A case report on escitalopram-induced hyperglycaemia in a diabetic patient

The incidence of depression in diabetic patients is quite high; moreover, it has been suggested that the presence of depression itself may increase the risk of diabetes mellitus. Hence, it follows that the simultaneous use of antidiabetic and antidepressant drugs is common. Some clinical evidence indicates that selective serotonin re-uptake inhibitors (SSRIs) could be very useful in treating overweight patients, both with and without diabetes. However, recent deregulation of glucidic metabolism was tested in diabetic subjects treated with antidepressants. Several cases of hyperglycaemia and hypoglycaemia associated with other SSRIs have been published, whereas only one case of escitalopram inducing hyperglycaemia has been noted. The exact mechanism of glucose control impairment in patients taking SSRIs--escitalopram in particular--still remains unclear. We describe a diabetic 83-year-old woman with good glycaemic control (as evinced by glycaemic and glycosylated haemoglobin assay--HbA1c--values) before escitalopram initiation in response to therapy with glibenclamide. Escitalopram resulted in a significantly increased glycaemia values 5 days following administration. Glycaemia values returned to normality only after suspension of escitalopram, despite antidiabetic dosage increase. We report this case to draw attention to escitalopram as a possible cause of glycaemic control loss.

GALAMOST: GPU-accelerated large-scale molecular simulation toolkit

GALAMOST [graphics processing unit (GPU)-accelerated large-scale molecular simulation toolkit] is a molecular simulation package designed to utilize the computational power of GPUs. Besides the common features of molecular dynamics (MD) packages, it is developed specially for the studies of self-assembly, phase transition, and other properties of polymeric systems at mesoscopic scale by using some lately developed simulation techniques. To accelerate the simulations, GALAMOST contains a hybrid particle-field MD technique where particle–particle interactions are replaced by interactions of particles with density fields. Moreover, the numerical potential obtained by bottom-up coarse-graining methods can be implemented in simulations with GALAMOST. By combining these force fields and particle-density coupling method in GALAMOST, the simulations for polymers can be performed with very large system sizes over long simulation time. In addition, GALAMOST encompasses two specific models, that is, a soft anisotropic particle model and a chain-growth polymerization model, by which the hierarchical self-assembly of soft anisotropic particles and the problems related to polymerization can be studied, respectively. The optimized algorithms implemented on the GPU, package characteristics, and benchmarks of GALAMOST are reported in detail.

Abstract P3-15-04: A French prospective pilot study to identify dihydropyrimidine dehydrogenase (DPD) deficiency in breast cancer patients receiving capecitabine

Background: Health Authorities point out that DPD deficiency confers a significant risk of major toxicity for patients receiving capecitabine. Identification of at-risk patients is thus of major concern. This multicentric prospective study of the French GPCO group (Groupe de Pharmacologie Clinique Oncologique, Unicancer) evaluated the sensitivity, specificity and predictive values of DPD phenotyping and genotyping to predict severe cap-related toxixity in metastatic breast cancer patients.

Methods: 303 patients were included between February 2009 and February 2011 (15 institutions). Eighty-eight% received capecitabine as monotherapy, 28% were treated as first line (mean dose at 1st cycle 1957 mg/m2/d). Pre-treatment uracil (U, physiological DPD substrate) plasma concentration was measured in 286 patients (HPLC assay). DPD genotyping (IVS14+1G>A, 2846A>T, 1679T>G, 464T>A) was performed on 281 patients. Severe toxicity (G3-4 CTCAE v3 criteria) was measured over cycles 1-2.

Results: Grade 3-4 toxicity (diarrhea, vomiting, hematoxicity, hand-foot syndrome) has been observed in 19.6% of patients (one toxic death). A marked trend for higher U concentrations has been noted in patients developing severe toxicity vs those who didn't (median 12.7 ng/ml (Q1-Q3 9-17) vs median 10.2 ng/ml (range 8-13), respectively, p = 0.014). However, ROC curve has showed that this difference was too small for use as a reliable toxicity predictor. The patient with toxic death had an elevated U concentration at 17 ng/ml. Among the 7 patients with a DPD mutation (3 pts IVS14+1, 3 pts 2846A>T, one 1679T>G, all heterozygous), 5 developed severe toxicity (including the toxic death, 2846A>T), one did not, and the last one was not documented. Relative risk for developing severe toxicity was 4.60 in mutated patients vs wild-type patients (95%CI 2.95-7.16, p = 0.001); positive and negative predictive values were 83.3% and 81.9%, respectively; specificity was 99.5% and sensitivity was 9.8%.

Conclusions: Breast cancer patients harbouring a DPD variant allele are at risk to develop severe, up to lethal, capecitabine-related toxicity. Pre-treatment U measurement remains to be more firmly established as a reliable predictor of capecitabine toxicity. These observations are of major interest for breast cancer patients candidate for capecitabine therapy.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-15-04.

Efficacy of marrow-stimulating technique in arthroscopic rotator cuff repair: a prospective randomized study

PURPOSE

To evaluate the efficacy of a marrow-stimulating technique with microfractures of the greater tuberosity during arthroscopic rotator cuff repair.

METHODS

Eighty patients with a full-thickness rotator cuff tear underwent an arthroscopic single-row repair. Patients were divided into 2 groups of 40 cases each. In group 1, standard repair was performed; in group 2, microfractures of the greater tuberosity were performed to enhance tendon repair. Clinical outcome was assessed with the Disabilities of the Arm, Shoulder and Hand (DASH) score and normalized Constant score. Tendon integrity was assessed with magnetic resonance imaging. Multivariate analysis was performed to determine which predictors were independently associated with the outcome. Significance was set at P < .05.

RESULTS

The mean follow-up was 28.1 ± 3 months. Seven patients were lost to follow-up (2 in group 1 and 5 in group 2). Comparison between groups did not show significant differences for baseline characteristics. The mean DASH score was 28.6 ± 21.3 points in group 1 and 23.3 ± 20.1 points in group 2. Although the difference was not statistically significant, the confidence interval included a 10-point value (minimal clinically important difference) in favor of the microfracture group. The difference in the Constant score between groups was not significant. The tendon healing rate was 52.6% in group 1 and 65.7% in group 2, without a significant difference between groups. Subgroup analysis for tear size showed that group 2 had a significantly greater healing rate than group 1 for large tears (P = .040). Multivariate analysis showed that age, timing of symptoms, tear location, tendon retraction, and fatty infiltration significantly affected the outcomes.

CONCLUSIONS

Postoperative magnetic resonance imaging did not show any significant difference between groups in structural integrity. However, subgroup analysis showed a significantly greater healing rate in the microfracture group for large tears involving the supraspinatus and infraspinatus.

LEVEL OF EVIDENCE

Level I, high-quality randomized controlled trial with no statistically significant difference but narrow confidence intervals.

Phase I trial of gemcitabine combined with capecitabine and erlotinib in advanced pancreatic cancer: a clinical and pharmacological study

BACKGROUND

The aim of this phase I trial was to define the maximum tolerated dose (MTD), the dose-limiting toxicity (DLT) and the recommended dose of erlotinib combined with capecitabine and gemcitabine in the treatment of advanced pancreatic cancer (APC).

METHODS

Gemcitabine was administered intravenously at 1,000 mg/m(2)/week (days 1, 8 and 15) and oral capecitabine from day 1 to day 21 at 1,660 mg/m(2)/day. Oral erlotinib was administered daily continuously at escalating doses (28-day cycle). Dose levels (DLs) 1, 2, 3 and 4 were 50, 75, 100 and 125 mg/day, respectively. Pharmacokinetic analysis of the three drugs was performed in the first cycle.

RESULTS

Nineteen patients were enrolled. At the MTD (DL4; 125 mg/day erlotinib), 100% of patients developed DLT consisting of grade 4 febrile neutropenia and nonhematological grade 3 events (vomiting, diarrhea, stomatitis, rash). The most common toxicities, regardless of grade, were neutropenia, anemia, rash and diarrhea. Erlotinib systemic exposure was significantly related to the administered dose. Of note, toxicity was significantly associated with elevated systemic exposure of capecitabine anabolites.

CONCLUSION

When combined concurrently with 1,000 mg/m(2)/week gemcitabine and 1,660 mg/m(2)/day capecitabine, erlotinib can be administered safely at a daily dose of 100 mg in APC patients.

Deep heating therapy via microwave diathermy relieves pain and improves physical function in patients with knee osteoarthritis: a double-blind randomized clinical trial

BACKGROUND

Deep heating therapy (DHT) has shown to improve pain and function in patients with knee osteoarthritis (OA) in the short term. Benefits of superficial heating therapy (SHT) are controversial. Long-term effects of both heating modalities have not yet been investigated.

AIM

To compare the effects of DHT and SHT in patients with symptomatic knee OA, and to determine the long-term effects of heat therapy.

DESIGN

Double-blind randomized clinical trial.

SETTING

Outpatient clinic of Geriatrics and Physiatrics, University Hospital.

POPULATION

Fifty-four patients with radiologically established diagnosis of moderate knee OA (Kellgren-Lawrence grade II or III) and pain lasting for at least three weeks.

METHODS

DHT: local microwave diathermy (three 30-min sessions a week for four weeks); SHT: application of hot packs (three 30-min sessions a week for four weeks).

PRIMARY OUTCOME MEASURE

Western Ontario and McMaster Universities (WOMAC) index for the assessment of joint pain, stiffness and physical function limitations.

SECONDARY OUTCOME MEASURES

British Medical Research Council (BMRC) rating scale for the evaluation of muscle strength, and a visual analogue scale (VAS) for pain assessment. Follow up: 24 weeks for all outcome measures; 12 months for the primary outcome.

RESULTS

Intention-to-treat analyses showed a treatment effect in favor of DHT for all outcome measures. No clinically relevant changes were observed in the SHT group. Benefits of DHT were maintained over 12 months of follow-up.

CONCLUSIONS

DHT via localized microwave diathermy improves pain, muscle strength and physical function in patients affected by knee OA, with benefits maintained over the long term. No clinically relevant improvements were observed in patients who underwent SHT.

CLINICAL REHABILITATION IMPACT

DHT via microwave diathermy delivered three times a week for four weeks significantly improves pain and function in patients affected by moderate knee OA, with benefits retained for at least 12 months. No clinically relevant changes are observed in knee OA patients treated with SHT.

Understanding the interaction of block copolymers with DMPC lipid bilayer using coarse-grained molecular dynamics simulations

In this paper, we present a computational model of the adsorption and percolation mechanism of poloxamers (poly(ethylene oxide) (PEO) and poly(propylene oxide) (PPO) triblock copolymers) across a 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) lipid bilayer. A coarse-grained model was used to cope with the long time scale of the percolation process. The simulations have provided details of the interaction mechanism of Pluronics with lipid bilayer. In particular, the results have shown that polymer chains containing a PPO block with a length comparable to the DMPC bilayer thickness, such as P85, tends to percolate across the lipid bilayer. On the contrary, Pluronics with a shorter PPO chain, such as L64 and F38, insert partially into the membrane with the PPO block part while the PEO blocks remain in water on one side of the lipid bilayer. The percolation of the polymers into the lipid tail groups reduces the membrane thickness and increases the area per lipid. These effects are more evident for P85 than L64 or F38. Our findings are qualitatively in good agreement with published small-angle X-ray scattering experiments that have evidenced a thinning effect of Pluronics on the lipid bilayer as well as the role of the length of the PPO block on the permeation process of the polymer through the lipid bilayer. Our theoretical results complement the experimental data with a detailed structural and dynamic model of poloxamers at the interface and inside the lipid bilayer.

Hybrid particle-field molecular dynamics simulations: parallelization and benchmarks

The parallel implementation of a recently developed hybrid scheme for molecular dynamics (MD) simulations (Milano and Kawakatsu, J Chem Phys 2009, 130, 214106) where self-consistent field theory (SCF) and particle models are combined is described. Because of the peculiar formulation of the hybrid method, considering single particles interacting with density fields, the most computationally expensive part of the hybrid particle-field MD simulation can be efficiently parallelized using a straightforward particle decomposition algorithm. Benchmarks of simulations, including comparisons of serial MD and MD-SCF program profiles, serial MD-SCF and parallel MD-SCF program profiles, and parallel benchmarks compared with efficient MD program GROMACS 4.5.4 are tested and reported. The results of benchmarks indicate that the proposed parallelization scheme is very efficient and opens the way to molecular simulations of large scale systems with reasonable computational costs.

A phase I study of UFT-oral vinorelbine in metastatic breast cancer

BACKGROUND

Despite current treatment options, metastatic breast cancer (MBC) remains essentially incurable, requiring research on new drugs or combinations to improve survival and quality of life.

PATIENTS AND METHODS

This phase I study was designed to define the maximum-tolerated dose (MTD), dose-limiting toxicity (DLT) and recommended dose of all-oral tegafur-uracil (UFT)/folinic acid combined with vinorelbine as chemotherapy for MBC. Starting doses were 40 mg/m(2)/week of oral vinorelbine administered continuously and 250 mg/m(2)/day of UFT plus 90 mg/day of folinic acid from day 1 to day 28, followed by a 1-week rest period.

RESULTS

Ten patients were included. Eight were evaluable for toxicity and antitumor response. The second dose level was shown to be the MTD. At this dose, 2 out of 5 patients receiving oral vinorelbine at 40 mg/m(2)/week and UFT at 300 mg/m(2)/day developed DLT consisting of grade 3 asthenia and grade 3 nausea despite standard prophylaxis. Other toxicities were grade 1 diarrhea and anemia. There were no treatment-related deaths.

CONCLUSIONS

The recommended dose for this combination seems to be the first dose level. A stable response was observed for 6 patients (average 33 weeks). This combination appears to be well-tolerated and offers an alternative to intravenous chemotherapy.

Analysis of risk factors for glenoid bone defect in anterior shoulder instability

BACKGROUND

Glenoid bone defect is frequently associated with anterior shoulder instability and is considered one of the major causes of recurrence of instability after shoulder stabilization.

HYPOTHESIS

Some risk factors are significantly associated with the presence, size, and type of glenoid bone defect.

STUDY DESIGN

Cohort study (prognosis); Level of evidence, 2.

METHODS

One hundred sixty-one patients affected by anterior shoulder instability underwent morphologic evaluation of the glenoid by computed tomography scans to assess the presence, size, and type of glenoid bone defect (erosion or bony Bankart lesion). Bone loss greater than 20% of the area of the inferior glenoid was considered "critical" bone defect (at risk of recurrence). Outcomes were correlated with the following predictors: age, gender, arm dominance, frequency of dislocation, age at first dislocation, timing from first dislocation, number of dislocations, cause of first dislocation, generalized ligamentous laxity, type of sport, and manual work.

RESULTS

Glenoid bone defect was observed in 72% of the cases. Presence of the defect was significantly associated with recurrence of dislocation compared with a single episode of dislocation, increasing number of dislocations, male gender, and type of sport. Size of the defect was significantly associated with recurrent dislocation, increasing number of dislocations, timing from first dislocation, and manual work. Presence of a critical defect was significantly associated with number of dislocations and age at first dislocation. Bony Bankart lesion was significantly associated with male gender and age at first dislocation.

CONCLUSION

The number of dislocations and age at first dislocation are the most significant predictors of glenoid bone loss in anterior shoulder instability.

Development of a coarse-grained model for simulations of tridecanoin liquid-solid phase transitions

Novel coarse-grained models for molecular dynamics of tridecanoin melts are here proposed as results of a coarse-graining step procedure. The procedure is implemented to develop three coarse-grained models of increasing number of particle types from two to four. Force fields are computed by minimization of the deviations of appropriate distribution functions of the coarse-grained models from those of a reference atomistic one. Density, diffusivity and shear viscosity are computed by numerical simulation and compared with experimental values. The ability of each model to describe liquid-solid transitions is also analyzed. In particular, the model with four types of coarse-grained beads shows a transition from a liquid to a crystal phase.

Comparison between 2D and 3D computed tomography evaluation of glenoid bone defect in unilateral anterior gleno-humeral instability

PURPOSE

This study evaluated the agreement between 2D and 3D computed tomography (CT) measurements in identifying the size and type of glenoid-bone defect in anterior glenohumeral instability.

MATERIALS AND METHODS

One hundred patients affected by unilateral anterior glenohumeral instability underwent a CT of both shoulders. Images were processed with both 2D [multiplanar reconstruction (MPR)] and 3D [volumerendering (VR)] methods. The area of the missing glenoid was calculated in comparison with the healthy glenoid and expressed as a percentage. Agreement between the two measurements was assessed according to the Bland-Altman method; a 5% mean difference was considered as clinically relevant.

RESULTS

Analysis of agreement between MPR and VR measurements of the percentage of missing glenoid showed a mean difference equal to 0.62%±1.96%. Percent agreement between the two measurements in detecting the presence of bone defect was 97% (p<0.0001). Percent agreement between the two measurements in discriminating the type of bone defect was 97% (p<0.0001).

CONCLUSIONS

Agreement between 2D (MPR) and 3D (VR) CT measurements to identify the size and type of glenoid-bone defect in anterior glenohumeral instability was so high that the two measurements can be considered interchangeable.

PNA-based artificial nucleases as antisense and anti-miRNA oligonucleotide agents

Because of its interesting chemical, physical and biological properties, Peptide Nucleic Acid (PNA) has attracted major attention in molecular biology, for diagnostics purposes and development of biosensors. PNAs have become candidates for gene therapeutic drugs in ANTISENSE (AO) strategy with favorable in vivo biochemical properties. Recently, antisense PNA oligonucleotides have been described in anti-miRNA approach (AMO). We propose PNA-based nucleases as AO and AMO agents. We report the design, synthesis and characterization of two kinds of artificial nucleases composed of a PEG-PNA-PEG domain conjugated to HGG·Cu (A) and DETA (B) as well known cleavage sites. Qualitative (MALDI-TOF) and quantitative (HTS) assays were planned to study nuclease activity of constructs A and B on RNA-3'-FAM target sequence. The results have highlighted the best performance of nuclease B and the relevance of the PEG spacer, in particular for conjugate A, in terms of efficiency of the cleavage, suggesting that conjugates A and B also act as potential antisense and anti-miRNA agents.

Pressure calculation in hybrid particle-field simulations

In the framework of a recently developed scheme for a hybrid particle-field simulation techniques where self-consistent field (SCF) theory and particle models (molecular dynamics) are combined [J. Chem. Phys. 130, 214106 (2009)], we developed a general formulation for the calculation of instantaneous pressure and stress tensor. The expressions have been derived from statistical mechanical definition of the pressure starting from the expression for the free energy functional in the SCF theory. An implementation of the derived formulation suitable for hybrid particle-field molecular dynamics-self-consistent field simulations is described. A series of test simulations on model systems are reported comparing the calculated pressure with those obtained from standard molecular dynamics simulations based on pair potentials.

The Effect of Autologous Conditioned Plasma on the Treatment of Focal Chondral Defects of the Knee. An Experimental Study

The purpose of the present study was to evaluate the effect of local application of Autologous Conditioned Plasma (ACP) on the treatment of full-thickness cartilage injuries of the knee. The hypothesis of the study was that ACP can enhance healing response of injured cartilage. A full-thickness chondral lesion on the weight-bearing area of the medial femoral condyle was performed in 30 sheep. Animals were divided into 2 groups, according to postoperative treatment: in group 1, weekly injections of ACP for five times were performed; in group 2, lesions were left untreated. Animals were sacrificed at 3, 6 and 12 months after treatment. A histological evaluation was performed according to a modified O'Driscoll histological score. Comparison between groups for each time interval was performed with the Student's t-test. Significance was set at P <0.05. A post-hoc power analysis was performed according to the hypothesis of the study. Histological evaluation at 3 and 6 months showed that group 1 had significantly greater total score than group 2. At 12 months, no significant difference was observed between groups. In conclusion, local injections of ACP for treatment of full-thickness cartilage injuries did not produce hyaline cartilage. However, it promoted reparative response of the cartilage defect until 6 months after treatment.

Comparison between metal and biodegradable suture anchors in the arthroscopic treatment of traumatic anterior shoulder instability: a prospective randomized study

PURPOSE

The purpose of this study was to compare the clinical outcome of arthroscopic treatment of shoulder instability with metal and biodegradable suture anchors.

METHODS

Arthroscopic stabilization was performed in 78 patients with recurrent traumatic anterior shoulder instability. They were divided into 2 groups of 39 patients each, according to suture anchors used: metal anchors in group 1, and biodegradable anchors in group 2. Results were evaluated by use of the Disabilities of the Arm, Shoulder and Hand (DASH) self-administered questionnaire; Rowe score; Constant score normalized for age and gender, and recurrence of dislocation.

RESULTS

On analyzing the results at a 2-year follow-up, we considered the following independent variables: age; gender; arm dominance; duration of symptoms, age at first dislocation, number of dislocations, type of work; type of sport; sports activity level; lesion of the anterior labrum and anterior-inferior gleno-humeral ligament; SLAP lesion, and number of suture anchors. Comparison between groups did not show significant differences for each variable considered. Overall, according to the results, median DASH scores were 4.5 points (range 0-27) in group 1 and 7 points (range 0-25) in group 2 (n.s.); median Rowe scores were 100 points (range 60-100) and 100 points (range 25-100), respectively (n.s.); and median Constant scores were 98 points (range 81-107) and 98 points (range 87-121), respectively (n.s.). Recurrence was observed in 1 patient (2.8%) in group 1 and in 2 patients (5.9%) in group 2. Overall recurrence rate was 4.3%. Univariate and multivariate analysis showed that age, duration of symptoms, number of dislocations, type of work, and type of sports significantly and independently influenced the outcomes. Differences between groups 1 and 2 were not significant.

CONCLUSION

At a short-term follow-up, differences between arthroscopic shoulder stabilization with metal and biodegradable suture anchors were not statistically significant. Clinical relevance of the study is that there is no difference in the use of metal or biodegradable suture anchors for the arthroscopic treatment of shoulder instability.

Arthroscopic rotator cuff repair with metal and biodegradable suture anchors: a prospective randomized study

PURPOSE

The purpose of this study was to compare the clinical outcome of arthroscopic rotator cuff repair with metal and biodegradable suture anchors.

METHODS

Arthroscopic rotator cuff repair was performed in 110 patients with a full-thickness rotator cuff tear. They were divided into 2 groups of 55 patients each, according to suture anchors used: metal anchors in group 1 and biodegradable anchors in group 2. Results were evaluated by use of the Disabilities of the Arm, Shoulder and Hand (DASH) and Work-DASH self-administered questionnaires, as well as the Constant score normalized for age and sex. On analyzing the results at 2 years' follow-up, we considered the following independent variables: baseline scores; age; sex; arm dominance; location, shape, and retraction of cuff tear; fatty degeneration; treatment of biceps tendon; rotator cuff repair technique (anchors or anchors and side to side); and number of anchors. Univariate and multivariate statistical analyses were performed to determine which variables were independently associated with the outcome. Significance was set at P < .05.

RESULTS

Of the patients, 9 (8.2%) were lost to follow-up. Comparison between groups did not show significant differences for each variable considered. Overall, according to the results, the mean DASH scores were 17.6 +/- 17.2 points in group 1 and 22.8 +/- 19.9 points in group 2; the mean Work-DASH scores were 24.9 +/- 28.1 points and 22.5 +/- 24.1 points, respectively; and the mean Constant scores were 104 +/- 20.5 points and 98.6 +/- 14.3 points, respectively. Differences between groups 1 and 2 were not significant. Univariate and multivariate analysis showed that only baseline score, age, tear location, and fatty degeneration significantly and independently influenced the outcome.

CONCLUSIONS

At a short-term follow-up, differences between arthroscopic repair of full-thickness rotator cuff tears with metal and biodegradable suture anchors were not significant.

LEVEL OF EVIDENCE

Level I, high-quality randomized controlled trial with no statistically significant differences but narrow confidence intervals.

Erlotinib in combination with capecitabine (5'dFUR) in resistant pancreatic cancer cell lines

The combination of capecitabine and the tyrosine kinase inhibitor erlotinib has recently been tested in patients with gemcitabine-refractory pancreatic tumors, with limited success. To understand this lack of efficacy, we studied the molecular effects of these agents in Capan-1 and Capan-2 human pancreatic resistant cancer cells. Erlotinib up-regulated thymidine phosphorylase (+50%) and downregulated dihydropyrimidine dehydrogenase (+55%) in a cell-dependent manner, thus suggesting that the combination should result in synergism. However, only mild additivity was achieved at best when combining both drugs, and several sequences tested even led to strong antagonism. Further experiments were performed to understand this lack of efficacy. We found that the fluoropyrimidine down-regulated EGFR expression by 30%, an unexpected finding resulting in a possible reduction in efficacy when cells were subsequently exposed to erlotinib. We also observed marked drug-induced over-expression of both cytosolic and extracellular vascular endothelial growth factor (VEGF) secretion, thus possibly triggering proliferation. These preliminary findings strongly suggest that these observations could be new mechanisms in the development of acquired drug resistance in pancreatic cancer cells.

The effect of platelet rich plasma combined with microfractures on the treatment of chondral defects: an experimental study in a sheep model

OBJECTIVE

To evaluate the effect of autologous platelet rich plasma (PRP) combined with microfractures on the treatment of chondral defects. The hypothesis of the study was that PRP can enhance cartilage repair after microfractures.

METHODS

A chronic full-thickness chondral lesion of the medial femoral condyle was performed in 15 sheep. Animals were divided into three groups, according to treatment: group 1: microfractures; group 2: microfractures+PRP and fibrin glue gel; group 3: microfractures+liquid-PRP injection. Animals were sacrificed at 6 months after treatment. Macroscopic appearance was evaluated according to International Cartilage Repair Society (ICRS) score; cartilage stiffness was analyzed with an electromechanical indenter (Artscan 200); histological appearance was scored according to a modified O'Driscoll score. Comparison between groups for each outcome was performed with Kruskal-Wallis test, and Tukey's test for pairwise comparisons.

RESULTS

Macroscopic ICRS score of group 2 was significantly better than those of the other groups, and score of group 1 was significantly lower than those of the other groups. Scores of group 1 and 3 were significantly lower than that of normal cartilage. Mean cartilage stiffness of groups 1 and 3 was significantly lower than that of normal cartilage. Histological total scores of group 2 and 3 were significantly better than that of group 1.

CONCLUSIONS

PRP showed a positive effect on cartilage repair and restoration after microfractures. The procedure was more effective when PRP was used as a gel in comparison with liquid intra-articular injection. Histological analysis revealed that none of experimental treatments produced hyaline cartilage.