Elevated levels of cell-free circulating DNA in patients with acute dengue virus infection

Portable Point-of-Care Diagnosis Platforms and Emerging Predictive Biomarkers for Rapid Detection of Severe Dengue Viral Infection

Dengue virus (DENV) infection is a major global public health problem, particularly in tropical and subtropical regions where Aedes mosquitoes are prevalent. The clinical spectrum of dengue ranges from mild febrile illness to severe conditions such as dengue hemorrhagic fever and dengue shock syndrome. Early prediction of dengue progress is crucial for timely therapeutic medications, which can reduce both morbidity and mortality. Traditional diagnostic methods such as serological tests and polymerase chain reactions are often time-consuming and require sophisticated infrastructure and skilled personnel. To overcome these limitations, the development of point-of-care (POC) diagnosis platforms and novel predictive biomarkers is crucial to providing rapid, real-time diagnostic tools that can be used in low-resource settings and at the patient's bedside. Predictive biomarkers enable the identification of disease risk in the early stages and can reduce hospitalization visits. This review offers a comprehensive overview of portable POC diagnosis platforms and emerging predictive biomarkers for the rapid diagnosis of severe DENV infection. Its provides an overview of its epidemiology, discusses the global burden of DENV, and explores DENV infection with different serotypes, as well as the clinical spectrum and severity of dengue. The key focus is on the latest advancements in POC diagnosis readout methods and portable POC devices for DENV diagnosis, including colorimetric assay, electrochemical method, lateral flow strip, and microfluidic chip platforms. In addition, the review article explores various emerging predictive biomarkers for the rapid detection of DENV, while also highlighting the limitations associated with protein, nucleic acid, and metabolic biomarkers. Finally, we address the current challenges, limitations, and potential future directions of POC diagnosis platforms for the diagnosis of severe DENV infection.

Biocompatible PVA/gelatin and PVA/starch nanofibers incorporating sodium lactobionate obtained from enzymatic synthesis

This study reports the first incorporation of sodium lactobionate (SL), bioproduced via enzymatic synthesis using Zymomonas mobilis, into electrospun nanofibers. SL was combined with poly(vinyl alcohol) (PVA) and either gelatin or starch to form the nanofibers, which exhibited uniform structures with diameters ranging from 297.4 to 367.5 nm. The physical, thermal, and mechanical properties of the nanofibers were influenced by the presence of SL, gelatin, or starch. The formulation with gelatin and SL demonstrated the most significant antioxidant activity, achieving 62.59 % (1360.88 μM TEAC) in the ABTS assay. The nanofibers showed low hemolysis rate (0.08 % to 3.18 %) and were classified as biocompatible. No significant effects on cell viability, ROS production, NO levels, or dsDNA release were observed up to 1000 μg/mL over 24 h, indicating their safety profile. PVA/gelatin/SL nanofibers show promising potential as carriers for bioactive compounds in pharmaceutical, food, chemical, and nanotechnology applications.

Mitochondrial DNA signals driving immune responses: Why, How, Where?

There has been a recent expansion in our understanding of DNA-sensing mechanisms. Mitochondrial dysfunction, oxidative and proteostatic stresses, instability and impaired disposal of nucleoids cause the release of mitochondrial DNA (mtDNA) from the mitochondria in several human diseases, as well as in cell culture and animal models. Mitochondrial DNA mislocalized to the cytosol and/or the extracellular compartments can trigger innate immune and inflammation responses by binding DNA-sensing receptors (DSRs). Here, we define the features that make mtDNA highly immunogenic and the mechanisms of its release from the mitochondria into the cytosol and the extracellular compartments. We describe the major DSRs that bind mtDNA such as cyclic guanosine-monophosphate-adenosine-monophosphate synthase (cGAS), Z-DNA-binding protein 1 (ZBP1), NOD-, LRR-, and PYD- domain-containing protein 3 receptor (NLRP3), absent in melanoma 2 (AIM2) and toll-like receptor 9 (TLR9), and their downstream signaling cascades. We summarize the key findings, novelties, and gaps of mislocalized mtDNA as a driving signal of immune responses in vascular, metabolic, kidney, lung, and neurodegenerative diseases, as well as viral and bacterial infections. Finally, we define common strategies to induce or inhibit mtDNA release and propose challenges to advance the field.

Could the inhibition of systemic NLRP3 inflammasome mediate central redox effects of yerba mate? An in silico and pre-clinical translational approach

ETHNOPHARMACOLOGICAL RELEVANCE

Empirically, Ilex paraguariensis A. St. Hil, or yerba-mate, has been used by natives of South America as a stimulant. Nowadays, this plant has gained popularity due to its neuroprotective effects. However, there are few studies on the biochemical-molecular mechanisms of action involved in its effect.

AIM OF THE STUDY

Chemically characterize an aqueous extract of yerba mate (YME) and evaluate if it could suppress the aberrant inflammatory response related to neurodegeneration.

MATERIALS AND METHODS

Macrophages and microglia cells were exposed to lipopolysaccharide (LPS; 100 ng/mL) plus nigericin (100 μM) or quinolinic acid (QA; 5 mM). Cellular viability, oxidative, and inflammatory markers were evaluated. Chemical matrix (HPLC - DAD), antioxidant activity, safety profile in vitro and in vivo, and an in silico docking of main targets were also assessed.

RESULTS

Pre-treatment with YME (15 μg/mL) prevented impairments in redox metabolism and inflammatory markers in BV-2 cells. In macrophages, YME showed similar results to MCC950, an inflammasome inhibitor. YME presented 282.88 mg EAG/g total phenolic content and a redox capacity of 32.94 ± 1.30 μg/mL (IC50), and its major compounds were chlorogenic acid > rutin > ferulic acid > catechin > sinapic acid. Chlorogenic acid and rutin presented a high affinity to the MCC950 region. Additionally, YME did not cause genotoxicity and was safe in vivo.

CONCLUSION

YME has significantly affected macrophages and microglia by regulating the NLRP3 inflammatory pathway.

Increased Presence of Circulating Cell-Free, Fragmented, Host DNA in Pigs Infected with Virulent African Swine Fever Virus

African swine fever virus (ASFV) causes severe hemorrhagic disease in domestic pigs and wild boar, often with high case fatality rates. The virus replicates in the circulating cells of the monocyte-macrophage lineage and within lymphoid tissues. The infection leads to high fever and a variety of clinical signs. In this study, it was observed that ASFV infection in pigs resulted in a >1000-fold increase in the level of circulating cell-free DNA (cfDNA), derived from the nuclei of host cells in the serum. This change occurred in parallel with the increase in circulating ASFV DNA. In addition, elevated levels (about 30-fold higher) of host mitochondrial DNA (mtDNA) were detected in the serum from ASFV-infected pigs. For comparison, the release of the cellular enzyme, lactate dehydrogenase (LDH), a commonly used marker of cellular damage, was also found to be elevated during ASFV infection, but later and less consistently. The sera from pigs infected with classical swine fever virus (CSFV), which causes a clinically similar disease to ASFV, were also tested but, surprisingly, this infection did not result in the release of cfDNA, mtDNA, or LDH. It was concluded that the level of cfDNA in the serum is a sensitive host marker of virulent ASFV infection.

Evidence for the utility of cfDNA plasma concentrations to predict disease severity in COVID-19: a retrospective pilot study

Background

COVID-19 is a worldwide pandemic caused by the highly infective SARS-CoV-2. There is a need for biomarkers not only for overall prognosis but also for predicting the response to treatments and thus for improvements in the clinical management of patients with COVID-19. Circulating cell-free DNA (cfDNA) has emerged as a promising biomarker in the assessment of various pathological conditions. The aim of this retrospective and observational pilot study was to investigate the range of cfDNA plasma concentrations in hospitalized COVID-19 patients during the first wave of SARS-CoV-2 infection, to relate them to established inflammatory parameters as a correlative biomarker for disease severity, and to compare them with plasma levels in a healthy control group.

Methods

Lithium-Heparin plasma samples were obtained from COVID-19 patients (n = 21) during hospitalization in the University Medical Centre of Mainz, Germany between March and June 2020, and the cfDNA concentrations were determined by quantitative PCR yielding amplicons of long interspersed nuclear elements (LINE-1). The cfDNA levels were compared with those of an uninfected control group (n = 19).

Results

Plasma cfDNA levels in COVID-19 patients ranged from 247.5 to 6,346.25 ng/ml and the mean concentration was 1,831 ± 1,388 ng/ml (± standard deviation), which was significantly different from the levels of the uninfected control group (p < 0.001). Regarding clinical complications, the highest correlation was found between cfDNA levels and the myositis (p = 0.049). In addition, cfDNA levels correlated with the "WHO clinical progression scale". D-Dimer and C-reactive protein (CRP) were the clinical laboratory parameters with the highest correlations with cfDNA levels.

Conclusion

The results of this observational pilot study show a wide range in cfDNA plasma concentrations in patients with COVID-19 during the first wave of infection and confirm that cfDNA plasma concentrations serve as a predictive biomarker of disease severity in COVID-19.

The Diagnostic, Prognostic, and Therapeutic Potential of Cell-Free DNA with a Special Focus on COVID-19 and Other Viral Infections

Cell-free DNA (cfDNA) in human blood serum, urine, and other body fluids recently became a commonly used diagnostic marker associated with various pathologies. This is because cfDNA enables a much higher sensitivity than standard biochemical parameters. The presence of and/or increased level of cfDNA has been reported for various diseases, including viral infections, including COVID-19. Here, we review cfDNA in general, how it has been identified, where it can derive from, its molecular features, and mechanisms of release and clearance. General suitability of cfDNA for diagnostic questions, possible shortcomings and future directions are discussed, with a special focus on coronavirus infection.

Senotherapeutics: An emerging approach to the treatment of viral infectious diseases in the elderly

In the context of the global COVID-19 pandemic, the phenomenon that the elderly have higher morbidity and mortality is of great concern. Existing evidence suggests that senescence and viral infection interact with each other. Viral infection can lead to the aggravation of senescence through multiple pathways, while virus-induced senescence combined with existing senescence in the elderly aggravates the severity of viral infections and promotes excessive age-related inflammation and multiple organ damage or dysfunction, ultimately resulting in higher mortality. The underlying mechanisms may involve mitochondrial dysfunction, abnormal activation of the cGAS-STING pathway and NLRP3 inflammasome, the role of pre-activated macrophages and over-recruited immune cells, and accumulation of immune cells with trained immunity. Thus, senescence-targeted drugs were shown to have positive effects on the treatment of viral infectious diseases in the elderly, which has received great attention and extensive research. Therefore, this review focused on the relationship between senescence and viral infection, as well as the significance of senotherapeutics for the treatment of viral infectious diseases.

Eucalyptus oil nanoemulsions against eggs and larvae of Haemonchus contortus

Haemonchus contortus is a highly pathogenic and prevalent helminth that causes many deaths in sheep herds. Anthelmintics are usually employed to overcome this issue; however, they do not guarantee immediate and lasting efficacy because of the occurrence of drug-resistant parasites. Among substances that are used in scientific studies for parasitic control, essential oils are known to have different pharmacological properties. However, they demonstrate instability owing to several factors, and therefore, nanoemulsification is considered an alternative to control the instability and degradability of these compounds. The objective of this study was to evaluate the cytotoxicity of nanoemulsions containing essential oil of Eucalyptus globulus against the blood of healthy sheep and to verify their activity against the parasite H. contortus in sheep. The results presented adequate nanotechnological characteristics (diameter 72 nm, PDI 0.2, zeta -11 mV, and acidic pH) and adequate morphology. Further, the corona effect and cytotoxic profiles of the free oil and nanoemulsion against blood cells from healthy sheep were evaluated. The tests results did not present a toxicity profile. For evaluating efficacy, we observed an important anthelmintic action of the nanoemulsion containing oil in comparison to the free oil; the results demonstrate a potential role of the nanoemulsion in the inhibition of egg hatchability and the development of larvae L1 to L3 (infective stage). Based on these results, we developed an important and potential anthelmintic alternative for the control of the parasite H. contortus.

Richardia brasiliensis Gomes: phytochemical characterization, antiproliferative capacity and in vitro and in vivo toxicity

Richardia brasiliensis, known as poaia branca, is a medicinal species widely distributed throughout Brazil and used in folk medicine. However, studies on its toxicity are practically non-existent, and little is known about its biological activity. This study aimed to investigate its phytochemical compounds, assess its in vitro and in vivo toxicities, and determine its antiproliferative activity. UHPLC-ESI-HRFTMS performed the phytochemical characterization, and the antiproliferative activity was analyzed in different tumor cell lines. In vitro toxicity was evaluated in PBMC cells, and in vivo acute and repeated dose toxicity was evaluated according to OECD guidelines. It was identified alkaloids and terpenes as significant compounds. Regarding its antiproliferative activity, the human melanoma strain decreased its viability by about 95%. In vitro toxicity showed that the extracts maintained the viability of PBMCs; however, higher concentrations were able to increase the production of dsDNA quantity. In vivo tests showed no mortality nor signs of toxicity; the alterations found in hematological and biochemical parameters are within the standards for the species. The results indicate that R. brasiliensis has a good effect against the tumor cell line; still, more studies on its toxicity at higher concentrations are needed.

Chlorpyrifos pesticide promotes oxidative stress and increases inflammatory states in BV-2 microglial cells: A role in neuroinflammation

The exposure to environmental stressors, such as organophosphate (OP) pesticides, has been associated with the development of neurodegenerative diseases. Chlorpyrifos (CPF) is the worldwide most used OP pesticide and one of the most hazardous pesticides as it can cross the blood-brain barrier. Since studies evaluating the effects of CPF on brain immune cells are scarce, this research investigated the oxidative and inflammatory responses of CPF exposure in murine microglial cells. BV-2 cells were exposed to different concentrations of CPF pesticide (0.3-300 μM). CPF induced activation of microglial cells, confirmed by Iba-1 and CD11b marking, and promoted microglial proliferation and cell cycle arrest at S phase. Moreover, CPF exposure increased oxidative stress production (NO, MDA, and O₂∙), and upregulated pro-inflammatory cytokines (IL-1β and NLRP3) genes expression in BV-2 cells. Overall, data showed that CPF exposure, at the lowest concentrations, acted by promoting pro-oxidative and pro-inflammatory states in microglial cells. These results provide important information on the potential role of microglial activation in CPF-induced neuroinflammation and add to the expanding knowledge on the neurotoxicity of OP.

In Vitro Evaluation of Antioxidant and Anticancer Activity of Lemongrass (Cymbopogon citratus (D.C.) Stapf)

Cancer is considered a multifactorial disease and its development could be associated with several factors, for example, rotenone exposition. Unfortunately, many cancers are resistant to chemotherapy, as cervical cancer. Regarding this, lemongrass is a remarkable natural product that presents antioxidant and anticancer activities, which could show therapeutic action against rotenone and cervical cancer. Thus, this study aimed to investigate the antioxidant and anticancer action of lemongrass. An in vitro study was conducted using VERO (kidney cells) and SiHa cell lines (cervical cancer cells). VERO cells were exposed to rotenone and lemongrass extract for 24 and 72 h. While SiHa cells were exposed to lemongrass isolated and associated to chemotherapy, 5-fluorouracil, during 24 and 48 h. After, levels of viability, proliferation, and oxidative metabolism were determined. The results showed that lemongrass presents antioxidant activity on VERO cells by increasing cell viability and proliferation and decreasing oxidative stress caused by rotenone. Moreover, lemongrass showed anticancer activity by decreasing cell viability and increasing oxidative stress parameters on SiHa. Besides, lemongrass had no alteration in the chemotherapy activity. Therefore, this study revealed that lemongrass presents antioxidant and anticancer activity since it can protect against the cytotoxicity of rotenone and reduce the cell viability of cervical cancer.

Neutrophils at the crossroads of acute viral infections and severity

Neutrophils are versatile immune effector cells essential for mounting a first-line defense against invading pathogens. However, uncontrolled activation can lead to severe life-threatening complications. Neutrophils exist as a heterogeneous population, and their interaction with pathogens and other immune cells may shape the outcome of the host immune response. Diverse classes of viruses, including the recently identified novel SARS-CoV-2, have shown to alter the various aspects of neutrophil biology, offering possibilities for selective intervention. Here, we review heterogeneity within the neutrophil population, highlighting the functional consequences of circulating phenotypes and their critical involvement in exaggerating protective and pathological immune responses against the viruses. We discuss the recent findings of neutrophil extracellular traps (NETs) in COVID-19 pathology and cover other viruses, where neutrophil biology and NETs are crucial for developing disease severity. In the end, we have also pointed out the areas where neutrophil-mediated responses can be finely tuned to outline opportunities for therapeutic manipulation in controlling inflammation against viral infection.

Parasporin A13-2 of Bacillus thuringiensis Isolates from the Papaloapan Region (Mexico) Induce a Cytotoxic Effect by Late Apoptosis against Breast Cancer Cells

The protein A13-2 was obtained from Bacillus thuringiensis strains isolated from the Papaloapan watershed region (Oaxaca, Mexico). The cytotoxic activity of parasporal inclusions was studied against breast cancer cell line (MCF-7) and normal cell (human peripheral blood mononuclear cells). The MTT, the formation of reactive species, nitric oxide, free cell DNA, and the type of death cellular were assessed. The protein A13-2 shows the highest cytotoxic activity against MCF-7 (13% cell viability at 6 µg/mL), the extracellular DNA increases, and it shows no stress for reactive species or nitric oxide. Besides, the A13-2 parasporin shows no toxicity to peripheral blood mononuclear cells, and it does not generate changes in nitric oxide levels or free cell DNA. Due to that, the cytotoxic effect of A13-2 was specific for MCF-7, and it does not affect normal cells. According to microscopy and flow cytometry, A13-2 parasporin leads to the death of MCF-7 cells by late apoptosis together with necrosis and without allowing the triggering of the survival mechanisms. When analyzed together, our results show for the first time that the A13-2 protein isolated from Mexican strains of B. thuringiensis preferentially kills MCF- 7 (cancer cells) over HEK 293 and PBMC cell lines (normal cells), thus representing a promising alternative for the treatment of cancer breast.

Circulating Biomarkers for Early Stage Non-Small Cell Lung Carcinoma Detection: Supplementation to Low-Dose Computed Tomography

Lung cancer is currently the leading cause of cancer death in both developing and developed countries. Given that lung cancer has poor prognosis in later stages, it is essential to achieve an early diagnosis to maximize patients’ overall survival. Non-small cell lung cancer (NSCLC) is the most common form of primary lung cancer in both smokers and non-smokers. The current standard screening method, low‐dose computed tomography (LDCT), is the only radiological method that demonstrates to have mortality benefits across multiple large randomized clinical trials (RCT). However, these RCTs also found LDCT to have a significant false positive rate that results in unnecessary invasive biopsies being performed. Due to the lack of both sensitive and specific screening methods for the early detection of lung cancer, there is an urgent need for alternative minimally or non-invasive biomarkers that may provide diagnostic, and/or prognostic information. This has led to the identification of circulating biomarkers that can be readily detectable in blood and have been extensively studied as prognosis markers. Circulating microRNA (miRNA) in particular has been investigated for these purposes as an augmentation to LDCT, or as direct diagnosis of lung cancer. There is, however, a lack of consensus across the studies on which miRNAs are the most clinically useful. Besides miRNA, other potential circulating biomarkers include circulating tumor cells (CTCs), circulating tumor DNA (ctDNAs) and non-coding RNAs (ncRNAs). In this review, we provide the current outlook of several of these biomarkers for the early diagnosis of NSCLC.

Tucumã (Astrocaryum aculeatum) Prevents Oxidative and DNA Damage to Retinal Pigment Epithelium Cells

Eye diseases have a negative impact on the eyesight quality of the world population. The age-related macular degeneration (AMD) draws special attention since it is a chronic disorder characterized by oxidative and inflammatory damage to the retinal epithelial pigment, which triggers progressive vision loss. In the Brazilian Amazon, Astrocaryum aculeatum is an Amazonian fruit (Tucumã) used by riverside communities in traditional medicine to treat a number of ailments. These communities have recently shown to have increased longevity and reduced prevalence of age-related morbidity. Thus, the aim of this research was to chemically characterize and analyze the in vitro antioxidant effect and molecular damage prevention of the Tucumã ethanolic extract in retinal pigment epithelium (RPE) cells in a model for AMD. The extract was chemically characterized by ultra-high-performance liquid chromatography (HPLC) coupled with diode-array detection and mass spectrophotometry (HPLC-DAD-MS). In vitro protocols were performed, and the cytopreventive effect of Tucumã on RPE cells exposed to high concentrations of superoxide anion, an oxidant and genotoxic molecule, as well as the effect of Tucumã extract on oxidative and molecular makers were assessed. Biochemical and flow cytometry analyses were conducted in these protocols. The extract presents high concentrations of caffeic acid, gallic acid, catechin, luteolin, quercetin, and rutin. Treatment did not show cytotoxic effects in cells treated only with extract at 50 μg/mL. In fact, it improved cell viability and was able to prevent necrosis and apoptosis, and oxidative and molecular damage was significantly reduced. In summary, Tucumã is an important Amazon fruit, which seems to contribute significantly to improve human health conditions, as our findings suggest that its extract has a relevant chemical matrix rich in antioxidant molecules, and its consumption could improve eye health and contribute to prevention against oxidative stress through cytoprevention, reactive oxygen species reduction, and maintenance of DNA integrity in retinal pigment epithelium (RPE) cells.

MnSOD Ala16Val polymorphism in cognitive dysfunction in patients with epilepsy: A relationship with oxidative and inflammatory markers

OBJECTIVE

The objective of the study was to evaluate the neurocognitive profile and its relation with Ala16ValMnSOD polymorphism in epilepsy and if these clinical parameters are linked to oxidative stress and inflammatory markers.

METHODS

Patients with epilepsy (n = 31) and healthy subjects (n = 42) were recruited. A neuropsychological evaluation was performed in both groups through a battery of cognitive tests. Oxidative stress, inflammatory markers, apoptotic factors, and deoxyribonucleic acid (DNA) damage were measured in blood samples.

RESULTS

Statistical analyses showed the association of MnSOD Ala16Val polymorphism with cognitive impairment, including praxis, perception, attention, language, executive functions, long-term semantic memory, short-term visual memory, and total memory in patients with epilepsy and Valine-Valine (VV) genotype compared with the control group. Compared with the controls and patients with epilepsy, Alanine-Alanine (AA), and Alanine-Valine (AV) genotype, the patients with epilepsy and VV genotype exhibited higher levels of tumor necrosis factor alpha (TNF-α), interleukin 1β (IL-1β), interleukin 6 (IL-6), activation of caspases 1 and 3 (CASP-1 and -3), and DNA damage. Our findings also showed higher carbonyl protein and thiobarbituric acid reactive substances (TBARS) levels as well as an increased superoxide dismutase (SOD) and acetylcholinesterase (AChE) activities in patients with epilepsy and VV genotype.

CONCLUSION

This study supports the evidence of a distinct neuropsychological profile in patients with epilepsy, especially those with the VV genotype. Furthermore, our results suggest that oxidative and inflammatory pathways may be associated with genetic polymorphism and cognitive dysfunction in patients with epilepsy.

Kinetics of CD4+ T Helper and CD8+ Effector T Cell Responses in Acute Dengue Patients

Background: The protective or pathogenic role of T lymphocytes during the acute phase of dengue virus (DENV) infection has not been fully understood despite its importance in immunity and vaccine development.

Objectives: This study aimed to clarify the kinetics of T lymphocyte subsets during the clinical course of acute dengue patients.

Study design: In this hospital-based cohort study, 59 eligible Vietnamese dengue patients were recruited and admitted. They were investigated and monitored for T cell subsets and a panel of clinical and laboratory parameters every day until discharged and at post-discharge from the hospital.

Results: We described for the first time the kinetics of T cell response during the clinical course of DENV infection. Severe cases showed significantly lower levels of effector CD8⁺ T cells compared to mild cases at day −1 (p = 0.017) and day 0 (p = 0.033) of defervescence. After defervescence, these cell counts in severe cases increased rapidly to equalize with the levels of mild cases. Our results also showed a decline in total CD4⁺ T, Th1, Th1/17 cells during febrile phase of dengue patients compared to normal controls or convalescent phase. On the other hand, Th2 cells increased during DENV infection until convalescent phase. Cytokines such as interferon-γ, IL-12p70, IL-5, IL-23, IL-17A showed tendency to decrease on day 0 and 1 compared with convalescence and only IL-5 showed significance indicating the production during acute phase was not systemic.

Conclusion: With a rigorous study design, we uncovered the kinetics of T cells in natural DENV infection. Decreased number of effector CD8⁺ T cells in the early phase of infection and subsequent increment after defervescence day probably associated with the T cell migration in DENV infection.

Cell-Free Circulating Mitochondrial DNA: A Potential Blood-Based Marker for Atrial Fibrillation

Atrial fibrillation (AF), the most common, progressive tachyarrhythmia is associated with serious complications, such as stroke and heart failure. Early recognition of AF, essential to prevent disease progression and therapy failure, is hampered by the lack of accurate diagnostic serum biomarkers to identify the AF stage. As we previously showed mitochondrial dysfunction to drive experimental and human AF, we evaluated whether cell-free circulating mitochondrial DNA (cfc-mtDNA) represents a potential serum marker. Therefore, the levels of two mtDNA genes, COX3 and ND1, were measured in 84 control patients (C), 59 patients undergoing cardiac surgery without a history of AF (SR), 100 paroxysmal (PAF), 116 persistent (PeAF), and 20 longstanding-persistent (LS-PeAF) AF patients undergoing either cardiac surgery or AF treatment (electrical cardioversion or pulmonary vein isolation). Cfc-mtDNA levels were significantly increased in PAF patients undergoing AF treatment, especially in males and patients with AF recurrence after AF treatment. In PeAF and LS-PeAF, cfc-mtDNA levels gradually decreased. Importantly, cfc-mtDNA in serum may originate from cardiomyocytes, as in vitro tachypaced cardiomyocytes release mtDNA in the medium. The findings suggest that cfc-mtDNA is associated with AF stage, especially in males, and with patients at risk for AF recurrence after treatment.

Current Advances and Future Perspectives of Cerebrospinal Fluid Biopsy in Midline Brain Malignancies

OPINION STATEMENT

Malignancies arising in midline brain structures, including lymphomas, teratomas, germinomas, diffuse midline gliomas, and medulloblastomas typically respond to systemic therapies, and excessive surgical excision can result in serious complications, so that total surgical removal is not routinely performed. Identifying tumor specific biomarkers that can facilitate diagnosis at early stage and allow for dynamic surveillance of the tumor is of great clinical importance. However, existing standard methods for biopsy of these brain neoplasms are high risk, time consuming, and costly. Thus, less invasive and more rapid diagnosis tests are urgently needed to detect midline brain malignancies. Currently, tools for cerebrospinal biopsy of midline brain malignancies mainly include circulating tumor DNA, circulating tumor cells, and extracellular vesicles. Circulating tumor DNA achieved minimally invasive biopsy in several brain malignancies and has advantages in detecting tumor-specific mutations. In the field of tumor heterogeneity, circulating tumor cells better reflect the genome of tumors than surgical biopsy specimens. They can be applied for the diagnosis of leptomeningeal metastasis. Extracellular vesicles contain lots of genetic information about cancer cells, so they have potential in finding therapeutic targets and studying tumor invasion and metastasis.

Immunomodulatory effect of mancozeb, chlorothalonil, and thiophanate methyl pesticides on macrophage cells

Mancozeb (MZ), chlorothalonil (CT), and thiophanate methyl (TM) are pesticides commonly used in agriculture due to their efficacy, low acute toxicity to mammals, and short environmental persistence. Although the toxic effects of these pesticides have been previously reported, studies regarding their influence on the immune system are limited. As such, this study focused on the immunomodulatory effect of MZ, CT, and TM pesticides on macrophage cells. RAW 264.7 cells were exposed to a range of concentrations (0.1-100 μg/mL) of these pesticides. CT exposure promoted an increase in reactive oxygen species (ROS) and nitric oxide (NO) levels. The MTT and ds-DNA assay results demonstrated that MZ, CT, and TM exposure induced macrophage proliferation. Moreover, MZ, CT, and TM promoted cell cycle arrest at S phase, strongly suggesting macrophage proliferation. The levels of pro-inflammatory cytokines (IL-1β, IL-6, TNF-α, and IFN-γ) and caspases (caspase 1, 3, and 8) in macrophages exposed to MZ, CT, and TM pesticides increased, whereas the anti-inflammatory cytokine levels decreased. These results suggest that MZ, CT, and TM exert an immunomodulatory effect on the immune system, inducing macrophage activation and enhancing the inflammatory response.

Comprehensive Evaluation of the Factors Affecting Plasma Circulating Cell-Free DNA Levels and Their Application in Diagnosing Nonsmall Cell Lung Cancer

AIMS

Circulating cell-free DNA (ccfDNA) is a valuable biomarker, but the ccfDNA levels are influenced by variations that occur during sample processing. The feasibility of using ccfDNA as a diagnostic biomarker requires further examination.

MATERIALS AND METHODS

We established a real-time PCR assay with an external standard to comprehensively evaluate the factors affecting ccfDNA levels, including the extraction kit used, freeze-thaw stability, and stability of delayed extraction. Then we compared the ccfDNA levels between benign controls (64 cases, including 23 sarcoidosis patients, 19 pneumonia patients, and 22 other lung disease patients) and nonsmall cell lung cancer (NSCLC) patients (74 patients).

RESULTS

The different kits showed different recovery rates. Moreover, the ccfDNA present in plasma or stored in extraction buffer was stable after freeze-thawing, and the ccfDNA concentration remained consistent for 24 h at 4°C and for 12 h at room temperature. The patients with NSCLC-III/IV exhibited significantly higher ccfDNA levels than the patients with NSCLC-I/II (293 copies/μL vs. 190 copies/μL, p = 0.0339). However, no significant differences in the plasma ccfDNA levels were observed between the benign controls and NSCLC patients (241 copies/μL vs. 233 copies/μL, p > 0.05).

CONCLUSIONS

Variations in sample processing procedures led to variable results. The lack of differences between the NSCLC patients and benign controls indicates that further research is necessary to better characterize ccfDNA as a biomarker for diagnosing NSCLC.

Guarana improves behavior and inflammatory alterations triggered by methylmercury exposure: an in vivo fruit fly and in vitro neural cells study

Methylmercury (MeHg) is a well-known environmental pollutant associated with neurological and developmental deficits in animals and humans. However, epidemiological data showed that people living in the Amazon region although exposed to MeHg do not present these effects probably due to the protective effect of certain foods. We hypothesized here if guarana, a highly caffeinated fruit and consumed on a daily basis by Amazon people, could have some protective effect against MeHg toxicity using two complementary approaches. To assess locomotor impairment and sleep disruption, we used fruit fly (Drosophila melanogaster) model, and to evaluate neuroinflammation, we used human SH-SY5Y neural cells by measuring inflammatory cytokines levels. Results showed that guarana had a protective effect on the locomotor activity of male fruit flies reducing the excessive sleepiness caused by MeHg and increasing daily activity. Also, guarana increased the viability of flies and attenuated neural cells mortality. In addition, guarana reduced all pro-inflammatory cytokines levels increased by MeHg, along with caspase-1, caspase -3, caspase-8, and 8-dOHG levels, whereas increased the anti-inflammatory (IL-10) cytokine levels, which was decreased by MeHg. Our study provides new insights on the protective effects of guarana on the viability, locomotor activity, sleep, and activity patterns in vivo and the in vitro neuronal anti-inflammatory effect against MeHg toxicity.

Plasma cell-free DNA: a potential biomarker for early prediction of severe dengue

Background

Considerable progress has been made in dengue management, however the lack of appropriate predictors of severity has led to huge number of unwanted admissions mostly decided on the grounds of warning signs. Apoptosis related mediators, among others, are known to correlate with severe dengue (SD) although no predictive validity is established. The objective of this study was to investigate the association of plasma cell-free DNA (cfDNA) with SD, and evaluate its prognostic value in SD prediction at acute phase.

Methods

This was a hospital-based prospective cohort study conducted in Vietnam. All the recruited patients were required to be admitted to the hospital and were strictly monitored for various laboratory and clinical parameters (including progression to SD) until discharged. Plasma samples collected during acute phase (6–48 h before defervescence) were used to estimate the level of cfDNA.

Results

Of the 61 dengue patients, SD patients (n = 8) developed shock syndrome in 4.8 days (95% CI 3.7–5.4) after the fever onset. Plasma cfDNA levels before the defervescence of SD patients were significantly higher than the non-SD group (p = 0.0493). From the receiver operating characteristic (ROC) curve analysis, a cut-off of > 36.9 ng/mL was able to predict SD with a good sensitivity (87.5%), specificity (54.7%), and area under the curve (AUC) (0.72, 95% CI 0.55–0.88; p = 0.0493).

Conclusions

Taken together, these findings suggest that cfDNA could serve as a potential prognostic biomarker of SD. Studies with cfDNA kinetics and its combination with other biomarkers and clinical parameters would further improve the diagnostic ability for SD.

Electronic supplementary material

The online version of this article (10.1186/s12941-019-0309-x) contains supplementary material, which is available to authorized users.

Circulating cell-free DNA does not harbour a diagnostic benefit in cats with feline diffuse iris melanomas

OBJECTIVES

Feline diffuse iris melanoma (FDIM) is the most common malignant primary intraocular tumour in cats, with reported metastases rates between 19% and 63%. Currently, the only available diagnostic tool for a tentative diagnosis is histopathological examination of the enucleated eye. Therefore, the veterinary ophthalmologist is often faced with the dilemma of whether to enucleate an oftentimes visual eye or to continue monitoring, with the risk of metastases developing. In the past, cell-free DNA (cfDNA) gained more attention in human medicine, especially in the field of oncology. Prior studies have shown the use of cfDNA as diagnostic or prognostic markers in canine and human cancer patients. Therefore, the aim of this study was to investigate cfDNA concentration and integrity in cats with FDIMs compared with cats with benign iris naevi and without ocular abnormalities.

METHODS

cfDNA from plasma of cats with iris melanoma (n = 34), iris naevus (n = 30) and without ocular abnormalities (n = 32) were extracted. Primer and probes for feline amyloid beta precursor protein ( APP) and beta actin ( ACTB) were designed for amplicons of various lengths and quantitative PCRs of extracted cfDNA were performed to measure cfDNA concentration and integrity of the plasma samples. Differences of cfDNA concentrations and integrity levels between the three groups (iris melanoma, iris naevi and controls) were analysed using the Mann-Whitney U-test.

RESULTS

cfDNA concentration and integrity analysis revealed no significant differences between the cats with iris melanoma, iris naevus or the control group ( P >0.01). Cats with metastases showed similar cfDNA concentration and integrity to cats without metastases.

CONCLUSIONS AND RELEVANCE

cfDNA concentration and integrity seem to be insufficient as a diagnostic or prognostic marker in cats with FDIMs.

Neutrophil Activation and Early Features of NET Formation Are Associated With Dengue Virus Infection in Human

The involvement of the immune system in the protection and pathology of natural dengue virus (DENV) has been extensively studied. However, despite studies that have referred to activation of neutrophils in DENV infections, the exact roles of neutrophils remain elusive. Here, we explored the phenotypic and functional responses of neutrophils in a cohort of adult dengue patients. Results indicated that during an acute DENV infection, neutrophils up-regulate CD66b expression, and produce a more robust respiratory response as compared with that in convalescent or healthy individuals; this confirmed in vivo neutrophil activation during DENV infection. Spontaneous decondensation of nuclei, an early event of neutrophil extracellular trap (NET) formation, was also markedly increased in cells isolated from DENV-infected patients during the acute phase of the infection. In vitro incubation of NETs with DENV-2 virus significantly decreased DENV infectivity. Interestingly, increased levels of NET components were found in the serum of patients with more severe disease form-dengue hemorrhagic fever (DHF), but not uncomplicated dengue fever, during the acute phase of the infection. Levels of pro-inflammatory cytokines IL-8 and TNFα were also increased in DHF patients as compared with those in healthy and DF subjects. This suggested that NETs may play dual roles during DENV infection. The increased ability for NET formation during acute DENV infection appeared to be independent of PAD4-mediated histone H3 hyper-citrullination. Our study suggests that neutrophils are involved in immunological responses to DENV infection.

Sulfamethoxazole derivatives complexed with metals: a new alternative against biofilms of rapidly growing mycobacteria

Biofilms are considered important sources of infections on biomedical surfaces, and most infections involving biofilm formation are associated with medical device implants. Therefore, there is an urgent need for new antimicrobial compounds that can combat microbial resistance associated with biofilm formation. In this context, this work aimed to evaluate the antibiofilm action of sulfamethoxazole complexed with Au, Cd, Cu, Ni and Hg on rapidly growing mycobacteria (RGM), as well as to evaluate their safety through cytotoxic assays. The results demonstrate potentiation of the novel compounds in antibiofilm activity, mainly in the complex with Au, which was able to completely inhibit biofilm formation and had the capacity to destroy the biofilm at all the concentrations tested. All cytotoxic data suggest that the majority of sulfamethoxazole metallic derivatives are antimicrobial alternatives, as well as safe molecules, which could be used as potential therapeutic agents for bacterial and biofilm elimination.

Low mitochondrial DNA copy number of resected cecum appendix correlates with high severity of acute appendicitis

BACKGROUND/PURPOSE

The roles of mitochondrial DNA alterations in acute appendicitis (AA) remain unclear. We evaluated the alterations of mtDNA copy number and mtDNA integrity [proportion of mtDNA templates without 8-hydroxyl-2'-deoxyguanosine (8-OHdG)] of the resected cecum appendixes in clinically suspected acute appendicitis (CSAA).

METHODS

A total of 228 CSAA patients, including 50 harbored negative AA (NAA), 155 true AA (TAA) without rupture and 23 TAA with rupture, who underwent appendectomies were enrolled. Tissues of resected cecum appendixes from the paraffin-embedded pathological blocks were subjected to DNA extraction, and their mtDNA copy number and mtDNA integrity were determined by quantitative real-time polymerase chain reaction (Q-PCR).

RESULTS

During the progression of disease severity from NAA to TAA without rupture and further TAA with rupture, increases of white blood cell (WBC) counts (p = 0.001), positive bacterial culture rates in turbid ascites (p = 0.016) and area (p < 0.001)/or volume (p < 0.001) indices of resected cecum appendixes were noted among CSAA patients. On the contrary, decrease of mtDNA copy number (p = 0.003) was observed during disease progression of CSAA patients, especially in female patients (p = 0.007). Furthermore, lower mtDNA copy numbers were correlated with higher WBC counts (p = 0.001) and larger area (p = 0.003) or volume (p < 0.001) indices of the resected cecum appendixes. However, such an alteration was not observed in mtDNA integrity of resected cecum appendixes.

CONCLUSION

We conclude that a low mtDNA copy number of the resected cecum appendix may reflect high severity of acute appendicitis.

The Utility of Liquid Biopsy in Central Nervous System Malignancies

PURPOSE OF REVIEW

Liquid biopsy is a sampling of tumor cells or tumor nucleotides from biofluids. This review explores the roles of liquid biopsy for evaluation and management of patients with primary and metastatic CNS malignancies.

RECENT FINDINGS

Circulating tumor cell (CTC) detection has emerged as a relatively sensitive and specific tool for diagnosing leptomeningeal metastases. Circulating tumor DNA (ctDNA) detection can effectively demonstrate genetic markup of CNS tumors in the cerebrospinal fluid, though its role in managing CNS malignancies is less well-defined. The value of micro RNA (miRNA) detection in CNS malignancies is unclear at this time. Current standard clinical tools for the diagnosis and monitoring of CNS malignancies have limitations, and liquid biopsy may help address clinical practice and knowledge gaps. Liquid biopsy offers exciting potential for the diagnosis, prognosis, and treatment of CNS malignancies, but each modality needs to be studied in large prospective trials to better define their use.

Impact of Lipid-Inflammatory-Oxidative Metabolism on Auditory Skills after Hearing Aid Fitting in the Elderly

This study aimed to assess whether lipid-inflammatory-oxidative metabolism influences auditory processing skills, and whether they function in changing auditory performance after hearing aid fitting in the elderly. Twelve subjects with bilateral hearing loss were submitted to blood tests (to check their lipid-inflammatory-oxidative metabolism) and auditory processing skill tests. After 3 months of using the hearing aids, their auditory skills were re-evaluated and the data were correlated statistically. Oxidative stress levels mainly showed some impact on auditory temporal processing; such a relation and others should best be examined in further studies with larger populations.

Dengue virus activates cGAS through the release of mitochondrial DNA

Cyclic GMP-AMP synthetase (cGAS) is a DNA-specific cytosolic sensor, which detects and initiates host defense responses against microbial DNA. It is thus curious that a recent study identified cGAS as playing important roles in inhibiting positive-sense single-stranded RNA (+ssRNA) viral infection, especially since RNA is not known to activate cGAS. Using a dengue virus serotype 2 (DENV-2) vaccine strain (PDK53), we show that infection creates an endogenous source of cytosolic DNA in infected cells through the release of mitochondrial DNA (mtDNA) to drive the production of cGAMP by cGAS. Innate immune responses triggered by cGAMP contribute to limiting the spread of DENV to adjacent uninfected cells through contact dependent gap junctions. Our result thus supports the notion that RNA virus indirectly activates a DNA-specific innate immune signaling pathway and highlights the breadth of the cGAS-induced antiviral response.

Post-dengue acute disseminated encephalomyelitis: A case report and meta-analysis

BACKGROUND

Dengue is one of the most common infectious diseases. The aim of this study was to systematically review acute disseminated encephalomyelitis (ADEM) and to represent a new case.

METHODOLOGY/PRINCIPAL FINDINGS

We searched for articles in nine databases for case reports, series or previous reviews reporting ADEM cases in human. We used Fisher's exact and Mann-Whitney U tests. Classification trees were used to find the predictors of the disease outcomes. We combined findings using fixed- and random-effects models. A 13-year-old girl was admitted to the hospital due to fever. She has a urinary retention. The neurological examinations revealed that she became lethargic and quadriplegic. She had upper limbs weakness and lower limbs complete paraplegia. Her status gradually improved after the treatment. She was nearly intact with the proximal part of her legs had a mild weakness in discharge. The prevalence of ADEM among dengue patients was 0.4% [95% confidence intervals (95% CI) 0.1-2.5%], all neurological disorders among dengue was 2.6% [95% CI 1.8-3.8%], and ADEM among neurological disorders was 6.8% [95% CI 3.4-13%]. The most frequent manifestation of ADEM was altered sensorium/consciousness (58%), seizures and urination problems (35%), vision problems (31%), slurred speech (23%), walk problems (15%) then ataxia (12%). There was a significant difference between cases having complete recovery or bad outcomes in the onset day of neurological manifestations being earlier and in temperature being higher in cases having bad outcomes (p-value < 0.05). This was confirmed by classification trees which included these two variables.

CONCLUSIONS/SIGNIFICANCE

The prevalence of ADEM among dengue and other dengue-related neurological disorders is not too rare. The high fever of ADEM cases at admission and earlier onset day of neurological manifestations are associated with the bad outcomes.

ALA16VAL-MnSOD gene polymorphism and stroke: Association with dyslipidemia and glucose levels

Stroke risk has been associated to the progression of carotid plaques due to high glucose levels and lipid accumulation, which are greatly associated to cerebral injury, brain oxidative stress, and apoptosis. The ALA16VAL-MnSOD gene single nucleotide polymorphism (SNP) has shown to modulate risk factors of several metabolic and vascular diseases, such as blood glucose (GLU) and lipid levels. However, the association of these factors in stroke patients has not been studied to date. Thus, we evaluated the influence of the Ala16Val-MnSOD SNP on lipid profile, GLU levels, oxidative and DNA damage of 44 patients in a late phase of stroke (>6months). The statistical analysis showed a greater proportion of VV carries in stroke patients. The results also indicated that stroke patients had higher cholesterol (CHO) and GLU levels when compared to healthy counterparts. Interestingly, V allele carriers with stroke showed higher levels of CHO and GLU when compared to AA stroke and healthy counterparts. Our findings suggest that oxidative stress markers are still increased even after 6 months of cerebral injury. Furthermore, we propose that the Ala16Val-MnSOD SNPs may contribute to hypercholesterolemia and higher GLU levels, increasing the risk to neurovascular events that may lead to stroke.

Platelet proteome reveals novel pathways of platelet activation and platelet-mediated immunoregulation in dengue

Dengue is the most prevalent human arbovirus disease worldwide. Dengue virus (DENV) infection causes syndromes varying from self-limiting febrile illness to severe dengue. Although dengue pathophysiology is not completely understood, it is widely accepted that increased inflammation plays important roles in dengue pathogenesis. Platelets are blood cells classically known as effectors of hemostasis which have been increasingly recognized to have major immune and inflammatory activities. Nevertheless, the phenotype and effector functions of platelets in dengue pathogenesis are not completely understood. Here we used quantitative proteomics to investigate the protein content of platelets in clinical samples from patients with dengue compared to platelets from healthy donors. Our assays revealed a set of 252 differentially abundant proteins. In silico analyses associated these proteins with key molecular events including platelet activation and inflammatory responses, and with events not previously attributed to platelets during dengue infection including antigen processing and presentation, proteasome activity, and expression of histones. From these results, we conducted functional assays using samples from a larger cohort of patients and demonstrated evidence for platelet activation indicated by P-selectin (CD62P) translocation and secretion of granule-stored chemokines by platelets. In addition, we found evidence that DENV infection triggers HLA class I synthesis and surface expression by a mechanism depending on functional proteasome activity. Furthermore, we demonstrate that cell-free histone H2A released during dengue infection binds to platelets, increasing platelet activation. These findings are consistent with functional importance of HLA class I, proteasome subunits, and histones that we found exclusively in proteome analysis of platelets in samples from dengue patients. Our study provides the first in-depth characterization of the platelet proteome in dengue, and sheds light on new mechanisms of platelet activation and platelet-mediated immune and inflammatory responses.

Dengue is the most frequent hemorrhagic viral disease and re-emergent infection in the world. Recent decades were marked by a progressive global expansion of the infection including a higher frequency of severe dengue. Currently there is no effective vaccinal coverage or specific therapies, while efforts aimed at vector control have failed to stop the progression of epidemics and expansion of the disease. An increased understanding of the molecular physiology is of paramount importance for the establishment of new therapeutic targets and better clinical management. Dengue fever is characterized by thrombocytopenia and vascular leak. Although thrombocytopenia is a hallmark of dengue, the molecular phenotype and activities of platelets in the pathogenesis of dengue is not well elucidated. This work characterizes the proteome of platelets isolated from patients with dengue and includes validation of functionally-linked protein networks that we identified, using samples from a larger cohort of dengue patients. Moreover, in vitro experiments revealed activities of platelets that have recognized importance to dengue pathogenesis, including chemokine release, antigen presentation, and proteasome activity. Finally, our results identify circulating histones as a novel mechanism of platelet activation in dengue. These findings provide new evidence for platelet immune activities in dengue illness, and mark an advance in the understanding of this disease.

Circulating Tumor DNA as Biomarkers for Cancer Detection

Detection of circulating tumor DNAs (ctDNAs) in cancer patients is an important component of cancer precision medicine ctDNAs. Compared to the traditional physical and biochemical methods, blood-based ctDNA detection offers a non-invasive and easily accessible way for cancer diagnosis, prognostic determination, and guidance for treatment. While studies on this topic are currently underway, clinical translation of ctDNA detection in various types of cancers has been attracting much attention, due to the great potential of ctDNA as blood-based biomarkers for early diagnosis and treatment of cancers. ctDNAs are detected and tracked primarily based on tumor-related genetic and epigenetic alterations. In this article, we reviewed the available studies on ctDNA detection and described the representative methods. We also discussed the current understanding of ctDNAs in cancer patients and their availability as potential biomarkers for clinical purposes. Considering the progress made and challenges involved in accurate detection of specific cell-free nucleic acids, ctDNAs hold promise to serve as biomarkers for cancer patients, and further validation is needed prior to their broad clinical use.

Criteria of "persistent vomiting" in the WHO 2009 warning signs for dengue case classification

INTRODUCTION

Dengue is a viral disease that spreads rapidly in the tropic and subtropic regions of the world and causes 22,000 deaths annually. In 2009, the World Health Organization (WHO) released a new classification of dengue infections, which divided them into three categories: dengue without warning sign (D), dengue with warning sign (DWS), and severe dengue (SD). However, researchers have been using different criteria to define persistent vomiting; therefore, we aimed to evaluate the ability of the number of vomiting times in early prediction of SD development among D/DWS patients.

METHOD

A hospital-based cohort study was conducted in Ben Tre-south of Vietnam. We enrolled confirmed dengue patients with D and DWS at admission. The final classification was determined on the discharged day for every patient based on the classification of WHO 2009 without using vomiting symptom, using the receiver operating characteristic (ROC) curve to evaluate the ability of the number of vomiting times in early prediction of SD development among D/DWS patients.

RESULT

The prevalence of vomiting symptom was higher in SD group than D/DWS group (92 versus 46 %, p = 0.006), and the median of the number of vomiting times was higher in SD group than D/DWS group (2.5 versus 0, p = 0.001). To distinguish SD from D/DWS, the ROC curve of the number of vomiting episodes showed that the area under the curve was 0.77; with the cut point of two, the sensitivity and specificity were 92 and 52 %, respectively.

DISCUSSION

The number of vomiting times could be a good clinical sign which can early predict SD from the group of D/DWS. We suggest the definition of persistent vomiting should be vomiting two times or more per day.

A Proteomic Approach Identifies Candidate Early Biomarkers to Predict Severe Dengue in Children

BACKGROUND

Severe dengue with severe plasma leakage (SD-SPL) is the most frequent of dengue severe form. Plasma biomarkers for early predictive diagnosis of SD-SPL are required in the primary clinics for the prevention of dengue death.

METHODOLOGY

Among 63 confirmed dengue pediatric patients recruited, hospital based longitudinal study detected six SD-SPL and ten dengue with warning sign (DWS). To identify the specific proteins increased or decreased in the SD-SPL plasma obtained 6-48 hours before the shock compared with the DWS, the isobaric tags for relative and absolute quantification (iTRAQ) technology was performed using four patients each group. Validation was undertaken in 6 SD-SPL and 10 DWS patients.

PRINCIPAL FINDINGS

Nineteen plasma proteins exhibited significantly different relative concentrations (p<0.05), with five over-expressed and fourteen under-expressed in SD-SPL compared with DWS. The individual protein was classified to either blood coagulation, vascular regulation, cellular transport-related processes or immune response. The immunoblot quantification showed angiotensinogen and antithrombin III significantly increased in SD-SPL whole plasma of early stage compared with DWS subjects. Even using this small number of samples, antithrombin III predicted SD-SPL before shock occurrence with accuracy.

CONCLUSION

Proteins identified here may serve as candidate predictive markers to diagnose SD-SPL for timely clinical management. Since the number of subjects are small, so further studies are needed to confirm all these biomarkers.

Prognostic value of circulating DNA levels in critically ill and trauma patients

The number of studies investigating circulating nucleic acids as potential biomarkers has increased in recent years. The detection of such biomarkers is a minimally invasive alternative for the diagnosis and prognosis of various clinical conditions. The value of circulating DNA levels as a predictive biomarker has been demonstrated in patients suffering from numerous acute pathologies that have a high risk of intensive care needs and in-hospital deaths. The mechanism by which circulating DNA levels increase in patients with these conditions remains unclear. In this review, we focused on the potential use of this biomarker for prognosis prediction in critically ill and trauma patients. The literature review was performed by searching MedLine using PubMed in the English language.

Relationship of plasma cell-free DNA level with mortality and prognosis in patients with Crimean-Congo hemorrhagic fever

Crimean-Congo hemorrhagic fever (CCHF) is a viral infection. Circulating plasma cell-free DNA (pcf-DNA) is a novel marker indicating cellular damage. So far, the role of pcf-DNA did not investigate in CCHF patients. In the current study, pcf-DNA levels were investigated in CCHF patients with different clinical severity grades to explore the relationship between circulating pcf-DNA level, virus load, and disease severity. Seventy-two patients were categorized as mild, intermediate, and severe based on severity grading scores. The pcf-DNA level was obtained from all participants on admission and from the survivors on the day of the discharge. The controls consisted of 31 healthy. Although the pcf-DNA level at admission was higher in patients than in the controls, the difference was not statistically significant (P = 0.291). However, at admission and in the convalescent period, the difference between pcf-DNA levels in mild, intermediate, and severe patient groups was significant. The pcf-DNA level in severe patients was higher than in the others. Furthermore, compared to survivors, non-survivors had higher pcf-DNA levels at admission (P = 0.001). A direct relationship was found between the pcf-DNA level and the viral load on the day of discharge in surviving patients. ROC curve analysis identified a pcf-DNA level of 0.42 as the optimal cut-off for prediction of mortality. The positive predictive value, negative predictive value, specificity, and sensitivity for predicting mortality was 100%, 72%, 100%, and 79%, respectively. In summary, our findings revealed that pcf-DNA levels may be used as a biomarker in predicting CHHF prognosis.

Biomarkers of severe dengue disease - a review

Dengue virus infection presents a wide spectrum of manifestations including asymptomatic condition, dengue fever (DF), or severe forms, such as dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS) in affected individuals. The early prediction of severe dengue in patients without any warning signs who may later develop severe DHF is very important to choose appropriate intensive supportive therapy since available vaccines for immunization are yet to be approved. Severe dengue responses include T and B cell activation and apoptosis, cytokine storm, hematologic disorders and complement activation. Cytokines, complement and other unidentified factors may transiently act on the endothelium and alter normal fluid barrier function of the endothelial cells and cause plasma leakage. In this review, the host factors such as activated immune and endothelial cells and their products which can be utilized as biomarkers for severe dengue disease are discussed.