Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 22
Filtrar
Más filtros

Bases de datos
País/Región como asunto
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
Int J Mol Sci ; 25(13)2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-39000064

RESUMEN

Chondrosarcoma (CS) is a rare malignant bone sarcoma that primarily affects cartilage cells in the femur and pelvis. While most subtypes exhibit slow growth with a very good prognosis, some aggressive subtypes have a poorer overall survival. CS is known for its resistance to chemotherapy and radiotherapy, leaving surgery as the sole effective therapeutic option. Cold physical plasma (CPP) has been explored in vitro as a potential therapy, demonstrating positive anti-tumor effects on CS cells. This study investigated the synergistic effects of combining CPP with cytostatics on CS cells. The chemotherapeutic agents cisplatin, doxorubicin, and vincristine were applied to two CS cell lines (CAL-78 and SW1353). After determining their IC20 and IC50, they were combined with CPP in both cell lines to assess their impact on the cell proliferation, viability, metabolism, and apoptosis. This combined approach significantly reduced the cell proliferation and viability while increasing the apoptosis signals compared to cytostatic therapy alone. The combination of CPP and chemotherapeutic drugs shows promise in targeting chemoresistant CS cells, potentially improving the prognosis for patients in clinical settings.


Asunto(s)
Apoptosis , Neoplasias Óseas , Proliferación Celular , Supervivencia Celular , Condrosarcoma , Doxorrubicina , Gases em Plasma , Condrosarcoma/tratamiento farmacológico , Condrosarcoma/patología , Humanos , Gases em Plasma/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Doxorrubicina/farmacología , Apoptosis/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/patología , Neoplasias Óseas/terapia , Antineoplásicos/farmacología , Cisplatino/farmacología , Vincristina/farmacología , Terapia Combinada
2.
Nanomedicine ; 13(8): 2415-2423, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28821464

RESUMEN

Porous tantalum components are widely used for complex acetabular reconstructions in revision hip arthroplasty. Multiple other metal alloys such as titanium-aluminum-vanadium or cobalt-chromium-molybdenum are principally used in artificial joint setups. We report a case of tantalum component failure being both cause and effect of a multiple metal exposure. Our aims were to assess and to characterize associated particle exposure and biological consequences. Metal level quantification revealed substantial in vivo exposure to particulate and dissociated tantalum, zirconium, chromium, cobalt, molybdenum, titanium, aluminum and vanadium in periprosthetic compartments. Aside from micron-sized particles, nanoparticles of a broad size range and elemental composition were obtained. Histological exams verified a spectrum of necrotic changes in the periprosthetic tissues. In the presented case tantalum release was accompanied by concomitance of particles originating from other utilized metals. We conclude that an overall in vivo exposure assessment is mandatory for realistic appraisal of metal toxicity and associated risks.


Asunto(s)
Artroplastia de Reemplazo de Cadera/efectos adversos , Prótesis de Cadera/efectos adversos , Falla de Prótesis/efectos adversos , Tantalio/efectos adversos , Femenino , Humanos , Persona de Mediana Edad , Necrosis/etiología , Necrosis/patología , Tamaño de la Partícula
3.
Small ; 10(21): 4340-51, 2014 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-24990430

RESUMEN

Mesenchymal stromal cells (MSCs) are promising candidates in regenerative cell-therapies. However, optimizing their number and route of delivery remains a critical issue, which can be addressed by monitoring the MSCs' bio-distribution in vivo using super-paramagnetic iron-oxide nanoparticles (SPIONs). In this study, amino-polyvinyl alcohol coated (A-PVA) SPIONs are introduced for cell-labeling and visualization by magnetic resonance imaging (MRI) of human MSCs. Size and surface charge of A-PVA-SPIONs differ depending on their solvent. Under MSC-labeling conditions, A-PVA-SPIONs have a hydrodynamic diameter of 42 ± 2 nm and a negative Zeta potential of 25 ± 5 mV, which enable efficient internalization by MSCs without the need to use transfection agents. Transmission X-ray microscopy localizes A-PVA-SPIONs in intracellular vesicles and as cytosolic single particles. After identifying non-interfering cell-assays and determining the delivered and cellular dose, in addition to the administered dose, A-PVA-SPIONs are found to be non-toxic to MSCs and non-destructive towards their multi-lineage differentiation potential. Surprisingly, MSC migration is increased. In MRI, A-PVA-SPION-labeled MSCs are successfully visualized in vitro and in vivo. In conclusion, A-PVA-SPIONs have no unfavorable influences on MSCs, although it becomes evident how sensitive their functional behavior is towards SPION-labeling. And A-PVA-SPIONs allow MSC-monitoring in vivo.


Asunto(s)
Rastreo Celular/métodos , Dextranos/química , Imagen por Resonancia Magnética/métodos , Nanopartículas de Magnetita/química , Células Madre Mesenquimatosas/citología , Alcohol Polivinílico/química , Anciano , Animales , Diferenciación Celular , Rastreo Celular/instrumentación , Células Cultivadas , Medios de Contraste/química , Dextranos/síntesis química , Femenino , Humanos , Imagen por Resonancia Magnética/instrumentación , Masculino , Trasplante de Células Madre Mesenquimatosas/métodos , Células Madre Mesenquimatosas/fisiología , Persona de Mediana Edad , Ratas , Ratas Endogámicas Lew
4.
Heliyon ; 10(8): e29719, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38681575

RESUMEN

The gadolinium-based contrast agent DOTA-Gd is clinically used in combination with local anesthetics for direct magnetic resonance arthrography. It remains unclear whether gadolinium uptake into cartilage is influenced by co-administration of bupivacaine or ropivacaine and whether DOTA-Gd alters their chondrotoxicity. Gadolinium quantification of chondrogenic spheroids revealed enhanced gadolinium uptake after simultaneous exposure to local anesthetics. Analyses of the spatial gadolinium distribution using synchrotron X-ray-fluorescence scanning indicates gadolinium exposed chondrocytes. In vitro exposure to DOTA-Gd does not alter viability and proliferation of human chondrocytes and the chondrotoxic potential of the anesthetics. Reduced viability induced by ropivacaine was found to be reversible, while exposure to bupivacaine leads to irreversible cell death. Our data suggest that ropivacaine is more tolerable than bupivacaine and that DOTA-Gd exposure does not alter the cytotoxicity of both anesthetics. Enhanced gadolinium uptake into cartilage due to co-administration of anesthetics should find attention.

5.
Appl Opt ; 52(8): 1655-62, 2013 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-23478769

RESUMEN

We present a method for producing monolithically integrated complementary metal-oxide-semiconductor (CMOS) optical filters with different and customer-specific responses. The filters are constituted by a Fabry-Perot resonator formed by two Bragg mirrors separated by a patterned cavity. The filter response can be tuned by changing the geometric parameters of the patterning, and consequently the cavity effective refractive index. In this way, many different filters can be produced at once on a single chip, allowing multichanneling. The filter has been designed, produced, and characterized. The results for a chip with 24 filters are presented.

6.
Biomedicines ; 11(2)2023 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-36830862

RESUMEN

Bone generally displays a high intrinsic capacity to regenerate. Nonetheless, large osseous defects sometimes fail to heal. The treatment of such large segmental defects still represents a considerable clinical challenge. The regeneration of large bone defects often proves difficult, since it relies on the formation of large amounts of bone within an environment impedimental to osteogenesis, characterized by soft tissue damage and hampered vascularization. Consequently, research efforts have concentrated on tissue engineering and regenerative medical strategies to resolve this multifaceted challenge. In this review, we summarize, critically evaluate, and discuss present approaches in light of their clinical relevance; we also present future advanced techniques for bone tissue engineering, outlining the steps to realize for their translation from bench to bedside. The discussion includes the physiology of bone healing, requirements and properties of natural and synthetic biomaterials for bone reconstruction, their use in conjunction with cellular components and suitable growth factors, and strategies to improve vascularization and the translation of these regenerative concepts to in vivo applications. We conclude that the ideal all-purpose material for scaffold-guided bone regeneration is currently not available. It seems that a variety of different solutions will be employed, according to the clinical treatment necessary.

7.
Orthopadie (Heidelb) ; 52(3): 186-195, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36853395

RESUMEN

The success of hip arthroplasty is based on modern materials in addition to the continuous development of surgical techniques and clinical experience gained over six decades. The biocompatible implant materials used in hip arthroplasty can be textured or coated with biomimetic surfaces to ensure durable component ingrowth and moderate host response. Material integrity plays a critical role in the durability of the stable interface between implant components and periprosthetic tissues. Inflammation at the interfaces due to the release of degradation products from the implant materials is one of the causes of hip arthroplasty failure. This review summarizes the implant materials currently used in hip arthroplasty, their preclinical testing and the postoperative neogenesis of periprosthetic tissues, and the interactions of periprosthetic bone and the implant materials at the periprosthetic interfaces.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Artroplastia de Reemplazo de Cadera/efectos adversos , Materiales Biocompatibles , Prótesis e Implantes , Articulaciones
8.
Stem Cell Res Ther ; 14(1): 315, 2023 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-37924114

RESUMEN

BACKGROUND: Bone marrow-derived mesenchymal stromal cells (BM-MSCs) are used in regenerative medicine and related research involving immunomodulatory, anti-inflammatory, anti-fibrotic and regenerative functions. Isolation of BM-MSCs from samples obtained during total hip arthroplasty (THA) is routinely possible. Advanced age and comorbidities of the majority of patients undergoing THA limit their applicability. Our study aimed to evaluate the potential of bone marrow obtained during periacetabular osteotomy (PAO) as a novel source of BM-MSCs from young donors by analyzing cell yield and cell characteristics. METHODS: Bone samples were obtained from the anterior Os ilium or superior Os pubis during PAO and from the femoral cavity during primary THA. Isolation of bone marrow-derived mononuclear cells (BM-MNCs) was performed by density gradient centrifugation. The samples from PAO and THA patients were compared in terms of BM-MSC yield, colony formation and the proportion of BM-MSCs within the BM-MNC population using flow cytometry analysis. The cells were characterized based on the expression of BM-MSC-specific surface markers. The functionality of the cells was compared by quantifying post-thaw viability, metabolic activity, proliferation capacity, senescence-associated beta galactosidase (SA-ß-gal) expression, trilineage differentiation potential and major secretome proteins. RESULTS: Isolation of BM-MNCs was possible in a reliable and reproducible manner when using bone from PAO containing more than 0.24 g bone marrow. PAO patients were younger than patients of the THA group. Bone obtained during PAO contained less bone marrow and led to a lower BM-MSC number after the first cell culture passage compared to BM-MSCs obtained during THA. BM-MSCs from PAO samples are characterized by a higher proliferation capacity. This results in a higher yield in cell culture passage two, when normalized to the sample weight. BM-MSCs from PAO patients showed increased secretion of TGF-ß1, TIMP2, and VEGF upon osteogenic differentiation. BM-MSCs from PAO and THA patients revealed similar results regarding the onset of SA-ß-gal expression and trilineage differentiation capacity. CONCLUSIONS: We suggest that bone obtained during PAO is a promising novel source for BM-MSCs from young donors. Limited absolute cell yield due to low sample weight must be considered in early cell culture passages and might be critical for the range of clinical applications possible for BM-MSCs from this source. The higher proliferation capacity and increased growth factor secretion of BM-MSCs from young donors may be beneficial for future regenerative cell therapies, in vitro models, and tissue engineering.


Asunto(s)
Células Madre Mesenquimatosas , Osteogénesis , Humanos , Células Cultivadas , Médula Ósea , Células Madre Mesenquimatosas/metabolismo , Diferenciación Celular , Osteotomía , Células de la Médula Ósea , Proliferación Celular
9.
EFORT Open Rev ; 8(6): 409-423, 2023 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-37289098

RESUMEN

Cold physical plasma (CPP) technology is of high promise for various medical applications. The interplay of specific components of physical plasma with living cells, tissues and organs on a structural and functional level is of paramount interest with the aim to induce therapeutic effects in a controlled and replicable fashion. In contrast to other medical disciplines such as dermatology and oromaxillofacial surgery, research reports on CPP application in orthopaedics are scarce. The present implementation of CPP in orthopaedics involves surface modifications of orthopaedic materials and biomaterials to optimize osseointegration. In addition, the influence of CPP on musculoskeletal cells and tissues is a focus of research, including possible adverse reactions and side effects. Its bactericidal aspects make CPP an attractive supplement to current treatment regimens in case of microbial inflammations such as periprosthetic joint infections. Attributed anticancerogenic and pro-apoptotic effects underline the clinical relevance of CPP as an additive in treating malignant bone lesions. The present review outlines ongoing research in orthopaedics involving CPP; it distinguishes considerations for safe application and the need for more evidence-based research to facilitate robust clinical implementation.

10.
Front Bioeng Biotechnol ; 11: 1264409, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38026873

RESUMEN

In musculoskeletal surgery, the treatment of large bone defects is challenging and can require the use of bone graft substitutes to restore mechanical stability and promote host-mediated regeneration. The use of bone allografts is well-established in many bone regenerative procedures, but is associated with low rates of ingrowth due to pre-therapeutic graft processing. Cold physical plasma (CPP), a partially ionized gas that simultaneously generates reactive oxygen (O2) and nitrogen (N2) species, is suggested to be advantageous in biomedical implant processing. CPP is a promising tool in allograft processing for improving surface characteristics of bone allografts towards enhanced cellularization and osteoconduction. However, a preclinical assessment regarding the feasibility of pre-therapeutic processing of allogeneic bone grafts with CPP has not yet been performed. Thus, this pilot study aimed to analyze the bone morphology of CPP processed allografts using synchrotron radiation-based microcomputed tomography (SR-µCT) and to analyze the effects of CPP processing on human bone cell viability and function. The analyzes, including co-registration of pre- and post-treatment SR-µCT scans, revealed that the main bone morphological properties (total volume, mineralized volume, surface area, and porosity) remained unaffected by CPP treatment if compared to allografts not treated with CPP. Varying effects on cellular metabolic activity and alkaline phosphatase activity were found in response to different gas mixtures and treatment durations employed for CPP application. It was found that 3 min CPP treatment using a He + 0.1% N2 gas mixture led to the most favourable outcome regarding a significant increase in bone cell viability and alkaline phosphatase activity. This study highlights the promising potential of pre-therapeuthic bone allograft processing by CPP prior to intraoperative application and emphasizes the need for gas source and treatment time optimization for specific applications.

11.
Lab Chip ; 23(15): 3405-3423, 2023 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-37395321

RESUMEN

Throughout life, continuous remodelling is part of human bone biology and depends on the simultaneous action of physicochemical parameters such as oxygen tension and varying mechanical load. Thus, suitable model systems are needed, which allow concomitant modulation of these factors to recapitulate in vivo bone formation. Here, we report on the development of a first microphysiological system (MPS) that enables perfusion, environment-independent regulation of the oxygen tension as well as precise quantification and control of mechanical load. To demonstrate the use of the MPS for future studies on the (patho-)biology of bone, we built a simplified 3D model for early de novo bone formation. Primary human osteoblasts (OBs), which are the key players during this process, were seeded onto type I collagen scaffolds and cultured in the MPS. We could not only monitor cell viability and metabolism of OBs under varied physicochemical conditions, but also visualise the mineralisation of the extracellular matrix. In summary, we present a MPS that uniquely combines the independent control of physicochemical parameters and allows investigation of their influence on bone biology. We consider our MPS highly valuable to gain deeper insights into (patho-)physiological processes of bone formation in the future.


Asunto(s)
Huesos , Sistemas Microfisiológicos , Humanos , Osteoblastos , Oxígeno/metabolismo , Biología , Ingeniería de Tejidos
12.
Reprod Toxicol ; 100: 155-162, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33278556

RESUMEN

25 years after the first Berlin Workshop on Developmental Toxicity this 10th Berlin Workshop aimed to bring together international experts from authorities, academia and industry to consider scientific, methodologic and regulatory aspects in risk assessment of developmental toxicity and to debate alternative strategies in testing developmental effects in the future. Proposals for improvement of the categorization of developmental effects were discussed as well as the update of the DevTox database as valuable tool for harmonization. The development of adverse outcome pathways relevant to developmental neurotoxicity (DNT) was debated as a fundamental improvement to guide the screening and testing for DNT using alternatives to animal methods. A further focus was the implementation of an in vitro mechanism-based battery, which can support various regulatory applications associated with the assessment of chemicals and mixtures. More interdisciplinary and translation research should be initiated to accelerate the development of new technologies to test developmental toxicity. Technologies in the pipeline are (i) high throughput imaging techniques, (ii) models for DNT screening tests, (iii) use of computer tomography for assessment of thoracolumbar supernumerary ribs in animal models, and (iv) 3D biofabrication of bone development and regeneration tissue models. In addition, increased collaboration with the medical community was suggested to improve the relevance of test results to humans and identify more clinically relevant endpoints. Finally, the participants agreed that this conference facilitated better understanding innovative approaches that can be useful for the identification of developmental health risks due to exposure to chemical substances.


Asunto(s)
Desarrollo Óseo/efectos de los fármacos , Educación , Enfermedades del Sistema Nervioso/inducido químicamente , Toxicología/métodos , Aniversarios y Eventos Especiales , Berlin , Uso de Internet , Sistema Nervioso/efectos de los fármacos , Sistema Nervioso/crecimiento & desarrollo , Medición de Riesgo
13.
Reprod Toxicol ; 89: 124-129, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31288076

RESUMEN

Representatives of applied science (e.g. governmental organizations, academia, and industry) met to discuss the progress towards a harmonized human health risk assessment in developmental toxicology of plant protection products, biocidal products, and other environmental chemicals at the 9th Berlin Workshop on Developmental Toxicity held in September 2018. Within the focus of the scientific discussion were the future of in-vitro methods for developmental and reproductive toxicology, the potential relevance of alternative species in testing of developmental effects, and risk and hazard assessment of developmental and endocrine effects. Furthermore, the need for a harmonized terminology for classification of anomalies in laboratory animals in developmental toxicity studies aiming for human health risk assessment was determined. Here, the DevTox database was identified as an extremely valuable tool. Overall, the participants agreed that still one of the biggest challenges for testing developmental toxicity in the 21st century is the development of animal-free test strategies and alternatives to animal testing that could provide human-relevant information in a rapid, efficient, and mechanistically informative manner.


Asunto(s)
Alternativas al Uso de Animales/métodos , Bases de Datos Factuales/tendencias , Reproducción/efectos de los fármacos , Toxicología/métodos , Alternativas al Uso de Animales/tendencias , Animales , Berlin , Medición de Riesgo , Especificidad de la Especie , Terminología como Asunto , Toxicología/tendencias
14.
Genes (Basel) ; 9(5)2018 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-29748516

RESUMEN

Bone is a complex tissue with a variety of functions, such as providing mechanical stability for locomotion, protection of the inner organs, mineral homeostasis and haematopoiesis. To fulfil these diverse roles in the human body, bone consists of a multitude of different cells and an extracellular matrix that is mechanically stable, yet flexible at the same time. Unlike most tissues, bone is under constant renewal facilitated by a coordinated interaction of bone-forming and bone-resorbing cells. It is thus challenging to recreate bone in its complexity in vitro and most current models rather focus on certain aspects of bone biology that are of relevance for the research question addressed. In addition, animal models are still regarded as the gold-standard in the context of bone biology and pathology, especially for the development of novel treatment strategies. However, species-specific differences impede the translation of findings from animal models to humans. The current review summarizes and discusses the latest developments in bone tissue engineering and organoid culture including suitable cell sources, extracellular matrices and microfluidic bioreactor systems. With available technology in mind, a best possible bone model will be hypothesized. Furthermore, the future need and application of such a complex model will be discussed.

15.
Hum Pathol ; 38(4): 668-72, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17367608

RESUMEN

Diagnosis of primary spindle cell tumors of the spleen is challenging because of the limited immunologic and cytogenetic characterization of this rare entity. We report a case of primary follicular dendritic cell (FDC) sarcoma of the spleen in a 44-year-old woman. Indications for FDC included positive staining for CD21, Ki-M4P, CD14, and fascin. Expression of both standard FDC markers CD23 and CD35 was detected immunohistochemically using tyramide signal amplification. Cytogenetic analysis revealed multiple clonal chromosomal aberrations involving unbalanced translocations of chromosomes X, 3, 5, 7, 8, 9, and 10, leading to net gains at 3q, 7p, 8q, and 9q and net losses at Xp, 8p, 9p, and 10p. Loss at Xp has been described previously in another tumor with FDC features, suggesting that this aberration might play a common role in this malignancy.


Asunto(s)
Sarcoma/patología , Neoplasias del Bazo/patología , Adulto , Aberraciones Cromosómicas , Cromosomas Humanos Par 10/genética , Cromosomas Humanos Par 3/genética , Cromosomas Humanos Par 5/genética , Cromosomas Humanos Par 7/genética , Cromosomas Humanos Par 8/genética , Cromosomas Humanos Par 9/genética , Cromosomas Humanos X/genética , Células Dendríticas Foliculares/patología , Resultado Fatal , Femenino , Humanos , Receptores de Complemento 3b/análisis , Receptores de IgE/análisis , Sarcoma/genética , Neoplasias del Bazo/genética , Translocación Genética
16.
Genes (Basel) ; 8(10)2017 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-29019963

RESUMEN

In the early days of pharmacy, the development of new drugs was frequently achieved by restless chemists who worked solitarily, day by day for years [...].

17.
Genes (Basel) ; 8(10)2017 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-28953246

RESUMEN

Air quality depends on the various gases and particles present in it. Both natural phenomena and human activities affect the cleanliness of air. In the last decade, many countries experienced an unprecedented industrial growth, resulting in changing air quality values, and correspondingly, affecting our life quality. Air quality can be accessed by employing microchips that qualitatively and quantitatively determine the present gases and dust particles. The so-called particular matter 2.5 (PM2.5) values are of high importance, as such small particles can penetrate the human lung barrier and enter the blood system. There are cancer cases related to many air pollutants, and especially to PM2.5, contributing to exploding costs within the healthcare system. We focus on various current and potential future air pollutants, and propose solutions on how to protect our health against such dangerous substances. Recent developments in the Organ-on-Chip (OoC) technology can be used to study air pollution as well. OoC allows determination of pollutant toxicity and speeds up the development of novel pharmaceutical drugs.

18.
Biomaterials ; 98: 31-40, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27179133

RESUMEN

In hip arthroplasty the implants' articulating surfaces can be made of a cobalt-chromium-molybdenum (CoCrMo) alloy. The use of these metal-on-metal (MoM) pairings can lead to the release of wear products such as metallic particles and dissociated metal species, raising concerns regarding their safety amongst orthopedic surgeons and the public. MoM-wear particles are reported to be heterogeneous in their physicochemical properties, are capable of inducing adverse effects on a cellular level and are thought to be involved in relevant clinical problems like aseptic osteolysis. Yet, it remains elusive how MoM-wear affects bone forming cells and their progenitors: bone marrow residing mesenchymal stromal cells (MSCs). This study introduces an assessment of the in vivo exposure to particulate and dissociated Co and Cr and evaluates the effects of MoM-wear on MSCs. The exposure to MoM-wear products in vivo and in vitro leads to a decrease in MSCs' osteogenic matrix mineralization and alkaline phosphatase activity on a cellular and systemic level. In conclusion, MoM-wear products are released in the periprosthetic region and elevate bone marrow Co and Cr concentrations towards levels that impair osteogenic differentiation of MSCs. Therefore, the ongoing use of CoCrMo alloys for articulating surfaces in joint replacement implants needs critical reconsideration.


Asunto(s)
Prótesis de Cadera/efectos adversos , Células Madre Mesenquimatosas/metabolismo , Prótesis Articulares de Metal sobre Metal/efectos adversos , Material Particulado/efectos adversos , Anciano , Fosfatasa Alcalina/sangre , Matriz Ósea/metabolismo , Diferenciación Celular , Proliferación Celular , Supervivencia Celular , Femenino , Humanos , Masculino , Células Madre Mesenquimatosas/patología , Persona de Mediana Edad , Minerales/metabolismo , Osteogénesis
19.
Nanomedicine (Lond) ; 10(14): 2139-51, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26214354

RESUMEN

AIMS: First, it will be investigated if amino-polyvinyl alcohol-coated superparamagnetic iron oxide nanoparticles (A-PVA-SPIONs) are suitable for MRI contrast enhancement in bone marrow. Second, the impact of A-PVA-SPION exposure in vivo on the viability and key functions of local bone marrow stromal cells (BMSCs) will be investigated. MATERIAL & METHODS: Animals were systemically injected with A-PVA-SPIONs, followed by a 7-day survival time. Accumulation of A-PVA-SPIONs was confirmed by MRI, histology and inductively coupled plasma optical emission spectrometry. BMSCs were isolated from bone marrow for in vitro assessment of their viability and regenerative key functions. RESULTS: In this study, A-PVA-SPIONs were found to accumulate in bone marrow and increase the BMSCs' metabolic activity and migration rate. CONCLUSION: A-PVA-SPIONs appear suitable for contrast enhancement in bone marrow while our data suggest an influence on the BMSCs biology that necessitates future research.


Asunto(s)
Médula Ósea/metabolismo , Compuestos Férricos/química , Células Madre Mesenquimatosas/metabolismo , Nanopartículas/química , Nanopartículas/metabolismo , Alcohol Polivinílico/química , Animales , Medios de Contraste/química , Medios de Contraste/metabolismo , Ratas
20.
J Clin Microbiol ; 44(6): 2019-24, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16757592

RESUMEN

The species Campylobacter fetus is divided into the subspecies C. fetus subsp. venerealis and C. fetus subsp. fetus, which differ in their epidemiologies and clinical importance. The differences between these subspecies make accurate distinction between the two essential. First, the value of seven key tests for the traditional differentiation of C. fetus was investigated. Afterwards, the results of the phenotypic differentiation and PCR were compared to address the question of the reliability of this PCR assay. Altogether, 103 C. fetus isolates were investigated, including the type strains of C. fetus subsp. fetus and C. fetus subsp. venerealis. Depending on the result of the glycine tolerance test, the isolates could be separated into 81 C. fetus subsp. venerealis isolates (glycine intolerant) and 22 C. fetus subsp. fetus isolates (glycine tolerant). For all C. fetus subsp. venerealis strains tested, the results of the selenite reduction assay and sensitivity to metronidazole and cefoperazone completely agreed with the results of the glycine tolerance test (correspondence, 100%). Seventy-three C. fetus subsp. venerealis isolates did not grow at 42 degrees C (correspondence, 90.1%), but eight isolates showed a faintly discernible, flat, dark gray growth. For 22 C. fetus subsp. fetus isolates, the results of additional phenotypic tests only partly agreed with the results of the glycine tolerance test. For C. fetus subsp. fetus the results of the glycine tolerance test showed a relatively good correspondence with those of the selenite reduction assay (correspondence, 81.8%), assays for cefoperazone resistance (correspondence, 86.4%), and assays for growth at 42 degrees C (correspondence, 81.8%). The results of the glycine tolerance test and PCR completely agreed for the 103 C. fetus isolates tested. We conclude that at present the traditional phenotypic characterization of C. fetus subspecies under strongly defined conditions remains indispensable, but this PCR assay constitutes a valuable adjunctive technique for the confirmation of phenotypic results.


Asunto(s)
Técnicas de Tipificación Bacteriana , Infecciones por Campylobacter/veterinaria , Campylobacter fetus/clasificación , Enfermedades de los Bovinos/microbiología , Reacción en Cadena de la Polimerasa/métodos , Animales , Infecciones por Campylobacter/microbiología , Campylobacter fetus/efectos de los fármacos , Campylobacter fetus/genética , Bovinos , Medios de Cultivo , ADN Bacteriano/análisis , Femenino , Glicina/farmacología , Fenotipo , Selenito de Sodio/metabolismo , Especificidad de la Especie
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA