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1.
J Transl Med ; 22(1): 526, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38822352

RESUMO

BACKGROUND: Neutrophils are granulocytes with essential antimicrobial effector functions and short lifespans. During infection or sterile inflammation, emergency granulopoiesis leads to release of immature neutrophils from the bone marrow, serving to boost circulating neutrophil counts. Steady state and emergency granulopoiesis are incompletely understood, partly due to a lack of genetically amenable models of neutrophil development. METHODS: We optimised a method for ex vivo production of human neutrophils from CD34+ haematopoietic progenitors. Using flow cytometry, we phenotypically compared cultured neutrophils with native neutrophils from donors experiencing emergency granulopoiesis, and steady state neutrophils from non-challenged donors. We carry out functional and proteomic characterisation of cultured neutrophils and establish genome editing of progenitors. RESULTS: We obtain high yields of ex vivo cultured neutrophils, which phenotypically resemble immature neutrophils released into the circulation during emergency granulopoiesis. Cultured neutrophils have similar rates of ROS production and bacterial killing but altered degranulation, cytokine release and antifungal activity compared to mature neutrophils isolated from peripheral blood. These differences are likely due to incomplete synthesis of granule proteins, as demonstrated by proteomic analysis. CONCLUSION: Ex vivo cultured neutrophils are genetically tractable via genome editing of precursors and provide a powerful model system for investigating the properties and behaviour of immature neutrophils.


Assuntos
Antígenos CD34 , Neutrófilos , Humanos , Neutrófilos/metabolismo , Neutrófilos/citologia , Antígenos CD34/metabolismo , Células Cultivadas , Espécies Reativas de Oxigênio/metabolismo , Proteômica , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/citologia , Edição de Genes , Degranulação Celular , Células-Tronco/metabolismo , Células-Tronco/citologia , Citocinas/metabolismo , Fenótipo
2.
Arch Orthop Trauma Surg ; 144(2): 909-916, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37792058

RESUMO

INTRODUCTION: Hip resurfacing (HR) was introduced as a potential alternative to total hip arthroplasty (THA), indicated predominantly for younger, high demand patients. The modern metal-on-metal implant was popularized in the 1990s and early 2000s and promised greater wear resistance. However, its popularity waned due to increased rates of complications related to metal toxicity including pseudo-tumors as well as the recall of many resurfacing implants. The purpose of this study was to conduct a bibliometric analysis and investigate the current trends in hip resurfacing literature. METHODS: Using the keywords "hip resurfacing," publications between 2012 and 2022 were identified on Web of Science Core Collection of Clarivate Analytics. Results were screened for relevance by three independent reviewers using title, abstract, and full text. The retrieved data were evaluated by the bibliometric method. Included articles were imported into CiteSpace 5.7.R1, 64-bit (Drexel University, Philadelphia, PA, USA), VOSviewer 1.6.15 (Leiden University, Leiden, the Netherlands), and the Online Analysis Platform of Literature Metrology to identify trends in publication. RESULTS: Search terms yielded 1200 results and 724 were included in final analysis. A steady decrease of publications was noted over the past decade with less than 40 articles published in 2020 and 2021. The Journal of Hip Arthroplasty (92), Hip International (74), and Clinical Orthopaedics and Related Research (54) published the most articles. Authors from the United States and the United Kingdom published the most studies. High-frequency keywords in co-occurrence and co-cited cluster analysis were metal-on-metal, metal ions, wear, pseudo-tumor, and revision, demonstrating that long-term concerns have been the focus of most recent studies. CONCLUSION: In conclusion, our bibliometric analysis allowed novel exploration and identification of the current research trends, contributions, and the distribution of publications exploring HR. The understanding of HR and the poor long-term outcomes of some resurfacing implants has improved significantly over the past decade, with the most recent focus on failure rates and long-term complications from metal debris. However, the breadth of literature has steadily declined in the past decade, and ultimately demonstrates the decline of scientific interest and focus on novel areas in hip resurfacing and a potential reached consensus.


Assuntos
Artroplastia de Quadril , Prótese de Quadril , Humanos , Artroplastia de Quadril/efeitos adversos , Artroplastia de Quadril/métodos , Prótese de Quadril/efeitos adversos , Desenho de Prótese , Países Baixos , Metais , Bibliometria
3.
J Chem Phys ; 154(24): 244703, 2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34241364

RESUMO

Cancer remains hard to treat, partially due to the non-specificity of chemotherapeutics. Metal-organic frameworks (MOFs) are promising carriers for targeted chemotherapy, yet, to date, there have been few detailed studies to systematically enhance drug loading while maintaining controlled release. In this work, we investigate which molecular simulation methods best capture the experimental uptake and release of cisplatin from UiO-66 and UiO-66(NH2). We then screen a series of biocompatible, pH-sensitive zeolitic imidazolate frameworks (ZIFs) for their ability to retain cisplatin in healthy parts of the patient and release it in the vicinity of a tumor. Pure-component GCMC simulations show that the maximum cisplatin loading depends on the pore volume. To achieve this maximum loading in the presence of water, either the pore size needs to be large enough to occupy both cisplatin and its solvation shell or the MOF-cisplatin interaction must be more favorable than the cisplatin-shell interaction. Both solvated and non-solvated simulations show that cisplatin release rates can be controlled by either decreasing the pore limiting diameters or by manipulating framework-cisplatin interaction energies to create strong, dispersed adsorption sites. The latter method is preferable if cisplatin loading is performed from solution into a pre-synthesized framework as weak interaction energies and small pore window diameters will hinder cisplatin uptake. Here, ZIF-82 is most promising. If it is possible to load cisplatin during crystallization, ZIF-11 would outcompete the other MOFs screened as cisplatin cannot pass through its pore windows; therefore, release rates would be purely driven by the pH triggered framework degradation.


Assuntos
Cisplatino/química , Imidazóis/química , Estruturas Metalorgânicas/química , Zeolitas/química , Modelos Moleculares
4.
Front Hum Neurosci ; 14: 105, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32499685

RESUMO

Magnetoencephalographic imaging (MEGI) offers a non-invasive alternative for defining preoperative language lateralization in neurosurgery patients. MEGI indeed can be used for accurate estimation of language lateralization with a complex language task - auditory verb generation. However, since language function may vary considerably in patients with focal lesions, it is important to optimize MEGI for estimation of language function with other simpler language tasks. The goal of this study was to optimize MEGI laterality analyses for two such simpler language tasks that can have compliance from those with impaired language function: a non-word repetition (NWR) task and a picture naming (PN) task. Language lateralization results for these two tasks were compared to the verb-generation (VG) task. MEGI reconstruction parameters (regions and time windows) for NWR and PN were first defined in a presurgical training cohort by benchmarking these against laterality indices for VG. Optimized time windows and regions of interest (ROIs) for NWR and PN were determined by examining oscillations in the beta band (12-30 Hz) a marker of neural activity known to be concordant with the VG laterality index (LI). For NWR, additional ROIs include areas MTG/ITG and for both NWR and PN, the postcentral gyrus was included in analyses. Optimal time windows for NWR were defined as 650-850 ms (stimulus-locked) and -350 to -150 ms (response-locked) and for PN -450 to -250 ms (response-locked). To verify the optimal parameters defined in our training cohort for NWR and PN, we examined an independent validation cohort (n = 30 for NWR, n = 28 for PN) and found high concordance between VG laterality and PN laterality (82%) and between VG laterality and NWR laterality (87%). Finally, in a test cohort (n = 8) that underwent both the intracarotid amobarbital procedure (IAP) test and MEG for VG, NWR, and PN, we identified excellent concordance (100%) with IAP for VG + NWR + PN composite LI, high concordance for PN alone (87.5%), and moderate concordance for NWR alone (66.7%). These findings provide task options for non-invasive language mapping with MEGI that can be calibrated for language abilities of individual patients. Results also demonstrate that more accurate estimates can be obtained by combining laterality estimates obtained from multiple tasks. MEGI.

5.
Int J Cancer ; 139(4): 841-53, 2016 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-27037842

RESUMO

The engraftment of circulating cancer cells at distal sites represents a key step in the metastatic cascade, yet remains an unexplored target for therapeutic intervention. In this study, we establish that a vaccination strategy yielding an antigen-specific TH 9 response induces long term host surveillance and prevents the engraftment of circulating cancer cells. Specifically, we show that vaccination with a recombinant CEA IgV-like N domain, formulated with the TLR3 ligand poly I:C, elicits a CEA-specific TH 9 response, wherein IL-9 secreting TH cells act in concert with CEA N domain-specific antibodies as well as activated mast cells in preventing tumor cell engraftment. The development of this immune response was dependent on TLR3, since interference with the TLR3-dsRNA complex formation led to a reduction in vaccine-imparted protection and a shift in the resulting immune response toward a TH 2 response. These findings point to the existence of an alternate tumor targeting immune mechanism that can be exploited for the purpose of developing vaccine therapies targeting tumor dissemination and engraftment.


Assuntos
Antígenos de Neoplasias/imunologia , Mastócitos/imunologia , Neoplasias/imunologia , Neoplasias/patologia , Especificidade do Receptor de Antígeno de Linfócitos T/imunologia , Subpopulações de Linfócitos T/imunologia , Animais , Citotoxicidade Celular Dependente de Anticorpos/imunologia , Antígenos de Neoplasias/genética , Vacinas Anticâncer/imunologia , Citocinas/sangue , Citocinas/metabolismo , Modelos Animais de Doenças , Xenoenxertos , Humanos , Interleucina-9/biossíntese , Mastócitos/metabolismo , Camundongos , Camundongos Transgênicos , Metástase Neoplásica , Neoplasias/metabolismo , Transdução de Sinais , Subpopulações de Linfócitos T/metabolismo , Receptor 3 Toll-Like/metabolismo
6.
J Environ Qual ; 44(4): 1321-5, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26437114

RESUMO

The availability of in situ spectrophotometers, such as the S::CAN spectro::lyser, has expanded the possibilities for high-frequency water quality data collection. However, biological and chemical fouling can degrade the performance of in situ spectrophotometers, especially in saline environments with rapid flow rates. A complex freshwater washing system has been previously designed to reduce chemical fouling for the S::CAN spectro::lyser spectrophotometer. In the current study, we present a simpler, cheaper alternative: the attachment of a sacrificial zinc anode. Results are presented detailing the S::CAN spectro::lyser performance with and without the addition of the sacrificial anode. Attachment of the zinc anode provided efficient corrosion protection during 2-wk deployments in a highly dynamic (average tidal range, 2.5 m) saline tidal saltmarsh creek at Groves Creek, Skidaway Institute of Oceanography, Savannah, GA.

7.
Taiwan J Obstet Gynecol ; 53(4): 592-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25510707

RESUMO

OBJECTIVE: Trisomy 9 is a rare chromosomal abnormality usually associated with first-trimester miscarriage; few fetuses survive until the second trimester. We report two new cases of complete trisomy 9 that both present unusual phenotypic associations, and we analyze the genetic pathway involved in this chromosomal abnormality. CASE REPORT: The first fetus investigated showed Dandy-Walker malformation, cleft lip, and cleft palate) at the second trimester scan. Cardiovascular abnormalities were characterized by a right-sided, U-shaped aortic arch associated with a ventricular septal defect (VSD). Symmetrical intrauterine growth restriction and multicystic dysplastic kidney disease were associated findings. The second fetus showed a dysmorphic face, bilateral cleft lip, hypoplastic corpus callosum, and a Dandy-Walker malformation. Postmortem examination revealed cardiovascular abnormalities such as persistent left superior vena cava draining into the coronary sinus, membranous ventricular septal defect, overriding aorta, pulmonary valve with two cusps and three sinuses, and the origin of the left subclavian artery distal to the junction of ductus arteriosus and aortic arch. CONCLUSION: Complete trisomy 9 may result in a wide spectrum of congenital abnormalities, and the presented case series contributes further details on the phenotype of this rare aneuploidy.


Assuntos
Anormalidades Múltiplas/genética , Anormalidades Cardiovasculares/genética , Fenda Labial/genética , Fissura Palatina/genética , Síndrome de Dandy-Walker/genética , Fenótipo , Trissomia , Anormalidades Múltiplas/diagnóstico , Aborto Eugênico , Adulto , Anormalidades Cardiovasculares/diagnóstico , Cromossomos Humanos Par 9 , Fenda Labial/diagnóstico , Fissura Palatina/diagnóstico , Síndrome de Dandy-Walker/diagnóstico , Feminino , Humanos , Gravidez , Segundo Trimestre da Gravidez , Diagnóstico Pré-Natal
8.
Am J Med Genet A ; 161A(7): 1792-6, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23713026

RESUMO

Nephronophthisis associated ciliopathies (NPHP-AC) are a group of phenotypically related conditions that include Joubert syndrome, Meckel syndrome, nephronophthisis (NPHP), and Senior-Loken syndrome. We report on a male fetus with prenatal ultrasound findings at 24 weeks of gestation of anhydramnios, large and echogenic kidneys and situs inversus totalis. Histopathology revealed nephronophthisis and tracheal mucosa electron microscopy revealed ciliary dysgenesis. DNA analysis of the NPHP genes showed a previously unreported homozygous mutation, p.Arg603* (c.1078+1G>A), in the INVS/NPHP2 gene. This mutation is thought to abolish the splice donor site for exon 8, which likely disrupts the normal splicing of the INVS/NPHP2 gene.


Assuntos
Cílios/patologia , Doenças Renais Císticas/genética , Rim/anormalidades , Mutação , Fatores de Transcrição/genética , Feminino , Homozigoto , Humanos , Rim/embriologia , Doenças Renais Císticas/diagnóstico por imagem , Masculino , Gravidez , Sítios de Splice de RNA , Mucosa Respiratória/patologia , Situs Inversus/genética , Situs Inversus/patologia , Ultrassonografia Pré-Natal
9.
J Immunol ; 189(12): 5549-60, 2012 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-23175697

RESUMO

Altered peptide ligands (APLs) with enhanced binding to MHC class I can increase the CD8(+) T cell response to native Ags, including tumor Ags. In this study, we investigate the influence of peptide-MHC (pMHC) stability on recruitment of tumor Ag-specific CD8(+) T cells through cross-priming. Among the four known H-2(b)-restricted CD8(+) T cell determinants within SV40 large tumor Ag (TAg), the site V determinant ((489)QGINNLDNL(497)) forms relatively low-stability pMHC and is characteristically immunorecessive. Absence of detectable site V-specific CD8(+) T cells following immunization with wild-type TAg is due in part to inefficient cross-priming. We mutated nonanchor residues within the TAg site V determinant that increased pMHC stability but preserved recognition by both TCR-transgenic and polyclonal endogenous T cells. Using a novel approach to quantify the fraction of naive T cells triggered through cross-priming in vivo, we show that immunization with TAg variants expressing higher-stability determinants increased the fraction of site V-specific T cells cross-primed and effectively overcame the immunorecessive phenotype. In addition, using MHC class I tetramer-based enrichment, we demonstrate for the first time, to our knowledge, that endogenous site V-specific T cells are primed following wild-type TAg immunization despite their low initial frequency, but that the magnitude of T cell accumulation is enhanced following immunization with a site V variant TAg. Our results demonstrate that site V APLs cross-prime a higher fraction of available T cells, providing a potential mechanism for high-stability APLs to enhance immunogenicity and accumulation of T cells specific for the native determinant.


Assuntos
Antígenos de Neoplasias/genética , Antígenos Transformantes de Poliomavirus/genética , Linfócitos T CD8-Positivos/imunologia , Apresentação Cruzada/imunologia , Epitopos de Linfócito T/genética , Complexo Principal de Histocompatibilidade/genética , Peptídeos/metabolismo , Vírus 40 dos Símios/imunologia , Animais , Antígenos de Neoplasias/metabolismo , Antígenos Transformantes de Poliomavirus/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/patologia , Apresentação Cruzada/genética , Epitopos de Linfócito T/metabolismo , Ativação Linfocitária/genética , Ativação Linfocitária/imunologia , Contagem de Linfócitos , Complexo Principal de Histocompatibilidade/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Estabilidade Proteica , Vírus 40 dos Símios/genética , Células Tumorais Cultivadas , Regulação para Cima/genética , Regulação para Cima/imunologia
10.
J Perioper Pract ; 22(7): 237-41, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22919774

RESUMO

BACKGROUND: Enhanced recovery after surgery (ERAS) or 'fast track' surgery is heavily based on a multidisciplinary focused perioperative care model with all players being equally important for successful implementation. Several institutions run an ERAS course but few data are available on their effect on attitudes and perceptions to perioperative care principles. METHODS: A ten item survey was designed for perioperative care clinicians attending an annual ERAS workshop. The survey was administered one week before and three weeks after the workshop. RESULTS: Seventy seven eligible participants were identified. Forty four (57%) responded to the questionnaire prior to the course. On repeat administration of the survey three weeks after the course there were 28 (36%) responses. The results of the survey indicate that the majority of perioperative care staff were already aware of the evidence behind some of the principles applied in colectomy, with a high pre-course level of understanding shown. However the course significantly changed opinion regarding some other aspects of care to align opinion with evidence amongst the responders. CONCLUSION: There appears to be a high rate of evidence agreement with some interventions but not others amongst perioperative staff. Attending a multidisciplinary ERAS workshop seems to align opinion with evidence.


Assuntos
Educação Continuada , Conhecimentos, Atitudes e Prática em Saúde , Equipe de Assistência ao Paciente , Assistência Perioperatória/métodos , Procedimentos Cirúrgicos Operatórios/reabilitação , Estudos Transversais , Currículo , Prática Clínica Baseada em Evidências/educação , Humanos , Nova Zelândia , Avaliação de Programas e Projetos de Saúde
11.
J Ultrasound Med ; 29(8): 1161-5, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20660449

RESUMO

OBJECTIVE: The appearance of the vertebral artery (VA) waveform on a pulsed Doppler examination performed during standard carotid duplex ultrasonography (CDU) may suggest vertebrobasilar disease. We sought to determine the radiographic importance of high-resistive (HR) pulsed Doppler VA waveforms seen on CDU. METHODS: The Noninvasive Vascular Laboratory database was queried for CDU studies noting the HR VA Doppler signal. Studies with unilateral or bilateral HR and antegrade VA waveforms with correlative neuroimaging studies within 60 days were included. Imaging reports were reviewed to determine the following: (1) a normal VA; (2) at least moderate distal VA or basilar artery (BA) stenosis, occlusion, or dissection; (3) a congenitally diminutive VA; or (4) other abnormalities. RESULTS: Of 1338 studies with 1 or more HR VA waveforms, 79 studies met all inclusion criteria (n = 157 arteries) and had adequate correlative neuroimaging. There were 90 HR VAs, and HR waveforms were equally distributed between right and left sides. The mean peak systolic velocity of HR versus low-resistive (LR) VAs was 51.7 versus 63.6 cm/s (P = .04); the mean end-diastolic velocity of HR versus LR VAs was 4.6 versus 17.3 cm/s (P < .001); and the resistive index of HR versus LR VAs was 0.92 versus 0.73 (P < .001). Of all HR VAs, 18.9% were normal; 38.9% had distal vertebrobasilar stenosis or occlusion; 35.6% were congenitally diminutive; and 6.7% had other abnormalities (proximal stenosis, excessive tortuosity, fibromuscular dysplasia, and BA hypoplasia). CONCLUSIONS: The finding of an HR spectral Doppler signal in the VA was associated with major vertebrobasilar disease (46% of cases) and should prompt additional neuroimaging in the appropriate clinical situation.


Assuntos
Ultrassonografia Doppler Dupla/métodos , Artéria Vertebral/diagnóstico por imagem , Artéria Vertebral/fisiopatologia , Insuficiência Vertebrobasilar/diagnóstico por imagem , Insuficiência Vertebrobasilar/fisiopatologia , Artérias Carótidas/diagnóstico por imagem , Artérias Carótidas/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resistência Vascular
12.
Pediatr Radiol ; 38(12): 1345-9, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18716767

RESUMO

The diastrophic dysplasia family of osteochondrodysplasias comprises a spectrum of skeletal diseases characterized by abnormal growth and remodelling of cartilage and bone. They are caused by mutations in the diastrophic dysplasia sulfate transporter (DTDST) gene. Different defects in this gene product give rise to the variety of phenotypes based on the level of residual transport capacity. We reported a case of a fetus with this spectrum, evaluated and diagnosed with fetal MRI.


Assuntos
Anormalidades Múltiplas/patologia , Doenças Fetais/patologia , Imageamento por Ressonância Magnética/métodos , Osteocondrodisplasias/patologia , Diagnóstico Pré-Natal/métodos , Adulto , Feminino , Humanos , Gravidez , Natimorto
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