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1.
Clin Radiol ; 73(9): 810-817, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29895386

RESUMO

AIM: To validate the diagnostic accuracy of Prostate Imaging-Reporting and Data System (PI-RADS) version 2 in detecting clinically significant prostate cancer (csPCa, Gleason score ≥7) on prebiopsy biparametric MRI (bpMRI) in patients with different prostate-specific antigen (PSA) levels. MATERIALS AND METHODS: This retrospective study included 184 patients who underwent prebiopsy bpMRI followed by transrectal ultrasonography-guided biopsy between June 2015 and February 2017. Reader 1 performed a combination of systematic and targeted biopsy with cognitive fusion after reviewing bpMRI and reader 2 reviewed the bpMRIs retrospectively. PI-RADS categories 4 and 5 were considered positive, and the results of the biopsy were considered the reference standard. Diagnostic performance of PI-RADS of bpMRI was evaluated in two PSA groups with a PSA cut-off level of 10 ng/ml and compared to PSA and the PSA density using receiver operating characteristics (ROC) curve analysis. RESULTS: csPCa was diagnosed in 24 of 123 patients (19.5%) and 26 of 61 patients (42.6%) in the low and high PSA groups, respectively. A PI-RADS v2 category by either readers 1 or 2 had a significantly better performance to detect csPCa than PSA in both PSA groups. In the high PSA group, only one csPCa was missed by reader 2, but none by reader 1. In the low PSA group, readers 1 and 2 were unable to detect seven and five of the 24 csPCas, respectively. CONCLUSION: Prebiopsy bpMRI has good performance for detecting csPCa in the high PSA group but may miss small-volume csPCa in the low PSA group.


Assuntos
Imageamento por Ressonância Magnética/métodos , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/patologia , Idoso , Biomarcadores Tumorais/sangue , Humanos , Biópsia Guiada por Imagem/métodos , Masculino , Gradação de Tumores , Estudos Retrospectivos , Sensibilidade e Especificidade , Ultrassonografia de Intervenção
2.
Clin Otolaryngol ; 42(3): 687-692, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27886463

RESUMO

BACKGROUND: Although many factors have been found to be involved in recovery from Bell's palsy, no study has investigated the association between recovery from Bell's palsy and obesity. This study therefore evaluated the association between recovery from Bell's palsy and body mass index (BMI). METHODS: Subjects were classified into five groups based on BMI (kg/m2 ). Demographic and clinical characteristics were compared among these groups. Assessed factors included sex, age, time from paralysis to visiting a hospital, the presence of comorbidities such as diabetes mellitus and hypertension, degree of initial facial nerve paralysis by House-Brackmann (H-B) grade and neurophysiological testing, and final recovery rate. RESULTS: Based on BMI, 37 subjects were classified as underweight, 169 as normal weight, 140 as overweight, 155 as obese and 42 as severely obese. Classification of the degree of initial facial nerve paralysis as moderate or severe, according to H-B grade and electroneurography, showed no difference in severity of initial facial paralysis among the five groups (P > 0.05). However, the final recovery rate was significantly higher in the normal weight than in the underweight or obese group (P < 0.05). CONCLUSIONS: Obesity or underweight had no effect on the severity of initial facial paralysis, but the final recovery rate was lower in the obese and underweight groups than in the normal group.


Assuntos
Paralisia de Bell/fisiopatologia , Índice de Massa Corporal , Expressão Facial , Paralisia Facial/fisiopatologia , Obesidade/complicações , Recuperação de Função Fisiológica , Idoso , Paralisia de Bell/complicações , Paralisia Facial/etiologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/fisiopatologia , Estudos Retrospectivos
4.
Clin Otolaryngol ; 40(3): 183-90, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25346100

RESUMO

OBJECTIVES: To compare the recovery rates of patients with idiopathic sudden sensorineural hearing loss (ISSHL) treated with oral systemic steroids (PO) or intratympanic steroid injection (IT) or both. DESIGN: A retrospective observational study. SETTING: Tertiary referral centre. PARTICIPANTS: Eight hundred and forty-four patients diagnosed with ISSHL within 14 days of the onset of symptoms. The patients were divided into three groups by treatment modality. MAIN OUTCOME MEASURES: Threshold of pure-tone tests, age, accompanying symptoms and underlying diseases were compared. The level of final hearing recovery was evaluated by the application of the results of the pure-tone test that was performed at least 3 months after the completion of each treatment. RESULTS: Final hearing recovery rate differed significantly by the type of treatment (P = 0.031). Recovery rates in the PO and combined groups were significantly higher in patients with mild (85.1% and 88.6%, respectively) than with profound (52.8% and 69.0%, respectively) hearing loss (P < 0.05). In contrast, severity and recovery rate were not significantly correlated in the IT group (P > 0.05). Combined treatment yielded significantly higher recovery rates than other treatment modalities in patients without hypertension (HTN) and diabetes mellitus (DM) (P = 0.021). CONCLUSION: In the group treated with combined therapy, better hearing improvement was obtained than in the groups treated with systemic steroid only or with intratympanic steroid injection only without complications. These findings suggest that the combination of systemic administration and intratympanic injection may improve patient prognosis.


Assuntos
Dexametasona/administração & dosagem , Perda Auditiva Neurossensorial/tratamento farmacológico , Perda Auditiva Súbita/tratamento farmacológico , Audição/fisiologia , Administração Oral , Audiometria de Tons Puros , Feminino , Glucocorticoides/administração & dosagem , Perda Auditiva Neurossensorial/fisiopatologia , Perda Auditiva Súbita/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Resultado do Tratamento
5.
Eur Radiol ; 23(4): 1150-7, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22868482

RESUMO

OBJECTIVE: To compare three-dimensional (3D) T2-weighted turbo spin-echo (TSE) with multiplanar two-dimensional (2D) T2-weighted TSE for the evaluation of invasive cervical carcinoma. METHODS: Seventy-five patients with cervical carcinoma underwent MRI of the pelvis at 3.0 T, using both 5-mm-thick multiplanar 2D (total acquisition time = 12 min 25 s) and 1-mm-thick coronal 3D T2-weighted TSE sequences (7 min 20 s). Quantitative analysis of signal-to-noise ratio (SNR) and qualitative analysis of image quality were performed. Local-regional staging was performed in 45 patients who underwent radical hysterectomy. RESULTS: The estimated SNR of cervical carcinoma and the relative tumour contrast were significantly higher on 3D imaging (P < 0.0001). Tumour conspicuity was better with the 3D sequence, but the sharpness of tumour margin was better with the 2D sequence. No significant difference in overall image quality was noted between the two sequences (P = 0.38). There were no significant differences in terms of the diagnostic accuracy, sensitivity, and specificity of parametrial invasion, vaginal invasion, and lymph node metastases. CONCLUSION: Multiplanar reconstruction 3D T2-weighted imaging is largely equivalent to 2D T2-weighted imaging for overall image quality and staging accuracy of cervical carcinoma with a shorter MR data acquisition, but has limitations with regard to the sharpness of the tumour margin.


Assuntos
Algoritmos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Neoplasias Uterinas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Aumento da Imagem/métodos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
J Nanosci Nanotechnol ; 11(7): 6298-305, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22121705

RESUMO

The partial oxidation of dimethyl ether (DME) was investigated using the structured catalyst Rh/Al2O3/Al. The porous Al2O3 layer was synthesized on the aluminum plate through anodic oxidation in an oxalic-acid solution. It was observed that about 20 nm nanopores were well developed in the Al2O3 layer. The thickness of Al2O3 layer can be adjusted by controlling the anodizing time and current density. After pore-widening and hot-water treatment, the Al2O3/Al plate was calcined at 500 degrees C for 3 h. The obtained delta-Al2O3 had a specific surface area of 160 m2/g, making it fit to be used as a catalyst support. A microchannel reactor was designed and fabricated to evaluate the catalytic activity of Rh/Al2O3/Al in the partial oxidation of DME. The structured catalyst showed an 86% maximum hydrogen yield at 450 degrees C. On the other hand, the maximum syngas yield by a pack-bed-type catalyst could be attained by using a more than fivefold Rh amount compared to that used in the structured Rh/Al2O3/Al catalyst.

7.
J Laryngol Otol ; 125(2): 214-6, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20868538

RESUMO

OBJECTIVE: We report a case of weakness of the buccal branch of the facial nerve after a canine fossa puncture procedure. METHOD: A case report and literature review are presented. RESULTS: A 52-year-old woman diagnosed with right chronic maxillary sinusitis underwent canine fossa puncture during endoscopic sinus surgery. Immediately after the operation, she complained of motor weakness of the right upper lip and oral commissure, in the area innervated by the buccal branch of the facial nerve. Electroneurography revealed incomplete paralysis of the right buccal branch. However, facial weakness had recovered spontaneously by three months post-operatively, with no permanent disability. CONCLUSION: This is the first reported case of an injury to the buccal branch of the facial nerve following canine fossa puncture. Although the incidence of this complication is very low, surgeons should inform their patients of the possibility, and should take care when choosing the puncture site.


Assuntos
Traumatismos do Nervo Facial/etiologia , Paralisia Facial/etiologia , Sinusite Maxilar/cirurgia , Punções/efeitos adversos , Bochecha/inervação , Endoscopia , Feminino , Humanos , Sinusite Maxilar/diagnóstico por imagem , Pessoa de Meia-Idade , Pólipos Nasais/cirurgia , Radiografia
8.
Allergy ; 66(5): 637-44, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21121930

RESUMO

BACKGROUND: In addition to the dysregulation of arachidonic acid metabolism in aspirin-intolerant asthma (AIA), aspirin acetylsalicylic acid (ASA) exerts effects on inflammation and immunity; however, many of these effects are unknown. OBJECTIVE: The aim of the study was to evaluate the methylation status of whole genome in blood and polyp tissues with and without aspirin hypersensitivity. METHODS: Genome-wide DNA methylation levels in nasal polyps and peripheral blood cells were examined by microarray analysis using five subjects with AIA and four subjects with aspirin-tolerant asthma (ATA). RESULTS: In the nasal polyps of the patients with AIA, hypermethylation was detected at 332 loci in 296 genes, while hypomethylation was detected at 158 loci in 141 genes. Gene ontologic and pathway enrichment analyses revealed that genes involved in lymphocyte proliferation, cell proliferation, leukocyte activation, cytokine biosynthesis, cytokine secretion, immune responses, inflammation, and immunoglobulin binding were hypomethylated, while genes involved in ectoderm development, hemostasis, wound healing, calcium ion binding, and oxidoreductase activity were hypermethylated. In the arachidonate pathway, PGDS, ALOX5AP, and LTB4R were hypomethylated, whereas PTGES was hypermethylated. CONCLUSION: The nasal polyps of patients with AIA have characteristic methylation patterns affecting 337 genes. The genes and pathways identified in this study may be associated with the presence of aspirin hypersensitivity in asthmatics and are therefore attractive targets for future research.


Assuntos
Aspirina/imunologia , Asma/imunologia , Metilação de DNA , Hipersensibilidade a Drogas/genética , Genoma Humano/genética , Pólipos Nasais/genética , Adulto , Idoso , Asma/genética , Células Sanguíneas , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Análise em Microsséries , Pessoa de Meia-Idade
10.
Br J Radiol ; 82(974): e23-6, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19168684

RESUMO

Lipomatous haemangiopericytoma (a fat-forming solitary fibrous tumour) is a rare soft-tissue tumour histologically characterized by haemangiopericytomatous vasculature and the presence of mature adipocytes. We report the CT and MRI findings of a case of lipomatous haemangiopericytoma involving the perineum. CT showed a well-circumscribed soft-tissue density mass containing a small area of fat density and a punctuate calcification. On MR images, the mass was mostly isointense to the muscle on T(1) weighted images, with heterogeneous signal intensity on T(2) weighted images, and showed strong contrast enhancement except for the fatty and dense collagenous components. This is the first case report of imaging findings of a lipomatous haemangiopericytoma in the radiological literature. Although rare, lipomatous haemangiopericytoma should be considered as a differential diagnosis of fat-containing, hypervascular soft-tissue tumours with variable signal intensity on T(2) weighted images.


Assuntos
Hemangiopericitoma/diagnóstico , Lipoma/diagnóstico , Períneo , Tumores Fibrosos Solitários/diagnóstico , Adulto , Hemangiopericitoma/diagnóstico por imagem , Hemangiopericitoma/patologia , Humanos , Lipoma/diagnóstico por imagem , Lipoma/patologia , Imageamento por Ressonância Magnética , Masculino , Tumores Fibrosos Solitários/diagnóstico por imagem , Tumores Fibrosos Solitários/patologia , Tomografia Computadorizada por Raios X
11.
Br J Radiol ; 81(971): e269-71, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18941040

RESUMO

Haemangioma is an extremely rare tumour of the ovary. We describe the CT and MRI findings of a heavily calcified ovarian haemangioma in a 69-year-old woman presenting with adnexal torsion. CT showed a well-circumscribed mass with extensive punctate calcifications, located posterior to the uterus. MR images showed dark signal intensities of the mass on both T(1) and T(2) weighted images, with poor enhancement of the mass on contrast-enhanced T(1) weighted images. MR images also demonstrated a beak-like protrusion from the adnexal mass, representing the adnexal torsion. This is the first case report of a heavily calcified ovarian haemangioma in the English literature. Although rare, ovarian haemangioma should be included in the differential diagnosis of a heavily calcified adnexal mass.


Assuntos
Calcinose/diagnóstico , Hemangioma Cavernoso/diagnóstico , Neoplasias Ovarianas/diagnóstico , Doenças dos Anexos/diagnóstico , Idoso , Calcinose/patologia , Diagnóstico Diferencial , Feminino , Hemangioma Cavernoso/patologia , Humanos , Imageamento por Ressonância Magnética , Neoplasias Ovarianas/patologia , Tomografia Computadorizada por Raios X
12.
Clin Radiol ; 63(5): 529-35, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18374716

RESUMO

AIM: To evaluate the magnetic resonance (MR) imaging features of ovarian fibromas, emphasizing the presence and shape of the ovary on the same side of the fibroma. MATERIALS AND METHODS: MR images from 23 patients with 24 histologically proven ovarian fibromas were reviewed by two radiologists. Eleven were pre-menopausal and 12 were postmenopausal. The presence and shape of the ovarian tissue on the same side of the fibroma were evaluated on T2-weighted MR images. RESULTS: In 11 (46%) of the 24 ovarian fibromas, the ipsilateral ovary was detected on T2-weighted images. The ovary was crescent-shaped along the periphery of the fibroma in six (55%) of 11 fibromas and had a normal, oval shape in five (45%). Of these five tumours, the ovary was connected to the fibromas by a pedicle-like structure in three and was closely attached to the periphery of the fibromas in two. The ipsilateral ovary was detected in 10 (83%) of 12 fibromas in pre-menopausal patients, and in one (8%) of 12 fibromas in postmenopausal patients. There was a statistically significant difference (p=0.001) in the presence of detectable ipsilateral ovary between pre-menopausal and postmenopausal women. CONCLUSIONS: Detection of the remaining ovary on the same side as the fibroma is not unusual on MRI, especially in pre-menopausal women, and the shape of the ovary may be normal in cases of fibromas with exophytic growth from the periphery of the ovary.


Assuntos
Fibroma/diagnóstico , Neoplasias Ovarianas/diagnóstico , Ovário/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Estudos Retrospectivos
13.
Cell Signal ; 18(11): 2013-21, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16723209

RESUMO

Atrial natriuretic peptide (ANP) and the closely-related peptides BNP and CNP are highly conserved cardiovascular hormones. They bind to single transmembrane-spanning receptors, triggering receptor-intrinsic guanylyl cyclase activity. The "truncated" type-C natriuretic peptide receptor (NPR-C) has long been called a clearance receptor because it lacks the intracellular guanylyl cyclase domain, though data suggest it might negatively couple to adenylyl cyclase via G(i). Here we report the molecular cloning and characterization of the Xenopus laevis type-C natriuretic peptide receptor (XNPR-C). Analysis confirms the presence of a short intracellular C-terminus, as well as a high similarity to fish and mammalian NPR-C. Injection of XNPR-C mRNA into Xenopus oocytes resulted in expression of high affinity [(125)I]ANP binding sites that were competitively and completely displaced by natriuretic analogs and the unrelated neuropeptide vasoactive intestinal peptide (VIP). Measurement of cAMP levels in mRNA-injected oocytes revealed that XNPR-C is negatively coupled to adenylyl cyclase in a pertussis toxin-sensitive manner. When XNPR-C was co-expressed with PAC(1) receptors for pituitary adenylyl cyclase-activating polypeptide (PACAP), VIP and natriuretic peptides counteracted the cAMP induction by PACAP. These results suggest that VIP and natriuretic peptides can potentially modulate the action of PACAP in cells where these receptors are co-expressed.


Assuntos
Oócitos/metabolismo , Receptores do Fator Natriurético Atrial/genética , Receptores do Fator Natriurético Atrial/metabolismo , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Transdução de Sinais , Peptídeo Intestinal Vasoativo/metabolismo , Adenilil Ciclases/metabolismo , Sequência de Aminoácidos , Animais , Ligação Competitiva , Clonagem Molecular , DNA Complementar/genética , Humanos , Dados de Sequência Molecular , Oócitos/efeitos dos fármacos , RNA Mensageiro/metabolismo , RNA Mensageiro/farmacologia , Ratos , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/antagonistas & inibidores , Alinhamento de Sequência , Peptídeo Intestinal Vasoativo/farmacologia , Xenopus
14.
Abdom Imaging ; 31(1): 45-7, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16132430

RESUMO

Chilaiditi syndrome is a condition in which the colon or small intestine is interposed temporarily or permanently between the liver and the diaphragm. Usually, it is an asymptomatic and incidental radiographic finding, but it may be a potential source of abdominal problems, ranging from intermittent mild abdominal pain to acute intestinal obstruction. We report multidetector computed tomographic findings of a case of Chilaiditi syndrome presenting as small bowel obstruction due to hepatodiaphragmatic interposition of the ileal loop, which was entrapped by adhesive bands caused by Fitz-Hugh-Curtis syndrome.


Assuntos
Diafragma/patologia , Hepatite/complicações , Obstrução Intestinal/diagnóstico por imagem , Intestino Delgado/patologia , Tomografia Computadorizada por Raios X/métodos , Idoso , Infecções por Chlamydia/complicações , Chlamydia trachomatis , Feminino , Hepatite/etiologia , Hepatite/patologia , Humanos , Obstrução Intestinal/etiologia , Doença Inflamatória Pélvica/complicações , Doença Inflamatória Pélvica/microbiologia , Síndrome , Aderências Teciduais
15.
Br J Radiol ; 74(878): 142-6, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11718385

RESUMO

To evaluate the helical CT findings of ruptured hepatocellular carcinoma (HCC), 12 patients with ruptured HCC were reviewed with regard to the tumour's location, size and contour protrusion, the appearance of the mass, the enhancement pattern, multiplicity and secondary changes. All ruptured tumours were located at the periphery of the liver and had a protruding contour. The maximum diameter of tumours ranged from 2 cm to 16 cm. Discontinuity of the hepatic surface was seen in 11 cases. In eight cases, CT images during the arterial phase showed a non-enhancing low attenuating lesion with focal discontinuity and peripheral rim enhancement. Seven cases showed separation of tumour content from the peripheral enhancing rim and intraperitoneal rupture of tumour content into the perihepatic space. Because of the similar appearance to an enucleated orbital globe with remaining sclera, this was termed the "enucleation sign". As well as ruptured masses, 10 cases with non-ruptured masses also showed a non-enhancing low attenuating pattern. Seven cases showed a haematoma with high attenuation around the ruptured mass. The peripheral location, protruding contour, discontinuity of the hepatic surface and surrounding haematoma are helpful signs in the diagnosis of ruptured HCC. The "enucleation sign" may be a characteristic finding in ruptured HCC.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Adulto , Idoso , Carcinoma Hepatocelular/patologia , Seguimentos , Hematoma/diagnóstico por imagem , Humanos , Hepatopatias/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Ruptura Espontânea/diagnóstico por imagem , Tomografia Computadorizada por Raios X
17.
J Biol Chem ; 276(47): 43668-76, 2001 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-11553633

RESUMO

To identify neural tumor cell lines that could be used as models to study growth-related natriuretic peptide actions, we determined the effects of these peptides on the proliferation of human and rodent neuroblastoma cell lines. Subnanomolar concentrations of atrial natriuretic peptide (ANP) and type C natriuretic peptide (CNP) stimulated proliferation in all four cell lines. These actions were associated with cGMP elevation and were blocked by a protein kinase G inhibitor. These data imply the involvement of guanylyl cyclase (GC)-coupled natriuretic receptors. However, higher concentrations of ANP and CNP, and low concentrations of des-[Gln(18),Ser(19),Gly(20),Leu(21),Gly(22)]-ANP(4-23)-NH(2) (desANP(4-23)) (analog for NPR-C receptor) exerted antiproliferative actions in three of the cell lines. These effects were insensitive to a protein kinase G inhibitor and to HS-142-1, suggesting that growth-inhibitory actions involved a non-GC receptor. They did not appear to involve cAMP, protein kinase A, protein kinase C, or calcium mobilization but were abolished when constitutive mitogen-activated protein kinase activity was inhibited. Radioligand binding experiments revealed the presence of a uniform class of binding sites in NG108 cells and multiple binding sites in Neuro2a cells. Northern and reverse transcriptase-polymerase chain reaction analyses revealed differential gene expression for NPR-A/B/C in NG108 and Neuro2a cells. The results indicate that natriuretic peptides stimulate neuroblastoma cell proliferation through type NPR-A/B (GC) receptors. Higher concentrations of ANP and CNP exerted a mitogen-activated protein kinase-dependent antiproliferative action mediated by a non-GC receptor that interacts with desANP(4-23) with relatively high affinity.


Assuntos
Fator Natriurético Atrial/farmacologia , Divisão Celular/efeitos dos fármacos , Guanilato Ciclase/metabolismo , Neuroblastoma/patologia , Fator Natriurético Atrial/química , Sequência de Bases , Dados de Sequência Molecular , Receptores do Fator Natriurético Atrial/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
18.
J Neurosci ; 21(11): 3849-59, 2001 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-11356873

RESUMO

The neuropeptide pituitary adenylyl cyclase-activating peptide (PACAP) and one of its receptors (PAC(1)) are expressed in embryonic neural tube, where they appear to regulate neurogenesis and patterning. We now show that PAC(1) gene expression is also present in neonatal rats in the ventricular and subventricular zones and in the optic chiasm, areas that are rich in oligodendrocyte (OL) progenitors (OLP). Because actions of PACAP on OLP have not been reported, we examined the effects of PACAP on the proliferation of purified OLP in culture and on myelinogenesis in cerebellar slices. Northern analyses on total RNA from purified glial cell subtypes revealed an abundant 7 kb hybridizing transcript in OLP, which was confirmed to correspond to the PAC(1) receptor by reverse transcription-PCR. The presence of this receptor was also corroborated by radioligand binding and cAMP assay. In cultured OL, receptor density decreased during maturation but was partially counterbalanced by the appearance of sites that bound both PACAP and the related peptide vasoactive intestinal peptide. PACAP increased DNA synthesis in OLP cultures almost twofold and increased the bromodeoxyuridine-labeling index in O4-positive OLP. PACAP treatment also resulted in decreased sulfate incorporation into sulfatide in cultures of differentiating OL. The PACAP effect on sulfatide synthesis was fully reproduced in a cerebellar explant model. These findings indicate that PACAP may act at two stages during OL development to (1) stimulate proliferation and (2) delay maturation and/or myelinogenesis.


Assuntos
Diferenciação Celular/efeitos dos fármacos , DNA/metabolismo , Neuropeptídeos/metabolismo , Oligodendroglia/citologia , Células-Tronco/metabolismo , Animais , Animais Recém-Nascidos , Ligação Competitiva/efeitos dos fármacos , Bromodesoxiuridina , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Cerebelo/citologia , Cerebelo/efeitos dos fármacos , Cerebelo/metabolismo , Ventrículos Cerebrais/citologia , Ventrículos Cerebrais/metabolismo , Ventrículos Cerebrais/cirurgia , Expressão Gênica , Hibridização In Situ , Técnicas In Vitro , Bainha de Mielina/metabolismo , Neuropeptídeos/farmacologia , Quiasma Óptico/citologia , Quiasma Óptico/metabolismo , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , RNA Mensageiro/metabolismo , Ensaio Radioligante , Ratos , Ratos Wistar , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Receptores do Hormônio Hipofisário/biossíntese , Receptores do Hormônio Hipofisário/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células-Tronco/efeitos dos fármacos
19.
Radiographics ; 20(3): 779-94, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10835128

RESUMO

Vasculitides can cause local or diffuse pathologic changes in the gastrointestinal tract, resulting in nonspecific paralytic ileus, mesenteric ischemia, submucosal edema and hemorrhage, or bowel perforation or stricture. The extent and clinical course of disease depend on the size and location of the affected vessel and the histologic characteristics of the lesion. Vasculitis may primarily involve large vessels (eg, giant cell arteritis, Takayasu arteritis), medium-sized vessels (eg, polyarteritis nodosa, Kawasaki disease, primary granulomatous central nervous system vasculitis), or small vessels (eg, Wegener granulomatosis, Churg-Strauss syndrome, microscopic polyangiitis, Henoch-Schönlein syndrome, systemic lupus erythematosus, rheumatoid vasculitis, Behçet syndrome). Radiologic findings in various types of vasculitis often overlap considerably and therefore have limited value in making a specific diagnosis. Nevertheless, the possibility of vasculitis should be considered whenever mesenteric ischemic changes occur in young patients, are noted at unusual sites (eg, stomach, duodenum, rectum), have a tendency to concomitantly involve the small and large intestine, and are associated with genitourinary involvement. Knowledge of systemic clinical manifestations in affected patients may suggest and even help establish the specific diagnosis.


Assuntos
Angiografia , Sistema Digestório/irrigação sanguínea , Tomografia Computadorizada por Raios X , Vasculite/diagnóstico por imagem , Diagnóstico Diferencial , Sistema Digestório/patologia , Humanos , Vasculite/etiologia , Vasculite/patologia
20.
J Comput Assist Tomogr ; 24(3): 407-12, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10864076

RESUMO

PURPOSE: The purpose of this study was to evaluate the radiological features of 12 pathologically proven cases of colorectal leiomyomatous tumors. METHOD: A retrospective analysis of radiologic findings was performed in 12 patients with pathologically proven colorectal leiomyomatous tumors (2 leiomyomas and 10 leiomyosarcomas). Available radiologic studies included abdominal CT scans in 11 patients, double contrast barium studies in 4, and pelvic MRI in 1. On imaging, we evaluated the size, tumor margin (smooth or lobulated), morphologic appearance, growth patterns (endocolic, exocolic, or combined), contrast enhancement patterns, presence or absence of calcification within the tumors, and metastasis. RESULTS: The involved tumor sites were the colon in 2 patients and the rectum in 10. The mean tumor size was 7.9 cm (range 2-15 cm): It was 3.5 cm in leiomyomas and 8.8 cm in leiomyosarcomas. On imaging studies, the tumor margin was smooth in three patients and lobulated in nine, with endocolic growth in one, exocolic in four, and combined in the remaining seven. Eight of the 12 tumors showed varying degrees of internal necrosis with heterogeneous contrast enhancement. Dystrophic calcification was noted in five patients. Metastasis was seen in the liver in three patients at the time of initial diagnosis, and lymphadenopathy was noted in two patients (paraaortic space in one and perirectal space in two). CONCLUSION: Although rare, the diagnosis of leiomyomatous tumor may be suggested especially when the tumor occurring in the colorectum shows exocolic growth or calcification with varying degree of internal necrosis.


Assuntos
Neoplasias Colorretais/diagnóstico por imagem , Leiomioma/diagnóstico por imagem , Leiomiossarcoma/diagnóstico por imagem , Adolescente , Adulto , Idoso , Neoplasias Colorretais/patologia , Feminino , Humanos , Leiomioma/patologia , Leiomiossarcoma/patologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
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