Enhancing the dissolution of phenylbutazone using Syloid® based mesoporous silicas for oral equine applications

Three mesoporous silica excipients (Syloid® silicas AL-1 FP, XDP 3050 and XDP 3150) were formulated with a model drug known for its poor aqueous solubility, namely phenylbutazone, in an attempt to enhance the extent and rate of drug dissolution. Although other forms of mesoporous silica have been investigated in previous studies, the effect of inclusion with these specific Syloid® silica based excipients and more interestingly, with phenylbutazone, is unknown. This work reports a significant enhancement for both the extent, and rate, of drug release for all three forms of Syloid® silica at a 1:1 drug:silica ratio over a period of 30 minutes. An explanation for this increase was determined to be conversion to the amorphous form and an enhanced drug loading ability within the pores. Differences between the release profiles of the three silicas was concluded to be a consequence of the physicochemical differences between the three forms. Overall, this study confirms that Syloid® silica based excipients can be used to enhance dissolution, and potentially therefore bioavailability, for compounds with poor aqueous solubility, such as phenylbutazone. In addition, it has been confirmed that drug release can be carefully tailored based on the choice of Syloid® silica and desired release profile

A study of clinico etiological profile of children with cerebral palsy in a tertiary care centre

The clinical spectrum of Cerebral palsy (CP) can differ in various places depending upon the knowledge of the people and resources for prevention, diagnosis and management. Although studied extensively in high-resource countries, adequate data related to CP from resource-constraint settings are lacking. The aim: The present study is a descriptive study done on clinical profiles, aetiology, and comorbidities. Materials and methods: Present study is a hospital-based descriptive study of 80 children with Cerebral Palsy from January 2020 to June 2021 (18 months) admitted to Niloufer Hospital for Child Health, cases chosen as per inclusion criteria guided by "The Definition and classification of cerebral palsy, April 2006 International consensus". Clinical history and clinical examination and necessary investigations using a systematically designed proforma Results: The most common types were spastic type (78.9 %) and hypotonic type (12.5 %). Spastic quadriparesis (55 %) was the most common among subtypes. Males were more affected than females, with more rural than urban distribution. 48.8 % belonged to the lower middle and 37.5 % to the upper lower class of socio-economic status. Consanguinity was observed in 33 %, and 3 % had a similar family history. A high incidence (65 %) was seen in firstborn children. Term gestation was commonest at 87 % and prematurity at 13 %. 91.3 % of the cases were institutional deliveries. For causes of cerebral palsy, 45 % required resuscitation at birth, 2.5 % had neonatal sepsis, 1.25 % had a cerebral malformation, 7.5 % had an intracranial bleed, 7.5 % had post-meaning encephalitic sequelae, 1.3 % had TORCH infection. Comorbidities Like mental retardation were seen in 90 %, seizure disorder in 87.5 %, visual problems in 24.8 %, hearing problems in 13.75 %, 56.25 % of cases were malnourished. Conclusions: Comorbidities are significantly observed in cases of cerebral palsy. Appropriate screening and management of comorbidities, especially vision, hearing, speech, seizures, and nutrition, improve the overall prognosis in cases of Cerebral palsy

Vat polymerization-based 3D printing of nanocomposites: A mini review

Vat polymerization, the earliest and most established 3D printing technology, offers abundant advantages of high-precision fabrication and rapid printing speed, among others. This technology is often applied to fabricated objects with complex and delicate structures, which are of specific interest in numerous fields. However, it suffers from poor mechanical properties of the resultant printed parts due to layer-by-layer manufacturing patterns and the absence of functionality, restricting the broader application of printed objects. Integrating nanomaterials with vat polymerization-based 3D printing endows the creation of products with enhanced properties and unprecedented functional adjunction with flexible designs. Giving a brief description of 3D printing technology, this review illustrates the principles and characteristics of vat polymerization technology. In this mini-review, we emphasize recent advances in nanocomposite fabricated using vat polymerization, predominantly focusing on creating nanocomposites with enhanced mechanical, thermal properties, and electrical conductivity. Finally, we summarize the article with the challenges being faced and future perspectives of nanocomposites fabricated from vat polymerization

Polymeric microcarriers for minimally-invasive cell delivery

Tissue engineering (TE) aims at restoring tissue defects by applying the three-dimensional (3D) biomimetic pre-formed scaffolds to restore, maintain, and enhance tissue growth. Broadly speaking, this approach has created a potential impact in anticipating organ-building, which could reduce the need for organ replacement therapy. However, the implantation of such cell-laden biomimetic constructs based on substantial open surgeries often results in severe inflammatory reactions at the incision site, leading to the generation of a harsh adverse environment where cell survival is low. To overcome such limitations, micro-sized injectable modularized units based on various biofabrication approaches as ideal delivery vehicles for cells and various growth factors have garnered compelling interest owing to their minimally-invasive nature, ease of packing cells, and improved cell retention efficacy. Several advancements have been made in fabricating various 3D biomimetic microscale carriers for cell delivery applications. In this review, we explicitly discuss the progress of the microscale cell carriers that potentially pushed the borders of TE, highlighting their design, ability to deliver cells and substantial tissue growth in situ and in vivo from different viewpoints of materials chemistry and biology. Finally, we summarize the perspectives highlighting current challenges and expanding opportunities of these innovative carriers

Investigation of Various Cross-Linking Methods for the Immobilization of Cytosine Arabinoside on Bacterial Magnetosomes

Bacterial magnetosomes (BMs) have emerged as potential drug delivery vehicles, possessing an iron oxide or iron sulfide core surrounded by a natural lipid membrane shell. In this study, we immobilized cytosine arabinoside (Ara-C) effectively on BMs by using various methods such as direct absorption (ABMs), and others include different cross-linkers such as genipin (GP) and glutaraldehyde (G). A well-dispersed Ara-C coupled bacterial magnetosomes resulted in significantly higher negative charge than that of naked BMs (−11.5±0.3 mV) confirming the drug loading. Out of all methods, direct absorption process led to the highest encapsulation efficiency and drug loading of 88.2±4.3% and 46.9±1.2%, respectively. These designs have shown the long-term drug release behavior without an initial burst release. Our results indicate that BMs-based nanoconjugates will potentially find widespread applications in pharmaceutical field

Metal Species-Encapsulated Mesoporous Silica Nanoparticles : Current Advancements and Latest Breakthroughs

Despite their advantageous morphological attributes and attractive physicochemical properties, mesoporous silica nanoparticles (MSNs) are merely supported as carriers or vectors for a reason. Incorporating various metal species in the confined nanospaces of MSNs (M‐MSNs) significantly enriches their mesoporous architecture and diverse functionalities, bringing exciting potentials to this burgeoning field of research. These incorporated guest species offer enormous benefits to the MSN hosts concerning the reduction of their eventual size and the enhancement of their performance and stability, among other benefits. Substantially, the guest species act through contributing to reduced aggregation, augmented durability, ease of long‐term storage, and reduced toxicity, attributes that are of particular interest in diverse fields of biomedicine. In this review, the first aim is to discuss the current advancements and latest breakthroughs in the fabrication of M‐MSNs, emphasizing the pros and cons, the confinement of various metal species in the nanospaces of MSNs, and various factors influencing the encapsulation of metal species in MSNs. Further, an emphasis on potential applications of M‐MSNs in various fields, including in adsorption, catalysis, photoluminescence, and biomedicine, among others, along with a set of examples is provided. Finally, the advances in M‐MSNs with perspectives are summarized.Peer reviewe

In vivo assessment of a novel biodegradable ureteral stent

Purpose: To perform an in vivo assessment of a newly developed biodegradable ureteral stent (BUS) produced with natural-based polymers. Methods: The BUS is based on a patented technology combining the injection process with the use of supercritical fluid technology. The study was conducted at ICVS-University of Minho (Braga, Portugal) and a total of ten domestic pigs were used. In seven animals, the experimental BUS stent was inserted, whereas in the remaining a commercially available stent was used (6-Fr Biosoft(®) duo stents, Porges Coloplast, Denmark). Post-stenting intravenous pyelogram was used to evaluate the degree of hydronephrosis. The in vivo stent degradation was measured as a function of the weight loss. Moreover, the tensile properties of the BUS were tested during in vivo degradation. After maximum 10 days, animals were killed and necropsy was performed. Tissues were compared between the stented groups as well as between the non-stented contralateral ureters and stented ureters in each group. Biocompatibility was assessed by histopathological grading. Results: In all cases, the BUS was only visible during the first 24 h on X-ray, and in all cases, the BUS was completely degraded in urine after 10 days, as confirmed on necropsy. During the degradation process, the mechanical properties of the BUS decreased, while the commercial ureteral stents remained constant. At all time-points after stent insertion, the level of hydronephrosis was minimal. Overall, animals stented with BUS had an average grade of hydronephrosis which was lower compared to the controls. The BUS showed better pathological conditions, and hence better biocompatibility when compared with commercial stents. Conclusions: Notwithstanding the limitations of the present study, the in vivo testing of our novel natural origin polymer-based BUS suggests this device to feature homogeneous degradation, good urine drainage, and high biocompatibility. Next steps will be to increase its stability and to improve the radiopacity without compromising its degradation. Ultimately, clinical studies will be required to determine the safety and feasibility of its use in humans.FCT -Fuel Cell Technologies Program(POCI-01-0145-FEDER-007038)info:eu-repo/semantics/publishedVersio

Metal-catalyzed 1,3-dipolar cycloaddition reactions of nitrile oxides

In the present review advances in the metal-catalyzed 1,3-dipolar cycloaddition reactions of nitrile oxides, mainly in the last decade, will be presented and discussed. An overview on the structure, preparation, dimerization and related reactions as well as the relevant aspects in the cycloaddition chemistry of nitrile oxides (including mechanistic aspects) have also been considered

A hemilabile and cooperative N-donor functionalized 1,2,3-triazol- 5-ylidene ligand for selective and base-free rhodium(I) catalyzed alkyne hydrothiolation reactions

A series of novel cationic and neutral Rh-complexes with an N-donor functionalized 1,2,3-triazol-5-ylidene (TRZ) ligand (where pendant N-donor is NHBoc, NH2 or NMe2 respectively) is described. Their catalytic activity was evaluated towards the hydrothiolation of alkynes. Among the catalysts, a neutral dicarbonyl complex featuring the tethered-NBoc amido-TRZ ligand proved very selective for alkyne hydrothiolation with an aryl thiol. Remarkably, the reaction could be carried out in the absence of pyridine or base additive. In addition, during the reaction course, no evidence for oxidative addition of the thiol S-H was observed, strongly suggesting a reaction pathway whereby a bifunctional ligand is involved. Experimental and theoretical mechanistic investigations suggest a ligand-assisted deprotonation of substrate thiol, hemilabile dissociation of amine from metal and thiolate coordination, which is indicative of a different reaction mechanism to those previously reported for related alkyne hydrothiolation reaction.G. G.-B. thanks the MINECO for a postdoctoral grant (FPDI- 2013-16525) and Generalitat Valenciana (GV/2015/097) for financial support. E.P and I.F. gratefully acknowledge financial support from the Spanish MINECO-FEDER (CTQ2014-51999-P to E.P. and CTQ2013-44303-P and CTQ2014-51912-REDC to I.F.), UJI (P11B2014-02 to E.P.). D.I.B and I.S. gratefully acknowledge the National Research Foundation, South Africa (NRF 87890, 103698 and 92521), and Sasol Technology R&D Pty. Ltd., South Africa for financial support.http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1521-37652018-01-31hb2017Chemistr