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1.
BMC Gastroenterol ; 22(1): 111, 2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35260086

RESUMO

BACKGROUND: The alfapump® is an implantable class III medical device that pumps ascitic fluid from the peritoneal space to the urinary bladder from where it is excreted. The pump reduces or abrogates the need for repeated paracentesis in patients with recurrent or refractory ascites. AIMS: To improve outcomes for alfapump® implantation and pre- and post-implant patient management in both clinical trial and real-world settings by development of consensus recommendations. METHODS: The alfapump® working group consisting of hepatologists and surgeons with extensive experience in implantation of the alfapump® and patient management met on two occasions: (1) to determine the key areas where recommendations should be made; and (2) to discuss the experiences of the working group within those areas and formulate draft statements. Developed statements were submitted to the group and consensus sought on relevance and wording through a collaborative iterative approach in order to consolidate the recommendations into consensus statements. Only recommendations agreed upon unanimously were included. RESULTS: Twenty-three consensus recommendations were developed in the areas of pre-implantation procedure, (three statements), surgical implant procedure (11 statements), immediate post-implant care (three statements) and long-term management (six statements). CONCLUSIONS: The consensus statements are a valuable reference resource for physicians managing patients with the alfapump® and for those considering management strategies for patients with refractory ascites.


Assuntos
Ascite , Cirrose Hepática , Ascite/etiologia , Ascite/terapia , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/cirurgia , Paracentese , Bexiga Urinária
2.
J Chromatogr A ; 1587: 88-100, 2019 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-30580959

RESUMO

Currently, a lot of research effort in polymer analysis by liquid chromatographic techniques, including size exclusion chromatography (SEC), polymer HPLC or liquid chromatography at critical conditions, is done aiming to improve separation performance. In this study, novel gradient protocols were investigated primarily based on gradient polymer elution chromatography (GPEC). Starting with linear gradients and stepwise gradients a new periodic saw tooth gradient profile was developed and optimized. Optimum settings for the saw tooth gradient design were evaluated by design of experiments (DoE) based on Taguchi's methodology for various types of stationary phases. The gain of peak resolution was dependent on the effective gradient step height. The optimized protocol enabled high-resolution polymer HPLC (HRP-HPLC) separations with common HPLC instruments. The quality of separation was evaluated by heart-cut fraction collection of HRP-HPLC and subsequent determination of the individual fractions by SEC or MALDI-ToF mass spectrometry. Finally, different types of polymers, such as PVC, PDMS, PMMA, or PPG, were studied with the new method and a universal applicability was shown.


Assuntos
Técnicas de Química Analítica/métodos , Cromatografia Líquida de Alta Pressão , Polímeros/isolamento & purificação , Técnicas de Química Analítica/instrumentação , Espectrometria de Massas , Polímeros/química
3.
J Chromatogr A ; 1564: 214-223, 2018 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-29903470

RESUMO

The adaption of an parallel-path poly(tetrafluoroethylene)(PTFE) ICP-nebulizer to an evaporative light scattering detector (ELSD) was realized. This was done by substituting the originally installed concentric glass nebulizer of the ELSD. The performance of both nebulizers was compared regarding nebulizer temperature, evaporator temperature, flow rate of nebulizing gas and flow rate of mobile phase of different solvents using caffeine and poly(dimethylsiloxane) (PDMS) as analytes. Both nebulizers showed similar performances but for the parallel-path PTFE nebulizer the performance was considerably better at low LC flow rates and the nebulizer lifetime was substantially increased. In general, for both nebulizers the highest sensitivity was obtained by applying the lowest possible evaporator temperature in combination with the highest possible nebulizer temperature at preferably low gas flow rates. Besides the optimization of detector parameters, response factors for various PDMS oligomers were determined and the dependency of the detector signal on molar mass of the analytes was studied. The significant improvement regarding long-term stability made the modified ELSD much more robust and saved time and money by reducing the maintenance efforts. Thus, especially in polymer HPLC, associated with a complex matrix situation, the PTFE-based parallel-path nebulizer exhibits attractive characteristics for analytical studies of polymers.


Assuntos
Dimetilpolisiloxanos/química , Luz , Nebulizadores e Vaporizadores , Politetrafluoretileno/química , Espalhamento de Radiação , Cafeína/análise , Calibragem , Peso Molecular , Temperatura , Viscosidade , Volatilização
4.
Neuropsychiatr Dis Treat ; 13: 2945­2953, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29263671

RESUMO

Background: Verbal memory impairment is a core feature in schizophrenia even at early stages of the disease, but its etiopathogenesis is not fully understood. The APOE-ε4 is the main genetic risk factor for late-onset Alzheimer's disease. Our primary goal was to ascertain whether APOE-ε4 status had a pleiotropic effect in early stages of the illness. Participants and methods: A total of 86 first-episode psychosis (FEP) outpatients and 39 healthy volunteers were recruited. Demographic and clinical data, APOE genotyping, and a neuropsychological test battery including the California Verbal Learning Test - second edition (CVLT-II) were administered and assessed at study entry and at 1-year follow-up. Data were analyzed using mixed-model repeated measures, where the dependent variable was verbal memory indexed by California Verbal Learning Test (CVLT) Trials 1-5 total recall score. Results: FEP-APOE-ε4 carriers and FEP-APOE-ε4 noncarriers had similar symptom severity, clinical outcomes, premorbid and current intelligence quotient, and exposure to antipsychotics. There was a main effect of group on CVLT 1-5 (FEP =43.30 vs control =58.25; F[1, 119.7]=42.97; P<0.001) as well as an APOE-ε4 by group by time (F[4, 116.2]=2.73, P=0.033) interaction with only FEP-APOE-ε4 carriers showing improved verbal memory at follow-up. Conclusion: Our study is the first to report improvement in verbal memory in persons afflicted by FEP who are APOE-ε4 carriers and replicates the prominent verbal memory deficits present in FEP. Our work provides further evidence pointing to an antagonistic pleiotropic effect of APOE-ε4 in neuropsychiatric disorders. Our results merit further research into antagonistic pleiotropic effects in schizophrenia.

5.
Schizophr Res ; 134(2-3): 253-9, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22192502

RESUMO

INTRODUCTION: Small hippocampi and impaired memory are common in patients with psychosis and brain-derived neurotrophic factor (BDNF) plays a critical role in hippocampal neuroplasticity and memory. A common BDNF allele (Val66Met) has been the focus of numerous studies but results from the few BDNF-imaging studies are complex and contradictory. The objective of this study was to determine the association between Val66Met and hippocampal volume in patients with first episode psychosis. Secondary analyses explored age-related associations and the relationship between Val66Met and memory. METHOD: Hippocampal volume and BDNF genotyping were obtained for 58 patients with first-episode psychosis and 39 healthy volunteers. Patients were recruited from an early psychosis program serving a catchment-area population. RESULTS: Hippocampal volume was significantly smaller in patients than controls (F(1,92)=4.03, p<0.05) and there was a significant group-by-allele interaction (F(1,92)=3.99, p<0.05). Hippocampal volume was significantly smaller in patients than controls who were Val-homozygotes but no group differences were found for Met carriers. Findings were not affected by diagnosis, antipsychotic medication, or age, and there was no change in hippocampal volume during a one-year follow-up. Val-homozygous patients had worse immediate and delayed memory than their Met counterparts. CONCLUSIONS: Results suggest the effects of the BDNF Val66Met allele may be different in patients with psychosis than in healthy adults. Hippocampal volume in patient and control Met allele carriers was very similar suggesting that illness-related factors have minimal influence in this group. In contrast, Val homozygosity was related to smaller hippocampi and poorer memory functioning only in patients with psychosis.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/genética , Predisposição Genética para Doença/genética , Hipocampo/patologia , Polimorfismo de Nucleotídeo Único/genética , Transtornos Psicóticos/genética , Transtornos Psicóticos/patologia , Adolescente , Adulto , Fatores Etários , Análise de Variância , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/genética , Transtornos Cognitivos/patologia , Feminino , Estudos de Associação Genética , Genótipo , Humanos , Imageamento por Ressonância Magnética , Masculino , Memória , Metionina/genética , Testes Neuropsicológicos , Transtornos Psicóticos/complicações , Valina/genética , Adulto Jovem
6.
Saudi J Anaesth ; 5(1): 101-4, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21655031

RESUMO

We report on a patient with acute intermittent porphyria, who received 8 AB0 incompatible units of packed red blood cells in an emergency situation. She never showed any signs of severe intravascular haemolysis. The patient died after four weeks because of a multi-organ failure caused from the malpractice of the porphyria. The problems of bedside testing, mixing field reaction, fresh frozen plasma and molecular-genetic determination of bloodgroup were discussed.

7.
Psychiatr Serv ; 62(4): 411-7, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21459993

RESUMO

OBJECTIVE: The Global Assessment of Functioning scale (GAF) is included as axis V in the DSM-IV multiaxial diagnostic system. The GAF is simple to administer and routinely used in treatment planning and as a measure of program performance. The GAF assesses both symptom severity and functional impairment, but the resultant rating provides no information about the contribution of each of these domains. This study aimed to improve the clinical utility of the GAF by creating subscales. METHODS: The authors divided the scale into its two principal domains: descriptors of social and occupational functioning (SOFAS) and descriptors of symptoms (GAF minus SOFAS descriptors). These and other measures of symptoms and functioning were used to assess 407 patients while acutely psychotic and again after treatment. RESULTS: Symptom scores were of greater severity than functional impairment scores in most cases. Because of this, the GAF score tended to reflect symptom severity rather than functional impairment. The symptom rating was more strongly correlated with measures of positive symptoms, and the functional rating had higher associations with negative symptoms and functional impairment. Both scales were good indicators of clinical change. CONCLUSIONS: Findings indicate that GAF ratings for patients with psychosis tend to reflect symptom severity rather than functional impairment. Splitting the GAF into two parts resulted in greater discrimination for this patient group yet retained ease of administration.


Assuntos
Atividades Cotidianas/psicologia , Escalas de Graduação Psiquiátrica Breve , Manual Diagnóstico e Estatístico de Transtornos Mentais , Transtornos Mentais/fisiopatologia , Índice de Gravidade de Doença , Adolescente , Adulto , Escalas de Graduação Psiquiátrica Breve/normas , Feminino , Humanos , Masculino , Transtornos Mentais/diagnóstico , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem
8.
Anal Chem ; 82(19): 8169-75, 2010 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-20879802

RESUMO

In recent years, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has become a powerful tool for the study of synthetic polymers although its mechanism is still not understood in detail. Sample preparation plays the key role in obtaining reliable MALDI mass spectra, in particular, the proper choice of matrix, cationization reagent, and solvent. There is still no general sample preparation protocol for MALDI analysis of synthetic polymers. For known synthetic polymers, such as polystyrenes and other frequently investigated polymers, application tables in review articles might be a guide for selecting a MALDI matrix, cationization reagent, and solvent. For unknown polymers (polymers which were not analyzed by MALDI-TOF MS before but whose structures are in part known from the manufacturing process and from NMR analysis as well), the selection of matrix and solvent is based upon the polarity-similarity principle. Chemometric methods provide a useful tool for the investigation of sample preparation because huge data sets can be evaluated in short time, that is, for extracting relevant information and for classification of samples, as well. Furthermore, chemometrics provide a suitable way for the selection of a proper matrix, cationization reagent, and solvent. In this paper, a prediction model is presented using the partial least-squares (PLS) regression. By applying the model, the suitability of appropriate (nontested) combinations (matrix, cationization reagent, solvent) can be predicted for a certain synthetic polymer based upon the investigation of a few combinations. This model may help find suitable combinations in a short time and serve as a starting point for the investigation of unknown polymers. Results are exemplary presented for polystyrene PS2850.

9.
J Am Soc Mass Spectrom ; 21(11): 1870-5, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20685132

RESUMO

It is well known that the mixing ratio affects the molar mass distribution of synthetic polymers determined by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Surely, the molar mixing ratio determines whether a mass spectrum will be obtained or not. However, depending on the mass range, several effects such as multimer formation occur, which might be a source of errors in molar mass distribution calculations. In this study, the effect of mixing ratio was investigated for several synthetic polymers, including polystyrene (PS), poly(dimethylsiloxane) (PDMS), poly(ethylene glycol) (PEG), and poly(methyl methacrylate) (PMMA) using statistical designs of experiments. The 2(3) full factorial design was found to be suitable in the study of more than 1000 samples. The obtained MALDI mass spectra as well as the ANOVA statistics show that the mixing ratio affects the molar mass distribution. The optimal mixing ratio for a defined synthetic polymer depends on the studied combination (matrix, cationization reagent, solvent).

10.
Rapid Commun Mass Spectrom ; 24(16): 2439-44, 2010 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-20658683

RESUMO

The principle relating to the selection of a proper matrix, cationization reagent, and solvent for matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) of synthetic polymers is still a topic of research. In this work we focused on the selection of a suitable MALDI solvent. Polystyrene PS7600 and poly(ethylene glycol) PEG4820 were analyzed by MALDI-TOF MS using various solvents which were selected based on the Hansen solubility parameter system. For polystyrene (PS), dithranol was used as the matrix and silver trifluoroacetate as the cationization reagent whereas, for poly(ethylene glycol) (PEG), the combination of 2,5-dihydroxybenzoic acid and sodium trifluoroacetate was used for all experiments. When employing solvents which dissolve PS and PEG, reliable MALDI mass spectra were obtained while samples in non-solvents (solvents which are not able to dissolve the polymer) failed to provide spectra. It seems that the solubility of the matrix and the cationization reagent are less important than the polymer solubility.

12.
Schizophr Res ; 108(1-3): 258-64, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19162444

RESUMO

INTRODUCTION: Cigarette smoking is common in psychotic disorders and may be initiated in an attempt to control features of illness. However, genetic, obstetric and early life conditions are risks for starting to smoke in the general population but their role in psychotic patients is unclear. METHOD: Smoking history and the putative predictors of starting to smoke were assessed in a community-wide sample of 115 first episode psychosis patients. The proportion that initiated smoking was compared with that from population surveys and the impact of risk factors was assessed within the patient sample. RESULTS: Most patients began smoking before illness onset and the proportion who initiated smoking was significantly high by the onset of a functional decline. Gestational tobacco exposure was a risk for smoking and was also associated with low birthweight, poor academic achievement, and obesity. Low familial socioeconomic position but not familial psychiatric problems also predicted smoking initiation. DISCUSSION: In most cases, smoking preceded illness onset and was not a response to early features of illness. General population predictors of starting to smoke were also associated with smoking initiation in psychotic patients. Of these risks, exposure to tobacco during gestation is noteworthy in that it affects brain development and is associated with cognitive, behavioral, psychiatric and general health problems. In addition, nicotine interacts with other substances of abuse. The initiation of smoking before illness onset and the association with developmental problems raises the question of whether cigarette smoking influences some aspects of illness in patients with psychosis.


Assuntos
Transtornos Psicóticos/psicologia , Fumar/epidemiologia , Fumar/psicologia , Adolescente , Adulto , Idade de Início , Escolaridade , Saúde da Família , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Gravidez , Complicações na Gravidez , Prevalência , Estudos Retrospectivos , Fatores de Risco , Fatores Socioeconômicos , Adulto Jovem
13.
Compr Psychiatry ; 48(6): 597-604, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17954147

RESUMO

UNLABELLED: This study examined the reliability and validity of a brief, face-valid self-report measure designed to assess subjective judgments of functioning. The Patient Perception of Functioning Scale (PPFS) is a 6-item scale with ratings for both community functioning and cognition. METHOD: Sixty-eight subjects with psychotic disorders were recruited to complete the PPFS on 2 occasions and to complete a battery of neurocognitive tests. Objective ratings of overall illness severity (Clinical Global Impression), illness severity (Global Assessment of Functioning), and functioning (Social and Occupational Functioning Assessment Scale and Role Functioning Scale) were also obtained. RESULTS: The internal consistency and test-retest correlation coefficients revealed that the PPFS possesses good reliability characteristics. The PPFS did not show relationships to demographic, historical, or illness-related variables such as diagnosis or length of illness. The PPFS did show significant associations with several dimensions of community functioning. However, no significant associations were found with neurocognitive measures or clinical status. CONCLUSIONS: In populations with psychotic disorders, self-reported ratings of community function and cognition may converge less with objective cognitive measures than with objective ratings of everyday functioning. Several factors inherent to self-report methodology may have contributed to the poor convergent validity results. Theoretical underpinnings and operationalization of the underlying constructs of some neuropsychological instruments may not closely match how patients conceptualize those constructs.


Assuntos
Cognição , Testes Neuropsicológicos , Transtornos Psicóticos/psicologia , Autoavaliação (Psicologia) , Adulto , Feminino , Humanos , Masculino , Escalas de Graduação Psiquiátrica , Reprodutibilidade dos Testes , Índice de Gravidade de Doença
14.
Psychiatry ; 69(1): 47-68, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16704332

RESUMO

Over the past few decades, there has been increasing interest in the study of social impairment in schizophrenia. However, the concept of social functioning has been poorly defined in the literature. This article highlights the global and multi-factorial nature of social functioning and reviews the theoretical determinants of social dysfunction in schizophrenia. Emphasis is placed on outlining the social cognitive deficits that may occur. The study of social cognition appears particularly promising in elucidating our understanding of the development of social impairment in schizophrenia and has the potential to improve current psychosocial interventions. However, continued advances depend upon the existence of reliable and well-validated measures of social functioning and social cognition. A selection of measures are reviewed in this article in an attempt to highlight the importance of assessing multiple aspects of social functioning in schizophrenia and to assist researchers in the selection of appropriate measures. Future efforts should be directed towards the continued validation of social functioning and social cognitive measures and their adaptation for use in at-risk and early psychosis populations.


Assuntos
Cognição , Esquizofrenia , Psicologia do Esquizofrênico , Comportamento Social , Percepção Social , Atitude Frente a Saúde , Humanos , Psicologia
15.
J Chromatogr A ; 995(1-2): 217-26, 2003 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-12800938

RESUMO

For the determination of inorganic and organic anions, the pyromellitic acid (PMA) electrolyte is widely used. The pH adjustment of the self-prepared electrolyte was very challenging to satisfy the pH of specification of pH 7.8 +/- 0.1. A modification was proposed to provide a more simple electrolyte by buffering the PMA electrolyte with triethanolamine (TEA) only instead of adjusting the pH by NaOH and TEA. Thus, the proposed electrolyte consisted of 2.25 mmol l(-1) PMA, 0.75 mmol 1(-1) hexamethonium hydroxide and 12 mmol 1(-1) TEA. The performance of the PMA electrolyte buffered by TEA only was compared to a commercial available PMA and statistically validated in accordance with the methodology of Taguchi. No statistically significant difference could be found for both electrolytes assessing the performance and detection limits of hydrodynamic, stacking and electrokinetic injection with transient isotachophoretic preconcentration as well as repeatability of migration times, peak resolutions and peak symmetries.


Assuntos
Benzoatos/análise , Eletroforese Capilar/métodos , Eletrólitos
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