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In the big data environment of cloud computing, searchable encryption enables users to selectively access ciphertext data while improving data security. The existing multi-keyword-based encryption schemes have great shortcomings in terms of too large trapdoors and not supporting dynamic authorization of multiple users. Based on this, this paper proposes a multi-user multi-keyword searchable encryption scheme that supports user authorization. This solution supports the data owner to authorize users who access the data, and realizes that the authorized user sends the request for accessing the data to the data owner. Finally, the data owner generates a trapdoor and sends it to the server, and the server sends the result to the user after retrieval. In addition, this solution supports multi-users to dynamically add or withdraw users to ensure data security. This scheme proves that IND-CKA is safe and has the security of keyword trapdoor.

Aims: Succinic semialdehyde dehydrogenase (SSADH) deficiency is a neurometabolic disease in which the degradation of γ-aminobutyric acid (GABA) is impaired. The purpose of this study was to report two novel ALDH5A1 mutations responsible for SSADH deficiency in a Chinese family and the prenatal diagnosis of an at-risk fetus with DNA sequencing. Results: Genetic analysis of ALDH5A1, in a child with SSADH deficiency, parents, and 10 weeks’ gestation at-risk fetus and 100 healthy unrelated volunteers, was performed. The coding sequence and the intron/exon junctions of ALDH5A1 were analyzed by bidirectional DNA sequencing. The proband was identified to have a compound heterozygous mutations with c.496T>C (p.W166R) and c.589G>A (p.V197M). Each of his parents carried a deleterious mutation. DNA sequencing of chorionic villus revealed the fetus was a carrier, but not affected, and this was confirmed after birth by genetic analysis of umbilical cord blood and urine organic acid analysis. A study in 2003 described 35 mutations of ALDH5A1 in 54 unrelated families, and the current study and systematic literature review identified nine additional novel mutations in eight unrelated families bringing the total number of unique mutations of ALDH5A1 resulting in SSADH deficiency to 44, and the 44 mutations occur from exon 1 to exon 10. No mutational hotspots or prevalent mutations were observed, and all mutations appeared vital for the function of SSADH. Conclusions: Two novel ALDH5A1 mutations likely responsible for SSADH deficiency were identified, and DNA sequencing provided an accurate diagnosis for an at-risk fetus whose sibling had SSADH deficiency.

We investigated the feasibility of interleukin-2 receptor gamma (IL2Rγ) gene based on gene mutation analysis and pre-natal diagnosis of X-linked severe combined immunodeficiency (X-SCID). Blood samples of patients and their parents of X-SCID (family 1) and X-SCID (family 2) were collected. IL2Rγ gene sequences of the 2 families were analyzed using bi-directional direct sequencing by polymerase chain reaction. DNA sequence changes in the IL2Rγ gene exon region and shear zone were also analyzed. We also sequenced the IL2Rγ gene in 100 healthy individuals. Prenatal genetic diagnoses for a high-risk fetus in family 1 were performed by chorionic villus sampling after determining each family's genotypes. The suspect fe-male in family 1 underwent carrier detection. Two novel mutations of IL2Rγ gene were identified, including c.361-363delGAG (p.E121del) in the patient and his mother in family 1, and c.510-511insGAACT (p.W173X) heterozygous mutation in the proband's mother in family 2. These mutations were absent in the 100 controls. Prenatal diagnosis of early pregnancy in the female fetus of family 1 was performed; the fetus was heterozygous, which was confirmed at postnatal follow-up. The suspect female in family 1 showed no mutation in carrier detection. The novel p.E121del and p.W173X mutations in IL2Rγ may have been the primary causes of disease in 2 families with X-SCID. In couples with an X-SCID reproductive history, prenatal gene mutation analysis of IL2Rγ can effectively prevent the birth of children with X-SCID and carrier detection for suspected females.

Wiskott-Aldrich syndrome (WAS) is a rare X-linked primary immunodeficiency characterized by microthrombocytopenia, eczema, recurrent infections, and an increased incidence of autoimmunity and malignancies. The patients always have a severe clinical phenotype that can result in death if not diagnosed and treated early in life. The treatment of choice with the best outcome is hematopoietic stem cell transplantation, preferably from a matched related donor. But uncertain treatment effect and high treatment cost limit its clinical application. It is the best strategy that avoiding birth of a fetus with defect through prenatal diagnosis at present. This study aimed to analyze the mutation of WASP gene in 4 Chinese families with WAS and to provide prenatal diagnosis for the high-risk fetus.The probands of the four WAS families were all males, one of whom was deceased but had a family history and clinical datas integrated. All the patients were detected with blood routine tests, immunological tests and bone marrow examination. PCR and bilateral direct sequencing of PCR product was carried out in the regions of exon and exon-intron boundaries of WASP gene for 3 probands, 4 mothers and 100 unrelated healthy individuals as control. Prenatal diagnosis was provided for the two fetuses at the first trimester by mutation analysis.Four WASP gene mutations were detected: c.91AG (p.E31K), c.665CT (p.R211X), c.397GA (p.E133K), c.952-953delCC (p. P317fsX18), among which c.952-953delCC (p. P317fsX18) was first reported. Mothers in Family 2, 3 and 4 were carriers of WASP gene mutation, but family 1 was considered as a de-novo mutation. None of the 100 unaffected subjects had the above mutants. Prenatal diagnosis indicated that the fetus in family 2 was male and carried the same mutation as the proband, so the fetus was presumably to be a patient. The parents decided to receive an induced abortion. Following the termination of the pregnancy, the result of gene analysis of the aborted tissues was consistent with prenatal diagnosis. The fetus in family 3 was normal male confirmed by normal test results six months after birth.The 4 mutations of the WASP gene probably were causative to the families of WAS, among which c.952-953delCC was reported for the first time. Prenatal diagnosis by DNA sequencing is the effective method to avoid birth of WAS patient.

To evaluate the diagnostic feasibility of mutation analysis and prenatal genetic diagnosis genetic analysis of IL2RG gene in two families with a birth history of X-linked severe combined immunodeficiency (X-SCID).Blood samples of a male infant patient of X-SCID and his mother in family 1 and the parents of another deceased child with X-SCID in family 2 from January 2012 to February 2013 were collected.Eight exons comprising IL2RG open reading frame and their exon/intron boundaries were analyzed by bi-directional direct sequencing of polymerase chain reaction (PCR) products. Prenatal genetic diagnoses were performed by chorionic villus sampling after the genotypes of maternal probands were identified in family 1.Two mutations of IL2RG gene were identified in these two families. The c.361-363delGAG (p.E121del) mutation was identified in family 1. The c.510-511insGAACT (p.W173X) mutation appeared in family 2. The two mutations of c.361-363delGAG (p.E121del) and c.510-511insGAACT (p.W173X) were novel. The two novel mutations were absent in 100 normal controls. The pregnancy in family 1 continued and the infant showed no symptom of X-SCID at 1 year after birth. The aunt (II-3) of proband in family 1 was not a carrier. The female fetus in family 1 had no mutation.Two novel mutations of c.361-363delGAG (p.E121del) and c.510-511insGAACT (p.W173X) in IL2RG gene may be a major cause of disease in two families with X-SCID. And direct sequencing of IL2RG gene provides genetic counseling, prenatal diagnosis and carrier screening for families with X-SCID.

The purpose of this paper is to formulate a functional platform that supports the e-learning objectives: study individually and freely. The proposed platform is based on 3G mobile phone technology, it is integrated with operation system and application software developed with JAVA 2 micro edition and Flash Lite version 1.2, respectively. This platform gives learners the ability to learn anytime and anywhere. The 3G mobile phone is particularly suitable for developing personalized e-learning systems because of its mobility, portability wherever, whenever, whoever. The high speed data transmission of 3G mobile phone allows an optimal personalized e-learning environment.

CCK correlates with the generation and progression of pancreatic cancer. The research aims to construct eukaryotic expression plasmid pIRES2-EGFP/CCK (CCK pDNA) and transiently express it in COS-7 cells. Total RNA was extracted from porcine intestinal mucosa. RT-PCR was used to amplify the aimed segments CCKcDNA which was then digested with EcoR1 and BamH1 and inserted into a eukaryotic expression plasmid pIRES2-EGFP to construct CCK pDNA. The constructed plasmid was transfected into COS-7 cells by lepofectamine™2000-mediated transfer method. The expression of CCK in transfected COS-7 cells was detected 24, 48 and 72 h post-transfection with fluorescence microscopy and the expression level of CCK mRNA in transfected COS-7 cells was assayed by using RT-PCR. The results showed CCK pDNA was successfully constructed and expressed transiently in COS-7 cells. Green fluorescent protein could be detected in the COS-7 cells transfected with porcine CCK pDNA 24 h post-transfection. At 48th h post-transfection, the number of positive cells was increased significantly and much brighter green fluorescence could be detected. And 72 h post-transfection, the green fluorescence of positive cells became even stronger, while no green fluorescence was detected in the control group. The expression of CCK mRNA in the cells was detectable by using RT-PCR. In COS-7 cells transfected with CCK pDNA a high level of porcine CCK mRNA was detected while no expression of porcine CCKmRNA was found in the cells transfected with null plasmid. It was concluded CCK pDNA was expressed successfully in COS-7 cells, which lays a foundation for further research on the relationship between CCK and tumor.