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1.
J Photochem Photobiol B ; 253: 112871, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38402658

RESUMO

Programmed cell death or apoptosis is a critically important mechanism of tissue remodeling and regulates conditions such as cancer, neurodegeneration or stroke. The aim of this research article was to assess the caged Z-DEVD-aminoluciferin substrate for in vivo monitoring of apoptosis after ischemic stroke in TLR2-deficient mice and their TLR2-expressing counterparts. Postischemic inflammation is a significant contributor to ischemic injury development and apoptosis, and it is modified by the TLR2 receptor. Caged Z-DEVD-aminoluciferin is made available for bioluminescence enzymatic reaction by cleavage with activated caspase-3, and therefore it is assumed to be capable of reporting and measuring apoptosis. Apoptosis was investigated for 28 days after stroke in mice which ubiquitously expressed the firefly luciferase transgene. Middle cerebral artery occlusion was performed to achieve ischemic injury, which was followed with magnetic resonance imaging. The scope of apoptosis was determined by bioluminescence with caged Z-DEVD-aminoluciferin, immunofluorescence with activated caspase-3, flow cytometry with annexin-V and TUNEL assay. The linearity of Z-DEVD-aminoluciferin substrate dose effect was shown in the murine brain. Z-DEVD-aminoluciferin was validated as a good tool for monitoring apoptosis following adequate adjustment. By utilizing bioluminescence of Z-DEVD-aminoluciferin after ischemic stroke it was shown that TLR2-deficient mice had lower post-stroke apoptosis than TLR2-expressing wild type mice. In conclusion, Z-DEVD-aminoluciferin could be a valuable tool for apoptosis measurement in living mice.


Assuntos
Luciferina de Vaga-Lumes/análogos & derivados , AVC Isquêmico , Oligopeptídeos , Receptor 2 Toll-Like , Camundongos , Animais , Caspase 3/metabolismo , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/metabolismo , Apoptose
2.
Soft Matter ; 20(6): 1263-1274, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38236145

RESUMO

External stimuli can tune the uptake and release of guest molecules in microgels. Especially their pH responsiveness makes microgels exciting candidates for drug delivery systems. When both microgel and guest molecules are pH-responsive, predicting the electrostatically driven uptake can be complex since the ionization depends on many parameters. In this work, we performed Metropolis Monte Carlo simulations while systematically varying the pK of the monomers, the concentrations of microgel and guest molecules to obtain a better understanding of the uptake of weak cationic oligomers as a model for oligopeptides into a weak anionic polyelectrolyte microgel. Further, we varied the chain length of the oligomers. The polyelectrolyte networks can take up oligomers when both the network and the oligomers are charged. The presence of both species in the system leads to a mutual enhancement of their ionization. The uptake induces a release of counterions and results in complex formation between the oligomers and the network, leading to the collapse of the networks. Longer oligomers enhance the ionization of the network and, therefore, the complexation. A higher microgel concentration increases the uptake only around the isoelectric point but prevents the uptake due to lower entropy gain at counterion release at higher pH. The results give an insight into the uptake of cationic oligomers into oppositely charged polyelectrolyte microgels and provide hints for the design of anionic microgels as carriers for guest molecules e.g. antimicrobial peptides.


Assuntos
Microgéis , Polieletrólitos , Método de Monte Carlo , Oligopeptídeos , Concentração de Íons de Hidrogênio
3.
Int J Biol Macromol ; 244: 125369, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37321435

RESUMO

The adhesion forces of cells to peptide-coated functionalized materials were assessed through the Single Cell Force Spectroscopy (SCFS) technique in order to develop a methodology that allows the fast selection of peptide motifs that favor the interaction between cells and the biomaterial. Borosilicate glasses were functionalized using the activated vapor silanization process (AVS) and subsequently decorated with an RGD- containing peptide using the EDC/NHS crosslinking chemistry. It is shown that the RGD-coated glass induces larger attachment forces on mesenchymal stem cell cultures (MSCs), compared to the bare glass substrates. These higher forces correlate well with the enhanced adhesion of the MSCs observed on RGD-coated substrates through conventional adhesion cell cultures and inverse centrifugation tests. The methodology based on the SCFS technique presented in this work constitutes a fast procedure for the screening of new peptides or their combinations to select candidates that may enhance the response of the organism to the implant of the functionalized biomaterials.


Assuntos
Materiais Biocompatíveis , Oligopeptídeos , Adesão Celular/fisiologia , Análise Espectral/métodos , Materiais Biocompatíveis/química , Oligopeptídeos/química , Microscopia de Força Atômica/métodos , Propriedades de Superfície
5.
Int J Pharm ; 637: 122868, 2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-36958606

RESUMO

Follicle stimulating hormone (FSH) is widely used for the treatment of female infertility, where the level of FSH is suboptimal due to which arrest in follicular development and anovulation takes place. Currently, only parenteral formulations are available for FSH in the market. Due to the drawbacks of parenteral administration and the high market shares of FSH, there is a need for easily accessible oral formulation. Therefore, enteric coated capsules filled with FSH loaded nanostructured lipid carriers (NLCs) or liposomes were prepared. Preliminary studies such as circular dichroism, SDS-PAGE, FTIR and ELISA were conducted to analyze FSH. Prepared formulations were optimized with respect to the size, polydispersity index, zeta potential, and entrapment efficiency using the design of experiments. Optimized formulations were subjected to particle counts and distribution analysis, TEM analysis, in vitro drug release, dissolution of enteric coated capsules, cell line studies, everted sac rat's intestinal uptake study, pharmacokinetics, pharmacodynamics, and stability studies. In the case of liposomes, RGD conjugation was done by carbodiimide chemistry and conjugation was confirmed by FTIR, 1HNMR and Raman spectroscopy. The prepared formulations were discrete and spherical. The release of FSH from enteric coated capsules was slow and sustained. The increased permeability of nano-formulations was observed in Caco-2 monoculture as well as in Caco-2 and Raji-B co-culture models. NLCs and liposomes showed an improvement in oral bioavailability and efficacy of FSH in rats. This may be due to mainly chylomicron-assisted lymphatic uptake of NLCs; whereas, in the case of liposomes, RGD-based targeting of ß1 integrins of M cells on Peyer's patches may be the main reason for the better effect by FSH. FSH was found to be stable chemically and conformationally. Overall, the study reveals the successful development and evaluation of FSH loaded NLCs and liposomes.


Assuntos
Portadores de Fármacos , Nanoestruturas , Humanos , Ratos , Feminino , Animais , Portadores de Fármacos/química , Lipossomos , Hormônio Foliculoestimulante , Células CACO-2 , Nanoestruturas/química , Administração Oral , Cápsulas , Oligopeptídeos , Tamanho da Partícula
6.
Phys Med Biol ; 68(8)2023 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-36944252

RESUMO

Objective. Simplified calculation approaches and geometries are usually adopted for salivary glands (SGs) dosimetry. Our aims were (i) to compare different dosimetry methods to calculate SGs absorbed doses (ADs) following [18F]-PSMA-1007 injection, and (ii) to assess the AD variation across patients and single SG components. Approach. Five patients with prostate cancer underwent sequential positron-emission tomography/computed tomography (PET/CT) acquisitions of the head and neck, 0.5, 2 and 4 h after [18F]-PSMA-1007 injection. Parotid and submandibular glands were segmented on CT to derive SGs volumes and masses, while PET images were used to derive Time-Integrated Activity Coefficients. Average ADs to single SG components or total SG (tSG) were calculated with the following methods: (i) direct Monte Carlo simulation with GATE/GEANT4 considering radioactivity in the entire PET/CT field-of-view (MC) or in the SGs only (MCsgo); (ii) spherical model (SM) of OLINDA/EXM 2.1, adopting either patient-specific or standard ICRP89 organ masses (SMstd); (iii) ellipsoidal model (EM); (iv) MIRD approach with organS-factors from OLINDA/EXM 2.1 and OpenDose collaboration, with or without contribution from cross irradiation originating outside the SGs. The maximum percent AD difference across SG components (δmax) and across patients (Δmax) were calculated.Main results. Compared to MC, ADs to single SG components were significantly underestimated by all methods (average relative differences ranging between -11.9% and -30.5%).δmaxvalues were never below 25%. The highestδmax(=702%) was obtained with SMstd. Concerning tSG, results within 10% of the MC were obtained only if cross-irradiation from the remainder of the body or from the remainder of the head was accounted for. The Δmaxranged between 58% and 78% across patients.Significance. Simple geometrical models for SG dosimetry considerably underestimated ADs compared to MC, particularly if neglecting cross-irradiation from neighboring regions. Specific masses of single SG components should always be considered given their large intra- and inter-patient variability.


Assuntos
Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Radiometria , Humanos , Masculino , Oligopeptídeos , Radiometria/métodos , Compostos Radiofarmacêuticos , Glândulas Salivares/diagnóstico por imagem
7.
Anticancer Res ; 43(1): 449-453, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36585198

RESUMO

BACKGROUND/AIM: To test the correlation of 68Ga-PSMA-11 uptake and the expression of PSMA (prostatic specific membrane antigen) with the Gleason score, apparent diffusion coefficient (ADC) and pharmacokinetic parameters obtained from dynamic contrast agent-enhanced MRI/PET. PATIENTS AND METHODS: Forty newly diagnosed, therapy naïve patients with prostatic carcinoma (PC) (mean age of 56.7, range=34-79), who were referred for 68Ga-PSMA-11-PET/MRI for primary staging and had undergone radical prostatectomy (RAPE) were included in this prospective study. Their blood samples were tested for serum levels of prostate-specific antigen (PSA) and proPSA. The patients' prostates were evaluated using whole-mount sections, which helped determine the extent and grade of the tumor; tests were performed to determine immunohistochemical PSMA expression. RESULTS: A correlation between PSMA expression and the accumulation of 68Ga-PSMA-11 was found using the Spearman correlation coefficient (p=0.0011). A stronger correlation was found between Gleason patterns 3 or 4 and PSMA expression (p=0.06). Furthermore, the correlation of Gleason score with the overall 68Ga-PSMA-11 accumulation within the tumor or non-tumor tissue was found to be significant (p=0.0157). A significant relation was found only with the Kep elimination rate constant, which was stronger in Gleason pattern 4 than in Gleason pattern 3. A weaker correlation was found between the accumulation of 68Ga-PSMA-11 and Ktrans in Gleason pattern 4: the most significant relation being between ADCmin and Gleason pattern 3 and 4 (p=0.0074). The total size of the tumor correlated with levels of proPSA (p<0.0001), and its extra prostatic extension correlated with levels of proPSA (p<0.0001). CONCLUSION: 68Ga-PSMA-11 correlates well with the expression of PSMA. Gleason pattern 3 and 4 had a higher correlation with 68Ga-PSMA-11 levels than did Gleason pattern 5. Either no correlation, or a weak correlation, was established with pharmacokinetics.


Assuntos
Carcinoma , Neoplasias da Próstata , Masculino , Humanos , Pessoa de Meia-Idade , Próstata/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Gradação de Tumores , Estudos Prospectivos , Oligopeptídeos , Ácido Edético , Radioisótopos de Gálio , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/cirurgia , Neoplasias da Próstata/metabolismo , Tomografia por Emissão de Pósitrons , Imageamento por Ressonância Magnética
8.
Braz. j. oral sci ; 22: e237270, Jan.-Dec. 2023. ilus
Artigo em Inglês | LILACS, BBO | ID: biblio-1413378

RESUMO

Opiorphin is a pentapeptide, which could be isolated from human fluids and has a decreasing effect on pain. Aim: Since lichen planus is a chronic mucocutaneous disease, which causes pain or burning feeling in the oral mucosa, this study aimed to compare salivary opiorphin levels of oral lichen planus (OLP) patients with healthy subjects. Methods: This case-control study, was performed on 24 patients with OLP lesions and 21 healthy subjects. After collecting unstimulated saliva, opiorphin levels were compared between two groups through statistical analyses. Results: There was not any significant difference between OLP patients and healthy subjects according to salivary opiorphin concentration (p=0.378). Also, in the OLP group, opiorphin concentration was not significantly different between males and females (p=0.601). Analytical analysis could not show any remarkable difference between various severity of OLP lesions regarding to salivary opiorphin levels (p=0.653). Conclusion: In this study, salivary opiorphin levels was not significantly different between patients with OLP and healthy subjects; however, more studies are suggested for better assessment of salivary opiorphin levels in various types of OLP lesions and its correlation with pain severity


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Oligopeptídeos , Dor , Saliva , Líquen Plano Bucal
9.
Int J Mol Sci ; 23(20)2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36293282

RESUMO

Transmembrane glycoprotein integrins play crucial roles in biochemical processes, and by their inhibition or activation, different signal pathways can be disrupted, leading to abnormal physiological functions. We have previously demonstrated the inhibitory effect of glyphosate herbicide's active ingredient on cell adhesion and its αvß3 integrin antagonist effect. Therefore, it appeared particularly exciting to investigate inhibition of glyphosate and its metabolites on a wider range of Arg-Gly-Asp (RGD) binding integrins, namely αvß3, α5ß1 and αllbß3. Thus, the purpose of this study was to assess how extended the inhibitory effect observed for glyphosate on the integrin αvß3 is in terms of other RGD integrins and other structurally or metabolically related derivatives of glyphosate. Five different experimental setups using enzyme-linked immunosorbent assays were applied: (i) αvß3 binding to a synthetic polymer containing RGD; (ii) αvß3 binding to its extracellular matrix (ECM) protein, vitronectin; (iii) α5ß1 binding to the above polymer containing RGD; (iv) αllbß3 binding to its ECM protein, fibrinogen and (v) αvß3 binding to the SARS-CoV-2 spike protein receptor binding domain. Total inhibition of αvß3 binding to RGD was detected for glyphosate and its main metabolite, aminomethylphosphonic acid (AMPA), as well as for acetylglycine on α5ß1 binding to RGD.


Assuntos
COVID-19 , Herbicidas , Humanos , Integrina alfaVbeta3/metabolismo , Vitronectina , Herbicidas/farmacologia , SARS-CoV-2 , Oligopeptídeos/química , Ensaio de Imunoadsorção Enzimática , Fibrinogênio , Polímeros
10.
Drug Deliv ; 29(1): 2815-2823, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36047255

RESUMO

Acute myocardial infarction (AMI) is one of the most common ischemic heart diseases. However, lack of sufficient drug concentration (in the ischemic heart) is the major factor of treatment failure. It is urgent for researchers to engineer novel drug delivery systems to enhance the targeted delivery of cardioprotective agents. The aim of the present study was to investigate the anti-AMI ability of calycosin (CAL) and tanshinone (TAN) co-loaded; mitochondrion-targeted tetrapeptide (MTP) and cyclic arginyl-glycyl-aspartic acid (RGD) peptide co-modified nano-system.: We prepared CAL and TAN combined lipid-polymer hybrid nano-system, and RGD was modified to the system to achieve RGD-CAL/TAN NS. MTP-131 was conjugated with PEG and modified onto the nanoparticles to achieve dual ligands co-modified MTP/RGD-CAL/TAN NS. The physicochemical properties of nano-systems were characterized. The AMI therapy ability of the systems was investigated in AMI rats' model. The size of MTP/RGD-CAL/TAN NS was 170.2 ± 5.6 nm, with a surface charge of -18.9 ± 1.9 mV. The area under the curve (AUC) and blood circulation half-life (T1/2) of MTP/RGD-CAL/TAN NS was 178.86 ± 6.62 µg·min/mL and 0.47 h, respectively. MTP/RGD-CAL/TAN NS exhibited the most significant infarct size reduction effect of 22.9%. MTP/RGD-CAL/TAN NS exhibited the highest heart accumulation and best infarct size reduction effect, which could be used as a promising system for efficient treatment of cardiovascular diseases.


Assuntos
Infarto do Miocárdio , Nanopartículas , Animais , Ratos , Abietanos , Isoflavonas , Lipídeos/química , Mitocôndrias , Infarto do Miocárdio/tratamento farmacológico , Nanopartículas/química , Oligopeptídeos/química , Peptídeos Cíclicos , Polímeros/química
11.
Nan Fang Yi Ke Da Xue Xue Bao ; 42(8): 1143-1148, 2022 Aug 20.
Artigo em Chinês | MEDLINE | ID: mdl-36073212

RESUMO

OBJECTIVE: To investigate the value of 68Ga-labeled prostate specific membrane antigen (PSMA) PET/CT for assessing tumor load in primary lesions for risk stratification and predicting metastasis of newly diagnosed prostate cancer (PCa). METHODS: We retrospectively analyzed the data of 36 patients (mean age 71.3 ± 8.6 years, range 56 to 89 years) with newly diagnosed PCa undergoing 68Ga-PSMA-I&T PET/CT from June 2018 to July 2019. SUVmax and SUVmean of the primary lesions were measured, and the primary PSMA tumor volume (PSMA-TV) and total lesion PSMA (TL-PSMA) were automatically measured and calculated in all the patients. The correlations of primary SUVmax, PSMA-TV, and TL-PSMA with PSA and Gleason score (GS) were analyzed, and SUVmax, PSMA-TV and TL-PSMA of the primary lesions were compared among different PCa subgroups. RESULTS: SUVmax, PSMA-TV and TL-PSMA of the primary lesions were all correlated with PSA and GS (P < 0.05). PCa subgroup analysis showed that SUVmax, PSMA-TV and TL-PSMA were all significantly higher in patients with PSA >20 ng/mL than in those with PSA ≤20 ng/mL (P < 0.001), and were higher in patients with a GS ≥8 than in those with a GS ≤7 (P < 0.001). PSMA-TV and TL-PSMA were significantly higher in patients with tumor metastasis than in those without metastasis (P < 0.001), while SUVmax did not differ significantly with tumor metastasis. SUVmax (P=0.002), PSMA-TV (P < 0.001), and TL-PSMA (P < 0.001) were all significantly higher in high-risk group than in low-to moderate-risk group. CONCLUSION: PSMA-TV and TL-PSMA of 68Ga-PSMA-I&T PET/CT have potential value in predicting risk stratification and metastasis of newly diagnosed PCa.


Assuntos
Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias da Próstata , Idoso , Idoso de 80 Anos ou mais , Ácido Edético , Isótopos de Gálio , Radioisótopos de Gálio , Humanos , Masculino , Pessoa de Meia-Idade , Oligopeptídeos , Antígeno Prostático Específico , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Estudos Retrospectivos , Carga Tumoral
12.
J Agric Food Chem ; 70(39): 12418-12429, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36129441

RESUMO

Oligopeptides (Thr-His-Leu-Pro-Lys (THLPK), His-Pro-Leu-Lys (HPLK), Leu-Pro-Lys (LPK), His-Leu-Lys (HLK), and Leu-His-Lys (LHK)) are newly identified from rapeseed napin (Brassica napus) protein-derived hydrolysates with the capability of upregulating glucose transporter-4 (GLUT4) expression and translocation. However, whether each of them enhances GLUT4 expression and translocation and their specific mechanisms remain unclear. Here, we assess the effects of the oligopeptides against insulin resistance (IR) and oxidative stress in hepatocytes and screen out the most antidiabetic one. Specifically, compared with other oligopeptides, LPK not only remarkably elevated glucose consumption to 8.45 mmol/L protein; superoxide dismutase (SOD) activity to 319 U/mg protein; GLUT4 expression and translocation; and phosphorylated level of insulin receptor substrate-1 (IRS-1), phosphatidylinositol 3-kinase (PI3K), and protein kinase B (Akt) (P < 0.05) but also remarkably attenuated the reactive oxygen species (ROS) level to 2255, lactate dehydrogenase (LDH) activity to 20.5 U/mg protein, malondialdehyde (MDA) content to 241 nmol/mg protein, and NO content to 1302 µmol/mL protein (P < 0.05). These findings demonstrated that antidiabetic oligopeptide LPK possessed the most potential to protect HepG2 cells from IR and oxidative stress via activating IRS-1/PI3K/Akt/GLUT4 and regulating common oxidative markers in vitro.


Assuntos
Brassica napus , Resistência à Insulina , Brassica napus/genética , Brassica napus/metabolismo , Glucose/metabolismo , Proteínas Facilitadoras de Transporte de Glucose/metabolismo , Células Hep G2 , Humanos , Hipoglicemiantes , Proteínas Substratos do Receptor de Insulina/genética , Proteínas Substratos do Receptor de Insulina/metabolismo , Lactato Desidrogenases/metabolismo , Malondialdeído , Oligopeptídeos/metabolismo , Oligopeptídeos/farmacologia , Estresse Oxidativo , Fosfatidilinositol 3-Quinase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
13.
Front Public Health ; 10: 942800, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35923949

RESUMO

Objective: To explore the cost-effectiveness of degarelix acetate for injection (degarelix) compared to leuprorelin in prostate cancer (Pca) castration treatment from Chinese healthcare system perspective. Methods: A Markov model, adapted from the one established in Finland was conducted for the cost-effectiveness analysis of degarelix and leuprorelin for Pca treatment. The main data were derived from global phase III clinical trials of degarelix (CS21), published study and expert surveys. Outcomes, utility and costs of prostate cancer patients were calculated on a 30-year time horizon. The CS21 study based population of intention-to-treat (ITT) population and three scenarios were modeled. Taking three times of the Gross domestic product (GDP) per capita (242,928 yuan, 2021) as the acceptable threshold for cost-effectiveness. One-way and probabilistic sensitivity analyses were performed on key parameters, including transition probabilities, costs, utility, and discount rate to test the robustness of the model. Results: Base case analysis for ITT population revealed that total costs of degarelix and leuprorelin were 566,226 yuan and 489,693 yuan, while the total quality-adjusted life years (QALYs) were 5.19 and 4.51 during the 30-year time horizon, resulting an incremental cost effectiveness ratio (ICER) of 112,674 yuan/QALY which was 1.39 times the GDP per capita, lower than willingness-to-pay level of three times the GDP per capita. The results for scenario analyses revealed that compared to leuprorelin, degarelix for Pca treatment in China was cost-effective. One-way sensitivity analysis showed that the model was most sensitive to price of 80 mg degarelix, utility of 1st-line therapy, hazard ratio of PSA recurrence, price of 3.75 mg leuprorelin, response rate of docetaxel per cycle, and discount rate of cost. In probabilistic sensitivity analysis, compared to leuprorelin, the probability of degarelix to be cost-effective was 53 and 81% for willingness-to-pay threshold of one and three times the GDP per capita. Conclusion: Compared to leuprorelin, degarelix for prostate cancer treatment is cost-effective. Moreover, scenario, one-way, and probabilistic sensitivity analyses revealed that the model was robust.


Assuntos
Leuprolida , Neoplasias da Próstata , China , Ensaios Clínicos Fase III como Assunto , Análise Custo-Benefício , Humanos , Leuprolida/uso terapêutico , Masculino , Oligopeptídeos , Neoplasias da Próstata/tratamento farmacológico
14.
Molecules ; 27(12)2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35744985

RESUMO

The aim of this work is to compare [68Ga]Ga-PSMA-11 and [18F]PSMA-1007 PET/CT as imaging agents in patients with prostate cancer (PCa). Comparisons were made by evaluating times and costs of the radiolabeling process, imaging features including pharmacokinetics, and impact on patient management. The analysis of advantages and drawbacks of both radioligands might help to make a better choice based on firm data. For [68Ga]Ga-PSMA-11, the radiochemical yield (RCY) using a low starting activity (L, average activity of 596.55 ± 37.97 MBq) was of 80.98 ± 0.05%, while using a high one (H, average activity of 1436.27 ± 68.68 MBq), the RCY was 71.48 ± 0.04%. Thus, increased starting activities of [68Ga]-chloride negatively influenced the RCY. A similar scenario occurred for [18F]PSMA-1007. The rate of detection of PCa lesions by Positron Emission Tomography/Computed Tomography (PET/CT) was similar for both radioligands, while their distribution in normal organs significantly differed. Furthermore, similar patterns of biodistribution were found among [18F]PSMA-1007, [68Ga]Ga-PSMA-11, and [177Lu]Lu-PSMA-617, the most used agent for RLT. Moreover, the analysis of economical aspects for each single batch of production corrected for the number of allowed PET/CT examinations suggested major advantages of [18F]PSMA-1007 compared with [68Ga]Ga-PSMA-11. Data from this study should support the proper choice in the selection of the PSMA PET radioligand to use on the basis of the cases to study.


Assuntos
Radioisótopos de Gálio , Neoplasias da Próstata , Ácido Edético , Isótopos de Gálio , Humanos , Masculino , Niacinamida/análogos & derivados , Oligopeptídeos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Compostos Radiofarmacêuticos/farmacocinética , Distribuição Tecidual
15.
Eur J Nucl Med Mol Imaging ; 49(11): 3910-3916, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35482114

RESUMO

PURPOSE: Uncertain focal bone uptake (UBU) with intensive radiopharmaceutical avidity are frequently observed in patients undergoing [18F]PSMA-1007 PET/CT for the detection of prostate cancer (PC). Such foci can pose diagnostic conundrums and risk incorrect staging. The aim of this short communication is to share the results of PET-guided biopsies of such foci. METHODS: A retrospective analysis revealed 10 patients who were referred to our department for PET-guided biopsy of UBU visible in a previous [18F]PSMA-1007 PET/CT. [18F]-PSMA-1007 PET-guided biopsy was conducted for 11 PSMA-avid bone foci in these 10 patients. The biopsy materials were analysed for tissue typing, and immunohistochemistry (IHC) was performed for prostate-specific-membrane-antigen (PSMA) expression. The scans were analysed by two experienced physicians in a consensus read for clinical characteristics and radiopharmaceutical uptake of foci. RESULTS: One out of 11 (9.1%) of the foci biopsied was confirmed as bone metastasis of PC with intense PSMA-expression, while 10/11 (90.9%) foci were revealed to be unremarkable bone tissue without evidence of PSMA expression at IHC. Amongst all bone foci assessed by biopsy, eight were visually classified as being at high risk of malignancy in the PET/CT (SUVmean 12.0 ± 8.1; SUVmax 18.8 ± 13.1), three as equivocal (SUVmean 4.6 ± 2.1; SUVmax 7.2 ± 3.0) and zero as low risk. No UBU had any CT correlate. CONCLUSIONS: This cohort biopsy revealed that a small but relevant number of UBU are true metastases. For those confirmed as benign, no PSMA expression at IHC was observed, suggesting a non-PSMA mediated cause for intensive [18F]PSMA-1007 uptake of which the reason remains unclear. Readers must interpret such foci with caution in order to reduce the risk of erroneous staging and subsequent treatment. PET-guided biopsy, particularly in the absence of morphological changes in the CT, can be a useful method to clarify such foci.


Assuntos
Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias da Próstata , Biópsia , Osso e Ossos/metabolismo , Radioisótopos de Gálio , Humanos , Masculino , Niacinamida/análogos & derivados , Oligopeptídeos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Neoplasias da Próstata/patologia , Compostos Radiofarmacêuticos , Estudos Retrospectivos
16.
J Pept Sci ; 28(2): e3366, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34463002

RESUMO

Structurally unique polyamidoamine (PAMAM) dendrimers implanted with targeting biological moiety along with complexed radiometal constitute a favorable nano-system for diagnosis and therapy of targeted tumor sites. In the present study, carboxyl functionalities of PAMAM- generation 4 dendrimer (PAMAM-G4-COOH) were conjugated with ε-amino group of lysine of cRGDfK peptide to impart integrin αv ß3 targeting capability. Reaction of p-NH2 -Bn-DOTA with PAMAM was accomplished via acid-amine coupling using EDC/NHS for 177 Lu-complexation. 177 Lu-labeled nano-system, 177 Lu-PAMAM-DOTA-cRGDfK demonstrated receptor-mediated uptake in murine melanoma B16F10 cells during in vitro cell uptake studies. In vivo biodistribution studies demonstrated low tumor uptake and retention of 177 Lu-PAMAM-DOTA-cRGDfK which may be attributed to rapid blood clearance. However, fast clearance from non-target organs resulted in higher target to background ratio. Tumor uptake of targeted nano-system, 177 Lu-PAMAM-DOTA-cRGDfK was observed to be significantly (p < 0.05) higher in comparison to 177 Lu-PAMAM-DOTA without the targeting peptide. Inhibition studies with unlabeled cRGDfK resulted in 60% reduction in tumor uptake of 177 Lu-PAMAM-DOTA-cRGDfK, indicating specificity of the developed nano-system towards integrin αv ß3 receptors.


Assuntos
Dendrímeros , Animais , Camundongos , Oligopeptídeos/metabolismo , Poliaminas , Distribuição Tecidual
17.
Eur J Nucl Med Mol Imaging ; 49(12): 4252-4261, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34773473

RESUMO

PURPOSE: Amongst others, [68Ga]Ga-PSMA-11 and [18F]PSMA-1007 are available for the detection of recurrent prostate cancer (rPC). There are currently limited data comparing the performance of these two radioligands with respect to clinical outcomes or their cost efficacy, which this study aims to address. METHODS: Two hundred and forty-four patients undergoing PSMA PET/CT for rPC were retrospectively analysed for this study (one hundred and twenty two with each radiopharmaceutical) to generate rates of PET positivity, negativity and unclear findings. Patients underwent follow-up to determine the rate of additional examinations and to confirm PET findings. A Markov chain decision analysis was implemented to model clinical decision-making processes and to analyse clinical performance of the two tracers. We determine their clinical cost efficacies using cost data from several countries where both radiotracers are in routine use. RESULTS: The PET positivity rate was non-significantly higher for [18F]PSMA-1007 compared to [68Ga]Ga-PSMA-11 (91.8% vs. 86.9%, p = 0.68), whereas the rate of uncertain findings was significantly greater (17.2% vs. 8.25%, p = 0.02). The probability of a true positive finding was higher for [68Ga]Ga-PSMA-11 (0.90, 95% CI 0.70-0.98) vs. [18F]PSMA-1007 (0.81, 95% CI 0.66-0.91). A significantly (p < 0.0001) higher PPV for [68Ga]Ga-PSMA-11 (0.99, 95% CI 0.99-1.0 vs. 0.86) was found compared to [18F]PSMA-1007 (0.86, 95% CI 0.82-1.00). Intervention efficacy analysis favoured [68Ga]Ga-PSMA-11, where the number needed to image (to achieve a true positive finding) was 10.58 and the number needed to image to harm (to achieve a false positive finding) was - 8.08. A cost efficacy analysis favours [68Ga]Ga-PSMA-11 in three of the four jurisdictions analysed where health economic data was available (Switzerland, Israel, Australia) and [18F]PSMA-1007 in one jurisdiction (Denmark). CONCLUSION: The analysis reveals a non-significantly higher PET positivity rate for [18F]PSMA-1007, but finds significantly greater rates of uncertain findings and false positive findings when compared to [68Ga]Ga-PSMA-11. We find differences in the two tracers in terms of clinical performance and cost efficacy. The method presented herein is generalisable and can be used with clinical or cost data for other countries or tracers.


Assuntos
Radioisótopos de Gálio , Neoplasias da Próstata , Técnicas de Apoio para a Decisão , Ácido Edético , Radioisótopos de Flúor , Isótopos de Gálio , Humanos , Masculino , Cadeias de Markov , Recidiva Local de Neoplasia/diagnóstico por imagem , Niacinamida/análogos & derivados , Oligopeptídeos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Neoplasias da Próstata/diagnóstico por imagem , Compostos Radiofarmacêuticos , Estudos Retrospectivos
18.
Nucl Med Commun ; 43(3): 332-339, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34954764

RESUMO

OBJECTIVE: The aim of the study was to evaluate the 18F-PSMA-1007 PET/computed tomography (CT) semiautomatic volumetric parameters to assess the whole-body tumor burden and its correlation with prostate-specific antigen (PSA) and Gleason score in patients with biochemically recurrent prostate cancer (PCa). MATERIALS AND METHODS: A total of 110 patients referred for 18F-PSMA-1007 PET/CT due to biochemical recurrence were retrospectively analyzed. Whole-body total lesion prostate-specific membrane antigen (wbTl-PSMA) and whole-body PSMA-derived tumor volume (wbPSMA-TV) metrics on 18F-PSMA-1007 were obtained semiautomatically in dedicated software. A Spearman test was performed to explore the correlation of volumetric imaging parameters with PSA levels and Gleason score. To analyze the association between volumetric measures and PSA subgroups, we used a Kruskal-Wallis test and a Dunn's test to identify each group causing an observed difference. RESULTS: A total of 492 metastatic lesions were analyzed, and a significant correlation was found between wbTL-PSMA (R = 0.63, P < 0.0001) and wbPSMA-TV (R = 0.49, P < 0.0001) with serum PSA. A statistically significant difference with wbTL-PSMA was found in patients with a PSA less than or equal 0.5 ng/ml and PSA in the range of 0.51-1.0 ng/ml. CONCLUSION: 18F-PSMA-1007 PSMA volumetric parameters can provide a quantitative imaging biomarker for whole-body tumor burden.


Assuntos
Niacinamida/análogos & derivados , Oligopeptídeos
19.
Sci Rep ; 11(1): 18311, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34526585

RESUMO

The adipokinetic hormone (AKH) of insects is considered an equivalent of the mammalian hormone glucagon as it induces fast mobilization of carbohydrates and lipids from the fat body upon starvation. Yet, in foraging honey bees, which lack fat body storage for carbohydrates, it was suggested that AKH may have lost its original function. Here we manipulated the energy budget of bee foragers to determine the effect of AKH on appetitive responses. As AKH participates in a cascade leading to acceptance of unpalatable substances in starved Drosophila, we also assessed its effect on foragers presented with sucrose solution spiked with salicin. Starved and partially-fed bees were topically exposed with different doses of AKH to determine if this hormone modifies food ingestion and sucrose responsiveness. We found a significant effect of the energy budget (i.e. starved vs. partially-fed) on the decision to ingest or respond to both pure sucrose solution and sucrose solution spiked with salicin, but no effect of AKH per se. These results are consistent with a loss of function of AKH in honey bee foragers, in accordance with a social life that implies storing energy resources in the hive, in amounts that exceed individual needs.


Assuntos
Abelhas/fisiologia , Metabolismo Energético , Comportamento Alimentar , Hormônios de Inseto/metabolismo , Oligopeptídeos/metabolismo , Ácido Pirrolidonocarboxílico/análogos & derivados , Animais , Abelhas/efeitos dos fármacos , Comportamento Animal , Metabolismo Energético/efeitos dos fármacos , Hormônios de Inseto/farmacologia , Oligopeptídeos/farmacologia , Ácido Pirrolidonocarboxílico/metabolismo , Ácido Pirrolidonocarboxílico/farmacologia , Inanição
20.
Artigo em Inglês | MEDLINE | ID: mdl-34285714

RESUMO

INTRODUCTION: Pulmonary fibrosis (PF) is characterized by an accelerated decline in pulmonary function and has limited treatment options. Alamandine (ALA) is a recently described protective peptide of the renin-angiotensin system (RAS) with essential tasks in several conditions. Our group previously demonstrated that ALA is reduced by 365% in the plasma of patients with idiopathic PF, and thus, it is plausible to believe that stimulation of this peptide could represent an important therapeutic target. In this sense, this study investigates the effects of ALA in an experimental model of PF. MATERIALS AND METHODS: Bleomycin (BLM) was administrated in Wistar rats, and these fibrotic animals were treated with ALA for 14 days. Body weight, histology, respiratory, and hemodynamic parameters were analyzed to study the effects of ALA. RESULTS: ALA treatment attenuated the development of fibrosis (P < 0.0001), reduced respiratory system elastance (P < 0.0001), and preserved weight gain (P < 0.0001) in fibrotic animals without affecting the autonomic control of blood pressure and heart rate. CONCLUSION: The data from this study demonstrate the potential of ALA to alleviate pulmonary fibrosis and improve respiratory system mechanics in vivo. The promising results encourage more detailed investigations of the potential of ALA as a future and efficient antifibrotic.


Assuntos
Fibrose Pulmonar , Animais , Humanos , Pulmão , Oligopeptídeos , Fibrose Pulmonar/tratamento farmacológico , Ratos , Ratos Wistar , Mecânica Respiratória , Roedores
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