Search PubMed⌕ Search

Biomedical subjects

M Reiter

Publications and source records attributed to M Reiter.

At least 19 recordsLinked to original sources
PubMed2007

Plaque imaging of the internal carotid artery - correlation of B-flow imaging with histopathology.

BACKGROUND AND PURPOSE: The noninvasive identification of plaque types prone to cause symptomatic disease is of great interest to improve the effectiveness of surgical or interventional management. The purpose of the present prospective pilot study was to evaluate the association between the results of imaging-the novel sonography technique B-flow imaging (BFI), B-mode, and color Doppler imaging (CDI)-and histopathologic examination in the characterization of internal carotid artery (ICA) plaques. METHODS: Twenty-eight consecutive patients with high-grade internal carotid artery stenosis scheduled for carotid endarterectomy were included. BFI, B-mode, and CDI images were used to classify the plaques applying the standardized scores of Beletsky et al and the American Heart Association (AHA), to calculate the gray-scale median (GSM) and to detect potential ulcerations; histopathologic examination results of explanted plaques served as the "gold standard." RESULTS: Based on the classification of Beletsky et al, BFI and histopathologic examination results agreed in 21 (75%, kappa = 0.61, P < .001) patients, and the corresponding results for B-mode were 19 (68%, kappa = 0.52, P < .001) patients, respectively. Corresponding results for the AHA classification revealed inferior agreements for BFI (19 patients/68%, kappa = 0.38, P = .003) and B-mode (17 patients/61%, kappa = 0.25, P = .045). The median GSM for BFI and B-mode correlated significantly (r = 0.95, P < .001). The sensitivity of BFI for the detection of ulcerated plaques was 100% and the specificity was 95.8%; corresponding values for CDI were 100% and 92.7%, respectively. CONCLUSION: BFI and the combination of B-mode and CDI exhibit comparable results in the assessment of ICA plaque components and plaque ulceration as well as in the determination of GSM levels.

Aged↗
PubMed2006

Evaluation of inspiratory muscle function in a healthy austrian population--practical aspects.

BACKGROUND: There is no clear evidence whether inspiratory muscle strength (Pi(max)) is closely linked to inspiratory muscle endurance (T(lim)). Moreover, normal values of T(lim), measured by flow-resistive loads, have not been established. OBJECTIVES: We tried to find answers to the following questions: Is it possible to establish normative values of T(lim) when using flow-dependent, resistive loads? Are Pi(max) and Borg scale values predictors of T(lim)? Are anthropometric and spirometric data closely related to T(lim)? Is it really necessary to measure T(lim) in addition to Pi(max) when evaluating inspiratory muscle function? METHODS: Sixty-eight healthy Austrian volunteers between 17 and 75 years of age and with a sedentary lifestyle participated in our study. Pi(max) was defined as the maximal inspiratory mouth pressure, measured with a differential pressure transducer. T(lim) was determined as the time span until exhaustion, while breathing against a resistive loading device. RESULTS: Pi(max) values showed a low intra- and high interindividual variability for both sexes and were significantly age, weight and height dependent. For male subjects, Pi(max) was also significantly related to spirometric parameters. T(lim) values showed a very high interindividual variability, but a low intraindividual variability. Interestingly, no correlation was found between T(lim) and Pi(max), nor lung function parameters and age. CONCLUSIONS: The results indicate that both Pi(max) and T(lim) have to be determined when inspiratory muscle function is measured. Normal values for T(lim), evaluated by flow-resistive loads, cannot be satisfactorily established due to the high interindividual variability.

Adolescent↗
PubMed2006

Influence of HMG-CoA-reductase inhibitors on the body fat status.

BACKGROUND: While the literature has conclusively shown a significant decrease of plasma lipids after intake of HMG-CoA reductase inhibitors, there is no detailed information provided about their effects on the body fat status. PATIENTS AND METHODS: We performed a retrospective analysis of a prospective randomized controlled trial including consecutive patients with suspected arterial occlusive disease. Normolipidemic patients served as the control group and hyperlipidemic patients were randomized to either 20 mg atorvastatin or to 40 mg simvastatin. At baseline, after 6 weeks and after 6 months we assessed the relative body fat, the waist circumference and the body mass index (BMI) as well as plasma total cholesterol (chol), low-densitiy lipoprotein cholesterol (LDL) and triglycerides (TG). RESULTS: In total we included 129 patients in our analysis. The body fat status remained unchanged in the control group as well as in the atorvastatin group (all p > 0.05) for the whole study period, while simvastatin treatment led to a slight, but significant increase of the relative body fat (+ 4.2%) between the 6 weeks and 6 months assessment (p = 0.013). CONCLUSIONS: Long-term intake of statins seems to have no positive influence on parameters of the body fat status and therefore misses one important goal in the cardiovascular risk prevention.

Adipose Tissue↗
PubMed2006

Skin cholesterol: test performance, evaluation of potential determinants and correlation analysis with cardiovascular risk factors and circulating markers of inflammation.

BACKGROUND: Skin cholesterol (SkC) has been suggested to be an additional risk predictor, so we evaluated the test performance, potential determinants of this marker as well as a potential correlation of SkC with markers of inflammation and the history of cardiovascular events. PATIENTS AND METHODS: SkC, determined by the non-invasive PREVU POC Skin Sterol test, as well as serum lipids, the body fat status, high-sensitive CRP (hs-CRP) and serum amyloid A (SAA) were evaluated in consecutive patients with and without documented atherosclerotic disease. RESULTS: SkC was assessed in 201 patients. The within-day precision (CV) was 3.8%, the day-to-day CV of the right hand was 8.6% and 4.3% for the left hand, respectively. Neither univariate analysis nor multiple regressions identified a significant influence of age, sex, serum lipids, body fat status, smoking or diabetes mellitus on SkC, corresponding results were observed in a further analysis including 174 of these patients concerning hs-CRP and SAA (all p > 0.05). T-test analyses detected no significant differences between patients with and without a history of coronary, peripheral vascular and cerebrovascular events (all p > 0.05). CONCLUSIONS: The PREVU POC Skin Sterol test for the assessment of SkC proved an acceptable test performance. SkC is independent from serum lipids, traditional cardiovascular risk factors, two sensitive markers of systemic inflammation as well as the history of cardiovascular events indicating that the perception of this parameter as an established marker of vascular disease is premature.

Aged↗
PubMed2004

Prostanoids for intermittent claudication.

BACKGROUND: Peripheral arterial occlusive disease (PAOD) is a common cause of morbidity in the general population. While numerous studies have established the efficacy of prostanoids in PAOD stages III and IV the question of the role of prostanoids as an alternative or additive treatment in patients suffering from claudicatio intermittens (PAOD II) has not yet been clearly answered. OBJECTIVES: The aim of this review was to evaluate effects of prostanoids in patients with intermittent claudication. SEARCH STRATEGY: Computerised searches of the Cochrane Peripheral Vascular Diseases Specialised Register (last searched April 2003), The Cochrane Central Register of Controlled Trials (CENTRAL) (last searched Issue 1, 2003), MEDLINE and EMBASE were undertaken. In addition relevant journals were hand-searched. SELECTION CRITERIA: Randomized clinical trials describing the effects of prostanoids in the treatment of patients suffering from intermittent claudication have been considered for inclusion. DATA COLLECTION AND ANALYSIS: All reviewers assessed the quality of studies and extracted data unblinded. Statistical analysis including tests for heterogeneity and overall effect were performed by using MetaView of Review Manager 4.2. All numeric values are expressed as mean +/- Standard deviation (SD). MAIN RESULTS: Eighteen studies were included for analysis. A significant heterogeneity between the included studies was detected in most of the subgroup analysis. Five studies compared the effects of prostaglandin E1 (PGE1) versus placebo, and reported in their individual results significant increases in walking distances after the administration of PGE1. The attained increase in walking distances appears to be not merely a short-term effect because several studies reported that walking capacity remained increased even after termination of treatment. On the other hand, oral or intravenous prostacyclin did not increase the walking distances significantly. At least one adverse reaction was reported from 23.6% of the patients treated with prostacyclin (PGI2), and its analogues and from 13.7% of the patients treated with PGE1. REVIEWER'S CONCLUSIONS: Because of the heterogeneity between most of the included studies, we did not pool relevant parts of the data by meta-analysis. Based on the individual results of the published literature, patients with intermittent claudication seem to benefit from administration (intravenous or intra-arterial) of PGE1 by a significant improvement of their walking capacity. Further well-conducted randomized, double blinded trials, with a sufficient number of patients to provide statistical powerful information, should be performed to confirm the results of this review.

Alprostadil↗
PubMed2004

[Extended field-of-view sonography in Achilles tendon disease: a comparison with MR imaging].

PURPOSE: To evaluate the role of real-time extended field-of-view sonography (EFOVS) in symptomatic Achilles tendon disease in comparison with MR imaging (MRI). MATERIALS AND METHODS: Twenty-three symptomatic tendons were examined by conventional grayscale sonography, EFOVS and MRI, which served as the gold standard. RESULTS: The median tendon thickness in MRI was 7.8 mm (IQR 3.1) and correlated significantly to the results of EFOVS (7.0 mm, IQR 2; r = 0.74, P < 0.01). In total, MRI detected 24 lesions in 18 tendons and EFOVS 21 hypoechoic lesions in 15 tendons, corresponding to a sensitivity of 87.5 % and specificity of 100 %. The additional usage of conventional grayscale sonography improved sensitivity to 95.8 %. The median distance of the largest lesion to the calcaneal tuberosity was 10.4 mm (IQR 3.4) in MRI and 8.5 mm (IQR 5.1) in EFOVS (r = 0.64; P < 0.05). The sensitivity and specificity of EFOVS for the detection of a peritendinitis were 63.6 % and 66.7 %, respectively. Corresponding values for the detection of a bursitis were 68.8 % and 28.6 %. The additional usage of conventional grayscale sonography improved the specificity to 85.7 %. CONCLUSION: The combination of EFOVS and grayscale sonography has the potential to challenge MRI as the preferred imaging method in diagnosing symptomatic Achilles tendon disease, especially with respect to saving time and cost and the absence of any contraindications.

Achilles Tendon↗
PubMed2004

[Three-dimensional digital rotation angiography for embolization therapy of uterine leiomyomas: first results].

PURPOSE: To evaluate three-dimensional rotational digital subtraction angiography (3D-RDSA) in the embolization of the uterine artery in the treatment of symptomatic uterine leiomyomas (fibroids). MATERIALS AND METHODS: Eight women with complex pelvic vessel anatomy caused by large fibroids were embolized using 3D-RDSA. The raw data were sent to an external workstation, and video files with a resolution of one image/3 degrees and a scan range of 180 degrees in a surface-shaded display mode were produced. The primary goal was to assess an image intensifier angulation for the optimal visualization of the origin of the uterine artery. In addition, the intervention parameters were compared with those of 48 patients with standard angiography. RESULTS: The analysis revealed no single angulation that can be recommended for standard angiography. No statistical differences were found between both groups concerning fluoroscopy time, dosage area product and amount of administered contrast medium (p > 0.05). CONCLUSION: It can be stated that 3D-RDSA is a feasible method that facilitates the catheterization of the uterine artery even in patients with complex pelvic vessel anatomy, with the potential to reduce the radiation exposure and the amount of administered contrast medium in future embolization therapy of symptomatic uterine fibroids.

Angiography↗
PubMed2004

Colour and power Doppler sonography in symptomatic Achilles tendon disease.

The present trial focused on the exact role of colour and power Doppler sonography in Achilles tendinopathy and correlated these techniques with the clinical severity of the disease and with findings on grey-scale sonography. Twenty patients with in total 28 symptomatic Achilles tendons were included in this prospective trial. Additionally included were the asymptomatic tendons (n = 12) of patients and both tendons (n = 30) of fifteen controls. The pain score of Robinson - which ranges from 0 (strong severe pain) to 100 (asymptomatic) - was used to assess clinical severity of the disease. Both tendons of patients and controls were examined by a GE LOGIQ 9 trade mark scanner with a small-parts 14 MHz transducer. Grey-scale sonography detected in total 31 focal hypoechoic areas in 19 (68 %) of the 28 symptomatic tendons. Colour as well as power Doppler sonography detected blood flow in 14 (74 %) of the 19 tendons with focal hypoechoic areas. No blood flow was detected in the remaining symptomatic tendons (n = 14) and in the asymptomatic tendons of patients or in both tendons of controls. Colour and power Doppler sonography resulted in a specificity of 100 % and a sensitivity of 50 % for symptomatic Achilles tendinopathy. Patients with blood flow within the tendon had a significantly lower score according to Robinson than symptomatic patients without flow (P = 0.009). It is concluded that colour and/or power Doppler sonography are useful as an adjunct to grey-scale sonography in the examination of Achilles tendinosis, especially because the presence of blood flow is associated with stronger pain, discomfort and physical restriction.

Achilles Tendon↗
PubMed2002

Prostanoids in the treatment of intermittent claudication--a meta-analysis.

BACKGROUND: Numerous studies have established the efficacy of prostanoids in PAD stages III and IV, but the role of prostanoids as an alternative or additive treatment in patients suffering from PAD II is less clear. To resolve this uncertainty we performed a meta-analysis of all randomised controlled studies analysing effects of prostanoids in patients suffering from intermittent claudication. METHODS: 96 studies have been screened by computerised searches of MEDLINE and EMBASE. Relevant studies were pooled in Cochrane's Review-manager 4.1. RESULTS: 19 studies were included for further analysis. Five studies could not be pooled for analysing walking distances, because standard deviations were not stated. Eight studies compared effects of any prostanoid i.v. vs. placebo. In total 557 patients (281/276) were included for analysis of painfree--walking distance (PFWD) and 519 patients (262/257) for analysis of maximum walking distance (MWD). Prostanoids compared to placebo significantly improved mean PFWD by 28% (7%-49%, P = 0.008) and mean MWD by 30% (11%-50%, P = 0.002). At least one adverse reaction was reported from 39.6% of the patients treated with prostacyclin and its analogues and from 13.7% of the patients treated with prostaglandin E1. CONCLUSION: Patients suffering from intermittent claudication benefit from administration of prostaglandin E1 by a significant improvement of their walking capacity.

Arterial Occlusive Diseases↗
PubMed2002

[The role of chest X-rays in the diagnosis of thoracic aortic aneurysms].

OBJECTIVE: To evaluate the role of routine chest radiographs in the diagnosis of thoracic aortic aneurysms (TAA). METHODS: An electronic full-text search was performed in our radiological information system for all patients who underwent chest radiograph under standard conditions between 1998 and 2000 and who had suspected widening or aneurysm of the thoracic aorta as a diagnosis. Computed tomography (CT) of the thorax was used as the gold standard and had to be performed within a period of 30 days. Two independent and blinded observers evaluated different morphologic and morphometric parameters in the diagnosis and correlated the results with those of CT. RESULTS: 28 patients were included in the present trial. With almost perfect interobserver correlation (r = 0.95) both investigated morphometric parameters correlated well (r = 0.85 and 0.83) with the diameter of the aorta as evaluated with CT. While a low subjective over-all probability for TAA had a negative predictive value of 100 %, we found that, despite an almost perfect interobserver variability (Kappa > 0.8), none of the investigated morphologic parameters (discrepancy between the ascending and descending aorta, displacement of the trachea to the right and caudal displacement of the left main bronchus) was significantly correlated with the final diagnosis. CONCLUSION: The investigated morphometric parameters help to estimate the diameter of the aorta in the arch and in the descending section, but none of the morphologic criteria can be used for the diagnosis of TAA.

Aortic Aneurysm, Thoracic↗
PubMed2002

Scanning probe microscopy for Bio & Nanotechnology onboard the ISS.

Since February 2002 Kayser-Threde GmbH, Munich (Germany) leads a study under ESA contract in order to study the technical feasibility and the applications of "Scanning Probe Microscopy for Bio & Nanotechnology onboard the ISS (SONOS)". The objective of this effort is to demonstrate the feasibility of an SPM instrument on the ISS. An appropriate breadboard model will be manufactured and tested within the present study. Its development will be based upon the developed pocket size SPM instrument by Professor W. Hecki of the Center for Crystallography and NanoScience (CeNS) at the Ludwig-Maximilians University (LMU) in Munich. Scanning probe microscopy (SPM) investigates surface structures at very high resolution and can perform nanoengineering. These techniques can be applied to non organic as well as to organic or biological materials.

Journal Article↗
PubMed2001

Results of a new rapid d-dimer assay (cardiac d-dimer) in the diagnosis of deep vein thrombosis.

The objective was to evaluate the accuracy of a new full blood rapid D-dimer assay in the diagnosis of suspected deep vein thrombosis (DVT). In 100 consecutive patients with suspected DVT, clinical probability was staged according to a pretest score proposed by Wells. For the determination of plasma D-dimer, heparin and citrate blood samples were drawn, and Cardiac D-dimer, STA-LIA, and Tina-quant tests were performed. Final diagnosis was confirmed either by duplex sonography or ascending venography. DVT was diagnosed in 37%, thrombophlebitis in 10%, and no venous thromboembolism was diagnosed in 52%. In 2% pulmonary embolism was detected and one patient was dismissed before final diagnosis. Cardiac D-dimer assay from citrate tubes showed a sensitivity of 88.6%, a specificity of 54%, a positive predictive value of 57.4%, and a negative predictive value of 87.1%. Nearly identical results were observed with heparin tubes. Corresponding results were 88.6%, 48%, 52.5%, and 85.7% for STA-LIA and 88.6%, 46%, 53.4%, and 85.2% for Tina-quant, respectively. In conclusion, we can say that Cardiac D-dimer is a rapid, whole blood assay with a great potential for clinical use. It can help in diagnosing DVT from citrate as well as heparin tubes with comparable sensitivity, specificity, positive and negative predictive values as STA-LIA and Tina-quant tests.

Adult↗
PubMed2001

Minor constituents of Spigelia anthelmia and their cardiac activities.

A more detailed phytochemical analysis of extracts of the aerial parts of Spigelia anthelmia L. (Loganiaceae) yielded 20 structurally related new compounds besides spiganthine and ryanodine. Structure elucidation was achieved mainly by spectroscopic methods. The compounds were tested on their cardiac and on their insect antifeedant activities.

Animals↗
PubMed2001

Long-term results of systemic thrombolysis therapy in aorto-iliac occlusive disease.

BACKGROUND: Long term results of systemic lysis therapy with ultrahigh-dose urokinase (UHUK) in reopening aorto-iliac occlusive disease have not yet been evaluated. This prospective trial investigates the long-term primary patency rate, the rate of complications and assesses the role of different expected influence parameters on the primary patency rate. PATIENTS AND METHODS: 72 patients with aorto-iliac occlusive disease received daily intravenous infusions of UHUK either until reperfusion or--after at least 3 cycles--no progress in recanalization could be stated on two consecutive days by duplex scanning. RESULTS: Systemic lysis therapy was morphological at least partially successful in 44 patients (61.1%). Concomitant percutaneous transluminal angioplasty was performed in 41 patients (56.9%), surgery in 7 patients (9.7%) and both in further 5 patients (6.9%). In patients without surgery hemodynamical success could be achieved in 39 patients (54.2%) and even more important clinical success in 51 patients (70.8%). Compared to baseline results patients improved significantly in ankle/brachial pressure index and in Fontaine stages (p < 0.001), the same results could be seen after a mean follow-up period of 62 months. Thrombolysis was complicated in 4 patients (5.6%) by macroembolizations but no major bleedings or deaths occurred. Primary patency was 76%, 64%, and 43% after 1, 5 and 10 years. Male sex and distal localization were significantly correlated with lower primary clinical patency. CONCLUSION: Systemic lysis therapy is an alternative to surgical intervention in acute and subacute aorto-iliac occlusive disease, because it offers acceptable long-term results with a low rate of complications.

Adult↗
PubMed2001

[Development of a novel influenza vaccine derived from a continuous cell line].

Influenza viruses for production are presently produced in embryonated hen"s eggs. This conventional standard methodology is extremely cumbersome; it requires millions of eggs and an extensive purification to reduce the amount of contaminating egg proteins and to minimise the risk of allergies against egg albumin. The shortage of eggs in a pandemic situation, the selection of egg-adapted variants and the presence of adventitious viruses has emphasised the necessity for production of Influenza vaccines on a well characterised stable cell line. Our established serum and protein free Vero cell technology has been successfully adapted to large scale production of a huge variety of Influenza virus strains. The production in 1200 liter fermenter cultures under serum free conditions gave antigen yields comparable to the conventional embryonated egg technology. The development of a rapid and efficient purification scheme resulted in a safe high purity vaccine which was at least as immunogenic as conventional egg-derived vaccines in a mouse model. Clinical trials in the UK, Poland and Austria demonstrated that the Vero cell derived influenza vaccine is well tolerated, safe and highly immunogenic in humans.

Animals↗
PubMed2000

Effects of inhibition of calcium and potassium currents in guinea-pig cardiac contraction: comparison of beta-caryophyllene oxide, eugenol, and nifedipine.

1. To investigate the effects of the clove oil constituents beta-caryophyllene oxide and eugenol on the heart muscle, experiments were performed on isolated papillary muscles and on ventricular myocytes of the guinea-pig. The results were compared with those obtained with the dihydropyridine, nifedipine. 2. All three substances exerted negative inotropic effects in heart muscle although with different potencies and different influences on the time course of the contraction curve. 3. They all reduced rested-state contractions (RSCs) in the presence of isoprenaline which are thought to be due to the Ca(2+) current (I(Ca)). 4. beta-Caryophyllene oxide, eugenol and nifedipine inhibited the I(Ca) in single cells from the guinea-pig ventricle in a concentration-dependent, reversible way, but with different potencies. 5. In addition to the I(Ca)-inhibiting effect, beta-caryophyllene oxide strongly inhibited and eugenol slightly inhibited the potassium current. 6. The action potential of papillary muscles at a 1 Hz contraction frequency was greatly shortened by nifedipine, slightly shortened by eugenol, but not changed by beta-caryophyllene oxide. 7. The inhibition of the potassium current by beta-caryophyllene oxide obviously prevents a shortening of the action potential due to the diminution of the I(Ca). Accordingly, the negative inotropic effect of beta-caryophyllene oxide is closely related to the inhibition of I(Ca). In contrast, eugenol and nifedipine, which shorten the action potential, exert stronger negative inotropic effects than expected from their influence on I(Ca). 8. The results show that the negative inotropic effect of a calcium channel blocker can be attenuated by an additional inhibition of potassium channels.

Action Potentials↗
PubMed1999

A novel mammalian cell (Vero) derived influenza virus vaccine: development, characterization and industrial scale production.

Influenza virus for vaccine production are presently produced in embryonated chicken eggs. This conventional standard methodology is extremely cumbersome; it requires a huge amount of eggs and an extensive purification to reduce the amount of contaminating egg proteins and to minimize the risk of allergies against egg albumin. The shortage of eggs in a pandemic situation, the selection of egg-adapted variants and the presence of adventitious viruses has emphasized the necessity for production of influenza vaccines on a well characterized stable cell line. Our established Vero cell technology has been successfully adapted to large scale production of a variety of influenza virus strains. The production in 1200 litre fermenter cultures under serum-free conditions gave antigen yields comparable to the conventional embryonated egg technology. The development of a rapid and efficient purification scheme resulted in a safe high purity vaccine which was at least as immunogenic as conventional egg-derived vaccines in a mouse model. This vaccine has been shown to be safe and highly immunogenic in chimpanzees and to be capable of protecting ferrets against challenge with live virus. Clinical trials have now been initiated in the UK and Austria.

Animals↗