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1.
Neuroimage ; 225: 117484, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33160085

RESUMO

We recently presented evidence indicating limited efficacy of custom-molded headcases in reducing head motion in two naturalistic experimental contexts - passive movie watching, and speaking in the scanner (Jolly et al., 2020). In a commentary on this work, Lynch et al (2020) present additional data that support the original findings of (Power et al., 2019) and raise several potential issues with our recent work. We appreciate the opportunity to address these criticisms and raise additional points that should be considered when interpreting these conflicting findings. We do not believe that their criticisms diminish the value of our work, but instead, along with this reply, help better elucidate the key factors researchers should consider to make the most informed choice about their own research protocols.


Assuntos
Imageamento por Ressonância Magnética , Filmes Cinematográficos , Humanos , Movimento (Física)
2.
Neuroimage ; 222: 117207, 2020 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-32745683

RESUMO

Effectively minimizing head motion continues to be a challenge for the collection of functional magnetic resonance imaging (fMRI) data. The use of individual-specific custom molded headcases is a promising solution to this issue, but there has been limited work to date. In the present work, we examine the efficacy of headcases in a larger group of participants engaged in naturalistic scanning paradigms including: long movie-watching scans (~20 to 45min) and a recall task that involved talking aloud inside the MRI. Unlike previous work, we find that headcases do not reliably reduce motion during movie viewing compared to alternative methods such as foam pillows or foam pillows plus medical tape. Surprisingly, we also find that motion is worse when participants talk aloud while wearing headcases. These differences appear to be driven by large, brief rotations of the head as well as translations in the z-plane as participants speak. Smaller, constant head movements appear equivalent with or without headcases. The largest reductions in head motion are observable when participants were situated with both foam pillows and medical tape. Altogether, this work suggests that in a healthy adult population, custom-molded headcases may provide limited efficacy in reducing head motion beyond existing tools available to researchers. We hope this work can help improve the quality of custom headcases, motivate the investigation of additional solutions, and provide additional information about head motion in naturalistic contexts.


Assuntos
Encéfalo/fisiologia , Neuroimagem Funcional/normas , Movimentos da Cabeça , Imageamento por Ressonância Magnética/normas , Restrição Física/normas , Adolescente , Adulto , Encéfalo/diagnóstico por imagem , Feminino , Atividades Humanas , Humanos , Masculino , Testes Neuropsicológicos , Adulto Jovem
3.
Am J Transplant ; 12(10): 2845-8, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22759079

RESUMO

Donor-specific HLA alloantibodies may cause acute and chronic antibody-mediated rejection (AMR) and significantly compromise allograft survival. The clinical relevance of antibodies directed against some HLA class II antigens, particularly HLA-DP, is less clear with conflicting reports on their pathogenicity. We report two patients with high levels of pretransplant donor-specific HLA-DP antibodies who subsequently developed recurrent acute AMR and graft failure. In both cases, there were no other donor-specific HLA alloantibodies, suggesting that the HLA-DP-specific antibodies may be directly pathogenic.


Assuntos
Rejeição de Enxerto/imunologia , Antígenos HLA-DP/imunologia , Transplante de Rim , Adulto , Humanos , Masculino
4.
Soc Cogn Affect Neurosci ; 16(8): 795-806, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-33501987

RESUMO

Multivariate neuroimaging analyses constitute a powerful class of techniques to identify psychological representations. However, not all psychological processes are represented at the same spatial scale throughout the brain. This heterogeneity is apparent when comparing hierarchically organized local representations of perceptual processes to flexible transmodal representations of more abstract cognitive processes such as social and affective operations. An open question is how the spatial scale of analytic approaches interacts with the spatial scale of the representations under investigation. In this article, we describe how multivariate analyses can be viewed as existing on a spatial spectrum, anchored by searchlights used to identify locally distributed patterns of information on one end, whole brain approach used to identify diffuse neural representations at the other and region-based approaches in between. We describe how these distinctions are an important and often overlooked analytic consideration and provide heuristics to compare these different techniques to choose based on the analyst's inferential goals.


Assuntos
Mapeamento Encefálico , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Humanos , Análise Multivariada , Neuroimagem
5.
J Med Genet ; 46(7): 425-30, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19366998

RESUMO

OBJECTIVE: Germline loss-of-function mutations in the SPRED1 gene have recently been identified in patients fulfilling the National Institutes of Health (NIH) diagnostic criteria for neurofibromatosis type 1 (NF1) but with no NF1 (neurofibromin 1) mutation found, suggesting a neurofibromatosis type 1-like syndrome. METHODS: 61 index cases with NF1 clinical diagnosis but no identifiable NF1 mutation were screened for SPRED1 mutation. RESULTS: We describe one known SPRED1 mutation (c.190C>T leading to p.Arg64Stop) and four novel mutations (c.637C>T leading to p.Gln213Stop, c.2T>C leading to p.Met1Thr, c.46C>T leading to p.Arg16Stop, and c.1048_1060del leading to p.Gly350fs) in five French families. Their NF1-like phenotype was characterised by a high prevalence of café-au-lait spots, freckling, learning disability, and an absence of neurofibromas and Lisch nodules in agreement with the original description. However, we did not observe Noonan-like dysmorphy. It is noteworthy that one patient with the p.Arg16Stop mutation developed a monoblastic acute leukaemia. CONCLUSIONS: In our series, SPRED1 mutations occurred with a prevalence of 0.5% in NF1 patients and in 5% of NF1 patients displaying an NF1-like phenotype. SPRED1 mutated patients did not display any specific dermatologic features that were not present in NF1 patients, except for the absence of neurofibromas that seem to be a specific clinical feature of NF1. The exact phenotypic spectrum and the putative complications of this NF1 overlapping syndrome, in particular haematological malignancies, remain to be further characterised. NIH diagnostic criteria for NF1 must be revised in view of this newly characterised Legius syndrome in order to establish a specific genetic counselling.


Assuntos
Mutação em Linhagem Germinativa , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas de Membrana/genética , Neurofibromatose 1/genética , Neurofibromina 1/genética , Proteínas Adaptadoras de Transdução de Sinal , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Análise Mutacional de DNA , Feminino , Dosagem de Genes , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem
6.
Science ; 271(5246): 209-12, 1996 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-8539622

RESUMO

PHO4, a transcription factor required for induction of the PHO5 gene in response to phosphate starvation, is phosphorylated by the PHO80-PHO85 cyclin-CDK (cyclin-dependent kinase) complex when yeast are grown in phosphate-rich medium. PHO4 was shown to be concentrated in the nucleus when yeast were starved for phosphate and was predominantly cytoplasmic when yeast were grown in phosphate-rich medium. The sites of phosphorylation on PHO4 were identified, and phosphorylation was shown to be required for full repression of PHO5 transcription when yeast were grown in high phosphate. Thus, phosphorylation of PHO4 by PHO80-PHO85 turns off PHO5 transcription by regulating the nuclear localization of PHO4.


Assuntos
Núcleo Celular/metabolismo , Quinases Ciclina-Dependentes/metabolismo , Ciclinas/metabolismo , Proteínas de Ligação a DNA , Proteínas Fúngicas/metabolismo , Proteínas de Transporte de Fosfato , Proteínas Repressoras , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Fatores de Transcrição/metabolismo , Sequência de Aminoácidos , Meios de Cultura , Citoplasma/metabolismo , Dipeptídeos/metabolismo , Regulação Fúngica da Expressão Gênica , Proteínas de Membrana Transportadoras/genética , Dados de Sequência Molecular , Mutação , Fosfatos/metabolismo , Fosforilação , Saccharomyces cerevisiae/genética
9.
Clin Chim Acta ; 446: 97-104, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25858546

RESUMO

BACKGROUND: Circulating PCSK9 levels are higher in women than men, in postmenopausal than premenopausal women, and in pregnant than non-pregnant women, suggesting that sex hormones may be related to PCSK9 levels. We have examined the relationship between serum estradiol (E2) and testosterone (T) and PCSK9, and the impact of E2 replacement therapy in women and T replacement and ablation therapy in men on circulating PCSK9. METHODS: We conducted a cross-sectional study to examine the correlation between serum T (in males) and E2 (in females) and serum PCSK9. We also conducted interventional studies to examine the effect of hormonal therapy on serum PCSK9 levels. RESULTS: In men, (1) serum T does not correlate with circulating PCSK9 or with LDLC in the basal state, (2) T replacement therapy does not have any effect on circulating PCSK9, and (3) T ablation therapy has mixed results. In women, (1) E2 correlates inversely with circulating PCSK9 and directly with serum LDLC, but (2) E2 replacement therapy does not have any effect on circulating PCSK9. CONCLUSIONS: We demonstrate differences between men and women in the relationship of their major sex hormones with circulating PCSK9. In men, circulating PCSK9 is not related to or affected by T except for a possible effect during T ablation therapy. In women, E2 is inversely related to circulating PCSK9 but the lack of effect of E2 therapy on circulating PCSK9 suggests that the E2-related differences in PCSK9 levels may be the result of differences in receptor-mediated PCSK9 clearance through E2-induced changes rather than production of PCSK9. The studies were registered with ClinicalTrials.gov NCT00848276.


Assuntos
Estradiol/sangue , Pró-Proteína Convertases/sangue , Serina Endopeptidases/sangue , Caracteres Sexuais , Testosterona/sangue , Adulto , Estudos de Coortes , Estudos Transversais , Intervenção Médica Precoce/tendências , Terapia de Reposição de Estrogênios/tendências , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pró-Proteína Convertase 9 , Testosterona/administração & dosagem
10.
Chest ; 104(2): 639-40, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8339669

RESUMO

We report the case of a 36-year-old woman who suffered tracheal dilatation and rupture despite careful monitoring of intracuff pressure. Surgical manipulation, postoperative mediastinitis, and bacterial staphylococcal tracheitis may be involved in the development of this complication.


Assuntos
Respiração Artificial/efeitos adversos , Traqueia/lesões , Adulto , Dilatação Patológica/etiologia , Feminino , Humanos , Intubação Intratraqueal/efeitos adversos , Mediastinite/etiologia , Complicações Pós-Operatórias , Radiografia , Respiração Artificial/métodos , Ruptura , Traqueia/diagnóstico por imagem , Ferimentos e Lesões/etiologia
11.
Chest ; 120(2): 437-43, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11502641

RESUMO

STUDY OBJECTIVES: To assess oxygen desaturation during activities and to evaluate the short-term effects of supplemental O(2) use in patients with severe COPD who do not qualify for long-term O(2) therapy. DESIGN: A double-blind, randomized, placebo-controlled trial. SETTING: Outpatients from the pulmonary diseases division of a tertiary-care university hospital. PATIENTS: Twenty patients with stable COPD with FEV(1)/FVC ratios of < 50%, FEV(1) levels < 55% of the predicted normal value, and PaO(2) levels of > 60 mm Hg when resting. INTERVENTIONS: Patients were initially evaluated with pulmonary function tests, blood gas analysis, and Doppler echocardiography, and they underwent the following three 6-min walking tests (WTs) in a random sequence: basal WT (BWT); WT while breathing compressed air (CAWT); and WT while breathing O(2) (O(2)WT). MEASUREMENTS AND RESULTS: The distance walked was recorded in meters. Dyspnea was measured by Borg scale measurement before and after the tests, and arterial oxygen saturation measured by pulse oximetry (SpO(2)) was continuously monitored. Results were analyzed by grouping patients in the following manner: desaturators (DSs) (ie, patients with a drop in SpO(2) of at least 5% and < 90% during the WT) vs nondesaturators (NDSs); and O(2) responders (ie, patients with an increase of at least 10% in the distance walked and/or a decrease of at least 3 points in Borg index score) vs nonresponders. During the BWT, 11 of 20 patients (55%) were defined as desaturators. During the O(2)WT, the SpO(2) remained at > 90% in every patient. The distance walked increased by 22% (p < 0.02), and dyspnea decreased 36% (p < 0.01) in DS patients. In NDS patients, O(2) administration reduced dyspnea by 47% (p < 0.001), but the distance walked did not improve. Responses were markedly different from one patient to another. No significant differences were noticed between the results of the BWT and CAWT in any of the groups. Thirteen O(2) responders did not differ from 7 nonresponders either in basal data or in desaturation measure during the BWT, except that all walking responders (five patients) were above the median of basal left ventricle performance. CONCLUSIONS: Most of the studied COPD patients desaturated during the BWT. O(2) administration avoided desaturation and could increase the distance walked and reduce dyspnea, but these effects were not related to walking desaturation in individual cases. Improvements were not a placebo effect. The therapeutic role of O(2) during activities in some patients with severe COPD needs to be individually assessed.


Assuntos
Pneumopatias Obstrutivas/fisiopatologia , Pneumopatias Obstrutivas/terapia , Oxigênio/administração & dosagem , Esforço Físico , Idoso , Método Duplo-Cego , Dispneia/prevenção & controle , Feminino , Humanos , Masculino , Oxigênio/análise , Oxigenoterapia , Caminhada
12.
Chest ; 88(3): 473-5, 1985 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-4028861

RESUMO

A 44-year-old woman was seen with the clinical and histologic picture of lymphangiomyomatosis syndrome. She also had dermatologic and neurologic stigmata of tuberous sclerosis. After the development of a recurring chylothorax, she had a downhill course unresponsive to dietary, bronchodilator, corticosteroid and progesterone therapy. In an open lung specimen, the search for steroid receptor for estrogen was positive. The discovery in this case of an estrogen receptor represents important evidence for establishing an association between tuberous sclerosis and lymphangiomyomatosis. Tamoxifen therapy and tetracycline pleurodesis were successful in stopping the progressive course and controlling the chylothorax.


Assuntos
Neoplasias Pulmonares/tratamento farmacológico , Linfangiomioma/tratamento farmacológico , Transtornos Linfoproliferativos/tratamento farmacológico , Pleura/efeitos dos fármacos , Tamoxifeno/uso terapêutico , Tetraciclina/uso terapêutico , Esclerose Tuberosa/complicações , Adesividade , Adulto , Quilotórax/etiologia , Quilotórax/terapia , Feminino , Humanos , Neoplasias Pulmonares/etiologia , Linfangiomioma/etiologia , Neoplasias Hormônio-Dependentes/tratamento farmacológico , Receptores de Estrogênio/análise
13.
Chest ; 111(3): 676-85, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9118708

RESUMO

STUDY OBJECTIVE: To define the impact of BAL data on the selection of antibiotics and the outcomes of patients with ventilator-associated pneumonia (VAP). DESIGN: Prospective observation and bronchoscopy with BAL, performed within 24 h of establishing a clinical diagnosis of a new episode of hospital-acquired VAP or progression of a prior episode of nosocomial pneumonia (NP). SETTING: A 15-bed medical and surgical ICU. PATIENTS: One hundred thirty-two patients hospitalized for more than 72 h, who were mechanically ventilated and had a new or progressive lung infiltrate plus at least two of the following three clinical criteria for VAP: abnormal temperature (> 38 degrees C or < 35 degrees C), abnormal leukocyte count (> 10,000/mm3 or < 3,000/mm3), purulent bronchial secretions. INTERVENTIONS: Bronchoscopy with BAL within 24 h of establishing a clinical diagnosis of VAP or progression of an infiltrate due to prior VAP or NP. All patients received antibiotics, 107 prior to bronchoscopy and 25 immediately after bronchoscopy. RESULTS: Sixty-five of the 132 patients were BAL positive (BAL[+]), satisfying a microbiologic definition of VAP (> 10(4) cfu/mL), while 67 were BAL negative (BAL[-]). The BAL(+) patients had no differences in mortality, prior antibiotic use, and demographic features when compared with the BAL(-) patients. More of the BAL(+) patients (38/65) satisfied all three clinical criteria of VAP than did BAL(-) patients (24/67) (p < 0.05). A total of 50 BAL(+) patients received antibiotic therapy prior to bronchoscopy, and when this prior therapy was adequate (n = 16), as defined by the results of BAL, then mortality was 38%, while if prior therapy was inadequate (n = 34), mortality was 91% (p < 0.001), and if no therapy was given (n = 15), mortality was 60%. When therapy changes were made after bronchoscopy, more patients (n = 42) received adequate therapy, but mortality in this group was comparable to mortality among those who continued to receive inadequate therapy (n = 23). A total of 46 of the 65 BAL(+) patients died, with 23 of these deaths occurring during the 48 h after the bronchoscopy, before BAL results were known. When BAL data became available, 37 of the 42 surviving patients received adequate therapy, but their mortality was comparable to the patients who continued to receive inadequate therapy. CONCLUSIONS: Patients with a strong clinical suspicion of VAP have a high mortality rate, regardless of whether BAL cultures confirm the clinical diagnosis of VAP. When adequate antibiotic therapy is initiated very early (ie, before performing bronchoscopy), mortality rate is reduced if this empiric therapy is adequate, compared to when this therapy is inadequate or no therapy is given. If adequate therapy is delayed until bronchoscopy is performed or until BAL results are known, mortality is higher than if it had been given at the time of first establishing a clinical diagnosis of VAP. When patients were changed from inadequate antibiotic therapy to adequate therapy, based on the results of BAL, mortality was comparable to those who continued to receive inadequate therapy. Thus, even if bronchoscopy can accurately define the microbial etiology of VAP, this information becomes available too late to influence survival.


Assuntos
Líquido da Lavagem Broncoalveolar/microbiologia , Infecção Hospitalar/diagnóstico , Pneumonia Bacteriana/diagnóstico , Pneumonia Bacteriana/tratamento farmacológico , Respiração Artificial/efeitos adversos , Idoso , Antibacterianos/uso terapêutico , Broncoscopia , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pneumonia Bacteriana/etiologia , Pneumonia Bacteriana/mortalidade , Estudos Prospectivos , Resultado do Tratamento
14.
Obstet Gynecol ; 67(3 Suppl): 59S-62S, 1986 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3080719

RESUMO

Six women who conceived after a diagnosis of premature ovarian failure are discussed. Two pregnancies occurred while the women were receiving conjugated estrogen therapy, two while taking oral contraceptives, and two women conceived spontaneously. The possible role of exogenous estrogens in sensitizing the granulosa cells to the effect of follicle-stimulating hormone and thereby inducing ovulation and conception in some women with premature ovarian failure is examined.


Assuntos
Menopausa Precoce , Menopausa , Gravidez , Adolescente , Adulto , Amenorreia/tratamento farmacológico , Amenorreia/etiologia , Animais , Neoplasias da Mama/complicações , Estrogênios/uso terapêutico , Feminino , Hormônio Foliculoestimulante/metabolismo , Células da Granulosa/metabolismo , Doença de Hodgkin/complicações , Humanos , Recém-Nascido , Leucemia Mieloide Aguda/complicações , Masculino , Ovário/fisiopatologia , Ratos , Síndrome de Turner/complicações
15.
Fertil Steril ; 30(6): 679-86, 1978 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-729828

RESUMO

An electron microscopic study was conducted on biopsies from 18 young hypospermatogenic patients. No signs of "tubular blockage" or "germinal disorganization" were found. The relationships between the different components of the germinal epithelium were comparable to those found in normal testes. Germ cells were often connected by cytoplasmic bridges and Sertoli cells by typical narrow junctions, which, in the case of very depleted tubules, were very extensive and of irregular outline owing to the interdigitations of the cells. Sertoli cells had normal cytologic characteristics and, contrary to the findings of other investigators in similar material, had apparently a normal amount of lipid droplets and microfilaments. In six cases, a large number of thick, banded collagen fibers substituted for the microfibrils usually found between the myoid cells in the tunica propia. The possible significance of these changes as a cause or as a consequence of the tubular changes is not yet clear.


Assuntos
Oligospermia/patologia , Testículo/ultraestrutura , Adulto , Biópsia , Colágeno , Citoplasma/ultraestrutura , Humanos , Masculino , Túbulos Seminíferos/ultraestrutura , Células de Sertoli/ultraestrutura
16.
Med Decis Making ; 18(3): 295-303, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9679994

RESUMO

Although practice guidelines suggest that postmenopausal women learn about the benefits and risks and consider their values when deciding about hormone therapy, the optimal decision-support method has not been established. In a randomized controlled trial, the authors compared the efficacy of a general educational pamphlet with that of a tailored decision aid. The pamphlet briefly summarized benefits, risks, and likely beneficiaries in general terms. The decision aid, delivered via booklet and audiotape, provided: detailed benefits and risks using functional terms and probabilities tailored to clinical risk; and steps for considering the issue in a woman's own situation, including a value-clarification exercise. Compared with the pamphlet group, the decision-aid group had statistically significant (p < 0.05) improvements in terms of realistic personal expectations of the benefits and risks, decisional conflict, and perceived acceptability of the intervention. Levels of general knowledge about the main benefits and risks were comparable for the two interventions. It is concluded that tailored decision aids prepare women for decision making better than do general pamphlets.


Assuntos
Técnicas de Apoio para a Decisão , Terapia de Reposição de Estrogênios , Educação de Pacientes como Assunto/métodos , Pós-Menopausa/efeitos dos fármacos , Pós-Menopausa/psicologia , Materiais de Ensino/normas , Idoso , Avaliação Educacional , Terapia de Reposição de Estrogênios/efeitos adversos , Feminino , Humanos , Pessoa de Meia-Idade , Folhetos , Aceitação pelo Paciente de Cuidados de Saúde , Fatores de Risco , Gravação em Fita/normas , Fatores de Tempo
17.
Patient Educ Couns ; 33(3): 267-79, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9731164

RESUMO

Although postmenopausal women are advised to consider their values when deliberating about potential benefits and risks of hormone therapy (HRT), feasible, effective methods of decision support in primary care have yet to be established. Using an explicit decision support framework, we developed a self-administered HRT decision aid and evaluated it in a before/after study of 94 women from six family practices. An audiotape guided women through an illustrated booklet including: detailed information about HRT benefits and risks tailored to a woman's clinical risk, and a values clarification exercise to promote informed decision making consistent with personal values. After using the decision aid participants: had better general knowledge and more realistic personal expectations of HRT benefits and risks; and, felt more certain, informed, clear about values, and supported in decision making. Women's values elicited in the clarification exercise were 84% accurate in discriminating between decisions. Women with polarized preferences at baseline did not change their minds, but were better informed. Changes in preferences occurred in the uncertain group, with equal numbers accepting or declining HRT. Most participants found the decision aid comprehensible, acceptable in length and pace, and balanced. Decision aids are useful in preparing women for decision making about this complex, personal issue.


Assuntos
Técnicas de Apoio para a Decisão , Terapia de Reposição Hormonal , Educação de Pacientes como Assunto/métodos , Pós-Menopausa/efeitos dos fármacos , Pós-Menopausa/psicologia , Idoso , Estudos de Avaliação como Assunto , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Terapia de Reposição Hormonal/efeitos adversos , Terapia de Reposição Hormonal/psicologia , Humanos , Pessoa de Meia-Idade , Materiais de Ensino
19.
Medicina (B Aires) ; 56(5 Pt 1): 472-8, 1996.
Artigo em Espanhol | MEDLINE | ID: mdl-9239882

RESUMO

Benzodiazepines are known to cause muscle hypotonia, but their effects on respiratory muscle function, particularly on diaphragm, have not yet been studied. Our aim was to look for any effect of lorazepam on respiratory muscle function in patients with chronic obstructive pulmonary disease (COPD). Nine stable COPD patients (mean +/- SD forced expiratory volume in one second (FEV1) 0.91 +/- 0.31 l) were included in the study. The following measurements were performed before and 1 hour after lorazepam administration (doses: 1.5 to 2 mg) by sublingual route: forced vital capacity (FVC), FEV1, maximal voluntary ventilation (MVV), arterial oxygen tension (PaO2), arterial carbon dioxide tension (PaCO2), minute ventilation (Ve), tidal volume (Vt), respiratory rate (f), inspiratory time/inspiratory plus expiratory time (Ti/Ttot)-, mean inspiratory flow (Vi), maximal inspiratory (MIP) and expiratory (MEP) pressures, maximal pleural pressure (Pplmax), transdiaphragmatic pressures (Pdi) and skeletal muscle strength and endurance. As expected, no change was noted in FVC, FEV1, FEV1/FVC (Table-1). Besides stability of expiratory flows, this denotes no change in collaboration in spite of the sedative effects of lorazepam. There was a 20% decrease in Ve, due to a Vt reduction and a small increase in PaCO2. These could be explained by the central effects of benzodiazepines. Skeletal muscle strength and endurance decreased significantly (22 and 50% respectively-Table 2), in accordance with the previously reported muscular actions of this pharmacological group. Respiratory muscle function parameters, MIP, MEP, MVV and Ppl showed significant reductions (10 to 20 per cent), as was the case with diaphragmatic function measured by Pdi (Muller maneuver with abdominal protrussion and maximal open-glottis expulsive maneuver) (Table 3). This study demonstrates that a single lorazepam dose reduces strength and endurance of respiratory muscle in chronic stable COPD patients.


Assuntos
Lorazepam/farmacologia , Pneumopatias Obstrutivas/fisiopatologia , Músculos Respiratórios/efeitos dos fármacos , Feminino , Humanos , Lorazepam/administração & dosagem , Pneumopatias Obstrutivas/tratamento farmacológico , Masculino , Ventilação Pulmonar/efeitos dos fármacos
20.
Medicina (B Aires) ; 51(1): 19-25, 1991.
Artigo em Espanhol | MEDLINE | ID: mdl-1921687

RESUMO

The histologic evidence of amiodarone pulmonary toxicity is interstitial pneumonia with foamy alveolar macrophages, which ultrastructurally show lamellar inclusion bodies due to lipid storage. Bronchoalveolar lavage (BAL) fluid findings include foamy macrophages, considered characteristic, and, in certain patients, differential cell counts suggestive of active alveolitis, giving rise to an immunologic explanation for its origin. The present study was undertaken in order to investigate the findings in BAL fluid in nontoxic patients taking amiodarone and to evaluate their clinical relevance. Eleven patients taking amiodarone chlorhydrate for severe ventricular arrhythmias (345 +/- 129 mg/day during 46 +/- 31 months and an accumulated dose of 440 +/- 337 g) and without clinical or radiological evidences of pulmonary toxicity, were clinically evaluated and studied by BAL. As shown in Table 1, cough and pulmonary rales were common findings (64% and 36% respectively), chest X-Rays were normal or indicative of cardiac failure and arterial blood gases showed slight hypoxemia (PaO2 83 +/- 10). As these are usual findings in advanced cardiac diseases, the patients were considered as having no amiodarone toxicity. BAL was done and the fluid obtained was processed for cytologic study. In every patient foamy macrophages were seen with light microscopy and lamellar bodies were detected by electron microscopy. In 5/10 evaluable patients BAL fluid cell count disclosed an increase in lymphocytes, leukocytes or both, indicative of alveolitis. This group of patient had lower PaO2 and PaO2/PAO2 than "non alveolitic" patients (76 +/- 9 mmHg vs 89 +/- 5 mmHg and 0.72 +/- 0.1 vs 0.85 +/- 0.08 - p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Amiodarona/efeitos adversos , Líquido da Lavagem Broncoalveolar/patologia , Pulmão/efeitos dos fármacos , Idoso , Idoso de 80 Anos ou mais , Arritmias Cardíacas/tratamento farmacológico , Broncoscopia , Feminino , Humanos , Pulmão/patologia , Macrófagos/efeitos dos fármacos , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade
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