Comparison of resistive index and shear-wave elastography in the evaluation of chronic kidney allograft dysfunction

BACKGROUND Detection of early chronic changes in the kidney allograft is important for timely intervention and long-term survival.Conventional and novel ultrasound-based investigations are being increasingly used for this purpose with variable results.AIM To compare the diagnostic performance of resistive index(RI)and shear wave elastography(SWE)in the diagnosis of chronic fibrosing changes of kidney allograft with histopathological results.METHODS This is a cross-sectional and comparative study.A total of 154 kidney transplant recipients were included in this study,which was conducted at the Departments of Transplantation and Radiology,Sindh Institute of Urology and Transplantation,Karachi,Pakistan,from August 2022 to February 2023.All consecutive patients with increased serum creatinine levels and reduced glomerular filtration rate(GFR)after three months of transplantation were enrolled in this study.SWE and RI were performed and the findings of these were evaluated against the kidney allograft biopsy results to determine their diagnostic utility.RESULTS The mean age of all patients was 35.32±11.08 years.Among these,126(81.8%)were males and 28(18.2%)were females.The mean serum creatinine in all patients was 2.86±1.68 mg/dL and the mean estimated GFR was 35.38±17.27 mL/min/1.73 m2.Kidney allograft biopsy results showed chronic changes in 55(37.66%)biopsies.The sensitivity,specificity,positive predictive value(PPV),and negative predictive value(NPV)of SWE for the detection of chronic allograft damage were 93.10%,96.87%%,94.73%,and 95.87%,respectively,and the diagnostic accuracy was 95.45%.For RI,the sensitivity,specificity,PPV,and NPV were 76.92%,83.33%,70.17%,and 87.62%,respectively,and the diagnostic accuracy was 81.16%.CONCLUSION The results from this study show that SWE is more sensitive and specific as compared to RI in the evaluation of chronic allograft damage.It can be of great help during the routine follow-up of kidney transplant recipients for screening and early detection of chronic changes and selecting patients for allograft biopsy.

Association between triglyceride-glucose index and colorectal polyps:A retrospective cross-sectional study

BACKGROUND Colorectal polyps(CPs)are frequently occurring abnormal growths in the colorectum,and are a primary precursor of colorectal cancer(CRC).The triglyceride-glucose(TyG)index is a novel marker that assesses metabolic health and insulin resistance,and has been linked to gastrointestinal cancers.AIM To investigate the potential association between the TyG index and CPs,as the relation between them has not been documented.METHODS A total of 2537 persons undergoing a routine health physical examination and colonoscopy at The First People's Hospital of Kunshan,Jiangsu Province,China,between January 2020 and December 2022 were included in this retrospective cross-sectional study.After excluding individuals who did not meet the eligibility criteria,descriptive statistics were used to compare characteristics between patients with and without CPs.Logistic regression analyses were conducted to determine the associations between the TyG index and the prevalence of CPs.The TyG index was calculated using the following formula:Ln[triglyceride(mg/dL)×glucose(mg/dL)/2].The presence and types of CPs was determined based on data from colonoscopy reports and pathology reports.RESULTS A nonlinear relation between the TyG index and the prevalence of CPs was identified,and exhibited a curvilinear pattern with a cut-off point of 2.31.A significant association was observed before the turning point,with an odds ratio(95% confidence interval)of 1.70(1.40,2.06),P<0.0001.However,the association between the TyG index and CPs was not significant after the cut-off point,with an odds ratio(95% confidence interval)of 0.57(0.27,1.23),P=0.1521.CONCLUSION Our study revealed a curvilinear association between the TyG index and CPs in Chinese individuals,suggesting its potential utility in developing colonoscopy screening strategies for preventing CRC.

Progress of Triglyceride Glucose Index in Lesion Severity and Prognosis of Acute Coronary Syndromes

Background: In response to the escalating burden of cardiovascular diseases (CVDs) worldwide, exacerbated by lifestyle changes and socioeconomic shifts, acute coronary syndromes (ACS) stand out as a leading cause of morbidity and mortality. The pivotal role of insulin resistance in the pathogenesis of atherosclerosis, independent of traditional risk factors, has garnered significant interest. Objective: This review aims to synthesize the recent advancements in the utilization of the triglyceride glucose index (TyG index) as a biomarker for assessing the severity and predicting the prognosis of ACS lesions. Methods: A systematic search was conducted across PubMed, Embase, and Scopus databases, incorporating keywords such as “triglyceride glucose index”, “TyG index”, “acute coronary syndrome”, “cardiovascular disease”, “insulin resistance”, “coronary artery calcification”, “SYNTAX score”, “Gensini score”, and “major adverse cardiac events”. Studies were included from the inception of each database up to July 2024. Selection criteria encompassed observational studies, case-control studies, and randomized controlled trials, with a particular emphasis on evaluating the diagnostic and prognostic value of the TyG index in patients with acute coronary syndromes. Ultimately, 46 publications met the inclusion criteria. Data extraction and quality assessment were performed in accordance with established guidelines. Results: Evidence suggests that the TyG index, reflecting insulin resistance, blood glucose, and lipid levels, is significantly associated with lesion severity in ACS, including coronary artery calcification, SYNTAX score, and Gensini score. Moreover, it demonstrates predictive power for major adverse cardiovascular events, underscoring its potential as a valuable tool in clinical decision-making. Conclusion: The review highlights the emerging role of the TyG index in the assessment and prognosis of ACS, advocating for its incorporation into clinical practice as a complement to existing diagnostic modalities. However, the establishment of standardized reference ranges and further validation across diverse populations are warranted to refine its applicability in personalized medicine. The interdisciplinary approach is essential to advance our understanding of the complex interplay between insulin resistance and cardiovascular disease, paving the way for the development of more effective prevention and treatment strategies.

Renal resistive index measurements by ultrasound in patients with liver cirrhosis:Magnitude and associations with renal dysfunction

BACKGROUND The hemodynamic alterations seen in liver cirrhosis lead to renal vasoconstriction,ultimately causing acute kidney injury(AKI).The renal resistive index(RRI)is the most common Doppler ultrasound variable for measuring intrarenal vascular resistance.AIM To evaluate the association of the RRI with AKI in patients with liver cirrhosis and to identify risk factors for high RRI.METHODS This was a prospective observational study,where RRI was measured using Doppler ultrasound in 200 consecutive hospitalized patients with cirrhosis.The association of RRI with AKI was studied.The receiver operating characteristic(ROC)curve analysis was utilized to determine discriminatory cut-offs of RRI for various AKI phenotypes.Multivariate analysis was conducted to determine the predictors of high RRI.RESULTS The mean patient age was 49.08±11.68 years,with the majority(79.5%)being male;the predominant etiology of cirrhosis was alcohol(39%).The mean RRI for the study cohort was 0.68±0.09,showing a progressive increase with higher Child-Pugh class of cirrhosis.Overall,AKI was present in 129(64.5%)patients.The mean RRI was significantly higher in patients with AKI compared to those without it(0.72±0.06 vs 0.60±0.08;P<0.001).A total of 82 patients(41%)had hepatorenal syndrome(HRS)-AKI,29(22.4%)had prerenal AKI(PRA),and 18(13.9%)had acute tubular necrosis(ATN)-AKI.The mean RRI was significantly higher in the ATN-AKI(0.80±0.02)and HRS-AKI(0.73±0.03)groups than in the PRA(0.63±0.07)and non-AKI(0.60±0.07)groups.RRI demonstrated excellent discriminatory ability in distinguishing ATN-AKI from non-ATN-AKI(area under ROC curve:93.9%).AKI emerged as an independent predictor of high RRI(adjusted odds ratio[OR]:11.52),and high RRI independently predicted mortality among AKI patients(adjusted OR:3.18).CONCLUSION In cirrhosis patients,RRI exhibited a significant association with AKI,effectively differentiated between AKI phenotypes,and predicted AKI mortality.

血清丝氨酸蛋白酶Corin联合子宫动脉多普勒血流评分对子痫前期的预测价值评价

目的探讨Corin联合子宫动脉RI、PI、S/D值对子痫前期的预测价值。方法选择2015年12月-2020年9月在兰州大学第二医院行常规产检并诊断为子痫前期的孕妇(55例);同期单胎健康孕妇为对照组(55例)。ELISA方法测定孕中期(16~24周),孕晚期(28~32周)血清Corin浓度,超声多普勒检测孕中、晚期子宫动脉RI、PI、S/D值。ROC曲线分析上述指标联合对妊娠中晚期孕妇发生子痫前期的预测价值。结果孕中、晚期血清Corin含量联合子宫动脉PI、RI、S/D值得到的联合预测概率作ROC曲线下面积分别为0.850、0.862,敏感度分别为80.1%、88.3%,特异度分别为82.6%、83.9%,明显高于各指标单独使用的预测作用。结论联合检测孕妇血清Corin可提高子宫动脉血流动力参数对子痫前期的预测价值。

Deferred revascularization in diabetic patient according to combined invasive functional and intravascular imaging data:A case report

BACKGROUND Invasive functional evaluation by fractional flow reserve(FFR)is considered as a gold standard for the evaluation of intermediate coronary stenosis.However,in patients with diabetes due to accelerated progression of atherosclerosis the outcome may be worse even in the presence of negative functional testing.CASE SUMMARY We present a case of 55-year-old male diabetic patient who was admitted for chest pain.Diagnostic coronary angiography disclosed 2 intermediate stenoses of the obtuse marginal branch with no evidence of restenosis on previously implanted stent.Patient undergone invasive functional testing of intermediate lesion with preserved FFR(0.88),low coronary flow reserve(1.2)and very high index of microvascular resistance(84).Due to discrepancy in invasive functional parameters,intravascular imaging with optical coherence tomography showed fibrotic stenoses without signs of thin-sup fibroatheroma.Because of the preserved FFR and no signs of vulnerable plaque,the interventional procedure was deferred and the patient continued with optimal medications.CONCLUSION Combined functional and anatomic imaging of intermediate coronary stenosis in diabetic patients represent comprehensive contemporary decision pathway in the management of the patients.

基于ESV-ERI-MCR评价的嘉陵江流域景观生态格局构建与优化

[目的]分析嘉陵江流域景观生态格局,旨在增强生态系统服务功能,稳固生态系统从而降低生态风险,为促进区域可持续发展提供科学依据。[方法]以长江上游重要生态屏障嘉陵江流域为研究区,基于动态当量的生态系统服务价值(ESV)评价结果识别生态源地,基于最优空间尺度的景观生态风险(ERI)评价结果确定生态阻力面,再结合最小累积阻力模型(MCR)提取的生态廊道构建生态网络。[结果](1)2005—2020年嘉陵江流域ESV呈北高南低格局和呈波动增长趋势。生态系统服务价值总计增加2.10×10~(10)元,林地贡献率最高(50%),依次为草地(25%)、耕地(14%)。(2)嘉陵江流域适宜分析粒度和幅度分别为150,750 m。2005—2020年ERI呈西北部高,中南部低格局和呈逐年降低趋势。(3)整个生态网络呈西北—东南向分布。共识别出生态源地11个,总面积36297.19 km^(2),潜在生态廊道365条,生态节点133个。其中,重要生态廊道47条,重要生态节点39个。(4)建设的重点生态保护区作为新增生态源地,为嘉陵江流域限制开发区域。新增道路型生态廊道6条,绿带型生态廊道3条,河流型生态廊道13条,生态节点24个。[结论]优化后嘉陵江流域生态网络密度增加,贯穿了全方位的生态源地,整体连通度得以提升。研究成果可为流域生态格局修复、生态保护策略和可持续发展提供新思路。

超声测定PI、RI、Vmax结合血清sE-cadherin、CYFRA21-1对乳腺癌良恶性及淋巴结转移的诊断价值

目的研究超声测定的搏动指数(PI)、血流阻力指数(RI)、最大血流值(Vmax)结合血清可溶性E-钙黏连蛋白(sE-cadherin)、细胞角蛋白19片段(CYFRA21-1)对乳腺癌良恶性及腋窝淋巴结转移的诊断价值。方法选择242例乳腺肿块女性患者,年龄43~67岁,平均年龄55.23岁;身体质量指数19.5~28.9 kg/m^(2),平均身体质量指数24.12 kg/m^(2);病程4~8个月,平均病程6.45个月;均为初次入院就诊。彩色多普勒超声仪测定PI、RI和Vmax,并在术前采集空腹外周血,酶联免疫吸附分析测定血清sE-cadherin和CYFRA21-1。根据病理组织诊断结果将患者分成乳腺癌组(n=132)和乳腺良性组(n=110),并将乳腺癌患者分成腋窝淋巴结转移组(n=74)和腋窝淋巴结未转移组(n=58)。单因素分析临床资料,Logistic回归分析乳腺癌发生和腋窝淋巴结转移的独立影响因素,通过受试者工作特性(ROC)曲线分析各指标及回归分析诊断效能。结果乳腺良恶性病变区分ROC曲线结果表明,PI临界值1.34,灵敏度为69.70%,特异度为70.91%,曲线下面积(AUC)为0.801[95%可信区间(CI)0.750~0.852];RI诊断的临界值为0.69,灵敏度为65.15%,特异度65.45%,AUC为0.762(95%CI 0.707~0.812);Vmax诊断的临界值为13.11 m/s,灵敏度为59.85%,特异度60.00%,AUC为0.627(95%CI 0.564~0.699);血清sE-cadherin诊断的临界值为24.18 ng/mL,灵敏度为62.88%,特异度58.18%,AUC为0.709(95%CI 0.645~0.771);血清CYFRA21-1诊断的临界值为9.55 g/mL,灵敏度为74.24%,特异度75.45%,AUC为0.817(95%CI 0.769~0.865)。将回归预测方程作为新变量P,在最佳临界切点时,回归分析灵敏度81.82%,特异度79.09%,AUC为0.867(95%CI 0.829~0.908),回归分析灵敏度显著高于各指标单独检测(P<0.05)。乳腺癌淋巴结转移分析ROC曲线结果表明,PI临界值1.58,灵敏度为79.73%,特异度为68.97%,AUC为0.815(95%CI 0.727~0.902);RI诊断的临界值为0.83,灵敏度为63.51%,特异度70.69%,AUC为0.701(95%CI 0.558~0.844);Vmax诊断的临界值为17.36 m/s,灵敏度为54.05%,特异度55.17%,AUC为0.516(95%CI 0.384~0.649);血清sE-cadherin诊断的临界值为34.52 ng/mL,灵敏度为82.43%,特异度60.34%,AUC为0.755(95%CI 0.653~0.856);血清CYFRA21-1诊断的临界值为13.10 g/mL,灵敏度为60.81%,特异度65.52%,AUC为0.563(95%CI 0.426~0.701)。将回归预测方程作为新变量P,在最佳临界切点时,回归分析灵敏度85.14%,特异度84.48%,AUC为0.893(95%CI 0.816~0.970),回归分析灵敏度显著高于各指标单独检测(P<0.05)。结论超声参数及血清sE-cadherin和CYFRA21-1在乳腺癌和腋窝淋巴结中异常表达,且PI、RI、Vmax和血清sE-cadherin、CYFRA21-1单独和Logistic回归分析可应用于乳腺恶性病变和淋巴结转移的预测和诊断。

RRI、CAR及SII与重症急性胰腺炎并发急性肾损伤的相关性分析

目的探讨肾血管阻力指数(RRI)、C-反应蛋白与白蛋白比值(CAR)及全身免疫炎症指数(SII)与重症急性胰腺炎并发急性肾损伤(AKI)的相关性。方法选取2020年7月—2022年8月于本院收治的合并AKI重症急性胰腺炎患者28例(AKI组)和未并发AKI重症急性胰腺炎患者64例(非AKI组),共计92例重症急性胰腺炎患者作为研究对象,并设立为观察组,同期选取46例健康体检者设立为对照组,对比RRI、CAR及SII指标。采用Logistic回归模型分析重症急性胰腺炎并发AKI的危险因素,并用ROC曲线模型评估RRI、CAR、SII预测AKI的AUC、敏感度、特异度。结果观察组RRI、CAR及SII均高于对照组,差异具有统计学意义(P<0.05)。AKI组RRI、CAR及SII均高于非AKI组,差异具有统计学意义(P<0.05)。Logistic回归模型分析显示,RRI、CAR、SII水平升高会对重症急性胰腺炎患者并发AKI产生影响因素,差异具有统计学意义(P<0.05)。受试者工作特征(ROC)曲线分析显示,RRI、CAR、SII及三项联合预测重症急性胰腺炎患者并发AKI的曲线下面积(AUC)分别为0.789、0.813、0.823、0.907(P<0.05),敏感度分别为57.10%、50.00%、64.30%、92.90%;特异度分别为98.40%、95.30%、90.60%、84.40%。结论RRI、CAR及SII在重症急性胰腺炎患者并发AKI中呈升高趋势,检测其变化可为预测AKI的发生提供参考。

UtA-PI、UtA-RI联合血清TNF-α、hCG在凶险性前置胎盘合并胎盘植入中的诊断价值

目的:探究子宫动脉搏动指数(ultrasound uterine artery pulsation index,UtA-PI)、子宫动脉阻力指数(uterine artery resistance index,UtA-RI)联合血清肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)、人绒毛膜促性腺激素(human chorionic gonadotrophin,hCG)在凶险性前置胎盘合并胎盘植入中的诊断价值。方法:选取2020年1月—2022年2月于阳春市人民医院进行检查并确诊为凶险性前置胎盘合并胎盘植入的52例孕妇为观察组,另选取52例同期来本院进行健康产检的正常孕妇作为对照组。所有孕妇均进行子宫动脉超声检查,记录并比较两组孕妇的UtA-PI、UtA-RI;采用酶联免疫法对两组孕妇的血清TNF-α、hCG水平进行测定,并采用受试者工作特征(receiver operating characteristic,ROC)曲线分析UtA-PI、UtA-RI、TNF-α、hCG单独及联合检测对孕妇凶险性前置胎盘合并胎盘植入的诊断价值。结果:观察组UtA-PI、UtA-RI水平明显低于对照组,差异有统计学意义(P<0.05)。观察组TNF-α、hCG水平均明显高于对照组,差异有统计学意义(P<0.05)。ROC曲线结果显示,UtA-PI、UtA-RI、TNF-α、hCG单独及联合检测诊断凶险性前置胎盘合并胎盘植入的曲线下面积(area under the curve,AUC)分别为0.812、0.816、0.957、0.833、0.992,诊断价值均较高,其中联合诊断价值最高。结论:采用UtA-PI、UtA-RI联合血清TNF-α、hCG检测可以提高对凶险性前置胎盘合并胎盘植入的诊断效能。

PI、RI 指数结合血清sFlt-1 在子宫肌瘤患者中的诊断作用

目的:探讨超声评价PI和RI结合sFlt-1诊断子宫肌瘤的临床价值。方法:选取2020年1月~2022年8月收治的150例,怀疑患有子宫腺肌病或子宫肌瘤患者作为研究对象,计算PI和RI指数,检测患者血清sFlt-1水平。Logistic回归模型结合ROC曲线评价各指标单独及联合检测对子宫肌瘤诊断的临床价值。结果:子宫肌瘤患者RI及PI参数值均显著低于子宫腺肌病患者,而血清sFlt-1表达水平升高(P<0.001)。子宫动脉超声、血清sFlt-1水平联合检测诊断效能高于单项检测(P<0.05)。结论:子宫动脉超声联合血清sFlt-1检查可提高子宫肌瘤患者诊断的灵敏度和特异性,对于子宫肌瘤患者诊断具有潜在应用价值。

Role of cystatin C and renal resistive index in assessment of renal function in patients with liver cirrhosis

AIM:To evaluate the clinical significance of cystatin C and renal resistive index for the determination of renal function in patients with liver cirrhosis.METHODS:We conducted a study of 63 patients with liver cirrhosis.A control group comprised of 30 age and gender-matched healthy persons.Serum cystatin C was determined in all study subjects and renal Doppler ultrasonography was made.Estimated glomerular filtration rate from serum creatinine(GFRCr)and cystatin C(GFRCys)was calculated.RESULTS:We confirmed significant differences in val-ues of cystatin C between patients with different stages of liver cirrhosis according to Child-Pugh(P=0.01),and a significant correlation with model of end stage liver disease(MELD)score(rs=0.527,P<0.001).More patients with decreased glomerular filtration rate were identified based on GFRCys than on GFRCr(P<0.001).Significantly higher renal resistive index was noted in Child-Pugh C than in A(P<0.001)and B stage(P=0.001).Also,a significant correlation between renal resistive index and MELD score was observed(rs=0.607,P<0.001).Renal resistive index correlated significantly with cystatin C(rs=0.283,P=0.028)and showed a negative correlation with GFRCys(rs=-0.31,P=0.016).CONCLUSION:Cystatin C may be a more reliable marker for assessment of liver insufficiency.Additionally,cystatin C and renal resistive index represent sensitive indicators of renal dysfunction in patients with liver cirrhosis.

Central retinal artery resistive index and optical coherence tomography in assessment of glaucoma progression

AIM: To assess the relation between central retinal artery(CRA) resistive index(RI) and retinal nerve fiber thickness measured by optical coherence tomography(OCT) in assessment of disease progress in cases of open angle glaucoma.METHODS: Twenty-three patients with diagnosed open angle glaucoma were included in this study. They were examined by colored duplex ultrasonography of CRA with estimation of RI of CRA and ophthalmic artery(OA)with estimation of CRA/OA RI ratio as well as OCT measurement of the average retinal nerve fiber layer(RNFL) thickness in order to assess the disease progress.RESULTS: There was strong inverse relation between the increased RI in CRA as well as the increased CRA/OA RI ratio and the decrease in average RNFL thickness in cases of open angle glaucoma.CONCLUSION: Assessment of CRA RI can indirectly assess the vascular changes associated with glaucoma and can assess the degree of retinal atrophy helping in evaluating prognosis thus guiding the choice of treatment.

The Relationship of Carotid Plaque, Intima Media Thickness (IMT), Resistivity Index (RI) and Pulsatility Index(PI) in Asian-Indian Patients with Acute Ischemic Stroke with and without Type2 DM

Aim: To determine the relationship of carotid plaque, intima media thickness (IMT), resistivity index (RI) and pulsatility index (PI) and prevalence of different risk factors with acute ischemic stroke and stroke subtypes in both diabetic and non-diabetic subjects. Materials and methods: 80 cases of acute ischemic strokes and 40 healthy controls were included in the study. The plaque, IMT, RI and PI were measured by carotid duplex ultrasound. Results: 31 subjects were Type 2 diabetic, 54 hypertensive while 25 were both diabetic and hypertensive. 23 cases (28.75%) had lacunar stroke (LACI), 32 (40%) stroke involving partial anterior circulation(PACI), 10(12.5%) stroke in posterior circulation (PACI) and 15(18.75%) stroke involving total anterior circulation(TACI) respectively. The mean IMT (0.88 ± 0.19mm), RI(0.76 ± 0.05) and PI(1.71 ± 0.19) of patients and mean IMT (0.6±0.09mm), RI (0.61 ± 0.06) and PI (1.53 ± 0.11) of controls were statistically significant (p-0.000). The mean values of IMT, PI and RI were significantly higher in diabetics (IMT-0.90 ± 0.16 VS 0.64 ± 0.11, p-0.013;PI-1.76 ± 0.20 VS 1.49 ± 0.09, P-0.000 and RI-0.76 ± 0.04 VS 0.59 ± 0.06, P-0.000) and similarly the mean values for IMT, PI and RI in hypertensives as compared to controls (IMT-0.88 ± 0.16 vs 0.65 ± 0.10, P-0.006;PI1.69 ± 0.18 vs 1.49 ± 0.09, P-0.000 and RI 0.76 ± 0.04 vs 0.59 ± 0.06, P-0.000). The mean IMT, PI and RI were increased significantly in smokers compared to controls (IMT-0.93 ± 0.20 vs 0.63 ± 0.06, P-0.000;PI-1.82 ± 0.22 vs 1.49 ± 0.09, P-0.000 and RI-0.77 ± 0.04 vs 0.59 ± 0.06, P-0.000). Type 3 plaque accounted for 27 (56.2%) cases and Type 2 plaque 12 (25%) cases. The total number of plaques in patients as compared to controls were significantly more (P-0.0034) and the mean plaque area was 46 mm2 for cases and 20 mm2 for control (P-0.0001). TACI was the most common type of ischemic stroke seen in DM (60%), HTN (66.6%) and smokers (66.7%). Plaques (73.3%), IMT (0.90 ± 0.12), PI(1.72 ± 0.14) and RI (0.76 ± 0.13) were more commonly associated with TACI subtype. On multivariate analysis using ANOVA, the mean PI was highly significant (0.000) in relation to types of plaque. Summary and Conclusions: IMT, RI, PI and plaque type are useful diagnostic parameters for acute ischemic stroke and its subtypes. They can be used as noninvasive tools for predicting and preventing ischemic stroke in smokers as well as subjects with DM and hypertension.

Contrasting Characteristics of Lodging Resistance in Two Super-Rice Hybrids Differing in Harvest Index

The“super rice”breeding program in China has been successful in developing high-yielding hybrids,including few with high harvest index values.However,there is limited information on the relationship between lodging resistance and harvest index,and the mechanisms underlying the relationship in super-rice hybrids.In this study,a two-year field experiment was conducted to compare lodging resistance and its related traits between two superrice hybrids differing in harvest index,i.e.,Guiliangyou 2(G2)with a high harvest index and Y-liangyou 1(Y1)with a typical harvest index of modern high-yielding rice varieties.Results showed that compared to Y1,G2 was lower in plant height due to its lower aboveground N uptake,and its higher stem breaking resistance(i.e.,lower stem breaking index)resulted from a lower stem height at its center of gravity.Consequently,G2 had a higher lodging resistance(i.e.,lower plant lodging index)than Y1.This study suggests that developing super-rice hybrids with high harvest index values is a possible way to achieve both high grain yield and strong lodging resistance in rice.

Numerical Simulation of the Influence of Pore Structure on Resistivity, Formation Factor and Cementation Index in Tight Sandstone

Tight sandstone,with severe diagenesis and complex pore structure,differs greatly from conventional sandstone in terms of rock electrical parameters.In subsurface rock electrical experiments,various electrical parameters are confounded and can only be analyzed qualitatively.The lack of quantitative analysis for each individual electrical parameter presents a challenge for the evaluation of oil and gas saturation in tight sandstone.Based on the 2D pore-throat model and the features of pore structure in the tight sandstone of the Penglaizhen and Shaximiao Formations in the upper and middle Jurassic of the Western Sichuan Depression,this paper presents 3D micro pore-throat models for three types of tight sandstone.It proposes a finite element-based rock electrical simulation method to analyze the influence of pore structure parameters,such as throat radius and throat tortuosity,on electrical parameters such as resistivity,formation factor,and cementation index quantitatively.The research revealed the following results:(1)Throats of tight sandstone usually have lamellar or curved lamellar shapes that are slender and narrow.The lamellar throat used in the proposed porethroat model is more consistent with the features of tight sandstone than the tubular throat used in the original model.(2)The throat determines the conductivity of tight sandstone.The throat parallel to the electric potential has the greatest influence on conductivity,and the throat perpendicular to the potential has the least influence.(3)In tight sandstone grades I to III,as the porosity decreases,the formation factor increases and the cementation index decreases.(4)The results of the rock electrical simulation are consistent with the results of the rock electrical experiment,which indicates that the proposed rock electrical simulation method of tight sandstone is effective and accurate.

Heterogeneity and non-linearity of ecosystem responses to climate change in the Qilian Mountains National Park, China

Ecosystem responses to climate change,particularly in arid environments,is an understudied topic.This study conducted a spatial analysis of ecosystem responses to short-term variability in temperature,precipitation,and solar radiation in the Qilian Mountains National Park,an arid mountainous region in Northwest China.We collected precipitation and temperature data from the National Science and Technology Infrastructure Platform,solar radiation data from the China Meteorological Forcing Dataset,and vegetation cover remote-sensing data from the Moderate Resolution Imaging Spectroradiometer.We used the vegetation sensitivity index to identify areas sensitive to climate change and to determine which climatic factors were significant in this regard.The findings revealed a high degree of heterogeneity and non-linearity of ecosystem responses to climate change.Four types of heterogeneity were identified:longitude,altitude,ecosystem,and climate disturbance.Furthermore,the characteristics of nonlinear ecosystem responses to climate change included:(1)inconsistency in the controlling climatic factors for the same ecosystems in different geographical settings;(2)the interaction between different climatic factors results in varying weights that affect ecosystem stability and makes them difficult to determine;and(3)the hysteresis effect of vegetation increases the uncertainty of ecosystem responses to climate change.The findings are significant because they highlight the complexity of ecosystem responses to climate change.Furthermore,the identification of areas that are particularly sensitive to climate change and the influencing factors has important implications for predicting and managing the impacts of climate change on ecosystems,which can help protect the stability of ecosystems in the Qilian Mountains National Park.

Screening of Drought Resistance Identification Indexes for Rice(Oryza sativa L.) Cultivars in Ningxia

The morphological characters, physiological characters, yield traits and yield per plant of total 49 rice cultivars from Ningxia were investigated under conditions of water stress and non-water stress so as to determine the relationship between each trait and yield per plant under water stress and the relationship between each relative character and drought resistance coefficient under water stress and non-water stress. The correlation, grey correlation, stepwise regression and path analyses showed that the tiller number per plant, plant height, grain density, effective panicle number per plant and grain number per panicle, total 5 traits, were significantly correlated with the drought resistance of rice, and they could be used to identify the drought resistance of rice in Ningxia. In addition, the drought resistance of rice was graded qualitatively according to the subordinate function value of corresponding drought resistance coefficient. The results showed that among the 49 rice cultivars from Ningxia,6 rice cultivars were highly drought resistant, and 9 rice cultivars were moderately drought resistant, suggesting that the evaluation method was feasible and effective.

Predictability of Vesicoureteral Reflux Using Interlobar Renal Arterial Resistive Indices in Sonographically Normal Pediatric Kidneys-Preliminary Results

Objective: To prospectively evaluate the diagnostic utility of interlobar renal arterial resistive index values, in predicting the presence of vesicoureteral reflux in children with sonographically normal appearing kidneys. Methods: We investigated 35 children with a history of urinary tract infection with grayscale and color Doppler ultrasound (US) fol-lowed by a standard voiding cystouretherogram to assess the presence of vesicoureteral reflux. All renal units (individ-ual kidneys) were morphologically normal without evidence of hydronephrosis. Resistive index (RI) was measured at the level of the interlobar arteries. Results: Of a total of 67 kidney units, 3 kidney units yielded no diagnostic results due to technical factors (crying, agitation). 46 kidney units (69%) were not associated with any degree of reflux. 17 kidney units (25%) were associated with low-mid grade reflux (grades I - III). 4 kidney units (6%) were associated with high grade reflux (grades IV - V). No statistically significant correlation was found between the interlobar resistive indices of sonographically normal appearing kidneys and the presence, absence, or degree of vesicoureteral reflux. Conclusions: The results of this study suggest that resistive index measurements taken in the interlobar arteries of sonographically normal appearing kidneys cannot be used to predict the presence or absence of vesicoureteral reflux.

Resistive Index for the Evaluation of Renal Damage in Diabetes Mellitus Type 2

Background: One of the most common causes of renal impairment and development of chronic kidney disease is diabetes mellitus type 2 (DM 2). The aim of this prospective study was to determine the role of Resistive Index (RI) as a non-invasive marker for the evaluation of renal impairment in patients with DM 2. Material and Methods: 47 patients with DM 2 in mean age 62.66 ± 10.081 years were included in the study for the period of one year. All of them were with well-compensated diabetes mellitus (HbA1c Results: Patients with RI 0.05 for all). There was significant difference between the groups according to serum creatinine (p = 0.026), GFR (p = 0.044) and the degree of proteinuria (p = 0.001). There was a positive correlation between RI and serum creatinine (r = 0.418;p = 0.001) and between RI and proteinuria (r = 0.396;p = 0.004). A negative correlation relationship between RI and GFR values was found (r = –0.413;p = 0.011). Conclusions: RI may be used as an indicator for the assessment of the severity of renal impairment in patients with DM 2. It correlates well with serum creatinine, GFR and proteinuria, which are proven biochemical parameters indicating the degree of renal damage in patients with DM 2.