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1.
Penetration and distribution of three lipophilic probes in vitro in human skin focusing on the hair follicle. 总被引:2,自引:0,他引:2
Fluorescent model substances of increasing lipophilicity (Oregon Green) 488, Bodipy, FL C5 and Bodipy 564/570 C5) were selected to enable the visualization in the skin using confocal laser scanning microscopy. After measuring the penetration for 18 h, the nonfixed human scalp skin was imaged from the bottom parallel to the stratum corneum and in a cross-section view perpendicular to the skin surface. The images were evaluated by calculating relative accumulation values for different penetrants. The studies indicate that the penetrated amount is highest for Bodipy FL C5 (medium lipophilicity) and lowest for Bodipy 564/570 C5 (high lipophilicity) whereas Bodipy 564/570 C5 (high lipophilicity) reveals the highest relative accumulation in parts of the hair follicle compared to Oregon Green 488 (low lipophilicity). The addition of 30% (v/v) ethanol to the donor phase of substance with a low lipophilicity increases the follicular delivery. From our results we conclude that delivery to the hair follicle can be improved by increasing the drugs lipophilicity and optimizing the composition of the donor phase. However, no conclusion can be drawn about the actual route of transport to the hair follicle. 相似文献
2.
OBJECTIVE: This review examines acute and chronic whiplash-associated disorders to facilitate assessment, treatment and rehabilitation for further research and evidence-based practices. DESIGN: A review of the literature. RESULTS AND CONCLUSION: Whiplash-associated disorders account for a large proportion of the overall impairment and disability caused by traffic injuries. Rarely can a definite injury be determined in the acute (or chronic) phase. Crash-related factors have been identified, and several trauma mechanisms possibly causing different injuries have been described. Most whiplash trauma will not cause injury, and the majority of patients (92-95%) will return to work. Litigation is not a major factor. Cognitive impairments are not the same as brain injury. Variables such as pain intensity, restricted motion, neurological symptoms and signs, together with central nervous system symptoms can be used to predict a situation with risk of remaining complaints. Influences of other factors--the same as for other chronic pain conditions--also exist. Persistent/chronic pain is not merely acute pain that persists over time; changes occur at different levels of the pain transmission system. Chronic whiplash-associated disorders are associated with problems concerning social functioning, daily anxieties and satisfaction with different aspects of life. Adequate information, advice and pain medication together with active interventions might be more effective in the acute stage. Early multidisciplinary rehabilitation focusing on cognitive-behavioural changes might be of value. To develop specific treatment and rehabilitation, it is important to identify homogenous subgroups. 相似文献
3.
D Stiller P Herrmann H J Holzhausen 《Zentralblatt für allgemeine Pathologie und pathologische Anatomie》1983,128(5-6):307-316
In rare cases an utmost uncommonly pigmented lesion is found in young infants which is mostly located in the anterior maxilla. The histogenesis of this unusual soft tissue tumor has provoked a long-lasting debate, which is reflected in many synonyms. There is no anatomical precursor and the possibility of a phylogenetic ancestral form is discussed. Therefore, the term melanotic progonoma was proposed. Because of the derivation from neural crest cells the designation melanotic neuroectodermal tumor of infancy was introduced. This name is now generally accepted. In this study, two typical cases of this rare tumor are described. The tumors are composed of large epithelial-like melanin-producing cells and small nonpigmented cells, so-called lymphocyte- like cells resembling neuroblasts. The diagnostic relevant histological pattern is characterized by intensely pigmented cells arranged either in strands or clusters often forming the lining of small cleft-like or tubular spaces, or by alveolar structures surrounded by a fibrovascular stromal component. At ultrastructural level, the pigment corresponds to the cutaneous type of neural crest type of melanin. The histogenesis of these lesions and the classification of pigmented benign and malignant neuroectodermal tumors of the soft tissues are discussed especially taking into consideration the concept of the soft tissue variant of melanomas. The melanotic neuroectodermal tumor of infancy is a benign growth Only in very few cases a fatal outcome is reported in the literature. The melanotic neuroectodermal tumor of infancy must be distinguished from other types of benign and malignant neuroectodermal tumors. From histological point of view and with regard to its biological behaviour this lesion is a particular entity of pigmented neuroectodermal tumors of the soft tissues, and for subclassification the term melanotic progonoma should be maintained, too. 相似文献
4.
Hannelore Schmidt Frank Bartel Matthias Kappler Peter Würl Heidemarie Lange Matthias Bache Hans-Jürgen Holzhausen Helge Taubert 《Modern pathology》2005,18(5):638-644
Liposarcomas are a phenotypical heterogeneous group of tumors divided into four main subtypes: well-differentiated, dedifferentiated, myxoid/round cell, and pleomorphic. The aim of this study was to compare DNA sequence copy number changes of these subtypes as investigated by comparative genomic hybridization in 36 patients. Comparative genomic hybridization revealed genomic imbalances in tumors of 27 patients (mean 5.6 imbalances per tumor). The most frequent gains were within single regions of 1q, 12q, and 13q. We found a significant correlation of poor overall survival and gain of 13q21 (P=0.0221), 13q22 (P=0.0341), 13q31 (P=0.0410), and 13q32 (P=0.0074). The univariate Cox regression analysis revealed an increased risk of tumor-related death for patients whose liposarcomas possess with gains of 13q21 and 13q32 simultaneously (P=0.010; RR=7.1; 95% CI 1.6-31.7). Furthermore, 12 high-level amplifications were found in tumors of seven patients. In four cases 12q14-q15 and in two cases 13q32-q33 were amplified. We identified in different liposarcoma subtypes characteristic genomic changes: Gains and high-level amplifications of 12q occurred in all 11 investigated well-differentiated liposarcomas, and these changes were often present simultaneously with gains of 1q (mean 5.5 changes). In the two dedifferentiated liposarcomas, gains of 1q in both liposarcomas, and a high-level amplification of 13q were striking. Only eight of the 17 patients with myxoid/round cell liposarcomas showed changes in DNA copy number (mean 3.4 imbalances). In four of these eight cases gains of 13q occurred. The six pleomorphic liposarcomas possessed the most frequent genomic imbalances (mean number 16.3) of all liposarcoma subtypes investigated. These imbalances were in almost all chromosomal regions detected predominantly as over-representations of chromosomes 1, 5p, 13q, and 22q. Summarizing, all subtypes but well-differentiated liposarcomas showed gains of 13q, which were associated with a poor prognosis. 相似文献
5.
6.
Karl-Henrik Gustavson Ylva Flodérus Sten Jagell Lennart Wetterberg Svante B. Ross 《Clinical genetics》1982,22(1):22-24
Catechol-O-methyltransferase (COMT) activity in erythrocytes was measured in six children with Down's syndrome and in their parents to determine if COMT activity is related to a gene on chromosome 21. A gene dosage effect was a possible explanation of the COMT value in three of the children but not in the other three. 相似文献
7.
Appearance and Persistence of Antibodies Against Different Virus Components After Regular Measles Infections 总被引:13,自引:5,他引:13
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Different measles virus-specific antibody activities in acute, early (11 to 40 days after rash) and late (4 to 20 years postinfection) convalescent sera and gamma globulin were determined. Early immunoglobulin G antibodies gave a poor neutralization, which was increased 10- to 60-fold by addition of anti-gamma globulin.There was a high degree of correlation between titers of hemolysis-inhibiting (HLI) and hemagglutinating-inhibiting (HI) antibodies. However, in one out of fifteen late convalescent sera an HLI antibody titer of 640 in the presence of titer of only 20 in HI tests with Tween 80-either-treated antigen was found. Similar findings were made with sera from two patients with multiple sclerosis included in a parallel study. A somewhat higher titer of HI antibodies was demonstrable in these three sera when untreated material was used as antigen. These findings are interpreted in the following way. Antibodies against the hemagglutinin can block not only virus-specific agglutination but also lysis of red cells. In contrast, antibodies against the hemolysin, besides blocking the biological activity of this component, carry only a slight HI activity. This HI activity can be detected only by use of antigen preparations containing hemagglutinin-associated hemolysin.Complement-fixation (CF) and immunodiffusion tests (the latter were carried out with antigen preparations treated with 0.25% sodium dodecyl sulfate) demonstrated that, in almost all cases, antibodies against nucleocapsid structures dominated quantitatively among antibodies appearing in connection with and persisting after regular measles infections. Generally, only low titers of antibodies reacting with purified small particle hemagglutinin (HA; 10 to 14S) or additional structural or nonstructural components were identified in CF and immunodiffusion tests. 相似文献
8.
Lotte Höffner Jens Jung Nielsen Henning Langberg Ylva Hellsten 《The Journal of physiology》2003,550(1):217-225
In the present study we examined whether exercise and prostanoids have an effect on the muscle interstitial concentration of vascular endothelial growth factor (VEGF) and on the proliferative effect of muscle interstitial fluid. Dialysate from resting and exercising human skeletal muscle, obtained either during control conditions or during cyclooxygenase inhibition, was examined for its content of VEGF and for its effect on endothelial cell proliferation. Microdialysis probes with high (960 kDa) and low (5 kDa) molecular-mass cut-off membranes were placed in the vastus lateralis muscle of healthy young males. The subjects performed one-legged knee extensions (20 W). The concentration of VEGF in the 960 kDa dialysate was greater ( P < 0.05 ) during exercise compared to at rest (67 ± 28 vs. 230 ± 22 pg ml−1 ). The rate of endothelial cell proliferation was 2.7-fold higher ( P < 0.05 ) with the 960 kDa dialysate from resting muscle than with perfusate and was 5.8-fold higher ( P < 0.05 ) than the perfusate value with dialysate from exercising muscle. VEGF was not enhanced with exercise in the 5 kDa dialysate, yet the exercise dialysate induced a 1.9-fold higher ( P < 0.05 ) proliferation than the resting dialysate. Cyclooxygenase inhibition did not affect the VEGF concentration or the proliferating effect of the dialysates ( P > 0.05 ). This study demonstrates for the first time that VEGF is present in the interstitium of human skeletal muscle and that exercise enhances the interstitial concentration of VEGF and of other, as yet unidentified, angiogenic compounds. Products of cyclooxygenase do not appear to have an effect on the release of VEGF or other proliferative agents in human skeletal muscle. 相似文献
9.
Susanna Jernelöv Erik Forsell Henrietta Westman Ylva Eriksson Dufva Nils Lindefors Viktor Kaldo Martin Kraepelien 《Journal of sleep research》2023,32(2):e13759
Cognitive behavioural therapy for insomnia is efficacious and recommended for insomnia, but availability is scarce. Cognitive behavioural therapy for insomnia self-help interventions could increase availability, especially if unguided. Optimizing cognitive behavioural therapy for insomnia methods and system user-friendliness, we developed a short, digital, self-help programme—FastAsleep—based on the behavioural components of sleep restriction and stimulus control. This study investigated its feasibility and preliminary effects. Thirty media-recruited participants with moderate to severe insomnia were assessed via telephone before using FastAsleep for 4 weeks, and were interviewed afterwards. Self-ratings with web questionnaires were conducted at screening, pre-, mid- and post-treatment, and at 3-month follow-up. Primary outcomes were feasibility (credibility, adherence, system user-friendliness and adverse effects), and secondary outcomes were changes in symptom severity (insomnia, depression and anxiety). Adherence was generally high, participants' feasibility ratings were favourable, and adverse effects matched previously reported levels for cognitive behavioural therapy for insomnia. Symptoms of insomnia decreased after the treatment period (Hedge's g = 1.79, 95% confidence interval = 1.20–2.39), as did symptoms of depression and anxiety. FastAsleep can be considered feasible and promising for alleviating insomnia symptoms among patients fit for self-care. Future controlled trials are needed to establish the efficacy of FastAsleep and its suitability in a stepped care model. 相似文献
10.
We report on a 12-year old boy suffering from malignant epithelioid hemangioendothelioma of the liver, which is a very rare tumor in childhood. The tumor was detected by ultrasound examination at the age of 10 and appeared at that time as a solitary intrahepatic nodular lesion. During the following 2 years multiple nodular lesions developed in both hepatic lobes. There were neither any suspect anamnestic findings nor abnormal clinical or laboratory data. The tumor showed the typical histomorphological, immunohistochemical, and ultrastructural features of this entity, which is usually seen in older patients. We investigated proliferative activity, apoptotic regulation, and expression of VEGF and VEGF-receptor flk-1 by means of immunohistochemical techniques. According to the known slow growth activity of these tumors we found only a few Ki-67 positive tumor cells. We did not detect any apoptotic cells using TUNEL technique. The positive immunoreaction of the tumor cells with antibodies against VEGF and VEGF-receptor flk-1 may indicate the regulation of tumor growth by angiogenetic factors. We present our findings together with a summary of the most important publications of recent years concerning these tumors. 相似文献