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C Schmid

Publications and source records attributed to C Schmid.

At least 73 records · Page 4Linked to original sources
PubMed2001

[Hyper- and hypothyroidism: which tests are reliable in general practice?].

Thyroid function is evaluated by measuring the serum concentrations of thyroid stimulating hormone (TSH) and free thyroxine (fT4). To confirm a normal thyroid function, a TSH within the normal range is usually sufficient. If hyperthyroidism or hypothyroidism is suspected clinically, the assessment of TSH in association with fT4 is recommended. Additional tests in the evaluation of hyper- and hypothyroidism should be performed depending on the clinically suspected diagnosis. Acquired primary hypothyroidism in the adult can be diagnosed by measurement of TSH and fT4. Additional investigations are usually unnecessary. The indications to perform a thyroid radionuclide scan, thyroid ultrasonography and the determination of thyroid antibodies in patients with primary hyperthyroidism are discussed.

Diagnosis, Differential↗
PubMed2001

Identification and characterization of trypanocides by functional expression of an adenosine transporter from Trypanosoma brucei in yeast.

The causative agents of sleeping sickness, Trypanosoma brucei rhodesiense and T. brucei gambiense, do not synthesize purines de novo but salvage purine bases and nucleosides from their hosts. We used yeast as an expression system for functional characterization of the trypanosomal adenosine transporter TbAT1. A selection of purine analogs and flavonoids were tested for their ability to interfere with adenosine transport, with the aims of identifying (a) trypanocidal TbAT1 substrates, and (b) inhibitors of trypanosomal purine transport. Cordycepin (3'-deoxyadenosine) was a TbAT1 substrate of high activity against T. brucei rhodesiense (IC50 0.2 nM). Inhibitors of mammalian nucleoside transport were not active, while the flavonol silibinin was a potent, noncompetitive inhibitor of TbAT1-mediated adenosine transport in yeast. Silibinin also inhibited melarsen-induced lysis of bloodstream form trypanosomes. IC50 values to T. brucei rhodesiense and to human carcinoma cells were 0.6 and 140 microM, respectively, indicating a good selectivity towards the parasites. Further studies are necessary to elucidate the effects of flavonoids on trypanosomal purine transport and their potential as trypanocides.

Adenosine↗
PubMed2001

Outcome of women is impaired in patients undergoing emergency coronary artery bypass grafting for failed PTCA.

There is an ongoing debate whether female gender is associated with increased cardiovascular morbidity and mortality, especially after coronary interventions. The impact of gender on the outcome of patients undergoing emergency coronary artery bypass grafting (CABG) for failed PTCA was analyzed. Clinical and procedural data of all patients who underwent PTCA and subsequent emergency CABG at our institution from 1989 to 1998 were assessed. During these 10 years, 6681 PTCA procedures were performed, 1312 in women (19.6%). Subsequently, 110 patients underwent emergency CABG of whom 32 were females (29.1%). Postoperatively, 9 women and 5 men died (mortality 12.7%). Women presented with higher age (61.2 +/- 2.1 vs. 58.3 +/- 1.0 years, n.s.), smaller height (1.61 +/- 0.01 vs. 1.76 +/- 0.01 m, p < 0.0001), lower weight (67.7 +/- 2.4 vs. 82.1 +/- 1.2 kg, p < 0.0001), smaller body surface area (1.70 +/- 0.04 vs. 1.98 +/- 0.02 m2, p < 0.0001), and higher comorbidity as expressed by their Cleveland score (7.9 +/- 0.3 vs. 7.1 +/- 0.2, p = 0.013). The risk for failure of PTCA with subsequent emergency CABG was higher in women than in men (2.4% vs. 1.5%, p = 0.012, odds ratio 1.66) as well as for postoperative death (28.1% vs. 6.4%, p = 0.004, odds ratio 4.39). Women had longer in-hospital stays (19.7 +/- 4.2 vs. 12.9 +/- 1.3 days, p = 0.044). Logistic regression analyses found lower weight (p = 0.003), higher number of diseased coronary vessels (p = 0.024) and higher Cleveland score (p = 0.023) to be independent predictors of operative mortality. A Kaplan-Meier model (follow-up 5.3 +/- 2.5 years) showed an increased in-hospital mortality in women (p = 0.0034, log rang test), but a comparable long-term survival. Women had an increased risk for failure of PTCA and a markedly higher operative mortality after emergency CABG. In multivariate analyses, however, gender was not an independent predictor of postoperative death.

Angioplasty, Balloon, Coronary↗
PubMed2001

Pyodera gangrenosum after aortic valve replacement.

A 68-year-old male patient developed pyoderma gangrenosum after elective aortic valve replacement. Treatment with steroids and clofazimine was initiated, which resulted in rapid cessation of the necrotic process. Due to thoracic instability, stabilization of the sternum was performed followed by surgical debridement and atraumatic wound closure. Postoperatively, immunosuppression with cyclosporine A was added; the patient recovered completely. Pyoderma gangrenosum is a potential life-threatening complication that must be considered in patients with severely impaired wound healing after cardiac operation.

Aged↗
PubMed2001

Diagnosis and treatment of nonocclusive mesenteric ischemia after open heart surgery.

BACKGROUND: Acute nonocclusive mesenteric ischemia (NOMI) is a rare but often fatal event after cardiac surgery. METHODS: Twenty patients with ongoing ileus after cardiac surgery despite maximal laxative treatment underwent selective mesenteric angiography. In cases of pathological radiographic findings, papaverine was continuously administered via an intraarterial perfusion catheter. RESULTS: Severe NOMI was confirmed in seven patients (mean lactate: 6.9 +/- 8.3 mg/dL), mild to moderate findings in another seven (mean lactate: 1.4 +/- 1.1 mg/dL). One patient had thromboembolic occlusion of the superior mesenteric artery; five patients demonstrated normal imaging findings. In nine of fourteen patients (64%) treated with papaverine, symptoms improved within hours (defecation occurred after 4-29 hours, mean 13 +/- 8.1 hours). No side effects or complications occurred in connection with the papaverine treatment. The clinical condition of five patients deteriorated. Four patients underwent laparotomy with creation of an ileostomy or colostomy, two of whom presented with severe intestinal ischemia and later died. One patient died prior to laparotomy. CONCLUSIONS: Selective mesenteric angiography with continuous papaverine administration is a simple, fast, and effective diagnostic and therapeutic tool to reduce the need for laparotomy for symptoms of ileus after open-heart surgery.

Aged↗
PubMed2001

Feasibility and risks of heart surgery in very elderly: analysis of 200 consecutive patients of 80 years and above.

A continuing increase in the number of very elderly patients with symptomatic heart disease referred for cardiac surgery has been observed in the past. Since 1990 all patients of 80 years and above have been included in a prospective study. We report on the results of the first 200 consecutive patients (mean age: 82.2+/-2.1 years). Operative procedures ranged from isolated myocardial revascularization and valve replacement to very complex operations. In a majority of patients, the operations had to be performed as urgent or emergency cases because of advanced heart disease. Overall 30 day mortality was 9.5%. More than two thirds of patients needed treatment of perioperative complications. During long-term follow-up, cardiac surgery in octogenarians has proved to be very effective with excellent functional status and quality of life. Because of favorable results elderly patients should not be denied the benefits of cardiac surgery requiring utilization of significant medical resources.

Journal Article↗
PubMed2001

Lung cancer surgery--preoperative risk assessment and patient selection.

Lung resection remains the therapy of choice offering the greatest potential for cure in non spread lung cancer. As these procedures have a significant rate of cardiopulmonary complications, risk assessment and evaluation of functional operability is essential for successful resectional surgery. The most valuable parameters for evaluation of lung function and risk assessment are FEV1, DLCO and VO2max as well as the calculation of predicted postoperative lung function. With preoperative preparatory physical therapy and treatment of comorbidities, also marginal patients may become operable for resectional surgery.

Humans↗
PubMed2001

The impact of anti-endotoxin core antibodies on endotoxin and cytokine release and ventilation time after cardiac surgery.

OBJECTIVES: We hypothesized that a temporary cardiopulmonary bypass (CPB)-induced reduction of endotoxin antibody levels contributes to elevated endotoxin levels and the associated inflammatory consequences, with a significant influence on the postoperative ventilation time period. BACKGROUND: Cardiac surgery using CPB induces a systemic inflammatory response syndrome with an associated risk of increased postoperative morbidity and mortality. METHODS: A total of 100 consecutive patients undergoing elective coronary artery bypass graft surgery using CPB were prospectively investigated. Endotoxin core antibodies (immunoglobulin [Ig] M/IgG against lipid A and lipopolysaccharide), endotoxin, interleukin (IL)-1-beta, IL-6, IL-8 and tumor necrosis factor-alpha were measured serially from 24 h preoperatively until 72 h postoperatively. RESULTS: Eighty-five patients had no complications (group 1), whereas 15 patients required prolonged ventilation (group 2). In both groups, there was a decrease of all antibodies 5 min after CPB onset, compared with baseline values (p < 0.001), an increase of endotoxin and IL-8 peaking at 30 min postoperatively (p < 0.001) and an increase of IL-6 peaking 3 h postoperatively (p < 0.001). In group 2, preoperative antibody levels were lower (p < 0.01)--specifically, the decrease in IgM was significantly stronger and of longer duration (p < 0.002)--and levels of endotoxin (p < 0.001) and IL-8 (p < 0.001) were higher at 30 min postoperatively. CONCLUSIONS: We conclude that an CPB-associated temporary reduction of anti-endotoxin core antibody levels contributes to elevated endotoxin and IL-8 release. Furthermore, lower levels of IgM anti-endotoxin core antibodies were associated with a greater rise in endotoxin and IL-8, as well as prolonged respirator dependence.

Adult↗
PubMed2001

Assessment of selective arterial calcium stimulation and hepatic venous sampling to localize insulin-secreting tumours.

OBJECTIVE: Non-invasive localization modalities such as ultrasound, computed tomography (CT) or magnetic resonance imaging (MRI) often fail to localize insulinomas smaller than 2 cm in diameter. Recent studies have shown that the selective arterial stimulation and hepatic venous sampling (ASVS) technique using intra-arterial calcium as the insulin secretagogue facilitates the regionalization of such occult insulinomas. This study assesses the sensitivity of ASVS in localizing insulin-secreting tumours. SUBJECTS AND METHODS: Eleven consecutive patients (8 women), aged 29-82 years, were studied over the past 4 years at our hospital. Hyperinsulinaemic hypoglycaemia due to an insulin-secreting tumour was proven in all patients. Calcium gluconate (0.025 mEq/kg body weight) was injected directly into the arteries supplying the pancreas and the liver. Insulin levels were measured in samples taken from the right hepatic vein before and 30, 60 and 120 s after each injection. The ASVS technique was performed in all 11 patients; the results were compared with the surgical findings in 10 patients and the autopsy findings in 1 case. The ASVS results were also compared with the findings of other, previously performed imaging modalities. RESULTS: ASVS correctly localized 4 insulin-secreting tumours to the head, 3 to the body, 1 to the tail, 2 to the tail or body of the pancreas and 1 to the liver. Thus, the sensitivity was 100% (11/11) whereas other localization techniques were less sensitive: 7/11 tumours were detected by angiography, 4/8 by endosonography, 3/8 by CT and 1/6 by MRI. Insulinomas (confirmed by histological examination), sized 4-25 mm, were found in 10 patients. All were cured by selective surgery and remained free of hypoglycaemia over the next 1-4 years of follow-up. An insulin-secreting neuroendocrine tumour in the liver was documented in 1 case at autopsy. CONCLUSIONS: Arterial stimulation and hepatic venous sampling is a very sensitive technique for preoperative localization of insulin-producing tumours. It can help to plan minimally invasive surgery and to select an appropriate strategy for patients suffering from malignant tumours in others.

Adult↗
PubMed2001

Melarsoprol refractory T. b. gambiense from Omugo, north-western Uganda.

Culture adapted T. b. gambiense isolated from Northwest Uganda were exposed to 0.001-0.14 microg/ml melarsoprol or 1.56-100 microg/ml DL-alpha-difluoromethylornithine (DFMO). Minimum inhibitory concentrations (MICs) of each drug were scored for each isolate after a period of 10 days drug exposure. The results indicate that T. b. gambiense isolates from Northwest Uganda had elevated MIC values for melarsoprol ranging from 0.009 to 0.072 microg/ml as compared with T. b. gambiense isolates from Cote d'Ivoire with MIC values ranging from 0.001 to 0.018 microg/ml or with T. b. rhodesiense from Southeast Uganda with MIC values from 0.001 to 0.009 microg/ml. All MIC values obtained fell below expected peak melarsoprol concentrations in serum of treated patients. However, it may not be possible to maintain constant drug concentrations in serum of patients as was the case in our in vitro experiments. Importantly, the MIC of 0.072 microg/ml exhibited by one of the isolates from Northwest Uganda was above levels attainable in CSF indicating that this isolate would probably not be eliminated from CSF of treated patients. PCR amplification of the gene encoding the P2-like adenosine transporter followed by restriction digestion with Sfa NI enzyme revealed presence of fragments previously observed in a trypanosome clone with laboratory-induced arsenic resistance. From our findings it appears that reduced drug susceptibility may be one factor for the frequent relapses of sleeping sickness after melarsoprol treatment occurring in Northwest Uganda.

Animals↗
PubMed2001

The phenomenon of treatment failures in Human African Trypanosomiasis.

Treatment of Human African Trypanosomiasis (HAT or sleeping sickness) relies on a few drugs which are old, toxic and expensive. The most important drug for the treatment of second stage infection is melarsoprol. During the last 50 years treatment failures with melarsoprol were not a major problem in Trypanosoma brucei gambiense patients. Commonly a relapse rate of 5-8% was reported, but in recent years it has increased dramatically in some important foci of T. b. gambiense sleeping sickness. Treatment failures for T. b. rhodesiense are much less of a problem apart from some reports between 1960 and 1985 of refractoriness in T. b. rhodesiense patients in East Africa. Analysis of those isolates revealed that their in vitro sensitivity to melarsoprol was one-tenth that of sensitive isolates, and complete failure to cure the infection in the acute mouse model with melarsoprol levels comparable with those in human patients. There was very little indication of resistance in T. b. gambiense isolates from Côte d'Ivoire and NW Uganda. The in vitro melarsoprol sensitivities for populations from relapsing and from curable patients were in the same range. Melarsoprol concentrations in the plasma and cerebrospinal fluid of patients 24 h after treatment did not show any difference between patients who relapsed and those who could be cured. The reason for relapses in the recent T. b. gambiense epidemics are not known. Other parasite-related factors might be involved, e.g. affinity to extravascular sites other than the CNS which are less accessible to the drug. In conclusion, a combination of factors rather than a single one may be responsible for the phenomenon of melarsoprol treatment failures in T. b. gambiense patients.

Africa, Eastern↗
PubMed2001

[Spiral CT of the abdomen: weight-adjusted dose reduction].

AIM OF THE STUDY: The influence of weight-adjusted current application in spiral CT of the abdomen on noise was investigated in a clinical study. PATIENTS AND METHODS: In 77 routine abdominal CT investigations (120 kV, 8 mm, pitch 1.5) the patients were divided into three body-weight groups A (< 60 kg), B (60-80 kg), and C (> 80 kg). The tube current was randomized prospectively in low weight group A, either 125 mA or 150 mA, in middle and high weight groups B and C, 150, 175 or 200 mA, with a tube revolution time of one second. The noise was measured in liver, skeleton muscle, fat tissue, and bladder content for evaluation of image quality. RESULTS: The bodyweight groups differ significantly in noise, e.g., in the liver (150 mA): group A: 15.8 HU, group B: 18.9 HU, group C: 21.5 HU. The increase of tube current (150, 175, 200 mA) within a body weight group resulted in a minor decrease of noise (18.9 HU, 17.6 HU, 17.5 HU, respectively, in group B). There is a good correlation of noise with body weight, body mass index and body cross section, but not with body size. CONCLUSION: A body weight adjusted reduction of tube current is possible without an increase of noise.

Adipose Tissue↗
PubMed2001

A forgotten gauze swab--clinical and legal considerations.

In this report, we will present two cases of retained gauze swabs following open heart surgery. We will discuss diagnostic and treatment strategies as well as medicolegal implications with regard to individual liability and possible penalties according to the German law.

Aged↗
PubMed2001

Treatment strategy and perioperative risk in patients with idiopathic thrombocytopenic purpura undergoing cardiac surgery.

Patients suffering from idiopathic thrombocytopenic purpura undergoing cardiac surgery with extracorporeal circulation may be at increased risk for postoperative bleeding complications. Therefore, different treatment strategies, such as conservative treatment, splenectomy, transfusion of platelet concentrates and therapy with immunoglobulins have been proposed. We report on our experiences with preoperative immunoglobulin treatment in selected patients with special regard on the optimal dosage.

Aged↗
PubMed2001

Noncardiac surgery in patients with left ventricular assist devices.

BACKGROUND: Noncardiac surgery, especially abdominal surgical procedures in patients with long-term mechanical circulatory support and strong anticoagulation, is difficult. METHODS: We report on 14 patients (aged 44 +/- 15 years) with a portable Novacor or HeartMate system, who underwent noncardiac surgical procedures while being supported by the device. RESULTS: The patients underwent 20 procedures for noncardiac reasons; most had an intestinal operation or cholecystectomy. Half of the procedures were performed within 30 days after placement of the device (mean interval, 53 +/- 57 days), only 6 interventions were necessary after 100 days of mechanical support. Complications occurred in 8 patients (57%), 5 of whom had undergone cholecystectomy and had unacceptably high sanguineous drainage losses. CONCLUSIONS: An elective surgical procedure can be performed with an acceptable risk if the operation is carefully managed. Postponing resumption of full anticoagulation is advisable as it may reduce bleeding complications without apparently increasing the risk for thromboembolism. Emergency interventions remain a difficult task.

Adult↗
PubMed2001

Sperm nuclear matrix association of the PRM1-->PRM2-->TNP2 domain is independent of Alu methylation.

Genes or multigenic chromosomal regions are organized by the nuclear matrix into a series of functionally discrete genic domains. Biophysical analysis of the human chromosome 16p13.13 region has shown that the PRM1-->PRM2-->TNP2 protamine containing multigenic locus is bounded by two sperm nuclear matrix attachment regions (MAR). This domain exists in a transcriptionally readied or potentiated (i.e. open) chromatin state when associated with the nuclear matrix. The MAR-bounded PRM1-->PRM2-->TNP2 locus is nestled in an Alu repetitive element dense region. Fluorescence in-situ hybridization, analysis of sperm nuclear matrix/halo preparations showed that the PRM1-->PRM2-->TNP2 domain specifically localizes to the sperm nuclear matrix. This raised the question of whether nuclear matrix association and gene expression in this locus is mediated by Alu methylation. The methylation status of the various Alu elements contained within the human PRM1-->PRM2-->TNP2 locus was therefore assayed. The seven Alu elements tested, including those associated with the matrix attachment regions within the PRM1-->PRM2-->TNP2 locus, were fully methylated in sperm DNA. Conversely, these same Alu repeats were hypomethylated within the erythroleukaemic cell line, K562, which does not express any of the genes from this domain. This study shows that Alu methylation status is independent of attachment of PRM1-->PRM2-->TNP2 locus to the nuclear matrix and that Alu methylation does not play a leading role in the regulation of this domain.

Alu Elements↗
PubMed2001

Prediction of clinical outcome after cardiac surgery: the role of cytokines, endotoxin, and anti-endotoxin core antibodies.

Coronary artery bypass grafting (CABG) using cardiopulmonary bypass (CPB) can lead to a systemic inflammatory response syndrome with organ failure and increased morbidity and mortality. The mechanisms of these findings are still under discussion. We investigated whether anti-endotoxin core antibodies, endotoxin, and proinflammatory cytokines influence the clinical course after cardiac surgery. Seventy-eight patients undergoing CABG using CPB were investigated. Anti-endotoxin core antibodies, endotoxin, interleukin (IL)-6, IL-8, IL-1beta, and TNF-alpha were measured 24 h preoperatively and up to 72 h postoperatively. Patients with a postoperative mechanical ventilation time below 24 h (n = 65; Group A) were compared to patients with prolonged respirator therapy (>24 h; n = 13; Group B). Preoperative antibody levels were significantly lower in Group B (P < 0.001). In this group, antibody levels remained decreased during the observation period (P < 0.001). Endotoxin significantly increased 30' postoperatively in both groups (P < 0.002). The increase in Group B was 3-fold higher (P< 0.001). IL-8 increased postoperatively in both groups, peaking 3 h after surgery (P < 0.001). In Group B, the IL-8 release was significantly higher than in Group A (P < 0.001). IL-6 significantly increased in both groups, reaching its maximum 24 h postoperatively (P < 0.001). No differences between groups were observed. No significant changes of IL-1beta and TNF-alpha were observed. We conclude that anti-endotoxin core antibodies may be predictive of adverse outcome after cardiac surgery. The imbalance between antibodies and endotoxin results in an exaggerated increase in endotoxin and IL-8 with an impact on clinical outcome.

Aged↗