Current surgical practices of robotic-assisted tissue repair and reconstruction.

This paper systematically reviewed and analyzed the recent publications of robotic-assisted surgeries in the field of tissue repair and reconstruction. Surgical robots can elevate skin flap more accurately and shorten the time of tissue harvest. In addition, robotic-assisted surgery has the advantage of minimal tissue trauma and thus forms minimal scar. The utilization of surgical robots reduces the occurrence of complications after oral radical tumor resection while achieving cosmetic sutures. Robotic-assisted radical mastectomy could radically remove invasive breast cancer lesions and achieve breast reconstruction in the first stage through the small incisions in the operation areas. Surgical robots enable precise microvascular anastomosis and reduce tissue edema in the surgical field. Robotic-assisted technology can help appropriately locate the target tissues at different angles during sinus and skull base surgeries and accurately place tissues during urethroplasty. The robotic-assisted technology provides a new platform for surgical innovation in the field of tissue repair and reconstruction. However, the uncertainty in the survival rate after tumor radical surgery, the increase of operating time, and the high costs are barriers for its clinical application in tissue repair and reconstructive surgery. Nevertheless, robotic-assisted technology has already demonstrated an impact on the field of tissue repair and reconstruction in a meaningful way.

An alternative model of vascularized bone marrow transplant: partial femur transplantation.

The vascularized whole femur transplantation model is one of the commonly used vascularized bone marrow transplant models. It involves technical complexity and morbidities. To optimize this model, we took 2/3 femur as the carrier of bone marrow cells, and developed a vascularized partial femur model. Four experimental groups were carried out, namely, the syngeneic partial femur transplantation, allogeneic partial femur transplantation with or without cyclosporine A, and allogeneic whole femur transplantation with cyclosporine A. The results showed that the partial femur model was technically simpler and shortened the operative and ischemia time compared to the whole femur model. Gross and histologic appearance confirmed the viability of femur, and its bone marrow inside the bone could also maintain normal morphologically at 60-day posttransplant. Besides, donor multilineage chimerism could be continuously detected in immunosuppressed allogeneic partial femur recipients at 1-, 2-, 3-, 4-, and 8-week posttransplant, and it showed no significant differences when compared with whole femur transplantation. Meanwhile, long-term engraftment of donor-origin cells was also confirmed in recipients' bone marrow, lymph nodes, and spleen, but not in thymus. Therefore, the vascularized partial femur can serve as a continuous resource of bone morrow cells and may provide a useful tool for the study of immune tolerance in vascularized composite allotransplantation.

Development of novel murine mammary imaging windows to examine wound healing effects on leukocyte trafficking in mammary tumors with intravital imaging.

We developed mammary imaging windows (MIWs) to evaluate leukocyte infiltration and cancer cell dissemination in mouse mammary tumors imaged by confocal microscopy. Previous techniques relied on surgical resection of a skin flap to image the tumor microenvironment restricting imaging time to a few hours. Utilization of mammary imaging windows offers extension of intravital imaging of the tumor microenvironment. We have characterized strengths and identified some previously undescribed potential weaknesses of MIW techniques. Through iterative enhancements of a transdermal portal we defined conditions for improved quality and extended confocal imaging time for imaging key cell-cell interactions in the tumor microenvironment.

Pre-fabricated lined axial flaps for reconstruction of extensive post-burn facial and forehead full-thickness composite defects.

From January 1996 to February 1998, three patients who suffered extensive post-burn facial and forehead composite defects were treated successfully in our Burn Unit. The delto-pectoral flap and reverse radial forearm flap were pre-fabricated with lining of free split skin grafted onto the underside of the flap. The pre-fabricated flaps were sutured in situ for 2 approximately 3 weeks. The pre-fabricated lined axial flaps were then transferred for the reconstruction of facial and forehead composite defects. The flap had good blood supply and the wounds healed by first intention. The three cases presented all achieved satisfactory functional and aesthetic results. The results show that pre-fabricated lined axial flaps for the reconstruction of extensive facial and forehead composite defects are safe, effective and relatively easy for clinical application.

CXCR4 drives the metastatic phenotype in breast cancer through induction of CXCR2 and activation of MEK and PI3K pathways.

Aberrant expression of CXCR4 in human breast cancer correlates with metastasis to tissues secreting CXCL12. To understand the mechanism by which CXCR4 mediates breast cancer metastasis, MCF-7 breast carcinoma cells were transduced to express wild-type CXCR4 (CXCR4WT) or constitutively active CXCR4 (CXCR4ΔCTD) and analyzed in two-dimensional (2D) cultures, three-dimensional reconstituted basement membrane (3D rBM) cultures, and mice using intravital imaging. Two-dimensional cultures of MCF-7 CXCR4ΔCTD cells, but not CXCR4WT, exhibited an epithelial-to-mesenchymal transition (EMT) characterized by up-regulation of zinc finger E box-binding homeobox 1, loss of E-cadherin, up-regulation of cadherin 11, p120 isoform switching, activation of extracellular signal-regulated kinase 1/2, and matrix metalloproteinase-2. In contrast to the 2D environment, MCF-7 CXCR4WT cells cultured in 3D rBM exhibited an EMT phenotype, accompanied by expression of CXCR2, CXCR7, CXCL1, CXCL8, CCL2, interleukin-6, and granulocyte-macrophage colony stimulating factor. Dual inhibition of CXCR2 with CXCR4, or inhibition of either receptor with inhibitors of mitogen-activated protein kinase 1 or phosphatidylinositol 3-kinase, reversed the aggressive phenotype of MCF-7 CXCR4-expressing or MDA-MB-231 cells in 3D rBM. Intravital imaging of CXCR4-expressing MCF-7 cells revealed that tumor cells migrate toward blood vessels and metastasize to lymph nodes. Thus CXCR4 can drive EMT along with an up-regulation of chemokine receptors and cytokines important in cell migration, lymphatic invasion, and tumor metastasis.

[Effects of myrrh extract on proliferation and collagen mRNA expression of human fibroblasts in vitro].

OBJECTIVE: To observe the effects of myrrh extract on biological characteristics of human dermal fibroblasts (Fb), and to explore its possible mechanisms in promoting wound healing. METHODS: Normal Fb was isolated from human foreskin tissue and cultured in vitro. The third to fifth passages of Fb were used in the experiment. (1) Fb were planted onto 96-well plate and divided into control group, and 1 × 10(-4), 1 × 10(-3), 1 × 10(-2), 1 × 10(-1), 1, 10, 1 × 10(2) g/L myrrh water extract groups and myrrh ethanol extract groups according to the random number table. Fb in control group were cultured with DMEM medium containing 0.25% calf serum (briefly called low-concentration serum medium), and those in various concentrations of myrrh water extract and myrrh ethanol extract groups respectively with low-concentration serum medium containing corresponding concentration of 2 kinds of myrrh extract. After being cultured for 48 h, cell morphology was observed with inverted-phase contrast microscope, and Fb proliferation activity (denoted as absorbance value) was determined with MTT method. (2) Fb were respectively planted into flasks and dishes and divided into two groups according to the random number table. Fb in control group were cultured with low-concentration serum medium, and that in 1 g/L myrrh water extract group with low-concentration serum medium containing 1 g/L myrrh water extract. After being cultured for 72 h, Fb cell cycle and the type I and III collagen mRNA expression were respectively determined by flow cytometry and real-time fluorescent quantitative PCR. Data were processed with LSD-t test. RESULTS: (1) Fb in all groups grew in long-spindle shape, but the cell fusion was much obvious in 1 g/L myrrh water extract group than in control group. Fb absorbance value in 1 × 10(-3), 1 × 10(-2), 1 × 10(-1), 1, 10 g/L myrrh water extract groups was respectively 0.378 ± 0.032, 0.402 ± 0.007, 0.390 ± 0.038, 0.453 ± 0.036, 0.390 ± 0.037, all higher than that in control group (0.332 ± 0.044, with t value respectively 2.24, 2.93, 2.69, 5.73, 2.71, P values all below 0.05). Compared with that in control group, Fb absorbance value in 1 × 10(-4) g/L myrrh water extract group was not statistically different (0.312 ± 0.048, t = 2.84, P > 0.05), while that in 1 × 10(2) g/L myrrh water extract group was significantly lower (0.154 ± 0.009, t = 7.17, P < 0.05). Fb absorbance values in 1 × 10(-3), 1 × 10(-1), 1, 10, 1 × 10(2) g/L myrrh ethanol extract groups were significantly lower than that in control group (with t values from 2.30 to 24.79, P values all below 0.05). (2) Compared with those in control group [(82.2 ± 7.9)% and (13.3 ± 2.3)%, (4.5 ± 0.8)%], the percentage of cells in G0/G1 phase in 1 g/L myrrh water extract group was obviously decreased [(74.3 ± 6.3)%, t = 6.77, P < 0.05], while those in S and G2/M phases increased [(16.6 ± 3.4)%, (9.1 ± 1.6)%, with t value respectively 7.53, 6.34, P values below 0.05]. Compared with those in control group (1.00 ± 0.05, 1.00 ± 0.06), the mRNA level of collagen III in 1 g/L myrrh water extract group was significantly up-regulated (1.38 ± 0.12, t = 3.81, P < 0.01), while that of collagen I was not statistically different (0.89 ± 0.08, t = 1.17, P > 0.05). CONCLUSIONS: Myrrh water extract can notably promote the proliferation of Fb, accelerate the cell cycle of Fb, and up-regulate the mRNA expression of type III collagen in Fb, which may be related to its mechanisms in promoting wound healing.

Reduced expression of microtubule-associated protein 1 light chain 3 in hypertrophic scars.

Autophagy is a tightly regulated physiological process essential for cellular maintenance, differentiation, development, and homeostasis. Aberration of this process associates with the pathogeneses of several diseases in mammals. Hypertrophic scar (HS) is characterized by an abundance of collagenous tissue with hypercellularity. However, the molecular mechanism in HS formation is poorly understood. We compared the autophagic capacity in HS and its normal skin (NS) counterparts and explored the molecular mechanism of autophagy during the formation of HS. Microtubule-associated protein 1 light chain 3 (LC3) proteins in HS and NS were detected by immunohistochemistry, Western blot and quantitative real-time PCR (qPCR). The data showed that LC3 positive staining in HS was less intensive relative to NS group (p < 0.05). Three forms of LC3, with molecular weights of about 19 kDa (proLC3), 18 kDa (LC3-I) and 16 kDa (LC3-II), respectively, expressed in NS by Western blot. In contrast, only proLC3 expressed while both LC3-I and LC3-II were significantly downregulated in HS. The protein level of beclin 1 in HS was significantly lower compared with NS (p < 0.05). LC3 and beclin 1 mRNA levels in HS were significantly lower than that in NS (p < 0.05). These results suggest that the generation of LC3-I and LC3-II are interrupted in HS, and that the resultant decrease of autophagic capacity may associate with the pathogenesis of HS.