Search

A histidine (His)-tag is composed of six His residues and typically exerts little influence on the structure and solubility of expressed recombinant fusion proteins. Purification methods for recombinant proteins containing His-tags are relatively well-established, thus His-tags are widely used in protein recombination technology. We established a one-step enzyme-linked immunosorbent assay (ELISA) for His-tagged recombinant proteins. We analyzed variable heavy and light chains of the anti-His-tag monoclonal antibody 4C9 and used BLAST analyses to determine variable zones in light (VL) and heavy chains (VH). VH, VL, and alkaline phosphatase (ALP) regions were connected via a linker sequence and ligated into the pGEX-4T-1 expression vector. Different recombinant proteins with His tags were used to evaluate and detect ALP-scFv activity. Antigen and anti-His-scFv-ALP concentrations for direct ELISA were optimized using the checkerboard method. ZIKV-NS1, CHIKV-E2, SCRV-N, and other His-tag fusion proteins demonstrated specific reactions with anti-His-scFv-ALP, which were accurate and reproducible when the antigen concentration was 50 µg mL−1 and the antibody concentration was 6.25 µg mL−1. For competitive ELISA, we observed a good linear relationship when coating concentrations of recombinant human anti-Müllerian hormone (hAMH) were between 0.78 and 12.5 µg mL−1. Our direct ELISA method is simple, rapid, and accurate. The scFv antibody can be purified using a prokaryotic expression system, which provides uniform product quality and reduces variations between batches.

OBJECTIVE: The purpose of this research was to examine the relationship between the hemoglobin-to-red blood cell distribution width ratio (HRR) and cardiovascular disease (CVD)-related mortality in people who have diabetes. METHODS: Data derived from the National Health and Nutrition Examination Survey (NHANES), between the years 1999 to 2018, were meticulously analyzed. Mortality data, encompassing events until December 31, 2019, were systematically collected. A comprehensive group comprising of 8,732 participants were subjected to scrutiny, and subsequently, classified into four distinct groups predicated upon quartiles of baseline HRR levels: Q1 (n = 2,183), Q2 (n = 2,181), Q3 (n = 2,185), and Q4 (n = 2,183). The correlation between HRR and CVD-related mortality was examined through the use of survival curves and Cox proportional hazard regression models, the latter incorporating weights as advised by NHANES. RESULTS: Among the 8,732 participants in the study cohort, CVD-related mortality was identified in 710 cases. The Kaplan-Meier analysis demonstrated a significant association, indicating that a decreased HRR was correlated with a reduction in survival in cases with CVD. Both univariate and multivariable Cox proportional hazard regression analyses consistently indicated that patients exhibiting a lower HRR exhibited a markedly elevated risk of CVD-related mortality in comparison to those with higher HRR. Notably, the correlation between HRR and decreasing CVD-related mortality was discerned to be non-linear. CONCLUSION: In patients with diabetes, a decreased HRR was associated with an increased risk of CVD-related mortality. [ABSTRACT FROM AUTHOR]

This study explores the prognostic value of immune escape-related genes in acute myeloid leukemia (AML) patients. Using TARGET_AML and GSE37642 datasets, we identified CEP55, DNAJC13, and EMC2 as significant prognostic indicators, with high transcript abundance correlating with poor outcomes. Consensus clustering divided patients into two groups, with Cluster 1 showing worse prognosis. A prognostic signature based on these genes stratified patients into high- and low-risk groups, with the high-risk group experiencing worse outcomes. The risk score was an independent prognostic factor. Functional analysis revealed that high-risk genes could promote cell cycle progression. The selected genes were strongly associated with immune cells, particularly mast cells and CD8+ T cells. This study enriches the prognostic evaluation system for AML and suggests a new therapeutic direction. [ABSTRACT FROM AUTHOR]

Influenza virus is one of the main pathogens causing respiratory diseases in humans. Vaccines are the most effective ways to prevent viral diseases. However, the limited protective efficacy of current influenza vaccines highlights the importance of novel, safe, and effective universal influenza vaccines. With the progress of the COVID-19 pandemic, live-attenuated vaccines delivered through respiratory mucosa have shown robustly protective efficacy. How to obtain a safe and effective live-attenuated vaccine has become a major challenge. Herein, using the influenza virus as a model, we have established a strategy to quickly obtain a live-attenuated vaccine by mutating the cleavage site of the influenza virus. This mutated influenza virus can be specifically cleaved by chymotrypsin. It has similar biological characteristics to the original strain in vitro, but the safety is improved by at least 100 times in mice. It can effectively protect against lethal doses of both homologous H1N1 and heterologous H5N1 viruses post mucosal administration, confirming that the vaccine generated by this strategy has good safety and broad-spectrum protective activities. Therefore, this study can provide valuable insights for the development of attenuated vaccines for respiratory viruses or other viruses with cleavage sites. [ABSTRACT FROM AUTHOR]

Acute myeloid leukemia (AML) is a malignant blood cancer with a poor prognosis and complex pathogenesis. Recently, the critical role of circular RNAs (circRNAs) has been demonstrated in the malignant progression of AML. This study aimed to investigate the functional role and underlying mechanism of circ_0001602 in AML development. Quantitative real-time polymerase chain reaction (qRT-PCR) assay was conducted for detecting the expression of circ_0001602, CCND3, microRNA-192-5p (miR-192-5p), and Zinc Finger and BTB Domain-Containing Protein 20 (ZBTB20) mRNA. RNase R assay and Actinomycin D assay were implemented to determine the characteristics of circ_0001602. Cell counting Kit-8 (CCK-8) assay was performed to evaluate cell proliferation. Flow cytometry was employed for assessing cell cycle distribution and apoptosis. Dual-luciferase reporter assay and RIP assay were utilized for confirming the interactions between miR-192-5p and circ_0001602 or ZBTB20. Circ_0001602 and ZBTB20 were upregulated and miR-192-5p level was reduced in AML tissues and cells. Depletion of circ_0001602 repressed cell proliferation and induced cell cycle arrest and apoptosis in AML cells. Functionally, circ_0001602 was identified to be the sponge of miR-192-5p, and miR-192-5p silence restored the suppressive effects of circ_0001602 knockdown on AML cell progression. Furthermore, ZBTB20 was a target of miR-192-5p, and ZBTB20 overexpression neutralized the miR-192-5p-mediated inhibiting actions on the malignant phenotypes of AML cells. Besides, circ_0001602 could sponge miR-192-5p to positively regulate ZBTB20 expression. Circ_0001602 contributed to AML cell development at least partially through modulating the miR-192-5p/ZBTB20 axis, which provided new insights for AML treatment. [ABSTRACT FROM AUTHOR]

Due to the structural complexity and limited controllability of conventional microwave‐absorption materials (MAMs), the precise regulation of atomically‐resolved structures and properties of MAMs remains a significant challenge. The interpretation of the dielectric loss mechanism is usually conduction and polarization losses, while the absence of components‐regulated template materials further hinders the disclosure of the mechanism. Herein, based on the customizable functionality of the MOF platform, a series of pristine bimetallic MOFs with precise and controllable conductivity are successfully constructed through the bimetallic alloying strategy. The controllability is attributed to the alteration of free‐carrier concentration and the subtle difference of interlayer displacement or spacing, both of which originate from the atomic tuning of hetero‐metal. Notably, Cu1.3Ni1.7(HITP)2 features an ultra‐high absorption strength (reflection loss, RL = −71.5 dB) and an ultra‐wide maximum bandwidth (6.16 GHz) at only 15% filling, which ranked in the upper range of all reported MAMs. Due to the metal co‐synergies, Cu1.3Ni1.7(HITP)2 possesses a switchable high absorption peak in a wide range (4–18 GHz). This work opens up an avenue for tailoring the atomic tuning of new MOF‐based electromagnetic wave absorbers and provides a conceptually novel platform. [ABSTRACT FROM AUTHOR]

Objective: Despite strong evidence on the safety and tolerability of the COVID‐19 vaccine, data on vaccination in children with epilepsy, particular younger children with specific epilepsy syndromes, are limited. The protective effects of vaccination against seizure increase upon COVID‐19 infection also remain to be elucidated. Methods: Questionnaire surveys were distributed online via an established WeChat group for patient management as well as in our outpatient clinic. The data collected included demographics and clinical information related to COVID‐19 vaccination and infection. Detailed information related to epilepsy diagnosis and treatment was also collected from our patient database. Logistic regression analysis was performed to determine the factors associated with non‐vaccination. The characteristics of seizures following COVID‐19 infection were described. Results: In total, 354 suitable questionnaires were included in the study. The median age at survey was 6 years (interquartile range 4, 9). The most common epilepsy syndrome was self‐limited epilepsy (n = 153, 43.2%), followed by developmental and/or epileptic encephalopathy (D/EE, n = 81, 22.9%) and genetic generalized epilepsy (n = 59, 16.7%). The vaccine uptake rate was 43.8% (n = 155), and all related side‐effects (n = 11, 7.1%) remitted spontaneously. Younger age (odds ratio [OR] = 0.877, P = 0.001), D/EE (OR = 5.096, P = 0.008), and less than six months seizure‐freedom before vaccination (OR = 3.026, P = 0.005) were associated with unwillingness to be vaccinated. There were no significant differences in the rate of COVID‐19 infection (33.7% vs 32.7%, P = 0.879) and resultant increased seizure activity following infection between the vaccinated and unvaccinated groups after propensity score matching (9.1% vs 15.6%, P = 0.428).Three unvaccinated cases of Dravet syndrome developed status epilepticus following COVID‐19 infection. Significance: Vaccination against COVID‐19 is safe and well tolerated in children, even in younger patients with D/EE. Although the risk of worsening seizures following COVID‐19 infection may not be reduced by immunization, education focused on increased vaccination in pediatric epilepsy is still warranted. [ABSTRACT FROM AUTHOR]

Objective: The phenotype of the chromosomal aberration 47, XXY exhibits considerable heterogenicity. In addition, epilepsy is extremely uncommon in individuals with this chromosomal disorder. As a result, the clinical characteristics of epilepsy in these patients remain poorly understood. Methods: Clinical data and the evolution of epilepsy in a boy diagnosed with chromosomal aberration 47, XXY were collected and analyzed. Furthermore, a systematic literature review was conducted to examine the relationship between chromosomal aberration 47, XXY and epilepsy in children. Results: We identified a novel phenotype associated with the chromosomal anomaly 47, XXY in a 2‐year‐2‐month‐old boy who presented with self‐limited epilepsy with autonomic seizures at onset, followed by developmental and/or epileptic encephalopathy with spike‐wave activation in sleep (D/EE‐SWAS), which was responsive to corticosteroid treatment. Including the present case, we analyzed 21 cases of children diagnosed with epilepsy due to the presence of the 47, XXY chromosomal anomaly. The most common types of epilepsy were focal combined generalized epilepsy (n = 9), epileptic spasms (n = 6), and generalized epilepsy (n = 4). There were six cases of infantile epileptic spasm syndrome (IESS) (n = 5) and developmental and epileptic encephalopathy (n = 1), one case of Lennox–Gastaut syndrome, and one case of D/EE‐SWAS. Apart from corticosteroids in IESS, 15 antiseizure medications (ASMs) were prescribed to eight children in this cohort, with valproate (n = 5) being the most frequently used. Conclusions: The epilepsy types and syndromes associated with the chromosomal anomaly 47, XXY demonstrated considerable heterogeneity. Among the observed phenotypes, IESS and focal epilepsy, which displayed partial responsiveness to multiple ASMs, were the most prevalent. [ABSTRACT FROM AUTHOR]

With the tremendous growth of cloud computing, it is increasingly critical to provide quantifiable performance to tenants and to improve resource utilization for the cloud provider. Though many recent proposals focus on guaranteeing job performance (with a particular note on network bandwidth) in the cloud, they usually lack efficient utilization  of cloud resource, or vice versa. In this paper we present DCloud, which leverages the (soft) deadlines of cloud computing jobs to enable flexible and efficient resource utilization in data centers. With the deadline requirement of a job guaranteed, DCloud employs both time sliding (postponing the launching time of a job) and bandwidth scaling (adjusting the bandwidth associated with VMs) in resource allocation, so as to better match the resource allocated to the job with the cloud's residual resource. Extensive simulations and testbed experiments show that DCloud can accept much more jobs than existing solutions, and significantly increase the cloud provider's revenue with less cost for individual tenants. [ABSTRACT FROM AUTHOR]

The explosive expansion of data center sizes aggravates the power consumption and carbon footprint, which has restricted the sustainable growth of cloud services and seriously troubled data center operators. In recent years, plenty of advanced data center network architectures have been proposed. They usually employ richly-connected topologies and multi-path routing to provide high network capacity. Unfortunately, they also undergo inefficient network energy usage during the traffic valley time. To address the problem, many energy-aware flow scheduling algorithms are proposed recently, primarily considering how to aggregate traffic by flexibly choosing the routing paths, with flows fairly sharing the link bandwidths. In this paper, we leverage software defined network (SDN) technique and explore a new solution to energy-aware flow scheduling, i.e., scheduling flows in the time dimension and using exclusive routing (EXR) for each flow, i.e., a flow always exclusively utilizes the links of its routing path. The key insight is that exclusive occupation of link resources usually results in higher link utilization in high-radix data center networks, since each flow does not need to compete for the link bandwidths with others. When scheduling the flows, EXR leaves flexibility to operators to define the priorities of flows, e.g., based on flow size, flow deadline, etc. Extensive simulations and testbed experiments both show that EXR can effectively save network energy compared with the regular fair-sharing routing (FSR), and significantly reduce the average flow completion time if assigning higher scheduling priorities to smaller flows. [ABSTRACT FROM PUBLISHER]

Rabies virus is a highly neurophilic negative-strand RNA virus with high lethality and remains a huge public health problem in developing countries to date. The double-stranded RNA-binding protein Staufen1 (STAU1) has multiple functions in RNA virus replication, transcription, and translation. However, its function in RABV infection and its mechanism of action are not clear. In this study, we investigated the role of host factor STAU1 in RABV infection of SH-SY-5Y cells. Immunofluorescence, TCID50 titers, confocal microscopy, quantitative real-time PCR and Western blotting were carried out to determine the molecular function and subcellular distribution of STAU1 in these cell lines. Expression of STAU1 in SH-SY-5Y cells was down-regulated by RNA interference or up-regulated by transfection of eukaryotic expression vectors. The results showed that N proficiently colocalized with STAU1 in SH-SY-5Y at 36 h post-infection, and the expression level of STAU1 was also proportional to the time of infection. Down-regulation of STAU1 expression increased the number of Negri body-like structures, enhanced viral replication, and a caused 10-fold increase in viral titers. Meanwhile, N protein and G protein mRNA levels also accumulated gradually with increasing infection time, which implied that STAU1 inhibited rabies virus infection of SH-SY-5Y cells in vitro. In conclusion, our results provide important clues for the detailed replication mechanism of rabies virus and the discovery of therapeutic targets. [ABSTRACT FROM AUTHOR]

Salmonella, a common foodborne pathogen, causes many cases of foodborne illness and poses a threat to public health worldwide. Immunological detection systems can be combined with nanoparticles to develop sensitive and portable detection technologies for timely screening of Salmonella infections. Here, we developed an antibody-probe-based immuno-N-hydroxysuccinimide (NHS) bead (AIB) system to detect Salmonella. After adding the antibody probe, Salmonella accumulated in the samples on the surfaces of the immuno-NHS beads (INBs), forming a sandwich structure (INB–Salmonella–probes). We demonstrated the utility of our AIB diagnostic system for detecting Salmonella in water, milk, and eggs, with a sensitivity of 9 CFU mL−1 in less than 50 min. The AIB diagnostic system exhibits highly specific detection and no cross-reaction with other similar microbial strains. With no specialized equipment or technical requirements, the AIB diagnostic method can be used for visual, rapid, and point-of-care detection of Salmonella. [ABSTRACT FROM AUTHOR]

Zika virus (ZIKV) is an emerging mosquito-transmitted flavivirus that can cause severe disease, including congenital birth defect and Guillain−Barré syndrome during pregnancy. Although, several molecular diagnostic methods have been developed to detect the ZIKV, these methods pose challenges as they cannot detect early viral infection. Furthermore, these methods require the extraction of RNA, which is easy to contaminate. Nonstructural protein 1 (NS1) is an important biomarker for early diagnosis of the virus, and the detection methods associated with the NS1 protein have recently been reported. The aim of this study was to develop a rapid and sensitive detection method for the detection of the ZIKV based on the NS1 protein. The sensitivity of this method is 120 ng mL−1 and it detected the ZIKV in the supernatant and lysates of Vero and BHK cells, as well as the sera of tree shrews infected with the ZIKV. Without the isolation of the virus and the extraction of the RNA, our method can be used as a primary screening test as opposed to other diagnosis methods that detect the ZIKV. [ABSTRACT FROM AUTHOR]