Objective To detect serum levels of 25 ? hydroxyvitamin D (25 [OH] D) and matrix metalloproteinase 9(MMP?9)in patients with chronic spontaneous urticaria(CSU), and to explore their significance. Methods Totally, 56 patients with CSU and 25 healthy controls were enrolled into this study. High?performance liquid chromatography tandem?mass spectrometry(LC?MS/MS)and enzyme?linked immunosorbent assay(ELISA) were performed to measure serum levels of 25(OH)D and MMP?9 respectively in these subjects. Statistical analysis was carried out by two independent samples t?test or Wilcoxon rank sum test for comparisons of the above indexes between the two groups, and by Spearman rank correlation analysis for assessment of relationships between the serum levels of 25(OH)D and MMP?9 as well as between the two indexes and disease severity. Results Of the 56 patients, 19 were diagnosed with mild CSU, 26 with moderate CSU and 11 with severe CSU. Compared with the control group, the patient group showed significantly lower serum levels of 25(OH)D(21.74 ± 6.04 vs. 30.17 ± 2.21μg/L, P<0.05), but significantly higher serum levels of MMP?9(Median[P25-P75]:291.55[166.18-594.46]vs. 138.46[94.27-233.12]μg/L, P<0.05). In the patient group, the serum level of 25(OH)D was negatively correlated with that of MMP?9 (rs=-0.26, P<0.05), but uncorrelated with the severity of CSU(rs=-0.20, P>0.05);the serum level of MMP?9 was positively correlated with the severity of CSU(rs=0.27, P<0.05). Conclusion Vitamin D and MMP?9 may play a role in the occurrence of CSU.

Objective To investigate the clinical effects and indications of phacoemulsification and soft intraocular lens(IOL)implantation combined with viscogoniosynechialysis in the management of primary angle closure glaucoma(PACG).Methods Forty-six eyes of primary angle closure glaucoma with co-existing cataract were treated with phacoemulsification and IOL implantation combined with goniosynechialysis.The mean follow-up duration was 9 to 24 months.The main outcome measures were pre-operative and post-operative changes of intraocular pressure,visual acuity,depth of anterior chamber,anterior chamber angle,outflow facility of aqueous humor(C values)and PO/C ratio,and the number of glaucoma eye drops required.Results Compared with pre-operation,intraocular pressure was decreased(paired t test,P

Objective To investigate the relationship between negative acute phase proteins and chronic urticaria (CU).Methods Fifty patients with CU were enrolled into this study,and divided into three grades,i.e.,mild (grade 1),moderate (grade 2) and severe (grade 3) according to symptoms.Twenty-eight health checkup examinees served as the control group.Immunoturbidimetry was performed to determine serum levels of prealbumin (PA) and transferrin (TRF).Enzyme-linked immunosorbent assay was conducted to measure serum levels of insulinlike growth factor-1 (IGF-1) and tumor necrosis factor-α (TNF-α).Statistical analysis was carried out to assess differences in these indices between these two groups,the relationship among these indices and between these indices and disease severity.Results Compared with the control group,the patients with CU showed reduced serum levels of PA ((229.99 ± 54.16) vs.(272.06 ± 36.42) mg/L,t =3.667,P ＜ 0.05) and IGF-1 ((177.23 ± 46.48) vs.(239.88 ± 45.16) μg/L,t =5.748,P＜ 0.05),but higher serum levels of TNF-α ((25.39 ± 11.01) vs.(14.13 ± 6.12) ng/L,t =4.989,P＜ 0.05),and similar serum levels of TRF ((2.48 ± 0.49) vs.(2.48 ± 0.25) g/L,P＞ 0.05).The serum level of PA showed a significant negative correlation with that of TNF-α (r =-0.312,P ＜ 0.05),as well as with disease severity (r =-0.635,P ＜ 0.01),whereas the serum level of TNF-α showed a significant positive correlation with disease severity (r =0.409,P ＜ 0.01),and no statistical correlation was found between the remaining indices (all P ＞ 0.05) in the patients with CU.Conclusions Serum levels of some negative acute phase proteins decrease and negatively correlate with disease severity in patients with CU.Acute phase response may be involved in the occurrence of CU.

Objective To evaluate the relationship of acute-phase response and coagulation/fibrinolysis with chronic urticaria (CU).Methods Fifty-three patients with CU and twenty-five healthy human controls were enrolled in this study.Venous blood samples were collected from all of these subjects.Then,enzyme-linked immunosorbent assay was carried out to measure the serum levels of interleukin-6 (IL-6) and amyloid protein A (AA),and immunoturbidimetry to determine the levels of serum high sensitive C-reactive protein (Hs-CRP) and plasma D-dimer.The patients with CU were classified into three groups according to the severity of clinical symptoms.The levels of serum IL-6 and plasma D-dimer were given in mean ± standard deviation,and those of serum AA and Hs-CRP in mean (25th percentile,75th percentile).Rank sum test and t test were performed to compare these parameters between the patients and controls,and Spearman rank correlation analysis was conducted to study the relationship among these parameters as well as between these parameters and symptom severity in these patients.Results The levels of serum IL-6,serum AA and plasma D-dimer were (10.70 ± 4.94) ng/L,4.92 (8.22,12.51) μg/L,and (222.32 ± 163.69) μg/L respectively in the patients with CU,significantly higher than those in the healthy controls ((7.49 ± 3.41) ng/L,2.11 (1.21,2.83) μg/L,(104.72 ± 43.12) μg/L,respectively,all P＜ 0.05),while no significant differences were observed between the patients and controls in the level of serum HsCRP (0.30 (0.10,1.40) mg/L vs.0.30 (0.10,0.55) mg/L,P ＞ 0.05).In patients with CU,the levels of serum IL-6 were unrelated to those of serum Hs-CRP,serum AA,or plasma D-dimer (all P ＞ 0.05),whereas a positive correlation was observed between the levels of serum Hs-CRP and AA (r =0.67,P ＜ 0.01),serum Hs-CRP and plasma D-dimer (r =0.49,P ＜ 0.01),serum AA and plasma D-dimer (r =0.38,P ＜ 0.01).Further more,the levels of serum Hs-CRP,AA and plasma D-dimer were significantly correlated with symptom severity in patients with CU (r =0.63,0.62,0.47,respectively,all P ＜ 0.01).Conclusions Acute-phase response coexists with the activation of coagulation system in patients with CU,suggesting a potential association between acute-phase response and coagulation system activation.

Objective To measure the expressions of programmed death?1(PD?1)and programmed death ligand?1(PD?L1)on peripheral blood T lymphocytes of patients with condyloma acuminatum(CA), and to investigate their role in cellular immunity in these patients. Methods Peripheral blood samples were obtained from 30 patients with CA(CA group)and 20 healthy human controls (control group). Flow cytometry was conducted to detect the expressions of PD?1 and PD?L1 on the surfaces of peripheral blood CD4+and CD8+T lymphocytes, and to determine the counts of CD4+and CD8+T lymphocytes. Enzyme?linked immunosorbent assay(ELISA)was performed to measure the levels of serum interleukin?2(IL?2)and interferon?γ(IFN?γ). Statistical analyses were carried out to compare the above parameters between the two groups, and to assess the relationship of PD?1 and PD?L1 expressions with the counts of CD4+and CD8+T lymphocytes as well as with the serum levels of IL?2 and IFN?γ. Results There was a significant increase in the expression rates of PD?1 and PD?L1 on CD4+T lymphocytes(PD?1:9.48%± 3.31%vs. 7.12%± 2.16%, t=2.81, P<0.01;PD?L1:4.40%± 1.46%vs. 3.26%± 1.13%, t=3.16, P<0.01)and CD8+T lymphocytes(PD?1:12.52%± 3.17%vs. 9.95%± 2.17%, t=3.16, P<0.01;PD?L1:7.07%± 2.23%vs. 5.39%± 1.69%, t=2.88, P<0.01)in the CA group compared with the control group. Moreover, the CA group showed significantly lower counts of CD4+T lymphocytes(727.43 ± 138.59/μl vs. 804.25 ± 92.83/μl, t=2.17, P<0.05)and CD4/CD8 ratio(1.23±0.35 vs. 1.46 ± 0.34, t = 2.24, P < 0.05) than the control group, while no significant difference was observed in CD8 + T lymphocyte counts between the CA group and control group(613.60 ± 121.60/μl vs. 572.45 ± 103.08/μl, t=1.24, P>0.05). The levels of serum IL?2 and IFN?γwere both lower in the CA group than in the control group(t=2.12, 2.16, respectively, both P < 0.05). In the CA group, PD?1 and PD?L1 expression levels on peripheral blood CD4 + T lymphocytes were both negatively correlated with CD4+T lymphocyte counts, the CD4/CD8 ratio, as well as IL?2 and IFN?γserum levels(all P<0.05), and those on peripheral blood CD8+T lymphocytes were also negatively correlated with the CD4/CD8 ratio(all P<0.05), but uncorrelated with CD8+T lymphocyte counts(both P>0.05). Conclusion PD?1 was highly expressed on peripheral blood T lymphocytes from patients with CA, which may inhibit T lymphocyte?mediated immune response, decrease CD4+T lymphocyte counts, the CD4/CD8 ratio as well as IL?2 and IFN?γserum levels by interacting with its ligand PD?L1 and forming the PD?1/PD?L1 signaling pathway.

OBJECTIVETo study the biomechanical mechanism of head injuries beaten with sticks, which is common in the battery or assaultive cases.

METHODSIn this study, the Hybrid-III anthropomorphic test device and finite element model (FEM) of the total human model for safety (THUMS) head were used to determine the biomechanical response of head while being beaten with different sticks. Total eight Hybrid-III tests and four finite element simulations were conducted. The contact force, resultant acceleration of head center of gravity, intracranial pressure and von Mises stress were calculated to determine the different biomechanical behavior of head with beaten by different sticks.

RESULTSIn Hybrid-III tests, the stick in each group demonstrated the similar kinematic behavior under the same loading condition. The peak values of the resultant acceleration for thick iron stick group, thin iron stick group, thick wooden stick group and thin wooden stick group were 203.4 g, 221.1 g, 170.5 g and 122.2 g respectively. In finite element simulations, positive intracranial pressure was initially observed in the frontal comparing with negative intracranial pressure in the contra-coup site. Subsequently the intracranial pressure in the coup site was decreasing toward negative value while the contra-coup intracranial pressure increasing toward positive values.

CONCLUSIONSThe results illustrated that the stiffer and larger the stick was, the higher the von Mises stress, contact force and intracranial pressure were. We believed that the results in the Hybrid-III tests and THUMS head simulations for brain injury beaten with sticks could be reliable and useful for better understanding the injury mechanism.

Objective:To explore the application effect of a new type of simulated dermatologic surgical mold based on 3D printing in standardized residency training of dermatology.Methods:In this study, 35 residents in Department of Dermatology, The Second Affiliated Hospital of Guangzhou Medical University from January 2018 to May 2019 were randomly divided into two groups: a new mold group based on 3D printing ( n=18) and a traditional mold group ( n=17). Two groups of residents were examined by dermatologic biopsy on the mold, and the effect of teaching was evaluated by questionnaire survey. SPSS 22.0 was used for data analysis, and the measurement data was expressed by (means ± standard deviation). The comparison between the new mold group and the traditional mold group was made by two independent samples t test. Results:The scores of dermatologic biopsy examination of residents in the new mold group were higher than those in the traditional mold group, and the differences were statistically significant ( P<0.01); and the scores of the questionnaires for the teaching effect of the new mold group were higher than those of the traditional mold group, and the differences were statistically significant ( P<0.01). Conclusion:The new type of simulated dermatologic surgical mold based on 3D printing, which has been successfully applied in the practical training of residents, lays a solid foundation for the actual clinical operation and significantly improves the teaching effect, providing a broad application prospect.

BACKGROUND:Bone tissue remodeling is closely related to stress loading.Currently,there are few studies or guidelines on the relationship between bone and occlusal adjustment of implant prostheses and there is also a lack of scientific evidence. OBJECTIVE:To investigate the effects of different implant occlusal gaps on stress distribution,stress peak and displacement at the implant-bone interface under Ⅰ-Ⅳ bone conditions by a finite element method. METHODS:After scanning the equal-scale tooth model with an optical scanner,equal-scale models of the upper right first molar Straumann 4.8×8 mm BL RC implant and its related components was constructed using Solidworks 2022.Then,using Mimics,Geomagic,and Solidworks software,the maxillary and mandibular bone models of class Ⅰ-Ⅳ bones were established based on the bone classification proposed by ZARB and LEKHOLM in the literature,and the NORTON and TRISI bone density classification method.The models were assembled with the occlusal gaps of 0,20,40,60,80,and 100 μm for the restorations,and an additional set of homogeneous models without density ratio settings was constructed for comparison.After the above models were imported into Hypermesh for meshing,the material assignment,boundary constraints and parameter setting were performed for the finite element analysis.Finally,250 N was used as the loading force to simulate the maxillary and mandibular stress conditions.Stress distribution,peak stress and displacement of the implant-bone interface in each group of models were analyzed and compared. RESULTS AND CONCLUSION:Under the same loading conditions,the stresses in the implant restorations were evenly distributed with the occlusal contact points.When the occlusal gap reached 80 and 100 μm,stress interruptions occurred in the implant crowns under class Ⅰ bone and class Ⅱ,Ⅲ and Ⅳ bones,respectively.The displacement of the implant-bone interface was mainly concentrated in the cortical bone region around the implant and transmitted down the long axis of the implant to the cancellous bone region at the bottom.With the changes of class Ⅰ-Ⅳ jaw bones,the displacement and Von Mises stress in the cortical bone region increased in all groups,and were greater than those in the cancellous bone region.The Von Mises stress in the cancellous bone region was similar to that in the cortical bone region except that it showed a downward trend from class Ⅱ bone.However,when the occlusal gap increased,the stress and displacement peak values in the cortical bone and the cancellous bone showed a decreasing trend.The stress of the implant-bone interface was between 20 MPa and 60 MPa when the occlusal gap was 0-40 μm for class Ⅱ-Ⅳ bones and 60 μm for class Ⅳ bone,and the stress of the other groups was less than 20 MPa.The Von Mises stress was mainly concentrated in the neck of the implant,and the peak value of von Mises stress in class Ⅱ-Ⅳ bones with the occlusal gap of 20 μm was higher than that(144.10 MPa)in class Ⅰ bone with the occlusal gap of 0 μm.In the homogeneous model with different elastic moduli,the distribution of stress and displacement was more uniform than that in the heterogeneous model and the occlusal space should increase with the decrease of jaw bone density in clinical practice.To conclude,from the perspective of biomechanics,the alveolar bone should be taken into account in the occlusal adjustment of implant denture.An occlusal gap of 20-40 μm between a single dental implant and a natural tooth in the opposite jaw is a relatively suitable solution for occlusal adjustment under different bone conditions.However,due to the particularity of finite element analysis method,it needs to be further studied in combination with clinical practice.

Objective:To explore the application of microfluidic chip in detection of hereditary deafness-associated hotspot mutations.Methods:The dedicatedly designed and fabricated microfluidic chip was integrated with kompetitive allele-specific polymerase chain reaction amplification system, scanned via laser-excited confocal fluorescence scanner, and finally analyzed programmatically to acquire the typing results of the 23 mutation sites of the four common genes associated with hereditary hearing loss. Dried blood spots were collected from 276 neonates containing the 131 cases with hearing loss who were born in 2019 in Chengdu (deafness group) and the 145 cases with normal hearing who were born in 2020 in Chengdu (control group), and analyzed by the microfluidic chip to evaluate its clinical performance.Results:By cluster analysis, the microfluidic chip correctly analyzed the 23 positive reference samples and acquired the same typing results as their actual results, with a limit of detection of 1 mg/L. For the 276 newborn blood spots, the detection results of the microfluidic chips were confirmed to be correct by the contrasting methods. Among Deafness Group, 66 (50.4%) tested positive for the selected 23 mutation hotspots; among Control Group, 40(27.6%) were positive. Among these mutations, c.109G>A of the GJB2 gene was the most prevalent one, whose carrier rate in deafness group and control group were 46.6%(61/131) and 23.4% (34/145), respectively.Conclusions:The micro-fluidic chip system was succeeded in fulfilling the hereditary deafness-related mutation detection, and offered many advantages including high specificity, avoiding the amplicon carryover contamination, simplifying the entire experimental operation process and short detection time, so as to better meet the detection requirement of genetic testing for deafness in newborn screening and other fields.

Objective:To investigate the predictive value of preoperative D-dimer level for futile recanalization (FR) after mechanical thrombectomy (MT) in patients with acute ischemic stroke (AIS).Methods:It was a nested case-control study. A total of 116 patients with large vessel occlusion (LVO) stroke, who underwent successful recanalization (modified Thrombolysis in Cerebral Infarction, mTICI≥2b) after MT at the Stroke Unit of Beijing Hospital from August 2018 to January 2022,were consecutively enrolled, including 72 males (62.1%) with the age of (72.8±13.1) years. According to the 3-month modified Rankin Scale (mRS) score after MT, patients were divided into the meaningful recanalization group (mRS 0-2, n=41) and the futile recanalization group (mRS 3-6, n=75). The baseline clinical data of enrolled patients was collected. Logistic regression analysis was used to identify the independent risk factors for FR after MT in patients with AIS. Receiver operating characteristic (ROC) curve was used to evaluate the predictive value of D-dimer for FR. Results:Multivariate logistic regression analysis showed that high baseline systolic blood pressure (SBP) ( OR=1.038, 95% CI: 1.012-1.065, P=0.004), baseline National Institutes of Health Stroke Scale (NIHSS) score≥12 ( OR=10.157, 95% CI: 3.624-28.470, P<0.001) and high preoperative D-dimer level ( OR=4.536, 95% CI: 1.379-14.922, P=0.013) were independent predictors of FR after MT in AIS patients with LVO. ROC curve analysis indicated a good predictive value of preoperative D-dimer for the occurrence of FR ( AUC=0.733, 95% CI: 0.638-0.829, P<0.05), the optimal cut-off value of D-dimer was 2.65 μg/L(Lg), with the Youden index, sensitivity, specificity and accuracy of 0.435, 53.3%, 90.2% and 66.4%, respectively. Conclusion:High preoperative D-dimer level is an independent predictor of futile recanalization after MT in AIS patients with LVO, which shows good predictive ability for futile recanalization.