The effect of increasing the gaps between the front teeth on torque and intrusion control of the incisors for anterior retraction with clear aligners: a prospective study.

OBJECTIVE: To investigate the effect of sequential distalization on increasing gaps in the maxillary anterior teeth, focusing on the control of torque and three-dimensional teeth movement during anterior retraction with clear aligners in extraction cases. METHODS: We recruited 24 patients who were undergoing extraction bilateral maxillary first premolars with clear aligners. According to a predetermined increment in the spaces between the maxillary anterior teeth, the patients were divided into three groups: those with no gap (9 cases), a 0.5 mm gap (6 cases) and a 1.0 mm gap (9 cases). In each group, a 2.0 mm en-mass retraction was applied on the anterior teeth. Plaster casts of the upper full dentition were obtained both before and after a 2 mm retraction. The palatal folds were used to overlap each pair of models. The three-dimensional movement of the teeth and the change of torque for the anterior teeth were subsequently analyzed using Geomagic Studio 2014 software. RESULTS: The change in torque in the groups with added gaps was significantly smaller than that in the group with no gaps (P < 0.05). There was no significant difference in this respect when comparing the group with a 0.5 mm gap added to the group with a 1.0 mm gap was added (P > 0.05). In the labial-lingual and vertical directions, the displacements of the central and lateral incisors were smaller in the groups with additional gaps compared to those in the groups without gaps (P < 0.05). However, there was no significant difference observed when comparing the group with a 0.5 mm added gap to the group with a 1.0 mm added gap (P > 0.05). Then, a comparison was made between the displacement of the second premolar to the second molar in the mesial-distal direction across all groups. The study revealed that the anchorage molars in the group without gaps demonstrated significantly smaller displacement compared to those in the group with additional gaps (P < 0.05). CONCLUSION: Advantages were observed in controlling the torque of the anterior teeth and achieving a desired pattern closer to normal bodily movement by sequentially distalizing the maxillary anterior teeth gaps. Increasing the gaps between the maxillary anterior teeth also resulted in improved control of the vertical direction of the anterior teeth. However, this retraction strategy necessitates substantial protection of the anchorage molars.

Dual Biosignal-Functional Injectable Microspheres for Remodeling Osteogenic Microenvironment.

Bone defect regeneration depends on the population and lifespan of M2 macrophages, which are regulated by dual signals generated by the "physical" spatial configuration of biological tissues and "molecular" chemokines. Herein, inspired by the reprogramming of macrophages, immunoengineered porous microspheres are constructed to accelerate bone repair through the regulation of both "physical" and "molecular" signals. The porous structure of injectable poly (l-lactic acid) (PLLA) microspheres prepared by the microfluidic technique provides a "physical signal" for osteogenic differentiation. Additionally, interleukin (IL)-4-loaded liposomes (Ls) are modified on PLLA microspheres through amide bonds to produce IL-4/Ls/PLLA microspheres, providing a "molecular signal" in stimulating the differentiation of macrophages to M2 type. It is confirmed that IL-4/Ls/PLLA microspheres could induce M2-macrophages polarization and potentiate osteoblast proliferation and differentiation while coculturing with macrophages and osteoblasts in vitro. Besides, IL-4/Ls/PLLA microspheres are proved to promote bone defect regeneration by inducing the conversion of M1 macrophages to M2 through dual biosignal-functional regulation in both the calvaria defect and maxillary sinus defect models. Overall, the immuno-reprogrammed IL-4/Ls/PLLA microspheres achieve the precise immuno-reprogramming of macrophages by dual biosignal-functional regulation. This immune reengineering strategy paves a way for clinical bone defect treatment.

Roles of PKAc1 and CRE1 in cellulose degradation, conidiation, and yellow pigment synthesis in Trichoderma reesei QM6a.

PURPOSE: This study aimed to reveal the roles of the protein kinase A catalytic subunit 1 (pkac1) and carbon catabolite repressor cre1 genes in cellulase production by Trichoderma reesei wild-type strain QM6a. Our strategy might be useful to construct a high-yielding cellulase strain for its wide application. METHODS: This paper describes cellulase activity, plate conidiation, and yellow pigment synthesis assays of QM6a with the disruption of pkac1 and cre1. RESULTS: Deletion of pkac1 (Δpkac1) had no effect on cellulase production or transcript levels of major cellulase genes in the presence of cellulose. Disruption of cre1 (Δcre1) resulted in a remarkable increase in cellulase production and expression of the four major cellulase genes. Double disruption of pkac1 and cre1 significantly improved enzyme activity and protein production. The double disruption also resulted in a significant reduction in yellow pigment production and abrogated conidial production. CONCLUSION: Double deletion of pkac1 and cre1 led to increased hydrolytic enzyme production in T. reesei using cellulose as a carbon source.

[Effect of a Simple Home-Based Oral Care Regimen on Oral Mucositis in Patients With Oral Cavity and Nasopharyngeal Cancer: A Quasi-Experimental Study].

BACKGROUND: The majority of patients with oral cavity and nasopharyngeal cancer experience severe oral mucositis during concurrent radiochemotherapy. The effectiveness of routine nursing education remains limited. PURPOSE: To evaluate the effect of a simple home-based oral care regimen on oral mucositis. METHODS: A double-group quasi-experimental design was adopted in this study. The participants were all newly diagnosed patients with oral cavity and nasopharyngeal cancer who were scheduled to receive concurrent radiochemotherapy in a northern medical center. A total of 31 patients in the experimental group and 32 patients in the control group were enrolled as participants. The control group received routine care, while the experimental group received an additional six- to seven-week two-way interactive home-based oral care regimen. The measurement tools included a plaque record and oral assessment guide (OAG) implemented twice during the study period. Study data were collected at 8 time points, including before treatment, at 1-5 weeks of treatment, at the end of treatment, and at one-month post-treatment. Data analysis was performed using two-way repeated measures ANCOVA. RESULTS: After controlling for OAG score, nutrition, age, living habits, and oral hygiene, the development of mucositis was found to be significantly slower in the experimental group than in the control group during the traumatic phase (effect of group: F = 11.1, p < .01; effect of group x time: F = 3.5, p = .01). However, both groups reported a statistically similar rate of improvement during the repair phase (effect of group and group x time: F = 0.19, p = .67). CONCLUSIONS / IMPLICATIONS FOR PRACTICE: The simple home-based oral care regimen introduced in this study may be used to improve traumatic oral mucositis in patients with oral cavity and nasopharyngeal cancer. It is recommended that even after the completion of radiotherapy, medical staffs should continue to strengthen patients' execution of proper oral care to maintain the positive effect until the mucositis has abated.

Trichoderma reesei ACE4, a Novel Transcriptional Activator Involved in the Regulation of Cellulase Genes during Growth on Cellulose.

The filamentous fungus Trichoderma reesei is a model strain for cellulase production. Cellulase gene expression in T. reesei is controlled by multiple transcription factors. Here, we identified by comparative genomic screening a novel transcriptional activator, ACE4 (activator of cellulase expression 4), that positively regulates cellulase gene expression on cellulose in T. reesei. Disruption of the ace4 gene significantly decreased expression of four main cellulase genes and the essential cellulase transcription factor-encoding gene ace3. Overexpression of ace4 increased cellulase production by approximately 22% compared to that in the parental strain. Further investigations using electrophoretic mobility shift assays, DNase I footprinting assays, and chromatin immunoprecipitation assays indicated that ACE4 directly binds to the promoter of cellulase genes by recognizing the two adjacent 5'-GGCC-3' sequences. Additionally, ACE4 directly binds to the promoter of ace3 and, in turn, regulates the expression of ACE3 to facilitate cellulase production. Collectively, these results demonstrate an important role for ACE4 in regulating cellulase gene expression, which will contribute to understanding the mechanism underlying cellulase expression in T. reesei. IMPORTANCET. reesei is commonly utilized in industry to produce cellulases, enzymes that degrade lignocellulosic biomass for the production of bioethanol and bio-based products. T. reesei is capable of rapidly initiating the biosynthesis of cellulases in the presence of cellulose, which has made it useful as a model fungus for studying gene expression in eukaryotes. Cellulase gene expression is controlled through multiple transcription factors at the transcriptional level. However, the molecular mechanisms by which transcription is controlled remain unclear. In the present study, we identified a novel transcription factor, ACE4, which regulates cellulase expression on cellulose by binding to the promoters of cellulase genes and the cellulase activator gene ace3. Our study not only expands the general functional understanding of the novel transcription factor ACE4 but also provides evidence for the regulatory mechanism mediating gene expression in T. reesei.

Tooth transplantation with a ß-tricalcium phosphate scaffold accelerates bone formation and periodontal tissue regeneration.

OBJECTIVES: Although tooth transplantation is a useful treatment option as a substitute for a missing tooth, transplantation to a narrow alveolar ridge is not feasible. In this study, we tested a tissue engineering approach simultaneously with tooth transplantation using a scaffold or a combination with cells to accelerate bone formation and periodontal tissue regeneration. MATERIALS AND METHODS: Bone marrow mononuclear cells (BM-MNCs) were harvested from C57BL/6J mice. The upper first or the second molar of 3-week-old C57BL/6J mice and a ß-tricalcium phosphate (ß-TCP) scaffold were transplanted with BM-MNCs (MNC group) or without BM-MNCs (ß-TCP group) into the thigh muscle of syngeneic mice. The tooth alone was also transplanted (control group). After 4 weeks, the transplants were harvested and analyzed. RESULTS: Bone volume was significantly larger in the MNC and the ß-TCP groups than that in the control group, and the newly formed bone was observed on the lateral wall of the root. Compared with the control group, the MNC group showed a larger trabecular thickness and fractal dimension. CONCLUSION: This study showed accelerated bone formation and periodontal tissue regeneration when tooth transplantation was performed with a ß-TCP scaffold. BM-MNCs may accelerate bone maturation, while the effect on bone formation was limited.

Healing outcomes of open versus closed flap procedures for collagen membrane coverage following immediate dental implant placements with simultaneous guided tissue regeneration.

OBJECTIVE: To compare the outcomes of open healing to complete closure for collagen membrane coverage for immediate implant placements with simultaneous guided bone regeneration (GBR) in two retrospective cohorts. METHODS: The subjects included 118 patients who received Bio-Gide® collagen membrane coverage for immediate implant placements and GBR in 20 anterior and 98 posterior teeth. For 58 patients, gingival flaps were released to achieve full coverage of collagen membrane (CC group). For 60 patients, no efforts were made to release the gingival flaps and collagen membrane was left exposed for open healing (OH group). Antibiotics and analgesics were prescribed for 7 days after surgery. The width of crestal open wounds were measured after surgery (W0), and at 1, 2 and 16 weeks (W16). Changes in bone mass were assessed by cone-beam computed tomography after implant placement and again at W16. Gingival and bone tissues over the implant cover screws were harvested and assessed for 16 patients in the OH group at W16. RESULTS: No wound dehiscence occurred in the CC group from W0 to W16. Both the vertical and horizontal bone dimension changes were not significantly different between the OH and CC group. For the OH group, soft tissue was completely healed at W16 when the initial wound widths were ≤6 mm. For those with initial wound widths ≥ 7 mm, the cover screws were exposed in 5/16 patients at W16 but did not affect the final restorations. Tissue staining showed keratinized mucosa and new bone formation above the dental implant in the OH group. CONCLUSION: Open healing achieved healing outcomes similar to those of complete closure for collagen membrane coverage following immediate implant placements. CLINICAL SIGNIFICANCE: For immediate implant placement requiring bone grafting and collagen membrane coverage, it is unnecessary to release the gingival flaps or use tissue grafts to achieve full coverage of the crestal wounds. Open healing with exposed membrane could achieve similar outcomes with less pain and swelling.

Precisely targeted drug delivery by mesenchymal stem cells-based biomimetic liposomes to cerebral ischemia-reperfusion injured hemisphere.

The precise and targeted delivery of therapeutic agents to the lesion sites remains a major challenge in treating brain diseases represented by ischemic stroke. Herein, we modified liposomes with mesenchymal stem cells (MSC) membrane to construct biomimetic liposomes, termed MSCsome. MSCsome (115.99 ± 4.03 nm) exhibited concentrated accumulation in the cerebral infarcted hemisphere of mice with cerebral ischemia-reperfusion injury, while showing uniform distribution in the two cerebral hemispheres of normal mice. Moreover, MSCsome exhibited high colocalization with damaged nerve cells in the infarcted hemisphere, highlighting its advantageous precise targeting capabilities over liposomes at both the tissue and cellular levels. Leveraging its superior targeting properties, MSCsome effectively delivered Dl-3-n-butylphthalide (NBP) to the injured hemisphere, making a single-dose (15 mg/kg) intravenous injection of NBP-encapsulated MSCsome facilitate the recovery of motor functions in model mice by improving the damaged microenvironment and suppressing neuroinflammation. This study underscores that the modification of the MSC membrane notably enhances the capacity of liposomes for precisely targeting the injured hemisphere, which is particularly crucial in treating cerebral ischemia-reperfusion injury.

The effect of space arrangement between anterior teeth on their retraction with clear aligners in first premolar extraction treatment: a finite element study.

INTRODUCTION: Clear aligner therapy has become increasingly popular in recent years, although it has encountered several difficulties in premolar extraction treatment. These difficulties include anterior dentition, lingual tipping and extrusion. The design of the present clinical scheme usually set a tiny space between the anterior teeth before retraction in order to obtain an ideal outcome. The objective of our research was to analyze the effect of the existing spaces during retraction. METHODS: Models including maxillary dentition without first premolars, maxilla, periodontal ligaments, gingiva, or aligners were constructed and imported to an ANSYS workbench. Five groups of models were created: without spaces and with 0.25, 0.50, 0.75 and 1.00 mm spaces between the anterior dentition. A 0.20 mm retraction step was applied to all the groups. RESULTS: As the spaces between the anterior dentition increased, the bowing effect of the aligner caused by the passive forces decreased gradually. Accordingly, the degree of extrusion of the anterior dentition was alleviated significantly, while sagittal movement was reduced. However, the overall movement tended to be a bodily displacement rather than tipping. Meanwhile, maximum Von Mises stress of the periodontal ligaments (PDLs) was markedly decreased. CONCLUSION: These analyses indicate that spaces between the anterior dentition during anterior retraction are beneficial for decreasing the tendency for extrusion of the anterior dentition and require provision of anchorage. Appropriate spaces can be designed to lest the lingual tipping and extrusion effect of the anterior teeth while simultaneously reducing the maximum stresses on PDLs.

Sustained delivery of IL-1Ra from pluronic F127-based thermosensitive gel prolongs its therapeutic potentials.

PURPOSE: Pluronic F-127 (PF127) has previously shown to prolong the sustained release of various proteinous drugs and their serum half-lives. Subsequently, we have extended this approach to look at in vitro release, in vivo efficacy and pharmacokinetics of interleukin-1 receptor antagonist (IL-1Ra). METHODS: Various concentrations of PF127 gels were prepared using cold method. In vitro drug release kinetic studies were performed using membraneless dissolution method. Stability of IL-1Ra was assessed by SDS-PAGE. In vivo studies and in vivo bioactivity of IL-1Ra were also performed on wistar rats. RESULTS: IL-1Ra loaded PF127 gels showed in vitro sustained release of IL-1Ra, depending on the concentration of gel used. SDS-PAGE confirmed the stability of protein during its in vitro release. PF127 gel also exhibited prolonged release of IL-1Ra in rats as compared to that of IL-1Ra aq. solution. In vivo bioactivity of IL-1Ra loaded in gel was confirmed by its ability to inhibit IL-1ß-stimulated induction of IL-6. CONCLUSIONS: When compared directly, IL-1Ra loaded PF127 gel exhibited prolonged in vitro and in vivo release, greater efficacy to induce hypoglycemia and inhibited IL-1ß-stimulated production of IL-6 as compared to IL-1Ra aq. solution. We believe that this methodology for sustained delivery of IL-1Ra probably be suitable for the convenience of patients to achieve desired therapeutic potentials without exceeding dose limits and frequent administration.

Waterproof, breathable and infrared-invisible polyurethane/silica nanofiber membranes for wearable textiles.

Waterproof and breathable membranes, which have great potential in applications such as membrane distillation, self-cleaning, and multifunctional clothing, have attracted a lot of attention due to their superior performance. Superhydrophobic and infrared-invisible polyurethane (PU)/silica (SiO2) nanofiber microporous membranes were prepared by facile electrospinning and a hydrothermal-assisted sol-gel method. Compared with pure PU nanofiber membranes, silica nanoparticles act as an adhesion layer, which can provide the rough surface and low surface energy of fibrous membranes. Therefore, the grafted PU/SiO2 nanofiber membrane was endowed with a good superhydrophobic effect, and its water contact angle (WCA) reached 161°. The nanofiber membrane exhibited comfortable waterproof and breathable properties, in which the air permeability and water vapor transfer rate was 5.18 mm s-1 and 7.85 kg m-2 d-1, respectively. When the PU/SiO2 nanofiber membrane was irradiated by infrared light, the surface of the fiber membrane showed a green, low-temperature state. These waterproof and breathable nanofiber membranes with superhydrophobic properties could be used in anti-icing, outdoor concealment, and camouflage applications.

Tissue Engineering with Compact Bone-Derived Cell Spheroids Enables Bone Formation around Transplanted Tooth.

BACKGROUND: Although tooth transplantation is a desirable treatment option for congenital defects of permanent teeth in children, transplantation to a narrow alveolar ridge is not feasible. In this study, we investigated the possibility of bone tissue engineering simultaneously with tooth transplantation to enhance the width of the alveolar bone. METHODS: Bone marrow mononuclear cells or cortical bone-derived mesenchymal stromal cell spheroids were seeded onto atelocollagen sponge and transplanted with freshly extracted molars from mice of the same strain. New bone formation around the tooth root was evaluated using micro-computed tomography and histological analysis. Tooth alone, or tooth with scaffold but without cells, was also transplanted and served as controls. RESULTS: Micro-computed tomography showed new bone formation in the furcation area in all four groups. Remarkable bone formation outside the root was also observed in the cortical bone-derived mesenchymal stromal cell group, but was scarce in the other three groups. Histological analysis revealed that the space between the new bone and the root was filled with collagen fibers in all four groups, indicating that the periodontal ligament was maintained. CONCLUSION: This study demonstrates the potential of simultaneous alveolar bone expansion employing bone tissue engineering approach using cortical bone-derived mesenchymal stromal cell spheroids for tooth transplantation. The use of an orthotopic transplantation model may further clarify the feasibility and functional recovery of the transplanted tooth over a longer period.

Exploration of possible binding sites of nanoparticles on protein by cross-linking chemistry coupled with mass spectrometry.

For the first time, the possible binding site of nanoparticles on protein was revealed by cross-linking chemistry coupled with mass spectrometry. The peptides located very close to the poly(acrylic acid) (PAA)-coated Fe(3)O(4) nanoparticles (NPs) during interaction with human serum albumin (HSA) were cross-linked to the surface of NPs. Following protease digestion, the attached peptides were cleaved off the particle surface and identified by matrix-assisted laser desorption/ionization-time-of-flight-mass spectrometry (MALDI-TOF-MS). The peptides were found to be part of the so-called drug binding site 2 of HSA; and the competitive binding to HSA between the corresponding drug, ibuprofen, and the NPs was observed. Our results demonstrated that cross-linking chemistry coupled with MS was a quick and simple method for locating the possible binding sites of NPs on protein. Information on NP-protein binding interface will benefit the study of how the interactions are governed by the physicochemical properties of NPs, for guiding the design of functional bionano constructs. It can also help to predict the biological consequence of protein adsorption on NPs, for obtaining more knowledge on nanotoxicity.

Transcriptomic analysis of cells in response to EV71 infection and 2Apro as a trigger for apoptosis via TXNIP gene.

BACKGROUND: Enterovirus 71 (EV71) is the main pathogen of hand-foot-mouth disease (HFMD) and sometimes causes several neurological complications. However, the underlying mechanism of the host response to the virus infection remains unclear. OBJECTIVE: To reveal the cell-specific transcriptional response of cultured RD cells following infection with EV71, and better understand the molecular mechanisms of virus-host interactions. METHODS: The RD cells were infected with or without EV71 for 24 h, and then transcriptome sequencing and qRT-PCR were performed to analyze the transcriptome difference of functional genes. RESULTS: More than 15000 genes were identified in transcriptome sequencing. In comparison with uninfected RD cells, 329 DEGs were identified in cells infected with EV71. GO and KEGG pathway enrichment analysis showed that most of the DEGs were related to DNA binding, transcriptional regulation, immune response and inflammatory response, apoptosis inducing factors and enriched in JAK-STAT and MAPK signaling pathways. TXNIP (thioredoxin-interacting protein) gene was further demonstrated to play an important role participating in cellular apoptosis induced by EV71, and the apoptosis and death mediated by TXNIP during EV71 infection was triggered by viral 2A protease (2Apro), not 3C protease (3Cpro). CONCLUSION: Our study demonstrated that RD cells have a significant response to EV71 infection, including immune response and apoptosis. 2Apro might be a key inducer relative to the cellular apoptosis and death mediated by TXNIP during EV71 infection. These data would contribute to preferably understand the process at the molecular level and provide theoretical foundation for diagnosis and treatment of EV71-related diseases.

Effect of AcrySof versus silicone or polymethyl methacrylate intraocular lens on posterior capsule opacification.

OBJECTIVE: To investigate the effect of AcrySof intraocular lenses (IOLs) on the development of posterior capsule opacification (PCO) compared with silicone or polymethyl methacrylate (PMMA) IOLs for patients with senile cataracts. DESIGN: Meta-analysis of randomized controlled trials (RCTs). PARTICIPANTS: Patient data from previously reported RCTs. METHODS: A comprehensive literature search was performed using the Cochrane Collaboration methodology to identify RCTs comparing AcrySof with silicone or PMMA IOLs in patients with senile cataract. A meta-analysis was performed on the results of RCTs. MAIN OUTCOME MEASURES: Posterior capsule opacification score, neodymium:yttrium-aluminum-garnet (Nd:YAG) capsulotomy rate, and best-corrected visual acuity (BCVA) of 0.5 or better after cataract surgery. RESULTS: In total, 10 RCTs involving 1202 eyes with senile cataract were included in this meta-analysis. The results suggested that AcrySof had lower PCO scores than round-edged silicone IOLs (standard mean difference [SMD], -0.25; 95% confidence interval [CI], -0.42 to -0.08; P = 0.003) and a somewhat higher PCO score than sharp-edged silicone IOLs (SMD, 0.48; 95% CI, 0.29-0.68; P<0.00001). AcrySof had a lower Nd:YAG capsulotomy rate than round-edged silicone IOLs (odds ratio [OR], 0.29; 95% CI, 0.14-0.62; P = 0.001) and did not differ from sharp-edged IOLs (OR, 1.72; 95% CI, 0.23-13.13; P = 0.60). AcrySof had a lower PCO score (SMD, -1.07; 95% CI, -1.29 to -0.85; P<0.00001) and a lower Nd:YAG capsulotomy rate (OR, 0.09; 95% CI, 0.04-0.20; P<0.00001) than round-edged PMMA IOLs. Furthermore, there was no significant difference in BCVA between AcrySof and round-edged silicone IOLs (OR, 2.28; 95% CI, 0.66-7.82; P = 0.19) or PMMA IOLs (OR, 3.20; 95% CI, 0.78-13.16; P = 0.11). CONCLUSIONS: AcrySof and sharp-edged silicone IOLs are similarly effective in inhibition of PCO after cataract surgery. In patients implanted with the AcrySof lens, significantly less PCO developed than in those who had round-edged silicone or PMMA IOLs. The results of this meta-analysis support the theory that a major factor in preventing PCO development is a sharp-edged IOL design.

Gene-carried hepatoma targeting complex induced high gene transfection efficiency with low toxicity and significant antitumor activity.

BACKGROUND: The success of gene transfection is largely dependent on the development of a vehicle or vector that can efficiently deliver a gene to cells with minimal toxicity. METHODS: A liver cancer-targeted specific peptide (FQHPSF sequence) was successfully synthesized and linked with chitosan-linked polyethylenimine (CP) to form a new targeted gene delivery vector called CPT (CP/peptide). The structure of CPT was confirmed by (1)H nuclear magnetic resonance spectroscopy and ultraviolet spectrophotometry. The particle size of CPT/ DNA complexes was measured using laser diffraction spectrometry and the cytotoxicity of the copolymer was evaluated by methylthiazol tetrazolium method. The transfection efficiency evaluation of the CP copolymer was performed using luciferase activity assay. Cellular internalization of the CP/DNA complex was observed under confocal laser scanning microscopy. The targeting specificity of the polymer coupled to peptide was measured by competitive inhibition transfection study. The liver targeting specificity of the CPT copolymer in vivo was demonstrated by combining the copolymer with a therapeutic gene, interleukin-12, and assessed by its abilities in suppressing the growth of ascites tumor in mouse model. RESULTS: The results showed that the liver cancer-targeted specific peptide was successfully synthesized and linked with CP to form a new targeted gene delivery vector called CPT. The composition of CPT was confirmed and the vector showed low cytotoxicity and strong targeting specificity to liver tumors in vitro. The in vivo study results showed that interleukin-12 delivered by the new gene vector CPT/DNA significantly enhanced the antitumor effect on ascites tumor-bearing imprinting control region mice as compared with polyethylenimine (25 kDa), CP, and other controls, which further demonstrate the targeting specificity of the new synthesized polymer. CONCLUSION: The synthesized CPT copolymer was proven to be an effective liver cancer-targeted vector for therapeutic gene delivery, which could be a potential candidate for targeted cancer gene therapy.

Transcutaneous vaccines: novel advances in technology and delivery for overcoming the barriers.

Transcutaneous immunization represents an attractive alternative to vaccine delivery via topical administration and has received wide attention due to its easy-to-use, needle-free and noninvasive delivery. However, the development of transcutaneous vaccine was kept a challenge because of the barrier function of stratum corneum which inhibits the transport of antigen and adjuvant. Nowadays, pharmaceutical methods and novel physical devices are extensively investigated to overcome the penetration barrier of the stratum corneum for transcutaneous vaccine. In this article, these pharmaceutical methods and novel devices used for the enhancement of transcutaneous immunization were reviewed. In addition, chemokines promoted the migration of Langerhans cells and the transcutaneous adjuvants enhancing the immune responses at certain levels are also discussed for the development of novel transcutaneous vaccines.

Effective transcutaneous immunization by antigen-loaded flexible liposome in vivo.

BACKGROUND: Transcutaneous vaccines have received wide attention due to their easy-to-use, needle-free, noninvasive delivery. However, the novel barrier function of stratum corneum hinders the transport of antigen and adjuvant in transcutaneous immunization. Novel nanoscale delivery systems employing, for example, liposomes and nanoparticles, have been widely investigated to overcome the penetration barrier of stratum corneum for effective transcutaneous immunization. OBJECTIVE: The objective of this study was to prepare two types of flexible liposomes and determine their efficacies for the transcutaneous delivery of antigen and the subsequent immune response induced in vivo. METHODS: Ovalbumin (OVA) liposome-based transcutaneous vaccines were prepared using reverse-phase evaporation and film-dispersion methods. Particle sizes and antigen encapsulating efficiency were then evaluated. After application to bare mouse skin, topical sites were examined for the presence of fluorescence-labeled liposome. The efficacy of the transcutaneously delivered OVA-loaded flexible liposome in activating the immune responses was investigated by detecting serum immunoglobulin G levels. The influence of an adjuvant, imiquimod, in the transcutaneous immunization was also tested. RESULTS: Two flexible liposomes with well-encapsulated OVA were successfully prepared by film-dispersion or reverse-phase evaporation methods. The sizes of the prepared flexible liposomes ranged from 200 to 400 nm. In vivo, the fluorescence-labeled liposome was detected in hair-follicle ducts, indicating that the flexible liposome can penetrate the skin barrier through the hair follicles. Upon transcutaneous administration, the OVA-encapsulated flexible liposome elicited a strong immune response similar to that of positive control (ie, OVA solution administrated by subcutaneous injection with Al(OH)(3) as an adjuvant). Co-administration of imiquimod with the OVA-loaded liposome expressed a significant enhancement on the transcutaneous immune responses. CONCLUSION: Results of this study highlight the nanoscale formulation, flexible liposome, as a promising carrier for the transcutaneous delivery of antigen proteins. Imiquimod was shown to be an effective adjuvant as a transcutaneous immunization enhancer with the potential for transcutaneous vaccine development.