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1.
Rev Sci Instrum ; 92(6): 063903, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34243590

RESUMO

We present a new autoclave that enables in situ characterization of hydrothermal fluids at high pressures and high temperatures at synchrotron x-ray radiation sources. The autoclave has been specifically designed to enable x-ray absorption spectroscopy in fluids with applications to mineral solubility and element speciation analysis in hydrothermal fluids in complex compositions. However, other applications, such as Raman spectroscopy, in high-pressure fluids are also possible with the autoclave. First experiments were run at pressures between 100 and 600 bars and at temperatures between 25 °C and 550 °C, and preliminary results on scheelite dissolution in fluids of different compositions show that the autoclave is well suited to study the behavior of ore-forming metals at P-T conditions relevant to the Earth's crust.

2.
Dtsch Med Wochenschr ; 137(44): 2256-9, 2012 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-23093396

RESUMO

HISTORY: A 69-year-old female patient who had been physically and mentally healthy was admitted to our emergency department because of acute onset of amnesia. INVESTIGATIONS: Inconspicuous diagnostic findings led to the diagnosis of transient global amnesia (TGA). Furthermore bradycardia and elevated troponins were detected. Because of these findings a cardiologic workup was performed resulting in the diagnosis of Tako-Tsubo cardiomyopathy. TREATMENT AND COURSE: The patient recovered completely from TGA as well as from the slight reduction of the left-ventricular ejection fraction as part of the Tako-Tsubo cardiomyopathy. CONCLUSION: There are similarities of the two diseases Tako-Tsubo cardiomyopathy and TGA concerning triggers as well as reversibility. Patients presenting with symptoms suggestive for TGA should be considered to undergo additional cardiologic evaluation.


Assuntos
Amnésia Global Transitória/diagnóstico , Cardiomiopatia de Takotsubo/diagnóstico , Idoso , Bloqueio Atrioventricular/diagnóstico , Bradicardia/etiologia , Comorbidade , Comportamento Cooperativo , Diagnóstico Diferencial , Eletrocardiografia , Serviço Hospitalar de Emergência , Feminino , Humanos , Comunicação Interdisciplinar , Processamento de Sinais Assistido por Computador , Troponina/sangue , Disfunção Ventricular Esquerda/etiologia
3.
Appl Microbiol Biotechnol ; 80(1): 29-36, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18542947

RESUMO

Long-chain alkyl benzoates, e.g., lauryl 4-hydroxybenzoate, palmityl 4-hydroxybenzoate, and oleyl 4-hydroxy-3-methoxybenzoate, are formed in high to moderate conversion by lipase-catalyzed transesterification of the corresponding short-chain alkyl benzoates (0.3 to 1 mmol) with fatty alcohols in an equimolar ratio. The substrates are reacted in vacuo in the absence of solvents and drying agents in the reaction mixture. Immobilized lipase B from Candida antarctica (Novozym 435) demonstrates higher activity for the transesterification of various methyl (hydroxy)benzoates with long-chain alcohols than for the corresponding esterification reactions. For example, transesterification activity is around 25-fold higher than esterification activity for the preparation of oleyl 4-hydroxybenzoate. The relative transesterification activities of methoxy- and hydroxy-substituted methyl benzoates found for Novozym 435 are as follows: 2-methoxybenzoate approximately 3-methoxybenzoate > 4-methoxybenzoate > 3-hydroxybenzoate approximately 2-hydroxybenzoate > 4-hydroxybenzoate approximately 4-hydroxy-3-methoxybenzoate approximately 3-hydroxy-4-methoxybenzoate > > 3,4-dihydroxybenzoate. With respect to the position of the substituents at the phenyl moiety of methyl benzoates, transesterification activity of Novozym 435 increases in the order ortho approximately meta > para. Compounds with inverse chemical structure, e.g., (methoxy)benzyl alkanoates, are formed in much higher rates both by esterification and transesterification than the analogous alkyl benzoates. Purification by deacidification, crystallization, or vacuum distillation yielded 74% to 89% of the reaction products.


Assuntos
Benzoatos/metabolismo , Enzimas Imobilizadas/metabolismo , Ésteres/metabolismo , Microbiologia Industrial , Lipase/metabolismo , Benzoatos/química , Catálise , Enzimas Imobilizadas/genética , Esterificação , Ésteres/química , Proteínas Fúngicas , Lipase/genética
4.
Z Kardiol ; 93(10): 813-7, 2004 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-15492897

RESUMO

Cardiac resynchronization therapy by multisite biventricular pacing presents an additive therapeutic option in the treatment of severe heart failure. Biventricular pacemaker implantation is challenging in patients with persistent left superior vena cava. We describe in this case report the implantation of a biventricular pacemaker using a left-sided approach in a patient with persistent left superior vena cava.


Assuntos
Eletrocardiografia , Insuficiência Cardíaca/terapia , Marca-Passo Artificial , Disfunção Ventricular Esquerda/terapia , Idoso , Angiografia Coronária , Ecocardiografia , Ecocardiografia Doppler , Eletrodos Implantados , Feminino , Insuficiência Cardíaca/diagnóstico por imagem , Humanos , Disfunção Ventricular Esquerda/diagnóstico por imagem
5.
J Agric Food Chem ; 49(11): 5210-6, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11714305

RESUMO

Sitostanol has been converted in high to near-quantitative extent to the corresponding long-chain acyl esters via esterification with oleic acid or transesterification with methyl oleate or trioleoylglycerol using immobilized lipases from Rhizomucor miehei (Lipozyme IM) and Candida antarctica (lipase B, Novozym 435) as biocatalysts in vacuo (20-40 mbar) at 80 degrees C, whereas the conversion was markedly lower at 60 and 40 degrees C. Corresponding conversions observed with papaya (Carica papaya) latex lipase were generally lower. High conversion rates observed in transesterification of sitostanol with methyl oleate at 80 degrees C using Lipozyme IM were retained even after 10 repeated uses of the biocatalyst. Saturated sterols such as sitostanol and 5alpha-cholestan-3beta-ol were the preferred substrates as compared to Delta(5)-unsaturated cholesterol in transesterification reactions with methyl oleate using Lipozyme IM. Transesterification of cholesterol with dimethyl 1,8-octanedioate using Lipozyme IM in vacuo yielded methylcholesteryl 1,8-octanedioate (75%) and dicholesteryl 1,8-octanedioate (5%). However, transesterification of cholesterol with diethyl carbonate and that of oleyl alcohol with ethylcholesteryl carbonate, both catalyzed by Lipozyme IM, gave ethylcholesteryl carbonate and oleylcholesteryl carbonate, respectively, in low yield (20%). Moreover, cholesterol was transesterified with ethyl dihydrocinnamate using Lipozyme IM to give cholesteryl dihydrocinnamate in moderate yield (56%), whereas the corresponding reaction of lanosterol gave lanosteryl oleate in low yield (14%).


Assuntos
Candida/enzimologia , Ácidos Graxos/química , Lipase/química , Magnoliopsida/química , Rhizomucor/enzimologia , Cromatografia em Camada Fina , Esterificação , Ésteres , Cinética , Estrutura Molecular , Solventes
6.
J Agric Food Chem ; 49(2): 647-51, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11262006

RESUMO

Fatty acids obtained from seed oils of crambe (Crambe abyssinica) and camelina (Camelina sativa) via alkaline saponification or steam splitting were esterified using lipases as biocatalysts with oleyl alcohol and the alcohols derived from crambe and camelina oils via hydrogenolysis of their methyl esters. Long-chain wax esters were thus obtained in high yields when Novozym 435 (immobilized lipase B from Candida antarctica) and papaya (Carica papaya) latex lipase were used as biocatalysts and vacuum was applied to remove the water formed. The highest conversions to wax esters were obtained with Novozym 435 (> or =95%) after 4-6 h of reaction, whereas with papaya latex lipase such a high degree of conversion was attained after 24 h. Products obtained from stoichiometric amounts of substrates were almost exclusively (>95%) composed of wax esters having compositions approaching that of jojoba (Simmondsia chinensis) oil, especially when crambe fatty acids in combination with camelina alcohols or camelina fatty acids in combination with crambe alcohols were used as substrates.


Assuntos
Brassicaceae/química , Ésteres/metabolismo , Ácidos Graxos/metabolismo , Álcoois Graxos/metabolismo , Lipase/metabolismo , Óleos de Plantas/química , Rosales/química , Ceras/metabolismo , Enzimas Imobilizadas/metabolismo , Ácidos Graxos/isolamento & purificação , Álcoois Graxos/isolamento & purificação , Frutas/enzimologia , Proteínas Fúngicas , Cinética , Sementes
7.
J Agric Food Chem ; 49(1): 67-71, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11170561

RESUMO

Sterols (sitosterol, cholesterol, stigmasterol, ergosterol, and 7-dehydrocholesterol) and sitostanol have been converted in high to near-quantitative yields to the corresponding long-chain acyl esters via esterification with fatty acids or transesterification with methyl esters of fatty acids or triacylglycerols using lipase from Candida rugosa as biocatalyst in vacuo (20-40 mbar) at 40 degrees C. Neither organic solvent nor water is added in these reactions. Under similar conditions, cholesterol has been converted to cholesteryl butyrate and steroids (5alpha-pregnan-3beta-ol-20-one or 5-pregnen-3beta-ol-20-one) have been converted to their propionic acid esters, both in moderate to high yields, via transesterification with tributyrin and tripropionin, respectively. Reaction parameters studied in esterification include the temperature and the molar ratio of the substrates as well as the amount and reuse properties of the C. rugosa lipase. Lipases from porcine pancreas, Rhizopus arrhizus, and Chromobacterium viscosum are quite ineffective as biocatalysts for the esterification of cholesterol with oleic acid under the above conditions.


Assuntos
Candida/enzimologia , Ácidos Graxos/metabolismo , Lipase/metabolismo , Esteróis/metabolismo , Catálise , Colesterol/metabolismo , Desidrocolesteróis/metabolismo , Ergosterol/metabolismo , Esterificação , Cinética , Sitosteroides/metabolismo , Estigmasterol/metabolismo , Especificidade por Substrato , Triglicerídeos/metabolismo , Vácuo
8.
Rehabilitation (Stuttg) ; 37(3): 128-33, 1998 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-9789314

RESUMO

A follow-up of patients with hip fractures discharged from a geriatric rehabilitation unit was conducted by means of a questionnaire sent to the former patients, in case of non-compliance calling to ask for participation in the study and completion of the questionnaire. 234 patients were examined, 8 of whom died during rehabilitation. From 91.8% (n = 206) discharged after rehabilitation information about their fate was obtained, from 98.7% (n = 223) if they were still alive. On discharge, mean age was 81 (+/- 9) years, time of follow up was 2.7 years after discharge. 34.5% had died, 36% of them within the first six months. Of those surviving, 93% still lived in the living conditions they had been discharged to. Comparing the activities of daily living of the survivors as assessed with a modified Barthel index (max. 110 points), at discharge by the occupational therapists, at follow up by the patients themselves, only a slight decrease was seen (95.5 +/- 19.2 points at discharge; 88.5 +/- 24.0 points at follow up; p < 0.01).


Assuntos
Fraturas do Quadril/cirurgia , Complicações Pós-Operatórias/reabilitação , Atividades Cotidianas/classificação , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Complicações Pós-Operatórias/mortalidade , Análise de Sobrevida , Resultado do Tratamento
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