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MYC rearrangements occur in 5% to 10% of diffuse large B-cell lymphomas (DLBCL) and confer an increased risk to cyclophosphamide, hydroxydaunorubicin, oncovin, and prednisone (CHOP) and rituximab (R)-CHOP treated patients. We investigated the prognostic relevance of MYC-, BCL2- and BCL6-rearrangements and protein expression in a prospective randomized trial. Paraffin-embedded tumor samples from 442 de novo DLBCL treated within the RICOVER study of the German High-Grade Non-Hodgkin Lymphoma Study Group (DSHNHL) were investigated using immunohistochemistry and fluorescence in situ hybridization (FISH) to detect protein expression and breaks of MYC, BCL2, and BCL6. Rearrangements of MYC, BCL2, and BCL6 were detected in 8.8%, 13.5%, and 28.7%, respectively. Protein overexpression of MYC (>40%) was encountered in 31.8% of tumors; 79.6% and 82.8% of tumors expressed BCL2 and BCL6, respectively. MYC translocations, MYChigh, BCL2high, and BCL6low protein expressions were associated with inferior survival. In multivariate Cox regression modeling, protein expression patterns of MYC, BCL2 and BCL6, and MYC rearrangements were predictive of outcome and provided prognostic information independent of the International Prognostic Index (IPI) for overall survival and event-free survival. A combined immunohistochemical or FISH/immunohistochemical score predicts outcome in DLBCL patients independent of the IPI and identifies a subset of 15% of patients with dismal prognosis in the high-risk IPI group following treatment with R-CHOP. Registered at http://www.cancer.gov/clinicaltrials: RICOVER trial of the DSHNHL is NCT 00052936.

We report on cascaded frequency conversion at the single-photon level, consisting of a downconversion from the red (738 nm) to a telecom band (1403 nm) and the reverse upconversion process in the same nonlinear crystal. Detecting the converted single photons suffers from a large noise floor. We were able to recover the signal by implementing a lock-in analyzer technique in the data postprocessing.

We demonstrate efficient (>30%) quantum frequency conversion of visible single photons (711 nm) emitted by a quantum dot to a telecom wavelength (1313 nm). Analysis of the first- and second-order coherence before and after wavelength conversion clearly proves that pivotal properties, such as the coherence time and photon antibunching, are fully conserved during the frequency translation process. Our findings underline the great potential of single photon sources on demand in combination with quantum frequency conversion as a promising technique that may pave the way for a number of new applications in quantum technology.

Single silicon vacancy (SiV) color centers in diamond have recently shown the ability for high brightness, narrow bandwidth, room temperature single photon emission. This work develops a model describing the three level population dynamics of single SiV centers in diamond nanocrystals on iridium surfaces including an intensity dependent de-shelving process. Furthermore, we investigate the brightness and photostability of single centers and find maximum single photon rates of 6.2 Mcps under continuous excitation. We investigate the collection efficiency of the fluorescence and estimate quantum efficiencies of the SiV centers.

Diamond is an attractive material for photonic quantum technologies because its colour centres have a number of outstanding properties, including bright single photon emission and long spin coherence times. To take advantage of these properties it is favourable to directly fabricate optical microcavities in high-quality diamond samples. Such microcavities could be used to control the photons emitted by the colour centres or to couple widely separated spins. Here, we present a method for the fabrication of one- and two-dimensional photonic crystal microcavities with quality factors of up to 700 in single crystal diamond. Using a post-processing etching technique, we tune the cavity modes into resonance with the zero phonon line of an ensemble of silicon-vacancy colour centres, and we measure an intensity enhancement factor of 2.8. The controlled coupling of colour centres to photonic crystal microcavities could pave the way to larger-scale photonic quantum devices based on single crystal diamond.

A number of short stems for total hip arthroplasty have been introduced during the last decade. We describe our experience with the NANOS prosthesis (Smith and Nephew, Marl, Germany). The potential increase of bone mass around a femoral short stem using bone densitometry may be an indicator for secondary ingrowth. We report the outcome of 72 NANOS short stems in 65 patients between March 2003 and October 2007. The mean follow-up was 5.2±0.7 years and the mean age of the patients was 63±8.3 years. Along with demographic data and co-morbidities, the Harris Hip Score, the Merle d'Aubigné mobility score, and a patient-centred questionnaire were evaluated pre-operatively and during follow-up. The Mean Harris Hip Score increased from 47.3±12.2 pre-operatively to 97.6±0.6 at the final follow-up. The Merle d'Aubigné mobility score increased from 7.6±1.4 pre-operatively to 11.8±0.3 at the final follow-up. None of the 72 stems were revised, providing a survival rate of 100%. Radiolucent lines were visible rasiographically in two patients during follow-up. The NANOS short stem demonstrated a satisfactory outcome at mid term follow-up. The clinical and radiological results support to the principle of metaphyseal anchorage of a short stem prosthesis. Long term evaluation will be of interest to determine if these encouraging trends are reflected by prolonged survivorship.

Introduction: The purpose of this study was to evaluate the results of a contoured focal articular femoral condyle resurfacing prosthetic in the treatment of full-thickness cartilage and osteochondral defects at the medial femoral condyle of the knee beyond 5 years., Methods: In a multicenter case series, preoperative and follow-up scores of the Knee Injury and Osteoarthritis Outcome Score (KOOS), SF-36 and Tegner activity scale were evaluated. Standard radiographs were performed to evaluate the progression of osteoarthritis. Patients were also asked to report their satisfaction., Results: A total of 21 patients were included in this study. The average follow-up was 5.3 years. The average age at the time of resurfacing was 54 years. Average KOOS scores significantly (P ≤ 0.005) improved for pain (51.1 to 77.6), symptoms (57.9 to 79.5), activities of daily living (ADL) (58.8 to 82.4), sports (26.3 to 57.8) and quality of life (QOL) (34.4 to 55.0). The Tegner activity level improved significantly (P ≤ 0.02) from 2.9 to 4. The physical health value of the SF-36 increased by 15.2 to 46.9 compared to the preoperative value. The mental health value almost (51.2) remained unchanged. As many as 16/21 of the patients in this series were satisfied with their outcome and would have the operation again. Radiographic results demonstrated solid fixation, preservation of joint space and no change in the osteoarthritic stage., Conclusions: The device appears to be an effective reconstructive treatment option for large full-thickness cartilage and osteochondral lesions of the knee in middle-aged patients.

We report on single photon frequency downconversion from the red part of the spectrum (738 nm) to the telecommunications C-band. By mixing attenuated laser pulses with an average photon number per pulse < 1 with a strong continuous light field at 1403 nm in a periodically poled Zn:LiNbO3 ridge waveguide an internal conversion efficiency of ∼ 73% is achieved. We further investigate the noise properties of the process by measuring the output spectrum. Our results indicate that by narrow spectral filtering a quantum interface should be feasible which bridges the wavelength gap between quantum emitters like color centers in diamond emitting in the red part of the spectrum and low-loss fiber-optic telecommunications wavelengths.

Introduction: The application of a defect-size metal implant for the treatment of focal articular cartilage lesions of the femoral condyle is of potential concern resulting in cartilage damage to opposing biological structures. This in vitro study aims to determine the tibiofemoral contact pressure with a contoured articular partial femoral resurfacing device under continuous dynamic pressure loads., Methods: Peak and area contact pressures were determined in eight fresh-frozen cadaveric specimens using a pressure-sensitive sensor placed in the medial compartment above the menisci. All knees were tested in the untreated condition and after implantation of the prosthetic device in the weight-bearing area of the medial femoral condyle. A robotic knee simulator was used to test each knee under continuous pressure load for 400 s during 40 dynamic knee bending cycles (5°-45° flexion) with body weight ground reaction force (GRF). The GRF was adjusted to the living body weight of the cadaver donor and maintained throughout all cycles., Results: Comparison of the untreated condition to focal inlay resurfacing showed no statistically significant differences (P ≤ 0.05) between all testing conditions. The average maximum peak contact pressure across all 40 flexion cycles increased by 5.1% after resurfacing compared to the untreated knees. The average area contact pressure essentially stayed the same (+0.9%)., Conclusion: The data suggest that resurfacing with the contoured articular prosthetic device does not pose any immediate deleterious effects to the opposing surfaces based on peak and area contact pressure in a continuous dynamic in vitro application. However, long-term in vivo effects remain to be evaluated.

We determined whether the early improvement in symptoms and function after microfracture in the management of articular cartilage defects of the talus is maintained at mid term follow-up. Factors influencing outcome and postoperative magnetic resonance imaging were also evaluated. We performed data collection prospectively using the Hannover Scoring System for the ankle (HSS) and a Visual Analog Scale (VAS) for pain and function preoperatively, at 1 +/- 0.1 year (45 ankles), 2 +/- 0.4 years (45 ankles), and at an average of 5.8 +/- 2.0 years (39 ankles) postoperatively. MRI was used to assess cartilage repair tissue based on the following variables: degree of defect repair and filling of the defect, integration to border zone, surface of the repair tissue, structure of the repair tissue and subchondral bone alterations. Comparing the outcome scores of the last follow-up to the previous follow-up points, the HSS and the VAS (pain, function and satisfaction) showed no deterioration. Four ankles, however, underwent further surgery to address the chondral defect and were regarded as failures. A body mass index greater than 25 kg/m(2) and having severe post-traumatic cartilage damage appeared to be negative prognostic factors. Results for patients older than 50 years were not inferior to those in younger patients. Microfracture arthroplasty induces repair of localized articular cartilage defects of the talus maintaining the encouraging early results at mid term follow-up.

Introduction: Even in a well-aligned total knee arthroplasty (TKA), limb rotation at the time of radiographic assessment will alter the measurement of alignment. This could influence the radiographic outcome of TKA. The purpose of this study was to evaluate the effect of limb rotation on radiographic alignment after TKA and to establish a re-calculation of this rotation by using existing radiographic landmarks., Materials and Methods: Synthetic femur and tibia (Sawbones), Inc. Vashon Island, WA) were used to create a TKA of the Triathlon knee prosthesis system (Stryker), Limerick, Ireland). The femoral alignment was 6.5 degrees valgus. The model was fixed in an upright stand. Five series of nine anteroposterior (AP) long leg radiographs were taken on a 30 cm x 120 cm plates in full extension with the limb rotated, in 5 degrees increments, from 20 degrees external rotation to 20 degrees internal rotation. After digitizing each radiograph (Scanner Hewlett Packard XJ 527), an observer measured the anatomic mechanical angle of the femur [AMA ( degrees )], the mechanical lateral proximal femur angle [mLPFA ( degrees )], the mechanical lateral distal femur angle [mLDFA ( degrees )], the mechanical medial proximal tibia angle [mMPTA ( degrees )] and the mechanical lateral distal tibia angle [mLDTA ( degrees )] using a digital measurement software (MediCAD, Hectec, Altfraunhofen, Germany). Besides, the observer measured the geometrical distances of the femoral component figured on the long leg radiograph. A ratio of one distance to another was measured (called femoral component distance ratio)., Results: The average radiographic anatomic alignment ranged from 6.827 degrees AMA (SD = 0.22 degrees ) in 20 degrees internal rotation to 4.627 degrees AMA (SD = 0.22 degrees ) in 20 degrees external rotation. Average mLPFA ( degrees ) ranged from 101.63 degrees (SD = 0.63) in 20 degrees internal rotation to 93.60 degrees (SD = 0.74 degrees ) in 20 degrees external rotation. Average mLDFA ( degrees ) ranged from 90.59 degrees (SD = 3.01 degrees ) in 20 degrees internal rotation to 86.76 degrees (SD = 0.36 degrees ) in 20 degrees external rotation. Average mMPTA ( degrees ) ranged from 90.35 degrees (SD = 0.81 degrees ) in 20 degrees internal rotation to 88.49 degrees (SD = 0.52 degrees ) in 20 degrees external rotation. Average mLDTA ( degrees ) ranged from 98.89 degrees (SD = 2.3 degrees ) in 20 degrees internal rotation to 90.53 degrees (SD = 3.39 degrees ) in 20 degrees external rotation. Without an application of limb rotation, the femoral component distance ratio was measured to be 0.89 (SD = 0.01), in 20 degrees internal rotation 0.63 (SD = 0.01) and in 20 degrees external rotation 1.16 (SD = 0.01)., Discussion: Limb rotation had a highly statistically significant effect on measured anatomic alignment and mechanical angles. A correlation between limb rotation, anatomic mechanical angle, mechanical angles measured at femur and tibia and the femoral component distance ratio was established. As the anatomic mechanical angle and the femoral component distance ratio change linearly in the range of 20 degrees internal and external limb rotation, a calculation of the femoral component distance ratio could be used to re-calculate the limb rotation at the time of radiographic assessment to evaluate the evidence of a long leg radiograph.

Introduction: When highly conforming polyethylene inlays were introduced into total knee arthroplasty (TKA), they were characterized as adding anteroposterior stability to the reconstructed knee. The aim of this study was to examine the patellofemoral pressure with the designs of a highly conforming and a posterior stabilized inlay. The patellofemoral pressure depends among other factors on the anteroposterior stability of the knee joint., Materials and Methods: Eight fresh frozen human knee specimens underwent testing in a kinematic device. Knee motion was driven by a hydraulic cylinder at an extension moment of 31 Nm. The patellofemoral contact pressure was measured using a pressure sensitive film (Tekscan((R)), Inc., Boston, USA). First, this was assessed after implantation of a cruciate retaining (CR) TKA with a highly conforming polyethylene insert before and after resection of the posterior cruciate ligament. After that, the same measurements were performed with a similar posterior stabilized prosthesis., Results: Patellofemoral contact pressures in the CR prosthesis using the highly conforming inlay were not significantly different before and after resection of the posterior cruciate ligament. However, after implantation of a posterior stabilized prosthesis peak pressure was significantly lower [Mean: 6.12, (SD 2.37) MPa] in comparison to the highly conforming type [7.12, (SD 2.53) MPa, P < 0.01] at a preserved posterior cruciate ligament. Further to that, the mean contact pressure turned out to be lower with the posterior stabilized design (P < 0.006)., Conclusion: The results of this study suggest that a posterior stabilized prosthesis design reduces the patellofemoral peak and mean pressure in comparison with a high conforming design. The better reproducible femoral rollback with a posterior stabilized model at a tibial ventral shift could serve as a possible explanation.

Purpose: Decreased quadriceps strength and fatigue is suspected to be one of the contributing factors for anterior knee pain and malfunction after total knee arthroplasty (TKA). The purpose of this in vitro study was to investigate the amount of quadriceps force required to extend the knee isokinetically after TKA in dependence of different prosthesis designs and the state of the posterior cruciate ligament (PCL)., Materials and Methods: Eight fresh frozen human knee specimens underwent testing in a kinematic device simulating an isokinetic knee extension cycle from 120° of flexion to full extension. The quadriceps force was measured after implantation of a cruciate retaining (CR) TKA (Genesis II, Smith&Nephew, Memphis, TN, USA) applying a conventional CR (11 mm) and a highly conforming (deep dished, DD) polyethylene (PE) inlay consecutively before and after resection of the PCL. Finally, tests were repeated with a posterior-stabilized (PS) design., Results: Simulating a physiological knee extension, no significant differences in the average quadriceps force were detected between the cruciate preserving inlays (CR 1,146.57 ± 88.04 N, DD 1,150.19 ± 97.54 N, P = 0.86) as long as the PCL was intact. After resection of the PCL, the required quadriceps force increased significantly for both designs (CR 1,203.17 ± 91.51 N, P < 0.01 and DD 1,191.88 ± 80.07 N, P < 0.03). After implantation of the posterior stabilized femoral component quad force decreased to its initial levels with forces significantly lower compared to the PCL deficient knees provided with a CR or DD (PS 1,130.91 ± 107.88 N, P < 0.01) inlay. With a deficient PCL there were no statistical differences for the DD design in comparison with CR in mean quad forces (CR 1,203.17 ± 91.51 N vs. DD 1,191.88 ± 80.07 N, P = 0.50) nor in peak forces (CR 1,729.44 ± 161.86 N, DD 1,688.66 ± 123.18 N, P = 0.17)., Discussion: At intact PCL peak quad forces and mean forces beyond 70° of flexion could be shown to be significantly lower with a PS TKA design in comparison with cruciate preserving designs such as CR and DD. In the PCL deficient knee quad forces with a highly conforming implant (DD) and CR were significantly higher than with a PS TKA. The use of PS implants in all PCL deficient knees seems to be advisable

The purpose of the study was to compare a single-row repair and a double-row repair technique for the specific characteristics of a complete subscapularis lesion. Ten pairs of human cadaveric shoulder human shoulder specimens were tested for stiffness and ultimate tensile strength of the intact tendons in a load to failure protocol. After a complete subscapularis tear was provoked, the specimens were assigned to two treatment groups: single-row repair (1) and a double-row repair using a "suture bridge" technique (2). After repair cyclic loading a subsequent load to failure protocol was performed to determine the ultimate tensile load, the stiffness and the elongation behaviour of the reconstructions. The intact subscapularis tendons had a mean stiffness of 115 N/mm and a mean ultimate load of 720 N. The predominant failure mode of the intact tendons was a tear at the humeral insertion site (65%). The double-row technique restored 48% of the ultimate load of the intact tendons (332 N), while the single-row technique revealed a significantly lower ultimate load of 244 N (P = 0.001). In terms of the stiffness, the double-row technique showed a mean stiffness of 81 N/mm which is significantly higher compared to the stiffness of the single-row repairs of 55 N/mm (P = 0.001). The double-row technique has been shown to be stronger and stiffer when compared to a conventional single-row repair. Therefore, this technique is recommended from a biomechanical point of view irrespectively if performed by an open or arthroscopic approach.

Increased patellofemoral contact pressure was described after total knee arthroplasty (TKA). Aim of this in vitro study was to compare the influence of a posterior stabilized (PS) design in comparison to a cruciate retaining (CR) design on patellofemoral contact pressure. Patellofemoral area contact pressure, peak contact pressure and the centre of pressure motion were determined in eight fresh frozen human cadaveric specimens using a Tekscan sensor (K-Scan 4000). A robotic knee simulator was used simulating an isokinetic knee extension cycle from 120 degrees of flexion to full extension. All knees were tested in a first test cycle after implantation of a CR design and in a second test cycle after replacement by a PS design, both using a 11 mm PE inlay (Genesis II, Smith & Nephew, Memphis, TN, USA). The patella remained unresurfaced. A paired sampled t test to compare mean values (significance, P < or = 0.05) was used for statistical analysis. After implantation of the PS design, average patellofemoral area contact pressure was significantly lower (P < or = 0.006) compared with the CR design (PS: 3.58 +/- 1.25 MPa; CR: 4.31 +/- 1.40 MPa). Accordingly, average patellofemoral peak contact pressure decreased significantly (P < or = 0.02) with the PS design (6.12 +/- 2.37 MPa) in comparison with the CR design (7.17 +/- 2.41 MPa). On average, the centre of pressure motion was more physiological with the PS design compared to the CR design over the complete extension cycle. However, this was not significant. In conclusion, the data suggest less patellofemoral contact pressure of a posterior stabilized TKA design in comparison to a cruciate retaining design.

Background: Increased contact stress with a femoral resurfacing prosthesis implanted in the medial femoral condyle and a non-functional meniscus is of concern for potential deleterious effects on tibiofemoral contact mechanics., Methods: Peak contact pressures were determined in seven fresh frozen human cadaveric specimens using a pressure sensitive sensor placed in the medial compartment above the menisci. A knee simulator was used to test each knee in static stance positions (5 degrees/15 degrees/30 degrees/45 degrees) and through 10 dynamic knee flexion cycles (5-45 degrees) with single body weight ground reaction force which was adjusted to the living body weight of the cadaver donor. All specimens were tested in three different conditions: untreated knee (A); flush implantation of a 20mm resurfacing prosthesis (HemiCAP) in the weight bearing area of the medial femoral condyle (B); complete radial tear at the posterior horn of the medial meniscus with the femoral resurfacing device in place (C)., Findings: On average, flush device implantation resulted in no statistically significant differences when compared to the untreated normal knee. The meniscal tear resulted in a significant increase of the mean maximum peak contact pressures by 63%, 57%, and 57% (all P< or =0.05) at 15 degrees , 30 degrees and 45 degrees static stance positions and 78% (P< or =0.05) through the dynamic knee flexion cycle. No significant different maximum peak contact pressures were observed at 5 degrees stance position., Interpretation: Although the condition of a meniscal tear without the resurfacing device could not be compared, possible effects of reduced meniscal tissue and biomechanical integrity of the meniscus must be considered in an in vivo application.

Background: Isolated patellofemoral arthroplasty is discussed controversially. The aim of this nation-wide survey in Germany and review of the literature was to determine the current status of patellofemoral arthroplasty., Methods: A standardised questionnaire was sent to 744 German departments of orthopaedic surgery, traumatology and general surgery. In the first part, surgeons were asked general questions about their department size, case numbers of knee arthroplasties per year and non-endoprosthetic treatment of isolated patellofemoral disorders. If patellofemoral arthroplasty was conducted, parameters concerning age, gender, duration of complaints, indication for surgery, surgical approach, type of endoprosthesis used, additional surgical treatments and failures were evaluated in the second part. Furthermore we asked for the reasons if no isolated patellofemoral arthroplasty was performed. A systematic review of the literature was done including studies published until October 2007. The main inclusion criterion was the presentation of results after the implantation of a patellofemoral prosthesis for isolated patellofemoral osteoarthritis., Results: A total of 225 analysable questionnaires were returned. Of 53,420 knee arthroplasties performed per year, only 195 (0.37 %) were isolated patellofemoral arthroplasties. The majority of patients (91 %) were between 40 and 80 years old. The aetiology of isolated patellofemoral osteoarthritis was believed to be idiopathic in 41 % and traumatic in 8 %. Patellofemoral dysplasia was held to be responsible in 47 % and patellofemoral instability in 4 % of the cases. The main reason for failure and surgical revision was ongoing tibiofemoral osteoarthritis of the affected knee. Negative attitude and disbelief towards the success of isolated patellofemoral arthroplasty were stated by the majority (62 %) of non-users. A lack of appropriate indications was reported by 22 % and lacking know-how by 16 %. We analysed 12 studies (459 implantations; 390 patients) in the literature review. The treatment was considered successful in 67.8 % of cases. The overall revision rate was 30.3 %. The highest failure rates were in patients with progression of tibiofemoral osteoarthritis or malalignment., Conclusions: Isolated patellofemoral arthroplasty has only low significance among surgeons performing knee arthroplasty in Germany. The majority of surgeons do not believe in the success of the procedure. Almost one third of published cases in the literature needed to be revised.

This is a case report of recurrent hemarthrosis of the knee joint over 3 months. The patient, a 47-year-old male had three arthroscopic procedures with multiple joint punctures over a 3-month-period prior to our initial consultation. The first procedure (arthroscopic synovectomy) was done for suspected infection following a series of hyaluronic acid injections. Recurrent hemarthrosis developed subsequent to this. Upon further evaluation, a pseudoaneurysm of the superior middle genicular artery was detected and successfully treated with selective angiographic embolization.

The microfracture technique is an established method for treating articular cartilage lesions of the talus. Symptomatic chondral or osteochondral lesions of grade II or higher with softening or fraying of the chondral surface or an unstable rim are indications for débridement of the lesion and use of the microfracture technique. In advanced degenerative lesions, the indication must be determined critically. In a prospective study, significant (p<0.001) improvement was observed at a mean follow-up of 5.2 years (range 3.8-6.6 years) in 23 ankles. According to the Hannover scoring system, 87% of the patients were rated as excellent or good. Results for patients older than 50 years were not inferior to those for younger patients. Results for overweight patients were significantly (p=0.03) worse compared with patients of normal weight. Magnetic resonance imaging findings revealed that filling of the defect is accomplished in the majority of cases with an inhomogeneous structure of the cartilage repair tissue and a high incidence of subchondral alterations. The microfracture technique appears to be a reliable method for treating chondral and osteochondral lesions of the talus, with good outcomes in a mid-term follow-up.

In contrast to the knee joint, autologous chondrocyte transplantation (ACT) is rarely used for treating articular cartilage lesions in the ankle joint. Matrix-associated autologous chondrocyte transplantation (MACT) with the use of biomaterials as cell carriers has facilitated operative application and fixation within the lesion. We have gained experience in the use of two different MACT techniques. According to the Hannover scoring system for the ankle and visual analog scores, results improved significantly (p

We design photonic crystal microcavities in diamond films for applications in quantum information. Optimization of the cavity design by "gentle confinement" yields a high quality factor Q>66000 and small mode volume V approximately 1.1( l/n)(3). In view of experimental applications we consider the influence of material absorption on the cavity Q factors and present a simple interpretation in the framework of a one-dimensional cavity model.

Many middle-aged patients are affected by localized cartilage defects that are neither appropriate for primary, nor repeat biological repair methods, nor for conventional arthroplasty. This in vitro study aims to determine the peak contact pressure in the tibiofemoral joint with a partial femoral resurfacing device (HemiCAP, Arthrosurface Inc., Franklin, MA, USA). Peak contact pressure was determined in eight fresh-frozen cadaveric specimens using a Tekscan sensor placed in the medial compartment above the menisci. A closed loop robotic knee simulator was used to test each knee in static stance positions (5 degrees /15 degrees /30 degrees /45 degrees ) with body weight ground reaction force (GRF), 30 degrees flexion with twice the body weight (2tBW) GRF and dynamic knee-bending cycles with body weight GRF. The ground reaction force was adjusted to the living body weight of the cadaver donor and maintained throughout all cycles. Each specimen was tested under four different conditions: Untreated, flush HemiCAP implantation, 1-mm proud implantation and 20-mm defect. A paired sampled t test to compare means (significance, P < or = 0.05) was used for statistical analysis. On average, no statistically significant differences were found in any testing condition comparing the normal knee with flush device implantation. With the 1-mm proud implant, statistically significant increase of peak contact pressures of 217% (5 degrees stance), 99% (dynamic knee bending) and 90% (30 degrees stance with 2tBW) compared to the untreated condition was seen. No significant increase of peak contact pressure was evaluated with the 20-mm defect. The data suggests that resurfacing with the HemiCAP does not lead to increased peak contact pressure with flush implantation. However, elevated implantation results in increased peak contact pressure and might be biomechanically disadvantageous in an in vivo application.

Rearrangements of the MALT1 gene by the t(11;18)(q21;q21) and t(14;18)(q32;q21) are the most frequent structural chromosomal abnormalities in MALT lymphomas. These translocations lead to fusions of BIRC3-MALT1 and IGH-MALT1 respectively, and activate the NF-kappaB pathway. Among 122 diffuse large B-cell lymphomas and 28 Burkitt's lymphomas screened by interphase FISH, we found two cases with a break within MALT1, but without a t(11;18) or a t(14;18). Molecular genetic analyses in one of these cases revealed a novel "in frame" fusion of exon 9 of MALT1 and exon 9 of the microtubule-associated protein 4 (MAP4) gene. The translocation was accompanied by a deletion of MALT1 sequences distal to the breakpoint including the caspase-like domain, which is essential for activation of NF-kappaB. As a result of the deletion, the reciprocal 5'MAP4-3'MALT1 transcript was not present, demonstrating that the 5'MALT1-3'MAP4 fusion represents the pathogenetically relevant transcript. Immunohistochemistry with amino-terminal and carboxy-terminal MALT1 antibodies, indicated a strong expression of the chimeric MALT1-MAP4 protein. Moreover, NF-kappaB activation was not increased in this case as shown by the levels of IkappaBalpha phosphorylation and NEMO ubiquitination. Our data demonstrate that the pathogenetic consequences of the novel MALT1-MAP4 fusion are different from those of the known MALT1-associated chromosomal rearrangements and do not involve NF-kappaB activation., ((c) 2006 Wiley-Liss, Inc.)

Based on a real-time measurement of the motion of a single ion in a Paul trap, we demonstrate its electromechanical cooling below the Doppler limit by homodyne feedback control (cold damping). The feedback cooling results are well described by a model based on a quantum mechanical master equation.

Background: The microfracture technique has been used successfully for the treatment of cartilage defects in the knee. The purpose of this study was to evaluate the microfracture technique in the treatment of osteochondral and degenerative chondral defects of the talus., Methods: In a prospective study, 30 ankles in 30 consecutive patients (17 men and 13 women; average age, 41 years; range 20 to 74 years were treated with arthroscopic microfracture. Twenty patients had osteochondral defects and 10 had degenerative chondral defects. Patients were evaluated with clinical examination and MRI preoperatively and at 3, 6, 12, and 24 months postoperatively., Results: At a mean followup of 2 years (range 22 to 27 months), 29 patients were available for follow-up. The results for all ankles according to the Hannover Scoring System were 45% excellent, 38% good, and 17% satisfactory. Results in patients older than 50 years were not inferior to those in younger patients. Visual Analog Score revealed an average of 8 +/- 2 for pain (preoperatively 3 +/- 2; p < or = 0.001), 8 +/- 2 for function (preoperatively 3 +/- 2; p < or = 0.001) and 8 +/- 2 for satisfaction (preoperatively 2 +/- 2; p < or = 0.001). MRI and arthroscopic assessment suggested the presence of cartilage in the microfractured area., Conclusions: At short-term followup, the microfracture technique appeared to repair severe cartilage damage with a good functional outcome. Age was not shown to be a limiting factor.

Teleportation of a quantum state encompasses the complete transfer of information from one particle to another. The complete specification of the quantum state of a system generally requires an infinite amount of information, even for simple two-level systems (qubits). Moreover, the principles of quantum mechanics dictate that any measurement on a system immediately alters its state, while yielding at most one bit of information. The transfer of a state from one system to another (by performing measurements on the first and operations on the second) might therefore appear impossible. However, it has been shown that the entangling properties of quantum mechanics, in combination with classical communication, allow quantum-state teleportation to be performed. Teleportation using pairs of entangled photons has been demonstrated, but such techniques are probabilistic, requiring post-selection of measured photons. Here, we report deterministic quantum-state teleportation between a pair of trapped calcium ions. Following closely the original proposal, we create a highly entangled pair of ions and perform a complete Bell-state measurement involving one ion from this pair and a third source ion. State reconstruction conditioned on this measurement is then performed on the other half of the entangled pair. The measured fidelity is 75%, demonstrating unequivocally the quantum nature of the process.

We report the deterministic creation of maximally entangled three-qubit states-specifically the Greenberger-Horne-Zeilinger (GHZ) state and the W state-with a trapped-ion quantum computer. We read out one of the qubits selectively and show how GHZ and W states are affected by this local measurement. Additionally, we demonstrate conditional operations controlled by the results from reading out one qubit. Tripartite entanglement is deterministically transformed into bipartite entanglement by local operations only. These operations are the measurement of one qubit of a GHZ state in a rotated basis and, conditioned on this measurement result, the application of single-qubit rotations.

An excited-state atom whose emitted light is backreflected by a distant mirror can experience trapping forces, because the presence of the mirror modifies both the electromagnetic vacuum field and the atom's own radiation reaction field. We demonstrate this mechanical action using a single trapped barium ion. We observe the trapping conditions to be notably altered when the distant mirror is translated across an optical wavelength. The well-localized barium ion enables the spatial dependence of the forces to be measured explicitly. The experiment has implications for quantum information processing and may be regarded as the most elementary optical tweezers.

We investigate the spontaneous emission lifetime of a single trapped (40)Ca+ ion placed at different positions in the vacuum standing wave inside a high finesse cavity which is stabilized to the atomic transition. The lifetime is measured by quantum state detection after pi-pulse excitation. The result for the natural lifetime of the D(5/2) metastable state of 1161(22) ms agrees, within 1 standard deviation, with the most precise published value. We observe a reduction of the spontaneous emission lifetime of approximately 15% in the node of the vacuum field.

The microfracture technique has become an established method for the treatment of chondral lesions in the knee. The aim of this study was to determine its usefulness in the treatment of osteochondral (OCL) and degenerative chondral lesions (DCL) of the talus. In a prospective study, 32 patients with an osteochondral lesion (22 patients) or degenerative chondral lesion (10 patients) were operated arthroscopically and treated with the microfracture technique. All patients were evaluated preoperatively as well as 3, 6, 12, and 24 months postoperatively with the Hannover scoring system and a visual analog score (VAS). MRI scans were performed at all points. Statistical analyses were performed using the Wilcoxon sign rank-sum test with a level of significance of p < or = 0.05. At a mean follow-up of 2 years (range: 22-27 months), 23 patients (14 OCL, 9 DCL) were available for follow-up. The average age of the 17 male and 15 female patients at the time of operation was 39 years (range: 16-74 years). The results according to the Hannover scoring system were 43% excellent, 35% good, and 22% satisfactory with 93% excellent or good results for OCL. Older patients (>50 years, n=8) had slightly better results than younger patients. VAS revealed an average of 7.84 (preoperative: 3.53) for pain, 7.85 for function (preoperative; 3.38), and 7.78 for satisfaction (preoperative: 2.41). MRI and arthroscopic assessment showed a visible regeneration of the cartilage in the microfractured area. In a short-term follow-up, the microfracture technique has proven to restore severe cartilage damage with a good functional outcome. Age is not a limiting factor. However, longer-term results remain to be evaluated.

Quantum information processing is performed with single trapped Ca(+) ions, stored in a linear Paul trap and laser-cooled to the ground state of their harmonic quantum motion. Composite laser-pulse sequences were used to implement SWAP gate, phase gate and controlled-NOT gate operations. Stark shifts on the quantum-bit transitions were precisely measured and compensated. For a demonstration of quantum information processing, a Deutsch-Jozsa algorithm has been implemented using two quantum bits encoded on a single ion.

Quantum computers have the potential to perform certain computational tasks more efficiently than their classical counterparts. The Cirac-Zoller proposal for a scalable quantum computer is based on a string of trapped ions whose electronic states represent the quantum bits of information (or qubits). In this scheme, quantum logical gates involving any subset of ions are realized by coupling the ions through their collective quantized motion. The main experimental step towards realizing the scheme is to implement the controlled-NOT (CNOT) gate operation between two individual ions. The CNOT quantum logical gate corresponds to the XOR gate operation of classical logic that flips the state of a target bit conditioned on the state of a control bit. Here we implement a CNOT quantum gate according to the Cirac-Zoller proposal. In our experiment, two 40Ca+ ions are held in a linear Paul trap and are individually addressed using focused laser beams; the qubits are represented by superpositions of two long-lived electronic states. Our work relies on recently developed precise control of atomic phases and the application of composite pulse sequences adapted from nuclear magnetic resonance techniques.

Determining classically whether a coin is fair (head on one side, tail on the other) or fake (heads or tails on both sides) requires an examination of each side. However, the analogous quantum procedure (the Deutsch-Jozsa algorithm) requires just one examination step. The Deutsch-Jozsa algorithm has been realized experimentally using bulk nuclear magnetic resonance techniques, employing nuclear spins as quantum bits (qubits). In contrast, the ion trap processor utilises motional and electronic quantum states of individual atoms as qubits, and in principle is easier to scale to many qubits. Experimental advances in the latter area include the realization of a two-qubit quantum gate, the entanglement of four ions, quantum state engineering and entanglement-enhanced phase estimation. Here we exploit techniques developed for nuclear magnetic resonance to implement the Deutsch-Jozsa algorithm on an ion-trap quantum processor, using as qubits the electronic and motional states of a single calcium ion. Our ion-based implementation of a full quantum algorithm serves to demonstrate experimental procedures with the quality and precision required for complex computations, confirming the potential of trapped ions for quantum computation.

Quantum communication relies on the availability of light pulses with strong quantum correlations among photons. An example of such an optical source is a single-photon pulse with a vanishing probability for detecting two or more photons. Using pulsed laser excitation of a single quantum dot, a single-photon turnstile device that generates a train of single-photon pulses was demonstrated. For a spectrally isolated quantum dot, nearly 100% of the excitation pulses lead to emission of a single photon, yielding an ideal single-photon source.

A small study of surgical patients in one hospital showed that most women preferred single-sex wards. But more than half the men had no preference. Most day-case patients wanted single-sex accommodation. Patients whose stay was seven days or longer showed greater tolerance of mixed-sex wards than others.

In this study, commercial media and kits for identification and tests for antibiotic susceptibility of genital mycoplasmas were evaluated in comparison to standardized methods. A total of 298 specimens was routinely enrolled. Our results showed that all media corresponded for qualitative and semiquantitative identification with a specificity of 100% for both microorganisms and a sensitivity of 94% for U. urealyticum and of 88% for M. hominis. Standard methods were superior to commercial kits for qualitative and quantitative identification (sensitivity 85-97% for U. urealyticum and 79-83% for M. hominis). There were large discrepancies when testing antibiotic susceptibility.

Changes of dental plaque were investigated in Osborne-Mendel-rats under the influence of a sucrose-containing diet as well as the inhibition of it by antibiotics (streptomycin, erythromycin, penicillin) in order to find out the optimal conditions of animal association with Str. mutans (OMZ 176). The cariogenic diet did not alter the isolated total germ numbers, but modified the flora to a streptococcal one. The application of an erythromycin/penicillin mixture caused a 100 fold decrease of the germ number and streptococcal elimination so that an association of the germ Str. mutans detectable by microbiological methods could take place at this moment. The obtained caries scores differed from the non-contaminated group. Mono-associated gnotobiotic Wistar rats developed more carious lesions than conventional animals of the same strain; therefore Str. mutans OMZ 176 was classified as high cariogenic.