Publications by authors named "Yiping W Han"

Article Synopsis
  • A gram-negative oral anaerobe, often found in colorectal cancer, produces a unique protein called FadA complex (FadAc) that aids in tumor development.
  • In two studies, increased levels of circulating anti-FadAc IgA antibodies were found in colorectal cancer patients compared to healthy controls and those with advanced adenomas, indicating a potential association with cancer presence and stage.
  • The results suggest that anti-FadAc IgA could serve as a useful biomarker for early detection of colorectal cancer, particularly for tumors located in the proximal area of the colon.
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Background And Aims: Although is the most important bacterial carcinogen in gastric cancer (GC), GC can emerge even after eradication. Studies suggest that various constituents of the gastric microbiome may influence GC development, but the role of individual pathogens is unclear.

Methods: Human gastric mucosal samples were analyzed by 16SrRNA sequencing to investigate microbiome composition and its association with clinical parameters, including GC risk.

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Background & Aims: Colorectal cancer is a leading cause of cancer death, and a major risk factor is chronic inflammation. Despite the link between colitis and cancer, the mechanism by which inflammation leads to colorectal cancer is not well understood.

Methods: To investigate whether different forms of inflammation pose the same risk of cancer, we compared several murine models of colitis (dextran sodium sulfate [DSS], 2,4,6-trinitrobenzene sulfonic acid, 4-ethoxylmethylene-2-phenyloxazol-5-one, Citrobacter rodentium, Fusobacterium nucleatum, and doxorubicin) with respect to their ability to lead to colonic tumorigenesis.

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Stillbirths account for half of all perinatal mortality, but the underlying cause of a significant portion of the cases remains unknown. We set out to test the potential role and extent of microbial infection in stillbirth through a case-control analysis of fetal cord blood collected from the multisite Stillbirth Collaborative Research Network. Cases ( = 60) were defined as stillbirths at >20 weeks of gestation, and controls ( = 176) were live births.

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Alzheimer's Disease (AD) is the most common form of dementia in older adults and has a devastating impact on the patient's quality of life, which creates a significant socio-economic burden for the affected individuals and their families. In recent years, studies have identified a relationship between periodontitis and AD. Periodontitis is an infectious/inflammatory disease that destroys the supporting periodontal structure leading to tooth loss.

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Article Synopsis
  • * Two main mechanisms are proposed: oral microorganisms might directly invade the fetal-placenta unit, or inflammatory substances from the mouth may impact this unit.
  • * While results from periodontal therapy are inconsistent, animal studies show that omega-3 fatty acid supplementation in mothers could help protect the fetus by reducing inflammation and bacterial growth in the placenta.
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Fusobacterium nucleatum (Fn) is a Gram-negative oral commensal, prevalent in various human diseases. It is unknown how this common commensal converts to a rampant pathogen. We report that Fn secretes an adhesin (FadA) with amyloid properties via a Fap2-like autotransporter to enhance its virulence.

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Background: Precesarean vaginal preparation significantly reduces postpartum infections. Although povidone-iodine is the most commonly used vaginal antiseptic, evidence suggests that chlorhexidine gluconate may be more effective.

Objective: We aimed to compare the bactericidal effect of chlorhexidine gluconate and povidone-iodine on vaginal bacterial colony counts in pregnancy.

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is a Gram-negative oral commensal anaerobe which has been increasingly implicated in various gastrointestinal (GI) disorders, including inflammatory bowel disease, appendicitis, GI cancers. The oral cavity harbors a diverse group of , and it is postulated that in the GI tract originate from the mouth. It is not known, however, if all oral translocate to the GI sites with equal efficiencies.

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Adverse pregnancy outcomes (APOs) have been defined as (a) pre-term birth, when there is a delivery before 37 completed weeks (<259 days); (b) pre-eclampsia, which is a multisystem disorder of pregnancy characterized by maternal hypertension and proteinuria after the 20th gestational week; (c) low and very low birthweight, depending on whether the weight of the baby is less of 2500 g or <1500 g and (d) the spontaneous death of the fetus with <20 weeks (miscarriage) or between 20 and 36 weeks (stillbirth). In 2012, during the Consensus Report from the Joint EFP/AAP workshop on periodontitis and systematic diseases the role of periodontal diseases on APOs was reviewed. Some years later, this evidence has grown, and an update on the literature regarding the mechanisms related to this potential association (APOs and periodontal diseases) needs to be presented.

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Background: Ischemia reperfusion injury (I/RI) is a common complication of cardiovascular diseases. Resolution of detrimental I/RI-generated prothrombotic and proinflammatory responses is essential to restore homeostasis. Platelets play a crucial part in the integration of thrombosis and inflammation.

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Postoperative infections remain a serious concern after cesarean delivery, the most common major surgical procedure in the United States. Multiple strategies have been proposed to combat this problem, including the addition of azithromycin to the standard preoperative antibiotic prophylaxis. However, as obstetricians, we have failed to uniformly adopt precesarean vaginal preparation despite convincing evidence from randomized controlled trials that this technique reduces postoperative rates of endometritis by more than 50%.

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, a Gram-negative oral anaerobe, is a significant contributor to colorectal cancer. Using an cancer progression model, we discover that stimulates the growth of colorectal cancer cells without affecting the pre-cancerous adenoma cells. Annexin A1, a previously unrecognized modulator of Wnt/β-catenin signaling, is a key component through which exerts its stimulatory effect.

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Fusobacterium nucleatum is an oral anaerobe prevalent in intrauterine infection associated with a wide spectrum of adverse pregnancy outcomes. We demonstrate here that F. nucleatum triggers placental inflammation through maternal, rather than paternal, TLR4-mediated signaling.

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Fusobacterium nucleatum is a Gram-negative anaerobic oral commensal associated with periodontal disease. F. nucleatum has been implicated in a wide spectrum of systemic diseases, including oral, gastro-intestinal, rheumatologic, and vascular pathologies.

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We explored the use of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) for identification of Fusobacterium nucleatum subspecies. MALDI-TOF MS spectra of five F. nucleatum subspecies (animalis, fusiforme, nucleatum, polymorphum, and vincentii) were analyzed and divided into four distinct clusters, including subsp.

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Fusobacterium nucleatum is an anaerobic oral commensal and a periodontal pathogen associated with a wide spectrum of human diseases. This article reviews its implication in adverse pregnancy outcomes (chorioamnionitis, preterm birth, stillbirth, neonatal sepsis, preeclampsia), GI disorders (colorectal cancer, inflammatory bowel disease, appendicitis), cardiovascular disease, rheumatoid arthritis, respiratory tract infections, Lemierre's syndrome and Alzheimer's disease. The virulence mechanisms involved in the diseases are discussed, with emphasis on its colonization, systemic dissemination, and induction of host inflammatory and tumorigenic responses.

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Fusobacterium nucleatum (Fn) has been associated with colorectal cancer (CRC), but causality and underlying mechanisms remain to be established. We demonstrate that Fn adheres to, invades, and induces oncogenic and inflammatory responses to stimulate growth of CRC cells through its unique FadA adhesin. FadA binds to E-cadherin, activates β-catenin signaling, and differentially regulates the inflammatory and oncogenic responses.

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Background: 16S rRNA-based genomic analyses have revolutionized our understanding of infectious diseases. Many cases which were recognized as "idiopathic" are now known to have an infectious etiology. Here, we present a proof-of-concept study to examine the microbial link between intra-amniotic infection (IAI) and early-onset neonatal sepsis (EONS).

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Objective: We examined the presence of bacterial DNA in synovial fluids of native or clinically aseptically failed prosthetic joints from patients having periodontal disease and arthritis to determine whether there is bacterial spread from the oral cavity to the joints.

Methods: A total of 36 subjects were enrolled in the study. Among these, 11 were diagnosed with rheumatoid arthritis (RA) and 25 were diagnosed with osteoarthritis (OA).

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FadA, a novel adhesin of periodontal pathogen Fusobacterium nucleatum is composed of two forms, pre-FadA and mature FadA (mFadA), constituting the functional FadA complex (FadAc). By electron microscopy, we observed that mFadA formed uniformly long and thin filaments, while FadAc formed heterogeneous filaments of varying lengths and widths, as well as "knots". Mutants in signal peptide or in the non-alpha-helical loop retaining heterogeneous structures had binding activity while those forming aggregates or long filaments lost activity.

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Fusobacterium nucleatum is a Gram-negative oral anaerobe, capable of systemic dissemination causing infections and abscesses, often in mixed-species, at different body sites. We have shown previously that F. nucleatum adheres to and invades host epithelial and endothelial cells via a novel FadA adhesin.

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Background: Intra-amniotic infection and/or inflammation (IAI) are important causes of preterm birth and early-onset neonatal sepsis (EONS). A prompt and accurate diagnosis of EONS is critical for improved neonatal outcomes. We sought to explore the cord blood proteome and identify biomarkers and functional protein networks characterizing EONS in preterm newborns.

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