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1.
Strahlenther Onkol ; 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38498173

RESUMO

OBJECTIVE: This study aims to examine the ability of deep learning (DL)-derived imaging features for the prediction of radiation pneumonitis (RP) in locally advanced non-small-cell lung cancer (LA-NSCLC) patients. MATERIALS AND METHODS: The study cohort consisted of 90 patients from the Fudan University Shanghai Cancer Center and 59 patients from the Affiliated Hospital of Jiangnan University. Occurrences of RP were used as the endpoint event. A total of 512 3D DL-derived features were extracted from two regions of interest (lung-PTV and PTV-GTV) delineated on the pre-radiotherapy planning CT. Feature selection was done using LASSO regression, and the classification models were built using the multilayered perceptron method. Performances of the developed models were evaluated by receiver operating characteristic curve analysis. In addition, the developed models were supplemented with clinical variables and dose-volume metrics of relevance to search for increased predictive value. RESULTS: The predictive model using DL features derived from lung-PTV outperformed the one based on features extracted from PTV-GTV, with AUCs of 0.921 and 0.892, respectively, in the internal test dataset. Furthermore, incorporating the dose-volume metric V30Gy into the predictive model using features from lung-PTV resulted in an improvement of AUCs from 0.835 to 0.881 for the training data and from 0.690 to 0.746 for the validation data, respectively (DeLong p < 0.05). CONCLUSION: Imaging features extracted from pre-radiotherapy planning CT using 3D DL networks could predict radiation pneumonitis and may be of clinical value for risk stratification and toxicity management in LA-NSCLC patients. CLINICAL RELEVANCE STATEMENT: Integrating DL-derived features with dose-volume metrics provides a promising noninvasive method to predict radiation pneumonitis in LA-NSCLC lung cancer radiotherapy, thus improving individualized treatment and patient outcomes.

2.
Chemistry ; 27(40): 10405-10412, 2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-33938057

RESUMO

Inspired by the spongy bone structures, three-dimensional (3D) sponge-like carbons with meso-microporous structures are synthesized through one-step electro-reduction of CO2 in molten carbonate Li2 CO3 -Na2 CO3 -K2 CO3 at 580 °C. SPC4-0.5 (spongy porous carbon obtained by electrolysis of CO2 at 4 A for 0.5 h) is synthesized with the current efficiency of 96.9 %. SPC4-0.5 possesses large electrolyte ion accessible surface area, excellent wettability and electronical conductivity, ensuring the fast and effective mass and charge transfer, which make it an advcanced supercapacitor electrode material. SPC4-0.5 exhibits a specific capacitance as high as 373.7 F g-1 at 0.5 A g-1 , excellent cycling stability (retaining 95.9 % of the initial capacitance after 10000 cycles at 10 A g-1 ), as well as high energy density. The applications of SPC4-0.5 in quasi-solid-state symmetric supercapacitor and all-solid-state flexible devices for energy storage and wearable piezoelectric sensor are investigated. Both devices show considerable capacitive performances. This work not only presents a controllable and facile synthetic route for the porous carbons but also provides a promising way for effective carbon reduction and green energy production.


Assuntos
Dióxido de Carbono , Carbono , Capacitância Elétrica , Eletrodos , Porosidade
3.
Drug Metab Dispos ; 48(6): 499-507, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32193215

RESUMO

It was recently disclosed that CYP3A is responsible for the tertiary stereoselective oxidations of deoxycholic acid (DCA), which becomes a continuum mechanism of the host-gut microbial cometabolism of bile acids (BAs) in humans. This work aims to investigate the species differences of BA redox metabolism and clarify whether the tertiary metabolism of DCA is a conserved pathway in preclinical animals. With quantitative determination of the total unconjugated BAs in urine and fecal samples of humans, dogs, rats, and mice, it was confirmed that the tertiary oxidized metabolites of DCA were found in all tested animals, whereas DCA and its oxidized metabolites disappeared in germ-free mice. The in vitro metabolism data of DCA and the other unconjugated BAs in liver microsomes of humans, monkeys, dogs, rats, and mice showed consistencies with the BA-profiling data, confirming that the tertiary oxidation of DCA is a conserved pathway. In liver microsomes of all tested animals, however, the oxidation activities toward DCA were far below the murine-specific 6ß-oxidation activities toward chenodeoxycholic acid (CDCA), ursodeoxycholic acid, and lithocholic acid (LCA), and 7-oxidation activities toward murideoxycholic acid and hyodeoxycholic acid came from the 6-hydroxylation of LCA. These findings provided further explanations for why murine animals have significantly enhanced downstream metabolism of CDCA compared with humans. In conclusion, the species differences of BA redox metabolism disclosed in this work will be useful for the interspecies extrapolation of BA biology and toxicology in translational researches. SIGNIFICANCE STATEMENT: It is important to understand the species differences of bile acid metabolism when deciphering biological and hepatotoxicology findings from preclinical studies. However, the species differences of tertiary bile acids are poorly understood compared with primary and secondary bile acids. This work confirms that the tertiary oxidation of deoxycholic acid is conserved among preclinical animals and provides deeper understanding of how and why the downstream metabolism of chenodeoxycholic acid dominates that of cholic acid in murine animals compared with humans.


Assuntos
Ácidos e Sais Biliares/metabolismo , Citocromo P-450 CYP3A/metabolismo , Animais , Ácidos e Sais Biliares/análise , Ácidos e Sais Biliares/química , Cães , Avaliação Pré-Clínica de Medicamentos , Fezes/química , Feminino , Vida Livre de Germes , Humanos , Hidroxilação , Masculino , Camundongos , Microssomos Hepáticos , Oxirredução , Ratos , Especificidade da Espécie , Estereoisomerismo , Especificidade por Substrato , Espectrometria de Massas em Tandem , Urina/química
4.
Drug Metab Dispos ; 48(8): 662-672, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32499339

RESUMO

This work aims to investigate how the bile acid metabolism of newborns differs from that of adults along the axis of primary, secondary, and tertiary bile acids (BAs). The total unconjugated BA profiles were quantitatively determined by enzyme digestion techniques in urine of 21 newborns born by cesarean section, 29 healthy parturient women, 30 healthy males, and 28 healthy nonpregnant females. As expected, because of a lack of developed gut microbiota, newborns exhibited poor metabolism of secondary BAs. Accordingly, the tertiary BAs contributed limitedly to the urinary excretion of BAs in newborns despite their tertiary-to-secondary ratios significantly increasing. As a result, the primary BAs of newborns underwent extensive oxidative metabolism, resulting in elevated urinary levels of some fetal-specific BAs, including 3-dehydroCA, 3ß,7α,12α-trihydroxy-5ß-cholan-24-oic acid, 3α,12-oxo-hydroxy-5ß-cholan-24-oic acid, and nine tetrahydroxy-cholan-24-oic acids (Tetra-BAs). Parturient women had significantly elevated urinary levels of tertiary BAs and fetal-specific BAs compared with female control, indicating that they may be excreted into amniotic fluid for maternal disposition. An in vitro metabolism assay in infant liver microsomes showed that four Tetra-BAs and 3-dehydroCA were hydroxylated metabolites of cholate, glycocholate, and particularly taurocholate. However, the recombinant cytochrome P450 enzyme assay found that the fetal-specific CYP3A7 did not contribute to these oxidation metabolisms as much as expected compared with CYP3A4. In conclusion, newborns show a BA metabolism pattern predominated by primary BA oxidations due to immaturity of secondary BA metabolism. Translational studies following this finding may bring new ideas and strategies for both pediatric pharmacology and diagnosis and treatment of perinatal cholestasis-associated diseases. SIGNIFICANCE STATEMENT: The prenatal BA disposition is different from adults because of a lack of gut microbiota. However, how the BA metabolism of newborns differs from that of adults along the axis of primary, secondary, and tertiary BAs remains poorly defined. This work demonstrated that the urinary BA profiles of newborns born by cesarean section are characterized by oxidative metabolism of primary BAs, in which the fetal-specific CYP3A7 plays a limited role in the downstream oxidation metabolism of cholate.


Assuntos
Ácidos e Sais Biliares/metabolismo , Colatos/metabolismo , Citocromo P-450 CYP3A/metabolismo , Recém-Nascido/metabolismo , Adulto , Fatores Etários , Ácidos e Sais Biliares/urina , Cesárea , Colatos/urina , Feminino , Voluntários Saudáveis , Humanos , Masculino , Troca Materno-Fetal , Microssomos Hepáticos , Oxirredução , Gravidez
5.
Langmuir ; 36(41): 12357-12365, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-33030345

RESUMO

A novel three-dimensional purple dandelion-like hierarchical Ag2O@CoO heterojunction with an appropriate redox potential was constructed by chemical precipitation of Ag2O nanoparticle on flower-like CoO. By feat of this hierarchical structure, the Ag2O@CoO photocathode showed significantly high photoelectroreduction activities toward p-nitrophenol (p-NP) and Cr(VI). The high performance of Ag2O@CoO was mainly attributed to the specific structural characteristics and synergistic effect of each chemical component. This hierarchical structure could effectively increase the specific surface area, provide more exposed active edges, and be beneficial for multiple light reflection/scattering channels and light utilization efficiency. The introduction of Ag2O optimized the composition and further improved the band structure, resulting in an improved separation of photogenerated electrons and holes. The unique photocathode achieves a removal efficiency of 86% for photoelectrocatalytic p-NP degradation after 120 min and 95% for Cr(VI) after 40 min under visible light irradiation with excellent stability. This research provided a simple way for the synthesis of photoelectrocatalytic material with potential applications in the field of environmental governance with visible light illumination.

6.
Microbiol Immunol ; 64(1): 63-71, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31552680

RESUMO

Specific tumor microenvironment signaling might prevent the maturation of dendritic cells (DCs) with tolerogenic and immunosuppressive potential accounting for antigen-specific unresponsiveness in the lymphoid organs and in the periphery. In the present study, dendritic cells treated with LLC lung cancer cell or 4T1 breast cancer cell culture supernatants significantly down-regulated the expression of co-stimulatory molecules MHC-II, CD40, CD80, but up-regulated the inhibitory molecule PD-L1/L2, VISTA, and increased the messengerRNA levels of interleukin (IL)-6, arginase I, and IL-10, but decreased tumor necrosis factor-α and IL-12a. RNA was isolated from the dendritic cells with or without tumor supernatant stimulation and RNA sequencing was done. Then the differential expression genes were sorted, the candidate genes were analyzed and pathway enrichment analysis was done, and the associated protein-protein interaction network (PPI) was established. After integrated bioinformatical analysis, 405 (279 up-regulated and 126 down-regulated) consistently differential expression genes were identified. Using gene ontology and pathway analysis, it was found that differential expression genes were mainly enriched in the immune response, cell-cell interaction, hemostasis, and cell surface interactions with the vascular wall. The PPI data demonstrated that 236 nodes were classified with 1072 edges, and the most remarkable three modules involved 53 central node genes associated with cell survival, cell-substrate adhesion, chemotaxis, migration, immune response, and complement receptor mediated signaling pathway. These findings revealed the immune status of dendritic cells in the tumor environment.


Assuntos
Biologia Computacional , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Microambiente Tumoral/imunologia , Antígenos B7/metabolismo , Antígeno B7-1/metabolismo , Antígeno B7-H1/metabolismo , Neoplasias da Mama , Antígenos CD40/metabolismo , Linhagem Celular Tumoral , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Interleucina-10/metabolismo , Interleucina-12 , Neoplasias Pulmonares , Proteína 2 Ligante de Morte Celular Programada 1/metabolismo , Mapas de Interação de Proteínas , RNA Mensageiro/metabolismo , Transdução de Sinais , Fator de Necrose Tumoral alfa/metabolismo
7.
J Sep Sci ; 43(16): 3216-3223, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32506776

RESUMO

In order to investigate the protective effects of Rhodiola crenulata extract on Alzheimer's disease, a brain metabolomics study in rats was conducted by high performance liquid chromatography coupled with Fourier transform ion cyclotron resonance mass spectrometry. Rat model was constructed by bilateral hippocampal injection of amyloid-ß peptide and immunohistochemistry was performed to evaluate the pharmacological effect of Rhodiola crenulata extract. Multivariate statistical analysis was used to discover potential biomarkers in rat brain and related metabolic pathways analysis was conducted to elucidate the action mechanism of Rhodiola crenulata extract. As a result, a total of 19 metabolites contributing to Alzheimer's disease progress were identified and nine of them were restored to the normal levels after drug administration. Pathway analysis revealed that the protective effects of Rhodiola crenulata extract are related to the regulation of glutathione metabolism and arachidonic acid metabolism in rat brain. In conclusion, this work demonstrates that the developed metabolomics method is useful to investigate the protective effects of Rhodiola crenulata extract against Alzheimer's disease. These outcomes may further provide reliable evidence to illuminate the intervention mechanism of other traditional Chinese medicines on Alzheimer's disease.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Encéfalo/efeitos dos fármacos , Metabolômica , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Rhodiola/química , Doença de Alzheimer/metabolismo , Animais , Encéfalo/metabolismo , Análise de Fourier , Masculino , Espectrometria de Massas , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Raízes de Plantas/química , Substâncias Protetoras/química , Substâncias Protetoras/metabolismo , Ratos , Ratos Sprague-Dawley
8.
Opt Express ; 27(16): A1207-A1215, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31510509

RESUMO

ZnO is a promising short-wavelength light-emitting materials for its wide bandgap (3.37 eV) and large exciton binding energy (∼60 meV), however, practical p-type doped ZnO is the main challenge in this field. Here, Blue light-emitting diodes (LEDs) based on the homogeneous junctions of Sb doped ZnO nanowire arrays grown on Ga doped ZnO single crystal substrate are fabricated. Element analysis, FET and Hall-effect measurements demonstrate that the Sb atom has been successfully doped into ZnO nanowires to from p-type conductivity. On the benefit of high quality of nano-size homojunction, the fabricated LED shows low turn-on voltage turn-on voltage as low as 3.4 V and strong blue emission peak located at 425 nm at room temperature, which originate from interfacial recombination of ZnO nanowire p-n homojunctions. The present blue LED based on ZnO material may have potential applications in short-wavelength optoelectronic devices.

9.
Drug Metab Dispos ; 47(6): 574-581, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30918015

RESUMO

The primary bile acids (BAs) synthesized from cholesterol in the liver are converted to secondary BAs by gut microbiota. It was recently disclosed that the major secondary BA, deoxycholate (DCA) species, is stereoselectively oxidized to tertiary BAs exclusively by CYP3A enzymes. This work subsequently investigated the in vitro oxidation kinetics of DCA at C-1ß, C-3ß, C-4ß, C-5ß, C-6α, C-6ß, and C-19 in recombinant CYP3A enzymes and naive enzymes in human liver microsomes (HLMs). The stereoselective oxidation of DCA fit well with Hill kinetics at 1-300 µM in both recombinant CYP3A enzymes and pooled HLMs. With no contributions or trace contributions from CYP3A5, CYP3A7 favors oxidation at C-19, C-4ß, C-6α, C-3ß, and C-1ß, whereas CYP3A4 favors the oxidation at C-5ß and C-6ß compared with each other. Correlation between DCA oxidation and testosterone 6ß-hydroxylation in 14 adult single-donor HLMs provided proof-of-concept evidence that DCA 19-hydroxylation is an in vitro marker reaction for CYP3A7 activity, whereas oxidation at other sites represents mixed indicators for CYP3A4 and CYP3A7 activities. Deactivation caused by DCA-induced cytochrome P450-cytochrome P420 conversion, as shown by the spectral titrations of isolated CYP3A proteins, was observed when DCA levels were near or higher than the critical micelle concentration (about 1500 µM). Unlike CYP3A4, CYP3A7 showed abnormally elevated activities at 500 and 750 µM, which might be associated with an altered affinity for DCA multimers. The disclosed kinetic and functional roles of CYP3A isoforms in disposing of the gut bacteria-derived DCA may help in understanding the structural and functional mechanisms of CYP3A.


Assuntos
Biomarcadores/metabolismo , Citocromo P-450 CYP3A/metabolismo , Ácido Desoxicólico/metabolismo , Humanos , Hidroxilação/fisiologia , Cinética , Fígado/metabolismo , Microssomos Hepáticos/metabolismo , Oxirredução
10.
Drug Metab Dispos ; 47(3): 283-294, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30606729

RESUMO

The gut microbiota modifies endogenous primary bile acids (BAs) to produce exogenous secondary BAs, which may be further metabolized by cytochrome P450 enzymes (P450s). Our primary aim was to examine how the host adapts to the stress of microbe-derived secondary BAs by P450-mediated oxidative modifications on the steroid nucleus. Five unconjugated tri-hydroxyl BAs that were structurally and/or biologically associated with deoxycholate (DCA) were determined in human biologic samples by liquid chromatography-tandem mass spectrometry in combination with enzyme-digestion techniques. They were identified as DCA-19-ol, DCA-6ß-ol, DCA-5ß-ol, DCA-6α-ol, DCA-1ß-ol, and DCA-4ß-ol based on matching in-laboratory synthesized standards. Metabolic inhibition assays in human liver microsomes and recombinant P450 assays revealed that CYP3A4 and CYP3A7 were responsible for the regioselective oxidations of both DCA and its conjugated forms, glycodeoxycholate (GDCA) and taurodeoxycholate (TDCA). The modification of secondary BAs to tertiary BAs defines a host liver (primary BAs)-gut microbiota (secondary BAs)-host liver (tertiary BAs) axis. The regioselective oxidations of DCA, GDCA, and TDCA by CYP3A4 and CYP3A7 may help eliminate host-toxic DCA species. The 19- and 4ß-hydroxylation of DCA species demonstrated outstanding CYP3A7 selectivity and may be useful as indicators of CYP3A7 activity.


Assuntos
Citocromo P-450 CYP3A/metabolismo , Ácido Desoxicólico/metabolismo , Microbioma Gastrointestinal/fisiologia , Adulto , Ácido Desoxicólico/sangue , Ácido Desoxicólico/toxicidade , Ácido Desoxicólico/urina , Feminino , Voluntários Saudáveis , Humanos , Hidroxilação , Fígado/metabolismo , Masculino , Microssomos Hepáticos , Oxirredução , Adulto Jovem
11.
FASEB J ; 31(4): 1449-1460, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28007782

RESUMO

Endogenous fatty acid metabolism that results in elongation and desaturation lipid products is thought to play a role in the development of type 2 diabetes mellitus (T2DM). In this study, we evaluated the potential of estimated elongase and desaturase activities for use as predictive markers for T2DM remission after Roux-en-Y gastric bypass (RYGB). The results of a targeted metabolomics approach from 2 independent studies were used to calculate 24 serum FA concentration ratios (product/precursor). Gene expression data from an open public data set was also analyzed. In a longitudinal study of 38 obese diabetic patients with RYGB, we found higher baseline stearic acid/palmitic acid (S/P) ratio. This ratio reflects an elovl6-encoded elongase enzyme activity that has been found to be associated with greater possibility for diabetes remission after RYGB [odds ratio, 2.16 (95% CI 1.10-4.26)], after adjustment for age, gender, body mass index, diabetes duration, glycosylated hemoglobin A1c, and fasting C-peptide. Our results were validated by examination of postsurgical elovl6 gene expression in morbidly obese patients. The association of S/P with the metabolic status of obese individuals was further validated in a cross-sectional cohort of 381 participants. In summary, higher baseline S/P was associated with greater probability of diabetes remission after RYGB and may serve as a diagnostic marker in preoperative patient assessment. - Zhao, L., Ni, Y., Yu, H., Zhang, P., Zhao, A., Bao, Y., Liu, J., Chen, T., Xie, G., Panee, J., Chen, W., Rajani, C., Wei, R., Su, M., Jia, W., Jia, W. Serum stearic acid/palmitic acid ratio as a potential predictor of diabetes remission after Roux-en-Y gastric bypass in obesity.


Assuntos
Diabetes Mellitus/sangue , Derivação Gástrica , Obesidade/cirurgia , Ácido Palmítico/sangue , Ácidos Esteáricos/sangue , Acetiltransferases/genética , Acetiltransferases/metabolismo , Adulto , Idoso , Biomarcadores/sangue , Diabetes Mellitus/epidemiologia , Elongases de Ácidos Graxos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/sangue , Obesidade/complicações
12.
Anal Bioanal Chem ; 410(21): 5287-5300, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29907951

RESUMO

Host-gut microbiota metabolic interactions are closely associated with health and disease. A manifestation of such co-metabolism is the vast structural diversity of bile acids (BAs) involving both oxidative stereochemistry and conjugation. Herein, we describe the development and validation of a LC-MS-based method for the analysis of human C24 BA metabolome in serum and urine. The method has high throughput covering the discrimination of oxidative stereochemistry of unconjugated species in a 15-min analytical cycle. The validated quantitative performance provided an indirect way to ascertain the conjugation patterns of BAs via enzyme-digestion protocols that incorporated the enzymes, sulfatase, ß-glucuronidase, and choloylglycine hydrolase. Application of the method has led to the detection of at least 70 unconjugated BAs including 27 known species and 43 newly found species in the post-prandial serum and urine samples from 7 nonalcoholic steatohepatitis patients and 13 healthy volunteers. Newly identified unconjugated BAs included 3α, 12ß-dihydroxy-5ß-cholan-24-oic acid, 12α-hydroxy-3-oxo-5ß-cholan-24-oic acid, and 3α, 7α, 12ß-trihydroxy-5ß-cholan-24-oic acid. High-definition negative fragment spectra of the other major unknown species were acquired to facilitate future identification endeavors. An extensive conjugation pattern is the major reason for the "invisibility" of the newly found BAs to other common analytical methods. Metabolomic analysis of the total unconjugated BA profile in combination with analysis of their conjugation patterns and urinary excretion tendencies have provided substantial insights into the interconnected roles of host and gut microbiota in maintaining BA homeostasis. It was proposed that the urinary total BA profile may serve as an ideal footprint for the functional status of the host-gut microbial BA co-metabolism. In summary, this work provided a powerful tool for human C24 BA metabolome analysis that bridges the gap between GC-MS techniques in the past age and LC-MS techniques currently prevailing in biomedical researches. Further applications of the present method in clinical, translational research, and other biomedical explorations will continue to boost the construction of a host-gut microbial co-metabolism network of BAs and thus facilitate the decryption of BA-mediated host-gut microbiota crosstalk in health and diseases. Graphical abstract ᅟ.


Assuntos
Ácidos e Sais Biliares/química , Ácidos e Sais Biliares/metabolismo , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Ácidos e Sais Biliares/sangue , Ácidos e Sais Biliares/urina , Humanos , Estrutura Molecular
13.
Pestic Biochem Physiol ; 150: 97-104, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30195394

RESUMO

Bemisia tabaci (Gennadius) Q biotype (BTQ) has spread to many tropical and subtropical regions over the past several decades. This may reflect an advantage biotype Q has over closely related forms in having greater thermal and/or insecticide resistance, although the effects of higher temperatures on insecticide tolerance of BTQ has, to date, been largely ignored. In this study, the effects of elevated temperatures on BTQ's tolerance to the insecticide thiamethoxam were investigated. The effect on the activities of detoxifying enzymes [carboxylesterase (CarE), glutathione S-transferase (GST), and cytochrome P450 monooxygenase (P450)] and expression profiling of eleven genes of detoxifying enzymes were also determined. In addition, RNA interference (RNAi) and bioassay methods were used to further identify the function of CYP6CM1 in tolerance to thiamethoxam following exposure to higher temperatures. The results showed that elevated temperatures were responsible for causing different outcomes in the tolerance of BTQ to thiamethoxam: Temperatures of 35 °C or higher decreased the tolerance of BTQ to thiamethoxam, while a moderately high temperature of 31 °C increased the tolerance. The high temperature influenced the tolerance of BTQ by affecting the activity of P450. Quantitative real-time PCR (qPCR) showed that CYP6CM1 was significantly up-regulated in most treatments at 31 °C, but was suppressed at 35 °C, which was closely associated with the mortality rates. Feeding on double-stranded RNA (dsRNA) of CYP6CM1 significantly reduced the mRNA levels of the target gene in the adults, and dramatically decreased tolerance to thiamethoxam induced by a temperature of 31 °C for 6 h. Our finding provides useful information to better understand the invasion mechanism of BTQ.


Assuntos
Hemípteros/efeitos dos fármacos , Temperatura Alta , Resistência a Inseticidas/genética , Inseticidas/farmacologia , Animais , Sistema Enzimático do Citocromo P-450/metabolismo , Perfilação da Expressão Gênica , Interferência de RNA
14.
Int J Toxicol ; 37(2): 144-154, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29587557

RESUMO

Polycystic kidney disease is characterized by the progressive development of kidney cysts and declining renal function with frequent development of cysts in other organs including the liver. The polycystic kidney (PCK) rat is a rodent model of polycystic liver disease that has been used to study hepatorenal disease progression and evaluate pharmacotherapeutic interventions. Biomarkers that describe the cyst progression, liver impairment, and/or hepatic cyst burden could provide clinical utility for this disease. In the present study, hepatic cyst volume was measured by magnetic resonance imaging in PCK rats at 12, 16, and 20 weeks. After 20 weeks, Sprague Dawley (n = 4) and PCK (n = 4) rats were sacrificed and 42 bile acids were analyzed in the liver, bile, serum, and urine by liquid chromatography coupled to tandem mass spectrometry. Bile acid profiling revealed significant increases in total bile acids (molar sum of all measured bile acids) in the liver (13-fold), serum (6-fold), and urine (3-fold) in PCK rats, including those speciated bile acids usually associated with hepatotoxicity. Total serum bile acids correlated with markers of liver impairment (liver weight, total liver bile acids, total hepatotoxic liver bile acids, and cyst volume [ r > 0.75; P < 0.05]). Based on these data, serum bile acids may be useful biomarkers of liver impairment in polycystic hepatorenal disease.


Assuntos
Ácidos e Sais Biliares/metabolismo , Fígado/metabolismo , Doenças Renais Policísticas/metabolismo , Animais , Biomarcadores/metabolismo , Modelos Animais de Doenças , Fígado/diagnóstico por imagem , Fígado/patologia , Imageamento por Ressonância Magnética , Masculino , Doenças Renais Policísticas/patologia , Ratos Sprague-Dawley
15.
Anal Chem ; 89(10): 5565-5577, 2017 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-28437060

RESUMO

The ability to identify and quantify small molecule metabolites derived from gut microbial-mammalian cometabolism is essential for the understanding of the distinct metabolic functions of the microbiome. To date, analytical protocols that quantitatively measure a complete panel of microbial metabolites in biological samples have not been established but are urgently needed by the microbiome research community. Here, we report an automated high-throughput quantitative method using a gas chromatography/time-of-flight mass spectrometry (GC/TOFMS) platform to simultaneously measure over one hundred microbial metabolites in human serum, urine, feces, and Escherichia coli cell samples within 15 min per sample. A reference library was developed consisting of 145 methyl and ethyl chloroformate (MCF and ECF) derivatized compounds with their mass spectral and retention index information for metabolite identification. These compounds encompass different chemical classes including fatty acids, amino acids, carboxylic acids, hydroxylic acids, and phenolic acids as well as benzoyl and phenyl derivatives, indoles, etc., that are involved in a number of important metabolic pathways. Within an optimized range of concentrations and sample volumes, most derivatives of both reference standards and endogenous metabolites in biological samples exhibited satisfactory linearity (R2 > 0.99), good intrabatch reproducibility, and acceptable stability within 6 days (RSD < 20%). This method was further validated by examination of the analytical variability of 76 paired human serum, urine, and fecal samples as well as quality control samples. Our method involved using high-throughput sample preparation, measurement with automated derivatization, and rapid GC/TOFMS analysis. Both techniques are well suited for microbiome metabolomics studies.


Assuntos
Escherichia coli/metabolismo , Formiatos/química , Ésteres do Ácido Fórmico/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Metaboloma , Automação , Escherichia coli/química , Fezes/química , Humanos , Análise de Componente Principal , Reprodutibilidade dos Testes , Soro/química , Urina/química
16.
Anal Bioanal Chem ; 409(23): 5533-5545, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28689325

RESUMO

Bile acids (BAs) are cholesterol metabolites with important biological functions. They undergo extensive host-gut microbial co-metabolisms during the enterohepatic circulation, creating a vast structural diversity and resulting in great challenges to separate and detect them. Based on the bioanalytical reports in the past decade, this work developed three chromatographic gradient methods to separate a total of 48 BA standards on an ethylene-bridged hybrid (BEH) C18 column and high-strength silica (HSS) T3 column and accordingly unraveled the factors affecting the separation and detection of them by liquid chromatography coupled with mass spectrometry (LC-MS). It was shown that both the acidity and ammonium levels in mobile phases reduced the electrospray ionization (ESI) of BAs as anions of [M-H]-, especially for those unconjugated ones without 12-hydroxylation. It was also found that the retention of taurine conjugates on the BEH C18 column was sensitive to the strength of formic acid and ammonium in mobile phases. By using the volatile buffers with an equivalent ammonium level as mobile phases, we comprehensively demonstrated the effects of the elution pH value on the retention behaviors of BAs on both the BEH C18 column and HSS T3 column. Based on the retention data acquired on a C18 column, we presented the ionization constants (pK a) of various BAs with the widest coverage beyond those of previous reports. When we made attempts to establish the structure-retention relationships (SRRs) of BAs, the lack of discriminative structural descriptors for BA stereoisomers emerged as the bottleneck problem. The methods and results presented in this work are especially useful for the development of reliable, sensitive, high-throughput, and robust LC-MS bioanalytical protocols for the quantitative metabolomic studies. Graphical Abstract Nonlinear curve fitting of capacity factors and elution pH value for the separation of common unconjugated bile acids.


Assuntos
Ácidos e Sais Biliares/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Animais , Ácidos e Sais Biliares/análise , Humanos , Concentração de Íons de Hidrogênio
17.
Arch Toxicol ; 91(1): 189-202, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26883664

RESUMO

Arsenic (+3 oxidation state) methyltransferase (As3mt) is the key enzyme in the pathway for methylation of inorganic arsenic (iAs). Altered As3mt expression and AS3MT polymorphism have been linked to changes in iAs metabolism and in susceptibility to iAs toxicity in laboratory models and in humans. As3mt-knockout mice have been used to study the association between iAs metabolism and adverse effects of iAs exposure. However, little is known about systemic changes in metabolism of these mice and how these changes lead to their increased susceptibility to iAs toxicity. Here, we compared plasma and urinary metabolomes of male and female wild-type (WT) and As3mt-KO (KO) C57BL/6 mice and examined metabolomic shifts associated with iAs exposure in drinking water. Surprisingly, exposure to 1 ppm As elicited only small changes in the metabolite profiles of either WT or KO mice. In contrast, comparisons of KO mice with WT mice revealed significant differences in plasma and urinary metabolites associated with lipid (phosphatidylcholines, cytidine, acyl-carnitine), amino acid (hippuric acid, acetylglycine, urea), and carbohydrate (L-sorbose, galactonic acid, gluconic acid) metabolism. Notably, most of these differences were sex specific. Sex-specific differences were also found between WT and KO mice in plasma triglyceride and lipoprotein cholesterol levels. Some of the differentially changed metabolites (phosphatidylcholines, carnosine, and sarcosine) are substrates or products of reactions catalyzed by other methyltransferases. These results suggest that As3mt KO alters major metabolic pathways in a sex-specific manner, independent of iAs treatment, and that As3mt may be involved in other cellular processes beyond iAs methylation.


Assuntos
Intoxicação por Arsênico/enzimologia , Arsênio/toxicidade , Metabolismo Energético/efeitos dos fármacos , Metaboloma/efeitos dos fármacos , Metiltransferases/metabolismo , Poluentes Químicos da Água/toxicidade , Aminoácidos/metabolismo , Animais , Arsênio/sangue , Arsênio/metabolismo , Arsênio/urina , Intoxicação por Arsênico/sangue , Intoxicação por Arsênico/metabolismo , Intoxicação por Arsênico/urina , Arsenicais/sangue , Arsenicais/metabolismo , Arsenicais/urina , Biomarcadores/sangue , Biomarcadores/urina , Biotransformação , Metabolismo dos Carboidratos/efeitos dos fármacos , Resistência a Medicamentos , Feminino , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Metilação , Metiltransferases/genética , Camundongos Endogâmicos C57BL , Camundongos Knockout , Caracteres Sexuais , Toxicocinética , Poluentes Químicos da Água/sangue , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/urina
18.
Br J Neurosurg ; 31(2): 217-222, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27760466

RESUMO

BACKGROUND: Symptomatic intracranial hemorrhage (ICH) may lead to permanent neurological disability of patients and has impeded the extensive clinical application of deep brain stimulation (DBS). The present study was conducted to discuss the incidence, prevention, and treatment of symptomatic ICH after DBS surgery. METHODS: From January 2009 to December 2014, 396 patients underwent DBS with a total of 691 implanted leads. In all, 10 patients had symptomatic ICH. We analyzed these cases' clinical characteristics, including comorbid diagnoses and coagulation profile. We described the onset of ICH, imaging features, clinical manifestations, treatment, neurological impairment, and outcome of DBS. RESULTS: Of the 10 patients with symptomatic ICH, 2 had hypertension. Three cases of ICH occurred within 12 h of the procedure; four cases within 24 h. Five experienced grand mal seizures concurrently with hemorrhage. Unilateral frontal lobe hemorrhage occurred in all cases. In seven cases, hematomas occurred around the electrodes. Some hematomas were not well-circumscribed and had perihematomal edema. Conservative therapy was administered to 8 patients, and 2 patients underwent craniotomy and hematoma evacuation. All electrodes were successfully preserved. Neurological dysfunction in all patients gradually improved. Nine patients ultimately experienced effective symptom relief of Parkinson's disease with DBS. CONCLUSIONS: Symptomatic ICH should be identified as soon as possible after implantation surgery and treated effectively to limit neurological deficit and preserve DBS leads.


Assuntos
Estimulação Encefálica Profunda/efeitos adversos , Hemorragias Intracranianas/etiologia , Hemorragias Intracranianas/terapia , Procedimentos Neurocirúrgicos/efeitos adversos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Edema Encefálico/etiologia , Edema Encefálico/prevenção & controle , Edema Encefálico/terapia , Criança , Comorbidade , Craniotomia , Drenagem , Eletrodos Implantados/efeitos adversos , Feminino , Lobo Frontal , Humanos , Hemorragia Intracraniana Hipertensiva/etiologia , Hemorragia Intracraniana Hipertensiva/prevenção & controle , Hemorragia Intracraniana Hipertensiva/terapia , Hemorragias Intracranianas/prevenção & controle , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Exame Neurológico , Doença de Parkinson/cirurgia , Complicações Pós-Operatórias/prevenção & controle , Adulto Jovem
19.
J Proteome Res ; 15(4): 1333-41, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-26956768

RESUMO

Metabolic profiling has great potential to help the diagnosis and prognosis of cancer patients. Fanconi Anemia (FA) tumor-suppressor signaling has been instrumental in understanding human tumorigenesis. However, this instrumental understanding has never been demonstrated at the metabolic level. Here, we show that impaired FA signaling can lead cells to exhibit metabolic signatures of tumorigenesis. This is consistent with our original studies of the roles of FA signaling in suppressing non-FA tumorigenesis at functional and genetic levels. Using ultraperformance liquid chromatography-mass spectroscopy and gas chromatography-mass spectrometry, we characterized metabolic alterations in bladder cancer cells carrying an intact or impaired FA pathway. The latter was obtained by ectopically expressing FAVL (FAVL-high), which we previously found to be capable of inactivating FA signaling. A total of 18 metabolites, end products of cell proliferation or apoptosis, were significantly different between FAVL-high and -low cells. Methionine, phenylalanine, and threonine, resulting from a tumorigenic process, were substantially increased in FAVL-high cells. With this study, we achieved genomic, functional, and metabolomic characterization of the roles of FA signaling in the development of human cancer. Furthermore, this study provides novel insights into how to translate FA basic research into strategies for producing effective biomarkers in human cancer diagnosis and prognosis.


Assuntos
Transformação Celular Neoplásica/metabolismo , Células Epiteliais/metabolismo , Proteína do Grupo de Complementação L da Anemia de Fanconi/genética , Metaboloma , Transdução de Sinais , Processamento Alternativo , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Cromatografia Líquida , Células Epiteliais/patologia , Proteína do Grupo de Complementação L da Anemia de Fanconi/metabolismo , Expressão Gênica , Humanos , Espectrometria de Massas , Metionina/metabolismo , Fenilalanina/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Treonina/metabolismo , Transgenes
20.
Int J Cancer ; 139(8): 1764-75, 2016 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-27273788

RESUMO

Dysregulated bile acids (BAs) are closely associated with liver diseases and attributed to altered gut microbiota. Here, we show that the intrahepatic retention of hydrophobic BAs including deoxycholate (DCA), taurocholate (TCA), taurochenodeoxycholate (TCDCA), and taurolithocholate (TLCA) were substantially increased in a streptozotocin and high fat diet (HFD) induced nonalcoholic steatohepatitis-hepatocellular carcinoma (NASH-HCC) mouse model. Additionally chronic HFD-fed mice spontaneously developed liver tumors with significantly increased hepatic BA levels. Enhancing intestinal excretion of hydrophobic BAs in the NASH-HCC model mice by a 2% cholestyramine feeding significantly prevented HCC development. The gut microbiota alterations were closely correlated with altered BA levels in liver and feces. HFD-induced inflammation inhibited key BA transporters, resulting in sustained increases in intrahepatic BA concentrations. Our study also showed a significantly increased cell proliferation in BA treated normal human hepatic cell lines and a down-regulated expression of tumor suppressor gene CEBPα in TCDCA treated HepG2 cell line, suggesting that several hydrophobic BAs may collaboratively promote liver carcinogenesis.


Assuntos
Ácidos e Sais Biliares/metabolismo , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/metabolismo , Animais , Carcinogênese/metabolismo , Carcinogênese/patologia , Linhagem Celular , Ácido Desoxicólico/metabolismo , Dieta Hiperlipídica , Feminino , Microbioma Gastrointestinal , Células Hep G2 , Humanos , Neoplasias Hepáticas/microbiologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas Experimentais/etiologia , Neoplasias Hepáticas Experimentais/metabolismo , Neoplasias Hepáticas Experimentais/microbiologia , Neoplasias Hepáticas Experimentais/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/microbiologia , Hepatopatia Gordurosa não Alcoólica/patologia , Gravidez , Estreptozocina , Ácido Tauroquenodesoxicólico/metabolismo , Ácido Taurocólico/metabolismo , Ácido Taurolitocólico/metabolismo
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