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1.
Int J Mol Sci ; 24(11)2023 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-37298668

RESUMO

A pollen grain is a unique haploid organism characterized by a special composition and structure. The pollen of angiosperms and gymnosperms germinate in fundamentally similar ways, but the latter also have important features, including slow growth rates and lower dependence on female tissues. These features are, to some extent, due to the properties of pollen lipids, which perform a number of functions during germination. Here, we compared the absolute content and the fatty acid (FA) composition of pollen lipids of two species of flowering plants and spruce using GC-MS. The FA composition of spruce pollen differed significantly, including the predominance of saturated and monoene FAs, and a high proportion of very-long-chain FAs (VLCFAs). Significant differences between FAs from integumentary lipids (pollen coat (PC)) and lipids of gametophyte cells were found for lily and tobacco, including a very low unsaturation index of the PC. The proportion of VLCFAs in the integument was several times higher than in gametophyte cells. We found that the absolute content of lipids in lily pollen is almost three times higher than in tobacco and spruce pollen. For the first time, changes in the FA composition were analyzed during pollen germination in gymnosperms and angiosperms. The stimulating effect of H2O2 on spruce germination also led to noticeable changes in the FA content and composition of growing pollen. For tobacco in control and test samples, the FA composition was stable.


Assuntos
Ácidos Graxos , Magnoliopsida , Cycadopsida , Peróxido de Hidrogênio , Pólen , Nicotiana , Lipídeos
2.
Allergy ; 77(6): 1751-1760, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34837242

RESUMO

BACKGROUND: Recent studies showed that a single injection of human monoclonal allergen-specific IgG antibodies significantly reduced allergic symptoms in birch pollen-allergic patients. Since the production of full monoclonal antibodies in sufficient amounts is laborious and expensive, we sought to investigate if smaller recombinant allergen-specific antibody fragments, that is, nanobodies, have similar protective potential. For this purpose, nanobodies specific for Bet v 1, the major birch pollen allergen, were generated to evaluate their efficacy to inhibit IgE-mediated responses. METHODS: A cDNA-VHH library was constructed from a camel immunized with Bet v 1 and screened for Bet v 1 binders encoding sequences by phage display. Selected nanobodies were expressed, purified, and analyzed in regards of epitope-specificity and affinity to Bet v 1. Furthermore, cross-reactivity to Bet v 1-homologues from alder, hazel and apple, and their usefulness to inhibit IgE binding and allergen-induced basophil activation were investigated. RESULTS: We isolated three nanobodies that recognize Bet v 1 with high affinity and cross-react with Aln g 1 (alder) and Cor a 1 (hazel). Their epitopes were mapped to the alpha-helix at the C-terminus of Bet v 1. All nanobodies inhibited allergic patients' polyclonal IgE binding to Bet v 1, Aln g 1, and Cor a 1 and partially suppressed Bet v 1-induced basophil activation. CONCLUSION: We identified high-affinity Bet v 1-specific nanobodies that recognize an important IgE epitope and reduce allergen-induced basophil activation revealing the first proof that allergen-specific nanobodies are useful tools for future treatment of pollen allergy.


Assuntos
Hipersensibilidade , Anticorpos de Domínio Único , Alérgenos , Antígenos de Plantas , Epitopos , Humanos , Imunoglobulina E , Proteínas de Plantas , Pólen
3.
N Engl J Med ; 366(5): 409-20, 2012 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-22296075

RESUMO

BACKGROUND: The efficacy and safety of oral ulipristal acetate for the treatment of symptomatic uterine fibroids before surgery are uncertain. METHODS: We randomly assigned women with symptomatic fibroids, excessive uterine bleeding (a score of >100 on the pictorial blood-loss assessment chart [PBAC, an objective assessment of blood loss, in which monthly scores range from 0 to >500, with higher numbers indicating more bleeding]) and anemia (hemoglobin level of ≤10.2 g per deciliter) to receive treatment for up to 13 weeks with oral ulipristal acetate at a dose of 5 mg per day (96 women) or 10 mg per day (98 women) or to receive placebo (48 women). All patients received iron supplementation. The coprimary efficacy end points were control of uterine bleeding (PBAC score of <75) and reduction of fibroid volume at week 13, after which patients could undergo surgery. RESULTS: At 13 weeks, uterine bleeding was controlled in 91% of the women receiving 5 mg of ulipristal acetate, 92% of those receiving 10 mg of ulipristal acetate, and 19% of those receiving placebo (P<0.001 for the comparison of each dose of ulipristal acetate with placebo). The rates of amenorrhea were 73%, 82%, and 6%, respectively, with amenorrhea occurring within 10 days in the majority of patients receiving ulipristal acetate. The median changes in total fibroid volume were -21%, -12%, and +3% (P=0.002 for the comparison of 5 mg of ulipristal acetate with placebo, and P=0.006 for the comparison of 10 mg of ulipristal acetate with placebo). Ulipristal acetate induced benign histologic endometrial changes that had resolved by 6 months after the end of therapy. Serious adverse events occurred in one patient during treatment with 10 mg of ulipristal acetate (uterine hemorrhage) and in one patient during receipt of placebo (fibroid protruding through the cervix). Headache and breast tenderness were the most common adverse events associated with ulipristal acetate but did not occur significantly more frequently than with placebo. CONCLUSIONS: Treatment with ulipristal acetate for 13 weeks effectively controlled excessive bleeding due to uterine fibroids and reduced the size of the fibroids. (Funded by PregLem; ClinicalTrials.gov number, NCT00755755.).


Assuntos
Leiomioma/tratamento farmacológico , Menorragia/tratamento farmacológico , Norpregnadienos/uso terapêutico , Receptores de Progesterona/antagonistas & inibidores , Neoplasias Uterinas/tratamento farmacológico , Administração Oral , Adulto , Anemia/etiologia , Método Duplo-Cego , Feminino , Humanos , Análise de Intenção de Tratamento , Leiomioma/complicações , Leiomioma/cirurgia , Menorragia/etiologia , Pessoa de Meia-Idade , Norpregnadienos/administração & dosagem , Norpregnadienos/efeitos adversos , Neoplasias Uterinas/complicações , Neoplasias Uterinas/cirurgia , Útero/patologia , Adulto Jovem
4.
Gastroenterology ; 141(2): 476-85, 485.e1-11, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21684283

RESUMO

BACKGROUND & AIMS: Gastric cancer (GC) is a heterogeneous disease comprising multiple subtypes that have distinct biological properties and effects in patients. We sought to identify new, intrinsic subtypes of GC by gene expression analysis of a large panel of GC cell lines. We tested if these subtypes might be associated with differences in patient survival times and responses to various standard-of-care cytotoxic drugs. METHODS: We analyzed gene expression profiles for 37 GC cell lines to identify intrinsic GC subtypes. These subtypes were validated in primary tumors from 521 patients in 4 independent cohorts, where the subtypes were determined by either expression profiling or subtype-specific immunohistochemical markers (LGALS4, CDH17). In vitro sensitivity to 3 chemotherapy drugs (5-fluorouracil, cisplatin, oxaliplatin) was also assessed. RESULTS: Unsupervised cell line analysis identified 2 major intrinsic genomic subtypes (G-INT and G-DIF) that had distinct patterns of gene expression. The intrinsic subtypes, but not subtypes based on Lauren's histopathologic classification, were prognostic of survival, based on univariate and multivariate analysis in multiple patient cohorts. The G-INT cell lines were significantly more sensitive to 5-fluorouracil and oxaliplatin, but more resistant to cisplatin, than the G-DIF cell lines. In patients, intrinsic subtypes were associated with survival time following adjuvant, 5-fluorouracil-based therapy. CONCLUSIONS: Intrinsic subtypes of GC, based on distinct patterns of expression, are associated with patient survival and response to chemotherapy. Classification of GC based on intrinsic subtypes might be used to determine prognosis and customize therapy.


Assuntos
Biomarcadores Tumorais/metabolismo , Caderinas/metabolismo , Galectina 4/metabolismo , Perfilação da Expressão Gênica , Neoplasias Gástricas/classificação , Neoplasias Gástricas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Cisplatino/uso terapêutico , Feminino , Fluoruracila/uso terapêutico , Humanos , Estimativa de Kaplan-Meier , Masculino , Análise em Microsséries , Pessoa de Meia-Idade , Compostos Organoplatínicos/uso terapêutico , Oxaliplatina , Prognóstico , Modelos de Riscos Proporcionais , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/patologia , Taxa de Sobrevida , Adulto Jovem
5.
Food Chem Toxicol ; 44(4): 517-21, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16242229

RESUMO

Ginsan is a polysaccharide extracted from the roots of Panax ginseng, and it has earlier been reported to have an immunostimulatory effect. In the present study, the frequency of micronucleated polychromatic erythrocytes (MNPCE) was assessed in the bone marrow of C57BL/6 male mice treated with ginsan [100, 200 or 300 mg/kg body weight (b.w.)] or amifostine (200mg/kg b.w.) 30 min before as well as 15 min after 1.5 Gy of gamma-irradiation. Ginsan and amifostine did not alter the frequency of MNPCE of control mice (P>0.05), showing that they are non-mutagenic per se; gamma-irradiation induced a statistically significant (P<0.001) increase of MNPCE and decrease of PCE/NCE ratio (P<0.001) compared to control group. However, ginsan applied 30 min before or 15 min after irradiation reduced MNPCE in a dose-dependent manner. Amifostine (200mg/kg b.w.) did not reduce radiation-induced MNPCE, but stimulated erythropoiesis, when administered before irradiation. Based on the above results, radioprotective effect of ginsan can be partially attributed to reduction of radiation-induced genotoxicity.


Assuntos
Antimutagênicos/farmacologia , Eritrócitos/efeitos dos fármacos , Panax , Fitoterapia , Polissacarídeos/farmacologia , Amifostina/farmacologia , Animais , Relação Dose-Resposta a Droga , Eritrócitos/efeitos da radiação , Raios gama , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Micronúcleos com Defeito Cromossômico/efeitos dos fármacos , Micronúcleos com Defeito Cromossômico/efeitos da radiação , Extratos Vegetais/farmacologia , Raízes de Plantas
6.
J Neurobiol ; 54(4): 638-47, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12555275

RESUMO

Estrogen plays an important role during differentiation of midbrain dopaminergic neurons. This is indicated by the presence of estrogen receptors and the transient expression of the estrogen-forming enzyme aromatase within the dopaminergic cell groups. We have previously shown that estrogen regulates the plasticity of dopamine cells through the stimulation of neurite growth/arborization. In this study, we have analyzed the capability of estrogen to influence the activity of developing mouse dopamine neurons. The expression of tyrosine hydroxylase (TH) was assessed by competitive RT-PCR and Western blotting. The developmental expression of TH in the ventral midbrain was studied from embryonic day 15 until postnatal day 15 and revealed highest TH levels early postnatally. This profile coincides with the transient aromatase expression in this brain area. Using cultured midbrain cells, we found that estrogen increased TH mRNA/protein levels. The application of the estrogen receptor antagonist ICI 182,780 resulted in a complete inhibition of estrogen effects. To verify these data in vivo, fetuses were exposed in utero from E15 until birth to the aromatase inhibitor CGS 16949A or to CGS supplemented with estrogen. CGS caused a robust reduction in TH mRNA/protein levels in the midbrain, which could be restored by estrogen substitution. Taken together, our data strongly suggest that estrogen controls dopamine synthesis in the developing nigrostriatal dopaminergic system and support the concept that estrogen is implicated in the regulation of ontogenetic steps but also in the function of midbrain dopamine neurons.


Assuntos
Estradiol/análogos & derivados , Estrogênios/farmacologia , Expressão Gênica/efeitos dos fármacos , Mesencéfalo/efeitos dos fármacos , Tirosina 3-Mono-Oxigenase/metabolismo , Animais , Animais Recém-Nascidos , Western Blotting , Células Cultivadas , Interações Medicamentosas , Estradiol/farmacologia , Antagonistas de Estrogênios/farmacologia , Estrogênios/agonistas , Fadrozol/farmacologia , Feminino , Fulvestranto , Hipoxantina Fosforribosiltransferase/genética , Hipoxantina Fosforribosiltransferase/metabolismo , Masculino , Mesencéfalo/embriologia , Mesencéfalo/enzimologia , Camundongos , Camundongos Endogâmicos BALB C , RNA Mensageiro/biossíntese , Receptores de Estrogênio/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Fatores Sexuais , Tirosina 3-Mono-Oxigenase/genética
7.
Endocrinology ; 143(8): 3175-8, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12130584

RESUMO

Estrogens stimulate the differentiation of neurons and neural networks in the CNS. The concordance of the cellular responses of estrogens and growth factors suggests that both factors may interact on the cellular level to ensure their developmental role. We have put forward this hypothesis and analyzed the effect of estrogens on the expression of glial cell line-derived neutrotrophic factor (GDNF) in developing hypothalamic cells. Using Western blotting and competitive RTPCR, we have demonstrated that 17beta-estradiol (E2) increases the expression of GDNF in hypothalamic cell cultures. E2-induced GDNF expression was seen in neurons but not astrocytes. GDNF induction by E2 appeared to be transmitted through nonclassical estrogen action, since the application of the nuclear estrogen receptor antagonists ICI 182, 780 did not abolish this effect. Only inhibitors of intracellular Ca(2+) and cAMP/protein kinase A signaling were effective in preventing E2 effects. We conclude that E2 is capable of influencing GDNF expression in the developing hypothalamus. Thus, it is conceivable that developmental E2 effects in the hypothalamus are partially mediated through the regulation of other important developmental signals such as growth factors.


Assuntos
Estradiol/farmacologia , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Hipotálamo/embriologia , Hipotálamo/metabolismo , Fatores de Crescimento Neural , Proteínas do Tecido Nervoso/genética , Animais , Células Cultivadas , Estradiol/análogos & derivados , Feminino , Fulvestranto , Fator Neurotrófico Derivado de Linhagem de Célula Glial , Camundongos , Camundongos Endogâmicos BALB C , Proteínas do Tecido Nervoso/biossíntese , Gravidez
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