1.Survey on frequency of medical X-ray diagnosis in Heilongjiang province
Yu ZHAO ; Yi ZHANG ; Ruichong WANG ; Xin ZHANG ; Wenjia ZHANG ; Pengchao HU
Chinese Journal of Radiological Medicine and Protection 2019;39(5):338-343
Objective To investigate the total examinations of conventional X-ray diagnosis and CT diagnosis of radiation diagnosis and treatment institutions,in order to explore the distribution characteristic of radiological diagnosis frequency and diagnostic patients,and to estimate the application frequency of medical X-ray diagnosis in Heilongjiang province.Methods The questionnaire was sent to all radiation diagnosis and treatment institutions in forms of public document issued by the administrative department of health and family planning of Heilongjiang province.Basic situations and patient numbers of conventional X-ray diagnosis (interventional diagnosis not included) and CT diagnosis in 2016 were collected and summarized combined with sampled on-site verification.The application frequency of medical X-ray diagnosis was obtained using permanent resident population in Heilongjiang province in 2016.Results Totally 1 645 medical radiation institutions were investigated,including 81 tertiary hospitals,359 secondary hospitals,808 primary hospitals or unrated medical institutions,and 397 private dental clinics.The examinations of conventional X-ray diagnosis and CT diagnosis were 7 706 050 and 7 063 734,respectively.The application frequency of conventional X-ray diagnosis and CT diagnosis was 200.9 and 184.1 examinations per 1 000 population,respectively,and varied from 98.0 to 274.7 in different areas.The ratio of examinations in public medical institutions to that in private medical institutions was 7.47 ∶ 1.Conclusions 50% of the total radiological diagnosis were made in tertiary hospitals,and only 13% were made in medical institutions below primary in Heilongjiang.Meanwhile,although the number of public and private medical institutions was at the same scale,the total examination of radiological diagnosis in public medical institutions was 7 times of that in private medical institutions.The application frequency of conventional X-ray diagnosis and CT diagnosis in Heilongjiang province in 2016 was similar to that of Jiangsu province in 2015.
2.The study of ureteral decellularized matrix coating induced the differentiation of adipose-derived stem cells
Pengchao WANG ; Shuwei XIAO ; Weijun FU ; Xu ZHANG
Chinese Journal of Urology 2020;41(9):692-697
Objective:To investigate the effect of ureteral decellularized matrix (UDM) coating on the differentiation of adipose stem cells.Methods:From January 2018 to October 2019, UDM was prepared by perfusion method. H&E staining, DAPI staining, and DNA quantification were used to assessment the residues of cellular component in UDM and normal ureter; Masson′s trichrome staining and collagen quantification evaluated the collagen retention in UDM and normal ureter; the distribution and content of glycosaminoglycan in UDM and normal ureter were analyzed through Alcian Blue staining and glycosaminoglycan quantification. Canine adipose mesenchymal stem cells (cADMSCs) were isolated and cultured and identified by flow cytometry. The UDM was digested by pepsin enzyme to prepare the decellularized matrix coating as the experimental group. Type Ⅰ rat tail collagen coating was used as a control group. The cADMSCs were seeded on different coatings, and the differentiation of the cADMSCs was detected by immunofluorescence staining and Western Blot.Results:H&E and DAPI staining showed that the nuclear residue was not observed in the UDM. The DNA quantification demonstrated that the DNA content in UDM [(38.87±3.40) ng/mg] was significantly lower than that in the normal ureter group [(1 694.63±169.83) ng/mg, P<0.05]. Masson′s trichrome staining and collagen quantification confirmed that the collagen content in UDM [(265.89 ± 16.40) μg/mg] was no significantly different from the normal ureter group [(288.73 ± 16.32) μg/mg, P>0.05]. Alcian Blue staining showed the distribution of glycosaminoglycan in the UDM, and glycosaminoglycan quantification suggested that the content of glycosaminoglycan in the UDM [(1.57 ± 0.19) μg/mg] was lower than that in the normal ureter group [(3.43 ± 0.12) μg/mg] ( P<0.05). Immunofluorescence staining and Western Blot confirmed that the expression of Alpha-smooth muscle Actin (α-SMA) in the experimental group (2.51 ± 0.27, 3.68 ± 0.33, 4.91 ± 0.45) was higher than that in the control group (0.97±0.09, 1.02 ± 0.10, 1.00 ± 0.11) at 3 d, 7 d, 10 d ( P<0.05). The expression of α-SMA in the experimental group increased gradually with culture time ( P<0.05). While no changing of α-SMA expression in the control group was recordered. Conclusions:The prepared UDM removed the cellular components, and retained the collagen structure and bioactive components well; the ureter decellularized matrix coating could promote the differentiation of cADMSCs to smooth muscle cells.
3.The study on the tissue engineered bladder patch constructed with the double-layer silk scaffold and adipose-derived stem cells for bladder repair and reconstruction
Shuwei XIAO ; Weijun FU ; Pengchao WANG ; Jian ZHAO ; Zhengyun LING ; Ziyan AN ; Zhouyang FU ; Xu ZHANG
Chinese Journal of Urology 2022;43(10):778-785
Objective:To investigate the effect of tissue engineered bladder patch constructed by double-layer silk scaffold and adipose-derived stem cells (ADSCs) in the repair and reconstruction of bladder.Methods:This study was conducted from May 2020 to March 2021. The silk fibroin (SF) aqueous solution was obtained from silkworm cocoons, and a double-layer silk scaffold composed of silk fibroin film and silk fibroin sponge was further prepared. The rat ADSCs were isolated, cultured, and the ADSCs surface markers (CD29, CD90, CD45, CD106) were identified by flow cytometry. The ADSCs were planted on a double-layer silk scaffold to construct a tissue-engineered bladder patch. Thirty-six male SD rats were randomly divided into three groups: tissue engineered bladder patch group (SF-ADSCs group, n=15), double-layer silk scaffold group (SF group, n=15), control group ( n=6). The tissue engineered bladder patch (SF-ADSCs group) and double-layer silk scaffold (SF group) were wrapped on the omentum to promote vascularization. The vascularization was evaluated by HE and immunofluorescence staining. The wrapped tissue engineered bladder patch and double-layer silk scaffold were used to repair the defective bladder. In the control group (six rats), the incision was closed immediately after the bladder tissue fully exposed. At 4 weeks and 12 weeks after operation, the general morphology of bladder tissue and cystography were performed to evaluate the recovery of bladder morphology. After the graft was harvested, HE and Masson's trichrome staining and immunofluorescence staining were used to observe the regeneration of bladder wall tissue. Urodynamics was used to assess the recovery of bladder function at 12 weeks after operation. Results:The flow cytometry results confirmed that the isolated cells positively expressed CD29 and CD90, and there was no significant expression of CD45 and CD106. Gross observation and scanning electron microscope confirmed that the preparation of double-layer silk scaffold not only had a pore structure that was conducive to cell planting, but also had good toughness and was facilitated to surgical suture. The number (43.50±2.66) and area (0.73±0.03)% of vascular-like structures in the SF-ADSCs group after the omentum encapsulation was significantly higher than that in the SF group [(24.50±3.51), (0.55±0.05)%], and the difference was statistically significant ( P<0.05). At 4 weeks after bladder repair, the histological staining of the grafts in the SF-ADSCs and SF groups showed a large number of degraded fragments of double-layer silk scaffold. At 12 weeks, the morphology of the graft in the SF-ADSCs group showed uniform bladder morphology, which was similar to that of normal bladder tissue. Immunofluorescence staining showed that the continuous urothelial layer, abundant smooth muscle tissue, vascular structure and regenerated neurons could be observed in the SF-ADSCs group. Urodynamic test showed that the bladder maximum volume (0.74±0.03)ml and compliance (16.68±0.44)μl/cm H 2O in the SF-ADSCs group, which were better than that in the SF group [(0.47±0.05)ml, (14.89±0.37)μl/cm H 2O], but lower than that in the control group [(1.12±0.08)ml, (19.34±0.45)μl/cm H 2O], and the difference was statistically significant ( P<0.05). Conclusions:The tissue engineered bladder patch constructed with double-layer silk scaffolds and ADSCs could promote the morphological repair of bladder tissue, the regeneration of bladder wall structure and the recovery of bladder physiological function.
4.The study of the whole bladder acellular matrix prepared by the perfusion decellularization system combined with the adipose-derived stem cells to construct the tissue engineering bladder
Shuwei XIAO ; Weijun FU ; Pengchao WANG ; Jian ZHAO ; Zhengyun LING ; Ziyan AN ; Zhouyang FU ; Xu ZHANG
Chinese Journal of Urology 2023;44(3):211-217
Objective:To prepare the whole bladder acellular matrix (BAM) using the self-designed perfusion decellularization system, and evaluate the feasibility of constructing the tissue engineering bladder with the adipose-derived stem cells (ADSCs).Methods:This study was conducted from October 2020 to April 2021. The self-designed perfusion decellularization system was used, and four different decellularization protocols (group A, group B, group C and group D) were formulated, according to the flow direction of the perfusate and the action time of different decellularization solutions. Among them, the urethral orifice of the bladder tissue was used as the outflow tract of the perfusion fluid in groups A and B. The top of the bladder was cut off and used as the outflow tract of the perfusion fluid in groups C and D. In groups A and C, 1% Triton X-100 was treated for 6 h, and 1% sodium dodecyl sulfate (SDS) was treated for 2 h. In groups B and D, 1% Triton X-100 was treated for 7 h, and 1% sodium dodecyl sulfate (SDS) was treated for 1 h. In addition, the tissue in the normal bladder group was directly obtained from the natural bladder tissue, which did not require perfusion, cryopreservation and thawing. The fast and efficient decellularization protocol was screened out through HE, DAPI, Masson trichrome and Alcian Blue staining and quantitative analyses to prepare the whole bladder scaffold. The prepared BAM was used as the scaffold material, and the ADSCs were used as the seeding cells to construct the tissue engineering bladder. HE and DAPI staining were used to observe the distribution of ADSCs on the BAM.Results:HE and DAPI staining showed that there was no obvious nuclear residue in the group C. Masson trichrome and Alcian Blue staining showed that the collagen structure and glycosaminoglycan were well preserved in the group C. There was no significant difference in bladder wall thickness between the group C and the normal bladder group [(975.44±158.62)μm vs.(1 064.49±168.52)μm, P > 0.05]. The DNA content in the group C [(43.59 ±4.59) ng/mg] was lower than that in the normal bladder group, group A, group B and group D [(532.50±26.69), (135.17±6.99), (182.49±13.69) and(84.00±4.38)ng/mg], and the difference was statistically significant ( P<0.05). The collagen content [(10.98 ± 0.29)μg/mg] and glycosaminoglycan content [(2.30±0.18)μg/mg] in group C were not significantly different with those in the normal bladder group [(11.69±0.49) and (2.36±0.09)μg/mg, P>0.05]. Scanning electron microscopy showed that a large number of pore structures could be observed on the surface of the prepared BAM in groups A-D and were facilitated to cell adhesion. The isolated and cultured ADSCs were identified by flow cytometry to confirm the positive expression of CD90 and CD29, and the negative expression of CD45 and CD106. Live/dead staining and CCK-8 detection confirmed that the prepared BAM in the group C had no cytotoxicity. HE and DAPI staining showed that a large number of ADSCs were distributed on the surface and inside of the tissue engineering bladder. Conclusions:The whole bladder shape BAM prepared by the self-designed perfusion decellularization system could be used as the scaffold material for bladder tissue engineering, and the constructed tissue engineering bladder could be used for bladder repair and reconstruction.
5.Efficacy and safety of curcumin in the treatment of knee osteoarthritis: a systematic review
Shichang JI ; Rongrong CHEN ; Pengchao SONG ; Bingjie LIU ; Huiqin HAO ; Junfeng ZHANG
Chinese Journal of Rheumatology 2022;26(4):250-257,C4-2
Objective:To analyze the efficacy and safety of curcumin in the treatment of knee osteoarthritis.Methods:The randomized controlled trials of curcumin in the treatment of knee osteoarthritis published from January 2011 to August 2021 were retrieved. The bias risk of the included literatures was evaluated by Revman 5.3 software, and the efficacy related indexes and the incidence of adverse events were analyzed by Stata 16.0 software. The weighted mean difference ( WMD) was calculated for the difference of efficacy indexes, the odds ratio ( OR) was calculated for the difference of safety indexes, the difference was compared by t test. Results:① A total of 9 relevant literatures were included, all of which were in English. ② A total of 724 patients were included in the study, of which 383 were treated with curcumin capsules and 341 were treated with placebo. ③ The visual analogue scale/score (VAS) of patients treated with oral curcumin at 3-4, 6 and 8 weeks were significantly lower than those of patients treated with oral placebo, the differences were statistically significant [weighted mean difference ( WMD)=-1.09, 95% CI (-1.44, -0.73), P<0.001; WMD=-1.52, 95% CI (-2.35, -0.69), P<0.001; WMD=-1.20, 95% CI(-1.71, -0.69), P<0.001]. ④ The western Ontario and McMaster universities osteoarthritis index (WOMAC) scores of patients treated with oral curcumin for 3-4 and 6-8 weeks were significantly lower than those of patients treated with oral placebo, and the differences were statistically significant [ WMD=-7.96, 95% CI(-14.89, -1.04), P=0.020; WMD=-15.34, 95% CI(-20.51, -10.18), P<0.001]. Specifically, the WOMAC pain and stiffness scores of patients treated with oral curcumin for 6-8 weeks were significantly lower than those of patients treated with oral placebo, and the differences were statistically significant [ WMD=-2.16, 95% CI(-3.69, -0.63), P=0.010; WMD=-1.00, 95% CI (-1.54, -0.46), P<0.001]. The WOMAC joint function scores of patients treated with oral curcumin for 3-4 and 6-8 weeks were significantly lower than those of patients treated with oral placebo, the difference was statistically significant [ WMD=-3.21, 95% CI(-4.51, -1.92), P<0.001; WMD=-7.07, 95% CI(-11.19, -2.94), P<0.001]. ⑤ There was no significant difference in the incidence of adverse events between oral curcumin and placebo [ OR=1.19, 95% P(0.74, 1.90), P=0.478]. Conclusion:Compared with placebo, oral curcumin can significantly alleviate the pain, stiffness and joint function of patients with knee osteoarthritis, and its safety is similar to placebo.
6.Changes of insulin secretion and its signal transduction mechanism at early stage of severe scald in rats
Bohan ZHANG ; Chuan′an SHEN ; Pengchao SUN ; Bo ZHENG ; Dawei LI ; Zhaoxing LIU ; Shengbo XU ; Jiachen SUN ; Wen ZHANG
Chinese Journal of Burns 2020;36(4):280-287
Objective:To observe the changes of insulin secretion in the early stage of severe scald in rats, and to explore its signal transduction mechanism.Methods:Twenty-four male Wistar rats aged 7 weeks were divided into sham injury alone (SIA) group, sham injury+ BPV (HOpic) (SIB) group, scald alone (SA) group, and scald+ BPV (HOpic) (SB) group using the random number table, with 6 rats in each group. Full-thickness scald of 50% total body surface area was inflicted in rats of SA and SB groups by a 6-s immersion of the abdomen and a 12-s immersion of the back in 94 ℃ hot water. Rats in SIA and SIB groups received sham injuries through immersion of the back and abdomen in 37 ℃ warm water for 6 and 12 seconds respectively. From 0 (immediately) to 2 day (s) after injury, the rats in groups SB and SIB were intraperitoneally injected with the phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) signaling pathway enhancer BPV (HOpic) solution (0.5 mg/mL) at the dosage of 0.6 mg/kg once a day, and the rats in groups SA and SIA were intraperitoneally injected with the same volume of dimethyl sulfoxide once a day. At post injury hour (PIH) 72, the tail blood of rats was sampled for measuring fasting blood glucose (FBG) with a glucometer, and the pancreatic tissue samples of rats was harvested for observing the pathological manifestations of islets by hematoxylin-eosin staining, counting the docked granules per 10 μm membrane of islet beta cells and calculating the proportion of insulin vesicles through the observation of the ultrastructure of islet beta cells by transmission electron microscope, and detecting the phosphorylation level of Akt in the pancreatic PI3K/Akt signaling pathway by Western blotting. Data were statistically analyzed with one-way analysis of variance and least significant difference test.Results:(1) At PIH 72, the rat FBG levels in SIA and SIB groups were normal and similar ( P>0.05). Compared with the levels of those two groups, the rat FBG level in SA group was increased significantly ( P<0.01), while the level in SB group showed no obvious change ( P>0.05). Compared with that in SA group, the rat FBG level in SB group was decreased significantly ( P<0.01). (2) At PIH 72, the morphology of rat islets was complete and the islet cells distributed regularly in SIA and SIB groups. Compared with those in SIA and SIB groups, the morphology of rat islets was incomplete, the insulin vesicles in islets were common, the islet cells distributed irregularly, and the cytoplasm of some islet beta cells was lightly stained or translucent in SA group; the morphology of islets in SB group did not change obviously. Compared with those in SA group, the morphology of islets was comparatively complete, the insulin vesicles in islets were less common, the islet cells distributed comparatively regularly, and the lightly stained or translucent cytoplasm of islet beta cells was less in SB group. (3) At PIH 72, the number of docked granules per 10 μm membrane of rat islet beta cells and the proportion of insulin vesicles in SIA and SIB groups were similar ( P>0.05). Compared with those in SIA and SIB groups, the number of docked granules per 10 μm membrane of rat islet beta cells in SA group was decreased significantly ( P<0.01), while the proportion of insulin vesicles was increased significantly ( P<0.01); the number of docked granules per 10 μm membrane of rat islet beta cells in SB group was obviously decreased ( P<0.05), while the proportion of insulin vesicles did not change obviously ( P>0.05). Compared with those in SA group, the number of docked granules per 10 μm membrane of rat islet beta cells in SB group was significantly increased ( P<0.01), while the proportion of insulin vesicles was significantly decreased ( P<0.01). (4) At PIH 72, the phosphorylation levels of Akt in SIA, SIB, SA, and SB groups were 0.91±0.03, 0.98±0.03, 0.78±0.08, and 0.87±0.08, respectively. Compared with that in SIA group, the phosphorylation level of Akt was increased obviously in SIB group ( P<0.05) but was decreased significantly in SA group ( P<0.01), while the level in SB group did not change obviously ( P>0.05). Compared with the level in SIB group, the phosphorylation levels of Akt in SA and SB groups were decreased significantly ( P<0.01). Compared with that in SA group, the phosphorylation level of Akt in SB group was increased significantly ( P<0.05). Conclusions:At the early stage post severe scald in rats, the activity of the pancreatic PI3K/Akt signaling pathway and the function of insulin secretion are reduced. Improving the activity of the pancreatic PI3K/Akt signaling pathway in rats can ameliorate the function of insulin secretion and recover the physiological level of blood glucose.
7.Development of an immunochromatographic strip for detection of antibodies against porcine reproductive and respiratory syndrome virus.
Huawei LI ; Jifei YANG ; Dengke BAO ; Jie HOU ; Yubao ZHI ; Yanyan YANG ; Pengchao JI ; Enmin ZHOU ; Songlin QIAO ; Gaiping ZHANG
Journal of Veterinary Science 2017;18(3):307-316
A simple and rapid immunochromatographic test strip incorporating a colloidal gold-labeled recombinant Nsp7 antigen probe was successfully developed for the detection of anti-porcine reproductive and respiratory syndrome virus (PRRSV) antibodies in swine. Recombinant Nsp7 protein of PRRSV labeled with colloidal gold was dispensed on a conjugate pad for use as the detector. Staphylococcal protein A and purified porcine anti-Nsp7 antibodies were blotted on a nitrocellulose membrane to form test and control lines, respectively. A comparison of the strip with standard diagnostic tests, enzyme-linked immunosorbent assays and immunoperoxidase monolayer assay, was also performed. The immunochromatographic test strip was shown to be of high specificity and sensitivity. Furthermore, the strip assay is rapid and easy to perform with no requirement for professional-level skills or equipment. It is suggested that the immunochromatographic test strip can be used to quickly and accurately detect PRRSV antibody and to be suitable for diagnostic purposes in the field.
Antibodies*
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Collodion
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Colloids
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Diagnostic Tests, Routine
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Enzyme-Linked Immunosorbent Assay
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Gold Colloid
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Immunochromatography
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Membranes
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Porcine Reproductive and Respiratory Syndrome*
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Porcine respiratory and reproductive syndrome virus*
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Sensitivity and Specificity
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Staphylococcal Protein A
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Swine
8.Progress of biomarkers in liver cancer
Yuyuan ZHANG ; Zhen LI ; Pengchao ZHAN ; Xin LI ; Shuwen YE ; Caihong WANG ; Yang LIU
Journal of International Oncology 2021;48(4):241-245
With the development of detection methods, various biomarkers of liver cancer have been detected constantly, which is of great significance for the early diagnosis and real-time monitoring of liver cancer after treatment. Based on the differences in the sensitivity and specificity of different biomarkers, exploration of the value of diverse biomarkers in the diagnosis and prognosis assessment of liver cancer can provide an important reference for clinicians to scientific and rational application of distinct biomarkers.
9.Honokiol,an SIRT3 activator,alleviates postoperative cognitive dysfunc-tion via inhibiting hippocampal neuronal ferroptosis in mice
Tao HUANG ; Tiantian HAN ; Qianqian XU ; Zhen ZHANG ; Pengchao HU ; Xudong DING ; Huiyu LUO ; Lian ZENG
Chinese Journal of Pathophysiology 2024;40(5):827-835
AIM:To investigate the impact of honokiol(HKL),an activator of silent information regulator 3(SIRT3),on postoperative cognitive dysfunction(POCD)in mice,and to explore the potential mechanisms.METHODS:Ten-month-old male C57/BL6 mice were randomly divided into control(Con)group,surgical(Sur)group and Sur+HKL group(n=10).The mice in Sur+HKL group were intraperitoneally injected with HKL for 7 d before modeling.The mice in Sur and Sur+HKL groups underwent tibial fracture open reduction and internal fixation to establish the POCD model.The assessment of cognitive function was conducted using the open-field test(OFT),novel object recognition test(NORT),Morris water maze test(MWMT),and Y-maze test(YMT).Nissl staining was employed to assess the morphology,struc-ture and vitality of hippocampal and cortical neurons in mice.The protein expression of glutathione peroxidase 4(GPX4),solute carrier family 7 member 11(SLC7A11),acyl coenzyme A synthetase long-chain family member 4(ACSL4),SIRT3 and nuclear factor E2-related factor 2(NRF2)in the mouse hippocampus was detected by Western blot,while im-munofluorescence staining was utilized to determine GPX4 level in mouse neurons.RESULTS:No statistically signifi-cant differences were observed among the groups in terms of total distance moved and central zone exploration during the OFT(P>0.05).However,the results from the NORT and YMT indicated that the mice in Sur group exhibited significant-ly lower recognition indexes,reduced alternation rates(P<0.01),and decreased percentages of entries and crossing time into the new arm after side arm blockade(P<0.01),when compared with Con group.Furthermore,the mice in Sur group demonstrated a slower decrease in latency during the learning period of MWMT,while significantly lower latency,fewer crossing number and lower percentage of time in the target quadrant were observed during the testing period of MWMT(P<0.01).The above indicators were obviously enhanced in Sur+HKL group compared with Sur group(P<0.01).The results of Nissl staining indicated lighter neuronal staining in the hippocampal CA1 region and medial prefrontal cortex in Sur group,accompanied by a significant reduction in the number of Nissl-stained positive neurons(P<0.01).Notably,HKL pretreatment demonstrated a significant improvement in neuronal vitality.Analysis of Western blot revealed that compared with Con group,the expression of SIRT3,GPX4,SLC7A11 and NRF2 in Sur group was significantly reduced,while the expression of ACSL4 was significantly increased(P<0.05).However,these alterations were reversed after treatment with HKL(P<0.05).Immunofluorescence staining of hippocampal neurons corroborated the findings from Western blot analy-sis,demonstrating a notable decrease in GPX4 expression in hippocampal neurons of Sur group,which was significantly restored after HKL pretreatment(P<0.01).CONCLUSION:Treatment with HKL attenuates POCD in mice,potentially through its inhibitory effect on hippocampal neuronal ferroptosis.
10.Clinical data combined with CT radiomics features for evaluating programmed cell death-ligand 1 status in gastric cancer
Qinglong LI ; Pengchao ZHAN ; Jingjing XING ; Xing LIU ; Pan LIANG ; Yonggao ZHANG ; Jianbo GAO
Chinese Journal of Medical Imaging Technology 2024;40(9):1371-1376
Objective To observe the value of clinical data combined with CT radiomics features for evaluating programmed cell death-ligand 1(PD-L1)status in gastric cancer.Methods Totally 277 gastric cancer patients were retrospectively enrolled and randomly divided into training set(n=195)and validation set(n=82)at the ratio of 7:3.There were 88 cases in PD-L1 positive subgroup and 107 cases in negative subgroup of training set,while 37 and 45 cases of validation set,respectively.The clinical and conventional CT features were compared between subgroups in both sets,the independent influencing factors of PD-L1 status in gastric cancer were analyzed,and radiomic features were screened based on CT data.Then clinical model,radiomics model and clinical-radiomics model were established,and the efficacy of each model for evaluating PD-L1 status in gastric cancer was observed.Results In training set,Borrmann type,cN stage,cM stage,clinical stage,maximum diameter and thickness were significant difference between subgroups(all P<0.05).Borrmann type,clinical stage and the thickness were all independent influencing factors of PD-L1 positivity(all P<0.05).The area under the curve(AUC)of clinical model,radiomic model and clinical-radiomics model for evaluating PD-L1 status in gastric cancer in training set was 0.748,0.832 and 0.841,respectively,and was 0.657,0.801 and 0.789 in validation set,respectively.AUC of clinical model was lower than the other models(all P<0.05).Conclusion Clinical data combined with CT radiomics features was helpful for evaluating PD-L1 status in gastric cancer.