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C Schmid

Publications and source records attributed to C Schmid.

At least 37 records · Page 2Linked to original sources
PubMed2005

Harvest of the radial artery: technique of the skeletonization and pedicle preparation.

Nowadays, radial artery grafts play a significant role in coronary artery revascularization, however, harvesting techniques are not standardized. We developed various surgical techniques for radial artery harvesting considering the anatomic landmarks of the foramen, including conventional surgery (with scissors and clips) and procedures with ultrasonic scalpel and retrieving the radial artery graft in a pedicle or in a skeletonized manner.

Coronary Artery Bypass↗
PubMed2004

Hypoglycemia in response to glucose and glucagon in insulinoma patients with a negative prolonged fast: functional and morphological properties.

A negative 72-h fast is usually considered to preclude the diagnosis of insulinoma. The aim of this study was to describe the functional and morphological properties of two exceptional patients with an insulinoma who had exhibited pre-operatively a negative 72-h fast. Despite the ability of tumor cells to turn off insulin secretion in response to low plasma glucose during 72 h of fasting, hyperinsulinemic hypoglycemia occurred in both patients in response to stimulation by classical secretagogues. Pre-operatively, both patients underwent oral and iv glucose challenge tests and iv glucagon stimulation test. Insulin secretion was rapidly stimulated by these secretagogues to an exaggerated extent and thereby caused hypoglycemia due to an insulin mass effect. In contrast to the common functional features during suppression and stimulation tests, the tumors differed widely with regard to insulin and proinsulin response to calcium during ASVS tests and morphological properties. In patient 1, the immunohistochemical proinsulin distribution pattern resembled that of normal beta-cells, i.e. the staining was restricted to the perinuclear area; insulin and proinsulin were not stimulated by calcium during the ASVS test. In patient 2, the proinsulin staining pattern was abnormal, i.e. proinsulin was also found in the periphery of tumor cells; insulin and proinsulin were stimulated by calcium. We conclude that normal or exaggerated rather than defective glucose sensing may explain hypoglycemia in these exceptional insulinoma patients. Different functional characteristics of these tumors can be correlated with distinct morphological properties.

Aged↗
PubMed2004

Clinical situations demanding weaning from long-term ventricular assist devices.

OBJECTIVE: Ventricular assist devices are increasingly used to treat patients with acute or chronic end-stage heart failure. We report on circumstances, exemplified on four cases, where a surprisingly favorable clinical course of the patients ultimately demanded early explantation of the device, which was not anticipated prior to its implantation. METHODS: The four patients were provided with implantable (Micromed BeBakey trade mark, Incor trade mark ) and external pneumatically driven (Thoratec trade mark, Excor trade mark ) devices under emergency conditions and were listed for heart transplantation. RESULTS: All four patients had an unexpected recovery of myocardial pump function. After careful diagnostic evaluation, all device components were completely removed without extracorporeal circulation. No stepwise weaning protocol was employed. CONCLUSIONS: Weaning patients from ventricular assist devices after recovery of myocardial pump function can become necessary. Diagnostic evaluation and the implementation of a weaning protocol is still a matter of debate, while complete surgical removal of all device components without extracorporeal circulation is possible with a low risk.

Acute Disease↗
PubMed2004

Antitrypanosomal and antiplasmodial activity of medicinal plants from Côte d'Ivoire.

The antitrypanosomal activity of 101 crude ethanol extracts derived from 88 medicinal plants from Côte d'Ivoire was determined in vitro using Trypanosoma brucei rhodesiense. Of those extracts 8 showed good activity (IC50 values < or =8 microg/ml), 37 revealed a weak activity (IC50 values between 25 and 8.1 microg/ml) and 56 did not show any activity at all (IC50 values >25 microg/ml). The extracts of Enantia polycarpa (Annonaceae) and Trichilia emetica (Meliaceae) were the most promising ones. Their IC50 values were 0.5 and 0.04 microg/ml, respectively, and the selectivity index 616 and 209, respectively. This is the first report of in vitro antitrypanosomal activity of these two plants. Their high activities render them candidates for the isolation of compounds which could develop into new lead structures for drug development programs against African trypanosomiasis. Seven of the tested extracts exhibited an antiplasmodial activity against K1 strain of Plasmodium falciparum with IC50 values below 4 microg/ml. The highest activity was found for Enantia polycarpa stem bark with an IC50 value of 0.126 microg/ml.

Animals↗
PubMed2004

An update on graft-versus-host and graft-versus-leukemia reactions: a summary of the sixth International Symposium held in Schloss Ellmau, Germany, January 22-24, 2004.

The Sixth International Symposium on Graft-versus-Host and Graft-versus Leukemia Reactions was held in Schloss Ellmau (near Garmisch-Partenkirchen, Germany) between January 21 and 24, 2004. A total of 110 invited participants (scientists and clinicians working in the area of allogeneic stem cell transplantation) discussed current topics. Major topics of the 2004 meeting were: clinical results of donor lymphocyte infusions, basic biology, immunogenetics, function and clinical relevance of natural killer cells, haplo-identical stem cell transplantation, immune monitoring and immune modulation. Further highlights were: adoptive immunotherapy, vaccination and antibody-mediated strategies. As can be seen in the summaries of the individual presentations, important advances have occurred in our understanding of GVH and GVL reactions. Each session was followed by an animated discussion, which resulted in new ideas, insights and projects both for basic research and clinical transplantation. This year's symposium ('From Marrow Transplantation to Cell Therapy') was jointly organized by the Ludwigs-Maximilians-University of Munich (Sonderforschungsbereich 455), GSF (National Research Center for Environment and Health) and the EBMT Immunobiology Working Party. The organizers and authors of the conference proceedings would like to extend their gratitude to all participants for sharing their ideas, slides and manuscripts and making this event possible.

Graft vs Host Disease↗
PubMed2004

Cardiac adverse effects associated with psychotropic drugs.

Within the drug safety program in psychiatry AMSP ( Arzneimittelsicherheit in der Psychiatrie), severe adverse drug reactions (ADRs) in psychiatric inpatients are assessed in the naturalistic setting of routine treatment. Currently, 35 psychiatric hospitals and departments are participating. This paper focuses on severe cardiovascular ADRs due to psychotropic medications. Related to the number of patients surveyed (122,562 from 1993 to 2000), these are rare events (68 cases or 0.055 %). Imputed drug classes for probable cases were antidepressants in 0.03 % and neuroleptics in 0.019 %, but other drugs were also involved. Within the group of antidepressants, the risk for a cardiac ADR depends much on the class: SSRIs were never imputed alone, but tricyclic antidepressants were imputed alone in 0.05 %. In the group of antipsychotics, the lowest rate of cardiac ADRs was found for the group of phenothiazines (0.003 %). Cardiovascular risk factors elevated the risk for a cardiac ADR from 0.04 % to 0.14 %. Age as an independent factor did not contribute substantially to the risk for a cardiac ADR. The data of the drug safety program in psychiatry allow some estimate of differential risk rates for cardiac ADRs with different psychotropic drug groups. The results of the project can help clinicians select the appropriate drug for patients at risk to develop cardiac ADRs.

Adult↗
PubMed2004

The place of research and the role of academic surgeons in cardiac surgery.

The development of the discipline of cardiac surgery was, to a large extent, guided by the vision and research of its pioneers. On the basis of their efforts, all the different areas of cardiac surgery were able to evolve including coronary artery bypass grafting, heart valve surgery, surgery of the aorta, congenital heart surgery, surgery for rhythm disorders including the implantation of pacemakers and defibrillators, and surgical treatment of advanced heart failure (for example, heart transplantations and mechanical circulatory support). The continued existence of cardiac surgery and its role in medicine in general will depend, to a significant extent, on the future research activities of its protagonists. Cardiac surgeon-scientists will play a pivotal role since they combine clinical experience with scientific knowledge and intuition which make them able to direct research to topics which will matter in the future. However, research costs money, and state or national funds will be not sufficient to support research as much as is necessary. Funding from third parties such as industry will increasingly be required. Due to this, however, the cardiac surgeon-scientist faces various challenges such as the evaluation of his skill in acquiring funds, conflicts with current ethical standards, conflicts of interest when receiving money from industry, and, as a result of the tough competition in this field, the temptation to commit fraud. The head of a department of cardiac surgery holds an important function as his initiative is decisive for the development of visions for the future and for the employment of surgeon-scientists who pursue visionary research. It will take the combined efforts of surgeon-scientists and departmental heads not only to maintain but to extend the position of cardiac surgery in medicine and society even further.

Biomedical Research↗
PubMed2004

Radical resection of cardiac sarcoma.

We report on our experience with six patients with malignant sarcoma of the heart and show that long-term survival is possible after radical resection. At presentation, the 6 patients (3 male, 3 female) were 45.8 +/- 20 years old. Three patients are alive without evidence of metastases since 29.6 +/- 36.8 months, three patients died after 38 +/- 50.2 months due to distant metastases. Precise preoperative localization of the tumor by means of imaging techniques is very important. In some cases, radical surgery requires an ex situ procedure (autotransplantation). If necessary, the right heart can be resected almost completely, and reconstructed in the form of a Fontan-type circulation. A heart transplantation, as suggested by others, is not justified from our point of view, since prognosis is not better and donor organs are too rare. The results of radical resection are promising, but new concepts for treatment--in particular chemotherapy concepts--for these mostly middle-aged or young patients are required.

Adolescent↗
PubMed2004

ICD implantation -- between necessity and tragedy.

We report on a 42-year-old patient with known dilative cardiomyopathy who underwent placement of a multiple transvenous pacemaker and ICD electrodes, and required removal of all leads via median sternotomy, followed by placement of epicardial electrodes. This experience has led us to question the necessity of the current implantation policies for these systems.

Adult↗
PubMed2004

First experience with rapamycin-based immunosuppression to improve kidney function after heart transplantation.

UNLABELLED: This study was designed to gain initial experience with rapamycin in thoracic organ transplant recipients with severely compromised kidney function, i.e. to see whether and how kidney function will improve with a rapamycin-based immunosuppressive protocol. METHODS: Twelve heart transplant patients were included into the study (serum creatinine > 2.5 mg/dL), with an average time after transplantation of more than 4 years. The calcineurin inhibitor (cyclosporine A = 9, tacrolimus = 3) was reduced by 50 %, and rapamycin added to reach a target level of 8 - 12 ng/dL. Azathioprine was halted, corticosteroid treatment remained unchanged. RESULTS: After implementing the rapamycin-based immunosuppression kidney function improved in all patients within one week. Serum creatinine dropped from 3.1 +/- 0.6 mg/dL to 2.7 +/- 0.5 mg/dL ( p = 0.0004), creatinine clearance increased from 30.4 +/- 11 mL/min to 40.8 +/- 10.5 mL/min ( p = 0.003). This improvement continued until 3 months after the conversion ( p = 0.032). Thereafter, no statistically significant changes were noted up to 6 months posttransplant ( p = 0.41). Serum cyclosporine levels dropped from 180 +/- 40 ng/mL to 132 +/- 46 ng/mL on average ( p = 0.002). Side-effects occurred in 4 patients and were all related to a rapamycin level exceeding 12 ng/mL. CONCLUSIONS: We conclude that transplant patients with impaired kidney function will have an immediate benefit from partially replacing calcineurin inhibitors by rapamycin.

Aged↗
PubMed2004

Successful long-term bridge to transplant in a 5-year-old boy with the EXCOR left ventricular assist device.

We report on a 5-year-old boy who presented with postcardiotomy failure after aortic valve replacement and had to undergo implantation of a Berlin Heart-Excor system since treatment with ECMO did not improve myocardial pump function. After a stormy postoperative course with delayed sternal closure after 9 days, the young boy finally recovered and could be fully mobilized. Until successful heart transplantation after a support interval of 77 days, he experienced no device-related infectious or thromboembolic complications.

Aortic Valve Insufficiency↗
PubMed2004

Regulation of phosphate (Pi) transport and NaPi-III transporter (Pit-1) mRNA in rat osteoblasts.

In osteoblasts only the type III Na(+)-dependent phosphate (NaPi) transporter isoforms Pit-1 and Pit-2 have been identified. We tested the effects of extracellular Pi, Ca(2+) and IGF-I on Na(d)Pi transport and Pit-1 or Pit-2 mRNA expression in rat osteoblastic (PyMS) cells. The v(max) of Na(d)Pi transport was higher in cells kept in Pi-free, serum-free medium for 24 h than in controls at 1 mM Pi (2.47+/-0.20 vs 1.83+/-0.17 nmol/mg protein x 10 min). The apparent affinity constant (K(M)) for Pi remained unchanged. Pi withdrawal for 24 h did not impair cell viability whereas increasing the extracellular Pi to 5 mM resulted in cell death. Pit-1 (but not Pit-2) mRNA was upregulated following Pi deprivation, Ca(2+) treatment or after treatment with 1 nM IGF-I, known to stimulate Na(d)Pi transport and cell proliferation. IGF-I also stimulated Na(d)Pi transport and Pit-1 mRNA in primary rat calvarial osteoblasts. Expression of Pit-1 mRNA in vivo and the coordinate regulation of Pit-1 mRNA and Pi transport in osteoblastic cells suggest that Pit-1 is a candidate transporter of physiological relevance in bone.

Alkaline Phosphatase↗
PubMed2004

[Left ventricular assist devices (LVAD): optional treatment alternative to cardiac transplantation?].

Left ventricular assist devices (LVAD) are used to "bridge" patients with end-stage heart failure until transplantation of a donor heart can be performed ("bridge to transplantation"). However, LVAD support sporadically results in improved cardiac function, and heart transplantation is not necessary even after removal of LVAD in a subset of patients ("bridge to recovery"). Additionally, LVAD appears to be an optional treatment alternative to heart transplantation in patients with contraindication for organ replacement ("destination therapy"). The underlying process has descriptively been termed "reverse remodeling". The molecular basis remains incompletely understood at present, however, some mechanisms have been identified in the past. Alterations of several molecular pathways are involved in the development of chronic heart failure. Some of the pathways appear to be reversible and have been shown to be regulated by LVAD treatment. LVAD lead to lowered cardiac pressure and volume overload followed by decreased ventricular wall tension, reduction of cardiomyocyte hypertrophy, improved coronary perfusion and a decrease of chronic ischemia in the myocardium. Improved coronary flow and myocardial perfusion as well as decreased ventricular wall tension may serve as a possible explanation for changes of the molecular systems involved in the development of chronic cardiac insuffiency. This review focuses on the roles of apoptosis, heme-oxygenase-1 (HO-1), Metallothionein (MT) and the transcription factor NFkkappaB in chronic heart failure after mechanical circulatory support.

Apoptosis↗
PubMed2003

Ex situ resection of primary cardiac tumors.

The prognosis of malignant heart tumors is pessimistic; 50% of patients die within 6 months. No optimal therapy has been established, and standardized therapeutic concepts have not been developed due to the low incidence of this disease. In most cases, chemotherapy and radiotherapy have not shown any survival benefit compared to surgical treatment. Obviously, radical resection of the tumor is the most important determinant for long-term survival. Here, we report on two patients in whom radical resection of heart tumors could be accomplished only after explantation of the heart.

Adult↗
PubMed2003

Arterial revascularization--advantages and pitfalls.

Arterial revascularization is still subject to debate, even though numerous publications have reported presumed advantages of arterial over venous grafts. This brief review summarizes current knowledge on arterial revascularization on a practical basis.

Coronary Artery Bypass↗