Temporary Kirschner Wire Ankle Transfixation and Delayed ORIF: A Staged Operative Treatment for Closed Ankle Fractures with Tibiotalar Dislocations and Soft-Tissue Damage

Abstract : Background and Purpose: : Immediate ORIF (open reduction and internal fixation) is the treatment of choice for displaced ankle fractures. However, definitive treatment may have to be delayed due to compromised soft tissues. The value of temporary Kirschner wire ankle transfixation with staged ORIF for closed displaced ankle fractures with tibiotalar dislocations was determined. Patients and Methods: : In this retrospective case series (1997-2001), 92 patients (mean age 54 years, range 20-86 years) who underwent a staged procedure for isolated and closed displaced ankle fractures with tibiotalar dislocations were studied. Patients were primarily treated by means of immediate closed reduction. For stable fractures and adequate soft tissues a split plaster cast was applied (n = 50). K-wire transfixation was performed for unstable fracture-dislocations and/or critical soft tissues (n = 42). All patients underwent delayed ORIF after recovery of the soft tissues. Results: : In the K-wire group (KWG), local complication rate was 7%. Mean operating time was 30 min (5-65 min). In the plaster cast group (PCG), local complication rate was 10% (p = 0.72, not significant). Three redislocated ankles (6%) had to be transfixed secondarily. A higher grade of soft-tissue injuries in the KWG (p < 0.05) resulted in a longer time interval between primary treatment and staged ORIF (7 vs. 5 days; p < 0.05) and a longer hospital stay (19 vs. 17 days; p < 0.05) for the KWG. Conclusion: : Temporary K-wire ankle transfixation is an effective method for initial treatment of closed displaced ankle fractures with tibiotalar dislocation, if ORIF has to be delayed and immobilization in a split plaster cast is not suitable. Retention is reliable with a low complication rat

Measurement of compartment pressure of the rectus sheath during intra-abdominal hypertension in rats

Objective: To investigate whether the compartment pressure of the rectus sheath (CPRS) reflects the intra-abdominal pressure (IAP) under various conditions of intra-abdominal hypertension (IAH). Design and setting: Prospective experimental study with in vivo pressure measurements at the Institute for Clinical and Experimental Surgery, University of Saarland. Animals: Sprague-Dawley rats. Interventions: Stepwise increase and decrease in IAP with continuous measurement of the correspondent CPRS. Measurements and results: Physiological IAP (2 mmHg) and CPRS (6 mmHg) showed astatistically significant difference. Stepwise elevation in IAP was associated with asimultaneous increase in CPRS. Accordingly, stepwise decompression of IAP resulted in astepwise decrease in CPRS. Under both conditions Bland-Altman analysis comparing IAP to correspondent CPRS showed avery good agreement for IAP at or above 12 mmHg. In addition, closure of the overlaying subcutaneous tissue and skin did not affect CPRS or its correlation with IAP. Conclusions: CPRS accurately reflects IAP for IAP of 12 mmHg or higher. Thus CPRS measurements may represent anovel approach for diagnosis and monitoring of IA

A randomized controlled trial

Objective We report on the effect of hemoadsorption therapy to reduce cytokines in septic patients with respiratory failure. Methods This was a randomized, controlled, open-label, multicenter trial. Mechanically ventilated patients with severe sepsis or septic shock and acute lung injury or acute respiratory distress syndrome were eligible for study inclusion. Patients were randomly assigned to either therapy with CytoSorb hemoperfusion for 6 hours per day for up to 7 consecutive days (treatment), or no hemoperfusion (control). Primary outcome was change in normalized IL-6-serum concentrations during study day 1 and 7. Results 97 of the 100 randomized patients were analyzed. We were not able to detect differences in systemic plasma IL-6 levels between the two groups (n = 75; p = 0.15). Significant IL-6 elimination, averaging between 5 and 18% per blood pass throughout the entire treatment period was recorded. In the unadjusted analysis, 60-day-mortality was significantly higher in the treatment group (44.7%) compared to the control group (26.0%; p = 0.039). The proportion of patients receiving renal replacement therapy at the time of enrollment was higher in the treatment group (31.9%) when compared to the control group (16.3%). After adjustment for patient morbidity and baseline imbalances, no association of hemoperfusion with mortality was found (p = 0.19). Conclusions In this patient population with predominantly septic shock and multiple organ failure, hemoadsorption removed IL-6 but this did not lead to lower plasma IL-6-levels. We did not detect statistically significant differences in the secondary outcomes multiple organ dysfunction score, ventilation time and time course of oxygenation

Enzyme Scaffolds with Hierarchically Defined Properties via 3D Jet Writing

The immobilization of enzymes into polymer hydrogels is a versatile approach to improve their stability and utility in biotechnological and biomedical applications. However, these systems typically show limited enzyme activity, due to unfavorable pore dimensions and low enzyme accessibility. Here, 3D jet writing of water‐based bioinks, which contain preloaded enzymes, is used to prepare hydrogel scaffolds with well‐defined, tessellated micropores. After 3D jet writing, the scaffolds are chemically modified via photopolymerization to ensure mechanical stability. Enzyme loading and activity in the hydrogel scaffolds is fully retained over 3 d. Important structural parameters of the scaffolds such as pore size, pore geometry, and wall diameter are controlled with micrometer resolution to avoid mass‐transport limitations. It is demonstrated that scaffold pore sizes between 120 µm and 1 mm can be created by 3D jet writing approaching the length scales of free diffusion in the hydrogels substrates and resulting in high levels of enzyme activity (21.2% activity relative to free enzyme). With further work, a broad range of applications for enzyme‐laden hydrogel scaffolds including diagnostics and enzymatic cascade reactions is anticipated.In this article, the development and application of a water‐based bioink with preloaded enzymes is described. With 3D jet writing, a hydrodynamic jetting system, freestanding 3D hydrogel frameworks with defined micropores are brightened. The enzyme‐loaded scaffolds show a high enzymatic activity and can be tested for industrial use in a continuous flow reactor over several days.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/162721/2/mabi202000154_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/162721/1/mabi202000154.pd

Microdialysis of the rectus abdominis muscle for early detection of impending abdominal compartment syndrome

Objective: To investigate whether microdialysis is capable of assessing metabolic derangements during intra-abdominal hypertension (IAH), and whether monitoring of the rectus abdominis muscle (RAM) by microdialysis represents areliable approach in the early detection of organ dysfunctions in abdominal compartment syndrome (ACS). Design: Prospective, randomized, controlled animal study. Setting: University animal research facility. Subjects: Fifteen isoflurane-anesthetized and mechanically ventilated Sprague-Dawley rats. Interventions: IAH of 20 mmHg was induced for 3 h and followed by decompression and reperfusion for another 3-h period (n = 10). Five sham-operated animals served as controls. Microdialysis was performed in the anterior gastric wall, liver, kidney, and RAM. The anterior cervical muscles served as distant reference. Glucose, lactate, pyruvate, and glycerol was analyzed throughout the 6-h experiment. Measurements and main results: Prolonged IAH induced significant cardiopulmonary dysfunction and persistent abdominal organ injury. Microdialysis revealed asignificant increase of lactate/pyruvate and glycerol in kidney, intestine and liver, indicating ischemia, energy failure, and cell membrane damage. In addition, at 3 h IAH glucose was significantly decreased in all organs studied. The distant reference did not show any alteration of lactate/pyruvate, glycerol, and glucose over the entire 6-h observation period. In contrast to the other organs, microdialysis of the RAM showed an early and more pronounced increase of lactate, lactate/pyruvate and glycerol already at 1 h IAH. It is noteworthy that lactate, glycerol, and glucose did not completely recover upon decompression of IAH. Conclusions: Our data suggest that continuous microdialysis in the RAM may represent apromising tool for early detecting IAH-induced metabolic derangement

Influence of Melt-Pool Stability in 3D Printing of NdFeB Magnets on Density and Magnetic Properties

The current work presents the results of an investigation focused on the influence of process parameters on the melt-track stability and its consequence to the sample density printed out of NdFeB powder. Commercially available powder of Nd7.5Pr0.7Fe75.4Co2.5B8.8Zr2.6Ti2.5 alloy was investigated at the angle of application in selective laser melting of permanent magnets. Using single track printing the stability of the melt pool was investigated under changing process parameters. The influence of changing laser power, scanning speed, and powder layer thickness on density, porosity structure, microstructure, phase composition, and magnetic properties were investigated. The results showed that energy density coupled with powder layer thickness plays a crucial role in melt-track stability. It was possible to manufacture magnets of both high relative density and high magnetic properties. Magnetization tests showed a significant correlation between the shape of the demagnetization curve and the layer height. While small layer heights are beneficial for sufficient magnetic properties, the remaining main parameters tend to affect the magnetic properties less. A quasi-linear correlation between the layer height and the magnetic properties remanence (Jr), coercivity (HcJ) and maximum energy product ((BH)max) was found

Trajectories and Drivers of Genome Evolution in Surface-Associated Marine Phaeobacter

The extent of genome divergence and the evolutionary events leading to speciation of marine bacteria have mostly been studied for (locally) abundant, free-living groups. The genus Phaeobacter is found on different marine surfaces, seems to occupy geographically disjunct habitats, and is involved in different biotic interactions, and was therefore targeted in the present study. The analysis of the chromosomes of 32 closely related but geographically spread Phaeobacter strains revealed an exceptionally large, highly syntenic core genome. The flexible gene pool is constantly but slightly expanding across all Phaeobacter lineages. The horizontally transferred genes mostly originated from bacteria of the Roseobacter group and horizontal transfer most likely was mediated by gene transfer agents. No evidence for geographic isolation and habitat specificity of the different phylogenomic Phaeobacter clades was detected based on the sources of isolation. In contrast, the functional gene repertoire and physiological traits of different phylogenomic Phaeobacter clades were sufficiently distinct to suggest an adaptation to an associated lifestyle with algae, to additional nutrient sources, or toxic heavy metals. Our study reveals that the evolutionary trajectories of surface-associated marine bacteria can differ significantly from free-living marine bacteria or marine generalists

Educational Gender Inequality in Sub-Saharan African: A Long-Term Perspective

To what extent did sub-Saharan Africa's twentieth century schooling revolution benefit boys and girls equally? Using census data and a cohort approach, we examine gender gaps in years of education over the twentieth century at world region, country and district levels. First, we find that compared to other developing regions, Africa had a small initial educational gender gap but subsequently made the least progress in closing the gap. Second, in most of the 21 African countries studied, gender gaps increased during most of the colonial era (ca. 1880–1960) and declined, albeit at different rates, after independence. At the world region and country level, the expansion of men's education was initially associated with a growing gender gap, and subsequently a decline, a pattern we refer to as “educational gender Kuznets curve.” Third, using data from six decadal cohorts across 1,177 birth districts, we explore subnational correlates of educational gender inequality. This confirms the inverse-U relationship between the gender gap and male education. We also find that districts with railroads, more urbanization and early twentieth century Christian missions witnessed lower attainment gaps. We find no evidence that cash crop cultivation, agricultural division of labor or family systems were linked to gender gaps

Pulsed pressure perturbations, an extra dimension in NMR spectroscopy of proteins

The introduction of multidimensional NMR spectroscopy was a breakthrough in biological NMR methodology because it allowed the unequivocal correlation of different spin states of the system. The introduction of large pressure perturbations in the corresponding radio frequency (RF) pulse sequences adds an extra structural dimension into these experiments. We have developed a microprocessor-controlled pressure jump unit that is able to introduce fast, strong pressure changes at any point in the pulse sequences. Repetitive pressure changes of 80 MPa in the sample tube are thus feasible in less than 30 ms. Two general forms of these experiments are proposed here, the pressure perturbation transient state spectroscopy (PPTSS) and the pressure perturbation state correlation spectroscopy (PPSCS). PPTSS can be used to measure the rate constants and the activation energies and activation volumes for the transition between different conformational states including the folded and unfolded state of proteins, for polymerization-depolymerization processes, and for ligand binding at atomic resolution. PPSCS spectroscopy correlates the NMR parameters of different pressure-induced states of the system, thus allowing the measurement of properties of a given pressure induced state such as a folding intermediate in a different state, for example, the folded state. Selected examples for PPTSS and PPSCS spectroscopy are presented in this Article.DFGBFSFC