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S Graf

Publications and source records attributed to S Graf.

At least 19 recordsLinked to original sources

Ensembl 2007.

The Ensembl (http://www.ensembl.org/) project provides a comprehensive and integrated source of annotation of chordate genome sequences. Over the past year the number of genomes available from Ensembl has increased from 15 to 33, with the addition of sites for the mammalian genomes of elephant, rabbit, armadillo, tenrec, platypus, pig, cat, bush baby, common shrew, microbat and european hedgehog; the fish genomes of stickleback and medaka and the second example of the genomes of the sea squirt (Ciona savignyi) and the mosquito (Aedes aegypti). Some of the major features added during the year include the first complete gene sets for genomes with low-sequence coverage, the introduction of new strain variation data and the introduction of new orthology/paralog annotations based on gene trees.

Animals↗

Myocardial perfusion in patients with typical chest pain and normal angiogram.

BACKGROUND: Approximately 10-30% of patients with typical chest pain present normal epicardial coronaries. In a proportion of these patients, angina is attributed to microvascular dysfunction. Previous studies investigating whether angina is the result of abnormal resting or stress perfusion are controversial but limited by varying inclusion criteria. Therefore, we investigated whether microvascular dysfunction in these patients is associated with perfusion abnormalities at rest or at stress. PATIENTS AND METHODS: In 58 patients (39 female, 19 male, mean age 58+/-10 years) with angina and normal angiogram as well as 10 control patients with atypical chest pain and normal coronaries (six female, four male, mean age 53+/-11 years) myocardial blood flow (MBF) was measured at rest and under dipyridamole using 13N-ammonia PET. Resting MBF and coronary flow reserve (CFR) as the ratio of hyperaemic to resting MBF were corrected for rate-pressure-product (RPP): normalized resting MBF (MBFn)=MBFx10,000/RPP and CFRn=CFRxRPP/10,000. RESULTS: Sixteen/58 patients had a normal CFRn (=2.5; group I; CFRn: 3.1+/-0.88); the same as the controls (CFRn: 3.3+/-0.74). Forty-two/58 patients presented a reduced CFRn (group II; CFRn: 1.78+/-0.57). Group II had both a higher MBFn (group II: 1.30+/-0.33 vs. Group I: 1.03+/-0.26; P<0.05 and vs. controls: 1.07+/-0.19; P<0.01) and a lower hyperaemic MBF (group II: 2.25+/-0.76 mL g-1 min-1 vs. Group I: 3.07+/-0.78 mL g-1 min-1; P<0.001 and vs. controls: 3.41+/-0.94 mL g-1 min-1; P<0.0001). CONCLUSION: Impaired CFRn in patients with typical angina and normal angiogram is owing to both an increased resting and reduced hyperaemic MBF. Therefore, PET represents a prerequisite for further studies to optimize treatment in individuals with anginal pain and normal coronary angiogram.

Adult↗

FDG gamma camera PET equipped with one inch crystal and XCT. Assessment of myocardial viability.

UNLABELLED: Metabolic imaging with 2-[fluorine-18]-fluoro-2-deoxy-D-glucose (FDG) is actually considered as the best method to detect and quantitatively assess myocardial tissue viability. The aim of this study was to investigate the accuracy of FDG gamma camera positron emission tomography (GCPET) imaging equipped with one inch NaI crystals in comparison to FDG dedicated PET (dPET) imaging as a "gold standard" in phantom and clinical studies. PATIENTS, METHODS: Nineteen patients with coronary artery disease (CAD) underwent both imaging modalities. Phantom and clinical GCPET imaging were performed with a dual-headed, coincidence based gamma camera equipped with 1 inch thick NaI crystals and an x-ray tube (XCT) for attenuation correction (AC), as well as with a dedicated PET scanner with AC. (99m)Tc tetrofosmin single-photon emission tomography (SPET) studies were performed for assessment of myocardial perfusion, with AC. RESULTS: Phantom studies showed a significant relation in segmental activity between FDG imaging with AC using GCPET and dPET (r = 0.91, p < 0.001). In clinical studies with AC correlation coefficients of mean segmental FDG uptake and regional defect size were r = 0.87 (p < 0.0001) and r = 0.83 (p < 0.0001), respectively. In regional analysis close agreement was even found in the most attenuated regions of the heart if AC was used in GCPET imaging. The overall agreement for detection of viable myocardium was 81% between FDG-dPET (AC) and FDG-GCPET (AC) and 74% between FDG-dPET (AC) and FDG-GCPET (NC). CONCLUSION: This study suggests that the assessment of myocardial metabolism by means of FDG is feasible with a coincidence based gamma camera equipped with 1 inch thick NaI crystals if AC is performed. The results reveal a close concordance and agreement between FDG-dPET (AC) and FDG-GCPET (AC) as compared to FDG-GCPET (NC).

Aged↗

Attenuation correction for myocardial perfusion imaging. A comparison between SPECT and PET imaging by polar map analysis.

AIM: We investigated the impact of photon attenuation in myocardial perfusion imaging with SPECT and PET in patients with coronary artery disease. In fact, the regional tracer distribution can be quantitatively assessed by polar map analysis if the effects of photon attenuation are accounted for. PET imaging permits accurate measurement of and correction for photon attenuation, whereas results of attenuation correction in SPECT imaging have been inconsistent. PATIENTS, METHODS: We compared photon attenuation in resting perfusion imaging studies with SPECT ((99m)Tc-sestamibi) and PET ((13)N-ammonia) from 21 patients. Transaxial images were reconstructed with and without attenuation correction and reoriented into short axis images. Polar map analysis was utilized to generate regional tracer uptake in six anatomical segments. RESULTS: Average segmental photon attenuation calculated as the ratio of counts in corrected and uncorrected images was 7.2 +/- 1.4 in SPECT and 14.0 +/- 3.1 in PET imaging (p < 0.01). This attenuation factor was significantly related to body mass index for both methods (p < 0.001). While attenuation correction for SPECT imaging did compensate for attenuation effects in the inferior wall (from -15% to +6% vs. PET), relative tracer uptake in the anterior wall in SPECT images was significantly reduced after attenuation correction (from -2% to -18% vs. PET, p < 0.01). CONCLUSION: Differential effects of attenuation correction for myocardial SPECT perfusion imaging need to be considered when algorithms designed to compensate effects of photon attenuation in SPECT imaging are employed in clinical practice.

Aged↗

13N-ammonia rest/stress PET: folic acid improves global coronary vasoreactivity in coronary artery disease patients with normal or elevated homocysteine levels.

AIM: Hyperhomocysteinaemia (Hhcy) is known to be an independent risk factor for vascular disease. Coronary flow reserve (CFR) measured by positron emission tomography (PET) is a sensitive method to monitor the effects of pharmacologic interventions in Hhcy. We assessed coronary vascular reactivity by PET in patients with coronary artery disease (CAD) dependent on their homocysteine (Hcy) levels before and under high dose folic acid supplementation therapy (FAST). PATIENTS, METHODS: Twelve patients with CAD underwent rest/adenosine (13) N-ammonia PET for quantification of myocardial blood flow (MBF) and CFR before and after nine weeks FAST (10 mg/day). RESULTS: Folate levels increased from 21 +/- 6 to 210 +/- 34 microg/l (+900%, p < 0.0001) while Hcy levels decreased from 12.1 +/- 3.6 to 9.1 +/- 3.1 micromol/l ( - 25%; p < 0.01). Global resting MBF remained nearly unchanged after FAST, while stress MBF (from 2.61 +/- 0.93 to 3.25 +/- 1.15 ml/g/min; p = 0.05) and CFR (from 3.00 +/- 0.76 to 3.72 +/- 0.93 ml/g/min; p < 0.05; +24%) significantly increased in patients with normal and elevated Hcy levels (cut off 12 micromol/l). An inverse relation was found between Hcy and CFR (R = - 0.53; p = 0.08) and between Hcy and MBF at rest (R = - 0.62; p < 0.05) at baseline conditions, not persisting after FAST. CONCLUSION: Coronary vascular reactivity can be improved by FAST in patients with CAD and normal or elevated Hcy levels. FAST might lower an increased cardiovascular risk in CAD patients possibly by mechanisms that are not related to Hcy.

Aged↗

[Careers of women in academic surgery].

AIM: The aim of our national survey was to determine personal, working, and career conditions of women in academic surgery in Germany. METHODS: A questionnaire with 47 items was sent to 261 female surgeons working in 36 departments of general, abdominal, trauma, and vascular surgery. A total of 134 (51.3%) from all 36 surgical departments responded with completed surveys. RESULTS: The mean age of the women was 35.1 years (range 27 to 54). Seventy-eight percent of the surgeons worked in departments for general or abdominal surgery, 17% in trauma, and 5% in vascular surgery. 45% of the women had finished residency and 19% were in faculty positions. Eighty percent of those asked were mostly or always content with their working conditions. However, 79% perceived career obstacles in academic surgery. The most frequently addressed obstructions were: predominant male structures (80%), the absence of mentoring programs (70%), too few operative cases per month (67%), and no equality of career opportunities compared to male surgeons (60%). CONCLUSIONS: To reduce career obstructions, which were reported by 79% of the female surgeons, and to encourage those 33% who wanted to leave academic surgery, it seems necessary to improve cooperation between female surgeons, department chairs, and governmental institutions.

Adult↗

Impact on postoperative pain of long-lasting pre-emptive epidural analgesia before total hip replacement: a prospective, randomised, double-blind study.

Clinical studies on pre-emptive analgesia have produced inconsistent results. We conducted a clinical study investigating the effect of long-lasting pre-emptive epidural analgesia on consumption of analgesics and acute pain. Forty-two patients scheduled for elective hip replacement for osteo-arthritis were randomly assigned to receive, on the day before operation, either 5 ml.h(-1) ropivacaine 0.2% (study group, n = 21) or 5 ml.h(-1) saline (control group, n = 21). Postoperative analgesia was achieved in both groups by patient-controlled epidural analgesia (PCEA) with ropivacaine 0.2%. The main outcome measure was consumption of local anaesthetics. Additional parameters included visual analogue pain scale (VAS) scores, consumption of rescue analgesics, requests for PCEA boluses, and side-effects. The pre-operative parameters and pain scores were similar in the two groups. Epidural blocks provided sufficient operative analgesia in all patients. Pre-emptive analgesia was continued for 11-20 h and led to significantly decreased pain scores before surgery. The consumption of local anaesthetics was decreased postoperatively in the study group (194 mg vs. 284 mg in the postoperative period). Furthermore, bolus requests occurred more frequently in the control group. VAS scores did not differ significantly between groups. Long-lasting "pre-emptive" epidural analgesia decreases postoperative pain with improved pain control.

Adult↗

Natriuretic peptides and the prevalence of congestive heart failure in patients with pacemakers.

AIM: The aim of the study was to investigate the diagnostic potential of natriuretic cardiac peptide measurement in the context of left ventricular dysfunction and comorbidities in a pacemaker population. MATERIAL AND METHODS: Ninety-five consecutive patients with pacemakers were included in the study. All patients underwent echocardiography and were asked to complete the Minnesota Living with Heart Failure Questionnaire (MLHFQ). Brain natriuretic peptide (BNP), N-terminal proatrial natriuretic peptide (N-ANP) and atrial natriuretic peptide levels in plasma were measured. RESULTS: Twenty-six percent of patients had reduced systolic left ventricular function; only 16 patients had a history of congestive heart failure. BNP was abnormally elevated in 64%, N-BNP in 72% and N-ANP in 96% of patients. Both BNP (r = 0.30; P < 0.01) and N-ANP (r = 0.39; P < 0.0005) correlated with MLHFQ. The strongest correlation was found between N-ANP and the ejection fraction (r = 0.6; P < 0.0001). Patients were stratified in a high-risk group and a low risk-group according to their N-ANP (N-ANP > 5000 fmol L(-1); n = 63 and N-ANP < 5000 fmol L(-1), n = 32) and BNP levels (BNP > 400 pg mL(-1); n = 17 and BNP < 400 pg mL(-1), n = 78). N-ANP was correlated with hypertension (P < 0.003) and atrial fibrillation (P < 0.03), and BNP with mitral insufficiency (P < 0.002). CONCLUSIONS: Cardiac natriuretic peptides are markedly elevated in the majority of patients with pacemakers. The prognostic significance of BNP and N-ANP in left ventricular dysfunction warrants close follow-up schedules.

Aged↗

Iodine-123-vascular endothelial growth factor-165 (123I-VEGF165). Biodistribution, safety and radiation dosimetry in patients with pancreatic carcinoma.

AIM: Imaging with radiolabelled vascular endothelial growth factor (VEGF) has been developed for the localisation and diagnosis of a variety of human solid tumors including gastrointestinal tumors. METHODS: In this study we investigated the biodistribution, safety and absorbed dose of iodine-123 radiolabelled VEGF(165) ((123)I-VEGF(165)) in 9 patients with pancreatic carcinoma. Following intravenous administration of (123)I-VEGF(165) (189+/-17 MBq; <130 pmole (<5 microg) VEGF(165) per patient), sequential images were recorded during the initial 30 min PI. Serial whole-body images were acquired in anterior and posterior views at various time points. All patients underwent single-photon emission tomography (SPET) imaging. Dosimetry calculations were performed on the basis of gamma camera data. Estimates of radiation absorbed dose were calculated using the MIRDOSE 3 program. RESULTS: The highest absorbed organ doses were found to be thyroid (0.058+/-0.004 mGy/MBq), spleen (0.046+/- 0.017 mGy/MBq), urinary bladder (0.04+/-0.02 mGy/MBq), lungs (0.034+/-0.009 mGy/MBq) and kidneys (0.033+/-0.005 mGy/MBq). The effective dose was estimated to be 0.017+/-0.002 mSv/MBq. A majority of primary pancreatic tumors and their metastases were visualized by (123)I-VEGF(165) scan. CONCLUSION: In vitro binding results confirmed specific binding of (123)I-VEGF(165) to pancreatic tumor cells and tissues. (123)I-VEGF(165) shows favorable dosimetry and is a safe radiopharmaceutical that may be of potential value for the imaging of VEGF receptor status in vivo.

Adenocarcinoma↗

Endogenous nitric oxide synthase inhibitors and renal perfusion in patients with heart failure.

BACKGROUND: Patients with heart failure are characterized by impaired nitric oxide-dependent endothelial vasodilation and, in addition, by reduced renal perfusion. DESIGN: We assessed blood concentrations of the endogenous nitric oxide synthase inhibitor asymmetric dimethylarginine (ADMA) as well as renal haemodynamics to compare normotensive patients with mild heart failure (n = 12, seven males, 70 +/- 1 years, 72.0 +/- 2.7 kg, 92 +/- 2 mmHg, NYHA I/II) and healthy subjects matched with respect to gender, age and body weight (n = 12, seven males, 69 +/- 2 years, 72.7 +/- 2.5 kg, 88 +/- 2 mmHg). RESULTS: Plasma ADMA concentration and renovascular resistance (RVR) were significantly higher (P < 0.01) and effective renal plasma flow (ERPF) significantly lower (P < 0.01) in the patients with heart failure (ADMA 4.18 +/- 0.42 micro mol L-1, RVR 159 +/- 12 mmHg mL-1 min-1, ERPF 381 +/- 26 mL min-1 1.73 m-2) as compared with the healthy controls (ADMA 2.38 +/- 0.11 micro mol L-1, RVR 117 +/- 8 mmHg mL-1 min-1, ERPF 496 +/- 19 mL min-1 1.73 m-2). In contrast, plasma concentrations of l-arginine, homocysteine, symmetric dimethylarginine (i.e. the biologically inactive stereoisomer of ADMA) and plasma renin activity were not significantly different in both groups studied. In the multiple regression analysis, only plasma ADMA concentrations independently predicted reduced ERPF (r = -0.57; P < 0.003). CONCLUSIONS: In normotensive patients with heart failure plasma ADMA concentrations are markedly increased and related to reduced renal perfusion. Thus accumulation of this endogenous nitric oxide inhibitor may play a role in renal pathology in these patients.

Aged↗

Prophylactic anticoagulation with enoxaparin: Is the subcutaneous route appropriate in the critically ill?

BACKGROUND: Subcutaneously administered low-molecular-weight heparins are widely used for prevention of venous thromboembolism. The appropriateness of the subcutaneous route in critically ill patients has never been established. OBJECTIVE: To determine anti-Xa activities in critically ill patients and in noncritically ill patients receiving prophylactic doses of subcutaneous enoxaparin. DESIGN: Prospective, controlled, open-labeled study. SETTING: Tertiary medical-cardiologic-postoperative intensive care unit and a general medical ward at a university hospital. PATIENTS: A total of 16 intensive care unit patients (group 1; age, 61.1 +/- 16 yrs; male/female ratio, 7/9; Acute Physiology and Chronic Health Evaluation II score, 20.9 +/- 7; mechanical ventilation, n = 15; vasopressors, n = 13) and 13 noncritically ill medical patients (group 2; age, 61.7 +/- 9 yrs; male/female ratio, 7/6) were studied. Body mass index (25.7 +/- 5 vs. 24 +/- 6 kg/m2, p = not significant) was comparable and serum creatinine levels (0.83 +/- 0.25 vs. 1.07 +/- 0.3 mg/dL, group 1 vs. 2) were within the normal range in both groups. Patients with impaired renal function, receiving hemofiltration, or requiring therapeutic anticoagulation were not eligible. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Anti-Xa activities were determined at 0, 1, 3, 6, and 12 hrs after a single daily subcutaneous dose of 40 mg enoxaparin on day 1 and at 3 hrs after 40 mg of enoxaparin on days 2-5. Mean anti-Xa levels at 0 to 12 hrs were consistently lower in group 1 compared with group 2 by analysis of variance (p =.001 between groups and over time), as was the area under the curve at 0 to 12 hrs (2.6 +/- 1 vs. 4.2 +/- 1.7 units x mL(-1) x hr(-1), group 1 vs. 2, p =.008). Significant differences in anti-Xa activity were also found on days 2-5 (p =.001). Peak anti-Xa activities at 3 hrs after administration were negatively correlated with the body mass index (r = -.41, p <.03). No correlation was found between the anti-Xa activity at 3 hrs and the dose of norepinephrine (r =.12, p =.7). CONCLUSION: Critically ill patients with normal renal function demonstrated significantly lower anti-Xa levels in response to a single daily dose of subcutaneous enoxaparin when compared with medical patients in the normal ward.

Aged↗

Axial flow catheter pump for circulatory support.

AIM: The development of a percutaneously insertable catheter pump for temporary left ventricular and circulatory support in patients with acute ischemic cardiomyopathy. MATERIAL AND METHODS: The expandable axial flow pump (introduction diameter 9-F, expanded diameter 6.5 mm) is mounted at the tip of a catheter, designed to be placed in aortic transvalvular position. Hydrodynamic tests were performed in a static flow model and in a pulsatile mock circuit (Medos VAD, Stolberg, Germany). Cardiogenic shock was simulating in vitro and in vivo. RESULTS: At a rotation speed of 32,000 rpm the catheter pump delivered a maximum flow of more than 4.0 L/min against a systemic mean pressure of 60 mmHg. Under shock simulation the pump significantly improved output and systemic pressure. CONCLUSION: A percutaneously insertable catheter pump is technically feasible. Hydrodynamic efficacy allows sufficient cardiac support under simulated shock condition.

Animals↗

Clinical aspects of renal transplantation in polycystic kidney disease.

BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) as a systemic disorder represents a special subgroup among patients with end-stage renal disease (ESRD). The different organ manifestations are potential risk factors for cardiovascular events or infections in the course after renal transplantation. Therefore, a long-term evaluation of ADPKD patients and of a control group was done. PATIENTS AND METHODS: 80 ADPKD patients were compared with 88 non-diabetic patients in a retrospective follow-up after renal transplantation. Patient and graft survival (1, 5 and 10 years after transplantation) as well as complications such as infections and cardiovascular events were evaluated. RESULTS: A comparable overall transplant (1 year, 5 years, 10 years: 83%, 73%, 67% ADPKD vs. 84%, 70%, 51% controls) and patient survival rate (1 year, 5 years, 10 years: 96%, 84%, 73% ADPKD vs. 91%, 79%, 58% controls) was found in both groups. Infectious complications with the exception of urinary tract infections (UTIs: ADPKD 42.5% vs. 26%) were diagnosed in similar frequency in the graft recipients. ADPKD patients were significantly more affected by UTIs than their control group (p < 0.05) and tended to suffer more often from lethal infections (ADPKD 7 vs. controls 3), but without statistical significance. Cardiovascular events were not observed to be significantly different between both groups (ADPKD 3 vs. controls 4). An obvious difference was found in patient (p < 0.01) and transplant survival rates (p < 0.05) of male and female ADPKD patients. The female group showed a significantly better outcome. CONCLUSIONS: The overall patient and graft survival rates did not differ between the ADPKD and control groups. The better outcome of female ADPKD graft recipients compared to the male group may be related to a gender-dependent disease severity, possibly due to hormonal effects. As UTIs and lethal septicemia were the leading complications in ADPKD patients, a careful monitoring for infections is important in the post-transplant follow-up.

Adult↗

Homocysteine plasma levels in young patients with coronary artery disease. Relation to history of acute myocardial infarction and anatomical extent of disease.

Although there is considerable epidemiologic evidence for a relationship between plasma homocysteine (Hcy) levels and cardiovascular disease, not all prospective studies have shown such a relationship. Furthermore, data concerning the role of hyperhomocysteinemia in patients with premature coronary artery disease (CAD) are rare. It was the aim of the study to investigate a possible association between Hcy plasma levels in young patients with the extent of CAD and the history of myocardial infarction (MI). A cohort of 94 patients was examined for conventional risk factors and the history of previous transmural MI. Furthermore, coronary angiography was performed to assess the anatomical extent of vessel disease. Plasma Hcy levels were measured by use of a commercial enzyme-linked immunosorbent assay. Only a history of previous MI was significantly associated with hyperhomocysteinemia. There was no relationship between elevated Hcy levels and the anatomical extent of vessel disease in patients with premature CAD. Our data may indicate that hyperhomocysteinemia represents an independent risk factor for acute coronary thrombosis rather than for the development of coronary sclerosis. Thereby, hyperhomocysteinemia may influence the clinical situation after plaque rupture not only by prothrombotic action but also by favouring endothelial dysfunction and vasospasm.

Adult↗

Helicobacter sp. flexispira bacteremia in an immunocompetent young adult.

A young immunocompetent patient was admitted for a febrile illness with malaise, arthralgias, painful leg swelling, and polyserositis. Shortly prior to becoming ill, the patient had traveled to the Northern African desert. The symptoms disappeared during treatment with antibiotics (doxycycline and ceftriaxone) but recurred twice after stopping therapy. A motile gram-negative fusiform rod was isolated from a blood culture taken on the first admission. Analysis of the 16S rRNA gene of the blood culture isolate revealed close similarity with Helicobacter sp. flexispira taxon 8 (99.9% identity), a species that was previously reported as "Flexispira rappini." This is the first reported case of a recurrent Helicobacter sp. flexispira bacteremia in an adult, immunocompetent patient.

Adult↗

Automated assessment of dipyridamole 201Tl myocardial SPECT perfusion scintigraphy by case-based reasoning.

UNLABELLED: This study evaluated the diagnostic accuracy of case-based reasoning (CBR) to automatically detect significant coronary artery disease from dipyridamole 201Tl myocardial SPECT perfusion scintigrams. METHODS: The study population included 240 patients (182 men, 58 women; mean age +/- SD, 61 +/- 12 y) on whom coronary angiography and perfusion scintigraphy were performed within 6 +/- 11 d of each other. The patients were divided into two groups according to the presence or absence of significant coronary disease in any major coronary vessel. Regional myocardial tracer uptake was observed in 84 segments by polar map analysis. For each scintigraphic image, a CBR algorithm based on a similarity metric was used to identify similar scintigraphic images within the case library. The angiographic results of these similar cases were used to obtain the CBR reading, which was compared with the true angiographic results. Myocardial scintigrams were also analyzed by a first-generation Cedars-Sinai (CS) method, including a comparison with a reference database, and by the visual analysis of an expert reader. RESULTS: By receiver-operating-characteristic analysis, the diagnostic accuracy of CBR was not different from the interpretation by the CS algorithm and from visual interpretation (P = not significant [NS]). For detection of significant coronary disease, the respective sensitivities at 50% and 80% specificity were 90% and 67% for CBR, 88% and 65% for CS polar map analysis, and 91% and 74% for visual interpretation. For the detection of coronary disease in the vascular territories assigned to the left anterior descending and the right coronary arteries, CBR and CS polar map analysis showed similar diagnostic accuracy (P = NS). However, for detection of disease in the circumflex artery, CS polar map analysis was slightly better than CBR (P = 0.03). CONCLUSION: Automated interpretation of dipyridamole 201Tl myocardial SPECT perfusion images by CBR has diagnostic accuracy similar to that of visual interpretation or CS analysis. Thus, use of a case library that includes a variety of normal and abnormal perfusion images does not appear to have greater diagnostic power than use of reference limits.

Adult↗

Group A streptococcus clones causing repeated epidemics and endemic disease in intravenous drug users.

Clones of Group A streptococcus (GAS) may spread epidemically and may be associated with enhanced virulence. Sociodemographic and clinical characteristics, together with bacterial isolates, of 79 patients with GAS infection in the Berne region between January 1993 and February 1997 were analysed retrospectively. Using pulsed-field gel electrophoresis, most strains (71%) were found to belong to one of 12 clones. Clonal strains caused significantly more frequent skin abscesses and more severe invasive disease than non-clonal strains. The largest clone (M serotype 1) occurred endemically in non-IVDU patients and caused severe disease in most. Three clones occurred almost exclusively among IVDUs: an M serotype 11 was associated with severe, endemic disease; the other 2 clones, both of M serotype 25, caused epidemics of needle abscesses. Epidemic and endemic spread of GAS clones among IVDUs may be more frequent than previously assumed.

Adolescent↗

Impairment of the plasmin activation system in primary pulmonary hypertension: evidence for gender differences.

Primary pulmonary hypertension (PPH) is a rare disorder, with marked in-situ thrombosis of small pulmonary vessels occurring primarily in adult women. We investigated whether differences in the plasmin- and thrombin activation system are associated with the predominate affection of females. Plasma levels of plasminogen activator inhibitor type 1 (PAI-1), tissue-type plasminogen activator (t-PA), fibrinogen, thrombin-antithrombin (TAT) complexes, and prothrombin fragments (F1.2) were measured at baseline and after standardized venous occlusion (VO) in patients with PPH (24 female, 9 male). At baseline, females showed significant higher TAT levels (p = 0.05), higher t-PA antigen levels (p = 0.01) and higher fibrinogen levels (p = 0.03) with positive correlation to mean pulmonary artery pressure (mPAP), as well as nonsignificant lower t-PA activity, higher PAI-1 antigen and activity and F1.2 levels. After VO, females showed a significantly blunted increase in t-PA antigen (p = 0.01) and t-PA activity (p = 0.001), correlating with mPAP, as well as increased PAI-1 activity (p = 0.05). We hypothesize, that the observed presence of gender differences in the plasmin- and thrombin activation system in PPH leading to an antifibrinolytic/prothrombotic state might, in part, explain the female predominant incidence of this disease.

Adult↗