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1.
Earth Space Sci ; 8(4): e2020EA001235, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34222559

RESUMO

The Advanced Topographic Laser Altimetry System (ATLAS) is the sole instrument on the Ice, Cloud, and land Elevation Satellite 2 (ICESat-2). Without some method of reducing the transmitted data, the volume of ATLAS telemetry would far exceed the normal X-band downlink capability or require many more ground station contacts. The ATLAS Onboard Flight Science Receiver Algorithms (hereinafter Receiver Algorithms or Algorithms) control the amount of science data that is telemetered from the instrument, limiting the data volume by distinguishing surface echoes from background noise, and allowing the instrument to telemeter data from only a small vertical region about the signal. This is accomplished through the transfer of the spacecraft's location and attitude to the instrument every second, use of an onboard Digital Elevation Model, implementation of signal processing techniques, and use of onboard relief and surface type reference maps. Extensive ground testing verified the performance of the Algorithms. On-orbit analysis shows that the Algorithms are working as expected from the ground testing; they are performing well and meeting the mission requirements.

2.
J Cell Biol ; 96(5): 1218-26, 1983 May.
Artigo em Inglês | MEDLINE | ID: mdl-6341376

RESUMO

We studied a rat Schwannoma cell line (RN22F) to determine if it produced the basement membrane glycoproteins laminin and fibronectin, and how it interacted with these proteins in vitro. We used antisera to laminin and fibronectin for immunoprecipitation experiments and immunocytochemical localization at the electron microscope level. Polyacrylamide gels of antilaminin immunoprecipitates of conditioned medium and solubilized Schwannoma cells contained bands of reduced Mr 200,000 and 150,000. Antilaminin immunoprecipitates of conditioned medium contained nonreduced bands of 850,000 daltons and 150,000, and immunoprecipitates of solubilized cells contained nonreduced bands of 850,000, 400,000, 200,000, and 150,000 daltons. Antifibronectin immunoprecipitates of conditioned medium contained a reduced band of 220,000 daltons, and nonreduced bands of 440,000 and 220,000 daltons. Radio-labeled protein was not detected in antifibronectin immunoprecipitates of solubilized cells. By immunocytochemistry, laminin was found along the cell surface in a continuous band, whereas fibronectin was only sparsely distributed along the cell surface. In cell adhesion assays, Schwannoma cells bound preferentially to laminin-coated substrates as compared to fibronectin or noncoated substrates. A number of Schwannoma cells displayed a curved and elongated morphology on laminin substrates, as compared to a uniformly spread morphology on fibronectin, and a round, nonspread morphology on noncoated substrates. Immunofluorescent staining showed laminin in the endoneurium and perineurium and fibronectin predominantly in the perineurium of mouse sciatic nerve in vivo. The production of laminin and fibronectin by Schwann cells may be important in the development and myelination of peripheral nerves, and the proper regeneration of axons following nerve injury.


Assuntos
Fibronectinas/biossíntese , Glicoproteínas/biossíntese , Células de Schwann/citologia , Nervo Isquiático/análise , Animais , Imunofluorescência , Laminina , Camundongos , Microscopia Eletrônica , Peso Molecular , Ratos , Células de Schwann/metabolismo
3.
J Cell Biol ; 97(3): 772-7, 1983 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6885918

RESUMO

Laminin is a large (greater than 850-kdalton) glycoprotein that is localized within basement membranes. Recent work has indicated that this protein is present within the endoneurium of mouse sciatic nerve. Furthermore, it has been shown that a rat Schwannoma cell line, RN22F, produced laminin and that laminin promoted the attachment of these cells to bacterial plastic. This report presents evidence that RN22F cells migrate in vitro to laminin in a concentration-dependent fashion. Laminin was extracted from the mouse EHS tumor and purified by molecular sieve and heparin-agarose affinity chromatography. The migration of Schwannoma cells to laminin, as assessed in a microwell modified Boyden chamber, was inhibited in a dose-dependent manner by affinity-purified antilaminin antibody. Zigmond-Hirsch checkerboard analysis experiments indicated that laminin stimulated both random and directed movement of RN22F cells. Additionally, reversal of the laminin gradient in the chambers also stimulated RN22F migration in a concentration-dependent manner, suggesting that directed migration of RN22F cells was due to a substratum-bound laminin (haptotaxis) as opposed to cell movement in response to fluid-phase laminin (chemotaxis). Binding studies using [3H]laminin demonstrated that laminin bound to the filter surface under the assay conditions used, and support the contention that cells are migrating to substrate-bound material. Furthermore, RN22F cells were shown to migrate on filters coated with laminin in the absence of additional fluid-phase laminin. The magnitude of this response could be altered by changing the relative density of bound laminin. In contrast, fibronectin promoted only marginal migration of RN22F cells. Collectively, these observations indicate that haptotaxis may be a mechanism by which laminin may guide cells during development and raise the possibility that it may be involved in peripheral nervous system myelination.


Assuntos
Membrana Basal/fisiologia , Glicoproteínas/fisiologia , Neurilemoma/fisiopatologia , Animais , Movimento Celular , Quimiotaxia , Relação Dose-Resposta a Droga , Fibronectinas/fisiologia , Laminina , Neoplasias Experimentais/fisiopatologia , Ratos
4.
Heredity (Edinb) ; 103(1): 82-9, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19417764

RESUMO

Previous studies of genetic structure in the European eel have resulted in seemingly conflicting results, ranging from no detectable heterogeneity to small but statistically significant differences and isolation by distance patterns among eels sampled across the continental range. Differences with respect to sampling design and choice of molecular markers, combined with a lack of power estimates, complicate comparisons of existing results. In this study we have used six microsatellite markers and, for the first time, compared maturing silver eels of known age from southern and northern Europe (Italy and Baltic Sea). In comparison with previous studies, our data may give a better representation of potential spawning stocks because eels were sampled when having begun their migration toward the presumed spawning area in the Sargasso Sea. Despite large sample sizes (404 and 806 individuals) we could not observe any signs of genetic differentiation (average F(ST)=-0.00003, P=0.61), and a power analysis showed that the true level of heterogeneity (if existing) must be exceedingly small to have remained undetected (say, F(ST) <0.0004). A tendency for slightly increased genetic differences between cohorts over time could be seen, but the amount of temporal change was minor and not statistically significant. Our findings reiterate the notion that previous reports of continental genetic differentiation in the European eel may be largely explained by uncontrolled temporal variation between juvenile glass eel samples.


Assuntos
Enguias/genética , Comportamento Sexual Animal , Animais , Enguias/fisiologia , Europa (Continente) , Feminino , Variação Genética , Masculino , Repetições de Microssatélites , Dinâmica Populacional
5.
Radiat Res ; 191(4): 335-341, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30730283

RESUMO

To elucidate the potential influence of stimulating bone marrow before cell-cycle-dependent irradiation, we sought to determine overall survival in mice receiving total-body irradiation (TBI) when administered granulocyte stimulating factor (G-CSF) at different time points. Gender differences were also studied. C57/BL/6J mice, aged 9-14 weeks, received 8 Gy TBI in a perspex cage using a linear accelerator. In each of five different experiments, three groups were studied: 1. one control group receiving TBI only; 2. one group treated with filgrastim [500 lg/kg subcutaneously/intraperitoneally (s.c./i.p.)] the day before TBI, followed by daily filgrastim injections postirradiation (1-5 days); and 3. one group treated with daily filgrastim injections only post-TBI (1-5 days). Each experimental group included male and female mice. Survival of the mice was monitored daily, and mice were euthanized when their condition deteriorated. A total of 293 mice were monitored for at least 37 days post-TBI. Control mice that received 8 Gy TBI showed a significant gender difference, with a median survival of 22 days in females and 17 days in males. Addition of G-CSF, irrespective of pre- or postirradiation, significantly improved survival, but in males the improvement was significantly better when G-CSF was not given before TBI. Improved survival in females was independent of the order of administration of GCSF. Multiple filgrastim injections were more effective than a single injection, and s.c. administration was not better than i.p. In conclusion, these findings indicate that male mice are more sensitive to TBI than females. Filgrastim improved survival in both genders irrespective of whether given pre- or postirradiation, but in males the improvement was significantly less if an injection was given before irradiation. These results suggest that, to prevent toxicity most effectively, GCSF should not be given before cytotoxic therapy. While a completely different experimental model was used here, these results may also be extrapolated to indicate that endocrine cell-cycle suppression therapy should not be given before or during cytotoxic therapy of hormone-dependent tumors (e.g., breast and prostate cancer), thus a reduction in the efficacy of cell-cycle-dependent therapy can be prevented.


Assuntos
Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Fator Estimulador de Colônias de Granulócitos/farmacologia , Tolerância a Radiação/efeitos dos fármacos , Caracteres Sexuais , Animais , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Análise de Sobrevida , Irradiação Corporal Total/efeitos adversos
6.
Ann ICRP ; 48(1): 5-95, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31565950

RESUMO

Radiopharmaceuticals are increasingly used for the treatment of various cancers with novel radionuclides, compounds, tracer molecules, and administration techniques. The goal of radiation therapy, including therapy with radiopharmaceuticals, is to optimise the relationship between tumour control probability and potential complications in normal organs and tissues. Essential to this optimisation is the ability to quantify the radiation doses delivered to both tumours and normal tissues. This publication provides an overview of therapeutic procedures and a framework for calculating radiation doses for various treatment approaches. In radiopharmaceutical therapy, the absorbed dose to an organ or tissue is governed by radiopharmaceutical uptake, retention in and clearance from the various organs and tissues of the body, together with radionuclide physical half-life. Biokinetic parameters are determined by direct measurements made using techniques that vary in complexity. For treatment planning, absorbed dose calculations are usually performed prior to therapy using a trace-labelled diagnostic administration, or retrospective dosimetry may be performed on the basis of the activity already administered following each therapeutic administration. Uncertainty analyses provide additional information about sources of bias and random variation and their magnitudes; these analyses show the reliability and quality of absorbed dose calculations. Effective dose can provide an approximate measure of lifetime risk of detriment attributable to the stochastic effects of radiation exposure, principally cancer, but effective dose does not predict future cancer incidence for an individual and does not apply to short-term deterministic effects associated with radiopharmaceutical therapy. Accident prevention in radiation therapy should be an integral part of the design of facilities, equipment, and administration procedures. Minimisation of staff exposures includes consideration of equipment design, proper shielding and handling of sources, and personal protective equipment and tools, as well as education and training to promote awareness and engagement in radiological protection. The decision to hold or release a patient after radiopharmaceutical therapy should account for potential radiation dose to members of the public and carers that may result from residual radioactivity in the patient. In these situations, specific radiological protection guidance should be provided to patients and carers.


Assuntos
Exposição à Radiação/prevenção & controle , Proteção Radiológica/normas , Compostos Radiofarmacêuticos/uso terapêutico , Humanos , Guias de Prática Clínica como Assunto
7.
J Natl Cancer Inst ; 80(2): 108-16, 1988 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-3343686

RESUMO

Tumor cell metastasis is a complex process that depends in part on tumor cell adhesion to components of basement membranes and the extracellular matrix. Previous studies have indicated that the experimental metastasis of murine melanoma cells can be inhibited by ex vivo pretreatment of cells with purified adhesion-promoting fragments of laminin or the synthetic peptide arginyl-glycyl-aspartyl-serine (RGDS) prior to tail vein injection. This study extended the earlier reports to demonstrate that adhesion-promoting fragments of laminin and fibronectin can inhibit the metastasis of a tumor of different histologic origin, such as murine fibrosarcoma cells. Furthermore, ex vivo pretreatment of cells with a purified 33-kDa heparin-binding fragment of fibronectin, which promotes tumor cell adhesion by an RGDS-independent mechanism, was effective at inhibiting experimental melanoma and fibrosarcoma pulmonary metastases. The survival rate of animals receiving tumor cells pretreated with this fragment was significantly enhanced relative to control groups. As with previous studies, the mechanism of inhibition appeared to involve an increased clearance rate of tumor cells from the pulmonary microcirculation. These results suggest a role for cell surface proteoglycans in the adhesion and metastasis of certain malignant neoplasms. Furthermore, this study emphasizes the complexity of tumor metastasis and suggests that multiple strategies may be developed to inhibit hematogenous metastasis formation.


Assuntos
Fibronectinas/farmacologia , Heparina/metabolismo , Laminina/farmacologia , Metástase Neoplásica , Oligopeptídeos/farmacologia , Fragmentos de Peptídeos/farmacologia , Animais , Adesão Celular , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Células Tumorais Cultivadas
8.
Neurosurgery ; 45(4): 875-81; discussion 881-2, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10515483

RESUMO

OBJECTIVE: Meningospinal and cranial dural adhesions were compared in a canine model, after duraplasty using nonpenetrating clips or penetrating needles and sutures. METHODS: Fourteen dogs underwent bilateral craniotomies and duraplasties, with implantation of dural prostheses (DuraGuard; Biovascular Corp., Minneapolis, MN), using either 6-0 silk sutures or titanium clips (DuraClose; Surgical Dynamics, Norwalk, CT). Fourteen other dogs underwent L3-L4 laminectomies; three longitudinal dural incisions were closed with 6-0 silk sutures, 6-0 polyglactin 910 (Vicryl) sutures, or clips. Groups of eight dogs (four cranially treated and four spinally treated) were killed 6, 12, 24, and 52 weeks after surgery, and specimens were collected for study after perfusion and fixation (two cranial and two spinal dural reconstructions at 52 wk). Evaluations included assessment of the appearance of approximated dural margins and responses to clips, sutures, and dural prostheses (inflammation, foreign body reaction, fibrosis, and severity of meningospinal/meningocerebral adhesions). Data were evaluated using the Wilcoxon signed-rank and McNemar tests. RESULTS: Duraplasties with clips displayed significantly less extensive acute and chronic inflammation, foreign body reaction, and meningoneural adhesions than did repairs with needles and sutures. CONCLUSION: This report is the first long-term experimental study comparing two fundamentally different methods for dural repair in a relevant animal model.


Assuntos
Craniotomia/instrumentação , Dura-Máter/cirurgia , Complicações Pós-Operatórias/prevenção & controle , Instrumentos Cirúrgicos , Técnicas de Sutura/instrumentação , Animais , Encéfalo/patologia , Colágeno , Cães , Dura-Máter/patologia , Microscopia Eletrônica de Varredura , Agulhas , Neurônios/patologia , Complicações Pós-Operatórias/patologia , Medula Espinal/patologia , Suturas , Aderências Teciduais , Cicatrização/fisiologia
9.
Anticancer Res ; 21(1A): 409-12, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11299770

RESUMO

The purpose of the present study was to compare the therapeutic efficacy of the alpha-emitter Astatine-211 with the beta-emitter Iodine-131 bound to the specific monoclonal antibody MOv18. The measurements were performed in an ovarian cancer cell line (NIH:OVCAR 3) growing intraperitoneally in nude mice. Two weeks after the intraperitoneal inoculation of 1 x 10(7) cells of the human ovarian cancer cell line NIH:OVCAR-3 twenty mice were treated intraperitoneally with the specific monoclonal antibody MOv-18 labelled with either 211At (310-400 kBq) or 131I (5100-6200 kBq). The pharmacokinetics and biodistribution of labelled antibody in tumour-free animals were studied and the resulting bone marrow dose was estimated. When the mice were treated with 211At-labelled antibody 9 out of 10 mice were free of macro- and microscopic tumour compared to 3 out of 10 when Iodine-131 was used. The equivalent dose to the bone marrow was 2.4-3.1 Sv from 211At- and 3.4-4.1 Sv from 131I-irradiation. The therapeutic efficacy of 211At-labelled specific antibody is very good and, at approximately equivalent bone marrow doses, better than that of 131I.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Astato/uso terapêutico , Imunoconjugados/uso terapêutico , Neoplasias Ovarianas/radioterapia , Neoplasias Peritoneais/radioterapia , Radioimunoterapia , Partículas alfa/uso terapêutico , Animais , Anticorpos Monoclonais/farmacocinética , Anticorpos Monoclonais Murinos , Partículas beta/uso terapêutico , Medula Óssea/efeitos da radiação , Divisão Celular/efeitos da radiação , Feminino , Humanos , Imunoconjugados/farmacocinética , Radioisótopos do Iodo/uso terapêutico , Camundongos , Camundongos Nus , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Neoplasias Peritoneais/metabolismo , Neoplasias Peritoneais/secundário , Dosagem Radioterapêutica , Células Tumorais Cultivadas
10.
Anticancer Res ; 18(3A): 1671-6, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9673388

RESUMO

BACKGROUND: The aim of this study was to investigate the biological effect of the alpha-particle-emitting isotope astatine-211 on the human cell line Colo-205 and to compare it with that of low-dose-rate gamma-radiation. MATERIALS AND METHODS: Plastic (PMMA) rotating phantoms were constructed, allowing precise dosimetry on a cellular level for both types of radiation. Growth assays using 96-well plates were used to estimate apparent cell survival for the two types of radiation. From this, the relative biological effect (RBE) could be estimated. RESULTS: Irradiation of the cells with 211At resulted in an RBE of 25.1 +/- 6.7 at 37% survival, and 17.3 +/- 2.5 at 10% survival, when compared with low-dose-rate gamma-irradiation. The absorbed dose at 37% survival, 0.12 Gy, corresponds to 2.2 traversals of alpha-particles through the cell nuclei. For cells irradiated with gamma-radiation (1 and 2 Gy), an apparent cell survival above unity was observed up to 50 hours post-irradiation, indicating a possible radiation hormesis effect. CONCLUSIONS: The RBE of 211At found in this growth-assay study was significantly higher than previously presented values. The difference might be due to the use of low-dose-rate gamma-radiation as reference. The RBE presented here could prove valuable when evaluating 211At-labelled compounds for radiotherapy.


Assuntos
Partículas alfa , Astato , Divisão Celular/efeitos da radiação , Sobrevivência Celular/efeitos da radiação , Neoplasias do Colo , Raios gama , Humanos , Imagens de Fantasmas , Polimetil Metacrilato , Fatores de Tempo , Células Tumorais Cultivadas
11.
Anticancer Res ; 20(3A): 1807-12, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10928111

RESUMO

Cell growth kinetics following Astatine-211 (211At, alpha-particle emitter) and photon irradiation were studied for the human colorectal cell line Colo-205. A growth assay using 96-well plates was chosen. The growth kinetics could be simulated by assuming certain fractions of cells with various proliferative capacities, i.e. from none up to 5 cell doublings, in addition to the defined survivors with remaining unlimited clonogenic capacity. No significant difference in cell growth characteristics was seen between 211At and photon irradiation. The cell doubling time, as calculated from the increment in optical density, was compared with the results from BrdU experiments in the early phases of growth (Tpot = 18.5 +/- 0.6 h for LDR (low dose rate) photon irradiated and 20.3 +/- 0.8 hours for sham-irradiated cells 40-45 hours post-irradiation) confirming the transient accelerated growth of irradiated cells. No statistically significant difference in growth was found between LDR, MDR (medium dose rate) and HDR (high dose rate) photon irradiation.


Assuntos
Partículas alfa , Astato/química , Divisão Celular/efeitos da radiação , Fótons , Ciclo Celular/efeitos da radiação , Sobrevivência Celular/efeitos da radiação , Neoplasias Colorretais , Relação Dose-Resposta à Radiação , Humanos , Células Tumorais Cultivadas
12.
Anticancer Res ; 20(2A): 1005-12, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10810388

RESUMO

BACKGROUND: The aim of this study was to perform various 211At irradiations of importance for the evaluation of 211At-radioimmunotherapy, and compare the effect with that of low linear energy transfer (LET) radiation. MATERIALS AND METHODS: All irradiations were performed on low-concentration single-cell suspensions. Growth assays using 96-well plates were used to estimate apparent cell survival. Centrifuge tube filters were used to estimate the cell uptake and binding of 211At. RESULTS: A relative biological effect (RBE) of 12 +/- 2 (Colo-205) and 5.3 +/- 0.7 (OVCAR-3) was found from 211At-albumin irradiations. There was a 174 +/- 28 times higher free 211At concentration in the cell fraction than in the surrounding medium. For 211At-MAb, an 8,000-30,000 times higher concentration in the cell fraction was achieved, compared to the medium. Corrected for the uptake, an average of 31 +/- 2 ([211At]-astatine) or 26 +/- 5 ([211At]-MAb) decays per cell were required for 37% survival of Colo-205 cells. An average of 19 +/- 3 decays ([211At]-astatine) were required per OVCAR-3 cell. CONCLUSIONS: Cell uptake and binding of 211At was unexpectedly high, possibly favouring its therapeutic use. The binding is probably to the cell surface. The RBE is 5.3 +/- 0.7 for OVCAR-3 and 12 +/- 2 for Colo-205 cells.


Assuntos
Astato/toxicidade , Sobrevivência Celular/efeitos da radiação , Compostos Radiofarmacêuticos/toxicidade , Anticorpos Monoclonais , Astato/farmacocinética , Divisão Celular/efeitos da radiação , Núcleo Celular/patologia , Núcleo Celular/efeitos da radiação , Núcleo Celular/ultraestrutura , Tamanho Celular/efeitos da radiação , Neoplasias do Colo , Feminino , Humanos , Neoplasias Ovarianas , Fótons , Radioimunoterapia , Compostos Radiofarmacêuticos/farmacocinética , Células Tumorais Cultivadas
13.
Chronobiol Int ; 13(6): 423-34, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8974188

RESUMO

Fourteen healthy male subjects were studied under resting conditions for 24 or 48 h. The 24-h variations of ACTH and cortisol with peaks in the morning were confirmed. Interleukin-2 release was profoundly reduced at 8: 00. A cosine function could be fitted to lymphocyte subpopulations including populations such as T helper-memory cells (CD4+/CDw29) and HLA-DR-bearing cells displaying peak values during the night and minimal values at 9:00. Numbers of natural killer cells (CD57) were not correlated to other cell populations and no rhythm could be detected. Interleukin- 1 beta was detectable in some plasma samples only with an interleukin- 1 ELISA kit (Quantakine HS(R)), but neither a 24-h rhythm nor reproducible results could be obtained for day 1 and 2 of the study. We conclude that there might be a temporal relation between the parameters analyzed: Higher levels of endogenous cortisol in the morning hours probably inhibit the cellular interleukin-2 synthesis and are responsible for an enhanced migration of lymphocytes from the blood into the tissues of the reticuloendothelial system. These results might be indicative of a circadian organization of the immune system which may play a role in both physiological and pathological functioning.


Assuntos
Ritmo Circadiano/imunologia , Citocinas/sangue , Subpopulações de Linfócitos/imunologia , Hormônio Adrenocorticotrópico/sangue , Adulto , Humanos , Hidrocortisona/sangue , Técnicas In Vitro , Interleucina-1/sangue , Interleucina-2/sangue , Contagem de Linfócitos , Masculino , Fito-Hemaglutininas/farmacologia
14.
Rofo ; 174(6): 767-75, 2002 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-12063609

RESUMO

BACKGROUND: In 1994, 5 % of a total of 25 718 examinations and 7 % of all 4630 B-mode sonograms performed in the Radiology Department, University of Cologne was classified as not indicated. In light of these results, the health care policy guidelines for sonographic indications have been amended. PURPOSE: The aim of this study was to establish the current rate of non-indicated sonographic examinations performed in routine diagnostics by radiology departments at university hospitals, to determine the reasons for such over-diagnosis and identify which regulatory mechanisms can be implemented to prevent his. METHOD: We counted the number of 1) B-mode and 2) color-flow Doppler ultrasound imaging procedures carried out in patients who had had no change in symptoms within the previous 4 weeks or who were scheduled without reference to an existing sonogram (double examinations). 3) The reasons for over-diagnosis were analyzed. 4) The 1994 survey was repeated in 2000 with an identical protocol and 5) additionally, a modified survey of the diagnostic questions was conducted. RESULTS: 1) Out of 4,119 patients presenting for the first time to receive a B-mode sonogram, 443 prior sonograms (11 %), 305 CT scans (7 %) and 57 MRI scans (1 %) were documented. 2) Double sonograms were carried out in 6 % of the 1,118 patients presenting for the first time for color-flow Doppler ultrasounds and in 16 % of the 651 patients assigned to receive catheter angiographies with arterial color-flow Doppler. 2) 41 out of 55 (75 %) prior sonograms from non-university settings stated by 94 surgery patients were listed in the medical records. 36 out of 43 (84 %) prior sonograms from the university hospital were repeated in the same patients despite the fact that the medical report with the findings was available. None of the 48 sonograms indicated to confirm a plausible finding yielded any information that was additionally relevant to therapy. 4) In the period April - June, 2000, 12 % of all 15,921 tests and interventions, 26 % of 3,569 B-mode sonograms and 58 % of 1,033 abdominal sonograms performed in adults were classified as having not been indicated. 5) Staging and follow-up were stated as the most common reasons that a sonography was carried out in 46 % of the 1,017 adults who were given B-mode sonograms conducted from Jan - Mar, 2000 and comprised 62 % of the 410 sonograms classified as not or probably not medically indicated. CONCLUSION: The results showed that a multidisciplinary consensus was required to establish the diagnostic value of sonographic procedures. Therefore, this research group drafted a hospital-internal interdisciplinary guideline for "abdominal transcutaneous B-mode sonography in oncological questions".


Assuntos
Mau Uso de Serviços de Saúde/estatística & dados numéricos , Programas Nacionais de Saúde/estatística & dados numéricos , Serviço Hospitalar de Radiologia/estatística & dados numéricos , Ultrassonografia Doppler em Cores/estatística & dados numéricos , Ultrassonografia/estatística & dados numéricos , Diagnóstico por Imagem/estatística & dados numéricos , Feminino , Alemanha , Humanos , Masculino , Estadiamento de Neoplasias , Neoplasias/diagnóstico por imagem , Neoplasias/patologia , Guias de Prática Clínica como Assunto , Revisão da Utilização de Recursos de Saúde
15.
Methods Find Exp Clin Pharmacol ; 19(4): 269-73, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9228653

RESUMO

Morphine is suggested to influence immune function by activation of hypothalamic-pituitary-adrenal axis. Thus, we investigated 8 pain patients prior to and during prolonged oral treatment with 30-240 mg of sustained release morphine for plasma concentrations of adrenocorticotropic hormone and serum concentrations of cortisol. Results revealed that pain patients at basal status had elevated cortisol concentrations. Hormone concentrations measured after 1, 4 and 12 weeks of morphine treatment were significantly decreased, not normalized, but at very low values. Since these data, even in the absence of clinical symptoms, might have been indicative for adrenal insufficiency, a corticotropin-releasing hormone test was performed in 2 patients. After injection of 100 micrograms of human corticotropin-releasing hormone. ACTH and cortisol concentrations increased sufficiently. In conclusion, even though low hormonal concentrations were observed in pain patients during morphine treatment, pituitary and adrenal stimulation of the endocrine axis remained intact.


Assuntos
Analgésicos Opioides/farmacologia , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Morfina/farmacologia , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Administração Oral , Adulto , Idoso , Analgésicos Opioides/administração & dosagem , Estudos de Casos e Controles , Hormônio Liberador da Corticotropina/sangue , Preparações de Ação Retardada , Feminino , Humanos , Hidrocortisona/sangue , Masculino , Pessoa de Meia-Idade , Morfina/administração & dosagem
16.
Methods Find Exp Clin Pharmacol ; 18(3): 159-65, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8738066

RESUMO

Opioids have been reported in the literature to have immunosuppressive properties. Thus, we investigated the influence of morphine, morphine-3-glucuronide and morphine-6-glucuronide in vitro on phytohemagglutinin-stimulated proliferation of peripheral mononuclear cells from healthy humans. Furthermore, the effects of a 1-week treatment with morphine in a range of 30-240 mg/day on proliferation of lymphocytes from patients with chronic pain syndromes were evaluated. In addition, human peripheral mononuclear cell membranes were tested for specific opioid radioligand binding. The results show that i) morphine and its main metabolites do not influence mitogen-induced T-cell proliferation, ii) treatment of patients with sustained release morphine for 1 week did not impair the lymphocyte proliferative response, and iii) no specific binding of mu-, delta- and kappa-radioligands could be demonstrated to membranes of peripheral lymphocytes obtained from healthy humans. These results do not indicate an impairment of phytohemagglutinin-induced T-cell proliferation during pain treatment with sustained release morphine.


Assuntos
Analgésicos Opioides/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Morfina/farmacologia , Fito-Hemaglutininas/farmacologia , Linfócitos T/efeitos dos fármacos , Analgésicos Opioides/sangue , Divisão Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Células Cultivadas , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Morfina/sangue , Derivados da Morfina/farmacologia , Ensaio Radioligante , Linfócitos T/fisiologia , Timidina/metabolismo , Trítio
17.
Appl Radiat Isot ; 68(7-8): 1217-20, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20071188

RESUMO

As part of a Cooperative Research Project (CRP) aimed at improving the state of radioactivity measurement in nuclear medicine, the International Atomic Energy Agency (IAEA) organized a comparison of (57)Co solutions among the participants of the project. The comparison solutions were prepared from a single master stock solution and distributed to the participating laboratories, who measured the activity concentration of the solution using either the laboratory's radionuclide activity calibrator or primary standardization methods. A total of 9 sets of results were received, with 5 laboratories reporting results of primary measurements, one reporting results of secondary measurements calibrated against primary standards, and three laboratories reporting values based on measurements in commercial re-entrant ionization chambers using manufacturer-recommended calibration figures. Most of the laboratories reporting primary standardizations also provided results from secondary standardizations. The Comparison Reference Value was calculated from the mean of the five primary standardizations and was found to be 35.54 MBq g(-1), with a standard deviation of the mean of 0.17 MBq g(-1). Degrees of equivalence were calculated for each reporting laboratory and demonstrated that equivalence to within about 4% could be achieved, even in the case of those laboratories that used instruments calibrated by third parties.


Assuntos
Radioisótopos de Cobalto/análise , Calibragem , Radioisótopos de Cobalto/normas , Cooperação Internacional , Medicina Nuclear/normas , Piridinas/normas , Padrões de Referência , Soluções , Tiazóis/normas , Pesos e Medidas
19.
Anaesthesist ; 52(9): 787-94, 2003 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-14504804

RESUMO

OBJECTIVE: Regional anaesthesia is recommended for caesarean section in obese women. With regard to this aspect anaesthesia practice in the obstetrics department of the University Hospital Kiel was evaluated retrospectively. METHODS: Data from 1,461 consecutive caesarean sections were evaluated. Pregnant women were subgrouped according to their prepartal body mass index (BMI). Statistics were performed by the chi(2)-test and the Wilcoxon and Mann-Whitney U-test, with a significance threshold of p<0.05. RESULTS: Of the pregnant women who underwent a caesarean section 27% were obese (BMI 30.0-34.9) and 15% were extremely obese (BMI > or =35). Spinal anaesthesia was performed most frequently in 47% with an uptrend in severely obese parturients. All other aspects investigated were independent of BMI. Vasoactive drugs were given less during general anaesthesia than in regional anaesthesia (3 vs. 54%). APGAR values were significantly better with regional anaesthesia, but perioperative complaints of distress were more common. Spinal anaesthesia was favoured by patients and staff in the postoperative survey ( p<0.001). CONCLUSION: Obesity is a common risk factor in caesarean section anaesthesia. Spinal anaesthesia can be recommended even for obese parturients.


Assuntos
Anestesia por Condução , Anestesia Obstétrica , Raquianestesia , Cesárea , Obesidade/complicações , Adulto , Anestesia por Condução/efeitos adversos , Anestesia Obstétrica/efeitos adversos , Raquianestesia/efeitos adversos , Índice de Apgar , Índice de Massa Corporal , Feminino , Hemodinâmica/fisiologia , Humanos , Recém-Nascido , Satisfação do Paciente , Gravidez , Resultado da Gravidez , Estudos Retrospectivos , Fatores de Risco
20.
Phytomedicine ; 3(4): 315-8, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23195187

RESUMO

Kanjang(®) tablets (standardized Andrographis paniculata extract) have proven effective in the initial treatment of commond cold and sinusitis. Kanjang(®) tablets is a herbal formula, which has been developed by the Swedish Herbal Institute in Gothenburg. The tablets have shown a beneficial effect with regards to the subjective experience of initial symptoms of common cold and uncomplicated sinusitis, as well as to the duration of the symptoms. The preparation has been used in the Nordic countries for more than 12 years, mainly for reducing symptoms of common cold and sinusitis, and shortening the duration of the symptoms. In this controlled, double-blind study performed as a pilot trial at the Health Center, Hallehälsan, during the autumn of 1992, conducted in 50 patients, both subjective symptoms as well as duration of the symptoms were significantly reduced. From the results evaluated it is quite clear that Kanjang(®) tablets decrease the subjective symptoms of common cold as well as shortening of the period of sick leave significantly.

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