Interference between multipolar two-photon transitions in quantum emitters near plasmonic nanostructures.

In the vicinity of plasmonic nanostructures that support highly confined light fields, spontaneous emission processes, such as two-photon spontaneous emission (TPSE), exhibit higher-order multipolar emission pathways beyond the dipolar one. These multipolar emission channels occur simultaneously and can interfere with each other. We develop a novel framework that computes these interference effects for TPSE of a quantum emitter close to an arbitrary nanostructure. The model is based on the computation of Purcell factors that can be calculated with conventional electromagnetic simulations, which avoids complex analytic calculations for the environment. For a transition of a hydrogen-like emitter close to a graphene nanotriangle, we demonstrate a breakdown of the dipolar selection rule in the TPSE process. This breakdown is due to a huge enhancement of the two-electric dipole (2ED) and of the two-electric quadrupole (2EQ) transitions. We observe an important interference between these multipolar transitions, as it increases the total rate by 67 % . In the end, our framework is a complete tool to design emitters and nanostructures for TPSE, where the exploitation of previously ignored interference effects provides an additional degree of freedom, for example to boost desired transitions and to supress undesirable ones.

Quality of stapled mesenteric defect closure influences the chance of reopening after laparoscopic Roux-en-Y gastric bypass surgery.

Internal herniation (IH) is a common problem after laparoscopic Roux-en-Y gastric bypass surgery (RYGB). Routine closure of the mesenteric defects (MDs) reduces the risk of IH. Only very few articles report on risk factors for IH or describe detailed closing techniques. There is no consensus yet on the best closing method. The objective of this study is to determine the optimal stapling method for closure of MDs after RYGB. All performed RYGB procedures in our high-volume bariatric institute were included. Quality of the closure was scored in the categories poor, sub-optimal, and optimal, to see if the quality of the closure would predict the chance of reopening of the MDs and, therefore, the chance of IH. During any type of laparoscopy in the follow-up of the patient, the conditions of the MDs were stated, for example during diagnostic laparoscopy in symptomatic patients suspicious for IH or during laparoscopic cholecystectomy. Technically well-executed closure of Petersen's space (PS) with two rows of staples had a greater chance of still being closed upon re-inspection compared to closure with one row (odds ratio = 8.1; 95% confidence interval [1.2-53.2], p = 0.029). Optimal closure of the MD at the jejuno-jejunostomy (JJ-space, JJS) resulted in more closed JJSs upon re-inspection compared to sub-optimal closure (odds ratio = 3.6 [CI 95% 0.8-16.1], p = 0.099). Non-optimally closed MDs had higher reopening rates and, therefore, pose an additional risk for IH. Our classification provides a quality assessment of MD closure during RYGB and gives insight into how to optimize surgical technique.

Treatment of cryptoglandular fistulas with the fistula tract laser closure (FiLaC™) method in comparison with standard methods: first results of a multicenter retrospective comparative study in the Netherlands.

BACKGROUND: Current surgical closure techniques for sphincter-sparing treatment of high cryptoglandular fistulas in the Netherlands include the mucosal advancement flap procedure (MAF) and ligation of the intersphincteric fistula tract (LIFT). A relatively novel treatment is the fistula tract laser closure (FiLaC™) method. The aim of this study was to investigate the differences in healing and recurrence rates between FiLaC™ and current standard practices. METHODS: This multicenter retrospective cohort study included both primary and recurrent high cryptoglandular anorectal fistulas, treated with either FiLaC™ or standard methods (MAF or LIFT) between September 2015 and July 2020. Patients with extrasphincteric fistulas, Crohn's disease, multiple fistulas, age < 18 years or missing data regarding healing time or recurrence were excluded. The primary outcomes were the clinical primary and secondary healing and recurrence rates. Primary healing was defined as a closed external opening without fluid discharge within 6 months of treatment on examination, while secondary healing was the same endpoint after secondary treatment. Secondary outcomes included healing time and complaints. RESULTS: A total of 162 high fistulas from 3 Dutch hospitals were included. Ninety-nine high fistulas were treated with FiLaC™ and 63 with either MAF or LIFT. There were no significant differences between FiLaC™ and MAF/LIFT in terms of clinical healing (55.6% versus 58.7%, p = .601), secondary healing (70.0% versus 69.2%, p = .950) or recurrence rates (49.5% versus 54%, p = .420), respectively. Median follow-up duration was 7.1 months in the FiLaC™ group (interquartile range [IQR] 4.1-14.4 months) versus 6 months in the control group (IQR 3.5-8.1 months). CONCLUSIONS: FiLaC™ treatment of high anorectal fistulas does not appear to be inferior to MAF or LIFT. Based on these preliminary results, FiLaC™ can be considered as a worthwhile treatment option for high cryptoglandular fistulas. Prospective studies with a longer follow-up period and well-determined postoperative parameters such as complication rates, magnetic resonance imaging for confirmation of fistula healing, incontinence and quality of life are warranted.

Isolated amyloidosis of the gastro-intestinal tract.

Amyloidosis is a very rare condition, which, due to its rarity, is often missed or diagnosed in an advanced stage of the disease, causing significant morbidity and mortality. In this review we describe the existing types of amyloidosis focusing on the gastro-intestinal tract. Amyloidosis occurs when abnormal protein fibrils (amyloid) deposit in the muscularis mucosae. This can cause an array of symptoms ranging from (in order of occurrence): gastro-intestinal bleeding, heartburn, unintentional weight loss, early satiety, constipation, diarrhea, nausea, vomiting and fecal incontinence (1). Treatment is focused on the underlying condition (if any) causing the production and deposition of the abnormal fibrils, in combination of symptomatic treatment.

Effects of early life and current housing on sensitivity to reward loss in a successive negative contrast test in pigs.

Animals in a negative affective state seem to be more sensitive to reward loss, i.e. an unexpected decrease in reward size. The aim of this study was to investigate whether early-life and current enriched vs. barren housing conditions affect the sensitivity to reward loss in pigs using a successive negative contrast test. Pigs (n = 64 from 32 pens) were housed in barren or enriched conditions from birth onwards, and at 7 weeks of age experienced either a switch in housing conditions (from barren to enriched or vice versa) or not. Allotting pigs to the different treatments was balanced for coping style (proactive vs. reactive). One pig per pen was trained to run for a large reward and one for a small reward. Reward loss was introduced for pigs receiving the large reward after 11 days (reward downshift), i.e. from then onwards, they received the small reward. Pigs housed in barren conditions throughout life generally had a lower probability and higher latency to get the reward than other pigs. Proactive pigs ran overall slower than reactive pigs. After the reward downshift, all pigs ran slower. Nevertheless, reward downshift increased the latency and reduced the probability to get to the reward, but only in pigs exposed to barren conditions in early life, which thus were more sensitive to reward loss than pigs from enriched early life housing. In conclusion, barren housed pigs seemed overall less motivated for the reward, and early life housing conditions had long-term effects on the sensitivity to reward loss.

Cardiac overscreening hip fracture patients.

BACKGROUND: The aim of this study was to prospectively investigate the adherence to the American College of Cardiology (ACC) and the American Heart Association guidelines for perioperative assessment of patients with hip fracture in daily clinical practice and how this might affect outcome. METHODS: This prospective cohort study from Maastricht University Medical Centre included 166 hip fracture patients within a 3-year inclusion period. The preoperative cardiac screening and adherence to the ACC/AHA guideline were analyzed. Cardiac risk was classified as low, intermediate and high risk. Secondary outcome measurements were delay to surgery, perioperative complications and in-hospital, 30-day, 1-year and 2-year mortality. RESULTS: According to the ACC/AHA guideline, 87% of patients received correct preoperative cardiac screening. The most important reason for incorrect preoperative cardiac screening was overscreening (> 90%). Multivariate analysis showed that a cardiac consultation (p = 0.003) and overscreening (p = 0.02) as significant predictors for increased delay to surgery, while age, sex, previous cardiac history and preoperative mobility were not. High risk patients had in comparison with low risk patients a significantly higher relative risk ratio for in-hospital mortality (RR 6, 95% CI 2-17). Multivariate analysis showed that a previous cardiac history and increased delay to surgery were predictors for early mortality. High age and previous cardiac history were risk factors for late mortality. CONCLUSION: Preoperative cardiac screening for hip fracture patients in adherence to the ACC/AHA guideline is associated with a diminished use of preoperative resources. Overscreening leads to greater delay to surgery, which poses a risk for perioperative complications and early mortality. LEVEL OF EVIDENCE: II.

Effect of blood transfusion on survival after hip fracture surgery.

BACKGROUND: Our primary goal was to audit the incidence of erythrocyte blood transfusion (EBT) after hip fracture surgery and study the effects on perioperative complications and early and late mortality. METHODS: In a retrospective cohort study all patients 65 years old and above treated operatively for an acute hip fracture were included over a 48-month period with a 2-year follow-up period. Postoperative hemoglobin levels were used to investigate at what threshold EBT was used. The relation between EBT and perioperative complications and survival was analyzed with multivariate regression analysis. A propensity score for predicting the chance of receiving an EBT was calculated and used to differentiate between transfusion being a risk factor for mortality and other related confounding risk factors. Mortality was subdivided as in-hospital, 30-day, 1-year and 2-year mortality. RESULTS: Of the 388 included patients, 41% received a blood transfusion. The postoperative hemoglobin level was the strongest predictor for EBT. Patients who received EBT had a significant longer hospital stay and more postoperative cardiac complications, even after adjustment for confounders. Multivariate analysis for mortality showed that EBT was a significant risk factor for early as well as late mortality, but after adding the propensity score, EBT was no longer associated with increased mortality. CONCLUSION: There was no effect of EBT on mortality after correction with propensity scoring for predictors of EBT. Transfusion in patients treated operatively for hip fracture should be evenly matched with their cardiovascular risk during the perioperative phase.

Z-effect after intramedullary nailing systems for trochanteric femur fractures.

PURPOSE: The aim of this study was to investigate the incidence of Z-effect after dual lag screw intramedullary nailing systems and risk factors contributing to this effect. We hypothesized that long nails provide more neck strength due to a longer lever than short nails and are therefore less likely to develop a misbalance of a higher head compressive strength than neck compressive strength. METHODS: In this retrospective cohort study 103 patients treated operatively with a dual lag screw intramedullary nailing device for (sub)trochanteric hip fracture were included. We analysed patient charts regarding patient and operation characteristics. Furthermore we conducted radiologic measurements within the 2-year follow-up period to investigate the quality of fracture fixation, implant failure and predictors for Z-effect. The re-operation risk was investigated with multivariate regression analysis. RESULTS: The incidence of (reversed) Z-effect in this study was 9% (n = 80); 6 out of 7 Z-effects occurred in the short nail group, which was not significant. Patients who were treated with a long nail had a significant larger number of complications in comparison with the short nail group (median 2 vs 0.5, p = 0.001). The long nail group received more often erythrocytes blood transfusions (82% vs 31%, p < 0.01) and had a longer hospital stay (13 vs 21 days, p < 0.05). Migration of lag screws (p <0.05) and unstable fracture type (p < 0.05), were risk factors for re-operation. The re-operation rate within 2 year after surgery was 21%, of which one fourth was due to a Z-effect. CONCLUSION: The nail length was not associated with the development of a Z-effect. Migration of lag screws after intramedullary nailing is common and a risk factor for re-operation.

[Use of therapeutic hypothermia in sudden unexpected postnatal collapse]. / Malaise grave inopiné du nouveau-né à terme : une place possible pour l'hypothermie thérapeutique.

Sudden postnatal collapse of a full-term newborn is uncommon but may result in severe consequences: these include death; epilepsy; and motor, cognitive, or sensory impairment. Most authors suggest applying a therapeutic hypothermia approach when a previously healthy newborn develops moderate or severe encephalopathy after a sudden postnatal collapse occurring within the first hours or days after birth. However, this technique has still not been validated by randomized trials. Only a few cases have been reported in the literature. This article describes five apparently healthy newborns, born between 2007 and 2012, who suffered moderate to severe encephalopathy following a postnatal collapse on their first day of life. It describes their clinical history as well as their treatment and follow-up. The article focuses on the implementation of hypothermia in this indication and its limitations. Two newborns underwent classic therapeutic hypothermia, two others underwent temperature regulation (one at 34.5 °C, the other one for only 15 h because she quickly improved). One newborn, with severe pulmonary arterial hypertension, did not receive therapeutic hypothermia. Two newborns died (one had classic hypothermia and the other hypothermia at 34.5 °C), the outcome of the three survivors at three years, 18 months, and 15 months is good with only transient postural anomalies. Follow-up must be continued to assess their cognitive development and particularly their memorization processes. Additional research and centralization of the cases is required to evaluate the feasibility, safety, and benefits of therapeutic hypothermia in this situation.

[Patients with brain injury in a psychiatric setting; assessment of health care needs and received care]. / Klinische patiënten met niet-aangeboren hersenletsel in de ggz; inventarisatie van zorgbehoeftes en ontvangen zorg.

BACKGROUND: In some Dutch mental health care organisations specific neuropsychiatric departments have been developed for patients with brain injury. AIM: To identify the characteristics of patients with brain injury who form a specific population in mental health care and to determine whether such patients require either specialised care or a special type of care. METHOD: A cross-sectional analysis of typical brain injury inpatients was performed. We noted the age and gender of these patients and recorded any previous periods of inpatient care. We listed patients' impairments, the diagnoses they had been given and the treatment they had received. This inventory formed the basis of our conclusions. RESULTS: The typical clinical patient with brain injury in this setting was a male of 51 years or older, most probably affected by a stroke or traumatic brain injury, admitted for a period of 6 months, many years after the incident. He was mostly referred from home or hospital by a physician and was expected to return home again. A combination of cognitive and psychiatric impairments was often found. Physically the patient had no or only mild disabilities, but societal participation was low and many cognitive-affective disorders were seen. Treatment was relatively infrequent and mostly directed at daily activities. The most frequent diagnosis was & lquo;cognitive deficits not otherwise specified'. Irritability, agitation, apathy and depression were frequent symptoms. CONCLUSION: This inventory suggests that brain injury patients in a mental health care setting need special care which is not available in other health care settings.

Preoperative cardiac evaluation of geriatric patients with hip fracture.

BACKGROUND: The American College of Cardiology (ACC) and the American Heart Association (AHA) have developed guidelines for perioperative assessment of patients in case of non-cardiac surgery. The aim of this study was to investigate if the preoperative cardiac evaluation of geriatric patients with hip fracture was in accordance with these guidelines and what the effects were on outcome. METHODS: In a retrospective study 388 patients with hip fracture treated in the department of Trauma surgery of the Maastricht University Medical Centre in the Netherlands were included. All patients were treated between 2003 and 2006 and had at least two year follow-up. The preoperative cardiac screening was analysed with respect to content and to which level this followed the ACC/AHA guidelines. These guidelines were used to classify cardiac risk into low, intermediate and high risk. This was related to the outcome measurements delay to surgery, perioperative complications and mortality. RESULTS: According to the ACC/AHA guidelines 82% of patients received correct preoperative cardiac screening in the low vs. 46% in the intermediate and 86% in the high risk group. The most frequent reason for incorrect preoperative cardiac screening was overscreening (>95%). The delay to surgery increased by 9.9h in the case of overscreening (p=0.03). A previous cardiac history was a significant risk factor for early mortality. Delay of >48 h was associated with more cardiovascular complications and mortality both on univariate and multivariate analysis. CONCLUSION: Preoperative cardiac screening is frequently unnecessary after hip fracture, especially in patients with intermediate risk predictors and increases the delay to surgery. Delay of >48 h was associated with more cardiovascular complications and mortality postoperatively. The implementation of the ACC/AHA guidelines may prevent unnecessary cardiac consultations which reduces preoperative resources, delay to surgery and possibly decreases postoperative complications.

[Implementation of the intestinal micro flora in the early stage and adequate immunity later on]. / Etablissement du microbiote intestinal en bas âge et qualité de l'immunité ultérieure.

The pre and postnatal development of human immunity are remarkably continuous. The feto-placental unit builds up to promote a climate of immune tolerance specifically driven in this way by the maternal immunity. The process of birth triggers the development of the infant's postnatal immunity, in first place through the bacterial colonisation of a sterile intestinal mucosa. The progressive immune response stabilisation at the sub-mucosa level during the first year of life will arise from the interface between the host and its microflora. It will take place progressively and will occur thanks to a variety of successive and complementary very complex immune mechanisms, under the influence of a rich and diversified intestinal microbiotia. Solid scientific arguments allow hypothesising that immune deviances later in life could be the consequence of an inadequate bacterial pressure on the intestinal mucosa at the early stage. A variety of epigenetic modifications taking place in this early stage could account for the deviant programming of later immunity. Each health care provider should acknowledge that some therapeutic and nutritional interventions during the first year of life may interfere with this complex immune development, giving rise to a risk of increasing immune deviancies later on.

Macrolides inhibit IL17-induced IL8 and 8-isoprostane release from human airway smooth muscle cells.

Lung transplantation is hampered by bronchiolitis obliterans syndrome (BOS), although recently azithromycin treatment has a published response rate of about 42% in patients with established BOS. We linked this improvement to a reduction in airway neutrophilia and IL8. In the present study, we further investigated the intracellular mechanisms of azithromycin, looking at the possible involvement of mitogen-activated-protein kinases (MAPK) and oxidative stress. Simultaneously, currently used immunosuppressive agents were investigated. Human primary airway smooth muscle cells were stimulated with IL17 and incubated with increasing concentrations of steroids, immunosuppressive agents (tacrolimus, cyclosporine and rapamycin) or macrolides (erythromycin and azithromycin). We measured supernatant IL8 protein, 8-isoprostane and cell lysate MAPK. IL17-induced IL8 production was decreased by both erythromycin and azithromycin. In nonstimulated condition, IL8 production only increased at the highest dose of azithromycin. Dexamethasone failed to attenuate IL8 production, whereas immunosuppressive agents significantly increased IL8 production in both IL17-stimulated and nonstimulated conditions. 8-isoprostane production and MAPK activation proved to be decreased by the macrolides. We conclude that macrolides (but not steroids/immunosuppressive agents) inhibit IL17-induced IL8 production in human primary airway smooth muscle cells via a reduction in MAPK activation and 8-isoprostane production. In BOS patients, these phenomena may explain the anti-inflammatory effects of azithromycin.

Genome-wide DNA copy number alterations in head and neck squamous cell carcinomas with or without oncogene-expressing human papillomavirus.

Oncogene-expressing human papillomavirus type 16 (HPV16) is found in a subset of head and neck squamous cell carcinomas (HNSCC). HPV16 drives carcinogenesis by inactivating p53 and pRb with the viral oncoproteins E6 and E7, paralleled by a low level of mutations in TP53 and allelic loss at 3p, 9p, and 17p, genetic changes frequently found in HNSCCs of nonviral etiology. We hypothesize that two pathways to HNSCC exist: one determined by HPV16 and the other by environmental carcinogens. To define the critical genetic events in these two pathways, we now present a detailed genome analysis of HNSCC with and without HPV16 involvement by employing high-resolution microarray comparative genomic hybridization. Four regions showed alterations in HPV-negative tumors that were absent in HPV-positive tumors: losses at 3p11.2-26.3, 5q11.2-35.2, and 9p21.1-24, and gains/amplifications at 11q12.1-13.4. Also, HPV16-negative tumors demonstrated loss at 18q12.1-23, in contrast to gain in HPV16-positive tumors. Seven regions were altered at high frequency (>33%) in both groups: gains at 3q22.2-qter, 5p15.2-pter, 8p11.2-qter, 9q22-34.1, and 20p-20q, and losses at 11q14.1-qter and 13q11-33. These data show that HNSCC arising by environmental carcinogens are characterized by genetic alterations that differ from those observed in HPV16-induced HNSCC, and most likely occur early in carcinogenesis. A number of genetic changes are shared in both tumor groups and can be considered crucial in the later stages of HNSCC progression.

Metabolism and growth inhibition of four retinoids in head and neck squamous normal and malignant cells.

Isotretinoin (13-cis-retinoic acid, 13cRA) has proven to be active in chemoprevention of head and neck squamous cell carcinoma (HNSCC). Moreover, both all-trans-retinoic acid (ATRA) and 13cRA induce objective responses in oral premalignant lesions. After binding of retinoids to retinoic acid receptors (RARs and RXRs) dimers are formed that are able to regulate the expression of genes involved in growth and differentiation. We compared the metabolism and level of growth inhibition of 13cRA with that of ATRA, 9cRA and retinol in four HNSCC cell lines and normal oral keratinocyte cultures (OKC). These retinoid compounds are known to bind with different affinities to the retinoic acid receptors. We observed that all retinoids were similar with respect to their capacity to induce growth inhibition. One HNSCC line could be ranked as sensitive, one as moderately sensitive and the remaining two were totally insensitive; OKC were moderately sensitive. The rate at which the cells were able to catabolize the retinoid was similar for all compounds. Retinoid metabolism in HNSCC cells resulted in a profile of metabolites that was unique for each retinoid. These metabolic profiles were different in OKC. Our findings indicate that differences in retinoid receptor selectivity of these retinoids do not influence the level of growth inhibition and rate of metabolism.

Expression of retinoic acid receptor gamma correlates with retinoic acid sensitivity and metabolism in head and neck squamous cell carcinoma cell lines.

Retinoids, analogues of vitamin A, can reverse premalignant lesions and prevent second primary tumors in patients with head and neck squamous cell carcinoma (HNSCC). The effects of retinoids are mediated by retinoic acid receptors (RARs) and retinoid X receptors (RXRs), which act as ligand-activated transcription factors. The regulation of cell growth, differentiation and retinoid metabolism in normal, premalignant and malignant cells by retinoids is thought to be a result of their effects on gene expression. We investigated mRNA expression of RARs (alpha, beta, and gamma) and RXR-beta by means of RNase protection and related this to retinoic acid (RA)-induced growth inhibition and RA turnover in four HNSCC cell lines (UM-SCC-14C, UM-SCC-22A, UM-SCC-35 and VU-SCC-OE). An RA-resistant subline of UM-SCC-35 was generated by exposure to increasing concentrations of RA for 8 months (designated UM-SCC-35R). RA turnover was determined on the basis of decreasing RA levels in the cells and culture medium after exposure to 1 microM RA. We found that RAR-gamma mRNA expression was strongly correlated with RA-induced growth inhibition (p = 0.016, R = 0.92) and RA turnover (p = 0.041, R = 0.86). RAR-beta transcript levels were reduced in three of five cell lines compared with normal mucosa, and these did not correlate with RA-induced growth inhibition and RA turnover. Expression of RAR-alpha and RXR-beta was not substantially altered in any of the cell lines. These findings suggest that in HNSCC cell lines RAR-gamma is the most important retinoid receptor for regulation of RA turnover rate and RA-induced growth inhibition.

Enhanced turnover of all-trans-retinoic acid and increased formation of polar metabolites in head and neck squamous cell carcinoma lines compared with normal oral keratinocytes.

Retinoids show promise in the treatment of various (pre)malignancies, including head and neck squamous cell carcinoma (HNSCC). Previous studies have shown that the metabolic pathways of retinoids are important in the anticancer effect of retinoids, and that these pathways may change during carcinogenesis. In the present study, we analyzed HNSCC cell lines (n = 11) and normal oral keratinocyte cultures (n = 11) by reverse-phase high-performance liquid chromatography and conducted growth inhibition assays. We demonstrate here that in contrast to normal oral keratinocytes, HNSCC cell lines: (a) had averaged a 17-fold greater turnover rate of all-trans-retinoic acid (RA); (b) had a 1.9-fold less RA-induced growth inhibition; (c) were able to form polar metabolites; and (d) were able to catabolize 4-oxo-RA. Furthermore, the mRNA expression of the RA-specific 4-hydroxylase, CYP26A1, was dramatically increased after RA-induction in the two HNSCC cell lines with the highest metabolism, was undetectable in normal keratinocytes, and was not inducible by RA. Next, introduction of CYP26A1 cDNA in a low-metabolizing HNSCC cell line resulted in an 11-fold higher turnover rate of RA and a 12-fold increase in the amount of polar metabolites, but it did not change sensitivity to RA. These observations point to fundamental changes in RA metabolism pathways during HNSCC carcinogenesis and may provide clues to a more rational approach for RA-mediated intervention.