PubMed Health⌕ Search

Biomedical subjects

H Sievers

Publications and source records attributed to H Sievers.

At least 19 recordsLinked to original sources
PubMed2006

Use of botanicals in food supplements. Regulatory scope, scientific risk assessment and claim substantiation. 2005.

BACKGROUND/AIMS: In the European Union, an elaborate legal framework regulates botanical products both under food and medicinal law. The decision as to which legal framework applies to an individual product may differ between the Member States. In the case of botanical food supplements, all food law provisions apply to their manufacturing, composition and marketing, including the new claims legislation. METHODS: Elements from EU and national law, scientific and other publications are brought together to investigate how to clarify the differentiation between the use of botanicals for medicinal and health-promoting purposes on a scientific basis. RESULTS: Guidance on the safety assessment and quality evaluation of botanicals is proposed in light of the different approaches described in the scientific literature with particular attention to the concept of long-term use as an integral part of safety evaluation. Guidance on claims substantiation is also included, taking into consideration the proposed legislation, the concept of long-term experience and grading of evidence. CONCLUSIONS: A model for safety and efficacy assessment of botanical food supplements in the EU is proposed, and should be taken into consideration in the development of legislation and scientific research on botanicals.

Animals↗
PubMed2006

Efficacy and tolerability of a spray with Salvia officinalis in the treatment of acute pharyngitis - a randomised, double-blind, placebo-controlled study with adaptive design and interim analysis.

OBJECTIVE: This randomised, double-blind, parallel group phase II/III study with adaptive two-stage design and interim analysis compared the efficacy and tolerability of spray (containing a Salvia officinalis fluid extract) against placebo in the treatment of patients with acute viral pharyngitis. - STUDY PARTICIPANTS: in two study parts, a total of 286 patients with subjective and objective evidence of pharyngitis were randomized. In the first study part 122 patients were enrolled. In the second study part 164 patients were included. The treatment duration per patient was 3 days, including one baseline visit and one final visit. - MAIN OUTCOME MEASURES: Area under Curve for change of throat pain intensity (spontaneous pain), documented every 15 minutes within the first 2 hours after the first application as compared to baseline using a visual analog scale (VAS 100 mm). - RESULTS: Following the interim analyses of the first study part the 15 % spray containing 140 microl sage extract per dose was the most promising preparation for the second study part (main study) whereas for the 30% and the 5% preparation results made superiority over placebo unlikely in the final analysis. Overall, the 15 % spray was significantly superior to placebo for the primary efficacy variable with regard to a reduction of the throat pain intensity score. Only minor side effects such as dry pharynx or burning of mild intensity were seen. - CONCLUSIONS: The efficacy and tolerability profile of a 15 % sage spray indicated that this preparation provides a convenient and safe treatment for patients with acute pharyngitis. A symptomatic relief occurred within the first two hours after first administration and was statistically significantly superior to placebo.

Acute Disease↗
PubMed2004

Endovascular stent-graft implantation in acute traumatic aortic dissection with contained rupture and hemorrhagic shock.

BACKGROUND: Traumatic dissections of the thoracic aorta with consecutive organ ischemia are emergencies with an enormously high mortality despite immediate surgical therapy. Successful therapy of a thoracic aortic aneurysm by percutaneous implantation of a stent graft prosthesis was first reported in 1994. In recent years endovascular methods have been used increasingly for the treatment of acute aortic syndromes. CASE REPORT: After a traffic accident, a 33 year old motorcycle rider was admitted to our emergency unit conscious with clinical signs of hemorrhagic shock. His lower extremities were pulseless and paraplegia of the legs had already developed. An immediate angio-CT scan demonstrated a contained rupture of the aortic wall with mediastinal hematoma caused by a dissection beginning in the aortic arch. In the cathlab the right femoral artery was exposed and an angiography was performed showing a complete interruption of aortic blood flow caused by the transection. Under angiographic control an endovascular self-expanding nitinolstent (Talent Stent Graft, Medtronic) was implanted into the descending aorta. After moderate balloon inflation at the proximal entry, the rupture was completely closed and perfusion was restituted. The further clinical course was complicated by rhabdomyolysis necessitating additional subtotal arm amputation. Spinal ischemia resulted in persisting paraplegia of the legs. CONCLUSION: An urgent treatment of a contained rupture of the descending aorta with consecutive organ ischemia by endovascular implantation of stent graft prosthesis is technically possible. Advantages are a less invasive procedure and rapid restitution of blood flow.

Accidents, Traffic↗
PubMed2004

The Impella Recover microaxial left ventricular assist device reduces mortality for postcardiotomy failure: a three-center experience.

BACKGROUND: We evaluated patient outcomes and complications associated with the microaxial Impella Recover left ventricular assist device (Impella Cardiosystems AG, Aachen, Germany) for postcardiotomy low-output syndrome. This low-cost device is inserted across the aortic valve through a 10-mm vascular graft sewn to the ascending aorta. METHODS: Impella patients were compared with 198 patients treated with an intraoperative intra-aortic balloon pump between January 2000 and December 2002. Three risk scores were used: the Hausmann score, the Texas Heart Institute score, and the Cleveland intensive care unit score. Between September 2001 and March 2003, 24 patients were treated with the Impella Recover for low-output syndrome. Before device insertion, 21 could not be separated from cardiopulmonary bypass, and 3 had postoperative hemodynamic instability despite high-dose catecholamines. Sixteen were treated with the Impella and intra-aortic balloon pump and 8 with the Impella alone (no intra-aortic balloon pump because of peripheral vascular disease or because deemed unnecessary). RESULTS: No technical problems with device insertion occurred. Pump flow was 3.3 +/- 0.7 L/min at 28,000 +/- 4500 RPM. Support time was 61 +/- 56 hours (range, 7-228 hours). Four devices required repositioning. One device failed (leaking purge line) and was removed. Hemolysis was minimal (lactate dehydrogenase levels of 540 +/- 260 U/dL for Impella survivors). Mortality for Impella patients was 54% (13/24), similar to that for high-risk intra-aortic balloon pump patients (Hausmann score > or =2 [57%], intensive care unit score > or =2 [51%], Texas Heart Institute score > or =0.75 [55%], and cardiac index < or =2.3 [45%]). Cardiac output data were available in 19 Impella patients. Impella patients able to increase their cardiac output to 1 L/min or more above the pump flow of the Impella Recover had a 10% (1/10) mortality, versus 88% (8/9) in patients with a residual cardiac function of 1 L/min or less (P =.001). Comparison of high-risk intra-aortic balloon pump patients with Impella patients with residual cardiac function of 1 L/min or more showed a significant reduction in mortality, regardless of the high-risk definition used. Residual cardiac function was the strongest predictor of survival in Impella patients. CONCLUSIONS: The Impella Recover device provides 3 to 4 L/min flow. It improves survival in patients with low-output syndrome if the heart is able to pump 1 L/min or more above device flow.

Aged↗
PubMed1994

Reduction of homologous blood requirements by blood-pooling at the onset of cardiopulmonary bypass.

This study was done to investigate whether an intraoperative autologous blood donation (pooling) at the onset of cardiopulmonary bypass can reduce homologous blood requirements during and after operations for myocardial revascularization. Ninety patients were assigned equally to two groups. In group C, serving as the control group, cardiopulmonary bypass was done with a membrane lung primed with 1500 ml of Ringer's solution. The cardiopulmonary bypass flow ranged between 2.4 L/min per square meter in normothermia and 1.5 L/min per square meter in moderate hypothermia of 30 degrees to 32 degrees C. In group P the same devices were used as in group C; however, at the onset of cardiopulmonary bypass 500 to 1000 ml of heparinized blood was "pooled" in a bag and substituted by the same volume of Ringer's solution. The lower hemodilution limit was set to a hematocrit value of 20%. The pooled blood was retransfused after the aorta was decannulated. The main parameter of interest was the total volume of red cell concentrates and fresh frozen plasma required during the operation and the subsequent stay in the hospital. The results were that group C received on average 792 +/- 639 ml and group P 337 ml +/- 382 ml of red cell concentrates. Very small amounts of fresh frozen plasma were used on average: group C, 56 ml; group P, 0 ml. These differences were highly significant (p < 0.001). Remarkably, 44% of patients in group P did not require any homologous blood products compared with 16% in group C. In conclusion, modern oxygenators, which provide sufficient oxygen transport capacity, make it feasible to decrease the hematocrit to 20% by "pooling" blood at the beginning of cardiopulmonary bypass and replacing it with saline solution. This procedure led to a highly significant saving of homologous blood.

Blood Transfusion↗
PubMed1991

[Young patient with left brain infarct and transient right sided hemiparesis in cardiac papillary fibroelastoma].

This is a case report of a 25-year-old female with recurrent episodes of transient cerebral ischemia accompanied by transient hemiparesis. Cardiac ultrasound examination revealed a small left-ventricular tumor located between the chordae tendineae. The echocardiographic finding was subsequently confirmed by surgery. The entire tumor was removed and the mitral valve remained intact. Due to the histological and immunohistochemical findings a papillary fibroelastoma was diagnosed. The early and late postoperative course was without event.

Adult↗
PubMed1990

Prospective randomized clinical trials of new quinolones versus beta-lactam antibiotics in lower respiratory tract infections.

In four prospective randomized clinical trials between November 1983 and March 1988, we studied 270 patients with severe bacterial infections, mainly lower respiratory tract ones. We compared ciprofloxacin and imipenem/cilastatin in the first study, ciprofloxacin and ofloxacin in the second study, ciprofloxacin and ticarcillin/clavulanic acid in the third study, and ofloxacin and cefpirome in the fourth study. A total of 90 pneumonias, 139 LRTIs, 22 septicaemias and 19 other bacterial infections were treated; the dominant pathogens were Pseudomonas aeruginosa and enterobacteria. Clinical success rates were high; cure or improvement was registered in 89% of the patients on ciprofloxacin, 89% on ofloxacin and 85% on beta-lactams. Treatment failures occurred mainly in ICU patients with terminal underlying diseases. Bacteriologically, eradication rates were high for enterobacteria and Staphylococcus aureus, but a relatively high persistence rate was seen for P. aeruginosa due to increased resistance and/or specific type and location of the infections. The incidence of side-effects was relatively high (23%-29%) which was related to careful monitoring. Adverse effects were group-specific (CNS reactions with quinolones, diarrhoea with beta-lactam antibiotics).

Cilastatin↗
PubMed1987

Tissue changes induced by intraocular lenses. A histopathologic study.

The histopathologic findings in autopsy and surgically enucleated eyes are described. Tissue atrophy and inflammatory reaction can be demonstrated in every eye examined in our laboratory. Scanning electron microscopy was used to detect tissue formation on intraoccular lenses.

Atrophy↗
PubMed1984

Foreign-body reaction against intraocular lenses.

We studied five intraocular lens implants removed for various reasons by light, transmission, and scanning electron microscopy. Four implants were Binkhorst four-loop lenses; the fifth was of an unidentified type. The durations of implantation ranged from three to 36 months, with an average of 14 months. The surface of all implants was covered with a thin acellular membrane of unknown nature. On top of this membrane we found different types of cells that are normally involved in a foreign-body reaction. These included fibroblasts, histiocytes, epithelioid cells, and multinucleated foreign-body giant cells, in all stages. Our findings suggested that iris-fixed artificial lenses are subject to a defensive cellular reaction by the host. The limited extent of this reaction was correlated with the success of the implant.

Adult↗
PubMed1983

Distribution of tritium label in the neonate rat brain following intracisternal or subcutaneous administration of [3H]6-OHDA. An autoradiographic study.

The present report describes the distribution of tritium label after injection of newborn rats with [3H]6-hydroxydopamine ([3H]6-OHDA). The animals were injected either intracisternally (i.c.) or subcutaneously (s.c.), with or without pretreatment with nomifensine, which blocks the high-affinity uptake of both noradrenaline (NA) and dopamine (DA), and sacrificed at intervals from 40 min to 24 h post-injection (p.i.). In i.c. injected animals, tritium label is demonstrable as early as 40 min p.i. in neurons of all known NA and DA cell groups. In NA neurons, it is taken up into cell body, dendrites, preterminal and terminal axons. The intensity of neuronal labeling is highest within the first 4 h p.i. and decreases in most neurons with longer postinjection intervals. A significant proportion of both NA and DA neurons degenerate beginning 6 h p.i., the majority show morphological signs of the axon reaction 24 h p.i. Uptake of [3H]6-OHDA into serotonergic and non-catecholaminergic neurons is not demonstrable. [3H]6-OHDA is accumulated by the following extraneuronal cells of the CNS: ependymal cells, epithelial cells of the choroid plexus, subependymal macrophages, smooth muscle cells in the wall of large intraparenchymal blood vessels, meningeal cells and glial cells. The time course of accumulation and disappearance of the label varies among these extraneuronal elements. The meningeal cells show the highest labeling intensity and degenerate within 24 h p.i. After pretreatment of the animals with nomifensine, the uptake of [3H]6-OHDA into NA and DA neurons is totally blocked; by contrast uptake of the labeled drug into extraneuronal cells is not prevented. These findings show that [3H]6-OHDA is not only accumulated by neurons possessing the high-affinity uptake for NA or DA, but by numerous other, extraneuronal cells which also participate in the metabolism of catecholamines.

Animals↗
PubMed1982

Supravalvular pulmonary stenosis after anatomic correction of transposition of the great arteries: causes and prevention.

Twenty-two patients who underwent anatomic correction of transposition of the great arteries at the arterial level at the age of 8 weeks to 14 years were reinvestigated 1-4.6 years (mean 2.0 years) after operation. A Dacron tube was used to bridge the gap between the proximal pulmonary route and the distal pulmonary artery in four patients and a tube made of homologous dura mater (2.5 cm in diameter) was used in 18. The nonvalved conduit was placed on the right side of the ascending aorta in nine patients and on the left side in 13. Supravalvular pulmonary stenosis with a gradient of 45-95 mm Hg was found in three patients, all of whom had had the conduit placed on the right side. There was normal growth of the pulmonary artery proximal and distal to the stenotic area. Operation for the relief of the stenosis with insertion of a pericardial patch across the stenosed area was performed in two patients. We conclude that supravalvular pulmonary stenosis after anatomic correction of transposition of the great arteries occurs only when the new pulmonary artery is placed on the right side of the ascending aorta and that the use of a large tube of dura mater appears to allow for rapid growth in early life.

Adolescent↗
PubMed1981

Comparison of ftorafur with 5-fluorouracil in combination chemotherapy of advanced gastrointestinal carcinoma.

The aim of the study was to compare the combination 5-FU-carmustine with ftorafur-carmustine in the treatment of advanced gastrointestinal cancer. To this end, a prospective, multicenter, randomized trial was initiated. Part I of this trial showed that similar response rates can be obtained with 5-FU-carmustine and ftorafur-carmustine in 109 patients (32.7% versus 26.3%). However, median survival was better in patients treated with 5-FU-carmustine (307 days versus 163 days). Part II of the trial revealed that neither a higher dosage of ftorafur (2 g/m2/day X 5 days) nor the addition of vincristine to both regimens changed the previously obtained results significantly. Again, median survival was found to be better in patients treated with 5-FU combination chemotherapy (304 days versus 144 days). Both the 5-FU and the ftorafur combination were tolerated reasonably well. The results suggest that combination chemotherapy including 5-FU is superior to ftorafur at the applied dosages in terms of survival.

Adult↗