Left–right asymmetry: cilia stir up new surprises in the node

Cilia are microtubule-based hair-like organelles that project from the surface of most eukaryotic cells. They play critical roles in cellular motility, fluid transport and a variety of signal transduction pathways. While we have a good appreciation of the mechanisms of ciliary biogenesis and the details of their structure, many of their functions demand a more lucid understanding. One such function, which remains as intriguing as the time when it was first discovered, is how beating cilia in the node drive the establishment of left–right asymmetry in the vertebrate embryo. The bone of contention has been the two schools of thought that have been put forth to explain this phenomenon. While the ‘morphogen hypothesis’ believes that ciliary motility is responsible for the transport of a morphogen preferentially to the left side, the ‘two-cilia model’ posits that the motile cilia generate a leftward-directed fluid flow that is somehow sensed by the immotile sensory cilia on the periphery of the node. Recent studies with the mouse embryo argue in favour of the latter scenario. Yet this principle may not be generally conserved in other vertebrates that use nodal flow to specify their left–right axis. Work with the teleost fish medaka raises the tantalizing possibility that motility as well as sensory functions of the nodal cilia could be residing within the same organelle. In the end, how ciliary signalling is transmitted to institute asymmetric gene expression that ultimately induces asymmetric organogenesis remains unresolved.     

进展期胃癌的脾门淋巴结转移相关因素的研究

目的:探讨进展期胃癌脾门淋巴结(10组)转移的相关临床病理因素.方法:回顾分析了(2008-2011年)75例胃癌根治术伴10组淋巴结切除的进展期胃癌病例.分析了临床病理学因素和10组淋巴结转移的相关性.结果:本研究结果提示10组淋巴结转移的阳性率为52％.胃下部癌的转移率(20％)相对较低(P=0.000),大弯侧肿瘤的转移率高达76.2％.病灶的侵润深度及病理TNM分期与10组淋巴结阳性率密切相关,组织学类型或分化程度与10组淋巴结转移无统计学相关.病灶小于3 cm病例的10组淋巴结转移的阳性率为0％,而大于9 cm或Borrmann-Ⅳ的肿瘤患者的10组淋巴结转移的阳性率为100％.结论:10组淋巴结转移的高危因素包括:1.中上部胃癌;2.肿瘤位于胃大弯侧;3.大于3 cm; 4.侵达胃壁浆膜层.含以上高危因素的进展期胃癌根治手术中,建议常规行术中快速冰冻检查10组淋巴结是否存在转移;含2个以上高危因素的进展期胃癌建议行脾切除术,或如果技术条件具备应行保留脾的10组淋巴结清扫术以便最终获得R0切除.     

淋巴结转移阴性的胃癌患者临床病理特征及生存探讨

目的:探讨淋巴结转移阴性胃癌患者的临床病理特征以及预后影响因素。方法:收集2000年1月至2009年1月我院收治的胃癌患者325例,其中经病理检查显示淋巴结转移阴性的105例患者作为阴性组(LN-组),另229例阳性患者作为阳性组(LN+组),比较两组的临床病理特征及临床预后。结果:LN-组的肿瘤直径、浸润深度及术后化疗与LN+组比较差异显著(P0.05);LN-组的5年生存率为76.2%,显著高于LN+组的43.2%(P0.05)。未透浆膜的LN-患者3年、5年生存率显著高于浸透浆膜者,术后化疗的LN-患者5年生存率显著高于未化疗者(P0.05),肿瘤直径5 cm的LN-患者3、5年生存率显著高于≥5 cm者(P0.05)。单因素分析显示浸润深度、肿瘤大小及术后化疗与LN-胃癌患者的预后具有密切关系(P0.05)。COX多因素分析显示浸润深度是影响LN-胃癌患者临床预后的独立因素(P0.05)。结论:淋巴结转移阴性胃癌患者的病灶多位于中下部,男性多于女性,发病年龄多在60岁以内,肿瘤直径多不超过5 cm,浸润深度多未浸透浆膜,临床预后优于淋巴结转移阳性胃癌患者,浸润深度是影响淋巴结转移阴性胃癌患者临床预后的独立因素。     

Focus: The Aging Brain: Neurocardiovascular Instability and Cognition

Neurocardiovascular instability (NCVI) refers to abnormal neural control of the cardiovascular system affecting blood pressure and heart rate behavior. Autonomic dysfunction and impaired cerebral autoregulation in aging contribute to this phenomenon characterized by hypotension and bradyarrhythmia. Ultimately, this increases the risk of falls and syncope in older people. NCVI is common in patients with neurodegenerative disorders including dementia. This review discusses the various syndromes that characterize NCVI icluding hypotension, carotid sinus hypersensitivity, postprandial hypotension and vasovagal syncope and how they may contribute to the aetiology of cognitive decline. Conversely, they may also be a consequence of a common neurodegenerative process. Regardless, recognition of their association is paramount in optimizing management of these patients.     

VEGF-A在食管鳞状细胞癌中的表达及临床意义

目的:探讨血管内皮生长因子A(VEGF-A)在食管鳞状细胞癌中的表达及临床意义。方法:收集2009年1月-2010年12月收治的45例食管鳞状细胞癌患者临床资料及病理标本,应用免疫组织化学法检测肿瘤组织VEGF-A表达及微淋巴管密度(MLVD),分析VEGF-A表达与食管鳞癌患者临床病理资料、MLVD及与患者生存期限的关系。结果:1有淋巴结转移的患者VEGF-A表达阳性率为66.67%,明显高于无淋巴结转移患者的38.10%(P0.05);2 VEGF-A阳性食管鳞状细胞癌患者MLVD为(8.35±2.45)明显高于阴性患者的(5.32±1.44),(P0.05);3VEGF-A阳性食管鳞状细胞癌患者3年存活率为41.67%明显低于阴性患者的61.90%(P0.05)。结论:VEGF-A表达在确定早期食管鳞状细胞癌淋巴结转移方面具有一定的应用价值,可以作为评价预后的有效指标。     

跗骨窦入路切开复位内固定与外侧"L"形入路切开复位内固定治疗跟骨骨折的疗效比较研究

目的:比较跗骨窦入路切开复位内固定与外侧"L"形入路切开复位内固定治疗跟骨骨折的疗效。方法:选取2016年10月到2017年6月期间川北医学院附属医院收治的86例跟骨骨折患者,根据随机数字表法分为对照组和观察组,两组均为43例。对照组采用外侧"L"形入路切开复位内固定进行治疗,观察组采用跗骨窦入路切开复位内固定进行治疗。比较两组患者的手术时间、住院时间、骨折愈合时间、踝-后足功能优良率、视觉模拟评分法(VAS)、B?hler角、Gissane角和术后并发症发生率。结果:两组患者的手术时间和骨折愈合时间比较无统计学差异(P0.05),而观察组患者的住院时间短于对照组(P0.05)。观察组患者术后踝-后足功能优良率高于对照组(P0.05)。在术前和术后12个月时,两组患者的VAS评分、Gissane角、B?hler角比较无统计学差异(P0.05),术后12个月时两组患者的VAS评分均明显低于术前,B?hler角及Gissane角明显高于术前(P0.05)。观察组患者术后并发症发生率低于对照组(P0.05)。结论:跗骨窦入路和外侧"L"形入路切开复位内固定均可有效治疗跟骨骨折,但跗骨窦入路可更有效地改善踝-后足功能,且住院时间短、术后并发症发生率更低。     

混合甲醛固定液固定大肠癌淋巴结标本的最佳免疫组化效果研究

目的:探讨混合甲醛固定液固定大肠癌淋巴结标本的最佳免疫组化效果。方法:采用不同pH值(6.0、7.0、8.0)的混合甲醛固定液对39枚大肠癌淋巴结标本进行不同时间(6 h、6 h-12 h、1 d-7 d)的固定处理。以细胞角蛋白20(CK20)为目标抗原,运用OIympusdp 70图像采集分析仪抽选出混合甲醛固定液最佳免疫组化染色的pH值及固定时间。结果:经pH值为7.0混合甲醛固定液处理后,阳性率为92.31%,高于经pH值为6.0、8.0的混合甲醛固定液处理后的76.92%、74.36%,且经pH值为7.0、8.0处理后的阳性率比较有统计差异(P0.05)。混合甲醛固定液的固定时间在6 h-12 h时的阳性率为94.87%,高于固定时间为6 h、1 d-7 d处理的30.77%、76.92%(P0.05)。结论:对于大肠癌淋巴结标本,以CK20为目标抗原,选择pH值为7.0的混合甲醛固定液固定6 h-12 h能够得到质量较佳的免疫组化染色效果。     

Prediction of lymph node metastasis in oral squamous cell carcinoma based on protein profile

Objective: Lymph node metastasis leads to high mortality rates of oral squamous cell carcinoma (OSCC). However, it is still controversial to define clinically negative neck (cN0) and positive neck (cN1-3).

Methods: We retrieved candidate biomarkers identified by proteomic analysis in OSCC from published works of literature. In training stage, immunohistochemistry (IHC) analysis was used to determine the expression of proteins and logistic regression models with stepwise variable selection were used to identify potential factors that might affect lymph node metastasis and life status. Furthermore, the prediction model was validated in validating stage.

Results: We screened eight highly expressed proteins related to lymph node metastasis in OSCC and found that the expression levels of SOD2, BST2, CAD, ITGB6, and PRDX4 were significantly elevated in patients with lymph node metastasis compared to the patients without lymph node metastasis. Furthermore, in training and validating stages, the prediction model base on the combination of CAD, SOD2 expression levels, and histopathologic grade was developed and validated in patients with OSCC.

Conclusions: Our findings showed that the developed model well predicts the lymph node metastasis and life status in patients with OSCC, independent of TNM stage.     

Bioimaging of multiple elements by high‐resolution LA‐ICP‐MS reveals altered distribution of mineral elements in the nodes of rice mutants

Inter‐vascular transfer in rice (Oryza sativa) nodes is required for delivering mineral elements to developing tissues, which is mediated by various transporters in the nodes. However, the effect of these transporters on distribution of mineral elements in the nodes at a cellular level is still unknown. Here, we established a protocol for bioimaging of multiple elements at a cellular level in rice node by laser ablation‐inductively coupled plasma‐mass spectrometry (LA‐ICP‐MS), and compared the mineral distribution profile between wild‐type (WT) rice and mutants. Both relative comparison of mineral distribution normalized by endogenous ¹³C and quantitative analysis using spiked standards combined with soft ablation gave valid results. Overall, macro‐nutrients such as K and Mg were accumulated more in the phloem region, while micro‐nutrients such as Fe and Zn were highly accumulated at the inter‐vascular tissues of the node. In mutants of nodal Zn transporter OsHMA2, Zn localization pattern in the node tissues did not differ from that of WT; however, Zn accumulation in the inter‐vascular tissues was lower in uppermost node I but higher in the third upper node III compared with the WT. In contrast, Si deposition in the mutants of three nodal Si transporters Lsi2, Lsi3 and Lsi6 showed different patterns, which are consistent with the localization of these transporters. This improved LA‐ICP‐MS analysis combined with functional characterization of transporters will provide further insight into mineral element distribution mechanisms in rice and other plant species.     

1064 nm acoustic resolution photoacoustic microscopy

Photoacoustic imaging is a noninvasive imaging technique having the advantages of high‐optical contrast and good acoustic resolution at improved imaging depths. Light transport in biological tissues is mainly characterized by strong optical scattering and absorption. Photoacoustic microscopy is capable of achieving high‐resolution images at greater depth compared to conventional optical microscopy methods. In this work, we have developed a high‐resolution, acoustic resolution photoacoustic microscopy (AR‐PAM) system in the near infra‐red (NIR) window II (NIR‐II, eg, 1064 nm) for deep tissue imaging. Higher imaging depth is achieved as the tissue scattering at 1064 nm is lesser compared to visible or near infrared window‐I (NIR‐I). Our developed system can provide a lateral resolution of 130 μm, axial resolution of 57 μm, and image up to 11 mm deep in biological tissues. This 1064‐AR‐PAM system was used for imaging sentinel lymph node and the lymph vessel in rat. Urinary bladder of rat filled with black ink was also imaged to validate the feasibility of the developed system to study deeply seated organs.