[Illness and immune manifestations in Whipple disease. Differential rheumatic diseases diagnosis].
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Publications and source records attributed to T Schneider.
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The SIV infection of rhesus macaques (Macaca mulatta) is the most appropriate animal model in HIV research. The permanent human T-cell line C8166 is used for in vitro SIV propagation. This paper describes ultrastructural features of the cells after infection with SIVmac. The C8166 cells are ultrastructurally characterized by a heterogenous morphology which is independent of the infection. SIV induced cell syncytia are observed 18 hours after infection. Viral particles and budding occur 48 hours p.i with a peak at the day 8. Viral particles present the typical lentiviral morphology. Using the monoclonal antibody anti SIVp28 and ultra small (0.8 nm) immunogold-silver enhancement technique, we are able to demonstrate SIV antigen immunoelectron microscopically. Therefore, this ultrastructural method is suitable to detect SIV antigen in in vivo experiments with C8166 cells from day 8 p.i. serving as positive control.
OBJECTIVE: To examine the potential of gadolinium (Gd)-enhanced dynamic MRI in the detection of early femoral head ischemia. Furthermore, to apply a three-compartment model to achieve a clinically applicable MR index for femoral head perfusion during the steady state and arterial hip joint tamponade. DESIGN AND MATERIALS: In a porcine model femoral head perfusion was measured by radioactive tracer microspheres and by using a dynamic Gd-enhanced MRI protocol. Femoral head perfusion measurements and MRI tests were performed unilaterally before, during and after the experimentally induced ischemia of one of the hip joints. Ischemia was induced by increasing intra-articular pressure to 250 mmHg. RESULTS: All pigs showed ischemia of the femoral head epiphysis under hip joint tamponade followed by reperfusion to the same level as before joint tamponade. In two cases perfusion after removal of tamponade continued to be low. In dynamic MRI measurements increases in signal intensity were seen after intravenous infusion of Gd-DTPA, followed by a slow decrease in signal intensity. The signal-intensity curve during femoral head ischemia had a minor increase. Also the coefficient determined was a helpful indicator of femoral head ischemia. CONCLUSIONS: Femoral head blood flow as measured by microspheres fell significantly under joint tamponade. Early detection of this disturbed regional blood flow was possible using a dynamic MRI procedure. A biomathematical model resulted from the evaluation of the intervals of signal intensity over time which allows detection of bone blood flow changes at a very early stage. Using this new method earlier detection of femoral head necrosis may be possible.
OBJECTIVE: This study was undertaken to evaluate whether sonography is a useful tool in the diagnosis of soft tissue disorders as a possible cause for discomfort and/or pain after shoulder arthroplasty. DESIGN AND PATIENTS: Static and dynamic ultrasound examinations were performed in the standard sectional planes on 22 patients with 25 hemiprostheses and the results were correlated with the clinical outcome. The stability was determined in the transverse and frontal planes and the clinical results were evaluated according to the Constant and Swanson scores. RESULTS: Several pathological changes were detected: rotator cuff lesions, subdeltoid bursitis, changes around the long biceps tendon as well as an increase in intra-articular volume due to effusion and/or synovitis. The correlation of sonographic and clinical results demonstrated that patients with an excellent clinical result showed no or only a few pathological findings on sonography compared with those with a moderate or poor result. CONCLUSION: Pathological changes of the periarticular tissue in the direct neighbourhood of the implant can be detected by sonography, which can be recommended as a valuable examination technique to evaluate the soft tissue in patients after shoulder arthroplasty.
To develop new therapeutic strategies we examined the expression and signaltransduction of G protein-coupled receptors in a human transitional cell carcinoma cell line. The receptors for lysophosphatidic acid (LPA) and thrombin potently stimulate cell migration. Pretreatment with PTX completely inhibited cell motility induced by LPA. In the model of chemically induced bladder carcinoma in rats the effects of intravesical instillation of PTX or phosphate buffered saline was examined. The incidence of G2-G3 cells in cytology was significantly reduced in rats treated with PTX. To ascertain the side effects of intravesical instillation of PTX a Phase I study was initiated. 15 patients were instilled with PTX at 5 dose levels (14-72 micrograms/100 ml) 3 times a week. Instillation of PTX up to 72 micrograms was without local or systemic side effects. PTX is a substance which potently inhibits tumor cell motility and progression. Intravesical treatment was well tolerated and therefore, the influence of PTX on local tumor should be evaluated in a Phase II study.
The removal of well-fixed or porous-coated cementless stems is demanding and associated with a hig perioperative risk to the patient. Only a few surgical techniques have been published about this procedure. We introduce a special, ballistically driven, flexible chisel for the disruption of bone ingrowth or fibrous encapsulation. In six cases the stem removal was successful after 8-15 min (average 12,2 min) without damage to the bone. Reimplantation is possible with standard stems for primary surgery. This surgical technique leads to a predictable procedure, reduces the risk for the patient, the operation time and costs. We are continuing with this technique under supervision by the local Ethics Commission.
The role of endothelin-1 (ET-1) in certain pathological states is still unclear. We have investigated the effect of anthracyclines (maximum dose, 450 mg/m(2) of body surface) on left ventricular systolic and diastolic function and how it influences the level of plasma ET-1 in 21 patients (12 female and nine male) with Hodgkin and non-Hodgkin lymphoma. We also studied the association between plasma ET-1 concentration and echocardiographic parameters. Serum ET-1 was measured by ELISA. Left ventricular function was analysed by echocardiography: ejection fraction (EF), velocity-time integral, E- and A-waves, E:A ratio, deceleration time (DT) and Doppler index were all measured. Statistical analysis was made by the Wilcoxon rank test. EF and serum ET-1 level decreased significantly (EF, 56.29+/-5.0% to 48.57+/-5.9%, P<0.0001; ET-1, 6.45+/-4.0 pg/ml to 2.9+/-1.0 pg/ml, P<0.0001). DT increased significantly (179.8+/-47.8 ms to 215.5+/-66.7 ms, P<0.01) after anthracycline therapy. There was no difference in other echocardiographic parameters before and after therapy. The decrease in serum ET-1 concentration might be a result of anthracycline's direct cytotoxic effect and the decreasing level of ET-1 can play a role in the reduction of EF. However, more studies are needed to evaluate the presence and severity of endothelial damage.
BACKGROUND AND STUDY AIMS: Endoscopic ductal decompression therapy has become an established method of treating patients with painful obstructive chronic pancreatitis. Smaller series, mostly with a medium-term follow-up period, have reported encouraging results. The present analysis presents long-term follow-up data from a large multicenter patient cohort. PATIENTS AND METHODS: Patients with painful chronic pancreatitis and with ductal obstruction due to either strictures and/or stones treated endoscopically at eight different centers underwent follow-up after 2 - 12 years (mean 4.9 years). The patients' clinical data, the rate of technical success, and complications were recorded from the charts. Follow-up data were prospectively obtained using structured questionnaires; the main parameter for evaluating treatment success was a significant reduction in pain (no pain or only weak pain). RESULTS: Follow-up data were obtained from 1018 of 1211 patients treated (84%) with mainly strictures (47%), stones (18%), or strictures plus stones (32%). At the long-term follow-up, 60% of the patients had their endotherapy completed, 16% were still receiving some form of endoscopic treatment, and 24% had undergone surgery. The long-term success of endotherapy was 86% in the entire group, but only 65% in an intention-to-treat analysis. There were no significant differences between the patient groups with regard to either strictures, stones, or both. Pancreatic function was not positively affected by endoscopic therapy. CONCLUSIONS: Endoscopic ductal decompression therapy offers relief of pain in two-thirds of the patients when it is used as the only form of treatment. One-quarter of the patients have to undergo surgery.
The particle size-dependent sampling velocity of the passive dust sampler developed by Vinzents (1996) is investigated under field conditions. Microscopical determination of the projected area equivalent diameter is used to quantify particles deposited on the sampler foils. Parameters for a semi-empirical model for particle deposition velocities on upward and forward facing foils are fitted to the data and it is shown that deposition mechanisms other than gravitational settling on the upward facing foil can be neglected. For calculation of airborne mass concentration no information on particle density is needed and only the ratio between the dynamic and volume shape factors needs to be known. Given the sampling velocity, the airborne mass per diameter interval is calculated from samples obtained in the wood industry, from which inhalable dust concentrations are calculated. The results are in line with parallel samples obtained with an inhalable dust sampler. A 'total' dust sampling characteristic can be fitted which reproduces measured 'total' dust with a closed face monitor. The results of this study demonstrate the validity of the passive dust sampling principle in environments involving even large (>100 microm) particles and the potential to predict the concentration of several size fractions.
BACKGROUND: Little is known about secretory immunity-the major defence mechanism at mucosal surfaces-in human immunodeficiency virus (HIV) infected patients, especially in the early stages of the disease. AIMS: The aim of the study was to analyse mucosal immunoglobulin production and simian immunodeficiency virus (SIV) specific antibody response in the intestinal mucosa during the course of SIV infection in comparison with serum and saliva. ANIMALS AND METHODS: IgG, IgA, and IgM concentrations were determined in supernatants of short term cultured duodenal biopsies, serum, and saliva from SIV infected rhesus macaques (n=8) and controls (n=2) by ELISA at defined times before and after infection. Specific antibodies to SIV were detected by western blot and/or dot blot analysis. In addition, rectal swabs from two uninfected and 12 SIV infected rhesus macaques (seven without and five with enteritis) were analysed for albumin and IgG concentrations. RESULTS: An increase in total intestinal IgG and a decrease in IgA were observed. SIV specific IgG or IgA responses were detectable as early as one week after SIV infection in the serum of seven of eight animals. In contrast, intestinal SIV specific IgG production was detected only four weeks after infection in six of eight animals, and intestinal SIV specific IgA was not produced in the intestine at any time point. In saliva, the secretory component on SIV specific IgA was only detected in one animal at week 24 after infection. Enteritis is frequent in SIV infected animals and results in a significant increase in albumin and IgG secretion into the intestinal lumen. CONCLUSION: Despite modest quantitative changes in mucosal immunglobulin production there was a total lack of SIV specific IgA synthesis in the intestine during SIV infection. This lack or disturbed secretory SIV specific IgA response at mucosal surfaces may explain the rapid and high HIV/SIV replication in this compartment. In addition, our investigations indicate secretion of serum proteins into intestinal fluids during SIV infection. Previous investigations using intestinal secretions or swabs for analysing quantitative and specific immunglobulins therefore should be interpreted with caution.
White (WAT) and brown (BAT) adipose tissue are tissues of energy storage and energy dissipation, respectively. Experimental evidence suggests that brown and white preadipocytes are differentially determined, but so far not much is known about the genetic control of this determination process. The aim of this study was to identify differentially expressed genes involved in brown and white preadipocyte development. Using representational difference analysis (cDNA RDA) and DNA microarray screening, we identified four genes with higher expression in white preadipocytes (three different complement factors and delta-6 fatty acid desaturase) and seven genes with higher expression levels in brown preadipocytes, of which three are structural genes implicated in cell adhesion and cytoskeleton organization (fibronectin, alpha-actinin-4, metargidin) and four that might function in gene transcription and protein synthesis (vigilin, necdin, snRNP polypeptide A, and a homolog to human hepatocellular carcinoma-associated protein). The expression profile of these genes was analyzed during preadipocyte differentiation, upon beta-adrenergic stimulation, and in WAT and BAT tissue in vivo compared with references genes such as peroxisome proliferator-activated receptor-gamma (PPARgamma), uncoupling protein 1 (UCP1), cytochrome c oxidase.
In an earlier study, we showed that heteroplasmy in the mitochondrial genome of gliomas sometimes occurs in a D-loop polycytosine tract. We extended this study by pairwise comparisons between glioma samples and adjacent brain tissue of 55 patients (50 glioblastomas, 1 astrocytoma WHO grade III, 4 astrocytomas WHO grade II). We used a combination of laser microdissection and PCR to detect and quantify variations in the polycytosine tract. New length variants undetectable in the adjacent brain tissue were observed in 5 glioblastomas (9%). In 2 of these cases, samples from a lower tumor stage (WHO grade II) could be analyzed and revealed the early occurrence of these mutations in both cases. Since the mitochondrial D-loop contains additional repeats and highly polymorphic non-coding sequences, we compared 17 glioblastomas with the corresponding blood samples of the same patients by direct sequencing of the complete D-loop. In 6 of these tumors (35%), instability was detected in 1 or 2 of 3 repeat regions; in 1 of these repeats, the instability was linked to a germline T-to-C transition. Furthermore, of 2 tumors (12%) 1 carried 1 and the other 9 additional transitions. In the latter patient, 6.7 kb of the protein coding mtDNA sequence were analyzed. Six silent transitions and 2 missense mutations (transitions) were found. All base substitutions appeared to be homoplasmic upon sequencing, and 89% occurred at known polymorphic sites in humans. Our data suggest that the same mechanisms that generate inherited mtDNA polymorphisms are strongly enhanced in gliomas and produce somatic mutations.
Infection of humans with Helicobacter pylori results in the development of chronic gastritis and plays an important role in gastric ulcer pathogenesis. Despite the infiltration of the mucosa with specific immunocompetent cells and production of specific antibodies, the infection usually persists for life. This study was performed to investigate if immunologic mechanisms exist which could contribute to the inability of the host to terminate the infection. Therefore, we compared the in vitro immunoreactivity of peripheral blood mononuclear cells (PBMC) from H. pylori-infected patients after stimulation with sonicated H. pylori bacteria from the stomach of the patient (autologous bacterial strain) with stimulation by bacteria from other patients (heterologous bacteria). We measured cell proliferation, expression of T cell activation markers CD25, HLA-DR, and CD71, as well as production ofinterleukin-10 (IL-10), an inhibitory cytokine. We found that the proliferative response of PBMC was significantly lower after autologous than after heterologous stimulation. Furthermore, secretion of IL-10 in the culture supernatants was significantly higher when PBMC were incubated with autologous than with heterologous H. pylori antigens. No significant differences between autologous or heterologous stimulation were observed in the increased expression of T cell activation markers. These data indicate that systemic immunologic response to H. pylori are strain-dependent. For further studies of the immune responses towards H. pylori, the use of an autologous stimulatory system seems necessary.
We show that the unusual doping dependence of the isotope effects on transition temperature and zero temperature in-plane penetration depth naturally follows from the doping driven 3D-2D crossover and the 2D quantum superconductor to insulator transition in the underdoped limit. Since lattice distortions are the primary consequence of isotope substitution, our analysis clearly reveals the strong involvement of lattice degrees of freedom in mediating superconductivity.
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A new approach for the synthesis of gamma-alkylidenetetronic acids and esters is reported which involves Me3SiOTf-catalyzed, regio- and stereoselective cyclization of 4-alkoxy-1,3-bis(trimethylsilyloxy)-1,3-butadienes with oxalyl chloride. The alpha-hydroxy group of the butenolides is efficiently functionalized by palladium-catalyzed cross-coupling reactions via the corresponding enol triflates.
HISTORY AND ADMISSION FINDINGS: A 16-year-old man experienced fatigue, vomiting and diffuse abdominal pain. Since 4 days he had myalgia in both arms and legs. On examination only a tachycardia of 110/min was noticed. INVESTIGATIONS: Laboratory tests revealed hemoglobin 12.7 g/dl, leucocytes 10,300/microliter, platelets 89,000/microliter, LDH 191 U/l, sodium 134 mmol/l, potassium 2.76 mmol/l, calcium 4.52 mmol/l (I), creatinine 1.13 mg/dl, urea 72 mg/dl, uric acid 11.2 mg/dl. The levels of PTH (0 pg/ml), PTH-related peptide, vitamin D, vitamin A, IGF-1, STH, 5-HIES and interleukin 6 were within normal limits. TNF-alpha 25.9 pg/ml (< 8.1). The electrocardiography revealed a sinus rythm with a QT-time of 0.28 s (= 100%). Multiple osteolytic bone leasions were seen in thoracic CT-scan. Abdominal sonography showed normal liver structure, multiple subhepatic lymph nodes without splenomegaly. The cytologic examination of the bone marrow demonstrated a diffuse infiltration by a common acute leukemia. TREATMENT AND COURSE: The rehydration with physiologic saline (3500 ml/d) was initiated in the ICU. Furosemide was added for further renal excretion. Additionally prednisone (100 mg/d) and calcitonin (300 I.E./d) were given. The calcium level fell within two days. No cardiac arrhythmia nor acute renal failure were seen. After definitive diagnosing the patient was treated corresponding to a specific protocol. One year later the relapsing ALL was diagnosed also by hypercalcemia (5.9 mmol/l). The level of TNF-alpha before and after correction of hypercalcemia was 20 pg/ml. CONCLUSION: The acute treatment of hypercalcemia is independent of the underlying cause (rehydration with physiologic saline, renal excretion with furosemide, inhibition of osteoclastic activity). The main causes are hyperparathyreoidism or malignancys (90%). We describe TNF-alpha as a possible marker of tumoral load of a common ALL but we are not able to reveal a correlation between TNF-alpha and the calcium level.