Engineering of clarithromycin loaded stimulus responsive dissolving microneedle patches for the treatment of biofilms

This study aimed to fabricate clarithromycin laden Eudragit S-100-based microfibers (MF), microfibers coated film (MB), clarithromycin loaded polyvinyl pyrollidone, hyaluronic acid and sorbitol-based dissolving microneedle patches (CP) and microfibers coated microneedle patches (MP). Morphological and phase analysis of formulations were carried out by scanning electron microscopy and differential scanning calorimetry, X-ray diffraction, respectively. Substrate liquefaction test, in vitro drug release, antimicrobial assay and in vivo antibiofilm studies were performed. MF exhibited a uniform surface and interconnected network. Morphological analysis of CP revealed sharp-tipped and uniform-surfaced microstructures. Clarithromycin was incorporated within MF and CP as amorphous solid. Liquefaction test indicated hyaluronate lyase enzyme responsiveness of hyaluronic acid. Fibers-based formulations (MF, MB and MP) provided an alkaline pH (7.4) responsive drug release; ∼79 %, ∼78 % and ∼81 %, respectively within 2 hours. CP showed a drug release of ∼82 % within 2 hours. MP showed ∼13 % larger inhibitory zone against Staphylococcus aureus (S. aureus) as compared to MB and CP. A relatively rapid eradication of S. aureus in infected wounds and subsequent skin regeneration was observed following MP application as compared to MB and CP indicating its usefulness for the management of microbial biofilms.

Evaluation of sustained-release in-situ injectable gels, containing naproxen sodium, using in vitro, in silico and in vivo analysis

The study aimed to fabricate naproxen sodium loaded in-situ gels of sodium alginate. Different in-situ gel forming solutions of naproxen sodium and sodium alginate were prepared and gel formation was studied in different physiological ions i.e., CaCl₂ and Ca-gluconate. The prepared gel formulations were evaluated for different physical attributes such as gelation time, sol-gel fraction, ATR-FTIR spectroscopy and in silico molecular dynamics (MD) simulations. Drug release studies were carried out in a dialysis membrane using USP dissolution basket apparatus-I. In vivo anti-inflammatory studies were performed in Sprague-Dawley rats having carrageenan-induced hind paw inflammation. Higher polymer concentration in formulations resulted in decreased gelation time and an increased gel fraction. The ATR-FTIR and MD simulation revealed H-bonding between the alginate and naproxen sodium at 3500-3200 cm^-1 with a RMSD of ∼2.8 Å and binding free energy ΔG_{pred (GB)} = -10.93 kcal/mol. In vitro drug release studies from F8CAG suggested a sustained release of naproxen sodium. In vivo studies revealed a continuous decrease in swelling degree (≈-5.28± 0.210 mm) in inflamed hind paw of Sprague-Dawley rats over 96 h. The in-situ gel forming injectable preparation (F8CAG) offers a sustained release of naproxen sodium in the articular cavity which promises the treatment of chronic inflammatory conditions such as arthritis.

A review of emerging technologies enabling improved solid oral dosage form manufacturing and processing

Tablets are the most widely utilized solid oral dosage forms because of the advantages of self-administration, stability, ease of handling, transportation, and good patient compliance. Over time, extensive advances have been made in tableting technology. This review aims to provide an insight about the advances in tablet excipients, manufacturing, analytical techniques and deployment of Quality by Design (QbD). Various excipients offering novel functionalities such as solubility enhancement, super-disintegration, taste masking and drug release modifications have been developed. Furthermore, co-processed multifunctional ready-to-use excipients, particularly for tablet dosage forms, have benefitted manufacturing with shorter processing times. Advances in granulation methods, including moist, thermal adhesion, steam, melt, freeze, foam, reverse wet and pneumatic dry granulation, have been proposed to improve product and process performance. Furthermore, methods for particle engineering including hot melt extrusion, extrusion-spheronization, injection molding, spray drying / congealing, co-precipitation and nanotechnology-based approaches have been employed to produce robust tablet formulations. A wide range of tableting technologies including rapidly disintegrating, matrix, tablet-in-tablet, tablet-in-capsule, multilayer tablets and multiparticulate systems have been developed to achieve customized formulation performance. In addition to conventional invasive characterization methods, novel techniques based on laser, tomography, fluorescence, spectroscopy and acoustic approaches have been developed to assess the physical-mechanical attributes of tablet formulations in a non- or minimally invasive manner. Conventional UV-Visible spectroscopy method has been improved (e.g. fiber-optic probes and UV imaging-based approaches) to efficiently record the dissolution profile of tablet formulations. Numerous modifications in tableting presses have also been made to aid machine product changeover, cleaning, and enhance efficiency and productivity. Various process analytical technologies have been employed to track the formulation properties and critical process parameters. These advances will contribute to a strategy for robust tablet dosage forms with excellent performance attributes.

MONITORING OF HIGH-ENERGY PHOTON FLUENCE IN CLINAC USING Zn AND Cr PHOTOACTIVATION

Monitoring of high-energy photon dose in radiation therapy is crucial for radiation protection, as well as to estimate the radiation effects in the operating microelectronic devices. The aim of this work was to investigate the possibility of using the photoactivation technique to monitor the high-energy photon fluence in the Varian 21EX 23MV CLINAC. The 52Cr(γ,n)51Cr and 66Zn(γ,n)65Zn reactions were used. It was found that 51Cr and 65Zn can be used successfully to monitor the fluence for short term (80 days) and long term (110 days), respectively.

Neutron and high energy photon fluence estimation in CLINAC using gold activation foils

Aim

The thermal neutron, epithermal neutron and high-energy photon fluence were measured in this work around the Varian 21EX 23 MV CLINAC, which is operated in Albairouni hospital in Damascus, Syria.

Background

Photoneutron measurements around medical CLINAC aim to protect both patients and staff from unwanted radiation.

Materials and methods

Neutron and photon activation techniques were applied using gold foils.

Results

It was found that high-energy photons fluence has practically a constant value in the field size. The thermal and epithermal neutron fluence along ox and oy axes has the same order of magnitude.

Conclusion

Gold foils have been used successfully to measure neutron flux and high-energy photons simultaneously using activation techniques.

Determination of 226Ra Contamination Depth Around Phosphogypsum Pit Using In-Situ Gamma Spectrometer

The feasibility of applying multiple photopeak method (MPM) and peak to valley ratio (PVRM) method to determine Radium-226 contamination depth (²²⁶Ra h_c) has been investigated. Gamma spectra in eight positions around phosphogypsum disposal pit has been measured using portable NaI(Tl) gamma spectrometer. MPM was investigated by calculating the ratio [Formula: see text] of 609 keV gamma line net counts to the corresponding value of 352 keV. PVRM was investigated by calculating the ratio [Formula: see text] of net counts of 609 keV gamma line to the corresponding valley counts. ²²⁶Ra h_c in the positions has been determined using traditional soil coring. It was found that, [Formula: see text] and [Formula: see text] have good linear correlations with ²²⁶Ra h_cTherefore, ²²⁶Ra h_c can be determined by MPM and PVRM. These methods save a lot of time, costs and efforts in comparison with the traditional one.

Survey of Hepatitis Markers Among Donors in the State of Qatar

A total of 78,428 blood units collected by the Blood Donor Unit, Hamad Medical Corporation, Doha, from the multinational donors of Qatar (28,622 Qatari nationals donors and 49,806 Non-Qatari donors) in the period January 1994 to Dececember 2001 were screened for hepatitis markers. About 10,382 units (13.2%) were discarded because of positivity for one or more hepatitis markers; 769 units (0.9%) were positive for hepatitis-B surface antigen (HBsAg), 8516 units (10.9%) were positive for hepatitis-B core antibodies (HBcAb) and 1097 units (1.39%) were positive for hepatitis C (HCV) antibodies. There was no significant difference between the rate of positivity for HBcAb and HBsAg in indigenous Qataris and Non-Qataris despite a slightly higher rate ofpositivity for HCV antibodies in the Non-Qatari group. An outstanding finding was the significantly high rate of positivity for HCV antibodies in Egyptian donations (11.2%), which accounted for 31.2% of all discards for the Non-Qatari group. As the Blood Donor Unit at HMC is the only blood collection center in Qatar it is assumed that the results could be representative of the country as a whole.

Improved Screening of Donor's Blood for Malaria: A Qatari Experience

Malaria is one of the most widespread infections globally and is undoubtedly responsible for the majority of all cases of transfusion-transmitted disease in the world. Qatar is free from endemic malaria. However; cases are seen with the large expatriate work force imported from malarious areas. These constitute a significant percent of the blood donors’ pool (34%). Over a 27-month period, among 5845 volunteers tested for malaria, 21 were deferred (0.36%) showing positive result when screened by the Giemsastained thick smear technique, with 2 undiagnosed cases that led to transfusion-transmitted malaria. Since then and for the last 21 months, the Falciparum-Spot immunofluorescence (IF) test was implemented in an attempt to ensure accurate screening. Among 6367 donors tested, 274 (4.3%) were deferred. Careful questioning about donor travel history, expansion of deferral policy and the use of a more sensitive screening test have all resulted in increasing layers of safety where no transfusion-transmitted malaria was reported in the last 21 months. These measures were necessary to regain the trust of the public in the safety and stewardship of the blood supply.

Water enhanced "non-paralytic" transcutaneous ultrasound of the normal gastric wall layers (WETCUS)

BACKGROUND/AIMS

Barium studies, endoscopies and endoscopic ultrasound are the usual methods for gastrointestinal tract examinations. Endoscopic ultrasound was the only accurate equipment used for imaging the various layers of the stomach wall distinctly.

METHODOLOGY

Twenty patients undergoing renal ultrasound were given 600 cc of water to drink. Gastric wall layers were demonstrated in all patients, namely mucosa; submucosa, musculosa and serosa. The echogenic layer of the water-mucosa interface was not included in gastric wall thickness measurement.

RESULTS

The normal wall measurement varied from 3-5 mm. This is lower than in previous reports.

CONCLUSIONS

Water enhanced "non-paralytic" transcutaneous ultrasound is a simple, safe, non-invasive, and accurate test for visualizing gastric wall layers.

Needle track seeding following percutaneous ethanol injection for treatment of hepatocellular carcinoma

We report two cases of needle track seeding in the subcutaneous tissue and intercostal muscles following percutaneous ethanol injection for the treatment of hepatocellular carcinoma. In one patient, tumor seeding was observed 11 months after a total of 12 alcohol injections, and in the other patient, tumor seeding was observed 30 months after a total of 18 alcohol injections. The cases reported in the literature are discussed.