Extracorporeal CO(2) removal in ARDS

Acute respiratory distress syndrome remains one of the most clinically vexing problems in critical care. As technology continues to evolve, it is likely that extracorporeal CO(2) removal devices will become smaller, more efficient, and safer. As the risk of extracorporeal support decreases, devices' role in acute respiratory distress syndrome patients remains to be defined. This article discusses the functional properties and management techniques of CO(2) removal and intracorporeal membrane oxygenation and provides a glimpse into the future of long-term gas-exchange devices.     

单体素氢质子磁共振波谱在脊柱转移瘤中的初步应用研究

目的探讨单体素波谱探讨氢质子波谱在椎体转移瘤中的应用价值。方法 15例脊柱转移瘤患者采用单体素频谱(SV)空间定位和点分辨频谱(PRESS)序列对选定的病变椎体及临近正常椎体进行波谱采集。定量分析感兴趣椎体的脂与水的比率(LWR)及脂肪百分含量(FF%)。结果脊柱转移瘤组椎体显示脂峰明显降低。转移瘤组椎体的平均LWR为0.03±0.03,FF%为(3.57±2.11)%,邻近正常椎体的平均LWR为0.68±0.25,FF%为(37.82±9.12)%。结论单体素1 H-MRS可以量化地分析脊柱转移瘤椎体的水和脂肪的变化。     

Hemodynamic effects of partial liquid ventilation with perfluorocarbon in acute lung injury

Objective To assess the effect of partial liquid ventilation with perfluorocarbons on hemodynamics and gas exchange in large pigs with induced acute lung injury (ALI).Design Randomized, prospective, double-control, experimental study.Setting Experimental intensive care unit of a university.Materials Eighteen large pigs (50±5 kg body weight) with an average anterior posterior thoracic diameter of 24 cm and induced acute lung injury.Interventions All animals were surfactant depleted by lung lavage to aP _aO₂ below 100 mmHg and randomized to receive either perflubron (n=6) or saline (n=6) in five intratracheal doses of 5 ml/kg at 20-min intervals, or no instillation (n=6).Measurements and results In all animals heart rate, arterial pressures, pulmonary pressures, cardiac output and blood gases were recorded at 20-min intervals. There was no deleterious effect on any hemodynamic parameter in the perflubron group, whereas systolic and mean pulmonary arterial pressure values showed a persistent decrease after the first 5 ml/kg of perflubron, from 48.7±14.1 to 40.8±11.7 mmHg and from 39.7±13.2 to 35.2±12.0 mmHg, respectively. Perflubron resulted in a significant (ANOVAP<0.01), dose-dependent increase inP _aO₂ values from 86.3±22.4 to a maximum of 342.4±59.4 mmHg at a dose of 25 ml/kg; the other groups showed no significant increase inP _aO₂.Conclusions Tracheal instillation of perflubron in induced ALI results in a dose-dependent increase inP _aO₂ and has no deleterious effect on hemodynamic parameters.     

利用1H MRS进行在体乳腺癌中复合胆碱外参照法定量的研究

目的 探讨如何用外参照法利用氢质子磁共振波谱(¹H MRS)对在体乳腺癌中的复合胆碱进行绝对定量。方法 配制5个不同浓度的胆碱测试模型及一个胆碱校对模型。在基本相同的条件下,对各测试模型的同一位置进行MRS采集,统计胆碱峰峰下面积与胆碱浓度之间是否呈线性相关。对水模进行T1WI成像,绘制不同位置信号强度的变化曲线。对同一校对模型的同一位置采用不同大小的体素进行MRS采集,统计体素大小与胆碱峰峰下面积是否呈线性相关。测量胆碱测试模型及校对模型中胆碱的T1及T2值。验证胆碱浓度绝对定量的校对公式。对7例乳腺癌病人进行乳腺MRS采集,利用校对公式以胆碱校对模型中的胆碱浓度为参照计算出乳腺癌中复合胆碱的浓度。结果 胆碱测试模型的胆碱峰峰下面积与胆碱浓度之间呈线性相关。同一模型同一位置胆碱峰峰下面积与体素大小呈线性相关。测试模型及校对模型中胆碱的T1及T2值分别为1902.5/1032.8、2426.3/989.4。利用校对公式估计出的校对模型的胆碱浓度为(5.2±1.0)mM,与校对模型的实际浓度比较二者无显著差异(t＝0.6,P>0.05)。7例乳腺癌中的复合胆碱浓度为(3.64±2.52)mM。结论 外参照法是进行乳腺癌中复合胆碱浓度定量的可行及可靠的方法。     

尾吊大鼠血液细胞电阻抗谱的Cole-Cole模型分析

目的利用Cole-Cole数学模型研究尾吊大鼠血液细胞电阻抗频谱的变化。方法通过非线性数值计算,对血液细胞的Bode图,Nyquist图和Nichols图进行Cole-Cole方程的曲线拟合,比较对照组(Con)与尾吊组(SUS)Cole-Cole模型参数。结果尾吊60 d大鼠血液细胞电阻抗频谱Cole-Cole模型参数变化显示:阻抗高频极限值(R∞)和阻抗增量(ΔR1,ΔR2)减小;特征频率(fC1,fC2)和β驰豫散射角(α1,α2)增加。结论可以通过Cole-Cole数学方程参数表达尾吊大鼠血液细胞电阻抗频谱特性变化。     

DWI和~1H-MRS在肝纤维化中的诊断价值

目的:探讨扩散加权成像(DWI)与氢质子波谱分析(1 H-MRS)在肝纤维化中的诊断价值。方法:使用腹腔注射CCl4溶液法诱导建立兔肝纤维化模型并进行DWI和1 H-MRS检查。DWI使用SE-EPI序列(b1=0s/mm2,b2=600s/mm2),1 H-MRS使用单体素点分辨波谱分析(PRESS)序列(TR 1500ms,TE 35ms),测量表观扩散系数(ADC)值及胆碱(Cho)和脂质(lipid)波峰下面积的比值(Cho/lipid)。以病理学肝纤维化分期为基础,将兔划分为无肝纤维化组(S0)、轻度-中度纤维化组(S1-S2)和重度纤维化及肝硬化组(S3-S4),比较不同组间ADC值和Cho/lipid变化规律。结果:随肝纤维化程度加重,ADC值依次降低(P<0.01),Cho/lipid依次升高(P<0.05);重度纤维化及肝硬化组与另两组ADC值及Cho/lipid差异均具有统计学意义(P均<0.05)。结论:DWI和1 H-MRS具备一定的定量肝纤维化及检测重度纤维化及肝硬化的能力。     

Role of artificial intelligence and vibrational spectroscopy in cancer diagnostics

ABSTRACT

Introduction

Raman and Infrared spectroscopic techniques are being used for the analysis of different types of cancers and other biological molecules. It is possible to identify cancers from normal tissues both in fresh and fixed tissues. These techniques can be used not only for the early diagnosis of cancer but also for monitoring the progression of the disease. Furthermore, chemical pathways to the progression of the disease process can be understood and followed.     

New Technologies in Breast Cancer Surgery

Since breast-conserving surgery has become the gold standard for early breast cancer, the development of less radical or less burdensome technologies has been pressed for in order to preserve the patient from unnecessary harm through the operative procedure. Different technical approaches are under evaluation, and some of them are already being used in the clinical setting. The aim of this article is to present a perspective on future breast cancer surgery by shedding light on the current innovative and new techniques.     

Changes in tissue oxygenation following caudal epidural blockade in infants and children

Background: Adequate tissue oxygenation is required for effective white blood cell function and bactericidal activity. Decreased tissue oxygenation has been shown to be a risk factor for perioperative wound infections. Regional anesthetic techniques result in a functional sympathetic block and may increase tissue oxygenation. The purpose of the current study is to prospectively evaluate changes in tissue oxygenation using a non‐invasive near‐infrared spectroscopy (NIRS) device following caudal epidural block in infants and children. Methods: Following standard anesthetic induction and general anesthesia with an endotracheal tube or laryngeal mask airway, the NIRS sensors were placed on two sites. One sensor was placed at a site affected by the caudal block (lower extremity), and the other sensor was placed on the arm, a site unaffected by the caudal block (upper extremity). The NIRS value was recorded at baseline and then again at 15, 30, and 45 min after the block. The caudal block was performed, after anesthetic induction and NIRS sensor placement, using bupivacaine 0.25% with epinephrine 1 : 200 000 or ropivacaine 0.2% with epinephrine 1 : 200 000 at a dose of 1 ml·kg^?1. The inspired oxygen concentration after induction was held constant at 30%, and anesthesia was maintained with sevoflurane at 1 MAC. No other pharmacologic agents were administered. Results: Following the caudal epidural block, there was a statistically significant increase in the tissue oxygenation from the affected site. The NIRS value increased from a baseline of 83 ± 4 to 87 ± 3 at 15 min (P = 0.0001 vs baseline), 88 ± 4 at 30 min (P < 0.0001 vs baseline), and 87 ± 4 at 45 min (P < 0.0001 vs baseline). No change was noted on the unaffected site (upper extremity). Conclusion: There was a statistically significant increase in tissue oxygenation as measured by NIRS following caudal anesthesia in infants and children. Although the magnitude of the change was less, this study confirms the results of previous studies in adults showing an increase in tissue oxygenation following regional blockade.     

Altered plasma membrane dynamics of bone morphogenetic protein receptor type Ia in a low bone mass mouse model

Bone morphogenetic proteins (BMPs) are growth factors that initiate differentiation of bone marrow stromal cells to osteoblasts and adipocytes, yet the mechanism that decides which lineage the cell will follow is unknown. BMP2 is linked to the development of osteoporosis and variants of BMP2 gene have been reported to increase the development of osteoporosis. Intracellular signaling is transduced by BMP receptors (BMPRs) of type I and type II that are serine/threonine kinase receptors. The BMP type I a receptor (BMPRIa) is linked to osteogenesis and bone mineral density (BMD). BMPRs are localized to caveolae enriched with Caveolin1 alpha/beta and Caveolin beta isoforms to facilitate signaling. BMP2 binding to caveolae was recently found to be crucial for the initiation of the Smad signaling pathway. Here we determined the role of BMP receptor localization within caveolae isoforms and aggregation of caveolae as well as BMPRIa in bone marrow stromal cells (BMSCs) on bone mineral density using the B6.C3H-6T as a model system. The B6.C3H-6T is a congenic mouse with decreased bone mineral density (BMD) with increased marrow adipocytes and decreased osteoprogenitor proliferation. C57BL/6J mice served as controls since only a segment of Chr6 from the C3H/HeJ mouse was backcrossed to a C57BL/6J background. Family of image correlation spectroscopy was used to analyze receptor cluster density and co-localization of BMPRIa and caveolae. It was previously shown that BMP2 stimulation results in an aggregation of caveolae and BMPRIa. Additionally, BMSCs isolated from the B6.C3H-6T mice showed a dispersion of caveolae domains compared to C57BL/6J. The aggregation of BMPRIa that is necessary for signaling to occur was inhibited in BMSCs isolated from B6.C3H-6T. Additionally, we analyzed the co-localization of BMPRIa with caveolin-1 isoforms. There was increased percentage of BMPRIa co-localization with caveolae compared to C57BL/6J. BMP2 stimulation had no effect on the colocalization of BMPRIa with caveolin-1. Disrupting caveolae initiated Smad signaling in the isolated BMSCs from B6.C3H-6T. These data suggest that in congenic 6T mice BMP receptors aggregation is inhibited causing an inhibition of signaling and reduced bone mass.