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1.
Sci Rep ; 14(1): 3043, 2024 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-38321096

RESUMO

Immune checkpoints regulate the immune system response. Recent studies suggest that flavonoids, known as phytoestrogens, may inhibit the PD-1/PD-L1 axis. We explored the potential of estrogens and 17 Selective Estrogen Receptor Modulators (SERMs) as inhibiting ligands for immune checkpoint proteins (CTLA-4, PD-L1, PD-1, and CD80). Our docking studies revealed strong binding energy values for quinestrol, quercetin, and bazedoxifene, indicating their potential to inhibit PD-1 and CTLA-4. Quercetin and bazedoxifene, known to modulate EGFR and IL-6R alongside estrogen receptors, can influence the immune checkpoint functionality. We discuss the impact of SERMs on PD-1 and CTLA-4, suggesting that these SERMs could have therapeutic effects through immune checkpoint inhibition. This study highlights the potential of SERMs as inhibitory ligands for immune checkpoint proteins, emphasizing the importance of considering PD-1 and CTLA-4 inhibition when evaluating SERMs as therapeutic agents. Our findings open new avenues for cancer immunotherapy by exploring the interaction between various SERMs and immune checkpoint pathways.


Assuntos
Proteínas de Checkpoint Imunológico , Neoplasias , Humanos , Antígeno CTLA-4 , Antígeno B7-H1 , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Receptor de Morte Celular Programada 1 , Moduladores de Receptor Estrogênico , Quercetina , Imunoterapia , Neoplasias/terapia
2.
Bioorg Chem ; 141: 106816, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37716274

RESUMO

Pentamethinium indolium salts are promising fluorescence probes and anticancer agents with high mitochondrial selectivity. We synthesized two indolium pentamethinium salts: a cyclic form with quinoxaline directly incorporated in the pentamethinium chain (cPMS) and an open form with quinoxaline substitution in the γ-position (oPMS). To better understand their properties, we studied their interaction with mitochondrial phospholipids (cardiolipin and phosphatidylcholine) by spectroscopic methods (UV-Vis, fluorescence, and NMR spectroscopy). Both compounds displayed significant affinity for cardiolipin and phosphatidylcholine, which was associated with a strong change in their UV-Vis spectra. Nevertheless, we surprisingly observed that fluorescence properties of cPMS changed in complex with both cardiolipin and phosphatidylcholine, whereas those of oPMS only changed in complex with cardiolipin. Both salts, especially cPMS, display high usability in mitochondrial imaging and are cytotoxic for cancer cells. The above clearly indicates that conjugates of pentamethinium and quinoxaline group, especially cPMS, represent promising structural motifs for designing mitochondrial-specific agents.


Assuntos
Antineoplásicos , Cardiolipinas , Quinoxalinas/farmacologia , Sais , Antineoplásicos/farmacologia , Antineoplásicos/química , Fosfatidilcolinas
3.
Biomed Pharmacother ; 166: 115324, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37598475

RESUMO

TET proteins (methylcytosine dioxygenases) play an important role in the regulation of gene expression. Dysregulation of their activity is associated with many serious pathogenic states such as oncological diseases. Regulation of their activity by specific inhibitors could represent a promising therapeutic strategy. Therefore, this review describes various types of TET protein inhibitors in terms of their inhibitory mechanism and possible applicability. The potential and possible limitations of this approach are thoroughly discussed in the context of TET protein functionality in living systems. Furthermore, possible therapeutic strategies based on the inhibition of TET proteins are presented and evaluated, especially in the field of oncological diseases.


Assuntos
Dioxigenases , Dioxigenases/antagonistas & inibidores
4.
Biomed Pharmacother ; 163: 114758, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37141738

RESUMO

Treatment of metastatic cancer is one of the biggest challenges in anticancer therapy. Curcumin is interesting nature polyphenolic compound with unique biological and medicinal effects, including repression of metastases. High impact studies imply that curcumin can modulate the immune system, independently target various metastatic signalling pathways, and repress migration and invasiveness of cancer cells. This review discusses the potential of curcumin as an antimetastatic agent and describes potential mechanisms of its antimetastatic activity. In addition, possible strategies (curcumin formulation, optimization of the method of administration and modification of its structure motif) to overcome its limitation such as low solubility and bioactivity are also presented. These strategies are discussed in the context of clinical trials and relevant biological studies.


Assuntos
Antineoplásicos , Curcumina , Neoplasias , Humanos , Curcumina/farmacologia , Curcumina/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Antineoplásicos/química , Neoplasias/tratamento farmacológico
5.
Biomed Pharmacother ; 155: 113736, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36156366

RESUMO

Dysregulation of iron homeostasis is one of the important processes in the development of many oncological diseases, such as pancreatic cancer. Targeting it with specific agents, such as an iron chelator, are promising therapeutic methods. In this study, we tested the cytotoxicity of novel azulene hydrazide-hydrazone-based chelators against pancreatic cancer cell lines (MIA PaCa-2, PANC-1, AsPC-1). All prepared chelators (compounds 4-6) showed strong cytotoxicity against pancreatic cancer cell lines and high selectivity for cancer cell lines compared to the healthy line. Their cytotoxicity is lower than thiosemicarbazone-based chelators Dp44mT and DpC, but significantly higher than hydroxamic acid-based chelator DFO. The chelator tested showed mitochondrial and lysosomal co-localization and its mechanism of action was based on the induction of hypoxia-inducible factor-1-alpha (HIF-1α), N-myc downstream-regulated gene-1 (NDRG1) and transferrin receptor 1 (TfR1). This strongly implies that the cytotoxic effect of tested chelators could be associated with mitophagy induction. Lipinski's rule of five analyses was performed to determine whether the prepared compounds had properties ensuring their bioavailability. In addition, the drug-likeness and drug-score were calculated and discussed.


Assuntos
Neoplasias Pancreáticas , Tiossemicarbazonas , Humanos , Hidrazonas/farmacologia , Linhagem Celular Tumoral , Azulenos , Hidrazinas , Tiossemicarbazonas/farmacologia , Neoplasias Pancreáticas/tratamento farmacológico , Quelantes de Ferro/farmacologia , Ferro , Receptores da Transferrina , Ácidos Hidroxâmicos , Neoplasias Pancreáticas
6.
Biomed Pharmacother ; 154: 113582, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36055111

RESUMO

Mitochondria generate energy and building blocks required for cellular growth and function. The notion that mitochondria are not involved in the cancer growth has been challenged in recent years together with the emerging idea of mitochondria as a promising therapeutic target for oncologic diseases. Pentamethinium salts, cyan dyes with positively charged nitrogen on the benzothiazole or indole part of the molecule, were originally designed as mitochondrial probes. In this study, we show that pentamethinium salts have a strong effect on mitochondria, suppressing cancer cell proliferation and migration. This is likely linked to the strong inhibitory effect of the salts on dihydroorotate dehydrogenase (DHODH)-dependent respiration that has a key role in the de novo pyrimidine synthesis pathway. We also show that pentamethinium salts cause oxidative stress, redistribution of mitochondria, and a decrease in mitochondria mass. In conclusion, pentamethinium salts present novel anti-cancer agents worthy of further studies.


Assuntos
Neoplasias , Oxirredutases atuantes sobre Doadores de Grupo CH-CH , Di-Hidro-Orotato Desidrogenase , Humanos , Mitocôndrias/metabolismo , Neoplasias/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/metabolismo , Respiração , Sais/metabolismo
7.
Pharmaceutics ; 14(8)2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-36015338

RESUMO

IL-6 signaling is involved in the pathogenesis of a number of serious diseases, including chronic inflammation and cancer. Targeting of IL-6 receptor (IL-6R) by small molecules is therefore an intensively studied strategy in cancer treatment. We describe the design, synthesis, and characteristics of two new bis-pentamethinium salts 5 and 6 (meta and para) bearing indole moieties. Molecular docking studies showed that both compounds have the potential to bind IL-6R (free energy of binding -9.5 and -8.1 kcal/mol). The interaction with IL-6R was confirmed using microscale thermophoresis analyses, which revealed that both compounds had strong affinity for the IL-6R (experimentally determined dissociation constants 26.5 ± 2.5 nM and 304 ± 27.6 nM, respectively). In addition, both compounds were cytotoxic for a broad spectrum of cancer cell lines in micromolar concentrations, most likely due to their accumulation in mitochondria and inhibition of mitochondrial respiration. In summary, the structure motif of bis-pentamethinium salts represents a promising starting point for the design of novel multitargeting compounds with the potential to inhibit IL-6 signaling and simultaneously target mitochondrial metabolism in cancer cells.

8.
Biochem Biophys Res Commun ; 588: 182-186, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-34968794

RESUMO

Variegate porphyria is caused by mutations in the protoporphyrinogen oxidase IX (PPOX, EC 1.3.3.4) gene, resulting in reduced overall enzymatic activity of PPOX in human tissues. Recently, we have identified the His333Arg mutation in the PPOX protein (PPOX(H333R)) as a putative founder mutation in the Moroccan Jewish population. Herein we report the molecular characterization of PPOX(H333R) in vitro and in cells. Purified recombinant PPOX(H333R) did not show any appreciable enzymatic activity in vitro, corroborating the clinical findings. Biophysical experiments and molecular modeling revealed that PPOX(H333R) is not folded properly and fails to adopt its native functional three-dimensional conformation due to steric clashes in the vicinity of the active site of the enzyme. On the other hand, PPOX(H333R) subcellular distribution, as evaluated by live-cell confocal microscopy, is unimpaired suggesting that the functional three-dimensional fold is not required for efficient transport of the polypeptide chain into mitochondria. Overall, the data presented here provide molecular underpinnings of the pathogenicity of PPOX(H333R) and might serve as a blueprint for deciphering whether a given PPOX variant represents a disease-causing mutation.


Assuntos
Flavoproteínas/genética , Proteínas Mitocondriais/genética , Mutação/genética , Protoporfirinogênio Oxidase/genética , Sequência de Aminoácidos , Fenômenos Biofísicos , Linhagem Celular , Estabilidade Enzimática , Flavoproteínas/química , Flavoproteínas/isolamento & purificação , Humanos , Cinética , Proteínas Mitocondriais/química , Proteínas Mitocondriais/isolamento & purificação , Modelos Moleculares , Multimerização Proteica , Protoporfirinogênio Oxidase/química , Protoporfirinogênio Oxidase/isolamento & purificação , Frações Subcelulares/metabolismo , Temperatura
9.
Pharmaceutics ; 13(11)2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34834295

RESUMO

Designing optimal (neo)adjuvant therapy is a crucial aspect of the treatment of non-small-cell lung carcinoma (NSCLC). Standard methods of chemotherapy, radiotherapy, and immunotherapy represent effective strategies for treatment. However, in some cases with high metastatic activity and high levels of circulating tumour cells (CTCs), the efficacy of standard treatment methods is insufficient and results in treatment failure and reduced patient survival. CTCs are seen not only as an isolated phenomenon but also a key inherent part of the formation of metastasis and a key factor in cancer death. This review discusses the impact of NSCLC therapy strategies based on a meta-analysis of clinical studies. In addition, possible therapeutic strategies for repression when standard methods fail, such as the administration of low-toxicity natural anticancer agents targeting these phenomena (curcumin and flavonoids), are also discussed. These strategies are presented in the context of key mechanisms of tumour biology with a strong influence on CTC spread and metastasis (mechanisms related to tumour-associated and -infiltrating cells, epithelial-mesenchymal transition, and migration of cancer cells).

10.
Ceska Gynekol ; 86(2): 140-147, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34020563

RESUMO

INTRODUCTION: During the 30th symposium of assisted reproduction held on November 11, 2020 in Brno, the solved problems in reproductive medicine in the Czech Republic in 2020 were presented. The selected topics have concerned not only current issues in the field of clinical embryology and genetics as well as gynecology, but also legislation and ethics. Discussed topics: 1. How much time does the doctor have in the CAR (centrum of assisted reproduction) outpatient clinic per patient and how does the embryologist communicate with clients? 2. Reproduction and PGT-M in oncology patients and patients at risk with hereditary oncogenic mutations. 3. Non-invasive genetic testing of embryos from culture medium. 4. Genome editing. 5. What is the need to monitor hormonal levels in stimulation protocols? 6. Monitoring and embryo selection for transfer/kryo. 7. Is it time to change the law on donor remuneration? METHODS: The topics were prepared in advance by authorized members of our company with the task of elaborating theses, which they presented in a separate conference block. The presentation and the discussion were broadcast directly from the broadcast studio at Hotel International via an online connection. After the conference, all discussion topics and comments were incorporated. CONCLUSION: The work presents the state of the solved problems of reproductive medicine in the Czech Republic.


Assuntos
Medicina Reprodutiva , República Tcheca , Testes Genéticos , Humanos , Reprodução
11.
Int J Mol Sci ; 22(2)2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-33440733

RESUMO

Flavonoids are common plant natural products able to suppress ROS-related damage and alleviate oxidative stress. One of key mechanisms, involved in this phenomenon is chelation of transition metal ions. From a physiological perspective, iron is the most significant transition metal, because of its abundance in living organisms and ubiquitous involvement in redox processes. The chemical, pharmaceutical, and biological properties of flavonoids can be significantly affected by their interaction with transition metal ions, mainly iron. In this review, we explain the interaction of various flavonoid structures with Fe(II) and Fe(III) ions and critically discuss the influence of chelated ions on the flavonoid biochemical properties. In addition, specific biological effects of their iron metallocomplexes, such as the inhibition of iron-containing enzymes, have been included in this review.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Complexos de Coordenação/química , Flavonoides/química , Ferro/química , Animais , Quelantes/química , Quelantes/farmacologia , Heme/química , Humanos , Íons/química , Íons/metabolismo , Estrutura Molecular , Ligação Proteica , Relação Estrutura-Atividade
12.
Chem Biol Drug Des ; 97(2): 305-314, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32854159

RESUMO

Proton pump inhibitors, such as omeprazole, pantoprazole and lansoprazole, are an important group of clinically used drugs. Generally, they are considered safe without direct toxicity. Nevertheless, their long-term use can be associated with a higher risk of some serious pathological states (e.g. amnesia and oncological and neurodegenerative states). It is well known that dysregulation of the metabolism of transition metals (especially iron ions) plays a significant role in these pathological states and that the above drugs can form complexes with metal ions. However, to the best of our knowledge, this phenomenon has not yet been described in water systems. Therefore, we studied the interaction between these drugs and transition metal ions in the surrounding water environment (water/DMSO, 99:1, v/v) by absorption spectroscopy. In the presence of Fe(III), a strong redshift was observed, and more importantly, the affinities of the drugs (represented as binding constants) were strong enough, especially in the case of omeprazole, so that the formation of a metallocomplex cannot be excluded during the explanation of their side effects.


Assuntos
Complexos de Coordenação/química , Lansoprazol , Inibidores da Bomba de Prótons/química , Espectrofotometria , Água/química , Compostos Férricos/química , Lansoprazol/química , Omeprazol/química , Pantoprazol/química , Elementos de Transição/química
13.
Mol Hum Reprod ; 26(4): 269-276, 2020 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-32011698

RESUMO

Chromosomal mosaicism detected during preimplantation genetic testing for aneuploidy (PGT-A) and its impact on embryo implantation have been widely discussed, and healthy live births from mosaic embryos were reported by many groups. On the other hand, only very few studies have focused on segmental chromosome aneuploidies and their clinical impact. Eighty-nine embryos with various PGT-A results (trophectoderm 1: TE1) were re-analysed using a second trophectoderm biopsy (TE2) and the rest of the embryo (RE) for testing. Of 19 euploid TE1 biopsies, 18 were concordant across TE2 and RE. Similarly, whole chromosomal aneuploidies were concordant in 59 of 62 TE1-TE2 and 58 TE1-RE. In contrast, from 31 segmental aneuploidies detected in TE1, only 15 were observed again in TE2 and 14 in RE. If a TE1 segmental abnormality appeared again in TE2, it was almost always present in RE (17/18) as well. Moreover, when a TE1 segmental abnormality was not detected in TE2, in 12 out of 13 cases RE was also unaffected. Similarly, only 1 of 26 TE1 whole chromosome mosaics were repeated in TE2 and 7 in RE. Our study confirms that euploid and whole chromosomal aneuploidy results are highly predictive of the embryo. In contrast, mosaicism has a very low concordance rate. Most importantly, re-biopsy of embryos with segmental aneuploidies demonstrated that they are mostly not uniform across the embryo. Finally, in the case of segmental aneuploidy, the second biopsy enables an accurate prediction of the real status of the embryo and could be offered to patients undergoing PGT-A.


Assuntos
Aneuploidia , Embrião de Mamíferos , Testes Genéticos/métodos , Diagnóstico Pré-Implantação/métodos , Biópsia , Feminino , Humanos , Masculino , Mosaicismo , Reprodutibilidade dos Testes
14.
Reproduction ; 147(2): 231-40, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24277869

RESUMO

It has been recently shown in mice that sperm undergo acrosome reaction (AR) by passing through cumulus cells; furthermore, the acrosome-reacted sperm can bind to zona pellucida and consequently fertilise the egg. During AR, the relocation of the primary fusion protein IZUMO1 into the equatorial segment is crucial for sperm-egg fusion. There is a high rate of spontaneous AR in rodents, with up to 60% in promiscuous species. The aim of this study was to clarify whether the IZUMO1 relocation in sperm after spontaneous and induced AR is the same, and whether there is a correlation between the speed of IZUMO1 relocation and species-specific mating behaviour in field mice. Immunofluorescent detection of IZUMO1 dynamics during the in vitro capacitation, spontaneous, calcium ionophore and progesterone-induced AR was monitored. Our results show that during spontaneous AR, there is a clear IZUMO1 relocation from the acrosomal cap to the equatorial segment, and further over the whole sperm head. In addition, there is positive tail tyrosine phosphorylation (TyrP) associated with hyperactive motility. Moreover, the beginning and the progress of IZUMO1 relocation and tail TyrP positively correlate with the level of promiscuity and the acrosome instability in promiscuous species. The findings that crucial molecular changes essential for sperm-egg fusion represented by dynamic movements of IZUMO1 also happen during spontaneous AR are vital for understanding fertilisation in mice.


Assuntos
Reação Acrossômica/fisiologia , Imunoglobulinas/metabolismo , Proteínas de Membrana/metabolismo , Murinae/fisiologia , Espermatozoides/química , Espermatozoides/fisiologia , Acrossomo/química , Reação Acrossômica/efeitos dos fármacos , Animais , Imunoglobulinas/análise , Masculino , Proteínas de Membrana/análise , Camundongos , Camundongos Endogâmicos BALB C , Progesterona/farmacologia , Comportamento Sexual Animal , Especificidade da Espécie , Capacitação Espermática , Interações Espermatozoide-Óvulo/fisiologia , Zona Pelúcida/metabolismo
15.
Mol Genet Metab ; 107(3): 611-3, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22959829

RESUMO

We report on the seventh known patient with S-adenosylhomocysteine hydrolase (SAHH) deficiency presenting at birth with features resembling phosphomannomutase 2 (PMM2-CDG Ia) deficiency. Plasma methionine and total homocysteine levels were normal at 2 months and increased only after the 8th month of age. SAHH deficiency was confirmed at 4.5 years of age by showing decreased SAHH activity (11% in both erythrocytes and fibroblasts), and compound heterozygosity for a known mutation c.145C>T (p.R49C) and a novel variant c.211G>A (p.G71S) in the AHCY gene. Retrospective analysis of clinical features revealed striking similarities between SAHH deficiency and the PMM2-CDG Ia.


Assuntos
Adenosil-Homocisteinase/deficiência , Adenosil-Homocisteinase/genética , Defeitos Congênitos da Glicosilação/diagnóstico , Mutação , Diagnóstico Diferencial , Eritrócitos/enzimologia , Eritrócitos/patologia , Feminino , Fibroblastos/enzimologia , Fibroblastos/patologia , Heterozigoto , Homocisteína/sangue , Humanos , Recém-Nascido , Metionina/sangue , Fosfotransferases (Fosfomutases)/deficiência
16.
Hum Reprod ; 26(11): 3173-80, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21908463

RESUMO

BACKGROUND: Several randomized controlled trials have not shown a benefit from preimplantation genetic screening (PGS) biopsy of cleavage-stage embryos and assessment of up to 10 chromosomes for aneuploidy. Therefore, a proof-of-principle study was planned to determine the reliability of alternative form of PGS, i.e. PGS by polar body (PB) biopsy, with whole genome amplification and microarray-based comparative genomic hybridization (array CGH) analysis. METHODS: In two centres, all mature metaphase II oocytes from patients who consented to the study were fertilized by ICSI. The first and second PBs (PB1and PB2) were biopsied and analysed separately for chromosome copy number by array CGH. If either or both of the PBs were found to be aneuploid, the corresponding zygote was then also processed by array CGH for concordance analysis. RESULTS: Both PBs were biopsied from a total of 226 zygotes from 42 cycles (average 5.5 per cycle; range 1-15) in 41 couples with an average maternal age of 40.0 years. Of these, the ploidy status of the zygote could be predicted in 195 (86%): 55 were euploid (28%) and 140 were aneuploid (72%). With only one exception, there was at least one predicted aneuploid zygote in each cycle and in 19 out of 42 cycles (45%), all zygotes were predicted to be aneuploid. Fresh embryos were transferred in the remaining 23 cycles (55%), and one frozen transfer was done. Eight patients had a clinical pregnancy of which seven were evolutive (ongoing pregnancy rates: 17% per cycle and 30% per transfer). The ploidy status of 156 zygotes was successfully analysed by array CGH: 38 (24%) were euploid and 118 (76%) were aneuploid. In 138 cases complete information was available on both PBs and the corresponding zygotes. In 130 (94%), the ploidy status of the zygote was concordant with the ploidy status of the PBs and in 8 (6%), the results were discordant. CONCLUSIONS: This proof-of-principle study indicates that the ploidy of the zygote can be predicted with acceptable accuracy by array CGH analysis of both PBs.


Assuntos
Hibridização Genômica Comparativa/métodos , Oócitos/citologia , Corpos Polares/citologia , Injeções de Esperma Intracitoplásmicas/métodos , Adulto , Biópsia/métodos , Cromossomos , Cromossomos Artificiais Bacterianos , Transferência Embrionária , Europa (Continente) , Feminino , Humanos , Masculino , Idade Materna , Hibridização de Ácido Nucleico , Análise de Sequência com Séries de Oligonucleotídeos , Ploidias , Gravidez , Taxa de Gravidez , Diagnóstico Pré-Implantação/métodos
17.
Hum Reprod ; 26(11): 3181-5, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21908464

RESUMO

BACKGROUND: The purpose of this study was to assess the technical aspects related to polar body (PB) biopsy, which might have an influence on the results of the microarray comparative genomic hybridization analysis. Furthermore, a comparison was made between two biopsy methods (mechanical and laser). METHODS: Biopsy of the first and second PB (PB1 and PB2) was performed by mechanical- or laser-assisted biopsy in two different IVF centres. PBs were separately amplified by whole genome amplification. RESULTS: The method of biopsy, mechanical or laser had no influence on the proportion of successfully biopsied oocytes. Especially, for the PB2, the timing of biopsy after ICSI was directly correlated to amplification efficiency. CONCLUSIONS: Special care has to be taken with respect to the timing of biopsy of the PB2. Mechanical- and laser-assisted biopsy give the same performance in terms of diagnostic efficiency.


Assuntos
Cromossomos/ultraestrutura , Hibridização Genômica Comparativa/métodos , Oócitos/citologia , Corpos Polares/citologia , Injeções de Esperma Intracitoplásmicas/métodos , Aneuploidia , Biópsia/métodos , Células do Cúmulo/citologia , DNA/genética , Feminino , Técnicas Genéticas , Humanos , Masculino , Hibridização de Ácido Nucleico , Análise de Sequência com Séries de Oligonucleotídeos , Técnicas de Reprodução Assistida
18.
Hum Reprod ; 25(4): 821-3, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20124394

RESUMO

Since 2004, there have been 11 randomized controlled trials (RCTs) mainly for advanced maternal age (AMA), which have shown no benefit of performing preimplantation genetic screening (PGS). Ten of the RCTs have been performed at the cleavage stage and one at the blastocyst stage. It is probable that the high levels of chromosomal mosaicism at cleavage stages, which may result in the tested cell not being representative of the embryo, and the inability to examine all of the chromosomes using fluorescence in situ hybridization, have contributed to the lack of positive outcome from the RCTs. We suggest that future RCTs should examine alternative biopsy timing (polar body and/or trophectoderm biopsy), and should apply technologies that allow more comprehensive testing to include all chromosomes (microarray-based testing) to determine if PGS shows an improvement in delivery rate. Currently there is no evidence that routine PGS is beneficial for patients with AMA and conclusive data (RCTs) on repeated miscarriage, implantation failure and severe male factor are missing. To evaluate benefits of PGS, an ESHRE trial has recently been started on patients with AMA using polar body biopsy and array-comparative genomic hybridization, which should bring more information on this patient group in the near future.


Assuntos
Diagnóstico Pré-Implantação/tendências , Adulto , Comitês Consultivos , Biópsia/métodos , Fase de Clivagem do Zigoto/citologia , Hibridização Genômica Comparativa , Europa (Continente) , Feminino , Humanos , Recém-Nascido , Infertilidade/genética , Infertilidade/terapia , Masculino , Idade Materna , Gravidez , Diagnóstico Pré-Implantação/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto , Sociedades Médicas
19.
Neuro Endocrinol Lett ; 30(4): 501-5, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20010501

RESUMO

BACKGROUND: IGF-I gene polymorphisms might alter IGF-I level resulting in decreased foetal and postnatal growth and increased risk for diabetes mellitus type 2 and cardiovascular diseases in adulthood. OBJECTIVES: We analyzed the association between Cytosine-Adenosine (CA)10-24 repeats polymorphism in promoter region of the IGF-I gene and early growth in infants with birth weight appropriate for gestational age (AGA) and small for gestational age (SGA). DESIGN AND METHODS: All neonates were born at term, 196 of them were AGA and 26 SGA. Blood for DNA analyses was obtained from placental part of umbilical vein. Genotyping was performed using fragment analyses of IGF-I gene promoter region. The data about postnatal growth in the group of AGA children were obtained at the age of 18 months, in SGA children at 12 months. RESULTS: No differences in the frequency of wild type allele with (CA)19 repeats and polymorphisms with (CA)<19 or (CA)>19 repeats were observed between AGA and SGA children. The average birth weight and length in AGA wild type (CA)19 homozygotes were lower in comparison with AGA carriers of various (CA)n polymorphisms but all observed anthropometric differences disappeared at the age of 18 months. In SGA children, no differences were found between number of (CA)n repeats and anthropometric parameters both at birth and at the age of 12 months. CONCLUSIONS: Although (CA)n repeats polymorphism in IGF-I gene might affect prenatal growth in AGA children, our results have not shown any impact of variable number of (CA) n repeats in IGF-I gene on postnatal growth.


Assuntos
Desenvolvimento Infantil/fisiologia , Recém-Nascido Pequeno para a Idade Gestacional/crescimento & desenvolvimento , Recém-Nascido Pequeno para a Idade Gestacional/fisiologia , Fator de Crescimento Insulin-Like I/genética , Polimorfismo Genético , Adenosina , Peso ao Nascer/genética , Estatura/genética , Citosina , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Regiões Promotoras Genéticas/genética , Sequências Repetitivas de Ácido Nucleico
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