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1.
Clin Exp Immunol ; 202(3): 335-352, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32734627

RESUMO

The aim of this study was to investigate the pathogenesis of combination ipilimumab and nivolumab-associated colitis (IN-COL) by measuring gut-derived and peripheral blood mononuclear cell (GMNC; PBMC) profiles. We studied GMNC and PBMC from patients with IN-COL, IN-treated with no adverse-events (IN-NAE), ulcerative colitis (UC) and healthy volunteers using flow cytometry. In the gastrointestinal-derived cells we found high levels of activated CD8+ T cells and mucosal-associated invariant T (MAIT) cells in IN-COL, changes that were not evident in IN-NAE or UC. UC, but not IN-C, was associated with a high proportion of regulatory T cells (Treg ). We sought to determine if local tissue responses could be measured in peripheral blood. Peripherally, checkpoint inhibition instigated a rise in activated memory CD4+ and CD8+ T cells, regardless of colitis. Low circulating MAIT cells at baseline was associated with IN-COL patients compared with IN-NAE in one of two cohorts. UC, but not IN-COL, was associated with high levels of circulating plasmablasts. In summary, the alterations in T cell subsets measured in IN-COL-affected tissue, characterized by high levels of activated CD8+ T cells and MAIT cells and a low proportion of Treg , reflected a pathology distinct from UC. These tissue changes differed from the periphery, where T cell activation was a widespread on-treatment effect, and circulating MAIT cell count was low but not reliably predictive of colitis.


Assuntos
Linfócitos T CD8-Positivos , Colite , Mucosa Intestinal , Ipilimumab/efeitos adversos , Células T Invariantes Associadas à Mucosa , Nivolumabe/efeitos adversos , Linfócitos T Reguladores , Adulto , Idoso , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Colite/induzido quimicamente , Colite/imunologia , Colite/patologia , Feminino , Citometria de Fluxo , Humanos , Mucosa Intestinal/imunologia , Mucosa Intestinal/patologia , Ipilimumab/administração & dosagem , Masculino , Pessoa de Meia-Idade , Células T Invariantes Associadas à Mucosa/imunologia , Células T Invariantes Associadas à Mucosa/patologia , Nivolumabe/administração & dosagem , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/patologia
2.
Nutr Cancer ; 69(7): 996-1002, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28945110

RESUMO

Obesity is associated with a greater risk of prostate cancer mortality. However, the mechanisms connecting obesity to the progression of prostate cancer remain unknown. This study determined the impact of obesity on macrophage recruitment and tumor-associated macrophage (TAM) polarization in the prostate tumor microenvironment, since a high concentration of TAMs in tumors has been linked to progression in prostate cancer. We utilized an in vitro model in which pre-adipocytes, prostate cancer cells, and macrophages were exposed to sera from obese or nonobese men, or conditioned media generated under obese or nonobese conditions. Matrigel invasion chambers were used to assess macrophage recruitment in vitro, and immunohistochemical analysis evaluated recruitment in a PTEN knockout mouse model. qPCR was used to measure mRNA levels of CCL2, COX-2, IL-10, TGF-beta, VEGF-A, arginase-1, and MMP-9. PGE2 production was measured by ELISA. Obesity increased macrophage and TAM recruitment, and increased mRNA levels of TAM markers in macrophages. Similarly, obese conditions increased CCL2 and COX-2 expression, as well as PGE2 levels in prostate cancer cells. COX-2 inhibition resulted in lower expression of obesity-induced TAM markers. Our data suggest that obesity promotes macrophage infiltration into the prostate tumor microenvironment, and induces TAM polarization through the COX-2/PGE2 pathway.


Assuntos
Macrófagos/patologia , Obesidade/complicações , Neoplasias da Próstata/patologia , Microambiente Tumoral , Animais , Linhagem Celular Tumoral , Quimiocina CCL2/genética , Ciclo-Oxigenase 2/genética , Dinoprostona/metabolismo , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Humanos , Macrófagos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Obesos , Obesidade/patologia , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Comunicação Parácrina , Neoplasias da Próstata/metabolismo
3.
J Fr Ophtalmol ; 46(2): 123-128, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36564303

RESUMO

OBJECTIVE: To evaluate the safety and efficacy of the Xen® implant for the treatment of open-angle glaucoma. MATERIAL AND METHOD: Retrospective study including patients who received the Xen® implant between January 2019 and December 2020 in a university hospital. Demographic and medical data were collected using DxCare® software. The primary endpoint was a 20% reduction in intraocular pressure (IOP) at 12 months according to Société Française du Glaucome (SFG) recommendations. The secondary endpoints were decrease in glaucoma medications and incidence of adverse events. RESULTS: Fifty-three patients (65 eyes) were included (sex ratio 0.65, age 75.38±7.31 years). IOP decreased by 18.51% from 17.86±4.22mmHg to 14.55±2.66mmHg (P<0.05). The number of glaucoma medications was 2.16±1.01 preoperatively vs 0.49±0.94 postoperatively (P<0.05). Adverse events included 8 malpositionings, 3 of which required reoperation, 1 case of increased IOP resolved by trabeculectomy, 1 case of venous ischemia treated by photocoagulation, 3 choroidal detachments and 3 corneal ulcers. Needling was required for 18 eyes. CONCLUSION: At 12 months, the IOP was lower than previously reported in the literature (14.55 vs 15.90mmHg, P<0.05), probably due to a lower preoperative IOP. The number of postoperative medications was similar to the literature (0.49 vs 0.40, P=0.51), as was the frequency of needling (27.69% vs 32.00%, P=0.36). The frequency of malpositioning was higher (12.31% vs 7.70%, P<0.05), probably due to the management of complicated patients. The efficacy of Xen® was in line with recommendations. It would be interesting to compare the efficacy of Xen® with trabeculectomy.


Assuntos
Implantes para Drenagem de Glaucoma , Glaucoma de Ângulo Aberto , Glaucoma , Trabeculectomia , Idoso , Idoso de 80 Anos ou mais , Humanos , Gelatina , Glaucoma/cirurgia , Implantes para Drenagem de Glaucoma/efeitos adversos , Glaucoma de Ângulo Aberto/epidemiologia , Glaucoma de Ângulo Aberto/cirurgia , Pressão Intraocular , Estudos Retrospectivos , Resultado do Tratamento
4.
J Neurosci Methods ; 394: 109900, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37295749

RESUMO

BACKGROUND: Writing and drawing orientation is rarely assessed in clinical routine, although it might have a potential value in detecting impaired verticality perception after right hemispheric stroke (RHS). Assessment tools and criteria must be conceived and validated. We therefore explored the clinimetric properties of a set of quantitative writing and drawing orientation criteria, their ranges of normality, and their tilt prevalence in RHS individuals. NEW METHODS: We asked 69 individuals with subacute RHS and 64 matched healthy controls to write three lines and to copy the Gainotti Figure (house and trees). We determined six criteria referring to the orientation of writing and drawing main axes: for writing, the line and margin orientations, and for drawing, the tree, groundline, wall, and roofline orientations. Orientations were measured by using an electronic protractor from specific landmarks positioned by independent evaluators. RESULTS: The set of criteria fulfilling all clinimetric properties (feasibility, measurability, reliability) comprised the line orientation of the writing and the wall and roofline orientations of the drawing. Writing and drawing tilts were frequent after RHS (about 30% by criterion). COMPARISON WITH EXISTING METHODS: So far, graphomotor orientation was mostly tested qualitatively and could not be objectively appreciated in absence of validated tools and criteria, and without ranges of normality. Writing and drawing tilts may now be assessed both in routine clinical practice and research. CONCLUSIONS: Our study paves the way for investigating the clinical determinants of graphomotor tilts, including impaired verticality perception, to better understand their underlying mechanisms.


Assuntos
Acidente Vascular Cerebral , Humanos , Reprodutibilidade dos Testes , Percepção Espacial , Redação
5.
Am J Primatol ; 73(3): 291-303, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21274900

RESUMO

The ranges of small kinda (Papio kindae) and much larger grayfooted chacma (P. ursinus griseipes) baboons adjoin in the Kafue National Park, Zambia. In a visual survey of baboons at 48 sites in the Kafue River drainage we found that, contrary to previous reports, groups at the species interface near the town of Ngoma are phenotypically diverse and presumably formed by multigenerational hybridization. Mitochondrial and/or Y-chromosome genetic markers from fecal samples (N=164) collected at 29 sites support this conclusion. Groups with phenotypic signs of a history of hybridization also had taxon-specific mitochondria and Y-haplotypes from both parental species. Although the distribution of mitochondrial haplotypes largely mirrored that of external phenotypes, a significant proportion of male specimens from grayfoot as well as hybrid groups carried kinda Y-chromosomes, and kinda Y-chromosomes were involved in all observed cases of mitochondrial/Y-chromosome discordance. These observations are consistent with, though they do not prove, a population history in which the range of chacmas and the hybrid zone have advanced at the expense of the kinda range. They also suggest that, unexpectedly, kinda male×chacma female matings are much more common than the reciprocal cross in the ancestry of hybrids. We suggest that distinctive male kinda behavior and the "juvenile" appearance of kinda baboons of both sexes, perhaps combined with obstetric difficulties of a small kinda female carrying the large offspring of a chacma male, may account for this bias.


Assuntos
Hibridização Genética , Papio/genética , Animais , Animais Selvagens/anatomia & histologia , Animais Selvagens/genética , DNA Mitocondrial/genética , DNA Mitocondrial/isolamento & purificação , Feminino , Genes Ligados ao Cromossomo Y/genética , Marcadores Genéticos , Variação Genética , Haplótipos , Masculino , Papio/anatomia & histologia , Papio ursinus/anatomia & histologia , Papio ursinus/genética , Fenótipo , Comportamento Sexual Animal , Zâmbia
6.
Sci Rep ; 11(1): 19253, 2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34584157

RESUMO

Development of anti-drug antibodies (ADAs) can interfere with therapeutic monoclonal antibodies and may lead to drug neutralisation and clinical disease progression. Measurement of circulating drug levels and development of ADAs in the setting of anti-programmed cell death-1 agent pembrolizumab has not been well-studied. Enzyme-linked immunosorbent assays were used to measure pembrolizumab drug level and ADAs in 41 patients with melanoma at baseline, Time-point 1 (3 weeks) and Time-point 2 (21 weeks). Assay results were related to patient demographics and clinical outcome data at 6 months. The median pembrolizumab drug level at 3 weeks was 237 ng/µL and did not correlate with age, sex or body surface area.17/41 patients had an ADA detected at any timepoint, with the highest prevalence at Timepoint 1 (median concentration = 17 ng/µL). The presence of an ADA did not correlate with clinical progression at 6 months. 3/41 (7%) of patients displayed a falling pembrolizumab drug level and rising ADA titre between Timepoint 1 and 2 suggestive of a neutralising ADA. Pembrolizumab drug levels and ADAs can be readily measured. The rates of total and treatment-emergent ADAs may be higher in "real-word" settings than those previously reported. Larger studies are needed to determine effect of neutralising ADAs on long-term clinical outcome.


Assuntos
Anticorpos Monoclonais Humanizados/imunologia , Anticorpos Neutralizantes/sangue , Antineoplásicos Imunológicos/imunologia , Melanoma/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/farmacocinética , Antineoplásicos Imunológicos/administração & dosagem , Antineoplásicos Imunológicos/farmacocinética , Progressão da Doença , Monitoramento de Medicamentos , Feminino , Humanos , Masculino , Melanoma/sangue , Melanoma/imunologia , Neoplasias Cutâneas/sangue , Neoplasias Cutâneas/imunologia , Resultado do Tratamento
7.
J Urol ; 184(3): 1116-21, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20650478

RESUMO

PURPOSE: We present the results of a new technique using a pedicled cutaneous flap for continent cystostomy. MATERIALS AND METHODS: A total of 15 boys and 8 girls (mean +/- SD age 13.4 +/- 6.4 years) underwent continent cystostomy for neurogenic bladder (20), bladder exstrophy (2) and sequelae of hypospadias (1) between 1999 and 2008. In this procedure a rectangular pedicled flap is surgically elevated from a hairless area on the abdomen. The flap is tubularized and passed through the anterior abdominal wall directly into the bladder. A submucosal detrusor incision is made to expose the bladder mucosa, and the distal part of the flap is anastomosed to the bladder mucosa in a circular manner. The tube is positioned along the incised detrusor, which is closed over. Viability of the flap, self-catheterization management and continence status are then evaluated. RESULTS: Mean +/- SD followup was 4.5 +/- 3.1 years. There was 1 case of distal necrosis of the flap, which required a secondary surgery using the Mitrofanoff technique. The 22 remaining flaps were initially viable, although 2 patients were eventually lost to followup and 3 subsequently presented with false-passage incidents requiring a few days of calibration using a balloon catheter. Dryness was achieved immediately in 73% of the cases. After adding a complementary bulking agent the dryness rate reached 77%. CONCLUSIONS: We present a novel approach to continent cystostomy that is safe and easy to perform. This technique is a less invasive and more efficient alternative to other commonly used approaches.


Assuntos
Cistostomia/métodos , Retalhos Cirúrgicos , Bexiga Urinaria Neurogênica/cirurgia , Coletores de Urina , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino
8.
J Cell Biol ; 145(6): 1133-43, 1999 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-10366587

RESUMO

The cell nucleus is organized as discrete domains, often associated with specific events involved in chromosome organization, replication, and gene expression. We have examined the spatial and functional relationship between the sites of heat shock gene transcription and the speckles enriched in splicing factors in primary human fibroblasts by combining immunofluorescence and fluorescence in situ hybridization (FISH). The hsp90alpha and hsp70 genes are inducibly regulated by exposure to stress from a low basal level to a high rate of transcription; additionally the hsp90alpha gene contains 10 introns whereas the hsp70 gene is intronless. At 37 degrees C, only 30% of hsp90alpha transcription sites are associated with speckles whereas little association is detected with the hsp70 gene, whose constitutive expression is undetectable relative to the hsp90alpha gene. Upon exposure of cells to heat shock, the heavy metal cadmium, or the amino acid analogue azetidine, transcription at the hsp90alpha and hsp70 gene loci is strongly induced, and both hsp transcription sites become associated with speckles in >90% of the cells. These results reveal a clear disconnection between the presence of intervening sequences at specific gene loci and the association with splicing factor-rich regions and suggest that subnuclear structures containing splicing factors are associated with sites of transcription.


Assuntos
Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP90/genética , Íntrons/genética , Proteínas Nucleares/metabolismo , Ribonucleoproteínas , Spliceossomos/metabolismo , Transcrição Gênica/genética , Azetidinas/farmacologia , Cádmio/farmacologia , Células Cultivadas , Fibroblastos , Imunofluorescência , Resposta ao Choque Térmico/genética , Humanos , Hibridização in Situ Fluorescente , RNA Polimerase II/metabolismo , Splicing de RNA/efeitos dos fármacos , Splicing de RNA/genética , RNA Mensageiro/análise , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ribonucleoproteínas Nucleares Pequenas/metabolismo , Fatores de Processamento de Serina-Arginina , Spliceossomos/efeitos dos fármacos , Spliceossomos/genética , Temperatura , Transcrição Gênica/efeitos dos fármacos , Ativação Transcricional
9.
Risk Anal ; 29(10): 1395-409, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19659555

RESUMO

This study evaluates farmers' beliefs and perceived risks of aflatoxin (AF) on the consumption, production, and marketing of groundnuts. A survey was conducted with 181 farmers in Benin to assess their beliefs of AF effects on the marketing of groundnuts, and finally human and animal health. Awareness and action factors were also evaluated. Relationships of the belief and action factors with socioeconomic variables were evaluated using multiple indicators and multiple causes (MIMIC) models within a socioeconomic framework using a health belief model (HBM). The results indicate that the scale of the various constructs is reliable and the validity conforms to expectations. The unifactorial models developed in this study provide a satisfactory fit with NFl, CFI, and GFI exceeding 0.90. The results reveal that gender, age, and years of experience in farming significantly impact farmers' action regarding the reduction of AF in groundnut production and marketing. Male farmers are more likely to be aware of AF problems in groundnuts and feel more susceptible to the problems than their female counterparts. Gender and education seem to be dominating factors in the perception of barriers to mitigating the effects of AF, and male and older farmers are more likely to perceive the benefits of producing and marketing good quality groundnuts.


Assuntos
Aflatoxinas/toxicidade , Nozes/química , Fatores Socioeconômicos , Aflatoxinas/análise , Agricultura , Benin , Feminino , História do Século XVI , Humanos , Masculino , Pessoa de Meia-Idade
10.
Mol Cell Biol ; 21(21): 7163-71, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11585899

RESUMO

Vertebrate cells express a family of heat shock transcription factors (HSF1 to HSF4) that coordinate the inducible regulation of heat shock genes in response to diverse signals. HSF1 is potent and activated rapidly though transiently by heat shock, whereas HSF2 is a less active transcriptional regulator but can retain its DNA binding properties for extended periods. Consequently, the differential activation of HSF1 and HSF2 by various stresses may be critical for cells to survive repeated and diverse stress challenges and to provide a mechanism for more precise regulation of heat shock gene expression. Here we show, using a novel DNA binding and detection assay, that HSF1 and HSF2 are coactivated to different levels in response to a range of conditions that cause cell stress. Above a low basal activity of both HSFs, heat shock preferentially activates HSF1, whereas the amino acid analogue azetidine or the proteasome inhibitor MG132 coactivates both HSFs to different levels and hemin preferentially induces HSF2. Unexpectedly, we also found that heat shock has dramatic adverse effects on HSF2 that lead to its reversible inactivation coincident with relocalization from the nucleus. The reversible inactivation of HSF2 is specific to heat shock and does not occur with other stressors or in cells expressing high levels of heat shock proteins. These results reveal that HSF2 activity is negatively regulated by heat and suggest a role for heat shock proteins in the positive regulation of HSF2.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/fisiologia , Proteínas de Choque Térmico/metabolismo , Proteínas de Choque Térmico/fisiologia , Fatores de Transcrição/metabolismo , Fatores de Transcrição/fisiologia , Células 3T3 , Animais , Western Blotting , Núcleo Celular/metabolismo , Citoplasma/metabolismo , DNA/metabolismo , Ativação Enzimática , Fatores de Transcrição de Choque Térmico , Camundongos , Microscopia de Fluorescência , Modelos Biológicos , Ligação Proteica , Transcrição Gênica
11.
J Basic Clin Physiol Pharmacol ; 18(4): 289-98, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18380170

RESUMO

We studied an ethyl acetate (EtoAC) extract of leaves obtained from the medicinal and ornamental tree, Lagerstroemia speciosa L, for nephroprotective activity in cisplatin-induced acute renal injury in Balb/C mice. The EtoAC extract at dose levels of 50 and 250 mg/kg showed a dose-dependent reduction in cisplatin-induced elevations in urea and creatinine concentrations. Additionally, treatment with the EtoAC extract prevented the cisplatin-induced decline of the renal antioxidant enzymes superoxide dismutase, catalase, glutathione peroxidase, and reduced glutathione. The findings suggest that the EtoAC extract from L. speciosa possesses marked nephroprotective activity and could offer a promising role in the treatment of acute renal injury caused by a nephrotoxin like cisplatin.


Assuntos
Cisplatino/toxicidade , Nefropatias/tratamento farmacológico , Lagerstroemia/química , Extratos Vegetais/farmacologia , Acetatos/química , Administração Oral , Animais , Antioxidantes/administração & dosagem , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Catalase/metabolismo , Cisplatino/administração & dosagem , Creatinina/metabolismo , Relação Dose-Resposta a Droga , Feminino , Sequestradores de Radicais Livres/administração & dosagem , Sequestradores de Radicais Livres/isolamento & purificação , Sequestradores de Radicais Livres/farmacologia , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Injeções Intraperitoneais , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Nefropatias/induzido quimicamente , Malondialdeído/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Extratos Vegetais/administração & dosagem , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Superóxido Dismutase/metabolismo
12.
J Natl Cancer Inst ; 92(19): 1564-72, 2000 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-11018092

RESUMO

Exposure of cells to conditions of environmental stress-including heat shock, oxidative stress, heavy metals, or pathologic conditions, such as ischemia and reperfusion, inflammation, tissue damage, infection, and mutant proteins associated with genetic diseases-results in the inducible expression of heat shock proteins that function as molecular chaperones or proteases. Molecular chaperones are a class of proteins that interact with diverse protein substrates to assist in their folding, with a critical role during cell stress to prevent the appearance of folding intermediates that lead to misfolded or otherwise damaged molecules. Consequently, heat shock proteins assist in the recovery from stress either by repairing damaged proteins (protein refolding) or by degrading them, thus restoring protein homeostasis and promoting cell survival. The events of cell stress and cell death are linked, such that molecular chaperones induced in response to stress appear to function at key regulatory points in the control of apoptosis. On the basis of these observations-and on the role of molecular chaperones in the regulation of steroid aporeceptors, kinases, caspases, and other protein remodeling events involved in chromosome replication and changes in cell structure-it is not surprising that the heat shock response and molecular chaperones have been implicated in the control of cell growth. In this review, we address some of the molecular and cellular events initiated by cell stress-the interrelationships between stress signaling, cell death, and oncogenesis-and chaperones as potential targets for cancer diagnosis and treatment.


Assuntos
Apoptose , Proteínas de Choque Térmico/metabolismo , Chaperonas Moleculares/metabolismo , Neoplasias/metabolismo , Neoplasias/terapia , Animais , Células Apresentadoras de Antígenos , Antígenos de Neoplasias/metabolismo , Vacinas Anticâncer/farmacologia , Transformação Celular Neoplásica , Humanos , Hipertermia Induzida , Oncogenes , Proteína Supressora de Tumor p53/metabolismo
13.
Eur Ann Otorhinolaryngol Head Neck Dis ; 133 Suppl 1: S68-71, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27246743

RESUMO

Cochlear implantation (CI) has reached over years of practicing high standards of surgical outcomes. Even patients with significant residual hearing are nowadays benefiting from a cochlear implant. However, the speech perception still depends to great extent on the adequate pitch match between the frequency components delivered by an electrode array and individual cochlear tonotopic map. Compression, deletion or shift of frequency components can be tolerated by patients only to some extent. Furthermore, low frequency information delivered to the cochlear apex is particularly important for spatial hearing. It is therefore important to use the electrode array of an appropriate length for each individual cochlea. The large variability in the anatomy makes this task difficult as a single design does not fit all cochlear shapes. Fortunately, preoperative CT imaging, routinely taken in most of ENT clinics, can be exploited also for the prediction of the cochlear duct length (CDL). It turns out that a single radiological measurement, the diameter of the basal turn, is highly correlated with CDL and its measurement can be used for the informed selection of the most suitable electrode array length from the available array portfolio for each CI patient.


Assuntos
Cóclea/anatomia & histologia , Implante Coclear/métodos , Implantes Cocleares , Ajuste de Prótese , Cóclea/diagnóstico por imagem , Humanos , Desenho de Prótese , Tomografia Computadorizada por Raios X
14.
J Neuroendocrinol ; 28(9)2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27453551

RESUMO

In various vertebrate species, dopamine (DA) exerts an inhibitory action on reproduction. In the European eel, DA plays a pivotal role in the inhibitory control of gonadotroph function and the blockade of puberty. In vivo studies have suggested that this effect is mediated by receptors pharmacologically related to the D2 family. In the European eel, two distinct D2 receptor (D2-R) paralogous genes have been identified (D2A-R and D2B-R) and both were shown to be expressed in the pituitary. We investigated the potential role of each paralogue in the control of gonadotroph function in this species. Eel recombinant D2A-R or D2B-R were expressed in HEK 293 cells, with a universal Gα subunit, and receptor activation was followed by inositol phosphate production. Recombinant D2-Rs exhibited a comparable affinity for DA, although they had differential affinities for mammalian D2-R agonists and antagonists, supporting subtle structure/activity differences. Furthermore, using eel pituitary cell primary cultures, the expression by gonadotroph cells of both native eel D2-R paralogues was examined by in situ hybridisation of D2A-R or D2B-R transcripts, coupled with immunofluorescence of luteinising hormone (LH)ß or follicle-stimulating (FSH)ß. LH and to a lesser extent, FSH cells expressed both D2-R transcripts but with a clear predominance of D2B-R. Notably, D2B-R transcripts were detected for the majority of LH cells. Accordingly, using these cultures, we showed that DA potently inhibited basal and testosterone-stimulated LHß expression and less potently basal and activin-stimulated FSHß expression. We also tested some D2-R antagonists, aiming to select the most adequate one to be used in innovative protocols for induction of eel sexual maturation. We identified eticlopride as the most potent inhibitor of DA action on basal and stimulated LH expression in vitro. Our data suggest a differential functionalisation of the duplicated receptor genes and demonstrate that mainly D2B-R is involved in the dopaminergic inhibitory control of eel gonadotroph function.


Assuntos
Enguias/metabolismo , Proteínas de Peixes/metabolismo , Subunidade beta do Hormônio Folículoestimulante/metabolismo , Gonadotropinas Hipofisárias/metabolismo , Hormônio Luteinizante Subunidade beta/metabolismo , Receptores de Dopamina D2/metabolismo , Animais , Dopamina/administração & dosagem , Antagonistas dos Receptores de Dopamina D2/administração & dosagem , Feminino , Subunidades alfa de Proteínas de Ligação ao GTP/metabolismo , Gonadotropinas Hipofisárias/antagonistas & inibidores , Células HEK293 , Humanos , RNA Mensageiro/metabolismo , Receptores de Dopamina D2/genética
16.
Biochim Biophys Acta ; 1390(3): 258-68, 1998 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-9487147

RESUMO

The ability of two rat liver fatty acid binding protein (L-FABP) isoforms to influence microsomal phosphatidic acid biosynthesis, a key intermediate in glycerolipid formation, and phospholipid fatty acid remodeling was examined in vitro. Isoform I enhanced microsomal incorporation of [1-14C]-oleoyl-CoA into phosphatidic acid 7-fold while isoform II had no effect relative to basal. In contrast, isoform II enhanced microsomal incorporation of [1-14C]-palmitoyl-CoA into phosphatidic acid 4-fold while isoform I had no effect. These results suggest that each L-FABP isoform selectively utilized different acyl-CoAs for glycerol-3-phosphate esterification. Both isoforms stimulated phosphatidic acid formation by increasing glycerol-3-phosphate acyltransferase activity, not by increasing lysophosphatidic acid acyltransferase activity. Furthermore, the effects of L-FABP on phosphatidic acid biosynthesis could not be correlated with protection from acyl-CoA hydrolysis. L-FABP isoforms also influenced phospholipid fatty acid remodeling in a phospholipid-dependent manner. Isoform I preferentially enhanced oleate and palmitate esterification into phosphatidylethanol-amine, while isoform II stimulated esterification into phosphatidylcholine, phosphatidylserine and sphingomyelin. Taken together, these data demonstrated a unique role of each L-FABP isoform in modulating microsomally derived phospholipid fatty acid composition. (c) 1998 Elsevier Science B.V.


Assuntos
Proteínas de Transporte/metabolismo , Ácidos Graxos/análise , Microssomos Hepáticos/metabolismo , Proteína P2 de Mielina/metabolismo , Proteínas de Neoplasias , Proteínas do Tecido Nervoso , Ácidos Fosfatídicos/biossíntese , Fosfolipídeos/química , Acil Coenzima A/metabolismo , Aciltransferases/metabolismo , Animais , Proteínas de Transporte/química , Proteína 7 de Ligação a Ácidos Graxos , Proteínas de Ligação a Ácido Graxo , Ácidos Graxos/química , Glicerol-3-Fosfato O-Aciltransferase/metabolismo , Hidrólise , Masculino , Proteína P2 de Mielina/química , Palmitoil Coenzima A/metabolismo , Palmitoil-CoA Hidrolase/metabolismo , Fosfolipídeos/farmacologia , Ratos , Ratos Sprague-Dawley
17.
Biochim Biophys Acta ; 1483(1): 185-97, 2000 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-10601707

RESUMO

arachidonoyl-CoA. In summary, the data established for the first time a role for both L-FABP and ACBP in microsomal phosphatidic acid biosynthesis. By preferentially stimulating microsomal transacylation of unsaturated long chain fatty acyl-CoAs while concomitantly exerting their differential protection from microsomal acyl-CoA hydrolase, L-FABP and ACBP can uniquely function in modulating the pattern of fatty acids esterified to phosphatidic acid, the de novo precursor of phospholipids and triacylglycerols. This may explain in part the simultaneous presence of these proteins in cell types involved in fatty acid absorption and lipoprotein secretion.


Assuntos
Acil Coenzima A/metabolismo , Proteínas de Transporte/farmacologia , Microssomos Hepáticos/metabolismo , Proteína P2 de Mielina/farmacologia , Proteínas de Neoplasias , Proteínas do Tecido Nervoso , Animais , Inibidor da Ligação a Diazepam , Ativação Enzimática/efeitos dos fármacos , Proteína 7 de Ligação a Ácidos Graxos , Proteínas de Ligação a Ácido Graxo , Glicerol-3-Fosfato O-Aciltransferase/metabolismo , Masculino , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/enzimologia , Palmitoil Coenzima A/metabolismo , Ácidos Fosfatídicos/biossíntese , Ratos , Ratos Sprague-Dawley
18.
Biochim Biophys Acta ; 1299(1): 146-54, 1996 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-8555247

RESUMO

The effect of ras transformation (rasB fibroblasts) on basal and serum-stimulated diacylglycerol (DAG) composition and mass was examined over time with respect to changes in membrane phospholipid composition and ceramide mass. RasB cells vs. nontransformed control cells (rasD and NR6) had chronically elevated DAG levels (up to 240 min) following serum stimulation, indicating a defect in the recovery phase of the intracellular DAG pulse. Ras transformation also had a dramatic effect on DAG composition. Molecular species analysis revealed that DAG from unstimulated rasB cells was enriched in the delta 9 desaturase fatty acyl species (monoenoate 18:1(n - 7) and 18:1(n - 9)), and depleted in arachidonic acid (20:4(n - 6)). With the exception of glycerophosphoinositol (GPI), DAG remodeling paralleled the compositional alterations in individual phospholipid classes. Importantly, ras transformation altered the fatty acyl composition of sphingomyelin, a precursor to the ceramide second messenger. With the addition of serum, control cells (rasD) had a progressive increase in ceramide mass with levels approximately 5-fold higher by 240 min. In contrast, ceramide levels did not increase in rasB cells at either 4 or 240 min. These results demonstrate that ras-oncogene, in addition to its effects on DAG metabolism, can also abolish the cellular increase in ceramide mass in response to serum stimulation. Since DAG and ceramide may have opposing biological functions, the prolonged elevation of DAG and the suppression of ceramide levels would be consistent with an enhanced proliferative capacity.


Assuntos
Diglicerídeos/metabolismo , Genes ras , Esfingolipídeos/metabolismo , Células 3T3 , Animais , Linhagem Celular Transformada , Ceramidas/análise , Diglicerídeos/análise , Diglicerídeos/química , Ácidos Graxos/análise , Camundongos , Fosfatidiletanolaminas/química , Fosfolipídeos/análise , Sistemas do Segundo Mensageiro
19.
Leukemia ; 8(7): 1202-13, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8035613

RESUMO

The mechanism by which non-oncogene-bearing, slowly transforming retroviruses induce leukemia is not well understood, but appears to represent a multi-step process. Cell lines have been isolated following in vitro infection of lymphoid cells with radiation leukemia virus (RadLV) and they have been used to develop a two-step model for leukemia development. Thymic tumors were induced when one of the cell lines, C1-V13D, was inoculated into CBA/H mouse thymus. Upon reisolation of C1-V13D cells after one, two and three passages through thymus, individual cloned cell lines displayed increased tumorigenic potential compared with the non-tumorigenic parental line. Southern analysis has been used to track any genetic changes occurring while cells undergo further transformation and become increasingly tumorigenic. Specifically, retrovirus integration has been monitored in clones derived from C1-V13D at the primary, secondary and tertiary passage through thymus using probes specific for long terminal repeat (LTR), gag, pol and env genes of RadLV. The data indicate multiple ecotropic retrovirus integration sites in C1-V13D cells. Primary thymic tumors also showed the integration of a new recombinant or defective virus. There was no evidence that new ecotropic retrovirus integration had occurred during subsequent passage of primary tumors through the thymus, i.e. during the progression to oncogenesis. All data indicate an important role for the thymic environment in the development of a fully transformed cell.


Assuntos
Transformação Celular Viral/efeitos da radiação , Leucemia Experimental/genética , Leucemia Experimental/microbiologia , Oncogenes/efeitos da radiação , Vírus da Leucemia Induzida por Radiação/genética , Animais , Divisão Celular/fisiologia , DNA Viral/genética , Modelos Animais de Doenças , Feminino , Masculino , Camundongos , Camundongos Endogâmicos CBA , Timo/citologia , Timo/microbiologia , Neoplasias do Timo/microbiologia , Neoplasias do Timo/patologia , Integração Viral
20.
Mol Plant Microbe Interact ; 7(4): 528-30, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-8075424

RESUMO

Four potato clones with host gene-mediated resistance to potato leafroll virus (PLRV) multiplication were transformed with the PLRV coat protein (CP) gene. Plants of lines expressing high levels of transcript were highly resistant to PLRV multiplication; virus concentration was only 20-40 ng/g of leaf, which is approximately 1% of the concentration reached in susceptible cultivars. The effects of the transgenic and host-derived resistance genes appear to be additive.


Assuntos
Capsídeo/genética , Doenças das Plantas/microbiologia , Vírus de Plantas/crescimento & desenvolvimento , Solanum tuberosum/genética , Imunidade Inata/genética , Vírus de Plantas/genética , Plantas Geneticamente Modificadas , Solanum tuberosum/microbiologia
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