Expression of Wnt-5a and its clinicopathological significance in hepatocellular carcinoma

BACKGROUND

The functions of Wnt-5a in human cancers are controversial and unclear.

AIM

To investigate the clinical significance of Wnt-5a expression in hepatocellular carcinoma.

PATIENTS AND METHODS

Real-time quantitative Reverse transcriptase Polymerase Chain Reaction was done to evaluate Wnt-5a gene expression. Wnt-5a, beta-catenin, E-cadherin and Ki-67 were examined immunohistochemically in 114 hepatocellular carcinoma cases.

RESULTS

Compared to normal tissue, Wnt-5a mRNA expression was clearly increased in hepatocellular carcinoma, chronic hepatitis and cirrhosis. On immunohistochemistry, immunostaining of Wnt-5a showed a bell-shaped pattern: low to undetectable levels were present in normal tissue and in tumour samples, whereas strong immunostaining was seen in chronic hepatitis, cirrhosis and dysplastic liver cells. Reduction or loss of Wnt-5a protein expression was found in 80.7% of hepatocellular carcinoma cases (n=92) and was significantly associated with higher tumour stage (p<0.001), serum AFP level (p=0.025), low membranous expression of E-cadherin (p<0.0001) and beta-catenin (p=0.036) and high Ki-67 labelling indices (LIs, p=0.001).

CONCLUSION

Wnt-5a mRNA and protein levels are higher than normal in hepatitis and cirrhosis and appear to be related to the presence of hepatitis B virus infection. However, Wnt-5a protein expression is frequently lost in hepatocellular carcinoma; this supports the notion that this protein has a tumour suppressor function in hepatocellular carcinoma.

Evaluation of Free Flaps Transferred by Microvascular Anastomosis in Oral and Maxillofacial Surgery

The authors discuss indications for the use of microvascular free flaps transferred to the oral and maxillofacial region. A series of 139 cases, involving 145 free flaps, is reported over a three year period. The overall success rate for all types of flaps was 89.3%. Advantages and disadvantages of the use of various flaps are presented and suggestions are offered to avoid complications.

[Investigation of electrocatalytic reduction of oxalic acid on Pb electrode through in situ FTIR reflection spectroscopy]

Electrochemical in situ Fourier transform infrared reflection spectroscopy was used in the investigation of electrocatalytic reduction of oxalic acid on Pb electrode. The multi-step potential FTIRS and time-resolved FTIRS procedures were used in the present study. The results of MSFTIRS demonstrate that glyoxylic acid could be detected below -0.70 V. The quantity of glyoxylic acid cumulated on Pb electrode surface reaches a maximum at -0.85 V, then it decreases as electrode potential is further decreased. Meanwhile the C-O stretching vibration of -CH2OH group at around 1 093 cm(-1) could be detected at -0.95 V. It was revealed that all the produced glyoxylic acid may be reduced further into glycolic acid at potentials below -1.50 V. Furthermore, none of other new substances could be detected at more negative potentials, which indicated that glycolic acid could not be further reduced. The results of time resolved Fourier transform infrared reflection spectroscopy at -0.75 V indicate that the integrated intensity of the IR band at about 1 750 cm(-1) for the stretching vibration of C=O (-CHO) linearly increases with the reaction time. The TRFTIR spectra at -1.60 V show that not only the IR absorption of C=O (HOOC-CHO) stretching is observed, but also that of C-O (-CH2OH) stretching at about 1 093 cm(-1) can be seen. The current study demonstrated that electrochemical in situ Fourier transform infrared reflection spectroscopy is a powerful tool for the study of electrosynthesis processes, and for the detection of each species involved in the reaction at molecular level. The results are of significance to understand the reaction mechanism of electrocatalytic reduction of oxalic acid.

Synthesis of tetrahexahedral platinum nanocrystals with high-index facets and high electro-oxidation activity

The shapes of noble metal nanocrystals (NCs) are usually defined by polyhedra that are enclosed by {111} and {100} facets, such as cubes, tetrahedra, and octahedra. Platinum NCs of unusual tetrahexahedral (THH) shape were prepared at high yield by an electrochemical treatment of Pt nanospheres supported on glassy carbon by a square-wave potential. The single-crystal THH NC is enclosed by 24 high-index facets such as {730}, {210}, and/or {520} surfaces that have a large density of atomic steps and dangling bonds. These high-energy surfaces are stable thermally (to 800 degrees C) and chemically and exhibit much enhanced (up to 400%) catalytic activity for equivalent Pt surface areas for electro-oxidation of small organic fuels such as formic acid and ethanol.

Electrochemical preparation and structural characterization of Co thin films and their anomalous IR properties

Nanometer scale cobalt thin films of different structures and thicknesses supported on glassy carbon were prepared by electrochemical deposition under cyclic voltammetric conditions (denoted nm-Co/GC(n)). The thickness of Co thin films was altered systematically by varying the number (n) of potential cycling within a defined potential range in electrodeposition. Electrochemical in situ scanning tunneling microscopy (STM) and ex situ scanning electron microscopy (SEM) were employed to characterize the surface structure of Co thin films. It has been illustrated that the Co thin films were uniformly composed of Co nanoparticles, whose structure and size varied with increasing n. The structure of nanoparticles inside the Co thin films underwent a transition from bearded nanoparticles to multiform nanoparticles and finally to hexagonal nanosheets, accompanying with an increase of average size. In situ FTIR reflection spectroscopic studies employing CO adsorption as probe reaction revealed that the Co thin films all exhibited anomalous IR properties; that is, along with their different nanostructures they presented abnormal IR effects, Fano-like IR effects, and surface-enhanced IR absorption effects. CO adsorbed on Co thin films dominated by bearded nanoparticles yielded abnormal IR absorption bands; that is, the direction of the bands is inverted completely, with enhanced intensity in comparison with those of CO adsorbed on a bulk Co electrode. The enhancement of abnormal IR absorption has reached a maximal value of 26.2 on the nm-Co/GC(2) electrode. Fano-like IR features, which describe the bipolar IR bands with their positive-going peak on the low wavenumbers side, were observed in cases of CO adsorbed on Co thin films composed mainly of multiform nanoparticles, typically on the nm-Co/GC(8) electrode. IR features were finally changed into surface-enhanced IR absorption as CO adsorbed on the nm-Co/GC(30) electrode, on which the Co thin film is dominated by Co hexagonal nanosheets.

Electrochemical preparation of platinum nanothorn assemblies with high surface enhanced Raman scattering activity

Platinum nanothorn assemblies with sharp tips and edges were prepared, which exhibit high surface enhanced Raman scattering (SERS) activity and yield an enhancement factor as high as 2000 for adsorbed pyridine.

Differential diagnosis between Crohn's disease and intestinal tuberculosis in China

To evaluate the values of clinical findings in differential diagnosis between Crohn's disease (CD) and intestinal tuberculosis (ITb), so that better diagnosis strategies could be found, we analysed the records of 30 patients with ITb and 30 patients with CD retrospectively. We reviewed the cardinal symptomatic and physical, radiological, colonoscopic, pathological findings in the patients. Some cardinal symptomatic and physical, radiographic and colonscopic features of CD and ITb were positive correlation. Its Pearson correlation coefficients were 0.976, 0.953 and 0.961, respectively (p = 0.000, 0.003 and 0.000). Some histological features of CD and ITb had no correlation. Its Pearson correlation coefficient was 0.140 (p = 0.765). It is difficult to differentiate CD from ITb in clinical practice. The differential diagnosis depends largely upon colonoscopy and histopathology.

In Situ STM Studies of Electrochemical Growth of Nanostructured Ni Films and Their Anomalous IR Properties

We have extended the study of anomalous IR properties, which were initially discovered on nanostructured films of platinum group metals and alloys, to nanostructured films of nickel, a member of the iron group triad, and broadened the fundamental knowledge on this subject. Nanostructured thin films of nickel supported on glassy carbon [nm-Ni/GC(n)] were prepared by electrochemical deposition under cyclic voltammetric conditions, and the thickness of films was altered systematically by varying the number (n) of potential cycling within a defined potential range for electrodeposition. Electrochemical in situ scanning tunneling microscopy (STM) was employed to monitor the electrochemical growth of nanostructured Ni films. These in situ STM images illustrated that, along the increase of the film thickness, Ni films have undergone a transformation from layer structure to island structure and finally to lumpish arris structure. Investigations by in situ FTIR spectroscopy employing adsorbed CO as the probe revealed that these nanostructures of Ni films yield abnormal IR features, Fano-like IR features, and normal IR features, respectively. The IR bands of CO adsorbed on Ni thin films of a layer structure were inverted in their direction and enhanced in their intensity up to 15.5 times on an nm-Ni/GC(4) electrode. The Fano-like IR features, which are defined as a bipolar band with its negative-going peak on the low wavenumber side and its positive-going peak on the high wavenumber side, are observed for the first time on Ni thin films of an island nanostructure, i.e., at the nm-Ni/GC(16) electrode. IR features changed to normal absorption in CO adsorbed on the nm-Ni/GC(25) electrode, i.e., that with lumpish arris nanostructured Ni film of a larger thickness.

Limit on the electron neutrino magnetic moment from the kuo-sheng reactor neutrino experiment

A search of neutrino magnetic moment was carried out at the Kuo-Sheng Nuclear Power Station at a distance of 28 m from the 2.9 GW reactor core. With a high purity germanium detector of mass 1.06 kg surrounded by scintillating NaI(Tl) and CsI(Tl) crystals as anti-Compton detectors, a detection threshold of 5 keV and a background level of 1 kg(-1) keV(-1) day(-1) at 12-60 keV were achieved. Based on 4712 and 1250 h of reactor ON and OFF data, respectively, the limit on the neutrino magnetic moment of mu(nu;(e))<1.3x10(-10)mu(B) at 90% confidence level was derived. An indirect bound of the nu;(e) radiative lifetime of m(3)(nu)tau(nu)>2.8x10(18) eV(3) s can be inferred.

Photoluminescent metal-sulfur clusters derived from tetrathiometalates: metal-to-metal charge-transfer excited states of d0-d10 heterobimetallic sulfido clusters with bulky phosphine ligands

Reactions of MS4(2-) (M = Mo, W) with M'(PCy3)X (M'=Ag/Au, X= ClO4/Cl) and [Cu2(dcpm)2(MeCN)2](ClO4)2 (dcpm = bis(dicyclohexylphosphino)methane) afforded heterometallic sulfido clusters [M'2(PCy3)2(MS4)] (M=Mo, M'=Au: 2; M=W, M'=Ag: 3, Au: 4) and [Cu4(dcpm)4(MS4)](ClO4)2 (M=Mo: 5 x (ClO4)2, W: 6 x (ClO4)2), all of which, except 4, have been characterized by X-ray structure determination. Clusters 5 x(ClO4)2 and 6 x (ClO4)2 feature unusual 16-membered [Cu4P5C4] metallamacrocycles formed on the respective tetrathiometalate anion templates and have unusually long Cu-S bonds and Cu...M distances for metal sulfur clusters that contain a saddle-shaped [Cu4MS4] core. Low-energy absorption bands are observed in their electronic spectra at approximately 562 and 467 nm, respectively, assignable to MMCT transitions; quasireversible reduction waves are observed with E(1/2) = -1.43 (52+) and -1.78 V (62+) versus FeCp2(0/+); and they are emissive either in the solid state or in solution. The emission of 6(2+) can be quenched by both electron acceptors, such as methylviologen, or electron donors, such as aromatic amines, with the excited state reduction potential E(62+*/6+) estimated to be approximately 1.13V versus a normal hydrogen electrode.

Interaction between dioxoruthenium(VI) porphyrins and hydroxylamines: coordination of N-substituted hydroxylamine to ruthenium and X-ray crystal structures of ruthenium complexes with a unidentate nitrosoarene ligand

The interactions between dioxoruthenium(VI) porphyrins 1 with N-phenylhydroxylamine or unsubstituted hydroxylamine are described. Reaction of complexes 1 with excess PhNHOH leads to isolation of bis(nitrosobenzene)ruthenium(II) porphyrins 3 and mono(nitrosobenzene)ruthenium(II) porphyrins 4. Both the types of ruthenium complexes are characterized by 1H NMR, IR, and UV/Vis spectroscopy, and mass spectrometry. The X-ray structure determinations on [Ru(II)(TPP)(PhNO)2] (3a), [Ru(II)(2,6-Cl-TPP)(PhNO)2] (3e), and [Ru(II)(4-MeO-TPP)(PhNO)(PhNH2)] (4d) (TPP tetraarylporphyrin) disclose a unidentate nitrosoarene coordination in all these complexes, with Ru-N(PhNO) bond lengths of 2.003(3) (3a, average), 1.991(3) (3e, average), and 2.042(2) A (4d). In the case of 4d, the Ru-N(PhNH2) bond length is found to be 2.075(3) A. Mechanistic investigations reveal the formation of intermediates [Ru(II)(Por)(PhNO)(PhNHOH)] (5; Por=porphyrin), a ruthenium complex with N-substituted hydroxylamine ligand, in the "1 + PhNHOH" system. The Ru-NH(OH)Ph moiety in 5 undergoes no rapid exchange with free PhNHOH in solution at room temperature, as revealed by 1H NMR spectroscopy. Unlike the interaction between complexes 1 and PhNHOH, reaction of such complexes with NH2OH affords nitrosylruthenium(II) porphyrins [Ru(II)(Por)(NO)(OH)] (6).

Reactive oxygen species uncouple external horizontal cells in the carp retina and glutathione couples them again

We have investigated the effect of free radicals on the electrical gap junctions between horizontal cells in the carp retina. In our previous study, L-buthionine sulfoximine, an inhibitor of glutathione synthesis, caused uncoupling of horizontal cells four days after injection. In the present study, we have used paraquat, a generator of exogenous reactive oxygen species, to investigate whether it was the depletion of glutathione or an increase in the level of reactive oxygen species which resulted in horizontal cell uncoupling after L-buthionine sulfoximine injection. Intracellular recordings were made from L-type horizontal cells at various time-points after intravitreal injection of paraquat. Injection of 25nmol paraquat caused an increase in response amplitude to central spot light stimuli by two days after injection, which continued for a further two to three days and had almost disappeared by seven days after injection. There was also a sharp increase in reactive oxygen species production, peaking at four days and disappearing by seven days after injection, and an accompanying depletion and a restoration of glutathione levels with a similar time-course. Marking cells with Lucifer Yellow clearly illustrated uncoupling of horizontal cells after paraquat injection. If paraquat and L-buthionine sulfoximine were injected simultaneously, the increase in response to central spots was observed as early as one day after injection. This response amplitude was not more enhanced than that observed after L-buthionine sulfoximine injection alone, although a dramatic increase in the level of reactive oxygen species was observed. From these results, we suggest that reactive oxygen species are involved in uncoupling, while recovery from uncoupling is dependent on glutathione. Furthermore, we conclude that a balance between glutathione and reactive oxygen species levels is the most important factor controlling gap junctional intercellular communication of L-type horizontal cells in the carp retina.

Asymmetric inter- and intramolecular cyclopropanation of alkenes catalyzed by chiral ruthenium porphyrins. Synthesis and crystal structure of a chiral metalloporphyrin carbene complex

Extensive investigations of asymmetric intermolecular cyclopropanation of terminal alkenes with diazoacetates catalyzed by ruthenium porphyrin [Ru(P*)(CO)(EtOH)] (1, H2P = 5,10,15,20-tetrakis[(1S,4R,5R,8S)-1,2,3,4,5,6,7,8-octahydro-1,4:5,8-dimethanoanthracene-9-yl]porphyrin) and the application of catalyst 1 to asymmetric intramolecular cyclopropanation of allylic or homoallylic diazoacetates are described. The intermolecular cyclopropanation of styrene and its derivatives with ethyl diazoacetate afforded the corresponding cyclopropyl esters in up to 98% ee with high trans/cis ratios of up to 36 and extremely high catalyst turnovers of up to 1.1 x 10(4). Examination of the effects of temperature, diazoacetate, solvent, and substituent in the intermolecular cyclopropanation reveals that (i) both enantioselectivity and trans selectivity increase with decreasing temperature, (ii) sterically encumbered diazoacetates N2CHCO2R, such as R = Bu(t), and donor solvents, such as diethyl ether and tetrahydrofuran, are beneficial to the trans selectivity, and (iii) electron-donating para substituents on styrene accelerate the cyclopropanations, with the log(k(X)/k(H)) vs sigma(+) plot for para-substituted styrenes p-X-C6H4CH=CH2 (X = MeO, Me, Cl, CF3) exhibiting good linearity with a small negative rho(+) value of -0.44 +/- 0.09. In the case of intramolecular cyclopropanation, complex 1 promoted the decomposition of a series of allylic diazoacetates to form the cyclopropyl lactones in up to 85% ee, contributing the first efficient metalloporphyrin catalyst for an asymmetric intramolecular cyclopropanation. Both the inter- and intramolecular cyclopropanations were proposed to proceed via a reactive chiral ruthenium carbene intermediate. The enantioselectivities in these processes were rationalized on the basis of the X-ray crystal structures of closely related stable chiral carbene complexes [Ru(P*)(CPh2)] (2) and [Ru(P*)(C(Ph)CO2CH2CH=CH2)] (3) obtained from reactions of complex 1 with N2CPh2 and N2C(Ph)CO2CH2CH=CH2, respectively.

[The cloning of apple ferritin gene (Apfl) from Malus xiaojinensis Cheng et Jiang and its structure analysis]

The special primers were designed based on the sequence information of plant ferritin genes reported in the literature and used for polymerase chain reaction (PCR) with the genomic DNA of Malus xiaojinensis Cheng et Jiang in an attempt to clone apple ferritin gene. A single fragment of 771 bp was successfully obtained from the PCRs and cloned in this study. The sequence and homology analysis results of the fragment showed that the deduced amino acids of the fragment had a ninety-nine percent homology to that of the soybean ferritin gene reported by Lescure et al. (1991). A comparison in details of the nucleotide sequence of the clone and that of the soybean ferritin gene showed that they consisted of the same open reading frame (ORF, 753 bp) and that the cloned fragment had complete initial and stop codes. Within the ORF no introns were found and there were no nucleotide difference in the transit peptide region (TP) of the gene, but five nucleotide mutations were found in the mature peptide region (MP), among which four were synonymous mutations.

[Postnatal development of brainstem auditory evoked potential and middle latency response in rats]

AIM

To compare the postnatal development of brainstem auditory evoked potential (BAEP) with that of middle latency response (MLR) in rats.

METHODS

The postnatal development of BAEP and MLR had been studied continuously for 10 weeks in the same groups of rat Pups.

RESULTS

BAEP and MLR emerged at day 14 and 17 respectively. The peak latencies of BAEP's waves shortened systematically with age, especially during 3-4 weeks. The peak latency of wave I reached adult value at day 29, and the peak latencies of the rest waves reached adult ones at day 70. However, the peak latencies of wave Po and Na in the first time evoked MLR had already been at adult values. Though the peak latencies of wave Pa, Nb and Pb also shortened with age, they reached adult ones quickly at day 20-23. The wave amplitudes of BAEP's wave I ,III, IV and MLR's wave Nb, Pb increased quickly with age during 3-4 weeks. Their peak values were much bigger than adult ones and then decreased gradually.

CONCLUSION

The postnatal development of BAEP and MLR proceeded in a similar way in rats, but the peak latencies of MLR reached adult values much earlier than that of BAEP.

Biosynthetic Studies on the Cyclopentane Ring Formation of Allosamizoline, an Aminocyclitol Component of the Chitinase Inhibitor Allosamidin

Allosamizoline (1) is an aminocyclitol component of allosamidin, a Streptomyces metabolite, and has a cyclopentane ring originated from D-glucosamine. Biosynthesis of the cyclopentane ring was studied by feeding experiments with a variety of deuterium-labeled glucosamine and glucose. In the feeding experiments with [3-(2)H]- and [4-(2)H]-D-glucosamine and [1-(2)H]-D-glucose, deuterium was incorporated into C-3, C-4, and C-1 of 1, respectively. On the other hand, feeding experiments with [5-(2)H]- and [6,6-(2)H(2)]-D-glucosamine showed that deuterium on C-5 and one of the two deuterium atoms on C-6 of glucosamine were lost during the cyclopentane ring formation of 1. In the feeding experiments with (6R)- and (6S)-[6-(2)H(1)]-D-glucose, the (6R)-deuterium of glucose was incorporated into the proS position on C-6 of 1, but the (6S)-deuterium of glucose was not incorporated into 1. These results suggested that an intermediate with a 6-aldehyde group is involved in the biosynthesis of the cyclopentane ring moiety of 1 and overall inversion of stereochemistry of the C-6 methylene group occurred by stereospecific oxidation and reduction on C-6 during the formation of 1. The 6-aldehyde intermediate may play a key role in the biosynthetic step(s) of cyclization to form the cyclopentane ring and/or deoxygenation at C-5.

[Expression of single-chain Fv antibody for anti-beet necrotic yellow vein virus in Escherichia coli]

The heavy chains variable region gene (VH) of monoclonal antibody against beet necrotic yellow vein virus (BNYVV) was amplified from total DNA extracted from anti-BNYVV hybridoma cells by PCR. Sequencing showed that the VH belongs to mouse subgroup II(A) and contains 360 bp, which code one hundred and twenty amino acids. The VH and VL genes were inserted into a plasmid which contains a linker sequence for constructing scFv gene. The new vector named pTC scFv. The scFv was produced in Escherichia coli and appeared binding activity with BNYVV antigen by ELISA method.

Simultaneous nitrogen and phosphorus removal under low dissolved oxygen conditions

A full-scale test was operated by using low dissolved oxygen activated sludge process to enhance biological nitrogen and phosphorus removal. When the influent concentrations of CODcr, TN and TP varied in a range of 352.9 mg/L-1338.2 mg/L, 34.4 mg/L-96.3 mg/L, and 2.21 mg/L-24.0 mg/L, the average removal efficiencies were 94.9%, 86.7% and 93.0%, respectively. During the test period of two months, effluent means of CODcr, BOD5, NH3-N, TN and TP were below 50 mg/L, 25 mg/L, 10 mg/L and 1.0 mg/L, respectively. The low dissolved oxygen activated sludge process has a simple flow sheet, fewer facilities and high N and P removal efficiency. It is very convenient to retrofit the conventional activated sludge process with the above process.

Prevalence of antibodies to Toxoplasma gondii in the sera of rare wildlife in the Shanghai Zoological Garden, People's Republic of China

The prevalence of antibodies to Toxoplasma gondii in the sera of rare wildlife in the Shanghai Zoological Garden, PR China, was examined using a modified agglutination test (MAT) and an enzyme-linked immunosorbent assay (ELISA). Forty-one (35%) of 117 animals belonging to two classes, 10 orders, 18 families, 37 genera and 52 species (including sub-species) were sero-positive for MAT. By MAT, T. gondii antibodies were found in 11.1% (4/36) of birds, in 25% (4/16) of primates, in 69.4% (25/36) of carnivores and in 27.6% (8/29) of herbivores. Thirty-three (33.7%) of 98 animals tested by protein A ELISA were sero-positive. By ELISA, T. gondii antibodies were found in none of 36 birds, in 33.3% (4/12) of primates, in 87.1% (27/31) of carnivores and in 10.5% (2/19) of herbivores.

[Construction of silkworm RAPD molecular linkage map]

In this research, a RAPD linkage map of Bombyx mori was constructed with Dazao/C108 and their F2 generation. The map consists of 182 RAPD loci, of which 103 loci come from Dazao and from the first 23 linkage groups and the other 79 loci come from C108 and form the second 16 linkage groups. This map covered a total genetic distance of over 1,148.3 cM (centimorgan). It could be integrated with the SADF map of the same materials constructed in our laboratory and the corresponding RFLP linkage map.

Synthesis of a new chiral ligand, 6, 6'-dihydroxy-5, 5'-biquinoline (BIQOL) and its applications in the asymmetric addition of diethylzinc to aldehydes

A new chiral ligand 6, 6'-dihydroxy-5, 5'-biquinoline (BIQOL, 2) was prepared via Cu2+ mediated coupling. The resolution was carried out by separating the corresponding ditrifluomethanesulfonate on chiral column. When applied to the enantioselective addition of diethylzinc to aromatic aldehydes, this ligand induced the reaction with enantioselectivity equivalent to that induced by BINOL. The effects of solvent and reaction temperature on enantioselectivity were also studied.

[Experimental study of mandibular reconstruction with Sr-HAP]

OBJECTIVE

Different ration of Sr-HAP was implanted in animals to study the bioreactions in order to prepare for the clinical applications in future.

METHODS

24 rabbits were divided into 3 groups for study.Bone defect of 6 x 12 x 4 mm was made at the mandibular angle of rabbits and Sr-HAP of different proportion (10%,5%,0%) was applied to repair the defect. One group of animals were killed at 1 month, 3 months, 6 months to evaluate the biologic capacity with anatomy, tetracycline fluorescent marker and ration histology.

RESULTS

Sr-HAP almost hadn't been rejected by hosts, and early after operation the new bone in the Sr-HAP was found with great quantities as the degradation of Sr-HAP much more than that in the pure HA, and the difference of bone quantity can be shown in statistics. New bone in 5% Sr-HAP looked more mature than those in 10% Sr-HAP with no statistic difference in quantity. Strong and bright fluorescent rings can be seen around Sr-HAP from the 3 months to 6 months.

CONCLUSION

(1) Sr-HAP has a better biocompatibility, biodegradation than pure HA and an excellent osteoinductivity. (2) The ration of strontium isn't the key influencing the new bone quantity,total new bone quantity maybe associated with the degree of biodegradation. (3) The existence of Sr-HAP improves the total new bone quantity and prolongs the period of new bone increasing.

Glutathione depletion causes an uncoupling effect on retinal horizontal cells through oxidative stress

To investigate a physiological role of glutathione in the horizontal cells of carp retina, the gap junctional intercellular communication between horizontal cells was studied using the techniques of intracellular recording of light-induced responses and coupling of the fluorescence dye Lucifer Yellow. Intravitreal injection of 2.5 micromol L-buthionine sulfoximine, an inhibitor of glutathione synthesis, induced a dramatic reduction (20% of control) of retinal glutathione level two days after treatment. The low level of glutathione continued for a further four to five days, and thereafter gradually recovered to about 40% (20 days after injection) and 70% (50 days after injection) of the control level. The spatial properties of the photopic L-type horizontal cell response were examined by enlarging the diameter of the central spot and peripheral annulus over the recording point. In normal retinas, the response amplitude of horizontal cells was monotonically enhanced as the diameter of the spot increased (0.5-4.0 mm) and correspondingly the dye diffusion area was wide, as the injected Lucifer Yellow normally diffused to several neighboring cells. Treatment with L-buthionine sulfoximine significantly altered the spatial properties of horizontal cells by increasing the response amplitude to central spots and slightly decreasing that to peripheral annuli, which were observed by four days after injection. It also restricted intracellular Lucifer Yellow to one or two cells. Accompanying the recovery of the cellular level of glutathione, the spatial properties and dye coupling of horizontal cells were restored to normal. A time lag (two days) of initiation in retinal glutathione depletion and alteration of spatial or dye coupling properties of horizontal cells is discussed, together with reactive oxygen species accumulation.

Proliferative activity of calcifying odontogenic cysts as evaluated by proliferating cell nuclear antigen labeling index

The calcifying odontogenic cyst (COC) presents with diverse histological features; thus, several subclassifications have been proposed. To evaluate the significance of the various histological features and subtypes of COC from the perspective of proliferative activity, the proliferating cell nuclear antigen (PCNA) labeling index (LI; the percentage of positive nuclei) was assessed immunohistochemically in 25 cases of COC (21 benign and four malignant). All of the benign cases were of the cystic variety and further subclassified into non-proliferative subtype (NPS; four cases); proliferative subtype (PS; eight cases); and COC associated with odontoma (COCaO, nine cases). The PCNA LI of the malignant COC (65.2+/-5.6) was significantly higher than that of the benign COC (11.6+/-9.0; P = 0.002). Non-proliferative subtype (6.8+/-2.8) showed the lowest PCNA LI and PS (17.2+/-11.2) the highest of among the three subtypes of benign cystic COC (P = 0.028). In nine cases of COCaO, six showed epithelial lining of the non-proliferative type as NPS and the other three had lining with proliferative features as PS. The PCNA LI of the latter COCaO group (14.3+/-6.6) was significantly higher than that of the former (6.1+/-4.3; P = 0.05), as seen between PS and NPS. These results demonstrate that PCNA LI is a possible parameter for differentiating malignant COC from benign COC and, whatever the subtypes, the proliferative features in the lining are the main factor influencing the proliferating activity of COC.

A new model for heterotopic aortic valve transplantation

A new model for heterotopic aortic valve transplantation in the rat is described. A composite allograft with an intact aortic valve and partial mitral valve was harvested from 4-month-old (400-450 g) Long-Evans rats and grafted heterotopically into the abdominal aorta of 4-week-old (80-100 g) rats with an optimal size match. At the end of a 1-month observation period, all experimental animals were alive and all showed 100% patency of the aortic valve allografts on microscopic evaluation after death (n=40). Unlike previously used methods, the proposed model allows for the preservation of all three aortic valve cusps and a more remote placement of the anastomotic suture line from the aortic valve annulus. The use of younger recipient rats improves size match and amplifies allograft calcification. The purpose of this study was to provide an animal model to evaluate modalities of preservation and chemical treatment for aortic valves used as allografts or bioprosthesis.

Development and application of ultrasonic surgical instruments

In this paper, a new approach for designing ultrasonic surgical instruments (USI) is presented. These medical instruments convert an ultrasonic signal into a mechanical vibration by utilizing a magnetostrictive method and have been found to be very useful for various medical procedures. The implemented system consists of an ultrasonic generator, a transducer, and waveguide instruments. The generator produces a high-current ultrasonic signal. The transducer converts this signal into a mechanical vibration. By use of the waveguide instrument, the vibration can be propagated and amplified. This new type of USI possesses a comprehensive ability to stop bleeding, cut bone tissues, regulate frequency automatically, control temperature, etc. The results from animal experiments and from human clinical operations show that the developed USI has the advantages in various aspects over the conventional equipment.

Effects of Coriolus versicolor polysaccharides on superoxide dismutase activities in mice

AIM

To study if Coriolus versicolor polysaccharides (CVP) influence the superoxide dismutase (SOD) activities in mice.

METHODS

Normal, tumor-bearing, and radiated ICR mice were injected ip with CVP daily for 3-15 d. The SOD activity was assayed by epinephrine autoxidation test.

RESULTS

The SOD activities in lymphocytes and thymus were increased by CVP in both the normal mice with or without delayed hypersensitivity (DH). In tumor-bearing mice, CVP exerted not only inhibitory effects on tumor, growth and SOD activity in tumor tissue but also complete or partial restorative effects on the suppressed DH and on the declined SOD activities in lymphocytes, spleen, and thymus. The total SOD and manganese-containing SOD (MnSOD) activities in lymphocytes and thymus were dose-dependently enhanced by CVP (5-20 mg.kg-1) on d 3 after the tumor transplantation. In the mice exposed to 60Co (3 or 6 Gy), DH and SOD activities were dose-dependently decreased. These changes were completely or partly prevented by CVP.

CONCLUSION

CVP exerted the favorable effects on SOD activities in mice. Coriolus versicolor polysaccharides (CVP) exert inhibitory effects on experimental and clinical tumors. These effects are presumed to be mediated mainly by host-defence mechanism, especially immunological responeses. Superoxide dismutase (SOD) plays an important role in protecting cells against superoxide radical (O2-.) damages and over-production of O2-. or SOD abnormities exist in many diseases. The present study was to investigate if the CVP could exert some favorable effects on SOD activities in vivo.

[Study on treatment of infectious shock with recipe of liqi huoxue and kaibi gutuo]

Based on the pathogenesis of infectious shock which were stagnation of Qi, blood stasis, impairment of body resistance and trends to collapse, a series of new preparations of traditional Chinese Medicine was developed, Injection Kangjue Tongmai, Injection Yiqi Jiuyin and Injection Yiqi Huiyang, which could Liqi Huoxue and Kaibi Gutuo (regulate the flow of Qi, promote blood circulation, strengthen the body resistance and remit collapse), the result of 183 cases of infectious shock treated with them showed that the mortality was 4.37%, significantly lower than that of control group (23.0%). All three injections could rapidly elevate blood pressure and stabilize it for prolonged time, increase renal blood flow and lower blood viscosity. In animal experiment, the injections reduced lipid peroxide of vital organs, stabilized bio-membrane, protected the cell structure and maintained their normal functions.

The effects of alloplastic implant onlays on bone in the rabbit mandible

The relative importance of the factors that contribute to the bone erosion seen underlying alloplastic implants remains unknown. This study was designed to examine the effects of different alloplastic onlays on the mandible in a rabbit animal model. Three alloplastic materials (soft solid silicone, methyl methacrylate, and porous polyethylene) were examined to determine the importance of implant composition in bone resorption. Thin (1.5-mm) and thick (6-mm) onlays were used to determine the relative importance of implant thickness. Fluorescent markers were administered at different time intervals to evaluate the patterns of new bone formation. A total of 96 implants placed on the mandibles of 16 animals were examined grossly, histologically, and under fluorescent microscopy after 12 and 24 weeks. The frequency and degree of bone erosion were related both to the type of alloplast and to the thickness of the implant. Silicone implants were associated with the greatest amount of bone resorption (p < 0.01). Thicker silicone implants were associated with a greater degree of thinning (p < 0.05). Bone resorption beneath the implants was documented by the presence of osteoclasts actively eroding bone and by changes in the normal patterns of the fluorescent markers. Both the thin methyl methacrylate and the thin porous polyethylene implants had a low incidence of bone thinning. The thick methyl methacrylate implants caused more erosion than the thin implants of the same material, although this was less than the silicone groups. Increasing the thickness of porous polyethylene implants did not adversely affect the underlying bone.(ABSTRACT TRUNCATED AT 250 WORDS)

Bovine glomerular amyloidosis: morphological studies

Bovine kidney material with advanced glomerular deposits of amyloid was studied immunohistochemically using the avidin biotin complex immunoperoxidase method, with rabbit anti-horse AA serum as primary antibody. Severely affected glomeruli consisted of strongly reacting positive material, obscuring all cellular structures. Transmission electron microscopy revealed that the amyloidotic areas, with evident amyloid fibrils, also contained a considerable admixture of cellular remnants. In this investigation it was found that such material was more abundant in the bovine glomerular amyloid masses than in amyloid laden organs from other animal species, and it is discussed to what extent this observation may explain the varying tinctorial properties of amyloid deposits in bovine tissues, and the relative high content of histones in bovine amyloid proteins.

Comparison of various delivery systems for demineralized bone matrix in a rat cranial defect model

Demineralized bone matrix (DBM) has been successfully used as a substitute for bone grafting. Autogenous bone grafts may cause site morbidity and undergo significant resorption. DBM may overcome these problems, but it has no mechanical stability until bone formation has occurred. We tested various alloplastic implants (i.e., Surgicel, polydioxanone [PDS], porous polyethylene [Medpor], and Gelfoam) in combination with DBM and compared it with DBM alone in a 9 x 9 mm rat cranial defect model. Histological and biomechanical measurements were performed at postoperative month 2. Among the study groups, Gelfoam/DBM inhibited bone formation to varying degrees and was the only group that displayed an inflammatory response. Mechanical pushout tests using a servohydraulic testing frame were conducted. The Medpor/DBM implant displayed the strongest support at 2 months; maximum load was 95% of intact skull. Surgicel/DBM and DBM alone were comparable; maximum load was 66% of intact skull. Gelfoam/DBM and PDS/DBM displayed the weakest support (48% of intact skull). We conclude that, after 2 months of implantation, alloplastic/DBM composites provide osseous structural integration. Gelfoam/DBM is not an effective delivery system for DBM in our model.

Structure of a novel disulfide of 2-(N-acetylcysteinyl)amido-2-deoxy-alpha-D-glucopyranosyl-myo-inositol produced by Streptomyces sp

A novel dimer of an inositol glycoside was isolated from the mycelial extracts of Streptomyces sp. AJ 9463. Its structure was assigned as a disulfide of 2-(N-acetyl-L-cysteinyl)amido-2-deoxy-alpha-D-glucopyranosyl-(1-->1)-1D- myo- inositol (1).

Ultrasound debridement of trabeculated bone: effective and atraumatic

Given the plethora of techniques available for debridement of contaminated bone, no single method can be considered ideal. Ultrasound has been shown to be less traumatic and more effective for debridement of contaminated soft tissue than either abrasive scrubbing or high-pressure jet irrigation. Using the distal femur and condyle of 23 freshly sacrificed adult Sprague-Dawley rats, this study was undertaken to compare ultrasonication to traditional debridement techniques in (1) their effectiveness in decontaminating trabeculated bone, (2) the subsequent effect of each treatment on bone cell function as measured by protein synthesis, and (3) the direct mechanical effects of each technique on the integrity of the bone structure itself. Ultrasonic debridement was found to be as effective as high-pressure jet irrigation or surgical scrubbing in debridement of contaminated trabeculated bone (no significant statistical difference). Overall activated bone cell function 24 hours after each debridement technique also was found to be equivalent (no significant statistical difference). However, electron microscopy reveals radical structural alterations of the bone after high-pressure jet irrigation or abrasive scrubbing that are not seen with ultrasound debridement. Acutely, the devastating effects of abrasive scrubbing and high-pressure jet irrigation leave an exposed bone matrix not only devoid of any cells but also honeycombed with interstices for entrapment of bacteria and other contaminants. All three debridement methods leave the deeper bone cells viable, but only ultrasound maintains the integrity of the directly involved bone trabeculum to reduce contamination, prevent colonization, and decrease possible infection.

Evaluation of a temporary arteriovenous shunt to establish neovascularization in a musculocutaneous flap: an experimental study

On the dorsum of adult Sprague-Dawley rats, 3 x 7 cm pedicle flaps were raised and a temporary arteriovenous shunt (AVS) from anastomosis of the tail artery and vein was placed beneath. Fourteen, 21 and 28 days later, the pedicle flaps were converted to island flaps leaving only the AVS attachment. The degree of subsequent flap viability was directly related to the amount of time before flap conversion. At 14, 21 and 28 day intervals, there was 33.4%, 73.5% and 98% flap viability, respectively. Long-term AVS patency was found not to be required for flap survival. Normal hair growth, quantity and quality, occurred in only the 28 day delay group. Microangiography and histologic examination revealed extensive neovascularization from both the AVS artery and vein extending into the muscle, subcutaneous tissue and skin layers of each island flap. In summary, neovascularization of a large random pattern musculocutaneous island flap is possible using a temporary arteriovenous shunt. Flap survival is directly related to the length of time between AVS placement and cutaneous pedicle division, although long-term AVS patency is not required for continued flap viability. Hair growth may directly reflect the degree of underlying neovascular maturation. This AVS neovascularization technique could be applied to create new donor sites for free tissue transfer.

[Fibrous dysplasia of jaw and facial bones:A combined analysis of clinic,radiologic and histopathologic diagnosis of 117 cases]

A clinical-radiologic-histopathologic review of 106 cases of fibrous dysplasia involving the jaws is presented. Ninety eight patients onset in the first and second decades.Fifteen cases were polyostotic and the remaining cases were were monstotic.Radiologicaly,the lesions showed and extending growth pattern,poor definite border and slight pattern,poor definite border and slight involvement of teeth.The radiographic features were classified into four types:ground grass (52.0%),sclerotic(8.0%),cystic-like(8.0%) and mixed type (32.0%).Histologically the lesions were characterized by a cellular fibrous stroma that contain varying amounts of mineralized substance,represented by woven bone(63.0%),lamellar bone(30.0%) and cementum-like structure(7.0%).The final definitive diagnosis requires the combined evaluation of clinic,radiologic and histopathologic findings.

Biosynthetic studies of allosamidin. 2. Isolation of didemethylallosamidin, and conversion experiments of 14C-labeled demethylallosamidin, didemethylallosamidin and their related compounds

A new allosamidin analog, termed didemethylallosamidin (3), was isolated from the mycelia of Streptomyces sp. AJ 9463 which is a producer of allosamidin (1) and demethylallosamidin (2). 14C-Labeled 1, 2 and 3 as well as their related compounds, 4, 5, and 6, were prepared to investigate the biosynthesis of 1. Conversion experiments with the labeled allosamidins revealed that 2 was a precursor of 1, but 3 was not incorporated. This suggests that the first N-methyl group is introduced before the cyclization of the aminooxazoline ring during the biosynthesis of 1. Although none of the compounds 4, 5, and 6 were converted to 1, the production of 1 was inhibited by the addition of 4.