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1.
Molecules ; 27(5)2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35268559

RESUMO

Endophytes, being the co-evolution partners of green host plants, are factories of pharmaceutically valuable novel natural products. Cochliobolus sp. APS1, an endophyte of Andrographis paniculata (Green Chiretta), produces a plethora of natural bioactive compounds and the multipotent alkaloid Aziridine, 1-(2-aminoethyl)-, is the prime one among them. The isolate exhibited antibacterial, anti-biofilm, and antilarval potency. The MIC and MBC values of the ethyl-acetate culture extract ranged from 15.62 to 250 µg/mL against ten pathogenic microorganisms (including MRSA and VRSA). Killing kinetics data along with the leakage of macromolecules into the extracellular environment supports the cidal activity of the antibacterial principles. The broad spectrum antibacterial activity of Aziridine, 1-(2-aminoethyl)-, was optimized by a one-variable-at-a-time system coupled with response surface methodology, which led to a 45% enhancement of the antibacterial activity. The maximum response (22.81 ± 0.16 mm of zone of inhibition against MRSA) was marked in 250 mL Erlenmeyer flask containing 90 mL potato dextrose broth supplemented with (g%/L) glucose, 9.7; urea concentration, 0.74; with medium pH 6.48; after 8.76 days of incubation at 26 °C. APS1 strongly inhibited biofilm formation in the tested pathogenic microorganisms and acts as a larvicidal agent against the Dengue-vector Aedes aegypti. This is probably the first report of Aziridine, 1-(2-aminoethyl)-, from any endophytic source. Cochliobolus sp. APS1 possesses industrial importance for the production of bioactive alkaloids.


Assuntos
Andrographis paniculata
2.
Arch Dis Child Educ Pract Ed ; 106(6): 367-369, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33246923

RESUMO

A family liaison team was developed to improve communication between intensive care unit patients and their families during the COVID-19 pandemic.


Assuntos
COVID-19 , Pandemias , Comunicação , Família , Humanos , Unidades de Terapia Intensiva , Pandemias/prevenção & controle , SARS-CoV-2
3.
Chembiochem ; 19(20): 2173-2177, 2018 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-30079487

RESUMO

Biochemical assays that can identify ß-lactamase activity directly from patient samples have the potential to significantly improve the treatment of bacterial infections. However, current ß-lactamase probes do not have the sensitivity needed to measure ß-lactam resistance directly from patient samples. Here, we report the development of an instrument-free signal amplification technology, DETECT, that connects the activity of two enzymes in series to effectively amplify the activity of ß-lactamase 40 000-fold, compared to the standard ß-lactamase probe nitrocefin.


Assuntos
Infecções Bacterianas/diagnóstico , Infecções Bacterianas/microbiologia , beta-Lactamases/urina , Cefalosporinas/química , Humanos , Limite de Detecção , Resistência beta-Lactâmica
4.
Org Biomol Chem ; 8(5): 1052-7, 2010 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-20165795

RESUMO

The objective of this study was to evaluate the possibility of photoinduced stack/rod electron transfer in surface "zipper" architectures composed of stacks of blue (B) naphthalenediimides (NDIs) along strings of oligophenylethynyl (OPE) rods. The synthesis and characterization of anionic and cationic multichromophoric OPE-B systems are reported. Absorption spectra suggest that in OPE-B systems, planarity and thus absorption and conductivity of the OPE can possibly be modulated by intramolecular stacking of the surrounding NDIs, although interfering contributions from aggregation remain to be differentiated. Among surface architectures constructed with OPE-B and POP-B systems by zipper and layer-by-layer (LBL) assembly, photocurrents generated by OPE-B zippers exhibit the best critical thickness and fill factors. These findings confirm the existence and functional relevance of topologically matching zipper architectures. In OPE-B zippers, OPEs generate much more photocurrent than the blue NDIs. Ultrafast electron transfer from OPEs to NDIs accounts for these photocurrents, providing wavelength-controlled access to rod-stack charge separation, and thus to formal supramolecular n/p-heterojunctions (SHJs). NDI excitation is not followed by the complementary hole transfer to the OPE rod. Scaffolds with higher HOMOs will be needed to integrate blue NDIs into SHJ photosystems.


Assuntos
Alcinos/química , Naftalimidas/química , Éteres Fenílicos/química , Alcinos/síntese química , Transporte de Elétrons , Conformação Molecular , Estrutura Molecular , Naftalimidas/síntese química , Éteres Fenílicos/síntese química , Fotoquímica , Espectrofotometria
5.
Chem Commun (Camb) ; 56(24): 3516-3519, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32101196

RESUMO

The expression of beta-lactamases in bacteria is a central cause of drug resistance. In this report, we present a beta-lactamase chemiluminescent probe, termed CCP, which can for the first time detect beta-lactamase activity via chemiluminescence and can detect beta lactamase with a sensitivity that is 4-orders of magnitude higher than the commercially available fluorescent lactamase substrate fluorocillin.


Assuntos
Antibacterianos , Cefalosporinas , Farmacorresistência Bacteriana , Escherichia coli/enzimologia , Corantes Fluorescentes , beta-Lactamases/análise , Luminescência
6.
J Phys Chem A ; 113(29): 8202-12, 2009 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-19569678

RESUMO

The photophysical properties of two hybrid multichromophoric systems consisting of an oligophenylethynyl (OPE) scaffold decorated by 10 red or blue naphthalene diimides (NDIs) have been investigated using femtosecond spectroscopy. Ultrafast charge separation was observed with both red and blue systems. However, the nature of the charge-separated state and its lifetime were found to differ substantially. For the red system, electron transfer occurs from the OPE scaffold to an NDI unit, independently of whether the OPE or an NDI is initially excited. However, charge separation upon OPE excitation is about 10 times faster, and takes place with a 100 fs time constant. The average lifetime of the ensuing charge-separated state amounts to about 650 ps. Charge separation in the blue system depends on which of the OPE scaffold or an NDI is excited. In the first case, an electron is transferred from the OPE to an NDI and the hole subsequently shifts to another NDI unit, whereas in the second case symmetry-breaking charge separation between two NDI units occurs. Although the charges are located on two NDIs in both cases, different recombination dynamics are observed. This is explained by the location of the ionic NDI moieties that depends on the charge separation pathway, hence on the excitation wavelength. The very different dynamics observed with red and blue systems can be accounted for by the oxidation potentials of the respective NDIs that are higher and lower than that of the OPE scaffold. Because of this, the relative energies of the two charge-separated states (hole on the OPE or an NDI) are inverted.


Assuntos
Alcinos/química , Éteres/química , Imidas/química , Naftalenos/química , Absorção , Cor , Transporte de Elétrons , Espectrometria de Fluorescência , Fatores de Tempo
7.
J Pediatr Gastroenterol Nutr ; 46(1): 117-20, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18162847

RESUMO

The IMPACT questionnaire was developed in Canada to measure quality of life in children with inflammatory bowel disease (IBD). In the present study, 20 children with IBD completed 2 versions of the IMPACT questionnaire with a Likert scale or visual analog scale (VAS), 5 of whom expressed problems with language or phrasing. Difficult words included "restrictions," "moderate," "diarrhea," "school break," and the abbreviation "IBD." Fifteen children preferred the Likert scale to the VAS (chi = 20, P < 0.01). Rewording the difficult words and using a Likert scale should facilitate completion of the IMPACT questionnaire in the United Kingdom. Further validation is needed to ensure that the instrument is reliable and valid.


Assuntos
Doenças Inflamatórias Intestinais/psicologia , Qualidade de Vida , Adolescente , Criança , Colite/psicologia , Colite Ulcerativa/psicologia , Doença de Crohn/psicologia , Feminino , Humanos , Masculino , Projetos Piloto , Perfil de Impacto da Doença , Inquéritos e Questionários , Reino Unido
8.
3 Biotech ; 8(1): 33, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29291146

RESUMO

The tannase production ability by endophytic actinobacteria and the genetic identity of responsible tannase gene were determined. The studied strains were isolated from surface-sterilized leaf discs of Ailanthus excelsa Roxb. Four strains were found to hydrolyze tannic acid on solid media containing 0.4% tannic acid. The strain AL1L was found as tanBLP indicating production of tannase with diverse of substrate affinity. The tannase production from the potential strain AL1L was performed in liquid tannic acid broth (0.4%, w/v). The strain was later identified as Streptomyces sp. AL1L on the basis of 16S rDNA homology. Highest enzyme activity was observed at 48 h of incubation at the exponential growth phase. The enzyme was purified by ammonium sulfate precipitation followed by dialysis (15 kD cut off). This enzyme, with molecular weight 180 kD shows highest catalytic activity at 35 °C, pH 6 with substrate concentration 0.1 g%. The purified enzyme possesses 1.4 × 10-3 Km and 11.15 U/ml as Vmax. The above study indicates high industrial prospective of endophytic actinobacteria as source of tannase of potential biotechnological applications.

9.
J Pediatr Gastroenterol Nutr ; 44(5): 540-54, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17460485

RESUMO

OBJECTIVES: To identify and appraise all studies relating to and instruments developed to measure quality of life (QOL) in children with gastrointestinal or liver diseases. METHODS: A literature search was undertaken using MEDLINE, EMBASE, CINAHL, and PsycINFO to identify relevant articles published up to the end of 2005. These were reviewed by both authors and data were extracted using a standardised form. Articles were excluded if no attempt was made to measure QOL, they did not relate to children ages <17 years, they did not relate to gastrointestinal or liver diseases, or they were review articles. Quality of life instruments identified were rated according to proposed criteria. RESULTS: From a total of 2379 articles identified in the initial search, a total of 2309 were excluded, leaving 70 included studies. These were assigned to the following categories: inflammatory bowel disease, n = 17; cystic fibrosis, n = 20; liver disease, n = 11; surgery, n = 15; and miscellaneous, n = 7. These studies describe the impact that these diseases have on the QOL of affected children. A total of 11 disease-specific QOL instruments and 1 generic instrument with a chronic disease module were identified, but only 5 of these fulfilled the proposed quality criteria and can be recommended for future use. CONCLUSIONS: Chronic gastrointestinal and liver diseases can have an enormous effect on the QOL of affected individuals and their families. A number of disease-specific paediatric QOL instruments have been developed and validated. Quality of life is an important outcome that should be incorporated into clinical practice and measured when treatments are evaluated. Future research should explore how QOL can best be improved in children in whom it is severely impaired.


Assuntos
Gastroenteropatias , Hepatopatias , Qualidade de Vida , Criança , Doença Crônica , Gastroenteropatias/cirurgia , Humanos
10.
Chem Commun (Camb) ; 53(73): 10184-10187, 2017 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-28853453

RESUMO

Hydrocyanines are a class of commonly used reactive oxygen species (ROS) fluorescent imaging probes, which can image ROS in cell culture, organ culture, and in vivo. However, despite their widespread use, hydrocyanines have several drawbacks that limit their effectiveness, such as a high rate of auto-oxidation, a small Stokes shift, and poor water solubility. In addition, the hydrocyanines oxidize into cyanine dyes, which themselves decompose in the presence of ROS, and this further lowers their sensitivity towards detecting ROS. In this report, we present a new hydrocyanine analog, termed as thiophene-bridged hydrocyanine (TBHC), which has its double bonds replaced with a bisthiophene. TBHC is 8.06-fold more stable to auto-oxidation than the hydrocyanine hydro-Cy5 and is significantly better at imaging ROS in cell culture.

11.
Chem Sci ; 8(10): 7143-7151, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-29081945

RESUMO

Aldehyde dehydrogenases (ALDHs) catalyze the oxidation of an aldehyde to a carboxylic acid and are implicated in the etiology of numerous diseases. However, despite their importance, imaging ALDH activity in cells is challenging due to a lack of fluorescent imaging probes. In this report, we present a new family of fluorescent probes composed of an oligothiophene flanked by an aldehyde and an electron donor, termed thiophene-bridged aldehydes (TBAs), which can image ALDH activity in cells. The TBAs image ALDH activity via a fluorescence sensing mechanism based on the modulation of intramolecular charge transfer (ICT) and this enables the TBAs and their ALDH-mediated oxidized products, thiophene-bridged carboxylates (TBCs), to have distinguishable fluorescence spectra. Herein, we show that the TBAs can image ALDH activity in cells via fluorescence microscopy, flow cytometry, and in a plate reader. Using TBA we were able to develop a cell-based high throughput assay for ALDH inhibitors, for the first time, and screened a large, 1460-entry electrophile library against A549 cells. We identified α,ß-substituted acrylamides as potent electrophile fragments that can inhibit ALDH activity in cells. These inhibitors sensitized drug-resistant glioblastoma cells to the FDA approved anti-cancer drug, temozolomide. The TBAs have the potential to make the analysis of ALDH activity in cells routinely possible given their ability to spectrally distinguish between an aldehyde and a carboxylic acid.

12.
Adv Mater ; 28(2): 327-334, 2016 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-26567472

RESUMO

Pore-gradient microgel arrays enable thousands of parallel high-resolution single-cell protein electrophoresis separations for targets accross a wide molecular mass (25-289 kDa), yet within 1 mm separation distances. Dual crosslinked hydrogels facilitate gel-pore expansion after electrophoresis for efficient and uniform immunoprobing. The photopatterned, light-activated, and acid-expandable hydrogel underpins single-cell protein analysis, here for oncoprotein-related signaling in human breast biopsy.


Assuntos
Western Blotting/instrumentação , Hidrogéis , Análise de Célula Única/instrumentação , Western Blotting/métodos , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Eletroforese em Gel de Poliacrilamida/instrumentação , Eletroforese em Gel de Poliacrilamida/métodos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Hidrogéis/química , Hidrogéis/efeitos da radiação , Luz , Proteínas de Transporte Nucleocitoplasmático/metabolismo , Porosidade , Receptor ErbB-2/metabolismo , Análise de Célula Única/métodos , Serina-Treonina Quinases TOR/metabolismo
13.
Chem Commun (Camb) ; 51(88): 15956-9, 2015 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-26377508

RESUMO

In this report we present a polyketal, termed pADK, which has adamantane groups embedded in its backbone, and degrades into neutral excretable compounds. pADK was synthesized via click chemistry and had a MW of 49 472 and a PDI of 1.74. We demonstrate here that pADK can increase the transfection efficiency of CD1800 (PEI of 1800 modified ß-cyclodextrin) 60 fold, yet cause no increase in toxicity.


Assuntos
Adamantano/análogos & derivados , Biotransformação , Éteres/síntese química , Técnicas de Transferência de Genes , Terapia Genética , Polímeros/síntese química , Adamantano/síntese química , Adamantano/metabolismo , Adamantano/toxicidade , Éteres/metabolismo , Éteres/toxicidade , Proteínas de Fluorescência Verde , Células HeLa , Humanos , Polietilenoimina/química , Polímeros/metabolismo , Polímeros/toxicidade , Rodaminas , beta-Ciclodextrinas/química
14.
J Biomed Mater Res A ; 103(1): 76-83, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24616254

RESUMO

Implant-associated inflammation and bacterial infection severely limit the functional performance of medical devices and are a major cause of implant failure. Therefore, it is crucial to develop methodologies to monitor/image implant-associated aseptic inflammation and bacterial infection in a minimally invasive manner. Here, we exploited near-infrared fluorescence (NIRF) molecular probes injected locally at the implant site to perform minimally invasive, simultaneous imaging of inflammation, and infection associated with implanted polymer disks. The hydro-sulfo-Cy5 (H-s-Cy5) probe detected reactive oxygen species associated with inflammatory responses to both aseptic and biofilm-containing implants, whereas diaminocyanine sulfonate selectively detected nitric oxide associated with a biofilm on the biomaterial at acute time points (<4 days). This imaging modality also allows longitudinal monitoring because of high specificity and fast clearance rate of the fluorescent probes. Taken together, these NIRF molecular probes represent a useful tool to directly image inflammatory responses and infections associated with implanted devices for the diagnosis of device-associated inflammation and infection as well as the development of effective therapies.


Assuntos
Materiais Biocompatíveis/efeitos adversos , Inflamação/etiologia , Animais , Biofilmes , Contagem de Colônia Microbiana , Fluorescência , Corantes Fluorescentes , Inflamação/metabolismo , Inflamação/microbiologia , Camundongos , Pseudomonas aeruginosa/isolamento & purificação , Pseudomonas aeruginosa/metabolismo , Espécies Reativas de Oxigênio/metabolismo
15.
Arch Dis Child ; 104(4): 384, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29572219
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