[Morphological and biochemical characterization during seed development of Notopterygium incisum].

This study aimed to examine the morphological, physiological, and biochemical alterations occurring in Notopterygium incisum seeds throughout their developmental stages, with the objective of establishing a theoretical foundation for the cultivation of superior quality seeds. The experimental materials utilized in this study were the seeds of N. incisum at various stages of development following anthesis. Through the employment of morphological observation and plant physiology techniques, the external morphology, nutrients, enzyme activity, and endogenous hormones of the seeds were assessed. The results revealed a transition in seed coat color from light green to brown during the growth and development of N. incisum seeds. Additionally, as the seeds matured, a decrease in water content was observed. Conversely, starch content exhibited a progressive increase, while sucrose content displayed fluctuations. At 7 days after anthesis, the soluble sugar content attained its highest level of 4.52 mg·g~(-1), whereas the soluble protein content reached its maximum of 6.00 mg·g~(-1) at 14 days after anthesis and its minimum of 4.94 mg·g~(-1) at 42 days after anthesis. The activity of superoxide dismutase(SOD) exhibited an initial increase, followed by a decrease, and eventually reached a stable state. Conversely, the activities of catalase(CAT) and peroxidase(POD) demonstrated a decrease initially, followed by an increase, and then another decrease. The levels of the four endogenous hormones, namely gibberellin(GA_3), zeatin riboside(ZR), auxin(IAA), and abscisic acid(ABA), in the seeds displayed significant variations, with IAA and ABA exhibiting considerably higher levels compared to the other hormones. The levels of plant growth-promoting hormones, represented by IAA, generally displayed a pattern of initial increase followed by a subsequent decrease during seed development, while the plant growth-inhibiting hormone ABA showed the opposite trend. The findings indicate that the alterations in nutrient composition, antioxidant enzyme activity, and endogenous hormone levels vary throughout the maturation process of N. incisum seeds. These observations hold relevance for the cultivation of N. incisum seeds.

Porous Se@SiO2 nanoparticles improve oxidative injury to promote muscle regeneration via modulating mitochondria.

Background: Acute skeletal muscle injuries are common among physical or sports traumas. The excessive oxidative stress at the site of injury impairs muscle regeneration. The authors have recently developed porous Se@SiO2 nanoparticles (NPs) with antioxidant properties. Methods: The protective effects were evaluated by cell proliferation, myogenic differentiation and mitochondrial activity. Then, the therapeutic effect was investigated in a cardiotoxin-induced muscle injury rat model. Results: Porous Se@SiO2 NPs significantly protected the morphological and functional stability of mitochondria, thus protecting satellite cells from H2O2-induced damage to cell proliferation and myogenic differentiation. In the rat model, intervention with porous Se@SiO2 NPs promoted muscle regeneration. Conclusion: This study reveals the application potential of porous Se@SiO2 NPs in skeletal muscle diseases related to mitochondrial dysfunction.

Muscle injuries are very common in daily life and in sports. When a muscle is injured, the local response inhibits the regeneration and differentiation of stem cells inside the muscle, thus hindering muscle regeneration. The authors have recently developed a nanoparticle with the ability to protect muscle stem cell function, promote stem cell proliferation and differentiation and facilitate muscle regeneration after skeletal muscle injury in rats. Thus, this study reveals the potential of porous Se@SiO₂ nanoparticles in skeletal muscle diseases associated with mitochondrial dysfunction.

Air Pollution Exposure and Risk of Spontaneous Pneumothorax in Children: A Longitudinal, Nationwide Study.

Spontaneous pneumothorax (SP) involves the spontaneous appearance of air in the pleural space. Atmospheric pressure, temperature change, and seasonal factors may precipitate SP, but its association with air pollution remains unclear. Therefore, we conducted this nationwide, retrospective population-based study to evaluate the risk of SP in Taiwanese children exposed to air pollution. We collected data on SP incidence from the Longitudinal Health Insurance Database; the Taiwan Air Quality-Monitoring Database provided daily concentrations of nitric oxide (NO), nitrogen dioxide (NO2), and hydrocarbons in 2000-2012. SP risk was evaluated for four quartiles (Q1, Q2, Q3, Q4). The NO adjusted hazard ratios (aHRs) for Q2, Q3, and Q4 compared to Q1 were 1.11 (95% confidence interval (CI): 0.77-1.61), 1.24 (95% CI: 0.88-1.76), and 1.66 (95% CI: 1.17-2.34), respectively. The NO2 aHRs for Q2, Q3, and Q4 were 1.12 (95% CI: 0.77-1.64), 1.31 (95% CI: 0.0.90-1.90), and 1.51 (95% CI: 1.04-2.19), respectively. Hydrocarbons aHRs for Q2, Q3, and Q4 were 0.87 (95% CI: 0.64-1.18), 1.16 (95% CI: 0.90-1.49), and 1.40 (95% CI: 1.06-1.85), respectively. Increased exposure to NO, NO2, and hydrocarbons is associated with increased SP risk in Taiwanese children.

Allicin can suppress the activity of vascular endothelial cells probably by regulating JAK2/STAT3 pathway.

Whether allicin can suppress the angiogenesis via inhibiting the activity of vascular endothelial cells (VECs) in preventing epidural hypertrophic scars remains unknown. VECs were treated by allicin at a gradient of concentrations. Cell activity was measured by CCK-8 assay, scratch assay and flow cytometry. Reverse-transcription PCR and Western Blot were used to measure the expression levels of relevant genes and proteins. After treated with allicin at concentrations of 0, 25, 50 and 100 mg/L, the viability of VECs significantly decreased at 24 h (p < 0.001*) and 48 h (p < 0.001*), and migration rate significantly decreased in scratch assay (p = 0.017*) and in Transwell assay (p = 0.021*). As the concentrations of allicin increased, the apoptosis rate of VECs rose up (p = 0.018*). There was no significant difference on cell numbers at S phase (p = 0.25), but cell numbers at G1 phase decreased (p = 0.039*) and at G2 phase increased (p = 0.047*). With the increase of allicin concentrations, the ability of tube formation for VECs significantly decreased (p < 0.001*). Comparing with control group, the expression of PCNA and BCL-2 decreased (p < 0.001*), while the expression of BAX increased significantly (p < 0.001*). Regarding to JAK2/STAT3 pathway, the expression levels of JAK3 and STAT3 decreased significantly with the increase of allicin concentrations (p < 0.001*). Allicin can suppress the activity of VECs probably by regulating JAK2/STAT3 pathway.

[Anatomical and tensile mechanical analysis of hip joint capsule repair in total hip replacement].

OBJECTIVE: To explore the tensile mechanics and anatomical characteristics of the posterior hip capsule, and provide biomechanical and anatomical evidence for capsule repair in total hip replacement. METHODS: Six bone-capsule-bone specimens were obtained from posterior hip joint of fresh frozen cadavers. The maximum strain, load, elastic modulus and load strain curves of the capsule ligament complex specimens were recorded by Instron Universal Material Testing Machine. Twelve cadaveric hip specimens were dissected to the capsule. The tensile strain of normal capsule and conventionally reconstructed capsule at 90 degrees of hip flexion were documented. The suture area of the posterior capsule was divided into nine sections, and the thicknessof different sections was measured and compared. Posterior capsule of the cadavers was repaired in conventionally way and anatomical way separately and simulated rehabilitation was conducted. The effect of rehabilitation on the repaired capsule was observed. RESULTS: The load-strain curve of capsule ligament complex conforms to rheological and viscoelastic characteristics. The maximum tensile strain of the complex was (39.21±5.23)%, the maximum load was (142.06± 34.15) N, the tensile strength was (1.65±0.38) MPa, and the elastic modulus is (14.23±5.62) MPa. At 90 ° hip flexion, the tensile strain of repaired capsule was higher than that of normal capsule, and the difference was statistically significant (P< 0.05). Tensile strain of conventionally reconstructed capsule is:upper part (37.0±4.9)%, middle part ( 53.3±1.1)%, lower part (68.3±6.2)%, tensile strain of normal capsule is:upper part (17.0±2.6)%, middle part (24.1±1.4)%, lower part (26.0± 4.3)% . The thickness of the posterior joint capsulein different sections is statistically significant (P<0.05), and capsule at 0.5cm proximal to the femoral insertion is suitable for suture. There the average thickness of capsule is:upper part (3.48 ± 0.11) mm, middle part (2.36 ± 0.09) mm, lower part (1. 59±0.24) mm. The posterior inferior joint capsule is thinnest at (1.42± 0.02) cm proximal to the femoral insertion, and sutures should be avoided here. After simulating rehabilitation, avulsion occurred in the lower part of the posterior capsule repaired conventionally (10/12), and the anatomically repaired capsule remained intact. CONCLUSION: The lower part of conventionally repaired capsule is overstretched and tends to fail. Anatomically repaired capsule conforms to tensile mechanics and is helpful to reduce the failure rate of repair.

The effect of high glucose on the biological characteristics of nucleus pulposus-derived mesenchymal stem cells.

Diabetes mellitus (DM) is a dependent risk factor in the progression of intervertebral disc degeneration (IVDD). High glucose supply has negative effects on nucleus pulpous (NP) cell and mesenchymal stem cell (MSC) biology. However, the effect of hyperglycaemia on the biological characterization of nucleus pulpous-derived mesenchymal stem cell (NPMSC) has not been investigated previously. Therefore, further exploration of the effects of DM-associated hyperglycaemia on NPMSC biology is important to better understand and develop endogenous repair strategies of DM patient-associated IVDD. Therefore, the cell biological characteristics were compared between NPMSC cultured in media with low glucose concentration (LG-NPMSC) and high glucose concentration (HG-NPMSC). The results demonstrated that HG-NPMSC showed significantly decreased cell proliferation, colony formation ability, migration and wound-healing capability compared with those of LG-NPMSC. HG-NPMSC also showed significantly decreased expressions of stemness genes and mRNA and protein expressions of silent information regulator protein 1 (SIRT1), SIRT6, hypoxia inducible factor-1α (HIF-1α) and glucose transporter 1 (GLUT-1), whereas increased cell apoptosis, cell senescence and caspase-3 expression. These results suggest that high glucose may decrease proliferation and stemness maintenance ability and increase apoptosis and senescence of NPMSC. SIGNIFICANCE OF THE STUDY: We found that high glucose concentration significantly decreased cell proliferation, colony formation ability, migration and wound-healing capability of nucleus pulposus-derived mesenchymal stem cells. Moreover, high glucose cultured nucleus pulposus-derived mesenchymal stem cells showed significantly decreased expression of stemness genes, related mRNA and protein, whereas increased cell apoptosis, cell senescence and expression of caspase-3. The present study indicated that better control of high concentration glucose in the early stage of diabetes mellitus should be recommended to prevent or limit intervertebral disc degeneration.

Allicin Inhibits Proliferation and Promotes Apoptosis of Human Epidural Scar Fibroblasts.

BACKGROUND: Allicin can suppress liver and cardiac fibrosis; thus, we hypothesized that it might prevent scar tissue from extensive epidural fibrosis after laminectomy. METHODS: Human epidural scar fibroblasts were isolated from surgical specimens and treated with allicin at a gradient of concentrations. Morphology, viability, migration rate, cell cycle, and apoptosis rate were measured by fluorescence microscope, Cell Counting Kit-8 assay, scratch assay, and flow cytometry. Western blot was used to measure the expression level of proliferation-related proteins. RESULTS: After treatment by allicin, cell viability (P = 0.042) and migration rate (P = 0.010 in scratch assay and P = 0.025 in transwell assay) decreased significantly in a dose-dependent manner. The percentage of G1 phase cells significantly decreased (P = 0.017), whereas the percentage of S phase cells (P = 0.096) and G2 phase cells (P = 0.038) significantly increased in a dose-dependent manner. Similarly, the percentage of apoptotic cells increased significantly in a dose-dependent manner (P = 0.036). Compared with the control group, the expression level of proliferating cell nuclear antigen protein (P = 0.081) and Bcl-2 protein (P = 0.029) significantly decreased, whereas the BAX protein level significantly increased (P = 0.017). CONCLUSIONS: Allicin can suppress human epidural scar fibroblast migration, induce cell apoptosis, and block cell proliferation at S phase and G2 phase.

Naringin alleviates H2O2-induced apoptosis via the PI3K/Akt pathway in rat nucleus pulposus-derived mesenchymal stem cells.

Purpose: To investigate the protective effect of naringin (Nar) on H2O2-induced apoptosis of nucleus pulposus-derived mesenchymal stem cells (NPMSC) and the potential mechanism in this process. Methods: Rat NPMSC were cultured in MSC culture medium or culture medium with different concentrations of H2O2. Nar or the combination of Nar and LY294002 was added into the culture medium to investigate the effects of Nar. Cell viability was evaluated by cell counting kit-8 (CCK-8) assay. The apoptosis rate was determined using Annexin V/PI dual staining and terminal deoxynucleotide transferase-mediated dUTP nick end labeling (TUNEL) assays. Additionally, the levels of reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) were analyzed by flow cytometry. ATP level in NPMSC was analyzed via ATP detection kit. Mitochondrial ultrastructure change was observed through transmission electron microscope (TEM). Levels of apoptosis-associated molecules (cleaved caspase-3, Bax and Bcl-2) were evaluated via RT-PCR and western blot, respectively. Results: The cells isolated from NP met the criteria for MSC. H2O2 significantly promoted NPMSC apoptosis in a dose and time-dependent manner. Nar showed no cytotoxicity effect on NPMSC up to a concentration of 100 µM for 24 h. Nar exhibited protective effects against H2O2-induced NPMSC apoptosis including apoptosis rate, expressions of proapoptosis and antiapoptosis related genes and protein. Nar could also alleviate H2O2-induced mitochondrial dysfunction of increased mitochondrial ROS production, reduced MMP, decreased intracellular ATP and mitochondrial ultrastructure change. However, these protected effects were inhibited after LY294002 treatment. Conclusions: Our results demonstrated that Nar efficiently attenuated H2O2-induced NPMSC apoptosis and mitochondrial dysfunction. The activation of ROS-mediated PI3K/Akt pathway may be the potential mechanism in this process.

Injectable Hydrogel Combined with Nucleus Pulposus-Derived Mesenchymal Stem Cells for the Treatment of Degenerative Intervertebral Disc in Rats.

Stem cell-based tissue engineering in treating intervertebral disc (IVD) degeneration is promising. An appropriate cell scaffold can maintain the viability and function of transplanted cells. Injectable hydrogel has the potential to be an appropriate cell scaffold as it can mimic the condition of the natural extracellular matrix (ECM) of nucleus pulposus (NP) and provide binding sites for cells. This study was aimed at investigating the effect of injectable hydrogel-loaded NP-derived mesenchymal stem cells (NPMSC) for the treatment of IVD degeneration (IDD) in rats. In this study, we selected injectable 3D-RGD peptide-modified polysaccharide hydrogel as a cell transplantation scaffold. In vitro, the biocompatibility, microstructure, and induced differentiation effect on NPMSC of the hydrogel were studied. In vivo, the regenerative effect of hydrogel-loaded NPMSC on degenerated NP in a rat model was evaluated. The results showed that NPMSC was biocompatible and able to induce differentiation in hydrogel in vivo. The disc height index (almost 87%) and MRI index (3313.83 ± 227.79) of the hydrogel-loaded NPMSC group were significantly higher than those of other groups at 8 weeks after injection. Histological staining and immunofluorescence showed that the hydrogel-loaded NPMSC also partly restored the structure and ECM content of degenerated NP after 8 weeks. Moreover, the hydrogel could support long-term NPMSC survival and decrease cell apoptosis rate of the rat IVD. In conclusion, injectable hydrogel-loaded NPMSC transplantation can delay the level of IDD and promote the regeneration of the degenerative IVD in the rat model.

The effect of intervertebral disc degenerative change on biological characteristics of nucleus pulposus mesenchymal stem cell: an in vitro study in rats.

Purpose: To evaluate the change on biological characteristics of mesenchymal stem cell (MSC) derived from normal and degenerative intervertebral disc (IVD). Methods: MSC was isolated from normal and degenerative IVD rat model. Immunophenotype detected by flow cytometric analysis, expression of stemness genes determined by reverse-transcription polymerase chain reaction (RT-PCR) and osteogenic, adipogenic and chondrogenic differentiation were compared between MSC derived from normal IVD (N-NPMSC) and degenerative IVD (D-NPMSC). The biological characteristics including cell proliferation, colony formation, apoptosis, caspase-3 activity and mRNA and protein expressions of hypoxia inducible factor-1α (HIF-1α), glucose transporter 1 (GLUT-1), vascular endothelial growth factor (VEGF), silent information regulator protein 1 (SIRT1) and silent information regulator protein 6 (SIRT6) were compared between N-NPMSC and D-NPMSC. Results: Both of N-NPMSC and D-NPMSC highly expressed CD105, CD90 and CD73, and lower expressed CD34 and CD45. There was no significant difference in cell morphology and multipotent differentiation ability between N-NPMSC and D-NPMSC. D-NPMSC showed significantly lower expressions of stemness genes, cell proliferation and colony formation ability. D-NPMSC also exhibited increased cell apoptosis rate and caspase-3 expression, and significantly lower expressions of HIF-1α, GLUT-1, VEGF, SIRT1 and SIRT6 in mRNA and protein levels compared with N-NPMSC. Conclusions: N-NPMSC showed significantly higher proliferation rate, better colony forming and stemness maintenance ability, whereas reduced cell apoptosis rate compared with D-NPMSC. HIF-1α-mediated signal pathway may be involved in the regulation of NPMSC proliferation. These findings indicated that degenerative change of IVD should be taken into account when selecting a source of NPMSC for clinical application.

Efficacy and safety of baricitinib for active rheumatoid arthritis in patients with an inadequate response to conventional synthetic or biological disease-modifying anti-rheumatic drugs: A meta-analysis of randomized controlled trials.

The purpose of the present meta-analysis was to assess the efficacy and safety of baricitinib for active rheumatoid arthritis (RA) in patients with an inadequate response or intolerance to conventional synthetic or biological disease-modifying anti-rheumatic drugs (DMARDs). A total of 7 randomized controlled trials (RCTs) were included. The primary effective outcome was the RA improvement to reach an American College of Rheumatology 20% (ACR20) response rate. The safety outcomes were composed of clinical laboratory parameters. All patients included received 4 mg baricitinib once daily to treat RA for 12 or 24 weeks. The ACR20 response rate in the baricitinib group was significantly higher compared with that in the control group at 12 weeks [relative risk (RR), 1.77; 95% confidence interval (CI), 1.62-1.94; P<0.00001] and 24 weeks (RR, 1.76; 95% CI, 1.48-2.10; P<0.00001). Similarly, other effective outcome measures also exhibited significant improvements in the baricitinib group compared with those in the placebo group. Regarding the safety outcomes, no significant difference in adverse events (AEs) was identified at 12 weeks (P=0.14), but AEs were significantly higher in the baricitinib group compared with those in the control group at 24 weeks (P=0.03). Most laboratory values were significantly different between the baricitinib and placebo groups; however, the clinical significance of these changes remains to be determined. In summary, the present meta-analysis demonstrated that 4 mg baricitinib once daily was beneficial in patients with active RA with an inadequate response or intolerance to conventional synthetic or biological DMARDs. More high-quality RCTs are required to determine the sustained efficacy and the safety of baricitinib.

[Classification and treatment of syndesmotic injury].

The distal tibiofibular syndesmosis is a critical structure in maintaining the ankle stability. Syndesmotic injuries are usually associated with ankle fractures and high fibula fractures. Non-isolated and partially isolated syndesmotic injuries are involved in unstable injuries, which need to operative treatment. Partially isolated syndesmotic injuries belong to stable injuries, which should be treated with non-operative management. It is becoming clear that early fixation and stabilization for unstable injuries are probably better than non-treatment or delayed treatment. It still remains without consensus of accurately defining stable from unstable injuries and sufficiently differentiating between acute and chronic injuries. Because of stability, fixation type, and duration, the clinical efficacy is different. Screw fixation is a gold standard treatment of syndesmotic injury. However, it remains controversial that whether removal of the syndesmotic screw is required and effect of the level of syndesmotic screw insertion, limited micro-movement is one of disadvantages of screw fixation. Micro-movement of the distal tibiofibular syndesmosis has been paid more and more attention. Dynamic fixation is a viable alternative to the static fixation device, with lower re-operation rates and less complications, which has obtained a great short-term clinical efficacy. However, further long-term studies should be carried out to confirm this clinical efficacy. Optimized treatment strategies considering stability of syndesmotic injury, duration, and fixation type can help to improve clinical efficacy.

Comparison of navigated and conventional high tibial osteotomy for the treatment of osteoarthritic knees with varus deformity: A meta-analysis.

BACKGROUND: High tibial osteotomy (HTO) is a usefully surgical procedure to correct the malalignment and delay the progression of osteoarthritis. It is still controversy whether navigation system can offer more accuracy of targeted alignment and achieve better clinical outcomes than conventional method. The purpose of present meta-analysis was to investigate whether navigation system was superior to conventional method with regard to clinical and radiographic outcomes. METHOD: The included studies compared the clinical and radiographic outcomes between navigated HTO group and conventional group. The clinical assessments were Lysholm Score, AKS Function Score and Arc of motion, and the radiographic outcomes were Mechanical axis (MA), Weight bearing line ratio (WBL), Outliers of alignment and Change in TPS used to evaluate alignment correction. The meta-analysis was performed using Review Manager 5.3 software. Downs and Black and the Newcastle-Ottawa Scale (NOS) were used to evaluate the study quality. RESULT: Sixteen studies were eligible in present meta-analysis, including thirteen studies concerning opening wedge HTO and three studies involving closing wedge HTO. Clinical outcomes were only reported in studies which used opening wedge HTO. No significant differences were observed in all clinical outcomes between navigated and conventional HTO. Regarding radiographic outcomes, no significant difference in WBL ratio was observed between navigated and conventional HTO. Patients undergoing navigated HTO were associated with significantly greater in MA and lower in Outliers of alignment compared with those undergoing conventional HTO. Compared with conventional HTO, increase in TPS was significantly lower in navigated HTO group using opening wedge HTO, but decrease in TPS was significantly greater in navigated HTO group using closing wedge HTO. CONCLUSION: Our meta-analysis demonstrated that navigated HTO offered more accuracy and precision of alignment correction, except WBL ratio. However, better clinical outcomes were not observed in navigation group.

Proliferative Constituents from the Leaves of Micromelum integerrimum.

Two new compounds, 5-O-methyl-4-desmethyl-myricanol (1) and 6-formyl-5-isopropyl-3-hydroxymethyl-7-methyl-1H-indene (2), were isolated from the leaves of Micromelum integerrimum. Their structures were determined by spectroscopic methods. Additionally, compound 1 could stimulate the growth of NIH3T3 cells and promote cell migration. Compound 1 might exert its effects through increasing the protein expression of connective tissue growth factor.

Preparation and testing of quaternized chitosan nanoparticles as gene delivery vehicles.

The aim of this study was to synthesize a chitosan (CS) derivative, a quaternary ammonium salt crystal called N-2-hydroxypropyl trimethyl ammonium chloride chitosan (HACC), and test a series of HACC and pEGFP-DNA complexes at different weight ratios for their efficiency of gene delivery into human cells. CS was modified with cationic etherifying agent to obtain the CS derivative. Fourier transform infrared spectra were recorded on KBr pellets with a spectrometer. (1)H nuclear magnetic resonance (NMR) spectra of HACC were obtained using a spectrometer. HACC was subsequently used to prepare HACC/DNA complexes at different weight ratios by coacervation method. The resulting particle size and surface charge were assessed by laser light scattering using a zeta potential analyzer. The HACC/DNA complex formation and DNA protection in the nanoparticle complex was investigated by gel mobility shift assay and DNase I protection assay, respectively. The cytotoxicity of HACC and HACC/DNA nanoparticles was evaluated by MTT assay using (mesenchymal stem cell) MSC lines. The nanoscale structure of the particles was obtained by transmission electron microscope (TEM). The FTIR spectrum of HACC showed the characteristic quaternary ammonium group absorption band at 1475 cm(-1), which indicated the presence of quaternary ammonium group. The successful synthesis of HACC was also confirmed by (1)H NMR spectrum. HACC showed good solubility in water and was electropositive. HACC efficiently packed and protected pEGFP-DNA at a weight ratio of 10. With increased weight ratios, the surface charge of the composite particle increased from negative to positive, the average particle size increased, and HACC nanoparticle had a higher carrying efficiency. The nanoparticles released DNA in two distinct phases, and 55 % was released within the first 20 h of solubilization. The nanoparticles under TEM showed circular or oval shapes. The particles exhibited no cytotoxicity against human cells. No significant difference in gene delivery efficiency was detected between HACC/pEGFP-GDNF and liposome/pEGFP-GDNF complexes (33.8 vs. 34 %, P = 0.363). In this study, HACC was successfully synthesized, and HACC/DNA complex assembled efficiently. HACC showed strong DNA binding affinity and high protection of DNA and was non-cytotoxic to human cells. The particles had appropriate nanostructure, mean diameter, and DNA release time. The results suggest that HACC nanoparticles are a novel tool for efficient and safe gene delivery.

The isolation and cultivation of bone marrow stem cells and evaluation of differences for neural-like cells differentiation under the induction with neurotrophic factors.

The bone marrow represents the most common source from which to isolate mesenchymal stem cells (MSCs). They can be obtained directly from patients and successfully induced to form various differentiated cell types. In addition, cell-based transplantation therapies have been proven to be promising strategies for curing disease of the nerve system. Therefore, it was particularly important to establish an easy and feasible method for the isolation, purification, and differentiation of bone marrow stromal cells (BMSCs). The aim of this study was to isolate and characterize putative bone marrow derived MSCs from Sprague-Dawley (SD) rats. Furthermore, differentiation effects were compared between the GDNF-induction group and the BDNF-induction group. Of these, BMSCs were isolated from the SD rats in a traditional manner, and identified based on plastic adherence, morphology, and surface phenotype assays. After induction with GDNF and BDNF, viability of BMSCs was detected by MTT assay and neuronal differentiation of BMSCs was confirmed by using immunofluorescence and Western blotting. Besides, the number of BMSCs that obviously exhibited neuronal morphology was counted and the results were compared between the GDNF-induction group and BDNF-induction groups. Our results indicate that direct adherence was a simple and convenient method for isolation and cultivation of BMSCs. Furthermore, BMSCs can be induced in vitro to differentiate into neuronal cells by using GDNF, which could achieve a more persistent and stable inducing effect than when using BDNF.

Aesthetic and sensory reconstruction of finger pulp defects using free toe flaps.

BACKGROUND: This study illustrates aesthetic and sensory reconstruction of finger pulp defects with free toe flaps from the lateral aspect of the great toe or the medial aspect of the second toe. METHODS: Between August 2007 and July 2010, free toe flaps were harvested and used for 21 fingers of 21 patients. The average patient age was 34.5 years (range 19-62 years). The soft tissue defects were found in the thumb of 6 patients, the index finger of 7 patients, the middle finger of 5 patients, and the ring finger of 3 patients. The donor site was the great toe for 9 patients and the second toe for 12 patients. The average flap size was 2.8 × 2.0 cm (range 1.7 × 1.7 to 3.5 × 3.0 cm). Restoration of the sensitivity, aesthetic appearance, and mobility of the injured fingers compared with the opposite side was assessed using appropriate tools during the follow-up time. RESULTS: All the flaps in this series survived completely, with a high survival rate of 100 %. No urgent operative revision necessitated by postoperative thrombosis of the vessels was performed during the follow-up period. During a mean follow-up period of 18.4 months (range 12-24 months), the average static two-point discrimination score for the injured finger pulp was 4.8 mm (range 3-7 mm), and the Michigan Hand Outcome Questionnaire score was 4.9 mm. The mean range of motion of the distal interphalangeal joint in the injured finger was 69.7°. CONCLUSION: Transplantation of free microvascular flaps from the great toe or the second toe is a useful and reliable technique for finger pulp defect reconstruction. LEVEL OF EVIDENCE V: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Antibiotic penetration into rabbit nucleus pulposus with discitis.

OBJECTIVE: To assess the penetration into nucleus pulposus (NP) of cephazolin and clindamycin in a discitis model. MATERIALS AND METHODS: Twenty New Zealand white rabbits were inoculated with 103 Staphylococcus aureus at lumbar disc space. The rabbits with discitis confirmed by MRI 10 days after inoculation were divided into two groups. One was given cephazolin by intravenous (IV) at 80 mg/kg/day at 1.5 h interval for 5 half-lives; the other was given clindamycin by IV at 30 mg/kg/day at 2.5-h interval for 5 half-lives. Thirty minutes after completion of the last dose, NP and serum were sent to measure antibiotic concentration. RESULTS: Two rabbits died during inoculation. After 10 days, 18 rabbits were confirmed discitis in the inoculated levels. The cephazolin and clindamycin can diffuse throughout the infected, sham-infected and normal NP. The serum concentration of cephazolin and clindamycin was 251.3 ± 40.5 and 21.6 ± 4.71 mg/l, respectively. The cephazolin concentration in infected NP (1.93 ± 0.84 mg/l) was higher than that in sham-infected (1.73 ± 0.61 mg/l) and normal NP (1.68 ± 0.65 mg/l), but the difference showed no statistically significant (P > 0.05). The cephazolin penetration into NP averaged 0.68-0.77 % of serum level. The clindamycin concentration in infected NP (4.32 ± 1.54 mg/l) was higher than that in sham-infected NP (2.63 ± 1.26 mg/l) and normal NP (2.59 ± 1.01 mg/l) (P < 0.05). The penetration into NP averaged 11.9-20 % of serum level. There was no significance difference between sham-infected and normal NP in clindamycin and cephazolin concentration (P > 0.05). CONCLUSIONS: This study demonstrates cephazolin and clindamycin can penetrate the infected and normal NP. The antibiotics charge influences the delivery. Furthermore, infection condition selectively promotes antibiotic distribution within NP.