Association of misconceptions about HIV transmission and discriminatory attitudes in rural China

This study examined HIV-related knowledge and attitudes among 524 randomly selected adult residents from 12 rural Chinese communities where HIV infection among plasma donors has been reported. Most participants were familiar with the main routes of HIV transmission but had substantial misconceptions about risk of HIV transmission through casual social contacts. Higher score of misconception and being older and married independently predicted stronger discriminatory attitude. Intervention programs with focus on eliminating misconceptions about HIV transmission may reduce stigma.

P53 gene codon 72 polymorphism and risk of esophageal squamous cell carcinoma: a case/control study in a Chinese population

The aims of this study were to investigate whether p53 gene codon 72 polymorphism was a biomarker associated with esophageal squamous cell carcinoma (ESCC) and its relationship with smoking status in China. The p53 genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism among 673 patients with ESCC and 694 healthy controls. The association between p53 genotypes and risk of developing ESCC was estimated by odds ratios (OR) and their 95% confidence intervals (CIs) computed by logistic regression. Compared with Arg/Arg homozygotes, Pro/Pro homozygotes had a nearly twofold increased risk (adjusted OR, 1.83; 95% CI, 1.35-2.48). For the Pro/Arg heterozygotes, there was no evident increased risk (adjusted OR, 1.01, 95% CI, 0.78-1.30). Furthermore, the risk associated with the Pro/Pro variant genotype was more pronounced in younger patients at diagnosis (= 45 years) (OR, 7.4; 95% CI, 1.44-37.89, P = 0.02), in women (OR, 3.15; 95% CI, 1.52-4.53, P = 0.02) and in non-smokers (OR, 2.49; 95% CI, 1.58-3.94) and light smokers (OR, 2.13; 95% CI, 1.15-3.93). But tests for homogeneity between smoking-related OR showed no significant differences (P = 0.4). The p53 gene codon 72 Pro/Pro genotype was significantly associated with the increased risk of ESCC in a Chinese mainland population and may be an independent factor in susceptibility to ESCC. The association was especially noteworthy in women and in younger patients.

The UL31 to UL35 gene sequences of Duck enteritis virus correspond to their homologs in herpes simplex virus 1

Five ORFs in the genome of Duck enteritis virus (DEV) corresponding to UL31, UL32, UL33, UL34, and UL35 genes of Herpes simplex virus 1 (HSV-1) were amplified by a modified "targeted gene walking" PCR, cloned, and sequenced. UL33, UL34, and UL35 genes were oriented from the left to the right of genome, while UL31 and UL32 had an opposite orientation. A comparison of deduced amino acid sequences of the DEV ORFs with their alphaherpesvirus homologs showed well-conserved regions except for the UL34 and UL35 genes. Phylogenetic analysis revealed that DEV was closer to the genus Mardivirus than to any other genus of the subfamily Alphaherpesvirinae. Based on this evidence, we proposed to assign DEV to the subfamily Alphaherpesvirinae.

Evaluation of thermal properties of food materials at high pressures using a dual-needle line-heat-source method

Thermal properties of food systems at high pressure (HP) are important in the design and operation of HP processing equipment. Available techniques for thermal property evaluation under HP conditions are still very limited. In this study, a dual-needle line-heat-source (DNL) device was installed in an HP vessel to evaluate thermal conductivity (k), diffusivity (alpha), and volumetric heat capacity (C(pV)) of foods at high pressure. The DNL probe was calibrated using glycerin (0.1 MPa) and 2% (w/w) agar gel (0.1 to 350 MPa) at 5 and 25 degrees C. Calibration results showed a good correlation with the reference data of pure water: R(2)= 0.966 for thermal conductivity and R(2)= 0.837 for diffusivity, and a small standard deviation of relative error (3.18%) for the volumetric heat capacity. Fresh potato and cheddar cheese were used as test samples at 5 degrees C at selected pressure levels (0.1 to 350 MPa). The potato samples gave thermal properties very close to those of pure water, but much higher than those of the cheese. The k and alpha values of both potato and cheese increased with pressure and a 2nd-order polynomial well fitted their pressure dependency. The volumetric heat capacity data did not show a clear pressure-dependency trend. The experimental system worked well for the evaluation of thermal properties at pressures up to 350 MPa.

Soil organic carbon decomposition and carbon pools in temperate and sub-tropical forests in China

Decomposition of soil organic carbon (SOC) is a critical component of the global carbon cycle, and accurate estimates of SOC decomposition are important for forest carbon modeling and ultimately for decision making relative to carbon sequestration and mitigation of global climate change. We determined the major pools of SOC in four sites representing major forest types in China: temperate forests at Changbai Mountain (CBM) and Qilian Mountain (QLM), and sub-tropical forests at Yujiang (YJ) and Liping (LP) counties. A 90-day laboratory incubation was conducted to measure CO(2) evolution from forest soils from each site, and data from the incubation study were fitted to a three-pool first-order model that separated mineralizable soil organic carbon into active (C(a)), slow (C(s)) and resistant (C(r)) carbon pools. Results indicate that: (1) the rate of SOC decomposition in the sub-tropical zone was faster than that in the temperature zone, (2) The C(a) pool comprised approximately 1-3% of SOC with an average mean residence time (MRT) of 219 days. The C(s) pool comprised approximately 25-65% with an average MRT of 78 yr. The C(r) pool accounted for approximately 35-80% of SOC, (3) The YJ site in the sub-tropical zone had the greatest C(a) pool and the lowest MRT, while the QLM in the temperature zone had the greatest MRT for both the C(a) and C(s) pools. The results suggest a higher capacity for long-term C sequestration as SOC in temperature forests than in sub-tropical forests.

Tests of soil organic carbon density modeled by InTEC in China's forest ecosystems

The integrated terrestrial ecosystem C-budget model (InTEC) developed by Chen and co-workers has been used successfully to predict carbon dynamics of forests in Canada. It was tested here for forest soil organic carbon (SOC) density of China's northern temperate zone and southern subtropical zone. The results show that the simulated SOC density is highly correlated and in broad agreement with observations in Liping and in Changbaishan, representing the southern subtropical zone and the northern temperate zone in China, respectively. SOC density ranged from 2.2 to 11.2 kg/m(2) in Liping and from 3.4 to 14.8 kg/m(2) in Changbaishan. The correlation coefficients (r(2)) are 0.63 (N=16) and 0.76 (N=14) between the simulated and measured data in Liping and Changbaishan, respectively. The SOC densities under different vegetation types in Liping decrease in the order of mixed forest, broadleaf forest, Chinese fir, couch grass, and Chinese redpine, and in Changbaishan in the order of mixed forest, silver fir, larch forest, and birch forest.

Expression of serotonin transporters by peripheral blood mononuclear cells of rhesus monkeys (Macaca mulatta)

It has been well established that serotonin (5-hydroxytryptamine, 5-HT) plays a key role in neuro-endocrine-immune networks, mostly through its receptors and/or transporters. Although the presence of 5-HT receptor mRNAs in peripheral blood mononuclear cells (PBMCs) of rhesus monkeys has been reported, there is little information about serotonin transporter (SERT) expression by these cells. To examine SERT expression at the transcription and translation level, one-step RT-PCR, confocal microscopy and flow cytometry were used to detect SERT mRNA and protein expression by rhesus monkey PBMCs. It was found that SERT mRNA could be detected by RT-PCR from all of the rhesus macaque PBMC RNA samples and the nucleotide sequence of the amplicons was identical to the published SERT mRNA sequence. Low level SERT immunoreactivity was also demonstrated on the surface of rhesus PBMCs by confocal microscopy. Almost all lymphocytes and most monocytes were positive for SERT by flow cytometry. In the 2 rhesus macaques examined by multicolor flow cytometry, SERT(bright) cells were more than 84%, 94%, and 96% among CD20+, CD3+, and CD3+CD4+ lymphocytes respectively. These data demonstrate expression of SERT by rhesus macaque PBMCs, and indicate that rhesus macaques would be suitable models to test the in vivo immune regulatory effects of 5-HT or drugs targeting SERT.

Imiquimod: A TLR-7 agonist as adjuvant for a recombinant protein cancer vaccine

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Purpose: This clinical trial evaluates the safety and adjuvant activity of imiquimod, a toll-like receptor (TLR)-7 agonist, when given with a NY-ESO-1 protein vaccine. Imiquimod, by locally activating and recruiting dendritic cells (DCs) into the skin, is expected to stimulate antigen uptake by DCs, induce maturation and migration to draining lymph nodes, and to induce antigen-specific T and B cell immunity. Methods: Pilot study; 9 patients with resected stage 2B-3C malignant melanoma. Four 21 day cycles consisted of topical imiquimod cream (250 mg) on days 1–5 and id. injected NY-ESO-1 protein (100 mcg) into the site on day 3. Blood was drawn at several time points for immune monitoring; skin punch biopsies were obtained from control, imiquimod and vaccination sites 48 hours after the last vaccination. Results: The regimen was tolerated well, all patients completed four vaccinations. AEs were mild and transient and included injection site reactions (8/9 patients), fatigue (4/9 patients) and fever (2/9 patients). Significant levels of antigen-specific CD4+ or CD8+ T cell responses were not detected in ex-vivo ELISPOT assays. However, intracellular cytokine staining assays after in vitro pre-stimulation indicated that 6 of 8 subjects developed NY-ESO-1 CD4+ T cell responses. Humoral immunity was manifest by the induction of anti-NY-ESO-1 antibodies in 7/9 patients post-vaccination. Histochemistry of skin sections showed significant dermal mononuclear cell infiltrates in Imiquimod treated skin, whereas none were seen in untreated skin (p<0.01). IHC revealed markedly increased numbers of CD3+ (T-cells), CD68+ (macrophages/monocytes), CD123+ (plasmacytoid DCs) and DC-LAMP+ (mature myeloid DCs) immune cells in Imiquimod treated skin when compared with control skin of the same patients (p<0.05). Conclusion: Imiquimod, a topical immune response modifier, generated clear inflammatory infiltrates in the dermis, with significant increases in antigen-presenting cells and T cells. Imiquimod was well tolerated when used as an adjuvant to an NY-ESO-1 protein vaccine. Systemic immunity of both humoral and cellular types was induced in the majority of patients; however, responses were weak and the vaccine combination needs to be optimized in future studies.

No significant financial relationships to disclose.

Analysis of HIV-1 CRF07_BC gag p6 sequences indicating novel deletions in the central region of p6

We amplified gag sequences from 66 individuals infected with HIV-1 CRF07_BC during 2003-2005 in the Xinjiang region of China. A novel deletion of 7aa (including a KELY motif) in the central region of the CRF07_BC gag p6 domain was detected, which has not been reported in other HIV-1 subtypes. Further deletions of up to 13aa (including KQE and KELY motifs) was also found in this domain, representing the biggest natural deletion up to now. Moreover, the CD4+ count and viral load level indicated that 1-13aa deletions in CRF07_BC gag p6 do not have a significant effect on viral replication and fitness.

Renal histopathology of stone-forming patients with distal renal tubular acidosis

To define the renal tissue changes in stone-forming patients with distal renal tubular acidosis (dRTA), we performed intra-operative papillary and cortical biopsies in five patients. The main abnormalities were plugging of inner medullary collecting ducts (IMCD) and Bellini ducts (BD) with deposits of calcium phosphate in the form of apatite; epithelial cell injury and loss was marked. Plugged ducts were surrounded by interstitial fibrosis, but the fibrosis was generalized, as well, and was a main feature of the histopathology even when plugging was not present. In contrast, common idiopathic calcium oxalate stone formers (SF) never manifest intra-tubule crystals or interstitial fibrosis. Patients with brushite (calcium monohydrogen phosphate) stones and those with cystine stones have many fewer IMCD and BD plugged with apatite (or cystine, in cystinuria), and interstitial fibrosis is limited to the regions around plugged ducts. Patients with dRTA often present a radiographic picture of nephrocalcinosis. Our direct surgical observations reveal that these may be surgically removable stones, especially in patients with well preserved renal function. In all, dRTA SF have a more diffuse papillary renal disease than other SF thus studied, and are also unusual for the degree of interstitial fibrosis.

Localization and activity of calmodulin is involved in cell–cell adhesion of tumor cells and endothelial cells in response to hypoxic stress

Adhesion of tumor cells to endothelial cells is known to be involved in the hematogenous metastasis of cancer, which is regulated by hypoxia. Hypoxia is able to induce a significant increase in free intracellular Ca2+ levels in both tumor cells and endothelial cells. Here, we investigate the regulatory effects of calmodulin (CaM), an intracellular calcium mediator, on tumor cell-endothelial cell adhesion under hypoxic conditions. Hypoxia facilitates HeLa cell-ECV304 endothelial cell adhesion, and results in actin cytoskeleton rearrangement in both endothelial cells and tumor cells. Suppression of CaM activation by CaM inhibitor W-7 disrupts actin cytoskeleton organization and CaM distribution in the cell-cell contact region, and thus inhibits cell-cell adhesion. CaM inhibitor also downregulates hypoxia-induced HIF-1-dependent gene expression. These results suggest that the Ca2+ -CaM signaling pathway might be involved in tumor cell-endothelial cell adhesion, and that co-localization of CaM and actin at cell-cell contact regions might be essential for this process under hypoxic stress.

A prospective, blinded analysis of thymidylate synthase and p53 expression as prognostic markers in the adjuvant treatment of colorectal cancer

BACKGROUND

Despite previous studies, uncertainty has persisted about the role of thymidylate synthase (TS) and p53 status as markers of prognosis in colorectal cancer (CRC).

PATIENTS AND METHODS

A total of 967 patients accrued to a large adjuvant trial in CRC were included in a prospectively planned molecular substudy, and of them, 59% had rectal cancer and about 90% received adjuvant chemotherapy (either systemically or randomly allocated to intraportal 5-fluorouracil infusion or both). TS and p53 status were determined, blinded to any clinical data, by immunohistochemistry using a validated polyclonal antibody or the DO-7 clone, respectively, and their relationships with overall survival were examined.

RESULTS

High TS expression was observed in 58% and overexpression of p53 in 60% of tumours. TS expression correlated with tumour stage, and p53 overexpression, with rectal cancers. There was no evidence that either marker was significantly associated with survival by either univariate (TS hazard ratio (HR) = 0.94, 95% CI 0.76-1.18 and P = 0.6 and p53 HR = 0.98, 95% CI 0.78-1.23 and P = 0.9) or multivariate analyses (TS HR = 0.99, 95% CI 0.79-1.25 and P = 0.9 and p53 HR = 0.98, 95% CI 0.78-1.23 and P = 0.8).

CONCLUSIONS

Neither TS nor p53 expression has significant prognostic value in the adjuvant setting of CRC.

Renal crystal deposits and histopathology in patients with cystine stones

We have biopsied the papillae of patients who have cystine stones asking if this stone type is associated with specific tissue changes. We studied seven cystine stone formers (SF) treated with percutaneous nephrolithotomy using digital video imaging of renal papillae for mapping and obtained papillary biopsies. Biopsies were analyzed by routine light and electron microscopy, infrared spectroscopy, electron diffraction, and micro-CT. Many ducts of Bellini (BD) had an enlarged ostium, and all such were plugged with cystine crystals, and had injured or absent lining cells with a surrounding interstitium that was inflamed to fibrotic. Crystal plugs often projected into the urinary space. Many inner medullary collecting ducts (IMCD) were dilated with or without crystal plugging. Apatite crystals were identified in the lumens of loops of Henle and IMCD. Abundance of interstitial Randall's plaque was equivalent in amount to that of non-SF. In the cortex, glomerular obsolescence and interstitial fibrosis exceeded normal. Cystine crystallizes in BD with the probable result of cell injury, interstitial reaction, nephron obstruction, and with the potential of inducing cortical change and loss of IMCD tubular fluid pH regulation, resulting in apatite formation. The pattern of IMCD dilation, and loss of medullary structures is most compatible with such obstruction, either from BD lumen plugs or urinary tract obstruction from stones themselves.

An autosomal genomic screen for dementia in an extended Amish family

Apolipoprotein E (APOE) is the only universally confirmed susceptibility gene for late-onset Alzheimer disease (LOAD), although many loci are believed to modulate LOAD risk. The genetic homogeneity of isolated populations, such as the Amish, potentially provide increased power to identify LOAD susceptibility genes. Population homogeneity in these special populations may reduce the total number of susceptibility genes contributing to the complex disorder, thereby increasing the ability to identify any one susceptibility gene. Dementia in the Amish is clinically indistinguishable from LOAD in the general population. Previous studies in the Amish demonstrated a significantly decreased frequency of the APOE-4 susceptibility allele, but significant familial clustering of dementia [M.A. Pericak-Vance, C.C. Johnson, J.B. Rimmler, A.M. Saunders, L.C. Robinson, E.G. D'Hondt, C.E. Jackson, J.L. Haines, Alzheimer's disease and apolipoprotein E-4 allele in an Amish population, Ann. Neurol. 39 (1996) 700-704]. These data suggested that a genetic etiology independent of APOE may underlie the dementia observed in this population. In the present analysis, we focused on a large, multiplex, inbred Amish family (24 sampled individuals; 10 of whom are affected). We completed a genomic screen to identify novel LOAD loci (n=316 genetic markers), using both model-dependent "affecteds-only" analysis (dominant and recessive) and model-independent affected relative pair analysis. Interesting results (lod>1.5 or p<0.01) were obtained for markers on eight chromosomes (2q, 5q, 6q, 7p, 8p, 8q, 11p, 18p, 18q, and 19q). The highest overall score was a multipoint lod score of 3.1 on chromosome 11p. Most regions we identified were not previously detected by genomic screens of outbred populations and may represent population-specific susceptibilities to LOAD. These loci are currently under further investigation in a study of LOAD including additional Amish families.