Polychlorinated Biphenyls: A Review of Recent Updates on Food Safety and Environmental Monitoring, Health and Toxicological Implications, and Analysis.

A class of organic chemicals known as polychlorinated biphenyls (PCBs) consists of chlorine, hydrogen, and carbon atoms. High boiling points, chemical stability, non-flammability, and insulating properties have enabled them to be used in various industries. Because of their high toxicity, PCBs were one of the first industrial compounds to be banned from production. These compounds have high-fat solubility with bioaccumulation and biomagnification properties in the environment, food chain, and individuals. Hence, they may have an impact not only on individual organisms but ultimately on whole ecosystems. The main sources of PCB exposure are food and environmental pollutants. In the toxicology of PCBs, oxidative stress plays the most influential function. The induction of CYP1A1 due to the high affinity of PCBs for aryl hydrocarbon receptors is considered a trigger for oxidative stress. Production of reactive oxygen species and depletion of glutathione occur due to phase Ⅰ and Ⅱ metabolism, respectively. Thus, cellular redox balance may be disrupted in the presence of PCBs and their metabolites. Chronic and long-term exposure to these compounds can often lead to life-threatening diseases, like diabetes, obesity, cardiovascular and neurological diseases, cancer, and reproductive and endocrine disorders. We present the current knowledge of the routes of PCB exposure and bioaccumulation, the outlook regarding environmental and food safety, the potential role of PCBs in various diseases, the principal mechanisms responsible for PCB toxicity, and the main detection techniques used for PCBs.

Turmeric for Treatment of Irritable Bowel Syndrome: A Systematic Review of Population-Based Evidence.

Background: Irritable bowel syndrome (IBS) is a highly prevalent disorder of the gut interaction characterized by abdominal discomfort and pain associated with altered bowel habits in the absence of structural abnormalities. In spite of IBS' high prevalence and disease burden across the globe, no explanations have been given as to its underlying pathophysiology. As for the treatment of IBS, there is no specific medication, and the most beneficial treatment is usually supportive therapy. Recent animal and human studies have demonstrated the therapeutic potential of curcumin or turmeric in the treatment of IBS. Methods: We systematically reviewed all available evidence supporting curcumin and turmeric's therapeutic potential in relieving IBS symptoms in the present study. For this purpose, a database search was performed using curcumin, turmeric, and IBS and all their equivalents as of the search terms in Web of Science, Pub-Med, Scopus, Ovid, Embase, and Google Scholar from1990 up to Feb 2021. The investigation was then limited to clinical trials, and then nine articles were collected for data analysis. Results: The findings of the included literature showed that curcumin and turmeric alone or in combination with other medications could improve the severity of IBS as well as the quality of life among people who suffer from IBS symptoms. Conclusion: Overall, medications containing curcumin and turmeric extract due to these compounds' anti-inflammatory effects may improve IBS symptoms, particularly abdominal pain and life quality.

A Novel Approach for Designing Electrochemical Aptamer-Based Biosensor for Ultrasensitive Detection of Zearalenone as a Prevalent Estrogenic Mycotoxin.

BACKGROUND: Zearalenone is a well-known estrogenic mycotoxin produced by Fusarium species, a serious threat to the agricultural and food industries worldwide. Zearalenone, with its known metabolites, is a biomarker of exposure to certain fungi, primarily through food. It has considerable toxic effects on biological systems due to its carcinogenicity, mutagenicity, renal toxicity, teratogenicity, and immunotoxicity. INTRODUCTION: This study aims to design a simple, quick, precise, and cost-effective method on a biosensor platform to evaluate the low levels of this toxin in foodstuffs and agricultural products. METHODS: An aptamer-based electrochemical biosensor was introduced that utilizes screen-printed gold electrodes instead of conventional electrodes. The electrodeposition process was employed to develop a gold nanoparticle-modified surface to enhance the electroactive surface area. Thiolated aptamers were immobilized on the surface of gold nanoparticles, and subsequently, the blocker and analyte were added to the modified surface. In the presence of a redox probe, electrochemical characterization of differential pulse voltammetry, cyclic voltammetry, and electrochemical impedance spectroscopy were used to investigate the various stages of aptasensor fabrication. RESULTS: The proposed aptasensor for zearalenone concentration had a wide linear dynamic range covering the 0.5 pg/mL to 100 ng/mL with a 0.14 pg/mL detection limit. Moreover, this aptasensor had high specificity so that a non-specific analyte cannot negatively affect the selectivity of the aptasensor. CONCLUSION: Overall, due to its simple design, high sensitivity, and fast performance, this aptasensor showed a high potential for assessing zearalenone in real samples, providing a clear perspective for designing a portable and cost-effective device.

Cigarette smoke-induced toxicity consequences of intracellular iron dysregulation and ferroptosis.

Despite numerous studies on the mechanisms of cigarette smoking toxicity over the past three decades, some aspects remain obscure. Recent developments have drawn attention to some hopeful indicators that allow us to advance our awareness of cigarette-induced cell death. Ferroptosis is considered a type of governed death of cells distinguished by the iron-dependent lipid hydroperoxide deposition to fatal concentrations. Ferroptosis has been linked with pathological settings such as neurodegenerative diseases, cancer, heart attack, hemorrhagic stroke, traumatic brain injury, ischemia-reperfusion injury, and renal dysfunction. This review tries to explain the causal role of ferroptosis cascade in cigarette smoke-mediated toxicity and cell death, highlighting associations on potential action mechanisms and proposing suggestions for its detoxifying and therapeutic interventions.

Classification of the present pharmaceutical agents based on the possible effective mechanism on the COVID-19 infection.

OBJECTIVES: There are several types of research on the COVID-19 disease which have been conducting. It seems that prevailing over the pandemic would be achieved only by mastering over the virus pathophysiology. We tried to categorize the massive amount of available information for useful interpretation. EVIDENCE ACQUISITION: We searched databases with different keywords and search strategies that focus on virulence and pathophysiology of COVID-19. The present review has aimed to gather and categorize all implemented drugs based on the susceptible virulence mechanisms, and the pathophysiological events in the host cells, discussing and suggesting treatments. RESULTS: As a result, the COVID-19 lifecycle were categorized as following steps: "Host Cell Attachment" which is mainly conducted with ACE2 receptors and TMPRSS2 from the host cell and Spike (S) protein, "Endocytosis Pathway" which is performed mainly by clathrin-mediated endocytosis, and "Viral Replication" which contains translation and replication of RNA viral genome. The virus pathogenicity is continued by "Inflammatory Reactions" which mainly caused moderate to severe COVID-19 disease. Besides, the possible effective therapeutics' mechanism and the pharmaceutical agents that had at least one experience as a preclinical or clinical study on COVID-19 were clearly defined. CONCLUSION: The treatment protocol would be occasional based on the stage of the infection and the patient situation. The cocktail of medicines, which could affect almost all mentioned stages of COVID-19 disease, might be vital for patients with severe phenomena. The classification of the possible mechanism of medicines based on COVID-19 pathogenicity.

Biosensors and their applications in detection of organophosphorus pesticides in the environment.

This review discusses the past and recent advancements of biosensors focusing on detection of organophosphorus pesticides (OPs) due to their exceptional use during the last decades. Apart from agricultural benefits, OPs also impose adverse toxicological effects on animal and human population. Conventional approaches such as chromatographic techniques used for pesticide detection are associated with several limitations. A biosensor technology is unique due to the detection sensitivity, selectivity, remarkable performance capabilities, simplicity and on-site operation, fabrication and incorporation with nanomaterials. This study also provided specifications of the most OPs biosensors reported until today based on their transducer system. In addition, we highlighted the application of advanced complementary materials and analysis techniques in OPs detection systems. The availability of these new materials associated with new sensing techniques has led to introduction of easy-to-use analytical tools of high sensitivity and specificity in the design and construction of OPs biosensors. In this review, we elaborated the achievements in sensing systems concerning innovative nanomaterials and analytical techniques with emphasis on OPs.