Treatment Discontinuation Patterns for Patients With Chronic Lymphocytic Leukemia in Real-World Settings: Results From a Multi-Center International Study

Introduction: This study assessed treatment discontinuation patterns and reasons among chronic lymphocytic leukemia (CLL) patients initiating first-line (1L) and second-line (2L) treatments in real-world settings. Materials and / Methods: Using deidentified electronic medical records from the CLL Collaborative Study of Real-World Evidence, premature treatment discontinuation was assessed among FCR, BR, BTKi-based, and BCL-2-based regimen cohorts. / Results: Of 1364 1L patients (initiated in 1997-2021), 190/13.9% received FCR (23.7% discontinued prematurely); 255/18.7% received BR (34.5% discontinued prematurely); 473/34.7% received BTKi-based regimens, of whom 28.1% discontinued prematurely; and 43/3.2% received venetoclax-based regimens, of whom 16.3% discontinued prematurely (venetoclax monotherapy: 7/0.5%, of whom 42.9% discontinued; VG/VR: 36/2.6%, of whom 11.1% discontinued). The most common reasons for treatment discontinuation were adverse events (FCR: 25/13.2%; BR: 36/14.1%; BTKi-based regimens: 75/15.9%) and disease progression (venetoclax-based: 3/7.0%). Of 626 2L patients, 20/3.2% received FCR (50.0% discontinued); 62/9.9% received BR (35.5% discontinued); 303/48.4% received BTKi-based regimens, of whom 38.0% discontinued; and 73/11.7% received venetoclax-based regimens, of whom 30.1% discontinued (venetoclax monotherapy: 27/4.3%, of whom 29.6% discontinued; VG/VR: 43/6.9%, of whom 27.9% discontinued). The most common reasons for treatment discontinuation were adverse events (FCR: 6/30.0%; BR: 11/17.7%; BTKi-based regimens: 60/19.8%; venetoclax-based: 6/8.2%). / Conclusion: The findings of this study highlight the continued need for tolerable therapies in CLL, with finite therapy offering a better tolerated option for patients who are newly diagnosed or relapsed/refractory to prior treatments

Calcium Signals Driven by Single Channel Noise

Usually, the occurrence of random cell behavior is appointed to small copy numbers of molecules involved in the stochastic process. Recently, we demonstrated for a variety of cell types that intracellular Ca2+ oscillations are sequences of random spikes despite the involvement of many molecules in spike generation. This randomness arises from the stochastic state transitions of individual Ca2+ release channels and does not average out due to the existence of steep concentration gradients. The system is hierarchical due to the structural levels channel - channel cluster - cell and a corresponding strength of coupling. Concentration gradients introduce microdomains which couple channels of a cluster strongly. But they couple clusters only weakly; too weak to establish deterministic behavior on cell level. Here, we present a multi-scale modelling concept for stochastic hierarchical systems. It simulates active molecules individually as Markov chains and their coupling by deterministic diffusion. Thus, we are able to follow the consequences of random single molecule state changes up to the signal on cell level. To demonstrate the potential of the method, we simulate a variety of experiments. Comparisons of simulated and experimental data of spontaneous oscillations in astrocytes emphasize the role of spatial concentration gradients in Ca2+ signalling. Analysis of extensive simulations indicates that frequency encoding described by the relation between average and standard deviation of interspike intervals is surprisingly robust. This robustness is a property of the random spiking mechanism and not a result of control

G protein-coupled receptor-mediated calcium signaling in astrocytes

Astrocytes express a large variety of G~protein-coupled receptors (GPCRs) which mediate the transduction of extracellular signals into intracellular calcium responses. This transduction is provided by a complex network of biochemical reactions which mobilizes a wealth of possible calcium-mobilizing second messenger molecules. Inositol 1,4,5-trisphosphate is probably the best known of these molecules whose enzymes for its production and degradation are nonetheless calcium-dependent. We present a biophysical modeling approach based on the assumption of Michaelis-Menten enzyme kinetics, to effectively describe GPCR-mediated astrocytic calcium signals. Our model is then used to study different mechanisms at play in stimulus encoding by shape and frequency of calcium oscillations in astrocytes.Comment: 35 pages, 6 figures, 1 table, 3 appendices (book chapter

Astrocyte networks and intercellular calcium propagation

International audienceAstrocytes organize in complex networks through connections by gap junction channels that are regulated by extra-and intracellular signals. Calcium signals generated in individual cells, can propagate across these networks in the form of intercellular calcium waves, mediated by diffusion of second messengers molecules such as inositol 1,4,5-trisphosphate. The mechanisms underpinning the large variety of spatiotemporal patterns of propagation of astrocytic calcium waves however remain a matter of investigation. In the last decade, awareness has grown on the morphological diversity of astrocytes as well as their connections in networks, which seem dependent on the brain area, developmental stage, and the ultra-structure of the associated neuropile. It is speculated that this diversity underpins an equal functional variety but the current experimental techniques are limited in supporting this hypothesis because they do not allow to resolve the exact connectivity of astrocyte networks in the brain. With this aim we present a general framework to model intercellular calcium wave propagation in astrocyte networks and use it to specifically investigate how different network topologies could influence shape, frequency and propagation of these waves

Eustachian tube dysfunction in children after surgical interventions into the nasopharynx

The diagnosis and correction of tube disorders remain one of the least resolved and the most difficult problem in otorhinolaryngology. Eustachian tube function was evaluated in 144 children with recurrent otitis media and exudative otitis media after surgical intervention into the nasopharynx. All the children underwent tympanometry and diagnostic endoscopy of the nasal cavity and nasopharynx. Before surgery, types B, C, and A tympanograms were recorded in 146 (50.69%), 97 (33.68%), and 45 (15.62%) cases, respectively. key. One month after surgery, tympanometry readings became normal in 85 (91.39%) children.Conclusion. The most complete diagnostic information can be obtained during different endoscopic modes in children with tube dysfunctions. Tympanometry is an objective noninvasive method for the assessment of Eustachian tube function and a criterion for the evaluation of the efficiency of the treatment performed

EXTRAOESOPHAGEAL MANIFESTATIONS OF GASTROESOPHAGEAL REFLUX DISEASE IN THE PRACTICE OF PEDIATRIC OTORHINOLARYNGOLOGIST

Gastroesophageal reflux disease (GERD) is a chronic recurrent disorder with esophageal and extraesophageal symptoms and a variety of morphological changes of the mucous membrane of the esophagus caused by retrograde reflux of the gastric or gastro-intestinal contents. Extraesophageal (atypical) symptoms are mainly complaints which indicate involvement in the process of bronchopulmonary, cardiovascular diseases and ENT-organs. This article discusses the pathogenesis of extraesophageal manifestations of GERD, and recommendations on diagnosis and treatment based on the author’s own experience and data of international publications

Dry eye disease ranking among common reasons for seeking eye care in a large US claims database

John L Bradley,1,2 Ipek Özer Stillman,3 Irina Pivneva,4 Annie Guerin,4 Amber M Evans,5 Reza Dana6 1Naval Medical Research Unit Dayton, Vision Science Lab, Wright Patterson AFB, OH, USA; 2University of Pikeville, Kentucky College of Optometry, Pikeville, KY, USA; 3Takeda, Lexington, MA, USA; 4Analysis Group, Inc, Montreal, QC, Canada; 5Health ResearchTx LLC, Trevose, PA, USA; 6Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, MA, USA Objectives: Dry eye disease (DED) is a complex multifactorial condition of the ocular surface characterized by symptoms of ocular discomfort, irritation, and visual disturbance. Data previously reported from this study showed an increase in prevalence and incidence of DED with age and over time. The objective of this study was to compare the ranking of DED prevalence among other ocular conditions that led patients to seek eye care. Methods: In this population-based study using the US Department of Defense Military Health System claims database of >9.7 million beneficiaries, indicators of DED and other ocular conditions were analyzed over time. The overall prevalence (2003–2015) and annual incidence (2008–2012) of DED and other ocular conditions were estimated using an algorithm based on two independent indicators derived from selected diagnostic and procedure codes and prescriptions for cyclosporine ophthalmic emulsion for DED and diagnostic codes for the indicators of other common ocular conditions. Results: In 2003–2015, the most common ocular conditions were disorders of refraction and accommodation (25.84%), cataracts (17.14%), glaucoma (7.27%), disorders of the conjunctiva (6.76%), other retinal disorders (5.94%), and DED (5.28%). DED was the fifth most prevalent ocular condition in women (7.78%) and ninth most prevalent in men (2.96%). In 2012, DED had the third highest annual incidence (0.87%), behind disorders of refraction/accommodation (1.87%) and cataracts (1.50%). Conclusion: This study provided further epidemiologic evidence for DED as a commonly occurring condition that drives patients to seek treatment. Keywords: DED, epidemiology, prevalence, incidenc

Mitochondria adjust Ca(2+) signaling regime to a pattern of stimulation in salivary acinar cells

AbstractThe salivary acinar cells have unique Ca2+ signaling machinery that ensures an extensive secretion. The agonist-induced secretion is governed by Ca2+ signals originated from the endoplasmic reticulum (ER) followed by a store-operated Ca2+ entry (SOCE). During tasting and chewing food a frequency of parasympathetic stimulation increases up to ten fold, entailing cells to adapt its Ca2+ machinery to promote ER refilling and ensure sustained SOCE by yet unknown mechanism. By employing a combination of fluorescent Ca2+ imaging in the cytoplasm and inside cellular organelles (ER and mitochondria) we described the role of mitochondria in adjustment of Ca2+ signaling regime and ER refilling according to a pattern of agonist stimulation. Under the sustained stimulation, SOCE is increased proportionally to the degree of ER depletion. Cell adapts its Ca2+ handling system directing more Ca2+ into mitochondria via microdomains of high [Ca2+] providing positive feedback on SOCE while intra-mitochondrial tunneling provides adequate ER refilling. In the absence of an agonist, the bulk of ER refilling occurs through Ca2+-ATPase-mediated Ca2+ uptake within subplasmalemmal space. In conclusion, mitochondria play a key role in the maintenance of sustained SOCE and adequate ER refilling by regulating Ca2+ fluxes within the cell that may represent an intrinsic adaptation mechanism to ensure a long-lasting secretion