[Clinical characteristics of plastic bronchitis and risk factors for recurrence in children]. / å„¿ç«¥å¡‘åž‹æ€§æ”¯æ°”ç®¡ç‚Žä¸´åºŠç‰¹å¾åŠå¤å‘å±é™©å› ç´ åˆ†æž.

OBJECTIVES: To study the clinical characteristics of plastic bronchitis (PB) in children and investigate the the risk factors for recurrence of PB. METHODS: This was a retrospective analysis of medical data of children with PB who were hospitalized in Children's Hospital of Chongqing Medical University from January 2012 to July 2022. The children were divided into a single occurrence of PB group and a recurrent PB group and the risk factors for recurrence of PB were analyzed. RESULTS: A total of 107 children with PB were included, including 61 males (57.0%) and 46 females (43.0%), with a median age of 5.0 years, and 78 cases (72.9%) were over 3 years old. All the children had cough, 96 children (89.7%) had fever, with high fever in 90 children. Seventy-three children (68.2%) had shortness of breath, and 64 children (59.8%) had respiratory failure. Sixty-six children (61.7%) had atelectasis and 52 children (48.6%) had pleural effusion. Forty-seven children (43.9%) had Mycoplasma pneumoniae infection, 28 children (26.2%) had adenovirus infection, and 17 children (15.9%) had influenza virus infection. Seventy-one children (66.4%) had a single occurrence of PB, and 36 cases (33.6%) had recurrent occurrence of PB (≥2 times). Multivariate logistic regression analysis showed that involvement of ≥2 lung lobes (OR=3.376) under bronchoscopy, continued need for invasive ventilation after initial removal of plastic casts (OR=3.275), and concomitant multi-organ dysfunction outside the lungs (OR=2.906) were independent risk factors for recurrent occurrence of PB (P<0.05). CONCLUSIONS: Children with pneumonia accompanied by persistent high fever, shortness of breath, respiratory failure, atelectasis or pleural effusion should be highly suspected with PB. Involvement of ≥2 lung lobes under bronchoscopy, continued need for invasive ventilation after initial removal of plastic casts, and concomitant multi-organ dysfunction outside the lungs may be risk factors for recurrent occurrence of PB.

Functional Effects of a Retained Ancestral Polymorphism in Prestin.

Molecular basis for mammalian echolocation has been receiving much concerns. Recent findings on the parallel evolution of prestin sequences among echolocating bats and toothed whales suggest that adaptations for high-frequency hearing have occurred during the evolution of echolocation. Here, we report that although the species tree for echolocating bats emitting echolocation calls with frequency modulated (FM) sweeps is paraphyletic, prestin exhibits similar functional changes between FM bats. Site-directed mutagenesis shows that the amino acid 308S in FM bats is responsible for the similar functional changes of prestin We strongly support that the occurrence of serine at position 308 is a case of hemiplasy, caused by incomplete lineage sorting of an ancestral polymorphism. Our study not only reveals sophisticated molecular basis of echolocation in bats, but also calls for caution in the inference of molecular convergence in species experiencing rapid radiation.

Growth suppressive effect of pegylated arginase in malignant pleural mesothelioma xenografts.

BACKGROUND: Malignant pleural mesothelioma (MPM) is a difficult-to-treat global disease. Pegylated arginase (BCT-100) has recently shown anti-tumor effects in hepatocellular carcinoma, acute myeloid leukemia and melanoma. This study aims to investigate the effects of PEG-BCT-100 in MPM. METHODS: A panel of 5 mesothelioma cell lines (H28, 211H, H226, H2052 and H2452) was used to study the in vitro effects of BCT-100 by crystal violet staining. The in vivo effects of BCT-100 were studied using 211H and H226 nude mice xenografts. Protein expression (argininosuccinate synthetase, ornithine transcarbamylase, cleaved PARP, cleaved caspase 3, cyclins (A2, D3, E1 and H), CDK4 and Ki67) and arginine concentration were evaluated by Western blot and ELISA respectively. Cellular localization of BCT-100 was detected by immunohistochemistry and immunoflorescence. TUNEL assay was used to identify cellular apoptotic events. RESULTS: Argininosuccinate synthetase was expressed in H28, H226, and H2452 cells as well as 211H and H266 xenografts. Ornithine transcarbamylase was undetectable in all cell lines and xenograft models. BCT-100 reduced in vitro cell viability (IC50 values at 13-24 mU/ml, 72 h) across different cell lines and suppressed tumor growth in both 211H and H226 xenograft models. BCT-100 (60 mg/kg) significantly suppressed tumor growth (p < 0.01) with prolonged median survival (p < 0.01) in both xenograft models. Combining BCT-100 with pemetrexed or cisplatin conferred no additional benefits over single agents. Serum and intratumoral arginine levels were effectively decreased by BCT-100, associated with cytosolic accumulation of BCT-100 within tumor cells. Apoptosis (PARP cleavage in 211H xenografts; Bcl-2 downregulation, and cleavage of PARP and caspase 3 in H226 xenografts; positive TUNEL staining in both) and G1 arrest (downregulation of cyclin A2, D3, E1 and CDK4 in 211H xenografts; suppression of cyclin A2, E1, H and CDK4 in H226 xenografts) were evident with BCT-100 treatment. Furthermore, proliferative factor Ki67 was downregulated in BCT-100 treatments arms. CONCLUSIONS: BCT-100 suppressed tumor growth with prolonged median survival partially mediated by intratumoral arginine depletion resulting in apoptosis and G1 arrest in mesothelioma xenograft models. The findings provide scientific evidence to support further clinical development of BCT-100 in treatment of MPM.

Optical resolution and mechanism using enantioselective cellulose, sodium alginate and hydroxypropyl-ß-cyclodextrin membranes.

Chiral solid membranes of cellulose, sodium alginate, and hydroxypropyl-ß-cyclodextrin were prepared for chiral dialysis separations. After optimizing the membrane material concentrations, the membrane preparation conditions and the feed concentrations, enantiomeric excesses of 89.1%, 42.6%, and 59.1% were obtained for mandelic acid on the cellulose membrane, p-hydroxy phenylglycine on the sodium alginate membrane, and p-hydroxy phenylglycine on the hydroxypropyl-ß-cyclodextrin membrane, respectively. To study the optical resolution mechanism, chiral discrimination by membrane adsorption, solid phase extraction, membrane chromatography, high-pressure liquid chromatography ultrafiltration were performed. All of the experimental results showed that the first adsorbed enantiomer was not the enantiomer that first permeated the membrane. The crystal structures of mandelic acid and p-hydroxy phenylglycine are the racematic compounds. We suggest that the chiral separation mechanism of the solid membrane is "adsorption - association - diffusion," which is able to explain the optical resolution of the enantioselective membrane. This is also the first report in which solid membranes of sodium alginate and hydroxypropyl-ß-cyclodextrin were used in the chiral separation of p-hydroxy phenylglycine.

[Progresses on pharmacological and toxicological effects of Dengzhanxixin injection].

Dengzhanxixin injection is extracted from herbs of Erigeron breviscapusis. Its function includes activate blood, dispel stasis, unblock the collaterals and relieve pain. In clinical, it is widely used for static blood obstruction, wind-stroke and hemiplegia, numbness of limbs, deviated eyes and mouth, dysphasia, chest impediment, heart pain, ischemic stroke, coronary heart disease, and angina pectoris with the pattern mentioned above. In this paper, we planed to review the pharmacological and toxicological effects of Dengzhanxixin injection from relevant studies.

Measurement of polychlorinated biphenyls with hand wipes and matched serum collected from Chinese E-waste dismantling workers: Exposure estimates and implications.

To date, dermal/hand-to-mouth exposure to chemicals in the e-waste recycling environment has not been sufficiently understood, and the importance of dermal absorption of chemicals in e-waste dismantling workers remains controversial. In this study, we utilized hand wipes and matched sera to characterize dermal/hand-to-mouth exposure to PCBs for e-waste dismantling workers, and potential effects on thyroid hormones were also assessed. PCB loadings in hand wipes varied from 0.829-265 ng wipe-1 (11.3-2850 ng m-2 wipe-1), with 37.2 ng wipe-1 (432 ng m-2 wipe-1) as the median value. Serum concentrations of PCBs ranged from 32.3-3410 ng g-1 lipid weight (lw) with 364 ng g-1 lw as the median value. Between wipes and sera, lower-chlorinated congeners (e.g. CB-28, -66, -74, -99,-105 and -118) showed significant associations (p < 0.01), but higher-chlorinated congeners (e.g. CB-138, -153, -156, -170, and -180) did not. These lower-chlorinated CBs were the major contributors to estimated dermal/hand-to-mouth average daily doses (ADDs) and the hazard index (HI). Correspondingly, their estimated contributions to serum levels by dermal absorption were also significant, with the contribution of CB-28 being as high as 21.4%. As a consequence, dermal absorption of some low-chlorinated congeners was a non-negligible route for e-waste dismantling workers. Although insignificant association was shown between serum PCBs and thyroid hormones, the potential health risk should be of concern due to the high levels of PCBs observed in workers' sera.

[Effect of different orthodontic techniques on alveolar bone changes in the upper incisor area of patients with periodontitis].

PURPOSE: To explore the effects of different orthodontic techniques on the changes of alveolar bone density, height and gingival crevicular fluid (GCF) bleeding in upper incisor in patients with periodontitis. METHODS: Twenty-three patients with moderate periodontitis who underwent orthodontic treatment from January 2016 to December 2019 in the Department of Stomatology of Jiangxi Pingxiang People's Hospital were divided into experimentalexperimental group(n=12) and control group(n=11). Patients in the experimental group were treated with bracket-less invisible appliance, while patients in the control group were treated with conventional lip-side fixed appliance. Changes of gingival crevicular hemorrhage index, probing depth, alveolar bone height and bone density in the incisor area were compared between the two groups before and after treatment. Statistical analysis was performed on data using SPSS 22.0 software package. RESULTS: After treatment, the bone mineral density of the upper incisor alveolar crest (L1) of the two groups decreased, and the rate of decrease in the experimental group was significantly less than that in the control group (P<0.05). The bone density at the apical point of the anatomical root of the control group at 1 mm (L3) was also significantly reduced, but there was no significant change in the experimental group. There was no significant change in the alveolar bone height of the upper incisor area between the two groups before and after treatment (P>0.05). Root resorption of the upper incisors in the experimental group was significantly lower than that in the control group(P<0.05). After treatment, the probing depth and GCF bleeding index of the two groups decreased, and the change in the experimental group was significantly greater than that in the control group(P<0.05). CONCLUSIONS: Bracket-free invisible appliance for periodontitis is more conducive to the restoration of alveolar bone mineral density in the upper incisor than the conventional lip-side fixed appliance, and both of which have the same effect on bone height and are safe and effective orthodontic treatment.

Inhibition of ornithine decarboxylase 1 facilitates pegylated arginase treatment in lung adenocarcinoma xenograft models.

Arginine depletion has shown anticancer effects among arginine auxotrophic cancers. An anti­proliferative effect of pegylated arginase (BCT­100) has been shown in acute myeloid leukaemia, hepatocellular carcinoma and mesothelioma. The aim of the present study was to evaluate the effect of BCT­100 in lung adenocarcinoma. A panel of lung adenocarcinoma cell lines and xenograft models were used to investigate the effect of BCT­100. Protein expression, arginine level, putrescine level, spermidine level and apoptosis were analyzed by western blotting, ELISA, high performance liquid chromatography, dot blot and TUNEL assay, respectively. BCT­100 converts arginine to ornithine. BCT­100 reduced in vitro cell viability across different lung adenocarcinoma cell lines and suppressed tumour growth in an HCC4006 xenograft, while paradoxical growth stimulation was observed in H358, HCC827, H1650 and H1975 xenografts. Upon BCT­100 treatment, ornithine decarboxylase 1 (ODC1) was induced in two solid tumour xenografts (H1650 and H1975). It was postulated that the accumulated ornithine could be channeled via ODC1 to produce polyamines that promoted tumour growth. The action of an ODC1 inhibitor (α­difluoromethylornithine, DFMO) was studied in the restoration of the anticancer effects of BCT­100 in lung adenocarcinoma. In both H1650 and H1975 xenografts, a combination of DFMO and BCT­100 significantly suppressed tumour growth, resulting in doubled median survival compared with the control. Putrescine was decreased in almost all treatment arms in the H1650, H1975 and HCC4006 xenografts. Nonetheless spermidine was reduced only following DFMO/BCT­100 treatment in the H1650 and H1975 xenografts. Apoptosis was enhanced in the combined treatment arm in both H1650 and H1975 xenografts. In the HCC4006 xenograft, addition of DFMO did not alter the tumour suppressive effect of BCT­100. In conclusion, inhibition of ODC1 by DFMO was crucial in facilitating BCT­100 treatment in lung adenocarcinoma that was partially mediated by depleting arginine and polyamines with consequent apoptosis.

[Investigation on level and influencing factors of first aid knowledge among dentists in Sichuan province].

OBJECTIVE: The study aims to investigate the cognition degree and influencing factors of first aid knowledge among dentists in Sichuan province, and to provide suggestions for the training of oral clinician. METHODS: A questionnaire was designed for this study. It included the basic situation of population, first aid knowledge level, emergency situation often encountered in stomatology clinic, first aid training situation, learning approach and attitude of first aid knowledge, etc. This questionnaire was used to investigate the dentists of medical institutions in various cities in Sichuan province. The survey results was statistical analyzed. RESULTS: There were 245 valid questionnaires. 1) The level of first aid knowledge of dentists was generally lower in Sichuan province. Work department and other departments work experience were the influencing factors of knowledge level of first aid knowledge among dentists. 2) 87.3% of dentists believed that it was very necessary to master the knowledge of first aid, but in the event of an emergency situation, 73.5% of dentists only can find other doctors to guide themselves to help. 3) The most common way to learn first aid knowledge was through work experience and medical school's first aid course. CONCLUSIONS: Dentists should strengthen the learning and training to improve the first aid skill.

Genome-wide identification and characterization of apple long-chain Acyl-CoA synthetases and expression analysis under different stresses.

Long-chain acyl-CoA synthetases (LACSs) are members of the acyl-activating enzyme superfamily that have important roles in lipid synthesis and storage, fatty acid catabolism, vectorial acylation, and synthesis of cutin and wax. Here, 11 apple MdLACS genes were identified based on the Malus × domestica reference genome, clustered into six groups and mapped to ten chromosomes. Multiple sequence alignment and conserved motifs analyses showed that the sequences of the AtLACS and MdLACS proteins were highly conserved. A cis-element analysis in the promoter regions of the MdLACS genes revealed various elements related to stress responsiveness and plant hormones. Subsequently, expression analysis demonstrated that the MdLACS genes had different expression profiles in different tissues in response to various abiotic stresses. To further study the function of MdLACS genes in apple, MdLACS1 was isolated to identify its basic function, which the function of MdLACS1 in response to apple abiotic stress resistance was determined by the transgenic method. The results showed the MdLACS1 enhanced tolerance to polyethylene glycol, salt, and abscisic acid in the apple callus, suggesting that MdLACS1 is an important regulator in response to abiotic stresses. Finally, the functional interoperability network among the MdLACS proteins was predicted and analyzed, which could the understanding of the possible interactions among proteins and genes regulatory networks concerned with wax biosynthesis and regulatory mechanisms in response to abiotic stresses in apple.

In silico identification of potential inhibitors targeting Streptococcus mutans sortase A.

Dental caries is one of the most common chronic diseases and is caused by acid fermentation of bacteria adhered to the teeth. Streptococcus mutans (S. mutans) utilizes sortase A (SrtA) to anchor surface proteins to the cell wall and forms a biofilm to facilitate its adhesion to the tooth surface. Some plant natural products, especially several flavonoids, are effective inhibitors of SrtA. However, given the limited number of inhibitors and the development of drug resistance, the discovery of new inhibitors is urgent. Here, the high-throughput virtual screening approach was performed to identify new potential inhibitors of S. mutans SrtA. Two libraries were used for screening, and nine compounds that had the lowest scores were chosen for further molecular dynamics simulation, binding free energy analysis and absorption, distribution, metabolism, excretion and toxicity (ADMET) properties analysis. The results revealed that several similar compounds composed of benzofuran, thiadiazole and pyrrole, which exhibited good affinities and appropriate pharmacokinetic parameters, were potential inhibitors to impede the catalysis of SrtA. In addition, the carbonyl of these compounds can have a key role in the inhibition mechanism. These findings can provide a new strategy for microbial infection disease therapy.

[Research progress on wind erosion control with polyacrylamide (PAM).] / èšä¸™çƒ¯é °èƒº(PAM)é˜²æ²»åœŸå£¤é£Žèš€çš„ç ”ç©¶è¿›å±•.

Soil wind erosion is one of the main reasons for soil degradation in the northwest region of China. Polyacrylamide (PAM), as an efficient soil amendment, has gained extensive attention in recent years since it is effective in improving the structure of surface soil due to its special physical and chemical properties. This paper introduced the physical and chemical properties of PAM, reviewed the effects of PAM on soil wind erosion amount and threshold wind velocity, as well as the effect differences of PAM in soil wind erosion control under conditions of various methods and doses. Its effect was proved by comparing with other materials in detail. Furthermore, we analyzed the mecha-nism of wind erosion control with PAM according to its influence on soil physical characteristics. Comprehensive analysis showed that, although some problems existed in wind erosion control with (PAM), PAM as a sand fixation agent, can not only enhance the capacity of the soil resis-tance to wind erosion, but also improve soil physical properties to form better soil conditions. Besides, we proposed that combination of PAM and plant growth would increase the survival rate of plants greatly, control soil wind erosion in wind-erosive areas, and improve the quality of the ecological environment construction. Thus, PAM has practically important significance and wide application prospect in controlling soil wind erosion.

[Distribution, sources and ecological risk assessment of organochlorine pesticides and polychlorinated biphenyl residues in surface sediment from Dahuofang Reservoir, Liaoning].

Twenty-four surface sediment samples collected in Dahuofang Reservoir were analyzed for organochlorine pesticides (OCPs) and polychlorinated biphenyl(PCBs) residues. The results showed that the recent occurrence levels in sediments were 0.70-3.48 ng x g(-1)(with a mean of 1.58 ng x g(-1) +/- 0.71 ng x g(-1) for HCHs, 0.85-4.94 ng x g(-1) (1.94 ng x g(-1) +/- 0.82 ng x g(-1)) for DDTs, 1.46-3.52 ng x g(-1) (2.42 ng x g(-1) +/- 0.64 ng x g(-1)) for PCBs. The inputs of OCPs and PCBs could be attributed to the recent use of relevant products and the heavy historical application which preserved in agricultural soil in adjacent area. Contamination level of OCPs and PCBs in surface sediments decreased from upstream to downstream, and samples of higher contamination level were located in Hunhe river mouth, both of which indicated distribution of OCPs and PCBs in reservoir was influenced by riverine discharge. The ecological risk assessment suggested that the OCPs in the sediments of the study area might pose a bit high harm to the environment, while PCBs might pose little harm to the environment.