Search PubMed⌕ Search

Biomedical subjects

E Fischer

Publications and source records attributed to E Fischer.

At least 19 recordsLinked to original sources

Active immunisation during an outbreak of hepatitis A in a German day-care centre.

During an outbreak in a German day-care centre (DCC) caring for 100 children HAV vaccination was recommended for children, employees and household members of cases. A retrospective cohort study was done to evaluate vaccine uptake and identify possible risk factors for disease. Between 19 December 2004 and 30 January 2005 eight DCC children and seven household members fulfilled the case definition, i.e. had clinical hepatitis (14) or were diagnosed with asymptomatic HAV infection (1). Following the recommendation to vaccinate, given on 23 December 2004, 66.7% (46/69) of DCC children, 15.8% (29/184) of household members and 5/5 of employees were vaccinated, and three vaccinated children and two not vaccinated children fell ill. One of 11 children who received human normal immunoglobulin (HNIG) and four of 58 children who did not receive HNIG fell ill. In households in which the DCC child received HAV vaccine and/or HNIG, seven (5.6%) of 125 household members fulfilled the case definition. In households of non-immunised children none of the 59 household members fell ill. We conclude that, although most vaccinations were administered promptly, they may not have been timely enough to impact the course of the outbreak.

Child↗

Effect of nectar secretion rate on pollination success of Passiflora coccinea (Passifloraceae) in the Central Amazon.

The pollination of Passiflora coccinea by the hummingbird Phaethornis superciliosus was studied in Central Amazon, Brazil. We hypothesized that a greater nectar secretion rate (NSR) increases the pollination success of single flowers through Ph. superciliosus visiting behavior. For control flowers, NSR was an increasing function of flower base diameter (FBD). The total number of Ph. superciliosus probes per flower was an increasing function of FBD. Additionally, deposition of pollen on stigmas increased with the cumulative number of Ph. superciliosus probes. Our results show that larger P. coccinea flowers secrete nectar at higher rates, are probed more times during each hummingbird visit and are more successful at pollination. This seems to be the first non-manipulative study describing such an effect of NSR on the pollination of single flowers in nature.

Animals↗

The Linderniaceae and Gratiolaceae are further lineages distinct from the Scrophulariaceae (Lamiales).

The Lamiales are one of the largest orders of angiosperms, with about 22,000 species. The Scrophulariaceae, as one of their most important families, has recently been shown to be polyphyletic. As a consequence, this family was re-classified and several groups of former scrophulariaceous genera now belong to different families, such as the Calceolariaceae, Plantaginaceae, or Phrymaceae. In the present study, relationships of the genera Craterostigma, Lindernia and its allies, hitherto classified within the Scrophulariaceae, were analyzed. Sequences of the chloroplast trnK intron and the matK gene (approximately 2.5 kb) were generated for representatives of all major lineages of the Lamiales and the former Scrophulariaceae. Bayesian and parsimony analyses revealed two isolated lineages, one of which consists of Lindernia and its allies, the other of Gratiola and allies. Gratiola was previously assumed to be related to Lindernia and was therefore included here. It is proposed to treat the two clades as separate families, Linderniaceae and Gratiolaceae. For the Linderniaceae, several morphological synapomorphies exist in addition to molecular data, such as conspicuous club-shaped stamen appendages.

Bayes Theorem↗

[Resection of combined or sequential lung and liver metastases of colorectal cancer: indication for everyone?].

UNLABELLED: Successful sequential resection of isolated hepatic and pulmonary metastases of colorectal cancer (crc) has been reported, however long-term results of large series are lacking. Therefore, we retrospectively analysed data of patients in whom sequential hepatic and pulmonary resection for metastases was performed. PATIENTS AND METHOD: From the records of our hospital we identified 25 patients (19.5 % of all patients operated for hepatic or 33 % for lung metastases due to crc) with colorectal cancer who had pulmonary and hepatic resection for metastatic disease between 1991 and 2002. 11 of these had primary colonic cancer and 14 rectal cancer. None of the patients died perioperatively. Long-term results were correlated with the staging of the primary tumour, the number of metastases, disease free interval between primary tumour operation and occurrence of metastatic disease. RESULTS: Five-year survival rate was 33.5 % following the resection of the first metastasis. Three year survival after resection of the second metastasis was 39 %. The disease free interval was 20 months (mean). Long-term results were clearly influenced by the disease free interval: < 1 year (n = 6) median 50 months after resection of the crc; > 1 year median 90 months (n = 19). Further on R0 resection was important for long-term survival: Median survival was 32.5 (+/- 4.1) months following resection of the second metastasis but only 9.9 months after R > 0 resection. CONCLUSION: These results confirm that sequential resection of hepatic and pulmonary metastases can be performed with curative intention provided a systemic spread of the disease is excluded. The surgeon's opinion of resectability should be obtained in patients with such metastases before the patient is scheduled for palliative conservative treatment.

Aged↗

HLA-DRB1*04 and HLA-DQB1*03 association with the atrophic but not with the goitrous form of chronic autoimmune thyroiditis in a Brazilian population.

Autoimmune chronic lymphocytic thyroiditis appears in two forms, goitrous and atrophic. The evidence available is not enough to prove that the goitrous precedes the atrophic form, but immunogenetic analysis suggests that they may be distinct entities. The distribution of HLA class II alleles DRB1* and DQB1* was verified in patients from the region of Campinas, São Paulo, Brazil with both forms of thyroiditis. Ninety-one patients with primary hypothyroidism through autoimmune thyroiditis were classified as goitrous - 54 patients, 42.27 +/- 11.72 years old, having had hypothyroidism for 8.57 +/- 6.63 years - or atrophic - 37 patients, 42.72 +/- 12.01 years old, hypothyroidism for 6.73 +/- 4.07 years. The distribution of class II alleles was determined, DRB1* and DQB1* were genotyped after purifying DNA blood samples using the DNAzol technique, and the low-resolution PCR-SSP system was utilized for determination of generic alleles. Chi-square and Fisher's exact test were utilized to compare the distribution frequency of HLA alleles and the significant p-values were subjected to Bonferroni correction. We have demonstrated that the DRB1*04 allele is associated with autoimmune thyroiditis, and that there are genotypic differences regarding the presentation forms with a strong association between DRB1*04 and DQB1*03 and the atrophic form only.

Adolescent↗

Hand-assisted laparoscopic splenectomy for giant spleens.

BACKGROUND: Laparoscopic splenectomy for massive splenomegaly is technically difficult, and the morcellated splenic tissue may be inadequate for histologic study. A hand-assisted technique may provide a technical advantage and allow removal of larger pieces of spleen. METHODS: Patients who underwent hand-assisted laparoscopic splenectomy for massive splenomegaly were reviewed. Demographic information, operative data, and outcomes data were tabulated. RESULTS: Sixteen patients met these criteria. Mean age was 56 years (range, 35-78 years). Operating time averaged 240 min (range, 165-360 min), and median blood loss was 425 cc (range, 100-1800 cc). There were no conversions to an open procedure. Mean weight of extracted spleens was 2008 g (range, 543-4090 g). Postoperative length of stay averaged 3.3 days (range, 2-7 days). There was one postoperative complication (6.25%) and no mortality. CONCLUSIONS: Hand-assisted laparoscopic splenectomy for massive splenomegaly is feasible and safe while preserving the recovery benefits of minimal access surgery. It provides an adequate specimen for histologic study.

Adult↗

One-year survival and neurological outcome after pediatric cardiopulmonary resuscitation.

OBJECTIVE: Reported survival after cardiopulmonary resuscitation (CPR) in children varies considerably. We aimed to identify predictors of 1-year survival and to assess long-term neurological status after in- or outpatient CPR. DESIGN: Retrospective review of the medical records and prospective follow-up of CPR survivors. SETTING: Tertiary care pediatric university hospital. PATIENTS AND METHODS: During a 30-month period, 89 in- and outpatients received advanced CPR. Survivors of CPR were prospectively followed-up for 1 year. Neurological outcome was assessed by the Pediatric Cerebral Performance Category scale (PCPC). Variables predicting 1-year survival were identified by multivariable logistic regression analysis. INTERVENTIONS: None. RESULTS: Seventy-one of the 89 patients were successfully resuscitated. During subsequent hospitalization do-not-resuscitate orders were issued in 25 patients. At 1 year, 48 (54%) were alive, including two of the 25 patients with out-of-hospital CPR. All patients died, who required CPR after trauma or near drowning, when CPR began >10 min after arrest or with CPR duration >60 min. Prolonged CPR (21-60 min) was compatible with survival (five of 19). At 1 year, 77% of the survivors had the same PCPC score as prior to CPR. Predictors of survival were location of resuscitation, CPR during peri- or postoperative care, and duration of resuscitation. A clinical score (0-15 points) based on these three items yielded an area under the ROC of 0.93. CONCLUSIONS: Independent determinants of long-term survival of pediatric resuscitation are location of arrest, underlying cause, and duration of CPR. Long-term survivors have little or no change in neurological status.

Adolescent↗

Coronary artery bypass grafting supported with intracardiac microaxial pumps versus normothermic cardiopulmonary bypass: a prospective randomized trial.

OBJECTIVE: To analyze the difference in coronary artery bypass grafting (CABG) performed with normothermic cardiopulmonary bypass (CPB) and CABG supported with the intracardiac microaxial pump (ICP, Impella, Aachen, Germany). METHODS: A prospective randomized study was conducted in seven centers. The study population consists of 199 patients undergoing isolated primary CABG (CPB group 94 patients, ICP group 105 patients). Both groups are equal in demographic variables, number of bypasses performed, and Euroscore predicted mortality. We analyzed clinical outcome, myocardial enzymes and blood parameters of hemolysis, organ function and inflammatory response. RESULTS: Seventeen patients (16%), randomized in the ICP group, were switched to the CPB group. This was due to the inability to position the right side catheter adequately (n=8), to a pump failure (n=1) or to the perioperative decision that beating heart surgery is technically not possible (n=8). There was no significant difference between the two study arms regarding the pump assistance time (CPB 67.1+/-22.9 min; ICP 67.7+/-30.3 min; P=0.88861), the number of grafts (CPB 2.4+/-0.7; ICP 2.3+/-0.8) and the number of grafts to the back wall (CFX; both groups n=37). There is no significant difference in clinical outcome, evolution of myocardial enzymes, indices of organ function and hemolysis. There is a reduced inflammatory response in the ICP group as indicated in the postoperative release of granulocyte elastase (CPB 259+/-195; ICP 150+/-126 microg/l; P<0.00001) and complement C3 (CPB 0.73+/-0.2; ICP 0.65+/-0.2g/l; P=0.008). CONCLUSION: The intracardiac pump for the right heart is difficult to introduce. As a consequence the right side pump underwent design modifications. There were no differences in clinical outcome between both groups. The inflammatory response is significantly reduced in the ICP group.

Aged↗

Inhibition of fusion of Chlamydia trachomatis inclusions at 32 degrees C correlates with restricted export of IncA.

Chlamydia trachomatis is an obligate intracellular bacterium that develops within a parasitophorous vacuole termed an inclusion. The inclusion is nonfusogenic with lysosomes but intercepts lipids from a host cell exocytic pathway. Initiation of chlamydial development is concurrent with modification of the inclusion membrane by a set of C. trachomatis-encoded proteins collectively designated Incs. One of these Incs, IncA, is functionally associated with the homotypic fusion of inclusions. Inclusions also do not fuse when cultures are multiply infected with C. trachomatis and cultivated at 32 degrees C. We obtained evidence linking these experimental observations by characterizing IncA localization in 32 degrees C cultures. Analysis of inclusions by light and transmission electron microscopy confirmed that HeLa cells infected with multiple C. trachomatis elementary bodies and cultivated at 32 degrees C for 24 h contained multiple, independent inclusions. Reverse transcriptase PCR and immunoblot analyses of C. trachomatis-infected HeLa cells demonstrated the presence of IncA at 24 h in 32 degrees C cultures. When parallel cultures were probed with IncA-specific antibodies in indirect immunofluorescence assays, IncA was detectable in intracellular chlamydiae but not within the inclusion membrane. In addition, analysis of purified reticulate bodies from 37 and 32 degrees C cultures showed that bacterium-associated pools of IncA are enriched in cultures grown at 32 degrees C. Microscopic observation of infected cells revealed that some vacuoles had fused by 48 h postinfection, and this finding was correlated with the detection of IncA in inclusion membranes by immunofluorescence microscopy. The data are consistent with a requirement for IncA in fusions of C. trachomatis inclusions and suggest that the effect of incubation at 32 degrees C is manifested by restricted export of IncA to the inclusion membrane.

Bacterial Proteins↗

Pseudomembranous tracheobronchitis due to Bacillus cereus.

We present a case of a rapidly progressive pseudomembranous tracheobronchitis and pneumonia in a 52-year-old woman with severe aplastic anemia. Bacillus cereus was isolated from bronchoalveolar lavage fluids, blood cultures, and pseudomembrane biopsy specimens; despite intensive antibiotic treatment, the patient's condition deteriorated rapidly. To our knowledge, this is the first report of a B. cereus infection that has caused pseudomembranous tracheobronchitis, possibly because of the production of bacterial toxins.

Anti-Bacterial Agents↗

Localization of the chaperone domain of FKBP52.

FKBP52, a multidomain peptidyl prolyl cis/trans-isomerase (PPIase), is found in complex with the chaperone Hsp90 and the co-chaperone p23. It displays both PPIase and chaperone activity in vitro. To localize these two activities to specific regions of the protein, we created and analyzed a set of fragments of FKBP52. The PPIase activity toward both peptides and proteins is confined entirely to domain 1 (amino acids 1-148). The chaperone activity, however, resides in the C-terminal part of FKBP52, mainly in the region between amino acids 264 and 400 (domain 3). Interestingly, this domain also contains the tetratricopeptide repeats, which are responsible for the binding to C-terminal amino acids of Hsp90. Competition assays with a C-terminal Hsp90 peptide suggest that the non-native protein and Hsp90 are bound by different regions within this domain.

Animals↗

Shear banding and the isotropic-to-nematic transition in wormlike micelles.

Using deuterium NMR spectroscopy in a Couette cell, we observe shear-induced nematic ordering in the concentrated wormlike-micelle system CTAB/D(2)O, and our results are qualitatively consistent with birefringence studies, and in exact quantitative agreement with the degree of order measured in neutron-diffraction measurements. The width of the nematic region depends on shear rate, as well as on the temperature proximity to the equilibrium isotropic-nematic transition. Comparison of the nematic order profiles with velocity profiles obtained under identical conditions shows quite clearly that the nematic state is not identifiable with a highly sheared, low viscosity layer, and we conclude that the process of shearing induces a nematic state of high viscosity, possibly associated with mesoscale ordering. We present a simple model in which transition from the high shear branch to the viscous nematic branch is counterbalanced by subsequent relaxation of nematic order.

Biophysics↗

[Diagnostic approach prior to the onset of chronic renal insufficiency].

Chronic nephropathies are usually asymptomatic and should therefore be systematically depisted, especially in "high risk" patients. These subgroups of patients have been relatively well defined as subjects with hypertension, diabetes and ageing. A plasma creatinine concentration of 150 mumol/L can easily diagnose chronic renal failure with an absolute specificity (100% of the subjects do have a glomerular filtration rate beneath 80 mL/min). This threshold however is too high as some patients may already exhibit a significant reduction in renal function. "Corrected" creatinine, i.e., computing creatinine clearance using the Cockcroft's formula allows a more reliable estimation of glomerular filtration rate. The long term prognosis of chronic renal failure is far from good. The progression rate is higher in patients with persistent hypertension and heavy proteinuria that are themselves amenable to symptomatic therapies. Timely nephrologic referral is a warrant of optimal care.

Aged↗

Natural autoantibodies and complement promote the uptake of a self antigen, human thyroglobulin, by B cells and the proliferation of thyroglobulin-reactive CD4(+) T cells in healthy individuals.

Serum from normal individuals contains substantial amounts of natural antibodies (NA) capable of recognizing self antigens. However, the physiological implications of this autoreactivity remain unclear. We have examined the role of self-reactive NA and complement in mediating the uptake of human thyroglobulin (Tg) by human peripheral B cells in reconstituted whole blood. Significant binding of fluorescein isothiocyanate-conjugated-Tg to B cells was observed, and absorption of Tg-reactive antibodies from serum markedly reduced this uptake, as did inactivation of serum complement or blockade of complement receptor types 1 (CR1, CD35) and 2 (CR2, CD21). T cell responsiveness to Tg was examined in a preparation of peripheral blood mononuclear cells (PBMC) cultured in the presence of autologous serum. A subset of CD4(+) T cells exhibited a dose-dependent proliferative response to Tg, which was strongly inhibited by complement inactivation and by immunoabsorption of Tg-reactive antibodies. Furthermore, this T cell response was abrogated by depletion of B cells from the PBMC culture. These data imply that uptake of complement-opsonized Tg / anti-Tg complexes and subsequent presentation of Tg by B cells are prerequisites for the proliferation of Tg-reactive CD4(+) T cells, suggesting a novel role for natural autoantibodies and complement in the regulation of autoreactivity under physiological conditions.

Antigen Presentation↗

Hydraulic and purification behaviors and their interactions during wastewater treatment in soil infiltration systems.

Four three-dimensional lysimeters were established in a pilot laboratory with the same medium sand and either an aggregate-laden (AL) or aggregate-free (AF) infiltration surface and a 60- or 90-cm soil vadose zone depth to ground water. During 48 weeks of operation, each lysimeter was dosed 4 times daily with septic tank effluent (STE) at 5 cm/d (AL) or 8.4 cm/d (AF). Weekly monitoring was done to characterize the STE, percolate flow and composition, and water content distributions within the lysimeters. Bromide tracer tests were completed at weeks 0, 8, and 45 and during the latter two times, ice nucleating active (INA) bacteria and MS-2 and PRD-1 bacteriophages were used as bacterial and viral surrogates. After 48 weeks, soil cores were collected and analyzed for chemical and microbial properties. The observations made during this study revealed a dynamic, interactive behavior for hydraulic and purification processes that were similar for all four lysimeters. Media utilization and bromide retention times increased during the first two months of operation with the median bromide breakthrough exceeding one day at start-up and increasing to two days or more. Purification processes were gradually established over four months or longer, after which there were high removal efficiencies (>90%) for organic constituents, microorganisms, and virus, but only limited removal of nutrients. Soil core analyses revealed high biogeochemical activity within the infiltrative zone from 0 to 15 cm depth. All four lysimeters exhibited comparable behavior and there were no significant differences in performance attributable to infiltrative surface character or soil depth. It is speculated that the comparable performance is due to a similar and sufficient degree of soil clogging genesis coupled with bioprocesses that effectively purified the wastewater effluent given the adequate retention times and high volumetric utilization's of the sand media.

Soil↗