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1.
Biointerphases ; 19(4)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38975887

RESUMO

A promising research direction in the field of biological engineering is the design and functional programming of three-dimensional (3D) biointerfaces designed to support living cell functionality and growth in vitro, offering a route to precisely regulate cellular behaviors and phenotypes for addressing therapeutic challenges. While traditional two-dimensional (2D) biointerfaces have provided valuable insights, incorporating specific signaling cues into a 3D biointeractive microenvironment at the right locations and time is now recognized as crucial for accurately programming cellular decision-making and communication processes. This approach aims to engineer cell-centric microenvironments with the potential to recapitulate complex biological functions into a finite set of growing cellular organizations. Additionally, they provide insights into the hierarchical logic governing the relationship between molecular components and higher-order multicellular functionality. The functional live cell-based microenvironment engineered through such innovative biointerfaces has the potential to be used as an in vitro model system for expanding our understanding of cellular behaviors or as a therapeutic habitat where cellular functions can be reprogrammed.


Assuntos
Transdução de Sinais , Animais , Humanos , Microambiente Celular , Engenharia Tecidual/métodos
2.
ACS Appl Mater Interfaces ; 16(27): 35361-35371, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38940634

RESUMO

Nanomaterials shaped as rings are interesting nanostructures with control of the materials properties at the nanoscale. Nanoring plasmonic resonators provide tunable optical resonances in the near-infrared with application in sensing. Fabrication of nanorings can be carried out via top-down approaches based on electron beam lithography with high control of the ring size parameters but at high cost. Alternatively, fabrication via self-assembly approaches has a higher speed/lower cost but at the cost of control of ring parameters. Current colloidal lithography approaches can provide nanoring fabrication over large areas but only of specific materials and a select set of rings (large ring diameters or small rings with ultrathin walls). We extend Hole-mask Colloidal Lithography to use ring shaped holes, allow the deposition of arbitrary materials, and allow the independent tuning of ring-wall thickness over a large range of values. We present a generic approach for the fabrication of nanorings formed from a range of materials including low cost (e.g., Cu, Al) and nonplasmonic (e.g., W) materials and with control of ring wall thickness and diameter allowing tuning of ring parameters and materials for applications in nanooptics and beyond.

3.
ACS Appl Mater Interfaces ; 16(17): 21534-21545, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38634566

RESUMO

Nanoscale biomolecular placement is crucial for advancing cellular signaling, sensor technology, and molecular interaction studies. Despite this, current methods fall short in enabling large-area nanopatterning of multiple biomolecules while minimizing nonspecific interactions. Using bioorthogonal tags at a submicron scale, we introduce a novel hole-mask colloidal lithography method for arranging up to three distinct proteins, DNA, or peptides on large, fully passivated surfaces. The surfaces are compatible with single-molecule fluorescence microscopy and microplate formats, facilitating versatile applications in cellular and single-molecule assays. We utilize fully passivated and transparent substrates devoid of metals and nanotopographical features to ensure accurate patterning and minimize nonspecific interactions. Surface patterning is achieved using bioorthogonal TCO-tetrazine (inverse electron-demand Diels-Alder, IEDDA) ligation, DBCO-azide (strain-promoted azide-alkyne cycloaddition, SPAAC) click chemistry, and biotin-avidin interactions. These are arranged on surfaces passivated with dense poly(ethylene glycol) PEG brushes crafted through the selective and stepwise removal of sacrificial metallic and polymeric layers, enabling the directed attachment of biospecific tags with nanometric precision. In a proof-of-concept experiment, DNA tension gauge tether (TGT) force sensors, conjugated to cRGD (arginylglycylaspartic acid) in nanoclusters, measured fibroblast integrin tension. This novel application enables the quantification of forces in the piconewton range, which is restricted within the nanopatterned clusters. A second demonstration of the platform to study integrin and epidermal growth factor (EGF) proximal signaling reveals clear mechanotransduction and changes in the cellular morphology. The findings illustrate the platform's potential as a powerful tool for probing complex biochemical pathways involving several molecules arranged with nanometer precision and cellular interactions at the nanoscale.


Assuntos
Química Click , DNA , DNA/química , Técnicas Biossensoriais/métodos , Propriedades de Superfície , Animais , Camundongos , Azidas/química , Biotina/química , Nanoestruturas/química , Polietilenoglicóis/química , Ligantes , Avidina/química
5.
Nat Commun ; 15(1): 1224, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38336934

RESUMO

The peripheral immune system is important in neurodegenerative diseases, both in protecting and inflaming the brain, but the underlying mechanisms remain elusive. Alzheimer's Disease is commonly preceded by a prodromal period. Here, we report the presence of large Aß aggregates in plasma from patients with mild cognitive impairment (n = 38). The aggregates are associated with low level Alzheimer's Disease-like brain pathology as observed by 11C-PiB PET and 18F-FTP PET and lowered CD18-rich monocytes. We characterize complement receptor 4 as a strong binder of amyloids and show Aß aggregates are preferentially phagocytosed and stimulate lysosomal activity through this receptor in stem cell-derived microglia. KIM127 integrin activation in monocytes promotes size selective phagocytosis of Aß. Hydrodynamic calculations suggest Aß aggregates associate with vessel walls of the cortical capillaries. In turn, we hypothesize aggregates may provide an adhesion substrate for recruiting CD18-rich monocytes into the cortex. Our results support a role for complement receptor 4 in regulating amyloid homeostasis.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Disfunção Cognitiva , Humanos , Doença de Alzheimer/patologia , Integrina alfaXbeta2 , Monócitos/patologia
6.
J Wildl Dis ; 60(1): 116-125, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37889935

RESUMO

Eastern barred bandicoots (Perameles gunnii) are thought to be highly susceptible to disease caused by infection with the protozoan parasite Toxoplasma gondii. This study followed a population of 67 P. gunnii introduced onto the Summerland Peninsula, Phillip Island, Australia, where the prevalence of T. gondii infection in the feral cat population was known to be very high. Prior to release, bandicoots were tested for serologic exposure to T. gondii using the modified agglutination test. A subset of bandicoots was tested on four occasions after release onto the peninsula. No seroconversion was detected at any time point. A subset of bandicoots was radiotracked after release and at two additional trapping sessions to help monitor survival. Toxoplasma gondii DNA was not detected by PCR in eight carcasses recovered for necropsy. Fourteen founder bandicoots (21% of founders) were known to be alive at 500 d post-release. A total of 29 unmarked bandicoots were trapped over the study period, confirming that the bandicoots were successfully reproducing on the island. Body weight, packed cell volume, and total plasma protein were used as measures of individual animal health; population health was inferred from these data. Body weight was significantly associated with trip number, with a general trend of increasing weight after release onto the island. This study showed that eastern barred bandicoots were able to establish a new population despite a probably high environmental load of T. gondii.


Assuntos
Doenças do Gato , Marsupiais , Toxoplasma , Toxoplasmose Animal , Animais , Gatos , Vitória , Animais Selvagens , Marsupiais/parasitologia , Peso Corporal , Toxoplasmose Animal/epidemiologia , Anticorpos Antiprotozoários
7.
Semin Nucl Med ; 54(1): 4-13, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37400321

RESUMO

Prostate cancer is the second most common cancer in men worldwide. [18F]FDG PET/CT imaging, a well-known and effective technique for detecting malignancies, has not been considered a useful tool for prostate cancer imaging by many because of its perceived low [18F]FDG uptake. Incidentally detected focal [18F]FDG uptake in the prostate is not uncommon, and typically benign. Imaging features that would increase concern for an underlying prostatic carcinoma, include focal uptake in the periphery near the gland margin without calcifications. [18F]FDG PET/CT imaging provides little value in the initial staging of prostate cancer, particularly in the era of prostate specific membrane antigen (PSMA) radiotracer. In cases of biochemical recurrence, the value of [18F]FDG PET/CT increases notably when Grade group 4 or 5 and elevated PSA levels are present. Active research is underway for theranostic approaches to prostate cancer, including [177Lu]Lu-PSMA therapy. Dual tracer staging using FDG and PSMA imaging significantly enhances the accuracy of disease site assessment. Specifically, the addition of [18F]FDG PET/CT imaging allows for the evaluation of discordant disease (PSMA negative/FDG positive). The maximal benefit from [177Lu]Lu-PSMA therapy relies on significant PSMA accumulation across all disease sites, and the identification of discordant disease suggests that these patients may derive less benefit from the treatment. The genuine value of [18F]FDG PET/CT imaging lies in advanced prostate cancer, PSMA-negative disease, as a prognostic biomarker, and the realm of new targeted theranostic agents.


Assuntos
Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias da Próstata , Masculino , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Fluordesoxiglucose F18 , Antígeno Prostático Específico , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/terapia , Neoplasias da Próstata/patologia , Tomografia por Emissão de Pósitrons , Radioisótopos de Gálio
8.
Biomaterials ; 301: 122244, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37459700

RESUMO

Biochemical and biomechanical signals regulate stem cell function in the niche environments in vivo. Current in vitro culture of mouse embryonic stem cells (mESC) uses laminin (LN-511) to provide mimetic biochemical signaling (LN-521 for human systems) to maintain stemness. Alternative approaches propose topographical cues to provide biomechanical cues, however combined biochemical and topographic cues may better mimic the in vivo environment, but are largely unexplored for in vitro stem cell expansion. In this study, we directly compare in vitro signals from LN-511 and/or topographic cues to maintain stemness, using systematically-varied submicron pillar patterns or flat surfaces with or without preadsorbed LN-511. The adhesion of cells, colony formation, expression of the pluripotency marker,octamer-binding transcription factor 4 (Oct4), and transcriptome profiling were characterized. We observed that either biochemical or topographic signals could maintain stemness of mESCs in feeder-free conditions, indicated by high-level Oct4 and gene profiling by RNAseq. The combination of LN-511 with nanotopography reduced colony growth, while maintaining stemness markers, shifted the cellular phenotype indicating that the integration of biochemical and topographic signals is antagonistic. Overall, significantly faster (up to 2.5 times) colony growth was observed at nanotopographies without LN-511, suggesting for improved ESC expansion.


Assuntos
Células-Tronco Embrionárias , Células-Tronco Embrionárias Murinas , Animais , Camundongos , Humanos , Células Cultivadas , Ligantes , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Fenótipo , Diferenciação Celular/fisiologia
9.
Ther Adv Med Oncol ; 15: 17588359231177018, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37323189

RESUMO

Reported here is a case of rapidly progressive metastatic castration-resistant prostate cancer treated with [177Lu]Lu-PSMA-617 in the setting of severe renal impairment and impending ureteric obstruction. PSMA is expressed on renal tubular cells, raising the possibility of radiation-induced nephrotoxicity, and this level of renal impairment would typically exclude the patient from [177Lu]Lu-PSMA-617 therapy. Multidisciplinary input, individualized dosimetry, and patient-specific dose reduction were used to ensure the cumulative dose to the kidneys remained within acceptable limits. He was initially planned for treatment with six cycles of [177Lu]Lu-PSMA-617. However, he had an excellent response to therapy following four cycles of treatment and the last two cycles were omitted. He has been followed for 1-year posttherapy without evidence of disease recurrence. No acute or chronic nephrotoxicity was observed. This case report highlights the utility of [177Lu]Lu-PSMA-617 therapy in severe renal impairment and provides evidence of relative safety in patients who would otherwise not be considered candidates for therapy.


This report presents a case of a man with aggressive metastatic prostate cancer who received [177Lu]Lu-PSMA-617 therapy, despite having severely reduced kidney function and worsening ureter obstruction. This treatment could have potential side effects on kidney function, but the medical team used a personalized approach to reduce patient risk. The man was initially planned to have six cycles of therapy, but his excellent response to treatment after four cycles meant the last two cycles were not given. The man has been followed for 1 year after treatment and has not experienced any worsening kidney function. This case shows the safe and effective use of [177Lu]Lu-PSMA-617 therapy in a patient with severely reduced kidney function who would not normally qualify for this treatment.

10.
Front Physiol ; 14: 1176409, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37168225

RESUMO

Serial intravital 2-photon microscopy of the kidney and other abdominal organs is a powerful technique to assess tissue function and structure simultaneously and over time. Thus, serial intravital microscopy can capture dynamic tissue changes during health and disease and holds great potential to characterize (patho-) physiological processes with subcellular resolution. However, successful image acquisition and analysis require significant expertise and impose multiple potential challenges. Abdominal organs are rhythmically displaced by breathing movements which hamper high-resolution imaging. Traditionally, kidney intravital imaging is performed on inverted microscopes where breathing movements are partly compensated by the weight of the animal pressing down. Here, we present a custom and easy-to-implement setup for intravital imaging of the kidney and other abdominal organs on upright microscopes. Furthermore, we provide image processing protocols and a new plugin for the free image analysis software FIJI to process multichannel fluorescence microscopy data. The proposed image processing pipelines cover multiple image denoising algorithms, sample drift correction using 2D registration, and alignment of serial imaging data collected over several weeks using landmark-based 3D registration. The provided tools aim to lower the barrier of entry to intravital microscopy of the kidney and are readily applicable by biomedical practitioners.

11.
Biol Reprod ; 107(5): 1177-1204, 2022 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-35947985

RESUMO

Oogenesis and folliculogenesis are considered as complex and species-specific cellular differentiation processes, which depend on the in vivo ovarian follicular environment and endocrine cues. Considerable efforts have been devoted to driving the differentiation of female primordial germ cells toward mature oocytes outside of the body. The recent experimental attempts have laid stress on offering a suitable microenvironment to assist the in vitro folliculogenesis and oogenesis. Despite developing a variety of bioengineering techniques and generating functional mature gametes through in vitro oogenesis in earlier studies, we still lack knowledge of appropriate microenvironment conditions for building biomimetic culture systems for female fertility preservation. Therefore, this review paper can provide a source for a large body of scientists developing cutting-edge in vitro culture systems for female germ cells or setting up the next generation of reproductive medicine as feasible options for female infertility treatment. The focal point of this review outlines advanced bioengineering technologies such as 3D biofabricated hydrogels/scaffolds and microfluidic systems utilized with female germlines for fertility preservation through in vitro folliculogenesis and oogenesis.


Assuntos
Oogênese , Folículo Ovariano , Feminino , Animais , Fertilidade , Células Germinativas , Bioengenharia , Oócitos
12.
ACS Nano ; 16(7): 10392-10403, 2022 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-35801826

RESUMO

Staphylococcus aureus is a widespread and highly virulent pathogen that can cause superficial and invasive infections. Interactions between S. aureus surface receptors and the extracellular matrix protein fibronectin mediate the bacterial invasion of host cells and is implicated in the colonization of medical implant surfaces. In this study, we investigate the role of distribution of both fibronectin and cellular receptors on the adhesion of S. aureus to interfaces as a model for primary adhesion at tissue interfaces or biomaterials. We present fibronectin in patches of systematically varied size (100-1000 nm) in a background of protein and bacteria rejecting chemistry based on PLL-g-PEG and studied S. aureus adhesion under flow. We developed a single molecule imaging assay for localizing fibronectin binding receptors on the surface of S. aureus via the super-resolution DNA points accumulation for imaging in nanoscale topography (DNA-PAINT) technique. Our results indicate that S. aureus adhesion to fibronectin biointerfaces is regulated by the size of available ligand patterns, with an adhesion threshold of 300 nm and larger. DNA-PAINT was used to visualize fibronectin binding receptor organization in situ at ∼7 nm localization precision and with a surface density of 38-46 µm-2, revealing that the engagement of two or more receptors is required for strong S. aureus adhesion to fibronectin biointerfaces.


Assuntos
Infecções Estafilocócicas , Staphylococcus aureus , Humanos , Staphylococcus aureus/metabolismo , Fibronectinas/metabolismo , Aderência Bacteriana , Integrina alfa5beta1/metabolismo , DNA/metabolismo , Adesinas Bacterianas/metabolismo
13.
Small Methods ; 6(6): e2200152, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35451210

RESUMO

Hemidesmosomes (HDs) are multiprotein complexes that firmly anchor epidermal cells to the basement membrane of skin through the interconnection of the cytoplasmic intermediate filaments with extracellular laminin 332 (Ln332). Considerably less attention has been paid to HDs compared to focal complexes/focal adhesions (FC/FAs) in mechanistic single-cell structures due to the lack of suitable in vitro model systems. Here nanopatterns of Ln332 (100-1000 nm) are created to direct and study the formation of HD in adherent HaCaT cells. It is observed that HaCaT cells at Ln 332 nanopatterns adhere via hemidesmosomes, in stark contrast to cells at homogeneous Ln332 surfaces that adhere via FC/FAs. Clustering of α6 integrin is observed at nanopatterned Ln332 of 300 nm patches and larger. Cells at 500 nm diameter patterns show strong colocalization of α6 integrin with ColXVII or pan-cytokeratin compared to 300 nm/1000 nm indicating a threshold for HD initiation >100 nm but a pattern size selection for maturation of HDs. It is demonstrated that the pattern of Ln332 can determine the cellular selection of adhesion types with a size-dependent initiation and maturation of HDs. The protein nanopatterning approach that is presented provides a new in vitro route to study the role of HDs in cell signaling and function.


Assuntos
Adesões Focais , Hemidesmossomos , Adesão Celular , Adesões Focais/metabolismo , Integrina alfa6/metabolismo , Ligantes
14.
Curr Radiopharm ; 15(2): 123-133, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35135467

RESUMO

BACKGROUND: Peptide receptor radionuclide therapy (PRRT) has been recently approved for advanced, metastatic, or progressive neuroendocrine tumors (NETs). OBJECTIVE: This study reports the adverse events (AEs) observed with patient-tailored administered activity. METHODS: Fifty-two PRRT naive patients were treated with 177Lu-DOTATATE. The administered activity ranges between 2.78 and 5.55 GBq/cycle using the patient's unique characteristics (age, symptoms, blood work, and biomarkers). RESULTS: The protocol was well tolerated with the overwhelming majority of participants being forty- six (88%), completing all 4 induction therapy cycles. The median cumulative administered activity was 19.6 GBq (ranged 3.8-22.3 GBq). A total of 42/52 (81%) reported at least one symptom, and 43/52 (83%) had evidence of biochemical abnormality at enrollment that would meet grade 1 or 2 criteria for AEs. These symptoms only slightly increase with treatment to 50/52 (96%) and 51/52 (98%), respectively. The most common symptoms were mild fatigue (62%), shortness of breath (50%), nausea (44%), abdominal pain (38%), and musculoskeletal pain (37%). The most common biomarker abnormalities were mild anemia (81%), reduced estimated glomerular filtration rate (eGFR) (58%), increased alkaline phosphatase (ALP) (50%), and leukopenia (37%). Of critical importance, no 177Lu-DOTATATE related grade 3 or 4 AEs were observed. CONCLUSION: Tailoring the administered activity of 177Lu-DOTATATE to the individual patient with a variety of NETs is both safe and well-tolerated. No patient developed severe grade 3 or 4 AEs. Most patients exhibit symptoms or biochemical abnormality before treatment and this only slightly worsens following induction therapy.


Assuntos
Tumores Neuroendócrinos , Compostos Organometálicos , Ensaios Clínicos Fase II como Assunto , Compostos Heterocíclicos com 1 Anel , Humanos , Tumores Neuroendócrinos/radioterapia , Octreotida/efeitos adversos , Compostos Organometálicos/efeitos adversos , Tomografia por Emissão de Pósitrons , Cintilografia , Compostos Radiofarmacêuticos/efeitos adversos , Sistema de Registros
15.
Artif Cells Nanomed Biotechnol ; 50(1): 29-39, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35132929

RESUMO

Co-delivery of anticancer drugs and biologics can provide synergetic effects and outperform single delivery therapies. Here, a nanoparticle (NP) system for co-delivery of methotrexate (MTX) and STAT3 siRNA has been developed and tested in vitro. Mesoporous silica nanoparticles (MSNs) were functionalized with chitosan (ch) by covalent grafting mediated by aminopropyl triethoxysilane (APTES) via glutaraldehyde as the linker. Co-delivery of MTX and STAT3 siRNA to MCF7 cells was demonstrated in cells by flow cytometric analysis and confocal laser scanning fluorescence microscopy for use in breast cancer treatment. MTX either competitively inhibits the dihydrofolate reductase (DHFR) receptor or suppresses the STAT3 metabolic pathway. STAT3 protein plays an essential role in cell division, proliferation and survival. Reduction of the protein by both MTX and STAT3 siRNA, achieved by chMSNs, significantly decreased the viability of breast cancer cells compared to single treatments alone. Cellular uptake of modified NPs was increased over time when additional free MTX was added implicating the DHFR receptor in uptake. In addition, protein corona compositions coated the NPs outer surface, were different between the NPs with and without drug potentially modulating cellular uptake. This study is the first report on co-delivery of MTX and STAT3 siRNA by chitosan modified MSNs.


Assuntos
Neoplasias da Mama , Nanopartículas , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos , Feminino , Humanos , Metotrexato/farmacologia , Metotrexato/uso terapêutico , RNA Interferente Pequeno/genética , Fator de Transcrição STAT3/genética
16.
ACS Nano ; 16(1): 1102-1118, 2022 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-34982538

RESUMO

Nanoparticles (NPs) can modulate protein aggregation and fibril formation in the context of amyloid diseases. Understanding the mechanism of this action remains a critical next step in developing nanomedicines for the treatment or prevention of Parkinson's disease. α-Synuclein (α-Syn) can undergo interactions of different strength with nanoparticles, and these interactions can be prevented by the presence of a protein corona (PC) acquired during the exposure of NPs to serum proteins. Here, we develop a method to attach the PC irreversibly to the NPs, which enables us to study in detail the interaction of α-Syn and polyethylenimine-coated carboxyl-modified polystyrene NPs (PsNPs-PEI) and the role of the dynamics of the interactions. Analysis of the kinetics of fibril formation reveals that the NPs surface promotes the primary nucleation step of amyloid fibril formation without significantly affecting the elongation and fragmentation steps or the final equilibrium. Furthermore, the results show that even though α-Syn can access the surface of NPs that are precoated with a PC, due to the dynamic nature of the PC proteins, the PC nevertheless reduces the acceleratoring effect of the NPs. This effect is likely to be caused by reducing the overall amount of weakly interacting α-Syn molecules on the NP surface and the access of further α-Syn required for fibril elongation. Our experimental approach provides microscopic insight into how serum proteins can modulate the complex interplay between NPs and amyloid proteins.


Assuntos
Nanopartículas , Coroa de Proteína , alfa-Sinucleína/metabolismo , Amiloide/metabolismo , Proteínas Amiloidogênicas
17.
J Cancer Res Clin Oncol ; 148(1): 225-236, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34110489

RESUMO

PURPOSE: 177Lu-Dotatate is an emerging treatment modality for patients with unresectable or metastatic well-differentiated NETs. This study examines survival predictors in patients who received 177Lu-Dotatate. METHODS: A retrospective single-center review was conducted, examining 47 individuals with progressive well-differentiated NETs treated with 177Lu-Dotatate (four induction cycles of 5.5 GBq at 10-week intervals followed by eight maintenance cycles of 3.7 GBq at 6-month intervals). RESULTS: Median follow-up was 63.1 months with a median progression-free survival (PFS) of 34.1 months. However, median overall survival (OS) was not reached at the time of analysis. The presence of ≥ 5 bone metastases (hazard ratio HR 4.33; p = 0.015), non-gastroenteropancreatic (non-GEP) NETs (HR 3.22; p = 0.025) and development of interim ascites (HR 3.15; p = 0.047) independently predicted a worse OS. Patients with chromogranin A of ≥ 4 × upper limit of normal (ULN) had shorter OS (p < 0.001) and PFS (p = 0.004). Similarly, those with pre-existing ascites demonstrated a worse OS (p = 0.009) and PFS (p = 0.026). Liver metastases involving greater than 50% liver volume and the existence of unusual metastatic locations had a negative impact on OS (p = 0.033) and PFS (p = 0.026), respectively. CONCLUSION: High burden of skeletal and hepatic metastases, non-GEP-NETs, chromogranin A of ≥ 4 × ULN, unusual metastatic sites, pre-existing and interim ascites are predictors of poor outcomes in patients treated with 177Lu-Dotatate. These common indicators can be used for the risk stratification and identification of patients most likely to benefit from PRRT. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02236910, Retrospectively registered on September, 2014.


Assuntos
Neoplasias Ósseas/secundário , Neoplasias Hepáticas/secundário , Tumores Neuroendócrinos/mortalidade , Tumores Neuroendócrinos/radioterapia , Octreotida/análogos & derivados , Compostos Organometálicos/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antieméticos/uso terapêutico , Ascite/mortalidade , Ascite/patologia , Biomarcadores Tumorais/análise , Neoplasias Ósseas/mortalidade , Cromogranina A/análise , Endoderma/patologia , Feminino , Humanos , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Crista Neural/patologia , Tumores Neuroendócrinos/patologia , Octreotida/efeitos adversos , Octreotida/uso terapêutico , Compostos Organometálicos/efeitos adversos , Intervalo Livre de Progressão , Compostos Radiofarmacêuticos/efeitos adversos , Compostos Radiofarmacêuticos/uso terapêutico , Estudos Retrospectivos
18.
J Tissue Eng ; 12: 20417314211060590, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34868541

RESUMO

In modern life, several factors such as genetics, exposure to toxins, and aging have resulted in significant levels of male infertility, estimated to be approximately 18% worldwide. In response, substantial progress has been made to improve in vitro fertilization treatments (e.g. microsurgical testicular sperm extraction (m-TESE), intra-cytoplasmic sperm injection (ICSI), and round spermatid injection (ROSI)). Mimicking the structure of testicular natural extracellular matrices (ECM) outside of the body is one clear route toward complete in vitro spermatogenesis and male fertility preservation. Here, a new wave of technological innovations is underway applying regenerative medicine strategies to cell-tissue culture on natural or synthetic scaffolds supplemented with bioactive factors. The emergence of advanced bioengineered systems suggests new hope for male fertility preservation through development of functional male germ cells. To date, few studies aimed at in vitro spermatogenesis have resulted in relevant numbers of mature gametes. However, a substantial body of knowledge on conditions that are required to maintain and mature male germ cells in vitro is now in place. This review focuses on advanced bioengineering methods such as microfluidic systems, bio-fabricated scaffolds, and 3D organ culture applied to the germline for fertility preservation through in vitro spermatogenesis.

19.
Sci Adv ; 7(51): eabg4930, 2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34919429

RESUMO

Autonomous experimentation enabled by artificial intelligence offers a new paradigm for accelerating scientific discovery. Nonequilibrium materials synthesis is emblematic of complex, resource-intensive experimentation whose acceleration would be a watershed for materials discovery. We demonstrate accelerated exploration of metastable materials through hierarchical autonomous experimentation governed by the Scientific Autonomous Reasoning Agent (SARA). SARA integrates robotic materials synthesis using lateral gradient laser spike annealing and optical characterization along with a hierarchy of AI methods to map out processing phase diagrams. Efficient exploration of the multidimensional parameter space is achieved with nested active learning cycles built upon advanced machine learning models that incorporate the underlying physics of the experiments and end-to-end uncertainty quantification. We demonstrate SARA's performance by autonomously mapping synthesis phase boundaries for the Bi2O3 system, leading to orders-of-magnitude acceleration in the establishment of a synthesis phase diagram that includes conditions for stabilizing δ-Bi2O3 at room temperature, a critical development for electrochemical technologies.

20.
Proc Natl Acad Sci U S A ; 118(30)2021 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-34301873

RESUMO

Nanotechnology enables investigations of single biomacromolecules, but technical challenges have limited the application in liquid biopsies, for example, blood plasma. Nonetheless, tools to characterize single molecular species in such samples represent a significant unmet need with the increasing appreciation of the physiological importance of protein structural changes at nanometer scale. Mannose-binding lectin (MBL) is an oligomeric plasma protein and part of the innate immune system through its ability to activate complement. MBL also serves a role as a scavenger for cellular debris, especially DNA. This may link functions of MBL with several inflammatory diseases in which cell-free DNA now appears to play a role, but mechanistic insight has been lacking. By making nanoparticle tracking analysis possible in human plasma, we now show that superoligomeric structures of MBL form nanoparticles with DNA. These oligomers correlate with disease activity in systemic lupus erythematosus patients. With the direct quantification of the hydrodynamic radius, calculations following the principles of Taylor dispersion in the blood stream connect the size of these complexes to endothelial inflammation, which is among the most important morbidities in lupus. Mechanistic insight from an animal model of lupus supported that DNA-stabilized superoligomers stimulate the formation of germinal center B cells and drive loss of immunological tolerance. The formation involves an inverse relationship between the concentration of MBL superoligomers and antibodies to double-stranded DNA. Our approach implicates the structure of DNA-protein nanoparticulates in the pathobiology of autoimmune diseases.


Assuntos
DNA/química , Lúpus Eritematoso Sistêmico/diagnóstico , Nanopartículas/química , Proteínas/química , Adolescente , Adulto , Animais , Linfócitos B , Biomarcadores , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Humanos , Inflamação/metabolismo , Inflamação/patologia , Lectina de Ligação a Manose , Camundongos , Camundongos Endogâmicos C57BL , Ligação Proteica , Adulto Jovem
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