In vitro study: binding of 99mTc-DPD to synthetic amyloid fibrils

Abstract This paper is an report of the investigation of the in vitro binding of 99mTc-DPD for synthetic amyloid fibrils used for the diagnosis of cardiac amyloidosis (CA), as compared with the use of 99mTc-HMDP and 99mTc-PPI. It also includes an inquiry into the role played by Ca2+ ions and serum proteins on binding to amyloid like materials, as well as the saturability and specificity of DPD for fibrils versus amorphous precipitates (AP). In the work, synthetic insulin fibrils (SIF) and AP were characterized by Congo red staining and TEM imaging. An equal amount of three radiopharmaceuticals were then added to fibrils in Ca2+ (0-4.2 mmol/L) or human serum (HS) adjoined samples and radiopharmaceutical uptake was assessed. To test the saturability of amyloid binding sites, a displacement assays with cold DPD was performed, while adding 50-1500 nmol of 99mTc-DPD to SIF or AP, saturation binding tests were subsequently carried out for evaluating its specificity for amyloid. Herein, synthetic fibrils and AP showed conformational differences at TEM and polarized microscopy analysis. In our study, 99mTc-DPD fibrils uptake was seen to be the highest and increased with calcium ions concentration. What is more, serum proteins reduced the bound fraction to the amyloid deposits of about 15%, and the Kd values of 90 nM and 114 nM relative to SIF and AP, respectively, did not significantly differ. We saw that 99mTc-DPD is the best seeker for amyloid fibrils in cardiac amyloidosis, and that Ca2+ concentration positively influenced DPD fibrils binding. Furthermore, the radioactivity bound to the serum protein clear up the idea of nuclide exchanging dynamic balance between amyloid and circulating proteins. Moreover, non-labeled DPD did not exert a competition for 99mTc-DPD binding sites, and, finally, DPD cannot be defined a radiopharmaceutical specific for amyloid deposits

Hypertermic Intrathoracic Chemotherapy (HITHOC) for thymoma: a narrative review on indications and results

Objective: With this narrative review, we retraced the history of hypertermic intrathoracic chemotherapy (HITHOC) since the beginning, analyzing literature on operative technique, feasibility and efficacy of this treatment. Moreover, we report the fifteen-year experience of our center in this relatively new technique, for what concerns both early postoperative results and long-term oncological outcomes. Background: Thymomas are frequently misdiagnosed and recognized in advanced stage, often with pleural dissemination, especially when not associated to Myasthenia Gravis that allows an early diagnosis during the initial assessment. Moreover, the natural history of locally advanced thymoma is characterized by a high rate of pleural or pericardial relapses. Surgery has always been considered a milestone in thymoma's treatment, even in case of serous dissemination or relapses, although his role as exclusive therapy does not guarantee an acceptable local disease control. In case of disseminated disease, different multidisciplinary protocols have been experimented, from chemotherapy to radiation therapy, alone or associated to surgery, in order to increase overall and disease-free survival, but the breakthrough happened in the early 90s with the introduction of HITHOC following surgery. Combination of surgery and HITHOC resulted in less toxic than systemic chemotherapy and providing a good local disease control in patients with stage IVa thymomas or thymoma's pleural recurrences. Methods: We searched PubMed for relevant literature, up to January 2020, on hypertermic intrapleural chemotherapy for thymomas (TPR or DNT), selecting only those reporting information about HITHOC protocol used, postoperative course and oncological outcomes. Conclusions: HITHOC is a safe and feasible procedure, with a very low complication rate and negligible systemic effects of chemotherapeutic agents, effective in controlling both TPR and DNT, in particular as regards local disease-free survival. Keywords: Hypertermic intrathoracic chemotherapy (HITHOC); thymoma; intracavitary chemotherapy; hyperthermia; redo-surgery

Diaphragm and lung-preserving surgery with hyperthermic chemotherapy for malignant pleural mesothelioma: A 10-year experience

Background: The best surgical treatment for malignant pleural mesothelioma is still under a debate, but recent evidence points toward a less-invasive approach to reduce morbidity and mortality. We reported our 10-year experience of a limited surgical approach associated with hyperthermic intrathoracic chemotherapy (HITHOC). Material and Methods: Between 2005 and 2014, patients with epithelioid or biphasic malignant pleural mesothelioma were treated with lung-diaphragm-pericardium-sparing pleurectomy associated with double-drug HITHOC; at least 3 cycles of adjuvant chemotherapy were then administered. The primary outcome examined was the feasibility of the procedure, whereas secondary outcomes were overall survival and disease-free interval. Results: Among 49 patients, 41 were male. Median age was 68 years (35-76 years). Histology was epithelioid in 43 cases. Pathologic stage I, II, III, and IV occurred in 12, 14, 20, and 3 cases, respectively. No intraoperative complications or postoperative mortality occurred, whereas morbidity rate was 46.9%. Median hospital stay was 8 days (5-45 days). Actuarial median overall survival was 22 months and a 1-, 2-, and 5-year survival accounted for 79.6%, 45.7%, and 9.9%, respectively. Disease-free survival after surgery was 62%, 37.5%, and 18.5% at 1, 2, and 5 years, respectively. Risk factors analysis for overall survival confirmed a significant role for early stages, epithelioid histology, and fibrinogen serum levels. Conclusions: Cytoreductive surgery associated with HITHOC and adjuvant chemotherapy appears feasible and safe, with no mortality and low morbidity. Preserving lung and diaphragmatic function might warrant an acceptable long-term outcome

Structure and dynamics of the integrin LFA-1 I-domain in the inactive state underlie its inside-out/outside-in signaling and allosteric mechanisms.

Lymphocyte function-associated antigen 1 (LFA-1) is an integrin that transmits information in two directions across the plasma membrane of leukocytes, in so-called outside-in and inside-out signaling mechanisms. To investigate the structural basis of these mechanisms, we studied the conformational space of the apo I-domain using replica-averaged metadynamics simulations in combination with nuclear magnetic resonance chemical shifts. We thus obtained a free energy landscape that reveals the existence of three conformational substates of this domain. The three substates include conformations similar to existing crystallographic structures of the low-affinity I-domain, the inactive I-domain with an allosteric antagonist inhibitor bound underneath α helix 7, and an intermediate affinity state of the I-domain. The multiple substates were validated with residual dipolar coupling measurements. These results suggest that the presence of three substates in the apo I-domain enables the precise regulation of the binding process that is essential for the physiological function of LFA-1.This study was supported by the Wellcome Trust and the BBSRC.This is the final version of the article. It first appeared from Cell Press via http://dx.doi.org/10.1016/j.str.2014.12.02

Type D personality in never depressed patients at their first acute coronary syndrome

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Photocatalytic Performance of Undoped and Al-Doped ZnO Nanoparticles in the Degradation of Rhodamine B under UV-Visible Light:The Role of Defects and Morphology

Quasi-spherical undoped ZnO and Al-doped ZnO nanoparticles with different aluminum content, ranging from 0.5 to 5 at% of Al with respect to Zn, were synthesized. These nanoparticles were evaluated as photocatalysts in the photodegradation of the Rhodamine B (RhB) dye aqueous solution under UV-visible light irradiation. The undoped ZnO nanopowder annealed at 400 °C resulted in the highest degradation efficiency of ca. 81% after 4 h under green light irradiation (525 nm), in the presence of 5 mg of catalyst. The samples were characterized using ICP-OES, PXRD, TEM, FT-IR, 27Al-MAS NMR, UV-Vis and steady-state PL. The effect of Al-doping on the phase structure, shape and particle size was also investigated. Additional information arose from the annealed nanomaterials under dynamic N2 at different temperatures (400 and 550 °C). The position of aluminum in the ZnO lattice was identified by means of 27Al-MAS NMR. FT-IR gave further information about the type of tetrahedral sites occupied by aluminum. Photoluminescence showed that the insertion of dopant increases the oxygen vacancies reducing the peroxide-like species responsible for photocatalysis. The annealing temperature helps increase the number of red-emitting centers up to 400 °C, while at 550 °C, the photocatalytic performance drops due to the aggregation tendency

Management of patients with early-stage colon cancer: guidelines of the Italian Medical Oncology Association

About 75% of colorectal cancers are diagnosed as early stage, in which radical surgery is achievable. In the last decade, in Italy, the overall incidence of colorectal cancer has remained stable, while mortality gradually decreased, which is attributable to early diagnosis and improved medical, surgical and locoregional treatments. The Italian Medical Oncology Association formulated guidelines to manage early-stage colon cancer, including screening, diagnosis, treatment and follow-up, which we herein present

Small-molecule sequestration of amyloid-β as a drug discovery strategy for Alzheimer's disease.

Disordered proteins are challenging therapeutic targets, and no drug is currently in clinical use that modifies the properties of their monomeric states. Here, we identify a small molecule (10074-G5) capable of binding and sequestering the intrinsically disordered amyloid-β (Aβ) peptide in its monomeric, soluble state. Our analysis reveals that this compound interacts with Aβ and inhibits both the primary and secondary nucleation pathways in its aggregation process. We characterize this interaction using biophysical experiments and integrative structural ensemble determination methods. We observe that this molecule increases the conformational entropy of monomeric Aβ while decreasing its hydrophobic surface area. We also show that it rescues a Caenorhabditis elegans model of Aβ-associated toxicity, consistent with the mechanism of action identified from the in silico and in vitro studies. These results illustrate the strategy of stabilizing the monomeric states of disordered proteins with small molecules to alter their behavior for therapeutic purposes