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1.
Exp Physiol ; 109(3): 380-392, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38063067

RESUMO

Heavy training has been reported to be immunosuppressive in athletes and lead to blunted cortisol responses to exercise. Cortisol elevates the number of dendritic cells (DCs), key antigen-presenting cells that interact with T cells to initiate an immune response. Reproducible cortisol responses to a 30-min cycle test have been identified but were based on percentage of work rate maximum. To ensure physiological consistency, submaximal anchors, that is, ventilatory threshold (VT1 ) should prescribe intensity. This study aims to assess the reproducibility of the DC and T cell responses to an adapted stress test to assess its usefulness in assessing DC dysfunction with intensified training. Twelve males cycled for 1 min at 20% below VT1 and 4 min at 50% between VT1 and V ̇ O 2 max ${\dot{V}}_{{{\mathrm{O}}}_{\mathrm{2}}\max }$ , for 30 min (20/50), with blood samples pre-, post- and 30 min post-exercise. This was repeated twice, 2-7 days apart. Flow cytometry assessed total DCs, plasmacytoid DCs, myeloid DCs, total T cells, T helper cells and T cytotoxic cells. No significant trial or interaction effects were found for any variable. A significant main effect of time for all variables was found; immune cells increased from pre- to post-exercise and decreased to baseline 30 min post-exercise, apart from plasmacytoid DCs, which remained elevated 30 min post-exercise. Intraclass correlation coefficients showed overall good-to-excellent reliability for all immune cells, with smallest real difference and Bland-Altman analysis verifying high reproducibility between trials. These results suggest that the 20/50 exercise test induces reproducible DC and T cell count changes, which, implemented before and after a period of intensified training, may highlight the negative states of overtraining.


Assuntos
Hidrocortisona , Linfócitos T , Masculino , Humanos , Reprodutibilidade dos Testes , Células Dendríticas , Contagem de Células
2.
Mol Cell Biochem ; 476(11): 4133-4137, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34312783

RESUMO

Chronic kidney disease (CKD) is a renal dysfunction that can lead to high rates of mortality and morbidity, particularly when coupled with late diagnosis. CKD has become a major health problem due to its challenging detection at early stages when clear symptoms are yet to be presented. Thus, CKD is likely to be identified when the substantive conditions of the disease are manifest. In order to address the development of the disease and provide necessary treatments at the initial stage, the investigation of new biomarkers and metabolites associated with early detection of CKD are needed. Identified metabolites could be used to confirm the presence of the disease, obtain information on its mechanism and facilitate the development of novel pharmaceutical treatments. Such metabolites may be detected from biofluids and tissues using a range of analytical techniques. There are a number of metabolites that have been identified by mass spectrometry at high sensitivities, whilst the detection of metabolites directly from biofluids using NMR could present a more rapid way to expand our understanding of this disease. This review is focused on NMR-based metabolomics associated with CKD in humans and animals.


Assuntos
Saúde Única , Insuficiência Renal Crônica/diagnóstico , Animais , Biomarcadores/análise , Diagnóstico Precoce , Humanos , Espectroscopia de Ressonância Magnética/métodos , Espectrometria de Massas/métodos , Metabolômica/métodos , Insuficiência Renal Crônica/metabolismo , Insuficiência Renal Crônica/terapia
3.
Biogerontology ; 19(6): 497-517, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30374678

RESUMO

Human adult stem cell research is a highly prolific area in modern tissue engineering as these cells have significant potential to provide future cellular therapies for the world's increasingly aged population. Cellular therapies require a smart biomaterial to deliver and localise the cell population; protecting and guiding the stem cells toward predetermined lineage-specific pathways. The cells, in turn, can provide protection to biomaterials and increase its longevity. The right combination of stem cells and biomaterials can significantly increase the therapeutic efficacy. Adult stem cells are utilised to target many changes that negatively impact tissue functions with age. Understanding the underlying mechanisms that lead to changes brought about by the ageing process is imperative as ageing leads to many detrimental effects on stem cell activation, maintenance and differentiation. The circadian clock is an evolutionarily conserved timing mechanism that coordinates physiology, metabolism and behavior with the 24 h solar day to provide temporal tissue homeostasis with the external environment. Circadian rhythms deteriorate with age at both the behavioural and molecular levels, leading to age-associated changes in downstream rhythmic tissue physiology in humans and rodent models. In this review, we highlight recent advances in our knowledge of the role of circadian clocks in adult stem cell maintenance, driven by both cell-autonomous and tissue-specific factors, and the mechanisms by which they co-opt various cellular signaling pathways to impose temporal control on stem cell function. Future research investigating pharmacological and lifestyle interventions by which circadian rhythms within adult stem niches can be manipulated will provide avenues for temporally guided cellular therapies and smart biomaterials to ameliorate age-related tissue deterioration and reduce the burden of chronic disease.


Assuntos
Células-Tronco Adultas/fisiologia , Relógios Circadianos/fisiologia , Regeneração , Animais , Diferenciação Celular , Proliferação de Células , Autorrenovação Celular , Humanos
4.
Calcif Tissue Int ; 100(1): 95-106, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27796463

RESUMO

Accelerating the integration of a joint replacement or the healing of a bone fracture, particularly a complicated non-union fracture, would improve patient welfare and decrease healthcare costs. Currently, an autologous bone graft is the gold standard method for the treatment of complicated non-union fractures, but it is not always possible to harvest such a graft. A proactive highly inductive so-called smart material approach is pertinent in these cases. In this study, the surface chemistry of a previously approved material with desirable bulk material properties was modified to investigate its potential as an economical and effective alternative. The objective was to create stable synthetic chemical coatings that could guide cells along the osteogenic lineage required to generate mineralised tissue that would induce and accelerate bone healing. Primary human osteoblast-like cells were cultured in vitro for 7, 14 and 28 days on amine-terminated (chain length in the range 3-11) silane-modified glass surfaces with controlled nanotopography, to determine how surface chemistry and nanotopography change osteoblast function. The materials were characterised using atomic force microscopy (AFM), scanning electron microscopy (SEM), water contact angle (WCA) and a novel ninhydrin assay. The cells were analysed using qRT-PCR, von Kossa tinctural staining for mineralisation, and visualised using both transmitted white light and electron microscopy. Bone-like nodules, quantified using microscopy, only formed on the short-chain (chain length 3 and 4) amines after 7 days, as did the up-regulation of sclerostin, suggestive of a more mature osteoblast phenotype. In this paper, we report more rapid nodule formation than has previously been observed, without the addition of exogenous factors in the culture medium. This suggests that the coating would improve the integration of implants with bone or be the basis of a smart biomaterial that would accelerate the bone regeneration process.


Assuntos
Diferenciação Celular/fisiologia , Osteoblastos/citologia , Osteócitos/citologia , Regeneração Óssea/fisiologia , Osso e Ossos/citologia , Calcificação Fisiológica/fisiologia , Técnicas de Cultura de Células/métodos , Células Cultivadas , Humanos , Microscopia de Força Atômica/métodos , Osteogênese/fisiologia , Propriedades de Superfície
5.
World J Surg ; 40(11): 2598-2602, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27230397

RESUMO

BACKGROUND: Double-gloving is endorsed by a number of healthcare authorities worldwide, on the basis that it promotes patient and surgeon safety; adoption of this practice amongst surgeons remains limited, based upon anecdotal reporting that double-gloving may compromise surgical technique due to impaired dexterity and sensation. The aim of this study is to formally investigate and demonstrate the effect of double-gloving upon the quality of knot tying, an essential surgical skill. METHODS: An international cohort of practising general surgeons hand tied surgical knots, under both single-gloved and double-gloved conditions, using monofilament and braided sutures, at two different gauges. Half of the participants tied single-gloved first. The mechanical strength of the knots was determined by tensile testing, and each knot was given a knot quality score (KQS), a validated assessment of knot quality. RESULTS AND CONCLUSIONS: 1466 knots were tested. Double-gloving was shown to reduce KQS for all suture types, compared to knots tied under single-gloved conditions (p = 0.001). There was no difference in the KQS of the double-gloved ties between those who routinely double-gloved and those who did not (p = 0.640). The OR showed that double-gloving reduced the KQS by 24 % overall, with the effect being much more prominent when the finer 4.0 suture was used, as knot quality was reduced by almost 50 % (95 % CI 13-93 %). Double-gloving impairs the quality of knot tying, and therefore, surgeons should consider other precautions to ensure patient and surgeon safety. These findings also question the validity of recommendations that surgeons should double-glove as a routine.


Assuntos
Luvas Cirúrgicas , Técnicas de Sutura/normas , Suturas , Feminino , Humanos , Masculino , Segurança do Paciente , Resistência à Tração
6.
J Mater Sci Mater Med ; 26(5): 178, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25893385

RESUMO

Advances in material sciences have enabled the fabrication of biomaterials which are able to provide the requisite cues to stimulate cells to behave in a specific way. Nanoscale surface topographies are well known to be able to positively influence cell-substrate interactions. This study reports on a novel series of poly(ε-caprolactone) PCL and poly(methyl methacrylate) demixed nanotopographic films as non-biological cell-stimulating cues. The topographic features observed ranged from nanoislands to nanopits. PMMA was observed to segregate to the air interface, while PCL preferred the substrate interface. Preliminary response of human mesenchymal stem cells to these surfaces indicated that the substrate with nanoisland topography has the potential to differentiate to osteogenic, chondrogenic and adipogenic lineages.


Assuntos
Condrócitos/citologia , Células-Tronco Mesenquimais/citologia , Nanoestruturas/química , Osteoblastos/citologia , Poliésteres/química , Polimetil Metacrilato/química , Materiais Biocompatíveis/síntese química , Diferenciação Celular/fisiologia , Células Cultivadas , Condrócitos/fisiologia , Condrogênese/fisiologia , Humanos , Teste de Materiais , Células-Tronco Mesenquimais/fisiologia , Nanoestruturas/ultraestrutura , Osteoblastos/fisiologia , Osteogênese/fisiologia , Propriedades de Superfície
7.
Wound Repair Regen ; 22(2): 174-86, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24611980

RESUMO

It is known that pH has a role to play in wound healing. In particular, pH has been shown to affect matrix metalloproteinase activity, tissue inhibitors of matrix metalloproteinases activity, fibroblast activity, keratinocyte proliferation, microbial proliferation, and also immunological responses in a wound; the patient's defense mechanisms change the local pH of a wound to effect microorganism invasion and proliferation; this pH change has been found to affect the performance of antimicrobials, and therefore the efficacy in biological environments directly relevant to wound healing. Based on the available body of scientific evidence to date, it is clear that pH has a role to play in both the healing of and treatment of chronic and acute wounds. It is the purpose of this review to evaluate the published knowledge base that concerns the effect of pH changes, the role it plays in wound healing and biofilm formation, and how it can affect treatment efficacy and wound management strategies.


Assuntos
Biofilmes/crescimento & desenvolvimento , Cicatrização , Ferimentos e Lesões/metabolismo , Anti-Infecciosos/administração & dosagem , Biofilmes/efeitos dos fármacos , Proliferação de Células , Fibroblastos , Humanos , Concentração de Íons de Hidrogênio , Linfócitos , Macrófagos , Metaloproteinases da Matriz/metabolismo , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Cicatrização/efeitos dos fármacos , Infecção dos Ferimentos/tratamento farmacológico , Infecção dos Ferimentos/metabolismo , Infecção dos Ferimentos/microbiologia , Infecção dos Ferimentos/fisiopatologia , Ferimentos e Lesões/tratamento farmacológico , Ferimentos e Lesões/fisiopatologia
8.
Sci Rep ; 14(1): 11065, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38744933

RESUMO

The development of stretchable electronic devices is a critical area of research for wearable electronics, particularly electronic textiles (e-textiles), where electronic devices embedded in clothing need to stretch and bend with the body. While stretchable electronics technologies exist, none have been widely adopted. This work presents a novel and potentially transformative approach to stretchable electronics using a ubiquitous structure: the helix. A strip of flexible circuitry ('e-strip') is twisted to form a helical ribbon, transforming it from flexible to stretchable. A stretchable core-in this case rubber cord-supports the structure, preventing damage from buckling. Existing helical electronics have only extended to stretchable interconnects between circuit modules, and individual components such as printed helical transistors. Fully stretchable circuits have, until now, only been produced in planar form: flat circuits, either using curved geometry to enable them to stretch, or using inherently stretchable elastomer substrates. Helical e-strips can bend along multiple axes, and repeatedly stretch between 30 and 50%, depending on core material and diameter. LED and temperature sensing helical e-strips are demonstrated, along with design rules for helical e-strip fabrication. Widely available materials and standard fabrication processes were prioritized to maximize scalability and accessibility.

9.
ACS Appl Bio Mater ; 7(5): 2872-2886, 2024 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-38721671

RESUMO

Antimicrobial coatings provide protection against microbes colonization on surfaces. This can prevent the stabilization and proliferation of microorganisms. The ever-increasing levels of microbial resistance to antimicrobials are urging the development of alternative types of compounds that are potent across broad spectra of microorganisms and target different pathways. This will help to slow down the development of resistance and ideally halt it. The development of composite antimicrobial coatings (CACs) that can host and protect various antimicrobial agents and release them on demand is an approach to address this urgent need. In this work, new CACs based on microsized hybrids of calcium carbonate (CaCO3) and silver nanoparticles (AgNPs) were designed using a drop-casting technique. Polyvinylpyrrolidone and mucin were used as additives. The CaCO3/AgNPs hybrids contributed to endowing colloidal stability to the AgNPs and controlling their release, thereby ensuring the antibacterial activity of the coatings. Moreover, the additives PVP and mucin served as a matrix to (i) control the distribution of the hybrids, (ii) ensure mechanical integrity, and (iii) prevent the undesired release of AgNPs. Scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared (FTIR) techniques were used to characterize the 15 µm thick CAC. The antibacterial activity was determined against Escherichia coli, methicillin-resistant Staphylococcus aureus (MRSA), and Pseudomonas aeruginosa, three bacteria responsible for many healthcare infections. Antibacterial performance of the hybrids was demonstrated at concentrations between 15 and 30 µg/cm2. Unloaded CaCO3 also presented bactericidal properties against MRSA. In vitro cytotoxicity tests demonstrated that the hybrids at bactericidal concentrations did not affect human dermal fibroblasts and human mesenchymal stem cell viability. In conclusion, this work presents a simple approach for the design and testing of advanced multicomponent and functional antimicrobial coatings that can protect active agents and release them on demand.


Assuntos
Antibacterianos , Carbonato de Cálcio , Teste de Materiais , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Prata , Carbonato de Cálcio/química , Carbonato de Cálcio/farmacologia , Prata/química , Prata/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Nanopartículas Metálicas/química , Humanos , Sobrevivência Celular/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Escherichia coli/efeitos dos fármacos , Propriedades de Superfície , Staphylococcus aureus/efeitos dos fármacos
10.
Exp Cell Res ; 318(4): 361-70, 2012 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-22198088

RESUMO

Controlling the fate of implanted hMSCs is one of the major drawbacks to be overcome to realize tissue engineering strategies. In particular, the effect of the inflammatory environment on hMSCs behaviour is poorly understood. Studying and mimicking the inflammatory process in vitro is a very complex and challenging task that involves multiple variables. This research addressed the questions using in vitro co-cultures of primary derived hMSCs together with human peripheral blood mononucleated cells (PBMCs); the latter are key agents in the inflammatory process. This work explored the in vitro phenotypic changes of hMSCs in co-culture direct contact with monocytes and lymphocytes isolated from blood using both basal and osteogenic medium. Our findings indicated that hMSCs maintained their undifferentiated phenotype and pluripotency despite the contact with PBMCs. Moreover, hMSCs demonstrated increased proliferation and were able to differentiate specifically down the osteogenic lineage pathway. Providing significant crucial evidence to support the hypothesis that inflammation and host defence mechanisms could be utilised rather than avoided and combated to provide for the successful therapeutic application of stem cell therapies.


Assuntos
Células-Tronco Adultas/transplante , Reação Hospedeiro-Enxerto/fisiologia , Inflamação/diagnóstico , Adulto , Células-Tronco Adultas/imunologia , Células-Tronco Adultas/fisiologia , Terapia Baseada em Transplante de Células e Tecidos/efeitos adversos , Terapia Baseada em Transplante de Células e Tecidos/métodos , Células Cultivadas , Técnicas de Cocultura , Citocinas/genética , Citocinas/metabolismo , Regulação da Expressão Gênica , Reação Hospedeiro-Enxerto/imunologia , Humanos , Inflamação/complicações , Inflamação/fisiopatologia , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/fisiologia , Osteogênese/genética , Osteogênese/fisiologia , Fenótipo , Prognóstico , Resultado do Tratamento
11.
Cells ; 12(2)2023 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-36672248

RESUMO

The transition areas between different tissues, known as tissue interfaces, have limited ability to regenerate after damage, which can lead to incomplete healing. Previous studies focussed on single interfaces, most commonly bone-tendon and bone-cartilage interfaces. Herein, we develop a 3D in vitro model to study the regeneration of the bone-tendon-muscle interface. The 3D model was prepared from collagen and agarose, with different concentrations of hydroxyapatite to graduate the tissues from bones to muscles, resulting in a stiffness gradient. This graduated structure was fabricated using indirect 3D printing to provide biologically relevant surface topographies. MG-63, human dermal fibroblasts, and Sket.4U cells were found suitable cell models for bones, tendons, and muscles, respectively. The biphasic and triphasic hydrogels composing the 3D model were shown to be suitable for cell growth. Cells were co-cultured on the 3D model for over 21 days before assessing cell proliferation, metabolic activity, viability, cytotoxicity, tissue-specific markers, and matrix deposition to determine interface formations. The studies were conducted in a newly developed growth chamber that allowed cell communication while the cell culture media was compartmentalised. The 3D model promoted cell viability, tissue-specific marker expression, and new matrix deposition over 21 days, thereby showing promise for the development of new interfaces.


Assuntos
Células-Tronco Mesenquimais , Humanos , Células-Tronco Mesenquimais/metabolismo , Tendões , Osso e Ossos , Cartilagem , Músculos
12.
Eur Cell Mater ; 24: 249-65, 2012 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-23007910

RESUMO

Wound healing requires a fine balance between the positive and deleterious effects of reactive oxygen species (ROS); a group of extremely potent molecules, rate limiting in successful tissue regeneration. A balanced ROS response will debride and disinfect a tissue and stimulate healthy tissue turnover; suppressed ROS will result in infection and an elevation in ROS will destroy otherwise healthy stromal tissue. Understanding and anticipating the ROS niche within a tissue will greatly enhance the potential to exogenously augment and manipulate healing. Tissue engineering solutions to augment successful healing and remodelling of wounded or diseased tissue rely on a controlled balance between the constructive and destructive capacity of the leukocyte secretome, including ROS. This review comprehensively considers leukocyte derived ROS in tissue repair with particular interest in surgical intervention with inclusion of a biomaterial. The article considers ROS fundamental chemistry, formation, stimulation and clearance before applying this to discuss the implications of ROS in healing tissue with and without a biomaterial. We also systematically discuss ROS in leukocyte signalling and compare and contrast experimental means of measuring ROS.


Assuntos
Inflamação/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Cicatrização , Animais , Materiais Biocompatíveis/metabolismo , Humanos , Inflamação/cirurgia , Leucócitos/metabolismo , Engenharia Tecidual
13.
J Infect Dis ; 204(3): 451-8, 2011 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-21742845

RESUMO

BACKGROUND: Neutrophils are the predominant cell in the lung inflammatory infiltrate of infants with respiratory syncytial virus (RSV) bronchiolitis. Although it has previously been shown that neutrophils from both blood and bronchoalveolar lavage (BAL) are activated, little is understood about their role in response to RSV infection. This study investigated whether RSV proteins and mRNA are present in neutrophils from blood and BAL of infected infants. METHODS: We obtained blood and BAL samples from 20 infants with severe RSV bronchiolitis and 8 healthy control infants. Neutrophil RSV F, G, and N proteins, RSV N genomic RNA, and messenger RNA (mRNA) were quantified. RESULTS: RSV proteins were found in BAL and blood neutrophils in infants with RSV disease but not in neutrophils from healthy infants. BAL and blood neutrophils from infants with RSV disease, but not those from healthy infants, expressed RSV N genomic RNA, indicating uptake of whole virus; 17 of 20 BAL and 8 of 9 blood neutrophils from patients expressed RSV N mRNA. CONCLUSIONS: This work shows, for the first time, the presence of RSV proteins and mRNA transcripts within BAL and blood neutrophils from infants with severe RSV bronchiolitis.


Assuntos
Bronquiolite Viral/virologia , Líquido da Lavagem Broncoalveolar/virologia , Neutrófilos/virologia , Vírus Sinciciais Respiratórios/fisiologia , Bronquiolite Viral/imunologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Neutrófilos/fisiologia , RNA Mensageiro/análise , Vírus Sinciciais Respiratórios/genética , Vírus Sinciciais Respiratórios/isolamento & purificação , Proteínas Virais de Fusão/análise , Proteínas Virais de Fusão/fisiologia
14.
Sci Rep ; 12(1): 7972, 2022 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-35562402

RESUMO

This article focuses on the design and fabrication of flexible textile-based protein sensors to be embedded in wound dressings. Chronic wounds require continuous monitoring to prevent further complications and to determine the best course of treatment in the case of infection. As proteins are essential for the progression of wound healing, they can be used as an indicator of wound status. Through measuring protein concentrations, the sensor can assess and monitor the wound condition continuously as a function of time. The protein sensor consists of electrodes that are directly screen printed using both silver and carbon composite inks on polyester nonwoven fabric which was deliberately selected as this is one of the common backing fabric types currently used in wound dressings. These sensors were experimentally evaluated and compared to each other by using albumin protein solution of pH 7. A comprehensive set of cyclic voltammetry measurements was used to determine the optimal sensor design the measurement of protein in solution. As a result, the best sensor design is comprised of silver conductive tracks but a carbon layer as the working and counter electrodes at the interface zone. This design prevents the formation of silver dioxide and protects the sensor from rapid decay, which allows for the recording of consecutive measurements using the same sensor. The chosen printed protein sensor was able to detect bovine serum albumin at concentrations ranging from 30 to 0.3 mg/mL with a sensitivity of [Formula: see text]A/M. Further testing was performed to assess the sensor's ability to identify BSA from other interferential substances usually present in wound fluids and the results show that it can be distinguishable.


Assuntos
Prata , Têxteis , Bandagens , Carbono , Cicatrização
15.
PLoS One ; 17(12): e0278049, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36454864

RESUMO

BACKGROUND: Biopurification has been used to disclose an evolutionarily conserved inhibitory reproductive hormone involved in tissue mass determination. A (rat) bioassay-guided physicochemical fractionation using ovine materials yielded via Edman degradation a 14-residue amino acid (aa) sequence. As a 14mer synthetic peptide (EPL001) this displayed antiproliferative and reproduction-modulating activity, while representing only a part of the native polypeptide. Even more unexpectedly, a scrambled-sequence control peptide (EPL030) did likewise. METHODS: Reproduction has been investigated in the nematode Steinernema siamkayai, using a fermentation system supplemented with different concentrations of exogenous hexapeptides. Peptide structure-activity relationships have also been studied using prostate cancer and other mammalian cells in vitro, with peptides in solution or immobilized, and via the use of mammalian assays in vivo and through molecular modelling. RESULTS: Reproduction increased (x3) in the entomopathogenic nematode Steinernema siamkayai after exposure to one synthetic peptide (IEPVFT), while fecundity was reduced (x0.5) after exposure to another (KLKMNG), both effects being dose-dependent. These hexamers are opposite ends of the synthetic peptide KLKMNGKNIEPVFT (EPL030). Bioactivity is unexpected as EPL030 is a control compound, based on a scrambled sequence of the test peptide MKPLTGKVKEFNNI (EPL001). EPL030 and EPL001 are both bioinformatically obscure, having no convincing matches to aa sequences in the protein databases. EPL001 has antiproliferative effects on human prostate cancer cells and rat bone marrow cells in vitro. Intracerebroventricular infusion of EPL001 in sheep was associated with elevated growth hormone in peripheral blood and reduced prolactin. The highly dissimilar EPL001 and EPL030 nonetheless have the foregoing biological effects in common in mammalian systems, while being divergently pro- and anti-fecundity respectively in the nematode Caenorhabditis elegans. Peptides up to a 20mer have also been shown to inhibit the proliferation of human cancer and other mammalian cells in vitro, with reproductive upregulation demonstrated previously in fish and frogs, as well as nematodes. EPL001 encodes the sheep neuroendocrine prohormone secretogranin II (sSgII), as deduced on the basis of immunoprecipitation using an anti-EPL001 antibody, with bespoke bioinformatics. Six sSgII residues are key to EPL001's bioactivity: MKPLTGKVKEFNNI. A stereospecific bimodular tri-residue signature is described involving simultaneous accessibility for binding of the side chains of two specific trios of amino acids, MKP & VFN. An evolutionarily conserved receptor is conceptualised having dimeric binding sites, each with ligand-matching bimodular stereocentres. The bioactivity of the 14mer control peptide EPL030 and its hexapeptide progeny is due to the fortuitous assembly of subsets of the novel hormonal motif, MKPVFN, a default reproductive and tissue-building OFF signal.


Assuntos
Neoplasias da Próstata , Rabditídios , Humanos , Masculino , Animais , Ovinos , Ratos , Reprodução , Mamíferos , Caenorhabditis elegans , Hormônios
16.
J Surg Res ; 168(1): e31-8, 2011 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21074784

RESUMO

BACKGROUND: Musculoskeletal reconstructive surgery often requires removal of significant quantities of bone tissue, such as the periosteum, causing critical problems following surgery like friction between different tissues and adhesion of soft tissues to the underlying bone. We studied the long-term host response and closure of large bone defects for periosteal reconstruction using Hyalonect, a novel membrane comprising knitted fibers of esterified hyaluronan, (HYAFF11). MATERIALS AND METHODS: For biological characterization, 162 rats were used in a defect model in which a section of the dorsal muscular fascia was removed, and the membrane behavior observed over 540 d using conventional histology, with sham operated rats as controls. In addition, Hyalonect was used to cover defects made in the humeri of 7 dogs, filled with a variety of conventional bone filling compounds, and the regeneration process observed after 6 wks using histology. RESULTS: Low levels of inflammation were observed in the dorsal muscle fascia defect model, with cellular colonization of the mesh by 30 d, vascularization by 120 days, matrix fiber organization by 270 d, and the appearance of connective tissue identical to the surrounding tissue between 365 and 540 d, without the formation of fibrotic tissue. In addition, Hyalonect was shown to allow the regeneration of bone within the humeral defects whilst preventing fibrotic tissue in-growth, and allowing regeneration of tissue which, by 6 wk, had begun to resemble natural periosteal tissue. CONCLUSION: Hyalonect is suitable for improving the outcome of the final phases of orthopedic and trauma reconstructive surgical procedures, especially in the reconstruction of periosteal tissue.


Assuntos
Implantes Absorvíveis , Fáscia/patologia , Fasciotomia , Úmero/cirurgia , Ácido Hialurônico/uso terapêutico , Telas Cirúrgicas , Animais , Regeneração Óssea/fisiologia , Fibrose/prevenção & controle , Úmero/fisiologia , Masculino , Modelos Animais , Ratos , Ratos Sprague-Dawley , Resultado do Tratamento
17.
Womens Health (Lond) ; 17: 17455065211058553, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34798792

RESUMO

OBJECTIVES: Menstrual cups come in a range of shapes, sizes, and firmnesses, but unlike tampons are not categorized in any way. With these factors having an impact on product leaks and comfort, as well as being linked to illness and injury, women need the same level of transparency when purchasing a menstrual cup. The comparison of physical and mechanical properties of menstrual cups will be the first step to achieve this. METHODS: In October 2020, 14 popular and highly rated menstrual cups underwent quantitative comparison in laboratory settings (the United Kingdom), and they were compared in terms of their dimensions, volume, and compressive strength (firmness) using the Instron Universal Testing System. The overall designs were compared including shape, material, and features. RESULTS: Although all the products in this comparison were marketed to women below 30 years of age having never given birth, total volume varied from 18.88 mL to 38.14 mL, and compressive load to compress the menstrual cup 50% (±0.5%) maximum diameter varied from 3.39 N to 13.92 N. CONCLUSIONS: Women are not sufficiently informed when choosing a menstrual cup. With no correlation between menstrual cup size, shape, and its volume, or material, shape, and its firmness, consumers cannot estimate which menstrual cup might be most suitable, and incorrect choice could cause injury. Transparency is needed across menstrual cup brands. With this and further regulation, women will make an informed decision to choose the correct menstrual cup and minimize injury. This work recommends firmness categories, ranging from 'very soft' to 'very firm' as a first step.


Assuntos
Produtos de Higiene Menstrual , Menstruação , Feminino , Humanos
18.
Tissue Eng Part B Rev ; 27(6): 548-571, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33176607

RESUMO

The regeneration of the musculoskeletal system has been widely investigated. There is now detailed knowledge about the organs composing this system. Research has also investigated the zones between individual tissues where physical, mechanical, and biochemical properties transition. However, the understanding of the regeneration of musculoskeletal interfaces is still lacking behind. Numerous disorders and injuries can degrade or damage tissue interfaces. Their inability to regenerate can delay the tissue repair and regeneration process, leading to graft instability, high morbidity, and pain. Moreover, the knowledge of the mechanism of tissue interface development is not complete. This review presents an overview of the most recent approaches of the regeneration of musculoskeletal interfaces, including the latest in vitro, preclinical, and clinical studies. Impact statement Interfaces between soft and hard tissues are ubiquitous within the body. These transition zones are crucial for joint motion, stabilisation and load transfer between tissues, but do not seem to regenerate well after injury or deterioration. The knowledge about their biology is vast, but little is known about their development. Various musculoskeletal disorders in combination with risk factors including aging and unhealthy lifestyle, can lead to local imbalances, misalignments, inflammation, pain and restricted mobility. Our manuscript reviews the current approaches taken to promote the regeneration of musculoskeletal interfaces through in vitro, pre-clinical and clinical studies.


Assuntos
Doenças Musculoesqueléticas , Sistema Musculoesquelético , Humanos , Doenças Musculoesqueléticas/terapia , Regeneração , Engenharia Tecidual , Cicatrização
19.
J Biomed Mater Res B Appl Biomater ; 109(11): 1713-1723, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33749114

RESUMO

Enriching a biomaterial surface with specific chemical groups has previously been considered for producing surfaces that influence cell response. Silane layer deposition has previously been shown to control mesenchymal stem cell adhesion and differentiation. However, it has not been used to investigate neuronal or Schwann cell responses in vitro to date. We report on the deposition of aminosilane groups for peripheral neurons and Schwann cells studying two chain lengths: (a) 3-aminopropyl triethoxysilane (short chain-SC) and (b) 11-aminoundecyltriethoxysilane (long chain-LC) by coating glass substrates. Surfaces were characterised by water contact angle, AFM and XPS. LC-NH2 was produced reproducibly as a homogenous surface with controlled nanotopography. Primary neuron and NG108-15 neuronal cell differentiation and primary Schwann cell responses were investigated in vitro by S100ß, p75, and GFAP antigen expression. Both amine silane surface supported neuronal and Schwann cell growth; however, neuronal differentiation was greater on LC aminosilanes versus SC. Thus, we report that silane surfaces with an optimal chain length may have potential in peripheral nerve repair for the modification and improvement of nerve guidance devices.


Assuntos
Técnicas de Cultura de Células , Diferenciação Celular , Células-Tronco Mesenquimais/metabolismo , Neurônios/metabolismo , Células de Schwann/metabolismo , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , Células-Tronco Mesenquimais/citologia , Neurônios/citologia , Ratos , Células de Schwann/citologia , Propriedades de Superfície
20.
BMC Res Notes ; 14(1): 469, 2021 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-34952633

RESUMO

OBJECTIVE: The use of benchtop metabolic profiling technology based on nuclear magnetic resonance (NMR) was evaluated in a small cohort of cats with a view to applying this as a viable and rapid metabolic tool to support clinical decision making. RESULTS: Urinary metabolites were analysed from four subjects consisting of two healthy controls and two chronic kidney disease (CKD) IRIS stage 2 cases. The study identified 15 metabolites in cats with CKD that were different from the controls. Among them were acetate, creatinine, citrate, taurine, glycine, serine and threonine. Benchtop NMR technology is capable of distinguishing between chronic kidney disease case and control samples in a pilot feline cohort based on metabolic profile. We offer perspectives on the further development of this pilot work and the potential of the technology, when combined with sample databases and computational intelligence techniques to offer a clinical decision support tool not only for cases of renal disease but other metabolic conditions in the future.


Assuntos
Metabolômica , Insuficiência Renal Crônica , Animais , Gatos , Creatinina , Espectroscopia de Ressonância Magnética , Metaboloma
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