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Anisakid larvae are regarded as an important hazard in marine products, and demand is growing for on-line nondestructive analytical techniques for effective monitoring of these parasites. A UV fluorescent imaging was developed for detection of the third-stage anisakid larvae in marine fishes, and different processing methods were investigated and optimized based on principal component and gray value analyses. Using cod fillets as samples, the efficiency of the developed technique was evaluated, and the overall detection ratio was greater than 80%. These results indicate a promising application of UV fluorescent imaging as an effective and nondestructive technique for identification of anisakid larvae in fishery products. [ABSTRACT FROM AUTHOR]

The ability of DNA to extract fluoroquinolones from model solutions and real probes of food was demonstrated and investigated quantitatively. The interaction between fluoroquinolones and different types of DNA was studied by equilibrium dialysis. The first application of this direct approach allowed us to determine binding constants and binding stoichiometries in different conditions. The binding of enrofloxacin to heat-denatured DNA (d-DNA) from herring sperm is pH- and magnesium-dependent; the highest fraction of bound drugs was found at pH 7 and a magnesium concentration of 0.5–1 mM. Results for three types of DNA: d-DNA, double-stranded DNA and single-stranded DNA were compared. The unwound DNA showed almost doubled binding constants and stoichiometries, thus indicating preferable interaction of enrofloxacin with single-strand regions of DNA. The binding of other fluoroquinolones (lomefloxacin, ciprofloxacin, norfloxacin, danofloxacin and sarafloxacin) with d-DNA is very similar to that of enrofloxacin: the binding constants are in the range from 0.94 × 105 to 2.40 × 105 M−1, and the stoichiometries range from 4.1 to 6.9 fluoroquinolone molecules per 100 DNA bases. The binding properties were quantitatively the same for extraction of fluoroquinolones from model aqueous solutions and from liquid food (milk). The results indicate the efficiency of DNA for selective extraction of fluoroquinolones from real samples for further analysis. This selective binding also allows us to consider DNA as a natural receptor for development of analytical techniques for fluoroquinolones. [ABSTRACT FROM AUTHOR]

Antibody–therapeutic agent conjugates to be delivered directly into the cytosol of tumour cells is required for many target-based therapeutic strategies. For this work, a large non-immune phage-display library was used to select internalizing scFv (single chain variable fragment) directed against EGFR (epidermal growth factor receptor), a tyrosine kinase receptor that is overexpressed in a wide range of tumour cells. The CHO-EGFR-GFP1 (where CHO is Chinese-hamster ovary) cell line, a transfected cell line expressing EGFR–GFP (green fluorescent protein) fusion protein on membranes, and the untransfected cell line CHO-K1 were used as EGFR-positive cells and -negative cells respectively in the subtractive selection procedure. A novel human anti-EGFR scFv (F4-scFv) was isolated. F4-scFv bound native EGFR-bearing cell lines and could be internalized, but did not bind EGFR-negative cell lines. The KD value of F4-scFv was 472 nM as determined on A431 cells. F4-scFv could be used to target therapeutic agents into tumour cells and was expected to be non-immunogenic in humans. Use of a transfected cell line expressing GFP-tagged receptors allows selection and characterization of antibodies to native receptors without the need for protein expression and purification, significantly speeding up the generation of targeting antibodies. [ABSTRACT FROM AUTHOR]

In order to provide an objective and scientific theoretical basis for rational distribution of wheat growth in Yunnan Province, according to the relationship between Yunnan weather conditions and wheat growth adaptability, a study on eco-climate type regionalization of wheat growing areas in Yunnan was conducted using principal component analysis and GIS technology. The results show that Yunnan Province could be divided into four types, namely southern warm and humid wheat growing area, central semi-arid wheat growing area, central semi-humid wheat growing area and north-central cold wheat growing area. [ABSTRACT FROM AUTHOR]

The recently identified anion channel LRRC8 volume-regulated anion channels (VRACs) are heteromeric hexamers constituted with the obligate LRRC8A subunit paired with at least one of the accessory LRRC8B to LRRC8E subunits. In addition to transport chloride, taurine, and glutamate, LRRC8 VRACs also transport the anticancer agent cisplatin and STING agonists 2'3'-cyclic GMP-AMP (cGAMP) and cyclic dinucleotides; hence, they are implicated in a variety of physiological and pathological processes, such as cell swelling, stroke, cancer, and viral infection. Although the subunit composition largely determines VRAC substrate specificity, the opening of various VRAC pores under physiological and pathological settings remains enigmatic. In this study, we demonstrated that VRACs comprising LRRC8A and LRRC8E (LRRC8A/E-containing VRACs), specialized in cGAMP transport, can be opened by a protein component present in serum under resting condition. Serum depletion ablated the tonic activity of LRRC8A/E-containing VRACs, decreasing cGAMP transport in various human and murine cells. Also, heating or proteinase K treatment abolished the ability of serum to activate VRAC. Genetic analyses revealed a crucial role for cGAMP synthase (cGAS) in serum/TNF-promoted VRAC activation. Notably, the presence of cGAS on the plasma membrane, rather than its DNA-binding or enzymatic activity, enabled VRAC activation. Moreover, phospholipid PIP2 seemed to be instrumental in the membrane localization of cGAS and its association with VRACs. Corroborating a role for LRRC8A/D-containing VRACs in cisplatin transport, serum and TNF markedly potentiated cisplatin uptake and killing of cancer cells derived from human or mouse. Together, these observations provide new insights into the complex regulation of VRAC activation and suggest a novel approach to enhance the efficacy of cGAMP and cisplatin in treating infection and cancer. [ABSTRACT FROM AUTHOR]

Context • Since December 2019, medical practitioners discovered a novel coronavirus causing an acute respiratorytract infection in some hospitals in Wuhan, Hubei Province. COVID-19 has spread globally, making it an epidemic worldwide at present. Understanding the mental-health responses of college students to COVID-19 can help a school staff to better guide students seeking education. Objective: • The study aimed to explore the differences between nonmedical and medical college students during the COVID-19 epidemic in their cognitive interest about the disease, preventive behaviors, psychological effects, and job-search intentions, hoping to provide more targeted measures for virus-coping education for college students. Design • The research team conducted a cross-sectional study, using an anonymous online questionnaire. Setting • The study took place at Shanghai, China. Participants • Participants were 1648 college students studying different specialties in various provinces of China, 485 nonmedical students and 1163 medical students. Outcome Measures • The survey’s questions covered the respondents’: (1) general demographic characteristics, (2) cognitive interest and knowledge about COVID-19 and its infectiousness as well as efforts at active learning about infectious diseases and viruses, (3) awareness of precautionary behaviors against COVID-19, (4) effects on mental health, and (5) effects on job-search intentions. The research team used descriptive statistics and Chisquare tests to analyze the survey data. Results • Among nonmedical students: (1) 297 participants (61.2%) were interested in learning about COVID-19, (2) 321 participants (66.2%) took the initiative to learn about the virus, (3) 301 participants (62.1%) took the initiative to learn about infectious disease, and (4) 151 participants (31.1%) watched medical-themed movies or TV series about COVID-19. Among medical students, the corresponding proportions were 772 participants (66.4%), 855 participants (73.5%), 791 participants (68.1%), and 791 participants (68.1%), respectively. Among nonmedical students, 223 participants (46.0%) had N95 masks available, 429 participants (88.5%) had disinfectant supplies available, 271 participants (55.9%) wore goggles in public places, 75 participants (15.5%) chose public transportation, and 77 participants (15.9%) were exposed to public places in the week prior to the survey. Among medical students, the corresponding proportions were 470 participants (40.4%), 935 participants (80.4%), 575 participants (49.4%), 243 participants (20.9%), and 297 participants (25.5%), respectively. Furthermore, COVID-19 had a stronger effect on medical students’ psychology and job-search ambitions. Conclusions • The news about COVID-19 piqued the interest of medical students. Nonmedical students had stronger protective behavior than medical students. The COVID-19 outbreak had a significant influence on medical students’ lives, studies, and moods. In addition, COVID-19 had a greater impact on the job-search intentions of medical students. [ABSTRACT FROM AUTHOR]

Context • In the process of combating the coronavirus disease 2019 (COVID-19) epidemic, medical personnel were at the forefront of the fight. As the future medical workforce, medical students often experienced firsthand how their seniors and teachers had to commit to working hard in combating the epidemic. Many were directly involved in the front line of the fight and that experience could easily have affected their intention to seek employment in a medically related career. Objective • The study intended to evaluate the impact of the COVID-19 pandemic on Chinese medical students’ employment intentions and the factors associated with them to put forward relevant suggestions to provide a basis for medical education in the future. Design • The research team conducted a cross-sectional study, using an anonymous online questionnaire. Setting • The study took place in many provinces and cities in China and was conducted in an online questionnaire. Participants • Participants were 1114 college students studying clinical medicine, college students studying nursing, and students interning during standardized resident training, medical interns. Outcome Measures • The participants completed a self-administered questionnaire, which investigated their psychological statuses related to anxiety and depression as well as COVID-19’s impact on their intentions related to job searches, regarding their willingness to engage in clinical or basic research in epidemic-related specialties and epidemic-related work. Results • Compared to college students studying clinical medicine, the employment intentions of nursing students and medical interns were more vulnerable to the epidemic. Females and nursing students were more reluctant to choose clinical work, and the choice was associated with depression. Nursing college students and medical interns were significantly less willing to engage in infection medicine, respiratory medicine, and intensive care medicine (all P < .001). Medical students with a bachelor’s degree and postgraduate degrees were significantly less willing to engage in infection medicine and respiratory medicine (all P < .001), but medical students from regions with stable epidemics were more willing to engage in intensive care medicine. Medical students with a bachelor’s degree were significantly less likely to be involved in epidemiology-related work than undergraduate students, and students from severe epidemic regions were significantly less willing to work in isolation wards or to go to Wuhan as volunteers. Conclusions • Participants’ psychological statuses related to anxiety and depression, genders, degrees, current educational statuses, and regions affected employment intentions during the epidemic. [ABSTRACT FROM AUTHOR]

Solid phase extraction (SPE) using traditional column materials offers several advantages, but its ability to simultaneously extract and purify commonly used veterinary drugs, such as chloramphenicol, malachite green, leuco-malachite green and semi-carbazone, remains unproven.Therefore, in the present study, a rapid analytical method based on ultrasound-assisted SPE combined with colloidal gold test strips was developed and applied herein to determine the residues of these veterinary drugs in common aquatic products. Under optimized conditions, the method achieved a limit of detection in the range of 0.01-0.5 μg/kg, inter-day RSDs of the spiked samples in the ranges of 0.99-5.58 % and 1.6-7.2 %, and absolute recoveries in the range of 84.2-112.9 % using the colloidal gold immunoassay and enzyme-linked immunosorbent assay methods, respectively. The SPE column efficiently enriched the four veterinary drugs simultaneously, showing considerable potential for determining common veterinary drug residues in aquatic products., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)