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1.
Sci Rep ; 14(1): 10435, 2024 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714737

RESUMO

During takeoff and landing, birds bounce and grab with their legs and feet. In this paper,the lower limb structure of the bionic bird is designed with reference to the function of jumping and grasping, and the PID algorithm based on the development module of stm32 development board is used to speed control the lower limb driving element, so that the motor and the bishaft steering gear move with the rate change of sine wave. According to the speed of grasping response time and the size of grasping force, the structure of the bionic bird paw is designed. Based on the photosensitive sensor fixed in the geometric center of the foot, the grasping action of the lower limb mechanism is intelligently controlled. Finally, the kinematic verification of the lower limb structure is carried out by ADAMS. Experiments show that the foot structure with four toes and three toes is more conducive to maintaining the stability of the body while realizing the fast grasping function. In addition, it can effectively improve the push-lift ratio of the bionic ornithopter by adjusting the sinusoidal waveform rate of the motor speed.


Assuntos
Biônica , Aves , Animais , Aves/fisiologia , Fenômenos Biomecânicos , Algoritmos , Desenho de Equipamento , Voo Animal/fisiologia
2.
Bioanalysis ; 16(7): 77-119, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38389403

RESUMO

The 17th Workshop on Recent Issues in Bioanalysis (17th WRIB) took place in Orlando, FL, USA on June 19-23, 2023. Over 1000 professionals representing pharma/biotech companies, CROs, and multiple regulatory agencies convened to actively discuss the most current topics of interest in bioanalysis. The 17th WRIB included 3 Main Workshops and 7 Specialized Workshops that together spanned 1 week to allow an exhaustive and thorough coverage of all major issues in bioanalysis of biomarkers, immunogenicity, gene therapy, cell therapy and vaccines. Moreover, in-depth workshops on "EU IVDR 2017/746 Implementation and impact for the Global Biomarker Community: How to Comply with these NEW Regulations" and on "US FDA/OSIS Remote Regulatory Assessments (RRAs)" were the special features of the 17th edition. As in previous years, WRIB continued to gather a wide diversity of international, industry opinion leaders and regulatory authority experts working on both small and large molecules as well as gene, cell therapies and vaccines to facilitate sharing and discussions focused on improving quality, increasing regulatory compliance, and achieving scientific excellence on bioanalytical issues. This 2023 White Paper encompasses recommendations emerging from the extensive discussions held during the workshop and is aimed to provide the bioanalytical community with key information and practical solutions on topics and issues addressed, in an effort to enable advances in scientific excellence, improved quality and better regulatory compliance. Due to its length, the 2023 edition of this comprehensive White Paper has been divided into three parts for editorial reasons. This publication (Part 3) covers the recommendations on Gene Therapy, Cell therapy, Vaccines and Biotherapeutics Immunogenicity. Part 1A (Mass Spectrometry Assays and Regulated Bioanalysis/BMV), P1B (Regulatory Inputs) and Part 2 (Biomarkers, IVD/CDx, LBA and Cell-Based Assays) are published in volume 16 of Bioanalysis, issues 8 and 9 (2024), respectively.


Assuntos
Bioensaio , Tecnologia , Bioensaio/métodos , Biomarcadores/análise , Terapia Baseada em Transplante de Células e Tecidos , Imunoterapia Ativa
3.
Clin Cancer Res ; 29(10): 1869-1878, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-36826995

RESUMO

PURPOSE: Proliferation of T-follicular helper (TFH) CD4+ T cells is a postulated pathogenic mechanism for T-cell non-Hodgkin lymphomas (T-NHL). The inducible T-cell costimulator (ICOS) is highly expressed by TFH, representing a potential target. MEDI-570 is a monoclonal antibody against ICOS, which eliminates ICOS+ cells in preclinical models. PATIENTS AND METHODS: We report the safety, pharmacokinetics (PK), pharmacodynamics (PD), and clinical activity of MEDI-570 in T-NHL. NCI-9930 is a phase I, first-in-human study of MEDI-570 in relapsed/refractory malignant T-NHL known to express ICOS. MEDI-570 was administered intravenously every 3 weeks for up to 12 cycles. Primary endpoints were safety, dose-limiting toxicities (DLT), and recommended phase II dose (RP2D). Secondary and exploratory endpoints included efficacy parameters and various correlative studies. This study is supported by the National Cancer Institute (NCT02520791). RESULTS: Twenty-three patients were enrolled and received MEDI-570 at five dose levels (0.01-3 mg/kg). Sixteen (70%) had angioimmunoblastic T-cell lymphoma (AITL); median age was 67 years (29-86) and the median prior lines of therapies was 3 (1-16). Most common grade 3 or 4 adverse events were decreased CD4+ T cells (57%), lymphopenia (22%), anemia (13%), and infusion-related reactions (9%). No DLTs were observed. The RP2D was determined at 3 mg/kg. Analysis of T-cell subsets showed reductions in CD4+ICOS+ T cells reflecting its effects on TFH cells. The response rate in AITL was 44%. CONCLUSIONS: MEDI-570 was well tolerated and showed promising clinical activity in refractory AITL. MEDI-570 resulted in sustained reduction of ICOS+ T lymphocytes.


Assuntos
Linfoma de Células T Periférico , Linfoma de Células T , Humanos , Idoso , Células T Auxiliares Foliculares , Linfócitos T CD4-Positivos , Anticorpos Monoclonais , Fenótipo , Linfoma de Células T/tratamento farmacológico , Linfoma de Células T/patologia , Linfócitos T Auxiliares-Indutores , Linfoma de Células T Periférico/tratamento farmacológico , Linfoma de Células T Periférico/patologia , Proteína Coestimuladora de Linfócitos T Induzíveis
4.
Math Biosci Eng ; 17(6): 7804-7818, 2020 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-33378921

RESUMO

This paper proposes a real-time fire detection framework DeepFireNet that combines fire features and convolutional neural networks, which can be used to detect real-time video collected by monitoring equipment. DeepFireNet takes surveillance device video stream as input. To begin with, based on the static and dynamic characteristics of fire, a large number of non-fire images in the video stream are filtered. In the process, for the fire images in the video stream, the suspected fire area in the image is extracted. Eliminate the influence of light sources, candles and other interference sources to reduce the interference of complex environments on fire detection. Then, the algorithm encodes the extracted region and inputs it into DeepFireNet convolution network, which extracts the depth feature of the image and finally judges whether there is a fire in the image. DeepFireNet network replaces 5×5 convolution kernels in the inception layer with two 3×3 convolution kernels, and only uses three improved inception layers as the core architecture of the network, which effectively reduces the network parameters and significantly reduces the amount of computation. The experimental results show that this method can be applied to many different indoor and outdoor scenes. Besides, the algorithm effectively meets the requirements for the accuracy and real-time of the detection algorithm in the process of real-time video detection. This method has good practicability.

5.
Bioanalysis ; 12(18): 1325-1336, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32946271

RESUMO

Immunogenicity is recognized as a possible clinical risk due to the development of anti drug antibodies (ADAs) that can adversely impact drug safety and efficacy. Although robust assays are currently used to assess the ADA, there is a debate on how best to generate the most appropriate immunogenicity data. There are several factors that can trigger ADA formation including the immunity status of the target population and the severity of the disease indication. Immunogenicity testing has defaulted to the most conservative approach regardless of the inherent risk of the molecule or the patient population. For low-risk biotherapeutics such as human monoclonal antibodies, ADA data that provide clinically relevant information should be prioritized when establishing immunogenicity monitoring plans.


Assuntos
Anticorpos Monoclonais/imunologia , Monitoramento de Medicamentos/métodos , Imunogenética/métodos , Humanos
6.
Lancet Infect Dis ; 18(8): 884-893, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29929783

RESUMO

BACKGROUND: REGN3470-3471-3479 is a co-formulated cocktail of three human monoclonal antibodies targeting three non-overlapping epitopes on Ebola virus. We investigated safety, tolerability, pharmacokinetics, and anti-drug antibodies in healthy adults. METHODS: This randomised, double-blind, placebo-controlled, dose-escalation study was done at a phase 1 unit in the USA. Healthy adults, aged 18-60 years, with a body-mass index of 18·0-30·0 kg/m2 were randomly assigned (3:1) to receive a single intravenous dose of REGN3470-3471-3479 or placebo on day 1 (baseline) in one of the four sequential ascending intravenous dose cohorts (3 mg/kg, 15 mg/kg, 60 mg/kg, and 150 mg/kg). Site investigators and participants were masked to the treatment assignment, whereas designated personnel at the site who prepared and generated the study medication were aware of the randomisation treatment assignments. The primary outcome was safety and the secondary outcomes were the pharmacokinetic profiles and immunogenicity. Study assessments were done the day before study drug administration, on the day of drug administration, on day 2 (before discharge), on days 3, 4, 8, 15, 29, 57, 85, 113, and 141, and at the end of study on day 169. The safety analysis included all randomised participants who received study drug. This trial is registered with ClinicalTrials.gov, number NCT002777151. FINDINGS: Between May 18, 2016, and October 27, 2016, 70 adults were screened and 24 participants were enrolled in the study. 18 participants were assigned to and received REGN3470-3471-3479, and six participants were assigned to and received placebo as a single intravenous infusion. 19 treatment-emergent adverse events occurred in the combined REGN3470-3471-3479 treatment groups, and four treatment-emergent adverse events occurred in combined placebo groups. Adverse events were transient and mild-to-moderate in severity. The most common treatment-emergent adverse event was headache (six [33%] of 18 participants in the combined REGN3470-3471-3479 group vs none of six participants in the placebo group. Headaches were mild-to-moderate in severity, with onset between 2 h and 27 days after start of study drug infusion. There were no deaths, serious adverse events, or adverse events that led to study discontinuation. The pharmacokinetics of each antibody was linear, with mean half-lives of 27·3 days for REGN3471, 21·7 days for REGN3470, and 23·3 days for REGN3479. No participants tested positive for anti-REGN3470, anti-REGN3471, or anti-REGN3479 antibodies. INTERPRETATION: REGN3470-3471-3479 was well tolerated, displayed linear pharmacokinetics, and did not lead to detectable immunogenicity. These data support further clinical development of REGN3470-3471-3479 as a single-dose therapeutic drug for acute Ebola virus infection. FUNDING: The Department of Health and Human Services, the Office of the Assistant Secretary for Preparedness and Response, and the Biomedical Advanced Research and Development Authority.


Assuntos
Administração Intravenosa , Anticorpos Monoclonais/farmacocinética , Glicoproteínas , Voluntários Saudáveis , Doença pelo Vírus Ebola/prevenção & controle , Segurança do Paciente , Adolescente , Adulto , Anticorpos Antivirais/sangue , Método Duplo-Cego , Ebolavirus/isolamento & purificação , Feminino , Cefaleia/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estados Unidos , Adulto Jovem
7.
N Engl J Med ; 377(3): 211-221, 2017 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-28538136

RESUMO

BACKGROUND: Loss-of-function variants in the angiopoietin-like 3 gene (ANGPTL3) have been associated with decreased plasma levels of triglycerides, low-density lipoprotein (LDL) cholesterol, and high-density lipoprotein (HDL) cholesterol. It is not known whether such variants or therapeutic antagonism of ANGPTL3 are associated with a reduced risk of atherosclerotic cardiovascular disease. METHODS: We sequenced the exons of ANGPTL3 in 58,335 participants in the DiscovEHR human genetics study. We performed tests of association for loss-of-function variants in ANGPTL3 with lipid levels and with coronary artery disease in 13,102 case patients and 40,430 controls from the DiscovEHR study, with follow-up studies involving 23,317 case patients and 107,166 controls from four population studies. We also tested the effects of a human monoclonal antibody, evinacumab, against Angptl3 in dyslipidemic mice and against ANGPTL3 in healthy human volunteers with elevated levels of triglycerides or LDL cholesterol. RESULTS: In the DiscovEHR study, participants with heterozygous loss-of-function variants in ANGPTL3 had significantly lower serum levels of triglycerides, HDL cholesterol, and LDL cholesterol than participants without these variants. Loss-of-function variants were found in 0.33% of case patients with coronary artery disease and in 0.45% of controls (adjusted odds ratio, 0.59; 95% confidence interval, 0.41 to 0.85; P=0.004). These results were confirmed in the follow-up studies. In dyslipidemic mice, inhibition of Angptl3 with evinacumab resulted in a greater decrease in atherosclerotic lesion area and necrotic content than a control antibody. In humans, evinacumab caused a dose-dependent placebo-adjusted reduction in fasting triglyceride levels of up to 76% and LDL cholesterol levels of up to 23%. CONCLUSIONS: Genetic and therapeutic antagonism of ANGPTL3 in humans and of Angptl3 in mice was associated with decreased levels of all three major lipid fractions and decreased odds of atherosclerotic cardiovascular disease. (Funded by Regeneron Pharmaceuticals and others; ClinicalTrials.gov number, NCT01749878 .).


Assuntos
Angiopoietinas/antagonistas & inibidores , Anticorpos Monoclonais/administração & dosagem , Aterosclerose/tratamento farmacológico , Doença da Artéria Coronariana/genética , Dislipidemias/tratamento farmacológico , Lipídeos/sangue , Mutação , Idoso , Proteína 3 Semelhante a Angiopoietina , Proteínas Semelhantes a Angiopoietina , Angiopoietinas/genética , Animais , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/farmacologia , Aterosclerose/metabolismo , Doenças Cardiovasculares/prevenção & controle , Doença da Artéria Coronariana/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Método Duplo-Cego , Dislipidemias/sangue , Feminino , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos , Pessoa de Meia-Idade
8.
Bioanalysis ; 7(11): 1325-35, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26110705

RESUMO

BACKGROUND: Pre-analytical factors such as sample processing, handling or storage could affect the stability of biotherapeutics and anti-drug antibodies in clinical samples, potentially impacting the pharmacokinetic and immunogenicity assessments. METHODS: We used sarilumab, a fully human IgG1 monoclonal antibody, and evaluated the stability of sarilumab (both functional and bound forms) and anti-sarilumab antibodies in blood samples during serum collection and the impact of various processing conditions on the analyte stability in serum for long-term storage. We also assessed the incurred sample stability of these analytes in samples from clinical studies. CONCLUSION: Assessment of analyte stability can provide relevant information about sample stability under different pre-analytical conditions and improve the confidence in the validity of bioanalytical data generated.


Assuntos
Anticorpos Monoclonais Humanizados/sangue , Anticorpos Monoclonais Humanizados/imunologia , Anticorpos/imunologia , Animais , Anticorpos Monoclonais Humanizados/metabolismo , Preservação de Sangue/métodos , Coleta de Amostras Sanguíneas/métodos , Estabilidade de Medicamentos , Feminino , Humanos , Imunoensaio/métodos , Medições Luminescentes/métodos , Masculino , Estabilidade Proteica , Soro/imunologia , Soro/metabolismo
9.
J Lipids ; 2014: 140723, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25136459

RESUMO

The purpose of the present report was to examine whether proprotein convertase subtilisin/kexin type 9 (PCSK9) levels differ in individuals who do not exhibit expected reductions in low density lipoprotein cholesterol (LDL-C) with statin therapy. Eighteen nonresponder subjects treated with 80 mg atorvastatin treatment for 6 months without substantial reductions in LDL-C (ΔLDL-C: 2.6 ± 11.4%) were compared to age- and gender-matched atorvastatin responders (ΔLDL-C: 50.7 ± 8.5%) and placebo-treated subjects (ΔLDL-C: 9.9 ± 21.5%). Free PCSK9 was marginally higher in nonresponders at baseline (P = 0.07) and significantly higher in atorvastatin responders after 6 months of treatment (P = 0.04). The change in free PCSK9 over 6 months with statin treatment was higher (P < 0.01) in atorvastatin responders (134.2 ± 131.5 ng/mL post- versus prestudy) than in either the nonresponders (39.9 ± 87.8 ng/mL) or placebo subjects (27.8 ± 97.6 ng/mL). Drug compliance was not lower in the nonresponders as assessed by pill counts and poststudy plasma atorvastatin levels. Serum PCSK9 levels, both at baseline and in response to statin therapy, may differentiate individuals who do versus those who do not respond to statin treatment.

10.
J Biomed Biotechnol ; 2003(5): 299-307, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14688416

RESUMO

Protein microarray-based approaches are increasingly being used in research and clinical applications to either profile the expression of proteins or screen molecular interactions. The development of high-throughput, sensitive, convenient, and cost-effective formats for detecting proteins is a necessity for the effective advancement of understanding disease processes. In this paper, we describe the generation of highly multiplexed, antibody-based, specific, and sensitive protein microarrays coupled with rolling-circle signal amplification (RCA) technology. A total of 150 cytokines were simultaneously detected in an RCA sandwich immunoassay format. Greater than half of these proteins have detection sensitivities in the pg/ml range. The validation of antibody microarray with human serum indicated that RCA-based protein microarrays are a powerful tool for high-throughput analysis of protein expression and molecular diagnostics.

11.
Biochemistry ; 42(50): 14774-84, 2003 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-14674751

RESUMO

The interaction between bovine cytochrome b(5) (cyt b(5)) and horse heart cytochrome c (cyt c) is investigated by NMR spectroscopy. Chemical shifts of cyt b(5) backbone resonances and side chain methyl resonances were monitored as a function of cyt c concentration. The shifts are small but saturatable and indicate that the binding of cyt b(5) with cyt c is in fast exchange. An equilibrium association constant of (6 +/- 3) x 10(4) M(-1) was obtained with a lower limit of 180 s(-1) for the dissociation rate of the complex. To resolve considerable ambiguities in the interpretation of the chemical shift mapping, (15)N relaxation experiments and cross-saturation experiments were used as alternative methods to map the cyt b(5)-cyt c binding interface. Results from the three experiments combined demonstrate that the conserved negatively charged region of cyt b(5) surrounding the solvent-exposed heme edge is involved in the interaction with cyt c. These data support the models proposed by Salemme and Mauk [(1976) J. Mol. Biol. 102, 563-568; (1993) Biochemistry 32, 6613-6623].


Assuntos
Citocromos b5/química , Citocromos c/química , Mapeamento de Peptídeos/métodos , Animais , Sítios de Ligação , Isótopos de Carbono/química , Bovinos , Sequência Conservada , Cavalos , Modelos Químicos , Modelos Moleculares , Isótopos de Nitrogênio/química , Ressonância Magnética Nuclear Biomolecular , Ligação Proteica , Conformação Proteica , Propriedades de Superfície , Termodinâmica
12.
Nat Biotechnol ; 20(4): 359-65, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11923841

RESUMO

Fluorescent-sandwich immunoassays on microarrays hold appeal for proteomics studies, because equipment and antibodies are readily available, and assays are simple, scalable, and reproducible. The achievement of adequate sensitivity and specificity, however, requires a general method of immunoassay amplification. We describe coupling of isothermal rolling-circle amplification (RCA) to universal antibodies for this purpose. A total of 75 cytokines were measured simultaneously on glass arrays with signal amplification by RCA with high specificity, femtomolar sensitivity, 3 log quantitative range, and economy of sample consumption. A 51-feature RCA cytokine glass array was used to measure secretion from human dendritic cells (DCs) induced by lipopolysaccharide (LPS) or tumor necrosis factor-alpha (TNF-alpha). As expected, LPS induced rapid secretion of inflammatory cytokines such as macrophage inflammatory protein (MIP)-1beta, interleukin (IL)-8, and interferon-inducible protein (IP)-10. We found that eotaxin-2 and I-309 were induced by LPS; in addition, macrophage-derived chemokine (MDC), thymus and activation-regulated chemokine (TARC), soluble interleukin 6 receptor (sIL-6R), and soluble tumor necrosis factor receptor I (sTNF-RI) were induced by TNF-alpha treatment. Because microarrays can accommodate approximately 1,000 sandwich immunoassays of this type, a relatively small number of RCA microarrays seem to offer a tractable approach for proteomic surveys.


Assuntos
Citocinas/biossíntese , Citocinas/imunologia , Replicação do DNA , Perfilação da Expressão Gênica/métodos , Imunoensaio/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Anticorpos/imunologia , Linhagem Celular , Citocinas/genética , DNA Circular/biossíntese , DNA Circular/genética , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Humanos , Lipopolissacarídeos/farmacologia , Reação em Cadeia da Polimerase , Proteoma/biossíntese , Proteoma/genética , Proteoma/imunologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sensibilidade e Especificidade , Fator de Necrose Tumoral alfa/farmacologia
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