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Biomedical subjects

C Schmidt

Publications and source records attributed to C Schmidt.

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

Tissue engineering of bone: effects of mechanical strain on osteoblastic cells in type I collagen matrices.

The aim of the present study was to investigate the effect of cyclic uniaxial mechanical strain on a human osteoblastic precursor cell line (hFOB 1.19) in three-dimensional type I collagen matrices. Cell seeded collagen constructs were mechanically stretched by a daily application of cyclic uniaxial strain using a special motor-driven apparatus and compared to unstretched controls. Expression of genes involved in cell proliferation and osteoblastic differentiation as well as matrix production were investigated by analyzing the mRNA of histone H4, core binding factor 1, alkaline phosphatase, osteopontin, osteocalcin, and collagen type I (Col I) up to a cultivation period of 3 weeks using real-time PCR. Cyclic stretching of cell seeded Col I matrices at a magnitude occurring in healing bone increased cell proliferation and slightly elevated the expression of nearly all investigated genes over unstrained controls at various time points. It was concluded that mechanical load promotes the proliferation and differentiation of osteoblastic precursor cells in a Col I matrix and that the application of mechanical stimuli may have a beneficial effect on in vitro tissue formation.

Biocompatible Materials↗
PubMed2005

Functionality or aesthetics? A pilot study of music therapy in the treatment of multiple sclerosis patients.

INTRODUCTION: Neuro-degenerative diseases are, and will remain, an enormous public health problem. Interventions that could delay disease onset even modestly will have a major public health impact. The aim of this study is to see which components of the illness are responsive to change when treated with music therapy in contrast to a group of patients receiving standard medical treatment alone. MATERIAL AND METHODS: Twenty multiple sclerosis patients (14 female, 6 male) were involved in the study, their ages ranging from 29 to 47 years. Ten participants formed the therapy group, and 10 the matched control group matched by age, gender and the standard neurological classification scheme Expanded Disability Status Scale (EDSS). Exclusion criteria were pregnancy and mental disorders requiring medication. Patients in the therapy group received three blocks of music therapy in single sessions over the course of the one-year project (8-10 sessions, respectively). Measurements were taken before therapy began (U1), and subsequently every three months (U2-U4) and within a 6-month follow-up without music therapy (U5) after the last consultation. Test battery included indicators of clinical depression and anxiety (Beck Depression Inventory and Hospital Anxiety and Depression Scale), a self-acceptance scale (SESA) and a life quality assessment (Hamburg Quality of Life Questionnaire in Multiple Sclerosis). In addition, data were collected on cognitive (MSFC) and functional (EDSS) parameters. RESULTS: There was no significant difference between the music-therapy treatment group and the control group. However, the effect size statistics comparing both groups show a medium effect size on the scales measuring self-esteem (d, 0.5423), depression HAD-D (d, 0.63) and anxiety HAD-A (d, 0.63). Significant improvements were found for the therapy group over time (U1-U4) in the scale values of self-esteem, depression and anxiety. In the follow-up, scale values for fatigue, anxiety and self-esteem worsen within the group treated with music therapy. DISCUSSION: A therapeutic concept for multiple sclerosis, which includes music therapy, brings an improvement in mood, fatigue and self-acceptance. When music therapy is removed, then scale scores worsen and this appears to intimate that music therapy has an influence.

Adult↗
PubMed2005

Neoplastic heart disease -- the Muenster experience with 108 patients.

BACKGROUND: Tumours of the heart are rare. Different histological subtypes are known. The most common tumour entity is benign cardiac myxoma. Malignant heart tumours are less common. Tumours originating in other organs such as the kidney may also affect the heart by tumour progression via the inferior caval vein. A large experience with surgical treatment of different types of heart tumours is presented. METHODS: Between January 1989 and April 2004, 108 patients with a heart tumour were included in a database. All patients underwent radical surgical resection, except for 2 patients who had malignant lymphoma of the heart. RESULTS: Histological findings included 78 myxomas (72.2 %), and 6 other benign cardiac tumours in 5.6 % of the patients. Primary malignant heart tumours were seen in 10 (9.2 %) and renal cell carcinoma with cardiac involvement in 6 (5.6 %) patients. Eight patients presented with tumour metastases inside the heart (7.4 %). Mean overall survival was 12.7 years for myxoma patients and 5.6 years for patients with other benign heart tumours. Patients with primary malignant heart tumours survived 5.5 years on average. CONCLUSIONS: Heart tumours are rare, but usually life-threatening. Radical surgical resection is the therapy of choice and may offer excellent long-term survival, even in cases with malignant heart tumours.

Adolescent↗
PubMed2005

[Quality of life and sexuality after surgery for rectal cancer--a follow-up study].

BACKGROUND: Previous studies have suggested that sexuality following surgery for rectal cancer is better in women than in men and differs with type of surgery in terms of impact on Quality of Life. However, the findings were inconsistent. The aim of the presented study was to address these issues. METHODS: 570 patients that had undergone surgery for rectal cancer in our department from 1992 to 1999 were included. After determination of survival status questionnaires on Quality of Life were sent to 370 patients one to two years post surgery. We analysed data from 215 patients of which 103 were female and 112 male. 248 patients died during the time observed. Statistical analysis was done with descriptive methods, Kaplan-Meier analysis (log rank test), T-test and analysis of variance using SPSS 11.0 for Windows. RESULTS: Significant differences were seen in symptom scales between men and women. Women scored higher for distress through medical treatment and had higher values for insomnia, fatigue and constipation. Both sexes had impaired sexual life but men had significantly higher values and felt more distressed by the impairment of sexuality than women. For patients receiving abdominoperineal resection sexuality was most impaired. Anterior resection with pouch had a detrimental effect on diarrhoea and treatment strain. CONCLUSION: The study showed that sexuality is influenced by gender and type of surgery and impacts Quality of Life after surgery for rectal cancer. Assessing quality of life with generic and specific instruments is helpful to determine differences between surgical procedures, age, gender, and adjuvant therapy where standard parameters such as survival have their limitations.

Age Factors↗
PubMed2005

Characteristics that promote transmission of Staphylococcus aureus nursing homes in German nursing homes.

OBJECTIVE: To determine factors that influence transmission of Staphylococcus aureus in nursing homes in the Rhine-Neckar region of southern Germany. DESIGN: Ecologic study. SETTING: Forty-seven nursing homes in the region. PARTICIPANTS: Residents of the approached nursing homes who agreed to participate. METHODS: Personal data and swabs of the nares were collected from participants. Swabs were examined for growth of S. aureus. All S. aureus isolates were typed using pulsed-field gel electrophoresis (PFGE). Transmission rates were calculated by dividing the number of transmissions (ie, cases in which two inhabitants shared the same PFGE type) by the number of S. aureus carriers. Characteristics of the nursing homes were correlated with a home's transmission rate. RESULTS: In each nursing home, 12% to 54% of the residents were colonized with S. aureus. The transmission rates for the 47 nursing homes ranged from 0% to 70%. A linear regression model revealed that a stay in the nursing home of longer than 6 months and accommodation in a room with 3 or more beds were positively associated with the transmission rate. Receipt of antibiotics during the 4 weeks preceding the study was negatively associated with transmission. CONCLUSIONS: Stays beyond 6 months and accommodation in rooms with multiple beds are important for the transmission of S. aureus. One way to reduce transmission would be to design facilities with single and double rooms. However, the social needs of the residents must be evaluated and respected.

Cross Infection↗
PubMed2005

Effective systolic orifice area of the aortic valve: implications for Doppler echocardiographic cardiac output determinations.

BACKGROUND: Substantial research using echocardiography has established that stroke volume (SV) or cardiac output (CO) can be measured non-invasively at the level of the aortic valve (AV) with high accuracy. Stroke volume is the product of the velocity time integral occurring at the sampling site and the effective systolic AV orifice area (AVOAeff). Nevertheless, a generally accepted method for the determination of AVOAeff is still lacking. METHODS: Aortic valve OAeff was measured in 228 consecutive patients scheduled for coronary artery surgery. Two widely adopted methods were applied to approximate the constantly changing orifice area of the AV: (1) the circular orifice model (AVOA-CM), and (2) the triangular orifice model (AVOA-TM). Aortic valve OA-CM assumes the shape of a circle as an appropriately time averaged geometrical model, and AVOA-TM takes the shape of an equilateral triangle for granted. RESULTS: The AV was easily imaged by echocardiography in both short- and long-axis views in all patients. Relying on AVOA-CM, AVOAeff was 3.49+/-0.77 cm2. AVOA-TM estimates were 2.80+/-0.55 cm2 (mean+/-SD). The results did not agree (bias analysis). CONCLUSIONS: The echocardiographic measurement of SV or CO at the level of the AV has to be reconsidered.

Aortic Valve↗
PubMed2005

Dexamethasone suppresses eNOS and CAT-1 and induces oxidative stress in mouse resistance arterioles.

Long-term treatment with glucocorticoids is associated with mild to moderate hypertension. We reported previously that downregulation of endothelial NO synthase (eNOS) expression and activity is likely to contribute to this increase in blood pressure. In the present study, we tested the effects of dexamethasone on the vasodilation of microvascular arterioles using implanted dorsal skin-fold chambers in anesthetized C57BL/6J mice. Experiments were performed on control mice or on mice treated with dexamethasone (0.1-3 mg/kg of body wt). Endothelium-dependent vasodilation in response to ACh (0.1-10 microM) was reduced by dexamethasone in a dose-dependent fashion. Comparable inhibition was seen in tissues superfused with 30 microM N(G)-nitro-L-arginine methyl ester. In contrast, endothelium-independent vasodilation in response to S-nitroso-N-acetyl-D,L-penicillamine (10 microM) was not influenced by either dexamethasone or N(G)-nitro-L-arginine methyl ester. Levels of eNOS mRNA in murine hearts and NO(2)(-)/NO(3)(-) in serum were suppressed by dexamethasone (down to 63 and 50% of control values, respectively, at 3 mg/kg of body wt) along with a reduction in eNOS protein to 85.6%. Dexamethasone also concentration dependently reduced the expression of the cationic amino acid transporter-1 in murine hearts and cultured endothelial cells. The suppression by dexamethasone of the ACh-induced vasodilation could be partially reversed by dietary L-arginine (50 mg/kg of body wt) and by dietary vitamin C (10 g/kg of diet). We conclude that suppression by dexamethasone of the endothelium-mediated microvascular vasodilation involves several mechanisms including 1) downregulation of eNOS, 2) downregulation of cationic amino acid transporter-1, and 3) generation of reactive oxygen species. The demonstration that L-arginine and vitamin C can partially offset the effects of dexamethasone on microvascular arterioles suggests the potential clinical usefulness of these agents for the reduction of glucocorticoid-induced hypertension.

Acetylcholine↗
PubMed2005

Etiology and pathogenesis of inflammatory bowel disease.

Despite of scientific efforts during the last decades, etiology and pathogenesis of the two major inflammatory bowel diseases, namely Crohn's disease and ulcerative colitis, remain rather unclear. According to the results of multiple studies it is accepted that the development of either disease is the result of an exaggerated or insufficiently suppressed immune response to a hitherto undefined luminal antigen, probably derived from the microbial flora. This inflammatory process leads to the well-known mucosal damage and therefore a further disturbance of the epithelial barrier function, resulting in an increased influx of bacteria into the intestinal wall, even further accelerating the inflammatory process. However, these immunological disturbances that have been investigated extensively during the past years have to be considered on the genetic background of the individual patient and the environmental factors the patient is exposed to. In this review we will attempt to summarize the current knowledge about risk factors for inflammatory bowel diseases, genetic and environmental factors of IBD and focus on the immunological alterations of innate and acquired immune system underlying Crohn's disease and ulcerative colitis.

Colitis, Ulcerative↗
PubMed2004

Influence of TSH on uptake of [18F]fluorodeoxyglucose in human thyroid cells in vitro.

Recent clinical evidence suggests that positron emission tomography with fluorine-18 fluorodeoxyglucose (FDG-PET) is more accurate in detecting thyroid carcinomatous tissue at high than at low TSH levels. The aim of this study was to determine the influence of TSH on FDG uptake in human thyroid cells in vitro. Monolayers of human thyroid tissue were cultured after mechanical disintegration and enzymatic digestion of samples from patients undergoing surgery for nodular goitre. The purity of thyroid cell preparations was ascertained by immunohistochemical staining for the epithelial antigen KL-1, and their viability by measuring the synthesis of thyroglobulin in vitro. The cells were incubated with 0.8-1.5 MBq FDG/ml uptake medium for 1 h. FDG uptake in thyroid cells was quantified as percent of whole FDG activity per well (% ID) or as % ID in relation to total protein mass. This experimental protocol was subsequently varied to study the effect of incubation time, glucose dependency and TSH. Furthermore, radio-thin layer chromatography was used to identify intracellular FDG metabolites. FDG accumulated in the thyroid cells linearly with time, doubling roughly every 20 min. Uptake was competitively inhibited by unlabelled glucose and decreased to approximately 70% at 100 mg/dl glucose compared to the value measured in glucose-free medium. FDG was intracellularly trapped as FDG-6 phosphate and FDG-1,6-diphosphate. TSH significantly increased FDG uptake in vitro in a time- and concentration-dependent manner: Cells cultured at a TSH concentration of 50 micro U/ ml doubled FDG uptake compared to TSH-free conditions, and uptake after 72 h of TSH pre-incubation was approximately 300% of that without TSH pre-incubation. TSH stimulates FDG uptake by benign thyroid cells in a time- and concentration-dependent manner. This supports the clinical evidence that in well-differentiated thyroid carcinomas, most of which are still TSH-sensitive, FDG-PET is more accurate at high levels of TSH.

Cell Survival↗
PubMed2004

[Implementation of an internal transfer pricing system for anaesthesia services].

Internal transfer pricing system (ITPS) of anaesthesia services is established to guarantee a close connection of delivered service and the budget of the department of anaesthesia. In most cases a time-based system is used with the pricing unit being calculated as the quotient from the enumerator "costs" divided by the denominator "anaesthesia time in minutes". The implementation of a transfer pricing system requires the identification of all relevant costs caused by the department of anaesthesia and a cost centre structure is needed which allocates all costs correctly according to their cause. The regulations regarding cost calculations as defined by the German DRG System should be considered. To generate valid data not only the necessary technical infrastructure is needed, but also detailed training of the staff and plausibility checks are needed to ensure correct and complete data. Subsequent agreements with the hospital administration are necessary in order to adjust the system if extrinsic cost increases occur. This paper gives a step-by-step guidance for the successful implementation of an internal transfer pricing system based on anaesthesia time.

Anesthesia Department, Hospital↗
PubMed2004

[Quantitative ultrasound for the diagnosis of osteoporosis].

Quantitative ultrasound (QUS) methods are promising tools for the assessment of the bone status in osteoporosis. The techniques are based on changes in speed and amplitude of a broadband ultrasound signal propagating through the bone. However, ultrasound propagation through the anisotropic bone is complex and cannot be described in a simple way. The devices are easy to use, inexpensive, portable, do not use ionizing radiation, and therefore have advantages compared to conventional densitometry. This review discusses the technical basics, current research, clinical applications, points of weakness, and future prospects of QUS. For better understanding ultrasound propagation through bone is visualized with a simulation software.

Bone and Bones↗
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

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

[Use of the "c-clamp" in the emergency treatment of unstable pelvic fractures].

UNLABELLED: It was the objective of this investigation to describe the results after stabilisation of pelvic fractures with the pelvic clamp in polytraumatized patients with unstable pelvic ring fractures. PATIENTS: Between 1999 and 2001 11 polytraumatized patients with an average age of 38 years with unstable fractures of the pelvic ring were treated with the "pelvic clamp" (PC). METHOD: The patient's data were analysed retrospectively from the moment they were admitted to our department until 48 hours after the treatment with the pelvic clamp. The following data were observed: -- The time period until the pelvic clamp was placed. -- The mean blood pressure. -- The oxygenation level (PaO (2)/FiO (2) coefficient). -- The number of requested blood units. -- The time period until hemodynamic stabilisation took place. RESULTS: 8 patients survived their injuries. 5 of them were admitted primarily to our department (ISS 39.8, PTS 35), the other 3 were secondarily admitted to our department (ISS 48.3, PTS 39). 3 of 11 patients (27 %) died averaged within the first 45 minutes after admittance. They also were treated in other units before admittance to our department. 8 surviving patients showed -- a hemodynamic stabilisation 6 hours after the treatment with the PC. -- an increase of the mean blood pressure about 25 % 20 minutes after the treatment with the PC. -- a stabilisation of the oxygenation level 6 hours after the treatment with the PC. -- a decrease of the number of requested blood units 6 hours after treatment with the PC. CONCLUSION: Even if the number of patients who were treated is small, the study shows a positive trend in terms of stabilisation of the vital parameters after stabilisation of the pelvic fracture with the pelvic clamp.

Adult↗
PubMed2004

An interleukin 12 p40-IgG2b fusion protein abrogates T cell mediated inflammation: anti-inflammatory activity in Crohn's disease and experimental colitis in vivo.

BACKGROUND AND AIMS: Interleukin-12 (IL-12), a p35/p40 heterodimer, plays a pivotal role in the immune response in Crohn's disease (CD). Since IL-12 p40 dimers act as IL-12 antagonists, we assayed p40 dimer proteins to modulate chronic intestinal inflammation. METHODS: We generated a fusion protein consisting of the IL-12(p40) subunit fused to the constant region of IgG2b. IL-12(p40)-IgG2b was tested in a murine 2,4,6,-trinitrobenzene sulphonic acid (TNBS) colitis model and in lamina propria mononuclear cells (LPMNC) from patients with CD in vitro. RESULTS: Dimeric IL-12(p40)-IgG2b fusion protein bound specifically to the IL-12 receptor. In concentrations <10(-7) M, it acted as an IL-12 antagonist as it inhibited interferon gamma (IFN-gamma) secretion, suppressed proliferation, and increased apoptosis of LPMNC from patients with CD. However, in concentrations >10(-6) M, IL-12(p40)-IgG2b increased IFN-gamma secretion and lymphocyte proliferation thereby acting as an IL-12 agonist. In TNBS colitic mice, IL-12(p40)-IgG2b decreased mortality (10% v 68%), prevented body weight loss, reduced tumour necrosis factor alpha, and increased IL-10 secretion. CONCLUSIONS: The IL-12(p40)-IgG2b fusion protein has dichotomic properties as a specific IL-12 antagonist and selective repressor of mucosal inflammation at low concentration and as an IL-12 agonist at high concentration.

Adult↗
PubMed2004

The oral NK(1) antagonist, aprepitant, given with standard antiemetics provides protection against nausea and vomiting over multiple cycles of cisplatin-based chemotherapy: a combined analysis of two randomised, placebo-controlled phase III clinical trials.

In early clinical trials, the NK(1) receptor antagonist, aprepitant (EMEND(R)) was shown to improve the protection provided by the best available therapy (hereafter referred to as 'standard therapy': a 5-HT(3) receptor antagonist and dexamethasone) against chemotherapy-induced nausea and vomiting over multiple cycles of cisplatin-based chemotherapy. To further study the sustainment of antiemetic efficacy of aprepitant plus standard therapy over more than one cycle of chemotherapy, we examined combined data from the multiple cycles extensions of two phase III clinical trials of oral aprepitant plus standard therapy for the prevention of chemotherapy-induced nausea and vomiting. Data were pooled from two multicentre, randomised, double-blind, placebo-controlled studies with identical design and treatment regimens. Cancer patients receiving a first cycle of cisplatin-based (>or=70 mg/m(2)) chemotherapy were randomised to one of two treatment groups as follows: the standard therapy group received ondansetron 32 mg intravenously (i.v.) and dexamethasone 20 mg on day 1 and dexamethasone 8 mg twice daily (b.i.d.) on days 2-4. The aprepitant group received aprepitant 125 mg, ondansetron 32 mg i.v., and dexamethasone 12 mg on day 1, aprepitant 80 mg and dexamethasone 8 mg on days 2-3, and dexamethasone 8 mg on day 4. Patients had the option to receive the same blinded treatment for up to five additional cycles. The analysis used a combined exploratory endpoint of no emesis and no significant nausea (i.e. nausea which interfered with a patient's normal activities) over the 5 days following cisplatin, for up to six cycles of chemotherapy. A cumulative probabilities approach incorporating a model for transitional probabilities was used to analyse the data. Tolerability was assessed by reported adverse events and physical and laboratory assessments. Baseline characteristics, reasons for discontinuation, and drop-out rates were similar between groups. In every cycle, the estimated probabilities (rates) of no emesis and no significant nausea were significantly higher (P<0.006) in the aprepitant group: in the first cycle, rates were 61% in the aprepitant group (N=516) and 46% in the standard therapy group (N=522), and thereafter, rates for the aprepitant regimen remained higher throughout (59% (N=89) versus 40% (N=78) for the standard therapy, by cycle 6). Repeated dosing with aprepitant over multiple cycles was generally well tolerated. Compared with patients who received standard therapy alone (a 5-HT(3) antagonist plus dexamethasone), those who received aprepitant in addition to standard therapy had consistently better antiemetic protection that was well maintained over multiple cycles of highly emetogenic chemotherapy

Adolescent↗