RESUMO
BACKGROUND: Benign prostatic hyperplasia (BPH) is a prevalent disease affecting elderly men, with chronic inflammation being a critical factor in its development. Omentin-1, also known as intelectin-1 (ITLN-1), is an anti-inflammatory protein primarily found in the epithelial cells of the small intestine. This study aimed to investigate the potential of ITLN-1 in mitigating BPH by modulating local inflammation in the prostate gland. METHODS: Our investigation involved two in vivo experimental models. Firstly, ITLN-1 knockout mice (Itln-1-/-) were used to study the absence of ITLN-1 in BPH development. Secondly, a testosterone propionate (TP)-induced BPH mouse model was treated with an ITLN-1 overexpressing adenovirus. We assessed BPH severity using prostate weight index and histological analysis, including H&E staining, immunohistochemistry, and enzyme-linked immunosorbent assay. In vitro, the impact of ITLN-1 on BPH-1 cell proliferation and inflammatory response was evaluated using cell proliferation assays and enzyme-linked immunosorbent assay. RESULTS: In vivo, Itln-1-/- mice exhibited elevated prostate weight index, enlarged lumen area, and higher TNF-α levels compared to wild-type littermates. In contrast, ITLN-1 overexpression in TP-induced BPH mice resulted in reduced prostate weight index, lumen area, and TNF-α levels. In vitro studies indicated that ITLN-1 suppressed the proliferation of prostate epithelial cells and reduced TNF-α production in macrophages, suggesting a mechanism involving the inhibition of macrophage-mediated inflammation. CONCLUSION: The study demonstrates that ITLN-1 plays a significant role in inhibiting the development of BPH by reducing local inflammation in the prostate gland. These findings highlight the potential of ITLN-1 as a therapeutic target in the management of BPH.
Assuntos
Proteínas Ligadas por GPI , Lectinas , Hiperplasia Prostática , Animais , Masculino , Camundongos , Citocinas/genética , Citocinas/metabolismo , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/metabolismo , Inflamação/patologia , Lectinas/genética , Lectinas/metabolismo , Extratos Vegetais/farmacologia , Próstata/metabolismo , Próstata/patologia , Hiperplasia Prostática/genética , Hiperplasia Prostática/tratamento farmacológico , Hiperplasia Prostática/metabolismo , Fator de Necrose Tumoral alfaRESUMO
African swine fever virus (ASFV) is a large DNA virus that causes African swine fever (ASF), an acute and hemorrhagic disease in pigs with lethality rates of up to 100%. To date, how ASFV efficiently suppress the innate immune response remains enigmatic. In this study, we identified ASFV cysteine protease pS273R as an antagonist of type I interferon (IFN). Overexpression of pS273R inhibited JAK-STAT signaling triggered by type I IFNs. Mechanistically, pS273R interacted with STAT2 and recruited the E3 ubiquitin ligase DCST1, resulting in K48-linked polyubiquitination at K55 of STAT2 and subsequent proteasome-dependent degradation of STAT2. Furthermore, such a function of pS273R in JAK-STAT signaling is not dependent on its protease activity. These findings suggest that ASFV pS273R is important to evade host innate immunity. IMPORTANCE ASF is an acute disease in domestic pigs caused by infection with ASFV. ASF has become a global threat with devastating economic and ecological consequences. To date, there are no commercially available, safe, and efficacious vaccines to prevent ASFV infection. ASFV has evolved a series of strategies to evade host immune responses, facilitating its replication and transmission. Therefore, understanding the immune evasion mechanism of ASFV is helpful for the development of prevention and control measures for ASF. Here, we identified ASFV cysteine protease pS273R as an antagonist of type I IFNs. ASFV pS273R interacted with STAT2 and mediated degradation of STAT2, a transcription factor downstream of type I IFNs that is responsible for induction of various IFN-stimulated genes. pS273R recruited the E3 ubiquitin ligase DCST1 to enhance K48-linked polyubiquitination of STAT2 at K55 in a manner independent of its protease activity. These findings suggest that pS273R is important for ASFV to escape host innate immunity, which sheds new light on the mechanisms of ASFV immune evasion.
Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Cisteína Proteases , Interferon Tipo I , Animais , Cisteína Proteases/genética , Cisteína Proteases/metabolismo , Imunidade Inata/genética , Interferon Tipo I/metabolismo , Sus scrofa , Suínos , Ubiquitina-Proteína Ligases/metabolismo , Fator de Transcrição STAT2/metabolismo , Transdução de SinaisRESUMO
BACKGROUND: Bone marrow mesenchymal stem cells (BMSCs) can undergo inadequate osteogenesis or excessive adipogenesis as they age due to changes in the bone microenvironment, ultimately resulting in decreased bone density and elevated risk of fractures in senile osteoporosis. This study aims to investigate the effects of osteocyte senescence on the bone microenvironment and its influence on BMSCs during aging. RESULTS: Primary osteocytes were isolated from 2-month-old and 16-month-old mice to obtain young osteocyte-derived extracellular vesicles (YO-EVs) and senescent osteocyte-derived EVs (SO-EVs), respectively. YO-EVs were found to significantly increase alkaline phosphatase activity, mineralization deposition, and the expression of osteogenesis-related genes in BMSCs, while SO-EVs promoted BMSC adipogenesis. Neither YO-EVs nor SO-EVs exerted an effect on the osteoclastogenesis of primary macrophages/monocytes. Our constructed transgenic mice, designed to trace osteocyte-derived EV distribution, revealed abundant osteocyte-derived EVs embedded in the bone matrix. Moreover, mature osteoclasts were found to release osteocyte-derived EVs from bone slices, playing a pivotal role in regulating the functions of the surrounding culture medium. Following intravenous injection into young and elderly mouse models, YO-EVs demonstrated a significant enhancement of bone mass and biomechanical strength compared to SO-EVs. Immunostaining of bone sections revealed that YO-EV treatment augmented the number of osteoblasts on the bone surface, while SO-EV treatment promoted adipocyte formation in the bone marrow. Proteomics analysis of YO-EVs and SO-EVs showed that tropomyosin-1 (TPM1) was enriched in YO-EVs, which increased the matrix stiffness of BMSCs, consequently promoting osteogenesis. Specifically, the siRNA-mediated depletion of Tpm1 eliminated pro-osteogenic activity of YO-EVs both in vitro and in vivo. CONCLUSIONS: Our findings suggested that YO-EVs played a crucial role in maintaining the balance between bone resorption and formation, and their pro-osteogenic activity declining with aging. Therefore, YO-EVs and the delivered TPM1 hold potential as therapeutic targets for senile osteoporosis.
Assuntos
Vesículas Extracelulares , Células-Tronco Mesenquimais , Osteócitos , Osteogênese , Tropomiosina , Animais , Masculino , Camundongos , Adipogenia , Diferenciação Celular , Células Cultivadas , Vesículas Extracelulares/metabolismo , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/citologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Osteoclastos/metabolismo , Osteócitos/metabolismo , Osteoporose/metabolismo , Tropomiosina/metabolismo , Tropomiosina/genéticaRESUMO
Aiming to determine the scattered estimation of complex and electrically large targets coated with the uniaxial electric anisotropic medium (UEAM) from a distributed excitation source, the demanding study is simplified by constructing the physical optics (PO) architecture which consists of three aspects, the discrete facet modeling, the tangent plane approximation, and the scattering of an infinite PEC plate coated with the UEAM based on point-source excitation, including the electric and magnetic dipole. We depict the outer surface of an electrically large scatterer as the constitution of countless tiny triangular facets. From the tangent plane approximation employed in the PO method, the scattered fields of any discretized facet induced by the equivalent electromagnetic currents (EECs) can be further evaluated as the surface fields of an infinite UEAM-coated PEC slab. Therefore, the rigorous solution of the dyadic Green's function (DGFs) for an infinite anisotropic-medium-coated PEC plate under point-source incidence is computed first. Moreover, characterizing the ray propagation process of the plane wave spectrum, the asymptotic technique of the saddle point is employed to obtain the scattered ray field in the spatial domain. Finally, the total scattered fields are obtained by the field superposition of the overall illuminated facets under point-source excitation. Compared with the reference solution, the proposed method is validated, and the simulation results of the representative shapes coated with the UEAM layer from a point source are presented.
RESUMO
Salmonella Enteritidis (SE) can be transmitted to eggs through cecum or the ovary from infected layers and causes food poisoning in humans. The mechanism of cecal transmission has been extensively studied. However, the mechanism and route of transovarian transmission of SE remain unclear. In this study, the ducks were orally inoculated with SE, and the ovarian follicles and stroma were collected to detect SE infection. The immune responses were triggered and the innate and adaptive immune genes (TLR4, NOD1, AvßD7, and IL-1ß) were upregulated significantly during the SE challenge. Moreover, the ovary tissues (small follicle and stroma) of susceptible and resistant-laying ducks were performed by RNA sequencing. We obtained and identified 23 differentially expressed genes (DEGs) between susceptible and resistant-laying ducks in both small follicle and stroma tissues ( p < 0.05). The DEGs were predominately identified in the p53 signaling pathway. The expression of key genes (p53, MDM2, PERP, caspase-3, and Bcl-2) involved in the signaling pathway was significantly higher in granulosa cells (dGCs) from SE-infected ducks than those from uninfected ducks. Moreover, the overexpression of PERP resulted in further induction of p53, MDM2, caspase-3, and Bcl-2 during SE infection in dGCs. Whereas, an opposite trend was observed with the knockdown of PERP. Besides, it is further revealed that the PERP could enhance cell apoptosis, SE adhesion, and SE invasion in SE-infected dGCs overexpression. Altogether, our results demonstrate the duck PERP involved in the ovarian local immune niche through p53 signaling pathway in dGCs challenged with SE.
Assuntos
Patos/imunologia , Patos/microbiologia , Perfilação da Expressão Gênica/veterinária , Células da Granulosa/metabolismo , Proteínas de Membrana/metabolismo , Salmonelose Animal/imunologia , Animais , Apoptose/fisiologia , Proliferação de Células/fisiologia , Feminino , Regulação da Expressão Gênica/genética , Proteínas de Membrana/genética , Proteínas de Membrana/imunologia , Folículo Ovariano/imunologia , Folículo Ovariano/microbiologia , Salmonelose Animal/microbiologia , Salmonelose Animal/patologia , Salmonella enteritidis/imunologia , Proteína Supressora de Tumor p53/metabolismoRESUMO
BACKGROUND: Taenia hydatigena, T. multiceps, T. pisiformis, and Dipylidium caninum are four common large and medium-sized tapeworms parasitizing the small intestine of dogs and other canids. These parasites cause serious impact on the health and development of livestock. However, there are, so far, no commercially available molecular diagnostic kits capable of simultaneously detecting all four parasites in dogs. The aim of the study was therefore to develop a multiplex PCR assay that will accurately detect all four cestode infections in one reaction. METHODS: Specific primers for a multiplex PCR were designed based on corresponding mitochondrial genome sequences, and its detection limit was assessed by serial dilutions of the genomic DNAs of tapeworms examined. Furthermore, field samples of dog feces were tested using the developed assay. RESULTS: A multiplex polymerase chain reaction (PCR) assay was developed based on mitochondrial DNA (mtDNA) that accurately and simultaneously identify four cestode species in one reaction using specific fragment sizes of 592, 385, 283, and 190 bp for T. hydatigena, T. multiceps, T. pisiformis, and D. caninum, respectively. The lowest DNA concentration detected was 1 ng for T. hydatigena, T. multiceps and T. pisiformis, and 0.1 ng for D. caninum in a 25 µl reaction system. This assay offers high potential for the rapid detection of these four tapeworms in host feces simultaneously. CONCLUSIONS: This study provides an efficient tool for the simultaneous detection of T. hydatigena, T. multiceps, T. pisiformis, and D. caninum. The assay will be potentially useful in epidemiological studies, diagnosis, and treatment of these four cestodes infections during prevention and control program.
Assuntos
Cestoides , Infecções por Cestoides , Técnicas Microbiológicas/métodos , Reação em Cadeia da Polimerase Multiplex/métodos , Animais , Cestoides/genética , Cestoides/isolamento & purificação , Infecções por Cestoides/diagnóstico , Infecções por Cestoides/parasitologia , CãesRESUMO
GlnR, an OmpR-like orphan two-component system response regulator, is a master regulator of nitrogen metabolism in the genus Streptomyces In this work, evidence that GlnR is also directly involved in the regulation of antibiotic biosynthesis is provided. In the model strain Streptomyces coelicolor M145, an in-frame deletion of glnR resulted in markedly increased actinorhodin (ACT) production but reduced undecylprodigiosin (RED) biosynthesis when exposed to R2YE culture medium. Transcriptional analysis coupled with DNA binding studies revealed that GlnR represses ACT but activates RED production directly via the pathway-specific activator genes actII-ORF4 and redZ, respectively. The precise GlnR-binding sites upstream of these two target genes were defined. In addition, the direct involvement of GlnR in antibiotic biosynthesis was further identified in Streptomyces avermitilis, which produces the important anthelmintic agent avermectin. We found that S. avermitilis GlnR (GlnRsav) could stimulate avermectin but repress oligomycin production directly through the respective pathway-specific activator genes, aveR and olmRI/RII To the best of our knowledge, this report describes the first experimental evidence demonstrating that GlnR regulates antibiotic biosynthesis directly through pathway-specific regulators in Streptomyces Our results suggest that GlnR-mediated regulation of antibiotic biosynthesis is likely to be universal in streptomycetes. These findings also indicate that GlnR is not only a master nitrogen regulator but also an important controller of secondary metabolism, which may help to balance nitrogen metabolism and antibiotic biosynthesis in streptomycetes.
Assuntos
Proteínas de Bactérias/metabolismo , Ivermectina/análogos & derivados , Streptomyces/metabolismo , Transativadores/metabolismo , Proteínas de Bactérias/genética , Ivermectina/metabolismo , Streptomyces/genética , Transativadores/genéticaRESUMO
This study established a simple method of specifically detecting Salmonella species by amplifying fimW gene, which was involved in regulating Salmonella type I fimbriae expression. A pair of primers was designed to target and discriminate the 68 Salmonella strains of 23 Salmonella serovars available to us from 12 non-Salmonella strains of five different kinds of bacteria by polymerase chain reaction (PCR) amplification. Results showed that specific DNA fragment with an expected size of 477 bp was successfully amplified from all Salmonella serovars, while no target band was detected in non-Salmonella species. The sensitivity of this PCR-amplifying system reached to 1 pg DNA chromosome and 10(2) cfu of Salmonella enteritis strain CMCC(B) 50336. The above results demonstrated the method as a simple, sensitive, and specific way for Salmonella detection.
Assuntos
Proteínas de Bactérias/genética , Reação em Cadeia da Polimerase/métodos , Salmonella/genética , Primers do DNA/genética , Amplificação de Genes , Salmonella/isolamento & purificação , Sensibilidade e EspecificidadeRESUMO
To determine the genetic diversity of Haloxylon ammodendron collected from 14 sites in 5 provinces, 103 H. ammodendron samples of 12 wild populations and 2 cultivated which collected from 14 sites in 5 provinces were analyzed by amplified fragment length polymorphism (AFLP) DNA markers. PopGen32 and NTSYSpc2.1 was applied to evaluate genetic diversity of H. ammodendron populations. The average percentage of polymorphic loci (PPL) of total H. ammodendron populations was 94.13%, the average Nei's gene diversity index (H(e)) from 14 populations was 0.308 0, and the Shannon's genetic diversity index (I) was 0.467 6. The results indicated that the genetic diversity of H. ammodendron populations was high. Genetic differentiation index (G(st)) was 0.313 8, and the gene flow (N(m)) was 1.093 5 at the population level. The level of gene flow of H. ammodendron showed it possessed the feature of wind-pollinated outcrossing plants. AMOVA analysis indicated that genetic variation of H. ammodendron was much higher within groups (89.34%) than that among groups (10.66%), moreover genetic variation within groups mainly occurred among populations in different producing areas (84.80%). Cluster analysis (UPGMA) was applied to generate dendrogram based on Nei's genetic distances of 14 populations. Samples from Xinjiang and Qinghai were clustered respectively as a clade for their distant genetic relationship, while Samples from Gansu, Inner Mongolia and Ningxia were clustered together for their close genetic relationship. Genetic diversity of H. ammodendron populations is high in China, and genetic differentiation among regions is small, thus abundance within this specie is high at this stage. Therefore, wild nursery and artificial cultivating in different areas are effective measures for the conservation and sustainable utilization of H. ammodendron resources.
Assuntos
Amaranthaceae/genética , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Variação Genética , China , Evolução Molecular , FilogeniaRESUMO
Freeze pretreatment combined with alkaline-hydrothermal method of rice straw for enzymatic hydrolysis was studied. Crystallization stress in the rice stem pores caused by water freezing at -20- -40 °C was modeled to illustrate the destruction mechanism. The stress was calculated as 22.5-38.3 MPa that were higher than the tensile yield stress of untreated stems (3.0 MPa), indicating ice formation damaging pore structure. After freeze at -20 °C, rice straw was further hydrothermally treated at 190 °C with 0.4 M Na2CO3, achieving 72.0 % lignin removal and 97.2 % cellulose recovery. Glucose yield rose to 91.1 % by 4.3 times after 24 h hydrolysis at 10 FPU loading of Cellic®CTec2 cellulase. The specific surface area of rice straw was 2.6 m2/g increased by 1.2 times after freeze. Freeze combined with alkaline-hydrothermal treatment is a green and energy-efficient method for improving enzymatic hydrolysis.
Assuntos
Celulase , Congelamento , Oryza , Termodinâmica , Oryza/química , Hidrólise , Celulase/metabolismo , Álcalis/química , Álcalis/farmacologia , Água/química , Lignina/química , Celulose/química , Glucose/química , TemperaturaRESUMO
Classical swine fever (CSF)-like symptoms in pigs regarded as free from CSF has been reported previously. From sick pigs with CSF-like symptoms, and who had been inoculated with the hog cholera vaccine, samples were collected and subjected to RT-PCR using specific primers. Twelve bovine viral diarrhea virus 2 (BVDV-2) strains were screened and isolated. Homology comparison showed that the E2 genes of the twelve isolates were highly conserved. The genome of the one of the BVDV-2 isolates (named as SH-28) from the sick pigs, which showed a noncytopathic effect in MDBK cell cultures and strong reactivity with monoclonal antibody (MAb) Bz-53 raised against BVDV-2, was sequenced. The genome of SH-28 comprises 12,279 nucleotides and contains a large open reading frame beginning at nucleotide 386 and ending at nucleotide 12,073. Genomic comparison and phylogenetic analyzes showed that SH-28 fall into BVDV-2 subtype and was most similar to XJ-04 (nucleotide and amino acid homologies were 89.9-93.8 % and 91.1-96.9 %, respectively), but was genetically divergent from ZM-95 (pig BVDV-1).
Assuntos
Vírus da Diarreia Viral Bovina Tipo 2/classificação , Vírus da Diarreia Viral Bovina Tipo 2/isolamento & purificação , Diarreia/veterinária , Genoma Viral , Infecções por Pestivirus/veterinária , RNA Viral/genética , Doenças dos Suínos/virologia , Animais , Bovinos , Linhagem Celular , China , Análise por Conglomerados , Diarreia/virologia , Vírus da Diarreia Viral Bovina Tipo 2/genética , Genótipo , Dados de Sequência Molecular , Fases de Leitura Aberta , Infecções por Pestivirus/virologia , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , SuínosRESUMO
An accurate creeping ray-tracing algorithm is presented in this paper to determine the tracks of creeping waves (or creeping rays) on arbitrarily shaped free-form parametric surfaces [nonuniform rational B-splines (NURBS) surfaces]. The main challenge in calculating the surface diffracted fields on NURBS surfaces is due to the difficulty in determining the geodesic paths along which the creeping rays propagate. On one single parametric surface patch, the geodesic paths need to be computed by solving the geodesic equations numerically. Furthermore, realistic objects are generally modeled as the union of several connected NURBS patches. Due to the discontinuity of the parameter between the patches, it is more complicated to compute geodesic paths on several connected patches than on one single patch. Thus, a creeping ray-tracing algorithm is presented in this paper to compute the geodesic paths of creeping rays on the complex objects that are modeled as the combination of several NURBS surface patches. In the algorithm, the creeping ray tracing on each surface patch is performed by solving the geodesic equations with a Runge-Kutta method. When the creeping ray propagates from one patch to another, a transition method is developed to handle the transition of the creeping ray tracing across the border between the patches. This creeping ray-tracing algorithm can meet practical requirements because it can be applied to the objects with complex shapes. The algorithm can also extend the applicability of NURBS for electromagnetic and optical applications. The validity and usefulness of the algorithm can be verified from the numerical results.
RESUMO
BACKGROUND: Currently, little is known about the prognostic value of tumor growth rate (TGR) in spinal giant cell tumors of bone (GCTB). OBJECTIVE: To investigate the correlation of TGR with clinicopathological features, immune microenvironment, prognosis, and response to denosumab treatment of spinal GCTB. METHODS: A total of 128 patients with spinal GCTB treated at 5 centers from 2011 to 2021 were included. TGR was assessed by 2 independent neuroradiologists using at least 2 preoperative thin-section magnetic resonance imaging scans at a minimum interval of 2 months. Immunohistochemistry was used to assess tumor-infiltrating lymphocyte subtypes for CD3, CD4, CD8, CD20, PD-1, PD-L1, and Foxp3. Then, these parameters were analyzed for their associations with patient outcomes (progression-free survival and overall survival), clinicopathological features, and denosumab treatment responsiveness. RESULTS: High TGR predicted both poor progression-free survival and overall survival (both P < .001). In addition, TGR was associated with postoperative neurological dysfunction ( P < .001), Enneking staging ( P = .016), denosumab treatment responsiveness ( P = .035), and the number of CD3 + ( P < .001), PD-1 + ( P = .009), PD-L1 + ( P < .001), and FoxP3 + tumor-infiltrating lymphocyte ( P = .02). Importantly, TGR outperformed the traditional Enneking, Campanacci, and American Joint Committee on Cancer staging systems in predicting the clinical outcomes of spinal GCTB. CONCLUSION: These data support the use of TGR as a reliable predictive tool for clinically relevant outcomes and response to denosumab therapy of spinal GCTB, which may be helpful in guiding prognostic risk stratification and therapeutic optimization of patients.
Assuntos
Conservadores da Densidade Óssea , Neoplasias Ósseas , Tumor de Células Gigantes do Osso , Humanos , Denosumab/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Antígeno B7-H1 , Conservadores da Densidade Óssea/uso terapêutico , Receptor de Morte Celular Programada 1 , Tumor de Células Gigantes do Osso/diagnóstico por imagem , Tumor de Células Gigantes do Osso/tratamento farmacológico , Tumor de Células Gigantes do Osso/patologia , Fatores de Transcrição Forkhead/uso terapêutico , Microambiente TumoralRESUMO
Owing to the threats that Salmonella poses to public health and the abuse of antimicrobials, bacteriophage therapy against Salmonella is experiencing a resurgence. Although several phages have been reported as safe and efficient for controlling Salmonella, the genetic diversity and relatedness among Salmonella phages remain poorly understood. In this study, whole-genome sequences of 91 Salmonella bacteriophages were obtained from the National Center for Biological Information genome database. Phylogenetic analysis, mosaic structure comparisons, gene content analysis, and orthologue group clustering were performed. Phylogenetic analysis revealed four singletons and two major lineages (I-II), including five subdividing clades, of which Salmonella phages belonging to morphologically distinct families were clustered in the same clade. Chimeric structures (n = 31), holin genes (n = 18), lysin genes (n = 66), DNA packaging genes (n = 55), and DNA metabolism genes (n = 24) were present in these phages. Moreover, phages from different subdivided clusters harboured distinct genes associated with host cell lysis, DNA packaging, and DNA metabolism. Notably, phages belonging to morphologically distinct families shared common orthologue groups. Although several functional modules of phages SS1 and SE16 shared > 99% nucleotide sequence identity with phages SI2 and SI23, the major differences between these phages were the absence and replication of functional modules. The data obtained herein revealed the genetic diversity of Salmonella phages at genomic, structural, and gene content levels. The genetic diversity of Salmonella phages is likely owing to the acquisition, loss, and replication of functional modules.
Assuntos
Bacteriófagos , Fagos de Salmonella , Humanos , Fagos de Salmonella/genética , Filogenia , Genoma Viral , Bacteriófagos/genética , Salmonella/genética , DNA , Variação GenéticaRESUMO
The study of bacteriophages is experiencing a resurgence with the increasing development of antimicrobial resistance in Staphylococcus aureus. Nonetheless, the genetic features of highly efficient lytic S. aureus phage remain to be explored. In this study, two lytic S. aureus phages, SapYZU11 and SapYZU15, were isolated from sewage samples from Yangzhou, China. The phage morphology, one-step growth, host spectrum and lytic activity of these phages were examined, and their whole-genome sequences were analysed and compared with 280 published genomes of staphylococcal phages. The structural organisation and genetic contents of SapYZU11 and SapYZU15 were investigated. The Podoviridae phage SapYZU11 and Herelleviridae phage SapYZU15 effectively lysed all of the 53 S. aureus strains isolated from various sources. However, SapYZU15 exhibited a shorter latent period, larger burst size and stronger bactericidal ability with an anti-bacterial rate of approximately 99.9999% for 24 h. Phylogenetic analysis revealed that Herelleviridae phages formed the most ancestral clades and the S. aureus Podoviridae phages were clustered in the staphylococcal Siphoviridae phage clade. Moreover, phages in different morphology families contain distinct types of genes associated with host cell lysis, DNA packaging and lysogeny. Notably, SapYZU15 harboured 13 DNA metabolism-related genes, 5 lysin genes, 1 holin gene and 1 DNA packaging gene. The data suggest that S. aureus Podoviridae and Siphoviridae phages originated from staphylococcal Herelleviridae phages, and the module exchange of S. aureus phages occurred in the same morphology family. Moreover, the extraordinary lytic capacity of SapYZU15 was likely due to the presence of speciï¬c genes associated with DNA replication, DNA packaging and the lytic cycle.
Assuntos
Bacteriófagos , Siphoviridae , Infecções Estafilocócicas , Humanos , Staphylococcus aureus/genética , Esgotos , Filogenia , Infecções Estafilocócicas/microbiologia , Fagos de Staphylococcus/genéticaRESUMO
Bone regeneration heavily relies on bone marrow mesenchymal stem cells (BMSCs). However, recruiting endogenous BMSCs for in situ bone regeneration remains challenging. In this study, we developed a novel BMSC-aptamer (BMSC-apt) functionalized hydrogel (BMSC-aptgel) and evaluated its functions in recruiting BMSCs and promoting bone regeneration. The functional hydrogels were synthesized between maleimide-terminated 4-arm polyethylene glycols (PEG) and thiol-flanked PEG crosslinker, allowing rapid in situ gel formation. The aldehyde group-modified BMSC-apt was covalently bonded to a thiol-flanked PEG crosslinker to produce high-density aptamer coverage on the hydrogel surface. In vitro and in vivo studies demonstrated that the BMSC-aptgel significantly increased BMSC recruitment, migration, osteogenic differentiation, and biocompatibility. In vivo fluorescence tomography imaging demonstrated that functionalized hydrogels effectively recruited DiR-labeled BMSCs at the fracture site. Consequently, a mouse femur fracture model significantly enhanced new bone formation and mineralization. The aggregated BMSCs stimulated bone regeneration by balancing osteogenic and osteoclastic activities and reduced the local inflammatory response via paracrine effects. This study's findings suggest that the BMSC-aptgel can be a promising and effective strategy for promoting in situ bone regeneration.
RESUMO
Due to increasing morbidity worldwide, fractures are becoming an emerging public health concern. This study aimed to investigate the effect of metformin on the healing of osteoporotic as well as normal fractures. Type H vessels have recently been identified as a bone-specific vascular subtype that supports osteogenesis. Here, we show that metformin accelerated fracture healing in both osteoporotic and normal mice. Moreover, metformin promoted angiogenesis in vitro under hypoxia as well as type H vessel formation throughout fracture healing. Mechanistically, metformin increased the expression of HIF-1α, an important positive regulator of type H vessel formation, by inhibiting the expression of YAP1/TAZ in calluses and hypoxia-cultured human microvascular endothelial cells (HMECs). The results of HIF-1α or YAP1/TAZ interference in hypoxia-cultured HMECs using siRNA further suggested that the enhancement of HIF-1α and its target genes by metformin is primarily through YAP1/TAZ inhibition. Finally, overexpression of YAP1/TAZ partially counteracted the effect of metformin in promoting type H vessel-induced angiogenesis-osteogenesis coupling during fracture repair. In summary, our findings suggest that metformin has the potential to be a therapeutic agent for fractures by promoting type H vessel formation through YAP1/TAZ inhibition.
RESUMO
Escherichia coli F18 (ECF18) is a common porcine enteric pathogen. The pathogenicity of ECF18 bacteria depends on the existence of ECF18 receptor in the brush border membranes of piglet's small intestinal mucosa. Alpha (1) fucosyltransferase gene (FUT1) has been identified as the candidate gene controlling the adhesion to ECF18 receptor. The genetic variations in the position of M307 nucleotide in open reading frame of FUT1 have been proposed as a marker for selecting resistant pigs. The piglets were divided into three groups, AA, AG and GG, according to the genotypes present at M307 of FUT1. Small intestinal epithelium cells of piglets with AA, AG and GG genotypes were selected to test the adhesion capability of the wild type E.coli expressing F18ab fimbriae, the recombinant E. coli expressing F18ac fimbriae or the recombinant E. coli secreting and surface-displaying the FedF subunit of F18ab fimbriae, respectively. Here, we examined the distribution and expression of porcine FUT1 mRNA in different tissues in Sutai pigs using real-time PCR. The results showed that piglets with AA genotype show resistance, whereas piglets with GG or AG genotypes are sensitive to the pathogenic E. coli F18 in Sutai piglets. FUT1 was expressed in all the tissues that were examined, and the gene's expression was highest in the lungs. There was no significant difference in expression level among the three genotypes in the liver, lung, stomach and duodenum, where the gene expression was relatively high. The present analysis suggested that mutation at M307 in FUT1 gene determines susceptibility of small intestinal epithelium to E. coli F18 adhesion in Sutai piglet and the expression of FUT1 gene may be regulated by other factors or the mutation was likely to be in linkage disequilibrium with some cis-regulatory variants.
Assuntos
Infecções por Escherichia coli/veterinária , Fucosiltransferases/genética , Predisposição Genética para Doença/genética , Mutação/genética , Doenças dos Suínos/genética , Doenças dos Suínos/microbiologia , Animais , Aderência Bacteriana/genética , Primers do DNA/genética , Infecções por Escherichia coli/genética , Genótipo , Mucosa Intestinal/metabolismo , Desequilíbrio de Ligação , Reação em Cadeia da Polimerase em Tempo Real , Suínos , Galactosídeo 2-alfa-L-FucosiltransferaseRESUMO
Alpha (1,2) fucosyltransferase (FUT1) gene has been identified as a candidate gene for controlling the expression of the receptor for ETEC F18. The genetic variations in the position of M307 nucleotide in open reading frame of FUT1 have been proposed as a marker for selecting ETEC F18 resistant pigs. The polymorphisms of M307 in FUT1 of breeding base group for ETEC F18 resistance of Sutai pigs (Duroc × Meishan) was detected and their correlations to some immune indexes, growth and development ability, carcass traits and meat quality were also analyzed, which aimed to investigate feasibility of further breeding for diseases resistance based on M307 of FUT1 for Sutai pigs. After digested by Hin6 I, M307 of FUT1 gene could be divided into three kinds of genotypes, AA, AG, and GG. The frequencies were 0.235, 0.609, and 0.156, respectively. The results indicated that Sutai pigs with the AA genotype in M307 of FUT1 gene not only have relatively strong general disease resistance ability in piglets, but also have higher growth and development ability and stable carcass traits and meat quality. It is entirely feasible to raise the new strains of Sutai pigs resistant to Escherichia coli F18 based on genetic marker of the M307 position in FUT1gene.
Assuntos
Cruzamento , Resistência à Doença/genética , Fucosiltransferases/genética , Polimorfismo de Nucleotídeo Único/genética , Sus scrofa/genética , Sus scrofa/imunologia , Animais , Marcadores Genéticos , Carne/normas , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição/genética , Característica Quantitativa Herdável , Sus scrofa/crescimento & desenvolvimento , Galactosídeo 2-alfa-L-FucosiltransferaseRESUMO
Particle surface morphology is an important factor influencing sand structure and mechanical properties. In this study, the effect of sand particle sphericity on sand direct shear performance is investigated by using the discrete element method (DEM). Two ways are adapted to simulate different approaching methods from round particles to irregular sand. The macroresponse shows that irregular sand has a higher shear strength at lower normal stress than round particles. The shape of the particle has less influence on shear strength at higher normal stress. The irregular shape of sand leads to an increase in the shear band proportion. However, the shear band proportion is not related to the sphericity. Under all conditions, particles within the shear band have a larger average rotation angle than those outside the shear band. When the particle shape approaches round (regardless of the round particle proportion and particle shape), the average rotation angle of particles within and without shear bands increase, while the coordinate number and contact anisotropy decrease.