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1.
Reprod Biomed Online ; 48(4): 103734, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38359733

RESUMO

Disruption of women's gut and cervicovaginal microbiota has been associated with multiple gynaecological diseases such as endometriosis, polycystic ovary syndrome, non-cyclic pelvic pain and infertility. Female infertility affects 12.6% of women worldwide; its aetiology is complex and multifactorial and can be underpinned by uterine pathologies, systemic diseases and age. In addition, a new perspective has emerged on the role of the gut and vaginal microbiomes in reproductive health. Research shows that the administration of precisely selected probiotics, often in combination with prior antibiotic treatment, may facilitate the restoration of symbiotic microbiota to increase successful conception and assisted reproductive technology outcomes. However, clarity on this issue from fuller research is currently hampered by a lack of consistency and harmonization in clinical studies: various lactobacilli and bifidobacteria species have been delivered through both the oral and vaginal routes, in different dosages, for different treatment durations. This commentary explores the intricate relationship between the microbiota in the cervicovaginal area and gut of women, exploring their potential contribution to infertility. It highlights ongoing research on the use of probiotic formulations in improving pregnancy outcomes, critically examining the divergent findings in these studies, which complicate a conclusive assessment of the efficacy of these interventions.


Assuntos
Endometriose , Infertilidade Feminina , Probióticos , Gravidez , Feminino , Humanos , Infertilidade Feminina/terapia , Infertilidade Feminina/etiologia , Vagina/microbiologia , Resultado da Gravidez , Endometriose/complicações , Probióticos/uso terapêutico
2.
Mol Pharm ; 19(5): 1477-1487, 2022 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-35347993

RESUMO

Flufenamic acid (FFA) is a highly polymorphic drug molecule with nine crystal structures reported in the Cambridge Structural Database. This study explores the use of synchrotron X-ray powder diffraction combined with differential scanning calorimetry to study crystallization and polymorphic phase transitions upon heating FFA-polymer amorphous solid dispersions (ASDs). Ethyl cellulose (EC, 4 cp) and hydroxypropylmethylcellulose (HPMC) grades with different viscosities and substitution patterns were used to prepare dispersions with FFA at 5:1, 2:1, 1:1, and 1:5 w/w drug/polymer ratios by quench cooling. We employed a 6 cp HPMC 2910 material and two HPMC 2208 samples at 4000 and 100 000 cp. Hyphenated X-ray diffraction (XRD)-differential scanning calorimetry (DSC) studies show that the 6 and 100 000 cp HPMCs and 4 cp EC polymers can stabilize FFA form IV by inhibiting the transition to form I during heating. It appears that the polymers stabilize FFA in both amorphous and metastable forms via a combination of intermolecular interactions and viscosity effects. Increasing the polymer content of the ASD also inhibits polymorphic transitions, with drug/polymer ratios of 1:5 w/w resulting in FFA remaining amorphous during heating. The comparison of FFA ASDs prepared with different samples of HPMCs and ECs suggests that the chemical substitution of the polymer (HPMC 2208 has 19-24% methoxy groups and 4-12% hydroxypropyl groups, while HPMC 2910 has 28-30% methoxy groups and 7-12% hydroxypropyl groups) plays a more significant role in directing polymorphic transitions than the viscosity. A previously unreported polymorph of FFA was also noted during heating but its structure could not be determined.


Assuntos
Ácido Flufenâmico , Polímeros , Varredura Diferencial de Calorimetria , Derivados da Hipromelose/química , Polímeros/química , Solubilidade , Difração de Raios X
3.
Chemistry ; 26(64): 14645-14653, 2020 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-32706515

RESUMO

Co-crystallisation is widely explored as a route to improve the physical properties of pharmaceutical active ingredients, but little is known about the fundamental mechanisms of the process. Herein, we apply a hyphenated differential scanning calorimetry-X-ray diffraction technique to mimic the commercial hot melt extrusion process, and explore the heat-induced synthesis of a series of new co-crystals containing isonicotinamide. These comprise a 1:1 co-crystal with 4-hydroxybenzoic acid, 2:1 and 1:2 systems with 4-hydroxyphenylacetic acid and a 1:1 crystal with 3,4-dihydroxyphenylactic acid. The formation of co-crystals during heating is complex mechanistically. In addition to co-crystallisation, conversions between polymorphs of the co-former starting materials and co-crystal products are also observed. A subsequent study exploring the use of inkjet printing and milling to generate co-crystals revealed that the synthetic approach has a major effect on the co-crystal species and polymorphs produced.

4.
Mol Pharm ; 17(11): 4364-4374, 2020 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-33074007

RESUMO

Amorphous solid dispersions (ASDs) of class II and IV biopharmaceutics classification system drugs in water-miscible polymers are a well-recognized means of enhancing dissolution, while such dispersions in hydrophobic polymers form the basis of micro- and nanoparticulate technologies. However, drug recrystallization presents significant problems for product development, and the mechanisms and pathways involved are poorly understood. Here, we outline the use of combined differential scanning calorimetry (DSC)-synchrotron X-ray diffraction to monitor the sequential appearance of polymorphs of olanzapine (OLZ) when dispersed in a range of polymers. In a recent study (Cryst. Growth Des.2019,19, 2751-2757), we reported a new polymorph (form IV) of OLZ which crystallized from a spray-dried dispersion of OLZ in polyvinylpyrrolidone. Here, we extend our earlier study to explore OLZ dispersions in poly(lactide-co-glycolide) (PLGA), polylactide (PLA), and hydroxypropyl methyl cellulose acetate succinate (HPMCAS), with a view to identifying the sequence of form generation on heating each dispersion. While spray-dried OLZ results in the formation of crystalline form I, the spray-dried material with HPMCAS comprises an ASD, and forms I and IV are generated upon heating. PLGA and PLA result in a product which contains both amorphous OLZ and the dichloromethane solvate; upon heating, the amorphous material converts to forms I, II, and IV and the solvate to forms I and II. Our data show that it is possible to quantitatively assess not only the polymorph generation sequence but also the relative proportions as a function of temperature. Of particular note is that the sequence of form generation is significantly more complex than may be indicated by DSC data alone, with coincident generation of different polymorphs and complex interconversions as the material is heated. We argue that this may have implications not only for the mechanistic understanding of polymorph generation but also as an aid to identifying the range of polymorphic forms that may be produced by a single-drug molecule.


Assuntos
Varredura Diferencial de Calorimetria/métodos , Composição de Medicamentos/métodos , Metilcelulose/análogos & derivados , Olanzapina/química , Poliésteres/química , Poliglactina 910/química , Difração de Raios X/métodos , Química Farmacêutica/métodos , Cristalização , Liberação Controlada de Fármacos , Temperatura Alta , Interações Hidrofóbicas e Hidrofílicas , Metilcelulose/química , Solubilidade
5.
Pharm Res ; 36(7): 102, 2019 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-31098846

RESUMO

PURPOSE: The use of three-dimensional printing (3DP) in the development of pharmaceutical dosage forms is growing rapidly. However, the research is almost exclusively focussed on polymer-based systems with very little reported on 3D printing of lipid-based formulations. Thus, the aim of the work was to explore the feasibility of 3DP technology to prepare solid lipid-based formulations. Here, 3DP was applied for the preparation of solid self-microemulsifying drug delivery systems (S-SMEDDS) with defined surface area to volume (SA/V) ratios. METHODS: The S-SMEDDS formulations, comprised of Gelucire® 44/14, Gelucire® 48/16 and Kolliphor® P 188 were loaded with fenofibrate or cinnarizine as model drugs. The formulations were printed into four geometrical shapes - cylindrical, prism, cube and torus, and compared to a control cube manually prepared from bulk formulation. RESULTS: The printing process was not significantly affected by the presence of the model drugs. The as-printed S-SMEDDS formulations were characterised using differential scanning calorimetry and wide-angle X-ray scattering. The kinetics of dispersion depended on the SA/V ratio values. The digestion process was affected by the initial geometry of the dosage form by virtue of the kinetics of dispersion of the dosage forms into the digestion medium. CONCLUSIONS: This proof of concept study has demonstrated the potential of 3DP for the development of customised S-SMEDDS formulations without the need for an additional carrier or additive and with optimisation could elaborate a new class of dosage forms based on 3D printed lipids. Graphical abstract Lipid based formulations were 3D printed in various shapes to control the surface are to volume ratio and consequently the kinetics of dispersion.


Assuntos
Cinarizina/farmacologia , Portadores de Fármacos/química , Fenofibrato/farmacologia , Lipídeos/química , Impressão Tridimensional , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Cinética , Polietilenoglicóis/química , Estudo de Prova de Conceito , Solubilidade , Tensoativos/química , Água
6.
World J Microbiol Biotechnol ; 35(3): 49, 2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-30840154

RESUMO

Cell free supernatants (CFS) obtained from probiotic species are routinely used to preliminary investigate the antimicrobial activity of potential probiotic isolates by the agar well diffusion and broth culture. Both methods have documented limitations. In this work, the potential of isothermal microcalorimetry (IMC), a technique based on the measurement of heat produced by growing bacteria was used to investigate the antimicrobial effects of two commercial probiotic species (Lactobacillus acidophilus LA-5® and Bifidobacterium lactis BB-12®) and one reference strain (Bifidobacterium bifidum ATCC 11863) against Pseudomonas aeruginosa NCIMB 8628 using unmodified, neutralised and heat-treated CFS. P. aeruginosa was inhibited in growth by the unmodified CFS of all the species. No inhibitory activity was recorded for neutralised CFS of all the species using the agar well diffusion assay. Plate count during co-incubation of P. aeruginosa with the neutralised CFS of all the species showed no inhibition. However, IMC data showed significant inhibition with neutralised CFS obtained from the two Bifidobacterium species suggesting presence of other non-acidic inhibitory compounds in the CFS. The results in this work demonstrated that IMC has potential in probiotic bioassay as it has the capability to record in real-time and capture even subtle effects, which could be unnoticed with traditional assays.


Assuntos
Técnicas Bacteriológicas/métodos , Calorimetria/métodos , Testes de Sensibilidade Microbiana/métodos , Probióticos/metabolismo , Probióticos/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Ágar , Anti-Infecciosos/metabolismo , Anti-Infecciosos/farmacologia , Bifidobacterium , Bifidobacterium animalis/metabolismo , Bifidobacterium bifidum/metabolismo , Meios de Cultura , Concentração de Íons de Hidrogênio , Lactobacillus acidophilus/metabolismo , Pseudomonas aeruginosa/crescimento & desenvolvimento
7.
Chemistry ; 24(51): 13573-13581, 2018 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-29979477

RESUMO

Temperature-induced phase transitions in carbamazepine (CBZ) and 10,11-dihydrocarbamazepine (DHC) were studied by simultaneous differential scanning calorimetry-X-ray diffraction in this work. The transitions generally involve a transitional melt phase which is quickly followed by recrystallisation. The expansions of the unit cell as a function of temperature could be quantified and allow us to determine a directional order of stability in relation to the lattice constants. Dihydrocarbamazepine form II undergoes a conversion to form I by a localised melt phase. Carbamazepine (CBZ) form IV converts to form I at 182 °C, again by a localised intermediate melt phase. CBZ form II converted to form I at 119 °C by a pathway that appears to have included some melting, and form III underwent a part melt-recrystallisation and a part sublimation-recrystallisation to form I.


Assuntos
Carbamazepina/análogos & derivados , Carbamazepina/química , Transição de Fase , Varredura Diferencial de Calorimetria , Cristalização , Congelamento , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Estrutura Molecular , Polimerização , Solubilidade , Temperatura
8.
Mol Pharm ; 15(8): 3332-3342, 2018 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-29933697

RESUMO

The assessment of drug-polymer equilibrium solubility is of critical importance for predicting suitable loading and physical stability of solid dispersion formulations. However, quantitative measurement of this parameter is nontrivial due to the difficulties associated with ascertaining equilibrium values in systems that are prone to supersaturation and are simultaneously highly viscous, thereby slowing the equilibration process considerably; no standard methodology has yet been agreed for such measurements. In this study, we propose a new approach involving quasi-isothermal modulated temperature DSC (QiMTDSC), whereby unsaturated and supersaturated samples are held at defined temperatures and subject to a sinusoidal heating signal at a zero underpinning heating rate, thereby allowing the heat capacity of the sample to be measured as a function of time and temperature. We are not only able to ascertain whether equilibrium has been reached by monitoring the time-dependent heat capacity signal, but we can also measure solubility as a function of temperature via the absolute heat capacity values of the components. We are also able to measure the kinetics of recrystallization from the supersaturated systems. Dispersions of olanzapine in PLGA at concentrations up to 50% w/w, prepared by spray drying, were prepared and characterized using conventional and QiMTDSC as well as hot stage microscopy. The new QiMTDSC protocol was successfully able to determine olanzapine solubility in PLGA at 90 °C to be 23.1 ± 6.1% w/w, which was comparable to the values calculated using other established methods at this temperature, while a temperature/solubility profile was obtained using the method at a range of temperatures. Drug crystallization kinetics from the solid dispersions could also be modeled directly from the QiMTDSC data using the Avrami approach, thereby allowing the effect of drug loading on the rate of crystallization and the effective completion of crystallization to be investigated. Overall, an alternative protocol for measuring drug-polymer solubility has been developed and validated via comparison to established methods, the approach allowing solubility as a function of temperature, identification of equilibrium following demixing, and kinetic analysis of crystallization to be performed within one set of experiments.


Assuntos
Varredura Diferencial de Calorimetria/métodos , Química Farmacêutica/métodos , Olanzapina/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Cristalização , Preparações de Ação Retardada/química , Composição de Medicamentos/métodos , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Temperatura Alta/efeitos adversos , Cinética , Micelas , Solubilidade
9.
Soft Matter ; 14(22): 4615-4620, 2018 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-29786736

RESUMO

Herein, we report on the phase behaviour of a binary liquid mixture composed of methanol (MeOH) and the thermotropic liquid crystal 4-cyano-4'-pentylbiphenyl (5CB). The corresponding phase diagram combines features of a conventional liquid-liquid mixture with characteristics that are particular to the nematic liquid crystal. We observe four arrangements as a function of composition and temperature, namely monophasic isotropic, monophasic nematic, biphasic isotropic-isotropic and biphasic isotropic-nematic, with an upper critical solution temperature of 24.4 ± 0.5 °C. The interplay of nematogenic and non-nematogenic species offers tunability of phase mixing and phase composition in an accessible temperature window and provides novel routes for the extraction of target compounds, here exemplarily shown for Crystal Violet, Doxorubicin, Eosin Y, Rhodamine 6G and Sudan IV.

10.
Pharm Res ; 36(1): 4, 2018 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-30406349

RESUMO

PURPOSE: Three-dimensional printing (3DP) is a rapidly growing additive manufacturing process and it is predicted that the technology will transform the production of goods across numerous fields. In the pharmaceutical sector, 3DP has been used to develop complex dosage forms of different sizes and structures, dose variations, dose combinations and release characteristics, not possible to produce using traditional manufacturing methods. However, the technology has mainly been focused on polymer-based systems and currently, limited information is available about the potential opportunities for the 3DP of soft materials such as lipids. METHODS: This review paper emphasises the most commonly used 3DP technologies for soft materials such as inkjet printing, binder jetting, selective laser sintering (SLS), stereolithography (SLA), fused deposition modeling (FDM) and semi-solid extrusion, with the current status of these technologies for soft materials in biological, food and pharmaceutical applications. RESULT: The advantages of 3DP, particularly in the pharmaceutical field, are highlighted and an insight is provided about the current studies for lipid-based drug delivery systems evaluating the potential of 3DP to fabricate innovative products. Additionally, the challenges of the 3DP technologies associated with technical processing, regulatory and material issues of lipids are discussed in detail. CONCLUSION: The future utility of 3DP for printing soft materials, particularly for lipid-based drug delivery systems, offers great advantages and the technology will potentially support patient compliance and drug effectiveness via a personalised medicine approach.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Lipídeos/química , Humanos , Nanopartículas/química , Polímeros/química , Medicina de Precisão/métodos , Impressão Tridimensional
11.
AAPS PharmSciTech ; 19(8): 3355-3361, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29948979

RESUMO

Additive manufacturing (3D printing) permits the fabrication of tablets in shapes unattainable by powder compaction, and so the effects of geometry on drug release behavior is easily assessed. Here, tablets (printlets) comprising of paracetamol dispersed in polyethylene glycol were printed using stereolithographic 3D printing. A number of geometric shapes were produced (cube, disc, pyramid, sphere and torus) with either constant surface area (SA) or constant surface area/volume ratio (SA/V). Dissolution testing showed that printlets with constant SA/V ratio released drug at the same rate, while those with constant SA released drug at different rates. A series of tori with increasing SA/V ratio (from 0.5 to 2.4) were printed, and it was found that dissolution rate increased as the SA/V ratio increased. The data show that printlets can be fabricated in multiple shapes and that dissolution performance can be maintained if the SA/V ratio is constant or that dissolution performance of printlets can be fine-tuned by varying SA/V ratio. The results suggest that 3D printing is therefore a suitable manufacturing method for personalized dosage forms.


Assuntos
Liberação Controlada de Fármacos , Estereolitografia , Comprimidos/química , Tecnologia Farmacêutica/métodos , Acetaminofen/química , Polietilenoglicóis/química , Pós , Impressão Tridimensional
12.
Anal Chem ; 88(20): 10111-10117, 2016 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-27642771

RESUMO

We report a powerful new technique: hyphenating synchrotron X-ray powder diffraction (XRD) with differential scanning calorimetry (DSC). This is achieved with a simple modification to a standard laboratory DSC instrument, in contrast to previous reports which have involved extensive and complex modifications to a DSC to mount it in the synchrotron beam. The high-energy X-rays of the synchrotron permit the recording of powder diffraction patterns in as little as 2 s, meaning that thermally induced phase changes can be accurately quantified and additional insight on the nature of phase transitions obtained. Such detailed knowledge cannot be gained from existing laboratory XRD instruments, since much longer collection times are required. We demonstrate the power of our approach with two model systems, glutaric acid and sulfathiazole, both of which show enantiotropic polymorphism. The phase transformations between the low and high temperature polymorphs are revealed to be direct solid-solid processes, and sequential refinement against the diffraction patterns obtained permits phase fractions at each temperature to be calculated and unit cell parameters to be accurately quantified as a function of temperature. The combination of XRD and DSC has further allowed us to identify mixtures of phases which appeared phase-pure by DSC.


Assuntos
Varredura Diferencial de Calorimetria/métodos , Glutaratos/química , Difração de Pó/métodos , Sulfatiazóis/química , Difração de Raios X/métodos , Transição de Fase , Estereoisomerismo , Sulfatiazol , Temperatura
13.
Methods ; 76: 35-40, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25498003

RESUMO

Isothermal microcalorimetry (IMC) is particularly suited to the study of microbiological samples in complex or heterogeneous environments because it does not require optical clarity of the sample and can detect metabolic activity from as few as 10(4) CFU/mL cells. While the use of IMC for studying planktonic cultures is well established, in the clinical environment bacteria are most likely to be present as biofilms. Biofilm prevention and eradication present a number of challenges to designers and users of medical devices and implants, since bacteria in biofilm colonies are usually more resistant to antimicrobial agents. Analytical tools that facilitate investigation of biofilm formation are therefore extremely useful. While it is possible to study pre-prepared biofilms in closed ampoules, better correlation with in vivo behaviour can be achieved using a system in which the bacterial suspension is flowing. Here, we discuss the potential of flow microcalorimetry for studying biofilms and report the development of a simple flow system that can be housed in a microcalorimeter. The use of the flow system is demonstrated with biofilms of Staphylococcus aureus.


Assuntos
Biofilmes/crescimento & desenvolvimento , Calorimetria/métodos , Equipamentos e Provisões/microbiologia , Staphylococcus aureus/fisiologia , Microscopia Eletrônica de Varredura , Staphylococcus aureus/ultraestrutura
14.
Mol Pharm ; 12(11): 4077-84, 2015 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-26473653

RESUMO

Three dimensional printing (3D printing) was used to fabricate novel oral drug delivery devices with specialized design configurations. Each device was loaded with multiple actives, with the intent of applying this process to the production of personalized medicines tailored at the point of dispensing or use. A filament extruder was used to obtain drug-loaded--paracetamol (acetaminophen) or caffeine--filaments of poly(vinyl alcohol) with characteristics suitable for use in fused-deposition modeling 3D printing. A multinozzle 3D printer enabled fabrication of capsule-shaped solid devices containing the drug with different internal structures. The design configurations included a multilayer device, with each layer containing drug, whose identity was different to the drug in the adjacent layers, and a two-compartment device comprising a caplet embedded within a larger caplet (DuoCaplet), with each compartment containing a different drug. Raman spectroscopy was used to collect 2-dimensional hyper spectral arrays across the entire surface of the devices. Processing of the arrays using direct classical least-squares component matching to produce false color representations of distribution of the drugs was used. This clearly showed a definitive separation between the drug layers of paracetamol and caffeine. Drug release tests in biorelevant bicarbonate media showed unique drug release profiles dependent on the macrostructure of the devices. In the case of the multilayer devices, release of both paracetamol and caffeine was simultaneous and independent of drug solubility. With the DuoCaplet design, it was possible to engineer either rapid drug release or delayed release by selecting the site of incorporation of the drug in the device; the lag-time for release from the internal compartment was dependent on the characteristics of the external layer. The study confirms the potential of 3D printing to fabricate multiple-drug containing devices with specialized design configurations and unique drug release characteristics, which would not otherwise be possible using conventional manufacturing methods.


Assuntos
Acetaminofen/química , Cafeína/química , Composição de Medicamentos/métodos , Impressão Tridimensional/instrumentação , Comprimidos/química , Liberação Controlada de Fármacos , Humanos , Polímeros/química , Tecnologia Farmacêutica
15.
Mol Pharm ; 11(12): 4327-38, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25317777

RESUMO

Following an array of optimization experiments, two series of electrospun polyvinylpyrrolidone (PVP) fibers were prepared. One set of fibers contained various loadings of indomethacin, known to form stable glasses, and the other griseofulvin (a poor glass former). Drug loadings of up to 33% w/w were achieved. Electron microscopy data showed the fibers largely to comprise smooth and uniform cylinders, with evidence for solvent droplets in some samples. In all cases, the drug was found to exist in the amorphous physical state in the fibers on the basis of X-ray diffraction and differential scanning calorimetry (DSC) measurements. Modulated temperature DSC showed that the relationship between a formulation's glass transition temperature (Tg) and the drug loading follows the Gordon-Taylor equation, but not the Fox equation. The results of Gordon-Taylor analysis indicated that the drug/polymer interactions were stronger with indomethacin. The interactions between drug and polymer were explored in more detail using molecular modeling simulations and again found to be stronger with indomethacin; the presence of significant intermolecular forces was further confirmed using IR spectroscopy. The amorphous form of both drugs was found to be stable after storage of the fibers for 8 months in a desiccator (relative humidity <25%). Finally, the functional performance of the fibers was studied; in all cases, the drug-loaded fibers released their drug cargo very rapidly, offering accelerated dissolution over the pure drug.


Assuntos
Portadores de Fármacos/química , Griseofulvina/química , Indometacina/química , Varredura Diferencial de Calorimetria , Temperatura
16.
Nutrition ; 121: 112353, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38402669

RESUMO

OBJECTIVE: The same microbial species isolated from blood simultaneously drawn from a central venous catheter hub and a peripheral vein (paired blood cultures) during parenteral nutrition may be assumed to represent the same strain. This case report provides an example of this assumption being incorrect along with a comparator example of it being correct. This has implications for interpretation of differential time to positivity and differential quantitative blood cultures during investigation of suspected intraluminal intravascular catheter or cannula bloodstream infection. CASE DESCRIPTION: Two patients ages ≥18 y prescribed parenteral nutrition each had positive paired blood cultures that had been taken for suspected catheter bloodstream infection because of temperature spikes ≥38°C. The paired Staphylococcus epidermidis isolates from the first patient and the paired Enterococcus faecium isolates from the second patient were each tested beyond routine clinical care to establish if they could be different strains. The central and peripheral isolates of Staphylococcus epidermidis from the first patient were different strains based on hospital-reported antibiograms, genomic DNA profiles, thermograms, and weaker growth and different sizes of colonies of the central strain compared with the peripheral strain. There were no such differences for the isolates of Enterococcus faecium from the second patient. RESULTS: The central and peripheral isolates of Staphylococcus epidermidis from the first patient were different strains based on hospital-reported antibiograms, genomic DNA profiles, thermograms, and weaker growth and different sizes of colonies of the central strain compared with the peripheral strain. There were no such differences for the isolates of Enterococcus faecium from the second patient. CONCLUSION: This case report indicates consideration should be given to reporting whether bacteria have been identified at either species or strain level if differential time to positivity or differential quantitative blood cultures are used to define catheter or cannula bloodstream infection.


Assuntos
Bacteriemia , Sepse , Humanos , Hemocultura , Bacteriemia/microbiologia , Sepse/complicações , Catéteres/efeitos adversos , DNA , Nutrição Parenteral/efeitos adversos
17.
Nutrition ; 119: 112319, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38194818

RESUMO

OBJECTIVES: Because bloodstream infection and venous catheter (or cannula) bloodstream infection are associated with high morbidity and cost, early identification and treatment are important. Isothermal microcalorimetry can detect microbial growth using thermal power (heat flow), essentially in real time. The aim of this study was to examine the potential of this technique in clinical practice. METHODS: Thermal power of wild-type bacteria (Escherichia coli, Staphylococcus epidermidis, Klebsiella pneumoniae, and Enterococcus faecium) isolated from blood cultures of adult inpatients receiving parenteral nutrition in routine clinical practice was measured at 37°C every 10s using a Thermometric 2277 instrument. Temporal patterns of heat flow were used to detect the presence of bacteria, differentiate between them, and test their antibiotic sensitivity. Within and between batch reproducibility (% coefficient of variation [%CV]) was also established. RESULTS: Isothermal microcalorimetry always correctly detected the absence or presence of wild-type bacteria. Thermograms differed distinctly between species. Key thermographic features, such as peak heights, timing of peak heights, and interval between peak heights, were highly reproducible within each species (within-batch %CV usually about ≤1%, although between-batch %CV was usually higher). The antibiotic sensitivities (tested only for S. epidermidis and K. pneumoniae) confirmed the results obtained from the hospital laboratory. CONCLUSIONS: Isothermal microcalorimetry is a promising and highly reproducible real-time measurement technique with potential application to the investigation, species identification, and targeted antibiotic treatment of bloodstream infection and venous catheter (or cannula) bloodstream infection.


Assuntos
Escherichia coli , Sepse , Adulto , Humanos , Reprodutibilidade dos Testes , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Catéteres
18.
Int J Pharm ; 652: 123741, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38181989

RESUMO

Artificial intelligence (AI) is a revolutionary technology that is finding wide application across numerous sectors. Large language models (LLMs) are an emerging subset technology of AI and have been developed to communicate using human languages. At their core, LLMs are trained with vast amounts of information extracted from the internet, including text and images. Their ability to create human-like, expert text in almost any subject means they are increasingly being used as an aid to presentation, particularly in scientific writing. However, we wondered whether LLMs could go further, generating original scientific research and preparing the results for publication. We taskedGPT-4, an LLM, to write an original pharmaceutics manuscript, on a topic that is itself novel. It was able to conceive a research hypothesis, define an experimental protocol, produce photo-realistic images of 3D printed tablets, generate believable analytical data from a range of instruments and write a convincing publication-ready manuscript with evidence of critical interpretation. The model achieved all this is less than 1 h. Moreover, the generated data were multi-modal in nature, including thermal analyses, vibrational spectroscopy and dissolution testing, demonstrating multi-disciplinary expertise in the LLM. One area in which the model failed, however, was in referencing to the literature. Since the generated experimental results appeared believable though, we suggest that LLMs could certainly play a role in scientific research but with human input, interpretation and data validation. We discuss the potential benefits and current bottlenecks for realising this ambition here.


Assuntos
Inteligência Artificial , Biofarmácia , Humanos , Vibração
19.
Adv Healthc Mater ; 13(3): e2301759, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37861058

RESUMO

Conductive materials have played a significant role in advancing society into the digital era. Such materials are able to harness the power of electricity and are used to control many aspects of daily life. Conductive polymers (CPs) are an emerging group of polymers that possess metal-like conductivity yet retain desirable polymeric features, such as processability, mechanical properties, and biodegradability. Upon receiving an electrical stimulus, CPs can be tailored to achieve a number of responses, such as harvesting energy and stimulating tissue growth. The recent FDA approval of a CP-based material for a medical device has invigorated their research in healthcare. In drug delivery, CPs can act as electrical switches, drug release is achieved at a flick of a switch, thereby providing unprecedented control over drug release. In this review, recent developments in CP as electroactive polymers for voltage-stimuli responsive drug delivery systems are evaluated. The review demonstrates the distinct drug release profiles achieved by electroactive formulations, and both the precision and ease of stimuli response. This level of dynamism promises to yield "smart medicines" and warrants further research. The review concludes by providing an outlook on electroactive formulations in drug delivery and highlighting their integral roles in healthcare IoT.


Assuntos
Sistemas de Liberação de Medicamentos , Polímeros , Liberação Controlada de Fármacos , Hidrogéis , Condutividade Elétrica
20.
Eur J Pharm Sci ; 200: 106845, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38971433

RESUMO

The gut microbiota is a complex ecosystem, home to hundreds of bacterial species and a vast repository of enzymes capable of metabolising a wide range of pharmaceuticals. Several drugs have been shown to affect negatively the composition and function of the gut microbial ecosystem. Janus Kinase (JAK) inhibitors and Sphingosine-1-phosphate (S1P) receptor modulators are drugs recently approved for inflammatory bowel disease through an immediate release formulation and would potentially benefit from colonic targeted delivery to enhance the local drug concentration at the diseased site. However, their impact on the human gut microbiota and susceptibility to bacterial metabolism remain unexplored. With the use of calorimetric, optical density measurements, and metagenomics next-generation sequencing, we show that JAK inhibitors (tofacitinib citrate, baricitinib, filgotinib) have a minor impact on the composition of the human gut microbiota, while ozanimod exerts a significant antimicrobial effect, leading to a prevalence of the Enterococcus genus and a markedly different metabolic landscape when compared to the untreated microbiota. Moreover, ozanimod, unlike the JAK inhibitors, is the only drug subject to enzymatic degradation by the human gut microbiota sourced from six healthy donors. Overall, given the crucial role of the gut microbiome in health, screening assays to investigate the interaction of drugs with the microbiota should be encouraged for the pharmaceutical industry as a standard in the drug discovery and development process.


Assuntos
Microbioma Gastrointestinal , Doenças Inflamatórias Intestinais , Inibidores de Janus Quinases , Moduladores do Receptor de Esfingosina 1 Fosfato , Humanos , Microbioma Gastrointestinal/efeitos dos fármacos , Inibidores de Janus Quinases/farmacologia , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/microbiologia , Doenças Inflamatórias Intestinais/metabolismo , Pirazóis/farmacologia , Colo/microbiologia , Colo/metabolismo , Colo/efeitos dos fármacos , Sulfonamidas/farmacologia , Sulfonamidas/administração & dosagem , Purinas , Azetidinas/farmacologia , Azetidinas/administração & dosagem , Compostos de Benzil/farmacologia , Compostos de Benzil/administração & dosagem , Piperidinas/farmacologia , Piperidinas/administração & dosagem , Pirimidinas/farmacologia , Pirimidinas/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Oxidiazóis/farmacologia , Oxidiazóis/administração & dosagem , Receptores de Esfingosina-1-Fosfato/metabolismo , Receptores de Esfingosina-1-Fosfato/antagonistas & inibidores , Pirróis/farmacologia , Pirróis/administração & dosagem , Indanos/farmacologia , Indanos/administração & dosagem , Piridinas , Triazóis
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