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3.
Hand Surg Rehabil ; 41(4): 452-456, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35462049

RESUMO

Hamatolunate impingement syndrome is an uncommon cause of ulnar-sided wrist pain in the general population. Often misdiagnosed and untreated by non-specialized physicians, it is an important source of chronic ulnar wrist pain in golfers. The purpose of this retrospective study was to report results of arthroscopic burring of the apex of the hamate for hamatolunate impingement, whether isolated or not, in golf players, with a minimum of six months follow-up. Fifteen golf players (10 amateur, 2 semi-professional and 3 professional players), aged 40-61 years, with ulnar carpal pain implicating hamatolunate impingement with Viegas type-II carpal configuration, were included. Treatment consisted in arthroscopic burring of the apex of the hamate. At an average follow-up of 11 months (range, 6-24 months), all patients were satisfied with functional results, except 1 with persistent pain and stiffness; 93% returned to sport to their prior level. Mean range of motion was improved by 17 ° for wrist flexion (range, 15 ° to 30 °) and 15 ° for wrist extension (range, 10 ° to 25 °). All patients except 1 recovered grip strength, improving from 27 kg (range, 12-53) preoperatively to 35 kg (range, 17-61) at last-follow-up, and ulnar-sided pain was alleviated during golf practice. Return to prior sport level was possible by 5.5 months for professional players and by 9 months for amateurs. Arthroscopic burring of the apex of the hamate provided good clinical results for function and pain, with fairly rapid return to sport. Hamatolunate chondritis does not always mean pathology but represents the natural progression of Viegas type II wrists.


Assuntos
Ossos do Carpo , Hamato , Artralgia , Ossos do Carpo/cirurgia , Hamato/cirurgia , Humanos , Dor/etiologia , Estudos Retrospectivos , Articulação do Punho/cirurgia
4.
Horm Metab Res ; 41(9): 710-4, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19551609

RESUMO

Receptor tyrosine kinase RET is normally expressed at low levels in chromaffin cells and high levels in sympathetic neurons. Paradoxically, it is overexpressed in subsets of pheochromocytomas. The overexpressed protein is usually wild-type, except in multiple endocrine neoplasia type 2. Possible explanations for overexpression include tumor origin from RET-expressing sympathoadrenal progenitors that escape developmental culling during embryogenesis, or reactivation of signaling pathways related to neuronal differentiation. Normal adult chromaffin and pheochromocytoma cells can undergo neuron-like differentiation in cell culture. In this investigation, cultured cells from two normal human adrenal medullas, two of three human pheochromocytomas, and one extra-adrenal paraganglioma showed RET induction corresponding with extensive nerve growth factor-induced outgrowth of neurite-like processes, while one pheochromocytoma showed neither processes nor RET induction. RET was similarly upregulated in parallel with process outgrowth in cultures of normal rat chromaffin cells and PC12 rat pheochromocytoma cells. In contrast, mouse pheochromocytoma cells that constitutively express high levels of wild-type RET together with other neuronal progenitor markers showed no further RET increase after cyclic AMP-induced process outgrowth. The RET-activating ligand GDNF was anti-apoptotic for mouse pheochromocytoma but not for PC12 cells. The findings suggest that overexpression of RET in pheochromocytomas could result either from a secondary event that activates signaling pathways mediating adult chromaffin cell plasticity or as a component of a persistent sympathoadrenal progenitor phenotype. Whether wild-type RET contributes to tumor development or is merely a lineage marker for cells at various stages of neuronal differentiation may vary, with other tumor characteristics.


Assuntos
Neoplasias das Glândulas Suprarrenais/genética , Células Cromafins/metabolismo , Expressão Gênica , Neurogênese , Neurônios/metabolismo , Feocromocitoma/genética , Proteínas Proto-Oncogênicas c-ret/genética , Neoplasias das Glândulas Suprarrenais/metabolismo , Animais , Diferenciação Celular , Linhagem Celular , Células Cultivadas , Células Cromafins/citologia , Humanos , Camundongos , Neurônios/citologia , Células PC12 , Feocromocitoma/metabolismo , Proteínas Proto-Oncogênicas c-ret/metabolismo , Ratos
5.
Neuroscience ; 147(4): 928-37, 2007 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-17582688

RESUMO

Pheochromocytomas are adrenal medullary tumors that typically occur in adult patients, with increased frequency in multiple endocrine neoplasia type 2, von Hippel-Lindau disease, familial paraganglioma syndromes and neurofibromatosis type 1 (NF1). Pheochromocytomas arise in adult mice with a heterozygous knockout mutation of exon 31 of the murine Nf1 gene, providing a mouse model for pheochromocytoma development in NF1. We performed a microarray-based gene expression profiling study comparing mouse pheochromocytoma tissue to normal adult mouse adrenal medulla to develop a basis for studying the pathobiology of these tumors. The findings demonstrate that pheochromocytomas from adult neurofibromatosis knockout mice express multiple developmentally regulated genes involved in early development of both the CNS and peripheral nervous system. One of the most highly overexpressed genes is receptor tyrosine kinase Ret, which is known to be transiently expressed in the developing adrenal gland, down-regulated in adult adrenals and often overexpressed in human pheochromocytomas. Real-time polymerase chain reaction validated the microarray results and immunoblots confirmed the overexpression of Ret protein. Other highly expressed validated genes include Sox9, which is a neural crest determinant, and Hey 1, which helps to maintain the progenitor status of neural precursors. The findings are consistent with the recently proposed concept that persistent neural progenitors might give rise to pheochromocytomas in adult mouse adrenals and suggest that events predisposing to tumor development might occur before formation of the adrenal medulla or migration of cells from the neural crest. However, the competing possibility that developmentally regulated neural genes arise secondarily to neoplastic transformation cannot be ruled out. In either case, the unique profile of gene expression opens the mouse pheochromocytoma model to new applications pertinent to neural stem cells and suggests potential new targets for treatment of pheochromocytomas or eradication of their precursors.


Assuntos
Neoplasias das Glândulas Suprarrenais/metabolismo , Regulação Neoplásica da Expressão Gênica/fisiologia , Neurofibromina 1/deficiência , Feocromocitoma/genética , Proteínas Proto-Oncogênicas c-ret/metabolismo , Neoplasias das Glândulas Suprarrenais/complicações , Neoplasias das Glândulas Suprarrenais/genética , Animais , Perfilação da Expressão Gênica/métodos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurofibromatose 1/complicações , Neurofibromatose 1/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Feocromocitoma/complicações , Análise de Componente Principal , Proteínas Proto-Oncogênicas c-ret/genética , RNA Mensageiro/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos
6.
Food Chem Toxicol ; 42(6): 887-97, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15110097

RESUMO

In this study, we tested and compared the endocrine disruption activities of compounds in materials used to package foods (bisphenol A, bisphenol F, and bisphenol A diglycidylether BADGE) with natural molecules (genistein, apigenin, kaempferol, and tangeretin) in the human breast cancer cell lines MCF-7 (ER(+)) and MDA-MB453 (AR(+); GR(+)). Octylphenol was also chosen as a xenoestrogen reference. Two compounds had no estrogenic activity: BADGE and tangeretin. Genistein was the most active compound in the E-Screen assay with MCF-7, followed by octylphenol, bisphenol F, bisphenol A and apigenin, with kaempferol the least potent. All estrogenic compounds competed with 17beta-estradiol for binding to the MCF-7 ER and their estrogenic effects were abolished in the presence of tamoxifen, an ER antagonist. In MDA-MB453 cells transfected with pMMTVneo-Luc, all compounds had anti-androgenic activities, with octylphenol the most potent. Kaempferol, genistein, and apigenin were more potent anti-androgens than bisphenols A or F. The natural compounds had a biphasic effect on luciferase activity. At high concentrations, genistein (10(-5)M) and apigenin (10(-6)M) acted as GR agonists in transfected MDA-MB453 cells. Furthermore, apigenin, at a concentration of 10(-5)M, may act as a partial androgen receptor (AR) agonist, as nilutamide, an AR antagonist, inhibited its activity by 26%.


Assuntos
Neoplasias da Mama/patologia , Flavonas , Embalagem de Alimentos , Receptores Androgênicos/efeitos dos fármacos , Receptores de Estrogênio/efeitos dos fármacos , Anticarcinógenos/farmacologia , Antineoplásicos/farmacologia , Apigenina , Compostos Benzidrílicos , Carcinógenos/farmacologia , Relação Dose-Resposta a Droga , Sistema Endócrino/efeitos dos fármacos , Compostos de Epóxi/farmacologia , Estrogênios não Esteroides/farmacologia , Feminino , Flavonoides/farmacologia , Genisteína/farmacologia , Humanos , Quempferóis/farmacologia , Fenóis/farmacologia , Receptores Androgênicos/fisiologia , Células Tumorais Cultivadas
8.
Toxicol Appl Pharmacol ; 172(2): 108-18, 2001 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-11298497

RESUMO

Some phthalates are suspected to disrupt the endocrine system, especially by mimicking estrogens. N-butyl benzyl phthalate (BBP) has estrogenic effects in vitro but not in vivo. The aim of this study was to identify the active molecule(s) (parent compound and/or metabolite(s)) involved in the estrogenic activities of BBP. The estrogenic effects of BBP and its in vivo metabolites were assessed using the following tests: E-Screen, ER binding, and PR induction tests on the human breast cancer cell line MCF-7 (ER(+)). BBP, the parent compound, was a partial agonist. It stimulated MCF-7 proliferation in the E-Screen assay and increased cytosolic progesterone receptors (PR) levels in a concentration-dependent manner. No BBP metabolites were active except hippuric acid (HA), which had a weak effect at very high concentrations. BBP and HA stimulatory effects on MCF-7 proliferation were antagonized by tamoxifen. However, no competition was observed between BBP or HA and 17beta-estradiol for binding to the estrogen receptor (ER). BBP metabolism by MCF-7 cells was also investigated. After a 48-h incubation, only 10% of the initial BBP remained in the culture medium, demonstrating that BBP was extensively metabolized by the MCF-7 cells. The radioactivity recovered in the medium was represented by: mono-n-butyl phthalate (MBuP, 25%) and mono-n-benzyl phthalate (MBeP, 48%), phthalic acid (6%), and benzoic acid (3%). Since none of these metabolites had estrogenic activities, this study demonstrates that the parent compound was the active molecule involved in the in vitro estrogenic effects of BBP.


Assuntos
Estrogênios não Esteroides/metabolismo , Estrogênios não Esteroides/toxicidade , Ácidos Ftálicos/metabolismo , Ácidos Ftálicos/toxicidade , Ligação Competitiva , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Divisão Celular/efeitos dos fármacos , Citosol/metabolismo , Estradiol/metabolismo , Estradiol/toxicidade , Moduladores de Receptor Estrogênico/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Hipuratos/farmacologia , Humanos , Mimetismo Molecular , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/biossíntese , Tamoxifeno/farmacologia , Células Tumorais Cultivadas
9.
Plant Physiol ; 124(1): 379-95, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10982451

RESUMO

A low-molecular weight protein, termed oligandrin, was purified to homogeneity from the culture filtrate of the mycoparasitic fungus Pythium oligandrum. When applied to decapitated tomato (Lycopersicon esculentum Mill. var. Prisca) plants, this protein displayed the ability to induce plant defense reactions that contributed to restrict stem cell invasion by the pathogenic fungus Phytophthora parasitica. According to its N-terminal sequence, low-molecular weight, acidic isoelectric point, ultraviolet spectrum, and migration profile, the P. oligandrum-produced oligandrin was found to share some similarities with several elicitins from other Phytophthora spp. and Pythium spp. However, oligandrin did not induce hypersensitive reactions. A significant decrease in disease incidence was monitored in oligandrin-treated plants as compared with water-treated plants. Ultrastructural investigations of the infected tomato stem tissues from non-treated plants showed a rapid colonization of all tissues associated with a marked host cell disorganization. In stems from oligandrin-treated plants, restriction of fungal growth to the outermost tissues and decrease in pathogen viability were the main features of the host-pathogen interaction. Invading fungal cells were markedly damaged at a time when the cellulose component of their cell walls was quite well preserved. Host reactions included the plugging of intercellular spaces as well as the occasional formation of wall appositions at sites of potential pathogen entry. In addition, pathogen ingress in the epidermis was associated with the deposition of an electron-opaque material in most invaded intercellular spaces. This material, lining the primary walls, usually extended toward the inside to form deposits that frequently interacted with the wall of invading hyphae. In the absence of fungal challenge, host reactions were not detected.


Assuntos
Proteínas de Algas/isolamento & purificação , Proteínas de Transporte , Proteínas Fúngicas/isolamento & purificação , Phytophthora/patogenicidade , Doenças das Plantas/microbiologia , Pythium/química , Solanum lycopersicum/microbiologia , Proteínas de Algas/química , Proteínas de Algas/farmacologia , Sequência de Aminoácidos , Cromatografia Líquida de Alta Pressão , Proteínas Fúngicas/química , Proteínas Fúngicas/farmacologia , Coloide de Ouro , Peptídeos e Proteínas de Sinalização Intercelular , Solanum lycopersicum/ultraestrutura , Microscopia Eletrônica , Dados de Sequência Molecular , Estruturas Vegetais/microbiologia , Estruturas Vegetais/ultraestrutura , Alinhamento de Sequência , Análise de Sequência de Proteína
10.
Appl Environ Microbiol ; 66(10): 4305-14, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11010874

RESUMO

The ubiquitous oomycete Pythium oligandrum is a potential biocontrol agent for use against a wide range of pathogenic fungi and an inducer of plant disease resistance. The ability of P. oligandrum to compete with root pathogens for saprophytic colonization of substrates may be critical for pathogen increase in soil, but other mechanisms, including antibiosis and enzyme production, also may play a role in the antagonistic process. We used transmission electron microscopy and gold cytochemistry to analyze the intercellular interaction between P. oligandrum and Phytophthora parasitica. Growth of P. oligandrum towards Phytophthora cells correlated with changes in the host, including retraction of the plasma membrane and cytoplasmic disorganization. These changes were associated with the deposition onto the inner host cell surface of a cellulose-enriched material. P. oligandrum hyphae could penetrate the thickened host cell wall and the cellulose-enriched material, suggesting that large amounts of cellulolytic enzymes were produced. Labeling of cellulose with gold-complexed exoglucanase showed that the integrity of the cellulose was greatly affected both along the channel of fungal penetration and also at a distance from it. We measured cellulolytic activity of P. oligandrum in substrate-free liquid medium. The enzymes present were almost as effective as those from Trichoderma viride in degrading both carboxymethyl cellulose and Phytophthora wall-bound cellulose. P. oligandrum and its cellulolytic enzymes may be useful for biological control of oomycete pathogens, including Phytophthora and Pythium spp., which are frequently encountered in field and greenhouse production.


Assuntos
Celulase/metabolismo , Controle Biológico de Vetores , Phytophthora/fisiologia , Pythium/fisiologia , Carboximetilcelulose Sódica/metabolismo , Comunicação Celular , Membrana Celular/fisiologia , Membrana Celular/ultraestrutura , Celulose/metabolismo , Pisum sativum/microbiologia , Phytophthora/ultraestrutura , Raízes de Plantas/microbiologia , Pythium/patogenicidade , Pythium/ultraestrutura , Microbiologia do Solo , Virulência
11.
Food Chem Toxicol ; 37(8): 905-17, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10506015

RESUMO

n-Butyl benzyl phthalate (BBP), a plasticizer used in polyvinylchloride (PVC) and other polymers, has been orally administered to female Wistar rats with four doses (150, 475, 780 and 1500 mg/kg body weight/day) for 3 consecutive days. Metabolites recovered in urines were analysed by gas chromatography-mass spectrometry (GC-MS) after 24, 48 and 72 hours. Six metabolites were identified. Mono-n-butyl phthalate (MBuP) and mono-n-benzyl phthalate (MBeP) represented respectively 29-34% and 7-12% of the total recovered metabolites. Hippuric acid, the main metabolite of benzoic acid, represented the second major metabolite (51-56%). Phthalic acid, benzoic acid and an omega-oxidized metabolite of MBuP were also recovered in urine but in small quantities. BBP was never identified in urines. Total urinary metabolites recovery represented 56% of the dose administered in the first 24 hours. However, total recovery decreased when the dose increases (43% at 780 mg/kg body weight/day, only 30% at 1500 mg/kg body weight/day). Whatever the time was, BBP metabolites recovered in urines were all present and in the same proportions for the two lowest doses. Discrepancy in metabolites quantities expressed as percentages of the dose observed in urine of rat treated with the highest BBP dose disappeared with time as MBuP, MBeP and hippuric acid recovery has significantly increased at day 3. Metabolic profile of BBP in female rats has been established. The aim of the present study is to identify further the active(s) agent(s) involved in the BBP malformations and teratogenic effects.


Assuntos
Ácidos Ftálicos/farmacocinética , Plastificantes/farmacocinética , Teratogênicos/farmacocinética , Animais , Diazometano , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Hipuratos/urina , Estrutura Molecular , Oxirredução , Ácidos Ftálicos/química , Ácidos Ftálicos/urina , Ratos , Ratos Wistar
12.
Phytopathology ; 89(6): 506-17, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18944723

RESUMO

ABSTRACT The interaction between the oomycete Pythium oligandrum and various soilborne oomycete and fungal plant pathogens (P. ultimum, P. aphanidermatum, Fusarium oxysporum f. sp. radicis-lycopersici, Verticillium albo-atrum, Rhizoctonia solani, and Phytophthora megasperma) was studied by light and electron microscopy in order to assess the relative contribution of mycoparasitism and antibiosis in the antagonistic process. Scanning electron microscope investigations of the interaction regions showed that structural alterations of all pathogenic fungi and oomycetes (except for Phytophthora megasperma) occurred soon after contact with the antagonist. Light and transmission electron microscope studies of the interaction region between the antagonist and P. ultimum revealed that intimate contact between both partners preceded a sequence of degradation events including aggregation of host cytoplasm and penetration of altered host hyphae. Localization of the host wall cellulose component showed that cellulose was altered at potential penetration sites. A similar scheme of events was observed during the interaction between P. oligandrum and F. oxysporum f. sp. radicis-lycopersici, with the exception that complete loss of host protoplasm was associated with antagonist invasion. The interaction between P. oligandrum and R. solani resulted in an abnormal deposition of a wall-like material at potential penetration sites for the antagonist. However, the antagonist displayed the ability to circumvent this barrier and penetrate host hyphae by locally altering the chitin component of the host hyphal wall. Interestingly, antagonist cells also showed extensive alteration as evidenced by the frequent occurrence of empty hyphal shells. In the case of Phytophthora megasperma, hyphal interactions did not occur, but hyphae of the plant pathogen were damaged severely. At least two distinct mechanisms appear to be involved in the process of oomycete and fungal attack by P. oligandrum: (i) mycoparasitism, mediated by intimate hyphal interactions, and (ii) antibiosis, with alteration of the host hyphae prior to contact with the antagonist. However, the possibility that the antagonistic process may rely on the dual action of antibiotics and hydrolytic enzymes is discussed.

13.
Nutr Cancer ; 32(1): 1-7, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9824849

RESUMO

Monoterpenes are found in the essential oils of many commonly consumed fruits and vegetables. These compounds have been shown to exert chemopreventive and chemotherapeutic activities in mammary tumor models and represent a new class of breast cancer therapeutic agents. In this study, we investigated the effects of limonene and limonene-related monoterpenes, perillyl alcohol and perillic acid, on cell growth, cell cycle progression, and expression of cyclin D1 cell cycle-regulatory gene in T-47D, MCF-7, and MDA-MB-231 breast cancer cell lines. Our results revealed that limonene-related monoterpenes caused a dose-dependent inhibition of cell proliferation. Of the three monoterpenes tested, perillyl alcohol was the most potent and limonene was the least potent inhibitor of cell growth. The enantiomeric composition of limonene and perillyl alcohol did not interfere with their effect on cell growth. Sensitivity of breast cancer cell lines to monoterpenes was in the following order: T-47D > MCF-7 > MDA-MB-231. Growth inhibition induced by perillyl alcohol and perillic acid was associated with a fall in the proportion of cells in the S phase and an accumulation of cells in the G1 phase of the cell cycle. Finally, we showed that the effects of limonene-related monoterpenes on cell proliferation and cell cycle progression were preceded by a decrease in cyclin D1 mRNA levels.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/patologia , Ciclo Celular/efeitos dos fármacos , Ciclina D1/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Monoterpenos , Neoplasias da Mama/metabolismo , Divisão Celular/efeitos dos fármacos , Cicloexenos , Progressão da Doença , Feminino , Humanos , Limoneno , Terpenos/farmacologia , Células Tumorais Cultivadas
15.
Exp Cell Res ; 180(1): 276-80, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2909393

RESUMO

Cultured rat astrocytes were exposed for 1 or 3 h to acidic medium (pH adjusted to 5.0, 5.5, or 6.0). Radioactive labeling for 3 h after exposure to acidic medium revealed increased synthesis of many proteins, including an inducible 68-kDa protein. Optimal extracellular (medium) pH for the induction of this 68-kDa protein was 5.5. Immunoblotting demonstrated that this 68-kDa protein induced by acidosis was the 68-kDa heat-shock protein previously described in cultured astrocytes.


Assuntos
Astrócitos/metabolismo , Proteínas de Choque Térmico/biossíntese , Animais , Células Cultivadas , Meios de Cultura , Temperatura Alta , Concentração de Íons de Hidrogênio , Peso Molecular , Ratos
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