Review of Chemical Sensors for Hydrogen Sulfide Detection in Organisms and Living Cells.

As the third gasotransmitter, hydrogen sulfide (H2S) is involved in a variety of physiological and pathological processes wherein abnormal levels of H2S indicate various diseases. Therefore, an efficient and reliable monitoring of H2S concentration in organisms and living cells is of great significance. Of diverse detection technologies, electrochemical sensors possess the unique advantages of miniaturization, fast detection, and high sensitivity, while the fluorescent and colorimetric ones exhibit exclusive visualization. All these chemical sensors are expected to be leveraged for H2S detection in organisms and living cells, thus offering promising options for wearable devices. In this paper, the chemical sensors used to detect H2S in the last 10 years are reviewed based on the different properties (metal affinity, reducibility, and nucleophilicity) of H2S, simultaneously summarizing the detection materials, methods, linear range, detection limits, selectivity, etc. Meanwhile, the existing problems of such sensors and possible solutions are put forward. This review indicates that these types of chemical sensors competently serve as specific, accurate, highly selective, and sensitive sensor platforms for H2S detection in organisms and living cells.

Design, Synthesis, and Acaricidal/Insecticidal Activities of New Phenylpyrazole Derivatives Comprising an Imide Moiety.

Using nicofluprole as the lead compound, we designed and synthesized a series of new phenylpyrazole analogues through substituting the methyl group on the nitrogen atom of the amide with an acyl group. Bioassay results showed that compounds A12-A17 with a 1-cyanocyclopropimide group exhibited outstanding insecticidal activity. The LC50 values for compounds A12-A17 against Tetranychus cinnabarinus ranged from 0.58 to 0.91 mg/L. Compound A15 showed an LC50 value of 0.29 and 3.10 mg/L against Plutella xylostella and Myzus persicae, respectively. Molecular docking indicated the potential binding interactions of compound A15 with a gamma-aminobutyric acid receptor. Additionally, density functional theory calculations implied that the 1-cyanocyclopropimide structure might be essential for its biological activity. Phenylpyrazole derivatives, containing a 1-cyanocyclopropimide fragment, have the potential for further development as potential insecticides.

Systematic investigation of the Borrelia miyamotoi spirochetes in ticks, wildlife and domestic animal hosts in Yunnan province, Southwest China.

Background: Borrelia miyamotoi is a spirochete species transmitted via hard ticks. Following its discovery in Japan, this pathogen has been detected around the world, and is increasingly confirmed as a human pathogen causing febrile disease, namely relapsing fever. Its presence has been confirmed in the Northeast China. However, there is little information regarding the presence of B. miyamotoi and other hard-tick-borne relapsing fever spirochetes in southern China including Yunnan province, where tick and animal species are abundant and many people both inhabit and visit for recreation. Methods: For the present study, we collected samples of ticks, wildlife, and domestic animal hosts from different counties in Yunnan province. Nucleic acids from samples were extracted, and the presence of B. miyamotoi and other relapsing fever spirochetes was confirmed using polymerase chain reaction (PCR) for the 16S rRNA specific target gene fragment. The positive samples were then amplified for partial genome of the flaB and glpQ genes. Statistical differences in its distribution were analyzed by SPSS 20 software. Sequence of partial 16S rRNA, flaB and glpQ genome were analyzed and phylogenetic trees were constructed. Results: A total of 8260 samples including 2304 ticks, 4120 small mammals and 1836 blood of domestic animal hosts were collected for screening for infection of B. miyamotoi and other relapsing fever spirochetes. Cattle and sheep act as the main hosts and Rhipicephalus microplus, Haemaphysalis nepalensis, H. kolonini and Ixodes ovatus were identified as the important vector host with high prevalence or wide distribution. Only one Mus caroli (mouse) and one Sorex alpinus (shrew) were confirmed positive for relapsing fever spirochetes. Evidence of vertical transmission in ticks was also confirmed. Two known strains of B. miyamotoi and one novel relapsing fever spirochetes, B. theileri-like agent, were confirmed and described with their host adaptation, mutation, and potential risk of spreading and spillover for human beings. Conclusions: Our results provide new evidence of relapsing fever spirochetes in vector and animal hosts in Yunnan province based on large sample sizes, and offer guidance on further investigation, surveillance and monitoring of this pathogen.

Effect of the Kanghuier Transparent Hydrocolloid Dressing in Preventing Central Venous Catheter Infection and Phlebitis after Cardiac Surgery.

Background: As cardiac surgery is complicated, time-consuming, and traumatic, it may cause great damage to the patient's body. Therefore, postoperative indwelling venous catheters are required for hemodynamic monitoring and rapid fluid replenishment. Intravenous catheterization infection can easily lead to phlebitis, which not only affects the success of the operation and patient recovery but may also lead to death in severe cases. Good perioperative care is key to reducing postoperative infection in patients, and the choice of dressings for patients with catheterization plays an important role in reducing catheter infection. Objective: The Kanghuier transparent hydrocolloid dressing is known to effectively prevent and treat wound infections. This study is aimed at exploring whether it can reduce the incidence of postoperative catheter infection and phlebitis in patients undergoing cardiac surgery. Methods: A total of 196 patients undergoing cardiac surgery in the Department of Cardiothoracic Surgery of Zhuhai People's Hospital (Zhuhai Hospital Affiliated with Jinan University) from January 2020 to June 2020 were selected. Among them, 98 patients receiving Kanghuier transparent dressing intervention were selected as group A, and the remaining 98 patients receiving traditional sterile gauze intervention were selected as group B. The incidence of infection and related complications, phlebitis, inflammatory factors, pain at the infusion site, nursing comfort and satisfaction, and quality of life were analyzed and compared between the two groups. Results: It was found that compared with group B, the postoperative central venous catheter infection rate and the incidence of phlebitis were significantly lower in group A. In addition, the inflammatory response of patients in group A was better relieved. Moreover, the nursing comfort and satisfaction and the quality of life of patients in group A were significantly improved. Conclusion: This study suggests that the Kanghuier transparent hydrocolloid dressing is effective in the prevention and treatment of central venous catheter infection and phlebitis in patients after heart surgery.

Review of Electrochemical Biosensors for Food Safety Detection.

Food safety issues are directly related to people's quality of life, so there is a need to develop efficient and reliable food contaminants' detection devices to ensure the safety and quality of food. Electrochemical biosensors have the significant advantages of miniaturization, low cost, high sensitivity, high selectivity, rapid detection, and low detection limits using small amounts of samples, which are expected to enable on-site analysis of food products. In this paper, the latest electrochemical biosensors for the detection of biological contaminants, chemical contaminants, and genetically modified crops are reviewed based on the analytes of interest, electrode materials and modification methods, electrochemical methods, and detection limits. This review shows that electrochemical biosensors are poised to provide miniaturized, specific, selective, fast detection, and high-sensitivity sensor platforms for food safety.