This study aims to quantitatively summarize the association between night shift work and the risk of metabolic syndrome (MetS), with special reference to the dose–response relationship with years of ...night shift work. We systematically searched all observational studies published in English on PubMed and Embase from 1971 to 2013. We extracted effect measures (relative risk, RR; or odd ratio, OR) with 95% confidence interval (CI) from individual studies to generate pooled results using meta‐analysis approach. Pooled RR was calculated using random‐ or fixed‐effect model. Downs and Black scale was applied to assess the methodological quality of included studies. A total of 13 studies were included. The pooled RR for the association between ‘ever exposed to night shift work’ and MetS risk was 1.57 (95% CI = 1.24–1.98, pₕₑₜₑᵣₒgₑₙₑᵢₜy = 0.001), while a higher risk was indicated in workers with longer exposure to night shifts (RR = 1.77, 95% CI = 1.32–2.36, pₕₑₜₑᵣₒgₑₙₑᵢₜy = 0.936). Further stratification analysis demonstrated a higher pooled effect of 1.84 (95% CI = 1.45–2.34) for studies using the NCEP‐ATPIII criteria, among female workers (RR = 1.61, 95% CI = 1.10–2.34) and the countries other than Asia (RR = 1.65, 95% CI = 1.39–1.95). Sensitivity analysis confirmed the robustness of the results. No evidence of publication bias was detected. The present meta‐analysis suggested that night shift work is significantly associated with the risk of MetS, and a positive dose–response relationship with duration of exposure was indicated.
Let-7 miRNAs are involved in carcinogenesis and tumor progression through their roles in maintaining differentiation and normal development. However, there is little research focusing on the effects ...of let-7 on Wnt-activated self-renewal of breast cancer stem cells. By analyzing the expression levels of let-7 family members in clinical tissues, we found that higher expression levels of let-7b and let-7c were correlated with better clinical prognosis of patients with estrogen receptor (ER)α-positive breast tumor. Further, we found that only let-7c was inversely correlated with ERα expression, and there is corelationship between let-7c and Wnt signaling in clinical tissues. Aldehyde dehydrogenase (ALDH)1 sorting and mammosphere formation assays showed that let-7c inhibited the self-renewal of stem cells in ERα-positive breast cancer. Let-7c decreased ERα expression through directly binding to the 3'UTR (untranslated region), and let-7c inhibited the estrogen-induced activation of Wnt signaling. Depletion of ERα abolished let-7c functions in stem cell signatures, which further confirmed that let-7c inhibited estrogen-induced Wnt activity through decreasing ERα expression. Taken together, our findings identified a biochemical and functional link between let-7c with ERα/Wnt signaling in breast cancer stem cells.
Abstract
Stimuli-responsive behaviors of flexible metal–organic frameworks (MOFs) make these materials promising in a wide variety of applications such as gas separation, drug delivery, and molecular ...sensing. Considerable efforts have been made over the last decade to understand the structural changes of flexible MOFs in response to external stimuli. Uniform pore deformation has been used as the general description. However, recent advances in synthesizing MOFs with non-uniform porous structures, i.e. with multiple types of pores which vary in size, shape, and environment, challenge the adequacy of this description. Here, we demonstrate that the CO
2
-adsorption-stimulated structural change of a flexible MOF, ZIF-7, is induced by CO
2
migration in its non-uniform porous structure rather than by the proactive opening of one type of its guest-hosting pores. Structural dynamics induced by guest migration in non-uniform porous structures is rare among the enormous number of MOFs discovered and detailed characterization is very limited in the literature. The concept presented in this work provides new insights into MOF flexibility.
Background There has been no study on antibiotic‐resistant Propionibacterium acnes in Hong Kong.
Objective We investigated the prevalence and pattern of antibiotic‐resistant P. acnes and to ...identify any associated factors for harbouring the resistant strains.
Methods Culture and sensitivity testing of P. acnes to commonly used antibiotics were performed. Resistance to tetracycline was defined at a minimal inhibitory concentration (MIC) of 2 μg/mL or more; erythromycin at an MIC of 0.5 μg/mL or more; clindamycin at an MIC of 0.25 μg/mL or more according to EUCAST. For breakpoints of doxycycline and minocycline, those with an MIC of 1 μg/mL or more were defined as resistant strains.
Results Among the 111 specimens collected from 111 patients, 86 strains of P. acnes were recovered, one from each specimen. Twenty‐five specimens had no growth. Forty‐seven (54.8%) strains were found to be resistant to one or more antibiotics. Forty‐six (53.5%), 18 (20.9%), 14 (16.3%), 14(16.3%) and 14 (16.3%) strains were resistant to clindamycin (CL), erythromycin (EM), tetracycline (TET), doxycycline (DOX) and minocycline (MR) respectively. Ten strains (11.6%) had cross resistance between the MLS antibiotics (erythromycin or clindamycin), one strain (1.2%) had cross resistance among the cyclines and 14 strains (16.4%) had cross resistance between the MLS and cycline antibiotics. Binary logistic regression showed an association between MLS antibiotic resistance with an increased age whereas cycline resistance was associated with the duration of treatment.
Conclusions Antibiotic‐resistant P. acnes is prevalent in Hong Kong. Dermatologists should be more vigilant in prescribing antibiotics for acne patients.
The nonlinear optical property of few-layered MoS₂ nanoplatelets synthesized by the hydrothermal exfoliation method was investigated from the visible to the near-infrared band using lasers. Both ...open-aperture Z-scan and balanced-detector measurement techniques were used to demonstrate the broadband saturable absorption property of few-layered MoS₂. To explore its potential applications in ultrafast photonics, we fabricated a passive mode locker for ytterbium-doped fibre laser by depositing few-layered MoS₂ onto the end facet of optical fiber by means of an optical trapping approach. Our laser experiment shows that few-layer MoS₂-based mode locker allows for the generation of stable mode-locked laser pulse, centered at 1054.3 nm, with a 3-dB spectral bandwidth of 2.7 nm and a pulse duration of 800 ps. Our finding suggests that few-layered MoS₂ nanoplatelets can be useful nonlinear optical material for laser photonics devices, such as passive laser mode locker, Q-switcher, optical limiter, optical switcher and so on.
Despite being one of the most promising candidates for grid‐level energy storage, practical aqueous zinc batteries are limited by dendrite formation, which leads to significantly compromised safety ...and cycling performance. In this study, by using single‐crystal Zn‐metal anodes, reversible electrodeposition of planar Zn with a high capacity of 8 mAh cm−2 can be achieved at an unprecedentedly high current density of 200 mA cm−2. This dendrite‐free electrode is well maintained even after prolonged cycling (>1200 cycles at 50 mA cm−2). Such excellent electrochemical performance is due to single‐crystal Zn suppressing the major sources of defect generation during electroplating and heavily favoring planar deposition morphologies. As so few defect sites form, including those that would normally be found along grain boundaries or to accommodate lattice mismatch, there is little opportunity for dendritic structures to nucleate, even under extreme plating rates. This scarcity of defects is in part due to perfect atomic‐stitching between merging Zn islands, ensuring no defective shallow‐angle grain boundaries are formed and thus removing a significant source of non‐planar Zn nucleation. It is demonstrated that an ideal high‐rate Zn anode should offer perfect lattice matching as this facilitates planar epitaxial Zn growth and minimizes the formation of any defective regions.
Zinc‐metal anodes, which are desirable for various aqueous zinc battery chemistries, degrade over repeated cycling due to dendrite growth. It is found that dendrites can be prevented by ensuring no defective regions form during zinc deposition, thus removing sites for dendrite nucleation and ensuring purely planar deposition. This allows unprecedentedly high charging rates to be achieved.
Imaging of the islet neural network Tang, S.-C.; Peng, S.-J.; Chien, H.-J.
Diabetes, obesity & metabolism,
September 2014, Letnik:
16, Številka:
S1
Journal Article
The islets of Langerhans receive signals from the circulation and nerves to modulate hormone secretion in response to physiological cues. Although the rich islet innervation has been documented in ...the literature dating as far back as Paul Langerhans' discovery of islets in the pancreas, it remains a challenging task for researchers to acquire detailed islet innervation patterns in health and disease due to the dispersed nature of the islet neurovascular network. In this article, we discuss the recent development of 3‐dimensional (3D) islet neurohistology, in which transparent pancreatic specimens were prepared by optical clearing to visualize the islet microstructure, vasculature and innervation with deep‐tissue microscopy. Mouse islets were used as an example to illustrate how to apply this 3D imaging approach to characterize (i) the islet parasympathetic innervation, (ii) the islet sympathetic innervation and its reinnervation after transplantation under the kidney capsule and (iii) the reactive cellular response of the Schwann cell network in islet injury. While presenting and characterizing the innervation patterns, we also discuss how to apply the signals derived from transmitted light microscopy, vessel painting and immunostaining of neural markers to verify the location and source of tissue information. In summary, the systematic development of tissue labelling, clearing and imaging methods to reveal the islet neuroanatomy offers insights to help study the neural‐islet regulatory mechanisms and the role of neural tissue remodelling in the development of diabetes.
Abstract
Nickel-based complex oxides have served as a playground for decades in the quest for a copper-oxide analog of the high-temperature superconductivity. They may provide clues towards ...understanding the mechanism and an alternative route for high-temperature superconductors. The recent discovery of superconductivity in the infinite-layer nickelate thin films has fulfilled this pursuit. However, material synthesis remains challenging, direct demonstration of perfect diamagnetism is still missing, and understanding of the role of the interface and bulk to the superconducting properties is still lacking. Here, we show high-quality Nd
0.8
Sr
0.2
NiO
2
thin films with different thicknesses and demonstrate the interface and strain effects on the electrical, magnetic and optical properties. Perfect diamagnetism is achieved, confirming the occurrence of superconductivity in the films. Unlike the thick films in which the normal-state Hall-coefficient changes signs as the temperature decreases, the Hall-coefficient of films thinner than 5.5 nm remains negative, suggesting a thickness-driven band structure modification. Moreover, X-ray absorption spectroscopy reveals the Ni-O hybridization nature in doped infinite-layer nickelates, and the hybridization is enhanced as the thickness decreases. Consistent with band structure calculations on the nickelate/SrTiO
3
heterostructure, the interface and strain effect induce a dominating electron-like band in the ultrathin film, thus causing the sign-change of the Hall-coefficient.
PDF
