Objective To investigate the design of cuffed pediatric tracheal tubes and compare the effects of different tracheal intubation depth placement strategies on the position of the tracheal tube tip and cuff of 5 tracheal tube brands.Methods A total of 180 children who were admitted to Tianjin Children's Hospital from October 2020 to December 2021,with endotracheal intubation under general anesthesia,aged 1-6 years,were enrolled.The length of the subglottic airway was measured by electronic bronchoscopy.Dimensional data from 5 cuffed pediatric tracheal tube brands were recorded,including the length of the tracheal tube cuff,the distance from the tip of the tracheal tube to the upper edge of the cuff,and the tip of the tracheal tube to the lower edge of the tube glottis marker line the distance.Calculation of the required cuffed endotracheal tube internal diameter(ID)for 180 pediatric patients was performed based on the Motoyama formula,the positions of tracheal tube tip and upper cuff border were calculated for each of the 180 tracheas using depth mark to based tracheal tube placement,placement of the tracheal tube tip at 2 cm above the carina,and mid-tracheal tube placement.Results There were differences in the dimensional data of the 5 cuffed pediatric tracheal tube brands.Depth mark-based tracheal tube placement resulted in the incidence rate of tube tip to carina placement less than 1 cm was 3.9%-67.8%,and the highest incidence of bronchial intubation is Ruijing,up to 17.8%.The tracheal tube tip was placed 2 cm above the carina,and no improper placement of the tracheal tube cuff and tube tip was found in all brands.Mid-tracheal tube placement led to 100%subglottic and supraglottic tracheal tube cuff positions,except Weili.Conclusions There are differences in design between different brands of cuffed pediatric tracheal tube,and some of the design deficiencies may lead to the risk of airway complications.The method used to guide the insertion depth and the brand of cuffed tracheal tubes can affect the tracheal tube position.Placement of the tracheal tube tip at 2 cm above the carina allowed safe tracheal tube placement in children aged 1-6 years.

Abstract: Objective To explore the dynamic characteristics of stigmatization in HIV/AIDS patients and provide scientific evidence for psychological care. Methods HIV/AIDS patients receiving antiretroviral therapy (ART) treatment in Nanning Fourth People's Hospital were randomly selected for baseline and 1 year follow-up questionnaire survey including internalized HIV stigma, anticipated HIV stigma, exposure to HIV stigma. The differences between the two groups at different time points were dynamically compared to analyze the changing characteristics of stigma in HIV/AIDS patients. Results After one year of ART treatment, among the eight items of internalizing stigma, five items including the proportion of feeling ashamed of being infected with HIV/AIDS, feeling unclean because of being infected with HIV/AIDS, feeling inferior to others because of having HIV/AIDS, feeling guilty because of having HIV/AIDS, and having a poorer self-perception due to how others view HIV/AIDS decreased significantly from 34.0% to 43.5% at the baseline to 19.5% to 29.5%, showing significant improvement with statistical significance (χ2=18.586, 14.277, 10.473, 12.219, 9.934, P<0.05); among the nine items of anticipated stigma, four items including the proportion of community/community workers not taking my needs seriously, discriminating against me, refusing to provide services for me, and healthcare workers avoiding contact with me decreased significantly from 16.0% to 27.5% at the baseline to 7.0% to 15.5%, respectively, showing significant improvement with statistical significance (χ2=13.690, 15.787, 12.034, 12.593, P<0.05); among the 16 items of exposure to HIV stigma, six items including the proportion of experiencing physical attacks, psychological pressure from spouses/partners, being refused sexual relationships, losing jobs or other economic sources, being rejected or losing a job opportunity due to HIV/AIDS, changing job nature due to HIV/AIDS, or being refused medical services decreased significantly from 2.5% to 15.0% at the baseline to 1.0% to 8.0%, respectively, showing significant improvement with statistical significance (χ2=8.619, 15.558, 6.061, 9.049, 5.432, 8.156, P<0.05). Physical assaults on people with HIV/AIDS increased by 5.5 percent(χ2=5.368, P<0.05). Conclusions Through 1-year dynamic monitoring, 48.48% of the three dimensions of stigma of HIV/AIDS patients were alleviated. Treatment intervention, self-acceptance and the creation of a good non-discriminatory social environment have an important impact on the stigma of HIV/AIDS patients and deserve the attention of society as a whole.

Background: Disrupted circadian rhythms have been associated with the development of irritable bowel syndrome (IBS). In some IBS patients, the symptoms may present with circadian fluctuations. Enterochromaffin cells (EC cells) and tryptophan hydroxylase 1 (TPH1) - 5 - hydroxytryptamine (5 - HT) signaling pathway are currently recognized as the key pathophysiological mechanism of IBS. Aims: To explore whether Bmal1, the core circadian clock gene, is involved in the occurrence of IBS by regulating TPH1-5-HT signaling pathway in EC cells. Methods: Normal Sprague-Dawley (SD) rats and IBS-model SD rats, as well as wild type (WT) and intestine-specific Bmal1 knockout (Bmal1

Objective:Through constructing an online question database of medical physics, teachers and students can make use of the Internet to realize interaction in or after class, so students' ability of independent learning and the quality of teaching can be improved.Methods:Based on teaching outlines, the type, quantity and difficulty of the test questions were discussed and determined by teachers in the teaching and research office, and the online question database of medical physics was constructed with the help of Internet platform to realize self-testing and teacher-student interaction.Results:Through the construction and application of online question database, students' learning initiative was mobilized, the effectiveness of teacher-student interaction was improved, and empirical materials for teaching formation evaluation were obtained. Self-examination and teacher-student interaction help improve students independent learning and problem solving ability. And data generated on the platform enable teachers to know students' learning situation and their teaching quality.Conclusion:The construction and application of Internet + digital online question database of medical physics can greatly promote the teaching effect.

Objective: To evaluate the accuracy of ultrasound-determined end-diastolic velocity (EDV) of central retinal artery (CRA) in diagnosing postoperative low cerebral perfusion pressure (CPP) in the patients with craniocerebral trauma. Methods: Forty-nine patients of both sexes with brain injury, aged 18-64 yr, with body mass index of 18.5-23.9 kg/m², were enrolled.The peak systolic velocity and EDV of CRA were determined using ultrasound at 1 day after operation.Mean arterial pressure and intracranial pressure were recorded, and CPP was calculated (CPP=mean arterial pressure-intracranial pressure). Results: EDV was positively correlated with CPP (r=0.746, P<0.01), and peak systolic velocity was not correlated with CPP (P>0.05). The area under the receiver operating characteristic curve for EDV in diagnosing low CPP was 0.938 (95% confidence interval 0.871-1.000), and the critical value was 3.205 (sensitivity 94.4%, specificity 76.9%). Conclusion Ultrasound-determined EDV of central retinal artery can accurately diagnose postoperative low CPP in the patients with craniocerebral trauma.

Objective: To analyze the physical characteristics of fine particulate matters (PM_2.5) and submicron particulate matters (PM₁), and investigate the factors influencing the emission peak of printer particles. Methods: A 12-hour particle concentration monitoring for PM_2.5 and PM₁ was conducted in a printing shop on January 5^th, 2018. PM_2.5 in the air was analyzed after the monitoring process to figure out morphological characteristics and element composition of printer particles. Besides, experiments were carried out in an enclosed space to detect the number concentration peaks of PM₁ during every printing process. Influencing factors investigated in this study were printer types, toner coverages and interval time between different printing processes. Results: The 12-hour particles concentration monitoring showed that the number concentration of PM₁ and the mass concentration of PM_2.5 were 7.510×10⁴ pt/cm³ and 96.85 μg/m³. The diameter of most PM_2.5 was less than 100 nm, with a fractal dimension of 2.591. Most PM_2.5 appeared as regular spheres with typical agglomeration phenomenon, while some were in rhabditiform or irregular shapes. Element analysis showed that PM_2.5 was mainly composed of C, O, Si, Ca, with less metallic element. The PM₁ emission peak values of three printers were 3.60×10⁴, 3.43×10⁴, 0.31×10⁴ pt/cm³, respectively and the difference was not statistically significant (χ²=5.42, P>0.05). When the page coverage rate was 0%, 2.5%, 5%, 10%, 20% and 50%, the PM₁ emission peak value of printer A was 6.74×10⁴, 4.62×10⁴, 3.82×10⁴, 2.82×10⁴, 1.00×10⁴ and 1.08×10⁴ pt/cm³, and the difference was also not statistically significant (χ²=7.01, P>0.05). The natural logarithm of PM₁ emission peak value in printing work was associated with the resting time before printing and the change value of heating roller temperature (r value was 0.83 and 0.89, respectively, all P values<0.05). Conclusion PM_2.5 and PM₁ in the printing shop stayed at a high level. Particles appeared as various shapes and element compositions were complex. The temperature change of heating roller was one of most important factors that lead to the increased number concentration peak of PM₁.

Objective To evaluate the value of the ratio of optic nerve sheath diameter to eyeball transverse diameter (ONSD/ETD) in assessing intracranial pressure using ultrasound in the patients with brain injury.Methods Forty-six patients of both sexes with brain injury in the surgical intensive care unit,were selected.Craniotomy was performed within 24 h after admission to hospital,and the intracranial pressure probe was placed in the lateral cerebral ventricle of the enrolled patients who were aged 18-80 yr,with Glasgow Coma Scale score 3-15.ONSD and ETD were measured within 3 days after operation,three times a day,and the intracranial pressure was simultaneously recorded.The correlation between ONSD/ETD ratio and intracranial pressure were analyzed using the Pearson correlation analysis.The receiver operating characteristic curve was used to evaluate the accuracy of ONSD/ETD ratio in assessing the intracranial hypertension (intracranial pressure＞20 mmHg).Results The ONSD/ETD ratio was positively correlated with intracranial pressure (r =0.720,P＜0.01).The area under the receiver operating characteristic curve was 0.900 (95％ confidence interval 0.854-0.946),and the threshold was 0.248 (sensitivity 89.4％,specificity 77.5％).Conclusion The ONSD/ETD ratio produces higher accuracy in assessing intracranial pressure in the patients with brain injury.

Objective To study the effect of soluble, refolded, recombinant extracellular domain of the human Fc gamma receptor Ⅱ a (huFcγRⅡa) on the binding of human IgG to cells. Methods Extra-cellular domain of the huFcγRⅡ a gene was amplified from recombinant plasmid pe3huR Ⅱ by PCR and then cloned into pET-28a vector. The recombinant plasmid pETshuR Ⅱ was transformed into E. coli BL21 (DE3) after identified by PCR and doubly digested. The inclusion bodies of fusion protein were extracted and purified by washing, dissolved in 6 mol/L guanidine buffer, and refolded by rapid dilution technique. The refolding protein activity was tested by ELISA and flow cytometry. Results Extraceilular domain of the huFcγRⅡa gene was successfully cloned into pET-28a. The results of SDS-PAGE showed that the molecular mass (Mr) of the expressed protein was 24.8 × 103, and the expression rate was 30%. The purity of recom-binant shuR Ⅱ was up to 90% after washing. ELISA showed that the recombinant shuR Ⅱ was able to bind human IgG in a dose dependent manner, shuRⅡ could competitively inhibit the binding of human IgG to huFcγRⅡa expressed on the surface of COS-7 cells by flow cytometry. Conclusion The results demon-strate that it is possible to obtain large quantities of recombinant shuR Ⅱ which has comparable binding prep-erties to those of the whole membrane bound huFcγR Ⅱ a.

For the purpose of improving the hemodynamics of CABG, the authors presented a new amelioration measurement of symmetric 2-way bypass graft. The physiological blood flow in 1-way and 2-way bypass graft of coronary is simulated with finite element method, and the data on computational hemodynamics of these two cases were compared. The temporal-spatial distributions of hemodynamics during the cardiac cycle such as flow patterns and wall shear stress in the vicinity of anastomosis were analyzed. The study results showed that 2-way bypass graft was of more rational hemodynamics when compared with 1-way bypass graft, and it could improve the flow conditions and decrease the probability of restenosis.
Anastomosis, Surgical ; Blood Flow Velocity ; Coronary Artery Bypass ; methods ; Coronary Circulation ; Humans ; Saphenous Vein ; transplantation