Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Int J Dermatol ; 55(2): e62-71, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26266670

RESUMO

BACKGROUND: Mycosis fungoides (MF) is the most common primary cutaneous T-cell lymphoma (CTCL), followed by CD30+ lymphoproliferative disorders, including lymphomatoid papulosis (LyP) and primary cutaneous anaplastic large cell lymphoma (pcALCL). The objective was to report on a series of patients with different types of CTCL at different times in their clinical course, with a focus on clonality studies. METHODS: Four patients with multiple diagnoses of CTCLs were identified. The clinical information, treatment interventions, and histopathology were reviewed. T-cell receptor (TCR) gene rearrangement studies were performed on all available specimens. RESULTS: The four patients carried diagnoses of: (1) pcALCL and MF; (2) pcALCL, LyP, and pcALCL; (3) LyP, MF, and pcALCL; (4) LyP, pcALCL, and MF; each with characteristic presentation and histopathologic findings. The results of the TCR polymerase chain reaction showed that all tumors expressed and retained a TCR clone(s) as follows: (1) biallelic clone; (2) single clone; (3) biallelic clone with additional clone; and (4) single clone, respectively. CONCLUSION: We report a series of four cases of individual patients with coexisting diagnoses of some combination of MF, LyP, and pcALCL, whose lesions presented in nontraditional sequence and demonstrated a retained clone by gene rearrangement analysis.


Assuntos
Genes Codificadores dos Receptores de Linfócitos T , Linfoma Anaplásico Cutâneo Primário de Células Grandes/genética , Papulose Linfomatoide/genética , Micose Fungoide/genética , Segunda Neoplasia Primária/genética , Neoplasias Cutâneas/genética , Idoso de 80 Anos ou mais , Alelos , Feminino , Rearranjo Gênico , Humanos , Antígeno Ki-1/análise , Linfoma Anaplásico Cutâneo Primário de Células Grandes/química , Linfoma Anaplásico Cutâneo Primário de Células Grandes/patologia , Papulose Linfomatoide/metabolismo , Papulose Linfomatoide/patologia , Masculino , Pessoa de Meia-Idade , Micose Fungoide/química , Micose Fungoide/patologia , Segunda Neoplasia Primária/química , Segunda Neoplasia Primária/patologia , Neoplasias Cutâneas/química , Neoplasias Cutâneas/patologia , Adulto Jovem
2.
Am J Dermatopathol ; 35(4): 452-7, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23694823

RESUMO

Melanocytic nevus rests in lymph nodes are a known diagnostic challenge, especially in patients with a history of melanoma. Reticulin and NM23 have been studied in this context. The pattern of reticulin staining in melanomas surrounds groups/nests of melanocytes but individual cells in benign nevi. NM23, a metastasis-suppressor gene, has an association with metastatic potential in melanomas and some carcinomas. Twenty-eight cases (14 cases of metastatic melanoma to lymph nodes and 14 cases of lymph node nevus rests, all confirmed with Melan-A staining) were stained with reticulin and NM23. The pattern of reticulin staining was reported as surrounding groups if staining was noted in approximately 5-10 melanocytes in greater than 50% of the lesion but was otherwise reported as surrounding individual melanocytes. Cytoplasmic staining was considered to represent reactivity for NM23. Reticulin staining around groups of melanocytes was identified in all 14 cases of metastatic melanoma. Regarding nodal nevus rest cases, 12 of 14 cases (86%) demonstrated staining around individual melanocytes, whereas in 2 cases, reticulin surrounded melanocytic groups. NM23 staining was equivocal in all cases. Reticulin staining reliably invests groups of melanocytes in cases of metastatic melanoma, whereas in nodal nevus rests, it predominantly surrounds individual melanocytes. NM23 demonstrated no discriminatory value in this analysis. In cases in which a collection of melanocytes is present within a lymph node, reticulin deposition around individual melanocytes supports a diagnosis of lymph nodal nevus rest.


Assuntos
Biomarcadores Tumorais/análise , Linfonodos/química , Melanócitos/química , Melanoma/química , Nucleosídeo NM23 Difosfato Quinases/análise , Nevo Pigmentado/química , Reticulina/análise , Neoplasias Cutâneas/química , Idoso , Biópsia , Feminino , Humanos , Imuno-Histoquímica , Linfonodos/patologia , Metástase Linfática , Antígeno MART-1/análise , Masculino , Melanócitos/patologia , Melanoma/secundário , Nevo Pigmentado/patologia , Neoplasias Cutâneas/patologia , Estados Unidos
3.
Mod Pathol ; 24(9): 1169-76, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21572406

RESUMO

Recent studies have shown that the recurrent t(6;9)(q22-23;p23-24) translocation in adenoid cystic carcinoma results in a novel fusion of the MYB proto-oncogene with the transcription factor gene NFIB. To determine the frequency of this finding, we used RT-PCR assays of the MYB and MYB-NFIB fusion transcripts, and immunohistochemistry for the MYB protein, to study adenoid cystic carcinomas and other epithelial tumors of the salivary glands, and head and neck region. MYB-NFIB fusion transcript was detected in 25 of 29 (86%) frozen adenoid cystic carcinoma tumor samples, and in 14 of 32 (44%) formalin-fixed paraffin-embedded adenoid cystic carcinoma tumor specimens. In contrast, the MYB-NFIB fusion was not expressed in non-adenoid cystic carcinoma neoplasms of the head and neck, confirming the high specificity of the MYB-NFIB fusion. Adenoid cystic carcinomas from various anatomic sites, including salivary gland, sinonasal cavity, tracheobronchial tree, larynx, breast, and vulva were repeatedly fusion-positive, indicating that adenoid cystic carcinomas located in different anatomic sites not only have important morphologic features in common, but also probably evolve through activation of the same molecular pathways. Studies of the expression of MYB revealed that 89% of the tumors, including both fusion-positive and fusion-negative cases, overexpressed MYB RNA. Similarly, 82% of adenoid cystic carcinomas stained positive for MYB protein, compared with 14% of non-adenoid cystic carcinoma neoplasms, indicating that MYB immunostaining may be useful for the diagnosis of adenoid cystic carcinoma, but that neoplasms sometimes in the differential diagnosis are also labeled. The latter are, however, fusion-negative. In summary, our studies show that MYB activation through gene fusion or other mechanisms is a major oncogenic event in adenoid cystic carcinoma occurring at various anatomic sites. In addition to being a diagnostically useful biomarker for adenoid cystic carcinoma, MYB and its downstream effectors are also novel potential therapeutic targets.


Assuntos
Carcinoma Adenoide Cístico/genética , Proteínas Oncogênicas v-myb/biossíntese , Proteínas de Fusão Oncogênica/genética , Neoplasias das Glândulas Salivares/genética , Adulto , Idoso , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/genética , Carcinoma Adenoide Cístico/metabolismo , Feminino , Genes myb , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Proteínas Oncogênicas v-myb/genética , Proto-Oncogene Mas , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias das Glândulas Salivares/metabolismo , Adulto Jovem
4.
J Cutan Pathol ; 38(1): 67-72, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20002651

RESUMO

Two of the most challenging areas in dermatopathology are lymphoproliferative disorders and melanocytic lesions. We present a case of peripheral T-cell lymphoma occurring with an intradermal melanocytic proliferation. A 63-year-old Caucasian man presented with a 12-cm edematous, erythematous to violaceous, scalp ulceration that had enlarged over six months. Previous biopsies showed reactive changes which were concerning for infection. The last biopsies showed small to intermediate sized, angulated cells with clear cytoplasm within the dermis, with extension into the epidermis. These cells stained positive with markers for CD3, CD45RO and CD43, yet showed decreased expression of pan-T-cell markers CD5 and CD7, and absent expression of CD4, CD8, CD56 and CD57 and EBV. Molecular studies showed a clonal T-cell receptor gamma chain gene rearrangement. The diagnosis was peripheral T-cell lymphoma, unspecified. Another biopsy from an indurated area separate from the ulcer showed scattered, enlarged cells embedded in the same lymphocytic infiltrate. No mitotic figures were identified. These cells stained for S100 and Melan-A, in a partly nested arrangement. This was felt to represent a melanocytic nevus. This case likely represents an extraordinary coincidence of two distinctly different neoplasms.


Assuntos
Linfoma Cutâneo de Células T/patologia , Neoplasias Primárias Múltiplas/patologia , Nevo Pigmentado/patologia , Neoplasias Cutâneas/patologia , Biomarcadores Tumorais/análise , Proliferação de Células , Eczema/complicações , Humanos , Linfoma Cutâneo de Células T/complicações , Linfoma Cutâneo de Células T/metabolismo , Masculino , Melanócitos/metabolismo , Melanócitos/patologia , Pessoa de Meia-Idade , Neoplasias Primárias Múltiplas/metabolismo , Nevo Pigmentado/metabolismo , Couro Cabeludo/metabolismo , Couro Cabeludo/patologia , Neoplasias Cutâneas/metabolismo , Úlcera Cutânea/etiologia , Úlcera Cutânea/metabolismo , Úlcera Cutânea/patologia
5.
Biomaterials ; 31(18): 4898-908, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20334909

RESUMO

Polyphosphazene-polyester blends are attractive materials for bone tissue engineering applications due to their controllable degradation pattern with non-toxic and neutral pH degradation products. In our ongoing quest for an ideal completely miscible polyphosphazene-polyester blend system, we report synthesis and characterization of a mixed-substituent biodegradable polyphosphazene poly[(glycine ethyl glycinato)(1)(phenyl phenoxy)(1)phosphazene] (PNGEG/PhPh) and its blends with a polyester. Two dipeptide-based blends namely 25:75 (Matrix1) and 50:50 (Matrix2) were produced at two different weight ratios of PNGEG/PhPh to poly(lactic acid-glycolic acid) (PLAGA). Blend miscibility was confirmed by differential scanning calorimetry, Fourier transform infrared spectroscopy, and scanning electron microscopy. Both blends resulted in higher tensile modulus and strength than the polyester. The blends showed a degradation rate in the order of Matrix2

Assuntos
Substitutos Ósseos/química , Dipeptídeos/química , Compostos Organofosforados/química , Poliésteres/química , Polímeros/química , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Animais , Substitutos Ósseos/metabolismo , Proliferação de Células , Células Cultivadas , Dipeptídeos/metabolismo , Glicolatos/química , Ácido Láctico , Masculino , Teste de Materiais , Compostos Organofosforados/metabolismo , Osteoblastos/citologia , Osteoblastos/metabolismo , Poliésteres/metabolismo , Ácido Poliglicólico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Polímeros/metabolismo , Ratos , Ratos Sprague-Dawley
6.
J Cutan Pathol ; 37(7): 744-50, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20184665

RESUMO

BACKGROUND: Atypical fibroxanthoma (AFX) is a pleomorphic spindle cell lesion of the skin; it is considered in the differential diagnosis with spindle cell malignant melanoma (MM) and sarcomatoid carcinoma/spindle cell squamous cell carcinoma (SCC). An optimum approach has yet to fully emerge with respect to the immunohistochemical discrimination of these lesions. METHODS: Departmental archives from 1978 onwards were searched for clinicopathologically confirmed cases of AFX, MM and SCC. Immunostains for CD10, CD99 and p63 were performed in each case. Scored staining results were analyzed using Fisher's Exact Test. RESULTS: Twenty-seven of 31 cases of AFX were positive for CD10, as compared with 3 of 22 SCCs and 0 of 20 MMs. CD10 positivity was preferentially associated with the diagnosis of AFX (p < 0.001). p63 reactivity was observed in 15/22 cases of SCCs, 5/31 AFXs and 1/20 MMs. CD99 reactivity was observed in 3/31 cases of AFX, 2/22 SCCs and 3/20 MMs. CONCLUSION: CD10 positivity is relatively specific in this context for the diagnosis of AFX. Its utility is enhanced when only strong, diffuse membranocytoplasmic staining is considered as a positive result. In contrast to prior reports, p63 was not found to be highly sensitive for SCC. Similarly, CD99 showed no preferential staining of any single diagnostic group of lesions.


Assuntos
Biomarcadores Tumorais/análise , Carcinoma de Células Escamosas/diagnóstico , Histiocitoma Fibroso Benigno/diagnóstico , Melanoma/diagnóstico , Neoplasias Cutâneas/diagnóstico , Antígeno 12E7 , Idoso , Idoso de 80 Anos ou mais , Antígenos CD/biossíntese , Carcinoma de Células Escamosas/metabolismo , Moléculas de Adesão Celular/biossíntese , Diagnóstico Diferencial , Feminino , Histiocitoma Fibroso Benigno/metabolismo , Humanos , Imuno-Histoquímica , Masculino , Melanoma/metabolismo , Proteínas de Membrana/biossíntese , Pessoa de Meia-Idade , Neprilisina/biossíntese , Neoplasias Cutâneas/metabolismo
7.
Appl Immunohistochem Mol Morphol ; 18(3): 226-30, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20042851

RESUMO

Podoplanin, D2-40, is often used for highlighting lymphatics. However, it has been described in a variety of normal and neoplastic tissues. We evaluated the expression of D2-40 in breast, salivary gland, skin, and mucosa, all organs rich in myoepithelial cells and basal cells. This study assessed the utility of using D2-40 to highlight basal/myoepithelial cells and to identify potential pitfalls in misinterpretation of lymphatic invasion. Our results showed that myoepithelial cells in breast and salivary gland and basal cells in prostate consistently demonstrate D2-40 immunoreactivity, but typically less intensely than lymphatics. Cutaneous and mucosal-based basal cells also have D2-40 expression, but often in a patchy, focal manner. In addition, many salivary gland tumors and squamous cell carcinomas had strong D2-40 expression, sometimes making distinction of lymphatics versus tumor edge staining difficult. D2-40 is excellent for assessing lymphatic invasion in breast, prostate, and cervix as long as the pathologist is aware of the expression in myoepithelial cells/basal cells to avoid misinterpretation of ductal carcinoma in situ or normal prostate glands or tumor stroma retraction as tumor lymphatic invasion. Given the patchy positivity in basal cells of skin and mucosa and the reactivity in squamous cell carcinoma, D2-40 was not helpful in assessing for microinvasion of squamous cell carcinoma.


Assuntos
Metástase Linfática/diagnóstico , Glicoproteínas de Membrana/metabolismo , Neoplasias/diagnóstico , Neoplasias/patologia , Anticorpos Monoclonais , Mama/metabolismo , Mama/patologia , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Erros de Diagnóstico , Feminino , Humanos , Imuno-Histoquímica , Vasos Linfáticos/metabolismo , Vasos Linfáticos/patologia , Masculino , Glicoproteínas de Membrana/imunologia , Mucosa/metabolismo , Mucosa/patologia , Neoplasias/metabolismo , Próstata/metabolismo , Próstata/patologia , Neoplasias das Glândulas Salivares/diagnóstico , Neoplasias das Glândulas Salivares/metabolismo , Neoplasias das Glândulas Salivares/patologia , Glândulas Salivares/metabolismo , Glândulas Salivares/patologia , Pele/metabolismo , Pele/patologia
8.
Ann Clin Lab Sci ; 39(4): 339-44, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19880760

RESUMO

The objectives of this prospective, cross-sectional study were to characterize blood donors in an academic-based hospital donor center, to determine whether physicians donate, and to elucidate the donation impetus. A confidential survey was issued to presenting, potential donors over 200 weekdays. Three questions were asked: their role at the institution, if and when they had previously donated blood, and what prompted the current donation. The majority of the 687 respondents were institution-affiliated (73.5%) and 79.3% had previously donated, with a median of 3 mo since the prior donation. Only 21 (3.1%) respondents were physicians. The predominant reasons for donor presentation were an appointment, knowing it had been 8 wk since the last donation, and contact by the blood center to donate. This study shows the dearth of physician blood donors and a strong cohort of institution-affiliated repeat donors. Physicians represent a potential, stable, and sustainable donor pool; further studies are needed to establish physician recruitment programs.


Assuntos
Centros Médicos Acadêmicos , Doadores de Sangue/estatística & dados numéricos , Médicos/estatística & dados numéricos , Doadores de Sangue/psicologia , Estudos Transversais , Pesquisas sobre Atenção à Saúde/estatística & dados numéricos , Humanos , Médicos/psicologia , Autorrelato , Virginia
9.
Int J Gynecol Pathol ; 27(4): 491-5, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18753974

RESUMO

Differentiation of Müllerian serous carcinoma from metastatic breast carcinoma is a challenging and frequent diagnostic dilemma, particularly in the setting of a pelvic mass or peritoneal carcinomatosis. Precise classification is important as it impacts treatment and prognosis. Antibodies exist that assist with this differential but they are often limited by low sensitivity or specificity. This study evaluated the utility of mesothelin and mammaglobin antibodies in differentiating breast carcinoma (particularly those with a papillary morphology) from Müllerian serous carcinomas. Formalin-fixed, paraffin-embedded archival tissue from 21 breast carcinomas (10 micropapillary, 11 usual type ductal carcinomas) and 20 serous carcinomas (12 ovarian and 8 uterine) in addition to 6 cases of metastatic breast cancer to the ovary (5 cases) and cervix (1 case) were evaluated for the pattern and intensity of reactivity to antibodies to mesothelin, mammaglobin, and GCDFP-15. None of the breast carcinomas stained for mesothelin, whereas 8/12 and 3/8 ovarian and uterine serous carcinomas were positive; however, 7 of these had less than 10% positivity. Mammaglobin was negative in all serous carcinomas. When compared with GCDFP-15, mammaglobin was more frequently and diffusely expressed in breast carcinomas (GCDFP-15 positivity in 8/21 and mammaglobin positivity in 14/21). This study indicates that the addition of mammaglobin to immunohistochemical panels is useful in distinguishing metastatic breast carcinoma from a new primary ovarian or uterine malignancy. Mesothelin is extremely specific in this scenario but can be technically challenging to interpret due to the common patchy, focal staining.


Assuntos
Neoplasias da Mama/diagnóstico , Carcinoma Papilar/diagnóstico , Glicoproteínas de Membrana/análise , Proteínas de Neoplasias/análise , Neoplasias Ovarianas/diagnóstico , Neoplasias Uterinas/diagnóstico , Uteroglobina/análise , Anticorpos Monoclonais/química , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Carcinoma Ductal/diagnóstico , Carcinoma Ductal/metabolismo , Carcinoma Ductal/secundário , Carcinoma Papilar/metabolismo , Carcinoma Papilar/patologia , Proteínas de Transporte/análise , Proteínas de Transporte/biossíntese , Diagnóstico Diferencial , Feminino , Proteínas Ligadas por GPI , Glicoproteínas/análise , Glicoproteínas/biossíntese , Humanos , Imuno-Histoquímica , Mamoglobina A , Glicoproteínas de Membrana/biossíntese , Proteínas de Membrana Transportadoras , Mesotelina , Proteínas de Neoplasias/biossíntese , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/secundário , Estudos Retrospectivos , Neoplasias Uterinas/metabolismo , Neoplasias Uterinas/secundário , Uteroglobina/biossíntese
10.
Am J Clin Pathol ; 130(3): 363-8, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18701408

RESUMO

Intraoperative frozen section (FS) consultation is used in evaluating possible infection in cases of hip and knee revision arthroplasty, serving as an adjunct to preoperative and intraoperative studies. We examined our experience for more than 11 years to determine if FS examination had value when sections were sent nonselectively. We reviewed 244 cases, 132 with available culture results. The criterion for the presence of acute inflammation was more than 5 polymorphonuclear leukocytes per high-power field (hpf) in at least 5 separate hpfs, excluding surface inflammatory exudate and fibrin. Only 27 cases (11.1%) demonstrated positive FS or paraffin section results. In comparison with intraoperative culture, the sensitivity, specificity, positive predictive value, and negative predictive value for FS analysis alone (on review) were 29%, 95%, 40%, and 92%. As currently used, FS analysis has excellent specificity and negative predictive value but poor sensitivity and positive predictive value. We suggest that FS examination be used more selectively in conjunction with other studies, namely erythrocyte sedimentation rate and C-reactive protein.


Assuntos
Artroplastia de Quadril , Artroplastia do Joelho , Secções Congeladas , Articulação do Quadril/microbiologia , Articulação do Joelho/microbiologia , Artrite/diagnóstico , Artroplastia de Quadril/efeitos adversos , Artroplastia do Joelho/efeitos adversos , Articulação do Quadril/patologia , Humanos , Período Intraoperatório , Articulação do Joelho/patologia , Valor Preditivo dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
11.
Ultrastruct Pathol ; 31(1): 63-71, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17455099

RESUMO

Penile malignancies are rare in developed countries. The authors present a case of a penile urethral mesenchymal tumor occurring in a 51-year-old Caucasian male and displaying light microscopic, immunohistochemical, and ultrastructural features suggestive of a pacemaker cell type, combined with a lack of diagnostic features of any other established tumor category. The immunohistochemical profile was intensely positive for vimentin, PKC theta, and NSE and weakly positive to nonreactive for CD34 and smooth muscle actin, and entirely negative for CD117 (c-kit), S-100, and other markers. C-kit and PDGFRA gene analysis showed no mutations. Electron microscopy revealed tumor cells with plentiful cytoplasm and cytoplasmic processes/filopodia, both filled with intermediate filaments and occasional solitary focal densities. There were also prominent smooth endoplasmic reticulum cisternae, caveolae, neurosecretory granules, particularly concentrated in cytoplasmic processes, and synaptic-type structures. Poorly formed basal lamina, gap junctions, and intercellular collagen aggregates, consistent with skeinoid-type fibers, were also noted. Interstitial cells with potential pacemaker function have been recently described in the lower urinary tract, including the urethra, and this tumor may be related to this cellular phenotype.


Assuntos
Tumor de Células de Leydig/ultraestrutura , Neoplasias Testiculares/ultraestrutura , Neoplasias Uretrais/ultraestrutura , Actinas/análise , Antígenos CD34/análise , Análise Mutacional de DNA , Humanos , Imuno-Histoquímica , Isoenzimas/análise , Tumor de Células de Leydig/química , Tumor de Células de Leydig/genética , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Fenótipo , Proteína Quinase C/análise , Proteína Quinase C-theta , Células Estromais/ultraestrutura , Neoplasias Testiculares/química , Neoplasias Testiculares/genética , Neoplasias Uretrais/química , Neoplasias Uretrais/genética , Vimentina/análise
12.
J Investig Med ; 52(2): 129-36, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15068229

RESUMO

BACKGROUND: Insulin increases endothelial nitric oxide (NO) production by activating endothelial nitric oxide synthase (eNOS) through protein kinase B (Akt)-mediated phosphorylation of serine residue 1179 (p-eNOS serine 1179). Because fatty acids modulate insulin-stimulated Akt signaling cascades in smooth muscle cells, we hypothesized that fatty acids would differentially regulate endothelial Akt signaling, eNOS phosphorylation, and NO production. METHODS: Porcine pulmonary artery endothelial cells (PAECs) were treated for 3 hours with 100 microM oleic (18:1) or eicosapentaenoic (20:5) acids or with an equivalent volume of ethanol vehicle (0.1%). PAECs were then treated with graded concentrations (10(9)-10(-5) M) of insulin or incubated overnight (24 hours) in culture medium without fatty acids before insulin treatment. Activation and phosphorylation of Akt and eNOS were determined by immunoblotting. NO production was measured with a chemiluminescence NO analyzer or with a NO-selective carbon fiber microelectrode. RESULTS: Insulin-stimulated Akt phosphorylation, eNOS phosphorylation, and NO production. The phosphatidylinositol-3 kinase inhibitor wortmannin attenuated insulin-stimulated Akt activation and NO production. Treatment with the omega-3 fatty acid 20:5, but not 18:1, enhanced insulin-stimulated NO production but failed to alter insulin-stimulated Akt activation or eNOS serine 1179 phosphorylation. CONCLUSION: Individual fatty acyl species have distinct effects on insulin-stimulated endothelial NO production. Although fatty acids alter Akt signaling in muscle cells, the current results indicate that fatty acids do not modulate endothelial NO production through alterations in insulin-stimulated, Akt-mediated eNOS phosphorylation.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Ácidos Graxos/farmacologia , Insulina/farmacologia , Óxido Nítrico/metabolismo , Proteínas Serina-Treonina Quinases , Proteínas Proto-Oncogênicas/metabolismo , Androstadienos/farmacologia , Animais , Western Blotting , Células Cultivadas , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Ácido Eicosapentaenoico , Endotélio Vascular/metabolismo , Ácidos Graxos Ômega-3/farmacologia , Ácidos Graxos Insaturados/farmacologia , Ácido Oleico/farmacologia , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Proto-Oncogênicas c-akt , Artéria Pulmonar , Suínos , Wortmanina
13.
Comp Funct Genomics ; 4(1): 56-65, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-18629113

RESUMO

Our studies on the bases of codons from 11 completely sequenced archaeal genomes show that, as we move from GC-rich to AT-rich protein-coding gene-containing species, the differences between G and C and between A and T, the purine load (AG content), and also the overall persistence (i.e. the tendency of a base to be followed by the same base) within codons, all increase almost simultaneously, although the extent of increase is different over the three positions within codons. These findings suggest that the deviations from the second parity rule (through the increasing differences between complementary base contents) and the increasing purine load hinder the chance of formation of the intra-strand Watson-Crick base-paired secondary structures in mRNAs (synonymous with the protein-coding genes we dealt with), thereby increasing the translational efficiency. We hypothesize that the ATrich protein-coding gene-containing archaeal species might have better translational efficiency than their GC-rich counterparts.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...