A defective HIV-1 helper virus DNA, pHyPC, was assembled by deleting the RNA packaging signal, env, nef and the 3'LTR sequences. HIV-1 like virus particles that carry the HIV-1 receptor, CD4 were generated by coexpression of pHyPC and plasmid DNAs encoding different chimeric CD4 proteins. The CD4 particles, sharing the CD4 ectodomain, precisely fused to different membrane anchors. CD4(+) particles specifically bound to HIV-1 Env expressing cells, but any signs of infection into these cells were not detected. Binding was only partially blocked by either polyclonal anti-CD4 antibodies or by high concentrations of soluble CD4. Suprisingly, CD4(+) particles also adsorbed to HeLa, CHO, NIH3T3 and COS-7 cells in the absence of HIV-1 Env expression. Adsorption was comparable in strength and speed to the highly specific CD4-Env interaction. CD4(-) particles exhibited only background levels of binding. Cell binding was CD4- dependent, but it was independent of the cell type from which the CD4(+) particles originated. Interestingly, CD4-dependent/Env-independent binding was only found when CD4 was present on virus particles. This suggests that the micro-environment of CD4 on virus particles uniquely expose this new cell binding activity. Its high affinity could explain in part why infection of Env(+) cells by CD4(+) particles was not detected. Further experiments will be required to evlauate whether this strong membrane interaction could represent one step in the multiple-step viral entry process.
Adsorption ; Animals ; Antibodies ; COS Cells ; DNA ; Helper Viruses ; HIV-1* ; Membranes ; Plasmids ; Product Packaging ; RNA ; Virion

Common iliac artery aneurysm (CIA) often occurs in conjunction with an abdominal aortic aneurysm (AAA), which extends into one or both CIAs in 20% to 30% of patients. Conventional endovascular treatment includes coil embolization of the internal iliac artery (IIA), followed by extension of the main bifurcated AAA stent-graft into the external iliac artery. However, complications from intentional occlusion of unilateral or bilateral IIAs are frequent and sometimes serious. Several methods try to preserve the unilateral or bilateral IIA. Here we report a case of concomitant bilateral CIA and AAA successfully treated with bilateral branched iliac stent-grafts.
Aneurysm ; Aortic Aneurysm, Abdominal ; Endovascular Procedures ; Humans ; Iliac Aneurysm ; Iliac Artery

In order to understand the role of the upstream region of the Mycobacterium leprae 18-kDa gene on the gene regulation, the region was divided into two at the -50 position from the first start codon of the gene and their effect on transcription was examined by using a LacZ transcriptional reporter gene assay. The presence of each of these two regions conferred transcription repression not only on its cognate M. lepraerae 18-kDa gene promoter, but also on a heterologous promoter such as the Mycobacterium bovis BCG hsp65 gene promoter. Moreover, it was found that these regions could confer transcription repression activity in both cases in an orientation-independent manner. Thus, these results indicate that the upstream region of the M. leprae 18-kDa gene harbors transcription repression responsive element(s) acting as an operator and can be further divided into two separately functional regions, suggesting a bipartite structure of the element(s). The identification of transcription repression activity of the upstream region in the M. leprae 18-kDa gene will contribute greatly for the understanding of the 18-kDa gene regulation mechanism, and provide also useful information for the manipulation of mycobacterium gene expression.
Bacterial Proteins/*genetics ; Down-Regulation/*genetics ; *Gene Expression Regulation, Bacterial ; Mycobacterium leprae/*genetics ; Response Elements/*genetics ; Transcription, Genetic

Arterial and cardiac involvement of Behcet's disease is a rare but life threatening complication. The rupture of an arterial aneurysm might result in sudden death. We report a 54-year-old man with an established diagnosis of Behcet's disease who presented with multiple cardiovascular complications that eventually lead to his death. He presented with extensive venous occlusions, and sequentially developed right ventricular thrombosis with multiple pulmonary thromboembolisms, and a pulmonary artery aneurysm. We report this unusual sequence of cardiovascular complications in a patient with Behcet's disease.
Aneurysm, Dissecting/*etiology ; Behcet Syndrome/*complications ; Cardiovascular Diseases/diagnosis/*etiology/ultrasonography ; Fatal Outcome ; Hemoptysis ; Humans ; Male ; Middle Aged ; Pulmonary Artery/*pathology ; Pulmonary Embolism/*etiology ; Risk Factors ; Rupture/etiology ; Tomography, X-Ray Computed

Epidemiology is a discipline characterized by complicated theory and practice.How to make the practice course function better is a topic worthy of exploring in educational reform for clinical students.The article explored the‘Student-Dominated’ Model based on ‘Problem-Based Learning ’ and ‘Team Based Learning ’ in teaching process and compared the model with the traditional one ( Teacher-Dominated Model) .Suggestions were given to further improve effectiveness of epidemiology practice courses.

Among a number of antigens characterized in M. leprae, an etiological agent of Leprosy, the 18 kDa antigen, is unique to M. leprae. We have previously determined a sequence specific element in the 18 kDa gene of M. leprae, which confers transcriptional repression. In this report, we have examined if the element could be applied to genes other than the 18 kDa gene of M. leprae. To identify the roles of the regulatory sequence in heterologous promoter, we have constructed pB3 vector series, which contains BCG hsp65 promoter and the M. leprae 18 kDa transcription repression responsive element in tandem using LacZ gene as a reporter gene. Cloning of hsp65 promoters of M. bovis BCG or M. smegmatis in front of LacZ gene resulted in normal beta- galactosidase activity as expected. However, when the sequence element was placed between the promoter and the LacZ gene, beta-galactosidase activity was reduced 10-fold less. Also we have examined with pB3(-) vector, that harbors the transcription repression responsive element in a reversed orientation, the beta-galactosidase activity was found to be similar to pB3(+) vector. Thus, these results further confirm that M. leprae 18 kDa transcription repression responsive element could regulate BCG hsp65 heterologous promoter and that the element could act as an operator for the transcription of mycobacteria.
beta-Galactosidase ; Clone Cells ; Cloning, Organism ; Galactosidases ; Genes, Reporter ; Lac Operon ; Leprosy ; Mycobacterium bovis* ; Mycobacterium leprae ; Repression, Psychology*

The present study aimed to investigate the protective effect and mechanism of hydrogen sulfide donor NaHS administration against gastric mucosal injury induced by gastric ischemia-reperfusion (GI-R) in rats. GI-R injury was induced by clamping the celiac artery of adult male SD rats for 30 min and followed by reperfusion for 1 h. The rats were randomly divided into sham group, GI-R group, NaHS group, glibenclamide group and pinacidil group. Gastric mucosal damage was analyzed with macroscopic injured area, deep damage was assessed with histopathology scores, and the hydrogen sulfide concentration in plasma was determined by colorimetric method. The results showed that pretreatment of NaHS significantly reduced the injured area and deep damage of the gastric mucosa induced by GI-R. However, NaHS did not significantly alter the levels of hydrogen sulfide in plasma 14 d after NaHS administration. The gastric protective effect of NaHS during reperfusion could be attenuated by glibenclamide, an ATP-sensitive potassium channel (K(ATP)) blocker. However, K(ATP) opener pinacidil inhibited the GI-R-induced injury. These results suggest that exogenous hydrogen sulfide plays a protective role against GI-R injury in rats possibly through modulation of K(ATP) channel opening.
Animals ; Gastric Mucosa ; pathology ; Hydrogen Sulfide ; metabolism ; Ischemic Preconditioning ; methods ; KATP Channels ; metabolism ; physiology ; Male ; Rats ; Rats, Sprague-Dawley ; Reperfusion Injury ; prevention & control ; Stomach ; blood supply ; Sulfides ; pharmacology

The significance of intraoperative electrophysiologic monitoring during microvascular decompression was evaluated prospectively in 261 patients with the hemifacial spasm from 1985 to 1995. The patients were divided into a monitored group and a non-monitored group. Identification of the offending vessels was facilitated by the monitoring during the surgical procedure and the complication rate of the monitored group was significantly lower than that of the non-monitored group (p< 0.05). In addition, the abnormal muscle response continued to improve during the follow-up period, thus the electrophysiological status of the hemifacial spasm after the microvascular decompression improved significantly with time (p< 0.05). In conclusion, intraoperative monitoring is useful for identifying the exact offender among multiple vessels, and lowering the complication rate of the microvascular decompression for the hemifacial spasm.
Adult ; *Decompression, Surgical ; *Facial Muscles ; Female ; Follow-Up Studies ; Human ; Male ; Middle Age ; *Monitoring, Intraoperative ; Spasm/physiopathology/*surgery

The efficacy of hydrocolloid occlusive dressing technique was compared with that of the conventional wet-to-dry gauze dressing technique in decubitus ulcer of stage I and II. Forty-four patients were randomly divided into two treatment groups and each received treatment according to the two different protocols. As a result, 80.8% of the hydrocolloid occlusive dressing group (group 1) and 77.8% of the conventional wet-to-dry gauze dressing group (group 2) healed completely with no statistically significant difference between the two groups. However, the time required for complete healing was shorter in group 1 with 18.9 days compared to 24.3 days in group 2. Ulcer healing speed was also slightly faster in group 1 with 9.1 mm2/day compared to 7.9 mm2/day for group 2. Average treatment time spent by a medical staff member was significantly shorter in group 1 with 20.4 minutes/day compared to 2017 minutes/day in group 2. The hospital cost of the ulcer treatment was higher in group 2 compared to group 1 even without taking into consideration the medical personnel's labor cost. These results indicate that the hydrocolloid occlusive dressing technique offers less time consuming and less expensive method of treatment compared to the conventional technique in stage I andII decubitus ulcers.
Adult ; Aged ; Comparative Study ; Decubitus Ulcer/*therapy ; Female ; Human ; Male ; Middle Age ; *Occlusive Dressings

BACKGROUND/AIMS: Pyloric exclusion has been recommended in patients with severe injury to the pancreas and duodenum. METHODS: A retrospective case review of 8 patients treated with pyloric exclusion following pancreaticoduodenal injury from March 1994 to May 2002 in Department of Surgery, the Catholic University of Korea, Daejeon St. Mary's Hospital. RESULTS: The age range of the patients was from 8 to 31 years. Most of the etiolgy (n=7) was the blunt abdominal trauma and one case due to the iatrogenic injury from the therapeutic endoscopic retrograde cholangiopancretography. The time interval between the injury and the operation varied from 3 to 48 hours. The most common postoperative complication was wound infection (n=8). We found the other complications such as intraabdominal abscess (n=3), pneumonia (n=3), but the complications were treated successfully with conservative measures. There was no mortality cases in these patients. The duration of admission was delayed in the cases of concomitant injury (64 vs 46 days). All patients above 16 years old (n=7) were supported with parenteral nutritional fluid via central intravenous route (mean 32 days). We could not find the spontaneous opening of the pyloric closure at least 4 patients in postoperative 3 months but there was no major complication according to the sustained gastrojejunostomy. CONCLUSION: Pyloric exclusion appears to offer a satisfactory option for the treatment of the severe pancreaticoduodenal injury with minor complication. Do you have any comments about the spontaneous opening of the pyloric closure?
Abscess ; Adolescent ; Duodenum ; Gastric Bypass ; Humans ; Korea ; Mortality ; Pancreas ; Pneumonia ; Postoperative Complications ; Retrospective Studies ; Wound Infection