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Conjugation to a carrier protein is essential to give rise to the antigenicity of hapten. Three carrier proteins e.g. KLH (Keyhole Limpet hemocyanin), BSA (bovine serum albumin), and OVA (Ovalbumin) were used mostly. KLH is advantageous to the others, majorly owing to its strong immunogenicity and limited usage in other biological assays. However, the cost of obtaining Keyhole Limpet is high and the solubility of KLH is not as well as the other carriers, especially after hapten conjugation. Here, we extracted the shrimp hemocyanin (SHC) from Litopenaeus vannamei (L. vannamei), which is a commonly sea product worldwide. The high pure SHC could be acquired by two-step purification, with a production yield of > 1 g proteins (98% pure) per 1 kg shrimp. Compared to KLH, the peptide-SHC conjugates exhibit higher solubility after hapten conjugation. Meanwhile, compared with KLH, SHC induces comparable antibody production efficiency in mammals, with or without conjugation. Furthermore, rabbit polyclonal antibodies or mouse monoclonal antibodies were generated by immunizing SHC-peptide conjugates, and the subsequent antibodies were confirmed to be used in western blot, immunofluorescence and immunohistochemistry. Therefore, we demonstrated that SHC may be used as a substitute for KLH in future antibody and vaccine development. [ABSTRACT FROM AUTHOR]

This study presents the validation process of a listening test based on a communicative language test proposed by Bachman (Fundamental considerations in language testing, 1990). It was administered to third-grade high school students by the sixteen Korean Provincial Offices of Education for Curriculum and Evaluation in September 2012 to assess their listening ability at the end of high school learning and compare it with the standard of the CSAT (College Scholastic Ability Test). The research questions were the following. First, to what extent does the test measure the listening comprehension construct? Second, what sub-skills does the test measure? Third, to what extent does the test measure communicative ability? To answer these three questions, a study was designed to examine the test's construct validity using classical test theory (CTT). Then, an exploratory factor analysis (EFA) and a confirmatory factor analysis (CFA) were applied to find a model that would fit the score of 400 examinees to explain the correlation between six divisible sub-skills of English listening comprehension and twenty listening items. R-program is used as a tool to analyze the above data. The results show that this test is not discriminatory, as the purpose of a summative assessment is not to level students into different groups. With an acceptable measurement of the construct, this research concludes that the test does not have a clear division of listening sub-skills but, on the other hand, sufficiently measures communicative ability. [ABSTRACT FROM AUTHOR]

Prostate cancer (PCa) is one of the most common malignant tumors, with a high rate of metastasis and recurrence. Circular RNA_0001165 (circ_0001165) has been shown to be involved in the advance of PCa. However, the interaction between circ_0001165 and microRNA in PCa has not been studied. Quantitative real-time polymerase chain reaction was used to detect the expression of related genes in PCa tissues and cells. The expression of related epithelial-mesenchymal transition proteins was detected by Western blotting. The interaction of miR-654-3p with circ_0001165 or dimethylarginine dimethylaminohydrolase 1 (DDAH1) has been notarized by Dual-luciferase reporter assay and RNA immunoprecipitation assay. Xenotransplantation experiments confirmed the function of circ_0001165 in vivo. Circ_0001165 and DDAH1 are significantly high-expressed in PCa tissues and cells. Silencing circ_0001165 can reduce the proliferation, migration, invasion and tube formation of LNCaP and DU145 cells. MiR-654-3p is a target of circ_0001165. Silencing circ_0001165 can inhibit the malignant behavior of PCa cells by releasing miR-654-3p. In addition, DDAH1 is a target of miR-654-3p. Overexpression of DDAH1 partially restored the inhibitory effect of miR-654-3p on cell proliferation. Animal experiments confirmed the anti-tumor effect of silence circ_0001165 in vivo. Circ_0001165 regulates the expression of DDAH1 by regulating miR-654-3p, thereby mediating the process of PCa, and at least partially promoting the development of PCa cells, providing a novel targeted therapy for PCa. [ABSTRACT FROM AUTHOR]

HIV self-testing (HIVST) increases testing frequency among men who have sex with men (MSM). However, its impact on sexual risk behaviors is unclear. In a randomized controlled trial conducted in Hunan Province, China, HIV-negative MSM were randomized to receive one of two interventions for one year: (1) facility-based HIV testing, or (2) facility-based HIV testing augmented with free HIVST. From April to June 2018, 230 MSM were enrolled. They self-reported sexual behaviors every 3 months for 12 months. Among 216 MSM with follow-ups (intervention: 110; control: 106), adjusting for potential confounders in Generalized Estimating Equation models, there were no statistically significant differences in consistent condom use with male partners (regular/casual) or female partners, nor on number of male or female sexual partners. Provision of free HIVST kits does not increase risky sex and should be included in comprehensive HIV prevention packages, particularly for sexual minority men in China. [ABSTRACT FROM AUTHOR]

This meta-analysis aims to synthesize global evidence on the risk of reinfection among people previously infected with SARS-CoV-2. We systematically searched PubMed, Scopus, Embase and Web of Science as of April 5, 2021. We conducted: (1) meta-analysis of cohort studies containing data sufficient for calculating the incidence rate of SARS-CoV-2 reinfection; (2) systematic review of case reports with confirmed SARS-CoV-2 reinfection cases. The reinfection incidence was pooled by zero-inflated beta distribution. The hazard ratio (HR) between reinfection incidence among previously infected individuals and new infection incidence among infection-naïve individuals was calculated using random-effects models. Of 906 records retrieved and reviewed, 11 studies and 11 case reports were included in the meta-analysis and the systematic review, respectively. The pooled SARS-CoV-2 reinfection incidence rate was 0.70 (standard deviation [SD] 0.33) per 10,000 person-days. The incidence of reinfection was lower than the incidence of new infection (HR = 0.12, 95% confidence interval 0.09–0.17). Our meta-analysis of studies conducted prior to the emergency of the more transmissible Omicron variant showed that people with a prior SARS-CoV-2 infection could be re-infected, and they have a lower risk of infection than those without prior infection. Continuing reviews are needed as the reinfection risk may change due to the rapid evolution of SARS-CoV-2 variants. [ABSTRACT FROM AUTHOR]

Purpose: To compare a novel vacuum suction ureteroscopic laser lithotripsy (VS-URS) with traditional ureteroscopic laser lithotripsy (T-URS) for impacted upper ureteral stones and to better define the potential benefits of VS-URS. Methods: Between May 2019 and March 2021, 158 patients with impacted upper ureteral stones underwent ureteroscopic holmium-YAG laser lithotripsy. Of these, 76 underwent VS-URS and 82 underwent T-URS. In VS-URS procedures, the vacuum suction device is composed of a 5F ureteral catheter and a tee joint. The ureteral catheter is linked to the vacuum aspirator by the sidearm of the tee joint, and a 200 μm fiber is inserted through the tee joint and the ureteral catheter into the stone site for lithotripsy. Results: When compared to the T-URS group, the VS-URS group had a shorter mean operation time (38.18 ± 6.37 min vs. 46.65 ± 5.66 min; P = 0.000), lower fever rate (3.9% vs. 14.6%; P < 0.022), less stone retropulsion (5.3% vs. 18.3%; P = 0.012), lower extra management rate (6.58% vs. 21.95%; P = 0.006), and a higher stone-free rate of the first postoperative day (88.2% vs. 72.0%; P = 0.011). There were no significant differences in stone-free rates 1 month after surgery between groups (94.7% vs. 92.7%; P = 0.748). Conclusions: VS-URS is an effective modality for impacted upper ureteral stones, and has a shorter operating time, lower fever rate, less stone retropulsion, and a higher primary stone-free rate compared with T-URS. [ABSTRACT FROM AUTHOR]

A new scaffold material composed of extracellular matrix (ECM) and thermal sensitive hydrogel (HG), and evaluated its biocompatibility were investigated. We cultured bladder smooth muscle cells with this compound material, and then observed with phase contrast microscopy and scanning electron microscope (SEM) to assess the cell growth and morphology. The cell adhesion and proliferation were detected with MTT assay and cell count. Results show the ECM/HG compounds appeared as a net-like and red-stained construction with enough meshes and without any cellular fragments. 6 h after implantation, cells were observed adhere on the compounds and extend spurious along the fibers 12 h later. Under SEM even some ECM was observed to be secreted. MTT assay shows there was obvious statistic difference among 3 groups ( P<0.05). ECM/HG compound materials show a good biocompatibility, which confirms that it would be an ideal tissue engineering scaffolds. [ABSTRACT FROM AUTHOR]

Audio Video coding Standard (AVS) is the latest audio and video coding standard of China. AVS Part 7 (also known as AVS-M) targets mobility applications where error concealment is of great importance. This paper first briefly introduces the general concept of error concealment. Then two error concealment schemes are proposed and implemented on AVS-M decoder under different test conditions. Simulation results of the schemes and suggestions on how to use these tools are also provided. [ABSTRACT FROM AUTHOR]