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Biomedical subjects

C Meyer

Publications and source records attributed to C Meyer.

At least 91 records · Page 5Linked to original sources
PubMed2002

Mycobacterium tuberculosis gene-amplification in breath condensate of patients with lung tuberculosis.

The applicability of Mycobacterium tuberculosis-gene-amplification test (NAT) in breath condensate (BC) was examined in lung tuberculosis (TB). Ten patients with bacteriologically confirmed lung TB have been examined by ligase chain reaction (LCx). In BC the NAT were negative in all patients as well as the examination of acid fast smears and of solid phase or liquid media cultures were. This indicates that the use of NAT in BC can not replace or complement sputum or materials obtained invasively in patients with lung TB.

Adult↗
PubMed2002

Elective laparoscopic colonic resection for diverticular disease: results of a multicenter study in 179 patients.

BACKGROUND: We undertook a retrospective multicenter study of elective laparoscopic sigmoidectomy for diverticulitis in order to assess the safety and the results of the procedure performed by a large number of surgeons. MATERIALS AND METHODS: Between January 1998 and April 1999, the French Society of Laparoscopic Surgery recruited retrospectively 179 patients from 10 surgical units, operated on for elective laparoscopic sigmoidectomy. There were 94 men and 85 women with a mean age of 58 years (range, 30-82). The indications for surgery were acute attacks in 123 cases, complicated diverticulitis in 47 cases, and miscellaneous in 9 cases. RESULTS: The performed procedure was a successful laparoscopic assisted sigmoidectomy in 154 cases (with totally intracorporeal anastomosis in 136 cases and hand-sewn anastomosis via small incision in 18 cases). The mean operation time was 223 min +/- 79 (range, 100-480). There was no mortality and 23 complications occurred in 23 patients (14.9%). Postoperative ileus lasted 2.5 +/- 0.9 days (range, 1-6), and oral intake started after 3.3 +/- 1.3 days (range, 1-12). The mean postoperative stay was 9.3 days (range, 4-50). Conversion to laparotomy was necessary in 25 cases (13.9%). The essential causes of conversion were obesity, severe adhesions, and colonic inflammation. The mean postoperative stay for the 25 converted patients was 13 +/- 8.5 days (range, 7-42). CONCLUSION: Elective laparoscopic sigmoidectomy for diverticulitis is feasible and is safe. The complication and mortality rates are similar to those observed after open procedures. For experienced surgical teams, laparoscopic colonic resection is a good approach for selected patients suffering from symptomatic diverticulitis.

Adult↗
PubMed2002

Electron paramagnetic resonance investigation of endohedral fullerenes N@C(60) and N@C(70) in a liquid crystal.

Endohedral fullerenes N@C(60) and N@C(70) were dissolved in the liquid crystal 4-methoxybenzylidene-4'-n-butylaniline (MBBA) and investigated by electron paramagnetic resonance. In both cases well resolved EPR spectra give proof for molecular orientation in the nematic mesophase. Spectral features are dominated by a nonvanishing zero-field interaction, indicating a deviation from spherical spin density distribution at the encased nitrogen atom. In N@C(70), a maximum order parameter O(33) = 0.18(3), correlated with the long axis of the cage, and a zero-field-splitting parameter D = -2.6(4) MHz were determined. A persistent zero-field splitting is also observed in C(60) via the quartet spin of the encapsulated nitrogen, although no assignment of the director with respect to the molecular frame is possible. The observed line splitting is indicative of pseudo orientation of the rapidly rotating cage in this case.

Journal Article↗
PubMed2002

[Interest in intestinal resection for treatment of advanced ovarian cancer].

AIM OF THE STUDY: Digestive surgery is often necessary for surgical management of advanced ovarian carcinoma. PATIENTS AND METHODS: In a series of 62 patients with stage III ovarian carcinoma, postoperative morbidity and mortality, overall survival after 5 years and disease-free survival after 2 years were studied and corelated with several patients criteria (age, stage of the disease, residual disease, type of surgery, CA125 normalisation delay, postoperative complications and hospital stay). Patients were divided into two groups according to the surgical treatment. The first group (n = 17) included patients treated by gynecologic and digestive surgery, the second group (n = 45) included patients treated by gynecologic surgery only. All patients were proposed for chemotherapy included platyn salt. Mean age was 60 years (range: 20-83). The stage of the cancer was stage IIIa in 7 cases, stage IIIb in ten and stage IIIc in 45. RESULTS: Postoperative mortality was 3.5% (2/62). Postoperative morbidity was 26% (13/62). No statistical differences were noted for hospital stay, general morbidity, surgical morbidity when a gastric resection or a colon resections or a splenectomy were performed. Overall survival at 5 years was 56%. Residual disease less than 2 cm3 is the only prognostic factor for overall survival (56% vs 23% [P = 0.03]) and disease-free survival (86% vs 46% [P = 0.02]). CONCLUSION: This study including 62 patients confirmed the prognostic significance of extensive cytoreductive surgery for treatment in advanced ovarian epithelial cancer without increasing the postoperative morbidy and mortality.

Adult↗
PubMed2002

[Laparoscopic treatment of large hiatal hernias using a prosthesis. Report of ten cases].

OBJECTIVE: To evaluate prospectively the laparoscopic surgery for giant hiatal hernias treated by fundoplication and hiatal prosthesis. PATIENTS AND METHODS: Ten patients were included in this study. Surgical technic included the dissection of oesophageal hiatus, the sac excision and the dissection of the abdominal oesophagus to obtain a physiological length. The decision criterion for a prosthesis was the hiatus oesophagus diameter of 5 cm or more. The crura were closed and the hiatus was reinforce by a prosthesis of 15 x 15 cm. All patients underwent a fundoplication whether partial or complete. RESULTS: Eight patients had a type III hernia, and 2 had a type II. The mean size for the hiatus was 6.5 cm (5.5-8). Eight patients underwent a total fundoplicature and 2 a partial one. The prosthesis was made of polypropylene in 5 cases. Average operating time was 182 min (78-240). One patient had postoperative morbidity, with gastroplagia which resolved. There was no mortality. Mean hospitalisation duration was 7.7 days (5-12). No one case of recurrence have been noticed after a mean follow-up of 24 months (8-40). CONCLUSION: It appears that the large size hiatal hernia (more than 5 cm) can be treated with good results by using a prosthesis during laparoscopic fundoplication.

Aged↗
PubMed2002

Elimination of mycoplasma from leukemia-lymphoma cell lines using antibiotics.

Mycoplasmal contamination of cell culture systems continues to present major problems for basic research and for manufacturing of bioproducts. Previous work suggested that certain antibiotics have strong anti-mycoplasma properties and raised the prospect that the technically rather simple antibiotic treatment may be an appropriate means for mycoplasma eradication. We have developed and validated an effective strategy to eliminate mycoplasma from chronically infected cell cultures using antibiotics which have shown strong activity against these contaminants. Here, we describe our experience with the treatment of 123 consecutive mycoplasma-positive leukemia-lymphoma cell lines, comparing five different antibiotic regimens (in total 433 treatments). We optimized the antibiotic dose schedules and the duration of treatments. The various antibiotic treatments which were employed in parallel had a high efficacy, as 71% to 86% of the infected cultures were cleansed. Treatment failure may result from the resistance of the mycoplasmas to antibiotic therapy and the inability of the eukaryotic cells to survive the cytotoxic effects of the antibiotics. Resistance to mycoplasma eradication was observed in 3% to 20% of the cultures. Loss of the cell culture caused by cytotoxicity was seen in 3% to 11% of the treatments. With regard to the overall outcome, 96% of the cell lines were rendered mycoplasma-free with at least one of the antibiotic treatments and were permanently cured. In conclusion, antibiotic treatment represents the most practical and efficient option to cleanse mycoplasma-positive cell lines.

Algorithms↗
PubMed2002

New acute myeloid leukemia-derived cell line: MUTZ-8 with 5q-.

The advent of continuous human leukemia-lymphoma cell lines as a rich resource of abundant, accessible and manipulable living cells has contributed significantly to a better understanding of the pathophysiology of hematopoietic tumors. We describe the establishment of the new continuous leukemia cell line MUTZ-8 from a patient with acute myeloid leukemia (AML): MUTZ-8 was derived from the peripheral blood of a 63-year-old woman with AML M4 (25 years after onset of myelodysplastic syndromes, MDS). DNA fingerprinting confirmed authenticity and derivation of the cell line. The immunoprofiling as determined by flow cytometry showed that MUTZ-8 is positive mainly for myeloid but also some monocytic and megakaryocytic markers, whereas it is negative for T cell, B cell and erythroid markers. The cell line is constitutively cytokine-dependent, proliferation requiring externally added cytokines. The cytokine response profiles showed a two- to 10-fold growth stimulation of the cells by various cytokines, whereas other cytokines led to growth inhibition. Cytogenetic analysis confirmed the common clonal derivation of the cell line and the malignant clone predominating at the times of sampling. MUTZ-8 displays a deletion of the 5q31 AML/MDS region effected by a non-reciprocal translocation, t(5;11)(q21;q10). The scientific utility of MUTZ-8 lies (1) in its cluster of pathognomonic cytogenetic alterations including a 5q31 breakpoint and (2) in its absolute cytokine dependency and proliferative response to various cytokines.

Aneuploidy↗
PubMed2002

[Relationship between subjectively perceived working conditions and alcohol consumption: results of the TACOS study].

The purpose of this investigation was to examine the relationship between subjectively perceived working conditions and alcohol consumption based on a stress coping model. The investigation is part of the study 'Transitions in Alcohol Consumption and Smoking' (TACOS), a representative general population survey in a Northern German region. The current evaluation includes 2,471 working individuals, aged 18-64 years. Data with regard to alcohol consumption were collected via the 'Munich Composite International Diagnostic Interview' (M-CIDI). The three scales of the 'Normative and Subjective Assessment of working analysis' (NUSA) Contents of work, Physical work conditions and Intensity of work gathered differentiated information on subjectively perceived working conditions. The ANOVA results show that alcohol consumption does not account for variance in the scales of subjective working conditions. Further correlation and regression analyses do not reveal a relationship between the scales of NUSA and the quantity of drinking.A substantial relationship between subjectively perceived working conditions and moderate alcohol consumption, alcohol abuse or alcohol dependence could not be established. The reported results appear to indicate complex and multifactorial associations between subjectively perceived working conditions and alcohol consumption. Implications for alcohol prevention in worksite environments are discussed.

Adaptation, Psychological↗
PubMed2002

[Submillimeter 3D coronary MR angiography with real-time navigator correction in 107 patients with suspected coronary artery disease].

PURPOSE: To evaluate the clinical value of high-resolution coronary MR angiography (coronary MRA) in a large group of patients with suspected coronary artery disease. METHODS AND MATERIAL: 107 patients with suspected coronary artery disease underwent free-breathing coronary MRA (Intera, 1.5 T, Philips Medical Systems). To compensate for artefacts due to respiratory motion, a right hemidiaphragmatic navigator with real time-time slice correction was used. An ECG-gated, fat-suppressed, 3D segmented-k-space gradient echo sequence (in plane resolution 0.70 x 0.79 mm(2)) was used. Cardiac catheterization with selective coronary angiography was performed in all patients. Visualization of the coronary arteries (CA) was qualitatively assessed using a four-point grading scale. RESULTS: Image quality of grade 1 was achieved in 24 %, grade 2 in 48 %, grade 3 in 24 % and grade in in 4 % of patients. Based on an evaluation of the coronary MRAs of all patients (n = 107) sensitivity and specificity for the detection of stenoses > 60 % in the proximal and middle main coronary arteries were 74 % and 63 %, respectively. In coronary MRAs with good quality [grade 1 and 2, n = 77/107 (72 %)] sensitivity and specificity for the detection of coronary stenoses were 88 % and 91 %, respectively. CONCLUSION: Submillimeter 3D coronary MRA with real-time navigator correction allows high quality imaging of the proximal and middle main coronary arteries with good sensitivity and specificity for detection of stenoses > 50 % in selected patients. However, in about 28 % of patients image quality is severely impaired.

Adult↗
PubMed2002

Syphilis 2001--a palaeopathological reappraisal.

The origin and subsequent spread of the treponematoses, especially that of venereal syphilis, has been the subject of considerable scientific attention. Various theories were put forth and palaeopathological specimens were used for their validation in recent times. One influential contribution was the paper by Baker & Armelagos in 1988. Numerous new findings and results on both sides of the Atlantic call for a new evaluation of the available osseous material. A review of the recent literature leads to the suggestion of a worldwide distribution of non-venereal treponemal disease since the emergence of Homo and to a first epidemic outbreak of venereal syphilis in Europe of the late 15th and the early 16th century, which was a time of change and enormous sexual liberty. Old World specimens with pathological alterations attributed to venereal syphilis and dated to precolumbian times seem to invalidate the Columbian theory and call for a more differentiated analysis of the phenomenon of syphilis than a theory based on a single factor can provide. With the help of molecular methods which now allow a positive identification of Treponema pallidum pallidum, causative agent of venereal syphilis, in palaeopathological material, it seems possible to elucidate the matter of origin and spread of syphilis further and to evaluate previous diagnoses of treponemal disease.

Anthropology, Physical↗
PubMed2002

GM-CSF versus G-CSF: engraftment characteristics, resource utilization, and cost following autologous PBSC transplantation.

BACKGROUND: G-CSF and GM-CSF have both been shown to decrease the time to hematopoietic recovery when administered after autologous BM or peripheral stem cell re-infusion. However, few studies have compared G-CSF and GM-CSF to determine which is the preferred myeloid growth factor. METHODS: This study compares a prospectively accrued cohort of 22 patients receiving GM-CSF with a historical cohort of patients who received G-CSF commencing Day + 6 after autologous PBSC transplantation. Patients were matched based on disease type and stage, CD34(+) cell dose/kg, conditioning regimen, and prior treatment. Time to myeloid engraftment, growth factor utilization, antibiotic utilization, fever incidence, and cost were compared. RESULTS: The median time to neutrophil and platelet engraftment was similar in the two groups (ANC > 500 /mm(3), GM-CSF 12 versus G-CSF 11, P = 0.69). There was a trend towards more days of temperature > 38.0 masculine C (six versus three, P = 0.05) and febrile neutropenia (three versus two, P = 0.06) in the GM-CSF arm. There was a trend towards increased use of i.v. antibiotics in the GM-CSF cohort (7.6 days versus 5.5 days, P = 0.06). More chest X-rays (1.5 versus 1.0, P = 0.03) were ordered, and more blood cultures drawn (4.2 versus 2.7, P = 0.05) as part of fever evaluation in the group treated with GM-CSF. Resource utilization based on actual wholesale pricing (AWP) favored the G-CSF cohort. Applying a sensitivity analysis, GM-CSF became cost-effective when priced below $94 per 250 micro g, despite greater resource utilization. DISCUSSION: This study suggests that engraftment characteristics are similar with GM-CSF and G-CSF following PBSC transplantation. Resource utilization for fever treatment and evaluation may be greater with GM-CSF. Determination of which agent is more cost-effective depends on institutional acquisition costs.

Adolescent↗
PubMed2002

In vitro and in vivo efficacy of photofrin and pheophorbide a, a bacteriochlorin, in photodynamic therapy of colonic cancer cells.

This study was designed to investigate the efficacy of photodynamic therapy (PDT) in treating colonic cancer in a preclinical study. Photofrin, a porphyrin mixture, and pheophorbide a (Ph a), a bacteriochlorin, were tested on HT29 human colonic tumor cells in culture and xenografted into athymic mice. Their pharmacokinetics were investigated in vitro, and the PDT efficacy at increasing concentrations was determined with proliferative, cytotoxic and apoptotic assessments. The in vivo distribution and pharmacokinetics of these dyes (30 mg/kg, intraperitoneal) were investigated on HT29 tumor-bearing nude mice. The inhibition of tumor growth after a single 100 J/cm2 PDT session was measured by the changes in tumor volume and by histological analysis of tumor necrosis. PDT inhibited HT29 cell growth in culture. The cell photodamage occurred since the time the concentrations of Ph a and Photofrin reached 5.10(-7) M (or 0.3 microg/mL) and 10 microg/mL, respectively. A photosensitizer dose-dependent DNA fragmentation was observed linked to a cleavage of poly(ADP-ribose) polymerase and associated with an increased expression of mutant-type p53 protein. PDT induced a 3-week delay in tumor growth in vivo. The tumor injury was corroborated by histological observation of necrosis 48 h after treatment, with a correlated loss of specific enzyme expression in most of the tumor cells. In conclusion, PDT has the ability to destroy human colonic tumor cells in vitro and in vivo. This tumoricidal effect is likely associated with a p53-independent apoptosis, as HT29 cells express only mutated p53. The current study suggests a preferential use of Photofrin in PDT of colonic cancer because it should be more effective in vivo than Ph a as a consequence of better tumor uptake.

Animals↗
PubMed2001

Screening for mental health: validity of the MHI-5 using DSM-IV Axis I psychiatric disorders as gold standard.

Short screening questionnaires for mental health are useful tools for research and clinical practice, e.g. they could play a major role in detecting patients with psychiatric disorders in primary care. The present study tests the validity of the five-item Mental Health Inventory (MHI-5) screening test using DSM-IV Axis I diagnoses as a gold standard and analyzes its performance in different diagnostic groups. A random sample was drawn from the resident registration office files in northern Germany. Personal interviews with a response rate of 70% were conducted. Of the sample, 4036 respondents filled in the MHI-5. DSM-IV diagnoses were assessed using the Munich Composite International Diagnostic Interview (M-CIDI). The area under the receiver operating characteristics curve (AUC) of 0.72 in identifying any DSM-IV Axis I disorder (except substance use) is not satisfying. The MHI-5 revealed best performance for mood (AUC: 0.88) followed by anxiety disorders (AUC: 0.71). Sensitivity and specificity were poor for somatoform and substance use disorders, especially in cases without comorbid mood or anxiety disorder. The power to detect mood and anxiety disorders of the MHI-5 was better for the 4-week compared with the 12-month diagnoses. The MHI-5 can be recommended to screen for mood disorders. Data have to be confirmed for primary care settings.

Adolescent↗
PubMed2001

Anti-proliferative effects of new staurosporine derivatives isolated from a marine ascidian and its predatory flatworm.

Nine indolocarbazole alkaloids of the staurosporine type, including three new derivatives, were evaluated for their potential as inhibitors of cell proliferation and macromolecule synthesis. Four derivatives were tested as inhibitors of cell proliferation with twelve human leukemia cell lines and demonstrated powerful antiproliferative activities, with 3-hydroxystaurosporine being the most potent. IC(50) values were determined using the cell line MONO-MAC-6 and with an IC(50) of 13 ng/ml, 3-hydroxystaurosporine turned out to be one of the most active staurosporine-type inhibitors described so far. All derivatives, except 3-hydroxy-3'-demethoxy-3'-hydroxystaurosporine and 4'-N-methylstaurosporine very strongly reduced RNA and DNA synthesis with 3-hydroxystaurosporine again being the strongest inhibitor. Analysis of structure-activity relationships demonstrated that hydroxylation of staurosporine at position 3 of the indolocarbazole moiety caused an increase in anti-proliferative activity, while hydroxylation at carbon 11 resulted in a decrease in activity. Our results suggest that not only the presence or absence of hydrophilic substitutions, but also the position of the alteration within the molecule, is important in the antiproliferative properties of the various staurosporine analogues.

Animals↗
PubMed2001

Epitope mapping and affinity purification of monospecific antibodies by Escherichia coli cell surface display of gene-derived random peptide libraries.

We report a method for the precise mapping of linear epitopes by presenting a peptide library on the surface of Escherichia coli cells. A random library of gene fragments derived from the classical swine fever virus (CSFV) envelope protein E(rns) was generated by DNAse I cleavage and cloned into a specially designed bacterial surface display vector. A carboxyterminally truncated intimin, an adhesin from enteropathogenic E. coli, serves as a carrier protein to present foreign peptides on the surface of E. coli K12 cells. Epitope-presenting cells were isolated by immunofluorescence staining of the bacterial cell population with monoclonal anti-E(rns) antibodies followed by fluorescence-activated cell sorting (FACS). Nucleotide sequence analysis of the coding sequence for the cloned target gene fragments of a few FACS-positive clones allowed the identification of the respective epitope sequence. A major linear antigenic determinant of the E(rns) protein could be identified by epitope mapping with a polyclonal anti-E(rns) serum. Furthermore, the high-density surface display of intimin-peptide fusions allowed us to use epitope-presenting bacteria directly as whole cell adsorbants for affinity purification of monospecific antibodies. Monospecific antibodies directed against the carboxyterminal fragment of E(rns) were isolated and used for immunostaining of transfected BHK-21 cells to validate the transient expression of E(rns). This demonstrates that gene-fragment libraries displayed on E. coli cells as fusion proteins with intimin are useful tools for rapid mapping of linear epitopes recognized by monoclonal antibodies (MAbs) and polyclonal sera and for the affinity purification of monospecific antibodies by adsorption to the E. coli surface exposed antigenic peptide.

Amino Acid Sequence↗
PubMed2001

Microstructured glass chip for ion-channel electrophysiology.

We present a technique by which it is possible to produce a planar sensor for ion channel electrophysiology from glass substrates. Apertures with diameters in the low micrometer to submicrometer range are achieved by irradiation of a glass chip with a single heavy ion and subsequent wet track etching. The function of the device is demonstrated by recordings of single channel currents mediated by the model ion channel gramicidin A in lipid bilayers spanning the micromachined aperture.

Electrolytes↗