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 VidaRESUMO
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-IdadeRESUMO
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 (2â¯mg/ml) adsorption studies demonstrated that the binding process followed a Langmuir isotherm with equilibrium adsorption capacities of 9.31 and 3.47â¯mg/ml adsorbent under static and dynamic conditions, respectively. Moreover, the membrane showed good flowrate tolerance when studied under flowrates of 0.5â¯ml/min to 10â¯ml/min. hIgG purity was 88.2% when obtained from an hIgG (2â¯mg/ml) and HSA (8â¯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/químicaRESUMO
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 JovemRESUMO
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 CirúrgicasRESUMO
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 TratamentoRESUMO
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 químicaRESUMO
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/metabolismoRESUMO
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/metabolismoRESUMO
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/genéticaRESUMO
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/análiseRESUMO
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 AssuntoRESUMO
Lenalidomide is a drug with clinical efficacy in multiple myeloma and other B cell neoplasms, but its mechanism of action is unknown. Using quantitative proteomics, we found that lenalidomide causes selective ubiquitination and degradation of two lymphoid transcription factors, IKZF1 and IKZF3, by the CRBN-CRL4 ubiquitin ligase. IKZF1 and IKZF3 are essential transcription factors in multiple myeloma. A single amino acid substitution of IKZF3 conferred resistance to lenalidomide-induced degradation and rescued lenalidomide-induced inhibition of cell growth. Similarly, we found that lenalidomide-induced interleukin-2 production in T cells is due to depletion of IKZF1 and IKZF3. These findings reveal a previously unknown mechanism of action for a therapeutic agent: alteration of the activity of an E3 ubiquitin ligase, leading to selective degradation of specific targets.
Assuntos
Antineoplásicos/farmacologia , Fator de Transcrição Ikaros/metabolismo , Mieloma Múltiplo/metabolismo , Talidomida/análogos & derivados , Linhagem Celular Tumoral , Células HEK293 , Humanos , Fator de Transcrição Ikaros/genética , Interleucina-2/biossíntese , Lenalidomida , Proteólise , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Talidomida/farmacologia , UbiquitinaçãoRESUMO
Lenalidomide and its analogs, thalidomide and pomalidomide, specifically inhibit growth of mature B-cell lymphomas, including multiple myeloma, and induce interleukin-2 (IL-2) release from T cells. We recently found that this results from activation of the CRBN-CRL4 E3 ubiquitin ligase to degrade the lymphoid transcription factors IKZF1 (Ikaros) and IKZF3 (Aiolos).
RESUMO
A new disposable adsorbent material for fast anion-exchange capture of nano-complexes without prefiltering, clarification or pre-processing of samples was developed based on plastic microcapillary films (MCFs). An MCF containing 19 parallel microcapillaries, each with a mean internal diameter of 142 ± 10 µm, was prepared using a melt extrusion process from an ethylene-vinyl alcohol copolymer (EVOH). The MCF internal surfaces were functionalised using branched chain chemistries to attach quaternary amine groups producing an anion-exchange adsorbent. The purification of nano-complexes using this newly fabricated MCF-EVOH-Q was successfully demonstrated with the capture of lentivirus from pre-filtered culture harvest. This 5m chromatographic substrate was found to bind and elute â¼40% of bound lentivirus or 2.5 × 10(6)infectious units (ifu). The unique properties of this chromatographic substrate that allow the passage of large particulates was further demonstrated with the capture of lentiviral particles from unfiltered un-processed culture media containing cells and cell debris. Using this approach, 56% or 1 × 10(7)ifu of captured lentivirus was eluted. A device based on this new material might be used at an early stage in clinical lentiviral production to harvest lentiviral particles, directly from bioreactors.
Assuntos
Técnicas de Cultura de Células/métodos , Cromatografia por Troca Iônica/instrumentação , Cromatografia por Troca Iônica/métodos , Vetores Genéticos/isolamento & purificação , Lentivirus/isolamento & purificação , Linhagem Celular Tumoral , Eletroforese em Gel de Poliacrilamida , Células HEK293 , Humanos , Polivinil/químicaRESUMO
Over the past decade, genetic lesions that cause ribosome dysfunction have been identified in both congenital and acquired human disorders. These discoveries have established a new category of disorders, known as ribosomopathies, in which the primary pathophysiology is related to impaired ribosome function. The protoptypical disorders are Diamond-Blackfan anemia, a congenital bone marrow failure syndrome, and the 5q- syndrome, a subtype of myelodysplastic syndrome. In both of these disorders, impaired ribosome function causes a severe macrocytic anemia. In this review, we will discuss the evidence that defects in ribosomal biogenesis cause the hematologic phenotype of Diamond-Blackfan anemia and the 5q- syndrome. We will also explore the potential mechanisms by which a ribosomal defect, which would be expected to have widespread consequences, may lead to specific defects in erythropoiesis.
Assuntos
Anemia Aplástica/metabolismo , Doenças Metabólicas/metabolismo , Proteínas Ribossômicas/metabolismo , Ribossomos/metabolismo , Anemia Aplástica/genética , Anemia de Diamond-Blackfan/genética , Anemia de Diamond-Blackfan/metabolismo , Humanos , Doenças Metabólicas/genética , Proteínas Ribossômicas/genéticaRESUMO
Histidine-tagged lentiviral vectors were separated from crude cell culture supernatant using labscale monolithic adsorbents by immobilized metal affinity chromatography. The capture capacity, concentration factor, purification factor, and elution efficiency of a supermacroporous cryogel monolith were evaluated against the BIA Separations convective interaction media (CIM) disc, which is a commercial macroporous monolith. The morphology of the polymeric cryogel material was characterised by scanning electron microscopy. Iminodiacetic acid was used as the metal chelating ligand in both monoliths and the chelating capacity for metal ions was found to be comparable. The CIM-IDA-Ni(2+) adsorbent had the greatest capture capacity (6.7 x 10(8) IU/ml of adsorbent), concentration factor (1.3-fold), and elution efficiency (69%). Advantages of the cryogel monoliths included rapid, low pressure processing as well low levels of protein and DNA in the final purified vector preparations.
Assuntos
Cromatografia de Afinidade/métodos , Vetores Genéticos/isolamento & purificação , Lentivirus/isolamento & purificação , Linhagem Celular Tumoral , Cobalto/química , Cobre/química , Histidina/química , Humanos , Iminoácidos/química , Níquel/químicaRESUMO
Biological adhesives, natural and synthetic, are of current active interest. These adhesives offer significant advantages over traditional sealant techniques, in particular, they are easier to use, and can play an integral part in the healing mechanism of tissue. Thus, biological adhesives can play a major role in medical applications if they possess adequate mechanical behavior and stability over time. In this work, we report on the method of preparation of bovine serum albumin (BSA) into a biological adhesive. We present quantitative measurements that show the effect of BSA concentration and cross-linker content on the bonding strength of BSA adhesive to wood. A comparison is then made with synthetic poly(glycidyl methacrylate) (PGMA) adhesive, and a commercial cyanoacrylate glue, which was used as a control adhesive. In addition, BSA samples were prepared and characterized for their water content, tensile strength, and elasticity. We show that on dry surface, BSA adhesive exhibits a high bonding strength that is comparable with non-biological commercial cyanoacrylate glues, and synthetic PGMA adhesive. Tensile testing on wet wood showed a slight increase in the bonding strength of BSA adhesive, a considerable decrease in the bonding strength of cyanoacrylate glue, and negligible adhesion of PGMA. Tests performed on BSA samples demonstrate that initial BSA concentration and final water content have a significant effect on the stress-strain behavior of the samples.
Assuntos
Adesivos/química , Materiais Biocompatíveis/química , Soroalbumina Bovina/química , Animais , Bioprótese , Bovinos , Reagentes de Ligações Cruzadas/química , Desenho de Equipamento , Ácidos Polimetacrílicos/química , Pressão , Estresse Mecânico , Resistência à Tração , Aderências Teciduais , Água/química , MadeiraRESUMO
The incidence of patients presenting with both ruptured abdominal aortic aneurysm (RAAA) and elective abdominal aortic aneurysm (EAAA) increases with age. The aim of our study was to find out the incidence of RAAA, age and sex groups of patients at risk, and 30-day all-cause perioperative mortality associated with RAAA as well as EAAA repair in a busy district general hospital over a 15-year time period. All patients operated for AAA during 1989-2003, both elective and ruptured, were included in the study. Patients who died in the community from RAAA were also included. The data were collected from the hospital information system, theater logbooks, intensive therapy unit records, postmortem register, and patients' medical notes. We divided the data for RAAA into two groups of 7.5 years each to see if there was any improvement over time in 30-day postoperative mortality. There were 816 cases of AAA, which included 468 RAAAs (57%) and 348 EAAAs (43%). Out of 468 RAAAs, 243 patients had emergency repair, of whom 213 were males. There were 201 patients who had RAAA postmortem (43%). Median age (range) was 73 (54-94) years in males and 77 (52-99) years in females, with a male-to-female ratio of 7:1. The peak incidence of RAAA was over 60 years of age in males and 70 years in females. Incidence of RAAA was 7.3/100,000/year in males and 5/100,000/year in females. For RAAA, 30-day perioperative mortality was 43% (105/243) while overall mortality was 70% (330/468), which includes deaths in the community. There was no improvement in 30-day mortality over time after comparing data for the first 7.5 years (50/115, 43.5%) with those for the second set of 7.5 years (55/128, 43%). There were 348 patients who had EAAA repair over the same period, comprising 282 males, with a male:female ratio of 4.3:1. The 30-day mortality in the elective group was 7.75%. Incidence and mortality of RAAA remain high. A high proportion of patients with AAA remain undiagnosed and die in the community. More lives may be saved if a screening program is started for AAA.
Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Ruptura Aórtica/cirurgia , Hospitais Gerais/estatística & dados numéricos , Procedimentos Cirúrgicos Vasculares/estatística & dados numéricos , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Aneurisma da Aorta Abdominal/diagnóstico , Aneurisma da Aorta Abdominal/mortalidade , Ruptura Aórtica/diagnóstico , Ruptura Aórtica/mortalidade , Procedimentos Cirúrgicos Eletivos/estatística & dados numéricos , Serviços Médicos de Emergência/estatística & dados numéricos , Inglaterra/epidemiologia , Feminino , Humanos , Incidência , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Estudos Retrospectivos , Distribuição por Sexo , Fatores de Tempo , Resultado do TratamentoRESUMO
Action potential firing rates are generally limited by the refractory period, which depends on the recovery from inactivation of voltage-gated Na channels. In cerebellar Purkinje neurons, the kinetics of Na channels appear specialized for rapid firing. Upon depolarization, an endogenous open-channel blocker rapidly terminates current flow but prevents binding of the "fast" inactivation gate. Upon repolarization, unbinding of the blocker produces "resurgent" Na current while allowing channels to recover rapidly. Because other cerebellar neurons, including granule cells, unipolar brush cells, and neurons of the cerebellar nuclei, also fire rapidly, we tested whether these cells might also express Na channels with resurgent kinetics. Neurons were acutely isolated from mice and rats, and TTX-sensitive Na currents were recorded under voltage clamp. Unlike Purkinje cells, the other cerebellar neurons produced only tiny resurgent currents in solutions optimized for voltage-clamping Na currents (50 mM Na+; Co2+ substitution for Ca2+). Under more physiological ionic conditions (155 mM Na+; 2 mM Ca2+ with 0.03 mM Cd2+), however, granule cells, unipolar brush cells, and cerebellar nuclear cells all produced robust resurgent currents. The increase in resurgent current, which was greater than predicted by the Goldman-Hodgkin-Katz equation, appeared to result from a combination of knock-off of open-channel blockers by permeating ions as well as relief of divalent block at negative potentials. These results indicate that resurgent current is typical of many cerebellar neurons and suggest that rapid open-channel block and unblock may be a widespread mechanism for restoration of Na channel availability in rapidly firing neurons.