Distribution and Drug Resistance of Pathogens in Oral Mucositis Associated with Chemotherapy in Patients with Malignant Hematopathy / 中国实验血液学杂志

OBJECTIVE@#To analyze the distribution and drug resistance of pathogens in oral mucositis associated with chemotherapy in hospitalized patients with malignant hematopathy, so as to provide scientific evidences for rational selection of antibiotics and infection prevention and control.@*METHODS@#From July 2020 to June 2022, 167 patients with malignant hematopathy were treated with chemical drugs in the Department of Hematology, Hainan Hospital, and secretions from oral mucosal infected wounds were collected. VITEK2 COMPECT automatic microbial identification system (BioMerieux, France) and bacterial susceptibility card (BioMerieux) were used for bacterial identification and drug susceptibility tests.@*RESULTS@#A total of 352 strains of pathogens were isolated from 167 patients, among which 220 strains of Gram-positive bacteria, 118 strains of Gram-negative bacteria and 14 strains of fungi, accounted for 62.50%, 33.52% and 3.98%, respectively. The Gram-positive bacteria was mainly Staphylococcus and Streptococcus, while Gram-negative bacteria was mainly Klebsiella and Proteus. The resistance of main Gram-positive bacteria to vancomycin, ciprofloxacin and gentamicin was low, and the resistance to penicillin, cefuroxime, ampicillin, cefotaxime, erythromycin and levofloxacin was high. The main Gram-negative bacteria had low resistance to gentamicin, imipenem and penicillin, but high resistance to levofloxacin, cefotaxime, cefuroxime, ampicillin and vancomycin. The clinical data of oral mucositis patients with oral ulcer (severe) and without oral ulcer (mild) were compared, and it was found that there were statistically significant differences in poor oral hygiene, diabetes, sleep duration less than 8 hours per night between two groups (P<0.05).@*CONCLUSION@#Gram-positive bacteria is the main pathogen of oral mucositis in patients with malignant hematopathy after chemotherapy. It is sensitive to glycopeptide antibiotics and aminoglycosides antibiotics. Poor oral hygiene, diabetes and sleep duration less than 8 hours per night are risk factors for oral mucositis with oral ulcer (severe).

Effects of Blast Wave-induced Biomechanical Changes on Lung Injury in Rats / 生物医学与环境科学（英文）

Objective@#To observe the dynamic impacts of shock waves on the severity of lung injury in rats with different injury distances.@*Methods@#Simulate open-field shock waves; detect the biomechanical effects of explosion sources at distances of 40, 44, and 48 cm from rats; and examine the changes in the gross anatomy of the lungs, lung wet/dry weight ratio, hemoglobin concentration, blood gas analysis, and pathology.@*Results@#Biomechanical parameters such as the overpressure peak and impulse were gradually attenuated with an increase in the injury distance. The lung tissue hemorrhage, edema, oxygenation index, and pathology changed more significantly for the 40 cm group than for the 44 and 48 cm groups. The overpressure peak and impulse were significantly higher for the 40 cm group than for the 44 and 48 cm groups ( < 0.05 or < 0.01). The animal mortality was significantly higher for the 40 cm group than for the other two groups (41.2% . 17.8% and 10.0%, < 0.05). The healing time of injured lung tissues for the 40 cm group was longer than those for the 44 and 48 cm groups.@*Conclusions@#The effects of simulated open-field shock waves on the severity of lung injuries in rats were correlated with the injury distances, the peak overpressure, and the overpressure impulse.

Study of Enhanced Depth Imaging Optical Coherence Tomography in Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a hereditary small artery disease caused by NOTCH3 gene mutation. We performed enhanced depth imaging optical coherence tomography (EDI-OCT) to evaluate the retinal vessel changes in CADASIL patients and assessed their consonance with brain magnetic resonance imaging (MRI) findings.</p><p><b>METHODS</b>Of 27 genetically confirmed patients and an equal number of controls were recruited at the Peking University First Hospital from January 2015 to August 2016. All patients underwent 7T-MRI of the brain. Fazekas score, number of small infarcts and microbleeds were evaluated. All patients and controls underwent EDI-OCT to measure subfoveal choroidal thickness (SFCT), inner and outer diameters as well as arterial and venous wall thickness, and arterial venous ratio of the inner (AVRin) and outer diameters (AVRout). The relation between retinal vessel changes and Fazekas scores, numbers of small infarcts, or microbleeds was analyzed. Paired t-test was used to compare the SFCT and retinal vessel measurement data between patients and controls. Spearman's correlation was used to investigate the correlation between retinal vessel changes and MRI lesions.</p><p><b>RESULTS</b>In CADASIL patients, mean SFCT (268.37 ± 46.50 μm) and mean arterial inner diameter (93.46 ± 9.70 μm) were significantly lower than that in controls (P < 0.001,P = 0.048, respectively). Mean arterial outer diameter (131.74 ± 10.87 μm), venous inner (128.99 ± 13.62 μm) and outer diameter (164.82 ± 14.77 μm), and mean arterial (19.13 ± 1.85 μm) and venous (17.91 ± 2.76 μm) wall thickness were significantly higher than that in controls (P = 0.023,P = 0.004,P < 0.001,P < 0.001, respectively). Arterial inner diameter (rs= -0.39, P= 0.044), AVRin (rs= -0.65,P < 0.001), and AVRout (rs= -0.56, P= 0.002) showed a negative correlation with the number of small infarcts. Venous inner diameter (rs = 0.46, P= 0.016) showed a positive correlation with the number of small infarcts. Venous inner diameter (rs = 0.59, P= 0.002), outer diameter (rs = 0.47, P= 0.017), showed a positive correlation with the number of cerebral microbleeds (CMBs). AVRin (rs= -0.52, P= 0.007) and AVRout (rs= -0.40, P= 0.048) showed a negative correlation with the number of CMBs.</p><p><b>CONCLUSIONS</b>Measurement of retinal vessels using EDI-OCT correlates moderately well with MRI parameters. EDI-OCT might be a useful evaluation tool for CADASIL patients.</p>