Hydrocephalus is a common complication of aneurysmal subarachnoid hemorrhage (aSAH) and reportedly contributes to poor neurological outcomes. In this review, we summarize the molecular and cellular ...mechanisms involved in the pathogenesis of hydrocephalus following aSAH and summarize its treatment strategies. Various mechanisms have been implicated for the development of chronic hydrocephalus following aSAH, including alterations in cerebral spinal fluid (CSF) dynamics, obstruction of the arachnoid granulations by blood products, and adhesions within the ventricular system. Regarding molecular mechanisms that cause chronic hydrocephalus following aSAH, we carried out an extensive review of animal studies and clinical trials about the transforming growth factor-β/SMAD signaling pathway, upregulation of tenascin-C, inflammation-dependent hypersecretion of CSF, systemic inflammatory response syndrome, and immune dysregulation. To identify the ideal treatment strategy, we discuss the predictive factors of shunt-dependent hydrocephalus between surgical clipping and endovascular coiling groups. The efficacy and safety of other surgical interventions including the endoscopic removal of an intraventricular hemorrhage, placement of an external ventricular drain, the use of intraventricular or cisternal fibrinolysis, and an endoscopic third ventriculostomy on shunt dependency following aSAH were also assessed. However, the optimal treatment is still controversial, and it necessitates further investigations. A better understanding of the pathogenesis of acute and chronic hydrocephalus following aSAH would facilitate the development of treatments and improve the outcome.
Traditional lithium‐ion batteries that are based on layered Li intercalation electrode materials are limited by the intrinsically low theoretical capacities of both electrodes and cannot meet the ...increasing demand for energy. A facile route for the synthesis of a new type of composite nanofibers, namely carbon nanofibers decorated with molybdenum disulfide sheets (CNFs@MoS2), is now reported. A synergistic effect was observed for the two‐component anode, triggering new electrochemical processes for lithium storage, with a persistent oxidation from Mo (or MoS2) to MoS3 in the repeated charge processes, leading to an ascending capacity upon cycling. The composite exhibits unprecedented electrochemical behavior with high specific capacity, good cycling stability, and superior high‐rate capability, suggesting its potential application in high‐energy lithium‐ion batteries.
Carbon nanofibers (CNFs) decorated with molybdenum disulfide sheets are fabricated by a facile hydrothermal process with low‐cost, biomass‐derived carbonaceous nanofibers as the supports. On reacting with lithium, the nanofibers undergo novel electrochemical processes that are triggered by a synergistic lithium storage effect, leading to enhanced cycling and rate performance of the lithium‐ion battery.
A series of monodisperse six‐armed conjugated starbursts (Tr1F, Tr2F, and Tr3F) containing a truxene core and multibranched oligofluorene bridges capped with diphenylamine (DPA) units has been ...designed, synthesized, and investigated as robust gain media for organic semiconductor lasers (OSLs). The influence of electron‐rich DPA end groups on their optoelectronic characteristics has been discussed at length. DPA cappers effectively raise HOMO levels of the starbursts, thus enhancing the hole injection and transport ability. Solution‐processed electroluminescence devices based on the resulting six‐armed starbursts exhibited efficient deep‐blue electroluminescence with clear reduced turn‐on voltages (3.2–3.5 V). Moreover, the resulting six‐armed molecules showed stabilized electroluminescence and amplified spontaneous emission with low thresholds (27.4–63.9 nJ pulse−1), high net gain coefficients (80.1–101.3 cm−1), and small optical loss (2.6–4.4 cm−1). Distributed feedback OSLs made from Tr3F exhibited a low lasing threshold of 0.31 kW cm−2 (at 465 nm). The results suggest that the construction of truxene‐centered six‐armed conjugated starbursts with the incorporation of DPA units can effectively enhance EL properties by precisely regulating the HOMO energy levels, and further optimizing their optical gain properties.
Bursting of stars: Monodisperse six‐armed starburst conjugated molecules with diphenylamine (DPA) end‐cappers were synthesized, and their optical gain and lasing characteristics were investigated. The incorporation of DPA end groups effectively raised the HOMO levels, thus enhancing the hole injection and transport ability. The resulting starbursts manifested stable optical gain and lasing performance with low thresholds (27.4–63.9 nJ pulse−1), high net gain coefficients (80.1–101.3 cm−1) and small waveguide loss (2.6–4.4 cm−1).
A
bstract
The inelastic dark matter model is one kind of popular models for the light dark matter (DM) below
O
(1) GeV. If the mass splitting between DM excited and ground states is small enough, the ...co-annihilation becomes the dominant channel for thermal relic density and the DM excited state can be long-lived at the collider scale. We study scalar and fermion inelastic dark matter models for
O
(1) GeV DM at Belle II with U(1)
D
dark gauge symmetry broken into its
Z
2
subgroup. We focus on dilepton displaced vertex signatures from decays of the DM excited state. With the help of precise displaced vertex detection ability at Belle II, we can explore the DM spin, mass and mass splitting between DM excited and ground states. Especially, we show scalar and fermion DM candidates can be discriminated and the mass and mass splitting of DM sector can be determined within the percentage of deviation for some benchmark points. Furthermore, the allowed parameter space to explain the excess of muon (
g
−
2)
μ
is also studied and it can be covered in our displaced vertex analysis during the early stage of Belle II experiment.
The onset of prostate cancer (PCa) is often hidden, and recurrence and metastasis are more likely to occur due to chemotherapy resistance. Herein, we identified downregulated long noncoding RNA ...(lncRNA) growth arrest-specific 5 (GAS5) in PCa that was associated with metastasis and paclitaxel resistance. GAS5 acted as a tumor suppressor in suppressing the proliferation and metastasis of paclitaxel-resistant PCa cells. GAS5 overexpression in vivo inhibited the tumor growth of xenografts and elevated PCa sensitivity to paclitaxel. Combination of GAS5 and paclitaxel treatment showed great potential in PCa treatment. Moreover, mechanistic analysis revealed a novel regulatory network of GAS5/miR-18a-5p/serine/threonine kinase 4 (STK4) that inhibits epithelial-to-mesenchymal transition (EMT) and enhances tumor stem cell-like-mediated sensitivity to paclitaxel in PCa. These findings provide a novel direction for the development of a potential adjunct to cancer chemotherapy that aims to improve the sensitivity of chemotherapy drugs in PCa.
Aims
To evaluate the association between glucagon‐like peptide‐1 receptor agonists (GLP‐1 RAs) and the risk of bone fracture in patients with type 2 diabetes mellitus (T2DM).
Materials and methods
We ...conducted a systematic literature search in PubMed, Embase, the Cochrane Library, and Web of Science from inception to 28 February 2018 and identified eligible randomized controlled trials. The following data were extracted from each study: first author, year of publication, sample size, patient characteristics, study design, intervention drug, control drug, follow‐up time, and incident bone fracture events. A meta‐analysis was conducted using Review Manager 5.3 software to calculate the odds ratio (OR) and 95% confidence intervals (CI) for dichotomous variables.
Results
A total of 38 studies with 39 795 patients with T2DM were included. There were 241 incident bone fracture cases (107 in the GLP‐1 RAs group and 134 in the control group). Compared with patients who received placebo and other anti‐diabetic drugs, those who received GLP‐1 RAs treatment showed a pooled OR of 0.71 (95% CI, 0.56‐0.91) for bone fracture. Subgroup analysis showed that treatments with liraglutide and lixisenatide were associated with significantly reduced risk of bone fractures (ORs, 0.56; 95% CI, 0.38‐0.81 and 0.55; 95% CI, 0.31‐0.97, respectively). However, other GLP‐1 RAs did not show superiority to placebo or other anti‐diabetic drugs. Moreover, these beneficial effects were dependent on the duration of GLP‐1 RAs treatment, only a GLP‐1 RAs treatment period of more than 52 weeks could significantly lower the risk of bone fracture in patients with T2DM (OR, 0.71; 95% CI, 0.56‐0.91).
Conclusions
Compared with placebo and other anti‐diabetic drugs, liraglutide and lixisenatide were associated with a significant reduction in the risk of bone fractures, and the beneficial effects were dependent on the duration of treatment.
The error-free and efficient repair of DNA double-stranded breaks (DSBs) is extremely important for cell survival. RNA has been implicated in the resolution of DNA damage but the mechanism remains ...poorly understood. Here, we show that miRNA biogenesis enzymes, Drosha and Dicer, control the recruitment of repair factors from multiple pathways to sites of damage. Depletion of Drosha significantly reduces DNA repair by both homologous recombination (HR) and non-homologous end joining (NHEJ). Drosha is required within minutes of break induction, suggesting a central and early role for RNA processing in DNA repair. Sequencing of DNA:RNA hybrids reveals RNA invasion around DNA break sites in a Drosha-dependent manner. Removal of the RNA component of these structures results in impaired repair. These results show how RNA can be a direct and critical mediator of DNA damage repair in human cells.
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•New 2D/2D Z-scheme heterostructure photocatalyst BiOBr/TzDa COF (BTDC) is prepared.•RhB degradation or Cr(VI) reduction is achieved by BTDC under visible-light.•BTDC can ...simultaneously remove RhB/Cr(VI) mixture with synergistic effect.•BTDC has good stability and reusability in cyclic use on RhB and Cr(VI) removal.•Mechanisms for RhB degradation and Cr(VI) reduction by BTDC are proposed.
Design of efficient Z-scheme heterojunction photocatalysts is important and yet challenging for purifying wastewater with solar energy. Herein, a new 2D/2D Z-scheme heterostructure photocatalyst of BiOBr/TzDa covalent organic framework (COF) composite was obtained by modification of 2D BiOBr with 2D TzDa COF via a facile hydrothermal method. The photocatalytic activity of BiOBr/TzDa COF (BTDC) under simulated visible light was studied by degradation of single Rhodamine B (RhB) (10 ppm) and reduction of single Cr(VI) (10 ppm), as well as for treating the RhB/Cr(VI) mixture. RhB could be efficaciously degraded by BTDC within a wide pH range of 2.1–8.1. Nearly complete reduction of Cr(VI) at pH 2.1 could also be achieved after irradiation for 90 min. Moreover, much higher performance of BTDC was found for simultaneous removal of RhB and Cr(VI) from a binary mixture solution than for single pollutant system due to the synergistic effect within the RhB/Cr(VI)/BTDC system. 97% of total RhB and Cr(VI) in the mixture could be removed in 20 min and 40 min, respectively. The promoted efficiency of the stable and recyclable BTDC could be mainly attributed to accelerated charge carriers separation and transport, enhanced visible light absorption as well as increased specific surface area. Photocatalytic mechanism with Z-scheme charge transfer in BTDC was suggested based on systematic studies of band structures calculation, radical quenching experiments and ESR analyses. This study may provide a strategy in constructing COF based heterojunctions for purification of wastewaters containing mixed heavy metal ions and organic pollutants.
The reactions between peroxymonosulfate (PMS) and quinones were investigated for the first time in this work, where benzoquinone (BQ) was selected as a model quinone. It was demonstrated that BQ ...could efficiently activate PMS for the degradation of sulfamethoxazole (SMX; a frequently detected antibiotic in the environments), and the degradation rate increased with solution pH from 7 to 10. Interestingly, quenching studies suggested that neither hydroxyl radical (•OH) nor sulfate radical (SO4 •–) was produced therein. Instead, the generation of singlet oxygen (1O2) was proved by using two chemical probes (i.e., 2,2,6,6-tetramethyl-4-piperidinol and 9,10-diphenylanthracene) with the appearance of 1O2 indicative products detected by electron paramagnetic resonance spectrometry and liquid chromatography mass spectrometry, respectively. A catalytic mechanism was proposed involving the formation of a dioxirane intermediate between PMS and BQ and the subsequent decomposition of this intermediate into 1O2. Accordingly, a kinetic model was developed, and it well described the experimental observation that the pH-dependent decomposition rate of PMS was first-order with respect to BQ. These findings have important implications for the development of novel nonradical oxidation processes based on PMS, because 1O2 as a moderately reactive electrophile may suffer less interference from background organic matters compared with nonselective •OH and SO4 •–.
1,4-Butanediol (BD) is an important chemical that is widely used in industry with an annual demand of one million metric tons. Here we report a modular development of engineered bacteria for ...successful BD bio-production. Using a systems engineering concept, we partitioned our development into two parts: namely BD biosynthesis and production control. The former was implemented through a de novo pathway that functions as an enzymatic reactor, while the latter was accomplished via synthetic circuits serving as genetic controllers. To facilitate development, the carbon utilizations were also partitioned into two routes. d-xylose was exclusively designated for BD production with other carbon sources utilized for cellular growth. Additionally, a quorum-sensing mechanism was exploited for production control, and the resulting strain was capable of autonomous production of BD. This study represents an example of the synergy between synthetic biology and metabolic engineering, affirming the need for deeper integration of the two fields.
•A de novo 1,4-butanediol (BD) biosynthesis pathway was designed and constructed.•The whole system consists of an enzymatic reactor and a genetic controller.•Carbon sources were orthogonally utilized for cellular growth and BD production.•Autonomous BD production was achieved using a quorum sensing system.•This work showcases the synergy between metabolic engineering and synthetic biology.
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