High resolution computed tomography (HRCT) assessment of beta 2-agonist induced bronchodilation in chronic obstructive pulmonary disease patients

The evaluation of airway obstruction reversibility in chronic obstructive pulmonary disease (COPD) patients is currently performed by means of an indirect assessment of drug inducing variations in pulmonary function tests. Imaging techniques, especially high resolution computed tomography (HRCT), usually provide a complete evaluation of lung parenchyma (bronchial and vascular structures), but so far they have never been applied to visualize the effects on the bronchopulmonary tree of some pharmacologic stimuli (beta 2 adrenergic agonist), currently used in clinical practice to disclose the presence of airway reversibility. In order to assess the possible role of HRCT in this setting, five COPD patients have been subjected to a double functional radiologic evaluation before and after salbutamol-induced broncho-dilation, with a rigorous assessment of bronchial diameter changes by means of "bronchus-vessel" ratio, currently used for diagnosing bronchiectasis in COPD patients. The results of this experimental study enable us to visualize drug induced broncho-dilation, with a direct assessment of airway reversibility in these patients, and to show a good correlation between functional and HRCT findings, raising the possibility of evaluation COPD patients with abnormal spirometric results or with early signs of lung involvement.     

垂全催乳素瘤的诊断和治疗指南

3.男性:高催乳素血症通常导致阳痿、不孕和性功能低下.男性患者通常为大腺瘤,有神经系统症状.其原因可能是对症状认识的延误或者肿瘤生物学行为的差异.     

Optimization of the technic in the study of the upper abdomen using magnetic resonance. I. Artifact reduction

Complete motion artifact suppression is possible in abdominal MR imaging with the simple optimization of sequence parameters, with no need for special softwares. The authors have studied the influence of sequence parameters modification on the signal/noise relation and on the presence of motion artifacts. The tested parameters included Repetition Time (TR), 150 to 2000 ms, Echo Time (TE), 20 to 120 ms, and the number of acquisitions, 2 to 16. In T1-weighted sequences, the major advantages were offered by the short TR and short TE association, with many acquisitions. Optimal signal/noise relation and complete motion artifact suppression were thus obtained. In T2-weighted sequences, TE values had to be changed according to the desired contrast enhancement, and the number of acquisitions could not be increased to more than 2 in order to keep the acquisition time short.     

Familial Ehlers-Danlos Syndrome Type II: Abnormal Fibrillogenesis of Dermal Collagen

We examined a father and son affected by Ehlers-Danlos syndrome type II. Both patients had micrognathia together with ligament and skin hyperlaxity. The son exhibited complete cleft palate. Ultrastructural studies revealed abnormal collagen fibrils in the dermis of both patients. In the child the most striking alterations consisted of lateral fusion of an enormous number of collagen fibrils giving rise to huge polymorphic collagen masses. In the father's dermis the great majority of collagen fibrils appeared normal; however, lateral fusion of fibrils together with local abnormal collagen aggregation were occasionally seen. In both patients the dermal elastic network was well developed and elastic fibers appeared normal.     

Speech-controlled generation of radiology reports

Voice entry has been successfully employed to generate radiology reports with a word recognizer with a 1,000-word lexicon capacity. About 50% of reports were able to be dictated with a single 900-word lexicon. This was split into five sections by anatomic or subspecialty application. Each was augmented to 900 words. By switching from one lexicon to another, it was possible to dictate more than 70% of reports. With exclusive use of three lexicons in subspecialty areas (gastrointestinal radiology, neuroradiology, and mammography), and with further modification of the respective vocabulary, it has been possible to employ the system 88% of the time. Twelve percent of cases included wording that was beyond the scope of the lexicon. Computer subsets that allow different translations of some words when used in different contexts have been used. Some of these are used as triggers that will print whole lines, sentences, or even complete reports. Dictation times with voice entry take about 20% longer. Recognition reliability has been greater than 95%.     

Interaction of platelet factor four with cultured vascular endothelial cells

Platelets secrete a low-molecular-weight protein, platelet factor four (PF-4), which binds to and neutralizes heparin and related sulfated glycosaminoglycans (GAGs). To examine the interactions of PF-4 with the GAGs present on endothelial cell surfaces, we incubated 125I-PF-4 with cell suspensions derived from confluent monolayers of cultured bovine aortic endothelium. Binding of 125I-PF-4 was inhibited by a 100-fold excess of nonradioactive PF-4 and varied with duration and temperature of incubation. At 4 degrees C, binding reached equilibrium at 20 minutes with kd = 2.87 mumol/L and Bmax of 63.83 pmol/10(5) cells. Binding capacity was reduced 83.4% by brief incubation of endothelial cells with trypsin and 46.67% by incubation with Flavobacterium heparinase, but was unchanged by chondroitin-ABCase treatment. At 37 degrees C, PF-4 was internalized by confluent monolayer of bovine aortic endothelial cells primarily through low-affinity adsorptive endocytosis. The internalized PF-4 was degraded to amino acids and small peptides with 50% conversion after 18-hour incubation. These studies demonstrate that a secreted platelet protein can bind to and enter endothelial cells. Binding may explain the rapid clearance of released PF-4 from plasma and could have important local effects on endothelial structure and function.     

Immunoblotting characterization of neutrophil antigenic targets in autoimmune neutropenia

We characterized neutrophil autoantigens using an immunoblotting technique with antibodies obtained from patients with autoimmune neutropenia. These results were correlated with serologic characterization of the antibodies, using indirect immunofluorescence and leukoagglutination. Of the 17 sera immunoblotted, 16 showed discrete bands in the molecular weight range of 30 to 112. Three patients with Felty's syndrome reacted with an antigenic target of 80 to 84 Kd molecular mass, a finding not seen in any of the other patients studied. By serologic testing, none of the autoimmune sera showed serologic specificity for any known neutrophil-specific alloantigen. Using an anti-NA-1 serum, we identified antigenic targets at 40, 50, and 101 Kd in both NA-1-positive and NA-1-negative neutrophils. Ten of 17 autoimmune sera showed reactivity in this corresponding range. These studies demonstrate that immunoblotting may be used to identify antigenic targets in autoimmune neutropenia and may suggest a specificity of these antibodies not definable by serologic techniques. Correlation of immunoblot reactivity with disease states associated with immune neutropenia may be useful in the study of the pathogenesis of the different forms of autoimmune neutropenia.     

Delayed hepatic CT scanning: increased confidence and improved detection of hepatic metastases

Fifty oncologic patients with suspected hepatic metastases were prospectively evaluated by dynamic sequential hepatic computed tomography (DSHCT) and by delayed iodine hepatic computed tomography (DICT) scanning. DICT scanning was performed 4-6 hours following administration of 60 g of intravenous iodine. Both techniques were evaluated for lesion definition relative to the adjacent hepatic parenchyma and for numbers of metastases detected. Metastases were detected by both techniques in 26 patients. Fifteen patients (58%) had lesions better defined by DICT. DICT scanning detected more metastases in seven of these 15 patients. In eight patients (31%), there was no difference between the two techniques in numbers of masses detected or lesion definition. In three cases (11%), metastases were more confidently identified on the initial or DSHCT scan. DICT scanning, as described, is useful in defining and detecting hepatic metastases, especially where there is questionable hepatic involvement or better quantification of size is necessary.     

End-tidal carbon dioxide concentration,carbon dioxide production,heart rate,and blood pressure as indicators of induced hyperthermia

In 4 spontaneously breathing, barbiturate-anesthetized dogs, hyperthermia was induced with 2,4-dinitrophenol while rectal temperature, heart rate, mean blood pressure, end-tidal carbon dioxide, and carbon dioxide production (milliliters per minute) were measured continuously. The latter was determined with a pneumotachygraph (to obtain respired volume) and an infrared carbon dioxide analyzer that measured inspired and expired carbon dioxide concentration. Of the five physiologic measurements, the increase in carbon dioxide production preceded the increase in rectal temperature by more than 120 seconds. End-tidal carbon dioxide was an unreliable indicator in the spontaneously breathing animal of approaching hyperthermia during spontaneous breathing due to a transient tachypnea, which decreased end-tidal carbon dioxide. The carbon dioxide production (milliliters per minute) increased immediately and reached three to five times the control value. Blood pressure and heart rate were insensitive indicators of approaching hyperthermia.