Associations of Local Cannabis Control Policies With Harmful Cannabis Exposures Reported to the California Poison Control System.

BACKGROUND: Cannabis exposures reported to the California Poison Control System increased following the initiation of recreational cannabis sales on 1 January 2018 (i.e., "commercialization"). We evaluated whether local cannabis control policies adopted by 2021 were associated with shifts in harmful cannabis exposures. METHODS: Using cannabis control policies collected for all 539 California cities and counties in 2020-2021, we applied a differences-in-differences design with negative binomial regression to test the association of policies with harmful cannabis exposures reported to California Poison Control System (2011-2020), before and after commercialization. We considered three policy categories: bans on storefront recreational retail cannabis businesses, overall restrictiveness, and specific recommended provisions (restricting product types or potency, packaging and labeling restrictions, and server training requirements). RESULTS: Localities that ultimately banned storefront recreational retail cannabis businesses had fewer harmful cannabis exposures for children aged <13 years (rate ratio = 0.82; 95% confidence interval = 0.65, 1.02), but not for people aged >13 years (rate ratio = 0.97; 95% confidence interval = 0.85, 1.11). Of 167 localities ultimately permitting recreational cannabis sales, overall restrictiveness was not associated with harmful cannabis exposures among children aged <13 years, but for people aged >13 years, a 1-standard deviation increase in ultimate restrictiveness was associated with fewer harmful cannabis exposures (rate ratio = 0.93; 95% confidence interval = 0.86, 1.01). For recommended provisions, estimates were generally too imprecise to detect associations with harmful cannabis exposures. CONCLUSION: Bans on storefront retail and other restrictive approaches to regulating recreational cannabis may be associated with fewer harmful cannabis exposures for some age groups following statewide commercialization.

Reported exposures to derived cannabis products in California before and after the 2018 federal reclassification of hemp.

BACKGROUND: As of June 2023, a majority of states had legalized the sale of cannabis, which past research has found to be associated with increased exposures. In 2018, a change in federal policy increased access to cannabidiol (CBD) and derived psychoactive cannabis products, but there has been limited study of reported exposures following this change. METHODS: This observational retrospective study analyzed exposures involving synthetic cannabinoid receptor agonists (SCRAs) and derived cannabis products, including CBD, reported to the California Poison Control System (CPCS) from 2010 to 2022. We focused primarily on potential shifts in reported exposures before and after the implementation of the 2018 Farm Bill, which removed products derived from hemp from the Controlled Substances Act. We reviewed and hand-coded individual call records to assess reported exposures over time and their characteristics, and conducted interrupted time series analysis to assess whether exposure counts changed after policy interventions. RESULTS: Reported CBD exposures significantly increased following the federal reclassification of hemp products. Exposure reports were most common among young children and for edibles. Exposure reports provided limited information about derived psychoactive cannabis products. CONCLUSIONS: Our findings suggest a need for improved data collection regarding derived psychoactive cannabis products, as well as potential public health value in modifying packaging regulations and in providing additional guidance to parents to help prevent CBD exposures.

Exposures to Bleach, Peroxide, Disinfectants, Antimalarials, and Ivermectin Reported to the California Poison Control System Before and During the COVID-19 Pandemic, 2015-2021.

OBJECTIVES: The COVID-19 pandemic led to widespread fear of infection, with many people expanding their use of cleaning products and trying unproven prevention and treatment strategies. We described shifts in reported exposures related to COVID-19 home interventions. METHODS: This study considered suspected toxicity exposures involving household cleaning products (bleach, peroxide, disinfectants), antimalarials (hydroxychloroquine and chloroquine), and ivermectin reported to the California Poison Control System from 2015 through 2021 and assessed trends in exposures by using interrupted time-series analyses. RESULTS: We found a significant increase in exposures reported to the California Poison Control System related to household cleaning products and ivermectin during the COVID-19 pandemic. As of January 1, 2015, the baseline level of reported exposures to household cleaning products was 707.33 per month and was declining at a rate of 1.71 (95% CI, -2.87 to -0.56) per month through February 29, 2020. In March 2020, an increase of 466.57 (95% CI, 328.08-605.07) reported exposures above baseline occurred, after which exposures to cleaning products decreased at a rate of 23.40 (95% CI, -32.48 to -14.32) per month. The number of reported exposures to antimalarials did not change significantly before or during the pandemic. The number of reported ivermectin exposures before December 2020 was initially stable at 14.50 per month and then increased by 2.05 per month through December 2021. CONCLUSIONS: Our observations suggest that while some dangerous home prevention and treatment efforts resolve over time, further interventions may be needed to reduce the public health effects related to attempts to self-treat COVID-19 with ivermectin.

A multi-step approach to the treatment of giant scalp congenital hemangiomas: a report of two cases.

This is a review of two cases of neonatal giant scalp congenital hemangioma. Both patients were treated with propranolol using a similar multi-step approach that included transarterial embolization of the supplying arteries followed by surgical resection of the lesion. In this report, we discuss the treatments, complications, and clinical outcomes of interventions and surgical procedures.

Provably-secure quantum randomness expansion with uncharacterised homodyne detection.

Quantum random number generators (QRNGs) are able to generate numbers that are certifiably random, even to an agent who holds some side information. Such systems typically require that the elements being used are precisely calibrated and validly certified for a credible security analysis. However, this can be experimentally challenging and result in potential side-channels which could compromise the security of the QRNG. In this work, we propose, design and experimentally demonstrate a QRNG protocol that completely removes the calibration requirement for the measurement device. Moreover, our protocol is secure against quantum side information. We also take into account the finite-size effects and remove the independent and identically distributed requirement for the measurement side. More importantly, our QRNG scheme features a simple implementation which uses only standard optical components and are readily implementable on integrated-photonic platforms. To validate the feasibility and practicability of the protocol, we set up a fibre-optical experimental system with a home-made homodyne detector with an effective efficiency of 91.7% at 1550 nm. The system works at a rate of 2.5 MHz, and obtains a net randomness expansion rate of 4.98 kbits/s at 1010 rounds. Our results pave the way for an integrated QRNG with self-testing feature and provable security.

Improving Trendelenburg position effectiveness by varying cardiopulmonary bypass flow.

INTRODUCTION: Trendelenburg position (TP) is used to transport gaseous emboli away from the cerebral region during cardiac surgery. However, TP effectiveness has not been fully considered when combined with varying the cardiopulmonary bypass (CPB) flow. This study simulated the supine and TP at different pump flows and assessed the trapped emboli and embolic load entering the aortic arch branch arteries (AABA). METHODS: A computational fluid dynamics (CFD) approach used a centrally cannulated adult patient-specific aorta model replicating a CPB circuit. Air emboli of 0.1 mm, 0.5 mm, and 1.0 mm (n = 700 each) were injected into the aorta placed in the supine position (0°) and the TP (-20°) at 2 L/min and 5 L/min. The number of emboli entering the AABA were compared. An aortic phantom flow experiment was performed to validate air bubble behaviour. RESULTS: TP at 5 L/min had the lowest 0.1 mm mean (±SD) embolic load compared to the supine 2 L/min (55.3 ± 30.8 vs 64.3 ± 35.4). For both the supine and TP, the lower flow of 2 L/min had the highest number of simulated trapped emboli in higher elevated regions than at 5 L/min (541 ± 185 and 548 ± 191 vs 520 ± 159 and 512 ± 174), respectively. The flow experiment demonstrated that 2 L/min promoted bubble coalescence and high amounts of trapped emboli and 5 L/min transported air emboli away from the AABA. CONCLUSIONS: TP effectiveness was improved by using CPB flow to manage air emboli. These results provide insights for predicting emboli behaviour and improving emboli de-airing procedures.

Effect of aortic cannulation depth on air emboli transport during cardiopulmonary bypass: A computational study.

INTRODUCTION: Varying the insertion depth of the aortic cannula during cardiopulmonary bypass (CPB) has been investigated as a strategy to mitigate cerebral emboli, yet its effectiveness associated with CPB flow is not fully understood. We compared different arterial cannula insertion depths and pump flow influencing air microemboli entering the aortic arch branch arteries (AABA). METHODS: A computational approach used a patient-specific aorta model to evaluate four cannula locations at (1) proximal arch, (2) mid arch, (3) distal arch, and (4) descending aorta. We injected 0.1 mm microemboli (N=720) at 2 and 5 L/min and assessed the embolic load and the particle averaged transit times ( entering the AABA. RESULTS: Location 4 had the lowest embolic load (2 L/min: N= 63) and (5 L/min: N= 54) compared to locations 1 to 3 in the range of (N= 118 to 116 at 2 L/min:) and (N= 92 to 146 at 5 L/min). There was no significant difference between 2 L/min and 5 L/min (p = 0.31), despite 5 L/min attaining a lower mean (±standard deviation) than 2 L/min (38.0±23.4 vs 44.5±21.1), respectively. Progressing from location 1 to 4, increased 3.11s -7.40 s at 2 L/min and 1.81s -4.18s at 5 L/min. CONCLUSION: It was demonstrated that the elongated cannula insertion length resulted in lower embolic loads, particularly at a higher flow rate. The numerical results suggest that CPB management could combine active flow variation with improving cannula performance and provide a foundation for a future experimental and clinical investigation to reduce surgical cerebral air microemboli.

EEG analysis and classification based on cardinal spline empirical mode decomposition and synchrony features.

Dementia is a major cause of disability and dependency among older adults. Diagnosis is most effective at an early stage of the disease, as patients can start early treatment to delay progressive cognitive decline. While other diagnostic methods for dementia are available, electroencephalography (EEG) is noninvasive, more accessible, and less complicated than other biomarker measurements. Moreover, it may be orders of magnitude less expensive, thereby offering the possibility of low-cost mass screening. This paper presents a novel digital signal processing method called cardinal spline empirical mode decomposition (CS-EMD) for EEG processing. This new method uses a different signal envelope interpolation algorithm to separate EEG signals into constituent components, called intrinsic mode functions (IMFs), with better signal decomposition properties than classical empirical mode decomposition (EMD). The IMFs obtained from the new method are then used to compute longitudinal and transversal synchrony measures, which are explored as features for healthy and dementia classification using a support vector machine (SVM). The performance of the proposed method is studied on a publicly available EEG dataset. The results show that using multiple synchrony measures of both longitudinal and transversal EEG channels on five IMFs produces the best classification result of 90% accuracy, 96.67% specificity, 83.33% sensitivity, and 96.15% precision, outperforming the classical EMD method and various other approaches. This new, data-driven CS-EMD method shows good potential as a dementia screening tool. CS-EMD may also be applied in processing other nonlinear and nonstationary biosignals.

Lineage tracing reveals the phylodynamics, plasticity, and paths of tumor evolution.

Tumor evolution is driven by the progressive acquisition of genetic and epigenetic alterations that enable uncontrolled growth and expansion to neighboring and distal tissues. The study of phylogenetic relationships between cancer cells provides key insights into these processes. Here, we introduced an evolving lineage-tracing system with a single-cell RNA-seq readout into a mouse model of Kras;Trp53(KP)-driven lung adenocarcinoma and tracked tumor evolution from single-transformed cells to metastatic tumors at unprecedented resolution. We found that the loss of the initial, stable alveolar-type2-like state was accompanied by a transient increase in plasticity. This was followed by the adoption of distinct transcriptional programs that enable rapid expansion and, ultimately, clonal sweep of stable subclones capable of metastasizing. Finally, tumors develop through stereotypical evolutionary trajectories, and perturbing additional tumor suppressors accelerates progression by creating novel trajectories. Our study elucidates the hierarchical nature of tumor evolution and, more broadly, enables in-depth studies of tumor progression.

COVID-19 vaccine acceptance and hesitancy among ethnic minorities in Hong Kong.

Ethnic minorities account for 8% of the Hong Kong population, most are Filipino and Indonesian domestic helpers taking care of children and the elderly. To understand the COVID-19 vaccination rates and factors associated with vaccine acceptance of ethnic minorities, we performed a cross-sectional questionnaire study recruiting Hong Kong ethnic minorities aged ≥18 years between 1 July and 18 July 2021 in public areas. Demographics, knowledge about COVID-19, vaccination status, intention and reasons to receive the vaccine, and planning to be re-vaccinated were analyzed. Continuous and categorical variables were compared using unpaired t-test and Chi-square test, respectively. Potential confounders were adjusted using multiple logistic regression. 2,012 ethnic minorities participated, with a mean age of 39 years, of which 97.6% were female, 79.5% were Filipino, and 17.5% were Indonesian. 80.6% of participants were categorized as vaccine acceptance, and 69.2% were willing to be re-vaccinated. There were significantly more Filipinos than Indonesians in the vaccine acceptance group (p < .001). Subjects in the vaccine acceptance group were more likely to have higher education (p < .001), a higher COVID-19 knowledge score (p < .001), received information from the Government website (p = .003) and not from their friends or family members (p = .02), and were more confident in judging the accuracy of the information (p < .001). Logistic regression showed the mean knowledge score (ß = 3.07, p < .001) and receiving information from official Government websites (adjusted OR = 1.37, p = .03) were significant factors that positively influenced vaccine acceptance. The Hong Kong Government should improve COVID-19 vaccination acceptance among ethnic minorities through public education using official channels.

Changes in California cannabis exposures following recreational legalization and the COVID-19 pandemic.

INTRODUCTION: Since 2012, eighteen states and the District of Columbia have legalized recreational cannabis. Past research suggests this policy change is associated with increased cannabis exposures however this has not yet been studied in California, despite its status as the world's largest legal cannabis market. METHODS: This observational, retrospective study analyzed trends in cannabis exposures reported to the California Poison Control System (CPCS) from 2010 to 2020. We assessed shifts in exposures before and after the legalization of recreational cannabis in November 2016, the establishment of recreational retail sales in January 2018, and the institution of a statewide shelter-in-place order due to the COVID-19 pandemic in March 2020 using interrupted time-series analysis and reviewed all records to identify specific products associated with exposures. RESULTS: Between 2010 and 2020 edible exposures increased from near zero to 79% of exposures in 2020. Cannabis exposures significantly increased following recreational legalization in 2016 (by an estimated 2.07 exposures per month [CI: 0.60, 3.55]; p < 0.01) and initiation of retail sales in 2018 (0.85 [CI: 0.12, 1.58]; p < 0.05). There was no significant change in cannabis exposures following the first shelter-in-place order of the COVID-19 pandemic (1.59 [CI: -1.61, 3.68]; p = 0.43). Cannabis exposures for those thirteen and under increased significantly both after recreational legalization (1.04 [CI: 0.38, 1.70]) and after the opening of the retail sales market (0.73 [CI: 0.34, 1.12]), but not following the shelter-in-place order (1.59 [CI: -1.61, 3.68]), nor was there a significant change for those older than thirteen. CONCLUSIONS: Our findings suggest that cannabis legalization is linked to increased exposures, particularly for products such as gummies and candy edibles among children under the age of thirteen. Clinicians should be aware of these risks and communicate them to patients, and policymakers should consider stronger regulations on packaging to reduce these exposures.Key pointsQuestion: How have cannabis exposures changed following legalization of recreational use, the opening of the recreational retail sales market, and the institution of shelter-in-place orders during the COVID-19 pandemic?Findings: In this retrospective review of 10,757 cases reported to the California Poison Control System (CPCS) between 2010 and 2020, exposures increased significantly after the legalization of recreational cannabis use and the opening of the recreational retail sales market, particularly among children, who primarily consumed candies and gummies.Meaning: Stronger regulation of cannabis edibles that mimic other products is warranted to decrease exposures among children.

Pattern and determinants of alcohol and tobacco co-use and its relationship with smoking cessation in Hong Kong.

INTRODUCTION: Alcohol and tobacco are often used together. Studies have shown that some biological factors contribute to the concurrent use of alcohol and nicotine. There have been comparatively few studies that document the concurrent prevalence and correlates of alcohol and tobacco use among adults. A better understanding of the smokers who also drink is needed to help them to quit smoking. METHODS: A retrospective case review study on smokers who voluntarily joined our service in 2014-2017 was conducted. Characteristics of tobacco users only, and alcohol and tobacco co-users were reviewed. The quit rate of smoking related to alcohol use was analyzed. Participants were contacted by phone at week 26 and 52 to ascertain smoking status and abstinence. RESULTS: There were 4602 alcohol and tobacco co-users and 2732 tobacco only users. Co-users had higher education level and better income than tobacco only users. In all, 52.24% of co-users were aged 21-40 years. For the alcohol users, their mean AUDIT score was only 6.17 (SD: 5.67). Multivariate analysis showed that age and gender were associated with co-use while high personal income had lower odds of co-use. Quit rate decreased as the AUDIT score increased. Those who had binge drinking more than once a month had lower quit rate compared with binge drinking less than once a month at week 26 (34.2% vs 43.19%, p<0.0001). CONCLUSIONS: Alcohol and tobacco co-users should acknowledge alcohol-tobacco interactions to reduce alcohol use and prevent smoking relapse. Healthcare providers should screen for alcohol use in smoking cessation interventions.

California Poison Control System Implementation of a Novel Hotline to Treat Patients with Opioid Use Disorder.

INTRODUCTION: In response to the opioid epidemic, California state officials sought to fund a variety of projects aimed at reducing opioid-related deaths. We describe the California Poison Control System's (CPCS) successful effort in integrating itself into the state's public health response to the opioid epidemic and describe poison control center staff attitudes and perceptions regarding the role of poison control centers at treating opioid withdrawal and addiction. METHODS: The CPCS created a leadership team and a separate 24/7 hotline, called the CPCS-Bridge line, to field calls from frontline health care providers interested in initiating medications for opioid use disorder for their patients. The implementation process also included training of all CPCS staff. In addition, the leadership team conducted an anonymous survey study to analyze attitudes and perceptions of poison center staff on the role of the poison center in the management of opioid use disorder. Descriptive statistics were used to characterize the data. RESULTS: Calls to the new hotline increased over time, along with CPCS-initiated outreach and advertisement. A majority of questions received by the hotline were related to uncomplicated buprenorphine starts in special populations. A pre-training survey was completed by 27 (58%) of CPCS specialists, many of whom had no prior experience treating patients with opioid use disorder. Only one specialist (2%) did not believe that poison centers should play a role in opioid addiction. CONCLUSIONS: The California Poison Control System successfully created a hotline to assist frontline health care providers in treating patients with opioid use disorder and highlight the critical role of poison centers in the public health domain. Increased federal funding to poison centers is likely to be mutually beneficial to all parties involved.

Characteristics of Chinese smokers with psychotic disorders and their predictors on smoking cessation in Hong Kong.

INTRODUCTION: People with psychotic disorders are associated with high prevalence of cigarette smoking and prevalence rates. Studies show that many smokers with psychotic disorders would like to stop smoking, yet the abstinence rate among them is low. Despite this significant public health problem, few studies have examined the characteristics of this group of smokers and the predictors of smoking cessation. METHODS: This is a retrospective chart review study. Case records of smokers who attended our smoking cessation clinic with and without psychotic disorders were reviewed. The outcome measure was self-reported 7-day point prevalence abstinence rate at week 26. The basic demographic and biosocial characteristics of these smokers were analyzed. RESULTS: A total of 3671 case records were reviewed and 155 smokers with psychosis were identified. The independent predictors of smoking abstinence at week 26 were to improve performance in exercise and sports, greater confidence of quitting, and greater number of counselling sessions. The 7-day point prevalence abstinence rate was 22.6% at 26 weeks. CONCLUSIONS: This study has demonstrated that many smokers with psychosis are able to quit smoking even with NRT and counselling and without use of oral medications. Health professionals need to pay greater attention to tobacco use by individuals with mental disorders. Every effort should be given to enhance their motivation, build up their confidence and to provide adequate counselling sessions.

Aortic cannula orientation and flow impacts embolic trajectories: computational cardiopulmonary bypass.

INTRODUCTION: Emboli events are associated with the aortic cannula insertion and final position in the ascending aorta. However, the impact of subtle changes in aortic cannula movement and flow influencing embolic transport throughout the aortic arch is not well understood. The present study evaluated the aortic cannula's outflow and orientation effect on emboli entering the aortic branch arteries. METHODS: A simplified aortic computational model was anteriorly cannulated in the distal ascending aorta with a 21-French straight aortic cannula, and two orientations were analysed by injecting gaseous and solid emboli at pump flows 2, 3 and 5 L/minute. The first aortic cannula orientation (forward flow cannula) was directed towards the lesser curvature. The second aortic cannula orientation (rear flow cannula) was tilted slightly backwards by 15°, providing flow in the retrograde direction. RESULTS: Forward flow cannula produced a primary arch flow, whereas rear flow cannula produced a secondary arch flow resulting in four times longer emboli arch resident times than forward flow cannula. The rear flow cannula had the highest percentage of gaseous emboli entering the brachiocephalic artery of 8%, 12% and 36% (at 2, 3 and 5 L/minute, respectively). Rear flow cannula provided a positive aortic branch arterial flow at all pump flows, whereas at forward flow cannula, the brachiocephalic artery experienced retrograde flows of -1.0% (3 L/minute) and -4.0% (5 L/minute), with the left common carotid -0.23% (5 L/minute). No significant number of solid emboli entered the aortic branch arteries. CONCLUSION: This numerical study illustrated distinct trajectory behaviours between gaseous and solid emboli where slight changes in aortic cannula orientation influenced idealised emboli direction with higher pump flows magnifying the effects.

Parthenolide Covalently Targets and Inhibits Focal Adhesion Kinase in Breast Cancer Cells.

Parthenolide, a natural product from the feverfew plant and member of the large family of sesquiterpene lactones, exerts multiple biological and therapeutic activities including anti-inflammatory and anti-cancer effects. Here, we further study the parthenolide mechanism of action using activity-based protein profiling-based chemoproteomic platforms to map additional covalent targets engaged by parthenolide in human breast cancer cells. We find that parthenolide, as well as other related exocyclic methylene lactone-containing sesquiterpenes, covalently modify cysteine 427 of focal adhesion kinase 1 (FAK1), leading to impairment of FAK1-dependent signaling pathways and breast cancer cell proliferation, survival, and motility. These studies reveal a functional target exploited by members of a large family of anti-cancer natural products.

A case report of a rare, spontaneous external jugular vein aneurysm.

INTRODUCTION: Compared to arterial aneurysms, venous pseudoaneurysms are rare and even more rare are external jugular vein aneurysms (EJV). To our knowledge, there are less than 10 well-documented cases of EJV aneurysms accessible. PRESENTATION OF CASE: Our patient is a 75 year old hispanic female who noticed a painless right neck mass two months prior. Ultrasound confirmed a cystic mass of unknown etiology containing doppler flow. Excisional biopsy revealed an EJV aneurysm with pathologic results of: blood, calcified debris, and a vessel wall consistent with EJV pseudoaneurysm. DISCUSSION: EJV aneurysms are clinically rare compared to IJV aneurysms. Recent trauma, cardiovascular disease and age are reported to be the highest significant clinical risk factors in the formation of jugular vein aneurism (JVA). The absence of trauma in our patient is noteworthy because it eliminates a direct contributor to a normally low-pressure vessel. CONCLUSIONS: Despite their rarity, spontaneous EJV aneurisms should be included in the differential of the elderly hypertensive patient who is presenting with a painless mass of the lateral neck that has cystic appearance and ultrasound findings of doppler flow.

Pilot study of a 3-day residential treatment for smoking cessation in Hong Kong.

INTRODUCTION: The Tung Wah Group of Hospitals Integrated Centre on Smoking Cessation has been providing free smoking cessation services since 2009. The average quit rate from 2009 to 2014 was 37%. In order to boost the quite rate, we have implemented a residential treatment program for smokers who volunteered to participate. Having run the program for two years, we conducted a retrospective cohort study to evaluate its effectiveness. METHODS: We recruited the participants who had failed previous quit attempts and who came to seek our smoking cessation services. A 3-day residential program of activities were arranged for our participants. Intensive individual and group counseling was provided. Pharmacotherapy was also provided to alleviate withdrawal symptoms. This was followed by our usual treatment and follow-up program. Self-reported 7-day point prevalence abstinence rate at 26 weeks based on intention-to-treat (ITT) analysis was assessed. RESULTS: A total of 40 clients volunteered to join the program, age 26 to 65 years old with a mean of 44.1 years. There were 25 (62.5%) males and 15 (37.5%) females. The quit rate at 26 weeks was 57.5%. Smokers older than 43 years, having cohabiting smokers, and smoking for more than 28 years, were more likely to quit and this was statistically significant. CONCLUSIONS: This pilot study demonstrated that a 3-day residential program is effective in helping addicted smokers who volunteer to quit smoking and is cost effective compared to longer residential programs.

Sighting ocular dominance magnitude varies with test distance.

BACKGROUND: Ocular dominance can be defined as the preference of an individual for viewing with one eye over the other for particular visual tasks. It is relevant to monovision contact lens wear, cataract surgery and sports vision. Clinically, the measurement of ocular dominance is typically done at an arbitrary distance using a sighting test, such as the hole-in-card method that has a binary outcome. We investigated the effect of test distance on ocular dominance measured using a binocular sighting test that provided a continuous measurement of dominance. METHODS: Ten participants with normal binocular vision took part in this study. Their binocular sighting ocular dominance and phorias were measured at one, two, four, eight and 10 metres. During the dominance tests participants made a binocular alignment judgment and then were asked to indicate the relative alignment of each eye using a visual analogue scale as a reference. RESULTS: Eight participants had strong ocular dominance (five right, three left). For these participants, there was a significant increase in the magnitude of dominance with increasing test distance (p < 0.001). This could not be fully explained by changes in convergence demand. Two participants showed very weak ocular dominance across all test distances (p > 0.05), despite changes in convergence demand. CONCLUSION: When ocular dominance is present, its magnitude varies significantly with test distance. This has significant implications for the accurate measurement of ocular dominance in the clinic and may reflect the neural processes that influence eye preference.

Cannabis Intoxication Case Series: The Dangers of Edibles Containing Tetrahydrocannabinol.

STUDY OBJECTIVE: Cannabis and its principal active constituent, Δ9-tetrahydrocannabinol (THC), are increasingly available as edibles resembling commercially available food products. In this case series, we describe a population of predominantly pediatric patients who were inadvertently exposed to a THC-containing product in San Francisco. METHODS: Twelve children and 9 adults were identified, with 16 patients having detectable serum THC and THC metabolites. All patients presented to hospitals with a variety of constitutional symptoms and all were discharged home within 12 hours. RESULTS: In general, pediatric patients had more severe symptoms and longer hospital length of stay, and, uniquely, a majority presented with leukocytosis and elevated lactic acid levels. CONCLUSION: We recommend that efforts be made to increase general public awareness in regard to the potential hazards of THC-containing edibles resembling commercially available food products.