Linna Guo

Dr. Linna Guo

University Hospital Hamburg-Eppendorf
orcid

Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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Verified
Journal Article
Open access
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LGLinna Guo
Linna Guo
Ralf SmeetsRalf Smeets
Ralf Smeets
LKLan Kluwe
Lan Kluwe
PHPhilip Hartjen
Philip Hartjen
Mike BarbeckMike Barbeck
Mike Barbeck
Anders HenningsenAnders Henningsen
Anders Henningsen
A number of modifications have been developed in order to enhance surface cytocompatibility for prosthetic support of dental implants. Among them, ultraviolet (UV) light and non-thermal plasma (NTP) treatment are promising methods. The objective of this study was to compare the effects of UV light and NTP on machined titanium, zirconia and modified polyetheretherketone (PEEK, BioHPP) surfaces in vitro. Machined samples of titanium, zirconia and BioHPP were treated by UV light and NTP of argon or oxygen for 12 min each. Non-treated disks were set as controls. A mouse fibroblast and a human gingival fibroblast cell line were used for in vitro experiments. After 2, 24 and 48 h of incubation, the attachment, viability and cytotoxicity of cells on surfaces were assessed. Results: Titanium, zirconia and BioHPP surfaces treated by UV light and oxygen plasma were more favorable to the early attachment of soft-tissue cells than non-treated surfaces, and the number of cells on those treated surfaces was significantly increased after 2, 24 and 48 h of incubation (p < 0.05). However, the effects of argon plasma treatment on the cytocompatibility of soft tissue cells varied with the type of cells and the treated material. UV light and oxygen plasma treatments may improve the attachment of fibroblast cells on machined titanium, zirconia and PEEK surfaces, that are materials for prosthetic support of dental implants.

21 June 2022 in Cell Reports
Verified
Journal Article
Open access
JTJiao-Jiao Tang
Jiao-Jiao Tang
YPYu-Fei Pan
Yu-Fei Pan
CCCan Chen
Can Chen
XCXiuliang Cui
Xiuliang Cui
ZYZi-Jun Yan
Zi-Jun Yan
HWHongyang Wang
Hongyang Wang
The liver is one of the most-favored distant metastatic sites for solid tumors, and interactions between cancer cells and components of the hepatic microenvironment are essential for liver metastasis (LM). Although sex is one of the determinants for primary liver cancer, sexual dimorphism in LM (SDLM) and the underlying mechanisms remain unclear. We herein demonstrate a significant male-biased SDLM, which is attributed to host androgen/androgen receptor (Ar) signaling that promotes hepatic seeding of tumor cells and subsequent outgrowth in a neutrophil-dependent manner. Mechanistically, androgen/Ar signaling promotes hepatic accumulation of neutrophils by promoting proliferation and development of neutrophil precursors in the bone marrow, as well as modulating hepatic recruitment of neutrophils and their functions. Antagonizing the androgen/Ar/neutrophil axis significantly mitigates LM in males. Our data thus reveal an important role of androgen in LM and suggest that androgen/Ar modulation represents a promising target for LM therapy in men.

17 March 2022 in Materials
Verified
Journal Article
Open access
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LGLinna Guo
Linna Guo
ZZZiang Zou
Ziang Zou
Ralf SmeetsRalf Smeets
Ralf Smeets
LKLan Kluwe
Lan Kluwe
PHPhilip Hartjen
Philip Hartjen
Anders HenningsenAnders Henningsen
Anders Henningsen
Ultraviolet (UV) light and non-thermal plasma (NTP) treatment are chairside methods that can efficiently improve the biological aging of implant material surfaces caused by customary storage. However, the behaviors of stem cells on these treated surfaces of the implant are still unclear. This study aimed to investigate the effects of UV light and NTP treated surfaces of titanium, zirconia and modified polyetheretherketone (PEEK, BioHPP) on the attachment and osteogenic potential of human dental pulp stem cells (DPSCs) in vitro. Machined disks were treated using UV light and argon or oxygen NTP for 12 min each. Untreated disks were set as controls. DPSCs were cultured from the wisdom teeth of adults that gave informed consent. After 24 h of incubation, the attachment and viability of cells on surfaces were assessed. Cells were further osteogenically induced, alkaline phosphatase (ALP) activity was detected via a p-Nitrophenyl phosphate assay (day 14 and 21) and mineralization degree was measured using a Calcium Assay kit (day 21). UV light and NTP treated titanium, zirconia and BioHPP surfaces improved the early attachment and viability of DPSCs. ALP activity and mineralization degree of osteoinductive DPSCs were significantly increased on UV light and NTP treated surfaces of titanium, zirconia and also oxygen plasma treated Bio-HPP (p < 0.05). In conclusion, UV light and NTP treatments may improve the attachment of DPSCs on titanium, zirconia and BioHPP surfaces. Osteogenic differentiation of DPSCs can be enhanced on UV light and NTP treated surfaces of titanium and zirconia, as well as on oxygen plasma treated Bio-HPP.

10 January 2022 in Materials
Verified
Journal Article
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LKLisa Krautwald
Lisa Krautwald
Ralf SmeetsRalf Smeets
Ralf Smeets
CSCarolin Stolzer
Carolin Stolzer
RRRico Rutkowski
Rico Rutkowski
LGLinna Guo
Linna Guo
Anders HenningsenAnders Henningsen
Anders Henningsen
The influence of UV light and non-thermal plasma on the osseointegration of yttria-stabilized zirconia implants (Y-TZP) comparing the two methods is unclear. The aim of this study was to show the influence of these methods on the osseointegration of dental zirconia implants in an animal model. A total of 54 implants were either untreated, treated with UV light (UV), or non-thermal oxygen plasma for 12 min and inserted into the parietal bones of six domestic pigs. The animals were sacrificed after a healing interval of two, four, and nine weeks. The degree of osseointegration was determined using histomorphometric determination of bone-to-implant contact values (BIC) and the bone-to-implant contact values within the retentive parts of the implants (BAFO). BIC values decreased in all groups after four weeks of healing and re-increased after nine weeks in all groups. BAFO increased significantly over time in all groups. However, there were no statistically significant differences in BIC and BAFO values between the control group and the test groups and over time. Clinical studies may follow to confirm the influence of cold plasma and UV light on the healing and survival of zirconia implants.

Verified
Journal Article
Open access
PDF file
LGLinna Guo
Linna Guo
ZZZiang Zou
Ziang Zou
Ralf SmeetsRalf Smeets
Ralf Smeets
LKLan Kluwe
Lan Kluwe
PHPhilip Hartjen
Philip Hartjen
Anders HenningsenAnders Henningsen
Anders Henningsen
Ultraviolet (UV) light and non-thermal plasma (NTP) are promising chair-side surface treatment methods to overcome the time-dependent aging of dental implant surfaces. After showing the efficiency of UV light and NTP treatment in restoring the biological activity of titanium and zirconia surfaces in vitro, the objective of this study was to define appropriate processing times for clinical use. Titanium and zirconia disks were treated by UV light and non-thermal oxygen plasma with increasing duration. Non-treated disks were set as controls. Murine osteoblast-like cells (MC3T3-E1) were seeded onto the treated or non-treated disks. After 2 and 24 h of incubation, the viability of cells on surfaces was assessed using an MTS assay. mRNA expression of vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) were assessed using real-time reverse transcription polymerase chain reaction analysis. Cellular morphology and attachment were observed using confocal microscopy. The viability of MC3T3-E1 was significantly increased in 12 min UV-light treated and 1 min oxygen NTP treated groups. VEGF relative expression reached the highest levels on 12 min UV-light and 1 min NTP treated surfaces of both disks. The highest levels of HGF relative expression were reached on 12 min UV light treated zirconia surfaces. However, cells on 12 and 16 min UV-light and NTP treated surfaces of both materials had a more widely spread cytoskeleton compared to control groups. Twelve min UV-light and one min non-thermal oxygen plasma treatment on titanium and zirconia may be the favored times in terms of increasing the viability, mRNA expression of growth factors and cellular attachment in MC3T3-E1 cells.

4 October 2017 in International Journal of Endocrinology
Verified
Journal Article
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YGYue Guo
Yue Guo
LGLinna Guo
Linna Guo
JZJun-Fei Zhu
Jun-Fei Zhu
CTChen-Yi Tang
Chen-Yi Tang
YFYun-Zhi Feng
Yun-Zhi Feng
ZHZhou Hou-De
Zhou Hou-De
Aims. To explore the differences in salivary BPI fold containing family A, member 1 (BPIFA1) concentration among type 2 diabetes mellitus (T2DM) subjects with various severities of chronic periodontitis and to determine whether BPIFA1 in saliva can be used as a potential biomarker of T2DM.Methods. Unstimulated saliva samples were collected from 44 subjects with T2DM and 44 without T2DM (NDM). Additionally, demographic data and general health parameters, including fasting blood glucose (FBG) and body mass index (BMI), were collected. We also detected full-mouth clinical periodontal parameters including probing pocket depth (PPD), clinical attachment level (CAL), bleeding index (BI), and plaque index (PLI). Salivary BPIFA1, tumor necrosis factor-α(TNF-α), and interleukin-6 (IL-6) concentrations were also detected.Results. BPIFA1 in saliva was detected at relatively high levels. T2DM subjects had decreased salivary BPIFA1 concentrations (P=0.031). In T2DM subjects with nonperiodontitis or severe periodontitis, the level of BPIFA1 was significantly lower compared with that of NDM. Salivary TNF-αconcentration displayed a similar trend to BPIFA1 in the NDM group.Conclusions. BPIFA1 protein is rich in saliva and might be used as a potential predictive biomarker of T2DM, especially in patients with severe periodontitis and nonperiodontitis. This trial is registered withChiCTR-ROC-17010310.