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1.
Clin Infect Dis ; 77(7): 950-960, 2023 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-37338118

RESUMO

BACKGROUND: Patients with antibody deficiency respond poorly to coronavirus disease 2019 (COVID-19) vaccination and are at risk of severe or prolonged infection. They are given long-term immunoglobulin replacement therapy (IRT) prepared from healthy donor plasma to confer passive immunity against infection. Following widespread COVID-19 vaccination alongside natural exposure, we hypothesized that immunoglobulin preparations will now contain neutralizing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike antibodies, which confer protection against COVID-19 disease and may help to treat chronic infection. METHODS: We evaluated anti-SARS-CoV-2 spike antibody in a cohort of patients before and after immunoglobulin infusion. Neutralizing capacity of patient samples and immunoglobulin products was assessed using in vitro pseudovirus and live-virus neutralization assays, the latter investigating multiple batches against current circulating Omicron variants. We describe the clinical course of 9 patients started on IRT during treatment of COVID-19. RESULTS: In 35 individuals with antibody deficiency established on IRT, median anti-spike antibody titer increased from 2123 to 10 600 U/mL postinfusion, with corresponding increase in pseudovirus neutralization titers to levels comparable to healthy donors. Testing immunoglobulin products directly in the live-virus assay confirmed neutralization, including of BQ1.1 and XBB variants, but with variation between immunoglobulin products and batches.Initiation of IRT alongside remdesivir in patients with antibody deficiency and prolonged COVID-19 infection (median 189 days, maximum >900 days with an ancestral viral strain) resulted in clearance of SARS-CoV-2 at a median of 20 days. CONCLUSIONS: Immunoglobulin preparations now contain neutralizing anti-SARS-CoV-2 antibodies that are transmitted to patients and help to treat COVID-19 in individuals with failure of humoral immunity.


Assuntos
Anticorpos Neutralizantes , COVID-19 , Humanos , Glicoproteína da Espícula de Coronavírus , Vacinas contra COVID-19 , SARS-CoV-2 , Anticorpos Antivirais
2.
Am J Physiol Heart Circ Physiol ; 324(3): H293-H304, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36637971

RESUMO

Chronic stimulation of cardiac α1A-adrenergic receptors (α1A-ARs) improves symptoms in multiple preclinical models of heart failure. However, the translational significance remains unclear. Human engineered heart tissues (EHTs) provide a means of quantifying the effects of chronic α1A-AR stimulation on human cardiomyocyte physiology. EHTs were created from thin slices of decellularized pig myocardium seeded with human induced pluripotent stem cell (iPSC)-derived cardiomyocytes and fibroblasts. With a paired experimental design, EHTs were cultured for 3 wk, mechanically tested, cultured again for 2 wk with α1A-AR agonist A61603 (10 nM) or vehicle control, and retested after drug washout for 24 h. Separate control experiments determined the effects of EHT age (3-5 wk) or repeat mechanical testing. We found that chronic A61603 treatment caused a 25% increase of length-dependent activation (LDA) of contraction compared with vehicle treatment (n = 7/group, P = 0.035). EHT force was not increased after chronic A61603 treatment. However, after vehicle treatment, EHT force was increased by 35% relative to baseline testing (n = 7/group, P = 0.022), suggesting EHT maturation. Control experiments suggested that increased EHT force resulted from repeat mechanical testing, not from EHT aging. RNA-seq analysis confirmed that the α1A-AR is expressed in human EHTs and found chronic A61603 treatment affected gene expression in biological pathways known to be activated by α1A-ARs, including the MAP kinase signaling pathway. In conclusion, increased LDA in human EHT after chronic A61603 treatment raises the possibility that chronic stimulation of the α1A-AR might be beneficial for increasing LDA in human myocardium and might be beneficial for treating human heart failure by restoring LDA.NEW & NOTEWORTHY Chronic stimulation of α1A-adrenergic receptors (α1A-ARs) is known to mediate therapeutic effects in animal heart failure models. To investigate the effects of chronic α1A-AR stimulation in human cardiomyocytes, we tested engineered heart tissue (EHT) created with iPSC-derived cardiomyocytes. RNA-seq analysis confirmed human EHT expressed α1A-ARs. Chronic (2 wk) α1A-AR stimulation with A61603 (10 nM) increased length-dependent activation (LDA) of contraction. Chronic α1A-AR stimulation might be beneficial for treating human heart failure by restoring LDA.


Assuntos
Insuficiência Cardíaca , Células-Tronco Pluripotentes Induzidas , Humanos , Animais , Suínos , Agonistas Adrenérgicos/metabolismo , Agonistas Adrenérgicos/farmacologia , Agonistas Adrenérgicos/uso terapêutico , Contração Miocárdica , Células-Tronco Pluripotentes Induzidas/metabolismo , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/metabolismo , Miócitos Cardíacos/metabolismo , Receptores Adrenérgicos/metabolismo , Receptores Adrenérgicos/uso terapêutico , Receptores Adrenérgicos alfa 1/metabolismo
3.
Curr Treat Options Oncol ; 24(10): 1451-1471, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37561382

RESUMO

OPINION STATEMENT: Prostate cancer (PCa) is the second most diagnosed malignant neoplasm and is one of the leading causes of cancer-related death in men worldwide. Despite significant advances in screening and treatment of PCa, given the heterogeneity of this disease, optimal personalized therapeutic strategies remain limited. However, emerging predictive and prognostic biomarkers based on individual patient profiles in combination with computer-assisted diagnostics have the potential to guide precision medicine, where patients may benefit from therapeutic approaches optimally suited to their disease. Also, the integration of genotypic and phenotypic diagnostic methods is supporting better informed treatment decisions. Focusing on advanced PCa, this review discusses polygenic risk scores for screening of PCa and common genomic aberrations in androgen receptor (AR), PTEN-PI3K-AKT, and DNA damage response (DDR) pathways, considering clinical implications for diagnosis, prognosis, and treatment prediction. Furthermore, we evaluate liquid biopsy, protein biomarkers such as serum testosterone levels, SLFN11 expression, total alkaline phosphatase (tALP), neutrophil-to-lymphocyte ratio (NLR), tissue biopsy, and advanced imaging tools, summarizing current phenotypic biomarkers and envisaging more effective utilization of diagnostic and prognostic biomarkers in advanced PCa. We conclude that prognostic and treatment predictive biomarker discovery can improve the management of patients, especially in metastatic stages of advanced PCa. This will result in decreased mortality and enhanced quality of life and help design a personalized treatment regimen.

4.
J Opt Soc Am A Opt Image Sci Vis ; 40(8): 1563-1567, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37707112

RESUMO

It is well known that in free space propagations, Bessel-Gauss (BG) beams are non-diffractive, in the sense that over a finite distance the beam mainlobe does not spread. Non-diffraction beams have been found to offer advantages over diffractive beams, for example, in terms of power delivery. However, in random media, such as a turbulent atmosphere, the performance of BG beams is still an active area of research. For example, applying the extended Huygens-Fresnel (EHF) principle results in an intractable expression for the optical field and the average intensity. This work is concerned with finding a closed-form expression for the average intensity of BG beam propagating through weak and strong Kolmogorov turbulence under the quadratic structure function (QSF) assumption. This is achieved by considering the average intensity convolution integral of the free space intensity with the point spread function (PSF). This convolution integral is reduced to a one-dimensional integral that can be easily evaluated in closed form and plotted. Moreover, the beam root mean square (rms) width is also given in terms of one-dimensional integrals. The work presented can be used for assessing the utility of a BG beam for applications in emerging communication systems such as optical wireless communications (OWC).

5.
Thorax ; 77(11): 1088-1097, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-34853154

RESUMO

BACKGROUND: Risk factors for COPD in high-income settings are well understood; however, less attention has been paid to contributors of COPD in low-income and middle-income countries (LMICs) such as pulmonary tuberculosis. We sought to study the association between previous tuberculosis disease and COPD by using pooled population-based cross-sectional data in 13 geographically diverse, low-resource settings. METHODS: We pooled six cohorts in 13 different LMIC settings, 6 countries and 3 continents to study the relationship between self-reported previous tuberculosis disease and lung function outcomes including COPD (defined as a postbronchodilator forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) below the lower limit of normal). Multivariable regressions with random effects were used to examine the association between previous tuberculosis disease and lung function outcomes. RESULTS: We analysed data for 12 396 participants (median age 54.0 years, 51.5% male); 332 (2.7%) of the participants had previous tuberculosis disease. Overall prevalence of COPD was 8.8% (range 1.7%-15.5% across sites). COPD was four times more common among those with previous tuberculosis disease (25.7% vs 8.3% without previous tuberculosis disease, p<0.001). The adjusted odds of having COPD was 3.78 times higher (95% CI 2.87 to 4.98) for participants with previous tuberculosis disease than those without a history of tuberculosis disease. The attributable fraction of COPD due to previous tuberculosis disease in the study sample was 6.9% (95% CI 4.8% to 9.6%). Participants with previous tuberculosis disease also had lower prebronchodilator Z-scores for FEV1 (-0.70, 95% CI -0.84 to -0.55), FVC (-0.44, 95% CI -0.59 to -0.29) and the FEV1:FVC ratio (-0.63, 95% CI -0.76 to -0.51) when compared with those without previous tuberculosis disease. CONCLUSIONS: Previous tuberculosis disease is a significant and under-recognised risk factor for COPD and poor lung function in LMICs. Better tuberculosis control will also likely reduce the global burden of COPD.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Tuberculose Pulmonar , Estudos Transversais , Feminino , Volume Expiratório Forçado , Humanos , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Fatores de Risco , Espirometria , Tuberculose Pulmonar/epidemiologia , Capacidade Vital
6.
BMC Pulm Med ; 22(1): 445, 2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36437459

RESUMO

BACKGROUND: There is limited information on the patient's perspective of how biologic treatments impact their lives. We conducted a qualitative study to explore the patient's experience of being considered a super-responder from a quality of life perspective. METHODS: Patients with severe asthma identified as super-responders were invited to semi-structured interviews conducted online. Participants could bring a family member/friend to the interview. The interviews explored experiences of biologic treatment, were transcribed and underwent thematic analysis. RESULTS: Twenty-five participants took part in this study. Themes emerged on the impact of biologic treatment for participants and for their friends/family: (i) Words used to describe their often life-changing experiences and (ii) the positive changes noted. Biologic treatment stopped the disruption of family life and social life caused by exacerbations. Improvements in mental health were also noted. Marked individual variations in the way it affected their lives were noted. Most participants noticed improvements 2-3 months after starting their biologic, but some noticed improvement within a few days and others after 6 months. CONCLUSIONS: Super-responders reported profound but heterogeneous improvements following biologic treatment beyond asthma symptoms and exacerbations including important benefits to social and family life. Improvements may be underestimated as social and family benefits are not reliably measured in current studies with implications for health economic evaluations. Not all patients are super-responders, and excellent responses may be lost in group mean data in trials. Individual time course and response patterns need further elucidation to identify who will respond best to biologics.


Assuntos
Asma , Produtos Biológicos , Humanos , Qualidade de Vida , Asma/tratamento farmacológico , Pesquisa Qualitativa , Família/psicologia , Produtos Biológicos/uso terapêutico
7.
Int J Mol Sci ; 23(8)2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35457141

RESUMO

Neuroblastoma is the most common extracranial solid tumor of childhood, with heterogeneous clinical manifestations ranging from spontaneous regression to aggressive metastatic disease. The calcium-sensing receptor (CaSR) is a G protein-coupled receptor (GPCR) that senses plasmatic fluctuation in the extracellular concentration of calcium and plays a key role in maintaining calcium homeostasis. We have previously reported that this receptor exhibits tumor suppressor properties in neuroblastoma. The activation of CaSR with cinacalcet, a positive allosteric modulator of CaSR, reduces neuroblastoma tumor growth by promoting differentiation, endoplasmic reticulum (ER) stress and apoptosis. However, cinacalcet treatment results in unmanageable hypocalcemia in patients. Based on the bias signaling shown by calcimimetics, we aimed to identify a new drug that might exert tumor-growth inhibition similar to cinacalcet, without affecting plasma calcium levels. We identified a structurally different calcimimetic, AC-265347, as a promising therapeutic agent for neuroblastoma, since it reduced tumor growth by induction of differentiation, without affecting plasma calcium levels. Microarray analysis suggested biased allosteric modulation of the CaSR signaling by AC-265347 and cinacalcet towards distinct intracellular pathways. No upregulation of genes involved in calcium signaling and ER stress were observed in patient-derived xenografts (PDX) models exposed to AC-265347. Moreover, the most significant upregulated biological pathways promoted by AC-265347 were linked to RHO GTPases signaling. AC-265347 upregulated cancer testis antigens (CTAs), providing new opportunities for CTA-based immunotherapies. Taken together, this study highlights the importance of the biased allosteric modulation when targeting GPCRs in cancer. More importantly, the capacity of AC-265347 to promote differentiation of malignant neuroblastoma cells provides new opportunities, alone or in combination with other drugs, to treat high-risk neuroblastoma patients.


Assuntos
Hipocalcemia , Neuroblastoma , Cálcio/metabolismo , Cinacalcete/farmacologia , Humanos , Masculino , Neuroblastoma/tratamento farmacológico , Receptores de Detecção de Cálcio/metabolismo
8.
Bioessays ; 41(4): e1800247, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30919490

RESUMO

For decades, myxobacteria have been spotlighted as exemplars of social "wolf-pack" predation, communally secreting antimicrobial substances into the shared public milieu. This behavior has been described as cooperative, becoming more efficient if performed by more cells. However, laboratory evidence for cooperativity is limited and of little relevance to predation in a natural setting. In contrast, there is accumulating evidence for predatory mechanisms promoting "selfish" behavior during predation, which together with conflicting definitions of cooperativity, casts doubt on whether microbial "wolf-pack" predation really is cooperative. Here, it is hypothesized that public-goods-mediated predation is not cooperative, and it is argued that a holistic model of microbial predation is needed, accounting for predator and prey relatedness, social phenotypes, spatial organization, activity/specificity/transport of secreted toxins, and prey resistance mechanisms. Filling such gaps in our knowledge is vital if the evolutionary benefits of potentially costly microbial behaviors mediated by public goods are to be properly understood.


Assuntos
Antibacterianos/metabolismo , Myxococcales/citologia , Evolução Biológica , Modelos Biológicos , Fatores de Tempo
9.
BMC Pulm Med ; 21(1): 369, 2021 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-34775957

RESUMO

BACKGROUND: Research into the effects of asthma treatments on the extra-pulmonary symptoms of severe asthma is limited by the absence of a suitable questionnaire. The aim was to create a questionnaire suitable for intervention studies by selecting symptoms that are statistically associated with asthma pathology and therefore may improve when pathology is reduced. METHODS: Patients attending a specialist asthma clinic completed the 65-item General Symptom Questionnaire (GSQ-65), a questionnaire validated for assessing symptoms of people with multiple medically unexplained symptoms. Lung function (FEV1%) and cumulative oral corticosteroids (OCS) calculated from maintenance dose plus exacerbations were obtained from clinic records. Pathology was represented by the two components of a principal component analysis (PCA) of FEV1% and OCS. LASSO regression was used to select symptoms that had high coefficients with these two principal components and occurred frequently in severe asthma. RESULTS: 100 patients provided data. PCA revealed two components, one where FEV1% and OCS were inversely related and another where they were directly related. LASSO regression revealed 39 symptoms with non-zero coefficients on one or more of the two principal components from which 16 symptoms were selected for the GSQ-A on the basis of magnitude of coefficient and frequency. Asthma symptoms measured by asthma control questionnaires were excluded. The GSQ-A correlated 0.33 and - 0.34 (p = 0.001) with the two principal components. CONCLUSION: The GSQ-A assesses the frequency of 16 heterogenous non-respiratory symptoms that are associated with asthma severity using the statistical combination of FEV1% and OCS.


Assuntos
Asma/fisiopatologia , Indicadores Básicos de Saúde , Inquéritos e Questionários , Avaliação de Sintomas/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Volume Expiratório Forçado , Humanos , Masculino , Pessoa de Meia-Idade
10.
Chron Respir Dis ; 18: 14799731211043530, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34565203

RESUMO

BackgroundThe sensitivity of patient-reported outcomes (PROs) to detect the effects of treatment change depends on the match between the change in items of the PRO and the change that takes place in a sample of people. The aim of this study is to compare the sensitivity of different PROs in detecting changes following the initiation of biologic treatment in asthma. Methods: Patients starting a biologic treatment as part of clinical care completed the Asthma Control Questionnaire (ACQ-6), the Severe Asthma Questionnaire (SAQ and SAQ-global scores) and the EQ5D (EQ-5D-5L and EQ5D-VAS) at baseline. They completed the ACQ-6, SAQ, SAQ-global and a retrospective global rating of change (GRoC) scale at weeks 4, 8 and 16 and completed the EQ-5D-5L and EQ5D-VAS at week 16. The SAQ-global and EQ5D-VAS differ but both are single item 100-point questions. Sensitivity was measured by Cohen's D effect size at each of the three time points. Results: 110 patients were recruited. Depending on the time of assessment, effect size varied between 0.45 and 0.64 for the SAQ, between 0.50 and 0.77 for the SAQ-global; between 0.45 and 0.69 for ACQ-6; between 0.91 and 1.22 for GRoC; 0.32 for EQ-5D-5L and 0.49 for EQ5D-VAS. Conclusion: The sensitivity to change of a questionnaire varies with the time of measurement. The three asthma-specific prospective measures (SAQ, SAQ-global and ACQ-6) have similar sensitivity to change. The single-item EQ5D-VAS was less sensitive than the asthma specific measures and less sensitive than the single-item SAQ-global. The EQ-5D-5L was least sensitive.


Assuntos
Asma , Produtos Biológicos , Asma/tratamento farmacológico , Produtos Biológicos/uso terapêutico , Humanos , Medidas de Resultados Relatados pelo Paciente , Estudos Prospectivos , Psicometria , Qualidade de Vida , Estudos Retrospectivos , Inquéritos e Questionários
11.
Health Qual Life Outcomes ; 18(1): 336, 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33036615

RESUMO

BACKGROUND: The Severe Asthma Questionnaire (SAQ) is a health related quality of life (HRQoL) questionnaire validated for use in severe asthma. It is scored using the mean value of 16 items (SAQ score) in addition to a single item global rating of HRQoL (SAQ-global). The aim was to validate clinically relevant subscales using exploratory factor analysis (EFA). METHODS: The SAQ was completed, along with measures of asthma control and EQ5D-5L by patients attending six UK severe asthma centres. Clinical data were included in the analysis. EFA using principal axis factoring and oblimin rotation was used to achieve simple structure of data. RESULTS: 460 patients with severe asthma participated, 65% women, mean age 51 (16-83) years. A three factor solution achieved best fit and showed that the SAQ items formed three distinct but inter-correlated groups of items where items were grouped in a way that was consistent with item content. The three subscales were differentially associated with clinically relevant variables (lung function and mood). Males and females interpreted the question of night disturbance in different ways. CONCLUSIONS: This paper provides a template for best practice in the use of EFA when validating HRQoL subscales. The SAQ can be scored as three subscales with content reflecting three different constructs people with severe asthma use when making judgements about their lives. The subscale 'My Life' assesses the impact of severe asthma on different life activities, 'My Mind' assesses the perceived emotional impact and 'My Body' the impact of extra-pulmonary symptoms and side effects.


Assuntos
Asma/psicologia , Qualidade de Vida , Inquéritos e Questionários/normas , Asma/fisiopatologia , Análise Fatorial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
12.
Eur Respir J ; 52(1)2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29794132

RESUMO

The US Food and Drug Administration's procedure for scale validation requires a documented stepwise process of qualitative and quantitative data. The aim of this paper is to provide final quantitative validating data for the Severe Asthma Questionnaire (SAQ).The SAQ, Asthma Control Test, Mini Asthma Quality of Life Questionnaire and EQ-5D-5L were completed by 160 patients attending a severe asthma clinic; 51 patients completed the SAQ on two occasions for test-retest reliability analysis. The SAQ produces two scores, a SAQ score based on the average of 16 items and a SAQ-global score from a single 100-point global quality of life scale.Construct validity was demonstrated by factor analysis of the 16 items, convergent validity by correlations of >0.6 between the SAQ, SAQ-global and other questionnaires, and discriminant validity by the ability of the SAQ and SAQ-global to distinguish between different treatment levels. Test-retest reliability (intra-class correlation) was 0.93 for the SAQ and 0.93 for the SAQ-global, and the alpha coefficient for the SAQ was 0.93.The SAQ was developed using recommended qualitative and quantitative procedures for scale development, and can be used to gain insight into patients' perceptions of how severe asthma and its treatment affects their lives.


Assuntos
Asma/fisiopatologia , Qualidade de Vida , Inquéritos e Questionários , Adolescente , Adulto , Idoso , Análise Fatorial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medidas de Resultados Relatados pelo Paciente , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Adulto Jovem
14.
Health Qual Life Outcomes ; 16(1): 24, 2018 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-29374455

RESUMO

BACKGROUND: Previous research shows that existing asthma quality of life questionnaires fail to measure the burden of oral corticosteroids that can be used to treat severe asthma, and are therefore not fit for purpose for severe asthma according to the USA's Federal Drug Authority's (FDA) criteria for content validity. Patient input and documentation of that input is key to achieving content validity according to FDA guidelines. This paper describes the process of constructing a new questionnaire to measure the burden of asthma symptoms and burden of treatment in severe asthma, using criteria specified by the FDA. METHODS: A draft severe asthma questionnaire (SAQ) was constructed using qualitative input from severe asthma patients who took part in an earlier study. The aim of this study was to improve that draft questionnaire using a further group of patients. In four iterative focus groups, 16 people with severe asthma completed the draft questionnaire, discussed the wording and structure and suggested changes that were incorporated into the final version. RESULTS: The original intention to ask patients to identify whether problems were caused by asthma symptoms or side effects of medication was abandoned as the attribution of cause was found to be difficult and inconsistent. The recall period of 2 weeks was acceptable but fails to reflect the patients' desire to express the variability of severe asthma. Patients suggested improvements to the wording of the draft questionnaire, including splitting some items in two, combining two items in one, and changes to some of the words in individual items and the response scale. CONCLUSIONS: The final version of the questionnaire was substantially different from one constructed using only qualitative reports from patients about the quality of life deficits of severe asthma. Patients make a valuable contribution to the questionnaire if they are asked to comment and improve an initial draft and where patients are treated as partners in the process of questionnaire construction, rather than only as a source of information to experts who construct the questionnaire.


Assuntos
Asma/psicologia , Inquéritos Epidemiológicos , Participação do Paciente/métodos , Qualidade de Vida , Administração Oral , Corticosteroides/efeitos adversos , Adulto , Idoso , Asma/tratamento farmacológico , Comportamento Cooperativo , Feminino , Grupos Focais , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Índice de Gravidade de Doença , Adulto Jovem
15.
J Exp Biol ; 220(Pt 6): 1065-1071, 2017 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-28096429

RESUMO

Animals that use vocal signals to communicate often compensate for interference and masking from background noise by raising the amplitude of their vocalisations. This response has been termed the Lombard effect. However, despite more than a century of research, little is known how quickly animals can adjust the amplitude of their vocalisations after the onset of noise. The ability to respond quickly to increases in noise levels would allow animals to avoid signal masking and ensure their calls continue to be heard, even if they are interrupted by sudden bursts of high-amplitude noise. We tested how quickly singing male canaries (Serinus canaria) exhibit the Lombard effect by exposing them to short playbacks of white noise and measuring the speed of their responses. We show that canaries exhibit the Lombard effect in as little as 300 ms after the onset of noise and are also able to increase the amplitude of their songs mid-song and mid-phrase without pausing. Our results demonstrate high vocal plasticity in this species and suggest that birds are able to adjust the amplitude of their vocalisations very rapidly to ensure they can still be heard even during sudden changes in background noise levels.


Assuntos
Canários/fisiologia , Vocalização Animal , Animais , Feminino , Audição , Masculino , Ruído , Som
18.
Nat Rev Immunol ; 5(2): 171-8, 2005 02.
Artigo em Inglês | MEDLINE | ID: mdl-15688043

RESUMO

Somatic hypermutation of immunoglobulin genes occurs at both C.G pairs and A.T pairs. Mutations at C.G pairs are created by activation-induced deaminase (AID)-catalysed deamination of C residues to U residues. Mutations at A.T pairs are probably produced during patch repair of the AID-generated U.G lesion, but they occur through an unknown mechanism. Here, we compare the popular suggestion of nucleotide mispairing through polymerase error with an alternative possibility, mutation through incorporation of dUTP (or another non-canonical nucleotide).


Assuntos
Pareamento Incorreto de Bases/genética , DNA Polimerase Dirigida por DNA , Nucleotídeos de Desoxiuracil/genética , Hipermutação Somática de Imunoglobulina/genética , Adenina , Animais , Pareamento de Bases/genética , Humanos , Timina
19.
Psychiatr Q ; 87(4): 605-618, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-26687294

RESUMO

This study explored (1) the incidence of posttraumatic stress disorder (PTSD) resulting from past trauma among older patients with COPD and (2) whether PTSD and COPD severity would relate to psychiatric co-morbidity and health-related quality of life. Eighty-five older patients completed the Hospital Anxiety and Depression Scale, the Chronic Respiratory Questionnaire, the Posttraumatic Stress Diagnostic Scale and the Medical Outcomes Short Form 12. The results showed that 55, 39 and 6 % had no, partial and full-PTSD respectively. Partial least squares showed that PTSD was significantly correlated with COPD severity which in turn was significantly correlated with health-related quality of life and psychiatric co-morbidity. Mediational analysis showed that the emotional symptoms of COPD mediated between PTSD and the mental health functioning of health-related quality of life and between PTSD and depression. To conclude, PTSD from past trauma was related to the severity of COPD for older patients. In particular, it impacted on the elevated emotional arousal of COPD severity. In turn, COPD severity impacted on older patients' general psychological well-being and depression.


Assuntos
Trauma Psicológico/epidemiologia , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Idoso , Ansiedade/epidemiologia , Ansiedade/psicologia , Depressão/epidemiologia , Depressão/psicologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Trauma Psicológico/psicologia , Doença Pulmonar Obstrutiva Crônica/psicologia , Qualidade de Vida/psicologia , Índice de Gravidade de Doença , Transtornos de Estresse Pós-Traumáticos/psicologia , Inquéritos e Questionários , Reino Unido/epidemiologia
20.
Qual Life Res ; 24(3): 631-9, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25201169

RESUMO

BACKGROUND: People with severe asthma experience significant respiratory symptoms and suffer adverse effects of oral corticosteroids (OCS), including disturbed mood and physical symptoms. OCS impacts on health-related quality of life (HRQoL) have not been quantified. Asthma HRQoL scales are valid as outcome measures for patients requiring OCS only if they assess the deficits imposed by OCS. AIMS: The aim of this study was to compare the burden of disease and treatment in patients with severe asthma with items in eight asthma-specific HRQoL scales. METHODS: Twenty-three patients with severe asthma recruited from a severe asthma clinic were interviewed about the impact of their respiratory symptoms and the burden of their treatment. The domains from a thematic analysis of these interviews were compared with the items of eight asthma-specific HRQoL scales. RESULTS: In addition to the burden caused by symptoms, ten domains of OCS impact on HRQoL were identified: depression, irritability, sleep, hunger, weight, skin, gastric, pain, disease anxiety, and medication anxiety. Some patients experienced substantial HRQoL deficits attributed to OCS. Although all HRQoL scales include some OCS-relevant items, all eight scales fail to adequately assess the several types of burden experienced by some patients while on OCS. CONCLUSION: The burden of OCS in severe asthma is neglected in policy and practice because it is not assessed in outcome studies. Existing asthma HRQoL scales provide an overly positive estimation of HRQoL in patients with frequent exposure to OCS and underestimate the benefit of interventions that reduce OCS exposure. Changes to existing measurement procedures are needed.


Assuntos
Corticosteroides/efeitos adversos , Corticosteroides/uso terapêutico , Asma/tratamento farmacológico , Efeitos Psicossociais da Doença , Qualidade de Vida , Adulto , Idoso , Ansiedade/induzido quimicamente , Depressão/induzido quimicamente , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/induzido quimicamente , Dor , Pesquisa Qualitativa , Análise de Regressão , Transtornos do Sono-Vigília/induzido quimicamente , Inquéritos e Questionários
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