Objective Network emulation system constructs a virtual network environment which has the characteristics of controllable and repeatable network conditions. This makes it possible to predict the availability and performance of new protocols and algorithms before deploying to Internet. Methods PARNEM, a parallel discrete event network emulation system described in this paper has the following characteristics: ① BREEN - a BSP based real-time event scheduling engine; ② application transparent flexible interactive mechanism; ③ legacy network model reuse. Conclusion PARNEM allows detailed and accurate study of application behavior. Comprehensive case studies covering bottleneck bandwidth measurement and distributed cooperative web caching system demonstrate that network emulation technology opens a wide range of new opportunities for examining the behavior of applications.

Objective To explore the possible immune pathophysiology of CD4+T regulatory(CD4+Treg)in acquired aplastic anemia(AA).Methods The levels of CD4+CD25+Treg、CD4+CTLA-4+Treg、CD4+PD-1+Treg、CD3+CD8-IL-10+Treg、CD3+CD8-TGF-?1+Treg、CD3+CD8-IL-4+ Treg in the bone marrow of 23 cases of AA at active phase,10 cases of AA at recovery phase and 15 normal controls were measured,and the relationship between CD4+Treg and priming immune factor-CD28 or effective immune factor-IFN-? was also evaluated respectively.Results Contrast to normal controls,while CD4+CTLA-4+Treg of AA at active phase decreased markedly,levels of other CD4+Treg:CD4+CD25+Treg,CD4+PD-1+Treg,CD3+CD8-IL-10+Treg,CD3+CD8-TGF-?1+Treg and CD3+CD8-IL-4+Treg did not change significantly.Contrast to normal controls,the ratio of membrane costimulatory of CD28/CTLA-4 and CD28/PD-1 were all increases significantly in AA at active phase;the ratio of cytokines in cell plasma of IFN-?/IL-4,IFN-?/TGF-?,and IFN-?/IL-10 were also increased significantly.Conclusion In AA,not only at priming stage but also at effective stage,the positive costimulatory increased while the negative regulatory costimulatory decreases or dose not change,which shifted the immune balance to intensification.That the CD4+Treg does not expand to control the intensified immune reaction might be one of immunopathgenesis of AA.

Objective To investigate the effect of KIR-HLA receptor-ligand model on the unrelated allo-hematopoietic stem cell transplantation (Allo-HSCT) of acute lymphoblastic leukemia (ALL). Methods The KIR genotype of 23 pairs of ALL patients and their HLA-matched unrelated donors obtained from the Database of China Marrow Donor Program. KIR genotype was determined using PCR-SSP. The expression of inhibitory KIR(iKIR) was determined by flow cytometry analysis on recipients after HSCT. Results Among all 23 donor/recipient pairs, 17 donors with KIR2DL2/L3 could find corresponding HLA-Cw1, 3, 7, 8, 12, 14 ligands in their recipients. Six donors with KIR2DL1 could match with HLA-Cw6, 15 in recipients. Sixteen donors with KIR3DL1 could recognize HLA-Bw4 and 12 donors with 3DL2 could find HLA-AI1 in their corresponding recipients, respectively. Ninteen patients were successfully transplanted, and the death rate of transplantation were 33.3% (2/6)and 40.0% (2/5) in KIR receptor-ligand matched model and the graft versus leukemia(HVG) KIR ligand-mismatching pattern. The frequency of acute graft versus host disease(GVHD) was 50.0% and death rate was 12.5% (1/8) in GVH KIR ligand-mismatching. The incidence rate of activated GVHD(aGVHD) was 20.0% in the HVG KIR ligand-mismatching. Five donor/recipient pairs of KIR gene typing were the KIR-haplotype A, 2 donor/recipient pairs with KIR2DS4 * 001/002 were died, 3 donor/recipient pairs with KIR2DS4 * 003-007 were obtained the disease free survival. The expression of CD158a/2DL1 was low when the patient had no aGVHD, but became much higher when aGVHD occurred. The percentage of NK cell of the patients was decreasing since transplantation, but still higher than normal after HSCT[ (23.4 ± 3.8 ) % vs (2.04 ± 0.58) %, P < 0.05 ]. Conclusion Analysis on KIR-HLA gene loci pattern may provide a useful parameter in predicting the clinical outcome of HLA-matched unrelated allogeneic hematopoietic stem cell transplantation for leukemia patients. Moreover, it may help to increase overall survival and disease free survival after HSCT by preventing the development of GVHD.

Objective To evaluate the feasibility and effectiveness of four closure techniques ,large incision with plastic distal at‐tachment and clip with suction ,1 .1 cm small incision with plastic distal attachment and clip with suction in natural orifice translu‐minal endoscopic surgery(NOTES) .Methods Forty‐one ex vivo porcine stomachs were involved in this research .According to the size of incision and different methods of incision closure ,all ex vivo porcine stomachs were divided into four groups .Group A in‐volved 8 ex vivo porcine stomachs ,their size of incision were 1 .2-2 .0 cm ,and their incisions were closured by a clip closure direct‐ly ;group B involved 10 ex vivo porcine stomachs ,their size of incision were 1 .2-2 .0 cm ,and their incisions were closed by plastic end attachment with suction and clip enclosure technique;group C involved 10 ex vivo porcine stomachs ,their size of incision were smaller than 1 .1 cm ,and their incisions were by a clip closure directly ;group D involved 13 ex vivo porcine stomachs ,their size of incision were smaller than 1 .1 cm ,and closured by plastic end attachment with suction and clip enclosure technique .Stomach leaks were evaluated by leaking studies after the procedure .Results In group A ,1 incision was closed successfully ,7 incisions were clo‐sured unsuccessfully ;in group B ,2 incisions were closed successfully ,8 incisions were closed unsuccessfully ;in group C ,2 incisions were closed successfully ,8 incisions were closured unsuccessfully ;in group D ,11 incisions were closed successfully ,2 incisions were Closured unsuccessfully .Fisher′s exact test showed that group D was significantly related to the success of incision closure .The were significant differences between group A and D ,group B and group D(P<0 .05) .Conclusion Small incision(smaller than 1 cm) and plastic end attachment with suction and clip enclosure technique are optimal in NOTES procedure in this ex vivo porcine stomachs study .

Objective To explore the efficacy of non-T cell depletion haploidentical hematopoietic stem-cell transplantation for T lymphoblastic lymphoma (T-LL). Methods 3 T-LL patients achieving complete remission received haploidentical bone marrow stem cell transplantation with granulocyte-colony-stimulating factor (G-CSF) mobilized bone marrow grafts from related donor without T-cell depletion. Two of them received a myeloablative conditioning regimen consisting of high-doses of cyclophosphamide and cytarabine with total body irradiation, whereas the other was preconditioned with busulfan, cyclophosphamide and cytarabine. All patients received strengthened phophylaxis regimen including rabbit anti-thymocyte globulin against acute graft-versus-host disease. Results All patients had rapid hematopoietic engraftment with the median time for neutrophil and platelet recovery being 12 days and 13 days, respectively. They are still alive without relapse at a median follow-up of 24 months (range: 9-75 months). Conclusion Treatment related toxicity can be acceptable in non-T cell depletion haploidenfical hematopoietic stem-cell transplantation for T-LL and the patients may achieve long term survival.

Objective The optimal access for natural orifice transluminal endoscopic surgery is still uncertain .This study was designed to compare the practicability and maneuverability of transgastric ,transunmbilical ,and transrectal approach in abdominal surgery in a canine model .Methods Three dogs were used in this research .Three approach :trangastric ,transunmbilical and tran-srectal approach were carried out for abdominal exploration ,liver biopsy ,bladder biopsy and an attempted cholecystectomy .The ma-neuverability ,endoscopic image ,performer′s perception ,and spatial orientation were evaluated .Results The maneuverability of trangastric ,and transrectal approach NOTES were better than transunmbilical NOTES .Abdominal exploration ,live biopsy ,and bladder biopsy were completed successfully .The cholecystectomy was failed because of poor exposure and difficulty of separating the around tissure .Conclusion The optimal approach for upper abdomen NOTES is transrectal route .For lower abdomen NOTES , the trangastric approach is superior to other accesses .Further study is needed to develop more flexible and precise equipment for NOTES and to evaluate more feasible access approach .

Objective To explore the influence of the killer cell immunoglobulin like receptor (KIR) gene polymorphism on cytomegalovirus (CMV) infection and pathogenesis after hematopoietic stem cell transplantation (HSCT).Methods The KIR genotype was determined by sequence-specific primer polymerase chain reaction (PCR-SSP) in 138 pairs of donors and recipients before HSCT during October,2005 and May,2011.Posttransplant monitoring for CMVpp65 antigen was performed by indirect immune histochemically assays since week 2 after transplantation.The differences between CMV positive group and negative group,inhibitive and active KIR of donors and recipients,and KIR haplotype frequency of donors and recipients were analyzed.Results There were no significant differences in frequency of KIR gene and haplotype AA,AB,BB between the donors and recipients.The frequencies of 2DS2 and 2DS4 * 003-007 of donors in CMV positive group were obviously lower than those in CMV negative group with significant differences(8％ vs 16％,P =0.0420;3％ vs 13％,P =0.0050).There was no significant difference in KIR gene between CMV positive group and CMV negative group.The CMV infection rates of haplotype AA,BB,AB donors were 64.38％,36.84％ and 50.00％,while CMV infection rates of haplotype AA,BB,AB recipients were 53.73％,46.15％ and 51.72％,respectively.The CMV infection rate was higher in the patients received KIR haplotype AA donor than in those received KIR haplotype BB donor (36.84％ vs 64.38％,P =0.0299).2DS4 * 003-007 and haplotype BB of donor were found associated with CMV infection in multifactor analysis.Conclusion KIR genotypes of donors are associated with CMV infection after HSCT.

Humans ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; United States

OBJECTIVETo clarify the clinical, cytogenetical and molecular characteristics and prognosis of Ph(+) ALL patients with ABL kinase domain mutations (ABL-KDMs), and to evaluate the therapeutic value of allogeneic hematopoietic stem cell transplantation (allo-HSCT) combined with tyrosine kinase inhibitor (TKI) in these patients.

METHODSRetrospective analysis of clinical features, molecular genetic characteristics, mutation distribution and prognosis of newly diagnosed Ph(+) ALL patients with ABL-KDMs from February 2010 to August 2014 were performed, and the efficacy of treatment regimen of allo-HSCT combined with different TKIs was compared.

RESULTSOf 88 Ph(+) ALL patients during maintenance treatment stage for ABL-KDMs monitoring, mutation was detected in 42 patients with median time of 8 months from diagnosis to mutation occurrence. The median age of mutation group was 40-year-old, older than that of non-mutation group (32.5-year-old) (P=0.023). The incidence of complex chromosome abnormality of mutation group was higher than that of non-mutation group (P=0.043), with alternations in chromosome 7, 5 and +Ph more frequently observed. There were 21 types of mutation at 18 locations detected, with T315I mutation ranking the top followed by E255K/V, Y253H/F and E459K. Mutation group featured no significant difference in complete remission (CR) rate in contrast to nonmutation group, but was remarkably lower in major molecular remission (MMR) rate than non-mutation group. The 2 year and 5 year overall survival rate of mutation group was 45.4% and 35.0% respectively, much shorter than that of non-mutation group (67.8% and 63.3%), (P=0.047). The median survival of patients with T315I and E255K/V was 19 and 10 months, significantly shorter than that of patients with other mutations. Among the 42 patients with mutations, 14 underwent allo-HSCT, and the median survival was 29 months, longer than that of patients received chemotherapy alone (17 months) (P=0.024). Fourteen allo-HSCT patients were given nilotinib or dasatinib at the time of mutation occurrence, and there was no significant difference in the overall survival in contrast to patients who continue to take imatinib.

CONCLUSIONSABL kinase domain mutations are closely related to the older age and high genomic instability in the newly diagnosed Ph(+) ALL patients. Mutation types showed diversity and complexity, which remarkably affected patients' prognosis and survival. T315I and E255K mutations account for more than half of all cases, characterized by a less favorable prognosis. Currently, allo-HSCT is the only method that has the potential of elongating life expectancy, but the utility of second-generation TKI during relapse does not necessarily have an edge on survival over imatinib.

Chromosome Aberrations ; Dasatinib ; therapeutic use ; Hematopoietic Stem Cell Transplantation ; Humans ; Imatinib Mesylate ; therapeutic use ; Mutation ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; drug therapy ; genetics ; Prognosis ; Protein Kinase Inhibitors ; therapeutic use ; Proto-Oncogene Proteins c-abl ; genetics ; Pyrimidines ; therapeutic use ; Remission Induction ; Retrospective Studies ; Survival Rate

OBJECTIVETo investigate the role of different immunoglobulin- like receptor (KIR)haplotypes in haplo- identical hematopoietic stem cell transplantation (HSCT).

METHODKiller cell KIR genotyping was performed on 468 individuals from 156 unrelated families by PCR-SSP. A total of 624 KIR haplotypes from the parents were used for haplotype analysis. Ninety-two patients received haplo-identical HSCT from one of the parents.

RESULTSThe family study showed segregation of one A haplotype and at least 20 unique B haplotypes. The frequency of haplotype A was 72.92% (455/624). The most commonly observed haplotypes in group B were B1, B2, and B3, present at a frequency of 10.26%, 5.77%, and 4.48%, respectively. Compared to KIR gene matched donors (n=17), grafts from KIR gene mismatched donors (n= 14) had a positive effect on survival after haplo- identical HSCT for AML/MDS patients (OS: 88.2%vs 42.9%,P=0.015; RFS: 88.2%vs 35.7%,P=0.007). No effect was observed for ALL/NHL patients (OS: 76.0%vs 75.0%,P=0.727; RFS: 68.0%vs 65.0%,P=0.866). A significantly lower survival rate was observed for transplants from AA (n=52) and AB1/AB2 donors (n=15), compared to other group Bx donors (n=25) (OS: 53.3%vs 96.0%,P=0.017; RFS: 53.3%vs 92.0%,P=0.019). Meanwhile, the risk of relapse was much higher in AA group (n=52) compared to Bx group (n=40) (25.0%vs 5.0%,P=0.009). A higher risk of TRM was observed in AB1/AB2 group (P=0.012). In addition, transplant from donors carried Cen-B was associated with an increased survival compared with Cen-A homozygous donors (OS: 94.7%vs 68.5%,P=0.036; RFS: 89.5%vs 64.4%,P=0.045).

CONCLUSIONOverall, KIR genotyping and haplotype analyses should be useful for selection of the most optimal donors with favorable KIR gene grafts. KIR gene mismatch donors should be preferred for AML/MDS patients. Selecting donors carried Cen- B and avoiding the selection of donors of KIR genotype AA/AB1/AB2 was strongly advisable for haplo-identical HSCT.

Chronic Disease ; Genotype ; Haplotypes ; Hematopoietic Stem Cell Transplantation ; Humans ; Killer Cells, Natural ; Leukemia, Myeloid, Acute ; therapy ; Neoplasm Recurrence, Local ; Receptors, KIR ; genetics ; Survival Rate ; Tissue Donors