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1.
Front Pediatr ; 11: 1259744, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38089687

RESUMO

Objectives: The aim of this article was to compare the differences between Intergrowth-21st (IG-21) and Fenton growth standards in the classification of intrauterine and extrauterine growth restriction (EUGR) in eastern Chinese preterm infants, and detect which one can better relate to neonatal diseases and predict the physical growth outcomes at 3-5 years old. Methods: Premature infants admitted to a tertiary pediatric hospital in Shanghai, China, from 2016 to 2018 were enrolled. Prenatal information, neonatal diseases during hospitalization, and anthropometric data (weight, height, and head circumference) at birth and at discharge were collected and analyzed. Physical growth outcomes (short stature, thinness, and overweight) were examined by telephone investigations in 2021 at age 3-5 years. Results: The medium gestational age and birth weight of the included 1,065 preterm newborns were 33.6 weeks and 1,900 g, respectively. The IG-21 curves diagnosed more newborns with small for gestational age (SGA) (19% vs. 14.7%) and fewer newborns with longitudinal EUGR on height (25.5% vs. 27.9%) and head circumference (17.9% vs. 24.7%) compared to Fenton curves. Concordances between Fenton and IG-21 standards were substantial or almost perfect in the classification of SGA and longitudinal EUGR, but minor in cross-sectional EUGR. EUGR identified by Fenton curves was better related to neonatal diseases than IG-21 curves. There were no statistical significances in the prediction of short stature, thinness, and overweight at 3-5 years old between the two charts. Conclusions: IG-21 growth standards are not superior to Fenton in assessing preterm growth and development in the eastern Chinese population.

2.
J Pharm Biomed Anal ; 215: 114752, 2022 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-35483232

RESUMO

Control of process impurities during manufacturing of drug substance is critical to ensure quality and process robustness. During commercial process development for the gefapixant citrate drug substance, several process impurities were found to derive from sulfuryl chloride, an impurity in the raw material, chlorosulfonic acid (CSA). This made controlling the CSA quality essential for commercial production of this drug substance. Various direct analysis methods were evaluated and found unsuitable because of the highly reactive nature and structural similarity of sulfuryl chloride and CSA. Therefore, a robust derivatization reversed-phase high performance liquid chromatography (RP-HPLC) method was developed and validated to accurately quantify sulfuryl chloride in CSA. The derivatization method was utilized to evaluate many CSA batches from different commercial suppliers and to establish a correlation between sulfuryl chloride levels in CSA and the levels of process impurities in downstream materials. The methodology described herein informed the development of setting the specification on sulfuryl chloride for CSA to ensure a robust process for manufacturing high-quality gefapixant citrate drug substance. The derivatization method was successfully validated and transferred to the commercial commodity supplier for release testing of CSA as a raw material for gefapixant citrate commercial campaigns.


Assuntos
Cloretos , Contaminação de Medicamentos , Cromatografia Líquida de Alta Pressão/métodos , Citratos , Contaminação de Medicamentos/prevenção & controle , Pirimidinas , Reprodutibilidade dos Testes , Sulfonamidas , Ácidos Sulfônicos
3.
Eng Life Sci ; 20(11): 441-450, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33204231

RESUMO

Biocatalytic membrane takes advantages of reaction-separation integration as well as enzyme immobilization, which has attracted increasing attentions in online detection and biomanufacturing. However, the high preparation cost, inferior comprehensive performance, and low stability limit its applications. Thus, besides enzyme immobilization, more efforts should be made in biocatalytic membrane configuration design for a specific application to enhance the synergistic effect of reaction and separation and improve its operating stability. This review summarized the recent progress on biocatalytic membrane preparation, discussed different membrane configurations for various applications, finally proposed several challenges and possible solutions, which provided directions and guides for the development and industrialization of biocatalytic membrane.

4.
Appl Microbiol Biotechnol ; 102(10): 4345-4354, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29602982

RESUMO

Ficellomycin is an aziridine antibiotic produced by Streptomyces ficellus, which displays high in vitro activity against Gram-positive bacteria including multidrug resistant strains of Staphylococcus aureus. Compared to currently available antibiotics, ficellomycin exhibits a unique mechanism of action-it impairs the semiconservative DNA replication by inducing the formation of deficient 34S DNA fragments, which lack the ability to integrate into larger DNA pieces and eventually the complete bacterial chromosome. Until recently, some important progress has been made in research on ficellomycin synthesis and biosynthesis, opening the perspective to develop a new generation of antibiotics with better clinical performance than the currently used ones. In this review, we will cover the discovery and biological activity of ficellomycin, its biosynthesis, mode of action, and related synthetic analogs. The role of ficellomycin and its analogs as an important source of drug prototypes will be discussed together with future research prospects.


Assuntos
Antibacterianos/biossíntese , Antibacterianos/farmacologia , Peptídeos/química , Antibacterianos/química , Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Descoberta de Drogas , Farmacorresistência Bacteriana/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intercelular , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Peptídeos/farmacologia , Peptídeos/uso terapêutico
5.
Carcinogenesis ; 25(2): 283-7, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14604898

RESUMO

Bidi cigarettes, or bidis, are a tobacco product that originated in India and have been gaining popularity in the USA during the past few years, particularly with adolescents. As with conventional cigarettes, tobacco and smoke from bidis contain chemical constituents including carcinogenic chemicals such as the tobacco-specific nitrosamines (TSNAs). To help better assess the potential public health risk associated with bidi cigarettes, we developed modern high throughput methods to accurately quantify TSNA levels in tobacco and mainstream cigarette smoke particulate. We determined the TSNA levels in the tobacco filler and mainstream smoke from 14 bidi cigarette brands. In the bidi tobacco filler, the 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) levels ranged from 0.09 to 0.85 microg/g, while N'-nitrosonornicotine (NNN) levels ranged from 0.15 to 1.44 microg/g. These amounts are comparable with those in typical American blended cigarettes. The levels of NNK in mainstream smoke from bidis ranged from 2.13 to 25.9 ng/cigarette, and NNN levels ranged from 8.56 to 62.3 ng/cigarette. The wide variation in the TSNA levels most probably reflects the hand-rolled nature of the bidi cigarettes, resulting in a product with less homogenous tobacco amount and a wider variation in overall cigarette construction quality. TSNA levels of bidis were comparable with those of conventional cigarettes, and bidis should not be considered a lower-risk alternative tobacco product. Our analytical findings concur with the previous biologic and biochemical evidence supporting epidemiologic studies linking bidi use with various cancers, especially oral cavity and lung cancers.


Assuntos
Nicotiana/química , Nitrosaminas/análise , Fumaça/análise , Alcatrões/análise
6.
Nicotine Tob Res ; 5(3): 323-31, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12791527

RESUMO

Tobacco-specific nitrosamines (TSNAs) are one of the major classes of carcinogens found in tobacco products. As part of collaborative efforts to reduce tobacco use and resulting disease, the U.S. Centers for Disease Control and Prevention (CDC) carried out a two-phase investigation into the worldwide variation of the levels of TSNAs in cigarette tobacco. In the first phase, representatives of the World Health Organization (WHO) purchased cigarettes; scientists from the CDC subsequently measured the levels of TSNAs in tobacco from 21 different countries. Although the data collected from this initial survey suggested that globally marketed U.S.-brand cigarettes typically had higher TSNA levels than locally popular non-U.S. cigarettes in many countries, the number of samples limited the statistical power of the study. To improve statistical power and to ensure adequate sampling, the CDC conducted a second survey of 14 countries. In addition to the United States, the CDC selected the world's 10 most populous countries and three additional countries, so that at least two countries from each of the six WHO regions were represented. For each country, the CDC compared 15 packs of Marlboro cigarettes, which is the world's most popular brand of cigarettes, with 15 packs of a locally popular non-U.S. brand in the study country. Marlboro cigarettes purchased in 11/13 foreign countries had significantly higher tobacco TSNA levels than the locally popular non-U.S. brands purchased in the same country. The findings suggest that TSNA levels in tobacco can be substantially reduced in some cigarettes.


Assuntos
Carcinógenos/análise , Nicotiana/química , Nitrosaminas/análise , Fumar , Coleta de Dados , Humanos , Estados Unidos
7.
Anal Bioanal Chem ; 373(7): 647-55, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12185578

RESUMO

A plasma desorption mass spectrometry study was made on the properties of glucose and glucose/glucuronic acid thin films as matrices for amino acids, small and large peptides and insulin. Amino acids and small peptides are distributed throughout the film as it is formed from aqueous solutions and the mass spectra are similar to what is observed for nitrocellulose matrices. AngiotensinII (angII), insulin, and reduced insulin containing the separated A- and B-chains concentrate at the surface of the film due to the hydrophobic interaction. Extensive positive and negative fragmentation patterns are observed for angII using the glucose glass film. The fragment ions appear to be formed from layers just below the surface of the film. The co-matrix of glucuronic acid/glucose produces a higher molecular ion yield. The spectrum of insulin in glucuronic acid/glucose consists mainly of positive ions with a fragmentation pattern from the B-chain. The spectrum of reduced insulin using a nitrocellulose matrix gives B-chain ions but glucose/glucuronic acid gives A-chain ions in both the positive and negative ion spectra. The fragmentation patterns of the A-chain and B-chain ions are sensitive to the nature of the matrix. An extensive negative ion A-chain fragmentation pattern was observed with glutamate ions serving as the charge centers. The reasons for the behavior of the A- and B-chain fragmentation patterns in these matrices is not clear.


Assuntos
Angiotensina II/análise , Glucose/química , Insulina/análise , Espectrometria de Massas/métodos , Sequência de Aminoácidos , Aminoácidos/análise , Animais , Bovinos , Vidro , Ácido Glucurônico/química , Insulina/sangue , Insulina/química , Íons , Dados de Sequência Molecular , Peptídeos/análise , Análise de Sequência de Proteína
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