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Hongwei Liu

Publications and source records attributed to Hongwei Liu.

At least 19 recordsLinked to original sources
PubMed2026

Genetic evidence that advanced COVID-19 accelerates longitudinal brain atrophy: A Mendelian randomization study.

Coronavirus disease 2019 (COVID-19) was reported to persist long-term in the brain and leave several long-term neurologic sequelae. However, the causal relationship between COVID-19 and brain aging is still unknown. The genome-wide association study (GWAS) data on COVID-19 phenotypes (susceptibility, hospitalization, and severity), involving a total of 5,779,391 participants, were collected from the COVID-19 Host Genetics Initiative. In addition, GWAS data on longitudinal changes in 15 brain structures, assessed via magnetic resonance imaging across the lifespan, were sourced from the ENIGMA Consortium and involved 15,640 participants. Two-sample Mendelian randomization was conducted to infer the causal relationship between COVID-19 and longitudinal brain changes. Multi-trait GWAS meta-analysis, colocalization, and fine-mapping analyses were performed to identify shared genetic etiologies. H3K27me3 ChIP-seq was used to evaluate the regulatory effect of colocalized loci. Two-step Mendelian randomization was applied to explore potential mediating mechanisms across multi-omics layers, including proteomics, metabolomics, and immunomics. Our results showed that COVID-19 hospitalization (β = -262.405, P = .041) and severity (β = -177.676, P = .049) were genetically associated with atrophied volume of total brain during longitudinal change. This suggests that individuals with advanced COVID-19 may be more susceptible to accelerated global brain aging. Caudate was genetically affected by all COVID-19 phenotypes. Seven variants were shared between advanced COVID-19 and global brain aging. rs117169628 was colocalized between advanced COVID-19 and global brain aging, and exerted an inhibitory effect on CDH15 expression, further strengthening the causality. Six metabolites, 1 protein, and 1 immune trait were identified as potential mediators. Our study indicates that advanced COVID-19 might be genetically associated with accelerated brain aging. Brain health should be paid more attention in long COVID-19.

Humans↗
PubMed2025

Duration of Hospitalization is Associated with the Gut Microbiome in Patients Undergoing Hematopoietic Stem Cell Transplantation: Early Results from a Randomized Trial of Home Versus Hospital Transplantation.

Home-based hematopoietic stem cell transplantation (HCT) is an innovative care model with growing interest, but its impact on the gut microbiome remains unexplored in a randomized setting. We present interim results from the first randomized controlled trials (RCT) evaluating the effect of HCT location-home versus hospital-on gut microbial diversity and antimicrobial resistance (AMR) gene carriage. We hypothesize that patients randomized to undergo home HCT would have higher gut taxonomic diversity and lower AMR gene abundance compared to those undergoing standard hospital HCT. We analyzed stool samples from the first 28 patients enrolled in ongoing Phase II RCTs comparing home (n = 16) and hospital (n = 12) HCT at Duke University using shotgun metagenomic sequencing to compare taxa and AMR gene composition between groups. We also performed a secondary analysis comparing patients who received transplants at outpatient infusion clinics versus inpatient standard HCT to evaluate the influence of hospitalization duration. In the primary RCT analysis, taxonomic and AMR gene α- and β-diversity were comparable between home and hospital groups, reflecting similar durations of hospitalization despite group allocation. In contrast, secondary analyses demonstrated that patients transplanted in outpatient infusion clinics who experienced significantly reduced hospitalization had higher gut taxonomic α-diversity and differential β-diversity, although AMR gene diversity remained unchanged. In summary, randomization by transplant location did not impact the gut microbiota to the same extent as the duration of hospitalization, although secondary analyses were heavily confounded. Even when taxonomic differences were observed, AMR genes were similar between groups. This RCT represents a novel investigation into how care setting influences the gut microbiome during HCT. Our findings suggest that hospital duration, rather than randomization allocation alone, is the primary driver of microbial disruption. These results underscore the potential for reducing hospital duration to mitigate microbiome injury, thereby informing future interventions to reduce infection risk and improve patient outcomes.

Microbiome↗
PubMed2007

Characterization and online detection of aromatic alkaloids in the ascidian Lissoclinum cf. badium by liquid chromatography/UV detection mass spectrometry.

A detection method based on high-performance liquid chromatography coupled with ultraviolet diode-array detection and electrospray ionization ion trap tandem mass spectrometry (HPLC-UV-ESI-MS/MS) was developed to investigate the total alkaloids prepared from the ascidian Lissoclinum cf. badium. The aromatic alkaloids possessing polysulfide structures are the major bioactive constituents isolated from ascidians of the genera Lissoclinum, Eudistoma, and Polycitor. These compounds presented various important biological activities. The ESI-MS fragmentation behavior of this kind of alkaloids was studied, and the fragmentation was characterized by elimination of the NH(CH(3))(2) moiety. The use of reversed-phase HPLC/UV-ESI-MS allowed the online separation and detection of 25 aromatic alkaloids. This approach provided data that can be used for detection of biologically active aromatic alkaloids from marine organisms.

Alkaloids↗
PubMed2006

Adsorbed para-nitrophenol on HDTMAB organoclay--a TEM and infrared spectroscopic study.

para-Nitrophenol adsorbed on hexadecyltrimethylammonium bromide modified montmorillonite has been studied using a combination of X-ray diffraction TEM and infrared spectroscopy. Upon formation of the organoclay, the properties change from hydrophilic to hydrophobic. It is proposed that para-nitrophenol is adsorbed onto the water in the cation hydration sphere of the organoclay. As the cation is replaced by the surfactant molecules the para-nitrophenol replaces the surfactant molecules in the clay interlayer. Significant changes in the water vibrations occur in this process. Bands attributed to CH stretching and bending vibrations in general decrease as the concentration of the surfactant (CEC) increases up to 1.0 CEC. After this concentration the bands increase approaching a value the same as that of the surfactant. Strong changes occur in the HCH deformation modes of the methyl groups of the surfactant. These changes are attributed to the methyl groups locking into the siloxane surface of the montmorillonite. Such a concept is supported by changes in the SiO stretching bands of the montmorillonite siloxane surface. This study demonstrates that para-nitrophenol will penetrate into the untreated clay interlayer and replace the intercalated surfactant in surfactant modified clay, resulting in the change of the arrangement of the intercalated surfactant.

Journal Article↗
PubMed2006

The dual actions of angiogenesis and anti-apoptosis induced by an isolated fraction from Geum japonicum repair muscle ischemia.

The fundamental improvement of muscle ischemia requires the re-establishment of sufficient vessel network. Despite many kinds of drugs have been used for ischemia, effective angiogenic drug is very limited. Here, we reported the identification and isolation of a potent angiogenic fraction (angio-T) from Geum japonicum and assessment of its therapeutic effects on muscle ischemia by reconstituting the insufficient blood supply network and enhancing cell survival potential. It was demonstrated that angio-T not only significantly enhanced the proliferation of cultured HCAECs in vitro, but also significantly enhanced the survival potential of the myofibers at risk and neovascularization in ischemic muscles leading to reconstitution of these vessel networks, significant reduction of ischemic areas, and significant myofiber regeneration in ischemic area one week post-ischemia.

Animals↗
PubMed2006

A new function of a previously isolated compound that stimulates activation and differentiation of myogenic precursor cells leading to efficient myofiber regeneration and muscle repair.

Muscle repair following severe injury is slow and incomplete due to the limited regenerative capacity of muscles comprising the function. In this study, one pure compound structurally corresponding to triterpenoid, which can directly induce the activation, proliferation and maturation of quiescent satellite cells into myocytes in vitro, was isolated from Geum japonicum. The potential effect of this compound on myogenesis was further tested in repair of severe muscle injury. It was found that this compound could significantly stimulate the regenerative potential of the damaged muscle resulting in regeneration of myotubes and myotube bundles time-dependently replacing the damaged muscle tissues. This compound-mediated active regeneration of new myofibers repairing damaged muscles was probably due to its direct action on activation and proliferation of quiescent myogenic precursor cells and enhancement of their maturation into regenerating myotubes, as was demonstrated in our primary myogenic precursor cells culture experiments. The up-regulated expression of endogenous phospho-Akt1 in compound-treated myogenic precursor cells may also contribute to the process of myofiber regeneration and muscle repair probably via promoting myogenic cell survival capacity.

Animals↗
PubMed2006

[Effect of angiotensin II on transforming growth factor beta-induced fibroblast proliferation in human skin].

OBJECTIVE: To observe the effect of angiotensin II (Ang II) or/and transforming growth factor beta (TGF-beta) on human skin fibroblast proliferation, and to explore the possible signaling mechanism involved in their actions. METHODS: Cultured human skin fibroblasts were treated with different concentrations of Ang II (1 x 10(-10), 1 x 10(-9), 1 x 10(-8) and 1 x 10(-7) mol/L) , TGF-beta(0.1, 1.0 and 10.0 ng/ml), and 1 x 10(-10) mol/L Ang II + 0.1 ng/ml TGF-beta, respectively. The cell proliferation was determined by 3H-thymidine (3H-TdR) incorporation. The phosphorylation of extracellular signal-regulated kinases (ERK) was detected by Western blot. RESULTS: Ang II at 1 x 10(-9), 1 x 10(-8), 1 x 10(-7) mol/L or TGF-beta at 1.0, 10.0 ng/ml increased 3H-TdR incorporation into cultured skin fibroblasts dose-dependently. Ang II and TGF-beta at lower doses (1 x 10(-10) mol/L and 0.1 ng/ml, respectively) did not affect 3H-TdR incorporation into fibroblasts (P>0.05), whereas co-administration of both Ang II and TGF-beta at these doses significantly increased 3H-TdR incorporation into fibroblasts (P<0.05). Ang II at 1 x 10(-7) mol/L or TGF-beta at 10.0 ng/ml significantly increased ERK phosphorylation of fibroblasts after stimulation (P<0.01). Smaller doses of Ang II (1 x 10(-10) mol/L) or TGF-beta (0.1 ng/ml) did not influence ERK phosphorylation of fibroblasts, whereas co-administration of Ang II and TGF-beta at these doses significantly enhanced ERK phosphorylation (P<0.05). Total protein levels of ERK did not differ at different doses. CONCLUSION: These results indicate that Ang II and TGF-beta synergistically increase skin fibroblast proliferation, which is at least partly via enhancement of ERK activity.

Angiotensin II↗
PubMed2006

Recombinant human platelet-derived growth factor enhances repair of cutaneous full-thickness excision by increasing the phosphorylation of extracellular signal-regulated kinase in diabetic rat.

OBJECTIVE: To investigate the possible signaling mechanisms by which recombinant human platelet-derived growth factor (rhPDGF) accelerated healing of cutaneous wound in diabetic rats. METHODS: Four full-thickness skin wounds were incised in the back of 26 male Wistar diabetic rats. The wounded rats were divided into 3 groups (7 or 8 rats each group). One group without treatment was used as a control, and the other 2 groups were treated with rhPDGF at a dose of 7.0 microg/cm2 wound or vehicle (DMSO/0.9% NaCl, vol/vol 1:1) from 1 to 14 days. The wound healing was evaluated by the measurements of the wound volume and area. Immunofluorescent and immunohistochemical staining were used to examine the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) and the expression of proliferative cell nuclear antigen (PCNA), respectively. RESULTS: Granulation tissue appeared in the bed of wound after injury. The number of blood capillary buds and fibroblasts was greater in the rhPDGF-treated group than that in the other 2 groups. A lot of inflammatory cells infiltration and collagen deposition were observed in the wound. The wound-volume in the rhPDGF-treated group was smaller than that in control group (P < 0.05). The reepithelialization rate in rhPDGF-treated group was higher than that in the other 2 groups at 7 days after injury (P < 0.05). The expression of PCNA in reparative cells was higher in rhPDGF-treated group than in control group or vehicle-treated group at 3,7 days after injury (P < 0.05). The phosphorylation of ERK1/2 was stronger in rhPDGF-treated group than that in control group or vehicle group at 7 and 14 days after injury (P < 0.05). CONCLUSION: These results suggest that rhPDGF accelerates wound healing and improves healing quality by increasing the phosphorylation of ERK1/2.

Animals↗
PubMed2005

Controllable assembly of aligned ZnO nanowires/belts arrays.

We describe a simple method to assemble ZnO nanowires/belts into highly ordered arrays. ZnCu(2) alloy was used as the Zn source, which reacted with water vapor to generate ZnO nanocrystals. The reaction was performed in a mild way, which facilitated the easy control of the reaction conditions. By simply controlling the water bath temperature and carrier gas flux in our experiments, we obtained ZnO nanowires/belts aligned to form ordered arrays. The highly ordered nature of the ZnO arrays is suggested to be related both with the polarities of the H(2)O molecule and the ZnO (0001) surface. Photoluminescence (PL) microscopy revealed that the comblike structures had waveguide properties, where green light enhancement was observed at the tips of the branches. The light enhancement property reveals their promising applications as light source arrays.

Journal Article↗
PubMed2005

Single crystal SnO2 zigzag nanobelts.

Zigzag SnO2 nanobelts have been synthesized by evaporating tin grain in air. XRD, SEM, and TEM were employed to characterize the prepared samples. SEM images showed large amounts of zigzag nanobelts with periodic morphology. XRD result showed a pure tetragonal SnO2 phase. HRTEM and SAED revealed a single crystal structure with [010] zone axis on the whole zigzag zone. The zigzag structure is deduced to be formed by shifting the growth direction from [101] to [10] or vice versa. Growing nanobelts along different equivalent directions opens a new avenue for the preparation of novel nanostructured materials.

Journal Article↗
PubMed2005

Seven new meroditerpenoids, from the marine sponge Strongylophora strongylata, that inhibited the maturation of starfish oocytes.

Seven new meroditerpenoids, strongylophorines 13-19 (1-7), have been isolated together with the four known strongylophorines 2 (8), 3 (9), 4 (10), and 8 (11) by a screening method using oocytes of the starfish Asterina pectinifera from a marine sponge Strongylophora strongylata collected at Iriomote Island, Okinawa, Japan. The structures were assigned according to their spectral data. Ten strongylophorines inhibited the maturation of starfish oocytes in the range 1.1-37.6 microM (IC50), while strongylophorine 4 (10) was not active at 250 microM.

Animals↗
PubMed2005

Two new triterpenoid glycosides isolated from Aesculus assamica GRIFF.

Phytochemical study of the ethanol extract of the seeds of Aesculus assamica led to the isolation of two new triterpenoid saponins. The structure of the new compounds were elucidated on the basis of spectral data to be 28-O-acetyl-21-O-(4-O-angeloyl)-6-deoxy-beta-glucopyranosyl-3-O-[beta-glucopyranosyl(1-2)-O-[beta-glucopyranosyl(1-4)]-beta-glucuronopyranosyl]protoaescigenin (1), and 21-O-(4-O-angeloyl)-6-deoxy-beta-glucopyranosyl-3-O-[beta-glucopyranosyl(1-2)-O-[beta-glucopyranosyl(1-4)]-beta-glucuronopyranosyl]protoaescigenin (2). Their in vitro bioactivity against plant pathogenic fungus Pyricularia oryzae and cytotoxicity against K562 and HCT-15 cell lines were evaluated.

Aesculus↗
PubMed2004

Isolation and characterization of polybrominated diphenyl ethers as inhibitors of microtubule assembly from the marine sponge Phyllospongia dendyi collected at Palau.

Two new polybrominated diphenyl ethers (1 and 2) were isolated by bioassay-guided separations together with nine known compounds (3-11) from the marine sponge Phyllospongia dendyi collected from Palau. The structures were assigned on the basis of their spectral data. Compounds 3, 7, and 10 showed inhibitory activities to the assembly of microtubule proteins (IC(50): 29.6, 33.5, and 20.9 microM, respectively) and to the meiotic maturation of starfish oocytes (IC(50): 3.6, 4.2, and 4.2 microM, respectively), while 1, 2, 4-6, 8, 9, and 11 were not active at 100 microM. Two phenolic hydroxyls are required for their bioactivities.

Animals↗
PubMed2004

Wideband time-reversal imaging of an elastic target in an acoustic waveguide.

Time-reversal is addressed for imaging elastic targets situated in an acoustic waveguide. It is assumed that the target-sensor range is large relative to the channel depth. We investigate the theory of wideband time-reversal imaging of an extended elastic target, for which the target dimensions are large relative to the principal wavelengths. When performing time-reversal imaging one requires a forward model for propagation through the channel, and the quality of the resulting image may be used as a measure of the match between the modeled and actual (measured) channel parameters. It is demonstrated that the channel parameters associated with a given measurement may be determined via a genetic-algorithm (GA) search in parameter space, employing a cost function based on the time-reversal image quality. Example GA channel-parameter-inversion results and imagery are presented for measured at-sea data.

Journal Article↗
PubMed2003

Enhancement of DNA vaccine potency against herpes simplex virus 1 by co-administration of an interleukin-18 expression plasmid as a genetic adjuvant.

In this study, the immune-modulatory and vaccine effects of using an interleukin (IL)-18 expression plasmid as a genetic adjuvant to enhance DNA vaccine-induced immune responses were investigated in a mouse herpes simplex virus 1 (HSV-1) challenge model. BALB/c mice were immunized by three intramuscular inoculations of HSV-1 glycoprotein D (gD) DNA vaccine alone or in combination with a plasmid expressing mature IL-18 peptide. Both the serum IgG2a/IgG1 ratio and T helper 1-type (Th1) cytokines [IL-2 and interferon (IFN)-gamma] were increased significantly by the co-injection of the IL-18 plasmid compared with the injection of gD DNA alone. However, the production of IL-10 was inhibited by IL-18 plasmid co-injection. Furthermore, IL-18 plasmid co-injection efficiently enhanced antigen-specific lymphocyte proliferation and the delayed-type hypersensitivity response. When mice were challenged with HSV-1 at the cornea, co-injection of IL-18 plasmid with gD DNA vaccine showed significantly better protection, manifested as lower corneal lesion scores and faster recovery. These experiments indicate that co-injection of an IL-18 plasmid with gD DNA vaccine efficiently induces Th1-dominant immune responses and improves the protective effect against HSV-1 infection.

Adjuvants, Immunologic↗
PubMed2003

Two new pregnane glycosides from Dioscorea futschauensis R. KUNTH.

Two new pregnane glycosides (1, 2) together with two known saponins were isolated from the rhizomes of Dioscorea futschauensis R. KUNTH. The structures of 1 and 2 were established as 16alpha-methoxyl-3beta-[(O-alpha-L-rhamnopyranosyl-(1-->2)-O-[alpha-L-rhamnopyranosyl-(1-->4)]-beta-D-glucopyranosyl)oxy]pregn-5-en-20-one and 21-methoxyl-3beta-[(O-alpha-L-rhamnopyranosyl-(1-->2)-O-[alpha-L-rhamnopyranosyl-(1-->4)]-beta-D-glucopyranosyl)oxy]pregn-5,16-en-20-one, respectively, on the basis of two-dimension NMR (2D NMR) and other spectral analysis. Their in vitro bioactivity against plant pathogenic fungus Pyricularia oryzae and osteoblastic proliferation stimulatory activity in the UMR106 cell line were evaluated.

Ascomycota↗