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1.
J Neurointerv Surg ; 16(2): 192-196, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-37019626

RESUMO

Epistaxis is common, impacting more than half the population, and can require procedural intervention in approximately 10% of cases. With an aging population and increasing use of antiplatelets and anticoagulants, severe epistaxis is likely to increase in frequency significantly over the next two decades. Sphenopalatine artery embolization is rapidly becoming the most common type of procedural intervention. The efficacy of endovascular embolization is dependent on a refined understanding of the anatomy and collateral physiology of this circulation as well as the impact of temporizing measures such as nasal packing and inflation of a nasal balloon. Likewise, safety is dependent on a detailed appreciation of collateralization with the internal carotid artery and ophthalmic artery. Cone beam CT imaging has the resolution to enable a clear visualization of the anatomy and collateral circulation associated with the arterial supply to the nasal cavity, in addition to assisting with hemorrhage localization. We present a review of epistaxis treatment, a detailed description of anatomic and physiologic considerations informed by cone beam CT imaging, and a proposed protocol for sphenopalatine embolization for which there is currently no standard.


Assuntos
Embolização Terapêutica , Epistaxe , Humanos , Idoso , Epistaxe/diagnóstico por imagem , Epistaxe/terapia , Resultado do Tratamento , Embolização Terapêutica/métodos , Artérias , Tomografia Computadorizada de Feixe Cônico
2.
Regen Med ; 18(4): 301-311, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36891911

RESUMO

Aim: To explore prospective donors' attitudes and perceptions toward donating hematopoietic stem cells (HSCs) for novel treatments research and development (R&D). Methods: A survey was launched by Anthony Nolan (AN) to assess prospective donors' willingness to donate HSCs for novel therapies R&D, and their degree of comfort with the AN collaborating with and receiving payment from external organizations. Results: Most participants (87%) were willing to donate for novel treatment R&D and were comfortable with AN collaborating with external organizations and receiving payment (91% and 80%, respectively). Conclusion: Results reveal an overall positive response toward donating HSCs for R&D. These findings can support stakeholders and policymakers in outlining donation practices that uphold donors' safety and welfare.


Recent interest in the development of cell-based novel treatments using stem cells from healthy donors as opposed to patients' own stem cells may place pressure on stem cell donor registries to adapt and provide donor stem cells to the cell and gene industry. Since stem cell donor registries were originally established to connect patients in need of stem cell transplantation with matched willing stem cell donors, this shift in practice might result in several implications. Therefore, Anthony Nolan (AN), an unrelated stem cell donor registry in the UK, launched a survey to explore the willingness of potential donors to donate stem cells for novel treatment research and development (R&D). The results show that most participants (87%) would be willing to donate stem cells for novel treatment research and development. Most participants were comfortable with AN collaborating with external organizations (91%) and receiving payment from these organizations (80%). Additionally, some participants provided written responses that explained their answers to the questions in the survey. While some participants had positive views on collaborations with external establishments, others had apprehensions over their donations leading to profiteering. Moreover, participants had concerns over their privacy, especially if external collaborations with pharmaceutical companies were to take place. Informed consent and transparency over the nature of collaborations could relieve some of the above-mentioned concerns. These findings can support stakeholders and policymakers in outlining donation practices that uphold donors' safety and welfare.


Assuntos
Pesquisa , Doadores de Tecidos , Humanos , Inquéritos e Questionários
3.
J Neurointerv Surg ; 15(8): 766-770, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36180207

RESUMO

BACKGROUND: Cerebral aneurysm rupture is associated with high rates of morbidity and mortality. Detecting aneurysms at high risk of rupture is critical in management decision making. Rupture risk has traditionally been associated with size-measured as a maximum dimension. However, aneurysms are morphologically dynamic, a characteristic ignored by large prospective aneurysm risk studies. Manual measurement is challenging and fraught with error. We used an artificial intelligence (AI) measurement tool to study aneurysms that ruptured during conservative management to detect changes in size not appreciated by manual linear measurement. METHODS: A single practice database with >5000 aneurysms was queried. Patients followed conservatively for an unruptured aneurysm were identified using appropriate diagnosis codes. This cohort was screened for subsequent rupture using procedure codes. Only patients with two vascular imaging studies before rupture were included. RESULTS: Five patients met the criteria. All patients had aneurysm enlargement, two of which were not detected from manual linear measurements, including adjudication and analysis, during a multidisciplinary neurovascular conference in a high volume practice. Maximum dimension increased at a minimum of 1.8% (range 1.8-63.3%) from the first scan to the last, and aneurysm volume increased at a minimum of 5.9% (5.9-385.5%), highlighting the importance of volumetric measurement. CONCLUSIONS: AI-enabled volumetric measurements are more sensitive to changes in size and detected enlargement in all aneurysms that ruptured during conservative management. This finding has major implications for clinical practice and methods used for interval aneurysm measurement in patients being conservatively followed.


Assuntos
Falso Aneurisma , Aneurisma Roto , Aneurisma Intracraniano , Humanos , Estudos Prospectivos , Inteligência Artificial , Tratamento Conservador , Aneurisma Roto/diagnóstico por imagem , Aneurisma Roto/terapia , Aneurisma Roto/complicações , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/terapia , Aneurisma Intracraniano/complicações , Fatores de Risco
4.
Bone Marrow Transplant ; 57(10): 1531-1538, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35804055

RESUMO

Cryopreservation was recommended to ensure continuity in allogeneic hematopoietic progenitor cells (HPC) transplantation during the COVID-19 pandemic. Several groups have shown no impact on clinical outcomes for patients who underwent HPC transplantation with cryopreserved products during the first months of this pandemic. However, concerns about quality control attributes after cryopreservation have been raised. We investigated, in 155 allogeneic peripheral blood cryopreserved HPC, leukocytapheresis characteristics influencing viable CD34+ and CD3+ cells, and CFU-GM recoveries after thawing. Collection characteristics such as volume, nucleated cells (NC)/mL and hematocrit correlated with viable CD34+ and CD3+ cells recoveries after thawing in univariate analysis but only CD3+ cells remained statistically significant in multivariate analysis (r2 = 0.376; P = < 0.001). Additionally, transit time also showed correlation with viable CD34+ (r2 = 0.186), CD3+ (r2 = 0.376) and CFU-GM recoveries (r2 = 0.212) in multivariate analysis. Thus, diluting leukocytapheresis below 200 × 106 NC/mL, avoiding red cells contamination above 2%, cryopreserving below 250 × 106 NC/mL and minimizing transit time below 36 h, prevented poor viable CD34+ and CD3+ cells, and CFU-GM recoveries. In summary, optimizing leukocytapheresis practices and minimizing transportation time may better preserve the quality attributes of HPC when cryopreservation is indicated.


Assuntos
COVID-19 , Transplante de Células-Tronco Hematopoéticas , Antígenos CD34/análise , Sobrevivência Celular , Criopreservação , Células-Tronco Hematopoéticas , Humanos , Leucaférese , Pandemias
5.
Cytotherapy ; 24(10): 1060-1066, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35654716

RESUMO

BACKGROUND AIMS: In this study, the authors sought to assess whether cord blood units (CBUs) collected from donors of non-European ethnic backgrounds are utilized for umbilical cord blood transplantation (UCBT) at a different rate than those of European ethnic backgrounds. The authors also examined potential methods of enriching these under-represented ethnic backgrounds in cord blood bank (CBB) inventories without increasing financial overheads and without compromising total inventory utilization or post-transplant outcomes. METHODS: Data from N = 6506 searchable or shipped Anthony Nolan Cell Therapy Centre grafts were used in this study. Banked grafts were graded from A+ to D based on total nucleated cell and CD34+ cell content. Utilizations of each grade group were further stratified by graft ethnic background. The Mantel-Cox log-rank test was performed in conjunction with Kaplan-Meier survival analysis to compare utilization rates and post-transplant outcomes. For shipped grafts, levels of HLA matching at HLA-A, HLA-B and HLA-DR loci were also analyzed by graft ethnic background and grade using data from the Eurocord/EBMT registry. RESULTS: Overall utilization of non-European grafts did not significantly differ from that of European grafts (2.5% versus 2.2%, P = 0.23). However, significant differences were found when stratifying utilization rates by cell content. The probability of non-European D grade grafts being utilized was 3-fold higher than that of European D grade grafts (1.1% versus 0.4%, P = 0.03) and comparable to that of European C grade grafts (1.1% versus 0.9%, P = 0.90). No significant differences were found between D and C grade grafts in terms of overall survival (OS) (P = 0.12), in part due to a disproportionate utilization of D grade grafts for pediatric UCBT (74% versus 39%, age difference P < 0.001). Furthermore, non-European graft shipments were 4-fold less likely to be a 6/6 HLA match to their recipients relative to European graft shipments (7% versus 29%). CONCLUSIONS: The authors have identified a niche for CBUs of low cell content collected from donors of non-European ethnic backgrounds that has been overlooked by previous studies. Banking of these CBUs for pediatric UCBT instead of CBUs from European donors containing modestly higher cell content is an ethical approach to increasing the ethnic diversity of CBB inventory-and, consequently, the probability of non-European recipients finding a 6/6 HLA-matched graft-without compromising post-transplant OS or overall rate of inventory utilization.


Assuntos
Transplante de Células-Tronco de Sangue do Cordão Umbilical , Doença Enxerto-Hospedeiro , Bancos de Sangue , Criança , Etnicidade , Sangue Fetal , Sobrevivência de Enxerto , Humanos , Doadores de Tecidos
6.
Ann Neurol ; 92(3): 364-378, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35599458

RESUMO

OBJECTIVE: This study was undertaken to evaluate functional and safety outcomes for endovascular thrombectomy (EVT) versus medical management (MM) in patients with large vessel occlusion (LVO) and mild neurological deficits, stratified by perfusion imaging mismatch. METHODS: The pooled cohort consisted of patients with National Institutes of Health Stroke Scale (NIHSS) < 6 and internal carotid artery (ICA), M1, or M2 occlusions from the Extending the Time for Thrombolysis in Emergecy Neurological Deficits - Intra-Arterial (EXTEND-IA) Trial,  Tenecteplase vs Alteplase before Endovascular Thrombectomy in Ischemic Stroke (EXTEND-IA TNK) trials Part I/II and prospective data from 15 EVT centers from October 2010 to April 2020. RAPID software estimated ischemic core and mismatch. Patients receiving primary EVT (EVTpri ) were compared to those who received primary MM (MMpri ), including those who deteriorated and received rescue EVT, in overall and propensity score (PS)-matched cohorts. Patients were stratified by target mismatch (mismatch ratio ≥ 1.8 and mismatch volume ≥ 15ml). Primary outcome was functional independence (90-day modified Rankin Scale = 0-2). Secondary outcomes included safety (symptomatic intracerebral hemorrhage [sICH], neurological worsening, and mortality). RESULTS: Of 540 patients, 286 (53%) received EVTpri and demonstrated larger critically hypoperfused tissue (Tmax > 6 seconds) volumes (median [IQR]: 64 [26-96] ml vs MMpri : 40 [14-76] ml, p < 0.001) and higher presentation NIHSS (median [IQR]: 4 [2-5] vs MMpri : 3 [2-4], p < 0.001). Functional independence was similar (EVTpri : 77.4% vs MMpri : 75.6%, adjusted odds ratio [aOR] = 1.29, 95% confidence interval [CI] = 0.82-2.03, p = 0.27). EVT had worse safety regarding sICH (EVTpri : 16.3% vs MMpri : 1.3%, p < 0.001) and neurological worsening (EVTpri : 19.6% vs MMpri : 6.7%, p < 0.001). In 414 subjects (76.7%) with target mismatch, EVT was associated with improved functional independence (EVTpri : 77.4% vs MMpri : 72.7%, aOR = 1.68, 95% CI = 1.01-2.81, p = 0.048), whereas there was a trend toward less favorable outcomes with primary EVT (EVTpri : 77.4% vs MMpri : 83.3%, aOR = 0.39, 95% CI = 0.12-1.34, p = 0.13) without target mismatch (pinteraction  = 0.06). Similar findings were observed in a propensity score-matched subpopulation. INTERPRETATION: Overall, EVT was not associated with improved clinical outcomes in mild strokes due to LVO, and sICH was increased. However, in patients with target mismatch profile, EVT was associated with increased functional independence. Perfusion imaging may be helpful to select mild stroke patients for EVT. ANN NEUROL 2022;92:364-378.


Assuntos
Isquemia Encefálica , Procedimentos Endovasculares , Acidente Vascular Cerebral , Isquemia Encefálica/cirurgia , Hemorragia Cerebral , Procedimentos Endovasculares/métodos , Humanos , Estudos Prospectivos , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/cirurgia , Trombectomia/métodos , Resultado do Tratamento
7.
Vet Pathol ; 58(4): 663-673, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33813951

RESUMO

In psittacine birds, round cell neoplasms that originate from lymphocytes, plasma cells, histiocytes, or mast cells are sporadic and poorly described. The lack of morphological and immunohistochemical diagnostic criteria or grading schemes make specific diagnoses and prognoses challenging. We assessed cases of psittacine birds diagnosed with round cell neoplasia from 3 North American veterinary diagnostic laboratories to describe the diagnostic features of these tumors. For all cases, demographic data, anatomic distribution, histological features, and immunoreactivity for T (CD3) and B (Pax5 and MUM-1) cell markers were assessed using tissue microarrays and whole slide mounts. Thirty-eight psittacine birds representing 14 species were included. Tumors were mainly infiltrative and multicentric, were composed of homogenous sheets of round to polygonal cells, and commonly presented with a high mitotic count (average 21 mitoses per high-power field). Based on Pax5 immunoreactivity, B-cell lymphoma was most common (19/38 [50%]), and was significantly associated with involvement of the gastrointestinal and urogenital systems. Of the 38 cases, 6 (16%) were consistent with T-cell lymphoma, 3 (8%) with plasma cell tumor, and 3 (8%) were double-reactive for both B- and T-lymphocyte markers. This is the first study to describe morphologic and immunohistochemical features of round cell neoplasia in a large number of psittacine birds, and provides benchmark data for future studies aimed at elucidating the diagnosis and prognosis of these neoplasms. These data also provide useful information about reactivity of commercially available antibodies as lymphocyte markers in tissues of multiple psittacine species.


Assuntos
Doenças das Aves , Linfoma , Papagaios , Animais , Doenças das Aves/diagnóstico , Linfoma/veterinária
9.
Int J Mol Sci ; 21(19)2020 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-32993167

RESUMO

Kluyveromyces marxianus (K. marxianus) is an increasingly popular industrially relevant yeast. It is known to possess a highly efficient non-homologous end joining (NHEJ) pathway that promotes random integration of non-homologous DNA fragments into its genome. The nature of the integration events was traditionally analyzed by Southern blot hybridization. However, the precise DNA sequence at the insertion sites were not fully explored. We transformed a PCR product of the Saccharomyces cerevisiae URA3 gene (ScURA3) into an uracil auxotroph K. marxianus otherwise wildtype strain and picked 24 stable Ura+ transformants for sequencing analysis. We took advantage of rapid advances in DNA sequencing technologies and developed a method using a combination of Illumina MiSeq and Oxford Nanopore sequencing. This approach enables us to uncover the gross chromosomal rearrangements (GCRs) that are associated with the ScURA3 random integration. Moreover, it will shine a light on understanding DNA repair mechanisms in eukaryotes, which could potentially provide insights for cancer research.


Assuntos
Cromossomos Fúngicos , Kluyveromyces/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Aberrações Cromossômicas , Reparo do DNA por Junção de Extremidades , DNA Fúngico/genética , Sequenciamento por Nanoporos/métodos , Transformação Genética
10.
J Vet Diagn Invest ; 31(5): 719-725, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31423916

RESUMO

Aves polyomavirus 1, psittacine beak and feather disease virus, and psittacid herpesvirus 1 are important pathogens of psittacine birds with the potential to cause substantial morbidity and mortality. Using publically available nucleotide sequences, we developed and validated a triplex real-time PCR (rtPCR) assay to rapidly detect these 3 viruses. The assay had high analytical sensitivity, detecting <6 copies of viral DNA per reaction, and 100% analytical specificity, showing no cross-reactivity with 59 other animal pathogens. Archived formalin-fixed, paraffin-embedded tissues from psittacine birds diagnosed at postmortem as infected with each of the viruses as well as virus-negative birds were used to validate the utility of the assay. Birds were selected for the positive cohort if they showed histologic evidence of infection (i.e., characteristic inclusion bodies in tissues); birds in the negative cohort had final diagnoses unrelated to the pathogens of interest. The triplex rtPCR assay confirmed 98% of histopathology-positive cases, and also identified subclinical infections that were not observed by histologic examination, including coinfections. Birds that tested positive only by rtPCR had significantly higher cycle threshold values compared to those with histologic evidence of infection. Positive, negative, and overall percentage agreements as well as the kappa statistic between the results of the assay and histopathology were high, demonstrating the usefulness of the assay as a tool to confirm disease diagnoses, and to improve detection of subclinical infections.


Assuntos
Doenças das Aves/diagnóstico , Infecções por Vírus de DNA/veterinária , Vírus de DNA/isolamento & purificação , Herpesviridae/isolamento & purificação , Reação em Cadeia da Polimerase Multiplex/veterinária , Psittaciformes/virologia , Alphaherpesvirinae/genética , Alphaherpesvirinae/isolamento & purificação , Animais , Doenças das Aves/virologia , Infecções por Circoviridae/diagnóstico , Infecções por Circoviridae/veterinária , Infecções por Circoviridae/virologia , Circovirus/genética , Circovirus/isolamento & purificação , Infecções por Vírus de DNA/diagnóstico , Infecções por Vírus de DNA/virologia , Vírus de DNA/genética , DNA Viral , Herpesviridae/genética , Papagaios/virologia , Polyomaviridae/genética , Polyomaviridae/isolamento & purificação , Polyomavirus/genética , Polyomavirus/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/veterinária
11.
Acta Ortop Bras ; 26(4): 248-251, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30210254

RESUMO

OBJECTIVE: Patients with metastatic bone lesions have a limited life expectancy. These metastatic lesions compromise the proximal femur, and fractures are quite common. The survival of these patients depends on the behavior of the primary tumor. The aim of this study was to evaluate the quality of life of patients with extensive metastatic lesion of the proximal femur with pathological or imminent fracture, treated with non-conventional endoprosthesis. METHODS: From May 2008 to August 2012, twenty-five (25) patients with bone metastases of the proximal femur, with pathological or imminent fracture were recruited into this study. These patients had survived for at least six weeks after surgery and the TESS questionnaire (Toronto Extremity Salvage Score) was administered. RESULTS: The final score of the TESS was an average of 57 points (SD 23.78 points). There was no significant difference in TESS values considering: sex, presence of fracture, or site of the bone lesion. CONCLUSION: The TESS questionnaire provides information about the function and quality of life of patients with malignant tumors of the lower limbs, from the patient's perspective. The results can be considered positive, when compared to the limited life expectancy and complexity of this group of patients. Level of evidence III, Therapeutic studies, retrospective comparative study.


OBJETIVO: Pacientes com lesões ósseas metastáticas têm expectativa de vida limitada. Essas lesões metastáticas comprometem a parte proximal do fêmur, e as fraturas são bastante comuns. A sobrevida desses pacientes depende do comportamento do tumor primário. O objetivo deste estudo é avaliar a qualidade de vida de pacientes com lesões metastáticas extensas na parte proximal do fêmur com fratura patológica ou iminente, tratados com endopróteses não convencionais. MÉTODOS: De maio de 2008 a agosto de 2012, vinte e cinco (25) pacientes com metástases ósseas da parte proximal do fêmur com fratura patológica ou iminente foram recrutados para este estudo. Esses pacientes tinham sobrevida de pelo menos seis semanas após a cirurgia e o questionário TESS (Toronto Extremity Salvage Score) foi aplicado. RESULTADOS: O escore final do TESS teve média de 57 pontos (DP de 23,78 pontos). Não houve diferença significativa entre os valores do TESS ao se considerar sexo, presença de fratura ou localização da lesão óssea. CONCLUSÃO: O questionário TESS fornece informações sobre a função e a qualidade de vida dos pacientes com tumores malignos dos membros inferiores, do ponto de vista do paciente. Os resultados obtidos podem ser considerados positivos, diante da expectativa de vida limitada e a complexidade desse grupo de pacientes. Nível de evidência III, Estudos terapêuticos, Estudo retrospectivo comparativo .

12.
Acta ortop. bras ; 26(4): 248-251, July-Aug. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-973552

RESUMO

ABSTRACT Objective: Patients with metastatic bone lesions have a limited life expectancy. These metastatic lesions compromise the proximal femur, and fractures are quite common. The survival of these patients depends on the behavior of the primary tumor. The aim of this study was to evaluate the quality of life of patients with extensive metastatic lesion of the proximal femur with pathological or imminent fracture, treated with non-conventional endoprosthesis. Methods: From May 2008 to August 2012, twenty-five (25) patients with bone metastases of the proximal femur, with pathological or imminent fracture were recruited into this study. These patients had survived for at least six weeks after surgery and the TESS questionnaire (Toronto Extremity Salvage Score) was administered. Results: The final score of the TESS was an average of 57 points (SD 23.78 points). There was no significant difference in TESS values considering: sex, presence of fracture, or site of the bone lesion. Conclusion: The TESS questionnaire provides information about the function and quality of life of patients with malignant tumors of the lower limbs, from the patient's perspective. The results can be considered positive, when compared to the limited life expectancy and complexity of this group of patients. Level of evidence III, Therapeutic studies, retrospective comparative study.


RESUMO Objetivo: Pacientes com lesões ósseas metastáticas têm expectativa de vida limitada. Essas lesões metastáticas comprometem a parte proximal do fêmur, e as fraturas são bastante comuns. A sobrevida desses pacientes depende do comportamento do tumor primário. O objetivo deste estudo é avaliar a qualidade de vida de pacientes com lesões metastáticas extensas na parte proximal do fêmur com fratura patológica ou iminente, tratados com endopróteses não convencionais. Métodos: De maio de 2008 a agosto de 2012, vinte e cinco (25) pacientes com metástases ósseas da parte proximal do fêmur com fratura patológica ou iminente foram recrutados para este estudo. Esses pacientes tinham sobrevida de pelo menos seis semanas após a cirurgia e o questionário TESS (Toronto Extremity Salvage Score) foi aplicado. Resultados: O escore final do TESS teve média de 57 pontos (DP de 23,78 pontos). Não houve diferença significativa entre os valores do TESS ao se considerar sexo, presença de fratura ou localização da lesão óssea. Conclusão: O questionário TESS fornece informações sobre a função e a qualidade de vida dos pacientes com tumores malignos dos membros inferiores, do ponto de vista do paciente. Os resultados obtidos podem ser considerados positivos, diante da expectativa de vida limitada e a complexidade desse grupo de pacientes. Nível de evidência III, Estudos terapêuticos, Estudo retrospectivo comparativo.

13.
ACS Chem Biol ; 13(1): 91-99, 2018 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-29205032

RESUMO

A novel linear depsipeptide enriched with tyrosine-derived moieties, termed apratyramide, was isolated from an apratoxin-producing cyanobacterium. The structure was determined using a combination of NMR spectroscopy, mass spectrometry, and chiral analysis of the acid hydrolyzate and confirmed by total synthesis. Apratyramide up-regulated multiple growth factors at the transcript level in human keratinocyte (HaCaT) cells and induced the secretion of vascular endothelial growth factor A (VEGF-A) from HaCaT cells, suggesting the compound's potential wound-healing properties through growth factor induction. Transcriptome analysis and sequential validation supported the hypothesis and indicated its mode of action (MOA) through the unfolded protein response (UPR) pathway, which is functionally related to wound healing and angiogenesis. The conditioned medium of HaCaT cells treated with apratyramide induced angiogenesis in vitro. An ex vivo rabbit corneal epithelial model was applied to confirm the VEGF-A induction in this wound-healing model.


Assuntos
Depsipeptídeos/química , Fator A de Crescimento do Endotélio Vascular/metabolismo , Cicatrização/efeitos dos fármacos , Indutores da Angiogênese/química , Indutores da Angiogênese/farmacologia , Animais , Organismos Aquáticos , Técnicas de Química Sintética , Córnea/efeitos dos fármacos , Córnea/metabolismo , Cianobactérias/química , Depsipeptídeos/farmacologia , Avaliação Pré-Clínica de Medicamentos/métodos , Células HCT116 , Humanos , Queratinócitos/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Coelhos , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/genética , Cicatrização/genética
14.
Environ Entomol ; 47(1): 77-86, 2018 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-29186477

RESUMO

Plants and herbivorous (or parasitic) insects form the majority of macroscopic life. The specificity of interaction between host plant and parasitic insect depends on the adaptations of both the host and the parasite. Over time, these interactions evolve and change as a result of an 'arms race' between host and parasite, and the resulting species-specific adaptations may be maintained, perpetuating these interactions across speciation events. This can lead to specialisation between species or clades. With speciation and species sorting over time, complex interactions evolve. Here, we elucidate a three-tier method to test these interactions using the aphids (Hemiptera: Aphididae) and plants of Churchill (Manitoba, Canada) as a model system. We analyzed these interactions by testing for three patterns in host specificity: monophagy, phylogenetic clustering, and cophylogeny. We defined monophagy strictly as one species feeding exclusively upon a single host plant species (an association likely driven by arms races in morphology, chemical resistance/tolerance, and visual appearance) and observed this in 7 of 22 aphid species. In all the remaining 'polyphagous' cases, there was a strong trend toward monophagy (80% of individuals were found on a single host plant species). Second, we observed two separate examples of phylogenetic clustering where groups of closely related aphid species fed upon individual plant species. Finally, we found no support for cophylogenetic relationships where both aphids and plants cospeciate to form congruent phylogenetic trees (evidence of coadaptation through an ongoing arms race). One explanation for uncovering species-specific interactions in a recently deglaciated, subarctic locality is that the species involved in the associations moved north together. Testing different levels of specificity in the most predominant species-species interactions on the planet will allow us to elucidate these patterns accurately and gives us insight into where to direct future research.


Assuntos
Afídeos/fisiologia , Evolução Biológica , Clima Frio , Herbivoria , Fenômenos Fisiológicos Vegetais , Animais , Cadeia Alimentar , Manitoba , Filogenia , Especificidade da Espécie
15.
J Control Release ; 244(Pt A): 1-13, 2016 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-27810558

RESUMO

A potent anti-vascular endothelial growth factor (VEGF) biologic and a compatible delivery system were co-evaluated for protection against wet age-related macular degeneration (AMD) over a 6month period following a single intravitreal (IVT) injection. The anti-VEGF molecule is dimeric, containing two different anti-VEGF domain antibodies (dAb) attached to a human IgG1 Fc region: a dual dAb. The delivery system is based on microparticles of PolyActive™ hydrogel co-polymer. The molecule was evaluated both in vitro for potency against VEGF and in ocular VEGF-driven efficacy models in vivo. The dual dAb is highly potent, showing a lower IC50 than aflibercept in VEGF receptor binding assays (RBAs) and retaining activity upon release from microparticles over 12months in vitro. Microparticles released functional dual dAb in rabbit and primate eyes over 6months at sufficient levels to protect Cynomolgus against laser-induced grade IV choroidal neovascularisation (CNV). This demonstrates proof of concept for delivery of an anti-VEGF molecule within a sustained-release system, showing protection in a pre-clinical primate model of wet AMD over 6months. Polymer breakdown and movement of microparticles in the eye may limit development of particle-based approaches for sustained release after IVT injection.


Assuntos
Anticorpos/farmacologia , Neovascularização de Coroide/prevenção & controle , Fragmentos Fc das Imunoglobulinas/farmacologia , Fator A de Crescimento do Endotélio Vascular/imunologia , Animais , Anticorpos/imunologia , Neovascularização de Coroide/imunologia , Preparações de Ação Retardada , Portadores de Fármacos , Liberação Controlada de Fármacos , Humanos , Fragmentos Fc das Imunoglobulinas/química , Fragmentos Fc das Imunoglobulinas/imunologia , Imunoglobulina G/química , Imunoglobulina G/imunologia , Imunoglobulina G/farmacologia , Injeções Intravítreas , Lasers , Macaca fascicularis , Microesferas , Tamanho da Partícula , Poliésteres/química , Polietilenoglicóis/química , Coelhos , Degeneração Macular Exsudativa/prevenção & controle
16.
Proc Natl Acad Sci U S A ; 113(41): E6271-E6280, 2016 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-27671644

RESUMO

Axon injury in response to trauma or disease stimulates a self-destruction program that promotes the localized clearance of damaged axon segments. Sterile alpha and Toll/interleukin receptor (TIR) motif-containing protein 1 (SARM1) is an evolutionarily conserved executioner of this degeneration cascade, also known as Wallerian degeneration; however, the mechanism of SARM1-dependent neuronal destruction is still obscure. SARM1 possesses a TIR domain that is necessary for SARM1 activity. In other proteins, dimerized TIR domains serve as scaffolds for innate immune signaling. In contrast, dimerization of the SARM1 TIR domain promotes consumption of the essential metabolite NAD+ and induces neuronal destruction. This activity is unique to the SARM1 TIR domain, yet the structural elements that enable this activity are unknown. In this study, we identify fundamental properties of the SARM1 TIR domain that promote NAD+ loss and axon degeneration. Dimerization of the TIR domain from the Caenorhabditis elegans SARM1 ortholog TIR-1 leads to NAD+ loss and neuronal death, indicating these activities are an evolutionarily conserved feature of SARM1 function. Detailed analysis of sequence homology identifies canonical TIR motifs as well as a SARM1-specific (SS) loop that are required for NAD+ loss and axon degeneration. Furthermore, we identify a residue in the SARM1 BB loop that is dispensable for TIR activity yet required for injury-induced activation of full-length SARM1, suggesting that SARM1 function requires multidomain interactions. Indeed, we identify a physical interaction between the autoinhibitory N terminus and the TIR domain of SARM1, revealing a previously unrecognized direct connection between these domains that we propose mediates autoinhibition and activation upon injury.


Assuntos
Proteínas do Domínio Armadillo/metabolismo , Proteínas do Citoesqueleto/metabolismo , NAD/metabolismo , Domínios e Motivos de Interação entre Proteínas , Trifosfato de Adenosina/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Proteínas do Domínio Armadillo/química , Proteínas do Domínio Armadillo/genética , Axônios/fisiologia , Morte Celular , Linhagem Celular , Proteínas do Citoesqueleto/química , Proteínas do Citoesqueleto/genética , Gânglios Espinais/citologia , Expressão Gênica , Humanos , Camundongos , Camundongos Knockout , Modelos Biológicos , Modelos Moleculares , Mutação , Regeneração Nervosa , Neurônios/fisiologia , Cultura Primária de Células , Multimerização Proteica , Estrutura Secundária de Proteína
17.
J Neurooncol ; 125(3): 457-79, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26530262

RESUMO

QUESTION: What is the optimal imaging technique to be used in the diagnosis of a suspected low grade glioma, specifically: which anatomic imaging sequences are critical for most accurately identifying or diagnosing a low grade glioma (LGG) and do non-anatomic imaging methods and/or sequences add to the diagnostic specificity of suspected low grade gliomas? TARGET POPULATION: These recommendations apply to adults with a newly diagnosed lesion with a suspected or histopathologically proven LGG. LEVEL II: In patients with a suspected brain tumor, the minimum magnetic resonance imaging (MRI) exam should be an anatomic exam with both T2 weighted and pre- and post-gadolinium contrast enhanced T1 weighted imaging. CRITICAL IMAGING FOR THE IDENTIFICATION AND DIAGNOSIS OF LOW GRADE GLIOMA: LEVEL II: In patients with a suspected brain tumor, anatomic imaging sequences should include T1 and T2 weighted and Fluid Attenuation Inversion Recovery (FLAIR) MR sequences and will include T1 weighted imaging after the administration of gadolinium based contrast. Computed tomography (CT) can provide additional information regarding calcification or hemorrhage, which may narrow the differential diagnosis. At a minimum, these anatomic sequences can help identify a lesion as well as its location, and potential for surgical intervention. IMPROVEMENT OF DIAGNOSTIC SPECIFICITY WITH THE ADDITION OF NON-ANATOMIC (PHYSIOLOGIC AND ADVANCED IMAGING) TO ANATOMIC IMAGING: LEVEL II: Class II evidence from multiple studies and a significant number of Class III series support the addition of diffusion and perfusion weighted MR imaging in the assessment of suspected LGGs, for the purposes of discriminating the potential for tumor subtypes and identification of suspicion of higher grade diagnoses. LEVEL III: Multiple series offer Class III evidence to support the potential for magnetic resonance spectroscopy (MRS) and nuclear medicine methods including positron emission tomography and single-photon emission computed tomography imaging to offer additional diagnostic specificity although these are less well defined and their roles in clinical practice are still being defined. QUESTION: Which imaging sequences or parameters best predict the biological behavior or prognosis for patients with LGG? TARGET POPULATION: These recommendations apply to adults with a newly diagnosed lesion with a suspected or histopathologically proven LGG. RECOMMENDATION: Anatomic and advanced imaging methods and prognostic stratification LEVEL III: Multiple series suggest a role for anatomic and advanced sequences to suggest prognostic stratification among low grade gliomas. Perfusion weighted imaging, particularly when obtained as a part of diagnostic evaluation (as recommended above) can play a role in consideration of prognosis. Other imaging sequences remain investigational in terms of their role in consideration of tumor prognosis as there is insufficient evidence to support more formal recommendations as to their use at this time. QUESTION: What is the optimal imaging technique to be used in the follow-up of a suspected (or biopsy proven) LGG? TARGET POPULATION: This recommendation applies to adults with a newly diagnosed low grade glioma. LEVEL II: In patients with a diagnosis of LGG, anatomic imaging sequences should include T2/FLAIR MR sequences and T1 weighted imaging before and after the administration of gadolinium based contrast. Serial imaging should be performed to identify new areas of contrast enhancement or significant change in tumor size, which may signify transformation to a higher grade. LEVEL III: Advanced imaging utility may depend on tumor subtype. Multicenter clinical trials with larger cohorts are needed. For astrocytic tumors, baseline and longitudinal elevations in tumor perfusion as assessed by dynamic susceptibility contrast perfusion MRI are associated with shorter time to tumor progression, but can be difficult to standardize in clinical practice. For oligodendrogliomas and mixed gliomas, MRS may be helpful for identification of progression.


Assuntos
Neoplasias Encefálicas , Glioma , Neuroimagem , Adulto , Humanos , Encéfalo/patologia , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/terapia , Medicina Baseada em Evidências , Glioma/diagnóstico , Glioma/patologia , Glioma/terapia , Gradação de Tumores , Neuroimagem/métodos
18.
Eur J Immunol ; 45(8): 2324-34, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25991034

RESUMO

NK cells play a key role in innate elimination of virally infected or neoplastic cells but they can be circumvented by immunoevasive mechanisms enabling viral spread or tumor progression. Engagement of the NKG2D activating receptor with soluble forms of its ligand is one such mechanism of inducing NK cell hyporesponsiveness. Interestingly, this immunoevasive strategy among others is described at the maternal-fetal interface where tolerance of the semi-allogeneic fetus is required to allow successful human pregnancy. Understanding of maternal-fetal tolerance is increasing but mechanisms preventing alloreactivity of fetal immune cells against the maternal host are less well understood. The study of umbilical cord blood has enabled insight of the fetal immune system, which appears immature and inert. We have found that soluble NKG2D ligands (sNKG2DLs) are present in cord blood plasma (CBP) and associate with adult NK cell hyporesponsiveness demonstrated by reduced CD107a expression and secretion of IFN-γ upon stimulation. The capacity of NK cells to kill K562 cells or proliferate was also reduced by incubation with CBP; however, physical removal of sNKG2DL from CBP restored K562 lytic function and NKG2D expression. Therefore, our results strongly suggest sNKG2DLs are expressed in CBP as a mechanism of fetal-maternal tolerance in human pregnancy.


Assuntos
Sangue Fetal , Imunidade Celular/fisiologia , Peptídeos e Proteínas de Sinalização Intercelular , Células Matadoras Naturais , Troca Materno-Fetal/fisiologia , Adulto , Feminino , Sangue Fetal/imunologia , Sangue Fetal/metabolismo , Regulação da Expressão Gênica/fisiologia , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Peptídeos e Proteínas de Sinalização Intercelular/imunologia , Interferon gama/imunologia , Interferon gama/metabolismo , Células K562 , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Proteína 1 de Membrana Associada ao Lisossomo/biossíntese , Proteína 1 de Membrana Associada ao Lisossomo/imunologia , Masculino , Subfamília K de Receptores Semelhantes a Lectina de Células NK/sangue , Subfamília K de Receptores Semelhantes a Lectina de Células NK/imunologia , Gravidez
19.
Cytotherapy ; 17(1): 58-67, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25457274

RESUMO

BACKGROUND AIMS: With the rising use of umbilical cord blood (UCB) as an alternative source of hematopoietic stem cells, storage inventories of UCB have grown, giving rise to genetically diverse inventories globally. In the absence of reliable markers such as CD34 or counts of colony-forming units, total nucleated cell (TNC) counts are often used as an indicator of potency, and transplant centers worldwide often select units with the largest counts of TNC. As a result, cord blood banks are driven to increase the quality of stored inventories by increasing the TNC count of products stored. However, these banks face challenges in recovering consistent levels of TNC with the use of the standard protocols of automated umbilical cord processing systems, particularly in the presence of input variation both of cord blood volume and TNC count, in which it is currently not possible to process larger but useable UCB units with consequent losses in TNC. METHODS: This report addresses the challenge of recovering consistently high TNC yields in volume reduction by proposing and validating an alternative protocol capable of processing a larger range of units more reliably. RESULTS: This work demonstrates improvements in plastic ware and tubing sets and in the recovery process protocol with consequent productivity gains in TNC yield and a reduction in standard deviation. CONCLUSIONS: This work could pave the way for cord blood banks to improve UCB processing and increase efficiency through higher yields and lower costs.


Assuntos
Transplante de Células-Tronco de Sangue do Cordão Umbilical , Sangue Fetal/citologia , Células-Tronco Hematopoéticas/citologia , Células-Tronco/citologia , Cordão Umbilical/citologia , Armazenamento de Sangue/métodos , Contagem de Células , Transplante de Células-Tronco de Sangue do Cordão Umbilical/métodos , Humanos
20.
Exp Eye Res ; 125: 173-82, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24971495

RESUMO

The effects of a triple combination of siRNAs targeting key scarring genes were assessed using an ex vivo organ culture model of excimer ablated rabbit corneas. The central 6 mm diameter region of fresh rabbit globes was ablated to a depth of 155 microns with an excimer laser. Corneas were excised, cultured at the air-liquid interface in defined culture medium supplemented with transforming growth factor beta 1 (TGFB1), and treated with either 1% prednisolone acetate or with 22.5 µM cationic nanoparticles complexed with a triple combination of siRNAs (NP-siRNA) targeting TGFB1, TGFB Receptor (TGFBR2) and connective tissue growth factor (CTGF). Scar formation was measured using image analysis of digital images and levels of smooth muscle actin (SMA) were assessed in ablated region of corneas using qRT-PCR and immunostaining. Ex vivo cultured corneas developed intense haze-like scar in the wounded areas and levels of mRNAs for pro-fibrotic genes were significantly elevated 3-8 fold in wounded tissue compared to unablated corneas. Treatment with NP-siRNA or steroid significantly reduced quantitative haze levels by 55% and 68%, respectively, and reduced SMA mRNA and immunohistostaining. This ex vivo corneal culture system reproduced key molecular patterns of corneal scarring and haze formation generated in rabbits. Treatment with NP-siRNAs targeting key scarring genes or an anti-inflammatory steroid reduced corneal haze and SMA mRNA and protein.


Assuntos
Cicatriz/prevenção & controle , Córnea , Doenças da Córnea/terapia , Terapia a Laser/efeitos adversos , RNA Interferente Pequeno/uso terapêutico , Actinas/metabolismo , Análise de Variância , Animais , Anti-Inflamatórios/uso terapêutico , Cicatriz/metabolismo , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Córnea/patologia , Córnea/cirurgia , Doenças da Córnea/etiologia , Doenças da Córnea/metabolismo , Modelos Animais de Doenças , Imuno-Histoquímica , Nanopartículas/uso terapêutico , Técnicas de Cultura de Órgãos , Prednisolona/análogos & derivados , Prednisolona/uso terapêutico , RNA Interferente Pequeno/administração & dosagem , Coelhos , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Fator de Crescimento Transformador beta1/metabolismo
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