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iPLEDGE and exposure management systems: How lack of language options may impede health equity
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Older age is a predictor for hardware failure in open lower extremity fractures requiring free flap coverage
No full textBackground: The primary objective of this study was to investigate incidence and factors associated with hardware failure in a cohort of patients with open tibial and ankle fractures who underwent free flap coverage in conjunction with open reduction and internal fixation (ORIF) and hardware placement. Secondary objectives were to determine incidence of fracture union and limb salvage. Finally, we sought to identify flap-related factors that might impact rates of infection, flap failure, and nonunion. Methods: A consecutive single-surgeon series was studied. Baseline patient characteristics, flap-related factors, incidence of hardware failure, amputation, and non-union were extracted and analyzed. Results: A total of 37 consecutive patients with a mean age of 38.9 ± 16.4 years were included, with a mean postoperative follow-up of 703.4 ± 459.6 days. There were 9 patients (24.3 %) with hardware failure and deep tissue infection. Time from injury to flap and time from last ORIF to flap were not significantly different between patients with hardware failure and those without. Flap type (muscle versus fasciocutaneous), smoking status, diabetes and body mass index were not associated with hardware failure. Multivariate regression analysis controlling for potential confounders showed that older age in patients was the only significant factor predicting hardware failure. Bone union was achieved in 29 (78.4 %) patients. Mean time from surgery to radiological signs of union was 329.3 ± 425.3 days. Conclusion: In patients requiring free flap reconstruction and ORIF for open tibial and ankle fractures, age was the only significant non-modifiable risk factor for hardware failure
Illustrated ultrasound evaluation of the stomach fasting/nonfasting status
No full textPerioperative pulmonary aspiration is a feared complication of anesthesia especially in pregnancy, associated with potentially fatal lung injuries such as pneumonitis, pneumonia, and acute respiratory distress syndrome. Although pulmonary aspiration is rare, affecting 1 in every 2000-3000 patients undergoing general anesthesia, the incidence accounts for over 50% of airway-related deaths in anesthesia. The presence of gastric contents prior to induction of anesthesia greatly amplifies the risk of perioperative pulmonary aspiration. This chapter focuses on the use of ultrasound to assess gastric volume and contents for perioperative aspiration management and improvement in anesthesia safety. Although fasting guidelines implemented by the American Society of Anesthesiologists allow time for gastric emptying, patients with obscure NPO status or comorbidities such as pregnancy, placing them at risk of a higher gastric volume may benefit from additional testing and standards. At present, gastric ultrasound is a simple, noninvasive, diagnostic tool shown to be effective in assessing the qualitative nature of gastric content and quantitative calculation of gastric volume. Information from gastric ultrasound aids anesthesia providers in optimizing timing, induction, and airway management techniques. Nevertheless, with limitations involving sonographer training, accurate analysis of gastric contents, and standardization of protocols, the widespread adoption of the practice is lagging
Acetate derived from metabolism of ethanol affects gene expression in bone and contributes to delays in chondrogenic differentiation
No full textAlcohol intake is a risk factor for development of osteopenia. Ethanol perturbs gene expression in osteoblasts and osteoclasts and disrupts growth plate morphology. Hepatic metabolism of ethanol to acetate elevates concentrations of acetate in the circulation. We investigated whether acetate could in part mediate the toxicity of ethanol in bone and on chondrocyte differentiation. When ethanol and acetate were compared by gavage for four consecutive days, none of eleven genes involved in bone homeostasis were significantly affected by acetate, but acetate responses significantly correlated with ethanol responses. Intraperitoneal injection with acetate to transiently elevate serum acetate for four consecutive days significantly increased expression of two markers of osteoclast differentiation, calcitonin receptor (Calcr) and Ocstamp. Early chondrogenic differentiation of ATDC5 cells for 7 days in vitro characterized by aggrecan (Acan) and collagen 2a1 (Col2a1) mRNA expression and proteoglycan production was inhibited by both 50 mM ethanol and 5 mM acetate. Ethanol effects were not blocked by the alcohol dehydrogenase inhibitor 4-methylpyrazole. 50 mM ethanol retarded both ATDC5 cell growth and culture medium acidification. Inhibition of chondrogenic differentiation by 5 mM acetate was associated with elevated phosphorylation of ERK1 and ERK2 and decreased expression of transcription factors Sox9 and Runx2. In acetate-exposed cells, blocking of ERK1 and ERK2 phosphorylation with Trametinib prevented further reduction of Acan and Col2a1 mRNA expression. We conclude that ethanol-derived acetate mediates at least part of the induction of Calcr and Ocstamp expression, and that acetate mimics effects of ethanol on early chondrogenic differentiation
Chronic inflammatory pain and chronic THC vapor inhalation alter midbrain neuronal activity
Get PDFIn an effort to reduce reliance on opioids for the treatment of pain in the clinic, ongoing work is testing the utility of cannabinoid drugs as a potential alternative for treatment of chronic pain. We tested chronic delta-9 tetrahydrocannabinol (THC) vapor inhalation effects on intrinsic and synaptic properties of ventrolateral periaqueductal gray (vlPAG) neurons in male and female rats treated with complete Freund\u27s adjuvant (CFA). We report that chronic THC vapor inhalation modulates intrinsic and synaptic properties of vlPAG neurons, including reductions in action potential firing rate and spontaneous inhibitory synaptic transmission in males, and that these effects occur specifically in neurons that respond to current input with a delayed firing phenotype. Treatment with CFA led to increased firing rate and increased spontaneous inhibitory postsynaptic current (sIPSC) amplitude in vlPAG neurons of female rats, and chronic THC vapor rescued sIPSC amplitudes to control levels-these effects in females were specific to vlPAG neurons categorized as having an onset firing phenotype. Ongoing work is exploring sex-specific mechanisms and cell types involved in THC vapor inhalation effects on vlPAG neurons in rats treated with CFA, and determining the role of these changes in THC vapor inhalation effects on pain-related behavior. Many in the United States with pain self-medicate with delta-9 tetrahydrocannabinol (THC) and cannabis, and many humans use e-cigarette-type devices filled with cannabis extracts to self-administer THC. Until recently, most rodent studies have used injection procedures and male rats. Chronic THC vapor reduced synaptic inhibition and neural firing in ventrolateral periaqueductal gray (vlPAG) neurons in males and rescued chronic inflammatory pain-induced increase in synaptic inhibition in females
ELV-N34, RvD6-Isomer, or NPD1 Halt Replication of SARS-CoV-2 Omicron BA.5 Virus in Human Lung and Nasal Cells
Get PDFCurrent vaccines rely on the sequence of Spike (S) protein to induce immunity against the severe acute respiratory coronavirus-2 (SARS-CoV-2) virus. Because of the high mutation rate of the viral S protein, new mutant strains are developed to generate new infectivity profiles. Bioactive lipid mediators (LMs) derived from docosahexaenoic acid (DHA) are synthesized on demand to sustain homeostasis. The purpose of this study was to determine the action of selected LMs in the viral replication of SARS-CoV-2 Omicron BA.5 variant in human lung and nasal epithelial cells. Cells from healthy donors were infected with Omicron BA.5 for one hour and treated with 500 nM Elovanoid (ELV)-N32, ELV-N34, Resolvin D6 isomer (RvD6i), Neuroprotection D1 (NPD1), or vehicle before and after infection. Impedance was recorded to determine cell death by infectivity. Cells were then immunostained for nucleocapsid (N) protein, microtubule-associated protein 1B-light chain 3 (LC3B), and autophagic proteins. N and S RNA were measured to assess the synthesis of viral components. The addition of ELV-N34 or RvD6i decreased the synthesis of N RNA by 76.7% and 96.9%, respectively, in lung primary culture, while NPD1 exerted the same effect in nasal epithelial cells (61.7% reduction). In lung cells, transcription of autophagy-related gene-3 (ATG3) and Sequestosome 1 (SQSTM1/p62), components of the autophagy initiation process, decreased compared to the non-treated infected cells. The results suggest that specific LMs prevent viral autophagy machinery hijacking, leading to a decrease in BA.5 replication. This novel effect of the bioactive LMs as antivirals, regardless of the protein sequence, would potentially complement vaccination and other prevention and treatment therapeutics
Kurt Varner Interview
Get PDFThis interview of Dr. Kurt Varner was conducted by Chandler Smith on June 13, 2025. Interview transcribed by John Gore.https://digitalscholar.lsuhsc.edu/oral_hist/1008/thumbnail.jp
Effect of ceramic type, cement shade, and ceramic thickness on the optical properties of the definitive restoration and the ability to mask a metal substructure
No full textSTATEMENT OF PROBLEM: The influence of ceramic type, cement shade, and ceramic thickness on the final color of the restoration and its masking ability is unclear. PURPOSE: The purpose of this in vitro study was to investigate the effect of the ceramic type and translucency parameters, ceramic thickness, and cement shade on the color of the definitive restoration and its masking ability. MATERIAL AND METHODS: A total of 120 ceramic specimens were fabricated in different thicknesses and divided into 10 groups: high translucency zirconia (HTZ 0.8, 1.2, 1.6 and 2 mm) (ZX2 98; Dental Direct), porcelain-fused-to-zirconia (PFZ1.5 and 2 mm) (DD Bio ZW iso color High Strength; Dental Direkt), monolithic low translucency lithium disilicate (LT 1 and 1.5 mm) (e.max; Ivoclar AG), bilayered glass-ceramic with a high opaque lithium disilicate (HO 1.5 and 2 mm) (e.max; Ivoclar AG). The color and translucency of the specimens were measured based on the L*a*b values and remeasured after applying resin cement evaluation pastes (Panavia V5 Try in paste; Kuraray Dental) in 3 colors: A2, opaque (O), or white (W) over 2 background materials (nickel chromium alloy or composite resin shade A2). The VITA Classic shade guide was used as the reference L*a*b value to evaluate the color matching capability of different ceramic-cement combinations. Color change (ΔE) was measured, and the perceptibility threshold (PT) was set at 2.6 and the acceptability threshold (AT) at 5.5. RESULTS: The mean ΔE of the specimens ranged from 0.4 to 4.5. The type of ceramic significantly affected the color and translucency parameter (P \u3c .001). In all groups, translucency decreased significantly with the increasing thickness of the ceramic (P \u3c .001). According to the perceptibility threshold, the color of the nickel chromium background could be concealed by all 2 shades of cement (A2, opaque, and white). Nevertheless, the LT 1-mm, LT 1.5-mm, HTZ 0.8-mm, and HTZ 1.2-mm groups exhibited noticeable color changes when opaque cement was applied. Specimens with lower translucency parameters had better color matching with the A2 color. The HTZ 0.8-mm A2, LT 1-mm A2, and HTZ 0.8-mm W groups showed the least color match, with mean ΔE values of 12.4, 11.9, and 11.3, respectively. However, the PFZ 2-mm O and PFZ 2-mm W groups exhibited the best color match, with mean ΔE values of 1 and 1.4. CONCLUSIONS: The thickness of the ceramic had a significant effect on its translucency. Moreover, the translucency of the ceramic influenced its masking ability and had a direct correlation with the color change in the presence of cement. Ceramic materials with an opaque framework had lower translucency but better color matching with the reference shade
A Virtual Research Nurse Framework to Support Clinical Trials in Community Oncology Practices.
No full textMost cancer patients are diagnosed and treated in community oncology practices. However, their participation in clinical trials is low. A common barrier to clinical trial enrollment in the community is the lack of research infrastructure and experienced research personnel. Unique strategies to address the needs of community sites, especially those not affiliated with large cancer centers, are needed. We describe how the Gulf South Clinical Trials Network, a minority/underserved National Cancer Institute Community Oncology Research Program community site, has developed Virtual Research Nurse program to provide virtual research support to urban and rural community oncology clinics to increase participation in cancer clinical trials