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991.
Zhenhong Qu Cesar Hernandez Garcia Leslie M. O'Rourke Stephen R. Planck Manoj Kohli James T. Rosenbaum 《Arthritis \u0026amp; Rheumatology》1994,37(2):212-220
Objective. To test the hypothesis that local proliferation contributes significantly to the hyperplasia of rheumatoid synovium. Methods. Immunohistologic and chemical staining was used to identify 3 markers of cell proliferation: proliferating cell nuclear antigen, c-myc proto-oncogene, and nucleolar organizer regions. Synovium from 21 patients with rheumatoid arthritis, 34 with degenerative joint disease, and 7 with joint trauma was examined. Results. All 3 markers indicated substantial, active proliferation of synovial lining cells in synovium with hyperplasia. Proliferating cells showed type I procollagen immunoreactivity but were negative for CD68, a monocyte/macrophage marker. Proliferation was greater in rheumatoid arthritis than in the other conditions evaluated. Conclusion. In situ proliferation of fibroblast-like synoviocytes in the synovium lining contributes considerably to the increase in cell numbers in rheumatoid synovium. 相似文献
992.
Lorna Dunning Aditya R Gandhi Martina Penazzato Djra I Soeteman Paul Revill Simone Frank Andrew Phillips Caitlin Dugdale Elaine Abrams Milton C Weinstein MarieLouise Newell Intira J Collins Meg Doherty Lara Vojnov Patricia Fassinou Ekouvi Landon Myer Angela Mushavi Kenneth A Freedberg Andrea L Ciaranello 《Journal of the International AIDS Society》2021,24(1)
IntroductionUptake of early infant HIV diagnosis (EID) varies widely across sub‐Saharan African settings. We evaluated the potential clinical impact and cost‐effectiveness of universal maternal HIV screening at infant immunization visits, with referral to EID and maternal antiretroviral therapy (ART) initiation.MethodsUsing the CEPAC‐Pediatric model, we compared two strategies for infants born in 2017 in Côte d’Ivoire (CI), South Africa (SA), and Zimbabwe: (1) existing EID programmes offering six‐week nucleic acid testing (NAT) for infants with known HIV exposure (EID), and (2) EID plus universal maternal HIV screening at six‐week infant immunization visits, leading to referral for infant NAT and maternal ART initiation (screen‐and‐test). Model inputs included published Ivoirian/South African/Zimbabwean data: maternal HIV prevalence (4.8/30.8/16.1%), current uptake of EID (40/95/65%) and six‐week immunization attendance (99/74/94%). Referral rates for infant NAT and maternal ART initiation after screen‐and‐test were 80%. Costs included NAT ($24/infant), maternal screening ($10/mother–infant pair), ART ($5 to 31/month) and HIV care ($15 to 190/month). Model outcomes included mother‐to‐child transmission of HIV (MTCT) among HIV‐exposed infants, and life expectancy (LE) and mean lifetime per‐person costs for children with HIV (CWH) and all children born in 2017. We calculated incremental cost‐effectiveness ratios (ICERs) using discounted (3%/year) lifetime costs and LE for all children. We considered two cost‐effectiveness thresholds in each country: (1) the per‐capita GDP ($1720/6380/2150) per year‐of‐life saved (YLS), and (2) the CEPAC‐generated ICER of offering 2 versus 1 lifetime ART regimens (e.g. offering second‐line ART; $520/500/580/YLS).ResultsWith EID, projected six‐week MTCT was 9.3% (CI), 4.2% (SA) and 5.2% (Zimbabwe). Screen‐and‐test decreased total MTCT by 0.2% to 0.5%, improved LE by 2.0 to 3.5 years for CWH and 0.03 to 0.07 years for all children, and increased discounted costs by $17 to 22/child (all children). The ICER of screen‐and‐test compared to EID was $1340/YLS (CI), $650/YLS (SA) and $670/YLS (Zimbabwe), below the per‐capita GDP but above the ICER of 2 versus 1 lifetime ART regimens in all countries.ConclusionsUniversal maternal HIV screening at immunization visits with referral to EID and maternal ART initiation may reduce MTCT, improve paediatric LE, and be of comparable value to current HIV‐related interventions in high maternal HIV prevalence settings like SA and Zimbabwe. 相似文献
993.
Martina Lenzuni Giulia Suarato Dalila Miele Riccardo Carzino Marco Ruggeri Rosalia Bertorelli Giuseppina Sandri Athanassia Athanassiou 《RSC advances》2021,11(39):24345
Drug-eluting stents (DES) have been widely used for the treatment of cardiovascular diseases. Nevertheless, chronic inflammation and delayed re-endothelialization still represent challenges for their clinical use. In the present work, we developed novel bilayer coatings for stent applications that could overcome these limitations, exclusively using biodegradable plant-based drugs and polymers. In particular, stainless steel surfaces were coated with rutin-loaded zein (the active layer) and cross-linked alginate (the sacrificial layer) via facile dip and spray coating methods. Various mechanical tests and analysis tools, such as infrared spectroscopy, water contact angle measurements, and scanning electron microscopy were used to characterize the coated surfaces. Degradation and release studies of the films were extensively carried out and compared. The release rate of rutin from the bilayer coating reached 66.1 ± 3.2% within 24 hours of incubation (initial burst period), while the rest of the drug was released over 21 days in a sustained manner. Antioxidant assays confirmed that rutin retained its free radical scavenging ability after being eluted in phosphate buffer at 37 °C. In vitro results with human fibroblasts and endothelial cells suggested that the coating materials and their degradation products are highly biocompatible. In conclusion, our novel drug-eluting coatings, fabricated with natural biodegradable polymers, are promising materials for DES applications, allowing a sustained drug delivery and improving the biocompatibility of cardiovascular implanted devices.Zein-based biodegradable bilayer coatings were successfully prepared and characterized. Release profiles, antioxidant potential, and biocompatibility were investigated, aiming for more sustainable coatings for drug-eluting stents. 相似文献
994.
Afaf Oulmidi Smaail Radi Abderrazak Idir Abdelmajid Zyad Imad Kabach Mohamed Nhiri Koen Robeyns Aurelian Rotaru Yann Garcia 《RSC advances》2021,11(55):34742
The complexes: [CoL2](ClO4)2 (1), [FeL2](ClO4)2 (2), [NiL2](ClO4)2 (3) and [MnLCl2] (4), with L = diethyl-1,1′-(pyridine-2,6-diyl)bis(5-methyl-1H-pyrazole-3-carboxylate), were synthesized and fully characterized. Structural analysis revealed two distinct patterns influenced by the counter ions where L acts as a tridentate chelating ligand. The in vitro antitumor activity of L and L′ (diethyl 2,2′-(pyridine-2,6-diylbis(5-methyl-1H-pyrazole-3,1-diyl)) diacetate) as well as their metal complexes, was tested by the measurement of their cytostatic and cytotoxic properties towards the blood cancer mastocytoma cell line P815. We have also investigated their interactions with the antioxidant enzyme system. As a result, [MnL′Cl2] (1′) exhibited the strongest activity compared to reference cis-platin with no cytotoxicity towards normal cells PBMCs (Peripheral Blood Mononuclear Cells). On the other hand, the antioxidant enzyme activity showed that the efficiency of metal complex 1′ against P815 tumor cells was via the rise in the SOD activity and inhibition of CAT enzyme activity. This proof of concept study allows disclosure of a new class of molecules in cancer therapeutics.The complexes: [CoL2](ClO4)2 (1), [FeL2](ClO4)2 (2), [NiL2](ClO4)2 (3) and [MnLCl2] (4), with L = diethyl-1,1′-(pyridine-2,6-diyl)bis(5-methyl-1H-pyrazole-3-carboxylate), were synthesized and fully characterized. 相似文献
995.
Karine Evangelista Ana Beatriz Teodoro Jonas Bianchi Lucia Helena Soares Cevidanes Antnio Carlos de Oliveira Ruellas Maria Alves Garcia Silva Jos Valladares-Neto 《The Angle orthodontist》2022,92(1):118
ObjectivesTo analyze the prevalence of mandibular asymmetry in skeletal sagittal malocclusions.Materials and MethodsPubMed/MEDLINE, EMBASE, LILACS, Web of Science, Scopus, LIVIVO and gray literature (OpenGrey, ProQuest, and Google Scholar) were electronically searched. Two independent investigators selected the eligible studies, and assessed risk of bias and certainty of evidence (GRADE). One reviewer independently extracted the data and the second reviewer checked this information. Any disagreement between the reviewers in each phase was resolved by discussion between them and/or involved a third reviewer for final decision.ResultsElectronic search identified 5,132 studies, and 5 observational studies were included. Risk of bias was low in two studies, moderate in one, and high in two. The studies showed high heterogeneity. Mandibular asymmetry ranged from 17.43% to 72.95% in overall samples. Horizontal chin deviation showed a prevalence of 17.66% to 55.6% asymmetry in Class I malocclusions, and 68.98% in vertical asymmetry index. In Class II patients, prevalence of mandibular asymmetry varied from 10% to 25.5% in horizontal chin deviation, and 71.7% in vertical asymmetry index. The Class III sample showed a prevalence of mandibular asymmetry ranging from 22.93% to 78% in horizontal chin deviation and 80.4% in vertical asymmetry index. Patients seeking orthodontic or orthognathic surgery treatment showed greater prevalence of mandibular asymmetry.ConclusionsSkeletal Class III malocclusion showed the greatest prevalence of mandibular asymmetry. Mandibular vertical asymmetry showed a marked prevalence in all malocclusions. However, conclusions should be interpreted with caution due to use of convenience samples and low-quality study outcomes. 相似文献
996.
Samantha A. Chalmers Rajalakshmy Ayilam Ramachandran Sayra J. Garcia Evan Der Leal Herlitz Jeanette Ampudia Dalena Chu Nicole Jordan Ting Zhang Ioannis Parodis Iva Gunnarsson Huihua Ding Nan Shen Michelle Petri Chi Chiu Mok Ramesh Saxena Krishna R. Polu Stephen Connelly Cherie T. Ng Chandra Mohan Chaim Putterman 《The Journal of clinical investigation》2022,132(1)
T cells are central to the pathogenesis of lupus nephritis (LN), a common complication of systemic lupus erythematosus (SLE). CD6 and its ligand, activated leukocyte cell adhesion molecule (ALCAM), are involved in T cell activation and trafficking. Previously, we showed that soluble ALCAM is increased in urine (uALCAM) of patients with LN, suggesting that this pathway contributes to disease. To investigate, uALCAM was examined in 1038 patients with SLE and LN from 5 ethnically diverse cohorts; CD6 and ALCAM expression was assessed in LN kidney cells; and disease contribution was tested via antibody blockade of CD6 in murine models of SLE and acute glomerulonephritis. Extended cohort analysis offered resounding validation of uALCAM as a biomarker that distinguishes active renal involvement in SLE, irrespective of ethnicity. ALCAM was expressed by renal structural cells whereas CD6 expression was exclusive to T cells, with elevated numbers of CD6+ and ALCAM+ cells in patients with LN. CD6 blockade in models of spontaneous lupus and immune-complex glomerulonephritis revealed significant decreases in immune cells, inflammatory markers, and disease measures. Our data demonstrate the contribution of the CD6/ALCAM pathway to LN and SLE, supporting its use as a disease biomarker and therapeutic target. 相似文献
997.
Martina Moras Claude Hattab Pedro Gonzalez-Menendez Claudio M. Fader Michael Dussiot Jerome Larghero Caroline Le Van Kim Sandrina Kinet Naomi Taylor Sophie D. Lefevre Mariano A. Ostuni 《Haematologica》2022,107(1):167
Erythroblast maturation in mammals is dependent on organelle clearance throughout terminal erythropoiesis. We studied the role of the outer mitochondrial membrane protein voltage-dependent anion channel-1 (VDAC1) in human terminal erythropoiesis. We show that short hairpin (shRNA)-mediated downregulation of VDAC1 accelerates erythroblast maturation. Thereafter, erythroblasts are blocked at the orthochromatic stage, exhibiting a significant decreased level of enucleation, concomitant with an increased cell death. We demonstrate that mitochondria clearance starts at the transition from basophilic to polychromatic erythroblast, and that VDAC1 downregulation induces the mitochondrial retention. In damaged mitochondria from non-erythroid cells, VDAC1 was identified as a target for Parkin-mediated ubiquitination to recruit the phagophore. Here, we showed that VDAC1 is involved in phagophore’s membrane recruitment regulating selective mitophagy of still functional mitochondria from human erythroblasts. These findings demonstrate for the first time a crucial role for VDAC1 in human erythroblast terminal differentiation, regulating mitochondria clearance. 相似文献
998.
999.
Elisabet Llaurad Magaly AcevesMartins Jordi PradesTena Maria BesoraMoreno Ignasi PapellGarcia Montse Giralt Amy Davies Lucia Tarro Rosa Sol 《Health expectations》2022,25(1):455
BackgroundAdolescents who participate as peer leaders can benefit and acquire competencies from their peer leadership experience.ObjectivesTo identify the competencies gained by adolescents who participated as peer leaders in a healthy lifestyle study and to determine whether the training characteristics were related to improvement in competencies.DesignThe present study was part of the European Youth Tackling Obesity (EYTO) project, a multicentre social marketing intervention involving four European countries.Setting and ParticipantsEighteen peer leaders (aged 13–15 years, three or five leaders per country) from disadvantaged neighbourhoods received training in designing and implementing activities for their peers.MeasuresThe peer leaders'' confidence, experience and interest in 11 tasks related to lifelong learning competencies were assessed with questions rated on a colour scale at baseline and at the end of the study.ResultsThe peer leaders demonstrated improvements in experience, confidence and interest in different tasks, such as research, website or logo design, oral presentations, social media use and collaboration with people from other countries. They increased their confidence in management tasks (p = 0.03) and their confidence and experience in communication tasks (p = 0.01). The peer leaders from Spain and Portugal had greater improvements than those from the other countries.ConclusionThe peer leaders improved their confidence in management tasks and their confidence and experience in communication tasks. Slight differences were detected in improvement in competencies by country, likely due to the differences in the peer training applied. Recommendations for peer leader training are proposed, although these results should be verified with larger sample size.Patient or Public ContributionThe peer leaders contributed to the design and implementation of the training and intervention. 相似文献