Colonization and spreading dynamics of Lactiplantibacillus plantarum spoilage isolates on wet surfaces.

The role of lactic acid bacteria, including Lactiplantibacillus plantarum, in food spoilage is well recognized, while the behavior of these non-motile bacteria on wet surfaces, such as those encountered in food processing environments has gained relatively little attention. Here, we observed a fast colony spreading of non-motile L. plantarum spoilage isolates on wet surfaces via passive sliding using solid BHI agar media as a model. We investigated the effect of physical properties of agar hydrogel substrate on the surface spreading of six L. plantarum food isolates FBR1-6 and a model strain WCFS1, using increasing concentrations of agar from 0.25 up to 1.5% (w/v). Our results revealed that L. plantarum strain FBR2 spreads significantly on low agar concentration plates compared to the other strains studied here (with a factor of 50-60 folds higher surface coverage), due to the formation of very soft biofilms with high water content that can float on the surface. The fast-spreading of FBR2 colonies is accompanied by an increased number of cells, elongated cell morphology, and a higher amount of extracellular components. Our finding highlights colonization dynamics and the spreading capacity of non-motile bacteria on surfaces that are relatively wet, thereby revealing an additional hitherto unnoticed parameter for non-motile bacteria that may contribute to contamination of foods by fast surface spreading of these bacteria in food processing environments.

Lactobacillus plantarum strains show diversity in biofilm formation under flow conditions.

In many natural and technological applications, microbial biofilms grow under fluid flow. In this project, we investigated the influence of flow on the formation and growth of biofilms produced by gram-positive Lactobacillus plantarum strains WCFS1 and CIP104448. We used an in-house designed device based on a 48-well plate with culture volumes of 0.8 ml, and quantified total biofilm formation under static and flow conditions with flow rates 0.8, 1.6, 3.2 and 4.8 ml/h (with 1, 2, 4 and 6 volume changes per hour) using crystal violet (CV) staining, and determined the number of viable biofilm cells based on plate counts. The amount of total biofilm under flow conditions increased in the CIP 104448 strain, with significantly increased staining at the wall of the wells. However, in the WCFS1 strain, no significant difference in the amount of biofilm formed under flow and static conditions was observed. Plate counts showed that flow caused an increase in the number of viable biofilm cells for both strains. In addition, using enzyme treatment experiments, we found that for WCFS1 in the static condition, the amount of mature biofilm was declined after DNase I and Proteinase K treatment, while for flow conditions, the decline was only observed for DNase I treatment. The CIP104448 biofilms formed under both static and flow conditions only showed a decline in the CV staining after adding Proteinase K, indicating different contributions of extracellular DNA (eDNA) and proteinaceous matrix components to biofilm formation in the tested strains.

Strong future increases in Arctic precipitation variability linked to poleward moisture transport.

The Arctic region is projected to experience amplified warming as well as strongly increasing precipitation rates. Equally important to trends in the mean climate are changes in interannual variability, but changes in precipitation fluctuations are highly uncertain and the associated processes are unknown. Here, we use various state-of-the-art global climate model simulations to show that interannual variability of Arctic precipitation will likely increase markedly (up to 40% over the 21st century), especially in summer. This can be attributed to increased poleward atmospheric moisture transport variability associated with enhanced moisture content, possibly modulated by atmospheric dynamics. Because both the means and variability of Arctic precipitation will increase, years/seasons with excessive precipitation will occur more often, as will the associated impacts.

Rapid Spreading of a Droplet on a Thin Soap Film.

We study the spreading of a droplet of surfactant solution on a thin suspended soap film as a function of dynamic surface tension and volume of the droplet. Radial growth of the leading edge (R) shows power-law dependence on time with exponents ranging roughly from 0.1 to 1 for different surface tension differences (Δσ) between the film and the droplet. When the surface tension of the droplet is lower than the surface tension of the film (Δσ > 0), we observe rapid spreading of the droplet with R ≈ tα, where α (0.4 < α < 1) is highly dependent on Δσ. Balance arguments assuming the spreading process is driven by Marangoni stresses versus inertial stresses yield α = 2/3. When the surface tension difference does not favor spreading (Δσ < 0), spreading still occurs but is slow with 0.1 < α < 0.2. This phenomenon could be used for stretching droplets in 2D and modifying thin suspended films.

Foam and thin films of hydrophilic silica particles modified by ß-casein.

HYPOTHESIS: Foaming properties of particle dispersions can be modified by addition of amphiphiles. The molar ratio between particles and amphiphiles will influence the wetting properties of the particles as well as the bulk concentration of the amphiphiles. This will have an effect on air/water interfacial composition as well as on the thin film and foam stability of the mixed system. EXPERIMENTS: In this research foams and thin films of hydrophilic silica particles in presence of ß-casein (ß-CN) were investigated with different particle sizes and varying ß-CN/silica weight ratios (between 1:10 and 1:100). Samples were characterized for particles size, morphology as well as contact angle and related to their foaming, interfacial, and thin film properties. FINDINGS: A threshold weight ratio of ß-CN/silica was found to be 1:50 for foam stabilization with mixtures containing silica particles no larger than 1 µm and 1:30 for film stabilization with mixtures containing larger particles. At the interface, the modified silica particles were rather diluted without much interaction for surface compressions up to 30%. Large silica particles (0.0015% ß-CN, Csilica ≤ 0.15%) were dragged to the periphery of the thin liquid films but no decrease of the inner film draining rate by a decrease of capilary pressure gradient across the film was observed. The depletion of ß-casein in the bulk by particles played a major role in foam destabilization.

[A toddler with a mandibular fracture]. / Een peuter met een mandibulafractuur.

BACKGROUND: Mandibular fractures are rare in children. Symptoms of these fractures include preauricular pain and swelling, trismus and pain when opening the mouth, and they are often preceded by a fall on the chin. If the diagnosis is missed they may have serious consequences for the growth and development of the jaw. CASE DESCRIPTION: A 3-year-old boy was referred with a swelling in his left cheek, fever and vomiting. Two days earlier he had fallen on his chin. At physical examination he had severe preauricular pain on palpation and a trismus. The patient was admitted because of suspicion of a viral parotitis and the threat of dehydration. After discharge, he went to the dentist for examination of a molar that was painful to the touch. The dentist performed an orthopantomogram and discovered a fracture of the left mandibular collum. CONCLUSION: Any child with trauma to the chin should be observed for symptoms of a mandibular fracture, and if it seems necessary non-invasive radiographic examination should be performed.

Structure engineering of filled protein microbeads to tailor release of oil droplets in gastric digestion.

Oil-soluble components can be encapsulated in an O/W1/W2 microsystem, in which they are dissolved in oil droplets dispersed in a gelled microbead (W1), which forms a barrier between the oil droplets and the aqueous continuous phase (W2). We investigated the rate and mechanism of breakdown of protein microbeads in a simulated gastric system, and studied the influence of microbead protein concentration, gelling method (cold-set, slow and fast heat-set), and further processing (freeze-drying), on the breakdown process. Breakdown rate decreased with increasing protein content of the beads, for the same method of production. Due to the porosity of the slowly-heated heat-set beads, breakdown occurred evenly throughout the entire bead. Cold-set microbeads of 10% protein broke down slightly slower than the heat-set microbeads of 15%. The denser surface of the 10% beads slowed down the diffusion of the enzymes into the bead's interior, causing the beads to be broken down from the outside inward. All these beads broke down within one hour. Increasing the rate of temperature increase during the heating step dramatically slowed breakdown. There was no significant breakdown of rapidly heated beads within 138 minutes, even though no difference in microstructure between rapidly and slowly heated beads was visible with electron microscopy. Freeze-drying of the beads also slowed their breakdown. After 132 minutes more than half the measured particle volume of were intact beads. Freeze-drying changed the microstructure of the beads irreversibly: rehydrating the dried beads did not result in a breakdown behaviour similar to that of unprocessed beads.

Safety and long-term effects of renal denervation: Rationale and design of the Dutch registry.

BACKGROUND: Percutaneous renal denervation (RDN) has recently been introduced as a treatment for therapy-resistant hypertension. Also, it has been suggested that RDN may be beneficial for other conditions characterised by increased sympathetic nerve activity. There are still many uncertainties with regard to efficacy, safety, predictors for success and long-term effects. To answer these important questions, we initiated a Dutch RDN registry aiming to collect data from all RDN procedures performed in the Netherlands. METHODS: The Dutch RDN registry is an ongoing investigator-initiated, prospective, multicentre cohort study. Twenty-six Dutch hospitals agreed to participate in this registry. All patients who undergo RDN, regardless of the clinical indication or device that is used, will be included. Data are currently being collected on eligibility and screening, treatment and follow-up. RESULTS: Procedures have been performed since August 2010. At present, data from 306 patients have been entered into the database. The main indication for RDN was hypertension (n = 302, 99%). Patients had a mean office blood pressure of 177/100 (±29/16) mmHg with a median use of three (range 0-8) blood pressure lowering drugs. Mean 24-hour blood pressure before RDN was 157/93 (±18/13) mmHg. RDN was performed with different devices, with the Simplicity™ catheter currently used most frequently. CONCLUSION: Here we report on the rationale and design of the Dutch RDN registry. Enrolment in this investigator-initiated study is ongoing. We present baseline characteristics of the first 306 participants.

Perinatal outcomes after hypertensive disorders in pregnancy in a low resource setting.

OBJECTIVE: The objective of this study was to evaluate perinatal outcomes of pregnancies complicated by hypertensive disorders in pregnancy in an urban sub-Saharan African setting. METHODS: A prospective cohort study of 1010 women of less than 17 weeks of gestation was conducted at two antenatal clinics in Accra, Ghana, between July 2012 and March 2014. Information about hypertensive disorders was available for analysis on 789 pregnancies. The main outcomes were pre-term birth, birthweight, Apgar scores, small for gestational age and mortality. Relative risk (RR, 95% confidence interval (CI)) for the association between hypertensive disorders of pregnancy and perinatal outcomes was assessed using logistic regression adjusting for potential confounders. RESULTS: A total of 88.7% of women remained normotensive, 7.5% developed pregnancy-induced hypertension, 2.0% had chronic hypertension, and 1.7% developed (pre-)eclampsia. No adverse effects were observed in women with pregnancy-induced hypertension. Women with chronic hypertension were more likely to have a lower gestational age at delivery (38.0 ± 2.3 weeks vs. 39.0 ± 1.9 weeks, P = 0.04) and higher risk of pre-term delivery (aRR 4.63, 95% CI 1.35-15.91). Women with pre-eclampsia had emergency Caesarean section significantly more often (88.9% vs. 50%, P = 0.04), with a higher risk for low birthweight infants (aRR 7.95, 95% CI 1.41-44.80) and a higher risk of neonatal death (aRR 18.41, 95% CI 1.20-283.22). CONCLUSION: Comparable to high-income countries, in Accra hypertensive disorders during pregnancy were associated with increased risk of adverse perinatal outcomes necessitating maternal and newborn care.

Protein Aggregates May Differ in Water Entrapment but Are Comparable in Water Confinement.

Aggregate size and density are related to gel morphology. In the context of the water distribution in complex food systems, in this study, it was aimed to investigate whether protein aggregates varying in size and density differ in entrapped and confined water. Heat-set soy protein aggregates (1%, v/v) prepared in the presence of 3.5 mM divalent salts increased in size and decreased in apparent density following the salt type order MgSO4, MgCl2, CaSO4, and CaCl2. In the absence of applied (centrifugal) forces, larger and less dense aggregates entrap more water. When force is applied from larger and more deformable aggregates, more water can be displaced. Entrapped water of ∼8-13 g of water/g of protein is associated with (pelleted) aggregates, of which approximately 4.5-8.5 g of water/g of protein is not constrained in exchangeability with the solvent. The amount of confined water within aggregates was found to be independent of the aggregate density and accounted for ∼3.5 g of water/g of protein. Confined water in aggregates is hindered in its diffusion because of physical structure constraints and, therefore, not directly exchangeable with the solvent. These insights in the protein aggregate size and deformability in relation to water entrapment and confinement could be used to tune water holding on larger length scales when force is applied.

Determining scaphoid waist fracture union by conventional radiographic examination: an analysis of reliability and validity.

INTRODUCTION: Conventional radiographic imaging is the first imaging tool of choice in scaphoid fractures. The majority of undisplaced scaphoid waist fractures unite after 6 weeks of cast immobilization. We hypothesized that conventional radiographic imaging at 6 weeks after injury can both accurately and reliably predict union in undisplaced scaphoid waist fractures. MATERIALS AND METHODS: Fleiss' kappa statistics were used concerning the opinions of four observers reviewing 47 sets of good-quality scaphoid radiographs of undisplaced scaphoid waist fractures. As reference standard for union, radiographs were taken at a minimum of 6 months after injury to determine validity. RESULTS: Overall agreement was defined as moderate. (κ = 0.583) "No consolidation" (κ = 0.816), "full consolidation" (κ = 0.517) and "partial consolidation" (κ = 0.390) were defined as good, moderate and fair agreement, respectively. The average sensitivity and specificity of diagnosing scaphoid waist fracture union on standard scaphoid radiographs were 0.65 and 0.67, respectively. The positive predictive value for diagnosing union was 0.93 and the negative predictive value was 0.22. CONCLUSIONS: Conventional radiographic imaging is accurate and moderately reliable in diagnosing union, and reliable but inaccurate in diagnosing nonunion of scaphoid waist fractures at 6 weeks follow-up.

Thromboembolic complications after Zenith® Low Profile Endovascular Graft for infrarenal abdominal aneurysms.

PURPOSE: The purpose of this study was to objectify and evaluate risk factors for thromboembolic complications after treatment with a Zenith(®) Low Profile Endovascular Graft (Zenith LP). Results were compared with those in the recent literature on endovascular aortic repair (EVAR) and with the thromboembolic complications in the patient group treated with a Zenith Flex Endovascular Graft in our institute in the period before the use of the Zenith LP. MATERIALS AND METHODS: All consecutive patients who were suitable for treatment with a Zenith LP endograft between October 2010 and December 2011 were included. The preprocedural computed tomography scan (CT), procedural angiographic images, and the postprocedural CT scans were evaluated for risk factors for and signs of thromboembolic complications. All patients treated between December 2007 and November 2012 with a Zenith Flex endograft were retrospectively evaluated for thromboembolic complications. RESULTS: In the study period 17 patients were treated with a LP Zenith endograft. Limb occlusion occurred in 35 % of the patients. Limb occlusions occurred in 24 % of the limbs at risk (one limb occluded twice). In one patient two risk factors for limb occlusion were identified. Between December 2007 and November 2012, a total of 43 patients were treated with a Zenith Flex endograft. No limb occlusion or distal embolization occurred. CONCLUSION: Despite that this was a small retrospective study, the Zenith LP endograft seems to be associated with more frequent thromboembolic complications compared with the known limb occlusion rates in the literature and those of the patients treated with a Zenith Flex endograft in our institute.

Origin of water loss from soy protein gels.

Water holding (WH) of soy protein gels was investigated to identify which length scales are most contributing to WH when centrifugal forces are applied. More specifically, it was attempted to differentiate between the contributions of submicron and supramicron length scales. MgSO4 and MgCl2 salt specificities on soy protein aggregation (submicron contribution) were used to create different gel morphologies (supramicron contribution). Obtained results showed that the micrometer length scale is the most important contribution to WH of gels under the applied deformation forces. WH of soy protein gels correlated negatively with Young's modulus and positively with recoverable energy. The occurrence of rupture events had only a limited impact on WH. The ease by which water may be removed from the gel, but not the total amount, seemed to be related to the initial building block size. These insights could be exploited in product development to predict and tune oral perception properties of (new) products.

High amounts of broccoli in pasta-like products: nutritional evaluation and sensory acceptability.

Pasta and noodles were enriched with concentrations of broccoli powder (BP) up to 30% (v/v). To ensure the benefits from the broccoli nutrients, their leakage during cooking should be prevented. Such leakage is determined by the microstructure. In a previous study we have shown that the microstructure can change dramatically in such broccoli-enriched products. In this article we investigated the amount of nutrients retained within the product. As a representative of nutrients we have chosen glucosinolates (GLs). Therefore, we have investigated the concentration of these phytochemicals in dried and cooked pasta and noodles. We have found that glucosinolates present in the pasta and noodles increase linearly with the volume fraction of BP up to 20%. At 30% BP the retained amount of GLs was equal to that of 20% BP and did not increase further. Therefore incorporation of 30% BP does not lead to additional health benefits over incorporation of 20% BP. We conclude that the nutritional function of our pasta-like products can be improved by enrichment up to 20% broccoli. This value is much higher than that found in common commercial products (which is a few percent). In this article we also briefly address the sensory acceptability of such products. Up to 20% broccoli the products turned out to remain acceptable. Combining this with our results on texture analysis we conclude that the GLs release, sensory acceptability and textural properties are related via the microstructure.

The changing seasonal climate in the Arctic.

Ongoing and projected greenhouse warming clearly manifests itself in the Arctic regions, which warm faster than any other part of the world. One of the key features of amplified Arctic warming concerns Arctic winter warming (AWW), which exceeds summer warming by at least a factor of 4. Here we use observation-driven reanalyses and state-of-the-art climate models in a variety of standardised climate change simulations to show that AWW is strongly linked to winter sea ice retreat through the associated release of surplus ocean heat gained in summer through the ice-albedo feedback (~25%), and to infrared radiation feedbacks (~75%). Arctic summer warming is surprisingly modest, even after summer sea ice has completely disappeared. Quantifying the seasonally varying changes in Arctic temperature and sea ice and the associated feedbacks helps to more accurately quantify the likelihood of Arctic's climate changes, and to assess their impact on local ecosystems and socio-economic activities.

Genome-wide expression analysis of paired diagnosis-relapse samples in ALL indicates involvement of pathways related to DNA replication, cell cycle and DNA repair, independent of immune phenotype.

Almost a quarter of pediatric patients with acute lymphoblastic leukemia (ALL) suffer from relapses. The biological mechanisms underlying therapy response and development of relapses have remained unclear. In an attempt to better understand this phenomenon, we have analyzed 41 matched diagnosis-relapse pairs of ALL patients using genome-wide expression arrays (82 arrays) on purified leukemic cells. In roughly half of the patients, very few differences between diagnosis and relapse samples were found ('stable group'), suggesting that mostly extra-leukemic factors (for example, drug distribution, drug metabolism, compliance) contributed to the relapse. Therefore, we focused our further analysis on 20 sample pairs with clear differences in gene expression ('skewed group'), reasoning that these would allow us to better study the biological mechanisms underlying relapsed ALL. After finding the differences between diagnosis and relapse pairs in this group, we identified four major gene clusters corresponding to several pathways associated with changes in cell cycle, DNA replication, recombination and repair, as well as B-cell developmental genes. We also identified cancer genes commonly associated with colon carcinomas and ubiquitination to be upregulated in relapsed ALL. Thus, about half of the relapses are due to the selection or emergence of a clone with deregulated expression of genes involved in pathways that regulate B-cell signaling, development, cell cycle, cellular division and replication.

Endovascular treatment of traumatic ruptures of the thoracic aorta.

Rupture of the thoracic aorta after a blunt traumatic accident is a life-threatening event. This injury is instantly fatal in about 80% of the victims, and half of those who initially survive the incident will die during the first day, if left untreated. Before 1997, patients were treated with an open repair, but the conventional surgical approach carries a high mortality and morbidity rate. Graft interposition and cross-clamping of the aorta are responsible for a high paraplegia rate. Despite the fact that active distal perfusion of the aorta lowers the incidence of neurological deficit, the timing of these extensive procedures in the severely injured multi-trauma patient is difficult. The endovascular repair of a traumatic thoracic aortic rupture has gained rapid acceptance as a better alternative. This minimally invasive procedure has a median operating time of <1 h, and it can be done during the same session in which other life-threatening injuries are repaired. There is no need for a thoracotomy or single lung ventilation, blood loss is minimal and systemic heparinization is not required. So far, no spinal cord ischemia has been described for the endovascular repair. Besides numerous advantages, a few problems can be expected. The narrow aortic diameter of these young trauma-victims, combined with a steep aortic arch, makes the adaptation of the endograft along the inner curvature sometimes difficult. Because the smallest endograft usually exceeds the narrow aortic diameter, only excessively oversized devices can be used, which explains the high type I endoleak encountered in the published series. No randomized studies are yet available comparing the open with the endovascular technique, but the initial results of the endovascular repair seem promising and lower mortality and morbidity rates are documented. Long-term outcome are lacking so far, but are needed to address the durability of the procedure. Further research and development should concentrate on the problems we have seen with steep and narrow aortic arches, and devices with more flexible curves and smaller diameters should become available in the near future.

Micrometer-sized fibrillar protein aggregates from soy glycinin and soy protein isolate.

Long, fibrillar semiflexible aggregates were formed from soy glycinin and soy protein isolate (SPI) when heated at 85 degrees C and pH 2. Transmission electron microscopy analysis showed that the contour length of the fibrils was approximately 1 microm, the persistence length 2.3 microm, and the thickness a few nanometers. Fibrils formed from SPI were more branched than the fibrils of soy glycinin. Binding of the fluorescent dye Thioflavin T to the fibrils showed that beta-sheets were present in the fibrils. The presence of the fibrils resulted in an increase in viscosity and shear thinning behavior. Flow-induced birefringence measurements showed that the behavior of the fibrils under flow can be described by scaling relations derived for rodlike macromolecules. The fibril formation could be influenced by the protein concentration and heating time. Most properties of soy glycinin fibrils are comparable to beta-lactoglobulin fibrils.

Life-saving therapy for haemorrhaging liver adenomas using selective arterial embolization.

BACKGROUND: Emergency treatment for patients with a ruptured hepatocellular adenoma is controversial. The aim of this study was to evaluate management with selective arterial embolization. METHODS: The study included 11 consecutive patients treated for ruptured hepatocellular adenomas between 2001 and 2006. After initial haemodynamic support, all patients received selective embolization of branches of the hepatic artery. The primary outcome was effectiveness in stopping the bleeding. Secondary outcomes were complications and changes in tumour size after embolization. RESULTS: A single embolization brought haemorrhaging under control in ten patients; one patient needed three embolizations. None of the patients required emergency surgery. In the follow-up of 19 (range 7-49) months, no general or hepatobiliary complications were observed. All 25 adenomas, including those without signs of haemorrhaging in the same liver lobe, were either smaller or not detectable on computed tomography or magnetic resonance imaging after embolization, with the median diameter decreasing from 7.0 to 2.5 cm (P < 0.001). CONCLUSION: Selective embolization of the hepatic artery is a safe and adequate first approach in the management of patients with haemorrhaging hepatocellular adenomas. Furthermore, arterial embolization reduces the size of adenomas in the liver.

A novel technique for auxiliary partial liver transplantation with reno-portal anastomosis and avoidance of the hepatoduodenal ligament.

Auxiliary liver transplantation (ALT) is a treatment for acute liver failure when regeneration of the native liver is possible or for metabolic disorders. In selected cases ALT and orthotopic liver transplantation (OLT) have similar survival when ALT is performed in the orthotopic position (auxiliary partial orthotopic liver transplantation, APOLT). Drawback of ALT with portal vein to portal vein anastomosis is the frequent occurrence of thrombosis, compromising both graft and native liver, and the necessity of a significant resection. To avoid division of portal flow we performed ALT with an end-to-end anastomosis between the graft portal vein and the left renal vein of the recipient (reno-portal ALT, REPALT). The hepatic artery was anastomosed to the aorta using an iliac arterial graft conduit. The bile duct was anastomosed to the stomach. In the two cases presented here excellent immediate graft function occurred with rapid regeneration of the graft and without early vascular complications.