The effect of surgical strategy in difficult cholecystectomy cases on postoperative complications outcome: a value-based healthcare comparative study.

BACKGROUND: In patients undergoing laparoscopic cholecystectomy (LC) for complicated biliary disease, complication rates increase up to 30%. The aim of this study is to assess the effect of differences in surgical strategy comparing outcome data of two large volume hospitals. METHODS: A prospective database was created for all the patients who underwent a LC in two large volume hospitals between January 2017 and December 2018. In cases of difficult cholecystectomy in clinic A, regular LC or conversion were surgical strategies. In clinic B, laparoscopic subtotal cholecystectomy was performed as an alternative in difficult cases. The difficulty of the cholecystectomy (score 1-4) and surgical strategy (regular LC, subtotal cholecystectomy, conversion) were scored. Postoperative complications, reinterventions, and ICU admission were assessed. For predicting adverse postoperative complication outcomes, uni- and multivariable analyses were used. RESULTS: A total of 2104 patients underwent a LC in the study period of which 974 were from clinic A and 1130 were from clinic B. In total, 368 procedures (17%) were scored as a difficult cholecystectomy. In clinic A, more conversions were performed (4.4%) compared to clinic B (1.0%; p < 0.001). In clinic B, more subtotal laparoscopic cholecystectomies were performed (1.8%) compared to clinic A (0%; p = < 0.001). Overall complication rate was 8.2% for clinic A and 10.2% for clinic B (p = 0.121). Postoperative complication rates per group for regular LC, conversion, and subtotal cholecystectomy in difficult cholecystectomies were 45 (15%), 12 (24%), and 7 (35%; p = 0.035), respectively. The strongest predictor for Clavien-Dindo grade 3-5 complication was subtotal cholecystectomy. CONCLUSION: Surgical strategy in case of a difficult cholecystectomy seems to have an important impact on postoperative complication outcome. The effect of a subtotal cholecystectomy on complications is of great concern.

Controlled release of chlorhexidine from a mesoporous silica-containing macroporous titanium dental implant prevents microbial biofilm formation.

Roughened surfaces are increasingly being used for dental implant applications as the enlarged contact area improves bone cell anchorage, thereby facilitating osseointegration. However, the additional surface area also entails a higher risk for the development of biofilm associated infections, an etiologic factor for many dental ailments, including peri-implantitis. To overcome this problem, we designed a dental implant composed of a porous titanium-silica (Ti/SiO2) composite material and containing an internal reservoir that can be loaded with antimicrobial compounds. The composite material consists of a sol-gel derived mesoporous SiO2 diffusion barrier integrated in a macroporous Ti load-bearing structure obtained by powder metallurgical processing. The antimicrobial compounds can diffuse through the porous implant walls, thereby reducing microbial biofilm formation on the implant surface. A continuous release of µM concentrations of chlorhexidine through the Ti/SiO2 composite material was measured, without initial burst effect, over at least 10 days and using a 5 mM chlorhexidine solution in the implant reservoir. Metabolic staining, CFU counting and visualisation by scanning electron microscopy confirmed that Streptococcus mutans biofilm formation on the implant surface was almost completely prevented due to chlorhexidine release (preventive setup). Moreover, we demonstrated efficacy of released chlorhexidine against mature Streptococcus mutans biofilms (curative setup). In conclusion, we provide a proof of concept of the sustained release of chlorhexidine, one of the most widely used oral antiseptics, through the Ti/SiO2 material thereby preventing and eradicating biofilm formation on the surface of the dental implant. In principle, our flexible design allows for the use of any bioactive compound, as discussed.

Identification of new TRIP12 variants and detailed clinical evaluation of individuals with non-syndromic intellectual disability with or without autism.

The ubiquitin pathway is an enzymatic cascade including activating E1, conjugating E2, and ligating E3 enzymes, which governs protein degradation and sorting. It is crucial for many physiological processes. Compromised function of members of the ubiquitin pathway leads to a wide range of human diseases, such as cancer, neurodegenerative diseases, and neurodevelopmental disorders. Mutations in the thyroid hormone receptor interactor 12 (TRIP12) gene (OMIM 604506), which encodes an E3 ligase in the ubiquitin pathway, have been associated with autism spectrum disorder (ASD). In addition to autistic features, TRIP12 mutation carriers showed intellectual disability (ID). More recently, TRIP12 was postulated as a novel candidate gene for intellectual disability in a meta-analysis of published ID cohorts. However, detailed clinical information characterizing the phenotype of these individuals was not provided. In this study, we present seven novel individuals with private TRIP12 mutations including two splice site mutations, one nonsense mutation, three missense mutations, and one translocation case with a breakpoint in intron 1 of the TRIP12 gene and clinically review four previously published cases. The TRIP12 mutation-positive individuals presented with mild to moderate ID (10/11) or learning disability [intelligence quotient (IQ) 76 in one individual], ASD (8/11) and some of them with unspecific craniofacial dysmorphism and other anomalies. In this study, we provide detailed clinical information of 11 TRIP12 mutation-positive individuals and thereby expand the clinical spectrum of the TRIP12 gene in non-syndromic intellectual disability with or without ASD.

Short-term health effects in the general population following a major train accident with acrylonitrile in Belgium.

BACKGROUND: Following a train derailment, several tons of acrylonitrile (ACN) exploded, inflamed and part of the ACN ended up in the sewage system of the village of Wetteren. More than 2000 residents living in the close vicinity of the accident and along the sewage system were evacuated. A human biomonitoring study of the adduct N-2-cyanoethylvaline (CEV) was carried out days 14-21 after the accident. OBJECTIVES: (1) To describe the short-term health effects that were reported by the evacuated residents following the train accident, and (2) to explore the association between the CEV concentrations, extrapolated at the time of the accident, and the self-reported short-term health effects. METHODS: Short-term health effects were reported in a questionnaire (n=191). An omnibus test of independence was used to investigate the association between the CEV concentrations and the symptoms. Dose-response relationships were quantified by Generalized Additive Models (GAMs). RESULTS: The most frequently reported symptoms were local symptoms of irritation. In non-smokers, dose-dependency was observed between the CEV levels and the self-reporting of irritation (p=0.007) and nausea (p=0.007). Almost all non-smokers with CEV concentrations above 100pmol/g globin reported irritation symptoms. Both absence and presence of symptoms was reported by non-smokers with CEV concentrations below the reference value and up to 10 times the reference value. Residents who visited the emergency services reported more symptoms. This trend was seen for the whole range of CEV concentrations, and thus independently of the dose. DISCUSSION AND CONCLUSION: The present study is one of the first to relate exposure levels to a chemical released during a chemical incident to short-term (self-reported) health effects. A dose-response relation was observed between the CEV concentrations and the reporting of short-term health effects in the non-smokers. Overall, the value of self-reported symptoms to assess exposure showed to be limited. The results of this study confirm that a critical view should be taken when considering self-reported health complaints and that ideally biomarkers are monitored to allow an objective assessment of exposure.

Development and validation of an ultra-high performance liquid chromatography-tandem mass spectrometry method to measure creatinine in human urine.

Despite decades of creatinine measurement in biological fluids using a large variety of analytical methods, an accurate determination of this compound remains challenging. Especially with the novel trend to assess biomarkers on large sample sets preserved in biobanks, a simple and fast method that could cope with both a high sample throughput and a low volume of sample is still of interest. In answer to these challenges, a fast and accurate ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed to measure creatinine in small volumes of human urine. In this method, urine samples are simply diluted with a basic mobile phase and injected directly under positive electrospray ionization (ESI) conditions, without further purification steps. The combination of an important diluting factor (10(4) times) due to the use of a very sensitive triple quadrupole mass spectrometer (XEVO TQ) and the addition of creatinine-d3 as internal standard completely eliminates matrix effects coming from the urine. The method was validated in-house in 2012 according to the EMA guideline on bioanalytical method validation using Certified Reference samples from the German External Quality Assessment Scheme (G-Equas) proficiency test. All obtained results for accuracy and recovery are within the authorized tolerance ranges defined by G-Equas. The method is linear between 0 and 5 g/L, with LOD and LOQ of 5 × 10(-3) g/L and 10(-2) g/L, respectively. The repeatability (CV(r) = 1.03-2.07%) and intra-laboratory reproducibility (CV(RW) = 1.97-2.40%) satisfy the EMA 2012 guideline. The validated method was firstly applied to perform the German G-Equas proficiency test rounds 51 and 53, in 2013 and 2014, respectively. The obtained results were again all within the accepted tolerance ranges and very close to the reference values defined by the organizers of the proficiency test scheme, demonstrating an excellent accuracy of the developed method. The method was finally applied to measure the creatinine concentration in 210 urine samples, coming from 190 patients with a chronic kidney disease (CKD) and 20 healthy subjects. The obtained creatinine concentrations (ranging from 0.12 g/L up to 3.84 g/L) were compared, by means of a Passing Bablok regression, with the creatinine contents obtained for the same samples measured using a traditional compensated Jaffé method. The UHPLC-MS/MS method described in this paper can be used to normalize the concentration of biomarkers in urine for the extent of dilution.

Acrylonitrile exposure in the general population following a major train accident in Belgium: a human biomonitoring study.

BACKGROUND: On Saturday May 4, 2013, a train transporting chemicals derailed in the village of Wetteren (Belgium) and caused a leak of acrylonitrile (ACN). OBJECTIVES: To assess the human exposure to acrylonitrile in the local population with the highest suspected exposure. METHODS: Between May 18-25, 242 residents participated in the study. N-2-cyanoethylvaline (CEV), a biomarker that is highly specific for ACN exposure, was measured in the blood. To account for potential influence by smoking, cotinine was determined in the urine. Participants also filled in a short questionnaire. RESULTS: In the evacuated zone, 37.3% of the non-smokers and 40.0% of the smokers had CEV concentrations above the reference values of 10 and 200 pmol/g globin, respectively, at the time of the train accident. Spatial mapping of the CEV concentrations depending on the residential address showed a distribution pattern following the sewage system. DISCUSSION AND CONCLUSION: The train derailment resulted in a highly atypical sequence-of-events. In addition to exposure in the direct vicinity of the site of the train derailment, exposure also occurred via the sewage system, into which acrylonitrile had entered shortly after the accident.

Acrylonitrile exposure assessment in the emergency responders of a major train accident in Belgium: a human biomonitoring study.

BACKGROUND: On May 4, 2013, a train transporting chemicals derailed in Wetteren, Belgium. Several tanks loaded with acrylonitrile (ACN) exploded, resulting in a fire and a leakage of ACN. OBJECTIVES: To determine exposure to ACN and to assess discriminating factors for ACN exposure in the emergency responders involved in the on-site management of the train accident. METHODS: The study population consisted of 841 emergency responders. Between May 21 and June 28, they gave blood for the determination of N-2-cyanoethylvaline (CEV) hemoglobin adducts and urine for the measurement of cotinine. They also filled in a short questionnaire. RESULTS: 163 (26%) non-smokers and 55 (27%) smokers showed CEV concentrations above the reference values of 10 and 200 pmol/g globin, respectively. The 95th percentile in the non-smokers was 73 pmol/g globin and the maximum was 452 pmol/g globin. ACN exposure among the non-smokers was predicted by (1) the distance to the accident, (2) the duration of exposure, and (3) the occupational function. DISCUSSION AND CONCLUSION: Emergency responders involved in the on-site management of the train accident were clearly exposed to ACN from the accident. However, the extent of exposure remained relatively moderate with CEV concentrations staying within the ranges described in literature as background for a smoking population. Moreover, the exposure was less pronounced in the emergency responders as compared to that in the local population.

Update on Kleefstra Syndrome.

Kleefstra syndrome is characterized by the core phenotype of developmental delay/intellectual disability, (childhood) hypotonia and distinct facial features. The syndrome can be either caused by a microdeletion in chromosomal region 9q34.3 or by a mutation in the euchromatin histone methyltransferase 1 (EHMT1) gene. Since the early 1990s, 85 patients have been described, of which the majority had a 9q34.3 microdeletion (>85%). So far, no clear genotype-phenotype correlation could be observed by studying the clinical and molecular features of both 9q34.3 microdeletion patients and patients with an intragenic EHMT1 mutation. Thus, to further expand the genotypic and phenotypic knowledge about the syndrome, we here report 29 newly diagnosed patients, including 16 patients with a 9q34.3 microdeletion and 13 patients with an EHMT1 mutation, and review previous literature. The present findings are comparable to previous reports. In addition to our former findings and recommendations, we suggest cardiac screening during follow-up, because of the possible occurrence of cardiac arrhythmias. In addition, clinicians and caretakers should be aware of the regressive behavioral phenotype that might develop at adolescent/adult age and seems to have no clear neurological substrate, but is rather a so far unexplained neuropsychiatric feature.

Non-ideal behaviour of free vanadate on a Superose 12 size-exclusion column. Application to in vivo 48V-labelled rat spleen homogenate.

Seven chromatographic columns were evaluated for the recovery of 48V-radiolabelled vanadate. Further, the behaviour of vanadate (H2VO4-) was studied on a size-exclusion column Superose 12 as a function of (a) buffer salt molarity, (b) different buffer salts, (c) different buffers and (d) organic solvents added to the buffer. As opposed to the unsatisfactory recovery of V-compounds on other columns, we recovered the vanadium quantitatively. We observed that in most cases vanadate eluted after the total volume of the Superose 12 column. This indicates a non-ideal behaviour of vanadate. However, through this non-ideal behaviour it was possible to separate low-molecular-mass bound (Mr<5000) and unbound vanadium which would not be possible under normal behaviour. A possible explanation for this non-ideal behaviour of vanadium is put forward. The method has been successfully applied for the fractionation of different vanadium species in rat spleen homogenate.

In vivo distribution and speciation of [114mIn]InCl3 in the Wistar rat.

Five Wistar rats were given an intraperitoneal injection of [114mIn]InCl3 during four consecutive days. One hour after the last injection the rats were sacrificed. The in vivo distribution of 114mIn was studied in the blood and in different organs. Differential centrifugation was used to study the distribution in liver, kidney and spleen homogenate. Rat serum, packed cell lysate, urine and the cytosol of liver, kidney and spleen homogenate were examined by size exclusion fast protein liquid chromatography. The results showed that serum accounts for 90% of the indium activity in whole blood. Indium is preferentially accumulated within the liver, spleen and kidney, the highest amount of 114mIn being localised in the cytosolic fraction followed by the mitochondria. Size exclusion experiments showed that, in rat serum, indium is exclusively bound to transferrin. These results differed from earlier in vitro incubation experiments of human serum with 114mIn. It was not possible, from the experiments described herein, to conclude unequivocally whether indium is bound to haemoglobin of packed cell lysate or to another high molecular mass compound. Indium is associated with the high molecular mass fraction in liver, kidney and spleen cytosol; only in kidney are small amounts of 114mIn found in the low molecular mass fraction. The in vivo inhibitory effect of indium on the delta-aminolaevulinic acid dehydratase (ALAD) enzymatic activity in red blood cells and kidney tissue, well documented by other researchers, could not be attributed to direct binding of indium with this enzyme.

Effect of carbomer concentration and degree of neutralization on the mucoadhesive properties of polymer films.

Mucoadhesive drug delivery systems may enable a prolonged and localized drug release at various sites of the gastrointestinal tract. In the present study, the mucoadhesive properties of flexible polymeric films based on PVP or PVA as film-forming polymers were assessed by measuring the detachment force from excised porcine duodenal mucosa using a tensile strength tester. The mucoadhesive films were comprised of an impermeable backing layer of cellulose acetate butyrate. Carbopol 934P, Carbopol 974NF, and Noveon AA1 were incorporated as mucoadhesive excipients in concentrations of 0-22 wt% relative to the dry mass of the mucoadhesive layer and with various degrees of neutralization corresponding to pH 4.8, 5.5, 6.8, or 7.5. Films based on PVP were generally more mucoadhesive than corresponding formulations based on PVA. Maximum adhesion of PVP-films was observed at pH 5.5 and 6.8 depending on the type of the mucoadhesive polymer and its concentration. An optimal mucoadhesive polymer concentration range was found to be between 2 and 10 wt%. Higher polymer concentrations did not further enhance the mucoadhesive properties, and in some cases even decreased mucoadhesion. Film formulations based on PVA demonstrated no satisfactory mucoadhesive strength.

Study of the binding of 114mIn radiotracer to human serum components by ultrafiltration and chromatography.

The chemical speciation of indium in serum was studied. Ultrafiltration was used to investigate the influence of several buffer systems on the binding characteristics of indium in serum and to study the association of indium with transferrin and albumin. This was performed by means of batch incubation experiments with a 114mIn tracer. Different buffer systems were investigated. A series of bicarbonate, Tris:HCl and HEPES buffers were found to fit for this purpose. Phosphate buffer was not suitable, as it is capable of disrupting the binding between indium and transferrin. Batch ultrafiltration experiments with 114mIn incubated solutions of transferrin and albumin showed that both proteins are capable of binding indium to a high degree. Three chromatographic techniques (SEC, AEC, AC) were used to study the different chemically active species of indium in serum. It is concluded that next to transferrin, albumin is also responsible for the binding and transport of indium in serum.

Collagen microparticles: carriers for glucocorticosteroids.

Collagen microparticles were evaluated as a carrier system for glucocorticoids, and their physicochemical characteristics were determined. The particles were prepared by emulsifying and cross-linking native collagen. Particles in a size range of about 10 microns were obtained. The particle charge was dependent on the pH. A positive charge resulted when the surrounding medium had a pH below 4.5 and a negative charge with a pH above 4.5. This charge determined the magnitude of the interaction with dissolved charged drugs. The positively charged drug, prednylidene diethylaminoacetate, bound significantly to the particles above pH 4.5, whereas the negatively charged prednisolone sodium phosphate was bound below this pH. Adsorption of uncharged lipophilic drugs such as hydrocortisone was largely independent of the pH. The adsorption isotherm for this drug was determined and found to follow a Langmuir adsorption isotherm. The release and stability of the microparticle system was tested with hydrocortisone only, because of its pH-independent binding properties to the particles. The liberation of this drug was not influenced by the pH of the release medium. Binding to the particles did not effect the stability of hydrocortisone. The results of this study demonstrate that collagen microparticles can be successfully used as a carrier system for lipophilic steroids.

Intraneoplastic application of metrizamide-containing liposomes: kinetic studies with computed tomography.

Liposomes may serve as drug carriers not only for systemic chemotherapy but also for intraneoplastic drug therapy because they show a sustained drug release. In the present study, the in vivo kinetics of intraneoplastic deposits of large multilamellar vesicles containing metrizamide was followed up in a rat tumor model with computed tomography. The influence of four different lipid compositions on the retardation capacity of large multilamellar liposomes was investigated. By comparing the dynamic data of X-ray attenuation and volume of liposome deposits, a rank order for the in vivo stability of metrizamide containing multilamellar vesicles could be established: the least stable liposomes were made of pure dimyristoyl-phosphatidyl-choline, the most stable type was made of equimolar parts of stearoyl-palmitoyl-phosphatidyl-choline and cholesterol. Of intermediate stability were liposomes made of equimolar parts of dimyristoyl-phosphatidyl-choline and cholesterol, and those made of pure stearoyl-palmitoyl-phosphatidyl-choline. The addition of 50% cholesterol increased the membrane stability of both dimyristoyl-phosphatidyl-choline and stearoyl-palmitoyl-phosphatidyl-choline liposomes. No diffusion of large multilamellar liposomes away from the injection site was observed. The in vivo stability of the liposomes was considerably less than that observed in vitro, suggesting active degradation processes. It is concluded that large, multilamellar liposomes may be suitable carriers for intraneoplastic chemotherapy. The present model is easily adaptable to be transferred into clinical conditions, and may allow direct monitoring of intraneoplastic liposome-mediated chemotherapy in human brain tumors.

The effect of route of administration on the cimetidine-theophylline drug interaction.

The effect of route of cimetidine administration on cimetidine-mediated inhibition of theophylline oxidation was examined in healthy individuals. Based on the evidence that cimetidine-mediated inhibition of drug oxidation is competitive and, therefore, dependent on cimetidine concentration in the liver, oral cimetidine was tested to determine whether it would cause greater inhibition of drug oxidation than intravenous (IV) cimetidine. Both oral and IV cimetidine decreased theophylline clearance to the same extent. However, when clearance was corrected for cimetidine AUC, oral cimetidine resulted in a greater inhibition than IV cimetidine. Thus, the potential for increased inhibitory effect of oral cimetidine was balanced by decreased absorption after oral administration. Degree of inhibition (absolute change in theophylline clearance) and percent of inhibition after cimetidine correlated with the basal theophylline clearance. Individuals with higher basal theophylline clearances had greater degree and percent of inhibition than individuals with lower basal theophylline clearances.

Lack of endogenous crossreactivity with three digitoxin radioimmunoassays in adults with renal insufficiency.

The possibility of interference by apparent digitoxin-like immunoreactive substance (DTLIS) with three radioimmunoassays was studied in patients with renal insufficiency. From each of 25 adult patients with renal insufficiency and 25 age-matched and sex-matched control subjects with normal renal function, a single serum sample was obtained and assayed for digitoxin content by three commercially available radioimmunoassays (GammaCoat, Coat-A-Count, and the Wien assay). Although two of the three assays found measurable concentrations, the difference in apparent digitoxin concentrations between the control subjects and those with renal insufficiency was not significant. Assay interference could not be explained on the basis of differences in age, serum creatinine concentration, or weight. The magnitude of DTLIS interference in relation to the digitoxin therapeutic range appears to be small with the radioimmunoassays used in this study.