Search Results (1,051)

Background/Objectives: Helicobacter pylori (H. pylori) is a common gastric pathogen linked to gastritis, gastroduodenal ulcers, and gastric cancer. Rising antimicrobial resistance (AMR) poses challenges for effective treatment and has prompted the WHO to classify H. pylori as a high-priority pathogen. This study aimed to detect the prevalence of AMR genes in H. pylori-positive gastric samples from patients in Algarve, Portugal, where regional data is scarce. Methods: Eighteen H. pylori-positive gastric biopsy samples from patients undergoing upper gastrointestinal endoscopy were analyzed. PCR and sequencing were used to identify genes associated with resistance to amoxicillin (Pbp1A), metronidazole (rdxA, frxA), tetracycline (16S rRNA mutation) and clarithromycin (23S rRNA). Sequence identity and homologies were verified using tBLASTx and the Comprehensive Antibiotic Resistance Database (CARD). Results: Out of the 18 H. pylori-positive samples, 16 (88.9%) contained at least one AMR gene. The most frequent genes were rdxA (83.3%) and frxA (66.7%) for metronidazole resistance, and the 16S rRNA mutation (66.7%) for tetracycline. Resistance to amoxicillin and clarithromycin was detected in 27.8% and 16.7% of cases, respectively. Most samples (72.2%) had multiple resistance genes. A significantly strong association was found between female sex and the presence of the rdxA gene (p = 0.043). Conclusions: The study reveals a high prevalence of H. pylori resistance genes in Algarve, particularly against metronidazole and tetracycline. These findings highlight the need for local surveillance and tailored treatment strategies. Further research with larger populations is warranted to assess regional resistance patterns and improve eradication efforts. Full article

High-grade serous ovarian cancer (HGSOC) is the most common and aggressive subtype of ovarian cancer, accounting for approximately 70% of cases. This study investigates genetic mutations and their associations with overall survival (OS), complete cytoreduction (R0), and platinum response in patients undergoing either primary debulking surgery followed by adjuvant chemotherapy (PDS) or neoadjuvant chemotherapy followed by interval debulking surgery (NACT). Genetic analysis was performed on 43 primary HGSOC tumor samples using targeted massive parallel sequencing via next-generation sequencing (NGS). Clinical and molecular data were evaluated collectively and through subgroup comparisons between PDS and NACT cohorts. All analyzed samples harbored genetic alterations. Univariate survival analysis revealed that the total number of mutations (p = 0.0035), as well as mutations in HRAS (p = 0.044), FLT3 (p = 0.023), TP53 (p = 0.03), and ERBB4 (p = 0.007), were significantly associated with poorer OS. Multivariate Cox regression integrating clinical and molecular data confirmed that ERBB4 mutations are independently associated with adverse outcomes. These findings reveal a distinctive mutational landscape between the PDS and NACT groups and suggest that ERBB4 alterations may define a particularly aggressive tumor phenotype. This study contributes to a deeper understanding of HGSOC biology and may support the development of novel therapeutic targets and personalized treatment strategies in the context of precision oncology. Full article

The Sprouty (Spry) proteins modulate signalling and regulate processes like cellular migration and proliferation. Here, we investigated a Spry4 alteration substituting a lysine at position 177 to an arginine, based on a mutation found in Kallmann syndrome, a genetically heterogeneous disease connected to reduced fibroblast growth factor receptor1 (FGFR) signalling. Using growth curves to evaluate proliferative and scratch assays to determine migrative capacities of the cells, in normal fibroblasts as well as in osteosarcoma-derived cells, we demonstrate that the modified Spry4^K177R version hinders both processes, which the unaltered protein cannot do under the same conditions. The inhibition of these processes was accompanied by lower relative phospho-extracellular-signal-regulated kinases (pERK) levels in response to serum induction, indicating that activation of MAPK was less efficient. In contrast to the situation in these cells of mesenchymal origin, in lung cancer-derived cell lines both variants of Spry4 were able to interfere with proliferation of tested cells, and in the cells with elevated FGFR1 expression the Spry4 proteins with an alteration at codon 177 were even more effective. In summary, these data indicate that the lysine at position 177 restricts the ability of Spry4 to inhibit signal transduction at least in cells with high FGFR1 levels. Full article

Purpose: The adenoid microbiota plays a key role in adenoid hypertrophy (AH). This study explored the molecular epidemiology and antimicrobial resistance of Haemophilus. Influenzae (H. influenzae) strains in pediatric AH patients. Methods: Retrospective analysis of pediatric AH patients undergoing endoscopic adenoidectomy. Adenoid tissue samples were cultured to screen for pathogens. H. influenzae strains were identified by 16S rRNA sequencing and serotyped via q-PCR. Multilocus sequence typing (MLST) and ftsI gene analysis were conducted using PubMLST. β-lactamase genes (bla_TEM-1, bla_ROB-1) were detected by PCR, and antibiotic susceptibility testing (AST) was performed using the Etest method. For imipenem-resistant strains, the acrRAB efflux pump gene cluster and ompP2 porin gene were sequenced and compared with those of the wild-type strain Rd KW20. Results: Over 8 months, 56 non-duplicate H. influenzae strains were isolated from 386 patients. The detection rate was highest in children under 5 years (30.5%) compared to those aged 5–10 years (13.4%) and 10–15 years (8.7%). Of 49 sub-cultured strains, all were non-typeable H. influenzae (NTHi). MLST identified 22 sequence types (STs) and 13 clonal complexes (CCs), with CC11 (26.5%), CC3 (14.3%), and CC107 (14.3%) being predominant. Common STs included ST103 (22.4%), ST57 (10.2%), and ST107 (10.2%). Most strains belonged to the ftsI group III-like+ (57.1%). β-lactamase positivity was 98.0% (48/49), with bla_TEM-1 (95.9%) and bla_ROB-1 (18.4%) detected. AST showed low susceptibility to ampicillin (10.2%), amoxicillin–clavulanate (34.7%), azithromycin (12.2%), and trimethoprim–sulfamethoxazole (14.3%). Among the β-lactamase-positive strains, 44/48 were β-lactamase-positive ampicillin-resistant (BLPAR); none were β-lactamase-negative ampicillin-resistant (BLNAR). Imipenem susceptibility was 91.8% (45/49). No carbapenemases were found in the imipenem-resistant strains, but mutations in acrRAB (88.12–94.94% identity) and ompP2 (77.10–82.94% identity) were observed. Conclusions: BLPAR NTHi strains of CC11 are major epidemic strains in pediatric AH. Imipenem resistance in H. influenzae likely results from porin mutations rather than carbapenemase activity. Enhanced surveillance of H. influenzae’s role in AH and its resistance patterns is warranted. Full article

Most patients with non-small-cell lung cancer (NSCLC) present with advanced/metastatic disease at diagnosis, and molecular profiling is critical in guiding treatment decisions. This retrospective cohort study aimed to characterize EGFR mutations (EGFRm) in advanced/metastatic NSCLC patients, treatment patterns, and real-world outcomes. Adults diagnosed between 2018 and 2021 and treated at a Comprehensive Care Center were included. Time-to-event outcomes were analyzed using the Kaplan–Meier method. A total of 110 patients were included, with a median age of 69.0 years (range, 37–93), 76.4% female, and 83.2% non-smokers. About 97.3% had adenocarcinomas, with 93.6% at stage IV, 40.9% with ≥ three metastatic sites (brain metastases in 24.5%), 33.6% ECOG 2–4, and 58.2% with an EGFR exon-19 deletion. A minority started supportive care or curative-intent treatment, and 81.8% underwent first-line palliative systemic therapy (TKIs, 91.1%; chemotherapy, 8.9%). Median real-world overall survival (rwOS) was 18.9 months (95% CI, 13.8–28.1). Worse rwOS was observed in patients with ECOG 2–4 versus ECOG 0–1 (10.3 vs. 22.8 months; HR 1.82, 95% CI 1.17–2.85; p = 0.008) and in patients with exon-21 L858R versus exon 19 deletions (15.8 vs. 24.2 months; HR 1.59, 95% CI 1.00–2.54; p = 0.048). In patients treated with palliative systemic treatment, median progression-free survival was 10.9 months (95% CI, 8.8–13.6). This study provides important insights regarding real-world characteristics, treatment patterns, and outcomes from a cohort of EGFRm advanced/metastatic NSCLC patients. Full article

Scavenging domestic ducks significantly contribute to the transmission and maintenance of highly pathogenic H5N1 clade 2.3.4.4b avian influenza viruses in Bangladesh, a strain of growing global concern due to its broad host range, high pathogenicity, and spillover potential. This study investigates the molecular epidemiology and pathology of HPAI H5N1 viruses in unvaccinated scavenging ducks in Bangladesh, with the goal of assessing viral evolution and associated disease outcomes. Between June 2022 and March 2024, 40 scavenging duck flocks were investigated for HPAI outbreaks. Active HPAIV H5N1 infection was detected in 35% (14/40) of the flocks using RT-qPCR. Affected ducks exhibited clinical signs of incoordination, torticollis, and paralysis. Pathological examination revealed prominent meningoencephalitis, encephalopathy and encephalomalacia, along with widespread lesions in the trachea, lungs, liver, and spleen, indicative of systemic HPAIV infection. A phylogenetic analysis of full-genome sequences confirmed the continued circulation of clade 2.3.2.1a genotype G2 in these ducks. Notably, two samples of 2022 and 2023 harbored HPAIV H5N1 of clade 2.3.4.4b, showing genetic similarity to H5N1 strains circulating in Korea and Vietnam. A mutation analysis of the HA protein in clade 2.3.4.4b viruses revealed key substitutions, including T156A (loss of an N-linked glycosylation site), S141P (antigenic site A), and E193R/K (receptor-binding pocket), indicating potential antigenic drift and receptor-binding adaptation compared to clade 2.3.2.1a. The emergence of clade 2.3.4.4b with the first report of neurological and systemic lesions suggests ongoing viral evolution with increased pathogenic potential for ducks. These findings highlight the urgent need for enhanced surveillance and biosecurity to control HPAI spread in Bangladesh. Full article

Leeches hold significant medical and pharmaceutical value for antithrombotic treatments, yet their genetic diversity patterns remain poorly understood. We performed population genetic analyses on seven Hirudinaria manillensis populations from southern China using mitochondrial protein-coding genes (MitPCGs). Complete sequences of all 13 MitPCGs were obtained from 74 individuals. Haplotype diversity exhibited a logarithmic relationship with the gene length (R² = 0.858, p < 0.001), while nucleotide diversity showed a near-perfect alternating low-high pattern (Z = 2.938, p = 0.003). Concatenated sequence analyses indicated high haplotype diversity (>0.5) and low nucleotide diversity (<0.005) across all populations, suggesting a historical bottleneck followed by rapid expansion and mutation accumulation. The haplotype network, haplotype phylogenetics, and genetic structure analyses revealed moderate genetic differentiation across populations, dividing them into three clades: a basal Yunnan population (YNHH), sub-basal Guangxi populations (GXGG, GXLZ, and GXYL), and distal Guangdong/Hainan populations (GDMM, GDZJ, and HNDA). Analysis of historical population demography revealed five phases from ancient to recent times (P1–5): growth, prolonged stability, rapid decline, rapid growth, and secondary decline. These phases correlate strongly with past climatic events, demonstrating that glacial–interglacial cycles profoundly impacted the leech’s effective population size. This study provides a key scientific basis for H. manillensis resource conservation and utilization. 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

Brown spot, caused by Alternaria alternata, is the most important leaf fungal disease threatening kiwifruit production in China, and it is typically controlled through the application of fungicides, such as procymidone and difenoconazole. To date, fungicide resistance development has not yet been systematically reported for the pathogen of kiwifruit. A total of 135 single-conidium A. alternata isolates were collected from different cities in Zhejiang Province, China. Alternaria alternata developed prevailing resistance to procymidone and initial resistance to difenoconazole, with resistance frequencies of 60.7 and 13.3%, respectively. Positive cross-resistance was observed between procymidone and iprodione but not between procymidone and difenoconazole, tebuconazole, prochloraz, pydiflumetofen, pyraclostrobin, or thiophanate-methyl. Moreover, no cross-resistance was observed between difenoconazole and all other tested fungicides, including the two other demethylation inhibitors, tebuconazole and prochloraz. A fitness penalty was not detected in procymidone-resistant (Pro^R) or difenoconazole-resistant (Dif^R) isolates. However, double-resistant (Pro^R Dif^R) isolates had a fitness penalty, showing significantly decreased sporulation, germination, and pathogenicity. The P894L single point mutation, caused by the change from CCA to CTA at the 894th codon of Os1, was detected in Pro^R isolates. Molecular dynamic simulation showed that the P894L mutation significantly decreased the inhibitory activity of procymidone against AaOs1 in A. alternata. These results provide insight into the development and characteristics of fungicide resistance, offering guidance for the study and management of kiwifruit diseases. Full article

Bacterial persisters are dormant cells that survive antibiotic treatment, serving as a reservoir for the emergence of resistant mutations. The evolution of antibiotic resistance poses a significant challenge to public health. In this study, we investigated the development of resistance in Pseudomonas aeruginosa persister cells by exposing the reference strain PA14 to meropenem and tracked the emergence of resistance mutations over serial passages. Whole-genome sequencing of the populations or individual resistant strains revealed evolutionary trajectories. In the initial passages, low-level meropenem-resistant mutants harbored various mutations, accompanied by increasing population survival. Then, mutations in the oprD gene appeared, followed by mutation in the mexR gene in most of the cells, leading to high-level meropenem resistance and collateral resistance to ciprofloxacin. Our study provides insights into the evolutionary pathways of P. aeruginosa under lethal antibiotic pressure, highlighting the dynamic interplay between persister cells and the emergence of resistance mutations. Full article

Klebsiella pneumoniae is a major public health concern due to its role in Gram-negative bacteremia, which leads to high mortality and increased healthcare costs. This study characterizes phenotypic and genomic features of K. pneumoniae isolates from clinical samples in Karachi, Pakistan. Among 507 isolates, 213 (42%) were carbapenem-resistant based on disk diffusion and MIC testing. Urine (29.7%) and blood (28.3%) were the most common sources, with infections predominantly affecting males (64.7%) and individuals aged 50–70 years. Colistin was the only antibiotic showing consistent activity against these isolates. The whole-genome sequencing of 24 carbapenem-resistant K. pneumoniae (CR-KP) isolates revealed bla_NDM-5 (45.8%) as the dominant carbapenemase gene, followed by bla_NDM-1 (12.5%) and bla_OXA-232 (54.2%). Other detected bla_OXA variants included bla_OXA-1, bla_OXA-4, bla_OXA-10, and bla_OXA-18. The predominant beta-lactamase gene was bla_CTX-M-15 (91.6%), followed by bla_CTX-M-163, bla_CTX-M-186, and bla_CTX-M-194. Sequence types ST147, ST231, ST29, and ST11 were associated with resistance. Plasmid profiling revealed IncR (61.5%), IncL (15.4%), and IncC (7.7%) as common plasmid types. Importantly, resistance was driven not only by acquired genes but also by chromosomal mutations. Porin mutations in OmpK36 and OmpK37 (e.g., P170M, I128M, N230G, A217S) reduced drug influx, while acrR and ramR mutations (e.g., P161R, G164A, P157*) led to efflux pump overexpression, enhancing resistance to fluoroquinolones and tigecycline. These findings highlight a complex resistance landscape driven by diverse carbapenemases and ESBLs, underlining the urgent need for robust antimicrobial stewardship and surveillance strategies. Full article

Objectives: This study aims to describe the clinical features and genetic findings of nine Vietnamese patients with autosomal recessive bestrophinopathy. Methods: This retrospective and cross-sectional study included individuals diagnosed with autosomal recessive bestrophinopathy at the Eye Clinic, Vietnam National Geriatric Hospital between May 2024 and April 2025. The patients underwent a visual acuity assessment, retinal multimodal imaging, and molecular testing through BEST1 gene sequencing. Results: Nine patients from seven unrelated families were included. The mean age was 38.6 years (range: 14.1–79.6). Visual acuity ranged from 20/20 to 20/125. All patients showed vitelliform lesions, subretinal deposits, and both intraretinal and subretinal fluid. Other main features included diffuse macular hyperfluorescence and hyperopia. Less common clinical features encompassed glaucoma, retinoschisis, outer retinal thinning, serous retinal detachment, retinal thickening, and thinning of the retinal pigment epithelium. Compound heterozygous or homozygous variants were detected in all patients. Among the five identified BEST1 variants, the most frequent were p.(A195V) and p.(R200*). One novel variant, p.(K289*), was detected. Conclusions: The main clinical retinal features of nine Vietnamese patients with autosomal recessive bestrophinopathy included vitelliform lesions, subretinal deposits, retinal fluid, and diffuse macular hyperfluorescence. The most common variants were p.(A195V) and p.(R200*). Additionally, the identification of various compound heterozygotes and a novel BEST1 variant expands the mutation spectrum of the disease. Full article

Background/Objectives: Recombinant Fc proteins have been produced that have a protective effect in mouse models of arthritis, such as the K/BxN rheumatoid arthritis model. We have previously shown that a recombinant human IgG1 Fc with a point mutation at position 309, replacing a leucine with a cysteine, fused to the human IgM tailpiece to form a human IgG1 Fc hexamer, rFc-µTP-L309C, effectively prevents neutrophil infiltration into the joints and ameliorates arthritis in the K/BxN serum transfer model and in the endogenous chronic arthritis K/BxN model. We have now investigated the effect of rFc-µTP-L309C on T-cells in the K/BxN chronic arthritis mouse model. Methods: PBMCs were isolated from the spleen, lymph nodes and joint synovial fluid from K/BxN mice having severe chronic arthritis that had been treated with 200 mg/kg rFc-µTP-L309C or human serum albumin (HSA). Flow cytometry was used to isolate the activated CD4⁺CD44⁺ T-cells and T-regulatory cells (Tregs). Intracellular staining was used to identify Th1 and Th17 T-cell subsets, and CD4⁺CD25⁺FoxP3⁺ Tregs. ELISA was used to measure levels of IL-10 and TGF-β in synovial fluid. Results: We find that amelioration of the arthritis occurs after treatment with rFc-µTP-L309C and results in a decrease in Th1 cells’ production of IFNγ and Th17 cells’ production of IL-17. Amelioration also results in decreased production of GM-CSF. Moreover, amelioration results in increased Tregs and IL-10 production in the synovial fluid. Conclusions: rFc-µTP-L309C reduces the inflammatory T-cells and increases the regulatory anti-inflammatory T-cells in the chronic arthritis K/BxN mouse model. This effect explains, in part, the ability of rFc-µTP-L309C to ameliorate the arthritis and reduce damage on the articular cartilage of K/BxN mice. Full article

Osteogenesis imperfecta (OI) is a rare bone dysplasia that occurs with a frequency of 1/15,000–20,000 live births. It is characterized by increased susceptibility of bone fractures, skeletal deformities, low stature, and low bone mass. It results in impaired production of type I collagen. About 90% of people with OI have heterozygous mutations in the COL1A1 and COL1A2 genes. Fibroblast growth factor 23 (FGF23) is a protein involved in the regulation of phosphate and 1,25-dihydroxyvitamin D₃ metabolism on a negative feedback basis. FGF23 is secreted by osteocytes in response to increased serum calcitriol and phosphorus. The purpose of this study was to evaluate the concentration of FGF23 among children with osteogenesis imperfecta and the differences in reference values in a healthy population of children and adolescents. Then, this study sought to evaluate how the course of osteogenesis imperfecta, including type of disease, number of bone fractures, and bone mineral density, are related to FGF23 concentration. The study included 47 children aged 3 to 17 years with a diagnosis of osteogenesis imperfecta, confirmed by genetic tests. The patients were hospitalized at the Department from August 2019 to September 2020 and were treated with intravenous infusions of sodium pamidronate. The course of the disease was analyzed, including the number of bone fractures, clinical symptoms, and anthropometric parameters, and bone densitometry was performed by dual X-ray absorptiometry (DXA) in Total Body Less Head (TBLH) and Spine options with Z-score evaluation. FGF23 concentration was determined by the ELISA method. The study was prospective in nature. Results: The mean level of FGF23 in the study group of patients was 645.09 pg/mL and was within the reference values for the developmental age population. There was no significant correlation between FGF23 concentration and anthropometric measurements: body weight (p = 0.267), height (p = 0.429), gender (p = 0.291), or pubertal stage (p = 0.223) in the study group of patients. FGF23 levels were not related to the number of fractures (p = 0.749), the number of sodium pamidronate cycles administered (p = 0.580), bone mineral density parameters (Z-score), the form of osteogenesis imperfecta (p = 0.156), or the genetic test result (p = 0.573). FGF23 levels decrease with age (r = −0.32, p = 0.030) and BMI (r = −0.34, p = 0.020). The level of FGF23 in patients with osteogenesis imperfecta is lower among older children and those having a higher BMI. This index cannot be a diagnostic tool in this group of patients, for no differences were found between the concentrations in patients with osteogenesis imperfecta and the developmental age population. Full article

Collagen II is a vital structural component in developing bones and mature cartilage. Mutations in this protein cause spondyloepiphyseal dysplasia, a disease characterized primarily by altered skeletal growth and manifesting with a range of phenotypes, from lethal to mild. This study examined transgenic mice harboring the R992C (p.R1124C) substitution in collagen II. Previous research demonstrated significant growth abnormalities and disorganized growth plate structure in these mice, and histological signs of osteoarthritic changes in the knee joints of 9-month-old mice with the R992C mutation. Our study focuses on detecting early structural changes in the articular cartilage that occur before histological signs become apparent. Through microscopic and spectroscopic analyses, we observed significant alterations in the distribution gradients of collagenous proteins and proteoglycans in the cartilage of R992C mutant mice. We propose that these early changes, eventually leading to articular cartilage degeneration in older mice, underscore the progressive nature of osteoarthritic changes linked to collagen II mutations. By identifying these early structural aberrations, our findings emphasize the importance of early detection of osteoarthritic changes, potentially facilitating timely, non-surgical interventions. Full article