Transmission disequilibrium test provides evidence of association between promoter polymorphisms in 22q11 gene DGCR14 and schizophrenia

Recent research has suggested that the DiGeorge syndrome critical region gene 14 (DGCR14) exhibits activity differences of more than 1.5 fold between the haplotypes of the variants in the promoter region. DGCR14 is located at 22q11.21, an acknowledged region for susceptibility to schizophrenia. To test the hypothesis that DGCR14 may be involved in the etiology of the disease, we carried out a family-based association study between the reported functional markers and schizophrenia in 235 Chinese Han trios. We found significant evidence of preferential transmission of the promoter variants of DGCR14 across all the trios (Best p-value = 0.00038, Global p-value = 0.0008). The positive results have suggested that DGCR14 is likely to play an important role in the etiology of schizophrenia in the Chinese Han population.

Islet autoimmunity and genetic mutations in Chinese subjects initially thought to have Type 1B diabetes

AIMS

To explore the contribution of islet autoimmunity and genetic mutations in Chinese patients initially thought to have Type 1B diabetes.

METHODS

A group of 33 Chinese patients with newly diagnosed Type 1B diabetes, were identified by the absence of autoantibodies to glutamic acid decarboxylase (GAD), IA-2, insulin, thyroid globulin or thyroid peroxidase, or high-risk HLA-DQ haplotypes. The cohort was further characterized by measurement of autoantibodies to carboxypeptidase H (CPH) and SOX13 using radioligand assays, and testing for genetic mutations associated with MODY3/MODY6 and mitochondrial diabetes. Mutations of HNF-1alpha (MODY3) and neuroD1/beta2 (MODY6) genes were screened using the single-strand conformation polymorphism (SSCP) technique and sequencing. Mitochondrial DNA mutations were analysed with polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

RESULTS

Within the cohort, we found one patient with a novel mutation, R321H (CGC-->CAC) in exon 5 of the HNF-1alpha gene, one with ND1 mt3316 G-->A mutation in mitochondrial DNA, five with Ala45Thr polymorphisms in the neuroD1/beta2 gene, and two patients with autoantibodies to SOX13.

CONCLUSIONS

Some of the Chinese patients originally thought to have Type 1B diabetes do have other evidence of islet autoimmunity and genetic mutations involved in the underlying aetiology. This suggests that more rigorous screening for these conditions is needed before classifying subjects as having Type 1B diabetes.

Kojic acid production in an airlift bioreactor using partially hydrolyzed raw corn starch

In a culture of Aspergillus oryzae MK-107-39 in a 3-l airlift bioreactor, kojic acid was not produced when glucose/wheat germ medium (GM1) was used. However, when a jar fermentor was used, the kojic acid yield was high. A suitable medium for culture in an airlift bioreactor consisting of partially hydrolyzed corn starch and a small amount of corn steep liquor (CSL) (SM1) was selected. In the cultivation in the airlift bioreactor using SM1, nearly 40 g/l of kojic acid was produced, which was the same as the amount produced in the jar fermentor containing GM1. The optimum aeration rate for the airlift bioreactor was 2.0 vvm (0.66 cm/s of superficial linear velocity (Vs)). The cost of SM1 using the airlift bioreactor was reduced to 40% that of GM1 using the jar fermentor. Furthermore, the energy cost of kojic acid production using SM1 in the airlift bioreactor was less than one-fourth of that for the jar fermentor using GM1.

Optimal Cutoff Point of Glutamate Decarboxylase Antibody Titers in Differentiating Two Subtypes of Adult-Onset Latent Autoimmune Diabetes

The optimal cutoff point of glutamate decarboxylase antibody (GAD-Ab) titers for differentiating two latent autoimmune diabetes (LADA) subtypes remains unclear. One hundred and forty-five GAD-Ab-positive patients screened from phenotypic type 2 diabetes were diagnosed as LADA. The clinical features were compared among LADA patients with different GAD-Ab titers. The receiver-operating characteristic (ROC) curve was used to evaluate the diagnostic value of GAD-Ab titers and to define the optimal cutoff point. The heterogeneity of clinical features in LADA could be discriminated by five GAD-Ab titers, with maximal differences at the titer of 175 U/mL. The ROC curve analysis showed that the optimal cutoff point for discriminating two LADA subtypes was at the titer of 175 U/mL, with sensitivity and specificity of 54.5% and 92.1%, respectively. These findings demonstrated that the two clinically distinct subtypes of LADA can be optimally discriminated by the GAD-Ab titers.

Hertz-Level Measurement of the Optical Clock Frequency in a Single 88Sr+ Ion

The frequency of the 5s 2S(1/2)-4d 2D(5/2) electric quadrupole clock transition in a single, trapped, laser-cooled 88Sr+ ion has been measured by using an optical frequency comb referenced to a cesium fountain primary frequency standard. The frequency of the transition is measured as 444,779,044,095,484.6 (1.5) hertz, with a fractional uncertainty within a factor of 3 of that of the cesium standard. Improvements required to obtain a cesium-limited frequency measurement are described and are expected to lead to a 88Sr+ optical clock with stability and reproducibility exceeding that of the primary cesium standard.

Measurement of the electric quadrupole moment of the 4d2D5/2 level in 88Sr+

The quadrupole moment of the 4d (2)D(5/2) level in 88Sr+ has been measured to be 2.6(3)ea(2)(0), where a(0) is the Bohr radius and e the elementary charge. A single laser-cooled strontium ion was confined in an end cap trap with a variable dc quadrupole potential, and measurements were made on the 5s (2)S(1/2)-4d (2)D(5/2) transition at 674 nm using a femtosecond optical frequency comb. This work shows that measurements of the unperturbed 88Sr+ transition frequency with sub-Hz uncertainty are possible and is important in understanding the reproducibility of ion trap optical frequency standards.

Endoscopic third ventriculostomy in the management of obstructive hydrocephalus: an outcome analysis

Object. The purpose of this paper is to elucidate the safety and efficacy of, and indications and outcome prognosis for endoscopic third ventriculostomy (ETV) in 58 patients with obstructive hydrocephalus.

Methods. Between September 1999 and April 2003, 58 ETVs were performed in 58 patients with obstructive hydrocephalus (36 male and 22 female patients) at the authors' institution. The ages of the patients ranged from 5 to 67 years (mean age 35 years) and the follow-up period ranged from 3 to 41 months (mean duration of follow up 24 months). Patients were divided into four subgroups based on the cause of the obstructive hydrocephalus: 21 with intracranial tumors; 11 with intracranial cysts; 18 with aqueductal stenosis; and eight with intracranial hemorrhage or infection. Both univariate and multi-variate statistical analyses were performed to assess the prognostic relevance of the cause of the obstructive hydrocephalus, early postoperative clinical appearance, and neuroimaging findings in predicting the result of the ETV.

The survival rate was 87% at the end of the 1st year and 84% at the end of the 2nd year post-ETV. One month after ETV an overall clinical improvement was observed in 45 (77.6%) of 58 patients. If we also consider the successful revision of ETV in two patients, a success rate of 78.3% (47 of 60 patients) was reached. The ETV was successful in 17 (81%) of 21 patients with intracranial tumors, nine (82%) of 11 with cystic lesions, 16 (88.9%) of 18 with aqueductal stenosis, and three (38%) of eight with intracranial hemorrhage or infection. A Kaplan—Meier analysis illustrates that the percentage of functioning ETVs stabilizes between 75 and 80% 1 year after the operation. In a comparison of results 1 year after ETV, the authors found that the aqueductal stenosis subgroup had the highest proportion of functioning ETV (89%). The proportions of the tumor and cyst subgroups were 84 and 82%, respectively, whereas the proportion was only 50% in the ventriculitis/intracranial hemorrhage subgroup (strata log-rank test: χ2 = 7.93, p = 0.0475).

In the present study, ETV failed in eight patients (13.8%) and the time to failure after the procedure was a mean of 3.4 months (median 2 months, range 0–8 months). The logistic regression analysis confirmed an early postoperative improvement (within 2 weeks after ETV, significance [Sig] of log likelihood ratio [LLR] < 0.0001) and a patent stoma on cine phase—contrast magnetic resonance (MR) images (Sig of LLR = 0.0002) were significant prognostic factors for a successful ETV. The results demonstrated the multivariate model (B = − 53.7309, standard error = 325.1732, Wald = 0.0273, Sig = 0.8688) could predict a correct result in terms of success or failure from ETV surgery in 89.66% of observed cases. The Pearson chi-square test demonstrated that little reliance could be placed on the finding of a reduced size of the lateral ventricle (χ2 = 5.305, p = 0.07) on neuroimaging studies within 2 weeks after ETV, but it became a significant predictive factor at 3 months (χ2 = 8.992, p = 0.011) and 6 months (χ2 = 10.586, p = 0.005) post-ETV. Major complications occurred in seven patients (12.1%), including intraoperative venous bleeding in three, arterial bleeding in one, and occlusion of the stoma in three patients. The overall mortality rate was 10.3% (six patients). One of these patients died of pulmonary infection and another of ventriculitis. Four additional patients died of progression of malignant tumor during the follow-up period.

Conclusions. The results indicate that ETV is a most effective treatment in cases of obstructive hydrocephalus that is caused by aqueductal stenosis and space-occupying lesions. For patients with infections or intraventricular bleeding, ETV has considerable effects in selected cases with confirmed CSF dynamic studies. Early clinical and cine phase—contrast MR imaging findings after the operation play an important role in predicting patient outcomes after ETV. The predictive value of an alteration in ventricle size, especially during the early stage following ETV, is unsatisfactory. Seventy-five percent of ETV failures occur within 6 months after surgery. A repeated ventriculostomy should be considered to be a sufficient treatment option in cases in which stoma dysfunction is suspected.

Recombinant matrix metalloproteinase-14 catalytic domain induces apoptosis in human osteoblastic SaOS-2 cells

Our study previously showed that estrogen and progesterone stimulated the production of matrix metalloproteinase-14 [MMP-14, or also named membrane type matrix metalloproteinses-1 (MT1-MMP)] in osteoblastic cells. MMP-14 was implied to regulate the function of osteoblasts by degrading bone matrix or growth factors, but the mechanism is unclear. Since MMP-14 plays a role primarily through the catalytic domain, and truncated MMP-14 containing the catalytic domain and lacking transmembrane domain can be secreted into medium by cultured cells, our present study was performed to observe the direct effects of recombinant MMP-14 catalytic domain on cultured human osteoblastic osteogenic sarcoma (SaOS)-2 cells. Our data showed that recombinant MMP-14 catalytic domain activated proMMP-2 secreted into media by SaOS-2 cells, and this process was blocked by ethylenediamine tetraacetic acid (EDTA) treatment. Recombinant MMP-14 catalytic domain inhibited the adhesion of SaOS-2 cells to immobilized type I collagen or fibronectin in a dose-dependent manner, and these effects on SaOS-2 cells were abolished by EDTA. Recombinant MMP-14 catalytic domain induced SaOS-2 cells apoptosis in a dose-dependent manner, and apoptosis-inducing activity of MMP-14 catalytic domain was blocked if it was treated with EDTA. In conclusion, we revealed that recombinant MMP-14 catalytic domain induced SaOS-2 cells apoptosis. We also indirectly showed the activity of MMP-14 catalytic domain to degrade extracellular matrix (ECM) in cultures of SaOS-2 cells through Gelatin Zymograms and adhesion assay. This suggests that since adhesion of cells to ECM serves as a survival mechanism in osteoblasts, the catalytic activity of recombinant MMP-14 catalytic domain on matrix proteins contributes to its apoptosis-inducing activity.

A comparison study of the reference curves of bone mineral density at different skeletal sites in native Chinese, Japanese, and American Caucasian women

To understand the differences among reference curves for bone mineral density (BMD) for Chinese, Japanese, and American Caucasian women, we measured the BMD at the anteroposterior (AP) lumbar spine (L1-L4), lateral lumbar spine (L2-L4), hip (including the femoral neck, trochanter, intertrochanter, Ward's triangle, and total hip), and ultradistal forearm by the dual-energy X-ray absorptiometry (DXA) in a total of 2728 healthy Chinese women, aged 5-96 years. Documented BMD data for Japanese women and device manufacturer's BMD new reference databases (including the NHANES III dataset) for American Caucasian women were also used in this study. The cubic regression model was found to fit best in analyzing the age-associated variations of BMD at various sites in Chinese women, i.e., the equations had the largest coefficient of determination (R2). At the AP/Lat spine, trochanter, intertrochanter, and Ward's triangle, BMD reference curves for Chinese women were lower than those for Japanese or Caucasian women, while at the femoral neck, total hip, and ultradistal forearm, the reference curves for Chinese women were higher than those for Japanese women, with overlaps and crossing of the curves for some age spans in comparing the Chinese and Caucasian women. There were significant differences in the peak BMD (PBMD) at various sites among the Chinese, Japanese, and Caucasian women (P = 0.000). The PBMDs for Chinese women at the lumbar spine and various sites of the hip were 5.7% +/- 2.1% (mean +/- SD, range, 2.7-7.9%) lower than those for Japanese women and 5.1% +/- 2.7% (range, 0.5-7.2%) lower than those for Caucasian women; however, the PBMDs for Chinese women were 26.2% higher than those for Japanese women and 10% higher than those for Caucasian women at the ultradistal forearm. After the PBMD, average T-scores of Chinese women for losses at the AP lumbar spine with increasing age were nearly identical to those for Japanese women, but both were greater than those for Caucasian women. The average T-scores for BMD loss at various sites in Chinese women were higher than those for both Japanese and Caucasian women except at the femoral neck, where the T-scores of Chinese women were exceeded by those of both Japanese and Caucasian women. Estimated from the T-score curve of BMD loss, the age of osteoporosis occurrence at the femoral neck in Chinese women was about 10 years later than that in Japanese or Caucasian women; at the AP spine, Chinese women were similar to Japanese women; at the other sites, the age for occurrence of osteoporosis in Chinese women was about 5-15 years earlier than that in either Japanese or Caucasian women. There are differences in prevalence or odds ratio (OR) of osteoporosis at the same skeletal region for Chinese, Japanese, and Caucasian women aged > or = 50 years or at different skeletal regions in women of the same race. The prevalences of osteoporosis at various regions of the hip in Chinese women are 10.1-19.8% and ORs are 22.0-32.3, of which prevalence at the femoral neck is the lowest (10.1%); the prevalences of osteoporosis in Japanese women are 11.6-16.8% and ORs are 21.1-26.3, of which prevalence at the femoral neck is the lowest (11.6%); and the prevalences of osteoporosis in Caucasian women are 13.0-20.0% and ORs are 19.4-48.9, of which prevalence at the femoral neck is the highest (20%). In conclusion, racial differences in BMD reference curves, prevalences, and risks of osteoporosis at various skeletal sites exist among native Chinese, Japanese, and American Caucasian women.

[Observation on the infectivity of different densities of Plasmodium vivax to Anopheles sinensis]

AIM

To study the infectivity of different densities of P. vivax to An. sinensis.

METHODS

Venous blood samples from 38 volunteers artificially infected with P. vivax of South-Yunnan collected at the time of initial parasitaemia, primary attack and relapse, were used to infect Anopheles sinensis by feeding on parasitaemia blood in vitro. The finding of oocysts in the mid-gut of the mosquito by microscope was taken as criteria of positive infection.

RESULTS

P. vivax in the initial parasitaemia did not infect the mosquito. In the cases of primary attack, when the density of parasite was more than 100/microliter blood, the infectivity and intensity rose with the prolongation of the course of the disease and the increase in the density of the parasite. The infectivity of the P. vivax in the relapse cases was higher than in the primary attack cases, the mosquitoes could be infected at a parasite density of 1/microliter blood. The mosquitoes acquired a higher infection rate, a higher positive rate of mosquito mid-gut and a higher oocyst index in the primary attack cases whose parasite density were higher than 1,000/microliter blood and in the relapse cases whose parasite density were higher than 100/microliter blood.

CONCLUSION

The P. vivax in the period of clinical attack was one of the most dangerous period of the spread of malaria. The cases of relapse were the more dangerous infective sources in malaria transmission.

Two case reports of pituitary adenoma associated with Toxoplasma gondii infection

The involvement of the pituitary in cases of toxoplasmosis has been described in the literature only rarely. This is the first report to describe pituitary adenoma in association with Toxoplasma gondii infection. The two patients were 43 and 19 year old women. Radiological examination revealed tumours in the sellar region. Microscopically, the tumours consisted of small homogeneous polygonal or round cells. Toxoplasma cysts were found among the tumour cells, a finding confirmed by Toxoplasma gondii specific antibody immunohistochemistry. The association between pituitary adenoma and toxoplasma raises the possibility that T gondii might be involved in the development of certain cases of pituitary adenoma.

Congou tea drinking and oesophageal cancer in South China

The study from a large hospital-based case-control for 1248 cases with oesophageal cancer and the same number of controls in South China showed that Congou, a grade of Chinese black tea, may protect against cancers of the oesophagus and reduce the risk of a combination of alcohol drinking and smoking (especially smoking), regardless of temperature when drinking.

[Inhibitory effect of cationic liposome-mediated antisense c-myb oligonucleotide on the growth of glioma]

OBJECTIVE

To aim at demonstrating whether cationic liposome-mediated antisense c-myb oligonucleotide(LipoAON) can inhibit the growth of C6 glioma by intravenous injection.

METHODS

Intracerebral C6 glioma cells were implanted into the left caudal nucleus of forty-eight male Wistar rats. There were four groups: LipoAON(n = 12), antisense c-myb oligonucleotide (AON; n = 12), cationic liposome (Lipo; n = 12), and normal saline (NS; n = 12). Six days after tumor implantation, the above-mentioned drugs were injected into the right femoral veins of the rats respectively. Two days later, the same drugs were injected into the left femoral veins. The appetite, motor and weight of every animal were closely observed during the whole experiment. Six rats of each group were respectively killed 4 days and 10 days after the end of administration. The weight change, pathologic examination and immunohistochemical analysis of c-myb expression of the tumor were completed.

RESULTS

In LipoAON group, the growth of the tumors was significantly inhibited in a short time after treatment and c-myb expression was down-regulated. But in the AON group and Lipo group, the growth of the tumors was not inhibited and c-myb expression was not down-regulated, compared with that in NS group. The inhibitory effect of LipoAON on the tumors rapidly declined with time and c-myb expression was again up-regulated.

CONCLUSION

1. Cationic liposome (LipofectAMINE) as transfection vehicle makes c-myb easily penetrate BBTB and enter the tumor. The technique is simple, safe, highly effective for the transfection of c-mybAON; 2. LipoAON has marked inhibitory effect on the growth of C6 glioma. The AON technical method for inhibiting the expression of c-myb oncogene has a research perspective in the treatment of glioma; 3. The inhibitory effect of LipoAON on the growth of glioma declines with time. The question about how to make c-myb AON have highly effective, sustained and stable expression in the tumor still requires further research.

A novel Notch ligand, Dll4, induces T-cell leukemia/lymphoma when overexpressed in mice by retroviral-mediated gene transfer

Notch receptors mediate cell-fate decisions through interaction with specific ligands during development. The biological role of a novel Notch ligand, Dll4, in mice was explored by reconstituting lethally irradiated mice with bone marrow (BM) cells transduced with Dll4 retroviral vector. White blood cell and lymphocyte counts in Dll4-overexpressing mice were reduced at the early stage of reconstitution but increased significantly at approximately 10 weeks after BM transplantation. BM, spleen, lymph nodes, and peripheral blood of Dll4-overexpressing mice contained predominantly CD4(+)CD8(+) T cells and virtually lacked B cells. The Dll4-overexpressing mice eventually developed a lethal phenotype that was characterized by the progression of a T-cell lymphoproliferative disease (restricted to BM and lymphoid tissues) to transplantable monoclonal T-cell leukemia/lymphoma scattered to multiple organs. Results suggest that the interaction of Dll4 with Notch1 may provide key signals for T-cell development.