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1.
Int J Food Microbiol ; 325: 108625, 2020 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-32361052

RESUMO

Infection with the hepatitis E virus (HEV) can cause acute and chronic hepatitis in humans. The zoonotic HEV genotype 3 is mainly transmitted by consumption of raw and fermented meat products prepared from infected pigs or wild boars. Lowering of pH during fermentation is one of the microbiological hurdles considered to inhibit growth of certain pathogens. However, no data are currently available on pH stability of HEV. As a reliable and reproducible measurement of HEV infectivity in meat products is not established so far, the stability of the cell culture-adapted HEV genotype 3 strain 47832c was analyzed here in phosphate-buffered saline (PBS) at different pH values. Only a minimal decrease of infectivity (up to 0.6 log10 focus forming units) was found after treatment at pH 2 to 9 for 3 h at room temperature. At pH 10, a decrease of about 3 log10 was evident, whereas no remaining virus (>3.5 log10 decrease) was detected at pH 1. The conditions usually achieved during curing of raw sausages were simulated using D/L-lactic acid added to PBS resulting in pH 4.5 to 6.5. After incubation at 4 °C for 7 days at these conditions, no significant differences as compared to a standard PBS solution at pH 7.7 were evident. At room temperature, a 0.8 log10 decrease was found at pH 4.7 after 7 days incubation compared to pH 7.7, but less at the other pH values. In conclusion, only minimal inactivating effects were found at pH conditions commonly occurring during food processing. Therefore, remaining infectious virus might be present in fermented meat products if HEV-contaminated starting material was used. Additional effects of other factors like high salt concentrations and low aw values should be investigated in future studies.


Assuntos
Vírus da Hepatite E/crescimento & desenvolvimento , Ácido Láctico/farmacologia , Produtos da Carne/virologia , Inativação de Vírus/efeitos dos fármacos , Animais , Hepatite E/virologia , Vírus da Hepatite E/genética , Humanos , Concentração de Íons de Hidrogênio , Sus scrofa , Suínos
2.
Water Sci Technol ; 76(7-8): 1770-1780, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28991792

RESUMO

For chemically enhanced primary treatment (CEPT) with microsieving, a feedback proportional integral controller combined with a feedforward compensator was used in large pilot scale to control effluent water turbidity to desired set points. The effluent water turbidity from the microsieve was maintained at various set points in the range 12-80 NTU basically independent for a number of studied variations in influent flow rate and influent wastewater compositions. Effluent turbidity was highly correlated with effluent chemical oxygen demand (COD). Thus, for CEPT based on microsieving, controlling the removal of COD was possible. Thereby incoming carbon can be optimally distributed between biological nitrogen removal and anaerobic digestion for biogas production. The presented method is based on common automation and control strategies; therefore fine tuning and optimization for specific requirements are simplified compared to model-based dosing control.


Assuntos
Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Poluentes Químicos da Água/química , Análise da Demanda Biológica de Oxigênio , Carbono , Nitrogênio/química
3.
Herz ; 42(7): 653-661, 2017 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-28801688

RESUMO

Functional tricuspid valve (TV) regurgitation secondary to left heart disease (e.g. mitral insufficiency and stenosis) is observed in 75% of the patients with TV regurgitation and is thus the most common etiology; therefore, the majority of patients who require TV surgery, undergo concomitant mitral and/or aortic valve surgery. Uncorrected moderate and severe TV regurgitation may persist or even worsen after mitral valve surgery, leading to progressive heart failure and death. Patients with moderate to severe TV regurgitation show a 3-year survival rate of 40%. Surgery is indicated in patients with severe TV regurgitation undergoing left-sided valve surgery and in patients with severe isolated primary regurgitation without severe right ventricular (RV) dysfunction. For patients requiring mitral valve surgery, tricuspid valve annuloplasty should be considered even in the absence of significant regurgitation, when severe annular dilatation (≥40 mm or >21 mm/m2) is present. Functional TV regurgitation is primarily treated with valve reconstruction which carries a lower perioperative risk than valve replacement. Valve replacement is rarely required. Tricuspid valve repair with ring annuloplasty is associated with better survival and a lower reoperation rate than suture annuloplasty. Long-term results are not available. The severity of the heart insufficiency and comorbidities (e.g. renal failure and liver dysfunction) are the essential determinants of operative mortality and long-term survival. Tricuspid valve reoperations are rarely necessary and associated with a considerable mortality.


Assuntos
Anuloplastia da Valva Cardíaca/métodos , Insuficiência da Valva Mitral/cirurgia , Insuficiência da Valva Tricúspide/cirurgia , Bioprótese , Parada Cardíaca Induzida , Implante de Prótese de Valva Cardíaca/métodos , Humanos , Insuficiência da Valva Mitral/mortalidade , Complicações Pós-Operatórias/mortalidade , Recidiva , Reoperação/métodos , Fatores de Risco , Esternotomia , Taxa de Sobrevida , Técnicas de Sutura , Toracotomia , Valva Tricúspide/cirurgia , Insuficiência da Valva Tricúspide/mortalidade
4.
Nervenarzt ; 88(10): 1168-1176, 2017 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-28382486

RESUMO

BACKGROUND: Almost 260,000 people in Germany suffer from a stroke each year. As a consequence, for more than 60% this leads to dysphagia. In order to prevent secondary diseases, such as pneumonia, malnutrition and dehydration, a differentiated diagnosis by a multiprofessional team in a stroke unit is required. The guidelines in 2015 for diagnosing neurologic dysphagia by the German Society of Neurology recommend a detailed anamnesis, a standardized screening, a clinical swallowing examination and additional instrumental diagnostics. OBJECTIVE: This study examined whether dysphagia is diagnosed by speech therapists at certified stroke units according to the recommended guidelines. MATERIAL AND METHODS: An online questionnaire was compiled and sent to 1 speech therapist at each of the 195 certified stoke units and 112 participants responded to the questionnaire. The questionnaire consisted of questions about anamnesis, clinical swallowing diagnostics and the instrumental diagnostics. Of the speech therapists working on a stroke unit 57% participated in this study. RESULTS: The results show that 50% of the participants elaborated a detailed and differentiated anamnesis, 64% used a standardized screening (Daniels test) and 66% implemented a guideline conform swallowing test. As technical instruments, 35% of the respondents used video fluoroscopy and 71% of the respondents a fiber endoscopy. CONCLUSION: The implementation of a detailed and differentiated anamnesis, standardized screening, and a clinical swallowing examination with testing of different food consistencies suggests a high quality of the dysphagia diagnostics at stroke units in Germany. The increasing availability of technical instruments, especially fiber endoscopy, substantiates this view.


Assuntos
Transtornos de Deglutição/diagnóstico , Transtornos de Deglutição/etiologia , Fidelidade a Diretrizes , Unidades Hospitalares , Fonoterapia , Acidente Vascular Cerebral/diagnóstico , Diagnóstico Diferencial , Endoscopia , Alemanha , Inquéritos Epidemiológicos , Humanos , Comunicação Interdisciplinar , Colaboração Intersetorial , Programas de Rastreamento , Anamnese
5.
Sci Rep ; 6: 25501, 2016 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-27195518

RESUMO

After the dispersal of modern humans (Homo sapiens) Out of Africa, hominins with a similar morphology to that of present-day humans initiated the gradual demographic expansion into Eurasia. The mitogenome (33-fold coverage) of the Pestera Muierii 1 individual (PM1) from Romania (35 ky cal BP) we present in this article corresponds fully to Homo sapiens, whilst exhibiting a mosaic of morphological features related to both modern humans and Neandertals. We have identified the PM1 mitogenome as a basal haplogroup U6*, not previously found in any ancient or present-day humans. The derived U6 haplotypes are predominantly found in present-day North-Western African populations. Concomitantly, those found in Europe have been attributed to recent gene-flow from North Africa. The presence of the basal haplogroup U6* in South East Europe (Romania) at 35 ky BP confirms a Eurasian origin of the U6 mitochondrial lineage. Consequently, we propose that the PM1 lineage is an offshoot to South East Europe that can be traced to the Early Upper Paleolithic back migration from Western Asia to North Africa, during which the U6 lineage diversified, until the emergence of the present-day U6 African lineages.


Assuntos
Fluxo Gênico , Genética Populacional , Genoma Mitocondrial , Migração Humana , África , Antropologia Física , Europa (Continente) , Genes Mitocondriais , Humanos , Filogenia , Filogeografia
6.
Commun Agric Appl Biol Sci ; 80(3): 579-82, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-27141756

RESUMO

Mathematical models on properties and behavior of harmful organisms in the food chain are an increas- ingly relevant approach of the agriculture and food industry. As a consequence, there are many efforts to develop biological models in science, economics and risk assessment nowadays. However, there is a lack of international harmonized standards on model annotation and model formats, which would be neces- sary to set up efficient tools supporting broad model application and information exchange. There are some established standards in the field of systems biology, but there is currently no corresponding provi- sion in the area of plant protection. This work therefore aimed at the development of an annotation scheme using domain-specific metadata. The proposed scheme has been validated in a prototype implementation of a web-database model repository. This prototypic community resource currently contains models on aflatoxin secreting fungal Aspergillus flavus in maize, as these models have a high relevance to food safety and economic impact. Specifically, models describing biological processes of the fungus (growth, Aflatoxin secreting), as well as dose-response- and carry over models were included. Furthermore, phenological models for maize were integrated as well. The developed annotation scheme is based on the well-established data exchange format SBML, which is broadly applied in the field of systems biology. The identified example models were annotated according to the developed scheme and entered into a Web-table (Google Sheets), which was transferred to a web based demonstrator available at https://sites.google.com/site/test782726372685/. By implementation of a software demonstrator it became clear that the proposed annotation scheme can be applied to models on plant pathogens and that broad adoption within the domain could promote communication and application of mathematical models.


Assuntos
Doenças das Plantas/prevenção & controle , Modelos Biológicos , Modelos Teóricos , Doenças das Plantas/microbiologia , Software
7.
Waste Manag ; 34(4): 780-90, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24529793

RESUMO

Leachate recirculation is a key process in the operation of municipal waste landfills as bioreactors. To quantify the water content and to evaluate the leachate injection system, in situ methods are required to obtain spatially distributed information, usually electrical resistivity tomography (ERT). However, this method can present false variations in the observations due to several parameters. This study investigates the impact of the geomembrane on ERT measurements. Indeed, the geomembrane tends to be ignored in the inversion process in most previously conducted studies. The presence of the geomembrane can change the boundary conditions of the inversion models, which have classically infinite boundary conditions. Using a numerical modelling approach, the authors demonstrate that a minimum distance is required between the electrode line and the geomembrane to satisfy the good conditions of use of the classical inversion tools. This distance is a function of the electrode line length (i.e. of the unit electrode spacing) used, the array type and the orientation of the electrode line. Moreover, this study shows that if this criterion on the minimum distance is not satisfied, it is possible to significantly improve the inversion process by introducing the complex geometry and the geomembrane location into the inversion tools. These results are finally validated on a field data set gathered on a small municipal solid waste landfill cell where this minimum distance criterion cannot be satisfied.


Assuntos
Gerenciamento de Resíduos , Reatores Biológicos , Impedância Elétrica , Água/análise
8.
Waste Manag ; 30(3): 452-64, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19913401

RESUMO

Leachate recirculation is a key process in the scope of operating municipal waste landfills as bioreactors, which aims to increase the moisture content to optimize the biodegradation in landfills. Given that liquid flows exhibit a complex behaviour in very heterogeneous porous media, in situ monitoring methods are required. Surface time-lapse electrical resistivity tomography (ERT) is usually proposed. Using numerical modelling with typical 2D and 3D injection plume patterns and 2D and 3D inversion codes, we show that wrong changes of resistivity can be calculated at depth if standard parameters are used for time-lapse ERT inversion. Major artefacts typically exhibit significant increases of resistivity (more than +30%) which can be misinterpreted as gas migration within the waste. In order to eliminate these artefacts, we tested an advanced time-lapse ERT procedure that includes (i) two advanced inversion tools and (ii) two alternative array geometries. The first advanced tool uses invariant regions in the model. The second advanced tool uses an inversion with a "minimum length" constraint. The alternative arrays focus on (i) a pole-dipole array (2D case), and (ii) a star array (3D case). The results show that these two advanced inversion tools and the two alternative arrays remove almost completely the artefacts within +/-5% both for 2D and 3D situations. As a field application, time-lapse ERT is applied using the star array during a 3D leachate injection in a non-hazardous municipal waste landfill. To evaluate the robustness of the two advanced tools, a synthetic model including both true decrease and increase of resistivity is built. The advanced time-lapse ERT procedure eliminates unwanted artefacts, while keeping a satisfactory image of true resistivity variations. This study demonstrates that significant and robust improvements can be obtained for time-lapse ERT monitoring of leachate recirculation in waste landfills.


Assuntos
Monitoramento Ambiental/métodos , Biodegradação Ambiental , Reatores Biológicos , Conservação dos Recursos Naturais/métodos , Eletricidade , Eletroquímica/métodos , Eletrodos , Desenho de Equipamento , Imageamento Tridimensional , Eliminação de Resíduos/métodos , Fatores de Tempo , Gerenciamento de Resíduos/métodos
9.
Neurol Res ; 32(4): 421-4, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19660182

RESUMO

OBJECTIVE: Despite the relatively high incidence of the thoracic outlet syndrome, diagnostic criteria, role of surgery and optimal operative approach remain controversial. The main goal of the current study is to determine the long-term outcome of operative treatment of a series of patients with non-specific neurogenic thoracic outlet syndrome. METHODS: A retrospective study of a consecutive group of patients with thoracic outlet syndrome was carried out. The indications for surgery relied on clinical examination. Patients with diffuse pain were excluded. In all cases, the supraclavicular approach was used. Main outcome measures were neurological status and subjective complains. RESULTS: Nineteen patients have been operated over a period of 5 years. Total number of surgeries was 23. Pain and paresthesia on exertion were the leading symptoms in all cases. The causes of thoracic outlet syndrome were fibromuscular compression in 43.5%, cervical rib alone or in combination with a fibromuscular component in 30.4% and the first rib in 26.1%. The average follow-up was 36.3 months. In 91.7%, improvement of at least 50% was observed; 20.8% of the patients were completely symptom-free, and in 25%, the improvement was 90%. Recovery of the pre-operative motor weakness was recorded in 66.6%. The mortality and the permanent morbidity rates of the procedure were 0%. DISCUSSION: Operative decompression of the brachial plexus via the supraclavicular approach in patients with non-specific neurogenic thoracic outlet syndrome is a safe procedure that leads to a significant neurological improvement and amelioration of complains. The indication for surgery should be based chiefly on the neurological and clinical findings.


Assuntos
Neuropatias do Plexo Braquial/cirurgia , Descompressão Cirúrgica/métodos , Procedimentos Neurocirúrgicos/métodos , Cavidade Torácica/cirurgia , Síndrome do Desfiladeiro Torácico/cirurgia , Adulto , Neuropatias do Plexo Braquial/patologia , Neuropatias do Plexo Braquial/fisiopatologia , Síndrome da Costela Cervical/patologia , Síndrome da Costela Cervical/fisiopatologia , Síndrome da Costela Cervical/cirurgia , Descompressão Cirúrgica/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Debilidade Muscular/etiologia , Debilidade Muscular/fisiopatologia , Debilidade Muscular/cirurgia , Procedimentos Neurocirúrgicos/estatística & dados numéricos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/fisiopatologia , Estudos Retrospectivos , Cavidade Torácica/patologia , Cavidade Torácica/fisiopatologia , Síndrome do Desfiladeiro Torácico/patologia , Síndrome do Desfiladeiro Torácico/fisiopatologia , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
10.
Med Biol Eng Comput ; 46(11): 1085-95, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18810521

RESUMO

Diagnosis of vascular disease and selection and planning of therapy are to a large extent based on the geometry of the diseased vessel. Treatment of a particular vascular disease is usually considered if the geometrical parameter that characterizes the severity of the disease, e.g. % vessel narrowing, exceeds a threshold. The thresholds that are used in clinical practice are based on epidemiological knowledge, which has been obtained by clinical studies including large numbers of patients. They may apply "on average", but they can be sub-optimal for individual patients. To realize more patient-specific treatment decision criteria, more detailed knowledge may be required about the vascular hemodynamics, i.e. the blood flow and pressure in the diseased vessel and the biomechanical reaction of the vessel wall to this flow and pressure. Over the last decade, a substantial number of publications have appeared on hemodynamic modeling. Some studies have provided first evidence that this modeling may indeed be used to support therapeutic decisions. The goal of the research reported in this paper is to go one step further, namely to investigate the feasibility of a patient-specific hemodynamic modeling methodology that is not only effective (improves therapeutic decisions), but that is also efficient (easy to use, fast, as much as possible automatic) and robust (insensitive to variation in the quality of the input data, same outcome for different users). A review is presented of our research performed during the last 5 years and the results that were achieved. This research focused on the risk assessment for one particular disease, namely abdominal aortic aneurysm, a life-threatening dilatation of the abdominal aorta.


Assuntos
Aneurisma da Aorta Abdominal/diagnóstico , Modelos Cardiovasculares , Medição de Risco/métodos , Simulação por Computador , Estudos de Viabilidade , Hemodinâmica , Hemorreologia , Humanos , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X
11.
Br J Surg ; 95(6): 765-9, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18418860

RESUMO

BACKGROUND: Ileoanal pouch polyps commonly develop following restorative proctocolectomy in patients with familial adenomatous polyposis (FAP). In FAP adenomas, the relationship between germline and somatic adenomatous polyposis coli (APC) mutations is determined by 'just right' beta-catenin signalling in tumour cells, with respect to the 20-amino acid beta-catenin-binding/degradation repeats (20AARs) in the APC protein. However, the relationship varies, with upper gastrointestinal polyps typically retaining three to four 20AARs and colonic polyps retaining one or two. The aim of this study was to establish the mutational spectrum in ileoanal pouch polyps, to ascertain whether polyp development resembled that typical of small or large bowel. METHODS: Some 151 pouch adenomas were screened from 46 patients with known germline APC mutations for 'second hits' acquired through loss of heterozygosity and truncating mutations. The number of 20AARs remaining after the 'second hit' was calculated. RESULTS: Loss of heterozygosity was rare in pouch polyps except when the germline mutation left one 20AAR. Overall, the combined alleles left two to three 20AARs in 40 of 51 polyps with an identified 'second hit'. This was significantly fewer than in upper gastrointestinal polyps, and more than in colorectal adenomas. CONCLUSION: Tissue environment appears to influence the position of the 'second hit' in pouch polyps and the mutations resemble those of large bowel polyps.


Assuntos
Polipose Adenomatosa do Colo/genética , Bolsas Cólicas , Genes APC , Mutação em Linhagem Germinativa/genética , Pólipos Intestinais/genética , Polipose Adenomatosa do Colo/cirurgia , Adulto , Idoso , Feminino , Humanos , Perda de Heterozigosidade , Masculino , Pessoa de Meia-Idade , Proctocolectomia Restauradora
12.
J Neural Transm (Vienna) ; 115(2): 191-200, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-17896073

RESUMO

Although the coexistence of attention-deficit/hyperactivity disorder (ADHD) and tic disorder (TD) is common, the nature of association is yet not fully understood. Thus, the aim of the present study was to explore attentional dysfunction in children with pure ADHD compared to children with comorbid ADHD + TD. Three groups of 20 children each, aged 8-15 years with either ADHD, ADHD + chronic tic disorder or Tourette syndrome (ADHD + TD) and a healthy control group were compared in their performance on three computerized attention tasks. Tasks of sustained attention, selective attention and interference control were employed. In addition, parental ratings of ADHD symptom severity and behaviour problems were obtained. Both clinical groups were rated as equally inattentive, however, externalising symptoms were more severe in the ADHD group. Objective measures of attentional performance revealed differences between the groups: whereas the ADHD group was markedly impaired in sustaining attention and selective attention/inhibitory control, the ADHD + TD group only showed marginal deficits in selective attention/inhibitory control. Possible explanations for the superior performance of the comorbid group are discussed: In particular, the results may indicate that in some patients, the tic disorder produces behavioural symptoms of ADHD, but not the broad neurocognitive deficits that usually are associated with ADHD. Alternatively, compensatory neural mechanisms of TD patients may result in a better neuropsychological performance of comorbid patients relative to patients suffering from pure ADHD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/complicações , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Atenção/fisiologia , Transtornos de Tique/complicações , Transtornos de Tique/epidemiologia , Adolescente , Criança , Comportamento de Escolha/fisiologia , Feminino , Humanos , Inteligência , Masculino , Análise Multivariada , Testes Neuropsicológicos , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia
13.
Magnes Res ; 19(3): 190-8, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17172009

RESUMO

Mg2+ efflux from erythrocytes can be performed by the Na+/Mg2+ antiport and by Na+-independent Mg2+ efflux. Na+-independent Mg2+ efflux functions via the unspecific choline exchanger as choline/Mg2+ or K+/Mg2+ antiport and as Mg2+ efflux accompanied by intracellular Cl- for charge compensation, as found for example in sucrose medium. Na+/Mg2+ antiport in erythrocytes exchanges 2 extracellular Na+ for 1 intracellular Mg2+. Driving forces are the Na+ and Mg2+ gradients. By reversing these gradients, the Na+/Mg2+ antiporter can mediate Mg2+ influx. The Na+/Mg2+ antiporter can exchange 24Mg2+ for 28Mg2+ and other divalent cations for intracellular Mg2+. In the exchange mechanism, extra- and intracellular Na+ can compete with Mg2+. Na+/Mg2+ antiport is inhibited by amiloride, quinidine and imipramine. Na+/Mg2+ antiport is drastically activated by intracellular Mg2+ due to an allosteric transition. The affinity of intracellular Mg2+ to the Na+/Mg2+ antiporter is dependent on intracellular ATP due to phosphorylation. Besides this mechanism, in non Mg2+-loaded erythrocytes, the activity of Na+/Mg2+ antiport is regulated by phosphorylation-dephosphorylation and by intracellular Cl-. The drastically Mg2+-activated Na+/Mg2+ antiporter is not further stimulated by phosphorylation and intracellular Cl-. Na+-independent Mg2+ efflux via the choline exchanger is also inhibited by amiloride, quinidine and imipramine, and can also be regulated by phosphorylation-dephosphorylation. Na+/Mg2+ antiport of erythrocytes is altered in various pathologic conditions.


Assuntos
Eritrócitos/metabolismo , Magnésio/sangue , Trifosfato de Adenosina/fisiologia , Anemia Falciforme/fisiopatologia , Animais , Antiporters/fisiologia , Cloretos/farmacologia , Colina/metabolismo , Fibrose Cística/fisiopatologia , Diabetes Mellitus/fisiopatologia , Radicais Livres/metabolismo , Humanos , Hipertensão/fisiopatologia , Falência Renal Crônica/fisiopatologia , Deficiência de Magnésio/fisiopatologia , Transtornos do Humor/fisiopatologia , Fosforilação , Sódio/fisiologia , Sacarose/farmacologia
14.
Magnes Res ; 19(1): 7-11, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16846095

RESUMO

In non Mg(2+)-loaded and non malaria-infected rat erythrocytes, mefloquine (100 micromol x l (-1)) stimulated choline/Mg2+ antiport without affecting the Na+/Mg2+ antiport. The stimulation of the choline/Mg2+ antiport by mefloquine, found in this study, and by trifluoperazine and fluvoxamine, reported previously [Ebel et al. Biochim Biophys Acta 2004; 1167: 132-40], was associated with CF3 groups attached to the quinoline or benzene ring. The effect of mefloquine on choline/Mg2+ antiport in vitro was not related to the antimalarial action of mefloquine in vivo. In rat erythrocytes, the choline/Mg2+ antiport can be differentiated from the Na+/Mg2+ antiport through the use of cinchonine that inhibited the choline/Mg2+ antiport [Ebel et al. Biochim Biophys Acta 2002; 1559: 135-44], and mefloquine that stimulated the choline/Mg2+ antiport, whereby the Na+/Mg2+ antiport was not affected by either drug at proper concentrations. The Na+/Mg2+ antiport and choline/Mg2+ antiports behave as different molecular entities.


Assuntos
Antimaláricos/farmacologia , Colina/metabolismo , Eritrócitos , Transporte de Íons/efeitos dos fármacos , Magnésio/metabolismo , Mefloquina/farmacologia , Animais , Antiporters/metabolismo , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Transporte de Íons/fisiologia , Masculino , Estrutura Molecular , Ratos , Ratos Sprague-Dawley
17.
Magnes Res ; 19(4): 225-36, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17402290

RESUMO

Intracellular total Mg2+ and free Mg2+ are compartmentalized between cell organelles and within the cytosol. Different values of [Mg2+]i in the cytosol of the same cell type were measured by various investigators. A main reason for the differences is the uncertainty of the dissociation constants used for the Mg furaptra complex in the fluorescence method and for MgATP when 31P NMR was employed. The more realistic KD values of Mg furaptra and MgATP measured under in situ conditions are higher than the KDs used by most investigators. The [Mg2+]is obtained and the KDs used by various authors were presented. The role of intracellular Mg2, in metabolic functions and the action of various effectors on [Mg2+]i and [Ca2+] was reviewed. Intracellular Mg2+ may have a permissive role supporting the effector-induced mechanisms that are mediated by Ca2+ as a second messenger.


Assuntos
Magnésio/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Cálcio/metabolismo , Compartimento Celular , Citosol/metabolismo , Fura-2/análogos & derivados , Humanos , Cinética , Magnésio/análise , Espectroscopia de Ressonância Magnética , Microeletrodos , Neoplasias/metabolismo , Organelas/metabolismo , Sistemas do Segundo Mensageiro
18.
Magnes Res ; 18(3): 175-85, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16259378

RESUMO

Total Mg2+ content in plasma and erythrocytes did not significantly differ between WKY and SHR. Mg2+ efflux via Na+/Mg2+ antiport was 10% lower in non Mg(2+)-loaded erythrocytes of SHR than in WKY, and 16% lower in Mg(2+)-loaded erythrocytes of SHR. The activation of Na+/Mg2+ antiport in erythrocytes by Cl-, as tested by substitution of Cl- with SCN-, and the regulation of Na+/Mg2+ antiport by protein kinases, as tested by PMA and staurosporine, showed no differences between WKY and SHR. The reduction of Na+/Mg2+ antiport was explained by a reduction in the number of Na+/Mg2+ antiporter molecules in SHR erythrocytes. Mg2+ efflux in KCl medium by K+/Mg2+ antiport via the unspecific choline exchanger was not significantly reduced in SHR and was equally affected by PMA and staurosporine in WKY and SHR. An explanation for some controversial results, unchanged or reduced concentration of Mg2+ in serum, total Mg2+ and free Mg2+ in erythrocytes of SHR and patients with essential hypertension was proposed. The role of Na+/Mg2+ antiport and [Mg2+]i in the pathogenesis of experimental and clinical hypertension was discussed.


Assuntos
Eritrócitos/metabolismo , Hipertensão/etiologia , Magnésio/metabolismo , Sódio/metabolismo , Animais , Transporte Biológico/fisiologia , Pressão Sanguínea/fisiologia , Inibidores Enzimáticos/metabolismo , Hipertensão/metabolismo , Masculino , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Estaurosporina/metabolismo , Acetato de Tetradecanoilforbol/metabolismo
19.
Orthopade ; 34(7): 698-700, 702, 2005 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-15856167

RESUMO

A 78-year old woman with osteoporotic collapse of the Th12 and L4 vertebrae was treated by percutaneous vertebroplasty (pVp) with PMMA (polymethylmethacrylate). Postoperatively, the Th11 and L1 vertebrae collapsed so that a second vertebroplasty was performed. Postoperatively, the patient developed a severe pulmonary embolism which was treated conservatively. In this report, the complications of pulmonary embolism, perivertebral leakage of PMMA and of additional vertebral collapses after pVp are discussed.


Assuntos
Extravasamento de Materiais Terapêuticos e Diagnósticos/complicações , Laminectomia/efeitos adversos , Polimetil Metacrilato/efeitos adversos , Polimetil Metacrilato/uso terapêutico , Embolia Pulmonar/induzido quimicamente , Fraturas da Coluna Vertebral/etiologia , Vértebras Torácicas/cirurgia , Idoso , Feminino , Humanos , Fraturas da Coluna Vertebral/complicações , Vértebras Torácicas/efeitos dos fármacos , Falha de Tratamento
20.
J Neural Transm (Vienna) ; 112(7): 955-67, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15517429

RESUMO

The effects of repetitive transcranial magnetic stimulation (rTMS) on schizophrenic negative symptoms (NS) and EEG topography were investigated in this pilot study. 10 patients with predominant NS were treated with 10 Hz rTMS over the left dorsolateral prefrontal cortex for 5 days. For NS ratings, the Scale for the Assessment of Negative Symptoms (SANS) was used. Both ratings and EEG recordings were obtained pre- and post-rTMS. Electrical activity changes were computed by Low Resolution Brain Electromagnetic Tomography. SANS showed an improvement after rTMS, from 49.0 (SD: 10.7) to 44.7 (SD: 11.8) (means). EEG frequency bands were changed fronto-temporally (right) and were mainly decreases in delta- and beta- and increases in alpha1-activity, as well as decreases in beta-activity in the temporal and parieto-occipital regions (left). Although we are aware of the limitations of this study, we assume a slight improvement in NS. The EEG findings refer to a possible neurophysiologic correlate of their improvement after rTMS.


Assuntos
Encéfalo/fisiopatologia , Terapia por Estimulação Elétrica , Magnetismo/uso terapêutico , Esquizofrenia/terapia , Adulto , Idoso , Eletroencefalografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto
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