsia (FD) patients was designed to detect whether the effects were similar to prokinetics administered to healthy rats, without ethical limitation. 2. First, the absorbed compounds, liquiritigenin (L), naringenin (N) and hesperitin (H) in the plasma were identified by UPLC-MS/MS following the oral administration of SNS decoction to subjects with FD. Next, the natural ratio of LNH in the SNS decoction was determined by UPLC. Third, gastric emptying and intestinal transit after the oral administration of LNH, in combination or alone, was compared with those observed after SNS administration in healthy rats. Additionally, the clinical PKs of LNH was studied. 3. The prokinetic efficacy of LNH administered at their natural ratios (7.5:5:1) increased dose-dependently and was better than the observed efficacy when administered alone in rats. Analysis of the clinical PK parameters, calculated using a one-compartment model, showed that the Cmax parameters of LNH in 3, 4 and 4 h were 639.17, 410.00 and 181.67 µg/L, respectively. 4. The clinical herbal PK analysis of the absorbed LNH preclinical prokinetic compounds, in their natural ratio from SNS, highlights the impact of an herbal translational pharmacology study.
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Medicamentos de Ervas Chinesas/uso terapêutico , Dispepsia/tratamento farmacológico , Flavanonas/farmacocinética , Hesperidina/farmacocinética , Administração Oral , Adulto , Cromatografia Líquida , Medicamentos de Ervas Chinesas/administração & dosagem , Feminino , Flavanonas/sangue , Flavanonas/química , Motilidade Gastrointestinal/efeitos dos fármacos , Hesperidina/sangue , Hesperidina/química , Humanos , Masculino , Pessoa de Meia-Idade , Sulfametoxazol/químicaRESUMO
Bifidobacterium longum subsp. infantis YLGB-1496 (YLGB-1496) is a probiotic strain isolated from human breast milk. The application of YLGB-1496 is influenced by carbohydrate utilization and genetic stability. This study used genome sequencing and morphology during continuous subculture to determine the carbohydrate utilization characteristics and genetic stability of YLGB-1496. The complete genome sequence of YLGB-1496 consists of 2,758,242 base pairs, 2442 coding sequences, and a GC content of 59.87%. A comparison of carbohydrate transport and metabolism genes of Bifidobacterium longum subsp. infantis (B. infantis) showed that YLGB-1496 was rich in glycosyl hydrolase 13, 20, 25, and 109 gene families. During continuous subculture, the growth characteristics and fermentation activity of the strain were highly stable. The bacterial cell surface and edges of the 1000th-generation strains were progressively smoother and well-defined, with no perforations or breaks in the cell wall. There were 20 SNP loci at the 1000th generation, fulfilling the requirement of belonging to the same strain. The presence of genes associated with cell adhesion and the absence of resistance genes supported the probiotic characteristics of the strain. The data obtained in this study provide insights into broad-spectrum carbohydrate utilization, genomic stability, and probiotic properties of YLGB-1496, which provide theoretical support to promote the use of YLGB-1496.
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Bifidobacterium , Metabolismo dos Carboidratos , Genoma Bacteriano , Bifidobacterium/genética , Bifidobacterium/metabolismo , Metabolismo dos Carboidratos/genética , Humanos , Probióticos , Instabilidade Genômica , Bifidobacterium longum subspecies infantis/genética , Bifidobacterium longum subspecies infantis/metabolismoRESUMO
Ligustilide (LIG) is the main active ingredient of Angelica sinensis (Oliv.) Diels, which could promote focal angiogenesis to exert neuroprotection. However, there was no report that verified the exact effects of LIG on endometrial angiogenesis and the pregnancy outcomes. To explore the effects of LIG on low endometrial receptivity (LER) and angiogenesis, pregnancy rats were assigned into Control (saline treatment), LER (hydroxyurea-adrenaline treatment), LIG 20 mg/kg and LIG 40 mg/kg groups. Hematoxylin and eosin (H&E) staining was performed to evaluate endometrial morphology. Quantitative real-time PCR, immunofluorescence staining, western blot and immunohistochemistry staining were employed to assess the expression of endometrial receptivity factors and angiogenesis-related gene/protein, respectively. RNA sequencing was used to analyze the effects of LIG on LER caused by Kidney deficiency and blood stasis. We found that endometrial thickness and the implanted embryo number were substantially reduced in the hydroxyurea-adrenaline-treated pregnancy rats. At the same time, the gene and protein expressions of ERα, LIF, VEGFA and CD31 in the endometrium were markedly reduced, while the expressions of MUC1, E-cadherin were increased in the LER group. Administration of LIG raised the endometrial thickness and implanted embryos, as well as reversed the expressions of these factors. Collectively, our findings revealed that LIG could facilitate embryo implantation via recovery of the endometrium receptivity and promotion of endometrial angiogenesis.
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Hidroxiureia , Resultado da Gravidez , Gravidez , Feminino , Ratos , Animais , Hidroxiureia/metabolismo , Hidroxiureia/farmacologia , Angiogênese , Endométrio/metabolismo , Epinefrina/metabolismo , Epinefrina/farmacologiaRESUMO
Chieh-qua is an important cucurbit crop and very popular in South China and Southeast Asia. Despite its significance, its genetic basis and domestication history are unclear. In this study, we have successfully generated a chromosome-level reference genome assembly for the chieh-qua 'A36' using a hybrid assembly strategy that combines PacBio long reads and Illumina short reads. The assembled genome of chieh-qua is approximately 953.3 Mb in size and is organized into 12 chromosomes, with contig N50 of 6.9 Mb and scaffold N50 of 68.2 Mb. Notably, the chieh-qua genome is comparable in size to the wax gourd genome. Through gene prediction analysis, we have identified a total of 24 593 protein-coding genes in the A36 genome. Additionally, approximately 56.6% (539.3 Mb) of the chieh-qua genome consists of repetitive sequences. Comparative genome analysis revealed that chieh-qua and wax gourd are closely related, indicating a close evolutionary relationship between the two species. Population genomic analysis, employing 129 chieh-qua accessions and 146 wax gourd accessions, demonstrated that chieh-qua exhibits greater genetic diversity compared to wax gourd. We also employed the GWAS method to identify related QTLs associated with subgynoecy, an interested and important trait in chieh-qua. The MYB59 (BhiCQ0880026447) exhibited relatively high expression levels in the shoot apex of four subgynoecious varieties compared with monoecious varieties. Overall, this research provides insights into the domestication history of chieh-qua and offers valuable genomic resources for further molecular research.
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Current treatment for functional dyspepsia (FD) has limited and unsustainable efficacy. Probiotics have the sustainable potential to alleviate FD. This randomized controlled clinical trial (Chinese Clinical Trial Registry, ChiCTR2000041430) assigned 200 FD patients to receive placebo, positive-drug (rabeprazole), or Bifidobacterium animalis subsp. lactis BL-99 (BL-99; low, high doses) for 8-week. The primary outcome was the clinical response rate (CRR) of FD score after 8-week treatment. The secondary outcomes were CRR of FD score at other periods, and PDS, EPS, serum indicators, fecal microbiota and metabolites. The CRR in FD score for the BL-99_high group [45 (90.0%)] was significantly higher than that for placebo [29 (58.0%), p = 0.001], BL-99_low [37 (74.0%), p = 0.044] and positive_control [35 (70.0%), p = 0.017] groups after 8-week treatment. This effect was sustained until 2-week after treatment but disappeared 8-week after treatment. Further metagenomic and metabolomics revealed that BL-99 promoted the accumulation of SCFA-producing microbiota and the increase of SCFA levels in stool and serum, which may account for the increase of serum gastrin level. This study supports the potential use of BL-99 for the treatment of FD.
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Bifidobacterium animalis , Dispepsia , Probióticos , Humanos , Dispepsia/terapia , Probióticos/uso terapêutico , Fezes/microbiologia , Método Duplo-CegoRESUMO
BACKGROUND: Women with antiphospholipid syndrome (APS) or antiphospholipid antibodies (aPLs) are at high risk for obstetric complications, including recurrent pregnancy loss (RPL). However, effective treatments for RPL are lacking. OBJECTIVE: This study aimed to reveal the function and underlying mechanism of hyperoside (Hyp) in RPL associated with antiphospholipid antibodies (aCLs). METHODS: The pregnant rats (N = 24) were divided randomly into four groups: normal human-IgG (NH-IgG); aCL-pregnancy loss (aCL-PL); aCL-PL + Hyp (40 mg/kg/day); aCL-PL + low molecular weight heparin (LMWH, 525 µg/kg/day). HTR-8 cells were treated with 80 µg/mL aCL to establish the cell models of miscarriage. RESULTS: In pregnant rats, aCL-IgG injection raised the abortion rate of embryos, while Hyp treatment inhibited the effects. Additionally, Hyp inhibited the platelet activation and uteroplacental insufficiency caused by aCL. In vivo and in vitro experiments further suggested that Hyp suppressed aCL-induced inflammation and apoptosis by downregulating NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome-related factors and decreasing apoptotic rates. After aCL administration, Hyp therapy downregulated the expression of purinergic ligand-gated ion channel 7 (P2X7), which is reported to induce cytokine release and apoptosis. Furthermore, we found that the treatment of 3'-O-(4-Benzoyl) benzoyl-ATP (BzATP, an agonist of the P2X7 receptor) reversed the inhibitory effects of Hyp on cell function. CONCLUSIONS: Hyp exerts protective effects on aCL-induced pregnancy loss by preventing platelet activation-mediated P2X7/NLRP3 pathway. Therefore, Hyp may provide a feasible pharmaceutical strategy for the treatment of RPL.
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Aborto Habitual , Anticorpos Anticardiolipina , Gravidez , Feminino , Humanos , Ratos , Animais , Heparina de Baixo Peso Molecular , Proteína 3 que Contém Domínio de Pirina da Família NLR , Anticorpos Antifosfolipídeos , Aborto Habitual/etiologia , Aborto Habitual/prevenção & controle , Imunoglobulina GRESUMO
Probiotics could improve cognitive functions in patients with neurological disorders such as Alzheimer's disease, but the effects on cognitive function in healthy older adults without cognitive impairment need further study. The purpose of this study was to investigate the effect of Bifidobacterium longum BB68S (BB68S) on cognitive functions among healthy older adults without cognitive impairment. A randomized, double-blind, placebo-controlled trial was conducted with 60 healthy older adults without cognitive impairment who were divided into probiotic or placebo groups and required to consume either a sachet of probiotic (BB68S, 5 × 1010 CFU/sachet) or placebo once daily for 8 weeks. The Montreal Cognitive Assessment (MoCA) was used as an inclusion screening tool to screen elderly participants with healthy cognitive function in our study, and the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) was used to assess cognitive function in subjects before and after intervention as an assessment tool. BB68S significantly improved subjects' cognitive functions (total RBANS score increased by 18.89 points after intervention, p < 0.0001), especially immediate memory, visuospatial/constructional, attention, and delayed memory domains. BB68S intervention increased the relative abundances of beneficial bacteria Lachnospira, Bifidobacterium, Dorea, and Cellulosilyticum, while decreasing those of bacteria related to cognition impairment, such as Collinsella, Parabacteroides, Tyzzerella, Bilophila, unclassified_c_Negativicutes, Epulopiscium, Porphyromonas, and Granulicatella. In conclusion, BB68S could improve cognitive functions in healthy elderly adults without cognitive impairment, along with having beneficial regulatory effects on their gut microbiota. This study supports probiotics as a strategy to promote healthy aging and advances cognitive aging research.
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Bifidobacterium longum , Disfunção Cognitiva , Probióticos , Humanos , Idoso , Probióticos/uso terapêutico , Cognição , Bifidobacterium , Disfunção Cognitiva/terapia , Método Duplo-CegoRESUMO
Lacticaseibacillus casei is used extensively in the fermented milk-beverage industry as a starter culture. Acid production capacity during fermentation is the main criterion for evaluating starters although it is strain-dependent. In this study, the acid production rates of 114 L. casei strains were determined and then classified into high acid (HC), medium acid (MC), and low acid (LC) groups. Comparative genomics analysis found that the lac operon genes encoding the phosphoenolpyruvate-lactose phosphotransferase system (PTSLac) were located on plasmids in the HC strains; however, it is notable that the corresponding operons were located on the chromosome in LC strains. Real-time PCR analysis showed that the copy numbers of lac operon genes in HC strains were between 3.1 and 9.3. To investigate the relationship between copy number and acid production rate, the lac operon cluster of the HC group was constitutively expressed in LC strains. The resulting copy numbers of lac operon genes were between 15.8 and 18.1; phospho-ß-galactosidase activity increased by 1.68-1.99-fold; and the acid production rates increased by 1.24-1.40-fold, which enhanced the utilization rate of lactose from 17.5 to 42.6% in the recombinant strains. The markedly increased expression of lac operon genes increased lactose catabolism and thereby increased the acid production rate of L. casei.
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Chaihu-Shugan-San (CSS), a classic Chinese formula, has long been used to treat depression. For a better and rational use of this formula, here, we investigated the comprehensive pharmacokinetic features of multiple ingredients from CSS using ultra-performance liquid chromatography/quadrupole-time-of-flight mass spectrometry (UPLC-QTOF-MS) in depressed rats. Force swimming experiments were conducted to establish a rat model of depression. Prolonged immobility time, increased plasma adrenocorticotropic hormone, and decreased plasma 5-hydroxytryptamine (5-HT) and dopamine (DA) were confirmed in this model. Nine compounds from CSS, including ferulic acid, naringin, hesperidin, meranzin hydrate, glycyrrhizic acid, saikosaponin A, nobiletin, and hesperetin, were simultaneously determined in plasma samples. Sulfamethoxazole and schisandrin were used as internal standards. The separation was performed on a C18 column with gradient elution over 10â¯min, and detection was executed using multiple reaction monitoring (MRM) in the positive ionization mode. The optimized MRM transitions showed no interference in rat plasma. Validation parameters were all in accordance with the current criterion. The established method was successfully applied to the pharmacokinetic study of these nine components after the oral administration of CSS to depressed rats. This study provides a chemical basis for the clinical application of this formula.
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Antidepressivos/análise , Cromatografia Líquida de Alta Pressão/métodos , Depressão/tratamento farmacológico , Extratos Vegetais/análise , Administração Oral , Animais , Antidepressivos/farmacocinética , Antidepressivos/farmacologia , Modelos Animais de Doenças , Masculino , Espectrometria de Massas , Extratos Vegetais/farmacocinética , Extratos Vegetais/farmacologia , Ratos , Ratos Sprague-DawleyRESUMO
Anticardiolipin antibody (aCL), an important characterization of antiphospholipid syndrome, shows an intense association with vascular endothelial injury. Hyperoside is a flavonoid extracted from medicinal plants traditionally used in Chinese medicines, displaying anti-inflammatory, anti-cancer, and anti-oxidative properties in various diseases. Recent studies have shifted the focus on the protective effects of hyperoside on vascular endothelial injury. However, little is known about the mechanisms involved. In the present study, we investigated the effect of hyperoside on aCL-induced injury of human umbilical vein endothelial cells (HUVECs) in vitro. Our data illustrated that aCL induced HUVEC injury via inhibiting autophagy. Hyperoside reduced aCL-induced secretion of proinflammatory cytokines IL-1ß and IL-8 and endothelial adhesion cytokines TF, ICAM1, and VCAM1 in HUVECs. Additionally, hyperoside activated autophagy and suppressed the mTOR/S6K and TLR4/Myd88/NF-κB signaling transduction pathways in aCL-induced HUVECs. To the best of our knowledge, this is the first study to investigate the effect of hyperoside on aCL-induced injury, as well as offer insights into the involved mechanisms, which is of great significance for the treatment of antiphospholipid syndrome.
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BACKGROUND: Currently, few herbal pharmacokinetic (PK) parameters have been applied successfully for therapeutic monitoring because of the complexity of consistency when there are multiple chemicals and efficacies. PURPOSE: The present study aims to evaluate the herbal PK properties by investigating the PK parameters of the 8 absorbed bioactive compounds (ABCs), which can represent its parent herbal holistic efficacy, to achieve a PK therapeutic monitoring of herbs. METHOD: First, we tested the hypothesis that the antidepressant and prokinetic effects and related anti-inflammation and anti-oxidation activity (APIO) by Fructus aurantii-Magnolia Bark (FM) formula are related to 8 compounds according to the absorbable evidence and the determined contents. Subsequently, stable and representative APIO from 8ABCs allowed us to develop a sensitive and selective liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the simultaneous determination of 8 compounds following the oral administration of FM decoction (20â¯g/kg) in rats. RESULT: 8 compounds either including Meranzin hydrate (MH) or MH alone almost identically (8 compounds: 91.62-108.82%)or nearly(MH: 65.38-88.41%) replicated the parent formula FM in terms of efficacy for inducing APIO. CONCLUSION: This unifying strategy shows how multi-herb formulas pharmacokinetic therapeutic monitoring can be achieved by the method we established.
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Anti-Inflamatórios/farmacocinética , Antidepressivos/farmacocinética , Antioxidantes/farmacocinética , Medicamentos de Ervas Chinesas/química , Magnolia/química , Casca de Planta/química , Animais , Cromatografia Líquida de Alta Pressão/métodos , Cumarínicos/farmacocinética , Medicamentos de Ervas Chinesas/farmacocinética , Frutas/química , Cinética , Masculino , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem/métodosRESUMO
Anaerobic biodegradability of 46 kinds of aromatic compounds was tested and assessed in integrate. These aromatic compounds were classified into readily, partially and poorly biodegradable compounds after their integrated assessment indices (IAI) were calculated. Some rules of anaerobic biodegradation of them were drawn. Stepwise regression and backpropagation artificial neural network (BP-ANN) methods were applied to establish quantitative structure biodegradability relationship (QSBR) based on the assessment results. In QSBR models, five molecular structure descriptors, energy of the highest occupied molecular orbital (EHOMO), total energy (TolE), molar refractivity (MR), the logarithm of the partition coefficient for n-octanol/water (LogP), and standard Gibbs free energy (G), were included. After analyzing the sensitivity of variables in QSBR models, it was found that the key molecular structure descriptors affecting anaerobic biodegradability of aromatic compounds were TolE and MR, which were in direct proportion to the anaerobic biodegradability of aromatic compounds.
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Poluentes Ambientais/metabolismo , Hidrocarbonetos Aromáticos/metabolismo , Redes Neurais de Computação , Bactérias Anaeróbias , Biodegradação Ambiental , Hidrocarbonetos Aromáticos/química , Modelos Teóricos , Análise de RegressãoRESUMO
In this paper, the amount of oxygen consumption, end products and activities of microorganisms are considered as the three factors which affect the biodegradability of organic substances in water. Two integrated assessment methods for biodegradability of organic substances, fuzzy clustering integrated assessment and weighted integrated assessment, have been developed. Simultaneously, the detail steps for assessing a new organic substance biodegradability with these two integrated assessment methods are proposed.
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Bactérias Aeróbias/fisiologia , Modelos Teóricos , Compostos Orgânicos/metabolismo , Poluentes da Água/metabolismo , Biodegradação Ambiental , Lógica Fuzzy , Oxigênio/química , Microbiologia da ÁguaRESUMO
There are various kinds of trace ions in water supply, such as Na+, K+, Ca2+, Mg2+ and Cl-, SO(4)2-, CO(3)2- etc. 17O-NMR chemical shift and line-width of water were measured under different temperature and different concentrations of various salts in aqueous solutions containing those ions. The relationship of 17O-NMR chemical shift and line-width of water to water association and the effect of ions on water association were analyzed. Cations promoted water association and anions destroyed water association. Generally, the more the ionic charge and the larger the ionic radius, the larger was the effect of those ions on water association. Besides, the effect of ionic charge on water association was more significant than that of ionic radius.