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1.
Kidney Int Rep ; 9(5): 1458-1472, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38707825

RESUMEN

Introduction: Sugarcane workers are exposed to potentially hazardous agrochemicals, including pesticides, heavy metals, and silica. Such occupational exposures present health risks and have been implicated in a high rate of kidney disease seen in these workers. Methods: To investigate potential biomarkers and mechanisms that could explain chronic kidney disease (CKD) among this worker population, paired urine samples were collected from sugarcane cutters at the beginning and end of a harvest season in Guatemala. Workers were then separated into 2 groups, namely those with or without kidney function decline (KFD) across the harvest season. Urine samples from these 2 groups underwent elemental analysis and untargeted metabolomics. Results: Urine profiles demonstrated increases in silicon, certain pesticides, and phosphorus levels in all workers, whereas heavy metals remained low. The KFD group had a reduction in estimated glomerular filtration rate (eGFR) across the harvest season; however, kidney injury marker 1 did not significantly change. Cross-harvest metabolomic analysis found trends of fatty acid accumulation, perturbed amino acid metabolism, presence of pesticides, and other known signs of impaired kidney function. Conclusion: Silica and certain pesticides were significantly elevated in the urine of sugarcane workers with or without KFD. Future work should determine whether long-term occupational exposure to silica and pesticides across multiple seasons contributes to CKD in these workers. Overall, these results confirmed that multiple exposures are occurring in sugarcane workers and may provide insight into early warning signs of kidney injury and may help explain the increased incidence of CKD among agricultural workers.

2.
Emerg Med Australas ; 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38807508

RESUMEN

OBJECTIVE: Vitamin B17 tablets are sold (online) as an alternative cancer therapy medication. Its use however is not benign, given that it is metabolised into hydrogen cyanide. We aimed to measure the number of calls received by the New South Wales Poisons Information Centre (NSW PIC) regarding Amygdalin exposures. METHODS: A retrospective review of all amygdalin/cyanogenic glycoside product ingestion exposure calls to NSW PIC between 2015 and 2022. RESULTS: There were 120 unique exposure calls. Eighty-two (68%) were regarding minor exposures, with the remaining 38 (32%) of calls involving patients who had either a signifcant history or symptoms to prompt referral to hospital or were already seeking advice from a treating hospital clinican. CONCLUSION: There is a significant burden of concern generated from the misuse of cyanogenic glycoside products for cancer prevention and treatment, which can result in hospital admission carrying significant health risk and expenditure.

3.
ACS Chem Neurosci ; 15(7): 1533-1547, 2024 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-38507813

RESUMEN

Neuroinflammation plays a crucial role in the development of neurodegenerative protein misfolding disorders. This category of progressive diseases includes, but is not limited to, Alzheimer's disease, Parkinson's disease, and prion diseases. Shared pathogenesis involves the accumulation of misfolded proteins, chronic neuroinflammation, and synaptic dysfunction, ultimately leading to irreversible neuronal loss, measurable cognitive deficits, and death. Presently, there are few to no effective treatments to halt the advancement of neurodegenerative diseases. We hypothesized that directly targeting neuroinflammation by downregulating the transcription factor, NF-κB, and the inflammasome protein, NLRP3, would be neuroprotective. To achieve this, we used a cocktail of RNA targeting therapeutics (SB_NI_112) shown to be brain-penetrant, nontoxic, and effective inhibitors of both NF-κB and NLRP3. We utilized a mouse-adapted prion strain as a model for neurodegenerative diseases to assess the aggregation of misfolded proteins, glial inflammation, neuronal loss, cognitive deficits, and lifespan. Prion-diseased mice were treated either intraperitoneally or intranasally with SB_NI_112. Behavioral and cognitive deficits were significantly protected by this combination of NF-κB and NLRP3 downregulators. Treatment reduced glial inflammation, protected against neuronal loss, prevented spongiotic change, rescued cognitive deficits, and significantly lengthened the lifespan of prion-diseased mice. We have identified a nontoxic, systemic pharmacologic that downregulates NF-κB and NLRP3, prevents neuronal death, and slows the progression of neurodegenerative diseases. Though mouse models do not always predict human patient success and the study was limited due to sample size and number of dosing methods utilized, these findings serve as a proof of principle for continued translation of the therapeutic SB_NI_112 for prion disease and other neurodegenerative diseases. Based on the success in a murine prion model, we will continue testing SB_NI_112 in a variety of neurodegenerative disease models, including Alzheimer's disease and Parkinson's disease.


Asunto(s)
Enfermedad de Alzheimer , Enfermedades Neurodegenerativas , Enfermedad de Parkinson , Enfermedades por Prión , Priones , Deficiencias en la Proteostasis , Humanos , Ratones , Animales , Enfermedades Neurodegenerativas/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , FN-kappa B/metabolismo , Enfermedad de Alzheimer/metabolismo , Enfermedades Neuroinflamatorias , Regulación hacia Abajo , Enfermedad de Parkinson/metabolismo , Neuronas/metabolismo , Enfermedades por Prión/tratamiento farmacológico , Enfermedades por Prión/metabolismo , Priones/metabolismo , Inflamación/metabolismo , Deficiencias en la Proteostasis/tratamiento farmacológico , Deficiencias en la Proteostasis/metabolismo
4.
Inhal Toxicol ; : 1-16, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38349733

RESUMEN

Sugarcane is the most widely cultivated crop in the world, with equatorial developing nations performing most of this agriculture. Burning sugarcane is a common practice to facilitate harvest, producing extremely high volumes of respirable particulate matter in the process. These emissions are known to have deleterious effects on agricultural workers and nearby communities, but the extent of this exposure and potential toxicity remain poorly characterized. As the epidemicof chronic kidney disease of an unknown etiology (CKDu) and its associated mortality continue to increase along with respiratory distress, there is an urgent need to investigate the causes, determine viable interventions to mitigate disease andimprove outcomes for groups experiencing disproportionate impact. The goal of this review is to establish the state of available literature, summarize what is known in terms of human health risk, and provide recommendations for what areas should be prioritized in research.

5.
Artículo en Inglés | MEDLINE | ID: mdl-38234297

RESUMEN

Background. Silica nanoparticles found in sugarcane ash have been postulated to be a toxicant contributing to chronic kidney disease of unknown etiology (CKDu). However, while the administration of manufactured silica nanoparticles is known to cause chronic tubulointerstitial disease in rats, the effect of administering sugarcane ash on kidney pathology remains unknown. Here we investigate whether sugarcane ash can induce CKD in rats. Methods. Sugarcane ash was administered for 13 weeks into the nares of rats (5 mg/day for 5d/week), and blood, urine and kidney tissues were collected at 13 weeks (at the end of ash administration) and in a separate group of rats at 24 weeks (11 weeks after stopping ash administration). Kidney histology was evaluated, and inflammation and fibrosis (collagen deposition) measured. Results. Sugarcane ash exposure led to the accumulation of silica in the kidneys, lungs, liver and spleen of rats. Mild proteinuria developed although renal function was largely maintained. However, biopsies showed focal glomeruli with segmental glomerulosclerosis, and tubulointerstitial inflammation and fibrosis that tended to worsen even after the ash administration had been stopped. Staining for the lysosomal marker, LAMP-1, showed decreased staining in ash administered rats consistent with lysosomal activation. Conclusion. Sugarcane ash containing silica nanoparticles can cause CKD in rats.

6.
Arthritis Rheumatol ; 76(3): 438-443, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37909388

RESUMEN

OBJECTIVE: Giant cell arteritis (GCA) is an age-related vasculitis. Prior studies have identified an association between GCA and hematologic malignancies (HMs). How the presence of somatic mutations that drive the development of HMs, or clonal hematopoiesis (CH), may influence clinical outcomes in GCA is not well understood. METHODS: To examine an association between CH and GCA, we analyzed sequenced exomes of 470,960 UK Biobank (UKB) participants for the presence of CH and used multivariable Cox regression. To examine the clinical phenotype of GCA in patients with and without somatic mutations across the spectrum of CH to HM, we performed targeted sequencing of blood samples and electronic health record review on 114 patients with GCA seen at our institution. We then examined associations between specific clonal mutations and GCA disease manifestations. RESULTS: UKB participants with CH had a 1.48-fold increased risk of incident GCA compared to UKB participants without CH. GCA risk was highest among individuals with cytopenia (hazard ratio [HR] 2.98, P = 0.00178) and with TET2 mutation (HR 2.02, P = 0.00116). Mutations were detected in 27.2% of our institutional GCA cohort, three of whom had HM at GCA diagnosis. TET2 mutations were associated with vision loss in patients with GCA (odds ratio 4.33, P = 0.047). CONCLUSIONS: CH increases risk for development of GCA in a genotype-specific manner, with the greatest risk being conferred by the presence of mutations in TET2. Somatic TET2 mutations likewise increase the risk of GCA-associated vision loss. Integration of somatic genetic testing in GCA diagnostics may be warranted in the future.


Asunto(s)
Dioxigenasas , Arteritis de Células Gigantes , Humanos , Arteritis de Células Gigantes/complicaciones , Mutación , Proteínas de Unión al ADN/genética
8.
Environ Health Perspect ; 131(12): 127018, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38147368

RESUMEN

BACKGROUND: Prenatal exposures to certain poly- and perfluoroalkyl substances (PFAS) are associated with reduced humoral responses to some childhood immunizations. OBJECTIVE: We estimated associations between prenatal PFAS exposure and child antibody titers for measles, mumps, rubella (MMR), and varicella after immunization. METHODS: We measured serum antibody titers of 145 children (4-8 y old) enrolled in the Healthy Start cohort in Colorado, whose mothers had PFAS quantified mid-pregnancy (2009-2014). We used linear and logistic regression models to assess the relationship between five PFAS detected in >65% of mothers and continuous or non-high-censored ("low") antibody titers and quantile g-computation to evaluate the overall effect of the PFAS mixture. RESULTS: Median concentrations of individual PFAS were at or below the median reported among females in the United States. After receiving two vaccine doses, seropositive levels of antibodies were detected among most (93%-100%) children. Each log-unit increase in perfluorononanoate was associated with 2.09 [95% confidence interval (CI): 1.13, 3.87] times higher odds of a low measles titer, and each log-unit increase in perfluorooctanoate was associated with 2.46 (95% CI: 1.28, 4.75) times higher odds of a low mumps titer. Odds ratios for all other PFAS were elevated, but CIs included the null. Each quartile increase in the PFAS mixture was associated with 1.35 (95% CI: 0.80, 2.26) times higher odds of a low measles titer and 1.44 (95% CI: 0.78, 2.64) times higher odds of a low mumps titer. No significant associations were observed between PFAS and varicella or rubella antibodies. In stratified analyses, associations were negative among female children, except for perfluorohexane sulfonate and varicella, whereas they were positive among males. DISCUSSION: Some prenatal PFAS were associated with lower antibody titers among fully immunized children. The potential for immunotoxic effects of PFAS requires further investigation in a larger study, because exposure is ubiquitous globally. https://doi.org/10.1289/EHP12863.


Asunto(s)
Varicela , Fluorocarburos , Sarampión , Paperas , Efectos Tardíos de la Exposición Prenatal , Rubéola (Sarampión Alemán) , Vacunas , Niño , Masculino , Embarazo , Femenino , Humanos , Preescolar , Varicela/epidemiología , Paperas/epidemiología , Efectos Tardíos de la Exposición Prenatal/epidemiología , Rubéola (Sarampión Alemán)/epidemiología
9.
Clin Toxicol (Phila) ; 61(9): 644-648, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37917043

RESUMEN

INTRODUCTION: Thebaine is an alkaloid in poppy seeds that is neurotoxic to animals. Data on its clinical effects and toxicokinetics in people are minimal. In 2022, poppy seeds high in thebaine entered the Australian food market, and people consuming tea made from these poppy seeds developed poisoning. METHODS: Three patients who drank poppy seed tea and developed neuromuscular toxicity consented for thebaine to be quantitated in serial blood samples. Blood samples were analyzed by liquid chromatography with high-resolution mass spectrometry. RESULTS: Case 1: A man in his 60s presented with drowsiness, vomiting, malaise and myoclonus. He developed metabolic acidosis with hyperlactataemia, acute kidney injury requiring haemodialysis, convulsions, rhabdomyolysis, and was in the hospital for 18 days. The admission thebaine blood concentration was 2.1 mg/L, and the apparent elimination half-life was 14.8 h. Case 2: A man in his 30s presented with myoclonus, rigidity, vomiting, and dizziness. He developed metabolic acidosis with hyperlactataemia, acute kidney injury, and myalgias. The admission thebaine blood concentration was 4.1 mg/L, and the apparent elimination half-life was 11.6 h. Case 3: A man in his 30s presented with myoclonus, rigidity, clonus, diaphoresis, and abdominal pain. The admission thebaine blood concentration was 2.2 mg/L, and the apparent elimination half-life was 8.3 h. DISCUSSION: Neuromuscular toxicity, metabolic acidosis with hyperlactataemia, acute kidney injury, and gastrointestinal symptoms were prominent clinical features in these patients after drinking poppy seed tea. Effects persisted for days, and all survived, despite thebaine concentrations far exceeding those in published forensic reports, although human data are sparse. Compared to rats, the thebaine apparent elimination half-life is much longer in humans who develop symptoms at lower concentrations. CONCLUSIONS: Despite relatively high thebaine blood concentrations and moderate to severe poisoning, outcomes were favourable with early presentations. It is possible that acute kidney injury prolongs the apparent elimination half-life of thebaine.


Asunto(s)
Acidosis , Lesión Renal Aguda , Mioclonía , Papaver , Masculino , Humanos , Animales , Ratas , Tebaína/análisis , Morfina , Papaver/química , Toxicocinética , Australia , Semillas/química , , Lesión Renal Aguda/inducido químicamente , Vómitos/inducido químicamente
10.
ACS Biomater Sci Eng ; 9(12): 6902-6914, 2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-38014849

RESUMEN

Cancer treatment is one of the major health problems that burden our society. According to the American Cancer Society, over 1.9 million new cancer cases and ∼0.6 million deaths from cancer are expected in the US in 2023. Therapeutic targeting is considered to be the gold standard in cancer treatment. However, when a tumor grows beyond a critical size, its vascular system differentiates abnormally and erratically, creating a heterogeneous endothelial barrier that further restricts drug delivery into tumors. While several methods exist, these prompt tumor migration and the appearance of new metastatic sites. Herein, we propose an innovative method based on magneto-mechanical actuation (MMA) to induce endothelial permeability. This method employs FDA-approved PEGylated superparamagnetic iron oxide nanoparticles (PEG-SPIONs) and alternating nonheating magnetic fields. MMA lies in the translation of magnetic forces into mechanical agitation. As a proof of concept, we developed a 2D cell culture model based on human umbilical vein endothelial cells (HUVEC), which were incubated with PEG-SPIONs and then exposed to different magnetic doses. After adjusting the particle concentration, incubation times, and parameters (amplitude, frequency, and exposure time) of the magnetic field generator, we induced actin filament remodeling and subsequent vascular endothelial-cadherin junction disruption. This led to transient gaps in cell monolayers, through which fluorescein isothiocyanate-dextran was translocated. We observed no cell viability reduction for 3 h of particle incubation up to a concentration of 100 µg/mL in the presence and absence of magnetic fields. For optimal permeability studies, the magnetic field parameters were adjusted to 100 mT, 65 Hz, and 30 min in a pulse mode with 5 min OFF intervals. We found that the endothelial permeability reached the highest value (33%) when 2 h postmagnetic field treatment was used. To explain these findings, a magneto-mechanical transduced stress mechanism mediated by intracellular forces was proposed. This method can open new avenues for targeted drug delivery into anatomic regions within the body for a broad range of disease interventions.


Asunto(s)
Sistemas de Liberación de Medicamentos , Neoplasias , Estados Unidos , Humanos , Células Endoteliales de la Vena Umbilical Humana , Permeabilidad
12.
Environ Res ; 239(Pt 1): 117311, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37805178

RESUMEN

EXPOSURE TO POLY: and perfluoroalkyl substances (PFAS) in early life may increase the risk of childhood asthma, but evidence has been inconsistent. We estimated associations between maternal serum concentrations of PFAS during pregnancy and clinician-diagnosed asthma incidence in offspring through age eight. We included 597 mother-child pairs with PFAS quantified in mid-pregnancy serum and childhood medical records reviewed for asthma diagnoses. We used separate Cox proportional hazards models to assess the relationship between log-transformed concentrations of five PFAS and the incidence of asthma. We estimated associations between the PFAS mixture and clinician-diagnosed asthma incidence using quantile-based g-computation. PFAS concentrations were similar to those among females in the US general population. Seventeen percent of children (N = 104) were diagnosed with asthma during follow-up. Median (interquartile range) duration of follow-up was 4.7 (4.0, 6.2) years, and median age at asthma diagnosis was 1.7 (0.9, 2.8) years. All adjusted hazard ratios (HRs) were elevated, but all 95% confidence intervals (CI) included the null. The HR (95% CI) of asthma for a one-quartile increase in the PFAS mixture was 1.17 (0.86, 1.61). In this cohort of children followed to eight years of age, prenatal PFAS concentrations were not significantly associated with incidence of clinician-diagnosed asthma.


Asunto(s)
Asma , Fluorocarburos , Efectos Tardíos de la Exposición Prenatal , Femenino , Embarazo , Humanos , Preescolar , Incidencia , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Efectos Tardíos de la Exposición Prenatal/epidemiología , Asma/inducido químicamente , Asma/epidemiología , Familia , Fluorocarburos/toxicidad
13.
Clin Toxicol (Phila) ; 61(9): 639-643, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37855308

RESUMEN

INTRODUCTION: Poppy seed tea is used for its opioid effects and contains multiple opium alkaloids, including morphine, codeine, papaverine, and thebaine. Animal studies indicate thebaine has strychnine-like properties, but there is limited literature describing human thebaine poisoning. We describe a cluster of acute thebaine poisoning in people ingesting tea made using poppy seeds with high thebaine content that entered the Australian food supply chain. METHODS: This is an observational study of patients poisoned after drinking poppy seed tea. Cases were identified by three prospective toxicovigilance systems: the Emerging Drug Network of Australia collaboration, the New South Wales Prescription, Recreational and Illicit Substance Evaluation program, and the Emerging Drugs Network of Australia Victoria study. We report characteristics of clinical toxicity in cases with reported ingestion of poppy seed tea and analytical confirmation of thebaine exposure. RESULTS: Forty cases presenting with multi-system toxicity following poppy seed tea ingestion were identified across seven Australian states/territories from November 2022 to January 2023. Blood testing in 23 cases confirmed high thebaine concentrations. All 23 were male (median age 35, range 16-71 years). All patients experienced muscle spasms. Rigidity was described in nine, convulsions in six, while rhabdomyolysis, acute kidney injury, and metabolic acidosis occurred in five patients. There were two cardiac arrests. The thebaine median admission blood concentration was 1.6 mg/L, with a range of 0.1-5.6 mg/L, and was the dominant opium alkaloid in all samples. Convulsions, acute kidney injury, metabolic acidosis, and cardiac arrest were associated with increasing median thebaine concentrations. Four patients were managed in the Intensive Care Unit, with two receiving continuous kidney replacement therapy (one also received intermittent haemodialysis) for kidney injury. There was one death. CONCLUSIONS: Thebaine toxicity, like strychnine poisoning, resulted in neuromuscular excitation characterized by muscle spasm, rigidity, and convulsions. Severe toxicity, including acute kidney injury, metabolic acidosis, and cardiac arrest, appears dose-dependent.


Asunto(s)
Acidosis , Lesión Renal Aguda , Paro Cardíaco , Papaver , Animales , Humanos , Masculino , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Femenino , Tebaína/análisis , Opio , Estudios Prospectivos , Estricnina , Morfina , Codeína , Semillas/química , Convulsiones , , Victoria
14.
Int J Drug Policy ; 121: 104178, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37776604

RESUMEN

BACKGROUND: There is growing concern, globally, regarding use of nitrous oxide (N2O) for intoxication purposes. This paper aims to examine trends in: (i) past six month N2O use among a sample of people who use regularly use ecstasy and/or other illicit stimulants (2003-2020); (ii) volume of N2O-related Google searches and social media posts (2009-2020); and (iii) N2O-related calls to Poisons Information Centres (PIC) (2004-2020). METHODS: Data were obtained from annual interviews with sentinel samples of Australians aged ≥16 years who used ecstasy and/or other illicit stimulants ≥monthly and resided in a capital city (∼800 each year); Google search activity; social media posts; and exposure calls to four PIC. RESULTS: Among samples of people who regularly use ecstasy and/or other illicit stimulants, past six-month N2O use increased 10% each year from 2009 to 2020, with the sharpest increase observed between 2015 and 2018 (25.4% p/year; 95% CI: 14.6-37.1). Frequency and quantity of N2O use remained stable and low. Google search probabilities increased by 1.8% each month from January 2009 and December 2019 (95% CI: 1.5-2.2), with the sharpest increase observed between July 2016 to December 2017 (6.0% p/month; 95% CI: 4.4-7.5). Social media posts increased 2.0% per month from January 2009 and December 2019 (95% CI: 1.1-3.0), with the sharpest increase observed between March and October 2017 (19.2% p/month; 95% CI: 1.7-39.7). The number of N2O-related calls to Australian PIC increased sixfold between 2016 (16) and 2020 (111). CONCLUSIONS: Triangulation of various data sources indicate significant shifts in N2O use and harms in Australia. This includes increases in use, Google searches and social media posts, although these have plateaued in recent years, coupled with increased rates of harm. These findings correspond with evidence of a global increase in N2O use and harm, highlighting the need for education of both people who use N2O and health professionals.


Asunto(s)
Estimulantes del Sistema Nervioso Central , N-Metil-3,4-metilenodioxianfetamina , Humanos , Óxido Nitroso/efectos adversos , Fuentes de Información , Australia/epidemiología
15.
Mol Cell ; 83(15): 2753-2767.e10, 2023 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-37478846

RESUMEN

Nuclear hormone receptors (NRs) are ligand-binding transcription factors that are widely targeted therapeutically. Agonist binding triggers NR activation and subsequent degradation by unknown ligand-dependent ubiquitin ligase machinery. NR degradation is critical for therapeutic efficacy in malignancies that are driven by retinoic acid and estrogen receptors. Here, we demonstrate the ubiquitin ligase UBR5 drives degradation of multiple agonist-bound NRs, including the retinoic acid receptor alpha (RARA), retinoid x receptor alpha (RXRA), glucocorticoid, estrogen, liver-X, progesterone, and vitamin D receptors. We present the high-resolution cryo-EMstructure of full-length human UBR5 and a negative stain model representing its interaction with RARA/RXRA. Agonist ligands induce sequential, mutually exclusive recruitment of nuclear coactivators (NCOAs) and UBR5 to chromatin to regulate transcriptional networks. Other pharmacological ligands such as selective estrogen receptor degraders (SERDs) degrade their receptors through differential recruitment of UBR5 or RNF111. We establish the UBR5 transcriptional regulatory hub as a common mediator and regulator of NR-induced transcription.


Asunto(s)
Cromatina , Factores de Transcripción , Humanos , Ligandos , Cromatina/genética , Factores de Transcripción/metabolismo , Receptores Citoplasmáticos y Nucleares/genética , Ubiquitinas , Ubiquitina-Proteína Ligasas/genética
16.
Environ Pollut ; 332: 121951, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37301454

RESUMEN

Multiple epidemics of chronic kidney disease of an unknown etiology (CKDu) have emerged in agricultural communities around the world. Many factors have been posited as potential contributors, but a primary cause has yet to be identified and the disease is considered likely multifactorial. Sugarcane workers are largely impacted by disease leading to the hypothesis that exposure to sugarcane ash produced during the burning and harvest of sugarcane could contribute to CKDu. Estimated exposure levels of particles under 10 µm (PM10) have been found to be exceptionally high during this process, exceeding 100 µg/m3 during sugarcane cutting and averaging ∼1800 µg/m3 during pre-harvest burns. Sugarcane stalks consist of ∼80% amorphous silica and generate nano-sized silica particles (∼200 nm) following burning. A human proximal convoluted tubule (PCT) cell line was subjected to treatments ranging in concentration from 0.025 µg/mL to 25 µg/mL of sugarcane ash, desilicated sugarcane ash, sugarcane ash-derived silica nanoparticles (SAD SiNPs) or manufactured pristine 200 nm silica nanoparticles. The combination of heat stress and sugarcane ash exposure on PCT cell responses was also assessed. Following 6-48 h of exposure, mitochondrial activity and viability were found to be significantly reduced when exposed to SAD SiNPs at concentrations 2.5 µg/mL or higher. Oxygen consumption rate (OCR) and pH changes suggested significant alteration to cellular metabolism across treatments as early as 6 h following exposure. SAD SiNPs were found to inhibit mitochondrial function, reduce ATP generation, increase reliance on glycolysis, and reduce glycolytic reserve. Metabolomic analysis revealed several cellular energetics pathways (e.g., fatty acid metabolism, glycolysis, and TCA cycle) are significantly altered across ash-based treatments. Heat stress did not influence these responses. Such changes indicate that exposure to sugarcane ash and its derivatives can promote mitochondrial dysfunction and disrupt metabolic activity of human PCT cells.


Asunto(s)
Nanopartículas , Saccharum , Humanos , Dióxido de Silicio/toxicidad , Dióxido de Silicio/análisis , Riñón/química , Nanopartículas/toxicidad , Línea Celular
17.
Sci Rep ; 13(1): 5101, 2023 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-36991007

RESUMEN

Progressive massive pulmonary fibrosis among coal miners has unexpectedly increased. It would likely due to the greater generation of smaller rock and coal particles produced by powerful equipment used in modern mines. There is limited understanding of the relationship between micro- or nanoparticles with pulmonary toxicity. This study aims to determine whether the size and chemical characteristics of typical coal-mining dust contribute to cellular toxicity. Size range, surface features, morphology, and elemental composition of coal and rock dust from modern mines were characterized. Human macrophages and bronchial tracheal epithelial cells were exposed to mining dust of three sub- micrometer and micrometer size ranges at varying concentrations, then assessed for cell viability and inflammatory cytokine expression. Coal had smaller hydrodynamic size (180-3000 nm) compared to rock (495-2160 nm) in their separated size fractions, more hydrophobicity, less surface charge, and consisted of more known toxic trace elements (Si, Pt, Fe, Al, Co). Larger particle size had a negative association with in-vitro toxicity in macrophages (p < 0.05). Fine particle fraction, approximately 200 nm for coal and 500 nm for rock particles, explicitly induced stronger inflammatory reactions than their coarser counterparts. Future work will study additional toxicity endpoints to further elucidate the molecular mechanism causing pulmonary toxicity and determine a dose-response curve.


Asunto(s)
Minas de Carbón , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Humanos , Tamaño de la Partícula , Polvo/análisis , Pulmón/química , Carbón Mineral/análisis
18.
Magn Reson Imaging ; 100: 43-54, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36933774

RESUMEN

This study provides insight into the advantages and disadvantages of using ferrite particles embedded in agar gel phantoms as MRI temperature indicators for low-magnetic field scanners. We compare the temperature-dependent intensity of MR images at low-field (0.2 T) to those at high-field (3.0 T). Due to a shorter T1 relaxation time at low-fields, MRI scanners operating at 0.2 T can use shorter repetition times and achieve a significant T2⁎ weighting, resulting in strong temperature-dependent changes of MR image brightness in short acquisition times. Although the signal-to-noise ratio for MR images at 0.2 T MR is much lower than at 3.0 T, it is sufficient to achieve a temperature measurement uncertainty of about ±1.0 °C at 37 °C for a 90 µg/mL concentration of magnetic particles.


Asunto(s)
Imagen por Resonancia Magnética , Termometría , Imagen por Resonancia Magnética/métodos , Termometría/métodos , Temperatura Corporal , Temperatura , Relación Señal-Ruido , Fantasmas de Imagen
19.
ACS Biomater Sci Eng ; 9(3): 1656-1671, 2023 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-36853144

RESUMEN

As the world braces to enter its fourth year of the coronavirus disease 2019 (COVID-19) pandemic, the need for accessible and effective antiviral therapeutics continues to be felt globally. The recent surge of Omicron variant cases has demonstrated that vaccination and prevention alone cannot quell the spread of highly transmissible variants. A safe and nontoxic therapeutic with an adaptable design to respond to the emergence of new variants is critical for transitioning to the treatment of COVID-19 as an endemic disease. Here, we present a novel compound, called SBCoV202, that specifically and tightly binds the translation initiation site of RNA-dependent RNA polymerase within the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genome, inhibiting viral replication. SBCoV202 is a Nanoligomer, a molecule that includes peptide nucleic acid sequences capable of binding viral RNA with single-base-pair specificity to accurately target the viral genome. The compound has been shown to be safe and nontoxic in mice, with favorable biodistribution, and has shown efficacy against SARS-CoV-2 in vitro. Safety and biodistribution were assessed using three separate administration methods, namely, intranasal, intravenous, and intraperitoneal. Safety studies showed the Nanoligomer caused no outward distress, immunogenicity, or organ tissue damage, measured through observation of behavior and body weight, serum levels of cytokines, and histopathology of fixed tissue, respectively. SBCoV202 was evenly biodistributed throughout the body, with most tissues measuring Nanoligomer concentrations well above the compound KD of 3.37 nM. In addition to favorable availability to organs such as the lungs, lymph nodes, liver, and spleen, the compound circulated through the blood and was rapidly cleared through the renal and urinary systems. The favorable biodistribution and lack of immunogenicity and toxicity set Nanoligomers apart from other antisense therapies, while the adaptability of the nucleic acid sequence of Nanoligomers provides a defense against future emergence of drug resistance, making these molecules an attractive potential treatment for COVID-19.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , COVID-19 , Genoma Viral , Nanomedicina , Nanoestructuras , Oligorribonucleótidos , Ácidos Nucleicos de Péptidos , SARS-CoV-2 , SARS-CoV-2/efectos de los fármacos , SARS-CoV-2/genética , COVID-19/virología , Tratamiento Farmacológico de COVID-19/efectos adversos , Tratamiento Farmacológico de COVID-19/métodos , Nanoestructuras/administración & dosificación , Nanoestructuras/efectos adversos , Nanoestructuras/uso terapéutico , Nanomedicina/métodos , Seguridad del Paciente , Ácidos Nucleicos de Péptidos/administración & dosificación , Ácidos Nucleicos de Péptidos/efectos adversos , Ácidos Nucleicos de Péptidos/farmacocinética , Ácidos Nucleicos de Péptidos/uso terapéutico , Oligorribonucleótidos/administración & dosificación , Oligorribonucleótidos/efectos adversos , Oligorribonucleótidos/farmacocinética , Oligorribonucleótidos/uso terapéutico , Animales , Ratones , Ratones Endogámicos BALB C , Técnicas In Vitro , Genoma Viral/efectos de los fármacos , Genoma Viral/genética , Distribución Tisular
20.
Addiction ; 118(7): 1370-1375, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36776135

RESUMEN

BACKGROUND AND AIMS: Inhalational misuse of volatile substances has been a significant public health concern because of the risk of sudden death and associated chronic complications such as encephalopathy. The Australian Government released a Consensus-based clinical practice guideline in 2011 on the management of volatile substance use in Australia, which noted a lack of available data particularly on harms. This study aimed to measure (1) the number of calls received by the New South Wales Poisons Information Centre (NSWPIC) regarding inhalational hydrocarbon exposures or poisonings and (2) the number of unintentional deaths reported to the National Coronial Information System (NCIS) in Australia. DESIGN, SETTING, CASES, MEASUREMENTS: We performed a retrospective review of all recreational inhalational hydrocarbon exposure calls to the NSWPIC between 1 January 2010 and 31 December 2020. A search was made of the NCIS database in all states and territories over the same period to determine the number of non-intentional inhalational hydrocarbon-related deaths in Australia. FINDINGS: Between January 2010 and December 2020, there were 752 primary calls made to the NSWPIC regarding hydrocarbon use or exposure. Age or age bracket was recorded in 748 cases, with 508 (67%) calls involving children or adolescents. Over the same time, there were 58 unintentional deaths involving the recreational use of inhalational hydrocarbons. The median age at death was 23 years (interquartile range = 15-30 years), and 72% (42 cases) were male. Cause of death was predominately acute suffocation/asphyxia, encephalopathy related to chronic use, cardiac arrest likely from sudden sniffing syndrome or thermal injuries secondary to unintentional fires sparked by the volatile agents. CONCLUSION: Although death and cardiac arrest are uncommon among people in Australia who misuse hydrocarbons for recreational use, the deaths and cardiac arrests tend to occur in adolescents.


Asunto(s)
Encefalopatías , Trastornos Relacionados con Sustancias , Niño , Adolescente , Humanos , Masculino , Adulto Joven , Adulto , Femenino , Australia , Nueva Gales del Sur , Estudios Retrospectivos , Hidrocarburos
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