Objective:To investigate the value of flattening filter-free (FFF) mode in postoperative deep inspiration breath-hold (DIBH) intensigy-modulated radiotherapy for left breast cancer.Methods:A retrospective case series study was conducted. Clinical data of 21 patients with left breast cancer who underwent DIBH intensity-modulated radiotherapy after modified radical surgery in Meizhou People's Hospital from January 2021 to December 2022 were retrospectively analyzed. On the DIBH-mode CT of each patient, the 7-field intensity-modulation plan was designed using the plan developed in the 6 MV FFF-mode (FFF group) or the plan developed in the 6 MV flattening filter (FF)-mode (FF group). The target areas and organs at risk, dosimetric and biological parameters, and dose validation results were compared between the two plans.Results:Twenty-one patients were female with the age [ M ( Q1, Q3)] of 47 years old (32 years old, 61 years old). The percentage of target areas receiving 95% of the prescribed dose (V 95%) was (95.9±0.8)% and (95.7±1.9)% in the FF and FFF groups ( t = 2.98, P = 0.089), and the maximum dose was (5 401±251) cGy and (5 424±201) cGy ( t = 2.85, P = 0.181), the fitness indices were 0.88±0.05 and 0.87±0.06 ( t = 0.32, P = 0.562), the homogeneity indices were 1.06±0.01 and 1.07±0.02 ( t = 2.91, P = 0.009), the equivalent uniform doses (EUD) were (51.81±0.21) Gy and (51.97±0.20) Gy ( t = 0.51, P = 0.309), and the tumor control probability (TCP) was (99.68±0.01)% and (99.61±0.02)% ( t = 0.81, P = 0.560). The plans of the FFF group and the FF group were compliant, and the doses of all organs at risk to be irradiated were within the clinically acceptable range, and the radiation doses in the FFF group in the left lung [5 Gy irradiated volume (V 5 Gy), mean dose (D mean), EUD and normal tissue complication rate (NTCP)], right lung (V 5 Gy and D mean), heart (V 10 Gy, D mean, EUD and NTCP), and right breast (V 5 Gy, D mean and EUD) were differently lower than those in the FF group, and the differences were statistically significant (all P < 0.05). The monitor units in the FFF and FF groups were (984±132) MU and (751±145) MU ( t = -1.25, P < 0.001), and the total beam-on time was (1.4±0.3) min and (2.2±0.4) min ( t = 0.68, P < 0.001); individual field beam-on time was (12±7) s and (16±10) s ( t = 2.68, P = 0.001), and the beam-on time for each field in patients of the FFF group was less than 25 s; γ pass rates were (97.1±2.8)% and (97.6±2.1)% ( t = 0.59, P = 0.484). Conclusions:In the intensity-modulated radiotherapy of left breast cancer, the radiation dose of the energy to the critical organs in FFF mode is lower and has higher dose rate and shorter treatment time. FFF combined with DIBH technique has positive clinical significance in the intensity-modulated radiotherapy of breast cancer.

Laboratory animals provide an important experimental resource for life science research,and their uniformity plays a key role in the accuracy and reliability of the experimental result.Genetic quality testing of laboratory animals is thus essential to evaluate the genetic quality of laboratory animals.Progress in modern biotechnology has led to improvements in the method of genetic testing of experimental animals.Single nucleotide polymorphisms,as molecular markers,have been widely used in genetic testing of laboratory animals,and method for their detection in laboratory animals have been updated,in line with biotechnology advances.In this paper,we review current research progress and the application of SNP detection method for genetic quality testing of laboratory animals,and discuss the advantages and disadvantages of various detection method,with a view to providing a reference basis for genetic quality testing of laboratory animals.

Laboratory animals provide an important experimental resource for life science research,and their uniformity plays a key role in the accuracy and reliability of the experimental result.Genetic quality testing of laboratory animals is thus essential to evaluate the genetic quality of laboratory animals.Progress in modern biotechnology has led to improvements in the method of genetic testing of experimental animals.Single nucleotide polymorphisms,as molecular markers,have been widely used in genetic testing of laboratory animals,and method for their detection in laboratory animals have been updated,in line with biotechnology advances.In this paper,we review current research progress and the application of SNP detection method for genetic quality testing of laboratory animals,and discuss the advantages and disadvantages of various detection method,with a view to providing a reference basis for genetic quality testing of laboratory animals.

Diabetes can lead to a variety of complications, such as chronic wound (diabetic foot), which is one of the important causes of death for patients with diabetes. Unfavorable factors such as high blood glucose, high level of oxidative stress and inflammation, and susceptibility to infection lead to difficult healing and even worsening of diabetic chronic wounds. Due to the advantages of high water content, good biocompatibility, and tunable physicochemical properties, the hydrogels have become hot-spot materials in wound dressing research. Compared with the traditional dressings such as gauze, the hydrogel dressings can provide a moist environment that is beneficial for wound healing. By loading of bioactive components and modulation of compositions and structures of hydrogels, the hydrogel dressings can be endowed with excellent tissue adhesion, antibacterial ability, anti-oxidation, and inflammation regulation effect, etc., and thus show great prospects in wound dressing applications. Based on the characteristics of hydrogel materials and microenvironment of diabetic chronic wound, this review summarized the research advances on new multifunctional hydrogel dressings for the treatment of diabetic chronic wounds in recent years, and discussed the drawbacks of current hydrogel dressings with prospects proposed.

OBJECTIVETo investigate the mechanisms underlying the ability ofheparin-treated dendritic cells (DCs) to promote Th0 to Th1 differentiation in chronic hepatitis B (CHB).

METHODSPeripheral blood mononuclear cells (PBMCs) were isolated from CHB patients and cultured in RPMI-1640 with recombinant GM-CSF and IL-4 with or without heparin to obtain DCs for study. The levels of Toll-like receptors (TLRs) on the DCs were measured using FACS and qPCR techniques.DC subsets with high expression of TLRs were selected for analysis of functional changes by treatment with the corresponding TLR-siRNA. The CD4+ T cell subpopulation was purified from peripheral blood by Dynal immunomagnetic beads, and then the production of IL-12 by DCs in the presence of poly(I:C) or R848 and ofIFN and IL-4 by Th cells co-cultured with DCs was evaluated by ELISA. The t-test was used for statistical analysis.

RESULTSTLR3 expression, and not expression of TLR 7 or TLR8,was significantly increased in heparin-treated DCs as compared to levels detected in the DCs without heparin treatment (t =2.849,P less than 0.05;t =3.027,P less than 0.05). The level of IL-12 produced by heparin-treated DCs stimulated with poly(I:C) was obviously higher than that produced by DCs without heparin treatment and stimulated with poly(I: C) (t =8.68,P less than 0.01) or with R848 (t =19.01,P less than 0.01). However, the IL-12 production by TLR3-siRNA transfected-DCs was significantly reduced (t =31.49, P less than 0.01).When Th cells from allogenic patients with CHB were co-cultured with the TLR3-siRNA transfectedDCs, the frequency ofCD4+ IFN+ cells was significantly reduced (1.64+/-0.57% vs.6.31+/-0.88%,P less than 0.01),as was the capability of Thl to generate IFNg (t =20.83,Pless than 0.01).

CONCLUSIONHeparin may have up-regulated the TLR3 expression level of DCs, and sequentially promoted Th0 to Th1 differentiation.

CD4-Positive T-Lymphocytes ; cytology ; Cell Differentiation ; Coculture Techniques ; Dendritic Cells ; cytology ; Granulocyte-Macrophage Colony-Stimulating Factor ; pharmacology ; Heparin ; pharmacology ; Hepatitis B, Chronic ; immunology ; Humans ; Interferon-gamma ; metabolism ; Interleukin-12 ; metabolism ; Interleukin-4 ; pharmacology ; Monocytes ; cytology ; Recombinant Proteins ; pharmacology ; Toll-Like Receptor 3 ; metabolism

Objective To investigate the possibility of hair follicle reformation induced by hair follicle bulb cells implanted into collagen/chitosan porous scaffolds in vivo, and to observe the angiogenesis in implanted scaffolds.Methods Hair follicle bulb cells obtained by enzyme digestion from the hack skin of C57BL/6J mice were implanted into collagen/chitosan porous scaffolds followed by 2-week organotypie culture.Then,these collagen/chitosan porous scaffolds were transplanted subcutaneously into the dorsal skin of nude mice.Those nude mice transplanted with empty collagen/chitosan porous scaffolds served as the controls.The growth of hair was observed with naked eyes.Six weeks after the transplantation,skin samples were obtained from the recipient site and subjected to histological examination.Results Five weeks after the transplantation,hair growth was observed in the dorsal skin of nude mice.Six weeks later,histological examination revealed fully differentiated hair follicles and vessel-like structures in the center of collagen/chitosan porous scaffolds.However,the transplantation with empty collagen/chitosan porous scaffolds failed to elicit the same response.No hair or follicles were observed in the control mice alpng with small number of vessel-1ike structures.Con-clusions Hair follicle bulb ceils implanted into collagen/chitosan porous scaffolds in vivo could induce hair follicle reformation and promote the formation of vessel-like structure in the scafffold center.

BACKGROUND: Contacting with blood, most of polymer materials lead to different extents of blood coagulation, which limits their clinical application. Therefore, developing polymer materials with excellent anticoagulant property has become a key to clinical study of bioartificial liver materials.OBJECTIVE: To in vitro detect the blood dompatibility of polyacrylamide grafted polypropylene (PP) membrane (PP-g-AAm), a novel artificial liver reactor material.METHODS: Prior to and after modification, hemolytic test, prothrombin time and activated partial thromboplastin time tests of PP membrane were performed; blood platelet CD62P and CD63 expression rates were determined by flow cytometry, and platelet adhesion on PP and PP-g-AAm membranes by scanning electron microscopy.RESULTS AND CONCLUSION: The hemolysis ratio of PP and PP-g-AAm membranes was 1.32% and 1.46%, respectively.Compared with PP-g-AAm membrane, prothrombin time and activated partial thromboplastin time of PP membrane weremarkedly shorter (P < 0.05). CD62P and CD63 expression rates in the PP-g-AAm membrane were significantly lower than PP membrane (P < 0.05). Scanning electron microscopy results revealed that there were obvious changes of platelets adhering to these two membranes, but platelets adhering to PP-g-AAm membrane were fewer than PP membrane. These results indicate that PP-g-AAm membrane exhibits good blood compatibility.

BACKGROUND: Membrane materials of bioreactor have exchange of substance and good physiochemical characteristics as well as good biocompatibility.OBJECTIVE: To evaluate the biocompatibility of interface of human hepatocyte/microporous polypropylene, i.e. graft modified microporous polypropylene semipermeable ultrafiltration membrane (MPP).DESIGN, TIME AND SETTING: Animal observation was performed at the Organ Transplantation Center, Ruijin Hospital of Shanghai Jiao Tong University Medical School and Polymers Institute of Zhejiang University between September 2005 and October 2007.MATERIALS: The microporous polypropylene ultrafiltration plane thin membranes, 0.2 μm diameter, M<,r> 50 000-100 000 molecular blockage, were used. Photochemical graft polymerization modification technique was adopted to graft hydrophilic acrylamide group through chemical bonds on MPP surface and succeeded in constructing an interface of human hepatocyte/microporous polypropylene, i.e. bioreactor membrane of bioartificial liver, graft modified MPP.METHODS: The biocompatibility of modified MPP was evaluated by hemolysis test, cytotoxicity test, acute systemic toxicity test, pyrogen test, skin sensitization and percutaneous stimulation test according to the requirements and biological evaluation criteria of medical device of ISO10993-1:1992.MAIN OUTCOME MEAURES: The experimental results of hemolysis, cytotoxicity, general acute toxicity, pyrogen, skin sensitization and percutaneous stimulation of modified MPP.RESULTS: The hemolytic rate of modified MPP was 1.90% (<5%), which showed that modified MPP did not lead to hemolysis. The extract solution of modified MPP exhibited no significant inhibition on the proliferative activity of L929 cells. At 24, 48 and 72 hours after MPP injection, no mice death, significant changes in body mass, or acute systemic toxicity were observed, such as ptosis, dyspnea, eyanosis, abdominal stimulation, diarrhea, decreased movement or tremor. In rabbit pyrogen test, the body temperature changed in a range from -0.2 to 0.4, which was consistent with the evaluation criteria of biomedical materials without pyrogen. Only one case was found with very slight erythema in skin sensitization test; its integral was 1 and primary stimulation index was 0.25 (<0.4), and the primary stimulation index of percutaneous stimulation test was 0.2; the average primary stimulation index was 0.068, indicating that modified MPP had no skin irritation.CONCLUSION: Modified MPP has no haemolytieus, cytotoxicity, pyrogenicity or skin sensitization, suggesting good biocompatibility by photochemical graft acrylamide on the surface of MPP.

BACKGROUND: Hepatocyte/polymer interface with good biocompatibility is the key factor in bioreactor design andconstruction, however, bioreactor used in the clinical practice currently is not an ideal one.OBJECTIVE: To establish human hepatocyte compatible polypropylene interface and to lay a foundation for establishingbioartificial liver reactor with polypropylene hollow fiber.DESIGN, TIME AND SETTING: The comparative observation, cell compatibility experiment was performed betweenFebruary and October 2003 at Shanghai Jiao Tong University, Shanghai, China.MATERIALS: Polypropylene Photochemical graft polymerization modification technique was used to graft hydrophilicacrylamide groups on the surface of polypropylene membrane by chemical bonds to form modified polypropylenemembrane.METHODS: L02 human hepatoeytes were seeded on polypropylene membrane, modified polypropylene membrane andpolystyrene membrane, and polystyrene membrane was used as normal control.MAIN OUTCOME MEASURES: Static water contact angle of polypropylene membrane before and after graftmodification; morphology, adherent rate and proliferation activity of L02 human hepatocytes on different material surfaces.RESULTS: Static water contact angle after polypropylene membrane graft modification was smaller than that before graftmodification (P < 0.05). The adherent rate of L02 human hepatocytes on the surface of modified polypropylene membranewas 0, and the proliferation activity of them, which grew as spherical aggregates, was markedly higher than that of cells onpolystyrene membrane and polypropylene membrane without graft modification.CONCLUSION: Grafting polyacrylamide on the surface of polypropylene can establish good interface of L02 humanhepatocytes/polypropylene and form hepatocyte spherical aggregates through simple static culture.

Three-dimensional cell scaffolds play an important role in tissue engineering. They can modulate cell response and guide the regeneration of tissues. Injectable scaffolds can mimic the chemical and physical environments of natural extracellular matrix, and can be easily applied in clinic with the merits of minor or nonsurgical operations. Hence, special care should be given to the use of this kind of scaffolds in tissue engineering hydrogels, and composites with other fillers have been used as a basic component to construct the injectable scaffolds. Most of these injectable scaffolds are applied to repair bone and cartilage. Experimental results have development of the injectable scaffolds in recent years. The advantages and disadvantages are discussed with the development of the injectable scaffolds in recent years. The advantages and disadvantages are discussed with the suggestions for future development.
Absorbable Implants ; Biocompatible Materials ; Bone and Bones ; physiology ; Cartilage ; physiology ; Guided Tissue Regeneration ; Humans ; Hydrogels ; Tissue Engineering ; methods ; Tissue Scaffolds