Simultaneous measurement of adenosine triphosphate release and aggregation potentiates human platelet aggregation responses for some subjects, including persons with Quebec platelet disorder.

Platelet aggregometry and dense granule adenosine triphosphate (ATP) release assays are helpful to diagnose platelet disorders. Some laboratories simultaneously measure aggregation and ATP release using Chronolume® a commercial reagent containing D-luciferin, firefly luciferase and magnesium. Chronolume® can potentiate sub-maximal aggregation responses, normalising canine platelet disorder findings. We investigated if Chronolume® potentiates human platelet aggregation responses after observing discrepancies suspicious of potentiation. Among patients simultaneously tested by light transmission aggregometry (LTA) on two instruments, 18/43 (42%), including 14/24 (58%) with platelet disorders, showed full secondary aggregation with one or more agonists only in tests with Chronolume®. As subjects with Quebec platelet disorder (QPD) did not show the expected absent secondary aggregation responses to epinephrine in tests with Chronolume®, the reason for the discrepancy was investigated using samples from 10 QPD subjects. Like sub-threshold ADP (0.75 µM), Chronolume® significantly increased QPD LTA responses to epinephrine (p<0.0001) and it increased both initial and secondary aggregation responses, leading to dense granule release. This potentiation was not restricted to QPD and it was mimicked adding 1-2 mM magnesium, but not D-luciferin or firefly luciferase, to LTA assays. Chronolume® potentiated the ADP aggregation responses of QPD subjects with a reduced response. Furthermore, it increased whole blood aggregation responses of healthy control samples to multiple agonists, tested at concentrations used for the diagnosis of platelet disorders (p values <0.05). Laboratories should be aware that measuring ATP release with Chronolume® can potentiate LTA and whole blood aggregation responses, which alters findings for some human platelet disorders, including QPD.

SU-E-T-197: A Comprehensive Variance Reporting System and an Analysis of Variances Reported at Our Institution.

PURPOSE: It is essential for radiation oncology departments to have comprehensive patient safety and quality programs. Two years ago we undertook a systematic review of our safety/QA program. Existing policies were updated and new policies created where necessary. One crucial component of any safety/QA program is continually updating it based on current information, the 'check' and 'act' portions of the Deming Cycle. We accomplished this with a transparent variance reporting system and a safety/QA committee reviewing and acting on reported variances. METHODS: With 5 radiation oncology centers in our institution, we needed to devise a system that would allow anyone to report a variance and provide our QA committee the ability to review variances system-wide. We developed the system using web-based tools. The system allows individuals to report variances, anonymously or named, specify the nature of the variance and indicate the tools used to identify the variance. RESULTS: In 2011, 285 variances were reported, 102 were reported by physicists, 86 anonymously, 71 by therapists and 26 by dosimetrists. We realized the need to develop clear classifications for variances. We added a high priority category, defined as variances which resulted in or had the potential to result in harm to a patient or when a policy is purposely overridden. Of the 285 variances reported, 5 were high priority. We created a process variance category, defined as variances where a specific clinical process is not followed. Of the 285 reported variances 155 were process variances. CONCLUSIONS: Reporting of variances through a centralized database is central toward developing a robust patient safety/quality assurance program. Anonymous reporting fosters a non-punitive environment, and promotes the 'safety culture'. The goal of such a system is to review trends in clinical processes and ultimately to improve safety/quality by reducing variances associated with these processes.

[Influence between early maladaptive schemas and depression]. / L'influence entre les schémas précoces inadaptés et la dépression.

INTRODUCTION: Early maladaptive schemas developed during childhood are relatively stable. Once activated, these early maladaptive schemas could influence reality perceptions and create cognitive distortions. Previous studies showed that early maladaptive schemas are linked to depression: early maladaptive schemas could be a risk factor for depression (Young, 2001) and a vulnerability marker for depression (Dozoïs, 2007). OBJECTIVES: The main objective of the present study was to explore the influence of early maladaptive schemas on depression severity among a French adult population. METHOD: One hundred and sixty-two participants (mean age 29 years; SD=13.86) were enrolled, 66 men (mean age 29 years; SD=13.65) and 106 women (mean age 30; SD=14.07). Participants were invited to complete the Young Schema Questionnaire, short version (YSQ-S1-Young 1994) and the Beck depression Inventory, 2nd version (BDI-II-Beck 1994). Fifty-six participants were randomly selected to complete a paper version of the scales, and 95 participants completed an online electronic version. RESULTS: Fifty-two percent of the participants were not depressed, 15% slightly depressed, 17% moderately depressed and 16% met criteria of severe depression. All 15 schemas scores were positively correlated to depression scores. Comparing schema scores and depression severity it can be noted that for severely depressed participants all schema scores were significantly higher, and six of 15 schemas were significantly higher in the case of moderate depression. In addition, three schemas (imperfection, vulnerability, fusional relation) are significantly and positively linked to depression scores, whereas one schema (everything is owed to me) appears to be a significantly negative predictor of associated depression. CONCLUSION: This study confirms results of previous research concerning the link between early maladaptive schemas and depression. What is more, the results show that the importance of these schemas increases with depression severity. The most important variation was found on schemas concerning interpersonal relationships like "abandonment" or "social insulation and social exclusion" as well as schemas related to personal competence as for example "failure" or "dependence and incompetence". Further research will be necessary to explore the role of depression as an activator or/and by reinforcing early maladaptive schemas.

Microtubule-destabilizing agents: structural and mechanistic insights from the interaction of colchicine and vinblastine with tubulin.

Microtubules (MTs) are dynamic structures of the eukaryotic cytoskeleton that, during cell division, form the mitotic spindle. Perturbing them leads to mitotic arrest and ultimately to cell death. Consistently, MTs and their building block, αß tubulin, are one of the best characterized targets in anti-cancer chemotherapy. Drugs that interfere with MTs either stabilize or destabilize them. The latter class is the subject of this review. These ligands bind to the colchicine site or to the vinca domain, two distinct sites located at a distance from each other on tubulin. Nevertheless the effects of both classes of ligands share a common theme, they prevent the formation of MT specific contacts, therefore triggering their disassembly.

Targeted in vivo expression of nicotinic acetylcholine receptors in mouse brain using lentiviral expression vectors.

Nicotinic acetylcholine receptors (nAChRs) in the brain exhibit diverse functional properties and ubiquitous distribution. Yet, except for providing a receptor for the exogenously applied nicotine of tobacco products, their role in the normal functioning of the brain has remained elusive. We have used a lentiviral expression vector to re-express the beta2 subunit specifically in the ventral tegmental area (VTA) of beta2-/- mice. The viral vector efficiently expresses beta2- subunit protein leading to new nAChR-binding sites. VTA neurons transduced by the lentiviral vector are responsive to intravenous nicotine when analyzed using in vivo electrophysiology. Nicotine-induced dopamine release from the nucleus accumbens (NuAcc) was also restored in re-expressing beta2-/- mice. Intra-VTA injection of nicotine was found to be reinforcing in both wild-type and beta2-subunit re-expressing beta2-/- mice, but not in beta2-/- mice. Furthermore, in the absence of applied nicotine, the spontaneous slow exploratory behavior of the mice was restored, whereas fast navigation did not change. This latter behavioral analysis suggests a role for beta2* nAChR, specifically expressed in the VTA, in mammalian cognitive function.

Genetic dissociation of two behaviors associated with nicotine addiction: beta-2 containing nicotinic receptors are involved in nicotine reinforcement but not in withdrawal syndrome.

RATIONALE: Nicotine addiction is characterized by two distinct behaviors, chronic compulsive self-administration and the induction of a withdrawal syndrome upon cessation of nicotine consumption. OBJECTIVE: To examine if these two processes rely on beta2-containing nicotinic receptors--beta2*nAChRs--we analyzed the behavior of mice lacking these receptors in the two situations. RESULTS: First, we showed that, in contrast to wild-type (WT) mice, beta2-knockout (beta2-/-) mice exhibit no intra-ventral tegmental area (VTA) nicotine self-administration, whereas their ability to self-administer morphine is intact. However, beta2-/- mice showed some sensitivity to locomotor effects of nicotine, implying an effect of the drug on other nicotinic subtypes. Then, we observed that beta2-/- mice exhibited a normal nicotine withdrawal syndrome, i.e., increased levels of rearing and jumping upon precipitated withdrawal. Thus, the beta2*nAChRs are not involved in the behaviors induced by cessation of nicotine consumption. CONCLUSION: Taken together, the present data demonstrated a genetic dissociation of two distinct behavioral patterns associated with nicotine addiction. They further suggested that independent molecular mechanisms underlie these two aspects, offering the possibility of controlling them separately.

Nicotine reinforcement and cognition restored by targeted expression of nicotinic receptors.

Worldwide, 100 million people are expected to die this century from the consequences of nicotine addiction, but nicotine is also known to enhance cognitive performance. Identifying the molecular mechanisms involved in nicotine reinforcement and cognition is a priority and requires the development of new in vivo experimental paradigms. The ventral tegmental area (VTA) of the midbrain is thought to mediate the reinforcement properties of many drugs of abuse. Here we specifically re-expressed the beta2-subunit of the nicotinic acetylcholine receptor (nAChR) by stereotaxically injecting a lentiviral vector into the VTA of mice carrying beta2-subunit deletions. We demonstrate the efficient re-expression of electrophysiologically responsive, ligand-binding nicotinic acetylcholine receptors in dopamine-containing neurons of the VTA, together with the recovery of nicotine-elicited dopamine release and nicotine self-administration. We also quantified exploratory behaviours of the mice, and showed that beta2-subunit re-expression restored slow exploratory behaviour (a measure of cognitive function) to wild-type levels, but did not affect fast navigation behaviour. We thus demonstrate the sufficient role of the VTA in both nicotine reinforcement and endogenous cholinergic regulation of cognitive functions.

Nodular osteochondrogenic activity in soft tissue surrounding osteoma in neurogenic para osteo-arthropathy: morphological and immunohistochemical study.

BACKGROUND: Neurogenic Para-Osteo-Arthropathy (NPOA) occurs as a consequence of central nervous system injuries or some systemic conditions. They are characterized by bone formation around the main joints. METHODS: In order to define some biological features of NPOAs, histological and immunohistological studies of the soft tissue surrounding osteoma and Ultrasound examination (US) of NPOA before the appearance of abnormal ossification on plain radiographs were performed. RESULTS: We have observed a great number of ossifying areas scattered in soft tissues. US examination have also shown scattered ossifying areas at the early stage of ossification. A high osteogenic activity was detected in these tissues and all the stages of the endochondral process were observed. Mesenchymal cells undergo chondrocytic differentiation to further terminal maturation with hypertrophy, which sustains mineralization followed by endochondral ossification process. CONCLUSION: We suggest that periosteoma soft tissue reflect early stage of osteoma formation and could be a model to study the mechanism of osteoma formation and we propose a mechanism of the NPOA formation in which sympathetic dystony and altered mechanical loading induce changes which could be responsible for the cascade of cellular events leading to cartilage and bone formation.

Nicotine protects rat brain mitochondria against experimental injuries.

Epidemiological studies have reported that cigarette smoking may protect from neurodegenerative diseases such as Parkinson's disease. These protective effects are thought to be mediated by nicotine. Recent data showed that nicotine significantly decreases respiratory control ratio (RCR) and superoxide anion generation of brain mitochondria. Thus, we investigated nicotine effects on rat brain in two experimental models: first, an in vitro anoxia/reoxygenation experiment and secondly, an in vivo rotenone-induced Parkinson-like syndrome. Anoxia/reoxygenation impaired mitochondrial respiration by 43.68% whereas in the presence of nicotine, it was less impaired, by 31.1% at 10(-7) M. In rats chronically administered rotenone (3 mg/kg/day), we observed profound mitochondrial damage: the RCR decreased by 50.36% and the superoxide anion generation and the membrane anisotropy increased by 56.03 and 13.43%, respectively. All of these indications of mitochondrial damage were limited by chronic administration of nicotine. Nicotine developed mitochondrial effects in vivo and in vitro at very low concentration. All these results were in accordance with epidemiological studies, which report a protective effect of nicotine in neurodegenerative diseases. Thus, we propose that one effect of nicotine is to preserve mitochondrial functions of the rat central nervous system.

In vitro effects of nicotine on mitochondrial respiration and superoxide anion generation.

In this study, we investigated the effects of nicotine on rat brain mitochondria. The polarographic studies determined the effects on the respiratory chain, whereas enzymatic assays and [3H]-nicotine binding allowed us to precisely identify its target and site of action. The measurements of oxygen consumption showed a significantly concentration-dependent inhibition by nicotine (EC50 was 4.95x10(-11) M), and a maximal decrease of 23.90% at 10(-7) M. Nicotine bound to complex I of the respiratory chain and inhibited the NADH-Ubiquinone reductase activity. We also showed that nicotine and NADH were competitive on complex I. Effects of cotinine, the main nicotine metabolite, and nornicotine, were also investigated: nornicotine inhibited the mitochondrial respiration whereas cotinine did not. Because the complex I generates superoxide anion, we investigated the effects of nicotine, following NBT oxidation, and showed that nicotine was able to inhibit this reactive oxygen species (ROS) generation by 15.74% with an EC50 of 2.02x10(-11) M. In conclusion, the present study shows that nicotine interacts with the complex I of brain mitochondrial respiratory chain and decreases ROS generation. This may explain a part of the beneficial and protective effects of nicotine in few neurodegenerative diseases, as suggested by many epidemiological studies.

L-365,260 inhibits in vitro acid secretion by interacting with a PKA pathway.

The aim of this study was to analyse the antisecretory mechanism of L-365,260 in vitro in isolated rabbit gastric glands. We showed that compound L-365,260, described as a non-peptide specific competitive CCK-B receptor antagonist, was able to dose-dependently inhibit [14C]-aminopyrine accumulation induced by histamine (10(-4) M), carbachol (5x10(-5) M), 3-isobutyl-1-methyl-xanthine (IBMX) (5x10(-6) M) and forskolin (5x10(-7) M) with similar IC50 values respectively of 1.1+/-0.6x10(-7) M, 1.9+/-1.2x10(-7) M, 4.2+/-2.0x10(-7) M and 4.0+/-2.8x10(-7) M. We showed that L-365,260 acted beyond receptor activation and production of intracellular second messengers and that it had no action on the H+/K+ -ATPase. We found that L-365,260 inhibited cyclic AMP-induced [14C]-aminopyrine accumulation in digitonin-permeabilized rabbit gastric glands, suggesting that this compound acted, at least in part, as an inhibitor of the cyclic AMP-dependent protein kinase (PKA) pathway.

A problem associated with the use of a calomel reference electrode in an ISE analytical system.

It was discovered during the testing of a new diluted ISE analytical system that a dark deposit formed in the vicinity of the reference electrode junction and on the junction membrane over a 1-3 month period of use. The effect of the black deposit was to shorten the life of the restricted flow reference membrane and increase the time required to maintain the system in its optimum state. Elemental analysis of the deposit revealed the presence of both mercury and sulfur. The rate of deposit build-up was found to depend on the concentrations of both the buffer and the microbicide in the system's reagents. The cause was traced in part to the generation of sulfide ions as a breakdown product of the microbicide. The disproportionation of calomel, Hg2Cl2, in saturated KCl to give Hg2+chloro-complexes and their reaction with sulfide ions at the reference junction resulted in HgS being deposited. Design changes over previous systems contributed to the effect by increasing residence time of calibrant solution at the reference junction and decreasing the frequency of reference electrolyte and membrane changes. Adding complexing agents to the reference fill solution lessened but did not eliminate the problem. The problem was solved without reformulating the reagents by using a reducing agent proximate to the calomel mercury amalgam to reduce mercuric ions to metallic mercury. This also prevents discharge of environmentally undesirable mercuric ions into the waste solution.

Survey of food-related waste management practises in New Brunswick health establishments.

A survey was conducted jointly by Université de Moncton and the New Brunswick (N.B.) Department of Health and Community Services to generate information on waste management practises within health care institutions. The objectives of the survey were: 1) to identify the type of waste management methods in place in N.B. health establishments; 2) to identify the major difficulties associated with recycling food-related waste; 3) to study the attitudes and beliefs of food service managers toward waste management. Data were collected through a questionnaire mailed to food service managers. Results indicated that 86% of establishments were involved in waste reduction. There were no statistically significant differences in reduction practices between hospitals and nursing homes or between the size of these establishments (P = 0.11). The same applied for reutilization (P = 0.09) where 93% of the establishments were involved. Recycling was carried out in 64.8% of the establishments. Major obstacles to recycling included the lack of pickup services, the lack of storage space, and the absence of buyers for recyclable materials. The results of this survey will help in the formulation of policies, strategies, and recommendations for better protection of the environment.

Frozen human serum reference material for standardization of sodium and potassium measurements in serum or plasma by ion-selective electrode analyzers.

Three interlaboratory round-robin studies (RR1, RR2, and RR3) were conducted to identify a serum-based reference material that would aid in the standardization of direct ion-selective electrode (ISE) measurements of sodium and potassium. Ultrafiltered frozen serum reference materials requiring no reconstitution reduced between-laboratory variability (the largest source of imprecision) more than did other reference materials. ISE values for RR3 were normalized by the use of two points at the extremes of the clinical range for sodium (i.e., 120 and 160 mmol/L), with values assigned by the flame atomic emission spectrometry (FAES) Reference Method. This FAES normalization of ISE raw values remarkably improved all sources of variability and unified the results from seven different direct ISE analyzers to the FAES Reference Method value. Subsequently, a three-tiered, fresh-frozen human serum reference material was produced to the specifications developed in RR1-RR3, was assigned certified values for sodium and potassium by Definitive Methods at the National Institute of Standards and Technology (NIST), and was made available in 1990 to the clinical laboratory community as a Standard Reference Material (SRM); it is now identified as SRM 956. Albeit retrospectively, we show how applying an FAES normalization step identical to that used in RR4/5 to the ISE data for SRM 956 after the NIST Definitive Method values were known, consistently moved the ISE results for RR3 closer to the true value for Na+ and K+.

Efficacy of sequential cyclical hormonal therapy in endometrial cancer and its correlation with steroid hormone receptor status.

Forty-six eligible women with metastatic endometrial cancer were randomly allocated to receive monthly cycles of either CAF (cyclophosphamide, adriamycin, 5-fluorouracil) or CAF plus Provera 200 mg daily for 3 weeks followed cyclically by Tamoxifen 20 mg daily for 3 weeks. Overall response rates of 15 and 43% were seen with CAF and CAF plus hormonal therapy. Using a multivariate analysis of the results, this difference is significant (P value 0.05). In 8 patients with operable endometrial cancer, negative estrogen receptor concentration (ER less than 15 fmole/mg protein) and Grade 3 disease, the clinical course was aggressive in 4 patients with systemic and local relapse. In 10 other similar patients (negative ER and Grade 3) who received adjuvant cyclical hormonal therapy only 1 relapsed and the other 9 are disease-free for an average of more than 31 months. Sequential cyclical hormonal therapy with ER and progesterone receptor analysis has a place in the management of endometrial carcinoma.

Value of lymphography in Stage IB cancer of the uterine cervix.

In many neoplasms, lymphography is a reliable method with which lymph node metastases are demonstrated, but its accuracy in Stage IB cancer of the uterine cervix remains to be more firmly established. One hundred patients with Stage IB cancer of the uterine cervix underwent lymphography before radical hysterectomy with pelvic lymphadenectomy was contemplated. All the lymphographic findings were reviewed without knowledge of the pathologic parameters of the patients and were classified as being either positive (five cases), suspicious (15 cases), or negative (80 cases). The pathologic studies revealed lymph node metastases in 18 patients--in five with positive lymphographic findings, in three with suspicious findings, and in 10 with negative ones. The five true positive cases were compared to the 13 false negative or suspicious lymphographic results. It appears that the former have a greater number of involved lymph nodes and a greater mean size of the metastases. Thus, in Stage IB cancer of the uterine cervix, lymphography demonstrates an excellent specificity (100%) but a low sensitivity (27.8%).