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1.
Cell Tissue Res ; 391(1): 173-188, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36271300

RESUMO

Safety concerns associated with foetal bovine serum (FBS) have restricted its translation into clinics. We hypothesised that platelet lysate (PL) can be utilised as a safe alternative to produce serum-free 3D-engineered skin. PL supported a short-term expansion of fibroblasts, with negligible replication-induced senescence and directed epidermal stratification. PL-expanded fibroblasts were phenotypically separated into three subpopulations of CD90+FAP+, CD90+FAP- and CD90-FAP+, based on CD90 (reticular marker) and FAP (papillary marker) expression profile. PL drove the expansion of the intermediate CD90+ FAP+ subpopulation in expense of reticular CD90+FAP-, which may be less fibrotic once grafted. The 3D-engineered skin cultured in PL was analysed by immunofluorescence using specific markers. Detection of ColIV and LMN-511 confirmed basement membrane. K10 confirmed near native differentiation pattern of neo-epidermis. CD29- and K5-positive interfollicular stem cells were also sustained. Transmission and scanning electron microscopies detailed the ultrastructure of the neo-dermis and neo-epidermis. To elucidate the underlying mechanism of the effect of PL on skin maturation, growth factor contents in PL were measured, and TGF-ß1 was identified as one of the most abundant. TGF-ß1 neutralising antibody reduced the number of Ki67-positive proliferative cells, suggesting TGF-ß1 plays a role in skin maturation. Moreover, the 3D-engineered skin was exposed to lucifer yellow on days 1, 3 and 5. Penetration of lucifer yellow into the skin was used as a semi-quantitative measure of improved barrier function over time. Our findings support the concept of PL as a safe and effective serum alternative for bioengineering skin for cell therapies.


Assuntos
Extratos Celulares , Pele , Engenharia Tecidual , Plaquetas/química , Diferenciação Celular , Epiderme , Fibroblastos , Pele/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Extratos Celulares/química , Engenharia Tecidual/métodos
2.
Acta Biomater ; 136: 199-209, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34587524

RESUMO

Platelets are a reservoir of growth factors, cytokines and chemokines involved in spontaneous wound repair. In this study, a platelet-rich and fibrin-rich hydrogel was generated from expired platelet components that would have otherwise been transfused. The material contained physiological concentrations of transforming growth factor ß1 (TGF-ß1, platelet-derived growth factor AB (PDGF-AB), PDGF-BB, insulin-like growth factor-1 (IGF-1), fibroblast growth factor 2 (FGF-2), and epidermal growth factor (EGF). The effect of the hydrogel on wound repair was investigated in SKH-1 mice. Full thickness dorsal wounds were created on the mice and treated with the hydrogel at various concentrations. Immunohistochemical staining with CD31 (endothelial cell marker) revealed that wounds treated with the hydrogel showed significantly enhanced vascularisation in the wound bed. Moreover, high levels of interleukin-6 (IL-6) and KC (IL-8 functional homologue) in treated wounds were sustained over a longer period of time, compared to untreated wounds. We postulate that sustained IL-6 is a driver, at least partly, of enhanced vascularisation in full thickness wounds treated with the hydrogel. Future work is needed to explore whether this hydrogel can be utilised as a treatment option when vascularisation is a critical limitation. STATEMENT OF SIGNIFICANCE: The economic cost of wound repair is estimated in billions of dollars each year. In many cases time required to vascularise wounds is a major contributor to slow wound repair. In this study, we developed a blood-derived platelet- and fibrin-rich hydrogel. It contains a number of growth factors actively involved in spontaneous wound healing. This hydrogel significantly improved dermal repair and vascularisation in a full-thickness wound mouse model. This study provides an action mechanism for modulation of localised inflammation.


Assuntos
Plaquetas , Hidrogéis , Animais , Becaplermina , Fator de Crescimento Epidérmico , Hidrogéis/farmacologia , Camundongos , Cicatrização
3.
Spine Deform ; 9(6): 1651-1657, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34228311

RESUMO

PURPOSE: Intracanal rib head penetration is a well-known entity in dystrophic scoliotic curves in neurofibromatosis type 1. There is potential for spinal cord injury if this is not recognised and managed appropriately. No current CT-based classification system is currently in use to quantify rib head penetration. This article aims to propose and evaluate a novel CT-based classification for rib head penetration primarily for neurofibromatosis but which can also be utilised in other conditions of rib head penetration. MATERIALS AND METHODS: The grading was developed as four grades: normal rib head (RH) position-Grade 0, subluxed extracanal RH position-Grade 1, RH at pedicle-Grade 2, intracanal RH-Grade 3. Grade 3 was further classified depending on the head position in the canal divided into thirds. Rib head penetration into proximal third (from ipsilateral side)-Grade 3A, into the middle third-Grade 3B and into the distal third-Grade 3C. Seventy-five axial CT images of Neurofibromatosis Type 1 patients in the paediatric age group were reviewed by a radiologist and a spinal surgeon independently to assess interobserver and intraobserver agreement of the novel CT classification. Agreement analysis was performed using the weighted Kappa statistic. RESULTS: There was substantial interobserver correlation with mean Kappa score (k = 0.8, 95% CI 0.7-0.9) and near perfect intraobserver Kappa of 1.0 (95% CI 0.9-1.0) and 0.9 (95% CI 0.9-1.0) for the two readers. CONCLUSION: The novel CT-based classification quantifies rib head penetration which aids in management planning.


Assuntos
Neurofibromatose 1 , Escoliose , Criança , Humanos , Costelas/diagnóstico por imagem , Coluna Vertebral , Tomografia Computadorizada por Raios X
6.
Clin Transl Oncol ; 20(11): 1474-1483, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29736694

RESUMO

INTRODUCTION: The PI3K/AKT/mTOR pathway is an oncogenic driver in breast cancer (BC). In this multi-center, pre-surgical study, we evaluated the tissue effects of the AKT inhibitor MK-2206 in women with stage I-III BC. MATERIALS AND METHODS: Two doses of weekly oral MK2206 were administered at days - 9 and - 2 before surgery. The primary endpoint was reduction of pAktSer473 in breast tumor tissue from diagnostic biopsy to surgery. Secondary endpoints included changes in PI3K/AKT pathway tumor markers, tumor proliferation (ki-67), insulin growth factor pathway blood markers, pharmacokinetics (PK), genomics, and MK-2206 tolerability. Paired t tests were used to compare biomarker changes in pre- and post-MK-2206, and two-sample t tests to compare with prospectively accrued untreated controls. RESULTS: Despite dose reductions, the trial was discontinued after 12 patients due to grade III rash, mucositis, and pruritus. While there was a trend to reduction in pAKT after MK-2206 (p = 0.06), there was no significant change compared to controls (n = 5, p = 0.65). After MK-2206, no significant changes in ki-67, pS6, PTEN, or stathmin were observed. There was no significant association between dose level and PK (p = 0.11). Compared to controls, MK-2206 significantly increased serum glucose (p = 0.02), insulin (p < 0.01), C-peptide (p < 0.01), and a trend in IGFBP-3 (p = 0.06). CONCLUSION: While a trend to pAKT reduction after MK-2206 was observed, there was no significant change compared to controls. However, the accrued population was limited, due to toxicity being greater than expected. Pre-surgical trials can identify in vivo activity in the early drug development, but side effects must be considered in this healthy population.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Carcinoma Ductal de Mama/tratamento farmacológico , Compostos Heterocíclicos com 3 Anéis/uso terapêutico , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Adulto , Idoso , Biomarcadores/sangue , Biomarcadores/metabolismo , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/cirurgia , Avaliação de Medicamentos , Feminino , Compostos Heterocíclicos com 3 Anéis/efeitos adversos , Compostos Heterocíclicos com 3 Anéis/farmacologia , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , New York , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos
7.
Vox Sang ; 2018 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-29633290

RESUMO

BACKGROUND AND OBJECTIVES: Cold-stored platelets may be an alternative to conventional room temperature (RT) storage. However, cold-stored platelets are cleared more rapidly from circulation, reducing their suitability for prophylactic transfusion. To minimise wastage, it may be beneficial to store platelets conventionally until near expiry (4 days) for prophylactic use, transferring them to refrigerated storage to facilitate an extended shelf life, reserving the platelets for the treatment of acute bleeding. MATERIALS AND METHODS: Two ABO-matched buffy-coat-derived platelets (30% plasma/70% SSP+) were pooled and split to produce matched pairs (n = 8 pairs). One unit was stored at 2-6°C without agitation (day 1 postcollection; cold); the second unit was stored at 20-24°C with constant agitation until day 4 then stored at 2-6°C thereafter (delayed-cold). All units were tested for in vitro quality periodically over 21 days. RESULTS: During storage, cold and delayed-cold platelets maintained a similar platelet count. While pH and HSR were significantly higher in delayed-cold platelets, other metabolic markers, including lactate production and glucose consumption, did not differ significantly. Furthermore, surface expression of phosphatidylserine and CD62P, release of soluble CD62P and microparticles were not significantly different, suggesting similar activation profiles. Aggregation responses of delayed-cold platelets followed the same trend as cold platelets once transferred to cold storage, gradually declining over the storage period. CONCLUSION: The metabolic and activation profile of delayed-cold platelets was similar to cold-stored platelets. These data suggest that transferring platelets to refrigerated storage when near expiry may be a viable option for maximising platelet inventories.

8.
Vox Sang ; 113(4): 317-328, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29441601

RESUMO

Conventional storage of platelet concentrates limits their shelf life to between 5 and 7 days due to the risk of bacterial proliferation and the development of the platelet storage lesion. Cold storage and cryopreservation of platelets may facilitate extension of the shelf life to weeks and years, and may also provide the benefit of being more haemostatically effective than conventionally stored platelets. Further, treatment of platelet concentrates with pathogen inactivation systems reduces bacterial contamination and provides a safeguard against the risk of emerging and re-emerging pathogens. While each of these alternative storage techniques is gaining traction individually, little work has been done to examine the effect of combining treatments in an effort to further improve product safety and minimize wastage. This review aims to discuss the benefits of alternative storage techniques and how they may be combined to alleviate the problems associated with conventional platelet storage.


Assuntos
Plaquetas/efeitos dos fármacos , Preservação de Sangue/métodos , Criopreservação/métodos , Refrigeração/métodos , Anti-Infecciosos/farmacologia , Preservação de Sangue/efeitos adversos , Humanos
9.
Child Neuropsychol ; 24(4): 427-450, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-28277151

RESUMO

The present study examines the potential of sequencing a neurocognitive intervention with behavioral parent training (BPT) to improve executive functions (EFs), psychiatric symptoms, and multiple indices of functional impairment in school-age children aged 7 to 11 years who have been diagnosed with attention-deficit/hyperactivity disorder (ADHD). Specifically, in a randomized controlled trial design, 85 children were assigned to either Cogmed Working Memory Training (CWMT) followed by an empirically supported, manualized BPT intervention, or to a placebo version of CWMT followed by the same BPT intervention. Working memory maintenance (i.e., attention control/short-term memory), working memory processing and manipulation, ADHD and oppositional defiant disorder (ODD) symptoms, impairment in parent-child dynamics, familial impairment, and overall functional compromise were evaluated as outcomes. The results suggest specific effects of the combined CWMT and BPT program on verbal and nonverbal working memory storage and nonverbal working memory processing and manipulation but no incremental benefits in regard to ADHD symptoms, ODD symptoms, and functional outcomes. The present findings do not support the hypothesis regarding the complementary and augmentative benefits of sequenced neurocognitive and BPT interventions for the treatment of ADHD. These results, the study's limitations, and future directions for research are further discussed.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/terapia , Terapia Comportamental/métodos , Pais/psicologia , Transtorno do Deficit de Atenção com Hiperatividade/patologia , Criança , Feminino , Humanos , Masculino
10.
Transfus Med ; 28(3): 243-248, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28833874

RESUMO

OBJECTIVES: To establish the current use of granulocyte transfusions in haematology patients and explore interest in further research. BACKGROUND: Granulocytes may be used for the treatment of severe infection in neutropenic patients or for primary or secondary prophylaxis. Clinical utility of granulocyte transfusions is unclear, and recent studies have demonstrated equivocal outcomes. Pooled granulocytes are the main granulocyte product used in England and Wales, but there are no data on the patterns of use and little consensus on accepted indications. METHODS: A survey was distributed to UK hospitals delivering intensive chemotherapy. Clinical scenarios were posed, with further questions on clinician experience of using granulocytes, availability of the product, barriers to use and interest in further research. RESULTS: The response rate was 57%; 34·9% of all responses were from allogeneic stem cell transplant centres. Paediatric centres comprised 9·5% respondents, and 19% centres had access to apheresis granulocytes. Of respondents, 58·7% had used granulocytes in the last 3 years, 89·2% of whom used granulocytes to treat refractory infection. There was little consensus on use of granulocytes in the given clinical scenarios even when patients clearly met national guideline criteria. Paediatric centres were overall more likely to recommend granulocyte use. The most frequently identified barrier to use of granulocytes was lack of evidence of effect. Of the respondents, 75% indicated a willingness to participate in further research. CONCLUSION: There remains a lack of consistency about use of granulocytes, which is unsurprising given the lack of clinical data to support their efficacy. We did, however, demonstrate a willingness to participate in further research.


Assuntos
Granulócitos , Transfusão de Leucócitos , Neutropenia/epidemiologia , Neutropenia/terapia , Inglaterra/epidemiologia , Feminino , Humanos , Masculino , País de Gales/epidemiologia
17.
Vox Sang ; 112(4): 310-317, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28332214

RESUMO

BACKGROUND: Serum eye drops (SEDs) are used to treat dry eye syndrome and non-healing corneal lesions when other treatments fail. Despite many clinical studies demonstrating the efficacy of both autologous and allogeneic SEDs, there is no internationally harmonized method for producing SEDs. MATERIALS AND METHODS: A 40-question survey requesting information regarding donor selection, blood collection and processing, infectious disease screening, shelf life and regulatory requirements for the production of autologous and allogeneic SEDs was developed by the Biomedical Excellence for Safer Transfusion Collaborative. Survey data were collected into a database via a secure web interface and then downloaded into Excel for further analysis. RESULTS: A total of 55 responses were received, with 21 responses from centres indicating they produce SEDs. Based on the responses, collection and processing practices differ widely, according to the size of the centre making the SEDs, and their ability to collect, process and test the blood. CONCLUSION: Despite divergences in the methods for producing SEDs, the end result is a small-volume aliquot of serum that can be administered by a patient at home. If more centres move from producing autologous to allogeneic SEDs, this may provide an opportunity for production methods to become more standardized internationally.


Assuntos
Síndromes do Olho Seco/tratamento farmacológico , Soluções Oftálmicas/uso terapêutico , Soro , Tecnologia Farmacêutica/métodos , Coleta de Amostras Sanguíneas , Seleção do Doador , Feminino , Humanos , Masculino , Segurança do Paciente , Inquéritos e Questionários , Tecnologia Farmacêutica/normas
18.
Sci Rep ; 7: 42650, 2017 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-28218254

RESUMO

We demonstrate a low-profile holographic imaging system at millimeter wavelengths based on an aperture composed of frequency-diverse metasurfaces. Utilizing measurements of spatially-diverse field patterns, diffraction-limited images of human-sized subjects are reconstructed. The system is driven by a single microwave source swept over a band of frequencies (17.5-26.5 GHz) and switched between a collection of transmit and receive metasurface panels. High fidelity image reconstruction requires a precise model for each field pattern generated by the aperture, as well as the manner in which the field scatters from objects in the scene. This constraint makes scaling of computational imaging systems inherently challenging for electrically large, coherent apertures. To meet the demanding requirements, we introduce computational methods and calibration approaches that enable rapid and accurate imaging performance.


Assuntos
Holografia , Micro-Ondas , Radiação , Humanos , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional
19.
Bone Marrow Transplant ; 52(5): 717-725, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28092349

RESUMO

Improving haematopoietic cell transplantation outcomes by selection of an HLA-matched unrelated donor is best practice; however, donor selection by secondary characteristics is controversial. We studied 1271 recipients with haematological malignancies who underwent T-cell-depleted allografts and had complete data on HLA-matching status for six loci (HLA-A, -B, -C, -DRB1, -DQB1, -DPB1) and clinical outcome data. Five-year overall survival was 40.6%. HLA mismatching (at HLA-A, -B, -C, -DRB1, -DQB1) relative risk (RR) 1.22, 95% confidence interval (CI) 1.2-1.5, P=0.033 for 1 mismatch and RR 1.46, 95% CI 1.1-1.9, P=0.009 for >1 mismatch) and CMV mismatching (RR 1.37, 95% CI 1.2-1.6, P<0.001) were significantly associated with inferior survival. Donors aged <30 years showed a trend towards better survival. The multivariate model for mortality, combining CMV and HLA-match status, found an RR of 1.36 (95% CI 1.1-1.7, P=0.003) for HLA matched/CMV mismatched, an RR of 1.22 (95% CI 0.99-1.5, P=0.062) for HLA mismatched/CMV matched and an RR of 1.81 (95% CI 1.4-2.3, P=<0.001) for HLA/ CMV mismatched, compared with the HLA/CMV-matched recipients. These data suggest that HLA and CMV matching status should be considered when selecting unrelated donors and that CMV matching may abrogate the effect of an HLA mismatch.


Assuntos
Citomegalovirus/imunologia , Antígenos HLA/imunologia , Neoplasias Hematológicas/terapia , Transplante de Células-Tronco Hematopoéticas/métodos , Doadores não Relacionados/provisão & distribuição , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Histocompatibilidade , Humanos , Depleção Linfocítica , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Testes Sorológicos , Análise de Sobrevida , Adulto Jovem
20.
Leukemia ; 31(1): 58-64, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27480385

RESUMO

Safety and efficacy data on pegylated asparaginase (PEG-ASP) in adult acute lymphoblastic leukaemia (ALL) induction regimens are limited. The UK National Cancer Research Institute UKALL14 trial NCT01085617 prospectively evaluated the tolerability of 1000 IU/m2 PEG-ASP administered on days 4 and 18 as part of a five-drug induction regimen in adults aged 25-65 years with de novo ALL. Median age was 46.5 years. Sixteen of the 90 patients (median age 56 years) suffered treatment-related mortality during initial induction therapy. Eight of the 16 died of sepsis in combination with hepatotoxicity. Age and Philadelphia (Ph) status were independent variables predicting induction death >40 versus ⩽40 years, odds ratio (OR) 18.5 (2.02-169.0), P=0.01; Ph- versus Ph+ disease, OR 13.60 (3.52-52.36), P<0.001. Of the 74 patients who did not die, 37 (50.0%) experienced at least one grade 3/4 PEG-ASP-related adverse event, most commonly hepatotoxicity (36.5%, n=27). A single dose of PEG-ASP achieved trough therapeutic enzyme levels in 42/49 (86%) of the patients tested. Although PEG-ASP delivered prolonged asparaginase activity in adults, it was difficult to administer safely as part of the UKALL14 intensive multiagent regimen to those aged >40 years. It proved extremely toxic in patients with Ph+ ALL, possibly owing to interaction with imatinib.


Assuntos
Asparaginase/toxicidade , Polietilenoglicóis/toxicidade , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Adulto , Fatores Etários , Idoso , Antineoplásicos/administração & dosagem , Antineoplásicos/toxicidade , Asparaginase/administração & dosagem , Asparaginase/farmacocinética , Doença Hepática Induzida por Substâncias e Drogas/mortalidade , Humanos , Quimioterapia de Indução/métodos , Pessoa de Meia-Idade , Cromossomo Filadélfia , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/farmacocinética , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Sepse/induzido quimicamente , Sepse/mortalidade
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