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BACKGROUND: To determine whether there is a correlation between stiffness measured by strain elastography and the severity of dysmenorrhea and to determine the value of elastography in evaluating severe dysmenorrhea in patients with adenomyosis. METHODS: The correlation between tissue stiffness and dysmenorrhea was analyzed by performing elastography on premenopausal women diagnosed with adenomyosis. Expression levels of transforming growth factor-ß (TGF-ß), α-smooth muscle actin (α-SMA), and protein gene product 9.5 (PGP9.5) were detected by immunohistochemistry; the correlation of TGF-ß and α-SMA levels with the tissue stiffness and the degree of fibrosis was further analyzed. Also, the relationship of the PGP9.5 expression level with the tissue stiffness and degree of dysmenorrhea was determined. RESULTS: The degree of dysmenorrhea was significantly positively correlated with lesion stiffness in patients with adenomyosis but not with the uterine or lesion volume. The cutoff for the strain ratio was > 1.36 between the adenomyosis and control groups, with an area under the curve (AUC) of 0.987. For severe dysmenorrhea, the cutoff for the strain ratio was > 1.65 in patients with adenomyosis, with an AUC of 0.849. TGF-ß, α-SMA, and PGP9.5 expression levels were higher in adenomyotic lesions than in the endometrium of the adenomyosis and control groups. Both TGF-ß and α-SMA levels were positively correlated with the tissue stiffness and degree of fibrosis. Additionally, the expression level of PGP9.5 showed a positive correlation with the tissue stiffness and degree of dysmenorrhea. CONCLUSIONS: Elastography can be used to evaluate the degree of dysmenorrhea; the greater the tissue stiffness, the greater the degree of dysmenorrhea. In addition, elastography performed well in the diagnosis of adenomyosis and the evaluation of severe dysmenorrhea in patients with adenomyosis.
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Adenomiosis , Diagnóstico por Imagen de Elasticidad , Humanos , Femenino , Adenomiosis/complicaciones , Adenomiosis/diagnóstico por imagen , Adenomiosis/metabolismo , Dismenorrea/diagnóstico por imagen , Dismenorrea/metabolismo , Factor de Crecimiento Transformador beta , FibrosisRESUMEN
The aim of this study was to probe an unexpected relationship between the ice nucleation temperature (TIN), process efficiency and product attributes in a controlled ice nucleation (CIN) lyophilization process. An amorphous product was lyophilized with (CIN-5 °C, CIN-7 °C or CIN-10 °C) or without (NOCIN) control of ice nucleation. Process parameters and product attributes were monitored and compared using a series of advanced in-line and off-line process analytical technology (PAT) tools. Unexpectedly, an indirect relationship was observed between TIN and primary drying efficiency for the CIN processes. Further, the CIN-5 °C process was associated with higher product resistance to mass flow than corresponding CIN-7 °C and CIN-10 °C processes. Surprisingly, the air voids in some NOCIN products were larger than CIN-5 °C products but comparable to CIN-7 °C. Heat flux analysis revealed an indirect relationship between TIN and the minimum hold time required to complete solidification. The heat flux analysis also revealed all products underwent complete solidification prior to primary drying. The order of homogeneity in water activity of the products was CIN-5 °C ≥NOCIN>CIN-7 °C. The higher homogeneity in water activity of CIN-5 °C than corresponding CIN-7 °C processes indicated that the lower process efficiency of CIN-5 °C could not be attributed to unsuccessful induction of ice nucleation during CIN-5 °C. High resolution micro-CT imaging and Artificial Intelligence Image analysis revealed cake wall deformation in CIN-7 °C and NOCIN products but not in CIN-5 °C. In addition, NOCIN products had bimodal distribution in air voids with median size range of 4-5 µm and 151.9-309 µm, respectively, hence the lower process efficiency of NOCIN despite the higher D90. Thus, the observed relationship between TIN and process efficiency may be attributed to microstructural changes post freezing. This hypothesis was corroborated by visible macroscopic cake collapse in NOCIN products but not in CIN products after lyophilization at a higher shelf temperature. In conclusion, the advantages of controlling the ice nucleation temperature of a lyophilization process may only be attained through a robust process design that takes into consideration the primary and secondary drying process parameters. Further, combined use of advanced in-line and off-line PAT tools for process and product characterization may hasten the at scale adoption of advance techniques such as CIN.
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Hielo , Análisis de Causa Raíz , Temperatura , Inteligencia Artificial , Agua , Liofilización/métodosRESUMEN
CONTEXT: High-energy density materials (HEDMs) have emerged as a research focus due to their advantageous ultra-high detonation performance and better sensitivity. The primary aim of this study revolves around crafting HEDMs that strike a delicate balance between exceptional performance and minimal sensitivity. Density functional theory (DFT) was utilized to evaluate the geometric structures, energies, densities, energy properties, and sensitivities of 39 designed derivatives. The theoretical density (ρ) and heat of formation (HOF) were used to estimate the detonation velocity (D) and pressure (P) of the title compounds. Our study shows that the introduction of fluorine-containing substituents or fluorine-free substituents into the CHOFN backbone or the CHON backbone can significantly enhance the detonation performance of derivatives. Derivative B1 exhibits the better overall performance, including superior density, detonation performance, and sensitivity (P = 58.89 GPa, D = 8.02 km/s, ρ = 1.93 g/cm3, and characteristic height H50 = 34.6 cm). Our molecular design strategy contributes to the development of more novel HEDMs with excellent detonation performance and stability. It also marks a significant step towards a material engineering era guided by theory-based rational design. METHODS: GaussView 6.0 was used for construction of molecular system coordinates, and Gaussian 16 was used to obtain optimal structures, energies, and volumes of all compounds at the B3LYP/6-31+G(d,p) level of theory. It was characterized to be the local energy minimum on the potential energy surface without imaginary frequencies at the same theory level. Molecular weight, isosurface area, and overall variance were obtained using the Multiwfn 3.3. The detonation properties of the materials were analyzed using the C-J thermodynamic detonation theory. Our broad analysis facilitated an extensive assessment of these properties.
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DNA nanostructures are well-established vectors for packaging diversified payloads for targeted cellular delivery. Here, DNA origami rectangular sheets were combined with Herpes Simplex Virus 1 (HSV1) capsids to demonstrate surface coverage of the particle via electrostatic interactions. The optimized origami:HSV1 molar ratios led to characteristic packaging geometries ranging from dispersed "HSV1 pockets" to agglomerated "HSV1 sleeves". "Pockets" were disguised from cells in HeLa and B16F10 cells and were 44.2% less infective than naked HSV1 particles. However, the pockets were 117% more infective than naked HSV1 particles when the origami sheets were coated with folic acid. We observed infectivity from naked origami, but they are 99.1% less infective with respect to HSV1 and 99.6% less infective with respect to the pocket complexes. This work suggests that DNA origami can selectively modulate virus infectivity.
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Herpes Simple , Herpesvirus Humano 1 , Humanos , Virulencia , Cápside , ADN/genética , Proteínas de la Cápside/químicaRESUMEN
BACKGROUND: To investigate the prenatal ultrasonographic features and case characteristics of the congenital intrahepatic portosystemic venous shunt (IHPSS) diagnosed during the foetal period and analyse its prognosis. METHODS: We conducted a retrospective cohort study of patients diagnosed with IHPSS between 2016 and 2021. IHPSS was defined as an abnormal connection between the foetal intrahepatic portal and the hepatic veins. RESULTS: In this study, 19 foetuses were identified, including 12 cases of single shunt and 7 cases of multiple shunts, with a gestational age of 33.8 ± 4.5 (range 25-40) weeks at diagnosis. In the single-shunt group, the origin position of the shunts was all from the left branch of the portal vein (LPV), whereas in the multiple-shunt group, the origin position of the shunts was from the LPV in six cases. Common concomitant intrauterine abnormalities of IHPSS include foetal growth restriction (47.4%) and foetal cardiac enlargement (21.1%). The postnatal manifestations of IHPSS include biochemical abnormalities (increased gamma-glutamyl transferase and bilirubin levels), neonatal hypoglycaemia, neonatal hyperammonaemia, pulmonary hypertension, multiple intrahepatic hyperechoic nodules, and cutaneous haemangiomas. Spontaneous closure of shunts occurred in ten cases, and the mean time to shunt closure was 8.1 months (1-28 months). CONCLUSIONS: Most IHPSS found during the foetal period is located in the left branch of the portal vein, and the gestational age at diagnosis is usually in the late second or third trimester. Spontaneous closure of shunts can occur in most live births, and the prognosis is good.
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Development of heart failure (HF) after myocardial infarction (MI) is responsible for premature death. Complex cellular and molecular mechanisms are involved in this process. A number of studies have linked the epitranscriptomic RNA modification N6-methyladenosine (m6A) with HF, but it remains unknown how m6A affects the risk of developing HF after MI. We addressed the regulation of m6A and its demethylase fat mass and obesity-associated (FTO) after MI and their association with HF. Using liquid chromatography coupled to mass spectrometry, we observed an increase of m6A content in the infarcted area of rat hearts subjected to coronary ligation and a decrease in blood. FTO expression measured by quantitative PCR was downregulated in the infarcted hearts. In whole blood samples collected at the time of reperfusion in MI patients, m6A content was lower in patients who developed HF as attested by a 4-month ejection fraction (EF) of ≤40% as compared to patients who did not develop HF (EF > 50%). M6A content was higher in females. These results show that m6A measured in blood is associated with HF development after MI and motivate further investigation of the potential role of m6A as a novel epitranscriptomics biomarker and therapeutic target of HF.
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Insuficiencia Cardíaca , Infarto del Miocardio , Adenosina/análogos & derivados , Adenosina/metabolismo , Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato/genética , Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato/metabolismo , Femenino , Humanos , ARN Mensajero/genética , Función Ventricular IzquierdaRESUMEN
BACKGROUND: Ultrasound is a critical non-invasive test for preoperative diagnosis of ovarian cancer. Deep learning is making advances in image-recognition tasks; therefore, we aimed to develop a deep convolutional neural network (DCNN) model that automates evaluation of ultrasound images and to facilitate a more accurate diagnosis of ovarian cancer than existing methods. METHODS: In this retrospective, multicentre, diagnostic study, we collected pelvic ultrasound images from ten hospitals across China between September 2003, and May 2019. We included consecutive adult patients (aged ≥18 years) with adnexal lesions in ultrasonography and healthy controls and excluded duplicated cases and patients without adnexa or pathological diagnosis. For DCNN model development, patients were assigned to the training dataset (34â488 images of 3755 patients with ovarian cancer, 541â442 images of 101â777 controls). For model validation, patients were assigned to the internal validation dataset (3031 images of 266 patients with ovarian cancer, 5385 images of 602 with benign adnexal lesions), external validation datasets 1 (486 images of 67 with ovarian cancer, 933 images of 268 with benign adnexal lesions), and 2 (1253 images of 166 with ovarian cancer, 5257 images of 723 benign adnexal lesions). Using these datasets, we assessed the diagnostic value of DCNN, compared DCNN with 35 radiologists, and explored whether DCNN could augment the diagnostic accuracy of six radiologists. Pathological diagnosis was the reference standard. FINDINGS: For DCNN to detect ovarian cancer, AUC was 0·911 (95% CI 0·886-0·936) in the internal dataset, 0·870 (95% CI 0·822-0·918) in external validation dataset 1, and 0·831 (95% CI 0·793-0·869) in external validation dataset 2. The DCNN model was more accurate than radiologists at detecting ovarian cancer in the internal dataset (88·8% vs 85·7%) and external validation dataset 1 (86·9% vs 81·1%). Accuracy and sensitivity of diagnosis increased more after DCNN-assisted diagnosis than assessment by radiologists alone (87·6% [85·0-90·2] vs 78·3% [72·1-84·5], p<0·0001; 82·7% [78·5-86·9] vs 70·4% [59·1-81·7], p<0·0001). The average accuracy of DCNN-assisted evaluations for six radiologists reached 0·876 and were significantly augmented when they were DCNN-assisted (p<0·05). INTERPRETATION: The performance of DCNN-enabled ultrasound exceeded the average diagnostic level of radiologists matched the level of expert ultrasound image readers, and augmented radiologists' accuracy. However, these observations warrant further investigations in prospective studies or randomised clinical trials. FUNDING: National Key Basic Research Program of China, National Sci-Tech Support Projects, and National Natural Science Foundation of China.
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Aprendizaje Profundo , Neoplasias Ováricas , Adolescente , Adulto , China , Femenino , Humanos , Neoplasias Ováricas/diagnóstico por imagen , Estudios Prospectivos , Estudios Retrospectivos , Ultrasonografía/métodosRESUMEN
A disintegrin-like and metalloprotease domain with thrombospondin type 1 motifs (ADAMTS)8 is a secreted protease, which was recently implicated in pathogenesis of pulmonary arterial hypertension (PAH). However, the substrate repertoire of ADAMTS8 and regulation of its activity are incompletely understood. Although considered a proteoglycanase because of high sequence similarity and close phylogenetic relationship to the proteoglycan-degrading proteases ADAMTS1, 4, 5, and 15, as well as tight genetic linkage with ADAMTS15 on human chromosome 11, its aggrecanase activity was reportedly weak. Several post-translational factors are known to regulate ADAMTS proteases such as autolysis, inhibition by endogenous inhibitors, and receptor-mediated endocytosis, but their impacts on ADAMTS8 are unknown. Here, we show that ADAMTS8 undergoes autolysis at six different sites within its spacer domain. We also found that in contrast to ADAMTS4 and 5, ADAMTS8 levels were not regulated through low-density lipoprotein receptor-related protein 1 (LRP1)-mediated endocytosis. Additionally, ADAMTS8 lacked significant activity against the proteoglycans aggrecan, versican, and biglycan. Instead, we found that ADAMTS8 cleaved osteopontin, a phosphoprotein whose expression is upregulated in PAH. Multiple ADAMTS8 cleavage sites were identified using liquid chromatography-tandem mass spectrometry. Osteopontin cleavage by ADAMTS8 was efficiently inhibited by TIMP-3, an endogenous inhibitor of ADAMTS1, 4, and 5, as well as by TIMP-2, which has no previously reported inhibitory activity against other ADAMTS proteases. These differences in post-translational regulation and substrate repertoire differentiate ADAMTS8 from other family members and may help to elucidate its role in PAH.
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Proteínas ADAMTS/metabolismo , Procesamiento Proteico-Postraduccional , Proteolisis , Hipertensión Arterial Pulmonar/enzimología , Proteínas ADAMTS/genética , Células HEK293 , Humanos , Osteopontina/genética , Osteopontina/metabolismo , Proteoglicanos/genética , Proteoglicanos/metabolismo , Hipertensión Arterial Pulmonar/genética , Inhibidor Tisular de Metaloproteinasa-3/genética , Inhibidor Tisular de Metaloproteinasa-3/metabolismoRESUMEN
OBJECTIVES: A classification termed umbilical-portal-systemic venous shunt (UPSVS) for an abnormal umbilical vein (UV), portal vein (PV), and ductus venosus (DV) was proposed recently. According to this classification, there are 3 types of UPSVSs: types I, II, and III. Trisomy 21 associated with UV-PV-DV anomalies has been described, but the incidence of trisomy 21 in UPSVS cases, the relationship between UPSVS types and trisomy 21, and the pregnancy outcome are poorly documented. This study aimed to address these issues. METHODS: All UPSVS cases diagnosed at our department from 2016 to 2019 were retrospectively studied. The English literature describing UV-PV-DV anomalies and trisomy 21 from 2000 to 2019 was searched, and the retrieved cases were analyzed. RESULTS: Four of 20 UPSVS cases identified by us also had trisomy 21, with 2 type I and 2 type II UPSVSs. Ultrasound markers of Down syndrome were observed in all 4 cases that underwent termination of pregnancy (TOP). The literature search retrieved 12 reports including 279 patients, with 29 also having trisomy 21, giving a pooled trisomy 21 incidence rate of 10.4%. Of the 29 cases, 16 had type I, and 9 had type II, whereas UPSVS types in 4 were undeterminable, and 22 cases underwent TOP. CONCLUSIONS: There is a high incidence of trisomy 21 in UPSVS cases. Trisomy 21 is associated with a type I or II UPSVS. Most cases with the combined defect underwent TOP. These findings may be used to direct prenatal counseling and management of the combined condition.
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Síndrome de Down , Síndrome de Down/complicaciones , Síndrome de Down/diagnóstico por imagen , Femenino , Humanos , Vena Porta/diagnóstico por imagen , Embarazo , Estudios Retrospectivos , Trisomía , Ultrasonografía Prenatal , Venas Umbilicales/diagnóstico por imagenRESUMEN
Beside its genomic properties, DNA is also recognized as a novel material in the field of nanoengineering. The specific bonding of base pairs can be used to direct the assembly of highly structured materials with specific nanoscale features such as periodic 2D arrays, 3D nanostructures, assembly of nanomaterials, and DNA nanomachines. In recent years, a variety of DNA nanomachines are developed because of their many potential applications in biosensing, diagnostics, and therapeutic applications. In this review, the fuel-powered motors and secondary structure motors, whose working mechanisms are inspired or derived from natural phenomena and nanomachines, are discussed. The combination of DNA motors with other platforms is then discussed. In each section of these motors, their mechanisms and their usage in the biomedical field are described. Finally, it is believed that these DNA-based nanomachines and hybrid motifs will become an integral point-of-care diagnostics and smart, site-specific therapeutic delivery.
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Técnicas Biosensibles/métodos , ADN , Técnicas de Diagnóstico Molecular/métodos , Nanoestructuras , Sistemas de Atención de Punto , Animales , Técnicas Biosensibles/tendencias , ADN/química , ADN/uso terapéutico , Humanos , Técnicas de Diagnóstico Molecular/tendencias , Nanoestructuras/química , Nanoestructuras/uso terapéuticoRESUMEN
Metabolomic markers associated with incident central adiposity gain were investigated in young adults. In a 9-mo prospective study of university freshmen (n = 264). Blood samples and anthropometry measurements were collected in the first 3 d on campus and at the end of the year. Plasma from individuals was pooled by phenotype [incident central adiposity, stable adiposity, baseline hemoglobin A1c (HbA1c) > 5.05%, HbA1c < 4.92%] and assayed using GC-MS, chromatograms were analyzed using MetaboliteDetector software, and normalized metabolite levels were compared using Welch's t test. Assays were repeated using freshly prepared pools, and statistically significant metabolites were quantified in a targeted GC-MS approach. Isotope tracer studies were performed to determine if the potential marker was an endogenous human metabolite in men and in whole blood. Participants with incident central adiposity gain had statistically significantly higher blood erythritol [P < 0.001, false discovery rate (FDR) = 0.0435], and the targeted assay revealed 15-fold [95% confidence interval (CI): 13.27, 16.25] higher blood erythritol compared with participants with stable adiposity. Participants with baseline HbA1c > 5.05% had 21-fold (95% CI: 19.84, 21.41) higher blood erythritol compared with participants with lower HbA1c (P < 0.001, FDR = 0.00016). Erythritol was shown to be synthesized endogenously from glucose via the pentose-phosphate pathway (PPP) in stable isotope-assisted ex vivo blood incubation experiments and through in vivo conversion of erythritol to erythronate in stable isotope-assisted dried blood spot experiments. Therefore, endogenous production of erythritol from glucose may contribute to the association between erythritol and obesity observed in young adults.
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Adiposidad/fisiología , Eritritol/sangre , Eritritol/metabolismo , Vía de Pentosa Fosfato/fisiología , Aumento de Peso/fisiología , Adolescente , Adulto , Femenino , Cromatografía de Gases y Espectrometría de Masas , Glucosa/metabolismo , Hemoglobina Glucada/metabolismo , Humanos , Masculino , Metabolómica , Obesidad/patología , Estudios Prospectivos , Estudiantes , Universidades , Adulto JovenRESUMEN
Mutations in succinate dehydrogenase (SDH) are associated with tumor development and neurodegenerative diseases. Only in tumors, loss of SDH activity is accompanied with the loss of complex I activity. Yet, it remains unknown whether the metabolic phenotype of SDH mutant tumors is driven by loss of complex I function, and whether this contributes to the peculiarity of tumor development versus neurodegeneration. We addressed this question by decoupling loss of SDH and complex I activity in cancer cells and neurons. We found that sole loss of SDH activity was not sufficient to recapitulate the metabolic phenotype of SDH mutant tumors, because it failed to decrease mitochondrial respiration and to activate reductive glutamine metabolism. These metabolic phenotypes were only induced upon the additional loss of complex I activity. Thus, we show that complex I function defines the metabolic differences between SDH mutation associated tumors and neurodegenerative diseases, which could open novel therapeutic options against both diseases.
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Complejo I de Transporte de Electrón , Mutación , Proteínas de Neoplasias , Neoplasias , Succinato Deshidrogenasa , Línea Celular Tumoral , Complejo I de Transporte de Electrón/genética , Complejo I de Transporte de Electrón/metabolismo , Humanos , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neoplasias/enzimología , Neoplasias/genética , Neoplasias/patología , Neuronas/enzimología , Neuronas/patología , Succinato Deshidrogenasa/genética , Succinato Deshidrogenasa/metabolismoRESUMEN
BACKGROUND: Metabolism gained increasing interest for the understanding of diseases and to pinpoint therapeutic intervention points. However, classical metabolomics techniques only provide a very static view on metabolism. Metabolic flux analysis methods, on the other hand, are highly targeted and require detailed knowledge on metabolism beforehand. RESULTS: We present a novel workflow to analyze non-targeted metabolome-wide stable isotope labeling data to detect metabolic flux changes in a non-targeted manner. Furthermore, we show how similarity-analysis of isotopic enrichment patterns can be used for pathway contextualization of unidentified compounds. We illustrate our approach with the analysis of changes in cellular metabolism of human adenocarcinoma cells in response to decreased oxygen availability. Starting without a priori knowledge, we detect metabolic flux changes, leading to an increased glutamine contribution to acetyl-CoA production, reveal biosynthesis of N-acetylaspartate by N-acetyltransferase 8-like (NAT8L) in lung cancer cells and show that NAT8L silencing inhibits proliferation of A549, JHH-4, PH5CH8, and BEAS-2B cells. CONCLUSIONS: Differential stable isotope labeling analysis provides qualitative metabolic flux information in a non-targeted manner. Furthermore, similarity analysis of enrichment patterns provides information on metabolically closely related compounds. N-acetylaspartate and NAT8L are important players in cancer cell metabolism, a context in which they have not received much attention yet.
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BACKGROUND: Hypoxia and inflammation have been identified as hallmarks of cancer. A majority of hepatocellular carcinomas are preceded by hepatitis B- or C-related chronic infections suggesting that liver cancer development is promoted by an inflammatory microenvironment. The inflammatory cytokine oncostatin M (OSM) was shown to induce the expression of hypoxia-inducible factor-1 α (HIF-1 α) under normoxic conditions in hepatocytes and hepatoma cells. HIF-1 α is known to orchestrate the expression of numerous genes, many of which code for metabolic enzymes that play key roles in the adaptation of cellular metabolism to low oxygen tension. RESULTS: Here, we show that OSM-induced upregulation of HIF-1 α reprograms cellular metabolism in three clones of the human hepatocyte cell line PH5CH (PH5CH1, PH5CH7, and PH5CH8) towards a hypoxia-like metabolic phenotype but has no significant effect on cellular metabolism of HepG2 and JHH-4 hepatoma cells. Although we observed only minor changes in glucose uptake and lactate secretion in PH5CH8 upon OSM treatment, we identified more pronounced changes in intracellular fluxes based on stable isotope labeling experiments. In particular, glucose oxidation in the tricarboxylic acid (TCA) cycle is reduced through pyruvate dehydrogenase kinase 1 (PDK1)-mediated inhibition of the pyruvate dehydrogenase complex, thereby reducing the oxidative TCA cycle flux. As a result of the impaired mitochondrial glucose and glutamine oxidation, the reductive isocitrate dehydrogenase flux was increased. CONCLUSIONS: We provide evidence that connects the inflammatory mediator OSM to a hypoxia-like metabolic phenotype. In the human hepatocyte cell line PH5CH, OSM-mediated upregulation of HIF-1 α and PDK1 can induce hypoxia-like metabolic changes, although to a lesser extent than hypoxia itself. Since PDK1 is overexpressed in several cancers, it might provide a causal link between chronic inflammation and malignant cellular transformation.
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The accurate determination of mass isotopomer distributions (MID) is of great significance for stable isotope-labeling experiments. Most commonly, MIDs are derived from gas chromatography/electron ionization mass spectrometry (GC/EI-MS) measurements. The analysis of fragment ions formed during EI, which contain only specific parts of the original molecule can provide valuable information on the positional distribution of the label. The chemical formula of a fragment ion is usually applied to derive the correction matrix for accurate MID calculation. Hence, the correct assignment of chemical formulas to fragment ions is of crucial importance for correct MIDs. Moreover, the positional distribution of stable isotopes within a fragment ion is of high interest for stable isotope-assisted metabolomics techniques. For example, (13)C-metabolic flux analyses ((13)C-MFA) are dependent on the exact knowledge of the number and position of retained carbon atoms of the unfragmented molecule. Fragment ions containing different carbon atoms are of special interest, since they can carry different flux information. However, the process of mass spectral fragmentation is complex, and identifying the substructures and chemical formulas for these fragment ions is nontrivial. For that reason, we developed an algorithm, based on a systematic bond cleavage, to determine chemical formulas and retained atoms for EI derived fragment ions. Here, we present the fragment formula calculator (FFC) algorithm that can calculate chemical formulas for fragment ions where the chemical bonding (e.g., Lewis structures) of the intact molecule is known. The proposed algorithm is able to cope with general molecular rearrangement reactions occurring during EI in GC/MS measurements. The FFC algorithm is able to integrate stable isotope labeling experiments into the analysis and can automatically exclude candidate formulas that do not fit the observed labeling patterns.1 We applied the FFC algorithm to create a fragment ion repository that contains the chemical formulas and retained carbon atoms of a wide range of trimethylsilyl and tert-butyldimethylsilyl derivatized compounds. In total, we report the chemical formulas and backbone carbon compositions for 160 fragment ions of 43 alkylsilyl-derivatives of primary metabolites. Finally, we implemented the FFC algorithm in an easy-to-use graphical user interface and made it publicly available at http://www.ffc.lu .
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Algoritmos , Cromatografía de Gases y Espectrometría de Masas/métodos , Marcaje Isotópico , Espectrometría de Masas/métodos , Peso MolecularRESUMEN
In the present study, the acute and developmental toxicities of imidazolium ionic liquids (ILs) with different alkyl chain lengths, as well as the antioxidant response and lipid peroxidation levels were evaluated in the snail, Physa acuta. Longer alkyl chains corresponded to increased IL toxicity in snails. Long-term IL exposure at lower concentrations inhibited snail growth and reproduction. We also found that IL inhibited the activities of superoxide dismutase (SOD) and glutathione S-transferase (GST), promoted the activity of catalase (CAT), and increased the glutathione content. However, SOD, GST, and CAT activities returned to control levels after 96 h of recovery. In addition, malondialdehyde levels were increased in treatment groups compared with the control and did not return to control levels even after a recovery period, indicating that ILs induced lipid peroxidation in snail viscera. These results suggest that oxidative stress and lipid peroxidation may be involved in the mechanism of toxicity for ILs.
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Imidazoles/toxicidad , Líquidos Iónicos/toxicidad , Caracoles/efectos de los fármacos , Caracoles/fisiología , Estrés Fisiológico/efectos de los fármacos , Pruebas de Toxicidad Aguda , Envejecimiento/efectos de los fármacos , Animales , Antioxidantes , Catalasa/metabolismo , Glutatión/metabolismo , Glutatión Transferasa/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Malondialdehído/metabolismo , Caracoles/enzimología , Superóxido Dismutasa/metabolismo , Vísceras/efectos de los fármacos , Vísceras/enzimologíaRESUMEN
The embryonic and postembryonic developmental toxicity of imidazolium-based ionic liquids (ILs) to the snail Physa acuta was evaluated in this study. The results of embryonic toxicity tests showed that lower concentrations of 1-octyl-3-methylimidazolium bromide ([C8 mim]Br) (1.5 and 2.1 mg/L) inhibited the hatching rate of snail embryos, and partial snails hatched normally and died, while all of the treated embryos died when the exposure concentration was higher than 4.16 mg/L, at which IL caused the deformation, death, and decay of snail embryos. Statistical analyses revealed obvious differences in the hatching rates between three developmental stages in the 2.1 and 2.94 mg/L groups, indicating that the veliger stage is more sensitive to [C8 mim]Br exposure than the blastula and gastrula stages. Furthermore, the 96 h LC50 values of [C8 mim]Br on the tested snails at three developmental stages (juvenile, subadult, and adult) were 70.83 ± 2.99, 97.59 ± 4.05, and 109.3 ± 2.22 mg/L, respectively, indicating that young snails were more sensitive to [C8 mim]Br toxicity than adults. In addition, the 96 h LC50 values of ILs with different alkyl chain lengths, that is, [C12 mim], [C10 mim], [C8 mim], and [C6 mim], in adult snails were 1.35 ± 0.24, 8.96 ± 5.66, 109.3 ± 4, and 359.6 ± 11.6 mg/L, respectively, suggesting that longer alkyl chains can increase the toxicity of imidazolium ILs on snails.
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Boratos/toxicidad , Imidazoles/toxicidad , Líquidos Iónicos/toxicidad , Caracoles/efectos de los fármacos , Animales , Embrión no Mamífero/efectos de los fármacos , Caracoles/embriología , Pruebas de Toxicidad AgudaRESUMEN
The aim of this study was to determine the effects of short-term resistance training combined with systemic hypoxia on muscular performance and body composition. Eighteen resistance-untrained men (21.3 ± 2.0 years, 172.7 ± 5.5 cm, 67.3 ± 9.7 kg) were matched and assigned to 2 experimental groups: performing 6 weeks of squat exercise training under normobaric hypoxia (H, FiO2 = 15%) or normoxia (N). In both groups, subjects performed 3 weekly sessions (a total of 18 sessions) of 3 sets of back squat at 10-repetition maximum with 2 minutes of rest between sets. Dynamic, isometric, and isokinetic leg strength and body composition were measured under normoxia before and after resistance training. Squat 1 repetition maximum (1RM) improved significantly (p ≤ 0.05) after resistance training in both H and N groups (88.9 ± 16.9 to 109.4 ± 17.0 kg and 90.0 ± 12.2 to 105.6 ± 13.3 kg, respectively). However, there were no changes in maximal isometric and isokinetic leg strength, lean body mass, and fat mass after the resistance training in both groups. In addition, no significant differences were observed between H and N groups in squat 1RM, maximal isometric and isokinetic leg strength, and body composition. The major findings of this study suggest that short-term resistance training performed under normobaric hypoxia has no additive beneficial effect on muscular performance and body composition. In practical terms, our data suggest that the use of systemic hypoxia during short-term resistance training is not a viable method to further enhance muscular performance and body composition in previously resistance-untrained men.
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Composición Corporal , Hipoxia/fisiopatología , Fuerza Muscular/fisiología , Resistencia Física , Entrenamiento de Fuerza/métodos , Adaptación Fisiológica , Adolescente , Rendimiento Atlético , Estudios Transversales , Humanos , Masculino , Músculo Esquelético/fisiología , Consumo de Oxígeno/fisiología , Valores de Referencia , Adulto JovenRESUMEN
Acute toxicity of 1-methyl-3-octylimidazolium bromide ([C(8)mim]Br) to goldfish at different developmental stages and responses of the antioxidant system in adult goldfish were evaluated in the present study. The results indicate that post-embryonic developmental toxicity of [C(8)mim]Br on goldfish is developmental-stage dependent. The juvenile and larva goldfish are more sensitive to [C(8)mim]Br-toxicity than the adult fish. Histological observations in adult goldfish reveal that acute [C(8)mim]Br exposure damages the hepatopancreas, intestines, and kidneys, indicating that these are possible target organs of [C(8)mim]Br toxicity in goldfish. Subsequent biochemical assays in adult goldfish show that [C(8)mim]Br also induces changes in the activities of the superoxide dismutase, catalase, glutathione peroxidase, and glutathione content of fish hepatopancreas. These results suggest that [C(8)mim]Br exposure may induce oxidant stress and lipid peroxidation in hepatopancreas of adult goldfish. In addition, we also find that [C(8)mim]Br causes a remarkable increase in malondialdehyde (MDA) levels in the hepatopancreas of adult goldfish, and thus we think that the MDA level change can be a biomarker of [C(8)mim]Br toxicity in goldfish. The present study indicates that ionic liquids can be a threat to the survival, growth, and development of the fish population once they are accidentally leaked into aquatic ecosystems.
Asunto(s)
Antioxidantes/metabolismo , Carpa Dorada/crecimiento & desarrollo , Carpa Dorada/metabolismo , Imidazoles/toxicidad , Animales , Catalasa/efectos de los fármacos , Catalasa/metabolismo , Glutatión/efectos de los fármacos , Glutatión/metabolismo , Glutatión Peroxidasa/efectos de los fármacos , Glutatión Peroxidasa/metabolismo , Intestinos/efectos de los fármacos , Líquidos Iónicos/química , Líquidos Iónicos/toxicidad , Riñón/efectos de los fármacos , Peroxidación de Lípido/efectos de los fármacos , Hígado/efectos de los fármacos , Malondialdehído/análisis , Malondialdehído/toxicidad , Estrés Oxidativo/efectos de los fármacos , Superóxido Dismutasa/efectos de los fármacos , Superóxido Dismutasa/metabolismo , Pruebas de Toxicidad AgudaRESUMEN
OBJECTIVES: To investigate the effects of salvianolic acid B (Sal-B) on pancreatic damage in experimental chronic pancreatitis. METHODS: Chronic pancreatitis was induced by infusion of trinitrobenzene sulfonic acid into the pancreatic duct in male Sprague-Dawley rats. From the beginning of 5 weeks, the rats in group 2 were treated with Sal-B by gavage for 8 weeks. Salvianolic acid B was given at a daily dose of 10 mg/kg body weight. At the end of 12 weeks, the levels of serum biochemical indexes were measured on an automatic biochemical analyzer; serum hyaluronic acid and laminin levels were determined by radioimmunoassay; pancreatic tissue malondialdehyde (MDA) was analyzed, and the degree of pancreatic damage was determined. RESULTS: The level of serum biochemical indexes were similar in all groups (P > 0.05 for all). Salvianolic acid B treatment did not obviously reduce hyaluronic acid and laminin concentration in blood (P > 0.05). Salvianolic acid B treatment decreased MDA concentration in pancreatic tissue (P < 0.01). Salvianolic acid B clearly improved pancreatic histological findings and prevented the activation of pancreatic stellate cells. CONCLUSIONS: Sal-B treatment decreased MDA concentration in pancreatic tissue, attenuated morphological pancreatic damage, and prevented the activation of pancreatic stellate cells in experimental chronic pancreatitis.