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1.
J Anim Sci ; 93(5): 2021-33, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26020298

RESUMO

Uterine contamination with bacteria is ubiquitous in the postpartum dairy cow. Nearly one-half of all postpartum dairy cows develop clinical disease resulting in metritis and endometritis, which cause depressed milk production and infertility. The causative links between uterine infection and infertility include a hostile uterine environment, disrupted endocrine signaling, and perturbations in ovarian function and oocyte development. In this review we consider the various mechanisms linking uterine infection with infertility in the dairy cow, specifically 1) innate immune signaling in the endometrium, 2) alteration in endocrine signaling in response to infectious agents, and 3) impacts of infection on ovarian function, oocyte development, and follicular development. Normal ovarian follicular and oocyte development requires a series of temporally and spatially orchestrated events; however, several of the cellular pathways required for ovarian function are also used during the innate immune response to bacterial pathogens. We propose that activation of cellular pathways during this immune response has a negative impact on ovarian physiology, which is manifest as infertility detected after the clearance of the bacteria. This review highlights how new insights into infection and immunity in cattle are linked to infertility.


Assuntos
Doenças dos Bovinos/imunologia , Doenças dos Bovinos/microbiologia , Endometrite/veterinária , Imunidade Inata/imunologia , Infertilidade Feminina/veterinária , Período Pós-Parto/imunologia , Animais , Bovinos , Endometrite/complicações , Endometrite/imunologia , Feminino , Infertilidade Feminina/etiologia , Infertilidade Feminina/imunologia
2.
Br J Pharmacol ; 171(10): 2659-70, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24116661

RESUMO

BACKGROUND AND PURPOSE: Identifying and characterizing potential new therapeutic agents to target cell proliferation may provide improved treatments for neoplastic disorders such as cancer and polycystic diseases. EXPERIMENTAL APPROACH: We used the simple, tractable biomedical model Dictyostelium to investigate the molecular mechanism of naringenin, a dietary flavonoid with antiproliferative and chemopreventive actions in vitro and in animal models of carcinogenesis. We then translated these results to a mammalian kidney model, Madin-Darby canine kidney (MDCK) tubule cells, grown in culture and as cysts in a collagen matrix. KEY RESULTS: Naringenin inhibited Dictyostelium growth, but not development. Screening of a library of random gene knockout mutants identified a mutant lacking TRPP2 (polycystin-2) that was resistant to the effect of naringenin on growth and random cell movement. TRPP2 is a divalent transient receptor potential cation channel, where mutations in the protein give rise to type 2 autosomal dominant polycystic kidney disease (ADPKD). Naringenin inhibited MDCK cell growth and inhibited cyst growth. Knockdown of TRPP2 levels by siRNA in this model conferred partial resistance to naringenin such that cysts treated with 3 and 10 µM naringenin were larger following TRPP2 knockdown compared with controls. Naringenin did not affect chloride secretion. CONCLUSIONS AND IMPLICATIONS: The action of naringenin on cell growth in the phylogenetically diverse systems of Dictyostelium and mammalian kidney cells, suggests a conserved effect mediated by TRPP2 (polycystin-2). Further studies will investigate naringenin as a potential new therapeutic agent in ADPKD.


Assuntos
Antiprotozoários/farmacologia , Proliferação de Células/efeitos dos fármacos , Dictyostelium/efeitos dos fármacos , Flavanonas/farmacologia , Rim/efeitos dos fármacos , Rim Policístico Autossômico Dominante/metabolismo , Proteínas de Protozoários/efeitos dos fármacos , Canais de Cátion TRPP/efeitos dos fármacos , Animais , Dictyostelium/genética , Dictyostelium/crescimento & desenvolvimento , Dictyostelium/metabolismo , Cães , Relação Dose-Resposta a Droga , Rim/metabolismo , Rim/patologia , Células Madin Darby de Rim Canino , Mutação , Rim Policístico Autossômico Dominante/genética , Rim Policístico Autossômico Dominante/patologia , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Interferência de RNA , Canais de Cátion TRPP/genética , Canais de Cátion TRPP/metabolismo , Fatores de Tempo , Transfecção
3.
Rev Sci Instrum ; 82(2): 025112, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21361638

RESUMO

The paper describes the development, implementation, and testing of two thermally driven outdoor exposure instruments. These devices are unique in their ability to impose field generated thermally induced strain on sealant specimens while monitoring their resulting load and displacement. The instruments combine a fixed wood and steel supporting frame with a moving polyvinyl chloride frame, and employ differences in the coefficients of thermal expansion between the supporting frame and moving frame to induce strain on the sealant specimens. Two different kinds of instruments have been fabricated, "winter/tension" and "winter/compression" designs. In the winter/tension design, the thermally induced dimensional change is directly transferred to the specimens; while in the winter/compression design, the samples are loaded in an opposite direction with the dimensional change. Both designs are instrumented to monitor load and displacement and are built so that the strain on the specimen does not exceed ±25% over the range of temperatures expected in Gaithersburg, MD. Additionally, a weather station is colocated with the device to record environmental conditions in 1 min intervals. This combination of weather information with mechanical property data enables a direct link between environmental conditions and the corresponding sealant response. The reliability and effectiveness of these instruments are demonstrated with a typical sealant material. The results show that the instruments work according to the design criteria and provide a meaningful quantitative platform to monitor the mechanical response of sealant exposed to outdoor weathering.

4.
Pain ; 152(3): 614-622, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21239109

RESUMO

Studies have demonstrated menstrual cycle influences on basal pain perception, but direct evidence of menstrual cycle influences on analgesic responses has not been reported in humans. Our aim was to determine whether the magnitude of morphine and pentazocine analgesia varied across the menstrual cycle. Sixty-five healthy women, 35 taking oral contraceptives (OC) and 30 normally cycling (NOC), underwent experimental pain assessment both before and after intravenous administration morphine (0.08mg/kg) or pentazocine (0.5mg/kg) compared to saline placebo. Both active drug and placebo were administered once during the follicular phase and once during the luteal phase. Measures of heat, ischemic, and pressure pain sensitivity were obtained before and after drug administration. Change scores in pain responses were computed to determine morphine and pentazocine analgesic responses, and medication side effects were recorded. The data were analyzed using mixed-model analyses of variance. NOC women showed slightly greater heat pain sensitivity in the follicular vs luteal phase, while the reverse pattern emerged for OC women (P=0.046). Also, OC women showed lower pressure pain thresholds compared to NOC women (P<0.05). Regarding analgesic responses, NOC women showed greater morphine analgesia for ischemic pain during the follicular vs the luteal phase (P=0.004). Likewise, side effects for morphine were significantly higher in NOC women in the follicular phase than in the luteal phase (P=0.02). These findings suggest that sex hormones may influence opioid responses; however, the effects vary across medications and pain modalities and are likely to be modest in magnitude. Limited menstrual cycle effects on baseline pain responses were observed; however, morphine analgesia and side effects were greater during the follicular phase.


Assuntos
Analgésicos Opioides/uso terapêutico , Hiperalgesia/tratamento farmacológico , Ciclo Menstrual/efeitos dos fármacos , Morfina/uso terapêutico , Limiar da Dor/efeitos dos fármacos , Pentazocina/uso terapêutico , Adolescente , Adulto , Feminino , Hormônios Esteroides Gonadais/sangue , Humanos , Hiperalgesia/fisiopatologia , Medição da Dor/métodos , Estatística como Assunto , Adulto Jovem
5.
EMBO J ; 26(7): 1902-12, 2007 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-17363903

RESUMO

The regulation of myogenic progenitor cells during muscle regeneration is not clearly understood. We have previously shown that the Foxk1 gene, a member of the forkhead/winged helix family of transcription factors, is expressed in myogenic progenitor cells in adult skeletal muscle. In the present study, we utilize transgenic technology and demonstrate that the 4.6 kb upstream fragment of the Foxk1 gene directs beta-galactosidase expression to the myogenic progenitor cell population. We further establish that Sox15 directs Foxk1 expression to the myogenic progenitor cell population, as it binds to an evolutionarily conserved site and recruits Fhl3 to transcriptionally coactivate Foxk1 gene expression. Knockdown of endogenous Sox15 results in perturbed cell cycle kinetics and decreased Foxk1 expression. Furthermore, Sox15 mutant mice display perturbed skeletal muscle regeneration, due in part to decreased numbers of satellite cells and decreased Foxk1 expression. These studies demonstrate that Sox15, Fhl3 and Foxk1 function to coordinately regulate the myogenic progenitor cell population and skeletal muscle regeneration.


Assuntos
Fatores de Transcrição Forkhead/metabolismo , Proteínas de Grupo de Alta Mobilidade/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Músculo Esquelético/citologia , Células-Tronco/citologia , Fatores de Transcrição/metabolismo , Transcrição Gênica , Animais , Sequência de Bases , Sítios de Ligação , Ciclo Celular , Sequência Conservada , Embrião de Mamíferos/metabolismo , Fatores de Transcrição Forkhead/genética , Regulação da Expressão Gênica , Proteínas de Grupo de Alta Mobilidade/química , Peptídeos e Proteínas de Sinalização Intracelular/química , Cinética , Proteínas com Domínio LIM , Camundongos , Camundongos Knockout , Dados de Sequência Molecular , Músculo Esquelético/fisiologia , Mutagênese , Regiões Promotoras Genéticas/genética , Ligação Proteica , Estrutura Terciária de Proteína , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Regeneração , Fatores de Transcrição SOX , Células-Tronco/metabolismo , Fatores de Transcrição/química
6.
Mol Pharmacol ; 71(3): 884-92, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17167030

RESUMO

Valproic acid (VPA) is an effective antiepileptic drug with an additional activity for the treatment of bipolar disorder. It has been assumed that both activities arise from a common target. At the molecular level, VPA targets a number of distinct proteins that are involved in signal transduction. VPA inhibition of inositol synthase reduces the cellular concentration of myo-inositol, an effect common to the mood stabilizers lithium and carbamazepine. VPA inhibition of histone deacetylases activates Wnt signaling via elevated beta-catenin expression and causes teratogenicity. Given the VPA chemical structure, it may be possible to design VPA derivatives and analogs that modulate specific protein targets but leave the others unaffected. Indeed, it has been shown that some nonteratogenic VPA derivatives retain antiepileptic and inositol signaling effects. In this study, we describe a further set of VPA analogs and derivatives that separate anticonvulsant activity from effects on neuronal growth cone morphology. Lithium, carbamazepine, and VPA induce inositol-dependent spread of neuronal growth cones, providing a cell-based assay that correlates with mood-stabilizing activity. We find that two constitutional isomers of VPA, propylisopropylacetic acid and diisopropylacetic acid, but not their corresponding amides, and N-methyl-2,2,3,3-tetramethyl-cyclopropanecarboaxamide are more effective than VPA in increasing growth cone spreading. We show that these effects are associated with inositol depletion, and not changes in beta-catenin-mediated Wnt signaling. These results suggest a route to a new generation of central nervous system-active VPA analogs that specifically target bipolar disorder.


Assuntos
Anticonvulsivantes/farmacologia , Cones de Crescimento/efeitos dos fármacos , Ácido Valproico/análogos & derivados , Ácido Valproico/farmacologia , Animais , Células Cultivadas , Dictyostelium/efeitos dos fármacos , Gânglios Espinais/efeitos dos fármacos , Cones de Crescimento/fisiologia , Inositol 1,4,5-Trifosfato/análise , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Proteínas Wnt/fisiologia
7.
Opt Express ; 15(22): 14711-6, 2007 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-19550752

RESUMO

The field enhancement in the gap between two Si microdisks is theoretically investigated using the finite difference time domain method. We show that the electric field within this gap increases as the distance between the two disks decreases, and it can be enhanced by as much as two orders of magnitude. By perturbing the Si microdisks to force the field leakage into an ever smaller volume, the field enhancement can reach a value as high as 238 with a deep sub-wavelength mode volume. This behavior is comparable to what can be observed in gap plasmons between metal nanoparticles, but is produced here in purely dielectric structures.

8.
Br J Plast Surg ; 58(2): 158-9, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15710108

RESUMO

By mobilisation of the jejunal marginal artery with reverse flow, the authors present a novel way of increasing artery length available for anastomosis in free jejunal loop transfer for reconstruction in head and neck cancer surgery.


Assuntos
Neoplasias de Cabeça e Pescoço/cirurgia , Jejuno/transplante , Retalhos Cirúrgicos/irrigação sanguínea , Anastomose Cirúrgica , Artérias , Humanos , Jejuno/irrigação sanguínea
9.
Mol Pharmacol ; 67(5): 1426-33, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15687223

RESUMO

Inositol-1,4,5-trisphosphate (InsP3) depletion has been implicated in the therapeutic action of bipolar disorder drugs, including valproic acid (VPA). It is not currently known whether the effect of VPA on InsP3 depletion is related to the deleterious effects of teratogenicity or elevated viral replication, or if it occurs via putative inhibitory effects on glycogen synthase kinase-3beta (GSK-3beta). In addition, the structural requirements of VPA-related compounds to cause InsP3 depletion are unknown. In the current study, we selected a set of 10 VPA congeners to examine their effects on InsP3 depletion, in vivo teratogenic potency, HIV replication, and GSK-3beta activity in vitro. We found four compounds that function to deplete InsP3 in the model eukaryote Dictyostelium discoideum, and these drugs all cause growth-cone enlargement in mammalian primary neurons, consistent with the effect of InsP3 depletion. No relationship was found between InsP3 depletion and teratogenic or elevated viral replication effects, and none of the VPA congeners were found to affect GSK-3beta activity. Structural requirements of VPA congers to maintain InsP3 depletion efficacy greater than that of lithium are a carboxylic-acid function without dependence on side-chain length, branching, or saturation. Noteworthy is the enantiomeric differentiation if a chiral center exists, suggesting that InsP3 depletion is mediated by a stereoselective mode of action. Thus, the effect of InsP3 depletion can be separated from that of teratogenic potency and elevated viral replication effect. We have used this to identify two VPA derivatives that share the common InsP3-depleting action of VPA, lithium and carbamazepine, but do not show the side effects of VPA, thus providing promising novel candidates for bipolar disorder treatment.


Assuntos
Transtorno Bipolar/tratamento farmacológico , Quinase 3 da Glicogênio Sintase/antagonistas & inibidores , Inositol 1,4,5-Trifosfato/metabolismo , Ácido Valproico/análogos & derivados , Ácido Valproico/farmacologia , Replicação Viral/efeitos dos fármacos , Animais , Linhagem Celular , Avaliação Pré-Clínica de Medicamentos/métodos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , HIV-1/efeitos dos fármacos , HIV-1/fisiologia , Humanos , Ratos , Teratogênicos/farmacologia , Ácido Valproico/uso terapêutico , Replicação Viral/fisiologia
10.
Hum Reprod ; 19(12): 2816-21, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15375077

RESUMO

We report on dizygotic (DZ) twins, conceived by IVF and ICSI with assisted hatching, who each had a mixture of 46,XX and 46,XY cells in blood lymphocytes. The female twin had mild genitalia abnormalities but further study revealed anatomically normal reproductive anatomy. Chromosome and fluorescence in situ hybridization studies of buccal, skin and ovarian tissue were normal, as were buccal tissue DNA studies. Fetal ultrasound and fetal membrane pathology were consistent with a monochorionic, diamniotic placenta (MCDAP). These twins thus have blood chimerism but are not chimeric in the other tissues studied. The mechanism for the chimerism could be due to either placental vascular anastamoses (after the development of the haematoblast stem cells) or due to an admixture of trophoblast cells during early blastocyst development. Such trophoblast cell admixtures would be restricted to the extraembryonic tissues so that general physical development in the fetus is normal and without somatic cell chimerism. This case in combination with others previously reported suggests that in IVF conceptions, the prevalence of blood chimerism associated with twinning, and the occurrence of DZ twinning associated with MCDAP, may be higher than previously thought.


Assuntos
Quimera , Fertilização in vitro , Linfócitos/fisiologia , Gêmeos Dizigóticos/genética , Adulto , Córion , Doenças em Gêmeos/genética , Sistema Endócrino/metabolismo , Feminino , Fibroblastos/fisiologia , Genitália/anormalidades , Humanos , Hibridização in Situ Fluorescente , Lactente , Recém-Nascido , Masculino , Repetições de Microssatélites , Mosaicismo , Ovário/anormalidades , Gravidez , Pele/citologia , Ultrassonografia Pré-Natal
12.
Clin Otolaryngol Allied Sci ; 29(2): 175-8, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15113306

RESUMO

Several nasendoscopic techniques have been described to improve the view of different anatomical subsites when assessing the laryngopharynx. A prospective study was undertaken to compare and evaluate the views obtained with each of the different techniques employed in the nasendoscopic examination of the upper aero-digestive tract. No visualization manoeuvres were found to be beneficial in improving the view of the tongue base; however, tongue protrusion did improve the view of the valleculae. Both the post-cricoid and the upper oesophageal sphincter were best seen when the trumpet manoeuvre was performed along with skin traction of the anterior neck. Pyriform apices were best viewed when the trumpet manoeuvre was coupled with head turn - a manoeuvre we believe not to have been recorded in the literature previously with respect to this topic. The authors present a systematic routine for examining the upper aero-digestive tract by nasendoscope on the basis of obtaining the best view for each anatomical subsite.


Assuntos
Laringoscopia/métodos , Laringe/anatomia & histologia , Faringe/anatomia & histologia , Movimentos da Cabeça , Humanos , Mandíbula , Cavidade Nasal/cirurgia , Valores de Referência , Língua , Tração , Manobra de Valsalva
13.
J Neurol Neurosurg Psychiatry ; 74(12): 1680-4, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14638889

RESUMO

OBJECTIVES: To evaluate the results of treatment of patients with a ruptured intracranial aneurysm treated by a single experienced vascular neurosurgeon in the period prior to the introduction of endovascular coiling. METHODS: Over a mean (SD) period of 9 (2) years, between January 1990 and June 1999, 245 consecutive patients with ruptured intracranial aneurysms were treated. Patients' details were obtained from a database that had been constructed prospectively. The patients consisted of all those patients treated by the senior author (Mr Maurice-Williams) over this period-that is, every third day on call at his unit. During this period, all patients under the age of 75 years with a diagnosis of subarachnoid haemorrhage were admitted to the neurosurgical unit as soon as was practicable regardless of clinical grade. RESULTS: Of 245 patients, 190 (77.6%) underwent treatment by open surgery using standard microsurgical techniques. At 1 year, the mortality of the operated patients was 2.6%, while 89.5% of the patients had a Glasgow Outcome Score (GOS) of 4 and 5. The overall management outcome (all patients treated, including operated and non-operated cases) at 1 year was: 17.1 % dead while 74.3% had GOS 4 and 5. Of the 190 patients who underwent surgery, 38 (20%) required additional operations, totalling 72 operations in all. Of these, 32 were for hydrocephalus and 17 for the evacuation of intracranial haematomas/collections. Complications of surgery occurred in 56 patients (29.5%). CONCLUSION: Open surgery, despite good eventual results, is associated with a significant rate of re-operations and complications that would probably be largely avoided with endovascular treatment. Nevertheless, although endovascular coiling has these immediate advantages over surgery it is still not certain that the long term results will be superior to surgery which leads to permanent obliteration of the aneurysm. There may still be a need for open surgery in the future.


Assuntos
Aneurisma Roto/cirurgia , Revascularização Cerebral/efeitos adversos , Competência Clínica , Aneurisma Intracraniano/cirurgia , Procedimentos Neurocirúrgicos/efeitos adversos , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
15.
Clin Otolaryngol Allied Sci ; 28(4): 331-4, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12871247

RESUMO

Patients receiving Gentisone HC, Sofradex and Otomize for chronic suppurative otitis media and otitis externa were investigated for compliance of medication. Drops were accurately weighed before and after use so that both the amount used and the expected amount patients should have used could be calculated. The amount used differed statistically from the amount expected for Sofradex (P = 0.0008) but not for Gentisone HC (P = 0.1049) or Otomize (P = 0.7553) when analysed by a Mann-Whitney U-test. There was a trend to overdose with both Sofradex & Gentisone HC. The reason for the differences, we believe, is due to a combination of both differing delivery systems and drop viscosities. Manufacturers need to improve delivery systems so that patients can deliver a reproducible volume of medication each time with ease.


Assuntos
Dexametasona/administração & dosagem , Framicetina/administração & dosagem , Gentamicinas/administração & dosagem , Gramicidina/administração & dosagem , Hidrocortisona/administração & dosagem , Neomicina/administração & dosagem , Otite Externa/tratamento farmacológico , Otite Média Supurativa/tratamento farmacológico , Cooperação do Paciente , Administração Tópica , Doença Crônica , Combinação de Medicamentos , Humanos , Estatísticas não Paramétricas
17.
Rhinology ; 41(1): 56-7, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12677743

RESUMO

An unusual case of an oropharyngeal mass in a neonate causing intermittent airway obstruction during the first 24 hours following delivery is presented. This mass was confirmed to be a hairy polyp. We discuss the incidence, histology and peri-operative management of this unusual lesion.


Assuntos
Neoplasias Orofaríngeas/diagnóstico , Teratoma/diagnóstico , Obstrução das Vias Respiratórias/etiologia , Humanos , Recém-Nascido , Masculino , Neoplasias Orofaríngeas/patologia , Neoplasias Orofaríngeas/cirurgia , Teratoma/patologia , Teratoma/cirurgia
18.
Proc Natl Acad Sci U S A ; 100(2): 669-74, 2003 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-12515860

RESUMO

The calcium/calmodulin-dependent protein phosphatase calcineurin stimulates cardiac hypertrophy in response to numerous stimuli. Calcineurin activity is suppressed by association with modulatory calcineurin-interacting protein (MCIP)1DSCR1, which is up-regulated by calcineurin signaling and has been proposed to function in a negative feedback loop to modulate calcineurin activity. To investigate the involvement of MCIP1 in cardiac hypertrophy in vivo, we generated MCIP1 null mice and subjected them to a variety of stress stimuli that induce cardiac hypertrophy. In the absence of stress, MCIP1(-/-) animals exhibited no overt phenotype. However, the lack of MCIP1 exacerbated the hypertrophic response to activated calcineurin expressed from a muscle-specific transgene, consistent with a role of MCIP1 as a negative regulator of calcineurin signaling. Paradoxically, however, cardiac hypertrophy in response to pressure overload or chronic adrenergic stimulation was blunted in MCIP1(-/-) mice. These findings suggest that MCIP1 can facilitate or suppress cardiac calcineurin signaling depending on the nature of the hypertrophic stimulus. These opposing roles of MCIP have important implications for therapeutic strategies to regulate cardiac hypertrophy through modulation of calcineurin-MCIP activity.


Assuntos
Cardiomegalia/etiologia , Proteínas Musculares/fisiologia , Animais , Calcineurina/análise , Calcineurina/fisiologia , Proteínas de Ligação a DNA , Peptídeos e Proteínas de Sinalização Intracelular , Masculino , Camundongos , Camundongos Knockout
19.
Mol Hum Reprod ; 8(12): 1071-8, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12468639

RESUMO

The objective of this study was to elucidate the biological significance of GnRH and antiprogestins and antiestrogen in leiomyoma and their interactions with ovarian steroid 'add-back' therapy. Leiomyoma and myometrial smooth muscle cells (LSMC and MSMC) were isolated and exposed to GnRH agonist (leuprolide acetate, LA), 17beta-estradiol (E2), medroxyprogesterone acetate (MPA), GnRH antagonist (Antide), estrogen antagonist, ICI182780 (Fulvestrant) and progesterone antagonists RU486 (Mifepristone) and ZK98299 (Onapristone) and combinations thereof. The rate of DNA synthesis, cell proliferation and transforming growth factor-beta (TGF-beta) expression were then determined. In both cell types, we found that in a dose-dependent manner, LA inhibited, whereas E2, MPA and the combination of E2 + MPA stimulated, the rate of DNA synthesis in these cells. Antide reversed the inhibitory effect of LA, while LA partly inhibited the stimulatory effect of the steroids. In addition, RU486, ICI182780 and ZK98299 at 0.1 micro mol/l or higher doses inhibited the rate of DNA synthesis and partly reversed the effects of E2 and/or MPA. We also found that LSMC expressed elevated levels of TGF-beta1 compared with MSMC. In both cell types, the effects of LA, E2, MPA, RU, ZK and ICI and combinations thereof on TGF-beta1 production were reflective of their effects on DNA synthesis. In line with this, TGF-beta1 was found to stimulate DNA synthesis and the E2-, TGF-beta1- or E2 + TGF-beta1-induced DNA synthesis was found to be inhibited by TGF-beta1 neutralizing antibodies and/or LA. In conclusion, the results provide further evidence that GnRH agonist- and RU486-induced leiomyoma regression is mediated in part through an interactive mechanism that results in altered cell growth and suppression of TGF-beta production.


Assuntos
Moduladores de Receptor Estrogênico/farmacologia , Hormônio Liberador de Gonadotropina/análogos & derivados , Leiomioma/tratamento farmacológico , Progestinas/antagonistas & inibidores , Esteroides/farmacologia , Estradiol/farmacologia , Feminino , Hormônio Liberador de Gonadotropina/agonistas , Gonanos/farmacologia , Humanos , Leuprolida/farmacologia , Acetato de Medroxiprogesterona/farmacologia , Mifepristona/farmacologia , Desenvolvimento Muscular/efeitos dos fármacos , Desenvolvimento Muscular/fisiologia , Miócitos de Músculo Liso/metabolismo , Miométrio/efeitos dos fármacos , Miométrio/crescimento & desenvolvimento , Oligopeptídeos/farmacologia , Fatores de Crescimento Transformadores/biossíntese , Fatores de Crescimento Transformadores/efeitos dos fármacos , Fatores de Crescimento Transformadores/genética
20.
Clin Radiol ; 57(8): 725-9, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12169283

RESUMO

AIM: Although the National Health Service (NHS) Breast Screening Programme is aimed at asymptomatic women, inevitably patients attending screening report symptoms. The study aim was to assess the usefulness of recall based on clinical symptoms. MATERIALS AND METHODS: Information on breast symptoms is recorded at screening and radiologists can make recall decisions based on mammography and symptom history. We identified 1394 women with significant symptoms, between 1991 and 1996. The majority (54%) complained of a lump, 21% had breast distortion, 18% breast pain alone and 6% reported nipple discharge. RESULTS: Of the 1394 women, 262 were recalled because of mammographic suspicion and of these, 45% had breast cancer. The other 1132 women had symptoms and benign mammograms and 44% of these were recalled. Seven breast cancers were diagnosed; all had complained of a breast lump. In two the cancer would have been seen on two-view mammography. Of 638 not recalled, five women went on to develop an interval cancer. CONCLUSION: The results indicate that collecting details on symptoms is useful given the high rate of breast cancer in those with mammographic abnormality. When mammography is benign, however, the low rate of cancer detection means recall should be selective based on only the most relevant symptoms.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Programas de Rastreamento , Neoplasias da Mama/diagnóstico , Exsudatos e Transudatos , Feminino , Humanos , Mamografia , Anamnese , Pessoa de Meia-Idade , Dor/etiologia , País de Gales
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