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The mammalian retina is a tractable model system for analyzing transcriptional networks that guide neural development. Spalt family zinc-finger transcription factors play a crucial role in photoreceptor specification in Drosophila, but their role in mammalian retinal development has not been investigated. In this study, we show that that the spalt homolog Sall3 is prominently expressed in developing cone photoreceptors and horizontal interneurons of the mouse retina and in a subset of cone bipolar cells. We find that Sall3 is both necessary and sufficient to activate the expression of multiple cone-specific genes, and that Sall3 protein is selectively bound to the promoter regions of these genes. Notably, Sall3 shows more prominent expression in short wavelength-sensitive cones than in medium wavelength-sensitive cones, and that Sall3 selectively activates expression of the short but not the medium wavelength-sensitive cone opsin gene. We further observe that Sall3 regulates the differentiation of horizontal interneurons, which form direct synaptic contacts with cone photoreceptors. Loss of function of Sall3 eliminates expression of the horizontal cell-specific transcription factor Lhx1, resulting in a radial displacement of horizontal cells that partially phenocopies the loss of function of Lhx1. These findings not only demonstrate that Spalt family transcription factors play a conserved role in regulating photoreceptor development in insects and mammals, but also identify Sall3 as a factor that regulates terminal differentiation of both cone photoreceptors and their postsynaptic partners.

Objective: To study an intervention model of "schools without infected students with schistosoma japonica", to control and prevent students from schistosoma infection., Methods: Twelve primary schools of four heavy endemic counties (districts) with schistosomiasis in the Poyang Lake areas were selected as the study fields, of which, ten schools were the experimental groups, and the other two schools were the control groups by cluster random sampling. All enrolment students were the target population. The baseline survey was carried out in 2005, and an intervention model, "information dissemination + behavior participation + behavior encouragement", was applied in the experiment groups in 2006 - 2008, then the effect of intervention was assessed., Results: Before intervention (2005), the anti-schistosomiasis knowledge awareness rate of experimental and control groups were 14.75% (324/2196) and 16.58% (91/549), and the different was not significant (χ(2) = 1.14, P > 0.05); the rate of accurate attitude of anti-schistosomiasis were 14.71% (323/2196) and 11.84% (65/549) in experimental and control groups, and the difference was not significant (χ(2) = 2.98, P > 0.05); the rate of contacting infected water were 15.44% (18 988/122 976) and 15.03% (4622/30 744) in experimental and control group and the difference was not significant (χ(2) = 3.13, P > 0.05); and the infection rate of schistosomiasis of experiment control groups were 9.65% (212/2196) and 10.56% (58/549), the difference was not significant (χ(2) = 0.41, P > 0.05). After one year intervention (2006), the anti-schistosomiasis knowledge awareness rate of experimental and control groups were 97.79% (2032/2078) and 18.11% (98/541), and the different was significant (χ(2) = 1794.31, P < 0.01); the rate of accurate attitude of anti-schistosomiasis were 99.09% (2059/2078) and 13.49% (73/541) in experimental and control group, and the difference was significant (χ(2) = 2077.45, P < 0.01). After 1 - 3 years intervention (2006 - 2008), there were no any contactors with infected water and infectors with schistosome in students of the experiment group in successive 3 years. While in the control group of the same period, the rate contacting infected water were 16.12% (4884/30 296), 11.11% (3079/27 720) and 12.25% (3451/28 168); the infection rate of schistosomiasis were 8.87% (48/541), 7.47% (37/495) and 7.95% (40/503), respectively., Conclusion: The intervention model of health promotion, "information dissemination + behavior participation + behavior encouragement", can effectively control and prevent students from infecting schistosoma japonica in heavy endemic areas with schistosomiasis.

Selective expression of retinal cone opsin genes is essential for color vision, but the mechanism mediating this process is poorly understood. Both vertebrate rod and medium wavelength-sensitive (M) cone photoreceptors differentiate by repression of a short wavelength-sensitive (S) cone differentiation program. We found that Pias3 acts in mouse cone photoreceptors to activate expression of M opsin and repress expression of S opsin, with the transcription factors Trbeta2 and Rxrgamma mediating preferential expression of Pias3 in M cones. Finally, we observed that Pias3 directly regulated M and S cone opsin expression by modulating the cone-enriched transcription factors Rxrgamma, Roralpha and Trbeta1. Our results indicate that Pias3-dependent SUMOylation of photoreceptor-specific transcription factors is a common mechanism that controls both rod and cone photoreceptor subtype specification, regulating distinct molecular targets in the two cell types.

Mutation of rod photoreceptor-enriched transcription factors is a major cause of inherited blindness. We identified the orphan nuclear hormone receptor estrogen-related receptor beta (ERRbeta) as selectively expressed in rod photoreceptors. Overexpression of ERRbeta induces expression of rod-specific genes in retinas of wild-type as well as Nrl(-/-) mice, which lack rod photoreceptors. Mutation of ERRbeta results in dysfunction and degeneration of rods, whereas inverse agonists of ERRbeta trigger rapid rod degeneration, which is rescued by constitutively active mutants of ERRbeta. ERRbeta coordinates expression of multiple genes that are rate-limiting regulators of ATP generation and consumption in photoreceptors. Furthermore, enhancing ERRbeta activity rescues photoreceptor defects that result from loss of the photoreceptor-specific transcription factor Crx. Our findings demonstrate that ERRbeta is a critical regulator of rod photoreceptor function and survival, and suggest that ERRbeta agonists may be useful in the treatment of certain retinal dystrophies.

Allophycocyanin (APC) was purified from Spirulina platensis using hydroxylapatite chromatography and ion-exchange chromatography. Effects of solution pH on spectra of APC were studied. APC has an absorption maximum at 650 nm, and a shoulder at 620 nm. The fluorescence emission peak is at 660 nm. The efficiency of energy absorbing and transfer in APC could be reflected by the absorption spectra and fluorescence spectra, respectively. Structural variations of APC could be monitored by means of circular dichroism spectra. APC showed good absorbance and fluorescence stability at varying pH with only minor changes between pH 4-10. The trimeric structure of APC was maintained while local variations of protein peptides were allowed in response to the environmental disturbance. Beyond this pH range, secondary structure as well as overall conformation of APC dramatically changed, and the energy absorption and transfer ability were also disrupted.

Background: There are racial differences in the prevalence and types of androgenetic alopecia (AGA). The prevalence of AGA has been studied in Caucasians and in some Asian people. In China, although there have been some epidemiological studies carried out in single cities or regions, no multicentre population-based study has been reported., Objectives: To study the prevalence and types of AGA in China and to compare the results with those previously reported in Caucasians and in other Asian people., Methods: A community-based study was carried out in six cities of China. Subjects were interviewed face-to-face and completed questionnaires. The degree of AGA was classified according to the Norwood and Ludwig classifications., Results: In total 17 886 subjects were interviewed and 15 257 completed the questionnaires. In men, the overall prevalence of AGA was 21.3%, with 2.8% in men aged 18-29 years, 13.3% in those aged 30-39 years, 21.4% in those aged 40-49 years, 31.9% in those aged 50-59 years, 36.2% in those aged 60-69 years and 41.4% in those aged 70 years and over. The most common type was frontal and vertex hair loss. A small number of subjects (3.7%) showed 'female pattern' hair loss. In women, the prevalence of AGA was 6.0%, with 1.3% in women aged 18-29 years, 2.3% in those aged 30-39 years, 5.4% in those aged 40-49 years, 7.5% in those aged 50-59 years, 10.3% in those aged 60-69 years and 11.8% in those aged 70 years and over. Ludwig grade I was the most common type. The prevalence of AGA varied between cities. A positive family history was present in 29.7% of men and 19.2% of women with AGA., Conclusions: The prevalence of AGA in Chinese men and women was lower than in Caucasians and similar to that in Koreans.

Microneme protein 8 (MIC8) is considered a new essential invasion factor in Toxoplasma gondii. In the present study, a deoxyribonucleic acid vaccine expressing MIC8 of T. gondii was constructed and the immune response it induced in Kunming mice was evaluated. The gene sequence encoding MIC8 was inserted into the eukaryotic expression vector pVAX I, and the pVAX-MIC8 expression plasmid was constructed, and the plasmid diluted with PBS to 100 mg/100 microl was injected into the Kunming mice muscularly. Levels of IgG antibody, gamma-interferon (IFN-gamma), interleukin-2 (IL-2), interleukin-4, and interleukin-10 were detected. The mice were challenged with tachyzoites of the virulent T. gondii RH strain at the 14th day after the last immunization to observe the survival time. The high level of IFN-gamma, IL-2, and IgG antibody indicated that mice vaccinated with recombinant pVAX-MIC8 plasmid could elicit strong cellular and humoral immune responses and showed a significantly increased survival time (10.3 +/- 0.9 days) compared with control mice which died within 5 days of challenge infection. These data demonstrate that the T. gondii MIC8 is a potential vaccine candidate against toxoplasmosis.

Infection with the intracellular protozoan parasite Toxoplasma gondii causes serious public health problems and is of great economic importance worldwide. Microneme proteins which are responsible for adhesion and invasion have been implicated as vaccine candidates. In this study, we constructed a DNA vaccine expressing microneme protein 6 (MIC6) of T. gondii, and evaluated the immune response it induced in Kunming mice. The gene sequence encoding MIC6 was inserted into the eukaryotic expression vector pVAXI. We immunized Kunming mice intramuscularly. After immunization, we evaluated the immune response using lymphoproliferative assay, cytokine and antibody measurements, and the survival times of mice challenged lethally. The results showed that the group immunized with pVAX-MIC6 developed a high level of specific antibody responses against T. gondii lysate antigen (TLA), a strong lymphoproliferative response, and significant levels of IFN-gamma, IL-2, IL-4 and IL-10 production, compared with the other groups immunized with empty plasmid or phosphate-buffered saline, respectively. These results demonstrate that pVAX-MIC6 induces significant humoral and cellular Th1 immune responses. After lethal challenge, the mice immunized with the pVAX-MIC6 showed an increased survival time (13.3+/-1.2 days) compared with control mice died within 7 days of challenge. Our data demonstrate, for the first time, that MIC6 triggered a strong humoral and cellular response against T. gondii, and that the antigen is a potential vaccine candidate against toxoplasmosis, worth further development.

A novel method was developed to analyze lotus rhizome polyphenolic catechin using high-performance liquid chromatography (HPLC). The retain time of catechin was 14.72 min under the optimized condition. Mass spectrometry was further employed to qualify and quantify the purity of the catechin peak. Good linearity (R=0.9997) was obtained within the range of 50-1,000 ng. The coefficient of variance was determined as 5.2%, with a recovery rate of 97%. The detection and quantification limitations of catechin were 23 ng and 50 ng, respectively. The catechin level was 0.0025% in the lotus rhizome, and 0.011% in the knot of the lotus rhizome (Nelumbo nucifera cv. 'damao jie'). The optimized conditions of HPLC for catechin detection in the lotus rhizome matrix were as follows: the SuperlcosIL™ LC-18 analytical column (150 mm×4.6 mm, 5 µm), methanol-water-acetic acid (10:90:1, volume ratio) as the mobile phase, an UV detector at 280 nm, a flow rate of 0.8 ml/min, column temperature at 30°C, and an injection volume of 10 µl.

Objective: To establish an intervention model of school health promotion, and apply it in developing "schistosomiasis-free schools"., Methods: At the pilot stage, all students of Henghu primary school and Banshan primary school in Xinjian County of Jiangxi Province were selected as experiment group and control group, respectively. A baseline survey covered knowledge and attitude on schistosomiasis control, water contact behaviors and Schistosoma japonicum infection rate. Two health promotion intervention models, i.e. "information communication + training of protection skill + reward & punishment" (model A, 1993-1999) and "information communication + behavior participation + encouragement" (model B, 2000-2007), were implemented in Henghu school. The effect of two models was compared by infection rate. At the application stage, all students of 8 schools in Xinjian County, Nanchang County, and Jinxian County were chosen for evaluation of the effectiveness of Model B with same methods and index., Results: Before intervention there was no significant statistical difference on the passed rate of anti-schistosomiasis knowledge, correct rate of anti-schistosomiasis attitude, frequency of infested water exposure and the infection rate between Henghu and Banshan schools (P > 0.05). In Henghu school, the intervention showed significant effect on the scores of knowledge and attitude after one year (P < 0.01), raised from 9.0% and 55.1% before intervention to 94.4% and 98.9% after intervention, respectively. The frequency of infested water exposure and the infection rate significantly decreased from 14.6% and 13.5% before intervention to 1.9% and 2.3%, respectively (P < 0.01). In 2-7 years after intervention, there were only one or two schistosomiasis cases each year. At the application stage, no schistosomiasis cases were found among Model B target population in two successive years after intervention., Conclusion: The practice of Model B can be extended to other schools in endemic area to develop "schistosomiasis-free schools".

The compression of 200GHz DWDM channelized optically mode-locking WRC-FPLD fiber ring pulse of at 10 GHz is performed for high-capacity TDM application. To prevent temporal and spectral cross-talk, the duty-cycle of the DWDM channelized WRC-FPLD FL pulse needs to be shortened without broadening its linewidth. With dual-cavity configuration induced DWDM channelization, a shortest single-channel WRC-FPLD FL pulsewidth of 19 ps is generated, which can be linearly compensated to 10 ps and fifth-order soliton compressed to 1.4 ps. Under a maximum pulsewidth compression ratio up to 14 and a +/-100 m tolerance on compressing fiber length, the single-channel pulsewidth remains <2 ps (duty-cycle <2%) with spectral linewidth only broadening from 0.29 nm to 0.8 nm. In comparison, a typical SOAFL without intra-cavity TBF in fiber ring broadens its spectral linewidth from 2.4 to 3.8 nm after compressing its mode-locked pulsewidth from 21 to 2.1 ps. The duty-cycle of the DWDM channelized WRC-FPLD FL pulsed carrier is approaching 1% to satisfy at least 256 optical TDM channels.

Specification of retinal rod photoreceptors is determined by several different transcription factors that activate expression of rod-specific genes and repress expression of cone photoreceptor-specific genes. The mechanism by which this dual regulation occurs is unclear. We have found that Pias3, a transcriptional coregulator and E3 SUMO ligase that is selectively expressed in developing photoreceptors, promotes the differentiation of rod photoreceptors while preventing rods from adopting cone photoreceptor-like characteristics. Pias3 binds the photoreceptor-specific transcription factors Crx and Nr2e3 and is specifically targeted to the promoters of photoreceptor-specific genes. Pias3 SUMOylates Nr2e3, converting it into a potent repressor of cone-specific gene expression. Rod- and cone-specific promoters are bound by hyperSUMOylated proteins in rod photoreceptors, and blocking SUMOylation in photoreceptors results in cells with morphological and molecular features of cones and an absence of rod-specific markers. Our data thus identify Pias3-mediated SUMOylation of photoreceptor-specific transcription factors as a key mechanism of rod specification.

Background: FIZ1 (Flt-3 Interacting Zinc-finger) is a broadly expressed protein of unknown function. We reported previously that in the mammalian retina, FIZ1 interacts with NRL (Neural-Retina Leucine-zipper), an essential transcriptional activator of rod photoreceptor-specific genes. The concentration of FIZ1 in the retina increases during photoreceptor terminal maturation, when two key transcription factors NRL and CRX (Cone-Rod Homeobox) become detectable on the promoters of photoreceptor-specific genes (i.e. Rhodopsin, Pde6b). To determine if FIZ1 is involved in regulating CRX-mediated transcriptional activation, we examined FIZ1 subcellular location in mouse neural retina, its ability to interact with CRX, and its association with CRX/NRL target genes., Results: FIZ1 is present in the nucleus of adult photoreceptors as well as other retinal neurons as shown by transmission electron microscopy with nano-gold labeling. FIZ1 and CRX were co-precipitated from retinal nuclear extracts with antibodies to either protein. Chromatin immunoprecipitation (ChIP) assays revealed that FIZ1 is part of the protein complex on several rod and cone gene promoters, within photoreceptor cells of the mouse retina. FIZ1 complexes with CRX or NRL on known NRL- and CRX-responsive elements, as shown by electrophoretic mobility shift assays with FIZ1 antibody. FIZ1 can directly bind to CRX, as demonstrated using yeast two-hybrid and GST pull-down assays. Co-transfection assays demonstrated that FIZ1 increases CRX-mediated activation of Opsin test promoters. Quantitative ChIP analysis revealed an increased association of FIZ1 with the Rhodopsin promoter in adult (P-25) neural retina versus immature (P-3) neural retina. The quantity of transcriptionally active RNA Polymerase-II within the Rhodopsin gene (Rho) was significantly increased in the adult neural retina, compared to the immature retina., Conclusion: FIZ1 directly interacts with CRX to enhance CRX's transactivation activity for target genes. Developmentally, in neural retina tissue, the increased association of FIZ1 with CRX target genes corresponds to an increased association of transcriptionally active Pol-II within the Rho gene. Together with previous findings, our results suggest that FIZ1 may act as a transcriptional co-regulator of photoreceptor-specific genes, recruited by at least two photoreceptor-specific transcription factors, CRX and NRL. Further studies are underway to elucidate the exact role of FIZ1 in photoreceptor gene expression, development and maintenance.

A novel optical TDM pulsed carrier with tunable mode spacing matching the ITU-T defined DWDM channels is demonstrated, which is generated from an optically injection-mode-locked weak-resonant-cavity Fabry-Perot laser diode (FPLD) with 10%-end-facet reflectivity. The FPLD exhibits relatively weak cavity modes and a gain spectral linewidth covering >33.5 nm. The least common multiple of the mode spacing determined by both the weak-resonant-cavity FPLD and the fiber-ring cavity can be tunable by adjusting length of the fiber ring cavity or the FPLD temperature to approach the desired 200GHz DWDM channel spacing of 1.6 nm. At a specific fiber-ring cavity length, such a least-common- multiple selection rule results in 12 lasing modes between 1532 and 1545 nm naturally and a mode-locking pulsewidth of 19 ps broadened by group velocity dispersion among different modes. With an additional intracavity bandpass filter, the operating wavelength can further extend from 1520 to 1553.5 nm. After channel filtering, each selected longitudinal mode gives rise to a shortened pulsewidth of 12 ps due to the reduced group velocity dispersion. By linear dispersion compensating with a 55-m long dispersion compensation fiber (DCF), the pulsewidth can be further compressed to 8 ps with its corresponding peak-to-peak chirp reducing from 9.7 to 4.3 GHz.

Since energy spectrum of X-ray is polychromatic source in X-ray industrial computerized tomography, the variation of attenuation coefficient with energy leads to the lower energy of X-ray radiation being absorbed preferentially when X-ray is transmitting the materials. And the higher the energy of X-ray, the lower the attenuation coefficient of X-ray. With the increase in the X-ray transmission thickness, it becomes easier for the X-ray to transmit the matter. Thus, the phenomenon of energy spectrum hardening of X-ray takes place, resulting from the interaction between X-ray and the materials. This results in false images in the reconstruction of X-ray industrial computerized tomography. Therefore, hardening correction of energy spectrum of X-ray has to be done. In the present paper, not only is the hardening phenomenon of X-ray transmitting the materials analyzed, but also the relation between the X-ray beam sum and the transmission thickness of X-ray is discussed. And according to the Beer law and the characteristics of interaction when X-ray is transmitting material, and by getting the data of X-ray beam sum, the relation equation is fitted between the X-ray beam sum and X-ray transmission thickness. Then, the relation and the method of equivalence are carried out for X-ray beam sum being corrected. Finally, the equivalent and monochromatic attenuation coefficient fitted value for X-ray transmitting the material is reasoned out. The attenuation coefficient fitted value is used for product back-projection image reconstruction in X-ray industrial computerized tomography. Thus, the effect caused by X-ray beam hardening is wiped off effectively in X-ray industrial computerized tomography.

Rod and cone photoreceptors in the mammalian retina are special types of neurons that are responsible for phototransduction, the first step of vision. Development and maintenance of photoreceptors require precisely regulated gene expression. This regulation is mediated by a network of photoreceptor transcription factors centered on Crx, an Otx-like homeodomain transcription factor. The cell type (subtype) specificity of this network is governed by factors that are preferentially expressed by rods or cones or both, including the rod-determining factors neural retina leucine zipper protein (Nrl) and the orphan nuclear receptor Nr2e3; and cone-determining factors, mostly nuclear receptor family members. The best-documented of these include thyroid hormone receptor beta2 (Tr beta2), retinoid related orphan receptor Ror beta, and retinoid X receptor Rxr gamma. The appropriate function of this network also depends on general transcription factors and cofactors that are ubiquitously expressed, such as the Sp zinc finger transcription factors and STAGA co-activator complexes. These cell type-specific and general transcription regulators form complex interactomes; mutations that interfere with any of the interactions can cause photoreceptor development defects or degeneration. In this manuscript, we review recent progress on the roles of various photoreceptor transcription factors and interactions in photoreceptor subtype development. We also provide evidence of auto-, para-, and feedback regulation among these factors at the transcriptional level. These protein-protein and protein-promoter interactions provide precision and specificity in controlling photoreceptor subtype-specific gene expression, development, and survival. Understanding these interactions may provide insights to more effective therapeutic interventions for photoreceptor diseases.

The homeodomain transcription factor Crx is required for expression of many photoreceptor genes in the mammalian retina. The mechanism by which Crx activates transcription remains to be determined. Using protein-protein interaction assays, Crx was found to interact with three co-activator proteins (complexes): STAGA, Cbp and p300, all of which possess histone acetyl-transferase (HAT) activity. To determine the role of Crx-HAT interactions in target gene chromatin modification and transcriptional activation, quantitative RT-PCR and chromatin immunoprecipitation were performed on Crx target genes, rod and cone opsins, in developing mouse retina. Although cone opsins are transcribed earlier than rhodopsin during development, the transcription of each gene is preceded by the same sequence of events in their promoter and enhancer regions: (i) binding of Crx, followed by (ii) binding of HATs, (iii) the acetylation of histone H3, then (iv) binding of other photoreceptor transcription factors (Nrl and Nr2e3) and RNA polymerase II. In Crx knockout mice (Crx(-/-)), the association of HATs and AcH3 with target promoter/enhancer regions was significantly decreased, which correlates with aberrant opsin transcription and photoreceptor dysfunction in these mice. Similar changes to the opsin chromatin were seen in Y79 retinoblastoma cells, where opsin genes are barely transcribed. These defects in Y79 cells can be reversed by expressing a recombinant Crx or applying histone deacetylase inhibitors. Altogether, these results suggest that one mechanism for Crx-mediated transcriptional activation is to recruit HATs to photoreceptor gene chromatin for histone acetylation, thereby inducing and maintaining appropriate chromatin configurations for transcription.

In X-ray TICT, when X-ray is transmitted in the materal, the phenomenon of energy spectrum hardening takes place, resulting in artifacts. Thus, hardening correction has to be done. In the present paper, the phenomenon of X-ray beam hardening resulting in analyized, and the relation between the X-ray beam sum and the transmission thickness in testing composites workpiece is discussed. According to the Beer law and the characteristics of the interaction between X-ray and the material, and getting the data of X-ray beam sum, the relation equation between the beam sum and transmission thickness is simulated firstly, and testing composites workpiece. Then, the relation and the method of equivalence are carried out between the equivalent transmission thickness and the transmission thickness for X-ray beam sum being corrected for monochromatic ray beam. Finally, the attenuation coefficient beam hardening simulated value for X-ray equivalent monochromatic is reasoned out in testing composites workpiece. Then, the attenuation coefficient simulated value that has been corrected is used for product back-projection reconstruction. Thus, the effect caused by X-ray beam hardening is wipped off effectively in testing composites workpiece.

In the case of a polychromatic source in X-ray TICT, the variation of attenuation coefficient with energy leads to low energy radiation being absorbed preferentially. In other words, the higher the energy, the lower the attenuation coefficient. With the transmission thickness augmenting, it is easier for X-ray to transmit the matter. The phenomenon is energy spectrum hardening. Thus, hardening correction has to be done. In the present paper, not only is energy spectrum hardening analyzed by theory and the relation stated between attenuation coefficient and transmission thickness in testing composites workpiece, but also the precise accurate theory model for hardening correction of energy spectrum and theory method are reasoned out in testing composites workpiece, which results from Beer's law and the characteristics of X-ray interaction with composites. Then, the attenuation coefficient that has been corrected is used for product back-projection reconstruction. Thus, the effect caused by X-ray beam hardening is wipped out effectively in testing composites workpiece.

In the case of a polychromatic source in X-ray ICT, the variation of attenuation coefficient with energy leads to low energy radiation being absorbed preferentially. In other words, the higher the energy, the more lower the attenuation coefficient. With the transmission thickness augmenting, it is easier for X-ray to transmit the matter. The phenomenon is energy spectrum hardening. Thus, hardening correction has to be done. In the present paper, not only energy spectrum hardening is analyzed by experiment and theory and the relation is stated between attenuation coefficient and transmission thickness, but also the new theory method and the precise accurate theory model for hardening correction of energy spectrum are proposed.

The transcription factors, Otx2, Crx, Nrl, and Nr2e3, expressed by retinal photoreceptor cells are essential for photoreceptor gene expression, development, and maintenance. Malfunction of any of these factors due to genetic mutations causes photoreceptor disease. Protein-protein interaction studies suggest that these factors may form a regulatory network centered on Crx. To understand how these factors regulate photoreceptor gene transcription in vivo, we have employed chromatin immunoprecipitation (ChIP) assays to assess the ability of these proteins to bind to regulatory sequences of photoreceptor genes in the retina of wild-type and mutant mice with photoreceptor degeneration. This paper summarizes the advantages and limitations of ChIP, using examples from our studies to demonstrate how this technique has contributed to our understanding of the regulation of photoreceptor gene expression. We report that Crx, Otx2, Nrl, and Nr2e3 co-occupy the promoter/enhancer, but not the region 3' of selected Crx target genes, in a retina-specific fashion. We identified Crx-dependent (Nr2e3) and Crx-independent (Otx2 and Nrl) target binding using Crx knockout mice (Crx-/-), suggesting that individual factors may use distinct mechanism(s) for binding and regulating target genes. Consistent with ChIP results, we also found that Otx2, a close family member of Crx, can activate the promoter of rod and cone genes in HEK293 cells, implicating Otx2 in regulating photoreceptor gene expression. These findings provide important information for understanding how photoreceptor transcription factors regulate photoreceptor gene expression and the mechanisms by which mutations in these factors cause transcriptional dysregulation and photoreceptor degeneration.

Objective: To investigate the prevalence, the main manifestations and related factors of sexual dysfunction in female patients with chronic renal insufficiency (CRI)., Methods: A multi-factor cooperation cross-section study was conducted. The prevalence and severity of sexual dysfunction were assessed using SCASF Microsoft., Results: The prevalence of sexual dysfunction in patients with CRI was higher than that in those without renal insufficiency (P<0.05). The main manifestations in female patients were "decreased libido, lack of orgasm and no feeling of sex pleasure". Stratified analysis on uremia showed that the prevalence and severity of sexual dysfunction of the patients on hemodialysis were similar to those on peritoneum dialysis. The women with kidney allografts suffered less "decreased-libido, lack of orgasm and no feeling of sex pleasure". Multivariate analyses demonstrated that anemia, depression, and the use of beta-blocker were risk factors for decreased libido. Ageing was a risk factor for "lack of orgasm". The use of r-HuEpo was inversely associated with "lack of orgasm"., Conclusion: Sexual dysfunctions are common in female patients with CRI. The main manifestations are decreased libido, lack of orgasm and no feeling of sex pleasure. The replacement therapy, especially kidney transplantation, could decrease the prevalence or severity of sexual dysfunction. The genesis of sexual dysfunction is multifactorial, including age, physiological factors, psychological factors and medical conditions.

Spinocerebellar ataxia type 7 (SCA7) is characterized by cone-rod dystrophy retinal degeneration and is caused by a polyglutamine [poly(Q)] expansion within ataxin-7, a protein of previously unknown function. Here, we report that ataxin-7 is an integral component of the mammalian STAGA (SPT3-TAF9-ADA-GCN5 acetyltransferase) transcription coactivator complex, interacts directly with the GCN5 histone acetyltransferase component of STAGA, and mediates a direct interaction of STAGA with the CRX (cone-rod homeobox) transactivator of photoreceptor genes. Consistent with these results, chromatin immunoprecipitation assays document retinal-specific association of CRX, GCN5, and acetylated histone H3 with CRX target genes. RNA interference studies also implicate ataxin-7 and GCN5 in CRX-dependent gene activation, and histone deacetylase inhibitors restore the compromised expression of a CRX target gene in an ataxin-7-deficient background. Significantly, in relation to SCA7, poly(Q)-expanded ataxin-7 gets incorporated into STAGA and, in a dominant-negative manner, inhibits the nucleosomal histone acetylation function of STAGA GCN5 both in vitro and, based on chromatin immunoprecipitation assays, in SCA7 transgenic mice. These results suggest that the normal function of a poly(Q) disease protein may intersect with its pathogenic mechanism, an observation with significant implications for the molecular basis of all poly(Q) disorders and ultimately for their treatment.

To investigate the molecular mechanisms of photoreceptor-specific gene transcription, we examined the role of the neuronal-enriched Sp4 nuclear protein in transcription from the rod-specific beta-PDE and rod opsin gene promoters and compared it to the ubiquitous members of the Sp family, Sp1 and Sp3. Sp4 activates both the rod opsin and beta-PDE promoters, whereas Sp1 activates only the rod opsin promoter and Sp3 activates neither promoter. Interestingly, Sp1 and Sp3 competitively repress Sp4-mediated activation of the beta-PDE promoter. In addition, Sp4, Sp1, and Sp3 each show functional synergy with the photoreceptor-enriched Crx transcriptional regulator on the rod opsin promoter but not the beta-PDE promoter, although Sp4-mediated activation was the most significant. Sp4, Sp1, and Sp3 bind Crx in co-immunoprecipitation experiments, and their zinc finger domains as well as the Crx homedomain are necessary and sufficient for these interactions. Chromatin immunoprecipitation showed that the rod opsin and beta-PDE promoters are targets of both Sp4 and Crx, which further supports Sp4-Crx interactions in vivo in the context of retinal chromatin environment. In situ hybridization and immunohistochemistry demonstrated that Sp4 is abundantly expressed in various neurons of all retinal layers, and thus co-localizes or overlaps with multiple retina-restricted and -enriched genes, its putative targets. Our results indicate that photoreceptor-specific gene transcription is controlled by the combinatorial action of Sp4 and Crx. The other Sp family members may be involved in photoreceptor-specific transcription directly or through their competition with Sp4. These data suggest the potential importance of Sp4 in retinal neurobiology and pathology.

Nr2e3 is an orphan nuclear receptor expressed specifically by retinal photoreceptor cells. Mutations in Nr2e3 result in syndromes characterized by excess blue cones and loss of rods: enhanced S-cone syndrome (ESCS) in humans and rd7 in mice. Using yeast two-hybrid screens with Nr2e3 as bait, the cone-rod homeobox protein Crx was identified as an interacting partner of Nr2e3. Immunoprecipitation assays confirmed this Nr2e3-Crx interaction and identified the DNA-binding domain of each protein as the interaction motif. Immunohistochemistry demonstrated that Crx and Nr2e3 are co-expressed by rod photoreceptors and their precursors. Chromatin immunoprecipitation assays on mouse retina demonstrated that Nr2e3 and Crx co-occupy the promoter/enhancer region of several rod and cone genes in the rod photoreceptor cells. The promoter/enhancer occupancy of Nr2e3 is Crx-dependent, suggesting that Nr2e3 is associated with photoreceptor gene targets by interacting with Crx. Transient transfection assays in HEK293 cells demonstrated that Nr2e3 enhances rhodopsin, but represses S- or M-cone opsin transcription when interacting with Crx. Quantitative real-time RT-PCR analysis on postnatal day 28 (P28) retina of the rd7 mouse, which lacks Nr2e3 protein, revealed an up-regulation of cone genes, but down-regulation of rod genes. Several mutant forms of human Nr2e3 identified from ESCS patients showed defects in interacting with Crx and/or in transcriptional regulatory function. Altogether, our findings suggest that Nr2e3 is a dual-function transcriptional regulator that acts in concert with Crx to promote and maintain the function of rod photoreceptors.

Objective: To induce the apoptosis of human alveolar epithelial cells (A549) by the extraction of the second stage larvae of Ascaris lumbricoides and investigate the extraction concentration and inducing time related to the apoptosis., Methods: Following to the results of Microculture Tetrazolium Test (MTT), five concentrations of the extraction of the second stage larvae were chosen to induce the apoptosis of A549 cells. Meanwhile, control groups without the inducement were set up. For each group, observation was made at five time points since the start of inducement, to assess the existence of apoptosis and percentage of cells showing characteristics of apoptosis. HE stain and diphenylamine reaction methods were used to assess the cell apoptosis. Agarose gel electrophoresis of DNA and flow cytometry were also employed to confirm the apoptosis for some groups., Results: Observations indicated that the apoptosis ratio of A549 cells induced by the extraction at different concentrations were significantly higher than that of the control cells (P < 0.05). At most time points of observation, the apoptosis ratio increased with the increase of concentration, indicating a positive correlation between them. For each concentration group, the apoptosis ratio increased as the inducing time prolonged until a peak appeared at 5 h of the inducement., Conclusion: The extraction of the second stage larvae of Ascaris lumbricoides can induce apoptosis of human alveolar epithelial cells in vitro with a concentration-dependent pattern. With regard to the relationship of apoptosis to the time of inducement, two trends were revealed and the relationship also influenced by the concentration of the larvae extraction.

Spinocerebellar ataxia type 7 (SCA7) is an inherited neurodegenerative disorder caused by expansion of a polyglutamine tract in the ataxin-7 protein. A unique feature of SCA7 is degeneration of photoreceptor cells in the retina, resulting in cone-rod dystrophy. In an SCA7 transgenic mouse model that we developed, it was found that the cone-rod dystrophy involves altered photoreceptor gene expression due to interference with Crx, a homeodomain transcription factor containing a glutamine-rich region. To determine the basis of the Crx-ataxin-7 interaction, Crx and ataxin-7 truncation and point mutants were generated, and the ability of mutant versions of either protein to co-immunoprecipitate the normal version of the other protein was tested. Thus Crx's ataxin-7 interaction domain was localized to its glutamine-rich region and ataxin-7's Crx binding domain was mapped to its glutamine tract. The importance of each protein's respective glutamine region for a productive interaction was confirmed by performing Crx transactivation assays in HEK293 cells and correlating the extent of Crx transcription interference with the intactness of each protein's glutamine region. It was also established that ataxin-7 must localize to the nucleus to repress Crx transactivation, and the likely nuclear localization signals were mapped to ataxin-7's carboxy-terminal region. Finally, using chromatin immunoprecipitation, it was demonstrated that Crx and ataxin-7 engage in a functionally significant interaction by co-occupying the promoter and enhancer regions of Crx-regulated retinal genes in vivo. The results suggest that one mechanism of SCA7 disease pathogenesis is transcription dysregulation, and that Crx transcription interference is a predominant factor in SCA7 cone-rod dystrophy retinal degeneration.

Objectives: To investigate the prevalence, main manifestation and related factors of sexual dysfunction in male patients with chronic renal insufficiency (CRI)., Methods: A cross-section study was conducted by six hospitals in Sichuan Province. The prevalence and severity of sexual dysfunction were assessed by SCASF microsoft among patients with chronic renal disease. Logistic regression was used to examine and test the association between sexual dysfunction and other medical conditions., Results: The prevalence of sexual dysfunction was wider in patients with CRI than in those without. The main manifestations in male patients were decreased libido, erectile dysfunction and premature ejaculation. Stratified analysis in uremia showed that the prevalence and severity of sexual dysfunction were similar between patients on haemodialysis(HD) and those on peritoneal dialysis(PD). The patients receiving no replacement treatment suffered more decreased libido and performance anxiety than dialyzed patients (HD and PD) and transplantation patients(Tx). The patients receiving no replacement treatment and dialysis suffered more erectile dysfunction than Tx men. A multivariable analysis demonstrated that the duration, creatinine clearance(Ccr), parathyroid hormone (PTH), albumin(Alb) were not associated with sexual dysfunction. The use of beta-blocker, anemia and depression were risky factors for decreased libido, and increasing age was a risky factor for erectile dysfunction. The use of angiotensin-converting-enzyme inhibitor(ACEI)/angiotention receptor antagonist (ARB) and recombinant human erythropoietin(r-HuEpo) were protective factors for erectile dysfunction., Conclusions: The main manifestations of sexual dysfunction in male patients with CRI are decreased libido, erectile dysfunction and premature ejaculation. The replacement therapy, especially transplantation, can decrease the prevalence or severity of sexual dysfunction. The genesis of sexual dysfunction is multifactorial, including age, physiological factors, psychological factors and medical conditions.

Sexual dysfunction is a highly prevalent problem among patients with chronic renal failure, which affects patients in the quality of life. However, it has not received enough attention. The genesis of sexual dysfunction is multifactorial, including physiological, psychological and organic factors. This review summarized the incidence, main manifestation, evaluation, risk factors and treatments associated with sexual dysfunction in patient of the chronic renal failure.

Crx (cone-rod homeobox) is a homeodomain transcription factor implicated in regulating the expression of photoreceptor and pineal genes. To identify proteins that interact with Crx in the retina, we carried out a yeast two-hybrid screen of a retinal cDNA library. One of the identified clones encodes Baf (barrier to autointegration factor), which was previously shown to have a role in mitosis and retroviral integration. Additional biochemical assays provided supporting evidence for a Baf-Crx interaction. The Baf protein is detectable in all nuclear layers of the mouse retina, including the photoreceptors and the bipolar cells where Crx is expressed. Transient transfection assays with a rhodopsin-luciferase reporter in HEK293 cells demonstrate that overexpression of Baf represses Crx-mediated transactivation, suggesting that Baf acts as a negative regulator of Crx. Consistent with this role for Baf, an E80A mutation of CRX associated with cone-rod dystrophy has a higher than normal transactivation potency but a reduced interaction with Baf. Although our studies did not identify a causative Baf mutation in retinopathies, we suggest that Baf may contribute to the phenotype of a photoreceptor degenerative disease by modifying the activity of Crx. In view of the ubiquitous expression of Baf, we hypothesize that it may play a role in regulating tissue- or cell type-specific gene expression by interacting with homeodomain transcription factors.

Objective: To use a high performance liquid chromatography with electrochemical detection to simultaneously determine catecholamine(CA) levels in plasma and to diagnose chromaffin cell tumors and neuroblastoma., Methods: The plasma samples after flowing extraction by ion-moderated partition were determined with electrochemical method to detect CA levels in plasma; the lowest detective limit, the precision, recovery, sensitivity of CA levels were tested and a reference range was established based on the respective data of 18 healthy persons., Results: The recovery rates of epinephrine and norepinephrine were 86.2% and 90.5%. The method of testing epinephrine was linear at the range of 0.2 to 10.6 nmol.L-1 with 0.05 nmol.L-1 of the lowest detective limit. The intra- and inter-assay coefficients of variation were lower than 10.7% and 11.1%, respectively., Conclusion: The method is simple, accurate, sensible in the clinical diagnosis of CA levels.

To determine the mechanism of congenital nystagmus (CN), the ultrastructure of the extraocular muscle in CN patients was examined with the transmission electron microscope. The specimen of muscle tissue was taken during surgery from horizontal recti in the slow and quick phase sides separately in the jerky type, and medial and lateral recti in the pendular type. The extraocular muscle was immediately fixed in 2.5% glutaraldehyde solution. (1) In the jerky type, the myocytes in the quick phase side showed myofibrillae that were perpendicular to axes of myocytes and had the structure of sarcomeres. In the slow phase side there were perpendicular myofibrillae in the periphery of myocytes. (2) In the pendular type, there were no perpendicular myofibrillae within myocytes. The myofibrillae that were parallel to the axes of myocytes were arranged disorderly. The length of the H and I bands in different myofibrillae was not identical. These results demonstrated, for the first time, the ultrastructural changes in the extraocular muscle of CN patients, which might provide the pathological basis for this disease.

The recombinant single chain urokinase-type plasminogen activator (rscu-PA) and a mutant constructed by in vitro site-specific mutagenesis of Argl54 in rscu-PA to Glul54 (Glul54-mscu-PA) were both expressed in E. coli. The expressed products were both purified to homogeneity by in vitro denaturation and renaturation, followed by Zn(2+) selective precipitation and immuno-affinity chromatography. The plasmin sensitivity assay indicated that the activation of this single chain Glul54-mscu-PA by plasmin was essentially identical to that of rscu-PA. After activation by plasmin, the kinetic constants against synthetic substrate S2444 of the resulted two chain form of Glul54-mscu-PA (Glul54-mtcu-PA) and that of rscu-PA (rtcu-PA) were 87 &mgr;M and 80 &mgr;M, respectively, which indicated that the catalytic active site of the Glul54-mtcu-PA was not changed by the mutation. Whereas, both (125)I-fibrin plasma-clot lysis and fibrinogenolysis in plasma showed that the Glul54-mtcu-PA possessed a better affinity and selectivity for fibrin than rtcu-PA, even better than rscu-PA.

Experiments were made to ascertain the effects of covering windowpane with plastic film in Hulunbeir region on microclimate and sunshine intensity in the living room. It was found that a good regulative effect on the room microclimate resulted by covering the windowpane with plastic film in the cold region. The room temperature rose distinctly. No evident effects were found on ultra-violet radiation and illumination. But the concentration of carbon dioxide increased to some extent. Attention should be paid to ventilation of the room.