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The exact mechanism by which cytotoxic ribonucleases reach the cytosol of tumor cells remains unclear. The interaction of ribonucleases with a lipid bilayer is involved in the translocation of ribonucleases across the endosomal membrane. Here, we aimed to study the hydropathy character of toxic antitumor ribonucleases (bovine seminal ribonuclease and binase) and two non-toxic ribonucleases (bovine pancreatic ribonuclease and human pancreatic ribonuclease) by sliding-window hydrophobicity analysis. Comparative hydropathy plot analysis of the non-toxic pancreatic ribonucleases and their toxic variants was also performed. The data obtained indicate that some cytotoxic ribonucleases have a hydrophobic segment, which is sterically available for the hydrophobic interaction with a tumor cell membrane and endosomal membrane. After dissociation, subunits of dimeric ribonucleases are probably capable of thermodynamically favorable interaction with the interfacial region of a lipid bilayer. Remarkably the hydrophobic segment is not identified in the amino acid sequences of non-toxic ribonucleases. The paper describes the hydrophobic properties of toxic RNases that are essential for both the model of a lipid–protein interaction and the cytotoxicity mechanism unraveling.  相似文献   
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Clinical Rheumatology - The aim was to evaluate patient satisfaction with virtual care, and identify factors associated with level of satisfaction. Surveys were mailed to all patients who had a...  相似文献   
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The accuracy of address coding and the effects of coding errors   总被引:1,自引:0,他引:1  
Studies that estimate the influence of characteristics of place on health often use geocoded addresses to identify location of study subjects. This study uses housing built before 1990 selected for the 1995-2001 National Health Interview Survey (N=252,421) to develop a standard against which geocodes obtained from an address-coding program are compared. The results show that geocoding is generally accurate and is more successful in urban areas. Blockgroups with missing codes are more rural and somewhat poorer than blockgroups with correct codes. The effect of incorrect codes on statistical analyses depends on the proportion rural in a study population.  相似文献   
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Developments in managing CF continue to drive dramatic improvements in survival. As newborn screening rolls-out across Europe, CF centres are increasingly caring for cohorts of patients who have minimal lung disease on diagnosis. With the introduction of mutation-specific therapies and the prospect of truly personalised medicine, patients have the potential to enjoy good quality of life in adulthood with ever-increasing life expectancy. The landmark Standards of Care published in 2005 set out what high quality CF care is and how it can be delivered throughout Europe. This underwent a fundamental re-write in 2014, resulting in three documents; center framework, quality management and best practice guidelines. This document is a revision of the latter, updating standards for best practice in key aspects of CF care, in the context of a fast-moving and dynamic field.In continuing to give a broad overview of the standards expected for newborn screening, diagnosis, preventative treatment of lung disease, nutrition, complications, transplant/end of life care and psychological support, this consensus on best practice is expected to prove useful to clinical teams both in countries where CF care is developing and those with established CF centres. The document is an ECFS product and endorsed by the CF Network in ERN LUNG and CF Europe.  相似文献   
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Intracoronary delivery of endothelial progenitor cells (EPCs) is an emerging concept for the treatment of cardiovascular disease. Enhancement of EPC adhesion to vascular endothelium could improve cell retention within targeted organs. Because extracellular adenosine is elevated at sites of ischemia and stimulates neovascularization, we examined the potential role of adenosine in augmenting EPC retention to cardiac microvascular endothelium. Stimulation of adenosine receptors in murine embryonic EPCs (eEPCs) and cardiac endothelial cells (cECs) rapidly, within minutes, increased eEPC adhesion to cECs under static and flow conditions. Similarly, adhesion of human adult culture-expanded EPCs to human cECs was increased by stimulation of adenosine receptors. Furthermore, adenosine increased eEPC retention in isolated mouse hearts perfused with eEPCs. We determined that eEPCs and cECs preferentially express functional A1 and A2B adenosine receptor subtypes, respectively, and that both subtypes are involved in the regulation of eEPC adhesion to cECs. We documented that the interaction between P-selectin and its ligand (P-selectin glycoprotein ligand-1) plays a role in adenosine-dependent eEPC adhesion to cECs and that stimulation of adenosine receptors in cECs induces rapid cell surface expression of P-selectin. Our results suggest a role for adenosine in vasculogenesis and its potential use to stimulate engraftment in cell-based therapies.  相似文献   
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Background

African Americans (AA) are a third as likely as Caucasians to become registered organ donors at the Department of Motorized Vehicles (DMV). The Department of Health and Human Services has set the goal that at least 50% of adults in each state are registered donors.

Aims

The purpose of this study was to explore the personal, behavioral and environmental factors associated with AA donor registration decision-making at the DMV.

Methods

Guided by the Social Cognitive Theory, 13 focus groups (n = 100 participants) were conducted with AAs within 3 months of visiting a DMV and making a decision regarding whether to become or to not become a registered donor. The data were analyzed using inductive thematic and qualitative content analyses.

Results

Study participants expressed a desire to learn more information while waiting in line at the DMV. Knowing a family member or friend in need of an organ transplant, and the desire to make one's own decision were two salient factors associated with the decision to become a registered organ donor. Several aspects of the DMV environment (e.g., noisy, overcrowded, lacking privacy) were cited as deterrents to becoming a registered donor.

Discussion

This study highlights the personal, behavioral and environmental factors associated with AA organ donor registration decision-making at the DMV.

Conclusion

The DMV is a setting where many adults make a decision about organ donation. Policies that create an environment in the DMV to support informed decision-making (e.g., privacy, informed clerks, available educational materials, etc.) are indicated.  相似文献   
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