Roll-your-own tobacco use among Canadian youth: current prevalence and changes in youth smoking "rollies" since 2008.

INTRODUCTION: Roll-your-own (RYO) cigarettes, or "rollies," represent an affordable alternative to manufactured cigarettes, especially among youth with a lower disposable income. This study characterizes changes in the prevalence of RYO tobacco current use between 2008 and 2010 in Canadian youth and examines the sociodemographic characteristics associated with RYO use in 2010. METHODS: This study uses representative data collected from grade 9 to 12 students as part of the 2008/2009 and 2010/2011 cycles of the Canadian Youth Smoking Survey (YSS). RESULTS: Among current smokers, 30.5% currently use RYO cigarettes. Youth with a disposable income of more than $100 each week were less likely to be current RYO users (OR = 0.49, 95% CI: 0.34-0.71). Current RYO tobacco users were more likely to be current alcohol users (OR = 2.01, 95% CI: 1.09-3.72) or marijuana users (OR = 2.63, 95% CI: 1.73-4.01). CONCLUSION: RYO cigarettes continue to provide an affordable alternative to youth smokers. Targeted school-based prevention programs that address the use of RYO cigarettes may offer additional reductions to the use of RYO cigarettes.

TITRE: Prévalence et variation de la consommation de tabac à rouler chez les jeunes Canadiens depuis 2008. INTRODUCTION: Les cigarettes roulées représentent une solution de rechange abordable par rapport aux cigarettes industrielles, en particulier pour les jeunes à faible revenu. Cette étude a pour but de caractériser les variations de prévalence de la consommation de tabac à rouler des jeunes Canadiens entre 2008 et 2010 et d'examiner les caractéristiques sociodémographiques associées à cette consommation en 2010. MÉTHODOLOGIE: Cette étude utilise des données représentatives recueillies chez des élèves de la 9e à la 12e année dans le cadre des cycles 2008-2009 et 2010-2011 de l'Enquête sur le tabagisme chez les jeunes (ETJ). RÉSULTATS: Parmi les fumeurs, 30,5 % consommaient des cigarettes roulées. Les jeunes bénéficiant d'un revenu disponible de plus de 100 $ par semaine étaient moins nombreux à consommer ce type de produit (rapport de cotes [RC] = 0,49; intervalle de confiance [IC] à 95 % : 0,34 à 0,71). Les consommateurs de tabac à rouler étaient plus nombreux à consommer également de l'alcool (RC=2,01; IC à 95% : 1,09 à 3,72) ou de la marijuana (RC = 2,63; IC à 95 % : 1,73 à 4,01). CONCLUSION: Les cigarettes roulées continuent d'être une solution de rechange abordable pour les jeunes fumeurs. Les programmes de prévention ciblant les consommateurs de cigarettes roulées en milieu scolaire pourraient contribuer à réduire la consommation de ce type de cigarettes.

Minimizing pharmacodynamic interactions of high doses of lacosamide.

OBJECTIVES: To determine whether pharmacodynamic interactions between high doses of lacosamide (400-800 mg/day) and concomitant sodium channel antiepilepsy drugs (AEDs) can be minimized in patients with drug-resistant partial-onset seizures. MATERIALS AND METHODS: Patients were rapidly initiated with high-dose lacosamide (100 mg/week; increases to 400 to 800 mg/day), while simultaneously tapering concomitant sodium channel AEDs. Seizure frequency and side effects were evaluated at six time points: baseline, titration, 3, 6, 9 and 12 months. RESULTS: Twenty-three patients had a baseline median of 4 seizures/month with persisting partial-onset seizures, despite previous treatment with an average of 6.8 AEDs. Mean decreases in monthly seizure frequency were as follows: 3 months 49.9% (P = 0.011), 6 months 55.4% (P = 0.010), 9 months 60.8% (P = 0.002) and 12 months 58.2% (P = 0.011). Most adverse events were mild CNS-related symptoms and occurred transiently only during titration - there was no significant relationship (χ(2) < 1.5, P > 0.1) between lacosamide dose and the presence of side effects at 3, 6, 9 or 12 months. CONCLUSIONS: Drug-resistant patients rapidly titrated to high doses of lacosamide with simultaneous tapering of traditional sodium channel AEDs had marked reduction in CNS-related adverse events compared with patients treated in three previous pivotal trials that used fixed doses of concomitant AEDs.

A review of diversity in the evolution and development of cartilage: the search for the origin of the chondrocyte.

Mammalian cartilage is a complex and developmentally important tissue type. Outside the mammalian lineage, cartilage may persist as an adult tissue, which shows a much wider diversity of histological structure. Tissues similar to vertebrate cartilage are also found within multiple invertebrate lineages, including mollusks, arthropods, and polychaetes, however the relationship of these tissues to vertebrate cartilage is unknown. Detailed molecular analysis of these invertebrate tissues is necessary to assess the degree of homology, if any, of cartilage throughout the metazoans. The purpose of the following review is to introduce readers to this diversity of cartilage and to synthesize the known genetic interactions that give rise to vertebrate cartilage into the format of a gene regulatory network (GRN). This chondrogenesis GRN highlights a large number of transcription factors known to be expressed during chondrogenesis, whose role in this process has yet to be elucidated. Verification and expansion of this initial GRN will assist in the identification of the core set of the genetic interactions necessary for the specification of the vertebrate chondrocyte. This is the necessary first step in allowing detailed comparison of the molecular signature of vertebrate chondrocytes with that of invertebrates with the ultimate goal of understanding the evolutionary origin of this important skeletal cell type.

Fluorescent in situ hybridization reveals multiple expression domains for SpBrn1/2/4 and identifies a unique ectodermal cell type that co-expresses the ParaHox gene SpLox.

Here we report on the expression of two transcription factors previously reported to be involved in endodermal patterning, SpLox and SpBrn1/2/4. We describe three distinct domains of expression of the pou-domain gene SpBrn1/2/4. Endodermal expression of this gene is restricted to the foregut. SpBrn1/2/4 is also expressed in two distinct ectodermal domains: throughout the stomodeal ectoderm, and within cells scattered throughout the ciliated band. The ParaHox gene SpLox is demonstrated to also be expressed in ectodermal bilateral cell pairs in prism and early pluteus stage larvae. Double fluorescent in situ hybridization reveals that these cell pairs co-express both SpLox and SpBrn1/2/4, thus marking a novel cell type within the ciliary band of the sea urchin larvae.

The central nervous system, its cellular organisation and development, in the tadpole larva of the ascidian Ciona intestinalis.

From its numerical composition, the central nervous system (CNS) of the ascidian larva is one of the simplest known nervous systems having a chordate plan. Fewer than 350 cells together constitute a caudal nerve cord, an interposed visceral ganglion containing motor circuits for swimming and, rostrally, an expanded sensory vesicle containing major sensory and interneuron regions of the CNS. Some cells are ependymal, with ciliated surfaces lining the neural canal, while others are clearly either sensory receptors or motoneurons, but most are distinguishable only on cytological grounds. Although reassignments between categories are still being made, there is evidence for determinancy of total cell number. We have made three-dimensional cell maps either from serial semithin sections, or from confocal image stacks of whole-mounted embryos and larvae stained with nuclear markers. Comparisons between the maps of neural tubes in embryos of successive ages, that is, between cells in one map and their progeny in older maps, enable us to follow the line of mitotic descent through successive maps, at least for the caudal neural tube. Details are clear for the lateral cell rows in the neural tube, at least until the latter contains approximately 320 cells, and somewhat for the dorsal cell row, but the ventral row is more complex. In the hatched larva, serial-EM reconstructions of the visceral ganglion reveal two ventrolateral fibre bundles at the caudalmost end, each of 10-12 axons. These tracts include at least five pairs of presumed motor axons running into the caudal nerve cord. Two pairs of axons decussate. Complementing this vertebrate feature in the CNS of the larval form of Ciona, we confirm that synapses form upon the somata and dendrites of its neurons, and that its motor tracts are ventral.

Group cognitive-behavioral therapy and group interpersonal psychotherapy for the nonpurging bulimic individual: a controlled comparison.

This study evaluated the effectiveness of group cognitive-behavioral treatment (CBT) and group interpersonal psychotherapy (IPT) for binge eating. Fifty-six women with nonpurging bulimia were randomly assigned to 1 of 3 groups: CBT, IPT, or a wait-list control (WL). Treatment was administered in small groups that met for 16 weekly sessions. At posttreatment, both group CBT and group IPT treatment conditions showed significant improvement in reducing binge eating, whereas the WL condition did not. Binge eating remained significantly below baseline levels for both treatment conditions at 6-month and 1-year follow-ups. These data support the central role of both eating behavior and interpersonal factors in the understanding and treatment of bulimia.

Inverse ratio ventilation compared with PEEP in adult respiratory failure.

We have compared the cardiorespiratory effects of an inspiratory: expiratory (I:E) ratio of 4:1 with a ratio of 1:2 in 10 adult patients requiring intermittent positive pressure ventilation (IPPV) for acute respiratory insufficiency. Further comparisons were made with IPPV with positive end-expiratory pressure (PEEP) which was adjusted to achieve an equal external end-expiratory volume (EEEV) to that produced by the 4:1 ratio, as determined by respiratory inductive plethysmography, and with an I:E ratio that only changed the EEEV minimally (IRV-min). Percentage pulmonary shunt (Qs/Qt) was reduced equally with PEEP and with the 4:1 I:E ratio but both patterns reduced cardiac output and oxygen delivery. IRV-min also reduced Qs/Qt significantly but had no effect on cardiac output so that oxygen delivery was increased. The dead space to tidal volume ratio (VD/VT) during IPPV-4:1 and IRV-min was reduced significantly when compared with that during IPPV-1:2. The clinical implications of the findings suggest that for some ITU patients, a modest increase in I:E ratio to between 1.1:1 and 1.7:1 may produce better gas exchange without significantly effecting the cardiac output.

Small oxygen analysers.

Analysers using a polarographic electrode had a tendency to react to nitrous oxide, which was considered dangerous with one analyser. However, they had cheaper running costs and a faster response time than the galvanic-cell analysers. These latter analysers were slightly cheaper initially but their sensors were expensive and had a reduced life in the presence of nitrous oxide. Details of accuracy tests have been presented and opinions expressed with regard to the most satisfactory analysers for clinical use.

Paratracheal abscess after tracheostomy.

Mediastinal abscess formation in the paratracheal region is a complication of tracheostomy that has previously been only sparsely reported. We present a case which highlights this complication and illustrates some of the diagnostic difficulties with which it may be associated. In this case septicaemia-developed as a secondary complication and diagnosis of the abscess was dangerously delayed because the radiographic appearance masqueraded as a left upper lobe consolidation and because its rarity led to a low index of suspicion.

Amiloride in primary hyperaldosteronism.

Amiloride is a potassium-sparing diuretic used in spontaneous and diuretic-induced hypokalemia. The effect of amiloride was studied prospectively in 12 patients with primary hyperaldosteronism. Four patients had unilateral adrenal adenomas and eight had bilateral adrenal hyperplasia. All patients were hypertensive and their mean plasma potassium levels were low. Amiloride, 10 to 40 mg daily, was given for 6 mo. Mean plasma potassium levels rose (0.96 mEq/l, P less than 0.001) and remained normal throughout the study without potassium supplementation. Mean blood pressure was lowered by amiloride (22/10 mm Hg, P less than 0.001) but normotension required concomitant antihypertensive therapy in most patients. No significant adverse clinical or laboratory experiences could be directly attributed to amiloride therapy. There was no correlation between the response to therapy and the plasma aldosterone levels, aldosterone secretion rate, or presence of a unilateral adrenal adenoma. Our study demonstrates the efficacy of amiloride in the correction of hypokalemia and amelioration of hypertension in primary hyperaldosteronism.

Importance of potassium in patients with acute myocardial infarction.

The records of 151 patients entering a coronary care unit and subsequently diagnosed as having an acute myocardial infarction were reviewed. The prevalence of hypokalemia, its relationship to diuretic treatment and the development of either ventricular tachycardia or ventricular fibrillation were studied. At admission, 14% of patients were hypokalemic. The presence of hypokalemia was related to previous diuretic therapy. Twenty-three percent of patients receiving diuretics as compared to 7% of patients not taking diuretics had a serum potassium of 3.5 mEq/L or less. Thirty-seven patients experienced either ventricular tachycardia or ventricular fibrillation. The presence of hypokalemia was associated with an increased frequency of both of these arrhythmias. Sixty-seven percent of patients with a serum potassium of less than 3.1 mEq/L had these serious ventricular arrhythmias compared to 40% of patients with a serum potassium between 3.1 and 3.5 mEq/L and 20% of normokalemic patients. The prevalence of premature ventricular beats was not correlated with the presence of hypokalemia. We conclude that hypokalemia is not only a common problem in patients with acute myocardial infarction but a clinically significant factor in the development of life threatening arrhythmias. Primary prevention of hypokalemia and its prompt treatment are indicated in these patients.