Aphid populations are frequently infected with facultative endosymbionts.

The occurrence of facultative endosymbionts has been studied in many commercially important crop pest aphids, but their occurrence and effects in non-commercial aphid species in natural populations have received less attention. We screened 437 aphid samples belonging to 106 aphid species for the eight most common facultative aphid endosymbionts. We found one or more facultative endosymbionts in 53% (56 of 106) of the species investigated. This likely underestimates the situation in the field because facultative endosymbionts are often present in only some colonies of an aphid species. Oligophagous aphid species carried facultative endosymbionts significantly more often than monophagous species. We did not find a significant correlation between ant tending and facultative endosymbiont presence. In conclusion, we found that facultative endosymbionts are common among aphid populations. This study is, to our knowledge, the first of its kind in the Netherlands and provides a basis for future research in this field. For instance, it is still unknown in what way many of these endosymbionts affect their hosts, which is important for determining the importance of facultative endosymbionts to community dynamics.

Outcome after operative treatment for chronic versus acute Achilles tendon rupture - A comparative analysis.

BACKGROUND: This study compared outcomes after treatment of acute Achilles tendon (AT) rupture via percutaneous suturing, with those after chronic AT rupture treated via open reconstruction. METHODS: This retrospective study included 30 patients who underwent either percutaneous suturing for acute AT rupture (group AR, n=16) or open reconstruction for chronic AT rupture (group CR, n=14). Function was evaluated by calf muscle circumference, and endurance through isokinetic measurement and single-leg heel-rise test. Score evaluation included AT Total Rupture Score, Victorian Institute of Sports Assessment-Achilles questionnaire, and visual analogue scale pain score. Postoperative tendon thickness was measured using ultrasonography and MRI. RESULTS: Follow-up was conducted 4.97±1.79 years postoperatively. The groups were similar in age and body mass index. There was no significant difference between groups in calf circumference, isokinetic measurement, heel-rise test, and score evaluation. There was significantly less mediolateral tendon thickening in group AR compared with group CR on ultrasonography (p=0.01) and MRI (p=0.001). CONCLUSIONS: Open reconstruction for chronic AT rupture may result in comparable clinical and functional outcomes, but a thicker tendon compared with percutaneous suturing after acute AT rupture.

One-stage bilateral implantation of a calcar-guided short-stem in total hip arthroplasty : Minimally invasive modified anterolateral approach in supine position.

OBJECTIVE: One-stage bilateral, muscle-preserving, calcar-guided implantation technique through the modified minimally invasive anterolateral approach in supine position. INDICATIONS: Bilateral primary/secondary osteoarthritis of the hip; bilateral femoral head necrosis; ASA I-III. CONTRAINDICATIONS: ASA IV; severe osteoporosis, other factors jeopardizing stable anchorage of cementless, calcar-guided short-stem; infection. SURGICAL TECHNIQUE: Supine position. Skin incision. Opening of fascia; blunt dissection, pushing gluteal muscles dorsally with the index finger. Capsulectomy. Individual osteotomy according to preoperative plan to determine short-stem position. Remove femoral head. Prepare acetabulum. Position cup. Femoral preparation with the curved opening awl. Spare greater trochanter and gluteal muscles. Insert trial rasps in ascending sizes with "round-the-corner" technique. Select offset version, then trial reposition with intraoperative radiograph and implantation of the definitive implant. Wound closure. Consultation with the anesthesiologist to confirm a stable patient. Same procedure on contralateral hip. POSTOPERATIVE MANAGEMENT: Mobilization on day 1 with immediate full weight bearing. Remove wound drains and urinary catheter (only female patients) on day 2. Intensive protocol of physiotherapy and rehabilitation. Thrombosis prophylaxis. Rehabilitation from day 7. RESULTS: Almost 500 patients have undergone surgery since 2010. First consecutive 54 patients (108 hips) prospectively evaluated. After 2 years, Harris Hip Score was 98.8; satisfaction on visual analogue scale was 9.9. Low peri- and postoperative complication rates; no implant revisions. CONCLUSION: The muscle-sparing approach and the special "round-the-corner" technique in one-stage bilateral procedure leads to rapid mobilization and rehabilitation with excellent early clinical results and high satisfaction rates.

[Promoting the next generation - what can we improve?]. / Nachwuchsförderung - Was können wir besser machen.

The surgical faculties are threatened by a shortage of junior staff which also applies to orthopedics and traumatology. This article explains which concepts the Young Forum of the German Society of Orthopedics and Traumatology (DGOU) already actively promotes to get students enthusiastic about musculoskeletal surgery and what additional efforts are needed to ensure that the measures are successful.

Compensating motion artifacts of 3D in vivo SD-OCT scans.

We propose a probabilistic approach for compensating motion artifacts in 3D in vivo SD-OCT (spectral-domain optical coherence tomography) tomographs. Subject movement causing axial image shifting is a major problem for in vivo imaging. Our technique is applied to analyze the tissue at percutaneous implants recorded with SD-OCT in 3D. The key challenge is to distinguish between motion and the natural 3D spatial structure of the scanned subject. To achieve this, the motion estimation problem is formulated as a conditional random field (CRF). For efficient inference, the CRF is approximated by a Gaussian Markov random field. The method is verified on synthetic datasets and applied on noisy in vivo recordings showing significant reduction of motion artifacts while preserving the tissue geometry.