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91.
Cetuximab and panitumumab bind the human epidermal growth factor receptor (EGFR). Although the chimeric cetuximab (IgG1) triggers antibody-dependent-cellular-cytotoxicity (ADCC) of EGFR positive target cells, panitumumab (a human IgG2) does not. The inability of panitumumab to trigger ADCC reflects the poor binding affinity of human IgG2 Fc for the FcγRIII (CD16) on natural killer (NK) cells. However, both human IgG1 and IgG2 bind the FcγRII (CD32A) to a similar extent. Our study compares the ability of T cells, engineered with a novel low-affinity CD32A131R-chimeric receptor (CR), and those engineered with the low-affinity CD16158F-CR T cells, in eliminating EGFR positive epithelial cancer cells (ECCs) in combination with cetuximab or panitumumab. After T-cell transduction, the percentage of CD32A131R-CR T cells was 74 ± 10%, whereas the percentage of CD16158F-CR T cells was 46 ± 15%. Only CD32A131R-CR T cells bound panitumumab. CD32A131R-CR T cells combined with the mAb 8.26 (anti-CD32) and CD16158F-CR T cells combined with the mAb 3g8 (anti-CD16) eliminated colorectal carcinoma (CRC), HCT116FcγR+ cells, in a reverse ADCC assay in vitro. Crosslinking of CD32A131R-CR on T cells by cetuximab or panitumumab and CD16158F-CR T cells by cetuximab induced elimination of triple negative breast cancer (TNBC) MDA-MB-468 cells, and the secretion of interferon gamma and tumor necrosis factor alpha. Neither cetuximab nor panitumumab induced Fcγ-CR T antitumor activity against Kirsten rat sarcoma (KRAS)-mutated HCT116, nonsmall-cell-lung-cancer, A549 and TNBC, MDA-MB-231 cells. The ADCC of Fcγ-CR T cells was associated with the overexpression of EGFR on ECCs. In conclusion, CD32A131R-CR T cells are efficiently redirected by cetuximab or panitumumab against breast cancer cells overexpressing EGFR.  相似文献   
92.
Fifty-seven patients took part in a controlled double-blind trial between tiopronin and D-penicillamine as basic treatment for rheumatoid arthritis. Thirty-nine (19 receiving tiopronin, 20 receiving D-penicillamine) completed the trial after 1 year. Both drugs resulted in a decrease of the erythrocyte sedimentation rate, Ritchie index, and Lee index and in a sparing effect on symptomatic antiinflammatory therapy. Improvement in these variables was statistically highly significant at any interval with tiopronin, but was sometimes less or not at all significant with D-penicillamine. Nevertheless, the difference in effects between the 2 drugs never reached statistical significance. Six patients receiving tiopronin and 6 receiving D-penicillamine were taken out of the experiment because of side effects.  相似文献   
93.

Background

Magnetocardiographic mapping (MCG) provides quantitative assessment of the magnetic field (MF) induced by cardiac ionic currents, is more sensitive to tangential currents, and measures vortex currents undetectable by ECG, with higher reported sensitivity of MCG ventricular repolarization (VR) parameters for earlier detection of acute myocardial ischemia. Aims of this study were to validate the feasibility of in‐hospital unshielded MCG and to assess repeatability and reproducibility of quantitative VR parameters, considering also possible gender‐ and age‐related variability.

Methods

MCG of 204 healthy subjects [114 males—mean age 43.4 ± 17.3 and 90 females—mean age 40.2 ± 15.7] was retrospectively analyzed, with a patented proprietary software automatically estimating twelve VR parameters derived from the analysis of the dynamics of the T‐wave MF extrema (five parameters) and from the inverse solution with the effective magnetic dipole model giving the effective magnetic vector components (seven parameters). MCG repeatability was calculated as coefficient of variation (CV) ±standard error of the mean (SEM). Reproducibility was assessed as intraclass correlation coefficient (ICC).

Results

The repeatability of all MCG parameters was 16 ± 1.2 (%) (average CV ± SEM). Optimal (ICC > 0.7) reproducibility was found for 11/12 parameters (mean values) and in 8/12 parameters (single values). No significant gender‐related difference was observed; six parameters showed a strong/moderate correlation with age.

Conclusion

Reliable MCG can be performed into an unshielded hospital ambulatory, with repeatability and reproducibility of quantitative assessment of VR adequate for clinical purposes. Wider clinical use is foreseen with the development of multichannel optical magnetometry.
  相似文献   
94.
Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) is a rare autosomal recessive organ-specific autoimmune disorder that is characterized by a variable combination of (i) chronic mucocutaneous candidiasis, (ii) polyendocrinopathy and/or hepatitis and (iii) dystrophy of the dental enamel and nails. We analyzed the AIRE (autoimmune regulator) gene in subjects who presented any symptom that has been associated with APECED, including candidiasis and autoimmune endocrinopathy. We observed that 83.3% of patients presented at least two of the three typical manifestations of APECED, while the remaining 16.7% of patients showed other signs of the disease. Analysis of the genetic diagnosis of these subjects revealed that a considerable delay occurs in the majority of patients between the appearance of symptoms and the diagnosis. Overall, the mean diagnostic delay in our patients was 10.2 years. These results suggest that molecular analysis of AIRE should be performed in patients with relapsing mucocutaneous candidiasis for early identification of APECED.  相似文献   
95.
Summary A case of Zollinger-EUison syndrome of multiple endocrine neoplasia type 1 (MEN 1) origin with hyperparathyroidism and with a rise in serum gastrin due to an unusual parathyroid gastrinoma has been investigated. The patient had multiple endocrine tumours (pituitary and parathyroid), but no evidence of pancreatic or duodenal gastrin-producing neoplasm. Radio-immunoassay, immunohistochemistry and electron microscopy showed gastrin in one parathyroid adenoma. These findings, together with a decrease of gastrinaemia after parathyroidectomy suggest that true gastrin was produced by parathyroid tumour cells and that they themselves may be the origin of the hypergastrinaemia. Our ultrastructural investigation extends these observations and the results are discussed.  相似文献   
96.
The osteoprotegerin-ligand (OPG-L) has been identified as the essential factor required for osteoclastogenesis, and its effects are prevented by the osteoprotegerin (OPG). The OPG-L/OPG balance plays a crucial role in coordinating the sequence of osteoclast and osteoblast differentiation during the bone remodeling. The aim of the study was to investigate if polymethylmethacrylate-based cements are able to modulate the expression of OPG-L/OPG in MG63 cells, which are known to have high levels of OPG and inducible expression of OPG-L. Four radio-opaque cements. namely Sulfix-60, CMW1, CMW2 and CMW3, were polymerized for either 1 h or 7 d. MG63 were incubated for 24 h with culture medium only, cement extracts and 2 microg/ml of human recombinant IL-1beta as positive control. An RT-PCR was performed to detect the OPG and OPG-L expression, and the house-keeping gene, GAPDH, was used as a reference for the semi-quantitative analysis. An increase in the OPG-L band density was observed for all cements, and consequently, the OPG-L/OPG ratio also increased. The ability of bone cements to induce the expression of OPG-L could be a co-factor in the development of osteolysis at the bone-cement interface.  相似文献   
97.
98.
Objective: Emerging evidence suggests that specific sub-populations of cancer cells with stem cell characteristics within the bulk of tumours are implicated in the pathogenesis of heterogeneous malignant tumours. The cells that drive tumour growth have been denoted cancer-initiating cells or cancer stem cells (hereafter CSCs). CSCs have been isolated initially from leukaemias and subsequently from several solid tumours including brain, breast, prostate, colon and lung cancer. This study aimed at isolating and characterising the population of tumour-initiating cells in non-small-cell lung cancer (NSCLC). Methods: Specimens of NSCLC obtained from 89 patients undergoing tumour resection at the Cancer National Institute of Naples were analysed. Three methods to isolate the tumour-initiating cells were used: (1) flow cytometry analysis for identification of positive cells for surface markers such as CD24, CD29, CD31, CD34, CD44, CD133 and CD326; (2) Hoechst 33342 dye exclusion test for the identification of a side-population characteristic for the presence of stem cells; (3) non-adherent culture condition able to form spheres with stem cell-like characteristics. Definition of the tumourigenic potential of the cells through soft agar assay and injection into NOD/SCID mice were used to functionally define (in vitro and in vivo) putative CSCs isolated from NSCLC samples. Results: Upon flow cytometry analysis of NSCLC samples, CD133-positive cells were found in 72% of 89 fresh specimens analysed and, on average, represented 6% of the total cells. Moreover, the number of CD133-positive cells increased markedly when the cells, isolated from NSCLC specimens, were grown as spheres in non-adherent culture conditions. Cells from NSCLC, grown as spheres, when assayed in soft agar, give rise to a 3.8-fold larger number of colonies in culture and are more tumourigenic in non-obese diabetic (NOD)/severe combined immunodeficiency (SCID) mice compared with the corresponding adherent cells. Conclusions: We have isolated and characterised a population of CD133-positive cells from NSCLC that is able to give rise to spheres and can act as tumour-initiating cells.  相似文献   
99.
Obsessive-Compulsive Disorder (OCD) and Tic Disorder (TD) are highly disabling and often comorbid conditions. Of note, the DSM-5 acknowledged a new ‘tic-related’ specifier for OCD, which might be referred to as Obsessive-Compulsive Tic Disorder (OCTD), raising new interest toward a better clinical characterisation of affected patients. Available literature indicates that early onset, male gender, sensory phenomena and obsessions of symmetry, aggressiveness, hoarding, exactness and sounds as well as comorbidity with Attention Deficit Hyperactivity Disorder (ADHD) may be of more frequent observation in patients with OCTD. In order to share expertise in the field from different perspectives, a multidisciplinary panel of Italian clinicians, specifically involved in the clinical care of OCD and TD patients, participated into a consensus initiative, aimed to produce a shared document. As a result, after having examined the most relevant literature, authors sought to critically identify and discuss main epidemiologic, socio-demographic and clinical features characterising OCTD patients, along with other specific aspects including Health-Related Quality-of-Life (HRQoL), economic consequences related with the condition and its management, as well as treatment-related issues, that need to be further investigated.  相似文献   
100.
The purpose of this investigation was to explore the potentiality of a novel animal model to be used for the in vivo evaluation of the ability of a drug delivery system to promote the passage through the blood–brain barrier (BBB) and/or to improve the brain localization of a bioactive compound. A Tween 80®-coated poly-l-lactid acid nanoparticles was used as a model of colloidal drug delivery system, able to trespass the BBB. Tacrine, administered in LiCl pre-treated rats, induces electrocorticographic seizures and delayed hippocampal damage. The toxic effects of tacrine-loaded poly-l-lactid acid nanoparticles (5 mg/kg), a saline solution of tacrine (5 mg/kg) and an empty colloidal nanoparticle suspension were compared following i.p. administration in LiCl-pre-treated Wistar rats. All the animals treated with tacrine-loaded nanoparticles showed an earlier outcome of CNS adverse symptoms, i.e. epileptic onset, with respect to those animals treated with the free compound (10 min vs. 22 min respectively). In addition, tacrine-loaded nanoparticles administration induced damage of neuronal cells in CA1 field of the hippocampus in all treated animals, while the saline solution of tacrine only in 60% of animals. Empty nanoparticles provided similar results to control (saline-treated) group of animals. In conclusion, the evaluation of time-to-onset of symptoms and the severity of neurodegenerative processes induced by the tacrine–lithium model of epilepsy in the rat, could be used to evaluate preliminarily the capability of a drug delivery system to trespass (or not) the BBB in vivo.  相似文献   
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