Direct splitting of water under visible light irradiation with an oxide semiconductor photocatalyst

The photocatalytic splitting of water into hydrogen and oxygen using solar energy is a potentially clean and renewable source for hydrogen fuel. The first photocatalysts suitable for water splitting, or for activating hydrogen production from carbohydrate compounds made by plants from water and carbon dioxide, were developed several decades ago. But these catalysts operate with ultraviolet light, which accounts for only 4% of the incoming solar energy and thus renders the overall process impractical. For this reason, considerable efforts have been invested in developing photocatalysts capable of using the less energetic but more abundant visible light, which accounts for about 43% of the incoming solar energy. However, systems that are sufficiently stable and efficient for practical use have not yet been realized. Here we show that doping of indium-tantalum-oxide with nickel yields a series of photocatalysts, In(1-x)Ni(x)TaO(4) (x = 0-0.2), which induces direct splitting of water into stoichiometric amounts of oxygen and hydrogen under visible light irradiation with a quantum yield of about 0.66%. Our findings suggest that the use of solar energy for photocatalytic water splitting might provide a viable source for 'clean' hydrogen fuel, once the catalytic efficiency of the semiconductor system has been improved by increasing its surface area and suitable modifications of the surface sites.

[Relationship between cholinesterase, prothrombin activity and albumin and the pathology of the liver]

BACKGROUND

To investigate the relationship between serum cholinesterase, albumin and plasma prothrombin activity and the pathology of the liver in patients with viral hepatitis.

METHODS

Totally 135 patients diagnosed as chronic hepatitis, cirrhosis and/or severe hepatitis with needle biopsy of liver were enrolled in this study. Serum cholinesterase and albumin of the patients were detected with enzyme rate method; meanwhile, their plasma prothrombin activity was detected with turbidimetry test.

RESULTS

The percentage of decrease of the level of serum cholinesterase was higher than that of albumin and plasma prothrombin activity in chronic mild and moderate hepatitis; the level of serum cholinesterase, albumin and plasma prothrombin activity decreased gradually followed by the exacerbation of inflammatory reaction (P<0.001) and by the elevation of degree of fibrosis of the liver (P <0.001) their correlation coefficient was 0.720 to 0.778 (P<0.001).

CONCLUSION

The level of serum cholinesterase could better a nd more sensitively reflect the synthetic function and the damage of the pathology of the liver than that of albumin and plasma prothrombin activity could do, they all negatively correlated with the pathology of the liver.

Genetic tracing reveals a stereotyped sensory map in the olfactory cortex

The olfactory system translates myriad chemical structures into diverse odour perceptions. To gain insight into how this is accomplished, we prepared mice that coexpressed a transneuronal tracer with only one of about 1,000 different odorant receptors. The tracer travelled from nasal neurons expressing that receptor to the olfactory bulb and then to the olfactory cortex, allowing visualization of cortical neurons that receive input from a particular odorant receptor. These studies revealed a stereotyped sensory map in the olfactory cortex in which signals from a particular receptor are targeted to specific clusters of neurons. Inputs from different receptors overlap spatially and could be combined in single neurons, potentially allowing for an integration of the components of an odorant's combinatorial receptor code. Signals from the same receptor are targeted to multiple olfactory cortical areas, permitting the parallel, and perhaps differential, processing of inputs from a single receptor before delivery to the neocortex and limbic system.

[Radiographic study of the development of the permanent teeth]

OBJECTIVE

To study the development of permanent teeth by radiographic methods.

METHODS

The permanent teeth development of children ranging from 4-17 years was evaluated from 1709 panoramic radiographs by the Nolla's method. Each tooth was graded from 0 to 10 stage. The average developmental stage for girls and boys were calculated.

RESULTS

The average developmental stage and development curves for girls and boys were obtained respectively. For the completion of crown and root development, girls are more advanced than boys by an average of 0.3 and 0.6 years.

CONCLUSIONS

Girls are ahead of boys for the development of the permanent teeth. The norms of the maturation of permanent teeth can be used to evaluated the development of the individual teeth.

A study of titanium nitride diffusion barriers between aluminum and silicon by X-ray absorption spectroscopy: the Si, Ti and N results

We report a multi-elment, multi-edge and multi-detection mode X-ray photoabsorption study of a series of Al/TiN(x)/Si(100) thin films as a function of the TiN(x) film thickness (100A-500A) and of the annealing temperature (400 degrees C-600 degrees C). The Si K- and L-edge results show that Si does not diffuse to the surface for all the films. The high resolution Ti L-edge and N K-edge spectra show that the TiN(x) layer undergoes a dramatic chemical reaction with the gradual increase in the annealing temperature. This chemical reaction stabilizes at 560 degrees C at which the TiN(x) film is known to fail to act as an effective diffusion barrier between Al and Si.

Structure and chromosomal localization of the RAE28/HPH1 gene, a human homologue of the polyhomeotic gene

The Polycomb group of (Pc-G) genes and trithorax group of genes are known to play a crucial role in the maintenance of the transcriptional repression state of Hox genes, probably through modification of the chromatin configuration. The rae28/mph1 gene is a mammalian homologue of the Drosophila polyhomeotic gene, which belongs to the Pc-G genes. As reported previously, we established mice deficient in the rae28/mph1 gene and showed that these homozygous animals displayed the developmental defects compatible with a human congenital disorder, CATCH22 syndrome. In this study we analyzed the structural organization of the human counterpart of the rae28/mph1 gene (RAE28/HPH1) and its processed pseudogene (psiPH), which are located on, respectively, human chromosome 12p13 and 12q13. The HPH1 gene consists of 15 exons spanning approximately 26 kb and its structural organization is well conserved between mouse and human. These genetic information of the RAE28/HPH1 gene may provide an important clue for further examination of its involvement in human congenital disorders related to CATCH22 syndrome.

[Study on change of SCC Ag, CEA and CA15-3 in rat model of lung squamous cell carcinoma]

BACKGROUND

To evaluate significance of squamous cell carcinoma associated antigen (SCC Ag) and carcinoembrynoic antigen (CEA) and carbohydrate antigen 15-3 (CA15-3) in early diagnosis of lung squamous cell carcinoma

METHODS

Lung squamous cell carcinoma was induced with methylcholanthrene (MCA) in iodized oil in Wistar rats. Ninty-one rats were used for this experiment, and the rats were sacrificed on the 20th, 40th, 50th, 60th, 70th and 80th days respectively. The stage of the cancer development including atypical hyperplasia, carcinoma in situ, early invasive carcinoma was diagnosed histopathologically. SCC Ag, CEA and CA15-3 in the serum of different conceration stage rats were measured by MEIA technique.

RESULTS

Serum levels of SCC Ag, CEA and CA15-3 of the model rats in the atypical hyperplasia and carcinoma in situ had no significant difference. The level of SCC Ag increased predominantly at the early invasive carcinoma(P<0.01), but the other two markers had no change.

CONCLUSIONS

SCC Ag level in serum may be of considerable importance in the early diagnosis of lung squamous cell carcinoma.

PSGR, a novel prostate-specific gene with homology to a G protein-coupled receptor, is overexpressed in prostate cancer

PSGR, a new prostate tissue-specific gene with homology to the G protein-coupled odorant receptor gene family, has been identified. Here we report the characteristics of the predicted protein sequence of PSGR and its prostate tissue specificity and expression profile in human prostate cancer and matched normal tissues. Using multiple tissue Northern blots from over 50 different tissues, PSGR expression was restricted to human prostate tissues. Paired normal and tumor specimens from 52 primary prostate cancers, obtained by laser capture microdissection or manual microdissection, were analyzed for PSGR expression by semiquantitative and real-time PCR assays. The differential expression of PSGR between normal and tumor tissues was highly significant (P < 0.001), and 32 of 52 (62%) matched prostate specimens exhibited tumor-associated overexpression of PSGR. Of note, there was very little or no expression of PSGR in many normal specimens in comparison with the generally high expression of PSGR seen in matched tumor specimens. In situ hybridization assays showed restricted PSGR expression in the epithelial cells of the normal and tumor tissue sections. Restricted expression of PSGR in prostatic epithelial cells, overexpression of the PSGR in a significant percentage of prostate cancers, and the predicted protein sequence of PSGR with seven transmembrane domains provide a foundation for future studies evaluating the potential of PSGR as a prostate cancer gene expression marker and the utility of PSGR protein as a novel target for developing immunotherapeutic strategies for prostate cancer.

PCGEM1, a prostate-specific gene, is overexpressed in prostate cancer

A prostate-specific gene, PCGEM1, was identified by differential display analysis of paired normal and prostate cancer tissues. Multiple tissue Northern blot analysis revealed that PCGEM1 was expressed exclusively in human prostate tissue. Analysis of PCGEM1 expression in matched normal and primary tumor specimens revealed tumor-associated overexpression in 84% of patients with prostate cancer by in situ hybridization assay and in 56% of patients by reverse transcription-PCR assay. Among various prostate cancer cell lines analyzed, PCGEM1 expression was detected only in the androgen receptor-positive cell line LNCaP. Extensive DNA sequence analysis of the PCGEM1 cDNA and genomic DNA revealed that PCGEM1 lacks protein-coding capacity and suggests that it may belong to an emerging class of noncoding RNAs, also called "riboregulators." The PCGEM1 locus was mapped to chromosome 2q32. Taken together, the remarkable prostate-tissue specificity and androgen-dependent expression of PCGEM1 as well as its elevated expression in a significant percentage of tumor tissues suggest specific functions of PCGEM1 in the biology and tumorigenesis of the prostate gland.

p53-dependent induction of heat shock protein 27 (HSP27) expression

Transcriptional activation of the p53 target genes plays a critical role in the cellular response to DNA damage, hypoxia, cellular stress and other signals regulating the cell cycle and apoptosis. The discovery of new p53 target genes continues to reveal novel mechanisms of action of this multifaceted protein. We used cDNA arrays to search for p53-regulated genes in prostate cancer cells. In this report, we describe robust induction of heat shock protein 27 (hsp27) in prostate cancer cells (DU145, LNCaP, PC3) following wild-type p53 expression from an adenoviral p53 expression vector (AdWTp53). A mutant p53 (R175H)-containing adenoviral expression vector did not induce hsp27. hsp27 expression was not altered in prostate cancer cells following expression of cyclin-dependent kinase inhibitors: p21(waf1/cip1) and p27(kip1) from adenoviral expression vectors. Treatment of cells with staurosporine, an apoptosis-inducing agent, did no affect hsp27 expression. These observations provide evidence that induction of hsp27 expression was wild-type p53-specific and was not due to non-specific effects of cell growth arrest and/or apoptosis. Previous studies and the experiment reported here show induction of hsp27 expression in response to androgen ablation, a physiological state that induces apoptosis in prostatic epithelial cells. The nature of p53 and hsp27 interactions in the regulation of apoptosis and/or cell growth needs to be further defined.

p53 regulates the expression of the tumor suppressor gene maspin

Maspin has been shown to inhibit tumor cell invasion and metastasis in breast tumor cells. Maspin expression was detected in normal breast and prostate epithelial cells, whereas tumor cells exhibited reduced or no expression. However, the regulatory mechanism of maspin expression remains unknown. We report here a rapid and robust induction of maspin expression in prostate cancer cells (LNCaP, DU145, and PC3) and breast tumor cells (MCF7) following wild type p53 expression from an adenovirus p53 expression vector (AdWTp53). p53 activates the maspin promoter by binding directly to the p53 consensus-binding site present in the maspin promoter. DNA-damaging agents and cytotoxic drugs induced endogenous maspin expression in cells containing the wild type p53. Maspin expression was refractory to the DNA-damaging agents in cells containing mutant p53. These results, combined with recent studies of the tumor metastasis suppressor gene KAI1 and plasminogen activator inhibitor 1 (PAI1), define a new category of molecular targets of p53 that have the potential to negatively regulate tumor invasion and/or metastasis.

In vivo analysis of plastid psbA, rbcL and rpl32 UTR elements by chloroplast transformation: tobacco plastid gene expression is controlled by modulation of transcript levels and translation efficiency

5' and 3' untranslated regions (UTRs) of plastid RNAs act as regulatory elements for post-transcriptional control of gene expression. Polyethylene glycol-mediated plastid transformation with UTR-GUS reporter gene fusions was used to study the function of the psbA, rbcL and rpl32 UTRs in vivo. All gene fusions were expressed from the same promoter, i.e. the promoter of the 16S-rRNA gene, such that variations in RNA and protein levels would be due to the involved UTR elements alone. Transgenic tobacco lines containing different combinations of UTRs showed fivefold variation in the uidA-mRNA level (RNA stability) and approximately 100-fold differences in GUS activity, a measure of translation activity. The rbcL 5'-UTR conferred greater mRNA stability than the psbA 5'-UTR on uidA transcripts. In contrast, the psbA 5'-UTR enhanced translation of GUS to a much greater extent compared to the rbcL 5'-UTR. The psbA 5'-UTR also mediated light-induced activation of translation which was not observed with other constructs. Deletion mutagenesis of an unanalysed terminal sequence element of the psbA 5'-UTR resulted in a twofold drop in uidA-mRNA level and a fourfold decrease in translation efficiency. Exchange of 3'-UTRs results in up to fivefold changes of mRNA levels and does not significantly influence translation efficiency. The mechanical impacts of these results on plastid translation regulation are discussed.

[The effect of pressure on the morphology of superior mesenteric vein in rabbits]

The effect of pressure on the morphology of the superior mesenteric vein of rabbits (SMV) was researched with the method of constant pressure fixation. The results indicate the morphology of SMV is similar to human umbilical cord vein. It looks like the structure of femoral artery of vein in many ways. Under constant pressure fixation (4 kPa), the internal elastic membrane of SMV is straightened, and the wall of SMV becomes thin, with its media thinning from 51.680 microns to 32.3260 microns. The long diameter of nucleus of the smooth muscles decreases from 1.9146 microns to 3.4980 microns, the short diameter of nucleus of the smooth muscles becomes from 0.7884 micron to 0.5228 micron. The direction of the tension on the smooth muscles is mainly longitudinal.

[Experimental study of parotid gland injected with gentian violet]

OBJECTIVE

The Gentian Violet was used for treating the chronic parotitis since 1960's, but the dosage and the histologic changes of the tissues were undefined until now. We try to study the histologic changes of the salivary glands, heart, liver and kidneys after large volume of gentian violet was injected into the parotid gland through the duct.

METHODS

5 ml of Gentian Violet was injected to each side of 6 dogs. The macropathologic and histologic examination of the salivary glands, heart, liver and kidneys were performed at 30 min, 60 min, 120 min, 21 days and 9 months separately after the perfusion.

RESULTS

Local swelling was obvious in two or three days after infusion and subsided in one week in most of the dogs. Degeneration of the gland took place after 20 days. After 9 months, the parotid gland tissues were replaced by the connective tissues. On the other hand, no histologic change was observed in heart, liver and kidney in the investigation.

CONCLUSION

The Gentian Violet can cause degeneration of the parotid gland including the duct and replaced by connective tissues later. There is no obvious changes were noted in other organs.

[Subclinical Sjögren's syndrome]

OBJECTIVE

To investigate various manifestations and treatment of subclinical Sjögren's syndrome (SS).

METHODS

A long term clinical, laboratory and sialographic observations were performed in 24 patients with subclinical SS. Injectin of thymosin intramusularly was used to treat the patients and clinical effect of this treatment was evaluated.

RESULTS

All of 24 cases had experienced recurrent parotid swellings (RPS) for 2-17 years (mean 7 years) before dry mouth and dry eyes occurred and all of them were misdiagnosed as chronic suppurative parotitis or sialadenitis. Follow-up showed that all of these patients developed SS. Vasculitis was found in 8 cases, purpura in 2 cases. The vascular involvement was relatively common in subclinical SS. Main sialographic findings was sialectasis of terminal ducts with irregular dilation of main duct. Frequency of RPS was markedly decreased in the patients treated with thymosin.

CONCLUSION

The proposal of subclinical SS has theoretical value for understanding the entity and reclassification of chronic suppurative parotitis, and has guide value for diagnosis and treatment of SS in the early stage. Injection of thymosin is considered an effective therapy to reduce RPS in subclinical SS.

[The effect of activity of smooth muscles on the relationship of circumferential stress-strain of superior mesenteric veins in rabbits]

The superior mesenteric veins (SMV) of 14 rabbits were divided into two groups for experiment of inflation pressure, namely the normal group and the inactivated smooth muscles group. The results showed that the relationship of circumferential stress-strain of SMV could be expressed with the exponential equation. Constant X2 is effected by the active condition of smooth muscles. The difference of the material constant X2 between the two groups was statistically significant (P < 0.05), but the difference of the material constant X1 between the two groups was not statistically significant (P > 0.05). These suggest that X2 is the parameter concerning the activity of smooth muscles.

[Purification of recombinant erythropoietin by reversed-phase high performance liquid chromatography (RP-HPLC)]

Recombinant erythropoietin is a glycoprotein which is strongly hydrophobic. We purified recombinant erythropoietin by RP-HPLC. The results showed that 30 nm Spherisorb C4 reversed-phase column and acetonitrile-TFA mobile phase with gradient elution, could readily isolate recombinant erythropoietin from crude samples with high speed and efficiency. Erythropoietin could be eluted at the concentration of about 50% acetonitrile with appropriate sample purity and elution gradient. When RP-HPLC is used as a final step of purification, the purity of sample should be at least 60%. The purity of the product tested by SDS-PAGE was nearly 100%. And the specific activity of the product was about 1.96 x 10(3) IU/g protein.

Zonal and regional differences identified from precision mapping of vitamin A-storing lipid droplets of the hepatic stellate cells in pig liver: a novel concept of addressing the intralobular area of heterogeneity

Knowledge of hepatic heterogeneity has been strikingly increased, while an accurate means for addressing intralobular positions is still lacking. We examined pig liver preparations of the gold impregnation method for vitamin A-storing lipid droplets in hepatic stellate cells. Droplet morphometry was performed under oil immersion, and the calculated volumes plotted on computerized maps. The heterogeneous results were assessed with five concentric zones and five radial regions; the latter were determined based on midseptum visualized by portal injection. Zonation and regionation thus subdivided lobules into 5-zone/5-region (5Z/5R) compartmentalization. Distribution of values exhibited a distinct zonal gradient, heightened at peripheral zones 1 and 2, decreased over intermediate zone 3 toward centrilobular zones 4 and 5; peak was always found at zone 2. Within a single zone, variations were obvious, forming a regional gradient. Values were significantly higher at periportal than midseptal regions. Digitized mapping showed that low values filled up centrilobular zones, whereas high values concentrated in periportal regions. Along the periphery, inlet venules were quantified, revealing an occurrence rate of 60% at periportal, and 5% at midseptal regions, closely compatible with the regional gradient of vitamin A-storing capacity. The interweaving between zonal and regional gradients results in a vitamin A-low territory, a compound area composed of centrilobular zones plus extensions into midseptal regions. Because the results could account for physiological and pathological events, we regard the 5Z/5R compartmentalization a model worth routine adoption for a precise description of any morphofunctionally demonstrable heterogeneity of the liver lobules.

t(8;20)(q22;p13): a novel variant translocation of t(8;21) in acute myeloblastic leukaemia

A novel variant translocation t(8;20)(q22;p13) detected by karyotype analysis of bone marrow cells using R- and G-banding techniques, is reported in a case of M2-acute myeloid leukaemia (AML). The leukaemic cells were indistinguishable morphologically from that of M2-AML with t(8;21)translocation. RT-PCR revealed no AML1/ETO fusion transcript, but the wild-type ETO-3' was expressed in the bone marrow cells suggesting that t(8;20) is a true simple variant translocation of t(8;21), and that a fusion gene consisting of ETO and an unidentified gene located in band 20p13 may exist in our case. Further study is required to clarify the entity of the assumed fusion gene.

[Clinical and pathological study on liver fibrosis in viral hepatitis]

49 patients with viral hepatitis were studied on the correlationship between liver fibrosis and the level of serum precollagen type III (PC III), pre-collagen III pre-peptide (P III P), Laminin (LN), hyaluronic acid (HA) and collagen type IV (IV-C), as well as relationship between them and the expression of LN, IV-C, a-smooth muscle actin (a-SMA) and cytokeration (CK) in the liver tissues examined by immunohistochemistry. Results showed that the level of PC III, P III P, LN, HA and IV-C in the groups of liver cirrhosis and chronic severe hepatitis were higher than that in the groups of acute and chronic hepatitis. High correlation was found between the level of these markers (especially the level of the IV-C) and the degree of fibrosis in the group of chronic hepatitis. So were the expression of LN, IV-C, a-SMA and CK in the liver tissue. The results also showed that the liver fibrosis correlated with inflammatory reaction in the liver. So the authors suggested that more attention should be paid to the inflammatory reaction of the liver for prevention and treatment of liver fibrosis.

Repair effect of phenylpropanoid glycosides on thymine radical anion induced by pulse radiolysis

Repair effects on thymine radical anion by six phenylpropanoid glycosides (PPGs), isolated from Pedicularis species, were studied using pulse radiolysis method. The thymine radical anion was produced by the reaction of hydrated electron with thymine. PPGs were added into the thymine solution saturated with N(2). Kinetic analysis showed that transient absorption spectrum of thymine radical anion formed at first, and then after several microseconds of pulse radiolysis changed to that of PPG radical anion. The evidence indicated that thymine radical anion was repaired through one-electron transfer between the radical anion and PPG. Electrophilic phenyl-substituted unsaturated carboxylic group containing in PPGs' structure was able to capture electron from thymine radical anion before it undergo reversible protonation. The reaction rate constants of electron transfer from thymine radical anion to PPGs were within 1.16-2.29 x 10(9) dm(3) mol(-1) s(-1).