糖尿病患者掌、指骨X线测量及其临床意义

６３例糖尿病患者、４０例正常人行左手Ｘ片检查并测量第２掌骨及中指第２指骨骨长（Ｌ）中点的横径（Ｄ）、髓腔宽度（ｄ），以此计算掌、指骨参数，包括Ｄ一ｄ／Ｄ、Ｄ２一ｄ２、Ｄ２一ｄ２／Ｄ２、Ｄ２一ｄ２／ＤＬ。以掌、指骨指数（Ｄ一ｄ／Ｄ）分别低于４３％及３７％为骨质疏松，则糖尿病性骨质疏松症的发病率为４７．６２％。病程长、病情重、失治者易伴发，且多有尿钙、尿磷排泄增加。认为掌、指骨Ｘ线测量可作为判断糖尿病患者有无骨质疏松的一种方法。     

Quantitative Monitoring of Extracellular Matrix Production in Bone Implants by <Superscript>13</Superscript>C and <Superscript>31</Superscript>P Solid-State Nuclear Magnetic Resonance Spectroscopy

We used ³¹P and ¹³C solid-state nuclear magnetic resonance (NMR) spectroscopy to detect and analyze the major organic and inorganic components (collagen type I and bioapatite) in natural rabbit bone and β-tricalcium phosphate implants loaded with osteogenically differentiated mesenchymal stem cells. High-resolution solid-state NMR spectra were obtained using the magic-angle spinning (MAS) technique. The ³¹P NMR spectra of bone specimens showed a single line characteristic of bone calcium phosphate. ¹³C cross-polarization (CP) MAS NMR spectra of bone exhibited the characteristic signatures of collagen type I with good resolution for all major amino acids in collagen. Quantitative measurements of ¹³C-¹H dipolar couplings indicated that the collagen segments are very rigid, undergoing only small amplitude fluctuations with correlation times in the nanosecond range. In contrast, directly polarized ¹³C MAS NMR spectra of rabbit bone were dominated by signals of highly mobile triglycerides. These quantitative investigations of natural bone may provide the basis for a quality control of various osteoinductive bone substitutes. We studied the formation of extracellular bone matrix in artificial mesenchymal stem cell-loaded β-tricalcium phosphate matrices that were implanted into the femoral condyle of rabbits. The NMR spectra of these bone grafts were acquired 3 months after implantation. In the ³¹P NMR spectra, β-tricalcium phosphate and bone calcium phosphate could be distinguished quantitatively, allowing recording of the formation of the natural bone matrix. Further, ¹³C CPMAS allowed detection of collagen type I that had been produced in the implants. Comparison with the spectroscopic data from natural bone allowed assessment of the quality of the bone substitute material. J. S. and M. P. contributed equally to this study     

1024例儿童尿流率调查

目的 寻求长沙地区儿童尿流率正常值及其列线图。方法 对1024名正常儿童进行1048次尿流率检测。将所得资料按性别、年龄、体表面积、排尿量分组后进行统计学分析，并绘制出各组相应的列线图以阐明尿量、体表面积、平均尿流率、最大尿流率4者的相互关系。结果 正常儿童尿流率曲线为典型的钟形曲线。〈7岁男性儿童的最大尿流率随年龄增加而增加，年龄每增加1岁最大尿流率增加1．7ml／s，〉7岁者其最大尿流率同成年人相仿。〈9岁女性儿童的最大尿流率随年龄增加而增加，年龄每增加1岁最大尿流率增加1．2ml／s，〉9岁其最大尿流率同成年人相近。儿童最大尿流率、平均尿流率及排尿量均随体表面积增加而增加，同时，最大尿流率、平均尿流率也均随排尿量的增加而增加。结论 〈9岁的女童和〈7岁的男童最大尿流率的正常值有明显的年龄依从性。     

Optimal spatial field control for controlled release

Most distributed parameter control problems involve manipulation within the spatial domain. Such problems arise in a variety of applications including epidemiology, tissue engineering, and cancer treatment. This paper proposes an approach to solve a state‐constrained spatial field control problem that is motivated by a biomedical application. In particular, the considered manipulation over a spatial field is described by partial differential equations (PDEs) with spatial frequency constraints. The proposed optimization algorithm for tracking a reference spatial field combines three‐dimensional Fourier series, which are truncated to satisfy the spatial frequency constraints, with exploitation of structural characteristics of the PDEs. The computational efficiency and performance of the optimization algorithm are demonstrated in a numerical example. In the example, the spatial tracking error is shown to be almost entirely due to the limitation on the spatial frequency of the manipulated field. The numerical results suggest that the proposed optimal control approach has promise for controlling the release of macromolecules in tissue engineering applications.     

Non-alcoholic steatohepatitis in liver transplant recipients diagnosed by serum cytokeratin 18 and transient elastography: A prospective study

BACKGROUNDNonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) seem common after liver transplantation.AIMTo investigate incidence and predictors of NAFLD and NASH by employing noninvasive testing in liver transplant recipients, namely controlled attenuation parameter (CAP) and the serum biomarker cytokeratin 18 (CK-18). We also evaluated the diagnostic accuracy of CK-18 and CAP compared to liver histology.METHODSWe prospectively recruited consecutive adult patients who received liver transplant at the McGill University Health Centre between 2015-2018. Serial measurements of CK-18 and CAP were recorded. NAFLD and NASH were diagnosed by CAP ≥ 270 dB/m, and a combination of CAP ≥ 270 dB/m with CK-18 > 130.5 U/L, respectively. Incidences and predictors of NAFLD and NASH were investigated using survival analysis and Cox proportional hazards.RESULTSOverall, 40 liver transplant recipients (mean age 57 years; 70% males) were included. During a median follow-up of 16.8 mo (interquartile range 15.6-18.0), 63.0% and 48.5% of patients developed NAFLD and NASH, respectively. On multivariable analysis, after adjusting for sex and alanine aminotransferase, body mass index was an independent predictor of development of NAFLD [adjusted hazard ratio (aHR): 1.21, 95% confidence interval (CI): 1.04-1.41; P = 0.01] and NASH (aHR: 1.26, 95%CI: 1.06-1.49; P < 0.01). Compared to liver histology, CAP had a 76% accuracy to diagnose NAFLD, while the accuracy of CAP plus CK-18 to diagnose NASH was 82%.CONCLUSIONNAFLD and NASH diagnosed non-invasively are frequent in liver transplant recipients within the first 18 mo. Close follow-up and nutritional counselling should be planned in overweight patients.     

DCE-MRI定量参数在卵巢癌分期诊断及预后评估中的应用研究

目的探究DCE-MRI定量参数在卵巢癌分期诊断及预后评估中的应用研究。方法选择卵巢癌患者61例作为观察组,并同期选择体检的健康女性50例作为对照组,比较两组的DCE-MRI定量参数(速率常数Kep、容量转移常数Ktrans及血管外细胞外间隙容积Ve)及表观扩散系数(ADC),并比较观察组的不同临床分期患者的DCE-MRI定量参数及ADC。随访3年,比较存活组及死亡组卵巢癌患者的DCE-MRI定量参数。结果观察组的Ktrans、Kep、Ve、ADC值水平均高于对照组,差异有统计学意义(P<0.05);不同临床分期卵巢癌患者的Ktrans、Kep、Ve、ADC值水平比较,差异有统计学意义(P<0.05);Ktrans、Kep、Ve水平与卵巢癌分期呈正相关(P<0.05),ADC值水平与卵巢癌分期呈负相关(P<0.05);存活组的Ktrans、Kep、Ve水平均低于死亡组(P<0.05)。结论 DCE-MRI定量参数能够有助临床判断卵巢癌分期,并了解肿瘤微血管状态,从而判断预后。     

18 F-FDG PET/CT在三阴性乳腺癌分子分型诊断中的价值

目的 探究¹⁸F-氟脱氧葡萄糖-正电子体层扫描成像(¹⁸F-FDG PET/CT)在三阴性乳腺癌分子分型诊断中的价值。方法 回顾性分析2010年1月1日至2022年12月31日在天津医科大学肿瘤医院行¹⁸F-FDG PET/CT检查的227例乳腺癌患者的临床和影像学资料,根据乳腺癌原发灶雌激素受体(ER)、孕激素受体(PR)及人表皮生长因子受体2(HER-2)表达状态将患者分为三阴性乳腺癌和非三阴性乳腺癌两组;基于PET图像和CT图像,提取影像组学特征,构建影像组学模型用于预测三阴性乳腺癌的分子分型;并比较两组患者的临床资料、CT形态学特征和PET代谢参数的差异,筛选出差异有统计学意义的指标,建立联合临床特征的综合性影像组学模型。结果 与非三阴性乳腺癌相比,三阴性乳腺癌在肿瘤直径、边缘、合并同侧腋下淋巴结转移、累犯邻近皮肤乳头及PET代谢参数等方面表现出更显著的侵袭性(t=-3.19,χ²=7.30、8.10、5.34,t=3.80、3.30、3.42,P＜ 0.05)。构建的¹⁸F-FDG PET/CT影像组学模型能够有效预测三阴性乳腺癌的分子分型,受试者工作特征(ROC)曲线分析显示,曲线下面积(AUC)为0.83(95%CI 0.78~0.88),预测准确度为75.9%,灵敏度为74.5%,特异度为77.2%。构建的综合性影像组学模型AUC为0.86(95%CI 0.81~0.90),预测准确度为77.2%,灵敏度为78.6%,特异度为75.9%。结论 ¹⁸F-FDG PET/CT在三阴性乳腺癌分子分型诊断中发挥重要价值,构建的影像组学模型和综合性影像组学模型进一步提高了PET代谢参数的预测效能,有助于临床上尽早制定准确的治疗方案,从而改善患者预后。     

肝硬化患者血小板参数的变化及其临床意义

探讨肝硬化患者出凝血系统的变化及导致出血的原因,采用K4500全自动血球计数仪对60例肝硬化患者进行血小板参数检测,发现肝硬化患者血小板计数(PLT)平均血小板体积(MPV)及血小板压积(PCT),血小板分布宽度(PDW),与对照组相比均有显著性差异(P<0.01和P<0.05),出血组与非出血组比较PLT、PCT、MPV亦有显著差异(P<0.01)。血小板四项参数对肝硬化患者血小板功能及出凝血异常的判断有一定的参考价值,可作为衡量肝硬化出血倾向的重要指标之一。