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1.
J Womens Health (Larchmt) ; 33(3): 364-370, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38190297

RESUMO

Background: Depression and vulvodynia are often comorbid. The onset of depression and vulvodynia may be immune and/or stress/environmentally induced. We explored whether vulvodynia, depression, or both occur in response to a Th1-mediated versus Th2-mediated immune response. Materials and Methods: We analyzed data from a case-control study of clinically confirmed vulvodynia and history of depression determined through structured clinical interviews. Immune dysregulation and inflammation were categorized based on the following self-reported conditions: rheumatoid arthritis, Sjogren's disease, scleroderma, systemic lupus erythematosus, inflammatory bowel disease, fibromyalgia, osteoarthritis, polycystic ovarian syndrome, diabetes mellitus, uterine fibroids, asthma, atopic dermatitis, and allergic rhinitis. Logistic regression analyses were adjusted for marital status, body mass index, age, and pack years. Results: Women with systemic immune dysregulation had higher odds of depression (adjusted odds ratio [aOR] = 1.61, confidence interval [95% CI]: 0.65-3.98), vulvodynia (aOR = 2.45, 95% CI: 1.00-5.96), and comorbid depression and vulvodynia (aOR = 4.93, 95% CI: 2.19-11.10) versus neither condition. Women reporting local immune dysregulation had similar odds of depression (aOR = 1.89, 95% CI: 0.99-3.59), vulvodynia (aOR = 2.12, 95% CI: 1.08-4.18), and comorbid depression and vulvodynia (aOR = 1.96, 95% CI: 0.98-3.90). Women with Th2 inflammation had similar odds of depression (aOR = 2.23, 95% CI: 1.05-4.77) and vulvodynia (aOR = 2.56, 95% CI: 1.20-5.49). Women with Th1 or Th2 inflammation had similar odds of comorbid depression and vulvodynia (aOR = 3.03, 95% CI: 1.48-6.19; aOR = 3.14, 95% CI: 1.49-6.60, respectively). Conclusions: Our results suggest that an imbalance of cytokines, indicated by the presence of one or more immune-related health conditions, is associated with an increased risk of vulvodynia and/or depression.


Assuntos
Vulvodinia , Feminino , Humanos , Vulvodinia/epidemiologia , Vulvodinia/etiologia , Depressão/epidemiologia , Estudos de Casos e Controles , Comorbidade , Inflamação/epidemiologia
2.
EBioMedicine ; 95: 104758, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37598461

RESUMO

BACKGROUND: Identifying novel epigenetic signatures associated with serum immunoglobulin E (IgE) may improve our understanding of molecular mechanisms underlying asthma and IgE-mediated diseases. METHODS: We performed an epigenome-wide association study using whole blood from Framingham Heart Study (FHS; n = 3,471, 46% females) participants and validated results using the Childhood Asthma Management Program (CAMP; n = 674, 39% females) and the Genetic Epidemiology of Asthma in Costa Rica Study (CRA; n = 787, 41% females). Using the closest gene to each IgE-associated CpG, we highlighted biologically plausible pathways underlying IgE regulation and analyzed the transcription patterns linked to IgE-associated CpGs (expression quantitative trait methylation loci; eQTMs). Using prior UK Biobank summary data from genome-wide association studies of asthma and allergy, we performed Mendelian randomization (MR) for causal inference testing using the IgE-associated CpGs from FHS with methylation quantitative trait loci (mQTLs) as instrumental variables. FINDINGS: We identified 490 statistically significant differentially methylated CpGs associated with IgE in FHS, of which 193 (39.3%) replicated in CAMP and CRA (FDR < 0.05). Gene ontology analysis revealed enrichment in pathways related to transcription factor binding, asthma, and other immunological processes. eQTM analysis identified 124 cis-eQTMs for 106 expressed genes (FDR < 0.05). MR in combination with drug-target analysis revealed CTSB and USP20 as putatively causal regulators of IgE levels (Bonferroni adjusted P < 7.94E-04) that can be explored as potential therapeutic targets. INTERPRETATION: By integrating eQTM and MR analyses in general and clinical asthma populations, our findings provide a deeper understanding of the multidimensional inter-relations of DNA methylation, gene expression, and IgE levels. FUNDING: US NIH/NHLBI grants: P01HL132825, K99HL159234. N01-HC-25195 and HHSN268201500001I.


Assuntos
Asma , Metilação de DNA , Feminino , Humanos , Criança , Masculino , Epigenoma , Estudo de Associação Genômica Ampla , Asma/genética , Imunoglobulina E , Ubiquitina Tiolesterase
3.
Front Immunol ; 14: 1080071, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36793728

RESUMO

Measurement of circulating immunoglobulin E (IgE) concentration is helpful for diagnosing and treating asthma and allergic diseases. Identifying gene expression signatures associated with IgE might elucidate novel pathways for IgE regulation. To this end, we performed a discovery transcriptome-wide association study to identify differentially expressed genes associated with circulating IgE levels in whole-blood derived RNA from 5,345 participants in the Framingham Heart Study across 17,873 mRNA gene-level transcripts. We identified 216 significant transcripts at a false discovery rate <0.05. We conducted replication using the meta-analysis of two independent external studies: the Childhood Asthma Management Program (n=610) and the Genetic Epidemiology of Asthma in Costa Rica Study (n=326); we then reversed the discovery and replication cohorts, which revealed 59 significant genes that replicated in both directions. Gene ontology analysis revealed that many of these genes were implicated in immune function pathways, including defense response, inflammatory response, and cytokine production. Mendelian randomization (MR) analysis revealed four genes (CLC, CCDC21, S100A13, and GCNT1) as putatively causal (p<0.05) regulators of IgE levels. GCNT1 (beta=1.5, p=0.01)-which is a top result in the MR analysis of expression in relation to asthma and allergic diseases-plays a role in regulating T helper type 1 cell homing, lymphocyte trafficking, and B cell differentiation. Our findings build upon prior knowledge of IgE regulation and provide a deeper understanding of underlying molecular mechanisms. The IgE-associated genes that we identified-particularly those implicated in MR analysis-can be explored as promising therapeutic targets for asthma and IgE-related diseases.


Assuntos
Asma , Hipersensibilidade , Imunoglobulina E , Humanos , Asma/genética , Hipersensibilidade/genética , Imunoglobulina E/sangue , Testes Imunológicos , Transcriptoma
4.
Genome Med ; 14(1): 112, 2022 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-36175932

RESUMO

BACKGROUND: Asthma is the most common chronic disease in children, occurring at higher frequencies and with more severe disease in children with African ancestry. METHODS: We tested for association with haplotypes at the most replicated and significant childhood-onset asthma locus at 17q12-q21 and asthma in European American and African American children. Following this, we used whole-genome sequencing data from 1060 African American and 100 European American individuals to identify novel variants on a high-risk African American-specific haplotype. We characterized these variants in silico using gene expression and ATAC-seq data from airway epithelial cells, functional annotations from ENCODE, and promoter capture (pc)Hi-C maps in airway epithelial cells. Candidate causal variants were then assessed for correlation with asthma-associated phenotypes in African American children and adults. RESULTS: Our studies revealed nine novel African-specific common variants, enriched on a high-risk asthma haplotype, which regulated the expression of GSDMA in airway epithelial cells and were associated with features of severe asthma. Using ENCODE annotations, ATAC-seq, and pcHi-C, we narrowed the associations to two candidate causal variants that are associated with features of T2 low severe asthma. CONCLUSIONS: Previously unknown genetic variation at the 17q12-21 childhood-onset asthma locus contributes to asthma severity in individuals with African ancestries. We suggest that many other population-specific variants that have not been discovered in GWAS contribute to the genetic risk for asthma and other common diseases.


Assuntos
Asma , Negro ou Afro-Americano , Negro ou Afro-Americano/genética , Alelos , Asma/genética , Asma/metabolismo , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Proteínas de Neoplasias/genética , Polimorfismo de Nucleotídeo Único , Proteínas Citotóxicas Formadoras de Poros
5.
ERJ Open Res ; 8(2)2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35769418

RESUMO

Introduction: Bronchodilator response (BDR) is a measurement of acute bronchodilation in response to short-acting ß2-agonists, with a heritability between 10 and 40%. Identifying genetic variants associated with BDR may lead to a better understanding of its complex pathophysiology. Methods: We performed a genome-wide association study (GWAS) of BDR in six adult cohorts with participants of European ancestry (EA) and African ancestry (AA) including community cohorts and cohorts ascertained on the basis of obstructive pulmonary disease. Validation analysis was carried out in two paediatric asthma cohorts. Results: A total of 10 623 EA and 3597 AA participants were included in the analyses. No single nucleotide polymorphism (SNP) was associated with BDR at the conventional genome-wide significance threshold (p<5×10-8). Performing fine mapping and using a threshold of p<5×10-6 to identify suggestive variants of interest, we identified three SNPs with possible biological relevance: rs35870000 (within FREM1), which may be involved in IgE- and IL5-induced changes in airway smooth muscle cell responsiveness; rs10426116 (within ZNF284), a zinc finger protein, which has been implicated in asthma and BDR previously; and rs4782614 (near ATP2C2), involved in calcium transmembrane transport. Validation in paediatric cohorts yielded no significant SNPs, possibly due to age-genotype interaction effects. Conclusion: Ancestry-stratified and ancestry-combined GWAS meta-analyses of over 14 000 participants did not identify genetic variants associated with BDR at the genome-wide significance threshold, although a less stringent threshold identified three variants showing suggestive evidence of association. A common definition and protocol for measuring BDR in research may improve future efforts to identify variants associated with BDR.

10.
Ann Allergy Asthma Immunol ; 127(1): 19-27, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33716149

RESUMO

OBJECTIVE: To summarize the current understanding of diagnostic and postdiagnostic evaluation of common variable immunodeficiency (CVID). DATA SOURCES: PubMed Central database. STUDY SELECTIONS: Original research articles and review articles from 2015 to 2020 including seminal articles that shaped the diagnostic and postdiagnostic evaluation of CVID were incorporated. This work focuses on initial diagnosis of CVID, genetic evaluations, and postdiagnostic assessment of respiratory, gastrointestinal, and hepatobiliary diseases including spleen and lymph node enlargement. RESULTS: CVID presents not only with frequent infections but also with noninfectious complications such as autoimmunity, gastrointestinal disease, chronic lung disease, granulomas, liver disease, lymphoid hyperplasia, splenomegaly, or malignancy. The risk of morbidity and mortality is higher in patients with CVID and noninfectious complications. Detailed diagnostic approaches, which may incorporate genetic testing, can aid characterization of individual CVID cases and shape treatment in some instances. Moreover, continued evaluation after CVID diagnosis is key to optimal management of this complex disorder. These postdiagnostic evaluations include pulmonary function testing, radiologic studies, and laboratory evaluations that may be conducted at frequencies determined by disease activity. CONCLUSION: Although the diagnosis can be achieved similarly in all patients with CVID, those with noninfectious complications have distinct concerns during clinical evaluation. State-of-the-art workup of CVID with noninfectious complications typically includes genetic analysis, which may shape precision therapy, and thoughtful application of postdiagnostic tests that monitor the presence and progression of disease in the myriad of tissues that may be affected. Even with recent advancements, knowledge gaps in diagnosis, prognosis, and treatment of CVID persist, and continued research efforts are needed.


Assuntos
Imunodeficiência de Variável Comum/diagnóstico , Autoimunidade , Imunodeficiência de Variável Comum/complicações , Imunodeficiência de Variável Comum/genética , Imunodeficiência de Variável Comum/imunologia , Gastroenteropatias/complicações , Humanos , Hepatopatias/complicações , Pneumopatias/complicações , Neoplasias/complicações , Prognóstico
11.
Cancer ; 126(12): 2829-2836, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32134515

RESUMO

BACKGROUND: Transgender individuals' cancer prevalence and transgender cancer survivors' health needs have received scarce attention. The current study compared transgender and cisgender individuals' cancer prevalence and described the health needs of transgender cancer survivors. METHODS: The authors used Behavioral Risk Factor Surveillance System data on 95,800 cisgender and transgender individuals who self-reported a cancer diagnosis. Using multiple logistic regression, they estimated cancer prevalence and calculated odds ratios with 95% confidence intervals of physical, psychological, overall health, and health behaviors of transgender survivors compared with cisgender survivors. RESULTS: After adjusting for confounders, transgender men had a significantly higher (>2-fold) number of cancer diagnoses compared with cisgender men, but not cisgender women. Cancer prevalence among gender nonconforming individuals and transgender women was not significantly different from that of cisgender men and cisgender women. Gender nonconforming survivors had significantly greater physical inactivity, heavy episodic alcohol use, and depression compared with cisgender men and cisgender women. Transgender men survivors were significantly more likely to report poor physical health and greater medical comorbidities and were less likely to report smoking compared with cisgender men and cisgender women. Transgender women survivors were significantly more likely to report diabetes compared with cisgender men and cisgender women and were more likely to report cardiovascular disease compared with cisgender women. CONCLUSIONS: Clinicians should be aware of the higher prevalence of cancer among transgender men and a potential survivorship bias among transgender individuals. Transgender survivors have considerable variation in their risk profile. Clinicians and health services can target gender nonconforming survivors' depression and health behaviors to improve survival and should address the complex comorbidities of transgender men and transgender women.


Assuntos
Sobreviventes de Câncer , Neoplasias/epidemiologia , Pessoas Transgênero , Adolescente , Adulto , Idoso , Sistema de Vigilância de Fator de Risco Comportamental , Sobreviventes de Câncer/psicologia , Sobreviventes de Câncer/estatística & dados numéricos , Doenças Cardiovasculares/epidemiologia , Estudos Transversais , Exercício Físico , Feminino , Humanos , Masculino , Saúde Mental , Pessoa de Meia-Idade , Prevalência , Qualidade de Vida , Pessoas Transgênero/psicologia , Pessoas Transgênero/estatística & dados numéricos , Estados Unidos/epidemiologia , Adulto Jovem
13.
Cancer ; 125(17): 3079-3085, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31106409

RESUMO

BACKGROUND: Adults with poor access to care are known to have worse quality of life (QOL). The purpose of the current study was to determine differences in cancer survivors' access to care by sexual orientation and to examine the association between access to care and QOL. METHODS: The current secondary data analysis used 4 years of Behavioral Risk Factor Surveillance System data regarding adult men and women who self-reported a history of cancer. Among the 70,524 cancer survivors, a total of 1931 self-identified as sexual minorities, defined as lesbian, gay, bisexual, or other nonheterosexual orientation. RESULTS: Sexual minority women had significantly more access deficits compared with heterosexual women (42.7% vs 28.0%; P < .0001), whereas men of different sexual orientations had similar access to care. Among sexual minority women, those with access deficits had higher odds of poor physical QOL compared with heterosexual women (odds ratio [OR], 2.0 [95% CI, 1.2-3.4] vs OR, 1.3 [95% CI, 1.2-1.5]), poor mental QOL (OR, 1.8 [95% CI, 1.1-3.1] vs OR, 1.5 [95% CI, 1.3-1.7]), and difficulties concentrating (OR, 2.0 [95% CI, 1.2-3.5] vs OR, 1.7 [95% CI, 1.4-1.9]). Sexual minority men with access deficits had greater odds of difficulty concentrating compared with heterosexual men (OR, 4.3 [95% CI, 2.0-9.3] vs OR, 1.5 [95% CI, 1.2-1.9]). Among men, sexual minority status increased the odds of poor mental QOL (OR, 1.49 [95% CI, 1.11-2.01]). CONCLUSIONS: Access to care among sexual minority cancer survivors needs improvement. Sexual minority women should be a focus of future research because their poor access to care more strongly relates to worse QOL.


Assuntos
Sobreviventes de Câncer , Acessibilidade aos Serviços de Saúde , Qualidade de Vida , Minorias Sexuais e de Gênero , Adolescente , Adulto , Idoso , Sistema de Vigilância de Fator de Risco Comportamental , Bissexualidade , Sobreviventes de Câncer/estatística & dados numéricos , Feminino , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Disparidades em Assistência à Saúde , Homossexualidade Feminina , Humanos , Masculino , Pessoa de Meia-Idade , Estados Unidos , Adulto Jovem
14.
Front Immunol ; 10: 2753, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31921101

RESUMO

Common variable immunodeficiency (CVID) is the most prevalent symptomatic primary immunodeficiency and comprises a group of disorders with similar antibody deficiency but a myriad of different etiologies, most of which remain undefined. The variable aspect of CVID refers to the approximately half of patients who develop non-infectious complications in addition to heightened susceptibility to infection. The pathogenesis of these complications is poorly understood and somewhat counterintuitive because these patients that are defined by their immune futility simultaneously have elevated propensity for autoimmune disease. There are numerous aspects of immune dysregulation associated with autoimmunity in CVID that have only begun to be studied. These findings include elevations of T helper type 1 and follicular helper T cells and B cells expressing low levels of CD21 as well as reciprocal decreases in regulatory T cells and isotype-switched memory B cells. Recently, advances in genomics have furthered our understanding of the fundamental biology underlying autoimmunity in CVID and led to precision therapeutic approaches. However, these genetic etiologies are also associated with clinical heterogeneity and incomplete penetrance, highlighting the fact that continued research efforts remain necessary to optimize treatment. Additional factors, such as commensal microbial dysbiosis, remain to be better elucidated. Thus, while recent advances in our understanding of CVID-associated autoimmunity have been exciting and substantial, these current scientific advances must now serve as building blocks for the next stages of discovery.


Assuntos
Autoimunidade , Imunodeficiência de Variável Comum/etiologia , Suscetibilidade a Doenças , Animais , Doenças Autoimunes/diagnóstico , Doenças Autoimunes/etiologia , Doenças Autoimunes/metabolismo , Doenças Autoimunes/terapia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Biomarcadores , Imunodeficiência de Variável Comum/diagnóstico , Imunodeficiência de Variável Comum/metabolismo , Imunodeficiência de Variável Comum/terapia , Gerenciamento Clínico , Predisposição Genética para Doença , Humanos , Imunofenotipagem , Microbiota , Linfócitos T/imunologia , Linfócitos T/metabolismo
15.
LGBT Health ; 5(1): 45-53, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29130791

RESUMO

PURPOSE: From studies conducted in Western countries (United States, United Kingdom, and Australia), we know that the sexual health of sexual minority women (SMW) differs in key ways from that of heterosexual women (HSW). To date, the sexual health of SMW living in the Middle East and North Africa region has not been studied. The purpose of this study was to compare the sexual health of SMW and HSW living in Lebanon. METHODS: SMW and HSW living in Lebanon (N = 95) completed an anonymous, self-administered survey. SMW's risk perceptions and health promoting and sexual behaviors were compared to those of HSW. We examined differences by sexual orientation by using t tests and Fisher's exact tests. RESULTS: The 45 SMW and 50 HSW had similar demographic characteristics. Significantly more SMW had heard of human papillomavirus, but only 22% of women from both groups knew of its association with abnormal Papanicolaou tests. Cervical cancer screening rates were similar in SMW and HSW, although remarkably low (42%) compared with rates in Western countries. Significantly more SMW (18%) reported difficulty with access to care than HSW (0%). Forty-four percent of SMW reported discomfort in disclosing their sexual orientation to their healthcare provider and 61% reported that healthcare providers lacked sensitivity toward lesbian, gay, bisexual, and transgender needs. Unwanted sexual contact occurred more frequently in SMW (53%) than HSW (23%). CONCLUSION: The sexual health of women is affected by sociocultural factors. SMW living in Lebanon have unique health needs that should be addressed within their sociocultural context.


Assuntos
Comportamento Sexual , Saúde Sexual , Adolescente , Adulto , Estudos Transversais , Feminino , Comportamentos Relacionados com a Saúde , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Líbano , Pessoa de Meia-Idade , Minorias Sexuais e de Gênero/psicologia , Infecções Sexualmente Transmissíveis/prevenção & controle , Infecções Sexualmente Transmissíveis/psicologia , Adulto Jovem
16.
PLoS One ; 6(7): e21607, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21789173

RESUMO

In hyperpolarized xenon magnetic resonance imaging (HP (129)Xe MRI), the inhaled spin-1/2 isotope of xenon gas is used to generate the MR signal. Because hyperpolarized xenon is an MR signal source with properties very different from those generated from water-protons, HP (129)Xe MRI may yield structural and functional information not detectable by conventional proton-based MRI methods. Here we demonstrate the differential distribution of HP (129)Xe in the cerebral cortex of the rat following a pain stimulus evoked in the animal's forepaw. Areas of higher HP (129)Xe signal corresponded to those areas previously demonstrated by conventional functional MRI (fMRI) methods as being activated by a forepaw pain stimulus. The percent increase in HP (129)Xe signal over baseline was 13-28%, and was detectable with a single set of pre and post stimulus images. Recent innovations in the production of highly polarized (129)Xe should make feasible the emergence of HP (129)Xe MRI as a viable adjunct method to conventional MRI for the study of brain function and disease.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Imageamento por Ressonância Magnética , Sensação/efeitos dos fármacos , Xenônio/farmacologia , Xenônio/farmacocinética , Animais , Mapeamento Encefálico , Masculino , Estimulação Física , Ratos , Ratos Sprague-Dawley , Xenônio/administração & dosagem , Isótopos de Xenônio
17.
Respir Physiol Neurobiol ; 169(1): 44-9, 2009 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-19664729

RESUMO

We measured regional ventilation at 1l above functional residual capacity (FRC+1L) and total lung capacity (TLC) in three normal subjects and four elite breath-hold divers, and above TLC after glossopharyngeal insufflation (TLC+GI) in the divers. Hyperpolarized (3)He MRI was used to map the local ventilation per unit volume over the entire lung. At TLC and above, there was markedly increased regional ventilation of the lungs in the pericardial region compared with the relatively uniform ventilation throughout the rest of the lung. The distribution of fractional ventilation regionally was relatively uniform at FRC+1L, with a small non-gravitational cephalocaudal gradient of specific ventilation in the supine posture. Our observations at high lung volumes are consistent with the effect of high pleural tension in the concave pericardial region, which promotes expansion of the subjacent lung, leading to a higher local effective compliance and a higher specific ventilation.


Assuntos
Mergulho/fisiologia , Pulmão/fisiologia , Mecânica Respiratória/fisiologia , Capacidade Pulmonar Total/fisiologia , Adulto , Análise de Variância , Feminino , Capacidade Residual Funcional/fisiologia , Hélio , Humanos , Isótopos , Pulmão/anatomia & histologia , Imageamento por Ressonância Magnética/métodos , Masculino , Adulto Jovem
18.
Acad Radiol ; 15(6): 799-808, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18486015

RESUMO

RATIONALE AND OBJECTIVES: Application of a previously developed model-based algorithm on hyperpolarized (HP) (3)He magnetic resonance (MR) dynamic projection images of phantoms was extended to investigate the utility of HP (3)He MR imaging (MRI) in quantifying airway caliber changes associated with asthma. MATERIALS AND METHODS: Airways of seven volunteers were imaged and measured using HP (3)He MRI and multidetector-row computed tomography (MDCT) before and after a methacholine (MCh) challenge. MDCT data were obtained at functional residual capacity and 1 L above functional residual capacity. RESULTS: Comparison of the resultant data showed that HP (3)He MRI did not match MDCT in measuring the ratios of airway calibers before and after the MCh challenge in 37% to 43% of the airways from the first six generations at the two lung volumes tested. However, MDCT did yield the observation that 49% to 69% of these airways displayed bronchodilation following MCh challenge. CONCLUSION: The current implementation of HP (3)He MRI did not match the MCh-induced postchallenge-to-prechallenge airway caliber ratios as measured with MDCT. Elevated parenchymal tethering due to bronchoconstriction-induced hyperinflation was proposed as a possible explanation for this airway dilation.


Assuntos
Asma/fisiopatologia , Hélio , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X/métodos , Administração por Inalação , Adulto , Algoritmos , Brônquios/fisiopatologia , Feminino , Capacidade Residual Funcional , Humanos , Aumento da Imagem/métodos , Isótopos , Masculino , Pessoa de Meia-Idade , Intensificação de Imagem Radiográfica/métodos , Testes de Função Respiratória , Traqueia/fisiopatologia
19.
Med Phys ; 33(6): 1643-53, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16872072

RESUMO

Hyperpolarized (HP) 3He MRI is an emerging tool in the diagnosis and evaluation of pulmonary diseases involving bronchoconstriction, such as asthma. Previously, airway diameters from dynamic HP 3He MR images of the lung were assessed manually and subjectively, and were thus prone to uncertainties associated with human error and partial volume effects. A model-based algorithm capable of fully utilizing pixel intensity profile information and attaining subpixel resolution has been developed to measure surrogate airway diameters from HP 3He MR static projection images of plastic tubes. This goal was achieved by fitting ideal pixel intensity profiles for various diameter (6.4 to 19.1 mm) circular tubes to actual pixel intensity data. A phantom was constructed from plastic tubes of various diameters connected in series and filled with water mixed with contrast agent. Projection MR images were then taken of the phantom. The favorable performance of the model-based algorithm compared to manual assessment demonstrates the viability of our approach. The manual and algorithm approaches yielded diameter measurements that generally stayed within 1 x the pixel dimension. However, inconsistency of the manual approach can be observed from the larger standard deviations of its measured values. The method was then extended to HP 3He MRI, producing encouraging results at tube diameters characteristic of airways beyond the second generation, thereby justifying their application to lung airway imaging and measurement. Potential obstacles when measuring airway diameters using this method are discussed.


Assuntos
Anatomia Transversal/métodos , Análise dos Mínimos Quadrados , Pneumopatias/diagnóstico , Imageamento por Ressonância Magnética/métodos , Algoritmos , Brônquios/patologia , Simulação por Computador , Hélio , Humanos , Pneumopatias/patologia , Imagens de Fantasmas
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