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1.
World J Clin Cases ; 12(9): 1698-1703, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38576745

RESUMO

BACKGROUND: This study aimed to explore the possible etiology and treatment of severe fetal tachycardia in the absence of organic disease and provide a reference for clinical management of severe fetal tachycardia. CASE SUMMARY: A 29-year-old pregnant woman, with a gravidity 1 parity 0, presented with a fetal heart rate (FHR) of 243 beats per minute during a routine antenatal examination at 31 + 2 wk of gestation. Before termination of pregnancy at 38 wk of gestation, the FHR repeatedly showed serious abnormalities, lasting more than 30 min. However, the pregnant woman and the fetus had no clinical symptoms, and repeated examination revealed no organic lesions. The mother and the baby were regularly followed up. CONCLUSION: This was a case of severe fetal tachycardia with no organic lesions and management based on clinical experience.

2.
Sci Rep ; 14(1): 1812, 2024 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-38245625

RESUMO

Alagille Syndrome (ALGS) is a complex genetic disorder characterized by cholestasis, congenital cardiac anomalies, and butterfly vertebrae. The variable phenotypic expression of ALGS can lead to challenges in accurately diagnosing affected infants, potentially resulting in misdiagnoses or underdiagnoses. This study highlights novel JAG1 gene mutations in two cases of ALGS. The first case with a novel p.Pro325Leufs*87 variant was diagnosed at 2 months of age and exhibited a favorable prognosis and an unexpected manifestation of congenital hypothyroidism. Before the age of 2, the second patient was incorrectly diagnosed with liver structural abnormalities, necessitating extensive treatment. In addition, he exhibited delays in language acquisition that may have been a result of SNAP25 haploinsufficiency. The identification of ALGS remains challenging, highlighting the importance of early detection and genetic testing for effective patient management. The variant p.Pro325Leufs*87 is distinct from reported variants linked to congenital hypothyroidism in ALGS patients, thereby further confirming the clinical and genetic complexity of ALGS. This emphasizes the critical need for individualized and innovative approaches to diagnosis and medical interventions, uniquely intended to address the complexity of this syndrome.


Assuntos
Síndrome de Alagille , Hipotireoidismo Congênito , Humanos , Lactente , Masculino , Síndrome de Alagille/diagnóstico , Síndrome de Alagille/genética , China , Hipotireoidismo Congênito/genética , Testes Genéticos , Proteína Jagged-1/genética
4.
Mol Genet Genomic Med ; 12(1): e2298, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37817461

RESUMO

BACKGROUND: Hereditary tyrosinemia type III (HT III) is an extremely rare form of tyrosinemia, characterized by autosomal recessive inheritance and biallelic mutations in the HPD gene. The clinical presentation of HT III is variable and poorly understood, with symptoms ranging from developmental delay and intellectual impairment to seizures and intermittent ataxia. This study aimed to provide further insights into the clinical and genetic characteristics of HT III. METHODS: A 3-year-old girl, identified through newborn screening, was diagnosed with HT III using targeted next-generation sequencing. A comprehensive literature review was conducted, and the clinical, biochemical, and genetic findings of previously reported HT III patients were summarized and analyzed. RESULTS: The genetic analysis of the proband revealed compound heterozygous mutations in the HPD gene such as c.731C>T (p.A244V) and c.656C>T (p.T219M). Notably, the HPD p.A244V mutation had not been previously documented in public databases or the scientific literature. Bioinformatics analysis classified both variants as pathogenic variants. The patient exhibited persistent tyrosinemia, elevated levels of related metabolite derivatives, confirming the diagnosis of HT III. The review of previously published cases contributed to a better understanding of the clinical and genetic characteristics associated with HT III. CONCLUSION: Early diagnosis and prompt treatment in infancy are crucial for managing HT III effectively. Dietary therapy, particularly during childhood, plays a significant role in disease management. The findings from this study enhance our understanding of the genotype-phenotype associations in HT III and emphasize the importance of early intervention for improved patient outcomes.


Assuntos
Tirosinemias , Recém-Nascido , Feminino , Humanos , Pré-Escolar , Tirosinemias/genética , Mutação , Genótipo , Fenótipo , China
5.
Elife ; 122023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38085658

RESUMO

Antigen-induced B-cell receptor (BCR) signaling is critical for initiating and regulating B-cell activation. The actin cytoskeleton plays essential roles in BCR signaling. Upon encountering cell-surface antigens, actin-driven B-cell spreading amplifies signaling, while B-cell contraction following spreading leads to signal attenuation. However, the mechanism by which actin dynamics switch BCR signaling from amplification to attenuation is unknown. Here, we show that Arp2/3-mediated branched actin polymerization is required for mouse splenic B-cell contraction. Contracting B-cells generate centripetally moving actin foci from lamellipodial F-actin networks in the plasma membrane region contacting antigen-presenting surfaces. Actin polymerization driven by N-WASP, but not WASP, initiates these actin foci and facilitates non-muscle myosin II recruitment to the contact zone, creating actomyosin ring-like structures. B-cell contraction increases BCR molecular density in individual clusters, leading to decreased BCR phosphorylation. Increased BCR molecular density reduced levels of the stimulatory kinase Syk, the inhibitory phosphatase SHIP-1, and their phosphorylated forms in individual BCR clusters. These results suggest that N-WASP-activated Arp2/3, coordinating with myosin, generates centripetally moving foci and contractile actomyosin ring-like structures from lamellipodial networks, enabling contraction. B-cell contraction attenuates BCR signaling by pushing out both stimulatory kinases and inhibitory phosphatases from BCR clusters, providing novel insights into actin-facilitated signal attenuation.


Assuntos
Actinas , Actomiosina , Animais , Camundongos , Actinas/metabolismo , Citocinese , Polimerização , Receptores de Antígenos de Linfócitos B/metabolismo
6.
Front Genet ; 14: 1254556, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37693317

RESUMO

Hypoparathyroidism, deafness, and renal dysplasia (HDR) syndrome is an infrequent autosomal dominant genetic disorder caused by haploinsufficiency of the GATA binding protein 3 (GATA3) gene. In this report, we present a case study of a 6-year-old female patient manifesting seizures, tetany, hypoparathyroidism, and sensorineural hearing loss. A heterozygous variant, c.1050 + 2T>C, in the GATA3 gene was discovered by genetic testing. Moreover, a minigene splicing experiment revealed that the aforementioned variation causes incorrect splicing and premature cessation of protein synthesis. The clinical profile of the patient closely resembles the well-known phenomenology of HDR syndrome, supporting the association between the condition and the GATA3 variant. The challenges in early diagnosis highlight the importance of employing next-generation sequencing for timely detection of rare diseases. Additionally, this research contributes to a deeper understanding of the genotype-phenotype correlations in HDR syndrome, underscoring the critical need for improved diagnostic and therapeutic strategies.

7.
Front Neurol ; 14: 1170557, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37188304

RESUMO

Pantothenate kinase-associated neurodegeneration (PKAN) is a rare genetic neurodegenerative disorder with brain iron accumulation characterized as dysarthria, spasticity, cognitive impairment, parkinsonism, and retinopathy. PKAN is caused by biallelic mutations in the mitochondrial pantothenate kinase 2 (PANK2) gene. Herein, we report a 4-year-old patient with PKAN from a Han Chinese family, who presented with developmental regression, progressive inability to walk, and limb tremors. Neuroimaging demonstrated "eye-of-the-tiger" sign. Whole exome sequencing (WES) identified compound heterozygous mutations of c.1213T>G (p.Tyr405Asp) and c.1502T>A (p.Ile501Asn) in PANK2 gene. In addition, a review of all known PANK2 variants observed in reported PKAN patients was conducted, to improve understanding of the genotype-phenotype associations that occur in PKAN patients.

8.
bioRxiv ; 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36993351

RESUMO

Antigen-induced B-cell receptor (BCR) signaling is critical for initiating and regulating B-cell activation. The actin cytoskeleton plays essential roles in BCR signaling. Upon encountering cell-surface antigens, actin-driven B-cell spreading amplifies signaling, while B-cell contraction following spreading leads to signal attenuation. However, the mechanism by which actin dynamics switch BCR signaling from amplification to attenuation is unknown. Here, we show that Arp2/3-mediated branched actin polymerization is required for B-cell contraction. Contracting B-cells generate centripetally moving actin foci from lamellipodial F-actin networks in the B-cell plasma membrane region contacting antigen-presenting surfaces. Actin polymerization driven by N-WASP, but not WASP, initiates these actin foci and facilitates non-muscle myosin II recruitment to the contact zone, creating actomyosin ring-like structures. Furthermore, B-cell contraction increases BCR molecular density in individual clusters, leading to decreased BCR phosphorylation. Increased BCR molecular density reduced levels of the stimulatory kinase Syk, the inhibitory phosphatase SHIP-1, and their phosphorylated forms in individual BCR clusters. These results suggest that N-WASP-activated Arp2/3, coordinating with myosin, generates centripetally moving foci and contractile actomyosin ring-like structures from lamellipodial networks, enabling contraction. B-cell contraction attenuates BCR signaling by pushing out both stimulatory kinases and inhibitory phosphatases from BCR clusters, providing novel insights into actin-facilitated signal attenuation.

9.
Drug Deliv ; 30(1): 2173332, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36724178

RESUMO

Rheumatoid arthritis (RA), an autoimmune disease, is characterized by inflammatory cell infiltration that damages cartilage, disrupts bone, and impairs joint function. The therapeutic efficacy of RA treatments with the severely affected side remains unsatisfactory despite current treatment methods that primarily focus on anti-inflammatory activity, largely because of the complicatedly pathological mechanisms. A recently identified mechanism for RA development involves the interaction of RA autoantibodies with various proinflammatory cytokines to facilitate the formation of neutrophil extracellular traps (NETs), which increased inflammatory responses to express inflammatory cytokines and chemokines. Therefore, NETs architecture digestion may inhibit the positive-feedback inflammatory signal pathway and lessen joint damage in RA. In this work, deoxyribonuclease I (DNase) is connected to oxidized hyaluronic acid (OHA) via Schiff base reaction to extend the half-life of DNase. The modification does not influence the DNase activity for plasmid deoxyribonucleic acid hydrolysis and NETs' architecture disruption. Carboxymethyl chitosan is crosslinked with DNase-functionalised OHA (DHA) to form an injectable, degradable, and biocompatible hydrogel (DHY) to further strengthen the adhesive capability of DHA. Importantly, the collagen-induced arthritis model demonstrates that intra-articular injection of DHY can significantly reduce inflammatory cytokine expression and alleviate RA symptoms, which can be significantly improved by combining methotrexate. Here, a DNase-functionalised hydrogel has been developed for RA treatment by constantly degrading the novel drug target of NETs to decrease inflammatory response in RA.


Assuntos
Artrite Reumatoide , Armadilhas Extracelulares , Humanos , Armadilhas Extracelulares/metabolismo , Hidrogéis/metabolismo , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/patologia , Citocinas/metabolismo , Desoxirribonucleases/metabolismo , Desoxirribonucleases/uso terapêutico , Neutrófilos/metabolismo
10.
Biomater Sci ; 10(23): 6731-6739, 2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36281645

RESUMO

Rheumatoid arthritis (RA) is chronic inflammation characterized by abundant inflammatory cell infiltration and a major cause of joint function disruption. Despite current therapeutic strategies such as non-steroidal drugs or anti-cytokine biologics having shown promise for RA management, their side effects and clinical response rate remain unsatisfactory, attributed largely to the complicated pathomechanisms and multiplicity of the inflammatory cytokines. In this work, novel hybrid exosome-mimic nanovesicles equipped with broad-spectrum anti-inflammatory activity were developed for RA treatment. The hybrid nanovesicles (HNV) were prepared by fusing an M1 macrophage membrane into exosome-mimic nanovesicles extruded from M2 macrophages. The HNV inherit the anti-inflammatory properties of the M2 macrophages and cytokine receptors derived from the M1 membrane. Accordingly, the HNV possess comprehensive anti-inflammation activity via binding proinflammatory factors and releasing anti-inflammatory mediators. Furthermore, black phosphorus nanosheets (BP) were introduced into the HNV (HNV@BP) to eliminate inflammatory cells upon near-infrared (NIR) irradiation, which intrinsically decreases the inflammatory reaction. In a mouse model of collagen-induced arthritis, the HNV loaded with BP targeted and accumulated at the inflammed knee joints, exhibiting multimodal rheumatoid arthritis therapy combined with NIR irradiation through comprehensive inflammation suppression.


Assuntos
Artrite Experimental , Artrite Reumatoide , Exossomos , Camundongos , Animais , Exossomos/metabolismo , Fósforo , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/metabolismo , Macrófagos , Artrite Experimental/tratamento farmacológico , Artrite Experimental/metabolismo , Citocinas/metabolismo , Inflamação/metabolismo
11.
J Med Biochem ; 41(3): 341-346, 2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-36042897

RESUMO

Background: Non-invasive prenatal screening (NIPS) is a highly sensitive and specific screening test to detect fetal chromosomal abnormalities. The primary objective of this study was to evaluate the NIPS as an effective method for prenatal detection of aneuploidies in both high-risk and low-risk pregnancies. Methods: In current study, we performed NIPS in 32,394 pregnancies, out of which results were available in 32,361 (99.9%) of them. Illumina sequencing was performed for NIPS screening. Hypothesis Z test was used to classify fetal autosomal aneuploidy of T21, T18, and T13. Karyotyping was performed to determine the true negative and true positive NIPS results. Results: Among the 32,361 confirmed samples, 164 cases had positive results and 32197 cases had negative results. Of these positive cases, 116 cases were trisomy 21, 34 cases were trisomy 18 and 14 cases were trisomy 13. No false negative results were found in this cohort. The overall sensitivity and specificity were 100% and 99.91%, respectively. There was no significant difference in test performance between the 7,316 high-risk and 25,045 low-risk pregnancies, (sensitivity, 100% vs 100% (P>0.05); specificity, 99.96% vs 99.95% (P > 0.05)). Factors contributing to false-positive results included fetal copy number variants (CNVs), fetal mosaicism and typically producing Z scores between 3 and 4. Moreover, we analyzed NIPS wholegenome sequencing to investigate the Single Nucleotide Polymorphisms (SNPs) associations with drug response or risk of disease. As compare to the 1000g East Asian genome data, the results revealed a significant difference in 7,285,418 SNPs variants of Shanxi pregnant women including 19,293 clinvar recorded variants and 7,266,125 non-clinvar recorded. Conclusions: Our findings showed that NIPS was an effective assay that may be applied as routine screening for fetal trisomies in the prenatal setting. In addition, this study also provides an accurate assessment of significant differences in 7,285,418 SNPs variants in Shanxi pregnant women that were previously unavailable to clinicians in Shanxi population.

13.
Front Genet ; 13: 887176, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35719402

RESUMO

Objective: To evaluate positive rate and accuracy of non-invasive prenatal testing (NIPT) combining Z-score and maternal copy number variation (CNV) analysis. To assess the relationship between Z-score and positive predictive value (PPV). Methods: This prospective study included 61525 pregnancies to determine the correlation between Z-scores and PPV in NIPT, and 3184 pregnancies to perform maternal CNVs analysis. Positive results of NIPT were verified by prenatal diagnosis and/or following-up after birth. Z-score grouping, logistic regression analysis, receiver operating characteristic (ROC) curves, and S-curve trends were applied to correlation analysis of Z-scores and PPV. The maternal CNVs were classified according to the technical standard for the interpretation of ACMG. Through genetic counseling, fetal and maternal phenotypes and family histories were collected. Results: Of the 3184 pregnant women, 22 pregnancies were positive for outlier Z-scores, suggesting fetal aneuploidy. 12 out of 22 pregnancies were true positive (PPV = 54.5%). 17 pregnancies were found maternal pathogenic or likely pathogenic CNVs (> 0.5 Mb) through maternal CNV analysis. Prenatal diagnosis revealed that 7 out of 11 fetuses carried the same CNVs as the mother. Considering the abnormal biochemical indicators during pregnancy and CNV-related clinical phenotypes after birth, two male fetuses without prenatal diagnosis were suspected to carry the maternally-derived CNVs. Further, we identified three CNV-related family histories with variable phenotypes. Statistical analysis of the 61525 pregnancies revealed that Z-scores of chromosomes 21 and 18 were significantly associated with PPV at 3 ≤ Z ≤ 40. Notably, three pregnancies with Z > 40 were both maternal full aneuploidy. At Z < -3, fetuses carried microdeletions instead of monosomies. Sex chromosome trisomy was significantly higher PPV than monosomy. Conclusion: The positive rate of the NIPT screening model combining Z-score and maternal CNV analysis increased from 6.91‰ (22/3184) to 12.25‰ (39/3184) and true positives increased from 12 to 21 pregnancies. We found that this method could improve the positive rate and accuracy of NIPT for aneuploidies and CNVs without increasing testing costs. It provides an early warning for the inheritance of pathogenic CNVs to the next generation.

14.
Front Immunol ; 13: 842605, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35493485

RESUMO

Antigen (Ag)-triggered B-cell receptor (BCR) signaling initiates antibody responses. However, prolonged or uncontrolled BCR signaling is associated with the development of self-reactive B-cells and autoimmune diseases. We previously showed that actin-mediated B-cell contraction on Ag-presenting surfaces negatively regulates BCR signaling. Non-muscle myosin II (NMII), an actin motor, is involved in B-cell development and antibody responses by mediating B-cell migration, cytokinesis, and Ag extraction from Ag-presenting cells. However, whether and how NMII regulates humoral responses through BCR signaling remains elusive. Utilizing a B-cell-specific, partial NMIIA knockout (cIIAKO) mouse model and NMII inhibitors, this study examined the role of NMII in BCR signaling. Upon BCR binding to antibody-coated planar lipid bilayers (PLB), NMIIA was recruited to the B-cell contact membrane and formed a ring-like structure during B-cell contraction. NMII recruitment depended on phosphatidylinositol 5-phosphatase (SHIP1), an inhibitory signaling molecule. NMII inhibition by cIIAKO did not affect B-cell spreading on PLB but delayed B-cell contraction and altered BCR clustering. Surface BCR "cap" formation induced by soluble stimulation was enhanced in cIIAKO B-cells. Notably, NMII inhibition by cIIAKO and inhibitors up-regulated BCR signaling in response to both surface-associated and soluble stimulation, increasing phosphorylated tyrosine, CD79a, BLNK, and Erk and decreasing phosphorylated SHIP1. While cIIAKO did not affect B-cell development, the number of germinal center B-cells was significantly increased in unimmunized cIIAKO mice, compared to control mice. While cIIAKO mice mounted similar antibody responses when compared to control mice upon immunization, the percentages of high-affinity antibodies, Ag-specific germinal center B-cells and isotype switched B-cells were significantly lower in cIIAKO mice than in control mice. Furthermore, autoantibody levels were elevated in cIIAKO mice, compared to control mice. Collectively, our results reveal that NMII exerts a B-cell-intrinsic inhibition on BCR signaling by regulating B-cell membrane contraction and surface BCR clustering, which curtails the activation of non-specific and self-reactive B-cells.


Assuntos
Actinas , Receptores de Antígenos de Linfócitos B , Actinas/metabolismo , Animais , Antígenos/metabolismo , Linfócitos B , Ativação Linfocitária , Camundongos , Miosina Tipo II/metabolismo , Receptores de Antígenos de Linfócitos B/metabolismo
15.
Zhongguo Gu Shang ; 35(3): 276-80, 2022 Mar 25.
Artigo em Chinês | MEDLINE | ID: mdl-35322620

RESUMO

OBJECTIVE: Osteosarcoma(OS) and Ewing's sarcoma (EWS) are the two most common primary malignant bone tumors in children. The aim of the study was to identify key genes in OS and EWS and investigate their potential pathways. METHODS: Expression profiling (GSE16088 and GSE45544) were obtained from GEO DataSets. Differentially expressed genes were identified using GEO2R and key genes involved in the occurrence of both OS and EWS were selected using venn diagram. Gene ontology and pathway enrichment analyses were performed for the ensembl. Protein-protein interaction (PPI) networks were established by STRING. Further, UCSC was used to predict the transcription factors of the cell division cycke 5-like(CDC5L) gene, and GEPIA was used to analyze the correlation between the transcription factors and the CDC5L gene. RESULTS: The results showed that CDC5L gene was the key gene involved in the pathogenesis of OS and EWS. The gene is mainly involved in mitosis, and is related to RNA metabolism, processing of capped intron-containing pre-mRNA, mRNA and pre-mRNA splicing. CONCLUSION: CDC5L, as a key gene, plays a role in development of OS and EWS, which may be reliable targets for diagnosis and treatment of these primary malignant tumors.


Assuntos
Neoplasias Ósseas , Proteínas de Ciclo Celular , Osteossarcoma , Proteínas de Ligação a RNA , Sarcoma de Ewing , Neoplasias Ósseas/genética , Neoplasias Ósseas/patologia , Proteínas de Ciclo Celular/genética , Criança , Biologia Computacional , Perfilação da Expressão Gênica , Humanos , Osteossarcoma/genética , Proteínas de Ligação a RNA/genética , Sarcoma de Ewing/genética
16.
Appl Microbiol Biotechnol ; 106(7): 2529-2540, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35318522

RESUMO

Cytophaga hutchinsonii is an important Gram-negative bacterium belonging to the Bacteroides phylum that can efficiently degrade cellulose. But the promoter that mediates the initiation of gene transcription has been unknown for a long time. In this study, we determined the transcription start site (TSS) of C. hutchinsonii by 5' rapid amplification of cDNA ends (5'RACE). The promoter structure was first identified as TAAT and TATTG which are located -5 and -31 bp upstream of TSS, respectively. The function of -5 and -31 regions and the spacer length of the promoter Pchu_1284 were explored by site directed ligase-independent mutagenesis (SLIM). The results showed that the promoter activities were sharply decreased when the TTG motif was mutated into guanine (G) or cytosine (C). Interestingly, we found that the strong promoter was accompanied with many TTTG motifs which could enhance the promoter activities within certain copies. These characteristics were different from other promoters of Bacteriodes species. Furthermore, we carried out genome scanning analysis for C. hutchinsonii and another Bacteroides species by Perl6.0. The results indicated that the promoter structure of C. hutchinsonii possessed more unique features than other species. Also, the screened inducible promoter Pchu_2268 was used to overexpress protein CHU_2196 with a molecular weight of 120 kDa in C. hutchinsonii. The present study enriched the promoter structure of Bacteroidetes species and also provided a novel method for the highly expressed large protein (cellulase) in vivo, which was helpful to elucidate the unique cellulose degradation mechanism of C. hutchinsonii.Key points• The conserved structure of strong promoter of C. hutchinsonii was elucidated.• Two novel regulation motifs of TTTG and AATTATG in the promoter were discovered.• A new method for induced expression of cellulase in vivo was established.• Helpful for explained the unique cellulose degradation mechanism of C. hutchinsonii.


Assuntos
Celulase , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Celulase/metabolismo , Celulose/metabolismo , Cytophaga/genética , Cytophaga/metabolismo
17.
Pathogens ; 11(2)2022 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-35215160

RESUMO

Gonorrhea is the second most common sexually transmitted infection, which is primarily localized but can be disseminated systemically. The mechanisms by which a localized infection becomes a disseminated infection are unknown. We used five pairs of Neisseria gonorrhoeae isolates from the cervix/urethra (localized) and the blood (disseminated) of patients with disseminated gonococcal infection to examine the mechanisms that confine gonococci to the genital tract or enable them to disseminate to the blood. Multilocus sequence analysis found that the local and disseminated isolates from the same patients were isogenic. When culturing in vitro, disseminated isolates aggregated significantly less and transmigrated across a polarized epithelial monolayer more efficiently than localized isolates. While localized cervical isolates transmigrated across epithelial monolayers inefficiently, those transmigrated bacteria self-aggregated less and transmigrated more than cervical isolates but comparably to disseminating isolates. The local cervical isolates recruited the host receptors of gonococcal Opa proteins carcinoembryonic antigen-related cell adhesion molecules (CEACAMs) on epithelial cells. However, the transmigrated cervical isolate and the disseminated blood isolates recruit CEACAMs significantly less often. Our results collectively suggest that switching off the expression of CEACAM-binding Opa(s), which reduces self-aggregation, promotes gonococcal dissemination.

18.
Front Cell Dev Biol ; 10: 819050, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35223845

RESUMO

[This corrects the article DOI: 10.3389/fcell.2021.646077.].

19.
J Microbiol ; 60(4): 364-374, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34994957

RESUMO

Cytophaga hutchinsonii can efficiently degrade crystalline cellulose, in which the cell surface cellulases secreted by the type IX secretion system (T9SS) play important roles, but the degradation mechanism remains unclear, and the anchor mechanism of cellulases on the outer membrane in C. hutchinsonii has not been studied. Here, chu_2177 was identified by transposon mutagenesis and was proved to be indispensable for cellulose utilization in C. hutchinsonii. Disruption of chu_2177 resulted in O-antigen deficiency and chu_177 could confer O-antigen ligase activity upon an Escherichia coli waal mutant, indicating that chu_2177 encoded the O-ntigen ligase. Moreover, deletion of chu_2177 caused defects in cellulose utilization, cell motility, biofilm formation, and stress resistance. Further study showed that the endoglucanase activity was markedly decreased in the outer membrane but was increased in the culture fluid without chu_2177. Western blot proved that endoglucanase CHU_1336 was not located on the outer membrane but was released in the culture fluid of the Δ2177 mutant. Further proteomics analysis showed that many cargo proteins of T9SS were missing in the outer membrane of the Δ2177 mutant. Our study revealed that the deletion of chu_2177 affected the localization of many T9SS cargo proteins including cellulases on the outer membrane of C. hutchinsonii.


Assuntos
Ligases , Antígenos O , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Celulose/metabolismo , Cytophaga/genética , Cytophaga/metabolismo , Ligases/metabolismo , Antígenos O/metabolismo
20.
Environ Toxicol ; 37(4): 910-924, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34995009

RESUMO

The alpha-ketoglutarate-dependent (ALKB) homolog 5 (ALKBH5), an m6 A demethylase, has been reported to be involved in the pathogenesis of preeclampsia (PE), but the exact mechanism requires further investigation. RT-qPCR or Western blotting were used to determine ALKBH5 and peroxisome proliferator-activated receptor gamma (PPARG) expression in placentas from PE patients and normal volunteers, as well as in HTR-8/SVneo cells treated with hypoxia/reoxygenation (H/R). Our results showed that the expression of ALKBH5 was significantly upregulated and PPARG was downregulated in preeclamptic placentas and H/R-treated cells. ALKBH5 interference reduced m6 A levels of PPARG mRNA, and increased PPARG mRNA stability and promoted PPARG translation level. In addition, ALKBH5 silencing increased the cell proliferation, migration, and vimentin protein level, and inhibited cell apoptosis, oxidative stress, and protein levels of endoglin (ENG) and E-cadherin in H/R-treated cells, whereas PPARG interference reversed these effects. Furthermore, PPARG repressed the H3K9me2 levels at activated leukocyte cell adhesion molecule (ALCAM) promoter region by increasing the expression and activity of lysine demethylase 3B (KDM3B). ALCAM inhibition reversed the effects of PPARG overexpression on H/R-treated cell functions. PKF115-584 suppressed the effects of ALKBH5 interference on the behaviors of H/R-treated cells. Finally, inhibition of ALKBH5 alleviates PE-like features in pregnant mice. Inhibition of ALKBH5 promotes KDM3B-mediated ALCAM demethylation by facilitating PPARG mRNA m6 A modification, and further activates the Wnt/ß-catenin pathway, and in turn alleviates PE progression.


Assuntos
Homólogo AlkB 5 da RNA Desmetilase , Trofoblastos , Homólogo AlkB 5 da RNA Desmetilase/genética , Homólogo AlkB 5 da RNA Desmetilase/metabolismo , Animais , Apoptose/genética , Feminino , Humanos , Hipóxia/metabolismo , Histona Desmetilases com o Domínio Jumonji/genética , Histona Desmetilases com o Domínio Jumonji/metabolismo , Histona Desmetilases com o Domínio Jumonji/farmacologia , Camundongos , Estresse Oxidativo/genética , PPAR gama/genética , PPAR gama/metabolismo , Placenta/metabolismo , Gravidez , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Trofoblastos/metabolismo
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