Formulation of hesperidin‐loaded in situ gel for ocular drug delivery: a comprehensive study

BACKGROUND Allergic conjunctivitis is one of the most common eye disorders. Different drugs are used for its treatment. Hesperidin is an active substance isolated from Citrus sinensis L. (Rutaceae) fruit peels, with known anti‐inflammatory activity but low solubility. It was complexed with cyclodextrin and encapsulated in situ gel to extend its duration in the eye. RESULTS The optimized formulation comprised 1% hesperidin, 1.5% hydroxyethyl cellulose, and 16% poloxamer 407. The viscosity at 25 °C was 492 ± 82 cP, and at 35 °C it was 8875 ± 248 cP, the pH was 7.01 ± 0.03, gelation temperature was 34 ± 1.3 °C, and gelation time was 33 ± 1.2 s. There was a 66% in vitro release in the initial 2 h, with a burst effect. A lipoxygenase (LOX) inhibition test determined that hesperidin was active at high doses on leukotyrens seen in the body in allergic diseases. In cell‐culture studies, the hesperidin cyclodextrin complex loaded in situ gel, BRN9‐CD (poloxamer 16%, hydroxy ethyl cellulose (HEC) 1.5%), enhanced cell viability in comparison with the hesperidin solution. It was determined that BRN9‐CD did not cause any irritation in the ocular tissues in the Draize test. CONCLUSION The findings of this study demonstrate the potential of the in situ gel formulation of hesperidin in terms of ease of application and residence time on the ocular surface. Due to its notable LOX inhibition activity and positive outcomes in the in vivo Draize test, it appears promising for incorporation into pharmaceutical formulations. © 2024 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Combining Step‐Growth and Chain‐Growth Polymerizations in One Pot: Light‐Induced Fabrication of Conductive Nanoporous PEDOT‐PCL Scaffold

A novel method based on light‐induced fabrication of a poly (3,4‐ethylenedioxythiophene)‐polycaprolactone (PEDOT‐PCL) scaffold using phenacyl bromide (PAB) as a single‐component photoinitiator is presented. HBr released from the step‐growth polymerization of EDOT is utilized as an in situ catalyst for the chain‐growth polymerization of ε‐caprolactone. Detailed investigations disclose the formation of a self‐assembled nanoporous electroconductive scaffold (1.2 mS cm −1 ). Fluorescence emission spectra of the fabricated scaffold exhibit a mixed solvatochromic behavior, indicating specific interactions between the self‐assembled scaffold and solvents with varying polarities, as evidenced by transmission electron microscopy (TEM). Moreover, the same light‐induced technique can also be applied for bulk photopolymerization showcasing the versatility and wide‐ranging scope of the originated method. In brief, this study introduces a novel approach for light‐induced polymerization reactions that is merging step‐growth and chain‐growth mechanisms. This innovative approach is promising to facilitate in situ polymerization of monomers possessing diverse functionalities.

Use of the pedicle of previously harvested pectoral myocutaneous flap as a recipient for free flaps in head and neck reconstruction

The pectoral myocutaneous flap (PMF) is a workhorse regional reconstructive option for head and neck defects. It is commonly used for primary reconstructions due to its advantages or as a life‐boat flap in the salvage of failed reconstructions of free flaps. However, it also has intrinsic drawbacks, such as perfusion problems and partial or complete flap loss. Although there are many studies about the advantages and use of PMF in the literature, the number of studies about salvage of this workhorse flap is inadequate. We aimed to present the use of the pedicle of previously performed PMF as a recipient for free flaps in head and neck reconstruction. Methods Between January 2022 and August 2023, 10 free flaps were used in nine patients (three females and six males) who had previously undergone head and neck reconstruction with PMF. The age of the patients ranged from 54 to 74 years. Seven out of the nine PMFs were previously performed by different surgical teams. Squamous cell carcinoma (SCC) was the reason for primary surgeries in all patients and the PMFs were used for right lower lip and right submandibular defect, left lower lip and mentum defect, lower lip defect, right lower lip and right submandibular defect, right retromolar trigone defect, right buccal defect, left anterolateral esophageal defect, right retromolar trigone defect and left anterolateral pharyngoesophageal defect reconstructions. The problems were partial skin island necrosis and wound dehiscence in six patients and total skin necrosis in three patients. The partial skin island necroses already showed that the pedicles were unproblematic. For patients with total skin island necrosis the muscle stalks so the pedicles were also unproblematic which were confirmed by physical examination and Doppler device. After complications, the finally defects were located in the lower lip, left lower lip and mentum, right lower lip and right submandibular area, left anterolateral esophageal area and left neck, right buccal area, right retromolar trigon, left anterolateral pharyngoesophageal fistula and left neck. The sizes of the defects were between 3 × 4 cm and 11 × 17 cm. For all patients, the pedicle of the previously harvested PMF was used as a recipient for free flaps. Since the PMF was flipped over the clavicula for the reconstruction previously, the pedicle was so close to skin or skin graft which was used for coverage of the muscle stalk. The Doppler device was used first over the clavicle where the PMF was flipped for vessel identification. After marking the vessels, a vertical zigzag incision was made on the skin or skin graft. The perivascular fatty tissue and the pedicle were encountered with minimal dissection by the guidance of Doppler. After meticulous microscopic dissection, the pedicle of PMF was prepared for anastomoses as usual. Six radial forearm free flap (RFFF) and four anterolateral thigh flap (ALT) flaps were used in the head and neck reconstructions for the nine patients. Results The sizes of the flaps were between 4 × 5 cm and 12 × 17 cm. The diameters of the recipient arteries were between 0.9 and 1.2 mm. Recipient veins were approximately the same diameter as the arteries. In one patient, two vein grafts were used for lengthening both the artery and vein to reach recipient vessels. End‐to‐end anastomoses without vein grafts were performed in the remaining patients. One arterial thrombosis that manifested on the first postoperative day was salvaged successfully. Hematoma was seen in two patients and wound dehiscence was seen in three patients. There was no partial or total flap necrosis and all flaps survived. The follow‐up period ranged from 2 to 12 months. Despite successful reconstructions, two patients died during the follow‐up period due to unrelated conditions. Functional results were acceptable in the remaining patients. Conclusion The pedicle of previously used pectoral myocutaneous flaps may be a useful alternative option as the recipient for free flaps in head and neck reconstruction.

Impact of patient position on cystometric parameters in pediatric patients with neurogenic bladder: A prospective study

Aims Urodynamic studies (UDSs) play a crucial role in evaluating lower urinary tract function in pediatric patients with neurogenic bladder. However, the influence of patient position on urodynamic parameters in this population remains understudied. This study aims to investigate the effect of patient position on urodynamic results in children with neurogenic bladder. Methods A prospective study was conducted with 50 pediatric patients diagnosed with neurogenic bladder. Urodynamic recordings were obtained during a single session, with the first two fillings in the supine position and the third filling in the sitting position. Urodynamic parameters assessed included detrusor overactivity (DO), maximum detrusor pressure (MDP), cystometric bladder capacity (CBC), compliance (C), detrusor leak point pressure (DLPP), and bladder volume at the moment of incontinence (DLPV). Results Patient position did not significantly influence CBC, DO, C, and DLPV ( p  > 0.05). However, there were significant differences in MDP and DLPP between the supine and sitting positions ( p  < 0.05), with higher values observed in the supine position. Conclusions These findings highlight the importance of considering the patient's position when interpreting urodynamic results and making treatment decisions for children with neurogenic bladder. The higher MDP and DLPP values in the supine position may have clinical implications for assessing upper urinary tract integrity and treatment planning. However, further research is needed to understand the underlying mechanisms and generalize these findings to broader patient populations.

Utilization of cross‐correlation function for assessment of replication quality in ultrasonic embossing of microchannels on polymethyl methacrylate

Ultrasonic embossing—a process where a horn vibrating at 20–30 kHz compresses on a thermoplastic substrate sitting on a mold to replicate the features on the mold to the substrate—is a promising method for fabricating microchannels on thermoplastics due to reduced cycle time and relatively low equipment cost. Replication quality in ultrasonic embossing has been investigated in the literature by primarily referring to the replication depth. However, this approach does not fully reflect the fidelity between the mold and the replicated feature, especially at the side walls, which are typically designed to be vertical in microchannels. We propose using cross‐correlation—a method that quantifies the similarity between two signals by measuring the overlap of their patterns—between the derivative of the mold profile and the embossed profile as a figure of merit that accurately reflects the fidelity of the side wall. For testing purposes, we embossed straight microchannels on polymethyl methacrylate (PMMA) using micron‐scaled protrusions on a brass mold fabricated by CNC milling. The mold comprised 100, 300, and 1000‐μm‐wide protrusions of same designed height of 300 μm, resulting in aspect ratios (AR) of 3, 1, and 1/3, respectively. Cross‐correlations between the derivatives of the profiles ranged between 0.50 and 1.00, while cross‐correlations between the profiles were greater than 0.97 in all cases, showing the sensitivity imposed by utilizing the derivatives. Setting average of all cross‐correlation values (0.8) as the quality threshold, we observed that high AR (3) features were replicated at low quality, while low AR (1/3) features were replicated at high quality, regardless of the process parameters. In replicating unit AR features, the process parameters were observed to affect the quality, where the combination of vibration time and pressure was the most significant compared to individual effects of the parameters. Highlights Parameters' effect on replication of varied aspect ratio features was assessed. Assessment was carried out by cross‐correlating mold and channel profiles. Cross‐correlating derivatives of profiles provide a more sensitive means. General rules for replication quality in ultrasonic embossing were driven.

A new ring fixator system for automated bone fixation

Background In the field of orthopaedics, external fixators are commonly employed for treating extremity fractures and deformities. Computer‐assisted systems offer a promising and less error‐prone treatment alternative to manual fixation by utilising a software to plan treatments based on radiological and clinical data. Nevertheless, existing computer‐assisted systems have limitations and constraints. Methods This work represents the culmination of a project aimed at developing a new automatised fixation system and a corresponding software to minimise human intervention and associated errors, and the developed system incorporates enhanced functionalities and has fewer constraints compared to existing systems. Results The automatised fixation system and its graphical user interface (GUI) demonstrate promising results in terms of accuracy, efficiency, and reliability. Conclusion The developed fixation system and its accompanying GUI represent an improvement in computer‐assisted fixation systems. Future research may focus on further refining the system and conducting clinical trials.

Domain-Specific Rules Override Aesthetic Graph Drawing Criteria: An Exploration of User-Generated Diagrams

Comparison of supine–prone percutaneous nephrolithotomy methods in the treatment of kidney stones in pediatric patients: prospective randomized study

The Desire for Being Liked and the Fear of Negative Evaluation in Rhinoplasty Patients

Dual-Plane Midface Lift Through Transoral and Transtemporal Approach