[Differences in Fungal Communities in Different Material Cellar Sediments and Their Correlation with Environmental Factors]

There are rich and diverse fungal communities in rainfall-cellar sediments. Fungi play a key role in the rainfall-cellar ecosystem as a bridge and link for material exchange between the rainfall-cellar ecosystem and the sediments. The changes in fungal community structure are usually closely related to the changes in environmental factors. The 16S rRNA gene Illumina MiSeq high-throughput sequencing technology was used to study the diversity and difference of fungal communities in the cellar sediments under two different catchment environments. The results revealed that the cellar sediments under the concrete catchment environment had higher diversity and richness of fungal communities than those under the loess land catchment environment. The dominant bacteria of the fungal communities under the two catchment environments were the same, namely Ascomycota, Basidiomycota, and Zygomycota, which constituted more than 90% of the abundance of the bacteria; however, the former had better homogeneity and stability. The indicator species based on LEfSe analysis demonstrated that Basidiobolales had the largest contribution to the diversity in the catchment environment of the loess land, and Mycosphaerella had the smallest contribution; Saccharomycetales contributed the most to the diversity in the concrete concentration environment, whereas Periconia contributed the least. The results of the co-occurrence network of the microbial community and environmental factors demonstrated that the positive relationship between fungi and environmental factors was stronger than the negative relationship. The research results have enhanced the understanding of the diversity of fungal communities in the cellar sediments and provided a reference for ensuring the drinking safety of rainwater harvesting cellar water for humans and livestock and improving the quality of cellar water.

[Natural history of colorectal cancer: a Meta-analysis on global prospective cohort studies]

Objective: To acknowledge the availability and rates of annual transition of outcomes during the progression and regression stages of colorectal cancer (CRC) and related diseases, by pooling global follow-up studies on the natural history of CRC. Methods: Till March, 2017, data was collected through systematic literature review over multiple databases, including PubMed, Embase, Cochrane and Chinese Biology Medicine (CBM) disc. Information regarding the characteristics, classification system of health states, related outcomes and incidence rates on CRC or high-risk adenoma for the surveillance cohorts of the studies, were extracted and summarized. Both Meta and sensitivity analyses were performed on those outcomes if they appeared in more than 3 studies, using the random effects model. Annual transition rate with 95%CI was used to estimate each of the outcomes, Quality of the studies was assessed, using the Newcastle-Ottawa Scale. Results: A total of 29 cohort studies were included, with the mean follow-up period as 5.7 years. All studies except one, focused on adenoma-carcinoma pathway and reported the outcome parameters of adenomas by different risk, and some reported the findings on different sizes (n=6) of adenomas. These cohorts were divided into three groups (normal status, with low-risk or high-risk adenoma) according to the status of baseline endoscopic pathologic findings. Their available outcome parameters, corresponding number of involved articles, aggregated sample size and pooled annual transition rates were presented. Six parameters were obtained in the normal cohorts, including those from normal to low-risk adenoma (16 articles, 58 235, 0.030: 0.024-0.037), to high-risk adenoma (17 articles, 62 089, 0.003: 0.002-0.004), to diminutive adenoma (<5 mm, 4 articles, 1 277, 0.021: 0.013-0.029), to small adenoma (6-9 mm, 4 articles, 1 277, 0.006: 0.001-0.010), to large adenoma (≥10 mm, 7 articles, 3 531, 0.002: 0.000-0.003) and to CRC (19 articles, 104 836, 0.000 3: 0.000 2-0.000 5). Three parameters were obtained in low-risk adenoma in cohorts with polypectomy findings, including recurrence (9 articles, 4 788, 0.109: 0.062-0.157) from low-risk adenoma after polypectomy to high-risk adenoma (10 articles, 5 736, 0.009: 0.004-0.013) and to CRC (12 articles, 11 347, 0.000 6: 0.000 4-0.000 8). Three parameters were obtained on high-risk adenoma from cohorts with polypectomy findings, including recurrence (12 articles, 7 030, 0.038: 0.028-0.048) from high-risk adenoma after polypectomy to low-risk adenoma (8 articles, 2 489, 0.133: 0.081-0.185) and CRC (14 articles, 14 899, 0.002: 0.001-0.003). Except for normal to low-risk adenomas, results from the sensitivity analysis for the other parameters showed stable. Of the included studies, two presented incidence rates of CRC in different clinical stages and the another two were focusing on the parameters related to serrated pathway. Conclusions: Globally, follow-up studies reported data on natural history of colorectal cancer is of paucity. Compared to the "adenoma-carcinoma" pathway, transition parameters of the serrated lesion pathway are more limited. This Meta-analysis provided convincing evidence for optimizing the strategies regarding follow-up program on the disease, using the baseline endoscopic findings from global CRC Screening Program. These results also offered strong data-related support for Chinese population- specific interventional model on colorectal cancer.

[Oxidative Stress Status and Its Effect on Regulation of Hepcidin in Patients with HbHCS]

OBJECTIVE

To investigate the oxidative stress status and its effects on hepcidin in patients with hemoglobin H Constant Spring disease (HbH-CS).

METHODS

A total of 35 patients were enrolled in the study, including 15 splenectomized cases and 20 non-splenectomized cases. 20 healthy volunteers were selected as controls. Serum superoxide dismutase (SOD), malondialdehyde (MDA), glutathione (GSH), oxidized glutathione (GSSG) levels, erythropoietin (EPO), serum free transferrin receptor (sFTR), growth differentiation factor 15 (GDF15) as well as the level of hepcidin were detected. Correlation analysis and multiple factor regression analysis were performed to investigate the factors affecting the iron metabolism and erythropoiesis.

RESULTS

Compared with healthy control, the SOD and GSH levels in patients with HbHCS decreased, while MDA and GSSG levels increased. The levels of SOD, MDA, GSG and GSSG were not significantly different between the patients with splenectomy and those without splenectomy. Correlation analysis showed that inpatients with HbHCS, EPO, sFTR and GDF15 correlated negatively with SOD level and positively with MDA level. EPO and sFTR levels negatively correlated with Hepcidin.

CONCLUSION

Excessive oxidative stress is present in patients with HbHCS, and hepcidin is inhibited by the upregulation of EPO and sFTR, and hence involved in iron overload in patients.

[An investigation of mental health in migrant workers in an enterprise]

Objective: To investigate the mental health status in migrant workers in a labor-intensive enterprise and related influencing factors. Methods: Typical sampling was used to perform an investigation in 910 migrant workers in a large foreign-funded labor-intensive enterprise in Shenzhen, China. All the respondents gave informed consent and completed the questionnaire independently and anonymously. The self-reported mental health status was evaluated using the Beck Anxiety Inventory, Beck Depression Inventory, and General Health Questionnaire. Results: Of all the migrant workers in this enterprise, 7.2% had a positive self-reported anxiety symptom, 25.4% had a moderate or severe self-reported depression symptom, and 76.4% had a poor self-reported general health status. Age had significant influence on the self-reported depression symptom (χ²=21.968, P<0.05) ; age did not have significant influence on the self-reported anxiety and general health status (χ²=6.616、12.498, both P>0.05) . The knowledge of occupational hazards had significant influence on mental health status (χ²_Depression=47.289, χ²_{General health}=21.087, both P<0.05) . The feeling of work had significant influence on self-reported depression and general health status (χ²_Depression=52.406, χ²_{General health}=17.327, both P<0.05) . Attention to self mental health had significant influence on self-reported depression (χ²=17.714, P<0.05) , and whether the person wanted to learn the knowledge of mental health had significant influence on self-reported anxiety (χ²= 6.145, P<0.05) . Conclusion: The self-reported mental health status in migrant workers is poor and is associated with age, worry about exposure to occupational hazard factors, emphasis on mental health knowledge, and a focus on personal mental health. Therefore, targeted occupational health education and occupational mental health education should be strengthened.

Human cytomegalovirus UL49 encodes an early, virion-associated protein essential for virus growth in human foreskin fibroblasts

Despite recent results of deletion experiments showing that open reading frame (ORF) UL49 of human cytomegalovirus (HCMV) is essential, the expression, function and functional location of its encoded protein remain unknown. We generated an antibody specific for pUL49 to investigate the protein product encoded by the UL49 ORF and identified its function in HCMV-infected host foreskin fibroblasts. A bacterial artificial chromosome (BAC) of HCMV strain Towne (pRV-Towne) and the UL49-deleted mutant pRV-delUL49Towne were used to observe virus growth by plaque assay. Using a UL49-protein-binding antibody, we located pUL49 in the fibroblast cytoplasm. pUL49 exhibited expression kinetics resembling those of the class β-2 proteins and was detected in the virion tegument. Following deletion of UL49 ORF, the virus failed to replicate, but it could be recovered by addition of pUL49 from pCDNA3.1 (+)-UL49. Our findings indicate that UL49 ORF is essential for HCMV replication in host foreskin fibroblasts.

[Comparisons of risk factors for low birth weight between Han and Uygur full-term infants]

OBJECTRIVE

To compare the differences in risk factors for low birth weight (LBW) between Han and Uygur full-term infants and to provide a basis for the prevention of LBW in newborn infants.

METHODS

Eighty-seven full-term LBW infants (38 Hans and 49 Uygurs) between March 2013 and June 2014 were selected as the case group, and 186 full-term normal birth weight infants (92 Hans and 94 Uygurs) were selected as the control group. A questionnaire survey was performed to investigate the related factors for LBW. Multivariate logistic regression analysis was carried out to determine the risk factors for LBW.

RESULTS

The birth weights in Uyghur LBW infants were lower than in Han ones (P<0.05). Multivariate logistic regression analysis showed that drinking (OR=2.472, P=0.015) and smoking (OR=2.323, P=0.007) by the father, pregnancy complications (OR=14.377, P<0.001), and times of pregnancy (OR=2.995, P=0.001) were the risk factors for LBW in Han infants, while drinking by the father (OR=1.968, P=0.007), times of pregnancy (OR=1.953, P=0.005), pregnancy complications (OR=10.283, P=0.002), and poor indoor environment (OR=1.367, P=0.027) were the risk factors for LBW in Uyghur infants.

CONCLUSIONS

There are differences in physical growth between Han and Uygur LBW infants. Han and Uygur infants share the same traditional risk factors for LBW, such as father's harmful behaviors like drinking, times of pregnancy, and pregnancy complications, however, the indoor environment also plays a role in the occurrence of LBW in Uygur infants.

Pulmonary hypertension risk in patients with hemoglobin h disease: low incidence and absence of correlation with splenectomy

Pulmonary hypertension (PHT) is a common complication for patients with β thalassemia intermediate (TI), especially splenectomized patients. However, the frequency and risk factors of PHT in patients with hemoglobin H (HbH) disease is unknown. The purpose of this study was to identify the prevalence of PHT risk manifested as tricuspid regurgitant jet velocity (TRV) ≥2.5 m/s in patients with HbH disease and its correlation with splenectomy. One hundred and ninety-eight patients with HbH disease who visited the 303rd Hospital of the People's Liberation Army (Nanning, China) were investigated. Thirteen subjects (6.5%) were diagnosed as having a risk of PHT. Regression analyses showed that the prevalence of PHT risk was correlated only with age (r = 0.195, p = 0.006) and not with splenectomy. The risk of PHT in patients older than 35 years was 5.7 times (range 1.8-18.6) greater than that for patients younger than 35 years. For splenectomized patients compared to those with HbH disease, patients with TI had a higher frequency of PHT risk, higher nucleated red blood cell counts (46.03 ± 41.11 × 10(9)/l vs. 0.18 ± 1.19 × 10(9)/l, p < 0.001) and a higher platelet counts (837.6 ± 178.9 × 10(9)/l vs. 506.7 ± 146.2 × 10(9)/l, p < 0.001). PHT risk is low in patients with HbH disease and does not correlate with splenectomy. Patients older than 35 years should be monitored regularly.

Construction and expression of a recombinant eukaryotic expression plasmid containing the preS1-preS2-S genes of hepatitis B virus and the granulocyte-macrophage colony stimulating factor gene: A study of its immunomodulatory effects

A total of 10-20% of the population remains unresponsive or weakly responsive to hepatitis B vaccine, which is composed of hepatitis B surface antigen HBsAg (S protein). Therefore, it is necessary to develop a hepatitis B vaccine with a better penetrating and responsive rate. In the present study, a plasmid pVAX1-L-GM was constructed and its immunomodulatory effect of as hepatitis B virus (HBV) DNA vaccine was analyzed through the immunization of BALB/c mice. Immune responses were measured after immunization by anti-HBsAg, proliferation of splenocytes, the number of CD4⁺ and CD8⁺ molecules, CTL cytotoxicity, cytokines of IFN-γ and IL-2 secretion assays. Following the immunization, mice in the pVAX1-L-GM group produced antibody 2 weeks earlier compared to the control plasmid pVAX1 and pVAX1HBsAg groups and antibody levels showed significant differences. Enhanced HBsAg-specific splenocyte proliferation as well as specific cytotoxic activities of splenic CTLs were also detected. Furthermore, pVAX1-L-GM plasmid increased the number of CD4⁺ and CD8⁺ molecules on the surface of the spleen T cell and the level of IFN-γ, IL-2 secretion. pVAX1-L-GM induced a specific immune response in mice and enhanced the immune effect. Thus, a foundation was laid for developing immunogenicity of a better prevention and treatment of HBV via a hepatitis B vaccine.

Treatment and complications of thalassemia major in Guangxi, Southern China

BACKGROUND

β-Thalassemia is extremely prevalent in Guangxi province, Southern China. However, little is known about the treatment and complications of patients with thalassemia major (TM) in Guangxi. The first thalassemia center in China was opened in Guangxi in 2003. Since that time, more than 400 patients have been enrolled.

PROCEDURE

From December 2009 to February 2010, data was collected from TM patients visiting the thalassemia center including the circumstances of diagnosis, biological and clinical data, markers of iron overload and treatment.

RESULTS

Data on 231 patients (median age, 5 years; range, 5 months to 21 years) were recorded. Only 44.6% of patients maintained their hemoglobin levels >9.0 g/dl. In 186 patients with ferritin levels >1,000 ng/ml, an iron chelator was used regularly in 44.6%, irregularly in 26.9%, and was not used in 28.5%. The mean serum ferritin level was 3,143 ng/ml and levels increased with age. Height and weight retardation were found in 48.3% and 11.1% patients, respectively. Compared to patients treated outside of the center, patients completing treatment in the thalassemia center had a higher hemoglobin level before transfusion, higher height and weight SD score, and less splenomegaly, but a similar ratio of regular or irregular iron chelation. Six (18.2%) of 33 patients >10 years of age (14.3 ± 2.8 years; range, 11-19 years) were diagnosed as hypothyroid.

CONCLUSIONS

Although survival status of patients with TM in Guangxi has improved since the opening of the thalassemia center, TM complications remain high and with an early onset.

[Identification of ubiquitously expressed transcript as the potential interactor of hepatitis B virus polymerase]

OBJECTIVE

To investigate the function of hepatitis B virus polymerase (HBV Pol) in the viral life cycle by screening the proteins interacting with HBV polymerase.

METHODS

The HBV Pol gene was constructed into the pGBKT7 vector. GAL4 yeast two-hybrid system was used to screen the human liver cDNA library to obtain proteins which interacted with HBV Pol. GST-pull down assay was applied to confirm the protein interactions.

RESULTS

Ubiquitously expressed transcript (UXT) was selected by the yeast two-hybrid system. GST-pull down assay confirmed the in vitro interaction between HBV Pol and UXT.

CONCLUSIONS

UXT is a potential interactor of HBV Pol, and this protein interaction may provide clues of the function of HBV Pol in HBV life cycle.

A case report of concomitant paroxysmal nocturnal hemoglobinuria and heterozygous β-thalassemia

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare clonal blood disorder that presents chronic intravascular hemolysis. PNH concomitant with inherited hemolytic anemia has been rarely reported. Here, we report an interesting PNH patient who was misdiagnosed with iron deficiency anemia due to concomitant heterozygous β-thalassemia. The patient experienced dizziness, fatigue, and restricted physical activity for the previous 3 years. Thalassemia gene analysis revealed heterozygous β-thalassemia. Iron staining of the bone marrow demonstrated the absence of stainable iron and sideroblasts. The patient was diagnosed with iron deficiency anemia. Iron supplementation treatment was performed, but the anemia remained unresolved. The patient became transfusion dependent 1 year later and was admitted to our hospital in March 2010. Flow cytometry of the patient's peripheral blood demonstrated that 7.9% and 11.9% of the erythrocytes were CD59 and CD55 deficient, respectively. The patient was finally diagnosed with concomitant PNH and heterozygous β-thalassemia.

Effective inhibition of HCMV UL49 gene expression and viral replication by oligonucleotide external guide sequences and RNase P

Background

Human cytomegalovirus (HCMV) is a ubiquitous herpesvirus that typically causes asymptomatic infections in healthy individuals but may lead to serious complications in newborns and immunodeficient individuals. The emergence of drug-resistant strains of HCMV has posed a need for the development of new drugs and treatment strategies. Antisense molecules are promising gene-targeting agents for specific regulation of gene expression. External guide sequences (EGSs) are oligonucleotides that consist of a sequence complementary to a target mRNA and recruit intracellular RNase P for specific degradation of the target RNA. The UL49-deletion BAC of HCMV was significantly defective in growth in human foreskin fibroblasts. Therefore, UL49 gene may serve as a potential target for novel drug development to combat HCMV infection. In this study, DNA-based EGS molecules were synthesized to target the UL49 mRNA of human cytomegalovirus (HCMV).

Results

By cleavage activity assessing in vitro, the EGS aimed to the cleavage site 324 nt downstream from the translational initiation codon of UL49 mRNA (i.e. EGS324) was confirmed be efficient to direct human RNase P to cleave the target mRNA sequence. When EGS324 was exogenously administered into HCMV-infected human foreskin fibroblasts (HFFs), a significant reduction of ~76% in the mRNA and ~80% in the protein expression of UL49 gene, comparing with the cells transfected with control EGSs. Furthermore, a reduction of about 330-fold in HCMV growth were observed in HCMV-infected HFFs treated with the EGS.

Conclusions

These results indicated that UL49 gene was essential for replication of HCMV. Moreover, our study provides evidence that exogenous administration of a DNA-based EGS can be used as a potential therapeutic approach for inhibiting gene expression and replication of a human virus.

Hemoglobin H disease in Guangxi province, Southern China: clinical review of 357 patients

The clinical characteristics of 357 patients with hemoglobin H (HbH) disease from the Guangxi province of Southern China were studied. One hundred and ninety-one (53.3%) patients were diagnosed with HbH-Constant Spring, 19 were diagnosed with HbH Westmead. Ten patients were shown to have coinherited HbH-Constant Spring/QS with a β-thalassemia mutation. Coinheritance of the β-thalassemia gene does not alleviate anemia (8.2 ± 2.3 vs. 7.6 ± 1.7 g/dl, p = 0.276), or influence age at diagnosis (20.2 ± 19.6 vs. 12.9 ± 11.0 years, p = 0.276). Ferritin levels were significantly higher in the group of patients with the nondeletional form of the disease (475 ± 719 vs. 249 ± 264 ng/ml, p = 0.005).

High-level expression, polyclonal antibody preparation and sub-cellular localization analysis of mouse Rhox5 protein

Mouse reproductive homeobox on the X chromosome (Rhox) is a novel homeobox gene cluster. Rhox5, also called Pem, belongs to the beta subcluster of Rhox. Codon analysis indicated that the cDNA contains 16% of codons rarely used in Escherichia coli. To achieve high-level expression of Rhox5, the coding sequence of Rhox5 was amplified and subcloned into the prokaryotic expression vector pET22b (+) in order to produce 6His-tagged fusion protein in the modified BL21 (DE3) cells, namely Rosetta2 (DE3) cells. The 6His-tagged Rhox5 was expressed efficiently in Rosetta2 (DE3), compared with marginal expression in BL21 (DE3). The fusion protein amounted to 16% of the total bacterial proteins after induction with 0.4mM IPTG for 1.5h at 37 degrees C. After purification, Rhox5-6His was used to immunize New Zealand white rabbits following standard protocol. The homemade antiserum could detect both endogenous Rhox5 protein expressed in eukaryotic cells (Cos-7) and exogenous GFP-Rhox5 protein. Furthermore, the antiserum was used to determine the localization of Rhox5 in NIH3T3 cells using an immunofluorescence technique. The results demonstrated that Rhox5 was localized predominantly in the nucleus. Preparation of the anti-Rhox5 polyclonal antibody will facilitate further functional study of Rhox5.

[Construction of vector of multiple loci gene targeting in leghorn chicken based on BAC with Cre/lox P system]

Based on the sequence of BAC (Bacterial Artificial Chromosome) along with the Cre/lox P system, the gene-targeting vectors to multiple loci of the repetitive internal transcribed spacers between rDNA genes in Leghorn chicken were constructed. The key material of multiple loci gene targeting in vivo would be obtained. First, the plasmid of pYLSV-TDN with TK, HRDS2, and Neo genes was constructed. The TK-HRDS2-Neo DNA fragment obtained from the plasmid of pYLSV-TDN was digested by Not I/HindIII and inserted into the upstream of the lox P site of BAC plasmid for obtaining the selective vector of BAC-TDN. The expression vector of pYLVS-GID with EGFP, hIFN genes, and HRDS1 was then obtained. The plasmid of BAC-TDN-VS-GID was obtained by cotransformation of the selective vector of BAC-TDN and the expression vector of pYLVS-GID to E. coli NS3529 through the action of Cre/lox P system. The gene-targeting vector of BAC-TDN-GID to multiple loci of the ITS region in Leghorn chicken was obtained by cleaving the sequence of pYLVS with the homing endonuclease of I -Sce I and ligating with the linker of LS. The insertion and the insert direction of DNA fragments were identified by restriction digestion or PCR and sequencing in each clone. The significance of the technique ofgene-targeting vector to multiple loci are shown as follows. First, the targeting loci were increased to 100 - 300. Second, the problems of unstable expression of inserted genes were partially solved. Third, the need for safety against toxicity integration was resolved. Fourth, the forbidden zone of gene integrating on the repetitive DNA sequences was broken through.

Combination of multiple mRNA markers (PTTG1, Survivin, UbcH10 and TK1) in the diagnosis of Taiwanese patients with breast cancer by membrane array

OBJECTIVE

Early detection is a prerequisite to the effective reduction of morbidity and mortality from breast cancer. The present study intended to employ a high-throughput membrane array to detect a panel of mRNA markers expressed by circulating tumor cells (CTCs) in the peripheral blood of female patients with breast cancer.

METHODS

Peripheral blood was sampled from 92 breast cancer patients and 100 normal persons. CTCs were detected by using a membrane array technique. The markers used included the pituitary tumor transforming gene 1, survivin, UbcH10 and thymidine kinase 1.

RESULTS

The results showed that the membrane array could positively detect 5 cancer cells per 1 ml of peripheral blood in breast cancer cell dilution experiments. For the panel of 4 mRNA markers, sensitivity and specificity were elevated up to 86 and 88%, respectively. Furthermore, it was found that the patients' clinicopathological characteristics tumor size (p = 0.006), histologic grade (p = 0.012), lymph node metastasis (p = 0.001) and TNM stage (p = 0.006) significantly correlated with the positive detection rate of the multimarker panel.

CONCLUSIONS

These findings demonstrated that our multimarker membrane array method could detect CTCs in the circulation of breast cancer patients with considerably high sensitivity and specificity.

Genomics innovative teaching pattern based upon amalgamation between modern educational technology and constructivism studying theory

In order to overcome various malpractices in the traditional teaching methods, and also as part of the Guangdong province molecular biology perfect course project, some reforms were carried out to the teaching pattern of genomics. The reforms include using the foreign original teaching materials, bilingual teaching, as well as taking the constructivism-directed discussion teaching method and the multimedia computer-assisted instruction. To improve the scoring way and the laboratory course of the subject, we carried on a multiplex inspection systems and a self-designing experiments. Through the teaching reform on Genomics, we have gradually consummated the construction of molecular biology curriculum system.

[Expression and characterization of VPAC2 in CHO cells]

VPAC2 is a co-receptor of pituitary adenylate cyclase activating polypeptide (PACAP) and vasoactive intestinal peptide (VIP) and mediates multiple bio-functions. In order to construct the CHO line expressing VPAC2 stably, pcDNA-VPAC2 was used to transfect CHO cells. The positive clones were selected by G418 and the clone VPAC2-CHO with high sensitivity to PACAP38 was picked out by its ability to promoting the concentration of cAMP. RT-PCR, Western blot and Immunofluorescenece assay were used to identify the express of VPACS. Binding competition with VPAC2 agonist and the bioactivity of mediating the ligand to promote the concentration of cAMP showed that VPAC2 was expressed effectively in VPAC2-CHO. The results of Scatchard analysis revealed that VAPC2-CHO expressed a receptor density of (1.1 +/- 0.2) pmol/mg protein, respectively, with Kd values of (0.55 +/- 0.10) nmol/L for PACAP38 used as a tracer. The construction of CHO cells expressing VPAC2 specially and functionally lays a foundation not only for the further research on the characters and functions of VPAC2 but also for the screening and characterization of novel agonists of antagonists for VPAC2.

[Research progress on cell apoptosis during embryonic development of the zebrafish (Danio rerio)]

Cells have a built-in death program through the regulation of genes. Apoptosis (programmed cell death) plays a very important role in the development of the vertebrate embryo. The zebrafish (Danio rerio) has become a useful and ideal model in molecular developmental biology for in vivo study on the function of apoptosis in morphogenesis, sex differentiation and so on, and has already been garnering more and more attention. At present, much progress has been made regarding apoptotic pathways in zebrafish development. Caspases and other regulatory apoptotic genes have been cloned successfully. Moreover, transgenic zebrafish embryos have been induced to undergo apoptosis in vivo to study apoptotic signaling pathways and the abnormal morphological changes during embryogenesis. Transgenic zebrafish has provided a powerful tool for illuminating the interaction between regulatory apoptotic genes and vertebrate development.

[Screening and detecting of proteins interacting with mPem]

mPem, a homeobox gene, is expressed in a time and stage specific manner during murine ontogeny. Pem transcripts are abundant in 7- and 8-day mouse embryos, but decrease precipitously thereafter. On Day 9 they become abundant in placenta and yolk sac, persisting there until parturition. Although Pem transcripts are not detectable in most of adult tissues, they are present in reproductive system such as testis, epididymis and ovary. This indicates a important role for Pem during embryogenesis and reproductive development. To study the function of mPem protein, we used a GAL4 based yeast two-hybrid assay to screen a 7-day mouse embryo library with full-length of mPem. 3 proteins were found interacting with mPem protein. One of theses is Mdfic. We confirmed the interaction between mPem and Mdfic in yeast and in vitro. Mdfic, MyoD family inhibitor domain containing, encodes the myoD family inhibitor domain (I-mfa domain). The interaction between mPem and Mdfic suggested they maybe form the transcriptional regulator complex to regulate embryo differentiation.

Interaction of mouse Pem protein and cell division cycle 37 homolog

Mouse Pem, a homeobox gene, encodes a protein consisting of 210 amino acid residues. To study the function of mouse Pem protein, we used the yeast two-hybrid system to screen the library of 7-day mouse embryo with full-length mouse Pem cDNA. Fifty-two colonies were obtained after 1.57 x 10(8) colonies were screened by nutrition limitation and beta-galactosidase assay. Seven individual insert fragments were obtained from the library, and three of them were identified, one of which was confirmed to be the cell division cycle 37 (Cdc37) homolog gene by sequencing. The interaction between mouse Pem and Cdc37 homolog was then confirmed by glutathione S-transferase pull-down assay, and the possible interaction model was suggested.

Construction of an effective m1 GS ribozyme targeting HCMV UL97 mRNA segment in vitro

A sequence-specific M1GS ribozyme (M1-T3) was constructed by covalently linking an oligonucleotide (guide sequence,GS) to the 3' terminus of M1 RNA ,the catalytic subunit of RNase P from Escherichia coli. The engineered ribozyme is targeted to the mRNA sequence encoding a protein kinase (UL97) of HCMV and could effectively cleave the mRNA segment in vitro. Further studies about the significance of some structural elements in the M1 GS (e.g. the 3' CCA tail sequence and a bridge sequence between the 3' terminus of M1 RNA and the 5' terminus of the GS) were carried out. The results showed that the bridge sequence of 88 nucleotides in a mutated M1 GS (i.e. M1-T3*) dramatically increased the cleavage activity to the substrate in vitro. Moreover, the 3'CCA tail sequence was confirmed to be a necessary element for the cleavage activity of M1 GS ribozyme. These data we got in the study will help in understanding the interaction between the M1 GS RNA and its substrate,and will markedly facilitate the research of a general gene targeting agent for anti-HCMV applications.

Generation and characterization of C305, a murine neutralizing scFv antibody that can inhibit BLyS binding to its receptor BCMA

B-lymphocyte stimulator (BLyS) is a member of the tumor necrosis factor (TNF) family and a key regulator of B cell response. Neutralizing single-chain fragment variable (scFv) antibody against BLyS binding to its receptor BCMA has the potential to play a prominent role in autoimmune disease therapy. A phage display scFv library constructed on pIII protein of M13 filamentous phage was screened using BLyS. After five rounds of panning, their binding activity was characterized by phage-ELISA. Nucleotide sequencing revealed that at least two different scFv gene fragments (C305 and D416) were obtained. The two different scFv gene fragments were expressed to obtain the soluble scFv antibodies, then the soluble scFv antibodies were characterized by means of competitive ELISA and in vitro neutralization assay. The results indicated that C305 is the neutralizing scFv antibody that can inhibit BLyS binding to its receptor BCMA.

In vitro construction of effective M1GS ribozymes targeting HCMV UL54 RNA segments

Seven sequence-specific ribozymes (M1GS RNAs) derived in vitro from the catalytic RNA subunit of Escherichia coli RNase P and targeting the mRNAs transcribed by the UL54 gene encoding the DNA polymerase of human cytomegalovirus were screened from 11 ribozymes that were designed based on four rules: (1) the NCCA-3' terminal must be unpaired with the substrate; (2) the guide sequence (GS) must be at least 12 nt in length; (3) the eighth nucleotide must be U, counting from the site -1; and (4) around the cleavage site, the sites -1/+1/+2 must be U/G/C or C/G/C. Further investigation of the factors affecting the cleavage effect and the optimal ratio for M1GS/substrate was carried out. It was determined that the optimal ratio for M1GS/substrate was 2:1 and too much M1GS led to substrate degrading. As indicated above, several M1GS that cleaved HCMV UL54 RNA segments in vitro were successfully designed and constructed. Our studies support the use of ribozyme M1GS as antisense molecules to silence HCMV mRNA in vitro, and using the selection procedure as a general approach for the engineering of RNase P ribozymes.

In Vitro Construction of Effective M1GS Ribozymes Targeting HCMV UL54 RNA Segments

Seven sequence-specific ribozymes (M1GS RNAs) derived in vitro from the catalytic RNA subunit of Escherichia coli RNase P and targeting the mRNAs transcribed by the UL54 gene encoding the DNA polymerase of human cytomegalovirus were screened from 11 ribozymes that were designed based on four rules: (1) the NCCA-3′terminal must be unpaired with the substrate; (2) the guide sequence (GS) must be at least 12 nt in length; (3) the eighth nucleotide must be U, counting from the site –1; and (4) around the cleavage site, the sites –1/+1/+2 must be U/G/C or C/G/C. Further investigation of the factors affecting the cleavage effect and the optimal ratio for M1GS/substrate was carried out. It was determined that the optimal ratio for M1GS/substrate was 2:1 and too much M1GS led to substrate degrading. As indicated above, several M1GS that cleaved HCMV UL54 RNA segments in vitro were successfully designed and constructed. Our studies support the use of ribozyme M1GS as antisense molecules to silence HCMV mRNA in vitro, and using the selection procedure as a general approach for the engineering of RNase P ribozymes.

[Progress on cis-acting regulatory elements in nonsense-mediated mRNA decay]

In eukaryotic cells, nonsense-mediated mRNA decay (NMD) is an effective mRNA surveillance mechanism that detects and degrades mRNAs with premature termination codons ( PTC) and protects cells from the potentially deleterious effects of truncated proteins. Some cis-acting regulatory elements have been reported involving in NMD. They are PTC presence, PTC recongnation by downstream elements that termed as downstream sequence element (DSE) in yeast and primarily exon-exon junction ( EEJ) in mammalian cells, stabilizer sequence (STE) inactivation the NMD, and other sequences correlated with NMD such as extended poly (A) in 3' UTRs,upstream open reading frame (uORF) located in 5' UTR and programmed -1 ribosomal frameshift (-1 PRF). Progress on cis-acting regulatory elements in nonsense-mediated mRNA decay was reviewed in this paper.

[Genetic mutations of homocysteine metabolism related enzymes in patients with ischemic stroke]

To study genetic mutations of methylenetetrahydrofolate reductase (MTHFR) C677T and cystathionine-beta-synthase (CBS) T833C related to homocysteine metabolism in patients with ischemic stroke, the MTHFR gene C677T gene mutation and the CBS T833C gene mutation were detected by PCR-RFLP or ARMS method in 74 patients with ischemic stroke and 83 normal people for control. Results showed that the frequencies of MTHFR T homogenetic type (2.7%) , heterogenetic type (51.4%) and T allele (28.4%) in ischemic group were higher than those in control group (1.2%, 39.8% and 21.1%, respectively). The frequencies of CBS C homogenetic type (13.5%) and C allele (43.9%) in ischemic group were higher than those in control group (6.0% and 38.0%, respectively). Multiple Logistic Regression analysis showed that together with the T allele in MTHFR, the C allele in CBS and age were related to ischemic stroke (P<0.05). The odds ratios (OR) of the T allele in MTHFR C677T and the C allele in CBS T833C were 1.74 (95%CI 1.06-2.86) and 1.73 (95%CI 1.07-2.81) respectively. The study revealed that the genetic mutations of MTHFR C677T, CBS T833C,were related with the ischemic stroke. The genetic mutations of MTHFR C677T and CBS T833C may be genetic factors for ischemic stroke.

[Role of analytical chemistry in the development of new drugs]

In this paper, the role of analytical chemistry in drug research, its development and some basic research related to developing new drugs are concisely discussed, including the establishment of quality control standards, finger prints of natural medicine products, resolution of chiral compounds and drug metabolism studies. The incorrect point of view of some people on pharmaceutical analysis is mentioned and the indispensability of this discipline in drug research and development is also emphasized.

[In vitro metabolic studies of the novel anti-anxietic drug AF-5 and its metabolites in human liver microsome incubation system]

AIM

To study the metabolism of a novel anti-anxietic drug AF-5 and its metabolites (I, II) in human liver microsome incubation system.

METHODS

Human liver microsomes were prepared, the enzyme activity was determined to be 8.79 mg.mL-1 by Lowry's method. The human liver microsome incubation system consisted of: human liver microsomes 2 mg.mL-1, glucose-6-phosphate (G-6-P) 0.01 mmol.mL-1, glucose-6-phosphate dehydrogenase (G-6-PDH) 1 U.mL-1, magnesium chloride (MgCl2) 4.0 mumol.mL-1, coenzyme II in oxidized form (NADP) 0.5 mumol.mL-1, and coenzyme I in reduced form (NADH) 1.0 mumol.mL-1. Two milligrams of AF-5 solubilized by Tween 80 was then added, the mixture was diluted to 5 mL with Tris-HCl solution and the mixture was incubated in a 37 degrees C water bath with shaking. Oxygen was passed over the liquid surface for 0.5 min every 20 minutes. The incubation was carried out for 40 min and 100 min respectively. Three volumes of ethyl ether were added to stop the metabolism, and more ethyl ether was used to extract the metabolites for 3 times. The ether extracts were pooled together, dried with anhydrous sodium sulfate, then evaporated to dryness. The residue was dissolved in 0.5 mL n-hexane and analyzed by GC/MS under the following conditions: 150 degrees C (1 min)[formula: see text]180 degrees C (1 min)[formula: see text]260 degrees C (2 min), in the total ion current mode, EI: 70 eV, interface temperature: 250 degrees C, ion source temperature: 200 degrees C.

RESULTS

Two major metabolites were found and identified in this incubation system, and demonstrated that the in vitro metabolic pathway was that the carbon 4 was first oxidized to hydroxyl group, then further oxidized to a carbonyl group.

CONCLUSION

In human liver microsome incubation system AF-5 was completely metabolized in 100 min to the hydroxy derivative I and carbonyl derivative II, with hydroxymetabolite as the major metabolite. Metabolite I was further transformed to metabolite II, which was not metabolized any further by the human liver microsomes.

[The in vitro metabolism of hainanensine derivative HH07A by rat liver microsomes]

The metabolism of hainanensine derivative HH07A has been studied in vitro with rat microsomes. A method of HPLC-DAD was developed for screening the metabolites from the microsomal incubation system. Two metabolites were found according to their UV spectra. One of them was extracted and purified with preparative HPLC and TLC, its chemical structure was identified by UV, IR, MS and NMR.

[Study on the structure of epimerides of cycloclausenamide]

AIM

To study the structures of the epimerides of cycloclausenamide.

METHODS

The structures of compound I, extracted from Clausena lansium (Lour.) Skeels, and synthesized compound III were determined by single crystal X-ray diffraction analysis. The stereo-structures of compound II and IV were also built up through Tripos force field based on crystal structures of compound I and III.

RESULTS

The molecular formula and molecular weight were found to be C18H17O2N and 279.34 respectively. Compound I crystallized in monoclinic system, space group P2(1) with a = 0.5928(1), b = 1.5014(1), c = 1.6190(1) nm, V = 1.4410(3) nm3, Z = 4, Dx = 1.288 g.cm-3, Rf = 0.075, Rw = 0.073(w = 1/sigma 2|F|), S = 3.983; compound III crystallized in triclinic system, space group P1 with a = 0.5667(1), b = 1.2934(1), c = 2.1119 (1) nm, alpha = 102.17(1), beta = 90.25(1), gamma = 102.65(2) degrees, V = 1.4770(5) nm3, Z = 4, Dx = 1.224 g.cm-3, Rf = 0.047, Rw = 0.051(w = 1/sigma 2|F|), S = 0.467.

CONCLUSION

These results showed that compound I and III both are cycloclausenamide except that the directions of the phenyl group on C6 are different. Cycloclausenamide can form 4 pairs of epimerides but the directions of the phenyl group does not affect their energy in free state.

Production, purification, and characterization of an intracellular aflatoxin-detoxifizyme from Armillariella tabescens (E-20)

Some Armillariella tabescens (E-20) multienzymes have previously been reported to present detoxifying activities against aflatoxins. In this paper, we describe the isolation purification of an intracellular enzyme, named aflatoxin-detoxifizyme, which exhibited detoxification activity on aflatoxin B(1) (AFB(1)). This aflatoxin-detoxifizyme exhibited a specific activity of 7.09 nmol min/mg at pH 6.0 and 28 degrees C. The apparent molecular mass was 51.8 kDa as determined by SDS-PAGE. The isoelectric point was estimated to be 5.4 and optimum activity for the enzyme was found at pH 6.8 and 35 degrees C. The activity of the purified enzyme was confirmed by Ames test.

[Cloning and expression of a synthetic gene encoding magainin-melittin hybrid peptide in Escherichia coli and studies on its antibacterial activity]

A hybrid peptide gene was designed and synthesized. Its encoding peptide is constructed from residues 3-14 of magainin and residues 1-13 of melittin. The MA-E gene was cloned into plasmids pUC18 and pBV220. By DNA sequencing, the whole sequences of this gene is confirmed to be correct. The recombinant plasmid pBMA-E was expressed in E. coli DH5 alpha. A gene product band can be seen with Tricine-SDS-PAGE. The MA-E hybrid peptide was purified by immobilized metal affinity chromatography. Bioactivity assay was carried out in liquid turbidity method. The bactericide value to E. coli K12D31 is 0.182.

Significant down-regulation of alpha-albumin in human hepatoma and its implication

The potential association of alpha-albumin (ALF) with hepatocellular carcinoma (HCC) was investigated. Expression of ALF was significantly reduced in HCC tumor tissue as compared with the paired peritumor tissue from 16 patients and in four HCC cell lines as compared with normal hepatocytes. ALF mRNA was also down-expressed in circulating HCC cells compared to circulating normal hepatocytes. The proliferation of Hep3B cells was inhibited by over-expression of ALF. Taken together, ALF is significantly down-regulated in HCC, and this might facilitate the proliferation of HCC. Thus, detection of ALF mRNA, in addition to that of alpha-fetoprotein (AFP) mRNA, might help to distinguish normal or malignant hepatocytes in peripheral blood.

[Preparation and evaluation of polyvinyl pyrrolidone-coated columns based on sol-gel chemistry for capillary electrophoresis]

Polyvinyl pyrrolidone(PVP) coating techniques based on sol-gel chemistry was investigated in this article. Multiple-step coating and single-step coating methods were developed and the coating conditions(molar ratios of MAPS to 0.1 mol/L HCl, reaction times and concentration of PVP) were selected. Electroosmosis mobility and column efficiency were used as the evaluating parameters for coated capillary columns. For multiple-step coating, the optimal sublayer sol solution was obtained by adding 0.1 mol/L hydrochloric acid to MAPS(molar ratio, 1:1) and reacted at room temperature for 2 hours. The best PVP mass concentration was 40 g/L in alcohol. For single-step coating, the sol-gel solution was obtained by mixing the following ingredients: (a)MAPS, (b) 8% PVP alcohol solution and (c) 0.1 mol/L hydrochloric acid in 1:1 molar ratio to MAPS. The mixture was kept at room temperature for 2 hours. Proper amounts of 100 g/L ammonium persulfate and 10% (V/V) N, N, N', N'-tetramethylethylenediamine were then added. The mixture was mixed ultrasonically, then centrifuged at 4,000 r/min for 5 min. The upper clean sol-gel solution was transferred into another clean vial for coating capillary column. The reproducibility of migration times and efficiencies of single-step-coated capillary was better than that of multiple-step-coated capillary. Single-step-coating method was very effective and easy. It can fit the needs in experimental work. Coating techniques based on sol-gel chemistry are prospective but still need to be further developed.

[The function of T7 promoter as cis-acting elements for polymerase II in eukaryotic cell]

Using the chlorampheniol acetyltransterase gene as reporter, the function of phage T7 promoter in mammalian cells was studied by inhibition of transcription with alpha-amanitin. The experiment proved that the reporter under T7 promoter was transcribed by RNA polymerase II. Competitive electropho retic mobility shift assay (CEMSA) with TATA box, CAAT box, GC box and octamer showed that the TATA box was competitive molecular for synthetic T7 promoter. It is possible that T7 promoter is bound with TF II D transcription factor. The TATA box and octamer were inserted into Pvu II site upstream from the T7 promoter of pT7CAT. Two recombinant plasmids, pT7TATACAT and pT7OCTCAT, were constructed and transfected into CHO cells. CAT-activity test showed that T7 promoter strength was increased by octamer factor, not by TATA box. These results suggested that T7 promoter functions as cis-acting elements of RNA polymerase II transcriptional system in eucaryotic cells.

[A simple method for preparing reversed-phase electrochromatographic column and its evaluation]

The packed column was prepared with a simple method by combination of vacuum filling and pressure compressing. The reproducibility of efficiency and retention time was evaluated. The mixture of thiourea and three aromatic compounds was used. RSD values of retention time were smaller than 2.2% and RSD values of efficiency were smaller than 7.5%. The influence of voltage, phosphate concentration, acetonitrile volume fraction and column temperature on the electroosmotic flow and capacity factor of neutral compounds was investigated. Acetonitrile concentration had significant effect on the electroosmotic flow and capacity factor of neutral compounds. High concentration of acetonitrile improved the elution ability. Low concentration of acetonitrile improved the resolution. Voltage, phosphate concentration, and column temperature also had effects on the electroosmotic flow and capacity factor of neutral compounds, but the effects were smaller than the concentration of acetonitrile. These results gave a guide to select separation conditions in capillary reversed-phase electrochromatography.

Identification of alternative splicing variants of the beta subunit of human Ca(2+)/calmodulin-dependent protein kinase II with different activities

The beta subunit of human Ca(2+)/calmodulin-dependent protein kinase II (beta CaMKII) was identified by searching through an expressed sequence tag database and rapid amplification of cDNA 5'-ends and was assigned to chromosome 7. Reverse transcription-polymerase chain reaction and sequencing analysis identified at least five alternative splicing variants of beta CaMKII (beta, beta6, betae, beta'e, and beta7) in brain and two of them (beta6 and beta7) were first detected in any species. When expressed in HEK 293 cells, the Ca(2+)/calmodulin-dependent kinase activity of beta7, the shortest variant, was much lower than that of either beta (the longest one) or betae (the medium one), suggesting possible regulation of beta CaMKII activity by alternative splicing.

Identification of a human brain-specific isoform of mammalian STE20-like kinase 3 that is regulated by cAMP-dependent protein kinase

A novel isoform of mammalian STE20-like kinase 3 (MST3) with a different 5' coding region from MST3, termed MST3b, was identified by searching through expressed sequence tag data base and obtained by rapid amplification of cDNA 5'-ends. MST3b was assigned to the long arm of human chromosome 13, D13S159-D13S280, by use of the National Center for Biotechnology Information sequence-tagged sites data base. Reverse transcription-polymerase chain reaction and Northern blot analysis with a probe derived from 5' distinct sequence of MST3b revealed that the expression of MST3b mRNA is restricted to the brain, in contrast to ubiquitous distribution of MST3 transcript. Western analysis confirmed the brain-specific expression of MST3b protein. In situ hybridization of rat brain sections with a MST3b-specific probe indicated that MST3b is widely expressed in different brain regions, with especially high expression in hippocampus and cerebral cortex. When expressed in human embryonic kidney 293 (HEK293) cells, MST3b effectively phosphorylated myelin basic protein, as well as undergoing autophosphorylation. Interestingly, expression of MST3, but not MST3b, in HEK293 cells was able to activate the endogenous p42/44 mitogen-activated protein kinase (MAPK) up to 4-fold, whereas neither isoform activated p38 MAPK under the same conditions. Further experiments demonstrated that MST3b, but not MST3, was effectively phosphorylated by activation of cyclic AMP-dependent protein kinase (PKA) in both in vivo and in vitro assays. The mutation of Thr-18 into Ala in MST3b (T18A), a putative PKA phosphorylation site that is absent in MST3, abolished its phosphorylation by PKA. Consequently, expression of the T18A mutant in HEK293 cells led to partial activation of p42/44 MAPK, indicating that MST3b is under the regulation of PKA. Taken together, our data provide evidence that the two isoforms of STE20-like kinase 3 are differentially distributed and regulated.

[The sequence analysis of the 3' end of intron 15 from human LDL receptor gene and its application in the study of gene diagnosis for familial hypercholesterolaemia]

To understand intron 15 of human LDL receptor gene, the DNA fragments from exon 15 to exon 16 and the 3' end of intron 15 were amplified with long chain PCR and anchored PCR. The 3' end of intron 15 was sequenced with Dynalbeads-Streptavidin Solid Phase technique. The sequence analysis showed that the 3' end of intron 15 contained the 3' splicing site and the branch site at 31 nucleotides upstream of the 3' end. Besides the authentic branch site, it is possible that the 3' end of intron 15 contains a cryptic site (GCCTCAC) at 20 nucleotides upstream of the 3' end. The sequences suggest that the PvuII polymorphism at Intron 15 is caused by the T-C substitution. According to the sequences of the 3' end, the new PCR-RFLP protocol for detection of PvuII polymorphism at intron 15 was developed. Using this protocol a representative familial hypercholesterolaemia family was identified with linkage analysis of PvuII polymorphism at intron 15.

[Investigation on in vivo metabolism of n-butyl phthalide]

A GC-MS method for the investigation on the metabolism of n-butyl phthalide (NBP) is described. After oral administration of NBP to rats, urine was collected, hydrolyzed with beta-glucuronidase, extracted and concentrated for TMS derivatization, and then analyzed by GC-MS. HBP and its four oxidative metabolites were determined in 0-24 h, 24-48 h rat urine. The mass spectra of the metabolites and their derivatives were presented and the in vivo metabolic pathway was discussed.

[Investigation on in vivo metabolism of 6-methoxy n-butyl phthalide]

A GC-MS method for the investigation on the metabolism of 6-methoxy n-butyl phthalide (MBP) is described. After oral administration of MBP, the rat urine sample was collected, hydrolyzed with beta-glucuronidase, extracted and concentrated for TMS derivatization, and then analyzed by GC-MS. MBP and its six oxidative metabolites were determined in the 0-24 h rat urine sample. The mass spectra of the metabolites and their derivatives were presented and the in vivo metabolic pathway was discussed.

Carboxyl terminal of rhodopsin kinase is required for the phosphorylation of photo-activated rhodopsin

Human rhodopsin kinase (RK) and a carboxyl terminus-truncated mutant RK lacking the last 59 amino acids (RKC) were expressed in human embryonic kidney 293 cells to investigate the role of the carboxyl terminus of RK in recognition and phosphorylation of rhodopsin. RKC, like the wild-type RK, was detected in both plasma membranes and cytosolic fractions. The C-terminal truncated rhodopsin kinase was unable to phosphorylate photo-activated rhodopsin, but possesses kinase activity similar to the wild-type RK in phosphorylation of small peptide substrate. It suggests that the truncation did not disturb the gross structures of RK catalytic domain. Our results also show that RKC failed to translocate to photo-activated rod out segments. Taken together, our study demonstrate the carboxyl terminus of RK is required for phosphorylation of photo-activated rhodopsin and strongly indicate that carboxyl-terminus of RK may be involved in interaction with photo-activated rhodopsin.

Suppression of phospholipase C blocks Gi-mediated inhibition of adenylyl cyclase activity

The potential effect of inhibition of phospholipase C on the response of Gi-coupled receptors was investigated in neuroblastoma x glioma hybrid (NG108-15) cells. The phospholipase C specific inhibitor 1-[6-((17beta-3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl]-1H -pyrrole-2,5-dione (U73122), which did not affect basal and forskolin-stimulated adenylyl cyclase activities, time- and dose-dependently blocked delta-opioid receptor-mediated inhibition of adenylyl cyclase activity, the EC50 (0.5 microM) of which was consistent with that for inhibition of bradykinin-dependent phospholipase C activation (EC50 = 1 microM). U73122 treatment also blocked functional responses of m4 muscarinic receptor and alpha2-adrenoceptor in NG108-15 cells and three opioid receptors (mu, delta and opioid receptor-like receptor (ORL1)) in human neuroblastoma SK-N-SH cells. 1-[6-((17Beta-3-Methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl]-2, 5-pyrrolidinedione (U73343), an inactive analog of U73122, did not show any effect, which suggests that the blockade by U73122 of Gi-coupled receptor-mediated signaling is probably mediated through inhibition of phospholipase C, although a possible direct modification of G proteins can not be excluded. Furthermore, treatment with U73122 but not U73343 blocked the GTP-induced inhibition of adenylyl cyclase, indicating blockade at the level of Gi proteins.

Functional expression of opioid receptor-like receptor and its endogenous specific agonist nociceptin/orphanin FQ during mouse embryogenesis

Expression of opioid receptor-like receptor (ORL1) and its endogenous peptide agonist nociceptin/orphanin FQ (N/OFQ) during mouse embryogenesis have been investigated. Transcripts of ORL1 and N/OFQ were detected by RT-PCR in mouse brain of day 8 embryo (E8) and the expression continued afterwards. Northern blot analysis revealed abundant expression of ORL1 at postnatal day 1 (P1) and N/OFQ at E17 and P1 in the brain but none was detected in other embryonic tissues. The presence of functional ORL1 in mouse embryonic brain was also confirmed by specific binding of [3H] N/OFQ (kd = 1.3 +/- 0.5 nM and Bmax = 72 +/- 9 fmol/mg protein) as well as by N/OFQ-stimulated G protein activation.

Retardation of pain development: a case of recovery from congenital insensitivity to pain

Congenital analgesia is a rare genetic disorder. We report here that a 12-year-old boy was able to recover from congenital insensitivity to pain. Neurological examinations revealed that there was a 'stocking' distribution of pain decrement on the lower extremities under the patient's knee joints. Magnetic Resonance Imaging (MRI) of his brain showed gyrus thinning with sulcus widening at both sides of the parietal lobe. Southern blot hybridization probed with cDNAs of various opioid receptors did not detect any significant abnormality. Our results suggest that this rare case may not be genetically determined.