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1.
Med Phys ; 39(6Part13): 3757, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28517320

RESUMO

PURPOSE: Discuss optimised Accelerated Partial Breast Irradiation (APBI) using a Strut-Adjused Volume Implant (SAVI) applicator for patients with implanted pacemeker, without overdosing or relocating the pacemaker. METHODS: A right breast cancer patient with an in situ pacemaker (Medtronic model ADDR01) on the right side underwent breast conservative surgery and was referred for Partial Breast Irradiation (PBI) using Ir-192 High Dose Rate Brachytherapy. Preliminary estimation of the pacemaker dose from a pre-insertion CT study was about 8 % of the prescribed dose which exceeded the generally accepted dose of 2Gy. The challenge was to use a suitable applicator to treat the tumor bed and 1cm margin without exceeding the 2Gy limit to the pacemaker and the leads. A seven catheter SAVI device was selected and implanted in the right breast in an optimal direction and a 3D treatment plan was generated following a post insertion CT scan, using the Oncentra Brachy treatment planning system. Optimization tools namely anatomy based Inverse Planning Simulated Annealing (IPSA), and graphical optimization were utilized to load and optimize the dwell time in the catheters and reduce the dose received by the pacemaker. Device interrogation was conducted before and after the treatment. All operational parameters of the pacemaker were found to be normal.No change in the baseline reference values were observed. RESULTS: Using the SAVI device it was possible to limit the pacemaker/ leads dose to less than 2 Gy. Target V100, V95 and V90 were 90.1%, 95.5% and 98.5% respectively. V150 and V200 being 18.6cc and 10.6cc respectively.Calculated average point doses on pacemaker assembly for ten fractions was 140cGy. CONCLUSIONS: By combining the optimization tools of today's Brachytherapy planning system and a multilumen SAVI applicator, HDR partial breast irradiation can be safely delivered for breast cancer patients with in situ pacemaker, with out the fear of interrupting pacemaker functionality.

2.
Infect Immun ; 69(12): 7729-35, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11705954

RESUMO

We investigated the importance of the host complement system in the pathogenesis of disease mediated by the intramacrophage pathogen Mycobacterium avium. Mycobacteria opsonized with complement are efficiently ingested by macrophages through various complement receptors. Furthermore, unlike other bacteria, mycobacteria can activate both the alternative and classical complement pathways in the absence of specific antibodies. Therefore, to examine the role of complement in the mycobacterial infection process in vivo, mice deficient in complement component C3 were infected with M. avium. Surprisingly, C3-deficient mice infected intravenously with M. avium displayed no difference in bacterial burden or granulomatous response compared to wild-type control mice. C3-sufficient mice and C3-deficient mice were equally susceptible to infection by M. avium regardless of the genotype at the bcg locus, a locus known to confer susceptibility to infection with intracellular pathogens. In vitro studies using mouse bone marrow-derived macrophages resulted in significant M. avium invasion of macrophages in the absence of C3; however, the kinetics of infection were delayed compared to complement-mediated invasion. The data indicate that complement does not play an essential role in mediating M. avium infections in the mouse and suggest either that other invasion mechanisms can compensate for the absence of complement-mediated entry or that complement is not a major mycobacterial opsonin in vivo.


Assuntos
Complemento C3/deficiência , Mycobacterium avium/imunologia , Tuberculose/etiologia , Tuberculose/imunologia , Animais , Anticorpos Antibacterianos , Especificidade de Anticorpos , Células da Medula Óssea/imunologia , Via Alternativa do Complemento , Via Clássica do Complemento , Suscetibilidade a Doenças , Granuloma/etiologia , Fígado/microbiologia , Fígado/patologia , Macrófagos/imunologia , Camundongos , Camundongos Mutantes , Proteínas Opsonizantes , Baço/microbiologia , Fator de Necrose Tumoral alfa/biossíntese
3.
Neurosurgery ; 49(2): 380-9; discussion 390, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11504114

RESUMO

OBJECTIVE: This study analyzed the expression of integrins alpha(v)beta3 and alpha(v)beta5 in glioma tissue and focused on the periphery of high-grade gliomas. METHODS: The analysis was performed with Western blot, immunohistochemistry, and immunofluorescence, by use of two monoclonal antibodies able to recognize the functional integrin heterodimer. The expression of integrin-related ligands and growth factors also was studied. Sections from the tumor periphery were classified as either tumor periphery (light tumor infiltrate or scant visible cells) or peritumor (heavy tumor infiltration). RESULTS: Our data on glioma tissues demonstrated that both integrins were expressed in glioma cells and vasculature and their expression correlated with the histological grade. Alpha(v)beta3 expression was prominent in astrocytic tumors. Both integrins were markers of tumor vasculature, particularly of endothelial proliferation. A high-grade glioma periphery demonstrated a prominent expression of integrin alpha(v)beta3. Cells demonstrating alpha(v)beta3 positivity were identified as tumor astrocytes and endothelial cells by double imaging. The same cells were surrounded by some alpha(v)beta3 ligands and co-localized fibroblast growth factor 2. Matrix metalloproteinase 2 also was found to be co-localized with alpha(v)beta3 in the same cells. Alpha(v)beta3 expression was more relevant in tumor astrocytes. Alpha(v)beta3 integrin and vascular endothelial growth factor expression increased from the periphery to the tumor center. CONCLUSION: Our data support the role of integrins alpha(v)beta3 and alpha(v)beta5 in glioma-associated angiogenesis. In addition, they suggest a role for integrin alpha(v)beta3 in neoangiogenesis and cell migration in high-grade glioma periphery.


Assuntos
Neoplasias Encefálicas/metabolismo , Glioma/metabolismo , Integrinas/metabolismo , Receptores de Vitronectina/metabolismo , Adulto , Idoso , Anticorpos Monoclonais , Vasos Sanguíneos/metabolismo , Western Blotting , Neoplasias Encefálicas/irrigação sanguínea , Neoplasias Encefálicas/patologia , Feminino , Fator 2 de Crescimento de Fibroblastos/metabolismo , Imunofluorescência , Glioma/irrigação sanguínea , Glioma/patologia , Humanos , Imuno-Histoquímica , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Pessoa de Meia-Idade , Distribuição Tecidual , Células Tumorais Cultivadas
4.
Neurosurgery ; 47(5): 1185-95, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11063113

RESUMO

OBJECTIVE: Integrins are emerging as alternative receptors capable of mediating several biological functions, such as cell-matrix and cell-cell adhesion, cell migration, signal transduction, and angiogenesis. Two alpha(v) integrins, i.e., alpha(v)beta3 and alpha(v)beta5, play critical roles in mediating these activities, particularly in tumors. No data are available on the expression of these integrins in meningiomas. METHODS: Using Western blot and immunohistochemical analyses with LM609 and PG32, two monoclonal antibodies capable of recognizing the functional integrin heterodimer, we evaluated the expression of alpha(v)beta3 and alpha(v)beta5 integrins in a series of 34 meningiomas of different histological subtypes and grades. We studied their expression in tumor cells and vasculature, as well as the expression of their related angiogenic factors (fibroblast growth factor 2 and vascular endothelial growth factor) and the alpha(v)beta3 ligand vitronectin. RESULTS: Alpha(v)beta3 and alpha(v)beta5 integrins were expressed by neoplastic vasculature and cells. Alpha(v)beta3 and alpha(v)beta5 expression was associated and correlated with that of their respective growth factors (fibroblast growth factor 2 and vascular endothelial growth factor) and microvessel counts and densities. Alpha(v)beta3 was more strongly expressed than alpha(v)beta5 in two cases of histologically benign meningiomas with aggressive clinical behavior. Alpha(v)beta3 expression was associated with that of its related ligand vitronectin and was also evident in small vessels of brain tissue closely surrounding meningiomas. CONCLUSION: Our data demonstrate the expression of alpha(v)beta3 and alpha(v)beta5 integrins in meningioma cells and vasculature. Our findings suggest a role for both of these integrins, and particularly alpha(v)beta3, in meningioma angiogenesis.


Assuntos
Integrinas/metabolismo , Neoplasias Meníngeas/metabolismo , Meningioma/metabolismo , Adulto , Idoso , Anticorpos Monoclonais , Western Blotting , Movimento Celular/fisiologia , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Matriz Extracelular/metabolismo , Feminino , Fatores de Crescimento de Fibroblastos/metabolismo , Humanos , Imuno-Histoquímica , Masculino , Neoplasias Meníngeas/patologia , Meningioma/patologia , Pessoa de Meia-Idade , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Transdução de Sinais/fisiologia , Células Tumorais Cultivadas , Vitronectina/metabolismo
5.
J Infect Dis ; 182(5): 1304-10, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11023454

RESUMO

The impact of vaccination with plasmid DNA encoding full-length glycoprotein D (gD) from herpes simplex virus (HSV) type 2 (gD2), secreted gD2, or cytosolic gD2 was evaluated in mice and guinea pigs. Immunization with plasmids encoding full-length gD2 or secreted gD2 produced high antibody levels, whereas immunization with DNA encoding cytosolic gD2 resulted in significantly lower antibody titers in both species (P<.001). Vaccination with DNA encoding full-length or secreted gD2 significantly reduced acute disease in mice and guinea pigs (both P<.001) and subsequent recurrent disease in guinea pigs (P<.05). In guinea pigs, immunization with DNA encoding cytosolic gD2 did not protect from acute or recurrent disease, whereas in mice it did protect, but not as well as DNA encoding full-length or secreted gD2. None of the vaccines resulted in improved virus clearance from the inoculation site, and none significantly reduced recurrent disease when used as a therapeutic vaccine in HSV-2-infected guinea pigs.


Assuntos
Plasmídeos , Simplexvirus/imunologia , Vacinas de DNA/imunologia , Proteínas do Envelope Viral/imunologia , Vacinas Virais/imunologia , Animais , Feminino , Cobaias , Imunização , Camundongos , Proteínas do Envelope Viral/genética
6.
Mol Biol Cell ; 10(8): 2619-30, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10436017

RESUMO

The membrane proteins of all regulated secretory organelles (RSOs) recycle after exocytosis. However, the recycling of those membrane proteins that are targeted to both dense core granules (DCGs) and synaptic-like microvesicles (SLMVs) has not been addressed. Since neuroendocrine cells contain both RSOs, and the recycling routes that lead to either organelle overlap, transfer between the two pools of membrane proteins could occur during recycling. We have previously demonstrated that a chimeric protein containing the cytosolic and transmembrane domains of P-selectin coupled to horseradish peroxidase is targeted to both the DCG and the SLMV in PC12 cells. Using this chimera, we have characterized secretagogue-induced traffic in PC12 cells. After stimulation, this chimeric protein traffics from DCGs to the cell surface, internalizes into transferrin receptor (TFnR)-positive endosomes and thence to a population of secretagogue-responsive SLMVs. We therefore find a secretagogue-dependent rise in levels of HRP within SLMVs. In addition, the levels within SLMVs of the endogenous membrane protein, synaptotagmin, as well as a green fluorescent protein-tagged version of vesicle-associated membrane protein (VAMP)/synaptobrevin, also show a secretagogue-dependent increase.


Assuntos
Proteínas de Ligação ao Cálcio , Grânulos Citoplasmáticos/metabolismo , Proteínas de Membrana/metabolismo , Sistemas Neurossecretores/metabolismo , Vesículas Sinápticas/metabolismo , Animais , Transporte Biológico , Carbacol/farmacologia , Membrana Celular/metabolismo , Endossomos/metabolismo , Peroxidase do Rábano Silvestre/genética , Peroxidase do Rábano Silvestre/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Proteínas do Tecido Nervoso/metabolismo , Sistemas Neurossecretores/citologia , Selectina-P/genética , Selectina-P/metabolismo , Células PC12/efeitos dos fármacos , Células PC12/metabolismo , Proteínas R-SNARE , Coelhos , Ratos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Sinaptofisina/efeitos dos fármacos , Sinaptofisina/metabolismo , Sinaptotagminas , Transfecção , Transferrina/metabolismo
7.
J Immunol ; 162(10): 6148-54, 1999 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-10229858

RESUMO

Histoplasma capsulatum (Hc) maintains a phagosomal pH of about 6.5. This strategy allows Hc to obtain iron from transferrin, and minimize the activity of macrophage (Mo) lysosomal hydrolases. To determine the mechanism of pH regulation, we evaluated the function of the vacuolar ATPase (V-ATPase) in RAW264.7 Mo infected with Hc yeast or the nonpathogenic yeast Saccharomyces cerevisae (Sc). Incubation of Hc-infected Mo with bafilomycin, an inhibitor of the V-ATPase, did not affect the intracellular growth of Hc, nor did it affect the intraphagosomal pH. In contrast, upon addition of bafilomycin, phagosomes containing Sc rapidly changed their pH from 5 to 7. Hc-containing phagosomes had 5-fold less V-ATPase than Sc-containing phagosomes as quantified by immunoelectron microscopy. Furthermore, Hc-containing phagosomes inhibited phagolysosomal fusion as quantified by the presence of acid phosphatase, accumulation of LAMP2, and fusion with rhodamine B-isothiocyanate-labeled dextran-loaded lysosomes. Finally, in Hc-containing phagosomes, uptake of ferritin was equivalent to phagosomes containing Sc, indicating that Hc-containing phagosomes have full access to the early "bulk flow" endocytic pathway. Thus, Hc yeasts inhibit phagolysosomal fusion, inhibit accumulation of the V-ATPase in the phagosome, and actively acidify the phagosomal pH to 6.5 as part of their strategy to survive in Mo phagosomes.


Assuntos
Histoplasma/imunologia , Macrófagos/imunologia , Fusão de Membrana , Organelas/enzimologia , ATPases Translocadoras de Prótons/biossíntese , ATPases Vacuolares Próton-Translocadoras , Animais , Lisossomos/enzimologia , Lisossomos/microbiologia , Macrófagos/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Organelas/microbiologia , Fagossomos/enzimologia , Fagossomos/microbiologia
8.
Cancer Res ; 58(20): 4654-9, 1998 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-9788618

RESUMO

Human malignant gliomas are among the most malignant and most intensely vascularized solid tumors. Angiostatin, an internal fragment of plasminogen, was recently discovered as an endogenous inhibitor of tumor-related angiogenesis by selective inhibition of endothelial cell growth. Using xenograft transplants of rat and primary human glioma cells in immunodeficient mice we investigated the effects of systemic administration of angiostatin purified from human plasma on tumor growth. The rat C6 and 9L glioma and the human U87 glioma cell lines implanted either s.c. or intracranially in Swiss nude mice responded to angiostatin in a dose-dependent fashion with growth inhibition to 11% of controls (P < 0.01), without detectable signs of toxicity. The inhibition of treated tumors was accompanied by a marked reduction of vascularity to 38% of controls (P < 0.01) in the presence of an up to 6-fold increased apoptotic index (P < 0.01), consistent with the hypothesis that angiostatin acts tumoristatic by inhibiting tumor-induced endothelial cell proliferation. Expression analysis of growth factors in angiostatin-treated tumors revealed an up to 3-fold decrease in vascular endothelial growth factor-mRNA and an up to 4-fold increase in basic fibroblast growth factor-mRNA, as compared with untreated controls in rat gliomas (P < 0.01). This suggests that inhibition of the tumorigenic phenotype may be mediated in part by a downregulation of vascular endothelial growth factor expression within the tumor. Our data demonstrate that systemic administration of angiostatin efficiently suppresses malignant glioma growth in vivo. The tumoristatic activity against intracranial tumors independent of the blood brain barrier suggests that targeting the vascular compartment may offer novel therapeutic strategies against malignant gliomas.


Assuntos
Antineoplásicos/uso terapêutico , Glioma/tratamento farmacológico , Fragmentos de Peptídeos/uso terapêutico , Plasminogênio/uso terapêutico , Angiostatinas , Animais , Apoptose/efeitos dos fármacos , Fatores de Crescimento Endotelial/genética , Glioma/irrigação sanguínea , Glioma/patologia , Humanos , Linfocinas/genética , Masculino , Camundongos , Transplante de Neoplasias , Neovascularização Patológica/prevenção & controle , Ratos , Transplante Heterólogo , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
9.
Arterioscler Thromb Vasc Biol ; 18(2): 272-6, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9484993

RESUMO

Peroxisome proliferator-activated receptors (PPARs) and retinoid X receptors (RXRs) are members of the intracellular receptor superfamily. PPARs bind to peroxisome proliferator-response elements (PPREs) as heterodimers with RXR and as such activate gene transcription in response to activators. Fibrates like gemfibrozil are well-known PPARalpha activators and are used in the treatment of hyperlipidemia. We show that the RXR ligand LGD1069 (Targretin), like gemfibrozil, can activate the PPARalpha/RXR signal-transduction pathway, including transactivation of the bifunctional enzyme or acyl-CoA oxidase response elements in a cotransfection assay. The activation also occurs in vivo, whereby in rats treated with LGD1069 or gemfibrozil, bifunctional enzyme and acyl-CoA oxidase RNA are induced and the combination of LGD1069 and gemfibrozil leads to a greater induction. Importantly, in hypertriglyceridemic db/db mice treated with RXR or PPARalpha agonists, triglyceride levels are lowered, and the combination again has significantly greater efficacy. RXR agonists also raise HDL cholesterol levels without changing apoA-I RNA expression. This observation suggests the use of RXR-selective agonists, "rexinoids," either alone or in combination with a fibrate as a new therapeutic approach to treating patients with high triglyceride and low HDL cholesterol levels.


Assuntos
HDL-Colesterol/sangue , Regulação da Expressão Gênica/fisiologia , Receptores Citoplasmáticos e Nucleares/fisiologia , Receptores do Ácido Retinoico/agonistas , Fatores de Transcrição/agonistas , Fatores de Transcrição/fisiologia , Triglicerídeos/sangue , Acil-CoA Oxidase , Animais , Bexaroteno , Combinação de Medicamentos , Feminino , Genfibrozila/farmacologia , Hipertrigliceridemia/sangue , Hipertrigliceridemia/genética , Hipolipemiantes/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Oxirredutases/genética , Ratos , Ratos Sprague-Dawley , Receptores X de Retinoides , Transdução de Sinais/efeitos dos fármacos , Tetra-Hidronaftalenos/farmacologia , Ativação Transcricional/genética
11.
J Pharmacol Exp Ther ; 275(3): 1647-55, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8531140

RESUMO

Intracranial tumors, such as glioblastoma multiforme and astrocytomas, are among the most aggressive and difficult to cure. In the present study, we evaluated the intracranial distribution of released agents during the first 3 days after implantation. Polymer implants containing [3H]-1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU), [3H]dextran (MW 70,000) or [14C]iodoantipyrene (IAP) were implanted into the brains of rabbits; autoradiography was used to measure the distribution of radiolabels within the brain at 6, 24 and 72 hr after implantation. For all of the agents studied, the majority of the radioactivity was found within the region 1 to 2 mm from the surface of the polymer. Dextran, however, penetrated farther into the brain than either IAP or BCNU. The distribution of radiolabel on an anteroposterior axis was determined by examining serial coronal images: after 72 hr, significant radioactivity (< 2 S.D. above background) extended > 17 mm in animals with [3H]dextran implants and approximately mm in animals receiving [3H]BCNU or [14C]IAP. Concentration profiles were also measured on coronal images obtained at the implant site: radioactivity dropped to a 10% maximum value 1.7 mm from the surface of the pellet in [3H]dextran-treated animals and < 1.2 mm in [3H]BCNU or [14C]IAP-treated animals. Measured concentration profiles near the polymer were compared to mathematical models of drug diffusion and elimination. These results demonstrate that the majority of agents delivered into the brain by intracranially implanted polymers accumulates in the tissue within 1 to 2 mm of the implant, but that the size of the treated region depends on physicochemical properties of the agents.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Encéfalo/metabolismo , Carmustina/farmacocinética , Animais , Antipirina/análogos & derivados , Antipirina/farmacocinética , Autorradiografia , Biodegradação Ambiental , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Carmustina/administração & dosagem , Carmustina/uso terapêutico , Implantes de Medicamento , Masculino , Polímeros , Coelhos
12.
J Neurooncol ; 26(2): 91-102, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8787851

RESUMO

Intracranial controlled release polymers have been used for drug delivery to the brain, bypassing the blood brain barrier (BBB). By understanding the rates and patterns of transport in the local tissues, it is possible to design delivery systems that provide the optimal spatial and temporal pattern of chemotherapy within the intracranial space. This paper reviews the kinetics of drug release from polymeric controlled release implants, and describes the fate of drug molecules following release into the brain interstitium. Potential improvements in drug delivery based on the understanding of the mechanisms of drug release, transport and elimination are discussed.


Assuntos
Antineoplásicos/administração & dosagem , Antineoplásicos/farmacocinética , Encéfalo/metabolismo , Animais , Implantes de Medicamento , Humanos
14.
AAOHN J ; 42(7): 325-8, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8060396

RESUMO

1. Community health nurses address a wide variety of environmental issues, including problems with air and water quality, hazardous waste, and pesticide exposure. 2. Many community health nurses do not feel competent in identifying resources among health professionals and regulatory agencies to address environmental health issues. 3. Most community health nurses (79%) are interested in learning more about environmental health issues, with continuing education as the preferred format. 4. Major conceptual areas of occupational health and environmental health overlap, and qualified occupational health nurses may serve as resources in these particular areas.


Assuntos
Enfermagem em Saúde Comunitária/educação , Saúde Ambiental , Saúde Ocupacional , Competência Clínica , Currículo , Humanos , Inquéritos e Questionários
15.
Clin Exp Immunol ; 95(2): 337-42, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8306510

RESUMO

In addition to its activity as a metabolic hormone and a regulator of somatic growth, insulin-like growth factor-I (IGF-I) has cytokine-like activities on lymphoid cells. A 14-day infusion of recombinant human (rh)IGF-I increased lymphocyte numbers in all the peripheral lymphoid organs examined. This increase was apparent for up to 3 weeks following cessation of hormone treatment. A second administration of rhIGF-I, given when the lymphocyte numbers in the rhIGF-I-treated mice had returned to control values, resulted in similar increases in the peripheral T and B cell populations. This increase in lymphocyte numbers had functional significance, since rhIGF-I-treated mice produced elevated antibody titres following primary or secondary antigen challenge compared with controls. In addition, when rhIGF-I-treated mice were immunized with a suboptimal dose of antigen they produced antibody titres which were equivalent to those generated by immunization with optimal doses of antigen. When examined in vitro, addition of rhIGF-I alone to cultures of splenocytes from antigen-primed mice stimulated immunoglobulin synthesis. These studies suggest that IGF-I produced locally by thymic and bone marrow stromal cells may be a natural component of B and T cell lymphopoiesis.


Assuntos
Imunoglobulinas/biossíntese , Fator de Crescimento Insulin-Like I/farmacologia , Animais , Antígenos/imunologia , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Peso Corporal/efeitos dos fármacos , Imunofenotipagem , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Tamanho do Órgão/efeitos dos fármacos , Proteínas Recombinantes/farmacologia
16.
FEBS Lett ; 338(1): 16-22, 1994 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-8307150

RESUMO

Using oligonucleotide primers derived from the vesicular monoamine transporters sequences, a cDNA predicted to encode the bovine chromaffin granule amine transporter has been cloned (b-VMAT2). Surprisingly, its structure is more similar to the rat brain transporter (VMAT2), than to the rat adrenal counterpart (VMAT1). Unlike rat VMAT1, bovine VMAT2 appears to be expressed both in the adrenal medulla and the brain, as judged by Northern analysis. After modification/deletion of the seven amino acids at the N-terminus of the protein it was expressed in a functional form. The order of affinity of the bovine VMAT2 transporter to substrates is: serotonin > dopamine = norepinephrine > epinephrine. Also, the recombinant bovine adrenal transporter is highly sensitive to tetrabenazine, in sharp contrast to the rat adrenal transporter. The findings indicate, therefore, a clear species variation in which structure and function of the bovine adrenal transporter resemble the rat brain protein, while its tissue distribution is distinct from both types of rat proteins. In addition, the predicted protein sequence is identical to the experimentally determined N-terminus sequence of the purified vesicular amine transporter [Stern-Bach et al. (1992) Proc. Natl. Acad. Sci. USA 89, 9730-9733].


Assuntos
Monoaminas Biogênicas/metabolismo , Grânulos Cromafim/metabolismo , Glicoproteínas/genética , Glicoproteínas de Membrana , Proteínas de Membrana Transportadoras , Neuropeptídeos , Tetrabenazina/farmacologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Transporte Biológico , Catálise , Bovinos , Grânulos Cromafim/efeitos dos fármacos , Clonagem Molecular , DNA Complementar , Dados de Sequência Molecular , RNA Mensageiro/metabolismo , Homologia de Sequência de Aminoácidos , Proteínas Vesiculares de Transporte de Aminas Biogênicas , Proteínas Vesiculares de Transporte de Monoamina
17.
J Clin Invest ; 92(2): 540-8, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8349796

RESUMO

We show that treatment of adult mice with recombinant human insulin-like growth factor 1 (rhIGF-1) induces striking modifications in lymphocyte number and function. 9-mo-old male mice received rhIGF-1 (4 mg/kg per d) or its excipient by subcutaneous infusion from osmotic minipumps for 7 or 14 d. Mice were weighed daily and bled at sacrifice; the spleen and thymus were harvested and single cell suspensions were made for analysis of cell phenotype and cell number. The responses of splenocytes to mitogens (concanavalin A, lipopolysaccharide, and pokeweed mitogen), alloantigens and dinitrophenyl ovalbumin were measured. After either 7 or 14 d of treatment, rhIGF-1 had an overall whole-body anabolic effect, resulting in increased body and organ weights with prominent increases in the weight of the spleen and thymus. Furthermore, the rhIGF-1 treated mice were normoglycemic but had reduced blood urea nitrogens, again reflecting the anabolic activity of rhIGF-1. The increased spleen and thymus weights were associated with a large increase in the number of lymphocytes in both organs. In addition to an increase in T cells, specifically CD4+ T cells, a dramatic increase in splenic B cells was also observed. This increase was accompanied by an enhanced responsiveness to dinitrophenyl ovalbumin resulting in increased immunoglobulin production. However, despite the increases in cellularity, there was a decrease in the in vitro responses of spleen cells to mitogens after 7 d of rhIGF-1 treatment. In contrast, treatment with rhIGF-1 for 14 d increased both the cell number and mitogenic responses of splenocytes suggesting that some time is required for the cells populating the peripheral organs to gain mitogenic responsiveness. It is clear from these data that rhIGF-1, at doses that have whole-body anabolic activity, can expand cell number in lymphoid tissue in a normal adult mouse. These dual effects of rhIGF-1, of increasing lymphocyte number and activity, indicate that, in a normal adult animal, rhIGF-1 can cause major changes in lymphoid tissues that are of potential benefit to the functioning of the immune system.


Assuntos
Fator de Crescimento Insulin-Like I/farmacologia , Ativação Linfocitária , Linfócitos/efeitos dos fármacos , Animais , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoglobulina G/análise , Imunoglobulina G/biossíntese , Infusões Parenterais , Fator de Crescimento Insulin-Like I/administração & dosagem , Teste de Cultura Mista de Linfócitos , Linfócitos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Mitógenos , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/farmacologia , Baço/efeitos dos fármacos , Baço/imunologia , Subpopulações de Linfócitos T/efeitos dos fármacos , Subpopulações de Linfócitos T/imunologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Timo/efeitos dos fármacos , Timo/imunologia , Fatores de Tempo
18.
J Appl Toxicol ; 13(4): 291-6, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8376730

RESUMO

2,2,4-Trimethylpentane (TMP), a nephrotoxic component of unleaded gasoline in male but not female rats, undergoes oxidative metabolism to yield 2,2,4- and 2,4,4-trimethylpentanol, pentanoic acid and 5-hydroxypentanoic acid. We have examined the effect of three of these pentanoic acid metabolites on the renal transport of the organic anion p-aminohippurate (PAH) and the organic cation tetraethylammonium (TEA) in renal cortical slices from male Fischer 344 rats. 2,4,4-Trimethylpentanoic acid, the major urinary metabolite in rats, produced a selective decrease in the accumulation of PAH without affecting TEA accumulation. Kinetic analysis showed that 2,4,4-trimethylpentanoic acid was a competitive inhibitor of the organic anion transport system, with a Ki of 4 mM. 2,4,4-Trimethyl-5-hydroxypentanoic acid also showed selective inhibition of PAH transport, while 2,2,4-trimethylpentanoic acid was less selective and reduced both PAH and TEA transport. Additional studies with radiolabeled 2,4,4-trimethylpentanoic acid showed that there was a time- and concentration-dependent accumulation of radioactivity into slices of renal cortex. However, experiments conducted at 4 degrees C and studies with metabolic inhibitors, or with an inhibitor of organic anion transport, indicated that little of the accumulated material was entering the cell. We conclude from these studies that the pentanoic acid metabolites formed from 2,2,4-trimethylpentane are not actively transported by the renal organic anion transport system. In summary, in vitro the pentanoic acid metabolites appear to bind to renal cortical tissue and thereby reduce the transport of PAH.


Assuntos
Córtex Renal/metabolismo , Octanos/metabolismo , Compostos de Tetraetilamônio/farmacocinética , Ácido p-Aminoipúrico/farmacocinética , Animais , Transporte Biológico/efeitos dos fármacos , Córtex Renal/efeitos dos fármacos , Masculino , Octanos/toxicidade , Ratos , Ratos Endogâmicos F344
19.
Ultraschall Med ; 13(1): 24-7, 1992 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-1585156

RESUMO

In patients with cervical incompetence, the diagnostic efficiency of abdominal, perineal and vaginal sonography was compared. 73 patients, who were divided into three groups, were examined: Group A (n = 50) control group, Group B (n = 11) normal pregnancies, Group C (n = 12) pregnancies with demonstrated cervical incompetence. According to our results, using vaginal sonography, only the incompetent pregnancies showed significant shortening of the cervical length. Characteristic scans were also obtained (membrane herniation) which were useful in diagnosis and control in the performance of cerclage.


Assuntos
Colo do Útero/diagnóstico por imagem , Ultrassonografia Pré-Natal/instrumentação , Incompetência do Colo do Útero/diagnóstico por imagem , Aborto Habitual/diagnóstico por imagem , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Gravidez , Valores de Referência , Fatores de Risco
20.
Eval Health Prof ; 15(1): 115-27, 1992 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10183639

RESUMO

Subjects were 180 registered nurses enrolled in a master's nursing program. By random assignment, each read one of six versions of a vignette about a male patient. Vignettes differed in terms of patient's diagnosis (AIDS of unspecified origin, AIDS in a hemophiliac infected by blood transfusion, and leukemia) and sexual preference (gay or heterosexual). Nurses evaluated the patient on two scales, one involving judgments of patients and the other concerning willingness to interact socially with them. The hemophiliac/AIDS and leukemia patients were judged significantly less responsible for and less deserving of their illnesses than was the patient with AIDS of unspecified origin (p less than .001). However, all three diagnostic categories were considered equally deserving of the best possible care. Both categories of AIDS patients were stigmatized in terms of certain social interactions. There was also some weak evidence of antigay bias. Implications for theory and practice are discussed.


Assuntos
Síndrome da Imunodeficiência Adquirida/psicologia , Atitude do Pessoal de Saúde , Relações Enfermeiro-Paciente , Estudantes de Enfermagem/psicologia , Síndrome da Imunodeficiência Adquirida/etiologia , Adulto , Coleta de Dados , Feminino , Hemofilia A , Homossexualidade , Humanos , Leucemia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudantes de Enfermagem/estatística & dados numéricos , Estados Unidos
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