BACKGROUND:Ankylosing spondylitis is a chronic inflammatory disease with chronic rheumatic immunity.Soft tissue ossification and fusion and spinal stiffness can cause biomechanical changes. OBJECTIVE:To reconstruct the lumbar-sacral intervertebral disc in ankylosing spondylitis patients with lumbar kyphosis by finite element analysis,and to study the range of motion of each segment of T11-S1 and the biomechanical characteristics of annulus fibrosus and nucleus pulposus. METHODS:The imaging data were obtained from an ankylosing spondylitis patient with lumbar kyphosis.The original CT image data of continuously scanned spine were imported into Mimics 21.0 in DICOM format,and T11-S1 was reconstructed respectively.The established model was imported into 3-Matic software in the format of"Stl"to reconstruct the intervertebral disc,and the fibrous intervertebral disc model was obtained.The improved model was further imported into Hypermesh software,and the vertebra,nucleus pulposus,annulus fibrosus and ligament were mesh-divided.After the material properties were given,the model was imported into ABAQUS software to observe the range of motion of each vertebral body in seven different working conditions of T11-S1,and analyze the biomechanical characteristics of each segment of annulus fibrosus and nucleus pulposus. RESULTS AND CONCLUSION:(1)The range of motion of L1 vertebrae was higher than that of other vertebrae under six different working conditions:extension,forward flexion,rotation(left and right),and lateral flexion(left and right).The maximum range of motion was 2.18° during L1 vertebral flexion,and the minimum range of motion was 0.12° during L5 vertebral extension.(2)The annular fiber flexion at L2-L3 segments was greater than the extension(P<0.05),and the annular fiber flexion at L3-L4 and L4-L5 segments was less than the extension(P<0.05).The left rotation of L1-L2 annular fibers was greater than the right rotation(P<0.05).The left flexion of the annulus was greater than the right flexion in L1-L2,L2-L3,L3-L4,L4-L5 and L5-S1 segments(P<0.05).(3)The nucleus pulposus stresses of T11-L12,L1-L2,L2-L3,L3-L4 and L4-L5 segments in forward flexion were greater than in extension(P<0.05).The left rotation of T12-L1 and L3-L4 segments was smaller than the right rotation(P<0.05),and that of T11-T12,L1-L2,and L2-L3 segments was larger than the right rotation(P<0.05).The left flexion was larger than the right flexion in the T11-S1 segment.(4)It is concluded that in ankylosing spondylitis patients with lumbar kyphosis,the minimum range of motion of the vertebral body is located at the L5 vertebral body in extension.To prevent fractures,it is recommended to avoid exercise in the extension position.During the onset of lumbar kyphosis in patients with ankylosing spondylitis,the maximum stress of the annulus fibrosus and nucleus pulposus is located in the L1-L2 segment,which is fixed and will not alter with the change of body position.The late surgical treatment and correction of deformity should focus on releasing the pressure of the annulus fibrosus and nucleus pulposus in this segment to avoid the rupture of the annulus fibrosus and the injury of the nucleus pulposus.

Objective:To establish a rapid and accurate method for the detection of Klebsiella pneumoniae carbapenemase (KPC) carbapenemase gene based on recombinase aided amplification (RAA)-CRISPR-Cas13a (CRISPR-Cas13a) technology. Methods:Twenty-five clinical isolates of carbapenem-resistant Klebsiella pneumoniae (CRKP) and five carbapenem-sensitive Klebsiella pneumoniae (CSKP) strains preserved in 2020-2021 in Beijing Chuiyangliu Hospital were randomly collected, and the total DNA samples of the strains was extracted. RAA primers specific for KPC DNA and CRISPR RNA (crRNA) were designed to establish a rapid and accurate method for the detection of KPC carbapenemase gene based on RAA-CRISPR-Cas13a technology. The method was evaluated by plasmids and clinical sample strains, and the detection was also performed by Quantitative real-time PCR (qPCR) method to compare the detection rate and consistency of the two methods. Results:The RAA-CRISPR-Cas13a method can detect KPC plasmids and samples with a sensitivity of 1 copy/μl, which is higher than that of qPCR (10 1 copies/μl). Among the 30 clinical strains (including 25 CRKP strains and 5 CSKP strains), 23 strains were detected to carry KPC gene by both RAA-CRISPR-Cas13a method and qPCR method, and 7 strains were not detected with KPC gene. The detection rate of KPC gene in the 25 CRKP strains was 92% (23/25). The positive coincidence rate of the two methods was 100% (23/23). Conclusions:This study combined RAA amplification technology with CRISPR-Cas13a technology to establish a rapid and accurate method for detecting KPC carbapenemase gene. The method is useful for accurate screening of KPC carbapenemase-producing strains. It has a wide application prospect in drug resistance monitoring and infection control.

AIM: To investigate the potential causal relationship between gut microbiota(GM)and primary open-angle glaucoma(POAG)based on a two-sample Mendelian randomization(MR)analysis.METHODS: The exposure data was derived from the Genome-Wide Association Studies(GWAS)of GM at the University of Bristol, while the outcome data for POAG was sourced from the MRC Integrative Epidemiology Unit(IEU)Open GWAS database. In this study, inverse variance weighted(IVW), MR Egger, weighted median(WM), Simple Mode, and Weighted Mode were analyzed to investigate the potential causal relationships between GM and POAG. IVW was used as the primary method for this study, and sensitivity analysis was conducted to assess the reliability of the MR analysis.RESULTS: The IVW analysis revealed that Butyrivibrio(OR=1.170, 95%CI: 1.057-1.295, P=0.002), Howardella(OR=1.188, 95%CI: 1.043-1.355, P=0.010), and LachnospiraceaeUCG001(OR=1.229, 95%CI: 1.016-1.485, P=0.033)were correlated with the risk of POAG. Conversely, Candidatus Soleaferrea(OR=0.810, 95%CI: 0.670-0.981, P=0.031), Ruminococcustorquesgroup(OR=0.656, 95%CI: 0.453-0.950, P=0.026), and RuminococcaceaeUCG013(OR=0.770, 95%CI: 0.598-0.990, P=0.041)were protective factors for POAG. Sensitivity analysis showed that there were no heterogeneity and pleiotropy among the instrumental variables.CONCLUSION: The MR study indicated a causal relationship between GM and POAG. Given the sight-threatening characteristic of POAG, early identification and intervention in the relative factors was significant for the prognosis of POAG.

BACKGROUND:Ankylosing spondylitis is a progressive inflammation of spinal stiffness deformity caused by tissue ossification and fibrosis.The posture of ankylosing spondylitis patients is abnormal and their activities are limited that minor injuries can lead to thoracolumbar fractures.Traditional medical image observation limits doctors'preoperative decision planning and postoperative disease prevention for ankylosing spondylitis treatment. OBJECTIVE:Based on the spinal model of ankylosing spondylitis patients before and after posterior spinal cancellous ossification osteotomy("Y"osteotomy for short),to explore the biomechanical changes of"Y"osteotomy and fixation in the treatment of ankylosing spondylitis. METHODS:Based on the preoperative and postoperative CT images of an ankylosing spondylitis patient who went to the Second Affiliated Hospital of Inner Mongolia Medical University,a three-dimensional spine model(T11-S1)before and after"Y"osteotomy(L3 osteotomy)was reconstructed in Mimics 19.0 software.A 7.5 Nm torque was applied to the top of T11 vertebral body to simulate the movement of the spine under six conditions:flexion,extension,left bending,right bending,left rotation and right rotation.Finally,the range of motion of each vertebral body,the stress of each intervertebral disc,and the stress of the screw rod system were simulated. RESULTS AND CONCLUSION:(1)After"Y"type osteotomy and posterior fixation,the range of motion of all vertebrae in the spine decreased,and the loss rate of upper vertebrae was large(L1:77.95%).(2)The maximum stress of the spinal intervertebral disc before operation occurred at the L1-L2 segment(0.55 MPa),and the maximum stress of the spinal intervertebral disc after operation occurred at the T11-T12 segment(0.50 MPa),and the stress of intervertebral disc below T12 was far less than that before operation.(3)The maximum stress of the screw rod system(166.67 MPa)occurred in the upper and middle segments of the rod body and the root of the pedicle screw.(4)In conclusion,the"Y"type posterior fixation operation enhances the stability of the spine and reduces the range of motion of the spine.The vertebral body decompression of the fixed segment is great and the stress-shielding phenomenon of the lower vertebral body is significant.The stiffness of the rod body and the stress concentration area of the pedicle screw should be strengthened to avoid the fracture of the rod caused by stress fatigue.

Objective:To prepare the chitin/hyaluronic acid/collagen hydrogel loaded with mouse adipose-derived stem cells and to explore its effects on wound healing of full-thickness skin defects in rats.Methods:The research was an experimental research. Chitin nanofibers were prepared by acid hydrolysis and alkaline extraction method, and then mixed with hyaluronic acid and collagen to prepare chitin/hyaluronic acid/collagen hydrogels (hereinafter referred to as hydrogels). Besides, the hydrogels loaded with mouse adipose-derived stem cells were prepared. Thirty male 12-week-old guinea pigs were divided into negative control group, positive control group, and hydrogel group according to the random number table, with 10 guinea pigs in each group. Ethanol, 4-aminobenzoic acid ethyl ester, or the aforementioned prepared hydrogels without cells were topically applied on both sides of back of guinea pigs respectively for induced contact and stimulated contact, and skin edema and erythema formation were observed at 24 and 48 h after stimulated contact. Adipose-derived stem cells from mice were divided into normal control group cultured routinely and hydrogel group cultured with the aforementioned prepared hydrogels without cells. After 3 d of culture, protein expressions of platelet-derived growth factor-D (PDGF-D), insulin-like growth factor-Ⅰ (IGF-Ⅰ), and transforming growth factor β 1 (TGF-β 1) were detected by Western blotting ( n=3). Eight male 8-week-old Sprague-Dawley rats were taken and a circular full-thickness skin defect wound was created on each side of the back. The wounds were divided into blank control group without any treatment and hydrogel group with the aforementioned prepared hydrogels loaded with adipose-derived stem cells applied. Wound healing was observed at 0 (immediately), 2, 4, 8, and 10 d after injury, and the wound healing rate was calculated at 2, 4, 8, and 10 d after injury. Wound tissue samples at 10 d after injury were collected, the new tissue formation was observed by hematoxylin-eosin staining; the concentrations of interleukin-1α (IL-1α), IL-6, IL-4, and IL-10 were detected by enzyme-linked immunosorbent assay method; the expressions of CD16 and CD206 positive cells were observed by immunohistochemical staining and the percentages of positive cells were calculated. The sample numbers in animal experiment were all 8. Results:At 24 h after stimulated contact, no skin edema was observed in the three groups of guinea pigs, and only mild skin erythema was observed in 7 guinea pigs in positive control group. At 48 h after stimulated contact, skin erythema was observed in 8 guinea pigs and skin edema was observed in 4 guinea pigs in positive control group, while no obvious skin erythema or edema was observed in guinea pigs in the other two groups. After 3 d of culture, the protein expression levels of PDGF-D, IGF-I, and TGF-β 1 in adipose-derived stem cells in hydrogel group were significantly higher than those in normal control group (with t values of 12.91, 11.83, and 7.92, respectively, P<0.05). From 0 to 10 d after injury, the wound areas in both groups gradually decreased, and the wounds in hydrogel group were almost completely healed at 10 d after injury. At 4, 8, and 10 d after injury, the wound healing rates in hydrogel group were (38±4)%, (54±5)%, and (69±6)%, respectively, which were significantly higher than (21±6)%, (29±7)%, and (31±7)% in blank control group (with t values of 3.82, 3.97, and 4.05, respectively, Pvalues all <0.05). At 10 d after injury, compared with those in blank control group, the epidermis in wound in hydrogel group was more intact, and there were increases in hair follicles, blood vessels, and other skin appendages. At 10 d after injury, the concentrations of IL-1α and IL-6 in wound tissue in hydrogel group were significantly lower than those in blank control group (with tvalues of 8.21 and 7.99, respectively, P<0.05), while the concentrations of IL-4 and IL-10 were significantly higher than those in blank control group (with tvalues of 6.57 and 9.03, respectively, P<0.05). The percentage of CD16 positive cells in wound tissue in hydrogel group was significantly lower than that in blank control group ( t=8.02, P<0.05), while the percentage of CD206 positive cells was significantly higher than that in blank control group ( t=7.21, P<0.05). Conclusions:The hydrogel loaded with mouse adipose-derived stem cells is non-allergenic, can promote the secretion of growth factors in adipose-derived stem cells, promote the polarization of macrophages to M2 phenotype in wound tissue in rats with full-thickness skin defects, and alleviate inflammatory reaction, thereby promoting wound healing.

Objective To investigate the ameliorative effects and potential mechanism of Lithocarpus litseifoliu on renal function and inflammation in mice with hyperuricemic nephropathy(HN).Methods The HN model was established by the combined administration of adenine and potassium oxyzate.The mice were randomly divided into normal control group,model control group,benzbromarone group,and high,medium and low dose groups of Lithocarpus litseifoliu.Different drugs were given to the mice,and their body mass was recorded once a week.The levels of uric acid(UA),creatinine(Cr),urine protein(UP),blood urea nitrogen(BUN)and urine urea nitrogen(UUN)as well as the levels of tumor necrosis factor α(TNF-α)and interleukin 6(IL-6)in serum or urine of each group were collected and measured on the 21st day.Hematoxylin-eosin(HE)staining was performed to observe kidney tissue injury in mice;real-time PCR(RT-PCR)was performed to determine ATP-binding cassette subfamily G member 2(ABCG2),urate transporter protein(URAT1),glucose transporter protein 9(GLUT9),and cytosolic factor NF-κB p50(κB p50)in kidney tissues.Results Compared with the normal control group,the body mass of mice in the model control group was significantly lower after the second weeks of modeling(P＜0.05),and the levels of UA,Cr,UP,BUN,UUN,TNF-α,IL-6 contents and GLUT9 mRNA and κB p50 mRNA expression contents of kidney tissues were significantly higher(P＜0.01,P＜0.05).Compared with the model control group,the levels of Cr,UP,BUN and UUN contents and renal tissue nuclear cytokine κB p50 mRNA expression were significantly lower in the high,medium and low dose groups of Lithocarpus litseifoliu(P＜0.01,P＜0.05).The UA levels were significantly lower in the high dose group of Lithocarpus litseifoliu(P＜0.05),and renal ABCG2 mRNA expression was significantly higher in the medium dose group(P＜0.01).The renal URAT1 mRNA expression was significantly decreased in the low dose group(P＜0.01).Conclusion Lithocarpus litseifoliu has shown ameliorative effects on HN mice,and the mechanism may be related to the modulation of renal uric acid transporters,improvement of renal function and anti-inflammation effects.

AIM To investigate the consistency of chemical constituents between formula granules and standard decoction of Coptidis Rhizoma.METHODS Eighteen batches of standard decoctions were prepared,after which the extraction rate and contents,transfer rates of magnolflorine,jatrorrhizine,columbamine,epiberberine,coptisine,palmatine,berberin were determined,HPLC characteristic chromatograms were established.RESULTS There were 11 common peaks in the characteristic chromatograms of 18 batches of standard decoctions and 24 batches of formula granules with the similarities of 0.861-1.000,which were clusterd into two categories.The formula granules and standard decoction demonstrated approximated extraction rate and contents,transfer rates of index constituents.CONCLUSION The chemical constituents between formula granules and standard decoction of Coptidis Rhizoma display good consistency,which can provide references for the quality control,process research and clinical application of the former.

Objective: To describe the distribution characteristics of hypertension among adult twins in the Chinese National Twin Registry (CNTR) and to provide clues for exploring the role of genetic and environmental factors on hypertension. Methods: A total of 69 220 (34 610 pairs) of twins aged 18 and above with hypertension information were selected from CNTR registered from 2010 to 2018. Random effect models were used to describe the population and regional distribution of hypertension in twins. To estimate the heritability, the concordance rates of hypertension were calculated and compared between monozygotic twins (MZ) and dizygotic twins (DZ). Results: The age of all participants was (34.1±12.4) years. The overall self-reported prevalence of hypertension was 3.8%(2 610/69 220). Twin pairs who were older, living in urban areas, married, overweight or obese, current smokers or ex-smokers, and current drinkers or abstainers had a higher self-reported prevalence of hypertension (P<0.05). Analysis within the same-sex twin pairs found that the concordance rate of hypertension was 43.2% in MZ and 27.0% in DZ, and the difference was statistically significant (P<0.001). The heritability of hypertension was 22.1% (95%CI: 16.3%- 28.0%). Stratified by gender, age, and region, the concordance rate of hypertension in MZ was still higher than that in DZ. The heritability of hypertension was higher in female participants. Conclusions: There were differences in the distribution of hypertension among twins with different demographic and regional characteristics. It is indicated that genetic factors play a crucial role in hypertension in different genders, ages, and regions, while the magnitude of genetic effects may vary.
Adult ; Female ; Humans ; Male ; Alcohol Drinking ; Diseases in Twins/genetics* ; Hypertension/genetics* ; Twins, Dizygotic/genetics* ; Twins, Monozygotic/genetics*

Objective: To describe the distribution characteristics of hyperlipidemia in adult twins in the Chinese National Twin Registry (CNTR) and explore the effect of genetic and environmental factors on hyperlipidemia. Methods: Twins recruited from the CNTR in 11 project areas across China were included in the study. A total of 69 130 (34 565 pairs) of adult twins with complete information on hyperlipidemia were selected for analysis. The random effect model was used to characterize the population and regional distribution of hyperlipidemia among twins. The concordance rates of hyperlipidemia were calculated in monozygotic twins (MZ) and dizygotic twins (DZ), respectively, to estimate the heritability. Results: The age of all participants was (34.2±12.4) years. This study's prevalence of hyperlipidemia was 1.3% (895/69 130). Twin pairs who were men, older, living in urban areas, married,had junior college degree or above, overweight, obese, insufficient physical activity, current smokers, ex-smokers, current drinkers, and ex-drinkers had a higher prevalence of hyperlipidemia (P<0.05). In within-pair analysis, the concordance rate of hyperlipidemia was 29.1% (118/405) in MZ and 18.1% (57/315) in DZ, and the difference was statistically significant (P<0.05). Stratified by gender, age, and region, the concordance rate of hyperlipidemia in MZ was still higher than that in DZ. Further, in within-same-sex twin pair analyses, the heritability of hyperlipidemia was 13.04% (95%CI: 2.61%-23.47%) in the northern group and 18.59% (95%CI: 4.43%-32.74%) in the female group, respectively. Conclusions: Adult twins were included in this study and were found to have a lower prevalence of hyperlipidemia than in the general population study, with population and regional differences. Genetic factors influence hyperlipidemia, but the genetic effect may vary with gender and area.
Adult ; Female ; Humans ; Male ; Middle Aged ; Young Adult ; China/epidemiology* ; Diseases in Twins/genetics* ; Hyperlipidemias/genetics* ; Metabolic Diseases ; Twins, Dizygotic ; Twins, Monozygotic/genetics*

Because the brain and kidneys share a common basis for small vessel lesions, the related research on cerebral microbleeds (CMBs) in patients with chronic kidney disease (CKD) is gradually increasing. The development of neuroimaging technology has significantly increased the detection rate of CMBs, but there is still controversy over whether CKD will increase the incidence of CMBs. This article reviews the relationship between CKD and CMBs, pathogenesis, biomarkers, and treatment.