Myocardial infarct size quantification by MR imaging early after coronary artery occlusion in dogs

The feasibility of using magnetic resonance (MR) imaging to estimate myocardial infarct size was explored in an in vitro model using only the inherent differences in contrast between infarcted and noninfarcted myocardium. Eight dogs underwent coronary occlusion; their hearts were removed 6 hours later. Estimates of T2 for normal and infarcted myocardium were derived from MR images. Infarct size was quantified anatomically using triphenyltetrazolium-chloride (TTC) staining and compared with MR estimates. The T2 values derived from the images clearly discriminated between infarcted (126 +/- 22 msec) and normal myocardium (88 +/- 10 msec, P less than .05), providing images with good contrast between normal and infarcted myocardium. Comparable differences in T2 values were also noted from spectrometric determinations. Estimates of infarct size by MR imaging compared well with TTC estimates (r = 0.98) over a wide range of infarct sizes from 3% to 29% of the left ventricular mass. These results suggest the potential for in vivo quantification of infarct size based on the inherent contrast difference between infarcted and normal myocardium.     

急性失代偿性心力衰竭患者血清肌钙蛋白T水平检测的价值

目的：研究肌钙蛋白T的水平变化在急性失代偿性心力衰竭患者预后的价值。方法：选取急诊重症监护室收治的68例急性失代偿性心力衰竭患者,按照cTnT的水平分为cTnT阳性组（27例）和cTnT阴性组（41例）。观察两组患者室性期前收缩发生率、APACHEⅡ评分、在ICU入住时间、住院时间、住院病死率、随访出院后6个月内再入院率及6个月死亡率。结果：两组治疗期间利尿剂、扩血管药物使用、多巴胺和（或）多巴酚丁胺的使用和两组患者6个月随访期间死亡率比较差异无统计学意义（P〉0.05）。入院时APACHEⅡ评分、在ICU入住时间、住院时间、住院病死率及出院后6个月内再入院率比较均显示差异有统计学意义（P〈0.05）。结论：肌钙蛋白T水平是与治疗无关的危险因素之一。伴有肌钙蛋白T升高的急性失代偿性心力衰竭患者有较高的室性期前收缩发生率、较长的住院时间、短期预后差,监测cTnT水平对急性失代偿性心力衰竭患者的病情评估和短期预后有重要作用。     

Massive hemoptysis: control by embolization of the thyrocervical trunk

A case of recurrent hemoptysis following bronchial artery embolization is presented. The bleeding was successfully controlled by embolization of the thyrocervical trunk.     

Effects of Porcine Circovirus Type 2 (PCV2) Maternal Antibodies on Experimental Infection of Piglets with PCV2

To determine the effects of porcine circovirus type 2 (PCV2) maternal antibodies on and response to experimental PCV2 infection, 24 piglets were divided into four groups on the basis of the enzyme-linked immunosorbent assay titers of PCV2 maternal antibodies: group A (n = 6; sample/positive [S/P] ratio, <0.2), group B (n = 5; S/P ratio, >0.2 to <0.5), and groups C (n = 8) and D (n = 5) (S/P ratio, >0.5). Piglets in groups A, B, and C were inoculated with PCV2 at day 0 and challenged with PCV2 at day 42. Group D piglets were not exposed to PCV2 at day 0 but were challenged at day 42. Before challenge, seroconversion to PCV2 antibodies occurred in fiveofsix group A piglets, and the antibody level rose above the cutoff level in oneoffive group B piglets. Viremia was detected in fiveofsix, fouroffive, and twoofeight pigs in groups A, B, and C, respectively. After challenge, PCV2 DNA was detectable from 7 to 21 days postchallenge in the sera from sixofsix, fouroffive, threeofeight, and fiveoffive pigs in groups A, B, C, and D, respectively. The results indicated that protection against PCV2 infection conferred by maternal antibodies is titer dependent: higher titers are generally protective, but low titers are not.     

Thoracoscopic lung biopsy.

Progress in instrumentation and techniques developed for laparoscopic surgery have paved the way for a resurgent interest in thoracoscopic procedures. Traditional thoracoscopy was limited by access, restricted visualization, and surgical devices. Recent cases provided an opportunity to successfully perform thoracoscopic pulmonary wedge excisions using state-of-the-art technology and instruments adapted from laparoscopy. These preliminary cases provided an opportunity to modify and adapt these techniques to thoracic procedures. Video thoracoscopy is rapidly evolving in both methods and instrumentation.     

Decellularized dermis in combination with cultivated keratinocytes in a short- and long-term animal experimental investigation

Decellularized human dermis as a potentially ideal scaffold for dermal substitution in severe burns was examined in a two‐staged animal experiment. In an initial step, an in vitro generated composite graft consisting of human keratinocytes and decellularized dermis (AlloDerm®) was transplanted onto nude mice in a short‐term trial (n = 20, 14 days). Subsequently, a combined one‐step grafting of full thickness wounds with both decellularized dermis (in part preincubated with fibroblasts) and cultivated autologous keratinocytes as a cell suspension in fibrin glue was done in a long‐term porcine animal model (n = 10, 6 months). In both series, macroscopic wound healing was evaluated by planimetry. Histological investigations included morphological as well as immunohistochemical parameters. The short‐term study showed both successful integration of the composite grafts and reduction of wound contraction compared with the control group (epithelial grafts). The long‐term porcine study displayed reduced myofibroblast formation and contraction in the wounds that had been treated with fibroblast‐preincubated dermis. After 4 weeks, a decline of the structural integrity of the dermal matrix could be noticed. The utility of decellularized dermis as template for both dermal reconstitution and keratinocyte delivery vehicle was shown. The closure of full thickness wounds by a single‐step combination of an autologous keratinocyte fibrin sealant suspension and acellular dermis in a pig animal model could be shown. Incorporation of fibroblasts led to reduced wound contraction but could not prevent the loss of dermal integrity. The engineered ‘skin’ remained viable and stable over a period of 6 months.     

Anesthetic management for anterior mediastinal mass and mediastinoscopy: a case study

A 27-year-old white male was scheduled for a mediastinoscopy of an anterior mediastinal mass. The patient was induced with thiopental and succinylcholine, in anticipation of possible difficulty managing the airway. There was no distortion of the airway, and he was easily intubated with a No. 8.5 anode tube and given 20 mg of atracurium. The extent of tumor growth was greater than expected and, as a result, biopsies of the neck were taken without the need for mediastinoscopy. The atracurium was reversed with atropine and edrophonium. Although respirations were being assisted, the SaO2 decreased significantly, and end-tidal CO2 was greatly increased. When the drapes were removed, the patient was found to be cyanotic, with vein distention in the neck and upper extremities. All anesthetic agents were discontinued, the patient was hyperventilated with 100% oxygen, 100 mg of lidocaine was given for coughing and breath-holding, and the patient was placed in the reverse Trendelenburg position. The SaO2 then increased, and the end-tidal CO2 decreased. Respirations were spontaneous, and the patient could be extubated. The probable cause of this episode was obstruction of the superior vena cava by the anterior mediastinal mass. When the muscle relaxant was reversed, the increase in intrathoracic pressure caused the mass to compress the superior vena cava. The compression was released by placing the patient in a reverse Trendelenburg position, which caused the mass to shift. In addition to superior vena cava compression, other complications of anterior mediastinal masses include airway obstruction, distortion of anatomy, impaired cerebral circulation and myasthenic syndrome.(ABSTRACT TRUNCATED AT 250 WORDS)