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1.
J Acoust Soc Am ; 155(2): R3-R4, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38341726

RESUMO

The Reflections series takes a look back on historical articles from The Journal of the Acoustical Society of America that have had a significant impact on the science and practice of acoustics.

2.
Osteoarthritis Cartilage ; 23 Suppl 1: S22-42, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25527217

RESUMO

Monoclonal antibodies that bind and inhibit nerve growth factor (NGF) have demonstrated both, good analgesic efficacy and improvement in function in patients with osteoarthritis (OA). Despite initial promising data, trials in OA had been suspended by the Federal Food and Drug Administration (FDA) due to concerns over accelerated rates of OA progression. Imaging will play a crucial role in future clinical trials to define eligibility of potential participants and to monitor safety during the course of these studies. This will require baseline and frequent follow-up radiographs of both, the index joints and other large weight bearing joints to identify subjects at risk prior inclusion and on study so treatment can be discontinued. This imaging overview in the form of an atlas describes and illustrates potential exclusionary joint imaging findings at eligibility and potential adverse joint events on radiography and magnetic resonance imaging (MRI) in studies investigating a-NGF compounds. The overarching goal of this atlas is to facilitate trial design and to promote a common language and understanding between potential expert readers. This first section of the atlas will focus on knee joint specific findings that are relevant to a-NGF studies.


Assuntos
Anticorpos Monoclonais/efeitos adversos , Artropatias/induzido quimicamente , Artropatias/diagnóstico , Articulação do Joelho , Fator de Crescimento Neural/antagonistas & inibidores , Anticorpos Monoclonais/uso terapêutico , Atlas como Assunto , Diagnóstico por Imagem , Humanos , Osteoartrite/tratamento farmacológico
3.
Osteoarthritis Cartilage ; 23 Suppl 1: S43-58, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25527219

RESUMO

Recently, nerve growth factor (NGF) inhibitors have been introduced for treatment of osteoarthritis (OA) symptoms, and have shown good analgesic efficacy and improvement in function in patients with OA. However, anti- (a-)NGF trials in OA had been suspended by the U.S. Food and Drug Administration (FDA) due to concerns over accelerated rates of OA progression and osteonecrosis. Since a-NGF therapies offer potential as the first new class of analgesics for many years, future studies assessing a-NGF compounds will have to follow stringent eligibility criteria and will require a rigorous safety monitoring. Imaging is paramount to identify potential negative outcomes as early as possible. These imaging findings include atrophic OA, osteonecrosis and others at eligibility and especially rapid progressive OA (RPOA) during the course of treatment. This second part of the a-NGF imaging atlas will present specific hip joint imaging findings that are relevant for eligibility and safety and represent potential adverse joint events on radiography and magnetic resonance imaging (MRI) in studies investigating a-NGF compounds. Researchers and clinicians should become familiar with several of these entities, and especially osteonecrosis of the hip and insufficiency fractures are relatively common findings in such a patient population. As several of these diagnoses may only be detected at late stages using radiographic methods, MRI plays an important role in identifying such pathologies early and at potentially still reversible stages before irreversible joint destruction has occurred.


Assuntos
Anticorpos Monoclonais/efeitos adversos , Articulação do Quadril , Artropatias/induzido quimicamente , Artropatias/diagnóstico , Fator de Crescimento Neural/antagonistas & inibidores , Anticorpos Monoclonais/uso terapêutico , Atlas como Assunto , Diagnóstico por Imagem , Humanos , Osteoartrite/tratamento farmacológico
4.
Osteoarthritis Cartilage ; 23 Suppl 1: S59-68, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25527220

RESUMO

Despite promising results, the U.S. Food and Drug Administration (FDA) put on hold trials assessing anti-nerve growth factor (a-NGF) compounds due to concerns over accelerated rates of OA progression. The mechanism of these events is unclear but joint adverse events were observed particularly in patients using a-NGFs in combination with non-steroidal anti-inflammatory drugs (NSAIDs), suggesting that the significantly greater analgesic effect of these separate classes of drugs prompted patients to permit increased joint load without experiencing the usual pain that would limit joint stress. Development of a-NGF drugs is continuing with stringent safety criteria included in future trials as a-NGF therapies offer potential as the first new class of analgesics in many years. Potential imaging joint safety findings and exclusionary criteria for eligibility for the large weight bearing joints were presented in parts I and II of this atlas. The shoulder as a non-weight bearing joint is likely to be less affected by increased loading due to efficacious pain reduction. However, it remains prone to degeneration especially due to concomitant rotator cuff pathology and previous trauma and inflammatory disorders. This third part of the atlas illustrates imaging findings relevant for eligibility and potential joint safety findings such as osteonecrosis, incidental findings such as large cystic lesions, inflammatory disorders, bone marrow disorders and metastases.


Assuntos
Anticorpos Monoclonais/efeitos adversos , Artropatias/induzido quimicamente , Artropatias/diagnóstico , Fator de Crescimento Neural/antagonistas & inibidores , Articulação do Ombro , Anticorpos Monoclonais/uso terapêutico , Atlas como Assunto , Diagnóstico por Imagem , Humanos , Osteoartrite/tratamento farmacológico
5.
Osteoporos Int ; 26(10): 2441-7, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25956286

RESUMO

UNLABELLED: This study compared the effects of pediatric acne treatment with two isotretinoin formulations on bone mineral density. We demonstrated no difference in the effect of the two formulations. No effect on pediatric bone mineral density was identified for either formulation. INTRODUCTION: Isotretinoin (13-cis-retinoic acid) is a treatment for recalcitrant nodular acne with a purported effect on bone mineral density (BMD). The side effects of isotretinoin on vertebral bone were evaluated to assess the safety of a new FDA-approved isotretinoin formulation: Lidose-isotretinoin (Cip-Iso). METHODS: This double-blind, randomized, phase III, active control, parallel-group, multicenter study compared the safety, efficacy, and non-inferiority of CIP-Iso to a marketed reference product, Accutane®, in severe recalcitrant nodular acne subjects. Three hundred fifty-eight pediatric male and female subjects aged between 12 and 17 years underwent 20 weeks of treatment with PA lumbar spine dual X-ray absorptiometry (DXA) measurements obtained for bone mineral density (BMD) and Z-scores, 5.5 months apart on visits 1 and 8. One hundred sixty-eight of 358 subjects had height adjusted Z-scores (HAZ) calculated. RESULTS: There was no difference in the least squares (LS) mean Z-score or HAZ of the two drugs at visit 1 or 8. The mean and LS mean Z-score and HAZ were greater than zero at visits 1 and 8 for both drugs. The change in the LS mean spine Z-score, but not HAZ, between visits, was statistically significant for both drugs. There was a mean increase in BMD (g/cm(2)) for both products between visits. CONCLUSIONS: There is no difference in the effect of two formulations of isotretinoin on spine bone density after 6 months of treatment. BMD increased and the small change in spine Z-score over treatment disappeared after height adjustment. Mean positive Z-scores and HAZ in the study were likely due to the exclusion of low and inclusion of high Z-score subjects.


Assuntos
Densidade Óssea/efeitos dos fármacos , Fármacos Dermatológicos/farmacologia , Isotretinoína/farmacologia , Absorciometria de Fóton/métodos , Acne Vulgar/tratamento farmacológico , Adolescente , Química Farmacêutica , Criança , Fármacos Dermatológicos/efeitos adversos , Fármacos Dermatológicos/uso terapêutico , Método Duplo-Cego , Feminino , Humanos , Isotretinoína/efeitos adversos , Isotretinoína/uso terapêutico , Vértebras Lombares/fisiopatologia , Masculino
6.
Curr Opin Cell Biol ; 12(2): 229-34, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10712924

RESUMO

Protein 4.1 (also called band 4.1 or simply 4.1) was originally identified as an abundant protein of the human erythrocyte, in which it stabilizes the spectrin/actin cytoskeleton. The protein and its relatives have since been found in many cell types of metazoan organisms and they are often concentrated in the nucleus, as well as in cell-cell junctions. They form multimolecular complexes with transmembrane and membrane-associated proteins, and these complexes may be important for both structural stability and signal transduction at sites of cell contact.


Assuntos
Proteínas do Citoesqueleto , Citoesqueleto/fisiologia , Membrana Eritrocítica/fisiologia , Proteínas de Membrana/genética , Neuropeptídeos , Animais , Guanilato Quinases , Humanos , Proteínas de Membrana/metabolismo , Proteínas de Membrana/fisiologia , Núcleosídeo-Fosfato Quinase/metabolismo
7.
Environ Entomol ; 50(6): 1490-1504, 2021 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-34555164

RESUMO

The spotted lanternfly, Lycorma delicatula (Hemiptera: Fulgoridae) (White, 1845), is an invasive pest in the Mid-Atlantic region of the United States. Understanding this pest's dispersion patterns is fundamental for development of management and surveillance programs. To address this knowledge gap, we quantified spotted lanternfly nymph dispersion patterns by instar for rural and urban/suburban habitats, and we compared the number of sample units required for sticky traps and in situ visual counts to estimate population densities at several precisions. In addition, we assessed the ability of two experimental designs (completely random and randomized complete block) to detect management practices' impacts in the field. All instars typically followed an aggregated dispersion pattern. Sample size and time requirements for checking and replacing sticky traps and for conducting in situ counts were similar, but in situ counts do not require purchasing traps, installation time, or delays before treatment, and do not remove insects. Although the cost for using in situ counts is likely less than for sticky traps, early instar spotted lanternfly nymph populations are harder to visually detect than later instars because of their small size, which may negate any cost advantage when treatments are applied early. In general, using a randomized complete block design resulted in higher statistical power than a completely random design, allowing detection of proportional population reductions of 10-20% less with equal replication. Studies aiming to evaluate treatments that reduce spotted lanternfly numbers by less than 60% will require researchers to evaluate the feasibility of using the required large sample sizes.


Assuntos
Hemípteros , Animais , Insetos , Ninfa , Densidade Demográfica , Projetos de Pesquisa
8.
Environ Entomol ; 49(6): 1462-1472, 2020 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-33315076

RESUMO

The spotted lanternfly, Lycorma delicatula (White), is a new invasive pest in the United States. To quantify spotted lanternfly population abundance, one must understand this pest's dispersion pattern, that is, the spatial arrangement of individuals within a population. Spotted lanternflies overwinter in egg masses from late fall to May, making this life stage suitable for population assessments. We measured the dispersion pattern of egg masses at two types of sites: a suburban housing development, where we used individual trees as the sampling unit, and rural woodlots, where we used individual trees and also plots with 5.64 m radius as sampling units. Plots were the same size as those recommended for monitoring the gypsy moth, a well-studied pest with similar egg laying habit to the spotted lanternfly. Egg masses in both sampling units were counted up to a height of 3 m. With trees as the sampling unit, egg masses were aggregated in 12 of 20 rural sampling universes, randomly dispersed at 6, and completely absent at 2. Similar patterns were seen when using the 5.64-m radius rural sampling units and for suburban sampling universes. We calculated sample size requirements for a range of mean densities at a precision of 25 and 30%. Additionally, the vertical distribution of egg masses was characterized on the invasive tree of heaven [Ailanthus altissima (Mill.) Swingle], a preferred host for spotted lanternflies. For small trees, there was a positive relationship between number of egg masses in the bottom 3 m of the tree and the total count.


Assuntos
Ailanthus , Hemípteros , Animais , Oviposição , Tamanho da Amostra , Árvores
9.
Res Vet Sci ; 114: 74-79, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28319830

RESUMO

Metformin is an oral hypoglycemic drug that has been shown to inhibit cancer cell proliferation via up-regulation of AMPK (AMP-activated protein kinase), and possibly inhibition of mTOR (mammalian target of rapamycin). The purpose of this study was to evaluate the effects of metformin on a feline injection site sarcoma cell line. Cells from a feline injection site sarcoma cell line were treated with metformin at varied concentrations. A dose-dependent decrease in cell viability following metformin treatment was observed, with an IC50 of 8.0mM. Using flow cytometry, the mechanism of cell death was determined to be apoptosis or necrosis. To evaluate the role of mTOR inhibition in metformin-induced cell death, Western blot was performed. No inhibition of mTOR or phosphorylated mTOR was found. Although metformin treatment leads to apoptotic or necrotic cell death in feline injection site sarcoma cells, the mechanism does not appear to be mediated by mTOR inhibition.


Assuntos
Doenças do Gato/tratamento farmacológico , Sobrevivência Celular/efeitos dos fármacos , Hipoglicemiantes/farmacologia , Metformina/farmacologia , Sarcoma/veterinária , Animais , Apoptose/efeitos dos fármacos , Doenças do Gato/etiologia , Gatos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Concentração Inibidora 50 , Injeções/efeitos adversos , Injeções/veterinária , Sarcoma/patologia , Serina-Treonina Quinases TOR/antagonistas & inibidores
10.
J Natl Cancer Inst ; 65(5): 937-48, 1980 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6933264

RESUMO

A comparison was made of the histologic characteristics of naturally occurring and Nitrofen-induced liver tumors in (C57BL/6 X C3H)F1 (B6C3F1) mice. Whereas induced tumors generally consisted of solid sheets or nodules of frequently enlarged eosinophilic hepatocytes containing enlarged and/or hyperchromatic nuclei, the spontaneous neoplasms consisted predominantly of small basophilic cells containing oval or round nuclei and frequently arranged in trabeculae 1--2 cells wide. Within the livers of Nitrofen-treated animals, foci of hepatocytes resembling those within the tumor masses were also observed in the nonneoplastic areas. Metastases were not present in the lungs of any controls, whereas small emboli or large masses of neoplastic hepatocytes were present in incidences up to 29% in treated mice with tumors. This bioassay provides evidence that, in some cases, liver tumors in treated mice are morphologically different from those in controls and suggests that Nitrofen induces unique liver tumors rather than acts as a promoter of spontaneous neoplasms.


Assuntos
Neoplasias Hepáticas Experimentais/patologia , Éteres Fenílicos , Animais , Feminino , Fígado/patologia , Neoplasias Hepáticas Experimentais/induzido quimicamente , Masculino , Camundongos , Camundongos Endogâmicos
11.
J Natl Cancer Inst ; 73(6): 1327-36, 1984 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6595443

RESUMO

The potential promoting and/or complete carcinogenic activity of a methyl group-deficient (MD) diet lacking methionine, choline, vitamin B12, and folate on liver tumor induction in weanling male F344/NCr rats was examined. Each of 50 rats per group received one injection 20 mg diethylnitrosamine [(DENA) CAS: 55-18-5; N-nitrosodiethylamine]/kg body weight at 4 weeks of age, and then each was maintained on a methyl group-adequate (MA) diet for 52 weeks (groups 2 and 5) or on an MD diet for 15 weeks followed by the MA diet for 37 weeks (group 4). Controls received injections of saline and were maintained on the same two respective diet regimens (groups 1 and 3, respectively). Histologic results from sacrifices at 6, 10, 15, 22, 39, and 52 weeks revealed early development of foci of eosinophilic gamma-glutamyltransferase (GGT)-positive hepatocytes by week 6 in DENA-MD diet-treated rats, with subsequent development of a diffuse hyperplasia of hepatocytes, oval cell proliferation, cholangiofibrosis, nodular cirrhosis, and neoplastic nodule (NN) formation and, at 52 weeks, hepatocellular carcinomas (HCC) in 13 of 15 rats. Similar but significantly fewer lesions were observed at slightly later sacrifice times in the livers of saline-MD diet-treated rats, with development of NN in 5 of 12 rats and an HCC in 1 of 12 rats at 52 weeks. DENA-treated rats on MA diets developed relatively few GGT-positive foci, and none developed any neoplastic lesions. Except for basophilic foci, areas and foci of cellular alteration containing glycogen-rich hepatocytes frequently exhibited diminished uptake of injected iron and decreased glucose-6-phosphatase and ATPase contents focally or throughout. This study indicates that a relatively brief exposure of both untreated and DENA-treated weanling rats to a severely MD diet produces classical preneoplastic and neoplastic lesions in their livers.


Assuntos
Colina/toxicidade , Dietilnitrosamina/toxicidade , Deficiência de Ácido Fólico/patologia , Neoplasias Hepáticas Experimentais/patologia , Fígado/patologia , Metionina/toxicidade , Nitrosaminas/toxicidade , Vitamina B 12/toxicidade , Animais , Peso Corporal , Dieta , Sinergismo Farmacológico , Fígado/efeitos dos fármacos , Masculino , Ratos , Ratos Endogâmicos F344 , Fatores de Tempo
12.
J Natl Cancer Inst ; 77(1): 213-7, 1986 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3459914

RESUMO

The effects of the chronic administration of methyl-deficient, amino acid-defined diets on liver tumor formation were examined in male weanling C3H/HeN mice previously treated with a single ip injection of 0 or 150 mg diethylnitrosamine/kg body weight [(DENA) CAS: 55-18-5]. Five diets were used: diet 1, adequate; diet 2, devoid of both methionine and choline; diet 3, devoid of methionine only; diet 4, devoid of choline only; and diet 5, devoid of methionine, choline, folic acid, and vitamin B12. Equimolar homocystine replaced methionine in all methionine-devoid diets. All diets were administered for 1 year. No hepatocellular carcinomas and only 3 liver adenomas were seen among the 129 animals at risk in the 5 groups that had received no DENA. Among the DENA-treated groups fed diets 1-4, the incidence of hepatocellular carcinomas in the mice at risk averaged 40%, with no significant differences noted among groups. A relatively low incidence of liver carcinomas (10%) was seen among DENA-treated mice subsequently fed diet 5; it could be ascribed to the enhanced mortality seen in these animals due to the dietary deficiencies. Lung tumors were seen in 44% of the DENA-treated mice surviving more than 35 experimental weeks and in only 2.5% of the corresponding DENA-untreated animals. Feeding diet 2, deficient in methionine and choline, to male C3H mice for 5-20 weeks decreased the hepatic ratio of S-adenosylmethionine (CAS: 29908-3-0) to S-adenosylhomocysteine (979-92-0) relative to that observed in mice fed the adequate diet 1. The 5-methyldeoxycytidine [(5-MC) CAS: 838-07-3] contents of liver DNA in animals fed diet 2 for 5, 10, and 20 weeks, however, were not significantly different from the corresponding levels in diet 1-fed mice. The results indicate that a methionine- and choline-deficient dietary regimen that lowers the 5-MC levels in DNA and enhances liver tumor formation in male F344 rats does not do so in male C3H mice.


Assuntos
Colina/administração & dosagem , DNA/metabolismo , Neoplasias Hepáticas/etiologia , Fígado/metabolismo , Metionina/administração & dosagem , Animais , Peso Corporal , Colina/metabolismo , Desoxicitidina/análogos & derivados , Desoxicitidina/metabolismo , Dieta , Dietilnitrosamina , Masculino , Metionina/metabolismo , Metilação , Camundongos , Camundongos Endogâmicos C3H , Tamanho do Órgão , S-Adenosil-Homocisteína/metabolismo , S-Adenosilmetionina/metabolismo , Fatores de Tempo
13.
Cancer Res ; 43(10): 4575-81, 1983 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6883316

RESUMO

The effects of calcium and magnesium acetates on the formation of injection site and testicular tumors in male Wistar rats over 2 years following s.c. injections of cadmium chloride (CdCl2) were determined. The rats (25/group) received a single s.c. dose of CdCl2 (0.02 or 0.04 mmol/kg; 0.9% NaCl solutions). Calcium and magnesium acetates were administered as 3% dietary supplements for 2 weeks prior to and 2 weeks after the CdCl2 injection, or as three daily s.c. injections (0.16 mmol calcium acetate per kg, 4 mmol magnesium acetate per kg; 0.9% NaCl solutions) at the same site as CdCl2 on the day before, the day of, and the day after CdCl2 dosing. Control groups were given 0.9% NaCl solution instead of CdCl2 plus s.c. or dietary calcium and magnesium acetates. In rats given injections of CdCl2 alone, the final tumor yields were 33 and 34% of rats at risk at the injection site (mostly fibrosarcomas) and 86 and 85% of rats at risk in the testes (mostly interstitial cell tumors), respectively, for the low- and high-CdCl2 doses. In control rats, the corresponding tumor yields were 0% at the site of 0.9% NaCl solution injection and 30% in the testes. Dietary calcium and magnesium acetates or s.c. calcium acetate did not affect significantly the tumor yields and latent periods. Simultaneous injections of magnesium acetate at the same site completely prevented the development of injection site tumors for both CdCl2 doses but had no effect on the final yields of testicular tumors. CdCl2 injection also caused significant elevation of incidence of the pancreatic islet cell tumors (8.5 versus 2.2%) regardless of any other experimental treatment. These results provide further evidence that the divalent carcinogenic metals may exert their activity through an antagonism with the physiologically essential divalent metals.


Assuntos
Acetatos/farmacologia , Cádmio/farmacologia , Carcinógenos , Magnésio/farmacologia , Neoplasias/induzido quimicamente , Ácido Acético , Animais , Peso Corporal/efeitos dos fármacos , Cloreto de Cádmio , Masculino , Neoplasias Pancreáticas/induzido quimicamente , Ratos , Ratos Endogâmicos , Neoplasias Cutâneas/induzido quimicamente , Neoplasias Testiculares/induzido quimicamente
14.
Genetics ; 135(2): 507-26, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8244011

RESUMO

The products of the forked gene are involved in the formation and/or maintenance of a temporary fibrillar structure within the developing bristle rudiment of Drosophila melanogaster. Mutations in the forked locus alter this structure and result in aberrant development of macrochaetae, microchaetae and trichomes. The locus has been characterized at the molecular level by walking, mutant characterization and transcript analysis. Expression of the six forked transcripts is temporally restricted to mid-late pupal development. At this time, RNAs of 6.4, 5.6, 5.4, 2.5, 1.9 and 1.1 kilobases (kb) are detected by Northern analysis. The coding region of these RNAs has been found to be within a 21-kb stretch of genomic DNA. The amino terminus of the proteins encoded by the 5.4- and 5.6-kb forked transcripts contain tandem copies of ankyrin-like repeats that may play an important role in the function of forked-encoded products. The profile of forked RNA expression is altered in seven spontaneous mutations characterized during this study. Three forked mutations induced by the insertion of the gypsy retrotransposon contain a copy of this element inserted into an intron of the gene. In these mutants, the 5.6-, 5.4- and 2.5-kb forked mRNAs are truncated via recognition of the polyadenylation site in the 5' long terminal repeat of the gypsy retrotransposon. These results help explain the role of the forked gene in fly development and further our understanding of the role of transposable elements in mutagenesis.


Assuntos
Elementos de DNA Transponíveis , Proteínas de Drosophila , Drosophila melanogaster/genética , Expressão Gênica , Hormônios de Inseto/genética , Mutagênese Insercional , Sequência de Aminoácidos , Animais , Anquirinas/genética , Sequência de Bases , Sequência Consenso , DNA/química , DNA/genética , Drosophila melanogaster/ultraestrutura , Proteínas dos Microfilamentos , Microscopia Eletrônica de Varredura , Dados de Sequência Molecular , Fenótipo , Sequências Repetitivas de Ácido Nucleico , Mapeamento por Restrição , Homologia de Sequência de Aminoácidos , Transcrição Gênica
15.
Genetics ; 132(3): 691-7, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1334893

RESUMO

Mutations induced by the gypsy retrotransposon in the forked (f) and cut (ct) loci render their expression under the control of the suppressor of Hairy-wing [su(Hw)] gene. This action is usually recessive, but su(Hw) acts as a dominant on the alleles fk, ctk and ctMRpN30. Molecular analysis of the gypsy element present in fk indicates that this allele is caused by the insertion of a modified gypsy in which the region normally containing twelve copies of the octamer-like repeat that interacts with the su(Hw) product is altered. Analysis of the gypsy element responsible for the ctk and ctMRpN30 mutations also reveals a correlation between the dominant action of su(Hw) and disruption of the octamer region. We propose that these disruptions alter the affinity and interaction of su(Hw) protein with gypsy DNA, thereby sensitizing the mutant phenotype to fluctuations in su(Hw) product.


Assuntos
Elementos de DNA Transponíveis , Drosophila melanogaster/genética , Genes Dominantes , Mutagênese Insercional , Alelos , Animais , Sequência de Bases , Elementos de DNA Transponíveis/genética , Drosophila melanogaster/anatomia & histologia , Genes Supressores , Dados de Sequência Molecular , Fenótipo
16.
J Invest Dermatol ; 82(3): 214-8, 1984 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6699424

RESUMO

Benoxaprofen (BXP) is a nonsteroidal anti-inflammatory drug which causes cutaneous phototoxicity. Because the in vivo phototoxicity may involve photosensitized damage to mast cell membranes, the mechanism for photosensitized damage was studied in a single model system, the red blood cell. Oxygen-dependent and oxygen-independent mechanisms for membrane disruption were detected. Oxygen-dependent lysis was not quenched by superoxide dismutase and was quenched only at high sodium azide concentrations. A two-step mechanism is proposed involving initial photodecarboxylation of BXP to form a lipophilic photoproduct which subsequently photosensitizes membrane damage. Human serum albumin at 0.03% totally inhibited BXP-photosensitized lysis.


Assuntos
Anti-Inflamatórios/farmacologia , Fármacos Dermatológicos/farmacologia , Membrana Eritrocítica/efeitos dos fármacos , Transtornos de Fotossensibilidade/induzido quimicamente , Propionatos/farmacologia , Azidas/farmacologia , Cromatografia Líquida de Alta Pressão , Hemólise , Humanos , Técnicas In Vitro , Transtornos de Fotossensibilidade/patologia , Albumina Sérica/farmacologia , Azida Sódica , Espectrometria de Fluorescência , Superóxido Dismutase/farmacologia , Raios Ultravioleta
17.
Hypertension ; 23(6 Pt 2): 857-60, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8206618

RESUMO

A chymase (also referred to as angiotensin I-convertase) specific for the conversion of angiotensin (Ang) I to Ang II has been identified in human heart. This serine protease is also present in dog and marmoset vasculature. We examined the vasoconstrictor effects of Ang II putatively generated from an angiotensin-converting enzyme (ACE)-resistant convertase synthetic substrate (SUB) in vivo and in vitro. In marmosets, SUB (7 to 700 micrograms/kg i.v.) or Ang I (0.1 to 30 micrograms/kg) caused similar dose-dependent increases in mean arterial pressure (10 to 100 mm Hg) and decreases in heart rate. Pressor effects of SUB were slightly attenuated at low (but not high) doses by captopril (CAP, 1 mg/kg i.v.) and blocked by losartan (5 mg/kg i.v.); in contrast Ang I pressor effects were substantially blocked by both. In isolated canine superior mesenteric artery, Ang I-induced contraction was eliminated by losartan and reduced but not eliminated by 10 mumol/L CAP. When combined with the serine protease inhibitor chymostatin, CAP eliminated Ang I-induced contraction, but chymostatin alone had no effect. SUB-induced contraction was not blocked by CAP but was equally blocked by chymostatin (25 mumol/L) alone or by the combination of CAP (10 mumol/L) and chymostatin (25 mumol/L); losartan (10 mumol/L) eliminated SUB-induced responses. Previous studies have suggested that Ang I-convertase is important for production of Ang II in the heart. Our results are consistent with a potential role for Ang I-convertase in the production of Ang II in the vasculature, resulting in Ang II-mediated vasoconstriction.


Assuntos
Angiotensina I/análogos & derivados , Artérias Mesentéricas/efeitos dos fármacos , Serina Endopeptidases/farmacologia , Vasoconstritores/farmacologia , Angiotensina I/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Callithrix , Captopril/farmacologia , Quimases , Cães , Relação Dose-Resposta a Droga , Feminino , Técnicas In Vitro , Masculino , Cloreto de Potássio/farmacologia
18.
Biol Psychiatry ; 28(5): 425-34, 1990 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-2207220

RESUMO

Dynamic computed tomography (CT) scanning of the brain was performed in 26 patients with primary degenerative dementia (PDD) and in 15 age-matched controls without evidence of a dementing illness. Changes in CT density values over time were obtained for 16 regions of interest (ROIs) that were carefully chosen to avoid overlap with adjacent cerebrospinal fluid (CSF), sulsi, or bone. CT density washout curves were compared between patients and controls to detect regions where blood brain barrier (BBB) permeability might be increased. Although the patients' washout curves declined more gradually than control curves in 11 of the 14 ROIs with a functioning BBB, in no case did the difference reach statistical significance. Intrarater correlation coefficients indicated good overall reliability in the selection of ROIs.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Barreira Hematoencefálica/fisiologia , Encéfalo/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Idoso , Idoso de 80 Anos ou mais , Permeabilidade Capilar/fisiologia , Córtex Cerebral/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
19.
Biol Psychiatry ; 31(1): 4-18, 1992 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-1543797

RESUMO

Neuropsychological functioning was examined in a group of 18 nondepressed patients with obsessive-compulsive disorder (OCD) and 18 age-, education-, and gender-matched normal controls. A recent nonverbal memory deficit was identified in the patients with OCD. From performance on timed and untimed measures of the same constructs, it appears that OCD patients score more poorly than controls when speed is a factor. Although performance on a timed tactual-spatial motor test was also impaired, it is unclear whether this deficit is attributable to the nonverbal memory and/or speed deficits. Deficits in verbal abilities, including recent verbal memory, were not identified. Results were equivocal for executive function and visual-spatial abilities. The previously established association of recent nonverbal memory abilities with functioning of the right mesial temporal area is discussed in the context of current hypotheses about the neuroanatomic substrate of OCD.


Assuntos
Transtorno Obsessivo-Compulsivo/psicologia , Desempenho Psicomotor/fisiologia , Adulto , Clomipramina/uso terapêutico , Cognição/fisiologia , Educação , Feminino , Humanos , Masculino , Memória de Curto Prazo/fisiologia , Transtorno Obsessivo-Compulsivo/tratamento farmacológico , Escalas de Graduação Psiquiátrica , Psicometria , Percepção Espacial/fisiologia , Comportamento Verbal/fisiologia , Escalas de Wechsler
20.
Biol Psychiatry ; 42(11): 969-75, 1997 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-9386847

RESUMO

BACKGROUND: Inclusion of obsessive-compulsive disorder (OCD) as an anxiety disorder in DSM-i.v. assumes that anxiety is the primary symptom of OCD; however, persuasive empirical evidence in support of this view has not been presented yet. In the present study we hypothesized that provoked anxiety symptoms respond better to intravenous diazepam than would provoked obsessions. We, therefore, reasoned that anxiety symptoms are secondary symptoms of OCD. METHODS: To test the hypothesis we designed a double-blind, randomized, placebo-controlled crossover study. Patients underwent four experimental conditions in which the sequence of symptom provocation and i.v. injection of (placebo or diazepam) were alternated. Baseline and i.v. injection-induced symptom changes were assessed using visual analogs. RESULTS: Obsessions and anxiety correlated strongly for all four experimental conditions in which the sequence of the symptom provocation and diazepam i.v. injections was alternated. i.v. diazepam injection before and after symptom provocation failed to preferentially modulate anxiety symptoms over obsessions. Unexpectedly, in the group in which i.v. diazepam injection preceded the symptom provocation, reduction of mean obsessions was even more pronounced. CONCLUSIONS: Strong correlations between anxiety and obsessions at baseline, during symptom provocation, and after i.v. diazepam infusion suggest that anxiety and obsessions are tightly coupled phenomena in OCD.


Assuntos
Ansiedade/tratamento farmacológico , Ansiedade/psicologia , Comportamento Obsessivo/tratamento farmacológico , Comportamento Obsessivo/psicologia , Transtorno Obsessivo-Compulsivo/tratamento farmacológico , Transtorno Obsessivo-Compulsivo/psicologia , Adulto , Ansiolíticos/administração & dosagem , Ansiolíticos/uso terapêutico , Ansiedade/fisiopatologia , Pressão Sanguínea/fisiologia , Diazepam/administração & dosagem , Diazepam/uso terapêutico , Método Duplo-Cego , Feminino , Frequência Cardíaca/fisiologia , Humanos , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Comportamento Obsessivo/fisiopatologia , Transtorno Obsessivo-Compulsivo/fisiopatologia , Escalas de Graduação Psiquiátrica , Mecânica Respiratória/fisiologia
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