Search Results (75)

Background: Dominantly acting variants in TUBB2B have primarily been associated with cortical dysplasia complex with other brain malformations 7 (CDCBM7), a disorder in which cortical brain abnormalities are typically linked to developmental delay/intellectual disability (DD/ID) and seizures. While the majority of TUBB2B pathogenic variants have been linked to isolated CDCBM7, only one family with CDCBM7 and congenital fibrosis of the extraocular muscles (CFEOM) has been reported so far. We describe a second individual with a severe phenotype of CFEOM combined with CDCBM7 carrying a pathogenic TUBB2B missense variant previously reported in two individuals with isolated CDCBM7. Methods: A trio-based WGS analysis was performed. The structural impact of the identified substitution was assessed by using the UCSF Chimera (v.1.17.3) software and PyMOL docking plugin DockingPie tool. Results: WGS analysis identified a de novo missense TUBB2B variant (p.Ile202Thr, NM_178012.5), previously associated with isolated CDCBM7. Structural analysis and docking simulations revealed that Ile202 contributes to establishing a proper hydrophobic environment required to stabilize GTP/GDP in the β-tubulin pocket. p.Ile202Thr was predicted to disrupt these interactions. Conclusions: Our findings broaden the mutational spectrum of TUBB2B-related CFEOM, targeting a different functional domain of the protein, and further document the occurrence of phenotypic heterogeneity. We also highlight the limitations of exome sequencing in accurately mapping TUBB2B coding exons due to its high sequence homology with TUBB2A and suggest targeted or genome analyses when clinical suspicion is strong. Full article

Background: Maturity-onset diabetes of the young (MODY) is a heterogeneous group of monogenic diabetes forms that are frequently misclassified as type 1 or type 2 diabetes due to overlapping phenotypic features. The true prevalence of MODY is likely substantially underestimated. As DNA-based diagnostics become increasingly accessible, an expanding number of novel genetic variants are being identified. Objectives: The aim of this study was to characterize the clinical and genetic features of patients carrying rare variants in the BLK, KLF11, PAX4, PDX1, and CEL genes, with attention to population-specific aspects, family history, and treatment outcomes. Methods: Targeted next-generation sequencing (NGS) using a custom-designed panel covering 27 genes implicated in MODY, neonatal diabetes, and related hereditary syndromes was performed on the Illumina NovaSeq 6000 platform (Illumina). Results: We identified 21 variants in five genes associated with rare MODY subtypes among 24 unrelated patients. MODY9 was diagnosed in two unrelated patients of Russian ethnicity harboring an identical heterozygous missense mutation in exon 5 of the PAX4 gene (HG38, chr7:127615049G>A, c.191C>T, p.Thr64Ile), which has not been previously described in patients with diabetes. MODY11 was diagnosed in a patient carrying the c.773-1G>A variant in the BLK gene. A patient with a de novo c.40_41dupGC (p.Val15Glnfs*41) variant in the KLF11 gene was clinically diagnosed with type 1 diabetes. Conclusion: Our findings expand the current understanding of rare MODY subtypes and contribute to the growing body of evidence on the spectrum and frequency of potentially pathogenic variants in BLK, CEL, KLF11, PDX1, and PAX4 genes across ethnically diverse populations worldwide. Full article

Background: Campylobacter spp. are leading foodborne pathogens, with increasing antimicrobial resistance (AMR) posing a critical public health threat. While broiler chickens have been widely studied, turkeys represent an underexplored reservoir. The present study investigates Campylobacter spp. in turkeys, focusing on isolation frequency, resistance, and virulence within the context of One Health. Methods: A total of 182 cecal samples were collected from slaughtered turkeys in Romania. Isolation and identification of Campylobacter jejuni and C. coli followed ISO 10272-1:2017 guidelines. Antimicrobial susceptibility testing was conducted via broth microdilution, and molecular analyses using PCR targeted species identification, resistance determinants, and virulence-associated genes. Results: Campylobacter spp. were detected in 75.8% of samples, with C. jejuni and C. coli accounting for 54.3% and 45.7%, respectively. High resistance rates were observed to ciprofloxacin (89.9%) and tetracycline (85.5%), with moderate resistance to erythromycin and ertapenem. No resistance was found to gentamicin or chloramphenicol. Genotypic analyses confirmed the presence of resistance genes (e.g., tetO, gyrA—Thr-86-Ile mutation, ermB, cmeB) and widespread virulence genes (flaA, cadF, cdtAB, ciaB), supporting phenotypic results. Conclusions: The survey highlights turkeys as a significant but neglected source of resistant and virulent Campylobacter spp., with implications for food safety and public health. The convergence of AMR and virulence aspects calls for integrated surveillance and control strategies across veterinary and human health sectors, supporting the One Health strategy. Full article

Background: Genetic alterations in CSF3R, typically associated with chronic neutrophilic leukemia (CNL) and atypical chronic myeloid leukemia (aCML), rarely occur in other myeloid neoplasms. Methods: This study characterized the clinical, morphologic, cytogenetic, and molecular features of 13 patients with non-CNL non-aCML myeloid neoplasms with CSF3R alterations. Patients (median age, 77 years) were categorized into groups with a myelodysplastic/myeloproliferative neoplasm (MDS/MPN) (n = 5), acute leukemia (n = 4), and other myeloid neoplasms (n = 4) based on the WHO 2022 and ICC criteria. Results: The CSF3R p.Thr618Ile mutation was most frequent (11/13), with additional pathogenic variants including p.Gln743Ter and frameshift mutations affecting the cytoplasmic tail. Variant allele frequencies (VAFs) ranged from 2% to 49%, with the highest median VAF in the MDS/MPN group. Co-mutations varied by subtype; MDS/MPN, NOS, and CMML cases frequently harbored mutations in epigenetic regulators (ASXL1, TET2) and splicing factors (SF3B1, SRSF2, ZRSR2), while acute leukemia cases showed alterations in JAK3, STAT3, and NRAS. Survival analysis revealed distinct patterns across the three diagnostic groups, with MDS/MPN having the poorest prognosis. Conclusion: This study expands the recognized spectrum of CSF3R-related myeloid neoplasms and highlights the clinical and molecular heterogeneity associated with these mutations, emphasizing the need for comprehensive molecular profiling and the potential for targeted therapies. Full article

To genetically characterise an epidemic isolate of feline panleukopenia virus (FPLV) harbouring the Ala91Ser mutation in China, a clinical strain (accession number: OR921195.1), named FPLV-CC19-02, was isolated from a PCR-positive faecal swab sample. Phylogenetic analysis revealed that it is far removed from all current commercial vaccine strains and differs from the FPLV prototype strain Cu-4 (M38246.1), specifically the vaccine strain of Fel-O-Vax^® PCT, at positions 91 (Ala91Ser) and 101 (Ile101Thr) within the VP2 protein. This virus can induce the typical cytopathic effect seen in parvovirus infection in feline kidney cells, resulting in severe clinical symptoms in cats, including haematochezia and hyperthermia. Furthermore, infected cats died of virus infection within 5–10 days post-infection (dpi) (100% morbidity and 83% mortality), indicating that FPLV-CC19-02 is a strain with increased virulence. Additionally, it demonstrated good immunogenicity in cats. Overall, these findings may help us to better understand the molecular prevalence of feline panleukopenia virus in cats and provide valuable basic data for the development of effective, locally adapted feline panleukopenia virus vaccines in China. Full article

Background: In this study, molecular mechanisms contributing to delafloxacin resistance in Pseudomonas aeruginosa strains were investigated. Delafloxacin is a recently approved fluoroquinolone currently introduced to clinical applications. Methods: A total of 52 P. aeruginosa strains were collected from clinical isolates. Antimicrobial susceptibility testing was performed via broth microdilution, and the minimum inhibitory concentration (MIC) values for ciprofloxacin, levofloxacin, delafloxacin, ceftazidime and imipenem were determined. Five delafloxacin-resistant P. aeruginosa strains were selected for whole-genome sequencing (WGS). Results: MIC50 values were determined, and the following results were obtained: ciprofloxacin 0.25 mg/L, levofloxacin 0.25 mg/L and delafloxacin 1 mg/L. All five selected strains showed both extended-spectrum beta-lactamase and carbapenemase production. WGS analysis of these strains determined the sequence types (STs), namely, ST235 (two strains), ST316 (two strains) and ST395. Several mutations in quinolone-resistance-determining regions (QRDRs) were detected in all five delafloxacin-resistant P. aeruginosa strains as follows: gyrA Thr83Ile and parC Ser87Leu mutations were present in all five strains, while parE Thr223Ala in ST235, Glu459Val in ST316 and Val200Met in ST395 were detected. MexAB-OprM and MexCD-OprJ efflux pumps were uniformly present in all delafloxacin-resistant P. aeruginosa strains. All strains of ST235 and ST316 carried bla_NDM-1 in combination with other beta-lactamases. In our study, the in vitro efficacy of delafloxacin is inferior compared to previous fluoroquinolones based on MIC50 values; however, MIC values of delafloxacin ranged between 0.125 and 128 mg/L in our P. aeruginosa collection, and 21 out of 52 strains showed susceptibility to delafloxacin. Conclusions: Multiple QRDR mutations combined with several efflux pumps confer delafloxacin resistance in P. aeruginosa. Among the different detected multidrug-resistant P. aeruginosa strains in this study, we also report on an NDM-1 producing P. aeruginosa ST316 in Hungary. Full article

Background/Objectives: The World Health Organization has recognized Pseudomonas aeruginosa as a multidrug-resistant bacterium that presents public health concerns. This study aimed to evaluate the prevalence of MDR P. aeruginosa isolates along with their susceptibility profiles and determine the genetic basis of resistance. Methods: A total of 100 P. aeruginosa isolates were cultured on MacConkey agar with various specimens from patients admitted to ICUs and wards. Species identification was performed for each isolate using the VITEK^® 2 system. Each isolate was tested for susceptibility to specific antibiotics by the broth microdilution method. The resistance genes were detected by molecular methods, i.e., PCR and Sangar sequencing. Results: Among the 100 P. aeruginosa isolates tested phenotypically, 33 MDR P. aeruginosa isolates were detected. The aminoglycoside group of antibiotics showed the least resistance against P. aeruginosa, with increasing resistance to carbapenems and ciprofloxacin. The most prevalent detected genes responsible for resistance were blaVEB, blaVIM, aac (6′)-Ib, and qnr S. DNA sequencing results for the MDR isolates showed that 14 isolates had Thr-83> Ile mutation in gyrA, and 12 isolates had Ser-87>Leu mutation in parC genes. Conclusions: We conclude that the low rates of resistance to certain antibiotics, such as amikacin and piperacillin-tazobactam, seem encouraging to be effective for the treatment of Pseudomonas infections. Furthermore, the prominent mechanisms of resistance to fluoroquinolones in clinical strains of P. aeruginosa include mutations in gyrA and parC genes. These findings highlight the necessity of molecular diagnostics in guiding therapy and the potential need for broader surveillance. Full article

Background/Objectives: Terbinafine has been the gold standard for the management of superficial fungal infections. The etiological agent generally is Trichophyton rubrum (T. rubrum); however, there has been increased reporting of a new terbinafine-resistant strain of the T. mentagrophytes complex (T. mentagrophytes ITS genotype VIII otherwise known as T. indotineae). Here, we review the epidemiology, clinical features, diagnosis, and treatment of T. rubrum and T. indotineae infections. Methods: We conducted a systematic literature search using PubMed, Embase (Ovid), and Web of Science, resulting in 83 qualified studies with data summarized for clinical features, antifungal susceptibility, and terbinafine resistance mechanisms and mutations. Results: Dermatophytosis is most commonly caused by T. rubrum; however, in certain parts of the world, especially in the Indian subcontinent, T. indotineae infections have been reported more frequently. The majority of T. rubrum isolates remain susceptible to terbinafine (over 60% of isolates show MIC₅₀ and MIC₉₀ < 0.5 µg/mL). In contrast, for T. indotineae, 30% of isolates exhibit MIC₅₀ ≥ 0.5 µg/mL and 80% exhibit MIC₉₀ ≥ 0.5 µg/mL. Frequently detected squalene epoxidase (SQLE) mutations in T. rubrum are Phe397Leu/Ile (41.6%) and Leu393Phe (20.8%); in T. indotineae, these include Phe397Leu (33.0%) and Ala448Thr (24.5%). Other potential terbinafine resistance mechanisms in T. rubrum and T. indotineae are discussed. Conclusions: T. rubrum generally remain susceptible in vitro to terbinafine in contrast to T. indotineae. The essential components of an effective antifungal stewardship emphasize accurate clinical and laboratory diagnosis, susceptibility testing, and appropriate antifungal therapy selection with a multidisciplinary approach. Full article

The tetrameric protein transthyretin (TTR) transports the hormone thyroxine in plasma and cerebrospinal fluid. Certain point mutations of TTR, including the Val122Ile mutation investigated here, destabilize the tetramer leading to its dissociation, misfolding, aggregation, and the eventual buildup of amyloid fibrils in the myocardium. Cioffi et al. reported the design and synthesis of a novel TTR kinetic stabilizing ligand, referred to here as TKS14, that inhibited TTR dissociation and amyloid fibril formation. In this study, molecular dynamics simulations were used to investigate the binding of TKS14 and eight TSK14 derivatives to the Val122Ile TTR mutant. For each complex, the ligand’s solvent accessible surface area (SASA), ligand–receptor hydrogen-bonding interactions, and the free energy of ligand-binding to TTR were investigated. The goal of this study was to identify the TSK14 functional groups that contributed to TTR stabilization. TKS14 was found to form a stable, two-point interaction with TTR by hydrogen bonding to Ser-117 residues in the inner receptor binding pocket and interacting through hydrogen bonds and electrostatically with Lys-15 residues near the receptor’s surface. The free energy of TKS14-TTR binding was −18.0 kcal mol⁻¹ and the ligand’s average SASA value decreased by over 80% upon binding to the receptor. The thermodynamic favorability of TTR binding decreased when TKS14 derivatives contained either methyl ester, amide, tetrazole, or N-methyl functional groups that disrupted the above two-point interaction. One derivative in which a tetrazole ring was added to TKS14 was found to form hydrogen bonds with Thr-106, Thr-119, Ser-117, and Lys-15 residues. This derivative had a free energy of TTR binding of −21.4 kcal mol⁻¹. Overall, the molecular dynamics simulations showed that the functional groups within the TKS14 structural template can be tuned to optimize the thermodynamic favorability of ligand binding. Full article

Background: Homocystinuria caused by cystathionine β-synthase (CBS) deficiency is the most common congenital disorder related to sulfur amino acid metabolism, manifested by neurological, vascular, and connective tissue involvement. Methods: This study analyzed the pathogenic gene and molecular mechanism of two classic homocystinuria families through whole exome sequencing and in vitro experiments including minigene assay and expression analysis. Results: Both probands presented with ectopia lentis, high myopia, and abnormally elevated homocysteine level, but one of them had more severe clinical manifestations, including general growth retardation, mild intellectual disability, and severe pectus excavatum. Their family members were phenotypically normal but presented slightly higher levels of homocysteine in plasma. Whole exome sequencing revealed that the two probands carried c.833T>C (p.Ile278Thr) and c.1359-1G>C, and c.919G>A (p.Gly307Ser) and c.131delT (p.Tle44Thrfs*38) compound heterozygous mutations in the CBS gene, respectively. Bioinformatics and in vitro functional analysis showed that the c.1359-1G>C mutation affects the normal splicing of CBS gene, resulting in the production of two abnormal transcripts and the production of two truncated proteins. One of the c.1359-1G>C splicing events (c.1359_1467del) and c.131delT (p.Tle44Thrfs*38) both lead to a significant decrease in CBS mRNA and protein levels. Conclusions: Accurate diagnosis of patients with homocystinuria is of great importance for timely and effective treatment, as well as for the provision of appropriate genetic counseling and prenatal diagnosis guidance to the affected families. Full article

Introduction. Hereditary transthyretin amyloidosis (hATTR) is a rare disorder with a largely variable worldwide prevalence, and it is caused by autosomal dominant mutations in the transthyretin (TTR) gene, leading to cardiological, neurological, or mixed phenotypes. Apart from the Glu89Gln, Phe64Leu, and Thr49Ala variants, recently, other mutations of TTR gene have been reported in Sicily (His90Asn, Val122Ile, Ser77Phe, Val20Ala). With this paper, we describe a novel mutation in the TTR gene, the Glu61Ala variant, which had been previously reported in only one case with a cardiac phenotype, and the clinical findings surrounding it. Materials and Methods. One individual affected by chronic idiopathic polyneuropathy and a major red flag for hATTR underwent genetic testing to look for mutations in the TTR gene. Then, his relatives were subjected to the same test. We assessed the anamnestic profile and conducted general and neurological examination, blood tests, nerve conduction studies (NCS), electrocardiogram, and Sudoscan for each patient. Written informed consent was acquired for every patient. Results. Among 7 patients screened, 5 patients carried the Glu61Ala variant (71%). The mean age was 64.6 ± 10.2 years, whereas the mean age at onset was 59.4 ± 7.9 years. In our study, three patients (60%) showed a mixed phenotype, whereas two of them (40%) showed a neurological phenotype. Discussion. The Glu61Ala variant was reported only in one case with a cardiological phenotype, but our patients showed both neurological and cardiological involvement. Further studies are needed to improve knowledge of this genetic variant. Full article

Beckmannia syzigachne is one of the most competitive weeds in winter wheat fields in China. In this study, 120 suspected resistant populations of Beckmannia syzigachne were collected from the Anhui, Hubei, Jiangsu, and Shandong Provinces from 2017 to 2019. In total, 110 populations exhibited different levels of resistance to clodinafop-propargyl, 114 populations expressed different levels of resistance to mesosulfuron-methyl, and 105 populations were resistant to both herbicides at different levels. The resistant weeds were mainly distributed in Anhui and Jiangsu Provinces. The detection results of acetyl coA carboxylase (ACCase) and acetolactate synthase (ALS) genes in the resistant populations indicated that ACCase gene mutations occurred in 97 out of 110 populations resistant to clodinafop-propargyl and ALS gene mutations occurred in 25 out of 114 populations resistant to mesosulfuron-methyl. There were several mutation types, including Ile-1781-Leu, Trp-2027-Cys, Ile-2041-Asn, Ile-2041-Val, Asp-2078-Gly, and Gly-2096-Ala in the ACCase sequence and Pro-197-Ser, Pro-197-Thr, Pro-197-His, Pro-197-Leu, Asp-376-Glu, and Trp-574-Leu in the ALS sequence. Among these mutation types, Pro-197-His, Asp-376-Glu, and Trp-574-Leu in the ALS sequence were the first identified in Beckmannia syzigachne. Full article

Background: The study presents a detailed examination and follow-up of a Slovenian patient with an Leber Hereditary Optic Neuropathy (LHON)-like phenotype and bilateral optic neuropathy in whom genetic analysis identified a novel variant MT-CYB:m.15309T>C (Ile188Thr). Methods: We provide detailed analysis of the clinical examinations of a male patient with bilateral optic neuropathy from the acute stage to 8 years of follow-up. Complete ophthalmological exam, electrophysiology and optical coherence tomography (OCT) segmentation were performed. The genotype analysis was performed with a complete screening of the mitochondrial genome. Furthermore, proteomic analysis of the protein structure and function was performed to assess the pathogenicity of a novel variant of unknown significance. Mitochondrial function analysis of the patient’s peripheral blood mononuclear cells (PBMCs) was performed with the objective of evaluating the mutation effect on mitochondrial function using flow cytometry and high-resolution respirometry. Results: The patient had a profound consecutive bilateral visual loss at 19 years of age due to optic neuropathy with characteristics of LHON; however, unlike patients with typical LHON, the patient experienced a fluctuation in visual function and significant late recovery. He had a total of three visual acuity deteriorations and improvements in the left eye, with concomitant visual loss in the right eye and a final visual acuity drop reaching nadir 9 months after onset. The visual loss was characterized by centrocecal scotoma, abnormal color vision and abnormal VEP, while deterioration of PERG N95 followed with a lag of several months. The OCT examination showed retinal nerve fiber layer thinning matching disease progression. Following a two-year period of legal blindness, the patient’s visual function started to improve, and over the course of 5 years, it reached 0.5 and 0.7 Snellen (0.3 and 0.15 LogMAR) visual acuity (VA). Mitochondrial sequencing identified a presumably pathogenic variant m.15309T>C in the MT-CYB gene at 65% heteroplasmy, belonging to haplogroup K. Mitochondrial function assessment of the patient’s PBMCs showed a lower respiration rate, an increase in reactive oxygen species production and the presence of mitochondrial depolarization, compared to an age- and sex-matched healthy control’s PBMCs. Conclusions: A novel variant in the MT-CYB:m.15309T>C (Ile188Thr) gene was identified in a patient with optic nerve damage and the LHON phenotype without any additional systemic features and atypical presentation of the disease with late onset of visual function recovery. The pathogenicity of the variant is supported by proteomic analysis and the mitochondrial dysfunction observed in the patient’s PBMCs. Full article

Canine parvovirus type-2 (CPV-2), the primary causative agent of serious canine enteric diseases, is highly contagious and associated with high fatality rates worldwide. To comprehend the current emergence of CPV-2 in central and eastern China, 130 rectal swabs from domestic or stray dogs with gastroenteritis symptoms were collected during 2020–2023. A total of 118 positive samples were detected via polymerase chain reaction, and further used to amplify and sequence the VP2 gene. Sequence analysis of the deduced amino acids of VP2 protein indicated that CPV-2c was the most prevalent variant (n = 106, 89.83%), followed by the novel CPV-2a (n = 10, 8.47%) and CPV-2b (n = 2, 1.69%) variants. The VP2 protein from the obtained and reference strains showed 86.95% (AH2103 and HB2108) to 99.94% identity. Based on the nine predicted recombination events, some prevalent CPV-2c strains were highly similar to previously isolated strains, indicating their complex evolution and recombination. The predicted analysis suggested that mutations in the antigen epitope (Val219Ile, Phe267Tyr, and Asn426Glu) and other mutations (Met87Leu, Ile101Thr, and Ser297Ala) affect the tertiary structure of the VP2 protein. This research will help us understand the recent evolution and mutation of Chinese CPV-2 and provide suggestions for updating the CPV-2 vaccine. Full article

Background/Objectives: The genetic underpinnings of Parkinson’s disease (PD) and parkinsonism have drawn increasing attention in recent years. Mutations in the Factor-Induced Gene 4 (FIG4) have been implicated in various neurological disorders, including Charcot-Marie-Tooth disease type 4J (CMT4J), amyotrophic lateral sclerosis (ALS), and Yunis-Varón syndrome. This review aims to explore the association between FIG4 mutations and parkinsonism, with a specific focus on the rare missense mutation p.Ile41Thr (I41T). Methods: We identified 12 cases from 10 different families in which parkinsonism was reported in conjunction with CMT4J polyneuropathy. All cases involved the I41T mutation in a compound heterozygous state, combined with a FIG4 loss-of-function mutation. Data from clinical observations, neuroimaging studies, and genetic analyses were evaluated to understand the characteristics of parkinsonism in these patients. Results: In all 12 cases, parkinsonism developed either concurrently or following the onset of CMT4J neuropathy, but was never observed in isolation. Cases of both early- and late-onset parkinsonism were identified, reflecting similarities to genetic forms of parkinsonism with autosomal recessive inheritance. Imaging studies, including Dopamine transporter Single Photon Emission Computed Tomography (DaTscan) and brain magnetic resonance imaging (MRI), revealed abnormalities indicative of neurodegeneration, consistent with findings in other neurodegenerative disorders. Conclusions: The co-occurrence of parkinsonism with CMT4J in patients carrying the I41T mutation suggests an expanded spectrum of FIG4-related disorders, potentially implicating the same molecular mechanisms seen in other neurodegenerative disorders. Further research into FIG4-mediated pathways may offer valuable insights into potential therapeutic targets for disorders of both the central and peripheral nervous systems. Full article