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1.
Arch Phys Med Rehabil ; 104(8): 1268-1273, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36893878

RESUMEN

OBJECTIVE: To identify the extent and quality of fine motor skill alteration in patients with Dupuytren disease (DD) using an instrumented device measuring grip forces, beyond the commonly used measurement of contracture. DESIGN: Case-control study. SETTING: University outpatient clinic. PARTICIPANTS: Patients with DD (N=27) and a contracture >45° (Tubiana stage II, III, and IV) were included and compared with age-matched healthy control patients (N=27). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES(S): All individuals were subjected to a set of specific tests using a new instrumented device ("manipulandum"). These included lifting, grasping, and then holding the "manipulandum" with 4 different object characteristics (light and heavy weight, rough and smooth surface) along with a measurement of the precision grip strength. Standard measurements including the Nine-Hole Peg Test, a two-point discrimination, and the Disability of Arm, Shoulder and Hand score were evaluated in comparison. RESULTS: Although the measurements of precision grip, two-point discrimination, Nine-Hole Peg Test, and Disability of Arm, Shoulder and Hand score showed no statistically significant differences between both groups, patients with DD applied significantly greater forces when tested with the different subtests using the "manipulandum." Analysis of the 2-phase movement (lifting and holding the "manipulandum") revealed highly significant differences between the groups. CONCLUSIONS: Patients with DD use excessive grip forces when lifting and holding the "manipulandum" when compared with healthy control patients, independent of the degree of contracture. As no differences in precision grip strength were seen, the presented approach is useful to obtain additional important information about fine motor function in diseased hands.


Asunto(s)
Contractura de Dupuytren , Humanos , Elevación , Estudios de Casos y Controles , Mano , Fuerza de la Mano , Desempeño Psicomotor
2.
Int J Mol Sci ; 21(3)2020 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-32041245

RESUMEN

The application of liposuctioned white adipose tissue (L-WAT) and adipose-derived stem cells (ADSCs) as a novel immunomodulatory treatment option is the currently subject of various clinical trials. Because it is crucial to understand the underlying therapeutic mechanisms, the latest studies focused on the immunomodulatory functions of L-WAT or ADSCs. However, studies that examine the specific transcriptional adaptation of these treatment options to an extrinsic inflammatory stimulus in an unbiased manner are scarce. The aim of this study was to compare the gene expression profile of L-WAT and ADSCs, when subjected to tumor necrosis factor alpha (TNFα), and to identify key factors that might be therapeutically relevant when using L-WAT or ADSCs as an immuno-modulator. Fat tissue was harvested by liposuction from five human donors. ADSCs were isolated from the same donors and shortly subjected to expansion culture. L-WAT and ADSCs were treated with human recombinant TNFα, to trigger a strong inflammatory response. Subsequently, an mRNA deep nextgeneration sequencing was performed to evaluate the different inflammatory responses of L-WAT and ADSCs. We found significant gene expression changes in both experimental groups after TNFα incubation. However, ADSCs showed a more homogenous gene expression profile by predominantly expressing genes involved in immunomodulatory processes such as CCL19, CCL5, TNFSF15 and IL1b when compared to L-WAT, which reacted rather heterogeneously. As RNA sequencing between L-WAT and ADSCS treated with TNFα revealed that L-WAT responded very heterogeneously to TNFα treatment, we therefore conclude that ADSCs are more reliable and predictable when used therapeutically. Our study furthermore yields insight into potential biological processes regarding immune system response, inflammatory response, and cell activation. Our results can help to better understand the different immunomodulatory effects of L-WAT and ADSCs.


Asunto(s)
Adipocitos/metabolismo , Tejido Adiposo Blanco/metabolismo , Células Madre Mesenquimatosas/inmunología , Células Madre Mesenquimatosas/metabolismo , Factor de Necrosis Tumoral alfa/farmacología , Adipocitos/citología , Tejido Adiposo Blanco/citología , Quimiocina CCL19/metabolismo , Quimiocina CCL5/metabolismo , Perfilación de la Expresión Génica , Humanos , Inmunoterapia Adoptiva , Inflamación/inmunología , Interleucina-1beta/metabolismo , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/citología , Transcriptoma/genética , Miembro 15 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral/metabolismo
3.
BMC Musculoskelet Disord ; 15: 202, 2014 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-24925068

RESUMEN

BACKGROUND: Distal radius fractures (DRF) are often referred to as osteoporosis indicator fractures as their incidence increases from age 45. In the group of young adults, distal radius fractures normally result from high-energy trauma. Wrist fractures in young patients without adequate trauma thus raise suspicion of a pathologic fracture. In this report we present the case of a fractured unicameral bone cyst (UBC) at the distal radius in a young adult.To the author's best knowledge, this is the first detailed report in an UBC at the distal radius causing a pathologic DRF in an adult patient. CASE PRESENTATION: A 25-year-old otherwise healthy male presented to our Emergency Department after a simple fall on his right outstretched hand. Extended diagnostics revealed a pathologic, dorsally displaced, intra-articular distal radius fracture secondary to a unicameral bone cyst occupying almost the whole metaphysis of the distal radius. To stabilize the fracture, a combined dorsal and volar approach was used for open reduction and internal fixation. A tissue specimen for histopathological examination was gathered and the lesion was filled with an autologous bone graft harvested from the ipsilateral femur using a reamer-irrigator-aspirator (RIA) system. Following one revision surgery due to an intra-articular step-off, the patient recovered without further complications. CONCLUSIONS: Pathologic fractures in young patients caused by unicameral bone cysts require extended diagnostics and adequate treatment. A single step surgical treatment is reasonable if fracture and bone cyst are treated appropriately. Arthroscopically assisted fracture repair may be considered in intra-articular fractures or whenever co-pathologies of the carpus are suspected.


Asunto(s)
Quistes Óseos/complicaciones , Fracturas Espontáneas/etiología , Fracturas del Radio/etiología , Accidentes por Caídas , Adulto , Quistes Óseos/diagnóstico , Quistes Óseos/diagnóstico por imagen , Quistes Óseos Aneurismáticos/diagnóstico , Neoplasias Óseas/diagnóstico , Placas Óseas , Trasplante Óseo , Diagnóstico Diferencial , Fijación Interna de Fracturas/métodos , Fracturas Espontáneas/diagnóstico por imagen , Fracturas Espontáneas/cirugía , Humanos , Masculino , Fracturas del Radio/cirugía , Reoperación , Tomografía Computarizada por Rayos X
4.
J Clin Med ; 13(13)2024 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-38999536

RESUMEN

Background: Ulnar impaction syndrome (UIS) is a common degenerative wrist condition which results from positive ulnar variance, leading to an overload on the ulnar carpus. Ulnar shortening osteotomy (USO) and the arthroscopic wafer procedure (AWP) are established therapies for UIS if conservative management fails. This study assessed an algorithm-guided treatment of UIS over a period of 10 years. Methods: This prospective observational study compared the outcome of 54 patients who underwent either USO or AWP for UIS based on a predefined treatment algorithm. The mean follow-up period was 10 years. Primary outcome parameters were the visual analogue scale (VAS) for pain and the Disabilities of the Arm, Shoulder, and Hand questionnaire (DASH), whereas secondary outcome parameters were grip and pinch strength and range of motion. Results: The median preoperative ulnar variance was 2.6 mm in the USO group and 2.0 mm in the AWP group. The postoperative average ulnar variance was 0 mm in both groups. The preoperative pain at rest was 3.4 in the USO group and 2.3 in the AWP group. One year after surgery, there was a significant reduction to VAS 0.7 and 0.2, respectively. These results persisted to the 10-year follow-up (VAS 0.9 and 0.2). The pain in motion also decreased significantly in the first year (from 6.8 and 6.7 to 2.2 and 2.1), as well as after 10 years (2.4 and 1.0). The preoperative DASH score averaged 31.3 in the USO group and 35.8 in the AWP group. At the 10-year follow-up, the DASH of both groups decreased significantly to 4.35 in the AWP group compared to 12.7 in the USO group. Conclusions: Our data show that, when using our algorithm, both USO and AWP, two common operative treatment options of UIS, reliably reduce pain and significantly reduce the DASH score over at least a period of ten years. The results after 10 years differ from short-term results in so far as after one year, the USO group showed to some degree similar outcome parameters compared to AWP, whereas at the 10-year follow-up, AWP reached slightly better primary outcome parameters. The algorithm presented, thus, produced excellent short- and long-term outcomes. Our findings and the applied algorithm can assist in decision-making and patient education.

5.
Handchir Mikrochir Plast Chir ; 56(3): 250-256, 2024 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-38657620

RESUMEN

BACKGROUND: Wrist arthroscopy is a standard procedure in hand surgery for the diagnosis and treatment of wrist conditions. While perioperative antibiotic prophylaxis (PAP) is not generally recommended for elective hand surgery, there is no official standard for elective wrist arthroscopy. This study aimed to determine the actual clinical use of PAP in elective wrist arthroscopy in Germany and relate it to the structural conditions of clinics performing this procedure. MATERIAL AND METHODS: We conducted a systematic search of all facilities in Germany offering wrist arthroscopy. Among these, we performed an online survey using the SoSci Survey online tool via email. RESULTS: PAP is more frequently administered in cases involving simultaneous bone procedures. Cephalosporins are the most commonly used antibiotics in cases of PAP administration. Hospitals administer PAP more frequently than outpatient settings, with most surveyed institutions following facility-specific internal standards for antibiotic administration. The number of arthroscopies performed in the surveyed centres does not influence antibiotic administration. CONCLUSIONS: The use of PAP in wrist arthroscopies in Germany is inconsistent. The increased use in arthroscopies with bone involvement corresponds to AWMF guidelines, but a general recommendation for wrist arthroscopies, including soft tissue arthroscopies, is necessary to provide physicians with medical and legal certainty.


Asunto(s)
Profilaxis Antibiótica , Artroscopía , Infección de la Herida Quirúrgica , Articulación de la Muñeca , Humanos , Alemania , Articulación de la Muñeca/cirugía , Infección de la Herida Quirúrgica/prevención & control , Procedimientos Quirúrgicos Electivos , Adhesión a Directriz , Antibacterianos/uso terapéutico , Antibacterianos/administración & dosificación , Cefalosporinas/uso terapéutico , Cefalosporinas/administración & dosificación
6.
Heliyon ; 10(1): e23681, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38187218

RESUMEN

Keloid scars and Dupuytren's disease are two common, chronic, and incurable fibroproliferative disorders that, among other shared clinical features, may induce joint contractures. We employed bulk RNA sequencing to discern potential shared gene expression patterns and underlying pathological pathways between these two conditions. Our aim was to uncover potential molecular targets that could pave the way for novel therapeutic strategies. Differentially expressed genes (DEGs) were functionally annotated using Gene Ontology (GO) terms and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways with the Database for Annotation, Visualization, and Integrated Discovery (DAVID). The protein-protein-interaction (PPI) networks were constructed by using the Search Tool for the Retrieval of Interacting Genes (STRING) and Cytoscape. The Molecular Complex Detection (MCODE) plugin was used for downstream analysis of the PPI networks. A total of 1922 DEGs were identified within Dupuytren's and keloid samples, yet no overlapping gene expression profiles were detected. Significantly enriched GO terms were related to skin development and tendon formation in keloid scars and Dupuytren's disease, respectively. The PPI network analysis revealed 10 genes and the module analysis provided six protein networks, which might play an integral part in disease development. These genes, including CDH1, ERBB2, CASP3 and RPS27A, may serve as new targets for future research to develop biomarkers and/or therapeutic agents.

7.
J Clin Med ; 13(8)2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38673553

RESUMEN

Background: Elective soft-tissue-only wrist arthroscopy is a standard procedure in hand surgery for the diagnosis and treatment of wrist pain. A number of pathologies can be treated arthroscopically, with the aim of pain reduction and improved wrist mobility. A postinterventional evaluation of the treatment using objective and patient-reported outcome measures (PROMs) allows for an evidence-based statement about the benefits of soft-tissue-only wrist arthroscopy. Methods: A dual-center study combining retro- and prospective clinical analyses of patient outcomes after soft-tissue-only wrist arthroscopies was performed. The data were collected at two hospitals with departments specializing in hand surgery. The outcome was measured by assessing the range of motion of the wrist and its manual strength, as well as PROMs, including Disabilities of the Arm, Shoulder and Hand (DASH) scores. Results: A total of 154 soft interventions met the study criteria and could be included. Seven months after the elective soft-tissue-only wrist arthroscopies, mobility improved significantly for active extension and flexion, as well as the ulnar and radial abduction of the wrist. The grip strength also improved significantly, by an average of 6 kg, during this period. The DASH score improved significantly, from 35 points to 14 points. Additionally, wrist pain at rest was reduced significantly. Conclusions: After elective soft-tissue-only wrist arthroscopy, patients showed an overall functional improvement in their wrist, with a significant reduction in pain and improvement of mobility and grip strength. This study emphasizes the importance of wrist arthroscopy as a successful treatment option for soft tissue pathologies of the wrist.

8.
J Mater Sci Mater Med ; 24(9): 2223-34, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23712537

RESUMEN

Cell-based regenerative therapies for bone defects usually employ bone precursor cells seeded on solid scaffolds. Thermosensitive hydrogels that harden at body core temperature are promising alternative cell carriers as they are applicable minimally invasively. We modified Pluronic® P123 with different chain extenders and assessed rheology and biocompatibility of the resulting hydrogels. The best candidate was tested in a rat's femoral defect model. All gels hardened above 25 °C with butane-diisocyanate-hydrogels (BDI-gels) displaying the highest storage moduli. BDI-gels showed the most favourable biocompatibility and did not affect cellular adipogenic or osteogenic differentiation in vitro. Implantation of BDI-hydrogel into femoral defects did not impede bone healing in vivo as evidenced by µCT and histological analysis. We conclude that thermosensitive BDI-gels are promising alternative cell carriers. The gels harden upon injection in vivo without interfering with bone metabolism. Further experiments will assess the gels' capacity to effectively transport living cells into bone defects.


Asunto(s)
Temperatura Corporal , Hidrogeles/química , Poloxámero/química , Animales , Materiales Biocompatibles , Técnicas In Vitro , Ratas , Reología
9.
Handchir Mikrochir Plast Chir ; 55(5): 350-357, 2023 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-37500070

RESUMEN

Within the last 50 years, there has been a change in trend in flexor tendon surgery. After the introduction of the 2-strand technique, the 4-strand technique was propagated in the 1990s. In order to obtain a status quo of which technique is used in Germany and if the gold standard of the 4-strand suture has changed in favour of a 6-strand suture, we conducted an online survey among members of the DGH ("Deutsche Gesellschaft für Handchirurgie", German Society for Hand Surgery) on the suture technique of flexor tendon injuries zone 2. MATERIAL AND METHODS: An online survey was conducted and sent out by email to all DGH members. The questionnaire included 7 questions. Participants accessed the survey via a link. RESULTS: 155 hand surgeons from Germany participated in the survey. All of them answered the questionnaire in full and all questionnaires were included in the evaluation. The main question of how many strands are currently used for core suturing was answered as follows: 21% (n=32) of the 155 participants (TN) stated that they use a 2-strand suture, 53% used (n=82) a 4-strand suture and 10% used a 6-strand suture. Regarding techniques, 81 TN used the Kirchmayr-Kessler technique or a modification of it, 9 TN used the M-Tang technique, and 15 TN indicated "other technique". The question about the application of an epitendinous suture was overwhelmingly answered with "yes". Here, 98.2% agreed. Only with regard to the suture material, different opinions were found. 68% (n=106) use an absorbable monofilament suture (such as PDS). Just under a quarter (23%, n=36) use a non-absorbable monofilament suture (such as Prolene). CONCLUSION: Flexor tendon surgery has changed considerably due to intensive advances in research during the last decades. It was interesting to note in our survey that German hand surgeons have adapted their suture technique within the last years based on the results of the literature. Our results clearly show that convincing scientific data has an influence on the choice of surgical technique and that discussions about new techniques, e. g. in the context of annual meetings, may well stimulate the auditorium to rethink.


Asunto(s)
Procedimientos de Cirugía Plástica , Traumatismos de los Tendones , Humanos , Tendones/cirugía , Traumatismos de los Tendones/cirugía , Encuestas y Cuestionarios , Técnicas de Sutura , Suturas , Fenómenos Biomecánicos , Resistencia a la Tracción
10.
Burns ; 49(7): 1525-1533, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37821280

RESUMEN

Depending on extent and depth, burn injuries and resulting scars may be challenging and expensive to treat and above all heavily impact the patients' lives. This systematic review represents the current state of knowledge on molecular pathways activated during burn wound healing. All currently known molecular information about gene expression and molecular interactions in mammals has been summarized. An ample interaction of regenerative cytokines, growth factors, ECM-regenerative molecules and proinflammatory immune response became apparent. We identified three molecules to be most often involved in the pathways: TGFB1, ACTA1 and COL1A1. Yet, other factors including FLII, AKT1 and miR-145 were shown to play pivotal roles in burn wound healing as well. This systematic review helps to explain the fundamental molecular proceedings participating in burn wound healing. A number of new molecular interactions and functional connections were identified yielding intriguing new research targets. An interactive version of the first network about molecular pathways and interactions during burn wound healing is provided in the online edition and on WikiPathways.


Asunto(s)
Quemaduras , MicroARNs , Animales , Humanos , Quemaduras/terapia , Cicatrización de Heridas/fisiología , Cicatriz , Mamíferos , MicroARNs/genética
11.
PLoS One ; 18(3): e0283388, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36961845

RESUMEN

Hand and forearm injuries are the most frequent reason for consultations in German emergency departments. Therefore, full recovery has a high social and economic relevance. In this study, data on surgically treated hand injuries in a regional German trauma centre between 01.01.2019 and 31.01.2021 were collected using the new German HandTraumaRegister of the German Society for Hand Surgery. These data were retrospectively analysed and correlated with mobility data of the Bavarian population, the 7-day incidence of Covid-19 infections in Germany and the number of elective hand surgeries. We found that a fall from standing height with consecutive distal radius fracture was the most common injury in women, whereas mechanism of injury and diagnosis were more diverse in men. The populations' mobility correlated well with the number of accidents, which in turn was reciprocal to the 7-day-incidence of Covid-19 infections. The number of elective hand surgeries expectedly dropped significantly during the state-imposed lockdowns. Knowing that mainly young men and elderly women suffer from hand injuries, tailored prevention measures may be elaborated. In order to reduce socioeconomic burden, care for hand injuries and elective hand surgeries must be guaranteed according to the frequency of their occurrence.


Asunto(s)
COVID-19 , Traumatismos de la Mano , Masculino , Humanos , Femenino , Anciano , Centros Traumatológicos , Estudios Retrospectivos , COVID-19/epidemiología , Control de Enfermedades Transmisibles , Traumatismos de la Mano/epidemiología , Traumatismos de la Mano/cirugía
12.
Bone Jt Open ; 4(4): 219-225, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37051839

RESUMEN

Wrist arthroscopy is a standard procedure in hand surgery for diagnosis and treatment of wrist injuries. Even though not generally recommended for similar procedures, general administration of perioperative antibiotic prophylaxis (PAP) is still widely used in wrist arthroscopy. A clinical ambispective dual-centre study was performed to determine whether PAP reduces postoperative infection rates after soft tissue-only wrist arthroscopies. Retrospective and prospective data was collected at two hospitals with departments specialized in hand surgery. During the study period, 464 wrist arthroscopies were performed, of these 178 soft-tissue-only interventions met the study criteria and were included. Signs of postoperative infection and possible adverse drug effects (ADEs) of PAP were monitored. Additionally, risk factors for surgical site infection (SSIs), such as diabetes mellitus and BMI, were obtained. The overall infection rate of SSI was zero. Neither in the PAP group (n = 69) nor in the control group (n = 109) were signs of postoperative infection observed. Observed symptoms of ADEs were three-times higher in the PAP group when compared to the control-group (16.3 vs 5.5%; p = 0.043). No major ADEs were observed, but one in ten patients in the PAP group reported mild to severe intestinal or hypersensitivity symptoms. We demonstrate that the number needed to treat (NNT) with PAP to prevent one postoperative infection in soft-tissue arthroscopies of the wrist is > 109. Conversely, symptoms of ADEs were reported by one out of ten patients given PAP. Considering the high NNT to prevent postoperative infection and the large number of ADEs caused by PAP, we recommend not to use PAP routinely in soft-tissue arthroscopies of the wrist. Subsequent large-scale studies should be conducted to substantiate these results.

13.
Neural Regen Res ; 18(3): 652-656, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36018190

RESUMEN

Recent results emphasize the supportive effects of adipose-derived multipotent stem/progenitor cells (ADSPCs) in peripheral nerve recovery. Cultivation under hypoxia is considered to enhance the release of the regenerative potential of ADSPCs. This study aimed to examine whether peripheral nerve regeneration in a rat model of autologous sciatic nerve graft benefits from an additional custom-made fibrin conduit seeded with hypoxic pre-conditioned (2% oxygen for 72 hours) autologous ADSPCs (n = 9). This treatment mode was compared with three others: fibrin conduit seeded with ADSPCs cultivated under normoxic conditions (n = 9); non-cell-carrying conduit (n = 9); and nerve autograft only (n = 9). A 16-week follow-up included functional testing (sciatic functional index and static sciatic index) as well as postmortem muscle mass analyses and morphometric nerve evaluations (histology, g-ratio, axon density, and diameter). At 8 weeks, the hypoxic pre-conditioned group achieved significantly higher sciatic functional index/static sciatic index scores than the other three groups, indicating faster functional regeneration. Furthermore, histologic evaluation showed significantly increased axon outgrowth/branching, axon density, remyelination, and a reduced relative connective tissue area. Hypoxic pre-conditioned ADSPCs seeded in fibrin conduits are a promising adjunct to current nerve autografts. Further studies are needed to understand the underlying cellular mechanism and to investigate a potential application in clinical practice.

14.
Eur J Dermatol ; 33(6): 604-611, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38465540

RESUMEN

Wound healing and skin regeneration after injury are complex biological processes, and deep injuries with a high degree of tissue destruction may result in severe scar formation. Clinically, scars can be classified into normal, hypertrophic and keloid scars. However, the molecular signature of each scar type is currently not known. The aim of this study was to reveal the transcriptional landscape of normal, hypertrophic and keloid skin scars following hand and plastic surgery based on total RNA sequencing. Eighteen skin scar samples from hand and plastic surgeries of human donors were minced directly after removal and stored in TRIzol (Thermo Fisher, USA). Samples were then subjected to RNA isolation, cDNA library preparation, bulk RNA sequencing and bioinformatics analysis. We show that keloid scars transcriptionally differed from normal and hypertrophic scars. Normal and hypertrophic scars presented overlapping clustering, and eight genes were shown to be commonly expressed between hypertrophic and normal scars. No genes were specifically expressed at a higher level in keloid and normal scars. Based on gene ontology pathway analysis, genes with a higher level of expression in keloid scars lead to increased (extra-) cellular matrix proliferation and cell interaction. Moreover, tumour-like genes were more highly expressed in keloid scars, supporting the clinical impression of strong and diffuse growth. This study furthers our understanding of the classification of differential scar types based on molecular signature, which may shed light on new diagnostic and therapeutic strategies for keloid scars in the future.


Asunto(s)
Cicatriz Hipertrófica , Queloide , Humanos , Queloide/genética , Queloide/patología , Cicatriz Hipertrófica/genética , Cicatriz Hipertrófica/metabolismo , Cicatriz Hipertrófica/patología , Piel/patología , Cicatrización de Heridas/genética , Hipertrofia/patología
15.
Biochem Biophys Res Commun ; 423(2): 379-85, 2012 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-22664105

RESUMEN

Human mesenchymal stem cells (hMSCs) are regularly cultured and characterised under normoxic (21% O(2)) conditions, although the physiological oxygen tension in the stem cell niche is known to be as low as 1-2%. Oxygen itself is an important signalling molecule, but the distinct impact on various stem cell characteristics is still unclear. Therefore, the aim of this study was to evaluate the influence of oxygen concentration on the hMSC subpopulation composition, cell morphology and migration on different surfaces (polystyrene, collagen I, fibronectin, laminin) as well as on the expression of integrin receptors. Bone marrow-derived hMSCs were cultured either in normoxic (21% O(2)) or hypoxic (2% O(2)) conditions. The hMSC subpopulations were assessed by aspect ratio and cell area. Hypoxia promoted a more homogeneous cell population with a significantly higher fraction of rapidly self-renewing cells which are believed to be the true stem cells. Under hypoxic conditions hMSC volume and height were significantly decreased on all surfaces as measured by white light confocal microscopy. Furthermore, low oxygen tension led to a significant increase in cell velocity and Euclidian distance on all matrixes, which was evaluated by time-lapse microscopy. With regard to cell-matrix contacts, expression of several integrin subunits was evaluated by semi-quantitative RT-PCR. Increased expression of the subunits α(1), α(3), α(5,) α(6), α(11), α(v), ß(1) and ß(3) was observed in hypoxic conditions, while α(2) was higher expressed in normoxic cultured hMSCs. Taken together, our results indicate that hypoxic conditions promote stemness and migration of hMSC along with altering their integrin expression.


Asunto(s)
Movimiento Celular , Integrinas/biosíntesis , Células Madre Mesenquimatosas/fisiología , Oxígeno/fisiología , Adulto , Técnicas de Cultivo de Célula , Hipoxia de la Célula , Tamaño de la Célula , Células Cultivadas , Humanos , Masculino , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/efectos de los fármacos , Oxígeno/farmacología
16.
J Mater Sci Mater Med ; 23(11): 2793-801, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22843167

RESUMEN

Tissue engineering is an attractive approach to heal bony defects. However, three-dimensional cell-scaffold constructs display uneven oxygen supply resulting in inhomogeneous tissue quality. We assessed different strategies to improve oxygen supply in vitro. Scaffolds with differing inner surface were seeded with preosteoblastic cells and cultivated either statically or in perfusion bioreactors. Oxygen concentration and pH were measured in the center of the scaffolds. An inductive feedback mechanism was build to increase bioreactor pump speed according to the oxygen concentrations measured within the scaffolds. While pH remained stable, oxygen concentration decreased significantly under static conditions within the cell-seeded scaffolds. Reducing the scaffolds' inner surface as well as increasing perfusion speeds in bioreactors resulted in improved oxygen supply. We conclude that improving oxygen supply to three dimensional culture systems for bone tissue engineering is feasible in an automated manner. Culture conditions have to be adapted to each cell-scaffold system individually.


Asunto(s)
Automatización , Huesos/citología , Hipoxia de la Célula , Oxígeno/metabolismo , Ingeniería de Tejidos , Células 3T3 , Animales , Reactores Biológicos , Técnicas de Cultivo de Célula , Concentración de Iones de Hidrógeno , Ratones , Andamios del Tejido
17.
J Oral Maxillofac Surg ; 68(5): 1158-61, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20138420

RESUMEN

Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is a side effect of bisphosphonate therapy, primarily diagnosed in patients with cancer and metastatic bone disease and receiving intravenous administrations of nitrogen-containing bisphosphonates. If diagnosis or treatment is delayed, BRONJ can develop to a severe and devastating disease. Numerous studies have focused on BRONJ, with possible pathomechanisms identified to be oversuppression of bone turnover, ischemia due to antiangiogenetic effects, local infections, or soft tissue toxicity. However, the precise pathogenesis largely remains elusive and questions of paramount importance await to be answered, namely 1) Why is only the jaw bone affected? 2) Why and how do the derivatives differ in their potency to induce a BRONJ? and 3) Why and when is BRONJ manifested? The present perspective reflects on existing theories and introduces the hypothesis that local tissue acidosis in the jaw bone offers a conclusive pathogenesis model and may prove to be the missing link in BRONJ.


Asunto(s)
Conservadores de la Densidad Ósea/efectos adversos , Difosfonatos/efectos adversos , Enfermedades Maxilomandibulares/inducido químicamente , Osteonecrosis/inducido químicamente , Acidosis/complicaciones , Conservadores de la Densidad Ósea/clasificación , Resorción Ósea/fisiopatología , Difosfonatos/clasificación , Humanos , Concentración de Iones de Hidrógeno , Maxilares/efectos de los fármacos , Factores de Riesgo
18.
Plast Reconstr Surg ; 145(1): 151-159, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31592943

RESUMEN

BACKGROUND: This study aims to present a new therapeutic option for the treatment of thumb carpometacarpal joint osteoarthritis. Knowing that autologous fat may be beneficial for osteoarthritis through antiinflammatory and chondroprotective effects, the authors transplanted autologous adipose fat into the thumb carpometacarpal joint with the objective of postponing definite resection arthroplasty surgery. METHODS: In this pilot study, the authors performed surgery on 99 joints. The study population consisted of patients with symptomatic and radiologically confirmed osteoarthritis of the thumb carpometacarpal joint. After harvesting abdominal adipose tissue, 1 to 2 ml of fat without physical or enzymatic manipulation were transplanted into the thumb carpometacarpal joint. Surgical outcome was quantified by use of the Michigan Hand Outcomes Questionnaire in addition to strength and pain measurements during a 12-month follow-up consultation. We conducted Friedman's analysis of variance to gauge the differences over time regarding Michigan Hand Outcomes Questionnaire and pain under stress. RESULTS: From 2 weeks on, there was pain relief, both under stress and at rest. Friedman's analysis of variance revealed a significant change in pain under stress [chi-square (5) = 68.52; p < 0.001]. Postoperative Michigan Hand Outcomes Questionnaire Scores improved significantly over 12 months [chi-square (5) = 90.56; p < 0.001]. CONCLUSION: The authors' preliminary findings suggest that intraarticular autologous fat transplantation is a promising alternative treatment of carpometacarpal joint osteoarthritis of the thumb. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.


Asunto(s)
Tejido Adiposo/trasplante , Artroplastia/métodos , Articulaciones Carpometacarpianas/cirugía , Osteoartritis/cirugía , Pulgar/cirugía , Adulto , Anciano , Femenino , Fuerza de la Mano , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Satisfacción del Paciente , Proyectos Piloto , Rango del Movimiento Articular , Adulto Joven
19.
J Plast Reconstr Aesthet Surg ; 73(1): 166-175, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31451404

RESUMEN

BACKGROUND: Adipose-derived stem/progenitor cells (ADSPCs) are under investigation in many clinical applications for their regenerative potential in a variety of autoimmune, degenerative, and inflammatory diseases. Adipose tissue, which is mainly harvested by manual liposuction, is the main source of these ADSPCs. OBJECTIVE: In the past years, a variety of different liposuction devices have been commercialized. To ensure a high quality of obtained ADSPCs, it is crucial to show the advantages and disadvantages of frequently used liposuction methods. For this reason, the objective of this study was to compare ADSPCs harvested by either the suction-assisted LipiVage200-5 or the water-assisted Body-Jet system. METHODS: The proliferation potential of ADSPCs, harvested from 20 patients, was assessed by cumulative population doublings (cumPD), population doubling time (PDT), colony-forming units (CFU), and cell metabolism assays. To prove the multipotency of the primary isolated cells, ADSPCs were induced to differentiate into adipogenic, osteogenic, and chondrogenic lineages. RESULTS: Our data show a significantly higher cumPD, as well as a significantly lower PDT for cells obtained by the Body-Jet system. No significant differences were found regarding the CFU efficiency and the cell metabolism. Furthermore, we showed that the adipogenic, osteogenic, and chondrogenic potential of ADSPCs is similar in both groups. DISCUSSION/CONCLUSION: In our study, we provide evidence that the cell characteristics and the functional properties of ADSPCs isolated after liposuction with different techniques are largely similar. However, we observed a significantly higher cumPD and a slightly higher adipogenic potential in cells isolated after liposuction with the Body-Jet system. Different cannula sizes and sheer stresses in the used methods might play a role here.


Asunto(s)
Tejido Adiposo/trasplante , Lipectomía/métodos , Trasplante de Células Madre/instrumentación , Adipocitos/citología , Adipocitos/trasplante , Tejido Adiposo/citología , Adulto , Anciano , Proliferación Celular , Femenino , Humanos , Lipectomía/instrumentación , Masculino , Persona de Mediana Edad , Células Madre/citología , Donantes de Tejidos , Recolección de Tejidos y Órganos/instrumentación , Agua
20.
J Mater Sci Mater Med ; 20(10): 2001-9, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19466531

RESUMEN

Although gluing bone is in theory a very attractive alternative to classical fracture treatment, this method is not yet clinically established due to the lack of an adhesive which would meet all the necessary requirements. We therefore developed a novel two-component bioadhesive system with the potential to be used as a bone adhesive based on biocompatible and degradable biopolymers (chitosan, oxidised dextran or starch). After mixing in water, the two components covalently cross-link by forming a Schiff's base. By the same mechanism, the glue binds to any other exposed amino group such as for example those exposed in fractured bone, even in the presence of water. Modified chitosan was synthesised from commercially available chitosan by deacetylation and was then reduced in molecular weight by heating in acid. The amount of free amino groups was analysed by IR. The molecular weight was determined by viscosimetry. Starch or dextran were oxidised with periodic acid to generate aldehyde groups, which were quantified by titration. l-Dopa was conjugated to oxidised dextran or starch in analogy to the gluing mechanism of mussels. Biomechanical studies revealed that the new glue is superior to fibrin glue, but has less adhesive strength than cyanoacrylates. In vitro cell testing demonstrated excellent biocompatibility, rendering this glue a potential candidate for clinical use.


Asunto(s)
Cementos para Huesos/química , Polisacáridos/química , Adhesivos Tisulares/química , Implantes Absorbibles , Adhesividad , Animales , Cementos para Huesos/síntesis química , Cementos para Huesos/farmacología , Adhesión Celular , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Quitosano/química , Quitosano/farmacología , Fibroblastos/efectos de los fármacos , Ensayo de Materiales , Ratones , Peso Molecular , Polisacáridos/farmacología , Adhesivos Tisulares/síntesis química , Adhesivos Tisulares/farmacología , Pruebas de Toxicidad
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