The Influence of Formulation Components and Environmental Humidity on Spray-Dried Phage Powders for Treatment of Respiratory Infections Caused by Acinetobacter baumannii

The feasibility of using respirable bacteriophage (phage) powder to treat lung infections has been demonstrated in animal models and clinical studies. This work investigated the influence of formulation compositions and excipient concentrations on the aerosol performance and storage stability of phage powder. An anti-Acinetobacter baumannii phage vB_AbaM-IME-AB406 was incorporated into dry powders consisting of trehalose, mannitol and L-leucine for the first time. The phage stability upon the spray-drying process, room temperature storage and powder dispersion under different humidity conditions were assessed. In general, powders prepared with higher mannitol content (40% of the total solids) showed a lower degree of particle merging and no sense of stickiness during sample handling. These formulations also provided better storage stability of phage with no further titer loss after 1 month and <1 log titer loss in 6 months at high excipient concentration. Mannitol improved the dispersibility of phage powders, but the in vitro lung dose dropped sharply after exposure to high-humidity condition (65% RH) for formulations with 20% mannitol. While previously collected knowledge on phage powder preparation could be largely extended to formulate A. baumannii phage into inhalable dry powders, the environmental humidity may have great impacts on the stability and dispersion of phage; therefore, specific attention is required when optimizing phage powder formulations for global distribution.

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Correlation of Checkerboard Synergy Testing with Time-Kill Analysis and Clinical Outcomes of Extensively Drug-Resistant Acinetobacter baumannii Respiratory Infections

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00981-16 ◽

2016 ◽

Vol 60 (11) ◽

pp. 6892-6895 ◽

Cited By ~ 12

Author(s):

Derek N. Bremmer ◽

Karri A. Bauer ◽

Stephanie M. Pouch ◽

Keelie Thomas ◽

Debra Smith ◽

...

Keyword(s):

Acinetobacter Baumannii ◽

Clinical Outcomes ◽

Clinical Utility ◽

Respiratory Infections ◽

Drug Resistant ◽

Content Type ◽

Extensively Drug Resistant ◽

Time Kill ◽

Synergy Testing

ABSTRACTWe tested 76 extensively drug-resistant (XDR)Acinetobacter baumanniiisolates by the checkerboard method using only wells containing serum-achievable concentrations (SACs) of drugs. Checkerboard results were correlated by time-kill assay and clinical outcomes. Minocycline-colistin was the best combinationin vitro, as it inhibited growth in one or more SAC wells in all isolates. Patients who received a combination that inhibited growth in one or more SAC wells demonstrated better microbiological clearance than those who did not (88% versus 30%;P= 0.025). The checkerboard platform may have clinical utility for XDRA. baumanniiinfections.

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Black Bean Anthocyanin-Rich Extract from Supercritical and Pressurized Extraction Increased In Vitro Antidiabetic Potential, While Having Similar Storage Stability

Foods ◽

10.3390/foods9050655 ◽

2020 ◽

Vol 9 (5) ◽

pp. 655 ◽

Cited By ~ 1

Author(s):

Ming Hsieh-Lo ◽

Gustavo Castillo-Herrera ◽

Luis Mojica

Keyword(s):

Phenolic Compounds ◽

Storage Stability ◽

Ultra Performance Liquid Chromatography ◽

Syringic Acid ◽

Total Phenolic ◽

Black Bean ◽

Flight Mass Spectrometry ◽

Biological Potential ◽

The Stability

Black bean is a source of anthocyanins and other phenolic compounds that are associated with health benefits. This work aimed to optimize the extraction and determine the stability and biological potential of black bean anthocyanin-rich extracts recovered by supercritical fluid extraction (SFE) and pressurized liquid extraction (PLE). The highest concentration of anthocyanins and total phenolic compounds were recovered with SFE using 300 bar, 60 °C and co-solvent ethanol/distilled water (50/50, v/v). Eleven non-colored phenolic compounds were identified in SFE extract using Ultra performance liquid chromatography - Electrospray ionization–Quadrupole -Time of flight - Mass spectrometry (UPLC-ESI-QToF-MS/MS). Myricetin, syringic acid, rutin hydrate and chlorogenic acid presented the highest relative area among identified compounds. Compared to leaching extraction, SFE extracts showed a similar storage stability at 4, 25 and 32 °C (p < 0.05), but with a higher antioxidant potential (2,2-diphenyl-1-picryl-hydrazil (DPPH) IC50: 0.078 ± 0.01; 2,2’-azino-bis(3-ethylbenzothiazoline)-6-sulfonic acid (ABTS) IC50: 0.161 ± 0.03) and antidiabetic potential (α-amylase IC50: 124.76 ± 12.97; α-glucosidase IC50: 31.30 ± 0.84; dipeptidyl peptidase-IV IC50: 0.195 ± 0.01). SFE extraction is an efficient method to obtain anthocyanins and other phenolic compounds with exceptional biological potential.

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Multiple Fungicide Resistance in Botrytis cinerea from Greenhouse Strawberries in Hubei Province, China

Plant Disease ◽

10.1094/pdis-09-16-1227-re ◽

2017 ◽

Vol 101 (4) ◽

pp. 601-606 ◽

Cited By ~ 30

Author(s):

F. Fan ◽

M. S. Hamada ◽

N. Li ◽

G. Q. Li ◽

C. X. Luo

Keyword(s):

Botrytis Cinerea ◽

Management Strategies ◽

Hubei Province ◽

Early Summer ◽

Initial Generation ◽

Succinate Dehydrogenase Subunit B ◽

The Stability ◽

First Time

Two hundred and forty isolates of Botrytis cinerea were collected during the early summer of 2012 and 2013 from strawberry greenhouses in 10 locations in Hubei Province and examined for sensitivity to five fungicides, most of which were commonly used to control this fungus. High frequency of resistance to carbendazim (Car, 63.63%) and cyprodinil (Cyp, 42.42%) was detected. Boscalid-resistant (BosR) isolates were detected for the first time in China, whereas no fludioxonil-resistant isolates were identified. Dual resistance to carbendazim and diethofencarb (Die) was also detected. There were six phenotypes of resistance profile (i.e., CarRDieSBosSCypS, CarRDieRBosSCypS, CarRDieSBosSCypR, CarRDieSBosRCypS, CarRDieRBosSCypR, and CarRDieSBosRCypR). CarRDieSBosSCypS and CarRDieSBosSCypR were the most common phenotypes, occurring at eight and seven locations, respectively. After 10 successive transfers on fungicide-free potato dextrose agar, tested resistant isolates retained levels of resistance similar to or comparative with the initial generation, indicating the stability of these resistances. Fitness evaluations based on investigation of mycelial growth, osmotic sensitivity, sporulation in vitro and in vivo, and virulence revealed the uncompromising fitness in resistant isolates, except that decreased virulence was observed in BosR isolates. The molecular basis of carbendazim, diethofencarb, and boscalid resistance was investigated. Results showed that all 13 sequenced carbendazim-resistant isolates harbored the mutation E198V or E198A in the β-tubulin gene and the five isolates with dual resistance to carbendazim and diethofencarb showed the mutation E198K in the same gene. BosR isolates possessed the H272R mutation in succinate dehydrogenase subunit B gene. The results achieved in this study challenge the current management strategies for B. cinerea, which largely depend on applications of these fungicides.

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The effect of excipients on the stability and aerosol performance of salmon calcitonin dry powder inhalers prepared via the spray freeze drying process

Acta Pharmaceutica ◽

10.1515/acph-2016-0012 ◽

2016 ◽

Vol 66 (2) ◽

pp. 207-218 ◽

Cited By ~ 8

Author(s):

Narges Poursina ◽

Alireza Vatanara ◽

Mohammad Reza Rouini ◽

Kambiz Gilani ◽

Abdolhossein Rouholamini Najafabadi

Keyword(s):

Salmon Calcitonin ◽

Freeze Drying ◽

Tween 80 ◽

Drying Process ◽

Dry Powders ◽

Aerosol Performance ◽

Inhalation Delivery ◽

Spray Freeze Drying ◽

The Stability ◽

Structurally Stable

Abstract Spray freeze drying was developed to produce dry powders suitable for applications such as inhalation delivery. In the current study, the spray freeze drying technique was employed to produce inhalable salmon calcitonin microparticles. Effects of the carrier type, concentration of hydroxyl propyl-β-cyclodextrin and the presence of Tween 80 on the chemical and structural stability, as well as on the aerosol performance of the particles were investigated. The results indicated that hydroxyl propyl-β-cyclodextrin had the most important effect on the chemical stability of the powder and strongly increased its stability by increasing its concentration in the formulation. Chemically stable formulations (over 90 % recovery) were selected for further examinations. Fluorescence spectroscopy and circular dichroism suggested that the formulations were structurally stable. Aerosol performance showed that the Tween-free powders produced higher fine particle fraction values than the formulations containing Tween (53.7 vs. 41.92 % for trehalose content and 52.85 vs. 43.06 % for maltose content).

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In Vivo Validation of Peptidoglycan Recycling as a Target to Disable AmpC-Mediated Resistance and Reduce Virulence Enhancing the Cell-Wall–Targeting Immunity

The Journal of Infectious Diseases ◽

10.1093/infdis/jiz377 ◽

2019 ◽

Vol 220 (11) ◽

pp. 1729-1737 ◽

Cited By ~ 4

Author(s):

Gabriel Torrens ◽

Irina Sánchez-Diener ◽

Elena Jordana-Lluch ◽

Isabel María Barceló ◽

Laura Zamorano ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Cell Wall ◽

Respiratory Infections ◽

Bacterial Load ◽

Murine Models ◽

Promising Therapeutic Target ◽

One Step ◽

First Time

Abstract Background Searching for new strategies to defeat Pseudomonas aeruginosa is of paramount importance. Previous works in vitro showed that peptidoglycan recycling blockade disables AmpC-dependent resistance and enhances susceptibility against cell-wall–targeting immunity. Our objective was to validate these findings in murine models. This study shows for the first time in different murine models of infection that blocking the peptidoglycan recycling in Pseudomonas aeruginosa causes an important virulence impairment and disables AmpC-mediated resistance, being hence validated as a promising therapeutic target. Methods Wildtype PAO1, recycling-defective AmpG and NagZ mutants, an AmpC hyperproducer dacB mutant, and their combinations were used to cause systemic/respiratory infections in mice. Their survival, bacterial burden, inflammation level, and effectiveness of ceftazidime or subtherapeutic colistin to treat the infections were assessed. Results Inactivation of AmpG or NagZ significantly attenuated the virulence in terms of mice mortality, bacterial load, and inflammation. When inactivating these genes in the dacB-defective background, the β-lactam resistance phenotype was abolished, disabling the emergence of ceftazidime-resistant mutants, and restoring ceftazidime for treatment. Subtherapeutic colistin was shown to efficiently clear the infection caused by the recycling-defective strains, likely due to the combined effect with the mice cell-wall– targeting immunity. Conclusions This study brings us one step closer to new therapies intended to disable P. aeruginosa AmpC-mediated resistance and dampen its virulence, and strongly support the interest in developing efficient AmpG and/or NagZ inhibitors.

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The First Selenoanhydride in the Series of Chlorophyll a Derivatives, Its Stability and Photoinduced Cytotoxicity

Molecules ◽

10.3390/molecules26237298 ◽

2021 ◽

Vol 26 (23) ◽

pp. 7298

Author(s):

Viktor Pogorilyy ◽

Anna Plyutinskaya ◽

Nikita Suvorov ◽

Ekaterina Diachkova ◽

Yuriy Vasil’ev ◽

...

Keyword(s):

Spectral Properties ◽

Quantum Yields ◽

Chalcogen Atom ◽

Target Compound ◽

Ph Values ◽

High Fluorescence ◽

The Stability ◽

First Time ◽

Chlorin P6

In this work, we obtained the first selenium-containing chlorin with a chalcogen atom in exlocycle E. It was shown that the spectral properties were preserved in the target compound and the stability increased at two different pH values, in comparison with the starting purpurin-18. The derivatives have sufficiently high fluorescence and singlet oxygen quantum yields. The photoinduced cytotoxicity of sulfur- and selenium-anhydrides of chlorin p6 studied for the first time in vitro on the S37 cell line was found to be two times higher that of purpurin-18 and purpurinimide studied previously. Moreover, the dark cytotoxicity increased four-fold in comparison with the latter compounds. Apparently, the increase in the dark cytotoxicity is due to the interaction of the pigments studied with sulfur- and selenium-containing endogenous intracellular compounds. Intracellular distributions of thioanhydride and selenoanhydride chlorin p6 in S37 cells were shown in cytoplasm by diffusion distribution. The intracellular concentration of the sulfur derivative turned out to be higher and, as a consequence, its photoinduced cytotoxicity was higher as well.

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LncRNA CRNDE Promotes ATG4B-Mediated Autophagy and Alleviates the Sensitivity of Sorafenib in Hepatocellular Carcinoma Cells

Frontiers in Cell and Developmental Biology ◽

10.3389/fcell.2021.687524 ◽

2021 ◽

Vol 9 ◽

Author(s):

Lingxi Chen ◽

Liangbo Sun ◽

Xufang Dai ◽

Tao Li ◽

Xiaojing Yan ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Colorectal Neoplasia ◽

Promoting Effect ◽

Non Coding Rna ◽

Novel Target ◽

The Stability ◽

First Time ◽

Hcc Cells

Autophagy is closely related to the growth and drug resistance of cancer cells, and autophagy related 4B (ATG4B) performs a crucial role in the process of autophagy. The long non-coding RNA (lncRNA) colorectal neoplasia differentially expressed (CRNDE) promotes the progression of hepatocellular carcinoma (HCC), but it is unclear whether the tumor-promoting effect of CRNDE is associated with the regulation of ATG4B and autophagy. Herein, we for the first time demonstrated that CRNDE triggered autophagy via upregulating ATG4B in HCC cells. Mechanistically, CRNDE enhanced the stability of ATG4B mRNA by sequestrating miR-543, leading to the elevation of ATG4B and autophagy in HCC cells. Moreover, sorafenib induced CRNDE and ATG4B as well as autophagy in HCC cells. Knockdown of CRNDE sensitized HCC cells to sorafenib in vitro and in vivo. Collectively, these results reveal that CRNDE drives ATG4B-mediated autophagy, which attenuates the sensitivity of sorafenib in HCC cells, suggesting that the pathway CRNDE/ATG4B/autophagy may be a novel target to develop sensitizing measures of sorafenib in HCC treatment.

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Study of stability of proline-containing derivatives of dopamine and serotonin in the biological media in vitro experiments

Biomeditsinskaya Khimiya ◽

10.18097/pbmc20196506498 ◽

2019 ◽

Vol 65 (6) ◽

pp. 498-506 ◽

Cited By ~ 1

Author(s):

K.V. Shevchenko ◽

L.A. Andreeva ◽

I.Yu. Nagaev ◽

V.P. Shevchenko ◽

N.F. Myasoedov

Keyword(s):

Leucine Aminopeptidase ◽

Biologically Active ◽

Carboxypeptidase Y ◽

Vital Activity ◽

Prolonged Action ◽

Carboxypeptidase B ◽

The Stability ◽

First Time ◽

Derivatives Of

Boc-Gly-Pro-DP, Z-Gly-Pro-DP, LA-Gly-Pro-DP, Boc-Gly-Pro-Srt, Z-Gly-Pro-Srt were synthesized for the first time. The stability of these compounds in the presence of leucine aminopeptidase, carboxypeptidase Y, carboxypeptidase B and proline endopeptidase (PEP) was determined. It turned out that the compounds are stable in the presence of aminopeptidases and carboxypeptidases. In the presence of PEP, dopamine (DP) and serotonin (Srt) are cleaved from the synthesized preparations. Thus, new proline-containing Srt and DP derivatives were obtained, Srt and DP could be gradually released from them. This suggest the possibility of a prolonged action of these biologically active compounds on the vital activity of cells and, consequently, of the whole organism.

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Genotoxic Properties of Synthetic Cannabinoids on TK6 Human Cells by Flow Cytometry

International Journal of Molecular Sciences ◽

10.3390/ijms21031150 ◽

2020 ◽

Vol 21 (3) ◽

pp. 1150 ◽

Cited By ~ 3

Author(s):

Monia Lenzi ◽

Veronica Cocchi ◽

Luca Cavazza ◽

Sabrine Bilel ◽

Patrizia Hrelia ◽

...

Keyword(s):

Flow Cytometry ◽

Synthetic Cannabinoids ◽

Genetic Material ◽

Fold Increase ◽

Mutagenic Effect ◽

Long Term Effects ◽

The Stability ◽

Tk6 Cells ◽

First Time

Novel Psychoactive Substances (NPS) include several classes of substances such as synthetic cannabinoids (SCBs), an emerging alternative to marijuana, easily purchasable on internet. SCBs are more dangerous than Δ9-Tetrahydrocannabinol as a consequence of their stronger affinities for the CB1 and CB2 receptors, which may result in longer duration of distinct effects, greater potency, and toxicity. The information on SCBs cytotoxicity, genotoxicity, mutagenicity, and long-term effects is scarce. This fact suggests the urgent need to increase available data and to investigate if some SCBs have an impact on the stability of genetic material. Therefore, the aim of the present study was the evaluation of the mutagenic effect of different SCBs belonging to indole- and indazole-structures. The analyzes were conducted in vitro on human TK6 cells and mutagenicity were measured as micronucleus fold increase by flow cytometry. Our results have highlighted, for the first time, the mutagenic capacity of four SCBs, in particular in terms of chromosomal damage induction. We underline the serious potential toxicity of SCBs that suggests the need to proceed with the studies of other different synthetic compounds. Moreover, we identified a method that allows a rapid but effective screening of NPS placed on the market increasingly faster.

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In Vitro Activity and In Vivo Efficacy of Clavulanic Acid against Acinetobacter baumannii

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00320-09 ◽

2009 ◽

Vol 53 (10) ◽

pp. 4298-4304 ◽

Cited By ~ 7

Author(s):

Alejandro Beceiro ◽

Rafael López-Rojas ◽

Juan Domínguez-Herrera ◽

Fernando Docobo-Pérez ◽

Germán Bou ◽

...

Keyword(s):

Acinetobacter Baumannii ◽

Clavulanic Acid ◽

Control Group ◽

In Vitro Activity ◽

Untreated Control Group ◽

Time Kill ◽

First Time ◽

Bacterial Concentrations

ABSTRACT Clavulanic acid (CLA) exhibits low MICs against some Acinetobacter baumannii strains. The present study evaluates the efficacy of CLA in a murine model of A. baumannii pneumonia. For this purpose, two clinical strains, Ab11 and Ab51, were used; CLA MICs for these strains were 2 and 4 mg/liter, respectively, and the imipenem (IPM) MIC was 0.5 mg/liter for both. A pneumonia model in C57BL/6 mice was used. The CLA dosage (13 mg/kg of body weight given intraperitoneally) was chosen to reach a maximum concentration of the drug in serum similar to that in humans and a time during which the serum CLA concentration remained above the MIC equivalent to 40% of the interval between doses. Six groups (n = 15) were inoculated with Ab11 or Ab51 and were allocated to IPM or CLA therapy or to the untreated control group. In time-kill experiments, CLA was bactericidal only against Ab11 whereas IPM was bactericidal against both strains. CLA and IPM both decreased bacterial concentrations in lungs, 1.78 and 2.47 log10 CFU/g (P ≤ 0.001), respectively, in the experiments with Ab11 and 2.42 and 2.28 log10 CFU/g (P ≤ 0.001), respectively, with Ab51. IPM significantly increased the sterility of blood cultures over that for the controls with both strains (P ≤ 0.005); CLA had the same effect with Ab51 (P < 0.005) but not with Ab11 (P = 0.07). For the first time, we suggest that CLA may be used for the treatment of experimental severe A. baumannii infections.

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