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Biomedical subjects

R Ullrich

Publications and source records attributed to R Ullrich.

At least 91 records · Page 5Linked to original sources
PubMed1996

[MR imaging in gout].

The appearance of gouty tophus in magnetic resonance imaging (MRI) is characteristic. On T1- and T2-weighted SE images, the signal intensity of tophaceous lesions is similar to that of muscles. According to the histology, T2-weighted SE images demonstrate extremely hyperintense signals, which reflect the high protein content in the amorphous center of the tophus. The microscopic urate crystals deposited there have no MRI signal and are of no further diagnostic impact. Vascularized granulation tissue surrounding the tophus center enhance after intervenous application of contrast agents (Gadolinium). The inflamed tophus is associated with local edema, causing high signal intensity. MRI is superior to plain radiography for early detection of intraosseous tophi. Involvement of anatomical structures such as ligaments and tendons can be evaluated sufficiently. For peripheral joints, axial slice orientation is most helpful.

Adult↗
PubMed1996

[Measuring amniochorionic membrane thickness with high frequency ultrasound].

The postpartal thickness of the amniochorionic membrane was measured by means of 20 MHz ultrasound after 28 inconspicuous deliveries in the course of a prospective study. The aim of our investigation was to determine the thickness of the amniochorionic membrane using high frequency ultrasound and to evaluate the results for a statistical correlation with fetal and maternal parameters. The data obtained were compared with histological sections for measurement accuracy using a linear regression analysis method. Membrane thickness of the total study group was 0.83 +/- 0.11 mm (0.72-1.08 mm). Based on a statistical comparison with the histological sections, the high frequency ultrasonographic examination was shown to be highly reliable with a correlation coefficient of r = 0.96 (p < 0.0001). Results obtained by ultrasonography were correlated with maternal (gestational age, patient age, parity) and neonatal (size and weight at birth, sex, placental weight, Apgar 1/5/10) parameters by means of linear regression analysis. There was a statistically significant correlation between parity and membrane thickness (r = 0.485, p < 0.05). There was also a correlation of Apgar scores at 5 minutes post partum (r = 0.485, p < 0.05). We were able to demonstrate that the measurement of membrane thickness by ultrasound is an objective and reliable method and may be a gain to prenatal diagnostics when used in vivo.

Adolescent↗
PubMed1996

Stool viruses, coinfections, and diarrhea in HIV-infected patients. Berlin Diarrhea/Wasting Syndrome Study Group.

To examine the prevalence of stool viruses and their role in the pathogenesis of diarrhea in HIV infection, we evaluated biopsies and repeated stool samples of 256 HIV-infected patients undergoing diagnostic endoscopy because of diarrhea (n = 136) or other symptoms (n = 120) for bacterial, protozoal, and viral enteropathogens. In 70% of the patients with diarrhea, at least one potential enteropathogen was detected. Stool virus was detected by electron microscopy in 17% (44 of 256), adenovirus in 6.6% (17 of 256), and coronavirus in 11.3% (29 of 256) of the patients. Adenovirus and coronavirus were detected more frequently in patients with diarrhea than in patients without diarrhea [adenovirus 10% (13 of 136) vs. 3.3% (4 of 120), p = 0.0129; coronavirus 15% (21 of 136) vs. 6.6% (8 of 120), p = 0.0142]. Sixty-one percent of patients harboring stool virus were coinfected by another enteropathogen. Pathogens other than stool virus were detected more frequently in patients harboring adenovirus (82%) than in patients without stool virus (48%, p < 0.025). Adenovirus and coronavirus are frequently detected in stools of HIV- infected patients and may contribute to diarrhea. Adenovirus infection may facilitate the occurrence of other intestinal pathogens. Due to frequent coinfections, detection of stool viruses reduces the rate of diarrhea of unknown origin only by approximately 5%.

Acquired Immunodeficiency Syndrome↗
PubMed1996

Immunological and trophical effects of Saccharomyces boulardii on the small intestine in healthy human volunteers.

Saccharomyces boulardii (S.b.) is used for the prevention and treatment of diarrhea of different etiologies. We prospectively investigated the effects of S.b. on lymphocytes and duodenal mucosa. Before and after oral administration of S.b. for 3 weeks, circulating and intestinal lymphocytes were isolated and characterized by flow cytometry. Trophic effects on duodenal mucosa were investigated by morphometry and determination of brush border enzyme activity. Results were compared intraindividually before and after S.b. In intestinal lymphocytes no phenotypic changes were observed. CD4+ cells of the peripheral blood had a significantly increased expression of CD25 (p < 0.02). None of twelve volunteers had an increase in villous surface area (n.s.). Immunoglobulin A content in small intestine secretion was unaltered. An increase in brush border enzyme activity of lactase, alpha-glucosidase, and alkaline phosphatase was observed (p < 0.01). Our findings indicate that S.b. has a positive effect on the maturation of enterocytes and only a minor influence on lymphocytes.

Administration, Oral↗
PubMed1996

The immunologic aspects of human immunodeficiency virus infection in the gastrointestinal tract.

The intestinal (in particular rectal) mucosa is an important portal of entry of human immunodeficiency virus (HIV) in homosexual men, who represent the vast majority of HIV-infected patients in Europe and North America. There are several possibilities for HIV to reach the CD4+ T cells, macrophages, and follicular dendritic cells in the intestinal mucosa. HIV may be transported through M cells directly to mucosal lymphoid follicles. Alternatively, HIV may infect enterocytes via Fc-receptor by antibody-bound HIV or via a CD4 independent receptor. By successive budding on the basal side of enterocytes, HIV may be released into the lamina propria. Furthermore, in patients not infected by the intestinal route, HIV may also rapidly enter the intestinal mucosa by other mechanisms: intestinal T-lymphocytes are mainly activated memory T cells reentering the mucosal surfaces after circulating through the peripheral blood. In the periphery they may have been preferentially infected by HIV. Accumulation of infected T cells could thus occur in the intestinal mucosa. The special phenotypical and functional characteristics of intestinal T lymphocytes may affect the replication and cytopathicity of HIV, resulting in an accelerated loss of CD4 positive T cells in the lamina propria. CD4 T cells play a critical role in antigen-dependent B cell differentiation, thus the pronounced CD4 T cell depletion in the intestinal mucosa may be responsible for the observed decrease of IgA plasma cells and a reduced secretion of IgA2. Depletion and functional impairment of activated mucosal lamina propria lymphocytes by HIV infection could explain the break-down of the mucosal immune barrier leading to secondary opportunistic or nonopportunistic infections and secondary malignancies. In addition, because of the interrelation between the mucosal immune system and the epithelium these changes might be responsible for the partial small intestinal mucosal atrophy and maturational defects in enterocytes observed in HIV-infected patients. To be effective, a future prophylactic vaccine against HIV has to be able to induce not only systemic but also a local mucosal cellular and humoral protective immune response.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Interaction of the A alpha Y and Z mating-type homeodomain proteins of Schizophyllum commune detected by the two-hybrid system.

The A alpha locus is one of four mating-type loci that control sexual development in Schizophyllum commune. A alpha has nine alternative mating types (A alpha 1-A alpha 9) which encode specific alleles of two homeodomain-related proteins, Y and Z. For example, proteins Y4 and Z4 are encoded by A alpha 4, and Y5 and Z5 are encoded by A alpha 5. Our previous studies showed that A alpha-regulated development is activated in fusion cells between haploid strains by the presence of Y and Z proteins derived from different A alpha mating types (e.g., Y4 and Z5), but not by proteins from the same mating type (e.g., Y4 and Z4). In this study we analyzed protein-protein interactions of Y4 with the Z4 and Z5 isoforms in a two-hybrid system. Protein interactions were detected in filter and liquid assays for beta-galactosidase with Y4 and Z5, a non-self, developmentally active combination, but not with Y4 and Z4, a self, developmentally inactive combination. These results support the hypothesis that non-self combinations of Y and Z form a heteromultimer that activates development, but that self combinations do not. Although developmental target genes directly regulated by the A alpha locus have yet to be identified, it is assumed on the basis of motifs encoded that the Y-Z heteromultimer acts as a transcription factor.

Base Sequence↗
PubMed1995

[Superimposed high-frequency jet ventilation (SHFJV) in the administration of NO. Technical basis and early clinical results with ARDS].

The mortality of patients with acute respiratory distress syndrome (ARDS) is still above 50% despite continuous progress in intensive care medicine. Recent therapy regimens such as the extra corporeal life support (ECLS), permissive hypercarbia, high-frequency ventilation techniques and inhaled nitric oxide (NO) are being applied. All of the above techniques are aimed at different parts of the problems caused by ARDS. This study was designed to evaluate the possible additive benefits of superimposed high-frequency jet ventilation (SHFJV) and inhaled NO. METHODS. In experiments on a lung simulator it was demonstrated that it is possible to administer exact amounts of NO using a computer-controlled system with a feedback loop (Pulmonox) using the SHFJV. Applying the therapeutic reference point of 20 ppm of NO, the deviation was +/- 3 ppm at this setting. CASE REPORT. After successfully concluding our experiments, this combined therapy concept was applied in a patient with terminal ARDS. Under CMV, paO2 was 69.4 mm Hg and the oxygen saturation 88.3% with a F1O2 of 1.0. Significant improvement was observed within 30 min after starting SHFJV with inhaled NO (paO2 282.9 mm Hg; oxygen saturation 99.5%). There were no differences observed in hemodynamic parameters between CMV and SHFJV. Although the pulmonary status of the patient improved, the patient died due to therapy-resistant hemodynamic failure. CONCLUSION. It will take further studies to judge whether the success of this new ventilation strategy is reproducible and if the improvement of the oxygenation is more pronounced when adding inhaled NO to SHFJV than when each technique is applied separately.

Anesthetics, Inhalation↗
PubMed1995

Compliance mismatch and formation of distal anastomotic intimal hyperplasia in externally stiffened and lumen-adapted venous grafts.

OBJECTIVE: Compliance and formation of distal anastomotic intimal hyperplasia (DAIH) were investigated in externally stiffened venous grafts of varying calibers. METHODS: 36 femoropopliteal reconstructions were performed in 18 sheep. The autologous venous grafts were inserted into tubes made of Dacron mesh to achieve compliance-mismatch and lumen adaptation. Compliance was measured by echotracked ultrasonography and profiles of DAIH were generated from histologic sections harvested after 8.3 months. MAIN RESULTS: The external mesh tube significantly lowered the local compliance of graft and host artery. DAIH appeared extensively in those groups where mesh tube constricted venous grafts met untreated host arteries (p = 0.002). No differences in compliance and DAIH formation were observed when grafts with large and adapted diameters were compared. CONCLUSIONS: For prevention of DAIH the distal venous graft diameter is not important, while the local compliance of an autologous vein is a predictive factor for DAIH formation and thus long-term patency.

Anastomosis, Surgical↗
PubMed1995

Culture of intestinal biopsy specimens and stool culture for detection of bacterial enteropathogens in patients infected with human immunodeficiency virus. The Berlin Diarrhea/Wasting Syndrome Study Group.

The diagnostic yields of stool cultures and biopsy specimens for the detection of enteric bacterial pathogens in 213 human immunodeficiency virus-infected patients were compared. Forty-five percent (19 of 42) of the pathogens were detected exclusively by stool culture, 2% (1 of 42) of the isolates were detected exclusively by culture of biopsy specimens, and 53% (22 of 42) were detected by both methods. Repeated stool cultures remain the most important means of diagnosing enteric bacterial pathogens, which were encountered in 20% (40 of 213) of all patients. The additional culture of biopsy specimens should be reserved for patients with suspected mycobacteriosis.

AIDS-Related Opportunistic Infections↗
PubMed1995

Loss of CD4 T lymphocytes in patients infected with human immunodeficiency virus type 1 is more pronounced in the duodenal mucosa than in the peripheral blood. Berlin Diarrhea/Wasting Syndrome Study Group.

Although changes in T lymphocyte subset distribution in the peripheral blood of patients infected with human immunodeficiency virus (HIV) are well defined it is not known whether these changes reflect changes in lymphoid compartments clearly involved in HIV related disease like the intestinal mucosa. This study analysed lymphocytes isolated simultaneously from the peripheral blood and duodenal biopsy specimens by three colour flow cytometry in eight asymptomatic HIV infected patients, 26 AIDS patients, and 23 controls. The proportion of CD4, CD8, CD4-CD8-, or gamma delta T cells did not correlate between circulating and duodenal T cells. CD4 T cells were reduced in the peripheral blood (7.5% (25th-75th percentile, 2-16%) v 52% (41-63%), p < 0.0005) and even more reduced in the duodenum (1% (1-2%) v 36% (23-57%), p < 0.0005) of AIDS patients compared with controls. Patients with asymptomatic HIV infection had intermediate CD4 T cells in the peripheral blood (24% (22-35%); p < 0.002 v controls; p < 0.01 v AIDS) but like AIDS patients very low CD4 T cells in the duodenum (3% (1-6%); p < 0.002 v controls). The ratio of duodenal to circulating CD4+ T cells was significantly reduced to 0.2 (0-1) in AIDS patients (p < 0.001) and even to 0.1 (0.04-0.5) in asymptomatic HIV infected patients (p < 0.002) compared with 0.72 (0.44-0.95) in controls. These findings show an early and preferential loss of duodenal CD4 T cells in HIV infection. Immunological abnormalities in HIV infection are distinct between lymphoid compartments, and profound immunodeficiency may occur in the intestinal immune system although circulating T cells are largely preserved.

Acquired Immunodeficiency Syndrome↗
PubMed1995

[Lyme borreliosis and cardiomyopathy].

According to current opinion there is acute, self-limiting Lyme carditis, and chronic Lyme carditis. Acute Lyme carditis manifests mostly as transient conduction disorders of the heart (e.g. AV-blocking I to III), and as supraventricular and ventricular rhythm disturbances, pericarditis, myocarditis, and pancarditis in single cases. Chronic Lyme carditis is defined as a case of chronic heart failure confirmed by positive serology and endomyocardial biopsy. Anamnestic aid is rare. Neither tick-bites nor preceding or accompanying erythema chronicum migrans are constantly reported. Seropositivity and control of its specificity by western blot are indicative but no etiological proof. Even histological detection of spirochetes in endomyocardial tissue or cultivation of borrelia from endomyocardial biopsy are no final etiological proof of the respective cardial disorder. Those findings, however, are an indication for antibiotic treatment. According to the severity of the disorder, antibiotics are administered orally (penicillin or derivatives) or parenterally with penicillin or cephalosporins of the 3rd generation over 4 and 2 weeks, respectively.

Antibodies, Bacterial↗