First Tarsometatarsal Joint Fusion in Foot-A Biomechanical Human Anatomical Specimen Analysis with Use of Low-Profile Nitinol Staples Acting as Continuous Compression Implants.

Background and Objectives: The aim of this study was to investigate under dynamic loading the potential biomechanical benefit of simulated first tarsometatarsal (TMT-1) fusion with low-profile superelastic nitinol staples used as continuous compression implants (CCIs) in two different configurations in comparison to crossed screws and locked plating in a human anatomical model. Materials and Methods: Thirty-two paired human anatomical lower legs were randomized to four groups for TMT-1 treatment via: (1) crossed-screws fixation with two 4.0 mm fully threaded lag screws; (2) plate-and-screw fixation with a 4.0 mm standard fully threaded cortex screw, inserted axially in lag fashion, and a 6-hole TMT-1 Variable-Angle (VA) Fusion Plate 2.4/2.7; (3) CCI fixation with two two-leg staples placed orthogonally to each other; (4) CCI fixation with one two-leg staple and one four-leg staple placed orthogonally to each other. Each specimen was biomechanically tested simulating forefoot weightbearing on the toes and metatarsals. The testing was performed at 35-37 °C under progressively increasing cyclic axial loading until construct failure, accompanied by motion tracking capturing movements in the joints. Results: Combined adduction and dorsiflexion movement of the TMT-1 joint in unloaded foot condition was associated with no significant differences among all pairs of groups (p ≥ 0.128). In contrast, the amplitude of this movement between unloaded and loaded foot conditions within each cycle was significantly bigger for the two CCI fixation techniques compared to both crossed-screws and plate-and-screw techniques (p ≤ 0.041). No significant differences were detected between the two CCI fixation techniques, as well as between the crossed-screws and plate-and-screw techniques (p ≥ 0.493) for this parameter of interest. Furthermore, displacements at the dorsal and plantar aspects of the TMT-1 joint in unloaded foot condition, together with their amplitudes, did not differ significantly among all pairs of groups (p ≥ 0.224). Conclusions: The low-profile superelastic nitinol staples demonstrate comparable biomechanical performance to established crossed-screws and plate-and-screw techniques applied for fusion of the first tarsometatarsal joint.

The dynamics of molecular, immune and physiological features of the host and the gut microbiome, and their interactions before and after onset of laying in two hen strains.

Aggregation of data, including deep sequencing of mRNA and miRNA data in jejunum mucosa, abundance of immune cells, metabolites, or hormones in blood, composition of microbiota in digesta and duodenal mucosa, and production traits collected along the lifespan, provides a comprehensive picture of lifelong adaptation processes. Here, respective data from two laying hen strains (Lohmann Brown-Classic (LB) and Lohmann LSL-Classic (LSL) collected at 10, 16, 24, 30, and 60 wk of age were analyzed. Data integration revealed strain- and stage-specific biosignatures, including elements indicative of molecular pathways discriminating the strains. Although the strains performed the same, they differed in the activity of immunological and metabolic functions and pathways and showed specific gut-microbiota-interactions in different production periods. The study shows that both strains employ different strategies to acquire and maintain their capabilities under high performance conditions, especially during the transition phase. Furthermore, the study demonstrates the capacity of such integrative analyses to elucidate molecular pathways that reflect functional biodiversity. The bioinformatic reduction of the multidimensional data provides good guidance for further manual review of the data.

The active core microbiota of two high-yielding laying hen breeds fed with different levels of calcium and phosphorus.

The nutrient availability and supplementation of dietary phosphorus (P) and calcium (Ca) in avian feed, especially in laying hens, plays a vital role in phytase degradation and mineral utilization during the laying phase. The required concentration of P and Ca peaks during the laying phase, and the direct interaction between Ca and P concentration shrinks the availability of both supplements in the feed. Our goal was to characterize the active microbiota of the entire gastrointestinal tract (GIT) (crop, gizzard, duodenum, ileum, caeca), including digesta- and mucosa-associated communities of two contrasting high-yielding breeds of laying hens (Lohmann Brown Classic, LB; Lohmann LSL-Classic, LSL) under different P and Ca supplementation levels. Statistical significances were observed for breed, GIT section, Ca, and the interaction of GIT section x breed, P x Ca, Ca x breed and P x Ca x breed (p < 0.05). A core microbiota of five species was detected in more than 97% of all samples. They were represented by an uncl. Lactobacillus (average relative abundance (av. abu.) 12.1%), Lactobacillus helveticus (av. abu. 10.8%), Megamonas funiformis (av. abu. 6.8%), Ligilactobacillus salivarius (av. abu. 4.5%), and an uncl. Fusicatenibacter (av. abu. 1.1%). Our findings indicated that Ca and P supplementation levels 20% below the recommendation have a minor effect on the microbiota compared to the strong impact of the bird's genetic background. Moreover, a core active microbiota across the GIT of two high-yielding laying hen breeds was revealed for the first time.

Multi-Omics Reveals Different Strategies in the Immune and Metabolic Systems of High-Yielding Strains of Laying Hens.

Lohmann Brown (LB) and Lohmann Selected Leghorn (LSL) are two commercially important laying hen strains due to their high egg production and excellent commercial suitability. The present study integrated multiple data sets along the genotype-phenotype map to better understand how the genetic background of the two strains influences their molecular pathways. In total, 71 individuals were analyzed (LB, n = 36; LSL, n = 35). Data sets include gut miRNA and mRNA transcriptome data, microbiota composition, immune cells, inositol phosphate metabolites, minerals, and hormones from different organs of the two hen strains. All complex data sets were pre-processed, normalized, and compatible with the mixOmics platform. The most discriminant features between two laying strains included 20 miRNAs, 20 mRNAs, 16 immune cells, 10 microbes, 11 phenotypic traits, and 16 metabolites. The expression of specific miRNAs and the abundance of immune cell types were related to the enrichment of immune pathways in the LSL strain. In contrast, more microbial taxa specific to the LB strain were identified, and the abundance of certain microbes strongly correlated with host gut transcripts enriched in immunological and metabolic pathways. Our findings indicate that both strains employ distinct inherent strategies to acquire and maintain their immune and metabolic systems under high-performance conditions. In addition, the study provides a new perspective on a view of the functional biodiversity that emerges during strain selection and contributes to the understanding of the role of host-gut interaction, including immune phenotype, microbiota, gut transcriptome, and metabolome.

Effects on the Ileal Microbiota of Phosphorus and Calcium Utilization, Bird Performance, and Gender in Japanese Quail.

In this study, we aimed to investigate the ileum digesta of a large cohort of Japanese quail fed the same diet, with similar environmental conditions. We also address how P utilization (PU), Ca utilization (CaU), and bird performance (feed intake (FI), feed conversion (FC), and body weight gain (BWG)) modify intestinal microbiota of male and female quail. Despite the great number of samples analyzed (760), a core microbiome was composed of five bacteria. The Unc. Lactobacillus, Unc. Clostridaceae 1, Clostridium sensu stricto, Escherichia coli, and Streptococcus alactolyticus were detected in all samples and contributed to more than 70% of the total community. Depending on the bird predisposition for PU, CaU, FI, BWG, and FC, those species were present in higher or lower abundances. There was a significant gender effect on the ileal microbial community. While females had higher abundances of Lactobacillus, males were more colonized by Streptococcus alactolyticus. The entire cohort was highly colonized by Escherichia coli (8%-15%), an enteropathogenic bacteria. It remains unclear, if microbiota composition followed the mechanisms that caused different PU, CaU, FI, FC, and BWG or if the change in microbiota composition and function caused the differences in PU, CaU, and performance traits.

Endovascular therapy versus thrombolysis in patients with anterior circulation stroke in everyday clinical practice.

BACKGROUND: In patients with large vessel occlusions, endovascular treatment has been shown to be superior to intravenous thrombolysis in recent trials. AIMS: The aim of this study was to analyze the impact of endovascular treatment on clinical and radiological outcome in everyday clinical practice. METHODS: We compared the rates of good outcome (modified Rankin scale ≤ 2 at discharge), in-hospital death, symptomatic intracranial hemorrhages, and infarct sizes in patients with distal intracranial carotid artery, M1 and M2 occlusions during two time periods. RESULTS: From January 2008 to October 2012, a total of 509 patients were treated with intravenous thrombolysis and from November 2012 to December 2014, a total of 270 patients received endovascular treatment with stent retrievers (with or without intravenous thrombolysis). Significantly, more patients in the endovascular treatment group than in the intravenous thrombolysis group had a good outcome (37% vs. 27%, p < 0.01). The infarct sizes were significantly smaller after endovascular treatment than intravenous thrombolysis, whereas the symptomatic intracranial hemorrhages rates and in-hospital mortality were comparable between both treatment groups. The positive impact of endovascular treatment on clinical outcome was most pronounced in patients ≥75 years (31% endovascular treatment vs. 19% intravenous thrombolysis, p < 0.01), in patients with M1 occlusions (43% endovascular treatment vs. 25% intravenous thrombolysis, p < 0.01) and in patients with an admission National Institutes of Health Stroke Scale ≥ 14 (24% endovascular treatment vs. 11% intravenous thrombolysis, p < 0.05). CONCLUSION: In everyday clinical practice and compared with intravenous thrombolysis, endovascular treatment significantly improved clinical outcome and was associated with smaller infarctions. This beneficial effect appeared to be highest in older patients, more severely affected patients, and in those with M1 occlusions.

A laboratory model to evaluate cutout resistance of implants for pertrochanteric fracture fixation.

OBJECTIVES: To establish a laboratory model of implant cutout, which can evaluate the effect of implant design on cutout resistance in a clinically realistic "worst case" scenario. SETTING: Orthopaedic biomechanics laboratory. DESIGN: Implant cutout was simulated in an unstable pertrochanteric fracture model, which accounted for dynamic loading, osteoporotic bone, and a defined implant offset. For model characterization, lag screw cutout was simulated in human cadaveric specimens and in polyurethane foam surrogates. Subsequently, foam surrogates were used to determine differences in cutout resistance between 2 common lag screws (dynamic hip screw, Gamma) and 2 novel blade-type implant designs (dynamic helical hip system, trochanteric fixation nail). MAIN OUTCOME MEASURES: Implant migration was continuously recorded with a spatial motion tracking system as a function of the applied loading cycles. In addition, the total number of loading cycles to cutout failure was determined for specific load amplitudes. RESULTS: Implant migration in polyurethane surrogates closely correlated with that in cadaveric specimens, but yielded higher reproducibility and consistent cutout failure. The cutout model was able to delineate significant differences in cutout resistance between specific implant designs. At any of 4 load amplitudes (0.8 kN, 1.0 kN, 1.2 kN, 1.4 kN) dynamic hip screw lag screws failed earliest. The gamma nail lag screw could sustain significantly more loading cycles than the dynamic hip screw. Of all implants, trochanteric fixation nail implants demonstrated the highest cutout resistance. CONCLUSIONS: Implant design can significantly affect the fixation strength and cutout resistance of implants for pertrochanteric fracture fixation. The novel cutout model can predict differences in cutout resistance between distinct implant designs.

Role of the coracoacromial ligament as restraint after shoulder hemiarthroplasty.

Patients with an irreparable rotator cuff tear and glenohumeral degeneration often are treated with hemiarthroplasty. This procedure has proven effective as long as the coracoacromial ligament remained intact. The ligament reportedly acts as a restraint against anterosuperior dislocation. The purpose of the current study was to test the role of the coracoacromial ligament as an anterosuperior restraint after hemiarthroplasty in shoulders from cadavers with simulated irreparable rotator cuff tears. Six fresh-frozen shoulders were dissected to mimic a massive rotator cuff tear. After a hemiarthroplasty was done, each shoulder was mounted in a fixture, which was attached to a materials testing device. Using this device, the role of the coracoacromial ligament was evaluated by loading the shoulders in various positions and then measuring displacement before and after excision of the ligament. The mean difference in anterosuperior displacement was 3.44 mm. In all shoulders, subjective observation revealed that the humeral head often becomes wedged between the coracoid and the acromion during axial loading after excision of the coracoacromial ligament. Therefore, the coracoacromial ligament should be preserved to enhance the stability of the joint and to preserve the superior fulcrum.