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.

proBDNF Attenuates Hippocampal Neurogenesis and Induces Learning and Memory Deficits in Aged Mice.

Mature brain-derived neurotrophic factor has shown promotive effect on neural cells in rodents, including neural proliferation, differentiation, survival, and synaptic formation. Conversely, the precursor of brain-derived neurotrophic factor (proBDNF) has been emerging as a differing protein against its mature form, for its critical role in aging process and neurodegenerative diseases. In the present study, we investigated the role of proBDNF in neurogenesis in the hippocampal dentate gyrus of aged mice and examined the changes in mice learning and memory functions. The results showed that the newborn cells in the hippocampus revealed a significant decline in proBDNF-treated group compared with bovine serum albumin group, but an elevated level in anti-proBDNF group. During the maturation period, no significant change was observed in the proportions of phenotype of the newborn cells among the three groups. In water maze, proBDNF-treated mice had poorer scores in place navigation test and probe test, compared with those from any other group. Thus, we conclude that proBDNF attenuates neurogenesis in the hippocampus and induces the deficits in learning and memory functions of aged mice.

Multifunctional uranyl hybrid materials: structural diversities as a function of pH, luminescence with potential nitrobenzene sensing, and photoelectric behavior as p-type semiconductors.

A series of uranyl-organic frameworks (UOFs), {[(UO2)2(H2TTHA)(H2O)]·4,4'-bipy·2H2O}n (1), {[(UO2)3(TTHA)(H2O)3]}n (2), and {[(UO2)5(TTHA) (HTTHA)(H2O)3]·H3O}n (3), have been obtained by the hydrothermal reaction of uranyl acetate with a flexible hexapodal ligand (1,3,5-triazine-2,4,6-triamine hexaacetic acid, H6TTHA). These compounds exhibited three distinct 3D self-assembly architectures as a function of pH by single-crystal structural analysis, although the used ligand was the same in each reaction. Surprisingly, all of the coordination modes of the H6TTHA ligand in this work are first discovered. Furthermore, the photoluminescent results showed that these compounds displayed high-sensitivity luminescent sensing functions for nitrobenzene. Additionally, the surface photovoltage spectroscopy and electric-field-induced surface photovoltage spectroscopy showed that compounds 1-3 could behave as p-type semiconductors.

Synthesis, crystal structure, photoluminescence property of a series of 3d-4f coordination supramolecular complexes.

A series of 3d-4f heterobinuclear complexes were constructed by employing the 2,2'-bipy (2,2'-bipy=2,2'-bipyridine) ligand and corresponding metal ions (M(II)/Ln(III), M=Co(II), Cu(II) and Zn(II); Ln(III)=Nd(III), Sm(III), Eu(III) and Tb(III)). Elemental analyses, IR, UV-vis-NIR spectra, PXRD and single crystal X-ray diffraction analysis reveal that complexes 1-4, 5-8, and 9-12 are isomorphous, respectively. The zero-dimensional structures are further connected to 2D or 3D supramolecular network structures via extensive intermolecular hydrogen bonds. Luminescence studies for the heterobinuclear complexes containing Sm(III), Eu(III) and Tb(III) reveal that the chromophoric composed of Zn(II)/L may efficiently sensitize the luminescence of the rare earth cations which acts as an antenna, whereas the existence of Cu(II) leads to the quenching of the luminescence of Ln(III) ions.

Hierarchically clustering to 1,033 genes differentially expressed in mouse superior colliculus in the courses of optic nerve development and injury.

Tempo spatially specific expression of many development-related genes is the molecular basis for the formation of the central nervous system (CNS), especially those genes regulating the proliferation, differentiation, migration, axon growth, and orientation of nerve cells. The development-related genes are usually prominent during the embryonic and newborn stages, but rarely express during the adulthood. These genes are believed to be suitable target genes for promoting CNS regeneration, despite majority of which remains unknown. Hence, the aim of this study was to screen development-related genes which might contribute to CNS regeneration. In this study, 1,033 differentially-expressed genes of superior colliculus in the courses of mouse optic nerve development and injury, as previously identified by cDNA microarrays, were hierarchically clustered to display expression pattern of each gene and reveal the relationships among these genes, and infer the functions of some unknown genes based on function-identified genes with the similar expression patterns. Consequently, the expression patterns of 1,033 candidate genes were revealed at eight time points during optic nerve development or injury. According to the similarity among gene expression patterns, 1,033 genes were divided into seven groups. The potential function of genes in each group was inferred on the basis of the dynamic trend for mean gene expression values. Moreover, the expression patterns of six function-unidentified genes were extremely similar to that of the ptn gene which could promote and guide axonal extension. Therefore, these six genes are temporally regarded as candidate genes related to axon growth and guidance. The results may help to better understand the roles of function-identified genes in the stages of CNS development and injury, and offer useful clues to evaluate the functions of hundreds of unidentified genes.

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>

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>

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>

[Evaluation of the protection conferred by several avian infectious bronchitis attenuated vaccines against the field strain CK/CH/LDL/97 I in China].

The entire S1 protein gene of five infectious bronchitis (IB) vaccine strains (JAAS, IBN, Jilin, J9, H120) used in China were compared with that of the IB field isolate CK/CH/LDL/97 I present in China. The nucleotide and deduced amino acid similarities between the five IB vaccine strains and the field strain, CK/CH/LDL/97 I, were not more than 76.4% and 78.7%, respectively. Phylogenetic analysis based on the S1 gene showed that the vaccine strains and the field strain belonged to different clusters and had larger evolutionary distances, indicating that they were of different genotypes. The five vaccine strains were used for protection test against challenge of the field isolate CK/CH/LDL/97 I. The chickens inoculated with five vaccine strains showed morbidity as high as 30%-100% after challenged with the CK/CH/ LDL/97 I strain. The organ samples at 5 days post challenge showed that the viral detection rates were 50%-90% and 10%-30% for trachea and kidney, respectively. The live attenuated vaccines only provided partial protection to the vaccinated chickens against heterologous IBV infection, CK/CH/LDL/97 I.

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>

Photoluminescence enhancement in Yb(3+):Er(3+)co-doped eutectic Al(2)O(3): SiO(2) thin films by 980nm excitation.

Si nanocrystals (nc-Si) are addressed in the eutectic Al(2)O(3):SiO(2) thin films co-doped with Er(3+) and Yb(3+) by the laser-induced crystallization (LIC). The thin films are originally synthesized on a silica-on-silicon (SOS) substrate by the microwave electron cyclotron resonance (MW-ECR) plasma source enhanced RF sputtering. Raman spectroscopy has revealed that the strong crystallization occurs with the emergence of the nc-Si in the eutectic Al(2)O(3): SiO(2) layer during the liquid phase transformation. The dual wavelength energy transfer mechanism at 800nm and 980nm induced by 980nm excitation in nc-Si and Yb sensitized Er doped system has been proposed and demonstrated. A tenfold photoluminescence enhancement has been obtained from this mechanism.

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 spinal cord injury by neural stem cells modified with BDNF gene in rats.

Objective To explore repair of spinal cord injury by neural stem cells (NSCs) modified with brain derived neurotrophic factor (BDNF) gene (BDNF-NSCs) in rats. Methods Neural stem cells modified with BDNF gene were transplanted into the complete transection site of spinal cord at the lumbar 4 (L4) level in rats. Motor function of rats' hind limbs was observed and HE and X-gal immunocytochemical staining, in situ hybridization, and retrograde HRP tracing were also performed. Results BDNF-NSCs survived and integrated well with host spinal cord. In the transplant group, some X-gal positive, NF-200 positive, GFAP positive, BDNF positive, and BDNF mRNA positive cells, and many NF-200 positive nerve fibers were observed in the injury site. Retrograde HRP tracing through sciatic nerve showed some HRP positive cells and nerve fibers near the rostral side of the injury one month after transplant and with time, they increased in number. Examinations on rats' motor function and behavior demonstrated that motor function of rats' hind limbs improved better in the transplant group than the injury group. Conclusion BDNF-NSCs can survive, differentiate, and partially integrate with host spinal cord, and they significantly ameliorate rats ' motor function of hind limbs, indicating their promising role in repairing spinal cord injury.

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>

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>

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>