Gastric adenocarcinoma of the fundic gland type shares common genetic and phenotypic features with pyloric gland adenoma

Gastric adenocarcinoma of the fundic gland type (GAFG) and pyloric gland adenoma (PGA) have recently been recognized as rare types of neoplasia. We performed comparative immunohistochemical and genetic analyses of 3 GAFGs and 12 PGAs. All of the 3 GAFGs were diffusely positive for pepsinogen‐I, MIST1 and MUC6, indicating the predominantly chief cell/mucous neck cell differentiation of these tumors. A small number of H.K‐ATPase‐positive parietal cells were also scattered. PGAs invariably exhibited diffuse MUC6 and TFF2 expression, consistent with the pyloric gland differentiation of these tumors. Ten of the 12 PGAs also unexpectedly exhibited focal expression of pepsinogen‐I and MIST1, suggesting that PGAs often show focal chief cell differentiation and phenotypically resemble mucous neck cells rather than pyloric glands. The mutation analyses revealed activating GNAS mutations, which have been reported to be frequently detected in PGAs, in two of the GAFGs. While GAFGs and PGAs are morphologically distinct lesions, our observations showed their partially overlapping immunohistochemical profiles and shared presence of GNAS mutations, in addition to their common occurrence in the fundic gland mucosa. Based on these observations, we suggest that both GAFGs and PGAs are closely related lesions characterized by a mucous neck cell/chief cell lineage phenotype.     

Influences of the depth-dependent material inhomogeneity of articular cartilage on the fluid pressurization in the human knee

The material properties of articular cartilage are depth-dependent, i.e. they differ in the superficial, middle and deep zones. The role of this depth-dependent material inhomogeneity in the poromechanical response of the knee joint has not been investigated with patient-specific joint modeling. In the present study, the depth-dependent and site-specific material properties were incorporated in an anatomically accurate knee model that consisted of the distal femur, femoral cartilage, menisci, tibial cartilage and proximal tibia. The collagen fibers, proteoglycan matrix and fluid in articular cartilage and menisci were considered as distinct constituents. The fluid pressurization in the knee was determined with finite element analysis. The results demonstrated the influences of the depth-dependent inhomogeneity on the fluid pressurization, compressive stress, first principal stress and strain along the tissue depth. The depth-dependent inhomogeneity enhanced the fluid support to loading in the superficial zone by raising the fluid pressure and lowering the compressive effective stress at the same time. The depth-dependence also reduced the tensile stress and strain at the cartilage–bone interface. The present 3D modeling revealed a complex fluid pressurization and 3D stresses that depended on the mechanical contact and relaxation time, which could not be predicted by existing 2D models from the literature. The greatest fluid pressure was observed in the medial condyle, regardless of the depth-dependent inhomogeneity. The results indicated the roles of the tissue inhomogeneity in reducing deep tissue fractures, protecting the superficial tissue from excessive compressive stress and improving the lubrication in the joint.     

Methodology to determine skull bone and brain responses from ballistic helmet-to-head contact loading using experiments and finite element analysis

The objective of the study was to obtain helmet-to-head contact forces from experiments, use a human head finite element model to determine regional responses, and compare outputs to skull fracture and brain injury thresholds. Tests were conducted using two types of helmets (A and B) fitted to a head-form. Seven load cells were used on the head-form back face to measure helmet-to-head contact forces. Projectiles were fired in frontal, left, right, and rear directions. Three tests were conducted with each helmet in each direction. Individual and summated force- and impulse-histories were obtained. Force-histories were inputted to the human head–helmet finite element model. Pulse durations were approximately 4 ms. One-third force and impulse were from the central load cell. 0.2% strain and 40 MPa stress limits were not exceeded for helmet-A. For helmet-B, strains exceeded in left, right, and rear; pressures exceeded in bilateral directions; volume of elements exceeding 0.2% strains correlated with the central load cell forces. For helmet-A, volumes exceeding brain pressure threshold were: 5–93%. All elements crossed the pressure limit for helmet-B. For both helmets, no brain elements exceeded peak principal strain limit. These findings advance our understanding of skull and brain biomechanics from helmet–head contact forces.     

A pulsatile blood vessel system for a femoral arterial access clinical simulation model

The model-based, rapid-prototyping-enabled design and manufacture of a pulsatile blood vessel (PBV) for high-fidelity mannequin-based clinical simulations is presented. The PBV presented here is a pressurized, flexible tube with alternating fluid pressure created by a pump to mimic the behavior of a human vessel in response to pulsatile pressure. The use of PBVs is important for the fidelity of a clinical simulator that requires residents to palpate and/or access the vessel. In this study, a PBV is presented which features the integration of 3D modeling using patient-specific computed tomography (CT) data, mold fabrication using rapid-prototyping, and finite element method for estimating the required pumping pressure to generate the same level of force (about 1.5 N) experienced by the user through palpation. The relationship between this palpation force and the vessel pressure is studied using two strategies: finite element analysis (FEA) and experiments in a femoral arterial access simulator with a pump, artificial vessel, and surrounding phantom tissue. The experimental results show a discrepancy of 8.7% from the FEA-predicted value. Qualitative validation is done by exposing and surveying 19 interventional cardiology residents at four major educational institutions to the simulator for accuracy of its feel. The overall survey results are positive.     

Validation of multiple subject-specific finite element models of unicompartmental knee replacement

Accurate computer modelling of the fixation of unicompartmental knee replacements (UKRs) is a valuable design tool. However, models must be validated with in vitro mechanical tests to have confidence in the results. Ten fresh-frozen cadaveric knees with differing bone densities were CT-scanned to obtain geometry and bone density data, then implanted with cementless medial Oxford UKRs by an orthopaedic surgeon. Five strain gauge rosettes were attached to the tibia and femur of each knee and the bone constructs were mechanically tested. They were re-tested following implanting the cemented versions of the implants.Finite element models of four UKR tibiae and femora were developed. Sensitivity assessments and convergence studies were conducted to optimise modelling parameters. The cemented UKR pooled R² values for predicted versus measured bone strains were 0.85 and 0.92 for the tibia and femur respectively. The cementless UKR pooled R² values were slightly lower at 0.62 and 0.73 which may have been due to the irregularity of bone resections. The correlation of the results was attributed partly to the improved material property prediction method used in this project. This study is the first to validate multiple UKR tibiae and femora for bone strain across a range of specimen bone densities.     

以量化评估策略为核心的调节式护理干预对胃癌病人术后胃肠功能恢复及并发症预防的影响

目的:探讨以量化评估策略为核心的调节式护理干预对胃癌病人术后胃肠功能恢复及并发症预防的影响。方法:选取2016年7月—2018年7月收治的140例胃癌病人作为研究对象,将其以随机抽签法分为观察组及对照组。对照组给予常规护理干预,观察组给予以量化评估策略为核心的调节式护理干预。比较两组病人术后胃肠功能恢复情况、并发症发生情况,采用一般自我效能感量表(GSES)和生存质量测量量表简表评估两组病人干预前后自我效能感以及生活质量变化情况。结果:观察组病人胃肠功能恢复时间均短于对照组(均P<0.05)。观察组病人术后并发症发生率低于对照组(P<0.05)。两组病人干预后GSES评分高于干预前,且观察组高于对照组(均P<0.05)。观察组病人干预后生活质量评分高于对照组(均P<0.05)。结论:以量化评估策略为核心的调节式护理干预可有效促进胃癌病人术后胃肠道功能恢复,有利于降低术后并发症发生风险,提高病人的自我效能感以及生活质量。     

61例晚期胃癌病人疾病不确定感及应对方式探讨

目的:探讨晚期胃癌病人疾病不确定感及应对方式。方法:选取2016年1月—2018年12月医院收治的61例晚期胃癌病人,以中文版Mishel疾病不确定感量表(MUIS)、医学应对问卷(MCMQ)对病人疾病不确定感及应对方式进行评价,比较治疗前后MUIS、MCMQ各维度得分情况,并分析疾病不确定感与应对方式的关系。结果:61例晚期胃癌病人MUIS得分中不明确性维度得分最高,其次是复杂性、不可预测性、信息缺乏性维度得分;治疗后不明确性、复杂性、不可预测性、信息缺乏性维度得分均低于治疗前,差异具有统计学意义(P<0.05)。61例晚期胃癌病人治疗前MCMQ得分中“回避”维度得分最高,其次是“面对”“屈服”维度;治疗后“面对”维度得分最高,其次是“回避”“屈服”维度。治疗后“屈服”“回避”维度得分低于治疗前,“面对”维度得分高于治疗前,差异具有统计学意义(P<0.05)。“屈服”“回避”维度得分均与不明确性、复杂性、不可预测性、信息缺乏性维度得分呈正相关,“面对”维度得分与不明确性、复杂性、不可预测性、信息缺乏性维度得分呈负相关(P<0.05)。结论:晚期胃癌病人明确存在较高水平的疾病不确定感,其中“不明确性”维度得分最高,且治疗前主要应对方式为“回避”。疾病不确定感与应对方式可相互影响,屈服、回避可导致较高的疾病不确定感,而面对疾病是晚期胃癌病人积极的应对方式。     

胃癌病人自杀干预研究进展

对胃癌病人自杀的高危因素及其干预措施的研究进展进行综述,以期引起医护人员对胃癌病人心理健康的关注,尤其是对有自杀倾向的病人,采取针对性的干预防范措施以减少自杀等不良事件的发生。建议护理科研人员能尽早制定适用于胃癌等恶性肿瘤病人的自杀评估量表;同时建议护理科研人员对胃癌病人的自杀情况进行更深入的研究,从而为自杀干预提供更多参考资料。     

乳腺磁共振背景实质强化的研究进展

乳腺癌作为女性最常见的恶性肿瘤,其发病率及死亡率都较高,且不同分子亚型乳腺癌生物学表现及临床治疗、预后各不相同,寻找乳腺癌针对性和个性化诊断及治疗的影像学标记物是目前研究的热点。乳腺背景实质强化(background parenchymal enhancement,BPE)是正常纤维腺体组织的生理性强化,受多种因素的影响,并在乳腺疾病的诊断及治疗预后方面有着重要的诊断价值,BPE水平升高与乳腺癌发病风险相关,并可能评估乳腺癌新辅助化疗的疗效。作者就BPE的影响因素及在乳腺癌筛查、诊断及治疗评估中的作用加以综述。     

乳腺癌DCE-MRI参数及ADC与病理分子预后标记物的相关性分析

目的分析乳腺癌动态对比增强磁共振成像(dynamic contrast-enhanced magnetic resonance imaging,DCE-MRI)参数、表观扩散系数(apparent diffusion coefficient,ADC)与病理分子预后标记物的相关性。材料与方法回顾性分析我院106例乳腺癌患者临床资料,分别比较雌激素受体(estrogen receptor,ER)、孕激素受体(progesterone receptor,PR)、细胞增殖抗原Ki67及雄激素受体(androgen receptor,AR)阳性表达与阴性表达者DCE-MRI参数、ADC差异,并分析DCE-MRI参数、ADC与ER、PR、Ki67、AR表达的相关性。结果经Spearman秩相关检验,发现ER、PR及AR阳性表达与直径、边缘毛刺呈显著负相关(P<0.05),AR表达阳性表达还与达峰时间(time to peak,TTP)、ADC值呈显著正相关(P<0.05);Ki67阳性表达与直径、边缘毛刺呈显著正相关(P<0.05),与TTP、ADC值呈显著负相关(P<0.05)。结论DCE-MRI形态学参数及TTP、ADC值与乳腺癌分子生物学标记物具有一定相关性,对判断乳腺癌预后有利。