A novel mutation in the last exon of ATRX in a patient with α-thalassemia myelodysplastic syndrome

Abstract:  We describe a patient with acquired alpha-thalassemia myelodysplastic syndrome (ATMDS). A previously healthy 66-year-old man presented with hemoglobin of 9.3 g/dL, mean corpuscular volume 59 fL, and a bone marrow aspirate with increased erythroid precursors and hypolobulated megakaryocytes. Hemoglobin H inclusions were seen in most red cells after 1% brilliant cresyl blue supravital stain of the peripheral blood. At the molecular level, we identified of a novel mutation in the most 3' exon of the ATRX gene ( C GA→ T GA substitution in codon 2407) resulting in a premature termination codon (p.R2407X). This case provides further evidence for a link between ATRX mutations and ATMDS, and suggests a possible role for the conserved Q-box element in ATRX function.     

Airway troubles related to the double-lumen endobronchial tube in thoracic surgery

Purpose Several case reports indicate critical respiratory complications in relation to the double-lumen endobronchial tube (DLT). A prospective survey for the airway problems in using the DLT is presented. Methods One hundred adult patients undergoing thoracotomy for lung cancer were investigated. Tube malposition and airway obstruction were searched using a fiber-optic scope. The endobronchial cuff was positioned just below the trachcal carina while the trachea was intubated with a DLT (Rüsch). The distances of displacement, from the tracheal carina to the bronchial cuff, were measured during anesthesia using an epidural catheter, which had marks every 5 mm. The distances for correcting the tube position were measured at both the bronchial cuff and the level of the teethPaO₂,PaCO₂ andSPO₂ were also measured. Results Malposition (displacement over 5 mm from the correct position) was found in 42 patients, and 40 of them were in a withdrawal direction, occurring at the postural change and during one-lung ventilation, especially during manipulation of the lung hilum. Correcting distances at the level of the teeth were 15.3–3-times longer than those at the bronchial cuff. Airway deformities and gradual withdrawal of the bronchial cuff were found in association with surgical manipulation. Obstruction occurred at the tips of the tracheal tube in four patients and the bronchial tube in six patients, and at the tip of both in two patients. Hypoxemia (PaO₂<60 mmHg) occurred in four patients and hypercapnea (PaCO₂>60 mm Hg) in two patients. Conclusion Most of the DLT obstructions were associated with withdrawal malposition. Great attention to DLT displacement and airway deformity is advised.     

Coronary artery and saphenous vein graft remodeling: A review of histologic findings after various interventional procedures—part V

Catheter balloon angioplasty is a well accepted form of nonsurgical treatment of acutely and chronically obstructed coronary artery vessels. It is also the centerpiece for various new intervention techniques. Their morphologic effect on the site of obstruction has been termed “remodeling.” Part V of this six-part series focuses on remodeling effects of balloon angioplasty on obstructed young (≤ 1 year) and old (> 1 year) saphenous vein bypass grafts.     

阻塞性睡眠呼吸暂停综合征患者手术治疗的麻醉研究

目的：探讨阻塞性睡眠呼吸暂停综合征(obstructive sleep apnea syndrome，OSAS)患者手术治疗的麻醉处理。方法：72例OSAS患者手术前先正压通气治疗(continue positive airway pressure，CPAP)和评价上气道，55例患者经鼻或经口气管插管全身麻醉；在手术完毕患者完全清醒后拔除插管。结果：72例患者中，轻度16例、中度24例、重度32例。合并晨起高血压28例，心电图均有不同程度心肌缺血的表现；红细胞增多症12例；腭咽平面Ⅰ级9例、Ⅱ级24例、Ⅲ级的27例、Ⅳ级12例。术前3．5d行自动调压正压通气治疗(Auto—CPAP)，经口气管内插管48例，经鼻气管内插管6例，均无术中插管困难和术后高血压危象，呼吸道梗阻发生。结论：充分认识OSAHS患者全身麻醉的手术风险，术前CPAP治疗和上气道评估，术中正确处理、严格掌握气管内插管、术后拔管的时机，是保证OSAHS患者手术成功、麻醉安全的关键。     

The mechanical and morphological properties of bone beneath internal fixation plates of differing rigidity

The internal fixation of diaphyseal fractures by bone plates is a well recognized treatment. The normal physiological stress of bone is reduced by plates that cause a negative balance of bone-remodeling processes. Many investigators have shown that the degree of stress protection is dependent on the rigidity of the plates. It was the aim of this study to quantify mechanical and morphological changes at different locations in a plated diaphyseal bone as a function of differing plate rigidity. Two types of plates with the same size but different materials were used. The stainless steel plates had a modulus of elasticity and bending stiffness 3.2 times higher than the carbon fiber reinforced carbon plates. Both types of plates were applied to the intact right and left femora of six foxhounds for 6 months. The stiffer stainless steel plates led to a significantly higher bone loss and correspondingly greater loss of mechanical properties. These effects were greatest directly beneath the plate and less with increasing distance from the plate.     

Bone remodeling during the development of osteoporosis in paraplegia

Summary Osteoporosis developing during the first weeks after the onset of traumatic paraplegia was studied with cortical and cancellous samples of iliac crest and tibia of 14 patients, and compared to normals. We used a procedure of bone particle fractionation (according to degree of mineralization) that allowed us to establish a profile reflecting the metabolic remodeling of bone and to analyze the organic matrix of the newly synthesized tissue. In paraplegics, we observed a large increase in the proportion of little calcified bone in the cortical as well as in the cancellous bone. Based on amino acid analyses, we found a decreased number of hydroxyproline residues in the newly synthesized organic matrix from paraplegia bone resulting either from an alteration of the prolyl hydroxylation or from the presence of an excess of noncollagen polypeptides. These results, together with previously published data reporting increased urinary hydroxylproline and calcium kinetic parameters, suggest an enhanced rate of skeletal remodeling in acute paraplegia. When investigated 2 years after injury, the patterns of distribution approach that of normal subjects.     

Biochemical Markers of Bone Turnover in Camurati–Engelmann Disease: A Report on Four Cases in One Family

Moderate increases in ``classical' biochemical markers of bone turnover have been described only in some patients with Camurati–Engelmann disease. However, the determination of the following ``new' markers has not been previously performed: serum osteocalcin (BGP), bone alkaline phosphatase (BAP), carboxyterminal propeptide of type I procollagen (PICP), aminoterminal propeptide of type I procollagen (PINP), tartrate-resistant acid phosphatase (TRAP), telopeptide carboxyterminal of type I collagen (ICTP), urinary pyridinoline (PYR), crosslinked N-telopeptides of type I collagen (NTX), and Crosslaps (CL). Such a determination may improve the evaluation of the disease activity. To evaluate the usefulness of biochemical markers of bone turnover reflecting Camurati–Engelmann disease activity we measured the levels of all these markers in four affected patients. The results were compared with bone scintigraphic indices of disease activity. Except for PICP and TRAP, bone formation and resorption markers were abnormal in all patients and were related to bone scan indices of disease activity. Among the markers of bone formation PINP, BAP, and BGP showed the highest values, whereas NTX and CL were the most sensitive markers of bone resorption. These results suggest that the determination of NTX or CL, and PINP or either BAP and BGP, associated with bone scan evaluation, provides the best assessment of Camurati–Engelmann disease activity. Received: 14 June 1996 / Accepted: 31 December 1996     

转化生长因子-β在哮喘气道炎症与重塑中的作用

Transforming growth factor-β(TGF-β) was reported to be increased in asthma in some studies. Accumulation of TGF-β in airway promotes smooth muscle cell mitogenesis and hyperplasia, and in-duces fibroblast and myofibroblast and smooth muscle proliferation as well as increase in protein synthesis in connective tissue(such as collagen deposition on the reticular basement membrane). The autocrine induction of collagen expression by smooth muscle may contribute to the thickening of the reticular basement membrane, irre-versible f‘throsis and remodeling seen in the airways in some asthmatics. TGF-β is considered to be a major fi-brogenic cytokine. It can increase smooth muscle mass and lead to severe bronchial obstruction in an asthma at-tack.     

STUDY OF MORPHOLOGICAL CHANGES OF HEART IN VIRAL MYOCARDITIS CAUSED BY REPETITIVE INFECTION OF CVB3m

Objective To investigate the morphological changes of heart in viral myocarditis caused by repetitive infection of CVB3m. Methods 4-week-old mice were infected four times intraperitoneally with a timedependent dose and killed at the 10th, 30th and 60th day after the final infection respectively, then we examined the heart changes and collagen hyperplasia by HE, VG stain and 1HC. Results Heart damage appeared very serious at the tenth day, even there were small necrotic foci at the day of 30th, but we could not see any injury of heart 2 months later after final infection. Collagen turned up at the tenth day and there was much more collagen in heart and increased PCVA, CVF index at the sixtieth day. The 1HC of collagen demonstrated the collagen I hyperplasia was much obvious compared to collagen Ⅲ. Conclusion It strongly indicated that repetitive infection of CVB3m could lead to heart fibrosis and ventricular remodeling, which resulted in decreased systolic and diastolic function of heart.     

麝香酮对易卒中型肾血管性高血压大鼠血浆内皮素和脑血管重塑的影响

目的观察麝香酮对易卒中型肾血管性高血压大鼠(RHRSP)血浆内皮素(ET)和脑动脉结构改变的影响。方法雄性RHRSP自术后第9周始分成两组:高血压组(n=12)和麝香酮治疗组(n=12),并以年龄、性别、数量相同的正常假手术组作对照,测量收缩压(SBP)和血浆ET含量,显微镜下观察血管形态改变,计算机图像分析血管外径、中膜厚度、管腔内径、中膜面积和壁腔比。结果12周时麝香酮组的SBP、ET水平比高血压组低(P<0.05)。镜下观察发现麝香酮组血管形态损害比高血压组轻。麝香酮组血管外径、血管内径、管壁厚度均大于高血压组(P<0.05),壁腔比则小于高血压组(P<0.05)。大脑中动脉平滑肌细胞面积较高血压组大,但两者间差异无统计学意义(P>0.05)。结论麝香酮治疗可轻度降低RHRSP的SBP和血浆ET水平,并能一定程度上改善其血管重塑。