Epidermal Layer Research Articles

Dermatologic Changes in Experimental Model of Long COVID.

The coronavirus disease-19 (COVID-19) pandemic, declared in early 2020, has left an indelible mark on global health, with over 7.0 million deaths and persistent challenges. While the pharmaceutical industry raced to develop vaccines, the emergence of mutant severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) strains continues to pose a significant threat. Beyond the immediate concerns, the long-term health repercussions of COVID-19 survivors are garnering attention, particularly due to documented cases of cardiovascular issues, liver dysfunction, pulmonary complications, kidney impairments, and notable neurocognitive deficits. Recent studies have delved into the pathophysiological changes in various organs following post-acute infection with murine hepatitis virus-1 (MHV-1), a coronavirus, in mice. One aspect that stands out is the impact on the skin, a previously underexplored facet of long-term COVID-19 effects. The research reveals significant cutaneous findings during both the acute and long-term phases post-MHV-1 infection, mirroring certain alterations observed in humans post-SARS-CoV-2 infection. In the acute stages, mice exhibited destruction of the epidermal layer, increased hair follicles, extensive collagen deposition in the dermal layer, and hyperplasticity of sebaceous glands. Moreover, the thinning of the panniculus carnosus and adventitial layer was noted, consistent with human studies. A long-term investigation revealed the absence of hair follicles, destruction of adipose tissues, and further damage to the epidermal layer. Remarkably, treatment with a synthetic peptide, SPIKENET (SPK), designed to prevent Spike glycoprotein-1 binding with host receptors and elicit a potent anti-inflammatory response, showed protection against MHV-1 infection. Precisely, SPK treatment restored hair follicle loss in MHV-1 infection, re-architected the epidermal and dermal layers, and successfully overhauled fatty tissue destruction. These promising findings underscore the potential of SPK as a therapeutic intervention to prevent long-term skin alterations initiated by SARS-CoV-2, providing a glimmer of hope in the battle against the lingering effects of the pandemic.

The Mechanism of 5-Fluorouracil-Induced Hyperpigmentation in HRM-2 Hairless Mice: Focus on the Increase of Blood Vessels.

5-Fluorouracil (5-FU), an effective chemotherapeutic agent for many solid tumors, has long been reported to cause pigmentation in patients treated intravenously, which occurs with increasing frequency of administration and decreases the QOL of the patients. Although melanin accumulation is thought to be the cause, the mechanism of pigmentation induced by 5-FU administration remains unclear, and there is no effective treatment for this problem. In this study, we investigated the mechanism of pigmentation induced by continuous 5-FU administration in 9-week-old male HRM-2 hairless mice for 8 weeks by focusing on the blood vessels for basic verification. In the auricular skin of 5-FU-administered mice, hyperpigmentation caused by melanin accumulation was observed macroscopically and by Fontana-Masson Staining. In addition, the expression of tyrosinase, melanin synthase, and blood vessel markers in the auricular skin was increased by 5-FU-administration in mice auricular skin. Other anticancer agents, cytarabine (Ara-C) and irinotecan (CPT-11), were also administered, and the differences between them and 5-FU were investigated; these changes were not observed in the auricles of these mice. These results suggest that tyrosinase is associated with 5-FU-induced melanin production and that an increase in blood vessels may be involved. Furthermore, pigmentation with melanin accumulation in the basal epidermal layer is a characteristic finding of 5-FU compared with Ara-C and CPT-11. In conclusion, this study indicates that 5-FU causes hyperpigmentation by melanin accumulation in a characteristic manner, including an increase in blood vessels.

Calcium transients trigger switch-like discharge of prostaglandin E2 in an extracellular signal-regulated kinase-dependent manner.

Prostaglandin E2 (PGE2) is a key player in a plethora of physiological and pathological events. Nevertheless, little is known about the dynamics of PGE2 secretion from a single cell and its effect on the neighboring cells. Here, by observing confluent Madin-Darby canine kidney (MDCK) epithelial cells expressing fluorescent biosensors, we demonstrate that calcium transients in a single cell cause PGE2-mediated radial spread of PKA activation (RSPA) in neighboring cells. By in vivo imaging, RSPA was also observed in the basal layer of the mouse epidermis. Experiments with an optogenetic tool revealed a switch-like PGE2 discharge in response to the increasing cytoplasmic Ca2+ concentrations. The cell density of MDCK cells correlated with the frequencies of calcium transients and the following RSPA. The extracellular signal-regulated kinase (ERK) activation also enhanced the frequency of RSPA in MDCK and in vivo. Thus, the PGE2 discharge is regulated temporally by calcium transients and ERK activity.

Calcium transients trigger switch-like discharge of prostaglandin E2 in an extracellular signal-regulated kinase-dependent manner

Prostaglandin E2 (PGE2) is a key player in a plethora of physiological and pathological events. Nevertheless, little is known about the dynamics of PGE2 secretion from a single cell and its effect on the neighboring cells. Here, by observing confluent Madin–Darby canine kidney (MDCK) epithelial cells expressing fluorescent biosensors, we demonstrate that calcium transients in a single cell cause PGE2-mediated radial spread of PKA activation (RSPA) in neighboring cells. By in vivo imaging, RSPA was also observed in the basal layer of the mouse epidermis. Experiments with an optogenetic tool revealed a switch-like PGE2 discharge in response to the increasing cytoplasmic Ca2+ concentrations. The cell density of MDCK cells correlated with the frequencies of calcium transients and the following RSPA. The extracellular signal-regulated kinase (ERK) activation also enhanced the frequency of RSPA in MDCK and in vivo. Thus, the PGE2 discharge is regulated temporally by calcium transients and ERK activity.

Photobiomodulation and conditioned medium of adipose-derived stem cells for enhancing wound healing in rats with diabetes: an investigation on the proliferation phase.

This investigation tried to evaluate the combined and solo effects of photobiomodulation (PBM) and conditioned medium derived from human adipose tissue-derived stem cells (h-ASC-CM) on the inflammatory and proliferative phases of an ischemic infected delayed healing wound model (IIDHWM) in rats with type I diabetes mellitus (TIDM). The present investigation consisted of four groups: group 1 served as the control, group 2 treated with h-ASC-CM, group 3 underwent PBM treatment, and group 4 received a combination of h-ASC-CM and PBM. Clinical and laboratory assessments were conducted on days 4 and 8. All treatment groups exhibited significantly higher wound strength than the group 1 (p = 0.000). Groups 4 and 3 demonstrated significantly greater wound strength than group 2 (p = 0.000). Additionally, all therapeutic groups showed reduced methicillin -resistant Staphylococcus aureus (MRSA) in comparison with group 1 (p = 0.000). While inflammatory reactions, including neutrophil and macrophage counts, were significantly lower in all therapeutic groups rather than group 1 on days 4 and 8 (p < 0.01), groups 4 and 3 exhibited superior results compared to group 2 (p < 0.01). Furthermore, proliferative activities, including fibroblast and new vessel counts, as well as the measurement of new epidermal and dermal layers, were significantly increased in all treatment groups on 4 and 8 days after the surgery (p < 0.001). At the same times, groups 4 and 3 displayed significantly higher proliferative activities compared to group 2 (p < 0.001). The treatment groups exhibited significantly higher mast cell counts and degranulation phenotypes in comparison with the group 1 on day 4 (p < 0.05). The treatment groups showed significantly lower mast cell counts and degranulation phenotypes than group 1 on day 8 (p < 0.05).The combined and individual application of h-ASC-CM and PBM remarkably could accelerate the proliferation phase of wound healing in the IIDHWM for TIDM in rats, as indicated by improved MRSA control, wound strength, and stereological evaluation. Furthermore, the combination of h-ASC-CM and PBM demonstrated better outcomes compared to the individual application of either h-ASC-CM or PBM alone.

Taxonomic characteristics of &lt;i&gt;Spinacia oleracea&lt;/i&gt; L.

The research focused on the taxonomic study and proximate analysis of Spinacia oleracea L. The samples were fixed in formaldehyde acetic acid alcohol, dehydrated in alcohol solutions of 50%, 70% and 90%, sectioned, stained in 2% of Safranin O, counter stained in Alcian blue for 5 minutes, mounted in glycerine and photo-micrographed using Leica WILD MPS 52 camera on Leitz Draplan microscope. The proximate analysis was done using the Association of Official Analytical Chemists’ methods. The result revealed that spinach is glabrous and reach up to 4 to 8ft in length. The foliar organs are simple, ovate to ovate-triangular and alternate to rosette phyllotaxy. Margins are entire to slightly serrated, reticulate veined, up to 5 ± 4 cm in length and 3 ± 2 cm in width. The basal leaves are far larger than the ones towards the apical meristem. The inflorescence has spikelet of actinomorphic flowers pollinated by wind. The fruit is a berry/ drupe. The foliar epidermal study revealed presence of simple elongated, linear and glandular trichomes, and amphistomatic diacytic stomata. Anatomical study showcased a layer of epidermis, hypodermis of 2 to 3 rolls of collenchyma, general cortex of 7 to 10 rolls of parenchyma and the pith of parenchyma. The node is unilacunar with 2 lateral leaf traces and 1 leaf trace median. The proximate compositions of: 0.19 ± 0.00 Carbohydrate (%); 3.75 ± 0.00 Protein (%); 0.02 ± 0.00 Lipid (%); 94.74 ± 0.36 Moisture (%) content; 0.62 ± 0.32 Fiber (%) and 1.18 ± 0.03 Ash (%). These information would assist for further delimitation of the species.

Fusarium Induced Anatomical and Biochemical Alterations in Wild Type and DPA-treated Wheat Seedlings

Wheat (Triticum aestivum) employs various strategies to defend against Fusarium oxysporum, a soil-borne vascular fungal pathogen that disrupts structural integrity and metabolism. The purpose of this research was to ascertain the alterations of anatomical and biochemical responses in wild-type (WT) and DPA-treated wheat (T. aestivum) seedlings exposed to F. oxysporum. The WT and DPA-treated seedlings showed disorganization of parenchyma cells, sclerenchyma cells, vascular bundles (VBs), and lower numbers of xylem (Xy) and phloem (Ph) cells, and reduced thickness of the cuticle layer (C) at the epidermal layer of shoots. The content of chlorophyll (Chl), carbohydrate, and nucleic acid was reduced in WT and DPA-treated seedlings during infection. Enhanced defense responses through peroxidase (POD), and polyphenol oxidase (PPO) was observed to be high in WT as compared to DPA-treated seedlings under stress condition. In addition, the content of salicylic acid (SA) and phenolics was increased in WT than DPA under stress condition. However, the DPA-treated seedlings showed enhanced growth of fungal mycelia compared to WT during stress condition. Hence, the anatomical and biochemical aspects of DPA-treated seedlings decreased as compared to WT when exposed to F. oxysporum.

A sustainable strategy for generating highly stable human skin equivalents based on fish collagen

Tissue engineered skin equivalents are increasingly recognized as potential alternatives to traditional skin models such as human ex vivo skin or animal skin models. However, most of the currently investigated human skin equivalents (HSEs) are constructed using mammalian collagen which can be expensive and difficult to extract. Fish skin is a waste product produced by fish processing industries and identified as a cost-efficient and sustainable source of type I collagen. In this work, we describe a method for generating highly stable HSEs based on fibrin fortified tilapia fish collagen. The fortified fish collagen (FFC) formulation is optimized to enable reproducible fabrication of full-thickness HSEs that undergo limited contraction, facilitating the incorporation of human donor-derived skin cells and formation of biomimetic dermal and epidermal layers. The morphology and barrier function of the FFC HSEs are compared with a commercial skin model and validated with immunohistochemical staining and transepithelial electrical resistance testing. Finally, the potential of a high throughput screening platform with FFC HSE is explored by scaling down its fabrication to 96-well format.

Hesperetin activates CISD2 to attenuate senescence in human keratinocytes from an older person and rejuvenates naturally aged skin in mice

BackgroundCDGSH iron-sulfur domain-containing protein 2 (CISD2), a pro-longevity gene, mediates healthspan in mammals. CISD2 is down-regulated during aging. Furthermore, a persistently high level of CISD2 promotes longevity and ameliorates an age-related skin phenotype in transgenic mice. Here we translate the genetic evidence into a pharmaceutical application using a potent CISD2 activator, hesperetin, which enhances CISD2 expression in HEK001 human keratinocytes from an older person. We also treated naturally aged mice in order to study the activator’s anti-aging efficacy.MethodsWe studied the biological effects of hesperetin on aging skin using, firstly, a cell-based platform, namely a HEK001 human keratinocyte cell line established from an older person. Secondly, we used a mouse model, namely old mice at 21-month old. In the latter case, we investigate the anti-aging efficacy of hesperetin on ultraviolet B (UVB)-induced photoaging and naturally aged skin. Furthermore, to identify the underlying mechanisms and potential biological pathways involved in this process we carried out transcriptomic analysis. Finally, CISD2 knockdown HEK001 keratinocytes and Cisd2 knockout mice were used to study the Cisd2-dependent effects of hesperetin on skin aging.ResultsFour findings are pinpointed. Firstly, in human skin, CISD2 is mainly expressed in proliferating keratinocytes from the epidermal basal layer and, furthermore, CISD2 is down-regulated in the sun-exposed epidermis. Secondly, in HEK001 human keratinocytes from an older person, hesperetin enhances mitochondrial function and protects against reactive oxygen species-induced oxidative stress via increased CISD2 expression; this enhancement is CISD2-dependent. Additionally, hesperetin alleviates UVB-induced damage and suppresses matrix metalloproteinase-1 expression, the latter being a major indicator of UVB-induced damage in keratinocytes. Thirdly, transcriptomic analysis revealed that hesperetin modulates a panel of differentially expressed genes that are associated with mitochondrial function, redox homeostasis, keratinocyte function, and inflammation in order to attenuate senescence. Intriguingly, hesperetin activates two known longevity-associated regulators, namely FOXO3a and FOXM1, in order to suppress the senescence-associated secretory phenotype. Finally, in mouse skin, hesperetin enhances CISD2 expression to ameliorate UVB-induced photoaging and this occurs via a mechanism involving CISD2. Most strikingly, late-life treatment with hesperetin started at 21-month old and lasting for 5 months, is able to retard skin aging and rejuvenate naturally aged skin in mice.ConclusionsOur results reveal that a pharmacological elevation of CISD2 expression at a late-life stage using hesperetin treatment is a feasible approach to effectively mitigating both intrinsic and extrinsic skin aging and that hesperetin could act as a functional food or as a skincare product for fighting skin aging.

Umbilical therapy for promoting transdermal delivery of topical formulations: Enhanced effect and underlying mechanism

Umbilical paste therapy is a promising method to promote transdermal drug delivery of topical formulations. This work investigated the effect and mechanism of transdermal drug delivery through the umbilical skin. The transdermal permeation studies showed the phenomenon of higher cumulative penetration and faster penetration rates for drug through the umbilical skin compared with non-umbilical skin, namely umbilical pro-permeability. This special transdermal permeability of drugs is influenced by their molecular weight, logP value, ability to form hydrogen bonds, and molecular volume. The underlying mechanism of umbilical pro-permeability was elucidated from unique structure and regulation the effect of drugs on microcirculation in the umbilical skin. Mechanistic studies revealed that this phenomenon was not only associated with the structural and physiological properties of the skin but also to the interactions between drugs and different skin layers. The umbilical pro-permeation is attributed to the thinner stratum corneum layer, differences in stratum corneum lipid composition and keratin structure, and lower levels of intercellular tight junction proteins in the viable epidermis and dermis layer of the skin. Our research indicated that umbilical paste therapy enhanced the transdermal delivery and absorption of drugs by stimulating local blood flow through mast cell activation. Surprisingly, skin temperature modulation and calcitonin gene-related peptide and substance P levels did not appear to significantly affect this process. In conclusion, umbilical drug administration, as a straightforward and non-invasive approach to enhance transdermal drug delivery, presents novel concepts for continued investigation and practical implementation of transdermal drug delivery systems.

Insecticidal activity and possible modes of action of secondary metabolites of some fungal strains and wild plants as natural pesticides against Spodoptera frugiperda

BackgroundThe fall armyworm (FAW), Spodoptera frugiperda, is an invasive and destructive pest to certain strategic crops, especially maize in Egypt. This research was conducted mainly to obtain secondary metabolites from some wild plants and fungal strains, use them in controlling FAW, and investigate their mode of action.ResultsThe ethyl acetate extracts of Cladosporium cladosporioides and Verticillium lecanii, as well as the alkaloid extracts of Ricinus communis and Nicotiana glauca, were extracted to obtain their secondary metabolites. The secondary metabolite contents were identified by gas chromatography mass spectrometry and NMR. The toxicity of all extracts against the 3rd-instar larvae of FAW was evaluated. The possible mode of action of the extracts was studied via their effects on larval enzyme activities and larval tissue. The toxicity results illustrated that, the extract of C. cladosporioides was more effective with LC50 229 ppm, followed by the extract of V. lecanii with LC50 341 ppm and N. glauca with LC50 404 ppm, while the least effective extract was R. communis with LC50 1110 ppm after 72 h of treatment. While, the results of larval enzyme activities showed that C. cladosporioides, V. lecanii, and R. communis extracts led to significant activity of AST, ALT, ACP, and ALP enzymes, but GST and AchE were inhibited in treated larvae compared with control. While N. glauca alkaloid extract caused significant inhibition of AST, ALT, ACP, AchE, and GST enzymes, ALP was activated in the treated larvae compared with control. The results of larval tissue slides indicated that the most affected tissues were the cuticle layer and the membrane lining of the midgut, in addition to the fatty bodies.ConclusionThus, natural pesticides would have a promising role in terms of controlling the FAW and according to this study, it was recommended that, alkaloid extracts of tested wild plants and ethyl acetate extracts of fungal strains be used as natural pesticides to control the fall armyworm, S. frugiperda.

Low-velocity impact response of a novel bionic turtle shell back armor sandwich structure

Turtle shell dorsal armor comprises a typical lightweight laminated composite structural material, which is constructed by cuticle and bone layer, with high specific strength and high fracture toughness. The red-eared slider turtle, a widely studied species of turtle, has a rich hierarchical structure. In this paper, according to the structure of red-eared slider turtle shell dorsal armor and the characteristics of each layer as well as by taking into full consideration of the fine structure of cuticle and ventral cortex of the shell dorsal armor, two bionic foam silicone rubber sandwich structures of different levels were prepared. Low-velocity impact test and finite element simulation analysis were carried out to study the mechanical response, specific absorbed energy, and damage mode of the two bionic sandwich structures under different impact energies, hammerhead shapes, and hammerhead radii. By comparing the mechanical response and specific energy absorption with the existing ordinary sandwich structure, we find that the two sandwich structures modeled in this paper exhibit better impact resistance than the ordinary sandwich structure. The shape and radius of the hammer head have a significant effect on the energy absorption characteristics of the sandwich structure, and the damage mode under the hemispherical hammer head is mainly dominated by tensile tearing damage, while the damage mode of extrusion fracture is more obvious under the impact of the conical hammer head. With the increase of the radius of the hammer head, the absorbed energy and specific energy absorption of the sandwich structure increases.

Microstructure and Mechanical Characterization of Rice Husks from the Tolima Region of Colombia

The under-utilization of rice husk, a milling by-product, demands attention due to its widespread disposal and limited usage. This research aims to assess the physical properties and mechanical behavior of three rice husk varieties (F 2000, Orizyca, and Panorama 394), to determine their strength capacities and potential applications. Mechanical properties are evaluated through a non-standardized tension test using a universal machine. Subsequent analyses include measuring the moisture content following ASTM D1348, determining the particle size distribution through ASAE Standard S319, and establishing the bulk density using ASAE Standard S269 Method 4. Mechanical resistance in the rice husk varieties ranged from 60 MPa to 130 MPa, with a particle density exceeding 300 kg/m3 and an average apparent density of 140 kg/m3. Scanning electron microscopy revealed the husk structures, identifying epidermis, hypodermis, and sub-hypodermis layers. The mechanical stress of the Orizyca variety was 1.89 times higher than that of F 2000, and 1.18 times higher than that of Panorama 394. Potential applications include brick manufacturing and thermoformed materials for Orizyca and Panorama 394, while F 2000 could be utilized for producing fuel briquettes or cardboard, among other possibilities.

Stem anatomy of some Crepis L. (Asteraceae) taxa and its taxonomic significance

In this study, the stem anatomy of nine Crepis (Asteraceae) taxa were decribed for the first time from Türkiye. The anatomical data obtained were evaluated in terms of taxonomy with analysis of variance and principal components analysis. The stem mainly consist of one layer epidermis, parenchymatous cortex, collateral vascular bundles and parenchymatous pith in all taxa examined. Glandular or non-glandular trichomes are found in the epidermal cells of the stem in some species examined. Despite that fact that all taxa examined have similar stem anatomy, quantitative traits such as length or width of the anatomical characters significantly varry among the taxa. In particular, the xylem thickness considerably differs among the taxa studied, according to the results of analysis of variance. Besides, the xylem is more thicker in caulescent species than scapigerous taxa. According to the results of principal components analysis, the xylem thickness and the epidermis cell length explain most of the total variation with about 82% value among the studied taxa. These results show that xylem thickness and epidermis cell length have a high taxonomic value.

DERMATITIS ARTEFACTA WITH Proteus mirabilis INFECTION IN COINCIDENCE WITH PYODERMA GANGRENOSUM IN SCHIZOPHRENIC PATIENT

Dermatitis artefacta (DA) is a psychiatric disorder with secondary manifestations on the skin. One of the most common skin lesions in DA is chronic ulcer which also can be caused by pyoderma gangrenosum (PG). There are some bacteria found in chronic ulcer such as Proteus mirabilis. A forty-one years old female with chronic wounds on her chest and left leg. Based on history taking of present illness, physical examinations, laboratory tests and histopathology of the skin lesions, the patient was diagnosed with DA and PG. She was also diagnosed with schizophrenia catatonic type. Chest x-ray showed pneumonia while the swab culture showed growth of Proteus mirbabilis. She was given an oral cefadroxile 500 mg three times daily, cetirizine 10 mg once daily, wound dressing and gentamycin ointment twice daily. She also received oral risperidone 0.5 mg twice daily combined with behavioral therapy from Psychiatric Outpatientclinic. Dermatitis artefacta is a psychocutaneous disorder with uncommon morphology. The most common psychological condition related to DA is schicophrenia. There are some specific histopathology features of DA such as dominant destruction of epidermal layer, multinucleated epidermal keratinocytes or destruction of keratinocytes. Chronic ulcers in DA might be mimicking with PG, which is a chronic recidive neutrophilic dermatoses. Proteus mirabilis is one of the most common causes of urinary tract infection, meanwhile it can also cause chronic ulcers and respiratory tract infection as pneumonia.

Development-Associated Genes of the Epidermal Differentiation Complex (EDC).

The epidermal differentiation complex (EDC) is a cluster of genes that encode protein components of the outermost layers of the epidermis in mammals, reptiles and birds. The development of the stratified epidermis from a single-layered ectoderm involves an embryo-specific superficial cell layer, the periderm. An additional layer, the subperiderm, develops in crocodilians and over scutate scales of birds. Here, we review the expression of EDC genes during embryonic development. Several EDC genes are expressed predominantly or exclusively in embryo-specific cell layers, whereas others are confined to the epidermal layers that are maintained in postnatal skin. The S100 fused-type proteins scaffoldin and trichohyalin are expressed in the avian and mammalian periderm, respectively. Scaffoldin forms the so-called periderm granules, which are histological markers of the periderm in birds. Epidermal differentiation cysteine-rich protein (EDCRP) and epidermal differentiation protein containing DPCC motifs (EDDM) are expressed in the avian subperiderm where they are supposed to undergo cross-linking via disulfide bonds. Furthermore, a histidine-rich epidermal differentiation protein and feather-type corneous beta-proteins, also known as beta-keratins, are expressed in the subperiderm. The accumulating evidence for roles of EDC genes in the development of the epidermis has implications on the evolutionary diversification of the skin in amniotes.

A COMPARATIVE CLINICAL STUDY TO EVALUATE THE EFFICACY OF JEERAKADI LEPA AND MUKHAKANTIKARA LEPA IN THE MANAGEMENT OF VYANGA(MELASMA)

Vyanga is one of the important diseases pertaining to hyper Pigmentation disorders. It is considered Kshudraro-gas, which occurs mainly due to vitiation of Vata, Pitta and Rakta. Vyanga presence of Neeruja, Tanu, Shyavav-arnayukta mandala on Mukhapradesha. Melasma is a hyperpigmented macular lesion that develops slowly and symmetrically over the malar area, bridge of the nose, forehead and upper lips, more commonly seen in females than males. Hyperpigmentation is due to increased melanocytes activity in epidermal and dermal layers. Brhajaka pitta is mainly related to Varna of twacha. So, Pitta is the main culprit to cause Vyanga. Here, all Jeerakadi Lepa's and Mukhakantikara Lepa's ingredients are Pittashamaka, Varnyakara, Raktaprasadaka, Twakprasadaka, Kandughna, Kusthaghna. Methods: A Randomized comparative clinical trial is adopted. In Group A were given Jeerakadi lepa with milk for 30 days application (once in a day).In Group B were given Mukhakantikara lepa with water for 30 days application (once in a day) .Total duration of study was carried out for 45 days. Results: By applying the Friedman test and Wilcoxon sign rank test for within the group it was sta-tistically significant. The Mann Whitney U test is applied between the groups the results showed statistically not significant. Hence, we conclude that we reject null hypothesis H0 and accept the alternate hypothesis H2. i.e H2 : Jeerakadi lepa is more effective than Mukhakantikara lepa in the management of Vyanga.

A modified model to assess the thermal protective performance of fire-retardant clothing exposed to both flame and radiant source

The present work evaluates the thermal protective performance (TPP) of a multi-layered fire-resistant fabric system subjected to a high intensity risky thermal environment integrating both flame and radiant heat exposure by developing a modified model for the fabric as well as the skin. The present numerical analysis takes into consideration a multiple-layer flameproof gear (outer shell, moisture barrier, and thermal liner), an airgap separating fabric and skin, and a three-layer of skin (epidermis, dermis, and fat layer). The present model is formulated by considering a two-flux model for the radiative heat interaction in the porous fabric medium and a nonlinear bioheat transfer model for the multi-layered skin. The radiative part of the total incident energy from the flame and the radiant heater is considered to be absorbed, emitted, reflected, and transmitted through the porous fibrous layer. Here, a two-flux model is implemented to simulate the self-emission of hot gas trapped inside the porous fabrics. The thermal response in multi-layered skin is analysed using a non-linear bioheat transfer model considering a temperature dependent thermal conductivity of the living tissue. Purely radiant exposure markedly impairs turnout gear protection, while performance deteriorates more gradually with increased convective thermal energy. Greater fabric transmissivity negatively affects skin temperature distribution and TPP ratings more than equivalent reflection reduction. These study results aid in enhancing flame-resistant fabric thermal protection.

Use of Integra® on avascular tissue

Integra® (Integra LifeSciences) is a well-known dermal regeneration template used in partial and full-thickness wound reconstruction. It can be applied directly on to vascular tissue to create a bed for a skin graft, which is often placed in a second surgery. We present our experience of its novel use in oral and maxillofacial surgery patients, using it directly on bone and cartilage (avascular tissue) without further skin grafting. Patients who required full-thickness excision of lesions down to bone or cartilage and who were treated using Integra® were included. After scalp or ear lesion resection, the collagenous dermal layer of Integra® was placed directly on to bone or cartilage and, along with its outer silicone epidermal layer, secured to the defect with absorbable sutures and a bolster dressing. The wounds were kept dry for 14 days, at which point the dressing and silicone were removed and patients continued regular wound care. Seventeen patients were included, 15 of whom had squamous cell carcinoma. One was lost to follow up. The rest achieved complete healing of the defect. Histology showed epidermis developing on the Integra® surface and at one year, the appearance of normal scarred skin. This novel approach could redefine the uses of Integra®, avoiding the need for free-flap surgery or skin grafting when reconstructing large defects. Further resection of close margins or recurrence is easier after reconstruction using dermal regeneration material than after reconstruction with a local or free flap.

Turing Pattern Formation in Reaction-Cross-Diffusion Systems with a Bilayer Geometry

Conditions for self-organisation via Turing’s mechanism in biological systems represented by reaction-diffusion or reaction-cross-diffusion models have been extensively studied. Nonetheless, the impact of tissue stratification in such systems is under-explored, despite its ubiquity in the context of a thin epithelium overlying connective tissue, for instance the epidermis and underlying dermal mesenchyme of embryonic skin. In particular, each layer can be subject to extensively different biochemical reactions and transport processes, with chemotaxis - a special case of cross-diffusion - often present in the mesenchyme, contrasting the solely molecular transport typically found in the epidermal layer. We study Turing patterning conditions for a class of reaction-cross-diffusion systems in bilayered regions, with a thin upper layer and coupled by a linear transport law. In particular, the role of differential transport through the interface is explored together with the presence of asymmetry between the homogeneous equilibria of the two layers. A linear stability analysis is carried out around a spatially homogeneous equilibrium state in the asymptotic limit of weak and strong coupling strengths, where quantitative approximations of the bifurcation curve can be computed. Our theoretical findings, for an arbitrary number of reacting species, reveal quantitative Turing conditions, highlighting when the coupling mechanism between the layered regions can either trigger patterning or stabilize a spatially homogeneous equilibrium regardless of the independent patterning state of each layer. We support our theoretical results through direct numerical simulations, and provide an open source code to explore such systems further.