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1.
World J Surg ; 44(6): 1745-1754, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32052105

RESUMO

PURPOSE: The study investigates whether postoperative complications in elective surgery can be reduced by using a risk calculator via raising the awareness of the surgeon in a preoperative briefing. Postoperative complications like wound infections or pneumonia result in a high burden for healthcare systems. Multiple quality improvement programs address this problem like the ACS NSQIP Surgical Risk Calculator® (SRC). METHODS: To determine whether the preoperative usage of the SRC could reduce inpatient postoperative complications, two groups of 832 patients each were compared using propensity score matching. The SRC was employed retrospectively in the period 2012/2013 in one group ("Retro") and prospectively in the other group ("Prosp") in the period 2014/2015. Actual inpatient postoperative complications were classified by SRC complication categories and compared with the Clavien-Dindo complication classification system (Dindo et al. in Ann Surg 240:205-213, 2004). RESULTS: Comparing SRC "serious complication" and SRC "any complication," a nonsignificant increase in the "Prosp"-group was apparent (serious complication: 6.6% vs. 8.5%, p = 0.164; any complication: 8.5% vs. 9.7%, p = 0.444). CONCLUSION: Use of the SRC neither reduces inpatient postoperative complications nor the severity of complications. The calculations of the SRC rely on a 30-day postoperative follow-up. Poor sensitivity and medium specificity of the SRC showed that the SRC could not make accurate predictions in a short follow-up time averaging 6 days. Alternatively, since the observed complication rate was low in our study, in an environment of already highly implemented risk management tools, reductions in complications are not easily achieved.


Assuntos
Complicações Pós-Operatórias/prevenção & controle , Melhoria de Qualidade , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos de Cirurgia Plástica/efeitos adversos , Estudos Retrospectivos , Medição de Risco
2.
Int J Eat Disord ; 52(3): 309-313, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30746736

RESUMO

OBJECTIVE: We examined whether eating disorder (ED) outcome trajectories during residential treatment differed for patients screening positive for comorbid borderline personality disorder (BPD) and/or substance use disorders (SUDs) than those who do not. METHOD: We examined data from patients in a residential ED treatment program. Patients completed validated self-report surveys to screen for SUDs and BPD on admission, and the ED Examination-Questionnaire (EDE-Q) on admission and every 2 weeks until discharge (N = 479 females). RESULTS: Fifty-four percent screened positive for at least one co-occurring condition. At admission, patients screening positive for SUD and/or BPD had significantly greater eating pathology than patients screening negative for both (t[477] = 8.23, p < .001). Patients screening positive for SUD (independent of BPD screening status) had a significantly faster rate of symptom improvement during the initial 4 weeks than patients screening positive for BPD only and those with no comorbidities. DISCUSSION: Screening positive for SUD and/or BPD was common in residential ED treatment, and associated with more severe ED symptoms. Screening positive for SUD was associated with faster ED symptom improvement than screening positive for BPD. These findings suggest that intensive ED treatment, even in the absence of intensive SUD treatment, may enhance patient outcomes for those with SUDs.


Assuntos
Transtorno da Personalidade Borderline/complicações , Transtornos da Alimentação e da Ingestão de Alimentos/complicações , Transtornos Relacionados ao Uso de Substâncias/complicações , Adolescente , Transtorno da Personalidade Borderline/epidemiologia , Comorbidade , Feminino , Humanos , Masculino , Programas de Rastreamento , Tratamento Domiciliar , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Inquéritos e Questionários , Resultado do Tratamento
3.
Int J Eat Disord ; 50(8): 906-916, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28489323

RESUMO

OBJECTIVE: This study evaluated the DSM-5 severity specifiers for treatment-seeking groups of participants with anorexia nervosa (AN), the purging form of bulimia nervosa (BN), and binge-eating disorder (BED). METHOD: Hundred and sixty-two participants with AN, 93 participants with BN, and 343 participants with BED were diagnosed using semi-structured interviews, sub-categorized using DSM-5 severity specifiers and compared on demographic and cross-sectional clinical measures. RESULTS: In AN, the number of previous hospitalizations and the duration of illness increased with severity, but there was no difference across severity groups on measures of eating pathology, depression, or measures of self-reported physical or emotional functioning. In BN, the level of eating concerns increased across the severity groups, but the groups did not differ on measures of depression, self-esteem, and most eating pathology variables. In BN, support was also found for an alternative severity classification scheme based upon number of methods of purging. In BED, levels of several measures of eating pathology and self-reported physical and emotional functioning increased across the severity groups. For BED, however, support was also found for an alternative severity classification scheme based upon overvaluation of shape and weight. Preliminary evidence was also found for a transdiagnostic severity index based upon overvaluation of shape and weight. DISCUSSION: Overall, these data show limited support for the DSM-5 severity specifiers for BN and modest support for the DSM-5 severity specifiers for AN and BED.


Assuntos
Transtorno da Compulsão Alimentar/diagnóstico , Manual Diagnóstico e Estatístico de Transtornos Mentais , Adulto , Transtorno da Compulsão Alimentar/psicologia , Estudos Transversais , Feminino , Humanos , Adulto Jovem
4.
Int J Eat Disord ; 44(4): 340-8, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21472753

RESUMO

OBJECTIVE: To examine the multidimensional nature of motivation to change in an adolescent sample in residential eating disorder (ED) treatment and relate it to outcome. METHOD: To determine whether different dimensions of motivation (benefits, burdens, and functional avoidance) are differentially associated with symptom severity and outcome, we assessed eating pathology and motivation to change in consecutively admitted female patients (n = 67) with AN, BN, and EDNOS in a residential ED program with the Eating Disorder Examination Questionnaire (EDE-Q) and the Decisional Balance Scale (DB). RESULTS: Pretreatment DB benefits and functional avoidance subscales were correlated with ED and comorbid psychopathology. Admission to discharge change in DB benefits-but not other measured dimensions of motivation was significantly associated with post-treatment EDE-Q global scores. DISCUSSION: Our findings support that motivation to change is a multidimensional construct among ED patients. A reduction in perceived benefits of illness is associated with less severe post-treatment eating pathology.


Assuntos
Transtornos da Alimentação e da Ingestão de Alimentos/psicologia , Transtornos da Alimentação e da Ingestão de Alimentos/terapia , Motivação , Tratamento Domiciliar , Adolescente , Análise de Variância , Imagem Corporal , Feminino , Humanos , Satisfação Pessoal , Psicometria , Qualidade de Vida , Inquéritos e Questionários , Resultado do Tratamento , Adulto Jovem
5.
J Bone Miner Res ; 36(11): 2116-2126, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34355814

RESUMO

Anorexia nervosa is complicated by low bone mineral density (BMD) and increased fracture risk associated with low bone formation and high bone resorption. The lumbar spine is most severely affected. Low bone formation is associated with relative insulin-like growth factor 1 (IGF-1) deficiency. Our objective was to determine whether bone anabolic therapy with recombinant human (rh) IGF-1 used off-label followed by antiresorptive therapy with risedronate would increase BMD more than risedronate or placebo in women with anorexia nervosa. We conducted a 12-month, randomized, placebo-controlled study of 90 ambulatory women with anorexia nervosa and low areal BMD (aBMD). Participants were randomized to three groups: 6 months of rhIGF-1 followed by 6 months of risedronate ("rhIGF-1/Risedronate") (n = 33), 12 months of risedronate ("Risedronate") (n = 33), or double placebo ("Placebo") (n = 16). Outcome measures were lumbar spine (1° endpoint: postero-anterior [PA] spine), hip, and radius aBMD by dual-energy X-ray absorptiometry (DXA), and vertebral, tibial, and radial volumetric BMD (vBMD) and estimated strength by high-resolution peripheral quantitative computed tomography (HR-pCT) (for extremity measurements) and multi-detector computed tomography (for vertebral measurements). At baseline, mean age, body mass index (BMI), aBMD, and vBMD were similar among groups. At 12 months, mean PA lumbar spine aBMD was higher in the rhIGF-1/Risedronate (p = 0.03) group and trended toward being higher in the Risedronate group than Placebo. Mean lateral lumbar spine aBMD was higher, in the rhIGF-1/Risedronate than the Risedronate or Placebo groups (p < 0.05). Vertebral vBMD was higher, and estimated strength trended toward being higher, in the rhIGF-1/Risedronate than Placebo group (p < 0.05). Neither hip or radial aBMD or vBMD, nor radial or tibial estimated strength, differed among groups. rhIGF-1 was well tolerated. Therefore, sequential therapy with rhIGF-1 followed by risedronate increased lateral lumbar spine aBMD more than risedronate or placebo. Strategies that are anabolic and antiresorptive to bone may be effective at increasing BMD in women with anorexia nervosa. © 2021 American Society for Bone and Mineral Research (ASBMR).


Assuntos
Anorexia Nervosa , Densidade Óssea , Fator de Crescimento Insulin-Like I , Ácido Risedrônico/uso terapêutico , Absorciometria de Fóton , Anorexia Nervosa/complicações , Anorexia Nervosa/tratamento farmacológico , Feminino , Humanos , Fator de Crescimento Insulin-Like I/uso terapêutico , Vértebras Lombares/diagnóstico por imagem , Proteínas Recombinantes/uso terapêutico
6.
Opt Express ; 18(5): 4510-7, 2010 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20389463

RESUMO

The generation of hollow beams by a multimode light guiding device is analyzed. The light propagation through the light guide is simulated by ray tracing. It is shown that hollow beams are generated by light rays that propagate along a spiral path through the light guide. The properties of the hollow beam depend on the tilt angle and location of the input beam on the front surface of the light guide. The properties of the output beam are investigated experimentally.

7.
Psychiatry Res ; 178(3): 511-7, 2010 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-20591498

RESUMO

The clinical utility of the DSM-IV eating disorder (ED) diagnostic criteria among practicing clinicians has not been formally evaluated, despite the considerable diagnostic challenges these disorders present. This study evaluated inter-rater reliability between research and clinical diagnoses, identified discrepantly rated diagnostic criteria, and evaluated ED subtype use in a naturalistic treatment setting. Seventy-six adolescent and young adult female patients consecutively admitted to a residential ED program were evaluated independently by clinicians (unstructured clinical interview) and research assessors (Structured Clinical Interview for DSM-IV). Clinicians and research assessors conferred concordant ED diagnoses in 80.3% of cases (kappa=0.70), thus highlighting the clinical utility of the extant DSM-IV diagnostic scheme in this specialty ED treatment setting. All but two discordant cases included a diagnosis of ED not otherwise specified (EDNOS). Clinicians applied ED subtypes in just 20.4% of eligible cases, and were significantly more likely to apply subtypes to major depressive disorder. Although clinical and research interviews yielded substantial reliability, EDNOS had the lowest reliability among the ED diagnoses. Moreover, infrequent subtype application on this specialty unit raises questions about the clinical utility of DSM-IV anorexia nervosa and bulimia nervosa subtypes, even in the context of clinically useful overarching categories.


Assuntos
Protocolos Clínicos/normas , Manual Diagnóstico e Estatístico de Transtornos Mentais , Transtornos da Alimentação e da Ingestão de Alimentos/diagnóstico , Médicos/psicologia , Adolescente , Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Maior/psicologia , Transtornos da Alimentação e da Ingestão de Alimentos/classificação , Transtornos da Alimentação e da Ingestão de Alimentos/epidemiologia , Transtornos da Alimentação e da Ingestão de Alimentos/psicologia , Feminino , Humanos , Entrevista Psicológica/métodos , Reprodutibilidade dos Testes , Adulto Jovem
8.
CNS Spectr ; 15(9): 579-586, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24790401

RESUMO

OBJECTIVES: Alterations in serotonin impact bone metabolism in animal models, and selective serotonin reuptake inhibitors (SSRI) have been associated with increased fracture risk in older adults. SSRIs are commonly used in anorexia nervosa (AN), a condition that predisposes to low bone mineral density (BMD). Our objective was to determine whether SSRI use is associated with low BMD in AN. METHODS: We examined Z-scores for spine, hip and whole body (WB) BMD, spine bone mineral apparent density and WBBMC/height (Ht) in females with AN 12-21 years old who had never been on SSRIs, on SSRIs for <6 months (<6M) or >6 months (>6M). RESULTS: Subjects on SSRIs for >6M had lower spine, femoral-neck and WBBMD Z-scores than those on SSRIs for <6M. Hip BMD and WBBMC/Ht Z-scores were lowest in subjects on SSRIs for >6M. Duration of SSRI use, duration since AN diagnosis and duration of amenorrhea inversely predicted BMD, whereas BMI was a positive predictor. In a regression model, duration of SSRI use remained an independent negative predictor of BMD. DISCUSSION: Duration of SSRI use >6M is associated with low BMD in AN. CONCLUSION: It may be necessary to monitor BMD more rigorously when duration of SSRI use exceeds 6M.

9.
Alcohol Treat Q ; 38(4): 446-456, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33727763

RESUMO

Despite the high rate of co-occurring eating disorders (EDs) and substance use disorders (SUDs) in women, there is a lack of integrated treatment. This study implemented the Women's Recovery Group (WRG), a gender-specific group therapy for women with SUDs, in an ED residential treatment program to assess the feasibility and satisfaction of the WRG for women with co-occurring SUDs and EDs. Women (N = 24) were enrolled in the study if they were aged 18 years or older and engaged in the WRG as part of their treatment. Patient and therapist satisfaction with the WRG were assessed post-treatment, and craving to use substances was measured at enrollment and post-treatment. Participants reported moderate satisfaction with the WRG, and therapists reported above average satisfaction with the WRG. Craving to use substances in the environment in which one previously used significantly decreased from enrollment to post-treatment. In its current form, the WRG was feasible to implement in ED residential treatment. Participants indicated that they would have liked more information on co-occurring EDs, self-image/self-esteem, shame and guilt, and maintaining sobriety at college. These results support the need for modifications to the WRG to better integrate treatment for women with co-occurring EDs and SUDs.

10.
Artigo em Inglês | MEDLINE | ID: mdl-31005703

RESUMO

Options for hydrophobic-interaction chromatography (HIC) for purification of cell culture-derived influenza A and B virus have been assessed using a 96-well plate format using a semi-high-throughput approach. Follow-up experiments at preparative scale were used to characterize dynamic binding capacity, viral hemagglutinin protein (HA protein) recovery, and the influence of influenza virus (IV) strains on yield and contamination levels. Virus recoveries of up to 96% with a residual DNA level of about 1.3% were achieved. To achieve DNA contamination levels required for manufacturing of influenza vaccines for human use, a purification train comprising clarification, inactivation, concentration, column-based anion-exchange chromatography (AEC), and HIC was used in a final set-up. AEC using strong quaternary ammonium ligands was applied as an orthogonal method for DNA depletion by adsorption. Subsequently, HIC (with polypropylene glycol as functional group) was used to reversibly bind virus particles for capture and to remove residual contaminating DNA and proteins (flow-through). This two-step chromatographic process, which requires neither a buffer exchange step nor nuclease treatment had a total virus particle yield for IV A/PR/8/34 (H1N1) of 92%. The protein and the DNA contamination level could be reduced to 42% and at least 1.0%, respectively. With 17.2 µg total protein and 2.0 ng DNA per monovalent dose, this purity level complies with the limits of the European Pharmacopeia for cell culture-derived human vaccines. Overall, the presented downstream process represents a valuable alternative to existing virus purification schemes. Furthermore, it utilizes only off-the-shelf materials and is a simple as well as an economic process for production of cell culture-derived viruses and viral vectors.


Assuntos
Cromatografia Líquida/métodos , Vírus da Influenza A/isolamento & purificação , Vírus da Influenza B/isolamento & purificação , Hemaglutininas Virais/análise , Hemaglutininas Virais/isolamento & purificação , Ensaios de Triagem em Larga Escala/métodos , Interações Hidrofóbicas e Hidrofílicas , Vacinas contra Influenza , Cloreto de Sódio/química , Cultura de Vírus
11.
J Biomech ; 40 Suppl 1: S80-8, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17466994

RESUMO

Cell stimulation by bioactive molecules has become an important tool in tissue engineering. The homogeneous incorporation of such molecules within the bulk of a polymer-based scaffold compared to surface coating is considered advantageous for most applications and minimizes a burst effect. An efficient way of bulk loading is the incorporation of these molecules during the scaffold formation process. In this paper, two different integrated processes for the preparation of scaffolds from poly(epsilon-caprolactone) (PCL) loaded with a small molecule are investigated. Both formation and loading of the scaffold is carried out in a single-step process. Sudan Red G was selected as a model compound for lipophilic small molecules. A freeze drying and pressure quench (PQ) formation process was selected, and the influence of the small molecule on the formation processes and on the morphology of the obtained scaffold was evaluated and compared. It could be shown for both processes that the formation of loaded scaffolds is possible, and that the small molecule has a very high impact on the foam morphology. In case of the freeze-drying (FD) method, only a load of 1 wt% Sudan Red G was incorporated within the bulk and showed no influence on the foam morphology. In the case of PQ foaming, an incorporation of 43 wt% Sudan Red G was achieved (although tiny crystal needles of the small molecule were found on the surface) and a strong effect on the foam morphology was found. This paper presents an efficient method of incorporating small molecules by integrated processes.


Assuntos
Caproatos/química , Lactonas/química , Alicerces Teciduais/química , Materiais Biocompatíveis , Liofilização , Estrutura Molecular , Polímeros
12.
J Clin Endocrinol Metab ; 102(1): 57-68, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-27732336

RESUMO

Context: Areal bone mineral density (BMD) is lower, particularly at the spine, in low-weight women with anorexia nervosa (AN). However, little is known about vertebral integral volumetric BMD (Int.vBMD) or vertebral strength across the AN weight spectrum, including "atypical" AN [body mass index (BMI) ≥18.5 kg/m2]. Objective: To investigate Int.vBMD and vertebral strength, and their determinants, across the AN weight spectrum. Design: Cross-sectional observational study. Setting: Clinical research center. Participants: 153 women (age 18 to 45): 64 with low-weight AN (BMI <18.5 kg/m2; 58% amenorrheic), 44 with atypical AN (18.5≤BMI<23 kg/m2; 30% amenorrheic), 45 eumenorrheic controls (19.2≤BMI<25 kg/m2). Measures: Int.vBMD and cross-sectional area (CSA) by quantitative computed tomography of L4; estimated vertebral strength (derived from Int.vBMD and CSA). Results: Int.vBMD and estimated vertebral strength were lowest in low-weight AN, intermediate in atypical AN, and highest in controls. CSA did not differ between groups; thus, vertebral strength (calculated using Int.vBMD and CSA) was driven by Int.vBMD. In AN, Int.vBMD and vertebral strength were associated positively with current BMI and nadir lifetime BMI (independent of current BMI). Int.vBMD and vertebral strength were lower in AN with current amenorrhea and longer lifetime amenorrhea duration. Among amenorrheic AN, Int.vBMD and vertebral strength were associated positively with testosterone. Conclusions: Int.vBMD and estimated vertebral strength (driven by Int.vBMD) are impaired across the AN weight spectrum and are associated with low BMI and endocrine dysfunction, both current and previous. Women with atypical AN experience diminished vertebral strength, partially due to prior low-weight and/or amenorrhea. Lack of current low-weight or amenorrhea in atypical AN does not preclude compromise of vertebral strength.


Assuntos
Amenorreia/fisiopatologia , Anorexia Nervosa/fisiopatologia , Peso Corporal , Densidade Óssea/fisiologia , Coluna Vertebral/fisiopatologia , Magreza/fisiopatologia , Adolescente , Adulto , Amenorreia/diagnóstico por imagem , Anorexia Nervosa/diagnóstico por imagem , Estudos de Casos e Controles , Estudos Transversais , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Prognóstico , Coluna Vertebral/diagnóstico por imagem , Magreza/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto Jovem
13.
Macromol Biosci ; 6(4): 274-84, 2006 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-16565943

RESUMO

Poly(ether imide) (PEI) membranes were modified with a linear low-molecular weight (PETIM_0.6) and a branched high-molecular weight poly(ethylene imine) (PETIM_60). The membrane surfaces became more hydrophilic and the zeta potentials were shifted from negative to positive zeta values after immobilisation of both PETIM. These measurements also indicated the presence of a swollen surface layer in the case of PETIM_60, while a regular structuring of the surface was observed with scanning force microscopy for PETIM_0.6. A human keratinocyte cell line HaCaT was cultured on the different membranes. It was found that HaCaT cell growth was stimulated by PETIM_0.6. Cells reached earlier confluence on this substratum, while their growth was inhibited on a PEI membrane modified with PETIM_60, which makes PEI membranes modified with PETIM_0.6 a promising material for in vitro culture of epidermal transplants.


Assuntos
Células Epidérmicas , Iminas/química , Membranas Artificiais , Polietilenos/química , Pele Artificial , Adulto , Divisão Celular , Linhagem Celular , Permeabilidade da Membrana Celular , Proliferação de Células , Humanos , Microscopia de Força Atômica , Microscopia Confocal
14.
Expert Rev Med Devices ; 3(6): 835-51, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17280547

RESUMO

Polymeric scaffolds for tissue engineering can be prepared with a multitude of different techniques. Many diverse approaches have recently been under development. The adaptation of conventional preparation methods, such as electrospinning, induced phase separation of polymer solutions or porogen leaching, which were developed originally for other research areas, are described. In addition, the utilization of novel fabrication techniques, such as rapid prototyping or solid free-form procedures, with their many different methods to generate or to embody scaffold structures or the usage of self-assembly systems that mimic the properties of the extracellular matrix are also described. These methods are reviewed and evaluated with specific regard to their utility in the area of tissue engineering.


Assuntos
Materiais Biocompatíveis/química , Matriz Extracelular/química , Matriz Extracelular/ultraestrutura , Polímeros/química , Engenharia Tecidual , Microesferas
15.
Polymers (Basel) ; 8(12)2016 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-30974689

RESUMO

Water-blown polyurethane (PU) foams are of enormous technological interest as they are widely applied in various fields, i.e., consumer goods, medicine, automotive or aerospace industries. The discovery of the one-way shape-memory effect in PU foams provided a fresh impetus for extensive investigations on porous polymeric actuators over the past decades. High expansion ratios during the shape-recovery are of special interest when big volume changes are required, for example to fill an aneurysm during micro-invasive surgery or save space during transportation. However, the need to program the foams before each operation cycle could be a drawback impeding the entry of shape-memory polymeric (SMP) foams to our daily life. Here, we showed that a reversible shape-memory effect (rSME) is achievable for polyurethane water-blown semicrystalline foams. We selected commercially available crystallizable poly(ε-caprolactone)-diols of different molecular weight for foams synthesis, followed by investigations of morphology, thermal, thermomechanical and shape-memory properties of obtained compositions. Densities of synthesized foams varied from 110 to 180 kg∙m-3, while peak melting temperatures were composition-dependent and changed from 36 to 47 °C, while the melting temperature interval was around 15 K. All semicrystalline foams exhibited excellent one-way SME with shape-fixity ratios slightly above 100% and shape-recovery ratios from the second cycle of 99%. The composition with broad distribution of molecular weights of poly(ε-caprolactone)-diols exhibited an rSME of about 12% upon cyclic heating and cooling from Tlow = 10 °C and Thigh = 47 °C. We anticipate that our experimental study opens a field of systematic investigation of rSMEs in porous polymeric materials on macro and micro scale and extend the application of water-blown polyurethane foams to, e.g., protective covers with zero thermal expansion or even cushions adjustable to a certain body shape.

16.
J Biotechnol ; 220: 12-20, 2016 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-26712479

RESUMO

A simple membrane-based purification process for cell culture-derived influenza virus was established that relies on only two chromatographic unit operations to achieve the contamination limits required according to regulatory authorities. After clarification and concentration, a pseudo-affinity membrane adsorber (sulfated cellulose, SCMA) was applied for virus capture. The subsequent polishing step consisted of a salt-tolerant anion exchange membrane adsorber (STMA) to bind residual DNA. For the presented process neither a buffer exchange step nor a nuclease step for further DNA digestion were required. As a starting point, a two-salt strategy (including a polyvalent ion) was employed to screen STMA conditions in a 96-well plate format. After optimization on chromatographic laboratory scale, the virus recovery was up to 97% with a residual DNA level below 0.82%. In addition, the STMA was characterized regarding its dynamic binding capacity and the impact of flow rate on yields and contamination levels. Overall, the total virus yield for influenza virus A/PR/8/34 (H1/N1) of this two-step membrane process was 75%, while the protein and the DNA contamination level could be reduced to 24% and at least 0.5%, respectively. With 19.8µg protein and 1.2ng DNA per monovalent dose, this purity level complies with the limits of the European Pharmacopeia for cell culture-derived vaccines for human use. Overall, the presented downstream process might serve as a generic and economic platform technology for production of cell culture-derived viruses and viral vectors.


Assuntos
Técnicas de Cultura de Células/métodos , Cromatografia Líquida/métodos , Vírus da Influenza A/isolamento & purificação , Virologia/métodos , Adsorção , Animais , Ânions/química , Biotecnologia/métodos , Celulose/análogos & derivados , Cromatografia Líquida/economia , Contaminação por DNA , DNA Viral/isolamento & purificação , Cães , Humanos , Vírus da Influenza A/genética , Vírus da Influenza A/imunologia , Vacinas contra Influenza/química , Vacinas contra Influenza/farmacologia , Células Madin Darby de Rim Canino , Membranas/química , Membranas/virologia , Proteínas Virais/isolamento & purificação
17.
J Bone Miner Res ; 31(2): 281-8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26332401

RESUMO

Somewhat paradoxically, fracture risk, which depends on applied loads and bone strength, is elevated in both anorexia nervosa and obesity at certain skeletal sites. Factor-of-risk (Φ), the ratio of applied load to bone strength, is a biomechanically based method to estimate fracture risk; theoretically, higher Φ reflects increased fracture risk. We estimated vertebral strength (linear combination of integral volumetric bone mineral density [Int.vBMD] and cross-sectional area from quantitative computed tomography [QCT]), vertebral compressive loads, and Φ at L4 in 176 women (65 anorexia nervosa, 45 lean controls, and 66 obese). Using biomechanical models, applied loads were estimated for: 1) standing; 2) arms flexed 90°, holding 5 kg in each hand (holding); 3) 45° trunk flexion, 5 kg in each hand (lifting); 4) 20° trunk right lateral bend, 10 kg in right hand (bending). We also investigated associations of Int.vBMD and vertebral strength with lean mass (from dual-energy X-ray absorptiometry [DXA]) and visceral adipose tissue (VAT, from QCT). Women with anorexia nervosa had lower, whereas obese women had similar, Int.vBMD and estimated vertebral strength compared with controls. Vertebral loads were highest in obesity and lowest in anorexia nervosa for standing, holding, and lifting (p < 0.0001) but were highest in anorexia nervosa for bending (p < 0.02). Obese women had highest Φ for standing and lifting, whereas women with anorexia nervosa had highest Φ for bending (p < 0.0001). Obese and anorexia nervosa subjects had higher Φ for holding than controls (p < 0.03). Int.vBMD and estimated vertebral strength were associated positively with lean mass (R = 0.28 to 0.45, p ≤ 0.0001) in all groups combined and negatively with VAT (R = -[0.36 to 0.38], p < 0.003) within the obese group. Therefore, women with anorexia nervosa had higher estimated vertebral fracture risk (Φ) for holding and bending because of inferior vertebral strength. Despite similar vertebral strength as controls, obese women had higher vertebral fracture risk for standing, holding, and lifting because of higher applied loads from higher body weight. Examining the load-to-strength ratio helps explain increased fracture risk in both low-weight and obese women.


Assuntos
Anorexia Nervosa , Densidade Óssea , Modelos Biológicos , Obesidade , Fraturas da Coluna Vertebral , Coluna Vertebral/metabolismo , Adolescente , Adulto , Anorexia Nervosa/complicações , Anorexia Nervosa/epidemiologia , Anorexia Nervosa/metabolismo , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade , Obesidade/complicações , Obesidade/epidemiologia , Obesidade/metabolismo , Fatores de Risco , Fraturas da Coluna Vertebral/epidemiologia , Fraturas da Coluna Vertebral/etiologia , Fraturas da Coluna Vertebral/metabolismo , Suporte de Carga
18.
Biomaterials ; 25(13): 2467-76, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-14751731

RESUMO

The effect of the porosity of acrylonitrile-N-vinylpyrrolidone copolymer membranes on human C3A hepatoblastoma cell adhesive interaction and functioning is investigated on four membranes with an average pore size ranging between 6 and 12 nm. Adhesion of C3A cells was quantified and characterized by studying overall cell morphology and focal adhesion formation. Cell-cell interactions were characterized by E-cadherin expression and organization. Cell growth, fibronectin synthesis and cytochrome P450 activity were estimated as criteria of functional cell activity. The results suggest that membrane porosity influences the initial cell-surface interactions since an increasing pore size augmented cell adhesion and aggregate formation. Cell growth after 7 d was diminished on membranes with an average pore size of 12 nm. The activity of P450 measured by 7-ethoxycoumarin conversion at day 7 was influenced by membrane topography representing a clear optimum in the range of 7-10 nm pore size. These results indicate that membrane porosity is a determinant for the function of hepatocytes in extracorporal liver assist devices.


Assuntos
Adesão Celular , Hepatoblastoma/patologia , Neoplasias Hepáticas/patologia , Membranas Artificiais , Polímeros , Linhagem Celular Tumoral , Sistema Enzimático do Citocromo P-450/metabolismo , Hepatoblastoma/enzimologia , Humanos , Neoplasias Hepáticas/enzimologia , Microscopia Eletrônica de Varredura
20.
J Virol Methods ; 207: 45-53, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24992667

RESUMO

Vaccination is still the most efficient measure to protect against influenza virus infections. Besides the seasonal wave of influenza, pandemic outbreaks of bird or swine flu represent a high threat to human population. With the establishment of cell culture-based processes, there is a growing demand for robust, economic and efficient downstream processes for influenza virus purification. This study focused on the development of an economic flow-through chromatographic process avoiding virus strain sensitive capture steps. Therefore, a three-step process consisting of anion exchange chromatography (AEC), Benzonase(®) treatment, and size exclusion chromatography with a ligand-activated core (LCC) was established, and tested for purification of two influenza A virus strains and one influenza B virus strain. The process resulted in high virus yields (≥68%) with protein contamination levels fulfilling requirements of the European Pharmacopeia for production of influenza vaccines for human use. DNA was depleted by ≥98.7% for all strains. The measured DNA concentrations per dose were close to the required limits of 10ng DNA per dose set by the European Pharmacopeia. In addition, the added Benzonase(®) could be successfully removed from the product fraction. Overall, the presented downstream process could potentially represent a simple, robust and economic platform technology for production of cell culture-derived influenza vaccines.


Assuntos
Cromatografia Líquida/métodos , Vírus da Influenza A/isolamento & purificação , Vírus da Influenza B/isolamento & purificação , Vacinas contra Influenza/isolamento & purificação , Tecnologia Farmacêutica/métodos , Virologia/métodos , Animais , Cromatografia Líquida/economia , Humanos , Tecnologia Farmacêutica/economia , Virologia/economia
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