The influence of sex hormones on ocular blood flow in women

PURPOSE: To investigate the influence of sex hormones on ocular haemodynamics, blood flow velocities in the ophthalmic and central retinal arteries and serum levels of sex hormones were measured in pre- and postmenopausal women. METHODS: Colour Doppler imaging (CDI) was used to determine the flow velocities (peak systolic velocity [PSV] and end-diastolic velocity [EDV]) and the resistive index (RI) in the ophthalmic and central retinal arteries in 22 premenopausal and 32 postmenopausal women, who had never received hormone replacement therapy. Serum levels were measured for oestradiol, free testosterone and follicle-stimulating hormone. The CDI parameters were compared between the two groups and the influence of serum levels of oestradiol and testosterone on blood flow velocities and the resistive indices were analysed. RESULTS: After correcting for age and mean arterial blood pressure, an analysis of covariance disclosed a significantly lower EDV (p=0.02) and a significantly higher RI (p=0.01) in the central retinal artery of postmenopausal women compared with premenopausal women. Partial correlation analysis, controlling for age, revealed significant correlations between the CDI parameters and serum levels of oestradiol and testosterone. For premenopausal women, PSV (r=0.58, p=0.04) and EDV (r=0.73, p=0.006) in the ophthalmic artery correlated positively with serum oestradiol levels. The RI in the central retinal artery decreased with increasing oestradiol levels in both groups (premenopausal r= -0.40, p=0.04; postmenopausal r= -0.32, p=0.05). Peak systolic velocity in the central retinal artery correlated negatively (r= -0.49, p=0.04), whereas the RI correlated positively (r=0.53, p=0.02) with testosterone levels in the premenopausal group. Postmenopausal women with higher testosterone levels had lower EDV (r= -0.53, p=0.007) in the central retinal artery and higher RI in both vessels (ophthalmic artery r=0.48, p=0.01; central retinal artery r=0.61, p=0.002). CONCLUSION: Our data provide evidence of a relationship between serum sex hormone levels and blood flow velocities and resistive indices in retrobulbar arteries. Oestradiol appears to have beneficial effects on ocular haemodynamics, whereas testosterone may act as an antagonistic to the effects of oestrogen.     

Dose-related effects of theophylline added to modified Euro-Collins solution used for hypothermic preservation of lung

OBJECTIVE: To investigate the dose-related effects of theophylline in prevention of ischemia-reperfusion injury of the lung. DESIGN: Experimental study. SETTINGS: University hospital. PARTICIPANTS: Thirty Wistar rats. INTERVENTIONS: In experimental group 1 (G-I) (n = 5) 20 mg/L, in G-II (n = 5) 100 mg/L, in G-III (n = 5) 400 mg/L, and in G-IV (n = 5) 1000 mg/L of theophylline was added to modified Euro-Collins solution and perfused the lungs. Lungs were extracted without an ischemic period in control group 1 (C-I) and perfused with modified Euro-Collins solution in control group 2 (C-II). Lungs were kept in a hypothermic state for 6 hours and then ventilated for 30 minutes with 100% O(2). MEASUREMENTS AND MAIN RESULTS: Tissue levels of dien congugate (DC) and malonylaldehyde (MDA) were measured. Comparison of 6 groups revealed statistically significant differences for DC and MDA (p < 0.0001 for both comparisons). Both DC and MDA levels of C-II were found to be higher than G-III and G-IV (p = 0.008). DC and MDA levels of G-III and G-IV were significantly lower than G-I and G-II (p = 0.008 for all comparisons). CONCLUSION: The results of this study showed that 400 mg/L and 1000 mg/L of theophylline added to the modified Euro-Collins solution decreased the intermediate products of lipid peroxidation. Theophylline merits further investigation in ischemia-reperfusion studies as a potentially beneficial agent.     

Invasive staging of superior mediastinum in non-small cell lung cancer patients with specific indications

This prospective study was done between February 2001 and December 2002 on 84 non-small cell lung cancer patients who were apparently operable. We selectively performed mediastinoscopy to 46 patients (54.76%, group 1) with the following indications: clinical T4 tumor, high operative risk, radiologically enlarged mediastinal lymph nodes, clinical T3 tumors with central location, radiologically identified mediastinal lymph nodes of any size with adeno or large cell carcinoma histology. Other 38 patients (45.23%, group 2) underwent thoracotomy without mediastinoscopy. Sensitivity, specificity, negative predictive value and positive predictive value of the indications were calculated. Cost analysis was done in the 84 patients and the results were compared with alternative mediastinal staging strategies (vs. routine, and vs. selectively to patients with radiologically positive mediastinal lymph nodes) if they had been applied to our population. Group 1 had higher selectivity to differentiate N2 patients (p=0.02). Sensitivity, specificity, negative predictive value and positive predictive value of indications were calculated as: 0.85, 0.54, 0.92 and 0.36, respectively. Our approach was most economical in terms of total cost per patient and money spent unnecessarily per patient. Mediastinal evaluation in operable lung cancer patients should decrease the number of surgical procedures, N2 disease found at thoracotomy and cost.     

Non-traumatic colorectal perforations.

Over a 6 year period, between January 1992 and December 1997, 30 patients with non-traumatic colorectal perforations undergoing laparotomy were reviewed. The aim of this study was to evaluate predictions on the prognosis using the Mannheim Peritonitis Index (MPI) and to evaluate the risk of this complication. The mean age of the patients was 56.4 years (range 16-88 years). The male:female ratio was 19:11. All patients showed signs of peritonitis and underwent emergency operations. In 50% (15) of the patients, tumor was the cause. According to the MPI scoring, there were 18 patients with an MPI score of 26 or less and 12 patients with an MPI score of 27 or more. For patients with a score less than 27 the mortality rate was zero (0/18) and for score greater than 26, 66.6% (8/12). Overall mortality was 26.6% (8/30). Of 15 patients with perforated colorectal cancers, four patients died (26.6%). The mortality rate for benign perforations was 26.6% (4/15) also. In conclusion, colorectal cancers are the most common cause of the non-traumatic colorectal perforations. Patients with an MPI score greater than 26 represent the highest risk group.     

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.     

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.