Loss-of-function CFTR p.G970D missense mutation might cause congenital bilateral absence of the vas deferens and be associated with impaired spermatogenesis / 亚洲男科学杂志(英文版)

Congenital bilateral absence of the vas deferens (CBAVD) is observed in 1%-2% of males presenting with infertility and is clearly associated with cystic fibrosis transmembrane conductance regulator (CFTR) mutations. CFTR is one of the most well-known genes related to male fertility. The frequency of CFTR mutations or impaired CFTR expression is increased in men with nonobstructive azoospermia (NOA). CFTR mutations are highly polymorphic and have established ethnic specificity. Compared with F508Del in Caucasians, the p.G970D mutation is reported to be the most frequent CFTR mutation in Chinese patients with cystic fibrosis. However, whether p.G970D participates in male infertility remains unknown. Herein, a loss-of-function CFTR p.G970D missense mutation was identified in a patient with CBAVD and NOA. Subsequent retrospective analysis of 122 Chinese patients with CBAVD showed that the mutation is a common pathogenic mutation (4.1%, 5/122), excluding polymorphic sites. Furthermore, we generated model cell lines derived from mouse testes harboring the homozygous Cftr p.G965D mutation equivalent to the CFTR variant in patients. The Cftr p.G965D mutation may be lethal in spermatogonial stem cells and spermatogonia and affect the proliferation of spermatocytes and Sertoli cells. In spermatocyte GC-2(spd)ts (GC2) Cftr p.G965D cells, RNA splicing variants were detected and CFTR expression decreased, which may contribute to the phenotypes associated with impaired spermatogenesis. Thus, this study indicated that the CFTR p.G970D missense mutation might be a pathogenic mutation for CBAVD in Chinese males and associated with impaired spermatogenesis by affecting the proliferation of germ cells.

Actualización en fibrosis quística: uso de exacaftor/tezacaftor/ivacaftor/en pacientes con fibrosis quística port-trasplante pulmonar / Use of exacaftor/tezacaftor/ivacaftor in cystic patients post lung transplantation

El uso de moduladores de CFTR en pacientes con fibrosis quística post trasplante pulmonar es un tema todavía controversial. Varias publicaciones reportan los beneficios del modulador elexacaftor/tezacaftor/ivacaftor en los síntomas extrapulmonares de la fibrosis quística, especialmente enfermedad sinusal, síntomas gastrointestinales y diabetes. Un número alto de pacientes debe discontinuar el tratamiento por mala tolerancia, sin embargo, no se describen interacciones de importancia con el tratamiento inmunosupresor. Se debe considerar para su uso los riesgos versus beneficios en forma individual en cada paciente.

The use of CFTR modulators in patients with cystic fibrosis after lung transplantation is still a controversial issue. Several publications report the benefits of the use of the modulator elexacaftor/tezacaftor/ivacaftor on extrapulmonary symptoms of cystic fibrosis, especially sinus disease, gastrointestinal symptoms and diabetes. A high number of patients must discontinue treatment due to poor tolerance; however, no significant interactions with immunosuppressive treatment have been described. The individual risk-benefit of each patient should be considered for its use.

Fibrosis quística: patogenia bacteriana y moduladores del CFTR (regulador de conductancia transmembranal de la fibrosis quística) / Cystic fibrosis: bacterial pathogenesis and CFTR (cystic fibrosis transmembrane conductance regulator) modulators

Resumen La fibrosis quística es una enfermedad hereditaria autosómica recesiva que se origina por mutaciones en el gen regulador de conductancia transmembranal de la fibrosis quística (CFTR, cystic fibrosis transmembrane conductance regulator). El CFTR es una proteína que transporta iones a través de la membrana de las células epiteliales pulmonares. La pérdida de su función conlleva la producción de un moco pegajoso y espeso, donde se pueden establecer y adaptar diversos patógenos bacterianos que contribuyen a la pérdida gradual de la función pulmonar. En este artículo de revisión se dará evidencia de los mecanismos moleculares que utilizan Pseudomonas aeruginosa y Burkholderia cenocepacia para sobrevivir y persistir en el ambiente pulmonar. Adicionalmente, se describirán las nuevas estrategias de terapia a base de moduladores de la función del CFTR.

Abstract Cystic fibrosis is an autosomal recessive inherited disease caused by mutations in the cystic fibrosis transmembrane conductance regulator gene (CFTR). CFTR is a protein that transports ions across the membrane of lung epithelial cells. Loss of its function leads to the production of thick sticky mucus, where various bacterial pathogens can establish and adapt, contributing to the gradual loss of lung function. In this review, evidence of the molecular mechanisms used by Pseudomonas aeruginosa and Burkholderia cenocepacia to survive and persist in the pulmonary environment will be provided. Additionally, new therapeutic strategies based on CFTR function modulators will be described.

Función pulmonar: función pulmonar en fibrosis quística / Lung function in cystic fibrosis

La fibrosis quística (FQ) es una enfermedad hereditaria autosómica recesiva, causada por la mutación del gen que codifica la proteína CFTR (cystic fibrosis transmembrane conductance regulator), afecta varios órganos, pero la enfermedad pulmonar es la primera causa de morbimortalidad. El diagnóstico a través del screening neonatal (SNN) y los nuevos tratamientos moduladores del CFTR han aumentado el interés por pesquisar y monitorizar la función pulmonar antes del inicio de los síntomas para lograr un tratamiento adecuado y oportuno con una mejor calidad de vida. Existen numerosas formas de medir la función pulmonar según la edad, colaboración y recursos disponibles. En este artículo se resumen las pruebas clásicas y las más novedosas, como técnicas de imágenes, en la búsqueda de marcadores precoces de daño pulmonar, herramientas con los que cada centro de fibrosis quística debiera contar en la era de tratamientos moduladores del CFTR, que están cambiando el pronóstico de los pacientes con esta enfermedad.

Cystic fibrosis (CF) is an autosomal recessive inherited disease, caused by mutation of the gene encoding the CFTR protein (cystic fibrosis transmembrane conductance regulator), affects several organs, but lung disease is the first cause of morbidity and mortality. Diagnosis through neonatal screening (NNS) and new CFTR modulating treatments have increased interest in screening and monitoring lung function before the onset of symptoms to achieve adequate and timely treatment with a better quality of life. There are numerous ways to measure lung function based on age, collaboration, and available resources. This article summarizes the classic and the most innovative tests, which have emerged from imaging techniques in the search for early markers of lung damage, tools that each cystic fibrosis center should have in the era of CFTR modulating treatments, which are changing the prognosis of patients with this disease.

Research progress of cystic fibrosis and its therapies / 药学学报

Cystic fibrosis (CF) is a common and life-threatening autosomal recessive disorder in Caucasians populations. The disease is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. The absence of mature CFTR at the correct cellular location or dysfunction of CFTR proteins has been observed in CF patients. CF is frequently accompanied by a variety of complex complications, such as impairments in pulmonary functions, which may lead to successive infections and respiratory failure. Recently, with the understanding of the pathogenesis of CF, a wide array of therapeutic strategies for the treatment of CF has been designed. This review summarizes pathogenic mechanisms of CF, mechanisms of action of drugs, routes of administration, and new drug development as well as provides insights into the advanced treatment strategies for CF.

Novel mutation c.1210-3C > G in cis with a poly-T tract of 5T affects CFTR mRNA splicing in a Chinese patient with cystic fibrosis / 医学前沿

Cystic fibrosis (CF) is a rare autosomal recessive disease with only one pathogenic gene cystic fibrosis transmembrane conductance regulator (CFTR). To identify the potential pathogenic mutations in a Chinese patient with CF, we conducted Sanger sequencing on the genomic DNA of the patient and his parents and detected all 27 coding exons of CFTR and their flanking intronic regions. The patient is a compound heterozygote of c.2909G > A, p.Gly970Asp in exon 18 and c.1210-3C > G in cis with a poly-T of 5T (T5) sequence, 3 bp upstream in intron 9. The splicing effect of c.1210-3C > G was verified via minigene assay in vitro, indicating that wild-type plasmid containing c.1210-3C together with T7 sequence produced a normal transcript and partial exon 10-skipping-transcript, whereas mutant plasmid containing c.1210-3G in cis with T5 sequence caused almost all mRNA to skip exon 10. Overall, c.1210-3C > G, the newly identified pathogenic mutation in our patient, in combination with T5 sequence in cis, affects the CFTR gene splicing and produces nearly no normal transcript in vitro. Moreover, this patient carries a p.Gly970Asp mutation, thus confirming the high-frequency of this mutation in Chinese patients with CF.

Multi-disciplinary team of the treatment of bilateral lung transplantation for pediatric cystic fibrosis / 器官移植

Objective To improve the surgical efficacy of bilateral lung transplantation for pediatric cystic fibrosis through multi-disciplinary team (MDT). Methods Preoperative MDT consultation was delivered for a 10-year-old child with rare end-stage cystic fibrosis to establish the corresponding treatment protocol. Results The child was diagnosed with cystic fibrosis for 5 years, and the indication of lung transplantation were confirmed. After preoperative MDT consultation, bilateral lung transplantation via a Clam-shell incision was determined. The vital signs were maintained stable during operation. Postoperatively, ventilator-assisted ventilation, anti-infection, immunosuppression, acid suppression, prevention of stress ulceration and other treatments were delivered. Individualized treatment was given according to the characteristics of the child, and the child was well recovered. Conclusions Through preoperative MDT consultation, lung transplantation yields satisfactory surgical efficacy in treating pediatric cystic fibrosis and lowers the risk of postoperative complications, which deserves application in clinical practice.

A influência da idade e do genótipo sobre os níveis de cloreto do suor em uma população pediátrica com fibrose cística no estado da Bahia / The influence of age and genotype on sweat chloride levels in a pediatric population with cystic fibrosis in the state of Bahia

Introdução: a fibrose cística é a doença autossômica recessiva mais comum em populações caucasianas e a sua etiologia está associada a variantes patogênicas no gene CFTR. O teste do suor é considerado o padrão ouro para o diagnóstico dessa enfermidade. Estudos apontam que o genótipo do CFTR e a idade dos indivíduos influenciam as concentrações de cloreto no suor. Objetivos: pesquisar a correlação entre os níveis de cloreto no teste do suor e a idade ao diagnóstico de indivíduos com fibrose cística e comparar as concentrações iônicas do cloreto entre os sexos, diferentes faixas etárias e três grupos diversos de genótipos do CFTR. Metodologia: realizou-se um estudo de corte transversal, incluindo sujeitos de 0 a 20 anos, com diagnóstico confirmado de fibrose cística. Os indivíduos selecionados foram agrupados de acordo com as variáveis analisadas. Calcularam-se os valores descritivos das concentrações de íons cloreto de cada grupo. Utilizou-se o teste de Spearman para a análise da correlação entre a idade ao diagnóstico e os níveis de cloreto no suor. Resultados: 64 indivíduos foram incluídos no estudo, sendo 51,56% do sexo masculino. A mediana (Min ­ Max) da idade ao diagnóstico foi de 7 meses (1-206). Não foi observa da correlação entre a idade dos indivíduos ao diagnóstico e os níveis de cloreto no suor. As concentrações medianas de cloreto foram maiores nos escolares (106 mEq/l), no sexo feminino (102 mEq/l) e nos heterozigotos F508del/Classe I a III (108 mEq/l); e menores nos adolescentes (100 mEq/l) e nos heterozigotos F508del/Classes IV a VI (77 mEq/l). Conclusão: os níveis de cloreto no suor não apresentaram correlação com a idade dos indivíduos ao diagnóstico. A variação considerável dos níveis iônicos entre os grupos de diferentes genótipos corrobora que o teste do suor é um bom preditor da avaliação funcional do canal CFTR.

Introduction: cystic fibrosis is the most common autosomal recessive disorder in Caucasian populations and its etiology is associated with pathogenic variants in the CFTR gene. The sweat test is considered the gold standard for the diagnosis of the disease. Some studies suggest that CFTR genotype and age affect sweat chloride concentrations. Objectives: to investigate the correlation between sweat chloride levels and age at diagnosis of individuals with cystic fibrosis and to compare ionic chloride concentrations among sexes, different age groups and three distinct groups of CFTR genotypes. Methodology: a cross-sectional study was conducted, which included CF subjects from 0 to 20 years of age. The selected individuals were clustered on the variables in analysis. The description values for chloride ion concentrations in each group were calculated. The Spearman's test was used to analyze the correlation between the age at diagnosis and sweat chloride levels. Results: 64 individuals were included, 51,56% male. The median (Min ­ Max) age at diagnosis was 7 months (1-206). There was no correlation between the age at diagnosis and sweat chloride levels. The median of the chloride concentrations were higher for schoolchildren (106 mEq/l), females (102 mEq/l) and heterozygous F508del/Classes I to III (108 mEq/l), and reached the lowest values for teenagers (100 mEq/l) and heterozygous F508del/Classes IV to VI (77 mEq/l). Conclusion: sweat chloride levels did not correlate with the age of individuals at diagnosis. The substantial variation of ionic levels among groups of distinct genotypes corroborates that the sweat test is a good predictor for functional assessment of the CFTR channel.

Efficacy of Qingfei Huatantang in Treatment of COPD by Up-regulating Expression of CFTR Through JAK2/STAT3 Pathway / 中国实验方剂学杂志

Objective:To explore the efficacy and mechanism of Qingfei Huatan Tang on chronic obstructive pulmonary disease (COPD). Method:The rat model of COPD was established through smoke inhalation combined with lipopolysaccharide (LPS) and pulmonary compound injection. After successful modeling, the rats were randomly divided into 6 groups, namely the control group, the COPD model group, low, medium and high-dose Qingfei Huatan Tang groups and the ambroxol group. After 28 days of modeling, the drug was administered. Low, medium and high-dose Qingfei Huatan Tang (7.5, 15, 30 g·kg-1) and ambroxol (35 mg·kg-1) were administered continuously for 14 days. Immunohistochemistry and Real-time fluorescence quantitative polymerase chain reaction (Real-time PCR) were used to detect protein expression and mRNA expression of cystic fibrosis transmembrane conductance regulator (CFTR) in pulmonary fibrosis. NCI-H292 cells were induced by LPS to establish a mucus hypersecretion model. The experiment was divided into 8 groups, namely the blank control group, LPS group, LPS+10% fetal bovine serum group, LPS+ physiological serum group, LPS+5% drug serum group, LPS+10% drug serum group, LPS+20% drug serum group and LPS+AG490 group. Immunofluorescence, Western blot and Real-time PCR were used to observe the protein and mRNA expressions of CFTR in NCI-H292 cells after LPS stimulation, and western blot was used to detect the expression of tyrosine kinase 2/transcription factor 3 (JAK2/STAT3) signaling pathway in NCI-H292 cells after LPS stimulation. Result:There were a large number of brown particles around the lumen of lung tissues in the normal group, with increased COPD expression. There were a few brown particles around the lumen of lung tissues in the model group compared with the normal group, with decreased COPD expression. Compared with the normal group, mRNA and protein expressions of CFTR in the lung tissues of the COPD model group were significantly decreased (P<0.05). Compared with the model group, mRNA and protein expressions of CFTR in the lung tissues of low, medium and high-dose Qingfei Huatan Tang groups (P<0.05). Compared with the blank control group, mRNA and protein expressions of CFTR in NCI-H292 cells of the LPS group (P<0.05), with significant increases in protein expressions of p-JAK2 and p-STAT3 (P<0.05). Compared with the model group, 5%, 10%, 20% Qingfei Huatan Tang-containing serum groups showed significant increases in mRNA and protein expressions of CFTR, but with significant decreases in p-JAK2, p-STAT3 protein expressions (P<0.05, P<0.01). Conclusion:Qingfei Huatan Tang up-regulated CFTR in the treatment of COPD by inhibiting JAK2/STAT3 pathway.

Conditional reprogramming: next generation cell culture

Long-term primary culture of mammalian cells has been always difficult due to unavoidable senescence. Conventional methods for generating immortalized cell lines usually require manipulation of genome which leads to change of important biological and genetic characteristics. Recently, conditional reprogramming (CR) emerges as a novel next generation tool for long-term culture of primary epithelium cells derived from almost all origins without alteration of genetic background of primary cells. CR co-cultures primary cells with inactivated mouse 3T3-J2 fibroblasts in the presence of RHO-related protein kinase (ROCK) inhibitor Y-27632, enabling primary cells to acquire stem-like characteristics while retain their ability to fully differentiate. With only a few years' development, CR shows broad prospects in applications in varied areas including disease modeling, regenerative medicine, drug evaluation, drug discovery as well as precision medicine. This review is thus to comprehensively summarize and assess current progress in understanding mechanism of CR and its wide applications, highlighting the value of CR in both basic and translational researches and discussing the challenges faced with CR.

Chloride and sodium ion concentrations in saliva and sweat as a method to diagnose cystic fibrosis / Dosagem da concentração dos íons cloreto e sódio na saliva e no suor para o reconhecimento de pacientes com fibrose cística

Abstract Objective: Cystic fibrosis diagnosis is dependent on the chloride ion concentration in the sweat test (≥ 60 mEq/mL - recognized as the gold standard indicator for cystic fibrosis diagnosis). Moreover, the salivary glands express the CFTR protein in the same manner as sweat glands. Given this context, the objective was to verify the correlation of saliva chloride concentration and sweat chloride concentration, and between saliva sodium concentration and sweat sodium concentration, in patients with cystic fibrosis and healthy control subjects, as a tool for cystic fibrosis diagnosis. Methods: There were 160 subjects enrolled: 57/160 (35.70%) patients with cystic fibrosis and two known CFTR mutations and 103/160 (64.40%) healthy controls subjects. Saliva ion concentration was analyzed by ABL 835 Radiometer® equipment and, sweat chloride concentration and sweat sodium concentration, respectively, by manual titration using the mercurimetric procedure of Schales & Schales and flame photometry. Statistical analysis was performed by the chi-squared test, the Mann -Whitney test, and Spearman's correlation. Alpha = 0.05. Results: Patients with cystic fibrosis showed higher values of sweat chloride concentration, sweat sodium concentration, saliva chloride concentration, and saliva sodium concentration than healthy controls subjects (p-value < 0.001). The correlation between saliva chloride concentration and sweat chloride concentration showed a positive Spearman's Rho (correlation coefficient) = 0.475 (95% CI = 0.346 to 0.587). Also, the correlation between saliva sodium concentration and sweat sodium concentration showed a positive Spearman's Rho = 0.306 (95% CI = 0.158 to 0.440). Conclusions: Saliva chloride concentration and saliva sodium concentration are candidates to be used in cystic fibrosis diagnosis, mainly in cases where it is difficult to achieve the correct sweat amount, and/or CFTR mutation screening is difficult, and/or reference methods for sweat test are unavailable to implement or are not easily accessible by the general population.

Resumo Objetivo: O diagnóstico da fibrose cística depende do valor da concentração de íons de cloreto no teste do suor (≥ 60 mEq/mL - reconhecido como o indicador-padrão para o diagnóstico da doença). Além disso, as glândulas salivares expressam a proteína RTFC igualmente às glândulas sudoríparas. Nesse contexto, nosso objetivo foi verificar a correlação da concentração de cloreto na saliva e a concentração de cloreto no suor e entre a concentração de sódio na saliva e a concentração de sódio no suor em pacientes com fibrose cística e indivíduos controles saudáveis, como uma ferramenta para diagnóstico de fibrose cística. Métodos: Contamos com a participação de 160 indivíduos [57/160 (35,70%) com fibrose cística e duas mutações no gene RTFC conhecidas e 103/160 (64,40%) indivíduos controles saudáveis]. A concentração de íons na saliva foi analisada pelo equipamento ABL 835 da Radiometer® e a concentração de cloreto no suor e sódio no suor, respectivamente, por titulação manual utilizando o método mercurimétrico de Schales & Schales e fotometria de chama. A análise estatística foi realizada pelo teste qui-quadrado, pelo teste de Mann-Whitney e pela correlação de Spearman. Alpha = 0,05. Resultados: Os pacientes com fibrose cística apresentaram maiores valores na concentração de cloreto no suor, concentração de sódio no suor, concentração de cloreto na saliva e concentração de sódio na saliva do que os indivíduos-controle saudáveis (valor de p < 0,001). A correlação entre as concentrações de cloreto na saliva e cloreto no suor mostrou Rho de Spearman (coeficiente de correlação) positivo = 0,475 (IC de 95% = 0,346 a 0,587). Além disso, a correlação entre concentração de sódio na saliva e concentração de sódio no suor mostrou Rho de Spearman positivo = 0,306 (IC de 95% = 0,158 a 0,440). Conclusões: A concentração de cloreto na saliva e a concentração de sódio na saliva são candidatas a ser usadas como diagnóstico de fibrose cística, principalmente em casos em que é difícil atingir a quantidade correta de suor, e/ou o exame da mutação RTFC é difícil e/ou o método de referência para o teste do suor não se encontra disponível ou não é de fácil acesso ao público em geral.

Evaluation of respiratory dynamics by volumetric capnography during submaximal exercise protocol of six minutes on treadmill in cystic fibrosis patients / Avaliação da dinâmica respiratória por capnografia volumétrica durante o protocolo de exercício submáximo por seis minutos em esteira em pacientes com fibrose cística

Abstract Objectives: Volumetric capnography provides the standard CO2 elimination by the volume expired per respiratory cycle and is a measure to assess pulmonary involvement. Thus, the objective of this study was to evaluate the respiratory dynamics of healthy control subjects and those with cystic fibrosis in a submaximal exercise protocol for six minutes on the treadmill, using volumetric capnography parameters (slope 3 [Slp3], Slp3/tidal volume [Slp3/TV], and slope 2 [Slp2]). Methods: This was a cross-sectional study with 128 subjects (cystic fibrosis, 64 subjects; controls, 64 subjects]. Participants underwent volumetric capnography before, during, and after six minutes on the treadmill. Statistical analysis was performed using the Friedman, Mann-Whitney, and Kruskal-Wallis tests, considering age and sex. An alpha = 0.05 was considered. Results: Six minutes on the treadmill evaluation: in cystic fibrosis, volumetric capnography parameters were different before, during, and after six minutes on the treadmill; the same was observed for the controls, except for Slp2. Regarding age, an Slp3 difference was observed in cystic fibrosis patients regardless of age, at all moments, and in controls for age ≥ 12 years; a difference in Slp3/TV was observed in cystic fibrosis and controls, regardless of age; and an Slp2 difference in the cystic fibrosis, regardless of age. Regarding sex, Slp3 and Slp3/TV differences were observed in cystic fibrosis regardless of sex, and in controls in male participants; an Slp2 difference was observed in the cystic fibrosis and female participants. The analysis between groups (cystic fibrosis and controls) indicated that Slp3 and Slp3/TV has identified the CF, regardless of age and sex, while the Slp2 showed the CF considering age. Conclusions: Cystic fibrosis showed greater values of the parameters before, during, and after exercise, even when stratified by age and sex, which may indicate ventilation inhomogeneity in the peripheral pathways in the cystic fibrosis.

Resumo Objetivos: A capnografia volumétrica fornece o padrão de eliminação do CO2, pelo volume expirado por ciclo respiratório e avalia o comprometimento pulmonar. O objetivo do estudo foi avaliar a dinâmica respiratória de indivíduos controles saudáveis e em indivíduos com fibrose cística, em um protocolo de exercício submáximo por seis minutos em esteira, por parâmetros da capnografia volumétrica [slope 3(Slp3), Slp3/volume corrente (Slp3/TV) e slope 2(Slp2)]. Métodos: Estudo de corte transversal com 128 indivíduos [(fibrose cística) 64 indivíduos; (controles) 64 indivíduos]. Os participantes realizaram capnografia volumétrica antes, durante e após seis minutos em esteira. Análise estatística realizada pelos testes de Friedman, Mann-Whitney e Kruskal-Wallis, considerado a idade e o sexo. Alpha = 0,05. Resultados: Avaliação de seis minutos em esteira: na fibrose cística, os parâmetros da capnografia volumétrica foram diferentes antes, durante e após seis minutos em esteira, o mesmo ocorreu nos controles, exceto para o Slp2. Considerando a idade: (Slp3) diferença na FC, independentemente da idade, em todos os momentos e nos controles apenas para ≥ 12 anos; (Slp3/TV) diferença para fibrose cística e controles independentemente da idade; (Slp2) diferença apenas para o grupo fibrose cística, independentemente da idade. Considerando o sexo: (Slp3 e Slp3/TV) diferença para fibrose cística, independentemente do sexo, e controles apenas no sexo masculino; (Slp2) diferença para fibrose cística e sexo feminino. Análise entre grupos (fibrose cística versus controles): Slp3 e Slp3/TV identificou a fibrose cística, independentemente da idade e sexo, enquanto o Slp2 evidenciou a fibrose cística considerando a idade. Conclusão: A fibrose cística apresentou maiores valores dos parâmetros antes, durante e após exercício, inclusive quando se considerou idade e sexo, podendo indicar não homogeneidade da distribuição da ventilação nas vias periféricas.

Clinical characterization and diagnosis of cystic fibrosis through exome sequencing in Chinese infants with Bartter-syndrome-like hypokalemia alkalosis / 医学前沿

Cystic fibrosis (CF) is a fatal autosomal-recessive disease caused by mutations in the CF transmembrane conductance regulator (CFTR) gene. CF is characterized by recurrent pulmonary infection with obstructive pulmonary disease. CF is common in the Caucasian population but is rare in the Chinese population. The symptoms of early-stage CF are often untypical and may sometimes manifest as Bartter syndrome (BS)-like hypokalemic alkalosis. Therefore, the ability of doctors to differentiate CF from BS-like hypokalemic alkalosis in Chinese infants is a great challenge in the timely and accurate diagnosis of CF. In China, sporadic CF has not been diagnosed in children younger than three years of age to date. Three infants, who were initially admitted to our hospital over the period of June 2013 to September 2014 with BS-like hypokalemic alkalosis, were diagnosed with CF through exome sequencing and sweat chloride measurement. The compound heterozygous mutations of the CFTR gene were detected in two infants, and a homozygous missense mutation was found in one infant. Among the six identified mutations, two are novel point mutations (c.1526G > C and c.3062C > T) that are possibly pathogenic. The three infants are the youngest Chinese patients to have been diagnosed with sporadic CF at a very early stage. Follow-up examination showed that all of the cases remained symptom-free after early intervention, indicating the potential benefit of very early diagnosis and timely intervention in children with CF. Our results demonstrate the necessity of distinguishing CF from BS in Chinese infants with hypokalemic alkalosis and the significant diagnostic value of powerful exome sequencing for rare genetic diseases. Furthermore, our findings expand the CFTR mutation spectrum associated with CF.

Variants in the interleukin 8 gene and the response to inhaled bronchodilators in cystic fibrosis / Variantes no gene da interleucina 8 e a resposta a broncodilatadores inalatórios na fibrose cística

Abstract Objective: Interleukin 8 protein promotes inflammatory responses, even in airways. The presence of interleukin 8 gene variants causes altered inflammatory responses and possibly varied responses to inhaled bronchodilators. Thus, this study analyzed the interleukin 8 variants (rs4073, rs2227306, and rs2227307) and their association with the response to inhaled bronchodilators in cystic fibrosis patients. Methods: Analysis of interleukin 8 gene variants was performed by restriction fragment length polymorphism of polymerase chain reaction. The association between spirometry markers and the response to inhaled bronchodilators was evaluated by Mann-Whitney and Kruskal-Wallis tests. The analysis included all cystic fibrosis patients, and subsequently patients with two mutations in the cystic fibrosis transmembrane conductance regulator gene belonging to classes I to III. Results: This study included 186 cystic fibrosis patients. There was no association of the rs2227307 variant with the response to inhaled bronchodilators. The rs2227306 variant was associated with FEF50% in the dominant group and in the group with two identified mutations in the cystic fibrosis transmembrane conductance regulator gene. The rs4073 variant was associated with spirometry markers in four genetic models: co-dominant (FEF25-75% and FEF75%), dominant (FEV1, FEF50%, FEF75%, and FEF25-75%), recessive (FEF75% and FEF25-75%), and over-dominant (FEV1/FVC). Conclusions: This study highlighted the importance of the rs4073 variant of the interleukin 8 gene, regarding response to inhaled bronchodilators, and of the assessment of mutations in the cystic fibrosis transmembrane conductance regulator gene.

Resumo Objetivo: A proteína interleucina 8 promove respostas inflamatórias, o que inclui sua atuação nas vias aéreas. A presença de variantes no gene da interleucina 8 causa respostas inflamatórias alteradas e possivelmente respostas variadas ao uso de broncodilatadores inalatórios. Assim, este estudo analisou as variantes da interleucina 8 (rs4073, rs2227306, rs2227307) e sua associação à resposta a broncodilatadores inalatórios em pacientes com fibrose cística. Métodos: Foi feita análise das variantes genéticas da interleucina 8 por restriction fragment length polymorphism da reação em cadeia da polimerase. A associação entre os marcadores da espirometria e a resposta a broncodilatadores inalatórios foi feita pelos testes de Mann-Whitney e Kruskal-Wallis. A análise incluiu todos os pacientes com fibrose cística e posteriormente pacientes com duas mutações no gene cystic fibrosis transmembrane conductance regulator pertencentes às Classes I a II. Resultados: Este estudo incluiu 186 pacientes com fibrose cística. Não houve associação da variante rs2227307 à resposta a broncodilatadores inalatórios. A variante rs2227306 foi associada a FEF50% no grupo dominante e no grupo com duas mutações identificadas no gene cystic fibrosis transmembrane conductance regulator. A variante rs4073 foi associada a marcadores da espirometria em quatro modelos genéticos: codominante (FEF25-75% e FEF75%), dominante (VEF1, FEF50%, FEF75% e FEF25-75%), recessivo (FEF75% e FEF25-75%) e overdominante (VEF1/CVF). Conclusões: Este estudo destaca, principalmente, a importância da variante rs4073 do gene da interleucina 8, na resposta a broncodilatadores inalatórios, concomitantemente ao genótipo das mutações no gene cystic fibrosis transmembrane conductance regulator.

CFTR in Cardiovascular Functions / 中山大学学报(医学科学版)

Cystic fibrosis transmembrane conductance regulator(CFTR)is an ATP-gated,cAMP-dependent chloride channel. The basic biophysical and pathological functions of CFTR are related with the secretion of chloride ion in epithelial cells and tissues. Mutations in CFTR cause cystic fibrosis(CF),which is a rare but fatal autosomal recessive inheritant disease ,mainly affecting glan?dular epithelial function in respiratory tract ,intestinal and reproductive system. New drugs targeting human CFTR gene mutations have been developed to significantly prolong lifeand improve respiratory symptoms of CF patients. Recent evidence suggested that CFTR plays a functional role in vasoconstriction and the formation of myocardial action potential. As a channel protein ,CFTR may al?so functions as a multiprotein/channel complex ,which has been demonstrated in the development of cardiovascular diseases such as myocardial ischemia and pulmonary hypertension.

Newborn Screening Quality Assurance Program for CFTR Mutation Detection and Gene Sequencing to Identify Cystic Fibrosis

Abstract All newborn screening laboratories in the United States and many worldwide screen for cystic fibrosis. Most laboratories use a second-tier genotyping assay to identify a panel of mutations in the CF transmembrane regulator (CFTR) gene. Centers for Disease Control and Prevention's Newborn Screening Quality Assurance Program houses a dried blood spot repository of samples containing CFTR mutations to assist newborn screening laboratories and ensure high-quality mutation detection in a high-throughput environment. Recently, CFTR mutation detection has increased in complexity with expanded genotyping panels and gene sequencing. To accommodate the growing quality assurance needs, the repository samples were characterized with several multiplex genotyping methods, Sanger sequencing, and 3 next-generation sequencing assays using a high-throughput, low-concentration DNA extraction method. The samples performed well in all of the assays, providing newborn screening laboratories with a resource for complex CFTR mutation detection and next-generation sequencing as they transition to new methods.

PRSS1, SPINK1, CFTR, and CTRC Pathogenic Variants in Korean Patients With Idiopathic Pancreatitis

BACKGROUND: This study aimed to identify pathogenic variants of PRSS1, SPINK1, CFTR, and CTRC genes in Korean patients with idiopathic pancreatitis. METHODS: The study population consisted of 116 Korean subjects (65 males, 51 females; mean age, 30.4 yr, range, 1-88 yr) diagnosed with idiopathic chronic pancreatitis (ICP), idiopathic recurrent acute pancreatitis (IRAP), or idiopathic acute pancreatitis (IAP). We analyzed sequences of targeted regions in the PRSS1, SPINK1, CFTR, and CTRC genes, copy numbers of PRSS1 and SPINK1, and clinical data from medical records. RESULTS: We identified three types of pathogenic PRSS1 variants in 11 patients, including p.N29I (n=1), p.R122H (n=1), and p.G208A (n=9). Sixteen patients exhibited heterozygous pathogenic variants of SPINK1, including c.194+2T>C (n=12), p.N34S (n=3), and a novel pathogenic splicing variation c.194+1G>A. A heterozygous CFTR p.Q1352H pathogenic variant was detected in eight patients. One patient carried a heterozygous CTRC p.P249L pathogenic variant, which is a known high-risk variant for pancreatitis. All patients had normal PRSS1 and SPINK1 gene copy numbers. Weight loss occurred more frequently in patients carrying the p.G208A pathogenic variant, while pancreatic duct stones occurred more frequently in patients with the c.194+2T>C pathogenic variant. CONCLUSIONS: Pathogenic variants of PRSS1, SPINK1, and CFTR were associated with idiopathic pancreatitis, while pathogenic variants of CTRC were not. Copy number variations of PRSS1 and SPINK1 were not detected.

Application Progress in CFTR Inhibitors in the Treatment of Secretory Diarrhea / 中国药师

Secretory diarrhea provides a major health challenge worldwide, which is one of the most important reasons for children morbidity and death. The activation of Cl- channels in intestinal epithelial cells resulting in the excessive fluid secretion in the intestine is the main reason of diarrhea caused by enterotoxins. In diarrhea caused by cholera and the other bacterial enterotoxins, cystic fibrosis transmembrane conductance regulator ( CFTR) is the main cAMP-control Cl- channel to promote the fluid secretion in epithelial cells. Therefore, CFTR inhibitors are the new choices for secretory diarrhea. CFTR inhibitors include thiazolidinone, glycine hydrazide and quinoxalinedione chemical classes, and some components from natural plants also exhibit CFTR inhibition activity, however, further studies should be done.

Current developments in pharmacological therapeutics for chronic constipation

Chronic constipation is a common gastrointestinal disease severely affecting the patient׳s quality of life. The traditional treatment of constipation is the use of laxatives. Recently, several new drugs including lubiprostone, linaclotide and prucalopride have been approved for treatment of chronic constipation. However, a significant unmet medical need still remains, particularly among those patients achieving poor results by current therapies. The 5-HT4 receptor modulators velusetrag and naronapride, the guanylate cyclase C agonist plecanatide and the ileal bile acid transporter inhibitor elobixibat are recognized as the most promising drugs under investigation. Herein, we give a comprehensive review on the pharmacological therapeutics for the treatment of chronic constipation, with the purpose of reflecting the drug development trends in this field.