Influence of the initial recurrence site on prognosis after radical surgery for colorectal cancer: a retrospective cohort study.

BACKGROUND & AIMS: In this retrospective study, we aimed to elucidate how the initial recurrence site influences the post-recurrence survival (PRS) after the curative resection of colorectal cancer. PATIENTS AND METHODS: We collected samples from patients with stage I-III colorectal adenocarcinoma who were admitted to Yunnan Cancer Hospital from January 2008 to December 2019. Four hundred and six patients who developed recurrence after radical resection were included. The cases were classified according to the original site of recurrence as follows: liver metastases (n = 98), lung metastases (n = 127), peritoneum (n = 32), other individual organ (n = 69), two or more organs or sites (n = 49), and local recurrence (n = 31). Kaplan-Meier survival curves were used to compare the PRS of patients with different initial sites of recurrence. The influence of the initial recurrence site on PRS was analyzed using the Cox proportional hazards model. RESULTS: The 3-year PRS of simple liver metastasis was 54.04% (95% CI, 45.46%-64.24%), and the 3-year PRS of simple lung metastasis was 50.05% (95% CI, 42.50%-58.95%). No significant difference was observed between simple liver metastasis or simple lung metastasis and local recurrence with a 3-year PRS of 66.99% (95% CI, 53.23%-84.32%). The 3-year PRS for peritoneal metastases was 25.43% (95% CI, 14.76%-43.82%), and the 3-year PRS for two or more organ sites was 34.84% (95% CI, 24.16%-50.24%). The peritoneal (hazard ratio [HR], 1.75; 95% CI, 1.10-2.79; P = 0.0189) and metastasis to two or more organs or sites (HR, 1.59; 95% CI, 1.05-2.43; P = 0.0304) were PRS-independent adverse prognostic factors. CONCLUSION: The prognosis of patients with peritoneum and multiple organs or sites recurred was poor. This study suggests early monitoring of peritoneal and multiple organ or site recurrence after surgery. This part of patients should receive comprehensive treatment as early as possible to improve their prognosis.

Reflective Fiber Temperature Probe Based on Localized Surface Plasmon Resonance towards Low-Cost and Wireless Interrogation.

Reflection fiber temperature sensors functionalized with plasmonic nanocomposite material using intensity-based modulation are demonstrated for the first time. Characteristic temperature optical response of the reflective fiber sensor is experimentally tested using Au-incorporated nanocomposite thin films deposited on the fiber tip, and theoretically validated using a thin-film-optic-based optical waveguide model. By optimizing the Au concentration in a dielectric matrix, Au nanoparticles (NP) exhibit a localized surface plasmon resonance (LSPR) absorption band in a visible wavelength that shows a temperature sensitivity ~0.025%/°C as a result of electron-electron and electron-phonon scattering of Au NP and the surrounding matrix. Detailed optical material properties of the on-fiber sensor film are characterized using scanning electron microscopy (SEM) and focused-ion beam (FIB)-assisted transmission electron microscopy (TEM). Airy's expression of transmission and reflection using complex optical constants of layered media is used to model the reflective optical waveguide. A low-cost wireless interrogator based on a photodiode transimpedance-amplifier (TIA) circuit with a low-pass filter is designed to integrate with the sensor. The converted analog voltage is wirelessly transmitted via 2.4 GHz Serial Peripheral Interface (SPI) protocols. Feasibility is demonstrated for portable, remotely interrogated next-generation fiber optic temperature sensors with future capability for monitoring additional parameters of interest.

Modest stabilization by most hydrogen-bonded side-chain interactions in membrane proteins.

Understanding the energetics of molecular interactions is fundamental to all of the central quests of structural biology including structure prediction and design, mapping evolutionary pathways, learning how mutations cause disease, drug design, and relating structure to function. Hydrogen-bonding is widely regarded as an important force in a membrane environment because of the low dielectric constant of membranes and a lack of competition from water. Indeed, polar residue substitutions are the most common disease-causing mutations in membrane proteins. Because of limited structural information and technical challenges, however, there have been few quantitative tests of hydrogen-bond strength in the context of large membrane proteins. Here we show, by using a double-mutant cycle analysis, that the average contribution of eight interhelical side-chain hydrogen-bonding interactions throughout bacteriorhodopsin is only 0.6 kcal mol(-1). In agreement with these experiments, we find that 4% of polar atoms in the non-polar core regions of membrane proteins have no hydrogen-bond partner and the lengths of buried hydrogen bonds in soluble proteins and membrane protein transmembrane regions are statistically identical. Our results indicate that most hydrogen-bond interactions in membrane proteins are only modestly stabilizing. Weak hydrogen-bonding should be reflected in considerations of membrane protein folding, dynamics, design, evolution and function.

Similar energetic contributions of packing in the core of membrane and water-soluble proteins.

A major driving force for water-soluble protein folding is the hydrophobic effect, but membrane proteins cannot make use of this stabilizing contribution in the apolar core of the bilayer. It has been proposed that membrane proteins compensate by packing more efficiently. We therefore investigated packing contributions experimentally by observing the energetic and structural consequences of cavity creating mutations in the core of a membrane protein. We observed little difference in the packing energetics of water and membrane soluble proteins. Our results imply that other mechanisms are employed to stabilize the structure of membrane proteins.

Pharmacodynamic Substances and Action Mechanisms of Chaihu Shugansan in Antidepressant Treatment： A Review / 中国实验方剂学杂志

Depression is a kind of complex mental illness， which is mainly treated by western medicine at present， but the effect of western antidepressant drugs is not good due to the combined influence of side effects and individual differences of patients. Depression is a "stagnation syndrome" in traditional Chinese medicine， and its treatment principle is to disperse stagnated liver Qi for relieving Qi stagnation. The classic traditional Chinese medicine formula Chaihu Shugansan （CHSGS） has a long history of treating depression and demonstrates significant therapeutic efficacy. Clinically， the addition and subtraction of CHSGS is flexible， but the properties of the active ingredients are vague， and the mechanism and function are unclear. In order to elucidate the pharmacodynamic basis and antidepressant mechanism of CHSGS， this article reviews the pharmacodynamic material basis of CHSGS， clinical research and antidepressant mechanism research progress. Clinically， CHSGS can treat various types of depression such as primary depression， post-stroke depression， and postpartum depression. This article summarizes 32 main ingredients of CHSGS， among which albiflorin， ferulic acid， naringin， hesperidin， saikosaponin a， glycyrrhetinic acid， tangeretin， meranzin hydrate， nobiletin and glycyrrhizic acid are the quality markers （Q-markers） for the antidepressant effect of CHSGS. The antidepressant mechanism of CHSGS is complex， including regulating monoamine neurotransmitters， hypothalamic-pituitary-adrenal （HPA） axis， neurotrophic factors， inflammatory response， cell damage-related pathways， oxidative stress， etc. This article helps to deeply understand the pharmacodynamic basis and mechanism of CHSGS in treating depression， and provides a theoretical basis for the clinical application of CHSGS in treating depression and the development of antidepressant drugs.

Clinical features of children with coronavirus disease 2019 caused by Delta variant infection in different age groups / 中国当代儿科杂志

OBJECTIVES@#To study the clinical features of children with coronavirus disease 2019 (COVID-19) caused by Delta variant infection in different ages groups.@*METHODS@#A total of 45 children with COVID-19 caused by Delta variant infection who were hospitalized in the designated hospital in Henan Province, China, from November 17 to December 17, 2021, were included. They were divided into three groups: <6 years group (n=16), 6-13 years group (n=16), and >13 years group (n=13). The three groups were compared in clinical features and laboratory examination data.@*RESULTS@#COVID-19 in all age groups was mainly mild. Main manifestations included cough and expectoration in the three groups, and fever was only observed in the 6-13 years group. The <6 years group had significantly higher serum levels of aspartate aminotransferase, lactate dehydrogenase, and creatine kinase isoenzymes than the other two groups (P<0.05). The 6-13 years group had the highest proportion of children with elevated serum creatinine levels (50%). Among the three groups, only 4 children in the >13 years group had an increase in serum C-reactive protein levels. The 6-13 years group had the lowest counts of CD3+CD4+ lymphocytes, CD3+CD8+ lymphocytes, and natural killer cells in the peripheral blood among the three groups. The >13 years group had a significantly higher positive rate of SARS-CoV-2 IgG on admission than the other two groups (P<0.05). There was no significant difference in the imaging findings on chest CT among the three groups (P>0.05).@*CONCLUSIONS@#The clinical features of COVID-19 caused by Delta variant infection in children of different age groups may be different: children aged <6 years tend to develop myocardial injury, and those aged 6-13 years have fever except cough and expectoration and tend to develop renal and immune dysfunction.

Predictive value of MR myocardial strain in predicting recent adverse cardiovascular events after primary PCI in patients with acute ST-segment elevation myocardial infarction / 中华放射学杂志

Objective:To investigate the clinical application value of left ventricular myocardial strain obtained by cardiac MR (CMR) in recent major adverse cardiovascular events (MACE) in patients with acute ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI).Methods:From January 2020 to December 2020, a total of 163 patients successfully underwent primary PCI and underwent CMR examination within one week after surgery at Affiliated Hospital of Xuzhou Medical University. The scan sequences included rapid balance-fast field echo and late-gadolinium enhancement. CVI42 post-processing software was used to analyze and measure the left ventricular myocardial strain indices, including left ventricular global longitudinal strain (GLS), left ventricular global circumferential strain (GCS), and left ventricular global radial strain (GRS). According to the results of the 1-year follow-up after surgery, the patients were divided into the MACE group ( n=28) and the non-MACE group ( n=135). For continuous variables with a normal distribution, the t test of two independent samples was used for comparisons between groups. For continuous variables with an abnormal distribution, the variables were compared and analyzed by the rank sum test. For categorical variables, the χ 2 tests were used for between-group comparisons. Cox regression was used to analyze the prognostic value of myocardial strain on the development of MACE in patients with STEMI. The receiver operating characteristic (ROC) curve was used to analyze the diagnostic efficacy of myocardial strain parameters, and the optimal cut-off value was evaluated by calculating the Youden index. Results:The GLS, GCS, and GRS of the MACE group were (-10.4±3.3)%, [-11.9 (-14.5, -9.3)]%, and (18.3±6.3)%, respectively, and those of the non-MACE group were (-13.7±3.4)%, [-14.6 (-16.4, -11.7)]%, and (22.3±6.1)%, respectively. The difference between the two groups was statistically significant ( t/ Z=-4.71, -3.04, 3.21, P<0.05). Multivariate Cox regression analysis showed that GLS was an independent predictor of MACE (HR=1.546, 95%CI 1.180-2.027, P=0.002). The ROC curve analysis showed that GLS had the largest area under the curve (AUC) (AUC=0.754, 95%CI 0.658-0.851, P<0.001), with a cut-off value of -12.45%. Its diagnostic sensitivity was 71.4%, and the specificity was 67.4%. The value was better than that of the traditional predictor of STEMI prognosis, namely, left ventricular ejection fraction (AUC=0.680, 95%CI 0.567-0.793, P=0.003). Conclusion:GLS of CMR is an independent predictor of MACE in STEMI patients undergoing primary PCI.

Effect of multi-glycosides of Tripterygium wilfordii on renal injury in diabetic kidney disease rats through NLRP3/caspase-1/GSDMD pyroptosis pathway / 中国中药杂志

This study investigated the effect of multi-glycosides of Tripterygium wilfordii(GTW) on renal injury in diabetic kidney disease(DKD) rats through Nod-like receptor protein 3(NLRP3)/cysteine-aspartic acid protease-1(caspase-1)/gsdermin D(GSDMD) pyroptosis pathway and the mechanism. To be specific, a total of 40 male SD rats were randomized into the normal group(n=8) and modeling group(n=34). In the modeling group, a high-sugar and high-fat diet and one-time intraperitoneal injection of streptozotocin(STZ) were used to induce DKD in rats. After successful modeling, they were randomly classified into model group, valsartan(Diovan) group, and GTW group. Normal group and model group were given normal saline, and the valsartan group and GTW group received(ig) valsartan and GTW, respectively, for 6 weeks. Blood urea nitrogen(BUN), serum creatinine(Scr), alanine ami-notransferase(ALT), albumin(ALB), and 24 hours urinary total protein(24 h-UTP) were determined by biochemical tests. The pathological changes of renal tissue were observed based on hematoxylin and eosin(HE) staining. Serum levels of interleukin-1β(IL-1β) and interleukin-18(IL-18) were detected by enzyme-linked immunosorbent assay(ELISA). Western blot was used to detect the expression of pyroptosis pathway-related proteins in renal tissue, and RT-PCR to determine the expression of pyroptosis pathway-related genes in renal tissue. Compared with the normal group, the model group showed high levels of BUN, Scr, ALT, and 24 h-UTP and serum levels of IL-1β and IL-18(P<0.01), low level of ALB(P<0.01), severe pathological damage to kidney, and high protein and mRNA levels of NLRP3, caspase-1, and GSDMD in renal tissue(P<0.01). Compared with the model group, valsartan group and GTW group had low levels of BUN, Scr, ALT, and 24 h-UTP and serum levels of IL-1β and IL-18(P<0.01), high level of ALB(P<0.01), alleviation of the pathological damage to the kidney, and low protein and mRNA levels of NLRP3, caspase-1, and GSDMD in renal tissue(P<0.01 or P<0.05). GTW may inhibit pyroptosis by decreasing the expression of NLRP3/caspase-1/GSDMD in renal tissue, thereby relieving the inflammatory response of DKD rats and the pathological injury of kidney.

On-Site Assessment of a Cryogenic Disinfectant for the Alpine Environment and Outer Packaging of Frozen Items / 生物医学与环境科学（英文）

OBJECTIVE@#To study the effectiveness and feasibility of cryogenic disinfectants in different cold scenarios and analyze the key points of on-site cryogenic disinfection.@*METHODS@#Qingdao and Suifenhe were selected as application sites for the manual or mechanical spraying of cryogenic disinfectants. The same amount of disinfectant (3,000 mg/L) was applied on cold chain food packaging, cold chain containers, transport vehicles, alpine environments, and article surfaces. The killing log value of the cryogenic disinfectant against the indicator microorganisms ( Staphylococcus aureus and Escherichia coli) was used to evaluate the on-site disinfection effect.@*RESULTS@#When using 3,000 mg/L with an action time of 10 min on the ground in alpine regions, the surface of frozen items, cold-chain containers, and cold chain food packaging in supermarkets, all external surfaces were successfully disinfected, with a pass rate of 100%. The disinfection pass rates for cold chain food packaging and cold chain transport vehicles of centralized supervised warehouses and food processing enterprises were 12.5% (15/120), 81.67% (49/60), and 93.33% (14/15), respectively; yet, the surfaces were not fully sprayed.@*CONCLUSION@#Cryogenic disinfectants are effective in disinfecting alpine environments and the outer packaging of frozen items. The application of cryogenic disinfectants should be regulated to ensure that they cover all surfaces of the disinfected object, thus ensuring effective cryogenic disinfection.

Predictive value of systemic immune-inflammation index and sdLDL-C for contrast-induced acute kidney injury in patients with ST-segment elevation myocardial infarction undergoing emergency percutaneous coronary intervention / 中华检验医学杂志

Objective:To explore the predictive value of systemic immune-inflammation index (SII) and small and dense low-density lipoprotein-cholesterol (sdLDL-C) on contrast-induced acute kidney injury (CI-AKI) in patients with acute ST-segment elevation myocardial infarction (STEMI) undergoing emergency percutaneous coronary intervention (PCI).Methods:This retrospective analysis included 674 STEMI patients who underwent emergency PCI in Affiliated Hospital of Xuzhou Medical University from November 2019 to October 2021, all patients were divided into a training cohort ( n=450) and validation cohort ( n=224) at a ratio of 2∶1 according to the chronological sequence. The patients in the training cohort were further divided into CI-AKI group ( n=92) and non-CI-AKI group ( n=358). Information at admission and emergency blood biochemical indexes were collected, and the SII was calculated. Multifactorial logistic regression analysis was used to explore the independent factors influencing the occurrence of CI-AKI in STEMI patients undergoing emergency PCI in the training cohort and a predictive model was established. Receiver operating characteristic (ROC) curve and Hosmer-Lemeshow test were used to evaluate the model discrimination and calibration. Results:The prevalence of CI-AKI was 20.4% (92/450). Age, proportion of women, sdLDL-C, urea, baseline creatinine, uric acid, neutrophil count, neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR) and SII were significantly higher in the CI-AKI group than in the non-CI-AKI group (all P<0.05), and left ventricular ejection fraction (LVEF), high-density lipoprotein cholesterol, estimated glomerular filtration rate (eGFR) and lymphocyte count were significantly lower in the CI-AKI group than in the non-CI-AKI group (all P<0.05). The results of multifactorial logistic regression analysis showed that age ( OR=1.046, P=0.001), LVEF ( OR=0.916, P<0.001), sdLDL-C ( OR=4.754, P<0.001), uric acid ( OR=1.012, P=0.007), eGFR ( OR=0.994, P=0.002), and lnSII ( OR=2.471, P<0.001) were independent determinants of CI-AKI after emergency PCI in STEMI patients. ROC curve analysis showed that area under the curve (AUC) for the diagnosis of CI-AKI was 0.688 with a sensitivity of 73.9% and specificity of 61.5% for the SII cut-off point of 1 179.07×10 9/L. The AUC for the diagnosis of CI-AKI was 0.709 with a sensitivity of 65.2% and specificity of 77.4% for the sdLDL-C cut-off point of 1.147 mmol/L. The AUC for the diagnosis of CI-AKI was 0.847 with a sensitivity of 88.0% and a specificity of 70.6% for the combination of SII and sdLDL-C with age, LVEF, uric acid and eGFR. The Hosmer-Lemeshow test (χ2=6.913, P=0.546) proved the goodness of fit of the model. Conclusions:SII and sdLDL-C have significant clinical value in the prediction of CI-AKI. SII and sdLDL-C combined with age, LVEF, uric acid and eGFR could further improve the predictive efficacy of CI-AKI.

Clinical features of children with coronavirus disease 2019 Delta variant infection after vaccination with inactivated SARS-CoV-2 vaccine / 中国当代儿科杂志

OBJECTIVES@#To study the clinical features of children with coronavirus disease 2019 (COVID-19) Delta variant infection vaccinated or not vaccinated with inactivated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine.@*METHODS@#A total of 11 children with COVID-19 Delta variant infection who were vaccinated with inactivated SARS-CoV-2 vaccine and were hospitalized in the designated hospital in Henan Province, China, from November 3 to December 17, 2021 were enrolled as the vaccinated group. Thirty-one children with COVID-19 Delta variant infection who were not vaccinated and were hospitalized during the same period were enrolled as the unvaccinated group. A retrospective analysis was performed on their epidemiological data, clinical features, and laboratory examination results.@*RESULTS@#There was no significant difference in gender composition and disease classification between the two groups (P>0.05), and there was also no significant difference in the incidence rates of the clinical symptoms such as cough, expectoration, and fever between the two groups (P>0.05). No significant difference was found between the two groups in leukocyte count, lymphocyte percentage, alanine aminotransferase, and serum creatinine (P>0.05). Compared with the unvaccinated group, the vaccinated group had significantly lower levels of aspartate aminotransferase, lactate dehydrogenase, and creatine kinase-MB (P<0.05). There was no significant difference between the two groups in the proportion of children with elevated C-reactive protein or procalcitonin and the levels of peripheral blood cytokines (P>0.05). The vaccinated group had significantly lower counts of B lymphocytes and total T lymphocytes (CD3+) than the unvaccinated group (P<0.05). Compared with the unvaccinated group, the vaccinated group had a significantly higher positive rate of IgG on admission and at week 2 of the course of disease (P<0.05), as well as a significantly higher Ct value of nucleic acid at weeks 1 and 2 of the course of disease (P<0.05).@*CONCLUSIONS@#Vaccination with inactivated SARS-CoV-2 vaccine may reduce myocardial injury caused by SARS-CoV-2 Delta variant. For children with SARS-CoV-2 Delta variant infection after the vaccination, more attention should be paid to their immune function.

Evaluation of the effect of comprehensive prevention and management of diabetes mellitus of two cross-sectional surveys based on community population / 中华预防医学杂志

To investigate the prevalence of diabetes mellitus (DM) among residents in Chongchuan district, Nantong city in 2012 and 2018, and evaluate the effectiveness of community comprehensive management of DM. Based on the data of 17 780 and 13 382 residents in the cross-sectional surveys of the " National Demonstration Area for Comprehensive Prevention and Control of Chronic Diseases " project in Chongchuan District of Nantong City, Jiangsu Province in 2012 and 2018, 4 583 and 3 996 DM-related information were obtained. The population of Jiangsu Province in 2012 and 2018 was used as the reference for standardization. The rates of prevalence and management (including awareness, treatment, treatment of patients who knew their diabetic situation, control and control of patients under treatment) of DM in the two surveys were compared using chi-square test. The results showed that in 2012 and 2018, the prevalence rates of DM were 12.0% and 15.7% (χ²=24.25, P<0.05), and the standardized rates were 10.1% and 10.8% (χ²=1.05, P=0.306). The incidence rates were 5.7% and 2.3%, respectively (χ²=55.60, P<0.05). The standardized prevalence rates in the two surveys were 9.7% and 11.6% for males (χ²=3.66, P=0.056) and 10.5% and 9.9% for females (χ²=0.50, P=0.481), 7.2% and 6.5% (χ²=0.85, P=0.357) for people aged 18-59 years old and 20.6% and 21.9% (χ²=0.91, P=0.339) for people aged 60 years and over, respectively. The standardized rates of awareness, treatment, treatment of patients who knew their diabetic situation, control, and control of patients under treatment in 2018 were 84.4%, 80.3%, 95.2%, 58.4%, and 70.2%, respectively, higher than 47.2%, 23.4%, 44.8%, 30.4% and 59.4% in 2012 (χ²=183.33, χ²=380.65, χ²=282.99, χ²=93.24, χ²=6.22, all P<0.05). Among men, the standardized rates of awareness, treatment, treatment of patients who knew their diabetic situation, and control in 2018 were 85.8%, 78.8%, 91.8% and 62.7%, higher than 50.5%, 37.5%, 72.3% and 32.6% in 2012 (χ²=78.40, χ²=96.17, χ²=27.55, χ²=48.96, all P<0.05). Similarly, the standardized management rates in 2018 were 83.0%, 81.7%, 98.5%, 54.1% and 65.1%, higher than 44.0%, 10.0%, 18.3%, 28.2% and 48.8% in 2012 among women (χ²=105.52, χ²=326.36, χ²=317.22, χ²=43.34, χ²=3.87, all P<0.05). The standardized rates of awareness, treatment, treatment of patients who knew their diabetic situation, and control of people aged 18-59 and 60 years and over were 82.9%, 79.7%, 96.1%, 55.0% and 88.0%, 81.8%, 93.0% and 67.2%, higher than 42.6%, 19.8%, 42.2%, 27.5% and 63.9%, 36.8%, 53.9%, 40.8% in 2012 (χ²=44.51, χ²=102.17, χ²=57.78, χ²=21.65, all P<0.05; χ²=71.18, χ²=181.55, χ²=146.26, χ²=59.23, all P<0.05). The comprehensive prevention and control system of chronic diseases, which comprehensively covered the life of community residents, had good management effect on DM, and effectively promoted health education and health promotion.

[Tissue culture and rapid propagation of Trichosanthes kirilowii].

OBJECTIVE: To study tissue culture of Trichosanthes kirilowii, and establish the technique of rapid propagation. METHODS: Cluster buds were induced from stem tip and stem with axillary bud, calluses were induced from stems and leaves. RESULTS: Cluster buds could be induced on both the bud and axillary bud from 2-years-old tuber of Trichosanthes kirilowii with MS medium containing 2 mg/L BA and 0.5 -0.05 mg/L NAA. The roots could be induced with MS + 0.1 mg/L NAA + 0.2 mg/L IBA. The seedling with roots could be transplanted after domestication, and achieved the rapid seedling propagation. Calluses could be induced from the stems and leaves with MS + 4 mg/L BA + 0.5 mg/L NAA, and the calluses then could be differentiated into seedlings without root. CONCLUSION: The male and female seedlings of Trichosanthes kirilowii can be propagated largely using stem tip or axillary bud in short period. The technique of rapid propagation on Trichosanthes kirilowii have a high benefit and low costs.

Role and mechanism of stabilizing microtubules of endothelial cells and pericytes in improving the microvasculature dysfunction after spinal cord injury / 解剖学报

Objective To explore the role and mechanism of stabilizing microtubules of endothelial cells and pericytes for ameliorating the dysfunction of microvasculature after spinal cord injury(SCI). Methods The endothelial cells and pericytes from rat brain microvascular tissue (microvessel) were separated and subjected to glucose oxygen deprivation (OGD). The cell viability was detected by CCK-8 and the expression of α-tubulin was detected by immunofluorescence and Western blotting. Rats (n = 36) were subjected to dorsal spinal cord transection at T

Acid-base metabolism variants in infarct core and penumbra using amide proton transfer weighted imaging in subacute cerebral infarction / 中华放射学杂志

Objective:To assess the value of amide proton transfer weighted (APTw) imaging in the evaluation of pH changes in infarct core (IC) and ischemic penumbra (IP) in subacute cerebral infarction.Methods:The data of twenty-three subacute cerebral infarction patients with unilateral steno-occlusive disease of the middle cerebral artery (subacute infarction group) from April to November 2019 in the First Affiliated Hospital of Dalian Medical University were prospectively analyzed. Fifteen healthy volunteers were enrolled in this study as the control group. All subjects underwent conventional MRI, DWI, 3D-pseudo continuous arterial spin labeling (3D-pCASL) and APTw sequences. Based on DWI images, relative cerebral blood flow (rCBF) and APTw images to determine the region of IC, blood flow penumbra [cerebral blood flow(CBF)-DWI mismatch area, IP CBF] and metabolic penumbra (APTw-DWI mismatched area, IP APT). 3D ROIs were used to semi-automatically measure the APTw signals and the volume of IC and IP CBF of the patients in subacute infarction group. The comparison of APTw signals between the infarct side and the contralateral side in the subacute infarction group, the comparison of bilateral APTw signals in the control group, and the comparison of APTw signals in the IC and IP CBF regions were performed by paired-sample t test or Wilcoxon signed-rank test. The paired-sample t test or Mann-Whitney U test was used to compare the APTw signals between the two groups. The Friedman test was applied to compare the difference of volumes among IP CBF1.5, IP CBF2.5 and IP APT . Results:There was no significant difference of the APTw signals among the IC, the contralateral side in the subacute infarction group and the control group ( P>0.05). The APTw signals of IP CBF and IC of the infarction group were statistically different ( P<0.05). Compared with the contralateral side of IP CBF1.5 (3.7±1.7, -1.84±1.48, 5.57±2.75), the APTwmax (3.07±1.41, t=-3.012, P=0.006), APTw min [-1.30 (-1.74, -0.57), Z=-2.099, P=0.036], and APTwmax-min(4.51±2.58, t=-3.273, P=0.003) signals in the IP CBF1.5 were decreased ( P<0.05). Compared with the contralateral side of IP CBF2.5 [-1.53 (-2.80, -0.91), 5.31±2.61], the APTw min [-1.08 (-1.60, -0.49), Z=-2.616, P=0.009] and APTwmax-min (4.41±2.72, t=-3.228, P=0.004) signals in the IP CBF2.5 were decreased. The volumes of IP CBF1.5 [107.51(50.08, 138.61)mm 3], IP APT [99.00 (53.27, 121.335) mm 3] and IP CBF2.5 [89.91 (51.53, 139.87) mm 3] were successively reduced (χ2=7.913, P=0.019), and the volume of IP CBF2.5 was significantly smaller than that of IP CBF1.5 ( P=0.037). Conclusion:The acid-base metabolism in the IC of subacute cerebral infarction is not obvious, but the blood flow penumbra has local acid-base metabolism imbalance, and the range of metabolic penumbra coincides with the blood flow penumbra.

Immunogenicity of Whole / 生物医学与环境科学（英文）

Objectives@#To evaluate the immunogenicity of @*Methods@#Protein extracts from @*Results@#Immunization with @*Conclusion@#This is the advanced study to investigate the immunogenicity of

Side-chain contributions to membrane protein structure and stability.

The molecular forces that stabilize membrane protein structure are poorly understood. To investigate these forces we introduced alanine substitutions at 24 positions in the B helix of bacteriorhodopsin and examined their effects on structure and stability. Although most of the results can be rationalized in terms of the folded structure, there are a number of surprises. (1) We find a remarkably high frequency of stabilizing mutations (17%), indicating that membrane proteins are not highly optimized for stability. (2) Helix B is kinked, with the kink centered around Pro50. The P50A mutation has no effect on stability, however, and a crystal structure reveals that the helix remains bent, indicating that tertiary contacts dominate in the distortion of this helix. (3) We find that the protein is stabilized by about 1kcal/mol for every 38A(2) of surface area buried, which is quite similar to soluble proteins in spite of their dramatically different environments. (4) We find little energetic difference, on average, in the burial of apolar surface or polar surface area, implying that van der Waals packing is the dominant force that drives membrane protein folding.

Proline substitutions are not easily accommodated in a membrane protein.

Proline residues are relatively common in transmembrane helices. This suggests that proline substitutions may be readily tolerated in membrane proteins, even though they invariably produce deviations from canonical helical structure. We have experimentally tested this possibility by making proline substitutions at 15 positions throughout the N-terminal half of bacteriorhodopsin helix B. We find that six of the substitutions yielded no active protein and all the others were destabilizing. Three mutations were only slightly destabilizing, however, reducing stability by about 0.5 kcal/mol, and these all occurred close to the N terminus. This result is consistent with the observation that proline is more common near the ends of TM helices. To learn how proline side-chains could be structurally accommodated at different locations in the helix, we solved the structures of a moderately destabilized mutant positioned near the N terminus of the helix, K41P, and a severely destabilized mutant positioned near the middle of the helix, A51P. The K41P mutation produced only local structural alterations, while the A51P mutation resulted in small, but widely distributed structural changes in helix B. Our results indicate that proline is not easily accommodated in transmembrane helices and that the tolerance to proline substitution is dependent, in a complex way, on the position in the structure.

Magnetic resonance hyperintense vessel sign: clinical significance and related factors / 中华神经科杂志

Objective:To investigate clinical significance and related factors of magnetic resonance hyperintense vessel sign (HVS).Methods:The clinical data and related imaging parameters of 109 patients with acute anterior circulation occlusion cerebral infarction, who admitted to Northern Theater Command General Hospital of People′s Liberation Army from April 2017 to August 2019, were analyzed retrospectively. Brain magnetic resonance imaging (MRI) examinations including fluid attenuated inversion recovery (FLAIR), diffusion weighted imaging (DWI) and three dimensional time of flight magnetic resonance angiography (3D TOF MRA) sequences within 24 hours of onset were performed. According to the distribution range of HVS in FLAIR sequence, the patients were divided into four grades (0, 1, 2 and 3), grades 0 and 1 belonging to HVS low grade group, and grades 2 and 3 HVS high grade group. Univariate and multivariate analyses were made to explore related factors of HVS. Fifty-two patients who completed baseline CT within six hours of onset before MRI examination were performed CT-Alberta Stroke Program Early CT Score (CT-ASPECTS) and DWI-Alberta Stroke Program Early CT Score (DWI-ASPECTS).The difference between CT-ASPECTS and DWI-ASPECTS was calculated. When the difference of ASPECTS ≤1, they were categorized as ASPECTS unchanged group (AN group); when the difference of ASPECTS>1, they were categorized as ASPECTS changed group (AY group). These two groups were compared to explore whether there was any difference in HVS grade, and Spearman correlation analysis was performed to investigate the relationship between HVS grade and the difference of ASPECTS.Results:The difference of hyperlipidemia, TOAST classification (large artery atherosclerosis (LAA), other etiology (SOE) or undetermined etiology (SUE)) and Willis circle classification (types Ⅰ, Ⅱ, Ⅲ and Ⅳ) between HVS groups were remarkable (58.6% (34/58) vs 37.3% (19/51), χ2=4.959, P=0.026; 23/5/23 vs 43/1/14, P=0.004; 3/14/12/22 vs 7/29/14/8, χ2=13.124, P=0.004). Other clinical factors and the locations of vessel occlusion did not show significant difference ( P>0.05). Multivariate Logistic regression analysis indicated that LAA in TOAST classification (LAA vs SOE or SUE, OR=3.054, 95% CI1.257-7.422, P=0.014), Willis circle type Ⅰ (type Ⅰ vs type Ⅳ, OR=5.494, 95% CI1.074-28.091, P=0.041), and type Ⅱ (type Ⅱ vs type Ⅳ, OR=5.571, 95% CI1.895-16.372, P=0.002) were independent related factors to stimulate wide distribution of HVS. The grades of HVS were significantly different between the AN group and the AY group (1/15 vs18/18, χ2=9.114, P=0.002). Spearman correlation analysis showed that HVS grade was negatively correlated with the difference of ASPECTS ( r=-0.573, P<0.001). Conclusions:Both TOAST and Willis circle classifications are crucial factors affecting HVS distribution. HVS distribution range reflects the status of collateral compensatory. Recognizing HVS may help to evaluate the progress of early cerebral infarction volume.

Lexiscan can open the blood-brain barrier temporarily and reversibly / 中华核医学与分子影像杂志

Objective To evaluate the opening level and optimal time window of the blood-brain barrier induced by adenosine A2 receptor agonist ( Lexiscan) via dynamic enhanced MRI. Methods Twen-ty New Zealand white rabbits were divided into experiment group ( group A, n=10) and control group ( group B, n=10) . Rabbits in group A were injected with Lexiscan and rabbits in group B were injected with physiological salt via ear vein, then the coronary scanning was performed. Contrast enhanced MRI was performed at different time points ( 5, 10, 15, 20 min, and then every 10 min, until 2 h) following the in-fusion of Gd-diethylene triamine pentaacetic acid (DTPA). The signal intensity (SI) of region of interest ( ROI) was measured and the percent enhancement of SI was calculated. Evens blue staining results in brain tissues were observed. Pair t test was used to analyze the data. Results The percent enhancement of SI in group A significantly increased to (40. 93±3.70)％ at 5 min, reached the maximum of (43.03±3.62)％ at 30 min, slowly decreased until 50 min, and got to a stable level at almost 80 min. At each time point, the per-cent enhancement of SI in group A was significantly higher than that in group B ( t values:6.88-20.28, all P<0. 05) . The staining was evident in group A. Conclusions Lexiscan can open blood-brain barrier tem-porarily and reversibly, and the optimal opening time window is 10-50 min post-injection.