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1.
Ecotoxicol Environ Saf ; 274: 116193, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38460407

RESUMO

Chlorocholine chloride (CCC) is a plant growth regulator used worldwide that is detectable in cereals, fruits and animal products. The health effects of CCC exposure have raised public concern. Our previous research showed that CCC exposure decreased testosterone synthesis in pubertal rats. However, little is known about whether and how pubertal CCC exposure impacts spermatogenesis. In this study, we used BALB/c mice and spermatogonia-derived GC-1 cells to examine CCC-induced spermatogenic dysfunction. In vivo, pubertal CCC exposure led to decreased testicular weight, decreased testicular germ cells and poor sperm quality. This effect worsened after cessation of CCC exposure for the next 30 days. RNA-seq and western blot analysis revealed that CCC induced aryl hydrocarbon receptor (AhR) signaling, endoplasmic reticulum stress (ERS) and ferritinophagy. Increased iron content and lipid peroxidation levels were also observed in CCC-treated testes. In vitro, it was identified that iron overload mediated by enhanced ferritinophagy occurred in CCC-treated GC-1 cells, which might be attributed to the PERK pathway in ERS. Further, for the first time, our study elucidated the involvement of AhR in CCC-induced iron overload, which aggravated testicular oxidative damage via lipid peroxidation. Considering the adverse impact of CCC exposure on rodents, supportive evidence from GC-1 cells, and the critical importance of spermatogenesis on male development, the effects of CCC on the male reproduction warrant increased attention.


Assuntos
Acetatos , Clormequat , Sobrecarga de Ferro , Fenóis , Espermatogênese , Animais , Masculino , Camundongos , Ratos , Clormequat/metabolismo , Clormequat/toxicidade , Sobrecarga de Ferro/metabolismo , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Sementes , Espermatogênese/efeitos dos fármacos , Testículo , eIF-2 Quinase/efeitos dos fármacos , eIF-2 Quinase/metabolismo
2.
Food Chem Toxicol ; 185: 114475, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38286265

RESUMO

Chlormequat chloride (CCC), as a widely used plant growth regulator, can cause impaired sperm quality and decreased testosterone synthesis in pubertal rats, but the underlying mechanism remains unclear. The purpose of this study was to elucidate the toxicokinetics and tissue distribution of CCC, as well as the possible mechanism of CCC-induced impairment in sperm quality. The concentration of CCC reached its peak 1 h after a single dose (200 mg/kg·bw) administration in mice plasma, and a bimodal phenomenon appeared in the testes, liver, and epididymis. In vivo, 200 mg/kg CCC caused testicular damage and impaired sperm quality in pubertal mice, and the expression of p-tyrosine and GSK3α decreased in cauda epididymidis, sperm and testes. CCC also caused the down-regulation of AKAP4 and the up-regulation of calmodulin (CaM), and activated the PI3K/AKT signaling pathway in the testes. In vitro, CCC reduced the levels of p-tyrosine, AKAP4 and GSK3α, increased the level of CaM and activated the PI3K/AKT signaling pathway in GC-1 cells. CaM antagonist (W-7 hydrochloride) and PI3K inhibitor (LY294002) can effectively improve the expression of GSK3α and AKAP4 by suppressing the PI3K/AKT signaling pathway in GC-1 cells treated with CCC. It was indicated that CCC induced impairment in sperm quality might be partially related to the activation of PI3K/AKT signaling pathway mediated by CaM.


Assuntos
Acetatos , Clormequat , Fenóis , Proteínas Proto-Oncogênicas c-akt , Camundongos , Ratos , Masculino , Animais , Clormequat/metabolismo , Clormequat/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Calmodulina/metabolismo , Calmodulina/farmacologia , Sêmen/metabolismo , Transdução de Sinais , Espermatozoides , Tirosina/metabolismo
3.
Se Pu ; 40(9): 843-853, 2022 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-36156631

RESUMO

Chromatography combined with mass spectrometry is the most commonly used detection technology, and it offers the advantages of high sensitivity and high selectivity. The quick, easy, inexpensive, effective, rugged, and safe (QuEChERS) method is low-cost, effective, and time efficient. The application of the QuEChERS has now been extended to the analysis of contaminants in food samples. The aim of the study was to identify different concentration levels of multiple harmful drug residues in bean sprouts. In this study, QuEChERS coupled with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was established for the simultaneous determination of 40 plant growth regulators, fungicides, insecticides, and antibiotics in bean sprouts. In the HPLC-MS/MS experiment, gibberellic acid, 4-fluorophenoxyacetic acid, chloramphenicol, N6-(δ2-isopentenyl)-adenine, 6-benzylaminopurine, 4-chlorophenoxyacetic acid, and 2,4-dichlorophenoxyacetic acid (2,4-D) were analyzed by MS/MS with negative electrospray ionization (ESI-). The other 33 target analytes (chlormequat, ronidazole, metronidazole, pymetrozine, dimetridazole, methomyl, carbendazim, enoxacin, levofloxacin, pefloxacin mesylate, norfloxacin, ciprofloxacin, enrofloxacin, thiabendazole, lomefloxacin, chlorpyrifos, sarafloxacin, imidacloprid, etc.) were analyzed by MS/MS with positive electrospray ionization (ESI+). Sensitive MS conditions were realized by optimizing the instrumental parameters such as the desolvent temperature, collision energy, spraying needle position, precursor ions, and product ions. Then, the optimal pretreatment method was determined by comparing the recovery rates of the 40 drugs obtained with different extraction solvents (methanol, acetonitrile, acetonitrile containing 0.1% ammonia, acetonitrile with 1% acetic acid), different extraction methods (ultrasonic extraction, shaking extraction), and purification with primary secondary amine (PSA) and C18. In this study, the bean sprouts samples were extracted twice by 10 mL acetonitrile with 1% acetic acid, and extracted under ultrasonic conditions. Then, the extracting solution was only cleaned with 100 mg C18. The chromatographic separation of the 40 compounds was accomplished on a Waters ACQUITY UPLC BEH C18 column (100 mm×2.1 mm, 1.7 µm) with gradient elution. Methanol and 0.01% formic acid aqueous solution were used as the mobile phases. The 40 compounds were analyzed in the multiple reaction monitoring (MRM) mode. The matrix matching external standard method was used for quantitative determination. The results showed that the 40 compounds could be analyzed within 15 min. Under the optimized conditions, the calibration curves showed good linearities for the 40 compounds, and the coefficients of determination (r2) were greater than 0.99 in the range of 2-200 µg/L. The limits of detection (LODs) and limits of quantification (LOQs) were in the range of 0.1-3 µg/kg and 0.3-9 µg/kg, respectively. Using negative bean sprouts as the substrates, the recovery tests were carried out at three spiked levels of 5, 10, and 50 µg/kg. The average recoveries of the 40 drugs were 78.5% to 115.3%, and the corresponding relative standard deviations (RSDs) were 1.3% to 9.7% (n=6). This method was successfully applied to the analysis of the 40 drug residues in 21 batches of local bean sprouts in Handan city. The results revealed the presence of extensive drug residues in the bean sprouts. The 26 batches were detected to varying degrees, among which 4-chlorophenoxyacetic acid, carbendazim, 6-benzyladenine, 2,4-D, enrofloxacin, and metronidazole were detected at high rates. The detection rates of 4-chlorophenoxyacetic acid, 6-benzyladenine, carbendazim, 2,4-D, gibberellic acid, and enrofloxacin were 28.6%, 19.0%, 9.5%, 9.5%, 4.8%, and 4.8%, respectively. The contents ranged from 37.5-352.4, 32.4-273.1, 28.8-38.7, 316.1-20.2, 19.9 and 13.6 µg/kg, respectively. Given its advantages of simplicity, rapidness, and high sensitivity, the developed method can be used for the rapid and accurate determination of trace levels of the 40 drug residues in large quantities of bean sprouts.


Assuntos
Clorpirifos , Fungicidas Industriais , Inseticidas , Ácido 2,4-Diclorofenoxiacético/análogos & derivados , Ácido 2,4-Diclorofenoxiacético/análise , Acetonitrilas , Adenina , Amônia , Antibacterianos , Benzimidazóis , Compostos de Benzil , Carbamatos , Cloranfenicol/análise , Clormequat , Cromatografia Líquida de Alta Pressão , Ciprofloxacina , Dimetridazol , Enoxacino , Enrofloxacina , Fungicidas Industriais/análise , Giberelinas , Inseticidas/análise , Levofloxacino , Metanol , Metomil , Metronidazol , Norfloxacino , Pefloxacina , Reguladores de Crescimento de Plantas/análise , Purinas , Ronidazole , Solventes , Espectrometria de Massas em Tandem , Tiabendazol
4.
J Environ Sci Health B ; 56(3): 212-221, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33560902

RESUMO

Tebuconazole (TBZ) and Chlormequat chloride (CCC) combination has been established as highly effective in reducing plant height of lodging prone wheat varieties. In this work, a novel analytical method employing the quick, easy, cheap, effective, rugged and safe (QuEChERS) cleanup technique and LC-MS/MS (liquid chromatography-tandem mass spectroscopy) was developed for simultaneous estimation of TBZ and CCC in wheat grains and harvest stage plant leaves. A total of 10 mL of acetonitrile and 50 mg of primary secondary amine (PSA) sorbent was consumed in the optimized QuEChERS process for leaves and grain samples. The LC-MS/MS analysis was performed using a C-18 column operating under electrospray ionization in positive mode. The QuEChERS approach achieved extraction recoveries in the acceptable range of 70%-120%, for both the compounds and was validated in terms of accuracy, precision, sensitivity and linearity. Persistence study was conducted using Lihocin (CCC 50% SL), Folicur (TBZ 25.9% EC) and their combination tank mix (Lihocin + Folicur-50% SL + 25.9% EC) applied as foliar spray twice in wheat crop (tester tall variety C-306). The results demonstrated that the developed QuEChERS-LCMS/MS is rapid and confirmatory for simultaneous quantification of both the test analytes in wheat crop.


Assuntos
Fracionamento Químico/métodos , Clormequat/análise , Espectrometria de Massas em Tandem/métodos , Triazóis/análise , Triticum/química , Acetonitrilas , Agricultura/métodos , Cromatografia Líquida/métodos , Produtos Agrícolas/química , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Folhas de Planta/química , Reprodutibilidade dos Testes , Sementes/química , Sensibilidade e Especificidade
5.
Toxicol Lett ; 319: 1-10, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31689472

RESUMO

Chlorocholine chloride (CCC), a plant growth retardant, may act as an endocrine disruptor. Our previous study showed that pubertal CCC exposure in rats might decrease testosterone (T) synthesis. This study observed the changes in pubertal development and reproduction of male rats exposed to CCC and its underlying mechanisms. Rats were exposed to CCC (0, 75, 137.5 and 200 mg/kg bw/day) from postnatal day 23 to 60. The results showed that CCC treatment delayed the onset of puberty and reduced the relative organ weight of prostate. Seminiferous tubules with deciduous spermatogenic cells were observed in the 200 mg/kg bw/day group. Sexual behavior was inhibited in the 137.5 and 200 mg/kg bw/day groups. Sperm motility, litter size and normalized anogenital distance (AGD) of male pups were decreased in the 137.5 and 200 mg/kg bw/day groups. Serum kisspeptin level and serum and testicular levels of T were reduced in all CCC treated groups. Crucial hormones in hypothalamic-pituitary-testicular (HPT) axis were reduced subsequently after CCC treatment. Collectively, our results demonstrated that CCC might disturb HPT axis through suppressing the secretion of kisspeptin and subsequently lead to delayed puberty onset and impaired reproductive functions.


Assuntos
Clormequat/toxicidade , Reprodução/efeitos dos fármacos , Maturidade Sexual/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Genitália/anatomia & histologia , Genitália/efeitos dos fármacos , Genitália/crescimento & desenvolvimento , Hormônios Esteroides Gonadais/sangue , Kisspeptinas/metabolismo , Tamanho da Ninhada de Vivíparos/efeitos dos fármacos , Masculino , Tamanho do Órgão/efeitos dos fármacos , Próstata/efeitos dos fármacos , Próstata/crescimento & desenvolvimento , Ratos , Ratos Sprague-Dawley , Túbulos Seminíferos/efeitos dos fármacos , Comportamento Sexual Animal/efeitos dos fármacos , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos , Testosterona/sangue
6.
J Chromatogr A ; 1592: 101-111, 2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-30638711

RESUMO

In this study, a modified Quick Polar Pesticides (QuPPe) method, optimized by a central composite design, was developed to determine quaternary ammonium pesticides (QUATs) residues in barley and wheat by ultra-high-performance liquid chromatographic tandem mass spectrometry (UHPLC-MS/MS) using a hydrophilic interaction chromatography (HILIC) column. Considering the high polarity of these compounds, special conditions of sample preparation and analysis are required. Different mobile phases, extraction procedure and clean-up were evaluated. An isocratic elution with aqueous solution of ammonium formate 60 mmol L-1 (pH 3.7) and acetonitrile, 40:60 (v/v), was selected. Water and acidified methanol as extraction solvent, without heating, and a clean-up with dichloromethane, chitosan and acetonitrile presented good results. The validated method presented satisfactory selectivity, linearity, matrix effect, trueness and precision, providing recoveries from 93 to 110% with RSD < 13% for barley, and 70 to 115% with RSD < 18% for wheat. The complexity of these matrices requires the calibration in matrix and the diluted standard addition calibration (DSAC) procedure has been shown to be an excellent option to compensate for the matrix effect and the losses of the analytes in the extraction. Real samples of barley and wheat were analyzed and 60% presented concentrations of paraquat above the maximum limits allowed by the European Union. The modified QuPPe method combined with DSAC and HILIC-UHPLC-MS/MS demonstrated to be an effective approach to determine QUATs in barley and wheat, and is a good alternative for routine analysis. The use of the biosorbent chitosan is effective, low cost and more ecological when compared to others conventional sorbents.


Assuntos
Cromatografia Líquida , Análise de Alimentos/instrumentação , Análise de Alimentos/métodos , Hordeum/química , Praguicidas/análise , Espectrometria de Massas em Tandem , Triticum/química , Calibragem , Clormequat/análise , Diquat/análise , Paraquat/análise , Piperidinas/análise , Compostos de Amônio Quaternário/análise
7.
J Environ Sci Health B ; 54(2): 98-111, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30600768

RESUMO

In this study, a two-dimensional liquid chromatography tandem mass spectrometry method was developed and validated for the determination of pesticide residues and contaminants in whole wheat grains and oats. The samples were extracted with a mixture of acetonitrile and water and were injected into the two-dimensional LC-MS/MS system without any further clean-up or sample preparation. Samples were analyzed with four different matrix matched calibrations. Matrix effects were evaluated by comparing analyte signals in the respective matrix matched standard with the neat solvent standards. The final method was validated according to the current Eurachem validation guide and SANTE document. The number of successfully validated analytes throughout all three validation levels in oats and wheat, respectively, were as follows: 330 and 316 out of 370 pesticides, 6 and 13 out of 18 pyrrolizidine alkaloids and 7 out of 9 regulated mycotoxins. Moreover, both plant growth regulators mepiquat and chlormequat as well as the tropane alkaloids atropine and scopolamine met the validation criteria. The majority of pesticides showed limits of detection below 1 µg kg-1, pyrrolizidine alkaloids below 0.7 µg kg-1, tropane alkaloids below 0.2 µg kg-1, growth regulators below 0.7 µg kg-1 and mycotoxins below 8 µg kg-1 in both matrices.


Assuntos
Avena/química , Cromatografia Líquida/métodos , Contaminação de Alimentos/análise , Espectrometria de Massas em Tandem/métodos , Triticum/química , Clormequat/análise , Análise de Alimentos/métodos , Limite de Detecção , Micotoxinas/análise , Sistemas On-Line , Resíduos de Praguicidas/análise , Piperidinas/análise , Reguladores de Crescimento de Plantas/análise , Alcaloides de Pirrolizidina/análise , Reprodutibilidade dos Testes , Tropanos/análise
8.
Prep Biochem Biotechnol ; 48(9): 867-876, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30296385

RESUMO

Betulin (B) and betulinic acid (BA) are two triterpenes with diverse pharmacological and physiological actions. Elicitation of Betula pendula Roth cell cultures by elicitors is an excellent strategy to increase B and BA levels. Six abiotic and biotic elicitors were studied to improve accumulation of B and BA in the cell culture of B. pendula. The B and BA production in treated cells was verified by HPLC. The results showed the maximum growth index (7) on day 3 in cells treated with 0.5 mg L-1 chlorocholine chloride (CCC). The increased accumulation of BA in the cells treated with 200 mg L-1 of chitosan was found to be 5.9 × (6.5 mg g-1 DW) higher over control cells. Treating the cells with 2 mg L-1 of CCC, after 7 days, led to 149.3× enhancement of B content (19.4 mg g-1 DW) over the controls. Production of this triterpenoid at a much shorter time with a much higher growth rate can be economic and lead to producing large amounts of B and BA for anti-cancer and HIV drugs preparation.


Assuntos
Betula/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Triterpenos/metabolismo , Acetatos/farmacologia , Fármacos Anti-HIV/metabolismo , Antineoplásicos Fitogênicos/biossíntese , Betula/efeitos dos fármacos , Técnicas de Cultura de Células/métodos , Sobrevivência Celular/efeitos dos fármacos , Clormequat/farmacologia , Ciclopentanos/farmacologia , Oxilipinas/farmacologia , Triterpenos Pentacíclicos , Ácido Salicílico/farmacologia , Ácido Betulínico
9.
J Genet ; 97(2): 439-451, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29932064

RESUMO

The fruitfulness of grapevines (Vitis viniferaL.) is determined to a large extent by the differentiation of uncommitted meristems, especially in the second-crop production of some varieties, where the intermediate of inflorescence and tendril accounts for a significant proportion in two-crop-a-year grape culture system. The differentiation of uncommitted lateral meristem was reported to be regulated by a network, whose backbone was composed of several floral meristem identity genes. In the present study, the phylogenetics of grape floral meristem identity genes with their orthologues in other species, and their conserved domain and interaction networks were analysed. In addition, the effects of chlormequat chloride and pinching treatments on the expression profiles of floral meristem identity genes and content of gibberellic acid (GAs) and zeatin riboside (ZR), as well as the ratio of ZR/GAs in buds that were used to produce the second crop, and the ratio of inflorescence induction of the second crop were studied in 'Summer Black'. The present results showed that floral meristem identity genes of grape and their orthologues in one or more among Malus domastic, Citrus sinensis, heobroma cacaoT, Nicotiana tabacum, Solanum lycopersicum and Glycine hirsutum, probably originated from a common ancestor. Interaction networks of six grape-floral meristem identity genes indicated that the inflorescence induction and floral development were regulated by one more complex network, and expression profiles of genes that involved in this network could be affected by each other. Expression profiles of eight floral meristem identity genes were affected by chlormequat chloride and pinching treatments, and higher expression levels of FT, TFL1A and TFL1B, as well as lower expression levels of LFY from 3 days before full bloom to 11 days after full bloom were thought to play important roles in promoting the formation of inflorescence primordial of the second crop, and higher expression levels of CAL A, SOC1 and TFL1A at 18 days after full bloom (DAF) could promote the development of inflorescence primordial. In addition, lower ratio of ZR/GAs at 3 days before full bloom and 4 days after full bloom could promote the formation of uncommitted lateral meristems in chlormequat chloride and pinching-treated plants, and higher ratio at 11 days after full bloom was the main reason for the formation of more inflorescences after chlormequat chloride treatment.


Assuntos
Perfilação da Expressão Gênica/métodos , Genes de Plantas/genética , Inflorescência/genética , Meristema/genética , Vitis/genética , Clormequat/farmacologia , Evolução Molecular , Flores/genética , Flores/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Redes Reguladoras de Genes/genética , Inflorescência/crescimento & desenvolvimento , Meristema/crescimento & desenvolvimento , Filogenia , Reguladores de Crescimento de Plantas/farmacologia , Proteínas de Plantas/classificação , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Mapas de Interação de Proteínas/genética , Vitis/efeitos dos fármacos , Vitis/crescimento & desenvolvimento
10.
J Pharm Biomed Anal ; 153: 175-181, 2018 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-29499460

RESUMO

Adenosine deaminase (ADA), which is a key enzyme in the metabolism of purine nucleosides, plays important roles in diverse disorders, such as tuberculosis, diabetes, liver disorders, and cancer. Determination of the activities of ADA and its isoenzymes in body fluids has received considerable attention in the diagnosis and treatment of relative diseases. Ultraviolet spectroscopy with adenosine (AD) as a substrate is a classical approach for screening potential ADA inhibitors by measuring the decrease in substrate (AD) at 265 nm or increase in the product (inosine) at 248 nm. However, AD and inosine share a very close maximum absorption wavelength, and the reaction is uncertain and is frequently interfered by the background color of matrix compounds or plant extracts. Thus, the method usually yields false positive or negative results. In this study, a novel, rapid, sensitive, and accurate ultra-high-performance liquid chromatography-Q exactive hybrid quadrupole orbitrap high-resolution accurate mass spectrometric (UHPLC-Q-Orbitrap HRMS) method was developed for determining and screening ADA inhibitors by directly determining the deamination product of AD, inosine. A proper separation was achieved for inosine and chlormequat (internal standard) within 2 min via isocratic elution (0.1% formic acid:methanol = 85:15, v/v) at a flow rate of 0.3 mL min-1 on a Waters ACQUITY HSS T3 column (2.1 mm × 100 mm, 1.8 µm) following a simple precipitation of proteins. The intra- and inter-day precisions of the developed method were below 7.17% and 8.99%, respectively. The method exhibited advantages of small total reaction volume (60 µL), short running time (2 min), high sensitivity (lowest limit of quantification of 0.02 µM for inosine), and low cost (small enzyme consumption of 0.007 unit mL-1 for ADA and substrate of 3.74 µM for AD in individual inhibition), and no matrix effects (101.64%-107.12%). Stability results showed that all analytes were stable under the investigated conditions. The developed method was successfully applied to the detection of the inhibitory activity of ADA from traditional Chinese medicines.


Assuntos
Inibidores de Adenosina Desaminase/química , Adenosina Desaminase/química , Extratos Vegetais/química , Líquidos Corporais/química , Clormequat/química , Cromatografia Líquida de Alta Pressão/métodos , Inosina/química , Limite de Detecção , Medicina Tradicional Chinesa/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Massas em Tandem/métodos
11.
Toxicology ; 381: 1-9, 2017 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-28214531

RESUMO

Chlormequat Chloride (CCC), a widely used plant growth regulator, could decrease body weight in animals; however, the mechanism has not been well studied. This study was designed to evaluate the skeletal development toxicity of CCC on pubertal male Sprague-Dawley (SD) rats and to investigate whether CCC impacts the development of chondrocyte, osteoblast and osteoclast through growth hormone (GH) and insulin like growth factor 1 (IGF-I). Rats from 23 to 70 on postnatal days were exposed to CCC daily by gavage at doses of 0, 75, 150, and 300mg/kg bw/d. The results showed that the size of femurs and tibias, bone mineral density and biomechanical parameters were significantly decreased in the 300mg/kg bw/d group compared with the control group. The concentration of osteocalcin (OCN) and C-terminal telopeptide of type I collagen (CTX-I) in blood in the 150mg/kg bw/d group was also changed. The mRNA expression ratio of the receptor activator of NF-κB ligand (RANKL) and osteoprotegerin (OPG) in 150 and 300mg/kg bw/d group was increased. Histological analysis of proximal and distal epiphyseal plates of the right femurs showed that both the proliferative zone and hypertrophic zone narrowed in CCC-treated groups. The concentration of IGF-I in blood was reduced with an increase in exposure doses of CCC. The mRNA expression of growth hormone receptor (GHR) in tibia was decreased in the CCC-treated group. The results indicated that CCC might indirectly impact the formation and activation of chondrocytes, osteoblasts and osteoclasts because of the decline of GHR and IGF-I, leading to skeletal development damage.


Assuntos
Clormequat/toxicidade , Condrócitos/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Osteoclastos/efeitos dos fármacos , Esqueleto/efeitos dos fármacos , Animais , Peso Corporal , Densidade Óssea/efeitos dos fármacos , Condrócitos/metabolismo , Colágeno Tipo I/sangue , Relação Dose-Resposta a Droga , Fêmur/efeitos dos fármacos , Fêmur/metabolismo , Hormônio do Crescimento/metabolismo , Lâmina de Crescimento/efeitos dos fármacos , Lâmina de Crescimento/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , NF-kappa B/genética , NF-kappa B/metabolismo , Osteoblastos/metabolismo , Osteocalcina/sangue , Osteoclastos/metabolismo , Osteoprotegerina/genética , Osteoprotegerina/metabolismo , Peptídeos/sangue , Ligante RANK/genética , Ligante RANK/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores da Somatotropina/genética , Receptores da Somatotropina/metabolismo , Esqueleto/crescimento & desenvolvimento , Tíbia/efeitos dos fármacos , Tíbia/metabolismo
12.
Biosci. j. (Online) ; 32(6): 1493-1501, nov./dec. 2016. tab, graf
Artigo em Inglês | LILACS | ID: biblio-965785

RESUMO

Chlormequat chloride (CCC) is used to inhibit extension growth in cereals and promote branching and flowering in potted ornamental plants produced in greenhouses; however, experimental data on the use of CCC in field sunflower are limited. Field experiments were conducted to study the effect of foliar applications of CCC at rates of 3,000 g ha-1 (single application) and 3,000 plus 3,000 g ha-1 (double application) on the morphology and productivity of sunflower plants. CCC provoked some foliar injury on sunflower plants within a week after application, but the effect was transient; the symptoms were reduced over time and the plants recovered completely. Single application of CCC did not provide significant height reduction of sunflower plants as opposed to double application, which reduced plant height at maturity by 12.7% (or by 43.4 cm). Both application schemes promoted flowering and induced the production of more achenes, but finally resulted in reduced achene yield per plant by 17.8% and 20.3%, respectively, compared with the non-treated control. The achene yield reduction resulted by the reduction in the 100-achene weight. The study provides new evidence that allow a better understanding of the mode of action of CCC in sunflower. Overall, the foliar applications of CCC at the rates tested in this study either did not provide any advantage in terms of height reduction of sunflower plants or the height reduction achieved was accompanied by significant reduction in achene yield. On the basis of all the above, CCC does not appear to be a suitable growth regulator for the control of plant height in sunflower.


Chlormequat chloride (CCC) é usado para inibir o crescimento em altura em cereais e promover a ramificação e floração em plantas ornamentais envasadas produzidas em estufas; no entanto, os dados experimentais sobre o uso de CCC em girassol são limitados. Os experimentos de campo foram conduzidos para estudar o efeito de aplicações foliares de CCC a taxas de 3.000 g ha-1 (aplicação simples) e 3.000 + 3.000 g ha-1 (aplicação dupla) sobre a morfologia e a produtividade das plantas de girassol. A aplicação de CCC provocou algum dano nas folhas de girassol em uma semana após a aplicação, mas o efeito foi transitório; os sintomas foram reduzidos ao longo do tempo e as plantas recuperaram completamente. Aplicação simples de CCC não propiciaram redução significativa da altura de plantas de girassol em oposição à dupla aplicação, que provocou redução da altura das plantas, na maturidade, de 12.7% (ou 43.4 cm). Ambos os esquemas de aplicação promoveram floração e induziram a produção de mais aquênios, mas finalmente resultaram em redução do rendimento de aquênios por planta de 17.8% e 20.3%, respectivamente, em comparação com o controle não tratado. A redução de rendimento de aquênios foi provocada pela redução do peso de 100 aquénios, porque o número de aquénios enchidos não foi afectado significativamente. O estudo fornece novas evidências de que permitem uma melhor compreensão do modo de ação do CCC em girassol. No geral, as aplicações foliares de CCC nas taxas testadas neste estudo, ou não fornecem qualquer vantagem em termos de redução da altura de plantas de girassol, ou a redução da altura alcançada foi acompanhada de redução significativa no rendimento de aquênios. Com base no que precede, CCC não parece ser um regulador de crescimento adequado para o controle da altura das plantas em girassol.


Assuntos
Reguladores de Crescimento de Plantas , Clormequat , Helianthus
13.
BMC Plant Biol ; 16: 85, 2016 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-27072931

RESUMO

BACKGROUND: The plant-specific TCP transcription factor family, which is involved in the regulation of cell growth and proliferation, performs diverse functions in multiple aspects of plant growth and development. However, no comprehensive analysis of the TCP family in watermelon (Citrullus lanatus) has been undertaken previously. RESULTS: A total of 27 watermelon TCP encoding genes distributed on nine chromosomes were identified. Phylogenetic analysis clustered the genes into 11 distinct subgroups. Furthermore, phylogenetic and structural analyses distinguished two homology classes within the ClTCP family, designated Class I and Class II. The Class II genes were differentiated into two subclasses, the CIN subclass and the CYC/TB1 subclass. The expression patterns of all members were determined by semi-quantitative PCR. The functions of two ClTCP genes, ClTCP14a and ClTCP15, in regulating plant height were confirmed by ectopic expression in Arabidopsis wild-type and ortholog mutants. CONCLUSIONS: This study represents the first genome-wide analysis of the watermelon TCP gene family, which provides valuable information for understanding the classification and functions of the TCP genes in watermelon.


Assuntos
Citrullus/genética , Perfilação da Expressão Gênica/métodos , Genoma de Planta/genética , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Clormequat/farmacologia , Mapeamento Cromossômico/métodos , Cromossomos de Plantas/genética , Citrullus/efeitos dos fármacos , Citrullus/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Giberelinas/farmacologia , Família Multigênica , Filogenia , Reguladores de Crescimento de Plantas/farmacologia , Proteínas de Plantas/classificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Plântula/efeitos dos fármacos , Plântula/genética , Plântula/crescimento & desenvolvimento , Fatores de Transcrição/classificação
14.
Biol Res ; 47: 19, 2014 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-25027783

RESUMO

BACKGROUND: Effect of chlorocholine chloride (CCC) on phenolic acids composition and polyphenols accumulation in various anatomical parts (stems, leaves and inflorescences) of common buckwheat (Fagopyrum esculentum Moench) in the early stages of vegetation period were surveyed. RESULTS: Treatment of buckwheat seeds with 2% of CCC has been increased content of total phenolics in the stems, leaves and inflorescences. On analyzing the different parts of buckwheat plants, 9 different phenolic acids - vanilic acid, ferulic acid, trans-ferulic acid, chlorogenic acid, salycilic acid, cinamic acid, p-coumaric acid, p-anisic acid, methoxycinamic acid and catechins were identified. The levels of identified phenolic acids varied not only significantly among the plant organs but also between early stages of vegetation period. Same changes as in contents of chlorogenic acid, ferulic acid, trans-ferulic acid were found for content of salycilic acid. The content of these phenolic acids has been significant increased under effect of 2% CCC treatment at the phase I (formation of buds) in the stems and at the phase II (beginning of flowering) in the leaves and then inflorescences respectively. The content of catechins as potential buckwheat antioxidants has been increased at the early stages of vegetation period after treatment with 2% CCC. CONCLUSIONS: The obtained results suggest that influence of CCC on the phenolics composition can be a result of various mechanisms of CCC uptake, transforming and/or its translocation in the buckwheat seedlings.


Assuntos
Clormequat/farmacologia , Fagopyrum/efeitos dos fármacos , Hidroxibenzoatos/metabolismo , Polifenóis/biossíntese , Antioxidantes/análise , Antioxidantes/metabolismo , Catequina/análise , Ácido Clorogênico/análise , Cromatografia Líquida de Alta Pressão , Ácidos Cumáricos/análise , Fagopyrum/crescimento & desenvolvimento , Fagopyrum/metabolismo , Éteres de Hidroxibenzoatos/análise , Hidroxibenzoatos/química , Inflorescência/efeitos dos fármacos , Inflorescência/metabolismo , Molibdênio , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Caules de Planta/efeitos dos fármacos , Caules de Planta/metabolismo , Propionatos , Sementes/efeitos dos fármacos , Sementes/metabolismo , Compostos de Tungstênio
15.
Biol. Res ; 47: 1-7, 2014. graf, tab
Artigo em Inglês | LILACS | ID: biblio-950715

RESUMO

BACKGROUND: Effect of chlorocholine chloride (CCC) on phenolic acids composition and polyphenols accumulation in various anatomical parts (stems, leaves and inflorescences) of common buckwheat (Fagopyrum esculentum Moench) in the early stages of vegetation period were surveyed. RESULTS: Treatment of buckwheat seeds with 2% of CCC has been increased content of total phenolics in the stems, leaves and inflorescences. On analyzing the different parts of buckwheat plants, 9 different phenolic acids - vanilic acid, ferulic acid, trans-ferulic acid, chlorogenic acid, salycilic acid, cinamic acid, p-coumaric acid, p-anisic acid, methoxycinamic acid and catechins were identified. The levels of identified phenolic acids varied not only significantly among the plant organs but also between early stages of vegetation period. Same changes as in contents of chlorogenic acid, ferulic acid, trans-ferulic acid were found for content of salycilic acid. The content of these phenolic acids has been significant increased under effect of 2% CCC treatment at the phase I (formation of buds) in the stems and at the phase II (beginning of flowering) in the leaves and then inflorescences respectively. The content of catechins as potential buckwheat antioxidants has been increased at the early stages of vegetation period after treatment with 2% CCC. CONCLUSIONS: The obtained results suggest that influence of CCC on the phenolics composition can be a result of various mechanisms of CCC uptake, transforming and/or its translocation in the buckwheat seedlings.


Assuntos
Clormequat/farmacologia , Fagopyrum/efeitos dos fármacos , Polifenóis/biossíntese , Hidroxibenzoatos/metabolismo , Propionatos , Sementes/efeitos dos fármacos , Sementes/metabolismo , Catequina/análise , Ácido Clorogênico/análise , Cromatografia Líquida de Alta Pressão , Compostos de Tungstênio , Caules de Planta/efeitos dos fármacos , Caules de Planta/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Fagopyrum/crescimento & desenvolvimento , Fagopyrum/metabolismo , Ácidos Cumáricos/análise , Inflorescência/efeitos dos fármacos , Inflorescência/metabolismo , Éteres de Hidroxibenzoatos/análise , Hidroxibenzoatos/química , Molibdênio , Antioxidantes/análise , Antioxidantes/metabolismo
16.
Food Chem Toxicol ; 59: 438-45, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23822974

RESUMO

¹H Nuclear Magnetic Resonance spectroscopy has been used to profile urinary metabolites in male Fischer F344 rats in order to assess the metabolic changes induced by oral exposure to two benzimidazole fungicides (carbendazim and thiabendazole) and two bipyridyllium herbicides (chlormequat and mepiquat). Exposure levels were selected to be lower than those expected to cause overt signs of toxicity. We then compared the sensitivity of the metabolomics approach to more traditional methods of toxicity assessment such as the measurement of growth and organ weights. Separate, acute exposure experiments were conducted for each pesticide to identify potential metabolic markers of exposure across four doses (and a control). Growth, organ weights and feeding/drinking rates were not significantly affected by any compounds at any dose levels tested. In contrast, metabolic responses were detected within 8 and 24h for chlormequat and mepiquat, and after 24h for carbendazim and thiabendazole. These results demonstrate the potential for the use of metabolomics in food toxicity testing.


Assuntos
Contaminação de Alimentos , Fungicidas Industriais/farmacocinética , Herbicidas/farmacocinética , Metabolômica/métodos , Resíduos de Praguicidas/farmacocinética , Toxicologia/métodos , Animais , Benzimidazóis/administração & dosagem , Benzimidazóis/análise , Benzimidazóis/farmacocinética , Benzimidazóis/toxicidade , Biomarcadores/urina , Carbamatos/administração & dosagem , Carbamatos/análise , Carbamatos/farmacocinética , Carbamatos/toxicidade , Clormequat/administração & dosagem , Clormequat/análise , Clormequat/farmacocinética , Clormequat/toxicidade , Relação Dose-Resposta a Droga , Fungicidas Industriais/administração & dosagem , Fungicidas Industriais/análise , Fungicidas Industriais/toxicidade , Herbicidas/administração & dosagem , Herbicidas/análise , Herbicidas/toxicidade , Espectroscopia de Ressonância Magnética , Masculino , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/toxicidade , Resíduos de Praguicidas/urina , Piperidinas/administração & dosagem , Piperidinas/análise , Piperidinas/farmacocinética , Piperidinas/toxicidade , Análise de Componente Principal , Distribuição Aleatória , Ratos , Ratos Endogâmicos F344 , Tiabendazol/administração & dosagem , Tiabendazol/análise , Tiabendazol/farmacocinética , Tiabendazol/toxicidade , Reino Unido
17.
J Anim Physiol Anim Nutr (Berl) ; 85(1-2): 1-8, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11686767

RESUMO

A study was conducted to test the effect of chlorocholine chloride (CCC) on growth performance and the onset of laying in hens. One hundred and fifteen 3-week-old chickens were divided into four treatment groups of 39, 33, 31 and 12 chickens. They were placed on four dietary treatments consisting of 0 p.p.m. CCC (control), 5 p.p.m. CCC from 14 weeks of age (5 p.p.m. A), 5 p.p.m. CCC from the beginning (5 p.p.m. B), and 50 p.p.m. CCC from the beginning (50 p.p.m. B). The basal diets were formulated according to the growing period and were iso-nitrogenous and iso-energetic. The crude protein content was 17.99% dry matter and 14.63% dry matter during the first 3-8 weeks and 9-20 weeks, respectively. The energy content was 12.7 and 12.75 MJ metabolisable energy (ME)/kg dry matter for the respective two growth phases. Feed intake, bodyweight changes and egg production were measured. Blood samples for oestrogen determination were collected weekly from the 15th week until the first egg was laid. Depressive effects of 50 p.p.m. CCC on bodyweight gain during weeks 3-8 and feed efficiency over the whole period were observed. There were no treatment differences (p > 0.05) on feed intake, bodyweight gain during weeks 9-20 and age at the point of lay. CCC inclusion at 50 p.p.m. significantly (p < 0.05) stimulated the oestrogen concentration at 17 and 18 weeks of age, and was 65% higher than the control at 18 weeks.


Assuntos
Peso Corporal/efeitos dos fármacos , Galinhas/crescimento & desenvolvimento , Clormequat/administração & dosagem , Estrogênios/sangue , Oviposição/efeitos dos fármacos , Fatores Etários , Animais , Galinhas/fisiologia , Clormequat/farmacologia , Relação Dose-Resposta a Droga , Ingestão de Energia/efeitos dos fármacos , Feminino , Oviposição/fisiologia
18.
Rapid Commun Mass Spectrom ; 15(15): 1341-5, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11466795

RESUMO

Gas-phase cluster formation between the quaternary ammonium pesticides paraquat, diquat, difenzoquat, chlormequat and mepiquat, and chloride and acetate anions present in a liquid chromatography (LC) mobile phase, has been studied using electrospray mass spectrometry. The clusters of paraquat, mepiquat and chlormequat were revealed over the entire m/z range of the mass spectrometer, and their formation is dependent on the concentrations of both the cationic and the anionic species. Mepiquat and chlormequat form clusters of the type [2M(q)(+) + A(-)](+), where M(q)(+) is the quaternary ammonium cation and A(-) is the anion. Paraquat forms a cluster species with ammonia and also an ion-pair complex with chloride anions. Diquat and difenzoquat did not form observable ion-pair complexes or clusters with any of the anions studied. Competitive binding of acetate and chloride anions reflects the higher charge density of chloride, which forms the dominant clusters with mepiquat and chlormequat. The formation of cluster species has implications for the quantification of quaternary ammonium pesticides and may have an influence on the linearity of calibrations.


Assuntos
Praguicidas/química , Compostos de Amônio Quaternário/química , Espectrometria de Massas por Ionização por Electrospray , Acetatos/química , Cátions , Cloretos/química , Clormequat/química , Cromatografia Líquida , Diquat/química , Estrutura Molecular , Paraquat/química , Piperidinas/química , Pirazóis/química
19.
J Chromatogr A ; 914(1-2): 111-21, 2001 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-11358204

RESUMO

A method for the direct determination of paraquat, diquat, chlormequat and difenzoquat in water samples, using an on-line solid-phase extraction-liquid chromatography-tandem mass spectrometry system was developed. No sample preparation was required and the detection limits were below the European Union maximum residue levels. The chromatographic separation was performed using an XTera MS C8 column. The concentration of the ion pair reagent, the pH and the gradient elution were optimized to give high recoveries and good chromatographic resolution between quats. The detection was carried out using an ion trap as mass analyzer. Parameters such as the magnitude and duration of the resonant excitation voltage and the magnitude of the trapping RF voltage for full scan tandem mass spectrometry (MS-MS) experiments were studied to establish the optimal experimental conditions. Moreover, the accurate optimization of these parameters allowed MS-MS experiments of low mass ions, below m/z 200, providing unambiguous peak identification. Finally, the reproducibility of the proposed method was shown by good run-to-run and day-to-day precision values and its applicability to the determination of quats in drinking water was evaluated using spiked samples.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Herbicidas/análise , Compostos de Amônio Quaternário/análise , Clormequat/análise , Diquat/análise , Paraquat/análise , Pirazóis/análise , Sensibilidade e Especificidade , Espectrometria de Massas por Ionização por Electrospray , Abastecimento de Água/análise
20.
J Anal Toxicol ; 14(4): 257-8, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2395350

RESUMO

A 59-year-old white male accidentally ingested a mouthful of a plant growth chemical, Cycocel, containing 11.8% of the active ingredient (2-chloroethyl)trimethylammonium chloride (chlormequat). He was seen by a family physician and then transferred to a hospital where he died as a result of ventricular fibrillation, which progressed to asystole. Postingestion symptoms were typical of cholinergic crisis and included salivation, diaphoresis, bradycardia, visual disturbances, and seizure. Autopsy findings showed marked pulmonary edema, coronary atherosclerosis, atheromata of aorta, and localized adenocarcinoma of the prostate. Toxicological analyses of biological samples showed the presence of chlormequat in the stomach contents and urine.


Assuntos
Acidentes de Trabalho , Clormequat/intoxicação , Morte Súbita/etiologia , Compostos de Amônio Quaternário/intoxicação , Clormequat/metabolismo , Morte Súbita/patologia , Humanos , Masculino , Pessoa de Meia-Idade
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