术前口服依他昔布对妇科手术后病人自控镇痛的影响

目的:观察妇科开腹手术患者术前给予依他昔布120mg对术后自控镇痛(PCA)吗啡用量的影响及其副作用。方法:随机选取全麻下接受妇科开腹全子宫(双附件)切除患者40例,术前分别给予安慰剂或依他昔布120mg口服。在手术后观察24h患者PCA吗啡用量,同时记录患者的疼痛评分和满意度评分,并观察不良反应。结果:术后PCA吗啡24h消耗量在依他昔布组为9.4±7.6mg,显著低于安慰剂组15.7±8.9mg。两组患者24h内对PCA的按压次数依他昔布组也低于安慰剂组(P<0.05)。其中术后3、6、8和12hPCA吗啡消耗量在两组间无显著差异。两组患者术后24h疼痛评分和对镇痛治疗的满意度也无差异。两组患者不良反应的发生率亦无差别。结论:在妇科开腹手术患者术前应用依他昔布120mg可使患者术后PCA吗啡消耗量降低,且在术后12h后下降明显。未发现与依他昔布应用相关的副作用。     

Influence of respiration and portal pressure on transabdominal duplex Doppler ultrasound measurement of portal blood flow: a porcine model for experimental studies

Transabdominal duplex Doppler ultrasonography (TDDU) is commonly used for measuring hepatic blood flow (HBF) in clinical practice. Flow velocity and the cross-sectional area (CSA) of vessels are obtained separately and used to compute blood flow. Respiration and changes in portal pressure are known to cause variations in the CSA of the portal vein, but the impact of these parameters on TDDU measurement of portal blood flow is unclear. Eight Yorkshire pigs (20.7-25.1 kg) were used for the study. TDDU determination of portal blood flow was carried out using CSA of the portal vein obtained at inspiration (maximal) and at expiration (minimal) for computation, and the differences obtained were compared. Determination of HBF was carried out simultaneously on the same animals using diisopropyliminodiacetic acid (DISIDA) clearance. A physiological increase in portal pressure was then created by 50% hepatectomy and TDDU measurement similarly carried out on the second postoperative day. Computing portal blood flow in the intact liver using maximal and minimal CSA gave rise to a mean difference of 7.0 ml kg(-1) min(-1) (P < 0.001). A significant correlation was obtained between HBF and portal flow computed from maximal CSA (Pearson's correlation = 0.85, P < 0.033). The respiratory index of the portal vein (maximal CSA/minimal CSA) decreased from 1.5 to 1.2 after hepatectomy, which also caused a 90% increase in portal pressure. Respiration and portal pressure thus significantly impact on TDDU determination of HBF, and in this porcine model, computation using maximal CS more accurately reflects HBF.     

Trastuzumab-mediated antibody-dependent cellular cytotoxicity against esophageal squamous cell carcinoma.

PURPOSE: In the present study, we investigated the degree of protein expression and gene amplification of HER-2 in esophageal squamous cell carcinoma (SCC) cell lines and freshly isolated tumors, and trastuzumab-mediated biological activity, in particular antibody-dependent cellular cytotoxicity (ADCC) against HER-2-expressing esophageal SCC cell lines. EXPERIMENTAL DESIGN: Ten different SCC cell lines with various levels of HER-2 status evaluated by flow cytometry, immunocytochemistry (HercepTest), and fluorescence in situ hybridization were evaluated for ADCC, growth inhibitory, or apoptosis-inducing activities mediated by trastuzumab. RESULTS: Trastuzumab induced ADCC against HER-2-expressing esophageal SCC and the activities reflected the degree of HER-2 expression analyzed by flow cytometric analysis, but not by HercepTest nor fluorescence in situ hybridization analysis. Furthermore, trastuzumab-mediated ADCC against transforming growth factor-beta-producing SCC was enhanced by the treatment with SB-431542, which is a selective inhibitor of the phosphorylation induced by transforming growth factor-beta. There were very marginal effects of anti-proliferative or apoptosis-inducing activities mediated by trastuzumab for HER-2-expressing esophageal SCC. CONCLUSION: HER-2-expressing esophageal SCC cells could be killed by trastuzumab-mediated ADCC and the activity reflected the degree of HER-2 expression detected by flow cytometry.     

Shear Wave Elastography: A Review on the Confounding Factors and Their Potential Mitigation in Detecting Chronic Kidney Disease

Early detection of chronic kidney disease is important to prevent progression of irreversible kidney damage, reducing the need for renal transplantation. Shear wave elastography is ideal as a quantitative imaging modality to detect chronic kidney disease because of its non-invasive nature, low cost and portability, making it highly accessible. However, the complexity of the kidney architecture and its tissue properties give rise to various confounding factors that affect the reliability of shear wave elastography in detecting chronic kidney disease, thus limiting its application to clinical trials. The objective of this review is to highlight the confounding factors presented by the complex properties of the kidney, in addition to outlining potential mitigation strategies, along with the prospect of increasing the versatility and reliability of shear wave elastography in detecting chronic kidney disease.     

Vapor condensation with daytime radiative cooling

A radiative vapor condenser sheds heat in the form of infrared radiation and cools itself to below the ambient air temperature to produce liquid water from vapor. This effect has been known for centuries, and is exploited by some insects to survive in dry deserts. Humans have also been using radiative condensation for dew collection. However, all existing radiative vapor condensers must operate during the nighttime. Here, we develop daytime radiative condensers that continue to operate 24 h a day. These daytime radiative condensers can produce water from vapor under direct sunlight, without active consumption of energy. Combined with traditional passive cooling via convection and conduction, radiative cooling can substantially increase the performance of passive vapor condensation, which can be used for passive water extraction and purification technologies.

Energy and clean water are global challenges that are intertwined in an unfavorable way: even in areas where water is abundant, energy may not be available to purify it for human use (1, 2). There has been strong interest in developing passive technologies to purify or harvest water without using fuel or electricity. In this context, passive vapor condensation becomes particularly important because many passive water technologies go through the vapor phase of water in their harvesting or purification processes.Traditional vapor condensation technique is based on convective and conductive heat exchange with ambient environments. This technique is widely used in systems with hot vapors (3–6). However, with ever-increasing emphasis on passive systems, there are many situations in which warm- or even room-temperature vapor needs to be effectively condensed, such as extracting water from atmosphere (7–9) and warm vapor generated from high-efficiency solar evaporation (10). For vapor at such temperatures, most traditional condensers fail. For this reason, there is a clear need for a condensation technique to complement traditional condensers.A different technique is based on radiative vapor condensation. Darkling beetles in the Namib desert (11) use this technique to collect water. Their bodies function as a cooling surface by shedding thermal energy through midinfrared (mid-IR) radiation toward a clear nighttime sky, generating dew from humid air. This mechanism is also used by commercial radiative dew condensers (7–9). However, neither Namib beetle nor existing dew condensers can operate in the daytime (7). Those nighttime radiative condensers are incompatible with many emerging water technologies that require 24 h operation or direct access to sunlight.Recently, Fan et al. showed that passive radiative cooling to subambient temperatures can be realized even during the daytime, by integrating a high-efficiency solar reflector with a high-emissivity thermal emitter in the mid-IR atmospheric transparency window (12). Using this work as a basis, here we demonstrate a daytime radiative condenser. Compared to existing radiative vapor condensers (7–9), our condenser can function even in the presence of sunlight, which is essential for integration into passive water-harvesting systems that mainly operate during daytime.     

Computed tomographic evaluation of the role of craniofacial and upper airway morphology in obstructive sleep apnea in Chinese

OBJECTIVES: To evaluate the relationship between cephalometric parameters, upper airway morphological factors and obstructive sleep apnea (OSA) in Chinese subjects. DESIGN: Polysomnogram (PSG) were performed and scored using standard criteria. Supine lateral cephalometric parameters and pharyngeal cross-sectional areas at the level of velopharynx (VA) and hypopharynx (HA) were measured from computed tomographic scans. The roles of these parameters and other anthropometric/demographic characteristics in OSA (apnea hypopnea index, AHI > or = 5) and their relationship with severity of OSA were explored by multiple logistic and multinominal regression analysis. RESULTS: Ninety-two subjects, ranging from normal (n = 36), mild/moderate OSA (n = 34) to severe OSA (n = 22), were evaluated. Compared with normal subjects, OSA subjects were heavier (body mass index 27 vs. 24 kg/m2) and older (47 vs. 42 years of age); had smaller VA size and VA to HA ratio, lower positioned hyoid bone, longer and thicker soft palate, and more retropositioned mandible relative to maxilla. After controlling for body mass index and age, subjects with severe OSA (AHI > 30) had more retropositioned mandible relative to maxilla (odds ratio, OR 1.31, P = 0.044) and longer soft palate (OR 1.16, P = 0.01), while those with mild/moderate OSA had larger VA to HA ratio (OR 0.17, P = 0.018). CONCLUSIONS: Craniofacial factors and upper airway morphology contributed to severity of OSA in Chinese subjects. Having controlled for obesity, more retropositioned mandible was associated with more severe OSA.