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1.
Inorg Chem ; 63(12): 5351-5364, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38481142

RESUMO

The reaction of Fe2(mes)4 with the super-bulky amidines and guanidines HLAr*-R (LAr*-R = [(Ar*N)2C(R)]-, Ar* = 2,6-bis(diphenylmethyl)-4-tert-butylphenyl), R = Me (LAr*-Me), tBu (LAr*-tBu), Ph (LAr*-Ph), NiPr2 (LAr*-iPr2N), and Pip (LAr*-Pip)) gives access to the three-coordinate iron-mesityl complexes (LAr*-R)Fe(mes) only where LAr*-R = LAr*-Me, LAr*-Ph, or LAr*-Pip. Subsequent protonolysis with the N-atom transfer reagent Hdbabh (Hdbabh = 2,3:5,6-dibenzo-7-azabicyclo[2.2.1]hepta-2,5-diene) is limited in success, providing in one instance a few crystals of four-coordinate (LAr*-Me)Fe(dbabh)(Hdbabh), while three-coordinate (LAr*-Pip)Fe(dbabh) is synthesized reproducibly. Complexes (LAr*-Me)Fe(dbabh)(Hdbabh) and (LAr*-Pip)Fe(dbabh) are thermally insensitive in solution to temperatures of up to 100 °C. On the other hand, both (LAr*-Me)Fe(dbabh)(Hdbabh) and (LAr*-Pip)Fe(dbabh) show sensitivity to blue LED light (395 nm), undergoing photochemical transformations. For instance, the photolysis of (LAr*-Me)Fe(dbabh)(Hdbabh) leads to N-C bond scission and C-C bond coupling across the -dbabh moieties to give four-coordinate (LAr*-Me)Fe(N=dbabh-dbabhNH2). Photolyzing pyridine-d5 (py-d5) solutions of (LAr*-Pip)Fe(dbabh) at -5 °C produces a new paramagnetic photoproduct, [P]. Due to the thermal sensitivity of compound [P], it has eluded structural characterization; yet, Evans' method measurements suggest that the iron(II) oxidation state is maintained, thereby pointing to the -dbabh moiety as the locus of chemical change. In line with this assessment, addition of excess Me3SiCl to solutions of [P] produces the iron(II) complex (LAr*-Pip)FeCl(py-d5) as shown by 1H NMR spectroscopy. Gas chromatography/mass spectrometry analysis of the solutions of [P] shows a peak in the chromatogram with a molecular mass corresponding to a formulation of C14H11N that cannot be attributed to Hdbabh. This provides evidence for the photochemical-induced isomerization of the -dbabh ligand, revealing a heretofore unknown photochemical sensitivity of this N atom transfer reagent.

2.
PLoS One ; 19(2): e0297615, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38335180

RESUMO

The lack of accuracy in the current prostate specific antigen (PSA) test for prostate cancer (PCa) screening causes around 60-75% of unnecessary prostate biopsies. Therefore, alternative diagnostic methods that have better accuracy and can prevent over-diagnosis of PCa are needed. Researchers have examined various potential biomarkers for PCa, and of those fatty acids (FAs) markers have received special attention due to their role in cancer metabolomics. It has been noted that PCa metabolism prefers FAs over glucose substrates for continued rapid proliferation. Hence, we proposed using a urinary FAs based model as a non-invasive alternative for PCa detection. Urine samples collected from 334 biopsy-designated PCa positive and 232 biopsy-designated PCa negative subjects were analyzed for FAs and lipid related compounds by stir bar sorptive extraction coupled with gas chromatography/mass spectrometry (SBSE-GC/MS). The dataset was split into the training (70%) and testing (30%) sets to develop and validate logit models and repeated for 100 runs of random data partitioning. Over the 100 runs, we confirmed the stability of the models and obtained optimal tuning parameters for developing the final FA based model. A PSA model using the values of the patients' PSA test results was constructed with the same cohort for the purpose of comparing the performances of the FA model against PSA test. The FA final model selected 20 FAs and rendered an AUC of 0.71 (95% CI = 0.67-0.75, sensitivity = 0.48, and specificity = 0.83). In comparison, the PSA model performed with an AUC of 0.51 (95% CI = 0.46-0.66, sensitivity = 0.44, and specificity = 0.71). The study supports the potential use of urinary FAs as a stable and non-invasive alternative test for PCa diagnosis.


Assuntos
Próstata , Neoplasias da Próstata , Masculino , Humanos , Próstata/patologia , Antígeno Prostático Específico , Biomarcadores Tumorais/urina , Neoplasias da Próstata/patologia , Biópsia
3.
Am J Cancer Res ; 14(1): 192-209, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38323272

RESUMO

Prostate cancer (PCa) is the second leading cause of cancer-related death in American men after lung cancer. The current PCa diagnostic method, the serum prostate-specific antigen (PSA) test, is not specific, thus, alternatives are needed to avoid unnecessary biopsies and over-diagnosis of clinically insignificant PCa. To explore the application of metabolomics in such effort, urine samples were collected from 386 male adults aged 44-93 years, including 247 patients with biopsy-proven PCa and 139 with biopsy-proven negative results. The PCa-positive group was further subdivided into two groups: low-grade (ISUP Grade Group = 1; n = 139) and intermediate/high-grade (ISUP Grade Group ≥ 2; n = 108). Volatile organic compounds (VOCs) in urine were extracted by stir bar sorptive extraction (SBSE) and analyzed using thermal desorption with gas chromatography and mass spectrometry (GC-MS). We used machine learning tools to develop and evaluate models for PCa diagnosis and prognosis. In total, 22,538 VOCs were identified in the urine samples. With regularized logistic regression, our model for PCa diagnosis yielded an area under the curve (AUC) of 0.99 and 0.88 for the training and testing sets respectively. Furthermore, the model for differentiating between low-grade and intermediate/high-grade PCa yielded an average AUC of 0.78 based on a repeated test-sample approach for cross-validation. These novel methods using urinary VOCs and logistic regression were developed to fill gaps in PCa screening and assessment of PCa grades prior to biopsy. Our study findings provide a promising alternative or adjunct to current PCa screening and diagnostic methods to better target patients for biopsy and mitigate the challenges associated with over-diagnosis and over-treatment of PCa.

4.
Am J Clin Exp Urol ; 11(6): 481-499, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38148934

RESUMO

BACKGROUND: Cancer detection presents challenges regarding invasiveness, cost, and reliability. As a result, exploring alternative diagnostic methods holds significant clinical importance. Urinary metabolomic profiling has emerged as a promising avenue; however, its application for cancer diagnosis may be influenced by sample preparation or storage conditions. OBJECTIVE: This study aimed to assess the impact of sample storage and processing conditions on urinary volatile organic compounds (VOCs) profiles and establish a robust standard operating procedure (SOP) for such diagnostic applications. METHODS: Five key variables were investigated: storage temperatures, durations, freeze-thaw cycles, sample collection conditions, and sample amounts. The analysis of VOCs involved stir bar sorptive extraction coupled with thermal desorption-gas chromatography/mass spectrometry (SBSE-TD-GC-MS), with compound identification facilitated by the National Institute of Standards and Technology Library (NIST). Extensive statistical analysis, including combined scatterplot and response surface (CSRS) plots, partial least squares-discriminant analysis (PLS-DA), and probability density function plots (PDFs), were employed to study the effects of the factors. RESULTS: Our findings revealed that urine storage duration, sample amount, temperature, and fasting/non-fasting sample collection did not significantly impact urinary metabolite profiles. This suggests flexibility in urine sample collection conditions, enabling individuals to contribute samples under varying circumstances. However, the influence of freeze-thaw cycles was evident, as VOC profiles exhibited distinct clustering patterns based on the number of cycles. This emphasizes the effect of freeze-thaw cycles on the integrity of urinary profiles. CONCLUSIONS: The developed SOP integrating SBSE-TD-GC-MS and statistical analyses can serve as a valuable tool for analyzing urinary organic compounds with minimal preparation and sensitive detection. The findings also support that urinary VOCs for cancer screening and diagnosis could be a feasible alternative offering a robust, non-invasive, and sensitive approach for cancer screening.

5.
Chemosphere ; 338: 139439, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37429381

RESUMO

Fluorotelomer alcohols (FTOHs) are one of the major classes of per- and polyfluoroalkyl substances (PFAS). Due to their potential toxicity, persistence, and ubiquitous presence in the environment, some common PFAS are voluntarily phased out; while FTOHs are used as alternatives to conventional PFAS. FTOHs are precursors of perfluorocarboxylic acids (PFCAs) and therefore they are commonly detected in water matrices, which eventually indicate PFAS contamination in drinking water supplies and thus a potential source of human exposure. Even though studies have been conducted nationwide to evaluate the degree of FTOHs in the water environment, robust monitoring is lacking because of the unavailability of simple and sustainable analytical extraction and detection methods. To fill the gap, we developed and validated a simple, rapid, minimal solvent use, no clean-up, and sensitive method for the determination of FTOHs in water by stir bar sorptive extraction (SBSE) coupled with thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS). Three commonly detected FTOHs (6:2 FTOH, 8:2 FTOH, and 10:2 FTOH) were selected as the model compounds. Factors such as extraction time, stirring speed, solvent composition, salt addition, and pH were investigated to achieve optimal extraction efficiency. This "green chemistry" based extraction provided good sensitivity and precision with low method limits of detection ranging from 2.16 ng/L to 16.7 ng/L and with an extraction recovery ranging 55%-111%. The developed method were tested on tap water, brackish water, and wastewater influent and effluent. 6:2 FTOH and 8:2 FTOH were detected in two wastewater samples at 78.0 and 34.8 ng/L, respectively. This optimized SBSE-TD-GC-MS method will be a valuable alternative to investigate FTOHs in water matrices.


Assuntos
Fluorocarbonos , Poluentes Químicos da Água , Humanos , Águas Residuárias , Fluorocarbonos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Solventes/análise , Poluentes Químicos da Água/análise , Reprodutibilidade dos Testes
6.
Plant Genome ; 16(3): e20348, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37194434

RESUMO

A weak codon usage bias was found in Dendrobium catenatum (D. officiale) antimicrobial peptides (AMPs), after the analysis of relative synonymous codon usage, GC contents, and the effective number of codons. The codon usage preference was mainly influenced by natural selection pressure. The self-optimized prediction method and SWISS-MODEL were applied for peptide structural and domain analyses, and some typical antimicrobial domains were found in D. officinale AMP amino sequences, such as knot1 domain, gibberellins-stimulated domain, cupin_1 domain, defensin_like domain, and SLR1-BP (S locus-related glycoprotein 1 binding pollen coat protein) domain. To investigate the AMPs gene expression pattern, abiotic stresses, such as salt stress, drought stress, salicylic acid (SA), and methyl jasmonate (JA), were applied and the gene expression levels were detected by the real-time fluorescent quantitative polymerase chain reaction. Results showed that, even though the basic AMPs gene expressions were low, some AMPs can still be induced by salt dress, while the drought dress did not show the same impact. The SA and JA signaling pathways might be involved in most of the AMPs expressions. The natural selection of the D. officinale AMPs and thus forming diverse types of AMPs enhanced the plant's innate immunity and disease resistance capability, which would lead to a better understanding of the molecular mechanism for D. officinale adapting to the environment. The finding that salt stress, SA, and JA signaling pathways can induce AMP expression lays a foundation for the further development and functional verification of D. officinale AMPs.


Assuntos
Dendrobium , Dendrobium/genética , Dendrobium/metabolismo , Peptídeos Antimicrobianos , Genes de Plantas , Genômica , Ácido Salicílico/metabolismo , Expressão Gênica
7.
Biomolecules ; 13(5)2023 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-37238639

RESUMO

The oral route is considered the most convenient route of drug administration for both systemic and local delivery. Besides stability and transportation, another unmet but important issue regarding oral medication is retention duration within the specific region of the gastrointestinal (GI) tract. We hypothesize that an oral vehicle that can adhere and maintain retention within the stomach for a longer duration can be more effective to treat stomach-related diseases. Therefore, in this project, we developed a carrier that is highly specific to the stomach and maintains its retention for a longer duration. We developed a vehicle composed of ß-Glucan And Docosahexaenoic Acid (GADA) to observe its affinity and specificity to the stomach. GADA forms a spherical-shaped particle with negative zeta potential values that vary based on the feed ratio of docosahexaenoic acid. Docosahexaenoic acid is an omega-3 fatty acid that has transporters and receptors throughout the GI tract, such as CD36, plasma membrane-associated fatty acid-binding protein (FABP (pm)), and a family of fatty acid transport proteins (FATP1-6). The in vitro studies and characterization data showed that GADA has the capability to carry a payload of hydrophobic molecules and specifically deliver the payload to the GI tract, exert its therapeutic effects, and help to maintain stability for more than 12 h in the gastric and intestinal fluid. The particle size and surface plasmon resonance (SPR) data showed that GADA has a strong binding affinity with mucin in the presence of simulated gastric fluids. We observed a comparatively higher drug release of lidocaine in gastric juice than that in intestinal fluids, demonstrating the influence of the pH values of the media on drug-release kinetics. In vivo and ex vivo imaging of mice demonstrated that GADA maintains its retention within the stomach for at least 4 hr. This stomach-specific oral vehicle holds strong promise to translate various injectable therapeutic drugs to oral form upon further optimizations.


Assuntos
Ácidos Graxos , beta-Glucanas , Camundongos , Animais , Ácidos Docosa-Hexaenoicos , Sistemas de Liberação de Medicamentos , Trato Gastrointestinal , Portadores de Fármacos/química
8.
Sci Total Environ ; 844: 157160, 2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-35798116

RESUMO

The objective of the current study is to evaluate both the positive and negative effects of manganese-doped graphene quantum dots (GQD-Mn) on Capsicum annuum L. grown under salt stress. GQD-Mn was synthesized, characterized, and foliar-applied (250 mg/L, 120 mg/L, 60 mg/L) to C. annuum L. before and after the flowering stage, during which 100 mM of NaCl solution was introduced into the soil as salt stress. Controls were designed as absolute control (no nanomaterials or salt) and negative control (no nanomaterials only salt). Herein, we report that GQD-Mn offset the reduction of fruit production in salt-stressed C. annuum L. by around 40 %. However, based on a comprehensive analysis of normal alkanes (n-alkane) using gas chromatography-mass spectrometry (GC-MS), we also observed that the leaf epicuticular wax profile was disturbed by GQD-Mn, as the concentration of long-chain n-alkanes was increased. Meanwhile, the content of magnesium (Mg) and zinc (Zn) indicated a potential promoted photosynthesis activity in C. annuum L leaves. We hypothesize that the optical properties of GQD-Mn allow leaves to utilize light more efficiently, thus improving photosynthetic activities in plants to acclimate salt stress. But the increased light usage also induced heat stress on the leaf surfaces, which caused n-alkanes changes. Our results provided a unique perspective on nano-plant interaction that value both beneficial and toxic effects of nanomaterials, especially when evaluating the safety of nano-enabled agriculture in areas facing harsh environmental conditions such as salinity.


Assuntos
Capsicum , Grafite , Pontos Quânticos , Alcanos , Capsicum/química , Íons , Manganês/toxicidade , Folhas de Planta , Pontos Quânticos/toxicidade , Estresse Salino
9.
Ecotoxicol Environ Saf ; 241: 113800, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35751931

RESUMO

Through the applications of recycling sewage sludge to soils as nutrients, bisphenol A (BPA) and titanium dioxide nanoparticles (TiO2-NPs) are commonly found in the agricultural environment. Previous studies have reported that BPA and nanoparticles are harmful to the environment. However, the combined toxicity of both compounds is not yet understood. This work presented an in-depth proteomic analysis of Arabidopsis thaliana exposed to BPA and TiO2-NPs concurrently at environmentally relevant levels. Seeds were simultaneously treated with varying concentrations of BPA (0, 10, 100, and 1000 µg·kg-1) and TiO2-NPs (0, 1, 10 and 100 mg·kg-1). In treatment of 1000 µg·kg-1 BPA and 100 mg·kg-1 TiO2-NPs, highest seed germination rate (87.97%, p < 0.05) was observed. Shorter primary roots but more branched roots were obtained in treatments of high BPA and NPs concentrations (100, 1000 µg·kg-1 BPA and 10, 100 mg·kg-1 TiO2-NPs) while no significant effects on plant height and biomass were found. In the comparative analysis, both concentration related positive and negative effects were observed, such as regulation of cell proliferation (positive), root hair elongation (positive), cellular response to oxidative stress (negative), and cell wall organization (negative). In response to the stress caused by BPA and TiO2-NPs, some proteins related to plant root development, such as CD48E, DNAJ2 and GL24, were up-regulated explaining the shorter primary root length and more branched roots. Moreover, Arabidopsis may have stimulated its ability of resource transportation and energy metabolism to overcome the stress and maintain or somehow enhance their growth by up-regulating proteins like TBB6, CALM1, RAA2A, G3PP2 and KASC1. Our comparative proteomics analysis also highlighted multiple biological processes that consequently lead to the stability of plant growth and its stress adaptation. The results demonstrated that applying biosolids to soil as a fertilizer may be considered as a sustainable practice.


Assuntos
Arabidopsis , Nanopartículas , Compostos Benzidrílicos , Fenóis , Proteômica , Esgotos , Solo , Titânio/toxicidade
10.
PLoS One ; 16(2): e0245530, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33596212

RESUMO

Prostate cancer is the second leading cause of cancer death in men in the developed world. A more sensitive and specific detection strategy for lethal prostate cancer beyond serum prostate specific antigen (PSA) population screening is urgently needed. Diagnosis by canine olfaction, using dogs trained to detect cancer by smell, has been shown to be both specific and sensitive. While dogs themselves are impractical as scalable diagnostic sensors, machine olfaction for cancer detection is testable. However, studies bridging the divide between clinical diagnostic techniques, artificial intelligence, and molecular analysis remains difficult due to the significant divide between these disciplines. We tested the clinical feasibility of a cross-disciplinary, integrative approach to early prostate cancer biosensing in urine using trained canine olfaction, volatile organic compound (VOC) analysis by gas chromatography-mass spectroscopy (GC-MS) artificial neural network (ANN)-assisted examination, and microbial profiling in a double-blinded pilot study. Two dogs were trained to detect Gleason 9 prostate cancer in urine collected from biopsy-confirmed patients. Biopsy-negative controls were used to assess canine specificity as prostate cancer biodetectors. Urine samples were simultaneously analyzed for their VOC content in headspace via GC-MS and urinary microbiota content via 16S rDNA Illumina sequencing. In addition, the dogs' diagnoses were used to train an ANN to detect significant peaks in the GC-MS data. The canine olfaction system was 71% sensitive and between 70-76% specific at detecting Gleason 9 prostate cancer. We have also confirmed VOC differences by GC-MS and microbiota differences by 16S rDNA sequencing between cancer positive and biopsy-negative controls. Furthermore, the trained ANN identified regions of interest in the GC-MS data, informed by the canine diagnoses. Methodology and feasibility are established to inform larger-scale studies using canine olfaction, urinary VOCs, and urinary microbiota profiling to develop machine olfaction diagnostic tools. Scalable multi-disciplinary tools may then be compared to PSA screening for earlier, non-invasive, more specific and sensitive detection of clinically aggressive prostate cancers in urine samples.


Assuntos
Biomarcadores Tumorais/urina , Neoplasias da Próstata/diagnóstico , Olfato , Sistema Urinário/microbiologia , Compostos Orgânicos Voláteis/urina , Animais , Cães , Estudos de Viabilidade , Masculino , Projetos Piloto
11.
J Am Chem Soc ; 142(18): 8233-8242, 2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32279486

RESUMO

Room temperature photolysis of the bis(azide)cobaltate(II) complex [Na(THF)x][(ketguan)Co(N3)2] (ketguan = [(tBu2CN)C(NDipp)2]-, Dipp = 2,6-diisopropylphenyl) (3a) in THF cleanly forms the binuclear cobalt nitride Na(THF)4{[(ketguan)Co(N3)]2(µ-N)} (1). Compound 1 represents the first example of an isolable, bimetallic cobalt nitride complex, and it has been fully characterized by spectroscopic, magnetic, and computational analyses. Density functional theory supports a CoIII═N═CoIII canonical form with significant π-bonding between the cobalt centers and the nitride atom. Unlike other group 9 bridging nitride complexes, no radical character is detected at the bridging N atom of 1. Indeed, 1 is unreactive toward weak C-H donors and even cocrystallizes with a molecule of cyclohexadiene (CHD) in its crystallographic unit cell to give 1·CHD as a room temperature stable product. Notably, addition of pyridine to 1 or photolyzed solutions of [(ketguan)Co(N3)(py)]2 (4a) leads to destabilization via activation of the nitride unit, resulting in the mixed-valent Co(II)/Co(III) bridged imido species [(ketguan)Co(py)][(ketguan)Co](µ-NH)(µ-N3) (5) formed from intermolecular hydrogen atom abstraction (HAA) of strong C-H bonds (BDE ∼ 100 kcal/mol). Kinetic rate analysis of the formation of 5 in the presence of C6H12 or C6D12 gives a KIE = 2.5 ± 0.1, supportive of a HAA formation pathway. The reactivity of our system was further probed by photolyzing benzene/pyridine solutions of 4a under H2 and D2 atmospheres (150 psi), which leads to the exclusive formation of the bis(imido) complexes [(ketguan)Co(µ-NH)]2 (6) and [(ketguan)Co(µ-ND)]2 (6-D), respectively, as a result of dihydrogen activation. These results provide unique insights into the chemistry and electronic structure of late 3d metal nitrides while providing entryway into C-H activation pathways.

12.
Chemistry ; 26(13): 2803-2807, 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-31846166

RESUMO

Two electron-reduction of the TiIV guanidinate complex (ImDipp N)(Xyket guan)TiCl2 gives (η6 -ImDipp N)(xyket guan)Ti (1intra ) and (ImDipp N)(Xyket guan)Ti(η6 -C6 H6 ) (1inter ) (Xyket guan=[(tBuC=N)C(NXylyl)2 ]- , Xylyl=2,5-dimethylphenyl) in the absence or presence of benzene, respectively. These complexes have been found to hydrogenate monocyclic and polycyclic arenes under relatively mild conditions (150 psi, 80 °C)-the first example of catalytic, homogeneous arene hydrogenation with TON >1 by a Group IV system.

13.
J Health Pollut ; 9(23): 190912, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31497375

RESUMO

BACKGROUND: The worldwide emergence of multi-drug resistant bacteria has become a health crisis, as fewer or sometimes no antimicrobial agents are effective against these bacteria. The Rio Grande River is the natural boundary between the United States (US) and Mexico. It spans a border region between Texas, New Mexico and Mexico. Underserved populations on the Mexican side use the river for recreational purposes, while on the US side, the river is used for irrigation and as a source of drinking water. OBJECTIVES: The purpose of the present study was to evaluate the concentration of antibiotic residues, to determine the presence of genetic elements conferring antibiotic resistance and to characterize multi-drug resistant bacteria in the waters of the Rio Grande River. METHODS: Water samples were obtained from the Rio Grande River. Deoxyribonucleic acid (DNA) was extracted from both isolated bacteria and directly from the water. Amplification of selected genetic elements was accomplished by polymerase chain reaction. Identification and isolation of bacteria was performed through MicroScan autoSCAN-4. Fecal contamination was assessed by IDEXX Colilert. Antibiotic residues were determined by liquid chromatography and mass spectrometry. RESULTS: Antibiotics were found in 92% of both water and sediment samples. Antibiotic concentrations ranged from 0.38 ng/L - 742.73 ng/L and 0.39 ng/l - 66.3 ng/g dry weight in water and sediment samples, respectively. Genetic elements conferring resistance were recovered from all collection sites. Of the isolated bacteria, 91 (64.08%) were resistant to at least two synergistic antibiotic combinations and 11 (14.79%) were found to be resistant to 20 or more individual antibiotics. Fecal contamination was higher during the months of April and July. CONCLUSIONS: The 26 km segment of the Rio Grande River from Sunland Park NM to El Paso, TX and Juarez, Mexico is an area of concern due to poor water quality. The presence of multidrug resistant bacteria, antibiotics and mobile genetic elements may be a health hazard for the surrounding populations of this binational border region. Policies need to be developed for the appropriate management of the environmental natural resources in this border region. COMPETING INTERESTS: The authors declare no competing financial interests.

14.
Am J Clin Exp Urol ; 7(4): 232-248, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31511830

RESUMO

Cancer is one of the most devastating human diseases that causes a great number of mortalities each year worldwide. Thus, finding and treating cancers early is of increasing interest to the public and presents great opportunity for research. It is well known that the metabolism of cancer cells differs from that of normal tissues. Analysis of volatile organic compounds (VOCs), a group of small molecule metabolites, provides an emerging approach for cancer screening and disease monitoring. VOCs are continuously generated in human body and released through breath, blood, skin, urine and fecal samples, which carry information of the physiological and metabolic status. Furthermore, the development of effective analytical methods for VOCs detection is one of the challenging aspects in cancer research. In this review, the analytical methods such as solid-phase mirco-extraction (SPME) and stir bar sorptive extraction (SBSE) coupled with gas chromatography/mass spectrometry (GC-MS), the application of VOCs in urological cancers diagnosis and potential molecules pathways related to VOCs profile for cancer detection are discussed.

15.
Clin Genitourin Cancer ; 17(3): 183-190, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30853355

RESUMO

BACKGROUND: Prostate cancer (PCa) screening using serum prostate-specific antigen (PSA) testing has caused unnecessary biopsies and overdiagnosis owing to its low accuracy and reliability. Therefore, there is an increased interest in identifying better PCa biomarkers. Studies showed that trained dogs can discriminate patients with PCa from unaffected men by sniffing urine. We hypothesized that urinary volatile organic compounds (VOCs) may be the source of that odor and could be used to develop urinary VOC PCa diagnosis models. PATIENTS AND METHODS: Urine samples from 55 and 53 biopsy proven PCa-positive and -negative patients respectively were initially obtained for diagnostic model development. Urinary metabolites were analyzed by gas chromatography-mass spectrometry. A PCa diagnosis model was developed and validated using innovative statistical machine-learning techniques. A second set of samples (53 PCa-positive and 22 PCa-negative patients) were used to evaluate the previously developed PCa diagnosis model. RESULTS: The analysis resulted in 254 and 282 VOCs for their significant association (P < .05) with either PCa-positive or -negative samples respectively. Regularized logistic regression analysis and the Firth method were then applied to predict PCa prevalence, resulting in a final model that contains 11 VOCs. Under cross-validation, the area under the receiver operating characteristic curve (AUC) for the final model was 0.92 (sensitivity, 0.96; specificity, 0.80). Further evaluation of the developed model using a testing cohort yielded an AUC of 0.86. As a comparison, the PSA-based diagnosis model only rendered an AUC of 0.54. CONCLUSION: The study describes the development of a urinary VOC-based model for PCa detection.


Assuntos
Biomarcadores Tumorais/urina , Metabolômica/métodos , Neoplasias da Próstata/diagnóstico , Compostos Orgânicos Voláteis/urina , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Modelos Logísticos , Aprendizado de Máquina , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/urina , Curva ROC , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
16.
Environ Sci Pollut Res Int ; 25(18): 17227-17239, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29808400

RESUMO

There are eight bisphenol analogues being identified and characterized; among them, bisphenol A (BPA) is on the priority list on the basis of its higher level of uses, occurrence, and toxicity. The endocrine system interfered by BPA has been inventoried as it has the same function as the natural hormone 17ß-estradiol and binds mainly to the estrogen receptor (ER) to exhibit estrogenic activities. The BPA concentration in surface waters (14-1390 ng/L) in many parts of the world, such as Japan, Korea, China, and India, was also a significant concern. Research efforts are focusing on restricting BPA consumption as well as removing BPA in our environment especially in drinking water. Current opinion is that lignocellulosic activated carbon stimulated with BPA-degrading bacteria could have the potential to provide solution for recent challenges faced by water utilities arising from BPA contamination in water. This technology has some new trends in the low-cost biofiltration process for removing BPA. This review is to provide in-depth discussion on the fate of BPA in our ecosystem and underlines methods to enhance the efficacy of activated carbon in the presence of BPA-degrading bacteria in the biofiltration process.


Assuntos
Compostos Benzidrílicos/química , Carvão Vegetal/química , Estradiol/metabolismo , Fenóis/química , Receptores de Estrogênio/metabolismo , Bactérias/metabolismo , China , Estradiol/química , Índia , Japão , Receptores de Estrogênio/química , República da Coreia
17.
J Agric Food Chem ; 66(13): 3358-3366, 2018 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-29558120

RESUMO

In this study, low and high anthocyanin basil ( Ocimum basilicum) varieties (LAV and HAV) were sprayed with 4.8 mg Cu/per pot from Cu(OH)2 nanowires, Cu(OH)2 bulk (CuPro), or CuSO4 and cultivated for 45 days. In both varieties, significantly higher Cu was determined in leaves of CuSO4 exposed plants (691 and 672.6 mg/kg for LAV and HAV, respectively); however, only in roots of HAV, Cu was higher, compared to control ( p ≤ 0.05). Nanowires increased n-decanoic, dodecanoic, octanoic, and nonanoic acids in LAV, but reduced n-decanoic, dodecanoic, octanoic, and tetradecanoic acids in HAV, compared with control. In HAV, all compounds reduced eugenol (87%), 2-methylundecanal (71%), and anthocyanin (3%) ( p ≤ 0.05). In addition, in all plant tissues, of both varieties, nanowires and CuSO4 reduced Mn, while CuPro increased chlorophyll contents, compared with controls ( p ≤ 0.05). Results suggest that the effects of Cu(OH)2 pesticides are variety- and compound-dependent.


Assuntos
Cobre/farmacologia , Hidróxidos/farmacologia , Ocimum basilicum/efeitos dos fármacos , Antocianinas/análise , Antocianinas/metabolismo , Clorofila/análise , Clorofila/metabolismo , Cobre/análise , Cobre/metabolismo , Hidróxidos/análise , Hidróxidos/metabolismo , Ocimum basilicum/química , Ocimum basilicum/metabolismo , Folhas de Planta/química , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo
18.
Water Sci Technol ; 73(2): 302-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26819385

RESUMO

A mass loading and mass balance analysis was performed on selected polybromodiphenyl ethers (PBDEs) in the first full-scale indirect potable reuse treatment plant in the United States. Chemical analysis of PBDEs was performed using an environmentally friendly sample preparation technique, called stir-bar sorptive extraction (SBSE), coupled with thermal desorption and gas chromatography/mass spectrometry (GC/MS). The three most dominant PBDEs found in all the samples were: BDE-47, BDE-99 and BDE-100. In the wastewater influent, the concentrations of studied PBDEs ranged from 94 to 775 ng/L, and in the effluent, the levels were below the detection limit. Concentrations in sludge ranged from 50 to 182 ng/g. In general, a removal efficiency of 92-96% of the PBDEs in the plant was accomplished through primary and secondary processes. The tertiary treatment process was able to effectively reduce the aforementioned PBDEs to less than 10 ng/L (>96% removal efficiency) in the effluent. If PBDEs remain in the treated wastewater effluent, they may pose environmental and health impacts through aquifer recharge, irrigation, and sludge final disposal.


Assuntos
Éteres Difenil Halogenados/análise , Bifenil Polibromatos/análise , Águas Residuárias/química , Poluentes Químicos da Água/análise , Cromatografia Gasosa-Espectrometria de Massas , Esgotos/química
19.
J Agric Food Chem ; 61(47): 11278-85, 2013 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-24188281

RESUMO

Despite the remarkable number of publications on the interaction of engineered nanoparticles (ENPs) with plants, knowledge of the implications of ENPs in the nutritional value of food crops is still limited. This research was performed to study the quality of rice grains harvested from plants grown in soil treated with cerium oxide nanoparticles (nCeO2). Three rice varieties (high, medium, and low amylose) were cultivated to full maturity in soil amended with nCeO2 at 0 and 500 mg kg(-1) soil. Ce accumulation, nutrient content, antioxidant property, and nutritional quality of the rice grains were evaluated. Results showed that rice grains from nCeO2-treated plants had less Fe, S, prolamin, glutelin, lauric and valeric acids, and starch. Moreover, the nCeO2 reduced in grains all antioxidant values, except flavonoids. Medium- and low-amylose varieties accumulated more Ce in grains than the high-amylose variety, but the grain quality of the medium-amylose variety showed higher sensitivity to the nCeO2 treatment. These results indicate that nCeO2 could compromise the quality of rice. To the authors' knowledge, this is the first report on the effects nCeO2 on rice grain quality.


Assuntos
Cério/farmacologia , Qualidade dos Alimentos , Nanopartículas , Valor Nutritivo , Oryza/química , Oryza/efeitos dos fármacos , Antioxidantes/metabolismo , Cério/farmacocinética , Ácidos Graxos/análise , Ácidos Graxos/metabolismo , Glutens/análise , Glutens/metabolismo , Ácidos Láuricos/análise , Ácidos Láuricos/metabolismo , Oryza/metabolismo , Ácidos Pentanoicos/análise , Ácidos Pentanoicos/metabolismo , Proteínas de Plantas/análise , Proteínas de Plantas/metabolismo , Prolaminas/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Amido/análise
20.
Environ Sci Technol ; 47(24): 14110-8, 2013 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-24266714

RESUMO

Cerium oxide nanoparticles (nCeO2) have been shown to have significant interactions in plants; however, there are limited reports on their impacts in rice (Oryza sativa). Given the widespread environmental dispersal of nCeO2, it is paramount to understand its biochemical and molecular impacts on a globally important agricultural crop, such as rice. This study was carried out to determine the impact of nCeO2 on the oxidative stress, membrane damage, antioxidant enzymes' activities, and macromolecular changes in the roots of rice seedlings. Rice seeds (medium amylose) were grown for 10 days in nCeO2 suspensions (0-500 mg L(-1)). Results showed that Ce in root seedlings increased as the external nCeO2 increased without visible signs of toxicity. Relative to the control, the 62.5 mg nCeO2 L(-1) reduced the H2O2 generation in the roots by 75%. At 125 mg nCeO2 L(-1), the roots showed enhanced lipid peroxidation and electrolyte leakage, while at 500 mg L(-1), the nCeO2 increased the H2O2 generation in roots and reduced the fatty acid content. The lignin content decreased by 20% at 500 mg nCeO2 L(-1), despite the parallel increase in H2O2 content and peroxidase activities. Synchrotron µ-XRF confirmed the presence of Ce in the vascular tissues of the roots.


Assuntos
Cério/química , Substâncias Macromoleculares/metabolismo , Nanopartículas/química , Oryza/enzimologia , Estresse Oxidativo , Plântula/enzimologia , Estresse Fisiológico , Amilose/metabolismo , Antioxidantes/metabolismo , Cério/metabolismo , Eletrólitos/metabolismo , Ácidos Graxos/metabolismo , Peróxido de Hidrogênio/análise , Peróxido de Hidrogênio/metabolismo , Lignina/metabolismo , Peroxidação de Lipídeos , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Oxirredução , Raízes de Plantas/enzimologia , Plântula/metabolismo , Espectrometria por Raios X , Síncrotrons , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
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