[Epidemiology of high myopia among children and adolescents in China].

Myopia, especially high myopia, seriously affects the children and adolescents' quality of learning and life relating to a series of eye diseases. More and more studies show that the prevalence of high myopia in children and adolescents in China continues to rise, and gradually increases with age, showing a trend of younger age development. In this review, the existing literature was systematically reviewed to explore the differences in the prevalence of high myopia among people at different times, ages, and regions and understand the epidemiological status of high myopia in children and adolescents, so as to provide theoretical basis for further prevention and control of high myopia.

[Prenatal pyrethroid pesticides exposure and neurodevelopment of 2-year-old children: a birth cohort study].

Objective: To investigate the influence and critical windows of prenatal exposure to pyrethroid pesticides (PYRs) on neurodevelopment of 2-year-old children. Methods: The subjects of this study were derived from the Xuanwei Birth Cohort. A total of 482 pregnant women who participated in the rural district of Xuanwei birth cohort from January 2016 to December 2018 were included. Maternal urinary concentrations of PYRs metabolites during 8-12 gestational weeks, 20-23 gestational weeks and 32-35 gestational weeks were measured with ultra high performance liquid chromatography system coupled with a tandem mass spectrometry detector. Child neurodevelopment was evaluated with the Bayley Scales of Infant and Toddler Development-Third Edition at 2 years of age. Multivariate linear regression models and binary logistic regression models were used to assess the association between PYRs exposure during pregnancy and children's neurodevelopment. Results: A total of 360 mother-child pairs had complete data on maternal urinary PYRs metabolites detection and children's neurodevelopment assessment. The detection rate of any one PYRs metabolites during the first, second and third trimester were 93.6% (337/360), 90.8% (327/360) and 94.2% (339/360), respectively. The neurodevelopmental scores of Cognitive, Language, Motor, Social-Emotional, and Adaptive Behavior of 2-year-old children were (102.3±18.9), (100.2±16.3), (102.0±20.3), (107.8±23.3) and (85.8±18.6) points, respectively. After controlling for confounding factors, 4-fluoro-3-phenoxybenzoic acid (4F3PBA, one of PYRs metabolites) exposure in the first trimester reduced Motor (ß=-5.02, 95%CI: -9.08, -0.97) and Adaptive Behavior (ß=-4.12, 95%CI:-7.92, -0.32) scores of 2-year-old children, and increased risk of developmental delay of adaptive behavior (OR=2.07, 95%CI:1.13-3.82). Conclusion: PYRs exposure during the first trimester of pregnancy may affect neurodevelopment of 2-year-old children, and the first trimester may be the critical window.

[Implement of mixed reality navigation based on multimodal imaging in the resection of intracranial eloquent lesions].

Objective: To examine the clinical feasibility of mixed reality navigation (MRN) technology based on multimodal imaging for the resection of intracranial eloquent lesions. Methods: Fifteen patients with intracranial eloquent lesions admitted to the Department of Neurosurgery, the First Medical Center, People's Liberation Army General Hospital from September 2020 to September 2021 were retrospectively enrolled. There were 7 males and 8 females, aged (50±16) years (range: 16 to 70 years). Postoperative pathological diagnosis included meningioma (n=7), metastatic carcinoma (n=3), cavernous hemangioma, glioma, ependymoma, aneurysmal changes and lymphoma (n=1, respectively). The open-source software was used to perform the three-dimensional visualization of preoperative images, and the self-developed MRN system was used to perform the fusion and interaction of multimodal images, so as to formulate the surgical plan and avoid damaging the eloquent white matter fiber tracts. Traditional navigation, intraoperative ultrasound and fluorescein sodium angiography were used to determine the extent of lesion resection. The intraoperative conditions of MRN-assisted surgery were analyzed, and the setup time and localization error of MRN system were measured. The changes of postoperative neurological function were recorded. Results: MRN based on multimodal imaging was achieved in all patients. The MRN system setup time (M(IQR)) was 36 (12) minutes (range: 20 to 44 minutes), and the localization error was 3.2 (2.0) mm (range: 2.6 to 6.7 mm). The reliability of eloquent white matter fiber tracts localization based on MRN was rated as "excellent" in 11 cases, "medium" in 3 cases, and "poor" in 1 case. There were no perioperative death and no new impairment in motor, language, or visual functions after operation. Transient limb numbness occurred in 1 patient after operation, and recovered to the preoperative state in 2 weeks after operation. Conclusion: The MRN system based on multimodal imaging can improve the surgical accuracy and safety, and reduce the incidence of iatrogenic neurological dysfunction.

[Biological characteristics and genomic information of a bacteriophage against pan-drug resistant Klebsiella pneumoniae in a burn patient and its effects on bacterial biofilm].

Objective: To isolate a bacteriophage against pan-drug resistant Klebsiella pneumoniae in a burn patient, and to study its biological characteristics, genomic information, and effects on bacterial biofilm. Methods: (1) In 2018, pan-drug resistant Klebsiella pneumoniae UA168 (hereinafter referred to as the host bacteria) solution isolated from the blood of a burn patient in Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine (hereinafter referred to as Ruijin Hospital) was used to isolate and purify the bacteriophage against pan-drug resistant Klebsiella pneumoniae from the sewage of Ruijin Hospital with sewage co-culture method, drip plate method, and double-agar plate method. The bacteriophage was named as phage KP168 and the plaque morphology was observed. (2) The phage KP168 solution was taken for cesium chloride density gradient centrifugation and dialysis, and then the morphology of phage KP168 was observed through transmission electron microscope after phosphotungstic acid negative staining. (3) The phage KP168 solution was taken to determine the lytic ability of the phage KP168 against 20 strains of pan-drug resistant Klebsiella pneumoniae isolated from the burned patients' blood in Ruijin Hospital by the drip plate method, and then the lysis rate was calculated. (4) The phage KP168 solution at a initial titer of 9.3×10(11) plaque-forming unit (PFU)/mL (400 µL per tube) and the host bacteria solution at a concentration of 1×10(9) colony-forming unit (CFU)/mL (4 mL per tube) were conventionally shaking cultured together for 4 hours at multiplicity of infection (MOI) of 10.000, 1.000, 0.100, 0.010, or 0.001, respectively (1 tube per MOI). The titer of phage KP168 was measured by the double-agar plate method (the measurement method was the same below) to select the optimal MOI. The experiment was repeated three times. (5) The host bacteria solution at a concentration of 1×10(9) CFU/mL (4 mL per tube) and the phage KP168 solution at an adjusted titer of 5×10(7) PFU/mL (400 µL per tube) were mixed at the MOI of 0.005. The plaques were counted 0 (immediately), 1, 2, 3, 4, 5, 15, and 30 minutes (1 tube at each time point) after mixing by the double-agar plate method (the counting method was the same below), and the percentage of adsorbed phages was calculated to screen for the optimal adsorption time. The experiment was repeated three times. (6) The host bacteria solution at a concentration of 1×10(9) CFU/mL (300 µL per tube) and the phage KP168 solution at a titer of 5×10(8) PFU/mL (60 µL per tube) were mixed at MOI of 0.005 and conventionally shaking cultured after standing for the optimal adsorption time. The phage KP168 titer was measured 0 (immediately), 10, 20, 30, 40, 50, 60, 70, 80, 90, and 100 minutes after culture, and a one-step growth curve was drawn. The experiment was repeated three times. (7) The phage KP168 solution at a titer of 2.5×10(10) PFU/mL was left to stand for 1 hour at 37, 40, 50, 60, or 70 ℃ (3 tubes at each time point, 1 mL per tube) for counting the plaques, and then the thermal stability curve was drawn. SM buffer at a pH values of 5.0, 6.0, 7.0, 7.4, 8.0, 9.0, or 10.0 were added to the phage KP168 solution at a titer of 3.0×10(10) PFU/mL, respectively. The mixed solution was left to stand for 1 hour at 37 ℃ (3 tubes of each pH, each tube containing 100 µL phage KP168 solution and 900 µL SM buffer), and then the plaques were counted, and an acid-base stability curve was drawn. (8) The phage KP168 solution was taken for DNA extraction and sequencing after dialysis as in experiment (2). The whole genome was annotated with Prokka to obtain the coding sequence of phage KP168. Nucleotide's BLAST function was used to proceed nucleic acid sequence alignment for finding a known phage with the highest similarity to the phage KP168 nucleic acid sequence, and Blastx function was used to translate the coding sequence into protein for its function prediction. The comparison with Antibiotic Resistance Genes Database and Virulence Factors Database was proceeded. (9) In a 96-well plate, at a MOI of 1.000, 0.100, 0.010 or 0.001 (3 wells per MOI), 20 µL phage KP168 solution at a initial titer of 5.8×10(10) PFU/mL was added to 200 µL host bacteria solution at a concentration of 1.5×10(8) CFU/mL (the same concentration below) for co-cultivation for 48 hours. After 200 µL host bacteria solution was left to stand for 48 hours, 20 µL phage KP168 solution at a titer of 1×10(6,) 1×10(7,) 1×10(8,) 1×10(9,) or 1×10(10) PFU/mL (3 wells per titer) was added respectively for action for 4 hours. In both experiments, 200 µL host bacteria solution added with 20 µL SM buffer (3 wells) acted as a negative control, and 220 µL LB culture medium (3 wells) acted as a blank control. Absorbance values were measured by a microplate reader, and inhibition/destruction rates of biofilm were calculated. The experiments were both repeated three times. Results: (1) The plaques of phage KP168 successfully isolated and purified were transparent and round, and its diameter was approximately 1.5 mm. (2) The phage KP168 has a regular polyhedron structure with a diameter of about 50 nm and without a tail. (3) The phage KP168 could lyse 13 of 20 strains of Klebsiella pneumoniae from burned patients, with a lysis rate of 65.0%. (4) When MOI was 1.000, the titer was the highest after co-culturing the phage KP168 with the host bacteria for 4 hours, which was the optimal MOI. (5) After the mixing of the phage KP168 with the host bacteria for 4 minutes, the percentage of the adsorbed phage reached the highest, which was the optimal adsorption time. (6) The one-step growth curve showed that during the lysis of the host bacteria by phage KP168, the incubation period was about 10 minutes, and the lysis period was about 40 minutes. (7) With the condition of 40 ℃ or pH 7.4, the number of plaques and the activity of phage KP168 reached the highest. (8) The genome of phage KP168 was a linear double-stranded DNA with a length of 40 114 bp. There were 48 possible coding sequences. It had the highest similarity to Klebsiella phage_vB_Kp1. The most similar known proteins corresponding to the translated proteins of coding sequences contained 23 hypothetical proteins and 25 proteins with known functions. No resistance genes or virulence factor genes were found. The GeneBank accession number was KT367885. (9) After 48 hours of co-cultivation of the phage KP168 and the host bacteria at each MOI, the inhibition rates of biofilm were similar, with an average of about 45%. After the phage KP168 with a titer of 1×10(9) PFU/mL acted on the biofilm formed by the host bacteria for 4 h, the destruction rate of biofilm was the highest, reaching an average of 42%. Conclusions: In this study, a bacteriophage against pan-drug resistant Klebsiella pneumoniae from a burn patient, phage KP168, is isolated from sewage, which belongs to the tailless phage. It has a wide host spectrum, short adsorption time, and short incubation period, with certain thermal and acid-base stability. Its genomic information is clear, and it does not contain resistance genes or virulence factor genes. It also has an inhibitory effect on the formation of bacterial biofilm and a destructive effect on the formed bacterial biofilm.

5-Aminolevulinic acid ameliorates cadmium-induced morphological, biochemical, and ultrastructural changes in seedlings of oilseed rape.

Due to its prolific growth, oilseed rape (Brassica napus L.) can be grown successfully for phytoremediation of cadmium (Cd)-contaminated soils. Nowadays, use of plant growth regulators against heavy metals stress is one of the major objectives of researchers. The present study evaluates the ameliorate effects of 5-aminolevulinic acid (ALA, 0, 0.4, 2, and 10 mg/l) on the growth of oilseed rape (B. napus L. cv. ZS 758) seedlings under Cd stress (0, 100, and 500 µM). Results have shown that Cd stress hampered the seedling growth by decreasing the radical and hypocotyls length, shoot and root biomass, chlorophyll content, and antioxidants enzymes. On the other hand, Cd stress increased the level of malondialdehyde (MDA) and production of H2O2 and accumulation of Cd in the shoots. The microscopic study of leaf mesophyll cells showed that toxicity of Cd totally destroyed the whole cell structure, and accumulation of Cd also appeared in micrographs. Application of ALA at lower dosage (2 mg/l) enhanced the seedling growth and biomass. The results showed that 2 mg/l ALA significantly improved chlorophyll content under Cd stress and decreased the level of Cd contents in shoots. Application of ALA reduced the MDA and H2O2 levels in the cotyledons. The antioxidants enzymes (ascorbate peroxidase, peroxidase, catalase, glutathione reductase, and superoxide dismutase) enhanced their activities significantly with the application of 2 mg/l ALA under Cd stress. This study also indicated that higher dosage of ALA (10 mg/l) imposed the negative effect on the growth of oilseed rape. Microscopic study showed that application of ALA alleviated the toxic effects of Cd in the mesophyll cell and improved the cell structure. Use of 2 mg/l ALA under 500 µM Cd was found to be more effective, and under this dosage, cell structure was clear, with obvious cell wall and cell membrane as well as a big nucleus, which was found with well-developed two or more nucleoli. Chloroplast was almost round in shape and contained thylakoids membranes and grana, but starch grains were not found in chloroplast comparatively to other treatments. On the basis of our results, we can conclude that ALA has a promotive effect which could improve plant survival under Cd stress.