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1.
ACS Omega ; 9(18): 19741-19755, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38737049

RESUMO

In recent years, the development of biomaterials from green organic sources with nontoxicity and hyposensitivity has been explored for a wide array of biotherapeutic applications. Polyphenolic compounds have unique structural features, and self-assembly by oxidative coupling allows molecular species to rearrange into complex biomaterial that can be used for multiple applications. Self-assembled polyphenolic structures, such as hollow spheres, can be designed to respond to various chemical and physical stimuli that can release therapeutic drugs smartly. The self-assembled metallic-phenol network (MPN) has been used for modulating interfacial properties and designing biomaterials, and there are several advantages and challenges associated with such biomaterials. This review comprehensively summarizes current challenges and prospects of self-assembled polyphenolic hollow spheres and MPN coatings and self-assembly for biomedical applications.

2.
J Vis Exp ; (206)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38738900

RESUMO

Bacterial cytoskeletal proteins such as FtsZ and MreB perform essential functions such as cell division and cell shape maintenance. Further, FtsZ and MreB have emerged as important targets for novel antimicrobial discovery. Several assays have been developed to identify compounds targeting nucleotide binding and polymerization of these cytoskeletal proteins, primarily focused on FtsZ. Moreover, many of the assays are either laborious or cost-intensive, and ascertaining whether these proteins are the cellular target of the drug often requires multiple methods. Finally, the toxicity of the drugs to eukaryotic cells also poses a problem. Here, we describe a single-step cell-based assay to discover novel molecules targeting bacterial cytoskeleton and minimize hits that might be potentially toxic to eukaryotic cells. Fission yeast is amenable to high-throughput screens based on microscopy, and a visual screen can easily identify any molecule that alters the polymerization of FtsZ or MreB. Our assay utilizes the standard 96-well plate and relies on the ability of the bacterial cytoskeletal proteins to polymerize in a eukaryotic cell such as the fission yeast. While the protocols described here are for fission yeast and utilize FtsZ from Staphylococcus aureus and MreB from Escherichia coli, they are easily adaptable to other bacterial cytoskeletal proteins that readily assemble into polymers in any eukaryotic expression hosts. The method described here should help facilitate further discovery of novel antimicrobials targeting bacterial cytoskeletal proteins.


Assuntos
Antibacterianos , Proteínas de Bactérias , Proteínas do Citoesqueleto , Schizosaccharomyces , Schizosaccharomyces/efeitos dos fármacos , Schizosaccharomyces/metabolismo , Proteínas do Citoesqueleto/metabolismo , Proteínas do Citoesqueleto/antagonistas & inibidores , Antibacterianos/farmacologia , Antibacterianos/química , Proteínas de Bactérias/metabolismo , Avaliação Pré-Clínica de Medicamentos/métodos
3.
Environ Pollut ; 352: 124122, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38723707

RESUMO

In viticulture, the use of synthetic chemical formulations introduces insecticide residues into harvested grapes and further into processed grape products, posing a safety concern to consumers. This study investigated the fate of ten insecticide residues and their metabolites from vine to wine. A rapid validated multi-residue approach using QuEChERS extraction and LC-MS/MS configuration was employed for targeted analysis in grape, pomace, and wine. The targeted insecticides showed satisfactory mean recoveries (76.03-111.95%) and precision (RSD = 0.75-7.90%) across the three matrices, with a matrix effect ranging from -16.88 to 35.18%, particularly higher in pomace. Preliminary grape washing effectively removed 15.52-61.31% of insecticide residues based on water solubility and systemic nature. Residue dissipation during fermentation ranged from 73.19% to 87.15% with a half-life spanning from 1 to 5.5 days. The mitigation rate was observed at 12.85-26.81% for wine and 17.76-51.55% for pomace, with the highest transfer rate for buprofezin (51.55%) to pomace and fipronil (25.72%) to wine. Calculated processing factors (PF) for final wine ranged from 0.16 to 0.44, correlating strongly with the octanol-water partition ratio of targeted insecticides. The reported PF, calculated hazard quotient (HQ) (0.003-5.800%), and chronic hazard index (cHI) (2.041-10.387%) indicate reduced residue concentrations in wine and no potential chronic risk to consumers, ensuring a lower dietary risk to wine consumers.

5.
Biochemistry ; 63(10): 1335-1346, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38690768

RESUMO

Lipoxygenases (LOXs) from pathogenic fungi are potential therapeutic targets for defense against plant and select human diseases. In contrast to the canonical LOXs in plants and animals, fungal LOXs are unique in having appended N-linked glycans. Such important post-translational modifications (PTMs) endow proteins with altered structure, stability, and/or function. In this study, we present the structural and functional outcomes of removing or altering these surface carbohydrates on the LOX from the devastating rice blast fungus, M. oryzae, MoLOX. Alteration of the PTMs did notinfluence the active site enzyme-substrate ground state structures as visualized by electron-nuclear double resonance (ENDOR) spectroscopy. However, removal of the eight N-linked glycans by asparagine-to-glutamine mutagenesis nonetheless led to a change in substrate selectivity and an elevated activation energy for the reaction with substrate linoleic acid, as determined by kinetic measurements. Comparative hydrogen-deuterium exchange mass spectrometry (HDX-MS) analysis of wild-type and Asn-to-Gln MoLOX variants revealed a regionally defined impact on the dynamics of the arched helix that covers the active site. Guided by these HDX results, a single glycan sequon knockout was generated at position 72, and its comparative substrate selectivity from kinetics nearly matched that of the Asn-to-Gln variant. The cumulative data from model glyco-enzyme MoLOX showcase how the presence, alteration, or removal of even a single N-linked glycan can influence the structural integrity and dynamics of the protein that are linked to an enzyme's catalytic proficiency, while indicating that extensive glycosylation protects the enzyme during pathogenesis by protecting it from protease degradation.


Assuntos
Lipoxigenase , Glicosilação , Lipoxigenase/metabolismo , Lipoxigenase/química , Lipoxigenase/genética , Especificidade por Substrato , Conformação Proteica , Domínio Catalítico , Processamento de Proteína Pós-Traducional , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Modelos Moleculares , Polissacarídeos/metabolismo , Polissacarídeos/química , Cinética , Ativação Enzimática
7.
Biomed Mater ; 19(3)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38626780

RESUMO

Wool derived keratin, due to its demonstrated ability to promote bone formation, has been suggested as a potential bioactive material for implant surfaces. The aim of this study was to assess the effects of keratin-coated titanium on osteoblast functionin vitroand bone healingin vivo. Keratin-coated titanium surfaces were fabricated via solvent casting and molecular grafting. The effect of these surfaces on the attachment, osteogenic gene, and osteogenic protein expression of MG-63 osteoblast-like cells were quantifiedin vitro. The effect of these keratin-modified surfaces on bone healing over three weeks using an intraosseous calvaria defect was assessed in rodents. Keratin coating did not affect MG-63 proliferation or viability, but enhanced osteopontin, osteocalcin and bone morphogenetic expressionin vitro. Histological analysis of recovered calvaria specimens showed osseous defects covered with keratin-coated titanium had a higher percentage of new bone area two weeks after implantation compared to that in defects covered with titanium alone. The keratin-coated surfaces were biocompatible and stimulated osteogenic expression in adherent MG-63 osteoblasts. Furthermore, a pilot preclinical study in rodents suggested keratin may stimulate earlier intraosseous calvaria bone healing.


Assuntos
Regeneração Óssea , Proliferação de Células , Materiais Revestidos Biocompatíveis , Queratinas , Osteoblastos , Osteogênese , Crânio , Titânio , Titânio/química , Osteoblastos/efeitos dos fármacos , Osteoblastos/citologia , Osteoblastos/metabolismo , Regeneração Óssea/efeitos dos fármacos , Animais , Queratinas/química , Queratinas/metabolismo , Humanos , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Proliferação de Células/efeitos dos fármacos , Crânio/efeitos dos fármacos , Crânio/lesões , Osteogênese/efeitos dos fármacos , Ratos , Propriedades de Superfície , Masculino , Linhagem Celular , Adesão Celular/efeitos dos fármacos , Teste de Materiais , Sobrevivência Celular/efeitos dos fármacos , Ratos Sprague-Dawley
8.
J Neurosurg Spine ; : 1-10, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38608294

RESUMO

OBJECTIVE: Chiari malformations (CMs) are a group of congenital or acquired disorders characterized by hindbrain overcrowding into an underdeveloped posterior cranial fossa. CM is considered largely sporadic-however, there exists growing evidence of transmissible genetic underpinnings. The purpose of this systematic review of all familial studies of CM was to investigate the existence of an inherited component and provide recommendations to manage and monitor at-risk family members. METHODS: This paper includes the following: 1) a unique case report of dizygotic twins who presented at the Toronto Western Hospital Spinal Cord Clinic with symptomatic CM type 1 (CM-1) and syringomyelia; and 2) a systematic review of familial CM. The EMBASE and MEDLINE databases were searched on June 27, 2023, in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Only articles in the English language concerning the diagnosis of CM in > 1 human family member presented as a case study, case series, or literature review were included. RESULTS: Among the 29 articles included in the final analysis, a total of 34 families with CM were analyzed. An average of 3 cases of CM were found per family among all generations. Eighty-one cases (88%) reported CM-1, whereas the other 11 (12%) cases reported either CM-0, CM-1.5, or tonsillar ectopia. A syrinx was present in 37 (54%) cases, with 14 (38%) of these patients also reporting a skeletal abnormality, the most common comorbidity. Most family members diagnosed with CM were siblings (18; 35%), followed by monozygotic twins/triplets (12; 23%). CONCLUSIONS: Patients most often presented with headaches, sensory disturbances, or generalized symptoms. Overall, there exists mounting evidence for a hereditary component of CM. It is unlikely to be explained by a classic mendelian inheritance pattern, but is rather a polygenic architecture influenced by variable penetrance, cosegregation, and entirely nongenetic factors. For first-degree relatives of those affected by CM, the authors' findings may influence clinicians to conduct closer clinical and radiographic monitoring, promote patient education, and consider earlier genetic testing.

9.
Environ Sci Pollut Res Int ; 31(17): 25736-25750, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38488914

RESUMO

A field experiment following good agricultural practices was laid out to study the dissipation of spirotetramat (90 g a.i. ha-1 and 180 g a.i. ha-1) and chlorpyrifos (400 g a.i. ha-1 and 800 g a.i. ha-1) on cabbage heads and soil. Samples were processed using quick, easy, cheap, effective, rugged, and safe (QuEChERS) method for residue estimation of spirotetramat and chlorpyrifos, which were further detected using HPLC-PDA and GC-FPD respectively. The residues of spirotetramat on cabbage heads reached below detection limit (BDL) (< 0.05 mg kg-1) on 7th and 10th day and for chlorpyrifos, BDL (< 0.01 mg kg-1) was achieved on 10th and 15th day for X and 2X dose, respectively. On 20th day after second spray, residues in soil were found to be BDL for both the pesticides. Half-life of spirotetramat and chlorpyrifos was found to be 3 and 2 days, respectively while a safe pre-harvest interval (PHI) of 9 days for spirotetramat and 10 days for chlorpyrifos is suggested on cabbage. The dietary risk assessment studies for various age groups of Indian population, ascertained safety of treated cabbage heads for consumption, as current study revealed that hazard quotient (HQ) < 1 and theoretical maximum dietary intake (TMDI) < maximum permissible intake (MPI) for both the pesticides at respective PHI.


Assuntos
Compostos Aza , Brassica , Clorpirifos , Resíduos de Praguicidas , Praguicidas , Poluentes do Solo , Compostos de Espiro , Solo/química , Brassica/química , Resíduos de Praguicidas/análise , Poluentes do Solo/análise , Praguicidas/análise , Medição de Risco , Meia-Vida
11.
J Biomol Struct Dyn ; : 1-13, 2024 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-38433403

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a life-threatening disease with a survival rate of <5 years. The TGF-ß plays a significant role in the progression and severity of IPF. The TGF-ß receptor type1 TGFBR1 antagonists inhibit the process of fibrosis and may have a role in the treatment of IPF. The main objective of the study was to identify promising drug candidates against IPF using In-silico and In-vitro evaluation methods. An in-silico screening was carried out of the marketed Coxibs to find their TGFBR1 inhibitory potential considering their structural resemblance with the JZO-a co-crystalized ligand of the crystal structure of the TGFBR1. The virtual screening yielded rofecoxib as a TGFBR1 ligand with a significant docking score. To further validate the outcome of molecular docking studies, MD simulation of 200 ns was carried out followed by the determination of conformational stability, binding free energy calculation using MMPBSA/MMGBSA, and Free Energy Landscape (FEL). The therapeutic efficacy of rofecoxib was compared with that of nintedanib (a therapeutic agent used in the treatment of IPF) at equimolar concentrations (5 µM). The model of TGF-ß1 (1 ng/ml)-induced EMT of A549 was used to determine the effect of rofecoxib on the EMT markers like cellular morphology, cytokine expressions, fibrosis associated protein, E-cadherin, and α-smooth muscle actin. In vitro results indicated that rofecoxib significantly suppresses the TGF-ß1-induced EMT of A549 cells and validates the possible preventive/protective role of rofecoxib in pulmonary fibrosis. In conclusion, rofecoxib may be considered for repositioning as an anti-fibrotic agent.Communicated by Ramaswamy H. Sarma.

12.
Prog Mol Biol Transl Sci ; 204: 219-248, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38458739

RESUMO

RNA therapeutics have emerged as potential treatments for genetic disorders, infectious diseases, and cancer. RNA delivery to target cells for efficient therapeutic applications remains challenging due to instability and poor uptake. Polymeric nanoparticulate delivery systems offer stability, protection, and controlled release. These systems shield RNA from degradation, enabling efficient uptake and extended circulation. Various polymeric nanoparticle platforms have been explored, including lipid-based nanoparticles, polymeric micelles, dendrimers, and polymer-drug conjugates. This review outlines recent breakthroughs of recent advances, design principles, characterization techniques, and performance evaluation of these delivery systems. It highlights their potential in translating preclinical studies into clinical applications. Additionally, the review discusses the application of polymeric nanoparticles in ophthalmic drug delivery, particularly for medications that dissolve poorly in water, and the progress made in siRNA-based therapies for viral infections, autoimmune diseases, and cancers. SiRNA holds great promise for precision medicine and therapeutic intervention, with the ability to target specific genes and modulate disease-associated pathways. The versatility and potency of siRNA-based drugs offer a broader scope for therapeutic intervention compared to traditional biological drugs. As research in RNA therapeutics continues to advance, these technologies hold tremendous potential to revolutionize the treatment of various diseases and improve patient outcomes.


Assuntos
Nanopartículas , Neoplasias , Humanos , Neoplasias/terapia , Sistemas de Liberação de Medicamentos , RNA Interferente Pequeno/uso terapêutico , RNA Interferente Pequeno/genética , Polímeros
13.
Cureus ; 16(2): e54794, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38529448

RESUMO

INTRODUCTION: The occurrence of orthopedic injuries during pregnancy carries considerable morbidity and mortality for both the mother and fetus. Successful care of lower limb fractures during pregnancy requires a multidisciplinary approach. Both operative and non-operative treatments must be taken into account by the treating orthopedic physician. There is limited literature available on the management of these lower limb fractures in pregnancy, and peri-operative management of this obstetric and orthopedic trauma is largely unclear. Trauma during pregnancy is a common cause of non-obstetrical maternal death, having a significant public health burden to both the mother and child. The aims and objectives of this study were to review the common causes of lower limb long bone trauma during pregnancy and their functional outcome in terms of morbidity and mortality. This study evaluates various operative and conservative methods of treatment to provide a comprehensive management approach to pregnant patients with lower limb trauma. MATERIALS AND METHODS: A prospective study on functional outcomes of 30 pregnant females who were admitted with lower limb long bone fractures from 2017 to 2021 was done. The patients were randomly selected intra-operatively for various procedures based on the surgeon's preference. All patients were followed for two years or till union occurred, and the radiographic union score for tibial (RUST) and modified radiographic union score for tibial (mRUST) fracture criteria were used to assess bony union clinico-radiologically.  Results: During this study, the mean age of patients was 27 years (range 19-38), having right-side (53.33%) predominance with road traffic accidents (n=22) and falls (n=6) as the most common causes of injury. Two cases of domestic violence were also reported. In our study, the maximum number of cases was 17-25 weeks of their gestation; 12 (40%) patients had tibial fractures, and 18 (60%) had femoral fractures. Six tibial fractures were handled conservatively, while all femoral fractures required surgical intervention. Out of 18 femoral fractures, which were treated surgically, dynamic compression plating was done in 15 (83.33%) patients, while interlock nailing was done in three patients. Six tibial fractures have been operated upon, two (66.66%) with dynamic compression plating and four (33.33%) with an interlocking nail. CONCLUSION: A multidisciplinary approach in terms of both operative and non-operative methods must be taken into account for treating pregnant mothers by the orthopedic physician while carefully weighing the benefits and risks of both procedures. Based on the pattern and displacement of the fracture, many prenatal fractures can be treated conservatively. Another alternative that is frequently safe is to postpone the surgical procedure until childbirth. The physiologic changes associated with pregnancy and any potential dangers to the fetus must be taken into account by the orthopedic surgeon when fractures necessitate surgical intervention. The surgeon is responsible for the patient's correct placement, the C-arm's use, the radiation dose, and the intra-operative fetal monitoring, as well as the danger brought on by anesthetics, antibiotics, analgesics, and anticoagulants.

14.
Clin Exp Dent Res ; 10(1)2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38345476

RESUMO

OBJECTIVES: The objective of this retrospective study was to determine possible prognostic factors of endodontic-periodontal lesions and to compare success, survival, and failure outcomes of treated endodontic-periodontal lesions across different treatment modalities, demographic variables, and anatomical tooth variations. MATERIALS AND METHODS: Data was collected from patient records in the patient management system (Salud, Titanium Solutions) from the Griffith University Dental Clinic between January 2008 and December 2021. The search strategy used the terms "endodontic periodontal lesion," "periodontal endodontic lesion," "endo perio lesion," "perio endo lesion," and "EPL." The 88 cases which met inclusion and exclusion criteria were analyzed. RESULTS: The overall success rate was 46.6%, with 21.6% of teeth surviving and 31.8% of teeth failing. Bone loss extending to the apical third (OR = 0.3, 95% CI [0.104, 0.866]), and probing depths of 5-7 mm (OR = 0.147, 95% CI [0.034, 0.633]) and 8-10 mm (OR = 0.126, 95% CI [0.029, 0.542]) were associated with a statistically significant lower odds of success (p < .05). A history of no periodontal disease (OR = 7.705, 95% CI [1.603, 37.037]) was associated with a statistically significant higher odds of success (p < .05). CONCLUSION: Practitioners should be aware of bone loss to the apical third, deep probing depths, and a history of periodontal disease as possible prognostic factors that can affect the success rate when treating endodontic-periodontal lesions. Further research with more stringent control over operator factors should be done to investigate these variables.


Assuntos
Doenças Periodontais , Dente , Humanos , Estudos Retrospectivos , Prognóstico , Doenças Periodontais/terapia
15.
Dermatol Surg ; 50(5): 407-411, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38349855

RESUMO

BACKGROUND: Avelumab, a programmed death ligand-1 inhibitor, has shown success in providing durable responses for difficult-to-treat Merkel cell carcinomas (MCCs). OBJECTIVE: Evaluate the efficacy and safety of avelumab in the treatment of advanced MCC. METHODS: Studies reporting the use of avelumab as a monotherapy or in combination with other agents in the treatment of stage III or IV (advanced) MCC were included. The primary outcomes were overall response rate, overall survival (OS), and treatment-related adverse events. RESULTS: A total of 48 studies were included, involving 1,565 patients with advanced MCC. Most patients were male (1,051, 67.3%) with stage IV MCC (517, 97.0%). The overall response rate was 46.1% (partial response-25.4% and complete response-20.7%) after a mean follow-up period of 9.5 months. Kaplan-Meier survival curves for the pooled stage III and IV group demonstrated OS rates of 58% at 1 year, 47% at 2 years, and 28% at 5 years after completion of treatment with avelumab (median OS: 23.1 months). The most common treatment-related adverse events consisted of constitutional (44%), gastrointestinal (19%), and dermatologic (12%) symptoms. CONCLUSION: Avelumab monotherapy and combination therapy have shown success in the overall response rate and survival for patients with advanced MCC.


Assuntos
Anticorpos Monoclonais Humanizados , Carcinoma de Célula de Merkel , Neoplasias Cutâneas , Carcinoma de Célula de Merkel/tratamento farmacológico , Carcinoma de Célula de Merkel/patologia , Humanos , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/mortalidade , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/administração & dosagem , Estadiamento de Neoplasias , Antineoplásicos Imunológicos/uso terapêutico , Antineoplásicos Imunológicos/efeitos adversos , Resultado do Tratamento , Taxa de Sobrevida
17.
Int J Radiat Biol ; 100(5): 689-708, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38306495

RESUMO

PURPOSE: This research endeavor was undertaken to elucidate the impact of an innovative ascorbate formulation on the regeneration process of full-thickness excision wounds in a rat model exposed to whole-body gamma irradiation, replicating conditions akin to combat or radiation emergency scenarios. MATERIALS AND METHODS: We established a comprehensive rat model by optimizing whole body γ-radiation doses (5-9 Gy) and full-thickness excision wound sizes (1-3 cm2) to mimic radiation combined injury (RCI). The developed RCI model was used to explore the healing potential of ascorbate formulation. The study includes various treatment groups (i.e., sham control, radiation alone, wound alone, radiation + wound, and radiation + wound + formulation). The ascorbate formulation was applied twice daily, with a 12-hour gap between each application, starting 1 hour after the initiation of the wound. The healing potential of the formulation in the RCI context was evaluated over 14 days through hematological, molecular, and histological parameters. RESULTS: The combination of a 5 Gy radiation dose and a 1 cm2 wound was identified as the optimal setting to develop the RCI model for subsequent studies. The formulation was used topically immediately following RCI, and then twice daily until complete healing. Treatment with the ascorbate formulation yielded noteworthy outcomes and led to a substantial reduction (p < .05) in the wound area, accelerated epithelialization periods, and an increased wound contraction rate. The formulation's localized healing response improved organ weights, normalized blood parameters, and enhanced hematopoietic and immune systems. A gene expression study revealed the treatment up-regulated TGF-ß and FGF, and down-regulated PDGF-α, TNF-α, IL-1ß, IL-6, MIP-1α, and MCP-1 (p < .05). Histopathological assessments supported the formulation's effectiveness in restoring cellular architecture and promoting tissue regeneration. CONCLUSION: Topical application of the ascorbate formulation in RCI resulted in a significant improvement in delayed wound healing, leading to accelerated wound closure by mitigating the expression of inflammatory responses.


Assuntos
Administração Tópica , Ácido Ascórbico , Pele , Cicatrização , Animais , Ácido Ascórbico/farmacologia , Ácido Ascórbico/administração & dosagem , Ratos , Cicatrização/efeitos dos fármacos , Cicatrização/efeitos da radiação , Pele/efeitos da radiação , Pele/efeitos dos fármacos , Pele/lesões , Pele/patologia , Masculino , Modelos Animais de Doenças , Lesões Experimentais por Radiação/tratamento farmacológico , Lesões Experimentais por Radiação/patologia , Ratos Sprague-Dawley , Raios gama , Irradiação Corporal Total
18.
Adv Sci (Weinh) ; 11(16): e2308617, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38421139

RESUMO

The limited availability of molecularly targeted low-molecular-weight imaging agents for monitoring multiple myeloma (MM)-targeted therapies has been a significant challenge in the field. In response, a first-in-class peptide-based radiotracer, [68Ga]Ga-AJ206, is developed that can be seamlessly integrated into the standard clinical workflow and is specifically designed to noninvasively quantify CD38 levels and pharmacodynamics by positron emission tomography (PET). A bicyclic peptide, AJ206, is synthesized and exhibits high affinity to CD38 (KD: 19.1 ± 0.99 × 10-9 m) by surface plasmon resonance. Further, [68Ga]Ga-AJ206-PET shows high contrast within 60 min and suitable absorbed dose estimates for clinical use. Additionally, [68Ga]Ga-AJ206 detects CD38 expression in cell line-derived xenografts, patient-derived xenografts (PDXs), and disseminated disease models in a manner consistent with flow cytometry and immunohistochemistry findings. Moreover, [68Ga]Ga-AJ206-PET successfully quantifies CD38 pharmacodynamics in PDXs, revealing increased CD38 expression in the tumor following all-trans retinoic acid (ATRA) therapy. In conclusion, [68Ga]Ga-AJ206 exhibits the salient features required for clinical translation, providing CD38-specific high-contrast images in multiple models of MM. [68Ga]Ga-AJ206-PET could be useful for quantifying total CD38 levels and pharmacodynamics during therapy to evaluate approved and new therapies in MM and other diseases with CD38 involvement.


Assuntos
ADP-Ribosil Ciclase 1 , Radioisótopos de Gálio , Mieloma Múltiplo , Tomografia por Emissão de Pósitrons , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/diagnóstico por imagem , Animais , ADP-Ribosil Ciclase 1/metabolismo , Camundongos , Humanos , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos/farmacocinética , Modelos Animais de Doenças , Peptídeos/metabolismo , Glicoproteínas de Membrana/metabolismo , Linhagem Celular Tumoral
19.
Colloids Surf B Biointerfaces ; 234: 113745, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38241890

RESUMO

Recent efforts have focused on developing improved drug delivery systems with enhanced therapeutic efficacy and minimal side effects. Micelles, self-assembled from amphiphilic block copolymers in aqueous solutions, have gained considerable attention for drug delivery. However, there is a need to further enhance their efficiency. These micelles offer benefits like biodegradability, biocompatibility, sustained drug release, and improved patient compliance. Yet, researchers must address stability issues and reduce toxicity. Nanoscale self-assembled structures have shown promise as efficient drug carriers, offering an alternative to conventional methods. Fine-tuning at the monomeric and molecular levels, along with structural modifications, is crucial for optimal drug release profiles. Various strategies, such as entrapping hydrophobic drugs and using polyethylene oxide diblock copolymer micelles to resist protein adsorption and cellular adhesion, protect the hydrophobic core from degradation. The polyethylene oxide corona also provides stealth properties, prolonging blood circulation for extended drug administration. Amphiphilic copolymers are attractive for drug delivery due to their adjustable properties, allowing control over micelle size and morphology. Emerging tools promise complex and multifunctional platforms. This article summarizes about the challenges as far as the use of micelles is concerned, including optimizing performance, rigorous pre-clinical and clinical research, and suggests further improvement for drug delivery efficacy.


Assuntos
Sistemas de Liberação de Medicamentos , Micelas , Humanos , Polietilenoglicóis/química , Portadores de Fármacos/química , Polímeros/química
20.
Saudi Pharm J ; 32(2): 101950, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38288131

RESUMO

Detecting z-drugs, a sedative-hypnotic medication, is also misused for criminal activities. Therefore, the analysis of urine samples is crucial for clinical and forensic purposes. We conducted a study where we developed, validated, and compared an analytical method for simultaneously detecting z-drugs in urine samples. Our approach uses the QuEChERS method for sample preparation, combined with liquid chromatography (LC) and gas chromatography (GC) coupled with tandem mass spectrometry (MS/MS). We optimized the QuEChERS method to effectively extract z-drugs from urine samples while minimizing matrix effects and achieving high recovery rates. After extraction, we split the samples into two parts for analysis using LC-MS/MS and GC-MS/MS. We validated our methods, and the results showed good linearity over a broad concentration range (1-200 ng/mL) for each z-drug. The limits of detection and quantification were within clinically relevant ranges, ensuring sensitivity for detecting z-drugs in urine samples. We compared the two chromatographic techniques by analyzing a set of urine samples spiked with known concentrations of z-drugs using both LC-MS/MS and GC-MS/MS methods and then applied to the real samples. The results were statistically analyzed to assess any significant differences in accuracy and precision above 95 %, and both methods offered reliable and consistent results with the samples as well. In conclusion, our analytical method coupled with both LC-MS/MS and GC-MS/MS using the QuEChERS approach provides a comprehensive and robust solution for the simultaneous detection of z-drugs in urine samples. The choice between the two chromatographic techniques can be based on the specific z-drugs of interest and the required analytical performance. This method holds promise for applications in clinical toxicology, forensic analysis, and monitoring z-drug usage.

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