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1.
Biomaterials ; 308: 122567, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38603825

RESUMO

Frequent injections of anti-CD124 monoclonal antibody (αCD124) over long periods of time are used to treat chronic rhinosinusitis with nasal polyps (CRSwNP). Needle-free, intranasal administration (i.n.) of αCD124 is expected to provide advantages of localized delivery, improved efficacy, and enhanced medication adherence. However, delivery barriers such as the mucus and epithelium in the nasal tissue impede penetration of αCD124. Herein, two novel protamine nanoconstructs: allyl glycidyl ether conjugated protamine (Nano-P) and polyamidoamine-linked protamine (Dendri-P) were synthesized and showed enhanced αCD124 penetration through multiple epithelial layers compared to protamine in mice. αCD124 was mixed with Nano-P or Dendri-P and then intranasally delivered for the treatment of severe CRSwNP in mice. Micro-CT and pathological changes in nasal turbinates showed that these two nano-formulations achieved ∼50 % and ∼40 % reductions in nasal polypoid lesions and eosinophil count, respectively. Both nano-formulations provided enhanced efficacy in suppressing nasal and systemic Immunoglobulin E (IgE) and nasal type 2 inflammatory biomarkers, such as interleukin 13 (IL-13) and IL-25. These effects were superior to those in the protamine formulation group and subcutaneous (s.c.) αCD124 given at a 12.5-fold higher dose. Intranasal delivery of protamine, Nano-P, or Dendri-P did not induce any measurable toxicities in mice.


Assuntos
Anticorpos Monoclonais , Pólipos Nasais , Protaminas , Rinossinusite , Animais , Feminino , Camundongos , Administração Intranasal , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/farmacologia , Doença Crônica , Camundongos Endogâmicos BALB C , Pólipos Nasais/tratamento farmacológico , Pólipos Nasais/patologia , Protaminas/química , Rinossinusite/tratamento farmacológico
2.
J Control Release ; 369: 199-214, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38537717

RESUMO

We found that immunosuppressive monocytic-myeloid-derived suppressor cells (M-MDSCs) were more likely to be recruited by glioblastoma (GBM) through adhesion molecules on GBM-associated endothelial cells upregulated post-chemoradiotherapy. These cells are continuously generated during tumor progression, entering tumors and expressing PD-L1 at a high level, allowing GBM to exhaust T cells and evade attack from the immune system, thereby facilitating GBM relapse. αLy-6C-LAMP is composed of (i) drug cores with slightly negative charges condensed by cationic protamine and plasmids encoding PD-L1 trap protein, (ii) pre-formulated cationic liposomes targeted to Ly-6C for encapsulating the drug cores, and (iii) a layer of red blood cell membrane on the surface for effectuating long-circulation. αLy-6C-LAMP persistently targets peripheral, especially splenic, M-MDSCs and delivers secretory PD-L1 trap plasmids, leveraging M-MDSCs to transport the plasmids crossing the blood-brain barrier (BBB), thus expressing PD-L1 trap protein in tumors to inhibit PD-1/PD-L1 pathway. Our proposed drug delivery strategy involving intermediaries presents an efficient cross-BBB drug delivery concept that incorporates live-cell targeting and long-circulating nanotechnology to address GBM recurrence.


Assuntos
Antígeno B7-H1 , Barreira Hematoencefálica , Neoplasias Encefálicas , Sistemas de Liberação de Medicamentos , Glioblastoma , Células Supressoras Mieloides , Recidiva Local de Neoplasia , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Animais , Barreira Hematoencefálica/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Humanos , Células Supressoras Mieloides/efeitos dos fármacos , Linhagem Celular Tumoral , Recidiva Local de Neoplasia/prevenção & controle , Lipossomos , Camundongos Endogâmicos C57BL , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Protaminas/química , Protaminas/administração & dosagem , Camundongos , Monócitos/efeitos dos fármacos , Monócitos/metabolismo
3.
J Control Release ; 368: 290-302, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38423473

RESUMO

Therapeutic proteins often require needle-based injections, which compromise medication adherence especially for those with chronic diseases. Sublingual administration provides a simple and non-invasive alternative. Herein, two novel peptides (lipid-conjugated protamine and a protamine dimer) were synthesized to enable sublingual delivery of proteins through simple physical mixing with the payloads. It was found that the novel peptides promoted intracellular delivery of proteins via increased pore formation on the cell surface. Results from in vitro models of cell spheroids and human sublingual tissue substitute indicated that the novel peptides enhanced protein penetration through multiple cell layers compared to protamine. The novel peptides were mixed with insulin or semaglutide and sublingually delivered to mice for blood glucose (BG) control. The effects of these sublingual formulations were comparable to the subcutaneous preparations and superior to protamine. In addition to peptide drugs, the novel peptides were shown to enable sublingual absorption of larger proteins with molecular weights from 22 to 150 kDa in mice, including human recombinant growth hormone (rhGH), bovine serum albumin (BSA) and Immunoglobulin G (IgG). The novel peptides given sublingually did not induce any measurable toxicities in mice.


Assuntos
Imunoglobulina G , Peptídeos , Animais , Camundongos , Humanos , Administração Sublingual , Protaminas
4.
Transfusion ; 64(3): 467-474, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38264767

RESUMO

BACKGROUND: Bleeding after cardiac surgery is common and continues to require 10-20% of the national blood supply. Transfusion of allogeneic blood is associated with increased morbidity and mortality. Excessive protamine in the absence of circulating heparin after weaning off CPB can cause anticoagulation and precipitate bleeding. Hence, adequate dose calculation of protamine is crucial yet under evaluated. STUDY DESIGN: Retrospective cohort study. METHODS: We conducted a retrospective bi-institutional analysis of cardiac surgical patients who underwent cardiopulmonary bypass (CPB)-assisted cardiac surgery to assess the impact of protamine dosing in transfusion practice. Total 762 patients were identified from two institutions using electronic medical records and the Society of Thoracic Surgery (STS) database who underwent cardiac surgery using CPB. Patients were similar in demographics and other baseline characteristics. We divided patients into two groups based on mg of protamine administered to neutralize each 100 U of unfractionated heparin (UFH)-low-ratio group (Protamine: UFH ≤ 0.8) and high-ratio group (Protamine: UFH > 0.8). RESULTS: We observed a higher rate of blood transfusion required in high-ratio group (ratio >0.8) compared with low-ratio group (ratio ≤0.8) (p < .001). The increased requirement was consistently demonstrated for intraoperative transfusions of red blood cells, plasma, platelets, and cryoprecipitate. CONCLUSION: High protamine to heparin ratio may cause increased bleeding and transfusion in cardiac surgical patients. Protamine to heparin ratio of 0.8 or lower is sufficient to neutralize circulating heparin after weaning off cardiopulmonary bypass.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Cirurgia Torácica , Humanos , Heparina , Protaminas/uso terapêutico , Estudos Retrospectivos , Transfusão de Sangue , Ponte Cardiopulmonar , Anticoagulantes/uso terapêutico , Antagonistas de Heparina
7.
Can J Anaesth ; 71(2): 234-243, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37985627

RESUMO

PURPOSE: It has been suggested that a larger heparin dose during cardiopulmonary bypass (CPB) is associated with reduced perioperative coagulopathy and thromboembolic complications. We investigated the effect of different heparin doses during routine elective cardiac surgery. Our primary outcomes include blood loss and transfusion and secondary outcomes investigate the effects on coagulation biomarkers. METHODS: In this prospective pilot trial, we allocated 60 patients undergoing cardiac surgery on CPB in a single tertiary cardiac centre into three groups to receive an initial dose of 300, 400, or 500 units (U) per kilogram of intravenous heparin prior to the commencement of CPB. Blood was sampled after induction of anesthesia, at 30 and 60 min of CPB, and three minutes after heparin reversal with protamine. Samples were analyzed for fibrinopeptide A (FPA), fibrinopeptide B (FPB), D-dimer, and thrombin-antithrombin (TAT) complexes. Postoperative blood loss and transfusion was measured for the first 24-hr period after surgery. RESULTS: The total mean (95% CI) administered heparin dose in the 300 U·kg-1, 400 U·kg-1, and 500 U·kg-1 groups were 39,975 (36,528 to 43,421) U, 43,195 (36,940 to 49,449) U and 47,900 (44,807 to 50,992) U, respectively. There were no statistically significant differences in FPA, FPB or D-dimer levels at the measured time intervals. There was a trend towards lower TAT levels while on CPB with greater heparin dosing, which was statistically significant after the administration of protamine. The clinical significance appears to be negligible, as there is no difference in overall blood loss and amount of packed red blood cell transfusion or other blood product transfusion. CONCLUSION: This pilot study indicates that, while larger heparin dosing for routine cardiac surgery results in subtle biochemical changes in coagulation, there is no demonstrable benefit in postoperative blood loss or transfusion requirements.


RéSUMé: OBJECTIF: Il a été suggéré qu'une dose plus élevée d'héparine pendant la circulation extracorporelle (CEC) serait associée à une réduction de la coagulopathie périopératoire et des complications thromboemboliques. Nous avons étudié l'effet de différentes doses d'héparine au cours d'une chirurgie cardiaque non urgente de routine. Nos critères d'évaluation principaux comprenaient la perte de sang et la transfusion, et les critères d'évaluation secondaires exploraient les effets sur les biomarqueurs de la coagulation. MéTHODE: Dans cette étude pilote prospective, nous avons réparti 60 patient·es bénéficiant d'une chirurgie cardiaque sous CEC dans un seul centre cardiaque tertiaire en trois groupes à recevoir une dose initiale de 300, 400 ou 500 unités (U) par kilogramme d'héparine intraveineuse avant le début de la CEC. Le sang a été prélevé après l'induction de l'anesthésie, à 30 et 60 minutes de CEC, et trois minutes après la neutralisation de l'héparine avec la protamine. Les échantillons ont été analysés pour les complexes fibrinopeptide A (FPA), fibrinopeptide B (FPB), D-dimère et thrombine-antithrombine (TAT). La perte de sang postopératoire et la transfusion ont été mesurées pendant la première période de 24 heures après la chirurgie. RéSULTATS: La dose moyenne totale (IC 95 %) d'héparine administrée dans les 300 U·kg−1, 400 U·kg−1, et 500 U·kg−1 était de 39 975 (36 528 à 43 421) U, 43 195 (36 940 à 49 449) U et 47 900 (44 807 à 50 992) U, respectivement. Il n'y avait aucune différence statistiquement significative dans les taux de FPA, FPB ou D-dimères aux intervalles de temps mesurés. Une tendance à des niveaux de TAT plus bas pendant la CEC a été observée avec une dose d'héparine plus élevée, ce qui était statistiquement significatif après l'administration de protamine. La signification clinique semble négligeable, car il n'y a pas de différence dans la perte de sang globale et la quantité de transfusion de concentrés globulaires ou d'autres produits sanguins. CONCLUSION: Cette étude pilote indique que, bien qu'une dose plus importante d'héparine pour la chirurgie cardiaque de routine entraîne des changements biochimiques subtils dans la coagulation, il n'y a aucun avantage démontrable en matière de saignement postopératoire ou de besoins transfusionnels.


Assuntos
Ponte Cardiopulmonar , Heparina , Humanos , Projetos Piloto , Estudos Prospectivos , Perda Sanguínea Cirúrgica , Hemorragia Pós-Operatória/tratamento farmacológico , Anticoagulantes , Protaminas
8.
Perfusion ; 39(4): 784-789, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38124316

RESUMO

OBJECTIVES: In our center, an unusual rate of patients had abnormalities of hemostasis in immediate postoperative period of cardiac surgery. Our objectives were to identify the cause of these sudden hemostasis abnormalities and to evaluate the performances of point of care coagulation testing. METHODS: In this prospective and descriptive study, we included 33 consecutive patients undergoing elective cardiac surgery for 1 month. Heparin-induced anticoagulation and calculation of the protamine dose were tested by the Hemostasis Management System Plus device (Medtronic, Minneapolis, MN, USA). Fifteen minutes after the end of the protamine infusion, activated clotting time (ACT), activated partial thromboplastin time and anti Xa activity were measured. In case of unusual clinical bleeding, a Quantra analysis (Stago, HemoSonics LLC, Charlottesville, VA) was added. RESULTS: Residual antiXa activity >0.2 IU/mL after neutralization was present in 44% of patients. Our investigation concluded incomplete heparin reversal. There was no association between cellular reinfusate and the presence of heparin. The unusual rate of hemostasis abnormalities was explained by a less efficient protamine reversal of heparin. ACT and Clot Time Ratio (CTR, Quantra system) correlated with AntiXa with Spearman's coefficients of 0.85 (p < .0001) and 0.95 (p = .0012), respectively. About ACT, a threshold of 150 seconds had a sensitivity of 85% [58-97] and a specificity of 85% [58-97%] for detection of AntiXa>0.2. For CTR, a threshold of 1.4 had a sensitivity of 67% [30-94] and a specificity of 100% [18-100]. CONCLUSION: The use of point of care coagulation testing is effective in detecting incomplete reversal of heparin.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Heparina , Humanos , Heparina/efeitos adversos , Heparina/uso terapêutico , Masculino , Feminino , Procedimentos Cirúrgicos Cardíacos/métodos , Idoso , Estudos Prospectivos , Pessoa de Meia-Idade , Protaminas/uso terapêutico , Anticoagulantes/uso terapêutico , Anticoagulantes/farmacologia , Testes de Coagulação Sanguínea/métodos
9.
Phys Chem Chem Phys ; 25(45): 31335-31345, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37960891

RESUMO

Protamines, arginine-rich DNA-binding proteins, are responsible for chromatin compaction in sperm cells, but their DNA groove preference, major or minor, is not clearly identified. We herein study the DNA groove preference of a short protamine-like cationic peptide before and after phosphorylation, using all-atom molecular dynamics and umbrella sampling simulations. According to various thermodynamic and structural analyses, a peptide in its non-phosphorylated native state prefers the minor groove over the major groove, but phosphorylation of the peptide bound to the minor groove not only reduces its binding affinity but also brings a serious deformation of the minor groove, eliminating the minor-groove preference. As protamines are heavily phosphorylated before binding to DNA, we expect that the structurally disordered phosphorylated protamines would prefer major grooves to enter into DNA during spermatogenesis.


Assuntos
Protaminas , Sêmen , Masculino , Humanos , Protaminas/química , Protaminas/metabolismo , Fosforilação , Sêmen/metabolismo , DNA/química , Peptídeos/química , Espermatozoides/metabolismo , Cátions/metabolismo
10.
Biophys J ; 122(21): 4288-4302, 2023 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-37803830

RESUMO

DNA in sperm undergoes an extreme compaction to almost crystalline packing levels. To produce this dense packing, DNA is dramatically reorganized in minutes by protamine proteins. Protamines are positively charged proteins that coat negatively charged DNA and fold it into a series of toroids. The exact mechanism for forming these ∼50-kbp toroids is unknown. Our goal is to study toroid formation by starting at the "bottom" with folding of short lengths of DNA that form loops and working "up" to more folded structures that occur on longer length scales. We previously measured folding of 200-300 bp of DNA into a loop. Here, we look at folding of intermediate DNA lengths (L = 639-3003 bp) that are 2-10 loops long. We observe two folded structures besides loops that we hypothesize are early intermediates in the toroid formation pathway. At low protamine concentrations (∼0.2 µM), we see that the DNA folds into flowers (structures with multiple loops that are positioned so they look like the petals of a flower). Folding at these concentrations condenses the DNA to 25% of its original length, takes seconds, and is made up of many small bending steps. At higher protamine concentrations (≥2 µM), we observe a second folded structure-the loop stack-where loops are stacked vertically one on top of another. These results lead us to propose a two-step process for folding at this length scale: 1) protamine binds to DNA, bending it into loops and flowers, and 2) flowers collapse into loop stacks. These results highlight how protamine uses a bind-and-bend mechanism to rapidly fold DNA, which may be why protamine can fold the entire sperm genome in minutes.


Assuntos
Protaminas , Sementes , Protaminas/química , Protaminas/metabolismo , Sementes/metabolismo , DNA/química , Espermatozoides/metabolismo , Flores/metabolismo
11.
Int J Pharm ; 646: 123474, 2023 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-37793466

RESUMO

AIM: The current study aimed to develop enzyme-activated charge-reversal lipid nanoparticles (LNPs) as novel gene delivery systems. METHODS: Palmitic acid was covalently bound to protamine being utilised as transfection promoter to anchor it on the surfaces of LNPs. Green fluorescent protein (GFP) encoding plasmid DNA (pDNA) was ion paired with various cationic counter ions to achieve high encapsulation in LNPs. Protamine-decorated LNPs were prepared by solvent injection method followed by coating with sodium tripolyphosphate (TPP) to generate a bio-inert anionic outer surface. Resulting LNPs were characterised regarding size, polydispersity, zeta potential and encapsulation efficiency. Enzyme-triggered charge-reversal of LNPs was investigated using isolated alkaline phosphatase (ALP) monitoring changes in zeta potential as well as monophosphate release. Furthermore, monophosphate release, cell viability and transfection efficiency were evaluated on a human alveolar epithelial (A549) cell line. RESULTS: Protamine-decorated and TPP-coated (Prot-pDNA/DcChol-TPP) LNPs displayed a mean size of 298.8 ± 17.4 nm and a zeta potential of -13.70 ± 0.61 mV. High pDNA encapsulation was achieved with hydrophobic ion pairs of pDNA with 3ß-[N-(N',N'-dimethylaminoethane)-carbamoyl]cholesterol hydrochloride (DcChol). Zeta potential of Prot-pDNA/DcChol-TPP LNPs reversed to positive values with a total Δ26.8 mV shift upon incubation with ALP. Conformably, a notable amount of monophosphate was released upon incubation of Prot-pDNA/DcChol-TPP LNPs with isolated as well as cell-associated ALP. A549 cells well tolerated LNPs displaying more than 95 % viability. Compared with naked pDNA, unmodified LNPs and control LNPs, Prot-pDNA/DcChol-TPP LNPs showed a significantly increased transfection efficiency. CONCLUSION: Prot-pDNA/DcChol-TPP LNPs can be regarded as promising gene delivery systems.


Assuntos
Técnicas de Transferência de Genes , Nanopartículas , Humanos , Plasmídeos , Transfecção , DNA , Nanopartículas/química , Protaminas
12.
J Extra Corpor Technol ; 55(3): 105-111, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37682208

RESUMO

BACKGROUND: Systemic anticoagulation with heparin during cardiopulmonary bypass (CPB) should be neutralized by protamine administration to restore normal hemostasis. Our previous study showed the protamine-to-heparin ratio (P-to-H) of 1:1 (1 mg protamine:100 IU circulating heparin; 1.0 Ratio) is likely an overestimation. Thus, we reduced the P-to-H in the HMS Plus Hemostasis Management System to 0.9:1 (0.9 Ratio) for 5 months and then to 0.8:1 (0.8 Ratio). We monitored post-operative (post-op) bleeding in the setting of reduced protamine dose (PD). METHODS: We performed a retrospective study of 632 patients (209 for the 1.0 Ratio, 211 for 0.9 Ratio, 212 for 0.8 Ratio group) who underwent cardiac surgery to measure the reduction of PD and how it affects 24-hour (24 h) post-op chest tube output. We also analyzed the entire data set to explore whether further reduction of P-to-H is warranted. RESULTS: While there was no difference in the indexed heparin dose among the three groups, we achieved a significant reduction in the indexed actual protamine dose (APDi) by 24% (0.9 Ratio) and 31% (0.8 Ratio) reductions compared to the 1.0 Ratio group. On average, APDi was 88 ± 22, 67 ± 18, and 61 ± 15 mg/m2 in the 1.0, 0.9, and 0.8 Ratio groups, respectively. We found no significant difference in 24 h post-op bleeding among the three groups. CONCLUSION: 1.0 Ratio at the completion of CPB is likely an excessive administration of protamine. With the stepwise reduction of PD, we observed no increase in post-op bleeding, which may indicate that no meaningful increase in heparin rebound occurred. In addition, further analysis of the entire data set demonstrates that a 0.75 Ratio is likely sufficient to neutralize the heparin completely.


Assuntos
Ponte Cardiopulmonar , Heparina , Humanos , Ponte Cardiopulmonar/efeitos adversos , Heparina/efeitos adversos , Estudos Retrospectivos , Hemorragia Pós-Operatória/etiologia , Hemorragia Pós-Operatória/prevenção & controle , Protaminas
13.
Biomater Sci ; 11(16): 5533-5539, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37395046

RESUMO

Heparin is a widely used anticoagulant agent in the clinic. After application, its anticoagulant effect must be reversed to prevent potential side effects. Protamine sulfate (PS) is the only clinically licensed antidote that has been used for this purpose in the last 80 years, which, however, provokes severe adverse effects, such as systemic hypotension and even death. Herein, we demonstrate the potential of supercharged polypeptides as a promising alternative for protamine sulfate. A series of supercharged polypeptides with multiple positive charges was recombinantly produced, and the heparin-neutralizing performance of the polypeptides was evaluated in comparison with PS. It was found that increasing the number of charges significantly enhanced the ability to neutralize heparin and resist the screening effect induced by salt. In particular, the polypeptide bearing 72 charges (K72) exhibited an excellent heparin-neutralizing behavior that was comparable to that of PS. Further in vivo studies revealed that the heparin-triggered bleeding was almost completely alleviated by K72 while a negligible toxic effect was observed. Therefore, such recombinant supercharged polypeptides might replace protamine sulfate as heparin-reversal agents.


Assuntos
Anticoagulantes , Heparina , Humanos , Heparina/farmacologia , Anticoagulantes/farmacologia , Protaminas/efeitos adversos , Peptídeos/uso terapêutico , Hemorragia/induzido quimicamente , Hemorragia/tratamento farmacológico
14.
J Mater Chem B ; 11(31): 7389-7400, 2023 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-37431691

RESUMO

Inhibiting the formation of urate crystals is the key to prevent hyperuricemia from developing into gout. Although many studies have focused on the influence of biomacromolecules in the crystallization behavior of sodium urate, the role of peptides with specific structures may contribute to unprecedented regulatory effects. Here, for the first time, we studied the effects of cationic peptides on the phase behavior, crystallization kinetics, and size/morphology of urate crystals. The addition of protamine (PRTM, a typical natural arginine-rich peptide) prolongs the nucleation induction time of sodium urate and inhibits crystal nucleation effectively. PRTM binds to the surface of amorphous sodium urate (ASU) through the hydrogen bond and electrostatic attraction between guanidine groups and urate anions, which is conducive to maintaining the state of ASU and inhibiting crystal nucleation. Moreover, PRTM preferentially binds to the MSUM plane and leads to a significant reduction in the aspect ratio of MSUM filamentous crystals. Further studies showed that there are significant differences in the inhibiting effects of arginine-rich peptides with different chain lengths on the crystallization behavior of sodium urate. Both guanidine functional groups and peptide chain length determine the crystallization inhibiting effect of peptides simultaneously. The present work highlights the potential role of arginine peptides in inhibiting the crystallization of urate and provides new insights into the inhibition mechanism in the pathological biomineralization of sodium urate, demonstrating the possibility of using cationic peptides to treat gout.


Assuntos
Peptídeos , Protaminas/química , Protaminas/metabolismo , Animais , Peptídeos/química , Salmão , Cristalização , Tamanho da Partícula
15.
Cancer Imaging ; 23(1): 68, 2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37452405

RESUMO

PURPOSE: Percutaneous hepatic perfusion (PHP) is a palliative intraarterial therapy for unresectable hepatic malignancies. During PHP, high-dose melphalan is infused via the hepatic artery to saturate tumor in the liver with the chemotherapeutic substance. The venous hepatic blood is filtered by an extracorporeal melphalan specific filtration system. Blood clotting in the extracorporeal filter system is prevented by administering unfractionated heparin (UFH) in high doses, which might be reversed with protamine sulfate after the procedure. Aim of this retrospective two-center-study was to analyze the potential effect of UFH reversal with protamine sulfate on complication rates following PHP. MATERIALS AND METHODS: All patients receiving PHP treatment between 10/2014 and 04/2021 were classified according to their intraprocedural coagulation management: 92 patients/192 PHP received full UFH reversal with protamine (groupPROTAMINE); 13 patients/21 PHP in groupREDUCED_PROTAMINE received a reduced amount of protamine, and 28 patients/43 PHP did not receive UFH reversal with protamine (groupNO_PROTAMINE). Periinterventional clinical reports, findings and laboratory values were retrospectively evaluated. Complications and adverse events were classified according to Common Terminology Criteria for Adverse Events (CTCAEv5.0). RESULTS: Thromboembolic events were recorded after 10 PHP procedures (5%) in groupPROTAMINE, six of which (3%) were major events (CTCAE grade 3-5). No (0%) thromboembolic events were recorded in groupREDUCED_PROTAMINE and groupNO_PROTAMINE. Hemorrhagic events were registered after 24 PHP (13%) in groupPROTAMINE, two of which (1%) were major (CTCAE grade 3-4). In groupREDUCED_PROTAMINE, only minor bleeding events were recorded, and one major hemorrhagic event was documented in groupNO_PROTAMINE (2%). There was a significant difference between the percentage of post-interventional thrombopenia in groupPROTAMINE (39%) and groupREDUCED_PROTAMINE (14%) versus groupNO_PROTAMINE (23%) (p=.00024). In groupPROTAMINE one patient suffered from a severe anaphylactic shock after the administration of protamine. CONCLUSION: Our retrospective study implies that there might be a link between the practice of protamine sulfate administration to reverse the full hemodilutive effect of UFH after PHP and the post-interventional risk of thromboembolic events as well as clinically significant thrombopenia. Our data suggest that the standard use of protamine sulfate after PHP in low-risk patients without clinical signs of active bleeding should be critically re-evaluated.


Assuntos
Heparina , Trombocitopenia , Humanos , Heparina/uso terapêutico , Melfalan , Estudos Retrospectivos , Protaminas/uso terapêutico , Trombocitopenia/induzido quimicamente , Trombocitopenia/tratamento farmacológico , Perfusão
16.
NMR Biomed ; 36(11): e5007, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37469121

RESUMO

Chemical exchange saturation transfer (CEST) MRI has been identified as a novel alternative to classical diagnostic imaging. Over the last several decades, many studies have been conducted to determine possible CEST agents, such as endogenously expressed compounds or proteins, that can be utilized to produce contrast with minimally invasive procedures and reduced or non-existent levels of toxicity. In recent years there has been an increased interest in the generation of genetically engineered CEST contrast agents, typically based on existing proteins with CEST contrast or modified to produce CEST contrast. We have developed an in silico method for the evolution of peptide sequences to optimize CEST contrast and showed that these peptides could be combined to create de novo biosensors for CEST MRI. A single protein, superCESTide, was designed to be 198 amino acids. SuperCESTide was expressed in E. coli and purified with size exclusion chromatography. The magnetic transfer ratio asymmetry generated by superCESTide was comparable to levels seen in previous CEST reporters, such as protamine sulfate (salmon protamine) and human protamine. These data show that novel peptides with sequences optimized in silico for CEST contrast that utilize a more comprehensive range of amino acids can still produce contrast when assembled into protein units expressed in complex living environments.


Assuntos
Técnicas Biossensoriais , Escherichia coli , Humanos , Imageamento por Ressonância Magnética/métodos , Peptídeos , Protaminas , Aminoácidos , Meios de Contraste/química
17.
Pain ; 164(12): 2653-2664, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37467181

RESUMO

ABSTRACT: We have previously shown that intradermal injection of high-molecular-weight hyaluronan (500-1200 kDa) produces localized antihyperalgesia in preclinical models of inflammatory and neuropathic pain. In the present experiments, we studied the therapeutic effect of topical hyaluronan, when combined with each of 3 transdermal drug delivery enhancers (dimethyl sulfoxide [DMSO], protamine or terpene), in preclinical models of inflammatory and neuropathic pain. Topical application of 500 to 1200 kDa hyaluronan (the molecular weight range used in our previous studies employing intradermal administration), dissolved in 75% DMSO in saline, markedly reduced prostaglandin E 2 (PGE 2 ) hyperalgesia, in male and female rats. Although topical 500- to 1200-kDa hyaluronan in DMSO vehicle dose dependently, also markedly, attenuated oxaliplatin chemotherapy-and paclitaxel chemotherapy-induced painful peripheral neuropathy (CIPN) in male rats, it lacked efficacy in female rats. However, following ovariectomy or intrathecal administration of an oligodeoxynucleotide antisense to G-protein-coupled estrogen receptor (GPR30) mRNA, CIPN in female rats was now attenuated by topical hyaluronan. Although topical coadministration of 150 to 300, 300 to 500, or 1500 to 1750 kDa hyaluronan with DMSO also attenuated CIPN, a slightly lower-molecular-weight hyaluronan (70-120 kDa) did not. The topical administration of a combination of hyaluronan with 2 other transdermal drug delivery enhancers, protamine and terpene, also attenuated CIPN hyperalgesia, an effect that was more prolonged than with DMSO vehicle. Repeated administration of topical hyaluronan prolonged the duration of antihyperalgesia. Our results support the use of topical hyaluronan, combined with chemically diverse nontoxic skin penetration enhancers, to induce marked antihyperalgesia in preclinical models of inflammatory and neuropathic pain.


Assuntos
Ácido Hialurônico , Neuralgia , Ratos , Masculino , Feminino , Animais , Ácido Hialurônico/uso terapêutico , Hiperalgesia/tratamento farmacológico , Hiperalgesia/induzido quimicamente , Ratos Sprague-Dawley , Dimetil Sulfóxido/efeitos adversos , Neuralgia/tratamento farmacológico , Neuralgia/induzido quimicamente , Paclitaxel/efeitos adversos , Protaminas/efeitos adversos
18.
J Cardiothorac Vasc Anesth ; 37(9): 1618-1623, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37302932

RESUMO

OBJECTIVE: To retrospectively evaluate a protamine conservation approach to heparin reversal implemented during times of critical shortages. This approach was aimed at maintaining access to cardiac surgical services. SETTING: In-patient hospital setting. PARTICIPANTS: Eight hundred-one cardiac surgical patients>18 years old. INTERVENTIONS: Patients undergoing cardiac surgery who received >30,000 U of heparin were given a single fixed vial protamine dose of 250 mg or a standard 1 mg of protamine to 100 U of heparin ratio-based dose to reverse heparin. MEASUREMENTS AND MAIN RESULTS: The primary endpoint was differences in post-reversal activated clotting times between the 2 groups. The secondary endpoint was differences in the number of protamine vials used between the 2 reversal strategies. The first activated clotting times values measured after initial protamine administration were not different between the Low Dose and Conventional Dose groups (122.3 s v 120.6 s, 1.47 s, 99% CI -1.47 to 4.94, p = 0.16). The total amount of protamine administered in the Low Dose group was less than that in the Conventional Dose group (-100.5 mg, 99% CI -110.0 to -91.0, p < 0.0001), as were the number of 250 mg vials used per case (-0.69, 99% CI -0.75 to -0.63, p < 0.0001). The mean initial protamine doses between groups were 250 mg and 352 mg, p < 0.0001. The mean protamine vials used were 1.33 v 2.02, p < 0.0001. When the calculations were based on 50 mg vials, the number of vials used per case in the Low Dose group was even less (-2.16, 99% CI -2.36 to -1.97, p < 0.0001).) CONCLUSIONS: Conservation measures regarding critical medications and supplies during times of shortages can maintain access to important services within a community.


Assuntos
Heparina , Protaminas , Humanos , Adolescente , Estudos Retrospectivos , Estudos de Coortes , Testes de Coagulação Sanguínea , Antagonistas de Heparina , Ponte Cardiopulmonar/métodos
19.
Vasc Endovascular Surg ; 57(8): 869-877, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37303024

RESUMO

INTRODUCTION: The purpose of this study is to investigate regional variation and temporal trends in seven quality metrics amongst CEA patients: discharge on antiplatelet after CEA; discharge on statin after CEA; protamine administration during CEA; patch placement at conventional CEA site; continued statin usage at the time of most recent follow-up; continued antiplatelet usage at the time of most recent follow-up; and smoking cessation at the time of long term follow up. METHODS: There are 19 de-identified regions within the VQI database in the United States. Patients were placed into one of three temporal eras based on the time of their CEA: 2003-2008; 2009-2015; and 2016-2022. We first investigated temporal trends across the seven quality metrics for all regions combined on a national basis. The percentage of patients in each time era with the presence/absence of each metric was identified. Chi-squared testing was performed to confirm statistical significance of the differences across eras. Next, analysis was performed within each region and within each time metric. We separated out the 2016-2022 patients within each region to serve as the status of each metric application in the most modern era. We then compared the frequency of metric non-adherence in each region utilizing Chi-squared testing. RESULTS: There was statistically significant improvement in achievement of all seven metrics between the initial 2003-2008 era and the modern 2016-2022 era. The most marked change in practice pattern was noted for lack of protamine usage at surgery (decreased from 48.7% to 25.9%), discharge home postoperatively without statin (decreased from 50.6% to 15.3%), and lack of statin usage confirmed at time of most recent long term follow up (decreased from 24% to 8.9%). Significant regional variation exists across all metrics (P < .01 for all). Lack of patch placement at the time of conventional endarterectomy ranges from 1.9% to 17.8% across regions in the modern era. Lack of protamine utilization ranges from 10.8% to 49.7%. Lack of antiplatelet and statin at the time of discharge varies from 5.5% to 8.2% and 4.8% to 14.4% respectively. Adherence to the various measures at the time of most recent follow up are more tightly aligned across regions with ranges of: 5.3% to 7.5% for lack of antiplatelet usage; 6.6% to 11.7% lack of statin utilization; and 13.3 to 15.4% for persistent smoking. CONCLUSIONS: Prior studies and societal initiatives on CEA documenting the beneficial effects of patch angioplasty, protamine use at surgery, smoking cessation, antiplatelet utilization and statin compliance have positively impacted adherence to these measures over time. In the modern 2016-2022 era the widest regional variation is noted in patch placement, protamine utilization and discharge medications allowing individual geographic areas to identify areas for potential improvement via internal VQI administrative feedback.


Assuntos
Estenose das Carótidas , Endarterectomia das Carótidas , Inibidores de Hidroximetilglutaril-CoA Redutases , Acidente Vascular Cerebral , Humanos , Estados Unidos/epidemiologia , Endarterectomia das Carótidas/efeitos adversos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Resultado do Tratamento , Angioplastia , Protaminas/efeitos adversos , Fatores de Risco , Estenose das Carótidas/cirurgia , Estudos Retrospectivos , Medição de Risco
20.
Inhal Toxicol ; 35(7-8): 175-184, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37145555

RESUMO

BACKGROUND: Waterpipe smoking is harmful and dangerous, and it is a growing threat to public health. OBJECTIVES: This study was performed to evaluate the influence of waterpipe smoking on global DNA methylation, DNA fragmentation, and protamine deficiency in spermatozoa compared to cigarette heavy smokers and nonsmokers, and to determine whether the transcription levels of spermatozoa nuclear proteins genes 'PRM1, PRM2, and H2BFWT' in waterpipe smokers are different compared to cigarette heavy smokers and nonsmokers. METHODS: A total of 900 semen samples were collected from males with a mean age of 32.5 ± 6.3 years (300 waterpipe smokers, 300 cigarette heavy smokers, and 300 nonsmokers). The nucleic acids were isolated from purified spermatozoa, and then the global DNA methylation and transcription levels of the PRM1, PRM2, and H2BFWT genes were assessed using ELISA and qPCR, respectively. RESULTS: A significant increase was found in the level of global DNA methylation (8.6 ± 0.6 ng/µl vs. 7.1 ± 0.6 ng/µl and 4.7 ± 0.6 ng/µl, p < 0.001), protamine deficiency (72.8 ± 15.3 vs. 51.7 ± 19.2 and 15.3 ± 5.9%, p < 0.001), and DNA fragmentation (73.4 ± 13.4 vs. 50.5 ± 18.9 and 9.3 ± 4.3%, p < 0.001) in waterpipe smokers compared to cigarette heavy smokers and nonsmokers. A significant increase was shown in the transcription levels of PRM1, PRM2, and H2BFWT genes in waterpipe smokers compared to cigarette heavy smokers and nonsmokers (p < 0.001). A down-regulation was found in the transcription level of these genes in different smoker groups compared to nonsmokers (<0.001). CONCLUSION: This study suggests that waterpipe smoking is more harmful than cigarette smoking on semen parameters, global DNA methylation, and transcription of nuclear protein genes.


Assuntos
Fumar Cigarros , Produtos do Tabaco , Fumar Cachimbo de Água , Metilação de DNA , Proteínas Nucleares , Protaminas/genética , Espermatozoides
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