急性T淋巴细胞白血病细胞系JM分泌抑制因子在体外对T细胞凋亡及细胞周期的影响

目的　研究急性 T淋巴细胞白血病细胞系 JM分泌的抑制因子 (TL SFJM)在体外对 T细胞凋亡及细胞周期的影响 .方法　以 TL SFJM作用于有丝分裂原 PHA、蛋白激酶 C(PKC)活化剂 PMA和同种异体抗原 (alloantigen)活化的人或小鼠 T细胞 ,应用流式细胞仪检测细胞凋亡及细胞周期 .结果　 TL SFJM在体外可诱导 PHA/IL - 2活化的小鼠胸腺细胞的凋亡 .TL SFJM在体外可诱导 alloantigen活化的人外周血单个核细胞 (PBMC)的凋亡 ,且把细胞周期阻遏在 G1期 .TL SFJM对 PMA诱导的人 PBMC活化抗原 CD2 5的表达无明显影响 ,也不引起凋亡 .结论　 TL SFJM在体外可诱导 PHA、alloantigen活化的 T细胞凋亡 .     

Bidirectional Ultrasound Elastographic Imaging Framework for Non-invasive Assessment of the Non-linear Behavior of a Physiologically Pressurized Artery

Studies of non-destructive bidirectional ultrasound assessment of non-linear mechanical behavior of the artery are scarce in the literature. We hereby propose derivation of a strain–shear modulus relationship as a new graphical diagnostic index using an ultrasound elastographic imaging framework, which encompasses our in-house bidirectional vascular guided wave imaging (VGWI) and ultrasound strain imaging (USI). This framework is used to assess arterial non-linearity in two orthogonal (i.e., longitudinal and circumferential) directions in the absence of non-invasive pressure measurement. Bidirectional VGWI estimates longitudinal (μ_L) and transverse (μ_T) shear moduli, whereas USI estimates radial strain (?_r). Vessel-mimicking phantoms (with and without longitudinal pre-stretch) and in vitro porcine aortas under static and/or dynamic physiologic intraluminal pressure loads were examined. ?_r was found to be a suitable alternative to intraluminal pressure for representation of cyclic loading on the artery wall. Results revealed that μ_T values of all samples examined increased non-linearly with ε_r magnitude and more drastically than μ_L, whereas μ_L values of only the pre-stretched phantoms and aortas increased with ?_r magnitude. As a new graphical representation of arterial non-linearity and function, strain–shear modulus loops derived by the proposed framework over two consecutive dynamic loading cycles differentiated sample pre-conditions and corroborated direction-dependent non-linear mechanical behaviors of the aorta with high estimation repeatability.     

Removal of forearm plate leads to a high risk of refracture: decision regarding implant removal after fixation of the forearm and analysis of risk factors of refracture

Introduction

Plate fixation is the gold standard for the treatment of forearm fractures at present, and whether or not to remove the implant after bone union remains controversial. This study demonstrated some cases of refracture in adult forearm fractures after bone union and discussed the risk factors for decision-making regarding implant removal.

Methods

We reviewed patients with forearm diaphyseal fractures (including the radius, ulna, or both bones) who received open reduction and internal fixation (ORIF) from January 2008 to May 2011 in our institute. Fracture type was classified according to the AO/OTA system. All patients were fixed with a 3.5-mm dynamic compression plate. The patients were divided into two main groups: group A received implant removal after bone union, and group B retained the implant.

Results

There were 122 patients (170 bones) included in this study (40 females and 82 males). In group A, 7/51 patients (8/62 bones; 12.9 %) had refracture. As classified by the AO/OTA classification, one patient was classified as type A1, one patient as type A2, two patients as type A3, and three patients as type B3. All patients suffered refracture without high-energy trauma. In group B, the refracture rate was 2.77 %, and all were caused by high-energy trauma. Patients with refracture had a shorter time interval between ORIF and implant removal. The possible risk factors of refracture in this study included a wedge bone defect on plain film, implant removal performed after less than 18 months, and AO/OTA type B fracture.

Conclusion

The incidence of refracture was significantly lower in the group that retained the implant. Routine implant removal after bone union in adult forearm fractures is not recommended due to the higher refracture rate.     

近视眼与正常眼Q值的分析

目的探讨Q值及其与屈光状态的关系,为角膜屈光手术的个体化切削提供理论依据。方法随机选取150只近视及近视散光眼和30例正视眼,近视眼根据其屈光状态分为低、中、高3组,各组的散光度数均在-2.00D以下。分别测量角膜地形图和屈光度,将所得到的结果进行统计学分析。结果平均Q值大约为-0.172,其中低度近视组为-0.136,中度近视组为-0.191,高度近视组为-0.192,正视眼组为-0.168。低度近视组和中度近视组（p=0.117,p〉0.05）,低度近视组和高度近视组（p=0.115,p〉0.05）以及中度近视组和高度近视组（p=0.983,p〉0.05）之间的Q值间差异无统计学意义。Q值与球镜度数的相关分析（r=0.137,p=0.047〈0.05）,说明Q值与球镜度数存在线性相关关系。而Q值与柱镜的相关分析显示两者无相关性（r=-0.025,p=0.383〉0.05）。结论影响Q值的主要因素为球镜的度数,两者呈正相关,对Q值的研究还需要更大样本量的病例,以期获得更详尽的数据。     

Dissociation of function between the dorsal and the ventral hippocampus in spatial learning abilities of the rat: a within-subject, within-task comparison of reference and working spatial memory

Lesions restricted to the dorsal, but not the ventral, hippocampus severely impair the formation of spatial memory. This dissociation was first demonstrated using the water maze task. The present study investigated whether the dorsal and the ventral hippocampus are involved differentially in spatial reference and spatial working memory using a four-baited/four-unbaited version of the eight-arm radial maze task. This test allows the concurrent evaluation of reference and working memory with respect to the same set of spatial cues, and thereby enables a within-subjects within-task comparison between the two forms of memory functions. Rats with N-methyl-d-aspartic acid-induced excitotoxic lesions of the dorsal hippocampus, ventral hippocampus or both were compared with sham and unoperated controls. We showed that dorsal lesions were as effective as complete lesions in severely disrupting both reference and working spatial memory, whereas rats with ventral lesions performed at a level comparable with controls. These results lend further support to the existence of a functional dissociation between the dorsal and the ventral hippocampus, with the former being preferentially involved in spatial learning.     

An efficient speckle tracking algorithm for ultrasonic imaging

An efficient speckle tracking algorithm is proposed for motion estimation in ultrasonic imaging. Speckle tracking involves a matching process and a searching process. The matching process of the proposed algorithm is based on a Block Sum Pyramid algorithm that significantly reduces the computational complexity while maintaining the same accuracy as the conventional sum of absolute difference approach. The searching process, on the other hand, is based on a multilevel search strategy rather than the full-search strategy used by most conventional tracking methods. Both simulated speckle images and clinical breast images were used to test the performance of the proposed algorithm. The results show that the computation efficiency is improved by up to a factor of five over the conventional approach. The improved efficiency enables real-time or near-real-time implementation of motion estimation in ultrasonic imaging, which is particularly beneficial in areas such as blood flow estimation, elasticity imaging, speckle image registration, and strain compounding.     

Acquired atlantoaxial instability in children with spastic cerebral palsy

The development of nontraumatic atlantoaxial instability in children with spastic cerebral palsy has not been reported. The authors present three patients with severe spastic quadriplegia who developed C1-C2 instability and cervical myelopathy at mean age 12.6 years. These patients demonstrated a similar clinical picture with symptoms attributed to cervical myelopathy in varied severity including apneic episodes, opisthotonus, alteration in muscle tone, torticollis, respiratory problems, hyperreflexia, and bradycardia. Patient 1 was scheduled for surgery but died due to an apneic episode. Patient 2 refused surgery and has been followed for 3 years while his neurologic condition remains unchanged. Patient 3 underwent occipitocervical decompression and fusion, recovered neurologically, and resumed his previous functional skills. Patients demonstrating considerable functional deterioration or insidious change in their established neurologic status should undergo detailed screening to rule out developing upper cervical instability. Early surgical intervention consisting of spinal decompression and fusion may prevent the development of myelopathy.     

Slotted acetabular augmentation in the treatment of painful residual dysplastic hips in adolescents and young adults

Background/Purpose: This study retrospectively evaluated the benefits and prognostic factors of slotted acetabular augmentation (SAA) used for treating painful residual or neglected dysplastic hips in adolescents and young adults. Methods: Sixteen hips in 15 patients underwent SAA at an average age of 14.4 years. The radiologic and functional outcomes were reviewed after an average follow-up of 6.6 years. Results: All the patients obtained marked alleviation of pain (p < 0.05). Harris hip score (HHS) was improved from 74.7 to 92.7 on average (p < 0.05). Postoperative center-edge angle, Sharp's angle, c/b ratio and femoral head coverage showed significant improvement (p < 0.01). Among the radiographic parameters, only the postoperative measurement of the femoral head coverage was significantly correlated with improvement of HHS (p < 0.05). Detectable progression of osteoarthritis, from grade III to IV, was found in one patient 12 years after surgery. None of the hips required conversion to joint replacement. There were no surgical complications. Three-dimensional computed tomography showed that the grafts remained intact and provided congruent coverage at the latest follow-up, and none of them required arthroplasty. Conclusion: The major benefit of SAA was to alleviate hip pain by increasing load-bearing area. This benefit was not sensitive to preoperative radiographic parameters. There were no postoperative complications. Compared with other complex reconstructive acetabuloplasty procedures, SAA is a simple, safe and effective pain-reducing procedure for symptomatic dysplastic hips in adolescents and young adults.     

Activation of ROS/NF-κB and Ca/CaM kinase II are necessary for VCAM-1 induction in IL-1β-treated human tracheal smooth muscle cells

Histone acetylation regulated by histone acetyltransferases (HATs) and histone deacetylases (HDACs) plays a critical role in the expression of inflammatory genes, such as vascular cell adhesion molecule-1 (VCAM-1). Oxidative processes have been shown to induce VCAM-1 expression. Here, we investigated the mechanisms underlying IL-1β-induced VCAM-1 expression in human tracheal smooth muscle cells (HTSMCs). Our results showed that IL-1β enhanced HTSMCs-monocyte adhesion through up-regulation of VCAM-1, which was inhibited by pretreatment with selective inhibitors of PKCα (Gö6976), c-Src (PP1), NADPH oxidase [diphenylene iodonium (DPI) and apocynin (APO)], intracellular calcium chelator (BAPTA/AM), PI-PLC (U73122), CaM (calmidazolium chloride), CaM kinase II (KN62), p300 (garcinol), NF-κB (Bay11-7082), HDAC (trichostatin A), and ROS scavenger [N-acetyl-l-cysteine (NAC)] or transfection with siRNAs of MyD88, PKCα, Src, p47^phox, p300, and HDAC4. Moreover, IL-1β stimulated NF-κB and CaMKII phosphorylation through MyD88-dependent PI-PLC/PKCα/c-Src/ROS and PI-PLC/Ca²⁺/CaM pathways, respectively. Activation of NF-κB and CaMKII may eventually lead to the acetylation of histone residues and phosphorylation of histone deacetylases. These findings suggested that IL-1β induced VCAM-1 expression via these multiple signaling pathways in HTSMCs. Blockade of these pathways may reduce monocyte adhesion via VCAM-1 suppression and attenuation of the inflammatory responses in airway diseases.