Retinoid signaling in inner ear development: A "Goldilocks" phenomenon

Retinoic acid (RA) is a biologically active derivative of vitamin A that is indispensable for inner ear development. The normal function of RA is achieved only at optimal homeostatic concentrations, with an excess or deficiency in RA leading to inner ear dysmorphogenesis. We present an overview of the role of RA in the developing mammalian inner ear, discussing both how and when RA may act to critically control a program of inner ear development. Molecular mechanisms of otic teratogenicity involving two members of the fibroblast growth factor family, FGF3 and FGF10, and their downstream targets, Dlx5 and Dlx6, are examined under conditions of both RA excess and deficiency. We term the effect of too little or too much RA on FGF/Dlx signaling a Goldilocks phenomenon. We demonstrate that in each case (RA excess, RA deficiency), RA can directly affect FGF3/FGF10 signaling within the otic epithelium, leading to downregulated expression of these essential signaling molecules, which in turn, leads to diminution in Dlx5/Dlx6 expression. Non-cell autonomous affects of the otic epithelium subsequently occur, altering transforming growth factor-beta (TGFβ) expression in the neighboring periotic mesenchyme and serving as a putative explanation for RA-mediated otic capsule defects. We conclude that RA coordinates inner ear morphogenesis by controlling an FGF/Dlx signaling cascade, whose perturbation by deviations in local retinoid concentrations can lead to inner ear dysmorphogenesis.     

Light-activated Glue Can Heal Broken Hearts

Patching up holes in blood vessels and the heart＇s walls may become easier with a new light- activated glue.     

Elmer's Glue Contamination: A Brief Report

Abstract

The two commonly used methods of adhering tissue sections to slides are gelatin to the warm waterbath before cutting is started or smearing egg albumin onto the individual slide. Problems with both methods have led many histotechnologists to seek alternative ways of adhering tissue sections to the slides. Elmer's Glue, which we had used as an adhesive, was found to candida Sp. Non-human organism. It is effective if not used in staining fungi.     

Surgical Glue Aims to Speed Post-op Recovery

A new surgical glue, currently in testing, aims to greatly reduce or eliminate the need for postoperative drains (a procedure required to remove blood, pus, and other fluids that build up at the surgical site, following a surgery) in tummy tucks and other large flap procedures.     

Elmer's Glue Contamination: A Brief Report

Abstract

The two commonly used methods of adhering tissue sections to slides are gelatin to the warm waterbath before cutting is started or smearing egg albumin onto the individual slide. Problems with both methods have led many histotechnologists to seek alternative ways of adhering tissue sections to the slides. Elmer's Glue, which we had used as an adhesive, was found to candida Sp. Non-human organism. It is effective if not used in staining fungi.     

纤维蛋白胶在几丁质管修复面神经缺损中的应用

探讨纤维蛋白胶在神经缺损修复中的作用,寻求理想的外科修复方法。15只大耳白兔行单侧颞骨内面神经横断后,缺损为5mm,以几丁质管桥接,并用纤维蛋白胶粘合;神经束膜缝合组用0-0号线缝合,左侧作为正常对照。分别于术后3、5月行神经电生理测试。电生理结果显示随着修复时间的延长,再生面神经潜伏期(Incubation period,IP)逐渐缩短,动作电位波幅(Amplitude,AMP)逐渐增高,神经-肌肉传导速度(Nerve-muscleconduction velocity,NMCV)逐渐增快。几丁质管组和神经束膜缝合组再生神经与正常组比较,术后3月,其神经诱发电位潜伏期较长、动作电位波幅较低、神经-肌肉传导速度较慢,均为显著差异(P<0.01)。至术后5月,差异缩小,但仍有显著性(P<0.05)。同期内,几丁质管组和神经束膜缝合组再生神经相比较,差异无显著性(P>0.05)。实验结果提示:纤维蛋白胶联合几丁质管应用于面神经的修复具有简单、迅速、可靠的特点。     

纤维蛋白胶的制备及其在组织工程中的应用

对纤维蛋白胶的制备方法及其在组织工程中的应用进行了综述，并提出了有待进一步研究的问题。     

纤维蛋白胶的实验研究及临床应用

本文讨论了纤维蛋白胶的配方、工具和使用方法,并报告了6例临床经验。纤维蛋白原浓度需>40mg/ml,凝血酶浓度>500U/ml能立即凝固,<50U/ml,凝固时间>60秒。可根据不同目的选用不同的工具和配方。抑肽酶并非必要成份。通过6例初步临应用总结使用时的方法及注意事项。     

Middle ear meningiomas

Meningiomas arising in or presenting as middle ear lesions are relatively uncommon. This study retrospectively reviews the clinicopathologic features of six meningiomas arising in or extending into the middle ear. The patients comprise five women and one man ranging in age from 45 to 67 years (median, 55 years) at the time of surgery. Five tumors arose in the posterior fossa or temporal bone region and one tumor arose from the auditory canal itself. Three tumors arose on the right side and three on the left. Duration of symptoms before surgery involving the middle ear was known in five patients and ranged from 2 to 13 years (median, 10 years). Symptoms at presentation included gait or balance problems (n = 3), chronic otitis media (n = 2), diplopia (n = 2), hearing loss (n = 2), pain (n = 1), aural polyp (n = 1), and tinnitus (n = 1). Histologically, all six tumors resembled a syncytial (meningotheliomatous) meningioma. Psamomma bodies were noted in two tumors and two tumors demonstrated mild nuclear pleomorphism. None of the tumors demonstrated histologic features of atypical meningioma. Follow-up information was available in five patients. Four patients had prior surgery for removal of posterior fossa temporal bone meningiomas and developed recurrences involving the auditory canal 60 to 84 months after surgery. At the time of most recent follow-up examination, three patients were alive with evidence of tumor (65, 112, and 214 months), one patient was alive with no evidence of tumor (99 months), one patient died in the postoperative period of sepsis and pneumonia following resection of a middle ear recurrence (64 months), and one patient was lost to follow-up analysis. Meningiomas arising in or extending to the middle ear canal are unusual. They more commonly arise in woman and in most cases involve extension of intracranial/cranial tumors into the canal.     

Middle ear adenoma

Middle ear adenoma is a benign tumor of the middle ear that can have exocrine (mucinous) and/or neuroendocrine differentiation. Early authors described a separate tumor with predominantly neuroendocrine differentiation as a middle ear carcinoid tumor, but these are now known to be the same tumor. We review the literature of this tumor, including the clinical presentation, gross pathology, histopathology, immunohistochemistry, differential diagnosis, and prognosis.     

纤维蛋白胶存在的问题与相应的解决方法

分析了纤维蛋白胶存在的问题,如蛋白胶不同供体来源、成份来源、应用的简易性与有效性、止血功效局限、机械强度与纤溶抑制剂的选择等,并提出相应的解决方案.     

ZT胶作为门静脉栓塞材料的实验研究

目的探讨ZT胶行兔选择性门静脉栓塞（SPVE）的安全性及有效性。方法新西兰白兔24只，随机分为3组，A组为ZT胶：碘油（1：1）混合物组，B组为ZT胶：碘油（1：2）混合物组，对照组C组为碘油组。对各组门静脉左支进行SPVE，术后检测门静脉压力、肝转氨酶（ALT、AST）的变化，术后30d右肝重／全肝重、全肝重／体重。结果SPVE后门静脉压力、肝转氨酶呈一过性升高；栓塞后肝左叶萎缩、纤维化，肝右叶代偿性增生肥大．右肝重／全肝重B组为69．41％，而C组为39．00％。统计学分析显示，B组栓塞效果明显优于其他组（P〈0．05）。结论ZT胶：碘油（1：2）混合物是一种安全、有效的门静脉栓塞材料。