[Role and related mechanism of resolvin D1 in lung ischemia reperfusion injury in rats]

Objective: To investigate the role and related mechanism of resolvin D1 (RvD1) in lung ischemia-reperfusion injury (LIRI) in rats. Methods: Forty male Sprague-Dawley rats, 7-8 weeks, weighing 220-280 g, were divided into 4 groups using a random number table method: sham operation group, lung ischemia reperfusion control group, normal saline group, and RvD1 group. The rat model of LIRI was produced by 45 min of occlusion of the left hilum of lungs followed by 150 min reperfusion. In sham group, no blocking of the left hilum of lung after thoracotomy; Normal saline 2 ml/kg and RvD1 100 μg/kg were injected respectively at 10 min of reperfusion in normal saline group and RvD1 group. Blood samples were collected from the femoral vein for determination of interleukin (IL)-6, tumor necrosis factor (TNF)-α, soluble inter-cell adhesion molecules (sICAM-1) concentrations at 150 min of reperfusion. The rats were sacrificed after collection of blood samples and then lung tissues were taken for observation of the pathological changes and for measurement of lung wet/dry weight ratio (W/D). The the contents of malondialdehyde (MDA), monocyte chemoattractant protein (MCP)-1, macrophage inflammatory protein (MIP)-2 and the activity of myeloperoxidase (MPO) in lung tissues were determined. The protein relative expression of nuclear factor (NF)-κB in lung tissues was detected by Western blot. Lung tissue cell apoptosis was detected with TUNEL method. Results: The plasma level of IL-6, TNF-α, sICAM-1 in normal saline group and RvD1 group were significantly higher than those in the Sham group [(110±7), (100±4) vs (72±3) ng/L, (151±8), (153±6) vs (104±5) ng/L, (2 690±133), (2 760±167) vs (1 953±125) ng/L]. Besides, NF-κB protein relative expression level of lung tissues up-regulated [(0.681±0.033), (0.664±0.024) vs (0.292±0.011)] (all P<0.05). The W/D, apoptosis index, MDA, MCP-1, MIP-2 contents and MPO activity in lung ischemia reperfusion control group, normal saline group and RvD1 group were significantly higher than those in the Sham group [(5.92±0.31), (5.85±0.24), (5.06±0.08) vs (4.14±0.10), (32.9±1.5)%, (31.9±1.3)%, (17.7±1.8)% vs (8.1±0.6)%, (72.1±2.3), (66.7±3.7), (34.0±1.4) vs (22.0±0.8) nmol/mg, (3.99±0.28), (3.86±0.25), (2.66±0.16) vs (1.47±0.17) pg/mg, (9.45±0.53), (9.68±0.62), (7.62±0.22) vs (4.70±0.41) pg/mg, (3.01±0.18), (2.92±0.19), (1.58±0.11) vs (0.98±0.07) U/g] (all P<0.05). The plasma levels of the cytokines mentioned above, the W/D, the apoptosis index, MDA, MCP-1, MIP-2 contents and MPO activity in RvD1 group were significantly lower than those in the lung ischemia reperfusion control group [(63±4) vs (110±7) ng/L, (90±8) vs (151±8) ng/L, (1 835±182) vs (2 690±133) ng/L, (5.06±0.08) vs (5.92±0.31), (17.7±1.8)% vs (32.9±1.5)%, (34.0±1.4) vs (72.1±2.3) nmol/mg, (2.66±0.16) vs (3.99±0.28) pg/mg, (7.62±0.22) vs (9.45±0.53) pg/mg, (1.58±0.11) vs (3.01±0.18) U/g]. Besides, NF-κB protein relative expression level of lung tissues down-regulated [(0.313±0.012) vs (0.681±0.033)] (all P<0.05). Inflammatory cell infiltration in LIRI groups increased significantly, while it was significantly reduced in RvD1 group. Conclusion: RvD1 can effectively alleviate the tissue damage caused by lung ischemia-reperfusion through down-regulating NF-κB expression, relieving inflammatory reaction and oxidative stress, reducing apoptosis in rats.

Correlation between the development of calcium oxalate stones and polymorphisms in the fibronectin gene in the Uighur population of the Xinjiang region of China

Here, we have investigated the correlation between calcium oxalate stone formation and Fn gene polymorphisms in urinary calculi patients among the Uighur population (Xinjiang region). In this case control study, genomic DNA extracted from the peripheral blood of 129 patients with calcium oxalate stones (patient group) and 94 normal people (control group) was used to genotype polymorphisms in the rs6725958, rs10202709, and rs35343655 sites of the Fn gene by polymerase chain reaction-restriction fragment length polymorphism. Subsequently, the association between different genotypes and susceptibility to calcium oxalate stone formation was compared among the patient and control groups. Single nucleotide polymorphisms (SNPs) were detected in the rs6725958, rs10202709, and rs35343655 sites of the Fn gene among the patient and control groups. The genotype distributions of the three loci complied with the Hardy-Weinberg equilibrium. The results of allele frequencies of the patient/control group for polymorphisms in the rs6725958 site of the Fn gene were C = 179 (69.92%)/119 (63.30%) and A = 77 (30.08%)/69 (36.70%), in the rs10202709 site were C = 245 (95.70%)/176 (93.63%) and T = 11 (4.30%)/12 (6.38%), and in the rs35343655 site of the Fn gene were A = 139 (54.30%)/87 (46.28%) and G = 117 (45.70%)/101 (53.72%). We observed no significant differences between the three SNPs and development of calcium oxalate stones. Polymorphisms in rs6725958, rs10202709, and rs35343655 of the Fn gene had no obvious effect on the susceptibility to the development of calcium oxalate stones in the Uighur population, residing in the Xinjiang region of China.

Genetic diversity and evolution of two capsid protein genes of citrus tristeza virus isolates from China

The genetic diversity and population structure of citrus tristeza virus (CTV) isolates from China were investigated based on partial sequences spanning the C-terminal end of p61 and the complete sequences of the CPm and CP genes. Phylogenetic analysis revealed five known groups (RB, T30, T36, HA and VT) and one new group (VI) consisting of only Chinese CTV isolates. Incongruent phylogenetic trees coupled with recombination analysis suggested several recombination events in the CPm gene. Positive selection was detected at codon 9 of CPm and codons 31, 41 and 68 of CP. The widespread CTV subpopulation AT-1 found in China has a unique amino acid insertion at the C-terminus of p61, which could increase CTV population complexity with implications for the evolutionary history of the virus. Our results suggest relevant roles for gene flow, purifying selection and recombination in shaping the CTV population in China.

The epitope structure of Citrus tristeza virus coat protein mapped by recombinant proteins and monoclonal antibodies

It has been known that there exists serological differentiation among Citrus tristeza virus (CTV) isolates. The present study reports three linear epitopes (aa 48-63, 97-104, and 114-125) identified by using bacterially expressed truncated coat proteins and ten monoclonal antibodies against the native virions of CTV-S4. Site-directed mutagenesis analysis demonstrated that the mutation D98G within the newly identified epitope (97)DDDSTGIT(104) abolished its reaction to MAbs 1, 4, and 10, and the presence of G98 in HB1-CP also resulted in its failure to recognize the three MAbs. Our results suggest that the conformational differences in the epitope I (48)LGTQQNAALNRDLFLT(63) between the CPs of isolates S4 and HB1 might contribute to the different reactions of two isolates to MAbs 5 and 6. This study provides new information for the antigenic structures of CTV, and will extend the understanding of the processes required for antibody binding and aid the development of epitope-based diagnostic tools.

[Distributional characteristics of nutrients in the sea-surface microlayer and subsurface water of the Bohai and Yellow Sea in summer]

The horizontal distributional characteristics of nutrients (DIN, PO4(3-) -P, SiO3(2-) -Si) were studied in the sea-surface microlayer (SML) and subsurface water of the Bohai and Yellow Sea in June 2011, and the vertical distributions of nutrients in the transects of the Yellow Sea Cold Water Mass and the north of the Changjiang River estuary were also investigated. The results showed that the nutrient concentrations in the sea-surface microlayer and subsurface water decreased gradually from inshore to offshore, and higher values were observed in the Changjiang River estuary. A tongue-shaped distribution was observed in the south of the Yellow Sea as a result of the Changjiang diluted water. Stratification occurred in the surface layer and vertical mixing characteristics were observed in the bottom due to the influence of the Yellow Sea Cold Water Mass. In the vertical distributions, higher concentrations of DIN and SiO3(2-) -Si in the north of the Changjiang River estuary occurred in the sea surface compared with the bottom due to the Changjiang River diluted water. The enrichment results of NH(+) -N, NO2(-) -N, NO3(-)-N, PO4(3-) -P, SiO3(2-)-Si and DIN showed that the sea-surface microlayer displayed an apparent enrichment for nutrients except NO3(-) -N, and the mean enrichment factors ranged from 1.37 to 2.21.

The genotypes of citrus tristeza virus isolates from China revealed by sequence analysis of multiple molecular markers

The genotypes of ten citrus tristeza virus (CTV) isolates from central China were determined by examining multiple molecular markers (MMMs) using 11 primer pairs. The results revealed that one isolate contained a single T30 genotype, two isolates contained a single VT genotype, and the other seven isolates were mixtures of two or more genotypes. Sequence analysis of amplified MMMs showed a high genetic diversity in Chinese CTV populations. The genotypes resembling T36, RB and B165 were identified from Chinese CTV isolates for the first time. Our results suggest that genotype assignment of CTV cannot be based solely on the amplification profiles of MMMs, and sequencing of MMMs is required.

Effective pressure and bubble generation in a microfluidic T-junction

To improve the existing trial-and-error process in designing a microfluidic T-junction, a systematic study of the geometrical (mainly the channel length) effects on the generated bubbly/slug flow was conducted to figure out basic design guidelines based on experimental and theoretical analyses. A driving system with dual constant pressure sources, instead of the commonly used dual constant volume-rate sources (such as two syringe pumps), was chosen in this study. The newly proposed effective pressure ratio (P(e)*) has revealed its advantages in excluding the surface tension effect of fluids. All the data of generated bubbly/slug flow for a given geometry collapse excellently into the same relationship of void fraction and effective pressure ratio. This relationship is insensitive to the liquid viscosity and the operation range is strongly affected by the geometrical effect, i.e., the channel length ratio of downstream to total equivalent length of the main channel in a T-junction chip. As to the theoretical design and analysis of gas-liquid-flow characteristics in a microfluidic T-junction, which is still sporadic in the literature, the proposed semi-empirical model has successfully predicted the operation boundaries and the output flow rate of bubbly/slug flow of different investigated cases and demonstrated its usability.

Five-year results of a randomized, single-center study of tacrolimus vs microemulsion cyclosporine in heart transplant patients

BACKGROUND

Previous multicenter, randomized trials, lacking standardized post-transplant protocols, have compared tacrolimus (Tac) and cyclosporine (CyA, Sandimmune) and demonstrated similar outcomes with some different adverse effects. The microemulsion form of CyA (mCyA, Neoral) has replaced Sandimmune CyA as the more widely utilized CyA formulation. This is the first 5-year follow-up study of a large, single-center trial (n = 67) under a standardized post-transplant protocol comparing Tac and mCyA.

METHODS

Sixty-seven heart transplant patients were randomized to Tac (n = 33) or mCyA (n = 34), both in combination with corticosteroids and azathioprine without cytolytic induction. Five-year end-points included survival, Grade > or = 3A or treated rejection, angiographic cardiac allograft vasculopathy (CAV; any lesion > or = 30% stenosis), renal dysfunction (creatinine > or = 2.0 mg/dl), use of two or more anti-hypertensive medications, percent diabetic and lipid levels.

RESULTS

Five-year survival, freedom from Grade > or = 3A or any treated rejection and angiographic CAV, mean cholesterol level and percent diabetic were similar between the two groups. The Tac group had a significantly lower 5-year mean triglyceride level (Tac 97 +/- 34 vs mCyA 175 +/- 103 mg/dl, p = 0.011) and average serum creatinine level (Tac 1.2 +/- 0.5 mg/dl vs mCyA 1.5 +/- 0.4 mg/dl, p = 0.044). There was a trend toward fewer patients requiring two or more anti-hypertensive drugs in the Tac group (Tac 33% vs mCyA 59%, p = 0.065).

CONCLUSIONS

Tac and mCyA appear to be comparable with regard to 5-year survival, freedom from rejection and CAV. However, compared with mCyA, Tac appears to reduce the adverse effect profile for hypertriglyceridemia and renal dysfunction and the need for hypertensive medications.

Reference typing report for complement receptor 1 (CR1)

A total of 100 Chinese blood donors (50 from Shen-Zhen and 50 from Taiwan) were studied by the participants in addition to 9 reference samples. A new nomenclature for the CR1 structural alleles was recommended by the participants which would use a numbering system, e.g. CR1*1. The structural allele frequencies in the Chinese were: CR1*1 (190 kD) 0.96, CR1*2 (220 kD) 0.03, CR1*3 (160 kD) 0.01 and CR1*4 (250 kD) 0.00. The HindIII expression polymorphism was also studied and the high expressing allele had a gene frequency of 0.71 while the low expressor gene frequency was 0.28. Erythrocyte copy numbers were quantified and compared between laboratories with good correlation (R = 0.55-0.88). The mean (+/- SD) erythrocyte copy number was 463 (+/- 229) in the Taiwan donors and 446 (+/- 207) in the Mainland Chinese.

Fate of DNA targeted to hepatocytes by asialoglycoprotein polylysine conjugates

The data indicate that partial hepatectomy results in a decrease in degradation of targeted DNA. This appears to be due to an inhibition of the endocytotic pathway shortly after hepatectomy and is associated with the accumulation of targeted DNA within a population of light endosomal vesicles. It is likely that these vesicles serve as a reservoir from which targeted DNA gradually escapes and can be found in the nucleus. The DNA targeted to liver is capable of expressing the marker gene, and the DNA in the vesicles is transfection competent, suggesting that a substantial portion is intact. Overall, the receptor-mediated delivery system is highly efficient in transporting foreign DNA to liver cells. Partial hepatectomy and the ensuing cellular events provide a means of inhibiting the degradative portion of the endocytotic pathway. Pharmacological agents that can mimic the cellular processes that occur after partial hepatectomy may be useful in increasing the duration of foreign gene expression without the trauma of surgery.