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.

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.

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.

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.

Effect of cisplatin exposure on platinum accumulation and growth inhibition in human neoplastic and normal squamous epithelial cells of the mucosa of the upper-aerodigestive tract.

The aim of the present study was to investigate how normal head and neck epithelial cells (NHNEC) respond to cisplatin compared to their neoplastic counterparts with respect to intracellular platinum (Pt) levels and growth inhibition. A colorimetric assay was used to assess growth inhibition after exposure to cisplatin for 72 h. Growth inhibition did not differ between cultures of neoplastic (n = 5) and normal cells (n = 5). Intracellular Pt levels, determined with atomic absorption spectroscopy were about 30-fold higher in the normal epithelial cells. The main finding of this study is that normal epithelial cells from the head and neck region have a much higher tolerance for cisplatin than their neoplastic counterparts. Interestingly, this characteristic is without consequence for growth inhibition.

Considerations for in vitro retinoid experiments: importance of protein interaction.

Retinoids, natural and synthetic substances structurally related to vitamin A, are important modulators of cell proliferation and differentiation, and have proven activity in cancer therapy. Experiments to reveal the mechanism of action of retinoids are routinely performed in in vitro models. As retinoids are relatively hydrophobic and unstable, we hypothesized that the composition of culture media is of critical importance for the stability and bioavailability of these compounds. Various culture media were incubated with all-trans-, 13-cis- and 9-cis-retinoic acid (RA). Without fetal calf serum (FCS) or bovine serum albumin (BSA) in the medium, the concentration of these retinoids was found to decrease to considerably low levels. This excessive loss of retinoids was due to absorption to culture plates, reaction tubes and pipet tips. Binding of retinoids to BSA was demonstrated to have attenuating effects on uptake and metabolism of all-trans-RA, as studied in oral keratinocytes and head and neck cancer cells, indicating that a balance exists between the bioavailability and the aspecific loss of retinoids. In this study we demonstrate that the type of culture medium and especially the presence of protein in the medium is of paramount importance to perform reproducible experiments with retinoids.

Exfoliated oral cell messenger RNA: suitability for biomarker studies.

The efficacy of chemoprevention trials can be improved by the use of biomarkers of carcinogenesis that serve as surrogate end points. The aim of this study was to assess the perspectives of using mRNA isolated from oral exfoliated cells for biomarker research in chemoprevention of upper aerodigestive tract cancer. When using reverse transcription-PCR in combination with Southern blotting and hybridization, it was possible to detect transcripts from only five cells. With the quantitative RNase protection assay, we could only detect highly abundant transcripts. The integrity of the RNA was verified by Northern blotting, which showed a variable degree of degradation, depending on the gene studied. Interestingly, although specific transcripts were found to be intact to a certain extent, the rRNA appeared to be completely degraded, suggesting that a specific protein synthesis shut-off mechanism exists in terminally differentiated oral epithelial cells. Altogether, this differential RNA degradation makes accurate measurement of transcript levels of most genes, as determined in exfoliated oral cells, unreliable. Because this RNA degradation process is likely to start before the cells are shed from the tissue, the results of measurements of transcript levels in biopsies of oral tissue should be interpreted with caution.

Onset of action of eformoterol by dry powder inhaler: objective and subjective measures.

This double-blind, randomised, placebo-controlled crossover trial in 18 adults with asthma evaluated the onset of efficacy of doses of 12 and 24 micrograms eformoterol delivered as a dry powder, and compared patients' subjective assessments of efficacy with objective measures. Bronchodilatory efficacy was measured in terms of specific conductance (sGaw) and forced expiratory volume in one minute (FEV1). With both doses of eformoterol, a bronchodilatory effect was observed one minute after inhalation. The difference in bronchodilator effect (sGaw and FEV1) between both eformoterol doses and placebo was statistically significant (p < 0.01) from one minute onwards. No significant difference in onset of action or peak effect was seen between the two doses of eformoterol. Patients' subjective reports were closely related to the observed onset of efficacy and indicated no difference between the two eformoterol doses.

Formoterol as dry powder inhalation. A dose finding study in comparison with formoterol metered dose inhaler and placebo.

We compared the bronchodilator effects and systemic tolerability of 12, 24 and 48 micrograms formoterol DP capsules with 12 micrograms formoterol MDI and placebo in 30 patients with reversible obstructive airway disease. Pulmonary function tests were done and pulse rate and blood pressure were recorded. We observed significant differences between all active substances vs placebo regarding peak effect, duration of effect and AUC value. No significant difference was observed between either 12 or 24 micrograms formoterol DP and 12 micrograms from MDI in all mentioned parameters. With 48 micrograms DP, increased peak effect, AUC and duration of effect were noted. Heart rate Holter monitoring showed a slightly more pronounced effect with 48 micrograms. We conclude that 12 to 24 micrograms formoterol DP capsules are equivalent to 12 micrograms of formoterol MDI regarding efficacy and tolerability, while 48 micrograms formoterol DP capsules cause more profound effects in bronchodilation and on the heart rate.