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1.
Sensors (Basel) ; 19(18)2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31487866

RESUMO

When faced with problems such as traffic state estimation, state prediction, and congestion identification for the expressway network, a novel switched observer design strategy with jump states is required to reconstruct the traffic scene more realistically. In this study, the expressway network is firstly modeled as the special discrete switched system, which is called the piecewise affine system model, a partition of state subspace is introduced, and the convex polytopes are utilized to describe the combination modes of cells. Secondly, based on the hybrid dynamic traffic network model, the corresponding switched observer (including state jumps) is designed. Furthermore, by applying multiple Lyapunov functions and S-procedure theory, the observer design problem can be converted into the existence issue of the solutions to the linear matrix inequality. As a result, a set of gain matrices can be obtained. The estimated states start to jump when the mode changes occur, and the updated value of the estimated state mainly depends on the estimated and the measured values at the previous time. Lastly, the designed state jump observer is applied to the Beijing Jingkai expressway, and the superiority and the feasibility are demonstrated in the application results.

2.
Biomed Environ Sci ; 32(8): 578-591, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31488234

RESUMO

OBJECTIVE: We aimed to explore how fermented barley extracts with Lactobacillus plantarum dy-1 (LFBE) affected the browning in adipocytes and obese rats. METHODS: In vitro, 3T3-L1 cells were induced by LFBE, raw barley extraction (RBE) and polyphenol compounds (PC) from LFBE to evaluate the adipocyte differentiation. In vivo, obese SD rats induced by high fat diet (HFD) were randomly divided into three groups treated with oral gavage: (a) normal control diet with distilled water, (b) HFD with distilled water, (c) HFD with 800 mg LFBE/kg body weight (bw). RESULTS: In vitro, LFBE and the PC in the extraction significantly inhibited adipogenesis and potentiated browning of 3T3-L1 preadipocytes, rather than RBE. In vivo, we observed remarkable decreases in the body weight, serum lipid levels, white adipose tissue (WAT) weights and cell sizes of brown adipose tissues (BAT) in the LFBE group after 10 weeks. LFBE group could gain more mass of interscapular BAT (IBAT) and promote the dehydrogenase activity in the mitochondria. And LFBE may potentiate process of the IBAT thermogenesis and epididymis adipose tissue (EAT) browning via activating the uncoupling protein 1 (UCP1)-dependent mechanism to suppress the obesity. CONCLUSION: These results demonstrated that LFBE decreased obesity partly by increasing the BAT mass and the energy expenditure by activating BAT thermogenesis and WAT browning in a UCP1-dependent mechanism.

3.
Nat Commun ; 10(1): 4145, 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31515482

RESUMO

Crystallographic dislocation has been well-known to be one of the major causes responsible for the unfavorable carrier dynamics in conventional semiconductor devices. Halide perovskite has exhibited promising applications in optoelectronic devices. However, how dislocation impacts its carrier dynamics in the 'defects-tolerant' halide perovskite is largely unknown. Here, via a remote epitaxy approach using polar substrates coated with graphene, we synthesize epitaxial halide perovskite with controlled dislocation density. First-principle calculations and molecular-dynamics simulations reveal weak film-substrate interaction and low density dislocation mechanism in remote epitaxy, respectively. High-resolution transmission electron microscopy, high-resolution atomic force microscopy and Cs-corrected scanning transmission electron microscopy unveil the lattice/atomic and dislocation structure of the remote epitaxial film. The controlling of dislocation density enables the unveiling of the dislocation-carrier dynamic relation in halide perovskite. The study provides an avenue to develop free-standing halide perovskite film with low dislocation density and improved carried dynamics.

4.
BMJ Open ; 9(8): e026677, 2019 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-31446403

RESUMO

OBJECTIVES: Despite the publication of hundreds of trials on gout and hyperuricemia, management of these conditions remains suboptimal. We aimed to assess the quality and consistency of guidance documents for gout and hyperuricemia. DESIGN: Systematic review and quality assessment using the appraisal of guidelines for research and evaluation (AGREE) II methodology. DATA SOURCES: PubMed and EMBASE (27 October 2016), two Chinese academic databases, eight guideline databases, and Google and Google scholar (July 2017). ELIGIBILITY CRITERIA: We included the latest version of international and national/regional clinical practice guidelines and consensus statements for diagnosis and/or treatment of hyperuricemia and gout, published in English or Chinese. DATA EXTRACTION AND SYNTHESIS: Two reviewers independently screened searched items and extracted data. Four reviewers independently scored documents using AGREE II. Recommendations from all documents were tabulated and visualised in a coloured grid. RESULTS: Twenty-four guidance documents (16 clinical practice guidelines and 8 consensus statements) published between 2003 and 2017 were included. Included documents performed well in the domains of scope and purpose (median 85.4%, range 66.7%-100.0%) and clarity of presentation (median 79.2%, range 48.6%-98.6%), but unsatisfactory in applicability (median 10.9%, range 0.0%-66.7%) and editorial independence (median 28.1%, range 0.0%-83.3%). The 2017 British Society of Rheumatology guideline received the highest scores. Recommendations were concordant on the target serum uric acid level for long-term control, on some indications for urate-lowering therapy (ULT), and on the first-line drugs for ULT and for acute attack. Substantially inconsistent recommendations were provided for many items, especially for the timing of initiation of ULT and for treatment for asymptomatic hyperuricemia. CONCLUSIONS: Methodological quality needs improvement in guidance documents on gout and hyperuricemia. Evidence for certain clinical questions is lacking, despite numerous trials in this field. Promoting standard guidance development methods and synthesising high-quality clinical evidence are potential approaches to reduce recommendation inconsistencies. PROSPERO REGISTRATION NUMBER: CRD42016046104.

5.
Ann Thorac Surg ; 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31400325

RESUMO

BACKGROUND: Systematic inflammation-immune status has been thought to play a crucial role in tumorigenesis and progress. This study evaluated the prognostic value of systematic inflammation-immune status in patients with resected non-small cell lung cancer with pathological N2 nodal involvement (pN2-NSCLC). METHODS: The relation between preoperative systematic inflammation-immune score (SIS, defined as preoperative peripheral platelet count ×neutrophil count / lymphocyte count) and prognosis was tested in a retrospective study of 660 consecutive patients with completed resected pN2-NSCLC and validated by a prospective study of 189 patients enrolled (NCT00880971). RESULTS: SIS of 650×109 was found to be an optimal cutoff point to stratify the patients with pN2-NSCLC into high (>650×109) and low (≤650×109) SIS groups in the training cohort. Univariate and multivariate analyses revealed that the SIS was an independent predictor for overall survival, disease-free survival and distant metastasis-free survival. In the validation group, high SIS (>650×109) was shown to predict poor 5-year overall survival (p=0.006, hazard ratio [HR]=2.418), disease-free survival (p=0.042, HR=1.542) and distant metastasis-free survival (p=0.024, HR=1.682). In addition to the number of positive lymph nodes, the area under the receiver operating characteristic curve of the SIS for outcomes was higher than neutrophil count / lymphocyte count ratio, platelet count / lymphocyte count ratio and other conventional clinicopathologic indices. CONCLUSIONS: The preoperative SIS is a more sensitive survival predictor than most of other conventional clinical indices and may aid in more accurately stratifying patients for risk assessment and treatment decision.

6.
BMC Pregnancy Childbirth ; 19(1): 302, 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31426762

RESUMO

BACKGROUND: To assess whether the peri-conceptional or pregnancy exposure of human papillomavirus (HPV) vaccination would increase the risk of spontaneous abortion. METHODS: We searched PubMed, Embase, and Cochrane Central Register of Controlled Trials for clinical trials and observational studies that investigated the association between exposure of HPV vaccines (2vHPV, 4vHPV or 9vHPV) during peri-conceptional period or pregnancy and spontaneous abortion before 28 gestational weeks. We pooled data from 2vHPV, 4vHPV and 9vHPV separately. Subgroup analyses were conducted according to data sources, and raw data or adjusted data. RESULTS: Seven observational studies were eligible and all studies were low risk of bias. Meta-analyses suggested that 2vHPV vaccination did not increase the risk of spontaneous abortion regardless of exposure period during 90 days before last menstrual period (LMP) or pregnancy: risk ratio, 95% confidence intervals (RR, 95% CI), 1.15 (0.95-1.39), and 45 days before LMP or pregnancy: 1.28 (0.96-1.70). However, 2vHPV vaccination during Pre-45 days to LMP seemed to increase the risk of spontaneous abortion: 1.59 (1.04-2.45). The current evidence did not support the association between 4vHPV vaccination and spontaneous abortion regardless of exposure period during 45 days before LMP or pregnancy: 0.88 (0.73-1.06); and 45 days before LMP: 1.00 (0.80-1.24). Additionally, 9vHPV during within 30 days of conception also seemed to increase the risk: 2.04 (1.28-3.24). CONCLUSIONS: The association between peri-conceptional or pregnancy exposure of HPV vaccine and spontaneous abortion is still uncertain, and additional research is warranted to assess the impact of exposure of HPV vaccination on spontaneous abortion.

7.
Sci China Life Sci ; 2019 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-31463736

RESUMO

Crouzon syndrome is the result of a gain-of-function point mutation in FGFR2. Mimicking the human mutation, a mouse model of Crouzon syndrome (Fgfr2342Y) recapitulates patient deformities, including failed tracheal cartilage segmentation, resulting in a cartilaginous sleeve in the homozygous mutants. We found that the Fgfr2C342Y/C342Y mutants exhibited an increase in chondrocytes prior to segmentation. This increase is due at least in part to over proliferation. Genetic ablation of chondrocytes in the mutant led to restoration of segmentation in the lateral but not central portion of the trachea. These results suggest that in the Fgfr2C342Y/C342Y mutants, increased cartilage cell proliferation precedes and contributes to the disruption of cartilage segmentation in the developing trachea.

8.
Cancer Med ; 2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31436046

RESUMO

Although targeting DNA repair signaling pathways has emerged as a promising therapeutic for skin cancer, the relevance of DNA damage responses (DDR) in the development and survival of nonmelanoma skin cancer (NMSC), the most common type of skin cancer, remains obscure. Here, we report that Src-associated substrate during mitosis of 68 kDa (Sam68), an early signaling molecule in DDR, is elevated in skin tumor tissues derived from NMSC patients and skin lesions from Gli2-transgenic mice. Downregulation of Sam68 impacts the growth and survival of human tumor keratinocytes and genetic ablation of Sam68 delays the onset of basal cell carcinomas (BCC) in Gli2-transgenic mice. Moreover, Sam68 plays a critical role in DNA damage-induced DNA repair and nuclear factor kappa B (NF-κB) signaling pathways in keratinocytes, hence conferring keratinocyte sensitivity to DNA damaging agents. Together, our data reveal a novel function of Sam68 in regulating DDR in keratinocytes that is crucial for the growth and survival of NMSC.

9.
FEBS Lett ; 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31432514

RESUMO

The activation of Toll-like receptors (TLRs) leads to proinflammatory cytokine production, which is responsible for activating the innate immune system. Thus, TLR signaling is subject to multilayer regulatory control mechanisms that aim to prevent a protective response from causing injury. In the present study, we report that the E3 ubiquitin ligase RNF182 is highly expressed in macrophages and is specifically upregulated by TLR stimuli (TLR4, TLR3 and TLR9 agonists). Knockdown of RNF182 selectively amplifies TLR signaling by promoting the production of proinflammatory cytokines but not type I interferons in macrophages. Mechanistically, RNF182 promotes the degradation of p65 via K48-linked ubiquitination, resulting in the inhibition of TLR-triggered innate immune responses. Our findings highlight a feedback-negative mechanism for terminating TLR-induced inflammation and maintaining the immunological balance.

10.
J BUON ; 24(3): 997-1002, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31424653

RESUMO

PURPOSE: Cervical cancer causes considerable mortality in women world over and the current treatment options create severe adverse effects. Hence, there is an urgent need to develop novel and efficient treatment regimens for cervical cancer. Herein, we examined the anticancer effects of a natural coumarin, Scopoletin, against a panel of cervical cancer cell lines. METHODS: The antiproliferative effect of Scopoletin was examined by cell counting and colony formation assays. Apoptosis was detected by acridine orange (AO) ethidium promide (EB) staining. Cell cycle distribution was determined by flow cytometry. Cell invasion was examined by Boyden chamber assay. Protein expression was checked by western blotting. RESULTS: Scopoletin inhibited the growth of all the cell lines and the IC50 ranged between 7.5 to 25 µM. Nonetheless, the cytotoxic effects of Scopoletin were comparatively negligible against the normal cells with an IC50 of 90 µM. Investigation of the mechanism of action, revealed that the anticancer effects of Scopoletin against the HeLa cervical cancer cells were due to induction of apoptotic cell death as indicated AO/EB staining. Scopoletin treatment also resulted in enhancement of the Bax, Caspase 3, 8 and 9 expression and decline of the Bcl-2 expression. Scopoletin also blocked the HeLa cells at G2/M checkpoint of the cell cycle. Furthermore, cell invasion assay revealed that Scopoletin inhibited the migration of the HeLa cells concentration-dependently. PI3K/AKT is an imperative pathway involved in theproliferation and tumorigenesis of cancer cells and herein it was found that Scopoletin could inhibit this pathway. CONCLUSION: Taken together, Scopoletin may prove essential in the development of novel treatment regimes for cervical cancer.

11.
Plant Mol Biol ; 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31392474

RESUMO

KEY MESSAGE: Pre-treatment of soybean seedlings with 200 µM salicylic acid before fungal inoculation significantly alleviated disease resistance in soybean seedlings against Fusarium solani infection. Sudden death syndrome of soybean is largely caused by Fusarium solani (F. solani). Salicylic acid (SA) has been reported to induce resistance in plants against many pathogens. However, the effect of exogenous SA application on F. solani infection of soybean is less reported. This study investigated the effect of foliar application of SA on soybean seedlings before F. solani infection. Seedlings were sprayed with 200 µM SA and inoculated with F. solani after 24 h of last SA application. After 3 days post-inoculation, seedlings treated with 200 µM SA showed significantly fewer disease symptoms with increased endogenous SA level, SA marker genes expression and antioxidant activities in the SA-treated seedlings more than the untreated control seedlings. Furthermore, the decrease in hydrogen peroxide (H2O2) and malondialdehyde (MDA) levels was observed in the SA-treated plants as compared to the untreated plants. Analysis of the effect of SA application on F. solani showed that the mycelia growth of F. solani was not affected by SA treatment. Further investigation in this study revealed a decreased in F. solani biomass content in the SA treated seedlings. Results from the present study show that pre-treatment of 200 µM SA can induce resistance of soybean seedlings against F. solani infection.

12.
Sci Total Environ ; 689: 322-331, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31277000

RESUMO

Marine biofouling by the swiftly spreading invasive mussel (Musculista senhousia) has caused serious ecological and economic consequences in the global coastal waters. However, the fate of this highly invasive fouling species in a rapidly acidifying ocean remains unknown. Here, we demonstrated the impacts of ocean acidification within and across generations, to understand whether M. senhousia has the capacity to acclimate to changing ocean conditions. During the gonadal development, exposure of mussels to elevated pCO2 caused significant decreases of survival, growth performance and condition index, and shifted the whole-organism energy budget by inflating energy expenses to fuel compensatory processes, eventually impairing the success of spawning. Yet, rapid transgenerational acclimation occurred during the early life history stage and persisted into adulthood. Eggs spawned from CO2-exposed mussels were significantly bigger compared with those from non-CO2-exposed mussels, indicating increased maternal provisioning into eggs and hence conferring larvae resilience under harsh conditions. Larvae with a prior history of transgenerational exposure to elevated pCO2 developed faster and had a higher survival than those with no prior history of CO2 exposure. Transgenerational exposure significantly increased the number of larvae completing metamorphosis. While significant differences in shell growth were no longer observed during juvenile nursery and adult grow-out, transgenerationally exposed mussels displayed improved survival in comparison to non-transgenerationally exposed mussels. Metabolic plasticity arose following transgenerational acclimation, generating more energy available for fitness-related functions. Overall, the present study demonstrates the remarkable ability of M. senhousia to respond plastically and acclimate rapidly to changing ocean conditions.

13.
Environ Pollut ; 253: 680-707, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31330359

RESUMO

Solid wastes containing potentially toxic elements (PTEs) are widely generated around the globe. Critical concerns have been raised over their impacts on human health and the environment, especially for the exposure to PTEs during the transfer and disposal of the wastes. It is important to devise highly-efficient and cost-effective treatment technologies for the removal or immobilisation of PTEs in solid wastes. However, there is an inadequate overview of the global flow of PTEs-contaminated solid wastes in terms of geographical distribution patterns, which is vital information for decision making in sustainable waste management. Moreover, in view of the scarcity of resources and the call for a circular economy, there is a pressing need to recover materials (e.g., precious metals and rare earth elements) from waste streams and this is a more sustainable and environmentally friendly practice compared with ore mining. Therefore, this article aims to give a thorough overview to the global flow of PTEs and the recovery of waste materials. This review first summarises PTEs content in various types of solid wastes; then, toxic metal(loid)s, radioactive elements, and rare earth elements are critically reviewed, with respect to their patterns of transport transformation and risks in the changing environment. Different treatments for the management of these contaminated solid wastes are discussed. Based on an improved understanding of the dynamics of metal(loid) fates and a review of existing management options, new scientific insights are provided for future research in the development of high-performance and sustainable treatment technologies for PTEs in solid wastes.

14.
Zhongguo Zhong Yao Za Zhi ; 44(9): 1857-1861, 2019 May.
Artigo em Chinês | MEDLINE | ID: mdl-31342713

RESUMO

The change of icariin( ICA) content in thirty-three samples of five Epimedium species listed in the Chinese Pharmacopoeia( 2015 edition),including E. brevicornu,E. sagittatum,E. pubescens,E. koreanum,and E. wushanense has been investigated in this study. The results indicated that the optimized process procedure was baking at 150 ℃ for 30 min,and 3'''-carbonyl-2″-ß-L-quinovosyl icariin( CQICA) could not be translated into ICA and ICA could be converted under this heating process condition. ICA increased remarkably after the heating process by 1-3 times in E. brevicornu,E. wushanense and E. koreanum,and increased lightly in E. brevicornum and E. pubescens,while ICA slightly increased or decreased in E. sagittatum and E. wushanense.


Assuntos
Medicamentos de Ervas Chinesas/química , Epimedium/química , Flavonoides/análise , Temperatura Alta , Compostos Fitoquímicos/análise , Manejo de Espécimes
15.
J Clin Epidemiol ; 115: 98-105, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31326543

RESUMO

OBJECTIVE: The objective of the study was to examine methodological characteristics about the design and conduct in prognostic prediction models used for obstetric care. STUDY DESIGN AND SETTING: We searched PubMed for studies on prognostic prediction models for obstetric care, published in top general medicine or major specialty journals between January 2011 and February 2018. Teams of method-trained investigators independently screened titles and abstracts and collected data using a prespecified, pilot-tested, structured questionnaire. RESULTS: In total, 91 studies were eligible, of which two were published in top general medicine journals, 20 (22.0%) involved an epidemiologist or statistician, 18 (19.4%) published study protocols, 53 (58.2%) did not include any model validation, 20 (22.0%) did not clearly state the intended timing of use, 23 (25.3%) had no eligibility criteria, 15 (16.5%) did not use clear criteria for ascertaining outcome, and 69 (75.82%) did not apply blinding to outcome assessment. Among those models, 11 (12.1%) included participants fewer than 200 events, 41 (48.8%) had fewer than 100 events, and 19 (24.7%) had fewer than 10 events per variable. CONCLUSION: The prognostic prediction models have important limitations in design and conduct. Substantial efforts are needed to strengthen the production of reliable prognostic prediction models for obstetric care.

16.
Life Sci ; 232: 116630, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31279783

RESUMO

AIMS: Lung adenocarcinoma consists of multiple therapeutic targets, however, patients will inevitably progress to later stage diagnosis with Tyrosine Kinase Inhibitor treatment resistance. We aim to investigate the roles of non-coding TUSC7 in ordering the cell division tendency, helping to sensitize the resistance in a miRNA incorporating way. MATERIALS AND METHODS: Online study of bioinformatics analysis, molecular experiments of luciferase test, immunofluorescence staining and qRT-PCR were applied to dig out the mechanistic regulations. KEY FINDINGS: TUSC-7 inhibited the renewal ability of adenocarcinoma stem cells, yielding to asymmetric cell splitting. Informatics analysis and the luciferase testing confirmed the 3'UTR binding site, and revealed the post-transcriptional regulation of NUMB referring to miR-146. TUSC-7 sponged miR-146 and abolished its degradation toward to NUMB, and this integrated cascade made several genes become tangled to full functionality. SIGNIFICANCE: TUSC-7 was proved to be one strong suppressive lnc-RNA in lung adenocarcinoma stem cells, functioning through inactivating NOTCH signaling, and the turbulence on division modes precisely pointed to the key mechanisms of stem cells' renewal. The decreasing of tumor suppressive miR-146 was necessary in TUSC-7 conducted renewal repression, despite it alone could also reduce the renewal efficiency, indicating that more complicated non-coding genes may be involved in its regulation.

17.
Medicine (Baltimore) ; 98(29): e16561, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31335741

RESUMO

BACKGROUND: Peptic ulcer disease (PUD) is a major burden worldwide. Several challenges remain with standard Western treatment of PUD, such as persistent weakness, fatigue, and relapse. A dietary traditional Chinese medicine (TCM) formula, Hou Gu Mi Xi (HGMX), has been developed as a complementary treatment for PUD. AIMS: This multicenter, double-blind, randomized controlled trial will assess efficacy and safety of HGMX in patients with PUD. METHODS: Three hundred sixty eligible patients will be assigned to receive HGMX, placebo, HGMX + rabeprazole or placebo + rabeprazole for 4 weeks after 2 weeks of standard Western treatment. This first step, with a 2 × 2 factorial design, will focus on assessing the main and interaction effects of HGMX and rabeprazole on ulcer healing. Then, rabeprazole will be stopped, and HGMX will be continued for up to 1 year. The second step, with a placebo-controlled design, will compare the long-term effects of HGMX and placebo. Extended follow-up with no treatment will continue for up to 2 years. Independent and paired t tests, Pearson χ test and the rank-sum test will be used to compare between-group differences. The P value will be adjusted using the O'Brien & Fleming method for multiple comparisons. EXPECTED OUTCOMES: The primary outcomes are total efficacy rate of PUD treatment, quality of ulcer healing, and changes in spleen qi deficiency symptoms. The secondary outcomes include ulcer area, PUD recurrence, Helicobacter pylori eradication rate, gastric function, body weight, and body mass index. Adverse events (AEs), severe AEs, treatment-related AEs, and withdrawal owing to AEs will be recorded to assess treatment safety. DISCUSSION: The trial results will provide high-quality evidence for HGMX, as a complementary therapy, for the long-term management of PUD and will be valuable for the development of related guidelines and regulations. TRIAL REGISTRATION: The protocol of this trial was approved in all research hospitals and was registered in ClinicalTrials.gov at October 25, 2017(No. NCT03320538).


Assuntos
Antiulcerosos/efeitos adversos , Antiulcerosos/uso terapêutico , Medicamentos de Ervas Chinesas/efeitos adversos , Medicamentos de Ervas Chinesas/uso terapêutico , Úlcera Péptica/tratamento farmacológico , Método Duplo-Cego , Quimioterapia Combinada , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori , Humanos , Úlcera Péptica/microbiologia , Prevenção Secundária
18.
BMJ Open ; 9(7): e022670, 2019 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-31289046

RESUMO

OBJECTIVE: To investigate whether the association between in vitro fertilisation (IVF) and severe maternal morbidity (SMM) was mediated by multiple gestations. DESIGN: A retrospective cohort study. SETTING: The study was conducted at six hospitals in China. PARTICIPANTS: Pregnant women at 20 gestational weeks or longer. OUTCOME MEASURE: The outcome was SMM, which was a composite of potential life-threatening conditions, the use of critical medical interventions, or the status of maternal near-miss that occurred during pregnancy, childbirth or within 42 days of pregnancy termination, as defined by WHO. RESULTS: In total, 22 368 eligible pregnant women were included, among whom 497 (2.2%) received IVF, and 776 developed SMM (incidence 34.7/1000 live births, 95% CI 32.3/1000 to 37.1/1000). Four multivariable logistic regression models were constructed. Model 1, without including the variable of multiple gestations, showed that IVF was associated with higher risk of SMM (adjusted OR (aOR) 1.54, 95% CI 1.03 to 2.29). Model 2, assessing the association between IVF and multiple gestations, showed that IVF was strongly associated with multiple gestations (aOR 14.75, 95% CI 11.38 to 19.10). Model 3, by adding the variable of multiple gestations to model 1, showed that IVF was not statistically associated with SMM (aOR 0.89, 95% CI 0.58 to 1.36), but multiple gestations were associated with higher risk of SMM (aOR 5.92, 95% CI 4.88 to 7.83). Model 4, investigating the association between IVF and SMM among singleton pregnancies, showed no statistically significant association (aOR 0.70, 95% CI 0.37 to 1.32). An additional analysis by adding the interaction term of IVF by multiple gestations to model 3 showed no statistical significance of the interaction term (aOR 1.15, 95% CI 0.36 to 3.68), confirming the absence of exposure-mediator interaction. CONCLUSIONS: Using the established rule for judging mediation effect, the results suggested that multiple gestations might mediate the association between the use of IVF and higher risk of SMM. Further prospective studies are warranted to test our finding.

20.
Mater Sci Eng C Mater Biol Appl ; 103: 109807, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31349397

RESUMO

Hydroxyapatite (HAP) is not only a common component of most idiopathic CaOx stones, but also the core of Randall's plaque. HAP is a nest that can induce the formation of Randall's plaques and even kidney stones. We studied the toxic effects and mechanisms of four different types of nano-HAP crystals (H-Sphere, 72.5 nm × 72.5 nm; H-Needle, 37.2 nm × 162.7 nm; H-Rod, 42.3 nm × 115.3 nm; and H-Plate, 145.5 nm × 272.9 nm) on human renal proximal tubular epithelial cells (HK-2). HAP crystals could cause oxidative stress that triggered a series of cell dysfunction problems, resulting in decreased cell viability, loss of cell membrane integrity, cell swelling, and cell necrosis. The toxic effect of HAP was mainly attributed to its entry into cell by endocytosis and its accumulation in the lysosomes, causing the level of intracellular reactive oxygen species (ROS) to rise, the mitochondrial membrane potential (Δψm) to decrease, the lysosomal integrity to be destroyed, and the cell cycle blocked during the G0/G1 phase. The cytotoxicity of the four kinds of HAP crystals was ranked as follows: H-Sphere > H-Needle > H-Rod > H-Plate. The cytotoxicity of each crystal was positively correlated with low absolute zeta potential, conduciveness to internalized morphology, large specific surface area and aspect ratio, and small particle size. These results indicated that nano-HAP could damage HK-2 cells, and the physical properties of HAP crystals play a vital effect in their cytotoxicity.

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