Objective: To observe the effect of infiltration resin combined with cold light whitening in the treatment of dental fluorosis. Methods: According to the distance between teeth and the long axis of each tooth, 18 anterior teeth were divided equally and randomly between group A and B. Samples in group A underwent cold light whitening, while samples in group B were treated with infiltration resin combined with cold light whitening. The color was measured before and after the treatment. Then, 6 teeth (the first subgroup) were randomly selected from the 18 anterior teeth after measurement for scanning electron microscopy (SEM) to observe the surface microstructure of the teeth. Then, another 6 teeth (the second subgroup) were selected from the remaining 12 teeth for the measurement of the color level and ΔE after being dyed with tea. Results: After treatment, the color level changed significantly in group A and B (P < 0.05), ΔE in group A and B was 13.75, 14.98. There was no significant difference in the color level change between group B and group A, there was a significant difference in the ΔE between the two groups (t = -3.58, P < 0.05). SEM showed that the enamel surface was intact and that the enamel space was filled in group B. In group A, the enamel surface was reduced and uneven, and the characteristic badminton racquet shape of the enamel was not obvious. The color level was lower in both groups after staining, and these differences were significant (P < 0.05), ΔE in group A and B was 19.69, 18.95. There was no significant difference in the color level (t = 1.00, P > 0.05) and ΔE (t = 0.02, P > 0.05) between two groups. Conclusion Cold light whitening combined with infiltration resin is better for treating dental fluorosis than cold light whitening alone.

Exosomes are vesicles with a double globular membrane of lipids that can be secreted by a variety of cells, including stem cells. Exosomes have unique biological characteristics and irreplaceable powerful functions which play an important role in intercellular communication. The various cytokines, signal proteins, lipids and regulatory nucleic acids contained in stem cell exosomes can play a protective role against the injury of kidney, liver, heart, blood vessels and nerves. Stem cell exosomes delay the process of intervertebral disc degeneration by inhibiting the apoptosis of nucleus pulposus cells and increasing the synthesis of extracellular matrix, etc. The mechanism of its role is mainly through miRNA and related signaling pathways. Exosomes contain complex components. Although the mechanism of action of exosomes in intervertebral discs has been preliminarily explored, the components contained in exosomes are complex and the specific situation has not been fully understood, which still needs further study. In this review, the characteristics and functions of stem cell exosomes, extraction, identification and storage methods, the impacttovarious other tissues, as well as the effects on intervertebral discs and their mechanisms were elaborated in order to provide a basis for the study of intervertebral disc degenerative diseases.

Objective To observe the clinical features and evaluate the risk factors affecting prognosis in patients with secondary sepsis of gastrointestinal perforation (GIP). Methods A retrospective cohort study was conducted, and the patients with GIP admitted to the Department of General Surgery of Affiliated Shuyang People's Hospital of Xuzhou Medical University from January 1, 2014 to April 30, 2017 were enrolled, according to the presence or absence of sepsis occurrence, they were divided into GIP with and GIP without sepsis groups. The difference of gender, age, the time between the onset of GIP and the occurrence of sepsis, infection situation, body temperature, heart rate, respiratory frequency, white blood cell count (WBC), systemic inflammatory response syndrome (SIRS) in accord with standard, C-reactive protein (CRP), blood sugar, mean arterial pressure (MAP), lactic acid, number of cases having undergone laparoscopic surgery, sequential organ failure score (SOFA) and quick sequential organ failure score (qSOFA), Glasgow coma score(GCS), length of stay in intensive care unit (ICU), the total length of stay in hospital were compared;the status of survival and prognosis was assessed on day 30 by the Glasgow Outcome Scale (GOS). The indicators with statistical significance in the two groups were brought into the Cox regression model to analyze the independent risk factors affecting the prognosis of the patients. Results Fifty-eight patients with GIP were enrolled in this study. Among them, 22 cases developed secondary sepsis (GIP with sepsis group, there were 50.0% cases with single organ failure and 50.0% cases with multiple-organ failure, cases only in accord with 0-1 SIRS criteria accounting for 81.8%, and the mortality of secondary sepsis being 31.8%). No sepsis occurred in 36 patients (GIP without sepsis group). In GIP with sepsis group, the age, blood glucose, lactic acid, SOFA score, qSOFA, and the length of stay in ICU were significantly higher than those of GIP without sepsis group [age (years): 68.7±15.9 vs. 56.1±17.2, blood glucose (mmol/L): 6.9±2.3 vs. 5.9±1.2, lactic acid (mmol/L): 2.9±1.3 vs. 1.2±0.7, SOFA score: 5.6±3.2 vs. 0.5±0.4, qSOFA score: 1.0±0.9 vs. 0.3±0.1, the length of stay in ICU (days): 1.0 (0-4.0) vs. 0.1 (0-2.0), all P < 0.05], while MAP, GCS, and GOS scores in GIP with sepsis group were significantly lower than those in GIP without sepsis group [MAP (mmHg, 1 mmHg =0.133 kPa): 83.6±18.7 vs. 100.0±14.3, GCS score: 12.8±3.5 vs. 14.5±0.5, GOS score: 3.5±1.9 vs. 4.9±0.2, all P < 0.01]. Cox multivariable regression analysis showed: only low MAP and low GCS score were the independent risk predictors of death outcome for GIP with sepsis, the relative risk (RR) was 0.896 [95% confidence interval (CI) = 0.815-0.984, P = 0.022] and 0.585 (95%CI = 0.395-0.866, P = 0.007) respectively. Conclusion Patients with secondary sepsis following GIP have relatively high morbidity and much more risk factors, but only low MAP and low GCS score are closely associated with its high risk of death.

OBJECTIVETo find out the occurrence of cesarean section (CS) and related factors among child-bearing women in China.

METHODSThe survey was conducted during October, 2010 in 40 counties selected from 30 provinces. Size proportional sampling method was employed in sampling. A face to face questionnaire investigation was conducted among 8 420 women who experienced pregnancies from 1978 to 2010. Information on demographic characteristics, history of pregnancy and birth were obtained, and related factors of CS occurrence were analyzed.

RESULTSA total of 11 440 living births have been given by 8 420 women, and 1 725 CS happened. As the time goes on, there is a growing trend of CS occurrence, from 2.0% (14/701) in 1978-1985 to 36.6% (813/2 224) in 2006-2010, and there is a most fast increase from 2001 to 2010. CS rate in Mid-China (42.3%, 257/608) is the highest from 2006 to 2010. And also, the rate of CS requested by the pregnant women or their family members was increasing year by year, from 14.3% (2/14) in 1978-1985 to 43.7% (255/813) in 2006-2010. Women who were above 25 years old (21.4%, 960/4 485) , with an education degree of high school or above (24.5%, 568/2 317), engaged in nonagricultural work (22.4%, 663/2 956), living in eastern provinces of China (18.6%, 757/4 074), fetal malposition (45.4%, 247/544) , with a heavier birth weight(4 000 gram or above) (36.5%, 175/479) , have accepted B ultrasound exam (18.8%, 1 633/8 687) with an increasing of blood pressure (28.0%, 172/614) and convulsion experiences (24.8%, 131/528) during pregnancy were more likely to have CS.

CONCLUSIONThe CS rate among child-bearing women in China was rather high, and was related with factors of demographic characteristics(age of childbearing, education, vocation, residence) and some medical factors(neonatal weight, having accepted B ultrasound exam, fetal malposition, an increase of blood pressure and convulsions during pregnancy).

Cesarean Section ; statistics & numerical data ; trends ; China ; Demography ; Female ; Humans ; Pregnancy ; Risk Factors ; Surveys and Questionnaires

Objective To explore the management strategy and indications for revisionary internal fixation after percutaneous kyphoplasty/percutaneous vertebroplasty (PKP/PVP) in cancellous vertebral fractures.Methods A retrospective analysis was made of the 676 cases of single-segment PKP/PVP at Department of Orthopaedics,The Affiliated Hospital to Qingdao University from January 2008 to January 2019.They were subjected to 4 different managements after their primary PKP/PVP:rehabilitation without any treatment in 637 cases,conservative treatment in 19 cases (including 3 ones who refused any revision),KP/VP revision in 12 cases and internal fixation revision in 8 cases.The rate of volume reduction after bone cement dispersion (Vx) was calculated using software Mimics 17.0 on the basis of primary CT data of all the patients.The correlation regression analysis was made between the revision rate and the approximate quantization value of Vx.The Glasgow Coma Score (GCS) of conscious state was used to evaluate the 39 patients after failure of their primary surgery before the surgical strategy for revision was worked out.The cobb angle,pelvic incidence angle (PI),pelvic inclination angle (PT),sacral inclination angle (SS),sagittal deviation (SVA),pain visual analogue scale (VAS) were measured and recorded before operation and at the last follow-up for the KP/VP revision group and internal fixation revision group,indicated as △cobb,△PI,△PT,△SS,△SVA and △VAS,respectively.The indexes were compared between the 2 groups.Results The incidence of osteoporotic vertebral fractures treated with internal fixation revision was 1.18％ (8/676).The correlation between Vx and revision rate was y =0.53 + 0.04x (P ＜ 0.05).The regression analysis showed that Vx was positively correlated with the revision rate (r2 =0.860,P =0.001) and the fitting curve was correlated (r2 =0.916,P =0.001).The GSC scores revealed 31 normal,6 mild disturbance and 2 moderate disturbance cases.There were no significant differences in gender,age or VAS scores between the KP/VP revision group and the internal fixation revision group (P ＞ 0.05).There was a significant difference in △cobb between the 2 revision groups (6.3° ± 7.5° versus 19.2° ± 14.8°) (P ＜0.05),but there were no significant differences between the 2 groups in △PI (4.1°±5.2° versus 3.3°±6.7°),△PT (0.7°±4.6° versus 0.4° ± 3.2°),△SS (3.7° ± 6.2° versus 3.1° ± 5.3°) or △SVA (-3.2 ± 11.9 mm versus-7.9 ± 9.5 mm) (P ＞ 0.05).Conclusions The outcomes of primary PKP/PVP have a great impact on the decision-making of internal fixation revision.The mode and extent of diffusion after initial vertebral cement perfusion are particularly related to the revision rate.The revision plan should depend on clinical symptoms.The internal fixation revision should be individualized to ensure the quality of life of the patients in line with the principles of "resolving symptoms" and "moderate correction".

Objective:To evaluate the volume changes of cervical longus and cervical extensor after anterior cervical discectomy and fusion (ACDF), and the correlation with the clinical efficacy of patients.Methods:All of 57 patients with cervical spondylotic myelopathy who underwent single-segment ACDF surgery from January 2013 to December 2018 were analyzed. The follow-up time was 23.0±4.8 months (range 16-34 months). All included subjects underwent MR examination within 1 week before operation and 3rd, 12th months after operation and at the last follow-up. The axial section cross section area (AxCSA) of the cervical longus and the ratio of length to short diameter line (RLS) at the level of each disc of C 2-C 7 were measured on the axial T2WI. Calculate the volume of the cervical longus based on the layer thickness. At the same time, measure the cervical extensor cross-sectional area (CESA) of the same level including the multifidus, cervical semispinous muscle, semispinous head, splinter head, and cervical splinter muscles, and compare CESA with the corresponding vertebral cross-sectional area (VBA). The ratio is analyzed as the volume of the neck extensor muscle, namely CESA/VBA. At the 3rd and 12th months after operation and at the last follow-up, the axial pain was assessed by visual analogue scale (VAS) for assessing pain, and the modified Japanese Orthopedic Association score (mJOA) and the neck dysfunction index (NDI) were used to assess the functional status of the cervical spine. Analyze the morphological changes of thecervical longus and extensor cervical muscles before and after the operation and during the follow-up period, and analyze the correlation with VAS, mJOA, and NDI. Results:Compared with the preoperative period, the average AxCSA of the surgical segment decreased at the 3rd and 12th months after the operation and at the last follow-up. The difference was statistically significant ( F=24.113, P<0.05), which was changed from 140.84±19.51 mm 2 respectively reduce to 117.74±17.15 mm 2 ( t=6.714, P<0.05), 116.37±18.67 mm 2 ( t=6.841, P<0.05) and 116.27±18.65 mm 2 ( t=6.873, P<0.05). Compared with preoperatively, they were reduced by 16.40%, 17.37% and 17.45%, respectively, while the average RLS of surgical segments increased slightly, and the difference was statistically significant ( F=22.612, P<0.05), which increased from preoperative 1.97±0.67 to 2.73±0.60 (38.58% increased, t=6.380, P<0.05), 2.82±0.64 (43.15% increased, t=6.926, P<0.05) and 2.74±0.62 (39.09% increased, t=6.368, P<0.05). The volume of thecervical longus of the patients decreased after the operation, and the difference was statistically significant ( F=64.511, P<0.05), which decreased from 8853.48±458.65 mm 3 before the operation to 7834.53±461.59 mm 3 (11.51% decreased, t=11.822, P<0.05), 7926.42±456.24 mm 3 (10.47% decreased, t=10.819, P<0.05), 7892.38±450.78 mm 3 (10.86% decreased, t=11.283, P<0.05). There were no statistically significant differences in the non-surgical segment AxCSA, RLS and the volume of thecervical longus at the 3rd and 12th months after surgery and the last follow-up ( P>0.05). There was no statistically significant difference of CESA and CESA/VBA compared to preoperative in the surgical segment and non-surgical segment ( P>0.05). Pearson correlation analysis showed that the volume of cervical longus and VAS at the 3rd month ( r=-0.308, P<0.05), the 12th month ( r=-0.210, P<0.05) and the last follow-up ( r=-0.404, P<0.05) were negatively correlated; Among the volume of cervical longus and NDI in the 3rd month ( r=-0.511, P<0.05), 12th month ( r=-0.518, P<0.05) and the last follow-up ( r=-0.352, P<0.05), there was a negative correlation; However, there was no statistically significant correlation between the cervical longus muscle volume and mJOA at each follow-up time point ( P>0.05); There was no significant correlation between CESA/VBA and VAS, NDI, and mJOA at the 3rd, 12th and last follow-up ( P>0.05). Conclusion:The volume and morphology of cervical longus after ACDF was significantly reduced compared with that before the operation, but the volume and morphology of the cervical extensor muscle did not change significantly. ACDF surgery mainly affects the cervical longus corresponding to the surgical segment, and the volume is negatively correlated with the VAS and NDI during follow-up.

Objective:To explore the effect of minimally invasivetransforaminal lumbar interbody fusion (MIS-TLIF) on lumbar multifidus muscle using MRI techniqueandits clinical significance.Methods:From September 2016 to July 2019, 23 patients who underwent MIS-TLIF surgery for unilateral symptomatic disc herniation in unilateral segments (L 3,4, L 4,5, L 5S 1) of Qingdao University Affiliated Hospital were studied. Their lumbar MR examination was performed 1 week before surgery, and 3 and 6 months after surgery. The axial section of multifidus muscle cross section area (AxCSA) was measured on the axial T2WI image of each intervertebral disc level before and after the operation. The ratio of long and short lines (RLS) was calculated, andthe ratio of axial section of muscle fat infiltration cross section area (FLSA) and AxCSAwasrecorded as FLSA/AxCSA. The changes of various indexes of multifidus muscle in the affected side and the healthy side of the lumbar spine before and after the operation were compared, and the effect of the MIS-TLIF procedure on the morphology of the multifidus muscle was observed. Magnetic resonance spectroscopy (MRS) measurements of the muscle cross-section of the affected side were performed before and 6 months after the operation. The integral value of intracellular lipid (IMCL) and extracellular lipid (EMCL) of 1H spectrum muscle cells was compared, while the degree of fat infiltration was measured. Results:Patients with single-segment lumbar disc herniation had larger AxCSAin the healthy side than the affected side before surgery in surgical level ( t=6.611, P<0.05), and the muscle AxCSAin the healthy side was larger than the affected side in non-surgical levels ( t=-6.682, P<0.05), both suggested preoperative muscle volume advantage in the healthy side; no difference in bilateral AxCSA at 3 months was found after surgeryin surgical levels ( t=0.197, P> 0.05)and non-surgical levels ( t=-1.631, P> 0.05), which suggested bilateral muscle volume equal advantageat short-term follow-up. The FLSA/AxCSA of affected segment before and after 3 months was 9.5%±3.8% and 8.7%±1.5%, and the difference was statistically significant ( t=3.163, P<0.05); the RLS of affected segment before and after 3 months was 3.3%±0.24% and 2.7%±0.83%, and the difference was statistically significant ( t=3.42, P<0.05). The medians of EMCL/IMCL before and after 6 months of MRS were 2.010 and 1.475, respectively, and EMCL decreased after 6 months ( Z=0.48, P<0.05). Conclusion:Patients with single-segment lumbar disc herniation have different morphology of bilateral multifidus muscle before surgery. MIS-TLIF has little effect on the multifidus muscle of the surgical side. MIS-TLIF significantly reduces extracellular lipid accumulation, promotes intracellular transfer, and increases intracellular fat metabolism. Its retention of muscle attachment points and limited fixation can also reshape compensatory muscle atrophy.

Objective:To investigate the effects of exosomes of human nucleus pulposus cells (NPCs) on the differentiation of urine derived stem cells (USCs) into nucleus pulposus-like cells.Methods:USCs and NPCs were isolated and cultured in vitro. The exosomes of NPCs were extracted and detected by Western-blot. USCs cytoplasm was transfected with GFP lentivirus, while nucleus was transfected with DAPI dye. The NPCs exosomes were transfected with PKH26 dye. After co-incubation for 12 h, USCs and NPCs exosomes were observed by macroscopy. USCs differentiation was induced by NPCs exosomes and non-contact co-culture methods. The relative expression of marker gene mRNA of nucleus pulposus cells in each group and the absorbance at 450 nm wavelength were detected.Results:The isolated USCs had the ability to differentiate into osteocytes, adipocytes and chondrocytes with high expression of marker CD29 (99.57%), CD44 (97.46%) and CD73 (97.71%) and with low expression of negative proteins CD31 (0.59%) and CD45 (0.19%). The isolated NPCs highly expressed nuclear pulposus cell marker COL2A1, ACAN and SOX-9. The exosomes extracted from NPCs showed high expression of exosome marker CD63, CD81 and Tsg101. After 12 h co-incubation, NPCs exosomes fused with USCs membrane and appeared in the cytoplasm of USCs. At 3, 5 and 7 days of co-culture, the absorbance value of USCs cells in exosome group (0.44±0.004, 0.76±0.004, 0.82±0.006) was higher than that in co-culture group (0.39±0.022, 0.63±0.035, 0.69±0.012) ( P<0.05). The mRNA relative expression of USCs nucleus pulposus marker genes ACAN (1.80±0.31, 3.50±0.21, 5.35±0.31, 7.46±0.12), COL2A1 (1.43±0.15, 4.33±0.23, 6.89±0.22, 8.11±0.31), SOX-9 (2.21±0.13, 3.13±0.11, 3.96± 0.14, 4.52±0.26) and HIF-1α (1.45±0.16, 2.14±0.21, 4.31±0.41, 4.01±0.25) in exosomes group were significantly higher than those in the control group ( P<0.05) at the 3rd, 7th, 14th and 21st days. The mRNA relative expression of USCs nucleus pulposus marker genes ACAN (5.69±0.21, 6.69±0.13), COL2A1 (6.33±0.17, 7.89±0.15), SOX-9 (4.19±0.29, 4.38±0.12), HIF-1α (4.49±0.32, 4.96±0.26) in exosomes group were significantly higher than those ACAN (3.69±0.35, 5.13±0.23), COL2A1 (3.40±0.16, 6.79±0.19), SOX-9 (2.26±0.32, 3.69±0.26), HIF-1α (2.39±0.11, 3.96±0.13) in non-contact co-culture group ( P<0.05) at the 14th and 21st days. Conclusion:Human nucleus pulposus exosomes could induce differentiation of human USCs into nucleus pulposus-like cells in vitro. Compared with non-contact co-culture, exosomes have higher induction efficiency and can better maintain the proliferation activity of nucleus pulposus-like cells

Spinal cord injury is a catastrophic injury causing lifelong severe disabilities, and poses a great burden to the individuals, families and society. In order to promote the standardization in treatment of traumatic spinal cord injury, the consensus on the evaluation, treatment and rehabilitation of traumatic spinal cord injury was suggested by experts, who came from authoritative multicenter in China. The expert consensus, which formed a standardization process from the first aid clinical treatment to rehabilitation of spinal cord injury, shall give a better practical guide for clinic and rehabilitation physicians.

OBJECTIVE: To compare the effectiveness between unilateral biportal endoscopic lumbar interbody fusion (ULIF) and endoscopic transforaminal lumbar interbody fusion (Endo-TLIF) in treatment of lumbar spinal stenosis combined with intervertebral disc herniation. METHODS: A clinical data of 64 patients with lumbar spinal stenosis and intervertebral disc herniation, who were admitted between April 2020 and November 2021 and met the selection criteria, was retrospectively analyzed. Among them, 30 patients were treated with ULIF (ULIF group) and 34 patients with Endo-TLIF (Endo-TLIF group). There was no significant difference in baseline data such as gender, age, disease duration, lesion segment, preoperative visual analogue scale (VAS) score of low back pain and leg pain, Oswestry disability index (ODI), spinal canal area, and intervertebral space height between the two groups ( P>0.05). The operation time, intraoperative blood loss, hospital stays, and postoperative complications were compared between the two groups, as well as the VAS scores of low back pain and leg pain, ODI, and imaging measurement indicators (spinal canal area, intervertebral bone graft area, intervertebral space height, and degree of intervertebral fusion according to modified Brantigan score). RESULTS: Compared with the Endo-TLIF group, the ULIF group had shorter operation time, but had more intraoperative blood loss and longer hospital stays, with significant differences ( P<0.05). The cerebrospinal fluid leakage occurred in 2 cases of Endo-TLIF group and 1 case of ULIF group, and no other complication occurred. There was no significant difference in the incidence of complications between the two groups ( P>0.05). All patients in the two groups were followed up 12 months. The VAS scores of lower back pain and leg pain and ODI in the two groups significantly improved when compared with those before operation ( P<0.05), and there was no significant difference between different time points after operation ( P>0.05). And there was no significant difference between the two groups at each time point after operation ( P>0.05). Imaging examination showed that there was no significant difference between the two groups in the change of spinal canal area, the change of intervertebral space height, and intervertebral fusion rate at 6 and 12 months ( P>0.05). The intervertebral bone graft area in the ULIF group was significantly larger than that in the Endo-TLIF group ( P<0.05). CONCLUSION For the patients with lumbar spinal stenosis combined with intervertebral disc herniation, ULIF not only achieves similar effectiveness as Endo-TLIF, but also has advantages such as higher decompression efficiency, flexible surgical instrument operation, more thorough intraoperative intervertebral space management, and shorter operation time.
Humans ; Spinal Stenosis/surgery* ; Low Back Pain/surgery* ; Blood Loss, Surgical ; Intervertebral Disc Displacement/surgery* ; Lumbar Vertebrae/surgery* ; Retrospective Studies ; Spinal Fusion