The conversion of methane to more valuable chemicals is one of the most intensively studied topics in catalysis. The direct conversion of methane is attractive because the process is simple, but ...unfortunately its products are chemicals that are more reactive than methane. The current status of this research field is discussed with an emphasis on C–H bond activation and future challenges.
In this study, a novel Co3O4/Co(OH)2 heterostructure is obtained via electrodeposition on nickel (Ni) foam, forming sandwich‐like structure and freestanding electrode. The outer Co(OH)2 with layered ...structure can provide sufficient absorption sites and enable facile ion intercalation, meanwhile the presence of a conductive and robust interfacial Co3O4 layer between Ni foam and Co(OH)2 is found effectively minimizes the charge transfer resistance and stabilizes the interface, thus improving the electrode's rate and cycling performance with high capacity preserved synergistically. Furthermore, the structural evolution of Co(OH)2 and Co3O4 upon cycling are elucidated systematically using a series of in situ and ex situ techniques. The Co(OH)2 is found irreversibly changed to CoOOH upon first charge, which is then reversibly converted to CoO2 during the subsequent charge–discharge cycles. The Co3O4 exhibits negligible phase changes of the bulk upon cycling, indicating its good structural integrity that contributes to the significantly improved cyclability. In general, this work not only offers an ease and effective approach to optimize the charge storage properties of Co3O4/Co(OH)2 heterostructure via interfacial layer control, but also provides valuable insights in understanding their charge storage mechanisms, which may inspire the development of more heterostructures or extend to other applications.
Interfacial layer control of freestanding sandwich‐like Co3O4/Co(OH)2 heterostructure is reported as a generalized and effective approach to optimize the electrode's charge storage properties, leading to improved rate and cycle performance. This work also provides valuable insights in understanding the charge storage mechanisms of Co3O4 and Co(OH)2, which will promote the rational design of more heterostructures with excellent electrochemical performance.
There was much evidence suggesting that the serum lactate dehydrogenase (LDH) levels reflect the extent of various pathophysiological processes. However, the current information about dynamic change ...of LDH in COVID-19 pneumonia has not been well investigated.
Study was performed in 87 cases confirmed by COVID-19 infection. The serum LDH levels were determined at diagnosis and follow-up visits. The evaluation of clinical response to therapy was based on chest CT scan. We selected the value of LDH around the data of chest CT scan (- 1 ~ + 1 day).
At diagnosis, significant differences in LDH levels were found between non-severe and severe group (P < 0.05). It was demonstrated that increase or decrease of LDH was indicative of radiographic progress or improvement (P < 0.05). The time to LDH normalization (5.67 ± 0.55, days) was positively correlated with the time to radiographic absorption (5.57 ± 0.65 days, r = 0.53, P < 0.05). Applying the cut-off value of the increase in LDH has good specificity to predict disease progression.
Serum LDH was validated for its potential usefulness as markers for evaluating clinical severity and monitoring treatment response in COVID-19 pneumonia.
Experiments have demonstrated the regulation of long noncoding RNA (lncRNA) in tuberculosis (TB), and negative pressure treatment has been associated with the alleviation of TB. Here, we investigated ...the interaction of negative pressure and the lncRNA X‐inactive specific transcript (XIST) in modulating Mycobacterium tuberculosis (MTB) infection. Initially, we established an in vitro cell model of MTB infection and an in vivo mouse model of MTB infection, followed by treatment with negative pressure. Then, we examined the expression of XIST, followed by analysis of the downstream miRNA of XIST. XIST was overexpressed or underexpressed through cell transfection to examine its effects on macrophage polarization via the miR–125b–5p/A2 axis. The MTB models were characterized by upregulated XIST and downregulated miR‐125b‐5p. XIST bound to miR‐125b‐5p, leading to its downregulation, and thus causing higher MTB survival in an ESAT‐6–dependent manner. Additionally, negative pressure treatment decreased MTB‐driven XIST expression through downregulation of A20 (an NF‐κB repressor) via miR‐125b‐5 expression, promoting the M1 polarization program in macrophages through activation of the NF‐κB pathway. In summary, negative pressure treatment after MTB infection can promote the polarization of macrophages to the proinflammatory M1 phenotype by regulating the XIST/miR–125b–5p/A20/NF–κB axis.
Experiments have demonstrated the regulation of long noncoding RNA (lncRNA) in tuberculosis (TB), and negative pressure treatment has been associated with the alleviation of TB. Here, we investigated the interaction of negative pressure and the lncRNA X‐inactive specific transcript (XIST) in modulating Mycobacterium tuberculosis (MTB) infection.
Robots in orthopedic surgery have been developed rapidly for decades and bring significant benefits to the patients and healthcare providers. However, robotics in fracture reduction remains at the ...infant stage. As essential components of the current robotic system, external fixators were used in fracture reduction, including the unilateral and Ilizarov-like ring fixators. With emerging of the industrial robots and mechanical arms, their sterilized variants were developed as the serial robots, including the traction device and robotic arm, for fracture reduction. Besides, parallel robots (e.g., Gough–Stewart platform) were devised for lower extremity traction and fracture reduction. After combining the advantages of the serial and parallel mechanisms, hybrid robots can fulfill specific clinical requirements (e.g., the joint fracture, including multiple major fragments). Furthermore, with the aid of intra-operative navigation systems, fracture reduction can be performed under real-time guidance. The paper presents a comprehensive overview of the advancement of the robots in fracture reduction and evaluates research challenges and future perspectives, including ergonomic and economic issues, operation time, artificial realities and intelligence, and telesurgery.
Statins are widely used to treat people with metabolic and cardiovascular disorders. The effect of statins on coronavirus disease 2019 (COVID-19) is unclear. To investigate the association between ...statins and COVID-19 outcomes and, if possible, identify the subgroup population that benefits most from statin use.
A systematic review and meta-analysis of published studies that included statin users and described COVID-19 outcomes through 10 November 2020. This study used the generic inverse variance method to perform meta-analyses with random-effects modelling. The main outcomes were evaluation of the need for invasive mechanical ventilator (IMV) support, the need for intensive care unit (ICU) care and death. All outcomes were measured as dichotomous variables.
A total of 28 observational studies, covering data from 63,537 individuals with COVID-19, were included. The use of statins was significantly associated with decreased mortality (odds ratio OR = 0.71, 95% confidence interval CI: 0.55-0.92, I
2
=72%) and the need for IMV (OR = 0.81, 95% CI: 0.69-0.95, I
2
=0%) but was not linked to the need for ICU care (OR = 0.91, 95% CI: 0.55-1.51, I
2
=66%). Subgroup analysis further identified five types of studies in which statin users had even lower odds of death.
The use of statins was significantly associated with a reduced need for IMV and decreased mortality among individuals with COVID-19. Statins may not need to be discontinued because of concern for COVID-19 on admission. Further randomized controlled trial (RCTs) are needed to clarify the causal effect between statin use and severe COVID-19 outcomes.
Key messages
Participants in five types of studies were shown to have even lower odds of death when taking statins.
The use of statins was significantly associated with a reduced need for invasive mechanical ventilation and decreased all-cause mortality among individuals with COVID-19. However, statin use did not prevent participants from needing care in the intensive care unit.
The results justify performing randomized controlled trials (RCTs) to validate the benefits of statins on COVID-19 outcomes.
As the key intermediate phase of crystalline calcium carbonate biominerals, amorphous calcium carbonate (ACC) remains mysterious in its structures because of its long‐range disorder and instability. ...We herein report the synthesis of ACC nanospheres in a water‐deficient organic solvent system. The obtained ACC nanospheres are very stable under dry conditions. Cryo‐TEM reveals that each nanospheres consists of smaller nanosized clusters. We further demonstrate that these clusters can precipitate on other substrates to form an ultrathin ACC coating, which should be an ACC cluster monolayer. The results demonstrate that the presence of small ACC clusters as the subunits of larger aggregates is inherent to ACC synthesized in water‐alcohol system but not induced by polymer additives.
Amorphous calcium carbonate(ACC) nanoparticles are synthesized in water‐deficient ethanol solution. The nanoparticles consist of tiny clusters as revealed by cryo‐TEM. ACC can aggregate on templates such as graphene oxide nanosheets. These findings provide a theoretical basis for controlled synthesis of ACC and a strategy to fabricate ultrathin mineral coatings on different substrates.
Objective
Radiotherapy (RT) for head and neck cancer (HNC) within 7 days of tooth extraction is contraindicated because it may increase the risk of osteoradionecrosis of the jaw (ORNJ). However, ...delayed RT could compromise survival in patients with HNC. By using a national healthcare database, we reviewed the contraindications and analysed other risk factors for ORNJ.
Design
A retrospective cohort study.
Setting
By using Taiwan's National Health Insurance Research Database, 5,062 HNC patients with at least one tooth extraction 1‐21 days before the first RT day (index day) and without any extractions during or after RT from 2000 to 2013 were included. The patients were divided into two groups according to the time of tooth extraction before the index day: 1‐7 days and 8‐21 days.
Participants
Taiwanese patients with head and neck cancer.
Main Outcomes Measure
Univariate and multivariate Cox proportional hazard regression models were used to evaluate the risk factors of ORNJ.
Results
The overall incidence of ORNJ in the included patients was 1.03% (mean follow‐up duration, 4.07 ± 3.01 years; range, 1.00‐13.99 years). Tooth extraction within 7 days before RT was not associated with increased ORNJ risk (hazard ratio HR =0.734; P = .312). Significant risk factors for ORNJ included oral cancer (adjusted HR = 3.961), tumour excision surgery within 3 months before RT (adjusted HR = 3.488) and mandibulectomy within 3 months before RT (adjusted HR = 5.985; all P < .001).
Conclusion
In a mean follow‐up of 4 years, tooth extraction within 7 days before RT for HNC treatment did not increase the ORNJ risk compared with tooth extraction 7‐21 days before RT.
The mammalian hair follicle arises during embryonic development from coordinated interactions between the epidermis and dermis. It is currently unclear how to recapitulate hair follicle induction in ...pluripotent stem cell cultures for use in basic research studies or in vitro drug testing. To date, generation of hair follicles in vitro has only been possible using primary cells isolated from embryonic skin, cultured alone or in a co-culture with stem cell-derived cells, combined with in vivo transplantation. Here, we describe the derivation of skin organoids, constituting epidermal and dermal layers, from a homogeneous population of mouse pluripotent stem cells in a 3D culture. We show that skin organoids spontaneously produce de novo hair follicles in a process that mimics normal embryonic hair folliculogenesis. This in vitro model of skin development will be useful for studying mechanisms of hair follicle induction, evaluating hair growth or inhibitory drugs, and modeling skin diseases.
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•Skin organoids can be generated from mPSCs under defined conditions•Skin organoids are composed of self-assembled epidermal and dermal layers•Skin organoids produce hair follicles, sebaceous glands, and adipocytes•Hair follicle induction from skin organoids mimics normal hair folliculogenesis
Lee at el. describe a defined in vitro 3D culture system that generates skin organoids from mouse pluripotent stem cells. The skin organoids contain self-organized skin layers and skin appendages, including hair follicles, sebaceous glands, and adipocytes.
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