The protonolysis and redox reactivity of a Ce(IV) carbonate complex supported by the Kläui tripodal ligand [(η-CH)Co{P(O)(OEt)}] (L) have been studied. Whereas treatment of [Ce(L)(CO)] () with RCOH afforded [Ce(L)(RCO)] ( = Me (), Ph (), 2-NOCH ()), the reaction of with PhCHCOH resulted in formation of a mixture of Ce(IV) () and Ce(III) () carboxylate species. In benzene in the dark, was slowly converted into via Ce(IV)-O(carboxylate) homolysis.
View Article and Find Full Text PDFInadvertent exposure to aristolochic acids (AAs) is causing chronic renal disease worldwide, with aristolochic acid I (AA-I) identified as the primary toxic agent. This study employed chemical methods to investigate the mechanisms underlying the nephrotoxicity and carcinogenicity of AA-I. Aristolochic acid II (AA-II), which has a structure similar to that of AA-I, was investigated with the same methods for comparison.
View Article and Find Full Text PDFThe cancer risk associated with aristolochic acid (AA) exposure through the consumption of AA-containing herbal medicine has received tremendous attention in the past decades. However, environmental exposure routes from the associated medicinal herb cultivation fields have received little attention. We reveal through liquid chromatography-tandem mass spectrometry analysis of over 400 soil samples collected from three different Aristolochiaceae herb cultivation fields that AAs, which are nephrotoxic and carcinogenic, and aristoloxazines (AXs), a family of recently identified neurotoxic and genotoxic AA analogues, are widespread pollutants in these areas.
View Article and Find Full Text PDFIn this study, we assessed the feasibility of using a surgical face mask as a sampling device to collect airborne antimicrobial resistance genes (ARGs). The method entails collection of ARG-bearing microbes on face masks, followed by their DNA extraction and quantification by qPCR analysis. Analysis of masks worn by volunteers showed an apparent mask wearing time-dependent accumulation of 16S rRNA gene and select ARGs trapped on masks, highlighting the applicability of the method in monitoring personal ARG exposure through inhalation.
View Article and Find Full Text PDFThis study addressed the development of a novel biomarker for 2-chlorobenzalmalononitrile (CS) gas exposure. Using liquid chromatographic and mass spectrometric techniques, we found that CS underwent rapid hydrolysis into 2-chlorobenzaldehyde (2-CBA), a highly reactive intermediate that reacted swiftly with endogenous cysteine (Cys) and Cys residues in proteins, producing a stable 2-(2-chlorophenyl)thiazolidine-4-carboxylic acid adduct (ClPh-SPro) in high yield, which may be used as a CS exposure dosimeter. In particular, it was found that most CS was rapidly hydrolyzed under physiologically relevant conditions, with over 90% of CS being converted into 2-CBA in as short as 20 min.
View Article and Find Full Text PDFIdentification of fish larvae based on morphology is typically limited to higher taxonomic ranks (e.g., family or order), as larvae possess few morphological diagnostic characters for precise discrimination to species.
View Article and Find Full Text PDFAssessment of personal formaldehyde (FA) exposure is most commonly carried out using formate as a biomarker, as it is the major product from FA metabolism. However, formate could also have originated from the metabolism of other endogenous and exogenous substances or from dietary intake, which may give rise to overestimated results with regard to FA exposure. We have developed and validated a liquid chromatography-tandem mass spectrometry (LC-MS/MS) coupled with an isotope-dilution method for rigorous quantitation of two major urinary FA conjugation products: thioproline (SPro) and thioprolinyl glycine (SPro-Gly), formed in the reaction between FA and endogenous cysteine or cysteinyl glycine, respectively, as marker molecules to assess personal FA exposure.
View Article and Find Full Text PDFBalkan endemic nephropathy (BEN) is a chronic kidney disease that predominantly affects inhabitants of rural farming communities along the Danube River tributaries in the Balkans. Long-standing research has identified dietary exposure to aristolochic acids (AAs) as the principal toxicological cause. This study investigates the pathophysiological role of anemia in BEN, noting its earlier and more severe manifestation in BEN patients compared to those with other chronic kidney diseases.
View Article and Find Full Text PDFTens of thousands of people in southern Europe suffer from Balkan endemic nephropathy (BEN), and four times as many are at risk. Incidental ingestion of aristolochic acids (AAs), stemming from the ubiquitous(birthwort) weed in the region, leads to DNA adduct-induced toxicity in kidney cells, the primary cause of BEN. Numerous cofactors, including toxic organics and metals, have been investigated, but all have shown small contributions to the overall BEN relative to non-BEN village distribution gradients.
View Article and Find Full Text PDFEmerging evidence showing urothelial cancer in herbalists is linked to aristolochic acid (AA) exposure; however, the exposure pathway remains unclear. Here, we show that dermal contact and inhalation of fine powders of AA-containing herbs are significant occupational AA exposure pathways for herbalists. We initiated the study by quantifying the amount of AA in the AA-containing powder deposited on gloves and face masks worn by the operators of an AA-containing herb grinding machine.
View Article and Find Full Text PDFBACKGROUND We present a case of metachronous cardiac and intramuscular metastases in a patient with a known history of radical nephroureterectomy for upper-tract urothelial carcinoma (UTUC). CASE REPORT A 58-year-old man had a history of metachronous renal pelvis urothelial carcinoma with prior left radical nephroureterectomy. He was also diagnosed with malignancy-associated deep vein thrombosis (DVT) and was on rivaroxaban.
View Article and Find Full Text PDFAccumulated evidence has shown that Balkan endemic nephropathy (BEN) is a multifactorial environmental disease, with exposure to aristolochic acids (AA), and the associated DNA adduct formation, as a key causative factor of BEN development. Here, we show that coexposure to arsenic, cadmium, and iron increases the DNA adduct formation of AA in cultured kidney cells, while exhibiting both an exposure concentration and duration dependence. In contrast, coexposure to calcium and copper showed a decreasing DNA adduct formation.
View Article and Find Full Text PDFThe regulation of polymorphonuclear leukocyte (PMN) function by mechanical forces encountered during their migration across restrictive endothelial cell junctions is not well understood. Using genetic, imaging, microfluidic, and in vivo approaches, we demonstrated that the mechanosensor Piezo1 in PMN plasmalemma induced spike-like Ca signals during trans-endothelial migration. Mechanosensing increased the bactericidal function of PMN entering tissue.
View Article and Find Full Text PDFBackground: Pregnancy-associated pulmonary embolism (PAPE) remains a significant cause of maternal mortality. Anticoagulation remains the mainstay of therapy for most pulmonary embolism (PE)-related pregnancies. However, in patients with haemodynamic compromise or those refractory to anticoagulation, management is challenging.
View Article and Find Full Text PDFWet age-related macular degeneration (AMD), characterized by leaky neovessels emanating from the choroid, is a main cause of blindness. As current treatments for wet AMD require regular intravitreal injections of anti-vascular endothelial growth factor (VEGF) biologics, there is a need for the development of less invasive treatments. Here, we designed an allosteric inhibitor of end binding-3 (EB3) protein, termed EBIN, which reduces the effects of environmental stresses on endothelial cells by limiting pathological calcium signaling.
View Article and Find Full Text PDFMicroplastics (MPs) pose a significant environmental concern, particularly for terrestrial fauna. In this study, earthworms were used as a model organism to investigate the ecotoxicological effects of short-term exposure to virgin MPs on changes in metabolome and gut microbiota. High-throughput untargeted metabolomics showed significant internal reactions in the earthworms' metabolic processes due to MPs exposure, even when no visible stress signs, such as changes in growth or mortality rates, were present.
View Article and Find Full Text PDFAristolochic acids (AAs) are nephrotoxic and carcinogenic nitrophenanthrene carboxylic acids produced naturally by plants from the and genera, which have been used extensively as herbal medicines. In addition to consuming AA-containing herbal medicinal products, there is emerging evidence that humans are also exposed to AA through the environment. In 2022, the World Health Organization (WHO) called for global action to remove AA exposure sources and to implement preventative measures against the development of AA-associated cancers.
View Article and Find Full Text PDFExposure to environmental tobacco smoke (ETS), which contains hundreds of toxic compounds, significantly increases the risk of developing many human diseases, including lung cancer. The most common method of assessing personal exposure to ETS-borne toxicants is by sampling sidestream smoke generated by a smoking machine through a sorbent tube or filter, followed by solvent extraction and instrumental analysis. However, the ETS sampled may not truly represent the ETS in the ambient environment, due to complicating factors from the smoke released by the burning end of the cigarette and from the absorption of the chemicals in the respiratory tract of the smoker.
View Article and Find Full Text PDFAm J Respir Cell Mol Biol
October 2023
Acute respiratory distress syndrome (ARDS) is a lung disease characterized by acute onset of noncardiogenic pulmonary edema, hypoxemia, and respiratory insufficiency. The current treatment for ARDS is mainly supportive in nature, providing a critical need for targeted pharmacological management. We addressed this medical problem by developing a pharmacological treatment for pulmonary vascular leakage, a culprit of alveolar damage and lung inflammation.
View Article and Find Full Text PDFPara-chloro-meta-xylenol (PCMX) is a synthetic antiseptic used extensively to control the spread of germs and viruses, and as a result, enormous amount of PCMX could be discharged to water environments through drainage. To investigate the extent of PCMX contamination, water samples were collected from rivers and coastal waters in Hong Kong, and PCMX concentrations were determined by a newly developed method using liquid chromatography-tandem mass spectrometry combined with stable isotope-dilution. We discovered widespread PCMX pollution in the water environment.
View Article and Find Full Text PDFBackground: Coronary cameral fistula is a rare cardiovascular anomaly, and usually needs advanced image modalities, such as computerized tomography and/or angiography, to confirm its existence. A few reports in the literature have addressed the role of medical ultrasound in the diagnosis of this disease, without a comprehensive summary of all the valuable echocardiographic features in its diagnosis.
Case Presentation: Hereby, we presented an 80-year-old lady with exertional dyspnea and angina.
Prolonged exposure to aristolochic acids (AAs) through AA-containing herbal medicine or AA-contaminated food is associated with the development of aristolochic acid nephropathy (AAN) and Balkan endemic nephropathy (BEN), both public health risks to which the World Health Organization is calling for global action to remove exposure sources. The AA exposure-induced DNA damage is believed to be related to both the nephrotoxicity and carcinogenicity of AA observed in patients suffering from BEN. While the chemical toxicology of AA is well-studied, we investigated in this study the understated effect of different nutrients, food additives, or health supplements on DNA adduct formation by aristolochic acid I (AA-I).
View Article and Find Full Text PDFProlonged exposure to aristolochic acid (AA) through AA-containing herbal medicines or AA-tainted food is putting a large portion of the global population at risk of developing renal fibrosis and tumors of the upper urinary tract. In an effort to better understand the organotropic property of AA, we studied the cytotoxicity, absorption, oxidative-stress inducing potential, and DNA adduct formation capability of aristolactam I (ALI), one of the major urinary metabolites of aristolochic acid I (AAI) in human cells. Despite ALI having a slightly lower cytotoxicity than that of AAI, the analysis revealed, for the first time, that ALI is bioaccumulated 900 times more than that of AAI inside cultured kidney cells.
View Article and Find Full Text PDFIdentification of high-risk carotid plaques in asymptomatic patients remains a challenging but crucial step in stroke prevention. The challenge is to accurately monitor the development of high-risk carotid plaques and promptly identify patients, who are unresponsive to best medical therapy, and hence targeted for carotid surgical interventions to prevent stroke. Inflammation is a key operator in destabilisation of plaques prior to clinical sequelae.
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