bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mesangial matrix‐activated mononuclear cells express functional scavenger receptors and accumulate intracellular lipid
Authors: Rahman Enam , Chana Ravinder S. , Ruan Xiong Z. , Powis Stephen H. , Varghese Zac , Wheeler David C. 
Published: September 2009

Introduction  Monocyte recruitment into the mesangium and foam cell formation are recognized features of glomerular injury. External signals encountered by these infiltrating cells may determine their behaviour and thereby potentially influence disease outcomes. Our previous studies indicate that activation of monocytes by mesangial matrix stimulates the production of a variety of mediators including inflammatory cytokines and matrix degrading enzymes.Methods  Using expression of peroxisome proliferator activator receptor‐γ (PPAR‐γ) and scavenger receptor (ScR) as differentiation markers, we examined whether matrix activation was associated with the expression of monocyte characteristics usually associated with a macrophage phenotype. THP‐1 mononuclear cells were incubated for 7 days with 500 µg/ml solublized matrix extracted from cultured human mesangial cells.Results  Using phorbol methyl ester (PMA) (125 nm) and albumin (500 µg/ml) as positive and negative controls, respectively, we demonstrated that matrix activation of monocytes led to intracellular lipid accumulation as demonstrated by oil red O staining. Matrix activation was also associated with a concentration‐dependent increase in the expression of both ScR and PPAR‐γ mRNA and a corresponding increase in PPAR‐γ protein expression on Western blotting. The presence of functional ScR was confirmed using FACS analysis in which incubation of matrix‐activated monocytes with Dil‐labelled acetylated low‐density lipoprotein (LDL) led to an increase in mean fluorescent intensity of 373% (P < 0.001) as compared to albumin (100%) and PMA (423%). This could be inhibited by addition of excess unlabelled ligand, suggesting specific binding to the ScR. Furthermore, incubation of LDL with mesangial matrix in the absence of cells led to enhanced electrophoretic mobility of recovered lipoprotein on agarose gel. A similar shift was seen when LDL was incubated with Cu2+, a powerful lipoprotein oxidant.Discussion  These results demonstrate that interactions with mesangial matrix induce expression of monocyte characteristics associated with a macrophage phenotype and promote oxidation of LDL, thereby converting it to an ScR ligand. Such observations may help to explain foam cell formation in the mesangium in the context of glomerular disease.
Domain deletions outside of the catalytic domain of drosophila tolloid result in loss of protease activity
Authors: Canty E.G. , Kadler K.E. 
Published: September 2009

Introduction  The tolloid (TLD)‐related zinc metalloproteinases serve multiple functions in development, being involved in both extracellular matrix assembly and TGF‐β signalling. Signalling by bone morphogenetic proteins BMPs, which form a subgroup of the TGF‐β superfamily, is a highly regulated process which involves cleavage of extracellular BMP antagonists by TLD‐like (TLL) proteases. In vertebrates, BMP‐1 and mTLL‐1 cleave the BMP antagonist chordin to release free BMPs, while in invertebrates, TLD cleaves the BMP antagonist short gastrulation (SOG) to release decapentaplegic (DPP). Mammalian TLD (mTLD), TLL‐1 and TLL‐2 share the same domain structure as drosophila TLD, while BMP‐1 is a shorter splice variant of mTLD which lacks the EGF‐2, CUB‐4 and CUB‐5 domains.Material and methods  Site‐directed mutagenesis was used to produce TLD constructs lacking various domains. These were subcloned into the vector pAc5.1V5His, along with wild‐type TLD and full‐length SOG. Transient transfections in drosophila S2 cells were used to produce recombinant proteins, and aliquots of medium containing the appropriate recombinant proteins were dialysed or desalted as required. In vitro digests of SOG by TLD and the TLD mutants were performed overnight at 25°C in the presence of recombinant DPP (R & D Systems). Digests were analysed by SDS Page and Western blotting, and full‐length SOG and SOG fragments were detected using an anti‐V5 antibody (Invitrogen).Results  Wild‐type TLD was able to cleave SOG at three distinct sites as previously reported (Marques et al. 1997). A ‘BMP1‐like’ TLD construct, truncated after the CUB3 domain, was efficiently secreted by S2 cells but was unable to cleave SOG. Wild‐type TLD was also found to have enhanced activity in the presence of calcium ions, indicating that it is a calcium‐dependent protease. Removal of the putative calcium‐binding domains from TLD (EGF1 and EGF2) resulted in a decreased amount of enzyme present in the medium of the transfected S2 cells and less (ΔEGF1) or abolished (ΔEGF2 and double deletion) protease activity.Discussion  These preliminary findings indicate that the EGF‐2, CUB‐4 and CUB‐5 domains are required for cleavage of SOG by TLD. This is in direct contrast to the cleavage of chordin which is actually cleaved most efficiently by the short‐splice variant BMP‐1 (Scott et al. 1999). In vitro cleavage of SOG also requires the presence of DPP, whereas chordin is cleaved in the absence of exogenous BMPs. It is possible that these domains could be involved in interactions with the substrate or alternatively with DPP itself. The putative calcium‐binding domains, EGF1 and EGF2, appear to be required both for secretion and stability of the protein as well as for protease activity. The mechanism whereby calcium augments the protease activity of TLD is unknown, but it could aid the binding of enzyme to substrate or create specific conformational changes in the enzyme to increase activity.
PRG‐4/SZP N‐ and C‐terminal domains: cloning, expression and characterization
Authors: Jones A.R.C. , Hughes C.E. , Wainwright S.D. , Flannery C.R. , Caterson B. 
Published: September 2009

Introduction  Proteoglycan‐4 (PRG‐4), also known as superficial zone protein/proteoglycan (SZP), is an approximately 345‐kDa mucinous proteoglycan that has been detected in a variety of tissues including cartilage, tendon, bone, heart and liver (Ikegawa et al. 2000). In the synovial joint, PRG‐4 is specifically synthesized by chondrocytes located in the superficial zone of articular cartilage and by some surface‐lining cells of the synovium (Schumacher et al. 1994). Sequence analyses have shown that the N‐ and C‐terminal vitronectin‐like domains of PRG‐4 may impart interesting functions relevant to synovial joint metabolism (Merberg et al. 1993; Flannery et al. 1999). The objective of this study was to investigate these potential functions, facilitated by the production of PRG‐4 N‐ and C‐terminal domains as recombinant proteins.Methods  cDNAs for the human N‐terminal (exons 2–5) and bovine C‐terminal (exons 7–12) domains of PRG‐4 were obtained by RT‐PCR and cloned into the expression vector pMT‐BiP for inducible, secreted expression in Drosophila S2 cells. Proteins were purified using FLAG‐M2 antibody affinity chromatography and visualized by SDS‐PAGE and Western blotting with PRG‐4‐specific antibodies. The heparin‐binding properties of recombinant proteins were investigated using heparin affinity chromatography. The interactions of recombinant PRG‐4 domains with human plasminogen activator‐inhibitor (PAI)‐1 and bovine type‐II collagen were assayed using standard ELISA techniques.Results  Stable cell lines have been generated that express human N‐terminal and bovine C‐terminal PRG‐4 domains. In both cases, two proteins have been purified, possibly due to a splice mechanism by the expression system. N‐terminal sequence data and Western blotting indicate that the two species in each case could represent full‐length and truncated proteins. Analyses of the two PRG‐4 N‐terminal domain species have confirmed the presence of a predicted heparin‐binding domain and indicate that the molecule can bind to PAI‐1, with binding activity localized towards its two somatomedin B domains. The somatomedin B domain of vitronectin is known to bind PAI‐1 (Seiffert 1997). Analyses of the two PRG‐4 C‐terminal species have demonstrated self‐association under nonreducing conditions and binding to heparin and PAI‐1.Discussion  The exact role of PRG‐4 in the synovial joint is yet to be elucidated. However, these results point towards the interaction of the N‐ and C‐terminal domains of PRG‐4 with structural molecules such as type‐II collagen and heparin, and functional molecules such as PAI‐1, a serpin that is involved in the fibrinolytic cascade and cell adhesion. These properties are in addition to the well‐documented boundary lubricating activity of the central mucinous region of PRG‐4.
Role of the EGF‐like domains in mammalian tolloid (mTLD) secretion and procollagen C‐proteinase activity
Authors: Garrigue‐Antar Laure , Kadler Karl E. 
Published: September 2009

Introduction  Bone morphogenetic protein (BMP)‐1 and its larger splice variant mammalian tolloid (mTLD) belong to the tolloid group of astacin‐like metalloproteinases that are fundamental to tissue patterning and extracellular matrix assembly. BMP‐1 and mTLD exhibit similar substrate specificity in vitro; however, BMP‐1 is a much better procollagen C‐proteinase than mTLD. mTLD consists of a prodomain (which is cleaved by a furin‐like enzyme) (Leighton & Kadler 2003), a zinc metalloproteinase domain and a C‐terminal part comprising five CUB domains thought to be important for protein–protein interactions (Hartigan et al. 2003), and two EGF‐like domains, which in other proteins are involved in calcium ion binding. BMP‐1 lacks the most C‐terminal two CUB domains and one EGF‐like domain. mTLD activity is known to be calcium ion dependent, as demonstrated for the chick homologue (Hojima et al. 1985). In our current work, we are studying the role of the EGF‐like domains in the secretion and procollagen C‐proteinase activity of mTLD, and the contribution that these domains made to calcium ion dependency.Materials and methods  We designed proteins lacking EGF1, EGF2 or both. NotI sites were introduced by PCR at the borders of the EGF domain of a cDNA clone encoding a V5‐His mTLD. Restriction enzyme digestion was used to delete individual domains. The mutant constructs in pCEP4 were stably transfected into 293‐EBNA cells. Expression was analysed by Western blot. The wild‐type and the mutant enzymes were purified on a nickel ion column, and their activity was determined by cleavage of type‐I procollagen in the presence or absence of 5 mm CaCl2.Results  We showed that (1) the mTLD proteins lacking EGF1, EGF2 or EGF1 + EGF2 were poorly secreted into the culture medium compared to mTLD and (2) the EGF deletion mutants remained calcium ion dependent, but some differences were seen. Most notably, the ΔEGF2 and ΔEGF1 + ΔEGF2 mutants were found to be better C‐proteinases than the wild‐type enzyme in the presence of calcium ions.Conclusion  From these preliminary data, we concluded that (1) the EGF domains are necessary for efficient secretion (2) both EGF1 and EGF2 domains contribute to the calcium ion dependency of mTLD and (3) the EGF2 domain might be a Ca2+‐activated hinge that ‘swings’ the CUB‐4 and CUB‐5 domains away from the active site. The ?EGF2 mTLD might be expected to have an open conformation, thereby making it a better C‐proteinase than the wild‐type enzyme, and (?4) Ca2+ ions are bound by other domains in mTLD and not only by the EGF‐like domains.
Age‐related changes in the glycosaminoglycans of human meniscal aggrecan
Authors: Al‐Jafary Meneerah , Huckerby Thomas N. , Lauder Robert M. 
Published: September 2009

Introduction  Meniscal damage and degradation, which are strongly correlated with subsequent OA, have been identified in approximately 60% of people over 60 years of age. Age‐related changes in articular cartilage glycosaminoglycans (GAGs) have been described, and used to facilitate the study of pathology‐related changes (Plass et al. 1998). However, such data do not yet exist for the meniscus.Materials and methods  Undamaged human menisci were obtained following leg amputations, and the vascular and avascular zones of each lateral and medial meniscus were extracted into 4 m GuHCl. Aggrecan was recovered in the A1 fraction following CsCl density gradient centrifugation, and the relative abundance of chondroitin, dermatan and keratan sulphates (CS, DS and KS) was examined by NMR spectroscopy at 400 MHz and 43 °C.Results  Human meniscal aggrecan was shown to contain CS, DS and KS, and our data show age‐related changes in the relative abundance of these GAGs. The change was similar for medial and lateral menisci and for the vascular and avascular zones within these.The KS abundance in aggrecan from young menisci (<15 years) was found to be 15–20% of the total GAGs. However, in older samples, it comprised only 7–12% of the GAGs.We have confirmed the presence of DS in human meniscal aggrecan and show that the abundance of DS gradually falls from approximately 16% at 10 years to 2–4% at 75 years. There is some variability between humans, although the trend is clear and for each human there is good agreement between medial and lateral menisci and vascular and avascular locations.The levels of CS comprise the remainder of the GAG attached to aggrecan and contribute the remainder of the GAG abundance. This can be seen to increase from 67 to 72% at 10 years to approximately 90% at 75 years.Discussion  Our data show a clear age‐related change in the relative abundance CS, DS and KS from human meniscal aggrecan. The data show a decrease in the abundance of KS and DS and a concomitant increase in CS levels. These observations differ from those widely seen for articular cartilage, in which the levels of CS are seen to fall with age.We have confirmed that DS is a component of human meniscal aggrecan in agreement with previous work (McNicol & Roughley 1980). However, previously reported levels of DS, approximately 20%, are those found only in younger menisci.Absolute levels of these GAGs have not yet been determined, and hence the mechanisms which bring about this relative increase in CS with age may include either changes in biosynthetic output and/or widespread GAG loss in which KS and DS loss increases with age.
Systematic review: endoscopic and imaging‐based techniques in the assessment of portal haemodynamics and the risk of variceal bleeding
Authors: SGOUROS S. N. , VASILIADIS K. V. , PEREIRA S. P. 
Published: September 2009

SummaryBackground  Invasive measurement of the hepatic venous pressure gradient (HVPG) is regarded as the gold standard for risk stratification and the evaluation of pharmaceutical agents in patients with portal hypertension.Aim  To review the techniques for endoscopic and imaging‐based assessment of portal haemodynamics, with particular emphasis on trials where the results were compared with HVPG or direct portal pressure measurement.Methods  Systematic search of the MEDLINE electronic database with keywords: portal hypertension, variceal bleeding, variceal pressure, endoscopic ultrasound, Doppler ultrasonography, magnetic resonance angiography, CT angiography, hepatic venous pressure gradient.Results  Computed tomography angiography and endoscopic ultrasound (EUS) have been both employed for the diagnosis of complications of portal hypertension and for the evaluation of the efficacy of endoscopic therapy. Colour Doppler ultrasonography and magnetic resonance angiography has given discrepant results. Endoscopic variceal pressure measurements either alone or combined with simultaneous EUS, correlate well with HVPG and risk of variceal bleeding and have a low interobserver variability.Conclusions  Endoscopic and imaging‐based measurements of portal haemodynamics provide an alternate means for the assessment of complications of portal hypertension. Further studies are required to validate their use in risk stratification and the evaluation of drug therapies in patients with portal hypertension.
The allogeneic graft‐versus‐cancer effect
Authors: Ringdén Olle , Karlsson Helen , Olsson Richard , Omazic Brigitta , Uhlin Michael 
Published: September 2009

SummaryAllogeneic haematological stem cell transplantation (HSCT) has developed into immunotherapy. Donor CD4+, CD8+and natural killer (NK) cells have been reported to mediate graft‐versus‐leukaemia (GVL) effects, using Fas‐dependent killing and perforin degranulation to eradicate malignant cells. Cytokines, such as interleukin‐2, interferon‐γ and tumour necrosis factor‐α potentiate the GVL effect. Post‐transplant adoptive therapy of cytotoxic T‐cells (CTL) against leukaemia‐specific antigens, minor histocompatibility antigens, or T‐cell receptor genes may constitute successful approaches to induce anti‐tumour effects. Clinically, a significant GVL effect is induced by chronic rather than acute graft‐versus‐host disease (GVHD). An anti‐tumour effect has also been reported for myeloma, lymphoma and solid tumours. Reduced intensity conditioning enables HSCT in older and disabled patients and relies on the graft‐versus‐tumour effect. Donor lymphocyte infusions promote the GVL effect and can be given as escalating doses with response monitored by minimal residual disease. A high CD34+cell dose of peripheral blood stem cells increases GVL. There is a balance between effective immunosuppression, low incidence of GVHD and relapse. For instance, T‐cell depletion of the graft increases the risk of relapse. This paper reviews the current knowledge in graft‐versus‐cancer effects. Future directions, such as immunotherapy using leukaemia‐specific CTLs, allo‐depleted T‐cells and suicide gene manipulated T‐cells, are presented.
Allergic sensitization is enhanced in early life through toll‐like receptor 7 activation
Authors: Phipps S. , Hansbro N. , Lam C. E. , Foo S. Y. , Matthaei K. I. , Foster P. S. 
Published: September 2009

SummaryBackground
Prospective cohort studies suggest that children hospitalized in early life with severe infections are significantly more likely to develop recurrent wheezing and asthma.Objective
Using an inhalational mouse model of allergic airways inflammation, we sought to determine the effect of viral and bacterial‐associated molecular patterns on the magnitude of the allergic inflammatory response and whether this effect was age dependent.Methods
BALB/c mice were sensitized by intranasal administration of endotoxinlow ovalbumin (OVA) in the absence or presence of viral single‐stranded (ss)RNA, lipoteichoic acid or flagellin as neonates (within the first 24 h of life) or as weanlings (4 weeks of age). Mice were challenged four times with OVA at 6 weeks of age and end‐points (bronchoalveolar lavage cytology, histology, antigen‐specific T and B cell responses) determined at 7 weeks of age.Results
Inhalational sensitization (<24 h or 4 weeks of age) and challenge with OVA induced a mild allergic inflammatory response in the airways as indicated by increased numbers of eosinophils and mucus cells, elevated serum OVA‐specific IgG1, and production of T helper 2 (Th2) cytokines. Mice sensitized to endotoxinlow OVA at birth in the presence of ssRNA or lipoteichoic acid, but not flagellin, showed an increase in the numbers of airway and tissue eosinophils, mucus producing cells and antigen‐specific production of IL‐13 as compared with mice exposed only to endotoxinlow OVA. By contrast, all three TLR ligands failed to increase the magnitude of OVA‐induced allergic inflammation in mice sensitized as weanlings.Conclusions
Recognition of distinct microbial‐associated patterns in early life may preferentially promote the de novo differentiation of bystander, antigen‐specific CD4+ T cells toward a Th2 phenotype, and promote an asthma‐like phenotype upon cognate antigen exposure in later life.
Reliability and validity of the caregiver quality of life index‐cancer (CQOLC) scale in Turkish cancer caregivers
Authors: Bektas Hicran A , Ozer Zeynep C 
Published: September 2009

Aims and objectives.  The aim of this study was to translate the Caregiver Quality of Life Index‐Cancer into Turkish and test the reliability and validity of the Turkish version of the Caregiver Quality of Life Index‐Cancer in Turkey.Background.  Cancer is a chronic illness that affects the entire family and deteriorates the quality of life of cancer caregivers. The Caregiver Quality of Life Index‐Cancer is a widely used instrument to measure quality of life in cancer caregivers. Therefore, identifying and increasing quality of life benefits of cancer caregivers.Design.  Methodological research design.Method.  This study describes the translation process of The Caregiver Quality of Life Index‐Cancer into Turkish and testing its reliability and validity on quality of life in cancer caregivers. The questionnaire was translated using a back‐translation technique. The statistical analysis was carried out using Cronbach’s alpha to test the internal consistency of the Caregiver Quality of Life Index‐Cancer scale while confirmatory and exploratory factor analyses were carried out using principal component analysis with varimax rotation and Kaiser Normalization to test its construct validity.Results.  The Cronbach’s alpha was found to be reliability for the total scale was 0·88 and subscale alpha coefficients ranged from 0·73–0·83. Confirmatory factor analysis resulted in four factor structure: burden, distruptiveness, positive adaptation and financial concerns.Conclusion.  The effects of providing care for patients with cancer on caregiver quality of life have not yet been adequately explored in Turkey. The results of this study suggest that the Turkish version of the Caregiver Quality of Life Index‐Cancer is a reliable and valid supplementary measure of the quality of life in cancer caregivers in Turkey.Relevance of clinical practice.  In research and practice, valid measurement instruments are needed to assess Quality of Life in Turkish cancer caregivers. The Caregiver Quality of Life Index‐Cancer scale is simple to administer and nurses by using this equipment in routine appointments will be able to better identify caregiver at risk for developing cancer related distress and worse Quality of Life.
Relationship between call light use and response time and inpatient falls in acute care settings
Authors: Tzeng Huey‐Ming , Yin Chang‐Yi 
Published: September 2009

Aims and objectives.  This exploratory study used archived hospital data to determine whether the call light use rate and the average call light response time contribute to the fall and the injurious fall rates in acute care settings.Background.  Inpatients often use call lights to seek nurses’ attention and assistance. Although implied in patient safety, no studies have examined data related to the call light use or the response time to call lights collected via existing tracking mechanisms to monitor nursing practice.Design.  The study was conducted in a Michigan community hospital and used archived hospital data for analyses for the period from February 2007–June 2008. The unit of analysis was unit‐week.Method.  The call light use rate per patient‐day was calculated based on information retrieved from the call light tracking system. The average response time in seconds was used as generated from the tracking system. The fall and injurious fall rates per 1000 patient‐days were calculated based on the fall incident reports. spss was used for data analyses. One‐way anova and correlation analyses were conducted.Results.  More calls for assistance related to less fall‐related patient harm. Surprisingly, longer response time to call lights also related to fewer total falls and less fall‐related patient harm. Generally speaking, more call light use related to longer response times.Conclusions.  This study’s findings challenged the appropriateness of targeting the goals of reducing the frequency of call light use and the fall rates as two outcome indicators of conducting hourly patient rounds.Relevance to clinical practice.  Encouraging call light use is a key to reducing injurious fall rates. Unit managers should routinely monitor the trend of the call light use rate and ensure that the call light use rate is maintained at least above the mean rate.