白细胞因子对人粒细胞超氧阴离子自由基释放的影响

我们研究了受到白细胞因子(LF)和(或)刀豆球蛋白A(Con A)刺激的人粒细胞超氧阴离子自由基(O_2~-)的释放,当单独用LF或Con A刺激粒细胞时,能释放一定数量的O_2~-,若将粒细胞与一低浓度LF_1预温育,则能加强Con A刺激的粒细胞的释放O_2~-作用,并能缩短释放O_2~-的延迟时间,结果表明LF对粒细胞有激活作用,这可能与LF的疗效机理有关。     

Inactivation of Icmt inhibits transformation by oncogenic K-Ras and B-Raf

Isoprenylcysteine carboxyl methyltransferase (Icmt) methylates the carboxyl-terminal isoprenylcysteine of CAAX proteins (e.g., Ras and Rho proteins). In the case of the Ras proteins, carboxyl methylation is important for targeting of the proteins to the plasma membrane. We hypothesized that a knockout of Icmt would reduce the ability of cells to be transformed by K-Ras. Fibroblasts harboring a floxed Icmt allele and expressing activated K-Ras (K-Ras-Icmt^flx/flx) were treated with Cre-adenovirus, producing K-Ras-Icmt^Δ/Δ fibroblasts. Inactivation of Icmt inhibited cell growth and K-Ras–induced oncogenic transformation, both in soft agar assays and in a nude mice model. The inactivation of Icmt did not affect growth factor–stimulated phosphorylation of Erk1/2 or Akt1. However, levels of RhoA were greatly reduced as a consequence of accelerated protein turnover. In addition, there was a large Ras/Erk1/2-dependent increase in p21^Cip1, which was probably a consequence of the reduced levels of RhoA. Deletion of p21^Cip1 restored the ability of K-Ras-Icmt^Δ/Δ fibroblasts to grow in soft agar. The effect of inactivating Icmt was not limited to the inhibition of K-Ras–induced transformation: inactivation of Icmt blocked transformation by an oncogenic form of B-Raf (V599E). These studies identify Icmt as a potential target for reducing the growth of K-Ras– and B-Raf–induced malignancies.     

Proteomics and pathway analyses of the milk fat globule in sheep naturally infected by Mycoplasma agalactiae provide indications of the in vivo response of the mammary epithelium to bacterial infection

Milk fat globules (MFGs) are vesicles released in milk as fat droplets surrounded by the endoplasmic reticulum and apical cell membranes. During formation and apocrine secretion by lactocytes, various amounts of cytoplasmic crescents remain trapped within the released vesicle, making MFGs a natural sampling mechanism of the lactating cell contents. With the aim of investigating the events occurring in the mammary epithelium during bacterial infection, the MFG proteome was characterized by two-dimensional difference gel electrophoresis (2-D DIGE), SDS-PAGE followed by shotgun liquid chromatography-tandem mass spectrometry (GeLC-MS/MS), label-free quantification by the normalized spectral abundance factor (NSAF) approach, Western blotting, and pathway analysis, using sheep naturally infected by Mycoplasma agalactiae. A number of protein classes were found to increase in MFGs upon infection, including proteins involved in inflammation and host defense, cortical cytoskeleton proteins, heat shock proteins, and proteins related to oxidative stress. Conversely, a strikingly lower abundance was observed for proteins devoted to MFG metabolism and secretion. To our knowledge, this is the first report describing proteomic changes occurring in MFGs during sheep infectious mastitis. The results presented here offer new insights into the in vivo response of mammary epithelial cells to bacterial infection and open the way to the discovery of protein biomarkers for monitoring clinical and subclinical mastitis.     

Solitary extramedullary plasmacytoma of the thyroid gland associated with multinodular goiter: case report and review of the literature

Solitary extramedullary plasmacytoma (SEP) is a rare malignant neoplasm arising from plasma cells most commonly occurring in the nasal cavity, nasopharynx and larynx. Thyroid involvement is rare and less than 75 cases of SEP of the thyroid gland have been reported to date. A 74-year-old woman with an history of multinodular goiter presented with dysphonia and painful neck swelling, related to a rapidly growing nodule in the right thyroid lobe. Thyroid function tests showed subclinical hypothyroidism; no evidence of Hashimoto's disease was found. Ultrasound confirmed the presence of an isoechoic nodule, 35 mm in diameter, with a CDIII vascular pattern. FNAC showed a monotonous population of atypical cells, interpreted as suspicious for malignant neoplasia (Thyr. 4). The patient underwent total thyroidectomy. Histopathological examination showed a unencapsulated neoplasm composed of atypical tumour cells characterized by abundant cytoplasm and eccentric nuclei. At immunohistochemistry, tumour cells revealed diffuse reactivity for CD138 and CD45RB and predominant staining for kappa chains. Pan-cytokeratins, TTF1, thyreoglobulin, calcitonin, CD20 and CD79a were negative. Clinically, a complete multiple myeloma workup was negative. On this basis, a definitive diagnosis of SEP was made. At 16 months follow-up, the patient showed good clinical conditions without evidence of multiple myeloma. In conclusion, SEP should be considered in the differential diagnosis of a rapidly enlarging thyroid nodule. Clinical correlation and immunocytochemistry are crucial in avoiding pitfalls. Surgery remains the best modality of treatment whenever the lesion is localized and easily removable.     

p16 ink4a and HPV L1 immunohistochemistry is helpful for estimating the behavior of low-grade dysplastic lesions of the cervix uteri

As only a minority of low-grade dysplastic lesions of the cervix uteri will eventually progress to carcinoma, predicting the behavior of these lesions could be of high value in clinical practice. The aim of the study was to evaluate p16 ink4a and L1 as immunohistochemical markers of the biologic potentiality of low-grade dysplasia of the uterine cervix. The study included 38 conization specimens with coexisting cervical intraepithelial neoplasia grade 1 (CIN1) and 3 (CIN3) (group A) and 28 punch biopsies from women with CIN1 and proven spontaneous regression in the follow-up (group B). In group A, all CIN3 were p16 ink4a positive (p16+) and L1 negative (L1-). The CIN1 of this group were p16+L1- and p16+L1+ in 68.42% and 31.57%, respectively. No other expression pattern was found in this group. In group B, the p16+L1-, p16+L1+, p16-L1+, and p16-L1- patterns were found in 3.57%, 25%, 14.29%, and 57.14%, respectively. Overall, 96.29% p16+L1- CIN1 were found in group A, whereas all the p16-L1+ and p16-L1- CIN1 were found in group B. A significant difference between staining pattern distributions of group A and B was observed (P<0.0001). The results of the study show that p16 ink4a and L1 immunohistochemistry can be helpful for estimating the biologic potentiality of low-grade squamous cervical lesions. Particularly in cases in which the grade of the lesion is morphologically difficult to assess, the p16/L1 expression pattern could be useful for planning the clinical management of these women.