Active microscopic colitis precipitated by fluoxetine.

Microscopic colitis is a form of chronic and recurrent inflammatory bowel disease characterized by non-bloody, watery diarrhea, macroscopically normal colonic mucosa, and characteristic histopathological findings. Some drugs have been described as triggers of colonic inflammation in predisposed individuals, while others may exacerbate microscopic colitis that evolves on its own. We present the case of a patient diagnosed with active microscopic colitis in relation to taking fluoxetine at high doses.

Pf bacteriophages hinder sputum antibiotic diffusion via electrostatic binding.

Despite great progress in the field, chronic Pseudomonas aeruginosa (Pa) infections remain a major cause of morbidity and mortality in patients with cystic fibrosis, necessitating treatment with inhaled antibiotics. Pf phage is a filamentous bacteriophage produced by Pa that has been reported to act as a structural element in Pa biofilms. Pf presence has been associated with resistance to antibiotics and poor outcomes in cystic fibrosis, though the underlying mechanisms are unclear. Here, we have investigated how Pf phages and sputum biopolymers impede antibiotic diffusion using human sputum samples and fluorescent recovery after photobleaching. We demonstrate that tobramycin interacts with Pf phages and sputum polymers through electrostatic interactions. We also developed a set of mathematical models to analyze the complex observations. Our analysis suggests that Pf phages in sputum reduce the diffusion of charged antibiotics due to a greater binding constant associated with organized liquid crystalline structures formed between Pf phages and sputum polymers. This study provides insights into antibiotic tolerance mechanisms in chronic Pa infections and may offer potential strategies for novel therapeutic approaches.

Prolapsed hyperplastic gastric polyp: an uncommon cause of acute pancreatitis.

A 68-year-old male presented to the Emergency Department with a one-month history of intermittent epigastrium pain. Laboratory tests revealed leukocytosis and elevated lipase (4129 UI/l), with normal liver function, so he was admitted for its first episode of acute pancreatitis. Abdominal ultrasound showed liver steatosis, without cholelithiasis or bile duct dilatation. A thoraco-abdominal computed tomography was performed, revealing a pedunculated gastric polyp in lesser curvature measuring 64x38mm with no evidence of metastatic disease. Gastroscopy was performed, showing a 7-cm pedunculated gastric polyp prolapsed through the pylorus into the duodenum. The polyp was moved into the stomach, and a fragmented resection of the polyp was carried out with a hot snare. Histopathologic evaluation was compatible with hyperplastic polyp with low-grade dysplasia. The patient had a favourable evolution with no complications after the procedure.

Clinical and functional spectrum of RAC2-related immunodeficiency.

ABSTRACT: Mutations in the small Rho-family guanosine triphosphate hydrolase RAC2, critical for actin cytoskeleton remodeling and intracellular signal transduction, are associated with neonatal severe combined immunodeficiency (SCID), infantile neutrophilic disorder resembling leukocyte adhesion deficiency (LAD), and later-onset combined immune deficiency (CID). We investigated 54 patients (23 previously reported) from 37 families yielding 15 novel RAC2 missense mutations, including one present only in homozygosity. Data were collected from referring physicians and literature reports with updated clinical information. Patients were grouped by presentation: neonatal SCID (n = 5), infantile LAD-like disease (n = 5), or CID (n = 44). Disease correlated to RAC2 activity: constitutively active RAS-like mutations caused neonatal SCID, dominant-negative mutations caused LAD-like disease, whereas dominant-activating mutations caused CID. Significant T- and B-lymphopenia with low immunoglobulins were seen in most patients; myeloid abnormalities included neutropenia, altered oxidative burst, impaired neutrophil migration, and visible neutrophil macropinosomes. Among 42 patients with CID with clinical data, upper and lower respiratory infections and viral infections were common. Twenty-three distinct RAC2 mutations, including 15 novel variants, were identified. Using heterologous expression systems, we assessed downstream effector functions including superoxide production, p21-activated kinase 1 binding, AKT activation, and protein stability. Confocal microscopy showed altered actin assembly evidenced by membrane ruffling and macropinosomes. Altered protein localization and aggregation were observed. All tested RAC2 mutant proteins exhibited aberrant function; no single assay was sufficient to determine functional consequence. Most mutants produced elevated superoxide; mutations unable to support superoxide formation were associated with bacterial infections. RAC2 mutations cause a spectrum of immune dysfunction, ranging from early onset SCID to later-onset combined immunodeficiencies depending on RAC2 activity. This trial was registered at www.clinicaltrials.gov as #NCT00001355 and #NCT00001467.

The Inovirus Pf4 Triggers Antiviral Responses and Disrupts the Proliferation of Airway Basal Epithelial Cells.

BACKGROUND: The inovirus Pf4 is a lysogenic bacteriophage of Pseudomonas aeruginosa (Pa). People with Cystic Fibrosis (pwCF) experience chronic airway infection with Pa and a significant proportion have high numbers of Pf4 in their airway secretions. Given the known severe damage in the airways of Pa-infected pwCF, we hypothesized a high Pf4 burden can affect airway healing and inflammatory responses. In the airway, basal epithelial cells (BCs) are a multipotent stem cell population critical to epithelium homeostasis and repair. We sought to investigate the transcriptional responses of BCs under conditions that emulate infection with Pa and exposure to high Pf4 burden. METHODS: Primary BCs isolated from pwCF and wild-type (WT) donors were cultured in vitro and exposed to Pf4 or bacterial Lipopolysaccharide (LPS) followed by transcriptomic and functional assays. RESULTS: We found that BCs internalized Pf4 and this elicits a strong antiviral response as well as neutrophil chemokine production. Further, we found that BCs that take up Pf4 demonstrate defective migration and proliferation. CONCLUSIONS: Our findings are highly suggestive of Pf4 playing a role in the pathogenicity of Pa in the airways. These findings provide additional evidence for the ability of inoviruses to interact with mammalian cells and disrupt cell function.

The challenges and promise of sweat sensing.

The potential of monitoring biomarkers in sweat for health-related applications has spurred rapid growth in the field of wearable sweat sensors over the past decade. Some of the key challenges have been addressed, including measuring sweat-secretion rate and collecting sufficient sample volumes for real-time, continuous molecular analysis without intense exercise. However, except for assessment of cystic fibrosis and regional nerve function, the ability to accurately measure analytes of interest and their physiological relevance to health metrics remain to be determined. Although sweat is not a crystal ball into every aspect of human health, we expect sweat measurements to continue making inroads into niche applications involving active sweating, such as hydration monitoring for athletes and physical laborers and later for medical and casual health monitoring of relevant drugs and hormones.

Situs Ambiguus Is Associated With Adverse Clinical Outcomes in Children With Primary Ciliary Dyskinesia.

BACKGROUND: Primary ciliary dyskinesia (PCD) is a rare disorder of motile cilia associated with situs abnormalities. At least 12% of patients with PCD have situs ambiguus (SA), including organ laterality defects falling outside normal arrangement (situs solitus [SS]) or mirror image inversion (situs inversus totalis [SIT]). RESEARCH QUESTION: Do patients with PCD and SA achieve worse clinical outcomes compared with those with SS or SIT? STUDY DESIGN AND METHODS: This cross-sectional, multicenter study evaluated participants aged 21 years or younger with PCD. Participants were classified as having SA, including heterotaxy, or not having SA (SS or SIT). Markers of disease severity were compared between situs groups, adjusting for age at enrollment and severe CCDC39 or CCDC40 genotype, using generalized linear models and logistic and Poisson regression. RESULTS: In 397 participants with PCD (mean age, 8.4 years; range, 0.1-21), 42 patients were classified as having SA, including 16 patients (38%) with complex cardiovascular malformations or atrial isomerism, 13 patients (31%) with simple CVM, and 13 patients (31%) without cardiovascular malformations. Of these, 15 patients (36%) underwent cardiac surgery, 24 patients (57%) showed an anatomic spleen abnormality, and seven patients (17%) showed both. The remaining 355 participants did not have SA, including 152 with SIT and 203 with SS. Overall, 70 participants (17%) harbored the severe CCDC39 or CCDC40 genotype. Compared with participants without SA, those with SA showed lower median BMI z scores (P = .03), lower FVC z scores (P = .01), and more hospitalizations and IV antibiotic courses for acute respiratory infections during the 5 years before enrollment (P < .01). Participants with cardiovascular malformations requiring surgery or with anatomic spleen abnormalities showed lower median BMI z scores and more hospitalizations and IV therapies for respiratory illnesses compared with participants without SA. INTERPRETATION: Children with PCD and SA achieve worse nutritional and pulmonary outcomes with more hospitalizations for acute respiratory illnesses than those with SS or SIT combined. Poor nutrition and increased hospitalizations for respiratory infections in participants with SA and PCD are associated with cardiovascular malformations requiring cardiac surgery, splenic anomalies, or both. TRIAL REGISTRY: ClinicalTrials.gov; Nos.: NCT02389049 and NCT00323167; URL: www. CLINICALTRIALS: gov.

Cobalt(I)-Catalyzed (3 + 2 + 2) Cycloaddition between Alkylidenecyclopropanes, Alkynes, and Alkenes.

Cobalt(I) catalysts equipped with bisphosphine ligands can be used to promote formal (3 + 2 + 2) intramolecular cycloadditions of enynylidenecyclopropanes of type 1. The method provides synthetically appealing 5,7,5-fused tricyclic systems in good yields and with complete diastereo- and chemoselectivity. Interestingly, its scope differs from that of previously reported annulations based on precious metal catalysts, specifically rhodium and palladium. Noticeably, density functional theory calculations confirm that the mechanism of the reaction is also different from those proposed for these other catalysts.

Persistently elevated alkaline phosphatase without hepatopathy?: literature review.

Elevated alkaline phosphatase (ALP) levels are found in multiple hepatobiliary diseases and in bone diseases. ALP can also originate in the intestine and placenta. Very few cases of persistent elevations of IALP or in the context of benign familial intestinal hyperphosphatasemia (BFIH) without underlying pathology have been reported in the literature. In the evaluation of elevated ALP, most patients will not require determination of its isoenzymes. However, it is important to be aware of this entity to avoid unnecessary additional studies and to establish the diagnosis of a persistent but benign biochemical abnormality.

Azithromycin promotes proliferation, and inhibits inflammation in nasal epithelial cells in primary ciliary dyskinesia.

Primary ciliary dyskinesia (PCD) is a genetic disorder associated with recurrent and chronic respiratory infections due to functional defects of motile cilia. In this study, we aimed to elucidate inflammatory and proliferative responses in PCD respiratory epithelium and evaluate the effect of Azithromycin (AZT) on these responses. Airway basal cells (BCs) were isolated from nasal samples of Wild-type (WT) epitope of healthy donors and PCD donors with bi-allelic mutations in DNAH5, DNAH11 and CCDC39. Cells were expanded in vitro and stimulated with either Lipopolysaccharide (LPS) or vehicle control. Post stimulation, cells were treated with either Azithromycin (AZT) or vehicle control. Cell proliferation was imaged in real-time. Separately, BCs from the same donors were expanded and grown at an air-liquid interface (ALI) to generate a multi-ciliated epithelium (MCE). Once fully mature, cells were stimulated with LPS, AZT, LPS + AZT or vehicle control. Inflammatory profiling was performed on collected media by cytokine Luminex assay. At baseline, there was a significantly higher mean production of pro-inflammatory cytokines by CCDC39 BCs and MCEs when compared to WT, DNAH11 and DNAH5 cells. AZT inhibited production of cytokines induced by LPS in PCD cells. Differences in cell proliferation were noted in PCD and this was also corrected with AZT treatment.

Straightforward Synthesis of Bis[(trifluoromethyl)sulfonyl]ethylated Isocoumarins from 2-Ethynylbenzoates.

Herein, we report a facile isocoumarin and isoquinolone preparation by taking advantage of an initial bis(triflyl)ethylation [triflyl = (trifluoromethyl)sulfonyl] reaction, followed by heterocyclization, which contrasts with our previous results on cyclobutene formation. The efficiency of the catalyst- and irradiation-free heterocyclization/bis(triflyl)ethylation sequence showed exquisite dependence on the electronic nature of the substituents at the 2-ethynylbenzoate(benzamide) precursors. Molecular docking of model bis(triflyl)ethylated isocoumarins on human acetylcholinesterase (hAChE) revealed promising biological activities through selective coordination on both the catalytic active site and peripheral active site.

Notch signaling inactivation by small molecule γ-secretase inhibitors restores the multiciliated cell population in the airway epithelium.

Multiciliated cell loss is a hallmark of airway epithelial remodeling in chronic inflammatory airway diseases including cystic fibrosis (CF), asthma, and chronic obstructive pulmonary disease. It disrupts mucociliary clearance, which fuels disease progression. Effective clearance requires an optimal proportion of multiciliated and secretory cells. This is controlled by Notch signaling such that between two adjacent cells the one that activates Notch becomes a secretory cell and the one that avoids Notch activation becomes a multiciliated cell. Consequently, blocking Notch by a small molecule inhibitor of the γ-secretase enzyme that cleaves the Notch receptor for signal activation directs differentiation toward the multiciliated lineage. Thus, γ-secretase inhibitor (GSI) treatment may alleviate multiciliated cell loss in lung disease. Here, we demonstrate the therapeutic restoration of multiciliated cells by the GSI LY450139 (semagacestat). LY450139 increased multiciliated cell numbers in a dose-dependent manner in healthy primary human nasal epithelial cells (HNECs) during differentiation and in mature cultures, but not when applied during early epithelialization of progenitors. LY450139 did not impact stem cell proliferation. Basal and apical administration were equally effective. In healthy adult mice, LY450139 increased multiciliated cell numbers without detectible toxicity. LY450139 also increased multiciliated cells and decreased excess mucus secretory cells in CF HNECs and IL-13 remodeled healthy HNECs. LY450139 normalized multiciliated cell numbers in CF HNECs without interfering with the activity of CFTR modulator compounds. In summary, we demonstrate that GSI administration is a promising therapeutic to restore multiciliated cells and potentially improve epithelial function in a wide range of chronic lung diseases.NEW & NOTEWORTHY Our findings show that low-dose, short-term topical or systemic γ-secretase inhibitor treatment may lead to restoration of multiciliated cells without toxicity and potentially improve epithelial function in a wide range of chronic lung diseases.

The Danish-American Research Exchange (DARE): a cross-sectional study of a binational research education program.

BACKGROUND: Most medical educational programs emphasize clinical observation or clinical skill acquisition, fewer focus upon research. The Danish-American Research Exchange (DARE) program, sponsored by the Lundbeck Foundation, is unique in that the medical student initiates biomedical research collaboration between Danish and US medical institutions. To achieve this, Danish medical students (DARE students) conduct binational mentored research projects while based in the United States for 10 months. In addition, DARE students are introduced to interdisciplinary thinking about how to develop ultra-low-cost healthcare interventions through the '$10 Challenge'. METHODS: We conducted a cross-sectional study of DARE alumni over five consecutive years (2015-2020, n = 24). Research metrics included completion of a research project, primary authorship, and co-authorship of publications. The number of publications, prior to and after the DARE program were enumerated. For the first four cohorts, graduation from medical school and acceptance or intention to enter a joint MD-PhD program also were assessed. Two focus groups were conducted using constructivist grounded theory. Discussions were transcribed, redacted, and coded using Dedoose software. RESULTS: DARE Medical students were 31.2 years (range 24-35), the majority were women (67%;16/24). The majority (17/24;71%) completed a first author publication in a peer-reviewed journal with a median of 3.9 per DARE alumnus. DARE alumnus reported increased proficiency in biostatistics, epidemiology, coding and public speaking as well as stronger research qualities in creativity, critical thinking, comfort in approaching scientist in both the US and Denmark (p < 0.001 for all). Qualitative key themes included: increased confidence, a deepening of research inquiry and linkage to a research network. CONCLUSIONS: Preliminarily, this study suggests that medical students can initiate binational collaboration in medicine. Benefits include research productivity, intention to pursue academic medical careers, as well as positive impacts on motivation. This medical student-initiated research model lays the groundwork for using this model across other country pairs to promote binational collaboration.

Endoscopic management of an iatrogenic duodenal perforation and choledocholithiasis in the same endoscopic retrograde cholangiopancreatography session.

We present the case of a 67-year-old female with recent cholecystectomy for symptomatic cholelithiasis. She was admitted to our hospital with right upper quadrant abdominal pain and vomiting. Laboratory analysis revealed hyperbilirubinemia with cytolysis and cholestasis. Abdominal ultrasound revealed a choledocholithiasis of 8 mm. Endoscopic retrograde cholangiopancreatography (ERCP) was scheduled. With the duodenoscope, after the reduction maneuver from the second duodenal portion to face the major papilla, a perforation of approximately 18 mm was identified in the contralateral wall distal to it. A gastroscope identified the perforation and a 9.5-11 x 6 mm over-the-scope-clip (OTSC) was placed after inserting its edges into the cap with aspiration (without approximation forceps).

Airway Disease in Children with Primary Ciliary Dyskinesia: Impact of Ciliary Ultrastructure Defect and Genotype.

Rationale: Primary ciliary dyskinesia (PCD) is characterized by impaired mucociliary clearance, recurrent respiratory infections, progressive airway damage, and obstructive lung disease. Although the association of ciliary ultrastructure defect/genotype with the severity of airflow obstruction has been well characterized, their association with airway abnormalities on chest computed tomography (CT) has been minimally evaluated. Objectives: We sought to delineate the association of ciliary defect class/genotype with chest CT scores in children with PCD. Methods: Cross-sectional analysis of children with PCD (N = 146) enrolled in a prospective multicenter observational study, stratified by defect type: outer dynein arm (ODA), ODA/inner dynein arm (IDA), IDA/microtubular disorganization (MTD), and normal/near normal ultrastructure with associated genotypes. CTs were scored using the MERAGMA-PCD (Melbourne-Rotterdam Annotated Grid Morphometric Analysis for PCD), evaluating airway abnormalities in a hierarchical order: atelectasis, bronchiectasis, bronchial wall thickening, and mucus plugging/tree-in-bud opacities. The volume fraction of each component was expressed as the percentage of total lung volume. The percentage of disease was computed as the sum of all components. Regression analyses were used to describe the association between clinical predictors and CT scores. Results: Acceptable chest CTs were obtained in 141 children (71 male): 57 ODA, 20 ODA/IDA, 40 IDA/MTD, and 24 normal/near normal. The mean (standard deviation) age was 8.5 (4.6) years, forced expiratory volume in 1 second (FEV1) percent predicted was 82.4 (19.5), and %Disease was 4.6 (3.5). Children with IDA/MTD defects had a higher %Disease compared with children with ODA defects (2.71% higher [95% confidence interval (CI), 1.37-4.06; P < 0.001]), driven by higher %Mucus plugging (2.35% higher [1.43-3.26; P < 0.001]). Increasing age, lower body mass index, and lower FEV1 were associated with a higher %Disease (0.23%; 95% CI, 0.11-0.35; P < 0.001 and 0.03%; 95% CI, 0.01-0.04; P = 0.008 and 0.05%; 95% CI, 0.01-0.08; P = 0.011, respectively). Conclusions: Children with IDA/MTD defects had significantly greater airway disease on CT, primarily mucus plugging, compared with children with ODA defects.

SARS-CoV-2 replication in airway epithelia requires motile cilia and microvillar reprogramming.

How SARS-CoV-2 penetrates the airway barrier of mucus and periciliary mucins to infect nasal epithelium remains unclear. Using primary nasal epithelial organoid cultures, we found that the virus attaches to motile cilia via the ACE2 receptor. SARS-CoV-2 traverses the mucus layer, using motile cilia as tracks to access the cell body. Depleting cilia blocks infection for SARS-CoV-2 and other respiratory viruses. SARS-CoV-2 progeny attach to airway microvilli 24 h post-infection and trigger formation of apically extended and highly branched microvilli that organize viral egress from the microvilli back into the mucus layer, supporting a model of virus dispersion throughout airway tissue via mucociliary transport. Phosphoproteomics and kinase inhibition reveal that microvillar remodeling is regulated by p21-activated kinases (PAK). Importantly, Omicron variants bind with higher affinity to motile cilia and show accelerated viral entry. Our work suggests that motile cilia, microvilli, and mucociliary-dependent mucus flow are critical for efficient virus replication in nasal epithelia.