A Dollars and "Sense" Exploration of Vape Shop Spending and E-cigarette Use

INTRODUCTION

Across the US, vape shops have emerged to provide e-cigarette users access to products not usually available at gas stations or retail stores. As vape shop sales have steadily increased, so have questions about the impact of marketing and price on e-cigarette use behaviors. In this exploratory analysis, we aim to characterize spending on e-cigarettes and evaluate the association with customer perceptions and use behaviors.

METHODS

In a cross-sectional survey of vape shop customers (n=78), perceptions and use of e-cigarettes and tobacco products were assessed. Descriptive statistics and multivariate logistic regression were used to evaluate the association between spending and socioeconomic factors, demographics, and use behaviors.

RESULTS

Overall, spending amounts ranged from less than $10/month to more than $250/month, with a median around $50-75/month. Males spent more than females (p=0.003), but spending did not significantly differ by age (p=0.13). Customers who spent more than $50/month used lower levels of nicotine (mg/ml) (p=0.003) but a greater quantity of e-liquid (ml/month) (p<0.0001) compared to customers who spent under that amount. Mod use and intention to use e-cigarettes as a cessation device were significantly associated with vape shop spending in the regression model (OR= 17.5; 95% CI= (4.3, 70.2) and OR=0.22; 95% CI= (0.06, 0.75), respectively).

CONCLUSIONS

Spending appears to be significantly associated with e-cigarette use behaviors. Making "sense" of the potential relationships between the dollars spent at vape shops and consumer use behaviors is important as regulations for e-cigarette sales are proposed.

Transcranial Doppler-Based Surrogates for Cerebral Blood Flow: A Statistical Study

It is commonly assumed that perfusion in a given cerebral territory can be inferred from Blood Flow Velocity (BFV) measurements in the corresponding stem artery. In order to test this hypothesis, we construct a cerebral blood flow (CBF) estimator based on transcranial Doppler (TCD) blood flow velocity and ten other easily available patient characteristics and clinical parameters. A total of 261 measurements were collected from 88 older patients. The estimator is based on local regression (Random Forest). Its performance is analyzed against baseline CBF from 3-D pseudocontinuous arterial spin labeling (pCASL) magnetic resonance imaging (MRI). Patient specific CBF predictions are of poor quality (r = 0.41 and p-value = 4.5 × 10⁻¹²); the hypothesis is thus not clearly supported by evidence.

2016 Comprehensive Update of the Banff Working Group on Liver Allograft Pathology: Introduction of Antibody-Mediated Rejection

The Banff Working Group on Liver Allograft Pathology reviewed and discussed literature evidence regarding antibody-mediated liver allograft rejection at the 11th (Paris, France, June 5-10, 2011), 12th (Comandatuba, Brazil, August 19-23, 2013), and 13th (Vancouver, British Columbia, Canada, October 5-10, 2015) meetings of the Banff Conference on Allograft Pathology. Discussion continued online. The primary goal was to introduce guidelines and consensus criteria for the diagnosis of liver allograft antibody-mediated rejection and provide a comprehensive update of all Banff Schema recommendations. Included are new recommendations for complement component 4d tissue staining and interpretation, staging liver allograft fibrosis, and findings related to immunosuppression minimization. In an effort to create a single reference document, previous unchanged criteria are also included.

Effects of Kinesio taping in patients with quadriceps inhibition: A randomized, single-blinded study

OBJECTIVE

To determine effects of Kinesio taping (KT) on quadriceps activation and maximal voluntary isometric contraction (MVIC) in patients with quadriceps inhibition.

DESIGN

Randomized, single-blinded.

SETTING

Laboratory.

PATIENTS

Sixteen participants (9 males, 7 females) with quadriceps inhibition, as determined by 90% or lower in central activation ratio (CAR), participated.

MAIN OUTCOME MEASURES

Hoffmann reflex (H-reflex) of the vastus medialis and quadriceps CAR and MVIC were measured before taping, and participants were randomly allocated to either KT (KT application with tension) or sham (non-elastic tape application without tension) group. H-reflexes were assessed immediately and 20 min after tape was applied over the rectus femoris. All outcomes were measured again after tape was removed when participants returned the laboratory 24-48 h after taping.

RESULTS

Two-way repeated ANOVA found no group-by-time interaction for: H-reflex (F_3,42 = 1.94, P = 0.14), CAR (F_1,14 = 0.03, P = 0.86), or MVIC (F_1,14 = 0.007, P = 0.93). None of the outcome measures differed between groups or over time (P > 0.05).

CONCLUSIONS

KT applied to the rectus femoris did not change H-reflex of the vastus medialis and quadriceps CAR and MVIC in patients with quadriceps inhibition.

Validity of Torque-Data Collection at Multiple Sites: A Framework for Collaboration on Clinical-Outcomes Research in Sports Medicine

CONTEXT

Collecting torque data using a multimode dynamometer is common in sports-medicine research. The error in torque measurements across multiple sites and dynamometers has not been established.

OBJECTIVE

To assess the validity of 2 calibration protocols across 3 dynamometers and the error associated with torque measurement for each system.

DESIGN

Observational study.

SETTING

3 university laboratories at separate institutions.

EQUIPMENT

2 Biodex System 3 dynamometers and 1 Biodex System 4 dynamometer.

INTERVENTIONS

System calibration was completed using the manufacturer-recommended single-weight method and an experimental calibration method using a series of progressive weights. Both calibration methods were compared with a manually calculated theoretical torque across a range of applied weights.

MAIN OUTCOME MEASURES

Relative error, absolute error, and percent error were calculated at each weight. Each outcome variable was compared between systems using 95% confidence intervals across low (0-65 Nm), moderate (66-110 Nm), and high (111-165 Nm) torque categorizations.

RESULTS

Calibration coefficients were established for each system using both calibration protocols. However, within each system the calibration coefficients generated using the single-weight (System 4 = 2.42 [0.90], System 3a = 1.37 [1.11], System 3b = -0.96 [1.45]) and experimental calibration protocols (System 4 = 3.95 [1.08], System 3a = -0.79 [1.23], System 3b = 2.31 [1.66]) were similar and displayed acceptable mean relative error compared with calculated theoretical torque values. Overall, percent error was greatest for all 3 systems in low-torque conditions (System 4 = 11.66% [6.39], System 3a = 6.82% [11.98], System 3b = 4.35% [9.49]). The System 4 significantly overestimated torque across all 3 weight increments, and the System 3b overestimated torque over the moderate-torque increment.

CONCLUSIONS

Conversion of raw voltage to torque values using the single-calibration-weight method is valid and comparable to a more complex multiweight calibration process; however, it is clear that calibration must be done for each individual system to ensure accurate data collection.

Estimation of mortality risk for vascular operations by trainees vs attending surgeons

OBJECTIVE

The development of the ability to estimate patient mortality preoperatively in surgical trainees has not been well studied.

DESIGN

Prospective comparative study in which the expected perioperative mortality risk and the maximum tolerable mortality at which operation would still be offered were estimated by the operating surgeons immediately before planned vascular procedures.

SETTING

University vascular surgery teaching service.

PARTICIPANTS

Predicted and maximum allowable mortality risks were compared between trainees and attending surgeons, with the mortality calculated using the Veterans Administration Surgical Quality Improvement Program (VASQIP) as a reference.

RESULTS

Surveys were performed before 379 procedures over a 10-month period. The median expected mortality risk predicted by trainees (2%; interquartile range [IQR]: 1%-5%) was higher than the risk predicted by attending surgeons (1%; IQR: 0.8%-3%) (p < 0.01). The median expected mortality risk calculated by VASQIP (0.8%; IQR: 0.4%-1.7%) was less than that estimated by trainees by a median of 0.3% (IQR: 0.2%-3.2%) or and that by attending surgeons by 0.3% (IQR: 0.2-1.3%) (p < 0.01). The median maximum tolerable mortality risk predicted by trainees (10%; IQR: 5%-27.5%) was equal to the risk predicted by attending surgeons (10%; IQR: 5%-17.5%). The perioperative mortality calculated by VASQIP exceeded the maximum tolerable mortality offered by trainees or attending surgeons in 1% of cases each. Discrepancies between expected mortality and maximum tolerable mortality for trainees and attending surgeons were greater for younger (postgraduate year 1 or 2) trainees (0.8%; IQR: 0-3.0%) than for more senior (postgraduate year 4 or 5) trainees (0.4%; IQR: 0.1%-2.0%).

CONCLUSION

Surgeons in training overestimated the perioperative mortality risk of operations and were willing to tolerate a greater mortality risk compared with attending surgeons. Both trainee and attending surgeons tended to overestimate the perioperative mortality risk compared with that calculated by VASQIP.

Tibial tunnel placement accuracy during anterior cruciate ligament reconstruction: independent femoral versus transtibial femoral tunnel drilling techniques

PURPOSE

This study aimed to compare the accuracy of tibial tunnel placement using independent femoral (IF) versus transtibial (TT) techniques.

METHODS

Ten matched pairs of cadaveric knees were randomized so that one knee in the pair underwent arthroscopic TT drilling of the femoral tunnel and the other underwent IF drilling through an accessory medial portal. For both techniques, an attempt was made to place the femoral and tibial tunnels as close to the center of the respective anterior cruciate ligament (ACL) footprints as possible. Preoperative and postoperative computed tomography using a technique optimized for ligament evaluation allowed comparison of the anatomic ACL tibial footprint to the tibial tunnel aperture. The percentage of tunnel aperture contained within the native footprint, as well as the distance from the center of the tunnel aperture to the center of the footprint, was measured. Additionally, graft obliquity relative to the tibial plateau was evaluated in the sagittal plane.

RESULTS

The percentage of tibial tunnel aperture contained within the native footprint averaged 71.6% ± 17.2% versus 52.1% ± 23.4% (P = .04) in the IF and TT groups, respectively. The distance from the center of the footprint to the center of the tibial tunnel aperture was 3.50 ± 1.6 mm and 4.40 ± 1.7 mm (P = .27) in the IF and TT groups, respectively. TT drilling placed 6 of 10 tunnels posterior to the center of the footprint versus 3 of 10 tunnels in IF drilling. The graft obliquity angles were 54.8° in TT specimens and 47.5° in IF specimens (P = .09).

CONCLUSIONS

This study adds to the literature suggesting that TT drilling with an 8-mm reamer has deleterious effects on tibial tunnel aperture and position. IF drilling, which does not involve repeated reaming of the tibial tunnel, is associated with the placement of a higher percentage of the tunnel aperture within the native tibial footprint. There was not a significant difference between the IF and TT techniques in their ability to place the center of the tibial aperture near the center of the footprint or in graft obliquity.

CLINICAL RELEVANCE

ACL reconstruction has continued to evolve in an attempt to restore the functional anatomy and biomechanical behavior of the knee. Tibial tunnel characteristics-such as location, aperture topography, and tunnel obliquity-are important factors to consider in ACL reconstruction. This study compares tibial tunnels after IF and TT techniques.

First case of Chlorella wound infection in a human in Australia

A 30-year-old man developed an infected knee wound 2 days after jumping his bicycle into a freshwater dam. He required repeated debridement and tissue grew bright green colonies typical of the alga Chlorella plus Aeromonas hydrophila. This, and one previously reported case, responded to surgical debridement and careful wound management.

Risk factors for colonization with extended-spectrum beta-lactamase-producing enterobacteriaceae on admission to rehabilitation centres

Patients newly admitted to rehabilitation centres are at high risk of colonization with multidrug-resistant bacteria because many of them have experienced prolonged stays in other healthcare settings and have had high exposure to antibiotics. We conducted a prospective study to determine the prevalence of and risk factors for colonization with extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE) in this population. Subjects were screened by rectal swab for ESBL-PE within 2 days of admission. Swabs were plated on chromagar ESBL plates and the presence of ESBL was verified by a central laboratory. A multilevel mixed effects model was used to identify risk factors for ESBL-PE colonization. Of 2873 patients screened, 748 (26.0%) were positive for ESBL-PE. The variables identified as independently associated with ESBL-PE colonization were: recent stay in an acute-care hospital for over 2 weeks (OR=1.34; 95% CI, 1.12, 1.6), history of colonization with ESBL-PE (OR=2.97; 95% CI, 1.99, 4.43), unconsciousness on admission (OR=2.59; 95% CI, 1.55, 4.34), surgery or invasive procedure in the past year (OR=1.49; 95% CI, 1.2, 1.86) and antibiotic treatment in the past month (OR=1.80; 95% CI, 1.45, 2.22). The predictive accuracy of the model was low (area under the ROC curve 0.656). These results indicate that ESBL-PE colonization is common upon admission to rehabilitation centres. Some risk factors for ESBL-PE colonization are similar to those described previously; however, newly identified factors may be specific to rehabilitation populations. The high prevalence and low ability to stratify by risk factors may guide infection control and empirical treatment strategies in rehabilitation settings.

Clostridium difficile infection diagnosis in a paediatric population: comparison of methodologies

The increasing incidence of Clostridium difficile infection (CDI) in paediatric hospitalised populations, combined with the emergence of hypervirulent strains, community-acquired CDI and the need for prompt treatment and infection control, makes the rapid, accurate diagnosis of CDI crucial. We validated commonly used C. difficile diagnostic tests in a paediatric hospital population. From October 2011 to January 2012, 150 consecutive stools were collected from 75 patients at a tertiary paediatric hospital in Perth, Western Australia. Stools were tested using: C. Diff Quik Chek Complete, Illumigene C. difficile, GeneOhm Cdiff, cycloserine cefoxitin fructose agar (CCFA) culture, and cell culture cytotoxin neutralisation assay (CCNA). The reference standard was growth on CCFA or Cdiff Chromagar and PCR on isolates to detect tcdA, tcdB, cdtA, and cdtB. Isolates were PCR ribotyped. The prevalence of CDI was high (43 % of patients). Quik Chek Complete glutamate dehydrogenase (GDH) demonstrated a low negative predictive value (NPV) (93 %). Both CCNA and Quik Chek Complete toxin A/B had poor sensitivity (33 % and 29 % respectively). Molecular methods both had 89 % sensitivity. Algorithms using GDH + Illumigene or GeneOhm reduced the sensitivity to 85 % and 83 % respectively. Ribotype UK014/20 predominated. GDH NPV and GeneOhm and Illumigene sensitivities were reduced compared with adult studies. Quik Chek Complete and CCNA cannot reliably detect toxigenic CDI. A GDH first algorithm showed reduced sensitivity. In a high prevalence paediatric population, molecular methods alone are recommended over the use of GDH algorithm or culture and CCNA, as they demonstrate the best test performance characteristics.