The role of sleep in the link between cannabis use and memory function: evidence from a cross-sectional study.

Background: It is known that cannabis use affects memory and sleep problems independently. However, to date, how memory and sleep problems may interact as a result of cannabis use remains unknown.Objectives: We performed a secondary analysis of existing data to determine whether sleep quality mediates the association between cannabis use and memory and whether sex moderated these effects.Methods: A total of 141 adults with cannabis use disorder (CUD) (83 men) and 87 without CUD (39 men) participated in this study. Outcome measures included self-reported sleep problems from the past 7 days (Marijuana Withdrawal Checklist), learning and memory performance via the short visual object learning task (sVOLT), short visual object learning task delayed (sVOLTd), and verbal memory via the N-back. Bootstrapped mediation and moderated mediation analyses were run to test if sleep quality mediated the association between cannabis use and memory outcomes and whether sex moderated these effects, respectively.Results: Sleep quality mediated the effect of group (i.e. adults with and without CUD) on sVOLT efficiency scores (indirect effect ß = -.08, 95% CI [-0.14, -0.04]) and sVOLTd efficiency scores (indirect effect ß = -.09, 95% CI [-0.14, -0.04]), where greater sleep difficulties was associated with poorer memory performance (decreased efficiency scores). Sex did not moderate these relationships.Conclusion: These initial findings of a mediating role of sleep in the association between CUD and visual learning memory highlight potential critical downstream effects of disrupted sleep in those with CUD and suggest the importance of investigating sleep in CUD.

Resting state functional connectivity in dependent cannabis users: The moderating role of cannabis attitudes.

BACKGROUND: The global increase in lenient cannabis policy has been paralleled by reduced harm perception, which has been associated with cannabis use initiation and persistent use. However, it is unclear how cannabis attitudes might affect the brain processes underlying cannabis use. METHODS: Resting state functional connectivity (RSFC) within and between the executive control network (ECN), salience network (SN), and default mode network (DMN) was assessed in 110 near-daily cannabis users with cannabis use disorder (CUD) and 79 controls from The Netherlands and Texas, USA. Participants completed a questionnaire assessing the perceived benefits and harms of cannabis use from their personal, friends-family's, and country-state's perspectives and reported on their cannabis use (gram/week), CUD severity, and cannabis-related problems. RESULTS: RSFC within the dorsal SN was lower in cannabis users than controls, while no group differences in between-network RSFC were observed. Furthermore, heavier cannabis use was associated with lower dorsal SN RSFC in the cannabis group. Perceived benefits and harms of cannabis - from personal, friends-family's, and country-state's perspectives - moderated associations of cannabis use, CUD severity, and cannabis use-related problems with within-network RSFC of the SN, ECN, and DMN. Personal perceived benefits and country-state perceived harms moderated the association between CUD severity and RSFC between the ventral and dorsal DMN. CONCLUSIONS: This study highlights the importance of considering individual differences in the perceived harms and benefits of cannabis use as a factor in the associations between brain functioning and cannabis use, CUD severity, and cannabis use-related problems.

Engagement in HIV Care Among New York City Transgender Women of Color: Findings from the Peer-Led, TWEET Intervention, a SPNS Trans Women of Color Initiative.

Transgender women (TW) have higher HIV prevalence rates than cisgender (i.e., non-transgender) women. However, utilization of healthcare for transgender people in the U.S. is low. As part of a multisite initiative to facilitate entry and retention in HIV care for TW of color, we compared health outcomes between participants who became Peer Leaders and those who did not. From 2013 to 2016, 163 New York City, mostly Latina, TW enrolled in the Transgender Women Engagement and Entry to Care Project (TWEET). The TWEET intervention included peer-led, group-based educational sessions called Transgender Leader-Teach Back; 39% completed Peer Leadership requirements. Comparing pre-post change by Peer Leader status, Peer Leaders had a significant decrease in viral load and significant increase in CD4 at the last HIV care visit compared to the first. In multivariable logistic regression, predictors associated with Peer Leadership included having at least some college education, being in a relationship, stable housing, receiving legal assistance for political asylum, and having two or more HIV care visits during the intervention. Findings suggest that, for trans women who have completed at least secondary school education, participating in a peer-led intervention can lead to improved HIV care engagement. Understanding which program components lead to becoming a Peer Leader, and how to better engage non-Peer Leaders, are important next steps.

Methods for Collection of Participant-aided Sociograms for the Study of Social, Sexual and Substance-using Networks Among Young Men Who Have Sex with Men.

In this study, we adapted and tested a participant-aided sociogram approach for the study of the social, sexual, and substance use networks of young men who have sex with men (YMSM); a population of increasing and disproportionate risk of HIV infection. We used a combination of two interviewer-administered procedures: completion of a pre-numbered list form to enumerate alters and to capture alter attributes; and a participant-aided sociogram to capture respondent report of interactions between alters on an erasable whiteboard. We followed the collection of alter interactions via the sociogram with a traditional matrix-based tie elicitation approach for a sub-sample of respondents for comparison purposes. Digital photographs of each network drawn on the whiteboard serve as the raw data for entry into a database in which group interactions are stored. Visual feedback of the network was created at the point of data entry, using NetDraw network visualization software for comparison to the network structure elicited via the sociogram. In a sample of 175 YMSM, we found this approach to be feasible and reliable, with high rates of participation among those eligible for the study and substantial agreement between the participant-aided sociogram in comparison to a traditional matrix-based approach. We believe that key strengths of this approach are the engagement and maintenance of participant attention and reduction of participant burden for alter tie elicitation. A key weakness is the challenge of entry of interview-based list form and sociogram data into the database. Our experience suggests that this approach to data collection is feasible and particularly appropriate for an adolescent and young adult population. This builds on and advances visualization-based approaches to social network data collection.

Researching special populations: retention of Latino gay and bisexual men and transgender persons in longitudinal health research.

Few studies have sought to assess predictors of retention of racial/ethnic or sexual minorities in longitudinal health research. The purpose of this study is to investigate predictors of retention of Latino gay and bisexual men and transgender (GBT) research participants after the baseline interview. Data come from a sample of 643 Latino GBT individuals in two cities (Chicago and San Francisco). We assessed potential predictors of retention (operationalized as successful re-contact) using binary logistic regression of retention on five factors (sociodemographic/health, residential stability, acculturation/attachment to the United States, gay community attachment/stigmatization and research process/design). Our overall follow-up rate was 83 and 80% at 3 and 6 months, respectively. We found that traditional factors (e.g. education, income) were not associated with retention among Latino GBT. The strongest predictors of successful retention were the number of pieces of contact information provided by participants and city of residence (San Francisco). Furthermore, successful methods of contact (i.e. telephone, email) varied by city. We conclude that a largely immigrant urban population of Latino GBT individuals can be successfully followed in longitudinal research. The strong relationship between study design variables and successful retention indicates that collection of thorough contact information is vital to successful follow-up with this population.

Three quantitative approaches to the diagnosis of abdominal pain in children: practical applications of decision theory.

BACKGROUND/PURPOSE: The authors compared 3 quantitative methods for assisting clinicians in the differential diagnosis of abdominal pain in children, where the most common important endpoint is whether the patient has appendicitis. Pretest probability in different age and sex groups were determined to perform Bayesian analysis, binary logistic regression was used to determine which variables were statistically significantly likely to contribute to a diagnosis, and recursive partitioning was used to build decision trees with quantitative endpoints. METHODS: The records of all children (1,208) seen at a large urban emergency department (ED) with a chief complaint of abdominal pain were immediately reviewed retrospectively (24 to 72 hours after the encounter). Attempts were made to contact all the patients' families to determine an accurate final diagnosis. A total of 1,008 (83%) families were contacted. Data were analyzed by calculation of the posttest probability, recursive partitioning, and binary logistic regression. RESULTS: In all groups the most common diagnosis was abdominal pain (ICD-9 Code 789). After this, however, the order of the most common final diagnoses for abdominal pain varied significantly. The entire group had a pretest probability of appendicitis of 0.06. This varied with age and sex from 0.02 in boys 2 to 5 years old to 0.16 in boys older than 12 years. In boys age 5 to 12, recursive partitioning and binary logistic regression agreed on guarding and anorexia as important variables. Guarding and tenderness were important in girls age 5 to 12. In boys age greater than 12, both agreed on guarding and anorexia. Using sensitivities and specificities from the literature, computed tomography improved the posttest probability for the group from.06 to.33; ultrasound improved it from.06 to.48; and barium enema improved it from.06 to.58. CONCLUSIONS: Knowing the pretest probabilities in a specific population allows the physician to evaluate the likely diagnoses first. Other quantitative methods can help judge how much importance a certain criterion should have in the decision making and how much a particular test is likely to influence the probability of a correct diagnosis. It now should be possible to make these sophisticated quantitative methods readily available to clinicians via the computer.

Ultrasound examination of ankle injuries in children.

Fourteen children with ankle injuries, an open tibia and fibula physis, and negative radiographs had ultrasonography of their injured ankles. Five had an anterior talofibular ligament injury and five had an anterior tibiofibular ligament injury. Four had normal ultrasound examinations. Only two had a physeal injury, both of which were associated with a ligament injury. Eleven children had only lateral ankle tenderness. Ultrasound of these 11 revealed ligamentous injuries, normal examinations, and the two physeal injuries. Ligamentous injury was not associated with other tenderness patterns.

Use of computerized tomography and chest x-rays in evaluating efficacy of aerosolized recombinant human DNase in cystic fibrosis patients younger than age 5 years: a preliminary study.

The aim of this study was to evaluate the ability of high-resolution computerized tomography (HRCT) of the chest and chest x-rays (CXR) to determine efficacy of inhaled recombinant human DNase (rhDNase) in cystic fibrosis (CF) patients younger than 5 years of age. A randomized, double-blind, placebo-controlled pilot study of 12 patients with CF younger than 5 years of age, attending the University of Michigan Cystic Fibrosis Center (Ann Arbor, MI) was conducted. The changes in the HRCT and CXR score from baseline to day 100 of therapy were assessed using a previously validated scoring system. The mean changes of HRCT scores between the rhDNase and placebo groups were found to be significant at the 95% level, with mean change +/- SE mean of - 1.00 +/- 0.53 and 0.58 +/- 0.24 for rhDNase and placebo groups, respectively (P = 0.02). The difference in CXR score was not significant between the two groups. An analysis was performed to relate HRCT subscores to CXR score; only thickening of the intra-interlobular septae was significantly correlated with the total CXR score (r = - 0.7, P < 0.01). There was improvement in the parents' assessments of the patients' well-being, with improvement in physical activity, decreased cough, sleep quality, and appetite in those subjects receiving rhDNase. We conclude that the administration of rhDNase was associated with improvement in the HRCT scan in CF patients younger than 5 years of age. Findings indicate that HRCT of the chest is useful and sensitive in studying responses to therapy in patients with CF lung disease. To our knowledge, this is the first report of the use of HRCT to assess the effectiveness of a therapeutic modality in so young a CF patient population.

The nomenclature and sectional imaging anatomy III: capsular membranes and minor spinal ligaments.

This paper is the third in a series of three that organizes the complex anatomy of the cervical, thoracic, and lumbar spinal ligaments. It describes and color-codes the anatomy and nomenclature of the capsular membranes and minor spinal ligaments. The first two articles describe the dorsal and ventral ligaments, respectively.

The nomenclature and sectional imaging anatomy II: ventral spinal ligaments.

This paper is the second in a series of three that organizes the complex anatomy of the cervical, thoracic, and lumbar spinal ligaments. It describes and colorcodes the anatomy and nomenclature of the ventral ligaments. A prior article has described the dorsal ligaments, and a future article will illustrate the capsular joints and minor spinal ligaments.

Cervical spine standards for flexion radiograph interspinous distance ratios in children.

RATIONALE AND OBJECTIVES: The purpose of this study was to quantitate the interspinous distances in a group of children as they underwent flexion during lateral radiography. MATERIALS AND METHODS: The cases of 59 children with minor trauma who underwent lateral flexion radiography were studied retrospectively. Measurements of each cervical interspinous distance and anteroposterior diameter of the adjacent body were used to calculate a ratio of interspinous distance to vertebral body diameter at each level. Linear regression analyses of each ratio to patient age were performed, and means and standard deviations of the ratios at each level were calculated. RESULTS: The ratios did not correlate in a statistically significant manner at any level with age. Therefore, data from all 59 children were used to calculate the mean and standard deviation at each cervical level. Most children with severe ligamentous injury who were considered for fusion had interspinous ratios greater than 2 standard deviations above the mean for the control group. CONCLUSION: Standards for interspinous distances during flexion by children are presented. These standards may prove to be helpful in the evaluation of children for cervical ligamentous injury.

Equine dental disease part 4: a long-term study of 400 cases: apical infections of cheek teeth.

Of 400 horses referred because of equine dental disease, 162 suffered from primary apical infections of their cheek teeth (CT), including 92 with maxillary CT infections and 70 with mandibular CT infections. Maxillary swellings and sinus tracts were more common (82 and 26% incidence, respectively) with infections of the rostral 3 maxillary CT, than with infections of the caudal 3 maxillary CT (39 and 5% incidence, respectively). Nasal discharge was more commonly present with caudal (95%) than rostral (23%) maxillary CT infections. Mandibular CT apical infections commonly had mandibular swellings (91%) and mandibular sinus tracts (59%) and these infections were closely related to eruption of the affected CT. A variety of treatments, including medical treatment, apical curettage, repulsion and oral extraction of affected teeth were utilised in these cases, with oral extraction appearing to be most satisfactory. Infections of caudal maxillary CT with a secondary paranasal sinusitis were most refractory to treatment, with a complete response to the initial treatment achieved in just 33% of these cases. Most other cases responded fully to their initial treatment. The long-term response to treatment was good in most cases.

The nomenclature and sectional imaging anatomy I: dorsal spinal ligaments.

This article is the first in a series of three that organizes the complex anatomy of the cervical, thoracic, and lumbar spinal ligaments. It describes and color-codes the anatomy and nomenclature of the dorsal ligaments. The following articles will describe the ventral ligaments, and the capsular membranes and minor ligaments.

Equine dental disease. Part 3: A long-term study of 400 cases: disorders of wear, traumatic damage and idiopathic fractures, tumours and miscellaneous disorders of the cheek teeth.

Of 400 horses referred because of dental disorders, 349 cases were diagnosed as suffering from primary disorders of their cheek teeth. Details of 104 of these cases are presented, including 44 cases with abnormalities of wear, 26 cases with traumatic damage, 24 cases with idiopathic fractures and 10 cases with miscellaneous cheek teeth disorders including oral tumours. The long-term response to treatment was excellent in most cases, even in cases with residual secondary periodontal disease.

Equine dental disease part 2: a long-term study of 400 cases: disorders of development and eruption and variations in position of the cheek teeth.

Of 400 referred horses with dental disorders, 349 cases suffered from primary disorders of their cheek teeth, ninety of these from disorders of development or eruption, or displacements. These included 20 cases with rostral maxillary and caudal mandibular cheek teeth overgrowths, 16 with diastemata, 15 with grossly enlarged mandibular 'eruption cysts', 4 with grossly enlarged maxillary cheek teeth 'eruption cysts', 10 cases with supernumerary cheek teeth and 23 cases with displaced cheek teeth. These displacements were believed to be developmental in 16 cases and acquired in the remaining 7 cases. Long-term response to treatments, that included removal of overgrowths and extraction of teeth with deep secondary periodontal disease was excellent for most disorders except diastemata.

Equine dental disease part 1: a long-term study of 400 cases: disorders of incisor, canine and first premolar teeth.

A review of 400 horses referred because of dental disorders showed 44 cases to suffer from primary disorders of their incisors and 11 from canine or 1st premolar teeth disorders. The remaining 345 horses suffered from primary disorders of the cheek teeth. Disorders of incisors included traumatic damage to teeth and their supporting bones, retained deciduous, displaced and supernumerary incisors; brachygnathia and abnormalities of wear, with most of the latter disorders being secondary to primary disorders of the cheek teeth Only 3 cases of apical infection of incisors were recognised. Most cases of fractured incisors responded well to conservative therapy. Retained deciduous incisors were extracted, but most cases with supernumerary and displaced incisors, or brachygnathia were treated conservatively. Most disorders of the canine and 1st premolar were developmental displacements that caused bitting problems (abnormalities of head movement associated with the bit), and these cases responded well to extraction of the displaced teeth.

Facet coverage in children on flexion lateral cervical radiographs.

STUDY DESIGN: This radiographic study was designed to attempt to develop standards of facet coverage (overlap) on lateral cervical radiographs during voluntary flexion. OBJECTIVE: To produce normative standards for minimum facet coverage in children. SUMMARY OF BACKGROUND DATA: Previous studies on normative standards of facet coverage have been performed only in adults. METHODS: Thirty-six children with minor trauma had lateral flexion-extension radiographs. A standard filming sequence was used in all. Facet joint overlap at each level was divided by the anteroposterior diameter of the upper adjacent cervical body at each level. RESULTS: On linear regression analysis, these ratios did not vary significantly with age at C2-C3 through C6-C7. Means and standard deviations were determined for C2-C7. CONCLUSIONS: These ratios may prove useful in evaluation of children with possible ligamentous injury.

Nuchal cord changes in children with os odontoideum: evidence for associated trauma.

We describe nuchal cord changes in four children with os odontoideum who had cervical spine magnetic resonance imaging (MRI) before surgery. In these four children, nuchal cord changes consistent with previous trauma were seen. The presence of the nuchal cord changes supports the concept of trauma as an etiologic factor in these four cases. This study supports trauma as an associated factor in patients with os odontoideum.

Head-wag autotomography of the upper cervical spine in infantile torticollis.

BACKGROUND: Infants with torticollis require evaluation of the entire cervical spine for vertebral anomalies as part of the work-up, but open-mouth views to assess occiput to C2 are difficult to obtain. OBJECTIVE: To evaluate a "head wag" autotomographic technique for the frontal projection of this region. MATERIALS AND METHODS: Twenty infants under one year of age were evaluated using this technique. RESULTS: Sixteen of 20 could be adequately evaluated using this simple, low-radiation-dose procedure. CONCLUSION: For infants with torticollis in whom vertebral anomalies need to be excluded, the "head wag" technique is useful.