Smooth muscle cell phenotypic diversity between dissected and unaffected thoracic aortic media

AIM

Smooth muscle cell (SMC) phenotypic switching in the aortic media may play a critical role in the pathogenesis of thoracic aortic dissection (TAD). However, few investigations are available and most of the observations are based on histological examinations without in vitro evidence. This study, which was performed both in vivo and in vitro, was designed to investigate SMC phenotypic diversity between dissected and unaffected aortic media.

METHODS

Using optimized explant technique, aortic medial SMCs were obtained from patients with TAD and controls. In vivo and in vitro expression of α-smooth muscle actin (α-SMA), smooth muscle-myosin heavy chain 2 (SM-MHC-2), smooth muscle-calponin (SM-Calponin), Vimentin, osteopontin (OPN) and non-muscle myosin heavy chain B (SMemb) were evaluated by immunostaining and immunoblotting. SMC proliferation was also analyzed.

RESULTS

Although the majority of SMCs from the dissected media displayed an elongated, spindle- or triangle-like shape as control SMCs, there were some oval or flat, quadrate cells in the dissection cultures. In contrast with controls, SMCs derived from the dissected media uniformly showed the negative staining for the contractile proteins and the intense staining for the synthetic markers. Similarly, in vitro protein levels of α-SMA, SM-MHC-2, SM-Calponin and Vimentin were significantly decreased to 60.1% (P<0.05), 12.0% (P<0.01), 23.1% (P<0.01) and 32.5% (P<0.01) respectively, whereas those of OPN and SMemb were markedly elevated by5.7- and 10.3-fold respectively (P<0.01 for both). In vivo expression of the phenotypic markers showed the parallel results. Furthermore, SMCs derived from the dissected media exhibited the enhanced proliferation (P<0.05).

CONCLUSION

We have established a simple and potent method to acquire SMCs from the dissected and unaffected aortic media. Compared to the contractile SMCs in the unaffected media, those in the dissected media manifest phenotypic switching from the contractile to the synthetic type. The primary cultures can be subsequently used as in vitro models and contribute to further elucidating the etiopathogenesis of TAD.

Vascularized osteomyocutaneous allografts are permissive to tolerance by induction-based immunomodulatory therapy

Vascularized composite allografts (VCAs) are unique among transplanted organs in that they are composed of multiple tissues with disparate antigenic and immunologic properties. As the predominant indications for VCAs are non-life-threatening conditions, there is an immediate need to develop tolerance induction strategies and to elucidate the mechanisms of VCA rejection and tolerance using VCA-specific animal models. In this study, we explore the effects of in vitro induced donor antigen-specific CD4(-) CD8(-) double negative (DN) Treg-based therapy, in a fully MHC mismatched mouse VCA such as a vascularized osteomyocutaneous as compared to a non-VCA such as a full thickness skin (FTS) transplantation model to elucidate the unique features of VCA rejection and tolerance. We demonstrate that combined therapy with antigen-induced CD4 derived DN Tregs and a short course of anti-lymphocyte serum, rapamycin and IL-2/Fc fusion protein results in donor-specific tolerance to VCA, but not FTS allografts. Macrochimerism was detected in VCA but not FTS allograft recipients up to >60 days after transplantation. Moreover, a significant increase of CD4(+) Foxp3(+) Tregs was found in the peripheral blood of tolerant VCA recipients. These data suggest that VCA are permissive to tolerance induced by DN Treg-based induction therapy.

Nested clade phylogeographical analysis of the finless porpoise (Neophocaena phocaenoides) inhabiting Chinese and Japanese coasts

The finless porpoise (Neophocaena phocaenoides) is a small cetacean whose survival is largely affected by human activity. The characteristics and structures of 3 populations in China and 4 to 5 populations in Japan have been well documented, although their history and origins remain poorly understood. In this study, nested clade phylogeographical analysis was applied to mtDNA sequences from finless porpoises to delineate the historical factors shaping the divergence pattern of this species. The sampling range covered most habitats of the finless porpoise, including the Chinese and Japanese coasts and the Yangtze River. A nested cladogram was constructed, and all 3 (2-step) clades were linked together without interior or tip status. Our data indicated that haplotype C was the most common among most individuals and populations, which could be the most ancient haplotype among all of the sampled types. As populations expanded to reside in different areas, ancient types with haplotype C mutated to other haplotypes, which were kept endemic by geological barriers that changed during glacial cycles that retarded gene flow. Populations in Japanese Pacific coasts and inland sea and post-arc marginal seacoasts and the Yangtze River were formed by the residual individuals left when allopatric fragmentation occurred in the ancestral population. The existence of highly endemic haplotypes and high genetic diversity from the Ariake Sound, Tachibana Bay, and the Yellow Sea indicated a relatively isolated state in these areas during the evolutionary history of the finless porpoise. The phylogenetic pattern revealed in the present study provided a better understanding of the biogeographical events that affected the finless porpoise within this region.

Factors associated with acceptability of circumcision among male drug users in western China: a cross-sectional study

This study is aimed to investigate whether male circumcision (MC) is feasible among IDUs in China. 1304 drug users who attended methadone maintenance therapy clinics in Guangxi, Chongqing and Xinjiang were selected for participation by using convenience sampling, and completed a self-administered questionnaire. The factors associated with the acceptability of MC were examined via multiple logistic regression models. 45.2% (589/1304) of the participants reported an acceptance of MC. Many of the participants who were initially not willing to accept MC (715/1304) had changed their mind when they were informed that MC would reduce the risk of HIV and STDs (43.4%; 310/715), that MC is associated with few surgery-related complications (23.1%; 165/715), that the surgical procedure could be arranged free of charge (20.1%, 144/715). In the multivariate analysis, higher acceptability of MC was associated with knowledge of the hazards of phimosis (OR=2.22), the presence of phimosis (OR=14.87), and knowledge that MC can prevent AIDS and STDs (OR=1.49); while lower acceptability was associated with residing in Chongqing province (OR=0.41) and an educational level of junior (OR=0.64) and senior high (OR=0.63) school. The MC policy targeting IDUs in China should take into account these factors associated with MC acceptability.

High prevalence of vitamin D insufficiency in pregnant women working indoors and residing in Guiyang, China

BACKGROUND/AIM

To assess the status of 25-hydroxyvitamin D [25(OH)D] in pregnant women in their second and third trimesters, who reside and work indoors in Guiyang, China.

SUBJECTS AND METHODS

A total of 311 pregnant women in their 12th to 40th gestational week were engaged in employment located indoors in the urban area of Guiyang and completed a questionnaire on living habits. Levels of serum 25(OH)D were measured from fasting venous blood by liquid chromatography-mass spectrometry (LC-MS/MS). Levels of 25(OH)D were classified as vitamin D deficient [25(OH)D<20 ng/ml], insufficient [20 ng/ml≤25(OH)D<30 ng/ml], or sufficient [25(OH)D≥30 ng/ml].

RESULTS

The mean serum level of 25(OH)D was 14.69±6.81 ng/ml. Vitamin D deficiency, insufficiency and sufficiency were found in 260 (83.6%), 39 (12.5%), and 12 (3.9%) women, respectively. The mean level of 25(OH)D in the third trimester was significantly higher than in the second trimester (p<0.001). The mean 25(OH)D level in summer (June, July, August) was significantly higher than in the other seasons (p<0.001). The 25(OH)D level in pregnant women compliant with pre-natal calcium or multivitamin supplements was higher than in those not taking supplements (p<0.001).

CONCLUSIONS

These results suggest that pregnant women residing in Guiyang urban area and working indoors are at high risk of vitamin D insufficiency, particularly during spring, winter, and autumn, regardless of use of pre-natal calcium and multivitamins. Appropriate vitamin D supplementation is necessary to improve maternal vitamin D nutrition.

Artificially engineered superlattices of pnictide superconductors

Significant progress has been achieved in fabricating high-quality bulk and thin-film iron-based superconductors. In particular, artificial layered pnictide superlattices offer the possibility of tailoring the superconducting properties and understanding the mechanism of the superconductivity itself. For high-field applications, large critical current densities (J(c)) and irreversibility fields (H(irr)) are indispensable along all crystal directions. On the other hand, the development of superconducting devices such as tunnel junctions requires multilayered heterostructures. Here we show that artificially engineered undoped Ba-122/Co-doped Ba-122 compositionally modulated superlattices produce ab-aligned nanoparticle arrays. These layer and self-assemble along c-axis-aligned defects, and combine to produce very large J(c) and H(irr) enhancements over a wide angular range. We also demonstrate a structurally modulated SrTiO3(STO)/Co-doped Ba-122 superlattice with sharp interfaces. Success in superlattice fabrication involving pnictides will aid the progress of heterostructured systems exhibiting new interfacial phenomena and device applications.

Attenuated expression of gelsolin in association with induction of aquaporin-1 and nitric oxide synthase in dysfunctional hearts of aging mice exposed to endotoxin

Sepsis triggered by endotoxinemia may impair cardiac function. A decline in tolerance to septic shock occurs with aging. This study addressed the hypothesis that aging negatively impairs expression of gelsolin, and axerts the regulatory effects on the water channel protein aquaporin-1 (AQP-1) and endotoxin-inducible nitric oxide synthase (iNOS). We explored whether the age-related gene changes are associated with the cardiac dysfunction induced by endotoxic stress exposure. Male mice at young (3-month) and old (12-month) ages received intraperitoneal injections of saline or lipopolysaccharide (LPS, 30mg/Kg). Cardiac performance and morphology were analyzed by echocardiography at baseline and 2 and 24 h after injection. At the end of treatment, the animals were sacrificed, and cardiac tissues were collected for assessing expression of gelsolin, AQP-1, iNOS, and transcription-3 (STAT3). LPS administration led to a decreased contractility while increasing cardiac dimensions in both young and old mice. LPS also markedly induced expression of gelsolin in both animal groups. However, compared to young mice, old mice showed compromised induction of gelsolin and cardiac performance in response to endotoxin. Meanwhile, the LPS-exposed old animals exhibited higher levels of AQP-1, iNOS, and phosphorylated STAT3. Gelsolin-null mice had increased expression of glycosylated AQP-1 and STAT3 phosphorylation as well as cardiac dysfunction. Thus, endotoxin administration induces expression of gelsolin, AQP-1 and pro-inflammatory genes, such as iNOS. Our data suggest that changed expression of gelsolin, AQP-1 and iNOS may contribute to dysfunction of hearts in aged subjects with septic endotoxinemia.

Role of mitogen-activated protein kinase cascades in 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced apoptosis in neuronal pheochromocytoma cells

Mitogen-activated protein kinases (MAPKs) are involved in neuronal death caused by many cytotoxins. Conventional MAPKs consist of three family members: extracellular signal-regulated kinase-1/2 (ERK1/2), c-Jun N-terminal kinase (JNK) and p38. It has been originally shown that ERK1/2 is important for cell survival, whereas JNK and p38 are deemed stress responsive and thus involved in apoptosis. However, information describing the role of MAPKs in 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced neurotoxicity is insufficient. The aim of this study was to identify the role of MAPK cascades in TCDD-induced neurotoxicity using differentiated pheochromocytoma (PC12) cells as a model for neuronal cells. Cell viability assay, terminal deoxynucleotidyl transferase dUTP nick-end labeling assay and flow cytometry analysis showed that TCDD attenuated cell viability with a dose- and time-dependent manner and significantly induced apoptosis in primary cortical neurons and PC12 cells. Western blot analysis indicated that TCDD markedly activated the expression of ERK1/2, JNK and p38 in TCDD-treated PC12 cells. Furthermore, PD98059 (ERK1/2 inhibitor), SP600125 (JNK inhibitor) and SB202190 (p38 inhibitor) notably blocked the effect of TCDD on cell apoptosis. Based on the findings above, it is concluded that the activation of MAPK signaling pathways may be associated with TCDD-mediated neuronal apoptosis.

Synthesis of Dodecyl Lauroyl Benzene Sulfonate and its Application in Enhanced Oil Recovery

A new hydrophobic surfactant, dodecyl lauroyl benzene sulfonate (DLBS), was synthesized and its application in enhanced oil recovery by alkali-surfactant-polymer (ASP) flooding was studied. The results show that DLBS can be synthesized by reaction of industrial dodecyl benzene with lauroyl chloride in the presence of AlCl3, followed by sulfonation with ClSO3H and neutralization with NaOH. The lauroyl-group is confirmed to be connected to the para-position of the alkylbenzene by 1HNMR spectrum. The synthesized DLBS is well soluble in pure water and reservoir (connate) water at 45°C. It is highly surface active which is indicated by its low CMC of 1.1 · 10−5 mol/L, and its low surface tension, γcmc of 28.6 mN m−1. By mixing with heavy alkylbenzene sulfonates of relatively low average molar mass (387 g mol−1) at a total surfactant concentration of 5 mM, DLBS can reduce the interfacial tension of Daqing crude oil/connate water to an order of 10−3 mN/m at 45°C in the presence of 0.5–1.0 wt.% NaOH and 1000 mg L−1 of polymer. If the NaOH was replaced by a gentle alkaline salt, Na2CO3, certain amounts of dodecyl dimethyl carboxy betaine were added and the concentration of Na2CO3 was increased to 1.2–2.0 wt.%, the interfacial tension of Daqing crude oil/connate water can also be reduced to an ultralow value. Therefore DLBS is a good hydrophobic surfactant applicable in ASP flooding with either NaOH or Na2CO3 as alkaline agents.

Pollen wall development: the associated enzymes and metabolic pathways

Pollen grains are surrounded by a sculpted wall, which protects male gametophytes from various environmental stresses and microbial attacks, and also facilitates pollination. Pollen wall development requires lipid and polysaccharide metabolism, and some key genes and proteins that participate in these processes have recently been identified. Here, we summarise the genes and describe their functions during pollen wall development via several metabolic pathways. A working model involving substances and catalytic enzyme reactions that occur during pollen development is also presented. This model provides information on the complete process of pollen wall development with respect to metabolic pathways.

A direct comparison of expression profiles of adhesion molecules on naïve T cells between cord blood and steady-state bone marrow grafts of healthy donors

INTRODUCTION

We compared the profiles of adhesion molecule expression on naïve T cells between umbilical cord blood (UCB) and steady-state bone marrow (SS-BM) grafts.

METHODS

The expressions of 4 adhesion molecules, including very late antigen 4 (VLA-4), intercellular adhesion molecule-1 (ICAM-1), L-selectin, and lymophocyte function-associated antigen-1 (LFA-1) on naïve T cells in UCB (n = 25) and SS-BM (n = 10) were analyzed using flow cytometry.

RESULTS

The expressions of ICAM-1 and L-selectin on CD4(+) T cells and CD8(+) T cells in UCB were significantly lower than those on SS-BM (P < .05 for all). The expressions of VLA-4 and LFA-1 on CD8(+) T cells in UCB were significantly lower than those of SS-BM (P = .002 and .047, respectively). Compared with SS-BM, we observed lower expression of ICAM-1 on naïve CD4(+) and CD8(+) T cells in UCB (P < .001 for all). The percentages of interferon (IFN)-γ positive cells among naïve CD4(+) and CD8(+) T-cell subsets were significantly lower in UCB, leading to ready polarization of naïve UCB T cells from a Th1 to Th2 phenotype versus those on SS-BM.

CONCLUSIONS

Our results among UCB suggested lower intensities of ICAM-1 expression on naïve T cells and their easier polarization from Th1 to Th2 elements.

Degree of Chinese ancestry affects behavioral characteristics of infant rhesus macaques (Macaca mulatta)

BACKGROUND

The use of Chinese-origin macaques in biomedical research is problematic for some scientists because of the reported behavioral and physiological differences from those of Indian origin. However, few studies have examined the effects of varying degrees of Chinese ancestry (DCA) on behavior, and they were typically based on small sample sizes and unusual rearing conditions.

METHODS

Using data from a colony-wide program, we examined whether DCA was related to behavior and temperament ratings reflecting emotionality (fearfulness, aggression, and anxiety) and activity. The 249 subjects, born and reared in an outdoor social environment, were separated from their groups for a 25-h period of indoor testing. Their DCA (range: 0.6-99.4%) was determined by analyzing the frequency of short tandem repeat alleles.

RESULTS AND CONCLUSIONS

The major effect of DCA was on fearfulness, with the more hybridized animals scoring lowest and the more pure Indian- and Chinese-origin macaques resembling each other.

Gene expression patterns of invertase gene families and modulation of the inhibitor gene in tomato sucrose metabolism

Patterns of gene expression in the different types of sucrose metabolism in the tomato are highly variable and heritable. This genetic variation causes considerable functional differences. We examined the patterns of expression of invertase (Inv) gene families and an invertase inhibitor (INH) gene involved in elongating roots, hypocotyls, and fruit of the tomato (Lycopersicon esculentum cv. Micro-Tom and L. chmielewskii) through a real-time quantitative PCR analysis. We found that the Lin6 gene plays an important role in the vegetative growth stage. Lin5 and Lin7 did not express in Micro-Tom, but did express in L. chmielewskii. Overall relative expression levels of sucrose Inv gene families were significantly lower in L. chmielewskii during the reproductive growth stage than in Micro-Tom, being up to hundreds of times lower. It was not expressed in the dissepiment in L. chmielewskii. We suggest that differences in sucrose accumulation in tomato fruit is mainly due to differentially expressed invertase gene families at the later fruit growth stages.

Association of HLA-DRB1 single nucleotide polymorphisms with left ventricular remodelling in elderly patients with essential hypertension

OBJECTIVE

To investigate the associations between human leucocyte antigen DRβ1 (HLA-DRB1) gene polymorphisms and cardiovascular remodelling (left ventricular dilatation [LVD]) in Han Chinese patients ≥ 60 years old, with essential hypertension.

METHODS

LVD was diagnosed via echocardiographic measurements. Multiplex polymerase chain reaction-ligase detection reaction was used to determine the genotypes of three HLA-DRB1 single nucleotide polymorphisms (SNPs; rs2308765, rs9269186 and rs3135388).

RESULTS

HLADRB1 rs2308765 wild-type (G) allele and genotype (GG) were associated with decreased risk of LVD. HLA-DRB1 rs9269186 and rs3135388 were not associated with LVD risk. Mean waist and abdominal circumferences were significantly larger in patients with, compared with those without, LVD. Multivariate logistic regression analyses found that rs2308765 was associated with LVD (GT + TT versus GG; odds ratio 7.958; 95% confidence interval 1.935, 32.723).

CONCLUSIONS

Mutation in HLA-DRB1 rs2308765 was associated with increased risk of LVD in elderly patients with hypertension. Genotype analysis may allow identification of patients at high risk of cardiovascular events such LVD.