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1.
BMC Pediatr ; 23(1): 180, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-37072747

RESUMO

BACKGROUND: Early detection of developmental delay (DD) in preschool children is crucial for counselling parents, initiating diagnostic work-up, and starting early intervention (EI). METHODS: We conducted a register study of all preschool children referred for EI in the Canton of Zurich, Switzerland, in 2017 (N = 1,785) and used an online survey among primary care physicians (PCPs, N = 271) to evaluate the care service of DD children. RESULTS: PCPs accounted for 79.5% of all referrals by physicians and had correctly referred over 90% of the children in need of EI at an average age of 39.3 months (SD 8.9). In the survey, which represents 59.2% of all pediatricians and 11.3% of all general practitioners in the Canton, PCPs reported performing a mean of 13.5 (range 0-50, SD 10.7) well-child visits per week to preschool children and estimated well-child visits to be the most frequent type of consultation (66.7%) for the identification of DD. Parents' hesitancy in accepting further evaluation or support were reported by 88.7%. CONCLUSIONS: Most preschool children with DD are identified in well-child visits. These visits represent an ideal opportunity for early detection of developmental impairment and initiation of EI. Carefully addressing parents' reservations could reduce the rate of refusal, thus improving early support for children with DD.


Assuntos
Clínicos Gerais , Pais , Humanos , Pré-Escolar , Criança , Exame Físico , Inquéritos e Questionários , Pediatras , Deficiências do Desenvolvimento/diagnóstico
2.
Prep Biochem Biotechnol ; 53(6): 591-598, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36121058

RESUMO

During the last few years, an important element in the improvement of the molecular biology techniques has been the necessity for availability of high quality and functionality DNA. Several DNA extraction procedures with different results in both performance and quality, have been proposed. In this study our objective was to determine the most reliable extraction method that balances DNA quantity, and to assess the sample quantification of the fluorometric DNA quantification methods. For this, blood extracted by venopunction from 20 healthy volunteers was used to obtain DNA from buffy coat, and 4 commercial DNA extraction kits were assessed as well as two fluorometric DNA quantification methods with protocols of different complexity. Results suggest that manual methods achieve higher quality and larger yields of DNA. DNA purity obtained with the 4 extraction kits evaluated through the 260/280 and 260/230 ratio showed that the Qiacube kit fulfilled the criteria established in this work, followed very close by the Flexigene kit. On the other hand, the fluorometric DNA methods used in the samples quantification showed a higher variability when using QuantiFlour method, obtaining better results probably due to the simplicity of this protocol.


Assuntos
Buffy Coat , DNA , Humanos , DNA/isolamento & purificação
3.
Cell Tissue Bank ; 20(2): 255-265, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30903409

RESUMO

Human samples are commonly collected and long-term stored in biobanks for current and future analyses. Even though techniques for freezing human blood are well established, the storage time can compromise the cell viability as well as the yield and quality of nucleic acids (RNA and DNA) extracted from them. In this study, a protocol to obtain peripheral blood mononuclear cells (PBMCs) from 70 subjects, which were stored at - 196 °C from EDTA tubes for a long-term, was assessed. In parallel; a protocol to obtain DNA from the same subjects, which were stored at - 80 °C from citrate tubes, was also studied. Samples stored from 2008 to 2012 were studied and the results obtained showed that there were no statistically significant differences in the RNA or DNA extracted in terms of purity, integrity and functionality The freezing protocol used by the Málaga Biobank shows that viable PBMCs and DNA could be kept for a period of, at least, 10 years, with a high quality and performance. Furthermore, RNA extracted from these PBMCs presents also a good quality and performance. Therefore, the samples frozen according to the conditions of the protocols assessed in this study could be optimal for biomedical research.


Assuntos
Criopreservação/métodos , DNA/análise , Leucócitos Mononucleares/citologia , RNA/análise , Bancos de Sangue , Sobrevivência Celular , Humanos , Espanha , Bancos de Tecidos
4.
J Comp Pathol ; 179: 52-58, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32958148

RESUMO

While the health effects of trypanosomes in Australian mammals in their native range are not fully understood, there is evidence of an impact in those species introduced to other geographical regions. Here we report the pathological and molecular features of concurrent fatal trypanosomiasis and toxoplasmosis in an adult female captive red-necked wallaby (syn. Bennett's wallaby; Macropus rufogriseus) from Bee County, Texas, USA. The animal exhibited no clinical signs prior to sudden death. On necropsy, the main findings were generalized organ congestion and bilateral renal petechiation. Microscopically, the main finding was lymphohistiocytic and necrotizing pancarditis with intrasarcoplasmic protozoal pseudocysts containing amastigotes and occasional intrahistiocytic amastigotes, morphologically compatible with Trypanosoma cruzi, as well as rare intrasarcoplasmic protozoal tissue cysts with zoites morphologically compatible with Toxoplasma gondii. Other lesions included acute centrilobular to panlobular necrotizing hepatitis with intrahepatocellular T. gondii cysts, necrotizing splenitis, pulmonary oedema with fibrin, histiocytosis and rare fibrin microthrombi, and acute renal tubular degeneration with proteinosis and pigmented casts suggestive of haemoglobinuria or myoglobinuria. Immunohistochemical labelling confirmed intralesional T. gondii cysts and molecular analyses identified T. cruzi genotype I and T. gondii. This is a unique case that, to the best of our knowledge, represents the first description of T. cruzi and T. gondii co-infection, as well as the first record of naturally occurring infection T. cruzi genotype I infection in macropodids. This case adds to the epidemiological knowledge on Chagas disease in the USA, particularly in Texas where there is a high prevalence of human and canine trypanosomiasis.


Assuntos
Doença de Chagas/veterinária , Coinfecção/veterinária , Macropodidae , Toxoplasmose Animal , Animais , Feminino
5.
J Fish Dis ; 32(2): 143-50, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18803582

RESUMO

Immunohistochemistry (IHC) and in situ hybridization (ISH) techniques have been used for the detection of lymphocystis disease virus (LCDV) in formalin-fixed, paraffin-embedded tissues from gilt-head seabream, Sparus aurata L. Diseased and recovered fish from the same population were analysed. IHC was performed with a polyclonal antibody against a 60-kDa viral protein. A specific digoxigenin-labelled probe, obtained by PCR amplification of a 270-bp fragment of the gene coding the LCDV major capsid protein, was used for ISH. LCDV was detected in skin dermis and gill lamellae, as well as in several internal organs such as the intestine, liver, spleen and kidney using both techniques. Fibroblasts, hepatocytes and macrophages seem to be target cells for virus replication. The presence of lymphocystis cells in the dermis of the skin and caudal fin, and necrotic changes in the epithelium of proximal renal tubules were the only histological alterations observed in fish showing signs of the disease.


Assuntos
Infecções por Vírus de DNA/veterinária , Doenças dos Peixes/patologia , Doenças dos Peixes/virologia , Pesqueiros/métodos , Hibridização In Situ/veterinária , Iridoviridae/fisiologia , Dourada/virologia , Animais , Proteínas do Capsídeo/imunologia , Infecções por Vírus de DNA/patologia , Infecções por Vírus de DNA/virologia , Genoma Viral , Imuno-Histoquímica , Hibridização In Situ/métodos
6.
Drug Test Anal ; 9(7): 1011-1016, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27717280

RESUMO

Since the appearance of recombinant human growth hormone (rhGH) in the 1980s, its expansion and acquisition through the black market has increased, so the detection of its abuse continues to be a challenge. New biomarkers that are more reliable and sensitive, allowing a larger detection window, are still needed. In this line, Fibronectin 1 (FN1) has been proposed as a potential genetic and protein biomarker of rhGH abuse in peripheral blood lymphocytes, serum, and plasma. However, logistic problems associated with current blood collection in sports drug testing point towards potential new alternative matrices that could be good candidates to be evaluated. Results obtained in this study showed high ELISA FN1 levels in one dried blood spot and in urine samples in ten healthy male volunteers treated with rhGH. Results showed that especially dried blood spots appear as a potential good matrix to detect rhGH abuse by means of FN1 biomarker. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Citocinas/sangue , Teste em Amostras de Sangue Seco/métodos , Hormônio do Crescimento Humano/administração & dosagem , Detecção do Abuso de Substâncias/métodos , Adulto , Dopagem Esportivo , Ensaio de Imunoadsorção Enzimática/métodos , Exercício Físico , Feminino , Fibronectinas , Hormônio do Crescimento Humano/sangue , Humanos , Masculino , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/sangue , Adulto Jovem
7.
Drug Test Anal ; 9(1): 87-95, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26811125

RESUMO

Growth hormone releasing peptides (GHRPs) could be widely used by cheating athletes because they produce growth hormone (GH) secretion, so may generate an ergogenic effect in the body. Knowledge of the essential amino acids needed in GHRP structure for interaction with the target biological receptor GHSR1a, the absorption through different administration routes, and the maintenance of pharmacological activity of potential biotransformation products may help in the fight against their abuse in sport. Several GHRPs and truncated analogues with the common core Ala-Trp-(D-Phe)-Lys have been studied with a radio-competitive assay for the GHSR1a receptor against the radioactive natural ligand ghrelin. Relevant chemical modifications influencing the activity for positions 1, 2, 3, and 7 based on the structure aa-aa-aa-Ala-Trp-(D-Phe)-Lys have been obtained. To test in vivo the applicability of the activities observed, the receptor assay activity in samples from excretion studies performed after nasal administration of GHRP-1, GHRP-2, GHRP-6, Hexarelin, and Ipamorelin was confirmed. Overall results obtained allow to infer structure-activity information for those GHRPs and to detect GHSR1a binding (intact GHRPs plus active metabolites) in excreted urines. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Substâncias de Crescimento/farmacologia , Oligopeptídeos/farmacologia , Receptores de Grelina/metabolismo , Dopagem Esportivo , Substâncias de Crescimento/administração & dosagem , Substâncias de Crescimento/química , Substâncias de Crescimento/urina , Células HEK293 , Humanos , Masculino , Oligopeptídeos/administração & dosagem , Oligopeptídeos/química , Oligopeptídeos/urina , Relação Estrutura-Atividade
8.
J Exp Clin Cancer Res ; 25(1): 65-72, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16761620

RESUMO

Human mammaglobin (hMAM) has recently been recognized as a breast associated glycoprotein. Although the biological role of hMAM is unknown, it has been previously reported that hMAM gene expression is a marker of low biological and clinical aggressiveness of breast cancer (BC). In this study, 148 cases of BC tissues were investigated for hMAM mRNA expression by reverse transcriptase-polymerase chain reaction (RT-PCR). In order to evaluate its prognostic value, hMAM was correlated with age of patients, type and size of tumor, nodal stage, histologic grade, c-erbB-2 over expression, Ki67 labelling index, estrogen receptor (ER) status and progesterone receptor (PGR) status. Fisher's exact test was used to examine the association between different parameters and hMAM. hMAM was expressed in 138/148 (93%) of BC tissues examined. Among the 10 hMAM negative cases, 8 were invasive ductal carcinomas (microscopically higher G3 grade) and 2 infiltrating lobular carcinomas. We found a significant association (p = 0.020) between absence of hMAM mRNA and G3 histologic grade but not with any other prognostic parameters studied. The present study indicates that lack of hMAM expression is restricted to the BC with G3 grading. Further studies are needed to clarify the biological basis and the clinical significance of our results.


Assuntos
Neoplasias da Mama/metabolismo , Regulação Neoplásica da Expressão Gênica , Proteínas de Neoplasias/biossíntese , Uteroglobina/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Ductal de Mama/metabolismo , Carcinoma Ductal de Mama/patologia , Linhagem Celular Tumoral , Feminino , Humanos , Antígeno Ki-67/biossíntese , Mamoglobina A , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , RNA Mensageiro/metabolismo , Receptores de Progesterona/metabolismo , Uteroglobina/genética , Uteroglobina/metabolismo
9.
J Pharm Biomed Anal ; 128: 111-118, 2016 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-27243825

RESUMO

Human Growth Hormone (hGH, somatotropin) is one of the relevant forbidden substances to be detected in sport drug testing. Since the appearance of recombinant hGH (rhGH) in the 80's, its expansion and availability through the black market have increased, so the detection of its abuse continues to be a challenge at present. New techniques or biomarkers that are robust, reliable, sensitive and allowing a large detection time window are welcome. rhGH produces an increase of insulin-like growth factor 1 (IGF-1). FN1 (fibronectin 1) and RAB31 (member of RAS oncogene family) genes have been suggested as two potential biomarkers for IGF-1 abuse. Following this line, in the present study some genetic and proteomic approaches have been performed with fourteen healthy male subjects treated with rhGH (which produces increase of IGF-1 concentrations) to study FN1 gene, FN1 protein, RAB31 gene and RAB31 protein as potential biomarkers for rhGH abuse. The results showed that both, RAB31 and FN1 genes and FN1 protein could be potential biomarkers for rhGH administration. Preliminary assessments of gender, age, acute sport activities and GHRP-2 (pralmorelin, a rhGH releasing peptide) influence suggest they are not relevant confounding factors. Thus, the selected markers present high sensitivity and a larger detection window for rhGH detection than IGF-1 itself.


Assuntos
Biomarcadores/sangue , Hormônio do Crescimento Humano/sangue , Adulto , Bioensaio/métodos , Dopagem Esportivo/métodos , Feminino , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Proteômica/métodos , Proteínas Recombinantes/sangue , Esportes , Detecção do Abuso de Substâncias/métodos , Adulto Jovem
10.
Arq. bras. med. vet. zootec. (Online) ; 73(5): 1217-1224, Sept.-Oct. 2021. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1345258

RESUMO

This work aimed to assess the effect of the probiotic strain, Lactobacillus plantarum, on the levels of leptin, IGF-1 and their receptors on the hepatopancreatic tissues of Nile tilapia (Oreochromis niloticus) and then correlate fish growth performance and gut microbiological parameters. Fish juveniles (±23g) were reared in a recirculation system with constant aeration and temperature (25°C). They were distributed into six polyethylene tanks (45L) and fed twice a day at 5% of the tank biomass with the respective diets: control (commercial diet without probiotic) and supplemented with L. plantarum inoculum (1 x 108 CFU mL-1), both in triplicate. After 30 days of feeding, L. plantarum-fed fishes showed greater weekly growth rate, final weight, and feed conversion rate, in addition to higher count of lactic-acid bacteria and lower count of pathogenic bacteria in the intestinal tract, when compared to the control group. The immunostaining intensity for IGF-1 and leptin hormones was lower after L. plantarum supplementation than in the control group, with no change in the level for receptors. This reduction could implicate important changes in fish metabolism and homeostasis.(AU)


O presente trabalho teve como objetivo avaliar o efeito da cepa probiótica Lactobacillus plantarum sobre os níveis de leptina, IGF-1 e seus receptores no tecido hepatopancreático de tilápia-do-nilo (Oreochromis niloticus) e correlacionar com o desempenho zootécnico e os parâmetros microbiológicos intestinais dos peixes. Juvenis de tilápia-do-nilo (±23g) foram distribuídos em seis tanques de polietileno (45L) conectados a um sistema de recirculação, com aeração e temperatura constantes (25°C). Os peixes foram alimentados duas vezes ao dia, a 5% da biomassa do tanque, com as respectivas dietas: controle (dieta comercial sem probiótico) e suplementada com L. plantarum (1 x 108 UFC mL-1), ambas em triplicata. Após 30 dias de cultivo, os peixes alimentados com L. plantarum apresentaram maiores ganho de peso semanal, peso final e conversão alimentar, bem como maior contagem de bactérias ácido-láticas e menor contagem de bactérias patogênicas no trato intestinal das tilápias alimentadas com dieta probiótica, em comparação ao grupo controle. A intensidade da imunomarcação para os hormônios IGF-1 e leptina foi menor com a suplementação de L. plantarum do que no grupo controle, sem alterar os níveis de seus receptores. Essa redução pode implicar mudanças importantes no metabolismo e na homeostase dos peixes.(AU)


Assuntos
Animais , Ciclídeos/crescimento & desenvolvimento , Hepatopâncreas/química , Lactobacillus plantarum , Microbioma Gastrointestinal , Ração Animal , Fator de Crescimento Insulin-Like I , Suplementos Nutricionais , Leptina
11.
Arch Gen Psychiatry ; 36(12): 1283-94, 1979 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-227340

RESUMO

The ability of long-acting fluphenazine decanoate and oral fluphenazine hydrochloride to forestall relapse among newly discharge schizophrenic patients is examined in the context of high and low degrees of social therapy (ST). A total of 105 patients were randomly assigned to the various treatments and maintained under controlled conditions for two years or until relapse. Relapse rates for all treatments remained traditionally high. Relpase rates for long-acting fluphenazine decanoate and oral fluphenazine hydrochloride are nearly identical in the first year, indicating that drug noncompliance does not adequately explain early schizophrenic relapse. However, patients who received long-acting fluphenazine decanoate and ST have a reduced risk of relapse over time. Relapsers who received long-acting fluphenazine decanoate appeared more affectively disturbed than other relapsers, yet both groups were diagnostically and symptomatically equivalent prior to treatment. Personal discomfort and intrafamilial stress are important predictors.


Assuntos
Assistência ao Convalescente , Flufenazina/administração & dosagem , Esquizofrenia/reabilitação , Terapia Socioambiental , Administração Oral , Adolescente , Adulto , Preparações de Ação Retardada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pacientes Desistentes do Tratamento , Probabilidade , Escalas de Graduação Psiquiátrica , Distribuição Aleatória , Recidiva , Esquizofrenia/tratamento farmacológico , Fatores de Tempo
12.
Int J Food Microbiol ; 98(3): 309-18, 2005 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-15698692

RESUMO

Functionally, the innate immune system of immature chickens is inefficient during the first week posthatch. This immunological inefficiency enables pathogens such as Salmonella enterica serovar Enteritidis (SE) to invade and colonize the visceral organs of immature chickens. The objective of this study was to evaluate the effect of purified beta-glucan as an immunomodulator of the innate immune response. beta-glucan, as a feed additive, significantly provided protection against SE organ invasion in young chickens (P<0.05). The functional efficiency of heterophils isolated from neonatal chickens fed a beta-glucan ration was significantly (P<0.05) up-regulated when compared to heterophils isolated from chickens fed a control ration as determined with an array of functional assays. Phagocytosis, bactericidal killing, and oxidative burst were significantly increased in heterophils isolated from chickens fed the purified beta-glucan ration (P<0.05). To our knowledge, this is the first report of a purified beta-glucan feed additive significantly decreasing the incidence of SE organ invasion in immature chickens and up-regulating the functional abilities of heterophils isolated from immature chickens against an invading pathogen, SE.


Assuntos
Galinhas , Imunidade Inata , Salmonelose Animal/imunologia , Salmonella enteritidis/imunologia , beta-Glucanas/administração & dosagem , Administração Oral , Ração Animal , Animais , Animais Recém-Nascidos/imunologia , Masculino , Especificidade de Órgãos , Fagocitose , Distribuição Aleatória , Salmonelose Animal/prevenção & controle , beta-Glucanas/farmacologia
13.
J Exp Clin Cancer Res ; 24(2): 265-71, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16110760

RESUMO

Occult carcinoma cells in peripheral blood of breast cancer (BC) patients is generally associated with poor disease prognosis. Reverse transcriptase-polymerase chain reaction (RT-PCR) is a sensitive method for revealing rare circulating cancer cells. The target mRNA must be carefully chosen, as it must be expressed only by malignant cells. In this study, we developed a nested RT-PCR assay for mammaglobin (hMAM) and assessed both its specificity and its sensitivity in the detection of cancer cells in peripheral blood of BC patients. hMAM mRNA was detected by RT-PCR in 156/165 (95%) of fresh BC tissues analyzed. All samples from 66 healthy blood donors and 151 patients with benign breast disease were hMAM negative as assessed by nested RT-PCR. In contrast, hMAM was detected in 16/137 (12%) of peripheral blood samples deriving from BC patients: 0/9 in stage 0, 1/50 (2%) in stage I, 3/33 (9%) in stage II, 1/18 (5%) in stage III and 11/27 (41%) in stage IV. Using nested RT-PCR, we were able to amplify hMAM transcript of one tumour cell/10(6) normal cells. Our data demonstrate that hMAM mRNA detection by RT-PCR is a specific assay potentially suitable for identification of occult cancer cells in peripheral blood of BC patients.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias da Mama/sangue , Neoplasias da Mama/diagnóstico , Proteínas de Neoplasias/biossíntese , Células Neoplásicas Circulantes/patologia , RNA Mensageiro/metabolismo , Uteroglobina/biossíntese , Linhagem Celular Tumoral , Humanos , Mamoglobina A , Sangue Oculto , Reação em Cadeia da Polimerase , Prognóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sensibilidade e Especificidade
14.
J Biomol Screen ; 20(10): 1268-76, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26160832

RESUMO

The everlasting pharmacological development is continuously producing new substances with potential doping abuse. Among these, secretagogues are very prone to misuse by athletes for their properties to release growth hormone (GH) and some limitations in the actual analytical methods to detect them. In this paper, an in-depth study on the key variables of the radio receptor method previously developed by our group is performed and a fit-for-purpose protocol is established. Thus, this sensitive and robust screening method is proposed as an intelligent and preventive antidoping method to detect new growth hormone secretagogues (GHSs) in exceptional suspicious urine samples obtained from athletes and will support the current detection methods based on liquid chromatography-mass spectrometry (LC-MS).


Assuntos
Dopagem Esportivo , Glicoproteínas/urina , Hormônio do Crescimento/urina , Substâncias para Melhoria do Desempenho/urina , Ligação Competitiva , Cromatografia Líquida , Cromatografia Gasosa-Espectrometria de Massas , Grelina/metabolismo , Células HEK293 , Humanos , Espectrometria de Massas , Receptores de Grelina/metabolismo
15.
Br J Pharmacol ; 121(8): 1531-40, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9283685

RESUMO

1. The effects of the voltage-dependent calcium channel (VDCC) blockers omega-agatoxin IVA (omega-AgaIVA), omega-conotoxin GVIA (omega-CgTx), omega-conotoxin MVIIC (omega-MVIIC) and omega-conotoxin MVIID (omega-MVIID) were evaluated on transmitter release in the mouse diaphragm preparation. The effects of omega-AgaIVA and omega-MVIIC were also evaluated on the perineurial calcium and calcium-dependent potassium currents, ICa and IK(Ca), respectively, in the mouse levator auris preparation. 2. The P- and Q-type VDCC blocker omega-AgaIVA (100 nM) and P- Q- and N-type channel blockers omega-MVIIC (1 microM) and omega-MVIID (3 microM) strongly reduced transmitter release (> 80-90% blockade) whereas the selective N-type channel blocker omega-CgTx (5 microM) was ineffective. 3. The process of release was much more sensitive to omega-MVIIC (IC50 = 39 nM) than to omega-MVIID (IC50 = 1.4 microM). After almost completely blocking transmitter release (quantal content approximately 0.3% of its control value) with 3 microM omega-MVIIC, elevating the external [Ca2+] from 2 to 10 mM induced an increase of approximately 20 fold on the quantal content of the endplate potential (e.p.p.) (from 0.2 +/- 0.04 to 4.8 +/- 1.4). 4. Nerve-evoked transmitter release in a low Ca(2+)-high Mg2+ medium (low release probability, quantal content = 2 +/- 0.1) had the same sensitivity to omega-AgaIVA (IC50 = 16.8 nM) as that in normal saline solutions. In addition, K(+)-evoked transmitter release was also highly sensitive to the action of this toxin (IC50 = 11.5 nM; 100 nM > 95% blockade). The action of omega-AgaIVA on transmitter release could be reversed by toxin washout if the experiments were carried out at 31-33 degrees C. Conversely, the effect of omega-AgaIVA persisted even after two hours of toxin washout at room temperature. 5. Both the calcium and calcium-dependent potassium presynaptic currents, ICa and IK(Ca), respectively, were highly sensitive to low concentrations (10-30 nM) of omega-AgaIVA. The ICa and the IK(Ca) were also strongly reduced by 1 microM omega-MVIIC. The most marked difference between the action of these two toxins was the long incubation times required to achieve maximal effects with omega-MVIIC. 6. In summary these results provide more evidence that synaptic transmission at the mammalian neuromuscular junction is mediated by Ca2+ entry through P- and/or Q-type calcium channels.


Assuntos
Bloqueadores dos Canais de Cálcio/farmacologia , Junção Neuromuscular/efeitos dos fármacos , Neurotoxinas/farmacologia , Neurotransmissores/metabolismo , Peptídeos/farmacologia , Venenos de Aranha/farmacologia , Animais , Canais de Cálcio/efeitos dos fármacos , Masculino , Camundongos , Junção Neuromuscular/fisiologia , Potássio/farmacologia , Canais de Potássio/efeitos dos fármacos , ômega-Agatoxina IVA , ômega-Conotoxina GVIA
16.
Int J Oncol ; 18(6): 1293-7, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11351265

RESUMO

The region on chromosome 7q21-22 is frequently altered in several human neoplasias such as uterine leiomyoma, myeloid leukemia and breast cancer. The same region has also been linked to split hand/split foot malformation type 1 and to involutional osteoporosis. Our analysis of genes that map to this region has led to the identification of the so far unknown first exon of the homeobox gene DLX6, a mammalian homologue of the Drosophila distal-less gene. Distal-less is a downstream target of the trithorax transcription factors. Translocations involving the mammalian homologue of trithorax, ALL-1, leading to its constitutive activation cause leukemia. We describe here that the first exons of human and mouse DLX6 genes contain a multiple trinucleotide repeat region. We have analyzed the CAG repeat length in 90 subjects and were able to identify five alleles with 11 to 20 CAG repeats.


Assuntos
Proteínas de Homeodomínio/genética , Repetições de Trinucleotídeos , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA/análise , Primers do DNA/química , Éxons/genética , Humanos , Camundongos , Dados de Sequência Molecular , Polimorfismo Genético , Biossíntese de Proteínas , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico
17.
Cancer Genet Cytogenet ; 123(1): 35-40, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11120331

RESUMO

The human androgen receptor gene contains a polymorphic CAG repeat region ranging from 8 to about 35 repeats in the normal human population. The repeat length is inversely related to the transactivation potential of the receptor. We have analyzed the repeat length in 50 sporadic colon cancer samples in comparison to surrounding healthy mucosa and have found somatic reductions of up to 10 repeats in 5 cases (10%), 3 of which were complex, probably involving both alleles. Alterations occurred in tumors with and without microsatellite instability indicating that they follow an independent mutation pathway. The similar repeat of the huntingtin gene did not show any somatic alterations in the same cases. No correlation to sex, tumor stage, location, or histology was evident. In the tumors that showed somatic reductions, the reduced allele was present in at least half of the cells and thus in most, if not all, of the tumor component of the sample. Somatic reductions of the androgen receptor CAG repeat thus occur frequently, through a pathway distinct from microsatellite instability and early during colon carcinogenesis. The receptor is expressed in most normal and neoplastic tissue samples analyzed. Apparent growth selection of cells bearing shortened AR alleles suggests that androgens contribute to colon carcinogenesis in a yet unknown way.


Assuntos
Neoplasias do Colo/genética , Repetições de Microssatélites/genética , Receptores Androgênicos/genética , Repetições de Trinucleotídeos/genética , Alelos , Neoplasias do Colo/patologia , Análise Mutacional de DNA , DNA de Neoplasias/química , DNA de Neoplasias/genética , Feminino , Frequência do Gene , Humanos , Masculino , Mutação
18.
Brain Res Bull ; 56(3-4): 259-64, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11719259

RESUMO

Expansions of poly-glutamine tracts in proteins that are expressed in the central nervous system cause neurodegenerative diseases. The altered proteins accumulate over long periods of time, forming nuclear inclusions, and lead to neuronal cell death. A similar mechanism could also be operant in non-dividing cells outside the central nervous system because nuclear inclusions are not limited to neurons. In addition, variations of the repeat length within the normal range may affect cellular function as it has been shown for the androgen receptor that is involved in neoplastic degeneration of several tissues. We have identified a poly-glutamine/poly-proline repeat in the homeobox gene DLX6. DLX genes are expressed in non-proliferative cells of the apical ectodermal ridge of developing limbs. Ablation of these cells leads to limb malformation. We propose that CAG triplet expansions in this gene could lead to cell death in the apical ectodermal ridge causing limb malformations. Indeed, autosomal dominant limb malformations with increasing severity in successive generations have been linked to the chromosomal region that contains DLX6. The analysis of a limited number of patients affected by split hand/foot malformation so far revealed only a slight modifier effect of repeat length within the normal range and no expansions have been detected.


Assuntos
Proteínas de Homeodomínio/genética , Peptídeos/genética , Expansão das Repetições de Trinucleotídeos , Animais , Sistema Nervoso Central , Deformidades Congênitas do Pé/genética , Regulação da Expressão Gênica no Desenvolvimento , Deformidades Congênitas da Mão/genética , Humanos
19.
J Neuroradiol ; 23(3): 139-48, 1996 Dec.
Artigo em Francês | MEDLINE | ID: mdl-9091606

RESUMO

Ten cases of spontaneous dissection of the cerebral arteries are reported. 3 males and 7 females aged 6 to 60 years (mean age 30 years) were investigated in the Department of Neuroradiology of Toulouse between 1989 and 1994 with CT, angiography and MRI. In 5 cases the dissection involved the carotid artery, in 5 cases the vertebro-basilar system. The clinical presentation was of two types: ischaemic stroke (7 cases) or subarachnoid haemorrhage (3 cases). Their evolution is never lethal, contrary to the classical descriptions of the literature. In all cases an initial angiography then follow up has been performed showing an irregular located arterial stenosis. The diagnosis of intracranial dissection is sometimes made in front of a dissequant aneurysm. In case of doubt, magnetic resonance (MR) imaging is helpful showing a linear hypersignal parallel to an arterial segmental stenosis, and angiography MR an irregular aspect and stenosis of the endoluminal artery.


Assuntos
Dissecção Aórtica/diagnóstico , Aneurisma Intracraniano/diagnóstico , Adolescente , Adulto , Artéria Basilar/patologia , Isquemia Encefálica/diagnóstico , Doenças das Artérias Carótidas/diagnóstico , Angiografia Cerebral , Doenças Arteriais Cerebrais/diagnóstico , Transtornos Cerebrovasculares/diagnóstico , Criança , Constrição Patológica/diagnóstico , Feminino , Seguimentos , Humanos , Angiografia por Ressonância Magnética , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Ruptura Espontânea , Hemorragia Subaracnóidea/diagnóstico , Tomografia Computadorizada por Raios X , Artéria Vertebral/patologia
20.
J Radiol ; 77(3): 201-4, 1996 Mar.
Artigo em Francês | MEDLINE | ID: mdl-8830145

RESUMO

Adventitial cystic disease of the popliteal artery is a rare cause of calf claudication in young patients. A case explored by magnetic resonance imaging is reported: a water rich mass around the popliteal artery compressed the arterial lumen. Treatment consisted in CT-guided percutaneous aspiration. Good functional outcome except for severe efforts, despite persistance of cystic images was observed. Echography, computed tomography or magnetic resonance imaging are more useful to establish the diagnosis than arteriography because these techniques can directly visualize the arterial wall. Percutaneous treatment preserves the intima and can be performed in out-patients. When feasible, it could be preferred to conventional surgery.


Assuntos
Cisto Popliteal/diagnóstico , Adulto , Biópsia por Agulha , Diagnóstico Diferencial , Humanos , Claudicação Intermitente/etiologia , Claudicação Intermitente/cirurgia , Imageamento por Ressonância Magnética , Masculino , Cisto Popliteal/diagnóstico por imagem , Cisto Popliteal/cirurgia , Tomografia Computadorizada por Raios X
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