The current therapies to treat hepatitis B virus (HBV) infection are limited. Recently, clustered regularly interspaced short palindromic repeat (CRISPR) systems, originally identified in bacteria ...and archaea, have been found to consist of an RNA-based adaptive immune system that degrades complimentary sequences of invading plasmids and viruses. Here, we studied the effects of the CRISPR/CRISPR-associated Cas9 system that was targeted to the surface antigen (HBsAg)-encoding region of HBV, both in a cell culture system and in vivo. The HBsAg levels in the media of the cells and in the sera of mice were analyzed by a quantitative enzyme-linked immunosorbent assay. The HBV DNA levels were assessed by quantitative PCR and HBsAg expression in mouse livers was assessed by an immunohistochemical assay. The amount of HBsAg secreted in the cell culture and mouse serum was reduced by CRISPR/Cas9 treatment. Immunohistochemistry analyses showed almost no HBsAg-positive cells in the liver tissue of CRISPR/Cas9-S1+X3-treated mice. The CRISPR/Cas9 system efficiently produced mutations in HBV DNA. Thus, CRISPR/Cas9 inhibits HBV replication and expression in vitro and in vivo and may constitute a new therapeutic strategy for HBV infection.
Summary
Background
Up‐to‐date information regarding the recurrence rate of Helicobacter pylori (H. pylori) after eradication therapy is not available.
Aim
To evaluate the global recurrence rate ...following H. pylori eradication therapy and confirm its association with socioeconomic and sanitary conditions.
Methods
A systematic search of PubMed, EMBASE and the Cochrane library was performed to identify potentially relevant publications using the following keywords: “Helicobacter pylori” or “H. pylori” or “Hp” and “recurrence” or “recrudescence” or “reinfection” or “recurrent” or “recurred” or “re‐infect*” or “relapse*.”
Results
A total of 132 studies (53 934 patient‐years) were analysed. Each study was weighted according to the duration of patient‐years. The global annual recurrence, reinfection and recrudescence rate of H. pylori were 4.3% (95% CI, 4‐5), 3.1% (95% CI, 2‐5) and 2.2% (95% CI, 1‐3), respectively. The H. pylori recurrence rate was inversely related to the human development index (HDI) (ie, 3.1% 95% CI, 2‐4, 6.2% 95% CI, 4‐8 and 10.9% 95% CI, 6‐18 in countries with a very high, high and medium or low HDI) (P <.01) and directly related to H. pylori prevalence (10.9% 95% CI, 7‐16, 3.7% 95% CI, 3‐5, 3.4% 95% CI, 2‐5 and 1.6% 95% CI, 0.5‐3 in countries with a very high, high, medium or low local H. pylori prevalence) (P <.01). Global recurrence rates remained relatively stable between 1990s, 2000s and 2010s but varied across different regions (P <.05).
Conclusions
H. pylori recurrence remains a problem closely associated with socioeconomic and sanitary conditions. Methods to reduce recurrence in developing countries are needed.
Linked ContentThis article is linked to Willington and Gearry, and Roblin et al papers. To view these papers visit https://doi.org/10.1111/apt.14370 and https://doi.org/10.1111/apt.14385.
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.
The observation of magnetic interaction at the interface between nonmagnetic oxides has attracted much attention in recent years. In this report, we show that the Kondo-like scattering at the ...SrTiO3-based conducting interface is enhanced by increasing the lattice mismatch and growth oxygen pressure PO2. For the 26-unit-cell LaAlO3/SrTiO3 (LAO/STO) interface with lattice mismatch being 3.0%, the Kondo-like scattering is observed when PO2 is beyond 1 mTorr. By contrast, when the lattice mismatch is reduced to 1.0% at the (La0.3Sr0.7)(Al0.65Ta0.35)O3/SrTiO3 (LSAT/STO) interface, the metallic state is always preserved up to PO2 of 100 mTorr. The data from Hall measurement and X-ray absorption near edge structure (XANES) spectroscopy reveal that the larger amount of localized Ti(3+) ions are formed at the LAO/STO interface compared to LSAT/STO. Those localized Ti(3+) ions with unpaired electrons can be spin-polarized to scatter mobile electrons, responsible for the Kondo-like scattering observed at the LAO/STO interface.
Polyamines play an important role in stress response. In the pathway of polyamines synthesis, S-adenosylmethionine decarboxylase (SAMDC) is one of the key enzymes. In this study, a full length cDNA ...of SAMDC (AhSAMDC) was isolated from peanut (Arachis hypogaea L.). Phylogenetic analysis revealed high sequence similarity between AhSAMDC and SAMDC from other plants.
In peanut seedlings exposed to sodium chloride (NaCl), the transcript level of AhSAMDC in roots was the highest at 24 h that decreased sharply at 72 and 96 h after 150 mM NaCl treatment. However, the expression of AhSAMDC in peanut leaves was significantly inhibited, and the transcript levels in leaves were not different compared with control
These results implied the tissue‐specific and time-specific expression of AhSAMDC. The physiological effects and functional mechanism of AhSAMDC were further evaluated by overexpressing AhSAMDC in tobaccos. The transgenic tobacco lines exhibited higher germination rate and longer root length under salt stress. Reduced membrane damage, higher antioxidant enzyme activity, and higher proline content were also observed in the transgenic tobacco seedlings. What's more, AhSAMDC also led to higher contents of spermidine and spermine, which can help to scavenge reactive oxygen species.
Together, this study suggests that AhSAMDC enhances plant resistance to salt stress by improving polyamine content and alleviating membrane damage
AhSAMDC subcloned into tobacco plants may play an important role in alleviating oxidative stress and membrane damages by improving antioxidant enzymes under salt stress.
A dynamic pH junction was used in capillary electrophoresis (CE-DAD) to on-line preconcentrate, separate, and determine trace amounts of sulfonamide antibiotics (SAs) in milk and yoghurt samples in ...this study. A sample matrix with 0.15% acetic acid and 10% methanol (MeOH) at a pH of 4.0, and a background electrolyte (BGE) that contained 35 mM sodium citrate with 10% MeOH at a pH of 8.5, and an acidic barrage of 0.4% acetic acid with 10% MeOH at a pH of 2.5 were utilised to achieve a stacking effect for SAs through a dynamic pH junction. Under optimised conditions, the proposed preconcentration method showed good linearity (30–500 ng/mL, r2 ≥ 0.9940), low limits of detection (LODs) of 4.1–6.3 ng/mL, and acceptable analytes recovery (81.2–106.9%) with relative standard deviations (RSDs) within 5.3–13.7 (n = 9). The limits of quantification (LOQs) were below the maximum residue limit approved by the European Union (EU) in this type of matrices. Sensitivity enhancement factors of up to 129 were reached with the optimised dynamic pH junction using CE with a diode array detector (DAD). The method was used to determine SAs in fresh milk, low-fat milk, full-cream milk, and yoghurt samples.
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•Dynamic pH junction capillary electrophoresis for sulfonamide antibiotics analysis.•On-line sample stacking with sensitivity enhancement factors of up to 129.•Minimal sample pretreatment for milk and yoghurt samples.•LODs for SAs were 4.1–6.3 ng/mL with diode array detector.
Learning from a few examples (one/few-shot learning) on the fly is a key challenge for on-device machine intelligence. We present the first chip-level demonstration of one-shot learning with Stanford ...Associative memory for Programmable, Integrated Edge iNtelligence via life-long learning and Search (SAPIENS), a resistive random access memory (RRAM)-based non-volatile associative memory (AM) chip that serves as the backend for memory-augmented neural networks (MANNs). The 64-kb fully integrated RRAM-CMOS AM chip performs long-term feature embedding and retrieval, demonstrated on a 32-way one-shot learning task on the Omniglot dataset. Using only one example per class for 32 unseen classes during on-chip learning, SAPIENS achieves 79% measured inference accuracy on Omniglot, comparable to edge software model accuracy using five-level quantization (82%). It achieves an energy efficiency of 118 GOPS/W at 200 MHz for in-memory L1 distance computation and prediction. Multi-bank measurements on the same chip show that increasing the capacity from three banks (24 kb) to eight banks (64 kb) improves the chip accuracy from 73.5% to 79%, while minimizing the accuracy excursion due to bank-to-bank variability.
Semiconductor compounds are widely used for photocatalytic hydrogen production applications, where photogenerated electron-hole pairs are exploited to induce catalysis. Recently, powders of a ...metallic oxide (Sr
NbO
, 0.03<x<0.20) were reported to show competitive photocatalytic efficiencies under visible light, which was attributed to interband absorption. This discovery expanded the range of materials available for optimized performance as photocatalysts. Here we study epitaxial thin films of SrNbO
and find that their bandgaps are ∼4.1 eV. Surprisingly, the carrier density of the conducting phase exceeds 10
cm
and the carrier mobility is only 2.47 cm
V
s
. Contrary to earlier reports, the visible light absorption at 1.8 eV (∼688 nm) is due to the plasmon resonance, arising from the large carrier density. We propose that the hot electron and hole carriers excited via Landau damping (during the plasmon decay) are responsible for the photocatalytic property of this material under visible light irradiation.
Summary
Background
Tinea capitis is still common in developing countries, such as China. Its pathogen spectrum varies across regions and changes over time.
Objectives
This study aimed to clarify the ...current epidemiological characteristics and pathogen spectrum of tinea capitis in China.
Methods
A multicentre, prospective descriptive study involving 29 tertiary hospitals in China was conducted. From August 2019 to July 2020, 611 patients with tinea capitis were enrolled. Data concerning demography, risk factors and fungal tests were collected. When necessary, the pathogens were further identified by morphology or molecular sequencing in the central laboratory.
Results
Among all enrolled patients, 74·1% of the cases were in patients aged 2–8 years. The children with tinea capitis were mainly boys (56·2%) and were more likely than adults to have a history of animal contact (57·4% vs. 35·3%, P = 0·012) and zoophilic dermatophyte infection (73·5% vs. 47%). The adults were mainly female (83%) and were more likely than children to have anthropophilic agent infection (53% vs. 23·9%). The most common pathogen was zoophilic Microsporum canis (354, 65·2%), followed by anthropophilic Trichophyton violaceum (74, 13·6%). In contrast to the eastern, western and northeastern regions, where zoophilic M. canis predominated, anthropophilic T. violaceum predominated in central China (69%, P < 0·001), where the patients had the most tinea at other sites (20%) and dermatophytosis contact (26%) but the least animal contact (39%). Microsporum ferrugineum was the most common anthropophilic agent in the western area, especially in Xinjiang province.
Conclusions
Boys aged approximately 5 years were the most commonly affected group. Dermatologists are advised to pay more attention to the different transmission routes and pathogen spectra in different age groups from different regions.
What is already known about this topic?
Tinea capitis is an infection of the scalp and hair caused by dermatophytes and is still common in developing countries. Prepubertal children are mainly affected.
The pathogen spectrum of tinea capitis varies across different geographical areas and changes over time.
Nationwide prospective epidemiological surveys of tinea capitis in China are rare and out of date.
What does this study add?
This study provides data concerning the epidemiological characteristics and pathogen spectrum of tinea capitis in contemporary China.
Boys aged approximately 5 years were most commonly affected and were more likely than adults to have zoophilic dermatophyte infection.
The main pathogens of tinea capitis in China are zoophilic dermatophytes, mainly Microsporum canis. In contrast to the other regions, the predominant pathogens in central China are anthropophilic dermatophytes.
Plain language summary available online
•Effect of three operating strategies for gas turbine are compared and analyzed.•Two different cooling compensation modes are investigated.•Partial load performance of the combined cooling and power ...system are enhanced.•Daily average energy-saving is promoted by 5.81% for a typical summer day.•Daily average energy-saving is enhanced by 7.20% for a typical winter day.
Frequent partial load operation caused by fluctuating users’ demands is one of the main factors suppressing energy-saving performance of combined cooling and power systems. In order to address this lingering problem, three different operating strategies, namely, inlet guide vanes, inlet air throttling and turbine inlet temperature, are compared and adopted to alter gas turbine characteristic in order to promote the energy-saving performance of the combined cooling and power system under partial loads. The combined cooling and power system consists of a gas turbine coupled to a double-effect absorption chiller. Two insufficient cooling energy compensation modes including self-compensation and grid-compensation are also introduced to further potentially enhance the system’s performance. Key results have revealed that the inlet guide vanes operating strategy is the best option for the system and the self-compensation mode can reap more energy savings for high cooling to power ratio demands under partial load conditions. From the system side perspective, the inlet guide vanes operating strategy is able to improve 4.06% and 4.97% primary energy saving rate respectively compared to the existed inlet air throttling and turbine inlet temperature operating strategies at 50% gas turbine load. Considering the users’ demands, the inlet guide vanes operating strategy incorporating self-compensation mode improves the average primary energy saving rate of 5.81% in the typical summer day and 7.20% in typical winter day in comparison to other existed operating methods.
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