Cloning, expression, and functional characterization of in-house prepared human leukemia inhibitory factor

Leukemia inhibitory factor [LIF] plays important roles in cellular proliferation, growth promotion and differentiation of various types of target cells. In addition, LIF influences bone metabolism, cachexia, neural development, embryogenesis and inflammation. Human LIF [hLIF] is an essential growth factor for the maintenance of mouse embryonic stem cells [ESCs] and induced pluripotent stem cells [iPSCs] in a pluripotent, undifferentiated state. In this experimental study, we cloned hLIF into the pENTR-D/TOPO entry vector by a TOPO reaction. Next, hLIF was subcloned into the pDEST17 destination vector by the LR reaction, which resulted in the production of a construct that was transferred into E. coli strain Rosetta-gami[TM] 2[DE3] pLacI competent cells to produce the His6-hLIF fusion protein. This straightforward method produced a biologically active recombinant hLIF protein in E. coli that has long-term storage ability. This procedure has provided rapid, cost effective purification of a soluble hLIF protein that is biologically active and functional as measured in mouse ESCs and iPSCs in vitro. Our results showed no significant differences in function between laboratory produced and commercialized hLIF

[Comparison of p53 expression between occupationally exposed to ionizing radiation and control group]

Various stresses such as ionizing radiation can increase cellular damage, especially to nuclear DNA. To protect cellular damages, normal regulatory genes [such as Tp53 tumor suppressor] become activated. Accordingly, in this study, the p53 gene and its expression among employees occupationally exposed to low doses of ionizing radiation were compared with a selected control group. Using an ELISA kit, the amount of p53 protein in the blood serum of case and control groups was measured. Statistical analysis was performed using student t-test procedure. As a case group, 42 healthy individuals [with a mean age of 37.8 +/- 1.3 years] occupationally dealing with different kind of radiation sources in Atomic Energy Organization of Iran were chosen. As a control group, 16 healthy unexposed volunteers [with a mean age of 34.5 +/- 2.0 years] who were matched for age, sex and smoking habits were selected. A 2 ml aliquot of heparinized peripheral blood was collected from each case. The results of this research indicate the higher levels of p53 expression in occupationally radiation group. Moreover, the work history or smoking had no effects on p53 expression. Although the absorbed doses were below the permissible limits, this study confirms the role of low-level chronic exposure in increasing p53 expression among occupationally radiation workers. These results confirm that monitoring of radiation workers should not only be solely based on physical dosimetry, but also on the biological indicators, which have the advantage of measuring the individual radiation damage

Hemangioma of the spermatic cord: a case report

Hemangioma of the spermatic cord is a benign, extremely rare tumor. We report a case of spermatic cord hemangioma presenting with a painless mass in the left hemiscrotum. Physical examination revealed a non-tender nontransilluminating irregular mass in the left hemiscrotum, above and clearly separate from the left testis. After surgical removal of the mass arising from the spermatic cord, histologic examination showed a benign vascular tumor consistent with cavernous hemangioma. To our knowledge, only a few cases of spermatic cord hemangioma have been previously reported in the literature