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A Eichler

Publications and source records attributed to A Eichler.

18 recordsLinked to original sources
PubMed2003

When scanning tunneling microscopy gets the wrong adsorption site: H on Rh(100).

At low tunneling resistance, scanning tunneling microscopy (STM) images of a Rh(100) surface with adsorbed hydrogen reproducibly show protrusions in all bridge sites of the surface, leading to a naive interpretation of all bridge sites being occupied with H atoms. Using quantitative low-energy electron diffraction and temperature programmed desorption we find a much lower H coverage, with most H atoms in fourfold hollow sites. Density functional theory calculations show that the STM result is due to the influence of the tip, attracting the mobile H atoms into bridge sites. This demonstrates that STM images of highly mobile adsorbates can be strongly misleading and underlines the importance of additional analysis techniques.

Journal Article↗
PubMed2003

Influence of inhaled iloprost on transpulmonary gradient of big endothelin in patients with pulmonary hypertension.

BACKGROUND: The pulmonary circulation is an important site for the production and clearance of endothelin (ET)-1, a potent vasoactive and mitogenic peptide. In healthy individuals, 40% to 50% of circulating ET-1 is removed on each passage through the lungs resulting in an arteriovenous ratio of <1, whereas many patients with pulmonary arterial hypertension (PAH) have ratios >1, indicating reduced clearance or increased release of endothelin. The influence of inhaled prostanoids on endothelin clearance is unknown. METHODS AND RESULTS: In a prospective investigation, plasma concentrations of big endothelin-1 (big ET-1, Elisa) were measured in 15 patients with pulmonary hypertension undergoing right heart catheterization with iloprost inhalation (4 m, 11 f, aged 35 to 75 years, mean pulmonary arterial pressure (PAPm) 54+/-2.3 mm Hg, pulmonary vascular resistance (PVR) 1061+/-141 dyn x sec x cm(-5)). There was a significant transpulmonary gradient for big ET-1 with 31% +/-11% higher concentrations in the radial artery than in the pulmonary artery (P<0.001). After inhalation of iloprost a significant decrease in the AV-ratio from 1.31+/-0.11 to 0.92+/-0.06 (P<0.007) was observed. The pulmonary net release of 3.10+/-0.65 pmol/min big ET-1 at baseline decreased to -1.24+/-1.32 pmol/min (P=0.013) within 15 minutes indicating a restored balance. Patients under long-term treatment with iloprost (n=7) tended to have a lower net release and AV-ratio for big ET-1 than patients without pretreatment. CONCLUSION: An increase in pulmonary clearance of big-ET could be a mechanism contributing to the beneficial effects of inhaled prostanoids in the treatment of PAH.

Administration, Inhalation↗
PubMed2002

Polyploidization and centrosome hyperamplification in inflammatory bronchi.

OBJECTIVE AND DESIGN: Inflammatory and tumorous bronchi were screened in order to obtain new tumor relevant cytogenetic parameters. MATERIAL OR SUBJECTS: Bronchial cells of 32 patients were cultivated by standard cell culture procedures. METHODS: Tetraploidy and aneuploidy was determined by enumeration of chromosome 7 and 8 versus the number of centrosomes. The resulting data were correlated with histopathological data. RESULTS: Tetra- and aneuploidy of epithelial cells were detectable in 76% of tumor cell cultures, 75% of high grade inflammatory tissues and 40% of non- and low grade-inflammatory tissues. Additionally, we observed centrosome hyper-amplification and multipolar mitoses not only in the tumor but also in the early stages of inflammation. CONCLUSION: Inflammatory bronchi already show tumor-specific features and may consequently represent the preliminary genetic stage of cancer development in bronchi.

Adult↗
PubMed2000

[Aids and anesthesia] .

17 years after the discovery of HIV Aids remains an ultimately fatal disease. Currently no vaccine is available. The worldwide incidence of HIV-infections and Aids associated mortality are rising. Only in Western Europe and in the USA are incidence and mortality of Aids declining; mainly as a result of effective antiretroviral therapy. 20% to 25% of HIV-infected patients require surgery during their illness. The challenges for the anaesthesiologist are possible dysfunction of all important organs and adverse interactions between antiretroviral drugs and anaesthetic agents. If adequate infection control measures are taken the risk of occupational HIV-infection is low, but remains a concern in light of the consequences. Seroconversion after needlestick injury is ca. 0.3%, after contact with mucosa ca. 0.03%.

Acquired Immunodeficiency Syndrome↗
PubMed2000

Sensitive detection of micrometastases in bone marrow from patients with breast cancer using immunomagnetic isolation of tumor cells in combination with reverse transcriptase/polymerase chain reaction for cytokeratin-19.

We report a highly sensitive method to detect rare human breast cancer cells, which combines an immunomagnetic separation (IMS) using antibody BM2 against MUC-1 with cytokeratin-19 (CK19) and the reverse transcriptase/polymerase chain reaction (RT-PCR). The IMS-RT-PCR technique allows the detection of 1 tumor cell/10(7)-10(8) mononuclear cells. This is at least ten times more sensitive than CK19 RT-PCR alone, or immunocytochemistry. All 117 peripheral blood and 8 bone marrow samples obtained from healthy donors as negative controls were positive for beta2-microglobulin by RT-PCR but negative for CK19 by IMS-RT-PCR or RT-PCR alone. Out of 26 bone marrow samples from breast cancer patients, 18 had CK19 transcripts detectable by IMS-RT-PCR. In contrast, only 14 and 13 samples from the 26 were found to be positive by RT-PCR alone or by routine immunocytochemical staining. In conclusion, IMS-RT-PCR for CK19 is a highly sensitive and specific method for detecting very low numbers of micrometastatic breast cancer cells in bone marrow amidst an excess of nonmalignant cells. For the early diagnosis of disseminating disease, this assay is more efficient than RT-PCR alone and routine immunocytochemistry.

Bone Marrow↗
PubMed2000

[Interferon alpha-2a in the treatment of diffuse thoracic angiomatosis in adulthood--a ase report].

A diffuse angiomatosis affecting thoracal organs is a rare, frequently fatal disorder occurring mainly in childhood. The definite diagnosis is usually made by autopsy. A specific treatment does not exist. In the case report presented here we describe the course of an 37-year old patient presenting initially with dyspnea and hemoptysis. Radiological investigations showed a mass lesion in the anterior superior mediastinum, bihilar masses and a periesophageal mass with soft tissue density and a pericardial effusion. Bilateral interstitial infiltrations were also present. CT-guided mediastinal biopsies and bronchial mucosal biopsies were nonspecific. Open-lung biopsy revealed the diagnosis of an extensive diffuse angiomatosis affecting mediastinum, pericardium and pleura. During the 18-month monotherapy with interferon-alpha 2a the patient showed significant improvements of clinical as well as laboratory and radiological parameters. The presented case confirms the experience of several authors, that the diagnosis of a diffuse thoracal authors can only be made by open lung biopsy or autopsy. The presented case also underlines the possibility of a palliative therapy of aggressive angiomatous diseases with interferon-alpha 2a.

Adult↗
PubMed1999

Non-radioactive hybridization in microwells using enzyme linked immune sorbent assay for detection of RT-PCR-amplified CK19- and CEA-mRNA.

PCR enzyme linked immune sorbent assay (ELISA) was developed for detection of RT-PCR-amplified cytokeratin 19 (CK19) mRNA and carcinoembryonic antigen (CEA) mRNA. The non-radioactive hybridization was performed in a streptavidin-coated microwell with digoxigenin-labeled PCR products and with biotin-labeled capture probe. PCR ELISA was proved to be expedient, simple, sensitive and safe for identification of CK19-, CEA-RT-PCR products. These results were proven by sequencing.

Bone Marrow Cells↗
PubMed1999

[Ketoacidosis in a 14 month old child caused by fasting].

Preoperative starvation in order to prevent pulmonary aspiration is mandatory in elective pediatric surgery. Hypoglycemia, thirst and unwellness have been reported as undesired side effects. The metabolic response towards decreasing blood-glucose concentrations in fasting children includes gluconeogenesis and production of ketone bodies to meet the energetic demand. Accumulation of beta-hydroxybutyrate und acetoacetate in blood can lead to ketoacidosis. We report a case of a severe intraoperative ketoacidosis in a fourteen months old child complicating 36 hours of starvation.

Acid-Base Equilibrium↗
PubMed1999

Evaluating GA733-2 mRNA as a marker for the detection of micrometastatic breast cancer in peripheral blood and bone marrow.

The GA733-2 gene encodes the epithelial glycoprotein 40, a homophilic cell-cell adhesion molecule, which is expressed on the surface of epithelial cells and associated with a variety of carcinomas, e.g. breast, colorectal and lung carcinomas. To test if it could serve as a tumor marker, we have analysed the expression of GA733-2 in bone marrow (BM) and peripheral blood (PB) from healthy donors, and of patients with haematological malignancies or breast cancer using reverse transcriptase-polymerase chain reaction (RT-PCR). The GA733-2 nested PCR was positive in 100% (8/8) of BM and 40% (16/40) of PB from healthy donors, in 100% (33/33) of BM from patients with breast cancer who had no evidence of distant metastases and also in BM and PB from patients with haematological malignancies. GA733-2 mRNA is not specific as a marker for the detection of breast cancer cells in BM and PB.

Amino Acid Sequence↗
PubMed1999

Analysis of sensitivity and specificity of cytokeratin 19 reverse transcriptase/polymerase chain reaction for detection of occult breast cancer in bone marrow and leukapheresis products.

PURPOSE: The work aimed to evaluate the sensitivity and specificity of the cytokeratin (CK) 19 reverse transcriptase/polymerase chain reaction (RT-PCR) for the detection of occult breast cancer in bone marrow and leukapheresis products. MATERIALS AND METHODS: Peripheral blood and bone marrow samples, obtained from 96 and 8 healthy donors respectively, served as negative controls. A total of 115 bone marrow samples and 29 leukapheresis samples from routine patients with breast cancer were analysed by CK19 RT-PCR. The PCR results were compared with those from routine immunocytology for CK8, 18, 19. RESULTS: The CK19 RT-PCR technique with primer pairs from Datta et al. (J Clin Oncol 12: 475-482, 1994), using an annealing temperature of 72 degrees C, allowed the detection of one tumour cell in 10(7) mononuclear cells. None of the control samples (96 peripheral blood and 8 bone marrow) that were positive for beta2-microglobulin by RT-PCR showed a signal for CK19. However, expression of CK19 mRNA was observed in 40.87% (70/115) of bone marrow and in 24.13% (7/29) of leukapheresis samples of patients with breast cancer. Standard immunocytology and PCR were combined for the detection of tumour cells. Five of the 65 bone marrow samples were found to be positive by CK19 RT-PCR, but were negative with the immunocytology method. CONCLUSION: RT-PCR using CK19-specific primers and optimal experimental conditions is a reliable and specific method for the detection of micrometastatic breast cancer cells.

Bone Marrow Neoplasms↗
PubMed1999

Evaluation of the reverse transcriptase/polymerase chain reaction for carcinoembryonic antigen for the detection of breast cancer dissemination in bone marrow and peripheral blood.

This study evaluated the specificity and sensitivity of the reverse transcriptase/polymerase chain reaction (RT-PCR) for carcinoembryonic antigen (CEA) for identification of breast tumour cells in bone marrow and in peripheral blood. Using one primer set from the A2/B3 domains of CEA with five to seven mismatches to other CEA-family members allowed reproducible detection of 1 colon tumour cell and 10 breast tumour cells in 10(7) mononuclear cells. Bone marrow samples from 181 patients with breast cancer were analysed by CEA-RT-PCR; 50 of these samples were analysed in parallel by routine immunocytochemistry. CEA-mRNA-positive bone marrow cells were found in 27.6% of the patients (50/181) with breast cancer. Five immunocytochemistry-positive samples were negative when analysed by CEA-RT-PCR. Limiting factors in the detection of micrometastatic breast tumour cells by CEA-RT-PCR are the heterogeneity of the tumour cells and the deficient expression of CEA in some of these cells. However, CEA-RT-PCR using the specific primer could detect 1 colon tumour cell in 1 x 10(7) normal peripheral blood mononuclear cells.

Bone Marrow↗
PubMed1996

Bilateral vertebral artery lesion after dislocating cervical spine trauma. A case report.

STUDY DESIGN: This case report illustrates the problems associated with diagnosis and management of vertebral artery injuries resulting from dislocating cervical spine trauma. OBJECTIVES: Treatment involved the principles of anterior stabilization of dislocating cervical spine fracture as well as the diagnostic procedures and therapeutic modalities appropriate for vertebral artery lesions. SUMMARY OF BACKGROUND DATA: Because vertebral artery injuries with cervical spine trauma are rarely symptomatic, they can easily be overlooked. Bilateral or dominant vertebral artery occlusion, however, may cause fatal ischemic damage to the brain stem and cerebellum. METHODS: Cervical spine dislocation was stabilized immediately after admission using internal fixation by ventral plate and corticocancellous bone graft. Immediate angiography was performed when brain stem neurologic dysfunction manifested 36 hours after surgery. The patient was treated with anticoagulation, osmotherapy, and controlled hypertension. RESULTS: A fatal outcome resulted in this case of dominant left vertebral artery occlusion. Necropsy even revealed bilateral vertebral artery damage at the level of the osseous lesion. CONCLUSIONS: The possibility of the complication of a vertebral artery lesion should be kept in mind when examining patients with cervical spine trauma, especially in patients with fracture-dislocation. Immediate identification by vertebral angiography, magnetic resonance imaging, or thin-slice computed tomography scan is necessary for optimal management of this injury.

Adult↗
PubMed1995

[Immunoscintigraphy of breast cancer xenografts. 99m-Tc-labeled anti-mucin monoclonal antibodies BM-7 and 12H12].

The present study was undertaken to evaluate the correlation of the favorable in vitro characteristics of the anti-mucin Mabs 12H12 and BM-7 with high tumor accumulation in vivo. They were labeled with 99mTc; their biodistribution in nude mice bearing mammary tumor xenograft AR was examined and immunoscintigraphy was performed after 24 h. 99mTc-labeling of the Mabs 12H12 and BM-7 led to tumor uptakes of 20.7% and 8.8% ID/g, respectively, after 48 h. Tumor-to-muscle ratios were 31 (12H12) and 18 (BM-7). Tumor xenografts were clearly visualized in immunoscintigrams. Combination of Mab 12H12 and 99mTc provides high tumor-to-tissue ratios shortly after administration.

Animals↗
PubMed1976

Behavioral disturbances among failure-to-thrive children.

The eating, sleeping, elimination, autoerotic and self-harming behavior of 19 preschool failure-to-thrive children was studied. Their behavior was compared to a group of 19 children growing normally for their chronological age. Information was obtained by repeated home visits by public health nurses. The growth-retarded children had more feeding difficulties as infants, had skimpier, less regular meals, and had poorer response to food when rated on a five-point scale. Their daily caloric intake was lower. There was no substantial differences between groups for sleeping, elimination, autoerotic, and self-harming behaviors when each area was separately analyzed. However, when all the disturbances were summed, there was clear evidence that the failure-to-thrive children had a noticeably greater number of abnormalities than the control group.

Child Behavior Disorders↗
PubMedDate not supplied

Detection of central pulmonary artery thromboemboli by transesophageal echocardiography in patients with severe pulmonary embolism.

Transthoracic echocardiography generally provides only indirect signs of pulmonary embolism. In contrast, with transesophageal echocardiography the thromboembolus itself can be visualized in the central parts of the pulmonary artery. The aims of our study were to evaluate, first, the incidence of central pulmonary artery thromboemboli in patients with severe pulmonary embolism, and second, the accuracy of the echocardiographic diagnosis. Our study group comprised 60 patients with proved severe pulmonary embolism. All patients were examined by transthoracic and transesophageal echocardiography. The echocardiographic findings concerning the absence or presence of central pulmonary artery thromboemboli were compared with the results of different reference methods. Central pulmonary thromboemboli were found in 35 patients (58.3%) by echocardiography. Two types of thrombus were differentiated. Type A is a long, highly mobile thrombus, and type B is an immobile wall-adherent thrombus. In comparison with the reference methods, we determined a sensitivity of 96.7% and a specificity of 88% for the echocardiographic detection of central pulmonary artery thromboemboli in patients with severe pulmonary embolism. Transesophageal echocardiography seems to be a useful method for the diagnosis of severe pulmonary embolism. In our series, central pulmonary artery thromboemboli were present in more than half of the patients. In these cases, transesophageal echocardiography can clarify the diagnosis within a few minutes without further invasive diagnostic procedures.

Adult↗
PubMedDate not supplied

Self-reported stress: findings from the 1985 National Health Interview Survey.

The National Health Interview Survey's 1985 Health Promotion and Disease Prevention Questionnaire included questions on the amount of stress experienced in the past 2 weeks, the effect of stress on health, thoughts about seeking help for personal or emotional problems, and actual help-seeking behaviors. This report examines responses to these questions and analyzes self-reported levels of stress by sex and other respondent characteristics. In 1985, an estimated 34 million people aged 18 years and older experienced "a lot" of stress in the 2-week period preceding the interview. Women were more likely than men to report a lot of stress (23 percent versus 18 percent), and respondents 65 years of age or older were more likely than younger respondents to report "almost no" stress. An estimated 21 million people (13 percent) believed that, over the past year, stress had "a lot" of effect on their health. Seventeen percent of the population considered seeking help in the past year for personal or emotional problems from family, friends, helping professionals, or self-help groups. Sixty-nine percent of those who thought about seeking help reported that they actually did seek help. In terms of health practices, men and women who reported higher levels of stress than others of their sex also were more likely to report that they rarely or never ate breakfast, slept 6 or fewer hours per night, were physically less active than their peers, or drank more alcoholic beverages than usual in the 2 weeks prior to the survey.

Adolescent↗