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Background Conventional blepharoptosis repair methods distort the normal anatomy of levator aponeurosis and often cause a visible depressed scar in the upper eyelid. Methods The levator aponeurosis was dissected as a flap from the pretarsal tissue in mono-eyelid Asian patients who had mild to moderate congenital blepharoptosis. The flap base was advanced and repositioned on the tarsus. The margin of the distal flap was interposed and fused with orbicularis oculi muscles. Postoperative evaluation included ptosis correction, symmetry, and overall cosmetic outcomes. Results A total of 162 eyes on 97 patients were corrected using our method. Follow-up time ranged from 8 to 24 months (mean 12.4). In mild ptosis eyelids, out of 58 eyelids, 36.2% (21 eyelids), 56.9% (33), and 6.9% (4) required adequate correction, normal correction, and undercorrection, respectively, whereas in moderate ptosis, the results were 34.6% (36 eyelids), 53.9% (56), and 11.5% (12), respectively. For symmetry, 58.8% (57 cases), 32.0% (31), and 9.2% (9) resulted in good, fair, and poor outcomes, respectively. For cosmetic outcomes, 82.8% (48 eyelids), 15.5% (9), and 1.7% (1) of mild ptosis cases achieved good, moderate, and poor results in mild ptosis cases, whereas the results were 77.9% (81 eyes), 20.2% (21), and 1.9% (2), respectively, in moderate ptosis cases. The only complication among all cases was postoperative swelling. Conclusions We presented a new blepharoplasty for ptosis repair that allows both satisfactory ptosis correction and cosmetic outcomes in mild to moderate congenital blepharoptosis.

Alkali-activated materials have received considerable attention in regarding their use as environmentally sustainable alternatives to Portland cement. However, the brittleness and shrinkage cracking of these materials have hindered their wider application. An effective solution to these problems is adding fibre to the concrete. This study investigated the mechanical properties of basalt and PP fibre-reinforced alkali-activated slag (AAS) concrete. A total of 11 mixture groups with different fibre dosages and lengths were created, and 132 samples were subjected to cube compressive, prism compressive, splitting tensile, and flexural strength tests. The influence of the fibre dosage and length on the mechanical properties was determined. Owing to the different strength calculation formulas and large shrinkage of the AAS material, significant differences are observed when the tensile strength of AAS concrete is characterized analysed through splitting tensile and flexural strength tests. For the same fibre length and dosage, PP fibre did not improve the strength of AAS concrete as effectively as basalt fibre did. According to the experimental results, a mathematical method was proposed to determine an optimal solution to the bivariate problem.

This paper presents a study on the shear performance of two different high-performance chopped fibers (basalt fiber and polyacrylonitrile fiber) employed to reinforce lightweight aggregate concrete. Environmentally friendly supplementary cementitious materials, fly ash and silica fume, are used to substitute a part of cement. Around 21 UDVW specimens are designed to test shear performance. The relationships between the shear strength and the cube compressive strength, splitting strength, flexural strength, and specific strength are established. Although the addition of the fibers does not change the shear failure morphologies, but could change the development direction of the cracks. Moreover, the fibers increase both the peak shear stress and the peak shear strain, and corresponding calculation models are proposed to predict these properties using the coefficient of shear strength enhancement βs. When the fiber content reaches 1% and 1.5%, the normalized shear stress–strain compared wrapped that of plain specimen notably. With an increase in the fiber content, the peak secant shear modulus decreases slightly, whereas the initial tangent shear modulus increases. Moreover, calculation methods are established to compute the peak secant shear modulus and the initial tangent shear modulus. The calculated results of several equations in this study present excellent agreement with the test results.

The objective of the study is to examine the influence of high sustained loads and longitudinal reinforcement on the long-term deformation of concrete beams. First, the influence of high sustained loads on the creep of reinforced concrete beams was investigated using five beams with load levels (ratio of sustained load to failure load) of 0.3, 0.4, 0.5, 0.6, and 0.7. A load level of 0.3 is the service load for a comparative analysis, and load levels of higher than 0.3 are considered high loads. The influence of the longitudinal reinforcement on the creep of the reinforced concrete beams was then studied using four beams with a ratio of longitudinal reinforcement of 0.81%, 1.55%, 2.14%, and 2.72%, respectively. Furthermore, the influences of the load levels and longitudinal reinforcement on the curvature creep, creep of the concrete at the edge of the compressive zone, and the mid-span deflection creep were analysed. Moreover, a comparison between the test data and the existing calculation model of the deformation of a beam was conducted, and the existing model used to predict the long-term deflection of reinforced concrete beams with high sustained loads within a wide range of longitudinal reinforcement ratios was modified. Finally, post-creep tests of the beams were conducted and the calculated formulas of the total strain (the sum of the initial strain, creep strain, and increased strain after creep) of the concrete at the compression edge of the beams was obtained through a regression analysis.

In this study, an experimental investigation was conducted on the mechanical properties of lightweight aggregate concrete (LWAC) with different chopped fibers, including basalt fiber (BF) and polyacrylonitrile fiber (PANF). The LWAC performance was studied in regard to compressive strength, splitting tensile strength and shear strength at age of 28 days. In addition, the oven-dried density and water absorption were measured as well to confirm whether the specimens match the requirement of standard. In total, seven different mixture groups were designed and approximately 104 LWAC samples were tested. The test results showed that the oven-dried densities of the LWAC mixtures were in range of 1.819&ndash, 1.844 t/m3 which satisfied the definition of LWAC by Chinese Standard. Additionally, water absorption decreased with the increasing of fiber content. The development tendency of the specific strength of LWAC was the same as that of the cube compressive strength. The addition of fibers had a significant effect on reducing water absorption. Adding BF and PANF into concrete had a relatively slight impact on the compressive strength but had an obvious effect on splitting tensile strength, flexural strength and shear strength enhancement, respectively. In that regard, a 1.5% fiber volume fraction of BF and PANF showed the maximum increase in strength. The use of BF and PANF could change the failure morphologies of splitting tensile and flexural destruction but almost had slight impact on the shear failure morphology. The strength enhancement parameter &beta, was proposed to quantify the improvement effect of fibers on cube compressive strength, splitting tensile strength, flexural strength and shear strength, respectively. And the calculation results showed good agreement with test value.

The hair follicle serves as a melanocyte reservoir for both hair and skin pigmentation. Melanocyte stem cells (MelSCs) and melanocyte progenitors reside in the bulge/sub-bulge region of the lower permanent portion of the hair follicle and play a vital role for repigmentation in vitiligo. It would be beneficial to isolate MelSCs in order to further study their function in pigmentary disorders; however, due to the lack of specific molecular surface markers, this has not yet been successfully accomplished in human hair follicles (HuHF). One potential method for MelSCs isolation is the “side population” technique, which is frequently used to isolate hematopoietic and tumor stem cells. In the present study, we decided to isolate HuHF MelSCs using “side population” to investigate their melanotic function. By analyzing mRNA expression of TYR, SOX10, and MITF, melanosome structure, and immunofluorescence with melanocyte-specific markers, we revealed that the SP-fraction contained MelSCs with an admixture of differentiated melanocytes. Furthermore, our in vivo studies indicated that differentiated SP-fraction cells, when fabricated into a cell-chitosan/gelatin composite, could transiently repopulate immunologically compromised mice skin to regain pigmentation. In summary, the SP technique is capable of isolating HuHF MelSCs that can potentially be used to repopulate skin for pigmentation.

Adipose-derived stem cells (ADSCs) have an immunomodulatory role in vascularized composite tissue allo-transplantation (VCA). However, the specific effects of ADSCs on lymphocytes remain to be fully elucidated. The present study examined the changes in T cells co-cultured with ADSCs in terms of the proliferation by Cell Counting Kit-8 assay, cell cycle profile and apoptosis by flow cytom-etry, inflammatory cytokine production by polymerase chain reaction and ELISA, in addition to the expression of survival proteins by western blotting. The ADSCs reduced the viability of Jurkat T cells and downregulated the transcription of tumor necrosis factor-α and transforming growth factor-β1. Co-culture with ADSCs also induced apoptosis and increased the levels of phosphorylated c-Jun N-terminal kinase in the T cells. Taken together, these findings confirmed that ADSCs modulate the host immune response by suppressing T cells.

Temporary ectopic implantation has been performed in clinical practice to salvage devascularized amputated tissues for delayed replantation purpose. In this study, we established a series of segmental forelimb ectopic implantation models in rats, including forelimb, forearm, forepaw, digit, and double forelimbs, to mimic the clinical context. Time of amputated limbs harvesting in donors and ectopic implantation process in recipients were recorded. Survival time and mortalities of recipients were also recorded. Sixty days after ectopic implantation, a full-field laser perfusion imager (FLPI) was used to detect the blood flow of amputated limbs and micro-CT imaging was used to examine bone morphological changes. Histological sections of amputated limbs were stained with hematoxylin and eosin to evaluate pathological changes. Implanted amputated limbs in all models achieved long term survival and there were no obvious morphological and histological changes were found according to results of micro-CT and histology study. Thus, a series of rat segmental forelimb temporary ectopic implantation models have been well established. To our knowledge, this is the first rodent animal model related to forelimb temporary ectopic implantation. These models might facilitate further research related to salvage, reconstruction and better aesthetic and functional outcome of upper extremity/digit in temporary ectopic implantation scenario.

Alkali-activated materials have attracted increasing interest owing to their excellent properties and environmental protection. However, there have been few studies on their creep properties. The aim of this article is to investigate the effect of the stress&ndash, strength ratio on the creep property of sodium silicate&ndash, based alkali-activated slag (AAS) concrete. For this reason, five groups of AAS concrete with different stress&ndash, strength ratios (0.15, 0.3, 0.45, 0.6, and 0.75) were tested. The results indicate that the creep of AAS concrete has a convergent nonlinear stage and a non-convergent stage but not an obvious linear stage. The AAS concrete basically has a consistent creep coefficient and diverse specific creep under a stress&ndash, strength ratio of 0.15&ndash, 0.6. The elasticity modulus of AAS is much smaller than that of ordinary Portland cement (OPC) concrete, which is the reason for the greater creep compared to that in OPC concrete, and the inaccuracy of the model prediction. By applying the actual elastic modulus, the models can predict the specific creep and stress-dependent strain of AAS concrete with a 0.3 stress&ndash, strength ratio, except for the B3 model. The secant modulus of AAS concrete decreases linearly with an increase in the stress&ndash, strength ratio. Finally, we propose an improved creep model for AAS concrete with a wide stress&ndash, strength ratio based on the GL2000 model.

Several animal models of skin flap construction were reported using biomaterials in a way similar to prefabrication. However, there are few animal model using biomaterials similar to prelamination, another main way of clinical skin flap construction that has been proved to be reliable. Can biomaterials be added in skin flap prelamination to reduce the use of autogenous tissues? Beside individual clinical attempts, animal model is needed for randomized controlled trial to objectively evaluate the feasibility and further investigation. Combining human Acellular Dermal Matrix (hADM) and autologous skin graft, we prelaminated flaps based on inguinal fascia. One, two, three and four weeks later, hADM exhibited a sound revascularization and host cell infiltration. Prelaminated skin flaps were then raised and microsurgically transplanted back to groin region. Except for flaps after one week of prelamination, flaps from other subgroups successfully reconstructed defects. After six to sixteen weeks of transplantation, hADM was proved to being able to maintain its original structure, having a wealth of host tissue cells and achieving full revascularization.To our knowledge, this is the first animal model of prelaminating skin flap with biomaterials. Success of this animal model indicates that novel flap prelamination with biomaterials is feasible.

Epicanthal fold, which is unique to Asian population, forms a web across and covering the medial canthus. It often impairs the beauty of the eyelids and the outcome of double-eyelid blepharoplasty that is popular in Asians. Although many surgical procedures have been reported, most of them were only description of a single technique. Comparison among techniques will help form universally accepted algorithm or consensus in epicanthus treatment. We want to present our experience of three kinds of epicanthoplasties: horizontal incision method, Z-plasty and V-W plasty and a detailed comparison among these surgical techniques. From 2005 to 2011, the authors had performed epicanthoplasties in 252 cases, in which 220 cases simultaneously underwent a double-eyelid surgery. The choice of technique was based on presurgical evaluation of severity of epicanthal fold. Horizontal incision method was used for majority of mild epicanthal fold. Z-plasty mainly applied to moderate cases and V-W plasty was chosen for severe ones. In addition to skin rearrangement in medial canthic region, underlying orbicularis oculi muscle and thick subcutaneous tissue also needed treatment for effective release. The degree of postoperative scarring and epicanthal fold correction were reviewed. All these three methods produced satisfactory long-term results with alleviation of the skinfold and formation of vivid upper eyelid crease. No complete recurrence was observed. Horizontal incision method left an inconspicuous scar and V-W plasty might cause a relatively obvious scar. Persistent hypertrophic scars were observed in 12 patients and gradually faded after injection of diprospan. In conclusion, preoperative evaluation of skinfold severity, making a rational choice and careful implementation of surgical technique available are important in effective correction of epicanthal fold.

Introduction Severe cervical contracture after burns causes obvious impairment of neck movement and the aesthetic silhouette. Although various surgical techniques for treatment have been described, there is not a definitive strategy to guide treatment. Over the past 6 years, we have been utilizing a region-oriented and staged treatment strategy to guide reconstruction of severe cervical contracture. Satisfactory results have been achieved with this strategy. Methods The first stage of treatment focuses on the anterior cervical region and submental region. Procedures include cicatrix resection, contracture release, division and elevation of the platysma to form two platysma flaps, and skin grafting. Three to six months later, the second stage treatment is performed, which localize to the mental region. This includes scar resection, correction of the lower lip eversion, and reconstruction with free (para)scapular skin flap. Three subtypes of cervicomental angle that we proposed were measured as quantitative tool for evaluation of the reconstruction. Results 24 patients who completed the treatment were reviewed. By the 3rd postoperative month, their CM angles changed significantly: the soft tissue CM angle was reduced from 135.0° ± 17.3° to 111.1° ± 11.3°, the osseous CM angle increased from 67.1° ± 9.0° to 90.5° ± 11.6° and the dynamic CM angle increased from 21.9° ± 8.7° to 67.4° ± 13.1°. 22 in 24 (91.7%) of these patients gained notable improvement of cervical motion and aesthetic contour. Conclusions Our results suggest that the region-oriented and staged treatment strategy can achieve satisfactory functional and aesthetic results, combining usage of both skin graft and skin flap while minimizing the donor site morbidity.