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1.
Front Endocrinol (Lausanne) ; 13: 953431, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36034425

RESUMO

Functional hypothalamic amenorrhea (FHA) is a temporary infertility characterized by the suppression of the hypothalamic-pituitary-gonadal (HPG) axis, induced by the inhibition of the hypothalamic pulsatile secretion of the gonadotropin-releasing hormone (GnRH), in the presence of stressors, including eating disorders, excessive exercise, and psychological distress. Although the stressful factors that may lead to FHA are well-established, little is known about the inter-individual variability in response to stress and the consequent inhibition of the HPG axis. Not all women, indeed, manifest FHA in presence of stressful conditions. Recent studies highlighted a genetic contribution to FHA. Rare or polymorphic variants in genes that control the development and/or function of GnRH neurons may contribute, indeed, to the adaptability of the reproductive axis to stress factors. Also epigenetic changes have been associated with different pathways involved in the HPG axis and therefore, take part in FHA and confer a personal predisposition to anovulation consequent to a stressful event, or represent biological markers of response to stress. This review summarizes recent advances in the identification of the contribution of (epi)genetics to FHA and to long-term complications of functional amenorrhea, and reports insights into the involvement of additional genetic loci in FHA development on the bases of the clinical and molecular overlap with other gynecological and/or psychological conditions. Finally, we describe the promising application of induced pluripotent stem cells (iPSCs) as a new approach to investigate the molecular pathways involved in FHA.


Assuntos
Amenorreia , Doenças Hipotalâmicas , Epigênese Genética , Feminino , Hormônio Liberador de Gonadotropina , Humanos , Reprodução
3.
Epigenetics ; 13(9): 897-909, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30221575

RESUMO

The identification of multilocus imprinting disturbances (MLID) appears fundamental to uncover molecular pathways underlying imprinting disorders (IDs) and to complete clinical diagnosis of patients. However, MLID genetic associated mechanisms remain largely unknown. To characterize MLID in Beckwith-Wiedemann (BWS) and Silver-Russell (SRS) syndromes, we profiled by MassARRAY the methylation of 12 imprinted differentially methylated regions (iDMRs) in 21 BWS and 7 SRS patients with chromosome 11p15.5 epimutations. MLID was identified in 50% of BWS and 29% of SRS patients as a maternal hypomethylation syndrome. By next-generation sequencing, we searched for putative MLID-causative mutations in genes involved in methylation establishment/maintenance and found two novel missense mutations possibly causative of MLID: one in NLRP2, affecting ADP binding and protein activity, and one in ZFP42, likely leading to loss of DNA binding specificity. Both variants were paternally inherited. In silico protein modelling allowed to define the functional effect of these mutations. We found that MLID is very frequent in BWS/SRS. In addition, since MLID-BWS patients in our cohort show a peculiar pattern of BWS-associated clinical signs, MLID test could be important for a comprehensive clinical assessment. Finally, we highlighted the possible involvement of ZFP42 variants in MLID development and confirmed NLRP2 as causative locus in BWS-MLID.


Assuntos
Síndrome de Beckwith-Wiedemann/genética , Cromossomos Humanos Par 15/genética , Metilação de DNA , Impressão Genômica , Síndrome de Silver-Russell/genética , Proteínas Adaptadoras de Transdução de Sinal/química , Proteínas Adaptadoras de Transdução de Sinal/genética , Adolescente , Proteínas Reguladoras de Apoptose , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Fatores de Transcrição Kruppel-Like/química , Fatores de Transcrição Kruppel-Like/genética , Masculino , Mutação de Sentido Incorreto , Adulto Jovem
4.
Clin Genet ; 91(2): 233-246, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27716927

RESUMO

Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome, also referred to as Müllerian agenesis, is the second most common cause of primary amenorrhea. It is characterized by congenital absence of the uterus, cervix, and the upper part of the vagina in otherwise phenotypically normal 46,XX females. MRKH syndrome has an incidence of about 1 in 4,500-5,000 newborn females and it is generally divided into two subtypes: MRKH type 1, in which only the upper vagina, cervix and the uterus are affected, and MRKH type 2, which is associated with additional malformations generally affecting the renal and skeletal systems, and also includes MURCS (MÜllerian Renal Cervical Somite) characterized by cervico-thoracic defects. MRKH syndrome is mainly sporadic; however, familial cases have been described indicating that, at least in a subset of patients, MRKH may be an inherited disorder. The syndrome appears to demonstrate an autosomal dominant inheritance pattern, with incomplete penetrance and variable expressivity. The etiology of MRKH syndrome is still largely unknown, probably because of its intrinsic heterogeneity. Several candidate causative genes have been investigated, but to date only WNT4 has been associated with MRKH with hyperandrogenism. This review summarizes and discusses the clinical features and details progress to date in understanding the genetics of MRKH syndrome.


Assuntos
Transtornos 46, XX do Desenvolvimento Sexual/genética , Anormalidades Múltiplas/genética , Amenorreia/genética , Anormalidades Congênitas/genética , Ductos Paramesonéfricos/anormalidades , Proteína Wnt4/genética , Transtornos 46, XX do Desenvolvimento Sexual/fisiopatologia , Anormalidades Múltiplas/patologia , Amenorreia/fisiopatologia , Colo do Útero/patologia , Anormalidades Congênitas/fisiopatologia , Feminino , Humanos , Hiperandrogenismo/genética , Hiperandrogenismo/patologia , Ductos Paramesonéfricos/fisiopatologia , Penetrância , Útero/patologia , Vagina/patologia
5.
Forensic Sci Int Genet ; 25: 63-72, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27500650

RESUMO

Since 1992, the Spanish and Portuguese-Speaking Working Group of the ISFG (GHEP-ISFG) has been organizing annual Intercomparison Exercises (IEs) coordinated by the Quality Service at the National Institute of Toxicology and Forensic Sciences (INTCF) from Madrid, aiming to provide proficiency tests for forensic DNA laboratories. Each annual exercise comprises a Basic (recently accredited under ISO/IEC 17043: 2010) and an Advanced Level, both including a kinship and a forensic module. Here, we show the results for both autosomal and sex-chromosomal STRs, and for mitochondrial DNA (mtDNA) in two samples included in the forensic modules, namely a mixture 2:1 (v/v) saliva/blood (M4) and a mixture 4:1 (v/v) saliva/semen (M8) out of the five items provided in the 2014 GHEP-ISFG IE. Discrepancies, other than typos or nomenclature errors (over the total allele calls), represented 6.5% (M4) and 4.7% (M8) for autosomal STRs, 15.4% (M4) and 7.8% (M8) for X-STRs, and 1.2% (M4) and 0.0% (M8) for Y-STRs. Drop-out and drop-in alleles were the main cause of errors, with laboratories using different criteria regarding inclusion of minor peaks and stutter bands. Commonly used commercial kits yielded different results for a micro-variant detected at locus D12S391. In addition, the analysis of electropherograms revealed that the proportions of the contributors detected in the mixtures varied among the participants. In regards to mtDNA analysis, besides important discrepancies in reporting heteroplasmies, there was no agreement for the results of sample M4. Thus, while some laboratories documented a single control region haplotype, a few reported unexpected profiles (suggesting contamination problems). For M8, most laboratories detected only the haplotype corresponding to the saliva. Although the GHEP-ISFG has already a large experience in IEs, the present multi-centric study revealed challenges that still exist related to DNA mixtures interpretation. Overall, the results emphasize the need for further research and training actions in order to improve the analysis of mixtures among the forensic practitioners.


Assuntos
Cromossomos Humanos X , Cromossomos Humanos Y , Impressões Digitais de DNA , DNA Mitocondrial/genética , Laboratórios/normas , Repetições de Microssatélites , Amelogenina/genética , Análise Química do Sangue , Feminino , Genética Forense , Marcadores Genéticos , Haplótipos , Humanos , Masculino , Saliva/química , Sêmen/química
6.
Blood Cancer J ; 2: e96, 2012 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-23178508

RESUMO

Small nucleolar RNAs (snoRNAs) and small Cajal body-specific RNAs (scaRNAs) are non-coding RNAs involved in the maturation of other RNA molecules and generally located in the introns of host genes. It is now emerging that altered sno/scaRNAs expression may have a pathological role in cancer. This study elucidates the patterns of sno/scaRNAs expression in multiple myeloma (MM) by profiling purified malignant plasma cells from 55 MMs, 8 secondary plasma cell leukemias (sPCLs) and 4 normal controls. Overall, a global sno/scaRNAs downregulation was found in MMs and, even more, in sPCLs compared with normal plasma cells. Whereas SCARNA22 resulted the only sno/scaRNA characterizing the translocation/cyclin D4 (TC4) MM, TC2 group displayed a distinct sno/scaRNA signature overexpressing members of SNORD115 and SNORD116 families located in a region finely regulated by an imprinting center at 15q11, which, however, resulted overall hypomethylated in MMs independently of the SNORD115 and SNORD116 expression levels. Finally, integrative analyses with available gene expression and genome-wide data revealed the occurrence of significant sno/scaRNAs/host genes co-expression and the putative influence of allelic imbalances on specific snoRNAs expression. Our data extend the current view of sno/scaRNAs deregulation in cancer and add novel information to the bio-molecular complexity of plasma cell dyscrasias.

7.
Oncogene ; 30(27): 3096-103, 2011 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-21478910

RESUMO

The p53 transcription factor has a critical role in cell stress response and in tumor suppression. Wild-type p53 protein is a growth modulator and its inactivation is a critical event in malignant transformation. It has been recently demonstrated that wild-type p53 has developmental and differentiation functions. Indeed an over-expression of p53 in tumor cells induces asymmetrical division avoiding self-renewal of cancer stem cells (CSCs) and instead promoting their differentiation. In this study, 28 human breast carcinomas have been analyzed for expression of wild-type p53 and of a pool of non-clustered homeobox genes. We demonstrated that orthodenticle homolog 1 gene (OTX1) is transcribed in breast cancer. We established that the p53 protein directly induces OTX1 expression by acting on its promoter. OTX1 has been described as a critical molecule for axon refinement in the developing cerebral cortex of mice, and its activity in breast cancer suggests a synergistic function with p53 in CSC differentiation. Wild-type p53 may regulate cellular differentiation by an alternative pathway controlling OTX1 signaling only in breast cancer cells and not in physiological conditions.


Assuntos
Neoplasias da Mama/metabolismo , Regulação Neoplásica da Expressão Gênica/fisiologia , Fatores de Transcrição Otx/genética , Proteína Supressora de Tumor p53/fisiologia , Neoplasias da Mama/genética , Feminino , Humanos
8.
Placenta ; 32(1): 44-50, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21036394

RESUMO

Iron (Fe) deficiency in pregnancy is associated to low birth weight and premature delivery while in adults it can result in increased blood pressure and cardiovascular disease. Cellular Fe uptake is mediated by the Transferrin Receptor 1 (TFRC), located in the trophoblast membranes. Here, we measured TFRC mRNA expression (Real Time PCR) and TFRC protein expression and localization (Western Blotting and immunohistochemistry) in IUGR compared to control placentas. A total of 50 IUGR and 56 control placentas were studied at the time of elective cesarean section. IUGR was defined by ultrasound in utero, and confirmed by birth weight <10th percentile. Three different severity groups were identified depending on the umbilical artery pulsatility index and fetal heart rate. TFRC mRNA expression was significantly lower in IUGR placentas compared to controls (p < 0.05), and this was confirmed for TFRC protein levels. In both experiments the most severe IUGR group presented lower expression compared to the other groups, and this was also related to umbilical venous oxygen levels. TFRC protein localization in the villous trophoblast did not differ in the groups, and was predominantly present in the syncytiotrophoblast. In conclusion, these are the first observations about TFRC expression in human IUGR placentas, demonstrating its significant decrease in IUGR vs controls. Thus, Fe transport could be limited in IUGR placentas. Further studies are needed to study components of the placental Fe transport system and to clarify the regulation mechanisms involved in TFRC expression, possibly altered in IUGR placentas.


Assuntos
Retardo do Crescimento Fetal/genética , Retardo do Crescimento Fetal/metabolismo , Placenta/metabolismo , Receptores da Transferrina/genética , Receptores da Transferrina/metabolismo , Adulto , Gasometria , Estudos de Casos e Controles , Feminino , Retardo do Crescimento Fetal/sangue , Retardo do Crescimento Fetal/patologia , Humanos , Placenta/patologia , Gravidez/sangue , Gravidez/genética , Gravidez/metabolismo , Nascimento a Termo/genética , Nascimento a Termo/metabolismo , Distribuição Tecidual
9.
Hum Reprod ; 25(6): 1398-403, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20356899

RESUMO

BACKGROUND: It would be of value to identify ongoing spermatogenesis molecular markers which can predict successful sperm recovery in patients with non-obstructive azoospermia undergoing conventional or microsurgical testicular sperm extraction (TESE/microTESE). ESX1 is an X-linked homeobox gene expressed in testis, placenta, brain and lung in humans and specifically in pre- and post-meiotic germ cells of the testis in mice. METHODS: We investigated the sequence, expression (by RT-PCR) and epigenetic status (by promoter pyrosequencing) of ESX1 in testicular tissue samples, obtained from 81 azoospermic subjects in the context of surgical sperm extraction, to check a possible association between ESX1 alterations and impaired spermatogenesis, as determined by histological analysis. RESULTS: The ESX1 transcript was detected in 100% of cases diagnosed as obstructive azoospermia (33), hypospermatogenesis (18) and incomplete maturation arrest (MA) (2), and sperm recovery was also successful in 100% of these cases. ESX1 mRNA was also detected in 5 of 6 patients with incomplete Sertoli cell-only syndrome, in 4 of 6 subjects with complete MA but in only 3 of 16 cases of complete Sertoli cell-only syndrome (cSCOS), whereas sperm recovery was successful in 4 of 6, 2 of 6 and 5 of 16 of these patients, respectively. In cases of focal spermatogenesis, ESX1 expression and sperm retrieval were concordant in 14 of 19 (74%) cases subjected to TESE, but in only 3 of 11 (27%) men who underwent microTESE. With TESE, but not with microTESE, both samples originated from adjacent testicular areas. The pyrosequencing of the ESX1 CpG island revealed methylation levels that were significantly lower in ESX1 expressors when compared with non-expressors. CONCLUSIONS: ESX1 emerges as a potentially reliable spermatogenesis molecular marker, whose clinical value as a predictor of successful sperm retrieval warrants further studies.


Assuntos
Azoospermia/genética , Proteínas de Homeodomínio/genética , Espermatogênese/genética , Adulto , Biomarcadores , Metilação de DNA/genética , Expressão Gênica , Humanos , Masculino , Regiões Promotoras Genéticas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Motilidade dos Espermatozoides/genética , Recuperação Espermática
10.
Forensic Sci Int ; 196(1-3): 18-21, 2010 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-20080367

RESUMO

Drug testing in hair usually requires a rather complex sample treatment before drugs are amenable to analysis by either immunological and/or chromatographic coupled to mass spectrometry methods. Immunological methods applied are usually dedicated to hair analysis as analytes present in this matrix are not always the same present in urine. Comedical s.a.s. laboratories recently commercialized reagents (VMA-T) purposely designed for hair sample treatment which are compatible with current immunometric methods used for urine drug testing. This is possible as some analytes (6-MAM and cocaine) present in hair after sample treatment are converted to those detected in urine (morphine and benzoylecgonine). A correlation study for several drug classes performed in two laboratories with 32 clinical and 12 spiked drug free (controls) hair samples shows that implementation of the method on clinical chemistry analyzers is easy and that results obtained by different operators and instruments are comparable and reproducible. The main advantage of VMA-T method is the possibility to simultaneously extract from hair main drug classes, in a period of time lower than 2h and its compatibility with immunological methods applied in urine drug testing.


Assuntos
Cabelo/química , Entorpecentes/análise , Detecção do Abuso de Substâncias/métodos , Anfetaminas/análise , Canabinoides/análise , Cocaína/análise , Toxicologia Forense/métodos , Cromatografia Gasosa-Espectrometria de Massas , Alucinógenos/análise , Humanos , Imunoensaio , Indicadores e Reagentes , Metadona/análise , N-Metil-3,4-Metilenodioxianfetamina/análise
11.
Pediatr Med Chir ; 31(2): 65-71, 2009.
Artigo em Italiano | MEDLINE | ID: mdl-19642498

RESUMO

Many adult diseases seem to be associated with early nutrition and the subsequent growth pattern. Epidemiological studies hypotized that babies with intrauterine and/or neonatal growth retardation may be at greater risk of metabolic syndrome later in life. According to the Barker's "thrifty phenotype hypotesis" early malnutrition, whereas inducing physiological compensation by the promotion of early survival, appears to confer greater susceptibility to adults diseases. Epigenetics, that is the interindividual variation in DNA methylation patterns and chromatin remodelling, provide a potential explanation for how environmental factors can modify the risk for development of many common diseases. Beginning from animal models, many studies concerning early nutrition, epigenetic modifications and genes expression have been carried out. Maternal undernutrition during pregnancy, especially in the peri-implantation period, not only causes a prolonged growth retardation but also modifies the programming of biochemical mechanisms related to endocrine-metabolic control. Human studies have demonstrated the role played by IGF-1 as indicator of nutritional status and fetal/postnatal growth retardation. It has been reported that alterations in IGF axis, which predispose to adults diseases, may be due to an alterated epigenetic regulation that can modify IGF expression. Despite the critical inter-relation between early nutrition, growth, development, and subsequent health, there are few data on the influence of early nutrition on the modifications of the epigenetic gear. Furthermore it is hoped for a bigger attention to the early nutrition to prevent the development of diseases later in life.


Assuntos
Epigênese Genética , Regulação da Expressão Gênica no Desenvolvimento , Fator de Crescimento Insulin-Like II/genética , Fator de Crescimento Insulin-Like I/genética , Fenômenos Fisiológicos da Nutrição Pré-Natal/genética , Adulto , Animais , Medicina Baseada em Evidências , Feminino , Retardo do Crescimento Fetal/genética , Retardo do Crescimento Fetal/prevenção & controle , Marcadores Genéticos/genética , Humanos , Fenômenos Fisiológicos da Nutrição do Lactente/genética , Recém-Nascido , Desnutrição/genética , Desnutrição/prevenção & controle , Síndrome Metabólica/genética , Síndrome Metabólica/prevenção & controle , Fenótipo , Gravidez , Fatores de Risco , Transcrição Gênica
12.
Dig Liver Dis ; 41(7): 523-33, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18948067

RESUMO

BACKGROUND/AIMS: Incidence of cholangiocarcinoma is increasing worldwide, yet remaining highly aggressive and with poor prognosis. The mechanisms that drive cholangiocyte transition towards malignant phenotype are obscure. Cholangiocyte benign proliferation is subjected to a self-limiting mechanism based on the autocrine release of endogenous opioid peptides. Despite the presence of both, ligands interact with delta opioid receptor (OR), but not with microOR, with the consequent inhibition of cell growth. We aimed to verify whether cholangiocarcinoma growth is associated with failure of opioidergic regulation of growth control. METHODS: We evaluated the effects of OR selective agonists on cholangiocarcinoma cell proliferation, migration and apoptosis. Intracellular signals were also characterised. RESULTS: Activation of microOR, but not deltaOR, increases cholangiocarcinoma cell growth. Such an effect is mediated by ERK1/2, PI3K and Ca(2+)-CamKIIalpha cascades, but not by cAMP/PKA and PKCalpha. microOR activation also enhances cholangiocarcinoma cell migration and reduces death by apoptosis. The anti-apoptotic effect of microOR was PI3K dependent. CONCLUSIONS: Our data indicate that cholangiocarcinoma growth is associated with altered opioidergic regulation of cholangiocyte biology, thus opening new scenarios for future surveillance or early diagnostic strategies for cholangiocarcinoma.


Assuntos
Proliferação de Células , Colangiocarcinoma/patologia , Receptores Opioides delta/metabolismo , Receptores Opioides mu/metabolismo , Apoptose , Linhagem Celular Tumoral , Movimento Celular , Colangiocarcinoma/metabolismo , Humanos , Transdução de Sinais
14.
J Med Genet ; 44(4): 257-63, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17259293

RESUMO

BACKGROUND: The phenotypic variability in Beckwith-Wiedemann syndrome (BWS) reflects the genetic heterogeneity of the mechanism which by default leads to the deregulation of genes located at 11p15.5. Genotype-phenotype correlation studies have demonstrated an association between omphalocoele and CDKN1C/p57 mutations or hypermethylation. Paternal uniparental disomy 11 (pUPD11) has been described only in the mosaic condition with both uniparental and biparental cell lines, and no association with omphalocoele has been pointed out. METHODS: Two cases are presented here, in which a paternal segmental UPD11 was detected by molecular investigation of amniotic fluid cell cultures after the presence of apparently isolated omphalocoele was revealed in the fetuses by ultrasound scan. Further studies were performed on additional autoptic feto-placental tissues to characterise the distribution of the uniparental cell line and to unmask any biparental lineage in order to document in more detail the as yet unreported association between omphalocoele and pUPD11. RESULTS: Results on the UPD distribution profile showed that the abdominal organs have a predominant uniparental constitution. This condition could mimic the effect of CDKN1C/p57 inactivation, causing the omphalocoele. CONCLUSION: New genotype-phenotype correlations emerge from the investigated cases, suggesting that molecular analysis be extended to all cases with fetal omphalocoele in order to establish the incidence of pUPD11 in complete BWS and in monosymptomatic/mild forms.


Assuntos
Síndrome de Beckwith-Wiedemann/genética , Cromossomos Humanos Par 11/genética , Heterogeneidade Genética , Hérnia Umbilical/genética , Dissomia Uniparental/genética , Aborto Eugênico , Adulto , Amniocentese , Líquido Amniótico/citologia , Síndrome de Beckwith-Wiedemann/embriologia , Síndrome de Beckwith-Wiedemann/patologia , Células Cultivadas , Estudos de Coortes , Feminino , Genótipo , Hérnia Umbilical/diagnóstico por imagem , Hérnia Umbilical/embriologia , Humanos , Itália/epidemiologia , Cariotipagem , Repetições de Microssatélites , Fenótipo , Gravidez , Ultrassonografia Pré-Natal
15.
Placenta ; 26(1): 10-8, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15664406

RESUMO

A number of genetic and environmental factors are taken into account as responsible for intrauterine growth restriction (IUGR); nevertheless, the relevance of genetic alteration in IUGR aetiology remains to be determined. The aim of this study was to investigate using a combined cytogenetic-molecular approach, improved by a new application of QF-PCR method, the presence of mosaic chromosomal changes in fetal/placental samples from 12 pregnancies with unexplained severe IUGR. This multiple approach allowed us to reveal and quantify subtle chromosomal mosaicisms with less than 5% of trisomic cells even in cases in which cytogenetic and FISH analyses failed to reveal them. These are three pregnancies with a mosaic trisomy for chromosomes 7, 2 and 14; the former case presented matUPD7 and was previously described in this journal (Placenta 22 (2001) 813) in association with pre- and postnatal growth restriction. It is intriguing that chromosomes 7, 2 and 14 are known or suspected to harbour imprinted genes, so that an unbalanced gene dosage in a subset of cells during embryonic development could lead to an early impairment of placental function. Our findings indicate that extensive molecular and cytogenetic studies of IUGR fetal and placental tissues are necessary to reveal at least part of the heterogeneous genetic lesions implicated in IUGR phenotypes.


Assuntos
Cromossomos Humanos , Desenvolvimento Fetal/genética , Retardo do Crescimento Fetal/genética , Predisposição Genética para Doença , Mosaicismo/embriologia , Placenta , Adulto , Células Cultivadas , Bandeamento Cromossômico , Feminino , Retardo do Crescimento Fetal/diagnóstico por imagem , Retardo do Crescimento Fetal/etiologia , Fluorescência , Idade Gestacional , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Leucócitos Mononucleares , Masculino , Fenótipo , Placenta/patologia , Reação em Cadeia da Polimerase/métodos , Gravidez , Sequências de Repetição em Tandem/genética , Ultrassonografia
16.
Placenta ; 25(8-9): 753-7, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15450396

RESUMO

Intrauterine growth restriction (IUGR) is associated with significantly increased perinatal morbidity and mortality as well as cardiovascular disease and glucose intolerance in adult life. A number of disorders from genetic to metabolic, vascular, coagulative, autoimmune, as well as infectious, can influence fetal growth by damaging the placenta, leading to IUGR as a result of many possible fetal, placental and maternal disorders. Strict definitions of IUGR and of its severity are needed in order to eventually distinguish among different phenotypes, such as gestational age at onset, degree of growth restriction and presence of hypoxia. This report explores and reviews some of the most recent developments in both clinical and basic research on intrauterine growth restriction, by seeking mechanisms that involve genetic factors, utero-placental nutrient availability and vascular growth factors. New exciting findings on the genomic imprinting defects potentially associated with IUGR, and the placental anomalies associated with the decreased nutrient transport are summarized. Moreover, recent data on angiogenic growth factors as well as new information arising from application of gene chip technologies are discussed.


Assuntos
Retardo do Crescimento Fetal , Placenta/metabolismo , Placenta/patologia , Adulto , Indutores da Angiogênese/metabolismo , Feminino , Retardo do Crescimento Fetal/etiologia , Retardo do Crescimento Fetal/metabolismo , Retardo do Crescimento Fetal/patologia , Impressão Genômica , Humanos , Cooperação Internacional , Gravidez
17.
FEBS Lett ; 509(2): 323-6, 2001 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-11741610

RESUMO

This study describes for the first time the amphiphilicity of the protein moiety of proteoglycogen. Glycogenin but not proteoglycogen associates to phospholipid vesicles and forms by itself stable Gibbs and Langmuir monolayers at the air-buffer interface. The adsorption free energy (-6.7 kcal/mol) and the glycogenin collapse pressure (47 mN/m) are indicative of its high surface activity which can thermodynamically drive and retain the protein at the membrane interface to a maximum equilibrium adsorption surface pressure of 21 mN/m. The marked surface activity of glycogenin is further enhanced by its thermodynamically favorable penetration into zwitterionic and anionic phospholipids with a high cut-off surface pressure point above 30 mN/m. The strong association to phospholipid vesicles and the marked surface activity of glycogenin correspond to a high amphiphilic character which supports its spontaneous association to membrane interfaces, in which the de novo biosynthesis of glycogen was proposed to initiate.


Assuntos
Glucosiltransferases/química , Glicogênio/biossíntese , Glicoproteínas/química , Adsorção , Animais , Bovinos , Bicamadas Lipídicas , Fosfolipídeos , Coelhos , Propriedades de Superfície , Termodinâmica
18.
Am J Med Genet ; 104(4): 282-6, 2001 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11754060

RESUMO

A patient with microbrachycephaly, high forehead, long philtrum, thin upper lip, downturned corners of the mouth, low set ears with overlapping helix, fifth-finger clinodactyly, small hands and feet, bilateral transverse palmar crease, low total finger ridge count, hypotonia, severe growth and psychomotor delay, mild hypoplasia of corpus callosum, and Arnold-Chiari type 1 malformation is reported. The karyotype showed 46, XY, del(1)(q23q31.2). Coagulation factor V (F5, 1q23) and coagulation factor XIII (F13B, 1q31-q32.1) levels were normal. As expected, antithrombin III (AT3, 1q23-q25.1) serum level and activity were half of normal. We performed a review of the literature on proximal and intermediate deletion 1q syndrome, and we hypothesize the existence of only one 1q interstitial deletion syndrome, clinically characterized by ATIII deficiency.


Assuntos
Antitrombina III/metabolismo , Deleção Cromossômica , Cromossomos Humanos Par 1/genética , Adolescente , Antitrombina III/genética , Criança , Pré-Escolar , Bandeamento Cromossômico , Seguimentos , Haplótipos , Humanos , Lactente , Cariotipagem , Masculino , Síndrome
19.
Placenta ; 22(10): 813-21, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11718568

RESUMO

Maternal UPD of chromosome 7 is associated with pre- and postnatal growth retardation (IUGR, PNGR) and Silver-Russell syndrome (SRS [MIM 180860]). We report a case of IUGR in a newborn with SRS stigmata. Using combined haplotyping and cytogenetic-FISH studies we characterized the lymphocytes, umbilical cord and four placental cotyledons. The results are consistent with complete maternal isodisomy 7 and trisomy 7 mosaicism of post-zygotic origin. The trisomic cell line was prevalent in trophoblast cells from two placental cotyledons. Trisomy 7 of post-zygotic origin is a frequent finding, but maternal isodisomy 7, due to trisomic rescue has never been reported. PEG1/MEST expression was evaluated on placenta cDNA and a specific transcript was revealed only in the cotyledons with a high percentage of trisomic cells and the presence of the paternal chromosome 7 contribution, but not in the placental biopsies with maternal isodisomy 7. The histological features of the four placental fragments revealed that isodisomy 7 correlates with a pattern of cotyledonary hyper-ramification due to an increase of the branching angiogenesis, which could be the result of a defect of angiogenesis caused by the absence of PEG1 product. The severe hypo-ramification of the two cotyledons, showing trisomy 7 mosaicism, may be due to the triplicate dosage of genes on chromosome 7. The delayed fetal growth could be the phenotypic effect of the imbalance between imprinted and non-imprinted genes on chromosome 7 in the fetus or the result of abnormal placental function during pregnancy.


Assuntos
Cromossomos Humanos Par 7 , Expressão Gênica , Placenta/metabolismo , Proteínas/genética , Dissomia Uniparental/genética , Adulto , Vilosidades Coriônicas/ultraestrutura , Análise Citogenética , DNA/análise , Feminino , Retardo do Crescimento Fetal/genética , Idade Gestacional , Haplótipos , Humanos , Hibridização in Situ Fluorescente , Recém-Nascido , Linfócitos/química , Masculino , Placenta/patologia , Gravidez
20.
J Exp Psychol Learn Mem Cogn ; 27(6): 1430-50, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11713878

RESUMO

In a series of experiments, the authors investigated whether naming latencies for homophones (e.g., /nlambdan/) are a function of specific-word frequency (i.e., the frequency of nun) or a function of cumulative-homophone frequency (i.e., the sum of the frequencies of nun and none). Specific-word but not cumulative-homophone frequency affected picture-naming latencies. This result was obtained in 2 languages (English and Chinese). An analogous finding was obtained in a translation task, where bilingual speakers produced the English names of visually presented Spanish words. Control experiments ruled out that these results are an artifact of orthographic or articulatory factors, or of visual recognition. The results argue against the hypothesis that homophones share a common word-form representation, and support instead a model in which homophones have fully independent representations.


Assuntos
Linguística , Memória , Fala , Adulto , Feminino , Humanos , Masculino , Modelos Psicológicos , Multilinguismo , Medida da Produção da Fala
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