PCR Sequencing Research Articles

Population genetics and molecular xenomonitoring of Biomphalaria freshwater snails along the southern shoreline of Lake Malawi, Malawi

BackgroundIntestinal schistosomiasis was confirmed endemic in Mangochi District, Malawi, in May of 2018 following an unexpected encounter with discreet populations of Biomphalaria spp. freshwater snails during routine malacological surveillance activities. Since then, only limited malacological surveillance of Biomphalaria has been carried out, and so the distribution of Biomphalaria populations in this area is currently unclear. Additionally, sites of active Schistosoma mansoni transmission in this area are also unknown. In the present study, through extensive malacological surveillance, we aimed to formally document the distribution of Biomphalaria in Mangochi District. We also aimed to identify active intestinal schistosomiasis transmission sites in this area through subjecting all collected Biomphalaria to a recently developed S. mansoni-specific molecular xenomonitoring PCR.MethodsThree malacological surveys were carried out along the southern shoreline of Lake Malawi, Mangochi District, Malawi, in November 2021, July 2022 and October/November 2022. All collected Biomphalaria were subjected to cercarial shedding analysis to identify active Schistosoma infections. Shed cercariae were then genotyped to species level using a standard multi-locus PCR and Sanger sequencing protocol. Following this, a subset of Biomphalaria from each collection site were also genotyped to species level using a standard PCR and Sanger sequencing protocol. All collected Biomphalaria were then subjected to a recently developed S. mansoni-specific molecular xenomonitoring PCR to identify infected, but non-shedding, Biomphalaria.ResultsA total of 589 Biomphalaria were collected across all three surveys. One single Biomphalaria (0.17%) specimen was found to be actively shedding Schistosoma cercariae, which were molecularly confirmed as S. mansoni. All genotyped Biomphalaria (n = 42) were molecularly identified as B. pfeifferi. A further 19 Biomphalaria specimens, collected from four different surveillance sites, were found to be infected with S. mansoni through molecular xenomonitoring. Intestinal schistosomiasis transmission was therefore identified at four different foci in Mangochi District.ConclusionsOur study highlights the importance of molecular approaches to investigate Biomphalaria populations and monitor Biomphalaria-associated intestinal schistosomiasis transmission in endemic areas. As such, the continued development and use of such approaches, in particular the development and use of molecular xenomonitoring assays that can be carried out in resource-poor schistosomiasis-endemic settings, is encouraged. The revision of ongoing schistosomiasis control programmes in Mangochi District, in line with WHO recommendations, is also encouraged.Graphical abstract

Prevalence of non-tuberculous mycobacteria among people with acid-fast positive presumptive tuberculosis in Mali.

Non-tuberculous mycobacteria (NTM) are environmental agents that can cause opportunistic pulmonary disease in humans and animals, often misdiagnosed as tuberculosis (TB). In this study, we describe the cases of NTM identified during the first national anti-TB drug resistance survey conducted in Mali and explore associated risk factors. Sputum was collected from people presenting for pulmonary TB diagnosis from April to December 2019, regardless of age. Microscopy-positive patients were enrolled and tested using the Xpert MTB/RIF assay. A patient who tested negative for the Mycobacterium tuberculosis complex (MTBC) was tested for the presence of mycobacteria by amplification of the IS6110 and 16SrRNA (16S) genes through double quantitative real-time PCR, followed by nested PCR and Sanger sequencing of the IS6110-negative samples for NTM species identification. 1,418 sputum smear-positive patients were enrolled, including 1,199 new cases, 211 previously treated cases, and 8 whose previous treatment history was unknown. Based on the results of Xpert MTB/RIF assay and in-house PCR methods, 1,331 (93.9%) patients were positive for MTBC, 48 (3.4%) for NTM, and no species identification was possible for 39 (2.7%). Advanced age of 65 and over with an OR 8.8 (95% CI 2.3-33.2 and p = 0.001) and previous TB treatment with an OR 3.4 (95% CI 1.2-9.6 and p = 0.016) were the risk factors statistically associated with NTM detection. M. avium complex (MAC) was the predominant NTM species, detected in 20 cases. Detection of NTM in people presumed to have TB is an ongoing challenge, confounding correct TB diagnosis. Concomitant use of microscopy and GeneXpert testing among at-risk individuals could improve patient management.

Molecular identification, genetic diversity, and secondary structure predictions of Physalis species using ITS2 DNA barcoding

BackgroundThe genus Physalis belongs to the Solanaceae family and has different species with important nutritional and medicinal values. Species within this genus have limited morphological differences, a characteristic that hinders accurate identification, safe utilization and genetic conservation of promising genotypes. In addition, to prevent the perceived loss of Physalis diversity due to habitat destruction, species delimitation needs attention. In this study, we used the sequence and structural information of the internal transcribed spacer 2 (ITS2) barcode to efficiently identify and discriminate Physalis species from a collection of 34 Physalis accessions.MethodologyPhysalis plant samples were collected from eight Counties in Kenya based on the availability of the germplasm. The voucher specimens were identified using the botanical taxonomy method and were deposited in the University of Nairobi herbarium. A total of 34 Physalis accessions were identified and accessed for diversity based on the ITS2 barcode region. The sequence similarity of the ITS2 genes was analyzed through the Basic Local Alignment Search Tool (BLAST), the nearest Kimura-2-parameter (K2P) genetic distances were calculated and a phylogenetic tree was constructed using the Bayesian inference (BI) method in MrBayes 3.2.7a software. The differences in the ITS2 secondary structure between the species were analyzed.ResultsThe success rate of PCR amplification and sequencing was 75% and 67%, respectively. The analyzed ITS2 sequences displayed significant inter-specific divergences, clear DNA barcoding gaps and high species identification efficiency. Based on the constructed phylogenetic tree, three Physalis species (Physalis peruviana, Physalis purpurea and Physalis cordata) were identified and were clustered in a homogenized distribution. High genetic diversity (0.36923) and genetic distance (0.703) were observed between Physalis peruviana and Physalis cordata. The highest genetic nucleotide diversity (0.26324) and distance (0.46) within species was obtained for Physalis peruviana. The differences in the secondary structures generated from this study discriminated between the Physalis species.ConclusionsOur study demonstrated that ITS2 is a potential DNA barcode for effective identification and discrimination of Physalis species. The results of this study provide insights into the scientific basis of species identification, safe utilization, genetic conservation and future breeding strategies for this important nutritional and medicinal plant species.

Single-cell analysis of a bi-clonal chronic lymphocytic leukemia reveals two clones with distinct gene expression pattern

Dual productive B-cell receptor (BCR) rearrangements have been repeatedly reported for chronic lymphocytic leukemia (CLL), but the standard population-based PCR analyses cannot distinguish whether these are bi-clonal CLL, or a monoclonal CLL with bi-allelic productive rearrangements. We investigated CLL cells by combined single-cell RNA and BCR sequencing. We identified two CLL clones using different immunoglobulin (Ig) heavy-chain V region genes (IGHV) genes and distinct Ig λ light chains. One clone is classified as Ig unmutated the other as mutated. The two CLL clones have distinct transcriptomes: Numerous genes were differentially expressed, with genes typical for unmutated or mutated CLL showing the expected representation in the two clones. Using PCR, cloning and Sanger sequencing of the IGHV rearrangements we detected both CLL clones over a period of three years without clinical progression of the CLL and thus giving insights into the disease biology of multi-clonal CLL.

Pathogenesis of acephalic spermatozoa syndrome caused by PMFBP1 mutation

BackgroundAcephalic spermatozoa syndrome is a rare but severe type of teratozoospermia. The familial trait of acephalic spermatozoa syndrome suggests that genetic factors play an important role. However, known mutations account for only some acephalic spermatozoa syndrome patients, and more studies are needed to elucidate its pathogenesis. The current study aimed to elucidate the pathogenesis of acephalic spermatozoa syndrome caused by PMFBP1 mutation.ResultsWe identified a homozygous splice site mutation (NM_031293.2, c.2089-1G > T) in PMFBP1 through Sanger sequencing. Western blotting and immunofluorescence analyses revealed that this splice site mutation resulted in the absence of PMFBP1 protein expression in the patient's sperm cells. We generated an in vitro model carrying the splice site mutation in PMFBP1 and confirmed, through RT‒PCR and Sanger sequencing, that it led to a deletion of 4 base pairs from exon 15.ConclusionA homozygous splice site mutation results in a deletion of 4 bp from exon 15 of PMFBP1, thereby affecting the expression of the PMFBP1 protein. The absence of PMFBP1 protein expression can lead to acephalic spermatozoa syndrome. This finding elucidates the underlying cause of acephalic spermatozoa syndrome associated with this specific mutation (NM_031293.2, c.2089-1G > T) in PMFBP1.

Automatic identification of clinically important Aspergillus species by artificial intelligence-based image recognition: proof-of-concept study

ABSTRACT While morphological examination is the most widely used for Aspergillus identification in clinical laboratories, PCR–sequencing and MALDI–TOF MS are emerging technologies in more financially-competent laboratories. However, mycological expertise, molecular biologists and/or expensive equipment are needed for these. Recently, artificial intelligence (AI), especially image recognition, is being increasingly employed in medicine for fast and automated disease diagnosis. We explored the potential utility of AI in identifying Aspergillus species. In this proof-of-concept study, using 2813, 2814 and 1240 images from four clinically important Aspergillus species for training, validation and testing, respectively; the performances and accuracies of automatic Aspergillus identification using colonial images by three different convolutional neural networks were evaluated. Results demonstrated that ResNet-18 outperformed Inception-v3 and DenseNet-121 and is the best algorithm of choice because it made the fewest misidentifications (n = 8) and possessed the highest testing accuracy (99.35%). Images showing more unique morphological features were more accurately identified. AI-based image recognition using colonial images is a promising technology for Aspergillus identification. Given its short turn-around-time, minimal demand of expertise, low reagent/equipment costs and user-friendliness, it has the potential to serve as a routine laboratory diagnostic tool after the database is further expanded.

Free-Ranging Wolves (Canis lupus) are Natural Reservoirs of Intestinal Microeukaryotes of Public Health Significance in Southwestern Europe.

Intestinal microeukaryote parasites are major contributors to the burden of diarrhoea in humans and domestic animals, but their epidemiology in wildlife is not fully understood. We investigated the frequency, genetic diversity and zoonotic potential of protists of animal and public health significance in free-ranging grey wolf (Canis lupus) populations in south-western Europe. Individually formed faecal samples collected from necropsied wolves or scat trails in Italy (n = 47), Portugal (n = 43) and Spain (n = 225) during the period 2011-2023 were retrospectively analysed using molecular (PCR and Sanger sequencing) methods. Complementary epidemiological data were gathered when available. Giardia duodenalis was the most frequent microeukaryote found (40.3%, 127/315; 95% CI: 34.9-46.0), followed by Cryptosporidium spp. (3.5%, 11/315; 95% CI: 1.8-6.2), Enterocytozoon bieneusi and Encephalitozoon spp. (1.6%, 5/315; 95% CI: 0.5-3.7 each). Blastocystis was not identified in any of the faecal samples analysed. Sequence analyses confirmed the presence of canine-adapted assemblage D within G. duodenalis (n = 7). Three Cryptosporidium species were identified, namely canine-adapted C. canis (n = 9), zoonotic C. parvum (n = 1) and primarily anthroponotic C.hominis (n = 1). Genotyping tools enabled the identification of subtype family XXe2 within C. canis. Among microsporidia, the canine-adapted genotype PtEb IX was identified within E. bieneusi. Two samples were confirmed as Enc. intestinalis and three more as Enc. cuniculi genotype IV. This is the first record of Enc. intestinalis and Enc. cuniculi in the grey wolf globally. Silent carriage of intestinal microeukaryotes seems common in free-ranging grey wolves in southwestern Europe. Wolves can contribute to environmental contamination through the transmission stages (cysts, oocysts, spores) of species/genotypes potentially infective to humans. Individuals in close contact with wolf carcasses or their faecal material may be at potential risk of infection by microeukaryotic pathogens.

Lysyl Oxidase Mediates Proliferation and Differentiation in the Esophageal Epithelium

In homeostatic conditions, the basal progenitor cells of the esophagus differentiate into a stratified squamous epithelium. However, in the setting of acid exposure or inflammation, there is a marked failure of basal cell differentiation, leading to basal cell hyperplasia. We have previously shown that lysyl oxidase (LOX), a collagen crosslinking enzyme, is upregulated in the setting of allergic inflammation of the esophagus; however, its role beyond collagen crosslinking is unknown. Herein, we propose a non-canonical epithelial-specific role of LOX in the maintenance of epithelial homeostasis using 3D organoid and murine models. We performed quantitative reverse transcriptase PCR, Western blot, histologic analysis, and RNA sequencing on immortalized non-transformed human esophageal epithelial cells (EPC2-hTERT) with short-hairpin RNA (shRNA) targeting LOX mRNA in both monolayer and 3D organoid culture. A novel murine model with a tamoxifen-induced Lox knockout specific to the stratified epithelium (K5CreER; Loxfl/fl) was utilized to further define the role of epithelial LOX in vivo. We found that LOX knockdown decreased the proliferative capacity of the esophageal epithelial cells in monolayer culture, and dramatically reduced the organoid formation rate (OFR) in the shLOX organoids. LOX knockdown was associated with decreased expression of the differentiation markers filaggrin, loricrin, and involucrin, with RNA sequencing analysis revealing 1224 differentially expressed genes demonstrating downregulation of pathways involved in cell differentiation and epithelial development. Mice with Lox knockout in their stratified epithelium demonstrated increased basaloid content of their esophageal epithelium and decreased Ki-67 staining compared to the vehicle-treated mice, suggesting reduced differentiation and proliferation in the Lox-deficient epithelium in vivo. Our results demonstrate, both in vivo and in vitro, that LOX may regulate epithelial homeostasis in the esophagus through the modulation of epithelial proliferation and differentiation. Understanding the mechanisms of perturbation in epithelial proliferation and differentiation in an inflamed esophagus could lead to the development of novel treatments that could promote epithelial healing and restore homeostasis.

18S rRNA Metagenomic Analysis of Nodular Gill Disease in Swiss Rainbow Trout (Oncorhynchus mykiss).

Nodular gill disease (NGD) is a serious proliferative gill condition that affects farmed salmonids, particularly in Europe. While the cause of NGD remains unknown (and maybe multifactorial), various amoebae are often isolated from the gills of affected fish and can in some cases be seen associated with lesions by histopathology. The present study aimed to quantify the abundance of different amoeba species directly from the gills of rainbow trout affected by NGD and healthy controls. An 18S rRNA amplicon metagenomic approach was employed to profile the diversity and abundance of micro-eukaryotes (including amoebae) while suppressing the amplification of host DNA using a salmonid-specific C3 spacer blocking primer. The 18S rRNA metagenomics approach identified a diversity of micro-eukaryotes on the gills of rainbow trout, including the phylum's Amoebozoa, Diatomea, Platyhelminthes and Ciliophora. Rainbow trout clinically affected by NGD had a significantly higher abundance of a specific sequence (zOTU2) classified as Vannella sp. compared to healthy controls. A quantitative PCR assay was then developed and validated which accurately quantified the abundance of this Vannella sp. sequence from a NGD outbreak in a Swiss rainbow trout farm. Additional PCR and Sanger sequencing analysis of the zOTU2 sequence demonstrated that this sequence is most likely derived from Vannella mustalahtiana. Our study highlights the potential role of Vannella mustalahtiana in NGD in Switzerland and further describes a specific and validated diagnostic PCR assay for accurate detection of this Vannella species.

Distribution of HPV Types in Cervical Cancer in Pakistan: Implications for Screening and Vaccination Programs.

HPV plays a key role in the development of cervical cancer. This study aims to investigate the prevalence of HPV genotypes in patients with Squamous cell carcinoma (SSC) and Adenocarcinoma (ADC) at NORI cancer Hospital Pakistan, with the aim of improving screening and prevention strategies. Cervical scrapings were collected from 129 diagnosed cervical cancer patients. HPV typing was performed using a real-time PCR assay and sequencing. Among the patients, 73.6% (90/129) were HPV positive. Proportion of HPV positivity was observed within each group. The highest incidence of HPV was observed in the 50-60 years age group (80.9%), followed by the 40-to-50-year group (75.8%). The positivity rate declined in the 60-to-70-year-old (63.6%) and further in the 70-80 years (62.5%). Eight different HPV subtypes were identified, with HPV 16 being the most prevalent (80.0%), followed by HPV 18 (9.5%), HPV 45 in 2 (2.1%), HPV 31 in 1 (1.1%), HPV 35 in 1 (1.1%), HPV 59 in 1 (1.1%), HPV 66 in 1 (1.1%), and HPV 89 in 1 (1.15). Histologically, 89.2% of the cases were Squamous cell carcinoma (SCC) and 10.8% were Adenocarcinomas. In SCC patients, HPV 16 was found in 80.9% of cases, while in Adenocarcinoma patients, HPV 16 was detected in 66.7% of cases. The prevalence of high-risk HPV types, both vaccine and non-vaccine, targeted in Pakistan highlights the urgent need for widespread screening and vaccination programs. Tailored public health strategies are essential to effectively reduce cervical cancer rates and mortality.

Molecular surveillance and antimicrobial susceptibility profile of bacterial contamination in pastries of Iranian confectioneries: a public health concern.

Microbial contamination in food products such as pastries, poses a significant public health concern due to the potential risks of foodborne infection and outbreak, Therefore, to prevent these infections, it is essential to investigate the frequency and extent of microbial contamination as well as the level of drug resistance in pastries. Due to this issue, our study aimed to assess the microbial diversity and the drug susceptibility patterns of microbial pollutants in pastry shops in Markazi province, Iran. The study involved collecting 120 pastry samples from 30 pastry shops in Markazi province, Iran. The isolates were identified using a series of biochemical, phenotypic, and molecular assays, including specific PCR and 16S rRNA gene sequencing. Drug susceptibility testing (AST) was performed by using the Kirby-Bauer method according to the CLSI 2023 guidelines. A total of 56 isolates (46.66%) were recovered from 120 pastries samples, The most prevalent species isolated in the current study were S. aureus 12 isolates (21.43%), M. luteus 7 isolates (12.5%), E. coli 7 isolates (12.5%), S. warneri 6 isolates (11.12%), 6 isolates of S. succinus (11.12%), B. cereus 5 isolates (10.7%), Nocardia 4 isolates (7.15%), K. pneumoniae 3 isolates (5.35%), S. epidermidis 3 isolates (5.35%), and E. faecium 3 isolates (5.35%). The isolates showed the most sensitivity to imipenem and trimethoprim-sulfamethoxazole and the least sensitivity to erythromycin and tetracycline. The AST showed that 7 isolates of S. aureus were MRSA, 3 isolates of E. coli and, 2 isolates of K. pneumoniae were identified as ESBL. In conclusion, the results of the current study showed that the microbial contamination of pastries produced in confectionaries of Markazi province was not in standard ranges. These problems may be related to fecal contamination of pastries or lack of hygiene by handlers and it is urgent to develop the standards of hygiene of food handling techniques and aseptic pastry production in confectioneries.

MiR-198 targets TOPORS: implications for oral squamous cell carcinoma pathogenesis.

miRNAs play a critical role in the progression of various diseases, including oral squamous cell carcinoma (OSCC), which represents a major health concern and is one of the leading causes for new cancer cases worldwide. The miRNA dysregulation causes havoc and could be attributed to various factors, with epigenetic silencing of tumor suppressor genes being a major contributor to tumorigenesis. In this study, we have explored the tumor suppressive role of miR-198 in OSCC. The tumor suppressive effect of miR-198 is established using miRNA analysis in OSCC cell lines, patient samples and xenograft nude mice model. The relationship between the miR-198 and TOPORS is explored using bioinformatics analyses, qRT-PCR, dual-luciferase reporter assay, Western blotting and cancer hall marks assays. The hypermethylation of the MIR198 promoter is confirmed using bisulfite sequencing PCR. We have found miR-198 to be upregulated in OSCC cells treated with 5-Azacytidine, a known DNA methyltransferase inhibitor. Upregulation of miR-198 in 5-Azacytidine treated OSCC cells appears to be due to methylation of the MIR198 promoter. Using bioinformatics analysis and dual-luciferase reporter assay, we have identified TOPORS (TOP1 binding arginine/serine rich protein, E3 ubiquitin ligase) as a novel gene target for miR-198. miR-198-mediated repression of TOPORS decreases cell proliferation and anchorage-independent growth and enhances apoptosis of OSCC cells, which is dependent on the presence of the 3'UTR in TOPORS. An inverse correlation between the expression levels of miR-198 and TOPORS is observed in OSCC patient samples, highlighting the biological relevance of their interaction. Delivery of a synthetic miR-198 mimic to OSCC cells results in a significant decrease in xenograft size in nude mice, potentiating its use in therapeutics. These results suggest that miR-198 is epigenetically silenced in OSCC, which promotes tumor growth, in part, by upregulating the levels of TOPORS.

Dynamics of rice seed-borne bacteria from acquisition to seedling colonization

BackgroundRice cultivation relies on planting grains harboring beneficial microbiota. However, the origination, distribution, and transmission dynamics of grain-borne bacteria remain unclear.ResultsUsing rice grain as a model system, this study investigates the primary sources, major niches in seeds, and the dynamics of community acquisition, maintenance, and transmission between generations of grain-borne bacteria. Quantitative PCR and 16S rRNA gene sequencing demonstrate rice grains acquiring bacteria primarily from the external environment during panicle heading and flowering. These bacteria concentrate between the caryopsis and glumes, establishing sizable communities in developing seeds. The dominant taxa included Pantoea, Pseudomonas, and Sphingomonas. Throughout seed development and storage, community structure remains consistent while abundance fluctuates within one order of magnitude. Upon germination under axenic conditions, seed bacteria successfully colonize shoots and roots of offspring seedlings. However, bacteria transmitted solely through internal routes fail to form comparably large communities. Analysis of taxonomic composition uncovers dramatic reshaping from seeds to seedlings, potentially reflecting functional adaptation.ConclusionsWe clarify seed-borne bacterial origination, acquisition timing, seed colonization, intergenerational transmission, and seedling diversification. Our findings provide novel insights into rice seed bacterial dynamics critical for microbiome management.9FJ-hzomPrM-V3Zi4Nmp4KVideo

Cultivation and molecular characterization of viable Helicobacter pylori from the root canal of 170 deciduous teeth of children

BackgroundHelicobacter pylori is a persistent pathogen in the human stomach. However, the proposed transmission route via the oral cavity is not understood and under intense debate. While dozens of studies have shown by PCR that H. pylori DNA is frequently present in the oral cavity, data on the growth and characterization of viable H. pylori from this compartment are very scarce, and it is unclear whether the bacteria can survive in the oral cavity for longer time periods or even colonize it.MethodsSelective growth methods, scanning electron microscopy, urease assay, Western blotting, PCR, and gene sequencing were applied to identify and examine viable H. pylori in decayed milk teeth.ResultsHere, we studied viable H. pylori in the plaque and root canals of 170 endodontically infected deciduous teeth that were extracted from 54 children. While H. pylori DNA was detected in several plaque and many root canal samples by PCR, live bacteria could only be cultivated from 28 root canals, but not from plaque. These 28 isolates have been identified as H. pylori by PCR and sequencing of vacA, cagA and htrA genes, phylogenetic analyses, protein expression of major H. pylori virulence factors, and by signal transduction events during infection of human cell lines.ConclusionsThus, the microaerobic environment in the root canals of endodontically infected teeth may represent a protected and transient reservoir for live H. pylori, especially in individuals with poor dental hygiene, which could serve as a potential source for re-infection of the stomach after antibiotic therapy or for transmission to other individuals.

Resistome in the indoor dust samples from workplaces and households: a pilot study.

The antibiotic resistance genes (ARGs) limit the susceptibility of bacteria to antimicrobials, representing a problem of high importance. Current research on the presence of ARGs in microorganisms focuses mainly on humans, livestock, hospitals, or wastewater. However, the spectrum of ARGs in the dust resistome in workplaces and households has gone relatively unexplored. This pilot study aimed to analyze resistome in indoor dust samples from participants' workplaces (a pediatric hospital, a maternity hospital, and a research center) and households and compare two different approaches to the ARGs analysis; high-throughput quantitative PCR (HT-qPCR) and whole metagenome shotgun sequencing (WMGS). In total, 143 ARGs were detected using HT-qPCR, with ARGs associated with the macrolides, lincosamides, and streptogramin B (MLSB) phenotype being the most abundant, followed by MDR (multi-drug resistance) genes, and genes conferring resistance to aminoglycosides. A higher overall relative quantity of ARGs was observed in indoor dust samples from workplaces than from households, with the pediatric hospital being associated with the highest relative quantity of ARGs. WMGS analysis revealed 36 ARGs, of which five were detected by both HT-qPCR and WMGS techniques. Accordingly, the efficacy of the WMGS approach to detect ARGs was lower than that of HT-qPCR. In summary, our pilot data revealed that indoor dust in buildings where people spend most of their time (workplaces, households) can be a significant source of antimicrobial-resistant microorganisms, which may potentially pose a health risk to both humans and animals.

Long-term therapeutic efficacy and safety profiles of hpCas13d RNA editing in treating early-onset hypertrophic cardiomyopathy

AimsThrough evolving a precise RNA nuclease, hpCas13d, we have successfully inhibited hypertrophic cardiomyopathy in a compound heterozygous model. However, further investigation is needed to assess the long-term therapeutic effects and safety profiles of hpCas13d treatment. Materials and methodsAAV-hpCas13d[RQ] was subcutaneously injected into neonatal Myh6RH/RQ mice. Sequential echocardiography analyses were conducted at 4 months and 12 months to evaluate the sustained therapeutic effects of hpCas13d. Electrocardiography was employed to assess cardiac arrhythmias, and mice were euthanized at 12 months. Quantification of Myh6RQ degradation induced by hpCas13d[RQ] was performed using digital droplet PCR and cDNA sequencing. Histological analysis, RNA sequencing, and proteomic analyses were utilized to examine the inhibitory effects on pathological phenotypes and downstream signaling pathways. Biodistribution, tissue damage, and host immune response to AAV-hpCas13d[RQ] were assessed to evaluate long-term safety profiles. Key findingsThe allele-specific RNA degradation persisted for 12 months in AAV-hpCas13d[RQ]-treated Myh6RH/RQ mice. Partial degradation of pathogenic Myh6RQ transcripts proved adequate for the long-term inhibition of cardiac hypertrophy, arrhythmias, fibrosis, and cellular apoptosis in Myh6RH/RQ mice. RNA sequencing and proteomic analyses revealed that hpCas13d[RQ] treatment impeded hypertrophy and fibrosis, mitochondrial dysfunction, and abnormalities in ion channels downstream of mutant Myh6. Prolonged treatment with AAV-hpCas13d from the neonatal stage did not induce significant tissue damage, liver toxicity, humoral responses, or cellular immune reactions against the AAV9 capsid and bacterial hpCas13d. SignificanceThese results underscore the promising translational potential of AAV-hpCas13d in treating cardiovascular diseases and advancing in vivo gene therapy.

Bioconversion of sulfamethazine-contaminated chicken manure by black soldier fly larvae: Effects on antibiotic resistance genes and microbial communities.

Sulfamethazine (SM2), a widely detected antibiotic in livestock manure, poses environmental and health risks due to its persistence and the proliferation of antibiotic resistance genes (ARGs). In this study, we investigated the degradation of SM2 and the elimination of sulfonamide ARGs (sul1 and sul2) in chicken manure contaminated with varying concentration of SM2 by black soldier fly larvae (BSFL). Quantitative PCR and 16S rRNA gene sequencing were employed to monitor changes in sulfa ARGs and microbial community composition within both the larvae gut and chicken manure. During the 12-day test period, BSFL exhibited strong tolerance to SM2, significantly reducing SM2 concentrations by 80.54%-92.22% across different treatment groups. Concurrently, the abundance of sul1 and sul2 decreased by 79.27% and 79.92% in chicken manure, respectively. Additionally, microbial genera such as Firmicutes (47.18-65%) and Bacillus (9.32-10.25%), which were enriched in both the BSFL gut and chicken manure, were identified as potential contributors to SM2 degradation. These findings provide a promising biotechnological strategy for mitigating antibiotic contamination in livestock manure.

Top-down predators shape soil bacterial community composition while bottom-up nutrients drive bacterial abundance

Although the top-down and bottom-up concept in microbial food-webs has been a primary interest in ecology, less is still known about it in soil ecosystems. Protists are the primary top-down predators of bacterial communities, altering their compositions, while the bottom-up resources are the primary factors limiting bacterial growth. Here, we hypothesized that the top-down predators modulate soil bacterial community composition, while the bottom-up nutrients control the bacterial growth and population. To precisely control nutrient levels, we used an inert soil substitute consisting of a combination of calcined clay and sand. Nutrients equivalent to the reference paddy field soil were added to microcosms as a control treatment. To investigate the effects of C, N, and P, six additional bottom-up treatments in the absence and double amounts of the nutrients were prepared. Four top-down treatments (no protist addition, Acanthamoeba castellanii, Vermamoeba vermiformis, and Heteromita globosa) were set up for each bottom-up treatment. A total of 252 microcosms under 28 treatments were incubated. Bacterial communities were analyzed using high-throughput sequencing and real-time PCR in the 1st, 3rd, and 5th weeks. The results revealed that the top-down predators significantly altered the bacterial community composition, and the bacterial population was predominantly controlled by the bottom-up nutrients. Analysis of absolute abundance data demonstrated that both top-down and bottom-up factors shaped the bacterial community structure (community composition and population). Random forest analysis classified the amplicon sequence variants associated with the treatments, showing that mostly similar families were affected by both bottom-up and top-down factors. In conclusion, the results of this study fully supported our hypothesis that top-down predators alter community composition, while bottom-up factors influence bacterial population dynamics.

Asperosaponin VI inhibition of DNMT alleviates GPX4 suppression-mediated osteoblast ferroptosis and diabetic osteoporosis.

Diabetic osteoporosis (DOP) is an insidious complication of diabetes with limited therapeutic options. DOP is pathologically associated with various types of regulated cell death, but the precise role of ferroptosis in the process remains poorly understood. Asperosaponin VI (AVI), known for its clinical efficacy in treating bone fractures and osteoporosis, may exert its osteoprotective effects through mechanisms involving ferroptosis, however this has not been established. This study aimed to investigate the role of AVI in modulating ferroptosis in a mouse model of DOP and to explore the underlying mechanisms. We assessed OP alterations in femurs of DOP-conditioned mice and primary bone cells. We generated a strain of osteoblast-specific Gpx4-deficient mice. A combination of micro-CT, immunohistochemistry, immunofluorescence, methylation-specific PCR (MSP), bisulfite sequencing PCR (BSP), western blotting (WB), and AVI pull-down assays were employed to elucidate the mechanism and therapeutic target of AVI in DOP. Our findings revealed that femurs from DOP-conditioned mice exhibited significant ferroptosis and suppression of the core anti-ferroptosis factor GPX4, mainly due to hypermethylation of the Gpx4 promoter mediated by DNA methyltransferases DNMT1and DNMT3a. Notably, treatment with AVI effectively reversed the hypermethylation, restored GPX4 expression, and reduced ferroptotic pathologies associated with DOP by inhibiting DNMT1/3a. In primary osteoblasts, AVI alleviated GPX4 suppression and reduced ferroptosis in DOP-conditioned primary osteoblasts through a mechanism dependent on DNMT inhibition and GPX4 restoration. Importantly, the anti-ferroptotic and osteoprotective effects of AVI were abolished in osteoblastic Gpx4 haplo-deficient mice (Gpx4Ob-/+) or when GPX4 was pharmacologically inactivated with RSL3. Our study identifies a pivotal epigenetic ferroptotic pathway that contributes significantly to DOP and uncovers a crucial pharmacological property of AVI that is potentially effective in treating patients with DOP and related osteoporotic disorders.

N6-methyladenosine (m6A)-circHECA from secondary hair follicle of cashmere goats: identification, regulatory network and expression regulated potentially by methylation of its host gene promoter.

The objective of this study was to identify the N6-methyladenosine (m6A)- circHECA molecule in secondary hair follicles (SHFs) of cashmere goats, and generate its potential regulatory network, as well as explore the potential relationship between transcriptional pattern of m6A-circHECA and promoter methylation of its host gene (HECA). The validation of circHECA m6A sites was performed using methylation immunoprecipitation (Me-RIP) along with reverse transcription-quantitative polymerase chain reaction (RT-qPCR) technique. The nucleus and cytoplasm localizations of m6AcircHECA were performed using SHF stem cells of cashmere goats with RT-qPCR analysis. Based on in-silico analysis, the regulatory networks of m6A-circHECA were generated with related signal pathway enrichment. The methylation level of promoter region of m6A-circHECA host gene (HECA) was assessed by the bisulfite sequencing PCR (BSPPCR) technique. The m6A-circHECA was confirmed to contain four m6A modification sites including m6A-213, m6A-297, m6A-780, and m6A-927, and it was detected mainly in cytoplasm of the SHF stem cells of cashmere goats. The integrated regulatory network analysis showed directly or indirectly complex regulatory relationships between m6A-circHECA of cashmere goats and its potential target molecules: miRNAs, mRNAs, and proteins. The regulatory network and pathway enrichment indicated that m6A-circHECA might play multiple roles in the SHF physiology process of cashmere goats through directly or indirectly interacting or regulating its potential target molecules. A higher methylation level of promoter region of HECA gene in SHFs of cashmere goats might cause the lower expression of m6A-circHECA. The m6A-circHECA might play multiple roles in SHF physiology process of cashmere goats through miRNA mediated pathways along with directly or indirectly interaction with its target proteins. The promoter methylation of m6A-circHECA host gene (HECA) most likely was implicated in its expression inhibition in SHFs of cashmere goats.