Cystic Fibrosis

The Relationship between Body Composition, Dietary Intake, Physical Activity, and Pulmonary Status in Adolescents and Adults with Cystic Fibrosis

Fri, 2022-01-21 06:00

Nutrients. 2022 Jan 12;14(2):310. doi: 10.3390/nu14020310.

ABSTRACT

Measures of body fat and lean mass may better predict important clinical outcomes in patients with cystic fibrosis (CF) than body mass index (BMI). Little is known about how diet quality and exercise may impact body composition in these patients. Dual X-ray absorptiometry (DXA) body composition, 24-h dietary recall, and physical activity were assessed in a cross-sectional analysis of 38 adolescents and adults with CF and 19 age-, race-, and gender-matched healthy volunteers. Compared with the healthy volunteers, participants with CF had a lower appendicular lean mass index (ALMI), despite no observed difference in BMI, and their diets consisted of higher glycemic index foods with a greater proportion of calories from fat and a lower proportion of calories from protein. In participants with CF, pulmonary function positively correlated with measures of lean mass, particularly ALMI, and negatively correlated with multiple measures of body fat after controlling for age, gender, and BMI. Higher physical activity levels were associated with greater ALMI and lower body fat. In conclusion, body composition measures, particularly ALMI, may better predict key clinical outcomes in individuals with CF than BMI. Future longitudinal studies analyzing the effect of dietary intake and exercise on body composition and CF-specific clinical outcomes are needed.

PMID:35057491 | DOI:10.3390/nu14020310

Categories: Literature Watch

Evaluation of the Mucoadhesive Properties of Chitosan-Based Microstructured Lipid Carrier (CH-MLC)

Fri, 2022-01-21 06:00

Pharmaceutics. 2022 Jan 12;14(1):170. doi: 10.3390/pharmaceutics14010170.

ABSTRACT

Different mucoadhesive systems have been studied in recent years to increase the residence time of the delivery systems and to prolong the release of the drug. The aim of this work was to evaluate the mucoadhesive properties of chitosan-based Microstructured Lipid Carrier (CH-MLC) with a new approach which requires chitosan and mucin to be compacted into a tablet and mucoadhesion to be assessed on a non-mucoadhesive substrate. This type of test showed that chitosan maintains a close bond with mucin even in the presence of a fluid and even encapsulated in microparticles. After this, using a bioreactor, the release of N-acetylcysteine (NAC) from the microparticles (NA-CH-MLC) through a layer of mucus mimicking the pathological conditions of a patient with cystic fibrosis was tested. The release of the active from NAC-CH-MLC demonstrated how the chitosan inside the microparticles acts as a penetration enhancer and how the microparticles can impart a prolonged release over time.

PMID:35057065 | DOI:10.3390/pharmaceutics14010170

Categories: Literature Watch

Aerosol-Mediated Non-Viral Lung Gene Therapy: The Potential of Aminoglycoside-Based Cationic Liposomes

Fri, 2022-01-21 06:00

Pharmaceutics. 2021 Dec 23;14(1):25. doi: 10.3390/pharmaceutics14010025.

ABSTRACT

Aerosol lung gene therapy using non-viral delivery systems represents a credible therapeutic strategy for chronic respiratory diseases, such as cystic fibrosis (CF). Progress in CF clinical setting using the lipidic formulation GL67A has demonstrated the relevance of such a strategy while emphasizing the need for more potent gene transfer agents. In recent years, many novel non-viral gene delivery vehicles were proposed as potential alternatives to GL67 cationic lipid. However, they were usually evaluated using procedures difficult or even impossible to implement in clinical practice. In this study, a clinically-relevant administration protocol via aerosol in murine lungs was used to conduct a comparative study with GL67A. Diverse lipidic compounds were used to prepare a series of formulations inspired by the composition of GL67A. While some of these formulations were ineffective at transfecting murine lungs, others demonstrated modest-to-very-efficient activities and a series of structure-activity relationships were unveiled. Lipidic aminoglycoside derivative-based formulations were found to be at least as efficient as GL67A following aerosol delivery of a luciferase-encoding plasmid DNA. A single aerosol treatment with one such formulation was found to mediate long-term lung transgene expression, exceeding half the animal's lifetime. This study clearly supports the potential of aminoglycoside-based cationic lipids as potent GL67-alternative scaffolds for further enhanced aerosol non-viral lung gene therapy for diseases such as CF.

PMID:35056921 | DOI:10.3390/pharmaceutics14010025

Categories: Literature Watch

The Use of Targeted Monoclonal Antibodies in the Treatment of ABPA-A Case Series

Fri, 2022-01-21 06:00

Medicina (Kaunas). 2021 Dec 29;58(1):53. doi: 10.3390/medicina58010053.

ABSTRACT

Allergic bronchopulmonary aspergillosis (ABPA) is a pulmonary disorder occurring in response to Aspergillus fumigatus that can complicate the course of asthma and cystic fibrosis. Here we present a case of acute ABPA without central bronchiectasis, a case of chronic active ABPA with central bronchiectasis, and a case of severe relapsing ABPA with central bronchiectasis. All three were initially treated with corticosteroids and antifungal agents but had an incomplete response. These patients were then treated with anti-IgE therapy with omalizumab before being switched to the anti-IL5R agent benralizumab. They responded well to both agents. These case reports highlight the potential role of omalizumab and benralizumab in the treatment of ABPA, but further studies are required to evaluate the effectiveness of these medications. Longer follow-up periods and objective measurements of the impact of treatment are necessary.

PMID:35056359 | DOI:10.3390/medicina58010053

Categories: Literature Watch

Ultraviolet-C Irradiation, Heat, and Storage as Potential Methods of Inactivating SARS-CoV-2 and Bacterial Pathogens on Filtering Facepiece Respirators

Fri, 2022-01-21 06:00

Pathogens. 2022 Jan 10;11(1):83. doi: 10.3390/pathogens11010083.

ABSTRACT

The arrival of SARS-CoV-2 to Aotearoa/New Zealand in February 2020 triggered a massive response at multiple levels. Procurement and sustainability of medical supplies to hospitals and clinics during the then upcoming COVID-19 pandemic was one of the top priorities. Continuing access to new personal protective equipment (PPE) was not guaranteed; thus, disinfecting and reusing PPE was considered as a potential alternative. Here, we describe part of a local program intended to test and implement a system to disinfect PPE for potential reuse in New Zealand. We used filtering facepiece respirator (FFR) coupons inoculated with SARS-CoV-2 or clinically relevant multidrug-resistant pathogens (Acinetobacter baumannii Ab5075, methicillin-resistant Staphylococcus aureus USA300 LAC and cystic-fibrosis isolate Pseudomonas aeruginosa LESB58), to evaluate the potential use of ultraviolet-C germicidal irradiation (UV-C) or dry heat treatment to disinfect PPE. An applied UV-C dose of 1000 mJ/cm2 was sufficient to completely inactivate high doses of SARS-CoV-2; however, irregularities in the FFR coupons hindered the efficacy of UV-C to fully inactivate the virus, even at higher UV-C doses (2000 mJ/cm2). Conversely, incubating contaminated FFR coupons at 65 °C for 30 min or 70 °C for 15 min, was sufficient to block SARS-CoV-2 replication, even in the presence of mucin or a soil load (mimicking salivary or respiratory secretions, respectively). Dry heat (90 min at 75 °C to 80 °C) effectively killed 106 planktonic bacteria; however, even extending the incubation time up to two hours at 80 °C did not completely kill bacteria when grown in colony biofilms. Importantly, we also showed that FFR material can harbor replication-competent SARS-CoV-2 for up to 35 days at room temperature in the presence of a soil load. We are currently using these findings to optimize and establish a robust process for decontaminating, reusing, and reducing wastage of PPE in New Zealand.

PMID:35056031 | DOI:10.3390/pathogens11010083

Categories: Literature Watch

Lung Microbiome in Idiopathic Pulmonary Fibrosis and Other Interstitial Lung Diseases

Fri, 2022-01-21 06:00

Int J Mol Sci. 2022 Jan 17;23(2):977. doi: 10.3390/ijms23020977.

ABSTRACT

Interstitial lung diseases represent a heterogeneous and wide group of diseases in which factors leading to disease initiation and progression are not fully understood. Recent evidence suggests that the lung microbiome might influence the pathogenesis and progression of interstitial lung diseases. In recent years, the utilization of culture-independent methodologies has allowed the identification of complex and dynamic communities of microbes, in patients with interstitial lung diseases. However, the potential mechanisms by which these changes may drive disease pathogenesis and progression are largely unknown. The aim of this review is to discuss the role of the altered lung microbiome in several interstitial lung diseases. Untangling the host-microbiome interaction in the lung and airway of interstitial lung disease patients is a research priority. Thus, lung dysbiosis is a potentially treatable trait across several interstitial lung diseases, and its proper characterization and treatment might be crucial to change the natural history of these diseases and improve outcomes.

PMID:35055163 | DOI:10.3390/ijms23020977

Categories: Literature Watch

Antibodies against Angiotensin II Type 1 and Endothelin 1 Type A Receptors in Cardiovascular Pathologies

Fri, 2022-01-21 06:00

Int J Mol Sci. 2022 Jan 15;23(2):927. doi: 10.3390/ijms23020927.

ABSTRACT

Angiotensin II receptor type 1 (AT1R) and endothelin-1 receptor type A (ETAR) are G-protein-coupled receptors (GPCRs) expressed on the surface of a great variety of cells: immune cells, vascular smooth cells, endothelial cells, and fibroblasts express ETAR and AT1R, which are activated by endothelin 1 (ET1) and angiotensin II (AngII), respectively. Certain autoantibodies are specific for these receptors and can regulate their function, thus being known as functional autoantibodies. The function of these antibodies is similar to that of natural ligands, and it involves not only vasoconstriction, but also the secretion of proinflammatory cytokines (such as interleukin-6 (IL6), IL8 and TNF-α), collagen production by fibroblasts, and reactive oxygen species (ROS) release by fibroblasts and neutrophils. The role of autoantibodies against AT1R and ETAR (AT1R-AAs and ETAR-AAs, respectively) is well described in the pathogenesis of many medical conditions (e.g., systemic sclerosis (SSc) and SSc-associated pulmonary hypertension, cystic fibrosis, and allograft dysfunction), but their implications in cardiovascular diseases are still unclear. This review summarizes the current evidence regarding the effects of AT1R-AAs and ETAR-AAs in cardiovascular pathologies, highlighting their roles in heart transplantation and mechanical circulatory support, preeclampsia, and acute coronary syndromes.

PMID:35055116 | DOI:10.3390/ijms23020927

Categories: Literature Watch

Therapeutic CFTR Correction Normalizes Systemic and Lung-Specific S1P Level Alterations Associated with Heart Failure

Fri, 2022-01-21 06:00

Int J Mol Sci. 2022 Jan 14;23(2):866. doi: 10.3390/ijms23020866.

ABSTRACT

Heart failure (HF) is among the main causes of death worldwide. Alterations of sphingosine-1-phosphate (S1P) signaling have been linked to HF as well as to target organ damage that is often associated with HF. S1P's availability is controlled by the cystic fibrosis transmembrane regulator (CFTR), which acts as a critical bottleneck for intracellular S1P degradation. HF induces CFTR downregulation in cells, tissues and organs, including the lung. Whether CFTR alterations during HF also affect systemic and tissue-specific S1P concentrations has not been investigated. Here, we set out to study the relationship between S1P and CFTR expression in the HF lung. Mice with HF, induced by myocardial infarction, were treated with the CFTR corrector compound C18 starting ten weeks post-myocardial infarction for two consecutive weeks. CFTR expression, S1P concentrations, and immune cell frequencies were determined in vehicle- and C18-treated HF mice and sham controls using Western blotting, flow cytometry, mass spectrometry, and qPCR. HF led to decreased pulmonary CFTR expression, which was accompanied by elevated S1P concentrations and a pro-inflammatory state in the lungs. Systemically, HF associated with higher S1P plasma levels compared to sham-operated controls and presented with higher S1P receptor 1-positive immune cells in the spleen. CFTR correction with C18 attenuated the HF-associated alterations in pulmonary CFTR expression and, hence, led to lower pulmonary S1P levels, which was accompanied by reduced lung inflammation. Collectively, these data suggest an important role for the CFTR-S1P axis in HF-mediated systemic and pulmonary inflammation.

PMID:35055052 | DOI:10.3390/ijms23020866

Categories: Literature Watch

Air-Liquid-Interface Differentiated Human Nose Epithelium: A Robust Primary Tissue Culture Model of SARS-CoV-2 Infection

Fri, 2022-01-21 06:00

Int J Mol Sci. 2022 Jan 13;23(2):835. doi: 10.3390/ijms23020835.

ABSTRACT

The global urgency to uncover medical countermeasures to combat the COVID-19 pandemic caused by the severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) has revealed an unmet need for robust tissue culture models that faithfully recapitulate key features of human tissues and disease. Infection of the nose is considered the dominant initial site for SARS-CoV-2 infection and models that replicate this entry portal offer the greatest potential for examining and demonstrating the effectiveness of countermeasures designed to prevent or manage this highly communicable disease. Here, we test an air-liquid-interface (ALI) differentiated human nasal epithelium (HNE) culture system as a model of authentic SARS-CoV-2 infection. Progenitor cells (basal cells) were isolated from nasal turbinate brushings, expanded under conditionally reprogrammed cell (CRC) culture conditions and differentiated at ALI. Differentiated cells were inoculated with different SARS-CoV-2 clinical isolates. Infectious virus release into apical washes was determined by TCID50, while infected cells were visualized by immunofluorescence and confocal microscopy. We demonstrate robust, reproducible SARS-CoV-2 infection of ALI-HNE established from different donors. Viral entry and release occurred from the apical surface, and infection was primarily observed in ciliated cells. In contrast to the ancestral clinical isolate, the Delta variant caused considerable cell damage. Successful establishment of ALI-HNE is donor dependent. ALI-HNE recapitulate key features of human SARS-CoV-2 infection of the nose and can serve as a pre-clinical model without the need for invasive collection of human respiratory tissue samples.

PMID:35055020 | DOI:10.3390/ijms23020835

Categories: Literature Watch

Polyphosphate Kinase 2 (PPK2) Enzymes: Structure, Function, and Roles in Bacterial Physiology and Virulence

Fri, 2022-01-21 06:00

Int J Mol Sci. 2022 Jan 8;23(2):670. doi: 10.3390/ijms23020670.

ABSTRACT

Inorganic polyphosphate (polyP) has been implicated in an astonishing array of biological functions, ranging from phosphorus storage to molecular chaperone activity to bacterial virulence. In bacteria, polyP is synthesized by polyphosphate kinase (PPK) enzymes, which are broadly subdivided into two families: PPK1 and PPK2. While both enzyme families are capable of catalyzing polyP synthesis, PPK1s preferentially synthesize polyP from nucleoside triphosphates, and PPK2s preferentially consume polyP to phosphorylate nucleoside mono- or diphosphates. Importantly, many pathogenic bacteria such as Pseudomonas aeruginosa and Acinetobacter baumannii encode at least one of each PPK1 and PPK2, suggesting these enzymes may be attractive targets for antibacterial drugs. Although the majority of bacterial polyP studies to date have focused on PPK1s, PPK2 enzymes have also begun to emerge as important regulators of bacterial physiology and downstream virulence. In this review, we specifically examine the contributions of PPK2s to bacterial polyP homeostasis. Beginning with a survey of the structures and functions of biochemically characterized PPK2s, we summarize the roles of PPK2s in the bacterial cell, with a particular emphasis on virulence phenotypes. Furthermore, we outline recent progress on developing drugs that inhibit PPK2 enzymes and discuss this strategy as a novel means of combatting bacterial infections.

PMID:35054854 | DOI:10.3390/ijms23020670

Categories: Literature Watch

First Case of COVID-19 Treated with Monoclonal Anti-Spike Antibodies in a Patient with Cystic Fibrosis in Romania

Fri, 2022-01-21 06:00

Diagnostics (Basel). 2022 Jan 7;12(1):137. doi: 10.3390/diagnostics12010137.

ABSTRACT

Patients with chronic lung conditions, including cystic fibrosis, may be prone to severe COVID-19. Therefore, therapeutic intervention should be prompt and tailored to all associated comorbidities. We report the case of a 17-year-old male adolescent with cystic fibrosis and multiple chronic conditions (bronchiectasis, exocrine pancreatic insufficiency, chronic multidrug resistant Pseudomonas aeruginosa colonization, nasal polyposis, chronic sinusitis, ventricular extrasystoles and multiple drug allergies), who presented with an acute episode of productive cough, and was confirmed with moderate COVID-19 based on positive RT-PCR for SARS-CoV-2 and lung imaging showing isolated foci of interstitial pneumonia. Intravenous treatment with the monoclonal antibody cocktail casirivimab and imdevimab was administered. The evolution was favorable, with rapid remission of the inflammatory syndrome and gradual decrease of cough, without progression to severe or critical COVID-19, but with complications such as repeated hemoptysis, which was due to the patient's underlying conditions, and which required close monitoring for timely adjustment of the patient's chronic treatment.

PMID:35054306 | DOI:10.3390/diagnostics12010137

Categories: Literature Watch

Correction: Dagenais et al. Real-World Safety of CFTR Modulators in the Treatment of Cystic Fibrosis: A Systematic Review. J. Clin. Med. 2021, 10, 23

Fri, 2022-01-21 06:00

J Clin Med. 2022 Jan 10;11(2):318. doi: 10.3390/jcm11020318.

ABSTRACT

In the original article [...].

PMID:35054167 | DOI:10.3390/jcm11020318

Categories: Literature Watch

Fat-Soluble Vitamins in Standard vs. Liposomal Form Enriched with Vitamin K2 in Cystic Fibrosis: A Randomized Multi-Center Trial

Fri, 2022-01-21 06:00

J Clin Med. 2022 Jan 17;11(2):462. doi: 10.3390/jcm11020462.

ABSTRACT

BACKGROUND: We aimed to assess a liposomal fat-soluble vitamin formulation containing vitamin K2 with standard treatment in cystic fibrosis (CF).

METHODS: A multi-center randomized controlled trial was carried out in 100 pancreatic-insufficient patients with CF. The liposomal formulation contained vitamin A as retinyl palmitate (2667 IU daily) and beta-carotene (1333 IU), D3 (4000 IU), E (150 IU), K1 (2 mg), and K2 as menaquinone-7 (400 µg). It was compared with the standard vitamin preparations in the closest possible doses (2500 IU, 1428 IU, 4000 IU, 150 IU, 2.14 mg, respectively; no vitamin K2) over 3 months.

RESULTS: Forty-two patients finished the trial in the liposomal and 49 in the control group (overall 91 pts: 22.6 ± 7.6 years, 62.6% female, BMI 19.9 ± 2.8 kg/m2, FEV1% 70% ± 30%). The main outcome was the change of vitamin status in the serum during the study (liposomal vs. standard): all-trans-retinol (+1.48 ± 95.9 vs. -43.1 ± 121.4 ng/mL, p = 0.054), 25-hydroxyvitamin D3 (+9.7 ± 13.4 vs. +2.0 ± 9.8 ng/mL, p = 0.004), α-tocopherol (+1.5 ± 2.5 vs. -0.2 ± 1.6 µg/mL, p < 0.001), %undercarboxylated osteocalcin (-17.2 ± 24.8% vs. -8.3 ± 18.5%, p = 0.061). The secondary outcome was the vitamin status at the trial end: all-trans-retinol (370.0 ± 116.5 vs. 323.1 ± 100.6 ng/mL, p = 0.045), 25-hydroxyvitamin D3 (43.2 ± 16.6 vs. 32.7 ± 11.5 ng/mL, p < 0.001), α-tocopherol (9.0 ± 3.1 vs. 7.7 ± 3.0 µg/mL, p = 0.037), %undercarboxylated osteocalcin (13.0 ± 11.2% vs. 22.7 ± 22.0%, p = 0.008).

CONCLUSION: The liposomal fat-soluble vitamin supplement containing vitamin K2 was superior to the standard form in delivering vitamin D3 and E in pancreatic-insufficient patients with CF. The supplement was also more effective in strengthening vitamin K-dependent carboxylation, and could improve vitamin A status.

PMID:35054157 | DOI:10.3390/jcm11020462

Categories: Literature Watch

The Impact of Vitamin K2 (Menaquionones) in Children's Health and Diseases: A Review of the Literature

Fri, 2022-01-21 06:00

Children (Basel). 2022 Jan 5;9(1):78. doi: 10.3390/children9010078.

ABSTRACT

Vitamin K2 activates vitamin K-dependent proteins that support many biological functions, such as bone mineralization, the inhibition of vascular stiffness, the improvement of endothelial function, the maintenance of strong teeth, brain development, joint health, and optimal body weight. Due to the transformation of food habits in developed countries over the last five decades, vitamin K and, specifically, vitamin K2 intakes among parents and their offspring have decreased significantly, resulting in serious health implications. The therapeutics used in pediatric practice (antibiotics and glucocorticoids) are also to blame for this situation. Low vitamin K status is much more frequent in newborns, due to both endogenous and exogenous insufficiencies. Just after birth vitamin K stores are low, and since human milk is relatively poor in this nutrient, breast-fed infants are at particular risk of a bleeding disorder called vitamin K deficiency bleeding. A pilot study showed that better vitamin K status is associated with lower rate of low-energy fracture incidence. An ongoing clinical trial is intended to address whether vitamin K2 and D3 supplementation might positively impact the biological process of bone healing. Vitamin K2 as menaquinone-7 (MK-7) has a documented history of safe and effective use. The lack of adverse effects of MK-7 makes it the ideal choice for supplementation by pregnant and nursing women and children, both healthy and suffering from various malabsorptions and health disorders, such as dyslipidemia, diabetes, thalassemia major (TM), cystic fibrosis (CF), inflammatory bowel diseases (IBD), and chronic liver diseases. Additionally, worthy of consideration is the use of vitamin K2 in obesity-related health outcomes.

PMID:35053702 | DOI:10.3390/children9010078

Categories: Literature Watch

Endolysosomal Cation Channels and Lung Disease

Fri, 2022-01-21 06:00

Cells. 2022 Jan 17;11(2):304. doi: 10.3390/cells11020304.

ABSTRACT

Endolysosomal cation channels are emerging as key players of endolysosomal function such as endolysosomal trafficking, fusion/fission, lysosomal pH regulation, autophagy, lysosomal exocytosis, and endocytosis. Diseases comprise lysosomal storage disorders (LSDs) and neurodegenerative diseases, metabolic diseases, pigmentation defects, cancer, immune disorders, autophagy related diseases, infectious diseases and many more. Involvement in lung diseases has not been a focus of attention so far but recent developments in the field suggest critical functions in lung physiology and pathophysiology. Thus, loss of TRPML3 was discovered to exacerbate emphysema formation and cigarette smoke induced COPD due to dysregulated matrix metalloproteinase 12 (MMP-12) levels in the extracellular matrix of the lung, a known risk factor for emphysema/COPD. While direct lung function measurements with the exception of TRPML3 are missing for other endolysosomal cation channels or channels expressed in lysosome related organelles (LRO) in the lung, links between those channels and important roles in lung physiology have been established such as the role of P2X4 in surfactant release from alveolar epithelial Type II cells. Other channels with demonstrated functions and disease relevance in the lung such as TRPM2, TRPV2, or TRPA1 may mediate their effects due to plasma membrane expression but evidence accumulates that these channels might also be expressed in endolysosomes, suggesting additional and/or dual roles of these channels in cell and intracellular membranes. We will discuss here the current knowledge on cation channels residing in endolysosomes or LROs with respect to their emerging roles in lung disease.

PMID:35053420 | DOI:10.3390/cells11020304

Categories: Literature Watch

National multi-centre study found a low prevalence of severely impaired lung function in children and adolescents

Thu, 2022-01-20 06:00

Acta Paediatr. 2022 Jan 20. doi: 10.1111/apa.16262. Online ahead of print.

ABSTRACT

AIM: As no data to our knowledge exists, the aim of the study was to describe the national prevalence and characteristics of Danish children and adolescents with severely impaired lung function.

METHODS: We performed a descriptive, cross-sectional Danish multi-centre study. Children and adolescents between 6-18 years old demonstrating severely impaired lung function from 2015-2018, defined by forced expiratory volume in 1 second (FEV1 ) <60% or who had lung transplantation were eligible for inclusion.

RESULTS: This study included 113 children with a mean age (standard deviation) of 12.9 years (3.5 years). The prevalence of severely impaired lung function was approximately 13 in 100,000. The mean (standard deviation) FEV1 was 46.1% (10.1%) of predicted and z-score was -4.5 (0.8). The most frequent diagnosis was cystic fibrosis (20.4%), followed by asthma (19.5%) and bronchiolitis obliterans (16.8%), while almost 25% had different elements of airway malformations or non-pulmonary conditions. Two adolescents with cystic fibrosis underwent lung transplantation.

CONCLUSION: The estimated prevalence of severely impaired lung function in Danish children and adolescents was low and extremely few children underwent lung transplantation. The most frequent diagnosis was cystic fibrosis, while almost 25% had different elements of airway malformations or non-pulmonary conditions, which may require clinical attention.

PMID:35051297 | DOI:10.1111/apa.16262

Categories: Literature Watch

Review article: epidemiology, pathogenesis and management of liver disease in adults with cystic fibrosis

Thu, 2022-01-20 06:00

Aliment Pharmacol Ther. 2022 Jan 19. doi: 10.1111/apt.16749. Online ahead of print.

ABSTRACT

BACKGROUND: Cystic fibrosis-related liver disease (CFLD) is the leading cause of death in cystic fibrosis (CF), after pulmonary disease. To improve identification and management of this condition requires an understanding of the underlying disease mechanism.

AIMS: This review summarises the current understanding of CFLD epidemiology, pathology, diagnosis and management.

METHODS: Relevant reports on cystic fibrosis liver disease were identified using a literature search and summarised.

RESULTS: CFLD is a heterogeneous condition with several different co-existent pathologies, including environmental and genetic factors. Incidence of clinically significant CFLD continues at a linear rate into early adulthood and has been described in up to 25% of CF patients. Diagnosis strategies lack precision and patient risk stratification needs to look beyond Childs-Pugh scoring. Efficacious therapies are lacking and, at present, newer modulator therapies lack data in CFLD and carry an increased risk of hepatotoxicity. Outcomes of liver transplant are comparable to non-CF transplant indications.

CONCLUSIONS: The incidence of CFLD increases with age and hence is increasingly important to adult patients with CF. Effective therapies are lacking. For progress to be made a better understanding of pathogenesis and disease detection are required.

PMID:35048397 | DOI:10.1111/apt.16749

Categories: Literature Watch

Case Report: Japanese Siblings of Cystic Fibrosis With a Novel Large Heterozygous Deletion in the CFTR Gene

Thu, 2022-01-20 06:00

Front Pediatr. 2022 Jan 3;9:800095. doi: 10.3389/fped.2021.800095. eCollection 2021.

ABSTRACT

Cystic fibrosis (CF) is a rare disease in the Japanese. The most common CFTR variant in Japanese CF patients is a large heterozygous deletion that can easily avoid detection by standard gene sequencing methods. We herein report a novel large heterozygous deletion in the CFTR gene in Japanese siblings with CF. A genetic analysis was performed in two patients (9-year-old boy and 5-month-old girl) who were clinically diagnosed with CF because of the positive result for the rapid fecal pancreatic elastase antigen test and the elevation of the sweat chloride concentration. In addition to conventional polymerase chain reaction (PCR) and direct sequencing, multiplex ligation-dependent probe amplification (MLPA) was performed to check for a large deletion and duplication of the CFTR gene. Based on MLPA findings, the breakpoint of heterozygous deletion was identified by real-time quantitative PCR followed by the sequence of the amplified junction fragment. In MLPA, the numbers of the fragments corresponding to exons 1, 16, 17a, and 17b and 234 nt and 747 nt upstream from the translation initiation codon of exon 1 in the CFTR gene and exon 3 in the ASZ1 gene were reduced by almost half. The c.2908+1085_3367+260del7201 variant (exon 16-17b deletion) was identified in one allele. The other allele had a large 137,567-bp deletion from g.117,361,112 (ASZ1 3' flanking region) to g.117,498,678 (CFTR intron 1) on chromosome 7. Since the deletion variant lacked the entire promoter region of CFTR, CFTR mRNA would not be transcribed from the allele, indicating it to be a novel pathogenic variant causing CF. As large mutations are frequently detected in Japanese CF patients, MPLA can be useful when searching for variants.

PMID:35047466 | PMC:PMC8762059 | DOI:10.3389/fped.2021.800095

Categories: Literature Watch

Identification of putative essential protein domains from high-density transposon insertion sequencing

Thu, 2022-01-20 06:00

Sci Rep. 2022 Jan 19;12(1):962. doi: 10.1038/s41598-022-05028-x.

ABSTRACT

A first clue to gene function can be obtained by examining whether a gene is required for life in certain standard conditions, that is, whether a gene is essential. In bacteria, essential genes are usually identified by high-density transposon mutagenesis followed by sequencing of insertion sites (Tn-seq). These studies assign the term "essential" to whole genes rather than the protein domain sequences that encode the essential functions. However, genes can code for multiple protein domains that evolve their functions independently. Therefore, when essential genes code for more than one protein domain, only one of them could be essential. In this study, we defined this subset of genes as "essential domain-containing" (EDC) genes. Using a Tn-seq data set built-in Burkholderia cenocepacia K56-2, we developed an in silico pipeline to identify EDC genes and the essential protein domains they encode. We found forty candidate EDC genes and demonstrated growth defect phenotypes using CRISPR interference (CRISPRi). This analysis included two knockdowns of genes encoding the protein domains of unknown function DUF2213 and DUF4148. These putative essential domains are conserved in more than two hundred bacterial species, including human and plant pathogens. Together, our study suggests that essentiality should be assigned to individual protein domains rather than genes, contributing to a first functional characterization of protein domains of unknown function.

PMID:35046497 | DOI:10.1038/s41598-022-05028-x

Categories: Literature Watch

Formation of Calprotectin-Derived Peptides in the Airways of Children with Cystic Fibrosis

Thu, 2022-01-20 06:00

J Immunol. 2022 Jan 19:ji2001017. doi: 10.4049/jimmunol.2001017. Online ahead of print.

ABSTRACT

Calprotectin is released by activated neutrophils along with myeloperoxidase (MPO) and proteases. It plays numerous roles in inflammation and infection, and is used as an inflammatory biomarker. However, calprotectin is readily oxidized by MPO-derived hypohalous acids to form covalent dimers of its S100A8 and S100A9 subunits. The dimers are susceptible to degradation by proteases. We show that detection of human calprotectin by ELISA declines markedly because of its oxidation by hypochlorous acid and subsequent degradation. Also, proteolysis liberates specific peptides from oxidized calprotectin that is present at inflammatory sites. We identified six calprotectin-derived peptides by mass spectrometry and detected them in the bronchoalveolar lavage fluid of children with cystic fibrosis (CF). We assessed the peptides as biomarkers of neutrophilic inflammation and infection. The content of the calprotectin peptide ILVI was related to calprotectin (r = 0.72, p = 0.01, n = 10). Four of the peptides were correlated with the concentration of MPO (r > 0.7, p ≤ 0.01, n = 21), while three were higher (p < 0.05) in neutrophil elastase-positive (n = 14) than -negative samples (n = 7). Also, five of the peptides were higher (p < 0.05) in the bronchoalveolar lavage fluid from children with CF with infections (n = 21) than from non-CF children without infections (n = 6). The specific peptides liberated from calprotectin will signal uncontrolled activity of proteases and MPO during inflammation. They may prove useful in tracking inflammation in respiratory diseases dominated by neutrophils, including coronavirus disease 2019.

PMID:35046105 | DOI:10.4049/jimmunol.2001017

Categories: Literature Watch

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