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1.
Mol Cell ; 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-32017896

RESUMO

U6 snRNA, as an essential component of the catalytic core of the pre-mRNA processing spliceosome, is heavily modified post-transcriptionally, with 2'-O-methylation being most common. The role of these modifications in pre-mRNA splicing as well as their physiological function in mammals have remained largely unclear. Here we report that the La-related protein LARP7 functions as a critical cofactor for 2'-O-methylation of U6 in mouse male germ cells. Mechanistically, LARP7 promotes U6 loading onto box C/D snoRNP, facilitating U6 2'-O-methylation by box C/D snoRNP. Importantly, ablation of LARP7 in the male germline causes defective U6 2'-O-methylation, massive alterations in pre-mRNA splicing, and spermatogenic failure in mice, which can be rescued by ectopic expression of wild-type LARP7 but not an U6-loading-deficient mutant LARP7. Our data uncover a novel role of LARP7 in regulating U6 2'-O-methylation and demonstrate the functional requirement of such modification for splicing fidelity and spermatogenesis in mice.

2.
Bioresour Technol ; 297: 122480, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31812912

RESUMO

Microwave-assisted pyrolysis of waste suffers from the problem that the waste generally has low microwave absorptivity thereby resulting in low heating rate and low pyrolysis temperature. In this case, fast microwave-assisted pyrolysis is proposed and developed to help the pyrolysis of waste. This study describes two methods that can be used to realize fast microwave-assisted pyrolysis of waste: (1) premixed method (wastes are mixed with microwave absorbent) and (2) non-premixed method (wastes are poured onto the heated microwave absorbent bed). Then, biofuels (bio-oil, bio-gas, and bio-char) produced from fast microwave-assisted pyrolysis of wastes are reviewed. The review results show that the yields of bio-oil, bio-gas, and bio-char obtained from fast microwave-assisted pyrolysis of wastes varied significantly in the ranges of 2-96 wt%, 2.4-86.8 wt%, and 0.3-83.2 wt%, respectively. Although the present research focused mainly on the premixed method, non-premixed/continuous fast microwave-assisted pyrolysis is still promising and challenging.


Assuntos
Biocombustíveis , Micro-Ondas , Calefação , Temperatura Alta , Pirólise
3.
Eur J Clin Pharmacol ; 76(2): 139-147, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31748819

RESUMO

PURPOSE: The aim of this study was to explore the relationship between proton pump inhibitors use and the risk of dementia. METHODS: A comprehensive literature search was conducted in English and Chinese databases from origination to December 2018. The pooled hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated with a random-effects model. Subgroup analyses and sensitivity analyses were also conducted. Cochran's Q test and the I2 statistic were used to evaluate the heterogeneity. Publication bias was assessed by Begg's test and Egger's test. RESULTS: Six studies were included, which contained a total of 166,146 participants. The overall result demonstrated a significant increase in dementia risk with proton pump inhibitors use (HR = 1.29, 95% CI = 1.12-1.49). In subgroup analyses, a significant association was detected between proton pump inhibitors use and the risk of dementia in Europe (HR = 1.46, 95% CI = 1.23-1.73) and among participants aged ≥ 65 years (HR = 1.39, 95% CI = 1.17-1.65). For the factor follow-up time ≥ 5 years, the pooled HR was 1.28 (95% CI = 1.12-1.46), demonstrating a 1.28-fold increase in the risk of dementia among proton pump inhibitors users. In the case of regional impact, participants from Europe showed an overall pooled HR estimate of 1.46 (95% CI = 1.23-1.73). There was no evidence of publication bias. CONCLUSIONS: The overall result of this meta-analysis supports the hypothesis that proton pump inhibitors increase the risk of dementia. Furthermore, high-quality cohort studies are needed to confirm these findings.

4.
J Clin Periodontol ; 47(2): 134-147, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31697412

RESUMO

OBJECTIVE: To evaluate the association between periodontitis and the incidence and mortality of gastrointestinal cancer. METHOD: A comprehensive literature search was conducted to identify all relevant studies published prior to April 2019 according to the established inclusion criteria. The pooled hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated with a random-effects model. RESULTS: We identified 10 studies with 26 estimates of the relationship between periodontitis and gastrointestinal cancer. The HR for the incidence of gastrointestinal cancer in periodontitis was 1.23 (95% CI: 1.10-1.37). Subgroup analyses showed that periodontitis was associated with an increased risk of gastrointestinal cancers in prospective cohort studies and high-quality studies, North American individuals, and individuals 18 years or older, as well as when the dental status was self-reported and when the study was adjusted for smoking. A meta-analysis of nine reports demonstrated that periodontitis was associated with increased mortality from gastrointestinal cancer (HR = 1.59, 95% CI: 1.16-2.16). Additionally, periodontitis was associated with mortality from pancreatic cancer (HR = 2.20, 95% CI: 1.44-3.37); thus, periodontitis may be a risk factor for pancreatic cancer. CONCLUSION: Our meta-analysis demonstrated that periodontitis may be a risk factor for gastrointestinal cancers. Additional prospective cohort studies are warranted to confirm these findings.

5.
J Dig Dis ; 21(1): 38-45, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31714673

RESUMO

OBJECTIVES: The activation of the adenosine A3 receptor (A3AR) can regulate inflammation, but the way that this regulates colonic mucosal inflammation in ulcerative colitis (UC) remains unclear. This study aimed at examining A3AR expression and investigating the effect of A3AR activation on ex vivo cytokine expression and nuclear factor-kappa B (NF-κB) signaling in colonic mucosa. METHODS: Colonic mucosal biopsied tissue from 18 patients with UC and 11 healthy controls was tested for A3AR expression by immunofluorescence, quantitative real-time polymerase chain reaction and Western blot. Following treatment for 24 hours with or without 2-Cl-IB-MECA, an A3AR agonist, TNF-α and IL-1ß secreted by the cultured colonic mucosal tissue were quantified by ELISA. The colonic mucosal epithelia were dissected and treated with, or without 2-Cl-IB-MECA for 24 hours. The NF-κB p65 protein and its distribution in the cultured colonic epithelia were examined by immunofluorescence and Western blot. RESULTS: Compared with the controls, down-regulated A3AR expression and up-regulated TNF-α and IL-1ß production and NF-κB p65 protein were observed in the UC colonic mucosa. The activation of A3AR by 2-Cl-IB-MECA significantly decreased TNF-α and IL-1ß production and attenuated the NF-κB p65 activation in colonic tissues from patients with UC. CONCLUSIONS: A3AR activation inhibited inflammation by mitigating pro-inflammatory cytokine production and the NF-κB signal activation in colonic mucosa of patients with UC. A3AR activation may play a role in the pathogenesis of UC.

6.
J Sleep Res ; 29(1): e12876, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31352687

RESUMO

Recently, emerging studies on the relationship between insomnia, the most common sleep disorder, and cancer have been published, but with inconsistent results. With the development of society and the accelerated pace of life, more and more people experience insomnia. Therefore, it is important to clarify the association. Relevant literature was obtained through a search of seven databases and supplementary searches. After a strict screening, eight cohort studies (seven prospective and one retrospective) involving 578,809 participants and 7,451 cancer events were incorporated into our analysis. The results demonstrate a modest 24% overall increased risk of cancer for individuals with insomnia in comparison to those without insomnia. The sensitivity analysis shows that the correlation between the two is stable. Subgroup analyses show that the risk of developing cancer was significantly higher in studies conducted in women (HR = 1.24; 95% CI, 1.01-1.53), but not in men (HR = 1.28; 95% CI, 0.90-1.80). Similarly, in terms of specific cancer types, the pooled HR was only significantly higher in thyroid cancer (HR = 1.36; 95% CI, 1.12-1.65) and not in other types of cancer (p > 0.05). Our findings suggest that insomnia may serve as an early warning sign of the onset of cancer and provide an opportunity for early detection and early intervention. Our findings should be treated with caution because of the limited number of included studies and potential bias. More additional studies are warranted to provide more information on the carcinogenic effect of insomnia.

7.
Bioorg Chem ; 94: 103362, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31668463

RESUMO

A novel cyclopentenone derivative, talarocyclopenta A (1), a new phenolicethers derivative, talarocyclopenta B (2) and a new itaconic acid derivative, talarocyclopenta C (3) together with four known itaconic acid derivatives (4-7) were isolated from the Talaromyces assiutensis JTY2. Their structures were elucidated by the detailed analysis of comprehensive spectroscopic data. Among them, talarocyclopent (1) is the first represent an unusual type of cyclopentenone derivative, possessing a cyclopentenone unit, a 2-butanone unit and a 3-hydroxybutyric acid unit. All isolated compounds were evaluated for their anti-inflammatory and antibacterial activities. Compounds 1-4 showed inhibitory activities against the nitric oxide (NO) production induced by lipopolysaccharide in mouse macrophage RAW 264.7 cells in vitro. Compound 2 showed broad spectrum antibacterial against six terrestrial pathogenic bacteria.

8.
J Exp Med ; 217(1)2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31636135

RESUMO

Follicular helper T (Tfh) cells provide essential help for humoral immune response. Transcriptional factor Bcl6 is the master regulator for Tfh generation and is induced very early after T cell activation in a CD28-dependent manner, but how CD28 signal promotes Bcl6 early expression remains unknown. Here we found that CD28 signal quickly induces expression of the H3K36me2 methytransferase Nsd2, which is required for Bcl6 expression as early as the first cell division after T cell activation. Nsd2 deficiency in T cells leads to decreased Bcl6 expression, impaired Tfh generation, compromised germinal center response, and delayed virus clearance. Ectopic Bcl6 expression rescues the Tfh defect of Nsd2 KO cells. ICOS signal is dispensable for early Nsd2 induction but required for sustained Nsd2 expression, which is critical for Tfh maintenance. Overexpression of Nsd2 increases Bcl6 expression and enhances Tfh generation; 4-mo-old mice even develop spontaneous Tfh. Overall, our study reveals Nsd2 as a critical epigenetic regulator for Tfh differentiation.

9.
Environ Sci Technol ; 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31790213

RESUMO

Despite recent evidence from full-scale plants suggesting that Candidatus Accumulibacter may be capable of using amino acids, this metabolic trait has never been confirmed in a bioreactor experiment. Here we show that an enriched culture of Ca. Accumulibacter clade IIF strain SCELSE-1 could metabolize 11 of 20 α-amino acids, with aspartate, glutamate, asparagine, and glutamine resulting in the highest phosphorus removal. The anaerobic uptake of aspartate and glutamate was achieved through a glutamate/aspartate-proton symporter fully powered by the proton motive force (PMF). Under anaerobic conditions aspartate was deaminized and routed into core carbon metabolic pathways to form polyhydroxyalkanoates (PHA). The lack of genes encoding NADH dependent isocitrate dehydrogenase in the Ca. Accumulibacter genome resulted in a kinetic barrier for glutamate to be channelled to the TCA cycle. Glutamate was stored as glutamate polymer. When amino acids (aspartate or glutamate) and acetate were supplied together, Ca. Accumulibacter took up both carbon sources simultaneously, with the uptake rate of each carbon source largely preserved. Overall energy savings (up to 17%) were achieved under mixed carbon scenarios, due to the ability of Ca. Accumulibacter to rearrange its anaerobic carbon metabolism based on the reducing power, PMF and ATP balance.

10.
Cell ; 179(7): 1566-1581.e16, 2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31835033

RESUMO

Spermiogenesis is a highly orchestrated developmental process during which chromatin condensation decouples transcription from translation. Spermiogenic mRNAs are transcribed earlier and stored in a translationally inert state until needed for translation; however, it remains largely unclear how such repressed mRNAs become activated during spermiogenesis. We previously reported that the MIWI/piRNA machinery is responsible for mRNA elimination during late spermiogenesis in preparation for spermatozoa production. Here we unexpectedly discover that the same machinery is also responsible for activating translation of a subset of spermiogenic mRNAs to coordinate with morphological transformation into spermatozoa. Such action requires specific base-pairing interactions of piRNAs with target mRNAs in their 3' UTRs, which activates translation through coupling with cis-acting AU-rich elements to nucleate the formation of a MIWI/piRNA/eIF3f/HuR super-complex in a developmental stage-specific manner. These findings reveal a critical role of the piRNA system in translation activation, which we show is functionally required for spermatid development.

11.
Environ Health ; 18(1): 98, 2019 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-31771610

RESUMO

BACKGROUND: Very few studies have focused on the relationship between ambient apparent temperature (AT) and admission of mental and behaviour disorders (MDs). Therefore, a time-series study was conducted in Yancheng, China, to explore the effects of AT on the daily emergency admissions of patients with MDs over the period of 2014-17. METHODS: A quasi-Poisson generalized linear model (GLM) combined with a distributed lag non-linear model (DLNM) was adopted to explore the associations after adjusting for time trend, day of the week, humidity, sunshine duration, rainfall, holidays and air pollutants. In the subgroup analysis, the modification effects of age and sex were also examined. RESULTS: Overall, 8438 cases of MDs emergency admissions were identified. With the apparent temperature with the minimum number of admissions (- 3.4 °C) serving as a reference, a positive correlation emerged between high AT and daily emergency admissions of patients with MDs in Yancheng, China, with the lagged effect of 1 to 5 days. The subgroup analysis demonstrated a positive relationship between AT and MDs emergency admissions among males and individuals younger than 45 years old, with no lagged effect. CONCLUSIONS: The results will provide important scientific evidence for mental health policy-makers and practitioners for possible intervention, especially among the vulnerable populations.

12.
Fitoterapia ; 139: 104400, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31669962

RESUMO

Two novel epimer pairs of acetaminophen derivatives penicilquei A-D (1-4) were isolated from Penicillium herquei JX4. Their structures were elucidated using comprehensive spectroscopic methods. The absolute configurations of penicilquei A-D (1-4) were determined by modifified Mosher's method, and comparing their experimental and calculated electronic circular dichroism (ECD) spectra. Penicilquei A-D (1-4) are the first example of acetaminophen derivatives featuring an unprecedented carbon skeleton. The inhibitory activities of all compounds against nine phytopathogenic fungi and α-glucosidase were evaluated. Penicilquei A-D (1-4) showed strong inhibitory activities against at least eight phytopathogenic fungus.


Assuntos
Acetaminofen/farmacologia , Fungicidas Industriais/farmacologia , Penicillium/química , Acetaminofen/química , China , Fungicidas Industriais/química , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Estrutura Molecular , Rhizophoraceae/microbiologia
13.
Blood Press ; : 1-10, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31718311

RESUMO

Purposes: Many studies have indicated that orthostatic hypotension (OH) may be a risk factor for dementia and stroke, but the results have been inconsistent. To further ascertain the links between OH and cognition or stroke, a meta-analysis was performed.Methods: The Chinese Biomedical Database, PubMed, Web of Science, and the Cochrane Library database were searched (up to March 2019) to identify prospective cohort studies that examined the associations between OH and the risks of stroke and dementia among adult populations. Subgroup analyses and meta-regression analyses were conducted to identify sources of heterogeneity. We also performed Begg's test and Egger's test to assess publication bias.Results: A total of 3490 articles were identified, and 18 prospective observational cohort studies were ultimately included. Among these studies, eight prospective studies were about stroke, nine studies were about cognition and one study reported data about both stroke and dementia. Meta-analysis revealed an association between OH and worse cognition (hazard ratio (HR): 1.18, 95% confidence interval (CI): 1.03-1.35, I2 = 69.5%). For dementia, the pooled HR was 1.30, with 95% CI: 1.14-1.48, I2 = 31.0%. In addition, we found that OH was associated with a higher risk of stroke (HR: 1.36, 95% CI = 1.17-1.57, I2 = 67.3%). No publication bias was detected.Conclusion: This meta-analysis provides evidence that OH was associated with worse cognition. OH accounted for a 30% increase in the risk of dementia and a 36% increase in the risk of stroke.

14.
J Microbiol Methods ; 167: 105778, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31733264

RESUMO

This study demonstrates an effective technique for separating and purifying viable bacteria from samples that interfere with viability staining. The viability of Bifidobacterium longum ATCC 15707 was assessed using Percoll Buoyant Density Gradient Centrifugation (PBDC) to separate bacteria from complex non-dairy food matrices and Quantitative Fluorescence Microscopy (QFM) to determine individual cells using LIVE/DEAD BacLight bacterial viability staining. Water agar (3%) was used to retain cells of B. longum and offered a lower fluorescence background with BacLight viability staining, compared with fixation on polycarbonate (PC) black membrane. The effect of drying temperatures and non-dairy foods on viability of B. longum was assessed. B. longum coated on oat, peanut or raisin was separated by filtration, low- and high-speed centrifugation, flotation and sedimentation buoyant density centrifugation. Purified cells were subsequently deposited on water agar for rehydration followed by LIVE/DEAD BacLight viability staining and enumeration. Conventional plate counting was also conducted to compare viability results. Finally, this method was applied to assess cell membrane damages of B. longum incorporated onto non-dairy foods during 24 h drying. Furthermore, viability assessment of B. longum coated onto oat, peanut, or raisin was much lower by plate counting compared to viability staining. Drying appeared to have a greater impact when viability was assessed by plate counting compared to viability staining. IMPORTANCE: Enumeration of viable beneficial bacteria from function foods presents a significant bottleneck for product development and quality control. Interference with microscopic and/or fluorescent techniques by ingredients, time required to incubate plated microbes, and the transient nature of the colony forming unit make rapid assessment of viable bacteria difficult. Viability assessment of Bifidobacterium longum ATCC 15707 by Percoll Buoyant Density Gradient Centrifugation with LIVE/DEAD BacLight viability staining on water agar (3%) was in agreement with serial dilution enumeration. Without the need for incubation viability assessment by staining provided a more rapid means to assess the impact of drying on the viability of B. longum coated onto oat, peanut or raisin.

15.
JAMA Netw Open ; 2(10): e1913619, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31626318

RESUMO

Importance: The role of induction chemotherapy (IC) or adjuvant chemotherapy (AC) in the treatment of locoregionally advanced nasopharyngeal carcinoma (NPC) remains controversial. Objectives: To update meta-analyses on the association of survival outcomes with IC and AC regimens in patients with locoregionally advanced NPC and assess whether the current evidence is conclusive by a trial sequential analysis (TSA) approach. Data Sources: PubMed, Embase, and Web of Science were searched for articles published from inception until June 1, 2019. Study Selection: Randomized clinical trials that assessed the efficacy of radiotherapy with or without chemotherapy among previously untreated patients and patients with nondistant metastatic NPC. Data Extraction and Synthesis: Data were extracted by 2 investigators from each trial independently and synthesized by the 2 investigators. All trial results were combined and analyzed by a fixed- or random-effects model. Main Outcomes and Measures: Overall survival (OS), progression-free survival (PFS), distant metastasis-free survival (DMFS), and locoregional recurrence-free survival (LRFS). Results: A total of 8036 patients (median age, 46.5 years; 5872 [73.1%] male) from 28 randomized clinical trials were included in the analysis. Pooled analyses revealed that concurrent chemoradiotherapy (CCRT) was significantly associated with improved OS, PFS, DMFS, and LRFS compared with radiotherapy across all subgroups. The TSA confirmed the treatment outcomes of CCRT compared with radiotherapy. The additional IC regimen was associated with an improvement in OS (hazard ratio [HR], 0.84; 95% CI, 0.74-0.95), PFS (HR, 0.73; 95% CI, 0.64-0.84), DMFS (HR, 0.67; 95% CI, 0.59-0.78), and LRFS (HR, 0.74; 95% CI, 0.64-0.85). These findings were consistent in subgroup analyses of multicenter trials with sample sizes greater than 250, years of survival rate of 5 or greater, median follow-up longer than 5 years, or low risk of bias. However, the additional AC regimen was not associated with a survival benefit in OS (HR, 0.98; 95% CI, 0.78-1.23), PFS (HR, 0.86; 95% CI, 0.70-1.07), DMFS (HR, 0.84; 95% CI, 0.64-1.10), or LRFS (HR, 0.80, 95% CI, 0.59-1.09). The TSA provided sound evidence on the additional benefit of IC but not AC. Conclusions and Relevance: These data suggest a significant association of survival outcomes with CCRT in patients with locoregionally advanced NPC. The addition of IC instead of AC could achieve survival benefits. The potential therapeutic gain of AC should be explored in the future.

16.
Proc Natl Acad Sci U S A ; 116(46): 23264-23273, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31662475

RESUMO

Glycolytic enzyme phosphoglycerate mutase 1 (PGAM1) plays a critical role in cancer metabolism by coordinating glycolysis and biosynthesis. A well-validated PGAM1 inhibitor, however, has not been reported for treating pancreatic ductal adenocarcinoma (PDAC), which is one of the deadliest malignancies worldwide. By uncovering the elevated PGAM1 expressions were statistically related to worse prognosis of PDAC in a cohort of 50 patients, we developed a series of allosteric PGAM1 inhibitors by structure-guided optimization. The compound KH3 significantly suppressed proliferation of various PDAC cells by down-regulating the levels of glycolysis and mitochondrial respiration in correlation with PGAM1 expression. Similar to PGAM1 depletion, KH3 dramatically hampered the canonic pathways highly involved in cancer metabolism and development. Additionally, we observed the shared expression profiles of several signature pathways at 12 h after treatment in multiple PDAC primary cells of which the matched patient-derived xenograft (PDX) models responded similarly to KH3 in the 2 wk treatment. The better responses to KH3 in PDXs were associated with higher expression of PGAM1 and longer/stronger suppressions of cancer metabolic pathways. Taken together, our findings demonstrate a strategy of targeting cancer metabolism by PGAM1 inhibition in PDAC. Also, this work provided "proof of concept" for the potential application of metabolic treatment in clinical practice.

17.
Angew Chem Int Ed Engl ; 58(48): 17194-17198, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31538687

RESUMO

Excellent nonlinear optical materials simultaneously meet the requirements of large SHG response, phase-matching capability, wide transparency windows, considerable energy band-gap, good thermal stability and structure stability. Herein, two new promising nonlinear optical (NLO) crystals LiMII (IO3 )3 (MII =Zn and Cd) are rationally designed by the aliovalent substitution strategy from the commercialized α-LiIO3 with the perfect parallel alignment of IO3 groups. Compared with parent α-LiIO3 and related AI 2 MIV (IO3 )6 , the title compounds exhibit more stable covalent 3D structure, and overcome the racemic twinning problem of AI 2 MIV (IO3 )6 . More importantly, both compounds inherit NLO-favorable structure merits of α-LiIO3 and show larger SHG response (≈14× and ≈12×KDP), shorter absorption edge (294 and 297 nm) with wider energy band-gap (4.21 and 4.18 eV), good thermal stability (460 and 430 °C), phase-matching behaviors, wider optical transparency window and good structure stability, achieving an excellent balance of NLO properties.

18.
Alzheimers Dement (N Y) ; 5: 441-449, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31517031

RESUMO

Introduction: This randomized, double-blind trial aimed to test effect of a Chinese herbal medicine, Qinggongshoutao (QGST) pill, on the cognition and progression of amnestic mild cognitive impairment (aMCI). Methods: Patients with aMCI were randomly assigned to receive QGST, Ginkgo biloba extract, or placebo for 52 weeks. The primary outcome measures were progression to possible or probable Alzheimer's disease (AD) and change in Alzheimer's Disease Assessment Scale-cognitive subscale scores; secondary outcome measures included assessments for cognition and function. Results: Total 350 patients were enrolled, possible or probable AD developed in 10. There were significant differences in the probability of progression to AD in the QGST group (1.15%) compared with placebo group (10%). There was significant difference in Alzheimer's Disease Assessment Scale-cognitive subscale scores in favor of QGST over the placebo group. Secondary outcome measure (Mini-Mental State Examination) also showed benefit in QGST at end point. Discussion: In patients with aMCI, QGST showed lower AD progression rate than placebo at 8.85%, and may have benefit on global cognition.

19.
Ying Yong Sheng Tai Xue Bao ; 30(9): 3183-3194, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31529894

RESUMO

Soil organic carbon is essential for maintaining terrestrial ecosystem function and mitigating soil degradation. Soil microorganisms participate in soil carbon cycling. They are affected by tillage methods and straw returning. A split-plot design was adopted in this experiment. The whole-plot treatment had two tillage methods, subsoil tillage (ST) and rotary tillage (RT). The split-plot treatment included full straw returning (F) and no straw returning (0). The microbial community structure and carbon sequestration genes were assessed by Illumina sequencing technique. Soil organic carbon contents were measured during 2012-2017. The results showed that 1) subsoil tillage and straw returning significantly increased pH, microbial biomass carbon, total nitrogen, silt content, and clay content, while significantly decreased sand content; 2) during the test period (2012-2017), soil organic carbon (SOC) content under all treatments showed an increasing trend, but the increment for average SOC content under straw returning and subsoiling treatments was significantly higher than that of no straw returning and rotary tillage by 33.2 % and 30.6%, respectively; 3) Proteobacteria was the most abundant type of bacteria in the soil, followed by Acidobacteria and Gemmatadanetes; 4) STF treatment maintained high microbial diversity; 5) Excepted for soil sand content, soil pH, microbial biomass carbon, total nitrogen, silt content and clay content all caused the variation of soil microbial community structure under the STF treatment in the direction of SOC accumulation; 6) in addition to the gene abundance in the di- and oligosaccharides metabolic pathway, the gene abundance in the metabolic pathways for CO2 fixation, central carbohydrate metabolism, fermentation, one-carbon metabolism, organic acids, sugar alcohols and glycoside hydrolases showed that subsoil tillage was significantly higher than rotary tillage, with posi-tively correlation with soil organic carbon content. Therefore, the combination of subsoil tillage and straw returning could improve basic soil properties, affect soil microbial community structure, and increase the capacity of soil carbon fixation, thus providing a realistic basis for solving soil degradation.


Assuntos
Agricultura , Microbiota , Microbiologia do Solo , Solo , Carbono/análise , Triticum
20.
Dalton Trans ; 48(35): 13423-13429, 2019 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-31433416

RESUMO

Silver doped TiO2 (Ag-TiO2) materials show high activity and good stability in photocatalysis, but the mechanism could not be illustrated clearly due to their imprecise and inhomogeneous characteristics. Ag-doped titanium-oxo clusters (Ag-TOCs) with an exact crystal structure, which are rarely reported, are beneficial for further understanding structure-property relationships. Herein, six new Ag-TOCs with a butterfly-like Ti8Ag2 core have been synthesized through facile solvothermal reactions, in which two Ag ions are successfully linked to the surface of the Ti8 core. Of interest, the Ti6 unit of the Ti8Ag2 core is similar to that found in the anatase structure and may be a promising model for Ag-TiO2 materials. The band gaps of these Ag-TOCs show different values mainly affected by different ligands. DFT calculations revealed that the lowest energy bands of Ag-TOCs are attributed to the Ag-to-TiO core charge transfer bands. Additionally, all Ag-TOCs exhibit good photoelectric response and high photodegradation activity towards organic dyes.

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