Visualization of palisade veins in esophageal varices by endoscopic color Doppler ultrasonography

Background: Endoscopic color Doppler ultrasonography (ECDUS) is a useful modality for obtaining color flow images of esophageal varices. Levovist is a microbubble echo‐enhancing agent that improves Doppler ultrasound examination. This study is designed to evaluate the usefulness of ECDUS using Levovist in diagnosing palisade veins of esophageal varices. Methods: The study involved 67 patients with esophageal varices using ECDUS. All 67 patients received Levovist intravenously at a concentration of 300 mg/mL. A 7.5‐mL dose of the contrast agent was injected at a slow infusion rate of 1 mL/min. We compared vessel images detected with precontrast with those detected by enhanced ECDUS. Results: Color flow images of palisade veins were obtained in 16 (23.9%) of the 67 patients with precontrast ECDUS. Vessel images of palisade veins were detected in 15 of 61 F2 type varices (24.6%) and in one of six F3 varices (16.7%). The color flows of these vessels showed a continuous wave on fast‐Fourier transform analysis. Sixteen palisade veins had velocities in the 3.3 cm/s?11.6 cm/s range. Color flow images of palisade veins were obtained in 27 (40.3%) of the 67 cases by enhanced ECDUS using Levovist. Palisade veins could be delineated after Levovist contrast in 11 patients who could not be detected on precontrast ECDUS. After Levovist contrast, color flow images detected with precontrast ECDUS were enhanced in all patients. Conclusion: Endoscopic color Doppler ultrasonography with Levovist contrast can improve the diagnostic quality of the palisade veins in esophageal varices.     

Prostate-specific antigen adjusted for the transition zone volume as a second screening test: A prospective study of 248 cases

AIM: This study was conducted to verify the effectiveness of prostate-specific antigen adjusted for the transition zone volume (PSATZ), and its availability as a second screening test for prostate cancer detection. MATERIALS AND METHODS: Total prostate-specific antigen (PSA) and free PSA was measured in male patients who visited our outpatient department for voiding difficulty or screening for prostate cancer. Patients who had an intermediate PSA level between 4.0 and 10.0 ng/mL, with an apparently normal prostate on a digital rectal examination, were enrolled. PSATZ, free-to-total PSA ratio (F/T ratio) and PSA density (PSAD) were calculated and statistical comparisons between biopsy-positive (cancer) and biopsy-negative patients (benign) were conducted. RESULTS: Of 248 patients, 51 (20.6%) had prostate cancer and 197 (79.4%) had benign prostatic hyperplasia (BPH) on pathologic examination. Mean PSA, PSAD, F/T ratio and PSATZ were 7.48 +/- 1.77 ng/mL, 0.23 +/- 0.09 ng/mL per mL, 0.14 +/- 0.08 and 0.71 +/- 0.44 ng/mL per mL in patients with prostate cancer and 6.59 +/- 1.60 ng/mL, 0.16 +/- 0.07 ng/mL per mL, 0.21 +/- 0.11 and 0.36 +/- 0.30 ng/mL per mL in patients with benign, respectively. Receiver operating characteristics (ROC) curve analysis demonstrated that PSATZ predicted the biopsy outcome better than F/T ratio. With a cut-off value of 0.37 ng/mL per mL, PSATZ had a sensitivity of 74.5% and a specificity of 72.6% for predicting prostate cancer. The maximal cut-off value that preserves 100% of sensitivity was 0.2, and at this cut-off value, 16.1% of unnecessary biopsies could be reduced. CONCLUSIONS: Prostate-specific antigen adjusted for the transition zone volume may be more useful than other strategies in detecting prostate cancer in patients with intermediate PSA levels of 4.0-10.0 ng/mL. It can be used as a second screening test to reduce unnecessary biopsy.     

Effect of Intraatrial Reentry on Initiation of Atrioventricular Reentrant Tachycardia

We studied the effect of intratrial reentry (IAE) on initiation of orthodromic reentrant tachycardia (ORT) in 150 patients with Wolff-Parkinson-White syndrome using His-bundle recording and the atrial extrastimulus technique. IAR was initiated by premature atrial stimulation in 44 patients (29%), and it was followed by ORT in 16 patients (11%). In 8 patients (5%), IAR promoted the initiation of ORT, whereas in 5 patients (3%), IAR inhibited the initiation of ORT. These findings suggest that ORT is frequently induced following IAR. IAR, which was frequently observed during electrophysiological studies, seems to play an important role in the initiation of ORT.     

电离辐射致股骨头坏死早期病理特点和机制的研究

Objective To observe the earlier pathological character and mechanism of radiation osteonecrosis in femoral head, in order to provide evidences for the earlier diagnosis and prevention of radiation osteonecrosis of femoral head. Methods Single femoral head of rats were irradiated singly with 30 Gy of 137 Cs γ-ray. The rats were executed after 2, 6 and 12 weeks, then the femurs were stained with HE and histopatholngical changes were observed by light microscope. The bone marrow mesenchymal stem cells (BMSCs) were cultured after 2 weeks and its proliferation and the colony formation were observed. The rats were endo-perfused with microfili contrast medium 12 weeks later, and the 3-dimensional structure of capillaries by Micro-CT was re-estabhshed to detect the pathological changes of capillaries after irradiation. Result The irradiated femur showed deranged cbondrocyte, decreased osteocyte, shrinking nucleus, increased empty bone lacuna and reduced bone trabocnla (P < 0.05). Micro-CT showed the discontinued small vessels and absence(6.65 %) capillaries in irradiated femur were obviously less than those of the unirradiated (12.3 %)(P < 0.001). The proliferation of BMSCs was slowed, the number of colony in irradiated group (10 %) was less than that of control (21 %) (P < 0.001). Conclusions The preliminary histopathological changes of osteoradionecrosis on femoral head could be increased the empty bone lacuna, and the bone lacuna above 30 % was the sign of the earlier period of osteoradionecrosis. The osteonecrosis of femoral head induced by radiation is not only correlated to the damages to the bone, but also to the damages to BMSCs and capillaries.     

Chronic Treatment with Prazosin Causes a Subtype-specific Increase in the α1-Adrenoceptor Density of the Stressed Rat Cerebral Cortex

The effects of chronic treatment with prazosin and of immobilization stress on the α₁-adrenoceptor subtypes in rat cerebral cortex have been examined. Prazosin-treated rats were allowed free access to tap water containing two different concentrations of prazosin (16 or 156 mg L^?) for 5 weeks. The mean plasma concentrations of prazosin were 5 ng mL^? in groups treated with a low dose and 8 or 14 ng mL^? in those treated with a high dose. Immobilization stress (2 h day^?, 2 weeks) or chronic treatment with a low dose of prazosin caused no significant change in the affinity for [³H]prazosin or in the maximum number of α₁-adrenoceptor sites (B_max). However, treatment with prazosin (low dose) combined with stress increased the density of α₁-adrenoceptors with low affinity for prazosin. Treatment with a high dose of prazosin increased the density of α_1L-adrenoceptors, irrespective of stress loading. The densities of α_1A- and α_1B-adrenoceptors with high affinity for prazosin were increased only after treatment with a high dose of prazosin in combination with stress. These results indicate that three distinct α₁-adrenoceptor subtypes, α_1A, α_1B and α_1L, might be affected differently by treatment with prazosin and by stress.     

Role of ureteroscopic biopsy in the management of upper urinary tract malignancy

BACKGROUND: The aim of the study presented here was to examine the accuracy of ureteroscopic biopsy in the diagnosis of upper urinary tract transitional cell carcinoma (TCC) and whether nephron-sparing management (holmium YAG laser, transurethral resection or partial ureterectomy) is possible or not based on pathological diagnosis. METHODS: Forty consecutive patients underwent ureteroscopic biopsy with the use of 3-Fr cold cup forceps. Pathological diagnosis of the biopsy sample and grade or stage of surgically resected tumors were compared. In patients with grade 1 or 2 TCC diagnosed by ureteroscopic biopsy, the disease-free and survival rates determined whether nephron-sparing management was performed or not. RESULTS: There were no major complications associated with ureteroscopic biopsy. The pathological grading of the biopsy specimen was almost the same as that of the surgically resected specimen. Eighty five percent of grade 2 or 3 TCC showed muscle invasive disease. There were no significant differences in the disease-free and survival rates between the nephroureterectomy and the nephron-sparing management groups, except for grade 3 or pT3 tumors. CONCLUSION: Ureteroscopic biopsy is safe and accurate if sufficient tissue sample is obtained. Ureteroscopic biopsy should be performed in patients who require nephron-sparing management. Nephroureterectomy can be avoided if the tumor is confirmed as low-grade.