Search PubMed⌕ Search

Biomedical subjects

T Schneider

Publications and source records attributed to T Schneider.

At least 91 records · Page 5Linked to original sources
PubMed2001

[Benign, pulmonary metastatic leiomyoma of the uterus].

Pulmonary nodules resected in 10 patients were histologically classified as benign metastatic leiomyoma of the uterus. Hysterectomy because of myoma had been performed between 0 and 24 years earlier (median 14.9 years). Between 1 and 27 nodules were found in one or both lungs. Patients presenting with a single nodule had it resected with diagnostic intent and were followed up. Multiple nodules were resected if the loss of parenchyma was tolerable; otherwise, one lesion was resected for diagnosis. In some cases antihormonal therapy was performed postoperatively. The median duration of follow-up was 4.7 years. In this time, no local complication occurred, and no patient died of this disease. Apparently, benign metastatic leiomyoma of the uterus biologically shows benign behaviour. New manifestation or progressing growth of non-resected lesions does occur, however. Consequently, regular follow-up is required. Local complications indicate surgical intervention.

Adult↗
PubMed2001

[Technology integration and process management. Concept and implementation of a new platform for simultaneous diagnosis and therapy of acutely ill and injured patients and for elective computer assisted surgery (CAS)].

Modern imaging and computer technology gain more and more importance in surgery. This is true for elective and emergency diagnosis and treatment. However integration of technology and optimization of process management is severely behind. A new diagnostic-therapeutic platform should balance this deficit. The platform is composed of a fully equipped operation room environment with integrated high end computer-tomography with navigation, a digital subtraction angiography and an OR- and imaging-table particularly developed for this set-up. The platform may be used for elective diagnosis, for diagnosis and therapy in polytraumatized patients in one and the same location (one stop shop) and for computer assisted surgery (CAS). Bringing the technology to the patient and not the patient to the technology can save time consuming and potentially dangerous transports and expensive personnel can be reduced. Navigation-technology and high quality intra-operative imaging expand the spectrum of minimally invasive surgery.

Diagnostic Imaging↗
PubMed2001

[Sachse internal urethrotomy. Is erectile dysfuction a possible complication?].

Erectile dysfunction is reported to be a complication of direct-vision internal urethrotomy by some authors in 2.2-10.6% of cases. It is caused by injury to the cavernous nerve by direct severance with the cutting blade, late fibrosis after extravasation and infection, or by a shunt between the corpora cavernosa and corpus spongiosum. The aim of this examination was to evaluate all internal urethrotomy patients from 1990 to 1999, regarding this kind of complication. Of 184 patients, 111 had to be excluded due to preexisting erectile dysfunction, malignancy, age over 75 years, or open surgery of the urethra before internal urethrotomy. Five patients died. Of 184,68 patients did not have erectile problems before the operation and only one complained about erectile dysfunction following direct-vision internal urethrotomy. Further examination showed an impaired arterial inflow in both arteriae penis profunda; cavernosography could not prove a shunt between the corpora cavernosa and corpus spongiosum. Erectile dysfunction is a possible complication of direct-vision internal urethrotomy. External sphincterotomy at the 3- and 9-o'clock position, urethrotomy after injury or open reconstructive surgery of the urethra, and urethrotomy of long and dense strictures as well as a dilatation over 22 Chr. are known to cause this complication. To inform the patient concerning this kind of complication is recommended before urethrotomy.

Adolescent↗
PubMed2001

Vesicle-mediated trafficking of parasite proteins to the host cell cytosol and erythrocyte surface membrane in Plasmodium falciparum infected erythrocytes.

During the development of the asexual stage of the malaria parasite, Plasmodium falciparum, the composition, structure and function of the host cell membrane is dramatically altered, including the ability to adhere to vascular endothelium. Crucial to these changes is the transport of parasite proteins, which become associated with or inserted into the erythrocyte membrane. Protein and membrane targeting beyond the parasite plasma membrane must require unique pathways, given the parasites intracellular location within a parasitophorous vacuolar membrane and the lack of organelles and biosynthetic machinery in the host cell necessary to support a secretory system. It is not clear how these proteins cross the parasitophorous vacuolar membrane or how they traverse the erythrocyte cytosol to reach their final destinations. The identification of: (1) a P. falciparum homologue of the protein Sar1p, which is an essential component of the COPII-based secretory system in mammalian cells and yeast and (2) electron-dense, possibly coated, secretory vesicles bearing P. falciparum erythrocyte membrane protein 1 and P. falciparum erythrocyte membrane protein 3 in the host cell cytosol of P. falciparum infected erythrocytes recently provided the first direct evidence of a vesicle-mediated pathway for the trafficking of some parasite proteins to the erythrocyte membrane. The major advance in uncovering the parasite-induced secretory pathway was made by incubating infected erythrocytes with aluminium tetrafluoride, an activator of guanidine triphosphate-binding proteins, which resulted in the accumulation of the vesicles into multiple vesicle strings. These vesicle complexes were often associated with and closely abutted the erythrocyte membrane, but were apparently prevented from fusing by the aluminium fluoride treatment, making their capture by electron microscopy possible. It appears that malaria parasites export proteins into the host cell cytosol to support a vesicle-mediated protein trafficking pathway.

Animals↗
PubMed2001

Does penile size in younger men cause problems in condom use? a prospective measurement of penile dimensions in 111 young and 32 older men.

OBJECTIVES: Young men often complain about problems with condom use, but very little information exists about the influence of men's age on penile dimensions and therefore on possible problems in the use of the most important means of contraception in the young. METHODS: We performed a prospective measurement of penile dimensions in 111 men,18 to 19 years old (group A), and in 32 men, 40 to 68 years old (group B). We measured penile length and width in the flaccid state and after visual and manual self-stimulation in group A and after intracavernous injection of prostaglandin E(1) in group B. RESULTS: The mean flaccid length in group A (8.60 cm) and group B (9.22 cm) was significantly different. The mean erect length in group A (14.48 cm) and group B (14.18 cm) was not significantly different. The mean flaccid width at the base was significantly different between group A (3.08 cm) and group B (2.87cm), but the mean flaccid width at the glans was not (group A, 3.02 cm; group B, 3.01 cm). The mean erect width at the base (group A, 3.95 cm; group B, 3.50 cm) and the erect width of the glans (group A, 3.49 cm; group B, 3.32 cm) were significantly different. CONCLUSIONS: Our assumption that the problems young men experience with condom use may be because of smaller penises could not be proved. To address the problems in condom use in younger men, a larger variety of condom sizes and better information about condom use may be useful.

Adult↗
PubMed2001

Optimal Response to Cardiac Arrest study: defibrillation waveform effects.

INTRODUCTION: Advances in early defibrillation access, key to the "Chain of Survival", will depend on innovations in defibrillation waveforms, because of their impact on device size and weight. This study compared standard monophasic waveform automatic external defibrillators (AEDs) to an innovative biphasic waveform AED. MATERIAL AND METHODS: Impedance-compensated biphasic truncated exponential (ICBTE) and either monophasic truncated exponential (MTE) or monophasic damped sine (MDS) AEDs were prospectively, randomly assigned by date in four emergency medical services. The study design compared ICBTE with MTE and MDS combined. This subset analysis distinguishes between the two classes of monophasic waveform, MTE and MDS, and compares their performance to each other and to the biphasic waveform, contingent on significant overall effects (ICBTE vs. MTE vs. MDS). Primary endpoint: Defibrillation efficacy with < or =3 shocks. Secondary endpoints: shock efficacy with < or =1 shock, < or =2 shocks, and survival to hospital admission and discharge. Observations included return of spontaneous circulation (ROSC), refibrillation, and time to first shock and to first successful shock. RESULTS: Of 338 out-of-hospital cardiac arrests, 115 had a cardiac aetiology, presented with ventricular fibrillation, and were shocked by an AED. Defibrillation efficacy for the first "stack" of up to 3 shocks, for up to 2 shocks and for the first shock alone was superior for the ICBTE waveform than for either the MTE or the MDS waveform, while there was no difference between the efficacy of MTE and MDS. Time from the beginning of analysis by the AED to the first shock and to the first successful shock was also superior for the ICBTE devices compared to either the MTE or the MDS devices, while again there was no difference between the MTE and MDS devices. More ICBTE patients achieved ROSC pre-hospital than did MTE patients. While the rates of ROSC were identical for MTE and MDS patients, the difference between ICBTE and MDS was not significant. Rates of refibrillation and survival to hospital admission and discharge did not differ among the three populations. CONCLUSIONS: ICBTE was superior to MTE and MDS in defibrillation efficacy and speed and to MTE in ROSC. MTE and MDS did not differ in efficacy. There were no differences among the waveforms in refibrillation or survival.

Adult↗
PubMed2001

[Blood donation. Job description of the function of a physicion in a district subdivision].

Following the 1995 national reorganization of the transfusion system, the Nord Pas de Calais blood transfusion center has modified its blood collection organization, with the creation of four districts divided into three or four subdivisions. This change was part of Quality Assurance implementation in the center. This article provides the job description for a physician in charge of such a subdivision as well as the method chosen to design this description (inspired by the diagram of Hijman). This job was conceived as an association of human skills knowledge with the strategy of the blood center. In addition to his medical activity, the district subdivision physician becomes a manager and an organizer. The method used highlights the participation of all disciplines involved in blood donation.

Blood Banks↗
PubMed2001

Preliminary results of active specific immunization with modified tumor cell vaccine in glioblastoma multiforme.

OBJECT: Treatment for glioblastoma multiforme has failed to show any progress for decades. While specific immunization with tumor cells modified with Newcastle-Disease-Virus (NDV) has been reported successful in some extracerebral tumors, its effect on glioblastoma is unknown. We report on 11 patients, in whom this approach was analyzed. METHODS: A vaccine was produced from autologous tumor cell cultures of 11 patients with glioblastoma. After completed surgery and radiotherapy an intracutaneous vaccination was performed 4 times with a 2 week interval and finally after 3 months. Local reactions, general side effects and survival were monitored closely. RESULTS: The local reaction of the skin after injection of vaccine increased from 1.67 to 4.05 cm2 in 8 weeks. The skin reaction after parallel injection of inactivated, untreated tumor cells increased from 0.11 to 1.09 cm2. The median survival was 46 weeks (mean 60 weeks). No side effects were noted. CONCLUSION: Active specific immunization with NDV-modified glioblastoma cells produced a noticeable peripheral immune response. In this preliminary series survival of patients was not significantly longer after active specific immunization than after combined treatment of surgery, radiotherapy and chemotherapy. As there were no side effects, however, active specific immunization may be considered an alternative in the management of glioblastoma.

Adult↗
PubMed2001

Impact of surgery on survival in palliative patients with metastatic colorectal cancer after first line treatment with weekly 24-hour infusion of high-dose 5-fluorouracil and folinic acid.

BACKGROUND: In palliative first-line treatment of colorectal cancer, the secondary resection of distant metastases after downstaging has constantly gained in importance. The objective of this prospective study was to examine the tumor response rate, the toxicity, the median survival time and the prognostic impact of metastatic resection after downstaging of consecutively enrolled patients with primary nonresectable colorectal cancer treated with once weekly 24-hour (24-h) infusion of high-dose 5-fluorouracil (5-FU) and folinic acid. PATIENTS AND METHODS: Between January 1995 and July 1997, 53 consecutive patients with primary nonresectable metastases were recruited for a prospective phase II study. The patients received in out-patient care 500 mg/m2 folinic acid in the form of a 1-2-hour infusion followed by 2600 mg/m2 5-FU administered as a 24-h infusion once weekly. One treatment cycle comprised six weekly infusions followed by a two week rest. Three cycles were administered, and in the event of complete remission (CR) or partial remission (PR) and good tolerability, a fourth cycle was undertaken. Thereafter, the possibility of performing a curative metastatic resection was investigated. RESULTS: Of the 53 patients treated, 7 showed a CR (13%), 15 patients a PR (28%), 26 patients stable disease (SD) (49%), and 5 patients progressive disease (PD) (10%). As the main symptom of toxicity, diarrhea (CTC grade 3 + 4) was observed in 11 patients (21%), followed by leucocytopenia (CTC grade 3 + 4) in 2 patients (4%), and the hand-foot syndrome in 1 patient (2%). The median survival time was 17 months with a median follow-up of 41 months (range: 28-59 months). In 9 patients (17%), a secondary metastatic resection was considered; in 6 patients (11%) curative resection was performed, and 4 patients (8%) showed no evidence of disease for at least three years. CONCLUSION: In this phase II study, we have been able to show prospectively that, after downstaging by palliative treatment using a weekly 24-h infusion of high-dose 5-FU and folinic acid, secondary curative metastatic resection was technically feasible in 11% of the patients. For some of these patients, long-term survival is therefore possible. Secondary metastatic resection should be carried out in close interdisciplinary cooperation, and should be further investigated in prospective phase III studies.

Aged↗
PubMed2001

Quantitative testing of liver function in relation to fibrosis in patients with chronic hepatitis B and C.

BACKGROUND/AIM: Quantitative tests of liver function may be superior to conventional tests to assess the prognosis of patients with liver diseases. There are insufficient data from quantitative testing of liver function (QTLF) for patients with chronic hepatitis B and C, particularly with regard to fibrosis. Therefore, we applied a broad panel of QTLF to these patients. METHODS: Three hundred and sixty-seven consecutive patients with chronic hepatitis B or C underwent liver biopsy and QTLF, which included tests for hepatic metabolism (aminopyrine breath test, galactose elimination capacity) and for hepatic perfusion (sorbitol clearance, indocyanine green clearance). QTLF values were correlated with liver histology (grading and staging for inflammation and fibrosis) and Child-Pugh classification for liver cirrhosis. RESULTS: In patients with no and moderate fibrosis, metabolic liver function was significantly decreased, whereas hepatic perfusion remained normal. Severe fibrosis and cirrhosis showed a significant decline in all QTLFs. Hepatic inflammation only reduced metabolic liver function, irrespective of the inflammatory grade. Viral etiology and HCV genotypes did not change QTLF. CONCLUSIONS: In summary, viral damage compromises hepatic metabolism before perfusion. Therefore, tests of metabolic liver function (aminopyrine breath test, galactose elimination capacity) should be useful to search for drugs that restore liver function in viral hepatitis irrespective of the fibrosis stage.

Adult↗
PubMed2001

Functional coupling between 'R-type' Ca2+ channels and insulin secretion in the insulinoma cell line INS-1.

Among voltage-gated Ca2+ channels the non-dihydropyridine-sensitive alpha1E subunit is functionally less well characterized than the structurally related alpha1A (omega-agatoxin-IVA sensitive, P- /Q-type) and alpha1B (omega-conotoxin-GVIA sensitive, N-type) subunits. In the rat insulinoma cell line, INS-1, a tissue-specific splice variant of alpha1E (alpha1Ee) has been characterized at the mRNA and protein levels, suggesting that INS-1 cells are a suitable model for investigating the function of alpha1Ee. In alpha1E-transfected human embryonic kidney (HEK-293) cells the alpha1E-selective peptide antagonist SNX-482 (100 nM) reduces alpha1Ed- and alpha1Ee-induced Ba2+ inward currents in the absence and presence of the auxiliary subunits beta3 and alpha2delta-2 by more than 80%. The inhibition is fast and only partially reversible. No effect of SNX-482 was detected on the recombinant T-type Ca2+ channel subunits alpha1G, alpha1H, and alpha1I showing that the toxin from the venom of Hysterocrates gigas is useful as an alpha1E-selective antagonist. After blocking known components of Ca2+ channel inward current in INS-1 cells by 2 microM (+/-)-isradipine plus 0.5 microM omega-conotoxin-MVIIC, the remaining current is reduced by 100 nM SNX-482 from -12.4 +/- 1.2 pA/pF to -7.6 +/- 0.5 pA/pF (n = 9). Furthermore, in INS-1 cells, glucose- and KCl-induced insulin release are reduced by SNX-482 in a dose-dependent manner leading to the conclusion that alpha1E, in addition to L-type and non-L-type (alpha1A-mediated) Ca2+ currents, is involved in Ca2+ dependent insulin secretion of INS-1 cells.

Alternative Splicing↗
PubMed2001

A qualitative analysis of women's satisfaction with primary care from a panel of focus groups in the National Centers of Excellence in Women's Health.

Health issues unique to women and differences in healthcare experiences have recently gained attention as health plans and systems seek to extend and improve health promotion and disease prevention in the population. Successful efforts focused on enhancing quality of care will require information from the patient's perspective on how to improve such services to best support women's attempts to lead healthy and productive lives. The National Centers of Excellence in Women's Health program (CoE), sponsored by the Office on Women's Health within the Department of Health and Human Services, is based on an integrated model uniting research, training, healthcare, and community education and outreach. To examine women's concept and definitions of healthcare quality, 18 focus groups comprising 137 women were conducted nationwide on experiences and attributes of healthcare that women value in primary care. Following the focus groups, a woman-focused healthcare satisfaction instrument was developed for the purpose of assessing and improving healthcare delivery. We describe the qualitative results of the focus group study.

Adolescent↗
PubMed2001

R-wave detection by subcutaneous ECG. Possible use for analyzing R-R variability.

BACKGROUND: Atrial arrhythmia (AA) discrimination remains a technological challenge for implanted cardiac devices. We examined the feasibility of R-wave detection by a subcutaneous far field ECG (SFFECG) and analysis of these signals for R to R variability as an indicator of atrial arrhythmia (AA). METHODS: Surface ECG and SFFECG (from the pacemaker pocket) were recorded in sixteen patients (61.5 +/- 11.4 years) with AA. The SFFECG was recorded with a pacemaker sized four electrode array acutely placed in the pacemaker pocket during implantation. The signals were analyzed to obtain peak-to-peak R wave amplitude and R to R interval variability (indicative of AAs). RESULTS: In sixteen patients R waves were visually discernible in all recordings. The percentage over and under detection for automatic R wave recognition SFFECG was 3 and 9%, respectively. R to R variability analysis using the SFFECG produced results concordant to those using the surface ECG. CONCLUSION: SFFECG might be a helpful adjunct in implantable device systems for detection of R waves and may be used for measurement of R to R variability.

Aged↗
PubMed2001

Heterogeneous tissue distribution of a mitochondrial DNA polymorphism in heteroplasmic subjects without mitochondrial disorders.

CONTEXT: Several maternally inherited point mutations of the mitochondrial genome cause mitochondrial disorders, but the correlation between genotype and phenotype remains obscure in many cases. The same mutation may cause various diseases, probably because of a different tissue distribution. OBJECTIVE: To assess the role of random somatic segregation in generating interperson differences by analysis of an apparently neutral polymorphism. DESIGN: Screening of 81 brain samples from subjects without mitochondrial disorders and selection of five necropsy cases showing a high level of heteroplasmy for the polymorphism. MAIN OUTCOME MEASURES: A proportion of various distinct genotypes in the mtDNA pool of the tissues, identified by fluorescent PCR products, representing a short polycytosine tract of variable length in the mitochondrial displacement loop. RESULTS: Differences were found between organs or groups of organs within subjects, pointing towards somatic segregation of mtDNA. In addition, marked differences of this organ distribution occurred between subjects, which cannot be explained by tissue specific selection. CONCLUSIONS: The observed interperson differences can be explained by somatic segregation, which occurs randomly at various developmental stages. Besides tissue specific selection, this process might participate in the distribution of pathogenic mtDNA mutations.

Adolescent↗
PubMed2001

Selective reduction of bone blood flow by short-term treatment with high-dose methylprednisolone. An experimental study in pigs.

Treatment with corticosteroids is a risk factor for non-traumatic avascular necrosis of the femoral head, but the pathological mechanism is poorly understood. Short-term treatment with high doses of methylprednisolone is used in severe neurotrauma and after kidney and heart transplantation. We investigated the effect of such treatment on the pattern of perfusion of the femoral head and of bone in general in the pig. We allocated 15 immature pigs to treatment with high-dose methylprednisolone (20 mg/kg per day intramuscularly for three days, followed by 10 mg/kg intramuscularly for a further 11 days) and 15 to a control group. Perfusion of the systematically subdivided femoral head, proximal femur, acetabulum, humerus, and soft tissues was determined by the microsphere technique. Blood flow in bone was severely reduced in the steroid-treated group. The reduction of flow affected all the segments and the entire epiphysis of the femoral head. No changes in flow were found in non-osseous tissue. Short-term treatment with high-dose methylprednisolone causes reduction of osseous blood flow which may be the pathogenetic factor in the early stage of steroid-induced osteonecrosis.

Acetabulum↗
PubMed2001

[Clinical features and guidelines of treatment of mucosa-associated lymphoid tissue lymphoma of stomach]

The mucosa-associated lymphoid tissue (MALT) lymphoma is a very indolent disease. Its most common site is the stomach. The lymphoma begins as a reactive lymphocyte accumulation mostly due to an infection of Helicobacter pylori (HP). Through repeated mutations this tissue is transformed into the characteristic MALT lymphoma. At the time of the diagnosis the lymphoma is usually localised, but in one third of the patients the disease has already been disseminated. There are not any commonly accepted guidelines of therapy concerning this primary gastric MALT lymphoma, but certain general tendencies have already been defined. In the early disease the aim of the treatment is curative with the preservation of the stomach as much as possible. In a considerable number of cases, when the surface of the stomach is affected by HP, one can achieve histological and molecular biologic remission after eliminating the bacteria. However, there is no such therapeutic consequence to be expected in case of a deeply invasive tumour. The optimal treatment of patients of this group as well as those whose disease is resistant to HP eradication treatment together with those who are HP negative is radiotherapy or surgery with chemotherapy. In this latter case quality of life becomes worse. In an advanced case cure is impossible and chemotherapy is the most effective to ease the patient's state.

Journal Article↗
PubMed2001

JMM, past and present. Cysticerci cellulosae of the brain. 1864.

While striving to serve the needs of the international biomedical community of today, we would also like to remember JMM's long past as a venue for medical research. JMM is the successor to the Berlin Clinical Weekly (Berliner Klinische Wochenschrift), established in 1864. Below are excerpts from the Berlin Clinical Weekly's May issue from a hundred and thirty-five years ago, giving hints about the challenges and solutions being addressed by medical research of the time. Following the excerpt is a commentary by Martin Zeitz and Thomas Schneider, experts in gastroenterology at the University Clinic Benjamin Franklin in Berlin, Germany.

Animals↗