Two-Part Intertrochanteric Femur Fractures with Bisection of the Lesser Trochanter: An Irreducible Fracture Pattern.

Objective: To introduce the clinical features of and surgical techniques for a rare type of irreducible pertrochanteric femur fracture pattern with bisection of the lesser trochanter. Methods: From January 2017 to December 2019, 357 patients with per/intertrochanteric femur fractures underwent surgery by closed reduction and internal fixation, of whom 12 patients were identified with rare preoperative imaging features, the lesser trochanter was almost equally bisected. The main fracture pathoanatomy of these cases included: The anterior fracture line passed along the intertrochanteric line to the medial lesser trochanter and bisected it into 2 equal parts from mid-level of the lesser trochanteric protrusion. The proximal part of the lesser trochanter connected to the head-neck fragment and attached by the psoas major tendon, while the distal part of the lesser trochanter connected to the femoral shaft and attached by the tendon of the iliac muscle. These fractures were irreducible by a closed maneuver and were reduced with limited assistance by some devices, and short intramedullary nails were used for fixation of these fractures. Results: All patients were followed up for an average of 14.2 ± 2.1 months. Clinical fracture union occurred at an average of 10.8 ± 1.5 weeks, while radiographic union occurred at an average of 12.7 ± 1.2 weeks. No cut out of the helical blade was visible on radiographs. The average Parker-Palmer score was 6.9 ± 1.3 (range, 5-9) at the last follow up, including 8 cases rated as excellent, 2 as good and 2 as fair. Conclusion: Two-part pertrochanteric femur fractures with bisection of the lesser trochanter have an irreducible fracture pattern with cortical locking and soft tissue incarceration. Soft tissue release and short cephalomedullary nail fixation for this fracture pattern provide stable fixation and allow early exercise. This treatment appears to have excellent outcomes in the short and medium terms.

Cyclic hexadepsipeptides from the fermentation of Fusarium sp. DCJ-A and their cytotoxic activities.

Beauvercin H (1), a new cyclic hexadepsipeptide, and two known ones (2 and 3) were isolated from the EtOH extract of the solid culture of Fusarium sp. Their structures were elucidated by spectroscopic analysis, including extensive 1D and 2D NMR techniques, as well as comparison with literature values. Additionally, compounds 1-3 were tested for their cytotoxic activities. The results showed that all isolated compounds exhibited cytotoxic activities against five human cancer cell lines with IC50 values ranging from 1.379 to 13.12 µM.

Low-frequency electroacupuncture improves disordered hepatic energy metabolism in insulin-resistant Zucker diabetic fatty rats via the AMPK/mTORC1/p70S6K signaling pathway.

BACKGROUND AND AIM: Disordered hepatic energy metabolism is found in obese rats with insulin resistance (IR). There are insufficient experimental studies of electroacupuncture (EA) for IR and type 2 diabetes mellitus (T2DM). The aim of this study was to probe the effect of EA on disordered hepatic energy metabolism and the adenosine monophosphate (AMP)-activated protein kinase (AMPK)/mammalian target of rapamycin complex 1 (mTORC1)/ribosomal protein S6 kinase, 70-kDa (p70S6K) signaling pathway. METHODS: Zucker Diabetic Fatty (ZDF) rats were randomly divided into three groups: EA group receiving EA treatment; Pi group receiving pioglitazone gavage; and ZF group remaining untreated (n = 8 per group). Inbred non-insulin-resistant Zucker lean rats formed an (untreated) healthy control group (ZL, n = 8). Fasting plasma glucose (FPG), fasting insulin (FINS), C-peptide, C-reactive protein (CRP) and homeostatic model assessment of insulin resistance (HOMA-IR) indices were measured. Hematoxylin-eosin (H&E) staining was used to investigate the liver morphologically. The mitochondrial structure of hepatocytes was observed by transmission electron microscopy (TEM). Western blotting was adopted to determine protein expression of insulin receptor substrate 1 (IRS-1), mTOR, mTORC1, AMPK, tuberous sclerosis 2 (TSC2) and p70S6K, and their phosphorylation. RT-PCR was used to quantify IRS-1, mTOR, mTORC1, AMPK and p70S6K mRNA levels. RESULTS: Compared with the ZF group, FPG, FINS, C-peptide, CRP and HOMA-IR levels were significantly reduced in the EA group (p < 0.05, p < 0.01). Evaluation of histopathology showed improvement in liver appearances following EA. Phosphorylation levels of AMPK, mTOR and TSC2 decreased, and IRS-1 and p70S6K increased, in hepatocytes of the ZF group, while these negative effects appeared to be alleviated by EA. CONCLUSIONS: EA can effectively ameliorate IR and regulate energy metabolism in the ZDF rat model. AMPK/mTORC1/p70S6K and related molecules may represent a potential mechanism of action underlying these effects.

[Single-segment lumbar microdiscectomy:drainage or not].

OBJECTIVE: To evaluate the safety and feasibility of single-segment lumbar microdiscectomy without drainage. METHODS: The clinical data of 135 patients with single-segment lumbar disc herniation treated by microdiscectomy surgery from January 2018 to August 2019 were retrospectively analyzed. There were 95 males and 40 females, aged from 18 to 40 years old, with a mean of (28.3±5.4) years. They were divided into drainage group (78 cases) and non-drainage group (57 cases) according to whether the drainage tube was placed during operation. The general conditions of patients were recorded such as age, gender, operation segment, body mass index(BMI), symptom duration, follow-up time, operation time, intraoperative blood loss, out-of-bed time, hospital stay, postoperative drainage removal time and drainage volume of drainage group, postoperative body temperature. VAS of incisional pain in supine resting state on the 1 and 3 days after operation, the VAS of low back pain and lower extremity radiating pain during ground exercise before operation, 3 days, 1 month and 3 months after operation were compared. Oswestry Disability Index (ODI) was collected before operation, 1 month and 3 months after operation. The ratio of complications was calculated such as symptomatic incision hematoma, poor incision healing, incision infection, exacerbation and progressive aggravation of neurological dysfunction, and unplanned secondary surgery. RESULTS: There were no significant differences in age, gender, operation segment, BMI, symptom duration, follow-up time, operation time, intraoperative blood loss, and postoperative body temperature between two groups. The average hospital stay and out-of-bed time in non-drainage group were shorter than in drainage group(P=0.0000). VAS of incision pain in non-drainage group was lower than that in control group at 1 and 3 days after surgery (P<0.05). Postoperative low back pain VAS and ODI of all patients were significantly reduced compared with those before surgery. No symptomatic hematoma occurred in two groups. Postoperative neurological dysfunction immediately aggravated each one patient in two groups, and no progressive aggravation of neurological function was found in two groups. Incision infection occurred in one case in each of the two groups, and both were cured by drug treatment; poor incision healing occurred in one case in each of the two groups, and both were healed after repeated dressing changes. There was one case of unplanned second operation in drainage group, the patient received a second operation due to disc protrusion recurrence within 1 month. CONCLUSION: Single-segment lumbar microdiscectomy without drainage can shorten the average hospital stay and promote early exercise out of bed, and reduce the trauma and stress reaction of drainage. No drainage may be an option for patients with enhanced recovery after lumbar microdiscectomy.

Repair of symptomatic bilateral L5 spondylolysis with autogenous iliac crest graft and temporary intersegmental pedicle screw fixation in youth.

BACKGROUND: When symptomatic spondylolysis fail to respond to nonoperative treatment, surgical management may be required. A number of techniques have been described for repair by intrasegmental fixation with good results; however, there are still some problems. We reported a repair technique with temporary intersegmental pedicle screw fixation and autogenous iliac crest graft. The aim of present study is to assess the clinical outcomes of L5 symptomatic spondylolysis with this technique. METHODS: A retrospective analysis of 128 patients with L5 spondylolysis treated with this method was performed. According to CT scan, the spondylolysis were classified into 3 categories: line, intermediate, and sclerosis type. The diagnostic block test of L5 bilateral pars defect was done in all patients preoperatively. The sagittal and axial CT images were used to determine the bone union. The healing time, complications, number of spina bifida occulta, Japanese Orthopedic Association (JOA) score, and VAS for back pain were recorded. After fixation removal, the rate of ROM preservation at L5S1 was calculated. RESULTS: There were 97 patients (194 pars) followed with mean follow-up of 23 months (range, 12-36 months). The union rate of pars was 82.0% at 12 months and 94.3% at 24 months postoperatively. Low back pain VAS significantly (P < 0.05) improved from preoperative mean value of 7.2 to 1.3 at the final follow-up postoperatively (P < 0.05). JOA score increased significantly postoperatively (P < 0.05) with average improvement rate of 79.3%. The rates of L5S1 ROM preservation were 79.8% and 64.0% after fixation removal at 1 and 2 years postoperatively. There were 3 patients of delayed incision healing without other complications. CONCLUSIONS: Although sacrificing L5S1 segment motion temporarily, more stability was obtained with intersegmental fixation. This technique is reliable for spondylolysis repair which has satisfactory symptom relief, high healing rate, low incidence of complications, and preserve a large part of ROM for fixed segment.

[Adsorption Mechanism of Cadmium by Superparamagnetic Nano-Fe3 O4@SiO2 Functionalized Materials].

The treatment of cadmium-containing wastewater is of great significance for the emission control of the heavy metal cadmium. Here, a superparamagnetic nano-Fe3O4@SiO2 functionalized material (MFS) was prepared via a co-precipitation method, and the adsorption thermodynamic and kinetic characteristics of Cd2+ were studied by isothermal adsorption tests and kinetic experiments. The adsorption process and mechanism of MFS with respect to Cd2+ were also studied using BET, XRD, and SEM. The Langmuir equation well described the isothermal adsorption characteristics of MFS, and the maximum adsorption capacity was 69.49 mg·g-1. The standard free energy (ΔG), enthalpy (ΔH), and entropy changes (ΔS) showed that the adsorption reaction was a spontaneous, endothermic, and entropic process. The optimal initial pH of the adsorption reaction was 7. The four interfering ions (Mg2+, SO42-, Ca2+, and NO3-) in the solution had a certain inhibitory effect on the adsorption reaction. The pseudo-second-order kinetic model showed that the adsorption process of Cd2+ was divided into two stages, namely a rapid external diffusion stage and a slow internal diffusion stage. The removal rate of Cd2+ was still>73% after using the MFS three times. The BET, XRD, FTIR, and VSM analyses showed that SiO2 was successfully modified on the Fe3O4 surface. MFS is mainly spherical in structure with an average particle size of 38.7 nm and has a saturated magnetic intensity of 85.38 emu·g-1. The XRD, EDS, and XPS analyses revealed that Cd2+ was successfully adsorbed by the material, and the main mechanism was the coordination reaction between Cd2+ and -OH on the surface of the material.

[Effects of Superparamagnetic Nanomaterials on Soil Microorganisms and Enzymes in Cadmium-Contaminated Paddy Fields].

Using Fe3O4 and hydroxyapatite as raw materials, superparamagnetic nanometer-sized Fe3O4-phosphate functionalized materials (MFH) were prepared. Soil was subsequently magnetically repaired by adding MFH to cadmium-contaminated paddy field soil. Two kinds of rice with high (Yuzhenxiang) and low (Xiangwanxian-13) cadmium enrichment were selected for conduct pot experiments to study the effect of MFH magnetic separation on soil microorganisms and enzymes, and explore the possibility of application in the remediation of cadmium-polluted farmland. The results showed that MFH application improved the soil remediation effect, with significantly reduced total Cd (38.9%) and available Cd (27.3%) contents. In addition, the Cd content of the two kinds of rice grain was significantly reduced. After MFH magnetic separation, soil microbial community diversity and richness were decreased during the jointing, heading, and maturing stages of the two rice varieties. Treatment of cultivated Yuzhenxiang rice with high concentrations of Cd significantly increased the abundance of dominant Firmicute bacteria in the rice field during the jointing and heading stages. With the use of MFH in the magnetic separation, urease, catalase, and soil peroxidase activity were improved during the jointing, heading, and maturing stages of the two rice soils. The POD enzyme activity in the soil planted with Yuzhenxiang was slightly higher than that planted with Xiangwanxian-13, while urease activity showed the opposite trend.

Knockdown of Arginyl-tRNA Synthetase Attenuates Ischemia-Induced Cerebral Cortex Injury in Rats After Middle Cerebral Artery Occlusion.

Some researchers have previously shown that RNAi knockdown of arginyl-tRNA synthetase (ArgRS) before or after a hypoxic injury can rescue animals from death, based on the model organism, C. elegans. However, there has been no study on the application of arginyl-tRNA synthetase knockdown in treating mammalian ischemic stroke, and its potential mechanism and effect on ischemic brain damage are still unknown. Here, we focused on the Rars gene, which encodes an arginyl-tRNA synthetase, and examined the effects of Rars knockdown in a permanent middle cerebral artery occlusion model in rats. To achieve this aim, adult male Sprague-Dawley (SD) rats were given right cerebral cortex injections of short hairpin RNA (shRNA) adenovirus (AV) particles to knock down arginyl-tRNA synthetase, and a non-targeting control (NTC) vector or phosphate-buffered solution served as the controls. After 4 days, the rats were exposed to permanent middle cerebral artery occlusion (pMCAO). Then, the right cerebral cortex level of arginyl-tRNA synthetase was examined, and the effects of the Rars knockdown were evaluated by differences in infarction volume, oxidative stress, blood-brain barrier, mitochondrial function, and glucose metabolism at 1 day and 3 days after MCAO. The injection of shRNA adenovirus particles successfully suppressed the expression of arginyl-tRNA synthetase in the cerebral cortex. We observed an improvement in oxidative stress, mitochondrial function, and glucose utilization and a reduction in brain edema compared with the non-targeting control rats with suppressed expression of arginyl-tRNA synthetase mRNA in the ipsilateral ischemic cortex of the brain. Our findings indicate that knockdown of arginyl-tRNA synthetase in the cerebral cortex exerted neuroprotective effects, which were achieved not only by the improvement of oxidative stress and glucose utilization but also by the maintenance of mitochondrial morphological integrity and the preservation of mitochondrial function. Knockdown of ArgRS administration could be a promising approach to protect ischemic stroke.

Accurate identification of myocardial viability after myocardial infarction with novel manganese chelate-based MR imaging.

We developed a novel manganese (Mn2+ ) chelate for magnetic resonance imaging (MRI) assessment of myocardial viability in acute and chronic myocardial infarct (MI) models, and compared it with Gadolinium-based delay enhancement MRI (Gd3+ -DEMRI) and histology. MI was induced in 14 rabbits by permanent occlusion of the left circumflex coronary artery. Gd3+ -DEMRI and Mn2+ chelate-based delayed enhancement MRI (Mn2+ chelate-DEMRI) were performed at 7 days (acute MI, n = 8) or 8 weeks (chronic MI, n = 6) after surgery with sequential injection of 0.15 mmol/kg Gd3+ and Mn2+ chelate. The biodistribution of Mn2+ in tissues and blood was measured at 1.5 and 24 h. Blood pressure, heart rate (HR), left ventricular (LV) function, and infarct fraction (IF) were analyzed, and IF was compared with the histology. The Mn2+ chelate group maintained a stable hemodynamic status during experiment. For acute and chronic MI, all rabbits survived without significant differences in HR or LV function before and after injection of Mn2+ chelate or Gd3+ (p > 0.05). Mn2+ chelate mainly accumulated in the kidney, liver, spleen, and heart at 1.5 h, with low tissue uptake and urine residue at 24 h after injection. In the acute MI group, there was no significant difference in IF between Mn2+ chelate-DEMRI and histology (22.92 ± 2.21% vs. 21.79 ± 2.25%, respectively, p = 0.87), while Gd3+ -DEMRI overestimated IF, as compared with histology (24.54 ± 1.73%, p = 0.04). In the chronic MI group, there was no significant difference in IF between the Mn2+ chelate-DEMRI, Gd3+ -DEMRI, and histology (29.50 ± 11.39%, 29.95 ± 9.40%, and 29.00 ± 10.44%, respectively, p > 0.05), and all three were well correlated (r = 0.92-0.96, p < 0.01). We conclude that the use of Mn2+ chelate-DEMRI is reliable for MI visualization and identifies acute MI more accurately than Gd3+ -DEMRI.

Graphene oxide and carbon dots as broad-spectrum antimicrobial agents - a minireview.

Due to the increasing global population, growing contamination of water and air, and wide spread of infectious diseases, antibiotics are extensively used as a major antibacterial drug. However, many microbes have developed resistance to antibiotics through mutation over time. As an alternative to antibiotics, antimicrobial nanomaterials have attracted great attention due to their advantageous properties and unique mechanisms of action toward microbes. They inhibit bacterial growth and destroy cells through complex mechanisms, making it difficult for bacteria to develop drug resistance, though some health concerns related to biocompatibility remain for practical applications. Among various antibacterial nanomaterials, carbon-based materials, especially graphene oxide (GO) and carbon dots (C-Dots), are promising candidates due to the ease of production and functionalization, high dispersibility in aqueous media, and promising biocompatibility. The antibacterial properties of these nanomaterials can be easily adjusted by surface modification. They are promising materials for future applications against multidrug-resistant bacteria based on their strong capacity in disruption of microbial membranes. Though many studies have reported excellent antibacterial activity of carbon nanomaterials, their impact on the environment and living organisms is of concern due to the accumulatory and cytotoxic effects. In this review, we discuss antimicrobial applications of the functional carbon nanomaterials (GO and C-Dots), their antibacterial mechanisms, factors affecting antibacterial activity, and concerns regarding cytotoxicity.

Estrogen receptor ß upregulated by lncRNA-H19 to promote cancer stem-like properties in papillary thyroid carcinoma.

Estrogen receptor ß (ERß) plays critical roles in thyroid cancer progression. However, its role in thyroid cancer stem cell maintenance remains elusive. Here, we report that ERß is overexpressed in papillary thyroid cancer stem cells (PTCSCs), whereas ablation of ERß decreases stemness-related factors expression, diminishes ALDH+ cell populations, and suppresses sphere formation ability and tumor growth. Screening estrogen-responsive lncRNAs in PTC spheroid cells, we find that lncRNA-H19 is highly expressed in PTCSCs and PTC tissue specimens, which is correlated with poor overall survival. Mechanistically, estradiol (E2) significantly promotes H19 transcription via ERß and elevates H19 expression. Silencing of H19 inhibits E2-induced sphere formation ability. Furthermore, H19 acting as a competitive endogenous RNA sequesters miRNA-3126-5p to reciprocally release ERß expression. ERß depletion reverses H19-induced stem-like properties upon E2 treatment. Appropriately, ERß is upregulated in PTC tissue specimens. Notably, aspirin attenuates E2-induced cancer stem-like traits through decreasing both H19 and ERß expression. Collectively, our findings reveal that ERß-H19 positive feedback loop has a compelling role in PTCSC maintenance under E2 treatment and provides a potential therapeutic targeting strategy for PTC.

[Comparison of clinical effects of total artificial hip replacement and cannulated screw fixation for the treatment of displaced femoral neck fractures in elderly patients].

OBJECTIVE: To compare of clinical effects of different surgical methods in the treatment of elderly femoral neck fractures. METHODS: From January 2013 to June 2016, 144 elderly patients with femoral neck were treated and divided into artificial hip replacement group and cannulated screw fixation group according to the surgical methods. In the total hip arthroplasty group, there were 89 cases, 28 males and 61 females, with an average age of(84.10±3.10) years old;Hollow nail fixation group 55 cases, 20 males and 35 females, with an average age of (86.80±2.88) years. Preoperative patients data, postoperative complications, mortality and postoperative Harris hip score were compared between the two groups. RESULTS: A total of 144 cases were followed up for 12 to 36 months with an average of 18 months. There was no significant difference between two groups in gender, fracture side, preoperative complications, osteoporosis, ASA score, injury to surgery interval, the number of patients admitted to ICU and perioperative death. However, the patients in hollow screw fixation group was older than the joint replacement group(t=5.311, P<0.05);The degree of preoperative fracture displacement in the joint replacement group was higher than that in the hollow nail fixation group(χ²=6.894, P=0.009<0.05);Hollow nail fixation group in operation time, hospital stay, intraoperative blood loss, perioperative blood transfusion was significantly better than the number of joint replacement group(P<0.05);The Harris score of the joint replacement group was higher than that of the hollow screw fixation group(P<0.05). CONCLUSIONS: For elderly femoral neck patients, if there is a significant shift in the fracture (Garden III, IV), the preferred treatment is hip replacement. Postoperative complications are relatively small, satisfactory joint function recovery. If the fracture displacement is not obvious (Garden type I, II) or patients with more medical diseases, poor physical condition, poor surgical tolerance, postoperative life expectancy is not high, the first choice is closed reduction and cannulated screw fixation.

Sphingosine 1-Phosphate Postconditioning Protects Against Myocardial Ischemia/reperfusion Injury in Rats via Mitochondrial Signaling and Akt-Gsk3ß Phosphorylation.

BACKGROUND AND AIMS: Although preconditioning of sphingosine 1-phosphate (S1P) has been shown to protect myocytes from hypoxia reoxgenation injury in vitro, the role of S1P postconditioning on myocardial ischemia reperfusion injury (MIRI) in vivo and its related mechanism are unknown. The aim of this study was to investigate the protective role of sphingosine 1-phosphate (S1P) postconditioning in MIRI via its effects on mitochondrial signaling and Akt/Gsk3ß phosphorylation. METHODS: Rats were subjected to MIRI, consisting of 30 min of ischemia followed by 120 min of reperfusion, with S1P administered at the beginning of the reperfusion. Myocardial infarct size and apoptotic index were measured by triphenyltetrazolium (TTC) and terminal deoxynucleotide transferase dUTP nick-end labeling (TUNEL) assays, respectively. Akt and Gsk3ß phosphorylation, caspase-3 cleavage, and cytochrome c translocation were assessed by western blot. Mitochondrial permeability transition pore (MPTP) opening and mitochondrial membrane potential (MMP, ΔΨ) were also examined to determine overall mitochondrial function. RESULTS: S1P postconditioning significantly decreased myocardial infarct size and apoptosis, as well as enhanced Akt and Gsk3ß phosphorylation, attenuated caspase-3 cleavage and cytosolic cytochrome c translocation, and inhibited MPTP opening, which subsequently preserved Δψ. Electron microscopy also confirmed that S1P helped maintain myocardial mitochondria integrity. Moreover, the protective effects of S1P treatment were blocked by cotreatment with a PI3K inhibitor, LY294002. CONCLUSIONS: These results suggest that S1P postconditioning protects against MIRI by regulating mitochondrial signaling and Akt/Gsk3ß phosphorylation.

A nine-coordinated bismuth(III) complex derived from pentadentate 2,6-diacetylpyridine bis((4)N-methylthiosemicarbazone): crystal structure and both in vitro and in vivo biological evaluation.

Up to now, bismuth(III) complexes with thiosemicarbazones have been comparatively rare. Few in vivo biological studies have been carried out in comparison to the plentiful in vitro data. Here, an interesting nine-coordinated bismuth(III) complex, [Bi(H2L)(NO3)2]NO3 [1; H2L = 2,6-diacetylpyridine bis((4)N-methylthiosemicarbazone)], has been synthesized and structurally characterized. The analytical data reveal the formation of 1:1 (metal/ligand) stoichiometry. In vitro biological studies have indicated that the bismuth complex 1 has shown much higher antibacterial and anticancer activities than its parent ligand, especially with MIC = 10.66 µM against Bacillus cereus and Salmonella typhimurium and IC50 = 26.8 µM against K562 leukemia cells, respectively. More importantly, it also evidently inhibits H22 xenograft tumor growth on tumor-bearing mice (10 mg/kg; inhibitory rate = 61.6%). These results indicate that coordination to bismuth(III) might be an interesting strategy in the discovery of new anticancer drug candidates.

[MR imaging of polyethylenimine-superparamagnetic iron oxide nanoparticle labeled bone marrow mesenchymal stem cells in vitro].

OBJECTIVE: To explore the optimal concentration of polyethylenimine-superparamagnetic iron oxide (PEI2k-SPIO) particles for labeling bone marrow mesenchymal stem cells (BMSCs) in vitro, then to demonstrate the imaging characteristics of the cells by 7.0-T MR scanner. The lowest cell quantity and the optimal cell quantity detected on MR was observed. METHODS: Cells at 2nd passage were inoculated into the 6-hole plate with cover glass. The different concentrations of PEI2k-SPIO (5 microg/mL, 7 microg/mL, 10 microg/mL, 15 microg/mL, 20 microg/mL) were added into different holes, respectively. After labeled with different concentrations of PEI2k-SPIO, the Prussian blue stain was used for determining the labeling efficiency. MTT growth curves were used to identify the activity of BMSCs and to determine the optimal threshold of SPIO nanocomposite particles labeled the stem cells at different PEI2k-SPIO concentrations (7, 10, 15, 20 microg Fe/mL medium). To definite the lowest cells quantity and the optimal observable cells quantity on MR imaging, 1 x 10(6), 1 x 10(5), 1 x 10(4) and 1 x 10(3) cells labeled with optimal threshold of PEI2k-SPIO and 1 x 10(6) cells unlabeled suspended in 0.2 mL agarose (10 g/L), respectively undergone MR scan. RESULTS: MTT growth curves showed the optimal threshold of PEI2k-SPIO labeled BMSCs was 7 microg/mL, which indicates has no adverse effects on the growth of stem cells. At the opimal concentration (7 microg Fe/mL), the lowest observable cell quantity of PEI2k-SPIO-labeled cells for MRI was 1 x 10(4), and the optimal observable cell quantity was 1 x 10(6). CONCLUSION: At the opimal concentration, adverse effect to stem cell activities had not be detected when were labeled with PEI2k-SPIO and the clearly image of MRI of labeled BMSCs could be obtained.

Synthesis, crystal structures, in vitro biological evaluation of zinc(II) and bismuth(III) complexes of 2-acetylpyrazine N(4)-phenylthiosemicarbazone.

Two metal complexes formulated as [Zn(L)(2)](2)·H(2)O (1) and [Bi(L)(NO(3))(2)(CH(3)OH)] (2), where HL=2-acetylpyrazine N(4)-phenylthiosemicarbazone, have been synthesized and characterized by elemental analysis, IR, MS, NMR and single-crystal X-ray diffraction studies. Biological studies, carried out in vitro against selected bacteria and the K562 leukemia cell lines, respectively, have shown that the free ligand and its two complexes may be endowed with important biological properties, especially HL with MIC=3.90 µg/mL against Pseudomonas aeruginosa, the zinc(II) complex 1 with IC(50)=1.0 µM against K562 leukemia cell lines, respectively. The compounds HL and 1 may exert their cytotoxicity activity via induced loss of mitochondria membrane potential (MMP).

Synthesis, crystal structures, and biological evaluation of Cu(II) and Zn(II) complexes of 2-benzoylpyridine Schiff bases derived from S-methyl- and S-phenyldithiocarbazates.

Two NNS tridentate Schiff base ligands of 2-benzoylpyridine S-methyldithiocarbazate (HL(1)) and 2-benzoylpyridine S-phenyldithiocarbazate (HL(2)) and their transition metal complexes [Cu(2)(L(1))(2)(CH(3)COO)](ClO(4)) (1), [Zn(2)(L(1))(2)(ClO(4))(2)] (2), [Zn(L(2))(2)](3) have been prepared and characterized by elemental analysis, IR, MS, NMR and single-crystal X-ray diffraction studies. In the solid state, each of two Schiff bases remains in its thione tautomeric form with the thione sulfur atom trans to the azomethine nitrogen atom. Under similar prepared conditions, three new complexes showed distinctly different coordination modes depending on their coordinating preferences. Each copper atom in S-bridged dinuclear complex [Cu(2)(L(1))(2)(CH(3)COO)](ClO(4)) (1) is surrounded by five donor atoms in a square-pyramidal fashion (4+1). [Zn(2)(L(1))(2)(ClO(4))(2)] (2) is a dimer in which each zinc atom adopts a seven-coordinate distorted pentagonal bipyramidal geometry, while mononuclear [Zn(L(2))(2)] (3) has octahedral coordination geometry. Biological studies, carried out in vitro against selected bacteria, fungi, and K562 leukaemia cell line, respectively, have shown that different substituted groups attached at the dithiocarbazate moieties and metals showed distinctive differences in the biological property. Zinc(II) complexes 2 and 3 could distinguish K562 leukaemia cell line from normal hepatocyte QSG7701 cell line. Effect of the title compounds on Mitochondria membrane potential (MMP) and PI-associated fluorescence intensity in K562 leukaemia cell line are also studied. The title compounds may exert their cytotoxicity activity via induced loss of MMP.

Synthesis, crystal structures, and biological evaluation of manganese(II) and nickel(II) complexes of 4-cyclohexyl-1-(1-(pyrazin-2-yl)ethylidene)thiosemicarbazide.

4-Cyclohexyl-1-(1-(pyrazin-2-yl)ethylidene)thiosemicarbazide (HL) and its transition metal complexes formulated as [Mn(L)(2)] (1) and [Ni(L)(2)] (2) have been prepared in 55-75% yield and characterized by elemental analysis, IR, MS, NMR and single-crystal X-ray diffraction studies. Biological activities of the synthesized compounds have been evaluated against selected Gram positive bacteria Bacillus subtilis, Gram negative bacteria Pseudomonas aeruginosa and the K562 leukemia cell line, respectively. The cytotoxicity data suggest that these compounds may be endowed with important biological properties, especially the nickel complex 2 with MIC = 31.2 µg/mL and IC(50) = 0.53 µM, respectively. Effect of the free ligand and its two complexes on Mitochondria membrane potential (MMP) and PI-associated fluorescence intensity as well as their effect on cell apoptosis in K562 leukemia cell line was also studied. The tested compounds may exert their cytotoxicity activity via induced loss of MMP.

Tumor-initiating cells and tumor vascularization.

Tumor-initiating cells (TICs) with stem-like cell properties initiate and sustain progressive growth, resulting in a heterogeneous tumor mass. The survival and growth of tumors rely on the development of a vasculature to provide nutrients and oxygen. Crosstalk between TICs and vascularization may be one of the central players in the initiation, long-term maintenance, and progression of tumors. This review surveys current evidence concerning the crosstalk that occurs in tumor/stromal interactions, including genetic change, vascular niche, hypoxia, and dormancy of tumors. A better understanding of this crosstalk might help provide the basis for developing more effective therapeutic drug targets.

[Posterior longitudinal strip osteotomy of proximal femur in revision total hip arthroplasty].

OBJECTIVE: To evaluate the treatment and effect of a technique using single femoral posterior longitudinal strip osteotomy in revision total hip arthroplasties. METHODS: Between September 2005 and December 2009, 35 hips of 35 patients underwent a revision total hip arthroplasties (THA) in conjunction with extraction of femoral components. Among them, 23 cases were with uncemented, and 12 cases were with cemented femoral components. Those cases being followed up were chosen by two standards described as follows: one was the examination of preoperative radiographs, which showed that there was difficult in the extraction of the femoral components; Another followed was the trying with routine procedure to remove the stem. If these were unsuccessful, a single longitudinal strip osteotomy was performed, whose length was about 11 - 14 cm, and width was about 1 cm. Then the femoral component was disimpact. The osteotomy was fixed with wires or cables. If there was cortical deficiency or insufficient cancellous bone, grafting was performed. A cementless composite revision prosthesis of the Lima-Lto with a tapered modular distal fixation stem was used. All the patients were evaluated with preoperative and postoperative Harris score, the length of limb and radiographs. RESULTS: All cases were followed up with 5 to 55 months, average 15 months. Compared with preoperative, the average Harris score increased from 30 (range, 19 - 40 points) to 85 points (range, 80 - 92 points). All pains of hip joint were alleviated from the mean 12 points (range, 10 - 20 points) before the operation to 40 points (range, 30 - 44 points) after the operation. All the femoral osteotomy and bone grafting were healing ultimately. And on average, the healing began in 20 weeks (range, 10 - 32 weeks). All the cases remain the same length of lower limbs. There was no hip joint dislocation, loosening or infection. CONCLUSIONS: The femoral posterior longitudinal strip osteotomy facilitates the exposure and extraction of the femoral stem, the clear up of medullary cavity and then the femoral reconstruction in revision total hip arthroplasties. It has satisfactory short-term radiographic evaluation and clinical effect as a simple, effective and reliable technique.