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1.
Biochem Cell Biol ; 102(2): 194-205, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37948675

RESUMO

Increasing evidence of sperm RNA's role in fertilization and embryonic development has provided impetus for its isolation and thorough characterization. Sperm are considered tough-to-lyse cells due to the compact condensed DNA in sperm heads. Lack of consensus among bovine sperm RNA isolation protocols introduces experimental variability in transcriptome studies. Here, we describe an optimized method for total RNA isolation from bovine sperm using the TRIzol reagent. This study critically investigated the effects of various lysis conditions on sperm RNA isolation. Sperm suspended in TRIzol were subjected to a combination of mechanical treatments (sonication and passage through a 30G needle and syringe) and chemical treatments (supplementation with reducing agents 1,4-dithiothreitol and tris(2-carboxyethyl) phosphine hydrochloride (TCEP)). Microscopic evaluation of sperm lysis confirmed preferential sperm tail versus sperm head lysis. Interestingly, only TCEP-supplemented TRIzol (both mechanical treatments) had progressive sperm head lysis and consistently yielded total sperm RNA. Furthermore, RNA integrity was confirmed based on the electrophoresis profile and an absence of genomic DNA and somatic cells (e.g., epithelial cells, spermatids, etc.) with RT-qPCR. Our findings highlighted the importance of sperm lysis, specifically of the sperm head using TCEP with mechanical treatment, in total RNA isolation and presented a bovine-specific sperm RNA isolation method to reduce experimental variabilities.


Assuntos
Guanidinas , Fenóis , Fosfinas , Sêmen , Espermatozoides , Masculino , Animais , Bovinos , Espermatozoides/química , Cabeça do Espermatozoide , RNA/análise , DNA
2.
Biochem Biophys Res Commun ; 700: 149608, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38306932

RESUMO

ß-glucosidases (Bgls) are glycosyl hydrolases that catalyze the conversion of cellobiose or glucosyl-polysaccharide into glucose. Bgls are widely used in industry to produce bioethanol, wine and juice, and feed. Tris (tris(hydroxymethyl)aminomethane) is an organic compound that can inhibit the hydrolase activity of some Bgls, but the inhibition state and selectivity have not been fully elucidated. Here, three crystal structures of Thermoanaerobacterium saccharolyticum Bgl complexed with the Tris molecule were determined at 1.55-1.95 Å. The configuration of Tris binding to TsaBgl remained consistent across three crystal structures, and the amino acids interacting with the Tris molecule were conserved across Bgl enzymes. The positions O1 and O3 atoms of Tris exhibit the same binding moiety as the hydroxyl group of the glucose molecule. Tris molecules are stably positioned at the glycone site and coordinate with surrounding water molecules. The Tris-binding configuration of TsaBgl is similar to that of HjeBgl, HgaBgl, ManBgl, and KflBgl, but the arrangement of the water molecule coordinating Tris at the aglycone site differs. Meanwhile, both the arrangement of Tris and the water molecules in ubBgl, NkoBgl, and SfrBgl differ from those in TsaBgl. The binding configuration and affinity of the Tris molecule for Bgl may be affected by the residues on the aglycone and gatekeeper regions. This result will extend our knowledge of the inhibitory effect of Tris molecules on TsaBgl.


Assuntos
Celobiose , beta-Glucosidase , beta-Glucosidase/metabolismo , Celobiose/metabolismo , Glucose/metabolismo , Catálise , Água
3.
Small ; 20(25): e2309871, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38299765

RESUMO

Owing to the outstanding comprehensive properties of high energy density, excellent cycling ability, and reasonable cost, Ni-rich layered oxides (NCM) are the most promising cathode for lithium-ion batteries (LIBs). To further enhance the specific capacity of Ni-rich layered oxides, it is necessary to increase the cut-off voltage to a higher level. However, a higher cut-off voltage can lead to substantial structural changes and trigger interface side reactions, presenting significant challenges for practical applications (cycle life and safety). Herein, to solve above issues, tris(hexafluoroisopropyl)borate (TFPB) is introduced as a high voltage electrolyte additive for LiNi0.90Co0.06Mn0.04O2 cathode. Based on detail in situ/ex situ characterization, this study proves that TFPB forms a protective solid-state interphase (SEI) layer on the Li-anode. Additionally, derivatives of TFPB are easily oxidatively decomposed to create a dense cathode electrolyte interphase (CEI) film on the cathode. This CEI film effectively prevents the continuous oxidation of the electrolyte and mitigates the adverse effects of HF on the battery. Benefit from the protective SEI and CEI layer, the LiNi0.90Co0.06Mn0.04O2||Li battery with a TFPB-containing electrolyte maintains an unprecedented level of performance, with a capacity retention of 89.1% after 100 cycles under the ultrahigh cut-off voltage of 4.6 V (vs Li/Li+).

4.
Chemistry ; 30(6): e202302256, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-37922225

RESUMO

A complete theoretical analysis using first the simple Hückel model followed by more sophisticated multi-reference calculations on a trinuclear Ni(II) complex (Tp#Ni3 HHTP), bearing the non-innocent bridging ligand HHTP3- , is carried out. The three semiquinone moieties of HHTP3- couple antiferromagnetically and lead to a single unpaired electron localized on one of the moieties. The calculated exchange coupling integrals together with the zero-field parameters allow, when varied within a certain range, reproducing the experimental data. These results are generalized for two similar other trinuclear complexes containing Ni(II) and Cu(II). The electronic structure of HHTP3- turns out to be independent of both the chemical nature and the geometry of the metal ions. We also establish a direct correlation between the geometrical and the electronic structures of the non-innocent ligand that is consistent with the results of calculations. It allows experimentalists to get insight into the magnetic behavior of this type of complexes by an analysis of their X-ray structure.

5.
Chemistry ; 30(2): e202302943, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-37803935

RESUMO

Excellent stability is an essential premise for organic diradicals to be used in organic electronic and spintronic devices. We have attached two tris(2,4,6-trichlorophenyl)methyl (TTM) radical building blocks to the two sides of perylene bisimide (PBI) bridges and obtained two regioisomeric diradicals (1,6-TTM-PBI and 1,7-TTM-PBI). Both of the isomers show super stability rather than the monomeric TTM under ambient conditions, due to the increased conjugation and the electron-withdrawing effects of the PBI bridges. The diradicals show distinct and reversible multistep redox processes, and a spectro-electrochemistry investigation revealed the generation of organic mixed-valence (MV) species during reduction processes. The two diradicals have singlet ground states, very small singlet-triplet energy gaps (ΔES-T ) and a pure open-shell character (with diradical character y0 =0.966 for 1,6-TTM-PBI and 0.967 for 1,7-TTM-PBI). This work opens a window to developing very stable diradicals and offers the opportunity of their further application in optical, electronic and magnetic devices.

6.
Chemistry ; 30(3): e202303151, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-37875461

RESUMO

Initiated by triarylamine radical cation salt (TBPA), the direct C-H bond functionalization of α-N-aryltetrahydroisoquinoline esters was smoothly realized, giving a series of α-hydroxylated derivatives with a quaternary carbon center in good yields. Differently, in the presence of tert-butyl nitrite (TBN), the C-N single bond was cleaved to keto esters. The mechanistic study revealed that these reactions were mediated by a similar mechanism, in which the N-nitrosation might provide a driving force to the C-N bond cleavage.

7.
Chemistry ; 30(18): e202303741, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38206884

RESUMO

Compared with Li+, Na+ with a smaller stokes radius has faster de-solvation kinetics. An electrolyte with ultralow sodium salt (0.3 M NaPF6) is used to reduce the cell cost. However, the organic-dominated interface, mainly derived from decomposed solvents (SSIP solvation structure), is defective for the long cycling performance of sodium ion batteries. In this work, the simple application of dual additives, including sodium difluoro(oxalato)borate (NaDFOB) and tris(trimethylsilyl)borate (TMSB), is demonstrated to improve the cycling performance of the hard carbon/NaNi1/3Fe1/3Mn1/3O2 cell by constructing interface films on the anode and cathode. A significant improvement on cycling stability has been achieved by incorporating dual additives of NaDFOB and TMSB. Particularly, the capacity retention increased from 17 % (baseline) to 79 % (w/w, 2.0 wt % NaDFOB) and 83 % (w/w, 2.0 wt % NaDFOB and 1.0 wt % TMSB) after 200 cycles at room temperature. Insight into the mechanism of improved interfacial properties between electrodes and electrolyte in ultralow concentration electrolyte has been investigated through a combination of theoretical computation and experimental techniques.

8.
Chemphyschem ; : e202400242, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38818637

RESUMO

Tris(trimethylsilyl)amine (N(SiMe3)3) is one of the most important intermediate products in the indirect synthesis of ammonia (NH3) from nitrogen (N2), which could be hydrolyzed to NH3 under mild conditions. Herein, the hydrolysis mechanism of N(SiMe3)3 has been systematically investigated using density functional theory (DFT) with explicit combined implicit water models. Under neutral conditions, the active barrier of the hydrolysis of N(SiMe3)3 is 17.6 kcal mol-1 in water solvent. The attacking of proton to N center and OH group to the Si atom from water is decoupled for the stabilization of OH group by solvent water molecules, which lower the hydrolysis energy barriers. Furthermore, under acid conditions, N(SiMe3)3 is easily coordinated with proton to form [NH(SiMe3)3]+, and the energy barrier of the hydrolysis reaction could be reduced to 11.5 kcal mol-1 of the first stage, making it being promoted according to the chemical equilibrium. Thus, the results provide an explanation for the possible mechanism of the quantitative conversion of N(SiMe3)3 to NH3 under mild conditions. The decoupled hydrolysis mechanism may play important role in other hydrolysis processes.

9.
Mol Pharm ; 21(2): 822-830, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38173242

RESUMO

Titanium-45 (45Ti) is a radionuclide with excellent physical characteristics for use in positron emission tomography (PET) imaging, including a moderate half-life (3.08 h), decay by positron emission (85%), and a low mean positron energy of 0.439 MeV. However, challenges associated with titanium chemistry have led to the underdevelopment of this radionuclide for incorporation into radiopharmaceuticals. Expanding on our recent studies, which showed promising results for the complexation of 45Ti with the tris hydroxypyridinone (THPMe) chelator, the current work aimed to optimize the chemistry and imaging attributes of [45Ti]Ti-THP-PSMA as a new PET radiopharmaceutical. Methods. Radiolabeling of THP-PSMA was optimized with [45Ti]Ti-citrate at varying pHs and masses of the precursor. The stability of the radiolabeled complex was assessed in mouse serum for up to 6 h. The affinity of [45Ti]Ti-THP-PSMA for prostate-specific membrane antigen (PSMA) was assessed using LNCaP (PSMA +) and PC3 (PSMA -) cell lines. In vivo imaging and biodistribution analysis were performed in tumor-bearing xenograft mouse models to confirm the specificity of the tumor uptake. Results. > 95% of radiolabeling was achieved with a high specific activity of 5.6 MBq/nmol under mild conditions. In vitro cell binding studies showed significant binding of the radiolabeled complex with the PSMA-expressing LNCaP cell line (11.9 ± 1.5%/mg protein-bound activity) compared to that with the nonexpressing PC3 cells (1.9 ± 0.4%/mg protein-bound activity). In vivo imaging and biodistribution studies confirmed specific uptake in LNCaP tumors (1.6 ± 0.27% ID/g) compared to that in PC3 tumors (0.39 ± 0.2% ID/g). Conclusion. This study showed a simple one-step radiolabeling method for 45Ti with THP-PSMA under mild conditions (pH 8 and 37 °C). In vitro cell studies showed promise, but in vivo tumor xenograft studies indicated low tumor uptake. Overall, this study shows the need for more chelators for 45Ti for the development of a PET radiopharmaceutical for cancer imaging.


Assuntos
Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias da Próstata , Masculino , Humanos , Animais , Camundongos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Compostos Radiofarmacêuticos , Neoplasias da Próstata/metabolismo , Radioquímica , Distribuição Tecidual , Titânio , Glutamato Carboxipeptidase II/metabolismo , Antígenos de Superfície/metabolismo , Tomografia por Emissão de Pósitrons , Radioisótopos , Quelantes , Linhagem Celular Tumoral
10.
Eur Biophys J ; 53(4): 225-238, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38613566

RESUMO

Calibration of titration calorimeters is an ongoing problem, particularly with calorimeters with reaction vessel volumes < 10 mL in which an electrical calibration heater is positioned outside the calorimetric vessel. Consequently, a chemical reaction with a known enthalpy change must be used to accurately calibrate these calorimeters. This work proposes the use of standard solutions of potassium acid phthalate (KHP) titrated into solutions of excess sodium hydroxide (NaOH) or excess tris(hydroxymethyl)aminomethane (TRIS) as standard reactions to determine the collective accuracy of the relevant variables in a determination of the molar enthalpy change for a reaction. KHP is readily available in high purity, weighable for easy preparation of solutions with accurately known concentrations, stable in solution, not compromised by side reactions with common contaminants such as atmospheric CO2, and non-corrosive to materials used in calorimeter construction. Molar enthalpy changes for these reactions were calculated from 0 to 60 °C from reliable literature data for the pKa of KHP, the molar enthalpy change for protonation of TRIS, and the molar enthalpy change for ionization of water. The feasibility of using these reactions as enthalpic standards was tested in several calorimeters; a 50 mL CSC 4300, a 185 µL NanoITC, a 1.4 mL VP-ITC, and a TAM III with 1 mL reaction vessels. The results from the 50 mL CSC 4300, which was accurately calibrated with an electric heater, verified the accuracy of the calculated standard values for the molar enthalpy changes of the proposed reactions.


Assuntos
Calorimetria , Hidróxido de Sódio , Trometamina , Hidróxido de Sódio/química , Calibragem , Trometamina/química , Temperatura , Padrões de Referência , Termodinâmica
11.
Biometals ; 37(1): 101-113, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37610601

RESUMO

The binding process between three species of chromium and serum albumin (SA) was investigated, as well as the interaction between K2Cr2O7 and bovine serum albumin (BSA) under coexistence of different chromium forms. CrCl3, K2Cr2O7 and Crpic bound to SA spontaneously through Van der Waals force, and their binding constants were 103-104 M-1 at 298 K, respectively. K2Cr2O7 and Crpic both had strong binding affinity for BSA, and significantly affected the secondary structure of BSA and the microenvironment surrounding amino acid residues. Chromium exhibited a greater fluorescence quenching constant towards HSA than toward BSA, and K2Cr2O7 induced greater conformational changes in human serum albumin (HSA) than in BSA. A weak binding of CrCl3 to BSA had no significant effect on the binding affinity of K2Cr2O7 to BSA. K2Cr2O7 and BSA have a greater binding affinity when coexisting with Crpic, and K2Cr2O7 induces a greater conformational change in BSA.


Assuntos
Cromo , Albumina Sérica , Humanos , Albumina Sérica/química , Espectrometria de Fluorescência , Termodinâmica , Soroalbumina Bovina/química , Albumina Sérica Humana/química , Ligação Proteica , Sítios de Ligação , Simulação de Acoplamento Molecular
12.
Environ Res ; 248: 118223, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38286254

RESUMO

Dust is a sink for flame retardants, which are added to a myriad of consumer products in residential spaces. Organophosphate esters (OPEs) and brominated flame retardants (BFRs) are two classes of flame retardants that are frequently used in consumer products and consequently found in dust. In this present work, a novel solvent-limited microextraction technique, which we detailed in a companion study, was applied for the determination of four OPEs and two BFRs with limits of quantitation at the ng/g level by gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry from n = 47 air filter dust samples collected from forced air HVAC systems. Levels of the BFRs, including tetrabromobisphenol-A and its derivative tribromobisphenol-A, were found at levels <4 µg/g and not frequently detected. Conversely, all four OPEs were detected in all air filter dust samples. Total OPE load was dominated by tris(2,4-di-tert-butylphenyl) phosphate, T24DtBPP, a novel OPE not widely examined in the literature. Comparison of individual and total OPE concentrations to residential characteristics revealed statistically significant relationships to location of the home and dominant flooring type. Overall, this study motivates future work in examining the whole house exposome using air filter dust as a passive sampling regime with more examination of T24DtBPP loads within other indoor spaces.


Assuntos
Filtros de Ar , Poluição do Ar em Ambientes Fechados , Expossoma , Retardadores de Chama , Retardadores de Chama/análise , Poeira/análise , Organofosfatos/análise , Poluição do Ar em Ambientes Fechados/análise , Monitoramento Ambiental , Ésteres/análise
13.
BMC Vet Res ; 20(1): 250, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849855

RESUMO

BACKGROUND: Buffalo spermatozoa have a distinct membrane structure that makes them more vulnerable to cryopreservation, resulting in lower-quality post-thawed sperm. This decreases the success rate of artificial insemination in buffaloes. Understanding and addressing these specific vulnerabilities are essential for improving reproductive techniques in buffalo populations. The properties of cryopreserved buffalo bull semen were examined in this study regarding the impact of adding autologous platelet-rich plasma (PRP) to OptiXcell® or Tris egg yolk-based extenders. Ten buffalo bulls were used to collect semen. Each bull's ejaculate was separated into two main equal amounts, each of which was then diluted with either OptiXcell® or Tris egg yolk-based extender, supplemented with various PRP concentrations (5%, 10%, and 15%), and the control (0%), before being cryopreserved according to established protocols. Following equilibration and thawing, the quality and functionality of the sperm were evaluated, along with the antioxidant enzyme activities (GSH and TAC), malondialdehyde (MDA) content, and in vivo fertilization rate of the thawed semen. RESULTS: All PRP concentrations in both extenders, particularly 10% PRP, improved the quality and functionality of the sperm in both equilibrated and frozen-thawed semen. Additionally, the antioxidant enzyme activities in both extenders were higher in the PRP-supplemented groups compared to the control group in thawed semen (P < 0.05). All post-thaw sperm quality, antioxidant enzyme activities, and functionality aside from DNA integrity were higher (P < 0.05) in the PRP-supplemented OptiXcell® than in the PRP-supplemented Tris egg yolk-based extender. The fertility of cryopreserved semen in the extenders supplemented with 10% and 15% PRP increased (P < 0.05) significantly more than that of the control extenders, with 10% PRP being the optimum concentration in OptiXcell® (80%) compared to that of Tris egg yolk-based extender (66.67%) and control of two extenders (53.33% and 46.67%, respectively). CONCLUSIONS: Even though autologous PRP-supplemented extenders have a protective impact on equilibrated and cryopreserved semen, 10% PRP-supplemented OptiXcell® extenders are more effective at preserving post-thaw semen quality, functionality, and antioxidant capacity, which increases the in vivo fertility of buffalo bulls.


Assuntos
Búfalos , Criopreservação , Plasma Rico em Plaquetas , Preservação do Sêmen , Animais , Masculino , Criopreservação/veterinária , Criopreservação/métodos , Preservação do Sêmen/veterinária , Preservação do Sêmen/métodos , Fertilidade , Gema de Ovo/química , Análise do Sêmen/veterinária , Crioprotetores/farmacologia , Inseminação Artificial/veterinária , Feminino , Sêmen , Espermatozoides/fisiologia , Espermatozoides/efeitos dos fármacos
14.
Chirality ; 36(5): e23679, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38752268

RESUMO

Each year, new psychoactive substances appear on the global drug market leading to constant changes. Most of these compounds with stimulating effect possess a chiral center, thus leading to two enantiomers with presumably different pharmacological properties. Among them, synthetic cathinones, often misleadingly traded as "bath salts," play an important role. There is little knowledge about the distinct effect of the enantiomers. The aim of this study was to test a commercially available Lux® i-Amylose-3 column by HPLC-UV for enantiorecognition of cathinone derivatives. Overall, 80 compounds were tested in normal phase mode, where 75 substances were separated under initial conditions. After method optimization, at least partial separation was achieved for the remaining compounds. The same set of substances was measured in polar-organic mode, where 63 analytes were resolved into their enantiomers under initial conditions with very short retention times. Both modes showed complementary results for the individual compounds. Furthermore, the tested methods proved to be suitable for differentiation of positional isomers, which can be useful for drug checking programs. All measurements were carried out under isocratic conditions, and intraday and interday repeatability tests were performed.


Assuntos
Alcaloides , Estereoisomerismo , Cromatografia Líquida de Alta Pressão/métodos , Alcaloides/química , Alcaloides/isolamento & purificação , Amilose/química , Amilose/análogos & derivados , Pirrolidinas
15.
Proc Natl Acad Sci U S A ; 118(39)2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34556577

RESUMO

Proteins achieve efficient energy storage and conversion through electron transfer along a series of redox cofactors. Multiheme cytochromes are notable examples. These proteins transfer electrons over distance scales of several nanometers to >10 µm and in so doing they couple cellular metabolism with extracellular redox partners including electrodes. Here, we report pump-probe spectroscopy that provides a direct measure of the intrinsic rates of heme-heme electron transfer in this fascinating class of proteins. Our study took advantage of a spectrally unique His/Met-ligated heme introduced at a defined site within the decaheme extracellular MtrC protein of Shewanella oneidensis We observed rates of heme-to-heme electron transfer on the order of 109 s-1 (3.7 to 4.3 Å edge-to-edge distance), in good agreement with predictions based on density functional and molecular dynamics calculations. These rates are among the highest reported for ground-state electron transfer in biology. Yet, some fall 2 to 3 orders of magnitude below the Moser-Dutton ruler because electron transfer at these short distances is through space and therefore associated with a higher tunneling barrier than the through-protein tunneling scenario that is usual at longer distances. Moreover, we show that the His/Met-ligated heme creates an electron sink that stabilizes the charge separated state on the 100-µs time scale. This feature could be exploited in future designs of multiheme cytochromes as components of versatile photosynthetic biohybrid assemblies.


Assuntos
Grupo dos Citocromos c/metabolismo , Citocromos/metabolismo , Elétrons , Heme/metabolismo , Histidina/metabolismo , Metionina/metabolismo , Shewanella/metabolismo , Grupo dos Citocromos c/química , Citocromos/química , Transporte de Elétrons , Heme/química , Histidina/química , Metionina/química , Simulação de Dinâmica Molecular , Nanofios , Oxirredução
16.
Ecotoxicol Environ Saf ; 279: 116462, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38776784

RESUMO

Tris (2-ethylhexyl) phosphate (TEHP) is a frequently used organophosphorus flame retardant with significant ecotoxicity and widespread human exposure. Recent research indicates that TEHP has reproductive toxicity. However, the precise cell mechanism is not enough understood. Here, by using testicular mesenchymal stromal TM3 cells as a model, we reveal that TEHP induces apoptosis. Then RNA sequencing analysis, immunofluorescence, and western blotting results show that THEP inhibits autophagy flux and enhances endoplasmic reticulum (ER) stress. Moreover, the activation of the ER stress is critical for TEHP-induced cell injury. Interestingly, TEHP-induced ER stress is contributed to autophagic flux inhibition. Furthermore, pharmacological inhibition of autophagy aggravates, and activation of autophagy attenuates TEHP-induced apoptosis. In summary, these findings indicate that TEHP triggers apoptosis in mouse TM3 cells through ER stress activation and autophagy flux inhibition, offering a new perspective on the mechanisms underlying TEHP-induced interstitial cytotoxicity in the mouse testis.


Assuntos
Apoptose , Autofagia , Estresse do Retículo Endoplasmático , Retardadores de Chama , Células Intersticiais do Testículo , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Animais , Masculino , Células Intersticiais do Testículo/efeitos dos fármacos , Camundongos , Apoptose/efeitos dos fármacos , Retardadores de Chama/toxicidade , Linhagem Celular
17.
Ecotoxicol Environ Saf ; 279: 116469, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38772141

RESUMO

Tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) is a widely used organophosphate ester that can adversely affect animal or human health. The intestinal microbiota is critical to human health. High-dose exposure to TDCIPP can markedly affect the intestinal ecosystem of mice, but the effects of long-term exposure to lower concentrations of TDCIPP on the intestinal flora and body metabolism remain unclear. In this study, TDCIPP was administered to Sprague-Dawley rats by gavage at a dose of 13.3 mg/kg bw/day for 90 days. TDCIPP increased the relative weight of the kidneys (P = 0.017), but had no effect on the relative weight of the heart, liver, spleen, lungs, testes, and ovaries (P > 0.05). 16 S rRNA gene sequencing revealed that long-term TDCIPP exposure affected the diversity, relative abundance, and functions of rat gut microbes. The serum metabolomics of the rats showed that TDCIPP can disrupt the serum metabolic profiles, result in the up-regulation of 26 metabolites and down-regulation of 3 metabolites, and affect multiple metabolic pathways in rat sera. In addition, the disturbed genera and metabolites were correlated. The functions of some disturbed gut microbes were consistent with the affected metabolic pathways in the sera, and these metabolic pathways were all associated with kidney disease, suggesting that TDCIPP may cause kidney injury in rats by affecting the intestinal flora and serum metabolism.


Assuntos
Microbioma Gastrointestinal , Ratos Sprague-Dawley , Animais , Microbioma Gastrointestinal/efeitos dos fármacos , Ratos , Masculino , Feminino , Rim/efeitos dos fármacos , RNA Ribossômico 16S , Compostos Organofosforados
18.
Ecotoxicol Environ Saf ; 270: 115924, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38171103

RESUMO

As a typical organophosphorus flame retardant, tris(2-chloroethyl) phosphate (TCEP) is refractory in aqueous environment. The application of TAP is a promising method for removing pollutants. Herein, the removal of TCEP using TAP was rigorously investigated, and the effects of some key variables were optimized by the one-factor-at-a-time approach. To further evaluate the interactions among variables, the response surface methodology (RSM) based on central composite design was employed. Under optimized conditions (pH 5, [PS]0: [TCEP]0 = 500:1), the maximum removal efficiency (RE) of TCEP reached up to 90.6%. In real-world waters, the RE of TCEP spanned the range of 56%- 65% in river water, pond water, lake water and sanitary sewage. The low-concentration Cl- (0.1 mM) promoted TCEP degradation, but the contrary case occurred when the high-concentration Cl-, NO3-, CO32-, HCO3-, HPO42-, H2PO4-, NH4+ and humic acid were present owing to their prominently quenching effects on SO4•-. Both EPR and scavenger experiments revealed that the main radicals in the TAP system were SO4•- and •OH, in which SO4•- played the most crucial role in TCEP degradation. GC-MS/MS analysis disclosed that two degradation products appeared, sourcing from the replacement, oxidation, hydroxylation and water-molecule elimination reactions. The other two products were inferred from the comprehensive literature. As for acute toxicity to fish, daphnid and green algae, product A displayed the slightly higher toxicity, whereas other three products exhibited the declining toxicity as compared to their parent molecule. These findings offer a theoretical/practical reference for high-efficiency removal of TCEP and its ecotoxicological risk evaluation.


Assuntos
Retardadores de Chama , Fosfinas , Poluentes Químicos da Água , Retardadores de Chama/toxicidade , Espectrometria de Massas em Tandem , Compostos Organofosforados , Organofosfatos/toxicidade , Organofosfatos/química , Oxirredução , Água , Fosfatos , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/química
19.
Toxicol Ind Health ; 40(7): 387-397, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38729922

RESUMO

Tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) is a widely used organophosphorus flame retardant and has been detected in various environmental matrices including indoor dust. Inhalation of indoor dust is one of the most important pathways for human exposure to TDCIPP. However, its adverse effects on human lung cells and potential impacts on respiratory toxicity are largely unknown. In the current study, human non-small cell carcinoma (A549) cells were selected as a cell model, and the effects of TDCIPP on cell viability, cell cycle, cell apoptosis, and underlying molecular mechanisms were investigated. Our data indicated a concentration-dependent decrease in the cell viability of A549 cells after exposure to TDCIPP for 48 h, with half lethal concentration (LC50) being 82.6 µM. In addition, TDCIPP caused cell cycle arrest mainly in the G0/G1 phase by down-regulating the mRNA expression of cyclin D1, CDK4, and CDK6, while up-regulating the mRNA expression of p21 and p27. In addition, cell apoptosis was induced via altering the expression levels of Bcl-2, BAX, and BAK. Our study implies that TDCIPP may pose potential health risks to the human respiratory system and its toxicity should not be neglected.


Assuntos
Apoptose , Sobrevivência Celular , Retardadores de Chama , Compostos Organofosforados , Humanos , Células A549 , Apoptose/efeitos dos fármacos , Retardadores de Chama/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Compostos Organofosforados/toxicidade , Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos
20.
Molecules ; 29(4)2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38398509

RESUMO

The reaction of molybdenum complexes with a tris(pyrazolyl)borate ligand (Et4N[TpMo(CO)3] and Et4N[Tp*Mo(CO)3] (Tp = hydridotris(pyrazolyl)borate, Tp* = hydridotris(3,5-dimethylpyrazolyl)borate)) and InBr3 at a 1:1 molar ratio afforded molybdenum-indane complexes (Et4N[TpMo(CO)3(InBr3)] 1 and Et4N[Tp*Mo(CO)3(InBr3)] 2). In addition, tungsten-indane complexes, Et4N[TpW(CO)3(InBr3)] 3 and Et4N[Tp*W(CO)3(InBr3)] 4, were obtained by the reaction of corresponding tungsten complexes. Complex 4 reacted with H2O to form the hydrido complex Tp*W(CO)3H, in which the W-In bond was cleaved. On the other hand, 4 reacted with three equiv. of AgNO3 to form Et4N[Tp*W(CO)3{In(ONO2)}] 5, in which three substituents on the In were exchanged while retaining the W-In dative bond. Complexes 1-5 were fully characterized using NMR measurements and elemental analyses, and the structures of 1-5 and Et4N[Tp*W(CO)3] were determined via X-ray crystallography. These are the first examples of mononuclear molybdenum- and tungsten-indane complexes with Mo-In and W-In dative bonds.

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