RESUMO
Conventionally, nasotracheal intubation has consisted of blind nasal passage and external manipulation of the tube through the glottis ('conventional technique'), a technique associated with a high incidence of nasal trauma. We evaluated a novel technique for routine asleep (i.e. post-induction) nasotracheal intubation using a bougie ('bougie technique'), which uses a nasopharyngeal airway to guide a paediatric bougie nasotracheally for use as a Seldinger tracheal intubation guide. Two hundred and fifty-seven older children (> 8 years) and adults were randomly assigned to videolaryngoscopy-assisted nasotracheal intubation using either the conventional or the bougie technique. The hypothesis was that the bougie technique would result in less nasopharyngeal trauma. The bougie technique was associated with significantly less nasopharyngeal bleeding than the conventional technique at both 60-90 s (55% vs. 68%; p = 0.033) and 5 min (51% vs. 70%; p = 0.002). The severity of bleeding was also significantly less with the bougie technique, with an OR for active bleeding of 0.42 (95%CI 0.20-0.87; p = 0.020) at 60-90 s and 0.15 (95%CI 0.06-0.37; p < 0.0001) at 5 min. Magill forceps were needed significantly less often with the bougie technique (9% vs. 28%, p = 0.0001) and there was no difference in first attempt and overall success rates between the two techniques (p = 0.133 and p = 0.750, respectively). Not only is nasal intubation over a bougie as successful as the conventional technique, it also significantly decreases both the incidence and severity of nasopharyngeal trauma, as well as the need for the use of Magill forceps.
Assuntos
Intubação Intratraqueal/instrumentação , Intubação Intratraqueal/métodos , Laringoscopia/instrumentação , Laringoscopia/métodos , Adolescente , Adulto , Idoso , Criança , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Gravação de Videoteipe , Adulto JovemRESUMO
Diagnostic journey for people with FKRP mutations participating in a dystroglycanopathy natural history study (nâ¯=â¯68; NCT00313677) was analyzed. Earliest symptoms and age at muscular dystrophy diagnosis were abstracted from subject-reported medical history and record review. Initial signs/symptoms were classified as chronic motor dysfunction (e.g., delayed motor milestones, weakness, falling; nâ¯=â¯40, 59%), elevated transaminases (nâ¯=â¯7, 10%), or acute/intermittent symptoms (myoglobinuria, myalgia, febrile illness-associated acute weakness; nâ¯=â¯21, 31%). Median time from sign/symptom onset to diagnosis was 6.5 years and differed by symptom group: 7.5 years for motor group, 9 years for acute/intermittent group, and 4 years for elevated transaminases group. The sign/symptom category that most commonly resulted in a diagnosis was chronic motor dysfunction (nâ¯=â¯45). Of those without clear weakness as first symptom (nâ¯=â¯55), 36.4% were not diagnosed with MD until weakness became apparent. Median time to diagnosis was shortest for those with febrile illness-associated acute weakness (0.25 years). Median time from first sign/symptom to MD diagnosis has decreased incrementally from 18.8 years for those with onset in the 1970s to < 10 years for symptom onset occurring after 2000. Awareness of disease presentation variability will aid in earlier diagnosis, which is increasingly important with treatments in development.
Assuntos
Distrofias Musculares/diagnóstico , Distrofias Musculares/fisiopatologia , Adolescente , Adulto , Idoso , Criança , Diagnóstico Tardio , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Debilidade Muscular/etiologia , Debilidade Muscular/fisiopatologia , Distrofias Musculares/complicações , Distrofias Musculares/genética , Mioglobinúria/etiologia , Pentosiltransferases/genética , Adulto JovemRESUMO
Alveolar ridge preservation (ARP) therapy is indicated to attenuate the physiologic resorptive events that occur as a consequence of tooth extraction with the purpose of facilitating tooth replacement therapy. This randomized controlled trial was primarily aimed at testing the efficacy of ARP as compared with unassisted socket healing. A secondary objective was to evaluate the effect that local phenotypic factors play in the volumetric reduction of the alveolar bone. A total of 53 subjects completed the study. Subjects were randomized into either the control group, which involved only tooth extraction (EXT n = 27), or the experimental group, which received ARP using a combination of socket grafting with a particulate bone allograft and socket sealing with a nonabsorbable membrane (dPTFE) following tooth extraction (ARP n = 26). A set of clinical, linear, volumetric, implant-related, and patient-reported outcomes were assessed during a 14-wk healing period. All linear bone assessments (horizontal, midbuccal, and midlingual reduction) revealed that ARP is superior to EXT. Likewise, volumetric bone resorption was significantly higher in the control group (mean ± SD: EXT = -15.83% ± 4.48%, ARP = -8.36% ± 3.81%, P < 0.0001). Linear regression analyses revealed that baseline buccal bone thickness is a strong predictor of alveolar bone resorption in both groups. Interestingly, no significant differences in terms of soft tissue contour change were observed between groups. Additional bone augmentation to facilitate implant placement in a prosthetically acceptable position was deemed necessary in 48.1% of the EXT sites and only 11.5% of the ARP sites (P < 0.004). Assessment of perceived postoperative discomfort at each follow-up visit revealed a progressive decrease over time, which was comparable between groups. Although some extent of alveolar ridge remodeling occurred in both groups, ARP therapy was superior to EXT as it was more efficacious in the maintenance of alveolar bone and reduced the estimated need for additional bone augmentation at the time of implant placement (ClinicalTrials.gov NCT01794806).
Assuntos
Perda do Osso Alveolar , Aumento do Rebordo Alveolar , Perda do Osso Alveolar/prevenção & controle , Processo Alveolar/diagnóstico por imagem , Processo Alveolar/cirurgia , Transplante Ósseo , Humanos , Extração Dentária , Alvéolo Dental/cirurgiaRESUMO
Sheep increased their water intake in proportion to the amount of protein-free, isosmotic fluid that was removed from their blood by ultrafiltration. This behavioral response to hypovolemia was eliminated by crushing the left atrial appendage of the heart. The surgical maneuver had no effect on basal water intake or on the drinking response to a salt load. These findings suggest that left atrial stretch receptors, which influence secretion of antidiuretic hormone when stimulated, may also play an important role in mediating thirst during hypovolemia.
Assuntos
Volume Sanguíneo , Comportamento de Ingestão de Líquido/fisiologia , Coração/inervação , Mecanorreceptores/fisiologia , Animais , Pressão Sanguínea , Proteínas Sanguíneas/metabolismo , Feminino , Taxa de Filtração Glomerular , Coração/fisiologia , Sexo , Ovinos , Sódio/sangue , Sede/fisiologiaRESUMO
Diabetes mellitus is considered an indicator of poor prognosis for acute ankle fractures, but this risk may be specific to an identifiable subpopulation. We retrospectively reviewed 42 patients with both diabetes mellitus and an acute, closed, rotational ankle fracture. Patients were individually matched to controls by age, gender, fracture type, and surgical vs non-surgical treatment. Outcomes were major complications during the first six months of treatment. We contrasted secondarily 21 diabetic patients with and 21 without diabetic comorbidities. Diabetic patients and controls did not differ significantly in total complication rates. More diabetic patients required long-term bracing. Diabetic patients without comorbidities had complication rates equal to their controls. Diabetic patients with comorbidities had complications at a higher rate (ten patients; 47%) than matched controls (three patients; 14%, p = 0.034). A history of Charcot neuroarthropathy led to the highest rates of complication. An increased risk of complications in diabetic patients with closed rotational fractures of the ankle are specific to a subpopulation with identifiable related comorbidities.
Assuntos
Traumatismos do Tornozelo/complicações , Complicações do Diabetes/complicações , Fraturas Ósseas/complicações , Adulto , Idoso , Traumatismos do Tornozelo/cirurgia , Traumatismos do Tornozelo/terapia , Feminino , Fixação de Fratura/métodos , Fraturas Ósseas/cirurgia , Fraturas Ósseas/terapia , Humanos , Assistência de Longa Duração , Masculino , Pessoa de Meia-Idade , Aparelhos Ortopédicos , Complicações Pós-Operatórias , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Infecção dos Ferimentos/etiologiaRESUMO
Mean arterial blood pressure was measured over a 24-hour period from the femoral artery of conscious, unrestrained spontaneously hypertensive rats. Oral administration of the angiotensin converting enzyme inhibitor CGS 16617 significantly lowered mean arterial pressure. In contrast, both the thromboxane synthase inhibitor CGS 12970 and the thromboxane receptor antagonist BM 13505 lacked an antihypertensive action in the spontaneously hypertensive rat. When administered concurrently, the thromboxane synthase inhibitor CGS 12970 potentiated the antihypertensive action of the angiotensin converting enzyme inhibitor CGS 16617. This effect was not observed with the thromboxane receptor antagonist BM 13505. In addition to CGS 16617, CGS 12970 also potentiated the hypotensive effect of two structurally dissimilar angiotensin converting enzyme inhibitors, benazapril HCL and captopril. Indomethacin blocked the thromboxane synthase inhibition-induced potentiation of the antihypertensive action of angiotensin converting enzyme inhibitors. The thromboxane synthase inhibitor CGS 12970 had no effect on the hypotension induced by hydralazine, indicating that the hypotension is not a nonspecific action related to the fall in blood pressure. These results may suggest that converting enzyme inhibition augments the levels and actions of a hormone that stimulates prostaglandin formation. It is well established that thromboxane synthase inhibitors eliminate the formation of the vasoconstrictor thromboxane A2 and allow reorientation of eicosanoid production toward the formation of vasodilating prostaglandins, which could enhance the antihypertensive action of angiotensin converting enzyme inhibitors.
Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Piridinas/farmacologia , Tromboxano-A Sintase/antagonistas & inibidores , Animais , Benzazepinas/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Sinergismo Farmacológico , Hidralazina/farmacologia , Indometacina/farmacologia , Rim/efeitos dos fármacos , Fenilacetatos/farmacologia , Ratos , Ratos Endogâmicos SHR , Sulfonamidas/farmacologiaRESUMO
A four-step synthesis of 2-chlorodopamine (2b) is presented as well as methods for the syntheses of the N-methyl, ethyl, and n-propyl analogues (2c-e). Compounds 2b and 2c were essentially equipotent to dopamine for increasing renal blood flow in anesthetized dogs that had been treated with the alpha-adrenergic antagonist phenoxybenzamine. The increases in renal blood flow were blocked by the DA1 antagonist (R)-(+)-8-chloro-2,3,4,5-tetrahydro-3-methyl-5-phenyl-1H-3-benzazepine. Compounds 2d and 2e were significantly less potent than dopamine in the same model; the increases in renal blood flow were attenuated by propranolol and blocked by a combination of propranolol and (R)-(+)-8-chloro-2,3,4,5-tetrahydro-3-methyl-5-phenyl-1H-3-benzazepine. The significance of an o-chloro substituent on dopamine analogues for the activation of the DA1 receptor is briefly discussed.
Assuntos
Dopamina/análogos & derivados , Circulação Renal/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Animais , Benzazepinas/farmacologia , Fenômenos Químicos , Química , Cães , Dopamina/síntese química , Dopamina/farmacologia , Feminino , Rim/irrigação sanguínea , Masculino , Propranolol/farmacologia , Relação Estrutura-AtividadeRESUMO
PURPOSE: To evaluate in rhesus monkeys parapapillary chorioretinal atrophy in chronic high-pressure glaucoma and the effects of age, atherosclerosis, and chronic arterial hypertension in a prospective, planned study. METHODS: Seventy-six eyes from 38 monkeys were studied. First, experimental atherosclerosis and chronic arterial hypertension were produced in 24 animals. Then experimental high-pressure glaucoma was produced by laser photocoagulation of the anterior chamber angle in 38 eyes from the 38 animals. Intraocular pressure measurements and fundus photography were serially performed. The photographs were morphometrically analyzed. RESULTS: In the glaucomatous eyes, area and frequency of beta zone of parapapillary atrophy were significantly (P < 0.0001) larger at the end of the study than at baseline. Area of beta zone was significantly (P < 0.0001) and negatively correlated with neuroretinal rim area. In an intraindividual intereye comparison, beta zone was significantly (P < 0.0001) larger in the glaucomatous than in the contralateral nonglaucomatous eyes. Increase of beta zone and loss of neuroretinal rim were independent of presence and size of beta zone at start of the study. Beta zone was significantly (P = 0.036) greater in older than in younger monkeys; however, atherosclerosis-arterial hypertension had no significant influence on frequency and size of beta zone. Area and frequency of alpha zone showed no significant change between baseline values and those at the end of study. CONCLUSIONS: In experimental chronic high-pressure glaucoma in monkeys, beta zone of parapapillary atrophy was positively correlated with glaucomatous optic nerve damage. This confirms previous biomorphometric and histomorphometric studies on patients with glaucoma. In chronic experimental high-pressure glaucoma, neuroretinal rim loss and an increase of beta zone may be independent of preexisting parapapillary atrophy. Increase of beta zone may be independent of concomitant atherosclerosis-arterial hypertension.
Assuntos
Doenças da Coroide/etiologia , Glaucoma de Ângulo Aberto/complicações , Pressão Intraocular , Atrofia Óptica/etiologia , Disco Óptico/patologia , Doenças Retinianas/etiologia , Envelhecimento , Animais , Doenças da Coroide/patologia , Doença Crônica , Doença da Artéria Coronariana/complicações , Dieta Aterogênica , Modelos Animais de Doenças , Feminino , Fundo de Olho , Hipertensão/complicações , Fotocoagulação a Laser , Macaca mulatta , Masculino , Atrofia Óptica/patologia , Estudos Prospectivos , Doenças Retinianas/patologiaRESUMO
We analyzed data on 1,108 patients (1,229 eyes) with various types of retinal vein occlusion. Retinal vein occlusion was classified into six distinct clinical types: (I) nonischemic and (II) ischemic central retinal vein occlusion, (III) nonischemic and (IV) ischemic hemicentral retinal vein occlusion, and (V) major and (VI) macular branch retinal vein occlusion. Retinal vein occlusion occurred more often in men than women. The age range of patients was between 14 and 92 years, with 570 of 1,108 patients (51%) 65 years or older; however, 99 of 620 (16%), 15 of 154 (10%), and 17 of 375 (5%) of the patients with central, hemicentral, and branch retinal vein occlusion, respectively, were younger than 45 years. The cumulative probability of developing a second episode of the same or a different type of retinal vein occlusion in the same eye was 0.9% within two years and 2.5% within four years, and in the fellow eye was 7.7% and 11.9%, respectively. The cumulative probability of conversion of nonischemic to ischemic central retinal vein occlusion at six months and 18 months was 13.2% and 18.6%, respectively, in persons 65 years of age or older and 6.7% and 8.1%, respectively, in persons 45 to 64 years of age.
Assuntos
Oclusão da Veia Retiniana/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Demografia , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Probabilidade , Recidiva , Oclusão da Veia Retiniana/classificação , Fatores de Risco , Distribuição por SexoRESUMO
PURPOSE: To investigate the effects of topical beta-blocker eyedrops on nocturnal arterial hypotension and heart rate and on visual field deterioration. METHODS: We prospectively investigated 275 white patients, 161 with glaucomatous optic neuropathy and 114 with nonarteritic anterior ischemic optic neuropathy, by 24-hour ambulatory blood pressure monitoring and diurnal curve of intraocular pressure, in addition to detailed ophthalmic evaluation. Of the patients with glaucomatous optic neuropathy, 131 had normal-tension glaucoma and 30 had primary open-angle glaucoma. Of the 275 patients, 114 were using topical beta-blocker eyedrops twice daily (76 with normal-tension glaucoma, 26 with primary open-angle glaucoma, and 12 with anterior ischemic optic neuropathy). RESULTS: Hourly average blood pressure data analyses showed overall a drop in blood pressure as well as heart rate during sleep, and a significantly greater drop in mean diastolic blood pressure (P = .009) at night in normal-tension glaucoma than in anterior ischemic optic neuropathy. Also, patients using beta-blocker eyedrops experienced a significantly greater percentage drop in diastolic blood pressure at night (P = .028), lower minimum nighttime diastolic blood pressure (P = .072), and lower minimum nighttime heart rate (P = .002) than did those not using them. In normal-tension glaucoma, eyes receiving beta-blocker eyedrops showed visual field progression significantly (P = .0003) more often than those not receiving beta-blockers. CONCLUSIONS: The findings of our studies, as well as those of others, suggest that any factor that increases nocturnal arterial hypotension is a potential risk factor in vulnerable individuals with glaucomatous optic neuropathy or anterior ischemic optic neuropathy. The present study suggests that the use of beta-blocker eyedrops, by aggravating nocturnal arterial hypotension and reducing the heart rate, may be a potential risk factor in susceptible individuals.
Assuntos
Antagonistas Adrenérgicos beta/efeitos adversos , Pressão Sanguínea/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Hipotensão/induzido quimicamente , Campos Visuais/efeitos dos fármacos , Antagonistas Adrenérgicos beta/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Betaxolol/efeitos adversos , Betaxolol/uso terapêutico , Pressão Sanguínea/fisiologia , Ritmo Circadiano , Feminino , Glaucoma de Ângulo Aberto/tratamento farmacológico , Glaucoma de Ângulo Aberto/fisiopatologia , Frequência Cardíaca/fisiologia , Humanos , Hipotensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Soluções Oftálmicas/efeitos adversos , Soluções Oftálmicas/uso terapêutico , Neuropatia Óptica Isquêmica/tratamento farmacológico , Neuropatia Óptica Isquêmica/fisiopatologia , Estudos Prospectivos , Timolol/efeitos adversos , Timolol/uso terapêutico , Campos Visuais/fisiologiaRESUMO
PURPOSE: To investigate in an exploratory study whether any evidence suggests that ophthalmic ischemic disorders, particularly of the optic nerve head, are associated with hearing loss. METHODS: We investigated prospectively 583 consecutive patients in eight primary ocular diagnostic groups for associated hearing loss: nonarteritic anterior ischemic optic neuropathy (n = 81), normal-tension glaucoma (n = 36), primary open-angle glaucoma (n = 138), other types of glaucoma (n = 142), ocular arterial occlusive disorders (n = 22), retinal vein occlusion (n = 89), ocular vasculitis (n = 42), and a miscellaneous group (n = 33). The patients and their relatives were questioned in detail for any evidence of hearing loss in the patients. RESULTS: In the logistic regression model, with presence or absence of hearing loss as the dependent variable and gender, age, and diagnosis as independent variables, gender (P = .003) and age (P<.0001) were found to be significantly associated with hearing loss. No significant association was found with any of the ophthalmic disease groups evaluated in this study. Whenever any significant association with any ophthalmic disease group was seen, this result could be explained by examination of the association between diagnosis and age, which showed a significant (P<.001) association. CONCLUSIONS: This study showed that there is a significant (P<.001) relationship between hearing loss and aging-the older the population, the higher the incidence of hearing loss-but the study showed that there is no association between hearing loss and ocular and optic nerve head ischemic disorders. The two represent unrelated and independent disorders.
Assuntos
Surdez/etiologia , Olho/irrigação sanguínea , Isquemia/complicações , Disco Óptico/irrigação sanguínea , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Criança , Surdez/epidemiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Análise de RegressãoRESUMO
We measured 24-hour ambulatory blood pressure monitoring and diurnal curve of the intraocular pressure in 166 white patients with anterior ischemic optic neuropathy, normal-tension glaucoma, primary open-angle glaucoma, and other optic nerve head disorders. Hourly average blood pressure data analyses showed a significant (P < .0001) decrease in mean systolic (26%) and diastolic (33%) blood pressure measurements at night. A significantly (P = .0028) lower nighttime mean diastolic blood pressure and a significantly (P = .0044) greater mean percentage decrease in diastolic blood pressure were noted in normal-tension glaucoma than in anterior ischemic optic neuropathy. Patients with arterial hypertension taking oral hypotensive therapy showed a significant association between progressive visual field deterioration and nocturnal hypotension, particularly in anterior ischemic optic neuropathy. Intraocular pressure showed no significant correlation with visual field deterioration in any of these conditions. Our findings suggest that nocturnal hypotension, in the presence of other vascular risk factors, may reduce the optic nerve head blood flow below a critical level, and thereby may play a role in the pathogenesis of anterior ischemic optic neuropathy and glaucomatous optic neuropathy; that is, nocturnal hypotension may be the final insult in a multifactorial situation. The same mechanisms may be true of a number of other ocular ischemic disorders. This finding opens a new dimension in the understanding and management of these visually disabling diseases.
Assuntos
Ritmo Circadiano/fisiologia , Hipotensão/complicações , Isquemia/etiologia , Disco Óptico/irrigação sanguínea , Adulto , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea/fisiologia , Feminino , Glaucoma de Ângulo Aberto/complicações , Humanos , Pressão Intraocular/fisiologia , Masculino , Pessoa de Meia-Idade , Doenças do Nervo Óptico/etiologia , Campos VisuaisRESUMO
PURPOSE: To evaluate long-term visual field outcome in primary open-angle glaucoma. METHODS: In this retrospective cohort study, 40 eyes of 40 patients with primary open-angle glaucoma with elevated intraocular pressure and a minimum of 8-year longitudinal series of visual fields were plotted with Goldmann perimeter. Eyes with any other ocular disease except cataract were excluded. Manual grid templates were used to quantify the visual fields. Linear regression was performed to estimate the rate of visual field decline. Pertinent clinical factors were evaluated for statistical association with the rate of decline. Long-term clinical outcome including visual acuity, rate of legal blindness, and rate of medical and surgical interventions was also measured. RESULTS: In the 40 eyes studied, with a mean follow-up of 14 years, the visual field score decreased at the rate of -1.5% per year. Overall, 68% showed significant decrease, and the rate of decrease among these eyes was -2.1% per year. Five eyes became legally blind from glaucoma; the cumulative rate of blindness from glaucoma was 19% at 22 years. Higher intraocular pressure and greater number of antiglaucoma medications on initial presentation were associated with faster and slower deterioration of visual field (compared with the average), respectively. CONCLUSIONS: With standard glaucoma therapy, the rate of visual field loss in primary open-angle glaucoma is slow. Lower intraocular pressure and more antiglaucoma medications are associated with slower visual field decline. Legal blindness from glaucoma is 19% over a follow-up of 22 years.
Assuntos
Glaucoma de Ângulo Aberto/metabolismo , Transtornos da Visão/metabolismo , Acuidade Visual/fisiologia , Campos Visuais , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Glaucoma de Ângulo Aberto/tratamento farmacológico , Glaucoma de Ângulo Aberto/fisiopatologia , Humanos , Pressão Intraocular , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Transtornos da Visão/fisiopatologia , Testes de Campo VisualRESUMO
Seasonal variation in the development of retinal vein occlusion in 1003 consecutive patients with various types of retinal vein occlusion was studied prospectively from 1973 to 1990. No seasonal variation in the onset of any type or combination of types of retinal vein occlusion was found. This refutes previous reports of such seasonal variation, which were based on small retrospective series.
Assuntos
Oclusão da Veia Retiniana/epidemiologia , Estações do Ano , Adulto , Fatores Etários , Idoso , Feminino , Humanos , Isquemia/complicações , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Oclusão da Veia Retiniana/etiologia , Fatores SexuaisRESUMO
The adenosine analogs [5'-N-ethylcarboxamideadenosine (NECA), 2-Chloro-adenosine (2-ClA), R-phenylisopropyladenosine (R-PIA), N6-cyclohexyl adenosine (CHA), and N6-cyclopentyladenosine (CPA)] produced both relaxation and contraction responses in isolated guinea-pig trachea. A concentration-related relaxation response was observed in trachea which were precontracted with either histamine or KC1. This response followed an order of analog potency that was indicative of the A2 receptor subtype (NECA greater than 2-ClA greater than R-PIA greater than CPA greater than CHA). Theophylline, an adenosine-receptor antagonist, blocked this relaxation response. In addition, a concentration-related contractile response was produced with adenosine analogs in those trachea that were not previously contracted. In contrast, the contractile response followed an analog potency indicative of the A1 receptor subtype (R-PIA greater than 2-ClA = CPA = CHA). This contractile response was not mediated by cholinergic, adrenergic or histaminergic receptors. 2-ClA induced a biphasic response, while NECA only relaxed these tissue under basal tone. Unlike the relaxation response, these contractile responses were not attenuated by theophylline, but were blocked by 1,3 dipropyl-8-(2 amino-4-chlorophenyl)xanthine (PACPX). These findings confirm the existence of two subpopulations of adenosine receptors in guinea pig trachealis muscle.
Assuntos
Adenosina/farmacologia , Músculo Liso/fisiologia , Receptores Purinérgicos/metabolismo , Adenosina/análogos & derivados , Animais , Cobaias , Técnicas In Vitro , Cinética , Masculino , Relaxamento Muscular/efeitos dos fármacos , Receptores Purinérgicos/classificação , Receptores Purinérgicos/efeitos dos fármacos , Relação Estrutura-Atividade , Traqueia/fisiologiaRESUMO
Atrial natriuretic factor (ANF) increases sodium (Na+) and water excretion 8-10 fold on repeated administration to anesthetized rats. SCH-23390 (80 micrograms/kg i.v.) and R-sulpiride (80 micrograms/kg i.v.), selective antagonists of dopamine receptors in the renal vasculature, inhibited diuresis and natriuresis induced by AP III and dopamine. These findings suggest that ANF exerts its effects on renal Na+ and water handling via a dopaminergic mechanism; however, changes in intrarenal hemodynamics secondary to dopamine receptor blockade may attenuate the actions of ANF.
Assuntos
Fator Natriurético Atrial/farmacologia , Diurese/efeitos dos fármacos , Natriurese/efeitos dos fármacos , Animais , Benzazepinas/farmacologia , Pressão Sanguínea , Dopamina/farmacologia , Frequência Cardíaca/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Rim/irrigação sanguínea , Masculino , Ratos , Ratos Endogâmicos , Receptores Dopaminérgicos/metabolismo , Sulpirida/farmacologia , Resistência Vascular/efeitos dos fármacosRESUMO
BACKGROUND: In this article, the authors determine the reproducibility of appropriateness ratings for cataract surgery between a multidisciplinary physician panel that convened and a multidisciplinary physician panel that completed ratings by mail. METHODS: Eighteen panelists, who constituted 2 distinct multidisciplinary panels, rated 2894 clinical scenarios as an appropriate, inappropriate, or uncertain indication to perform cataract surgery. Each panel's summary score for each scenario was calculated. Weighted kappa values were determined to assess the level of agreement between the ratings of the 2 panels. RESULTS: The panels had a substantial level of agreement overall, with a weighted kappa statistic of 0.64. There was agreement on about 68% of the scenarios, and serious disagreement, in which one panel rated an indication appropriate and the other rated it inappropriate, occurred in only 1% of the ratings. CONCLUSION: There was substantial agreement about the ratings by the 2 panels. The panel that convened rated fewer scenarios uncertain and more appropriate, suggesting the impact of group dynamics and face-to-face discussion on resolution of uncertainty.
Assuntos
Extração de Catarata , Tomada de Decisões , Distribuição de Qui-Quadrado , Intervalos de Confiança , Conferências de Consenso como Assunto , Técnica Delphi , Humanos , Reprodutibilidade dos TestesRESUMO
We examined a group of normal subjects to evaluate the tear film function by measuring reflex tear capacity using the Schirmer test without anesthetic, steady state tear flow using fluorophotometry, meibomian gland function based on gland drop-out, expressible lipid volume and viscosity, tear loss from evaporation, and tear osmolarity. We found the average tear flow to be 0.19 +/- 0.19 microliters/min, lower than previously measured. The average tear volume was also correspondingly less, 2.74 +/- 2.0 microliters. We found there was a decline associated with advancing age for all parameters except the decay constant and lipid volume. The highest correlations with aging were tear volume (-0.64), Schirmer test (-0.63), and tear osmolarity (0.59). Our results indicate that there is a decline in tear film function throughout life and that tear flow is considerably less than previously estimated.
Assuntos
Envelhecimento/fisiologia , Lágrimas/fisiologia , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Concentração Osmolar , Valores de Referência , Análise de RegressãoRESUMO
PURPOSE: To evaluate the confocal microscopic appearance of the tear film by correlating the interference pattern created by the lipid surface with physiologic measurements of tear function and with clinic diagnosis. METHODS: A series of 53 patients was examined with a battery of tests to evaluate the tear film and with confocal microscopy to evaluate the interference pattern created by the lipid surface of the tear film. Assessment of the tear-film appearance involved five nonparametric scales: degree of debris in the tear film, variability of the interference pattern over time, linearity of the interference pattern, number of dry spots seen, and relative thickness of the lipid layer. For 10 other subjects, the confocal appearance of the tear film and evaporation from the ocular surface was tested for before and after meibomian gland expression. RESULTS: The confocal appearance correlated with multiple physiologic variables and clinical diagnosis. Patients with seborrheic meiboman gland dysfunction had a thicker lipid layer, greater variability, and more debris than did patients with obstructive meibomiam gland dysfunction. After meibomian gland expression, lipid thickness and linearity increased, whereas pattern variability and evaporation decreased significantly. The mean reduction in evaporation was 48%. CONCLUSIONS: Confocal microscopy can be used to examine the tear film, and its appearance correlates significantly with physiologic variables in normal-individuals and in disease states. The confocal appearance of the lipid interference patterns and evaporation from the ocular surface are altered after lipid expression from meibomian glands.