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1.
Mariagrazia Marucci Gert Ragnarsson Anders Axelsson 《Journal of controlled release》2006,114(3):369-380
In this work, Electronic Speckle Pattern Interferometry (ESPI) is presented as a non-invasive tool to study drug transport in controlled release systems. ESPI is shown to be a feasible tool to measure drug film permeability via comparison with an ordinary diaphragm cell. A specially designed cuvette was used in the release study: the polymeric film separated the donor and the receiving chambers of the cuvette to create a diffusion cell with no mixing in the two chambers. Thus, the cuvette mimicked a coated system immersed in a stagnant bulk liquid. Concentration profile data were obtained for the two compartments. Using these data, it was possible to visually discriminate between a film subject only to diffusion and a film subject to diffusion as well as osmotic effects. Moreover, using the concentration profile data collected at different time intervals, it was possible to follow the film properties in terms of drug permeability, thus studying how drug permeability depended on drug concentration. Compared to other measuring techniques, ESPI offers the advantages that no invasive measurements are needed, and that no sampling and calibration are required. Furthermore, the permeability can be measured with no influence of mass transfer in the boundary layers. 相似文献
2.
Comparison of ThinPrep versus conventional smear cytopreparatory techniques for fine-needle aspiration specimens of head and neck masses. 总被引:2,自引:0,他引:2
Lloyd Ford Barry M Rasgon Raymond L Hilsinger Raul M Cruz Karen Axelsson Gregory J Rumore Thomas M Schmidtknecht Balaram Puligandla John Sawicki William Pshea 《Otolaryngology--head and neck surgery》2002,126(5):554-561
OBJECTIVES: Diagnostic accuracy of the ThinPrep process (Cytyc, Boxborough, MA) was compared with that of conventional (smear) cytopreparation for fine-needle aspiration (FNA) of head and neck masses. METHODS: In a prospective, randomized, single-blinded study, 209 patients served as their own controls and underwent 236 FNAs using ThinPrep and conventional (smear) cytopreparatory techniques. RESULTS: ThinPrep produced less air-drying artifact and less mechanical distortion than the conventional method. The conventional technique was diagnostic in 63% of samples; the ThinPrep technique was diagnostic in 55% of samples. When all results were combined, pathologists subjectively preferred the conventional technique but accepted use of ThinPrep as the only cytopreparatory technique for most head and neck masses. CONCLUSIONS: For adequately experienced cytopathologists, ThinPrep is acceptable for FNA of salivary masses, neck cysts, metastatic lymph nodes, and thyroid lesions. Conventional smear technique should be used for FNA of nonmetastatic lymphoid lesions. Use of ThinPrep can complement use of the conventional (smear) cytopreparatory technique when aspirate is nondiagnostic or bloody, when the patient has a blood-borne infectious disease, when the clinician is inexperienced, or when aspirate has entered the syringe. 相似文献
3.
To determine the influence of the duration of postoperative lumbar immobilization with the aid of a rigid lumbar orthosis on the consolidation of posterolateral lumbosacral fusions, 22 patients with no previous osseous spinal surgery and with fusion without osteosynthesis due to spondylolysis-olisthesis Grade 1 to 2 or intervertebral disc or facet joint disorder were examined by roentgen stereophotogrammetric analysis in supine and erect positions and by conventional radiography for 1 year after surgery. In Series 1, patients (n = 11) were instructed to keep the trunk straight with the aid of a molded, rigid lumbar orthosis for 5 months after surgery; and in Series 2 (n = 11), the same instructions were given, but for 3 months. In Series 1, osseous fusion was seen on radiographs in eight patients. In these patients, the intervertebral translations between the fused vertebrae began to decrease 3-6 months after surgery, and within 1 year, the fusions became rigid, as defined by roentgen stereophotogrammetric analysis, or intervertebral translations of mostly less than 1 mm persisted. In three patients with poor fusion still seen on radiographs 1 year after surgery, no rigid fusion was obtained and intervertebral translations of up to 10 mm persisted. In Series 2, a similar roentgen stereophotogrammetric analysis pattern was noted in two patients with osseous fusion and in seven with poor fusion seen on radiographs. The fusion was radiographically doubtful in two patients. In these patients, the intervertebral translations decreased, but translations of 1.5 mm persisted 1 year after surgery.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
4.
Patric M Schiltz German G Gomez Susana B Read Nisha V Kulprathipanja Carol A Kruse 《Journal of interferon & cytokine research》2002,22(12):1209-1216
To enhance the efficacy of cellular immunotherapy for gliomas, we tested the concept of using proinflammatory cytokine treatment with interferon-gamma (IFN-gamma) or interleukin-1beta (IL-1beta) or both to render glioma cells more susceptible to cytolysis by alloreactive cytotoxic T lymphocytes (aCTL). The cytokines, separately or in combination, were able to upregulate major histocompatibility complex (MHC) class I antigen or intercellular adhesion molecule-1 (ICAM-1) on Fischer rat 9L gliosarcoma cells. 9L cells were incubated in vitro for 24, 48, or 72 h with varying concentrations of rat IFN-gamma (0-2000 U/ml) or recombinant human IL-1 (rHUIL-1) (0-1000 U/ml) or both. By 48 h, IFN-gamma (500 U/ml) maximally induced the percentage of positive expressing cells and the relative antigen density of MHC class I and ICAM-1 on 9L cells, whereas IL-1 induced only ICAM-1 expression. Simultaneous incubation of IL-1 with IFN-gamma did not further affect the induction of class I on 9L cells more than that achieved with IFN-gamma alone. 9L cells with upregulated MHC class I and ICAM-1 expression were more sensitive to lysis by aCTL in in vitro cytotoxicity assays, regardless of whether the precursor aCTL came from naive or from 9L-immunized rats. Furthermore, inhibition of 9L cytotoxicity in assays that included blocking antibodies to MHC class I or to ICAM-1 revealed that T cell receptor (TCR) interactions with MHC class I and that ICAM-1 interactions with lymphocyte function-associated-1 (LFA-1) antigen account for a portion of the glioma lysis by aCTL. 相似文献
5.
Effect of two preventive programs on oral health knowledge and habits among Brazilian schoolchildren
Yvonne A. P. Buischi Per Axelsson Luciene B. Oliveira Marcia P. A. Mayer Per Gjermo 《Community dentistry and oral epidemiology》1994,22(1):41-46
Abstract – The effect upon dental health knowledge and dental health behavior of a comprehensive and a less comprehensive preventive program was compared in a 3-yr follow up study. The comprehensive program included active participation of the students and parental involvement. The study group consisted of 186 Brazilian schoolchildren 13 yr of age at the start of the program. A reference group from another school of similar socioeconomic level was included in the analyses. The data were collected from questionnaires filled in by the children under surveillance after the completion of the program. Significant differences in knowledge as well as in reported behavior were observed. The children enrolled in the comprehensive program in general scored higher in dental health knowledge than did those in the less comprehensive program. However, the latter group of children seemed to have acquired more correct knowledge during the period than had the control and reference children. Similar results were obtained concerning reported dental health behavior. 相似文献
6.
Thirty-seven patients with major affective disorders according to DSM-III and on continuous lithium treatment were followed during a 7-year period. Outcome was assessed by use of the Comprehensive Psychopathological Rating Scale and by the need for additional psychotropic medication and for hospital and outpatient care. Anamnestic variables and patient's attitudes to their lithium medication were also included in the analysis of outcome, as were laboratory data, including lithium parameters. An increase in psychopathology was demonstrated in a significant number of patients and was attributed mainly to an increase in the depressive symptoms, with a significant increase in the rated scores for fatiguability, pessimistic thoughts, reduced sleep, and inner tension. Suicidal thoughts were common, but no suicide attempts were made. A significant number of patients complained of failing memory, but no significant progression was demonstrated during the 7-year study period. The increase in the depressive symptoms was closely correlated with the number of hospital admissions for depressive recurrence and with the number of days in hospital. The following factors showed a significant relationship with the increase in depressive symptoms: serum lithium levels, large increase in the elimination half-life of lithium, low level of social functioning, low TSH values, and need of concomitant administration of antidepressants and benzodiazepines. 相似文献
7.
Marie-Louise Dither-Centerlind Bernt Axelsson Sten Hammarstrom Ulla Hellstrm Peter Perlmann 《European journal of immunology》1980,10(6):434-442
The mode of interaction of twelve lectins with human T lymphocytes was investigated. In order to establish possible differences between mitogenic and nonmitogenic lectins, they were studied for their capacity to induce or inhibit DNA synthesis. Their interaction with intact T cells was studied by immunofluorescence and 51Cr release. Further, lectins conjugated to Sepharose were investigated with regard to their capacity to bind surface glycopeptides from T cell lysates. Operationally, the lectins could be divided into three groups: (a) mitogenic lectins; (b) lectins inhibitory for lymphocyte mitogenesis as induced by leucoagglutinin (La) from Phaseolus vulgaris; and (c) nonmitogenic lectins which were noninhibitory in this La system. Six lectins were nonmitogenic. For two or possibly three of these, lack of mitogenicity was due to complete or partial failure to bind to the lymphocytes. This explanation could not account for lack of mitogenicity of the other three nonmitogenic lectins. Only two of the lectins utilized inhibited La-induced mitogenesis. However, when the lectins were compared with regard to their capacity to bind surface glycopeptides from T cell lysates, important differences between mitogenic and nonmitogenic lectins were seen. As revealed by polyacrylamide gel electrophoresis in sodium dodecyl sulfate and autoradiography, the mitogenic lectins bound a larger number of surface glycopeptides (15–20) than the nonmitogenic lectins (3–10). More importantly, five distinct glycopeptides (gp 135 K, 125 K, 105 K, 95 K and 43 K) were bound by all mitogenic lectins but not by the nonmitogenic lectins. It remains to be established whether these glycopeptides are present on the T cells which are susceptible to the mitogenic action of the lectins and whether it is the interaction of the lectins with one or several of them which triggers mitogenicity. 相似文献
8.
S. E. Andersson L. Källström M. Malm A. Miller-Larsson B. Axelsson 《Inflammation research》1995,44(10):418-422
In the present study we have investigated the effect of L-nitro arginine mono methyl ester (L-NAME), an inhibitor of nitric oxide (NO) synthase on Sephadex induced inflammation in the rat lung. Instillation of Sephadex into the airways induced an inflammatory reaction characterized by a long-lasting interstitial oedema, measured as an increase in lung weight, and an influx of inflammatory cells into the airways. L-NAME given s.c. prevented the increase in lung weight following Sephadex instillation. The inactive enantiomer D-NAME had no effect, nor did aminoguanidine which indicates that this effect of L-NAME was mediated by inhibition of the constitutive form of NOS. Treatment with L-NAME did not reduce an established oedema. In contrast, L-NAME tended to enhance the influx of oesinophils into the airways of Sephadex-instilled animals.L-NAME did not have any effect on the development of oedema in adrenalectomized rats or in animals where formation of glucocorticosteroids (GCS) was inhibited with metyrapone. L-NAME did not however, increase plasma levels of corticosterone. The present results indicate that, in this model, inhibition of NO-synthesis has marked anti-inflammatory effects. The underlying mechanism is complex but seems not to involve prevention of overproduction of NO. 相似文献
9.
Verhell Coleta; de Graaff Graaff Esther; Bakker Cathy E.; Willemsen Rob; Willems Patric J.; Meijer Nicolle; Galjaard Hans; Reuser Arnold J.J.; Oostra Ben A.; Hoogeveen Andre 《Human molecular genetics》1995,4(5):895-901
FMR1 protein expression was studied in different tissues. Inhuman, monkey and murine tissues, high molecular mass FMR1 proteins(6780 kDa) are found, as shown in lymphobiastoid celiiines. The identity of these proteins was confirmed by theirabsence in tissues from patients with the fragile X syndromeand a FMR1 knock-out mouse. An IIe367Asn substitution in theFMR1 protein did not aiter the transiation, processing and localizationof FMR1 proteins in lymphoblastoid cells from a patient carryingthis mutation. All the high molecular mass FMR1 proteins isolatedfrom normal lymphoblastoid cells and cells from the patientwith the IIe367Asn substitution were able to bind RNA. However,the FMR1 proteins of the patient had reduced affinity for RNAbinding at high salt concentrations. In some human, monkey andmurine tissues low molecular mass FMR1 proteins (3941kDa) were found, which had the same N terminus as the 6790kDa isoforms, but differ in their C terminus and are thereforemost likely the result of carboxy-terminal proteolytic cleavage.These low molecular mass FMR1 proteins did not bind RNA, incontrast with the high molecular mass FMR1 proteins. The significanceof these low molecular mass proteins remains to be studied. 相似文献
10.
Johansson B Axelsson P Billström R Strömbeck B Arheden K Olofsson T Cervin A Adriansson M Tanke HJ Mitelman F Fioretos T 《Genes, chromosomes & cancer》2001,30(3):261-266
Three adult de novo acute myeloid leukemias (AML M1, M2, and M4) with an isochromosome 7p are presented. No additional abnormalities were detected by G-band and multicolor, using combined binary ratio labeling, fluorescence in situ hybridization (FISH) analyses, indicating that the i(7p) was the sole, i.e., the primary, chromosomal aberration. Although the patients were elderly--68, 72, and 78 years old--they all responded very well to chemotherapy, achieving complete remission lasting more than a year. Further FISH analyses, using painting, centromeric, as well as 7q11.2-specific YAC probes, revealed that the i(7p) contained two centromeres and that the breakpoints were located in 7q11.2. Thus, the abnormality should formally be designated idic(7)(q11.2). The detailed mapping disclosed a breakpoint heterogeneity, with the breaks in 7q11.2 varying among the cases, being at least 1,310 kb apart. Furthermore, the breakpoints also differed within one of the cases, being located on both the proximal and the distal side of the most centromeric probe used. Based on our three patients, as well as on a previously reported 82-year-old patient with AML M2 and idic(7)(q11) as the only chromosomal change, we suggest that this abnormality, as the sole anomaly, is associated with AML in elderly patients who display a good response to induction chemotherapy and, hence, have a favorable prognosis. Furthermore, the heterogeneous breakpoints in 7q11.2 suggest that the important functional outcome of the idic(7)(q11.2) is the genomic imbalance incurred, i.e., gain of 7p and loss of 7q material, rather than a rearrangement of a specific gene. 相似文献