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1.
Epilepsia ; 64(10): 2667-2678, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37522416

RESUMEN

OBJECTIVE: Bone metabolism can be influenced by a range of factors. We selected children with self-limited epilepsy with centrotemporal spikes (SeLECTS) and lifestyles similar to those of healthy children to control for the confounding factors that may influence bone metabolism. We aimed to identify the specific effects of epilepsy and/or anti-seizure medications (ASMs) on bone metabolism. METHODS: Patients with SeLECTS were divided into an untreated group and a monotherapy group, and the third group was a healthy control group. We determined the levels of various biochemical markers of bone metabolism, including procollagen type I nitrogenous propeptide (PINP), alkaline phosphatase (ALP), osteocalcin (OC), collagen type I cross-linked C-telopeptide (CTX), calcium, magnesium, phosphorus, parathyroid hormone (PTH), and vitamin D3 (VD3 ). RESULTS: A total of 1487 patients (from 19 centers) were diagnosed with SeLECTS; 1032 were analyzed, including 117 patients who did not receive any ASMs (untreated group), 643 patients who received only one ASM (monotherapy group), and 272 children in the healthy control group. Except for VD3 , other bone metabolism of the three groups were different (p < .001). Bone metabolism was significantly lower in the untreated group than the healthy control group (p < .05). There were significant differences between the monotherapy and healthy control group in the level of many markers. However, when comparing the monotherapy and untreated groups, the results were different; oxcarbazepine, levetiracetam, and topiramate had no significant effect on bone metabolism. Phosphorus and magnesium were significantly lower in the valproic acid group than the untreated group (adjusted p < .05, Cliff's delta .282-.768). CTX was significantly higher in the lamotrigine group than in the untreated group (adjusted p = .012, Cliff's delta = .316). SIGNIFICANCE: Epilepsy can affect many aspects of bone metabolism. After controlling epilepsy and other confounders that affect bone metabolism, we found that the effects of ASMs on bone metabolism differed. Oxcarbazepine, levetiracetam, and topiramate did not affect bone metabolism, and lamotrigine corrected some of the abnormal markers of bone metabolism in patients with epilepsy.

2.
Acta Radiol ; 63(3): 401-409, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33601894

RESUMEN

BACKGROUND: There was no previous report on the three-dimensional simultaneous non-contrast angiography and intra-plaque hemorrhage (3D-SNAP) magnetic resonance imaging (MRI) sequence to diagnose intracranial artery dissection (IAD). PURPOSE: To improve the diagnostic accuracy and guide the clinical treatment for IAD by elucidating its pathological features using 3D-SNAP MRI. MATERIAL AND METHODS: From January 2015 to September 2018, 113 patients with suspected IAD were analyzed. They were divided into IAD and non-IAD groups according to the spontaneous coronary artery dissection (SCAD) criteria. All patients underwent 3D-SNAP, 3D-TOF, T2W imaging, 3D-PD, 3D-T1W-VISTA, and 3D-T1WCE) using 3.0-T MRI; clinical data were collected. The IAD imaging findings (intramural hematoma, double lumen, intimal flap, aneurysmal dilatation, stenosis, or occlusion) in every sequence were analyzed. Receiver operating characteristic (ROC) curve analysis was used to evaluate the diagnostic efficiency of each sequence. RESULTS: There was a significant difference in the probability of intramural hematoma, relative signal intensity of intramural hematoma, double lumen, stenosis, or occlusion signs on 3D-TOF, T2W, 3D-PD, 3D-T1W-VISTA, 3D-SNAP, and 3D-T1WCE sequences (P<0.05). The 3D-SNAP and 3D-T1WCE sequences were most sensitive for diagnosing intramural hematoma and displaying double-lumen signs, respectively. The diagnostic efficiency of the 3D-SNAP sequence combined with 3D-T1WCE was the highest (area under the curve [AUC] 0.966). The AUC value of the 3D-SNAP sequence (AUC 0.897) was slightly inferior to that of 3D-T1W enhancement (AUC 0.903). CONCLUSION: 3D-SNAP MRI is a non-invasive and effective method and had the greatest potential among those methods tested for improving the diagnostic accuracy for IAD.


Asunto(s)
Disección Aórtica/diagnóstico por imagen , Angiografía Cerebral/métodos , Imagenología Tridimensional , Aneurisma Intracraneal/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Placa Aterosclerótica/diagnóstico por imagen , Adulto , Hemorragia Cerebral/diagnóstico por imagen , Femenino , Hematoma/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
3.
Zhongguo Dang Dai Er Ke Za Zhi ; 21(7): 670-675, 2019 Jul.
Artículo en Zh | MEDLINE | ID: mdl-31315766

RESUMEN

OBJECTIVE: To study the clinical characteristics and genetic variation of early-onset Charcot-Marie-Tooth disease (CMT). METHODS: Children with a clinical diagnosis of early-onset CMT were selected for the study. Relevant clinical data were collected, and electromyogram and CMT-related gene detection were performed and analyzed. RESULTS: A total of 13 cases of early-onset CMT were enrolled, including 9 males (69%) and 4 females (31%). The mean age at consultation was 4.0±2.1 years. Among them, 12 children (92%) had an age of onset less than 2 years, 9 children (69%) were diagnosed with CMT type 1 (including 6 cases of Dejerine-Sottas syndrome), 1 child (8%) with intermediate form of CMT, and 3 children (23%) with CMT type 2. The genetic test results of these 13 children showed 6 cases (46%) of PMP22 duplication mutation, 3 cases (23%) of MPZ gene insertion mutation and point mutation, 3 cases (23%) of MFN2 gene point mutation, and 1 case (8%) of NEFL gene point mutation. Eleven cases (85%) carried known pathogenic mutations and 2 cases (15%) had novel mutations. The new variant c.394C>G (p.P132A) of the MPZ gene was rated as "possibly pathogenic" and the new variant c.326A>G (p.K109R) of the MFN2 gene was rated as "pathogenic". CONCLUSIONS: Early-onset CMT is mainly caused by PMP22 gene duplication mutation and MPZ gene mutations. The clinical phenotype is mainly CMT type 1, among which Dejerine-Sottas syndrome accounts for a considerable proportion.


Asunto(s)
Enfermedad de Charcot-Marie-Tooth , Niño , Preescolar , Femenino , Pruebas Genéticas , Genotipo , Humanos , Masculino , Mutación
5.
BMC Infect Dis ; 16: 230, 2016 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-27230114

RESUMEN

BACKGROUND: Clinically mild encephalitis/encephalopathy with a reversible splenial lesion (MERS) is a clinico-radiological syndrome characterized by transient mild symptoms of encephalopathy and a reversible lesion in the splenium of the corpus callosum on magnetic resonance imaging (MRI). It is often triggered by infection. The common pathogens of MERS are viruses, especially influenza virus. However, Mycoplasma pneumoniae (M.pneumoniae) are relatively rare pathogens for MERS. CASE PRESENTATION: Here we report two paediatric cases of M.pneumoniae infection-induced MERS. The diagnosis of M.pneumoniae infection was established based on polymerase chain reaction (PCR) and specific serum antibodies (IgM). Both of the two patients presented with mild encephalopathy manifestations and recovered completely within a few days. The initial MRI showed a lesion in the central portion of the splenium of the corpus callosum, which completely resolved on the seventh and eighth day after admission for case 1 and case 2. Lumbar puncture was performed in both patients, which revealed no pleocytosis. In case 1, the patient had hyponatremia, peripheral facial nerve paralysis, and rash. To the best of our knowledge, it is the first MERS case associated with peripheral nerve damage. In case 2, interleukin-6(IL-6) was moderately increased in the cerebrospinal fluid (CSF). It suggested that IL-6 may play a role in the pathogenesis of M.pneumoniae-induced MERS. CONCLUSION: Our study enriches the available information on the pathogens of MERS and provides valuable data for better understanding of this syndrome.


Asunto(s)
Cuerpo Calloso/diagnóstico por imagen , Encefalitis/diagnóstico , Infecciones por Mycoplasma/diagnóstico , Mycoplasma pneumoniae/aislamiento & purificación , Antiinfecciosos/uso terapéutico , Azitromicina/uso terapéutico , Niño , Diagnóstico Diferencial , Encefalitis/sangre , Encefalitis/complicaciones , Encefalitis/diagnóstico por imagen , Cefalea/etiología , Humanos , Masculino , Infecciones por Mycoplasma/sangre , Infecciones por Mycoplasma/complicaciones , Infecciones por Mycoplasma/diagnóstico por imagen
7.
Chem Commun (Camb) ; 60(36): 4860, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38606575

RESUMEN

Correction for 'Controllable synthesis of star-shaped FeCoMnOx nanocrystals and their self-assembly into superlattices with low-packing densities' by Zhe Xia et al., Chem. Commun., 2024, 60, 3409-3412, https://doi.org/10.1039/D4CC00332B.

8.
Chem Commun (Camb) ; 60(25): 3409-3412, 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38440958

RESUMEN

We present a novel method for synthesizing monodisperse, star-shaped FeCoMnOx nanocrystals with tunable concavity. Through liquid-air interfacial assembly, these colloidal nanostars can form two-dimensional superlattices, which are characterized by low packing densities. Notably, the ability to adjust the degree of concavity of nanostars allows for the tuning of the packing symmetry of the assembled superlattices.

9.
J Chromatogr A ; 1718: 464723, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38341899

RESUMEN

The scientific literature is replete with analytical methods for the analysis of homocyclic aromatic compounds especially polycyclic aromatic hydrocarbons and their alkylated analogs. However, there is a paucity of methods for the analysis of nitrogen-, sulfur- and oxygen-containing polycyclic aromatic compounds (PACs). The lack of commercially available analytical standards, the presence of many structural derivatives and isomers and lack of certified reference materials all contribute to the inherent challenges in measuring these compounds. Gas chromatography coupled with a tandem mass spectrometer was used to develop two multiple reaction monitoring methods to detect and quantify fifty-three non-halogenated and halogenated hetero-polycyclic aromatic compounds (HPACs). Because of their greater polarity, strongly non-polar solvents typically employed to extract homocyclic PACs from sediment samples did not yield acceptable recoveries of our target analytes. By adding ethyl acetate to dichloromethane (50:50), recoveries of our target analytes using accelerated solvent extraction increased markedly. The performance characteristics of the validated method including accuracy [> than 67% for 46 (out of 53) analytes], inter- and intra-day precision [<30% for all analytes, (expressed as relative standard deviation)], limits of detection (0.1 to 2.3 ng/g) and quantitation (1.5 to 7.6 ng/g) imply that the method is fit for its intended purpose. A sediment sample from a known contaminated site in Canada was analyzed for both homo- and hetero-PACs. Measured concentrations of Σ27HPAC (7.3 µg/g, dry weight) were significantly smaller (p<0.05) than Σ16PAHs (80.9 µg/g, dry weight) and Σ30Alkylated-PAHs (14.2 µg/g, dry weight). These results suggest that the developed method is an effective and efficient approach for the targeted analysis of HPACs and their halogenated derivatives in sediment samples.


Asunto(s)
Hidrocarburos Policíclicos Aromáticos , Compuestos Policíclicos , Cromatografía de Gases y Espectrometría de Masas/métodos , Espectrometría de Masas , Hidrocarburos Policíclicos Aromáticos/análisis , Cromatografía de Gases
10.
Environ Toxicol Chem ; 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39092785

RESUMEN

Quantitative adverse outcome pathways (qAOPs) describe the response-response relationships that link the magnitude and/or duration of chemical interaction with a specific molecular target to the probability and/or severity of the resulting apical-level toxicity of regulatory relevance. The present study developed the first qAOP for latent toxicities showing that early life exposure adversely affects health at adulthood. Specifically, a qAOP for embryonic activation of the aryl hydrocarbon receptor 2 (AHR2) of fishes by polycyclic aromatic hydrocarbons (PAHs) leading to decreased fecundity of females at adulthood was developed by building on existing qAOPs for (1) activation of the AHR leading to early life mortality in birds and fishes, and (2) inhibition of cytochrome P450 aromatase activity leading to decreased fecundity in fishes. Using zebrafish (Danio rerio) as a model species and benzo[a]pyrene as a model PAH, three linked quantitative relationships were developed: (1) plasma estrogen in adult females as a function of embryonic exposure, (2) plasma vitellogenin in adult females as a function of plasma estrogen, and (3) fecundity of adult females as a function of plasma vitellogenin. A fourth quantitative relationship was developed for early life mortality as a function of sensitivity to activation of the AHR2 in a standardized in vitro AHR transactivation assay to integrate toxic equivalence calculations that would allow prediction of effects of exposure to untested PAHs. The accuracy of the predictions from the resulting qAOP were evaluated using experimental data from zebrafish exposed as embryos to another PAH, benzo[k]fluoranthene. The qAOP developed in the present study demonstrates the potential of the AOP framework in enabling consideration of latent toxicities in quantitative ecological risk assessments and regulatory decision-making. Environ Toxicol Chem 2024;00:1-12. © 2024 SETAC.

11.
Breed Sci ; 63(2): 154-63, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23853509

RESUMEN

Making use of the markers linked closely to QTL for early-maturing traits for MAS (Marker-assisted selection) is an effective method for the simultaneous improvement of early maturity and other properties in cotton. In this study, two F2 populations and their F2:3 families were generated from the two upland cotton (Gossypium hirsutum L.) crosses, Baimian2 × TM-1 and Baimian2 × CIR12. QTL for early-maturing traits were analyzed using F2:3 families. A total of 54 QTL (31 suggestive and 23 significant) were detected. Fourteen significant QTL had the LOD scores not only > 3 but also exceeding permutation threshold. At least four common QTL, qBP-17 for bud period (BP), qGP-17a/qGP-17b (qGP-17) for growth period (GP), qYPBF-17a/qYPBF-17b (qYPBF-17) for yield percentage before frost (YPBF) and qHFFBN-17 for height of first fruiting branch node (HFFBN), were found in both populations. These common QTL should be reliable and could be used for MAS to facilitate early maturity. The common QTL, qBP-17, had a LOD score not only > 3 but also exceeding permutation threshold, explaining 12.6% of the phenotypic variation. This QTL should be considered preferentially in MAS. Early-maturing traits of cotton are primarily controlled by dominant and over-dominant effects.

12.
Zhonghua Yi Xue Za Zhi ; 93(45): 3573-6, 2013 Dec 03.
Artículo en Zh | MEDLINE | ID: mdl-24534304

RESUMEN

OBJECTIVE: To investigate the variations of macular thickness and peripapillary retinal nerve fiber layer (RNFL) thickness in myopic children. METHODS: A total of 96 eyes from 48 myopic children at department of Ophthalmology, Second Affiliated Hospital of Wenzhou Medical College from September 2010 to March 2012 were enrolled in this study and divided into three groups (low, moderate and high myopia group) according to the severity of myopia. Another 33 eyes from 19 emmetropic children were recruited as control group. The macular thickness and peripapillary RNFL thickness of the myopic children measured by optical coherence tomography were compared with that of the control group. RESULTS: The mean thickness of nasal, superior and inferior regions of outer-ring macular in the high myopia group were 276 µm, 294 µm, 285 µm respectively, which were significantly lower than that in the control group (P < 0.05). The mean thickness of superior of outer-ring macular in the low and moderate groups were 302 µm, 301 µm respectively, and the inferior of outer-ring ones were 288 µm, 283 µm respectively, which were significantly lower than that in the control group (P < 0.05). The temporal region of peripapillary RNFL thickness was significantly greater, and the other six regions of RNFL thicknesses were significantly lower in the high group than in the control group (P < 0.05). The central-1 mm, superior region of inner-ring, temporal and superior region of outer-ring macular thickness had positive correlations with spherical equivalent (SE) (P < 0.05). There was a negative correlation between the temporal peripapillary RNFL thickness and SE, while positive correlations were found between other regions of peripapillary RNFL thickness and SE (P < 0.05). CONCLUSIONS: The thicknesses of macular and peripapillary RNFL of myopic children have already redistributed before apparent changes of funds.


Asunto(s)
Mácula Lútea/diagnóstico por imagen , Miopía/diagnóstico por imagen , Retina/diagnóstico por imagen , Tomografía de Coherencia Óptica/métodos , Adolescente , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Humanos , Masculino , Disco Óptico , Radiografía
13.
Heliyon ; 9(7): e17240, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37415946

RESUMEN

Smart grid provides convenience for power generation, consumption and distribution. Authenticated key exchange (AKE) is a fundamental technique to protect data transmission from interception and tampering in smart grid. However, since the smart meters only have limited resources in computation and communication, most of the existing AKE schemes are inefficient for smart grid. First, many schemes have to use large security parameters to compensate the loose reduction in their security proofs. Second, most of these schemes require at least three-round of communication to negotiate a secret session key with explicit key confirmation. To alleviate these issues, we propose a novel two-round AKE scheme with tight security for smart grid. Our proposed scheme integrates Diffie-Hellman key exchange and a tightly secure digital signature, in which not only mutual authentication can be realized but also the communicating parties can confirm that session keys are negotiated between them explicitly. Compared with the existing AKE schemes, the overheads in both communication and computation are lighter in our proposed scheme, because fewer rounds of communication are required and smaller security parameters can be used to achieve the same security level. Therefore, our scheme contributes to a more practical solution for secure key establishment in smart grid.

14.
Chemosphere ; 335: 139059, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37268236

RESUMEN

Due to their relatively high trophic position and importance as a food source for many communities in the circumpolar north, seabird eggs are an important matrix for monitoring contaminant levels. In fact, many countries, including Canada, have established long-term seabird egg contaminant monitoring programs, with oil related compounds a contaminant of emerging concern for seabirds in several regions. Current approaches to measuring many contaminant burdens in seabird eggs are time-consuming and often require large volumes of solvent. Here we propose an alternative approach, based on the principle of microbead beating tissue extraction using custom designed stainless-steel extraction tubes and lids, to measure a suite of 75 polycyclic aromatic compounds (polycyclic aromatic hydrocarbons (PAHs), alkyl-PAHs, halogenated-PAHs and some heterocyclic compounds) comprising a wide-range of chemical properties. Our method was conducted in strict accordance with ISO/IEC 17025 guidelines for method validation. Accuracies for our analytes generally ranged from 70 - 120%, and intra and inter-day repeatability for most analytes were < 30%. Limits of detection/quantitation for the 75 target analytes were < 0.2/0.6 ng g-1. The level of contamination in our method blanks was significantly smaller in our stainless-steel tubes/lids relative to commercially available high-density plastic alternatives. Overall, our method meets our data quality objectives and results in a notable reduction in sample processing times relative to current approaches.


Asunto(s)
Hidrocarburos Policíclicos Aromáticos , Compuestos Policíclicos , Microesferas , Hidrocarburos Policíclicos Aromáticos/química , Solventes , Acero
15.
ACS Omega ; 8(39): 36543-36552, 2023 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-37810655

RESUMEN

Early screening and administration of DKD are beneficial for renal outcomes of type 2 diabetic patients. However, the current early diagnosis using the albuminuria/creatine ratio (ACR) contains limitations. This study aimed to compare serum lipidome variation between type 2 diabetes and early DKD patients with increased albuminuria through an untargeted lipidomics method to explore the potential lipid biomarkers for DKD identification. 92 type 2 diabetic patients were enrolled and divided into two groups: DM group (ACR < 3 mg/mmol, n = 49) and early DKD group (3 mg/mmol ≤ ACR < 30 mg/mmol, n = 43). Fasting serum was analyzed through an ultraperformance liquid mass spectrometry tandem chromatography system (LC-MS). Orthogonal partial least-squares discriminant analysis (OPLS-DA) and univariate and multivariate analysis were performed to filter differentially depressed lipids. Receiver operating characteristic (ROC) curves were used to estimate the diagnostic capability of potential lipid biomarkers. We found that serum phospholipids including phosphatidylserine (PS), sphingomyelin (SM), and phosphatidylcholine (PC) were significantly upregulated in the DKD group and were highly correlated with the ACR. In addition, a panel of two phospholipids including PS(27:0)-H and PS(30:2e)-H showed good performance to help clinical lipids in early DKD identification, which increased the area under the curve (AUC) from 0.568 to 0.954. The study exhibited the serum lipidome variation in early DKD patients, and the increased phospholipids might participate in the development of albuminuria. The panel of PS(27:0)-H and PS(30:2e)-H could be a potential biomarker for DKD diagnosis.

16.
Yi Chuan ; 34(6): 757-64, 2012 Jun.
Artículo en Zh | MEDLINE | ID: mdl-22698748

RESUMEN

"Pre-summer boll, summer boll and autumn boll" have long been regarded as an important index for prematurity and high-yield in cotton. In this study, the prematurity and high-yield cotton cultivar, Baimian 2, was used as the central parent to cross separately with the middle-late-matury lines TM-1 and CIR12, and then two populations of F2 and F2:3 family lines were obtained, which was used to construct two genetic linkage maps. These maps were comprised of 269 and 127 marker loci with the total length 1837.8 cM and 1244.3 cM, respectively. Results of QTL location showed that a total of 29 QTLs were detected in the two combinations, including 16 suggestive QTLs and 13 significant QTLs, of which 5 significant QTLs had higher LOD values that was not only greater than 3 but also greater than the threshold calculated by permutation test. The contribution rate of 16 QTLs explained 10.9%-44.5% of the phenotypic variations. Four common QTLs, qPSB-17 for pre-summer boll, qSB-17 (qSB-17a/17b) for summer boll, and qAB-17 and qAB-12/26 for autumn boll, were detected close to common markers of the same chromosome in the two combinations, which could be applied in marker-assisted selection. Moreover, the contribution rate of qSB-17 (qSB-17a/17b) for summer boll in the two combinations was greater than 10%, and that of qAB-17, qAB-12/26 for autumn boll in one combination were greater than 10%. These common QTLs with greater contribution rates should take into consideration firstly in marker-assisted selection.


Asunto(s)
Ligamiento Genético , Gossypium/genética , Sitios de Carácter Cuantitativo , Mapeo Cromosómico/métodos , Fenotipo
17.
Front Pharmacol ; 13: 940555, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35991874

RESUMEN

Anemarrhenae Rhizoma (AR) has multiple pharmacological activities to prevent and treat Alzheimer's disease (AD). However, the effect and its molecular mechanism are not elucidated clear. This study aims to evaluate AR's therapeutic effect and mechanism on AD model rats induced by D-galactose and AlCl3 with serum metabolomics. Behavior study, histopathological observations, and biochemical analyses were applied in the AD model assessment. Gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-QTOF/MS) were combined with multivariate statistical analysis to identify potential biomarkers of AD and evaluate the therapeutic effect of AR on AD from the perspective of metabolomics. A total of 49 biomarkers associated with the AD model were identified by metabolomics, and pathway analysis was performed to obtain the metabolic pathways closely related to the model. With the pre-treatment of AR, 32 metabolites in the serum of AD model rats were significantly affected by AR compared with the AD model group. The regulated metabolites affected by AR were involved in the pathway of arginine biosynthesis, arginine and proline metabolism, ether lipid metabolism, glutathione metabolism, primary bile acid biosynthesis, and steroid biosynthesis. These multi-platform metabolomics analyses were in accord with the results of behavior study, histopathological observations, and biochemical analyses. This study explored the therapeutic mechanism of AR based on multi-platform metabolomics analyses and provided a scientific basis for the application of AR in the prevention and treatment of AD.

18.
J Pharm Biomed Anal ; 210: 114576, 2022 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-34998074

RESUMEN

N-nitrosamines (NAs) are common toxic substances that have a strong correlation with many human diseases, such as liver damage and cancer. However, there is a lack of studies on methods involving the detection of NAs in biological samples, possibly owing to the interference of complex biological matrices and the influence of endogenous NAs. In this work, solid-phase extraction with mixed solid phases and adsorption sedimentation were used to successfully establish a gas chromatography-mass spectrometry (GC-MS) method for detecting eight NAs in rat faeces. Chromatographic separation of analytes was performed with Agilent VF-WAXms (30 m × 0.25 mm, 0.25 µm) GC columns. The LLOQs of eight NAs were set to the concentration of 0.5 ng/g and the obtained standard curves were linear, and correlation coefficients (r) were ≥ 0.99 for samples with concentration ranges of 0.5-500 ng/g. The inter and intra-assay precisions were< 15% for all analytes in the quality control samples, and the accuracies ranged from 88.67% to 108.33%. The extraction recoveries were above 78.56% for seven NAs, and a significant matrix effect was not observed. The application of this method revealed that the levels of NAS in the faeces of rats with colorectal cancer were higher than those of normal rats. Additionally, the effect of a high nitrite diet on NAs in faeces was analysed; the results confirmed that a high nitrite diet might contribute to an abnormal increase in NAs. Our work provides an analytical method for further in vivo study of NAs. Furthermore, a pilot study on the relationship between NAs and colorectal cancer was completed.


Asunto(s)
Neoplasias Colorrectales , Nitrosaminas , Animales , Heces/química , Cromatografía de Gases y Espectrometría de Masas , Nitrosaminas/análisis , Proyectos Piloto , Ratas , Espectrometría de Masas en Tándem
19.
Environ Toxicol Chem ; 41(8): 1993-2002, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35694968

RESUMEN

Polycyclic aromatic hydrocarbons (PAHs) are structurally diverse organic chemicals that can have adverse effects on the health of fishes through activation of aryl hydrocarbon receptor 2 (AhR2). They are ubiquitous in the environment, but alkyl PAHs are more abundant in some environmental matrices. However, relatively little is known regarding the effects of alkylation on the toxicity of PAHs to fishes in vivo and how this relates to potency for activation of AhR2 in vitro. Therefore, the objectives of the present study were to determine the toxicity of benz[a]anthracene and three alkylated homologs representing various alkylation positions to early life stages of zebrafish (Danio rerio) and to assess the potency of each for activation of the zebrafish AhR2 in a standardized in vitro AhR transactivation assay. Exposure of embryos to each of the PAHs caused a dose-dependent increase in mortality and malformations characteristic of AhR2 activation. Each alkyl homolog had in vivo toxicities and in vitro AhR2 activation potencies different from those of the parent PAH in a position-dependent manner. However, there was no statistically significant linear relationship between responses measured in these assays. The results suggest a need for further investigation into the effect of alkylation on the toxicity of PAHs to fishes and greater consideration of the contribution of alkylated homologs in ecological risk assessments. Environ Toxicol Chem 2022;41:1993-2002. © 2022 SETAC.


Asunto(s)
Hidrocarburos Policíclicos Aromáticos , Pez Cebra , Alquilación , Animales , Antracenos/metabolismo , Embrión no Mamífero , Hidrocarburos Policíclicos Aromáticos/metabolismo , Hidrocarburos Policíclicos Aromáticos/toxicidad , Receptores de Hidrocarburo de Aril/genética , Receptores de Hidrocarburo de Aril/metabolismo , Activación Transcripcional , Pez Cebra/metabolismo
20.
Aquat Toxicol ; 232: 105766, 2021 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-33578324

RESUMEN

Spills of diluted bitumen (dilbit) from pipelines pose a risk to the health of aquatic organisms, including fish, and with expected increases in production and transportation of dilbit, these risks could increase. To date, the majority of studies have investigated effects of fresh dilbit on aquatic organisms, but little is known about effects of weathered sediment-bound dilbit, including mechanisms of toxicity. The goal of this study was to use 1H NMR based metabolomics to identify altered metabolites and pathways in early life-stages of zebrafish (Danio rerio) exposed to a sediment derived water-soluble fraction of dilbit (SDWSF) to better understand mechanisms of adverse effects. Zebrafish embryos exposed to the SDWSF until 120 h post-fertilization exhibited increased prevalence of pericardial edema, yolk sac edema, and swim bladder malformations that are typical of exposure to fresh dilbit. Concentrations of nine metabolites (alanine, glutamine, lysine, threonine, tyrosine, betaine, taurine, inosine, and glycerol) were significantly altered in embryos exposed to SDWSF. Pathway topology analysis revealed four potentially impacted pathways: 1) phenylalanine, tyrosine, and tryptophan biosynthesis, 2) taurine and hypotaurine metabolism, 3) alanine, aspartate, and glutamate metabolism, and 4) glycine, serine, and threonine metabolism. Altered metabolites were linked to several biological process, that when perturbed could be key events in mechanisms of developmental effects observed in embryos. Future studies should further investigate the role of perturbations to these metabolites and pathways to determine the specific role they might play in adverse effects of exposure to dilbit.

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