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1.
Biomed Pharmacother ; 174: 116531, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38574624

RESUMO

N-acylethanolamines (NAEs) are endogenous lipid-signalling molecules involved in inflammation and energy metabolism. The potential pharmacological effect of NAE association in managing inflammation-based metabolic disorders is unexplored. To date, targeting liver-adipose axis can be considered a therapeutic approach for the treatment of obesity and related dysfunctions. Here, we investigated the metabolic effect of OLALIAMID® (OLA), an olive oil-derived NAE mixture, in limiting liver and adipose tissue (AT) dysfunction of high-fat diet (HFD)-fed mice. OLA reduced body weight and fat mass in obese mice, decreasing insulin resistance (IR), as shown by homeostasis model assessment index, and leptin/adiponectin ratio, a marker of adipocyte dysfunction. OLA improved serum lipid and hepatic profile and the immune/inflammatory pattern of metainflammation. In liver of HFD mice, OLA treatment counteracted glucose and lipid dysmetabolism, restoring insulin signalling (phosphorylation of AKT and AMPK), and reducing mRNAs of key markers of fatty acid accumulation. Furthermore, OLA positively affected AT function deeply altered by HFD by reprogramming of genes involved in thermogenesis of interscapular brown AT (iBAT) and subcutaneous white AT (scWAT), and inducing the beigeing of scWAT. Notably, the NAE mixture reduced inflammation in iBAT and promoted M1-to-M2 macrophage shift in scWAT of obese mice. The tissue and systemic anti-inflammatory effects of OLA and the increased expression of glucose transporter 4 in scWAT contributed to the improvement of gluco-lipid toxicity and insulin sensitivity. In conclusion, we demonstrated that this olive oil-derived NAE mixture is a valid nutritional strategy to counteract IR and obesity acting on liver-AT crosstalk, restoring both hepatic and AT function and metabolism.


Assuntos
Adipócitos , Tecido Adiposo , Dieta Hiperlipídica , Etanolaminas , Resistência à Insulina , Fígado , Camundongos Endogâmicos C57BL , Obesidade , Animais , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Etanolaminas/farmacologia , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Camundongos , Dieta Hiperlipídica/efeitos adversos , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Camundongos Obesos , Metabolismo dos Lipídeos/efeitos dos fármacos
2.
Hum Genomics ; 17(1): 49, 2023 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-37303042

RESUMO

BACKGROUND: Individuals infected with SARS-CoV-2 vary greatly in their disease severity, ranging from asymptomatic infection to severe disease. The regulation of gene expression is an important mechanism in the host immune response and can modulate the outcome of the disease. miRNAs play important roles in post-transcriptional regulation with consequences on downstream molecular and cellular host immune response processes. The nature and magnitude of miRNA perturbations associated with blood phenotypes and intensive care unit (ICU) admission in COVID-19 are poorly understood. RESULTS: We combined multi-omics profiling-genotyping, miRNA and RNA expression, measured at the time of hospital admission soon after the onset of COVID-19 symptoms-with phenotypes from electronic health records to understand how miRNA expression contributes to variation in disease severity in a diverse cohort of 259 unvaccinated patients in Abu Dhabi, United Arab Emirates. We analyzed 62 clinical variables and expression levels of 632 miRNAs measured at admission and identified 97 miRNAs associated with 8 blood phenotypes significantly associated with later ICU admission. Integrative miRNA-mRNA cross-correlation analysis identified multiple miRNA-mRNA-blood endophenotype associations and revealed the effect of miR-143-3p on neutrophil count mediated by the expression of its target gene BCL2. We report 168 significant cis-miRNA expression quantitative trait loci, 57 of which implicate miRNAs associated with either ICU admission or a blood endophenotype. CONCLUSIONS: This systems genetics study has given rise to a genomic picture of the architecture of whole blood miRNAs in unvaccinated COVID-19 patients and pinpoints post-transcriptional regulation as a potential mechanism that impacts blood traits underlying COVID-19 severity. The results also highlight the impact of host genetic regulatory control of miRNA expression in early stages of COVID-19 disease.


Assuntos
COVID-19 , MicroRNAs , Humanos , COVID-19/genética , SARS-CoV-2/genética , Genômica , MicroRNAs/genética , RNA Mensageiro
3.
Life Sci ; 313: 121301, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36535405

RESUMO

AIMS: Bisphenol A (BPA) is an endocrine-disrupting chemical inducing several damages such as neurotoxicity, immunotoxicity, and metabolic disorders. Obesity is the main risk factor for the increased occurrence of metabolic alterations as well as mood disorders. Here, we investigated in obese mice the effects of BPA on anxiety-like behavior, associated with neuroinflammation and immune activation. MAIN METHODS: Male C57Bl/6J mice were divided into 4 groups: control group (STD) receiving chow diet and BPA vehicle; STD group treated with BPA (50 µg/kg/die); high-fat diet (HFD) group receiving BPA vehicle; HFD group treated with BPA. BPA treatment started 12 weeks after HFD feeding and lasted 3 weeks. KEY FINDINGS: The open field and elevated plus-maze tests showed in HFD + BPA group the worsening of HFD-induced anxiety-like behavior. The anxiogenic effects of BPA also emerged from hyperactivation of the hypothalamus-pituitary-adrenal gland axis, determined by the increased transcription of Crh and its receptor in the prefrontal cortex (PFC). Furthermore, BPA activated NLRP3 inflammasome and exacerbated the neuroinflammation induced by HFD, increasing IL-1ß, TNF-α and monocyte chemoattractant protein (MCP)-1 in PFC. Furthermore, it induced inflammation and monocyte recruitment in hypothalamus and amygdala. Contextually, BPA significantly amplified the immune activation caused by lipid overload as evidenced by the increased expression of TLR-4 and MCP-1 in the PFC and triggered mastocytosis in the hypothalamus rather than STD mice. SIGNIFICANCE: All these data show that sub-chronic BPA exposure represents an additional risk factor for mood disorders strictly related to obesity, enhancing neuroinflammation and immune activation triggered by HFD feeding.


Assuntos
Doenças Neuroinflamatórias , Animais , Masculino , Camundongos , Ansiedade/induzido quimicamente , Dieta Hiperlipídica/efeitos adversos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Obesidade/complicações , Córtex Pré-Frontal
4.
Diabetol Metab Syndr ; 13(1): 98, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34496965

RESUMO

BACKGROUND: Obesity-associated coronary heart disease (CHD) risk is higher in women than in men with type 2 diabetes (T2DM). Resistin, an adipokine secreted by adispose tissue, may contribute to this higher risk. AIMS: To explore the relationships among resistin levels and common inflammatory and endothelial dysfunction markers and CHD risk in obese post-menopausal T2DM women. METHODS: Serum levels of resistin, hsCRP, IL-6, Soluble vascular cell adhesion molecule (sVCAM), homocysteine (tHcy), HOMA-IR and metabolic parameters were determined in a group of 132 T2DM women with and without documented CHD and in 55 non-diabetic women. RESULTS: Resistin, sVCAM, IL-6 and tHcy levels were comparable in T2DM and controls. CHD women showed higher resistin, sVCAM and tHcy levels than those without CHD, and for resistin this difference remained significant after age-adjustment (P = 0.013); conversely hsCRP were ~ 2X higher in T2DM women than in controls (P = 0.0132) without any difference according to CHD history. At univariate analysis resistin levels were significantly associated with age, waist circumference, hypertension, tHcy, hsPCR, sVCAM, IL-6, HDL-cholesterol, triglycerides and creatinine levels, but only creatinine, triglycerides, hsCRP, IL-6 and sVCAM were independently associated to resistin levels at stepwise regression analysis. Resistin levels were independently associated to CHD, increasing the risk by 1.15 times (0.986-1.344 95% CI), together with age, tHcy, LDL-C and hypertension. CONCLUSIONS: Circulating resistin levels were comparable in obese/overweight T2DM and control women. In T2DM women, resistin levels correlated with markers of renal function, systemic inflammation and endothelial dysfunction and were independently associated with a higher CHD risk.

5.
Neoplasma ; 67(6): 1437-1446, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32787435

RESUMO

Radiomics focuses on extracting a large number of quantitative imaging features and testing both their correlation with clinical characteristics and their prognostic and predictive values. We propose a radiomic approach using magnetic resonance imaging (MRI) to decode the tumor phenotype and local recurrence in oropharyngeal squamous cell carcinoma (OPSCC). The contrast-enhanced T1-weighted sequences from baseline MRI examinations of OPSCC patients treated between 2008 and 2016 were retrospectively selected. Radiomic features were extracted using the IBEX software, and hiegrarchical clustering was applied to reduce features redundancy. The association of each radiomic feature with tumor grading and stage, HPV status, loco-regional recurrence within 2 years, considered as main endpoints, was assessed by univariate analysis and then corrected for multiple testing. Statistical analysis was performed with SAS/STAT® software. Thirty-two eligible cases were identified. For each patient, 1286 radiomic features were extracted, subsequently grouped into 16 clusters. Higher grading (G3 vs. G1/G2) was associated with lower values of GOH/65Percentile and GOH/85Percentile features (p=0.04 and 0.01, respectively). Positive HPV status was associated with higher values of GOH/10Percentile (p=0.03) and lower values of GOH/90Percentile (p=0.03). Loco-regional recurrence within 2 years was associated with higher values of GLCM3/4-7Correlation (p=0.04) and lower values of GLCM3/2-1InformationMeasureCorr1 (p=0.04). Results lost the statistical significance after correction for multiple testing. T stage was significantly correlated with 9 features, 4 of which (GLCM25/180-4InformationMeasureCorr2, Shape/MeanBreadth, GLCM25/90-1InverseDiffMomentNorm, and GLCM3/6-1InformationMeasureCorr1) retained statistical significance after False Discovery Rate correction. MRI-based radiomics is a feasible and promising approach for the prediction of tumor phenotype and local recurrence in OPSCC. Some radiomic features seem to be correlated with tumor characteristics and oncologic outcome however, larger collaborative studies are warranted in order to increase the statistical power and to obtain robust and validated results.


Assuntos
Carcinoma de Células Escamosas/diagnóstico por imagem , Imageamento por Ressonância Magnética , Recidiva Local de Neoplasia , Neoplasias Orofaríngeas/diagnóstico por imagem , Humanos , Recidiva Local de Neoplasia/diagnóstico por imagem , Prognóstico , Estudos Retrospectivos
6.
Ann Oncol ; 27(5): 812-8, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27052658

RESUMO

BACKGROUND: Several expression array studies identified molecular apocrine breast cancer (BC) as a subtype that expresses androgen receptor (AR) but not estrogen receptor α. We carried out a multicentre single-arm phase II trial in women with AR-positive, estrogen, progesterone receptor and HER2-negative (triple-negative) metastatic or inoperable locally advanced BC to assess the efficacy and safety of abiraterone acetate (AA) plus prednisone. PATIENTS AND METHODS: Patients with a metastatic or locally advanced, centrally reviewed, triple-negative and AR-positive (≥10% by immunohistochemistry, IHC) BC were eligible. Any number of previous lines of chemotherapy was allowed. AA (1000 mg) was administered once a day with prednisone (5 mg) twice a day until disease progression or intolerance. The primary end point was clinical benefit rate (CBR) at 6 months defined as the proportion of patients presenting a complete response (CR), partial response (PR) or stable disease (SD) ≥6 months. Secondary end points were objective response rate (ORR), progression-free survival (PFS) and safety. RESULTS: One hundred and forty-six patients from 27 centres consented for IHC central review. Of the 138 patients with sufficient tissue available, 53 (37.6%) were AR-positive and triple-negative, and 34 of them were included from July 2013 to December 2014. Thirty patients were eligible and evaluable for the primary end point. The 6-month CBR was 20.0% [95% confidence interval (CI) 7.7%-38.6%], including 1 CR and 5 SD ≥6 months, 5 of them still being under treatment at the time of analysis (6.4+, 9.2+, 14.5+, 17.6+, 23.4+ months). The ORR was 6.7% (95% CI 0.8%-22.1%). The median PFS was 2.8 months (95% CI 1.7%-5.4%). Fatigue, hypertension, hypokalaemia and nausea were the most common drug-related adverse events; the majority of them being grade 1 or 2. CONCLUSIONS: AA plus prednisone treatment is beneficial for some patients with molecular apocrine tumours and five patients are still on treatment. CLINICALTRIALSGOV: NCT01842321.


Assuntos
Acetato de Abiraterona/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Prednisona/administração & dosagem , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/classificação , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Receptor ErbB-2/genética , Receptores Androgênicos/genética , Receptores de Progesterona/genética , Resultado do Tratamento , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia
7.
Nature ; 434(7032): 462-9, 2005 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-15791247

RESUMO

A key challenge of functional genomics today is to generate well-annotated data sets that can be interpreted across different platforms and technologies. Large-scale functional genomics data often fail to connect to standard experimental approaches of gene characterization in individual laboratories. Furthermore, a lack of universal annotation standards for phenotypic data sets makes it difficult to compare different screening approaches. Here we address this problem in a screen designed to identify all genes required for the first two rounds of cell division in the Caenorhabditis elegans embryo. We used RNA-mediated interference to target 98% of all genes predicted in the C. elegans genome in combination with differential interference contrast time-lapse microscopy. Through systematic annotation of the resulting movies, we developed a phenotypic profiling system, which shows high correlation with cellular processes and biochemical pathways, thus enabling us to predict new functions for previously uncharacterized genes.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/embriologia , Caenorhabditis elegans/genética , Desenvolvimento Embrionário/genética , Genoma , Interferência de RNA , Animais , Caenorhabditis elegans/fisiologia , Biologia Computacional , Genes de Helmintos/genética , Genômica , Fenótipo , RNA de Helmintos/genética , RNA de Helmintos/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
8.
J Cell Sci ; 114(Pt 17): 3103-14, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11590237

RESUMO

The zeste-white 10 (zw10) and rough deal (rod) genes of Drosophila both encode kinetochore components, and mutations in either gene greatly increase the missegregation of sister chromatids during mitosis. Here, we present genetic, cytological and biochemical evidence for a close, evolutionarily conserved relationship between the ROD and ZW10 proteins. We show that the phenotypes caused by disruption of either gene's function are similar in Drosophila and in C. elegans. No additive effects are observed in zw10; rod double null mutants. In flies, the two proteins always colocalize and, moreover, require each other for their recruitment to the mitotic apparatus. The human ROD and ZW10 homologs also colocalize on HeLa cell kinetochores or kinetochore microtubules throughout most but not all of mitosis. Finally, we show that in both Drosophila and human cells, ROD and ZW10 are in fact physically associated, and in Drosophila these proteins are together constituents of a large (700-900 kDa), soluble macromolecular complex.


Assuntos
Proteínas de Ciclo Celular , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/fisiologia , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/fisiologia , Proteínas de Insetos/metabolismo , Proteínas de Insetos/fisiologia , Cinetocoros/metabolismo , Proteínas Associadas aos Microtúbulos , Fatores de Transcrição/metabolismo , Fatores de Transcrição/fisiologia , Animais , Caenorhabditis elegans , Cromátides/metabolismo , Cromossomos/metabolismo , Drosophila , Evolução Molecular , Técnica Indireta de Fluorescência para Anticorpo , Células HeLa , Humanos , Immunoblotting , Metáfase , Microscopia de Fluorescência , Mitose , Mutação , Fenótipo , Testes de Precipitina , Ligação Proteica , RNA Mensageiro/metabolismo , Técnicas do Sistema de Duplo-Híbrido
10.
Curr Biol ; 10(24): 1619-22, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11137018

RESUMO

As a step towards comprehensive functional analysis of genomes, systematic gene knockout projects have been initiated in several organisms [1]. In metazoans like C. elegans, however, maternal contribution can mask the effects of gene knockouts on embryogenesis. RNA interference (RNAi) provides an alternative rapid approach to obtain loss-of-function information that can also reveal embryonic roles for the genes targeted [2,3]. We have used RNAi to analyze a random set of ovarian transcripts and have identified 81 genes with essential roles in embryogenesis. Surprisingly, none of them maps on the X chromosome. Of these 81 genes, 68 showed defects before the eight-cell stage and could be grouped into ten phenotypic classes. To archive and distribute these data we have developed a database system directly linked to the C. elegans database (Wormbase). We conclude that screening cDNA libraries by RNAi is an efficient way of obtaining in vivo function for a large group of genes. Furthermore, this approach is directly applicable to other organisms sensitive to RNAi and whose genomes have not yet been sequenced.


Assuntos
Caenorhabditis elegans/genética , Expressão Gênica , Genes de Helmintos , RNA de Helmintos/antagonistas & inibidores , Animais , Caenorhabditis elegans/anatomia & histologia , Caenorhabditis elegans/embriologia , Caenorhabditis elegans/metabolismo , Bases de Dados Factuais , Feminino , Perfilação da Expressão Gênica , Biblioteca Gênica , Proteínas de Helminto/classificação , Proteínas de Helminto/genética , Morfogênese , Ovário/fisiologia , RNA de Helmintos/metabolismo
11.
Genetics ; 152(2): 605-16, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10353903

RESUMO

In Drosophila melanogaster and the endemic Hawaiian species D. grimshawi three Yolk protein (Yp) genes are expressed in a similar sex- and tissue-specific pattern. In contrast, DNA sequence comparisons of promoter/enhancer regions show low levels of similarity. We tested the functional significance of these observations by transforming D. melanogaster with the genomic region that includes the divergently transcribed D. grimshawi DgYp1 and DgYp2 genes; we found that the introduced genes were expressed in female fat body and in ovaries but not in males. Moreover, we found D. grimshawi proteins in the hemolymph and accumulating in ovaries. Using reporter constructs we showed that the intergenic region from D. grimshawi was sufficient to drive accurate expression, but some low level of ectopic expression was seen in males. Transforming D. melanogaster with constructs bearing deletions within the D. grimshawi intergenic region revealed only subtle effects in the overall level of expression, suggesting a high level of redundancy. Testing mutants in the sex-specific regulator doublesex revealed that it is capable of repressing the DgYp genes in males. Together, these data show that D. melanogaster trans-acting factors can regulate the in vivo pattern of DgYp expression and support the notion of a redundant and complex system of cis-acting elements.


Assuntos
Proteínas de Drosophila , Drosophila/genética , Proteínas do Ovo/genética , Animais , Sequência de Bases , Northern Blotting , DNA/genética , Proteínas de Ligação a DNA/fisiologia , Drosophila melanogaster/genética , Elementos Facilitadores Genéticos , Evolução Molecular , Feminino , Regulação da Expressão Gênica , Proteínas de Insetos/fisiologia , Masculino , Ovário/metabolismo , RNA/genética , RNA/metabolismo , Proteínas Recombinantes de Fusão/genética , Fatores Sexuais , Distribuição Tecidual
12.
Development ; 125(18): 3607-14, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9716526

RESUMO

Asymmetric cell divisions, critically important to specify cell types in the development of multicellular organisms, require polarized distribution of cytoplasmic components and the proper alignment of the mitotic apparatus. In Caenorhabditis elegans, the maternally expressed protein, PAR-3, is localized to one pole of asymmetrically dividing blastomeres and is required for these asymmetric divisions. In this paper, we report that an atypical protein kinase C (PKC-3) is essential for proper asymmetric cell divisions and co-localizes with PAR-3. Embryos depleted of PKC-3 by RNA interference die showing Par-like phenotypes including defects in early asymmetric divisions and mislocalized germline-specific granules (P granules). The defective phenotypes of PKC-3-depleted embryos are similar to those exhibited by mutants for par-3 and another par gene, par-6. Direct interaction of PKC-3 with PAR-3 is shown by in vitro binding analysis. This result is reinforced by the observation that PKC-3 and PAR-3 co-localize in vivo. Furthermore, PKC-3 and PAR-3 show mutual dependence on each other and on three of the other par genes for their localization. We conclude that PKC-3 plays an indispensable role in establishing embryonic polarity through interaction with PAR-3.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans/embriologia , Caenorhabditis elegans/enzimologia , Polaridade Celular/genética , Proteínas de Helminto/metabolismo , Proteína Quinase C/metabolismo , Animais , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/genética , Cálcio/metabolismo , DNA de Helmintos/química , Diglicerídeos/metabolismo , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/enzimologia , Ativação Enzimática , Regulação da Expressão Gênica no Desenvolvimento , Genes de Helmintos , Proteínas de Helminto/genética , Dados de Sequência Molecular , Oligonucleotídeos Antissenso/farmacologia , Fosfatidilserinas/metabolismo , Ligação Proteica , Proteína Quinase C/genética , Proteínas Serina-Treonina Quinases , RNA de Helmintos/farmacologia
13.
Mol Phylogenet Evol ; 7(2): 173-84, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9126558

RESUMO

The picture-winged species Drosophila grimshawi is unique among Hawaiian Drosophila in its wide geographic range, having populations on several islands of the Hawaiian archipelago. This distribution contrasts with the pattern of single-island endemism observed in most of the picture-winged group; significantly, it does not concur with predictions of the founder theory, where speciation is the typical outcome of founder events involving colonization of a new island. To examine this anomalous situation, we have taken a phylogenetic approach in an attempt to resolve the relationships among taxa and decipher the most probable colonization scenario. We have obtained both morphological and molecular data for all the D. grimshawi populations as well as the closely related species D. pullipes, and two outgroup species, using scanning electron microscopy to score ultrastructural features of the chorion or eggshell, and PCR amplification and nucleotide sequencing to acquire sequence data on Yp1, one of the three Yolk protein genes. In addition, we have used available data on Yolk Protein electrophoretic pattern and jousting, oviposition, and mating behavioral characters. Analyses of these data sets, either individually or in combination, indicate that there are two separate and ecologically distinct clades within this species complex. One clade includes the Kauai and Oahu populations of grimshawi, as well as the closely related species D. pullipes from Hawaii, all of which are classified as ecological specialists with respect to their oviposition and breeding substrate. The other clade includes all the ecologically generalist grimshawi populations of the Maui Nui island complex. The phylogenetic results do not concur with the previously proposed hypothesis that D. pullipes originated from a founder derived from the Maui Nui complex and further suggest that these taxa are in need of taxonomic revision.


Assuntos
Drosophila/genética , Filogenia , Animais , Sequência de Bases , Córion/ultraestrutura , Primers do DNA/genética , Drosophila/classificação , Drosophila/ultraestrutura , Evolução Molecular , Feminino , Genes de Insetos , Genética Populacional , Havaí , Microscopia Eletrônica de Varredura , Dados de Sequência Molecular , Óvulo/ultraestrutura , Especificidade da Espécie
14.
J Mol Evol ; 43(2): 116-24, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8660436

RESUMO

Nucleotide sequence analysis has demonstrated that interspecific size variation in the YP2 yolk protein among Hawaiian Drosophila is due to in-frame insertions and deletions in two repetitive segments of the coding region of the Yp2 gene. Sequence comparisons of the complex repetitive region close to the 5' end of this gene across 34 endemic Hawaiian taxa revealed five length morphs, spanning a length difference of 21 nucleotides (nt). A phylogenetic character reconstruction of the length mutations on an independently derived molecular phylogeny showed clade-specific length variants arising from six ancient events: two identical insertions of 6 nt, and four deletions, one of 6 nt, one of 12 nt, and two identical but independent deletions of 15 nt. These mutations can be attributed to replication slippage with nontandem trinucleotide repeats playing a major role in the slipped-strand mispairing. Geographic analysis suggests that the 15 nt deletion which distinguishes the planitibia subgroup from the cyrtoloma subgroup occurred on Oahu about 3 million years ago. The homoplasies observed caution against relying too heavily on nucleotide insertions/deletions for phylogenetic inference. In contrast to the extensive repeat polymorphisms within other Drosophila and the human species, the more complex 5' Yp2 repetitive region analyzed here appears to lack polymorphism among Hawaiian Drosophila, perhaps due to founder effects, low population sizes, and hitchhiking effects of selection on the immediately adjacent 5' region.


Assuntos
DNA/genética , Proteínas de Drosophila , Drosophila/genética , Proteínas do Ovo/genética , Mutação , Filogenia , Polimorfismo Genético , Sequências Repetitivas de Ácido Nucleico , Vitelogeninas , Sequência de Aminoácidos , Animais , Sequência de Bases , Primers do DNA , Elementos de DNA Transponíveis , Variação Genética , Havaí , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Deleção de Sequência , Homologia de Sequência do Ácido Nucleico
15.
Curr Biol ; 5(10): 1129-39, 1995 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-8548285

RESUMO

BACKGROUND: The endemic Hawaiian drosophilids, a unique group that are remarkable for their diversity and rapid proliferation, provide a model for analysis of the process of insular speciation. Founder events and accompanying random drift, together with shifts in sexual selection, appear to explain the dramatic divergence in male morphology and mating behaviour among these flies, but these forces do not account for their spectacular ecological diversification into a wide array of breeding niches. Although recognized as contributing to the success of this group, the precise role of adaptive shifts has not been well defined. RESULTS: To delineate the pattern of ecological diversification in the evolution of Hawaiian Drosophila, we generated a molecular phylogeny, using nucleotide sequences from the yolk protein gene Yp1, of 42 endemic Hawaiian and 5 continental species. By mapping ecological characters onto this phylogeny, we demonstrate that monophagy is the primitive condition, and that decaying leaves were the initial substrate for oviposition and larval development. Shifts to decaying stems, bark and tree fluxes followed in more derived species. By plotting female reproductive strategies, as reflected in ovarian developmental type, on the molecular tree, we also demonstrate a phylogenetic trend toward increasing fecundity. We find some statistical support for correlations between ecological shifts and shifts in female reproductive strategies. CONCLUSIONS: Because of the short branches at the base of the phylogram, which lead to ecologically diverse lineages, we conclude that much of the adaptive radiation into alternate breeding substrates occurred rapidly, early in the group's evolution in Hawaii. Furthermore, we conclude that this ecological divergence and the correlated changes in ovarian patterns that adapt species to their ecological habitats were contributing factors in the major phyletic branching within the Hawaiian drosophilid fauna.


Assuntos
Drosophila/classificação , Filogenia , Adaptação Fisiológica , Animais , Sequência de Bases , Primers do DNA , Drosophila/genética , Ecologia , Proteínas do Ovo/genética , Feminino , Havaí , Masculino , Dados de Sequência Molecular , Reprodução
16.
Artigo em Francês | MEDLINE | ID: mdl-6853972

RESUMO

58 sterile women who had perfect biphasic temperature curves through their menstrual cycles were examined by laparoscopy in the luteal phase of the cycle. No pelvic lesion was found. In 21 patients it was seen that the follicle had not ruptured (the so-called non-ruptured follicle syndrome). In a further 9 cases there was no luteal follicle to be seen on the surface of the ovary. The respective values of the plasma biochemical parameters which reflect ovarian secretion in the luteal phase are discussed; the importance of oestrogen secretion at the 6th day of the luteal phase is emphasized. It has been shown that there are significant statistical differences in the levels of oestradiol in the blood.


Assuntos
Corpo Lúteo/fisiopatologia , Estradiol/sangue , Infertilidade Feminina/fisiopatologia , Progesterona/sangue , Endoscopia , Feminino , Humanos , Fase Luteal
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