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1.
Eur J Surg Oncol ; 48(8): 1718-1722, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35718678

RESUMO

INTRODUCTION: Lymphedema is a condition which heavily impacts patients QoL. For patients who desire autologous breast reconstruction, lymph nodes can be included in the Deep Inferior Epigastric Artery (DIEP) flap combining vascularized lymph node transfer and autologous breast reconstruction. MATERIAL AND METHODS: Patients who received autologous breast reconstruction with a DIEP flap in combination with vascularized lymph nodes were included in this study. Volume measurements pre and post-surgery were analyzed and surveys including two versions of the ULL-27 questionnaire to measure QoL before and after surgery were send. RESULTS: In total, 45 out of 64 patients returned the questionnaires. The average follow up was 51 months. The total ULL-27 score increased with 12.6 points on average (p = 0.00). The subdomain scores (physical, psychological and social) also significantly increased (p = 0.00). In addition 69% of patients were able to decrease physiotherapy, 63% of patients were able to decrease compression garment usage and the incidence of skin infections decreased in 6 patients out of 7 patients who had recurrent skin infections prior to surgery. The volume difference between the affected and the healthy arm did not significantly change (407 ml-406 ml, p = 0.988). CONCLUSIONS: Vascularized lymph node transfer in combination with DIEP flap breast reconstruction can cause a significant improvement on lymphedema related QoL, even when a volume difference decrease is absent. It can also decrease compression garment usage and reduce the need for physiotherapy. Future prospective studies should evaluate these findings and identify patients that benefit most from such procedures.


Assuntos
Linfedema Relacionado a Câncer de Mama , Neoplasias da Mama , Linfedema , Mamoplastia , Retalho Perfurante , Linfedema Relacionado a Câncer de Mama/etiologia , Linfedema Relacionado a Câncer de Mama/cirurgia , Neoplasias da Mama/complicações , Feminino , Humanos , Linfonodos/cirurgia , Linfedema/etiologia , Linfedema/cirurgia , Mamoplastia/métodos , Estudos Prospectivos , Qualidade de Vida
2.
Best Pract Res Clin Rheumatol ; 36(2): 101761, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35760741

RESUMO

Inclusion body myositis (IBM) is a slowly progressive muscle disease affecting ageing individuals. IBM presents with a distinctive pattern of weakness involving the quadriceps and finger flexor muscles, although other muscles including pharyngeal muscles become affected over time. Pathological hallmarks of IBM include autoimmune features, including endomysial infiltration by highly differentiated T cells, as well as degenerative features marked by intramyofibre protein aggregates organised into inclusion bodies. Despite some progress in understanding the cellular pathways involved in IBM, it remains untreatable, and the progression of the disease leads to progressive weakness, disability, wheelchair dependency and loss of independence. Therefore, there is an urgent need to improve our understanding of the underlying mechanisms and pathways involved in this disease to identify new treatment targets. Here, we discuss the current understanding of aetiopathogenesis, the interrelationship between autoimmunity and degeneration, and how ageing is a major influencer of both these features.


Assuntos
Miosite de Corpos de Inclusão , Miosite , Envelhecimento , Autoimunidade , Humanos , Músculos/patologia , Miosite/complicações , Agregados Proteicos
3.
Pediatr Cardiol ; 43(5): 1141-1155, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35157095

RESUMO

Pre-operative feeding may improve long-term feeding outcomes in single ventricle patients, including weaning from supplemental tube feedings in infancy. This study examines the association between pre-operative enteral feeding and subsequent long-term feeding outcomes while also assessing the counterbalancing risk of necrotizing enterocolitis (NEC). Secondary analysis of the National Pediatric Cardiology Quality Improvement Collaborative database was performed. The association between pre-operative feeding practice and achieving all oral feeds through the first year of life was examined using a multivariable regression model. Similarly, the association between pre-operative oral feeding and NEC was also assessed. Of 944 patients with 1-year feeding outcomes available, 58% were fed preoperatively (41.3% exclusively oral) and 12.3% were not fed per institutional approach. At hospital discharge after Stage 1 palliation, 57% required a feeding tube, while 39% required a feeding tube at their first birthday. In infants who were orally fed, the odds ratio to achieving tube-free feeding at 1 year was not significantly increased (1.3, confidence interval 0.8-2.0). Of 1740 infants with pre-operative feeding and Stage 1 there was no statistically significant difference in NEC among patients who were preoperatively fed versus those that were not fed per institutional approach (p = 0.2). Pre-operative feeding of infants with single ventricle heart disease was not associated with early achievement of tube-free feeding in the first year of life. However, pre-operative oral feeding was also not associated with increased risk of NEC, suggesting that it can be safely offered among appropriate patients.


Assuntos
Enterocolite Necrosante , Cardiopatias , Síndrome do Coração Esquerdo Hipoplásico , Doenças do Recém-Nascido , Coração Univentricular , Criança , Nutrição Enteral , Humanos , Síndrome do Coração Esquerdo Hipoplásico/cirurgia , Lactente , Recém-Nascido , Resultado do Tratamento , Coração Univentricular/cirurgia
4.
BJS Open ; 5(1)2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33609388

RESUMO

BACKGROUND: The surgical treatment of patients with complex ventral hernias is challenging. The aim of this study was to present an international overview of expert opinions on current practice. METHODS: A survey questionnaire was designed to investigate preoperative risk management, surgical approach and mesh choice in patients undergoing complex hernias repair, and treatment strategies for infected meshes. Geographical location of practice, experience and annual volumes of the surgeons were compared. RESULTS: Of 408 surgeons, 234 (57.4 per cent) were practising in the USA, 116 (28.4 per cent) in Europe, and 58 (14.2 per cent) in other countries. Some 412 of 418 surgeons (98.6 per cent) performed open repair and 322 of 416 (77.4 per cent) performed laparoscopic repair. Most recommended preoperative work-up/lifestyle changes such as smoking cessation (319 of 398, 80.2 per cent) and weight loss (254 of 399, 63.7 per cent), but the consequences of these strategies varied. American surgeons and less experienced surgeons were stricter. Antibiotics were given at least 1 h before surgery by 295 of 414 respondents (71.3 per cent). Synthetic and biological meshes were used equally in contaminated primary hernia repair, whereas for recurrent hernia repair synthetic mesh was used in a clean environment and biological or no mesh in a contaminated environment. American surgeons and surgeons with less experience preferred biological mesh in contaminated environments significantly more often. Percutaneous drainage and antibiotics were the first steps recommended in treating mesh infection. In the presence of sepsis, most surgeons favoured synthetic mesh explantation and further repair with biological mesh. CONCLUSION: There remains a paucity of good-quality evidence in dealing with these hernias, leading to variations in management. Patient optimization and issues related to mesh choice and infections require well designed prospective studies.


Assuntos
Atitude do Pessoal de Saúde , Hérnia Ventral/cirurgia , Herniorrafia/métodos , Padrões de Prática Médica/estatística & dados numéricos , Telas Cirúrgicas , Adulto , Idoso , Feminino , Pesquisas sobre Atenção à Saúde , Herniorrafia/instrumentação , Humanos , Internacionalidade , Masculino , Pessoa de Meia-Idade
5.
Artigo em Inglês | MEDLINE | ID: mdl-31610481

RESUMO

Traditional chromatographic techniques used in downstream processes of biomolecule manufacturing are often time-consuming and expensive. In this study, a cost-effective microporous micro-capillary film (MMCF) composed of ethylenevinyl alcohol (EVOH) was evaluated for its potential application in immunoadsorption with high process efficiency. A peptide ligand Ac-Phe-Tyr-His-Glu (Ac-FYHE) was immobilized on the inner surface of MMCF for selective binding of human immunoglobulin (hIgG). The porous structure and chemical properties of the prepared MMCF were confirmed by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). hIgG (2 mg/ml) adsorption studies demonstrated that the binding process followed a Langmuir isotherm with equilibrium adsorption capacities of 9.31 and 3.47 mg/ml adsorbent under static and dynamic conditions, respectively. Moreover, the membrane showed good flowrate tolerance when studied under flowrates of 0.5 ml/min to 10 ml/min. hIgG purity was 88.2% when obtained from an hIgG (2 mg/ml) and HSA (8 mg/ml) mixture and the purity remained over 80.0% when hIgG concentrations increased in the mixtures. Moreover, purity of 82.3% was achieved when removing hIgG directly from human serum. The MMCF-Ac-FYHE affinity column is expected to selectively remove hIgG from blood for the treatment of autoimmune diseases with high efficiency and cost effectiveness.


Assuntos
Cromatografia de Afinidade/métodos , Imunoglobulina G/isolamento & purificação , Peptídeos/química , Adsorção , Humanos , Cinética , Ligantes , Estrutura Molecular , Porosidade , Albumina Sérica Humana/química , Relação Estrutura-Atividade , Propriedades de Superfície , Compostos de Vinila/química
6.
Hernia ; 23(2): 347-354, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30847719

RESUMO

BACKGROUND: The component separation technique (CST) is considered an excellent technique for complex ventral hernia repair. However, postoperative infectious complications and reherniation rates are significant. Risk factor analysis for postoperative complication and reherniation has focused mostly on patient history and co-morbidity and shows equivocal results. The use of abdominal morphometrics derived from CT scans to assist in risk assessment seems promising. The aim of this study is to determine the predictability of reherniation and surgical site infections (SSI) using pre-operative CT measurements. METHODS: Electronic patient records were searched for patients who underwent CST between 2000 and 2013 and had a pre-operative CT scan available. Visceral fat volume (VFV), subcutaneous fat volume (SFV), loss of domain (LOD), rectus thickness and width (RT, RW), abdominal volume, hernia sac volume, total fat volume (TFV), sagittal distance (SD) and waist circumference (WC) were measured or calculated. Relevant variables were entered in multivariate regression analysis to determine their effect on reherniation and SSI as separate outcomes. RESULTS: Sixty-five patients were included. VFV (p = 0.025, OR = 1.65) was a significant predictor regarding reherniation. Hernia sac volume (p = 0.020, OR = 2.10) and SFV per 1000 cm3 (p = 0.034, OR = 0.26) were significant predictors of SSI. CONCLUSION: Visceral fat volume, subcutaneous fat volume and hernia sac volume derived from CT scan measurements may be used to predict reherniation and SSI in patients undergoing complex ventral hernia repair using CST. These findings may aid in optimizing patient-tailored preoperative risk assessment.


Assuntos
Hérnia Ventral/diagnóstico por imagem , Herniorrafia/efeitos adversos , Infecção da Ferida Cirúrgica/etiologia , Adulto , Idoso , Feminino , Hérnia Ventral/cirurgia , Herniorrafia/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Tomografia Computadorizada por Raios X , Adulto Jovem
8.
Hernia ; 22(6): 921-939, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30178226

RESUMO

PURPOSE: To provide guidelines for all surgical specialists who deal with the open abdomen (OA) or the burst abdomen (BA) in adult patients both on the methods used to close the musculofascial layers of the abdominal wall, and regarding possible materials to be used. METHODS: The guidelines were developed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach including publications up to January 2017. When RCTs were available, outcomes of interest were quantitatively synthesized by means of a conventional meta-analysis. When only observational studies were available, a meta-analysis of proportions was done. The guidelines were written using the AGREE II instrument. RESULTS: For many of the Key Questions that were researched, there were no high quality studies available. While some strong recommendations could be made according to GRADE, the guidelines also contain good practice statements and clinical expertise guidance which are distinct from recommendations that have been formally categorized using GRADE. RECOMMENDATIONS: When considering the OA, dynamic closure techniques should be prioritized over the use of static closure techniques (strong recommendation). However, for techniques including suture closure, mesh reinforcement, component separation techniques and skin grafting, only clinical expertise guidance was provided. Considering the BA, a clinical expertise guidance statement was advised for dynamic closure techniques. Additionally, a clinical expertise guidance statement concerning suture closure and a good practice statement concerning mesh reinforcement during fascial closure were proposed. The role of advanced techniques such as component separation or relaxing incisions is questioned. In addition, the role of the abdominal girdle seems limited to very selected patients.


Assuntos
Parede Abdominal/cirurgia , Técnicas de Fechamento de Ferimentos Abdominais , Europa (Continente) , Fasciotomia , Humanos , Tratamento de Ferimentos com Pressão Negativa , Complicações Pós-Operatórias/prevenção & controle , Transplante de Pele , Sociedades Médicas , Telas Cirúrgicas
9.
Hernia ; 22(6): 921-939, Sept. 2018.
Artigo em Inglês | BIGG - guias GRADE | ID: biblio-1010376

RESUMO

To provide guidelines for all surgical specialists who deal with the open abdomen (OA) or the burst abdomen (BA) in adult patients both on the methods used to close the musculofascial layers of the abdominal wall, and regarding possible materials to be used. The guidelines were developed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach including publications up to January 2017. When RCTs were available, outcomes of interest were quantitatively synthesized by means of a conventional meta-analysis. When only observational studies were available, a meta-analysis of proportions was done. The guidelines were written using the AGREE II instrument. For many of the Key Questions that were researched, there were no high quality studies available. While some strong recommendations could be made according to GRADE, the guidelines also contain good practice statements and clinical expertise guidance which are distinct from recommendations that have been formally categorized using GRADE. When considering the OA, dynamic closure techniques should be prioritized over the use of static closure techniques (strong recommendation). However, for techniques including suture closure, mesh reinforcement, component separation techniques and skin grafting, only clinical expertise guidance was provided. Considering the BA, a clinical expertise guidance statement was advised for dynamic closure techniques. Additionally, a clinical expertise guidance statement concerning suture closure and a good practice statement concerning mesh reinforcement during fascial closure were proposed. The role of advanced techniques such as component separation or relaxing incisions is questioned. In addition, the role of the abdominal girdle seems limited to very selected patients.


Assuntos
Humanos , Parede Abdominal/cirurgia , Técnicas de Fechamento de Ferimentos Abdominais , Complicações Pós-Operatórias/prevenção & controle , Transplante de Pele
11.
Breast Cancer Res Treat ; 165(2): 321-327, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28608029

RESUMO

INTRODUCTION: Lymphedema can be a debilitating condition, causing a great decrease in a person's quality of life (QoL). Treatment with lymphaticovenular anastomosis (LVA), in which an anastomosis is created between the lymphatic and venous system, may attenuate lymphedema symptoms and reduce swelling. In this study, we share the results using LVA to treat breast cancer-related lymphedema (BCRL) at our institution. MATERIALS AND METHODS: Patients were eligible for inclusion if they suffered from unilateral BCRL, if functional lymphatics were available, if compression therapy was used for at least 6 months, and if the follow-up was 12 months at minimum. Lymph vessel functionality was assessed preoperatively using indocyanine green (ICG). During surgery, 1-3 anastomoses were created and shunt patency was confirmed using ICG. Arm volumes were measured before surgery and at 6- and 12-month follow-up. QoL was measured before surgery and at 6-month follow-up. Arm volume differences between the healthy arm and affected arm were compared between the time points. RESULTS: Twenty-nine consecutive female patients with unilateral BCRL were included. The preoperative mean difference in arm volumes was 701 ± 435 ml (36.9%). This was reduced to 496 ± 302 ml (24.7%) at 6-month follow-up (p = 0.00). At 12-month follow-up, the mean difference in arm volume was 467 ± 303 ml (23.5%) (p = 0.02). The overall perceived QoL was increased from 5.8 ± 1.1 to 7.4 ± 0.7 (p = 0.00). The functionality score decreased from 2.2 to 1.8 (p = 0.00), the appearance score decreased from 2.6 to 1.9 (p = 0.00), the symptoms score decreased from 2.8 to 1.8 (p = 0.00), and the mood score decreased from 2.7 to 1.5 (p = 0.00). Fifteen patients (53.6%) were able to discontinue the use of compression garment. CONCLUSION: Treatment with LVAs is effective in reducing arm volume difference in patients suffering from BCRL. Although no complete reduction of the edema was achieved at 12-month follow-up, the procedure significantly increased the patients' QoL.


Assuntos
Anastomose Cirúrgica/métodos , Veia Axilar/cirurgia , Neoplasias da Mama/complicações , Vasos Linfáticos/cirurgia , Linfedema/etiologia , Linfedema/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Braço/patologia , Feminino , Humanos , Linfedema/diagnóstico , Linfografia , Pessoa de Meia-Idade , Qualidade de Vida , Resultado do Tratamento
12.
Psychol Med ; 47(9): 1678-1689, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28173893

RESUMO

BACKGROUND: Subjective reports of insomnia and hypersomnia are common in bipolar disorder (BD). It is unclear to what extent these relate to underlying circadian rhythm disturbance (CRD). In this study we aimed to objectively assess sleep and circadian rhythm in a cohort of patients with BD compared to matched controls. METHOD: Forty-six patients with BD and 42 controls had comprehensive sleep/circadian rhythm assessment with respiratory sleep studies, prolonged accelerometry over 3 weeks, sleep questionnaires and diaries, melatonin levels, alongside mood, psychosocial functioning and quality of life (QoL) questionnaires. RESULTS: Twenty-three (50%) patients with BD had abnormal sleep, of whom 12 (52%) had CRD and 29% had obstructive sleep apnoea. Patients with abnormal sleep had lower 24-h melatonin secretion compared to controls and patients with normal sleep. Abnormal sleep/CRD in BD was associated with impaired functioning and worse QoL. CONCLUSIONS: BD is associated with high rates of abnormal sleep and CRD. The association between these disorders, mood and functioning, and the direction of causality, warrants further investigation.


Assuntos
Transtorno Bipolar , Ritmo Circadiano/fisiologia , Melatonina/metabolismo , Transtornos do Sono-Vigília , Adulto , Transtorno Bipolar/epidemiologia , Transtorno Bipolar/metabolismo , Transtorno Bipolar/fisiopatologia , Comorbidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Apneia Obstrutiva do Sono/epidemiologia , Apneia Obstrutiva do Sono/metabolismo , Apneia Obstrutiva do Sono/fisiopatologia , Transtornos do Sono do Ritmo Circadiano/epidemiologia , Transtornos do Sono do Ritmo Circadiano/metabolismo , Transtornos do Sono do Ritmo Circadiano/fisiopatologia , Transtornos do Sono-Vigília/epidemiologia , Transtornos do Sono-Vigília/metabolismo , Transtornos do Sono-Vigília/fisiopatologia , Adulto Jovem
13.
Mater Sci Eng C Mater Biol Appl ; 69: 1051-7, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27612802

RESUMO

Biopolymers have become important drug delivery systems for therapeutic molecules by enhancing their accessibility and efficacy intracellularly. However, the transport of these drugs across the cell membrane and their release into the cytosol remain a challenge. The trafficking of poly (l-lysine iso-phthalamide) grafted with phenylalanine (PP-50) was investigated using an osteosarcoma cell line (SAOS-2). Colocalisation of this amphipathic biopolymer with endocytosis tracers, such as transferrin and lactosylceramide, suggested that PP-50 is partially internalised by both clathrin and caveolin-mediated endocytosis. Macropinocytosis was also investigated, but a smaller correlation was found between this mechanism and PP-50 transport. A significant decrease in polymer-mediated calcein uptake was found when cells were pre-incubated with endocytosis inhibitors, suggesting also the use of a combination of mechanisms for cell internalisation. In addition, PP-50 colocalisation with endosome and lysosome pathway markers showed that the polymer was able to escape the endolysosomal compartment before maturation. This is a critical characteristic of a biopolymer towards use as drug delivery systems and biomedical applications.


Assuntos
Portadores de Fármacos/química , Polímeros/química , Linhagem Celular Tumoral , Clatrina/química , Clatrina/metabolismo , Endocitose/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Microscopia de Fluorescência , Nistatina/farmacologia , Fenilalanina/química , Polilisina/química , Polímeros/síntese química
14.
J Chromatogr A ; 1468: 64-72, 2016 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-27638141

RESUMO

In this study, the surface of a microporous walled micro-capillary film (MMCF) was modified into a weak anion exchanger by coupling cyanuric chloride and 2-diethylaminoethylamine (DEAE) to the ethylene-vinyl alcohol (EVOH) matrix. Fourier transform infrared spectroscopy (FTIR) measurements of modified and unmodified MMCFs confirmed the addition of a triazine ring and DEAE onto the membrane. Binding of bovine serum albumin (BSA) at pH 7.2 was found to follow a Langmuir isotherm with a maximum equilibrium binding of 12.4mg BSA/mL adsorbent and 8.2mg BSA/mL adsorbent under static and flow conditions, respectively. The ion exchange capacity, determined by Mohr's titration of chlorine atoms displaced from the functionalised surface, was found to be 195±21µmol Cl-/mL of adsorber, comparable to commercial ion exchangers. BSA adsorption onto the ion exchanger was strongly pH-dependant, with an observed reduction in binding above pH 8.2. Frontal experiments of a BSA (5mg/mL) and lysozyme (5mg/mL) mixture demonstrated successful separation of BSA from lysozyme at more than 97% purity as verified by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). Separation between similarly charged anionic molecules was also achieved using BSA (5mg/mL) and herring sperm DNA (0.25mg/mL). BSA was extracted at 100% purity, demonstrating the ability of MMCF-DEAE to remove significant DNA contamination from a protein solution. These experiments highlight the potential for MMCFs to be used for fast protein purification in preparative chromatography application.


Assuntos
Técnicas de Química Analítica/métodos , Proteínas/isolamento & purificação , Adsorção , Ânions/química , Cromatografia de Afinidade , Eletroforese em Gel de Poliacrilamida , Muramidase/metabolismo , Proteínas/análise , Soroalbumina Bovina/análise , Soroalbumina Bovina/isolamento & purificação , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Cryobiology ; 73(2): 175-80, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27497662

RESUMO

Amphipathic pH-responsive polymers have shown to increase the permeability of cell membranes to trehalose hence improving the cryopreservation of mammalian cells. However, the trafficking of both the polymer and trehalose across the cell membrane has not yet been thoroughly analysed. The objective of this study was to investigate the effect on cryopreservation of the trafficking of the disaccharide trehalose along PP-50, an amphipathic polymer, through an osteosarcoma cell line (SAOS-2). Confocal microscopy analysis confirmed the presence of intracellular labelled trehalose only when incubated in the presence of PP-50. Further analysis confirmed that both trehalose and PP-50 localised in the cytoplasm, accumulated mainly in the perinuclear area. Quantitative analysis of the colocalisation between trehalose and PP-50 showed Pearson and Manders coefficients of 0.862 ± 0.008 and 0.766 ± 0.033, respectively, suggesting a high degree of intracellular colocalisation between these molecules. Cryopreserved cells pre-incubated with trehalose and PP-50 showed increased cryosurvival when compared with cells pre-incubated in the absence of the polymer. PP-50 showed to be directly involved in the uptake of trehalose, a critical characteristic towards use in cryopreservation and biomedical applications.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Criopreservação/métodos , Crioprotetores/metabolismo , Trealose/metabolismo , Linhagem Celular , Humanos , Osteossarcoma , Permeabilidade/efeitos dos fármacos , Polímeros/metabolismo
16.
Nature ; 523(7559): 183-188, 2015 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-26131937

RESUMO

Lenalidomide is a highly effective treatment for myelodysplastic syndrome (MDS) with deletion of chromosome 5q (del(5q)). Here, we demonstrate that lenalidomide induces the ubiquitination of casein kinase 1A1 (CK1α) by the E3 ubiquitin ligase CUL4-RBX1-DDB1-CRBN (known as CRL4(CRBN)), resulting in CK1α degradation. CK1α is encoded by a gene within the common deleted region for del(5q) MDS and haploinsufficient expression sensitizes cells to lenalidomide therapy, providing a mechanistic basis for the therapeutic window of lenalidomide in del(5q) MDS. We found that mouse cells are resistant to lenalidomide but that changing a single amino acid in mouse Crbn to the corresponding human residue enables lenalidomide-dependent degradation of CK1α. We further demonstrate that minor side chain modifications in thalidomide and a novel analogue, CC-122, can modulate the spectrum of substrates targeted by CRL4(CRBN). These findings have implications for the clinical activity of lenalidomide and related compounds, and demonstrate the therapeutic potential of novel modulators of E3 ubiquitin ligases.


Assuntos
Caseína Quinase I/metabolismo , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/fisiopatologia , Talidomida/análogos & derivados , Ubiquitinação/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Caseína Quinase I/genética , Linhagem Celular , Regulação da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Humanos , Fatores Imunológicos/farmacologia , Células Jurkat , Células K562 , Lenalidomida , Camundongos , Dados de Sequência Molecular , Peptídeo Hidrolases/química , Proteólise/efeitos dos fármacos , Alinhamento de Sequência , Deleção de Sequência , Especificidade da Espécie , Talidomida/farmacologia , Ubiquitina-Proteína Ligases/metabolismo
17.
J Chromatogr A ; 1394: 148-53, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25840664

RESUMO

Micro-capillary film (MCF) membranes are effective platforms for bioseparations and viable alternatives to established packed bed and membrane substrates at the analytical and preparative chromatography scales. Single hollow fibre (HF) MCF membranes with varied microstructures were produced in order to evaluate the effect of the bore fluid composition used during hollow fibre extrusion on their structure and performance as cation-exchange adsorbers. Hollow fibres were fabricated from ethylene-vinyl alcohol (EVOH) copolymer through solution extrusion followed by nonsolvent induced phase separation (NIPS) using bore fluids of differing composition (100wt.% N-methyl-2-pyrrolidone (NMP), 100wt.% glycerol, 100wt.% water). All HFs displayed highly microporous and mesoporous microstructures, with distinct regions of pore size <1µm, 5-15µm and up to 50µm in diameter, depending upon proximity to the bore fluid. Scanning electron microscopy (SEM) revealed skins of pore size <1µm at the inner surface of HFs produced with water and glycerol, while NMP bore fluid resulted in a skinless inner HF surface. The HFs were modified for chromatography by functionalising the polymer surface hydroxyl groups with sulphonic acid (SP) groups to produce cation-exchange adsorbers. The maximum binding capacities of the HFs were determined by frontal analysis using lysozyme solutions (0.05-100mgml(-1)) for a flow rate of 1.0mlmin(-1). The NMP-HF-SP module displayed the largest maximum lysozyme binding capacity of all the fibres produced (40.3mg lysozyme/ml adsorbent volume), a nearly 2-fold increase over the glycerol and 10-fold increase over the water variants at the same sample flow rate. The importance of NMP as a bore fluid to hollow fibre membrane performance as a result of inner surface porosity was established with a view to applying this parameter for the optimisation of multi-capillary MCF performance in future studies.


Assuntos
Cromatografia por Troca Iônica/instrumentação , Glicerol/química , Membranas Artificiais , Polivinil/química , Pirrolidinonas/química , Água/química , Adsorção , Cromatografia por Troca Iônica/métodos , Muramidase/análise , Porosidade , Ácidos Sulfônicos/química
18.
Br J Haematol ; 167(4): 524-528, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25098371

RESUMO

Haploinsufficiency of ribosomal proteins (RPs) and upregulation of the tumour suppressor TP53 have been shown to be the common basis for the anaemia observed in Diamond Blackfan anaemia and 5q- myelodysplastic syndrome. We previously demonstrated that treatment with L-Leucine resulted in a marked improvement in anaemia in disease models. To determine if the L-Leucine effect was Tp53-dependent, we used antisense MOs to rps19 and rps14 in zebrafish; expression of tp53 and its downstream target cdkn1a remained elevated following L-leucine treatment. We confirmed this observation in human CD34+ cells. L-Leucine thus alleviates anaemia in RP-deficient cells in a TP53-independent manner.


Assuntos
Anemia de Diamond-Blackfan/tratamento farmacológico , Anemia Macrocítica/tratamento farmacológico , Proteína Supressora de Tumor p53/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Anemia de Diamond-Blackfan/genética , Anemia de Diamond-Blackfan/metabolismo , Anemia de Diamond-Blackfan/patologia , Anemia Macrocítica/genética , Anemia Macrocítica/metabolismo , Anemia Macrocítica/patologia , Animais , Deleção Cromossômica , Cromossomos Humanos Par 5/genética , Cromossomos Humanos Par 5/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Modelos Animais de Doenças , Humanos , Leucina , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Proteína Supressora de Tumor p53/genética , Proteínas de Peixe-Zebra/genética
19.
J Chromatogr A ; 1340: 24-32, 2014 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-24685165

RESUMO

The ability of an anion exchange membrane to purify a γ-retrovirus was assessed and optimised with respect to different loading and wash buffers. Recoveries of infectious virus greater than 50% were consistently obtained, while specific titre was increased up to one thousand fold when compared to the material loaded. Specific proteins removed and retained by this optimised process were identified by mass spectrometry. It was possible to successfully bind and elute the equivalent of 1.27 × 10(8) Ifu/ml of ion exchange membrane. This could then be highly concentrated, with infectious virus concentrated to a maximum of 420-fold compared to the load.


Assuntos
Cromatografia por Troca Iônica/métodos , Vetores Genéticos/isolamento & purificação , Retroviridae/isolamento & purificação , Animais , Linhagem Celular , Vetores Genéticos/química , Vírus da Leucemia Murina/química , Vírus da Leucemia Murina/isolamento & purificação , Proteínas Virais/análise
20.
Hernia ; 18(1): 7-17, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24150721

RESUMO

PURPOSE: A clear definition of "complex (abdominal wall) hernia" is missing, though the term is often used. Practically all "complex hernia" literature is retrospective and lacks proper description of the population. There is need for clarification and classification to improve patient care and allow comparison of different surgical approaches. The aim of this study was to reach consensus on criteria used to define a patient with "complex" hernia. METHODS: Three consensus meetings were convened by surgeons with expertise in complex abdominal wall hernias, aimed at laying down criteria that can be used to define "complex hernia" patients, and to divide patients in severity classes. To aid discussion, literature review was performed to identify hernia classification systems, and to find evidence for patient and hernia variables that influence treatment and/or prognosis. RESULTS: Consensus was reached on 22 patient and hernia variables for "complex" hernia criteria inclusion which were grouped under four categories: "Size and location", "Contamination/soft tissue condition", "Patient history/risk factors", and "Clinical scenario". These variables were further divided in three patient severity classes ('Minor', 'Moderate', and 'Major') to provide guidance for peri-operative planning and measures, the risk of a complicated post-operative course, and the extent of financial costs associated with treatment of these hernia patients. CONCLUSION: Common criteria that can be used in defining and describing "complex" (abdominal wall) hernia patients have been identified and divided under four categories and three severity classes. Next step would be to create and validate treatment algorithms to guide the choice of surgical technique including mesh type for the various complex hernias.


Assuntos
Hérnia Abdominal/classificação , Hérnia Abdominal/patologia , Hérnia Abdominal/cirurgia , Humanos , Planejamento de Assistência ao Paciente , Recidiva , Fatores de Risco , Índice de Gravidade de Doença , Telas Cirúrgicas , Terminologia como Assunto
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