MyMedR

Displaying all 5 publications

Abstract:

Sort:

Fulltext Inflammatory Responses in Oro-Maxillofacial Region Expanded Using Anisotropic Hydrogel Tissue Expander

Ali Salim KM, Abd Jalil A, Radzi Z, Ismail SM, Czernuszka JT, Rahman MT

Materials (Basel), 2020 Oct 06;13(19).
PMID: 33036128 DOI: 10.3390/ma13194436

OBJECTIVE: Reconstruction of oral and facial defects often necessitate replacement of missing soft tissue. The purpose of tissue expanders is to grow healthy supplementary tissue under a controlled force. This study investigates the inflammatory responses associated with the force generated from the use of anisotropic hydrogel tissue expanders.
METHODS: Sprague Dawley rats (n = 7, body weight = 300 g ± 50 g) were grouped randomly into two groups-control (n = 3) and expanded (n = 4). Anisotropic hydrogel tissue expanders were inserted into the frontal maxillofacial region of the rats in the expanded group. The rats were sacrificed, and skin samples were harvested, fixed in formalin, and embedded in paraffin wax for histological investigation. Hematoxylin and eosin staining was performed to detect histological changes between the two groups and to investigate the inflammatory response in the expanded samples. Three inflammatory markers, namely interleukin (IL)-1α, IL-6, and tumor necrosis factor-α (TNF-α), were analyzed by immunohistochemistry.
RESULT: IL-1-α expression was only observed in the expanded tissue samples compared to the controls. In contrast, there was no significant difference in IL-6, and TNF-α production. Histological analysis showed the absence of inflammatory response in expanded tissues, and a negative non-significant correlation (Spearman's correlation coefficient) between IL-1-α immune-positive cells and the inflammatory cells (r = -0.500). In conclusion, tissues that are expanded and stabilized using an anisotropic self-inflating hydrogel tissue expander might be useful for tissue replacement and engraftment as the expanded tissue does not show any sign of inflammatory responses. Detection of IL-1-α in the expanded tissues warrants further investigation for its involvement without any visible inflammatory response.
Seizure severity assessment tools for adult epilepsy patients: A systematic review

Rusli RA, Makmor Bakry M, Mohamed Shah N, Hui Jan T

Epilepsy Behav, 2023 Mar 29;142:109154.
PMID: 37001468 DOI: 10.1016/j.yebeh.2023.109154

INTRODUCTION: Seizure outcomes from antiseizure medication (ASM) therapy can be measured across various domains using assessment tools. The available tools may contain an array of different components or items. Seizure severity assessment, as opposed to seizure frequency count may have been a more accurate measurement in determining the effectiveness of ASM therapy. This study aimed to review studies developing seizure severity assessment tools for adults with epilepsy, describe the development methods and validation, and compare the list of items in these tools.
METHODS: The systematic search utilized established databases such as Scopus, Ovid, Web of Science, Medline, Wiley Online, and Cochrane Library. Studies published from inception to December 15, 2022, were selected. Publications describing the development of tools to measure seizure severity among adult epilepsy patients were included. Outcome measures including the tool's content, development methods, validity, and reliability assessments were compared.
RESULTS: The search produced eight publications describing the development of eight seizure severity assessment tools. One of these tools is part of a multidimensional assessment of the overall impact of epilepsy. The frequently used method in the initial development was the qualitative method (n = 6) where two publications reanalyzed the items from previous studies. Face validity was the most common validation test conducted (n = 4). At least one reliability assessment was conducted for each of the tools, most commonly by the test-retest method (n = 6) and inter-rater reliability (n = 5). All of these tools cover the components of pre-ictal (warning/aura), ictal, and postictal (recovery) events.
CONCLUSION: The identified tools described the assessment of seizure severity using various subscales. The emergence of new methods in quantifying seizure severity unfolds opportunities in discovering more comprehensive assessments of seizure severity in both clinical trials and daily clinical practice.
Characteristics and Young's Modulus of Collagen Fibrils from Expanded Skin Using Anisotropic Controlled Rate Self-Inflating Tissue Expander

Manssor NA, Radzi Z, Yahya NA, Mohamad Yusof L, Hariri F, Khairuddin NH, et al.

Skin Pharmacol Physiol, 2016;29(2):55-62.
PMID: 26836267 DOI: 10.1159/000431328

Mechanical properties of expanded skin tissue are different from normal skin, which is dependent mainly on the structural and functional integrity of dermal collagen fibrils. In the present study, mechanical properties and surface topography of both expanded and nonexpanded skin collagen fibrils were evaluated. Anisotropic controlled rate self-inflating tissue expanders were placed beneath the skin of sheep's forelimbs. The tissue expanders gradually increased in height and reached equilibrium in 2 weeks. They were left in situ for another 2 weeks before explantation. Expanded and normal skin samples were surgically harvested from the sheep (n = 5). Young's modulus and surface topography of collagen fibrils were measured using an atomic force microscope. A surface topographic scan showed organized hierarchical structural levels: collagen molecules, fibrils and fibers. No significant difference was detected for the D-banding pattern: 63.5 ± 2.6 nm (normal skin) and 63.7 ± 2.7 nm (expanded skin). Fibrils from expanded tissues consisted of loosely packed collagen fibrils and the width of the fibrils was significantly narrower compared to those from normal skin: 153.9 ± 25.3 and 106.7 ± 28.5 nm, respectively. Young's modulus of the collagen fibrils in the expanded and normal skin was not statistically significant: 46.5 ± 19.4 and 35.2 ± 27.0 MPa, respectively. In conclusion, the anisotropic controlled rate self-inflating tissue expander produced a loosely packed collagen network and the fibrils exhibited similar D-banding characteristics as the control group in a sheep model. However, the fibrils from the expanded skin were significantly narrower. The stiffness of the fibrils from the expanded skin was higher but it was not statistically different.
Biomechanical Effects of Unidirectional Expansion Using Anisotropic Expanders in Horse Skin Tissue

Al-Majhali SH, Khairuddin NH, Abdul Razak IS, Radzi Z, Rahman MT, Sapalo JT, et al.

J Equine Vet Sci, 2021 04;99:103399.
PMID: 33781409 DOI: 10.1016/j.jevs.2021.103399

The use of a self-inflating tissue expander is a technique to stretch cutaneous tissues for potential use in reconstructive skin surgeries. This study investigates the mechanical properties of horse skin stretched by the subcutaneous implantation of anisotropic tissue expanders at the forehead, right shoulder, and dorsomedial part of the cannon region of the right forelimb in six (n = 6) horses. After 14 days of skin expansion, expanded and normal (control) skin samples were harvested and their mechanical properties of elastic modulus (EM), maximum force (MF), maximum stress (MSs) and maximum strain (MSr) were evaluated using uniaxial tension test. The expanded skin from shoulder area has higher EM, MSs, MSr and MF than the normal skin when compared to the forehead and lower forelimb. Statistically, there was a significant (P= .02) mean difference for MSs between the expanded shoulder and lower forelimb skin, but the pairwise comparison of EM, MSr and MF showed no significant difference between the locations. The overall effect of locations on EM and MSs was statistically significant (P < .05), however, there was no overall effect of horse factor, treatment factor (normal and expanded skin) and location interaction on the EM, MSS, MF and MSr. In conclusion, the expanded skin from the frontal head and the distal limb are less elastic (stiffer) compared to that of the expanded skin of the shoulder, thus anatomical location of the skin has some degree of effect on EM and MSs.
Fulltext Phylogenomics and the rise of the angiosperms

Zuntini AR, Carruthers T, Maurin O, Bailey PC, Leempoel K, Brewer GE, et al.

Nature, 2024 May;629(8013):843-850.
PMID: 38658746 DOI: 10.1038/s41586-024-07324-0

Angiosperms are the cornerstone of most terrestrial ecosystems and human livelihoods1,2. A robust understanding of angiosperm evolution is required to explain their rise to ecological dominance. So far, the angiosperm tree of life has been determined primarily by means of analyses of the plastid genome3,4. Many studies have drawn on this foundational work, such as classification and first insights into angiosperm diversification since their Mesozoic origins5-7. However, the limited and biased sampling of both taxa and genomes undermines confidence in the tree and its implications. Here, we build the tree of life for almost 8,000 (about 60%) angiosperm genera using a standardized set of 353 nuclear genes8. This 15-fold increase in genus-level sampling relative to comparable nuclear studies9 provides a critical test of earlier results and brings notable change to key groups, especially in rosids, while substantiating many previously predicted relationships. Scaling this tree to time using 200 fossils, we discovered that early angiosperm evolution was characterized by high gene tree conflict and explosive diversification, giving rise to more than 80% of extant angiosperm orders. Steady diversification ensued through the remaining Mesozoic Era until rates resurged in the Cenozoic Era, concurrent with decreasing global temperatures and tightly linked with gene tree conflict. Taken together, our extensive sampling combined with advanced phylogenomic methods shows the deep history and full complexity in the evolution of a megadiverse clade.