食品免检制之反思--以风险治理为视角

"三鹿毒奶粉"事件爆发之后被废止的食品免检制是产品免检制在食品监管领域的延伸。实行产品免检制的初衷是为了减轻企业负担、减少行政成本、摆脱地方的行政干预,然而,免检制在实际运行中渐露弊端。围绕免检制的绩效与正当性问题,存在反对与赞成两种意见。在引入风险理论之后可以发现,食品免检制忽视了食品行业在风险治理次序中的优先位置,忽视了食品风险的社会建构性,忽视了食品免检的制度风险,忽视了风险治理应有的分散、复合体系。这些忽视使食品免检制在风险社会中难获正当性,而无论其绩效如何。

免检班级制:现代职业教育教学制度创新——以广东省对外贸易职业技术学校商务英语专业1371班为例

高等教育不断扩大招生,中职学校降低招生门槛,中职生综合素质参差不齐。因此,中职生班级管理难度增大,中职教育中传统的班级管理模式已经不能适应新的教育理念和当今社会对中职人才素质的需求。以广东省对外贸易职业技术学校商务英语专业中由广东省轻工进出口股份有限公司冠名的1371班为首个免检试点班级(以下简称"免检班级")为例,从制定免检班级制度、组建免检班级管理团队和贯通免检班级培养模式三个方面对"免检班级制"进行初步建构。

Combining targeted therapy and immune checkpoint inhibitors in the treatment of metastatic melanoma

Melanoma is the deadliest form of skin cancer and has an incidence that is rising faster than any other solid tumor. Metastatic melanoma treatment has considerably progressed in the past five years with the introduction of targeted therapy(BRAF and MEK inhibitors) and immune checkpoint blockade(anti-CTLA4, anti-PD-1, and anti-PD-L1). However, each treatment modality has limitations. Treatment with targeted therapy has been associated with a high response rate, but with short-term responses. Conversely, treatment with immune checkpoint blockade has a lower response rate, but with longterm responses. Targeted therapy affects antitumor immunity, and synergy may exist when targeted therapy is combined with immunotherapy. This article presents a brief review of the rationale and evidence for the potential synergy between targeted therapy and immune checkpoint blockade. Challenges and directions for future studies are also proposed.

Fueling the engine and releasing the break: combinational therapy of cancer vaccines and immune checkpoint inhibitors

Immune checkpoint inhibitors are increasingly drawing much attention in the therapeutic development for cancer treatment. However, many cancer patients do not respond to treatments with immune checkpoint inhibitors, partly because of the lack of tumor-infiltrating effector T cells. Cancer vaccines may prime patients for treatments with immune checkpoint inhibitors by inducing effector T-ceU infiltration into the tumors and immune checkpoint signals. The combination of cancer vaccine and an immune checkpoint inhibitor may function synergistically to induce more effective antitumor immune responses, and clinical trials to test the combination are currently ongoing.

The association of altered RARβ gene expression with the cervical lesion pathogenesis

Objective:Previous reports have shown that the gene promoter region of retinoic acid receptor β(RARβ) was hypermethylated in cervical carcinoma,implying the inhibition of gene transcription.The aim of this study was to investigate the association of cervical cancer development with the RARβ gene expression at the mRNA and protein level to assess the impact of RARβ as a marker for early detection of the cancer.Methods:We collected 126 cases of formalin fixed and paraffin embedded cervical tissue specimens as well as 37 cases of fresh tissue samples from women with cervicitis,cervical intraepithelial neoplasia(CIN) and cervical squamous cell carcinoma(CSCC).The RARβ mRNA and protein expression was detected by quantitative RT-PCR and immunohistochemistry,respectively.Results:(1) The mRNA expression of RARβ in CIN and cervical cancer was markedly decreased compared to cervicitis with a statistically very significant difference,but no difference was found between CIN and cervical cancer.(2) RARβ protein was normally expressed in the epithelial cells of cervicitis and partially lost in a few cases,but with the development of cervical lesion pathogenesis and cancer,a significant loss of protein expression was detected in CIN(38%) and CSCC(57%) compared to cervicitis(P < 0.01).Conclusion:The downregulation of RARβ transcription or loss of protein expression is an important indicator of cervical cancer and its precursur lesions.The detection of RARβ expression coupled with aberrant methylation of the gene may become a biomarker for the early prognosis or diagnosis of the cancer.

Preparation and Characterization of Monoclonal Antibodies against VP1 Protein of Foot-and-mouth Disease Virus O/China99

Monoclonal antibodies (McAbs) 1A9 and 9F12 against Foot-and-mouth disease virus (FMDV) serotype O were produced by fusing SP2/0 myeloma cells with splenocyte from the mouse immunized with O/China99. Both McAbs reacted with O/China99 but not with Asia 1, as determined by immunohistochemistry assay. The microneutralization titer of the McAbs 1A9 and 9F12 were 640 and 1 280, respectively. Both McAbs contain kappa light chains, but the McAbs 1A9 and 9F12 were IgG1 and IgM, respectively. In order to define the McAbs binding epitopes, the reactivity of these McAbs against VP1, P20 and P14 were examined using indirect ELISA, the result showed that both McAbs reacted with VP1 and P20. McAbs may be used for further studies of vaccine, diagnostic methods, prophylaxis, etiological and immunological researches on FMDV.

Enhanced vasoconstriction to α_1 adrenoceptor autoantibody in spontaneously hypertensive rats

Autoimmune activities have been implicated in the pathogenesis of hypertension.High levels of autoantibodies against the second extracellular loop of α1-adrenoceptor(α1-AR autoantibody,α1-AA) are found in patients with hypertension,and α1-AA could exert a α1-AR agonist-like vasoconstrictive effect.However,whether the vasoconstrictive effect of α1-AA is enhanced in hypertension is unknown.Using aortic rings of spontaneously hypertensive rats(SHR) and normotensive Wistar-Kyoto(WKY) rats,we observed the vasoconstrictive responses to α1-AA with phenylephrine(α1-AR agonist) as a positive control drug.Aortic nitrotyrosine levels were also measured by ELISA and immunohistochemistry.The results showed that the aortic constrictive responses to α1-AA and phenylephrine(both 1 nmol L-1-10 μmol L-1) were greater in SHR than in WKY rats.Endothelial denudation or L-NAME(a non-selective NOS inhibitor)(100 μmol L-1) increased α1-AA- or phenylephrine-induced vasoconstrictions both in SHR and WKY.However,selective iNOS inhibitor 1400W(10 μmol L-1) enhanced the α1-AA-induced aortic constriction in WKY,but not in SHR.The aortic nitrotyrosine level was significantly higher in SHR than WKY,as shown by both ELISA and immunohistochemistry.These results indicate that the vasoconstrictive response to α1-AA is enhanced in SHR,and this altered responsiveness is due to endothelial dysfunction and decreased NO bioavailability.The study suggests an important role of α1-AR autoimmunity in the pathogenesis and management of hypertension especially in those harboring high α1-AA levels.