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1.
Animals (Basel) ; 8(10)2018 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-30322178

RESUMO

Long-range vocal communication in socially monogamous titi monkeys is mediated by the production of loud, advertising calls in the form of solos, duets, and choruses. We conducted a power spectral analysis of duets and choruses (simply "duets" hereafter) followed by linear discriminant analysis using three acoustic parameters-dominant frequency of the combined signal, duet sequence duration, and pant call rate-comparing the coordinated vocalizations recorded from 36 family groups at 18 sites in Bolivia, Peru and Ecuador. Our analysis identified four distinct duetting patterns: (1) a donacophilus pattern, sensu largo, characteristic of P. donacophilus, P. pallescens, P. olallae, and P. modestus; (2) a moloch pattern comprising P. discolor, P. toppini, P. aureipalatii, and P. urubambensis; (3) a torquatus pattern exemplified by the duet of Cheracebus lucifer; and (4) the distinctive duet of P. oenanthe, a putative member of the donacophilus group, which is characterized by a mix of broadband and narrowband syllables, many of which are unique to this species. We also document a sex-related difference in the bellow-pant phrase combination among the three taxa sampled from the moloch lineage. Our data reveal a presumptive taxonomic incoherence illustrated by the distinctive loud calls of both P. urubambensis and P. oenanthe within the donacophilus lineage, sensu largo. The results are discussed in light of recent reassessments of the callicebine phylogeny, based on a suite of genetic studies, and the potential contribution of environmental influences, including habitat acoustics and social learning. A better knowledge of callicebine loud calls may also impact the conservation of critically endangered populations, such as the vocally distinctive Peruvian endemic, the San Martin titi, P. oenanthe.

2.
Vox Sang ; 109(2): 173-80, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25854538

RESUMO

BACKGROUND: Transfusion-induced alloimmunization has severe clinical consequences including haemolytic transfusion reactions, impaired transfused RBCs longevity and greater difficulty in finding compatible blood. Molecular analysis of genomic DNA now permits prediction of blood group phenotypes based on identification of single nucleotide polymorphisms. Implementation of molecular technologies in donor centres would be helpful in finding RBC units for special patient populations, but DNA extraction remains an obstacle to donor genotyping. MATERIALS AND METHODS: We propose a simple method compatible with high throughput that allows blood group genotyping using a multiplex commercial kit without the need for DNA extraction. The principle relies on pre-PCR treatment of whole blood using heating/cooling procedure in association with a recombinant hotstart polymerase. RESULTS: In a prospective analysis, we yielded 5628 alleles identification and designated 63 donors with rare blood, that is either negative for a high-frequency antigen or with a rare combination of common antigens. CONCLUSION: The procedure was optimized for simplicity of use in genotyping platform and would allow not only to supply antigen-matched products to recipients but also to find rare phenotypes. This methodology could also be useful for establishing a donor repository for human platelet antigens (HPA)-matched platelets since the same issues are involved for patients with neonatal alloimmune thrombocytopenia or post-transfusion purpura.


Assuntos
Doadores de Sangue , Técnicas de Genotipagem/métodos , Polimorfismo de Nucleotídeo Único , Feminino , Humanos , Masculino , Reação em Cadeia da Polimerase/métodos
3.
Folia Primatol (Basel) ; 86(6): 525-33, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26824671

RESUMO

We calculated the population density of the critically endangered Callicebus oenanthe in the Ojos de Agua Conservation Concession, a dry forest area in the department of San Martin, Peru. Results showed significant differences (p < 0.01) in group densities between forest boundaries (16.5 groups/km2, IQR = 21.1-11.0) and forest interior (4.0 groups/km2, IQR = 5.0-0.0), suggesting the 2,550-ha area harbours roughly 1,150 titi monkeys. This makes Ojos de Agua an important cornerstone in the conservation of the species, because it is one of the largest protected areas where the species occurs.


Assuntos
Ecologia/métodos , Pitheciidae/fisiologia , Vocalização Animal , Animais , Peru , Densidade Demográfica
4.
Transfus Clin Biol ; 21(6): 289-95, 2014 Dec.
Artigo em Francês | MEDLINE | ID: mdl-25443328

RESUMO

AIM OF THE STUDY: Current knowledge of the molecular basis of most blood groups enables genetic testing for blood groups to overcome the limitations of agglutination. A retrospective review was carried out on genotyping assays performed between 2011 and 2013. METHODS AND PATIENTS: The Molecular Hematology Laboratory of the EFS Alpes-Méditerranée implements commercially available tools (BioArray, Gen-Probe) and other techniques (TaqMan, tetra-primer ARMS-PCR, sequencing). It provides a high-level of expertise in molecular biology, complying with regulatory requirements and standards. RESULTS: A total of 2382 genotyping assays was performed including 764 extended typings and 115 large extended typings essentially in cases involving multiple transfusion and suspected rare blood type. Phenotype discrepancies linked to the RH system accounted for 1501 genotypings. Discrepancies linked to the D and E were mainly related to an allele coding for weak antigen (weak D type 1, 2, 3 and EIV) while those linked to C, c and e antigens were related to an allele coding for a partial antigen (RN, ces(340), ceMo). A high prevalence of (C)ces haplotype in trans of a DAR allele was observed in Afro-Caribbean (54/62). CONCLUSION: In transfusion medicine, red-cell genotyping can overcome the limitations of hemagglutination. It must be used only in situations where it provides a benefit either for the patient or resource management. For implementation of appropriate transfusional practices, this technique requires a sound knowledge of the genetic characteristics of blood groups and clinically relevant variants. It also requires competency with molecular biology tools and continuously updated scientific data.


Assuntos
Antígenos de Grupos Sanguíneos/genética , Tipagem e Reações Cruzadas Sanguíneas , Transfusão de Eritrócitos , Técnicas de Genotipagem , Alelos , DNA/genética , França , Frequência do Gene , Genótipo , Técnicas de Genotipagem/estatística & dados numéricos , Humanos , Fenótipo , Estudos Retrospectivos , Sistema do Grupo Sanguíneo Rh-Hr/genética , Reação Transfusional/prevenção & controle
5.
Vox Sang ; 103(4): 352-5, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22686562

RESUMO

The D- - phenotype is a genetic variant of the Rh blood group system. It expresses D antigen but lacks C, c, E and e antigens. In D- - phenotype, the RHCE coding region is extensively modified by RHD sequence replacement, nucleotide deletion or splice-site changes. This article reports the identification of a new D- - haplotype in a Comorian man. It exhibits a hybrid gene in which RHCE gene exons 3-8 have been replaced by RHD sequences on the RHCE * C allele background. This allele is associated with no expression of c/C and e/E antigens and overexpression of RhD antigen.


Assuntos
Sistema do Grupo Sanguíneo Rh-Hr/genética , Antígenos de Grupos Sanguíneos/genética , Antígenos de Grupos Sanguíneos/imunologia , Comores , Epitopos/genética , Epitopos/imunologia , Haplótipos , Humanos , Masculino , Fenótipo , Sistema do Grupo Sanguíneo Rh-Hr/imunologia
6.
Transfus Med ; 22(3): 192-8, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22420413

RESUMO

BACKGROUND: Most studies of the molecular basis of Rhesus D-negative phenotype have been conducted in Caucasian and African populations. A comprehensive survey of RHD alleles was lacking in people from North Africa (Tunisians, Moroccans and Algerians) which could be very efficient for managing donors and patients carrying an RHD molecular variant. We analyse the molecular background of D-negative population in Tunisia in the present study. MATERIALS AND METHODS: Blood samples were collected from native Tunisians. A total of 448 D-negative donors from different regions of Tunisia were analysed by RHD genotyping according to an adopted strategy using real-time PCR, ASP-PCR and sequencing. RESULTS: Among the 448 D-negative samples, 443 were phenotyped unequivocally as true D-negative including three molecular backgrounds which were RHD gene deletion (n = 437), RHDψ pseudogene (n = 2) and RHD-CE-D hybrid gene (n = 4) with the respective frequencies of 0·9900, 0·0023 and 0·0046. The remaining five samples, in discordance with the serological results, were identified as two weak D type 11, one weak D type 29, one weak D type 4·0 and one DBT-1 partial D. CONCLUSION: This study showed that the Tunisian population gets closer to Caucasians, given that the RHD gene deletion is the most prevalent cause of D-negative phenotype, but it is slightly different by the presence of the RHDψ pseudogene which was found with a very low frequency compared with that described in the African population. Nevertheless, the relative occurrence of weak D variants among studied serologically D-negative samples make necessary the adaptation of RHD genotyping strategy to the spectrum of prevalent alleles.


Assuntos
Sistema do Grupo Sanguíneo Rh-Hr/genética , Alelos , Tipagem e Reações Cruzadas Sanguíneas , DNA/genética , Éxons/genética , Deleção de Genes , Regulação da Expressão Gênica/genética , Frequência do Gene , Genótipo , Haplótipos/genética , Humanos , Fenótipo , Pseudogenes , Reação em Cadeia da Polimerase em Tempo Real , Sistema do Grupo Sanguíneo Rh-Hr/biossíntese , Tunísia
7.
Arch Pediatr ; 15(9): 1433-6, 2008 Sep.
Artigo em Francês | MEDLINE | ID: mdl-18676128

RESUMO

In children, pseudohypoparathyroidism (PHP) is a rare but classical cause of basal ganglia calcifications. It is caused by resistance to parathormone (PTH). Hypocalcemia, which may be symptomatic, is its main feature. We report the case of a 13-year-old boy, affected by type Ib PHP revealed by hypocalcemia and seizures, with basal ganglia calcifications on the CT scan. We describe the characteristics of the 2 main types of PHP and emphasize the search for this disease when basal ganglia calcifications are discovered, even fortuitously, on a cerebral CT scan.


Assuntos
Doenças dos Gânglios da Base/etiologia , Calcinose/etiologia , Pseudo-Hipoparatireoidismo/diagnóstico , Adolescente , Doenças dos Gânglios da Base/diagnóstico por imagem , Calcinose/diagnóstico por imagem , Humanos , Hipocalcemia/etiologia , Masculino , Radiografia , Convulsões/etiologia
8.
Leukemia ; 21(7): 1481-7, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17476280

RESUMO

Monitoring of BCR-ABL transcripts has become established practice in the management of chronic myeloid leukemia. However, nucleic acid amplification techniques are prone to variations which limit the reliability of real-time quantitative PCR (RQ-PCR) for clinical decision making, highlighting the need for standardization of assays and reporting of minimal residual disease (MRD) data. We evaluated a lyophilized preparation of a leukemic cell line (K562) as a potential quality control reagent. This was found to be relatively stable, yielding comparable respective levels of ABL, GUS and BCR-ABL transcripts as determined by RQ-PCR before and after accelerated degradation experiments as well as following 5 years storage at -20 degrees C. Vials of freeze-dried cells were sent at ambient temperature to 22 laboratories on four continents, with RQ-PCR analyses detecting BCR-ABL transcripts at levels comparable to those observed in primary patient samples. Our results suggest that freeze-dried cells can be used as quality control reagents with a range of analytical instrumentations and could enable the development of urgently needed international standards simulating clinically relevant levels of MRD.


Assuntos
Perfilação da Expressão Gênica/métodos , Perfilação da Expressão Gênica/normas , Reação em Cadeia da Polimerase/métodos , Proteínas Tirosina Quinases/genética , RNA Mensageiro/análise , Liofilização , Proteínas de Fusão bcr-abl , Humanos , Indicadores e Reagentes , Células K562 , Reação em Cadeia da Polimerase/normas , Proteínas Tirosina Quinases/análise , Controle de Qualidade , Padrões de Referência
9.
Leuk Res ; 31(9): 1175-83, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17070575

RESUMO

This study has investigated quantification of chimerism in sex-mismatched transplantations by quantitative real time PCR (RQ-PCR) using FTA paper for blood sampling. First, we demonstrate that the quantification of DNA from EDTA-blood which has been deposit on FTA card is accurate and reproducible. Secondly, we show that fraction of recipient cells detected by RQ-PCR was concordant between the FTA and salting-out method, reference DNA extraction method. Furthermore, the sensitivity of detection of recipient cells is relatively similar with the two methods. Our results show that this innovative method can be used for MC assessment by RQ-PCR.


Assuntos
Quimerismo , DNA/sangue , Globinas/genética , Reação em Cadeia da Polimerase , Manejo de Espécimes , Feminino , Dosagem de Genes , Hematócrito , Transplante de Células-Tronco Hematopoéticas , Humanos , Contagem de Leucócitos , Masculino , Papel , Contagem de Plaquetas , Kit de Reagentes para Diagnóstico , Sensibilidade e Especificidade , Manejo de Espécimes/métodos
10.
Endocr Relat Cancer ; 13(2): 485-95, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16728576

RESUMO

Immunocytochemistry (ICC) of thyroid peroxidase (TPO) using the monoclonal antibody MoAb47 has been used as malignancy marker on thyroid fine needle aspiration. However, little is known about the fate of TPO in thyroid carcinoma. We performed a qualitative PCR (Q-PCR) analysis to measure the expression of variants of tpo mRNA in 13 normal tissue samples, 30 benign tumors (BT), 21 follicular carcinomas (FC), 20 classical papillary carcinomas (PCc), 12 follicular variants of papillary carcinomas (PCfv) and nine oncocytic carcinomas (OC). We also studied mutations involving the ras, Braf, ret or pax8 genes. Results of Q-PCR were closely correlated with those of ICC (P < 0.0001; R = 0.59) and showed that overall tpo expression was lower in all carcinomas than in normal and BT (P < 0.05). The ratio tpo2 or tpo3 to tpo1 was inversed in follicular tumors. Genetic mutations were observed in 90% of PCc, 61.9% of FC, 41.7% of PCfv, 0% of OC and 10% in BT. pax8-ppar gamma1 rearrangement was correlated with qualitative changes in tpo mRNA (P < 0.01). These results confirmed the decrease of TPO expression in 97% of thyroid carcinomas regardless of histological type and the overexpression of shorter splice variants in follicular tumors. Both reduction in quantity of TPO and impairment of its maturation process could account for the atypical immunohistochemical reaction of MoAb47 with TPO.


Assuntos
Carcinoma/enzimologia , Regulação Neoplásica da Expressão Gênica , Genes Neoplásicos/genética , Iodeto Peroxidase/genética , Neoplasias da Glândula Tireoide/enzimologia , Adulto , Idoso , Carcinoma/genética , Regulação para Baixo , Feminino , Genes ras/genética , Humanos , Iodeto Peroxidase/análise , Masculino , Pessoa de Meia-Idade , Mutação , Fator de Transcrição PAX8 , Fatores de Transcrição Box Pareados/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas c-ret/genética , RNA Mensageiro/análise , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias da Glândula Tireoide/genética
13.
Br J Cancer ; 84(7): 936-45, 2001 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-11286474

RESUMO

Amphiregulin (AR) is a heparin-binding epidermal growth factor (EGF)-related peptide that seems to play an important role in mammary epithelial cell growth regulation. We have investigated the regulation of AR-gene expression and -protein secretion by EGF in normal breast epithelial cells (HMECs), as well as in the tumoral breast epithelial cell lines MCF-7 and MDA-MB231. EGF induced a dose-dependent increase of AR mRNA level in both normal and tumoral cells. Thus, 10(-8)M EGF stimulated AR expression in HMECs to 140-300% of control. A similar EGF concentration increased AR mRNA level to 550% and 980% of control in MCF-7 and MDA-MB231 cells, respectively. This was accompanied by an accumulation of AR into conditioned culture media. However, HMECs secreted in response to EGF, 5-10 fold more AR than tumour cells. Furthermore, the potential participation of AR in the regulation of the plasminogen activator (PA)/plasmin system was investigated. Whereas HMEC-proliferation was stimulated by AR, the levels of secreted urokinase-type plasminogen activator (uPA) and type-1 plasminogen activator inhibitor (PAi-1) remained unaffected. Conversely, AR failed to regulate the proliferation of tumoral cell lines but induced an accumulation of uPA and PAi-1 into culture media. This was accompanied by an increase of the number of tumoral cells that invaded matrigel in vitro. Moreover, the presence of a neutralizing anti-uPA receptor antibody reversed the increased invasiveness of MDA-MB231 cells induced by AR. These data reveal differential behaviour of normal versus tumoral breast epithelial cells in regard to the action of AR and demonstrate that, in a number of cases, AR might play a significant role in tumour progression through the regulation of the PA/plasmin system.


Assuntos
Adenocarcinoma/metabolismo , Neoplasias da Mama/metabolismo , Mama/metabolismo , Glicoproteínas/fisiologia , Substâncias de Crescimento/fisiologia , Peptídeos e Proteínas de Sinalização Intercelular , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Adenocarcinoma/enzimologia , Adenocarcinoma/patologia , Adolescente , Adulto , Anfirregulina , Mama/citologia , Mama/enzimologia , Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Divisão Celular/fisiologia , Células Cultivadas , Família de Proteínas EGF , Fator de Crescimento Epidérmico/farmacologia , Células Epiteliais/citologia , Células Epiteliais/enzimologia , Células Epiteliais/metabolismo , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/fisiologia , Glicoproteínas/biossíntese , Glicoproteínas/genética , Glicoproteínas/farmacologia , Substâncias de Crescimento/biossíntese , Substâncias de Crescimento/genética , Substâncias de Crescimento/farmacologia , Humanos , Imunofenotipagem , Invasividade Neoplásica , Células Tumorais Cultivadas
14.
Endocrinology ; 139(5): 2382-91, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9564849

RESUMO

Epidermal growth factor (EGF), which plays an important role in normal and tumoral cell growth regulation, displays an ambivalent dose-dependent effect on the proliferation of epithelial cells overexpressing EGF receptor. However, the underlying molecular mechanisms remain obscure. In this study we have examined the regulation of amphiregulin (AR) gene expression by growth inhibitory (10(-9) M) and stimulatory (10(-12) M) EGF concentrations in A431 cells. The time course of AR messenger RNA (mRNA) accumulation was different with 10(-12) and 10(-9) M EGF; AR induction by 10(-9) M EGF peaked between 1 and 1.5 h, then decreased to the basal level within 2 h. Conversely, the induction by 10(-12) M EGF was slightly delayed, but persisted for 4 h. The involvement of tyrosine phosphorylation in AR induction by EGF was suggested by the ability of the tyrosine phosphatase inhibitor sodium orthovanadate to prolong AR expression induced by 10(-12) or 10(-9) M EGF. In the presence of the protein phosphatase 2A inhibitor, okadaic acid, 10(-9) M EGF induced a persistent accumulation of AR mRNA. On the contrary, okadaic acid abrogated the stimulation of AR mRNA level induced by a low EGF concentration, suggesting that both EGF concentrations activated distinct regulatory mechanisms. The signaling components involved in the differential activities of EGF in A431 cells were then examined. We previously reported a relationship between the ambivalent activity of EGF and the p42-mitogen-activated protein (MAP) kinase activity. Thus, 10(-12) M EGF induced a sustained MAP kinase activation, whereas 10(-9) M EGF led to a sharp, but transitory, activation. The MAP kinases are activated by MAP kinase kinases (MEK1 and MEK2). Whereas no significant effect of 10(-12) M EGF could be detected, 10(-9) M EGF was shown to activate MEK1 and, to a lesser extent, MEK2. Also, both MAP kinase activation and AR induction by 10(-9) M, but not by 10(-12) M, EGF were inhibited by the MEK1 inhibitor PD98059. Moreover, the involvement of c-Raf-1 in the signaling pathway induced by EGF was verified. A concentration of 10(-9) M EGF induced stimulation of c-Raf-1 kinase activity, whereas 10(-12) M EGF not only failed to activate c-Raf-1, but led to a moderate decrease in its kinase activity. These results demonstrate that in EGF receptor-overexpressing cells, EGF may differently affect gene expression and cell proliferation through distinct mechanisms of regulation.


Assuntos
Fator de Crescimento Epidérmico/administração & dosagem , Expressão Gênica , Glicoproteínas/genética , Substâncias de Crescimento/genética , Peptídeos e Proteínas de Sinalização Intercelular , Proteínas Proto-Oncogênicas c-raf/metabolismo , Transdução de Sinais , Anfirregulina , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Linhagem Celular , Relação Dose-Resposta a Droga , Ativação Enzimática , Inibidores Enzimáticos/farmacologia , Fator de Crescimento Epidérmico/farmacologia , Cinética , Ácido Okadáico/farmacologia , Fosfoproteínas Fosfatases/antagonistas & inibidores , Proteína Fosfatase 2 , Proteínas Tirosina Fosfatases/antagonistas & inibidores , RNA Mensageiro/biossíntese , Vanadatos/farmacologia
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