Aims
To determine the prevalence of inflammatory back pain (IBP) and radiographic axial spondyloarthritis (SpA) in a semi‐urban community of Lahore, Pakistan.
Methods
This cross‐sectional household ...survey was designed as per the Community Oriented Program for the Control of Rheumatic Diseases (COPCORD) model. In Phase 1, the subjects were interviewed for musculoskeletal (MSK) pain in the last 7 days by clinical assistants. In Phase 2, physiotherapists identified subjects with spinal/back pain and interviewed for Assessment in Spondyloarthritis International Working Group (ASAS) criteria for IBP. In Phase 3 subjects having IBP or chronic back pain (CBP) with an age at onset ≤45 years, were assessed and further investigated.
Results
A total of 4922 subjects with a mean age of 35.3 ± 14.5 years, including 2770 (56%) women were surveyed in Phase 1. MSK pain in last 7 days was reported by 1407 (28.6%) of whom 1034 (21%) had spinal pain. The ASAS criteria for IBP were met in 329 (6.7%, 95% CI 6.0‐7.0). In Phase 3, 222 with IBP and 83 having CBP with age at onset ≤45 years were evaluated. Out of this total of 305, 144 (2.9%) were confirmed to have IBP by rheumatologists as per at least 1 of the 3 criteria. ASAS criteria were met in 107 (2.2%, 95% CI 1.8‐2.6). ASAS criteria for radiographic axial SpA were met in 47 (1%, 95% CI 0.7‐1.3) of the surveyed population.
Conclusion
Inflammatory back pain was reported in 6.7% by physiotherapists, confirmed in 3% by rheumatologists. The prevalence of radiographic axial SpA was 1%.
Cigarette smoke (CS) induces a rapid, sustained upregulation of ceramide production in human bronchial epithelial cells, leading to increased apoptosis. Using loss-of-function and overexpression ...analyses, we show that neutral sphingomyelinase 2 (nSMase2) is required for CS-mediated ceramide generation and apoptosis. Glutathione (GSH), a crucial antioxidant in lung defense, blocks nSMase2 activity and thus inhibits apoptosis triggered by CS. We found that the exposure to CS, as with exposure to H(2)O(2), results in increased nSMase2 activation leading to ceramide generation and therefore increased apoptosis. Interestingly, exposure of cells to GSH abolishes nSMase2 activation caused by CS and leads to a decrease in CS-induced apoptosis. This suggests that the effects of CS oxidants on nSMase2 are counteracted by GSH. Our data support a model where CS induces nSMase2 activation thereby increasing membrane-sphingomyelin hydrolysis to ceramide. In turn, elevated ceramide enhances airway epithelial cell death, which causes bronchial and alveolar destruction and lung injury in pulmonary diseases.
Despite their large numbers and widespread use, very little is known about the extent to which per- and polyfluoroalkyl substances (PFAS) can cross the placenta and expose the developing fetus.
The ...aim of our study is to develop a computational approach that can be used to evaluate the of extend to which small molecules, and in particular PFAS, can cross to cross the placenta and partition to cord blood.
We collected experimental values of the concentration ratio between cord and maternal blood (R
) for 260 chemical compounds and calculated their physicochemical descriptors using the cheminformatics package Mordred. We used the compiled database to, train and test an artificial neural network (ANN). And then applied the best performing model to predict R
for a large dataset of PFAS chemicals (n = 7982). We, finally, examined the calculated physicochemical descriptors of the chemicals to identify which properties correlated significantly with R
.
We determined that 7855 compounds were within the applicability domain and 127 compounds are outside the applicability domain of our model. Our predictions of R
for PFAS suggested that 3623 compounds had a log R
> 0 indicating preferable partitioning to cord blood. Some examples of these compounds were bisphenol AF, 2,2-bis(4-aminophenyl)hexafluoropropane, and nonafluoro-tert-butyl 3-methylbutyrate.
These observations have important public health implications as many PFAS have been shown to interfere with fetal development. In addition, as these compounds are highly persistent and many of them can readily cross the placenta, they are expected to remain in the population for a long time as they are being passed from parent to offspring.
Understanding the behavior of chemicals in the human body during pregnancy is critical in preventing harmful exposures during critical periods of development. Many chemicals can cross the placenta and expose the fetus, however, the mechanism by which this transport occurs is not well understood. In our study, we developed a machine learning model that describes the transplacental transfer of chemicals as a function of their physicochemical properties. The model was then used to make predictions for a set of 7982 per- and polyfluorinated alkyl substances that are listed on EPA's CompTox Chemicals Dashboard. The model can be applied to make predictions for other chemical categories of interest, such as plasticizers and pesticides. Accurate predictions of R
can help scientists and regulators to prioritize chemicals that have the potential to cause harm by exposing the fetus.
Chronic obstructive pulmonary disease (COPD) is caused by exposure to cigarette smoke (CS). One mechanism of CS-induced lung injury is aberrant generation of ceramide, which leads to elevated ...apoptosis of epithelial and endothelial cells in the alveolar spaces. Recently, we discovered that CS-induced ceramide generation and apoptosis in pulmonary cells is governed by neutral sphingomyelinase (nSMase) 2. In the current experiments, we expanded our studies to investigate whether nSMase2 governs ceramide generation and apoptosis in vivo using rodent and human models of CS-induced lung injury. We found that exposure of mice or rats to CS leads to colocalizing elevations of ceramide levels and terminal deoxynucleotidyl transferase mediated X-dUTP nick end labeling-positive cells in lung tissues. These increases are nSMase2 dependent, and are abrogated by treatment with N-acetyl cysteine or anti-nSMase2 small interfering RNA (siRNA). We further showed that mice that are heterozygous for nSMase2 demonstrate significant decrease in ceramide generation after CS exposure, whereas acidic sphingomyelinase (aSMase) knockout mice maintain wild-type ceramide levels, confirming our previous findings (in human airway epithelial cells) that only nSMase2, and not aSMase, is activated by CS exposure. Lastly, we found that lung tissues from patients with emphysema (smokers) display significantly higher levels of nSMase2 expression compared with lung tissues from healthy control subjects. Taken together, these data establish the central in vivo role of nSMase2 in ceramide generation, aberrant apoptosis, and lung injury under CS exposure, underscoring its promise as a novel target for the prevention of CS-induced airspace destruction.
The aryl hydrocarbon receptor (AhR) is involved in the regulation of immune responses, T-cell differentiation, and immunity. Here, we show that inflammatory stimuli such as LPS induce the expression ...of AhR in human dendritic cells (DC) associated with an AhR-dependent increase of CYP1A1 (cytochrome P4501A1). In vivo data confirmed the elevated expression of AhR by LPS and the LPS-enhanced 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-mediated induction of CYP1A1 in thymus of B6 mice. Inhibition of nuclear factor-κB (NF-κB) repressed both normal and LPS-enhanced, TCDD-inducible, AhR-dependent gene expression and canonical pathway control of RelA-regulated AhR-responsive gene expression. LPS-mediated induction of AhR was NF-κB-dependent, as shown in mouse embryonic fibroblasts (MEFs) derived from Rel null mice. AhR expression and TCDD-mediated induction of CYP1A1 was significantly reduced in RelA-deficient MEF compared with wild type MEF cells and ectopic expression of RelA restored the expression of AhR and induction of CYP1A1 in MEF RelA null cells. Promoter analysis of the human AhR gene identified three putative NF-κB-binding elements upstream of the transcription start site. Mutation analysis of the AhR promoter identified one NF-κB site as responsible for mediating the induction of AhR expression by LPS and electrophoretic shift assays demonstrated that this NF-κB motif is recognized by the RelA/p50 heterodimer. Our results show for the first time that NF-κB RelA is a critical component regulating the expression of AhR and the induction of AhR-dependent gene expression in immune cells illustrating the interaction of AhR and NF-κB signaling.
Background: Aryl hydrocarbon receptor (AhR) is a protein regulating differentiation and function of immune cells.
Results: NF-κB activates transcription of AhR and enhances activity of AhR-regulated genes.
Conclusion: Activation of NF-κB involves RelA-mediated expression of AhR.
Significance: Inflammatory stimuli and cytokines that regulate NF-κB induce AhR expression during activation and differentiation of immune cells.
Reporter genes produce a protein product in transfected cells that can be easily measured in intact or lysed cells and they have been extensively used in numerous basic and applied research ...applications. Over the past 10 years, reporter gene assays have been widely accepted and used for analysis of 2,3,7,8-tetrachlorodibenzo-p-dioxin and related dioxin-like compounds in various types of matrices, such as biological, environmental, food and feed samples, given that high-resolution instrumental analysis techniques are impractical for large-scale screening analysis. The most sensitive cell-based reporter gene bioassay systems developed are the mechanism-based CALUX (Chemically Activated Luciferase Expression) and CAFLUX (Chemically Activated Fluorescent Expression) bioassays, which utilize recombinant cell lines containing stably transfected dioxin (AhR)-responsive firefly luciferase or enhanced green fluorescent protein (EGFP) reporter genes, respectively. While the current CALUX and CAFLUX bioassays are very sensitive, increasing their lower limit of sensitivity, magnitude of response and dynamic range for chemical detection would significantly increase their utility, particularly for those samples that contain low levels of dioxin-like HAHs (i.e., serum). In this study, we report that the addition of modulators of cell signaling pathways or modification of cell culture conditions results in significant improvement in the magnitude and overall responsiveness of the existing CALUX and CAFLUX cell bioassays.
Objective: To determine the clinical and laboratory features during the disease course in patients of anti cytoplasmic antibody (ANCA) associated vasculitis in Pakistani patients presenting to a ...tertiary care center. Study Design: Case series. Place and Duration of Study: Fatima Memorial Hospital Shadman Lahore, from Dec 2018 to Mar 2019. Methodology: A collection of 20 patients regarding demographic data, constitutional symptoms, mucocutaneous symptoms and signs, upper respiratory symptoms, lower respiratory symptoms, orbital and ocular manifestation, cardiovascular, peripheral vascular manifestation, central and peripheral neurologic manifestation, abdominal manifestation and renal manifestation Results: Sixteen patients (80%) had a diagnosis of Granulomatosis with Polyangiitis, and 4 patients (20%) were of microscopic polyangiitis. The most common systemic involvement in descending order were constitutional symptoms (75%), ear nose and throat symptoms (50%), renal (50%), respiratory (45%), ocular (40%) and neurologic (40%). Most common laboratory abnormalities in our patients included leukocytosis (45%), anemia (35%), hematuria (50%), proteinuria (45%), and elevated serum creatinine (45%). Cytoplasmic-anti cytoplasmic antibody (C-ANCA) was positive in 11 (55%), all cases were of granulomatosis with polyangiitis, P-ANCA was positive in 5 (25%) of all patients, with 4 (100%) in Microscopic polyangiitis. Analysis of Granulomatosis with Polyangiitis according to gender and cytoplasmic-anti cytoplasmic antibody status showed correlation of renal involvement with cytoplasmic-anti cytoplasmic antibody status with statistical significance of p=0.036. Plain chest X-rays showed infiltrates in 2 (10%), nodularity 2 (10%), cavitation in 2 (10%), effusion in 1 (5%), and reticulonodular showing in 1 (5%) patients. High-resolution computed tomography findings included ground-glass opacification in 5...
Recent crystallographic studies have offered a new understanding of how receptor tyrosine kinases from the ErbB family are regulated by their growth factor ligands. A large conformational change was ...shown to occur upon ligand binding, where a solely receptor‐mediated mode of dimerization was documented. We have shown that oxidative stress, in the form of H2O2, activates the epidermal growth factor (EGF) receptor (EGFR, ErbB1) in human airway epithelial cells differently than its ligand, EGF. Most notably, H2O2 activation of the EGFR resulted in aberrant phosphorylation as well as impaired trafficking and degradation of the receptor, which leads to hyperplasia. Using various biochemical techniques, we now demonstrate that H2O2 activation of the EGFR is ligand‐independent and does not induce receptor dimerization in the same manner as EGF. Interestingly, H2O2−induced phosphorylation of the EGFR is not inhibited by the EGFR kinase inhibitors AG1478 and AG1517, which may negatively impact therapies targeting the kinase domain. Furthermore, H2O2 activation of the EGFR is temperature‐dependent and is inhibited by the addition of cholesterol, suggesting that activation by H2O2 is dependent upon membrane fluidity. Overall, our findings indicate that H2O2 activation of the EGFR does not fit the current paradigm of activation by EGF. By combining the information gained from the recent biochemical studies, we hope to develop models for the allosteric regulation of the EGFR under oxidative stress. These models will greatly improve our understanding of ErbB receptor signaling under oxidative stress, which will generate opportunities for the design of new anticancer agents.
Background: Hydroxychloroquine (HCQ) an anti-inflammatory drug used in treatment of rheumatic diseases causes retinal toxicity in a minority of patients which are both time and dose dependent. The ...aim of this study was to assess the compliance with guidelines of American Association of Ophthalmology for screening and dosage of this drug.
Patients and methods: In this cross-sectional analysis, the medical records of patients who were on HCQ, attending Rheumatology Outpatient Department of Fatima Memorial Hospital Shadman, Lahore from 25-05-2019 to 30-05-2019 were reviewed. The dosage and, duration of HCQ were collected, files were reviewed for physician recommendation of screening tests for retinal toxicity. HCQ dose of 5mg/kg/day was labeled as adequate dose; dose below 4.5mg/kg/day under dosed, while dose of 6mg/kg/day and above was considered overdose.
Results: Data was collected from 81 patients during the study period, 74 (91.4%) of them being female, with mean age 35.15 ± 12.6 years. Based on total body weight, 23 patients (28.4%) were receiving the correct dosage of the drug around 5mg/kg/day whereas 39 (48.1%) patients were under-dosed below 4.5mg/kg/day, and 19 patients (23.5%) were over dosed, out of which 5 (6.17%) were receiving doses above 6.5mg/kg. Baseline eye screening examination by ophthalmologist was performed within 1 year of commencing treatment in 54 (66%) patients. Of the 27 patients receiving HCQ more than 5 years, 6 patients underwent Spectral coherence Ocular CT scan (SD-OCT) evaluation at 5 years. There was minimal compliance (less than 70% of Patients) to optimum drug dosage, partial compliance (70-89% patients) to preventing over-dosage of the drug, and full compliance (more than 90% patients) was achieved in baseline screening exam recommendation. Follow-up screening documentation and 5-years screening examination had minimal compliance.
Conclusion: A significant proportion of patients are underdosed, especially the obese population where the recommended dosage is not prescribed.
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