Response of bat species to sylvo-pastoral abandonment

We assessed the effect of abandonment of sylvo-pastoral practices in chestnut orchards (Castanea sativa) on bats in southern Switzerland to determine practical recommendations for bat conservation. We compared bat species richness and foraging activities between traditionally managed and unmanaged chestnut orchards, testing the hypothesis that managed orchards provide better foraging opportunities and harbour more bat species. Echolocation calls of foraging bats were sampled simultaneously at paired sites of managed and unmanaged orchards using custom made recorders. Vegetation structure and aerial insect availability were sampled at the recording sites and used as explanatory variables in the model. In a paired sampling design, we found twice the number of bat species (12) and five times higher total foraging activity in the managed chestnut orchards compared to the unmanaged ones. Bat species with low flight manoeuvrability were 14 times more common in managed orchards, whereas bats with medium to high manoeuvrability were only 5 times more common than in abandoned orchards. The vegetation structure was less dense in managed orchards. However, management did not affect relative insect abundance. Bats primarily visited the most open orchards, free of undergrowth. As a result of restricted access into the overgrown forests, the abandonment of chestnut orchards leads to a decline in bat species richness and foraging activities. Continued management of chestnut orchards to maintain an open structure is important for the conservation of endangered bat species in the southern Swiss Alps.

Évaluation du suivi clinique des prothèses totales du genou [Total knee arthroplasty outcome assessment]

L'évaluation des résultats des arthroplasties totales du genou demande une évaluation du geste thérapeutique ou clinique, mais doit également tenir compte de l'impact de ce geste sur l'état de santé global du patient (somatique, psychologique, social) et intégrer son degré de satisfaction. La complexité croissante des instruments de mesure du suivi a de quoi décourager le chirurgien praticien déjà surchargé par son activité clinique quotidienne. L'apparition des scores, des études prospectives et des analyses statistiques, telles les courbes de survie, ont certainement permis une appréciation plus objective de nos résultats, tout en accroissant nos connaissances et en améliorant notre pratique quotidienne. La question aujourd'hui n'est plus de savoir si un suivi clinique de nos patients est utile, mais plutôt de choisir les bons instruments et de définir les buts de l'analyse tout en cherchant comment implanter cette démarche de manière réaliste dans nos pratiques. Les scores classiques, aussi imparfaits soient-ils, restent pour l'instant utiles. Largement diffusés à travers le monde, appliqués de manière prospective, ces outils de suivi orientés vers la clinique et la radiologie sont le fondement du suivi prospectif des implants. Au quotidien, ils permettent un suivi en temps réel des implants d'un service ou d'une institution. Cependant, leur faiblesse intrinsèque résidant dans l'inaptitude à saisir le point de vue du patient, il semble inéluctable d'y adjoindre des instruments psychométriques. Dans l'avenir, la recherche devrait se concentrer vers le développement d'outils adaptés, capables de cerner avec une plus grande précision l'attente des patients et de technologies accessibles à chaque praticien pour mesurer objectivement les capacités fonctionnelles de leurs patients avec plus d'acuité. Le développement de systèmes permettant une évaluation objective de la fonction quotidienne du patient revêt un intérêt tout particulier. Parallèlement, un effort doit être fait au niveau des sociétés spécialisées nationales et internationales pour harmoniser leurs protocoles de suivi.

Travellers' profile, travel patterns and vaccine practices-a 10-year prospective study in a Swiss Travel Clinic.

BACKGROUND: The travel clinic in Lausanne serves a catchment area of 700 000 of inhabitants and provides pre- and post-travel consultations. This study describes the profile of attendees before departure, their travel patterns and the travel clinic practices in terms of vaccination over time. METHODS: We included all pre-travel first consultation data recorded between November 2002 and December 2012 by a custom-made program DIAMM/G. We analysed client profiles, travel characteristics and vaccinations prescribed over time. RESULTS: Sixty-five thousand and forty-six client-trips were recorded. Fifty-one percent clients were female. Mean age was 32 years. In total, 0.1% were aged <1 year and 0.2% ≥80 years. Forty-six percent of travellers had pre-existing medical conditions. Forty-six percent were travelling to Africa, 35% to Asia, 20% to Latin America and 1% (each) to Oceania and Europe; 19% visited more than one country. India was the most common destination (9.6% of travellers) followed by Thailand (8.6%) and Kenya (6.4%). Seventy-three percent of travellers were planning to travel for ≤ 4 weeks. The main reasons for travel were tourism (75%) and visiting friends and relatives (18%). Sixteen percent were backpackers. Pre-travel advice were sought a median of 29 days before departure. Ninety-nine percent received vaccine(s). The most frequently administered vaccines were hepatitis A (53%), tetanus-diphtheria (46%), yellow fever (39%), poliomyelitis (38%) and typhoid fever (30%). CONCLUSIONS: The profile of travel clinic attendees was younger than the general Swiss population. A significant proportion of travellers received vaccinations that are recommended in the routine national programme. These findings highlight the important role of travel clinics to (i) take care of an age group that has little contact with general practitioners and (ii) update vaccination status. The most commonly prescribed travel-related vaccines were for hepatitis A and yellow fever. The question remains to know whether clients do attend travel clinics because of compulsory vaccinations or because of real travel health concern or both.

Desensitization of thermal hyperemia in the skin is reproducible.

OBJECTIVE: Local heating increases skin blood flow SkBF (thermal hyperemia). In a previous study, we reported that a first local thermal stimulus could attenuate the hyperemic response to a second one applied later on the same skin spot, a phenomenon that we termed desensitization. However, other studies found no evidence for desensitization in similar conditions. The aim of the present work was to test whether it was related to differences in instrumentation. METHODS: Twenty-eight healthy young males were studied. Two pairs of heating chambers, one custom-made (our study) and one commercial (other groups), were affixed to forearm skin. SkBF was measured with single-point laser-Doppler flowmetry (LDF) (780nm) in one pair, and laser-Doppler imaging (LDI) (633nm) in the other. A temperature step from 34 to 41°C, was applied for 30minutes and repeated after two hours. RESULTS: During the second thermal challenge, the plateau SkBF was lower than during the first thermal and was observed with each of the four combinations of SkBF measurement techniques and heating equipment (p<0.05 for all conditions, range -9% to -16% of the initial value). CONCLUSION: Desensitization of thermal hyperemia is not specific to peculiar operating conditions.

New bench test for venous cannula performance assessment.

Cannula design is of prime importance for venous drainage during cardiopulmonary bypass (CPB). To evaluate cannulas intended for CPB, an in vitro circuit was set up with silicone tubing between the test cannula encased in a movable preload reservoir and another static reservoir. The pressure-drop (DeltaP) value (P-drainage - P-preload) was measured using Millar pressure transducers. Flow rate (Q) was measured using an ultrasound flowmeter. Data display and data recording were controlled using a LabView application, custom made particularly for our experiments. Our results demonstrated that DeltaP, Q, and cannula resistance (DeltaP/Q) values were significantly decreased when the cannula diameter was increased for Smart and Medtronic cannulas. Smartcanula showed 36% and 43% less resistance compared to Medtronic venous and Medtronic femoral cannulas, respectively. The cannula shape (straight- or curved-tips) did not affect the DLP cannula resistance. Out of five cannulas tested, the Smartcanula outperforms the other commercially available cannulas. The mean (DeltaP/Q) values were 3.3 +/- 0.08, 4.07 +/- 0.08, 5.58 +/- 0.10, 5.74 +/- 0.15, and 6.45 +/- 0.15 for Smart, Medtronic, Edwards, Sarns, and Gambro cannulas, respectively (two-way ANOVA, p < 0.0001). In conclusion, the present assay allows discrimination between different forms of cannula with high or low lumen resistance.

Genome-Wide Analysis of Salicylate and Dibenzofuran Metabolism in Sphingomonas Wittichii RW1.

Sphingomonas wittichii RW1 is a bacterium isolated for its ability to degrade the xenobiotic compounds dibenzodioxin and dibenzofuran (DBF). A number of genes involved in DBF degradation have been previously characterized, such as the dxn cluster, dbfB, and the electron transfer components fdx1, fdx3, and redA2. Here we use a combination of whole genome transcriptome analysis and transposon library screening to characterize RW1 catabolic and other genes implicated in the reaction to or degradation of DBF. To detect differentially expressed genes upon exposure to DBF, we applied three different growth exposure experiments, using either short DBF exposures to actively growing cells or growing them with DBF as sole carbon and energy source. Genome-wide gene expression was examined using a custom-made microarray. In addition, proportional abundance determination of transposon insertions in RW1 libraries grown on salicylate or DBF by ultra-high throughput sequencing was used to infer genes whose interruption caused a fitness loss for growth on DBF. Expression patterns showed that batch and chemostat growth conditions, and short or long exposure of cells to DBF produced very different responses. Numerous other uncharacterized catabolic gene clusters putatively involved in aromatic compound metabolism increased expression in response to DBF. In addition, only very few transposon insertions completely abolished growth on DBF. Some of those (e.g., in dxnA1) were expected, whereas others (in a gene cluster for phenylacetate degradation) were not. Both transcriptomic data and transposon screening suggest operation of multiple redundant and parallel aromatic pathways, depending on DBF exposure. In addition, increased expression of other non-catabolic genes suggests that during initial exposure, S. wittichii RW1 perceives DBF as a stressor, whereas after longer exposure, the compound is recognized as a carbon source and metabolized using several pathways in parallel.

Do orthopaedic shoes improve local dynamic stability of gait? An observational study in patients with chronic foot and ankle injuries.

BACKGROUND: Complex foot and ankle fractures, such as calcaneum fractures or Lisfranc dislocations, are often associated with a poor outcome, especially in terms of gait capacity. Indeed, degenerative changes often lead to chronic pain and chronic functional limitations. Prescription footwear represents an important therapeutic tool during the rehabilitation process. Local Dynamic Stability (LDS) is the ability of locomotor system to maintain continuous walking by accommodating small perturbations that occur naturally during walking. Because it reflects the degree of control over the gait, LDS has been advocated as a relevant indicator for evaluating different conditions and pathologies. The aim of this study was to analyze changes in LDS induced by orthopaedic shoes in patients with persistent foot and ankle injuries. We hypothesised that footwear adaptation might help patients to improve gait control, which could lead to higher LDS: METHODS: Twenty-five middle-aged inpatients (5 females, 20 males) participated in the study. They were treated for chronic post-traumatic disabilities following ankle and/or foot fractures in a Swiss rehabilitation clinic. During their stay, included inpatients received orthopaedic shoes with custom-made orthoses (insoles). They performed two 30s walking trials with standard shoes and two 30s trials with orthopaedic shoes. A triaxial motion sensor recorded 3D accelerations at the lower back level. LDS was assessed by computing divergence exponents in the acceleration signals (maximal Lyapunov exponents). Pain was evaluated with Visual Analogue Scale (VAS). LDS and pain differences between the trials with standard shoes and the trials with orthopaedic shoes were assessed. RESULTS: Orthopaedic shoes significantly improved LDS in the three axes (medio-lateral: 10% relative change, paired t-test p < 0.001; vertical: 9%, p = 0.03; antero-posterior: 7%, p = 0.04). A significant decrease in pain level (VAS score -29%) was observed. CONCLUSIONS: Footwear adaptation led to pain relief and to improved foot & ankle proprioception. It is likely that that enhancement allows patients to better control foot placement. As a result, higher dynamic stability has been observed. LDS seems therefore a valuable index that could be used in early evaluation of footwear outcome in clinical settings.

Correlations between trabecular bone score, measured using anteroposterior dual-energy x-ray absorptiometry acquisition, and 3-dimensional parameters of bone microarchitecture: an experimental study on human cadaver vertebrae.

Developing a novel technique for the efficient, noninvasive clinical evaluation of bone microarchitecture remains both crucial and challenging. The trabecular bone score (TBS) is a new gray-level texture measurement that is applicable to dual-energy X-ray absorptiometry (DXA) images. Significant correlations between TBS and standard 3-dimensional (3D) parameters of bone microarchitecture have been obtained using a numerical simulation approach. The main objective of this study was to empirically evaluate such correlations in anteroposterior spine DXA images. Thirty dried human cadaver vertebrae were evaluated. Micro-computed tomography acquisitions of the bone pieces were obtained at an isotropic resolution of 93μm. Standard parameters of bone microarchitecture were evaluated in a defined region within the vertebral body, excluding cortical bone. The bone pieces were measured on a Prodigy DXA system (GE Medical-Lunar, Madison, WI), using a custom-made positioning device and experimental setup. Significant correlations were detected between TBS and 3D parameters of bone microarchitecture, mostly independent of any correlation between TBS and bone mineral density (BMD). The greatest correlation was between TBS and connectivity density, with TBS explaining roughly 67.2% of the variance. Based on multivariate linear regression modeling, we have established a model to allow for the interpretation of the relationship between TBS and 3D bone microarchitecture parameters. This model indicates that TBS adds greater value and power of differentiation between samples with similar BMDs but different bone microarchitectures. It has been shown that it is possible to estimate bone microarchitecture status derived from DXA imaging using TBS.

Off-pump transapical mitral valve-in-ring implantation.

OBJECTIVES: The study aimed to evaluate the feasibility of off-pump transapical mitral valve-in-ring implantation and to test the performance of a custom-made self-expandable stent valve, in comparison with the standard SAPIEN valve. METHODS: Acute experiments were performed in five pigs. Animals (mean weight 58.4 ± 7.3 kg) underwent mitral valve annuloplasties under cardiopulmonary bypass using 26-mm rings (SJM?). Then, a 30-mm custom-made self-expandable stent valve or a 23-mm balloon-expandable transcatheter heart valve (Edwards SAPIEN XT?) was deployed within the annuloplasty rings through a transatrial access and under direct vision. Subsequently, the stent valves were inserted transapically under fluoroscopic guidance and off pump. RESULTS: The procedural success of transatrial and transapical mitral valve-in-ring procedures was 100% (10 of 10). Mean transatrial and transapical procedure time was 2.0 ± 1.1 and 22.0 ± 5.7 min, respectively. Haemodynamic status during transapical implantation remained stable, and differences in data collected before and after the stent-valve deployment were not statistically significant. Mean mitral annulus diameter and mean mitral orifice area in the group of self-expandable stent valves were 2.60 ± 0.02 cm and 4.16 ± 0.48 cm(2), respectively, whereas in the SAPIEN group they were 1.95 ± 0.18 cm and 2.26 ± 0.20 cm(2), respectively. Trace or mild regurgitation was detected only in the self-expandable stent-valve group. Mean gradients were 4.1 ± 4.5 mmHg across the self-expandable stent valves and 1.0 ± 0 mmHg across the SAPIEN valves. Postmortem examination confirmed adequate positioning of the self-expandable valves and the SAPIEN valves within the annuloplasty ring. CONCLUSIONS: Off-pump transapical mitral valve-in-ring implantation is safe and feasible. Transapical access may represent the ideal option for valve-in-ring procedures in cases of recurrent mitral regurgitation after mitral valve repair, in high-risk patients. Owing to the supra-annular profile of the valve components, our custom-made nitinol stent valve provides nearer to normal functional area than the SAPIEN valve.

Diagnosis of periprosthetic joint infections.

Advances in implant design, surgical technique, peri-operative antimicrobial prophylaxis and laminar airflow operating room environment have made total joint arthroplasty one of the most successful surgical procedures of all times. Orthopaedic implants, however, remain prone to microbial contamination resulting in persistent risk of implant-associated infection. Treatment of infections associated with orthopaedic devices usually requires appropriate surgical intervention combined with a prolonged antimicrobial therapy. The choice of the best possible treatment regimen depends on duration and pathogenesis of infection, stability of the implant, antimicrobial susceptibility of the pathogen and condition of the surrounding soft tissue. In addition towell known diagnostic procedures new promising tools for rapid and correct microbial diagnosis are being developed as correct diagnosis of the responsible micro-organism and this is paramount for successful treatment of prosthetic joint infection.

Update on the non-prewhitening model observer in computed tomography for the assessment of the adaptive statistical and model-based iterative reconstruction algorithms.

The state of the art to describe image quality in medical imaging is to assess the performance of an observer conducting a task of clinical interest. This can be done by using a model observer leading to a figure of merit such as the signal-to-noise ratio (SNR). Using the non-prewhitening (NPW) model observer, we objectively characterised the evolution of its figure of merit in various acquisition conditions. The NPW model observer usually requires the use of the modulation transfer function (MTF) as well as noise power spectra. However, although the computation of the MTF poses no problem when dealing with the traditional filtered back-projection (FBP) algorithm, this is not the case when using iterative reconstruction (IR) algorithms, such as adaptive statistical iterative reconstruction (ASIR) or model-based iterative reconstruction (MBIR). Given that the target transfer function (TTF) had already shown it could accurately express the system resolution even with non-linear algorithms, we decided to tune the NPW model observer, replacing the standard MTF by the TTF. It was estimated using a custom-made phantom containing cylindrical inserts surrounded by water. The contrast differences between the inserts and water were plotted for each acquisition condition. Then, mathematical transformations were performed leading to the TTF. As expected, the first results showed a dependency of the image contrast and noise levels on the TTF for both ASIR and MBIR. Moreover, FBP also proved to be dependent of the contrast and noise when using the lung kernel. Those results were then introduced in the NPW model observer. We observed an enhancement of SNR every time we switched from FBP to ASIR to MBIR. IR algorithms greatly improve image quality, especially in low-dose conditions. Based on our results, the use of MBIR could lead to further dose reduction in several clinical applications.

Radiographic volume analysis as a novel tool to determine nasopalatine duct cyst dimensions and its association with presenting symptoms and postoperative complications.

OBJECTIVES: The aims of the study were to use cone beam computed tomography (CBCT) images of nasopalatine duct cysts (NPDC) and to calculate the diameter, surface area, and 3D-volume using a custom-made software program. Furthermore, any associations of dimensions of NPDC with age, gender, presence/absence of maxillary incisors/canines (MI/MC), endodontic treatment of MI/MC, presenting symptoms, and postoperative complications were evaluated. MATERIAL AND METHODS: The study comprised 40 patients with a histopathologically confirmed NPDC. On preoperative CBCT scans, curves delineating the cystic borders were drawn in all planes and the widest diameter (in millimeter), surface area (in square millimeter), and volume (in cubic millimeter) were calculated. RESULTS: The overall mean cyst diameter was 15 mm (range 7-47 mm), the mean cyst surface area 566 mm(2) (84-4,516 mm(2)), and the mean cyst volume 1,735 mm(3) (65-25,350 mm(3)). For 22 randomly allocated cases, a second measurement resulted in a mean absolute aberration of ±4.2 % for the volume, ±2.8 % for the surface, and ±4.9 % for the diameter. A statistically significant association was found for the CBCT determined cyst measurements and the need for preoperative endodontic treatment to MI/MC and for postoperative complications. CONCLUSION: In the hands of a single experienced operator, the novel software exhibited high repeatability for measurements of cyst dimensions. Further studies are needed to assess the application of this tool for dimensional analysis of different jaw cysts and lesions including treatment planning. CLINICAL RELEVANCE: Accurate radiographic information of the bone volume lost (osteolysis) due to expansion of a cystic lesion in three dimensions could help in personalized treatment planning.

Traitement de la coxarthrose par des prothèses totales de hanche sur mesure [Treatment of coxarthrosis with fitted total hip prostheses replacement]

The treatment of hip osteoarthritis with total hip arthroplasty has continuously evolved since it was first introduced in the sixties. The problem of aseptic loosening of the cemented prostheses, mainly in young active patients, has stimulated two different types of research: on one side the improvement of cementing techniques and on the other side the development of cementless osteoinegrable implants. We discuss the problems of these cementless hip prostheses. Recently published anatomic and biomechanic studies have led to the development of personalized custom femoral stems for each patient. The conception technique and first clinical results are described.

An intramedullary alignment guide lodging within the femoral canal during total knee arthroplasty: a case report.

The usual complications of total knee arthroplasty include thrombo-embolism, infection, and loosening. We report an unusual and potentially serious complication of an intramedullary guide lodging within the femoral canal during the procedure. Considering the risk of fracture and additional exposure, the guide was not removed and was cut in situ. The rest of the operation was completed successfully and the patient made an uneventfully recovery.

Analysis of joint laxity after total ankle arthroplasty: cadaver study.

BACKGROUND: Clinical results of total ankle arthroplasty with early designs were disappointing. Recently-developed ankle prostheses have good mid-term results; however, limited information is available regarding effects of total ankle arthroplasty on ankle laxity. METHODS: Eight cadaveric lower extremities were tested with a custom device which enabled measurement of multi-axial forces, moments, and displacement during applied axial, shear, and rotational loading. Tests consisted of anterior-posterior and medial-lateral translation and internal-external rotation of the talus relative to the tibia during axial loads on the tibia simulating body weight (700 N) and an unloaded condition (5 N). Tests were performed in neutral, dorsiflexion, and plantarflexion. Laxity was determined for the intact ankle, and following insertion of an unconstrained total ankle implant, comparing load-displacement curve. FINDINGS: Laxity after total ankle arthroplasty did not approximate the normal ankle in most conditions tested. Displacement was significantly greater for total ankle arthroplasty in both posterior and lateral translation, and internal rotation, with 5 N axial loading, and anterior-posterior, medial-lateral translation, and internal-external rotation for 700 N axial loading. For the 700 N axial load condition, in the neutral ankle position, total anterior-posterior translation averaged 0.4 mm (SD 0.2 mm), but 6.0 mm (SD 1.5 mm) after total ankle arthroplasty (P<0.01). This study demonstrated more laxity in the replaced ankle than normal ankle for both unloaded and 700 N axially loaded conditions. INTERPRETATION: These data indicate the increased responsibility of the ligaments for ankle laxity after total ankle arthroplasty and suggest the importance of meticulous ligament reconstruction with total ankle arthroplasty operations.