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1.
Osteoarthritis Cartilage ; 28(5): 685-697, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31981738

RESUMO

OBJECTIVE: Innate immune response and particularly terminal complement complex (TCC) deposition are thought to be involved in the pathogenesis of posttraumatic osteoarthritis. However, the possible role of TCC in regulated cell death as well as chondrocyte hypertrophy and senescence has not been unraveled so far and was first addressed using an ex vivo human cartilage trauma-model. DESIGN: Cartilage explants were subjected to blunt impact (0.59 J) and exposed to human serum (HS) and cartilage homogenate (HG) with or without different potential therapeutics: RIPK1-inhibitor Necrostatin-1 (Nec), caspase-inhibitor zVAD, antioxidant N-acetyl cysteine (NAC) and TCC-inhibitors aurintricarboxylic acid (ATA) and clusterin (CLU). Cell death and hypertrophy/senescence-associated markers were evaluated on mRNA and protein level. RESULTS: Addition of HS resulted in significantly enhanced TCC deposition on chondrocytes and decrease of cell viability after trauma. This effect was potentiated by HG and was associated with expression of RIPK3, MLKL and CASP8. Cytotoxicity of HS could be prevented by heat-inactivation or specific inhibitors, whereby combination of Nec and zVAD as well as ATA exhibited highest cell protection. Moreover, HS+HG exposition enhanced the gene expression of CXCL1, IL-8, RUNX2 and VEGFA as well as secretion of IL-6 after cartilage trauma. CONCLUSIONS: Our findings imply crucial involvement of the complement system and primarily TCC in regulated cell death and phenotypic changes of chondrocytes after cartilage trauma. Inhibition of TCC formation or downstream signaling largely modified serum-induced pathophysiologic effects and might therefore represent a therapeutic target to maintain the survival and chondrogenic character of cartilage cells.


Assuntos
Morte Celular/genética , Condrócitos/metabolismo , Complexo de Ataque à Membrana do Sistema Complemento/genética , Hipertrofia/genética , Osteoartrite/genética , Ferimentos não Penetrantes/genética , Acetilcisteína/farmacologia , Idoso , Idoso de 80 Anos ou mais , Ácido Aurintricarboxílico/farmacologia , Cartilagem Articular/citologia , Morte Celular/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Senescência Celular/genética , Condrócitos/efeitos dos fármacos , Condrócitos/patologia , Clusterina/farmacologia , Complexo de Ataque à Membrana do Sistema Complemento/antagonistas & inibidores , Complexo de Ataque à Membrana do Sistema Complemento/efeitos dos fármacos , Complexo de Ataque à Membrana do Sistema Complemento/metabolismo , Inibidores Enzimáticos/farmacologia , Feminino , Sequestradores de Radicais Livres/farmacologia , Humanos , Imidazóis/farmacologia , Imunidade Inata/genética , Indóis/farmacologia , Masculino , Pessoa de Meia-Idade , Oligopeptídeos/farmacologia , Osteoartrite/etiologia , Osteoartrite/metabolismo , Osteoartrite/patologia , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/metabolismo , Ferimentos não Penetrantes/complicações , Ferimentos não Penetrantes/metabolismo
2.
Eur Cell Mater ; 36: 110-127, 2018 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-30215457

RESUMO

Considering the poor intrinsic healing potential of articular cartilage, resident chondrogenic stem/progenitor cells (CSPCs) have gained attention in recent years. Although, CSPCs are attracted by a cartilage injury, knowledge about the post-traumatic behaviour and functional role of this cell population is fairly basic. The present study, not only elaborated on the regenerative capacities of CSPCs, but also illuminated potential immunomodulatory properties after cartilage trauma. Estimation of the CSPC population size within previously impacted cartilage explants by flow-cytometry revealed an increased percentage of CSPC-marker positive cells as compared to unimpacted tissue. In line with this, proliferation, chemotactic migration and in vitro wound healing activity of isolated CSPCs was similarly enhanced after stimulation with trauma-conditioned (TC) medium. Further, a significant increase in pro- and anti-inflammatory gene expression, as well as IL-6 secretion due to TC-medium-stimulation was measured. In this context, antioxidative or chondroanabolic therapeutic intervention alleviated the post-traumatic response of TC-medium-activated CSPCs and substantially influenced CSPC chondrogenic differentiation in different ways. Overall, this study provided novel insights concerning the functional role of CSPCs after cartilage trauma and the effects of a therapeutic intervention in order to improve regenerative processes and prevent cartilage degeneration following trauma.


Assuntos
Cartilagem Articular/lesões , Cartilagem Articular/fisiopatologia , Condrogênese , Fatores Imunológicos/metabolismo , Regeneração , Células-Tronco/citologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/metabolismo , Cartilagem Articular/patologia , Proliferação de Células , Condrócitos/metabolismo , Regulação da Expressão Gênica , Humanos , Interleucina-6/metabolismo , Pessoa de Meia-Idade , Células-Tronco/metabolismo
3.
Mol Psychiatry ; 22(7): 1044-1055, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-27137743

RESUMO

Post-traumatic stress disorder (PTSD) is characterized by exaggerated fear expression and impaired fear extinction. The underlying molecular and cellular mechanisms of PTSD are largely unknown. The current pharmacological and non-pharmacological treatments for PTSD are either ineffective or temporary with high relapse rates. Here we report that adiponectin-deficient mice exhibited normal contextual fear conditioning but displayed slower extinction learning. Infusions of adiponectin into the dentate gyrus (DG) of the hippocampus in fear-conditioned mice facilitated extinction of contextual fear. Whole-cell patch-clamp recordings in brain slices revealed that intrinsic excitability of DG granule neurons was enhanced by adiponectin deficiency and suppressed after treatment with the adiponectin mimetic AdipoRon, which were associated with increased input resistance and hyperpolarized resting membrane potential, respectively. Moreover, deletion of AdipoR2, but not AdipoR1 in the DG, resulted in augmented fear expression and reduced extinction, accompanied by intrinsic hyperexcitability of DG granule neurons. Adiponectin and AdipoRon failed to induce facilitation of fear extinction and elicit inhibition of intrinsic excitability of DG neurons in AdipoR2 knockout mice. These results indicated that adiponectin action via AdipoR2 was both necessary and sufficient for extinction of contextual fear and intrinsic excitability of DG granule neurons, implying that enhancing or dampening DG neuronal excitability may cause resistance to or facilitation of extinction. Therefore, our findings provide a functional link between adiponectin/AdipoR2 activation, DG neuronal excitability and contextual fear extinction, and suggest that targeting adiponectin/AdipoR2 may be used to strengthen extinction-based exposure therapies for PTSD.


Assuntos
Adiponectina/metabolismo , Giro Denteado/metabolismo , Receptores de Adiponectina/metabolismo , Potenciais de Ação/fisiologia , Adiponectina/deficiência , Adiponectina/genética , Animais , Condicionamento Clássico/fisiologia , Modelos Animais de Doenças , Extinção Psicológica/fisiologia , Medo/fisiologia , Feminino , Hipocampo , Aprendizagem/fisiologia , Sistema Límbico , Masculino , Potenciais da Membrana , Erros Inatos do Metabolismo/genética , Erros Inatos do Metabolismo/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/fisiologia , Técnicas de Patch-Clamp , Córtex Pré-Frontal/fisiologia , Transtornos de Estresse Pós-Traumáticos/metabolismo
5.
Tribol Int ; 109: 586-592, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28469288

RESUMO

The menisci protect the articular cartilage by reducing contact pressure in the knee. To restore their function after injury, a new silk fibroin replacement scaffold was developed. To elucidate its tribological properties, friction of the implant was tested against cartilage and glass, where the latter is typically used in tribological cartilage studies. The silk scaffold exhibited a friction coefficient against cartilage of 0.056, which is higher than meniscus against cartilage but in range of the requirements for meniscal replacements. Further, meniscus friction against glass was lower than cartilage against glass, which correlated with the surface lubricin content. Concluding, the tribological properties of the new material suggest a possible long-term chondroprotective function. In contrast, glass always produced high, non-physiological friction coefficients.

6.
Osteoarthritis Cartilage ; 24(12): 2171-2180, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27514995

RESUMO

OBJECTIVE: Mechanical trauma of articular cartilage results in cell loss and cytokine-driven inflammatory response. Subsequent accumulation of reactive oxygen (ROS) and nitrogen (RNS) species enhances the enzymatic degradation of the extracellular matrix (ECM). This study aims on the therapeutic potential of N-acetyl cysteine (NAC) in a human ex vivo cartilage trauma-model, focusing on cell- and chondroprotective features. DESIGN: Human full-thickness cartilage explants were subjected to a defined impact trauma (0.59 J) and treated with NAC. Efficiency of NAC administration was evaluated by following outcome parameters: cell viability, apoptosis rate, anabolic/catabolic gene expression, secretion and activity of matrix metalloproteinases (MMPs) and proteoglycan (PG) release. RESULTS: Continuous NAC administration increased cell viability and reduced the apoptosis rate after trauma. It also suppressed trauma-induced gene expression of ECM-destructive enzymes, such as ADAMTS-4, MMP-1, -2, -3 and -13 in a dosage- and time-depending manner. Subsequent suppression of MMP-2 and MMP-13 secretion reflected these findings on protein level. Moreover, NAC inhibited proteolytic activity of MMPs and reduced PG release. CONCLUSION: In the context of this ex vivo study, we showed not only remarkable cell- and chondroprotective features, but also revealed new encouraging findings concerning the therapeutically effective concentration and treatment-time regimen of NAC. Its defense against chondrocyte apoptosis and catabolic enzyme secretion recommends NAC as a multifunctional add-on reagent for pharmaceutical intervention after cartilage injury. Taken together, our data increase the knowledge on the therapeutic potential of NAC after cartilage trauma and presents a basis for future in vivo studies.


Assuntos
Cartilagem , Acetilcisteína , Condrócitos , Matriz Extracelular , Humanos , Proteoglicanas
7.
AJR Am J Roentgenol ; 207(2): 450-7, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27186635

RESUMO

OBJECTIVE: Molecular breast imaging was implemented in routine clinical practice at a large community-based breast imaging center. The aim of this study was to retrospectively assess the clinical performance of molecular breast imaging as a supplementary screening tool for women with dense breast tissue. MATERIALS AND METHODS: Women with dense breasts and negative mammography results who subsequently underwent screening with 300 MBq (8 mCi) (99m)Tc-sestamibi molecular breast imaging were retrospectively analyzed. Outcome measures included cancer detection rate, recall rate, biopsy rate, and positive predictive values (PPVs). RESULTS: Molecular breast imaging screening of 1696 women in this study resulted in the detection of 13 mammographically occult malignancies, of which 11 were invasive, one was node positive, and one had unknown node positivity. The lesion size ranged from 0.6 to 2.4 cm, with a mean of 1.1 cm. The incremental cancer detection rate was 7.7‰ (95% CI, 4.5-13.1‰), the recall rate was 8.4% (95% CI, 7.2-9.8%), and the biopsy rate was 3.7% (95% CI, 2.9%-4.7%). The PPV for recall (PPV 1) was 9.1% (95% CI, 5.4-15.0%), and the PPV for biopsy (PPV 3) was 19.4% (95% CI, 11.4-30.9%). CONCLUSION: When incorporated into a community-based clinical practice environment, molecular breast imaging yielded a high incremental cancer detection rate of 7.7‰ at an acceptable radiation dose. These results show the utility of molecular breast imaging as a supplementary screening tool to mammography for women with dense breasts.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Imagem Molecular , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Densidade da Mama , Detecção Precoce de Câncer , Feminino , Humanos , Mamografia , Pessoa de Meia-Idade , Doses de Radiação , Compostos Radiofarmacêuticos , Estudos Retrospectivos , Tecnécio Tc 99m Sestamibi
8.
Breast J ; 22(5): 493-500, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27296462

RESUMO

Breast density notification laws, passed in 19 states as of October 2014, mandate that patients be informed of their breast density. The purpose of this study is to assess the impact of this legislation on radiology practices, including performance of breast cancer risk assessment and supplemental screening studies. A 20-question anonymous web-based survey was emailed to radiologists in the Society of Breast Imaging between August 2013 and March 2014. Statistical analysis was performed using Fisher's exact test. Around 121 radiologists from 110 facilities in 34 USA states and 1 Canadian site responded. About 50% (55/110) of facilities had breast density legislation, 36% of facilities (39/109) performed breast cancer risk assessment (one facility did not respond). Risk assessment was performed as a new task in response to density legislation in 40% (6/15) of facilities in states with notification laws. However, there was no significant difference in performing risk assessment between facilities in states with a law and those without (p < 0.831). In anticipation of breast density legislation, 33% (16/48), 6% (3/48), and 6% (3/48) of facilities in states with laws implemented handheld whole breast ultrasound (WBUS), automated WBUS, and tomosynthesis, respectively. The ratio of facilities offering handheld WBUS was significantly higher in states with a law than in states without (p < 0.001). In response to breast density legislation, more than 33% of facilities are offering supplemental screening with WBUS and tomosynthesis, and many are performing formal risk assessment for determining patient management.


Assuntos
Densidade da Mama , Neoplasias da Mama/diagnóstico por imagem , Radiologia/legislação & jurisprudência , Canadá , Feminino , Humanos , Imageamento por Ressonância Magnética/estatística & dados numéricos , Mamografia/estatística & dados numéricos , Radiologia/métodos , Medição de Risco , Inquéritos e Questionários , Ultrassonografia Mamária/estatística & dados numéricos , Estados Unidos
9.
J Fish Dis ; 39(4): 395-410, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25828232

RESUMO

The protistan parasite Ichthyophonus occurred in populations of Pacific herring Clupea pallasii Valenciennes throughout coastal areas of the NE Pacific, ranging from Puget Sound, WA north to the Gulf of Alaska, AK. Infection prevalence in local Pacific herring stocks varied seasonally and annually, and a general pattern of increasing prevalence with host size and/or age persisted throughout the NE Pacific. An exception to this zoographic pattern occurred among a group of juvenile, age 1+ year Pacific herring from Cordova Harbor, AK in June 2010, which demonstrated an unusually high infection prevalence of 35%. Reasons for this anomaly were hypothesized to involve anthropogenic influences that resulted in locally elevated infection pressures. Interannual declines in infection prevalence from some populations (e.g. Lower Cook Inlet, AK; from 20-32% in 2007 to 0-3% during 2009-13) or from the largest size cohorts of other populations (e.g. Sitka Sound, AK; from 62.5% in 2007 to 19.6% in 2013) were likely a reflection of selective mortality among the infected cohorts. All available information for Ichthyophonus in the NE Pacific, including broad geographic range, low host specificity and presence in archived Pacific herring tissue samples dating to the 1980s, indicate a long-standing host-pathogen relationship.


Assuntos
Doenças dos Peixes/epidemiologia , Doenças dos Peixes/parasitologia , Infecções por Mesomycetozoea/epidemiologia , Infecções por Mesomycetozoea/parasitologia , Mesomycetozoea/fisiologia , Alaska , Animais , Doenças dos Peixes/mortalidade , Peixes , Interações Hospedeiro-Parasita , Infecções por Mesomycetozoea/mortalidade , Infecções por Mesomycetozoea/patologia , Oceano Pacífico/epidemiologia , Prevalência , Estações do Ano
10.
Eur Cell Mater ; 29: 22-34, 2015 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-25552426

RESUMO

Mesenchymal stem cells (MSC) were shown to support bone regeneration, when they were locally transplanted into poorly healing fractures. The benefit of systemic MSC transplantation is currently less evident. There is consensus that systemically applied MSC are recruited to the site of injury, but it is debated whether they actually support bone formation. Furthermore, the question arises as to whether circulating MSC are recruited only in case of injury or whether they also participate in mechanically induced bone formation. To answer these questions we injected green fluorescent protein (GFP)-labelled MSC into C57BL/6J mice, which were subjected either to a femur osteotomy or to non-invasive mechanical ulna loading to induce bone formation. We detected GFP-labelled MSC in the early (day 10) and late fracture callus (day 21) by immunohistochemistry. Stromal cell-derived factor 1 (SDF-1 or CXCL-12), a key chemokine for stem cell attraction, was strongly expressed by virtually all cells near the osteotomy--indicating that SDF-1 may mediate cell migration to the site of injury. We found no differences in SDF-1 expression between the groups. Micro-computed tomography (µCT) revealed significantly more bone in the callus of the MSC treated mice compared to untreated controls. The bending stiffness of callus was not significantly altered after MSC-application. In contrast, we failed to detect GFP-labelled MSC in the ulna after non-invasive mechanical loading. Histomorphometry and µCT revealed a significant load-induced increase in bone formation; however, no further increase was found after MSC administration. Concluding, our results suggest that systemically administered MSC are recruited and support bone formation only in case of injury but not in mechanically induced bone formation.


Assuntos
Consolidação da Fratura , Fraturas Ósseas/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/citologia , Osteogênese , Animais , Regeneração Óssea , Calo Ósseo/metabolismo , Calo Ósseo/fisiopatologia , Células Cultivadas , Quimiocina CXCL12/metabolismo , Fraturas Ósseas/metabolismo , Fraturas Ósseas/fisiopatologia , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Imuno-Histoquímica , Masculino , Células-Tronco Mesenquimais/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fatores de Tempo , Microtomografia por Raio-X
11.
Radiology ; 269(3): 887-92, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24023072

RESUMO

In anticipation of breast density notification legislation in the state of California, which would require notification of women with heterogeneously and extremely dense breast tissue, a working group of breast imagers and breast cancer risk specialists was formed to provide a common response framework. The California Breast Density Information Group identified key elements and implications of the law, researching scientific evidence needed to develop a robust response. In particular, issues of risk associated with dense breast tissue, masking of cancers by dense tissue on mammograms, and the efficacy, benefits, and harms of supplementary screening tests were studied and consensus reached. National guidelines and peer-reviewed published literature were used to recommend that women with dense breast tissue at screening mammography follow supplemental screening guidelines based on breast cancer risk assessment. The goal of developing educational materials for referring clinicians and patients was reached with the construction of an easily accessible Web site that contains information about breast density, breast cancer risk assessment, and supplementary imaging. This multi-institutional, multidisciplinary approach may be useful for organizations to frame responses as similar legislation is passed across the United States. Online supplemental material is available for this article.


Assuntos
Neoplasias da Mama/patologia , Mama/patologia , Notificação de Doenças/legislação & jurisprudência , Neoplasias da Mama/diagnóstico por imagem , California , Feminino , Humanos , Mamografia , Programas de Rastreamento , Gravidez , Risco
12.
Zentralbl Chir ; 138(5): 521-9, 2013 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-23460105

RESUMO

The spinal cord is particularly susceptible to ischaemic injury following repair of extensive descending thoracic and thoracoabdominal aortic aneurysms (TAAA). For the past decade, the Mount Sinai group in New York has intensively studied the anatomy of the extensive vascular network surrounding the spinal cord, as well as its dynamic morphology in response to decreased blood pressure and flow. Along with clinical data, experimental findings gave rise to the Collateral Network Concept, by which spinal cord injury in open TAAA repair can be significantly reduced. With the more recent widespread use of endovascular repair, strategies to prevent ischaemic spinal cord damage after extensive segmental artery sacrifice/occlusion are still evolving. The hypothesis that dividing extensive aneurysm repair into two steps may mitigate the impact of diminished blood flow to the collateral network has led to a recently conducted series of staged repair experiments. By exploiting the resources of the collateral network, spinal cord injury could be minimised in staged open, as well as in staged hybrid repair and seems equally adoptable for endovascular procedures. The contribution presented herein provides an overview of clinical and experimental studies on the staged approach. Furthermore, it briefly assesses the anatomic rationale for the collateral network concept.


Assuntos
Aneurisma da Aorta Torácica/cirurgia , Complicações Intraoperatórias/prevenção & controle , Isquemia do Cordão Espinal/prevenção & controle , Circulação Colateral/fisiologia , Procedimentos Endovasculares/métodos , Alemanha , Humanos , Complicações Intraoperatórias/etiologia , Reoperação , Medula Espinal/irrigação sanguínea , Isquemia do Cordão Espinal/etiologia , Pesquisa Translacional Biomédica
13.
Radiology ; 264(2): 371-7, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22692036

RESUMO

PURPOSE: To compare cancer recurrence outcomes on the basis of compliant semiannual versus noncompliant annual ipsilateral mammographic surveillance following breast conservation therapy (BCT). MATERIALS AND METHODS: A HIPAA-compliant retrospective review was performed of post-BCT examinations from 1997 through 2008 by using a deidentified database. The Committee on Human Research did not require institutional review board approval for this study, which was considered quality assurance. Groups were classified according to compliance with institutional post-BCT protocol, which recommends semiannual mammographic examinations of the ipsilateral breast for 5 years. A compliant semiannual examination was defined as an examination with an interval of 0-9 months, although no examination had intervals less than 3 months. A noncompliant annual examination was defined as an examination with an interval of 9-18 months. Cancer recurrence outcomes were compared on the basis of the last examination interval leading to diagnosis. RESULTS: Initially, a total of 10 750 post-BCT examinations among 2329 asymptomatic patients were identified. Excluding initial mammographic follow-up, there were 8234 examinations. Of these, 7169 examinations were semiannual with 94 recurrences detected and 1065 examinations were annual with 15 recurrences detected. There were no differences in demographic risk factors or biopsy rates. Recurrences identified at semiannual intervals were significantly less advanced than those identified at annual intervals (stage I vs stage II, P = .04; stage 0 + stage I vs stage II, P = .03). Nonsignificant findings associated with semiannual versus annual intervals included smaller tumor size (mean, 11.7 vs 15.3 mm; P = .15) and node negativity (98% vs 91%, P = .28). CONCLUSION: Results suggest that a semiannual interval is preferable for ipsilateral mammographic surveillance, allowing detection of a significantly higher proportion of cancer recurrences at an earlier stage than noncompliant annual surveillance.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Mamografia/estatística & dados numéricos , Mastectomia Segmentar , Recidiva Local de Neoplasia/diagnóstico por imagem , Biópsia , Neoplasias da Mama/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Vigilância da População , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo
14.
Radiology ; 261(2): 404-13, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21900620

RESUMO

PURPOSE: To describe the timeliness of follow-up care in community-based settings among women who receive a recommendation for immediate follow-up during the screening mammography process and how follow-up timeliness varies according to facility and facility-level characteristics. MATERIALS AND METHODS: This was an institutional review board-approved and HIPAA-compliant study. Screening mammograms obtained from 1996 to 2007 in women 40-80 years old in the Breast Cancer Surveillance Consortium were examined. Inclusion criteria were a recommendation for immediate follow-up at screening, or subsequent imaging, and observed follow-up within 180 days of the recommendation. Recommendations for additional imaging (AI) and biopsy or surgical consultation (BSC) were analyzed separately. The distribution of time to follow-up care was estimated by using the Kaplan-Meier estimator. RESULTS: Data were available on 214,897 AI recommendations from 118 facilities and 35,622 BSC recommendations from 101 facilities. The median time to subsequent follow-up care after recommendation was 14 days for AI and 16 days for BSC. Approximately 90% of AI follow-up and 81% of BSC follow-up occurred within 30 days. Facilities with higher recall rates tended to have longer AI follow-up times (P < .001). Over the study period, BSC follow-up rates at 15 and 30 days improved (P < .001). Follow-up times varied substantially across facilities. Timely follow-up was associated with larger volumes of the recommended procedures but not notably associated with facility type nor observed facility-level characteristics. CONCLUSION: Most patients with follow-up returned within 3 weeks of the recommendation.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Mamografia , Cooperação do Paciente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/epidemiologia , Feminino , Seguimentos , Humanos , Programas de Rastreamento , Pessoa de Meia-Idade , Sistema de Registros , Fatores de Tempo , Estados Unidos/epidemiologia
15.
Ann Rheum Dis ; 70(8): 1458-60, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20378913

RESUMO

BACKGROUND: Functional polymorphisms in genes of proinflammatory signalling cascades may contribute to the genetic risk of osteoarthritis (OA). OBJECTIVE: To examine a possible association between end-stage OA of the hip and knee joint and a known single nucleotide polymorphism (SNP) of the COX-2 gene promoter. METHODS: The SNP -765 G→C (rs20417) of the COX-2 gene promoter was genotyped by pyrosequencing in 531 (320 women/211 men) patients with OA from the Ulm Osteoarthritis Study and 400 (200 women/200 men) regional controls from the south-west of Germany. RESULTS: In the whole study population the C allele was associated with a lower risk (per allele OR 0.57; 95% CI 0.43 to 0.75, p<0.0001) and the G allele with a higher risk for end-stage OA. Analysis of subgroups confirmed this result for primary, bilateral, hip and knee OA. CONCLUSION: The promoter polymorphism rs20417 of the COX-2 gene contributes to the genetic risk for end-stage hip and knee OA.


Assuntos
Ciclo-Oxigenase 2/genética , Osteoartrite do Quadril/genética , Osteoartrite do Joelho/genética , Polimorfismo de Nucleotídeo Único , Idoso , Condrócitos/enzimologia , Ciclo-Oxigenase 2/metabolismo , Feminino , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite do Quadril/enzimologia , Osteoartrite do Joelho/enzimologia , Regiões Promotoras Genéticas/genética
16.
Breast J ; 17(6): 651-6, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21906209

RESUMO

The aim of this study was to demonstrate convincing evidence that percutaneous breast biopsy may result in displacement of malignant cells that can initiate tumor growth at a separate anatomic site, other than the index lesion. Two patients with malignancy diagnosed by percutaneous breast biopsy were followed up with subsequent imaging. The observation of displaced cells initiating subsequent malignant growth was compared retrospectively with the previous year's outcomes following percutaneous breast biopsy. Two cases of displaced malignant cells resulting in malignant growth at a separate site along the biopsy needle track were demonstrated by imaging. During the preceding year, 1644 biopsies with 298 malignant results were compared with the outcomes of these two patients, resulting in a 0.7% incidence of malignant seeding. No identifiable factors could be identified to predict under what conditions this iatrogenic complication occurs. Although uncommon, percutaneous breast biopsy can result in malignant seeding, and raises issues regarding informed consent and proper subsequent treatment.


Assuntos
Biópsia/efeitos adversos , Neoplasias da Mama/patologia , Mama/patologia , Inoculação de Neoplasia , Feminino , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade
17.
J Cell Biochem ; 109(2): 347-55, 2010 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-19950208

RESUMO

Osteoclast activity has traditionally been regarded as restricted to bone resorption but there is some evidence that also non-resorbing osteoclasts might influence osteoblast activity. The aim of the present study was to further investigate the hypothesis of an anabolic function of non-resorbing osteoclasts by investigating their capability to recruit mesenchymal stem cells (MSC) and to provoke their differentiation toward the osteogenic lineage. Bone-marrow-derived human MSC were exposed to conditioned media (CM) derived from non-resorbing osteoclast cultures, which were generated from human peripheral blood monocytes. Osteogenic marker genes (transcription factor Runx2, bone sialoprotein, alkaline phosphatase (AP), and osteopontin) were significantly increased. Osteogenic differentiation (OD) was also proved by von Kossa and AP staining occurred in the same range as in MSC cultures stimulated with osteogenic supplements. Chemotactic responses of MSC were measured with a modified Boyden chamber assay. CM from osteoclast cultures induced a strong migratory response in MSC, which was greatly reduced in the presence of an anti-human platelet-derived growth factor (PDGF) receptor beta antibody. Correspondingly, significantly increased PDGF-BB concentrations were measured in the CM using a PDGF-BB immunoassay. CM derived from mononuclear cell cultures did not provoke MSC differentiation and had a significantly lower migratory effect on MSC suggesting that the effects were specifically mediated by osteoclasts. In conclusion, it can be suggested that human non-resorbing osteoclasts induce migration and OD of MSC. While effects on MSC migration might be mainly due to PDGF-BB, the factors inducing OD remain to be elucidated.


Assuntos
Comunicação Celular , Diferenciação Celular , Movimento Celular , Células-Tronco Mesenquimais/fisiologia , Osteoclastos/fisiologia , Osteogênese , Fosfatase Alcalina/genética , Becaplermina , Células da Medula Óssea/citologia , Células da Medula Óssea/fisiologia , Reabsorção Óssea , Quimiotaxia , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Meios de Cultivo Condicionados , Humanos , Sialoproteína de Ligação à Integrina , Células-Tronco Mesenquimais/citologia , Monócitos/metabolismo , Osteoclastos/citologia , Osteopontina/genética , Fator de Crescimento Derivado de Plaquetas/metabolismo , Proteínas Proto-Oncogênicas c-sis , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Sialoglicoproteínas/genética
18.
Radiology ; 256(1): 74-82, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20505059

RESUMO

PURPOSE: To examine time trends in radiologists' interpretive performance at screening mammography between 1996 and 2004. MATERIALS AND METHODS: All study procedures were institutional review board approved and HIPAA compliant. Data were collected on subsequent screening mammograms obtained from 1996 to 2004 in women aged 40-79 years who were followed up for 1 year for breast cancer. Recall rate, sensitivity, and specificity were examined annually. Generalized estimating equation (GEE) and random-effects models were used to test for linear trend. The area under the receiver operating characteristic curve (AUC), tumor histologic findings, and size of the largest dimension or diameter of the tumor were also examined. RESULTS: Data on 2,542,049 subsequent screening mammograms and 12,498 cancers diagnosed in the follow-up period were included in this study. Recall rate increased from 6.7% to 8.6%, sensitivity increased from 71.4% to 83.8%, and specificity decreased from 93.6% to 91.7%. In GEE models, adjusted odds ratios per calendar year were 1.04 (95% confidence interval [CI]: 1.02, 1.05) for recall rate, 1.09 (95% CI: 1.07. 1.12) for sensitivity, and 0.96 (95% CI: 0.95, 0.98) for specificity (P < .001 for all). Random-effects model results were similar. The AUC increased over time: 0.869 (95% CI: 0.861, 0.877) for 1996-1998, 0.884 (95% CI: 0.879, 0.890) for 1999-2001, and 0.891 (95% CI: 0.885, 0.896) for 2002-2004 (P < .001). Tumor histologic findings and size remained constant. CONCLUSION: Recall rate and sensitivity for screening mammograms increased, whereas specificity decreased from 1996 to 2004 among women with a prior mammogram. This trend remained after accounting for risk factors. The net effect was an improvement in overall discrimination, a measure of the probability that a mammogram with cancer in the follow-up period has a higher Breast Imaging Reporting and Data System assessment category than does a mammogram without cancer in the follow-up period.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Competência Clínica , Mamografia , Padrões de Prática Médica/estatística & dados numéricos , Adulto , Idoso , Área Sob a Curva , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Curva ROC , Interpretação de Imagem Radiográfica Assistida por Computador , Sensibilidade e Especificidade , Fatores de Tempo , Estados Unidos/epidemiologia
19.
Radiology ; 255(2): 354-61, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20413750

RESUMO

PURPOSE: To develop criteria to identify thresholds for minimally acceptable physician performance in interpreting screening mammography studies and to profile the impact that implementing these criteria may have on the practice of radiology in the United States. MATERIALS AND METHODS: In an institutional review board-approved, HIPAA-compliant study, an Angoff approach was used in two phases to set criteria for identifying minimally acceptable interpretive performance at screening mammography as measured by sensitivity, specificity, recall rate, positive predictive value (PPV) of recall (PPV(1)) and of biopsy recommendation (PPV(2)), and cancer detection rate. Performance measures were considered separately. In phase I, a group of 10 expert radiologists considered a hypothetical pool of 100 interpreting physicians and conveyed their cut points of minimally acceptable performance. The experts were informed that a physician's performance falling outside the cut points would result in a recommendation to consider additional training. During each round of scoring, all expert radiologists' cut points were summarized into a mean, median, mode, and range; these were presented back to the group. In phase II, normative data on performance were shown to illustrate the potential impact cut points would have on radiology practice. Rescoring was done until consensus among experts was achieved. Simulation methods were used to estimate the potential impact of performance that improved to acceptable levels if effective additional training was provided. RESULTS: Final cut points to identify low performance were as follows: sensitivity less than 75%, specificity less than 88% or greater than 95%, recall rate less than 5% or greater than 12%, PPV(1) less than 3% or greater than 8%, PPV(2) less than 20% or greater than 40%, and cancer detection rate less than 2.5 per 1000 interpretations. The selected cut points for performance measures would likely result in 18%-28% of interpreting physicians being considered for additional training on the basis of sensitivity and cancer detection rate, while the cut points for specificity, recall, and PPV(1) and PPV(2) would likely affect 34%-49% of practicing interpreters. If underperforming physicians moved into the acceptable range, detection of an additional 14 cancers per 100000 women screened and a reduction in the number of false-positive examinations by 880 per 100000 women screened would be expected. CONCLUSION: This study identified minimally acceptable performance levels for interpreters of screening mammography studies. Interpreting physicians whose performance falls outside the identified cut points should be reviewed in the context of their specific practice settings and be considered for additional training.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Competência Clínica/normas , Mamografia/normas , Programas de Rastreamento/normas , Radiologia/normas , Biópsia , Feminino , Humanos , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Estados Unidos
20.
Hum Reprod ; 25(2): 345-53, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19897857

RESUMO

BACKGROUND: The levonorgestrel-releasing intrauterine system (LNG-IUS) is a highly effective contraceptive. However, during early months of use unscheduled vaginal bleeding is common, sometimes leading to discontinuation. This study aimed to determine whether intermittent administration of progesterone receptor modulator CDB-2914 would suppress unscheduled bleeding during the first 4 months after insertion of the LNG-IUS. METHODS: CDB-2914 150 mg, in divided doses, or placebo tablets, were administered over three consecutive days starting on Days 21, 49 and 77 after LNG-IUS insertion, in a double-blind randomized controlled trial of women aged 19-49 years, newly starting use of LNG-IUS. Daily bleeding diaries were completed for 6 months, and summarized across blocks as percentage days bleeding/spotting (BS%). RESULTS: Of 69 women randomized to receive CDB-2914, and 67 placebo, 61 and 55, respectively, completed the trial. BS% decreased with time in both arms, but showed a much steeper treatment-phase gradient in the placebo arm (P < 0.0001), so that a benefit of CDB-2914 in the 28 days after first treatment (-11% points, 95% CI -19 to -2), converted to a disadvantage by 64 days after the third treatment (+10% points, 95% CI 1-18). CONCLUSIONS: The effect of CDB-2914 on BS% was initially beneficial but then by third treatment was disadvantageous. Nevertheless, only 3% (4/136) of all women discontinued LNG-IUS. These findings give insight into possible mechanisms and suggest future research directions. ISRCTN Trial no. ISRCTN58283041; EudraCT no. 2006-006511-72.


Assuntos
Dispositivos Intrauterinos Medicados , Levanogestrel/administração & dosagem , Metrorragia/prevenção & controle , Norpregnadienos/uso terapêutico , Adulto , Anticoncepcionais Femininos/administração & dosagem , Feminino , Humanos , Pessoa de Meia-Idade , Receptores de Progesterona/efeitos dos fármacos
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