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1.
Methods Mol Biol ; 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38967911

RESUMO

This chapter introduces the increasing significance of mesenchymal stromal/stem cell (MSC) production in regenerative medicine and cellular therapeutics, outlines the growing interest in MSCs for various medical applications, and highlights their potential in advanced therapy medicinal products (ATMPs) and the advancements in cell culture technologies that have facilitated large-scale MSC production under Good Manufacturing Practices (GMP), ensuring safety and efficacy. This chapter describes an optimized upstream protocol for laboratory-scale MSC production from different tissue sources. This protocol, conducted in flasks, controls critical parameters and lays the foundation for downstream processing to generate ATMPs. This comprehensive approach underscores the potential of MSCs in clinical applications and the importance of tailored production processes.

2.
Hum Reprod ; 39(10): 2147-2159, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39066614

RESUMO

Mitochondria are essential organelles with specialized functions, which play crucial roles in energy production, calcium homeostasis, and programmed cell death. In oocytes, mitochondrial populations are inherited maternally and are vital for developmental competence. Dysfunction in mitochondrial quality control mechanisms can lead to reproductive failure. Due to their central role in oocyte and embryo development, mitochondria have been investigated as potential diagnostic and therapeutic targets in assisted reproduction. Pharmacological agents that target mitochondrial function and show promise in improving assisted reproduction outcomes include antioxidant coenzyme Q10 and mitoquinone, mammalian target of rapamycin signaling pathway inhibitor rapamycin, and nicotinamide mononucleotide. Mitochondrial replacement therapies (MRTs) offer solutions for infertility and mitochondrial disorders. Autologous germline mitochondrial energy transfer initially showed promise but failed to demonstrate significant benefits in clinical trials. Maternal spindle transfer (MST) and pronuclear transfer hold potential for preventing mitochondrial disease transmission and improving oocyte quality. Clinical trials of MST have shown promising outcomes, but larger studies are needed to confirm safety and efficacy. However, ethical and legislative challenges complicate the widespread implementation of MRTs.


Assuntos
Mitocôndrias , Doenças Mitocondriais , Terapia de Substituição Mitocondrial , Oócitos , Técnicas de Reprodução Assistida , Humanos , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Terapia de Substituição Mitocondrial/legislação & jurisprudência , Feminino , Doenças Mitocondriais/tratamento farmacológico , Doenças Mitocondriais/terapia , Oócitos/efeitos dos fármacos
3.
Artigo em Inglês | MEDLINE | ID: mdl-38477483

RESUMO

CONTEXT: Proneurotensin (pNT) is associated with obesity and T2D, but the effects of Roux-en-Y gastric bypass (RYGB) on postprandial pNT levels are not well studied. OBJECTIVE: Assess effects of RYGB versus very low-energy diet (VLED) on pNT levels in response to mixed-meal tests (MMT), and long-term effects of RYGB on fasting pNT.Study participants: Cohort 1: Nine normoglycemic (NG) and ten T2D patients underwent MMT before and after VLED, immediately post-RYGB and six weeks post-RYGB. Cohort 2: Ten controls with normal weight and ten patients with obesity and T2D, who underwent RYGB or vertical sleeve gastrectomy (VSG), were subjected to MMTs and GIP infusions pre-surgery and three months post-surgery. GLP-1 infusions were performed in normal weight participants. Cohort 3: Fasting pNT was assessed pre-RYGB (n=161), two months post-RYGB (n=92) and 1-year post-RYGB (n=118) in NG and T2D patients. pNT levels were measured using ELISA. RESULTS: Reduced fasting and postprandial pNT were evident after VLED and immediately following RYGB. Reintroduction of solid food post-RYGB increased fasting and postprandial pNT. Prior to RYGB, all patients lacked a meal response in pNT, but this was evident post-RYGB/VSG. GIP- or GLP-1 infusion had no effect on pNT levels. Fasting pNT were higher 1-year post-RYGB regardless of glycemic status. CONCLUSION: RYGB causes a transient reduction in pNT as a consequence of caloric restriction. The RYGB/VSG-induced rise in postprandial pNT is independent of GIP and GLP-1 and higher fasting pNT are maintained one year post-surgically.

4.
J Prev Alzheimers Dis ; 11(2): 366-374, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38374743

RESUMO

BACKGROUND: PNT001 is a humanized full-length IgG4 S228P monoclonal antibody that binds the cis conformation of the phosphorylated Thr231-Pro232 motif in human full-length (2N4R) tau (cis-pT231 tau) with high selectivity and affinity. It binds selectively to cis-pT231 tau in human tauopathy brain sections, inhibits aggregation of tau, and has shown efficacy in preclinical models of tauopathy. Good Laboratory Practice six-month toxicology studies in cynomolgous monkeys have shown no test article-related findings. OBJECTIVES: To evaluate the safety, tolerability, pharmacokinetics, and immunogenicity of single escalating intravenous doses of PNT001 in healthy volunteers. DESIGN: Phase 1, randomized, double-blind, and placebo-controlled 16-week study. SETTING: Subjects were recruited across three clinical research sites in the United States. PARTICIPANTS: Fifty healthy volunteer subjects enrolled, with 49 receiving the double-blind study drug. INTERVENTION: Six cohorts were administered single escalating doses of PNT001 (33, 100, 300, 900, 2,700, and 4,000 mg). The subjects were randomized 6:2 (PNT001:placebo). MEASUREMENTS: Safety was evaluated by the occurrence of adverse events, electrocardiography, physical examinations, neurological examinations, vital signs, and suicidality. Pharmacokinetics and biomarkers were assessed via serum and cerebrospinal fluid sample analyses. RESULTS: Dose continuation after review of sentinel group data and dose escalation after completion of full cohort data were determined by an external, independent safety board. There were no study pauses or safety concerns identified by the safety board. A total of 49 subjects received the study drugs, with 36 receiving PNT001 and 13 receiving placebo. There were three related non-serious adverse events, each Grade 1, which occurred at the lowest doses and resolved without sequelae. No maximum tolerated dose was identified, and no premature discontinuations, dose reductions, or interruptions due to treatment-related adverse events occurred. One unrelated serious adverse event occurred in a placebo subject with an undisclosed medical condition. No other safety findings were identified. Doses of 900-4,000 mg produced concentrations in the cerebrospinal fluid exceeding the binding affinity constant of PNT001 for cis-pT231 tau (45 ng/mL), indicating that concentrations sufficient for target engagement can be obtained in the cerebrospinal fluid within the tested dose range. The serum pharmacokinetic profile was as expected for a monoclonal antibody. The terminal half-lives ranged from 23.8-33.8 days, and the cerebrospinal fluid exposures were approximately 0.1% of the plasma concentration and dose-proportional. Of the 36 subjects receiving PNT001, one post-baseline positive anti-drug antibody result was observed at Day 112 in a subject who received PNT001 (300 mg). CONCLUSIONS: Single doses of PNT001 were safe and well-tolerated at all dose levels studied, including those doses expected to produce therapeutic benefit. These results support multiple ascending dose trials in patients with neurodegenerative tauopathies for this novel mid-domain tau antibody.


Assuntos
Anticorpos Monoclonais , Tauopatias , Humanos , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Método Duplo-Cego , Voluntários Saudáveis , Tauopatias/imunologia , Tauopatias/terapia , Estados Unidos , Proteínas tau/imunologia
5.
Sensors (Basel) ; 23(13)2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37447847

RESUMO

Atomic clocks are highly precise timing devices used in numerous Positioning, Navigation, and Timing (PNT) applications on the ground and in outer space. In recent years, however, more precise timing solutions based on optical technology have been introduced as current technology capabilities advance. State-of-the-art optical clocks-predicted to be the next level of their predecessor atomic clocks-have achieved ultimate uncertainty of 1 × 10-18 and beyond, which exceeds the best atomic clock's performance by two orders of magnitude. Hence, the successful development of optical clocks has drawn significant attention in academia and industry to exploit many more opportunities. This paper first provides an overview of the emerging optical clock technology, its current development, and characteristics, followed by a clock stability analysis of some of the successfully developed optical clocks against current Global Navigation Satellite System (GNSS) satellite clocks to discuss the optical clock potentiality in GNSS positioning. The overlapping Allan Deviation (ADEV) method is applied to estimate the satellite clock stability from International GNSS Service (IGS) clock products, whereas the optical clock details are sourced from the existing literature. The findings are (a) the optical clocks are more stable than that of atomic clocks onboard GNSS satellites, though they may require further technological maturity to meet spacecraft payload requirements, and (b) in GNSS positioning, optical clocks could potentially offer less than a 1 mm range error (clock-related) in 30 s and at least 10 times better timing performance after 900 s in contrast to the Galileo satellite atomic clocks-which is determined in this study as the most stable GNSS atomic clock type used in satellite positioning.


Assuntos
Indústrias , Astronave , Tecnologia , Incerteza
6.
Sensors (Basel) ; 23(10)2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37430782

RESUMO

Satellite navigation over recent decades has become the default and, in some cases, sole source of positioning for maritime vessels. The classic sextant has been all but forgotten by a significant number of ship navigators. However, recent risks to RF-derived positioning by jamming and spoofing have resurfaced the need to train sailors again in the art. Innovations in space optical navigation have long been perfecting the art of using celestial bodies and horizons to determine a space vessel's attitude and position. This paper explores their application to the much older ship navigation problem. Models are introduced that utilize the stars and horizon to derive latitude and longitude. When assuming good star visibility conditions on the ocean, the accuracy delivered is at the 100 m level. This can meet requirements for ship navigation in coastal and oceanic voyages.

7.
Biomedicines ; 11(7)2023 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-37509447

RESUMO

Traumatic brain injury (TBI) results in the generation of tau. As hyperphosphorylated tau (p-tau) is one of the major consequences of TBI, targeting p-tau in TBI may lead to the development of new therapy. Twenty-five pigs underwent a controlled cortical impact. One hour after TBI, pigs were administered either vehicle (n = 13) or PNT001 (n = 12), a monoclonal antibody for the cis conformer of tau phosphorylated at threonine 231. Plasma biomarkers of neural injury were assessed for 14 days. Diffusion tensor imaging was performed at day 1 and 14 after injury, and these were compared to historical control animals (n = 4). The fractional anisotropy data showed significant white matter injury for groups at 1 day after injury in the corona radiata. At 14 days, the vehicle-treated pigs, but not the PNT001-treated animals, exhibited significant white matter injury compared to sham pigs in the ipsilateral corona radiata. The PNT001-treated pigs had significantly lower levels of plasma glial fibrillary acidic protein (GFAP) at day 2 and day 4. These findings demonstrate a subtle reduction in the areas of white matter injury and biomarkers of neurological injury after treatment with PNT001 following TBI. These findings support additional studies for PNT001 as well as the potential use of this agent in clinical trials in the near future.

8.
BJU Int ; 132(1): 65-74, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36797449

RESUMO

OBJECTIVE: To assess the efficacy of 177 Lu-PNT2002, a novel radiolabelled small molecule that binds with high affinity to prostate-specific membrane antigen (PSMA), in combination with stereotactic body radiotherapy (SBRT) to all sites of metastasis, vs SBRT alone, in men with oligorecurrent metastatic hormone-sensitive prostate cancer (mHSPC). PATIENTS AND METHODS: The 177 Lutetium-PSMA Neoadjuvant to Ablative Radiotherapy for Oligorecurrent Prostate Cancer (LUNAR) trial is an open-label, randomized, stratified, two-arm, single-centre, Phase 2 trial to compare the efficacy and safety of neoadjuvant 177 Lu-PNT2002 plus SBRT vs SBRT alone in men with oligorecurrent mHSPC. Key eligibility criteria include one to five lesions identified on a PSMA positron emission tomography (PET)/computed tomography (CT) scan centrally reviewed by a board-certified nuclear medicine physician. Key exclusion criteria include castrate-resistant disease, de novo oligometastatic disease and receipt of androgen deprivation therapy (ADT) within 6 months of trial enrolment. The trial aims to enrol 100 patients who will be centrally randomized to one of the two treatment arms, in a 1:1 ratio. Patients in the control arm receive SBRT to all sites of disease. Patients in the experimental arm receive two cycles of neoadjuvant 177 Lu-PNT2002 (6.8 GBq) 6-8 weeks apart, followed by an interval PSMA PET/CT in 4-6 weeks and dose-adapted SBRT to all sites of disease 1-2 weeks later. The primary endpoint is progression-free survival. Secondary endpoints are radiographic and prostate-specific antigen-based progression, acute and late physician-scored toxicity, patient-reported quality of life, ADT-free survival, time to progression, overall survival, locoregional control, and duration of response. Enrolment in the study commenced in September 2022. RESULTS AND CONCLUSIONS: The addition of 177 Lu-PNT2002 to metastasis-directed therapy alone may potentially further forestall disease progression. The results of this Phase 2 trial will determine, for the first time in a randomized fashion, the added benefit of 177 Lu-PNT2002 to SBRT in patients with oligorecurrent mHSPC.


Assuntos
Neoplasias de Próstata Resistentes à Castração , Neoplasias da Próstata , Masculino , Humanos , Neoplasias da Próstata/patologia , Lutécio/uso terapêutico , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Qualidade de Vida , Terapia Neoadjuvante , Antagonistas de Androgênios/uso terapêutico , Antígeno Prostático Específico , Neoplasias de Próstata Resistentes à Castração/patologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Ensaios Clínicos Fase II como Assunto
9.
Quant Imaging Med Surg ; 13(1): 94-107, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36620179

RESUMO

Background: The aim of this study was to evaluate the effect of a model combining a 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT)-based radiomics signature with clinical factors in the preoperative prediction of the International Neuroblastoma Pathology Classification (INPC) type of pediatric peripheral neuroblastic tumor (pNT). Methods: A total of 106 consecutive pediatric pNT patients confirmed by pathology were retrospectively analyzed. Significant features determined by multivariate logistic regression were retained to establish a clinical model (C-model), which included clinical parameters and PET/CT radiographic features. A radiomics model (R-model) was constructed on the basis of PET and CT images. A semiautomatic method was used for segmenting regions of interest. A total of 1,016 radiomics features were extracted. Univariate analysis and the least absolute shrinkage selection operator were then used to select significant features. The C-model was combined with the R-model to establish a combination model (RC-model). The predictive performance was validated by receiver operating characteristic (ROC) curve analysis, calibration curves, and decision curve analysis (DCA) in both the training cohort and validation cohort. Results: The radiomics signature was constructed using 5 selected radiomics features. The RC-model, which was based on the 5 radiomics features and 3 clinical factors, showed better predictive performance compared with the C-model alone [area under the curve in the validation cohort: 0.908 vs. 0.803; accuracy: 0.903 vs. 0.710; sensitivity: 0.895 vs. 0.789; specificity: 0.917 vs. 0.583; net reclassification improvement (NRI) 0.439, 95% confidence interval (CI): 0.1047-0.773; P=0.01]. The calibration curve showed that the RC-model had goodness of fit, and DCA confirmed its clinical utility. Conclusions: In this preliminary single-center retrospective study, an R-model based on 18F-FDG PET/CT was shown to be promising in predicting INPC type in pediatric pNT, allowing for the noninvasive prediction of INPC and assisting in therapeutic strategies.

10.
Drug Chem Toxicol ; 46(2): 380-391, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35188013

RESUMO

Androgen deprivation therapy is commonly used for the treatment of prostate cancer. Enzalutamide is a next-generation androgen receptor inhibitor, initially approved to treat castration-resistance prostate cancer. Lupeol, a triterpene present in various fruits, vegetables, has anti-oxidant and anti-proliferative activity. The present study aimed to evaluate the Enzalutamide-induced toxicity and its possible amelioration by Lupeol. We performed multiple in vitro and in vivo experiments to conclude our hypothesis. The results revealed that both Enzalutamide and Lupeol interact with DNA through electrostatic interactions. Enzalutamide (5-20 µM) caused cytotoxicity in both normal (PNT2) and cancer cells (LNCaP and 22Rv1). However, Lupeol (10-50 µM) specifically killed the cancer cells while sparing normal cells. The study further revealed that Lupeol could attenuate Enzalutamide-induced cytotoxicity and genotoxicity (chromosomal aberrations and micronucleus formation) to normal cells and potentially induce cytotoxicity to transformed cells. We further observed that Lupeol (40 mg/kg) mediated attenuation of the Enzalutamide (10 mg/kg) induced oxidative and DNA damages. Our study also revealed that Lupeol reverses the Enzalutamide-induced hepatic and renal damages. In conclusion, our study indicates that Lupeol can be used as an adjuvant for reducing the toxic effects and enhancing the effectiveness of Enzalutamide.


Assuntos
Neoplasias da Próstata , Triterpenos , Masculino , Humanos , Triterpenos/farmacologia , Antagonistas de Androgênios/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Triterpenos Pentacíclicos , Nitrilas/farmacologia , Receptores Androgênicos/genética , Linhagem Celular Tumoral
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