RESUMO
The presence of diffuse morphogen gradients in tissues supports a view in which growth is locally homogenous. Here we challenge this view: we used a high-resolution quantitative approach to reveal significant growth variability among neighboring cells in the shoot apical meristem, the plant stem cell niche. This variability was strongly decreased in a mutant impaired in the microtubule-severing protein katanin. Major shape defects in the mutant could be related to a local decrease in growth heterogeneity. We show that katanin is required for the cell's competence to respond to the mechanical forces generated by growth. This provides the basis for a model in which microtubule dynamics allow the cell to respond efficiently to mechanical forces. This in turn can amplify local growth-rate gradients, yielding more heterogeneous growth and supporting morphogenesis.
Assuntos
Adenosina Trifosfatases/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/citologia , Arabidopsis/metabolismo , Meristema/citologia , Adenosina Trifosfatases/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Homeostase , Katanina , Meristema/crescimento & desenvolvimento , Meristema/metabolismo , Microtúbulos/metabolismo , Modelos Biológicos , Morfogênese , Mutação , Células Vegetais/fisiologia , Brotos de Planta/citologia , Brotos de Planta/crescimento & desenvolvimento , Estresse MecânicoRESUMO
Ligandrol, also known as LGD-4033, belongs to the group of selective androgen receptor modulators (SARMs). Ligandrol was first included in the WADA Prohibited List in 2018. This work presents a method that allows for the detection and identification of ligandrol and its metabolite in athletes' urine and in dietary supplements by means of ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Samples were prepared according to an approach involving acid hydrolysis and double liquid-liquid extraction (LLE). Furthermore, due to the lack of reference material for ligandrol metabolites, the urine collected from the control excretion study was analyzed. The presented method is appropriate to monitor ligandrol and its metabolites. The samples collected for doping control purpose contained multiple metabolites, which may potentially rule out the hypothesis of ingesting a single 1 µg or 10 µg dose only. Another aspect to take into account is that ligandrol can be applied together with SARMs, steroids, and GHSs. This will also affect the substances' metabolism and elimination. It is also worth noting that dietary supplements may contain ligandrol as an official ingredient or as a contaminant. The described method may be usefully applied by other anti-doping or toxicological laboratories.
Assuntos
Dopagem Esportivo , Humanos , Dopagem Esportivo/prevenção & controle , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Xenobióticos , Detecção do Abuso de Substâncias/métodos , Androgênios/metabolismo , Antagonistas de AndrogêniosRESUMO
Plant ferritin is suggested as a good source of iron for human. Usually present in trace amounts, it was induced in legumes seeds by their sprouting in FeSO4 solution. Fortified sprouts were digested in the in vitro model of the human gastrointestinal tract. ~49% of lupine and ~ 45% of soy proteins were extracted into gastric fluid and next ~ 12% and only ~ 1% into intestine fluid from lupine and soybean, respectively. Gastric digestion released mainly ferrous iron (~ 85% from lupine and ~ 95% in soybean sprouts). Complexed iron constituted ~ 43% of total iron in intestine after lupine digestion and ~ 55% after soybean digestion. Intestine digestion doubled the total iron released from lupine sprouts (from ~ 21% up to 38%), while in soybean it increased from ~ 16% up to ~ 23%. Ferritin presence was confirmed by the specific antibodies in digestive fluids, but it is only partially extracted from sprouts during in vitro digestion.
Assuntos
Ferro , Lupinus , Humanos , Ferro/metabolismo , Glycine max , Ferritinas , Verduras , DigestãoRESUMO
Plants are multicellular organisms of a unique structure because their tissues consist of two interwoven networks: a network of interconnected protoplasts that is embedded in a network of tightly joined cell walls [...].
Assuntos
Plantas , Protoplastos , Fenômenos Biomecânicos , Biofísica , Parede CelularRESUMO
This review is devoted to the structure, assembly and function of cuticle. The topics are discussed from the mechanical perspective and whenever the data are available a special attention is paid to the cuticle of perianth organs, i.e., sepals, petals or tepals. The cuticle covering these organs is special in both its structure and function and some of these peculiarities are related to the cuticle mechanics. In particular, strengthening of the perianth surface is often provided by a folded cuticle that functionally resembles profiled plates, while on the surface of the petal epidermis of some plants, the cuticle is the only integral continuous layer. The perianth cuticle is distinguished also by those aspects of its mechanics and development that need further studies. In particular, more investigations are needed to explain the formation and maintenance of cuticle folding, which is typical for the perianth epidermis, and also to elucidate the mechanical properties and behavior of the perianth cuticle in situ. Gaps in our knowledge are partly due to technical problems caused by very small thicknesses of the perianth cuticle but modern tools may help to overcome these obstacles.
Assuntos
Epiderme Vegetal/ultraestrutura , Fenômenos Mecânicos , Lipídeos de Membrana/química , Lipídeos de Membrana/metabolismo , Epiderme Vegetal/metabolismoRESUMO
Honeybee venom is a source of proteins with allergenic properties which can result in in various symptoms, ranging from local reactions through to systematic life-threatening anaphylaxis, or even death. According to the World Allergy Organization (WAO), honeybee venom allergy is one of the most common causes of anaphylaxis. Among the proteins present in honeybee venom, 12 protein fractions were registered by the World Health Organization's Allergen Nomenclature Sub-Committee (WHO/IUIS) as allergenic. Most of them are highly immunogenic glycoproteins that cross-react with IgE and, as a consequence, may give false positive results in allergy diagnosis. Allergenic fractions are different in terms of molecular weight and biological activity. Eight of these allergenic fractions have also been identified in honey. This explains frequent adverse reactions after consuming honey in people allergic to venom and sheds new light on the causes of allergic symptoms in some individuals after honey consumption. At the same time, it also indicates the possibility of using honey as a natural source of allergen in specific immunotherapy.
Assuntos
Alérgenos/efeitos adversos , Venenos de Abelha/efeitos adversos , Hipersensibilidade/etiologia , Alérgenos/imunologia , Animais , Venenos de Abelha/imunologia , Abelhas/imunologia , Glicoproteínas/efeitos adversos , Glicoproteínas/imunologia , Humanos , Hipersensibilidade/imunologia , Imunoglobulina E/imunologia , Proteínas de Insetos/efeitos adversos , Proteínas de Insetos/imunologiaRESUMO
About 50-70% of patients allergic to birch pollen suffer from sensitization after apple ingestion. Apple allergenicity was established in only few varieties. Studies were performed on apple fruits of 21 traditional and nine modern varieties organically, intensively, or integratively produced. The aim of the study was to assess whether the factors like cultivation method, maturity stage, genotype, or type of tissue place an impact on the allergenic potential of apples. To answer these questions, we used semiquantitative real-time PCR, ELISA, and immunoblotting. Apple allergen genes present divergent expression across apple cultivars. Expression of the Mal d 1.06A correlates with the Mal d 1 level and is affected by the cultivation method and maturity of the fruit. The content of the main allergen Mal d 1 varied widely across cultivars. Interestingly, in our study, the Gala variety presented a low Mal d 1 concentration regardless of the cultivation method. Based on the Mal d 1.06A expression, the Mal d 1 protein content, and the immunoreactivity assay, the Kandil Sinap, Kosztela, Rumianka from Alma-Ata, Kantówka Gdanska, Reinette Coulon, and Gala cultivars emerged as potentially hypoallergenic apple cultivars. Our study allowed distinguishing between potentially low, medium, and highly allergenic varieties.
Assuntos
Antígenos de Plantas/imunologia , Hipersensibilidade Alimentar/imunologia , Malus/genética , Malus/imunologia , Proteínas de Plantas/imunologia , Antígenos de Plantas/genética , Ensaio de Imunoadsorção Enzimática , Frutas/genética , Frutas/imunologia , Regulação da Expressão Gênica de Plantas , Humanos , Soros Imunes , Immunoblotting , Proteínas de Plantas/genética , Reação em Cadeia da Polimerase , Análise de Componente PrincipalRESUMO
The relatively thick primary walls of epidermal and collenchyma cells often form waviness on the surface that faces the protoplast when they are released from the tensile in-plane stress that operates in situ. This waviness is a manifestation of buckling that results from the heterogeneity of the elastic strain across the wall. In this study, this heterogeneity was confirmed by the spontaneous bending of isolated wall fragments that were initially flat. We combined the empirical data on the formation of waviness in growing cell walls with computations of the buckled wall shapes. We chose cylindrical-shaped organs with a high degree of longitudinal tissue stress because in such organs the surface deformation that accompanies the removal of the stress is strongly anisotropic and leads to the formation of waviness in which wrinkles on the inner wall surface are always transverse to the organ axis. The computations showed that the strain heterogeneity results from individual or overlaid gradients of pre-stress and stiffness across the wall. The computed wall shapes depend on the assumed wall thickness and mechanical gradients. Thus, a quantitative analysis of the wall waviness that forms after stress removal can be used to assess the mechanical heterogeneity of the cell wall.
Assuntos
Parede Celular/metabolismo , Helianthus/fisiologia , Hordeum/fisiologia , Taraxacum/fisiologia , Fenômenos Biomecânicos , Cotilédone/fisiologia , Módulo de Elasticidade , Hipocótilo/fisiologiaRESUMO
PREMISE OF THE STUDY: In numerous vascular plants, pavement cells of the leaf epidermis are shaped like a jigsaw-puzzle piece. Knowledge about the subcellular pattern of growth that accompanies morphogenesis of such a complex shape is crucial for studies of the role of the cytoskeleton, cell wall and phytohormones in plant cell development. Because the detailed growth pattern of the anticlinal and periclinal cell walls remains unknown, our aim was to measure pavement cell growth at a subcellular resolution. METHODS: Using fluorescent microbeads applied to the surface of the adaxial leaf epidermis of Arabidopsis thaliana as landmarks for growth computation, we directly assessed the growth rates for the outer periclinal and anticlinal cell walls at a subcellular scale. KEY RESULTS: We observed complementary tendencies in the growth pattern of the outer periclinal and anticlinal cell walls. Central portions of periclinal walls were characterized by relatively slow growth, while growth of the other wall portions was heterogeneous. Local growth of the periclinal walls accompanying lobe development after initiation was relatively fast and anisotropic, with maximal extension usually in the direction along the lobe axis. This growth pattern of the periclinal walls was complemented by the extension of the anticlinal walls, which was faster on the lobe sides than at the tips. CONCLUSIONS: Growth of the anticlinal and outer periclinal walls of leaf pavement cells is heterogeneous. The growth of the lobes resembles cell elongation via diffuse growth rather than tip growth.
Assuntos
Arabidopsis/citologia , Epiderme Vegetal/citologia , Folhas de Planta/citologia , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/ultraestrutura , Parede Celular/ultraestrutura , Microscopia de Fluorescência , Microesferas , Epiderme Vegetal/crescimento & desenvolvimento , Epiderme Vegetal/ultraestrutura , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/ultraestruturaRESUMO
Background and Aims: The capitulum of Helichrysum bracteatum is surrounded by scarious involucral bracts that perform hygroscopic movements leading to bract bending toward or away from the capitulum, depending on cell wall water status. The present investigation aimed at explaining the mechanism of these movements. Methods: Surface strain and bract shape changes accompanying the movements were quantified using the replica method. Dissection experiments were used to assess the contribution of different tissues in bract deformation. Cell wall structure and composition were examined with the aid of light and electron microscopy as well as confocal Raman spectroscopy. Key Results: At the bract hinge (organ actuator) longitudinal strains at opposite surfaces differ profoundly. This results in changes of hinge curvature that drive passive displacement of distal bract portions. The distal portions in turn undergo nearly uniform strain on both surfaces and also minute shape changes. The hinge is built of sclerenchyma-like abaxial tissue, parenchyma and adaxial epidermis with thickened outer walls. Cell wall composition is rather uniform but tissue fraction occupied by cell walls, cell wall thickness, compactness and cellulose microfibril orientation change gradually from abaxial to adaxial hinge surface. Dissection experiments show that the presence of part of the hinge tissues is enough for movements. Conclusions: Differential strain at the hinge is due to adaxial-abaxial gradient in structural traits of hinge tissues and cell walls. Thus, the bract hinge of H. bracteatum is a structure comprising gradually changing tissues, from highly resisting to highly active, rather than a bi-layered structure with distinct active and resistance parts, often ascribed for hygroscopically moving organs.
Assuntos
Parede Celular/fisiologia , Helichrysum/fisiologia , Folhas de Planta/fisiologia , Água/fisiologiaRESUMO
N,N-dimethyl-2-phenylpropan-1-amine (NN-DMPPA) is a new designer stimulant prohibited in sport in-competition according to the List of Prohibited Substances and Methods published by the World Anti-Doping Agency (WADA). The first published data on the excretion study of NN-DMPPA to support the knowledge of NN-DMPPA in routine anti-doping control have been presented. The reliable gas chromatography-mass spectrometry quantitative method (GC-MS) has been validated and applied to the excretion study of NN-DMPPA. The validation parameters of the GC-MS method for determination of NN-DMPPA in human urine were the linear calibration range of 100 to 7500 ng/mL, the LOD of 13.9 ng/mL and the LOQ of 42.2 ng/mL. According to the obtained repeatability, intermediate precision, and trueness, the applied GC-MS method was precise and accurate. Urine samples from three volunteers in the excretion study were collected for 5 days after single oral administration of the supplement NOXPUMP containing NN-DMPPA. The obtained results showed the maximum concentration of NN-DMPPA (189-303 ng/mL) in urine samples at a time of 2-3 h post-administration. The NN-DMPPA concentration in urine samples was higher than 50 ng/mL until 22-23 h after the dietary supplement ingestion. This means that according to the WADA rules the use of a supplement containing NN-DMPPA may be related to a positive case when athletes took this supplement in-competition. Moreover, excretion results demonstrate also that NN-DMPPA may be detected in urine samples by the applied GC-MS method till 46 h after supplement administration. Additionally, the excretion study of ß-methylphenethylamine as the second prohibited substance present in the supplement NOXPUMP has been investigated. Graphical Abstract Excretion study of new designer stimulant, N,N-dimethyl-2-phenylpropan-1-amine, and ß-methylphenethylamine following single oral NOXPUMP supplement dose.
Assuntos
Suplementos Nutricionais/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Substâncias para Melhoria do Desempenho/urina , Propilaminas/urina , Detecção do Abuso de Substâncias/métodos , Administração Oral , Adulto , Dopagem Esportivo/prevenção & controle , Feminino , Humanos , Masculino , Taxa de Depuração Metabólica , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Urinálise/métodosRESUMO
Ferritin-iron is currently considered as one of the most promising iron forms to prevent iron deficiency anaemia. We found that the cultivation of soybean seeds in a solution of ferrous sulfate results in material with extremely high iron content - 560.6 mg Fe/100 g of dry matter, while ferritin iron content was 420.5 mg/100 g dry matter. To assess the potential adverse effects of a preparation containing such a high concentration of iron, male and female Wistar rats were exposed via diet to 10, 30, 60 g soybean sprouts powder/kg feed for 90 days. There were no differences in final body weight and mean food consumption between controls and rats administered sprouts. No statistically significant differences in haematology and clinical chemistry parameters were found between controls and treated rats. Microscopic examination of 22 tissues did not reveal any pathology due to soybean sprouts intake. Long term administration of the test material did not cause oxidative damage to DNA and protein in the liver as evidenced by the unchanged basal levels of DNA damage as well as carbonyl groups content. Lipid peroxidation was slightly increased only in females. The activity of several antioxidant enzymes: superoxide dismutase, glutathione peroxidase and glutathione S-transferase was increased, which substantially enhanced the antioxidant status in the liver from the rats treated with soybean sprouts. Hence, the material tested can be recommended as a component of food supplements for individuals with iron deficiency anaemia and inflammatory bowel diseases.
Assuntos
Anemia Ferropriva/tratamento farmacológico , Ferritinas/efeitos adversos , Alimento Funcional/efeitos adversos , Glycine max/química , Ferro/efeitos adversos , Anemia Ferropriva/sangue , Animais , Antioxidantes/metabolismo , Dano ao DNA/efeitos dos fármacos , Suplementos Nutricionais , Modelos Animais de Doenças , Feminino , Compostos Ferrosos/metabolismo , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Pós/efeitos adversos , Ratos , Ratos Wistar , Plântula/química , Plântula/metabolismo , Sementes/química , Sementes/metabolismo , Glycine max/metabolismoRESUMO
According to the World Anti-Doping Agency (WADA) Prohibited List, glucocorticosteroids are prohibited in competition and only when administered by oral, intravenous, intramuscular or rectal routes. Up to now, in order to differentiate whether glucocorticosteroids were administered by one of the prohibited routes or not, a specific reporting limit for urinary concentrations of parent compounds and their metabolites was established at 30 ng/mL. Additionally, the new specific regulation starting from 1 September 2014 for budesonide have been introduced that the 6ß-hydroxybudesonide shall be targeted. Budesonide is a glucocorticosteroid used mainly by inhalation for asthma management. Interestingly, anti-doping laboratory statistics show that budesonide adverse analytical findings (AAF) constitute almost 50% of all reported glucocorticosteroid AAFs, even though budesonide possesses a very low systemic activity which may cause performance enhance effects. This work presents the results of five studies of controlled budesonide administration carried out on professional athletes. The samples were analyzed by using a quantitative HPLC/MS/MS method for 16α-hydroxy-prednisolone, the most abundant budesonide metabolite in urine. Our data clearly show that inhalation of budesonide at least 12 h before a competition at therapeutic doses leads to appearance of the main budesonide metabolite in concentrations exceeding prior reporting limit for this compound. Therefore, our work strongly supports recent WADA decision not to target the main budesonide metabolite using the same reporting limit as for other glucocorticosteroids.
Assuntos
Budesonida/metabolismo , Dopagem Esportivo , Cromatografia Líquida de Alta Pressão , Humanos , Espectrometria de Massas em TandemRESUMO
Number of shift workers increases in developed as well as in developing countries every year and equals 15- 20% of total amount of working people in Europe, 20% of total count of workers in United States of America, 6-32% in Asian countries and 8.1% workers in Poland. This type of employment is connected with such sectors of economy as medical care, industry, mining, transportation, communication and hospitality. The literature review analyses health effects of shift work and night work in the area of gastroenterology, circulatory system, oncologic diseases, neuropsychiatric and sleep disorders. In summary shift and night work have negative impact on human health. Further investigations analyzing impact of shift and night work are needed.
Assuntos
Ritmo Circadiano , Jornada de Trabalho em Turnos/efeitos adversos , Doenças Cardiovasculares/etiologia , Gastroenteropatias/etiologia , Humanos , Neoplasias/etiologia , Transtornos do Sono-Vigília/etiologiaRESUMO
BACKGROUND AND AIMS: The arrangement of flowers in inflorescence shoots of Arabidopsis thaliana represents a regular spiral Fibonacci phyllotaxis. However, in the cuc2 cuc3 double mutant, flower pedicels are fused to the inflorescence stem, and phyllotaxis is aberrant in the mature shoot regions. This study examined the causes of this altered development, and in particular whether the mutant phenotype is a consequence of defects at the shoot apex, or whether post-meristematic events are involved. METHODS: The distribution of flower pedicels and vascular traces was examined in cross-sections of mature shoots; sequential replicas were used to investigate the phyllotaxis and geometry of shoot apices, and growth of the young stem surface. The expression pattern of CUC3 was analysed by examining its promoter activity. KEY RESULTS: Phyllotaxis irregularity in the cuc2 cuc3 double mutant arises during the post-meristematic phase of shoot development. In particular, growth and cell divisions in nodes of the elongating stem are not restricted in the mutant, resulting in pedicel-stem fusion. On the other hand, phyllotaxis in the mutant shoot apex is nearly as regular as that of the wild type. Vascular phyllotaxis, generated almost simultaneously with the phyllotaxis at the apex, is also much more regular than pedicel phyllotaxis. The most apparent phenotype of the mutant apices is a higher number of contact parastichies. This phenotype is associated with increased meristem size, decreased angular width of primordia and a shorter plastochron. In addition, the appearance of a sharp and deep crease, a characteristic shape of the adaxial primordium boundary, is slightly delayed and reduced in the mutant shoot apices. CONCLUSIONS: The cuc2 cuc3 double mutant displays irregular phyllotaxis in the mature shoot but not in the shoot apex, thus showing a post-meristematic effect of the mutations on phyllotaxis. The main cause of this effect is the formation of pedicel-stem fusions, leading to an alteration of the axial positioning of flowers. Phyllotaxis based on the position of vascular flower traces suggests an additional mechanism of post-meristematic phyllotaxis alteration. Higher density of flower primordia may be involved in the post-meristematic effect on phyllotaxis, whereas delayed crease formation may be involved in the fusion phenotype. Promoter activity of CUC3 is consistent with its post-meristematic role in phyllotaxis.
Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Fatores de Transcrição/genética , Arabidopsis/anatomia & histologia , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/metabolismo , Flores/anatomia & histologia , Flores/genética , Flores/crescimento & desenvolvimento , Inflorescência/anatomia & histologia , Inflorescência/genética , Inflorescência/crescimento & desenvolvimento , Meristema/citologia , Meristema/genética , Meristema/crescimento & desenvolvimento , Mutação , Fenótipo , Brotos de Planta/anatomia & histologia , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Regiões Promotoras Genéticas/genética , Fatores de Transcrição/metabolismoRESUMO
BACKGROUND: The impact of myocardial viral persistence on the clinical outcome of patients with dilated cardiomyopathy (DCM) is still open to question. METHODS: Fifty-two patients with DCM were enrolled and followed for a median of 3.8 years with respect to death or heart transplantation. Studied patients were clinically stable for at least 6 months before hospitalization. They underwent coronary angiography and endomyocardial biopsy. Specimens were examined by histo- and immunohistochemistry, and the viral genomes of parvovirus B19, cytomegalovirus (CMV), Coxsackie B virus (CVB), and hepatitis B and C viruses were studied by real-time polymerase chain reaction. RESULTS: Forty-two out of 52 patients were available for clinical follow-up. The viral genome was detected in the myocardium of 32 out of 42 patients. Among the viruses studied, CMV and CVB were the most frequently found. Nine out of 42 patients achieved the predefined study end point. No statistically significant correlation was found between the presence of a persistent viral genome and study end point. No statistically significant relationship between viral genomes studied and immunohistology results was detected. CONCLUSIONS: High prevalence of a viral genome in the myocardium of patients with DCM did not have an influence on their long-term clinical outcome.
Assuntos
Cardiomiopatia Dilatada/virologia , Genoma Viral/genética , Coração/virologia , Parvovirus B19 Humano/genética , Viroses/virologia , Adulto , Idoso , Biópsia , Cardiomiopatia Dilatada/diagnóstico , Citomegalovirus/genética , Citomegalovirus/isolamento & purificação , DNA Viral/genética , Enterovirus Humano B/genética , Enterovirus Humano B/isolamento & purificação , Feminino , Seguimentos , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Vírus da Hepatite B/genética , Vírus da Hepatite B/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Parvovirus B19 Humano/isolamento & purificaçãoRESUMO
RATIONALE: Therapeutic approaches concerning attention-deficit hyperactivity disorder (ADHD) commonly include the administration of drugs amplifying cerebral dopamine and norepinephrine signals. Among these, compounds belonging to the Prohibited List as established by the World Anti-Doping Agency (WADA) are present such as amfetamine or methylphenidate, and abuse of these can result in sanctions for athletes. The recently approved therapeutic lisdexamfetamine represents a slow-release prodrug of amfetamine for ADHD treatment. In order to support doping control laboratories in differentiating the abuse of amfetamine from a therapeutic administration of lisdexamfetamine, the determination of the prodrug from urine is desirable. Since approximately 2% of lisdexamfetamine are eliminated intact into urine, a liquid chromatography/high-resolution/high accuracy mass spectrometric method was developed, allowing the target analyte and one of its metabolites (4-hydroxyamfetamine sulfate) to be accurately quantified. METHODS: Urine samples were fortified with fourfold deuterated lisdexamfetamine and analyzed directly using ultrahigh-performance liquid chromatography (UHPLC) interfaced via electrospray ionization to a second-generation quadrupole-orbitrap mass spectrometer. The assay was characterized concerning specificity, limits of quantification (0.15-5 ng/mL), intraday and interday imprecision (4-22%), accuracy (90-120%), linearity, and ion suppression/enhancement effects. A patient's urine samples were analyzed to provide proof-of-principle data demonstrating that the intact prodrug lisdexamfetamine is detectable in urine up to 11 h post-administration at concentrations up to 80 ng/mL. Moreover, amfetamine and sulfoconjugated 4-hydroxyamfetamine were measured, yielding up to 1146 and 56 ng/mL, respectively. CONCLUSIONS: Considering the observed comparably low urinary concentrations of lisdexamfetamine and 4-hydroxyamfetamine sulfate, the preferred minimally labor-intense sample preparation, and the necessity of fast and robust result generation, the employed instrumental setup proved fit-for-purpose in sports drug testing.
Assuntos
Dextroanfetamina/urina , Dopagem Esportivo , Espectrometria de Massas/métodos , Dextroanfetamina/química , Feminino , Humanos , Limite de Detecção , Modelos Lineares , Dimesilato de Lisdexanfetamina , Masculino , Pró-Fármacos , Reprodutibilidade dos TestesRESUMO
Novel substances of expected doping activity are constantly introduced to the market. ß-Methylphenethylamine (BMPEA) is classified as a doping agent by the World Anti-Doping Agency as it is a positional isomer of amphetamine. In this work, the development and application of a simple and rapid analytical procedure that enables discrimination between both isomers is described. The analytes of interest were extracted from urine by a two-step liquid-liquid extraction and then analyzed by UPLC/MS/MS under isocratic conditions. The entire analytical procedure was validated by evaluating its selectivity, discrimination capabilities, carry-over, sensitivity, and influence of matrix effects on its performance. Application of the method resulted in detection of BMPEA in eight anti-doping samples, including the first report of adverse analytical finding regarding its use. Further analysis showed that BMPEA may be eliminated unchanged along with its phase II conjugates, the hydrolysis of which may considerably improve detection capabilities of the method. Omission of the hydrolysis step may therefore, produce false-negative results. Testing laboratories should also carefully examine their LC/MS/MS-based amphetamine and BMPEA findings as both isomers fragment yielding comparable collision-induced dissociation spectra and their insufficient chromatographic separation may result in misidentification. This is of great importance in case of forensic analyses as BMPEA is not controlled by the public law, and its manufacturing, distribution, and use are legal.
Assuntos
Anfetaminas/urina , Cromatografia Líquida , Dopagem Esportivo , Metanfetamina/análogos & derivados , Detecção do Abuso de Substâncias/métodos , Espectrometria de Massas em Tandem , Estimulantes do Sistema Nervoso Central/análise , Reações Falso-Negativas , Toxicologia Forense , Humanos , Hidrólise , Limite de Detecção , Espectrometria de Massas , Metanfetamina/urina , Sensibilidade e Especificidade , TemperaturaRESUMO
An isolate of lead-ferritin obtained from soybean seeds sprouted in 25 mM of PbNO3 was introduced into the diet of both iron-deficient and iron non-deficient male rats. After a 21-day administration period, statistical differences in the lead accumulation in the femurs of the rats were noted. Iron-deficient rats accumulated more than four times the amount of lead in their bones than rats without iron-deficiency. No further decrease was observed in haemoglobin concentrations in the groups of animals fed with lead isolates, either iron-deficient or iron non-deficient. Also, no differences in the mean corpuscular haemoglobin (MCH) and mean corpuscular volume (MCV) were observed at the end of the experiment in the group of iron non-deficient rats fed with lead-ferritin isolate compared to the control group of iron non-deficient rats. In the iron-deficient group fed with lead-ferritin isolate, a small increase in haemoglobin concentrations, MCH, MCV and mean corpuscular haemoglobin concentrations (MCHC) was recorded. The results presented in this paper confirm that lead from the tested preparation-lead ferritin isolate-was better absorbed by those rats with induced iron deficiency anaemia. Additionally, we may also suspect based on the obtained results that absorption of ferritin-iron depends on iron status in the body.
Assuntos
Anemia Ferropriva/dietoterapia , Ferritinas/farmacocinética , Glycine max/química , Proteínas de Plantas/farmacocinética , Anemia Ferropriva/tratamento farmacológico , Animais , Índices de Eritrócitos/efeitos dos fármacos , Ferritinas/isolamento & purificação , Hemoglobinas/análise , Absorção Intestinal , Ferro/metabolismo , Deficiências de Ferro , Chumbo/análise , Chumbo/farmacocinética , Masculino , Proteínas de Plantas/isolamento & purificação , Ratos Wistar , Sementes/químicaRESUMO
Ethanol exposure during pregnancy is an important problem and is the cause of fetal alcohol syndrome (FAS) and fetal alcohol spectrum disorder (FASD). The etiology of FAS and FASD can be elucidated using animal models. Recently, a novel model, the zebrafish (Danio rerio), has garnered the interest of researchers. This study confirmed the negative influence of ethyl alcohol (0.5 %, 1.5 %, and 2.5 % v/v) on the development of zebrafish embryos. The observed malformations included pericardial and yolk sac edema, increased body curvature, tail edema, and a decreased embryo hatching rate. The differences in body length, body width, and heart rate were statistically significant. Due to the similarities in the quantity and function of ethanol biotransformation enzymes between zebrafish and mammals, this study investigated the nonoxidative metabolites of ethanol - ethyl glucuronide (EtG) and ethyl sulfate (EtS) - in zebrafish following ethanol exposure. This research confirmed that EtG and EtS concentrations can be measured in zebrafish embryos, and the levels of these metabolites appear to be associated with the ethyl alcohol concentration in the medium.