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1.
J Evol Biol ; 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38699972

RESUMO

Molluscs have undergone many transitions between separate sexes and hermaphroditism, which is of interest for studying the evolution of sex determination and differentiation. Here we combined multi-locus genotypes obtained from RAD sequencing with anatomical observations of the gonads for three deep-sea hydrothermal vent gastropods of the genus Alviniconcha living in the southwest Pacific. We found that all three species (A. boucheti, A. strummeri, and A. kojimai) share the same male-heterogametic XY sex determination system, but that the gonads of XX A. kojimai individuals are invaded by a variable proportion of male reproductive tissue. The identification of Y-specific RAD loci (found only in A. boucheti) and the phylogenetic analysis of three sex-linked loci shared by all species suggested that X-Y recombination has evolved differently within each species. This situation of three species showing variation in gonadal development around a common sex determination system provides new insights into the reproductive mode of poorly known deep-sea species and opens up an opportunity to study the evolution of recombination suppression on sex chromosomes and its association with mixed or transitory sexual systems.

2.
J Appl Stat ; 49(3): 764-781, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35706767

RESUMO

We propose a new methodology for selecting and ranking covariates associated with a variable of interest in a context of high-dimensional data under dependence but few observations. The methodology successively intertwines the clustering of covariates, decorrelation of covariates using Factor Latent Analysis, selection using aggregation of adapted methods and finally ranking. A simulation study shows the interest of the decorrelation inside the different clusters of covariates. We first apply our method to transcriptomic data of 37 patients with advanced non-small-cell lung cancer who have received chemotherapy, to select the transcriptomic covariates that explain the survival outcome of the treatment. Secondly, we apply our method to 79 breast tumor samples to define patient profiles for a new metastatic biomarker and associated gene network in order to personalize the treatments.

3.
Aquat Toxicol ; 155: 52-61, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24992287

RESUMO

In order to provide reliable information about responsiveness of biomarkers during environmental monitoring, there is a need to improve the understanding of inter-population differences. The present study focused on eight populations of zebra mussels and aimed to describe how variable are biomarkers in different sampling locations. Biomarkers were investigated and summarised through the Integrated Biomarker Response (IBR index). Inter-site differences in IBR index were analysed through comparisons with morphological data, proteomic profiles and genetic background of the studied populations. We found that the IBR index was a good tool to inform about the status of sites. It revealed higher stress in more polluted sites than in cleaner ones. It was neither correlated to proteomic profiles nor to genetic background, suggesting a stronger influence of environment than genes. Meanwhile, morphological traits were related to both environment and genetic background influence. Together these results attest the benefit of using biological tools to better illustrate the status of a population and highlight the need of consider inter-population difference in their baselines.


Assuntos
Dreissena/metabolismo , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores , Demografia , França , Proteômica , Rios , Poluentes Químicos da Água/análise
4.
Mol Ecol ; 18(18): 3903-17, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19709370

RESUMO

The use of sequence polymorphism from individual mitochondrial genes to infer past demography has recently proved controversial because of the recurrence of selective sweeps acting over genes and the need for unlinked multilocus data sets. However, comparative analyses using several species for one gene and/or multiple genes for one species can serve as a test for potential selective effects and clarify our understanding of historical demographic effects. This study compares nucleotide polymorphisms in mitochondrial cytochrome oxidase I across seven deep-sea hydrothermal vent species that live along the volcanically active East Pacific Rise. Approximate Bayesian Computation (ABC) method, developed to trace shared vicariant events across species pairs, indicates the occurrence of two across species divergence times, and suggests that the present geographical patterns of genetic differentiation may be explained by two periods of significant population isolation. The oldest period dates back 11.6 Ma and is associated with the vent limpet Lepetodrilus elevatus, while the most recent period of isolation is 1.3 Ma, which apparently affected all species examined and coincides with a transition zone across the equator. Moreover, significant negative Tajima's D and star-like networks were observed for all southern lineages, suggesting that these lineages experienced a concomitant demographic and geographical expansion about 100 000-300 000 generations ago. This expansion may have initiated from a wave of range expansions during the secondary colonization of new sites along the Southern East Pacific Rise (founder effects below the equator) or recurrent bottleneck events because of the increase of eruptive phases associated with the higher spreading rates of the ridge in this region.


Assuntos
Evolução Molecular , Gastrópodes/genética , Especiação Genética , Filogenia , Poliquetos/genética , Animais , Teorema de Bayes , DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Gastrópodes/classificação , Genética Populacional , Geografia , Haplótipos , Oceano Pacífico , Poliquetos/classificação , Análise de Sequência de DNA , Especificidade da Espécie
5.
Ann Dermatol Venereol ; 132(12 Pt 1): 970-4, 2005 Dec.
Artigo em Francês | MEDLINE | ID: mdl-16446639

RESUMO

BACKGROUND: Several studies have shown a high prevalence of rash induced by nevirapine. However, there is little knowledge about the risk factors associated with nevirapine-induced rash. The aim of this study was to identify risk factors associated with the occurrence of rash during the treatment with nevirapine of HIV-infected patients. METHODS: A retrospective study was conducted in the dermatology department of Besançon university teaching hospital between November 1998 and September 2001. The study included all HIV-infected patients receiving HAART regimens that included nevirapine. The following data were collected: age, sex, CDC classification of HIV, CD4 and CD8 lymphocyte counts, plasma HIV RNA load, hepatitis B, C and cytomegalovirus serostatus, history of drug allergy, concomitant medication (other antiretroviral drugs, corticosteroids, antihistamines). Univariate analysis was performed using a Chi2 test or Fischer's test and Student's t test. Fischer's test and the Cox proportional hazards model were used in the multivariate analysis. RESULTS: During the study period, 101 HIV-infected patients (74 men and 27 women; mean age: 41.6 +/- 10.3 years) were treated with HAART regimens including nevirapine. Fourteen developed cutaneous drug-reactions attributable to nevirapine (13.86%). We observed 13 cases of maculopapular exanthema and 1 case of DRESS. In the univariate analysis, female gender (p=0.002), plasma HIV RNA load > 10,000 copies/ml (p=0.05), heterosexual transmission (p=0.002) and abacavir treatment (p=0.05) constituted risk factors associated with rash. In the multivariate analysis, only female gender (p<0.0001) and plasma HIV RNA load > 10,000 copies/ml (p=0.0007) were associated with rash. DISCUSSION: The results of this study confirm the high frequency of toxidermy associated with nevirapine therapy. The risk factors associated with occurrence of rash due to nevirapine therapy were female gender and plasma RNA > 10,000 copies/ml. Several studies showed absence of any protective effect of antihistamines and corticosteroids in preventing the cutaneous adverse reactions associated with nevirapine. The identification of risk factors closely associated with nevirapine-induced rash could help physicians determine new strategies for safer use of nevirapine in the HAART regimen.


Assuntos
Toxidermias/etiologia , Infecções por HIV/tratamento farmacológico , Nevirapina/efeitos adversos , Inibidores da Transcriptase Reversa/efeitos adversos , Adulto , Terapia Antirretroviral de Alta Atividade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nevirapina/uso terapêutico , RNA Viral/análise , Estudos Retrospectivos , Inibidores da Transcriptase Reversa/uso terapêutico , Fatores de Risco , Fatores Sexuais , Carga Viral
6.
Ann Dermatol Venereol ; 131(11): 947-51, 2004 Nov.
Artigo em Francês | MEDLINE | ID: mdl-15602380

RESUMO

INTRODUCTION: High risk human papillomaviruses (HPV) have emerged as risk factors for anal carcinoma particularly in HIV-infected patients who demonstrate a high rate of anal HPV infection. Considering the relationship between the presence of anal infection and the development of neoplastic lesions, we wished to assess the capacity of imiquimod to eradicate latent HPV infection in HIV-infected patients. PATIENTS AND METHODS: We conducted a prospective, randomized, double-blind and vehicle controlled study. Two consecutive anal swabs were taken at 2 month intervals and only patients with two consecutive tests positive for the detection of HPV-DNA (Hybrid Capture II) were included. Patients with persistent latent HPV infection were divided into 2 groups who applied imiquimod versus vehicle during 6 weeks. HPV-DNA presence was then investigated 2 and 4 months following the onset of treatment. RESULTS: Among the 80 HIV-infected patients, 26 (32.5 p. 100) had 2 positive consecutive assays, and 19 patients were included in the study. After randomization, 9 patients received imiquimod and 10 vehicle. There was no significant difference between treatment groups according to the following criteria: gender, route of HIV transmission, CDC stage, prior medical history of sexually transmitted diseases or anogenital warts. 33.3 p. 100 (3/9) of patients treated with imiquimod were negative at M2, whereas 100 p. 100 (10/10) vehicle treated-patients remained positive (p=0.08). Similar results were observed at the M4 visit. DISCUSSION: Our study confirmed the increased prevalence of latent HPV-DNA infection in HIV-infected patients. In spite of the low number of treated patients, we did not observe a statistically significant decrease in HPV-DNA in anal swabs from imiquimod-treated patients as compared to placebo-treated patients.


Assuntos
Adjuvantes Imunológicos/farmacologia , Aminoquinolinas/farmacologia , Infecções por HIV/complicações , Infecções por Papillomavirus/tratamento farmacológico , Adjuvantes Imunológicos/uso terapêutico , Adolescente , Adulto , Idoso , Aminoquinolinas/uso terapêutico , Doenças do Ânus/tratamento farmacológico , Doenças do Ânus/virologia , Neoplasias do Ânus/prevenção & controle , Neoplasias do Ânus/virologia , Carcinoma/prevenção & controle , Carcinoma/virologia , Método Duplo-Cego , Feminino , Humanos , Imiquimode , Masculino , Pessoa de Meia-Idade , Infecções por Papillomavirus/etiologia , Estudos Prospectivos , Fatores de Risco
7.
J Radiol ; 85(10 Pt 1): 1726-8, 2004 Oct.
Artigo em Francês | MEDLINE | ID: mdl-15669567

RESUMO

The authors report a case of unilateral primary adrenal lymphoma presenting with abdominal and dorsal pain. Primary lymphoma of the genitourinary tract, specifically adrenal localisation, is a rare disease. CT is the current best imaging modality for evaluating retroperitoneal masses and improving detection, characterization as well as assessing extension. Diagnosis is based on histology.


Assuntos
Neoplasias das Glândulas Suprarrenais/diagnóstico , Linfoma Difuso de Grandes Células B/diagnóstico , Idoso , Humanos , Masculino , Tomografia Computadorizada por Raios X
9.
Clin Exp Metastasis ; 18(2): 171-8, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11235993

RESUMO

Several matrix metalloproteinases (MMPs) and tissue inhibitors of MMPs (TIMPs) were studied in highly invasive (MDA-MB-231) and slightly invasive (MCF-7, T47D, BT-20) breast cancer cell lines. Investigations were carried out at the protein level and/or at the mRNA level, either in cells cultured as monolayers on plastic, or in cells seeded on a thin layer of Matrigel basement membrane matrix. Analysis of MMP expression by RT-PCR showed expression of MMP-1. MMP-3, and MMP-13 in highly invasive MDA-MB-231 cells, but not in slightly invasive cell lines. The extracellular secretion of MMP-1 and MMP-3 by MDA-MB 231 cells could be also shown by ELISA. TIMP-1 and TIMP-2 mRNAs were found in all cell lines, however, the extracellular secretion of both TIMPs was much higher in MDA-MB-231 cells than in the other cell lines. When the cells were cultured on Matrigel matrix, MMP-9 expression was induced in MDA-MB-231 cells only, as assessed by RT-PCR and zymography experiments. The invasive potential of MDA-MB-231 cells evaluated in vitro through Matrigel was significantly inhibited by the MMP inhibitor BB-2516, by 25% and 50% at the concentrations of 2 x 10(-6) M and 10(-5) M, respectively. In conclusion, our data show that highly invasive MDA-MB-231 cells but not slightly invasive T47D, MCF-7 and BT-20 cells express MMP-1, MMP-3, MMP-9 and MMP-13. MMP-9 which is specifically up-regulated by cell contact to Matrigel, may play a key role in the invasiveness of MDA-MB-231 cells through basement membranes.


Assuntos
Neoplasias da Mama/enzimologia , Metaloproteinases da Matriz/metabolismo , Invasividade Neoplásica , Sequência de Bases , Membrana Basal/enzimologia , Neoplasias da Mama/patologia , Colágeno , Primers do DNA , Combinação de Medicamentos , Ensaio de Imunoadsorção Enzimática , Ácidos Hidroxâmicos/farmacologia , Laminina , Inibidores de Metaloproteinases de Matriz , Proteoglicanas , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Inibidores Teciduais de Metaloproteinases/metabolismo , Células Tumorais Cultivadas
10.
J Radiol ; 78(3): 223-5, 1997 Mar.
Artigo em Francês | MEDLINE | ID: mdl-9113150

RESUMO

Ovarian vein syndrome is classically described on the right side. Patients present with lumbar pain or renal colics due to a compression of the ureter between the external iliac artery and a dilated ovarian vein. We report an unusual case of left ovarian vein syndrome between a dilated ovarian vein and the psoas muscle, with a similar clinical presentation.


Assuntos
Ovário/irrigação sanguínea , Dilatação Patológica , Feminino , Humanos , Região Lombossacral , Pessoa de Meia-Idade , Dor/etiologia , Síndrome , Ureter/patologia , Veias/patologia
12.
J Radiol ; 77(3): 205-8, 1996 Mar.
Artigo em Francês | MEDLINE | ID: mdl-8830146

RESUMO

Adenomyomatosis of the gall bladder is a classical but seldom recognized cause of gallbladder wall thickening. The authors review the imaging features of this disease and emphasize the value of ultrasound and MRI. Although considered a benign disease, some recently described cases of neoplastic transformation may warrant surgery.


Assuntos
Adenomioma/diagnóstico por imagem , Imageamento por Ressonância Magnética , Neoplasias da Bexiga Urinária/diagnóstico por imagem , Adenomioma/diagnóstico , Adenomioma/cirurgia , Adulto , Feminino , Vesícula Biliar/patologia , Humanos , Ultrassonografia , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/cirurgia
15.
Ann Clin Biochem ; 32 ( Pt 6): 545-9, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8579286

RESUMO

A 34-year-old man with pulmonary emphysema was found to have a mild alpha 1 proteinase inhibitor (alpha 1 PI) deficiency. alpha 1 PI status was investigated in this patient and in 35 members of his family. The alpha 1 PI investigations included alpha 1 PI concentration and phenotype and serum inhibitory capacity for trypsin and pancreatic elastase. Fifteen members of the family had alpha 1 PI concentration and inhibitory capacities below the lower normal limit. Five of these members were characterized by the heterozygous MP phenotype and the 10 others by an apparently homozygous M phenotype, in which the M allele may be associated with another unidentified deficiency allele. Two members of the family had alpha 1 PI concentration and elastase inhibitory capacity below the lower normal limits and trypsin inhibitory capacity within the normal range. They were both characterized by the MP phenotype. Six of these 17 members (three of PI type M and three of PI type MP) showed chronic pulmonary symptoms, whereas among the 19 alpha 1 PI non deficient members, no member had a history of significant pulmonary symptoms.


Assuntos
Doenças Respiratórias/genética , Deficiência de alfa 1-Antitripsina , Adulto , Alelos , Enfisema/sangue , Heterozigoto , Homozigoto , Humanos , Masculino , Linhagem , Fenótipo , Doenças Respiratórias/sangue , Fumar , alfa 1-Antitripsina/genética , alfa 1-Antitripsina/metabolismo
17.
Clin Chem ; 38(9): 1694-7, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1526000

RESUMO

Synovial fluid samples were collected from 45 patients with rheumatoid arthritis, spondylarthropathy, or osteoarthritis, to study their content of elastase (EC 3.4.21.37) and of cysteine proteinases (EC 3.4.22.1, 3.4.22.15). We measured both elastase complexed with alpha 1-proteinase inhibitor and elastase activity toward the substrate L-pyroglutamyl-L-prolyl-L-valine-p-nitroanilide. Cysteine proteinase activities were measured with the substrates N-benzyloxycarbonyl-L-phenylalanyl-L-arginine-7-amido-4-methylcoumarin (Z-Phe-Arg-AMC) and Z-Arg-Arg-AMC and the inhibitor E-64 [L-trans-epoxysuccinyl-leucyl-amido-(4-guanidino)-butane]. In all these enzyme assays, higher median values were obtained in inflammatory arthropathies than in osteoarthritis. The concentration of the elastase-alpha 1-proteinase inhibitor complex and of elastase and cysteine proteinase activities were statistically higher in patients with rheumatoid arthritis than in patients with osteoarthritis. The difference in results between patients with spondylarthropathy and patients with osteoarthritis was statistically significant only for the elastase-alpha 1-proteinase inhibitor complex. The median values of the complex and of both enzyme activities were higher in patients with rheumatoid arthritis than in patients with spondylarthropathy; however, the difference was statistically significant only for the cysteine proteinase activity measured with Z-Arg-Arg-AMC substrate. These results suggest that both elastase and cysteine proteinases, which are increased in patients with inflammatory arthritis, are involved in cartilage degradation in these arthropathies.


Assuntos
Artrite Reumatoide/enzimologia , Cisteína Endopeptidases/metabolismo , Osteoartrite/enzimologia , Elastase Pancreática/metabolismo , Doenças da Coluna Vertebral/enzimologia , Líquido Sinovial/enzimologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Aminoácidos , Cumarínicos/metabolismo , Inibidores de Cisteína Proteinase/metabolismo , Dipeptídeos/metabolismo , Feminino , Humanos , Leucina/análogos & derivados , Leucina/metabolismo , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Especificidade por Substrato
18.
Arch Int Physiol Biochim ; 86(3): 601-12, 1978 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-83827

RESUMO

Dog enterocyte brush border proteins have been studied after a 75% proximal resection of the small bowel. This study was carried on microvillar membrane preparations purified from ileal mucosa sampled before and after regeneration on neighbouring intestinal segments, each animal acting as its own control. After six weeks of regeneration a statistically significant decrease of the following enzyme specific activities was observed: lactase, cellobiase, maltase, sucrase, palatinase, dextranase, trehalase, alkaline phosphatase, aminopeptidase and gamma-glutamyl transferase. Analysis of brush border proteins by polyacrylamide gel electrophoresis in presence of sodium dodecyl sulphate have shown after regeneration a decreased rate for the proteins with a molecular weight higher than 100,000 daltons. Modifications of electrophoretic patterns seem to be related to the specific activity decreases observed for brush border enzymes after regeneration, since the molecular weight of these enzymes were found between 116,000 and 285,000 daltons, after gel filtration.


Assuntos
Membrana Celular/metabolismo , Intestino Delgado/cirurgia , Proteínas de Membrana/metabolismo , Microvilosidades/metabolismo , Animais , Cães , Hidrolases/metabolismo , Intestino Delgado/fisiologia , Masculino , Peso Molecular
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