IntroductionChronic vascular exposure to elevated levels of lipoprotein-amyloid-β (Aβ) contributes to blood–brain barrier (BBB) disruption and the pathogenesis of Alzheimer’s disease (AD). Therapeutic agents such as probucol have been shown to reduce circulating lipoprotein-Aβ levels and mitigate neurovascular dysfunction and cognitive decline. Type 2 diabetes (T2D) impairs BBB integrity and is characterised by dyslipidaemia and metabolic disturbances that may influence the peripheral metabolism of lipoprotein-Aβ. However, the effects of diabetes on lipoprotein-Aβ homeostasis and neurovascular integrity remain poorly understood. This study investigated whether diabetes impairs lipoprotein and Aβ metabolism and whether treatment with HA1, a probucol analogue with improved bioavailability, or APOC3 siRNA can modify these metabolic changes and improve neurovascular and behavioural outcomes.MethodsNon-diabetic db/+ mice, untreated diabetic db/db mice, and diabetic db/db mice treated with HA1 or APOC3 siRNA were used to determine how diabetes and therapeutic modulation of lipoprotein metabolism affect circulating Aβ, neurovascular integrity, and behavioural outcomes. Total plasma Aβ and ApoB levels were measured by ELISA. Intestinal Aβ and ApoB, neurovascular integrity, neuroinflammation, and oxidative stress were assessed by immunofluorescence. Anxiety-like behaviour and short- and long-term memory were evaluated using the open field, novel object recognition, and passive avoidance testsResultsDiabetic db/db mice exhibited increased intestinal Aβ and ApoB immunoreactivity and elevated total plasma Aβ42, Aβ oligomer and ApoB, accompanied by heightened BBB permeability and anxiety-like phenotype. HA1 reduced intestinal Aβ and lowered plasma Aβ42 and Aβ oligomer, prevented IgG extravasation, and improved anxiety. APOC3 siRNA lowered plasma ApoB and plasma Aβ42 and attenuated neuroinflammation, but did not reduce IgG extravasation.ConclusionDysregulated lipoprotein and Aβ metabolism are associated with neurovascular dysfunction and anxiety-like behaviour in diabetes. HA1 shows therapeutic potential by modulating Aβ metabolism and improving neurovascular and behavioural outcomes.

Background: Caffeine (CAF), whether extracted from plants or synthesised as a chemical compound, is considered the safest among other xanthine alkaloids. Novel nano-cream formulations have been successfully developed and evaluated to increase the potential of caffeine as a skin cosmeceutical, targeting the minimisation of cellulite appearance. Methods: Nano-cream formulations were prepared through a process of hot-temperature emulsification, in a variety of homogeniser combinations. Results: When chemical penetration enhancers (CPEs) (lanolin, transcutol, and propylene glycol), either alone or in combination, were incorporated into the nano-cream formulations, the permeation of CAF through skin increased. All nano-cream formulations achieved sustained delivery of CAF into and through the skin over 8 h (IVPT). Quantification of CAF from skin tissues was achieved using high-performance liquid chromatography (HPLC). The nano-cream formulation containing lanolin (LAN) showed the highest CAF permeation (8.829 ± 1.472 µg/cm2/h) through the skin compared to CAF in an aqueous solution (2.533 ± 0.480 µg/cm2/h) and a commercial CAF cellulite product with the same CAF concentration (2.827 ± 0.555 µg/cm2/h). Therefore, 2% CAF nano-cream formulation containing LAN was chosen for clinical testing. A double-blind, randomised, placebo-controlled paired trial was conducted, in which each volunteer applied active and placebo creams to the upper thighs twice daily for 12 weeks. The effect of the cream on skin appearance was monitored over 12 weeks. The primary outcome measures were reduced cellulite scores from 3.96 (95% CI: 3.16–4.76) to 2.50 (95% CI: 1.70–3.30) (active) compared with placebo from 3.88 (95% CI: 3.08–4.67) to 2.83 (95% CI: 2.03–3.63). The effect sizes (E.S.) indicated a moderate effect for the active CAF nano-cream formulation (E.S. = 0.475), while the placebo (E.S. = 0.286) had a small effect. Conclusion: We concluded that our optimised 2% CAF nano-cream formulation containing LAN offered an effective formulation strategy for enhancing skin penetration in the IVPT study. The LAN nano-cream formulation demonstrated efficacy and tolerability, both objectively and subjectively, in a human clinical trial.

Purpose:Ketamine has been previously administered as an anesthetic but recently gained importance as an analgesic in pediatric oncology. Despite its efficacy, continuous intravenous administration to children with cancer is interrupted when other essential drugs require infusion. This occurs because its compatibility with many drugs and lipid emulsions is unknown, causing inadequate pain management and patient discomfort. This study has assessed the physicochemical compatibility and stability of ketamine with selected drugs, based on usage frequency data, and lipid emulsion formulations administered to pediatric cancer patients at tertiary hospitals. Methods:Physicochemical compatibility of ketamine involved admixture with selected concentrations of drugs, for physical incompatibility. Admixtures of ketamine with lipid emulsions and the other drugs included determining ketamine's chemical concentration using high performance liquid chromatography (HPLC). Particle size analysis investigated lipid stability. Results:The HPLC assay was linear over a range of concentrations (0.05 mg/mL - 0.5 mg/mL), validated under forced degradation conditions causing no interferences and an intra- and inter-day precision less than 2%. Ketamine was highly stable with all drugs and lipid emulsions tested, retaining >90% of its concentration for all systems investigated for two hours. No additional physical incompatibility occurred., but amoxicillin incompatibility was confirmed. Lipid emulsion stability was maintained, with no system exceeding particle size limits. Conclusions:Ketamine is safe to co-administer with AmBisome®, cyclizine, hydromorphone, Intralipid®, magnesium sulfate, metoclopramide, micafungin, potassium dihydrogen phosphate, sodium dihydrogen phosphate and vancomycin. Our findings are significant for improving pain management in vulnerable patients simultaneously administered the tested drugs with ketamine.

Hyperuricemia is characterised by high blood levels of uric acid, and it can degenerate into gout when monosodium urate crystals precipitate in joints and other tissues. Uric acid is produced during the catabolism of xanthine by the enzyme xanthine oxidase (XO), which is the primary therapeutic target in gout treatment. Current XO inhibitors approved to treat gout, such as allopurinol and febuxostat, suffer from serious adverse effects, creating the need for new drug molecules. Three libraries comprising 75 purine analogues were designed using a 1,2,4-triazolo[1,5-a]pyrimidine scaffold, synthesised and tested in vitro as potential XO inhibitors. The screening identified that 23 compounds exhibited better inhibitory activity than allopurinol, with 2-(4-isopropoxyphenyl)-7-oxo-4,7-dihydro-1,2,4-triazolo[1,5-a]pyrimidine-6-carboxylic acid being 23 times more potent. Enzyme kinetics studies and molecular docking simulations were performed on the most active compounds to identify the mechanism of action and intermolecular interactions between the active site of XO and the inhibitors. The most potent compounds exhibited a mix-type inhibition mechanism and were predicted to interact with the same amino acid residues as allopurinol. These novel purine analogues are promising hits for further new lead development among purine-like drug XO inhibitors with therapeutic potential in the treatment of hyperuricemia and associated diseases.

Purpose: Amoxicillin/clavulanate antibiotic combination is suitable for treating a range of infections, including some suited for Outpatient Parenteral Antimicrobial Therapy (OPAT). The aim of the study was to evaluate shelf-life values of amoxicillin at clinical concentrations in the presence of clavulanate for use in OPAT. Methods: A stability-indicating HPLC assay was developed and validated. Kinetic studies were performed at 1 mg/mL and 15 mg/mL amoxicillin at 40-60 degrees C. Studies in elastomeric infusers included the pH lowered from 8.73 to 6.52 for 1 mg/mL; 8.85 to 7.69 for 7.5 mg/mL and 8.68 to 8.40 for 15 mg/mL amoxicillin plus clavulanate and stored at 2.9 degrees C. Results: Amoxicillin and clavulanate eluted at 5.2 and 3.0 minutes, respectively, with linear concentration relationships. Forced degradation retained base-line separation of each component in the presence of degradation products. Amoxicillin 1 mg/mL had a shelf-life of 4.85 hours at pH 6.53 and 40 degrees C which on extrapolation to 25 degrees C was 22.8 h. Clavulanate was 1.38 h at 40 degrees C and 4.0 h at 25 degrees C. Amoxicillin 15 mg/mL at pH 8.34 gave a shelf-life of 0.11 h at 40 degrees C and clavulanate 0.41 h. In elastomeric infusers, amoxicillin 1 mg/mL, with lowering pH from 8.73 to 6.52, improved the shelf-life at 2.9 degrees C from 72 to >263.8 h and similarly for clavulanate. At 7.5 mg/mL amoxicillin, lowering pH from 8.85 to 7.69 improved the shelf-life from 4.2 to 51.8 h and clavulanate from 4.2 to 48.0 h. At 15 mg/mL amoxicillin, the shelf-life values at pH 8.68 or 8.40 were 3.8 h and 1.6 h and similarly for clavulanate. Conclusion: Amoxicillin and clavulanate showed adequate stability at 2.9 degrees C for OPAT storage at 1 mg/mL and possibly 7.5 mg/mL, but not 15 mg/mL. Low shelf-life values at 25 degrees C also limit administration times.

Abstract Background and aims Chronically elevated levels of circulating lipoprotein-amyloid-beta (Abeta) are implicated in the disruption of the blood-brain barrier and the initiation of a neurodegenerative cascade leading to Alzheimers disease (AD). Type 2 diabetes is associated with BBB dysfunction, dyslipidaemia, and an increased risk of AD. However, alterations in triglyceride-rich lipoproteins (TRL)-Abeta homeostasis and its downstream effects on the BBB in a diabetes context remain explored. This study aimed to 1) investigate, in a preclinical model of diabetes, the hypothesis that diabetes-induced impairments in TRL-Abeta metabolism might compromise BBB integrity and exacerbate cognitive function and behavioural changes, and 2) assess the efficacy of interventions that improve TRL catabolism, including probucol, HA1, and ApoC3 siRNA, to prevent disease progression by lowering circulating TRL-Abeta levels. Methods Five-week-old db/db mice underwent a 9- or 23-weeks dietary interventions with probucol, a probucol prodrug HA1, or a standard diet with four-weekly injections of ApoC3 siRNA. Db/+ mice served as negative controls for each treatment duration. Blood levels of Abeta and ApoB were measured using ELISA. Immunofluorescence imaging was used to quantify enterocytic levels of Abeta and ApoB, and assess changes in neurovascular integrity (IgG, PDGFRbeta, ZO1, occludin), neuroinflammation (GFAP, Iba1), and cerebral oxidative stress (8OHdG). Results Our results indicate that diabetes increased the abundance of plasma amyloid, specifically Abeta42, which correlated with enterocytic abundance, suggesting exaggerated postprandial excretion. Disrupted plasma amyloid homeostasis was associated with BBB breakdown, including diminished barrier function, and the loss of pericytes and astrocytes. Provision of the probucol analogue, HA1, normalised plasma and enterocytic amyloidemia concomitant with the preservation of the neurovascular junction. Treatment with ApoC3 siRNA attenuated plasma Abeta42 and modestly reduced neurovascular inflammation. Conclusion The findings further support the hypothesis that aberrant peripheral metabolism of lipoprotein-Abeta is associated with microvascular corruption and the development of anxiety-like behaviour. HA1 is more effective than probucol or ApoC3 siRNA in positively modulating lipoprotein-amyloid homeostasis in db/db mice and maintaining central capillary integrity. ### Competing Interest Statement The authors have declared no competing interest.

Neurodegenerative disorders present complex pathologies characterized by various interconnected factors, including the aggregation of misfolded proteins, oxidative stress, neuroinflammation and compromised blood–brain barrier (BBB) integrity. Addressing such multifaceted pathways necessitates the development of multi-target therapeutic strategies. Emerging research indicates that probucol, a historic lipid-lowering medication, offers substantial potential in the realm of neurodegenerative disease prevention and treatment. Preclinical investigations have unveiled multifaceted cellular effects of probucol, showcasing its remarkable antioxidative and anti-inflammatory properties, its ability to fortify the BBB and its direct influence on neural preservation and adaptability. These diverse effects collectively translate into enhancements in both motor and cognitive functions. This review provides a comprehensive overview of recent findings highlighting the efficacy of probucol and probucol-related compounds in the context of various neurodegenerative conditions, including Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, and cognitive impairment associated with diabetes.

Pigment epithelium-derived factor (PEDF) is a secreted glycoprotein that belongs to the serine protease inhibitor (serpin) family. An increase in PEDF activity has been shown to be a potent inhibitor of tumour progression and proliferation, suggesting a possible therapeutic target. There is still a great deal to learn about how PEDF controls metabolic pathways in breast cancer and its metastatic form. Given this, the primary purpose of this study was to use a metabolomics approach to gain a better understanding of the mechanisms driving the reprogramming of metabolic events involved in breast cancer pertaining to PEDF under various glycaemic loads. We employed gas chromatography–quadrupole mass spectrometry (GC-Q-MS) to investigate metabolic changes in the triple-negative breast cancer (TNBC) cell line MDA-MB-231 treated with PEDF under glycaemic loading. Multivariate and univariate analyses were carried out as indicative tools via MetaboAnalyst (V.5.0) and R packages to identify the significantly altered metabolites in the MDA-MB-231 cell line after PEDF exposure under glycaemic loading. A total of 61 metabolites were found, of which nine were selected to be distinctively expressed in MDA-MB-231 cells under glycaemic conditions and exhibited differential responses to PEDF (p < 0.05, VIP > 1). Abnormalities in amino acid metabolism pathways were observed. In particular, glutamic acid, glutamine, and phenylalanine showed different levels of expression across different treatment groups. The lactate and glucose-6-phosphate production significantly increased in high-glucose vs. normal conditions while it decreased when the cells were exposed to PEDF, confirming the positive influence on the Warburg effect. The TCA cycle intermediates, including malate and citric acid, showed different patterns of expression. This is an important finding in understanding the link of PEDF with metabolic perturbation in TNBC cells in response to glycaemic conditions. Our findings suggest that PEDF significantly influenced the Warburg effect (as evidenced by the significantly lower levels of lactate), one of the well-known metabolic reprogramming pathways in cancer cells that may be responsive to metabolic-targeted therapeutic strategies. Moreover, our results demonstrated that GC-MS-based metabolomics is an effective tool for identifying metabolic changes in breast cancer cells after glycaemic stress or in response to PEDF treatment.

A novel gliclazide-loaded elastomeric carbohydrate pharmaceutical vehicle was successfully developed. This new siliconized alginate platform showed pseudoplastic rheology with a zeta potential ranging from (−43.8 mV to −75.5 mV). A Buchi-B390 encapsulator was employed to formulate different types of silicone-grafted alginate microcapsules loaded with gliclazide relying on the vibrational ionic gelation technology. The use of tetraethyl orthosilicate (TEOS) to crosslink the silicone elastomer (hydroxy terminated polydimethylsiloxane) of this new platform had improved the gliclazide encapsulation (>92.13% ± 0.76) of the free-flowing composite microcapsules, which showed good mechanical durability (up to 12 h in PBS pH 6.8) and promising results to sustain the drug release.

Aim: Examine bile acids effects in Type 2 diabetes. Background: In recent studies, the bile acid ursodeoxycholic acid (UDCA) has shown potent anti-inflammatory effects in obese patients while in type 2 diabetics (T2D) levels of the pro-inflammatory bile acid lithocholic acid were increased, and levels of the anti-inflammatory bile acid chenodeoxycholic acid were decreased, in plasma. Objective: Hence, this study aimed to examine applications of novel UDCA microparticles in diabetes. Methods: Diabetic balb/c adult mice were divided into three equal groups and gavaged daily with either empty microcapsules, free UDCA, or microencapsulated UDCA over two weeks. Their blood, tissues, urine, and faeces were collected for blood glucose, inflammation, and bile acid analyses. UDCA resulted in modulatory effects on bile acids profile without antidiabetic effects suggesting that bile acid modulation was not directly linked to diabetes treatment. Results: UDCA resulted in modulatory effects on bile acids profile without antidiabetic effects suggesting that bile acid modulation was not directly linked to diabetes treatment. Conclusion: Bile acids modulated the bile profile without affecting blood glucose levels.

Astaxanthin (ASX) is a potent lipophilic antioxidant derived from the natural pigment that gives marine animals their distinctive red-orange colour and confers protection from ultraviolet radiation. Self nano-emulsifying drug delivery systems (SNEDDS) have been successfully developed and evaluated to increase the skin penetration of ASX and target its antioxidant and anti-inflammatory potential to the epidermis and dermis. SNEDDS were prepared using a low-temperature spontaneous emulsification method, and their physical characteristics, stability, antioxidant activity, and skin penetration were characterized. Terpenes (D-limonene, geraniol, and farnesol) were included in the SNEDDS formulations to evaluate their potential skin penetration enhancement. An HPLC assay was developed that allowed ASX recovery from skin tissues and quantification. All SNEDDS formulations had droplets in the 20 nm range, with low polydispersity. ASX stability over 28 days storage in light and dark conditions was improved and antioxidant activity was high. SNEDDS-L1 (no terpene) gave significantly increased ASX penetration to the stratum corneum (SC) and the epidermis-dermis-follicle region (E + D + F) compared to an ASX in oil solution and a commercial ASX facial serum product. The SNEDDS-containing D-limonene gave the highest ASX permeation enhancement, with 3.34- and 3.79-fold the amount in the SC and E + D + F, respectively, compared to a similar applied dose of ASX in oil. We concluded that SNEDDS provide an effective formulation strategy for enhanced skin penetration of a highly lipophilic molecule, and when applied to ASX, have the potential to provide topical formulations for UV protection, anti-aging, and inflammatory conditions of the skin.

Abstract Benzathine penicillin G (BPG) is used as first‐line treatment for most forms of syphilis and as secondary prophylaxis against rheumatic heart disease (RHD). Perceptions that poor quality of BPG is linked to reported adverse effects and therapeutic failure may impact syphilis and RHD control programs. Clinical networks and web‐based advertising were used to obtain vials of BPG from a wide range of countries. The quality of BPG was assessed using a high performance liquid chromatography assay capable of detecting relevant impurities and degradation products. Tests for water content, presence of heavy metals and physical characteristics of BPG, including particle size analysis and optical microscopy, also were conducted. Thirty‐five batches of BPG were sourced from 16 countries across 4 WHO regions. All batches passed the US Pharmacopeia requirements for BPG injection (content), with no evidence of breakdown products or other detected contaminants. Water content and heavy metal analysis (n = 11) indicated adherence to regulatory standards and Good Manufacturing Practice. Particle size analysis (n = 20) found two batches with aggregated particles (>400 µm) that were dispersed following sonication. Current batches of BPG were of satisfactory pharmaceutical quality but aggregated particles were found in a modest proportion of samples. Future studies should focus on the physical characteristics of BPG which may contribute to variations in plasma penicillin concentrations an observed needle blockages in clinical practice. Pharmacopeial monographs could be revised to include standards on particle size and crystal morphology of BPG.

Our group has previously reported several indolecarboxamides exhibiting potent antitubercular activity. Herein, we rationally designed several arylcarboxamides based on our previously reported homology model and the recently published crystal structure of the mycobacterial membrane protein large 3 (MmpL3). Many analogues showed considerable anti-TB activity against drug-sensitive (DS) Mycobacterium tuberculosis (M. tb) strain. Naphthamide derivatives 13c and 13d were the most active compounds in our study (MIC: 6.55, 7.11 μM, respectively), showing comparable potency to the first line anti-tuberculosis (anti-TB) drug ethambutol (MIC: 4.89 μM). In addition to the naphthamide derivatives, we also identified the quinolone-2-carboxamides and 4-arylthiazole-2-carboxamides as potential MmpL3 inhibitors in which compounds 8i and 18b had MIC values of 9.97 and 9.82 μM, respectively. All four compounds retained their high activity against multidrug-resistant (MDR) and extensively drug-resistant (XDR) M. tb strains. It is worth noting that the two most active compounds 13c and 13d also exhibited the highest selective activity towards DS, MDR and XDR M. tb strains over mammalian cells [IC50 (Vero cells) ≥ 227 μM], indicating their potential lack of cytotoxicity. The four compounds were docked into the MmpL3 active site and were studied for their drug-likeness using Lipinski's rule of five.

BACKGROUND:Recent studies have suggested that hyperglycaemia influences the bile acid profile and concentrations of secondary bile acids in the gut.INTRODUCTION:This study aimed to measure changes in the bile acid profile in the gut, tissues, and faeces in type 1 Diabetes (T1D) and Type 2 Diabetes (T2D).METHODS:T1D and T2D were established in a mouse model. Twenty-one seven-weeks old balb/c mice were randomly divided into three equal groups, healthy, T1D and T2D. Blood, tissue, urine and faeces samples were collected for bile acid measurements.RESULTS:Compared with healthy mice, T1D and T2D mice showed lower levels of the primary bile acid, chenodeoxycholic acid, in the plasma, intestine, and brain, and higher levels of the secondary bile acid, lithocholic acid, in the plasma and pancreas. Levels of the bile acid ursodeoxycholic acid were undetected in healthy mice but were found to be elevated in T1D and T2D mice.CONCLUSION:Bile acid profiles in other organs were variably influenced by T1D and T2D development, which suggests similarity in effects of T1D and T2D on the bile acid profile, but these effects were not always consistent among all organs, possibly since feedback mechanisms controlling enterohepatic recirculation and bile acid profiles and biotransformation are different in T1D and T2D.

Hepatorenal syndrome (HRS) is a fatal complication of renal dysfunction associated with ascites, liver failure and advanced cirrhosis. Although the best option for long-term survival is liver transplantation, in the critical acute phase, vasoconstrictors are considered first-line supportive agents. Terlipressin is the most widely used vasoconstrictor globally but owing to its short elimination half-life, it is usually administered six hourly by slow intravenous bolus injection. This requires patients to remain in hospital, increasing hospital bed costs and affecting their quality of life. An alternative option for administration of terlipressin is as a continuous infusion using an elastomeric infusor device in the patient’s home. However, stability data on terlipressin in elastomeric infusor devices is lacking. This research aimed to evaluate the stability of terlipressin reconstituted in infusor devices for up to 7 days at 2–8 °C and subsequently at 22.5 °C for 24 h, to mimic home storage and administration temperatures. We report that terlipressin was physically and chemically stable under these conditions; all reconstituted infusor concentrations retained above 90% of the original concentration over the test conditions. No colour change or precipitation in the solutions were evident.

Ursodeoxycholic acid (UDCA) is a secondary hydrophilic bile acid, metabolised in the gut, by microbiota. UDCA is currently prescribed for primary biliary cirrhosis, and of recently has shown β-cell protective effects, which suggests potential antidiabetic effects. Thus, this study aimed to design targeted-delivery microcapsules for oral uptake of UDCA and test its effects in type 1 diabetes (T1D). UDCA microcapsules were produced using alginate-NM30 matrix. Three equal groups of mice (6–7 mice per group) were gavaged daily UDCA powder, empty microcapsules and UDCA microcapsules for 7 days, then T1D was induced by alloxan injection and treatments continued until mice had to be euthanised due to weight loss > 10% or severe symptoms develop. Plasma, tissues, and faeces were collected and analysed for bile acids’ concentrations. UDCA microcapsules brought about reduction in elevated blood glucose, reduced inflammation and altered concentrations of the primary bile acid chenodeoxycholic acid and the secondary bile acid lithocholic acid, without affecting survival rate of mice. The findings suggest that UDCA exerted direct protective effects on pancreatic β-cells and this is likely to be associated with alterations of concentrations of primary and secondary bile acids in plasma and tissues. Three equal groups of mice were gavaged daily UDCA (ursodeoxycholic acid) powder, empty microcapsules and UDCA microcapsules for 7 days, then T1D was induced and treatments continued until mice had to be euthanised. UDCA microcapsules brought about reduction in elevated blood glucose, reduced inflammation and altered concentrations of the primary bile acid chenodeoxycholic acid and the secondary bile acid lithocholic acid, without affecting survival rate of mice. The findings suggest that UDCA exerted direct protective effects on pancreatic β-cells and this is likely to be associated with alterations of concentrations of primary and secondary bile acids in plasma and tissues.

3-Amino-substituted 5-aminopyrazoles were found to be suitable substrates for the synthesis of new 4-aminopyrazolo[1,5-a][1,3,5]triazines (5-aza-9-deaza-adenines) when used in the one-pot, three-component reaction with cyanamide and triethyl orthoformate under microwave irradiation. The reaction proceeded selectively and its scope was demonstrated by the preparation of a library of 4-aminopyrazolo[1,5-a][1,3,5]triazines. Some structural aspects of the prepared compounds were investigated using dynamic NMR spectroscopy and X-ray crystallography. The operational simplicity, short reaction time, and good reproducibility are attractive features of the developed robust and practical approach for the synthesis of 7-amino-substituted 4-aminopyrazolo[1,5-a][1,3,5]triazines.

It was found that 3-amino-substituted 5-aminopyrazoles could be effectively prepared via hydrolytic decarboxylation of the corresponding 3,5-diaminopyrazole-4-carboxylates under microwave irradiation. The reactions required short time (4 min) and were successfully reproduced in a larger scale and under conventional heating mimicking the microwave heating pattern. X-ray crystallography identified two different types of tautomers in crystals of related 5-aminopyrazoles with p-toluidyl and p-anisidyl moieties at the position 3, respectively. (C) 2019 Elsevier Ltd. All rights reserved.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

Therapeutic proteins are labile macromolecules that are prone to degradation during production, freeze-drying and storage. Recent studies showed that nanoparticles can enhance the stability and oral bioavailability of encapsulated proteins. Several conventional approaches (enzyme inhibitors, mucoadhesive polymers) and novel strategies (surface modification, ligand conjugation, flash nano-complexation, stimuli-responsive drug delivery systems) have been employed to improve the physiochemical properties of nanoparticles such as size, zeta potential, morphology, polydispersity index, drug release kinetics and cell-targeting capacity. However, clinical translation of protein-based nanoparticle is limited due to poor experimental design, protocol non-compliance and instrumentation set-up that do not reflect the physiological conditions, resulting in difficulties in mass production of nanoparticles and waste in research funding. In order to address the above concerns, we conducted a comprehensive review to examine the experimental designs and conditions for physical characterization of protein-based nanoparticles. Reliable and robust characterization is essential to verify the cellular interactions and therapeutic potential of protein-based nanoparticles. Importantly, there are a number of crucial factors, which include sample treatment, analytical method, dispersants, sampling grid, staining, quantification parameters, temperature, drug concentration and research materials, should be taken into careful consideration. Variations in research protocol and unreasonable conditions that are used in optimization of pharmaceutical formulations can have great impact in result interpretation. Last but not least, we reviewed all novel instrumentations and assays that are available to examine mucus diffusion capacity, stability and bioactivity of protein-based nanoparticles. These include circular dichroism, fourier transform infrared spectroscopy, X-ray diffractogram, UV spectroscopy, differential scanning calorimetry, fluorescence spectrum, Förster resonance energy transfer, NMR spectroscopy, Raman spectroscopy, cellular assays and animal models.