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Stem cells have been shown to have potential as a new therapy for burns and promote wound healing through decreasing inflammation and increasing angiogenesis. Multipotent adult progenitor cells (MAPC® cells) are a subpopulation of bone marrow-derived stem cells with outstanding self-renewal and differentiation capacity. MAPC cells also secrete a wide range of cytokines which can affect cellular activities. This article aimed to examine the effects of MAPC cells treatment on burn injury repair using a mouse model of partial thickness burn injury. The immunomodulatory effect of MAPC cells was investigated in vitro using a simultaneous T-cell proliferation assay. Partial thickness burns were created on the dorsal surface of mice and MAPC cells were administered via intradermal injection to the wound margins 24 h post-burn injury. The burn tissues were analysed macroscopically to determine wound area and histologically assessed to determine wound width and rate of re-epithelialisation. Immunohistochemistry and ELISA were employed to assess cell proliferation, inflammation and angiogenesis and collagen deposition in the burn area. MAPC cells inhibit the proliferation of stimulated T cells in culture. Burns intradermally injected with MAPC cells showed a significant reduction in the macroscopic wound area, histologic wound width and had an increased rate of re-epithelialisation. Immunohistochemistry and ELISA analysis of burn tissues showed dampened inflammation evidenced by a reduction in neutrophilic infiltration and modulation of inflammatory cytokines. Angiogenesis within the burn area was also improved in MAPC cell treated mice. However, no significant effect of MAPC cell treatment was observed on extracellular matrix production. Treatment of burns with MAPC cells improved burn injury repair with reduced time to healing, decreased inflammation and increased angiogenesis. These findings demonstrate the promising effects of MAPC cells on burn injury repair and suggest MAPC cells as a candidate source for clinical cell therapies.
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Queimaduras , Cicatrização , Animais , Queimaduras/terapia , Inflamação , Camundongos , Reepitelização , Células-TroncoRESUMO
The use of mesenchymal stem cells (MSC) for the treatment of cutaneous wounds is currently of enormous interest. However, the broad translation of cell therapies into clinical use is hampered by their efficacy, safety, manufacturing and cost. MSCs release a broad repertoire of trophic factors and immunomodulatory cytokines, referred to as the MSC secretome, that has considerable potential for the treatment of cutaneous wounds as a cell-free therapy. In this review, we outline the current status of MSCs as a treatment for cutaneous wounds and introduce the potential of the MSC secretome as a cell-free alternative for wound repair. We discuss the challenges and provide insights and perspectives for the future development of the MSC secretome as well as identify its potential clinical translation into a therapeutic treatment.
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Citocinas/uso terapêutico , Fatores Imunológicos/uso terapêutico , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Proteoma/uso terapêutico , Cicatrização , Animais , Humanos , Imunomodulação , Medicina RegenerativaRESUMO
Pericytes are peri-vascular mural cells which have an important role in the homeostatic regulation of inflammatory and angiogenic processes. Flightless I (Flii) is a cytoskeletal protein involved in regulating cellular functions, but its involvement in pericyte activities during wound healing is unknown. Exacerbated inflammation and reduced angiogenesis are hallmarks of impaired diabetic healing responses, and strategies aimed at regulating these processes are vital for improving healing outcomes. To determine the effect of altering Flii expression on pericyte function, in vitro and in vivo studies were performed to assess the effect on healing, inflammation and angiogenesis in diabetic wounds. Here, we demonstrated that human diabetic wounds display upregulated expression of the Flii protein in conjunction with a depletion in the number of platelet derived growth factor receptor ß (PDGFRß) +/ neural glial antigen 2 (NG2) + pericytes present in the dermis. Human pericytes were found to be positive for Flii and attenuating its expression in vitro through siRNA knockdown led to enhanced proliferation, migration and angiogenic functions. Genetic knockdown of Flii in a streptozotocin-induced murine model of diabetes led to increased numbers of pericytes within the wound. This was associated with dampened inflammation, an increased rate of angiogenic repair and improved wound healing. Our findings show that Flii expression directly impacts pericyte functions, including proliferation, motility and angiogenic responses. This suggests that Flii regulation of pericyte function may be in part responsible for the changes in pericyte-related processes observed in diabetic wounds.
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Diabetes Mellitus/genética , Pé Diabético/genética , Inflamação/genética , Proteínas dos Microfilamentos/genética , Transativadores/genética , Cicatrização/genética , Animais , Proliferação de Células/genética , Proteínas do Citoesqueleto/genética , Complicações do Diabetes/genética , Complicações do Diabetes/patologia , Diabetes Mellitus/terapia , Pé Diabético/complicações , Pé Diabético/patologia , Humanos , Inflamação/complicações , Inflamação/patologia , Inflamação/terapia , Camundongos , Pericitos/metabolismo , Pericitos/patologiaRESUMO
Much of current research investigates the beneficial properties of mesenchymal stem cells (MSCs) as a treatment for wounds and other forms of injury. In this review, we bring attention to and discuss the role of the pericyte, a cell type which shares much of the differentiation potential and regenerative properties of the MSC as well as specific roles in the regulation of angiogenesis, inflammation and fibrosis. Pericytes have been identified as dysfunctional or depleted in many disease states, and observing the outcomes of pericyte perturbation in models of disease and wound healing informs our understanding of overall pericyte function and identifies these cells as an important target in the development of therapies to encourage healing.
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Células-Tronco Mesenquimais/citologia , Pericitos/citologia , Cicatrização , Animais , Humanos , Inflamação/terapia , Transplante de Células-Tronco Mesenquimais , Neovascularização Fisiológica , Pericitos/transplanteRESUMO
The re-investigation of [Bi2O2(OH)](NO3), dioxidodibismuth(III) hydroxide nitrate, on the basis of single-crystal X-ray diffraction data revealed an apparent structural phase transition of a crystal structure determined previously (space group Cmc21 at 173â K) to a crystal structure with lower symmetry (space group Pna21 at 100â K). The Cmc21 â Pna21 group-subgroup relationship between the two crystal structures is klassengleiche with index 2. In contrast to the crystal structure in Cmc21 with orientational disorder of the nitrate anion, disorder does not occur in the Pna21 structure. Apart from the disorder of the nitrate anion, the general structural set-up in the two crystal structures is very similar: [Bi2O2]2+ layers extend parallel to (001) and alternate with layers of (OH)- anions above and (NO3)- anions below the cationic layer. Whereas the (OH)- anion shows strong bonds to the BiIII cations, the (NO3)- anion weakly binds to the BiIII cations of the cationic layer. A rather weak O-Hâ¯O hydrogen-bonding inter-action between the (OH)- anion and the (NO3)- anion links adjacent sheets along [001].
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Chimeric antigen receptor (CAR)-T cell immunotherapy is a novel treatment that genetically modifies the patients' own T cells to target and kill malignant cells. However, identification of tumour-specific antigens expressed on multiple solid cancer types, remains a major challenge. P2X purinoceptor 7 (P2X7) is a cell surface expressed ATP gated cation channel, and a dysfunctional version of P2X7, named nfP2X7, has been identified on cancer cells from multiple tissues, while being undetectable on healthy cells. We present a prototype -human CAR-T construct targeting nfP2X7 showing potential antigen-specific cytotoxicity against twelve solid cancer types (breast, prostate, lung, colorectal, brain and skin). In xenograft mouse models of breast and prostate cancer, CAR-T cells targeting nfP2X7 exhibit robust anti-tumour efficacy. These data indicate that nfP2X7 is a suitable immunotherapy target because of its broad expression on human tumours. CAR-T cells targeting nfP2X7 have potential as a wide-spectrum cancer immunotherapy for solid tumours in humans.
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Neoplasias da Próstata , Masculino , Humanos , Animais , Camundongos , Imunoterapia , Encéfalo , Mama , Membrana Celular , Modelos Animais de DoençasRESUMO
TLR4 plays a pivotal role in orchestrating inflammation and tissue repair. Its expression has finally been balanced to initiate the early, robust immune response necessary for efficient repair without excessively amplifying and prolonging inflammation, which impairs healing. Studies show Flightless I (Flii) is an immunomodulator that negatively regulates macrophage TLR4 signalling. Using macrophages from Flii+/-, WT, and FliiTg/Tg mice, we have shown that elevated Flii reduces early TLR4 surface expression, delaying and reducing subsequent TNF secretions. In contrast, reduced Flii increases surface TLR4, leading to an earlier robust TNF peak. In Flii+/- mice, TLR4 levels peak earlier during wound repair, and overall healing is accelerated. Fewer neutrophils, monocytes and macrophages are recruited to Flii+/- wounds, leading to fewer TNF-positive macrophages, alongside an early peak and a robust shift to M2 anti-inflammatory, reparative Ym1+ and IL-10+ macrophages. Importantly, in diabetic mice, high Flii levels are found in plasma and unwounded skin, with further increases observed in their wounds, which have impaired healing. Lowering Flii in diabetic mice results in an earlier shift to M2 macrophages and improved healing. Overall, this suggests Flii regulation of TLR4 reduces early inflammation and decreases the M2 macrophage phenotype, leading to impaired healing.
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Proteínas dos Microfilamentos , Receptor 4 Toll-Like , Transativadores , Cicatrização , Animais , Diabetes Mellitus Experimental , Inflamação/genética , Inflamação/metabolismo , Macrófagos/metabolismo , Camundongos , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo , Receptor 4 Toll-Like/metabolismo , Transativadores/genética , Transativadores/metabolismo , Cicatrização/genética , Cicatrização/fisiologiaRESUMO
Synthetic and naturally occurring forms of tricopper orthotellurate, CuII3TeVIO6 (the mineral mcalpineite) have been investigated by 3D electron diffraction (3D ED), X-ray powder diffraction (XRPD), Raman and infrared (IR) spectroscopic measurements. As a result of the diffraction analyses, CuII3TeVIO6 is shown to occur in two polytypes. The higher-symmetric CuII3TeVIO6-1C polytype is cubic, space group Ia3, with a = 9.537â (1)â Å and V = 867.4â (3)â Å3 as reported in previous studies. The 1C polytype is a well characterized structure consisting of alternating layers of CuIIO6 octahedra and both CuIIO6 and TeVIO6 octahedra in a patchwork arrangement. The structure of the lower-symmetric orthorhombic CuII3TeVIO6-2O polytype was determined for the first time in this study by 3D ED and verified by Rietveld refinement. The 2O polytype crystallizes in space group Pcca, with a = 9.745â (3)â Å, b = 9.749â (2)â Å, c = 9.771â (2)â Å and V = 928.3â (4)â Å3. High-precision XRPD data were also collected on CuII3TeVIO6-2O to verify the lower-symmetric structure by performing a Rietveld refinement. The resultant structure is identical to that determined by 3D ED, with unit-cell parameters a = 9.56157â (19)â Å, b = 9.55853â (11)â Å, c = 9.62891â (15)â Å and V = 880.03â (2)â Å3. The lower symmetry of the 2O polytype is a consequence of a different cation ordering arrangement, which involves the movement of every second CuIIO6 and TeVIO6 octahedral layer by (1/4, 1/4, 0), leading to an offset of TeVIO6 and CuIIO6 octahedra in every second layer giving an ABAB* stacking arrangement. Syntheses of CuII3TeVIO6 showed that low-temperature (473â K) hydrothermal conditions generally produce the 2O polytype. XRPD measurements in combination with Raman spectroscopic analysis showed that most natural mcalpineite is the orthorhombic 2O polytype. Both XRPD and Raman spectroscopy measurements may be used to differentiate between the two polytypes of CuII3TeVIO6. In Raman spectroscopy, CuII3TeVIO6-1C has a single strong band around 730â cm-1, whereas CuII3TeVIO6-2O shows a broad double maximum with bands centred around 692 and 742â cm-1.
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Elétrons , Análise Espectral Raman , Difração de Pó , Espectrofotometria Infravermelho , Difração de Raios XRESUMO
Pericytes have the potential to be developed as a cell therapy for the treatment of wounds; however, the efficacy of any cell therapy relies on the successful delivery of intact and functioning cells. Here, the effect of delivering pericytes on wound repair was assessed alongside the development of a surface-functionalized pericyte patch. Plasma polymerization (PP) was used to functionalize the surface of silicone patches with heptylamine (HA) or acrylic acid (AA) monomers. Human pericytes were subsequently delivered to murine excisional wounds by intradermal injection or using the pericyte-laden patches and the comparative effects on wound healing, inflammation and revascularization determined. The AA surface provided the superior transfer of the cells to de-epidermized dermis. Excisional murine wounds treated either with pericytes injected directly into the wound or with the pericyte-laden AA patches showed improved healing with decreased neutrophil infiltration and reduced numbers of macrophages in the wounds. Pericyte delivery also enhanced angiogenesis through a mechanism independent of VEGF signalling. Pericytes, when delivered to wounds, improved healing responses by dampening inflammation and promoting angiogenesis. Delivery of pericytes using PP-AA-functionalized patches was equally as effective as direct injection of pericytes into wounds. Pericyte-functionalized dressings may therefore be a clinically relevant approach for the treatment of wounds.
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Pericitos/fisiologia , Cicatrização , Animais , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos SCID , Modelos AnimaisRESUMO
Crystals of the first synthetic copper tellurite arsenate, CuII5(TeIVO3)2(AsVO4)2 [systematic name pentacopper(II) bis-oxotellurate(IV) bis-oxoarsenate(V)], were grown by the chemical vapour transport method and structurally determined using single-crystal X-ray diffraction. CuII5(TeIVO3)2(AsVO4)2 possesses a novel structure type including a new topological arrangement of CuII and O atoms. CuII5(TeIVO3)2(AsVO4)2 is formed from a framework of two types of Jahn-Teller distorted [CuIIO6] octahedra (one of which is considerably elongated) and [CuIIO5] square pyramids, which are linked by edge-sharing to form chains and dimers and by corner-sharing to complete a three-dimensional framework. [AsVO4] tetrahedra and [TeIVO5] polyhedra bridge the edges of channels along the a-axis direction, with void space remaining for the TeIV stereoactive 5s2 lone pairs. A comparison is made between the crystal structure of CuII5(TeIVO3)2(AsVO4)2 and those of known compounds and minerals, in particular fumarolitic Cu minerals.
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Healing of the skin and oral mucosa utilises similar mechanisms of tissue repair, however, scarring and the rate of wound closure is vastly superior in the oral cavity suggesting differences between these two environments. One key difference is the phenotype of dermal fibroblasts compared to fibroblasts of gingival tissues. Human gingival fibroblasts (hGFs) are undifferentiated cells with multi-differentiation and self-renewal capacities. This study aimed to examine if delivering hGFs or their secretome, contained in hGF-conditioned media (hGF-CM), would improve healing of the skin and recapitulate features of oral healing. Human fibroblasts, keratinocytes and endothelial cells were first treated with hGF-CM and showed improved migration, proliferation and angiogenic functions. A significant reduction in macroscopic wound area and histologic dermal wound width, as well as an increased rate of re-epithelialisation, were observed in both hGFs and hGF-CM treated murine excisional wounds. This improvement was associated with reduced inflammation, increased angiogenesis and elevated collagen deposition. These findings demonstrate that treatment of dermal wounds with either hGFs or hGF-CM may provide beneficial gingival-like properties to dermal wounds and may be a potential opportunity for improving healing of the skin.
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BACKGROUND: Stem cell therapies have been widely investigated for their healing effects. However, the translation of these therapies has been hampered by the requirement to deliver live allogeneic or autologous cells directly to the wound in a clinical setting. Multipotent adult progenitor cells (MAPC® cells) are a subpopulation of bone marrow-derived adherent stem cells that secrete a wide range of factors known to accelerate the wound healing process. The aim of this study was to determine the impact of MAPC cells secretome on healing outcomes without the presence of MAPC cells. METHODS: The effect of MAPC-conditioned medium (MAPC-CM) on the capacity of keratinocytes, fibroblasts and endothelial cells to migrate and proliferate was determined in vitro using scratch wound closure and WST1 assay, respectively. The effect of MAPC-CM on collagen deposition and angiogenesis was also assessed using in vitro methods. Additionally, two excisional wounds were created on the dorsal surface of mice (n = 8/group) and 100 µL of 20× MAPC-CM were intradermally injected to the wound margins. Wound tissues were collected at 3, 7 and 14 days post-wounding and stained with H&E for microscopic analysis. Immunohistochemistry was performed to investigate inflammation, angiogenesis and collagen deposition in the wounds. RESULTS: Skin fibroblasts, keratinocytes and endothelial cells treated with MAPC-CM all showed improved rates of scratch closure and increased cellular proliferation. Moreover, fibroblasts treated with MAPC-CM deposited more collagens I and III and endothelial cells treated with MAPC-CM showed increased capillary tube formation. Murine excisional wounds intradermally injected with MAPC-CM showed a significant reduction in the wound area and an increase in the rate of reepithelialisation. The results also showed that inflammatory cell infiltration was decreased while an increase in angiogenesis, as well as collagens I and III expressions, was observed. CONCLUSION: These findings suggest that factors produced by MAPC cells can have an important effect on cutaneous wound healing by affecting skin cell proliferation and migration, balancing inflammation and improving the formation of extracellular matrix and angiogenesis. Development of stem cell-free therapy for the treatment of wounds may be a more clinically translatable approach for improving healing outcomes.
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Células Endoteliais , Cicatrização , Adulto , Animais , Meios de Cultivo Condicionados/farmacologia , Humanos , Inflamação , Camundongos , Células-Tronco Multipotentes , PeleRESUMO
Cryopreservation is an essential part of tissue banking and effective cryopreservation methods are critical for the development of cost-effective cell therapy products. Cell sheets are an attractive subset of cell therapy types, and cryopreservation has the potential to further drive down costs of allogeneic cell sheet therapy. This is currently a challenge as adhered cell monolayers are more susceptible to membrane damage during the freezing process. In this article, we investigate the performance of a surface-modified dressing for the cryopreservation of cells and strategies to improve cell recovery. Cryopreservation of multipotent adult progenitor cells (MAPC®) was performed on cells following their attachment to a surface for different periods of time. MAPC cells, given just 1 h to attach, washed off and were not recovered on the surface following thawing. Cells attached for longer periods, elongated further, and were more susceptible to damage from cryopreservation. A temporal window was identified that could allow cryopreservation on adherent surfaces where cells had attached to a surface without full elongation. By functionalizing the surface with coupled hyaluronic acid, cell spreading was initially retarded, thereby widening this temporal window. This approach demonstrates a novel method for enhancing the recovery of cryopreserved cell sheets on surfaces.
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Criopreservação/métodos , Ácido Hialurônico/química , Células-Tronco/citologia , Adesão Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Ácido Hialurônico/farmacologia , Polímeros/química , Células-Tronco/metabolismo , Propriedades de SuperfícieRESUMO
Impaired wound healing states in the elderly lead to substantial morbidity, mortality, and a cost to the US Health Services of over $9 billion per annum. In addition to intrinsic aging per se causing delayed healing, studies have suggested marked sex-differences in wound repair. We report that castration of male mice results in a striking acceleration of local cutaneous wound healing, and is associated with a reduced inflammatory response and increased hair growth. Using a hairless mouse model, we have demonstrated that testosterone reduction stimulates the healing response not through hair follicle epithelial/mesenchymal cell proliferation, but directly via effects on wound cell populations. We suggest that endogenous testosterone inhibits the cutaneous wound healing response in males and is associated with an enhanced inflammatory response. The mechanisms underlying the observed effects involve a direct upregulation of proinflammatory cytokine expression by macrophages in response to testosterone. Blockade of androgen action systemically, via receptor antagonism, accelerates healing significantly, suggesting a specific target for future therapeutic intervention in impaired wound healing states in elderly males.
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Receptores Androgênicos/fisiologia , Pele/metabolismo , Cicatrização , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Células Cultivadas , Citocinas/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Pelados , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Monócitos/metabolismo , Radioimunoensaio , Receptores Androgênicos/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ribonucleases/metabolismo , Fatores Sexuais , Testosterona/farmacologia , Fatores de Tempo , Regulação para CimaRESUMO
Characteristic of both chronic wounds and acute wounds that fail to heal are excessive leukocytosis and reduced matrix deposition. Estrogen is a major regulator of wound repair that can reverse age-related impaired wound healing in human and animal models, characterized by a dampened inflammatory response and increased matrix deposited at the wound site. Macrophage migration inhibitory factor (MIF) is a candidate proinflammatory cytokine involved in the hormonal regulation of inflammation. We demonstrate that MIF is upregulated in a distinct spatial and temporal pattern during wound healing and its expression is markedly elevated in wounds of estrogen-deficient mice as compared with intact animals. Wound-healing studies in mice rendered null for the MIF gene have demonstrated that in the absence of MIF, the excessive inflammation and delayed-healing phenotype associated with reduced estrogen is reversed. Moreover, in vitro assays have shown a striking estrogen-mediated decrease in MIF production by activated murine macrophages, a process involving the estrogen receptor. We suggest that estrogen inhibits the local inflammatory response by downregulating MIF, suggesting a specific target for future therapeutic intervention in impaired wound-healing states.
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Regulação para Baixo/fisiologia , Estrogênios/metabolismo , Fatores Inibidores da Migração de Macrófagos/metabolismo , Cicatrização/fisiologia , Animais , Células Epidérmicas , Epiderme/metabolismo , Epiderme/patologia , Estrogênios/genética , Feminino , Humanos , Lipopolissacarídeos/farmacologia , Fatores Inibidores da Migração de Macrófagos/genética , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Ovariectomia , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Fator de Crescimento Transformador beta/metabolismoRESUMO
The silico-phosphate mineral perhamite has been studied using a combination of electron and vibrational spectroscopy. SEM photomicrographs reveal that perhamite morphology consists of very thin intergrown platelets that can form a variety of habits. Infrared spectroscopy in the hydroxyl-stretching region shows a number of overlapping bands which are observed in the range 3581-3078 cm(-1). These wavenumbers enable an estimation to be made of the hydrogen bond distances in perhamite: 3.176(0), 2.880(5), 2.779(6), 2.749(3), 2.668(1) and 2.599(7)A. Intense Raman bands are observed in the region 1110-1130 and 966-996 cm(-1) and are assigned to the SiO(4) and PO(4) symmetric stretching modes. Other bands are observed in the range 1005-1096 cm(-1) and are attributed to the nu(3) antisymmetric bending modes of PO(4). Some low intensity bands around 874 cm(-1) were discovered and remain unclassified. Bands in the low-wavenumber region are assigned to the nu(4) and nu(2) out-of-plane bending modes of the OSiO and PO(4) units. Raman spectroscopy is a useful tool in determining the vibrational spectroscopy of mixed hydrated multi-anion minerals such as perhamite. Information on such a mineral would be difficult to obtain by other means.
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Minerais/análise , Fosfatos/análise , Silicatos/análise , Espectrofotometria Infravermelho/métodos , Análise Espectral Raman/métodos , Cristalografia por Raios X , Microscopia Eletrônica de Varredura , Minerais/química , Modelos Químicos , Fosfatos/química , Silicatos/química , Água/químicaRESUMO
A new superstructure of the mineral camerolaite, Cu6Al3(OH)18(H2O)2[Sb(OH)6](SO4), has been refined in space group P\bar 1 with unit-cell parameters aP = 7.7660â (16), bP = 8.759â (4), cP = 11.306â (2)â Å, αP = 108.67â (4), ßP = 83.41â (3), γP = 126.64â (2)°, V = 581.6â (3) Å3 and Z = 1, with R1 = 0.0951 (all data). This is the first refined example of a cyanotrichite-group mineral in which long-range order of interlayer anions produces a superstructure along b, although diffuse scattering has previously been reported that corresponds to short-range order. Though the structure shares with other members of the cyanotrichite group a structural unit in which ribbons of edge-sharing Cu and Al octahedra form layers || (001), the superstructure arises from regular alternation of [SO4] and [Sb(OH)6] polyhedra along rods that lie between the layers, and phase coupling between rods that maximizes the distance between [SO4] groups of adjacent rods along a and c directions. This arrangement suggests an alternative nearly orthogonal choice of unit cell in F\bar 1 with parameters aF = 12.473â (26), bF = 8.759â (4), cF = 21.476â (7) Å, αF = 85.94â (4), ßF = 95.91â (5), γF = 92.34â (9)°, which is recommended for comparing this structural variety of camerolaite with other members of the group.
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Culture surfaces that substantially reduce the degree of cell manipulation in the delivery of cell sheets to patients are described. These surfaces support the attachment, culture, and delivery of multipotent adult progenitor cells (MAPC). It was essential that the processes of attachment/detachment to the surface did not affect cell phenotype nor the function of the cultured cells. Both acid-based and amine-based surface coatings were generated from acrylic acid, propanoic acid, diaminopropane, and heptylamine precursors, respectively. While both functional groups supported cell attachment/detachment, amine coated surfaces gave optimal performance. X-ray photoelectron spectroscopy (XPS) showed that at a primary amine to carbon surface ratio of between 0.01 and 0.02, greater than 90% of attached cells were effectively transferred to a model wound bed. A dependence on primary amine concentration has not previously been reported. After 48 h of culture on the optimized amine surface, PCR, functional, and viability assays showed that MAPC retained their stem cell phenotype, full metabolic activity, and biological function. Consequently, in a proof of concept experiment, it was shown that this amine surface when coated onto a surgical dressing provides an effective and simple technology for the delivery of MAPC to murine dorsal excisional wounds, with MAPC delivery verified histologically. By optimizing for cell delivery using a combination of in vitro and in vivo techniques, we developed an effective surface for the delivery of MAPC in a clinically relevant format.
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Células-Tronco , Células-Tronco Adultas , Animais , Bandagens , Células Cultivadas , Humanos , Camundongos , Células-Tronco MultipotentesRESUMO
A new hydrated yttrium copper tellurite nitrate, yttrium(III) copper(II) bis-[trioxidotellurate(IV)] nitrate trihydrate, has been synthesized hydro-thermally in a Teflon-lined autoclave and structurally determined using synchrotron radiation. The new phase is the first example containing yttrium, copper and tellurium in one structure. Its crystal structure is unique, with relatively strongly bound layers extending parallel to (020), defined by YO8, CuO4 and TeO3 polyhedra, while the NO3 (-) anions and one third of the water mol-ecules lie between those layers. The structural unit consists of [Cu2(TeO3)4](4-) loop-branched chains of {Cuâ¯Teâ¯Cuâ¯Te} squares running parallel to [001], which are linked further into layers only through Y(O,H2O)8 polyhedra. Weak 'secondary' Te bonds and O-Hâ¯O hydrogen-bonding inter-actions, involving water mol-ecules and layer O atoms, link the layers and inter-layer species. IR spectroscopic data are also presented.