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1.
Biol Lett ; 14(7)2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-30021863

RESUMO

Animals use multiple signals to attract mates, including elaborate song, brightly coloured ornaments and physical displays. Female birds often prefer both elaborate male song and intense carotenoid-based plumage coloration. This could lead less visually ornamented males to increase song production to maximize their attractiveness to females. We tested this possibility in the highly social and non-territorial house finch (Haemorhous mexicanus), in which females discriminate among males based on both song and on the intensity of red carotenoid-based plumage coloration. We manipulated male plumage coloration through carotenoid supplementation during moult, so that males were either red or yellow. Males were then housed under three social environments: (i) all red birds, (ii) all yellow birds or (iii) a mixture of red/yellow birds. We recorded song after presentation of a female. Red males produced more song than yellow males. But when yellow males were housed with red conspecifics, they produced more song relative to yellow males housed with equally unattractive yellow males. This study provides novel evidence that a male's plumage coloration and the plumage colour of his social competitors influence investment in song.


Assuntos
Plumas/fisiologia , Passeriformes/fisiologia , Pigmentação/fisiologia , Vocalização Animal/fisiologia , Animais , Carotenoides , Comportamento Competitivo/fisiologia , Feminino , Masculino , Passeriformes/anatomia & histologia , Comportamento Sexual Animal/fisiologia
2.
R Soc Open Sci ; 4(10): 170875, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29134087

RESUMO

Glucocorticoids, including corticosterone (CORT), have been suggested to provide a physiological link between ecological conditions and fitness. Specifically, CORT, which is elevated in response to harsh conditions, is predicted to be correlated with reduced fitness. Yet, empirical studies show that CORT can be non-significantly, positively and negatively linked with fitness. Divergent environmental conditions between years or study systems may influence whether CORT is linked to fitness. To test this, we monitored free-living blue tits (Cyanistes caeruleus) during breeding over 3 years. We quantified foraging conditions during brood rearing, and examined whether they were correlated with parental baseline CORT and reproductive success. We then tested whether CORT predicted fitness. Elevated parental CORT was associated with lower temperatures, greater rainfall and lower territory-scale oak density. Whereas asynchrony with the caterpillar food peak was correlated with reduced nestling mass and fledging success, but not parental CORT. Only low temperatures were associated with both reduced nestling mass and elevated parental CORT. Despite this, parents with elevated CORT had lighter offspring in all years. Contrarily, in 2009 parental CORT was positively correlated with the number fledged. The absence of a direct link between the foraging conditions that reduce nestling quality and elevate parental CORT suggests that parental CORT may provide a holistic measure of conditions where parents are working harder to meet the demands of developing young. As the positive correlation between parental CORT and fledging success differed between years, this suggests that contrasting conditions between years can influence correlations between parental CORT and fitness. Ultimately, as CORT concentrations are intrinsically variable and linked to the prevalent conditions, studies that incorporate environmental harshness will improve our understanding of evolutionary endocrinology.

3.
Eur J Pharmacol ; 106(1): 195-7, 1984 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-6529967

RESUMO

Buspirone, a non-benzodiazepine anxiolytic agent, produced dose-dependent increases in the activity of norepinephrine-containing locus coeruleus neurons recorded from mouse brain slices in vitro. The response was not changed in a low calcium/high magnesium incubation medium, indicating that the observed effects were the result of a direct action of buspirone on locus coeruleus neurons. These data suggest that noradrenergic neurons may not be as important in mediating anxiety states as previously suggested.


Assuntos
Locus Cerúleo/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Norepinefrina/fisiologia , Pirimidinas/farmacologia , Potenciais de Ação/efeitos dos fármacos , Animais , Buspirona , Técnicas In Vitro , Locus Cerúleo/fisiologia , Masculino , Camundongos , Neurônios/fisiologia
4.
Eur J Pharmacol ; 96(1-2): 151-4, 1983 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-6581976

RESUMO

The characteristic behavioral effects of mescaline in cats were nearly completely blocked by pretreatment with low doses of either a specific serotonin antagonist (methysergide) or a dopamine specific antagonist (haloperidol). These blocking effects were not due to non-specific actions, since methysergide did not block the behavioral effects of apomorphine, and haloperidol did not block the behavioral effects of 5-methoxy-N,N-dimethyltryptamine. Thus, it appears that the behavioral effects of mescaline are dependent upon the simultaneous action of the drug at both serotonin and dopamine receptors.


Assuntos
Comportamento Animal/efeitos dos fármacos , Haloperidol/farmacologia , Mescalina/antagonistas & inibidores , Metisergida/farmacologia , 5-Metoxitriptamina/farmacologia , Animais , Apomorfina/farmacologia , Gatos , Interações Medicamentosas , Feminino , Masculino , Mescalina/farmacologia , Receptores Dopaminérgicos/efeitos dos fármacos , Receptores de Serotonina/efeitos dos fármacos
5.
J Pharm Pharmacol ; 37(12): 930-1, 1985 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2868111

RESUMO

Pretreatment with ascorbic acid (500 mg kg-1 i.p.) antagonized the behavioural effects of lysergic acid diethylamide (LSD) and apomorphine, but not 5-methoxy-N,N-dimethyltryptamine, in cats. The data support the hypothesis that these behavioural effects in cats are due to drug action at both 5-HT and dopamine receptors, and that the action of LSD at dopamine receptors is modulated by ascorbic acid.


Assuntos
Ácido Ascórbico/farmacologia , Comportamento Animal/efeitos dos fármacos , Dietilamida do Ácido Lisérgico/antagonistas & inibidores , Animais , Apomorfina/farmacologia , Gatos , Metoxidimetiltriptaminas/farmacologia
6.
Dent Mater ; 5(5): 306-9, 1989 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2517836

RESUMO

The purpose of this study was to test the effectiveness and shelf life of a commercially available glutaraldehyde/methacrylate dentin adhesive (Gluma). The measurement of marginal contraction gaps in 320 cavities restored over a period of 415 days was the basis for these determinations. The results showed that Gluma dentin adhesive was more effective with one of the two composite restorative materials used for the study, and that the shelf life of Gluma exceeded 415 days.


Assuntos
Aldeídos , Glutaral , Ácidos Polimetacrílicos , Cimentos Dentários , Humanos , Fatores de Tempo
7.
Oper Dent ; 17(1): 7-12, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1437685

RESUMO

The purpose of this research effort was to investigate the microleakage of cervical restorations lined with a light-cured glass-ionomer liner. Wedge-shaped cervical cavities were cut on extracted teeth with the gingival cavosurface margin involving dentin. The cavities were randomly assigned to each of each of three groups: (1) restored with a microfilled composite resin, (2) restored with a light-cured glass-ionomer liner and microfilled resin as in the "sandwich" technique, and (3) restored entirely with the light-cured glass-ionomer liner. Half of the specimens in each group were thermocycled. Microleakage of these restorations was assessed by dye penetration. The results showed that differences were more pronounced at the gingival margin. Composite restorations inserted over the glass-ionomer liner demonstrated significantly less leakage than when the liner was not used.


Assuntos
Resinas Compostas , Forramento da Cavidade Dentária , Infiltração Dentária/prevenção & controle , Cimentos de Ionômeros de Vidro , Colagem Dentária , Restauração Dentária Permanente/métodos , Humanos , Teste de Materiais , Raiz Dentária
8.
Oper Dent ; 15(5): 167-72, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2098725

RESUMO

Differences in microleakage at occlusal and cervical margins have been attributed to variations in the microstructure of enamel. The lack of homogeneity in dentin may have similar influences on the effectiveness of composite bonding. This study examined marginal contraction gaps occurring at the occlusal, cervical, mesial, and distal margins of dentin cavities restored with a composite restorative material, with and without the use of dentin bonding agents. Results showed that marginal contraction gaps at the dentin-restoration interface among the four sites in both treated and untreated cavities are not statistically different in size. Adhesion of composite restorative materials to dentin is not affected by the location of the margins.


Assuntos
Colagem Dentária , Preparo da Cavidade Dentária , Infiltração Dentária , Resinas Compostas , Dentina , Humanos , Propriedades de Superfície
9.
Oper Dent ; 16(6): 218-22, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1816543

RESUMO

The purpose of this research effort was to investigate the effect of age changes in dentin on the effectiveness of two dentin adhesives in minimizing microleakage at the tooth-restoration interface. Cavities were prepared in permanent teeth extracted from patients below 20 years or over 55 years of age. Wedge-shaped cervical preparations were made with the gingival cavosurface margin on dentin. Treatment groups were randomly restored with one of two composite restorative materials, together with the appropriate dentin adhesives. The control group specimens were restored with the respective composite restorative materials without the adhesives. All specimens were thermocycled, then placed in 0.5% basic fuchsin dye solution for 24 hours and subsequently sectioned longitudinally. Microleakage at the tooth-restoration interface was assessed by dye penetration. The results showed that the use of adhesives significantly reduced microleakage along the tooth-restoration interface. The adhesive formulated with glycidyl methacrylate was significantly more effective in reducing microleakage in dentin of the over-55 age group.


Assuntos
Adesivos , Envelhecimento , Colagem Dentária , Adesivos Dentinários , Dentina , Cimentos de Resina , Adolescente , Adulto , Fatores Etários , Idoso , Distribuição de Qui-Quadrado , Criança , Corantes , Resinas Compostas , Infiltração Dentária/prevenção & controle , Restauração Dentária Permanente , Temperatura Alta , Humanos , Metacrilatos , Pessoa de Meia-Idade
10.
Am J Dent ; 5(5): 240-4, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1299247

RESUMO

This paper reports the effect of dentin bonding agents on marginal leakage in cervical cavities without the classical cavity preparation design. Wedge-shaped cervical cavities were cut on extracted teeth with the gingival cavosurface margin of each cavity involving dentin. The specimens were randomly assigned to three groups of 40 each: Group 1 (control), restored with Fuji glass ionomer; Group 2, restored with Scotchbond 2 adhesive and Silux Plus resin and Group 3, restored with Tenure adhesive and Perfection resin. Half of the specimens in each group were thermocycled. All specimens were then stored in basic fuchsin dye after which microleakage of the restorations was assessed by dye penetration. A grading scale of 0 to 3 was used as the scoring criteria. The results showed that differences were more pronounced at the gingival margin. The control group specimens exhibited the least microleakage. There was no significant difference between thermocycled and non-thermocycled specimens for each category of materials used. There was, however, a significant difference between the experimental groups and the control groups. The dentin adhesives tested did not completely eliminate microleakage at the gingival margin of cervical cavities.


Assuntos
Resinas Compostas , Infiltração Dentária , Restauração Dentária Permanente/métodos , Adesivos Dentinários , Cimentos de Resina , Cárie Radicular/terapia , Análise de Variância , Preparo da Cavidade Dentária , Esmalte Dentário , Dentina , Humanos , Metacrilatos
11.
Ann Acad Med Singap ; 18(5): 569-72, 1989 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2694914

RESUMO

Composite resin restorative materials have been used in dental practice for over 25 years. The original composite resins were subjected to discolouration and marginal breakdown. These problems have largely been overcome with the exception of marginal gaps at the dentine-restoration interface. The introduction of dentine adhesives has reduced but not eliminate this problem. This study shows how the marginal gaps at the dentine-restoration interface were significantly reduced firstly by the introduction of an intermediate resin and then further by using a dentine adhesive.


Assuntos
Adesivos , Resinas Compostas , Colagem Dentária , Restauração Dentária Permanente , Adesivos Dentinários , Cimentos de Resina , Fenômenos Químicos , Físico-Química , Infiltração Dentária/diagnóstico , Dentina , Humanos , Resinas Sintéticas , Propriedades de Superfície
12.
Singapore Dent J ; 21(1): 23-5, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10597179

RESUMO

The traditional laboratory testing (mechanical testing and microleakage testing) of the adhesion of restorative materials to dentine is of a destructive nature. A non-destructive laboratory method of testing the material-dentine bond using ultrasonics has been devised and compared to mechanical shear testing. Similar results were obtained with both testing methods. It this study thermocycling was shown to have no statistically significant effect on the glass-ionomer dentine bond.


Assuntos
Colagem Dentária , Adesivos Dentinários , Cimentos de Ionômeros de Vidro , Teste de Materiais/métodos , Resinas Compostas , Dentina , Temperatura Alta , Humanos , Resistência à Tração , Ultrassom
13.
Singapore Dent J ; 14(1): 3-5, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2518647

RESUMO

This study was undertaken to test the effectiveness of using two dentine adhesives in combination. One of the dentine adhesives used adhered to the calcium in the dentine while the other dentine adhesive adhered to the organic portion of the dentine. It was hoped by using them in combination that their actions would complement each other producing composite restorations with gap free margins. Results showed an increase in the number of gap free restorations but the marginal contraction gaps were not entirely eliminated.


Assuntos
Adesivos , Colagem Dentária , Cimentos Dentários , Infiltração Dentária/prevenção & controle , Adesivos Dentinários , Cálcio , Colágeno , Dentina/química , Combinação de Medicamentos , Estudos de Avaliação como Assunto , Glutaral , Humanos , Propriedades de Superfície
14.
Singapore Dent J ; 13(1): 1-3, 1988 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3155334

RESUMO

Previous studies have shown that dentine adhesives reduce or eliminate contraction gaps in composite restorations. This study examined the relationship between cavity site and contraction gaps when two dentine adhesives were used in combination with two composites. One hundred and fifty-two cavities, each measuring 2.0 mm diameter and 1.5 mm depth, were prepared on side surfaces of extracted teeth, with each surface classified into three levels: upper, middle and lower. The dentine adhesives and composites were randomly assigned to the cavities. Four pre-determined, diametrical measurements of contraction gaps were made for each restored cavity using a Nikon Measurescope. Measurements yielded overall mean contraction gaps of 0.229, 0.262, and 0.260 for upper, middle and lower levels on the crown; the differences between means were not statistically significant. Type of dentine adhesives and composites influenced the size of contraction gaps rather than cavity site.


Assuntos
Resinas Compostas , Colagem Dentária , Cimentos Dentários , Infiltração Dentária/etiologia , Glutaral , Ácidos Polimetacrílicos , Cimentos de Resina , Preparo da Cavidade Dentária , Dentina , Humanos
15.
AORN J ; 71(3): 525-30, 533-6, 538, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10736638

RESUMO

Interstitial cystitis (IC) is a chronic inflammation of all the layers of the bladder wall. As it is difficult to diagnose and it affects mostly women, many physicians misdiagnose it as a psychological problem. Almost half a million individuals in the United States suffer from this cureless disorder. This article will review the anatomy, physiology, etiology, diagnosis, treatments, and current research foci of IC, along with the effects of the disease on lifestyle and personal issues from the patient's perspective.


Assuntos
Cistite Intersticial/terapia , Adulto , Atitude Frente a Saúde , Doenças Autoimunes/etiologia , Cistite Intersticial/diagnóstico , Cistite Intersticial/etiologia , Cistite Intersticial/psicologia , Feminino , Humanos , Estilo de Vida
16.
AORN J ; 61(4): 671-7, 679, 682-5, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7793900

RESUMO

Percutaneous transluminal balloon angioplasty (PTBA) is a minimally invasive and effective adjunct treatment for patients with atherosclerotic peripheral vascular disease. This surgical technique involves placing an intraarterial balloon within an obstructing arterial lesion and forcibly dilating the balloon under fluoroscopy. The PTBA technique has become an accepted interventional therapy for iliac artery stenoses. In selected patients with stenotic lesions of the iliac artery, percutaneous transluminal angioplasty (PTA) with the use of an intravascular stent may be an alternative to traditional aortofemoral bypass surgery. The PTA procedure involves only a needle entry site in one or both groins as opposed to an incision exposing the entire abdomen. The hospital stay for the average patient undergoing PTA of the iliac artery is three days as opposed to seven days for the patient undergoing aortofemoral bypass, and the patient may return to normal activity in a much shorter period of time after a PTA procedure.


Assuntos
Angioplastia com Balão/enfermagem , Arteriopatias Oclusivas/enfermagem , Arteriopatias Oclusivas/terapia , Artéria Ilíaca , Stents , Angioplastia com Balão/métodos , Terapia Combinada , Humanos , Artéria Ilíaca/cirurgia , Masculino , Pessoa de Meia-Idade , Enfermagem de Centro Cirúrgico , Stents/classificação
17.
AORN J ; 63(2): 450-1, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8907749

RESUMO

Historically, the discussion of which products to use in a hospital has centered around disposable versus reusable products; however, new technology has produced a line of products that are not only disposable but degradable. Perioperative staff members at Redmond Regional Medical Center, Rome, Ga, participated in the testing, evaluation, and use of these prototype products during their development.


Assuntos
Equipamentos Descartáveis/normas , Teste de Materiais , Salas Cirúrgicas , Equipamentos Descartáveis/economia , Humanos , Recursos Humanos de Enfermagem Hospitalar , Serviço Hospitalar de Compras , Estados Unidos , Gerenciamento de Resíduos
18.
Indian J Dent Res ; 2(1): 123-6, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2096955

RESUMO

There is a tendency to interchange dentine adhesives and composite resins when using composite resins for restorations. This study used marginal contraction gaps to test the effect of changing composite resins with a dentine adhesive. Cylindrical butt-joint cavities were prepared entirely in dentine using extracted human teeth. Two groups of control cavities (30 cavities per group) were restored with Prisma-Bond/Prisma-Fil and Heliobond/Heliomolar respectively. Two groups of test cavities (30 cavities per group) were restored using the dentine adhesive. Prisma Universal Bond with Prisma-Fil on one group and Prisma Universal Bond and Heliomolar in the other. Following thermocycling the marginal contraction gaps were measured and assessed. The results showed a significant reduction in marginal contraction gaps when using either composite resin with Prisma Universal Bond. This indicates a compatibility of both resins with the adhesive in this instance.


Assuntos
Resinas Compostas , Colagem Dentária , Infiltração Dentária/prevenção & controle , Dentina , Cimentos de Resina , Acrilatos , Resinas Acrílicas , Adesivos , Humanos , Poliuretanos , Resinas Sintéticas
20.
Br J Cancer ; 92(8): 1553-60, 2005 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-15785753

RESUMO

Genetic alterations occurring on human chromosome arm 1p are common in many types of cancer including lung, breast, neuroblastoma, pheochromocytoma, and colorectal. The identification of tumour suppressors and oncogenes on this arm has been limited by the low resolution of current technologies for fine mapping. In order to identify genetic alterations on 1p in small-cell lung carcinoma, we developed a new resource for fine mapping segmental DNA copy number alterations. We have constructed an array of 642 ordered and fingerprint-verified bacterial artificial chromosome clones spanning the 120 megabase (Mb) 1p arm from 1p11.2 to p36.33. The 1p arm of 15 small-cell lung cancer cell lines was analysed at sub-Mb resolution using this arm-specific array. Among the genetic alterations identified, two regions of recurrent amplification emerged. They were detected in at least 45% of the samples: a 580 kb region at 1p34.2-p34.3 and a 270 kb region at 1p11.2. We further defined the potential importance of these genomic amplifications by analysing the RNA expression of the genes in these regions with Affymetrix oligonucleotide arrays and semiquantitative reverse transcriptase-polymerase chain reaction. Our data revealed overexpression of the genes HEYL, HPCAL4, BMP8, IPT, and RLF, coinciding with genomic amplification.


Assuntos
Carcinoma de Células Pequenas/genética , Cromossomos Humanos Par 1/genética , Perfilação da Expressão Gênica , Neoplasias Pulmonares/genética , Animais , Linhagem Celular Tumoral , Mapeamento Cromossômico , Cromossomos Artificiais Bacterianos , Amplificação de Genes , Humanos , Hibridização In Situ , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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