Dose estimation by chromosome aberration analysis and micronucleus assays in victims accidentally exposed to (60)Co radiation

The objective of this study was to assess the radiation exposure levels in victims of a (60)Co radiation accident using chromosome aberration analysis and the micronucleus assay. Peripheral blood samples were collected from three victims exposed to (60)Co 10 days after the accident and were used for the chromosome aberration and micronucleus assays. After in vitro culture of the lymphocytes, the frequencies of dicentric chromosomes and rings (dic+r) and the numbers of cytokinesis blocking micronuclei (CBMN) in the first mitotic division were determined and used to estimate radiation dosimetry. The Poisson distribution of the frequency of dic+r in lymphocytes was used to assess the uniformity of the exposure to (60)Co radiation. Based on the frequency of dic+r in lymphocytes, estimates of radiation exposure of the three victims were 5.61 Gy (A), 2.48 Gy (B) and 2.68 Gy (C). The values were estimated based on the frequencies of CBMN, which were 5.45 Gy (A), 2.78 Gy (B) and 2.84 Gy (C). The estimated radiation dosimetry demonstrated a critical role in estimating the radiation dose and facilitating an accurate clinical diagnosis. Furthermore, the frequencies of dir+r in victims A and B deviated significantly from a normal Poisson distribution. Chromosome aberration analysis offers a reliable means for estimating biological exposure to radiation. In the present study, the micronucleus assay demonstrated a high correlation with the chromosome aberration analysis in determining the radiation dosimetry 10 days after radiation exposure.

Electrochemical immunosensor based on colloidal carbon sphere array

A novel type of colloidal carbon sphere array (CSA) was developed for the fabrication of disposable electrochemical immunosensor. The CSA was successfully prepared on indium tin oxide (ITO) substrate in a simple manner and the scanning electron micrograph confirmed that a single-layered arrangement of the carbon spheres with its (111) plane paralleled the substrate's surface. The CSA modified electrode has a higher surface area and exhibits a more sensitive electrochemical response than a normal carbon-based electrode with the same geometric area. An Immunoglobin A (IgA) immunosensor was constructed by the covalent bonding of IgA antibody molecules with the CSA aided by large numbers of carboxyl groups on the surface of carbon spheres. The immunosensor exhibited a wide linear response to IgA ranging from 0.1 to 200 ng mL(-1) by electrochemical impedance spectroscopy (EIS) technique. The detection of IgA levels in three sera obtained from hospital samples showed acceptable accuracy.

Sonochemical synthesis and photocatalysis of porous Cu2O nanospheres with controllable structures

Porous Cu(2)O nanospheres with controllable structures were successfully synthesized by using ascorbic acid as the reducing agent and beta-cyclodextrin (beta-CD) as the capping agent via a sonochemical route, which was proved to be a green and convenient method for the controlled synthesis of porous Cu(2)O nanospheres. The crystal phase of the product was determined by the concentration of ascorbic acid, whereas its final structure was controlled by the ultrasonic irradiation time and the concentration of beta-CD. Moreover, porous Cu(2)O nanospheres exhibited enhanced photocatalytic activity compared with solid ones.

Curcumin attenuates acrylamide-induced cytotoxicity and genotoxicity in HepG2 cells by ROS scavenging

Acrylamide (AA), a proven rodent carcinogen, has recently been discovered in foods heated at high temperatures. This finding raises public health concerns. In our previous study, we found that AA caused DNA fragments and increase of reactive oxygen species (ROS) formation and induced genotoxicity and weak cytotoxicity in HepG2 cells. Presently, curcumin, a natural antioxidant compound present in turmeric was evaluated for its protective effects. The results showed that curcumin at the concentration of 2.5 microg/mL significantly reduced AA-induced ROS production, DNA fragments, micronuclei formation, and cytotoxicity in HepG2 cells. The effect of PEG-catalase on protecting against AA-induced cytotoxicity suggests that AA-induced cytotoxicity is directly dependent on hydrogen peroxide production. These data suggest that curcumin could attenuate the cytotoxicity and genotoxicity induced by AA in HepG2 cells. The protection is probably mediated by an antioxidant protective mechanism. Consumption of curcumin may be a plausible way to prevent AA-mediated genotoxicity.

Clinical report of three cases of acute radiation sickness from a (60)Co radiation accident in Henan Province in China

On 26 April 1999, three persons were accidentally exposed by high dose (60)Co irradiation. They suffered from severe (one case) or moderate (two cases) hemopoietic form of acute radiation sickness (ARS). As part of the comprehensive treatment, strict reverse isolation and granulocyte-macrophage colony-stimulating factor (GM-CSF) therapy were applied. All the patients recovered after an appropriate treatment for 83 days. In our experience, the correct diagnosis and effective treatment at an early stage proved to be helpful to the patients in pulling out from the critical stage of acute radiation sickness. To avoid menstruation by the female patient just in the critical stage, we modified her menstruation cycle by testosterone. In our view, GM-CSF should be given as early as possible with enough dosage for promoting early hematological reconstruction. The experience obtained from the medical management of these patients is valuable for the treatment of such patients in the future.

Inhibition of respiratory syncytial virus of subgroups A and B using deoxyribozyme DZ1133 in mice

Respiratory syncytial virus (RSV) commonly infects the upper and lower respiratory tracts. Currently, there is no effective treatment available. Deoxyribozymes are a potential therapeutic for RSV and their activity is based on the ability to bind and cleave complementary RNA sequences to inhibit protein expression. DZ1133 is a deoxyribozyme that targets the conserved genomic RNA sequence of the RSV nucleocapsid protein and has been shown to significantly inhibit various strains of RSV including subgroups A and B, standard A2 and CH18537 strains, and CQ381513, CQ381170, BJ01 and BJ04 strains. Treatment with DZ1133 decreased viral plaque formation in lungs of RSV-infected BALB/c mice. In addition, viral mRNA expression was reduced, airway inflammation was alleviated, and leukocyte counts were reduced in bronchoalveolar lavage fluid of RSV-infected mice. The antiviral effect of DZ1133 was dose-dependent (0.2-0.8mg) and more efficient than antisense oligonucleotide inhibition of gene expression. However, levels of cytokines TNF-alpha, IFN-gamma, IL-12, and IL-10 induced by RSV infection were not affected by DZ1133 treatment. Our data demonstrate that DZ1133 is a potential therapeutic agent against both subgroups A and B RSV infection in vivo.

Curcumin induces apoptosis through mitochondrial hyperpolarization and mtDNA damage in human hepatoma G2 cells

Curcumin, a major pigment of turmeric, is a natural antioxidant possessing a variety of pharmacological activities and therapeutic properties. But its mechanisms are unknown. In our previous study, we found that a 2-h exposure to curcumin induced DNA damage to both the mitochondrial DNA (mtDNA) and the nuclear DNA (nDNA) in HepG2 cells and that mtDNA damage was more extensive than nDNA damage. Therefore, experiments were initiated to evaluate the role of mtDNA damage in curcumin-induced apoptosis. The results demonstrated that HepG2 cells challenged with curcumin for 1 h showed a transient elevation of the mitochondrial membrane potential (DeltaPsim), followed by cytochrome c release into the cytosol and disruption of DeltaPsim after 6 h exposure to curcumin. Apoptosis was detected by Hoechst 33342 and annexin V/PI assay after 10 h treatment. Interestingly, the expression of Bcl-2 remained unchanged. A resistance to apoptosis for the corresponding rho0 counterparts confirmed a critical dependency for mitochondria during the induction of apoptosis in HepG2 cells mediated by curcumin. The effects of PEG-SOD in protecting against curcumin-induced cytotoxicity suggest that curcumin-induced cytotoxicity is directly dependent on superoxide anion O2- production. These data suggest that mitochondrial hyperpolarization is a prerequisite for curcumin-induced apoptosis and that mtDNA damage is the initial event triggering a chain of events leading to apoptosis in HepG2 cells.

General Sacrificial Template Method for the Synthesis of Cadmium Chalcogenide Hollow Structures

Semiconductor CdX (X=Te, Se, S) hollow structures have been successfully prepared by using Cd(OH)Cl precursors as a sacrificial template. The hollow structures can be hollow spheres or tubes by controlling the shape of the sacrificial template. The products were characterized by X-ray diffraction, transmission electron microscopy, scanning electron microscopy, and energy-dispersive spectrometry. The obtained results showed that the hollow structures had complementary shapes and sizes of the original sacrificial templates. This is a general method for the synthesis of cadmium chalcogenide hollow structures, and the method is simpler and more practical than direct synthesis of certain hollow structures, which further widens the avenue to using those materials that have been synthesized with various shapes to fabricate specific hollow structures.

Curcumin-induced genotoxicity and antigenotoxicity in HepG2 cells

Curcumin, a polyphenolic yellow pigment found in turmeric, is commonly used as a coloring agent in foods, drugs, and cosmetics. In our previous study, we found that low levels of curcumin did not increase the reactive oxygen species (ROS) formation and caused no damage to DNA in human hepatoma G2 (HepG2) cells, but at high doses, curcumin imposed oxidative stress and damaged DNA. In the present study, we are determined to investigate the genotoxic and antigenotoxic effects of curcumin using HepG2 cell line, a relevant in vitro model to detect the cytoprotective, antigenotoxic, and cogenotoxic agents. The results of micronucleus (MN) assays showed that, on one hand, curcumin at the high tested concentrations (8 and 16 microg/ml) displayed a small but significant increase in the frequency of MN, and on the other hand, it was observed that the low tested concentration (2 microg/ml) significantly reduced the MN formation induced by the chemotherapeutic agent cyclophosphamide. The present results indicate that curcumin shows both genotoxicity and antigenotoxicity depending on its concentration.

Diagnosis and therapy of hepatogenous diabetes

Hepatogenous diabetes, whose occurrence rate was found correlated with the types of hepatitis virus, is regarded as the secondary diabetes due to the damage of liver parenchyma, and it is characterized by high blood sugar and lowered glucose tolerance. Many studies demonstrated that insulin resistance, decrease of serum insulin-like growth factor-1, and elevation of growth hormone existed in patients with hepatogenous diabetes. Both liver damage and diabetes should be considered in the diagnosis and treatment of hepatogenous diabetes, which was different from those of type 2 diabetes, so we concluded the related studies in this article.

Ultrasonic-assisted size-controllable synthesis of Bi2Te3 nanoflakes with electrogenerated chemiluminescence

Bi(2)Te(3) hexagonal nanoflakes with controllable edge length ranging from approximately 150 nm to as small as approximately 10nm were synthesized via an ultrasonic-assisted disproportionation route, using Te powder and Bi(NO(3))(3).5H(2)O as raw materials. The mechanochemical effects of the ultrasonic irradiation accelerated the reaction and were helpful to obtain relatively small and uniform nanocrystals. The products were characterized by X-ray powder diffraction, X-ray photoelectron spectra, transmission electron microscopy, and selected area electron diffraction techniques. Electrogenerated chemiluminescence of as-prepared Bi(2)Te(3) was also reported for the first time.

EOF measurement by detection of a sampling zone with end-channel amperometry in microchip CE

A simple method for EOF measurement by detection of sampling zones with end-channel amperometry in microchip CE is developed. This method is based on the principle of the Kohlrausch regulating function (KRF). A dilute electroactive ionic species is added to the BGE as a continuously eluting electrophore which is used as a probe. When a BGE-like sample at a different concentration is injected, a peak of sampling zone appears and the migration time is related to EOF. In a microchip CE with hybrid PDMS/glass channel, a cathodic EOF of the hybrid glass/PDMS microchip was measured by end-channel amperometry; the effects of sample concentration and different probes on EOF rate were discussed. The present method was applied to monitor EOF rates in glass and in PDMS microchips. There was no significant difference between the values of EOF rates measured by the present method and the current-monitoring method. Detection of nonelectroactive analytes K(+), Na(+), and Li(+) can also be accomplished by the indirect amperometric method. Hence, the effective mobility of analyte can be accurately obtained.

Inhibition of respiratory syncytial virus in cultured cells by nucleocapsid gene targeted deoxyribozyme (DNAzyme)

Respiratory syncytial virus (RSV), which presents the primary cause of bronchiolitis and pneumonia among infants and causes significant morbidity and mortality in immunodeficient patients, remains a health problem worldwide. Unfortunately, an effective vaccine is currently unavailable and pharmacologic treatment needs further optimization for RSV disease. Because RSV is a non-segmented negative-strand RNA virus, it may be sensitive to the genome RNA cleaving by DNAzyme, an artificial nucleic acids molecule with high catalytic capability of cleaving complementary RNA molecules. Thus, RSV-targeted DNAzymes potentially present as a therapeutic candidate of RSV diseases. In this study, DNAzymes targeting the RSV genomic RNA or mRNA were designed and synthesized, one of which (DZn1133) did cleave RSV RNA in vitro, inhibit the transcription and expression of F viral gene, reduce the RSV yield by about 7 logs and protect more than 90% RSV-infected Hep-2 cells from a cytopathic effect at 8 microM. Moreover, 10 wild RSV strains isolated from clinic patients including both subgroups A and B were all suppressed by DZn1133 with greater anti-RSV activity than antisense DNA or ribavirin.

Sonochemical synthesis of CdS and CdSe nanowires

A convenient sonochemical route was developed to fabricate one-dimensional (1D) CdS or CdSe assemblies via a simple template method with two-steps: Firstly, the colloid one dimensional cadmium hydroxide particles were prepared as templates under sonication; then, the colloid particles were converted into 1D CdS or CdSe assemblies via a replacement reaction after the surface nucleation and crystal growth processes. The as-prepared CdS and CdSe nanowires were characterized by XRD, TEM, XPS, and UV-visible Spectroscopy. The effects of the ultrasonic irradiation were discussed. It is believed that the ultrasound irradiation played a positive role in both the assembly of the colloid cadmium hydroxide particles into the 1D structure and the growth of CdSe and CdS nanowires. The effects of pH on the morphologies of the cadmium hydroxide template were also discussed. The band gaps of the as-prepared 1D CdSe and CdS assemblies were calculated to be 3.1 eV and 4.9 eV, respectively, indicating the quantum size effect. The as-prepared products might have potential applications in nanodevices in future.

Ultrasonic-Assisted Synthesis of Monodisperse Single-Crystalline Silver Nanoplates and Gold Nanorings

A simple sonochemical route was developed for the crystal growth of uniform silver nanoplates and ringlike gold nanocrystals in a N,N-dimethylformamide solution. The platelike structures were generated from the selective growth on different crystal planes in the presence of poly(vinylpyrrolidone) and the ultrasonic-assisted Ostwald ripening processes. The silver nanoplates in solution served as the templates for the synthesis of ringlike gold crystals via a displacement reaction. Both the silver nanoplates and gold nanorings were highly oriented single crystals with (111) planes as the basal planes.

[Primary study on speech training of palatalized misarticulation]

OBJECTIVE

In this paper, differences in 10 palatalized misarticulation patients between pre-and post-speech training were reported to discuss the training methods of palatalized misarticulation.

METHODS

10 palatalized misarticulation patients (6 male, 4 female) with the age of 4-14 years were included in the study. All the patients had undergone systematic speech therapy,and their speech intelligibilities were analyzed.

RESULTS

All patients' speech intelligibilities after training were significantly higher than those before training. /s/, /z/, /c/, /d/, /t/, /zh/, /ch/, /sh/, /j/, /q/ and /x/ were often involved.

CONCLUSION

Palatalized misarticulation was caused by abnormal palato-lingual contact which leads to decreasement of speech intelligibility. Speech training is the only method to correct the wrong articulation position and articulation method. The key of training methods for palatalized misarticulation is to plane the dorsum and release the tongue's retroflex.

[A study on speech training methods for patients following cleft palate repair]

OBJECTIVE:This study is to improve speech articulations of patients following cleft palate repair. METHODS: 20 cases were treated with systemic speech trainning. The methods included testing speech articulations of pre-and post-training blowing and systemic speech training whose program was consonant (first step), syllable (second), word (third), sentence (forth), and (fifth). RESULTS: It is showed that their articulations improved from 48.1% to 97.1% on average,and,the improvement in speech was highly significant statistically(P<0.0001).The younger the patient was,the shorter the training circle was. CONCLUSION: Speech training can correct habit of compensatory pathologic articulation and improve articluation of patient following cleft palate repair.

[Quantitative study of velopharyngeal function post-palatoplasty]

The computer of nasopharyngeal fiberscope(NPF) for quantitative analysis was carried out to assess the palate articulation of 43 subjects,and normal articulation of 60 subjects.The rest,/a/,/s/and /m/ articulation of NPF pictures were calculated for veloparyngreal function via computer.

[Establishment and clinical application of Chinese language clear degree]

This study was established the Chinese language of clear degree.The subjects of this study consisted of 50 patients with postoperative of cleft lip and palate,congenital velopharyngeal incompetence,and 30 control group were normal articulation of persons.The results of this study may be helpful for further clinic of the cleft lip and palate patients of speech therapeutics.

[Evaluation of velopharyngeal function after later surgical repair of cleft palate. ]

This study detected 60 cases of patients of later surgical cleft palate repairing with different operative procedures,based on nasopharyngeal fiberscope and image processing detective system of nasopharyngeal function.They were divided into two groups,30 cases with Furlow's double reversing Z plasty,and others with traditional palatoplasty.The results were as follows:the type of velopharyngeal closure with later palatoplasty mainly were circus,semi-circus,and the rate of operative success only was 46.6%,which was lower than other reports.Author described that compensation of lateral and posterior pharyngeal wall made the type of velopharyngeal closure.The elder the age,the more the compensation is.For the late cleft palate repair,although the variable surgical procedure made a condition for speech improvement, patients with later cleft palate repair still can't improve their phonation.

Immunoglobulin G subclass deficiency in children with recurrent respiratory tract infections

With monoclonal antibodies serum immunoglobulin G(IgG) subclasses were measured in seventy children aged 2 to 13 years with recurrent respiratory tract infections including upper respiratory tract infections, otitis media, sinusitis, asthmatic bronchitis and pneumonia. 211 healthy, aged-matched children served as control. IgG subclass deficiency was found in 19 out of the 70 patients (27.1%, single IgG1 deficiency in 7, IgG2 deficiency in 4, combined IgG1-IgG3 deficiency in 5, IgG1-IgG2-IgG3-IgG4 deficiency, IgG1-IgG2-IgG4 deficiency and IgG2-IgG4 deficiency each in 1). The incidence of IgG subclass deficiencies was in the sequence as follows: IgG1, 20%; IgG2, 10%; IgG3, 8.6% and IgG4, 4.3%. The results suggest that IgG subclass deficiency indicate a common disorder in children with recurrent respiratory tract infections.

Immunoglobulin G subclasses in serum and circulating immune complexes in patients with Kawasaki syndrome

IgG subclass concentrations in sera of 17 patients with Kawasaki syndrome were determined. Significantly increased IgG1 (P less than 0.001) and IgG3 (P less than 0.001) were found in the patients compared with 22 age-matched healthy children, whereas IgG2 and IgG4 were normal or slightly decreased. IgG immune complexes were measured by protein A-enzyme-linked immunosorbent assay (ELISA) combined polyethylene glycol precipitations. Eight of 17 patients (47.1%) were found to have circulating immune complexes (CIC) values above the normal control range (geometric mean +2 SD). IgG subclass composition in CIC was analyzed. The subclasses in CIC were predominantly IgG1 and IgG3. Because the antibody responses to different antigens exhibit IgG subclass restriction, it would suggest that the change of serum and CIC IgG subclasses in Kawasaki syndrome may have relevance to the pathogenesis of the disease.

The treatment of primary vertebral tumors by radical resection and prosthetic vertebral replacement

The basic principles for the treatment of primary vertebral tumors include radical resection of the tumor, insertion of a prosthetic vertebral body, and bone grafting within and around the prosthetic vertebral body. Since 1970, the authors have treated 12 cases with this procedure. In order to improve the vertebral prosthesis, 94 dried adult vertebral column specimens were studied. The anterior cortex of each vertebral body was thicker than the posterior cortex. The thickness of the anterior cortex of the dorsolumbar vertebral bodies progressively increases from the proximal to caudal vertebra. The lower lumbar vertebrae are therefore almost twice as thick as the upper dorsal vertebrae. The cortices of the vertebral bodies, especially the anterior cortex, serve as a strut against the pressure of the prosthesis. Four types of prostheses were used. The Type 1 prosthesis failed to take into account the anatomic features of the dorsolumbar vertebral bodies in cross section. Types 2, 3, and 4 are modified versions with specific indications for their use.