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1.
Mol Cell Biol ; 17(4): 2005-13, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9121448

RESUMO

We report that the competitive translational activity of alfalfa mosaic virus coat protein mRNA (CP RNA), a nonadenylated mRNA, is determined in part by the 3' untranslated region (UTR). Competitive translation was characterized both in vitro, with cotranslation assays, and in vivo, with microinjected Xenopus laevis oocytes. In wheat germ extracts, coat protein synthesis was constant when a fixed amount of full-length CP RNA was cotranslated with increasing concentrations of competitor globin mRNA. However, translation of CP RNA lacking the 3' UTR decreased significantly under competitive conditions. RNA stabilities were equivalent. In X. laevis oocytes, which are translationally saturated and are an inherently competitive translational environment, full-length CP RNA assembled into large polysomes and coat protein synthesis was readily detectable. Alternatively, CP RNA lacking the 3' UTR sedimented as small polysomes, and little coat protein was detected. Again, RNA stabilities were equivalent. Site-directed mutagenesis was used to localize RNA sequences or structures required for competitive translation. Since the CP RNA 3' UTR has an unusually large number of AUG nucleotide triplets, two AUG-containing sites were altered in full-length RNA prior to oocyte injections. Nucleotide substitutions at the sequence GAUG, 20 nucleotides downstream of the coat protein termination codon, specifically reduced full-length CP RNA translation, while similar substitutions at the next AUG triplet had little effect on translation. The competitive influence of the 3' UTR could be explained by RNA-protein interactions that affect translation initiation or by ribosome reinitiation at downstream AUG codons, which would increase the number of ribosomes committed to coat protein synthesis.


Assuntos
Vírus do Mosaico da Alfafa/genética , Capsídeo/genética , RNA Mensageiro/genética , RNA Viral/genética , Vírus do Mosaico da Alfafa/metabolismo , Animais , Sequência de Bases , Capsídeo/biossíntese , Códon/genética , Células HeLa , Humanos , Técnicas In Vitro , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Conformação de Ácido Nucleico , Oócitos/metabolismo , Polirribossomos/metabolismo , Biossíntese de Proteínas , RNA Mensageiro/química , RNA Viral/química , Triticum/genética , Triticum/metabolismo , Xenopus laevis
2.
Invest Ophthalmol Vis Sci ; 32(9): 2610-21, 1991 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1869413

RESUMO

Research has shown that androgens regulate the production of secretory component (SC), the IgA antibody receptor, by lacrimal gland acinar cells in vivo. This study was designed to establish an optimal culture system to permit analysis of this endocrine-acinar cell interrelationship in vitro. Acinar cells were isolated from male rat lacrimal glands and cultured on Matrigel (Collaborative Research, Bedford, MA) in serum-free Dulbecco's modified Eagle's medium (DMEM)/Ham's F12 media that contained a variety of supplements. Under these conditions, acinar cells responded to dihydrotestosterone (DHT) exposure with a significant increase in SC output. Replacement of the DMEM/Ham's F12 media base with either Modified Eagle's Medium (MEM) or low-calcium MEM inhibited this hormone response and dramatically reduced cell recovery after 4 days of culture. Similarly, decreased concentrations or deletions of selected media supplements, including insulin, which binds to acinar cells, and dexamethasone, led to a significant diminution in the extent of androgen action, as well as to a decline in cell maintenance. In contrast, removal of high-density lipoprotein from culture media or the addition of fetal bovine serum (FBS) or cholera toxin significantly enhanced basal and DHT-associated SC production by acinar cells. With regard to extracellular matrices, Matrigel proved to be superior to collagen type I, laminin, fibronectin, or the Primaria (Falcon, Oxnard, CA) plastic surface in providing support for acinar cell association or hormone-related function. In summary, our results show that the media formulation, supplement profile, and extracellular matrix composition are important for maximal expression of androgen-induced effects by lacrimal gland acinar cells in vitro.


Assuntos
Androgênios/fisiologia , Técnicas Citológicas , Aparelho Lacrimal/metabolismo , Componente Secretório/biossíntese , Animais , Sítios de Ligação , Materiais Biocompatíveis/farmacologia , Fenômenos Fisiológicos Sanguíneos , Água Corporal/metabolismo , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Meios de Cultura , Insulina/metabolismo , Insulina/farmacologia , Aparelho Lacrimal/citologia , Masculino , Mitógenos/farmacologia , Concentração Osmolar , Ratos , Transferrina/farmacologia
3.
Invest Ophthalmol Vis Sci ; 30(1): 145-58, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2536359

RESUMO

The objectives of the current investigation were fourfold: (1) to establish an effective procedure for the isolation of acinar cells from the rat lacrimal gland; (2) to evaluate the functional capacity of freshly isolated cells; (3) to determine defined culture conditions which permit maintenance of viable, differentiated cells, as well as secretory component (SC) production, during long-term culture; and (4) to characterize the morphological features of cultured cells. Acinar cells were isolated by serial incubation of gland fragments in chelating and enzymatic solutions, followed by centrifugation through a Ficoll gradient. The yield of viable cells/gland appeared to be age-dependent: cell recovery was inversely proportional to the age of the animals. Immunofluorescence analysis of freshly isolated cells showed the presence of SC, the IgA antibody receptor, within isolated cells. In addition, experiments with a labeled analog (Nle4-D-Phe7-alpha MSH) of alpha-melanocyte-stimulating hormone (alpha-MSH) demonstrated specific binding sites on freshly isolated cells; alpha-MSH is a known modulator of acinar protein secretion. Maximum binding of the alpha-MSH analog occurred within 30 min, was dependent upon cell density and was reduced by coincubation with unlabeled alpha-MSH. To determine the culture requirements of acinar cells, cells were cultured on a variety of substrates (plastic or modified plastic [Primaria], coated with or without extracellular matrix [Matrigel]) in the presence or absence of various supplements and/or fetal calf serum (FCS) for 0.7 to 3.5 weeks. Cell attachment, function and long-term viability required an extracellular matrix. Moreover, in long term cultures (25 days), acinar cell attachment was enhanced by the inclusion of supplements to media containing 10% FCS. Replacement of serum with fibroblast growth factor, high-density lipoprotein and an increased concentration of epidermal growth factor resulted in a distinct "cobblestone" morphology characteristic of epithelial cell cultures. Electron microscopic analysis of cells cultured in supplemented serum-free media demonstrated extensive rough endoplasmic reticulum and Golgi, intermediate filaments and numerous secretory granules, as well as tight junctions and desmosomes. In addition to cell maintenance and attachment, acinar cell synthesis and/or secretion of SC was positively influenced by inclusion of supplements in the media. In summary, we have isolated lacrimal gland acinar cells, which express receptors for IgA antibodies and alpha-MSH. In addition, we have defined culture conditions which permit the long-term maintenance of SC-secreting acinar cells.


Assuntos
Aparelho Lacrimal/citologia , Animais , Adesão Celular , Separação Celular , Sobrevivência Celular , Células Cultivadas , Meios de Cultura , Aparelho Lacrimal/metabolismo , Aparelho Lacrimal/ultraestrutura , Masculino , Microscopia Eletrônica , Ratos , Ratos Endogâmicos , Componente Secretório/biossíntese , Componente Secretório/metabolismo , Fatores de Tempo , alfa-MSH/metabolismo
4.
Invest Ophthalmol Vis Sci ; 27(8): 1255-60, 1986 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3733369

RESUMO

The upper tarsal conjunctival epithelium was analyzed for inflammatory cell profile and accompanying morphological changes in a guinea pig system with histopathology resembling two human ocular diseases: vernal conjunctivitis and contact lens-associated giant papillary conjunctivitis (GPC). Female Hartley strain guinea pigs were immunized intradermally on day 0 with 200 micrograms keyhole limpet hemocyanin (KLH) and challenged on day 6 with varying doses of KLH by injection beneath the conjunctival epithelium of one lid and phosphate-buffered saline in the contralateral lid. Tissues containing the reaction site were examined by light microscopy. The 50 micrograms dose of KLH elicited the maximal accumulation of basophils and eosinophils. These values were significantly higher than in the PBS-injected control. Injection of KLH, PBS, or insertion of a sterile needle into unsensitized animals, and uninjected tissue served as additional controls. Neutrophils were significantly higher in the epithelium of the traumatized tissue (repeated needle insertions) than in the uninjected control. Basophils and mast cells were rarely found in the epithelium of unsensitized animals. Epithelial thickening, quantified by a Zeiss Videoplan2 Image Analysis system (Zeiss, West Germany), was greatest in the traumatized tissue, followed by the KLH-challenged tissue of sensitized animals. These values were significantly greater than that of the PBS-injected lid or of naive animals, uninjected or KLH-injected. These results indicate that epithelial changes can be induced by both antigen and trauma. Such epithelial changes may have a role in both vernal conjunctivitis and giant papillary conjunctivitis.


Assuntos
Túnica Conjuntiva/imunologia , Conjuntivite Alérgica/patologia , Hipersensibilidade Tardia/imunologia , Animais , Basófilos , Túnica Conjuntiva/lesões , Modelos Animais de Doenças , Eosinófilos , Epitélio/patologia , Pálpebras/imunologia , Pálpebras/lesões , Feminino , Cobaias , Hemocianinas/imunologia
5.
Invest Ophthalmol Vis Sci ; 28(12): 1970-7, 1987 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3679747

RESUMO

We investigated the cellular profile of inflammatory infiltrate during development of a guinea pig conjunctival basophil hypersensitivity lesion at 1, 6, 24, 48, and 72 hr following injection of keyhole limpet hemocyanin (KLH). Neutrophils reached maximal accumulation at 6 hr. Eosinophils and basophils reached maximal accumulation at 24 hr. Basophil numbers remained high at 48 hr and were lower at 72 hr. The number of stromal monocytes did not vary significantly from PBS-injected tissues at any time. Mast cell number decreased at 24 hr following antigen challenge. Morphologic evidence for intense secretory activity was seen in cells at the stromal reaction site. Secretion channels and evidence of intense degranulation was seen from electron microscopy of neutrophils, eosinophils, and basophils. Inflammatory cells migrate through the basement membrane into the conjunctival epithelium. After maximal accumulation there was a decrease in the number of inflammatory cell types in the epithelium.


Assuntos
Basófilos/patologia , Doenças da Túnica Conjuntiva/patologia , Hipersensibilidade/patologia , Animais , Basófilos/imunologia , Doenças da Túnica Conjuntiva/imunologia , Eosinófilos/imunologia , Eosinófilos/patologia , Eosinófilos/ultraestrutura , Epitélio/imunologia , Epitélio/patologia , Feminino , Cobaias , Hipersensibilidade/imunologia , Inflamação/imunologia , Inflamação/patologia , Mastócitos/imunologia , Mastócitos/patologia , Microscopia Eletrônica , Monócitos/imunologia , Monócitos/patologia , Neutrófilos/imunologia , Neutrófilos/patologia , Neutrófilos/ultraestrutura
6.
Peptides ; 11(3): 477-83, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2166277

RESUMO

The specific melanotropin (MSH) binding sites of rat lacrimal glands were characterized with respect to anatomic distribution, peptide specificity and selectivity, and coupling to a biological response. Tissue distribution of MSH binding sites was determined by autoradiography following in situ binding of a radiolabeled, biologically active preparation of a superpotent alpha-MSH analog, [125I]-[Nle4,D-Phe7]-alpha-MSH ([125I]-NDP-MSH). Intense, specific (i.e., alpha-MSH-displaceable) [125I]-NDP-MSH binding was observed throughout lacrimal acinar tissue, but not in ducts or stroma. In freshly isolated lacrimal acinar cells, specific binding of [125I]-NDP-MSH was maximal within 30 min and rapidly reversible, with a dissociation half-time of about 15 min. A number of melanotropins [alpha-MSH, [N,O-diacetyl-Ser1]-alpha-MSH, [des-acetyl-Ser1]-alpha-MSH, beta-MSH, ACTH(1-24) and ACTH(1-39)] were recognized by these binding sites, as assessed by their inhibition of [125I]-NDP-MSH binding; NDP-MSH was the most potent (IC50 = 1.3 x 10(-9) M). In contrast, other peptides, including ACTH(4-10) and the nonmelanotropic peptides VIP, substance P, somatostatin, and ACTH(18-39) (CLIP), had no effects on tracer binding. In isolated lacrimal acinar cells, alpha-MSH and NDP-MSH stimulated intracellular cyclic AMP accumulation. We conclude that lacrimal acinar cells express functional receptors recognizing melanotropins, suggesting that the lacrimal gland may be a target for physiological regulation by endogenous melanotropins.


Assuntos
Aparelho Lacrimal/análise , Receptores do Hormônio Hipofisário/análise , alfa-MSH/metabolismo , Animais , AMP Cíclico/metabolismo , Técnicas In Vitro , Aparelho Lacrimal/citologia , Masculino , Ensaio Radioligante , Ratos , Ratos Endogâmicos , Receptores do Hormônio Hipofisário/fisiologia
7.
Fertil Steril ; 39(4): 464-7, 1983 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-6403388

RESUMO

Eighty cycles induced by human menopausal gonadotropins in 45 women were studied with serial ultrasound examinations. The incidence of ovarian hyperstimulation (OHS) was 44%, considerably higher than in other series using similar induction protocols. This was probably due to the superior ability of ultrasound to detect ovarian enlargement and the withholding of human chorionic gonadotropin until at least one follicle had reached a minimum size of 15 mm. No difference was found between the mean urinary estrogen levels of those in whom mild or moderate OHS developed and those in whom it did not. It is concluded that the development of OHS is a frequent but acceptable result of ovulation induction.


Assuntos
Ovário/efeitos dos fármacos , Indução da Ovulação , Ultrassonografia , Amenorreia/tratamento farmacológico , Gonadotropina Coriônica/farmacologia , Estrogênios/urina , Feminino , Humanos , Menotropinas/farmacologia , Cistos Ovarianos/tratamento farmacológico , Doenças Ovarianas/diagnóstico , Ovulação/efeitos dos fármacos
8.
J Am Coll Surg ; 179(5): 513-7, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7952451

RESUMO

BACKGROUND: Transrectal ultrasonography (TRUS) supplements clinical evaluation of early carcinoma of the rectum in selecting patients for local operative therapy, such as transanal excision (TAE). STUDY DESIGN: This study was done to evaluate the accuracy of ultrasonographic staging of tumor depth (T stage) in patients with suspected early carcinoma of the rectum, to compare ultrasonographic with clinical T-staging accuracies within this patient group, to determine if any specific tumor characteristics (configuration, size, location) predispose toward ultrasonographic T-staging inaccuracy, and to examine the role of TRUS in operative selection for patients with early carcinoma of the rectum. RESULTS: Between April 1990 and December 1992, 62 patients with primary carcinoma of the rectum underwent ultrasonographic staging (uT), whereby three uT4, 27 uT3, 24 uT2 and eight uT1 carcinomas were identified. Of the 32 patients with suspected intramural (uT1 or uT2) disease, 27 underwent prompt operative excision or resection at our institution, allowing comparative histopathologic staging. In this highly selected patient subset, uT1 staging was correct in all instances; uT2 staging was incorrect in 45 percent of instances, with 30 percent having unpredicted transmural penetration. Ultrasonographic and clinical staging accuracies were quantitatively similar, and no tumor characteristics were consistently associated with ultrasonographic imprecision. CONCLUSIONS: Among patients with clinically suspected early carcinoma of the rectum, the decision to perform TAE is supported by ultrasonographic T1 staging. By contrast, the decision to perform TAE cannot be based solely on ultrasonographic T2 staging, because of the possibility for transmural penetration of tumor.


Assuntos
Carcinoma/diagnóstico por imagem , Carcinoma/cirurgia , Seleção de Pacientes , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Retais/patologia , Reto/patologia , Reto/cirurgia , Ultrassonografia/métodos
9.
J Am Coll Surg ; 192(5): 577-83, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11333094

RESUMO

BACKGROUND: Previous studies have shown that intraoperative ultrasonography (IOUS) during hepatic resection for malignancy changes the operative plan or identifies occult unresectable disease in a large proportion of patients. This study was undertaken to reassess the yield of IOUS in light of recent improvements in preoperative staging. STUDY DESIGN: Patients with potentially resectable primary or metastatic hepatic malignancies subjected to exploration, bimanual palpation of the liver, and IOUS were evaluated prospectively. Intraoperative findings were recorded, and preoperative imaging studies were reanalyzed by radiologists blinded to the intraoperative findings. The extent of disease based on preoperative imaging was compared with the intraoperative findings. RESULTS: From October 1997 until November 1998, 111 patients were evaluated. At exploration, a total of 77 new findings or findings different than suggested on the imaging studies were identified in 61 patients (55%), the most common of which was additional hepatic tumors (n = 37). Thirty-five of 77 (45%) new findings were identified by IOUS alone and 10 (13%) by palpation alone; the remainder were identified by both palpation and IOUS. Forty-seven of 61 patients (77%) underwent a complete resection despite new intraoperative findings, with a modification (n = 28) or no change (n = 19) in the planned operation. Twenty-one patients (19%) had new findings identified only on IOUS. Thirteen of these patients underwent resection with no change in the operative plan, six underwent a modified resection and two were considered to have unresectable disease based solely on the findings of IOUS. CONCLUSIONS: In patients with hepatic malignancies submitted to a potentially curative resection, new intraoperative findings or findings different than suggested on preoperative imaging studies are common. But resection with no change in the operative plan or a modified resection is still possible in the majority of patients despite such findings. The findings on IOUS alone rarely lead to a change in the operative plan.


Assuntos
Hepatectomia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Monitorização Intraoperatória/métodos , Idoso , Feminino , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/secundário , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Monitorização Intraoperatória/normas , Estadiamento de Neoplasias , Seleção de Pacientes , Portografia , Estudos Prospectivos , Tomografia Computadorizada por Raios X , Ultrassonografia/métodos , Ultrassonografia/normas
10.
Surg Clin North Am ; 81(2): 259-81, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11392416

RESUMO

Pancreatic abnormalities usually are detected on US when it is used for screening patients with abdominal pain and for assessment of the gallbladder and bile ducts. Pancreatic visualization is limited by bowel gas, but with experienced sonographers and newer techniques, including harmonic imaging and oral contrast US, diagnosis of pancreatic abnormalities has significantly improved compared with earlier reports. Appropriate initial diagnosis by US can tailor further investigation, and US-guided biopsy may establish definitive diagnosis.


Assuntos
Pâncreas/diagnóstico por imagem , Pancreatopatias/diagnóstico por imagem , Doença Aguda , Biópsia/métodos , Doença Crônica , Diagnóstico Diferencial , Humanos , Transplante de Pâncreas/diagnóstico por imagem , Pancreatopatias/patologia , Pancreatite/diagnóstico por imagem , Reprodutibilidade dos Testes , Ultrassonografia/métodos
11.
Curr Eye Res ; 6(7): 921-7, 1987 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3621984

RESUMO

This study probed the influence of antigenic exposure on the immunological response of the lacrimal gland. We utilized the germfree rat as a model system to monitor tissue and tear immunoglobulin changes following transfer of these animals into an antigen-laden, conventional environment. The number of IgA- and IgM-containing cells in the lacrimal glands of germfree rats was 5 to 8 fold less than that of conventional controls. This reduced immunological expression in germfree animals also extended to tear IgA levels, which were significantly decreased. No effect of germfree conditions was found on the tear content of secretory component (SC). Transfer of rats from a germfree to a conventional environment resulted in a significant increase in the number of IgA- and IgM-containing cells in the lacrimal gland. By four weeks after 'conventionalization', the number of Ig-containing cells in lacrimal tissue was similar in both ex-germfree and conventional rats. In addition, 'conventionalization' led to a significant increase in the tear content of IgA: within four weeks following exposure to a conventional environment, tear IgA levels in ex-germfree rats were equivalent to those of age-matched, conventional controls. Overall, our results demonstrate that the secretory immune system of the lacrimal gland reacts to antigenic challenge with an increased immunological response.


Assuntos
Aparelho Lacrimal/imunologia , Animais , Formação de Anticorpos , Antígenos/imunologia , Olho/imunologia , Vida Livre de Germes , Sistema Imunitário/metabolismo , Imunoglobulina A/metabolismo , Imunoglobulina G/metabolismo , Aparelho Lacrimal/citologia , Aparelho Lacrimal/metabolismo , Masculino , Ratos , Ratos Endogâmicos , Componente Secretório/metabolismo , Lágrimas/metabolismo
14.
J Virol ; 69(8): 4986-93, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7609069

RESUMO

Poliovirus infection is accompanied by translational control that precludes translation of 5'-capped mRNAs and facilitates translation of the uncapped poliovirus RNA by an internal initiation mechanism. Previous reports have suggested that the capped alfalfa mosaic virus coat protein mRNA (AIMV CP RNA), which contains an unstructured 5' leader sequence, is unusual in being functionally active in extracts prepared from poliovirus-infected HeLa cells (PI-extracts). To identify the cis-acting nucleotide elements permitting selective AIMV CP expression, we tested capped mRNAs containing structured or unstructured 5' leader sequences in addition to an mRNA containing the poliovirus internal ribosome entry site (IRES). Translations were performed with PI-extracts and extracts prepared from mock-infected HeLa cells (MI-extracts). A number of control criteria demonstrated that the HeLa cells were infected by poliovirus and that the extracts were translationally active. The data strongly indicate that translation of RNAs lacking an internal ribosome entry site, including AIMV CP RNA, was severely compromised in PI-extracts, and we find no evidence that the unstructured AIMV CP RNA 5' leader sequence acts in cis to bypass the poliovirus translational control. Nevertheless, cotranslation assays in the MI-extracts demonstrate that mRNAs containing the unstructured AIMV CP RNA 5' untranslated region have a competitive advantage over those containing the rabbit alpha-globin 5' leader. Previous reports of AIMV CP RNA translation in PI-extracts likely describe inefficient expression that can be explained by residual cap-dependent initiation events, where AIMV CP RNA translation is competitive because of a diminished quantitative requirement for initiation factors.


Assuntos
Vírus do Mosaico da Alfafa/genética , Poliovirus/genética , Biossíntese de Proteínas , RNA Mensageiro/genética , RNA Viral/genética , Capsídeo/genética , Células HeLa , Humanos
15.
J Steroid Biochem ; 34(1-6): 253-62, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2696847

RESUMO

The objective of the current investigation was to explore the processes underlying the androgen control of tear IgA and to determine whether hormone exposure also modifies tear IgG content. In addition, studies evaluated the impact of diabetes on the androgen regulation of secretory immunity in the eye. Tears and lacrimal glands were collected from age-matched, adult male rats, which had undergone hypophysectomy, selective ablation of the anterior pituitary, streptozotocin-induced diabetes, sham-surgery and/or orchiectomy and had been exposed to vehicle or physiological amounts of testosterone for varying periods of time. Our findings demonstrated that testosterone administration selectively increased the accumulation of IgA, but not IgG, in tears and lacrimal glands of orchiectomized rats. This hormone effect was associated with a 2-fold enhancement of the IgA transfer from lacrimal tissue to tears; IgA movement was against a gradient. In contrast, androgen exposure had no significant influence on the lacrimal gland/tear transfer of IgG, which was down a 90-fold gradient. Testosterone action on the lacrimal gland appeared to involve an increase in IgA production, but not a consistent alteration in the total number of IgA-containing cells. Similarly, androgen exposure had no impact on the population of IgG-containing lymphocytes in lacrimal tissue. Of interest, ablation of the anterior or entire pituitary in orchiectomized rats, which procedure inhibits testosterone-induced stimulation of tear IgA levels, significantly reduced the total number of IgA-containing cells in the lacrimal gland. Induction of diabetes by streptozotocin injection to orchiectomized rats resulted in diminished tear IgA content and decreased numbers of lacrimal IgA-positive lymphocytes, but did not prevent the testosterone-associated rise in IgA antibody content. In summary, our findings demonstrate that androgens increase the lacrimal gland production and secretion of IgA, but not IgG.


Assuntos
Imunoglobulina A/metabolismo , Imunoglobulina G/metabolismo , Aparelho Lacrimal/imunologia , Animais , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Experimental/fisiopatologia , Ensaio de Imunoadsorção Enzimática , Imunofluorescência , Soros Imunes , Aparelho Lacrimal/efeitos dos fármacos , Aparelho Lacrimal/metabolismo , Masculino , Orquiectomia , Radioimunoensaio , Ratos , Ratos Endogâmicos , Valores de Referência , Testosterona/farmacologia
16.
AJR Am J Roentgenol ; 168(3): 733-6, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9057525

RESUMO

OBJECTIVE: The purpose of the study was to determine if a monophasic waveform with no response to Valsalva's maneuver in the common femoral vein on spectral Doppler sonography is reliable for the diagnosis of proximal venous obstruction. SUBJECTS AND METHODS: In a prospective study from January 1993 through October 1995, 37 of 2138 cancer patients examined with duplex Doppler sonography exhibited monophasic flow in the common femoral vein on spectral Doppler imaging and no response to Valsalva's maneuver. These 37 patients were further evaluated with an abdominal and pelvic CT scan with IV contrast medium (n = 23), with sonography (n = 8), with MR imaging (n = 4), with venography (n = 1), or by both venography and CT (n = 1) to determine the cause of monophasic flow in the common femoral vein and lack of response to Valsalva's maneuver. All follow-up imaging studies were obtained from 0 to 30 days after initial duplex Doppler sonography. RESULTS: All patients with monophasic flow in the common femoral vein on spectral Doppler imaging and no response to Valsalva's maneuver had proximal venous extrinsic compression or deep venous thrombosis. Twenty-nine (78%) of 37 patients had extrinsic compression. Such compression was caused by pelvic masses in 15 (41%) of 37 patients, enlarged nodes in eight patients (22%), and postsurgical changes in six patients (16%). The remaining eight patients (22%) had proximal deep venous thrombosis. CONCLUSION: On spectral Doppler sonography, monophasic waveform with no response to Valsalva's maneuver in the common femoral vein is a dependable sign for the diagnosis of proximal extrinsic compression or deep venous thrombosis. If such a waveform is identified, further investigation is warranted.


Assuntos
Veia Femoral/diagnóstico por imagem , Doenças Vasculares Periféricas/diagnóstico por imagem , Trombose/diagnóstico por imagem , Ultrassonografia Doppler Dupla , Constrição Patológica/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Radiografia , Manobra de Valsalva
17.
Acta Ophthalmol (Copenh) ; 66(1): 87-92, 1988 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3284275

RESUMO

The present study investigated the influence of age and gender on the number of IgA- and IgM-containing cells in the lacrimal gland. Tissues were obtained from male and female rats at 0.2 (infant), 0.6 (pre-pubertal), 1.3 (pubertal), 3 (adult), 8 (mid-life) and 17 (senescent) months of age, then processed for immunofluorescence microscopy. No IgA-containing cells could be detected in lacrimal glands from infant rats, but a significant accumulation had occurred by 0.6 months of age. The extent of this increase was gender-dependent: tissues from male rats had significantly higher IgA-positive cell densities than those of females. After 0.6 months of age, no further variations in the density of IgA-containing lymphocytes were observed in female gland. In contrast, male glands exhibited marked fluctuations in the density of IgA-containing lymphocytes during the time period spanning puberty (0.6----3 months). Of interest, the frequency distribution of IgA-containing cells in tissue sections was not uniform in rats older than 0.2 months. Correction of cell densities for age-related elevations in lacrimal gland weight demonstrated that the total accumulation of IgA-containing cells was both age- and gender-related. Highest cell numbers were attained at 3 months in females and 3 and 17 months in males. Moreover, at all assessed ages, the total IgA-containing cell number in glands of males was greater than, or equal to, that in tissues of females.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Envelhecimento/imunologia , Imunoglobulina A/análise , Imunoglobulina M/análise , Aparelho Lacrimal/imunologia , Animais , Feminino , Imunofluorescência , Masculino , Ratos , Ratos Endogâmicos , Fatores Sexuais
18.
Immunol Invest ; 17(3): 183-94, 1988 May.
Artigo em Inglês | MEDLINE | ID: mdl-3410512

RESUMO

The purpose of the present investigation was to determine the selectivity, specificity and kinetics of the androgen regulation of the ocular secretory immune system. To examine the mucosal selectivity of hormone action, tears, saliva, respiratory and intestinal secretions, urine and serum were collected from orchiectomized rats following four days of treatment with saline or testosterone. Androgen administration significantly increased the tear levels of IgA and free SC. In contrast, this combined hormone response was not duplicated in other mucosal secretions or serum. Consequently, it appears that the androgen control of the ocular secretory immune system is unique to the eye. To evaluate androgenic specificity, orchiectomized rats were treated for four days with saline, testosterone, 5 alpha-androstan-17 beta-o1 ('5 alpha'), 4-estren-7 alpha-methyl-17 beta-o1-3-one ('4-E') or the synthetic analogue, danazol. Results demonstrated that testosterone and '4-E', a potent androgen, both stimulated the accumulation of tear IgA and free SC, compared to amounts in tears of saline-treated controls. The weak androgen '5 alpha' induced a slight rise in tear free SC, but not IgA, levels, whereas danazol had no effect on the ocular secretory immune system. These findings indicate that androgen structure is of critical importance in modulation of mucosal immunity in the eye. Lastly, to assess the kinetics of hormone action on tear IgA and free SC, orchiectomized rats were acutely (0, 1.5, 4, 7, 12, or 24 hours) or chronically (0, 4, 7, 11, 14, or 17 days) exposed to testosterone. Acute androgen exposure for less than 12 hours did not elicit any change in the tear content of IgA or free SC. In comparison, chronic androgen treatment induced a progressive and dramatic rise in the levels of both tear proteins. By 17 days of hormone exposure, the IgA and free SC concentrations in tears had increased by 14- and 18-fold amounts, respectively, relative to amounts in placebo-treated controls. Of interest, the temporal pattern of accumulation of tear IgA and free SC were different. Overall, these results show prolonged, but not abbreviated, exposure to androgens has a profound impact on the IgA and free SC profile in tears.


Assuntos
Androgênios/farmacologia , Olho/efeitos dos fármacos , Animais , Olho/imunologia , Sistema Imunitário/efeitos dos fármacos , Imunoglobulina A Secretora/biossíntese , Masculino , Ratos , Ratos Endogâmicos , Componente Secretório/biossíntese , Lágrimas/efeitos dos fármacos , Lágrimas/imunologia
19.
Radiology ; 215(2): 432-6, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10796921

RESUMO

PURPOSE: To categorize ultrasonographic (US) intratesticular abnormalities in patients after orchiectomy for testicular neoplasm and to correlate US, clinical, and histopathologic findings. MATERIALS AND METHODS: Two hundred thirty-five testicular US examinations were performed in 171 patients who previously underwent orchiectomy for testicular neoplasm. Abnormalities were identified in 28 patients. The abnormalities were described as masses, heterogeneous changes, or macrocalcification. US findings were correlated with histopathologic findings in specimens obtained at surgery in 18 patients; follow-up to determine clinical outcome was obtained from the review of medical records in the remaining 10 patients. RESULTS: Testicular US revealed intratesticular mass in 15, heterogeneous changes in 11, and macrocalcification in two patients. Eighteen patients had histopathologic correlation; 13 had testicular cancer. At US, 10 of the 15 (67%) patients with a mass and only three of the 11 (27%) with heterogeneous changes had cancer. All 10 patients without surgical correlation had clinical follow-up of 2(1/2)-7 years (mean, 3.95 years), with no evidence of disease. CONCLUSION: Intratesticular mass always is a concern, and heterogeneous changes are less worrisome, but in all patients, rigorous follow-up is recommended to rule out malignancy.


Assuntos
Orquiectomia , Neoplasias Testiculares/cirurgia , Testículo/diagnóstico por imagem , Adulto , Biópsia , Calcinose/diagnóstico por imagem , Calcinose/patologia , Distribuição de Qui-Quadrado , Intervalo Livre de Doença , Seguimentos , Germinoma/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/patologia , Estudos Retrospectivos , Seminoma/cirurgia , Doenças Testiculares/diagnóstico por imagem , Doenças Testiculares/patologia , Neoplasias Testiculares/diagnóstico por imagem , Testículo/patologia , Resultado do Tratamento , Ultrassonografia
20.
Pediatr Radiol ; 5(3): 172-4, 1977 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-846767

RESUMO

A case of congenital orbital teratoma is presented with illustrations and discussion of typical radiographic features which may facilitate preoperative diagnosis and treatment.


Assuntos
Doenças do Recém-Nascido/diagnóstico por imagem , Neoplasias Orbitárias/congênito , Teratoma/congênito , Humanos , Recém-Nascido , Masculino , Neoplasias Orbitárias/diagnóstico por imagem , Teratoma/diagnóstico por imagem , Tomografia Computadorizada por Raios X
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