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71.
Platelet-melanoma cell interaction is mediated by the glycoprotein IIb- IIIa complex 总被引:3,自引:0,他引:3
A human malignant melanoma cell line (M3Dau) was observed by electron microscopy to interact directly with human platelets and induced platelet aggregation. Fab fragments of a monoclonal antibody MoAb (LYP18), directed against the platelet glycoprotein (GP) IIb-IIIa complex, inhibited platelet-melanoma interactions and platelet-platelet aggregation. M3Dau melanoma cells bind LYP 18 and synthesize IIb-IIIa- like GPs. When the melanoma cells were preincubated with LYP 18, tumor- platelet interaction did not occur, suggesting that the interaction may be mediated by the IIb-IIIa-like GPs present on the melanoma cell surface. Glanzmann's thrombasthenic platelets, lacking GPIIb and IIIa, did not interact with melanoma cells, indicating that the platelet GPIIb-IIIa complex is also necessary for the platelet-melanoma cell interaction. This work demonstrates the importance of the IIb-IIIa-like GPs, present on M3Dau melanoma cells, in mediating tumor-platelet interactions. 相似文献
72.
Lack of correlation between serum lipoproteins and biliary cholesterol saturation in patients with gallstones 总被引:1,自引:0,他引:1
Dr. Jay W. Marks Patricia A. Cleary John J. Albers 《Digestive diseases and sciences》1984,29(12):1118-1122
It has been suggested that elevated serum lipoprotein cholesterol levels may be a determinant of biliary cholesterol saturation and cholesterol gallstone disease. The aim of this study was to correlate serum lipoprotein cholesterol and apolipoprotein levels with biliary cholesterol saturation in patients with gallstones who participated in the National Cooperative Gallstone Study. Baseline serum lipoprotein and biliary lipid levels were studied in 181 of these patients before they received treatment for dissolution of their gallstones. Neither low-or high-density lipoprotein cholesterol nor apolipoprotein levels correlated with biliary cholesterol saturation. This study, therefore, does not support the concept that serum lipoproteins are a determinant of biliary cholesterol saturation. It is possible, however, that a significant effect of lipoprotein levels is obscured by the greater effects of more important determinants of biliary cholesterol saturation.This project was funded by the National Institute of Arthritis, Metabolism and Digestive Diseases of the Department of Health and Human Services under contract N01-AM-3-2216 and N01-AM-0-2205. The contents of this publication do not necessarily reflect the views or policies of the department nor does the mention of trade names, commercial products, or organizations imply endorsement by the U.S. Government. 相似文献
73.
L. Albers S. Ziebarth R. von Kries 《Bundesgesundheitsblatt, Gesundheitsforschung, Gesundheitsschutz》2014,57(8):952-960
Background
Strategies to prevent primary headaches could be very beneficial, especially given that primary headaches can lead to the development of chronic headache. In order to establish headache prevention strategies, the modifiable risk factors for primary headaches need to be identified.Material and methods
A systematic literature search on the risk factors for primary headaches was conducted independently by two persons using the databases MEDLINE and Embase. Further inclusion criteria were observational studies in adult general populations or case-control studies, where the effect sizes were reported as odds ratios or where the odds ratios could be calculated from the given data.Results
In all, 24 studies were included in the analysis. There was a large amount of heterogeneity among the studies concerning headache acquisition, headache classification, and risk factors for headache development. Independent of headache trigger and definition of headache, the association between headache and the risk factor “stress” was very high: The meta-analysis shows an overall effect of 2.26 (odds ratio; 95?%-CI =?[1.79; 2.85]). Studies evaluating neck and shoulder pain also report a strong association with headache; however, these results could not be summarized in a meta-analysis. Equally, the overall effects of smoking and coffee consumption on headaches could not be verified because the effect sizes were rather small and predominantly noticeable only at higher doses.Conclusion
A strong association between headache and the risk factors stress and neck and shoulder pain was confirmed. The effect sizes of smoking and coffee consumption on headaches were rather small. 相似文献74.
Ian R Grubb Sarah W Beckham Michel Kazatchkine Ruth M Thomas Eliot R Albers Mauro Cabral Joep Lange Stefano Vella Manoj Kurian Chris Beyrer for the IAS Treatment for Key Affected Populations Working Group 《Journal of the International AIDS Society》2014,17(1)
Introduction
Scientific research has demonstrated the clinical benefits of earlier initiation of antiretroviral treatment (ART), and that ART can markedly reduce HIV transmission to sexual partners. Ensuring universal access to ART for those who need it has long been a core principle of the HIV response, and extending the benefits of ART to key populations is critical to increasing the impact of ART and the overall effectiveness of the HIV response. However, this can only be achieved through coordinated efforts to address political, social, legal and economic barriers that key populations face in accessing HIV services.Discussion
Recent analyses show that HIV prevalence levels among key populations are far higher than among the general population, and they experience a range of biological and behavioural factors, and social, legal and economic barriers that increase their vulnerability to HIV and have resulted in alarmingly low ART coverage. World Health Organization 2014 consolidated guidance on HIV among key populations offers the potential for increased access to ART by key populations, following the same principles as for the general adult population. However, it should not be assumed that key populations will achieve greater access to ART unless stigma, discrimination and punitive laws, policies and practices that limit access to ART and other HIV interventions in many countries are addressed.Conclusions
Rights-based approaches and investments in critical enablers, such as supportive legal and policy environments, are essential to enable wider access to ART and other HIV interventions for key populations. The primary objective of ART should always be to treat the person living with HIV; prevention is an important, additional benefit. ART should be provided only with informed consent. The preventive benefits of treatment must not be used as a pretext for failure to provide other necessary HIV programming for key populations, including comprehensive harm reduction and other prevention interventions tailored to meet the needs of key populations. An end to AIDS is only possible if we overcome the barriers of criminalization, stigma and discrimination that remain key drivers of the HIV epidemics among key populations. 相似文献75.
LL Patton 《Oral diseases》2014,20(3):223-225
Over the last 30 years, there have been significant advances in our scientific knowledge of HIV disease, including prevention, detection, medical management, and attempts at cure. Investigations and observations of the oral cavity in individuals with HIV disease have contributed substantially to scientific discovery and innovation. Challenges remain for managing existing and emerging oral diseases associated with HIV and understanding the contribution of latent oral mucosal reservoirs to HIV eradication. 相似文献
76.
Erik L. Frandsen Jessica Otero Joe C. Rutledge Mariska S. Kemna Erin L. Albers Borah J. Hong Yuk M. Law Joshua M. Friedland‐Little 《Pediatric transplantation》2020,24(1)
Bortezomib is approved for the treatment of multiple myeloma but increasingly used in heart transplant (HTx) recipients with antibody‐mediated rejection (AMR). Severe pulmonary toxicity is a rare complication in multiple myeloma patients treated with bortezomib, but has not been described in a solid organ transplant recipient. A 20‐year‐old man 7 years post‐HTx presented with acute rejection with hemodynamic compromise. Endomyocardial biopsy showed mixed rejection (ISHLT grade 2R‐3R acute cellular rejection (ACR) and pAMR 1 (I+) with diffuse C4d staining). Two new high MFI circulating MHC class‐II donor‐specific antibodies (DSA) were detected. Treatment included corticosteroids, antithymocyte globulin, plasmapheresis, IVIG, rituximab, and bortezomib (1.3 mg/m2). Due to rebound in DSA, a second course of bortezomib was started. Thrombocytopenia and peripheral neuropathy prompted a 50% dose reduction during the 2nd course. Shortly after the 3rd reduced dose, the patient developed hypoxemic respiratory failure. Bronchoscopy revealed pulmonary hemorrhage with negative infectious studies. Chest CT showed bilateral parenchymal disease with bronchiectasis and alveolar bleeding. Despite treatment with high‐dose steroids, severe ARDS ensued with multisystem organ failure. The patient expired 23 days after the final dose of bortezomib. Post‐mortem lung histology revealed diffuse alveolar damage, pulmonary fibrosis, and hemorrhage. Cardiac histology showed resolving/residual ACR 1R and pAMR 1 (I+). While rare, bortezomib‐induced lung toxicity (BILT) can occur in HTx recipients and can carry a high risk of mortality. Drug reaction and immediate drug withdrawal should be considered in patients who develop respiratory symptoms, though optimal management of BILT is unclear. 相似文献
77.
Kirstin Albers Christian Schlein Kirsten Wenner Peter Lohse Alexander Bartelt Joerg Heeren René Santer Martin Merkel 《Atherosclerosis》2014
Deficiency of apoprotein A-V (apoA-V) can cause hypertriglyceridemia. In an 11 months old boy presenting with a severe hypertriglyceridemia, a formerly unknown 24 nucleotide deletion in exon 2 of the APOA5 gene was detected. The homozygous mutation results in an eight amino acid loss in the signal peptide sequence (c.16_39del; p.Ala6_Ala13del). Screening of control persons proved that this deletion is a rare mutation. Hypertriglyceridemia in the patient was only found at the time when he was breast fed, while after weaning, triglyceride levels were close to normal. Under both dietary conditions, apoA-V protein was undetectable in plasma while post-heparin plasma lipoprotein lipase activity was normal. 相似文献
78.
Lars Schimmöller Michael Quentin Christian Arsov Andreas Hiester Christian Buchbender Robert Rabenalt Peter Albers Gerald Antoch Dirk Blondin 《European radiology》2014,24(10):2582-2589
Purpose
This study evaluated the accuracy of MR sequences [T2-, diffusion-weighted, and dynamic contrast-enhanced (T2WI, DWI, and DCE) imaging] at 3T, based on the European Society of Urogenital Radiology (ESUR) scoring system [Prostate Imaging Reporting and Data System (PI-RADS)] using MR-guided in-bore prostate biopsies as reference standard.Methods
In 235 consecutive patients [aged 65.7?±?7.9 years; median prostate-specific antigen (PSA) 8 ng/ml] with multiparametric prostate MRI (mp-MRI), 566 lesions were scored according to PI-RADS. Histology of all lesions was obtained by targeted MR-guided in-bore biopsy.Results
In 200 lesions, biopsy revealed prostate cancer (PCa). The area under the curve (AUC) for cancer detection was 0.70 (T2WI), 0.80 (DWI), and 0.74 (DCE). A combination of T2WI + DWI, T2WI + DCE, and DWI + DCE achieved an AUC of 0.81, 0.78, and 0.79. A summed PI-RADS score of T2WI + DWI + DCE achieved an AUC of 0.81. For higher grade PCa (primary Gleason pattern?≥?4), the AUC was 0.85 for T2WI + DWI, 0.84 for T2WI + DCE, 0.86 for DWI + DCE, and 0.87 for T2WI + DWI + DCE. The AUC for T2WI + DWI + DCE for transitional-zone PCa was 0.73, and for the peripheral zone 0.88. Regarding higher-grade PCa, AUC for transitional-zone PCa was 0.88, and for peripheral zone 0.96.Conclusion
The combination of T2WI + DWI + DCE achieved the highest test accuracy, especially in patients with higher-grade PCa. The use of ≤2 MR sequences led to lower AUC in higher-grade and peripheral-zone cancers.Key Points
? T2WI + DWI + DCE achieved the highest accuracy in patients with higher grade PCa ? T2WI + DWI + DCE was more accurate for peripheral- than for transitional-zone PCa ? DCE increased PCa detection accuracy in the peripheral zone ? DWI was the leading sequence in the transitional zone 相似文献79.
Effect of transforming growth factor-beta 1 on proliferation and induction of hemoglobin accumulation in K-562 cells 总被引:1,自引:1,他引:1
The effects of transforming growth factor-beta 1 (TGF-beta 1) on proliferation and hemoglobinization in K-562 cells, a human multipotential hematopoietic cell line, were studied. We found that TGF- beta 1 could induce hemoglobin accumulation in K-562 cells. Various clones were selected on the basis of the inducibility of hemoglobinization by TGF-beta 1. One high response clone (no. 1) and one low response clone (no. 8) were studied in detail. Hemoglobin accumulation peaked on day 5 of culture in the presence of TGF-beta 1 (0.5 ng/mL, 20 pmol/L), when 90% of clone 1 cells, 55% of parent line cells, and less than 10% of clone 8 cells contained hemoglobin. There was a concomitant reduction in proliferation of 60% for clone 1, 40% for the parent line, and 30% for the clone 8 on day 5 of culture. Quantitative analysis showed that the hemoglobin contents in clone 1 after 5-day induction by TGF-beta 1 and hemin were 1.0 pg/cell and 2.9 pg/cell, respectively. The hemoglobin induced by TGF-beta 1 showed the same electrophoretic characteristics as the hemoglobin induced by hemin. The expression of epsilon-globin mRNA was minimally detectable in control cells and was induced in both TGF-beta 1 and hemin treated cells. Other cytokines with potential effects on K-562 cell proliferation and differentiation were also studied. Interleukin-1, interleukin-3, interferon alpha, interferon gamma, and inhibin, tested as single agents, showed minimal effects on proliferation. None of these agents could induce hemoglobinization or inhibit the hemoglobinization induced by TGF-beta 1. 相似文献