Antiscaling Pickering Emulsions Enabled by Amphiphilic Hairy Cellulose Nanocrystals.

Nucleation and growth of sparingly soluble salts, referred to as scaling, has posed substantial challenges in industrial processes that deal with multiphase flows, including enhanced oil recovery (EOR). During crude oil extraction/recovery, seawater is injected into oil reservoirs and yields water-in-oil (W/O) emulsions that may undergo calcium carbonate (CaCO3) scaling. Common antiscaling macromolecules and nanoparticles have adverse environmental impacts and/or are limited to functioning only in single-phase aqueous media. Here, we develop a novel antiscaling cellulose-based nanoparticle that enables scale-resistant Pickering emulsions. Cellulose fibrils are rationally nanoengineered to yield amphiphilic hairy cellulose nanocrystals (AmHCNC), bearing hydrophilic dicarboxylate groups and hydrophobic alkyl chains on disordered cellulose chains (hairs) protruding from nanocrystal ends. The unique chemical and structural properties of AmHCNC render them the first dual functional antiscaling and emulsion stabilizing nanoparticle. AmHCNC stabilize W/O Pickering emulsions at a concentration of 1.00 wt % for 1 week while inhibiting CaCO3 scale formation up to 70% by mass at a supersaturation degree of ∼101 compared with the synthetic surfactant Span 80. To the best of our knowledge, this study presents the first biopolymer-based solution for the long-lasting scaling challenge in multiphase media, which may set the stage for developing sustainable scale-resistant multiphase flows in a broad spectrum of industrial sectors.

Nanoengineering the Redispersibility of Cellulose Nanocrystals.

Enhancing the redispersibility of dried colloidal particles to yield stable dispersions after rehydration is a persistent challenge in the sustainable processing of nanocelluloses due to hydrogen bonding-induced irreversible aggregation. Programming nanocelluloses, such as cellulose nanocrystals (CNC), with moieties that enable colloidal repulsion after rehydration may address this challenge and contribute to the United Nation (UN)'s sustainable development goals (SDGs) of urban development and sustainable living (SDGs 9 and 11) and cradle-to-cradle processing (SDG 12). We hypothesize that imparting electrosteric repulsion to CNC via polyanionic disordered cellulose chains (hairs) protruding from each end may render the dried nanocrystals highly redispersible in aqueous media. Anionic hairy CNC (AHCNC), that is, CNC decorated with dicarboxylated cellulose (DCC) chains, were synthesized by the preferential, successive periodate/chlorite oxidation of the disordered regions of cellulose fibrils, bearing >5 mmol of carboxylate groups per gram. The colloidal properties of AHCNC were compared with those of sulfate half-ester group-functionalized CNC and TEMPO-oxidized CNC (TOCNC) after redispersion in aqueous media, followed by comparing the redispersibility of AHCNC and CNC in aqueous solutions containing monovalent or divalent cations and at varying pH. The AHCNC had remarkable aqueous redispersibility even at high ionic strengths and extreme pH. The unique redispersibility mechanism of dried AHCNC relies on the synergistic steric and electrostatic repulsion forces, recuperated upon the rehydration of DCC. This work may open new opportunities for more sustainable and cost-effective handling and processing of nanocelluloses.

Which pre-hospital triage parameters indicate a need for immediate evaluation and treatment of severely injured patients in the resuscitation area?

PURPOSE: To find ways to reduce the rate of over-triage without drastically increasing the rate of under-triage, we applied a current guideline and identified relevant pre-hospital triage predictors that indicate the need for immediate evaluation and treatment of severely injured patients in the resuscitation area. METHODS: Data for adult trauma patients admitted to our level-1 trauma centre in a one year period were collected. Outpatients were excluded. Correct triage for trauma team activation was identified for patients with an ISS or NISS ≥ 16 or the need for ICU treatment due to trauma sequelae. In this retrospective analysis, patients were assigned to trauma team activation according to the S3 guideline of the German Trauma Society. This assignment was compared to the actual need for activation as defined above. 13 potential predictors were retained. The relevance of the predictors was assessed and 14 models of interest were considered. The performance of these potential triage models to predict the need for trauma team activation was evaluated with leave-one-out cross-validated Brier and logarithmic scores. RESULTS: A total of 1934 inpatients ≥ 16 years were admitted to our trauma department (mean age 48 ± 22 years, 38% female). Sixty-nine per cent (n = 1341) were allocated to the emergency department and 31% (n = 593) were treated in the resuscitation room. The median ISS was 4 (IQR 7) points and the median NISS 4 (IQR 6) points. The mortality rate was 3.5% (n = 67) corresponding to a standardized mortality ratio of 0.73. Under-triage occurred in 1.3% (26/1934) and over-triage in 18% (349/1934). A model with eight predictors was finally selected with under-triage rate of 3.3% (63/1934) and over-triage rate of 10.8% (204/1934). CONCLUSION: The trauma team activation criteria could be reduced to eight predictors without losing its predictive performance. Non-relevant parameters such as EMS provider judgement, endotracheal intubation, suspected paralysis, the presence of burned body surface of > 20% and suspected fractures of two proximal long bones could be excluded for full trauma team activation. The fact that the emergency physicians did a better job in reducing under-triage compared to our final triage model suggests that other variables not present in the S3 guideline may be relevant for prediction.

Early computed tomography or focused assessment with sonography in abdominal trauma: what are the leading opinions?

PURPOSE: The initial assessment of severely injured patients in the resuscitation room requires a systematic and quickly performed survey. Whereas the Advanced Trauma Life Support (ATLS®)-based algorithm recommends focused assessment with sonography in trauma (FAST) among others, recent studies report a survival advantage of early whole-body computed tomography (WBCT) in haemodynamically stable as well as unstable patients. This study assessed the opinions of trauma surgeons about the early use of WBCT in severely injured patients with abdominal trauma, and abdominal CT in patients with isolated abdominal trauma, during resuscitation room treatment. METHODS: An online cross-sectional survey was performed over 8 months. Members of the Swiss Society for Surgery and the Austrian and German associations for trauma surgery were invited to answer nine online questions. RESULTS: Overall, 175 trauma surgeons from 155 departments participated. For haemodynamically stable patients, most considered FAST (77.6%) and early CT (82.3%) to be the ideal diagnostic tools. For haemodynamically unstable patients, 93.4% considered FAST to be mandatory. For CT imaging in unstable patients, 47.5% agreed with the use of CT, whereas 52.5% rated early CT as not essential. For unstable patients with pathological FAST and clinical signs, 86.8% agreed to proceed with immediate laparotomy. CONCLUSIONS: Most surgeons rely on early CT for haemodynamically stable patients with abdominal trauma, whereas FAST is performed with similar frequency and is prioritized in unstable patients. It seems that the results of recent studies supporting early WBCT have not yet found broad acceptance in the surgical community.

The impact of body mass index and gender on the development of infectious complications in polytrauma patients.

PURPOSE: The aim was to test the impact of body mass index (BMI) and gender on infectious complications after polytrauma. METHODS: A total of 651 patients were included in this retrospective study, with an Injury Severity Score (ISS) ≥16 and age ≥16 years. The sample was subdivided into three groups: BMI <25 kg/m(2), BMI 25-30 kg/m(2), and BMI >30 kg/m(2), and a female and a male group. Infectious complications were observed for 31 days after admission. Data are given as mean ± standard errors of the means. Analysis of variance, Kruskal-Wallis test, χ(2) tests, and Pearson's correlation were used for the analyses and the significance level was set at P < 0.05. RESULTS: The overall infection rates were 31.0 % in the BMI <25 kg/m(2) group, 29.0 % in the BMI 25-30 kg/m(2) group, and 24.5 % in the BMI >30 kg/m(2) group (P = 0.519). The female patients developed significantly fewer infectious complications than the male patients (26.8 vs. 73.2 %; P < 0.001). The incidence of death was significantly decreased according to the BMI group (8.8 vs. 7.2 vs. 1.5 %; P < 0.0001) and the female population had a significantly lower mortality rate (4.1 vs. 13.4 %; P < 0.0001). Pearson's correlations between the Abbreviated Injury Scale (AIS) score and the corresponding infectious foci were not significant. CONCLUSION: Higher BMI seems to be protective against polytrauma-associated death but not polytrauma-associated infections, and female gender protects against both polytrauma-associated infections and death. Understanding gender-specific immunomodulation could improve the outcome of polytrauma patients.

Predictive ability of the ISS, NISS, and APACHE II score for SIRS and sepsis in polytrauma patients.

PURPOSE: Systemic inflammatory response syndrome (SIRS) and sepsis as causes of multiple organ dysfunction syndrome (MODS) remain challenging to treat in polytrauma patients. In this study, the focus was set on widely used scoring systems to assess their diagnostic quality. METHODS: A total of 512 patients (mean age: 39.2 ± 16.2, range: 16-88 years) who had an Injury Severity Score (ISS) ≥17 were included in this retrospective study. The patients were subdivided into four groups: no SIRS, slight SIRS, severe SIRS, and sepsis. The ISS, New Injury Severity Score (NISS), Acute Physiology and Chronic Health Evaluation II (APACHE II) scores, and prothrombin time were collected at admission. The Kruskal-Wallis test and χ(2)-test, multinomial regression analysis, and kernel density estimates were performed. Receiver operating characteristic (ROC) analysis is reported as the area under the curve (AUC). Data were considered as significant if p < 0.05. RESULTS: All variables were significantly different in all groups (p < 0.001). The odds ratio increased with increasing SIRS severity for NISS (slight vs. no SIRS, 1.06, p = 0.07; severe vs. no SIRS, 1.07, p = 0.04; and sepsis vs. no SIRS, 1.11, p = 0.0028) and APACHE II score (slight vs. no SIRS, 0.97, p = 0.44; severe vs. no SIRS, 1.08, p = 0.02; and sepsis vs. no SIRS, 1.12, p = 0.0028). ROC analysis revealed that the NISS (slight vs. no SIRS, AUC 0.61; severe vs. no SIRS, AUC 0.67; and sepsis vs. no SIRS, AUC 0.77) and APACHE II score (slight vs. no SIRS, AUC 0.60; severe vs. no SIRS, AUC 0.74; and sepsis vs. no SIRS, AUC 0.82) had the best predictive ability for SIRS and sepsis. CONCLUSION: Quick assessment with the NISS or APACHE II score could preselect possible candidates for sepsis following polytrauma and provide guidance in trauma surgeons' decision-making.

[Influence of V.A.C.-therapy on cytokines and growth factors in traumatic wounds]. / Einfluss der V.A.C.-Therapie auf Zytokine und Wachstumsfaktoren in Traumatischen Wunden.

OBJECTIVE: Clinical observations have shown an accelerated wound healing in wounds of patients treated by Vacuum Assisted Closure (V.A.C.)-therapy. The mechanisms of improved wound healing on cellular level have been hitherto less investigated. In this study the levels of proinflammatory interleukins (IL-6, IL-8, IL-10) and growth factors (VEGF, FGF-2) in serum and wound were monitored. METHODS: The study included 21 patients with traumatic wounds that could not be closed during the first surgical intervention. The soft tissue defects (n = 21) were closed temporarily by Epigard. During the first second-look operation after 2.0 +/- 0.2 days in an average, Epigard was used for another 2.5 +/- 0.4 days as temporary soft tissue coverage in 13 patients (group A). In the remaining 8 patients the wound conditioning was done by V.A.C.(R) for 2.4 +/- 0.3 days (group B). A total of 428 samples of serum and wound fluid samples were collected during the first and second look operation. Levels of IL-6, IL-8, IL-10, VEGF and FGF were measured specific by ELISA. RESULTS: In all interleukins and growth factors there were significant lower serum level concentrations compared with those in wound fluids. During the first temporary dressing change after wound coverage with Epigard the wound samples showed the following levels [Mean (SEM)]: IL-6 49 816 (19 889) pg/ml, IL-8 54 (16) ng/ml, IL-10 314 (44) pg/ml, VEGF 4 746 (766) pg/ml, FGF-2 494 (89) pg/ml. During the second dressing changes we monitored the following levels in group A: IL-6 7 218 (2 542) pg/ml, IL-8 69 (27) ng/ml, IL-10 261 (58) pg/ml, VEGF 3 551 (661) pg/ml, FGF-2 355 (67) pg/ml. In group B the samples of the wound fluid showed the following results: IL-6 16 966 (4 124) pg/ml [p = 0.02], IL-8 223 (91) ng/ml [p = 0.03], IL-10 233 (76) pg/ml [p = 0.38], VEGF 7 490 (1 565) pg/ml [p = 0.01], FGF-2 352 (43) pg/ml [p = 0.48]. CONCLUSION: The increased local release of IL-6, IL-8 and VEGF in wounds after V.A.C.-therapy may be involved in the accumulation of neutrophil granulocytes and angiogenesis, which seams to play a crucial role for the accelerated granulation tissue formation after V.A.C.-therapy compared to wounds treated by Epigard.

[Entrapment of the anterior tibial artery in a distal tibial fracture after intramedullary nailing]. / Entrapment der A. tibialis anterior in einer distalen Tibiafraktur nach intramedullärer Nagelung.

We present a patient with a closed displaced distal tibia fracture with entrapment of the anterior tibial vessels in the fracture after tibial nailing. This complication was initially not recognised. After several debridements of the forefoot on the same side due to open metatarsal fractures and severe soft tissue injury, a free latissimus dorsi flap was used for covering the dorsum pedis. Preoperative angiography showed occlusion of the anterior tibial artery at the fracture line which was interpreted as a secondary occlusion due to an intima lesion of the vessel after injury. The entrapment in the fracture line was recognised intra-operatively during the preparation of the anterior tibial vessel.

Inhibition of caspase activity prevents CD95-mediated hepatic microvascular perfusion failure and restores Kupffer cell clearance capacity.

Using a murine model, we studied the effect of agonistic anti-CD95 antibodies (aCD95) on sinusoidal lining cells and a potential protection by caspase inhibition. C3H/HeN mice were intravenously administered aCD95 (10 microgram/mouse) or unspecific IgG (control) in the presence or absence of the caspase inhibitor z-VAD-fmk. Analysis of hepatic microcirculation using intravital fluorescence microscopy revealed severe (P<0.01) sinusoidal perfusion failure and reduced (P<0.05) phagocytic activity of Kupffer cells (KC) within 2 h. Transmission electron micrographs demonstrated loss of integrity of sinusoidal endothelial cells as early as 1 h after aCD95 application, whereas histological manifestation of hepatocellular apoptosis and hemorrhagic necrosis was most pronounced at 6 h. Blocking of caspase activity attenuated (P<0.01) both hepatic microvascular perfusion failure and KC dysfunction. Accordingly, full protection of the liver from apoptotic damage and intact microarchitecture was observed in histological sections after z-VAD-fmk treatment. Mortality rate was 40% 6 h after aCD95 administration, whereas all animals survived in the z-VAD-fmk group (P<0.05). The activation of caspases through CD95 may primarily lead to damage of sinusoidal endothelial cells and hepatic microvascular perfusion failure. Moreover, reduced phagocytic capacity of KC may contribute to accumulation of toxic metabolites released by dying cells at the local site of inflammation, further aggravating liver injury.