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H Seifert

Publications and source records attributed to H Seifert.

At least 19 recordsLinked to original sources
PubMed2001

Randomized controlled monocentric comparison of once daily ceftriaxone with tobramycin and cefotaxime three times daily with tobramycin in neutropenic fever.

A prospective, randomized, controlled monocentric trial was performed to evaluate the efficacy and safety of once daily ceftriaxone 2 g plus tobramycin 5 mg/kg in comparison to cefotaxime 2 g t.i.d. plus tobramycin 5 mg/kg qd in the treatment of neutropenic fever. In cases of fever > or = 38.5 degrees C and a neutrophil count below 1000/microliter, patients with hematological malignancies were assigned to ceftriaxone or cefotaxime, each with tobramycin. The primary endpoint was defined as defervescence < 37.5 degrees C on day 4-6 followed by at least 7 afebrile days. Secondary endpoints were overall response, defined as defervescence on day 25 and toxicity. There were 160 episodes of 114 patients included. Fever of unknown origin accounted for 79 episodes (51%), microbiologically defined infection for 36 (23%), clinically defined infection for 27 (17%), and both clinically and microbiologically defined infection for 14 episodes (9%). On an intent-to-treat basis 156 episodes could be evaluated for the primary endpoint. Ceftriaxone plus tobramycin and cefotaxime plus tobramycin resulted in a primary response in 46.9% and 45.3%, respectively. Overall response was achieved on study day 25 in 87.7% and 80%, respectively. No significant difference in toxicity was observed. Once-daily ceftriaxone plus tobramycin was not inferior to cefotaxime t.i.d. plus tobramycin qd in the empirical treatment of neutropenic fever.

Adult↗
PubMed2001

Effects of flue gas composition on the catalytic destruction of chlorinated aromatic compounds with a V-oxide catalyst.

When using catalytic flue gas cleaning, several flue gas compounds may influence oxidation reactions of hazardous volatile organic compounds, possibly leading to lower reaction rates and, thus, to an incomplete destruction. Experimental investigations were performed with regard to the influence of selected flue gas compounds, like hydrogen chloride, sulfur dioxide, oxygen, and water vapour, on the catalytic destruction behavior of chlorobenzenes under flue gas cleaning conditions of an incineration plant. For this purpose, a metal oxide catalyst was operated at different temperatures at a space velocity of 3600 h-1 in a laboratory-scale fixed bed reactor with model flue gases, and with real flue gases generated from the TAMARA waste incineration plant. The results obtained from the studies with model flue gas were analyzed with respect to reaction kinetics. These kinetics were applied for comparison with the experimental data gained in the real flue gas.

Catalysis↗
PubMed2001

Topical application of nitrates onto the papilla of Vater: manometric and clinical results.

BACKGROUND AND STUDY AIMS: Systemic administration of nitrates inhibits motility of the sphincter of Oddi (SO) but is hampered by a decrease of the arterial blood pressure. We evaluate whether topical application of glyceril trinitrate (GTN) onto the papilla can facilitate cannulation of the common bile duct during routine endoscopic retrograde cholangiopancreatography (ERCP) and compare the effect of topical GTN with that of isosorbide dinitrate (ISDN) on SO motility. PATIENTS AND METHODS: A total of 80 patients undergoing routine ERCP for suspected biliary obstruction received topical application of either saline (n = 40) or 10 mg of GTN (n = 40) onto the papilla of Vater in a randomized, double-blind fashion. Thereafter, selective bile-duct cannulation was attempted with a 0.035" hydrophilic guide wire. In another trial, 16 biliary type III patients underwent endoscopic SO-manometry and received in a randomized fashion either 10 mg of GTN (n = 8) or 10 mg of ISDN (n = 8) which was infused topically onto the papilla via the manometric catheter. Thereafter, the manometric recording was continued for a further 5 minutes. RESULTS: A spontaneous opening of the papilla with concurrent transpapillary bile flow was observed in 24/40 patients after topical GTN, and in only 8/40 patients after topical saline (P < 0.01). However, neither the number of cannulation attempts nor the time until successful cannulation differed significantly between the groups. In addition, the pre-cut rate was nearly identical in the two groups. Topical GTN showed no significant influence on the mean arterial blood pressure. The SO-baseline pressure was significantly lowered by topical GTN (28.2+/-12.9 mm Hg before ISDN vs. 22.5+/-13.7 mmHg after P<0.01). The phasic SO motility was also strongly inhibited by both drugs. However, the effect of GTN completely wanes after 3 minutes, whereas ISDN inhibited SO motility for > 5 minutes in all patients. CONCLUSIONS: Both topically administered GTN and ISDN evoked a profound inhibition of SO motility, but the effect of ISDN was longer lasting than that of GTN. However, locally administered GTN did not facilitate selective bile-duct access during routine ERCP.

Administration, Topical↗
PubMed2000

Nosocomial bloodstream infections caused by Acinetobacter species in United States hospitals: clinical features, molecular epidemiology, and antimicrobial susceptibility.

We examined the clinical and epidemiological features of nosocomial bloodstream infections (BSIs) caused by Acinetobacter species and observed from 1 March 1995 through 28 February 1998 at 49 United States hospitals (SCOPE National Surveillance Program). Acinetobacter species were found in 24 hospitals (49%) and accounted for 1.5% of all nosocomial BSIs reported. One hundred twenty-nine isolates were identified either as A. baumannii (n=111) or other Acinetobacter species (n=18). Patients with A. baumannii BSI, compared with patients with nosocomial BSI caused by other gram-negative pathogens, were more frequently observed in the intensive care unit (69% vs. 47%, respectively; P<.001; odds ratio [OR] 2.4; 95% confidence interval [CI] 1.6-3.7) and were more frequently receiving mechanical ventilation (58% vs. 30%, respectively; P<.001; OR 3.2; 95% CI 2.1-4.8). Crude mortality in patients with A. baumannii BSI was 32%. Molecular relatedness of strains was studied by use of polymerase chain reaction-based fingerprinting. Clonal spread of a single strain occurred in 5 hospitals. Interhospital spread of epidemic A. baumannii strains was not observed. The most active antimicrobial agents against A. baumannii (90% minimum inhibitory concentration values) were imipenem (1 mg/L; 100% of isolates susceptible), amikacin (8 mg/L; 96%), tobramycin (4 mg/L; 92%), and doxycycline (4 mg/L; 91%). Thirty percent of isolates were resistant to > or =4 classes of antimicrobials and were considered to be multidrug resistant.

Acinetobacter↗
PubMed2000

Retroperitoneal endoscopic debridement for infected peripancreatic necrosis.

Standard management of infected peripancreatic necrosis consists of open surgical debridement and lavage--a traumatic intervention with substantial morbidity and mortality. As an alternative and novel approach with minimum invasiveness, we present fenestration of the gastric wall and debridement of infected necrosis by direct retroperitoneal endoscopy. In three patients, this strategy led to rapid clinical improvement and no serious complications. Transgastric endoscopic therapy may be a less traumatic alternative to surgery and should be further assessed in prospective studies.

Acute Disease↗
PubMed2000

[Ultrasound diagnosis of penicillin-induced segmental hemorrhagic colitis].

INTRODUCTION: Penicillin-induced segmental haemorrhagic colitis (SHC) is a characteristic and striking but rarely diagnosed clinical entity. Bloody diarrhea and abdominal cramps start a few days after the intake of oral penicillin derivatives. We report the ultrasonographic and clinical findings in nine patients with SHC and compare the results with the findings in ten patients with antibiotic-related pseudomembranous colitis (PMC). METHODS: Nine consecutive patients with SHC (age: 32 +/- 10 years; five males, four females) with PMC-negative proctoscopic findings, stool cultures and negative clostridium difficile toxin and ten patients with PMC (age: 50 +/- 18 years; six males, four females) with positive proctoscopy and Clostridium difficile toxin were clinically evaluated and examined by high resolution ultrasonography. The sonographic findings of the colonic and small bowel walls as well as the clinical course of the diseases were documented. RESULTS: In all nine patients with SHC the wall of the ascending colon was asymmetrically thickened with loss of layer structure. Neither the small bowel nor the cecum were involved in patients with SHC. In all cases a distinct border between involved and uninvolved colon wall was found. During follow-up all patients recovered soon after stopping antibiotic treatment and symptomatic care. In seven of ten patients with PMC pancolitis and in three of ten with left-sided colitis were found at ultrasonography. In all patients with PMC the bowel wall was symmetrically thickened with the layers remaining distinct. DISCUSSION: The knowledge of the clinical characteristics and sonographic findings of penicillin-induced segmental haemorrhagic colitis may reduce the need for invasive endoscopic and radiological investigations in diagnosis and follow-up. The age of patients, clinical course and sonographic findings may be helpful in differentiating patients with SHC and PMC.

Adolescent↗
PubMed2000

Sedation with propofol plus midazolam versus propofol alone for interventional endoscopic procedures: a prospective, randomized study.

AIM: Adequate patient sedation is mandatory for most interventional endoscopic procedures. Recent anaesthesiologic studies indicates that propofol and midazolam act synergistically in combination and therefore may be superior to sedation with propofol alone in terms of sedation efficacy, recovery and costs (due to a presumed lower total dose of propofol needed). METHODS: A total of 239 consecutive patients undergoing therapeutic EGD or ERCP (EGD/ERCP-ratio, 1:1) randomly received either propofol alone (n=120, group A, loading dose 40-60 mg intravenously, followed by repeated doses of 20 mg) or propofol plus midazolam (n=119, group B, initial midazolam dose of 2. 5-3.5 mg intravenously, followed by repeated doses of 20 mg of propofol) for sedation. Vital signs (heart rate, blood pressure, oxygen saturation, electrocardiogram) were continuously monitored. Procedure-related parameters, the recovery time and quality (post-anaesthesia recovery score) as well as the patient's co-operation and tolerance to the procedure (visual analogue scale) were prospectively assessed. RESULTS: Patients of group A and B were well matched with respect to demographic and clinical data, endoscopic findings, and the type of associated procedures. In group A, a mean dose of 0.25 +/- 0.13 mg.min/kg propofol was used compared to 0.20 +/- 0.09 mg.min/kg of propofol in group B (P < 0.01, plus additional 2.9 +/- 0.5 mg of midazolam). Clinically relevant changes in vital signs were observed at comparable frequencies with a lowering of the systolic blood pressure < 90 mmHg in six out of 119 patients in group B and one out of 120 patients in group A (P=0.07). The sedation efficacy was rated similarly in both groups, whereas the mean recovery time (group A, 19 +/- 7 min vs. group B, 25 +/- 8 min, P < 0.05) as well as the recovery score (post-anaesthesia recovery score group A, 8.0 +/- 1.1 vs. post-anaesthesia recovery score group B, 7.3 +/- 1.2, P < 0.001) were significantly better with propofol alone than with propofol plus midazolam. CONCLUSION: During therapeutic endoscopy, sedation with propofol and midazolam requires a lower total dose of propofol, but otherwise has no superior sedation efficacy and is associated with a slower post-procedure recovery than sedation with propofol alone.

Adult↗
PubMed2000

Endoscopic injection of botulinum toxin in patients with recurrent acute pancreatitis due to pancreatic sphincter of Oddi dysfunction.

AIM: To evaluate the technical feasibility, safety, and short-term efficacy of botulinum toxin injection for pancreatic sphincter of Oddi dysfunction and to analyse whether the symptomatic response to botulinum toxin might be a predictor of outcome for endoscopic sphincterotomy. METHODS: Fifteen consecutive patients (nine female, aged 38 +/- 12 years) with frequent attacks (median four) of acute pancreatitis within 6 months, and manometrically proven pancreatic sphincter of Oddi dysfunction underwent endoscopic injection of 100 units of botulinum toxin into the major papilla. All patients underwent prospective follow-up thereafter and in cases of recurrent pancreatitis manometry this was repeated and pancreatic sphincterotomy was performed. RESULTS: No side-effects occurred after botulinum toxin injection in any patient. Within 3 months after botulinum toxin treatment, 12 out of 15 patients remained asymptomatic (80% primary response). Only one out of three patients without symptomatic benefit showed continued elevated pancreatic sphincter pressure at manometry and only this patient benefited from pancreatic sphincterotomy later on. Eleven of the 12 patients initially responding to botulinum toxin injection developed a symptomatic relapse 6 +/- 2 months after botulinum toxin treatment. These patients then achieved long-term clinical remission from pancreatic or combined (biliary and pancreatic, n=5) sphincterotomy (median follow-up, 15 months). CONCLUSION: Endoscopic botulinum toxin injection into the papilla of Vater is a safe procedure for treatment of pancreatic sphincter of Oddi dysfunction that may provide short-term relief in about 80% of the patients. Those patients who respond to botulinum toxin may subsequently gain definitive cure from sphincterotomy.

Acute Disease↗
PubMed2000

Manometrically-guided endoscopic injection of botulinum toxin for esophageal achalasia: a pilot trial.

AIMS: Some patients gained only short-term response (< 6 months) after botulinum toxin (BTX) injection for achalasia. This may be due to an incorrect site of injection when targeting the lower esophageal sphincter by using endoscopic landmarks only. PATIENTS AND METHODS: 7 elderly patients (4 females, 67 +/- 20 years) with classical achalasia received manometrically-guided botulinum toxin injection by means of a double-channel endoscope. Thereafter, they were clinically re-evaluated at 6 weeks and later on at bi-monthly intervals. RESULTS: The mean symptom score decreased 6 weeks after the manometrically-guided BTX-treatment from 12 +/- 2 (before BTX) to 6 +/- 2 points (p = 0.02). However, according to the study criteria one patient did not respond to BTX-injection and underwent subsequent cardiomyotomy. The LES-resting pressure was found not to be altered in this patient (6 weeks after BTX-injection) but manometry revealed a marked decrease of the LES-tone in 3 other patients who benefitted from BTX-injection. 5 of the 6 patients, who initially benefited from BTX-injection, relapsed 10 months (range, 6-13 months) after their initial BTX-treatment. They all were treated with repeated BTX-injections. At completion of the study (1.5-year follow-up) the mean symptom score of the 6 patients was still significantly lower (6 +/- 2 points) than before study entry (p = 0.03). CONCLUSION: Manometrically-guided endoscopic BTX-injection is a simple, safe and highly effective (during 1.5-year follow-up) technique for treatment of esophageal achalasia. With the manometrically-guided injection technique one may obtain a longer lasting symptomatic response than with the traditional method of BTX-application.

Adult↗
PubMed2000

[Local injection of depot corticosteroids in endoscopic therapy of benign bile duct strictures].

BACKGROUND: Local injection of depot-corticosteroids into benign esophageal strictures has been proven to maintain the effects of bougienage or balloon dilation. METHODS: Eight consecutive patients with benign common bile duct (CBD)-strictures (postoperative, n = 6, primary-sclerosing cholangitis, n = 2) were enrolled in this pilot trial. All had undergone initial balloon dilation and insertion of a 10F-plastic prostheses without relevant effects on the stricture diameter four to six weeks before. Than all patients underwent another balloon dilation and insertion of a 10F-Tannenbaum-stent. In the same session injection of 2 x 10 mg of triamcinolone (Volon A, Bristol-Myers Squibb, München) into the CBD-wall at the stricture site by means of a sclerotherapy needle was performed. Four to six weeks later ERC was repeated and balloon dilation and/or stent exchange was performed whenever indicated. RESULTS: The initial mean diameter of the CBD-stenoses was 1.81 +/- 0.65 mm. The mean serum levels of the alkaline phosphatase (AP) and of bilirubin were 455 +/- 188 U/L and 4.9 +/- 2.2 mg/dl, respectively. After the initial balloon dilation and stent insertion no significant improvement had been registered (1.9 +/- 0.7 mm). However, after local triamcinolone injection and the second dilation/stent insertion the diameter of the CBD-stenosis increased significantly to 3.68 +/- 0.96 mm (p < 0.01). No adverse affects were recognized. Three patients had complete recovery of their CBD-stenosis after a third dilation, the remaining five patients were cured after two or three additional balloon dilations with intermittent stent exchange. Thereafter, no recurrence of a CBD-stenosis was observed during a median follow-up of twelve months. At completion of the study the mean serum AP- and bilirubin level were 195 +/- 87 U/L and 1.2 +/- 0.4 mg/dl, respectively. CONCLUSION: Local application of depot corticosteroids is a feasible and safe procedure for therapy of benign CBD-stenoses. The results of this pilot trial justify a randomized study.

Adult↗
PubMed2000

Endoscopic sphincter of Oddi manometry with a portable electronic microtransducer system: comparison with the perfusion manometry method and routine clinical application.

BACKGROUND AND STUDY AIMS: Endoscopic perfusion manometry (PM) of the sphincter of Oddi (SO) requires expensive equipment which is relatively large and uncomfortable to handle in the endoscopic retrograde cholangiopancreatography (ERCP) setting. Furthermore, the volume load of the biliopancreatic system may contribute to the increased risk of pancreatitis after SO manometry. PATIENTS AND METHODS: The newly developed small and lightweight microtransducer system consists of a portable data-logger with integrated online display which is connected to a 4-Fr manometry probe. The manometry catheter is inserted endoscopically into the biliopancreatic system via a 7-Fr Teflon sheath. SO motility can be observed online on the display but the data can also be stored for later analysis on a personal computer (PC). To validate the new method, 15 patients with suspected biliary SO dysfunction underwent both PM as well as microtransducer manometry (MTM) in randomized order. Thereafter, 50 consecutive patients with suspected biliary or pancreatic SO dysfunction were investigated solely by MTM. RESULTS: PM was possible in 13 of 15 cases whereas MTM could be performed in all 15 patients. The basal SO pressure tended to be lower (approximately 5 mmHg) when measured with the MTM, compared with the PM method, but there was a significant and nearly linear correlation between the basal SO pressures obtained by both methods (r=0.98, P<0.001). SO dysfunction was diagnosed in the same five patients using both methods. Furthermore, the parameters of phasic SO motility were highly comparable when measured by MTM and PM. MTM was carried out successfully in 49 of 50 patients and only one MTM probe was used for all examinations, without malfunction. The endoscopist was able to diagnose SO dysfunction (by immediate observation of SO motility on the display) in 19 of 20 patients (when compared with the later PC analysis) and SO motility was judged correctly as normal in the remaining 29 cases. MTM was repeated in five patients with SOD 1-6 weeks after the first examination and the manometric findings were confirmed in all cases. Mild postmanometry pancreatitis was observed in only one of 49 patients (2%). CONCLUSIONS: Endoscopic MTM is a reliable, safe, very easy to handle, and low-cost alternative for the clinical assessment of SO motility.

Adult↗
PubMed2000

[Reduction of the radiation exposure of patients caused by selected interventional and angiographic procedures].

PURPOSE: To reduce patient doses caused by selected interventional and angiographic procedures using the digital C-arm unit "Multiskop". MATERIALS AND METHODS: After a patient study done previously, physical measurements with test phantoms were carried out, and physical-technical parameters such as distance between focus and image intensifier, additional filtration, and radiation dose per image were optimised. Then, the dose-area product (DAP) and the fluoroscopic time were measured for 130 percutaneous transluminal angioplasties (PTA), 40 PTA with stent implantation, 61 embolisations, and 302 digital subtraction angiographies (DSA). In the case of 16 PTA, 9 embolisations, and 38 DSA the number of radiographs was determined, and the DAP was divided into two parts, fluoroscopy and radiography. The measuring values were compared with data of the patient study done previously. RESULTS: The median values of the DAP and the fluoroscopic time amounted to 25 Gy cm2 and 9.7 min for PTA, 97 Gy cm2 and 8.5 min for PTA with stent implantation, 88 Gy cm2 and 17.2 min for embolisation as well as 54 Gy cm2 and 2.8 min for DSA. For the relation between DAP caused by fluoroscopy and radiography, and the number of radiographs, median values of 0.76 and 63 for PTA, 0.81 and 123 for embolisation as well as 1.85 and 134 for DSA were determined. In comparison to the patient study done previously the median values of the DAP were reduced by 31% for PTA, 26% for PTA with stent implantation, 55% for embolisation, and 38% for DSA. CONCLUSIONS: The comparison between the patient studies done previously and recently indicates the great potential of dose reduction for interventional and angiographic procedures. Although the X-ray equipment is ten years old the patient dose can be reduced by organizational and physical-technical modifications to such an extent that preliminary national reference dose values will not be exceeded. For further significant dose reductions while maintaining adequate image quality it will be necessary to purchase a modern X-ray equipment with pulsed fluoroscopy and automatic filter selection.

Angiography↗
PubMed2000

Endoscopic ultrasound-guided one-step transmural drainage of cystic abdominal lesions with a large-channel echo endoscope.

BACKGROUND AND STUDY AIMS: Transmual endoscopic drainage of peripancreatic fluid collections under endoscopic ultrasound (EUS) control has been reported. We evaluated a facilitated technique of one-step puncture and drainage using a new stenting device and a large-channel echo endoscope. PATIENTS AND METHODS: EUS-guided transumural drainage of cystic lesions was attempted in six male patients. The drainage sites were duodenal in two instances and gastric in four. The lesions were pseudocysts, arising from chronic pancreatitis (n=2), and following acute pancreatitis (n=3), and one abscess. The median size of the pseudocysts was 50mm (range, 25 to 90). The punctures were carried out under direct EUS guidance, using a new echo endoscope with a 3.2-mm working channel. Transmural drainage was done using modified 7-F stents. Stents were inserted directly over a 1-mm puncture needle and their position was optimized using a 7-F pusher connected to the stent by a special construction. The stents were released by withdrawing the needle. RESULTS: EUS-guided one-step drainage was technically successful in all 6 patients. It was possible to position the stents as desired, regardless of the location, size or pathogenesis of the target lesions. There were no complications associated with the endoscopic interventions. All the lesions, including two with putrid contents, had collapsed by the day following drainage. The stents were removed after a median period of 2 weeks (range 2-12). The cysts had completely resolved in four patients at follow-ups of 3-13 months (range). The patient with the gastric abscess underwent gastrectomy 2 weeks after stent extraction, because of a coincidental adenocarcinoma at the cardia, the abscess being resolved. One patient with necrotizing pancreatitis, who refused surgical treatment, died because of septic complications. CONCLUSIONS: New large-channel echo endoscopes allow more aggressive endoscopic interventions to be carried out safely under direct EUS control. One-step drainage using the new 7-F stent-over-needle device was effective for six cystic lesions of variable origin.

Adult↗
PubMed2000

Comparative activities of ciprofloxacin, clinafloxacin, gatifloxacin, gemifloxacin, levofloxacin, moxifloxacin, and trovafloxacin against epidemiologically defined Acinetobacter baumannii strains.

In vitro activities of seven fluoroquinolones against 140 clinical Acinetobacter baumannii isolates representing 138 different strain types were determined. The rank order of activity was clinafloxacin > gatifloxacin > levofloxacin > trovafloxacin > gemifloxacin = moxifloxacin > ciprofloxacin. The 31 outbreak-related A. baumannii strains were significantly more resistant than were 109 sporadic strains.

Acinetobacter↗
PubMed2000

Antibody response to lipopolysaccharide in patients colonized or infected with an endemic strain of Acinetobacter genomic species 13 sensu Tjernberg and Ursing.

The levels of antilipopolysaccharide (anti-LPS) antibodies in patients colonized with an endemic Acinetobacter strain were compared to those in patients with bloodstream infections. Seropositivity and seronegativity correlated with positive and negative blood cultures, respectively, indicating that determination of the level of anti-LPS antibodies is useful for diagnosing Acinetobacter infections.

Acinetobacter↗
PubMed2000

[Radiation exposure to patients caused by single-photon transmission measurement in PET].

AIM: The aim of the study was the determination of the radiation exposure to the patient caused by single-photon transmission measurement for 3D whole-body PET. MATERIAL AND METHOD: Single-photon-transmission measurement is performed using two Cs-137 point-sources (E gamma = 662 keV, A = 2*614 MBq) on a 3D PET scanner (ECAT ART). During a simulation of a whole body transmission scan (axial length: 75 cm, 6 contigous bed positions) dose measurements with thermoluminescent dosimeters were carried out using a thorax and an abdomen phantom. Following the guidelines of the ICRU report No. 60 an estimation of the effective dose caused by a single-photon transmission measurement was calculated. RESULTS: For a total acquisition time of 360 min (6 beds with an acquisition time of 60 min per bed) the absorbed doses amounted to: surface (xyphoid) 189 microGy, heart 196 microGy, lungs 234 microGy, vertebra 240 microGy, liver 204 microGy, gonads 205 microGy, thyroid 249 microGy and bladder 185 microGy resulting in a conversion factor of 1.7*10(-4) mSv/(h*MBq). The estimation of the effective dose for a patient's transmission (acquisition time of 3.2 min per bed) yields a value of 11 microSv. An estimation of the ratio of the conversion factors for transmission measurements in single-photon- and in coincidence mode (two Ge-68/Ga-68 rod sources of 40 MBq each), respectively, resulted in a value of 0.18. The comparison of the effective doses caused by single-photon transmission and by emission measurement (injection of 250 MBq of FDG) yields a ratio of 2.3*10(-3). CONCLUSION: The radiation exposure of the patient caused by the transmission measurement for 3D whole-body-PET can be neglected. In comparison with the coincidence-transmission using uncollimated line sources of low activity the radiation exposure is still reduced using single photon trans-mission with collimated point sources of high activity.

Computer Simulation↗
PubMed2000

Angiotensin-converting enzyme gene insertion/deletion polymorphism and carotid artery wall thickness in patients with peripheral arterial occlusive disease.

BACKGROUND: It has been suggested that the deletion polymorphism of the angiotensin converting enzyme (ACE) gene is linked to a high risk of cardiovascular disease. The relationship between the insertion/deletion (I/D) polymorphism of the ACE gene and the carotid intima-media thickness in patients with peripheral arterial occlusive disease is unknown. We tested the hypothesis that the early progression of atherosclerosis in the extracranial carotid arteries in patients with peripheral arterial disease is associated with a genetic predisposition. METHODS: This prospective trial included 98 patients who only had manifestations of arteriosclerotic disease in peripheral arterial vascular regions of the lower extremities (stable stage II PAOD). Maximal common carotid intima-media thickness (mIMT) was measured using high resolution B-mode ultrasonography. Determinations of ACE gene polymorphism were made using a polymerase chain reaction technique. Multivariate regression analysis was performed to assess the influence of ACE genotypes, ACE activity and vascular risk factors on intima-media thickness. RESULTS: There was no significant association between intima-media thickness and ACE gene polymorphism. History of symptomatic peripheral arterial disease without local or systemic progression exists in subjects with the II-genotype significantly longer than in subjects with the DD genotype (p=0.01). With the presence of an II-genotype, there was also a tendency towards a thinner intima-media thickness. We found significant correlations between intima-media thickness and age (p<0.0001), fasting serum insulin (p=0.001), and lipoprotein (a) (p=0.008). CONCLUSIONS: In the present study involving patients with stage II peripheral arterial occlusive disease, ACE gene polymorphism could not be identified as a determining marker for the development of intima-media thickening in the common carotid artery. However, it can be assumed that there is a reduced risk for the systemic progression of atherosclerosis in patients with the II genotype.

Arterial Occlusive Diseases↗