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171.
BACKGROUND: Interleukin (IL)‐12 is a cytokine that can exert regulatory effects on T and NK cells. This study was designed to identify potential developmental and reproductive hazards associated with IL‐12p40 knockout in mice. METHODS: In the combined fertility and teratology study, female F0 C57/BL6 wild‐type control mice and female F0 C57/BL6 IL‐12p40 homozgyous knockout mice were assessed for estrous cyclicity, sperm, and mating parameters. Pregnant females were euthanized on gestation day (GD) 18 and their fetuses were assessed for external, visceral, and skeletal development. In the peri and postnatal development study, the F1 wild‐type control and IL‐12p40 knockout mice were assessed for developmental landmarks, sexual development, passive avoidance, motor activity, and morris water maze. RESULTS: The IL‐12p40 knockout male mice exhibited decreased testis weights when compared to the wild‐type control group; however, this finding was not considered adverse, as it had no apparent functional effects on mating, fertility, and pregnancy rates or sperm motility. The IL‐12p40 knockout group exhibited effects on estrous cycle length, passive avoidance, morris water maze, and motor activity when compared to the wild‐type control group. However, since these findings were small in magnitude, transient and/or had no apparent effects on subsequent growth and development, they were not considered adverse. CONCLUSIONS: These results demonstrate that although IL‐12p40 homozygous knockout in mice exhibited effects on developmental and reproductive parameters, these effects were relatively minor and were not considered adverse. Birth Defects Res (Part B) 92:102–110, 2011. © 2011 Wiley‐Liss, Inc.  相似文献   
172.
Tumors are infiltrated by macrophages, T and B-lymphocytes, which may favor tumor development by promoting angiogenesis, growth and invasion. The aim of this study was to investigate the clinical relevance of the relative amount of macrophages (CD68+), T-cells (CD3+) and B-cells (CD20+) at the invasive front of breast carcinomas, and the expression of matrix metalloproteases (MMPs) and their inhibitors (TIMPs) either at the invasive front or at the tumor center. We performed an immunohistochemical study counting CD3, CD20 and CD68 positive cells at the invasive front, in 102 breast carcinomas. Also, tissue sections were stained with MMP-2, -9, -11, -14 and TIMP-2 antibodies, and immunoreactivity location, percentage of reactive area and intensity were determined at the invasive front and at the tumor center. The results showed that an increased CD68 count and CD68/(CD3+CD20) ratio were directly associated with both MMP-11 and TIMP-2 expression by mononuclear inflammatory cells at the tumor center (p = 0.041 and p = 0.025 for CD68 count and p = 0.001 and p = 0.045 for ratio, respectively for MMP-11 and TIMP-2). In addition, a high CD68/(CD3+CD20) ratio (>0.05) was directly associated with a higher probability of shortened relapse-free survival. Multivariate analysis revealed that CD68/(CD3+CD20) ratio was an independent factor associated with distant relapse-free survival (RR: 2.54, CI: (1.23–5.24), p<0.01). Therefore, CD68/(CD3+CD20) ratio at the invasive front could be used as an important prognostic marker.  相似文献   
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Human papillomavirus (HPV) is the causative agent of human cervical cancer and has been associated with oropharyngeal squamous cell carcinoma development. Although prophylactic vaccines have been developed, there is a need to develop new targeted therapies for individuals affected with malignant infected lesions in these locations, which must be tested in appropriate models. Cutaneous beta HPV types appear to be involved in skin carcinogenesis. Virus oncogenicity is partly achieved by inactivation of retinoblastoma protein family members by the viral E7 gene. Here we show that the E7 protein of cutaneous beta HPV5 binds pRb and promotes its degradation. In addition, we described an in vivo model of HPV-associated disease in which artificial human skin prepared using primary keratinocytes engineered to express the E7 protein is engrafted onto nude mice. Expression of E7 in the transplants was stably maintained for up to 6 months, inducing the appearance of lesions that, in the case of HPV16 E7, histologically resembled human anogenital lesions caused by oncogenic HPVs. Moreover, it was confirmed through biomarker expression analysis via immunodetection and/or quantitative PCR from mRNA and miRNA that the 16E7-modified engrafted skin shares molecular features with human HPV-associated pretumoral and tumoral lesions. Finally, our findings indicate a decrease of the in vitro capacity of HPV5 E7 to reduce pRb levels in vivo, possibly explaining the phenotypical differences when compared with 16E7-grafts. Our model seems to be a valuable platform for basic research into HPV oncogenesis and preclinical testing of HPV-associated antitumor therapies.  相似文献   
175.
Background:  Using quadruple clarithromycin‐containing regimens for Helicobacter pylori eradication is controversial with high rates of macrolide resistance. Aim:  To evaluate antibiotic resistance rates and the efficacy of empirical and tailored nonbismuth quadruple (concomitant) therapy in a setting with cure rates <80% for triple and sequential therapies. Methods:  209 consecutive naive H. pylori‐positive patients without susceptibility testing were empirically treated with 10‐day concomitant therapy (proton pump inhibitors (PPI), amoxicillin 1 g, clarithromycin 500 mg, and metronidazole 500 mg; all drugs b.i.d.). Simultaneously, 89 patients with positive H. pylori culture were randomized to receive triple versus concomitant therapy for clarithromycin‐susceptible H. pylori, and sequential versus concomitant therapy for clarithromycin‐resistant strains. Eradication was confirmed with 13C‐urea breath test or histology 8 weeks after completion of treatment. Results:  Per‐protocol (PP) and intention‐to‐treat eradication rates after empirical concomitant therapy without susceptibility testing were 89% (95%CI:84–93%) and 87% (83–92%). Antibiotic resistance rates were: clarithromycin, 20%; metronidazole, 34%; and both clarithromycin and metronidazole, 10%. Regarding clarithromycin‐susceptible H. pylori, concomitant therapy was significantly better than triple therapy by per protocol [92% (82–100%) vs 74% (58–91%), p = 0.05] and by intention to treat [92% (82–100%) vs 70% (57–90%), p = 0.02]. As for antibiotic‐resistant strains, eradication rates for concomitant and sequential therapies were 100% (5/5) vs 75% (3/4), for clarithromycin‐resistant/metronidazole‐susceptible strains and 75% (3/4) vs 60% (3/5) for dual‐resistant strains. Conclusions:  Empirical 10‐day concomitant therapy achieves good eradication rates, close to 90%, in settings with multiresistant H. pylori strains. Tailored concomitant therapy is significantly superior to triple therapy for clarithromycin‐susceptible H. pylori and at least as effective as sequential therapy for resistant strains.  相似文献   
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Visceral leishmaniasis (VL) in patients receiving immunosuppressant drugs for autoimmune disease has been on the rise. It is important—but difficult—to know when cure has been achieved in these patients since the withdrawal of immunosuppressants during antileishmania treatment is commonly required, and there is a risk of relapse when immunosuppression is restored. The prevalence of asymptomatic infection among those immunosuppressed for autoimmune disease is also uncertain. The present work describes how cytokine release assays can be used to confirm the cure of VL, and to determine the prevalence of asymptomatic infection, in such patients. After collection of blood from volunteers (n = 108), SLA-stimulation of peripheral blood mononuclear cell cultures and of whole blood was found to induce the production of different combinations of cytokines that served to confirm recovery from VL, and asymptomatic Leishmania infection. Indeed, cure was confirmed in 14 patients, all of whom showed a specific Th1 immune response against Leishmania, and the prevalence of asymptomatic infection was determined as 21.27%. Cytokine profiles could be used to manage VL in patients with autoimmune disease, and to identify and better protect those with asymptomatic infection who are at risk of developing this disease.  相似文献   
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