Neurocognitive effects of treatment interruption in stable HIV-positive patients in an observational cohort

OBJECTIVE

Prior studies have shown improved neurocognition with initiation of antiretroviral treatment (ART) in HIV. We hypothesized that stopping ART would be associated with poorer neurocognitive function.

METHODS

Neurocognitive function was assessed as part of ACTG 5170, a multicenter, prospective observational study of HIV-infected subjects who elected to discontinue ART. Eligible subjects had CD4 count >350 cells/mm(3), had HIV RNA viral load <55,000 cp/mL, and were on ART (>or=2 drugs) for >or=6 months. Subjects stopped ART at study entry and were followed for 96 weeks with a neurocognitive examination.

RESULTS

A total of 167 subjects enrolled with a median nadir CD4 of 436 cells/mm(3) and 4.5 median years on ART. Significant improvements in mean neuropsychological scores of 0.22, 0.39, 0.53, and 0.74 were found at weeks 24, 48, 72, and 96 (all p < 0.001). In the 46 subjects who restarted ART prior to week 96, no significant changes in neurocognitive function were observed.

CONCLUSION

Subjects with preserved immune function found that neurocognition improved significantly following antiretroviral treatment (ART) discontinuation. The balance between the neurocognitive cost of untreated HIV viremia and the possible toxicities of ART require consideration.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that discontinuing ART is associated with an improvement in 2 neuropsychological tests (Trail-Making Test A & B and the Wechsler Adult Intelligence Scale-Revised Digit Symbol subtest) for up to 96 weeks. Resuming ART was not associated with a decline in these scores for up to 45 weeks.

The rag locus of Porphyromonas gingivalis might arise from Bacteroides via horizontal gene transfer

Porphyromonas gingivalis is regarded as one of the risk factors of periodontitis. P. gingivalis exhibits a wide variety of genotypes. Many insertion sequences (ISs), located in their chromosomes, made P. gingivalis differentiate into virulent and avirulent strains. In this research, we investigated the prevalence of P. gingivalis in the gingival crevicular fluid (GCF) among periodontitis patients from Zhenjiang, China, detected the P. gingivalis rag locus distributions by multiplex polymerase chain reaction (PCR), and analyzed the origin of the P. gingivalis rag locus based on evolution. There were three rag locus variants co-existing in Zhenjiang. The results showed that the rag locus may be associated with severe periodontitis. This work also firstly ascertained that the rag locus might arise, in theory, from Bacteroides sp. via horizontal gene transfer.

Intraspecific functional diversity in hosts and its effect on disease risk across a climatic gradient

The effects of host biodiversity on disease risk may vary greatly depending on host population structure and climatic conditions. Agricultural diseases such as potato late blight, caused by Phytophthora infestans, provide the opportunity to study the effects of intraspecific host diversity that is relatively well-defined in terms of disease resistance phenotypes and may have functional impacts on disease levels. When these systems are present across a climatic gradient, it is also possible to study how season length and conduciveness of the environment to disease may influence the effects of host diversity on disease risk. We developed a simple model of epidemic progress to evaluate the effects on disease risk of season length, environmental disease conduciveness, and host functional divergence for mixtures of a susceptible host and a host with some resistance. Differences in disease levels for the susceptible vs. resistant genotypes shifted over time, with the divergence in disease levels first increasing and then decreasing. Disease reductions from host diversity were greatest for high host divergence and combinations of environmental disease conduciveness and season length that led to moderate disease severity. We also compared the effects of host functional divergence on potato late-blight risk in Ecuador (long seasons), two sites in Peru (intermediate seasons) in El Niño and La Niña years, and the United States (short seasons). There was some evidence for greater disease risk reduction from host diversity where seasons were shorter, probably because of lower regional inoculum loads. There was strong evidence for greater disease reduction when host functional divergence was greater. These results indicate that consideration of season length, environmental conduciveness to disease, and host functional divergence can help to explain the variability in disease response to host diversity.

Modulation of malaria-induced immunopathology by concurrent gastrointestinal nematode infection in mice

We investigated malaria-associated pathology in mice co-infected with Heligmosomoides polygyrus (Hp) and Plasmodium chabaudi AS (Pc). Despite higher peak parasitemia, co-infected wild-type (WT) C57BL/6 mice displayed similar body weight losses, malarial anaemia, and tissue damage but less severe hypothermia and hypoglycaemia, and earlier reticulocytosis than Pc-infected WT mice. Co-infected STAT6(-/-) mice, deficient in nematode-induced Th2 responses, experienced similar peak parasitemias and generally suffered malaria-associated pathology to a similar degree as co-infected WT mice. These data indicate a complex relationship amongst helminths, malaria and host immune responses resulting in modulation of some but not all aspects of malaria-associated pathology.

Tat-modified leptin is more accessible to hypothalamus through brain-blood barrier with a significant inhibition of body-weight gain in high-fat-diet fed mice

Obesity in human was found mainly due to the poor transportation of leptin through brain-blood barrier (BBB), called as leptin resistance. To produce a leptin capable of penetrating BBB, we have added Tat-PTD(9) to the C terminal of leptin to construct a fusion protein. The fusion Tat-leptin and native leptin genes were synthesized by single-step insertion of a polymerase chain reaction and expressed in Escherichia coli BL21 (Rosseta). The expressing products were purified and renatured by Ni-NTA affinity chromatography, and identified by the molecular size in SDS-PAGE gel and by its immunoreactivity to specific antibody with Western-blotting assay. To bio-functionally evaluate the fusion protein, Balb/c mice fed with high-fat diet (HFD) were given Tat-leptin, leptin or saline for 19 days. The immunohistochemical staining showed the increases in positive stains for the leptin in the region of hypothalamus of the HFD mice with either Tat-leptin or leptin as compared to saline group, but the staining intensity and frequency in the group with Tat-leptin were stronger and higher than those in the group with leptin. Furthermore, the most efficiency in preventing the body-weight gain caused by HFD was found in Tat-leptin group among these three groups. These results suggest that Tat-modified leptin may become a great potential candidate for the prevention or therapy of obese patients.

Healthy but not RSV-infected lung epithelial cells profoundly inhibit T cell activation

Background:

Respiratory viruses, including respiratory syncytial virus (RSV), can cause asthma exacerbations and bronchiolitis. Both conditions are associated with enhanced cognate immune responses and inflammation and reduced immune regulation. Lung epithelial cells (LECs) can contribute to antiviral and allergic immune responses while gut epithelial cells can inhibit effector T cell responses. A study was performed to determine whether healthy LECs regulate antigen-specific T cell responses and if this regulation is lost during RSV infection.

Methods:

LA4 cells, a murine LEC line, infected with RSV or primary murine LECs were co-cultured with ovalbumin-specific T cell receptor transgenic CD4+ T cells from DO11.10 mice and ovalbumin-pulsed bone marrow-derived dendritic cells (DC) to assess T cell proliferation by flow cytometry and cytokine production.

Results:

The presence of LECs abrogated DC-induced T cell proliferation and significantly reduced T cell cytokine release. These effects of LECs were predominantly contact-dependent, primarily affected T cells directly and were partly mediated by transforming growth factor β. Soluble factors and DC-mediated effects also contributed to T cell inhibition. RSV infection of LECs reduced their inhibitory capacity in an infection dose-dependent manner. This was independent of proinflammatory cytokines released by infected LECs, but in part due to Toll-like receptor activation and to infection-induced cell death.

Conclusion:

Healthy LECs are potent inhibitors of T cell activation, but this regulatory function is lost after RSV infection. These findings suggest a central role for LECs in maintaining the tolerogenic environment of healthy lungs. Loss of this regulatory capacity after viral infection may allow development of excessive cognate immune responses and pulmonary inflammation.

Integrating Remote Sensing Information Into A Distributed Hydrological Model for Improving Water Budget Predictions in Large-scale Basins through Data Assimilation

This paper investigates whether remote sensing evapotranspiration estimates can be integrated by means of data assimilation into a distributed hydrological model for improving the predictions of spatial water distribution over a large river basin with an area of 317,800 km². A series of available MODIS satellite images over the Haihe River basin in China are used for the year 2005. Evapotranspiration is retrieved from these 1×1 km resolution images using the SEBS (Surface Energy Balance System) algorithm. The physically-based distributed model WEP-L (Water and Energy transfer Process in Large river basins) is used to compute the water balance of the Haihe River basin in the same year. Comparison between model-derived and remote sensing retrieval basin-averaged evapotranspiration estimates shows a good piecewise linear relationship, but their spatial distribution within the Haihe basin is different. The remote sensing derived evapotranspiration shows variability at finer scales. An extended Kalman filter (EKF) data assimilation algorithm, suitable for non-linear problems, is used. Assimilation results indicate that remote sensing observations have a potentially important role in providing spatial information to the assimilation system for the spatially optical hydrological parameterization of the model. This is especially important for large basins, such as the Haihe River basin in this study. Combining and integrating the capabilities of and information from model simulation and remote sensing techniques may provide the best spatial and temporal characteristics for hydrological states/fluxes, and would be both appealing and necessary for improving our knowledge of fundamental hydrological processes and for addressing important water resource management problems.

Candidate genes for obesity revealed from a C57BL/6J x 129S1/SvImJ intercross

OBJECTIVE

To identify the genes controlling body fat, we carried out a quantitative trait locus (QTL) analysis using C57BL/6J (B6) and 129S1/SvImJ (129) mice, which differ in obesity susceptibility after consuming an atherogenic diet.

METHODS

Mice were fed chow until 8 weeks and an atherogenic diet from 8 to 16 weeks; body fatness was measured by X-ray absorptiometry in 528 (B6 x 129) F(2) at 8 and 16 weeks. A high-density genome scan was performed using 508 polymorphic markers. After identifying the genetic loci, we narrowed the QTL using comparative genomics and bioinformatics.

RESULTS

The percentage of body fat was significantly linked to loci on chromosomes (Chr) 1 (22, 68 and 173 Mb), 4 (74 Mb), 5 (73 Mb), 7 (88 Mb), 8 (43 and 80 Mb), 9 (55 Mb), 11 (115 Mb) and 12 (32 Mb); three suggestive loci on Chrs 6 (76 Mb), 9 (30 Mb) and 16 (26 Mb) and two pairs of interacting loci (Chr 2 at 99.8 Mb with Chr 7; Chr 1 at 68 Mb with Chr 11). Comparative genomics narrowed the QTL intervals by 20-57% depending on the chromosome; in most cases, haplotype analysis further narrowed them by about 90%.

CONCLUSIONS

Our analysis identified 15 QTL for percentage of body fat. We narrowed the QTL using comparative genomics and haplotype analysis and suggest several candidate genes: Apcs on Chr 1, Ppargc1a on Chr 5, Ucp1 on Chr 8, Angptl6 on Chr 9 and Lpin1 on Chr 12.

Effects of inoculation strategy and cultivation approach on the performance of microbial fuel cell using marine sediment as bio-matrix

AIMS

To investigate the effects of inoculation strategy and cultivation approach on the performance of microbial fuel cell (MFC).

METHODS AND RESULTS

A dual-chamber sediment fuel cell was set up fed with glucose under batch condition. At day 30, the supernatant consortium was partly transferred and used as inoculum for the evaluation of cultivation approach. Power output gradually increased to 9.9 mW m(-2) over 180 days, corresponding to coulombic efficiency (CE) of 29.6%. Separated biofilms attached anode enabled power output and CE dramatically up to 100.9 mW m(-2) and over 50%, respectively, whereas the residual sediment catalysed MFC gave a poor performance. MFC catalysed by in situ supernatant consortium demonstrated more than twice higher power than MFC catalysed by the supernatant consortium after Fe(OH)(3) cultivation. However, the re-generation of biofilms from the latter largely enhanced the cell performance.

CONCLUSIONS

MFC exhibited a more efficient inducement of electroactive consortium than Fe(OH)(3) cultivation. MFC performance varied depending on different inoculation strategies.

SIGNIFICANCE AND IMPACT OF THE STUDY

This is the first time to study cultivation approach affecting electricity generation. In addition, anodic limitations of mass and electron transfer were discussed through MFC catalysed by sediment-based bio-matrix.

Mucous domains: microchemical heterogeneity in the mucociliary complex of the olfactory epithelium

Access to and clearance of odorants from binding sites on olfactory cilia are regulated by a complex interplay of molecular, physical and cellular factors. These perireceptor events occur primarily in the mucociliary complex. The use of gold-labelled lectinoprobes, one from Limax flavus (LFA) which is specific for terminal sialic acid residues, and one from Datura stramonium (DSA) specific for N-acetylglucosamine residues, demonstrated intricate patterns of binding in mucous domains of the olfactory mucus and ectodomains of the glycocalyx of olfactory cilia. In electron micrographs of Lowicryl-embedded salamander olfactory mucosa, the mucus consisted of an electron-dense domain that lay superficial to an electron-lucent domain; the interface between the two was irregular. A significantly higher density of binding sites for both lectins was present in the superficial than in the deeper domain. The two domains were not homogeneous: there were small electron-lucent domains (hsL) within the superficial electron-dense domain (hsD) that bound a 4.8-fold lower density of gold-labelled DSA than the surrounding matrix, and the olfactory cilia, which project into hsD, were surrounded by an electron-lucent sheath that appeared to be continuous with the deeper domain. Ectodomains of the glycocalyx associated with olfactory cilia exhibited a higher density of binding sites for both LFA and DSA than did either microvilli of sustentacular cells or respiratory cilia. Specificity of the lectinoprobes was confirmed by inhibition of binding with specific sugars or enzymic removal of specific sugar residues. These results demonstrated microchemical heterogeneity of the non-homogeneous mucous domains in olfactory mucus and in the attendant glycocalyx of olfactory cilia based on the differential localization of sialic acid and N-acetylglucosamine sugar residues.

Immature myeloid cell (ImC)- mediated immunosuppression in advanced renal cell cancer (RCC)

10042

Background: RCC affects the immunsystem by inhibiting the process of differentiation of antigen-resenting cells from their myeloid precursors by secreting tumor-derived factors such as VEGF. ImC induce a profound state of immune suppression that foster tumor tolerance by inhibition of tumor specific T cells. In this study, we asked whether increased ImC frequencies can be found in peripheral blood from RCC patients and if ImC frequencies correlated positively with increased levels of tumor-derived serum markers. Methods: ImC frequencies from healthy volunteers and RCC patients were determined by FACS. ImC were isolated by magnetic bead separation techniques and their immunosuppressive activity was determined in IFN-γ ELISPOT analyses, CTL and T-cell proliferation assays. The production of reactive oxygen species by ImC was analyzed utilizing specific probes and inhibitors. Tumor-derived serum markers were quantified by ELISA, enzyme immune assays and cytometric bead arrays. Microarray analyses were performed to identify novel, highly specific ImC markers. Results: RCC patients demonstrate higher ImC frequencies (0.8 - 3.2% of total PBMC) compared to healthy donors. The increased ImC frequencies are positively correlated with serum levels of VEGF, PGE-2, IL-13 and M-CSF in RCC patients and the concentration of byproducts of oxidative burst, including iso-prostane and malondialdehyde, was significantly enhanced. Isolated ImC exhibited profound immunosuppressive effects on CTL and CD4+ T cell response in an antigen specific fashion. Immunosuppression by ImC was mediated by release of ROS, including peroxide and superoxide anions and by generation of nitric oxide radicals as evidenced in functional assays. Results from microarray analyses reveal EP-1, EphA5, and PEX-5 as novel ImC markers. Conclusions: These data suggest that RCC may induce the development of immunosuppressive ImC population through secretion of cytokines such as VEGF, IL-13, M-CSF and PGE-2. Inhibition of specific cytokine activity or the use of differentiating agents may represent strategies to decrease immunosuppressive ImC population. Results from a phase I clinical trial investigating the effects of all-trans retinoic acid (ATRA) on differentiation of ImC in RCC patients will be presented.

No significant financial relationships to disclose.

A comparative survey on alcohol and tobacco use in urban and rural populations in the Huaihua District of Hunan Province, China

Modern Chinese society is comprised primarily of two subgroups-urban and rural subpopulations. However, comparative data regarding alcohol and tobacco use between urban and rural subgroups in China is sparse. An epidemiological survey was conducted in the Huaihua District of Hunan Province of China, and 3,543 urban and 4,294 rural dwellers aged 15-65 years were interviewed. The drinking rates were higher in the urban area (45.9%) than in the rural area (39.6%), whereas the smoking rates were higher in the rural area (35.9%) than in the urban area (28.7%). Rural respondents were more likely to report heavy drinking (Adjusted odds ratio [OR]=1.77) and heavy smoking (Adjusted OR=2.46) than urban populations. Specifically, rural males had higher odds of heavy alcohol and tobacco use than urban males, whereas more urban females were more likely to drink and smoke than rural counterparts. The findings suggest that the status of alcohol and tobacco use varies in the urban and rural area. The heavy alcohol and tobacco consumption among rural populations underscores the need to develop and implement culturally appropriate public health intervention and awareness arising programs especially in rural China.

Angiotensin-(1-7) inhibits angiotensin II-stimulated phosphorylation of MAP kinases in proximal tubular cells

Angiotensin-converting enzyme 2 (ACE2) is a homolog of ACE, which is not blocked by ACE inhibitors. High amounts of ACE2 are present in the proximal tubule, and ACE2 catalyzes generation of angiotensin 1-7 (Ang-(1-7)) by this segment. Ang-(1-7) binds to a receptor distinct from the AT1 or AT2 Ang II receptor, identified as the mas receptor. We studied the effects of Ang-(1-7) on Ang II-mediated cell signaling pathways in proximal tubule. In primary cultures of rat proximal tubular cells, activation of mitogen-activated protein kinases (MAPK) was detected by immunoblotting, in the presence or absence of agonists/antagonists. Transforming growth factor-beta1 (TGF-beta1) was measured by enzyme-linked immunosorbent assay. Ang II (5 min, 10(-7) M) stimulated phosphorylation of the three MAPK (p38, extracellular signal-related kinase (ERK 1/2), and c-Jun N-terminal kinase (JNK)). While incubation of proximal tubular cells with Ang-(1-7) alone did not significantly affect MAPK phosphorylation, Ang-(1-7) (10(-7) M) completely inhibited Ang II-stimulated phosphorylation of p38, ERK 1/2, and JNK. This inhibitory effect was reversed by the Ang-(1-7) receptor antagonist, D-Ala7-Ang-(1-7). Ang II significantly increased production of TGF-beta1 in proximal tubular cells, an effect that was partly inhibited by Ang-(1-7). Ang-(1-7) had no significant effect on cyclic 3',5'-adenosine monophosphate production in these cells. In summary, Ang-(1-7) inhibits Ang II-stimulated MAPK phosphorylation in proximal tubular cells. Generation of Ang-(1-7) by proximal tubular ACE2 could thereby serve a protective role by counteracting the effects of locally generated Ang II.

Activation of Ras/Raf protects cells from melanoma differentiation-associated gene-5-induced apoptosis

Melanoma differentiation-associated gene-5 (mda-5) was the first molecule identified in nature whose encoded protein embodied the unique structural combination of an N-terminal caspase recruitment domain and a C-terminal DExD/H RNA helicase domain. As suggested by its structure, cumulative evidences documented that ectopic expression of mda-5 leads to growth inhibition and/or apoptosis in various cell lines. However, the signaling pathways involved in mda-5-mediated killing have not been elucidated. In this study, we utilized either genetically modified cloned rat embryo fibroblast cells overexpressing different functionally and structurally distinct oncogenes or human pancreatic and colorectal carcinoma cells containing mutant active ras to resolve the role of the Ras/Raf signaling pathway in mda-5-mediated growth inhibition/apoptosis induction. Rodent and human tumor cells containing constitutively activated Raf/Raf/MEK/ERK pathways were resistant to mda-5-induced killing and this protection was antagonized by intervening in this signal transduction cascade either by directly inhibiting ras activity using an antisense strategy or by targeting ras-downstream factors, such as MEK1/2, with the pharmacological inhibitor PD98059. The present findings provide a further example of potential cross-talk between growth-inhibitory and growth-promoting pathways in which the ultimate balance of these factors defines cellular homeostasis, leading to survival or induction of programmed cell death.

Conditioned place preference associates with the mRNA expression of diazepam binding inhibitor in brain regions of the addicted rat during withdrawal

The diazepam binding inhibitor (DBI) modulating the functions of the GABAA receptors is involved in the maladaptation of neural system during using opiate, but its role in opiate dependence is not fully understood. Using conditioned place preference (CPP) rat model and in situ hybridization technique, we examined the correlation between opiate dependence and the mRNA expression of DBI. We found that chronic morphine treatment enabled CPP and increased the DBI mRNA expression in crucial brain regions of addiction. Withdrawal for 3 days caused significant physical signs and further increased the DBI mRNA expression. Both the DBI mRNA and CPP expression remained significantly high but physical signs were at control level in the animals withdrawal for 6 days. Remarkably, the DBI mRNA expressions in the CA1 region of the hippocampus (CA1), ventral tagmental area (VTA), nucleus accumbens (NAc) and amygdala (AMG) were positively correlated to CPP during the periods from withdrawal for 3 days to withdrawal for 6 days. These findings suggest that DBI may play a role in both physical and psychological dependence of opiates.

Longitudinal surveys of prevalence rates and use patterns of illicit drugs at selected high-prevalence areas in China from 1993 to 2000

AIMS

To identify the prevalence, patterns and trends of illicit drug use in the general population of selected high-prevalence areas in China between 1993 and 2000.

DESIGN, SETTING AND PARTICIPANTS

Cluster sampling was employed and the Epidemiological Inventory for Illicit Drug Use (EIIDU) used as survey instrument. In 1993, 1996 and 2000, 56 792, 67 319 and 53 747 individuals aged 15 or above in community were interviewed, respectively, at the three time-points.

MEASUREMENTS

Demographics and drug-related data were collected and the prevalence patterns of illicit drug are described.

FINDINGS

The life-time prevalences of illicit drug use in the three consecutive surveys in 1993, 1996 and 2000 were 1.08, 1.60 and 1.52%, respectively, and the 1-year prevalence rates were 0.91, 1.17 and 1.17%, respectively. Heroin was the first choice for drug use (51.8% in 1993, 83.4% in 1993 and 95.9% in 2000). The two most frequent routes of drug administration were inhalation (89.2% in 1993, 60.1% in 1996 and 93.5% in 2000) and intravenous injection (27.2% in 1993, 31.0% in 1996 and 25.7% in 2000).

CONCLUSION

At least for the time being, illicit drug use may have plateaued in these selected high-prevalence areas.

Meta-analysis in plant pathology: synthesizing research results

ABSTRACT Meta-analysis is a set of statistical procedures for synthesizing research results from a number of different studies. An estimate of a statistical effect, such as the difference in disease severity for plants with or without a management treatment, is collected from each study along with a measure of the variance of the estimate of the effect. Combining results from different studies will generally result in increased statistical power so that it is easier to detect small effects. Combining results from different studies may also make it possible to compare the size of the effect as a function of other predictor variables such as geographic region or pathogen species. We present a review of the basic methodology for meta-analysis. We also present an example of meta-analysis of the relationship between disease severity and yield loss for foliar wheat diseases, based on data collected from a decade of fungicide and nematicide test results.

Drinking and drinking patterns and health status in the general population of five areas of China

AIMS

To understand drinking patterns, health status related to drinking and the level of unrecorded alcoholic beverage consumption for the general population living in five areas of China in 2001.

METHODS

By cluster sampling, 24992 community residents aged 15 years or older were interviewed by trained psychiatrists using structured questionnaires provided by WHO.

RESULTS

The 1-year drinking rate was 59.0%, and the point prevalence rate of dependence was 3.8%. The average annual consumption of pure alcohol was 4.47 l. The 1-year morbidity from gastritis/ulcer in the whole sample was 7.9%, which associated nonlinearly to alcohol intake, and heart disease and cerebral infarction/cerebral haemorrhage showed V-shaped curve relationships.

CONCLUSIONS

The rate of alcohol use was higher in men than in women, and the annual alcohol consumption per capita was higher than that in the 1990s in the selected areas. Alcohol consumption plays a role in the development of alcohol-related physical diseases.

Operon prediction by comparative genomics: an application to the Synechococcus sp. WH8102 genome

We present a computational method for operon prediction based on a comparative genomics approach. A group of consecutive genes is considered as a candidate operon if both their gene sequences and functions are conserved across several phylogenetically related genomes. In addition, various supporting data for operons are also collected through the application of public domain computer programs, and used in our prediction method. These include the prediction of conserved gene functions, promoter motifs and terminators. An apparent advantage of our approach over other operon prediction methods is that it does not require many experimental data (such as gene expression data and pathway data) as input. This feature makes it applicable to many newly sequenced genomes that do not have extensive experimental information. In order to validate our prediction, we have tested the method on Escherichia coli K12, in which operon structures have been extensively studied, through a comparative analysis against Haemophilus influenzae Rd and Salmonella typhimurium LT2. Our method successfully predicted most of the 237 known operons. After this initial validation, we then applied the method to a newly sequenced and annotated microbial genome, Synechococcus sp. WH8102, through a comparative genome analysis with two other cyanobacterial genomes, Prochlorococcus marinus sp. MED4 and P.marinus sp. MIT9313. Our results are consistent with previously reported results and statistics on operons in the literature.

Association between apolipoprotein CI HpaI polymorphism and sporadic Alzheimer's disease in Chinese

OBJECTIVE

To investigate into the relationship of apolipoprotein CI (ApoCI) polymorphism with sporadic Alzheimer's disease (AD) in Chinese.

SUBJECTS AND METHODS

A total of 257 AD patients and 242 age-matched elderly individuals were genotyped for the ApoCI HpaI and apolipoprotein E (ApoE) HhaI polymorphisms.

RESULTS

The ApoCI A allele was associated with AD of moderate to severe dementia when patients were divided into two subgroups according to Clinical Dementia Rating scale, and the AA genotype was strongly associated with moderate to severe AD in ApoE epsilon4 allele carriers [odds ratio (OR) = 8.19, 95% confidential interval: 1.28-52.30, after adjusting for age and gender by logistic regression analysis], although in total no significant differences of allele or genotype frequency between patients and controls were found.

CONCLUSION

The present study partially confirmed the previous findings, suggesting that the ApoCI A allele might contribute to the susceptibility to moderate to severe sporadic AD in Chinese.

Anti-oxidant effects of estrogen reduce [Ca2+]i during metabolic inhibition

We previously reported that 17beta-estradiol (betaE2) inhibits the rise in [Ca(2+)](i) and [Na(+)](i) during metabolic inhibition (MI) in mouse cardiomyocytes, but the mechanism has not yet been clarified. Estrogen has been reported to have anti-oxidant properties. We, therefore, have investigated whether interaction with the estrogen receptor (ER) is involved, or whether estrogen reduces free-radical-induced impairment of Na(+)-K(+) ATPase in cardiac myocytes, and whether this effect reduces [Ca(2+)](i) rise. Male mouse ventricular myocytes were studied. Flow cytometry was used with fluo-3 for [Ca(2+)](i) measurement. Dead cells were excluded from analysis by propidium iodide fluorescence. betaE2 reduced the increase in [Ca(2+)](i) during MI even in the presence of the ER blocker tamoxifen. A similar effect on [Ca(2+)](i) was produced by its non-estrogenic isomer, betaE2-estradiol. Other hormones (estrone and estriol) with a phenolic structure also inhibited Ca(2+) overload during MI, but testosterone without the structure did not. The betaE2 effect was attenuated by inhibition of Na(+)-Ca(2+) exchanger (KB-R7943) or Na(+)-K(+) ATPase (low K(+) or ouabain), but not by block of L-type Ca(2+) channel (nifedipine). Tiron (4,5-dihydroxy-1,3-benzenedisulfonic acid), a superoxide scavenger, decreased the rise in [Ca(2+)](i) and abolished the betaE2 effect during MI. We conclude that the acute cardioprotective effect of estrogen during MI may be mediated by an ER-independent anti-oxidant action, which results in improved function of Na(+)-K(+) ATPase.