[Characterization of Echinostoma miyagawai in domestic ducks in Wuhu City]

OBJECTIVE

To investigate the morphological characteristics of Echinostoma miyagawai in domestic ducks in Wuhu area, and to explore the feasibility of the cytochrome oxidase subunit-1 (Cox1) gene as a molecular marker for the identification of E. miyagawai.

METHODS

E. miyagawai was isolated from free-ranged domestic ducks in Wuhu area, and the parasites were stained and identified. In addition, the mitochondrial Cox1 gene of E. miyagawai was amplified using a PCR assay, and the amplification product was sequenced and aligned with the GenBank database to yield the homology for the identification of parasite species in combination with morphological findings. Intra-species comparison was done based on the Cox1 gene sequence.

RESULTS

The prevalence of E. miyagawai infection was 16.67% in domestic ducks in Wuhu area, and the adult E. miyagawai was 6.6 to 13.2 mm in length. The size of the E. miyagawai Cox1 gene was approximately 660 bp, which had a 99.68% homology to the E. miyagawai accessed in GenBank. The morphological findings were in agreement with molecular identification.

CONCLUSIONS

E. miyagawai infection is common in domestic ducks in Wuhu area, and the mitochondrial Cox1 gene is a feasible marker of intra- and inter-species molecular identification of Echinostoma.

Comparison and Confirmation of Quantitative Trait Loci Conferring Partial Resistance to Rice Sheath Blight on Chromosome 9

Sheath blight (SB), caused by Rhizoctonia solani, is one of the worst rice (Orzya sativa) diseases worldwide. Resistance to the SB disease in rice is a complex trait controlled by quantitative trait loci (QTLs). Through map integration, we found several previously identified SB resistance (SBR) QTLs reported in inconsistent regions on the long arm of chromosome 9. Five of them were detected on 'Jasmine 85' (J85), 'Minghui 63' (MH63), and 'Lemont' (LMNT) rice and were designated qSB-9^J85-1, qSB-9^J85-2, qSB-9^MH63-1, qSB-9^MH63-2, and qSB-9^LMNT, respectively, in the present study. To further verify and physically map the five potential SBR QTLs, we introduced these SBR QTLs into a common susceptible variety (LMNT) and developed a few chromosomal segment substitution lines through marker-assisted selection. After artificial inoculation with the SB fungus, we were able to validate qSB-9^J85-2 but not the other four SBR QTLs; whereas, on MH63, an SBR QTL designated qSB-9^MH63-3 was confirmed in the region defined by markers Y83 and Y91.8 that included qSB-9^J85-2, covering approximately 1,235 kb. Both qSB-9^J85-2 and qSB-9^MH63-3 appeared to be dominant resistance genes and contributed to similar levels to SB resistance, reducing SB disease severity by approximately 1.0 on a 0-to-9 SB disease rating system. After comparing with another confirmed SBR QTL (qSB-9^TQ) from 'Teqing' rice (TQ), we conclude that qSB-9^J85-2, qSB-9^MH63-3, and qSB-9^TQ are probably controlled by the same allelic resistance genes. These results will accelerate the utilization of this major SBR QTL and its map-based cloning.

Indiscernible benefit of high-resolution HLA typing in improving long-term clinical outcome of unrelated umbilical cord blood transplant

The success of allogeneic hematopoietic stem cell transplantation depends in part on the accuracy of human leukocyte antigen (HLA) matching between the donor-recipient pair. The higher the number of matching HLA alleles, the smaller the chance that the transplant recipient will develop complications. Umbilical cord blood (UCB) transplantation was noted to result in a remarkably low frequency and severity of graft-versus-host disease (GvHD) and graft rejection compared to that in unrelated bone marrow transplant recipients. At present most banks match UCB donors for respective recipients by HLA-A, -B low-resolution typing and -DRB1 high-resolution typing. We retrospectively conducted high-resolution sequence-based HLA typing on DNA samples available from 65 Chinese UCB-recipient pairs typed previously by using low-resolution sequence-specific oligonucleotide probes and sequence-specific primers, and evaluated the clinical outcome. High-resolution typing revealed imperceptible HLA alleles that were hardly identified in low-resolution typing. Univariate analyses demonstrated no significant correlation between the extents of high-resolution HLA disparity with engraftment, graft failure, acute GvHD, transplant-related mortality and long-term 6-year overall survival. Data from the study suggest that high-resolution typing for HLA-A, -B and -DRB1 contributed no substantial improvement to UCB transplant outcome. Low-resolution typing appears to be amenable to matching UCB-recipient pairs without compromising the quality of transplant.

Banking and transplantation of umbilical cord blood in Guangzhou, China

BACKGROUND

Umbilical cord blood (UCB) is an alternative source of hematopoietic stem cells (HSC) for transplantation of patients with hematologic malignancies or hereditary diseases.

METHODS

We developed a provincial UCB bank in Guangzhou, China, using good manufacturing practices and standard operating procedures to address donor eligibility, collection, characterization, processing, storage and release from quarantine. The banking activities were analyzed.

RESULTS

From June 1998 to May 2005, 8623 UCB units of Han ethnic origin were collected; 4147 (48.1%) were stored, while 4476 (51.9%) were discarded as a result of pre-determined exclusion criteria. A median volume of 95.5 mL (range 60-227.7) and 1.2 x 10(9) (0.8-9.3) nucleated cells were collected. The cell viability was 97.8% (90-100%). The CD34+ cell count of 3691 (89.0%) UCB units was 5.2 x 10(6) (0.3-131.6) and clonogenic assays of 4036 (97.3%) UCB units demonstrated 9.8 x 10(5) (0.04-135.8) CFU-GM, 0.3 x 10(5) (0.0-18.6) CFU-GEMM and 8.8 x 10(5) (0.0-74.2) BFU-E. A total of 0.4% (15/3863) UCB derived from babies known to have health problems at age 6 months was discarded. Up to May 2005, 151 units were issued for transplantation to 127 patients [90 (70.9%) children and 37 (29.1%) adults]. The infused nucleated cells in unrelated single-unit recipients were 3.4 x 10(7)/kg (1.7-14.9) for adults (n=19) and 5.7 x 10(7)/kg (2.0-20.5) for children (n=71), respectively. The numbers of days for the engraftment of neutrophils among 65 children and 22 adults were 17 (7-41) and 20 (10-42), respectively.

DISCUSSION

Data of this study show that stringent procedures and comprehensive policies are requisite for pursuing the banking and release of quality UCB for successful transplantation.

Platelet characteristic antigens of CD34+ cells in cryopreserved cord blood: a study of platelet-derived microparticles in transplant processing

BACKGROUND AND OBJECTIVES

In previous studies, we found that platelet microparticles (PMPs) bind to cord blood (CB) CD34+ cells and transfer adhesion molecules to them, which enhances their engraftment. Before applying this phenomenon in actual transplants, we investigated the effect of PMPs on cryopreserved CD34+ cells in CB.

MATERIALS AND METHODS

We cryopreserved 18 CB units, then evaluated the binding of PMPs to CD34+ cells after thawing, by varying the expression of platelet characteristic antigens (CD41a, CD61, CD62P and CXCR4) on these cells. Adherence of the CD34+ cells, coated with freeze/thaw-induced PMPs, to endothelium and fibronectin was also studied, as were the effects of thrombin-induced PMPs from both fresh and preserved CB platelets.

RESULTS

PMPs induced by freezing and thawing adhered less well to CD34+ cells than did those from fresh CB, and cells coated with these PMPs had poor adherence. However, thrombin-induced PMPs from both fresh and preserved CB platelets bound equally well to cryopreserved CD34+ cells and improved their adhesion properties.

CONCLUSIONS

PMPs could be a useful tool for enhancing engraftment after CB transplantation.

[Preliminary study of the gene structure of human glycosylphosphatidylinositol specific phospholipase D]

To explore the cDNA and its genomic gene structure of human glycosylphosphatidylinositol specific phospholipase D (GPI-PLD), the stromal cells from human bone marrow were cultured, and the GPI-PLD cDNA was successfully cloned from stromal cells (GenBank Accession AY007546). After analyzing this cDNA, we found that it codes the signal peptide as well as the mature peptide (817 AA) of GPI-PLD. Compared with the cDNA cloned from human pancreas and liver, the homology of the cDNA is 99% and 95% respectively. After searching GenBank, we aligned the genomic gene of the GPI-PLD by DNATools software, and found that the GPI-PLD genomic gene was located in the human 6p22.1-22.3 and contained 25 exons, TATA box, CAAT box, enhancer and the sequence binding homo domain of Pit-1/GHF-1.

[Protective effects of bepridil in combination with anisodamine on myocardial ischemia and reperfusion injury in rats]

The effects of bepridil (Bep) in combination with anisodamine (Ani) on myocardial ischemia and reperfusion injury induced by ligating the left coronary artery were studied in rats. Administration of a combination of Bep and Ani was found to decrease the incidence of arrhythmia induced by myocardial ischemia and reperfusion, increase the myocardial superoxide dismutase (SOD) activities and reduce the myocardial ultrastructural injury in rats. The effect of combination of Bep and Ani was shown to be better than either Bep or Ani alone.

[Effects of atropine on contraction of rabbit aortic smooth muscle and cell proliferation]

The calcium antagonistic actions of atropine (Atr) and verapamil (Ver) were studied on the contraction of rabbit thoracic aorta strips induced by CaCl2 and KCl. Both Atr and Ver were found to depress the contraction as demonstrated by the shift-to-right of the dose-effect relationship curves and the decrease of maximal responses, with the value of pD'2 being 4.4 and 5.8 respectively. The intracellular Ca(2+)-dependent component of NE-induced aortic strip contraction was also inhibited by the 2 drugs, but the extracellular Ca(2+)-dependent component was barely or not inhibited by Atr before its concentration was raised to 100 mumol/L. These results indicate that the depressive effect of Atr on aortic contraction is mainly exerted by acting on the PDC (potential-dependent channel). The action of Atr on proliferation of cells was also studied in rabbit aortic smooth muscle cell (ASMC) culture. The growth was inhibited by Atr when Ca2+ was present in the medium. When Ca2+ was absent, however, the growth was stimulated by Atr 20.6-185.2 mumol/L, but inhibited by Atr 555.7-1666.7 mumol/L, suggesting that Ca2+ is somehow involved in the action of Atr on ASMC growth.

[Calcium antagonism of anisodamine on isolated rabbit thoracic aorta]

Anisodamine (Ani) or verapamil (Ver) relaxed the contracted thoracic aortic strips induced by CaCl2 and KCl in a noncompetitive manner with pD2' 3.6 and 5.8, respectively. Ani 50 mumol.L-1 and Ver 1 mumol.L-1 inhibited the intracellular Ca(2+)-dependent component of norepinephrine-induced contraction of aorta, but Ani 0.1 mmol.L-1 did not decrease the extracellular Ca(2+)-dependent component. In the presence of Ca2+, Ani 2.3 mumol.L-1 inhibited the proliferation of aortic smooth muscle cells. In the absence of Ca2+, the effect induced by Ani was biphasic-stimulatory at 2.3 mumol.L-1 concentrations and inhibitory at 61.7 mumol.L-1 concentrations. These results suggest that Ani, similar to Ver, mainly inhibits the potentially operated calcium channels.