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1.
Molecules ; 28(2)2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36677619

RESUMO

Thirty novel diamide compounds combining pyrazolyl and polyfluoro-substituted phenyl groups into alanine or 2-aminobutyric acid skeletons were designed and synthesized with pyflubumide as the lead compound to develop potent and environmentally friendly pesticides. The preliminary bioassay results indicated that the new compounds containing the para-hexa/heptafluoroisopropylphenyl moiety exhibit fungicidal, insecticidal, and acaricidal activities. This is the first time that the para-hexa/heptafluoroisopropylphenyl group is a key fragment of the fungicidal activity of new N-phenyl amide compounds. Most of the target compounds exhibited moderate to good insecticidal activity against Aphis craccivora at a concentration of 400 µg/mL, and some showed moderate activity at a concentration of 200 µg/mL; in particular, compounds I-4, II-a-10, and III-26 displayed higher than 78% lethal rates at 200 µg/mL. Compound II-a-14 exhibited a 61.1% inhibition at 200 µg/mL for Tetranychus cinnabarinus. In addition, some of the target compounds exhibited good insecticidal activities against Plutella xylostella at a concentration of 200 µg/mL; the mortalities of compounds I-1, and II-a-15 were 76.7% and 70.0%, respectively. Preliminary analysis of the structure-activity relationship (SAR) indicated that the insecticidal and acaricidal activities varied significantly depending on the type of substituent and substitution pattern. The fungicidal activity results showed that compounds I-1, II-a-10, II-a-17, and III-26 exhibited good antifungal effects. Enzymatic activity experiments and in vivo efficacy of compound II-a-10 were conducted and discussed.


Assuntos
Acaricidas , Fungicidas Industriais , Inseticidas , Mariposas , Animais , Inseticidas/farmacologia , Diamida/farmacologia , Alanina/farmacologia , Desenho de Fármacos , Relação Estrutura-Atividade , Fungicidas Industriais/farmacologia , Estrutura Molecular
2.
Diabet Med ; 39(5): e14785, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34989030

RESUMO

INTRODUCTION: C-peptide is an important marker to assess residual insulin production in individuals with type 1 diabetes (T1D). The accuracy and detection limits of C-peptide assays are important to detect C-peptide microsecretion and to reliably observe changes over time in these people. We compared and verified two commercially available assays able to measure C-peptide in the picomolar range. METHODS: The ultrasensitive Mercodia enzyme-linked immunosorbent C-peptide assay (ELISA) was compared with the Beckman immunoradiometric assay (IRMA) for C-peptide, assessing reproducibility (coefficient of variation [CV]), limit of blank (LoB), limit of detection (LoD) and limit of quantitation (LoQ). RESULTS: For both assays within-run and between-run variation were high at the low (around the detection limit) C-peptide concentration range, with CVs of around 40%. LoB values for the ultrasensitive ELISA and the IRMA were 1.3 and 0.16 pmol/L respectively. LoD values were 2.4 and 0.54 pmol/L respectively. LoQ values were 9.7 and 3.8 pmol/L respectively. Only the IRMA met the specifications claimed by the manufacturer. CONCLUSIONS: The IRMA provided the lowest threshold for quantification of serum C-peptide. LoQ of commercially available assays should be established in-house before applying them in research studies and clinical trials in which low C-peptide levels have clinical or scientific relevance.


Assuntos
Diabetes Mellitus Tipo 1 , Bioensaio , Peptídeo C , Diabetes Mellitus Tipo 1/diagnóstico , Ensaio de Imunoadsorção Enzimática , Humanos , Insulina , Reprodutibilidade dos Testes
3.
J Clin Lab Anal ; 36(4): e24294, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35274775

RESUMO

INTRODUCTION: We conducted a multicenter evaluation of a new one-stage factor VIII (FVIII) assay (Roche Diagnostics), intended for the quantitative assessment of FVIII activity. We evaluated the analytical performance of the FVIII assay on the cobas t 711 analyzer. METHODS: Experiments performed at three laboratories used 3.2% citrated residual or commercially purchased plasma samples. Five human plasma pools and two controls were used to determine assay within-run and within-laboratory precision, and total reproducibility; coefficients of variation (CVs) and/or standard deviations (SDs) were calculated. Lot-to-lot variability and method comparison (vs Coagulation FVIII Deficient Plasma/Dade Actin FS Activated PTT reagent/Standard Human Plasma Calibrator on the Sysmex CS-5100 analyzer; Siemens Healthineers) were evaluated by Passing-Bablok and Deming regression, respectively, and Pearson's r calculated. Assay-specific reference range was determined using 199 fresh plasma samples from healthy adults, not receiving anticoagulants. RESULTS: Across sites, SDs for repeatability were 0.016-0.046 for samples with ≤1.0 international units (IU)/dL FVIII activity; CVs were 0.9%-3.8% for samples with >1.0 IU/dl activity. Among samples with mean FVIII activity 0.344-133 IU/dl, good intermediate precision (SD 0.020 for samples with 0.344 IU/dl activity; CV 1.8%-4.7%) and good total reproducibility (CV 2.0%-13.3%) were observed. The FVIII assay showed excellent lot-to-lot variability (Pearson's r = .999) and good correlation with the comparator assay (Pearson's r = .993-.996). The reference range for FVIII activity was 82.2-218.0 IU/dl. CONCLUSION: The one-stage FVIII assay demonstrated robust analytical performance on the cobas t 711 analyzer, supporting its use in routine laboratory practice.


Assuntos
Fator VIII , Hemofilia A , Adulto , Testes de Coagulação Sanguínea , Hemofilia A/diagnóstico , Humanos , Valores de Referência , Reprodutibilidade dos Testes
4.
Medicina (Kaunas) ; 58(2)2022 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-35208638

RESUMO

Background and Objectives: Three-dimensional (3D) metallic trabecular structures made by additive manufacturing (AM) technologies promote new bone formation and osteointegration. Surface modifications by chemical treatments can improve the osteoconductive properties of metallic structures. An in vivo study in sheep was conducted to assess the bone response to randomized trabecular titanium structures that underwent a surface modification by chemical treatment compared to the bone response to the untreated specimens. Material and Methods: Sixteen specimens with a randomized trabecular titanium structure were implanted in the spongious bone of the distal femur and proximal tibia and the cortical bone of the tibial diaphysis of two sheep. Of them, eight implants had undergone a chemical treatment (treated) and were compared to eight implants with the same structure but native surfaces (native). The sheep were sacrificed at 6 weeks. Surface features of the lattice structures (native and treated) were analyzed using a 3D non-contact profilometer. Compression tests of 18 lattice cubes were performed to investigate the mechanical properties of the two structures. Excellent biocompatibility for the trabecular structures was demonstrated in vitro using a cell mouse fibroblast culture. Histomorphometric analysis was performed to evaluate bone implant contact and bone ingrowth. Results: A compression test of lattice cubic specimens revealed a comparable maximum compressive strength value between the two tested groups (5099 N for native surfaces; 5558 N for treated surfaces; p > 0.05). Compared to native surfaces, a homogenous formation of micropores was observed on the surface of most trabeculae that increased the surface roughness of the treated specimens (4.3 versus 3.2 µm). The cellular viability of cells seeded on three-dimensional structure surfaces increased over time compared to that on plastic surfaces. The histomorphometric data revealed a similar behavior and response in spongious and cortical bone formation. The percentage of the implant surface in direct contact with the regenerated bone matrix (BIC) was not significantly different between the two groups either in the spongious bone (BIC: 27% for treated specimens versus 30% for native samples) or in the cortical bone (BIC: 75% for treated specimens versus 77% for native samples). Conclusions: The results of this study reveal rapid osseointegration and excellent biocompatibility for the trabecular structure regardless of surface treatment using AM technologies. The application of implant surfaces can be optimized to achieve a strong press-fit and stability, overcoming the demand for additional chemical surface treatments.


Assuntos
Osseointegração , Titânio , Animais , Regeneração Óssea , Fêmur/cirurgia , Camundongos , Osseointegração/fisiologia , Ovinos , Propriedades de Superfície
5.
Haemophilia ; 27(6): e704-e712, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34590394

RESUMO

INTRODUCTION: Recombinant coagulation factor VIII (FVIII) products are the standard of care for patients with haemophilia A. The development of modified FVIII products has provided benefit for patients but presented challenges for monitoring FVIII activity. AIM: This single-centre study evaluated the Roche FVIII one-stage clotting assay (OSA) in measuring FVIII activity in plasma samples spiked with seven FVIII products at clinically relevant concentrations. METHODS: FVIII-deficient plasma samples were spiked with two batches of recombinant FVIII products (octocog alfa, moroctocog alfa, simoctocog alfa, efmoroctocog alfa, damoctocog alfa pegol, rurioctocog alfa pegol, lonoctocog alfa) at 1-120 IU/dL FVIII activity, according to their labelled potency. Measurement was conducted on the cobas t 511/711 analysers using the Roche FVIII OSA and the Technoclone TECHNOCHROM FVIII:C chromogenic substrate assay (CSA). RESULTS: Using the OSA, FVIII activity was close to labelled potency for most analysed FVIII products including a recombinant FVIII Fc fusion protein. PEGylated FVIII product, damoctocog alfa pegol, was marginally above and single-chain product, lonoctocog alfa, below the predefined acceptance criteria: for FVIII activity < 25 IU/dL: ± 5 IU/dL; for FVIII activity ≥ 25 IU/dL: ± 20% (relative). The different principles of OSA and CSA led to discrepancies in the estimation of all analysed FVIII products. Additionally, in vitro recovery was increased at lower levels of FVIII activity using the OSA, whereas recovery was more consistent using the CSA. CONCLUSION: These data allow the interpretation of FVIII activity results for different FVIII products using the Roche FVIII OSA on the cobas t 511/711 analysers.


Assuntos
Hemofilia A , Hemostáticos , Testes de Coagulação Sanguínea , Fator VIII , Hemofilia A/tratamento farmacológico , Humanos
6.
J Mol Recognit ; 33(11): e2871, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32677119

RESUMO

A novel folic acid functionalized terbium-doped dendritic fibrous nanoparticle (Tb@KCC-1-NH2 -FA) with high surface area was synthesized using a novel hydrothermal protocol. In the present work, we report the fluorescent Tb-doted nanomaterial with emission wavelength at 497 nm which confirms the formation of Tb@KCC-1-NH2 -FA. Synthesized nanoparticles were investigated through transmission electron microscope, field emission scanning electron Microscopy, Fourier transform infrared spectra, Brunauer-Emmett-Teller, energy dispersive X-ray, Zeta potential and particle size distribution values and AFM (Atomic force microscopy) techniques. Specially, our desired nanomaterial which has FA moieties on the surface of Tb@KCC-1-NH2-FA where interact with folate receptor (FR) which there is on the surface of the various cancer cells. For this purpose, fluorescence microscopy images were used to prove the uptake of FA based nanomaterial with FR-positive MDA breast cancer and HT 29 colon cancer cells. Also HEK 293 normal cells as FR-negative cells verified the specificity of our desired nanomaterial toward the FR-positive cells. The cytotoxicity survey of Tb@KCC-1-NH2 -FA was examined by MTT assays against MDA breast cancer, HT 29 colon cancer and HEK 293 Normal cell lines which confirmed their biocompatible nature with any significant cytotoxic effects even for concentration higher than 900 µg/mL which could be used as a non-toxic catalyst or carrier in biological ambient. Hence, Tb@KCC-1-NH2 -FA were synthesized using green and hydrothermal method; the process was simple with good productivity and desired nanocomposite was non-toxic.


Assuntos
Técnicas Biossensoriais , Ácido Fólico/farmacologia , Nanopartículas/química , Térbio/farmacologia , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Neoplasias da Mama/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/tratamento farmacológico , Feminino , Receptor 1 de Folato/genética , Ácido Fólico/química , Células HEK293 , Células HT29 , Humanos , Microscopia de Fluorescência , Dióxido de Silício/química , Dióxido de Silício/farmacologia , Térbio/química
7.
Mol Pharm ; 17(3): 919-932, 2020 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-31986050

RESUMO

The 1:1 cocrystal of the antifungal agent ketoconazole with p-aminobenzoic acid was successfully crystallized and systematically characterized by a physical and pharmacological point of view. Crystal structure determination confirmed the cocrystal identity, giving full insight in its crystal packing and degree of disorder. Powder dissolution measurements revealed a 10-fold aqueous solubility increase that induces a 6.7-fold oral bioavailability improvement compared to ketoconazole. In vitro cell assays showed a good toxicity profile of the cocrystal with lower oxidative stress and inflammation and enhanced antifungal activity against several Candida species. The in vivo study of the cocrystal indicated similar pharmacokinetic profiles and liver toxicity with increased transaminases, as reported for ketoconazole. Notably, besides minor signs of inflammation, no morphological changes in liver parenchyma or signs of fibrosis and necrosis were detected. The enhanced solubility and oral bioavailability of the cocrystal over ketoconazole, together with the improved antifungal activity and good in vitro/in vivo toxicity, indicate its potential use as an alternative antifungal agent to the parent drug. Our results bring evidence of cocrystallization as a successful approach for bioavailability improvement of poorly soluble drugs.


Assuntos
Ácido 4-Aminobenzoico/química , Antifúngicos/química , Composição de Medicamentos/métodos , Cetoconazol/química , Ácido 4-Aminobenzoico/administração & dosagem , Ácido 4-Aminobenzoico/farmacocinética , Administração Oral , Animais , Antifúngicos/administração & dosagem , Antifúngicos/farmacocinética , Disponibilidade Biológica , Candida/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cristalização , Combinação de Medicamentos , Estabilidade de Medicamentos , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Cetoconazol/administração & dosagem , Cetoconazol/farmacocinética , Ratos , Solubilidade , Testes de Toxicidade Aguda , Água/química
8.
Int J Legal Med ; 133(2): 365-372, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30191314

RESUMO

We present a novel multiplex assay for the simultaneous detection of 12 polymorphisms within the UGT1A9 sequence, which codes for enzymes involved in phase II biotransformation. The assay combines a multiplexed amplification step with single-base extension sequencing. The method described here is fast, cost-effective, and easy-to-use, combining the relevant features of screening methods for research and diagnostics in pharmacogenetics. To validate the assay, we tested reproducibility and sensitivity and analysed allele frequencies of 110 Caucasian individuals. Furthermore, we describe combining genetic information of individuals consuming Cannabis sativa products with respective plasma concentrations of a metabolite.


Assuntos
Dronabinol/farmacocinética , Glucuronosiltransferase/genética , Variantes Farmacogenômicos/genética , Polimorfismo Genético , Psicotrópicos/farmacocinética , Adolescente , Adulto , Feminino , Toxicologia Forense , Frequência do Gene , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Reprodutibilidade dos Testes , Análise de Sequência , UDP-Glucuronosiltransferase 1A , Adulto Jovem
9.
Drug Chem Toxicol ; 42(4): 343-348, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29199475

RESUMO

Ribavirin is an important component of the treatment for hepatitis C virus (HCV) infection and, in combination with the new direct-acting antiviral (DAA) agents, comprises the major current therapeutic regimens. This study evaluated the cytotoxicity and chromosomal instability induced by ribavirin using the in vitro cytokinesis-block micronucleus cytome (CBMN-Cyt) assay in two cell lines with different expression levels of drug-metabolizing enzymes: human hepatocellular carcinoma cells (HepG2) and Chinese hamster ovary (CHO-K1) cells. HepG2 cells were treated with nine concentrations (from 15.3 µg/ml to 3.9 mg/ml) and CHO-K1 cells were exposed to eight concentrations (from 15.3 µg/ml to 1.9 mg/ml) of ribavirin for 24 h. Ribavirin inhibited cell proliferation in both cell lines, but at different concentrations: 3.9 mg/ml in HepG2 and 244.2 µg/ml in CHO-K1 cells. No significant differences were observed regarding aspects of cell death in HepG2 and CHO-K1 cells, reflecting the absence of cytotoxic effects associated to ribavirin. Ribavirin did not increase the frequency of nucleoplasmic bridges (NPBs) and nuclear bud (NBUD). However, when compared to the negative control, a significant increase in micronuclei (MNi) frequency was observed in both cell lines. However, chromosomal instability was induced by higher concentrations of ribavirin in HepG2 cells (from 61.1 to 976.8 µg/ml), compared with CHO-K1 cells (15.3 and 30.5 µg/ml). These results demonstrate the potential of ribavirin to promote chromosomal instability, and suggest that cells with different expressions of drug-metabolizing enzymes show different susceptibility to ribavirin effects.


Assuntos
Antivirais/toxicidade , Proliferação de Células/efeitos dos fármacos , Instabilidade Cromossômica/efeitos dos fármacos , Citocinese/efeitos dos fármacos , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Ribavirina/toxicidade , Animais , Antivirais/metabolismo , Apoptose/efeitos dos fármacos , Células CHO , Cricetulus , Relação Dose-Resposta a Droga , Células Hep G2 , Humanos , Inativação Metabólica , Testes para Micronúcleos , Ribavirina/metabolismo
10.
Int J Mol Sci ; 20(20)2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31623142

RESUMO

The objective of this study was the preparation and physico-chemical, mechanical, biological, and functional characterization of a multifunctional coating for an innovative, fully implantable device. The multifunctional coating was designed to have three fundamental properties: adhesion to device, close mechanical resemblance to human soft tissues, and control of the inflammatory response and tissue repair process. This aim was fulfilled by preparing a multilayered coating based on three components: a hydrophilic primer to allow device adhesion, a poly(vinyl alcohol) hydrogel layer to provide good mechanical compliance with the human tissue, and a layer of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) fibers. The use of biopolymer fibers offered the potential for a long-term interface able to modulate the release of an anti-inflammatory drug (dexamethasone), thus contrasting acute and chronic inflammation response following device implantation. Two copolymers, poly(vinyl acetate-acrylic acid) and poly(vinyl alcohol-acrylic acid), were synthetized and characterized using thermal analysis (DSC, TGA), Fourier transform infrared spectroscopy (FT-IR chemical imaging), in vitro cell viability, and an adhesion test. The resulting hydrogels were biocompatible, biostable, mechanically compatible with soft tissues, and able to incorporate and release the drug. Finally, the multifunctional coating showed a good adhesion to titanium substrate, no in vitro cytotoxicity, and a prolonged and controlled drug release.


Assuntos
Materiais Revestidos Biocompatíveis/química , Próteses e Implantes , Fenômenos Químicos , Técnicas de Química Sintética , Humanos , Hidrogéis/química , Fenômenos Mecânicos , Termodinâmica
11.
Zhonghua Yi Xue Za Zhi ; 98(44): 3607-3612, 2018 Nov 27.
Artigo em Zh | MEDLINE | ID: mdl-30486579

RESUMO

Objective: To evaluate the performance of MALDI Biotyper system in identification of clinically isolated pathogens so as to provide a new rapid identification method. Methods: Total 21 270 pathogens strains, isolated from the First Affiliated Hospital of Fujian Medical Universityduring Nov. 2015 to Dec. 2016, were identified by VITEK-Ⅱ, API and MALDI Biotyper system, respectively.The isolated strains were confirmed by DNA sequencing. Results: The identification of common bacteria with MALDI Biotyper and phenotypic system is highly consistent (>95% and >90%). Among 43 strains of anaerobic bacteria, MALDI Biotyper could identify 90.7% bacteria to species level and 97.7% bacteria to genus level with the statistical significance(χ(2)=6.76, P<0.01), while phenotypic system only identified 65.1% bacteria to species and 69.8% bacteria to genus. Also, no statistical significance was shown for Trichosporon and Candida(P>0.05). MALDI Biotyper could identify 76% filamentous fungi and all of Actinomycetes, Nocardia, Mycobacterium and Legionella to genus level. Conclusions: MALDI Biotyper is an easy-performed, sensitive method for the identification of clinically isolated pathogens. Additionally, the pretreatment and reference database has the effect on identification.


Assuntos
Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Fungos , Legionella , Mycobacterium , Análise de Sequência de DNA
12.
Curr Cardiol Rep ; 19(8): 69, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28653131

RESUMO

PURPOSE OF REVIEW: Since identification of aspartate aminotransferase as the first cardiac biomarker in the 1950s, there have been a number of new markers used for myocardial damage detection over the decades. There have also been several generations of troponin assays, each with progressively increasing sensitivity for troponin detection. Accordingly, the "standard of care" for myocardial damage detection continues to change. The purpose of this paper is to review the clinical utility, biological mechanisms, and predictive value of these various biomarkers in contemporary clinical studies. RECENT FINDINGS: As of this writing, a fifth "next" generation troponin assay has now been cleared by the US Food and Drug Administration for clinical use in the USA for subjects presenting with suspected acute coronary syndromes. Use of these high-sensitivity assays has allowed for earlier detection of myocardial damage as well as greater negative predictive value for infarction after only one or two serial measurements. Recent algorithms utilizing these assays have allowed for more rapid rule-out of myocardial infarction in emergency department settings. In this review, we discuss novel assays available for the risk assessment of subjects presenting with chest pain, including both the "next generation" cardiac troponin assays as well as other novel biomarkers. We review the biological mechanisms for these markers, and explore the positive and negative predictive value of the assays in clinical studies, where reported. We also discuss the potential use of these new markers within the context of future clinical care in the modern era of higher sensitivity troponin testing. Finally, we discuss advances in new platforms (e.g., mass spectrometry) that historically have not been considered for rapid in vitro diagnostic capabilities, but that are taking a larger role in clinical diagnostics, and whose prognostic value and power promise to usher in new markers with potential for future clinical utility in acute coronary syndrome.


Assuntos
Síndrome Coronariana Aguda/diagnóstico , Troponina/sangue , Síndrome Coronariana Aguda/sangue , Biomarcadores/sangue , Dor no Peito , Diagnóstico Diferencial , Humanos , Infarto do Miocárdio/sangue , Infarto do Miocárdio/diagnóstico , Valor Preditivo dos Testes , Medição de Risco , Sensibilidade e Especificidade
13.
Zhongguo Zhong Yao Za Zhi ; 42(12): 2228-2235, 2017 Jun.
Artigo em Zh | MEDLINE | ID: mdl-28822174

RESUMO

Animal medicine is a unique part of traditional Chinese medicine. They have strong effects, but their effective compounds are not entirely known. The efficiency and safety of animal medicines can't be effectively controlled by current quality assurance system and evaluation method, which has deeply influenced the development of animal medicines. Biological assay does not focus on efficacy of single component, but directly reflects the pharmacodynamics and safety of animal medicines by biological effect. With the development of biotechnology, many new technologies have emerged, such as biochip and high content analysis. Based on the related targets, pathways and key biochemical factors, the field of biological assay has been expanded. With advantages of pharmacology andoverall controllability, as well as the characteristics of in line with the quality control of Chinese Medicine, biological assay will become one of the important development directionsfor quality standardization of animal medicines.


Assuntos
Bioensaio , Materia Medica/normas , Controle de Qualidade , Animais , Medicina Tradicional Chinesa
14.
Biologicals ; 44(3): 150-6, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27017583

RESUMO

The biosimilar versions of recombinant methionyl human granulocyte colony-stimulating factor (rh-Met-G-CSF, filgrastim) are now widely available. Because changes to the formulation often lead to subtle differences, there is a critical need to define techniques to test and insure the quality of these products. The present study was designed to compare formulation and thermal stress stability of filgrastim products. The formulation ingredients including acetate, polysorbate 80, and sorbitol were determined using state-of-the-art validated analytical methods. The formulation pH and osmolality were also measured. Moreover, the stability profiles of 8 filgrastim products using thermal stress at 57 °C for 4 h were assessed by size-exclusion high-performance liquid chromatography (SE-HPLC) and in vitro biological assay. The products had different stability profiles. More stable products were within the specification for formulation and less stable products were beyond the specification limits. Altogether, the results suggest that a short-time stress study at 57 °C and analysis of filgrastim by SE-HPLC could unveil formulation problems and is potentially useful for comparability studies.


Assuntos
Composição de Medicamentos/métodos , Filgrastim/química , Temperatura Alta , Acetatos/análise , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cromatografia em Gel/métodos , Cromatografia Líquida de Alta Pressão/métodos , Estabilidade de Medicamentos , Filgrastim/farmacologia , Fármacos Hematológicos/química , Fármacos Hematológicos/farmacologia , Concentração de Íons de Hidrogênio , Camundongos , Concentração Osmolar , Polissorbatos/análise , Sorbitol/análise , Fatores de Tempo
15.
Gen Comp Endocrinol ; 222: 62-8, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26209865

RESUMO

Although it is known that hormone concentrations vary considerably between individuals within a population, how they change across time and how they relate to an individual's reproductive effort remains poorly quantified in wild animals. Using faecal samples collected from wild red deer stags, we examined sources of variation in faecal cortisol and androgen metabolites, and the potential relationship that these might have with an index of reproductive effort. We also biologically validated an assay for measuring androgen metabolites in red deer faeces. We show that variation in hormone concentrations between samples can be accounted for by the age of the individual and the season when the sample was collected. Faecal cortisol (but not androgen) metabolites also showed significant among-individual variation across the 10-year sampling time period, which accounted for 20% of the trait's phenotypic variance after correcting for the age and season effects. Finally, we show that an index of male reproductive effort (cumulative harem size) during the mating season (rut) was positively correlated with male cortisol concentrations, both among and within individuals. We suggest that the highest ranking males have the largest cumulative harem sizes (i.e. invest the greatest reproductive effort), and that this social dominance may have associated behaviours such as increased frequency of agonistic interactions which are associated with corresponding high levels of faecal cortisol metabolites (FCM).


Assuntos
Androgênios/química , Hidrocortisona/metabolismo , Testosterona/metabolismo , Animais , Bioensaio , Cervos , Masculino , Reprodução
16.
Anal Biochem ; 463: 75-81, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23851341

RESUMO

The SNARE super family has three core members, namely SNAP-25, VAMP-2, and syntaxin. SNAP-25 is cleaved by botulinum toxins (BoNTs)/A, /C, and /E, whereas VAMP-2 is the substrate for proteolytic BoNTs/B, /D, /F, and /G. In this study, we constructed a hybrid gene encoding the fusion protein SNVP that encompasses SNAP-25 residues Met1 to Gly206 and VAMP-2 residues Met1 to Lys94. The hybrid gene was cloned in a prokaryotic vector carrying an N-terminal pelB signal sequence and overexpressed in Escherichia coli BL21(DE3) Rosetta. To easily purify the protein, 6× His double-affinity tags were designed as the linker and C terminus of the fusion protein. SNVP was purified to homogeneity by affinity chromatography on a HisTrap FF column and determined to be more than 97% pure by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. N-terminal sequencing of the purified protein showed that signal peptide was successfully removed. The fusion protein SNVP contained the protease cleavage sites of all seven serotypes of BoNTs. SNVP was also proved to be recognized and cleaved by the endopeptidase of BoNTs (BoNT/A-LC, BoNT/B-LC, BoNT/E-LC, and BoNT/G-LC). The novel fusion substrate SNVP exhibited high biological activity under the optimal conditions, suggesting its potential use as a reagent for BoNT assay.


Assuntos
Toxinas Botulínicas/análise , Eletroforese em Gel de Poliacrilamida , Proteína 25 Associada a Sinaptossoma/metabolismo , Bioensaio , Toxinas Botulínicas/metabolismo , Cinética , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Especificidade por Substrato , Proteína 25 Associada a Sinaptossoma/genética , Proteína 2 Associada à Membrana da Vesícula/genética , Proteína 2 Associada à Membrana da Vesícula/metabolismo
17.
Ceska Gynekol ; 79(4): 295-304, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25398151

RESUMO

OBJECTIVE: To compare the chronic effects of antiretrovirals (lamivudine, stavudine, delavirdine, nelfinavir, amprenavir and an association of lopinavir/ritonavir) on albino pregnant rats. DESIGN: Review. SETTING: Department of Obstetrics, Federal University of São Paulo (UNIFESP), São Paulo, SP, Brazil. METHODS: This was a comparative retrospective study formed by 18 groups of 10 pregnant rats each, which were nearly three months of age and weighed 200 g. All of them were medicated every day using a stomach probe, while the control group was given 1 mL of distilled water. The study groups received lamivudine (at 5, 15 and 45 mg/kg/day); stavudine (at 1, 3 and 9 mg/kg/day); nelfinavir (at 40, 120 and 360 mg/kg/day); amprenavir (at 46, 138 and 414 mg/kg/day); lopinavir/ritonavir (at 12.8/3.2, 38.4/9.6 and 115/28.8 mg/kg/day) and delavirdine (at 20 and 60 mg/kg/day). These represented 1, 3 and 9 times the human therapeutic dose, except for the last drug, for which the 9-times dose was not used. Maternal, litter and placental weights, implantation and reabsorption numbers, major external fetal malformations and fetal and maternal deaths were evaluated. The Kruskal-Wallis test was used to compare quantitative variables and the chi-square test was used to compare qualitative variables. RESULTS: At all three doses, stavudine increased the maternal weight (p=0.001), while lamivudine at 3- and 9-times doses reduced it (p<0.001). Amprenavir at all of the doses, and lopinavir/ritonavir at 3- and 9-times doses, caused higher rates of maternal death (p<0.001). Regarding the fetuses, none of the antiretroviral drugs studied were harmful with regard to implantation, reabsorption, teratogenity and mortality (p>0.05). Stavudine at all doses reduced the litter weights (p<0.001); however, lamivudine at the usual and 3-times doses, delavirdine at 3-times dose, and amprenavir at 3-times dose increased the litter weight (p<0.001). CONCLUSION: In the maternal compartment, we observed lethal toxicity in the pregnant rats that received amprenavir and ritonavir/lopinavir; and maternal weight change with lamivudine and stavudine. In the fetal compartment, adverse effects were observed in relation to litter weight from stavudine, lamivudine, delavirdine and amprenavir.

18.
Environ Sci Pollut Res Int ; 31(13): 19206-19225, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38355858

RESUMO

Toxicological effects of silver nanoparticles (SNPs) in different organisms have been studied; however, interactions of SNPs with other environmental pollutants such as mercury are poorly understood. Herein, bioassay tests were performed according to ΟECD 201 guideline to assess the toxic effects induced by mercury ions (mercury chloride, MCl) on the marine microalga Chaetoceros muelleri in the presence of SNPs or silver ions (silver nitrate, SN). Acute toxicity tests displayed that the presence of SNPs or SN (0.01 mg L-1) significantly reduced the toxicity of MCl (0.001, 0.01, 0.1, 1, 10, and 100 mg L-1) and increased the IC50 of MCl from 0.072 ± 0.014 to 0.381 ± 0.029 and 0.676 ± 0.034 mg L-1, respectively. In the presence of SN or SNPs, the mercury-reducing effect on algal population growth significantly decreased. Considering the increase of IC50, the mercury toxicity decreased approximately 5.44 and 9.66 times in the presence of SNPs or SN, respectively. The chlorophyll a and c contents decreased at all exposures; however, the decrease by MCl-SNPs and MCl-SN was significantly less than MCl except at 1 mg L-1. The lowering effect of MCl-SN on chlorophyll contents was less than MCl and MCl-SNPs. MCl exposure induced significant raises in total protein content (TPC) at concentrations < 0.01mg  L-1, with a maximum of ~ 70.83% attained at 100 mg L-1. The effects of MCl-SNPs and MCl-SN on TPC were significantly less than MCl. Total lipid content (TLC) at all MCl concentrations was higher than the control, while at coexposure to MCl-SN, TLC did not change until 0.01 mg L-1 compared with the control. The effects of MCl-SN and MCL-SNPs on TPC and TLC were in line with toxicity results, and were significantly less than those of MCl individually, confirming their antagonistic effects on MCl. The morphological changes of algal cells and mercury content of the cell wall at MCl-SN and MCl-SNPs were mitigated compared with MCl exposure. These findings highlight the mitigatory impacts of silver species on mercury toxicity, emphasizing the need for better realizing the mixture toxicity effects of pollutants in the water ecosystem.


Assuntos
Poluentes Ambientais , Mercúrio , Nanopartículas Metálicas , Microalgas , Poluentes Químicos da Água , Mercúrio/toxicidade , Clorofila A/metabolismo , Microalgas/metabolismo , Nanopartículas Metálicas/toxicidade , Ecossistema , Prata/toxicidade , Poluentes Ambientais/toxicidade , Íons , Poluentes Químicos da Água/toxicidade
19.
J Clin Neurol ; 20(1): 46-49, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38179631

RESUMO

BACKGROUND AND PURPOSE: Neurofilament light chain (NfL) levels serve as a marker of neuroaxonal injury and can be measured in both cerebrospinal fluid and serum. Although serum NfL (sNfL) levels have been shown to increase with the progression of various neurological conditions, normative values for healthy individuals have not yet been established. This study was undertaken to determine age-specific normative values for sNfL and evaluate the associations between sNfL and sociodemographic characteristics. METHODS: A retrospective analysis was conducted using population-based data collected by the National Health and Nutrition Examination Survey between 2013 and 2014. The sera of 2071 adult participants were collected. General linear models were used to examine the associations between sNfL levels and sample characteristics. RESULTS: The data analysis revealed a significant positive association between age and sNfL levels (p<0.001). Sex was also associated with sNfL levels (p=0.04) after controlling for age. The mean sNfL levels for males and females were 17.99 pg/mL (95% confidence interval [CI]=15.43-20.17) and 15.78 pg/mL (95% CI=13.00-18.55) respectively, after controlling for age. CONCLUSIONS: These results suggest that sNfL levels increase with age and are affected by sex. The findings of this study provide a useful baseline for comparing sNfL levels in clinical practice and future research.

20.
Eur Urol Open Sci ; 62: 131-139, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38496820

RESUMO

Background: Patients with muscle-invasive bladder cancer (MIBC) who receive radiotherapy with curative intent are followed by imaging, cystoscopy, and urine cytology. However, interpretation of cytology and cystoscopy is hampered by the impact of ionizing radiation on cells. Objective: To assess the diagnostic performance of a genomic urine assay to detect urinary tract recurrences in patients with MIBC treated by (chemo)radiation. Design setting and participants: Patients with nonmetastatic MIBC who underwent (chemo)radiation with curative intent from 2016 to 2020 were prospectively included. Follow-up consisted of cystoscopy and upper tract imaging. Prior to cystoscopy, a urine sample was analyzed to assess mutations in the genes FGFR3, HRAS, and TERT and methylation of OTX1, TWIST1, and ONECUT2. The treating physician was blinded for the assay result. Outcome measurements and statistical analysis: The primary endpoint was a urinary tract recurrence. Cross-sectional sensitivity, specificity, and negative predictive value (NPV) were analyzed using a previously developed logistic regression model for the detection of bladder cancer with this assay. The secondary endpoint was the risk of a future urinary tract recurrence following a positive test and negative cystoscopy/imaging, using a time-dependent Cox proportional hazard analysis. Results and limitations: A total of 143 patients were included, and 503 urine samples were analyzed. The median study duration was 20 mo (interquartile range [IQR] 10-33), and the median time to a recurrence was 16 mo (IQR 12-26). In 27 patients, 32 urinary tract recurrences were diagnosed, including three upper tract tumors. Of 32 recurrences, 18 (56%) had a concomitant urine test available. The diagnostic model had an area under the curve of 0.80 (95% confidence interval [CI] 0.69-0.90) with corresponding sensitivity, specificity, and NPV of 78 (95% CI 52-94), 77% (95% CI 73-81), and 99% (95% CI 97-100). When taking into account the anticipatory effect of the test, 28/32 (88%) recurrences were detected. A Cox regression analysis showed a hazard ratio of 14.8 for the development of a future recurrence (p < 0.001). A major limitation was the lack of a concomitant urine test result in 14/32 (44%) recurrences. Conclusions: A genomic urine assay detected urinary tract recurrences after (chemo)radiation in patients with MIBC, and a positive test was strongly associated with future recurrences. Although validation in a large cohort is warranted, the test has the potential to limit frequent cystoscopies. Patient summary: Radiotherapy is a bladder-sparing treatment in patients with bladder cancer. After treatment, these patients undergo visual inspection of the bladder by cystoscopy to detect possible recurrences. However, interpretation of cystoscopy is difficult due to the effects of radiation on the bladder lining. Hence, we analyzed the diagnostic value of a molecular urine test to detect recurrent disease in bladder cancer patients treated by radiotherapy, and we showed that the urine test has the potential to limit the number of cystoscopies.

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