Chantelle Venter's research while affiliated with Stellenbosch University and other places

Publications (43)

Article
Full-text available
Background Post-acute sequelae of COVID-19 (PASC), also now known as long COVID, has become a major global health and economic burden. Previously, we provided evidence that there is a significant insoluble fibrin amyloid microclot load in the circulation of individuals with long COVID, and that these microclots entrap a substantial number of inflam...
Preprint
Full-text available
Earlier variants of SARS-CoV-2 have been associated with plasma hypercoagulability (as judged by thromboelastography) and an extensive formation of fibrin amyloid microclots, which are considered to contribute to the pathology of the coronavirus 2019 disease (COVID-19). The newer Omicron variants appear to be far more transmissible, but less virule...
Article
Full-text available
Background Fibrin(ogen) amyloid microclots and platelet hyperactivation previously reported as a novel finding in South African patients with the coronavirus 2019 disease (COVID-19) and Long COVID/Post-Acute Sequelae of COVID-19 (PASC), might form a suitable set of foci for the clinical treatment of the symptoms of Long COVID/PASC. A Long COVID/PAS...
Preprint
Full-text available
This is study of microclots in long-COVID patients, including treatment thereof, and a data-driven correlation of comorbidities with long-COVID symptoms. This is a corrected version. The preprint original is also at: https://doi.org/10.21203/rs.3.rs-1205453/v1
Preprint
Full-text available
We recognise that fibrin(ogen) amyloid microclots and platelet hyperactivation, that we have previously observed in COVID-19 and Long COVID/Post-Acute Sequelae of COVID-19 (PASC) patients, might form a suitable set of foci for the clinical treatment of the symptoms of long COVID/PASC. We first report on the comorbidities and symptoms found in a coh...
Preprint
Background : Fibrin(ogen) amyloid microclots and platelet hyperactivation previously reported as a novel finding in South African patients with the coronavirus 2019 disease (COVID-19) and Long COVID/Post-Acute Sequelae of COVID-19 (PASC), might form a suitable set of foci for the clinical treatment of the symptoms of long COVID/PASC. A Long COVID/P...
Article
Full-text available
An important component of severe COVID-19 disease is virus-induced endothelilitis. This leads to disruption of normal endothelial function, initiating a state of failing normal clotting physiology. Massively increased levels of von Willebrand Factor (VWF) lead to overwhelming platelet activation, as well as activation of the enzymatic (intrinsic) c...
Article
Full-text available
Background Severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2)-induced infection, the cause of coronavirus disease 2019 (COVID-19), is characterized by acute clinical pathologies, including various coagulopathies that may be accompanied by hypercoagulation and platelet hyperactivation. Recently, a new COVID-19 phenotype has been noted in p...
Article
Full-text available
Severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2) -induced infection, the cause of coronavirus disease 2019 (COVID-19), is characterized by unprecedented clinical pathologies. One of the most important pathologies, is hypercoagulation and microclots in the lungs of patients. Here we study the effect of isolated SARS-CoV-2 spike protein S...
Preprint
Full-text available
The coronavirus disease 2019 (COVID-19) (SARS-Cov-2) has caused a worldwide, sudden and substantial increase in hospitalizations for pneumonia with multiorgan problems. An important issue is also that there is still no unified standard for the diagnosis and treatment of COVID-19. Substantial vascular events are significant accompaniments to lung co...
Preprint
Full-text available
Background Severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2)-induced infection, the cause of coronavirus disease 2019 (COVID-19), is characterized by acute clinical pathologies, including various coagulopathies that may be accompanied by hypercoagulation and platelet hyperactivation. Recently, a new COVID-19 phenotype has been noted in p...
Article
Full-text available
Psoriasis is a chronic, immune-mediated inflammatory skin disease, affecting approximately 2% of the general population, which can be accompanied by psoriatic arthritis (PsA). The condition has been associated with an increased cardiovascular burden. Hypercoagulability is a potential underlying mechanism that may contribute to the increased risk of...
Preprint
Full-text available
Severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2)-induced infection, the cause of coronavirus disease 2019 (COVID-19), is characterized by acute clinical pathologies, including various coagulopathies that may be accompanied by hypercoagulation and platelet hyperactivation. Recently, a new COVID-19 phenotype has been noted in patients aft...
Preprint
Full-text available
Severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2) -induced infection, the cause of coronavirus disease 2019 (COVID-19), is characterized by unprecedented clinical pathologies. One of the most important pathologies, is hypercoagulation and microclots in the lungs of patients. Here we study the effect of isolated SARS-CoV-2 spike protein S...
Article
Breast cancer (BC) is one of the most prevalent forms of cancer in women worldwide. Clinical research indicates that BC patients are at an increased risk for thrombotic events, drastically decreasing their quality-of-life and treatment outcomes. There is ample evidence of this in the literature, but it is mainly focused on metastatic BC. Therefore,...
Article
The distribution of metals across the environment is increasingly becoming a major concern as they not only pollute the environment but also pose a danger to humans and animals. Human exposure to heavy metals often occurs as a combination of metals the synergistic effects of which can be more toxic than a single metal. The aim of this study was to...
Article
Full-text available
Aims The risk of cardiovascular events in patients with Rheumatoid Arthritis (RA) is disproportionately heightened as a result of systemic inflammation. The relative effect of autoimmune-associated citrullination on the structure and thrombotic potential of fibrin(ogen) remains unknown. We therefore compared indices of vascular function, inflammati...
Article
Full-text available
Background Type 2 Diabetes Mellitus (T2DM) is a well-known comorbidity to COVID-19 and coagulopathies are a common accompaniment to both T2DM and COVID-19. In addition, patients with COVID-19 are known to develop micro-clots within the lungs. The rapid detection of COVID-19 uses genotypic testing for the presence of SARS-Cov-2 virus in nasopharynge...
Article
Full-text available
Progressive respiratory failure is seen as a major cause of death in severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2)-induced infection. Relatively little is known about the associated morphologic and molecular changes in the circulation of these patients. In particular, platelet and erythrocyte pathology might result in severe vascular...
Preprint
Full-text available
Background: Type 2 Diabetes Mellitus (T2DM) is a well-known comorbidity to COVID-19 and coagulopathies are a common accompaniment to both T2DM and COVID-19. In addition, patients with COVID-19 are known to develop micro-clots within the lungs. The rapid detection of COVID-19 uses genotypic testing for the presence of SARS-Cov-2 virus in nasopharyng...
Preprint
Full-text available
Background Type 2 Diabetes Mellitus (T2DM) is a well-known comorbidity to COVID-19 and coagulopathies are a common accompaniment to both T2DM and COVID-19. In addition, patients with COVID-19 are known to develop micro-clots within the lungs. The rapid detection of COVID-19 uses genotypic testing for the presence of SARS-Cov-2 virus in nasopharynge...
Article
Full-text available
Materials and methods: The planktonic and biofilm-forming cultures were prepared in Middlebrook 7H9 and Sauton broth media, respectively, using Mtb strain, H37Rv. The effects of CSC at concentrations of 0.05-3.12 mg/L on growth, biofilm formation and structure were evaluated using microplate Alamar Blue assay, spectrophotometric procedure and scan...
Preprint
Full-text available
The rapid detection of COVID-19 uses genotypic testing for the presence of SARS-Cov-2 virus in nasopharyngeal swabs, but it can have a poor sensitivity. A rapid, host-based physiological test that indicated whether the individual was infected or not would be highly desirable. Coagulaopathies are a common accompaniment to COVID-19, especially micro-...
Article
Novel hyper-resistant bacteria were isolated from the Crven Dol mine (Allchar, North Macedonia), arsenic-rich extreme environment. Bacteria were recovered from a secondary mineral mixture, an alteration of hydrothermal realgar rich in arsenates (pharmacolite, hornesite, and talmessite). The sample was recovered from the dark part of the mine at 28...
Article
Full-text available
Background: Porphyromonas gingivalis and its inflammagens are associated with a number of systemic diseases, such as cardiovascular disease and type 2 diabetes (T2DM). The proteases, gingipains, have also recently been identified in the brains of Alzheimer's disease patients and in the blood of Parkinson's disease patients. Bacterial inflammagens,...
Preprint
Full-text available
Objective The risk of cardiovascular events in patients with RA is disproportionately heightened as a result of systemic inflammation. The relative effect of autoimmune-associated citrullination on the structure and thrombotic potential of fibrin(ogen) remains unknown. We therefore compared indices of vascular function, inflammation, coagulation an...
Article
The mining sector in South Africa is expected to be the fifth largest in the world. Both mining and transport are the most common reasons for an increased risk of human exposure to heavy metal contamination in South Africa. Due to increasing amounts of metals in the environment, this study identified three metals cadmium, chromium and mercury based...
Preprint
Full-text available
Background: Porphyromonas gingivalis and its inflammagens is associated with a number of systemic diseases, such as cardiovascular disease and type 2 diabetes (T2DM). The proteases, gingipains have also recently been identified in brains of Alzheimer’s disease patients and in blood of Parkinson’s disease patients. Bacterial inflammagens, including...
Article
Increased anthropogenic activity and subsequent environmental exposure to heavy metals induce the production of reactive oxygen species (ROS), which increases oxidative stress and the risk of associated diseases. The aim of this study, in a subacute model of toxicity, was to investigate the effects of copper (Cu), manganese (Mn), and mercury (Hg) a...
Article
Bacterium Acinetobacter baumannii is a leading cause of hospital infections. Over the last decade, its occurrence in natural environments outside hospital settings has been reported. The aim was to examine the survival of A. baumannii in water media exposed to different range of oxygen supply in order to predict its behaviour in the environment. Th...
Article
The appearance and spread of antibiotic resistance are considered a highly complex process with many factors affecting the resistance mechanisms, including metals. In order to fully understand the spread of antibiotic resistance in different environments, combined studies including geochemistry and microbiology are becoming imperative. So far, very...
Article
The extensively- and pandrug-resistant isolates of Acinetobacter baumannii are a leading cause of hospital ac- quired infections. Aside from reports of A. baumannii in wastewaters influenced by hospital effluents, only two studies reported its detection in soils. The lack of data hinders the assessment of soil as the possible environ- mental reserv...
Article
Full-text available
Environmental presence and human exposure to heavy metals in air and cigarette smoke has led to a worldwide increase in respiratory disease. The effects of oral exposure to heavy metals in liver and kidney structure and function have been widely investigated and the respiratory system as a target is often overlooked. The aim of the study was to inv...
Article
Environmental presence and human exposure to heavy metals in air and cigarette smoke has led to a worldwide increase in respiratory disease. The effects of oral exposure to heavy metals in liver and kidney structure and function have been widely investigated and the respiratory system as a target is often overlooked. The aim of the study was to inv...
Article
Water contamination with metals due to anthropogenic activity is increasing and subsequent exposure increases the risk of associated toxicity. Exposure is not limited to a single metal but usually involves mixtures of different metals at different concentrations. Little is known about the contribution of this type of exposure, in humans, to the dev...
Article
Full-text available
Background/aims: Heavy metal pollution is increasing in the environment, contaminating water, food and air supplies. This can be linked to many anthropogenic activities. Heavy metals are absorbed through the skin, inhalation and/or orally. Irrespective of the manner of heavy metal entry in the body, the blood circulatory system is potentially the...
Article
On the cover: The cover image, by Chantelle Venter et al., is based on the Research Article Effects of metals cadmium and chromium alone and in combination on the liver and kidney tissue of male Spraque-Dawley rats: An ultrastructural and electron-energy-loss spectroscopy investigation, DOI 10.1002/jemt.22877.
Article
Full-text available
Water contamination with heavy metals may adversely affect our health. High metal levels lead to changes in blood coagulation processes, increasing the risk for cardiovascular disease. Exposure is not limited to a single metal but usually involves a mixture of metals. In this study 24 male Sprague-Dawley rats were exposed to cadmium (Cd) and mercur...
Article
Heavy metal pollution has increased in the last decades. Water sources are contaminated and human exposure is often long term exposure to variable amounts of different metals. In this study, male Sprague-Dawley rats were exposed via oral gavage for 28 days to cadmium (Cd) and chromium (Cr), alone and in combination at concentrations 1000 times the...
Article
Excessive agriculture, transport and mining often lead to the contamination of valuable water resources. Communities using this water for drinking, washing, bathing and the irrigation of crops are continuously being exposed to these heavy metals. The most vulnerable is the developing fetus. Cadmium (Cd) and chrome (Cr) were identified as two of the...
Article
Fixation of biological samples is an important process especially related to histological and ultrastructural studies. Chemical fixation was the primary method of fixing tissue for transmission electron microscopy for many years, as it provides adequate preservation of the morphology of cells and organelles. High pressure freezing (HPF) and freeze...

Citations

... The demographics, serum ferritin and IL-6 levels performed on the day of blood collection, self-reported symptom analysis and comorbidities before suffering from acute COVID-19 of our long COVID patients and controls are shown in Table 1 below. Our results follow trends reported on previously [34,35]. Interestingly, previously it has beenreported that misfolded protein aggregates behave as infectious agents [36]. ...
... To date, no drug has been shown to be of proven value in the treatment of PACS, although many substances are proposed as symptomatic treatments [75,92,[104][105][106][107][108]. Considering the known coagulation disorder in COVID-19 [109] and the low vascular perfusion seen in PACS, one could propose administering with due caution aspirin at a low dose to limit the risk of micro-thrombi at the level of the damaged vessels as is done in COVID-19 in high doses [110,111]. ...
... They used this term as an atypical acute respiratory distress syndrome because of lung damage, primarily explained by dramatic alveolar endothelial damage leading to a progressive endothelial pulmonary syndrome with microvascular thrombosis [9]. In the acute phase of COVID-19, patients present with multi-organ symptoms [10] and this phase is characterized by acute clinical pathologies, including various coagulopathies that may be accompanied by hypercoagulation and platelet hyperactivation [11][12][13][14][15][16][17]. If these coagulopathies are not adequately treated during the acute phase of the disease, possible tissue hypoxia and impaired oxygen exchange may linger for months. ...
... Post-acute sequelae of COVID-19 (PASC), now commonly referred to as long COVID, has quickly become a major global health and economic burden [1][2][3][4]. SARS-CoV-2 typically makes use of the cell surface receptor angiotensin-converting enzyme 2 (ACE2), to enter target cells. ACE2 receptors are expressed on the surface of lung epithelial cells, enterocytes of the small intestine and are also present in arterial and venous endothelial cells as well as arterial smooth muscle cells of multiple organs [5]. ...
... [76]. Hypercoagulation, vascular complications [77] and microclots formation in COVID-19 have already been identified [78]. PACS is accompanied by increased levels of antiplasmin [79], and pericytes-the multipotent parietal cells of capillaries-may play an important role in microvascular PACS alterations [80]. ...
... Regarding platelet activation, numerous secretory mediators are released, and different kinds of adhesive and immune receptors are expressed on their membranes, leading to the initiation and modulation of inflammatory and immune responses [1]; nevertheless, they are able to synthesize the growth factors up to over 7 days after activation from accumulated mRNA [7]. The mean platelet volume (MPV), which is used as a marker of platelet activation [8,9], is increased during psoriasis, confirming the presence of larger, more reactive platelets resulting from heightened platelet 2 of 8 turnover [10]. However, the exact mechanisms of these associations, especially before the onset of the pathology, remain unclear. ...
... These events must also be seen in the context of endothelial injury or altered fibrinolysis otherwise [14][15][16]. Persistence of an anomalous clotting profile in other regards has also been proposed well after acute infections [17]. ...
... Неврологические нарушения при этой патологии очевидно возникают как в результате прямого цитотоксического действия вируса, так и митохондриальной дисфункции и тромботических нарушений [4]. Тем не менее, у выживших больных основные нарушения центральной нервной системы очевидно будут связаны с последствиями тромбоза мелких сосудов коры головного и мозга и амилоидозом головного мозга и периферической нервной системы, поскольку быстрое образование амилоида, как оказалось, является первичной причиной тромбообразования при COVID-19 [9]. ...
... They are major stimuli for hematological perturbations. This is the rationale behind the frequent application of hematological indices as a toxicological bio-indicator for assessing or monitoring the in vivo effect of toxicants (Ran et al. 2015;Maseko et al. 2021). The erythrocyte membrane, composing of the glycocalyx and lipid bilayer, particularly remains a reference point in hematological considerations due to its sensitivity and diaphaneity. ...
... Hypercoagulation can be caused by any number of traumas or shocks to the system, from the more obviously acute kind of trauma [322][323][324], to the presence of molecules such as free iron [325][326][327][328][329][330], bacterial LPS [267,268,[331][332][333], and lipoteichoic acid [268], or, most pertinently, the S1 spike protein of SARS-CoV-2 [84]. Coagulopathies are also a feature of rheumatoid arthritis [14,[334][335][336][337] and indeed all kinds of inflammatory diseases [326,[338][339][340][341][342][343][344][345], including of course COVID-19 [346][347][348][349] and ME/ CFS [350][351][352]. However, although these links are well established, there is an important twist that makes the kind of coagulation we are talking about anomalous because it leads to fibrin amyloid-containing clots that are more resistant than usual to fibrinolysis. ...