Search

Australian Blackwood is known to be an important cause of allergic contact dermatitis in Australia. Previous investigations have shown that 2,6-dimethoxy-1,4-benzoquinone and acamelin are 2 of the responsible, but weak, sensitizers. When these 2 quinones are lacking, which is occasionally found, the wood still possesses allergenic properties. The present re-examination led to the isolation and identification of 4 hydroxyflavans, of which 3 proved to be allergens. Melacacidin, known to be the main constituent of these flavan derivatives in the heartwood, was isolated and its sensitizing capacity in guinea pigs determined. It showed a moderate sensitizing power. Melacacidin occurs abundantly in 125 Australian and 3 African Acacia species. [ABSTRACT FROM AUTHOR]

A 15-year-old girl developed perioral dermatitis and swelling of the lips, having played a flute made of cocus wood for 2 years. Patch tests with wood shavings, as well as with subsequently isolated constituents named Cocus I and Cocus II, were strongly positive. After complete purification, both contact allergens were identified as isoflavan derivatives. While Cocus I was shown to be 7, 8-dihydroxy-2', 4', 5'-trimethoxyisoflavan, the structure of Cocus II could not be elucidated exactly. It could have been either 7, 8, 3'-trihydroxy-2', 4'-dimethoxyisoflavan or 7, 8, 2'-trihydroxy-3', 4'-dimethoxyflavan. The exact position of the hydroxy and methoxy group in C-2' and C-3' can be determined only by complete synthesis of both compounds or by isolation of greater amounts of Cocus II for further oxidation experiments. Due to the stronger patch test reaction and the higher yield of Cocus I in the wood, this hydroxyisoflavan must be recognized as the main contact allergen. [ABSTRACT FROM AUTHOR]

Experimental and chemical investigations revealed that common ivy (Hedera helix susp. helix) contains 3 compounds which are powerful irritants and moderate sensitizers. Only 2 of these constituents, falcarinol and didehydrofalcarinol, are present in the plant during the whole year. Besides Panax ginseng and Srchfflera arboricala, this is the third species of the Araliaceae in which these polyacetylenic sensitizers have been found. Falcarinol and didehydrofalcarinol also occur in Hedera helix subsp canariensis, 4 patients have been patch tested. Even in low concentrations (0.03%). the main allergin falcarinol elicited strong reactions in all of them. One of the authors became sensitized during the investigations. [ABSTRACT FROM AUTHOR]

A variety of parameters is available to assess the efficacy of oral antiseptics. Most study protocols select the parameters according to the specific study goal or according to preferences of the researchers. Beside general recommendations for home-use studies, no recommendations exist for other study types. Therefore, pre-selected parameters should be compared within several study designs and the most suitable parameters should be recommended for further application. The following parameters were selected before study start: plaque indices (PlI, Silness & Loe 1964, M-QHI, Turesky et al. 1970), plaque area (PlA), bacterial vitality (BV, Netuschil et al. 1989), gingivitis indices (GI, Loe 1967; M-GI, Lobene et al. 1986; BOP, Ainamo & Bay 1975), gingival crevicular fluid, colony forming units, and the discoloration index (DI, Brecx et al. 1993). The parameters were applied in four study designs: eight-hour substantivity studies, four-day plaque re-growth studies, 21-day experimental gingivitis studies, and six-month home-use studies. Pearson correlation coefficients were computed. The highest correlations were found between PlI and M-QHI and between GI and M-GI (p<0.01) in all corresponding studies and treatment groups. Few middle correlations existed between BOP and the other gingival indices. Neither GI nor M-GI correlated with GCF nor did BV with plaque indices. Inconsistent correlations were obtained between PlA and plaque indices and between PlI and GI. It is concluded, that primary parameters for these designs should be one plaque index and/or one gingivitis index to monitor plaque and gingivitis. The other parameters did not yield additional information about the study outcome.

In the literature and in the daily study routine, a wide range of study designs exists to test the efficacy of mouthrinses. Within these various designs, a considerable number of parameters is applied. Due to the different protocols currently used the outcome of these investigations is hardly to compare. Therefore, it was the aim of the present investigation to assess suitable study designs of different durations, to select and compare parameters, and to find suitable study participants in order to finally recommend more standardized protocols for future studies on oral antiseptics. Eight-hour substantivity studies, four-day plaque re-growth studies, 21-day experimental gingivitis studies, and six-month home-use studies were performed either cross-over or parallel. The clinical studies were randomized, controlled, and investigator-blinded. From most often applied clinical and laboratory parameters, two plaque indices, bacterial vitality, three gingivitis indices, gingival crevicular fluid, colony forming units, and the discoloration index were selected to assess plaque inhibition, gingivitis development, tooth staining, and possible bacterial shifts in the oral cavity. Four or five, respectively, treatment groups were formed that rinsed with the following solutions: chlorhexidine digluconate 0.06%, 0.12%, 0.20%, amine fluoride/stannous fluoride, and a negative control. In addition, all study designs were tested on two different study populations. Population alpha consisted of persons who had a gingival index <0.8 while population beta participants presented a mean gingival index of >/=0.8. Pearson correlation coefficients were calculated between parameters and between subsets of teeth and full-mouth recording. T-tests were applied to compare between populations alpha and beta.

This article demonstrates the ability of electron diffraction (3D ED, or simply ED) for solving complex structures of active pharmaceutical ingredients (API) and its relevance in the drug development process. The study focuses on febuxostat (FEB), a selective inhibitor used for treating gout. FEB exhibits multiple solid forms, with the crystal structure of the marketed polymorph (form A) being unknown despite its commercial availability. In this work, the crystal structure of form A was successfully determined using both ED and single-crystal X-ray diffraction techniques (SC-XRD). Notably, the crystal growth attempts delivered very small crystals, suitable for ED only, while larger single-crystals for SC-XRD were unintentionally obtained in an experiment aiming for the co-crystallization of FEB with benzoic acid. The results show that ED is a valuable and reliable tool for crystal structure determinations, with comparable accuracy to X-ray crystallography. This study highlights the possibility of incorporating ED in the pharmaceutical research and development process, offering a reliable and efficient approach for crystal structure analysis. It emphasizes the significance of combining crystal structure knowledge with theoretical methods in understanding complex polymorphic systems. Furthermore, it addresses the ED potential in overcoming the challenges in characterizing solid forms across the drug development process. [ABSTRACT FROM AUTHOR]

Mechanical ventilation exposes the lung to injurious stresses and strains that can negatively affect clinical outcomes in acute respiratory distress syndrome or cause pulmonary complications after general anesthesia. Excess global lung strain, estimated as increased respiratory system driving pressure, is associated with mortality related to mechanical ventilation. The role of small-dimension biomechanical factors underlying this association and their spatial heterogeneity within the lung are currently unknown. Using four-dimensional computed tomography with a voxel resolution of 2.4 cubic millimeters and a multiresolution convolutional neural network for whole-lung image segmentation, we dynamically measured voxel-wise lung inflation and tidal parenchymal strains. Healthy or injured ovine lungs were evaluated as the mechanical ventilation positive end-expiratory pressure (PEEP) was titrated from 20 to 2 centimeters of water. The PEEP of minimal driving pressure (PEEPDP) optimized local lung biomechanics. We observed a greater rate of change in nonaerated lung mass with respect to PEEP below PEEPDP compared with PEEP values above this threshold. PEEPDP similarly characterized a breaking point in the relationships between PEEP and SD of local tidal parenchymal strain, the 95th percentile of local strains, and the magnitude of tidal overdistension. These findings advance the understanding of lung collapse, tidal overdistension, and strain heterogeneity as local triggers of ventilator-induced lung injury in large-animal lungs similar to those of humans and could inform the clinical management of mechanical ventilation to improve local lung biomechanics. Editor's summary: Mechanical ventilation is a life-sustaining tool for patients with compromised lungs but is also associated with a risk of damaging lung strain. Several ventilation parameters can be tuned by clinicians, including the amount of pressure applied at the end of expiration to maintain open alveoli [positive end-expiratory pressure (PEEP)]. The relationship between applied PEEP and small-scale lung strains is not well characterized. Here, Lagier et al. used four-dimensional computed tomography imaging with 2.4 mm3 voxel resolution in mechanically ventilated sheep to analyze localized changes in lung strain in healthy lungs and diseased lungs. They identified the PEEP of minimal respiratory driving pressure as a setting that marks a change in the relationship between PEEP settings and parameters of lung function and biomechanics. These findings will support future investigation in individualized mechanical ventilation. —Molly Ogle [ABSTRACT FROM AUTHOR]

Dental plaque bacteria play an important role in the pathogenicity of periodontitis and peri-implantitis. Therefore, antimicrobial agents are one means of treatment. N-chlorotaurine (NCT) as an endogenous well-tolerated topical antiseptic could be of advantage for this purpose. Accordingly, its microbicidal activity against some dental plaque bacteria was investigated at therapeutic concentrations in vitro. In quantitative killing assays, the activity of NCT against planktonic bacteria and against biofilms grown for 48 h on implantation screws was tested. Electron microscopy was used to demonstrate the formation of biofilm and its morphological changes. The killing of planktonic bacteria of all tested species, namely Streptococcus sanguinis, Streptococcus salivarius, Streptococcus oralis, Streptococcus cristatus, Rothia aeria, and Capnocytophaga ochracea, was shown within 10–20 min by 1% NCT in 0.01 M phosphate-buffered saline at 37 °C. Bacteria grown on screws for 24 h were inactivated by 1% NCT after 15–20 min as well, but the formation of biofilm on the screws was visible in electron microscopy not before 48 h. The killing of biofilms by 1% NCT was demonstrated after 30 min (streptococci) and 40 min (R. aeria). As expected, NCT has broad activity against dental plaque bacteria as well and should be further investigated on its clinical efficacy in periodontitis and peri-implantitis. [ABSTRACT FROM AUTHOR]

Featured Application: The use of a cymenol-based mouth rinse is safe and well-tolerated by patients, with no reports of side effects or adverse events. The aim of this study was to evaluate a newly formulated mouth rinse containing cymenol in patients undergoing supportive periodontal care in terms of safety (primary outcome) and the impact on dental biofilm and gingival inflammation (secondary outcomes). This research was designed as a pilot, controlled, randomized, parallel, triple-blinded, single-center, clinical trial of a 12-week duration. Adverse events and product perception were assessed by a questionnaire. Clinical, patient-reported outcomes (PROs), compliance, tooth staining, dentin hypersensitivity and microbiological variables were also evaluated. Student T, Mann–Whitney-U and Chi-square tests were applied. Thirty participants (15 per group) were included, randomized and followed for 12 weeks. No adverse events were reported. The questionnaire showed an overall rating of 7.2 (out of 10) in the experimental group and of 8.2 in the control group (p = 0.165) at 12 weeks. No statistically significant differences were observed in terms of gingival health, tooth staining, dentin hypersensitivity or microbiological outcomes between groups at baseline, 6- and 12-week visits. The adjuvant use of the new mouth rinse formulation proved to be as safe as the control product and no significant differences were observed in terms of clinical efficacy. [ABSTRACT FROM AUTHOR]

Objectives: Reflecting the need for an effective support for the daily oral hygiene routine of patients experiencing (symptoms of) gum inflammation, a new mouthwash has been developed containing an amine + zinc lactate + fluoride system. The in vitro efficacy of this product was assessed using traditional laboratory methods, as well as novel experimentation. Materials and Methods: This mouthwash has been evaluated in a series of laboratory tests including two short interval kill tests (SIKTs), a 12‐h (longer term) biofilm regrowth assay, a plaque glycolysis assay, and an aerobic, repeated exposure biofilm model, as well as tests for soft tissue uptake and LPS neutralization. Results: Several laboratory studies demonstrate that a mouthwash containing an amine + zinc lactate + fluoride system provides short‐term and long‐term antibacterial activity. While the immediate efficacy of this formula has been shown to be driven by the presence of the amine, zinc lactate provides a long‐term antibacterial effect, as well as is able to inhibit bacterial metabolism. Conclusions: This research provides the basis for understanding the mode of action of this new mouthwash formulation and explains the previously observed clinical efficacy of this formula against plaque and gingivitis. [ABSTRACT FROM AUTHOR]

Periodontal disease is a multifactorial pathogenic condition involving microbial infection, inflammation, and various systemic complications. Here, a systematic and comprehensive review discussing key-points such as the pros and cons of conventional methods, new advancements, challenges, patents and products, and future prospects is presented. A systematic review process was adopted here by using the following keywords: periodontal diseases, pathogenesis, models, patents, challenges, recent developments, and 3-D printing scaffolds. Search engines used were "google scholar", "web of science", "scopus", and "pubmed", along with textbooks published over the last few decades. A thorough study of the published data rendered an accurate and deep understanding of periodontal diseases, the gap of research so far, and future opportunities. Formulation scientists and doctors need to be interconnected for a better understanding of the disease to prescribe a quality product. Moreover, prime challenges (such as a lack of a vital testing model, scarcity of clinical and preclinical data, products allowing for high drug access to deeper tissue regions for prolonged residence, lack of an international monitoring body, lack of 4D or time controlled scaffolds, and lack of successful AI based tools) exist that must be addressed for designing new quality products. Generally, several products have been commercialized to treat periodontal diseases with certain limitations. Various strategic approaches have been attempted to target certain delivery regions, maximize residence time, improve efficacy, and reduce toxicity. Conclusively, the current review summarizes valuable information for researchers and healthcare professional to treat a wide range of periodontal diseases. [ABSTRACT FROM AUTHOR]

Copyright of Fenerbahce University Journal of Health Sciences (FBU-JOSH) / Fenerbahçe Üniversitesi Sağlık Bilimleri Dergisi is the property of Fenerbahce University Journal of Health Sciences (FBU-JOSH) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Assuming that the streamlines are given by keeping constant one of the two orthogonal curvilinear coordinates in the Euclidean two-dimensional space, while considering a steady, two-dimensional, isentropic flow of an ideal gas through a convergent-divergent nozzle, and thus parallel to the curvilinear upper and lower walls of the nozzle, the theory of differential geometry together with the balance equations of physics was used to study the existence (or non-existence !) of real-valued, differentiable and integrable mass-density solutions to the problem, by means of analytical solutions, and corresponding to an expansion or compression of the gas along the streamlines. Thus, by initially assuming that the partial mass-density derivatives with respect to both curvilinear coordinates satisfy the integrability condition of Schwarz, the resulting system of four scalar partial differential equations led to an analytically derived quadratic equation for the determination of the ideal-gas mass density, based on generalised orthogonal curvilinear coordinates: Finally, the four orthogonal curvilinear coordinate systems, defined by the Killing two-tensors for the Euclidean two-dimensional space, were used, in order to examine whether these coordinate systems could satisfy the already mentioned generalised curvilinear-geometry equation as a quadratic equation, and the related requirements with regard to the partial mass-density derivatives, or not. Only real and nonzero, positive values for the mass density were considered, based on curvilinear streamlines of nonzero curvature. [ABSTRACT FROM AUTHOR]

The past decade has witnessed remarkable progress in cocrystal research, by virtue of the desires to address problematic properties of drugs. Notwithstanding the rapid advancements in knowledge-based cocrystal design, such as by leveraging different in silico virtual screening tools, obtaining false-positive results wherein predicted cocrystals fail to materialize experimentally remains a common occurrence. While being less disconcerting than the false-negative, there is a need to comprehend the underlying reasons as to why cocrystal formers bearing supramolecular features that indicate a high probability of cocrystallization would eventually fail. This enigma is associated with the thermodynamic instability of cocrystals or requirement of a high activation energy for cocrystallization, thus rendering them elusive under conventional production. This review aims to address this knowledge gap by providing a holistic overview on the strategic design and preparation of elusive cocrystals, followed by highlighting the importance of process control on the critical factors, such as reaction kinetics, the presence of catalysts, and annealing conditions. The challenges pertaining to the characterization and clinical translation of elusive cocrystals are also covered. Finally, an empirical analysis of the Cambridge Structural Database was conducted to explore the elusive cocrystal formation through understanding the differential cocrystallization behaviors among a series of isomers and structurally similar coformers. The insights gained herein offer scientists a guide for conducting cocrystal screening in a more rational and effective manner, with the ultimate goal of expediting the development of novel drug cocrystals for future clinical use. [ABSTRACT FROM AUTHOR]

The article informs about American Journal of Respiratory and Critical Care Medicine expresses gratitude to the diligent reviewers who contributed their expertise to manuscript evaluation from January to December 2023. Topic include the extensive list includes professionals from various disciplines, showcasing their commitment to maintaining the journal's high standards through thorough review and analysis.