AIM:To synthesize a safe , efficient and targeted nanoparticulate carrier for siRNA delivery to pan-creatic cancer cells .METHODS: Iron oxide nanocrystal with carboxylic acid group-polyethyleneimine ( IONP-PEI ) was synthesized and investigated as a nonviral carrier of siRNA to the pancreatic cells .The size, surface and charge using zeta potential were characterized .The perfect charge ratio between amino groups of IONP-PEI and phosphate groups of siRNA ( N/P) was determined by the transfection efficiency detection , gel retardation assay and MTS assay .An antibody-directed nonviral vector , scFvCD44v6-IONP-PEI nanoparticle attaching to the cancer-associated CD44v6 single-chain variable frag-ment, was constructed as a cancer-targeting nanocarrier for siRNA delivery .Prussian blue staining and immunofluorescent staining were performed to detect the distribution of scFv CD44v6-IONP-PEI/siRNA complexes in the cells .The transfection efficiency , fluorescence intensity and the expression of KRAS at mRNA and protein levels in the cells transfected by IONP -PEI/siRNA and scFv CD44v6-IONP-PEI/siRNA were detected by flow cytometry , fluorescence microscopy , real-time PCR and Western blotting, respectively.RESULTS:The mass ratio of IONP to PEI was 0.75.The suitable ratio of N/P was 20. The averaged size and surface zeta potential of IONP-PEI/siRNA in deionized water were (51.3 ±2.2)nm (diameter) and (21.73 ±8.07)mV, respectively.Red fluorescence was seen in both targeting and nontargeting groups , which clearly re-vealed the intracellular distribution of siRNA and delivery agents .Transfection efficiencies in targeting and nontargeting groups were (89.75 ±1.81)%and (59.87 ±4.52)%, respectively.Down-regulation of the KRAS mRNA in Panc-1 cells transfected with siKRAS by scFvCD44v6-IONP-PEI and IONP-PEI was up to (34.02 ±6.15)%and (51.09 ±6.70)%, re-spectively .The protein level of KRAS was lower in targeting group than that in nontargeting group .CONCLUSION:scFvCD44v6-IONP-PEI is a safe and efficient nanoparticulate carrier for gene delivery .It is more effective to transfer siRNA into the cells and mediate gene silencing effect in vitro than the nontargeting group .

Objective To evaluate the characteristics of abdominal aorta wall motion in different stages of rats atherosclerosis with velocity vector imaging (VVI) technique. Methods Twenty-four healthy SD rats were on high-fat feeding after one week ordinary diet. Abdominal aortic intima-media thickness (IMT), end-systolic blood vessel diameter (Ds), peak systolic velocity (Vs), resistance index (RI), pulsatility index (PI) were measured before and at the end of 8th and 12nd week. Artery wall peak velocity (V_(max)), maximum tangential strain (S_(max)) and the maximum tangential strain rate (SR_(max)) were caculated with VVI. Results Abdominal aortic intima was rough and a small amount of foam cells were found under the light microscope at the end of 8 weeks of high-fat feeding. The values of Smax and SRmax measured at the end of 8th week of high-fat feeding decreased significantly than those of before high-fat feeding (P<0.05). At the end of 12nd week, abdominal aortic intimal was thicker and atherosclerotic plaque appeared somewhere. There were significant differences in artery IMT, Ds, Vs, RI, PI between before and the end of 2nd week of high-fat feeding (P<0.05);the values of V_(max), S_(max), SR_(max) decreased significantly than those of before and at the end of 8th week of high-fat feeding (P<0.05). Conclusion VVI can quantitatively evaluate the vessel wall elasticity in different stage of arteriosclerosis rats.

AIM:To establish an effective and rapid method to develop transplanted subcutaneous pancreatic carcinoma by inducing PANC-1 cells into nude mice, and then use this mouse model to evaluate the tumor-homing and gene-silencing effects of siRNA-loading nanoparticles in vivo.METHODS:Different numbers of PANC-1 cells in 100 μL or 300 μL PBS were inoculated subcutaneously into the right flank of BALB /c (nu/nu) mice.When the tumor volume reached 100 mm 3 , siRNACY 5.5 nanoparticles were injected through the mouse tail vein to perform in vivo imaging assay.Be-sides, the mice were randomly divided into 3 treatment groups treated with PBS, scrambled control RNA nanoparticles and siKras nanoparticles, respectively.The protein expression of Kras was detected by Western blotting and immunohistochemi-cal staining.RESULTS:After inoculated with 1 ×10 7 PANC-1 cells in 300 μL PBS, all mice developed tumors within 2 weeks.The in vivo results showed that siRNA-loading nanoparticles accumulated in the tumor tissues and exerted gene si-lencing effect.CONCLUSION:In the present study, an effective and rapid method was established for PANC-1 cells to induce transplanted subcutaneous pancreatic carcinoma in nude mice within 2 weeks, which is suitable for in vivo imaging and treatment evaluations as a reproducible and reliable way for the further experiments .

OBJECTIVETo investigate the risk factors on initial surgery in Crohn's disease.

METHODSThe clinical data of 173 patients with Crohn's disease who were treated during 2010 and 2014 years in the Second Affiliated Hospital of Sun Yat-Sen University, were analyzed retrospectively. The patients who had received intestinal resection or whose initial symptoms occurred at least 5 years at the end of the follow-up were recruited. Montreal classification was used to evaluate lesion location and disease behavior. The risk factors of the initial surgery were analyzed by using Logistic regression model.

RESULTSEighty-five patients (49.1%) received intestinal resection in 5 years after the onset of symptoms. The result of univariate analysis showed that the probability of surgical treatment is high in patients who were male and those older than 40 years at diagnosis (P<0.05). Lesions involving upper digestive tract, stenosis and penetrating lesions were also the risk factors on initial surgery in Crohn's disease (P<0.05). The result of multivariate analysis showed the relative risk of initial surgery was increased in male gender (OR=2.02, 95%CI:1.04-3.92) and in those who were older than 40 years at diagnosis (OR=2.34,95%CI:1.05-5.22). However, in patients with Crohn's disease involving colon alone, the relative risk of initial surgery was decreased (OR=0.35, 95%CI:0.13-0.97).

CONCLUSIONAbdominal pain is the most common clinical presentation in Crohn's disease. Disease behavior and operation is closely related. Older than 40 years at diagnosis and male gender is high risk factor for surgery while colonic lesion alone is protective factor.

Abdominal Pain ; Colon ; Constriction, Pathologic ; Crohn Disease ; Follow-Up Studies ; Humans ; Logistic Models ; Male ; Protective Factors ; Retrospective Studies ; Risk Factors

Objective:To investigate the variation of T, B, NK lymphocyte subgroup in children with anti-N-methyl-D-aspartate receptor(NMDAR)encephalitis and their clinical significance.Methods:This was a prospective and control study.Forty children primarily diagnosed with anti-NMDAR encephalitis in the department of neurology in Guangzhou Women and Children′s Medical Center from January 2017 to August 2019 served as patient group, 20 healthy children served as control group.Absolute counts and percentages of T, B and NK lymphocytes in whole blood were detected before and 1 month after treatment in patient group.Serum immunoglobulin G(IgG), IgA and IgM were measured before treatment.The blood levels of T, B, NK lymphocyte subgroup were detected with flow cytometer.NMDAR antibody titers of serum and cerebrospinal fluid were detected in patient group.The differences between patient group at different time points and control group were compared.The patients were divided into two groups according to the response to treatment after 2 weeks and the absolute counts of T, B and NK lymphocytes before treatment were compared between groups.Results:Compared with control group, the blood absolute count of B lymphocyte in patient group were significantly higher before and after treatment( P<0.05). There was no significant difference of B lymphocyte in patient group between before and after treatment.After treatment, T cells(including T inhibitory cells and T helper cells)were significantly increased compared with those before treatment and those in control group( P<0.05), but there was no significant difference between patient group and control group before treatment.These with poor response to treatment after 2 weeks had higher level of B, T lymphocyte subgroup compared to those with good response( P<0.05). The level of IgG, IgA, IgM in patient group showed no significant difference with control group.There was no significant correlation between B lymphocyte count in blood and NMDAR antibody titer in cerebrospinal fluid( r=0.282, P>0.05). Conclusion:B lymphocytes increase greatly in children with anti-NMDAR encephalitis, and the level of B lymphocyte subgroup before treatment are associated with treatment response, and T lymphocytes increase greatly after treatment.There is no significant correlation between the titer of NMDAR antibody in cerebrospinal fluid and B lymphocyte level.

OBJECTIVE: To provide a basis for genetic counseling and clinical precision therapy by exploring the genetic etiology of a child with recurrent hypoglycemia convulsion accompanied by language retardation. METHODS: Peripheral blood samples were obtained from the proband, his sister and his parents. Whole genomic DNA was extracted and analyzed by the whole exon gene sequencing and confirmed by Sanger sequencing. RESULTS: The proband and his sister were found to carry compound heterozygous variants c.731T>A (p.M244L) and c.928G>A (p.G244S) of the GYS2 gene, which had not been reported in the past, the c.731T>A (p.M244L) site was derived from the maternal heterozygous mutation, while c.928G>A (p.G244S) site from the father heterozygous mutation. CONCLUSION The compound heterozygous variants c.731T>A (p.M244L) and c.928G>A (p.G244S) of the GYS2 gene were the genetic cause of glycogen storage syndrome type 0 in children, providing basis for family genetic counseling. When the patient had Hypoglycemia often accompanied with convulsions, which was easy to be misdiagnosed as seizures, and the antiepileptic treatment was ineffective. After genetic diagnosis, the seizure can be controlled by improving diet to maintain blood glucose stability.
Child ; Exons ; Glycogen ; Heterozygote ; Humans ; Mutation ; Pedigree ; Siblings

Objective To investigate the related factors for the survival of the patients with pancreatic cancer.Methods A total of 1 620 patients confirmed as pancreatic cancer admitted in Sun Yat-sen Memorial Hospital affiliated with Sun Yat-sen University,Tumor prevention and treatment center affiliated with Sun Yat-sen University and People's Hospital of Guangdong Province from 2004 to 2016 were retrospectively analyzed,and the effects of TNM staging,surgical treatment,palliative chemotherapy and postoperative assisted chemotherapy on the survival of the patients with pancreatic cancer were examined by life table and Log-rank test.Results The median survival time of all 1 620 cases was 7.15 months.The median survival time of TNM stage Ⅰ,Ⅱ,Ⅲ and Ⅳ was 12.50 months,10.12 months,9.56 months and 5.43 months,and there was statistically significant difference (P =0.001).The median survival time of cases who did not undergo surgery was 6.10 months,which of patients who underwent radical surgery was 13.67 months,and the difference was statistically significant (P =0.001).The median survival time of cases without chemotherapy was 5.55 months,which of patients who underwent palliative chemotherapy was 7.58 months,and the difference was statistically significant (P =0.001).The median survival time of cases with pure radical surgery without chemotherapy was 12.38 months,which of patients who underwent adjuvant chemotherapy was 14.50 months,and the difference was no statistically significant (P =0.561).Conclusions Early diagnosis followed closely by radical surgery is the key to prolong the survival of pancreatic cancer patients.And adjuvant chemotherapy for patients who lose surgery opportunity may improve clinical prognosis to a certain extent.

OBJECTIVETo evaluate relevant prognostic factors of unrelated single unit umbilical cord blood hematopoietic stem cell transplantation (sUCBT), and to explore the correlation between cryopreservation time of cord blood and cell viability and outcome of sUCBT.

METHODSRetrospective analysis of 137 patients undergoing sUCBT with cord blood provided by Shanghai Cord Blood Bank from Mar. 15, 2007 to Dec. 26, 2013 were performed in this study. The mean cryopreservation time of 137 units cord blood was 698(96-1968) days, with mean cell viability of 87.4% after thawing.

RESULTSNo statistical difference on cell viability, hematopoietic reconstitution, graft failure, acute graft versus host disease (GVHD) and overall survival (OS) was found between patients transfused with cord blood preserved below and above 2 years. The 5-year OS of patients transfused with cord blood preserved below and above 2 years were 55.6% and 67.9%, respectively (P=0.124). OS of the UCBT at 2011 and before, and after 2011 was 48.7% and 79.6%, respectively (P=0.001). Age above 16-year-old (RR=2.830, P=0.027) and UCBT at 2011 and before (RR=0.203, P<0.001) were two risk factors of treatment related mortality.

CONCLUSIONOutcome of sUCBT in China had significant improvement in recent 2 years. Cryopreservation time of cord blood had no statistical correlation to cell viability after thawing and clinical outcome.

Cell Survival ; China ; Cord Blood Stem Cell Transplantation ; Fetal Blood ; Graft vs Host Disease ; Hematopoietic Stem Cell Transplantation ; Humans ; Retrospective Studies

OBJECTIVETo investigate the impact of cryopreservation duration of umbilical cord blood (UCB) on quality of hematopoietic stem cell and outcome of clinical transplantation.

METHODS605 units of UCB which had been used in clinical transplantation were previously cryopreserved for 820 (88-2651) days in average. UCB was detected for total nucleated cell count, CD34+ cells count, cell recovery rate, cell viability and CFU-GM after thawing.

RESULTSNo statistical correlation was found between cryopreservation duration and cell recovery rate, cell viability. CFU-GM decreased along with the extension of cryopreservation duration (P=0.011), ranging between 109.6 and 105.7/1 × 10⁵. There was no significant difference on hematopoietic reconstitution time, graft failure, acute GVHD and overall survival among groups with different cryopreservation duration.

CONCLUSIONCryopreservation duration has no significant effect on cell recovery rate, cell viability and clinical transplantation outcome. Extension of cryopreservation duration may reduce CFU-GM of stem cells with fluctaion still in normal range. UCB could maintain cell viability and function to achieve satisfactory clinical transplantation outcome even when thawed after 3 to 7 years' cryopreservation.

Cell Count ; Cell Survival ; Cryopreservation ; Fetal Blood ; Graft vs Host Disease ; Granulocyte-Macrophage Progenitor Cells ; Hematopoietic Stem Cell Transplantation ; Hematopoietic Stem Cells ; Humans ; Treatment Outcome