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1.
Immunity ; 56(7): 1561-1577.e9, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37402364

RESUMO

Hypodermis is the predominant site of Staphylococcus aureus infections that cause cellulitis. Given the importance of macrophages in tissue remodeling, we examined the hypodermal macrophages (HDMs) and their impact on host susceptibility to infection. Bulk and single-cell transcriptomics uncovered HDM subsets with CCR2-dichotomy. HDM homeostasis required the fibroblast-derived growth factor CSF1, ablation of which abrogated HDMs from the hypodermal adventitia. Loss of CCR2- HDMs resulted in accumulation of the extracellular matrix component, hyaluronic acid (HA). HDM-mediated HA clearance required sensing by the HA receptor, LYVE-1. Cell-autonomous IGF1 was required for accessibility of AP-1 transcription factor motifs that controlled LYVE-1 expression. Remarkably, loss of HDMs or IGF1 limited Staphylococcus aureus expansion via HA and conferred protection against cellulitis. Our findings reveal a function for macrophages in the regulation of HA with an impact on infection outcomes, which may be harnessed to limit the establishment of infection in the hypodermal niche.


Assuntos
Infecções Estafilocócicas , Staphylococcus aureus , Humanos , Staphylococcus aureus/fisiologia , Celulite (Flegmão)/metabolismo , Macrófagos/metabolismo , Matriz Extracelular
2.
Ann Bot ; 133(7): 931-940, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38448365

RESUMO

BACKGROUND AND AIMS: Internal root aeration is essential for root growth in waterlogged conditions. Aerenchyma provides a path for oxygen to diffuse to the roots. In most wetland species, including rice, a barrier to radial oxygen loss (ROL) allows more of the oxygen to diffuse to the root tip, enabling root growth into anoxic soil. Most dryland crops, including barley, do not form a root ROL barrier. We previously found that abscisic acid (ABA) signalling is involved in the induction of ROL barrier formation in rice during waterlogging. Although rice typically does not form a tight ROL barrier in roots in aerated conditions, an ROL barrier with suberized exodermis was induced by application of exogenous ABA. Therefore, we hypothesized that ABA application could also trigger root ROL barrier formation with hypodermal suberization in barley. METHODS: Formation of an ROL barrier was examined in roots in different exogenous ABA concentrations and at different time points using cylindrical electrodes and Methylene Blue staining. Additionally, we evaluated root porosity and observed suberin and lignin modification. Suberin, lignin and Casparian strips in the cell walls were observed by histochemical staining. We also evaluated the permeability of the apoplast to a tracer. KEY RESULTS: Application of ABA induced suberization and ROL barrier formation in the adventitious roots of barley. The hypodermis also formed lignin-containing Casparian strips and a barrier to the infiltration of an apoplastic tracer (periodic acid). However, ABA application did not affect root porosity. CONCLUSIONS: Our results show that in artificial conditions, barley can induce the formation of ROL and apoplastic barriers in the outer part of roots if ABA is applied exogenously. The difference in ROL barrier inducibility between barley (an upland species) and rice (a wetland species) might be attributable to differences in ABA signalling in roots in response to waterlogging conditions.


Assuntos
Ácido Abscísico , Hordeum , Lignina , Oxigênio , Raízes de Plantas , Hordeum/efeitos dos fármacos , Hordeum/metabolismo , Hordeum/crescimento & desenvolvimento , Ácido Abscísico/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Oxigênio/metabolismo , Lignina/metabolismo , Parede Celular/metabolismo , Parede Celular/efeitos dos fármacos , Reguladores de Crescimento de Plantas/metabolismo , Lipídeos
3.
Adv Exp Med Biol ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38980552

RESUMO

Advancements in tissue engineering enable the fabrication of complex and functional tissues or organs. In particular, bioprinting enables controlled and accurate deposition of cells, biomaterials, and growth factors to create complex 3D skin constructs specific to a particular individual. Despite these advancements, challenges such as vascularization, long-term stability, and regulatory considerations hinder the clinical translation of bioprinted skin constructs. This chapter focuses on such approaches using advanced biomaterials and bioprinting techniques to overcome the current barriers in wound-healing studies. Moreover, it addresses current obstacles in wound-healing studies, highlighting the need for continued research and innovation to overcome these barriers and facilitate the practical utilization of bioprinted skin constructs in clinical settings.

4.
Clin Anat ; 36(4): 570-580, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36576229

RESUMO

The aim of this study was to examine data demonstrating that Scarpa's fascia, a superficial fascia of the anterior abdominal wall, is a vascularized tissue. Specimens of the fascia of seven volunteers undergoing abdominoplasty surgical procedures at the Plastic Surgery Unit of the University of Padova Medical Center were collected. Fractal analysis and quantitative assessment of the vascular network of the fascia was carried out, exploiting the presence of blood in the vessels. Each sample was divided and processed for histological/immunohistochemical analysis (into 5 micron-paraffin embedded sections and cryo-sectioned free-floating samples) as well as for electron microscopy study. A rich vascular pattern forming a fine, dense meshwork with an area percentage of 6.20% ± 2.10% von Willebrand factor stained vessels was noted in all the specimens of the fascia examined; the area percentage of the αSMA-stained vessels was 2.93% ± 1.80%. The diameters of the vessels fell between the 13 and 65 µm range; the network was composed of arteries, veins, capillaries and lymphatic segments. Topological results showed that the vascular network within Scarpa's fascia is well branched (segments: 6615 ± 3070 and 8.40 ± 3.40 per mm2 ; crossing points: 3092 ± 1490 and 3.40 ± 1.90 per mm2 ). Fractal analysis (fractal dimension = 1.063 ± 0.10; lacunarity = 0.60 ± 0.10) revealed that this particular vascular network has an optimal spatial distribution and homogeneity occupying the entire space of the superficial fascia. These findings could undoubtedly be useful to plastic surgeons as well as to pain management specialists.


Assuntos
Parede Abdominal , Abdominoplastia , Vasos Linfáticos , Humanos , Tela Subcutânea/cirurgia , Fáscia , Parede Abdominal/cirurgia , Abdominoplastia/métodos
5.
Sensors (Basel) ; 22(17)2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-36080817

RESUMO

The presented study discusses the possible disturbing effects of the electromagnetic field of antennas used in mobile phones or WiFi technologies on the pacemaker in the patient's body. This study aims to obtain information on how the thickness of skin layers (such as the thickness of the hypodermis) can affect the activity of a pacemaker exposed to a high-frequency electromagnetic field. This study describes the computational mathematical analysis and modeling of the heart pacemaker inserted under the skin exposed to various electromagnetic field sources, such as a PIFA antenna and a tuned dipole antenna. The finite integration technique (FIT) for a pacemaker model was implemented within the commercially available CST Microwave simulation software studio. Likewise, the equations that describe the mathematical relationship between the subcutaneous layer thickness and electric field according to different exposures of a tuned dipole and a PIFA antenna are used and applied for training a neural network. The main output of this study is the creation of a mathematical model and a multilayer feedforward neural network, which can show the dependence of the thickness of the hypodermis on the size of the electromagnetic field, from the simulated data from CST Studio.


Assuntos
Telefone Celular , Marca-Passo Artificial , Simulação por Computador , Campos Eletromagnéticos , Humanos , Redes Neurais de Computação
6.
Rheumatology (Oxford) ; 59(7): 1671-1678, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31665474

RESUMO

OBJECTIVE: High frequency ultrasound allows visualization of epidermis, dermis and hypodermis, precise measurement of skin thickness, as well as assessment of skin oedema, fibrosis and atrophy. The aim of this pilot cross-sectional observational study was to assess the performance and multiobserver variability of ultra-high-frequency (UHF) (50 MHz) ultrasound (US) in measuring skin thickness as well as the capacity of UHF-derived skin features to differentiate SSc patients from healthy controls. METHODS: Twenty-one SSc patients (16 limited and five diffuse SSc) and six healthy controls were enrolled. All subjects underwent US evaluation by three experts at three anatomical sites (forearm, hand and finger). Dermal thickness was measured and two rectangular regions of interest, one in dermis and one in hypodermis, were established for texture feature analysis. RESULTS: UHF-US allowed a precise identification and measurement of the thickness of the dermis. The dermal thickness in the finger was significantly higher in patients than in controls (P < 0.05), while in the forearm it was significantly lower in patients than in controls (P < 0.001). Interobserver variability for dermal thickness was good to excellent [forearm intraclass correlation coefficient (ICC) = 0.754; finger ICC = 0.699; hand ICC = 0.602]. Texture computed analysis of dermis and hypodermis was able to discriminate between SSc and healthy subjects (area under the curve >0.7). CONCLUSION: These preliminary data show that skin UHF-US allows a very detailed imaging of skin layers, a reliable measurement of dermal thickness, and a discriminative capacity between dermis and hypodermis texture features in SSc and healthy subjects.


Assuntos
Antebraço/diagnóstico por imagem , Mãos/diagnóstico por imagem , Escleroderma Sistêmico/diagnóstico por imagem , Pele/diagnóstico por imagem , Ultrassonografia , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Adulto Jovem
7.
Molecules ; 25(20)2020 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-33050647

RESUMO

Calcium is one of the most poorly reutilized nutrients. Its deficiencies cause various physiological disturbances and, consequently, reduce the quantity and quality of yields. Reduced content of Ca2+ ions in cells leads to development of, e.g., bitter pit in apples. Efficient and instantaneous mitigation of Ca2+ deficiencies is provided by foliar feeding. There are no detailed data on the effect of foliar feeding with various calcium forms on the cell structure or on the microanalysis and mapping of this element in apple fruit cells. Therefore, we carried out comparative studies of the ultrastructure of epidermis and hypodermis cells, to assess the content and distribution of calcium in the cell wall, cytoplasmic membrane, cytoplasm, and precipitates of Malus domestica Borkh. 'Szampion' fruit exposed to four Ca treatments, including the control with no additional Ca supplementation (I) and foliar applications of Ca(NO3)2 (II), CaCl2 (III), and Ca chelated with EDTA (IV). Light and transmission electron microscopy and an X-ray microanalyzer were used and showed a beneficial effect of calcium preparations on the ultrastructure of fruit epidermis and hypodermis cells, manifested in the presence of a normally developed cell wall with a regular middle lamella, preserved continuity of cytoplasmic membranes, and stabilized cell structure. In the selected elements of apical epidermis cells, the highest level of Ca2+ ions was detected in the middle lamella, cell wall, plasmalemma, and cytoplasm. The highest increase in the Ca2+ content in these cell constituents was recorded in treatment IV, whereas the lowest value of the parameters was noted in variant III.


Assuntos
Parede Celular/metabolismo , Malus/metabolismo , Cálcio/metabolismo , Citoplasma/metabolismo , Microscopia Eletrônica de Transmissão
8.
J Anat ; 235(6): 1065-1077, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31402460

RESUMO

Fascia in the veterinary sciences is drawing attention, such that physiotherapists and animal practitioners are now applying techniques based on the concept of fascia studies in humans. A comprehensive study of fascia is therefore needed in animals to understand the arrangement of the fascial layers in an unguligrade horse and a digitigrade dog. This study has examined the difference between the horse and the dog fascia at specific regions, in terms of histology, and has compared it with the human model. Histological examinations show that in general the fascia tissue of the horse exhibits a tight and dense composition, while in the dog it is looser and has non-dense structure. Indeed, equine fascia appears to be different from both canine fascia and the human fascia model, whilst canine fascia is very comparable to the human model. Although regional variations were observed, the superficial fascia (fascia superficialis) in the horse was found to be trilaminar in the trunk, yet multilayered in the dog. Moreover, crimping of collagen fibers was more visible in the horse than the dog. Blood vessels and nerves were present in the loose areolar tissue of the superficial and the profound compartment of hypodermis. The deep fascia (fascia profunda) in the horse was thick and tightly attached to the underlying muscle, while in the dog the deep fascia was thin and loosely attached to underlying structures. Superficial and deep fascia fused in the extremities. In conclusion, gross dissection and histology have revealed species variations that are related to the absence or presence of the superficial adipose tissue, the retinacula cutis superficialis, the localization and amount of elastic fibers, as well as the ability to slide and glide between the different layers. Further research is now needed to understand in more detail whether these differences have an influence on the biomechanics, movements and proprioception of these animals.


Assuntos
Cães/anatomia & histologia , Fáscia/anatomia & histologia , Cavalos/anatomia & histologia , Animais , Tecido Conjuntivo/anatomia & histologia , Sistema Musculoesquelético/anatomia & histologia , Tela Subcutânea/anatomia & histologia
9.
J Exp Bot ; 70(21): 6085-6099, 2019 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-31408160

RESUMO

In apple (Malus×domestica) fruit, the different layers of the exocarp (cuticle, epidermis, and hypodermis) protect and maintain fruit integrity, and resist the turgor-driven expansion of the underlying thin-walled cortical cells during growth. Using in situ immunolocalization and size exclusion epitope detection chromatography, distinct cell type differences in cell wall composition in the exocarp were revealed during apple fruit development. Epidermal cell walls lacked pectic (1→4)-ß-d-galactan (associated with rigidity), whereas linear (1→5)-α-l-arabinan (associated with flexibility) was exclusively present in the epidermal cell walls in expanding fruit and then appeared in all cell types during ripening. Branched (1→5)-α-l-arabinan was uniformly distributed between cell types. Laser capture microdissection and RNA sequencing (RNA-seq) were used to explore transcriptomic differences controlling cell type-specific wall modification. The RNA-seq data indicate that the control of cell wall composition is achieved through cell-specific gene expression of hydrolases. In epidermal cells, this results in the degradation of galactan side chains by possibly five ß-galactosidases (BGAL2, BGAL7, BGAL10, BGAL11, and BGAL103) and debranching of arabinans by α-arabinofuranosidases AF1 and AF2. Together, these results demonstrate that flexibility and rigidity of the different cell layers in apple fruit during development and ripening are determined, at least in part, by the control of cell wall pectin remodelling.


Assuntos
Parede Celular/metabolismo , Frutas/genética , Regulação da Expressão Gênica de Plantas , Malus/genética , Pectinas/metabolismo , Parede Celular/química , Parede Celular/genética , Epitopos/metabolismo , Frutas/crescimento & desenvolvimento , Galactanos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Malus/crescimento & desenvolvimento , Peso Molecular , Epiderme Vegetal/metabolismo , Polissacarídeos/metabolismo , Solubilidade , Transcriptoma/genética
10.
Biochem J ; 473(11): 1507-21, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-27009306

RESUMO

L-Rhamnose is a common component of cell-wall polysaccharides, glycoproteins and some natural products in bacteria and plants, but is rare in fungi and animals. In the present study, we identify and characterize a biosynthetic pathway for dTDP-rhamnose in Caenorhabditis elegans that is highly conserved across nematode species. We show that RML-1 activates glucose 1-phosphate (Glc-1-P) in the presence of either dTTP or UTP to yield dTDP-glucose or UDP-glucose, respectively. RML-2 is a dTDP-glucose 4,6-dehydratase, converting dTDP-glucose into dTDP-4-keto-6-deoxyglucose. Using mass spectrometry and NMR spectroscopy, we demonstrate that coincubation of dTDP-4-keto-6-deoxyglucose with RML-3 (3,5-epimerase) and RML-4 (4-keto-reductase) produces dTDP-rhamnose. RML-4 could only be expressed and purified in an active form through co-expression with a co-regulated protein, RML-5, which forms a complex with RML-4. Analysis of the sugar nucleotide pool in C. elegans established the presence of dTDP-rhamnose in vivo Targeting the expression of the rhamnose biosynthetic genes by RNAi resulted in significant reductions in dTDP-rhamnose, but had no effect on the biosynthesis of a closely related sugar, ascarylose, found in the ascaroside pheromones. Therefore, the rhamnose and ascarylose biosynthetic pathways are distinct. We also show that transcriptional reporters for the rhamnose biosynthetic genes are expressed highly in the embryo, in the hypodermis during molting cycles and in the hypodermal seam cells specifically before the molt to the stress-resistant dauer larval stage. These expression patterns suggest that rhamnose biosynthesis may play an important role in hypodermal development or the production of the cuticle or surface coat during molting.


Assuntos
Caenorhabditis elegans/metabolismo , Muda/fisiologia , Ramnose/metabolismo , Nucleotídeos de Timina/metabolismo , Animais , Vias Biossintéticas/fisiologia , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Cromatografia Líquida de Alta Pressão , Desoxiglucose/análogos & derivados , Desoxiglucose/metabolismo , Glucose/análogos & derivados , Glucose/metabolismo , Glucose-1-Fosfato Adenililtransferase/genética , Glucose-1-Fosfato Adenililtransferase/metabolismo , Cinética , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Muda/genética , Filogenia , Interferência de RNA , Uridina Difosfato Glucose/metabolismo
11.
Dev Biol ; 401(2): 276-86, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25732775

RESUMO

The heterochronic pathway controls temporal patterning during Caenorhabditis elegans larval development. The highly conserved let-7 microRNA (miRNA) plays a key role in this pathway, directing the larval-to-adult (L/A) transition. Hence, knowledge of the genetic interactome of let-7 has the potential to provide insight into both control of temporal cell fates and mechanisms of regulation and function of miRNAs. Here, we report the results of a genome-wide, RNAi-based screen for suppressors of let-7 mutant vulval bursting. The 201 genetic interaction partners of let-7 thus identified include genes that promote target silencing activity of let-7, seam cell differentiation, or both. We illustrate the suitability of our approach by uncovering the mitotic cyclin-dependent kinase CDK-1 as a downstream effector of let-7 that affects both seam cell proliferation and differentiation, and by identifying a core set of candidate modulators of let-7 activity, which includes all subunits of the condensin II complex. We propose that the genes identified in our screen thus constitute a valuable resource for studies of the heterochronic pathway and miRNAs.


Assuntos
Padronização Corporal/genética , Proteína Quinase CDC2/genética , Caenorhabditis elegans/embriologia , MicroRNAs/genética , Adenosina Trifosfatases/genética , Animais , Proteína Quinase CDC2/biossíntese , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Diferenciação Celular/genética , Proteínas de Ligação a DNA/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Complexos Multiproteicos/genética , Interferência de RNA , Fatores de Transcrição/genética
12.
Exp Parasitol ; 167: 94-102, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27240755

RESUMO

A gene encoding fatty acid- and retinoid-binding protein was isolated from the cereal cyst nematode Heterodera avenae and the biochemical function of the protein that it encodes was analysed. The full-length cDNA of the Ha-far-1 gene is 827 bp long and includes a 22- nucleotide trans-spliced leader sequence (SL1) at its 5-end. The genomic clone of Ha-far-1 consists of eight exons separated by seven introns, which range in size from 48 to 186 bp. The Ha-far-1 cDNA contains an open reading frame encoding a 191 amino acid protein, with a predicted secretory signal peptide. Sequence analysis showed that Ha-FAR-1 has highest similarity to the Gp-FAR-1 protein from the potato cyst nematode, Globodera pallida and that the protein was grouped with all homologues from other plant-parasitic nematodes in a phylogenetic analysis. Fluorescence-based ligand binding analysis confirmed that the recombinant Ha-FAR-1 protein was able to bind fatty acids and retinol. Spatial and temporal expression assays showed that the transcripts of Ha-far-1 accumulated mainly in the hypodermis and that the gene is most highly expressed in third-stage juveniles of H. avenae. Fluorescence immunolocalization showed that the Ha-FAR-1 protein was present on the surface of the infective second-stage juveniles of H. avenae. Nematodes treated with dsRNA corresponding to Ha-far-1 showed significantly reduced reproduction compared to nematodes exposed to dsRNA from a non-endogenous gene, suggesting that Ha-far-1 may be an effective target gene for control of H. avenae using an RNAi strategy.


Assuntos
Proteínas de Ligação a Ácido Graxo/isolamento & purificação , Proteínas de Helminto/isolamento & purificação , Proteínas de Ligação ao Retinol/isolamento & purificação , Tylenchoidea/química , Sequência de Aminoácidos , Animais , Sequência de Bases , Western Blotting , Clonagem Molecular , DNA Complementar/química , DNA de Helmintos/isolamento & purificação , Proteínas de Ligação a Ácido Graxo/química , Proteínas de Ligação a Ácido Graxo/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Inativação Gênica , Proteínas de Helminto/química , Proteínas de Helminto/genética , Hibridização In Situ , Ligantes , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas de Ligação ao Retinol/química , Proteínas de Ligação ao Retinol/genética , Alinhamento de Sequência , Transcrição Gênica , Triticum/parasitologia , Tylenchoidea/genética
13.
Genesis ; 53(3-4): 278-84, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25711168

RESUMO

The cuticle of the nematode Caenorhabditis elegans is a specialized extracellular matrix whose major component is collagen. Cuticle collagens are encoded by a large multigene family consisting of more than 150 members. Cuticle collagen genes are expressed in epidermis (hypodermis) and may be stage-specific or cyclically expressed. We identified cuticle collagen genes as transcriptional targets of the DBL-1 TGF-ß-related signaling pathway. These studies prompted us to investigate the cis-regulatory sequences required for transcription of one of the target genes, col-41. We generated reporter constructs that reproduce stage- and tissue-specific expression of fluorescent markers. We identify four conserved sequence elements that are required for transcription of reporters. Finally, we provide evidence that col-41 expression is controlled by a sequence element containing two GATA sites and by the epidermal GATA transcription factors ELT-1 and ELT-3.


Assuntos
Animais Geneticamente Modificados/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Colágeno/genética , Fatores de Transcrição GATA/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Elementos Reguladores de Transcrição/genética , Animais , Animais Geneticamente Modificados/genética , Animais Geneticamente Modificados/crescimento & desenvolvimento , Sequência de Bases , Caenorhabditis elegans/genética , Caenorhabditis elegans/crescimento & desenvolvimento , Proteínas de Caenorhabditis elegans/genética , Colágeno/metabolismo , Fatores de Transcrição GATA/genética , Dados de Sequência Molecular , Regiões Promotoras Genéticas/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência do Ácido Nucleico , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo
14.
Lasers Surg Med ; 47(2): 183-95, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25651998

RESUMO

BACKGROUND AND OBJECTIVE: Radiofrequency currents are commonly used in dermatology to treat cutaneous and subcutaneous tissues by heating. The subcutaneous morphology of tissue consists of a fine, collagenous and fibrous septa network enveloping clusters of adipocyte cells. The architecture of this network, namely density and orientation of septa, varies among patients and, furthermore, it correlates with cellulite grading. In this work we study the effect of two clinically relevant fibrous septa architectures on the thermal and elastic response of subcutaneous tissue to the same RF treatment; in particular, we evaluate the thermal damage and thermal stress induced to an intermediate- and a high-density fibrous septa network architecture that correspond to clinical morphologies of 2.5 and 0 cellulite grading, respectively. STUDY DESIGN/MATERIALS AND METHODS: We used the finite element method to assess the electric, thermal and elastic response of a two-dimensional model of skin, subcutaneous tissue and muscle subjected to a relatively long, constant, low-power RF treatment. The subcutaneous tissue is constituted by an interconnected architecture of fibrous septa and fat lobules obtained by processing micro-MRI sagittal images of hypodermis. As comparison criteria for the RF treatment of the two septa architectures, we calculated the accumulated thermal damage that corresponds to 63% loss in cell viability. RESULTS: Electric currents preferentially circulated through the fibrous septa in the subcutaneous tissue. However, the intensity of the electric field was higher within the fat because it is a poor electric conductor. The power absorption in the fibrous septa relative to that in the fat varied with septum orientation: it was higher in septa with vertical orientation and lower in septa with horizontal orientation. Overall, maximum values of electric field intensity, power absorption and temperature were similar for both fibrous septa architectures. However, the high-density septa architecture (cellulite grade 0) had a more uniform and broader spatial distribution of power absorption, resulting in a larger cross-sectional area of thermal damage (≈1.5 times more). Volumetric strains (expansion and contraction) were small and similar for both network architectures. During the first seconds of RF exposure, the fibrous septa were subjected to thermal expansion regardless of orientation. In the long term, the fibrous septa contracted due to the thermal expansion of fat. Skin and muscle were subjected to significantly higher Von Mises stresses (measure of yield) or distortion energy than the subcutaneous tissue. CONCLUSION: The distribution of electric currents within subcutaneous tissues depends on tissue morphology. The electric field is more intense in septum oriented along the skin to muscle (top to bottom) direction, creating lines or planes of preferential heating. It follows that the more septum available for preferential heating, the larger the extent of volumetric RF-heating and thermal damage to the subcutaneous tissue. Thermal load alone, imposed by long-exposure to heating up to 50 °C, results in small volumetric expansion and contraction in the subcutaneous tissue. The subcutaneous tissue is significantly less prone to non-reversible deformation by a thermal load than the skin and muscle.


Assuntos
Tecido Adiposo/efeitos da radiação , Músculos/efeitos da radiação , Ondas de Rádio , Pele/efeitos da radiação , Tela Subcutânea/efeitos da radiação , Elasticidade/efeitos da radiação , Análise de Elementos Finitos , Humanos , Modelos Biológicos , Condutividade Térmica
15.
J Exp Biol ; 217(Pt 23): 4119-22, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25278475

RESUMO

Although Caenorhabditis elegans is commonly used as a model organism for studies of cell biology, development and physiology, the small size of the worm has impeded measurements of ion transport by the excretory cell and hypodermis. Here, we use the scanning ion-selective microelectrode technique to measure efflux and influx of K(+), H(+), Na(+) and Ca(2+) in intact worms. Transport of ions into, or out of, immobilized worms produces small gradients in ion concentration in the unstirred layer near the surface of the worm. These gradients are readily detectable with ion-selective microelectrodes and the corresponding ion fluxes can be estimated using the Fick equation. Our data show that effluxes of K(+), H(+), Na(+) and Ca(2+) are localized to the region of the excretory pore, consistent with release of these ions from the excretory cell, and that effluxes increase after experimental preloading with Na(+), K(+) or Ca(2+). In addition, the hypodermis is a site of Na(+) influx.


Assuntos
Caenorhabditis elegans/metabolismo , Transporte de Íons/fisiologia , Animais , Transporte Biológico Ativo/fisiologia , Cálcio/metabolismo , Concentração de Íons de Hidrogênio , Levamisol/farmacologia , Microeletrodos , Potássio/metabolismo , Sódio/metabolismo
16.
J Exp Biol ; 217(Pt 23): 4193-202, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25278476

RESUMO

The rigid crustacean exoskeleton, the cuticle, is composed of the polysaccharide chitin, structural proteins and mineral deposits. It is periodically replaced to enable growth and its construction is an energy-demanding process. Ecdysis, the shedding event of the old cuticle, is preceded by a preparatory phase, termed premolt, in which the present cuticle is partially degraded and a new one is formed underneath it. Procambarus clarkii (Girard 1852), an astacid crustacean, was used here to comprehensively examine the changing patterns of gene expression in the hypodermis underlying the cuticle of the carapace at seven time points along ~14 premolt days. Next generation sequencing was used to construct a multi-tissue P. clarkii transcript sequence assembly for general use in a variety of transcriptomic studies. A reference transcriptome was created here in order to perform digital transcript expression analysis, determining the gene expression profiles in each of the examined premolt stages. The analysis revealed a cascade of sequential expression events of molt-related genes involved in chitin degradation, synthesis and modification, as well as synthesis of collagen and four groups of cuticular structural genes. The new description of major transcriptional events during premolt and the determination of their timing provide temporal markers for future studies of molt progress and regulation. The peaks of the expression of the molt-related genes were preceded by expression peaks of cytoskeletal genes that are hypothesized to be essential for premolt progress through regulating protein synthesis and/or transport, probably by remodeling the cytoskeletal structure.


Assuntos
Astacoidea/genética , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Muda/fisiologia , Animais , Astacoidea/crescimento & desenvolvimento , Astacoidea/metabolismo , Quitina/metabolismo , Citoesqueleto/metabolismo , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Muda/genética , Proteínas/metabolismo , Transcriptoma
17.
J Cosmet Dermatol ; 22(9): 2534-2541, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37128828

RESUMO

BACKGROUND: Recent studies demonstrate that PDO threads, after being introduced into the facial skin, provide benefits due to collagen formation around the thread and improved vascularization. AIMS: This work aims to report the ultrasound and photographic follow-up after the execution of the facelift thread technique, thus evaluating the anti-aging treatment that PDO threads will provide for human facial skin. METHODS: The facelift will be performed using PDO thread 18G cannulated Sculpt i- Thread FML 100 × 185 mm, and 29G PDO thread Needled Flat i-Thread 38 × 50 mm. A total of 10 patients were selected for the study; all of them had medium-grade facial ptosis and aged 40-50 years old. In order to control tissue changes after thread, insertion ultrasound measurements will be made with Philips ultrasound 12 MHz linear probe at maximum resolution, initial evaluations and control of 30, 60, 90, and 120 days, measuring the skin layers: epidermis\dermis and hypodermis. Photographic control was performed before and after 120 days of intrusion of the PDO threads. RESULTS: The formation of collagen around the PDO thread was evidenced through ultrasound images in all patients in this study, as well as improvement in the appearance of the skin and sagging, evaluated by photographic control. CONCLUSIONS: We can define that the PDO threads used for the facelift are effective in the formation of collagen around the thread (observed through the increase in the dermal layer), and improvement of the condition of the anti-aging factor through sagging skin, vascularization and thinning of the superficial fat layer (observed through the reduction of the subcutaneous or hypodermis layer).


Assuntos
Ritidoplastia , Envelhecimento da Pele , Humanos , Adulto , Pessoa de Meia-Idade , Ritidoplastia/métodos , Face , Pele/diagnóstico por imagem , Colágeno
18.
Life (Basel) ; 13(3)2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36983991

RESUMO

Recently, the superficial fascia has been recognized as a specific anatomical structure between the two adipose layers-the superficial adipose tissue (SAT) and the deep adipose tissue (DAT). The evaluation of specific characteristics of cells, fibers, blood circulation, and innervation has shown that the superficial fascia has a clear and distinct anatomical identity, but knowledge about lymphatic vessels in relation to the superficial fascia has not been described. The aim of this study was to evaluate the presence of lymphatic vessels in the hypodermis, with a specific focus on the superficial fascia and in relation to the layered subdivision of the subcutaneous tissue into SAT and DAT. Tissue specimens were harvested from three adult volunteer patients during abdominoplasty and stained with D2-40 antibody for the lymphatic endothelium. In the papillary dermis, a huge presence of lymphatic vessels was highlighted, parallel to the skin surface and embedded in the loose connective tissue. In the superficial adipose tissue, thin lymphatic vessels (mean diameter of 11.6 ± 7.71 µm) were found, close to the fibrous septa connecting the dermis to the deeper layers. The deep adipose tissue showed a comparable overall content of lymphatic vessels with respect to the superficial layer; they followed the blood vessel and had a larger diameter. In the superficial fascia, the lymphatic vessels showed higher density and a larger diameter, in both the longitudinal and transverse directions along the fibers, as well as vessels that intertwined with one another, forming a rich network of vessels. This study demonstrated a different distribution of the lymphatic vessels in the various subcutaneous layers, especially in the superficial fascia, and the demonstration of the variable gauge of the vessels leads us to believe that they play different functional roles in the collection and transport of interstitial fluid-important factors in various surgical and rehabilitation fields.

19.
Front Neuroanat ; 16: 981426, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36106154

RESUMO

The superficial fascia has only recently been recognized as a specific anatomical structure. Furthermore, whereas it is actually recognized that the innervation of the deep/muscular fascia plays a key role in proprioception and nociception, there are very few studies that have analyzed these characteristics in the superficial fascia. In this work, our group analyzed two different anatomical districts (abdomen and thigh), from volunteer patients, undergoing surgery procedures. Each sample was processed for histological analysis by Hematoxylin&Eosin, and by immunohistochemistry stainings (in 5-micron-paraffin embedded section and in cryosectioned free floating samples), with antibodies specific for nerve fibers: S100 antibody for myelinating and non-myelinating Schwann cells, PGP9.5 antibody as pan-neuronal marker, tyrosine hydroxylase for autonomic innervation. The results revealed a huge innervation: the nervous structures were found above all around blood vessels and close to adipocytes, but they penetrated also in the connective tissue itself and are found in the midst of fibro-adipose tissue. The tissue is pervaded by both thin (mean diameter of 4.8 ± 2.6 µm) and large nerve fiber bundles of greater diameter (21.1 ± 12.2 µm). The ratio S100/TH positivity was equal to 2.96, with a relative percentage of autonomic innervation with of 33.82%. In the light of these findings is evident that the superficial fasciae have a clear and distinct anatomical identity and a specific innervation, which should be considered to better understand their role in thermoregulation, exteroception and pain perception. The knowledge of the superficial fascia may improve grading and developing of different manual approach for treatments of fascial dysfunctions, and the understanding of how some factors like temperature or manual therapies can have an impact on sensitivity of the fascia.

20.
J Cosmet Dermatol ; 21(10): 4631-4636, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35199449

RESUMO

BACKGROUND: Gynoid lipodystrophy is one of the most common cosmetical problems in women. AIMS: The study aims to examine the pathomorphology and histology of subcutaneous tissue in women with gynoid lipodystrophy exposed to local compression/vibration therapy using a non-invasive Beautylizer Therapy Cosmospheres V medical device. METHODS: The study enrolled 25 virtually healthy women aged 25-45 years with gynoid lipodystrophy grades I and II. The women included in the study completed a 10-session month-long therapeutic course with a non-invasive Beautylizer Therapy Cosmospheres V medical device. Bioptic punch-size samples were taken from the gluteal region prior to and following the 10-session therapy course with the device. RESULTS: After completing a 10-session treatment course, a decrease in the mean adipocyte area from 123.08 ± 13.60 µm to 67.14 ± 4.20 µm was observed in punch bioptic samples of subcutaneous fat tissues of women with gynoid lipodystrophy as compared with the pre-treatment indices. CONCLUSION: Thus, local application of 10-session therapy with a non-invasive Beautylizer Therapy Cosmospheres V medical device in women with gynoid lipodystrophy demonstrated a positive effect on the histological structure of the hypodermis.


Assuntos
Lipodistrofia , Tela Subcutânea , Humanos , Feminino , Projetos Piloto , Vibração , Lipodistrofia/terapia , Lipodistrofia/patologia , Gordura Subcutânea
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