19 results on '"Meyer PWA"'
Search Results
2. Human leukocyte antigen (HLA) diversity and clinical applications in South Africa
- Author
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Mellet, J, primary, Tshabalala, M, additional, Agbedare, O, additional, Meyer, PWA, additional, Gray, C M, additional, and Pepper, M S, additional
- Published
- 2019
- Full Text
- View/download PDF
3. Biomarkers and genes predictive of disease predisposition and prognosis in rheumatoid arthritis
- Author
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Meyer, PWA
- Abstract
No Abstract.
- Published
- 2012
4. Beta-2 microglobulin as a predictor of peripheral arterial disease in diabetes: the effect of estimated glomerular filtration
- Author
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Rheeder, P, primary, Nel, L, additional, Meeuwes, F, additional, Van Schendel, M, additional, and Meyer, PWA, additional
- Published
- 2012
- Full Text
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5. Functional disability and health-related quality of life in South Africans with early rheumatoid arthritis
- Author
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Hodkinson, B, primary, Musenge, E, additional, Ally, M, additional, Meyer, PWA, additional, Anderson, R, additional, and Tikly, M, additional
- Published
- 2012
- Full Text
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6. Transforming growth factor-β1 and soluble co-inhibitory immune checkpoints as putative drivers of immune suppression in patients with basal cell carcinoma.
- Author
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Kgokolo MCM, Malinga NZ, Steel HC, Meyer PWA, Smit T, Anderson R, and Rapoport BL
- Abstract
The current study compared the levels and possible associations between systemic soluble immune checkpoints (sICPs, n = 17) and a group of humoral modulators of immune suppressor cells (n = 7) in a cohort of patients with basal cell carcinoma (BCC, n = 40) and a group of healthy control subjects (n = 20). The seven humoral modulators of immunosuppressor cells were represented by the enzymes, arginase 1 and fibroblast activation protein (FAP), the chemokine, RANTES (CCL5) and the cytokines, interleukin-10 and transforming growth factor-β1 (TGF-β1), as well as the M2-type macrophage markers, soluble CD163 (sCD163) and sCD206. The plasma levels of six co-inhibitory sICPs, sCTLA-4, sLAG-3, sPD-1, sPD-L1, sTIM-3 and sPD-L2 were significantly elevated in the cohort of BCC patients (p<0.001-p<0.00001), while that of sBTLA was significantly decreased (p<0.006). Of the co-stimulatory sICPs, sCD27 and sGITR were significantly increased (p<0.0002 and p<0.0538) in the cohort of BCC patients, while the others were essentially comparable with those of the control participants; of the dual active sICPs, sHVEM was significantly elevated (p<0.00001) and TLR2 comparable with the control group. A correlation heat map revealed selective, strong associations of TGF-β1 with seven co-stimulatory (z = 0.618468-0.768131) and four co-inhibitory (z = 0.674040-0.808365) sICPs, as well as with sTLR2 (z = 0.696431). Notwithstanding the association of BCC with selective elevations in the levels of a large group of co-inhibitory sICPs, our novel findings also imply the probable involvement of TGF-β1 in driving immunosuppression in this malignancy, possibly via activation of regulatory T cells. Notably, these abnormalities were present in patients with either newly diagnosed or recurrent disease., Competing Interests: Declaration of competing interest None of the authors has a conflict of interest to declare., (Copyright © 2024. Published by Elsevier Inc.)
- Published
- 2024
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7. Dysregulation of systemic soluble immune checkpoints in early breast cancer is attenuated following administration of neoadjuvant chemotherapy and is associated with recovery of CD27, CD28, CD40, CD80, ICOS and GITR and substantially increased levels of PD-L1, LAG-3 and TIM-3.
- Author
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Rapoport BL, Steel HC, Benn CA, Nayler S, Smit T, Heyman L, Theron AJ, Hlatshwayo N, Kwofie LLI, Meyer PWA, and Anderson R
- Abstract
Neoadjuvant chemotherapy (NAC) may alter the immune landscape of patients with early breast cancer (BC), potentially setting the scene for more effective implementation of checkpoint-targeted immunotherapy. This issue has been investigated in the current study in which alterations in the plasma concentrations of 16 soluble co-stimulatory and co-inhibitory, immune checkpoints were measured sequentially in a cohort of newly diagnosed, early BC patients (n=72), pre-treatment, post-NAC and post-surgery using a Multiplex
® bead array platform. Relative to a group of healthy control subjects (n=45), the median pre-treatment levels of five co-stimulatory (CD27, CD40, GITRL, ICOS, GITR) and three co-inhibitory (TIM-3, CTLA-4, PD-L1) soluble checkpoints were significantly lower in the BC patients vs. controls ( p <0.021- p <0.0001; and p <0.008- p <0.00001, respectively). Following NAC, the plasma levels of six soluble co-stimulatory checkpoints (CD28, CD40, ICOS, CD27, CD80, GITR), all involved in activation of CD8+ cytotoxic T cells, were significantly increased ( p <0.04- p <0.00001), comparable with control values and remained at these levels post-surgery. Of the soluble co-inhibitory checkpoints, three (LAG-3, PD-L1, TIM-3) increased significantly post-NAC, reaching levels significantly greater than those of the control group. PD-1 remained unchanged, while BTLA and CTLA-4 decreased significantly ( p <0.03 and p <0.00001, respectively). Normalization of soluble co-stimulatory immune checkpoints is seemingly indicative of reversal of systemic immune dysregulation following administration of NAC in early BC, while recovery of immune homeostasis may explain the increased levels of several negative checkpoint proteins, albeit with the exceptions of CTLA-4 and PD-1. Although a pathological complete response (pCR) was documented in 61% of patients (mostly triple-negative BC), surprisingly, none of the soluble immune checkpoints correlated with the pCR, either pre-treatment or post-NAC. Nevertheless, in the case of the co-stimulatory ICMs, these novel findings are indicative of the immune-restorative potential of NAC in early BC, while in the case of the co-inhibitory ICMs, elevated levels of soluble PD-L1, LAG-3 and TIM-3 post-NAC underscore the augmentative immunotherapeutic promise of targeting these molecules, either individually or in combination, as a strategy, which may contribute to the improved management of early BC., Competing Interests: Author SN is a partner at Drs Gritzman & Thatcher Inc. Laboratories. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Rapoport, Steel, Benn, Nayler, Smit, Heyman, Theron, Hlatshwayo, Kwofie, Meyer and Anderson.)- Published
- 2023
- Full Text
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8. Comparative upper-quarter posture analysis of female adolescent freestyle swimmers and non-swimmers.
- Author
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Botha CM, Rossouw F, Meyer PWA, and Camacho TCS
- Subjects
- Humans, Female, Cross-Sectional Studies, Photography methods, Posture physiology, Shoulder physiology, Upper Extremity
- Abstract
ABSTRACT Repetitive upper-quarter limb movements imposed by freestyle swimming may lead to muscle length and tension changes, predisposing adolescent swimmers to postural malalignment. The study aimed to quantify the static upper-quarter postural alignment of competitive female adolescent freestyle swimmers, and compare their results to non-swimming peers and angles of spinal sagittal posture available in the literature. A cross-sectional study design was employed. The evaluation group (EVAL) consisted of 35 competitive swimmers (15 ± 3 y; 166.5 ± 9.9 cm; 65.5 ± 7.7 kg) and the control group (CON) of 36 peers (15 ± 3 y; 164.2 ± 6.7 cm; 62.1 ± 9.1 kg). Spinal sagittal posture was measured by photographic posture analysis. Median ± interquartile range and inter-group differences were calculated. Significant differences ( p = 0.00) between groups for all variables, with a moderate - large effect, were observed. EVAL demonstrated restricted median scores for head-tilt angle (-8.7°), cervical angle (-13.3°) and shoulder protraction - retraction angle (-24°), and a greater score for thoracic angle (+7.4°), when compared to CON. EVAL and CON deviated from proposed criterion scores for cervical and thoracic angles, with EVAL also deviating from head-tilt angle and shoulder protraction - retraction angle criteria. In this group of adolescent participants, postural malalignment may have been exacerbated by years of freestyle swim training. HighlightsSignificant differences with medium to large effect sizes were noted in the angles of spinal sagittal posture between the competitive female adolescent freestyle swimmers and their non-swimming peers.Competitive female adolescent freestyle swimmers appeared to be more vulnerable to postural features in the upper quarter that were not within the desirable angles of spinal sagittal posture.The inherent nature of competitive freestyle swimming and the natural consequence of long-term training may explain the moderate to large effect sizes observed.
- Published
- 2023
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9. Pro-Inflammatory Interactions of Dolutegravir with Human Neutrophils in an In Vitro Study.
- Author
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Theron AJ, Anderson R, Madzime M, Rossouw TM, Steel HC, Meyer PWA, Cholo MC, Kwofie LLI, Feldman C, and Tintinger GR
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- Adult, Humans, Female, Reactive Oxygen Species metabolism, Neutrophils, Heterocyclic Compounds, 3-Ring pharmacology, Heterocyclic Compounds, 3-Ring metabolism, Pancreatic Elastase metabolism, Inflammation chemically induced, Inflammation drug therapy, Inflammation metabolism, HIV Infections drug therapy, HIV Infections metabolism, HIV Integrase Inhibitors pharmacology, HIV Integrase Inhibitors therapeutic use
- Abstract
There is increasing awareness of an association between the uptake of the HIV integrase inhibitor, dolutegravir, in first-line antiretroviral regimens with unusual weight gain and development of the metabolic syndrome, particularly in African women. Although seemingly unexplored, the development of systemic inflammation linked to the putative pro-inflammatory activity of dolutegravir represents a plausible pathophysiological mechanism of this unusual weight gain. This possibility was explored in the current study undertaken to investigate the effects of dolutegravir (2.5−20 μg/mL) on several pro-inflammatory activities of neutrophils isolated from the blood of healthy, adult humans. These activities included the generation of reactive oxygen species (ROS), degranulation (elastase release) and alterations in the concentrations of cytosolic Ca2+ using chemiluminescence, spectrophotometric and fluorimetric procedures, respectively. Exposure of neutrophils to dolutegravir alone resulted in the abrupt, dose-related, and significant (p < 0.0039−p < 0.0022) generation of ROS that was attenuated by the inclusion of the Ca2+-chelating agent, EGTA, or inhibitors of NADPH oxidase (diphenyleneiodonium chloride, DPI), phospholipase C (U733122), myeloperoxidase (sodium azide) and phosphoinositol-3-kinase (wortmannin). In addition, exposure to dolutegravir augmented the release of elastase by stimulus-activated neutrophils. These pro-inflammatory effects of dolutegravir on neutrophils were associated with significant, rapid, and sustained increases in the concentrations of cytosolic Ca2+ that appeared to originate from the extracellular compartment, seemingly consistent with an ionophore-like property of dolutegravir. These findings are preliminary and necessitate verification in the clinical setting of HIV infection. Nevertheless, given the complex link between inflammation and obesity, these pro-inflammatory interactions of dolutegravir with neutrophils may contribute to unexplained weight gain, possibly via the development of insulin resistance.
- Published
- 2022
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10. Dolutegravir potentiates platelet activation by a calcium-dependent, ionophore-like mechanism.
- Author
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Madzime M, Theron AJ, Anderson R, Tintinger GR, Steel HC, Meyer PWA, Nel JG, Feldman C, and Rossouw TM
- Subjects
- Adult, Humans, Thrombin pharmacology, 15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid pharmacology, Platelet Activation, Adenosine Diphosphate pharmacology, Ionophores pharmacology, Calcium, HIV Infections drug therapy
- Abstract
Dolutegravir is a highly potent HIV integrase strand transfer inhibitor that is recommended for first-line anti-retroviral treatment in all major treatment guidelines. A recent study has shown that people taking this class of anti-retroviral treatment have a substantially higher risk of early-onset cardiovascular disease, a condition shown previously to be associated with increased platelet reactivity. To date, few studies have explored the effects of dolutegravir on platelet activation. Accordingly, the current study was undertaken with the primary objective of investigating the effects of dolutegravir on the reactivity of human platelets in vitro. Platelet-rich plasma, isolated platelets, or buffy coat cell suspensions prepared from the blood of healthy adults were treated with dolutegravir (2.5-10 µg/ml), followed by activation with adenosine 5'-diphosphate (ADP), thrombin, or a thromboxane A
2 receptor agonist U46619. Expression of platelet CD62P (P-selectin), formation of heterotypic neutrophil:platelet aggregates, and calcium (Ca2+ ) fluxes were measured using flow cytometry and fluorescence spectrometry, respectively. Dolutegravir caused dose-related potentiation of ADP-, thrombin- and U46619-activated expression of CD62P by platelets, as well as a significant increases in formation of neutrophil:platelet aggregates. These effects were paralleled by a spontaneous, receptor-independent elevation in cytosolic Ca2+ that appears to underpin the mechanism by which the antiretroviral agent augments the responsiveness of these cells to ADP, thrombin and U46619. The most likely mechanism of dolutegravir-mediated increases in platelet cytosolic Ca2+ relates to a combination of lipophilicity and divalent/trivalent metal-binding and/or chelating properties of the anti-retroviral agent. These properties are likely to confer ionophore-type activities on dolutegravir that would promote movement of Ca2+ across the plasma membrane, delivering the cation to the cytosol where it would augment Ca2+ -dependent intracellular signaling mechanisms. These effects of dolutegravir may lead to hyper-activation of platelets which, if operative in vivo , may contribute to an increased risk for cardiometabolic co-morbidities.- Published
- 2022
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11. Decline in antibody responses to SARS-CoV-2 post-vaccination poses a risk to health care workers.
- Author
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Worsley CM, van der Mescht MA, Hoffmann D, Meyer PWA, Ueckermann V, and Rossouw TM
- Subjects
- Antibody Formation, Health Personnel, Humans, Vaccination adverse effects, COVID-19 prevention & control, SARS-CoV-2
- Abstract
Competing Interests: Declaration of interests None.
- Published
- 2022
- Full Text
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12. Systemic Immune Dysregulation in Early Breast Cancer Is Associated With Decreased Plasma Levels of Both Soluble Co-Inhibitory and Co-Stimulatory Immune Checkpoint Molecules.
- Author
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Rapoport BL, Steel HC, Hlatshwayo N, Theron AJ, Meyer PWA, Nayler S, Benn CA, Smit T, Kwofie LLI, Heyman L, and Anderson R
- Subjects
- Chemokine CCL5 blood, Female, Humans, Macrophage Colony-Stimulating Factor blood, Breast Neoplasms immunology, Breast Neoplasms physiopathology, Immune Checkpoint Proteins blood
- Abstract
Breast cancer cells exploit the up-regulation or down-regulation of immune checkpoint proteins to evade anti-tumor immune responses. To explore the possible involvement of this mechanism in promoting systemic immunosuppression, the pre-treatment levels of soluble co-inhibitory and co-stimulatory immune checkpoint molecules, as well as those of cytokines, chemokines, and growth factors were measured in 98 newly diagnosed breast cancer patients and compared with those of 45 healthy controls using multiplex bead array and ELISA technologies. Plasma concentrations of the co-stimulatory immune checkpoints, GITR, GITRL, CD27, CD28, CD40, CD80, CD86 and ICOS, as well as the co-inhibitory molecules, PD-L1, CTLA-4 and TIM-3, were all significantly lower in early breast cancer patients compared to healthy controls, as were those of HVEM and sTLR-2, whereas the plasma concentrations of CX3CL1 (fractalkine), CCL5 (RANTES) and those of the growth factors, M-CSF, FGF-21 and GDF-15 were significantly increased. However, when analyzed according to the patients' breast cancer characteristics, these being triple negative breast cancer (TNBC) vs. non-TNBC, tumor size, stage, nodal status and age, no significant differences were detected between the plasma levels of the various immune checkpoint molecules, cytokines, chemokines and growth factors. Additionally, none of these biomarkers correlated with pathological complete response. This study has identified low plasma levels of soluble co-stimulatory and co-inhibitory immune checkpoint molecules in newly diagnosed, non-metastatic breast cancer patients compared to healthy controls, which is a novel finding seemingly consistent with a state of systemic immune dysregulation. Plausible mechanisms include an association with elevated levels of M-CSF and CCL5, implicating the involvement of immune suppressor cells of the M2-macrophage/monocyte phenotype as possible drivers of this state of systemic immune quiescence/dysregulation., Competing Interests: Author SN is a partner at Drs Gritzman & Thatcher Inc. Laboratories. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Rapoport, Steel, Hlatshwayo, Theron, Meyer, Nayler, Benn, Smit, Kwofie, Heyman and Anderson.)
- Published
- 2022
- Full Text
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13. Systemic levels of the soluble co-inhibitory immune checkpoints, CTLA-4, LAG-3, PD-1/PD-L1 and TIM-3 are markedly increased in basal cell carcinoma.
- Author
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Malinga NZ, Siwele SC, Steel HC, Kwofie LLI, Meyer PWA, Smit T, Anderson R, Rapoport BL, and Kgokolo MCM
- Abstract
Although co-inhibitory immune checkpoint proteins are primarily involved in promoting cell-cell interactions that suppress adaptive immunity, especially tumor immunity, the soluble cell-free variants of these molecules are also detectable in the circulation of cancer patients where they retain immunosuppressive activity. Nevertheless, little is known about the systemic levels of these soluble co-inhibitory immune checkpoints in patients with various subtypes of basal cell carcinoma (BCC), which is the most invasive and treatment-resistant type of this most commonly-occurring malignancy. In the current study, we have measured the systemic concentrations of five prominent co-inhibitory immune checkpoints, namely CTLA-4, LAG-3, PD-1/PD-L1 and TIM-3, as well as those of C-reactive protein (CRP) and vitamin D (VD), in a cohort of patients (n = 40) with BCC, relative to those of a group of control participants, using the combination of multiplex bead array, laser nephelometry and ELISA technologies, respectively. The median systemic concentrations of CRP and VD were comparable between the two groups; however, those of all five immune checkpoints were significantly elevated (P = 0.0184 - P = < 0.00001), with those of CTLA-4 and PD-1 being highly correlated (r = 0.87; P < 0.00001). This seemingly novel finding not only identifies the existence of significant systemic immunosuppression in BCC, but also underscores the therapeutic promise of immune checkpoint targeted therapy, as well as the potential of these proteins to serve as prognostic/predictive biomarkers in BCC., (Copyright © 2022. Published by Elsevier Inc.)
- Published
- 2022
- Full Text
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14. Elevated Levels of Soluble CTLA-4, PD-1, PD-L1, LAG-3 and TIM-3 and Systemic Inflammatory Stress as Potential Contributors to Immune Suppression and Generalized Tumorigenesis in a Cohort of South African Xeroderma Pigmentosum Patients.
- Author
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Kgokolo MCM, Anderson K, Siwele SC, Steel HC, Kwofie LLI, Sathekge MM, Meyer PWA, Rapoport BL, and Anderson R
- Abstract
Xeroderma Pigmentosum (XP), an autosomal recessive disorder characterized by ultraviolet radiation-induced abnormalities of DNA excision and repair pathways is associated with early development of cutaneous cancers. Intracellular oxidative stress has also been proposed as a contributor to the occurrence of skin cancers. However, little is known about the possible augmentative contributions of chronic inflammation, immune suppression and oxidative stress to the pathogenesis of malignancies associated with other subtypes of XP. This has been addressed in the current study, focused on the measurement of systemic biomarkers of inflammation, immune dysfunction and oxidative damage in XP patients, consisting of XP-C, XP-D and XP-E cases, including those XP-C cases who had already developed multiple skin malignancies. The inflammatory biomarker profile measured in XP patients and healthy control subjects included the cytokines, interleukins (ILs)-2, -4, -6, -10, interferon-γ (IFN- γ) and tumor-necrosis factor-α (TNF-α), the acute phase reactant, C-reactive protein (CRP), and cotinine (as an objective indicator of smoking status). Immune suppression was detected according to the levels of five soluble inhibitory immune checkpoint proteins (CTLA-4, PD-1, PD-L1, LAG-3 and TIM-3), as well as those of vitamin D, while oxidative stress was determined according to the circulating levels of the DNA adduct, 8-hydroxy-2-deoxyguanosine (8-OH-dG). These various biomarkers were measured in plasma using immunofluorimetric, nephelometric and ELISA procedures. Significant elevations in IL-6 ( P <0.01) and TNF-α ( P <0.0001), but none of the other cytokines, as well as increased levels of all five soluble inhibitory immune checkpoints ( P =0.032- P =0.0001) were detected in the plasma of the XP patients. C-reactive protein and vitamin D were increased and decreased, respectively (both P <0.0001), while only one participant had an elevated level of plasma cotinine. Surprisingly, the levels of 8-OH-dG were significantly ( P =0.0001) lower in the group of XP patients relative to a group of healthy control subjects. The findings of increased levels of pro-inflammatory cytokines and, in particular, those of the soluble immune checkpoints, in the setting of decreased vitamin D and moderately elevated levels of CRP in XP patients suggest a possible secondary role of ongoing, inflammatory stress and immune suppression in the pathogenesis of XP-associated malignancies., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Kgokolo, Anderson, Siwele, Steel, Kwofie, Sathekge, Meyer, Rapoport and Anderson.)
- Published
- 2022
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15. Simple Erosion Narrowing Score of the hands as a predictor of cervical spine subluxation in rheumatoid arthritis.
- Author
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Gous E, Ally MMTM, Meyer PWA, and Suleman FE
- Abstract
Background: Involvement of the cervical spine is common in patients with rheumatoid arthritis and can lead to devastating or even fatal consequences. Currently no guidelines exist as to whether radiographs of the cervical spine should be included in follow-up visits., Objectives: To determine whether the Simple Erosion Narrowing Score (SENS) of the hands correlate with the presence of cervical spine subluxation in patients with rheumatoid arthritis., Method: This was a retrospective, observational, cross-sectional study. A total of 56 rheumatoid arthritis patients with hand radiographs and lateral radiographs of the cervical spine were evaluated. The SENS of the hands and the presence of cervical spine subluxation were compared. The SENS of the hands was correlated with the prevalence of cervical spine subluxation, as was the erosion and joint space narrowing scores of the hands., Results: A correlation between the SENS of the hands and the prevalence of cervical spine subluxation was confirmed. A higher prevalence of cervical spine subluxation correlated with an increase in the SENS of the hands ( p = 0.0002). The erosion and joint space narrowing scores of the hands also correlated with the prevalence of cervical spine subluxation ( p = 0.0001)., Conclusion: This study confirmed that a correlation exists between cervical spine subluxation, peripheral joint space erosions and joint space narrowing in patients with rheumatoid arthritis and SENS may therefore be used as a predictor of cervical spine disease., Competing Interests: The authors have declared that no competing interests exist., (© 2020. The Authors.)
- Published
- 2020
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16. Tobacco-Derived Lipopolysaccharide, Not Microbial Translocation, as a Potential Contributor to the Pathogenesis of Rheumatoid Arthritis.
- Author
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Meyer PWA, Ally MMTM, Tikly M, Tintinger G, Winchow LL, Steel H, and Anderson R
- Subjects
- Arthritis, Rheumatoid blood, Biomarkers blood, Biomarkers metabolism, C-Reactive Protein metabolism, Enzyme-Linked Immunosorbent Assay, Fatty Acid-Binding Proteins metabolism, Female, Humans, Male, Rheumatoid Factor metabolism, Nicotiana chemistry, Arthritis, Rheumatoid chemically induced, Lipopolysaccharides chemistry
- Abstract
Microbial lipopolysaccharides (LPS) have been implicated in the pathogenesis of rheumatoid arthritis (RA), possibly driving a systemic inflammatory response that may trigger the development and/or exacerbation of the disease. To explore the existence of this mechanism in African RA patients, we have measured systemic levels of LPS and its surrogate, LPS-binding protein (LBP), as well as those of intestinal fatty acid-binding protein (I-FABP), pulmonary surfactant protein D (SP-D), and cotinine in serum to identify possible origins of LPS, as well as associations of these biomarkers with rheumatoid factor (RF) and anticitrullinated peptide (aCCP) autoantibodies and the DAS 28-3 clinical disease severity score. A cohort of 40 disease-modifying antirheumatic drug-naïve, black South African RA patients rated by compound disease scores and 20 healthy subjects and 10 patients with chronic obstructive pulmonary disease (COPD) as controls were included in this study. Levels of the various biomarkers and autoantibodies were measured using a combination of ELISA and immunofluorimetric and immunoturbidometric procedures. LPS levels were lowest in the RA group compared to the healthy controls ( p = 0.026) and COPD patients ( p = 0.017), while LBP levels were also significantly lower in RA compared to the healthy individuals ( p = 0.036). Levels of I-FABP and SP-D were comparable between all three groups. Categorisation of RA patients according to tobacco usage revealed the following significant positive correlations: LBP with C-reactive protein ( p = 0.0137); a trend ( p = 0.073) towards an association of LBP with the DAS 28-3 disease severity score; RF-IgG antibodies with both LPS and LBP ( p = 0.033 and p = 0.041, respectively); aCCP-IgG antibodies with LPS ( p = 0.044); and aCCP-IgG with RF-IgM autoantibodies ( p = 0.0016). The findings of this study, several of them novel, imply that tobacco products, as opposed to microbial translocation, represent a potential source of LPS in this study cohort of RA patients, again underscoring the risks posed by tobacco usage for the development and severity of RA., Competing Interests: The authors declare that there is no conflict of interest regarding the publication of this paper., (Copyright © 2019 Pieter W. A. Meyer et al.)
- Published
- 2019
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17. Interleukin-10 and interleukin-1 receptor antagonist distinguish between patients with sepsis and the systemic inflammatory response syndrome (SIRS).
- Author
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Potjo M, Theron AJ, Cockeran R, Sipholi NN, Steel HC, Bale TV, Meyer PWA, Anderson R, and Tintinger GR
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- Adult, Biomarkers blood, Diagnosis, Differential, Female, Humans, Inflammation blood, Male, Predictive Value of Tests, ROC Curve, Sensitivity and Specificity, Sepsis microbiology, Sepsis mortality, Survivors, Systemic Inflammatory Response Syndrome mortality, Interleukin 1 Receptor Antagonist Protein blood, Interleukin-10 blood, Sepsis blood, Sepsis diagnosis, Systemic Inflammatory Response Syndrome blood, Systemic Inflammatory Response Syndrome diagnosis
- Abstract
The current study evaluated the potential of clinical parameters and circulating biomarkers to distinguish sepsis from SIRS in patients admitted with systemic inflammation. Clinical parameters, leukocyte counts and platelets were measured on admission. Circulating C-reactive protein (CRP), procalcitonin (PCT) and cytokine concentrations were quantified using laser immunonephelometry, immunoluminescence and a Bio-Plex suspension bead array system respectively. Blood, sputum, urine, peritoneal and cerebrospinal fluid were sent for microscopy and culture. Based on clinical information and the results of microbiological testing, 62 patients were classified retrospectively into 2 groups, those with sepsis (n = 37) or SIRS (n = 25). Mean body temperature was higher and blood pressure lower in the sepsis patients. Circulating concentrations of CRP, PCT, interleukin (IL)-10 and IL-1 receptor antagonist (IL-1Ra) were significantly higher in patients with sepsis, with IL-10 identified as the best biomarker in differentiating sepsis from SIRS. The biomarkers that best predicted overall mortality were platelet counts >PCT ≥ CRP > IL-6 > IL-1Ra. These findings demonstrate that patients with sepsis have significantly increased levels of the immunosuppressive/anti-inflammatory cytokines, IL-1Ra and IL-10, compared to those with SIRS, consistent with a more intense counteracting anti-inflammatory response, while a biomarker profile including platelets, PCT, CRP, IL-6 and IL-1Ra may be useful to predict mortality., (Copyright © 2019 Elsevier Ltd. All rights reserved.)
- Published
- 2019
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18. Dilute Russel Viper Venom Time analysis in a Haematology Laboratory: An audit.
- Author
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Kruger W, Meyer PWA, and Nel JG
- Subjects
- Blood Coagulation Tests, Cross-Sectional Studies, False Negative Reactions, Humans, Practice Guidelines as Topic, Prothrombin Time economics, Workflow, Hematology methods, Prothrombin Time standards
- Abstract
Introduction: To determine whether the current set of evaluation criteria used for dilute Russel Viper Venom Time (dRVVT) investigations in the routine laboratory meet expectation and identify possible shortcomings., Methods: All dRVVT assays requested from January 2015 to December 2015 were appraised in this cross-sectional study. The raw data panels were compared with the new reference interval, established in 2016, to determine the sequence of assays that should have been performed. The interpretive comments were audited, and false-negative reports identified. Interpretive comments according to three interpretation guidelines were compared. The reagent cost per assay was determined, and reagent cost wastage, due to redundant tests, was calculated., Results: Only ~9% of dRVVT results authorized during 2015 had an interpretive comment included in the report. ~15% of these results were false-negative interpretations. There is a significant statistical difference in interpretive comments between the three interpretation methods. Redundant mixing tests resulted in R 7477.91 (~11%) reagent cost wastage in 2015., Conclusions: We managed to demonstrate very evident deficiencies in our own practice and managed to establish a standardized workflow that will potentially render our service more efficient and cost effective, aiding clinicians in making improved treatment decisions and diagnoses. Furthermore, it is essential that standard operating procedures be kept up to date and executed by all staff in the laboratory., (© 2018 John Wiley & Sons Ltd.)
- Published
- 2018
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19. Comparison of the diagnostic potential of three anti-citrullinated protein antibodies as adjuncts to rheumatoid factor and CCP in a cohort of South African rheumatoid arthritis patients.
- Author
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Meyer PWA, Ally MTM, Hodkinson B, Anderson R, and Tikly M
- Subjects
- Adult, Arthritis, Rheumatoid diagnosis, Arthritis, Rheumatoid immunology, Autoantibodies blood, Biomarkers blood, Diagnosis, Differential, Female, Humans, Male, Middle Aged, Retrospective Studies, South Africa, Anti-Citrullinated Protein Antibodies blood, Arthritis, Rheumatoid blood, Rheumatoid Factor blood
- Abstract
Purpose: A retrospective comparison of the prevalence and diagnostic value of anti-Sa, anti-CEP-1, and anti-MCV autoantibodies relative to those of the established autoantibodies, composite RF and anti-CCP-IgG used routinely for RA diagnosis as a component of the ACR 2010 criteria, in a cohort of disease-modifying anti-rheumatic drug naïve African RA patients (n = 75)., Methods: Serum concentrations of anti-Sa, anti-CEP-1 and anti-MCV autoantibodies were measured using ELISA procedures, while anti-CCP-IgG antibodies were determined by fluorescence enzyme immunoassay, and composite RF by latex-enhanced laser nephelometry., Results: The seropositivity frequencies of anti-Sa, anti-CEP-1 and anti-MCV antibodies for the RA patients were 82, 72, 85%, respectively, while that of anti-CCP-IgG and RF was 87% for both. Overall, anti-MCV demonstrated the best specificity, positive predictive value (PPV), odds ratio and positive likelihood ratio of all the types of autoantibody tested., Conclusion: These observations in this unique cohort of RA patients indicated novel associations of all three autoantibodies in regard to HLA-SE risk alleles, disease severity and tobacco use that were not reported before. Elevated anti-Sa titers designated a propensity of higher disease and high-risk alleles in our cohort. Anti-CEP-1 association with HLA-SE homozygosity and high-risk alleles is also novel in this group. Of note, measurement of anti-MCV antibodies on presentation, either as an adjunctive or even as a stand-alone test, surpassed all other biomarkers investigated here and, therefore, may add value to clinical management.
- Published
- 2018
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