微创超声乳化手术前后角膜前后表面及不同区域范围角膜参数的变化

目的：比较白内障微创超声乳化手术前后角膜前表面屈光力(ASF)、角膜真实净屈光力(TNP)和总角膜屈光力(TCRP)分布特点及角膜前后表面曲率半径比(B/F ratio)差异。

方法：前瞻性研究。收集2020-12/2021-05就诊于潍坊眼科医院行2.2mm微切口超声乳化白内障吸除联合人工晶状体植入术的年龄相关性白内障患者156例156眼。术前及术后3mo行Pentacam眼前节生物测量仪检查，收集以角膜顶点和以瞳孔为中心2、4、6mm环上和区域内ASF、TNP和TCRP，以及手术前后B/F ratio。

结果：术后3mo，以角膜顶点为中心2mm直径环上和区域内ASF值较术前均无差异(均P>0.05)，而4、6mm直径环上和区域内ASF值较术前均有差异(均P<0.05)； 以瞳孔为中心2mm直径环上及区域内ASF值较术前均无差异(均P>0.05)。以角膜顶点为中心和以瞳孔为中心2、4、6mm直径环上和区域内TNP、TCRP值较术前均有差异(均P<0.05)。术前以角膜顶点为中心和瞳孔为中心在2mm与6mm之间环上和4mm与6mm之间环上TCRP值均有差异(均P<0.0167)； 在2mm与6mm区域内TCRP值均有差异(均P<0.0167)； 术后3mo，以角膜顶点为中心和瞳孔为中心环上TCRP值在2mm与6mm之间、4mm与6mm之间均有差异(均P<0.0167)，而以角膜顶点为中心和瞳孔为中心区域内TCRP值仅在2mm与6mm直径范围内有差异(P<0.0167)。B/F ratio术前为81.79%±1.87%，术后3mo为80.68%±2.23%(P<0.001)。

结论：白内障手术前后以角膜顶点和以瞳孔为中心的不同直径环上及区域内各项角膜屈光力参数会有一定的变化和差异，人工晶状体度数计算的K值选择及基于角膜特性的人工晶状体个体化选择时应予以考虑。     

Emergency cricothyroidotomy: an observational study to estimate optimal incision position and length

Background

A vertical incision is recommended for cricothyroidotomy when the anatomy is impalpable, but no evidence-based guideline exists regarding optimum site or length. The Difficult Airway Society guidelines, which are based on expert opinion, recommend an 80–100 mm vertical caudad to cephalad incision in the extended neck position. However, the guidelines do not advise the incision commencement point. We sought to determine the minimum incision length and commencement point above the suprasternal notch required to ensure that the cricothyroid membrane would be accessible within its margins.

Altered E-cadherin/beta-catenin expression in oral squamous carcinoma with and without nodal metastasis

OBJECTIVES: The aim of this study was to investigate the potential use of E-cadherin, a tumour-suppressor gene product involved in establishing cell-cell adhesion and one of its associated proteins, beta-catenin, as markers of nodal metastasis in oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS: Thirty invasive OSCCs in patients with (n = 19) and without (n = 11) nodal metastases, as confirmed on histopathologic examination of the resected regional lymph nodes (n = 30), were examined for E-cadherin and beta-catenin expression by immunohistochemistry. RESULTS: There was a highly significant association (P < 0.0001) between E-cadherin and beta-catenin expression and tumour differentiation by conventional Broders' grading of the whole tumour. Irrespective of the nodal status and invasive tumour front (ITF) grading score, however, loss of expression was recorded at the ITF in 28 (93%) of 30 tumours and 22 (73%) of 30 tumours stained for E-cadherin and beta-catenin respectively. CONCLUSION: The results of this study suggest an association between loss of expression of E-cadherin and beta-catenin and a lower degree of differentiation; however, their use as markers of nodal metastasis in OSCC appears unreliable.     

From the Cover: PNAS Plus: Climate change,pink salmon,and the nexus between bottom-up and top-down forcing in the subarctic Pacific Ocean and Bering Sea

Climate change in the last century was associated with spectacular growth of many wild Pacific salmon stocks in the North Pacific Ocean and Bering Sea, apparently through bottom-up forcing linking meteorology to ocean physics, water temperature, and plankton production. One species in particular, pink salmon, became so numerous by the 1990s that they began to dominate other species of salmon for prey resources and to exert top-down control in the open ocean ecosystem. Information from long-term monitoring of seabirds in the Aleutian Islands and Bering Sea reveals that the sphere of influence of pink salmon is much larger than previously known. Seabirds, pink salmon, other species of salmon, and by extension other higher-order predators, are tightly linked ecologically and must be included in international management and conservation policies for sustaining all species that compete for common, finite resource pools. These data further emphasize that the unique 2-y cycle in abundance of pink salmon drives interannual shifts between two alternate states of a complex marine ecosystem.Predator control of community structure and ecosystem function became a tenet of intertidal and nearshore marine ecology following early studies of Paine and others (1–3), yet with few exceptions (4, 5), until more recent times the idea has been less well appreciated for open oceans. Growing attention now is being paid to the overexploitation of pelagic species, particularly those at higher trophic levels currently and in the past, and effects on ocean ecosystems of the loss, or development, of top-down forcing (6–12).The prevailing view has long held that most biological change in ocean ecosystems, apart from human exploitation, is driven from the bottom up (13–16). One striking example that has been linked to bottom-up processes driven by climate change is the burgeoning abundance of wild Pacific salmon (Oncorhynchus spp.), and in particular pink salmon (Oncorhynchus gorbuscha), in the subarctic North Pacific Ocean and Bering Sea (SNPO/BS). Underpinning the notion initially were studies that found (i) strong coherence between decadal patterns in the Aleutian Low pressure system, which exerts a large influence over climate in the North Pacific Ocean, and patterns in salmon production across a broad region of the SNPO/BS (17, 18); (ii) decadal patterns in primary production that could be explained by the effect of the Aleutian Low pressure system on basin scale wind fields (19); and (iii) decadal patterns in zooplankton, squid, and pelagic fish production that also were correlated with meteorological forcing over the North Pacific Ocean and consistent with patterns in primary production (20). Thus, the general explanation for waxing and waning abundances of salmon over the record in the 20th century was that physical forcing by shifts in the strength and position of the Aleutian Low altered winds, ocean temperatures, and primary and secondary production to the benefit or detriment of salmon. A decadal scale oscillation in the Aleutian Low, now often referred to as the Pacific Decadal Oscillation (PDO) (21), has been linked to numerous physical and biological variability in the SNPO/BS in addition to salmon abundance (21–23).It was subsequently shown that salmon population responses and their relation to the PDO were out of phase between Alaska and the northwest coast of North America during much of the 20th century (24); that warm anomalies in coastal temperatures were associated with increased survival of salmon in Alaska; and that regional-scale variability in ocean temperature was a better predictor of salmon survival than large, basin-scale variability characterized by the PDO (25). A recent analysis from around the rim of the North Pacific Ocean found regional covariance in abundance of pink salmon, chum salmon (Oncorhynchus keta), and sockeye salmon (Oncorhynchus nerka) associated with the Aleutian Low, and with smaller scale spatially coherent, but regionally distinct, patterns in climate (26).Water temperature can be important to the early growth and survival of pink salmon fry directly by its effect on physiology and indirectly by its effect on the timing and development of zooplankton prey stocks in nursery areas, which commonly is advanced and greater in warmer years than in cooler years. In cooler springs, fry grow more slowly and a greater number die both from lack of food and from an increased susceptibility to predators (27, 28). For example, a conceptual model for Prince William Sound, Alaska, holds that, in years of abundant spring zooplankton, fry grow faster and remain longer in the shelter of inshore nurseries where they are protected from walleye pollock (Theragra chalcogramma) and Pacific herring (Clupea pallasii), two chief predators that remain offshore feeding primarily on swarms of large calanoid copepods and other macrozooplankton. In cooler years of lower zooplankton biomass inshore, fry grow more slowly, move offshore earlier, and suffer higher predation by pollock and herring due to spatial overlap, smaller size, and less alternative prey for those two predators (28).Although the relationship between climate and pink salmon survival is likely complex, fluctuations in abundance appear to be modulated in large measure directly and indirectly by the thermal environment in which a stock lives. Such a fundamentally bottom-up explanation is bolstered by observations of high growth and survival rates of pink salmon during the period of warmer ocean temperatures and population increase (29, 30), and at this time provides a more parsimonious explanation for population dynamics than would explanations invoking strictly top-down control across such a broad region. Now, however, several lines of evidence indicate that pink salmon themselves are having a large top-down influence on other salmon species, other upper trophic level pelagic species, plankton standing stocks, and by inference, the functioning of the open-ocean ecosystem in the SNPO/BS.     

前牙、双尖牙唇（颊）侧面开髓位置的临床研究

目的：了解前牙、双尖牙唇（颊）侧面开髓位置的临床应用的效果.方法：对264例前牙、双尖牙因楔形缺损或唇（颊）龋病并发牙髓炎、尖周炎的患者分为两组,试验组采用唇（颊）侧面位置进行开髓;对照组用传统方式（即舌或牙合面）开髓方法.结果：试验组,抗剪切力大,牙体不易劈折,成功率97.05％,对照组成功率30.40％ （P＜0.05）.结论：前牙、双尖牙唇（颊）侧面开髓位置只是一种针对前牙、双尖牙唇、颊面牙颈部深龋或楔形缺损引起牙髓及根尖感染、需要根管治疗的改进一种新开髓位置的方法,但不适应上颌第一双尖牙.     

合成生物学研究前沿的识别与趋势预测

目的：通过科学知识图谱的方法识别合成生物学研究前沿。方法应用参考文献共被引聚类、文献耦合聚类,通过VOSviewer绘制了合成生物学领域科学知识图谱,研究近两年文献对于聚类结构的改变。结果文献同被引分析生成7个聚类,文献耦合分析形成了32个聚类,近两年文献的加入改变了聚类原有的结构。结论耦合分析聚类比较适合研究前沿识别,合成生物工程、RNA表达、生物骨架、生物文库、生物组件等研究为该领域研究前沿。     

Intracellular claudin‐1 at the invasive front of tongue squamous cell carcinoma is associated with lymph node metastasis

Claudins are the major component of tight junctions, which form a primary barrier to paracellular diffusion and maintain cell polarity in normal epithelia and endothelia. In cancer cells, claudins play additional roles besides serving as components of the tight junctions, and participate in anoikis or invasion. Among the claudin family proteins, claudin‐1 has the most promising potential, both diagnostically and prognostically, in many types of cancers, including oral, gastric, liver, and colon cancers. However, conflicting results have been reported in relation to the degree of claudin‐1 expression and the prognosis, suggesting that the expression level of claudin‐1 alone is not sufficient to analyze the relationship between claudin‐1 and cancer progression. As endocytic trafficking of claudin‐1 has been reported in several epithelial cell types in vitro, we aimed to determine whether intracellular localization of claudin‐1 is the missing aspect between claudin‐1 and cancer. We investigated the expression of claudin‐1 in 83 tongue squamous cell carcinoma (TSCC) pathological specimens. Although the expression level of claudin‐1 based on immunohistochemistry was not associated with TSCC progression, within the high claudin‐1 expression group, the incidence of intracellular localization of claudin‐1 was correlated with cervical lymph node metastasis. In an in vitro experiment, claudin‐1 was constitutively internalized in TSCC‐derived cells. Motility of TSCC‐derived cells was increased by deficiency of claudin‐1, suggesting that the decrease in cell‐surface claudin‐1 promoted the cell migration. Therefore, intracellular localization of claudin‐1 at the invasion front may represent a promising diagnostic marker of TSCC.     

美皮康敷料对ICU压疮高风险患者皮肤保护的应用研究

目的探讨美皮康敷料在ICU压疮高风险患者皮肤保护中的有效性。方法选取2015年1-6月入住我科的压疮高风险的1 030例患者作为干预组,对患者预防性地使用美皮康敷料;2014年7-12月入住我科未进行敷料预防性保护的压疮高风险974例患者作为对照组。比较两组压疮的发生情况。结果干预组与对照组相比,压疮的发生率从3.49%下降到1.94%,差异具有统计学意义(P=0.032);干预组出现压疮的风险比为0.409[95%CI(0.211,0.793)]。结论美皮康敷料能够有效预防ICU压疮高风险患者压疮的发生。