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1.
J Pharm Biomed Anal ; 233: 115478, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37245329

RESUMO

In early drug discovery, hydrolytic chemical stability is routinely assessed to ensure future developability of quality compounds and stability in in vitro test environments. When conducting high-throughput hydrolytic stability analyses as part of the compound risk assessment, aggressive conditions are typically applied to allow for faster screening. However, it can be challenging to extrapolate the real stability risk and to rank compounds due to over-estimating risk based on aggressive conditions and the narrow discriminative window. In this study, critical assay parameters including temperature, concentration, and detection technique were systematically assessed using selected model compounds, and the impact and interplay of these parameters on predictive power and prediction quality were evaluated. Improved data quality was achieved using high sample concentration and reduced temperature, combined with ultraviolet (UV) detection, while mass spectrometry (MS) detection was found to be a useful complementary detection technique. Therefore, a highly discriminative stability protocol with optimized assay parameters and experimental data quality is proposed. The optimized assay can provide early guidance on the potential stability risk of a drug molecule as well as enable more confident decision-making in compound design, selection, and development.


Assuntos
Confiabilidade dos Dados , Descoberta de Drogas , Espectrometria de Massas/métodos , Estabilidade de Medicamentos
2.
Org Lett ; 25(1): 304-308, 2023 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-36583507

RESUMO

A three-component reaction of alkenyl-tethered oxime ethers, sodium metabisulfite, and aryldiazonium tetrafluoroborates under mild conditions is developed. This reaction proceeds at room temperature without any oxidants or additives, affording ß-amino sulfones with good functional group tolerance through aminosulfonylation of unactivated alkene. Mechanistic studies show that this transformation undergoes a radical process, including radical trapping with sulfur dioxide and radical 1,4-amino migration.


Assuntos
Sulfitos , Sulfonas , Éteres , Dióxido de Enxofre
3.
Pharm Dev Technol ; 26(10): 1079-1089, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34558389

RESUMO

The objective of this work is to develop extended release subcutaneous thermo-responsive in situ gel-forming delivery systems using the following commercially available triblock polymers: poly (lactic-co-glycolic acid)-poly (ethylene glycol)-poly (lactic-co-glycolic acid) (PLGA-PEG-PLGA, copolymer A & B) and poly (lactide-co-caprolactone)-poly (ethylene glycol)-poly (lactide-co-caprolactone) (PLCL-PEG-PLCL, copolymer C). Performance of two optimized formulations containing ketoprofen as a model compound, was assessed by comparing in vitro drug release profiles with in vivo performance following subcutaneous administration in rats. This work employs a Design of Experiment (DoE) approach to explore first, the relationship between copolymer composition, concentration, and gelation temperature (GT), and second, to identify the optimal copolymer composition and drug loading in the thermo-responsive formulation. Furthermore, this work discusses the disconnect observed between in vitro drug release and in vivo pharmacokinetic (PK) profiles. In vitro, both formulations showed extended-release profiles for 5-9 days, while PK parameters and plasma profiles were similar in vivo without extended release observed. In conclusion, a clear disconnection is observed between in vitro ketoprofen drug release and in vivo performance from the two thermogel formulations tested. This finding highlights a remaining challenge for thermogel formulation development, that is, being able to accurately predict in vivo behavior from in vitro results.


Assuntos
Polietilenoglicóis , Projetos de Pesquisa , Animais , Descoberta de Drogas , Liberação Controlada de Fármacos , Géis , Hidrogéis , Ratos , Temperatura
4.
Otol Neurotol ; 42(5): 726-732, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33967248

RESUMO

OBJECTIVE: This study aims to explore the feasibility of endoscopic transcanal push-trough myringoplasty (ETPM) for all types of tympanic membrane perforations (TMPs), and compare the outcomes with those of endoscopic type 1 tympanoplasty (ETT) with meatal flap elevation. STUDY DESIGN: A prospective, controlled study. METHODS: In the present study, inpatients with TMPs were divided into two groups according to the manner of tympanic membrane repair: one group received ETPM without raising the meatal flap, and the other received ETT. The operation duration, postoperative healing rate, visual analogue scale (VAS) of pain, and complication rates were compared between these two groups. RESULTS: Regardless of the size and location of the perforation, and its relationship with the malleus manubrium, myringoplasty can be completed using the ETPM method. The operation duration for different types of TMPs was shorter in the ETPM group than in the ETT group, and the difference was statistically significant (p<0.05). However, there was no statistical difference in the short-term healing rate (p>0.05) and pain VAS score (p>0.05) between these two groups. Furthermore, no intraoperative or postoperative complications occurred in both groups. CONCLUSION: ETPM without raising the meatal flap can be applied for all types of TMPs, regardless of how large the perforation is, or where it is located. This can shorten the operation duration, and has a high healing rate comparable to ETT and mild postoperative pain. Mastering some essential surgical skills under the endoscope would be helpful to ensure the success of the surgery.


Assuntos
Miringoplastia , Perfuração da Membrana Timpânica , Humanos , Estudos Prospectivos , Estudos Retrospectivos , Resultado do Tratamento , Membrana Timpânica , Perfuração da Membrana Timpânica/cirurgia , Timpanoplastia
5.
J Med Chem ; 63(24): 15564-15590, 2020 12 24.
Artigo em Inglês | MEDLINE | ID: mdl-33306391

RESUMO

A CDK9 inhibitor having short target engagement would enable a reduction of Mcl-1 activity, resulting in apoptosis in cancer cells dependent on Mcl-1 for survival. We report the optimization of a series of amidopyridines (from compound 2), focusing on properties suitable for achieving short target engagement after intravenous administration. By increasing potency and human metabolic clearance, we identified compound 24, a potent and selective CDK9 inhibitor with suitable predicted human pharmacokinetic properties to deliver transient inhibition of CDK9. Furthermore, the solubility of 24 was considered adequate to allow i.v. formulation at the anticipated effective dose. Short-term treatment with compound 24 led to a rapid dose- and time-dependent decrease of pSer2-RNAP2 and Mcl-1, resulting in cell apoptosis in multiple hematological cancer cell lines. Intermittent dosing of compound 24 demonstrated efficacy in xenograft models derived from multiple hematological tumors. Compound 24 is currently in clinical trials for the treatment of hematological malignancies.


Assuntos
Quinase 9 Dependente de Ciclina/antagonistas & inibidores , Inibidores de Proteínas Quinases/química , Piridinas/química , Animais , Apoptose/efeitos dos fármacos , Sítios de Ligação , Linhagem Celular Tumoral , Quinase 9 Dependente de Ciclina/metabolismo , Cães , Avaliação Pré-Clínica de Medicamentos , Meia-Vida , Neoplasias Hematológicas/tratamento farmacológico , Neoplasias Hematológicas/patologia , Humanos , Camundongos , Simulação de Acoplamento Molecular , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Inibidores de Proteínas Quinases/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Piridinas/metabolismo , Piridinas/farmacologia , Piridinas/uso terapêutico , Ratos , Solubilidade , Relação Estrutura-Atividade , Ensaios Antitumorais Modelo de Xenoenxerto
6.
J Int Med Res ; 48(8): 300060520944303, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32865080

RESUMO

Branchial fistulas are uncommon in the clinical setting. The coexistence of first and second branchial fistulas has not been previously reported. We herein describe a 12-year-old girl who presented with a 2-year history of repeated swelling and purulence behind the right earlobe and neck. According to the patient's physical and auxiliary examination findings, she was diagnosed with coexisting first and second branchial fistulas, both of which were completely removed by surgery. No clinical signs of fistula recurrence were present at the patient's 20-month postoperative follow-up. Ipsilateral coexisting first and second branchial fistulas are very rare; thus, a false-positive diagnosis can easily occur if the doctor does not carefully perform specialized physical examinations. Surgery is an effective method for treating this condition. Adequate preoperative imaging preparation is imperative to ensure the most effective course of treatment. The purpose of this article is to improve clinicians' awareness of this disease, thereby effectively reducing the rates of missed diagnosis and recurrence.


Assuntos
Anormalidades Craniofaciais , Fístula , Doenças Faríngeas , Região Branquial/diagnóstico por imagem , Região Branquial/cirurgia , Criança , Feminino , Fístula/diagnóstico por imagem , Fístula/cirurgia , Humanos , Pescoço
7.
J Int Med Res ; 48(8): 300060520946517, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32851892

RESUMO

Extrapulmonary small cell carcinoma (EPSCC) affecting the external auditory canal (EAC) is uncommon. We herein report a case involving a 56-year-old man with EPSCC of the EAC who had a 48-year history of recurrent purulent discharge in both ears and a 20-day history of right ear pain and hemorrhage followed by incomplete right eyelid closure and an askew mouth. He underwent surgical removal of middle ear granulation tissue, residual ossicles, and a right EAC mass. Postoperatively, pathomorphological examination combined with immunohistochemical staining supported a diagnosis of small cell carcinoma. Radiation therapy at a dose of 60.06 Gy in 33 daily fractions was completed 1 month after surgery, and synchronous etoposide-cisplatin regimen chemotherapy was performed for two cycles and four sequential cycles. One year postoperatively, magnetic resonance imaging showed no tumor in the ear; however, computed tomography showed multiple liver space-occupying lesions that were considered to indicate liver metastasis. Further chemotherapy was performed, but the patient died 15 months postoperatively. This case indicates that timely and accurate chemoradiotherapy is likely the most reasonable approach to EPSCC of the EAC given the aggressiveness of this tumor.


Assuntos
Carcinoma de Células Pequenas , Neoplasias da Orelha , Carcinoma de Células Pequenas/diagnóstico por imagem , Carcinoma de Células Pequenas/tratamento farmacológico , Meato Acústico Externo/diagnóstico por imagem , Meato Acústico Externo/cirurgia , Neoplasias da Orelha/diagnóstico por imagem , Neoplasias da Orelha/cirurgia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
8.
Water Sci Technol ; 79(10): 1995-2004, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31294716

RESUMO

Given the adverse health effects of antimony (Sb), there is an increased focus on developing methods to remove this toxic metal from contaminated water bodies. To effectively remove Sb(V), a new nanostructured Fe-Cu-Al trimetal oxide was fabricated using co-precipitation method at ambient temperature. The Fe-Cu-Al trimetal oxide was very effective at removing Sb(V) from water; it had a maximal adsorption capacity of 169.1 mg/g at pH 7.0, a capacity that was competitive with most other reported adsorbents. The obtained amorphous oxide had a high pH point of zero charge (pHpzc = 8.8) and good adsorption Sb(V) efficiency over a wide pH range (4.0-8.0). Sb(V) uptake was achieved mainly through an ion-exchange reaction between Sb(V) ions and hydroxyl groups on the surface of the oxide. Given its good removal performance, high selectivity, and simple synthesis, this novel Fe-Cu-Al trimetal oxide offers a promising alternate for removing antimony contamination from aquatic environments.


Assuntos
Antimônio , Nanoestruturas , Adsorção , Óxidos
9.
Sci Rep ; 7(1): 1558, 2017 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-28484259

RESUMO

Few studies have been published on the mechanisms of hypoxia response and tolerance in jellyfish, especially with respect to the regulatory mechanism at the molecular level. In this study, Aurelia sp.1, which is frequently found in Chinese coastal waters, was cultivated in a hypoxic system to determine the molecular mechanisms underlying its hypoxic response by studying the physiological activity, gene expression and metabolite contents in the prolyl hydroxylase domain (PHD)-hypoxia inducible factor (HIF) oxygen-sensing system. Physiological activity; the expression of PHD, HIF, ALDO (fructose-bisphosphate aldolase), PDK (pyruvate dehydrogenase kinase), and LDH (lactate dehydrogenase) genes; and the lactic acid content in medusae were significantly affected by hypoxia. The up-regulation of ALDO, PDK and LDH, which was directly or indirectly induced by HIF, mediated the transition from aerobic respiration to anaerobic glycolysis in the medusae. In polyps, there was a slight increase in the expression of HIF, PHD and ALDO, no obvious change in that of PDK and a slight decrease in that of LDH throughout the experiment; however, these changes were insufficient to induce the shift. This study provides a scientific basis for elucidating the regulatory mechanism underlying the PHD-HIF oxygen-sensing system in Aurelia sp.1.


Assuntos
Hipóxia/genética , Cifozoários/genética , Cifozoários/fisiologia , Animais , Regulação da Expressão Gênica , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , L-Lactato Desidrogenase/metabolismo , Ácido Láctico/metabolismo , Estágios do Ciclo de Vida , Oxigênio/metabolismo , Cifozoários/crescimento & desenvolvimento
10.
Artigo em Chinês | MEDLINE | ID: mdl-27197465

RESUMO

We report a rare case of pleomorphic adenoma arising from the nasal septum. A 37-year-old woman presented with a 1-year-history of right-sided occasional epistaxis. Computed tomographic scans revealed an oval mass in the right nasal cavity. The tumor was removed endoscopically with endonasal approach. The microscopic finding showed numbers of myoepithelial cells and duct-like structures consisting of loose myxoid stroma. This lesion had histological characteristics of a pleomorphic adenoma, and this was confirmed by immunohistochemical expression of cytokeratin, S-100 protein and SMA. Her post-operative course was uneventful, and she is currently free from the disease 1.5 years after surgery.


Assuntos
Adenoma Pleomorfo/diagnóstico , Septo Nasal/patologia , Neoplasias Nasais/diagnóstico , Actinas/metabolismo , Adenoma Pleomorfo/cirurgia , Adulto , Endoscopia , Epistaxe , Células Epiteliais , Feminino , Humanos , Queratinas/metabolismo , Neoplasias Nasais/cirurgia , Proteínas S100/metabolismo
11.
Pharmacol Res Perspect ; 3(5): e00175, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26516587

RESUMO

Off-target pharmacology may contribute to both adverse and beneficial effects of a new drug. In vitro pharmacological profiling is often applied early in drug discovery; there are fewer reports addressing the relevance of broad profiles to clinical adverse effects. Here, we have characterized the pharmacological profile of the active metabolite of fostamatinib, R406, linking an understanding of drug selectivity to the increase in blood pressure observed in clinical studies. R406 was profiled in a broad range of in vitro assays to generate a comprehensive pharmacological profile and key targets were further investigated using functional and cellular assay systems. A combination of traditional literature searches and text-mining approaches established potential mechanistic links between the profile of R406 and clinical side effects. R406 was selective outside the kinase domain, with only antagonist activity at the adenosine A3 receptor in the range relevant to clinical effects. R406 was less selective in the kinase domain, having activity at many protein kinases at therapeutically relevant concentrations when tested in multiple in vitro systems. Systematic literature analyses identified KDR as the probable target underlying the blood pressure increase observed in patients. While the in vitro pharmacological profile of R406 suggests a lack of selectivity among kinases, a combination of classical searching and text-mining approaches rationalized the complex profile establishing linkage between off-target pharmacology and clinically observed effects. These results demonstrate the utility of in vitro pharmacological profiling for a compound in late-stage clinical development.

12.
PLoS One ; 9(6): e100057, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24926666

RESUMO

The maintenance of physiological oxygen homeostasis is mediated by hypoxia-inducible factor (HIF), a key transcriptional factor of the PHD-HIF system in all metazoans. However, the molecular evolutionary origin of this central physiological regulatory system is not well characterized. As the earliest eumetazoans, Cnidarians can be served as an interesting model for exploring the HIF system from an evolutionary perspective. We identified the complete cDNA sequence of HIF-1α (ASHIF) from the Aurelia sp.1, and the predicted HIF-1α protein (pASHIF) was comprised of 674 amino acids originating from 2,025 bp nucleotides. A Pairwise comparison revealed that pASHIF not only possessed conserved basic helix-loop-helix (bHLH) and Per-Arnt-Sim (PAS) domains but also contained the oxygen dependent degradation (ODD) and the C-terminal transactivation domains (C-TAD), the key domains for hypoxia regulation. As indicated by sequence analysis, the ASHIF gene contains 8 exons interrupted by 7 introns. Western blot analysis indicated that pASHIF that existed in the polyps and medusa of Aurelia. sp.1 was more stable for a hypoxic response than normoxia.


Assuntos
Evolução Molecular , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Cifozoários/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , Expressão Gênica , Humanos , Dados de Sequência Molecular , Filogenia , Homologia de Sequência
13.
Ying Yong Sheng Tai Xue Bao ; 24(3): 847-52, 2013 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-23755504

RESUMO

Taking the moon jellyfish Aurelia sp. commonly found in our coastal sea areas as test object, its genome DNA was extracted, the partial sequences of mt-16S rDNA (650 bp) and mt-COI (709 bp) were PCR-amplified, and, after purification, cloning, and sequencing, the sequences obtained were BLASTn-analyzed. The sequences of greater difference with those of the other jellyfish were chosen, and eight specific primers for the mt-16S rDNA and mt-COI of Aurelia sp. were designed, respectively. The specificity test indicated that the primer AS3 for the mt-16S rDNA and the primer AC3 for the mt-COI were excellent in rapidly detecting the target jellyfish from Rhopilema esculentum, Nemopilema nomurai, Cyanea nozakii, Acromitus sp., and Aurelia sp., and thus, the techniques for the molecular identification and detection of moon jellyfish were preliminarily established, which could get rid of the limitations in classical morphological identification of Aurelia sp. , being able to find the Aurelia sp. in the samples more quickly and accurately.


Assuntos
DNA Ribossômico/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Mitocôndrias/genética , Proteínas Mitocondriais/genética , Cifozoários/genética , Animais , RNA Ribossômico 16S/genética
14.
Ying Yong Sheng Tai Xue Bao ; 23(11): 3207-17, 2012 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-23431810

RESUMO

Aurelia spp. is a cosmopolitan coastal species, and also, one dominant species of large jellyfish in the coastal waters of China. In recent years, Aurelia spp. bloom events occur frequently in the world, causing severe damage to marine ecosystems, coastal economy, and society development. Aurelia spp. has a complicated life history comprising a benthic asexually-reproducing polyp generation and a sexually-reproducing medusa generation, and various vegetative reproduction (budding, strobilation, and podocyst production) and sexual reproduction. Surrounding physical and biological factors affect each growth stage of Aurelia spp., especially the juvenile stage of planktonic-benthic life cycle, which has major effect on the population dynamics of Aurelia spp. This paper reviewed the research advances in the effects of environmental factors on Aurelia spp. at its different growth and development stages, and discussed some problems worthy of further study, aimed to provide useful reference for the research of the key factors controlling the jellyfish blooms in coastal waters of China.


Assuntos
Ecossistema , Meio Ambiente , Oceanos e Mares , Cifozoários/crescimento & desenvolvimento , Animais , Estágios do Ciclo de Vida/fisiologia , Reprodução/fisiologia , Cifozoários/fisiologia
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