The protective role of chicken cathelicidin-1 against Streptococcus suis serotype 2 in vitro and in vivo.

Streptococcus suis serotype 2 (SS2) is an important zoonotic pathogen with the characteristics of high mortality and morbidity, which brings great challenges to prevent and control epidemic disease in the swine industry. Cathelicidins (CATH) are antimicrobial peptides with antimicrobial and immunomodulatory activities. In this study, bactericidal and anti-inflammatory effects of chicken cathelicidin-1 (CATH-1) were investigated in vitro and in vivo against SS2 infection. The results show that CATH-1 exhibited a better bactericidal effect compared to other species' cathelicidins including chickens (CATH-2, -3, and -B1), mice (CRAMP) and pigs (PMAP-36 and PR-39), which rapidly killed bacteria in 20 min by a time-killing curve assay. Furthermore, CATH-1 destroyed the bacterial morphology and affected bacterial ultrastructure as observed under electron microscopy. Moreover, CATH-1 antibacterial activity in vivo shows that CATH-1 increased survival rate of SS2-infected mice by 60% and significantly reduced the bacterial load in the lungs, liver, spleen, blood, and peritoneal lavage as well as the release of SS2-induced inflammatory cytokines including IL-1α, IL-1ß, IL-12, and IL-18. Importantly, CATH-1 did not show severe histopathological changes in mice. Further studies on the mechanism of anti-inflammatory activity show that CATH-1 not only reduced the inflammatory response through direct neutralization, but also by regulating the TLR2/4/NF-κB/ERK pathway. This study provides a scientific basis for the research and development of antimicrobial peptides as new antimicrobial agents.

Supplementing conjugated linoleic acid in breeder hens diet increased conjugated linoleic acid incorporation in liver and alters hepatic lipid metabolism in chick offspring.

This experiment was designed to investigate the effect of supplementing conjugated linoleic acid (CLA) in breeder hens diet on development and hepatic lipid metabolism of chick offspring. Hy-Line Brown breeder hens were allocated into two groups, supplemented with 0 (control (CT)) or 0·5 % CLA for 8 weeks. Offspring chicks were grouped according to the mother generation and fed for 7 d. CLA treatment had no significant influence on development, egg quality and fertility of breeder hens but darkened the egg yolks in shade and increased yolk sac mass compared with the CT group. Addition of CLA resulted in increased body mass and liver mass and decreased deposition of subcutaneous adipose tissue in chick offspring. The serum TAG and total cholesterol levels of chick offspring were decreased in CLA group. CLA treatment increased the incorporation of both CLA isomers (c9t11 and t10c12) in the liver of chick offspring, accompanied by the decreased hepatic TAG levels, related to the significant reduction of fatty acid synthase (FAS) and acetyl-CoA carboxylase (ACC) enzyme activities and the increased carnitine palmitoyltransferase-1 (CPT1) enzyme activity. Meanwhile, CLA treatment reduced the mRNA expression of genes related to fatty acid biosynthesis (FAS, ACC and sterol regulatory element-binding protein-1c) and induced the expression of genes related to ß-oxidative (CPT1, AMP-activated protein kinase and PPARα) in chick offspring liver. In summary, the addition of CLA in breeder hens diet significantly increased the incorporation of CLA in the liver of chick offspring, which further regulate hepatic lipid metabolism.

Synthetic Landau Levels and Spinor Vortex Matter on a Haldane Spherical Surface with a Magnetic Monopole.

We present a flexible scheme to realize exact flat Landau levels on curved spherical geometry in a system of spinful cold atoms. This is achieved by applying the Floquet engineering of a magnetic quadrupole field to create a synthetic monopole field in real space. The system can be exactly mapped to the electron-monopole system on a sphere, thus realizing Haldane's spherical geometry for fractional quantum Hall physics. This method works for either bosons or fermions. We investigate the ground-state vortex pattern for an s-wave interacting atomic condensate by mapping this system to the classical Thompson's problem. The distortion and stability of the vortex pattern are further studied in the presence of dipolar interaction. Our scheme is compatible with the current experimental setup, and may serve as a promising route of investigating quantum Hall physics and exotic spinor vortex matter on curved space.

Cavity-Assisted Single-Mode and Two-Mode Spin-Squeezed States via Phase-Locked Atom-Photon Coupling.

We propose a scheme to realize the two-axis countertwisting spin-squeezing Hamiltonian inside an optical cavity with the aid of phase-locked atom-photon coupling. By careful analysis and extensive simulation, we demonstrate that our scheme is robust against dissipation caused by cavity loss and atomic spontaneous emission, and it can achieve significantly higher squeezing than one-axis twisting. We further show how our idea can be extended to generate two-mode spin-squeezed states in two coupled cavities. Because of its easy implementation and high tunability, our scheme is experimentally realizable with current technologies.

Dynamically Manipulating Topological Physics and Edge Modes in a Single Degenerate Optical Cavity.

We propose a scheme to simulate topological physics within a single degenerate cavity, whose modes are mapped to lattice sites. A crucial ingredient of the scheme is to construct a sharp boundary so that the open boundary condition can be implemented for this effective lattice system. In doing so, the topological properties of the system can manifest themselves on the edge states, which can be probed from the spectrum of an output cavity field. We demonstrate this with two examples: a static Su-Schrieffer-Heeger chain and a periodically driven Floquet topological insulator. Our work opens up new avenues to explore exotic photonic topological phases inside a single optical cavity.

Differential wetting characterization of hair fibers.

Surface wetting is one of the key properties of human hair used to indicate the extent of chemical/mechanical damage and the outcome of conditioning treatment. Characterization of hair wetting property is a challenging task due to the non-homogeneous nature of hair fibers and the requirement for sensitive equipment. Motivated by these considerations, we developed a new methodology, termed a differential wetting characterization (DWC), which would allow rapid and reliable characterization of the wetting property of hair fibers. This method is based on observation of a number of droplets suspended on a pair of parallel fibers stretched in a horizontal plane. The wetting behavior of the fibers can be deduced from the shape assumed by the droplets. When the wetting properties of the two hair fibers are identical, the droplets suspended between the fibers assume a symmetric configuration. In contrast, on the fibers with dissimilar wetting characteristics, the droplets will assume a skewed configuration towards a more hydrophilic fiber. This makes it possible to differentiate the hydrophobicities of the tested fibers. In this paper it is demonstrated that the proposed DWC method is capable of differentiating the changes in wetting property of hair surfaces in response to either chemical or physical treatment. Results of the paper indicate that the DWC method is applicable for broad wetting differentiation of various fibers.

Green Synthesis of Soy Protein Nanocomposites: Effects of Cross-Linking and Clay Nanoparticles on the Mechanical Performance.

A green synthesis scheme was adopted for preparation of soy-protein-based clay nanocomposites, in which soy protein isolates (SPIs) were utilized as the biodegradable resin and clay nanoparticles (CNPs) were used as the nanoreinforcing phase. Cross-linking of the SPIs was realized through an aqueous reaction scheme with oxidized sugars (e.g., glucose and sucrose as the typical constituents of soy flours) as the cross-linkers. Toughening effects of the cross-linkers, process parameters, and CNPs on the mechanical properties (e.g., tensile strength, stiffness, strain at break, and toughness) of the resulting SPI-based clay nanocomposites were examined by micromechanical tensile testing. The cross-linking and toughening mechanisms of the SPI-based nanocomposites were evaluated by Fourier transform infrared spectroscopy, sol-gel and color characterization, scanning differential calorimetry, and transmission electron microscopy. Thermal stability of the cross-linked SPIs was evaluated by thermogravimetric analysis. Experimental results show that cross-linking can noticeably improve both the tensile strength and tensile modulus of the resulting SPI films, and a small quantity of CNPs can obviously alter the mechanical properties of the resulting clay nanocomposite films. The present study indicates that defatted soy flours can be directly utilized for developing low-cost, SPI-based nanocomposites without the need for external plasticizers, and the entire synthesis is completely green without involvement of any petroleum-based organic solvents, polymers, and metallic catalysts. Such biodegradable SPI-based green nanocomposites have the potential to substitute fossil-based plastics and polymer composites for use in various industrial products and house utilities.

[Effect of sodium para-aminosalicylic on concentrations of amino acid neurotransmitters in basal ganglia of manganese-exposed rats].

OBJECTIVE: To probe the effect of sodium para-aminosalicylate (PAS-Na) on concentration of amino acid neurotransmitters including glutamate (Glu), glutamine (Gln), glycine (Gly) and gamma-aminobutyric acid (GABA) in basal ganglia of subacute manganese (Mn)-exposed rats. METHODS: Forty Sprague-Dawley male rats were randomly divided into the control, Mn-exposed, low dose PAS-Na (L-PAS) and high dose PAS-Na (H-PAS) groups. Rats in experiment groups received daily intraperitoneally injections of manganese chloride (MnCl2 · 4H2O, 15 mg/kg), while rats in control group received daily intraperitoneally injections of normal saline (NS), all at 5 days/week for 4 weeks. Then the rats in PAS groups followed by a daily subcutaneously dose of PAS-Na (100 and 200 mg/kg as the L-PAS and H-PAS groups, respectively) for another 3 and 6 weeks; while the rats in Mn-exposed and control group received NS. The concentrations of Glu, Gln, Gly and GABA in basal ganglia of rat was detected by the high performance liquid chromatography fluorescence detection technique. RESULTS: After treating with PAS-Na for 3 weeks, the concentration of Gly in the Mn-exposed rats decreased to (0.165 ± 0.022) µmol/L (control = (0.271 ± 0.074) µmol/L, Mn vs control, t = 4.65, P < 0.05). After the further 6-week therapy with PAS-Na, the concentrations of Glu, Gln, Gly in the Mn-exposed rats were lower than those of the control rats ((0.942 ± 0.121), (0.377 ± 0.070), (0.142 ± 0.048), (1.590 ± 0.302), (0.563 ± 0.040), (0.247 ± 0.084) µmol/L; t = 7.72, 5.85, 4.30, P < 0.05); and also lower than in L-PAS and H-PAS groups, whose concentrations were separately (1.268 ± 0.124), (1.465 ± 0.196), (0.497 ± 0.050), (0.514 ± 0.103), (0.219 ± 0.034) µmol/L (L-PAS Glu and Gln vs Mn, t = 3.87, 3.77, P < 0.05; H-PAS Glu, Gln and Gly vs Mn, t = 6.78, 4.70, 3.42, P < 0.05). CONCLUSION: The toxic effect of manganese on Glu, Gln and Gly in basal ganglia of Mn-exposed rats is obvious, especially appears earlier on Gly. The toxic effect still continues to develop when relieved from the exposure. PAS-Na may play an antagonism role in toxic effect of manganese on concentration of Glu, Gln and Gly in basal ganglia of Mn-exposed rats.

Circumferential wrinkling of polymer nanofibers.

Surface wrinkles are commonly observed in soft polymer nanofibers produced in electrospinning. This paper studies the conditions of circumferential wrinkling in polymer nanofibers under axial stretching. A nonlinear continuum mechanics model is formulated to take into account the combined effects of surface energy and nonlinear elasticity of the nanofibers on wrinkling initiation, in which the soft nanofibers are treated as incompressible, isotropically hyperelastic neo-Hookean solid. The critical condition to trigger circumferential wrinkling is determined and its dependencies upon the surface energy, mechanical properties, and geometries of the nanofibers are examined. In the limiting case of spontaneous circumferential wrinkling, the theoretical minimum radius of soft nanofibers producible in electrospinning is determined, which is related closely to the intrinsic length l_{0}=γ/E of the polymer (γ: the surface energy; E: a measure of the elastic modulus), and compared with that of spontaneous longitudinal wrinkling in polymer nanofibers. The present study provides a rational understanding of surface wrinkling in polymer nanofibers and a technical approach for actively tuning the surface morphologies of polymer nanofibers for applications, e.g., high-grade filtration, oil-water separation, tissue scaffolding, etc.

Preliminary results of a prospective randomized trial comparing concurrent chemoradiotherapy plus adjuvant chemotherapy with radiotherapy alone in patients with locoregionally advanced nasopharyngeal carcinoma in endemic regions of china.

PURPOSE: A prospective randomized trial was performed to evaluate the efficacy of concurrent chemotherapy and adjuvant chemotherapy in patients with locoregionally advanced nasopharyngeal carcinoma (NPC) in endemic regions of China. METHODS AND MATERIALS: Between July 2002 and September 2005, 316 eligible patients were randomly assigned to receive either radiotherapy alone (RT) or chemoradiotherapy concurrent with adjuvant chemotherapy (CRT). All patients received 70 Gy in 7 weeks using standard RT portals and techniques. The CRT patients were given concurrent cisplatin (40 mg/m(2) on Day 1) weekly during RT, followed by cisplatin (80 mg/m(2) on Day 1) and fluorouracil (800 mg/m(2) on Days 1-5) every 4 weeks (Weeks 5, 9, and 13) for three cycles after completion of RT. All patients were analyzed by intent-to-treat analysis. RESULTS: The two groups were well-balanced in all prognostic factors and RT parameters. The CRT group experienced significantly more acute toxicity (62.6% vs. 32%, p = 0.000). A total of 107 patients (68%) and 97 patients (61%) completed all cycles of concurrent chemotherapy and adjuvant chemotherapy, with a median follow-up time of 29 months. The 2-year overall survival rate, failure-free survival rate, distant failure-free survival rate, and locoregional failure-free survival rate for the CRT and RT groups were 89.8% vs. 79.7% (p = 0.003), 84.6% vs. 72.5% (p = 0.001), 86.5% vs. 78.7% (p = 0.024), and 98.0% vs. 91.9% (p = 0.007), respectively. CONCLUSIONS: This trial demonstrated the significant survival benefits of concurrent chemotherapy plus adjuvant chemotherapy in patients with locoregionally advanced NPC in endemic regions of China.

Phase-field modeling of the formation of lamellar nanostructures in diblock copolymer thin films under inplanar electric fields.

Recent experiments show that external inplanar electric field can be employed to guide the molecular self-assembly in diblock copolymer (BCP) thin films to form lamellar nanostructures with potential applications in nanotechnology. We study this self-assembly process through a detailed coarse-grained phase-separation modeling. During the process, the free energy of the BCP films is modeled as the Ginzburg-Landau free energy with nonlocal interaction and electrostatic coupling. The resulting Cahn-Hilliard (CH) equation is solved using an efficient semi-implicit Fourier-spectral algorithm. Numerical results show that the morphology of order parameter formed in either symmetric or asymmetric BCP thin films is strongly influenced by the electric field. For symmetrical BCPs, highly ordered lamellar nanostructures evolved along the direction of the electric field. Phase nucleation and dislocation climbing in the BCP films predicted by the numerical simulation are in a good agreement with those observed in recent BCP electronanolithography. For asymmetrical BCPs, numerical simulation shows that nanodots are guided to align to the electric field. Furthermore, in the case of high electric field, nanodots formed in asymmetrical BCPs may further convert into highly ordered lamellar nanostructures (sphere-to-cylinder transition) parallel to the electric field. Effects of the magnitude of electric field, BCP asymmetry, and molecular interaction of BCPs on the self-assembly process are examined in detail using the numerical scheme developed in this study. The present study can be used for the prediction of the formation of nanostructures in BCP thin films and the quality control of BCP-based nanomanufacturing through optimizing the external electric fields.

Rippling of polymer nanofibers.

This paper studies the evolution mechanism of surface rippling in polymer nanofibers under axial stretching. This rippling phenomenon has been detected in as-electrospun polyacrylonitrile in recent single-fiber tension tests, and in electrospun polyimide nanofibers after imidization. We herein propose a one-dimensional nonlinear elastic model that takes into account the combined effect of surface tension and nonlinear elasticity during the rippling initiation and its evolution in compliant polymer nanofibers. The polymer nanofiber is modeled as an incompressible, isotropically hyperelastic Mooney-Rivlin solid. The fiber geometry prior to rippling is considered as a long circular cylinder. The governing equation of surface rippling is established through linear perturbation of the static equilibrium state of the nanofiber subjected to finite axial prestretching. The critical stretch and ripple wavelength are determined in terms of surface tension, elastic property, and fiber radius. Numerical examples are demonstrated to examine these dependencies. In addition, a critical fiber radius is determined, below which the polymer nanofibers are intrinsically unstable. The present model, therefore, is capable of predicting the rippling condition in compliant nanofibers, and can be further used as a continuum mechanics approach for the study of surface instability and nonlinear wave propagation in compliant fibers and wires at the nanoscale.

[Effects of Salvia miltiorrhiza on TGF-beta1, ROS and PAI-1 induced by angiotensin II in renal mesangial cells].

OBJECTIVE: To investigate the effect of Salvia miltiorrhiza on glomerulosclerosis induced by Ang II. METHOD: Rat mesangial cells were exposed to 100 nmol L(-1) Ang II. Meanwhile, we added S. miltiorrhiza injection of different concentrations to Mcs. PAI-1 mRNA and protein, TGF-beta1 in serum free MEM medium, and the level of cellular reactive oxygen species (ROS) were measured. RESULT: S. miltiorrhiza notably attenuated Ang II induced expression of PAI-1 in a concentration-dependent manner. Meanwhile, S. miltiorrhiza suppressed the production of TGF-beta1 and cellular ROS in mesangial cells. CONCLUSION: S. miltiorrhiza can alleviate glomerular sclerosis. The renoprotective effects of S. miltiorrhiza may be due to its ability to decrease Ang II -induced PAI-1 and TGF-beta1 secretion and cellular ROS level.

[Effects of manganismus on proliferation of neural stem cells in mice's hippocampus].

OBJECTIVE: To explore the effects of manganese poisoning on the proliferation of neural stem cells (NSCs) in mice's hippocampus. METHODS: The mice (weight 8 approximately 10 g) were divided into control group(CG) low-dose group(LDG) middle-dose group(MDG) and high-dose group(HDG)by intraperitoneal injection of 0, 5, 20, 50 mg x kg(-1) x d(-1) of manganese chloride dissolved in physiological saline. The ability of learning and memory was detected by Morris Water Maze, and the proliferation of NSCs in subgranular zone (SGZ) in these mice's hippocampus was also detected by immunohistochemistry. RESULTS: 1) Compared with the CG, the ability of learning and memory in all manganism group decreased significantly (P < 0.01) and this phenomenon in HDG was most notable (P < 0.01). Meanwhile, the ability of memory was negatively correlated with the dose of manganese chloride (r(s) = -0.598, P < 0.01), but the difference of swimming speed in every group was of no statistic significance. (2) The numbers of NSCs in proliferation period in SGZ of all manganism groups was much lower than that of CG (P < 0.01) negatively correlated with the dose of manganese chloride (r(s) = -0.666, P < 0.01). (3) The reduction of NSCs had a positive correlation to the depression of learning and memory (r(s) = 0.734, P < 0.01). CONCLUSIONS: Manganismus can affect the ability of learning and memory, which is probably caused by the inhalation of manganese on NSCs in hippocampus.

Sodium P-Aminosalicylic Acid Improved Manganese-Induced Learning and Memory Dysfunction via Restoring the Ultrastructural Alterations and γ-Aminobutyric Acid Metabolism Imbalance in the Basal Ganglia.

Excessive intake of manganese (Mn) may cause neurotoxicity. Sodium para-aminosalicylic acid (PAS-Na) has been used successfully in the treatment of Mn-induced neurotoxicity. The γ-aminobutyric acid (GABA) is related with learning and memory abilities. However, the mechanism of PAS-Na on improving Mn-induced behavioral deficits is unclear. The current study was aimed to investigate the effects of PAS-Na on Mn-induced behavioral deficits and the involvement of ultrastructural alterations and γ-aminobutyric acid (GABA) metabolism in the basal ganglia of rats. Sprague-Dawley rats received daily intraperitoneally injections of 15 mg/kg MnCl2.4H2O, 5d/week for 4 weeks, followed by a daily back subcutaneously (sc.) dose of PAS-Na (100 and 200 mg/kg), 5 days/week for another 3 or 6 weeks. Mn exposure for 4 weeks and then ceased Mn exposure for 3 or 6 weeks impaired spatial learning and memory abilities, and these effects were long-lasting. Moreover, Mn exposure caused ultrastructural alterations in the basal ganglia expressed as swollen neuronal with increasing the electron density in the protrusions structure and fuzzed the interval of neuropil, together with swollen, focal hyperplasia, and hypertrophy of astrocytes. Additionally, the results also indicated that Mn exposure increased Glu/GABA values as by feedback loops controlling GAT-1, GABAA mRNA and GABAA protein expression through decreasing GABA transporter 1(GAT-1) and GABA A receptor (GABAA) mRNA expression, and increasing GABAA protein expression in the basal ganglia. But Mn exposure had no effects on GAT-1 protein expression. PAS-Na treatment for 3 or 6 weeks effectively restored the above-mentioned adverse effects induced by Mn. In conclusion, these findings suggest the involvement of GABA metabolism and ultrastructural alterations of basal ganglia in PAS-Na's protective effects on the spatial learning and memory abilities.

Sodium p-Aminosalicylic Acid Reverses Sub-Chronic Manganese-Induced Impairments of Spatial Learning and Memory Abilities in Rats, but Fails to Restore γ-Aminobutyric Acid Levels.

Excessive manganese (Mn) exposure is not only a health risk for occupational workers, but also for the general population. Sodium para-aminosalicylic acid (PAS-Na) has been successfully used in the treatment of manganism, but the involved molecular mechanisms have yet to be determined. The present study aimed to investigate the effects of PAS-Na on sub-chronic Mn exposure-induced impairments of spatial learning and memory, and determine the possible involvements of γ-aminobutyric acid (GABA) metabolism in vivo. Sprague-Dawley male rats received daily intraperitoneal injections MnCl2 (as 6.55 mg/kg Mn body weight, five days per week for 12 weeks), followed by daily subcutaneous injections of 100, 200, or 300 mg/kg PAS-Na for an additional six weeks. Mn exposure significantly impaired spatial learning and memory ability, as noted in the Morris water maze test, and the following PAS-Na treatment successfully restored these adverse effects to levels indistinguishable from controls. Unexpectedly, PAS-Na failed to recover the Mn-induced decrease in the overall GABA levels, although PAS-Na treatment reversed Mn-induced alterations in the enzyme activities directly responsible for the synthesis and degradation of GABA (glutamate decarboxylase and GABA-transaminase, respectively). Moreover, Mn exposure caused an increase of GABA transporter 1 (GAT-1) and decrease of GABA A receptor (GABAA) in transcriptional levels, which could be reverted by the highest dose of 300 mg/kg PAS-Na treatment. In conclusion, the GABA metabolism was interrupted by sub-chronic Mn exposure. However, the PAS-Na treatment mediated protection from sub-chronic Mn exposure-induced neurotoxicity, which may not be dependent on the GABA metabolism.

Anderson Localization in Degenerate Spin-Orbit Coupled Fermi Gas with Disorder.

Competition between superconductivity and disorder plays an essential role in understanding the metal-insulator transition. Based on the Bogoliubov-de Gennes framework, we studied an 2D s-wave fermionic optical lattice system with both spin- orbit coupling and disorder are presented. We find that, with the increase of the strength of disorder, the mean superconducting order parameter will vanish while the energy gap will persist, which indicates that the system undergoes a transition from a superconducting state to a gapped insulating state. This can be confirmed by calculating the inverse participation ratio. We also find that, if the strength of disorder is small, the superconducting order parameter and the energy gap will decrease if we increase the strength of spin-orbit coupling and Zeeman field. In the large disorder limits, the increase of the strength of spin- orbit coupling will increase the mean superconducting order parameter. This phenomenon shows that the system is more insensitive to disorder if the spin-orbit coupling is presented. Numerical computing also shows that the whole system breaks up into several superconducting islands instead of being superconductive.

Sodium para-aminosalicylate protected cultured basal ganglia astrocytes from manganese-induced DNA damages and alteration of amino acid neurotransmitter levels.

Sodium para-aminosalicylate (PAS-Na) was first applied successfully in clinical treatment of two manganism patients with good prognosis. However, the mechanism of how PAS-Na protects against Mn-induced neurotoxicity is still elusive. The current study was conducted to explore the effects of PAS-Na on Mn-induced basal ganglia astrocyte injury, and the involvement of amino acid neurotransmitter in vitro. Basal ganglia astrocytes were exposed to 500 µM manganese chloride (MnCl2) for 24 hr, following by 50, 150, or 450 µM PAS-Na treatment for another 24 hr. MnCl2 significantly decreased viability of astrocytes and induced DNA damages via increasing the percentage of tail DNA and Olive tail moment of DNA. Moreover, Mn interrupted amino acid neurotransmitters by decreasing Gln levels and increasing Glu, Gly levels. In contrast, PAS-Na treatment reversed the aforementioned Mn-induced toxic effects on basal ganglia astrocytes. Taken together, our results demonstrated that excessive Mn exposure may induce toxic effects on basal ganglia astrocytes, while PAS-Na could protect basal ganglia astrocytes from Mn-induced neurotoxicity.

The influence of manganese treatment on the distribution of metal elements in rats and the protection by sodium para-amino salicylic acid.

Manganese (Mn) overexposure induced neurological damages, which could be potentially protected by sodium para-aminosalicylic acid (PAS-Na). In this study, we systematically detected the changes of divalent metal elements in most of the organs and analyzed the distribution of the metals in Mn-exposed rats and the protection by PAS-Na. Sprague Dawley (SD) rats received intraperitoneal injections of 15mg/kg MnCl2·4H2O (5d/week for 3 weeks), followed by subcutaneous (back) injections of PAS-Na (100 and 200mg/kg, everyday for 5 weeks). The concentrations of Mn and other metal elements [Iron (Fe), Copper (Cu), Zinc (Zn), Magnesium (Mg), Calcium (Ca)] in major organs (liver, spleen, kidney, thighbone and iliac bone, cerebral cortex, hippocampus and testes) and blood by Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES). The results showed that Mn overexposure significantly increased Mn in most organs, Fe and Zn in liver, Fe and Mg in blood; however decreased Fe, Cu, Zn, Mg and Ca in cortex, Cu and Zn in kidney, Cu and Mg in iliac bone, and Zn in blood. In contrast, PAS-Na treatment restored most changes particularly in cortex. In conclusion, excessive Mn exposure disturbed the balance of other metal elements but PAS-Na post-treatments could restore these alterations.

[Retrospective analysis of 934 nasopharyngeal carcinoma patients treated with conventional external beam radiotherapy alone].

OBJECTIVE: To analyze the clinical outcome of 934 primary nasopharyngeal carcinoma treated with conventional external beam radiotherapy alone. METHODS: 34 patients were treated from Jan. 1, 1999 to Dec. 31, 1999. The radiation fields were delineated according to the CT/MRI imaging findings on disease extent. Two lateral opposing isocentric portals with customized blockings were used for the nasopharynx and upper neck. The dose delivered to tumor in the nasopharynx was 68-70 Gy/2 Gy fraction/7 weeks. The doses delivered to the neck was 60-70 Gy/6-7 weeks for patients with positive lymph nodes and 50 Gy/5 weeks for the patients with negative lymph node. RESULTS: The 1-, 2-, 3- and 4-year overall survival rate (OS) was 89.5%, 81.9%, 78.1% and 75.7%, and metastasis-free survival rate (MFS) was 84.0%, 77.2%, 74.4% and 72.0%, respectively. The 1-, 2-, 3- and 4-year disease-free survival rate (DFS) was 80.8%, 73.1%, 68.5% and 65.1%, and the relapse-free survival rate (RFS) was 95.5%, 92.7%, 90.3% and 87.3%, respectively. The overall failure rate was 30.9% (289/934). At the end of the radiotherapeutic course, the percentage of residual disease was 14.6%. The 4-year loco-regional recurrence and distant metastasis rates after radiotherapy were 7.2% and 9.2% with a median time of 19.3 months and 12.8 months. CONCLUSION: It may be helpful to improve radiotherapy curative effect when the target is individually designed through improving irradiation technique according to CT/MRI findings and by shortening the overall course time, enhancing irradiation dose and strictly implementing QA/QC measures.