Impaired brachial artery flow-mediated dilation and increased carotid intima-media thickness in rheumatoid arthritis patients / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Carotid artery intima-media thickness (CIMT) and brachial artery flow-mediated dilation percentage (FMD%) are common parameters used for detecting subclinical atherosclerosis. This study compared subclinical atherosclerosis of the carotid and brachial arteries in rheumatoid arthritis (RA) patients and healthy controls using high resolution ultrasonography. We also investigated their correlation with clinical factors and the association between FMD% and CIMT.</p><p><b>METHODS</b>One hundred and two RA patients and 46 age-gender matched healthy controls were included in the study. FMD of the brachial artery and CIMT were measured ultrasonographically. Patients with diabetes mellitus, hypertension, renal failure, history of cardiovascular or cerebrovascular disease were excluded. Subjects who were receiving or used high dose steroids were also excluded.</p><p><b>RESULTS</b>The CIMT was significantly higher in patients than that in the control group ((0.697±0.053) vs. (0.554±0.051) mm, P<0.001), whereas brachial artery FMD% was lower in patients than that in the controls ((5.454±2.653)% vs. (8.477±2.851)%, P<0.001). CIMT was related to age, disease duration, tender and swollen joint score, C-reactive protein, systolic blood pressure and high-density lipoprotein. However, FMD% was only association with systolic blood pressure. There was no significant correlation between CIMT and FMD%.</p><p><b>CONCLUSIONS</b>Compared with the healthy control subjects, RA patients without clinically evident cardiovascular disease had subclinical atherosclerosis in terms of impaired FMD% and increased CIMT. FMD% and CIMT may measure a different stage of subclinical atherosclerosis in RA patients.</p>

Solitary pulmonary nodules: comparison of multi-slice computed tomography perfusion study with vascular endothelial growth factor and microvessel density / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The solitary pulmonary nodule (SPN) is one of the most common findings on chest radiographs. The objectives of clinical practice are to differentiate malignant nodules from benign nodules in the least invasive way and to make a specific diagnosis. This study was aimed to evaluate the correlation between perfusion imaging features and microvessel density (MVD) and vascular endothelial growth factors (VEGF) in SPNs using multi-slice computed tomography (MSCT); and to provide the theoretical basis for SPN blood flow pattern and blood flow quantitative features. Also, the study called for the discussion of the method's clinical application value in the differential diagnosis of benign and malignant SPNs.</p><p><b>METHODS</b>Sixty-eight patients with SPN underwent multi-location dynamic contrast enhanced (nonionic contrast material was administrated via the antecubital vein at a rate of 4 ml/s) MSCT. Precontrast and postcontrast attenuations on every scan was studied. Perfusion, peak height, and the ratio of the peak height of the SPN to that of the aorta were analyzed. Perfusion was calculated using the maximum gradient of the time-density curves (TDC) and the peak height of the aorta. The quantitative parameters (perfusion, peak height, ratio of peak height of the SPN to that of the aorta) of the blood flow pattern were compared with MVD and the VEGF expression of immunohistochemistry.</p><p><b>RESULTS</b>The perfusion peak heights of malignant ((96.15 +/- 11.55) HU) and inflammatory ((101.15 +/- 8.41) HU) SPNs were significantly higher than those of benign ((47.24 +/- 9.15) HU) SPNs (P < 0.05, P < 0.05). Ratios of SPN-to-aorta of malignant and inflammatory SPNs were significantly higher than those of benign SPNs (P < 0.05, P < 0.05). No significant differences were found between the peak height and SPN-to-aorta ratio of malignant SPNs and inflammatory SPNs (P > 0.05, P > 0.05). The precontrast densities of inflammatory SPNs were lower than those of malignant SPNs (P < 0.05). Perfusion values of malignant and inflammatory SPNs were significantly higher than those of the benign SPNs (P < 0.05, P < 0.05). The VEGF positive expressions appeared in 32 patients with malignant SPNs and 2 patients with benign SPNs, and the average value of the MVD was higher in patients with malignant SPNs (36.88 +/- 6.76) than in patients with either benign (4.51 +/- 0.60) or inflammatory (26.11 +/- 5.43) SPNs (P < 0.05, P < 0.05). There were statistically significant correlations between the CT perfusion feature and the MVD. The highest correlation was between the peak height of SPN and the MVD (r = 0.657, P < 0.05).</p><p><b>CONCLUSIONS</b>Tumor microvessel density and VEGF expression facilitate the exploration of the pathophysiological basis of CT perfusion in SPNs. Multi-slice CT perfusion has shown strong positive correlations with angiogenesis in SPNs.</p>

Effect of cholesterol lowering on stiffness of aortic and femoral arterial walls in rabbits on a high fat diet / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Researches in arterial elasticity have increased over the past few years. We investigated the effects of simvastatin on vascular stiffness in fat fed rabbits by ultrasonography.</p><p><b>METHODS</b>Thirty rabbits were assigned randomly to 3 groups: normal control group (A), the cholesterol group (B), simvastatin group (C: high fat diet for 4 weeks and high fat diet + simvastatin for further 4 weeks). Stiffness coefficient, pressure strain elastic modulus and velocity of pulse waves in abdominal aorta and femoral artery were measured by ultrasonographic echo tracking at the end of the 4th and the 8th weeks.</p><p><b>RESULTS</b>At the end of the 4th week, stiffness coefficient, pressure strain elastic modulus and pulse wave velocity of femoral artery were significantly increased in group B compared with those in group A. Similarly, at the end of the 8th week, the same parameters of abdominal aorta were significantly increased in group B compared with those in group A. In contrast, stiffness coefficient, pressure strain elastic modulus and pulse wave velocity of femoral artery were significantly decreased in group C compared with those in group B, however, there was no significant difference in parameters of abdominal aorta between groups B and C.</p><p><b>CONCLUSION</b>Short term administration of simvastatin can improve the elasticity of femoral artery but not abdominal aorta.</p>

Edaravone attenuates ischemia-reperfusion injury by inhibiting oxidative stress in a canine lung transplantation model / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Previous reports have confirmed that edaravone has protective effects against ischemia-reperfusion (IR) injury of many organs. In this study, we investigated the effect of edaravone on preventing IR injury of the lung in a canine lung transplantation model.</p><p><b>METHODS</b>Twelve weight-matched pairs of random-bred dogs were randomized into two groups. Within each pair, one dog served as donor and the other as recipient. In the study group, prostaglandin E1(PGE1)(8 microg/kg) was injected into the donor pulmonary artery (PA) before occlusion and the donor lungs were flushed with 1.0 L of LPD solution containing edaravone (10 mg/kg) and stored in the same LPD solution at a temperature of 1 degrees C for 8 hours. The left single lung transplantation was then performed and recipients received intravenous injection with edaravone (10 mg/kg) at the onset of reperfusion. In the control group, edaravone was substituted by the same volume of sterile saline solution. Another six dogs were obtained as normal control group in which left lungs were dissected after thoracotomy without an IR injury. One hour after reperfusion, or after dissection of the left lung, the right lung was excluded from perfusion and ventilation after which, cardiopulmonary parameters were measured. Wet/dry ratios, malondialdehyde (MDA) and myeloperoxidase (MPO) levels were assessed and histological analysis of lung tissue performed at the same time.</p><p><b>RESULTS</b>All animals survived until the end of the experiment. The study group showed significantly decreased wet/dry ratios (treated: (74.1 +/- 4.2)% vs control: (86.8 +/- 5.2)%, P < 0.01), MDA levels (treated: 0.50 +/- 0.08 vs. control: 0.88 +/- 0.15, P < 0.01) and MPO activity (treated: 0.23 +/- 0.05 vs. control: 0.43 +/- 0.07, P < 0.01) compared to the control group two hours after occlusion of the right side. In the control group, pulmonary vascular resistance (PVR) was increased markedly and arterial oxygen partial pressure deteriorated significantly after exclusion of the right side compared to those in the treatment group.</p><p><b>CONCLUSIONS</b>Edaravone attenuates IR-induced lung injury and preserves lung function by inhibiting oxidative stress and decreasing leukocyte extravasation in a canine lung transplantation model.</p>

Bone diseases in rabbits with hyperparathyroidism: computed tomography, magnetic resonance imaging and histopathology / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Hyperparathyroidism (HPT) occurs at an early age and has a high disability rate. Unfortunately, confirmed diagnosis in most patients is done at a very late stage, when the patients have shown typical symptoms and signs, and when treatment does not produce any desirable effect. It has become urgent to find a method that would detect early bone diseases in HPT to obtain time for the ideal treatment. This study evaluated the accuracy of high field magnetic resonance imaging (MRI) combined with spiral computed tomography (SCT) scan in detecting early bone diseases in HPT, through imaging techniques and histopathological examinations on an animal model of HPT.</p><p><b>METHODS</b>Eighty adult rabbits were randomly divided into two groups with forty in each. The control group was fed normal diet (Ca:P = 1:0.7); the experimental group was fed high phosphate diet (Ca:P = 1:7) for 3, 4, 5, or 6-month intervals to establish the animal model of HPT. The staging and imaging findings of the early bone diseases in HPT were determined by high field MRI and SCT scan at the 3rd, 4th, 5th and 6th month. Each rabbit was sacrificed after high field MRI and SCT scan, and the parathyroid and bones were removed for pathological examination to evaluate the accuracy of imaging diagnosis.</p><p><b>RESULTS</b>Parathyroid histopathological studies revealed hyperplasia, osteoporosis and early cortical bone resorption. The bone diseases in HPT displayed different levels of low signal intensity on T(1)WI and low to intermediate signal intensity on T(2)WI in bone of stage 0, I, II or III, but showed correspondingly absent, probable, osteoporotic and subperiosteal cortical resorption on SCT scan.</p><p><b>CONCLUSION</b>High field MRI combined with SCT scan not only detects early bone diseases in HPT, but also indicates staging, and might be a reliable method of studying early bone diseases in HPT.</p>

Effect of hepatic artery embolization on the microwave coagulated area / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To study the effect of hepatic artery embolization on the microwave coagulated area, an in vivo animal experiment.</p><p><b>METHODS</b>Twenty-four suitable hepatic lobes of ten dogs were divided into two groups: microwave coagulation alone 12 lobes (control group) and hepatic artery occlusion with iodized oil and gelatin sponge particles followed by microwave coagulation 12 (experiment group). Microwave coagulation was delivered with an output of 50 W for 300 or 400 seconds with thermal needles introduced parallel to and 5 approximately 20 mm from the puncture needle. After sacrifice of the dogs, their hepatic lobes were sectioned along the puncture line. Then, the appearance and size of the coagulated area were recorded. The tissue specimens were fixed in formalin for light microscopic evaluation.</p><p><b>RESULTS</b>A decline in temperature gradient was detected from the center to the periphery of the affected tissue after the application of microwave coagulation, which was sharper in the control group than in the experimental group. Single polar microwave coagulation at 50 W for 300 seconds produced a necrotic volume of 25 approximately 33 mm in longitudinal diameter and 13 approximately 22 mm in transverse diameter in control group, 33 approximately 44 mm and 24 approximately 32 mm in the experimental group. The coagulation area was slightly bigger when the duration of coagulation was 400 seconds than 300 seconds, without significant difference.</p><p><b>CONCLUSION</b>Hepatic artery occlusion, inhibiting the heat loss caused by hepatic arterial blood flow, is able to significantly enlarge the necrotic volume of microwave coagulation.</p>