Buttock Augmentation with Fat Grafting.

Refined buttock augmentation with fat grafting in Chinese women during the past decade is introduced. The ideal buttock contouring outcome and figure silhouette come from the proper individualized plan and meticulous maneuvers through fat grafting to the buttocks combined with liposuction procedures on the surrounding areas of the buttocks as well as on the other body parts. The fat grafts are collected, filtered, and condensed by gravitation in a sterilized canister during liposuction. It is recommended that fat grafts were only transplanted into the subcutaneous layers and with no injection into the musculatures of the buttocks. High patients' satisfaction was obtained with no major complications and fewer minor complications.

Midface Rejuvenation With Autologous Fat Grafting.

BACKGROUND: Midface rejuvenation is important to restore a youthful and appealing appearance. However, there are several problems existed in the treatment of fat grafting, including low fat retention and undesired aesthetic outcomes. OBJECTIVE: To objectively evaluate the efficacy of midface fat grafting, and analyze the problems encountered in this process to increase patient satisfaction. METHODS: Thirty-two patients who underwent autologous fat grafting for midface augmentation were included. Facial analysis was performed based on preoperative and postoperative photographs. Satisfaction outcome was assessed by the patient, the surgeon, and a layperson postoperatively. RESULTS: After treatment, 87.5% of the patients were assessed as satisfactory and mostly satisfactory based on facial proportion and complications. The postoperative medial cheek projection was 1.92±0.26 times the height of the preoperative one ( P <0.01). A smooth lid-cheek junction, a single convex, and ameliorated nasolabial groove were obtained. The dark coloration and wrinkles in lower eyelid were improved. The most common complication was overcorrection, which could be resolved with further treatments. CONCLUSIONS: Autologous fat grafting remains an optimal option for midface rejuvenation with satisfactory results. Most of the complications are preventable and optimal outcomes can be obtained through correct comprehension of aesthetic features and proper operations.

Experimental Study on the Biological Outcome of Auricular Cartilage and Costal Cartilage at Different Time Periods After Autologous Cartilage Rhinoplasty.

Since autologous cartilage is a good transplant material, it is widely used in various fields of clinical medicine. In this study, we collected clinical specimens obtained at different numbers of years after transplantation and used histologic staining to explore the post-transplantation changes in auricular cartilage and costal cartilage. A retrospective analysis was performed on patients who underwent primary autologous cartilage rhinoplasty and secondary rhinoplasty from 2017 to 2021, and the remaining autologous cartilage tissue after surgery was used for histologic testing. As time progressed after transplantation, the density of costal chondrocytes decreased first and then increased, while the secretion of type II collagen and extracellular matrix both decreased slightly. There was a clear boundary between the cartilage tissue and the surrounding connective tissue, and there was no ingrowth of blood vessels in the cartilage. Auricular cartilage showed a decrease in the integrity of the matrix edge. Moreover, local fibrosis was visible, and vascular ingrowth was observed at the edge of the cartilage. The content of type II collagen first increased and then decreased, and the cell secretion function was lower than that of normal chondrocytes. The results of the study suggest that the histologic outcome of elastic cartilage after transplantation is significantly different from that of hyaline cartilage. Moreover, costal cartilage was more stable than auricular cartilage after transplantation.

Biological Changes of Autologous Auricular Cartilage in Rhinoplasty.

Autologous auricular cartilage is used extensively as a good graft material in rhinoplasty. In this study, clinical specimens from patients who underwent revision rhinoplasty with auricular cartilage grafts were collected to compare the changes before and after auricular cartilage transplantation with the use of histologic, immunohistochemical, and quantitative assays. Patients who underwent revision rhinoplasty from 2018 to 2022 were analyzed. Fresh auricular cartilage left after surgery and auricular cartilage graft tissue were examined and compared. Compared with fresh auricular cartilage, local fibrosis was seen in the transplanted auricular cartilage with a slight decrease in elastic fibers, type II collagen, and extracellular matrix secretion. Quantitative assays showed a decrease in glycosaminoglycan, DNA, and total collagen content in the transplanted auricular cartilage tissue. The results of the study suggest that the histologic characteristics, cell functionality, and biochemical composition of the grafted cartilage changed to a certain extent after autologous auricular cartilage graft rhinoplasty. These results provide insights into the selection of graft/filler materials for rhinoplasty and what changes to expect.

Histopathological and Immunohistochemical Features of Small to Big Satellite Nevus Uncover the Nevogenesis of Large/Giant Congenital Melanocytic Nevus.

The nevogenesis of large/giant congenital melanocytic nevus (lgCMN) is a complex biological process including several integral prenatal stages. Limited by ethical concerns, the debate of whether lgCMN develops from the epidermis to the dermis or in the opposite direction remains controversial. With the present study of the accompanying satellite nevi, we tend to support that lgCMN develops from epidermis to dermis. The satellite nevi were divided into 3 groups: big (diameter >10 mm), medium (>5 mm but ≤10 mm), and small (≤5 mm). Hematoxylin and eosin and immunohistochemical staining (SOX10, Ki67, and p16) were performed to compare the nevocyte infiltration depth as well as the positively stained rates among these satellite nevi. Compared to big satellite nevi, less deeply the nevocytes infiltrated the dermis, as well as more cells expressed SOX10 and Ki67 in the epidermis and fewer cells expressed p16 in the dermis of small satellite nevi. Additionally, two specimens were obtained from each of 4 patients who underwent serial resections of lgCMN at an average interval of 1.75 years to examine the histopathological changes. In the present study, satellite nevi of different sizes represent different stages of lgCMN from early to late, deepening our comprehension of the sequential stages of lgCMN nevogenesis. Initially, abnormal nevocytes seeded, proliferated, and spread along the epidermis. At rete ridges that protrude from the papillary dermis within the epidermis, some nevocytes formed nests and gradually penetrated into the dermis. Eventually, the nevocytes infiltrated the dermis and entered a homeostatic state. This study provides new evidence supporting the theory of epidermal-to-dermal nevogenesis in lgCMN.

Long-term volume retention after fat processing with cotton gauze rolling and centrifugation: A comparative study in nude mice.

BACKGROUND: Autologous fat grafting for correcting soft-tissue defects in cosmetic and reconstructive procedures has grown in popularity. Fat processing is implicated as a variable affecting quality, viability, and subsequent graft retention. This study aimed to identify a better fat processing technique for optimal outcomes. METHODS: Fresh human aspirated fat was processed with cotton gauze rolling or centrifugation and named rolled fat (RF) and centrifuged fat (CF), respectively. Processed fat grafts were analyzed in vitro to determine yield, stromal vascular fraction (SVF) content, and viability. Then, RF and CF were transplanted subcutaneously to different flanks of every nude mouse. Fat samples were weighed to evaluate the volume retention 3 months post-transplantation. Tissue structure, densities of vessels, and CD68-positive macrophages were examined by histological staining. RESULTS: The compression rate of lipoaspirate by cotton gauze rolling was 25%, which was more effective than the rate of 50% by centrifugation. The numbers of SVF cells per gram of RF and CF were (1.02 ± 0.14) ×106 and (0.65 ± 0.26)×106, respectively (P < 0.05). Long-term graft retention was significantly higher in the RF group than in the CF group. Histological analysis of all implants revealed intact adipose tissue and equivalent vascularity. The number of CD68-positive macrophages in the RF group was much less than in the CF group on day 7. CONCLUSION: The results of this animal experiment showed that, compared with centrifugation, processing with cotton gauze rolling produces more condensed fat, higher SVF content, and decreased inflammatory response, thereby improving long-term volume retention. Further explorations are required to verify the superiority of cotton gauze rolling in clinical settings.

Analysis of Factors Affecting Postoperative Drainage After Comprehensive Rhinoplasty.

This study aimed to explore and analyze the factors influencing the drainage volume after comprehensive rhinoplasty. The clinical data of 102 patients who underwent comprehensive rhinoplasty at Shanghai Ninth People's Hospital affiliated to Shanghai Jiao Tong University School of Medicine from August 2019 to August 2021 were retrospectively analyzed. The effects of age, sex, body mass index, whether an osteotomy was performed, and whether a nasal septum flap was obtained on the indwelling time of the drainage tube after the operation were analyzed by single factor analysis and multiple logistic regression analysis. Age, body mass index, whether it was a primary rhinoplasty, whether an osteotomy was performed, and whether a nasal septum flap was obtained were the influencing factors for drainage time after augmentation rhinoplasty ( P <0.05). Sex had little effect on the drainage time after comprehensive rhinoplasty ( P >0.05). Body mass index, whether an osteotomy was performed and whether a nasal septum flap was obtained were the independent influencing factors for the postoperative drainage time ( P <0.05). For patients with multiple independent influencing factors, individualized management during the perioperative period should be promoted, and reasonable treatment strategies should be formulated, so as to reduce the indwelling time of the drainage tube after the operation.

Enzymatic Preparation of Gentiooligosaccharides by a Thermophilic and Thermostable ß-Glucosidase at a High Substrate Concentration.

Gentiooligosaccharides (GnOS) are a kind of oligosaccharide formed by glucose with ß-1-6 glycosidic bonds, which has become a new type of functional oligosaccharide for its unique refreshing bitter taste and valuable probiotic effects. However, the research on the enzymatic preparation of GnOS is not thorough enough. In this study, a GH1 thermophilic ß-glucosidase from Thermotoga sp. KOL6 was used as a biocatalyst for the synthesis of GnOS. TsBgl1 exhibited excellent thermophilic and thermostable properties by possessing a melting temperature of 101.5 °C and reacting at 80-90 °C efficiently. Its half-life at 90 °C was approximately 5 h, suggesting its high heat resistance as well. TsBgl1 also showed excellent glucose tolerance with an inhibition constant (Ki) of 1720 mM and was stimulated in the presence of 0-900 mM glucose. TsBgl1 showed the highest hydrolytic activity on laminaribiose (Glc-ß-1,3-Glc), but mainly synthetized gentiobiose (Glc-ß-1,6-Glc) during transglycosylation. By optimizing the reaction conditions and substrate concentration, the highest yield of GnOS synthesized by TsBgl1 reached 144.3 g·L-1 when 1000 g·L-1 glucose was used as a substrate, which was higher than the highest yield ever reported. The thermophilic and thermostable properties of TsBgl1 were considered to be significant advantages in the industrial production of GnOS, where long periods of high-temperature reactions are required. This study was expected to provide an excellent candidate enzyme for industrial production of GnOS and also provide a reference for studying the transglycosylation of GH1 ß-glucosidases.

Eyelid Lymphatics: An Anatomical Study by Microdissection.

OBJECTIVE: To obtain further understanding of the eyelid lymphatic anatomy. METHOD: Thirty-two halves of eyelids from 16 fresh fetus cadavers were studied by microdissection using a mixture of 3% Prussian blue and chloroform to visualize the lymphatic vessels. RESULTS: Three layers of lymphatic plexuses were demonstrated in the eyelids: a superficial or preorbicularis muscle plexus; a pretarsal or postorbicular muscle plexus; and a deep or posttarsal plexus. Furthermore, communicating branches among these plexuses were also spotted. CONCLUSIONS: The study results demonstrated the topographic distribution of the eyelid lymphatic vessels and confirmed the existence of communicating branches. This discovery will be conducive to understanding the route and mechanism by which inflammation of the eyelid spreads and cancer disseminates. It also provides anatomical insights to apply during eyelid surgery with regard to the prevention of possible eyelid lymphatic injury.

Bleomycin sclerotherapy for large diffuse microcystic lymphatic malformations.

BACKGROUND: Microcystic lymphatic malformations (LMs) are congenital lesions with the diameter of the majority of cysts <1 cm. Bleomycin sclerotherapy has been shown to yield beneficial results for macrocystic LMs. This study aims to evaluate the safety and efficacy of consecutive bleomycin sclerotherapy for large diffuse microcystic LMs. METHODS: The location and size of the lesions were detected by ultrasound for the 46 patients included in this study. Bleomycin lavage was performed in larger cysts and intradermal injection for the superficial lesion. The outcome and complications were assessed for its efficacy and safety. RESULTS: The large diffuse microcystic LMs mainly located in the neck, abdominal wall and axilla/lateral chest wall. The average lesion size was 10.6 cm × 7.2 cm. The mean number of treatment sessions was 4.5 with 7.3 mg bleomycin for per session averagely. Excellent (69.6%) and moderate (23.9%) responses were obtained. There was no recurrence for the 6 patients (13%) who received a long follow-up. Obvious local swelling, slight intralesional hemorrhage and low-grade fever were the most commonly occurred complications. No lung fibrosis was identified for the patients who received more than 6 sessions. CONCLUSIONS: Local lavage combined with intradermal injection of bleomycin is effective and safe for large diffuse microcystic LMs with good therapeutic effect and low complication rates, and can be regarded as the mainstay of therapy for microcystic LMs.

Surgical reconstruction of massive scrotal lymphedema associated with hidradenitis suppurativa: a case report.

Hidradenitis suppurativa (HS) is a chronic, recurrent inflammatory cutaneous disease affecting apocrine glands. It can be associated with lymphedema of the surrounding tissues and most commonly affects scrotum. As a debilitating complication of HS, lymphedema can cause significant morbidity and further exacerbate HS condition, thus causing a vicious cycle. Surgery was reported to be the most common treatment for this complication. Here, we present a 41-year-old patient with massive scrotal lymphedema following a 2-year history of HS. To reduce the volume of the scrotal mass and improve the appearance and function of the scrotum, we modified the Charle's procedure by complete excision of the affected tissue while retaining the scrotal septum, preserving the subcutaneous lymphatic tissue flap, turnover of the perididymis, and primary closure. We found that this approach achieved satisfactory cosmetic results, maintained cutaneous sensation and restored erections. There was no adverse event following surgery. No recurrence occurred over 6-month of follow-up. We believe that this modified Charles' procedure can improve the morphology and lymphatic function of the scrotum and recommend its use whenever possible. While rare, HS associated lymphedema should alert clinician to the potential consequence of an advanced disease situation. Collaborative approach with surgery in the management of this condition should be considered at early stage.

Increased levels of YKL-40 in patients with diabetes mellitus: a systematic review and meta-analysis.

BACKGROUND: Diabetes mellitus (DM) could be classified as type 1 diabetes mellitus (T1DM), type 2 diabetes mellitus (T2DM), gestational diabetes mellitus (GDM) and others according to etiology and pathology. Diabetic nephropathy (DN) is one of the most serious complications of DM. YKL-40 is a marker of inflammation and some studies have indicated that DM was related with inflammation. The objective of our study is to perform a systematic review and meta-analysis to confirm the relationship between YKL-40 and DM as well as DN. METHODS: Pubmed, Embase, CNKI and Chinese wanfang databases were searched for eligible studies by two independent authors. Studies were included in this meta-analysis if they fulfilled the following inclusion criteria: (1) a study involving the role of YKL-40 in DM (or DN) designed as a case-control study or cohort study; (2) the data of serum YKL-40 levels were available; (3) studies were published in English or Chinese. Finally, twenty-five studies were included in this meta-analysis. RESULTS: Compared with healthy controls, DM patients had significantly higher levels of YKL-40 (DM: SMD = 1.62, 95% CI 1.08 to 2.25, P = 0.000; GDM: SMD = 2.85, 95% CI 1.01 to 4.70, P = 0.002). Additionally, DM patients with different degree of albuminuria had significantly higher levels of YKL-40 compared with healthy controls (normoalbuminuria: SMD = 1.58, 95% CI 0.59 to 2.56, P = 0.002; microalbuminuria: SMD = 2.57, 95% CI 0.92 to 4.22, P = 0.002; macroalbuminuria: SMD = 2.69, 95% CI 1.40 to 3.98, P = 0.000) and serum YKL-40 levels increased with increasing severity of albuminuria among DM patients (microalbuminuria vs normoalbuminuria: SMD = 1.49, 95% CI 0.28 to 2.71, P = 0.016; macroalbuminuria vs microalbuminuria: SMD = 0.93, 95% CI 0.34 to 1.52, P = 0.002). CONCLUSIONS: Our current meta-analysis demonstrates that serum level of YKL-40 is increased in DM and positively associated with the severe degree of albuminuria. Therefore, we suggest that YKL-40 could be considered to be detected, along with other inflammatory markers, if DM, especially DN, is suspected.

Surgical reconstruction of primary genital lymphedema-long term therapeutic efficacy.

BACKGROUND: Primary genital lymphedema is caused by congenital lymphatic dysplasia, which is often accompanied by lymphedema of the lower extremities. A lack of effective diagnostics and treatments are available in clinical practice. The purpose of this study is to present the experience of surgical treatment of genital lymphedema and follow-up magnetic resonance lymphangiography (MRL) examinations. METHODS: The clinical records of 40 patients diagnosed with primary genital lymphedema between 2010 and 2019 were retrospectively reviewed. The surgical management of all patients consisted of complete excision of the edematous subcutaneous tissue and plastic reconstruction of the penis or scrotum. This involved excision of the affected tissue while retaining the scrotal septum, preserving the subcutaneous lymphatic tissue flap, turnover of the perididymis, and primary closure. All patients were examined by MRL to assess the extent of lymphedema pre- and postoperatively. The cosmetic results, recovery of sexual function, patient satisfaction, and complications are discussed. RESULTS: A total of 40 patients underwent surgical treatment. Scrotal hematoma (2.5%) and poor wound healing (5%) were encountered postoperatively. During follow-up period, no recurrence of edema occurred. The appearance of the scrotum and penis, as well as the sexual function was improved. MRL confirmed tissue edema and lymphatic malformation in the enlarged penis and scrotum preoperatively. In follow-up MRL, new formation or reopen of lymphatic drainage can be detect in 25 (62.5%) patients. All patients showed decreased area of dermal backflow. CONCLUSIONS: Surgical treatment is necessary for genital lymphedema when swelling develops. The use of a retained scrotal septum and subcutaneous lymphatic tissue flaps can achieve improved morphology and function. MRL is a safe and accurate diagnostic imaging method for pre- and postoperative evaluation of lymphedema in patients undergoing lymphatic surgery.

Magnetic Resonance Lymphography of Lymphatic Vessels in Upper Extremity With Breast Cancer-Related Lymphedema.

BACKGROUND: Magnetic resonance lymphangiography (MRL) has been proven to be able to visualize pathological lymphatic networks and accompanying complications through subcutaneous injection of commonly used contrast agents. However, no comprehensive prior studies have previously been reported regarding MRL for the evaluation of upper extremity lymphedema in patients with breast cancer-related lymphedema (BCRL). In this study, we establish a novel MRL protocol to characterize the normal and abnormal characteristics of different clinical stages of BCRL in patients using high-spatial-resolution MRL. METHODS: Fifty females with unilateral upper extremity BCRL underwent MRL. Lymphatic vessel morphology in normal and affected limbs was compared. The appearance, distribution pattern, morphologic characteristics, and maximum transversal diameter of the lymphatic vessels, dermal backflow, and regeneration of lymphatic vessels were analyzed. RESULTS: Lymph fluid was retained in the subcutis of the affected limbs, and no edema was observed in the subfascial compartment. In stage 1, tortuous and dilated lymphatic vessels exhibited a beaded appearance, and their diameters were larger than those in the contralateral forearm (P < 0.05). In stage 2, the dilated lymphatic vessels exhibited larger diameters. "Dermal backflow" and tiny regenerated lymphatic vessels appeared. The thickened subcutaneous tissue showed a honeycomb pattern induced by soft tissue fibrosis and adipose hypertrophy. In stage 3, disordered and unrecognizable affected lymphatic vessels were observed with many small regenerated lymphatics and confluent dermal backflow; the tissue fibrosis was more serious. CONCLUSIONS: Each stage presents different characteristics, and the deformity degree of the lymphatic network is consistent with the severity of the disease. Magnetic resonance lymphangiography could provide adequate information for clinical staging in patients with BCRL.

A large-scale collection of giant congenital melanocytic nevi: Clinical and histopathological characteristics.

Giant congenital melanocytic nevi (GCMN) place a heavy psychological burden on patients due to their poor cosmetic appearance. The histopathological characteristics of GCMN have remained largely elusive. The present study investigated the histopathological characteristics of GCMN in association with their clinical appearance. A total of 98 patients diagnosed with GCMN were included in the present study and their clinical features were collected from their records. Lesion specimens were obtained and stained for histopathological analysis. Regarding the microscopic appearance of GCMN, nevi cells in the whole dermis exhibited different patterns than those in healthy tissues. Most GCMN cases featured a sub-epidermal non-involvement zone, which implies an early occurrence in embryo development. Darker nevi exhibited a higher density of infiltrated nevi cells and more pigment deposition; this appears to induce a poor skin texture. Chemical peeling and laser therapy only partly removes pigment particles and nevi cells in the upper portion of the dermis. The clinical features of GCMN are associated with the histopathological characteristics, and non-surgical therapy cannot remove the nevus cells in the deep dermis.

Emulsified Fat Grafting Accelerates Tissue Expansion: An Experimental Study in a Rat Model.

INTRODUCTION: Tissue expansion has been applied in tissue repair and reconstruction of large soft tissue defects. Stromal vascular fraction (SVF) transplantation is a promising treatment in raising expansion efficiency. However, the clinical utilization of SVF is limited because of its conventional collagenase-based production. The aim of this study was to evaluate the effect of emulsified fat (EF), SVF obtained by using mechanical method, on accelerating tissue expansion. MATERIALS AND METHODS: The microstructure of EF fragments and the proportion of mesenchymal stem cells (MSCs; CD45-/CD34+) in EF were detected. Wistar rats were divided into the following 3 groups randomly: the 1-mL EF group, the 0.5-mL EF group, and the control group. The tissue expansion was carried out twice a week to maintain the capsule pressure at 60 mm Hg. After 4 weeks, inflation volume and histological changes, which includes collagen content, cell proliferation, and capillary density, were observed to evaluate the effect of EF on tissue expansion. RESULTS: Mechanical emulsification effectively destroyed the mature adipocytes in adipose tissue. The proportion of MSCs population in the EF fragments was 12.40 ± 0.86%. After expansion, the inflation volume and the levels of collagen deposition, cell proliferation, and capillary density of the expanded tissue in the 1-mL EF group were significantly higher than that in the 0.5-mL EF group and the control group (P < 0.05). However, all these regenerative indicators in the 0.5-mL EF group showed no statistical difference from the control group (P > 0.05). The thickness of epidermal and dermal layers showed no significant difference among the 3 groups (P > 0.05). CONCLUSIONS: Our findings suggested that EF grafting can be used as a new alternative to increase tissue expansion efficiency.

Therapeutic effects of targeting RAS-ERK signaling in giant congenital melanocytic nevi.

Most giant congenital melanocytic nevi (GCMN) exhibit an activating mutation in NRAS. Constitutive activation of the RAS-ERK signaling pathway induces proliferation in nevus cells and plays a pivotal role in melanoma development. In this study, we studied the efficacy of RAS-ERK pathway targeted therapy in GCMN. We isolated nevus cells from GCMN (GNCs) and compared the morphology of GNCs with normal melanocytes and the A375 melanoma cell line. Proliferation curves of GNCs and A375 cells were determined using Cell Counting Kit-8 assays. Cell cycle distribution was measured using flow cytometry. The RAS-ERK pathway inhibitors Vemurafenib and Trametinib, which are used in melanoma therapy, were applied. After inhibitor treatment, GNCs were analyzed for apoptosis and the protein expression of ERK, p-ERK, P38, p-P38 and P53. We found that compared with A375 cells, the cultured GNCs exhibited a higher G1 phase population and a lower proliferation rate. Both Vemurafenib and Trametinib treatment induced GNCs apoptosis in a dose-dependent manner, with Vemurafenib having a stronger effect. With inhibitor treatment, ERK activation was greatly suppressed, while the expression of p-P38 exhibited no obvious change. Vemurafenib treatment also increased the level of P53 protein in GNCs. These findings suggested that Vemurafenib treatment may be a potential therapeutic strategy for treatment of GCMN via targeting of the RAS-ERK pathway.

Characterization and analysis of CCR and CAD gene families at the whole-genome level for lignin synthesis of stone cells in pear (Pyrus bretschneideri) fruit.

The content of stone cells has significant effects on the flavour and quality of pear fruit. Previous research suggested that lignin deposition is closely related to stone cell formation. In the lignin biosynthetic pathway, cinnamoyl-CoA reductase (CCR) and cinnamyl alcohol dehydrogenase (CAD), dehydrogenase/reductase family members, catalyse the last two steps in monolignol synthesis. However, there is little knowledge of the characteristics of the CCR and CAD families in pear and their involvement in lignin synthesis of stone cells. In this study, 31 CCRs and 26 CADs were identified in the pear genome. Phylogenetic trees for CCRs and CADs were constructed; key amino acid residues were analysed, and three-dimensional structures were predicted. Using quantitative real-time polymerase chain reaction (qRT-PCR), PbCAD2, PbCCR1, -2 and -3 were identified as participating in lignin synthesis of stone cells in pear fruit. Subcellular localization analysis showed that the expressed proteins (PbCAD2, PbCCR1, -2 and -3) are found in the cytoplasm or at the cell membrane. These results reveal the evolutionary features of the CCR and CAD families in pear as well as the genes responsible for regulation of lignin synthesis and stone cell development in pear fruit.

Effect of the PI3K/AKT signaling pathway on hypoxia-induced proliferation and differentiation of bone marrow-derived mesenchymal stem cells.

Bone marrow-derived mesenchymal stem cell (BM-MSC) transplantation has been demonstrated to be an effective way of augmenting angiogenesis of ischemic tissue. The low oxygen conditions in ischemic tissue directly affect the biological behavior of engrafted cells. However, to date, the mechanism through which hypoxia regulates self-renewal, differentiation and paracrine function of BM-MSCs remains unclear. Clarification of this mechanism would be beneficial to the use of stem cell-based therapy. The PI3K/AKT pathway has been extensively investigated for its role in cell proliferation, cell transformation, paracrine function and angiogenesis. The present study aimed to analyze the role of PI3K/AKT pathway in hypoxia-induced proliferation of BM-MSCs and their differentiation into endothelial cells in vitro by the application of LY294002, a PI3K/AKT pathway inhibitor, with cells cultured in normoxia serving as a control. The results showed that rat BM-MSCs at passage 3 and 4 displayed only few phenotypical differences in the expression of surface antigens as detected by flow cytometry. When compared with the cells treated in normoxia, the proliferation of BM-MSCs in hypoxia was promoted, a greater number of cells expressed CD31 and a higher expression of vascular endothelial growth factor was observed after culture in hypoxic conditions. However, by inhibiting with LY294002, these changes induced by hypoxia were partly inhibited. In conclusion, the present study showed that the PI3K/AKT pathway served an important role in hypoxia-enhanced in vitro proliferation of BM-MSCs and their differentiation into endothelial cells and paracrine vascular endothelial growth factor.