Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 48
Filtrar
1.
Sci Rep ; 13(1): 18613, 2023 10 30.
Artículo en Inglés | MEDLINE | ID: mdl-37903877

RESUMEN

The concept of donor-unrestricted T cells (DURTs) comprises a heterogeneity of lymphoid cells that respond to an abundance of unconventional epitopes in a non-MHC-restricted manner. Vaccinologists strive to harness this so far underexplored branch of the immune system for new vaccines against tuberculosis. A particular division of DURTs are T cells that recognize their cognate lipid antigen in the context of CD1-molecules. Mycobacteria are characterized by a particular lipid-rich cell wall. Several of these lipids have been shown to be presented to T cells via CD1b-molecules. Guinea pigs functionally express CD1b and are hence an appropriate small animal model to study the role of CD1b-restricted, lipid-specific immune responses. In the current study, guinea pigs were vaccinated with BCG or highly-purified, liposome-formulated phosphatidylinositol-hexa-mannoside (PIM6) to assess the effect of CD1-restricted DURTs on the course of infection after virulent Mycobacterium tuberculosis (Mtb) challenge. Robust PIM6-specific T cell-responses were observed both after BCG- and PIM6-vaccination. The cellular response was significantly reduced in the presence of monoclonal, CD1b-blocking antibodies, indicating that a predominant part of this reactivity was CD1b-restricted. When animals were challenged with Mtb, BCG- and PIM6-vaccinated animals showed significantly reduced pathology, smaller necrotic granulomas in lymph node and spleen and reduced bacterial loads. While BCG conferred an almost sterile protection in this setting, compared to control animals' lesions were reduced roughly by two thirds in PIM6-vaccinated. Comprehensive histological and transcriptional analyses in the draining lymph node revealed that protected animals showed reduced transcription-levels of inflammatory cyto- and chemokines and higher levels of CD1b-expression on professional antigen cells compared to controls. Although BCG as a comparator induced by far stronger effects, our observations in the guinea pig model suggest that CD1b-restricted, PIM6-reactive DURTs contribute to immune-mediated containment of virulent Mtb.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis , Cobayas , Animales , Vacuna BCG , Tuberculosis/prevención & control , Vacunación , Fosfatidilinositoles
2.
Z Orthop Unfall ; 161(1): 57-64, 2023 Feb.
Artículo en Inglés, Alemán | MEDLINE | ID: mdl-35189656

RESUMEN

The Working Group of the German Orthopedic and Trauma Society (DGOU) on Tissue Regeneration has published recommendations on the indication of different surgical approaches for treatment of full-thickness cartilage defects in the knee joint in 2004, 2013 and 2016. Based upon new scientific knowledge and new developments, this recommendation is an update based upon the best clinical evidence available. In addition to prospective randomised controlled clinical trials, this also includes studies with a lower level of evidence. In the absence of evidence, the decision is based on a consensus process within the members of the working group.The principle of making decision dependent on defect size has not been changed in the new recommendation either. The indication for arthroscopic microfracturing has been reduced up to a defect size of 2 cm2 maximum, while autologous chondrocyte implantation is the method of choice for larger cartilage defects. Additionally, matrix-augmented bone marrow stimulation (mBMS) has been included in the recommendation for defects ranging from 1 to 4.5 cm2. For the treatment of smaller osteochondral defects, in addition to osteochondral transplantation (OCT), mBMS is also recommended. For larger defects, matrix-augmented autologous chondrocyte implantation (mACI/mACT) in combination with augmentation of the subchondral bone is recommended.


Asunto(s)
Enfermedades de los Cartílagos , Cartílago Articular , Procedimientos Ortopédicos , Ortopedia , Humanos , Estudios Prospectivos , Enfermedades de los Cartílagos/cirugía , Articulación de la Rodilla/cirugía , Condrocitos , Cartílago Articular/cirugía , Cartílago Articular/lesiones
3.
Molecules ; 25(4)2020 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-32079339

RESUMEN

Polymeric particles are ideal drug delivery systems due to their cellular uptake-relevant size. Microparticles could be developed for direct injection of drug formulations into a diseased site, such as a tumor, allowing for drug retention and slow drug exposure over time through sustained release mechanisms. Bombyx mori silk fibroin has shown promise as a biocompatible biomaterial both in research and the clinic. Silk has been previously used to make particles using an emulsion-based method with poly(vinyl alcohol) (PVA). In this study, polydimethylsiloxane-based microfluidic devices were designed, fabricated, and characterized to produce silk particles through self-association of silk when exposed to PVA. Three main variables resulted in differences in particle size and size distribution, or polydispersity index (PDI). Utilizing a co-flow microfluidic device decreased the PDI of the silk particles as compared to an emulsion-based method (0.13 versus 0.65, respectively). With a flow-focusing microfluidics device, lowering the silk flow rate from 0.80 to 0.06 mL/h resulted in a decrease in the median particle size from 6.8 to 3.0 µm and the PDI from 0.12 to 0.05, respectively. Lastly, decreasing the silk concentration from 12% to 2% resulted in a decrease in the median particle size from 5.6 to 2.8 µm and the PDI from 0.81 to 0.25, respectively. Binding and release of doxorubicin, a cytotoxic drug commonly used for cancer treatment, with the fabricated silk particles was evaluated. Doxorubicin loading in the silk particles was approximately 41 µg/mg; sustained doxorubicin release occurred over 23 days. When the cytotoxicity of the released doxorubicin was tested on KELLY neuroblastoma cells, significant cell death was observed. To demonstrate the potential for internalization of the silk particles, both KELLY and THP-1-derived macrophages were exposed to fluorescently labelled silk particles for up to 24 h. With the macrophages, internalization of the silk particles was observed. Additionally, THP-1 derived macrophages exposure to silk particles increased TNF-α secretion. Overall, this microfluidics-based approach for fabricating silk particles utilizing PVA as a means to induce phase separation and silk self-assembly is a promising approach to control particle size and size distribution. These silk particles may be utilized for a variety of biomedical applications including drug delivery to multiple cell types within a tumor microenvironment.


Asunto(s)
Microtecnología/instrumentación , Alcohol Polivinílico/química , Reología/instrumentación , Seda/química , Animales , Bombyx , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Doxorrubicina/química , Humanos , Imagenología Tridimensional , Microfluídica , Peso Molecular , Neuroblastoma/patología , Seda/farmacología , Células THP-1 , Factor de Necrosis Tumoral alfa/metabolismo
4.
Int Orthop ; 43(5): 1107-1112, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30167834

RESUMEN

PURPOSE: To evaluate the factors influencing the baseline Knee Injury and Osteoarthritis Outcome Score (KOOS) in patients with knee cartilage defects and planned cartilage repair surgery and to provide baseline KOOS data from a large patient population. MATERIAL AND METHODS: Between October 2013 and April 2017, a total of 2815 patients assigned for cartilage repair surgery were included into the German Cartilage Registry (KnorpelRegister DGOU) and their data were analyzed for the present study. Multivariate regression model and ANOVA were used to detect patient- and defect-specific factors with an influence on baseline KOOS. In addition, KOOS baseline data was calculated and compared according to these parameters. RESULTS: Sex, age, body mass index (BMI), and smoking status were revealed as patient-specific factors, and defect location and the number of previous knee and cartilage operations were revealed as defect-specific factors with a significant influence on baseline KOOS. Most subscores were affected in accordance with the total KOOS. Interestingly, defect ICRS grade, defect size, and symptom duration had no significant influence. The mean baseline KOOS was 56.7 (± 17.9). Men had significantly higher mean overall KOOS (60 ± 17.3 vs. 51.8 ± 17.6, p < 0.001) than women, and patients with a BMI over 30 and smokers scored significantly lower (58.07 ± 17.67 vs. 50.32 ± 17.29, p < 0.001; 57.64 ± 17.86 vs. 53.59 ± 18.06, p < 0.001). Patients with two or more previous knee operations as well as patients with more than one previous cartilage procedure also showed significantly lower overall KOOS (57.19 ± 17.89 vs. 54.56 ± 17.58, p < 0.001; 57.68 ± 18.01 vs. 52.72 ± 17.58, p < 0.001). CONCLUSION: Several factors influencing baseline KOOS data in patients with knee cartilage defects assigned for cartilage repair surgery could be detected. Their individual influence in the multivariate linear regression model was not very strong. Baseline data according to these criteria is presented in this paper.


Asunto(s)
Enfermedades de los Cartílagos/epidemiología , Enfermedades de los Cartílagos/patología , Cartílago Articular/patología , Articulación de la Rodilla/patología , Sistema de Registros/estadística & datos numéricos , Adulto , Enfermedades de los Cartílagos/cirugía , Cartílago Articular/cirugía , Femenino , Alemania/epidemiología , Indicadores de Salud , Humanos , Articulación de la Rodilla/cirugía , Masculino , Persona de Mediana Edad
5.
Z Orthop Unfall ; 155(6): 670-682, 2017 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-28915523

RESUMEN

Background Symptomatic pre-arthritic deformities such as femoroacetabular impingement (FAI) or hip dysplasia often lead to localised cartilage defects and subsequently to osteoarthritis. The present review of the working group "Clinical Tissue Regeneration" of the German Society of Orthopaedics and Trauma (DGOU) and the hip committee of the AGA (German speaking Society for Arthroscopy and Joint Surgery) provides an overview of current knowledge of the diagnosis and surgical treatment of cartilage defects, in order to infer appropriate therapy recommendations for the hip. Methods Review of FAI and resultant cartilage damage in the hip as reported in published study findings in the literature and discussion of the advantages and disadvantages of different surgical procedures to preserve the joint. Results Most published studies on the surgical treatment of cartilage damage in the hip report defects caused by cam-type FAI at the acetabulum. Development of these defects can be prevented by timely elimination of the relevant deformities. At present, current full-thickness cartilage defects are mostly treated with bone marrow-stimulating techniques such as microfracture (MFx), with or without a biomaterial, and matrix-assisted autologous chondrocyte transplantation (MACT). Osteochondral autologous transplantation (OAT) is not the treatment of choice for isolated full-thickness chondral defects at the hip, because of the unfavourable risk-benefit profile. Due to the relatively short history of cartilage repair surgery on the hip, the studies available on these procedures have low levels of evidence. However, it is already becoming obvious that the experience gained with the same procedures on the knee can be applied to the hip as well. For example, limited healing and regeneration of chondral defects after MFx can also be observed at the hip joint. Conclusions The cartilage surface of the acetabulum, where FAI-related chondral lesions appear, is considerably smaller than the weight-bearing cartilage surface of the knee joint. However, as in the knee joint, MACT is the therapy of choice for full-thickness cartilage defects of more than 1.5 - 2 cm2. Minimally invasive types of MACT (e.g. injectable chondrocyte implants) should be preferred in the hip joint. In cases where a single-stage procedure is indicated or there are other compelling reasons for not performing a MACT, a bone marrow-stimulating technique in combination with a biomaterial covering is preferable to standard MFx. For treatment of lesions smaller than 1.5 - 2 cm2 the indication for a single-stage procedure is wider. As with defects in the knee, it is not possible to determine a definite upper age limit for joint-preserving surgery or MACT in the hip, as the chronological age of patients does not necessarily correlate with their biological age or the condition of their joints. Advanced osteoarthritis of the hip is a contraindication for any kind of hip-preserving surgery. Long-term observations and prospective randomised studies like those carried out for other joints are necessary.


Asunto(s)
Cartílago Articular/cirugía , Condrocitos/trasplante , Pinzamiento Femoroacetabular/cirugía , Luxación de la Cadera/cirugía , Articulación de la Cadera/cirugía , Proteínas Matrilinas/uso terapéutico , Osteoartritis de la Cadera/cirugía , Factores de Edad , Trasplante de Células , Contraindicaciones , Pinzamiento Femoroacetabular/diagnóstico , Regeneración Tisular Dirigida , Luxación de la Cadera/diagnóstico , Humanos , Inyecciones Intraarticulares , Procedimientos Quirúrgicos Mínimamente Invasivos , Osteoartritis de la Cadera/diagnóstico
6.
Z Orthop Unfall ; 155(4): 457-467, 2017 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-28521382

RESUMEN

Purpose This multicenter study was aimed to evaluate the coincidence of degenerative knee cartilage lesions with a varus or valgus dysalignment. Furthermore, the frequency of the combined surgery of cartilage treatments and corrective osteotomies are determined. Material and Methods A total of 1778 patients were included in the German CartilageRegistry (deadline 01.08.2016). In 90.6% of patients, the surgeon calculated the alignment by clinical observation. Varus or valgus conditions were measured radiologically in only 56.0%. This study describes patients who underwent treatment of degenerative cartilage lesions with a complete (clinical and radiological) determination of the alignment. Results The mean mechanical tibia-femur angle (Paley) (mTFA) in clinically neutral extremities was 0.2° (SD 0.6; 0 - 5), in varus cases 5,0° (SD 3.2; 0 - 15), and - 4.7° (SD - 4.0; - 15 - 0) in valgus cases. Varus dysalignment was significantly associated with cartilage lesions in the medial compartment. Valgus dysalignment more frequently occurred in knees with lateral cartilage lesions. Independently of the surgeon's choice of the method of cartilage surgery, in 72.4% of all valgus deformities a corrective osteotomy was performed. Valgus dysalignment was corrected in 50%. Conclusions In about a quarter of all cases, cartilage lesions are associated with a varus (18.9%) or valgus (4.2%) dysalignment. In a number of cases, the treatment of cartilage lesions should include the addressing of these axial deviations. Still the efficacy of this procedure regarding prognosis and clinical outcome is unclear.


Asunto(s)
Desviación Ósea/epidemiología , Osteoartritis de la Rodilla/epidemiología , Sistema de Registros/estadística & datos numéricos , Adolescente , Adulto , Anciano , Desviación Ósea/cirugía , Comorbilidad , Femenino , Genu Valgum/epidemiología , Genu Valgum/cirugía , Genu Varum/epidemiología , Genu Varum/cirugía , Alemania , Humanos , Masculino , Meniscos Tibiales/cirugía , Persona de Mediana Edad , Osteoartritis de la Rodilla/cirugía , Valores de Referencia , Adulto Joven
7.
Microb Cell Fact ; 16(1): 72, 2017 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-28446175

RESUMEN

BACKGROUND: Bacillus pumilus cells exhibit a significantly higher resistance to hydrogen peroxide compared to closely related Bacilli like Bacillus subtilis. RESULTS: In this study we analyzed features of the catalase KatX2 of B. pumilus as one of the most important parts of the cellular response to hydrogen peroxide. KatX2, the vegetative catalase expressed in B. pumilus, was compared to the vegetative catalase KatA of B. subtilis. Data of our study demonstrate that B. pumilus can degrade toxic concentrations of hydrogen peroxide faster than B. subtilis. By replacing B. subtilis katA gene by katX2 we could significantly enhance its resistance to H2O2 and its potential to eliminate this toxic compound. Mutant cells showed a 1.5- to 2-fold higher survival to toxic concentrations of hydrogen peroxide compared to wild type cells. Furthermore, we found reversible but also irreversible oxidations of the KatX2 protein which, in contrast to KatA, contains several cysteine residues. CONCLUSIONS: Our study indicates that the catalase KatX2 plays a major role in the increased resistance of B. pumilus to oxidative stress caused by hydrogen peroxide. Resistance to hydrogen peroxide of other Bacilli can be enhanced by exchanging the native catalase in the cells with katX2.


Asunto(s)
Bacillus pumilus/enzimología , Bacillus subtilis/efectos de los fármacos , Bacillus subtilis/genética , Catalasa/metabolismo , Peróxido de Hidrógeno/farmacología , Bacillus pumilus/genética , Catalasa/química , Catalasa/genética , Farmacorresistencia Bacteriana , Regulación Bacteriana de la Expresión Génica , Peróxido de Hidrógeno/metabolismo , Mutación , Estrés Oxidativo
8.
Toxicol In Vitro ; 40: 45-54, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27998807

RESUMEN

Extracts of Arnica spp. are traditionally used due to their anti-inflammatory effects for the topical treatment of e.g. haematoma or muscle distortions. One of the main active compounds is Helenalin, a sesquiterpene lactone that can be found in various Asteraceae. However, immunotoxic effects of the compound are only poorly analysed. In this study, a 2D gel electrophoresis based proteomic approach together with a membrane based proteomic assay, metabolomics and the detection of intracellular reactive oxygen species (iROS) were used to investigate potential immunotoxic properties of Helenalin on the human immune cell lines Jurkat and THP-1 and on human peripheral blood mononuclear cells (PBMC). The study revealed a dose-dependent cytotoxicity towards both tested cell lines and the PBMC. However, the cell lines were less sensitive to the Helenalin treatment than the PBMC. The proteomic assays showed strong effects on the carbohydrate metabolism and the protein folding in THP-1 cells but only weak impact on Jurkat cells. Metabolomic studies as well as iROS detection in THP-1 cells verified the results of the proteomic analysis. In summary, the approaches used in this study were able to identify target pathways of Helenalin especially in THP-1 monocytes and thus enable a risk assessment of the substance.


Asunto(s)
Antiinflamatorios/farmacología , Sesquiterpenos/farmacología , Apoptosis/efectos de los fármacos , Metabolismo de los Hidratos de Carbono/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Citocinas/metabolismo , Humanos , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/metabolismo , Metaboloma/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Proteoma/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Sesquiterpenos de Guayano
9.
J Biomed Mater Res A ; 105(2): 608-618, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27737520

RESUMEN

Central nervous system (CNS) injuries and diseases result in neuronal damage and loss of function. Transplantation of neural stem cells (NSCs) has been shown to improve locomotor function after transplantation. However, due to the immune and inflammatory response at the injury site, the survival rate of the engrafted cells is low. Engrafted cell viability has been shown to increase when transplanted within a hydrogel. Hyaluronic acid (HA) hydrogels have natural anti-inflammatory properties and the backbone can be modified to introduce bioactive agents, such as anti-Fas, which we have previously shown to promote NSC survival while suppressing immune cell activity in bulk hydrogels in vitro. Although bulk HA hydrogels have shown to promote stem cell survival, microsphere gels for NSC encapsulation and delivery may have additional advantages. In this study, a flow-focusing microfluidic device was used to fabricate either vinyl sulfone-modified HA (VS-HA) or anti-Fas-conjugated HA (anti-Fas HA) microsphere gels encapsulated with NSCs. The majority of encapsulated NSCs remained viable for at least 24 h in the VS-HA and anti-Fas HA microsphere gels. Moreover, T-cells cultured in suspension with the anti-Fas HA microsphere gels had reduced viability after contact with the microsphere gels compared to the media control and soluble anti-Fas conditions. This approach can be adapted to encapsulate various cell types for therapeutic strategies in other physiological systems in order to increase survival by reducing the immune response. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 608-618, 2017.


Asunto(s)
Anticuerpos/química , Ácido Hialurónico/química , Microesferas , Células-Madre Neurales , Receptor fas , Células Cultivadas , Células Inmovilizadas/citología , Células Inmovilizadas/metabolismo , Células Inmovilizadas/trasplante , Geles , Humanos , Proteínas Inmovilizadas/química , Células-Madre Neurales/citología , Células-Madre Neurales/metabolismo , Células-Madre Neurales/trasplante , Linfocitos T/citología , Linfocitos T/metabolismo
10.
Arch Orthop Trauma Surg ; 136(7): 891-7, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27062375

RESUMEN

PURPOSE: Treatment of cartilage defects of the knee remains an important issue with high relevance. In October 2013 the German Cartilage Registry (KnorpelRegister DGOU) was initiated in order to study indications, epidemiology and (clinical) outcome of different cartilage repair techniques. The present evaluation of the registry baseline data was initiated to report common practices of cartilage repair surgery in Germany. MATERIALS AND METHODS: 1065 consecutive patients who underwent surgical cartilage treatment of the knee have been included (complete data sets available in 1027 cases; FU rate 96.4 %) between October 1, 2013 and June 30, 2015. Data collection was performed using a web-based RDE System. All data were provided by the attending physician at the time of arthroscopic or open surgery of the affected knee. RESULTS: In 1027 cartilage repair procedures, single defects were treated in 80 % of the cases with the majority of the defects located on the medial femoral condyle, followed by the patella. Degenerative defects grade III or IV according to ICRS were treated in 60 % of the cases and therefore were found more frequently compared to traumatic or post-traumatic lesions. Autologous chondrocyte implantation (ACI) was the most common technique followed by bone marrow stimulation (BMS) and osteochondral transplantation (OCT). While ACI was performed in defects with a mean size of 4.11 cm(2) SD SD 2.16), BMS and OCT (1.51 cm(2), SD 1.19; p < 0.01) were applied in significantly smaller defects (both p < 0.01). Independent of defect size, the ratio of ACI versus BMS applications differed between different defect locations. ACI was used preferably in defects located on the patella. CONCLUSION: The present analysis of data from the German Cartilage Registry shows that the vast majority of cartilage repair procedures were applied in degenerative, non-traumatic cartilage defects. Experts in Germany seem to follow the national and international guidelines in terms that bone marrow stimulation is applied in smaller cartilage defects while cell-based therapies are used for the treatment of larger cartilage defects. In patellar cartilage defects a trend towards the use of cell-based therapies has been observed.


Asunto(s)
Enfermedades de los Cartílagos/cirugía , Articulación de la Rodilla/cirugía , Procedimientos Ortopédicos/métodos , Adulto , Cartílago/cirugía , Cartílago/trasplante , Condrocitos/trasplante , Femenino , Alemania , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Procedimientos Ortopédicos/estadística & datos numéricos , Sistema de Registros , Trasplante Autólogo/métodos , Trasplante Autólogo/estadística & datos numéricos , Adulto Joven
11.
Arch Orthop Trauma Surg ; 136(6): 805-10, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27001180

RESUMEN

INTRODUCTION: Knee cartilage lesions are very frequent in arthroscopic surgery. This multi-center-study was aimed to evaluate the distribution and possible associated factors of these pathologies in more than 1000 patients. MATERIALS AND METHODS: The German cartilage registry (KnorpelRegister DGOU) started in 2013. In this paper, we present the baseline-data (distribution of knee cartilage lesions and the demographic data) of more than 1000 cases since the registries' start-up. RESULTS: A total number of 47 centers were involved into this multicenter study. A total of 1071 patients primary were registered. Degenerative knees 629 times (61.8 %) and injured knees 302 times (29.6 %) were involved. In the remaining 89 knees (8.7 %) the genesis of cartilage lesions was unclear. Single defects were observed in 792 cases (77.6 %). Most frequently the medial femoral condyle or the patella was affected. In 78 knees (7.6 %) the main-defect was associated with a defect of the corresponding joint surface. In the remaining cases complex cartilage damages were found. CONCLUSIONS: Our results are in confirmation with other multicenter studies. But these former studies did not differentiate into traumatic and degenerative lesions. Furthermore no characteristics were given regarding to single, kissing or complex lesions. Thus this database will be a sufficient instrument for the investigation of the "natural course" of cartilage lesions, but above all about the effectiveness of different treatment options.


Asunto(s)
Cartílago Articular/lesiones , Traumatismos de la Rodilla/epidemiología , Osteoartritis de la Rodilla/epidemiología , Adolescente , Adulto , Anciano , Artroscopía , Cartílago Articular/cirugía , Niño , Femenino , Alemania/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Sistema de Registros , Adulto Joven
12.
Injury ; 46 Suppl 4: S2-9, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26542862

RESUMEN

INTRODUCTION: Since the first description of autologous chondrocyte implantation (ACI) in 1994 different methods and improvements were established for this regenerative treatment option of large chondral defects. This study analyzes safety and short-term clinical results from characterized ACI using a collagen based biphasic scaffold and evaluates prognostic factors. METHODS: 433 patients with a mean age of 33.4 years and localized grade III to IV cartilage defects (ICRS classification) in the knee or ankle were included. Mean defect size was 5.9 cm(2). Prior seeding of the scaffold, expanded chondrocytes were characterized by RT-PCR on 6 different marker genes (type I and II collagen, aggrecan, interleukin-1 ß (IL-1ß), vascular endothelial growth factor receptor 1 (FLT-1) and bone sialoprotein-2 (BSP-2)). Clinical outcome was evaluated using a questionnaire for defect history, basic demographics, time elapsed from surgery, 10-point outcome assessments of pain, function and swelling. Moreover, adverse events (AEs) or subsequent treatments were recorded and analysed. RESULTS: Patients improved significantly over baseline (p < 0.0001) in pain, function and swelling. Subjects with later than 12 months follow-up reported nominally greater mean changes. Graft failure incidence was 6% for patients with greater than one year follow-up. Graft-related complications were significantly higher for patellar (p < 0.0001) and degenerative defects (p = 0.005). Elevated expression of FLT-1 (p = 0.02) or IL-1 ß mRNA (p = 0.03) was associated with graft-related AEs. A borderline association was found for low collagen type II expression (p = 0.08). CONCLUSION: Early graft-related AEs after ACI with a biphasic collagen scaffold are related to defect type, location and marker gene expression. The levels of significance observed for gene expression with respect to graft-related AEs were subordinate to those identified in the analysis of lesion history and location.


Asunto(s)
Traumatismos del Tobillo/terapia , Enfermedades de los Cartílagos/terapia , Trasplante de Células , Condrocitos/trasplante , Traumatismos de la Rodilla/terapia , Adulto , Traumatismos del Tobillo/metabolismo , Traumatismos del Tobillo/fisiopatología , Enfermedades de los Cartílagos/fisiopatología , Cartílago Articular , Colágeno Tipo I/metabolismo , Femenino , Supervivencia de Injerto , Humanos , Interleucina-1beta/metabolismo , Traumatismos de la Rodilla/metabolismo , Traumatismos de la Rodilla/fisiopatología , Masculino , Rango del Movimiento Articular , Recuperación de la Función , Estudios Retrospectivos , Trasplante Autólogo , Factor A de Crecimiento Endotelial Vascular/metabolismo
13.
BMC Microbiol ; 15: 71, 2015 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-25879753

RESUMEN

BACKGROUND: With the aim of remaining viable, bacteria must deal with changes in environmental conditions, including increases in external osmolarity. While studies concerning bacterial response to this stress condition have focused on soil, marine and enteric species, this report is about Caulobacter crescentus, a species inhabiting freshwater oligotrophic habitats. RESULTS: A genomic analysis reported in this study shows that most of the classical genes known to be involved in intracellular solute accumulation under osmotic adaptation are missing in C. crescentus. Consistent with this observation, growth assays revealed a restricted capability of the bacterium to propagate under hyperosmotic stress, and addition of the compatible solute glycine betaine did not improve bacterial resistance. A combination of transcriptomic and proteomic analyses indicated quite similar changes triggered by the presence of either salt or sucrose, including down-regulation of many housekeeping processes and up-regulation of functions related to environmental adaptation. Furthermore, a GC-MS analysis revealed some metabolites at slightly increased levels in stressed cells, but none of them corresponding to well-established compatible solutes. CONCLUSION: Despite a clear response to hyperosmotic stress, it seems that the restricted capability of C. crescentus to tolerate this unfavorable condition is probably a consequence of the inability to accumulate intracellular solutes. This finding is consistent with the ecology of the bacterium, which inhabits aquatic environments with low nutrient concentration.


Asunto(s)
Adaptación Fisiológica/genética , Proteínas Bacterianas/genética , Caulobacter crescentus/genética , Regulación Bacteriana de la Expresión Génica , Proteínas Bacterianas/metabolismo , Betaína/farmacología , Transporte Biológico , Caulobacter crescentus/efectos de los fármacos , Caulobacter crescentus/metabolismo , Agua Dulce/microbiología , Perfilación de la Expresión Génica , Anotación de Secuencia Molecular , Concentración Osmolar , Presión Osmótica , Cloruro de Sodio/farmacología , Estrés Fisiológico , Sacarosa/farmacología
14.
Mol Cell Proteomics ; 13(11): 3063-81, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25056936

RESUMEN

Listeria monocytogenes is a firmicute bacterium causing serious infections in humans upon consumption of contaminated food. Most of its virulence factors are secretory proteins either released to the medium or attached to the bacterial surface. L. monocytogenes encodes at least six different protein secretion pathways. Although great efforts have been made in the past to predict secretory proteins and their secretion routes using bioinformatics, experimental evidence is lacking for most secretion systems. Therefore, we constructed mutants in the main housekeeping protein secretion systems, which are the Sec-dependent transport, the YidC membrane insertases SpoIIIJ and YqjG, as well as the twin-arginine pathway, and analyzed their secretion and virulence defects. Our results demonstrate that Sec-dependent secretion and membrane insertion of proteins via YidC proteins are essential for viability of L. monocytogenes. Depletion of SecA or YidC activity severely affected protein secretion, whereas loss of the Tat-pathway was without any effect on secretion, viability, and virulence. Two-dimensional gel electrophoresis combined with protein identification by mass spectrometry revealed that secretion of many virulence factors and of enzymes synthesizing and degrading the cell wall depends on the SecA route. This finding was confirmed by SecA inhibition experiments using sodium azide. Analysis of secretion of substrates typically dependent on the accessory SecA2 ATPase in wild type and azide resistant mutants of L. monocytogenes revealed for the first time that SecA2-dependent protein secretion also requires the ATPase activity of the house-keeping SecA protein.


Asunto(s)
Adenosina Trifosfatasas/genética , Proteínas Bacterianas/genética , Sistemas de Secreción Bacterianos/genética , Listeria monocytogenes/patogenicidad , Proteínas de Transporte de Membrana/genética , Adenosina Trifosfatasas/metabolismo , Animales , Arginina/metabolismo , Proteínas Bacterianas/metabolismo , Línea Celular Tumoral , Perfilación de la Expresión Génica , Células HeLa , Humanos , Listeria monocytogenes/genética , Listeria monocytogenes/metabolismo , Ratones , Proteómica , Canales de Translocación SEC , Proteína SecA , Factores de Virulencia/genética
15.
Infect Immun ; 82(9): 3599-611, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24914223

RESUMEN

Candidate small RNAs (sRNAs) have recently been identified in Enterococcus faecalis, a Gram-positive opportunistic pathogen, and six of these candidate sRNAs with unknown functions were selected for a functional study. Deletion mutants and complemented strains were constructed, and their virulence was tested. We were unable to obtain the ef0869-0870 mutant, likely due to an essential role, and the ef0820-0821 sRNA seemed not to be involved in virulence. In contrast, the mutant lacking ef0408-0409 sRNA, homologous to the RNAII component of the toxin-antitoxin system, appeared more virulent and more able to colonize mouse organs. The three other mutants showed reduced virulence. In addition, we checked the responses of these mutant strains to several stresses encountered in the gastrointestinal tract or during the infection process. In parallel, the activities of the sRNA promoters were measured using transcriptional fusion constructions. To attempt to identify the regulons of these candidate sRNAs, proteomics profiles of the mutant strains were compared with that of the wild type. This showed that the selected sRNAs controlled the expression of proteins involved in diverse cellular processes and the stress response. The combined data highlight the roles of certain candidate sRNAs in the adaptation of E. faecalis to environmental changes and in the complex transition process from a commensal to a pathogen.


Asunto(s)
Enterococcus faecalis/genética , Estrés Fisiológico/genética , Virulencia/genética , Animales , Femenino , Tracto Gastrointestinal/microbiología , Regulación Bacteriana de la Expresión Génica/genética , Infecciones por Bacterias Grampositivas/genética , Infecciones por Bacterias Grampositivas/microbiología , Macrófagos/microbiología , Ratones , Ratones Endogámicos BALB C , Mutación/genética , Regiones Promotoras Genéticas/genética , ARN Bacteriano/genética
16.
BMC Res Notes ; 7: 201, 2014 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-24684773

RESUMEN

BACKGROUND: With incorrect or even without treatment, acute injuries of the posterior cruciate ligament (PCL) can lead to chronic instability of the knee joint. After delayed treatment, negative occupational changes and reduced quality of life can occur. These aspects have not yet been investigated. The purpose of this study was to evaluate occupational consequences after isolated reconstruction in cases of chronic PCL insufficiency. FINDINGS: 12 patients treated with PCL reconstruction in a single bundle technique, using hamstring tendon grafts, were evaluated. All patients were operated upon at least 3 months after injury. Mean time of follow-up was 51 ± 18.2 months (14-75). Radiological assessment (Telos stress device) showed a side comparison of total translation of 4.5 ± 2.6 mm. Occupational consequences have been evaluated by the classification system "REFA". Median time incapacity for work was 8 weeks. Nearly all patients achieved the mental status of the normal population (SF-36), but physical status was still restricted. A pre- to postoperative improvement of the clinical scores could be seen: Lysholm-Score: 46.4 ± 17.3 to 84.7 ± 14.1, HSS-Score: 74.3 ± 10.5 to 88.3 ± 10.7. Postoperative evaluated scores were: Tegner score: 4.8 ± 1.2, IKDC score: 80.0 ± 16.2, VPS: 3.4 ± 2.7. Patients with low physical load in their workplace described significantly better clinical results in every clinical score (p < .05) and less pain than patients with high physical load prior to the accident (VPS: REFA < 2: 2.4 ± 2.6, REFA ≥ 2: 5.5 ± 1.7; p < 0.05). CONCLUSIONS: Operative treated patients with a chronic PCL insufficiency achieve an improvement of the clinical result. Patients with low physical load at their workplace achieve less restrictions.


Asunto(s)
Procedimientos de Cirugía Plástica , Ligamento Cruzado Posterior/cirugía , Recuperación de la Función/fisiología , Adolescente , Adulto , Femenino , Estudios de Seguimiento , Humanos , Inestabilidad de la Articulación/fisiopatología , Masculino , Ligamento Cruzado Posterior/lesiones , Tendones/trasplante , Factores de Tiempo , Trasplante Autólogo , Índices de Gravedad del Trauma , Resultado del Tratamiento , Soporte de Peso
17.
PLoS One ; 8(11): e80956, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24348917

RESUMEN

The Gram-positive endospore-forming bacterium Bacillus licheniformis can be found widely in nature and it is exploited in industrial processes for the manufacturing of antibiotics, specialty chemicals, and enzymes. Both in its varied natural habitats and in industrial settings, B. licheniformis cells will be exposed to increases in the external osmolarity, conditions that trigger water efflux, impair turgor, cause the cessation of growth, and negatively affect the productivity of cell factories in biotechnological processes. We have taken here both systems-wide and targeted physiological approaches to unravel the core of the osmostress responses of B. licheniformis. Cells were suddenly subjected to an osmotic upshift of considerable magnitude (with 1 M NaCl), and their transcriptional profile was then recorded in a time-resolved fashion on a genome-wide scale. A bioinformatics cluster analysis was used to group the osmotically up-regulated genes into categories that are functionally associated with the synthesis and import of osmostress-relieving compounds (compatible solutes), the SigB-controlled general stress response, and genes whose functional annotation suggests that salt stress triggers secondary oxidative stress responses in B. licheniformis. The data set focusing on the transcriptional profile of B. licheniformis was enriched by proteomics aimed at identifying those proteins that were accumulated by the cells through increased biosynthesis in response to osmotic stress. Furthermore, these global approaches were augmented by a set of experiments that addressed the synthesis of the compatible solutes proline and glycine betaine and assessed the growth-enhancing effects of various osmoprotectants. Combined, our data provide a blueprint of the cellular adjustment processes of B. licheniformis to both sudden and sustained osmotic stress.


Asunto(s)
Bacillus/metabolismo , Bacillus/efectos de los fármacos , Betaína/farmacología , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Presión Osmótica/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos
18.
Reprod Biol ; 13(3): 184-94, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24011189

RESUMEN

Recently we showed that essential components for the initiation of protein synthesis, namely the eukaryotic initiation factor 4E (eIF4E, mRNA-cap-binding protein) and its repressors 4E-BP1 as well as 4E-BP2, are proteolytically processed in the porcine endometrium during implantation. Here, the situation during placentation was compared with ovariectomized (OVX) animals and animals on pregnancy day 1 (PD1). Furthermore, the research was extended to factors which phosphorylate eIF4E and 4E-BPs and regulate their activities. These are the protein kinase B/mammalian target of rapamycin kinase (Akt/mTor) with the regulators Raptor and Rictor as well as the mitogen activated protein kinases (MAPKs): extra cellular-signal regulated kinase 1 and 2 (ERK1 and ERK2). Striking differences in the placentation site (PS) and the areas aside from PS (peri-PS) were observed. EIF4E and 4E-BP2 truncation as well as 4E-BP1 degradation took place in the endometrium of the peri-PS on PD24. Accompanied by a fragmentation of Akt/mTor, no expression of Rictor was observed, whereas the abundance of Raptor was not altered. On the contrary, MAPKs expression and phosphorylation remained almost stable in the peri-PS. In conclusion, the results indicated that on PD24 the translational regulation was shifted to 4E-BP2 control. Furthermore, the Akt/mTor signaling cascade seemed to be down regulated which suggest reduced phosphorylation of 4E-BP2. Whereas Akt was proteolyzed, the observed mTor fragments represented most likely splicing variants. The results indicate that translational control of gene expression is an important feature in the porcine endometrium during early pregnancy.


Asunto(s)
Factor 4E Eucariótico de Iniciación/fisiología , Proteínas Proto-Oncogénicas c-akt/fisiología , Transducción de Señal/fisiología , Serina-Treonina Quinasas TOR/fisiología , Útero/metabolismo , Animales , Implantación del Embrión/fisiología , Femenino , Fosforilación , Placentación , Embarazo , Porcinos
19.
Cell ; 154(5): 1023-1035, 2013 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-23972393

RESUMEN

Foraging animals have distinct exploration and exploitation behaviors that are organized into discrete behavioral states. Here, we characterize a neuromodulatory circuit that generates long-lasting roaming and dwelling states in Caenorhabditis elegans. We find that two opposing neuromodulators, serotonin and the neuropeptide pigment dispersing factor (PDF), each initiate and extend one behavioral state. Serotonin promotes dwelling states through the MOD-1 serotonin-gated chloride channel. The spontaneous activity of serotonergic neurons correlates with dwelling behavior, and optogenetic modulation of the critical MOD-1-expressing targets induces prolonged dwelling states. PDF promotes roaming states through a Gαs-coupled PDF receptor; optogenetic activation of cAMP production in PDF receptor-expressing cells induces prolonged roaming states. The neurons that produce and respond to each neuromodulator form a distributed circuit orthogonal to the classical wiring diagram, with several essential neurons that express each molecule. The slow temporal dynamics of this neuromodulatory circuit supplement fast motor circuits to organize long-lasting behavioral states.


Asunto(s)
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/fisiología , Neuropéptidos/metabolismo , Serotonina/metabolismo , Transducción de Señal , Animales , Conducta Animal , Canales de Cloruro/metabolismo , AMP Cíclico/metabolismo , Neuronas/metabolismo , Receptores Acoplados a Proteínas G/metabolismo
20.
Int J Food Microbiol ; 165(1): 35-42, 2013 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-23685728

RESUMEN

Listeria monocytogenes is a food-borne pathogen known to persist in food production environments, where it is able to attach and form biofilms, potentially contaminating food products ready for consumption. In this study the first step in the establishment of L. monocytogenes in a food-processing environment was examined, namely the initial adhesion to stainless steel under specific dynamic flow conditions. It was found that the intrinsic ability of L. monocytogenes to adhere to solid surfaces under flow conditions is dependent on nutrient availability. The addition of L-leucine to the growth medium altered the fatty acid composition of the L. monocytogenes cells and increased adhesion. The growth conditions resulting in the highest adhesion (growth medium with added glucose) had cells with the highest electron donating and lowest electron accepting properties, whereas growth conditions resulting in lowest adhesion (growth medium with added mannose) had cells with the lowest electron donating properties and highest electron accepting properties. The highest and lowest adhesion conditions correlated with differences in expression of cell surface protein of L. monocytogenes and among these the autolysin amidase (Ami). This study implies that food composition influences the adhesion of L. monocytogenes to solid surfaces during dynamic flow conditions.


Asunto(s)
Adhesión Bacteriana , Listeria monocytogenes/fisiología , Acero Inoxidable , Adhesión Bacteriana/efectos de los fármacos , Biopelículas , Medios de Cultivo/farmacología , Ácidos Grasos/análisis , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Leucina/farmacología , Listeria monocytogenes/química , Listeria monocytogenes/efectos de los fármacos , Listeria monocytogenes/crecimiento & desarrollo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA