Biomedical subjects

Bo Han

Publications and source records attributed to Bo Han.

At least 19 recordsLinked to original sources

PubMed2026

Genomic and food-safety evaluation of Staphylococcus chromogenes in Chinese dairy milk.

Non-aureus staphylococci and mammaliicocci (NASM) cause mastitis and may contaminate milk and dairy products. Milk samples (n = 1916) from cows with subclinical or clinical mastitis (SCM and CM, respectively) were collected from 28 large-scale (> 500 lactating cows) Chinese dairy farms. Overall, 999 NASM isolates representing 19 species were identified by MALDI-TOF MS and cpn60 sequencing, with Staphylococcuschromogenes, Mammaliicoccus sciuri and Staphylococcus haemolyticus being most prevalent. Antimicrobial resistance (AMR) was determined with disc diffusion; non-susceptible to penicillin was most common (SCM, 30% and CM, 29%) whereas cefoxitin non-susceptible NASM accounted for 8-10% of isolates; among these, 12.5% carried mecA but none carried mecC. Galleria mellonella was used to assess virulence of 78 strains of S. chromogenes, a dominant species; subsequently, 32 strains, representing higher- and lower-virulence in the Galleria model, were selected for whole-genome sequencing and comparative genomics. S. chromogenes isolates from CM had higher virulence (p < 0.05) than those from SCM. The 32 genomes comprised 20 sequence types, indicating high genetic diversity. No robust genomic marker of Galleria virulence phenotype was identified in this selected WGS subset. Acquired resistance genes (n = 5) were detected, including a first report of fusC in S. chromogenes; the fusC-positive isolate had an elevated fusidic acid MIC (8 mg/L). Although S. chromogenes persisted in milk at 4 °C, pasteurization (64 °C for 30 min) reduced viable counts to below detection. This study provided new insights into the prevalence, AMR, genomic diversity, and dairy-chain relevance of milk-derived NASM, particularly S. chromogenes. However, the genomic findings were based on an intentionally selected WGS subset and should be interpreted as hypothesis-generating rather than population-representative.

Animals↗

PubMed2025

Serum N-glycomics for non-invasive detection of significant liver pathology across clinical phases of treatment-naïve chronic hepatitis B.

BACKGROUND: Early identification of significant liver pathology is crucial for timely antiviral intervention in individuals with chronic hepatitis B (CHB) infection. Current non-invasive methods show limited accuracy in detecting occult liver damage, particularly in those with normal ALT. This study evaluated serum N-glycan profiles for diagnosing significant liver pathology in treatment-naïve CHB patients across clinical phases. METHODS: This cross-sectional study analyzed 626 treatment-naïve CHB patients confirmed by liver biopsy, classified according to 2025 EASL guidelines. Serum N-glycan profiles were determined using DNA sequencer-assisted fluorophore-assisted carbohydrate electrophoresis. Significant liver pathology was defined as inflammation grade ≥ G2 and/or fibrosis stage ≥ S2 (per Scheuer scoring system). Multivariate logistic regression models were developed and compared with traditional non-invasive markers. RESULTS: Among 626 CHB patients, 66.0% had significant inflammation and 58.9% had significant fibrosis. Patients with significant pathology showed characteristic alterations, with elevated P1, P3, P6, P7, P11 peaks and decreased P0, P5, P8, P10 peaks (all p < 0.0001). Compared to respective infection phases, hepatitis phases showed P1 increases of 19.6% and 36% in HBeAg(+) and HBeAg(-) patients, with P11 increases of 82.4% and 73.4%, while P0 decreased by 20.3% and 27.6%, and P10 by 21.6% and 20.3%. Relative to mild pathology (G and S < 2), P1 increased by 27% in significant pathology (G and/or S ≥ 2), reaching 58.7%/48.7% in G4/S4 stages (vs. G0/S0). In ALT-normal HBeAg(+) infection phase, P1 increased by 80.2%/65.8% in G4/S4 stages (vs. G0/S0), with P2 also increasing by 54.1%/45.2%. Multivariate analysis identified P11 as strongest risk factor (OR = 3.84, 95%CI: 1.74-8.45, p = 0.0008), followed by P1 (OR = 2.04, 95%CI: 1.57-2.64, p < 0.0001) and P7 (OR = 1.75, 95%CI: 1.31-2.34, p = 0.0002), while P2 (OR = 0.07, 95%CI: 0.02-0.26, p < 0.0001) and P0 (OR = 0.30, 95%CI: 0.12-0.79, p = 0.0140) served as protective factors. The glycomics combined model (AUC = 0.876 (0.844-0.908)) achieved superior performance and outperformed the clinical model (AUC = 0.818 (0.779-0.857)), LSM (AUC = 0.817 (0.775-0.858)), APRI (AUC = 0.830 (0.792-0.867)), and FIB-4 (AUC = 0.672 (0.621-0.723)) (all p < 0.001), with 78.7% sensitivity and 83.2% specificity. The optimized model reached AUC = 0.917 (0.891-0.942) with accuracy 84.2%, with 78.7% sensitivity and 94.6% specificity. Both glycomics-based models maintained diagnostic capability in ALT-normal patients particularly in HBeAg(+) infection. CONCLUSIONS: Serum N-glycomics demonstrates promising potential for non-invasive identification of significant liver pathology in treatment-naïve CHB patients, providing an alternative approach for early treatment decisions, especially in ALT-normal patients with occult liver damage.

Humans↗

PubMed2007

Mapping the landscape of potentially primordial informational oligomers: oligodipeptides and oligodipeptoids tagged with triazines as recognition elements.

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Base Pairing↗

PubMed2006

Substring selection for biomedical document classification.

MOTIVATION: Attribute selection is a critical step in development of document classification systems. As a standard practice, words are stemmed and the most informative ones are used as attributes in classification. Owing to high complexity of biomedical terminology, general-purpose stemming algorithms are often conservative and could also remove informative stems. This can lead to accuracy reduction, especially when the number of labeled documents is small. To address this issue, we propose an algorithm that omits stemming and, instead, uses the most discriminative substrings as attributes. RESULTS: The approach was tested on five annotated sets of abstracts from iProLINK that report on the experimental evidence about five types of protein post-translational modifications. The experiments showed that Naive Bayes and support vector machine classifiers perform consistently better [with area under the ROC curve (AUC) accuracy in range 0.92-0.97] when using the proposed attribute selection than when using attributes obtained by the Porter stemmer algorithm (AUC in 0.86-0.93 range). The proposed approach is particularly useful when labeled datasets are small.

Abstracting and Indexing↗

PubMed2006

Expression of calcitonin receptor in rat mammary gland during lactation.

Calcitonin (CT) and calcitonin receptor (CTR) have been reported to play an important role in mammary tissue during pregnancy, lactation, and involution. In the present study, the expression and distribution of CTR mRNA in rat mammary tissue during pregnancy and lactation were investigated. As measured by real-time RT-PCR, CTR mRNA levels were increased only slightly during pregnancy, but increased markedly immediately postpartum and remained elevated through lactation, with the highest levels observed 14 days postpartum. In situ hybridization analysis showed that intense CTR mRNA signals were detected in the whole mammary gland. We performed immunohistochemistry to determine distribution of CTR in the mammary epithelium. CTR has been reported to act as an amylin receptor when heterodimerized with receptor activity modifying protein-1 (RAMP1) or RAMP3. mRNA expression of RAMP1 and RAMP3 in mammary tissue decreased during pregnancy and lactation, and amylin mRNA was undetectable, suggesting that up-regulated CTR in lactating mammary tissues binds CT rather than amylin. In primary cultures of mammary cells isolated from rat dams 14 days postpartum, CT produced a statistically significant decrease in thymidine incorporation. These results suggest that up-regulation of CTR during lactation may contribute to inhibition of mammary epithelial cell proliferation.

Animals↗

PubMed2006

Immune tolerance to cardiac myosin induced by anti-CD4 monoclonal antibody in autoimmune myocarditis rats.

Autoimmune myocarditis is a T-cell-mediated autoimmune disease. CD4-positive T cells are believed to be the most important for the initiation and mediation of the disease. This study was aimed at evaluating whether anti-CD4 monoclonal antibody could induce immune tolerance to porcine cardiac myosin and whether the immune tolerance could protect rats with autoimmune myocarditis from myocardial injury. Lewis rats were immunized with porcine cardiac myosin to induce experimental autoimmune myocarditis. Immune tolerance was induced by injections of anti-CD4 monoclonal antibody on days -2, -1, 0, and 1. Results showed that cardiac function of antibody-treated rats was significantly increased compared with untreated rats 18 days postimmunization examined by transthoracic echocardiography. Typical cardiac histopathological changes were observed obviously in untreated group but not in antibody-treated group. Lymphocytes obtained from antibody-treated group had no proliferative response to porcine cardiac myosin examined by lymphocyte proliferation assay. Serological examination showed that rats immunized with cardiac myosin could produce high levels of anti-cardiac myosin antibody. The administration of anti-CD4 monoclonal antibody significantly prevented the increase of them. Serum levels of Th1 cytokines were significantly down-regulated by antibody administration, while the production of Th2 cytokines were up-regulated or unaffected evaluated by enzyme-linked immunosorbent assay. It concluded that immune tolerance to porcine cardiac myosin could be induced by anti-CD4 monoclonal antibody in vivo, and cardiac dysfunction and myocardial injury could be prevented by induction of immune tolerance.

Animals↗

PubMed2006

Effects of CTLA4-Ig gene-modified dendritic cells on the corneal allografts.

In order to investigate the effects of mouse CTLA4Ig gene-modified dendritic cells (DCs) on the survival of the corneal allografts in rats, the plasmid PG\CTLA4Ig was transfected into DCs of F344 rats mediated by Lipofectamine 2000. The expression of CTLA4Ig was detected by immunofluorescent microscopy. The effects of donor DCs on the proliferation of T cells in Lewis rats (recipients) were tested by by CCK8. Corneal transplantation was performed from F344 rats to Lewis rats. The DCs modified with CTLA4Ig gene were injected into the Lewis rats on the day 0 and 3 after transplantation. The movement of the DCs after modification in vivo was observed by immunofluorescent microscopy, and the survival of corneal allografts was evaluated by Holland criterion. The results showed that the CTLA4Ig-modified DCs could restrain the proliferation of allogenetic T cells. The CTLA4Ig-modified DCs prolonged survival of corneal allografts. (P < 0.01). It was suggested that the injection of CTLA4Ig gene-modified DCs could obviously inhabit the allograft rejection and prolong the survival of corneal allografts.

Abatacept↗

PubMed2006

Myoepithelial carcinoma arising in an adenomyoepithelioma of the breast: case report with immunohistochemical and mutational analysis.

Adenomyoepithelioma (AME) of the breast is an uncommon tumor characterized by biphasic proliferation of both epithelial and myoepithelial cells. In rare instances, the epithelial, the myoepithelial or both components of an AME may become malignant. Described herein is the case of a 69-year-old woman who presented with myoepithelial carcinoma of the breast in an AME. Malignancy of myoepithelial component (MEC) was evidenced by the presence of cytological atypia, high mitotic rate, necrosis and local invasion. Immunohistochemical study demonstrated strong expression of P53 and phosphorylated extracellular signal-regulated kinase 1/2 in MEC. Laser capture microdissection technique and mutational analysis further revealed point mutation of the p53 gene (T-->G transversion at codon 270) in this population, but not in glandular epithelial cells or adjacent normal ductal epithelium. No mutations in exons 1 and 2 of the K-, H-, and N-ras genes were identified in any of the neoplastic component. To the authors' knowledge this is the first report of a mutation in the p53 gene in a malignant AME of the breast.

Aged↗

PubMed2006

Adrenomedullin: a tumor progression factor via angiogenic control.

Adrenomedullin (ADM) is a 52-amino acid peptide with structural homology to calcitonin gene-related peptide (CGRP) initially isolated from human pheochromocytoma. ADM is synthesized and is secreted from many mammalian tissues, including the adrenal medulla, endothelial and vascular smooth muscle cells, as well as the myocardium and central nervous system. ADM has been implicated as a mediator of several diseases such as cardiovascular and renal disorders, sepsis, inflammation, diabetes and cancer. ADM is also expressed in a variety of tumors, including breast, endometrial and prostate cancer. ADM has been shown to be a mitogenic factor capable of stimulating growth of several cancer cell types. In addition, ADM is a survival factor for certain cancer cells and an indirect suppressor of the immune response. ADM plays an important role in environments subjected to low oxygen tension, which is a typical feature of solid tumors. Under these conditions, ADM is up regulated and acts as a potent angiogenic factor promoting neovascularization. The major focus of this review will be on the role of ADM in cancer, with emphasis on its utility in diagnostic and prognostic terms, along with its relevance as a therapeutic target.

Adrenomedullin↗

PubMed2006

Calcitonin inhibits invasion of breast cancer cells: involvement of urokinase-type plasminogen activator (uPA) and uPA receptor.

There is a growing body of evidence indicating that calcitonin (CT) and calcitonin receptor (CTR) are involved in the regulation of cell growth, differentiation, and survival and in tissue development. However, the precise functional role of CT/CTR in breast cancer is still unknown. It is well established that the urokinase plasminogen activator (uPA) system plays an important role in breast cancer invasion and metastasis. The goal of this study was to investigate the effects of CT on regulation of the uPA system and invasive capacity of breast cancer cells. In the highly invasive MDA-MB-231 cell line, 10(-8) M CT decreased both uPA and uPAR mRNA and protein expression which was associated with inhibition of the extracellular signal-regulated kinase (ERK) 1/2 pathway. Furthermore, two weeks of CT administration to nude mice inhibited the expression of uPA mRNA in primary tumors by 25% (P<0.05), as compared to control, untreated animals. CT also inhibited the invasiveness of MDA-MB-231 cells by 37% (10(-8) M CT, P<0.05), as determined by a Matrigel invasion assay. To the best of our knowledge, this is the first report describing a direct effect of CT on breast cancer cell invasion. Our data might suggest a close link between CT signaling, the uPA-mediated pathway, and breast cancer invasion.

Animals↗

PubMed2005

Novel synthesis of nucleoside 5'-phosphoramidates through reaction of nucleoside triphosphates with amines mediated by trimethylsilyl chloride.

Reaction of nucleoside triphosphates (NTPs) with amines in pyridine mediated by trimethylsilyl chloride produced nucleoside 5'-phosphoramidates in moderate yields without any preprotection of nucleosides and amino acid methyl esters. The reaction pathway is very similar to the mechanism of the RNA capping reaction, DNA or RNA ligation reaction, and catalysis of hydrolases and nucleases involving the formation of covalent enzyme-NMP (nucleoside 5'-monophosphate) intermediates in biological systems, which could provide a valuable clue for the enzymatic reactions.

Amines↗

PubMed2005

Effects of moisture and temperature on the osteoinductivity of demineralized bone matrix.

Demineralized bone matrix (DBM) is a well established osteoinductive bone graft material. It has been mixed with a variety of carriers to adjust to different forms of handling for a variety of applications. The impact of the various carriers on osteoinductivity remains largely unknown. Using an in vitro cell culture assay and in vivo intramuscular implantations into nude rats, the effects of moisture from water-based carriers and the storage temperature on osteoinductivity were studied. In the dry state, DBM can preserve its osteoinductive activity when temperatures reached 65 degrees C, but in the presence of moisture, the activity decreases with incubation time. Nearly 90% of the DBM activity is lost when maintained for 5 weeks at 65 degrees C. This study further indicates that the structure and stability of the collagen network in DBM not only provide a scaffold for osteogenitor cell proliferation and differentiation, but also controls the release rate of osteoinductive growth factors.

Alkaline Phosphatase↗

PubMed2005

Chitosan/gelatin-based films crosslinked by proanthocyanidin.

Novel polymer networks consisting of crosslinked gelatin/chitosan were prepared by a solution casting technique. Methods for bulk crosslinking were developed to modify the gelatin/chitosan blends with the use of a nontoxic crosslinking reagent, proanthocyanidin (PA). FTIR spectral analyses of the preparations showed network formations of crosslinked gelatin, chitosan, and PA by amide and ester linkages. The crosslinked networks were stable in the aqueous state, and had improved mechanical properties and thermal stability when compared with nonlinked gelatin (G) and chitosan/gelatin (C/G) films. In vitro protease digestion and cell-culture studies showed that the PA-crosslinked C/G films are nontoxic and exhibited decreased biodegradation rate and a better ability to support cell adhesion and proliferation than noncrosslinked gelatin or chitosan alone. These results suggest that such a nontoxic crosslinked gelatin/chitosan scaffold can become a promising matrix for tissue-engineering applications.

Animals↗

PubMed2005

Regulatory effect of dexamethasone on aquaporin-1 expression in cultured bovine trabecular meshwork cells.

To evaluate the effect of dexamethasone on the expression of aquaporin-1 (AQP-1) in cultured bovine trabecular meshwork cells, bovine trabecular meshwork cells were cultured in vitro and reproduced to the third and the fourth generation, then treated with dexamethasone at the concentrations of 5, 25, 50, 250 microg/L respectively for 7 days. Immunohistochemical technique-supervision method was employed to measure, and image analysis system to analyze the expression of AQP-1 in normal cultured bovine trabecular meshwork cells and those treated with dexamethasone. In normal bovine trabecular meshwork cells, the grayscale of AQP-1 positive staining was 167.94 +/- 1.18, while it was 168.92 +/- 0.91, 176.72 +/- 1.80, 180.64 +/- 1.31, 185.64 +/- 1.58 in cells treated with 5, 25, 50, 250 microg/L concentrations of dexamethasone. When the concentration of dexamethasone was higher than 25 microg/L, the expression of AQP-1 was significantly inhibited (P < 0.05). The regulation of AQP-1 expression by dexamethasone in cultured bovine trabecular meshwork cells in vitro may be one of causes that retard the aqueous outflow in glucocorticoid- induced glaucoma.

Animals↗

PubMed2005

Transdermal delivery of amino acids and antioxidants enhance collagen synthesis: in vivo and in vitro studies.

One of the most visible changes associated with the aging process in humans relates to a progressive thinning of the skin. This results from a decline in both collagen and glycosaminoglycans, as well as from changes in their chemical structure and 3-dimentional organization. Transdermal administration of antioxidants, a -lipoic acid (LA) (0.5%) and proanthocyanidin PA) (0.3%) in a standard cosmetic vehicle base formulation supplemented with 2% benzyl alcohol as a penetration enhancer, a mixture of essential amino acids (0.2%), significantly enhanced collagen synthesis and deposition. The amino acid mixture was designed to mimic serum concentrations, with supplemental methionine added to provide additional sulfur. The histological appearance of the skin of mature female rats treated in this fashion reflected the increased deposition of collagen in the dermis as well as a thickened epidermal layer. The changes do not seem to be mediated by TGF- ss or PDGF, two growth factors known to stimulate collagen synthesis. At lower concentrations, a -lipoic acid did not affect cell proliferation but at higher doses, while it had an inhibitory effect on (3)H-thimidine uptake, it did enhance collagen production. Pronanthocyanidin did not affect cell proliferation but significantly increased collagen synthesis by cultured fibroblasts.

Administration, Cutaneous↗

PubMed2005

Provisional stenting for multivessel PCI.

BACKGROUND: Bare stents reduce acute complications and repeat revascularization following percutaneous coronary intervention (PCI), but are costly and may lead to in-stent restenosis. It remains unclear whether stents should be universally implanted or whether provisional stenting mainly to suboptimal balloon dilatation results is an acceptable approach for multivessel PCI. OBJECTIVE: To compare the long-term clinical restenosis and target lesion revascularization (TLR) of stented and non-stented coronary artery lesions in patients who had multivessel PCI. METHODS: We performed retrospective analysis of matched data from 129 consecutive patients who underwent multivessel PCI (at least optimal balloon angioplasty to one coronary artery segment and balloon angioplasty plus stenting to another coronary artery in the same patient, all lesions are de novo native coronary artery lesions with vessel diameter >/=2.5 mm). The study endpoint was restenosis and repeat revascularization at one-year follow-up. RESULTS: Baseline characteristics were similar in both groups. Low in-hospital MACE (3.1%). Acute myocardial infarction, emergency revascularization via either PCI or CABG was detected and angiographic success was achieved in 99.3% of lesions in both groups. The rate of clinically driven angiographic restenosis and TLR at one-year (follow-up 100%) was similar (17.1% versus 18.6%, P=0.871, and 13.9% versus 16.3%, P=0.728, for optimal balloon angioplasty versus provisional stenting. CONCLUSIONS: The main findings from this study are that long-term angiographic restenosis and TLR was comparable for optimal balloon angioplasty and provisional stenting, suggesting that provisional stenting is an acceptable approach for multivessel PCI.

Age Distribution↗

PubMed2005

Cutting balloons versus conventional long balloons for PCI of long coronary lesions.

BACKGROUND: PCI for long coronary lesions remains a challenge because of high incidence of early complications and late restenosis. Cutting balloon angioplasty may result in reduced procedural complications and late restenosis than angioplasty with conventional long balloons (LBA) due to minimized injury to the culprit arteries. OBJECTIVE: To compare the immediate and one-year outcomes of CBA and LBA for long coronary lesions. METHODS: 169 consecutive patients were retrospectively identified who underwent CBA or LBA for de novo lesions 20 mm in length and 2.5 mm in diameter. The primary endpoint was immediate procedural outcomes and angiographic restenosis at one year. RESULTS: CBA was performed in 54 patients (56 lesions) and LBA in 115 patients (151 lesions). Baseline characteristics were similar in both groups with a mean lesion length of 34.89+/-11.19 mm, and vessel diameter of 3.03+/-0.54 mm. CBA resulted in reduced incidence of side branch loss (23.2% versus 41.7%, P=0.022) which was associated with less peri-procedural infarction (OR: 11.39 (95% CI: 1.34-96.53), P=0.026). It also caused less dissection (23.2% versus 38.4%, P=0.048) leading to a trend of less provisional focal stenting (32.1% versus 41.1%, P=0.264). The rate of angiographic restenosis and clinically driven target lesion revascularization at one year (follow-up 91.1%) was similar (25% versus 21.2%, and 20.4% versus 20%, for CBA versus LBA, both P=NS). The mean event-free survival was also similar (10.15+/-0.45 months for CBA versus 9.50+/-0.39 months for LBA, P=NS). CONCLUSION: CBA demonstrated better immediate results and equivalent late results than LBA, and therefore, it may be considered a reasonable firstline approach for PCI of long coronary lesions.

Aged↗

PubMed2005

Combined small-cell carcinoma of the stomach: p53 and K-ras gene mutational analysis supports a monoclonal origin of three histological components.

Primary small-cell carcinoma (SmCC) is extremely rare in stomach. We reported an autopsy case of combined gastric SmCC with p53 and K-ras mutational analysis. Histologically, the tumour was composed of well-differentiated adenocarcinoma surrounding the central dominant SmCC component with scattered nests of squamous cell carcinoma. Immunohistochemically, all the neoplastic components revealed strong expression for p53 protein. Based on these findings, we hypothesized that these histologically different components originated from a same progenitor cell that possessed p53 mutation. Using Laser-capture microdissection technique and mutational analysis, we identified the same point mutations of p53 gene (A-->G transversion in codon 239) and K-ras gene (G-->A transversion in codon 13) in all the neoplastic components, but not in the adjacent normal gastric epithelium. Our results strongly support a hypothesis that the combined SmCC of stomach in this case was of monoclonal origin.

Adenocarcinoma↗