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91.
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Background

Although osteochondral lesions of the knee are frequently associated with patellar dislocation and ligament injuries, there are no evidence-based strategies for therapy. Without treatment they can lead to osteoarthritis; therefore, the aim is to restore a durable and resilient cartilage. This article presents an in-house treatment algorithm.

Therapy

There is general agreement that detached cartilage fragments should be refixed early, if suitable. Small fragments less than 1 cm in size can be removed and a defect in the load-bearing zone should be treated with bone marrow stimulation techniques. Major fragments should be refixed. For this purpose bioresorbable implants are available, which now have a similar stability and biocompatibility to metallic implants with the advantages of reducing corresponding cartilage lesions and avoiding removal. Even major pure chondral fragments have the potential for healing and should be refixed as the first line treatment, especially in younger patients. If a fragment is not amenable for refixation or in cases of treatment failure, cartilage restorative and reparative procedures, such as microfracturing, osteochondral transfer or chondrocyte transplantation are used depending on the size, location and bone involvement.

Conclusion

Osteochondral refixation shows good clinical results and should be primarily pursued whenever possible.
  相似文献   
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95.
Alveolar rhabdomyosarcoma (ARMS) is associated with chromosomal translocations that generate PAX3-FKHR and PAX7-FKHR fusion oncoproteins. Based on studies demonstrating that high PAX3-FKHR expression causes growth suppression, the hypothesis is proposed that, during ARMS tumorigenesis, the translocations cause low oncoprotein expression and are followed by collaborating events that block growth suppression pathways and permit upregulation of oncoprotein expression. To investigate oncogenic function at low expression levels, PAX3-FKHR was introduced into NIH3T3 cells in the pBabe retroviral vector. Compared to high expression systems, PAX3-FKHR expression from pBabe was lower and did not suppress growth, but showed transforming activity in the soft agar assay. As a possible collaborating event, PAX3-FKHR paired box mutations were previously shown in high expression systems to reverse growth suppressive effects. In the low expression system, the paired box mutation enhanced transformation in soft agar and focus formation assays. Although these mutations are candidate collaborating events, sequencing of paired box regions in ARMS tumors did not identify mutations. Finally, genes from known genetic alterations in ARMS were introduced, alone or combined, into NIH3T3 cells with high PAX3-FKHR expression and did not rescue growth suppression. In summary, these studies provide a model for an event in ARMS tumorigenesis that enhances PAX3-FKHR oncogenicity and abrogates growth suppression, but do not demonstrate a known event occurring in ARMS tumors that fulfills these criteria.  相似文献   
96.
Retroviral integration and human gene therapy   总被引:4,自引:1,他引:3       下载免费PDF全文
Long-term correction of genetic diseases requires permanent integration of therapeutic genes into chromosomes of affected cells. Retroviral vectors are the most widely used delivery vehicles because of their efficiency and precision of integration. However, retroviral integration can take place at a variety of chromosomal sites, and examples have been reported of integration of therapeutic vectors activating oncogenes and causing cancer in patients. This issue of the JCI presents three articles that update successful human gene therapy trials and furthermore evaluate the sites of integration in cells from treated patients, including samples from individuals experiencing serious adverse events following therapy (see the related articles beginning on pages 2225, 2233, and 2241).  相似文献   
97.
The mononuclear phagocyte (MP) system is a body-wide macrophage (MPhi) and dendritic cell (DC) network, which contributes to tissue homeostasis, inflammation, and immune defense. The in vivo origins of MPs remain poorly understood. Here, we use an adoptive precursor cell transfer strategy into MP-depleted mice to establish the in vivo differentiation sequence from a recently identified MPhi/DC-restricted bone marrow (BM) precursor (MDP) via BM and blood intermediates to peripheral MPhis and DCs. We show that MDPs are in vivo precursors of BM and blood monocytes. Interestingly, grafted Gr1high "inflammatory" blood monocytes shuttle back to the BM in the absence of inflammation, convert into Gr1low monocytes, and contribute further to MP generation. The grafted monocytes give rise to DCs in the intestinal lamina propria and lung, but not to conventional CD11chigh DCs in the spleen, which develop during homeostasis from MDPs without a monocytic intermediate.  相似文献   
98.

Background

The four different local therapy strategies used for head and neck rhabdomyosarcoma (HNRMS) include proton therapy (PT), photon therapy (RT), surgery with radiotherapy (Paris-method), and surgery with brachytherapy (AMORE). Local control and survival is comparable; however, the impact of these different treatments on facial deformation is still poorly understood. This study aims to quantify facial deformation and investigates the differences in facial deformation between treatment modalities.

Methods

Across four European and North American institutions, HNRMS survivors treated between 1990 and 2017, more than 2 years post treatment, had a 3D photograph taken. Using dense surface modeling, we computed facial signatures for each survivor to show facial deformation relative to 35 age–sex–ethnicity-matched controls. Additionally, we computed individual facial asymmetry.

Findings

A total of 173 HNRMS survivors were included, survivors showed significantly reduced facial growth (p < .001) compared to healthy controls. Partitioned by tumor site, there was reduced facial growth in survivors with nonparameningeal primaries (p = .002), and parameningeal primaries (p ≤.001), but not for orbital primaries (p = .080) All patients were significantly more asymmetric than healthy controls, independent of treatment modality (p ≤ .001). There was significantly more facial deformation in orbital patients when comparing RT to AMORE (p = .046). In survivors with a parameningeal tumor, there was significantly less facial deformation in PT when compared to RT (p = .009) and Paris-method (p = .007).

Interpretation

When selecting optimal treatment, musculoskeletal facial outcomes are an expected difference between treatment options. These anticipated differences are currently based on clinicians’ bias, expertise, and experience. These data supplement clinician judgment with an objective analysis highlighting the impact of patient age and tumor site between existing treatment options.  相似文献   
99.
Christou  N.  Ris  F.  Naumann  D.  Robert-Yap  J.  Mathonnet  M.  Gillion  J.-F. 《Hernia》2022,26(1):233-242
Hernia - Surgical site infections (SSIs) following groin hernia repair (GHR) are getting rarer in high income countries despite a wider use of meshes. Among the risk factors for SSIs, those related...  相似文献   
100.
Ex vivo lung perfusion (EVLP) with pharmacological reconditioning may increase donor lung utilization for transplantation (LTx). 3‐Aminobenzamide (3‐AB), an inhibitor of poly(ADP‐ribose) polymerase (PARP), reduces ex vivo lung injury in rat lungs damaged by warm ischemia (WI). Here we determined the effects of 3‐AB reconditioning on graft outcome after LTx. Three groups of donor lungs were studied: Control (Ctrl): 1 hour WI + 3 hours cold ischemia (CI) + LTx; EVLP: 1 hour WI + 3 hours EVLP + LTx; EVLP + 3‐AB: 1 hour WI + 3 hours EVLP + 3‐AB (1 mg.mL?1) + LTx. Two hours after LTx, we determined lung graft compliance, edema, histology, neutrophil counts in bronchoalveolar lavage (BAL), mRNA levels of adhesion molecules within the graft, as well as concentrations of interleukin‐6 and 10 (IL‐6, IL‐10) in BAL and plasma. 3‐AB reconditioning during EVLP improved compliance and reduced lung edema, neutrophil infiltration, and the expression of adhesion molecules within the transplanted lungs. 3‐AB also attenuated the IL‐6/IL‐10 ratio in BAL and plasma, supporting an improved balance between pro‐ and anti‐inflammatory mediators. Thus, 3‐AB reconditioning during EVLP of rat lung grafts damaged by WI markedly reduces inflammation, edema, and physiological deterioration after LTx, supporting the use of PARP inhibitors for the rehabilitation of damaged lungs during EVLP.  相似文献   
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