Search Results (128)

Voltage-gated potassium channels (Kv) are a large family of potassium channels composed of 40 members across 12 subtypes. The KCNH genes encode three subfamilies of voltage-gated potassium channels: Kv10 (EAG, ether à go go), Kv11 (ERG, EAG-related gene), and Kv12 (ELK, EAG-like K). Kv channels play prominent roles in neuronal and cardiovascular systems. Mutations in Kv channels have been linked to many human diseases, such as epilepsy, heart arrhythmias, and cancers. Significant progress has been made in understanding protein structures, physiological functions, and pharmacological modifiers. However, the evolutionary history and gene expression of vertebrate KCNH genes during embryonic development remain largely unknown. We systematically identified and cloned 14 kcnh genes in zebrafish. Then, we examined the vertebrate KCNH channel evolution by phylogenetic and syntenic analyses. Our data reveal that the three subtypes of the KCNH gene family had already evolved in invertebrates, long before the emergence of vertebrates. The number of vertebrate KCNH genes increased, most likely due to whole-genome duplications (WGDs). In addition, we examined zebrafish kcnh gene expression during early embryogenesis by in situ hybridization. Each subgroup’s genes showed similar but distinct gene expression domains with some exceptions. Most of them were expressed in neural tissues. Notably, kcnh6a showed robust expression in the developing heart, consistent with its conserved role in cardiac repolarization. Additionally, a few kcnh genes were transiently expressed in non-neural tissues, such as somites and the notochord, suggesting they may have a unique role in embryonic development. Our phylogenetic and developmental analyses of KCNH channels shed light on their evolutionary history and potential roles during embryogenesis, in line with their physiological functions and human channelopathies. Full article

Purpose: To describe the long-term, multimodal follow-up and multidisciplinary evaluation of two pediatric patients with CDH3-related retinopathy, discussing the genotypic and phenotypic spectrum of this rare cadherinopathy. Design: Retrospective observational case series. Methods: Two unrelated children with early-onset macular dystrophy and congenital hypotrichosis underwent a comprehensive ophthalmic examination, including spectral-domain optical coherence tomography (SD-OCT), blue-light fundus autofluorescence (BAF), microperimetry, and full-field electroretinography (ffERG), combined with dermatologic assessment and exome sequencing. Follow-up extended over 4 years in Patient 1 and 15 years in Patient 2. Results: Both patients showed sharply demarcated posterior pole chorioretinal atrophy with preservation of the peripheral retina and stable best-corrected visual acuity throughout follow-up. Microperimetry documented localized sensitivity loss with limited progression. SD-OCT revealed persistent ellipsoid zone disruption, retinal pigment epithelium atrophy, and outer retinal tubulations. Dermatologic evaluation confirmed congenital hypotrichosis without nail abnormalities; one patient exhibited mild fifth finger clinodactyly. Genetic testing identified the following two distinct homozygous CDH3 variants: a splice-site mutation (c.160+1G>A) and a frameshift insertion (c.1837dup, p.(Asp613Glyfs*4)). Conclusions:CDH3 retinopathy presents with a characteristic multimodal imaging pattern of localized macular atrophy and slow functional decline associated with congenital hypotrichosis. A comprehensive multidisciplinary approach was essential for the correct diagnosis and a better and more thorough definition of the clinical presentation. Detailed long-term follow-up supports the hypothesis of retinal pigment epithelium dysfunction or maldevelopment rather than widespread retinal degeneration. Recognition of this phenotype is critical for accurate diagnosis, genetic counseling, and future gene-therapy strategies targeting the preserved peripheral retina. Full article

Candidozyma auris (formerly known as Candida auris) has emerged as a formidable clinical fungal pathogen as a result of its multidrug resistance and persistent colonization capabilities. In this study, three clinical C. auris strains (namely C. auris strain 01, C. auris strain 03, and C. auris strain 13) with distinct origins were characterized to investigate their phenotypic variations and mechanisms of azole resistance. Comprehensive profiling revealed significant inter-strain differences in biofilm formation, cell surface hydrophobicity, adhesion capacity, and phospholipase activity. Testing for antifungal susceptibility showed that the three clinical strains exhibited different minimum inhibitory concentrations for multiple azoles (fluconazole, voriconazole, and itraconazole) and echinocandins (anidulafungin and micafungin). Sequencing identified Y132F mutations in the ERG11 gene of the three clinical strains. Mechanistic investigations demonstrated that fluconazole exposure significantly upregulated the expression of efflux pump genes (CDR1 and CDR2) and the genes encoding their transcriptional regulators (MDR1 and TAC1b). In a murine skin colonization model, comparing data from the standard strain C. auris strain CBS12766 and clinical strains of C. auris strain 03 and C. auris strain 13 exhibited a significantly higher fungal burden of tissue, whereas strain C. auris strain 01 showed an intermediate level. Host immunity response analysis revealed that expression of the IL-1β gene was significantly elevated in C. auris strain CBS12766-infected mice, while expression of IL-6 and CXCL-1 genes was predominantly increased in the C. auris strain 01, with TNF-α gene expression levels being comparable across all strains. Histopathological examination confirmed local infiltration of inflammatory cells and mild epidermal edema, indicating active host immune engagement. Overall, our findings highlighted substantial phenotypic heterogeneity, different colonization capacities, and differences in expression of inflammatory cytokines among the C. auris strains. Further investigations into fluconazole-response mechanisms identified enhanced efflux pump activity, along with ERG11 gene Y132F mutations and transcription factor modulation among these clinical strains. Full article

Background/Objectives: Poly (ADP-ribose) polymerase (PARP1) has emerged as a promising therapeutic target in human breast cancer particularly in BRCA1/2 mutation carriers where a synthetic lethal interaction leads to massive tumor cell death upon specific inhibitors’ administration. Current clinically approved PARP inhibitors (Talazoparib and Olaparib) show outstanding therapeutic capabilities but suffer from severe side effects. Most importantly, some of them can cause life-threatening cardiotoxicity through hERG off-target effects. Here, we performed an extensive study to identify lead compounds with improved binding modes and favorable predicted pharmacokinetics using an integrated computational strategy. Methods: An artificial intelligence-driven drug design (AIDDISON™ v2023) workflow was employed to search ultra-large chemical space libraries for active compounds, which were then optimized via computer-aided methods to form a PARP-Tailored Database (PTD). This database was then analyzed through a virtual screening workflow, molecular docking studies, molecular dynamics (MD) simulations, MM/GBSA binding free energy calculations, DFT analysis and ADME/Tox predictions using the Schrödinger suite (v2023-2), MobaXterm v25.2, Gaussian 16.0, ProTox-3 and Pred-hERG v5.0 respectively. Results: Three compounds (1a–1c) were identified as promising candidates. Among them 1a appeared to be the most active compound with a favorable docking score (−9.488 kcal/mol) that is not only higher than 1b and 1c but also higher than that of Talazoparib (−6.778 kcal/mol). MD simulations of 1a–1c in the active site revealed an average RMSD of ~2.5–3.6 Å which is better compared to the parent Talazoparib (5.6 Å). Interestingly, on the 250 ns extended MD study, 1a exhibited a slightly reduced RMSD between 2.4 and 3.2 Å, whereas Talazoparib retained higher fluctuations of ~5 Å to 6 Å. MM/GBSA binding energy analysis indicated 1a to have better predicted binding affinity (−67.820 kcal/mol), which is also better than Talazoparib (−63.734 kcal/mol). DFT calculations showed good electronic properties and in silico ADMET studies also indicated 1a to have good drug-likeness and lower predicted hepatotoxicity and cardiotoxicity risk. Conclusions: These findings identify compound 1a as a promising lead, while compounds 1b and 1c remain viable candidates for further optimization. However, experimental validation is critical to confirm the predicted biological activity and safety profiles. Full article

Kv11.1 (hERG1) channels, encoded by KCNH2, mediate the rapid delayed rectifier potassium current (I_Kr) crucial for cardiac repolarization. Disruptions, via mutations or antiarrhythmic drugs like dofetilide cause severe arrhythmogenic disorders, including Long QT Syndrome Type 2 (LQT2), Brugada Syndrome (BrS), and Torsades de Pointes (TdP). While Kv11.1’s role in channelopathies and drug-induced arrhythmias is established, understanding its complex regulation and therapeutic targeting remains a challenge. This review synthesizes the structural, functional, and regulatory aspects of Kv11.1 channels and their clinical implications. Recent studies using iPSC-derived cardiomyocytes highlight regulation by PI3K/Akt, PKC, and PKA signaling via phosphorylation (Ser283, Ser890) and interactions with proteins like 14-3-3. Beyond electrophysiology, Kv11.1 influences pathological hypertrophy and non-cardiac functions including insulin secretion. Pharmacological efforts focus on activators to shorten action potential duration and suppress TdP, and blockers with overdose risks. Mutation heterogeneity, exemplified by trafficking impairment (G785D) in LQT2 and gain-of-function (R397C) in BrS, complicates precision therapy. Clinically, systematic risk stratification using electrocardiographic parameters and genotype-specific approaches enables personalized management. Beta-blockers remain first-line therapy for LQTS2, while rigorous avoidance of QT-prolonging medications and electrolyte monitoring form the cornerstones of preventive care. Advancing Kv11.1-targeted therapies with approaches like CRISPR-Cas9 and pharmacological chaperones (e.g., lumacaftor) holds promise for personalized treatments, ultimately reducing arrhythmic events and sudden cardiac death. Full article

Background/Objectives: Puerto Rican Hispanic/Latino (PR H/L) men experience a heightened incidence and mortality rate of aggressive forms of prostate cancer. The underlying causes of this increased disease burden likely include a complex interplay of socio-economic and biological factors. This pilot study leveraged the first cancer tissue biobank at a Hispanic-Serving Institution (Puerto Rico BioBank) and aimed to provide an initial description of the genomic features of prostate cancer in 35 PR H/L men. Methods: Whole-exome and RNA sequencing were performed on prostate adenocarcinoma tumor samples to investigate the genomic features associated with prostate cancer. Results: Our analysis suggests that mutation profiles and gene expression pattern differences are observed in this population and may be associated with disease aggressiveness and progression. Notably, mutations in TP53 and TMPRSS2-ERG gene fusions, which are common in broader populations, were less prevalent in the PR H/L cohort. Conclusions: While this study contributes to the understanding of ethnicity-specific genetic factors in prostate cancer, underscoring the need for inclusive genomic studies, continued expansion to larger cohorts of patients under-represented in large genomic studies will be needed to more robustly characterize the full range of genomic features of prostate cancer. A broader understanding of the genomic features of prostate cancer in PR H/L men may lead to future opportunities for delivering more personalized prognoses and treatment options, helping to ensure that treatment advances and better outcomes are available to all patients. Full article

Invasive fungal diseases (IFDs) represent an escalating global health threat, compounded by the rapid emergence of antifungal resistance (AFR). This review synthesizes the contemporary landscape of AFR from clinical and microbiological perspectives, providing actionable insights for clinical practitioners. We examine the epidemiology of critical pathogens, including Candidozyma auris, clonal Candida parapsilosis, azole-resistant Aspergillus fumigatus, and dissect the underlying molecular mechanisms, from genetic mutations in ERG11 and cyp51A to novel emerging epigenetic and adaptive strategies. We critically appraise the diagnostic gap between phenotypic testing and clinical urgency, highlighting the role of rapid molecular assays and next-generation sequencing. Finally, we evaluate evidence-based therapeutic strategies, including the integration of novel agents such as rezafungin, ibrexafungerp, olorofim, and fosmanogepix), while emphasizing the imperative of antifungal stewardship, infection prevention and control in mitigating resistance, and “One-Health” interventions. Full article

Milk beer, a modern Chinese dairy beverage, is usually fermented by the co-culture of lactic acid bacteria (LAB) and Kluyveromyces marxianus (K. marxianus), with the latter known for its ability to produce aroma compounds. However, the accumulation of lactic acid produced by LAB can inhibit the growth of K. marxianus, which inevitably hinders the diversity and intensity of flavor compounds in milk beer. In this study, adaptive laboratory evolution (ALE) was applied to the parental strain Kluyveromyces marxianus CICC1953 (Km-P) under different concentrations of lactic acid to obtain an evolved strain Km-ALE-X20 with enhanced acid tolerance and increased titer of phenylethyl alcohol, which has a floral, rose-like aroma. Km-ALE-X20 demonstrated a 16-fold increase in OD₆₀₀ and a 28-fold increase in phenylethyl alcohol production compared with Km-P in chemically defined medium (CDM) containing 20 g/L lactic acid. Comparative genomics analysis suggested that mutated genes CTA1, TSL1, ERG2 were related to enhanced acid tolerance, while ARO8, ARO9, FKS2 were related to increased production of aroma compounds. Furthermore, Km-ALE-X20-fermented milk beer showed 33.87% and 32.43% higher production in alcohol and ester compounds than that of Km-P-fermented milk beer. Interestingly, sensory analysis showed that while Km-ALE-X20-fermented milk beer had higher sensory scores for rose and fruity aroma attributes, Km-P-fermented milk beer possessed a more balanced aroma profile. This paper highlights the first application of ALE to enhance the signature rose aroma of K. marxianus-fermented milk beer and provides an efficient framework for ALE-based breeding of aroma-producing food microorganisms. Full article

Background/Objectives: Herein, we report the clinical cases of two affected first-degree relatives from a family with highly variable macular dystrophy, expanding the known phenotype spectrum with mutations in the thyroid hormone receptor beta gene (THRB). Methods: Multimodal retinal imaging included wide-field fundus photography, fundus autofluorescence (FAF), spectral domain optical coherence tomography (SD-OCT) imaging, performed alongside functional testing (visual fields, electroretinogram (ERG)), metabolic blood analyses, and genetic testing of both cases. Results: A 67-year-old female patient presenting with reading difficulties and visual impairment since childhood was referred for evaluation and counseling for potential treatment options. Extensive ophthalmologic examination, including multimodal retinal imaging and functional testing, revealed an occult macular dystrophy. Her 39-year-old son reported similar visual symptoms in combination with mild photophobia. In multimodal retinal imaging, he also showed a macular dystrophy but with a vitelliform phenotype. Genetic testing identified the heterozygous pathogenic variant c.283+1G>A in the thyroid hormone receptor beta gene (THRB) in both patients. Conclusions: This report shows a high intrafamilial variability of macular dystrophy caused by a heterozygous THRB mutation, which has only recently been recognized as a cause of macular dystrophy. Here, we describe a novel clinical presentation characterized by a vitelliform lesion, expanding the phenotypic spectrum of THRB-associated macular dystrophy. Full article

Prostate cancer (PC) has long been considered a disease of older men. Still, a significant and concerning rise in diagnoses among younger men has revealed a biologically distinct and more aggressive clinical entity: early-onset prostate cancer (EO-PC). This comprehensive review synthesizes the molecular and clinical evidence to demonstrate that PC is not a single disease, but a collection of distinct entities delineated by patient age. EO-PC is characterized by a strong genetic component, unique fusion events like TMPRSS2-ERG, and a highly plastic phenotype driven by intense Notch signaling and a hybrid epithelial-to-mesenchymal transition. In stark contrast, late-onset prostate cancer (LO-PC) is defined by a higher mutational burden, an epigenetic “field defect” that accumulates with age, and a predominantly immunosuppressive tumor microenvironment. These profound biological differences have significant implications for diagnosis, prognosis, and therapeutic strategies. Traditional prognostic tools, such as the Gleason score, are often insufficient to capture the full spectrum of risk in younger men. The divergent molecular landscapes of EO-PC and LO-PC necessitate a fundamental shift from a standard approach to an age-aware precision medicine framework. This review highlights key therapeutic targets and underscores the critical need for a new paradigm in PC management to improve patient outcomes. Full article

Candida auris has emerged as a global public health threat due to its high mortality rates, multidrug resistance, and rapid transmission in healthcare settings. This study reports the first documented cases of C. auris candidemia in Portugal, comprising eight isolates from candidemia and colonised patients admitted to a major hospital in northern Portugal in 2023. Whole-genome sequencing (WGS) was performed to determine the phylogenetic relationships of the isolates, which were classified as belonging to Clade I. Genome sequencing also enabled the detection of missense mutations in antifungal resistance genes, which were correlated with antifungal susceptibility profiles determined according to EUCAST (European Committee on Antimicrobial Susceptibility Test) protocols and guidelines. All isolates exhibited resistance to fluconazole and amphotericin B according to the recently established EUCAST epidemiological cut-offs (ECOFFs). Most of the isolates showed a resistant phenotype to anidulafungin and micafungin. All isolates were resistant to caspofungin. Missense mutations identified included Y132F in ERG11, E709D in CDR1, A583S in TAC1b, K52N and E1464K in SNQ2, K74E in CIS2, M192I in ERG4, a novel mutation S237T in CRZ1, and variants in GCN5, a gene involved in chromatin remodelling and stress-response regulation. Identifying known and novel mutations highlights the evolution of antifungal resistance mechanisms in C. auris. These findings underscore the need for further research to understand C. auris resistance pathways and to guide effective clinical management strategies. Full article

Trichophyton indotineae is an emerging dermatophyte species responsible for recalcitrant and terbinafine-resistant dermatophytosis, raising concerns over diagnostic accuracy and treatment efficacy. This study aimed to improve the identification and resistance profiling of T. indotineae by integrating molecular methods with machine learning-assisted analysis of MALDI-TOF mass spectra. A total of 56 clinical isolates within the Trichophyton mentagrophytes complex were analyzed using ITS and ERG1 gene sequencing, antifungal susceptibility testing, and MALDI-TOF MS profiling. Terbinafine resistance was detected in 23 isolates and correlated with specific ERG1 mutations, including F397L, L393S, F415C, and A448T. While conventional MALDI-TOF MS failed to reliably distinguish T. indotineae from closely related species, unsupervised statistical methods (PCA and hierarchical clustering) revealed distinct spectral groupings. Supervised machine learning algorithms, particularly PLS-DA and SVM, achieved 100% balanced accuracy in species classification using 10-fold cross-validation. Biomarker analysis identified discriminatory spectral peaks for both T. indotineae and T. mentagrophytes (3417.29 m/z and 3423.53 m/z). These results demonstrate that combining MALDI-TOF MS with multivariate analysis and machine learning improves diagnostic resolution and may offer a practical alternative to sequencing in resource-limited settings. This approach could enhance the routine detection of terbinafine-resistant T. indotineae and support more targeted antifungal therapy. Full article

The bulb of Fritillaria species called “Bei Mu” is a well-known traditional Chinese medicine. We have reported some potential off-target effects of “Bei Mu” due to peimine’s blockade of hERG (human Ether-a-go-go-Related Gene) channels. This research investigated the modulatory effects of three major alkaloid analogs of “Bei Mu” and their cooperative effects on hERG channels using manual whole-cell patch-clamp techniques. Results showed that peiminine and sipeimine blocked hERG currents with IC₅₀s of 36.8 ± 2.5 μM and 47.6 ± 9.8 μM, which were close to that of peimine (26.1 ± 3.5 μM). Peiminine-induced blockade increased with increasing depolarizing strengths, durations, and frequencies, which suggested a preferential binding to open or inactivated states. The reduced blockade by the less inactivating S631A mutation supported peiminine‘s inactivation preference. Molecular docking and dynamics simulations confirmed the hERG-blocking activities of the three alkaloids and provided further insight into potential mechanisms. We also discovered antagonistic effects of the three alkaloids at nearly all concentrations tested, which might help reduce potential cardiotoxicities. To our knowledge, this is the first study to investigate combination effects of chemicals from one herb on hERG channels. In conclusion, peiminine and sipeimine can block hERG channels in a way similar to peimine, but antagonistic effects exist among them. Full article

Background/Objectives: Angioimmunoblastic T-cell lymphoma (AITL) is a rare peripheral T-cell lymphoma of follicular helper T-cell (TFH) origin, often associated with immune dysregulation and EBV-positive B-cell proliferation. Kaposi sarcoma (KS) is a vascular neoplasm caused by human herpesvirus 8 (HHV-8), typically arising in immunocompromised individuals. The synchronous occurrence of AITL and KS in HIV-negative patients is exceptionally rare, with only three cases previously reported worldwide. Case Presentation: We describe an 81-year-old HIV-negative Korean woman presenting with progressive generalized edema and dyspnea. Imaging revealed multifocal lymphadenopathy. Excisional biopsy of the inguinal lymph node showed two distinct but adjacent neoplastic processes. The AITL component demonstrated a polymorphous infiltrate of atypical TFH cells expressing CD3, CD4, CD10, PD-1, and Bcl-6, with monoclonal TCR-γ rearrangement and TET2 and RHOA mutations. The KS component comprised spindle cells with slit-like vascular spaces, red blood cell extravasation, and immunoreactivity for HHV-8, CD31, CD34, and ERG. The findings were consistent with a collision tumor. Despite supportive care, the patient’s condition deteriorated, and she was discharged with palliative care. Discussion: The coexistence of AITL and KS in an HIV-negative setting raises important pathogenetic considerations. AITL is characterized by profound immune dysregulation, with depletion of normal T-cell subsets, abnormal B-cell activation, and cytokine milieu changes that may favor latent viral reactivation. This immunologic environment may permit HHV-8 reactivation, thereby facilitating the development of KS even in the absence of overt immunodeficiency due to HIV infection. Our findings support the hypothesis that AITL-related immune dysfunction may create a permissive niche for HHV-8-driven neoplasia. Conclusions: This is the first reported case in Asia and the fourth worldwide of a collision tumor comprising AITL and KS in an HIV-negative patI dient. The case suggests that AITL-associated immune dysregulation may facilitate HHV-8 reactivation and KS development even in the absence of HIV infection. Awareness of this association is critical for accurate diagnosis and optimal patient management. Full article

Background/Objectives: Malassezia pachydermatis is a lipophilic yeast frequently associated with otitis externa and dermatological disorders in companion animals. This study aimed to evaluate the antifungal susceptibility of M. pachydermatis isolates from dogs and cats and to investigate the genomic determinants of reduced susceptibility. Methods: Susceptibility testing of 87 clinical isolates was performed using a modified CLSI broth microdilution method in Sabouraud dextrose broth supplemented with 1% Tween 80. The whole genome of ten representative isolates was sequenced and the genetic factors that are involved in drug resistance were investigated. Results: Ketoconazole, itraconazole, and terbinafine exhibited the highest efficacy, while miconazole and clotrimazole showed reduced activity. Whole genome sequencing revealed single nucleotide polymorphisms (SNPs) in genes that play a key role in the ergosterol biosynthesis pathway, particularly in ERG11 and ERG1. While some specific amino acid substitutions (e.g., K446R in ERG11) were found only in isolates with elevated MIC values, no direct correlation with resistance could be unequivocally established. Conclusions: Genomic analyses also uncovered chromosomal mutations and the heterozygosity of certain isolates, suggesting that complex, multifactorial mechanisms may drive the development of drug resistance. These findings highlight the importance of standardized susceptibility testing and further genomic investigations to promote effective antifungal therapy in veterinary medicine. Full article