Dig Liver Dis. 2023 Aug 14:S1590-8658(23)00769-7. doi: 10.1016/j.dld.2023.07.017. Online ahead of print.

ABSTRACT

BACKGROUND AND AIMS: Foreign body ingestion (FBI) in children requires early identification to prevent adverse outcomes and may necessitate endoscopic or surgical intervention. This study aims to develop a nomogram that identifies children who require urgent surgical or endoscopic intervention by using the patient's medical history and clinical parameters collected at admission.

METHODS: This study is a retrospective review (01/2015-12/2020) of a multicenter case series of children admitted for FBI. Data from 5864 records from 24 hospitals in Italy were analyzed. Logistic regression models were used to establish the probability of requiring surgical or endoscopic intervention based on patient history and clinical characteristics. The nomogram representing the results from the multivariable model was reported to examine the propensity for surgery/endoscopy.

RESULTS: The study identified a significant association between intervention and various factors, including type of foreign body (blunt: reference category, disk battery (odds ratio OR:4.89), food bolus (OR:1.88), magnets (OR:2.61), sharp-pointed (OR:1.65), unknown (OR:1.02)), pre-existing diseases or conditions (OR 3.42), drooling (OR 10.91), dysphagia (OR 5.58), vomiting (OR 3.30), retrosternal pain (OR 5.59), abdominal pain (OR 1.58), hematemesis (OR 2.82), food refusal/poor feeding (OR 2.99), and unexplained crying (OR 2.01). The multivariable regression model showed good calibration and discrimination ability, with an area under the ROC curve of 0.77.

CONCLUSIONS: This study developed the first nomogram to predict the probability of the need for surgical or endoscopic intervention in children with FBI, based on the information collected at admission. The nomogram will aid clinicians in identifying children who require early intervention to prevent adverse outcomes.

PMID:37586909 | DOI:10.1016/j.dld.2023.07.017

Braz J Med Biol Res. 2023 Aug 14;56:e12752. doi: 10.1590/1414-431X2023e12752. eCollection 2023.

ABSTRACT

There is little information on pulmonary rehabilitation in patients with cystic fibrosis (CF) with pulmonary exacerbation. This study aimed to evaluate the effects of an early rehabilitation program on lung function, muscle strength, inflammatory markers, and quality of life in adults with CF hospitalized for pulmonary exacerbation. In this randomized controlled trial, 19 patients were included in the intervention group and 15 in the control group. The intervention group underwent an early rehabilitation program for 14 days after admission. All patients underwent spirometry, one-repetition maximum tests (1RM), and the 6-min walk test, and answered the Revised Cystic Fibrosis Questionnaire (CFQ-R) for quality of life and the International Physical Activity Questionnaire. Serum levels of interleukin and tumor necrosis factor alpha (TNF-α) were measured. In the intervention group, there were increases in 1RM biceps (P=0.009), triceps (P=0.005), shoulder abductors (P=0.002), shoulder flexors (P=0.004), hamstrings (P<0.001), and quadriceps values (P<0.001). In addition, there were improvements in CFQ-R-emotion (P=0.002), treatment burden (P=0.002), vitality (P=0.011), and physical scores (P=0.026), and a reduction in the Borg resting fatigue score (P=0.037). The interleukins levels did not change after the intervention. In adult CF patients with pulmonary exacerbation, early hospital rehabilitation had a significant impact on improving resting fatigue, muscle strength, and quality of life.

PMID:37585917 | DOI:10.1590/1414-431X2023e12752

World J Clin Cases. 2023 Jul 26;11(21):4996-5013. doi: 10.12998/wjcc.v11.i21.4996.

ABSTRACT

The asthmatic inflammatory process results in the generation of volatile organic compounds (VOCs), which are subsequently secreted by the airways. The study of these elements through gas chromatography-mass spectrometry (GC-MS), which can identify individual molecules with a discriminatory capacity of over 85%, and electronic-Nose (e-NOSE), which is able to perform a quick onboard pattern-recognition analysis of VOCs, has allowed new prospects for non-invasive analysis of the disease in an "omics" approach. In this review, we aim to collect and compare the progress made in VOCs analysis using the two methods and their instrumental characteristics. Studies have described the potential of GC-MS and e-NOSE in a multitude of relevant aspects of the disease in both children and adults, as well as differential diagnosis between asthma and other conditions such as wheezing, cystic fibrosis, COPD, allergic rhinitis and last but not least, the accuracy of these methods compared to other diagnostic tools such as lung function, FeNO and eosinophil count. Due to significant limitations of both methods, it is still necessary to improve and standardize techniques. Currently, e-NOSE appears to be the most promising aid in clinical practice, whereas GC-MS, as the gold standard for the structural analysis of molecules, remains an essential tool in terms of research for further studies on the pathophysiologic pathways of the asthmatic inflammatory process. In conclusion, the study of VOCs through GC-MS and e-NOSE appears to hold promise for the non-invasive diagnosis, assessment, and monitoring of asthma, as well as for further research studies on the disease.

PMID:37583852 | PMC:PMC10424019 | DOI:10.12998/wjcc.v11.i21.4996

ACS Med Chem Lett. 2023 Jul 28;14(8):1049-1053. doi: 10.1021/acsmedchemlett.3c00046. eCollection 2023 Aug 10.

ABSTRACT

4'-Methyl-4,5'-bithiazoles were previously identified as cystic fibrosis transmembrane regulator (CFTR) correctors, thus being able to correct folding defective mutants of the channel regulating chloride transport through the membrane. Additionally, bithiazole derivative C17 was reported to recover α-sarcoglycan in vitro and in vivo. We report here the synthesis of two new derivatives of C17, in which the two sides of the bithiazole scaffold were modified. The synthesized compounds and the corresponding precursors were tested in myogenic cells to evaluate the expression of α-sarcoglycan. The results highlighted that both substitutions of the bithiazole scaffold are important to achieve the maximum recovery of the α-sarcoglycan mutant. Nonetheless, partial preservation of the activity was observed. Accordingly, this paves the way to further derivatizations/optimization and target fishing studies, which were preliminarily performed in this study as a proof of concept, allowing the investigation of the molecular mechanisms leading to the α-sarcoglycan correction.

PMID:37583821 | PMC:PMC10424318 | DOI:10.1021/acsmedchemlett.3c00046

J Clin Invest. 2023 Aug 15:e163402. doi: 10.1172/JCI163402. Online ahead of print.

ABSTRACT

Secondary lung infection by inhaled Staphylococcus aureus (SA) is a common and lethal event in individuals infected with influenza A virus (IAV). How IAV disrupts host defense to promote SA infection in lung alveoli, where fatal lung injury occurs, is not known. We addressed this issue using the first real-time determinations of alveolar responses to IAV in live, intact, perfused lungs. Our findings show IAV infection blocked defensive alveolar wall liquid (AWL) secretion and induced airspace liquid absorption, thereby reversing normal alveolar liquid dynamics and inhibiting alveolar clearance of inhaled SA. Loss of AWL secretion resulted from inhibition of the cystic fibrosis transmembrane conductance regulator (CFTR) ion channel in the alveolar epithelium, and airspace liquid absorption was caused by stimulation of the alveolar epithelial Na+ channel (ENaC). Loss of AWL secretion promoted alveolar stabilization of inhaled SA, but rescue of AWL secretion protected against alveolar SA stabilization and fatal SA-induced lung injury in IAV-infected mice. These findings reveal a central role for AWL secretion in alveolar defense against inhaled SA and identify AWL inhibition as a critical mechanism of IAV lung pathogenesis. AWL rescue may represent a new therapeutic approach for IAV-SA coinfection.

PMID:37581936 | DOI:10.1172/JCI163402

J Clin Invest. 2023 Aug 15:e171268. doi: 10.1172/JCI171268. Online ahead of print.

ABSTRACT

The volume and composition of a thin layer of liquid covering the airway surface defend the lung from inhaled pathogens and debris. Airway epithelia secrete Cl- into the airway surface liquid through CFTR (cystic fibrosis transmembrane conductance regulator) channels, thereby increasing the volume of airway surface liquid. The discovery that pulmonary ionocytes contain high levels of CFTR led us to predict that ionocytes drive secretion. However, we found the opposite. Elevating ionocyte abundance increased liquid absorption, whereas reducing ionocyte abundance increased secretion. In contrast to other airway epithelial cells, ionocytes contained barttin/Cl- channels in their basolateral membrane. Disrupting barttin/Cl- channel function impaired liquid absorption, and overexpressing barttin/Cl- channels increased absorption. Together, apical CFTR and basolateral barttin/Cl- channels provide an electrically conductive pathway for Cl- flow through ionocytes, and the transepithelial voltage generated by apical Na+ channels drives absorption. These findings indicate that ionocytes mediate liquid absorption, and secretory cells mediate liquid secretion. Segregating these counteracting activities to distinct cell types enables epithelia to precisely control the airway surface. Moreover, the divergent role of CFTR in ionocytes and secretory cells suggests that cystic fibrosis disrupts both liquid secretion and absorption.

PMID:37581935 | DOI:10.1172/JCI171268

CMAJ. 2023 Aug 14;195(31):E1040. doi: 10.1503/cmaj.230583.

NO ABSTRACT

PMID:37580078 | DOI:10.1503/cmaj.230583

J Innate Immun. 2023 Aug 14. doi: 10.1159/000533606. Online ahead of print.

ABSTRACT

SARS-CoV-2 utilizes receptor binding domain (RBD) of spike glycoprotein to interact with angiotensin-converting enzyme 2 (ACE2). Decreased cell surface density of ACE2 contributes to mortality during COVID-19. Studies published early during the pandemic reported that people with cystic fibrosis (PwCF) treated with the high efficiency CFTR modulators ETI (elexacaftor-tezacaftor-ivacaftor) had higher ACE2 levels and milder COVID-19 symptoms, compared to people without CF. Subsequent studies did not confirm these findings. TGF-β1 gene polymorphisms associated with higher TGF-β1 levels, present in approximately 40% of CF patients, lead to more severe CF lung disease. To understand whether TGF-β1 modulates COVID-19 severity by affecting ACE2 levels in the airway, we performed small RNAseq and microRNA profiling and identified pathways uniquely affected by TGF-β1, including those associated with SARS-CoV-2 invasion. TGF-β1 inhibited ACE2 expression by miR-136-3p and miR-369-5p. ACE2 levels were higher in CF bronchial epithelial cell models. ETI did not prevent TGF-β1 inhibition of ACE2. Finally, TGF-β1 reduced the interaction between ACE2 and RBD by lowering ACE2 levels and its binding to RBD. Our data demonstrate novel mechanism whereby TGF-β1 inhibition of ACE2 in CF and non-CF bronchial epithelia may modulate SARS-CoV-2 pathogenicity and COVID-19 severity. By reducing ACE2 levels, TGF-β1 may decrease entry of SARS-CoV-2 into host cells while hindering recovery from COVID-19 due to loss of anti-inflammatory effects of ACE2.

PMID:37579743 | DOI:10.1159/000533606

Ann Am Thorac Soc. 2023 Aug 14. doi: 10.1513/AnnalsATS.202302-168OC. Online ahead of print.

ABSTRACT

RATIONALE: Magnetic resonance imaging (MRI) detects improvements in mucus plugging and bronchial wall thickening, but not in lung perfusion in patients with cystic fibrosis (CF) treated with elexacaftor/tezacaftor/ivacaftor (ETI).

OBJECTIVE(S): To determine whether bronchial artery dilatation (BAD), a key feature of advanced lung disease, indicates irreversibility of perfusion abnormalities and whether BAD could be reversed in CF patients treated with ETI.

METHODS: 59 adults with CF underwent longitudinal chest MRI including MR angiography (MRA) twice, 35 CF patients (mean age 31±7y) before (MRI1) and after (MRI2) at least one month (mean duration 8±4mon) on ETI therapy and 24 control CF patients (mean age 31±7y) without ETI. MRI was assessed using the validated chest MRI score, and presence and total lumen area of BAD were assessed with commercial software.

RESULTS: The MRI global score was stable in the control group from MRI1 to MRI 2 (mean difference: 1.1 [-0.3, 2.4], P=0.054), but was reduced in the ETI group (-10.1 [-0.3, 2.4], P<0.001). In the control as well as in the ETI group, BAD was present in almost all patients at baseline (95% and 94%, respectively) which did not change at MRI2. The BAD total lumen area did not change in the control group from MRI1 to MRI2 (1.0 mm2 [-0.2, 2.2], P=0.099), but decreased in the ETI group (-7.0 mm2 [-8.9, -5.0], P<0.001). This decrease correlated with improvements in the MRI global score (r=0.540, P<0.001).

CONCLUSIONS: Our data show that BAD may be partially reversible under ETI therapy in adult CF patients with established disease.

PMID:37579262 | DOI:10.1513/AnnalsATS.202302-168OC

bioRxiv. 2023 Aug 2:2023.08.02.551661. doi: 10.1101/2023.08.02.551661. Preprint.

ABSTRACT

Critical Gram-negative pathogens, like Pseudomonas , Stenotrophomonas and Burkholderia , have become resistant to most antibiotics. Complex resistance profiles together with synergistic interactions between these organisms increase the likelihood of treatment failure in distinct infection settings, for example in the lungs of cystic fibrosis patients. Here, we discover that cell envelope protein homeostasis pathways underpin both antibiotic resistance and cross-protection in CF-associated bacteria. We find that inhibition of oxidative protein folding inactivates multiple species-specific resistance proteins. Using this strategy, we sensitize multi-drug resistant Pseudomonas aeruginosa to β-lactam antibiotics and demonstrate promise of new treatment avenues for the recalcitrant pathogen Stenotrophomonas maltophilia . The same approach also inhibits cross-protection between resistant S. maltophilia and susceptible P. aeruginosa , allowing eradication of both commonly co-occurring CF-associated organisms. Our results provide the basis for the development of next-generation strategies that target antibiotic resistance, while also impairing specific interbacterial interactions that enhance the severity of polymicrobial infections.

PMID:37577508 | PMC:PMC10418187 | DOI:10.1101/2023.08.02.551661

bioRxiv. 2023 Aug 2:2023.08.01.551570. doi: 10.1101/2023.08.01.551570. Preprint.

ABSTRACT

The gut physiology of pediatric and adult persons with cystic fibrosis (pwCF) is altered relative to healthy persons. The CF gut is characterized, in part, as having excess mucus, increased fat content, acidic pH, increased inflammation, increased antibiotic perturbation and the potential for increased oxygen availability. These physiological differences shift nutritional availability and the local environment for intestinal microbes, thus likely driving significant changes in microbial metabolism, colonization and competition with other microbes. The impact of any specific change in this physiological landscape is difficult to parse using human or animal studies. Thus, we have developed a novel culture medium representative of the CF gut environment, inclusive of all the aforementioned features. This medium, called CF-MiPro, maintains CF gut microbiome communities, while significantly shifting non-CF gut microbiome communities toward a CF-like microbial profile, characterized by low Bacteroidetes and high Proteobacteria abundance. This medium is able to maintain this culture composition for up to 5 days of passage. Additionally, microbial communities passaged in CF-MiPro produce significantly less immunomodulatory short chain fatty acids (SCFA), including propionate and butyrate, than communities passaged in MiPro, a culture medium representative of healthy gut physiology, confirming not only a shift in microbial composition but altered community function. Our results support the potential for this in vitro culture medium as a new tool for the study of gut dysbiosis in CF.

IMPORTANCE: Cystic fibrosis is an autosomal recessive disease that disrupts ion transport at mucosal surfaces, leading to mucus accumulation and altered physiology of both the lungs and the intestines, among other organs, with the resulting altered environment contributing to an imbalance of microbial communities. Culture media representative of the CF airway have been developed and validated; however, no such medium exists for modeling the CF intestine. Here, we develop and validate a first-generation culture medium inclusive of features that are altered in the CF colon. Our findings suggest this novel medium, called CF-MiPro, as a maintenance medium for CF gut microbiome samples and a flexible tool for studying key drivers of CF-associated gut dysbiosis.

PMID:37577487 | PMC:PMC10418193 | DOI:10.1101/2023.08.01.551570

Front Cell Infect Microbiol. 2023 Jul 27;13:1234420. doi: 10.3389/fcimb.2023.1234420. eCollection 2023.

ABSTRACT

Pseudomonas aeruginosa TBCF10839 is a highly virulent strain that can persist and replicate in human neutrophils. Screening of a signature-tagged mutagenesis (STM) TBCF10839 transposon library in phagocytosis tests identified a mutant that carried the transposon in the VirB4 homolog 5PG21 of an integrative and conjugative element (ICE)-associated type IV secretion system of the pKLC102 subtype. 5P21 TBCF10839 insertion mutants were deficient in metabolic versatility, secretion, quorum sensing, and virulence. The mutants were efficiently killed in phagocytosis tests in vitro and were avirulent in an acute murine airway infection model in vivo. The inactivation of 5PG21 silenced the rhl, las, and pqs operons and the gene expression for the synthesis of hydrogen cyanide, the antimetabolite l-2-amino-4-methoxy-trans-3-butenoic acid, and the H2- and H3-type VI secretion systems and their associated effectors. The mutants were impaired in the utilization of carbon sources and stored compounds that are not funneled into intermediary metabolism. This showcase demonstrates that a single gene of the mobile accessory genome can become an essential element to operate the core genome-encoded features of metabolism and virulence.

PMID:37577372 | PMC:PMC10413270 | DOI:10.3389/fcimb.2023.1234420

Open Forum Infect Dis. 2023 Aug 10;10(8):ofad369. doi: 10.1093/ofid/ofad369. eCollection 2023 Aug.

ABSTRACT

BACKGROUND: Therapeutically immunosuppressed transplant recipients exhibit attenuated responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines. To elucidate the kinetics and variant cross-protection of vaccine-induced antibodies in this population, we conducted a prospective longitudinal study in heart and lung transplant recipients receiving the SARS-CoV-2 messenger RNA (mRNA) 3-dose vaccination series.

METHODS: We measured longitudinal serum antibody and neutralization responses against the ancestral and major variants of SARS-CoV-2 in SARS-CoV-2-uninfected lung (n = 18) and heart (n = 17) transplant recipients, non-lung-transplanted patients with cystic fibrosis (n = 7), and healthy controls (n = 12) before, during, and after the primary mRNA vaccination series.

RESULTS: Among healthy controls, strong anti-spike responses arose immediately following vaccination and displayed cross-neutralization against all variants. In contrast, among transplant recipients, after the first 2 vaccine doses, increases in antibody concentrations occurred gradually, and cross-neutralization was completely absent against the Omicron B.1.1.529 variant. However, most (73%) of the transplant recipients had a significant response to the third vaccine dose, reaching levels comparable to those of healthy controls, with improved but attenuated neutralization of immune evasive variants, particularly Beta, Gamma, and Omicron. Responses in non-lung-transplanted patients with cystic fibrosis paralleled those in healthy controls.

CONCLUSIONS: In this prospective, longitudinal analysis of variant-specific antibody responses, lung and heart transplant recipients display delayed and defective responses to the first 2 SARS-CoV-2 vaccine doses but significantly augmented responses to a third dose. Gaps in antibody-mediated immunity among transplant recipients are compounded by decreased neutralization against Omicron variants, leaving many patients with substantially weakened immunity against currently circulating variants.

PMID:37577118 | PMC:PMC10414143 | DOI:10.1093/ofid/ofad369

Balkan J Med Genet. 2023 Jul 31;26(1):83-88. doi: 10.2478/bjmg-2023-0001. eCollection 2023 Jul.

ABSTRACT

Pre-implantation genetic diagnosis (PGD) is not often performed when donor gametes are used, due to its high cost. This is with the presumption that the donors are healthy. We report on five cases of babies with confirmed cystic fibrosis (CF), being the result from in vitro fertilization (IVF) with donor (4 cases) or own gametes (one case). There has been no family history for CF in any of the families affected. The clinical presentation in the children ranged from meconium ileus to recurrent respiratory infections and severe nasal polyposis. The age of diagnosis also varied from birth until 9 years. Since one of the presented cases was discovered in a very renowned private IVF clinic, the clinic changed their own protocol, and currently they test every donor for CF carriership. The percentage of CF carriers in the donor population is roughly the same as the one predicted in the general population of Bulgaria - 1/33. Although PGD is costly, the costs for proper care for a CF patient are currently much higher. The more economical option would to screen every donor for CF carriership. IVF requires a lot of physical and psychological stamina. The couples that go through this procedure also require a great deal of hope. It is essential to be more preconscious for possible congenital diseases. We advocate every IVF center to test the donors for CF carriership or to provide PGD for their clients.

PMID:37576787 | PMC:PMC10413990 | DOI:10.2478/bjmg-2023-0001

Cureus. 2023 Jul 11;15(7):e41697. doi: 10.7759/cureus.41697. eCollection 2023 Jul.

ABSTRACT

Cystic fibrosis (CF) is an autosomal recessive genetic disorder resulting from defects in the cystic fibrosis transmembrane conductance regulator (CFTR) protein, which in turn results in a multi-systemic disorder. There are numerous known CF alleles associated with different mutations of the CFTR gene, with the most common CF allele being a three-base-pair deletion known as ΔF508. One common manifestation of CF is glycemic dysregulation associated with decreased insulin secretion, often progressing into a distinct form of diabetes known as cystic fibrosis-related diabetes (CFRD). In the past decade, a class of drugs known as CFTR modulators has entered clinical practice. These drugs interact with the CFTR protein to restore its function, with different modulators (or combinations of modulators) suitable for patients with different CFTR mutations. Previous research has established that the modulator ivacaftor is effective in decreasing blood glucose and sometimes resolving CFRD in patients with certain CFTR mutations (class III mutations). However, early modulator therapies for individuals with the common ΔF508 mutation (e.g., a combination of the modulators lumacaftor and ivacaftor) have largely proven ineffective in improving glucose regulation. More recently, a combination therapy of three modulators, namely elexacaftor, tezacaftor, and ivacaftor (ETI), has entered clinical practice for patients with the ΔF508 mutation. However, it is not clear whether this therapy is effective in treating dysglycemia. We searched for studies of any design that examined the effects of ETI on measures of blood glucose. All available studies were observational studies comparing patients before and after initiating ETI therapy. Measures of daily-life blood glucose (those obtained with continuous glucose monitoring systems or by measuring glycated hemoglobin (HbA1c)) and post-prandial glucose spikes from oral glucose tolerance tests showed significant improvements in at least some studies. The majority of studies showed significant improvements from pre- to post-ETI in one or more blood glucose measures. While the interpretation of this evidence is complicated by the lack of randomized controlled trials, it appears that ETI therapy is associated with improved glucose regulation for at least some patients with the ΔF508 mutation.

PMID:37575762 | PMC:PMC10413995 | DOI:10.7759/cureus.41697

Pulm Pharmacol Ther. 2023 Aug 11:102247. doi: 10.1016/j.pupt.2023.102247. Online ahead of print.

ABSTRACT

BACKGROUND: Recent advances in CFTR modulator therapy have the potential to change the face of cystic fibrosis (CF). This retrospective observational study describes real world experience of the four available CFTR modulators in adults and children with CF in a single centre in Melbourne, Australia.

METHOD: Data was collected for all patients treated with CFTR modulators at MonashCF between May 2012 and September 2020. Primary outcomes included lung function, admission days and BMI/BMI centile over time. Adverse events and reasons for changing or ceasing medications were also analysed.

RESULTS: 55% (74/133) adult and 46% (55/119) paediatric patients were treated with CFTR modulators. FEV1 increased in adults treated with ivacaftor (IVA) and elexacaftor/tezacaftor/ivacaftor (ELX/TEZ/IVA) by 4.73% and 10.07% respectively, and BMI also improved in these groups. Nutrition improved in adults and children treated with lumacaftor/ivacaftor (LUM/IVA). There was no significant improvement in FEV1 or admission days with LUM/IVA or tezacaftor/ivacaftor (TEZ/IVA). 36% (31/85) ceased LUM/IVA, due to adverse effects in 81% (25/31). Of these, 92% (23/25) changed to TEZ/IVA, 78% (18/23) without significant adverse effects.

CONCLUSIONS: Our findings for LUM/IVA and TEZ/IVA are less encouraging than those seen in clinical trials, with no significant improvement in lung function or admission days and a higher rate of adverse effects with LUM/IVA compared with phase 3 clinical trials. TEZ/IVA was generally well tolerated by those who experienced side effects with LUM/IVA. The small number of patients treated with ELX/TEZ/IVA had improvements in all parameters. These findings support ongoing use of IVA for individuals with gating mutations, and transition to ELX/TEZ/IVA once available for patients with at least one Phe508del mutation.

PMID:37574040 | DOI:10.1016/j.pupt.2023.102247

Chem Biol Interact. 2023 Aug 11:110657. doi: 10.1016/j.cbi.2023.110657. Online ahead of print.

ABSTRACT

The problem of biofilm formation is a serious concern under various pathological conditions such as extensive burns, wounds in diabetic patients, bedsores, cystic fibrosis, nosocomial infections from implantable medical devices such as catheters, valves, etc. Environmental diffusion of biofilm (in pools, wet floors, industrial food plants) that could represent a reservoir of antibiotic resistant bacteria constitues an additional issue. In this work is described a lactonase from Rhodococcus erythropolis, a phosphotriesterase-like lactonase (PLL) enzyme, which has already been studied in the past and can be used for containment of biofilm formation. The protein is 28% and 40% identical with respect to the Pseudomonas diminuta PTE and the thermostable Saccharolobus solfataricus SsoPox respectively. The protein was obtained starting from a synthetic His-tagged gene, expressed in E. coli, purified and further characterized. New properties, not previously known or deducible from its sequence, have been highlighted. These properties are: the enzyme is thermophilic and thermostable even though it originates from a mesophilic bacterium; the enzyme has a long (months) shelf life at 4 °C; the enzyme is not only stable to low concentrations of the oxidant H2O2 but even activated by it at high concentrations; the enzyme proved to be a proficient quorum quenching enzyme, able to hydrolase acyl-homoserine lactones 3oxoC12-HSL and C4-HSL, and can inhibit up to 60% the formation of Pseudomonas aeruginosa (PAO1) biofilm. These different properties make the lactonase useful to fight resistant bacteria that induce inflammatory and infectious processes mediated by the quorum sensing mechanism.

PMID:37573927 | DOI:10.1016/j.cbi.2023.110657

Mol Genet Metab. 2023 Aug 6:107679. doi: 10.1016/j.ymgme.2023.107679. Online ahead of print.

ABSTRACT

This Commentary summarizes what the author has learned in 46 years of research on newborn screening (NBS) for cystic fibrosis (CF) combined with healthcare and public health practice. The original expectation was that screening for this relatively common, life-threatening genetic disorder would lead to consistently timely diagnoses in the neonatal period and be equitable. Unfortunately, this ambitious goal has not been achieved in the USA despite the availability of an excellent, although imperfect, 2-tiered screening test employing immunoreactive trypsinogen (IRT) and DNA analysis for pathogenic variants in the gene that encodes the cystic fibrosis transmembrane conductance regulator (CFTR). In fact, variations in the quality of NBS programs, inconsistencies in their operations, and disparities in outcomes have been prominent features. The causes include leadership challenges and deficiencies among both CF centers and NBS labs; failures to form effective partnerships among CF centers and with NBS programs; relatively rapid implementation after 2005 with variable quality planning; misunderstandings and erroneous dogma about CF; data limitations regarding IRT, especially cutoff values, and CFTR genetics; tolerance of suboptimal protocols and false negative results; problems in dried blood spot collections plus a lack of transparency and national oversight; partial lack of readiness, qualifications, funding and/or willingness to innovate with floating IRT cutoffs and DNA/CFTR analyses; follow up challenges/deficiencies impairing timeliness, including sweat testing limitations; and published guidelines that are more descriptive than sufficiently critical and directive. But the lessons learned through uniquely intensive CF NBS research have been enlightening and guided the U.S. Cystic Fibrosis Foundation to nationwide quality improvement initiatives.

PMID:37573205 | DOI:10.1016/j.ymgme.2023.107679

Sleep Med. 2023 Jul 29;110:106-110. doi: 10.1016/j.sleep.2023.07.024. Online ahead of print.

ABSTRACT

BACKGROUND: Spinal muscular atrophy (SMA) is a severe neuromuscular disorder, the phenotype of the disease is caused by the mutation of the SMN1 (survival motor neuron 1) gene which encodes for the SMN protein. Innovative treatments for SMA have become available and the first molecule approved is Nusinersen, an antisense oligonucleotide that increases the production of SMN protein. Nusinersen has been shown to be associated with a significant motor improvement and an increase of the event-free survival. For these reasons the aim of the present study is to assess if Nusinersen is able modify sleep architecture and microstructure and to improve sleep structure in these patients.

METHODS: Sixteen patients affected by SMA1 were enrolled in the study (4 boys, 12 girls; median age 72.5 months, intelligence quotient range 24-84). All patients underwent complete nocturnal PSG before the start of the treatment trough intrathecal injections with Nusinersen (T0) and after the fifth infusion (day 180, T180). PSG recordings were visually scored and interpreted according to the indications of the American Academy of Sleep Medicine (AASM) and and microstructure by means of the Cyclic Alternating Pattern (CAP).

RESULTS: After 6 months therapy we found a significantly reduced sleep latency and a significantly increased sleep efficiency. Regarding sleep microstructure parameters (CAP), we did not find any significant change after therapy however, it is worth mentioning that a moderate effect size was observed for the increase in CAP A3 index.

CONCLUSIONS: We observed short-term effects of Nusinersen on sleep with an improvement in sleep efficiency and reduction in sleep onset latency; regarding sleep microstructure, a moderate effect size was found for the number of CAP A3 subtypes that slightly increased, possibly indicating a slightly higher arousability. This finding points at a probably overall better sleep pattern organization associated with the treatment, but they need to be confirmed by larger studies with patients treated earlier in life and for a longer period.

PMID:37572575 | DOI:10.1016/j.sleep.2023.07.024

Int J Mol Sci. 2023 Aug 6;24(15):12496. doi: 10.3390/ijms241512496.

ABSTRACT

Pseudomonas aeruginosa is an opportunistic Gram-negative bacterium responsible for severe nosocomial infections and is considered a critical pulmonary pathogen for both immunocompromised and cystic fibrosis patients. Planktonic cells of P. aeruginosa possess intrinsic and acquired resistances, inactivating several classes of conventional antibiotics. Additionally, this bacterium can grow, forming biofilms, and complex structures, further hampering the action of multiple antibiotics. Here, we report the biological properties of D-Q53 CecB, an all-D enantiomer of the silkworm natural peptide Q53 CecB. Compared to the L-variant, D-Q53 CecB was resistant to in vitro degradation by humans and P. aeruginosa elastases and showed an enhanced bactericidal activity against P. aeruginosa planktonic bacteria. D-Q53 CecB was thermostable and maintained its antimicrobial activity at high salt concentrations and in the presence of divalent cations or fetal-bovine serum, although at reduced levels. Against different types of human cells, D-Q53 CecB showed cytotoxic phenomena at concentrations several folds higher compared to those active against P. aeruginosa. When L- and D-Q53 CecB were compared for their antibiofilm properties, both peptides were active in inhibiting biofilm formation. However, the D-enantiomer was extremely effective in inducing biofilm degradation, suggesting this peptide as a favorable candidate in an anti-Pseudomonas therapy.

PMID:37569868 | DOI:10.3390/ijms241512496