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1.
Toxins (Basel) ; 13(12)2021 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-34941722

RESUMO

Venoms of solitary wasps are utilized for prey capture (insects and spiders), paralyzing them with a stinger injection to be offered as food for their larvae. Thus, the identification and characterization of the components of solitary wasp venoms can have biotechnological application. In the present study, the venom components profile of a solitary scoliid wasp, Campsomeriella annulata annulata, was investigated through a comprehensive analysis using LC-MS and -MS/MS. Online mass fingerprinting revealed that the venom extract contains 138 components, and MS/MS analysis identified 44 complete sequences of the peptide components. The peptides are broadly divided into two classes: bradykinin-related peptides, and linear α-helical peptides. Among the components of the first class, the two main peptides, α-campsomerin (PRLRRLTGLSPLR) and ß-campsomerin (PRLRRLTGLSPLRAP), had their biological activities evaluated. Both peptides had no effects on metallopeptidases [human neprilysin (NEP) and angiotensin-converting enzyme (ACE)] and acetylcholinesterase (AChE), and had no cytotoxic effects. Studies with PC12 neuronal cells showed that only α-campsomerin was able to enhance cell viability, while ß-campsomerin had no effect. It is noteworthy that the only difference between the primary structures from these peptides is the presence of the AP extension at the C-terminus of ß-campsomerin, compared to α-campsomerin. Among the linear α-helical peptides, annulatin (ISEALKSIIVG-NH2) was evaluated for its biological activities. Annulatin showed histamine releasing activity from mast cells and low hemolytic activity, but no antimicrobial activities against all microbes tested were observed. Thus, in addition to providing unprecedented information on the whole components, the three peptides selected for the study suggest that molecules present in solitary scoliid wasp venoms may have interesting biological activities.


Assuntos
Proteínas de Insetos/química , Proteínas de Insetos/toxicidade , Células PC12/efeitos dos fármacos , Fenômenos Toxicológicos/efeitos dos fármacos , Venenos de Vespas/química , Venenos de Vespas/toxicidade , Animais , Japão , Ratos
2.
PLoS One ; 15(8): e0237254, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32853204

RESUMO

Although many novel phase I designs have been developed in recent years, few studies have discussed how to incorporate external information into dose-finding designs. In this paper, we first propose a new method for developing a phase I design, Bayesian optimal interval design (BOIN)[Liu S et al. (2015), Yuan Y et al. (2016)], for formally incorporating historical information. An algorithm to automatically generate parameters for prior set-up is introduced. Second, we propose a method to relax the fixed boundaries of the BOIN design to be adaptive, such that the accumulative information can be used more appropriately. This modified design is called adaptive BOIN (aBOIN). Simulation studies to examine performances of the aBOIN design in small and large sample sizes revealed comparable performances for the aBOIN and original BOIN designs for small sample sizes. However, aBOIN outperformed BOIN in moderate sample sizes. Simulation results also showed that when historical trials are conducted in settings similar to those for the current trial, their performance can be significantly improved. This approach can be applied directly to pediatric cancer trials, since all phase I trials in children are followed by similar efficient adult trials in the current drug development paradigm. However, when information is weak, operating characteristics are compromised.


Assuntos
Ensaios Clínicos Fase I como Assunto , Desenvolvimento de Medicamentos , Adulto , Algoritmos , Antineoplásicos/uso terapêutico , Teorema de Bayes , Criança , Ensaios Clínicos Fase I como Assunto/métodos , Simulação por Computador , Desenvolvimento de Medicamentos/métodos , Humanos , Neoplasias/tratamento farmacológico , Projetos de Pesquisa , Tamanho da Amostra , Fenômenos Toxicológicos/efeitos dos fármacos
3.
Eur J Med Chem ; 123: 90-104, 2016 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-27474926

RESUMO

A novel series (13) of isoxazoline functionalized coumarins was synthesized through 1,3-dipolar cyclization of nitrile oxides with Allylated coumarins. Synthesis of effective and target selective immunostimulators through conjugation of diversely substituted isoxazolines and 7-hydroxycoumarins is the focus of the present article. The proposed synthetic scheme was observed to be highly regiospecific yielding attempted conjugates in good yield (>90%). Kinetic resolution of the racemates was carried out by employing lipase B from Candida antarctica (CALB). The synthesized compounds were screened in vitro and in vivo for their biological activities viz. toxicity and impact on splenocyte proliferation (T- and B-cell proliferation), antibody production (HA titre), delayed-type hypersensitivity reaction (DTH), T-cell subtypes (CD4 and CD8), cytokine production (IL-2, IFN-γ, and IL-4) and NO (macrophage) production. Our results establish that isoxazoline functionalized coumarins exhibit excellent immune potentiating activity especially compounds 2, 4 and 8 whose activity is more than that of Levimasole as standard. The structure activity relations are explained in light of the structural/functional aspects of tested compounds. To the best of our knowledge the presented work is first of its kind and is presaged to prove very useful for the design and synthesis of bis-heterocycle based novel, therapeutically selective and effective immunopotentiators.


Assuntos
Adjuvantes Imunológicos/síntese química , Cumarínicos/farmacologia , Adjuvantes Imunológicos/farmacologia , Animais , Anticorpos/efeitos dos fármacos , Células Cultivadas , Cumarínicos/síntese química , Cumarínicos/química , Citocinas/efeitos dos fármacos , Humanos , Hipersensibilidade Tardia/tratamento farmacológico , Sistema Imunitário/efeitos dos fármacos , Isoxazóis/química , Linfócitos/efeitos dos fármacos , Relação Estrutura-Atividade , Fenômenos Toxicológicos/efeitos dos fármacos
4.
J Inorg Biochem ; 151: 10-7, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26226450

RESUMO

In recent years larval stage zebrafish have been emerging as a standard vertebrate model in a number of fields, ranging from developmental biology to pharmacology and toxicology. The tyrosinase inhibitor 1-phenyl-2-thiourea (PTU) is used very widely with larval zebrafish to generate essentially transparent organisms through inhibition of melanogenesis, which has enabled many elegant studies in areas ranging from neurological development to cancer research. Here we show that PTU can have dramatic synergistic and antagonistic effects on the chemical toxicology of different mercury compounds. Our results indicate that extreme caution should be used when employing PTU in toxicological studies, particularly when studying toxic metal ions.


Assuntos
Compostos de Mercúrio/toxicidade , Feniltioureia/farmacologia , Fenômenos Toxicológicos/efeitos dos fármacos , Animais , Complexos de Coordenação/química , Ativação Enzimática/efeitos dos fármacos , Compostos de Mercúrio/química , Feniltioureia/química , Teoria Quântica , Peixe-Zebra
5.
J Anim Sci ; 93(4): 1942-51, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26020217

RESUMO

Our objectives were to determine an effective, yet safe, daily dose of sodium chlorate for reducing fecal shedding of generic Escherichia coli in mature ewes. In a completely randomized experimental design, 25 Targhee ewes (age ∼ 18 mo; BW = 62.5 ± 7.3 kg, mean ± SD) were assigned randomly to 1 of 5 sodium chlorate treatments, which were administered in the drinking water for 5 consecutive days. Treatments were control group (no sodium chlorate) and 4 targeted levels of daily sodium chlorate intake: 30, 60, 90, and 120 mg · kg(-1) BW · d(-1) for 5 d. Individual ewe ad libitum intake of water (with treatments) was measured daily, and BW was measured at the beginning of and 15 and 51 d after the 5-d treatment period. Serum chlorate, whole blood methemoglobin and packed-cell volume (PCV), and fecal generic E. coli and general Enterobacteriaceae coliforms were measured from corresponding samples collected at the end of the 5-d treatment period. Average daily intakes of sodium chlorate from drinking water treatments were 95%, 91%, 90%, and 83% of the target treatment intakes of 30, 60, 90, and 120 mg · kg(-1) BW · d(-1), respectively. Daily sodium chlorate intake remained constant for all treatment groups except for ewes offered 120 mg NaClO3 · kg(-1) BW · d(-1), which decreased (quadratic; P = 0.04) over the course of the 5-d treatment period. This decrease in sodium chlorate intake indicated that the 120-mg NaClO3 level may have induced either toxicity and/or an aversion to the drinking water treatment. Serum chlorate concentrations increased (quadratic; P < 0.001) with increasing sodium chlorate intake. At the end of the 5-d treatment period, mean (least squares ± SEM) serum chlorate concentrations for ewes offered 30, 60, 90, and 120 mg NaClO3 · kg(-1) BW · d(-1) were 15.6 ± 14.1, 32.8 ± 15.8, 52.9 ± 14.1, and 90.3 ± 14.1 µg/mL, respectively. Whole blood methemoglobin and PCV were similar (P = 0.31 to 0.81) among the control group and ewes offered sodium chlorate. Likewise, BW was not affected by sodium chlorate (P > 0.27). Ewes consuming approximately 55 mg NaClO3 · kg(-1) BW · d(-1) or more (i.e., ewes offered 60, 90, and 120 mg) had a >1.4 log unit reduction in fecal E. coli and Enterobacteriaceae coliforms compared with control ewes. We suggest that for a short-term, 5-d dosing strategy, 55 to 81 mg NaClO3 · kg(-1) BW · d(-1) is an effective, yet safe, daily oral dose range for mature ewes to achieve a 97% to 99% reduction in fecal shedding of generic E. coli.


Assuntos
Cloratos/toxicidade , Infecções por Escherichia coli/veterinária , Escherichia coli/efeitos dos fármacos , Fezes/microbiologia , Doenças dos Ovinos/tratamento farmacológico , Carneiro Doméstico/microbiologia , Administração Oral , Criação de Animais Domésticos/métodos , Animais , Peso Corporal/efeitos dos fármacos , Cloratos/administração & dosagem , Cloratos/sangue , Cloratos/farmacologia , Cloratos/uso terapêutico , Relação Dose-Resposta a Droga , Infecções por Escherichia coli/tratamento farmacológico , Feminino , Herbicidas/administração & dosagem , Herbicidas/farmacologia , Herbicidas/uso terapêutico , Metemoglobina/metabolismo , Ovinos , Doenças dos Ovinos/microbiologia , Carneiro Doméstico/fisiologia , Fenômenos Toxicológicos/efeitos dos fármacos , Resultado do Tratamento
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