Clinical efficacy of intradermal type I collagen injections in treating skin photoaging in patients from high-altitude areas.

BACKGROUND: Photoaging, a result of chronic sun exposure, leads to skin damage and pigmentation changes. Traditional treatments may have limitations in high-altitude areas like Yunnan Province. Intradermal Col Ι injections stimulate collagen production, potentially improving skin quality. This study aims to assess the efficacy and safety of this treatment for photoaging. AIM: To evaluate the efficacy and safety of intradermal type Ι collagen (Col Ι) injection for treating photoaging. METHODS: This prospective, self-controlled study investigated the impact of intradermal injections of Col Ι on skin photodamage in 20 patients from the Yunnan Province. Total six treatment sessions were conducted every 4 wk ± 3 d. Before and after each treatment, facial skin characteristics were quantified using a VISIA skin detector. Skin thickness data were assessed using the ultrasound probes of the Dermalab skin detector. The Face-Q scale was used for subjective evaluation of the treatment effect by the patients. RESULTS: The skin thickness of the right cheek consistently increased after each treatment session compared with baseline. The skin thickness of the left cheek significantly increased after the third through sixth treatment sessions compared with baseline. The skin thickness of the right zygomatic region increased after the second to sixth treatment sessions, whereas that of the left zygomatic region showed a significant increase after the fourth through sixth treatment sessions. The skin thickness of both temporal regions significantly increased after the fifth and sixth treatment sessions compared with baseline (P < 0.05). These findings were also supported by skin ultrasound images. The feature count for the red areas and wrinkle feature count decreased following the treatment (P < 0.05). VISIA assessments also revealed a decrease in the red areas after treatment. The Face-Q-Satisfaction with Facial Appearance Overall and Face-Q-Satisfaction with Skin scores significantly increased after each treatment session. The overall appearance of the patients improved after treatment. CONCLUSION: Intradermal Col Ι injection improves photoaging, with higher patient satisfaction and fewer adverse reactions, and could be an effective treatment method for populations residing in high-altitude areas.

Application experience and research progress of different emerging technologies in plastic surgery.

In the diagnosis and treatment of plastic surgery, there are structural processing problems, such as positioning, moving, and reconstructing complex three-dimensional structures. Doctors operate according to their own experience, and the inability to accurately locate these structures is an important problem in plastic surgery. Emerging digital technologies such as virtual reality, augmented reality, and three-dimensional printing are widely used in the medical field, particularly in plastic surgery. This article reviews the development of these three technical concepts, introduces the technical elements and specific applications required in plastic surgery, summarizes the application status of the three technologies in plastic surgery, and summarizes prospects for future development.

Repair of Bone Defects With Endothelial Progenitor Cells and Bone Marrow-Derived Mesenchymal Stem Cells With Tissue-Engineered Bone in Rabbits.

PURPOSE: This study aimed to investigate the repair of bone defects in rabbits with tissue-engineered bones using cocultured endothelial progenitor cells (EPCs) and bone marrow mesenchymal stem cells (BMSCs) as seeding cells. METHODS: Endothelial progenitor cells and BMSCs were isolated and purified from the peripheral blood and bone marrow, respectively, of New Zealand rabbits. The third passage of BMSCs was cultured alone or with EPCs. Cells were characterized using specific markers and then seeded on partially deproteinized biologic bones from pigs as a scaffold. The engineered bones were used to repair bone defects in rabbits. Hematoxylin and eosin and Masson staining were performed to examine vascularization and osteogenesis in the engineered bone. RESULTS: The cocultured EPCs and BMSCs grew well on the surface of the scaffold. Compared with monocultured BMSCs, cocultured EPCs and BMSCs promoted the formation of blood vessels and bone on the scaffold, in addition to accelerating the repair of bone defects. The collagen content was significantly increased in the scaffold with cocultured EPCs and BMSCs, compared with the scaffold seeded with mono-cultured BMSCs. CONCLUSIONS: Tissue-engineered bones seeded with cocultured EPCs and BMSCs may be used effectively for the repair of bone defects.

Preparation of uniform-sized agarose beads by microporous membrane emulsification technique.

Uniform-sized agarose beads were prepared by membrane emulsification technique in this study. Agarose was dissolved in boiling water (containing 0.9% sodium chloride) and used as water phase. A mixture of liquid paraffin and petroleum ether containing 4 wt% of hexaglycerin penta ester (PO-500) emulsifier was used as oil phase. At 55 degrees C, the water phase permeated through uniform pores of microporous membrane into the oil phase by a pressure of nitrogen gas to form uniform W/O emulsion. Then the emulsion was cooled down to room temperature under gentle agitation to form gel beads. The effect of oil phase, emulsifier, especially temperature on the uniformity of the beads were investigated and interpreted from interfacial tension between water phase and oil phase. Under optimized condition, the coefficient variation (C.V.) showing the size distribution of the beads was under 15%. This was the first report to prepare uniform agarose beads by membrane emulsification, and to investigate the effect of temperature on the size distribution of the droplets and beads. The beads with different size can be prepared by using membranes with different pore size, and the result showed that there was a linear relationship between the average diameter of beads and pore size of the membranes; beads with diameter from 15 to 60 microm were able to obtain in this study.

Preparation and characterization of uniform-sized chitosan microspheres containing insulin by membrane emulsification and a two-step solidification process.

Chitosan microsphere has important application in controlled release of protein and peptide drug, because it shows excellent mucoadhesive and permeation enhancing effect across the biological surfaces. In the conventional preparation methods of chitosan microsphere, the W/O emulsion was usually prepared by mechanical stirring method, and then the droplets were solidified by glutaraldehyde. There existed limitation and shortage such as broad size distribution, de-activity of bio-drug and difficulty in drug release because protein and peptide drug have the same amino group as chitosan. In this study, we established a method to prepare uniform-sized microsphere, and solve above problems by combining a special membrane emulsification technique and a step-wise crosslinking method. That is, the chitosan/acetic acid aqueous solution was pressed through the uniform pores of a porous glass membrane into a paraffin/petroleum ether mixture containing PO-500 emulsifier, to form a W/O emulsion with uniform droplet size. Then, the uniform droplets were solidified by a two-step crosslinking method. At the first step, tripolyphosphate (TPP) solution was dropped gradually in the emulsion, TPP diffused into the droplet to crosslink chitosan by an ionic linkage, generating a microgel. At the second step, an adequate amount of glutaraldehyde was added. The solidification conditions of the two-step process were optimized by investigating the effects of solidification conditions on morphology of microspheres, encapsulation efficiency (EE), drug activity and release profile in vitro. The suitable preparative conditions were determined as follows: pH value of aqueous phase and TPP solution was 3.5-4.0, the molar ratio of amino group of chitosan to aldehyde group of glutaraldehyde was 1:1 and the crosslinking time of glutaraldehyde was 60 min.