The role of single immediate loading implant in long class IV Kennedy mandibular partial denture

Background: The treatment of long‐span Kennedy class IV considers a prosthodontic challenge. This study evaluated the integrity of principle abutments in long Kennedy class IV clinically and radiographically, when rehabilitated with conventional metallic partial denture as a control group and mandibular partial overdentures supported with single immediately loaded implant in symphyseal as a study group. Material and Methods: Twelve male patients were divided randomly allotted into two equal groups. First group patients received removable metallic partial denture, whereas in the second group, patients received partial overdentures supported with single immediately loaded implant in symphyseal region. The partial dentures design in both groups was the same. Long‐cone paralleling technique and transmission densitometer were used at the time of denture insertion, 3, 6, and 12 months. Gingival index, bone loss, and optical density were measured for principle abutments during the follow‐up. Results: A significant reduction in bone loss and density were detected in group II comparing with group I. Gingival index had no significant change (p‐value < 0.05). Conclusion: A single symphyseal implant in long span class IV Kennedy can play a pivotal role to improve the integrity of the principle abutments and alveolar bone support.     

颌面部神经内分泌癌2例临床病理分析

目的：报告2例罕见的颌面部神经内分泌癌,以便提高临床诊断和治疗水平。方法：分析2例颌面部神经内分泌癌的临床表现、组织学形态、免疫表型及预后,并对该疾病的相关文献进行复习。结果：2例颌面部原发神经内分泌癌患者,1例在术后半年发生局部复发并行第2次手术,另1例患者术后接受放疗,随访2年未见复发。结论：颌面部神经内分泌癌是一种罕见的高度恶性肿瘤,早期即可发生转移,预后差。     

鞍区大型肿瘤不同显微手术入路的疗效评估(附82例报道)

目的 探讨和评估大型鞍区肿瘤不同手术入路的疗效. 方法 福建医科大学附属漳州市医院神经外科和上海同济大学附属仁济医院神经外科自2004年1月至2012年1月采用不同的手术入路治疗鞍区大型肿瘤患者82例,其中双额底内侧入路32例,单鼻孔经蝶入路32例,扩大的翼点入路12例、单侧额下外侧入路6例,评估不同入路的结果和预后. 结果 本组肿瘤全切除66例,次全切除16例,其中经双额底内侧入路肿瘤全切除28例(87.5％),次全切4例;单鼻孔经蝶经入路肿瘤全切除26例(81.2％),次全切6例;扩大的翼点入路肿瘤全切除9例(75％),次全切3例;单侧额下外侧入路肿瘤全切除3例(50％),次全切3例.无手术死亡患者. 结论 鞍区大型肿瘤的切除可根据肿瘤类型选用经扩大的翼点入路或双额底内侧入路,单鼻孔经蝶入路主要适用于垂体腺瘤.     

Hyperbaric oxygen therapy improves cognitive functioning after brain injury

Hyperbaric oxygen therapy has been widely applied and recognized in the treatment of brain injury; however, the correlation between the protective effect of hyperbaric oxygen therapy and changes of metabolites in the brain remains unclear. To investigate the effect and potential mechanism of hy- perbaric oxygen therapy on cognitive functioning in rats, we established traumatic brain injury models using Feeney＇s free falling method. We treated rat models with hyperbaric oxygen therapy at 0.2 MPa for 60 minutes per day. The Morris water maze test for spatial navigation showed that the average escape latency was significantly prolonged and cognitive function decreased in rats with brain injury. After treatment with hyperbaric oxygen therapy for 1 and 2 weeks, the rats＇ spatial learning and memory abilities were improved. Hydrogen proton magnetic resonance spectroscopy analysis showed that the N-acetylaspartate/creatine ratio in the hippocampal CA3 region was sig- nificantly increased at 1 week, and the N-acetylaspartate/choline ratio was significantly increased at 2 weeks after hyperbaric oxygen therapy. Nissl staining and immunohistochemical staining showed that the number of nerve cells and Nissl bodies in the hippocampal CA3 region was significantly increased, and glial fibrillary acidic protein positive cells were decreased after a 2-week hyperbaric oxygen therapy treatment. Our findings indicate that hyperbaric oxygen therapy significantly im- proves cognitive functioning in rats with traumatic brain injury, and the potential mechanism is me- diated by metabolic changes and nerve cell restoration in the hippocampal CA3 region.     

Electrophysiological and morphological characterization of cells in superficial layers of rat presubiculum

The presubiculum (PrS) plays critical roles in spatial information processing and memory consolidation and has also been implicated in temporal lobe epileptogenesis. Despite its involvement in these processes, a basic structure–function analysis of PrS cells remains far from complete. To this end, we performed whole‐cell recording and biocytin labeling of PrS neurons in layer (L)II and LIII to examine their electrophysiological and morphological properties. We characterized the cell types based on electrophysiological criteria, correlated their gross morphology, and classified them into distinct categories using unsupervised hierarchical cluster analysis. We identified seven distinct cell types: regular‐spiking (RS), irregular‐spiking (IR), initially bursting (IB), stuttering (Stu), single‐spiking (SS), fast‐adapting (FA), and late‐spiking (LS) cells, of which RS and IB cells were common to LII and LIII, LS cells were specific to LIII, and the remaining types were identified exclusively in LII. Recorded neurons were either pyramidal or nonpyramidal and, except for Stu cells, displayed spine‐rich dendrites. The RS, IB, and IR cells appeared to be projection neurons based on extension of their axons into LIII of the medial entorhinal area (MEA) and/or angular bundle. We conclude that LII and LIII of PrS are distinct in their neuronal populations and together constitute a more diverse population of neurons than previously suggested. PrS neurons serve as major drivers of circuits in superficial (LII–III) entorhinal cortex (ERC) and couple neighboring structures through robust afferentation, thereby substantiating the PrS's critical role in the parahippocampal region. J. Comp. Neurol. 521: 3116–3132, 2013. © 2013 Wiley Periodicals, Inc.     

Clinical features and pathophysiological mechanism of the hemianoptic complication after the occipital transtentorial approach

Objective

To obtain detailed insight into neuro-ophthalmological characteristics and pathophysiology of hemianoptic complications after occipital transtentorial surgery.

Methods

We reviewed the cases of 14 patients surgically treated by the occipital transtentorial approach. Treated lesions included 6 posterior third ventricle tumors, including pineal and tectal lesions, 3 falco-tentorial meningiomas, and 5 superior cerebellar lesions. The surgeries were performed by the unilateral occipital transtentorial approach with patients in the prone position.

Results

Visual functions were preoperatively normal in all patients. After surgery, 11 patients (79%) showed hemianoptic complications detected by a confrontation test in the immediate postoperative period. The condition began to improve in the early postoperative days. The visual field recovered completely in 6 patients within 10 days, 2 patients recovered within 3 months, and 3 patients complained of permanent visual field defects. Optometric neuro-ophthalmic evaluation in the early postoperative period failed to detect complete homonymous hemianopsia, but homonymous inferior quadrantanopia and scotomatous defects were observed in 6 patients. These visual field defects were permanent in 3 patients. Postoperative MRI showed no morphological abnormality except these three patients. Atrophic change of the occipital lobe with preservation of striate cortex was associated with persistent visual field defects in two patients. Cerebral blood flow evaluation by single photon emission computed tomography suggested that temporary local hyperperfusion of the retracted occipital region when visual field defect was present.

Conclusion

Hemianoptic visual field defects can recover via inferior quadrantanopia or scotomatous defect. All of these defects are attributable to injury to the optic radiation as well to the occipital lobe. Hyperperfusion of the retracted occipital region may underlie the pathophysiology of hemianoptic complications after the occipital transtentorial approach.     

Loss of p53 cooperates with K‐ras activation to induce glioma formation in a region‐independent manner

Gliomas are recognized as a heterogeneous group of neoplasms differing in their location and morphological features. These differences, between and within varying grades of gliomas, have not been explained solely on the grounds of an oncogenic stimulus. Interactions with the tumor microenvironment as well as inherent characteristics of the cell of origin are likely a source of this heterogeneity. There is an ongoing debate over the cell of origin of gliomas, where some suggest a progenitor, while others argue for a stem cell origin. Thus, it is presumed that neurogenic regions of the brain such as the subventricular zone (SVZ) containing large numbers of neural stem and progenitor populations are more susceptible to transformation. Our studies demonstrate that K‐ras^G12D cooperates with the loss of p53 to induce gliomas from both the SVZ and cortical region, suggesting that cells in the SVZ are not uniquely gliomagenic. Using combinations of doxycycline‐inducible K‐ras^G12D and p53 loss, we show that tumors induced by the cooperative actions of these genes remain dependent on active K‐ras expression, as deinduction of K‐ras^G12D leads to complete tumor regression despite absence of p53. These results suggest that the interplay between specific combinations of genetic alterations and susceptible cell types, rather than the site of origin, are important determinates of gliomagenesis. Additionally, this model supports the view that, although several genetic events may be necessary to confer traits associated with oncogenic transformation, inactivation of a single oncogenic partner can undermine tumor maintenance, leading to regression and disease remission. GLIA 2013;61:1862–1872     

寒区陆航某部飞行人员多裂肌功能超声评价

目的应用高频定量超声方法比较寒区陆航某部飞行人员不同体位、不同军龄多裂肌收缩功能。方法医务人员携带设备在驻地将飞行人员分为A组(军龄>10年,n=22)与B组(军龄<10年,n=36),在L5平面定量超声测量放松体位、燕飞体位及bird dog体位3种体位的多裂肌厚度及截面积,并进行组间统计学分析。结果 3种体位中,多裂肌收缩最显著的为bird dog体位,其次为燕飞体位。B组多裂肌截面积收缩率明显高于A组(P<0.05);多裂肌厚度收缩率,两组间比较,差异无统计学意义(P>0.05)。结论多裂肌收缩功能可能会随飞行时间延长而降低。针对性加强多裂肌功能,可能会降低飞行人员腰背痛。超声可作为一种无创伤、无辐射、连续、便携、实时影像检查技术用于评估多裂肌功能。