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1.
Ultrasound Obstet Gynecol ; 62(1): 42-60, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36370446

RESUMEN

The uterine junctional zone is the subendometrial area in the myometrium that contributes to peristalsis and aids in spermatozoa and blastocyst transport. Alterations in the appearance of the junctional zone on transvaginal sonography (TVS) or magnetic resonance imaging (MRI) are associated with adenomyosis. The lack of standardization of description of its appearance and ill-defined boundaries on both histology and imaging hamper understanding of the junctional zone and limit its role in the diagnosis of adenomyosis. The objectives of this review were to investigate the accordance in definition of the junctional zone across different diagnostic approaches and to examine how imaging findings can be linked to histological findings in the context of diagnosis of adenomyosis. A comprehensive literature review was conducted of articles describing the appearance on imaging and the histological structure of the uterine junctional zone. Our review suggests that the junctional zone is distinguished from the middle and outer myometrium by gradual changes in smooth-muscle cell density, extracellular space, connective tissue, water content and vascular properties. However, while the signal intensity from the junctional zone to the middle myometrium changes abruptly on MRI, the histopathological changes are gradual and its border may be difficult or impossible to distinguish on two-dimensional TVS. Moreover, the thickness of the junctional zone measured on MRI is larger than that measured on TVS. Thus, these two imaging modalities reflect this zone differently. Although a thickened junctional zone is often used to diagnose adenomyosis on MRI, the presence of adenomyosis can be described more accurately as interruptions of the junctional zone by endometrial tissue, which leads to direct signs on imaging such as subendometrial lines and buds on two- and three-dimensional TVS or bright foci on MRI. The histopathological criteria for diagnosis are based on enlargement of the uterus with severe adenomyosis, and might not reflect its early stages. Clinicians should be aware that findings on MRI cannot be extrapolated readily to ultrasound. An understanding of this is necessary when investigating the uterine junctional zone as a functional unit and the association between visualization of direct features of adenomyosis in the junctional zone and clinical symptoms. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Adenomiosis , Endometriosis , Embarazo , Femenino , Humanos , Adenomiosis/diagnóstico , Útero/diagnóstico por imagen , Útero/patología , Miometrio/diagnóstico por imagen , Miometrio/patología , Ultrasonografía/métodos , Imagen por Resonancia Magnética/métodos , Endometriosis/patología
2.
Ultrasound Obstet Gynecol ; 60(1): 118-131, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-34587658

RESUMEN

OBJECTIVES: To evaluate whether the Morphological Uterus Sonographic Assessment (MUSA) features of adenomyosis need to be better defined and, if deemed necessary, to reach consensus on the updated definitions. METHODS: A modified Delphi procedure was performed among European gynecologists with expertise in ultrasound diagnosis of adenomyosis. To identify MUSA features that might need revision, 15 two-dimensional (2D) video recordings (four recordings also included three-dimensional (3D) still images) of transvaginal ultrasound (TVS) examinations of the uterus were presented in the first Delphi round (online questionnaire). Experts were asked to confirm or refute the presence of each of the nine MUSA features of adenomyosis (described in the original MUSA consensus statement) in each of the 15 videoclips and to provide comments. In the second Delphi round (online questionnaire), the results of the first round and suggestions for revision of MUSA features were shared with the experts before they were asked to assess a new set of 2D and 3D still images of TVS examinations and to provide feedback on the proposed revisions. A third Delphi round (virtual group meeting) was conducted to discuss and reach final consensus on revised definitions of MUSA features. Consensus was predefined as at least 66.7% agreement between experts. RESULTS: Of 18 invited experts, 16 agreed to participate in the Delphi procedure. Eleven experts completed and four experts partly finished the first round. The experts identified a need for more detailed definitions of some MUSA features. They recommended use of 3D ultrasound to optimize visualization of the junctional zone. Fifteen experts participated in the second round and reached consensus on the presence or absence of ultrasound features of adenomyosis in most of the still images. Consensus was reached for all revised definitions except those for subendometrial lines and buds and interrupted junctional zone. Thirteen experts joined the online meeting, in which they discussed and agreed on final revisions of the MUSA definitions. There was consensus on the need to distinguish between direct features of adenomyosis, i.e. features indicating presence of ectopic endometrial tissue in the myometrium, and indirect features, i.e. features reflecting changes in the myometrium secondary to presence of endometrial tissue in the myometrium. Myometrial cysts, hyperechogenic islands and echogenic subendometrial lines and buds were classified unanimously as direct features of adenomyosis. Globular uterus, asymmetrical myometrial thickening, fan-shaped shadowing, translesional vascularity, irregular junctional zone and interrupted junctional zone were classified as indirect features of adenomyosis. CONCLUSION: Consensus between gynecologists with expertise in ultrasound diagnosis of adenomyosis was achieved regarding revised definitions of the MUSA features of adenomyosis and on the classification of MUSA features as direct or indirect signs of adenomyosis. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Adenomiosis , Musa , Adenomiosis/diagnóstico por imagen , Técnica Delphi , Femenino , Humanos , Miometrio/diagnóstico por imagen , Embarazo , Ultrasonografía/métodos , Útero/diagnóstico por imagen
3.
Am J Physiol Lung Cell Mol Physiol ; 318(4): L698-L704, 2020 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-32048864

RESUMEN

Chronic lung diseases such as idiopathic pulmonary fibrosis (IPF) and chronic obstructive pulmonary disease (COPD) are associated with changes in extracellular matrix (ECM) composition and abundance affecting the mechanical properties of the lung. This study aimed to generate ECM hydrogels from control, severe COPD [Global Initiative for Chronic Obstructive Lung Disease (GOLD) IV], and fibrotic human lung tissue and evaluate whether their stiffness and viscoelastic properties were reflective of native tissue. For hydrogel generation, control, COPD GOLD IV, and fibrotic human lung tissues were decellularized, lyophilized, ground into powder, porcine pepsin solubilized, buffered with PBS, and gelled at 37°C. Rheological properties from tissues and hydrogels were assessed with a low-load compression tester measuring the stiffness and viscoelastic properties in terms of a generalized Maxwell model representing phases of viscoelastic relaxation. The ECM hydrogels had a greater stress relaxation than tissues. ECM hydrogels required three Maxwell elements with slightly faster relaxation times (τ) than that of native tissue, which required four elements. The relative importance (Ri) of the first Maxwell element contributed the most in ECM hydrogels, whereas for tissue the contribution was spread over all four elements. IPF tissue had a longer-lasting fourth element with a higher Ri than the other tissues, and IPF ECM hydrogels did require a fourth Maxwell element, in contrast to all other ECM hydrogels. This study shows that hydrogels composed of native human lung ECM can be generated. Stiffness of ECM hydrogels resembled that of whole tissue, while viscoelasticity differed.


Asunto(s)
Matriz Extracelular/metabolismo , Hidrogeles/metabolismo , Pulmón/metabolismo , Pulmón/fisiología , Rigidez Vascular/fisiología , Animales , Humanos , Fibrosis Pulmonar Idiopática/metabolismo , Fibrosis Pulmonar Idiopática/patología , Pepsina A/metabolismo , Enfermedad Pulmonar Obstructiva Crónica/metabolismo , Enfermedad Pulmonar Obstructiva Crónica/patología , Porcinos , Viscosidad
4.
Gynecol Oncol ; 155(2): 213-219, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31477282

RESUMEN

OBJECTIVE: Optimizing the counselling of women ≤40years with epithelial ovarian cancer (EOC) by investigating the role of young age and tumour characteristics on overall survival (OS). METHODS: A retrospective population-based study was done using data of EOC patients diagnosed between 1990 and 2014 registered in the Netherlands Cancer Registry. Descriptive statistics were performed to analyse clinical and tumour characteristics. Five- and 10-year OS rates were calculated using Kaplan Meier curves. To determine prognostic factors, univariable and multivariable survival analyses were performed. RESULTS: 1407 women ≤40years and 29,022 women >40years old were included. OS was higher for the younger women compared to older group (5-year survival of 65.6% vs. 32.7%, 10-year survival of 57.5% vs. 22.5%, respectively). The younger women had more often a mucinous (36.4%), well-differentiated (31.8%) tumour in early stage of disease (49.9%). Serous tumours (43.0%), high-grade (36.0%) and stage III (47.1%) were most frequently found in the older women. Histology, grade, stage, incidence year, and age group are independent prognostic factors for survival. OS of the young women for several combinations of tumour characteristics were calculated. CONCLUSIONS: Age is an independent prognostic factor for OS in EOC patients. Counselling on prognosis could be more individualised in young EOC patients using the tumour characteristics histology, stage and grade.


Asunto(s)
Carcinoma Epitelial de Ovario/mortalidad , Neoplasias Ováricas/mortalidad , Adulto , Distribución por Edad , Anciano , Carcinoma Epitelial de Ovario/patología , Consejo , Femenino , Humanos , Estimación de Kaplan-Meier , Persona de Mediana Edad , Países Bajos/epidemiología , Neoplasias Ováricas/patología , Pronóstico , Sistema de Registros , Estudios Retrospectivos
5.
Gynecol Oncol ; 143(1): 113-119, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27430397

RESUMEN

OBJECTIVE: Risk-reducing salpingo-oophorectomy (RRSO) is the only effective surgical strategy to reduce the increased risk of epithelial ovarian cancer in BRCA1/2 mutation carriers. Given the long-term health consequences of premature surgical menopause, we need insight in uptake and timing of RRSO to guide us in improving healthcare. METHODS: A single-center retrospective cohort study of BRCA1/2 mutation carriers diagnosed and counseled at the multidisciplinary Family Cancer Clinic of the Radboud university medical center in Nijmegen, The Netherlands, between 1999 and 2014. Descriptive statistics were used to analyze uptake and timing of RRSO. RESULTS: Data of 580 BRCA1/2 were analyzed. The uptake of RRSO among mutation carriers who are currently above the upper limit of the recommended age for RRSO, is 98.5% and 97.5% for BRCA1 and BRCA2 mutation carriers, respectively. The vast majority undergoes RRSO ≤40 (BRCA1) or ≤45 (BRCA2) years of age, provided that mutation status is known by that age: 90.8% and 97.3% of BRCA1 and BRCA2 mutation carriers, respectively. CONCLUSIONS: The uptake of RRSO among BRCA1/2 mutation carriers who were counseled at our Family Cancer Clinic is extremely high. High uptake might be largely attributed to the directive and uniform way of counseling by professionals at our Family Cancer Clinic. Given the fact that RRSO is often undergone at premenopausal age in our population, future research should focus on minimizing long-term health consequences of premature surgical menopause either by optimization of hormone replacement therapy or by investigating alternative strategies to RRSO.


Asunto(s)
Genes BRCA1 , Genes BRCA2 , Heterocigoto , Mutación , Neoplasias Glandulares y Epiteliales/prevención & control , Neoplasias Ováricas/prevención & control , Ovariectomía , Salpingectomía , Adolescente , Adulto , Anciano , Carcinoma Epitelial de Ovario , Femenino , Humanos , Persona de Mediana Edad , Neoplasias Glandulares y Epiteliales/genética , Neoplasias Ováricas/genética , Estudios Retrospectivos , Conducta de Reducción del Riesgo
6.
Tissue Eng Regen Med ; 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38976146

RESUMEN

BACKGROUND: The extracellular vesicles (EVs) secreted by adipose tissue-derived stromal cells (ASC) are microenvironment modulators in tissue regeneration by releasing their molecular cargo, including miRNAs. However, the influence of ASC-derived extracellular vesicles (ASC-EVs) on endothelial cells (ECs) and vascularisation is poorly understood. The present study aimed to determine the pro-angiogenic effects of ASC-EVs and explore their miRNA profile. METHODS: EVs were isolated from normoxic and hypoxic cultured ASC conditioned culture medium. The miRNA expression profile was determined by miRseq, and EV markers were determined by Western blot and immunofluorescence staining. The uptake dynamics of fluorescently labelled EVs were monitored for 24 h. ASC-EVs' pro-angiogenic effect was assessed by sprouting ex vivo rat aorta rings in left ventricular-decellularized extracellular matrix (LV dECM) hydrogel or basement membrane hydrogel (Geltrex®). RESULTS: ASC-EVs augmented vascular network formation by aorta rings. The vascular network topology and stability were influenced in a hydrogel scaffold-dependent fashion. The ASC-EVs were enriched for several miRNA families/clusters, including Let-7 and miR-23/27/24. The miRNA-1290 was the highest enriched non-clustered miRNA, accounting for almost 20% of all reads in hypoxia EVs. CONCLUSION: Our study revealed that ASC-EVs augment in vitro and ex vivo vascularisation, likely due to the enriched pro-angiogenic miRNAs in EVs, particularly miR-1290. Our results show promise for regenerative and revascularisation therapies based on ASC-EV-loaded ECM hydrogels.

7.
Vascul Pharmacol ; 154: 107276, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38242295

RESUMEN

INTRODUCTION: Cancer needs perfusion for its growth and metastasis. Cancer cell-derived extracellular vesicles (CA-EVs) alter the tumor microenvironment (TME), potentially promoting angiogenesis. We hypothesize that conditions in the tumor, e.g., hypoxia, and in the target cells of the TME, e.g., nutrient deprivation or extracellular matrix, can affect the angiogenic potential of CA-EVs, which would contribute to explaining the regulation of tumor vascularization and its influence on cancer growth and metastasis. METHODS: CA-EVs were isolated and characterized from cervical carcinoma cell lines HeLa and SiHa cultured under normoxia and hypoxia, and their angiogenic potential was evaluated in vitro in three endothelial cells (ECs) lines and aortic rings, cultured in basal (growth factor-reduced) or complete medium. RESULTS: Hypoxia increased EV production 10-100 times and protein content 2-4 times compared to normoxic CA-EVs. HeLa-EVs contained six times more RNA than SiHa-EVs, and this concentration was not affected by hypoxia. Treatment with CA-EVs increased tube formation and sprouting in ECs and aortic rings cultured in basal medium and long-term stabilized the stablished vascular networks formed by ECs cultured in complete medium. CONCLUSION: Hypoxia differentially affects CA-EVs in a cell line-dependent manner. The cellular environment (nutrient availability and extracellular matrix scaffold) influences the effect of CA-EV on the angiogenic potential of ECs.


Asunto(s)
Carcinoma , Vesículas Extracelulares , Humanos , Células Endoteliales/metabolismo , Angiogénesis , Vesículas Extracelulares/metabolismo , Carcinoma/metabolismo , Carcinoma/patología , Hipoxia/metabolismo , Microambiente Tumoral
8.
J Virol ; 86(22): 12341-50, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22951840

RESUMEN

Influenza viruses unable to express NS1 protein (delNS1) replicate poorly and induce large amounts of interferon (IFN). They are therefore considered candidate viruses for live-attenuated influenza vaccines. Their attenuated replication is generally assumed to result from the inability to counter the antiviral host response, as delNS1 viruses replicate efficiently in Vero cells, which lack IFN expression. In this study, delNS1 virus was parallel passaged on IFN-competent MDCK cells, which resulted in two strains that were able to replicate to high virus titers in MDCK cells due to adaptive mutations especially in the M-gene segment but also in the NP and NS gene segments. Most notable were clustered U-to-C mutations in the M segment of both strains and clustered A-to-G mutations in the NS segment of one strain, which presumably resulted from host cell-mediated RNA editing. The M segment mutations in both strains changed the ratio of M1 to M2 expression, probably by affecting splicing efficiency. In one virus, 2 amino acid substitutions in M1 additionally enhanced virus replication, possibly through changes in the M1 distribution between the nucleus and the cytoplasm. Both adapted viruses induced levels of IFN equal to that of the original delNS1 virus. These results show that the increased replication of the adapted viruses is not primarily due to altered IFN induction but rather is related to changes in M1 expression or localization. The mutations identified in this paper may be used to enhance delNS1 virus replication for vaccine production.


Asunto(s)
Virus de la Influenza A/genética , Proteínas no Estructurales Virales/metabolismo , Animales , Apoptosis , Secuencia de Bases , Chlorocebus aethiops , Perros , Genoma Viral , Humanos , Vacunas contra la Influenza/metabolismo , Células de Riñón Canino Madin Darby , Datos de Secuencia Molecular , Mutación , Análisis de Secuencia de ADN , Células Vero , Proteínas no Estructurales Virales/química , Proteínas no Estructurales Virales/genética , Replicación Viral
9.
Transl Oncol ; 31: 101633, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36905871

RESUMEN

Vascularization is a multifactorial and spatiotemporally regulated process, essential for cell and tissue survival. Vascular alterations have repercussions on the development and progression of diseases such as cancer, cardiovascular diseases, and diabetes, which are the leading causes of death worldwide. Additionally, vascularization continues to be a challenge for tissue engineering and regenerative medicine. Hence, vascularization is the center of interest for physiology, pathophysiology, and therapeutic processes. Within vascularization, phosphatase and tensin homolog deleted on chromosome 10 (PTEN) and Hippo signaling have pivotal roles in the development and homeostasis of the vascular system. Their suppression is related to several pathologies, including developmental defects and cancer. Non-coding RNAs (ncRNAs) are among the regulators of PTEN and/or Hippo pathways during development and disease. The purpose of this paper is to review and discuss the mechanisms by which exosome-derived ncRNAs modulate endothelial cell plasticity during physiological and pathological angiogenesis, through the regulation of PTEN and Hippo pathways, aiming to establish new perspectives on cellular communication during tumoral and regenerative vascularization.

10.
Eur Cell Mater ; 24: 320-330, 2012 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-23070944

RESUMEN

An array of different types of hyaluronic acid (HA)- and collagen-based products is available for filling soft-tissue defects. A major drawback of the current soft-tissue fillers is their inability to induce cell infiltration and new tissue formation. Our aim is to develop novel biodegradable injectable gels which induce soft tissue regeneration, initially resulting in integration and finally replacement of the gel with new autologous tissue. Two reference gels of pure HA, monophasic HA-1 and micronised HA-2, were used. Furthermore, both gels were mixed with recombinant gelatin (RG) resulting in HA-1+RG and HA-2+RG. All gels were subcutaneously injected on the back of rats and explanted after 4 weeks. Addition of RG to HA-1 resulted in stroma formation (neovascularisation and ECM deposition) which was restricted to the outer rim of the HA-1+RG gel. In contrast, addition of RG to HA-2 induced stroma formation throughout the gel. The RG component of the gel was degraded by macrophages and giant cells and subsequently replaced by new vascularised tissue. Immunohistochemical staining showed that the extracellular matrix components collagen I and III were deposited throughout the gel. In conclusion, this study shows the proof of principle that addition of RG to HA-2 results in a novel injectable gel capable of inducing soft tissue regeneration. In this gel HA has a scaffold function whereas the RG component induces new tissue formation, resulting in proper vascularisation and integration of the HA-2+RG gel with the autologous tissue.


Asunto(s)
Gelatina/química , Ácido Hialurónico/química , Regeneración , Tejido Subcutáneo/fisiología , Andamios del Tejido/química , Animales , Gelatina/genética , Geles/química , Masculino , Ratas , Proteínas Recombinantes/química
11.
Sci Rep ; 11(1): 13493, 2021 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-34188159

RESUMEN

The rate of the remodeling of the arterialized saphenous vein conduit limits the outcomes of coronary artery bypass graft surgery (CABG), which may be influenced by endothelial dysfunction. We tested the hypothesis that high stretch (HS) induces human saphenous vein endothelial cell (hSVEC) dysfunction and examined candidate underlying mechanisms. Our results showed that in vitro HS reduces NO bioavailability, increases inflammatory adhesion molecule expression (E-selectin and VCAM1) and THP-1 cell adhesion. HS decreases F-actin in hSVECs, but not in human arterial endothelial cells, and is accompanied by G-actin and cofilin's nuclear shuttling and increased reactive oxidative species (ROS). Pre-treatment with the broad-acting antioxidant N-acetylcysteine (NAC) supported this observation and diminished stretch-induced actin remodeling and inflammatory adhesive molecule expression. Altogether, we provide evidence that increased oxidative stress and actin cytoskeleton remodeling play a role in HS-induced saphenous vein endothelial cell dysfunction, which may contribute to predisposing saphenous vein graft to failure.


Asunto(s)
Actinas/metabolismo , Células Endoteliales/metabolismo , Estrés Oxidativo , Vena Safena/metabolismo , Estrés Mecánico , Humanos , Especies Reactivas de Oxígeno/metabolismo , Células THP-1
12.
Eur Cell Mater ; 20: 197-209, 2010 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-20931490

RESUMEN

Subcutaneously implanted disks of hexamethylenediisocyanate or glutaraldehyde cross-linked sheep collagen (referred to as HDSC and GDSC, respectively) in mice show large differences in degradation rate. Although comparable numbers of macrophages are seen in HDSC and GDSC, phagocytosis of collagen by macrophages occurred only in GDSC. The molecular mechanisms involved in the phagocytosis of collagen by macrophages are essentially unknown. Immunofluorescence and RT-PCR showed that Endo180 was expressed in GDSC only. TissueFaxs showed that Endo180 co-localized with MT1-MMP on F4÷80 positive cells, which is likely responsible for the phagocytosis in GDSC. RT-PCR further showed that Endo180 expression correlated with high levels of IFN-γ mRNA. In vitro, IFN-γ induced the expression Endo180 and MT1-MMP in murine macrophages cultured on collagen type I (although too high levels of IFN-γ dampened the expression of Endo180 and MT1-MMP). Moreover, the expression of Endo180 and MT1-MMP induced by IFN-γ can be inhibited through IL-10. The differences in microenvironment between GDSC and HDSC (high IFN-γ and low IL-10 levels in GDSC, low IFN-γ and high IL-10 levels in HDSC) provide an explanation why phagocytosis of collagen by macrophages is only seen in GDSC. In summary, we show for the first time that the IFN-γ dependent co-expression of Endo180 and MT1-MMP on macrophages coincides with collagen phagocytosis, thus providing evidence that the mechanism of collagen phagocytosis operating in the foreign body reaction by macrophages is comparable with the mechanism of intracellular collagen degradation by fibroblasts seen under physiological conditions.


Asunto(s)
Colágeno/metabolismo , Interferón gamma/metabolismo , Macrófagos/metabolismo , Metaloproteinasa 14 de la Matriz/metabolismo , Fagocitosis/fisiología , Receptores Mitogénicos/metabolismo , Andamios del Tejido , Animales , Interleucina-10/metabolismo , Macrófagos/citología , Ratones , Ratones Endogámicos C57BL , Microscopía Fluorescente , Ovinos
13.
Ned Tijdschr Tandheelkd ; 117(12): 628-36, 2010 Dec.
Artículo en Holandés | MEDLINE | ID: mdl-21298891

RESUMEN

In recent years various studies have been published which indicate that adverse events in health care facilities are the result of structural factors. In 2009 a national study was carried out in the Netherlands to gain insight into patient safety in primary care settings, including general dental practices. In 20 randomly selected practices, patient records were investigated and oral care professionals reported, during a period of 2 weeks, adverse events which occurred. For each practice, 2 researchers screened, with the help of a checklist, 50 randomly selected patient records covering a period of 1 year. A total of 8 preventable adverse events were found in the 1000 patient records (0.8%). Anonymous reports made during the 2 weeks of the research period resulted in 7 adverse events. Practically all of the adverse events had to do with diagnostics and treatment and resulted in limited harmful consequences for patients. On the basis of these results, oral care in general dental practice would appear to be safe, but the concept 'patient safety' is not at all or only minimally active among general dental practitioners. Regarding patient safety performance, improvement in the quality of record-keeping would be desirable.


Asunto(s)
Odontología/normas , Control de Formularios y Registros/normas , Satisfacción del Paciente , Humanos , Países Bajos , Administración de la Seguridad
14.
J Cell Mol Med ; 13(8B): 2521-2533, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18752636

RESUMEN

Neovascularization by endothelial progenitor cells (EPC) for the treatment of ischaemic diseases has been a topic of intense research. The CD34(+) cell is often designated as EPC, because it contributes to repair of ischaemic injuries through neovascularization. However, incorporation of CD34(+) cells into the neovasculature is limited, suggesting another role which could be paracrine. CD14(+) cells can also differentiate into endothelial cells and contribute to neovascularization. However, the low proliferative capacity of CD14(+) cell-derived endothelial cells hampers their use as therapeutic cells. We made the assumption that an interaction between CD34(+) and CD14(+) cells augments endothelial differentiation of the CD14(+) cells. In vitro, the influence of CD34(+) cells on the endothelial differentiation capacity of CD14(+) cells was investigated. Endothelial differentiation was analysed by expression of endothelial cell markers CD31, CD144, von Willebrand Factor and endothelial Nitric Oxide Synthase. Furthermore, we assessed proliferative capacity and endothelial cell function of the cells in culture. In monocultures, 63% of the CD14(+)-derived cells adopted an endothelial cell phenotype, whereas in CD34(+)/CD14(+) co-cultures 95% of the cells showed endothelial cell differentiation. Proliferation increased up to 12% in the CD34(+)/CD14(+) co-cultures compared to both monocultures. CD34-conditioned medium also increased endothelial differentiation of CD14(+) cells. This effect was abrogated by hepatocyte growth factor neutralizing antibodies, but not by interleukin-8 and monocyte chemoattractant protein-1 neutralizing antibodies. We show that co-culturing of CD34(+) and CD14(+) cells results in a proliferating population of functional endothelial cells, which may be suitable for treatment of ischaemic diseases such as myocardial infarction.


Asunto(s)
Antígenos CD34/inmunología , Diferenciación Celular/inmunología , Endotelio Vascular/inmunología , Receptores de Lipopolisacáridos/inmunología , Células Madre/inmunología , Técnicas de Cocultivo , Medios de Cultivo Condicionados , Endotelio Vascular/citología , Humanos , Células Madre/citología
15.
J Pathol ; 216(2): 201-8, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18702175

RESUMEN

The human epithelial cell adhesion molecule (hEpCAM) is involved in epithelial morphogenesis and repair of epithelial tissues. We hypothesized that changes in hEpCAM expression in vivo correlate with regeneration of renal epithelia after ischaemia/reperfusion injury (IRi). Unilateral IRi was performed on kidneys of hEpCAM transgenic mice. Changes in hEpCAM expression were investigated by quantitative RT-PCR in renal cortex and medulla dissected by laser dissection microscopy and expression patterns of hEpCAM in regenerating kidneys were assessed by immunohistochemistry. The mechanism of hEpCAM promoter activation was investigated in vitro, by real-time bioluminescent imaging in HK-2 cells and in primary tubular epithelial cells (PTECs) subjected to hypoxia and reoxygenation. In vivo, the transcription of the human epcam gene significantly increased in the renal cortex during tubular re-epithelialization (p < 0.01). Moreover, the number of tubuli that expressed hEpCAM protein more than doubled in the renal cortex during regeneration. De novo expression of hEpCAM was detected in the S1 segments of proximal tubuli. Under hypoxic conditions in vitro, activity of the hEpCAM promoter was up-regulated two-fold in the HK-2 proximal epithelial cell line. Moreover, both in primary proximal epithelial cells and in HK-2 cells, hEpCAM protein expression was increased after hypoxia and reoxygenation. The significant up-regulation of hEpCAM during post-ischaemic renal regeneration in vivo and during in vitro hypoxia indicates that hEpCAM expression is associated with renal regeneration.


Asunto(s)
Antígenos de Neoplasias/metabolismo , Moléculas de Adhesión Celular/metabolismo , Células Epiteliales/patología , Riñón/patología , Riñón/fisiología , Regeneración , Regulación hacia Arriba , Animales , Antígenos de Neoplasias/análisis , Antígenos de Neoplasias/genética , Moléculas de Adhesión Celular/análisis , Moléculas de Adhesión Celular/genética , Línea Celular , Molécula de Adhesión Celular Epitelial , Células Epiteliales/metabolismo , Humanos , Hipoxia/metabolismo , Hipoxia/patología , Inmunohistoquímica , Ratones , Ratones Transgénicos , Regiones Promotoras Genéticas , Daño por Reperfusión/metabolismo , Daño por Reperfusión/patología
16.
Appl Microbiol Biotechnol ; 84(6): 1087-94, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19455325

RESUMEN

Single-domain antibody fragments (VHHs) have several beneficial properties as compared to conventional antibody fragments. However, their small size complicates their toxin- and virus-neutralizing capacity. We isolated 27 VHHs binding Escherichia coli heat-labile toxin and expressed these in Saccharomyces cerevisiae. The most potent neutralizing VHH (LT109) was N-glycosylated, resulting in a large increase in molecular mass. This suggests that N-glycosylation of LT109 improves its neutralizing capacity. Indeed, deglycosylation of LT109 decreased its neutralizing capacity three- to fivefold. We also studied the effect of glycosylation of two previously isolated VHHs on their ability to neutralize foot-and-mouth disease virus. For this purpose, these VHHs that lacked potential N-glycosylation sites were genetically fused to another VHH that was known to be glycosylated. The resulting fusion proteins were also N-glycosylated. They neutralized the virus at at least fourfold-lower VHH concentrations as compared to the single, non-glycosylated VHHs and at at least 50-fold-lower VHH concentrations as compared to their deglycosylated counterparts. Thus, we have shown that N-glycosylation of VHHs contributes to toxin- and virus-neutralizing capacity.


Asunto(s)
Toxinas Bacterianas/inmunología , Enterotoxinas/inmunología , Proteínas de Escherichia coli/inmunología , Virus de la Fiebre Aftosa/inmunología , Fragmentos de Inmunoglobulinas/química , Secuencia de Aminoácidos , Animales , Anticuerpos Neutralizantes/biosíntesis , Anticuerpos Neutralizantes/química , Anticuerpos Neutralizantes/inmunología , Camélidos del Nuevo Mundo , Chlorocebus aethiops , Epítopos , Fiebre Aftosa/inmunología , Fiebre Aftosa/virología , Glicosilación , Fragmentos de Inmunoglobulinas/biosíntesis , Fragmentos de Inmunoglobulinas/inmunología , Datos de Secuencia Molecular , Proteínas Recombinantes de Fusión/biosíntesis , Proteínas Recombinantes de Fusión/inmunología , Saccharomyces cerevisiae/metabolismo , Células Vero
17.
Vet Microbiol ; 132(1-2): 56-64, 2008 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-18534789

RESUMEN

Foot-and-mouth disease (FMD) is a contagious viral disease of cloven-hoofed animals that occasionally causes outbreaks in Europe. We aim to develop an immunotherapy that confers rapid protection against FMD in outbreak situations. For this purpose, we previously isolated llama single-domain antibody fragments (VHHs) binding to FMDV or porcine immunoglobulin (pIg). The pIg binding VHHs can be genetically fused to other VHHs, resulting in so-called VHH2s. As compared to non-pIg binding VHHs such VHH2s have a 100-fold increased serum half-life which is essential for effective immunotherapy. We have now produced three bispecific VHH2s by fusion of three FMDV binding VHHs (clones M3, M8 and M23) to a pIg binding VHH (VI-4). The resulting yeast-produced VHH2s bound FMDV and pIg with high affinity (K(D) about 1nM) and neutralized FMDV in vitro as efficiently as their monovalent counterparts. To evaluate their therapeutic potential all three VHH2s were intramuscularly injected into pigs that were challenge infected with FMDV 24h later. Administration of one of these VHH2s (M23ggsVI-4) reduced the viremia significantly (P=0.0034) and reduced viral shedding almost significantly (P=0.11). However, it did not prevent development of clinical signs or transmission of FMDV. These results suggest that immunotherapy using bispecific VHH2s binding to FMDV and pIg is possible in principle, but should be improved by increasing VHH2 dosage or using more potent VHH2s.


Asunto(s)
Anticuerpos Antivirales/inmunología , Camélidos del Nuevo Mundo/inmunología , Virus de la Fiebre Aftosa/inmunología , Fiebre Aftosa/inmunología , Inmunoglobulinas/inmunología , Enfermedades de los Porcinos/prevención & control , Animales , Inmunización Pasiva , Porcinos
19.
Clin Microbiol Infect ; 24(12): 1273-1279, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30036665

RESUMEN

SCOPE: Antimicrobial stewardship teams are responsible for implementing antimicrobial stewardship programmes (ASP). However, in many countries, lack of funding challenges this obligation. A consensus procedure was performed to investigate which structural activities need to be performed by Dutch stewardship teams and how much time (and thus full-time equivalent (FTE) labor) is needed to perform these activities. METHODS: In 2015, an electronic survey, based on a nonsystematic literature search and interviews with seven experienced stewardship teams, was sent to 21 stewardship teams that performed an ASP. This was followed by a semistructured face-to-face consensus meeting. Fourteen stewardship teams completed the survey (18% of Dutch acute-care hospitals), and 13 participated in the consensus meeting. RECOMMENDATIONS: The hours needed each year are dependent on hospital size and number of stewardship objectives monitored. If all activities are performed at a minimal base (one stewardship objective; minimal staffing standard), time investment was estimated to be 1393 to 2680 hours annually in the early phase, corresponding with 0.87 (300 beds) to 1.68 FTE (1200 beds), with a further increase to minimally 1.25 to 3.18 FTE in the following years with three stewardship objectives monitored (optimal staffing standards during the first few years of implementing an ASP). This consensus on required human resources provides a directive for structural financial support of stewardship teams in the Dutch context. Some stewardship activities (and related time investments) might be specific to the Dutch context and hospital setting. To develop standards for other settings, our methodology could be applied.


Asunto(s)
Programas de Optimización del Uso de los Antimicrobianos , Consenso , Recursos Humanos/economía , Antibacterianos/uso terapéutico , Hospitales/estadística & datos numéricos , Humanos , Países Bajos , Encuestas y Cuestionarios
20.
J Biomed Mater Res A ; 106(9): 2494-2506, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29700983

RESUMEN

Abdominal aortic aneurysm (AAA) is the pathological dilation and weakening of the abdominal aorta wall. Inflammation, degradation of the extracellular matrix (ECM) and loss of smooth muscle cells and skewing of their function are pivotal in AAA pathology. We developed a recombinant collagen-based patch (RCP) to provide structural integrity and deliver Adipose tissue-Derived Stromal Cells (ASC) for repair. Patches supported adhesion and function as well as proliferation of ASC. ASC-loaded RCPs or bare patches, applied around the aorta after AAA induction in rats, both maintained structural integrity of the aortic wall at time of explant (2w). However, wall thinning, accompanied by loss of elastin fibers and loss of medial SMC, was only attenuated in ASC-loaded RCP-treated AAA rats. Interestingly, this coincided with migration of ASC into the media and a reduced influx of macrophages. We hypothesize that the medially-migrated ASC dampened or skewed the adverse innate immunity and thus suppressed SMC apoptosis, phenotypic skewing and elastin degradation. We conclude that the periadventitial delivery of ASC with RCP suppresses development and progression of AAA, which is has an expected future clinical benefit in combination with an appropriate early screening program of patients at risk for aneurysms. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A:2494-2506, 2018.


Asunto(s)
Tejido Adiposo/citología , Aneurisma de la Aorta Abdominal/terapia , Vasos Sanguíneos/fisiología , Andamios del Tejido/química , Animales , Aorta Abdominal/patología , Aneurisma de la Aorta Abdominal/patología , Vasos Sanguíneos/efectos de los fármacos , Adhesión Celular/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Medios de Cultivo Condicionados/farmacología , Dilatación , Elastina/metabolismo , Humanos , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Masculino , Miocitos del Músculo Liso/efectos de los fármacos , Miocitos del Músculo Liso/patología , Proteolisis/efectos de los fármacos , Ratas Endogámicas F344 , Proteínas Recombinantes/farmacología , Células del Estroma/citología , Propiedades de Superficie , Cicatrización de Heridas/efectos de los fármacos
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