998 resultados para Anti-CCP Ab
Resumo:
Summary. Olive oil and fish products from the south of Hispania and North Africa played an important role in the Roman economy. The authors call attention to the asymmetrical distribution of archaeological data available on this subject, in particular the location of amphora kilns, and try to give an explanation, based on the evolution of European archaeology in the twentieth century.
Resumo:
Cooperation in joint enterprises can easily break down when self-interests are in conflict with collective benefits, causing a tragedy of the commons. In such social dilemmas, the possibility for contributors to invest in a common pool-rewards fund, which will be shared exclusively among contributors, can be powerful for averting the tragedy, as long as the second-order dilemma (i.e. withdrawing contribution to reward funds) can be overcome (e.g. with second-order sanctions). However, the present paper reveals the vulnerability of such pool-rewarding mechanisms to the presence of reward funds raised by defectors and shared among them (i.e. anti-social rewarding), as it causes a cooperation breakdown, even when second-order sanctions are possible. I demonstrate that escaping this social trap requires the additional condition that coalitions of defectors fare poorly compared with pro-socials, with either (i) better rewarding abilities for the latter or (ii) reward funds that are contingent upon the public good produced beforehand, allowing groups of contributors to invest more in reward funds than groups of defectors. These results suggest that the establishment of cooperation through a collective positive incentive mechanism is highly vulnerable to anti-social rewarding and requires additional countermeasures to act in combination with second-order sanctions.
Resumo:
BACKGROUND: A combination of radioimmunotherapy (RIT) and radiotherapy (RT) should allow one to increase the dose of radiation targeting a particular tumour without the concomitant increase of toxic side effects. This might be obtained if the dose limiting side effect of each individual radiation therapy concerned different organs. METHODS: Six patients with limited liver metastatic disease from colorectal cancer were treated with 6.9 GBq (range 4.7 to 8.4 GBq) 131I-labelled anti-CEA MAb F(ab')2 fragments combined with 20 Gy RT to the liver. Both treatments were given in close association, according to timing schedules evaluated in animals that gave the best results. RESULTS: Reversible bone marrow and liver toxicity was observed in 6 and 5 patients, respectively. Three patients who first received 20 Gy RT to the liver, showed a significant platelet drop upon completion of RT. Repeat computerized tomography (CT) after 2 months showed a minor response in 1 patient and stable disease in 3 patients. CONCLUSION: The study shows potential ways of combining RIT and RT, suggesting that this combination is feasible for the treatment of liver metastases.
Resumo:
PPARalpha and PPARbeta are expressed in the mouse epidermis during fetal development, but their expression progressively disappears after birth. However, the expression of PPARbeta is reactivated in adult mice upon proliferative stimuli, such as cutaneous injury. We show here that PPARbeta protects keratinocytes from growth factor deprivation, anoikis and TNF-alpha-induced apoptosis, by modulating both early and late apoptotic events via the Akt1 signaling pathway and DNA fragmentation, respectively. The control mechanisms involve direct transcriptional upregulation of ILK, PDK1, and ICAD-L. In accordance with the anti-apoptotic role of PPARbeta observed in vitro, the balance between proliferation and apoptosis is altered in the epidermis of wounded PPARbeta mutant mice, with increased keratinocyte proliferation and apoptosis. In addition, primary keratinocytes deleted for PPARbeta show defects in both cell-matrix and cell-cell contacts, and impaired cell migration. Together, these results suggest that the delayed wound closure observed in PPARbeta mutant mice involves the alteration of several key processes. Finally, comparison of PPARbeta and Akt1 knock-out mice reveals many similarities, and suggests that the ability of PPARbeta to modulate the Akt1 pathway has significant impact during skin wound healing.
Resumo:
Anti-angiogenic therapies have recently enriched the therapeutic armentarium against the most common cancers. Among these, bevacizumab, a monoclonal antibody against vascular endothelial growth factor, is currently used most frequently. While the addition of bevacizumab to chemotherapy improves overall survival in first and second line treatment of metastatic colorectal cancer, its effect in metastatic breast cancer is limited to improvements in tumor response and progression-free-survival. In non-small-cell lung cancer, the positive results of a first American phase III study have not been confirmed by a second European study and are subject to controversies. A summary of the data concerning anti-angiogenic therapies in these three cancers is presented including safety information.
Resumo:
To avoid the exclusive use of rodent monoclonal antibodies (MAbs) in patients for the detection of tumors by immunoscintigraphy and for radioimmunotherapy, swine MAbs were produced that are directed against carcinoembryonic antigen (CEA). Spleen cells from 2 pigs immunized with purified colon carcinoma CEA were fused with a nonsecreting mouse myeloma cell line by conventional methods, except that a particularly long immunization protocol and large amounts of spleen and myeloma cells were used. Of 1,200 growing hybrids tested, 20 were found initially to produce antibodies binding to radiolabeled CEA. Seven stable clones producing anti-CEA MAbs for more than 6 months were derived from these hybrids by repeated subcloning. The pig origin of the seven MAbs was demonstrated in a solid-phase CEA enzyme immunoassay where anti-pig immunoglobin (Ig) antibodies coupled to peroxidase gave a positive reaction while anti-mouse Ig antibodies were entirely negative. All swine MAbs were of the IgG isotype. Three anti-CEA MAbs showed no cross-reactivity with granulocytes, while four others gave various degrees of reactivity with different granulocyte glycoproteins. Competitive binding to CEA performed for two purified swine MAbs showed that they recognized two different epitopes. The affinity constants measured for these two MAbs by Scatchard plot on purified CEA were high (1.2 X 10(9) and 1.2 X 10(10) liter/mol). One of the MAbs was tested in vivo for tumor localization by injection, after radiolabeling, in nude mice bearing human colon carcinoma xenograft. High ratios of tumor to normal tissue were obtained with mean values of 10.5 for intact MAbs and of 26.8 for F(ab')2 fragments of the porcine MAb. The results showed that heterofusion with this particular protocol can be used to produce swine MAbs of high affinity and specificity for a well-defined tumor marker. These reagents may have an important clinical utility, particularly in patients who became sensitized to mouse immunoglobulins.
Resumo:
BACKGROUND: The preservation of globe integrity has always been a major concern during the treatment of retinoblastoma for fear of extraocular or metastatic spread. Intravitreal chemotherapy has been attempted as a desperate salvage therapy only for eyes with refractory retinoblastoma. Published data on the safety and efficacy of this route are, however, limited. METHODS: A modified technique of intravitreal injection in eyes with retinoblastoma is described. All children with retinoblastoma who received one or more intravitreal injections using this technique were retrospectively reviewed concerning ocular complications of the injection procedure as well as clinical or histopathological evidence of tumour spread. RESULTS: 30 eyes of 30 children with retinoblastoma received a total of 135 intravitreal injections, with a median follw-up duration of 13.5 months. No extraocular spread was seen on clinical follow-up in any patients and there was no tumour contamination of the retrieved entry sites histopathologically analysed among the five enucleated eyes. No significant ocular side effects were observed except transient localised vitreous haemorrhage (3/135). CONCLUSION: This technique is potentially safe and effective at a low cost and may play a promising role, especially in the treatment of recurrent and/or resistant vitreous disease in retinoblastoma, as an alternative to enucleation and/or external beam radiotherapy. However, this treatment should not replace the primary standard of care of retinoblastoma and should not be considered in group E eyes. Its application should be approved by an ophthalmological-oncological team and it should be performed by an experienced eye surgeon in a tertiary referral centre after careful selection of a tumour-free injection site.
Resumo:
Passive immunization against β-amyloid (Aβ) has become an increasingly desirable strategy as a therapeutic treatment for Alzheimer's disease (AD). However, traditional passive immunization approaches carry the risk of Fcγ receptor-mediated overactivation of microglial cells, which may contribute to an inappropriate proinflammatory response leading to vasogenic edema and cerebral microhemorrhage. Here, we describe the generation of a humanized anti-Aβ monoclonal antibody of an IgG4 isotype, known as MABT5102A (MABT). An IgG4 subclass was selected to reduce the risk of Fcγ receptor-mediated overactivation of microglia. MABT bound with high affinity to multiple forms of Aβ, protected against Aβ1-42 oligomer-induced cytotoxicity, and increased uptake of neurotoxic Aβ oligomers by microglia. Furthermore, MABT-mediated amyloid plaque removal was demonstrated using in vivo live imaging in hAPP((V717I))/PS1 transgenic mice. When compared with a human IgG1 wild-type subclass, containing the same antigen-binding variable domains and with equal binding to Aβ, MABT showed reduced activation of stress-activated p38MAPK (p38 mitogen-activated protein kinase) in microglia and induced less release of the proinflammatory cytokine TNFα. We propose that a humanized IgG4 anti-Aβ antibody that takes advantage of a unique Aβ binding profile, while also possessing reduced effector function, may provide a safer therapeutic alternative for passive immunotherapy for AD. Data from a phase I clinical trial testing MABT is consistent with this hypothesis, showing no signs of vasogenic edema, even in ApoE4 carriers.
Resumo:
Human inhibitor NF-κB kinase 2 (hIKK-2) is the primary component responsible for activating NF-κB in response to various inflammatory stimuli. Thus, synthetic ATP-competitive inhibitors for hIKK-2 have been developed as anti-inflammatory compounds. We recently reported a virtual screening protocol (doi:10.1371/journal.pone.0016903) that is able to identify hIKK-2 inhibitors that are not structurally related to any known molecule that inhibits hIKK-2 and that have never been reported to have anti-inflammatory activity. In this study, a stricter version of this protocol was applied to an in-house database of 29,779 natural products annotated with their natural source. The search identified 274 molecules (isolated from 453 different natural extracts) predicted to inhibit hIKK-2. An exhaustive bibliographic search revealed that anti-inflammatory activity has been previously described for: (a) 36 out of these 453 extracts; and (b) 17 out of 30 virtual screening hits present in these 36 extracts. Only one of the remaining 13 hit molecules in these extracts shows chemical similarity with known synthetic hIKK-2 inhibitors. Therefore, it is plausible that a significant portion of the remaining 12 hit molecules are lead-hopping candidates for the development of new hIKK-2 inhibitors.
Resumo:
Immunotherapy-responsive autoimmune CNS syndromes linked to antibodies targeting surface neuronal antigens lack reliable biomarkers of disease activity. We report serial cerebral (18)FDG PET studies in a woman with AMPA receptor (AMPA-R) autoimmune limbic encephalitis. During her follow-up, despite an aggressive immunotherapy, she displayed a persistent, predominantly left hippocampal FDG hypermetabolism, in the absence of CNS inflammatory signs. Brain metabolism abnormalities regressed after increasing antiepileptic treatment, correlating with a moderate clinical improvement. Brain (18)F-FDG PET could thus represent a useful complementary tool to orient the clinical follow-up.
Resumo:
BACKGROUND AND AIMS: Mannan-binding lectin (MBL) and ficolins are microbial pattern recognition molecules that activate the lectin pathway of complement. We previously reported the association of MBL deficiency with anti-Saccharomyces cerevisiae antibodies (ASCA) in patients with Crohn's disease (CD). However, ASCA are also frequently found in MBL-proficient CD patients. Here we addressed expression/function of ficolins and MBL-associated serine protease-2 (MASP-2) regarding potential association with ASCA. METHODS: ASCA titers and MBL, ficolin and MASP-2 concentrations were determined by ELISA in the serum of patients with CD, ulcerative colitis (UC), and in healthy controls. MASP-2 activity was determined by measuring complement C4b-fixation. Anti-MBL autoantibodies were detected by ELISA. RESULTS: In CD and UC patients, L-ficolin concentrations were significantly higher compared to healthy controls (p<0.001 and p=0.029). In contrast, H-ficolin concentrations were slightly reduced in CD and UC compared to healthy controls (p=0.037 for UC vs. hc). CD patients with high ASCA titers had significantly lower H-ficolin concentrations compared to ASCA-low/negative CD patients (p=0.009). However, MASP-2 activity was not different in ASCA-negative and ASCA-positive CD patients upon both, ficolin- or MBL-mediated MASP-2 activation. Finally, anti-MBL autoantibodies were not over-represented in MBL-proficient ASCA-positive CD patients. CONCLUSIONS: Our results suggest that low expression of H-ficolin may promote elevated ASCA titers in the ASCA-positive subgroup of CD patients. However, unlike MBL deficiency, we found no evidence for low expression of serum ficolins or reduced MASP-2 activity that may predispose to ASCA development.
Resumo:
We report on a 70-year-old woman with partial complex status epilepticus who was initially diagnosed with herpes simplex-2 (HSV-2) encephalitis, based on brain magnetic resonance imaging (MRI) findings, cerebrospinal fluid (CSF) lymphocytic pleocytosis and HSV-2 DNA detection by polymerase chain reaction (PCR) in the CSF, but without improvement on intravenous acyclovir. Anti-Ri antibodies were positive and computed tomography (CT) investigations revealed a small cell carcinoma at biopsy suggesting paraneoplastic encephalitis. The outcome was unfavourable and the autopsy showed typical features of paraneoplastic encephalitis but no evidence of viral inclusions. This case report is interesting because: (1) it is the first report of an autopsy proven paraneoplastic widespread encephalitis with anti-Ri antibodies; (2) despite a positive HSV-2 PCR in the CSF, there was no sign of herpetic infections of the nervous system; and (3) it illustrates the fact that if paraneoplastic antibodies are usually good markers of the underlying tumour, they are not always predictive of neurological deficits.