The Structural Analysis: Incorporating Structurally Competent Clinical Reasoning into Case-Based Presentations.

Structural and social determinants of health account for the health disparities we see along social hierarchies, and their impact has been made more evident by the recent COVID-19 pandemic. There have been increasing calls to incorporate structural competency into medical education. The structural and social context, however, has yet to be fully integrated into everyday clinical practice and little has been published on how to concretely imbed structural competency into clinical reasoning. The authors provide a framework for structural analysis, which incorporates four key steps: (1) developing a prioritized clinical problem list, (2) identifying social and structural root causes for clinical problems, (3) constructing and documenting a prioritized structural problem list, and (4) brainstorming solutions to address structural barriers and social needs. They show how structural analysis can be used to operationalize structural reasoning into everyday inpatient and outpatient clinical assessments.

Factors Associated with Long-Term Retention in Buprenorphine-Based Addiction Treatment Programs: a Systematic Review.

BACKGROUND: The average length of buprenorphine treatment for opioid use disorder is less than 6 months. OBJECTIVE: We conducted a systematic review to determine what factors were associated with longer retention in buprenorphine treatment. DESIGN: We searched Medline, Embase, and Cochrane Database of Systematic Reviews in February 2018. Articles were restricted to randomized controlled trials on human subjects, written in English, which contained ≥ 24 weeks of objective data on retention in buprenorphine treatment. MAIN MEASURES: We assessed whether dose of buprenorphine, treatment setting, or co-administration of behavioral therapy was associated with retention rates. KEY RESULTS: Over 14,000 articles were identified. Thirteen articles (describing 9 studies) met inclusion criteria. Measures of retention varied widely. Three studies compared doses of buprenorphine between 1 and 8 mg and showed significantly higher rates of retention with higher doses (p values < 0.01). All other studies utilized buprenorphine doses between 8 and 24 mg daily, without comparison. No study found a significant difference in retention between buprenorphine alone and buprenorphine plus behavioral therapy (p values > 0.05). Initiating buprenorphine while hospitalized or within criminal justice settings prior to outpatient treatment programs was significantly associated with retention in buprenorphine treatment (p values < 0.01 respectively). CONCLUSIONS: Setting of treatment initiation and a higher buprenorphine dose are associated with improved long-term treatment retention. More objective data on buprenorphine treatment programs are needed, including a standardized approach to defining retention in buprenorphine treatment programs. REGISTRATION: This review was registered with PROSPERO (#CRD42019120336) in March 2019.

The Effect of Microcosm Biofilm Decontamination on Surface Topography, Chemistry, and Biocompatibility Dynamics of Implant Titanium Surfaces.

Since the inception of dental implants, a steadily increasing prevalence of peri-implantitis has been documented. Irrespective of the treatment protocol applied for the management of peri-implantitis, this biofilm-associated pathology, continues to be a clinical challenge yielding unpredictable and variable levels of resolution, and in some cases resulting in implant loss. This paper investigated the effect of microcosm biofilm in vitro decontamination on surface topography, wettability, chemistry, and biocompatibility, following decontamination protocols applied to previously infected implant titanium (Ti) surfaces, both micro-rough -Sandblasted, Large-grit, Acid-etched (SLA)-and smooth surfaces -Machined (M). Microcosm biofilms were grown on SLA and M Ti discs. These were treated with TiBrushes (TiB), combination of TiB and photodynamic therapy (PDT), combination of TiB and 0.2%CHX/1%NaClO, plus or minus Ultraviolet-C (UV-C) radiation. Surface topography was evaluated by Scanning Electron Microscopy (SEM) and Laser Surface Profilometry. Surface function was analysed through wettability analysis. Surface chemistry evaluation of the discs was performed under SEM/Energy-dispersive X-ray spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS). Biocompatibility was tested with the cytocompatibility assay using human osteoblast-like osteosarcoma cell line (MG-63) cells. Elemental analysis of the discs disclosed chemical surface alterations resulting from the different treatment modalities. Titanium, carbon, oxygen, sodium, aluminium, silver, were identified by EDX as the main components of all the discs. Based on the data drawn from this study, we have shown that following the decontamination of Ti surfaces the biomaterial surface chemistry and topography was altered. The type of treatment and Ti surface had a significant effect on cytocompatibility (p = 0.0001). Although, no treatment modality hindered the titanium surface biocompatibility, parameters such as the use of chemical agents and micro-rough surfaces had a higher cytotoxic effect in MG-63 cells. The use of smooth surfaces, and photofunctionalisation of the TiO2 layer had a beneficial effect on cytocompatibility following decontamination.

Reactive Oxygen Stimulation of Interleukin-6 Release in the Human Trophoblast Cell Line HTR-8/SVneo by the Trichlorethylene Metabolite S-(1,2-Dichloro)-l-Cysteine.

Trichloroethylene (TCE) is a common environmental pollutant associated with adverse reproductive outcomes in humans. TCE intoxication occurs primarily through its biotransformation to bioactive metabolites, including S-(1,2-dichlorovinyl)-l-cysteine (DCVC). TCE induces oxidative stress and inflammation in the liver and kidney. Although the placenta is capable of xenobiotic metabolism and oxidative stress and inflammation in placenta have been associated with adverse pregnancy outcomes, TCE toxicity in the placenta remains poorly understood. We determined the effects of DCVC by using the human extravillous trophoblast cell line HTR-8/SVneo. Exposure to 10 and 20 µM DCVC for 10 h increased reactive oxygen species (ROS) as measured by carboxydichlorofluorescein fluorescence. Moreover, 10 and 20 µM DCVC increased mRNA expression and release of interleukin-6 (IL-6) after 24-h exposure, and these responses were inhibited by the cysteine conjugate beta-lyase inhibitor aminooxyacetic acid and by treatments with antioxidants (alpha-tocopherol and deferoxamine), suggesting that DCVC-stimulated IL-6 release in HTR-8/SVneo cells is dependent on beta-lyase metabolic activation and increased generation of ROS. HTR-8/SVneo cells exhibited decreased mitochondrial membrane potential at 5, 10, and 20 µM DCVC at 5, 10, and 24 h, showing that DCVC induces mitochondrial dysfunction in HTR-8/Svneo cells. The present study demonstrates that DCVC stimulated ROS generation in the human placental cell line HTR-8/SVneo and provides new evidence of mechanistic linkage between DCVC-stimulated ROS and increase in proinflammatory cytokine IL-6. Because abnormal activation of cytokines can disrupt trophoblast functions necessary for placental development and successful pregnancy, follow-up investigations relating these findings to physiologic outcomes are warranted.

Prospective evaluation of prehospital trauma ultrasound during aeromedical transport.

BACKGROUND: Ultrasound is widely considered the initial diagnostic imaging modality for trauma. Preliminary studies have explored the use of trauma ultrasound in the prehospital setting, but the accuracy and potential utility is not well understood. OBJECTIVE: We sought to determine the accuracy of trauma ultrasound performed by helicopter emergency medical service (HEMS) providers. METHODS: Trauma ultrasound was performed in flight on adult patients during a 7-month period. Accuracy of the abdominal, cardiac, and lung components was determined by comparison to the presence of injury, primarily determined by computed tomography, and to required interventions. RESULTS: HEMS providers performed ultrasound on 293 patients during a 7-month period, completing 211 full extended Focused Assessment with Sonography for Trauma (EFAST) studies. HEMS providers interpreted 11% of studies as indeterminate. Sensitivity and specificity for hemoperitoneum was 46% (95% confidence interval [CI] 27.1%-94.1%) and 94.1% (95% CI 89.2%-97%), and for laparotomy 64.7% (95% CI 38.6%-84.7%) and 94% (95% CI 89.2%-96.8%), respectively. Sensitivity and specificity for pneumothorax were 18.7% (95% CI 8.9%-33.9%) and 99.5% (95% CI 98.2%-99.9%), and for thoracostomy were 50% (95% CI 22.3%-58.7%) and 99.8% (98.6%-100%), respectively. The positive likelihood ratio for laparotomy was 10.7 (95% CI 5.5-21) and for thoracostomy 235 (95% CI 31-1758), and the negative likelihood ratios were 0.4 (95% CI 0.2-0.7) and 0.5 (95% CI 0.3-0.8), respectively. Of 240 cardiac studies, there was one false-positive and three false-negative interpretations (none requiring intervention). CONCLUSIONS: HEMS providers performed EFAST with moderate accuracy. Specificity was high and positive interpretations raised the probability of injury requiring intervention. Negative interpretations were predictive, but sensitivity was not sufficient for ruling out injury.

Botox in below knee amputation for the management of post-operative contracture: a systematic review.

During the 1970s, scientists first used botulinum toxin to treat strabismus. While testing on monkeys, they noticed that the toxin could also reduce wrinkles in the glabella area. This led to its widespread use in both medical and cosmetic fields. The objective of the study was to evaluate the potential use of Botox in managing post-operative contracture after below-knee amputation. We conducted a systematic review In Pubmed, Cochrane Library, Embase, and Google Scholar using the MESH terms Botox, botulinum toxin, post-operative contracture, amputation, and below knee amputation. Our goal was to evaluate the potential use of Botox to manage post-operative contracture in patients who have undergone below-knee amputation. Our findings show evidence in the literature that Botox can effectively manage stump hyperhidrosis, phantom pain, and jumping stump, but no clinical trial has been found that discusses the use of Botox for post-operative contracture. Botox has been used in different ways to manage spasticity. Further studies and clinical trials are needed to support the use of Botox to manage this complication.

Probing cognitive flexibility in Shank2-deficient mice: Effects of D-cycloserine and NMDAR signaling hub dynamics.

Neurodevelopmental disorders such as autism spectrum disorder (ASD) have a heterogeneous etiology but are largely associated with genetic factors. Robust evidence from recent human genetic studies has linked mutations in the Shank2 gene to idiopathic ASD. Modeling these Shank2 mutations in animal models recapitulates behavioral changes, e.g. impaired social interaction and repetitive behavior of ASD patients. Shank2-deficient mice exhibit NMDA receptor (NMDAR) hypofunction and associated behavioral deficits. Of note, NMDARs are strongly implicated in cognitive flexibility. Their hypofunction, e.g. observed in schizophrenia, or their pharmacological inhibition leads to impaired cognitive flexibility. However, the association between Shank2 mutations and cognitive flexibility is poorly understood. Using Shank2-deficient mice, we explored the role of Shank2 in cognitive flexibility measured by the attentional set shifting task (ASST) and whether ASST performance in Shank2-deficient mice can be modulated by treatment with the partial NMDAR agonist D-cycloserine (DCS). Furthermore, we investigated the effects of Shank2 deficiency, ASST training, and DCS treatment on the expression level of NMDAR signaling hub components in the orbitofrontal cortex (OFC), including NMDAR subunits (GluN2A, GluN2B, GluN2C), phosphoglycerate dehydrogenase and serine racemase. Surprisingly, Shank2 deficiency did not affect ASST performance or alter the expression of the investigated NMDAR signaling hub components. Importantly, however, DCS significantly improved ASST performance, demonstrating that positive NMDAR modulation facilitates cognitive flexibility. Furthermore, DCS increased the expression of GluN2A in the OFC, but not that of other NMDAR signaling hub components. Our findings highlight the potential of DCS as a pharmacological intervention to improve cognitive flexibility impairments downstream of NMDAR modulation and substantiate the key role of NMDAR in cognitive flexibility.

Ammonium perchlorate: serum dosimetry, neurotoxicity, and resilience of the neonatal rat thyroid system.

The environmental contaminant perchlorate impairs the synthesis of thyroid hormones by reducing iodine uptake into the thyroid gland. Despite this known action, moderate doses of perchlorate do not significantly alter serum thyroid hormone in rat pups born to exposed dams. We examined perchlorate dosimetry and responsivity of the thyroid gland and brain in offspring following maternal exposure to perchlorate. Pregnant rat dams were delivered perchlorate in drinking water (0, 30, 100, 300, 1000 ppm) from gestational day 6 to postnatal day (PN) 21. Perchlorate was present in the placenta, milk, and serum, the latter declining in pups over the course of lactation. Serum and brain thyroid hormone were reduced in pups at birth but recovered to control levels by PN2. Dramatic upregulation of Nis was observed in the thyroid gland of the exposed pup. Despite the return of serum thyroid hormone to control levels by PN2, expression of several TH-responsive genes was altered in the PN14 pup brain. Contextual fear learning was unimpaired in the adults, supporting previous reports. Declining levels of serum perchlorate and a profound upregulation of Nis gene expression in the thyroid gland are consistent with the rapid return to the euthyroid state in the neonate. However, despite this recovery, thyroid hormone insufficiencies in serum and brain beginning in utero and present at birth appear sufficient to alter TH action in the fetus and subsequent trajectory of brain development. Biomarkers of that altered trajectory remain in the brain of the neonate, demonstrating that perchlorate is not devoid of effects on the developing brain.

Evaluation of a training curriculum for prehospital trauma ultrasound.

BACKGROUND: In the United States, ultrasound has rarely been incorporated into prehospital care, and scant descriptions of the processes used to train prehospital providers are available. OBJECTIVES: Our objective was to evaluate the effectiveness of an extended focused assessment with sonography for trauma (EFAST) training curriculum that incorporated multiple educational modalities. We also aimed to determine if certain demographic factors predicted successful completion. METHODS: All aeromedical prehospital providers (APPs) for a Level I trauma center took a 25-question computer-based test to ascertain baseline knowledge. Questions were categorized by content and format. Training over a 2-month period included a didactic course, a hands-on training session, proctored scanning sessions in the Emergency Department, six Internet-based training modules, pocket flashcards, a review session, and remedial training. At the conclusion of the training curriculum, the same test and an objective structured clinical examination were administered to evaluate knowledge gained. RESULTS: Thirty-three of 34 APPs completed training. The overall pre-test and post-test means and all content and format subsets showed significant improvement (p < 0.0001 for all). No APP passed the pre-test, and 28 of 33 passed the post-test with a mean score of 78%. No demographic variable predicted passing the post-test. Twenty-seven of 33 APPs passed the objective structured clinical examination, and the only predictive variable was passing the post-test (odds ratio 1.21, 95% confidence interval 1.00-1.25, p = 0.045). CONCLUSION: The implementation of a multifaceted EFAST prehospital training program is feasible. Significant improvement in overall and subset testing scores suggests that the test instrument was internally consistent and sufficiently sensitive to capture knowledge gained as a result of the training. Demographic variables were not predictive of test success.

Two Cases of Venous Thromboembolism Shortly After Adenovirus-Based COVID-19 Vaccination.

As the coronavirus disease 2019 (COVID-19) global pandemic continues, multiple vaccines have been developed to decrease infection rate and number of deaths. Vaccine administration is especially important as new COVID-19 variants emerge. While the number of severe thromboembolic events reported after adenovirus-based vaccination has gained attention, there is little information regarding the presentation and management of post-vaccination venous thromboembolism (VTE). Here, we present two cases of VTE after the Janssen vaccine administration. In the first case, a 98-year-old African American female with hypertension developed bilateral lower extremity edema that evolved into unilateral lower extremity edema 20-35 days following the Janssen vaccine administration. She was found to have an extensive unilateral proximal femoral deep vein thrombosis (DVT) 35 days after the vaccination. In the second case, a 64-year-old African American female developed ecchymosis and unilateral edema six days after the Janssen vaccine administration. She was found to have proximal superficial vein thrombosis two days later. In both cases, laboratory data, including platelets and anti-heparin antibodies were within normal limits. Thus, VTE may be an adverse effect of the Janssen vaccine or any adenovirus-based vaccine, but further surveillance and investigation to elucidate this association are necessary. We advise practitioners to have a high index of suspicion for thrombosis after Janssen vaccine administration, regardless of the presence of thrombocytopenia, and avoidance of heparin products until heparin antibody results return.

Bacterial Species Causing Secondary Pneumonia Infection in Pregnant Women with COVID-19.

Sputum samples were taken from pregnant women infected with the COVID-19, where the study was conducted on 112 cases, and the results showed that 87 cases developed secondary bacterial infections at a rate of 78% and 25 cases were negative by 22%. The samples were cultured on solid media and incubated at 37°C. Then the samples were diagnosed by biochemical tests and using the API system. Six species of bcteria have been isolated (S. aureus, K.pneumonia P. auroginosa, H. influenza, S. pneumonia S. pyogens) by 31, 29, 12, 10, 7, and 5 isolates, respectively, where the result showed that the most common types of pneumonia were S. aureus with a percentage of 34%, followed by K. pneumonia with a percentage of 29%. The sensitivity of the isolates to eight types of common antibiotics was tested (Erythromycin, Trimethoprim, Ampicillin, Tetracycline, Augmentin, Nitrofurantoin, Meropenem, and Amikacin), where the isolates showed a high resistance to antibiotics (Erythromycin, Trimethoprim, Ampicillin), a high sensitivity of 100% to the Nitrofurantoin, and an average sensitivity to other antibiotics.

Consensus on Social Determinants of Health Knowledge Topics and Behavior Learning Goals Across Primary Care Residencies: Results of a Delphi Study.

PURPOSE: Social determinants of health (SDH) are a substantial contributor to health outcomes and health inequities across populations. The Accreditation Council for Graduate Medical Education has called for the incorporation of SDH into graduate medical education (GME), yet there is no consensus on what SDH knowledge or skills residents in primary care specialties should have on completion of training. The aim of this study was to develop expert consensus on the most important SDH knowledge topics and behavior learning goals for residents in 4 primary care fields. METHOD: The authors used a modified Delphi technique to develop consensus among experts in internal medicine, pediatrics, family medicine, and obstetrics and gynecology across the United States via a survey administered between February and October 2021. They conducted a literature review on SDH in GME to develop an initial set of topics and learning goals and recruited experts who published about SDH and GME or led an SDH curriculum in GME. Consensus was determined a priori as 80% agreement that a topic or learning goal was very or extremely important. RESULTS: Forty-one experts participated in the first round of the survey and 33 participated in the second round (80% retention). Experts reached consensus on the importance of 22/51 (43%) topics and 18/47 (38%) learning goals. Topics reaching consensus emphasized structural forces, broad domains of SDH, resources for addressing SDH, and advocacy strategies and resources. Learning goals reaching consensus focused on individual- and interpersonal-level behaviors. CONCLUSIONS: To the authors' knowledge, this study represents the first rigorous evaluation of expert consensus on SDH in GME across 4 primary care specialties. The results could inform curriculum development and implementation and program evaluation, residency program goals, and shared GME milestones. Among other things, future studies can assess expert consensus on SDH in GME across nonprimary care specialties.

Gestational Exposure to Perchlorate in the Rat: Thyroid Hormones in Fetal Thyroid Gland, Serum, and Brain.

Iodine is essential for the production of thyroid hormones. Perchlorate is an environmental contaminant that interferes with iodine uptake into the thyroid gland to reduce thyroid hormone synthesis. As thyroid hormones are critical for brain development, exposure to perchlorate during pregnancy is of concern for the developing fetal brain. In this study, we (1) define profiles of thyroid hormone in the maternal and fetal compartments of pregnant rats in response to inhibition of the sodium-iodide symporter (NIS) by perchlorate and (2) expand inquiry previously limited to serum to include fetal thyroid gland and brain. Perchlorate was added to the drinking water (0, 1, 30, 300, and 1000 ppm) of pregnant rat dams from gestational days (GD) 6-20. On GD20, blood, thyroid gland, and brain were collected from the fetus and dam for thyroid hormone and molecular analyses. Thyroid gland and serum thyroid hormones were dose-dependently reduced, with steeper declines evident in the fetus than in the dam. The thyroid gland revealed perturbations of thyroid hormone-action with greater sensitivity in the fetus than the dam. Thyroid hormones and thyroid hormone-responsive gene expression were reduced in the fetal cortex portending effects on brain development. These findings are the first quantitative assessments of perchlorate-induced deficits in the fetal thyroid gland and fetal brain. We provide a conceptual framework to develop a quantitative NIS adverse outcome pathway for serum thyroid hormone deficits and the potential to impact the fetal brain. Such a framework may also serve to facilitate the translation of in vitro bioactivity to the downstream in vivo consequences of NIS inhibition in the developing fetus.

Mechanistic Computational Model for Extrapolating In Vitro Thyroid Peroxidase (TPO) Inhibition Data to Predict Serum Thyroid Hormone Levels in Rats.

High-throughput in vitro assays are developed to screen chemicals for their potential to inhibit thyroid hormones (THs) synthesis. Some of these experiments, such as the thyroid peroxidase (TPO) inhibition assay, are based on thyroid microsomal extracts. However, the regulation of thyroid disruption chemicals is based on THs in vivo serum levels. This necessitates the estimation of thyroid disruption chemicals in vivo tissue levels in the thyroid where THs synthesis inhibition by TPO takes place. The in vivo tissue levels of chemicals are controlled by pharmacokinetic determinants such as absorption, distribution, metabolism, and excretion, and can be described quantitatively in physiologically based pharmacokinetic (PBPK) models. An integrative computational model including chemical-specific PBPK and TH kinetics models provides a mechanistic quantitative approach to translate thyroidal high-throughput in vitro assays to in vivo measures of circulating THs serum levels. This computational framework is developed to quantitatively establish the linkage between applied dose, chemical thyroid tissue levels, thyroid TPO inhibition potential, and in vivo TH serum levels. Once this link is established quantitatively, the overall model is used to calibrate the TH kinetics parameters using experimental data for THs levels in thyroid tissue and serum for the 2 drugs, propylthiouracil and methimazole. The calibrated quantitative framework is then evaluated against literature data for the environmental chemical ethylenethiourea. The linkage of PBPK and TH kinetics models illustrates a computational framework that can be extrapolated to humans to screen chemicals based on their exposure levels and potential to disrupt serum THs levels in vivo.

Thyroid Disruptors: Extrathyroidal Sites of Chemical Action and Neurodevelopmental Outcome-An Examination Using Triclosan and Perfluorohexane Sulfonate.

Many xenobiotics are identified as potential thyroid disruptors due to their action to reduce circulating levels of thyroid hormone, most notably thyroxine (T4). Developmental neurotoxicity is a primary concern for thyroid disrupting chemicals yet correlating the impact of chemically induced changes in serum T4 to perturbed brain development remains elusive. A number of thyroid-specific neurodevelopmental assays have been proposed, based largely on the model thyroid hormone synthesis inhibitor propylthiouracil (PTU). This study examined whether thyroid disrupting chemicals acting distinct from synthesis inhibition would result in the same alterations in brain as expected with PTU. The perfluoroalkyl substance perfluorohexane sulfonate (50 mg/kg/day) and the antimicrobial Triclosan (300 mg/kg/day) were administered to pregnant rats from gestational day 6 to postnatal day (PN) 21, and a number of PTU-defined assays for neurotoxicity evaluated. Both chemicals reduced serum T4 but did not increase thyroid stimulating hormone. Both chemicals increased expression of hepatic metabolism genes, while thyroid hormone-responsive genes in the liver, thyroid gland, and brain were largely unchanged. Brain tissue T4 was reduced in newborns, but despite persistent T4 reductions in serum, had recovered in the PN6 pup brain. Neither treatment resulted in a low dose PTU-like phenotype in either brain morphology or neurobehavior, raising questions for the interpretation of serum biomarkers in regulatory toxicology. They further suggest that reliance on serum hormones as prescriptive of specific neurodevelopmental outcomes may be too simplistic and to understand thyroid-mediated neurotoxicity we must expand our thinking beyond that which follows thyroid hormone synthesis inhibition.

Whole Genome Sequencing of SARS-CoV-2 Strains in COVID-19 Patients From Djibouti Shows Novel Mutations and Clades Replacing Over Time.

Since the start of COVID-19 pandemic the Republic of Djibouti, in the horn of Africa, has experienced two epidemic waves of the virus between April and August 2020 and between February and May 2021. By May 2021, COVID-19 had affected 1.18% of the Djiboutian population and caused 152 deaths. Djibouti hosts several foreign military bases which makes it a potential hot-spot for the introduction of different SARS-CoV-2 strains. We genotyped fifty three viruses that have spread during the two epidemic waves. Next, using spike sequencing of twenty-eight strains and whole genome sequencing of thirteen strains, we found that Nexstrain clades 20A and 20B with a typically European D614G substitution in the spike and a frequent P2633L substitution in nsp16 were the dominant viruses during the first epidemic wave, while the clade 20H South African variants spread during the second wave characterized by an increase in the number of severe forms of COVID-19.

Keratinocyte and lymphocyte apoptosis: relation to disease outcome in systemic lupus erythematosus patients with and without cutaneous manifestations.

Our aim was to assess the relationship of keratinocyte and lymphocyte apoptosis and macrophage function to disease outcome in systemic lupus erythematosus patients with and without cutaneous manifestations. 50 systemic lupus erythematosus patients [25 with cutaneous manifestations (group I), 25 without cutaneous manifestations (group II)] and 20 normal controls (group III) were studied. Assessments of disease activity, peripheral lymphocyte apoptosis, macrophage function and apoptotic cells in skin and renal biopsies were carried out. The mean systemic lupus erythematosus disease activity index score was significantly higher in group I than II (18.6 +/- 6, 8.8 +/- 2.7 respectively, p < 0.001). The mean percentage of peripheral apoptotic lymphocytes was significantly higher in group I than groups II, III (55.3 +/- 21.4, 25.6 +/- 8.7 & 19.4 +/- 3.2 respectively, P < 0.001), so was serum neopterin level (27.5 +/- 7.3, 14.9 +/- 2.7, 9.4 +/- 1.1 respectively, p < 0.001), and the mean number of protein53 positive apoptotic keratinocytes in skin (20.6 +/- 5.4, 1.6 +/- 0.5, 1.7 +/- 0.4 respectively, p < 0.001). A higher percentage of class IV, V glomerulonephritis was found in group I (47%, 26%, respectively) compared to group II (11% both) (p < 0.001). The mean number of protein53 positive apoptotic skin keratinocytes showed a significant positive correlation to disease activity, percentage of peripheral apoptotic lymphocytes and serum neopterin (P < 0.001). In conclusion, an accumulation of apoptotic keratinocytes and lymphocytes in systemic lupus erythematosus with cutaneous manifestations is associated with a worse disease outcome.

Extrapolating In Vitro Screening Assay Data for Thyroperoxidase Inhibition to Predict Serum Thyroid Hormones in the Rat.

Thyroperoxidase (TPO) is an enzyme essential for thyroid hormone (TH) synthesis and a target site for a number of xenobiotics that disrupt TH homeostasis. An in vitro high-throughput screening assay for TPO inhibition, the Amplex UltraRed-TPO (AUR-TPO), has been used to screen the ToxCast chemical libraries for this action. Output from this assay would be most useful if it could be readily translated into an in vivo response, namely a reduction of TH in serum. To this end, the relationship between TPO inhibition in vitro and serum TH decreases was examined in rats exposed to 2 classic TPO inhibitors, propylthiouracil (PTU) and methimazole (MMI). Serum and gland PTU, MMI, and TH levels were quantified using tandem liquid chromatography mass spectrometry. Thyroperoxidase activity was determined in thyroid gland microsomes treated with PTU or MMI in vitro and ex vivo from thyroid gland microsomes prepared from exposed animals. A quantitative model was constructed by contrasting in vitro and ex vivo AUR-TPO results and the in vivo time-course and dose-response analysis. In vitro:ex vivo correlations of AUR-TPO outputs indicated that less than 30% inhibition of TPO in vitro was sufficient to reduce serum T4 by 20%, a degree of regulatory significance. Although further testing of model estimates using other TPO inhibitors is essential for verification of these initial findings, the results of this study provide a means to translate in vitro screening assay results into predictions of in vivo serum T4 changes to inform risk assessment.