Rapamycin-induced β-Globin Family Locus Remodeling Regulates the Gene Switching Expression / 中国生物化学与分子生物学报

β-Thalassemia caused by abnormal coding of the β-globin gene is the most common hemoglobinopathy in many Asian countries. The in-depth study of the molecular basis and epigenetic mechanism of globin gene expression is the key to explore a new treatment for thalassemia. In this study, FAIRE (formaldehyde-assisted isolation of regulatory elements), 3C (chromosome conformation capture) and ChIP (Chromatin Immunoprecipitation) were used to investigate the three-dimensional interaction network of β-globin family gene loci and the molecular mechanism of functional regulation of gene expression during rapamycin-induced chromatin remodeling in CD4+ T cells. The results showed that the opening degree of globin gene chromatin, the interaction frequency between the gene promoter region and the regulatory element LCR (Locus control regions), and the enrichment efficiency of CTCF (CCCTC-binding factor) in the gene promoter region changed differently during the change of rapamycin treatment concentration from low to high, which led to the same change trend of the gene expression pattern. At the 10 nmol/ L concentration, chromatin accessibility and gene expression decreased (P < 0. 05). At 20 nmol/ L and 50 nmol/ L concentrations, chromatin accessibility increased and gene expression was up-regulated (P < 0. 05). In this study, the molecular mechanism of gene expression regulation of the β-globin family was expounded through this dynamic change process. Our work provides a theoretical and clinical practice basis for clinical precision treatment.

Repair of wound on hand or foot due to electrical burn using free lateral upper arm perforator flap / 中华烧伤杂志

<p><b>OBJECTIVE</b>To observe the effect of free lateral upper arm perforator flap in repairing wound on hand or foot due to electrical burn.</p><p><b>METHODS</b>Six patients with full-thickness wounds on hand or foot resulting from electrical burn were hospitalized from June 2010 to June 2013. The wounds ranged from 6.0 cm ×4.0 cm to 8.5 cm×7.5 cm in area. Free lateral upper arm perforator flaps were used to repair these defects, with flap area ranging from 9 cm ×4 cm to 12 cm × 9 cm. The donor sites in five cases were closed by suturing; the other one donor site was closed by transplantation of full-thickness skin from abdomen.</p><p><b>RESULTS</b>One flap used to repair the wound in middle finger failed due to failure of venous return, and it was repaired with full-thickness skin harvested from abdomen after dressing change. The other five flaps survived resulting in good elasticity and matched appearance of the recipient area without obvious bulkiness. Patients were followed up for 6 to 24 months. The function of the injured hands or feet recovered well, and the results of function evaluation of five hands were excellent in 2 cases, good in 2 cases, and poor in 1 case. Little scar formation with no contraction or function impairment was observed on donor site, and the result was satisfactory.</p><p><b>CONCLUSIONS</b>Free lateral upper arm perforator flap, with long vessel and less adipose tissue, is suitable for repairing small but deep wound on hand or foot due to electrical burn.</p>

Regulation of peroxisome proliferator-activated receptor β by epidermal growth factor in wound tissue of mice with full-thickness skin defect / 中华烧伤杂志

<p><b>OBJECTIVE</b>To study the effect of freeze-dried mouse epidermal growth factor (mEGF) on the expression of peroxisome proliferator-activated receptor β (PPAR-β) in mice during wound healing.</p><p><b>METHODS</b>Full-thickness skin defect with area of 1.5 cm × 1.5 cm was reproduced on both sides of the back of 70 BALB/c mice (2 wounds in each mouse). The wound on the left side in each mouse was treated with 5 µg/mL mEGF solution (experiment group), and that on the right side in each mouse was treated with saline (control group). On post injury day (PID) 7, 11, and 16, 20 mice were used for determination of wound healing rate at each time point. On PID 1, 3, 7, 11, 14, and 18, specimens of wound edge were harvested for determination of protein and gene expression of PPAR-β with immunohistochemical staining and in situ hybridization, with 10 specimens at each time point (denoted as integral absorbance value). Data were processed with t test.</p><p><b>RESULTS</b>(1) Wound healing rate. The wound healing rate in experiment group on PID 7, 11, and 16 was respectively higher than that in control group (with t value respectively 3.03, 6.05, 11.9, P values all below 0.01). (2) Immunohistochemical observation. In both groups, the PPAR-β proteins highly expressed in fibroblasts of wound granulation tissues and nuclei of keratinocytes located in wound edge at early stage after injury, and they highly expressed in newly formed epidermis and their fibroblasts in the lower layer after wound epithelization. The expression of PPAR-β protein was gradually decreased after wound healing. The expression of PPAR-β protein at each time point in experiment group was respectively higher than that in control group (with t values from 2.15 to 7.37, P < 0.05 or P < 0.01). The expression of PPAR-β protein peaked on PID 3 in experiment group [(3.46 ± 1.33) × 10(3)], which was (2.35 ± 1.09) × 10(3) in control group. (3) In situ hybridization. The expression levels of PPAR-β mRNA in both groups were up-regulated after injury, which were mainly observed in fibroblasts of wound and cytoplasm of KC in wound edge, but they were down-regulated after wound epithelization. The expression of PPAR-β mRNA at each time point in experiment group was respectively higher than that in control group (with t values from 2.35 to 6.64, P < 0.05 or P < 0.01). The expression of PPAR-β mRNA in both groups peaked on PID 3 [(7.3 ± 2.6) × 10(6), (4.5 ± 3.0) × 10(6), respectively].</p><p><b>CONCLUSIONS</b>mEGF can up-regulate the expression of PPAR-β in wound tissue of mice and promote wound healing.</p>

Application of latissimus dorsi flap in different forms in repair of skin and soft tissue defects in lower extremities / 中华烧伤杂志

<p><b>OBJECTIVE</b>To explore repair methods of skin and soft tissue defects in lower extremities with free latissimus dorsi flaps.</p><p><b>METHODS</b>Forty-two patients with wounds and soft tissue defects in lower extremities, including 4 cases on knee, 22 cases on leg, 15 cases on ankle and foot, 1 case with extensive avulsion from knee to dorsum of foot, were hospitalized in our unit from February 1996 to February 2008. Wounds or soft tissue defects were respectively repaired with latissimus dorsi musculocutaneous flaps, latissimus dorsi muscle flaps, latissimus dorsi perforator flaps with preserved vascular sleeves, 2 double-leaf segmental latissimus dorsi compound flaps after debridement. The flaps ranged from 18 cm x 8 cm to 40 cm x 18 cm in size. The donor sites were covered by skin grafting in 19 cases.</p><p><b>RESULTS</b>All wounds were healed primarily except vascular crisis occurred in 3 cases, partial necrosis of skin at donor site in 2 cases, and graft site (1 case). Follow-up for 3 to 24 months of 31 patients showed: six cases received two-stage plastic operation on account of bulkiness with trouble in wearing shoes, and mild contraction of muscular flap in 3 cases.</p><p><b>CONCLUSIONS</b>Latissimus dorsi flap in various forms can be satisfactory for repair of large skin and soft tissue defects in lower extremities.</p>

Effect of lentiviral vector encoding on triggering receptor expressed on myeloid cells 1 on expression of inflammatory cytokine in septic mice infected by Bacteroides fragilis / 中华烧伤杂志

<p><b>OBJECTIVE</b>To investigate the effect of triggering receptor expressed on myeloid cells 1 (TREM-1) vshRNA vector on expression of inflammatory cytokines and survival rate in septic mice infected by Bacteroides fragilis.</p><p><b>METHODS</b>(1) TREM-1 vshRNA vector was constructed. Bacteroides fragilis (2.5 x 10(9) CFU/mL, 0.5 mL) was intraperitoneally injected in each mouse, and septic model was reproduced after 12 hours. (2) One hundred and fifteen mice were divided into healthy control group (n = 3, HC), sepsis group (n = 28, S), TREM-1 vshRNA group (n = 28, T), TREM-1 vshRNA hd group (n = 28, Th), GFP group (n = 28, G) according to random number table. Mice in S, T, Th, G groups were firstly injected with isotonic saline, TREM-1 vshRNA 2 x 10(8) TU, TREM-1 vshRNA 1 x 10(8) TU, GFP siRNA through tail vein, and then sepsis was induced after 1 hour. Mice in HC group were injected with equal volume of isotonic saline through tail vein. Three mice in each group were sacrificed after 12 hours for determination of plasma level of TNF-alpha, IL-1 beta and IL-6, and level of TREM-1mRNA and its protein in hepatic tissue. The survival rate of other mice in each group was monitored for 72 hours. (3) In 125 mice sepsis was reproduced, among them 100 mice were injected with TREM-1 vshRNA 2 x 10(8) TU after 1, 2, 4, 6 hours through tail vein (25 mice at each time point), other 25 mice were injected with equal volume of isotonic saline as control. The survival rate of mice in each group was recorded 72 hours after injection.</p><p><b>RESULTS</b>(1) Compared with those in S group, the plasma level of TNF-alpha, IL-1 beta and IL-6 lowered in T and Th groups (P < 0.05), especially in T group, while those in G group showed no obvious difference (P > 0.05). (2) Compared with those in G group, the level of TREM-1mRNA and its protein in hepatic tissue in T and Th groups decreased (P < 0.01), especially in T group. (3) The survival rate of mice in S and G group was 16%, which was obviously lower than that in T and Th groups (76%, 44%, respectively, P < 0.05 or P < 0.01). (4) The survival rate of mice at 1, 2, 4, 6 hours after injection was 72%, 56%, 40%, 16%, respectively, while all that except at 6 hour after injection were higher significantly than that of control (P < 0.05 or P < 0.01).</p><p><b>CONCLUSIONS</b>The intervention with TREM-1 vshRNA can effectively decrease hepatic level of TREM-1 in septic mice induced by Bacteroides fragilis, inhibit inflammatory response, and improve the survival rate.</p>

Repair of nose and adjacent tissue defect deformities after burn / 中华烧伤杂志

<p><b>OBJECTIVE</b>To look for the best method of repairing nose and adjacent tissue defect after burn and observe the effect.</p><p><b>METHODS</b>Twelve patients with post-burn nose and adjacent tissue defect deformities hospitalized from January 1999 to December 2008 were repaired with expanded forehead flap, pedicled upper-arm flap, axial post-auricular reversed flow island flap, and nasolabial groove flap. Among them, 4 cases with total nasal defect, 8 cases with partial nasal defect; and 3 cases were accompanied with scars on cheek, 5 cases accompanied with scars on forehead, 5 cases accompanied with upper lip ectropion and subtotal upper lip defect. The skin flap size ranged from 3.0 cm x 1.5 cm to 10.0 cm x 8.0 cm.</p><p><b>RESULTS</b>Five cases were repaired with expanded forehead flap, 3 cases with pedicled upper-arm flap, 1 case with axial post-auricular reversed flow island flap, and 3 cases with nasolabial groove flap respectively. All the 12 flaps survived. Patients were followed up for 1 to 7 years, and nasal function and appearance were obviously improved.</p><p><b>CONCLUSIONS</b>Optimal repairing method shall be chosen to repair nasal defect after burn according to its extent, and forehead flap is preferred. Pedicled upper-arm flap and reversed flow axial post-auricular island flap can be employed if local flap and ortho-position skin flap are unavailable when obvious scar is present on face as a result of severe burn.</p>

Repair of claw hand deformity after burn / 中华烧伤杂志

<p><b>OBJECTIVE</b>To summarize methods for repair of claw hand deformity after burn.</p><p><b>METHODS</b>Ninety-seven patients with 136 claw hands after burn hospitalized from May 1992 to May 2007 were repaired with skin grafting (104 hands) and transposition of skin flap (32 hands), among which 21 hands were minor-grade, 92 hands moderate, 23 hands severe. The metacarpophalangeal joint was repaired after scar release in dorsum of hand with manual extraction reduction, release of collateral ligament and joint capsula, separation of adhesion in joint, tendon lengthening for obvious contracture. Restitution of finger flexion deformity, lysis of adhesion and grafting among first web and finger webs, repair of central slip extensor tendon or phalangeal arthrodesis were performed according to the abnormal condition after lysis of dorsal scar of hand. The metacarpophalangeal joint from 31 patients were not repaired with above methods for severe finger flexion deformity, their palmar scar were loosened and transplanted firstly, then scar in dorsum of hand were loosened, metacarpophalangeal joint were repaired, flap or skin were transferred or transplanted. General rehabilitation were performed routinely after operation.</p><p><b>RESULTS</b>The ending of flaps (4 hands) due to the scar were necrosis after transposition and healed through dressing change, other skins or flaps all survived. Most articular deformities were corrected completely or basically. Functions including palmar opposition, grasp were also recovered with satisfactory results.</p><p><b>CONCLUSION</b>Skin transplantation and transferring of skin flap with overall planning and individual isatin are the key points for repair of claw hand after burn.</p>

Expression of myeloid cell triggering receptor-1 in monocytes at early post-burn stage / 中华烧伤杂志

<p><b>OBJECTIVE</b>To investigate the expression of triggering receptor expressed on myeloid cells (TREM-1) in monocytes of burn patients at early post-burn stage, and its significance.</p><p><b>METHODS</b>The monocytes of 8 healthy volunteers (A group), 29 patients with mild and moderate burn (B group), and 9 patients with severe and very serious burns (C group) were isolated from the blood, and the THEM-1 mRNA and protein expression were determined by semi-quantitative RT-PCR and flow cytometry, respectively. The plasma levels of TNF-alpha, IL-1beta were determined by ELISA method.</p><p><b>RESULTS</b>The value of TREM-1 mRNA expression in A, B and C groups were 0.74 +/- 0.13, 1.24 +/- 0.09, and 1.46 +/-0.07, respectively, and the expression rates on cell surface in the 3 groups were (9 +/- 4)%, (51 +/- 6)%, and (71 +/- 7)%, respectively, and there were significant differences among the three groups (P = 0.000). the plasma levels of TNF-alpha and IL-1beta in B and C groups were obviously higher than that in A group (P = 0.000), and they were positively correlated to TREM-1 expression (rs = 0.68, 0.72, P = 0.000).</p><p><b>CONCLUSION</b>Increased expression of TREM-1 in monocytes of burn patients at early post-burn stage is correlated with the release of inflammatory factors, indicating that TREM-1 might contribute to the onset and development of acute inflammatory response after burns.</p>

The influence of succinic acid on the apoptosis of polymorphonuclear neutrophil in peripheral blood / 中华烧伤杂志

<p><b>OBJECTIVE</b>To investigate the influence of succinic acid on the apoptosis of polymorphonuclear neutrophil (PMN) in human peripheral blood, and to explore its role in infection.</p><p><b>METHODS</b>PMNs were incubated in vitro, and its concentration was adjusted to 5 x 10(6)/mL. Then the cells were divided into normal control group and 5,10, 20, 30 mmol/L succinic acid groups according to different concentrations of succinic acid added into the medium. The supernatant of the cultures in each groups were collected to determine the superoxide content. 1 mL cell suspension was collected from 5, 20 mmol/L succinic acid groups before treatment and at 2, 4, 6, 8, 10 post-treatment hours (PTH) for the determination of caspase-3 activity and the apoptosis rate.</p><p><b>RESULTS</b>The content of superoxide in 5, 10, 20, 30 mmol/L succinic acid groups (0.437 +/- 0.056, 0.432 +/- 0.024, 0.395 +/- 0.049, 0.386 +/- 0.010) was significantly lower than that in control group (0.505 +/- 0.028, P < 0.05). The caspase-3 activity in each group increased along with the incubation time, but was in lower concentration in 5 mmol/L succinic acid group and in higher concentration in 20 mmol/L succinic acid group when compared with that in control group (P < 0.05). The apoptosis rate of PMN in control group was (6.1 +/- 1.1)% before incubation, and it reached (13.2 +/- 2.0)% at 2 PTH, and (27.7 +/- 3.7)% at 10 PTH. The apoptosis rate of PMN in 5 mmol/L succinic acid group was lower than that in control group except that at 4 PTH (P < 0.05). On the other hand, the apoptosis rate in 20 mmol/L succinic acid group (during 4-10 PTH) were obviously higher at each time points compared with the control group (P < 0.05).</p><p><b>CONCLUSION</b>Low concentration of succinic acid can suppress the apoptosis of PMN, while high concentration of succinic acid has an opposite effect. It is known that bacteria can produce succinic acid.</p>

Repair of rabbit tendon by autologous bone marrow mesenchymal stem cells / 中华烧伤杂志

<p><b>OBJECTIVE</b>To investigate the effect of rabbit bone marrow mesenchymal stem cells (MSCs) as seed cells for the repair of tendon defect.</p><p><b>METHODS</b>The MSCs were isolated, amplified and identified by detection of surface protein CD44 mRNA. A 3 cm long defect was made in the Achilles tendon of the rabbit. The rabbits were divided into experimental (E) and control (C) groups. The autologous MSCs were implanted into a collagen-polyglycolic acid (PGA) scaffold to form a tissue-engineered tendon, which was then transplanted to bridge the defect in the E group, while only collagen-PGA was transplanted to bridge the defect in the C group. The transplanted tendon was observed grossly and microscopically at 4, 8, 12 weeks after operation.</p><p><b>RESULTS</b>The cultured MSCs exhibited positive staining of CD44 on 11 days after in vitro culture. A tendon-like tissue could be discerned at the operation site in the E group 4 weeks after operation. Tendon-like cells similar to normal tendon tissue, being axially arranged in collagen matching the mechanical direction, with uniform morphology could be seen in E group 12 weeks after operation. The newly regenerated tissue in C group adhered to the adjacent tissue and was smaller than that in E group. The collagen fibers in the regenerated tissue were loose with reticular and filiform structure, and the cells were arranged disorderly 12 weeks after the transplantation.</p><p><b>CONCLUSION</b>It is feasible to repair the tendon defect with autologous MSCs as seed cells.</p>

Effects of succinic acid on the function of in vitro cultured human fibroblasts / 中华烧伤杂志

<p><b>OBJECTIVE</b>To explore the mechanism of injurious effect of succinic acid on human fibroblast and it's role in bacteroides fragilis infection.</p><p><b>METHODS</b>In vitro cultured human fibroblasts were challenged by succinic acid in concentrations of 5, 10, 20 and 30 mmol/L (pH5.5), respectively. The cellular activity, apoptosis rate, the collagen synthesis in the supernatant of the cell culture, and the activity of caspase-3 were determined 24 hours after challenge. Isotonic saline challenged fibroblast were employed as control and the changes in the indices before and after succinic acid challenge were observed.</p><p><b>RESULTS</b>Along with the increase in the concentration of succinic acid, the fibroblast proliferation rate was decreased and so was the collagen synthesis. But the apoptosis rate and caspase-3 activity were increased. The activity of caspase-3 was markedly higher than that in normal control when the succinic acid concentration was 10-30 mmol/L. The cellular activity and collagen synthesis were significantly lower and the apoptosis rate was obviously higher than those in control group when the succinic acid concentration was 20 or 30 mmol/L (P < 0.05).</p><p><b>CONCLUSION</b>The proliferation and collagen synthesis in fibroblast culture could be significantly inhibited and the cellular apoptosis could be promoted by succinic acid. The process of wound healing of the wounds infected by bacteroides fragilis would be delayed due to the production of succinic acid by the bacteria.</p>

Clinical analysis of brain injury in patients injured by high voltage electricity / 中华烧伤杂志

<p><b>OBJECTIVE</b>To explore the pathogenic characteristics and management of brain injury in patients injured by high voltage electricity.</p><p><b>METHODS</b>One hundred and thirty eight patients injured by electricity were enrolled in this study. Postburn brain injury was diagnosed by clinical sighs and imaging analysis. The brain injury was graded as mild, moderate, severe and most severe. The relationships among the inlet of the electric current and the electric voltage and the degree of brain injury were analyzed, and the causes and pathogenesis of the brain injury were suggested. Treatment modality was optimized for the patients according to the diagnostic data.</p><p><b>RESULTS</b>In this group of patients, brain injury was identified in 106 cases, mostly rated as mild and moderate. Only 4 cases were ranked as severe degree with positive imaging findings. The electric voltage seemed to be not correlated with the incidence of postburn brain injury. But the intensity of electric current and the locations of electrical current inlet and outlet were closely related to the degree of brain injury. Among all the patients in this group, 131 survived and 7 died after treatment. But there was no death due directly to brain injury.</p><p><b>CONCLUSION</b>There was high incidence of postburn brain injury in patients injured by high voltage electricity. The injury might be related to the direct effect of electrical current on the brain tissue, to mechanical injury, to the cardio-pulmonary lesions caused by electrical current, or to massive skin burn. Early and accurate diagnosis of the injury was of key importance for lowering both mortality and disability.</p>

The influence of the LPS from Bacteroides fragilis on the secretion of IL-2 and IL-4 from the peripheral blood mononuclear cells of normal volunteers / 中华烧伤杂志

<p><b>OBJECTIVE</b>To investigate the influence of the LPS of Bacteroides fragilis on the secretion of IL-2 and IL-4 from the peripheral blood mononuclear cells of normal individuals, so as to elucidate the mechanism of the infection by Bacteroides fragilis.</p><p><b>METHODS</b>LPS was obtained from both the strains isolated from patients and from standard NCTC9343. Peripheral blood mononuclear cells (PBMCs) were treated with different concentrations of LPS thus obtained. The supernatants from the cell culture of the PBMCs were harvested at 24 PBHs and were subjected to the determination of the IL-2 and IL-4 contents by ELISA method. RESULTS The IL-2 secretion from the PBMCs of normal volunteers was obviously inhibited by the LPS from Bacteroides fragilis (P < 0.01), and the inhibitory effect was dose-dependent. Nevertheless, the IL-4 secretion from the PBMCs of normal volunteers was significantly stimulated by the LPS from Bacteroides Fragilis (P < 0.05), and it was not concentration dependent. There was no difference between the effects of the LPSs from patients and standard strains (P < 0.05).</p><p><b>CONCLUSION</b>The LPS from Bacteroides fragilis was inhibitory to the secretion of IL-2 from PBMCs and was stimulative to that of IL-4 from PBMCs of normal human persons.</p>

Advances on Polyketide Biosynthesise by Microorganism and the Diversity of Polyketide Synthases / 微生物学通报

Polyketides are very large group of natural products with functional and structural diversity.Most of them are produced by microor- ganism and have medicinal activities,including antibiotic,anticancer,antifungal and antiparasitic properties.The researchs in this area have progressed greatly.More and more polyketides are discovered,on the other hand the mechanisms of biosynthesis of those various polyketides are researched more deeply and clearly.The article reviewed the progress of the research in the diversity of polyketide synthases and the mechanisms of polyketide biosynthesise.