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1.
Sci Total Environ ; 912: 169127, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38070554

RESUMEN

Diet is a primary source of nutrients but also toxic metal exposure. In pregnancy, balancing essential metal exposure while reducing non-essential ones is vital for fetal and maternal health. However, the effect of metal mixtures from diets like the Mediterranean, known for health benefits, remains unclear. This study aimed to explore the association between Mediterranean diet adherence and metals exposure, both individually and as mixtures. The study involved 907 pregnant participants from the New Hampshire Birth Cohort Study. We calculated the relative Mediterranean diet score (rMED) through a validated food frequency questionnaire, which includes 8 traditional Mediterranean dietary components. Also, at ~24-28 weeks of gestation, we used ICP-MS to measure speciation of Al, Cd, Co, Cu, Fe, Hg, Mo, Ni, Sb, Se, Sn, Zn, and As in urine, as well as Pb, Hg, As, Ni, and Se in toenails. We used multiple linear regression and Weighted Quantile Sum regression to analyze the association between rMED and metal mixtures. The models were adjusted for age, pre-pregnancy BMI, smoking during pregnancy, and educational level. High adherence to the Mediterranean diet was associated with increased urinary Al (® = 0.26 (95 % confidence interval (CI) = 0.05; 0.46)), Cd (ß = 0.12 (95%CI = 0.00; 0.24)), Mo (ß = 0.10 (95%CI = 0.00; 0.20)), and AsB (ß = 0.88 (95%CI = 0.49; 1.27)) as well as toenail Hg (ß = 0.44 (95%CI = 0.22; 0.65)), Ni (ß = 0.37 (95%CI = 0.06; 0.67)), and Pb (ß = 0.22 (95%CI = 0.03; 0.40)) compared to those with low adherence. The intake of fruits and nuts, fish and seafood, legumes, cereals, meat, and olive oil were found to be related to the metal biomarkers within the rMED. In conclusion, the Mediterranean diet enhances essential metal intake but may also increase exposure to harmful ones.


Asunto(s)
Dieta Mediterránea , Mercurio , Embarazo , Femenino , Animales , Humanos , Estudios de Cohortes , Cadmio , New Hampshire , Plomo
2.
IEEE Trans Biomed Eng ; 63(9): 1812-1819, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-26625400

RESUMEN

OBJECTIVE: Image registration of whole slide histology images allows the fusion of fine-grained information-like different immunohistochemical stains-from neighboring tissue slides. Traditionally, pathologists fuse this information by looking subsequently at one slide at a time. If the slides are digitized and accurately aligned at cell level, automatic analysis can be used to ease the pathologist's work. However, the size of those images exceeds the memory capacity of regular computers. METHODS: We address the challenge to combine a global motion model that takes the physical cutting process of the tissue into account with image data that is not simultaneously globally available. Typical approaches either reduce the amount of data to be processed or partition the data into smaller chunks to be processed separately. Our novel method first registers the complete images on a low resolution with a nonlinear deformation model and later refines this result on patches by using a second nonlinear registration on each patch. Finally, the deformations computed on all patches are combined by interpolation to form one globally smooth nonlinear deformation. The NGF distance measure is used to handle multistain images. RESULTS: The method is applied to ten whole slide image pairs of human lung cancer data. The alignment of 85 corresponding structures is measured by comparing manual segmentations from neighboring slides. Their offset improves significantly, by at least 15%, compared to the low-resolution nonlinear registration. CONCLUSION/SIGNIFICANCE: The proposed method significantly improves the accuracy of multistain registration which allows us to compare different antibodies at cell level.


Asunto(s)
Interpretación de Imagen Asistida por Computador/métodos , Imagenología Tridimensional/métodos , Neoplasias Pulmonares/patología , Microscopía/métodos , Reconocimiento de Normas Patrones Automatizadas/métodos , Técnica de Sustracción , Algoritmos , Rastreo Celular/métodos , Humanos , Dinámicas no Lineales , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Procesamiento de Señales Asistido por Computador
3.
Eur J Med Res ; 16(10): 457-68, 2011 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-22024425

RESUMEN

OBJECTIVES: Current quality of life inventories used in oncology mainly measure the effects of chemo- or radiotherapy alongside functional and role scales. A new approach is to measure the autonomic state of regulation with the trait-inventory of autonomic regulation (Trait-aR). Loss of Trait-aR has been shown in different medical conditions such as breast cancer (BC) but not in colorectal cancer patients (CRC). In this paper we report the validation of a new state autonomic regulation scale (State-aR) of the last week. METHODS: Study 1 included 114 participants: (41 women/16 men with cancer and 57 age- and gender-matched healthy people) to conduct a reliability-, factor- and validity-analysis. Concurrent and convergent validity was evaluated with Trait-aR, Fatigue-Numerical-Scale, Hospital Anxiety and Depression Scale (HADS-D) and the self-regulation scale, 65 participants were retested. Study 2 completed 42 participants: 17 with BC and 25 with CRC receiving chemotherapy. The State-aR was administered prior, during and after chemotherapy for measuring responsiveness. RESULTS: The factor analysis loaded to four subscales of State-aR (rest-activity, orthostatic-circulatory, thermo-sweating and digestive regulation) with a: Cronbach-α r(α) = 0.77?0.83 and a test-retest-reliability r(rt) = 0.60?0.80. The sum- and subscales correlated with their concurrent subscales in the Trait-aR (0.48?0.74) and with the sum-scale moderately with all convergent criteria (r = 0.41?-0.44; p <0.001). During chemotherapy the State-aR-sum and rest-activity-scale decreased significantly compared to the change in the Trait-aR (p <0.05). CONCLUSIONS: These findings support that the state autonomic regulation scale has satisfactory to good reliability, good validity and acceptable responsiveness in the context of chemotherapy treatment.


Asunto(s)
Sistema Nervioso Autónomo/fisiología , Neoplasias/fisiopatología , Psicometría , Calidad de Vida , Encuestas y Cuestionarios/normas , Estudios de Casos y Controles , Análisis Factorial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/psicología , Pronóstico
4.
Eur J Cancer Care (Engl) ; 17(1): 33-41, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18181889

RESUMEN

Fatigue is a very important factor determining the quality of life in patients with malignancies. Cancer fatigue occurs with anaemia, during and after chemo- or radiotherapy and in patients with advanced tumours. The Cancer Fatigue Scale (CFS) is a three-dimensional inventory with 15 items which was originally developed in Japan. We present the results of a validation study of the German version (CFS-D) of this instrument. The CFS-D was administered to 114 participants in a matched-pair study. In total, 57 (41 women) of the participants had malignant conditions, and 57 (41 women) were healthy volunteers. The Fatigue Numerical Scale was used to test convergence. The physical and performance status of the cancer patients was assessed by the Karnofsky-Index. Criteria for testing multidimensionality were the Hospital Anxiety and Depression Scale, and the questionnaire on autonomic regulation. We generated a three-dimensional inventory of the CFS-D with the subscales physical fatigue/vitality, cognitive and affective fatigue. The reliability results for the complete scale: Cronbach's alpha: r(alpha) = 0.94, retest reliability: r(rt) = 0.82. The convergence criteria correlate between r = 0.44-0.65 (all P < 0.001). The CFS-D is highly reliable and has construct validity in relation to other measures.


Asunto(s)
Fatiga/diagnóstico , Neoplasias/complicaciones , Calidad de Vida/psicología , Actividades Cotidianas , Adulto , Anciano , Anciano de 80 o más Años , Fatiga/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/psicología , Pruebas Psicológicas , Índice de Severidad de la Enfermedad
5.
J Antimicrob Chemother ; 60(6): 1391-4, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17962215

RESUMEN

OBJECTIVES: To assess the synergistic potential of the novel diaminopyrimidine iclaprim (formerly AR-100, Ro 48-2622), a specific and selective inhibitor of microbial dihydrofolate reductase (DHFR), in combination with other antimicrobial agents with distinctly different mechanisms of action. METHODS: In chequerboard studies, iclaprim was tested in combination with 32 different antimicrobial agents against Gram-positive, Gram-negative and anaerobic bacteria including reference strains. RESULTS: Iclaprim was highly synergistic against the strains tested with the two sulphonamides selected, namely, sulfamethoxazole and sulfadiazine. With the other 28 antimicrobial agents, neither synergy nor antagonism was observed with macrolides, lincosamides, aminoglycosides, quinolones, beta-lactams, trimethoprim, tetracyclines and glycopeptides. Furthermore, iclaprim exhibited no synergy or antagonism when evaluated in combination with metronidazole or aztreonam against a panel of 19 bacterial strains, including Gram-positive, Gram-negative and selected anaerobic bacteria. CONCLUSIONS: In agreement with the mechanism of action of microbial DHFR inhibitors, iclaprim exhibited synergism with sulphonamides and exhibited neither antagonism nor synergy with all the other antibiotics tested. Notably, iclaprim exhibited indifference in combination with aztreonam and metronidazole against Gram-negatives and anaerobes, respectively.


Asunto(s)
Antibacterianos/farmacología , Antagonistas del Ácido Fólico/farmacología , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Pirimidinas/farmacología , Farmacorresistencia Bacteriana , Sinergismo Farmacológico , Humanos , Pruebas de Sensibilidad Microbiana
6.
J Antimicrob Chemother ; 60(6): 1388-90, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17951265

RESUMEN

OBJECTIVES: Iclaprim is a novel diaminopyrimidine for which a human plasma binding level of approximately 93% has been reported. The purpose of this study was to evaluate the effect of human plasma on the in vitro activity of iclaprim and to compare it with that of fusidic acid, teicoplanin and vancomycin, antibiotics with protein binding to human plasma of 97%, >90% and 55%, respectively. METHODS: MICs were determined using 40 methicillin-susceptible Staphylococcus aureus (MSSA) and 38 methicillin-resistant S. aureus (MRSA) isolates in Mueller-Hinton broth (MHB) alone or in the presence of 50% human plasma. RESULTS: MICs of iclaprim were not affected by the addition of human plasma. MIC ranges (MIC(90)) for iclaprim against MSSA and MRSA were < or =0.016-0.06 mg/L (MIC(90) 0.06 mg/L) and < or =0.016-0.5 mg/L (MIC(90) 0.06 mg/L), respectively, in MHB and < or =0.016-0.125 mg/L (MIC(90) 0.06 mg/L) and < or =0.016-0.25 mg/L (MIC(90) 0.125 mg/L), respectively, in the presence of human plasma. As expected, the antimicrobial activity of fusidic acid was greatly affected by the presence of human plasma (MIC elevations of 4- to >128-fold), whereas MICs of vancomycin remained unchanged. By contrast, despite the high protein binding, MICs of teicoplanin were only marginally affected by the presence of plasma with an MIC elevation of maximum 8-fold for two strains. CONCLUSIONS: This study demonstrates that human plasma does not affect the MIC of iclaprim in vitro.


Asunto(s)
Antibacterianos/farmacología , Plasma/metabolismo , Pirimidinas/farmacología , Staphylococcus aureus/efectos de los fármacos , Antibacterianos/metabolismo , Humanos , Meticilina/metabolismo , Meticilina/farmacología , Resistencia a la Meticilina , Pruebas de Sensibilidad Microbiana , Unión Proteica , Pirimidinas/metabolismo
7.
Eur J Med Res ; 9(6): 316-22, 2004 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-15257874

RESUMEN

Mistletoe extracts exert immunomodulatory properties in vivo and in vitro, and these effects have been related mainly to mistletoe lectin 1 (ML-1). Recently, a new chitin-binding mistletoe lectin (cbML) has been isolated and structurally characterized in these extracts. Aim of the present study was, therefore, to evaluate whether this cbML also affects immunocompetent cells and can for instance activate B-cells to produce anti-cbML-specific antibodies. Sera from patients with different tumors who were treated with the mistletoe extract ABNOBAviscum Mali (AM) 4 for at least 18 weeks were analysed before therapy and after 3, 6, 9, 12, 18, and 24 weeks. Sera were tested by ELISA against ML-1, -3, and cbML, isolated from a single mistletoe plant collected from an apple tree (Malus domestica). Eight of the 26 patients (31%) had IgG anti-cbML antibodies already before therapy, while only four had anti-ML-1 and -3 antibodies. Of the 18 anti-cbML negative patients before therapy 54% developed these antibodies during therapy, and there was a significant increase in anti-cbML antibody titers. In contrast, anti-ML-1 or -3-antibodies developed in almost 100% of the 25 patients being negative before therapy. These data indicate that cbML can induce immunological responses in patients treated with mistletoe extracts, although it seems to have lower antigenicity. Interestingly, anti-cbML antibodies can be observed in a low incidence also in individuals, not having yet received mistletoe therapy.


Asunto(s)
Adyuvantes Inmunológicos/uso terapéutico , Muérdago , Neoplasias/tratamiento farmacológico , Extractos Vegetales/uso terapéutico , Lectinas de Plantas/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos/análisis , Anticuerpos/sangre , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/inmunología , Carcinoma Basocelular/tratamiento farmacológico , Carcinoma Basocelular/inmunología , Carcinoma de Células Renales/tratamiento farmacológico , Carcinoma de Células Renales/inmunología , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/inmunología , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/inmunología , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/inmunología
8.
Artículo en Alemán | MEDLINE | ID: mdl-12808365

RESUMEN

INTRODUCTION: Objective of this study was to develop a questionnaire for endogenous regulation (eR) and to evaluate its relevance in clinical and preventive medicine. The inventory included items about sleeping and waking, orthostatic regulation, thermoregulation, and circadian well-being. METHODS: 158 age-matched women with diabetes (1/2, n = 53), breast cancer (n = 52) and healthy controls (n = 53) filled in the Havelhöhe constitutional questionnaire (HKF1.0), and a 24-h-Oxford-FD3-ECG was recorded. RESULTS: We developed a twelve-items scale for eR, which is according to test theory an objective and reliable instrument (Cronbach-alpha: r alpha = 0.71, retest reliability: rt = 0.83). The validity analysis confirmed that the breast cancer and diabetic group show a lower eR than the control group (both p < 0.001). Furthermore, high eR is correlated with a 'rare tendency to feel quite low', 'less allergies', 'less period pains', and a 'shorter duration of breast cancer'. Therefore eR can be regarded as a marker for health and well-being. High eR correlates as well with personality traits as morningness, 'needing less time for thinking through', 'being less unsure at important decisions', and 'being less confidential'. We can show first correlations between eR and the rhythmical marker 'nightly pattern predominance'. With both methods we are achieving for women until 60 years a satisfying discrimination between breast cancer and healthy individuals. CONCLUSIONS: We are achieving a first validation of our scale of endogenous regulation. Further studies for the evaluation of the conceptual, clinical, rehabilitative, and preventive medicine relevance of eR are necessary.


Asunto(s)
Neoplasias de la Mama/psicología , Diabetes Mellitus/psicología , Estado de Salud , Encuestas y Cuestionarios/normas , Adulto , Anciano , Anciano de 80 o más Años , Regulación de la Temperatura Corporal , Neoplasias de la Mama/fisiopatología , Estudios de Casos y Controles , Ritmo Circadiano , Diabetes Mellitus/fisiopatología , Femenino , Humanos , Persona de Mediana Edad , Reproducibilidad de los Resultados , Autoimagen , Sensibilidad y Especificidad
9.
Eur J Med Res ; 7(8): 359-67, 2002 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-12204844

RESUMEN

Mistletoe extracts exert immunomodulatory properties on immunocompetent cells of the innate as well as the specific immune system. These effects have been mainly ascribed to mistletoe lectin 1 (ML-1) present in most of the extracts. However, it became evident that also other components of these extracts may induce immunological reactions, and especially viscotoxins (VT) may be of relevance. Aim of the study was, therefore, to evaluate whether VT like ML-1 could activate B-cells and lead to the production of VT-specific antibodies. Sera from 26 patients with different tumours who were treated with the mistletoe extract ABNOBAviscum Mali (AM) 4 for at least 18 weeks were analysed before therapy and after 3, 6, 9, 12, and 18 weeks. Sera were tested by ELISA against the four viscotoxins A1, A2, A3, B, as well as against ML-1. Within the observation period twenty-four (92%) of the 26 patients developed antibodies to at least one of the four VT and 25 (96%) to ML-1. In most instances, anti-VT antibodies appeared after 6-9 weeks of treatment. The antibodies were predominantly of the IgG type belonging preferentially to the IgG1 and IgG3 subclass. IgE antibodies were found only to VT-B and to ML-1. There was no relation between the development of antibodies to VT and ML-1, and also cross-reactivity could be excluded with high probability. These data indicate that not only ML-1 but also VT induce immunological responses in patients treated with mistletoe extracts. Whether there is any relationship to the postulated anti-tumour effect of mistletoe extracts has, however, still to be evaluated.


Asunto(s)
Adyuvantes Inmunológicos/uso terapéutico , Muérdago , Neoplasias/tratamiento farmacológico , Preparaciones de Plantas/inmunología , Preparaciones de Plantas/uso terapéutico , Proteínas de Plantas , Toxinas Biológicas/inmunología , Toxinas Biológicas/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos/análisis , Anticuerpos/sangre , Linfocitos B/inmunología , Western Blotting , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/inmunología , Carcinoma de Células Renales/tratamiento farmacológico , Carcinoma de Células Renales/inmunología , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/inmunología , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Neoplasias Renales/tratamiento farmacológico , Neoplasias Renales/inmunología , Masculino , Persona de Mediana Edad , Neoplasias/inmunología , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/inmunología , Proteínas Inactivadoras de Ribosomas Tipo 2
10.
J Bacteriol ; 183(5): 1727-33, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11160104

RESUMEN

A dissimilatory sulfite reductase (DSR) was purified from the anaerobic, taurine-degrading bacterium Bilophila wadsworthia RZATAU to apparent homogeneity. The enzyme is involved in energy conservation by reducing sulfite, which is formed during the degradation of taurine as an electron acceptor, to sulfide. According to its UV-visible absorption spectrum with maxima at 392, 410, 583, and 630 nm, the enzyme belongs to the desulfoviridin type of DSRs. The sulfite reductase was isolated as an alpha2beta)gamma(n) (n > or = 2) multimer with a native size of 285 kDa as determined by gel filtration. We have sequenced the genes encoding the alpha and beta subunits (dsrA and dsrB, respectively), which probably constitute one operon. dsrA and dsrB encode polypeptides of 49 (alpha) and 54 kDa (beta) which show significant similarities to the homologous subunits of other DSRs. The dsrB gene product of B. wadsworthia is apparently a fusion protein of dsrB and dsrD. This indicates a possible functional role of DsrD in DSR function because of its presence as a fusion protein as an integral part of the DSR holoenzyme in B. wadsworthia. A phylogenetic analysis using the available Dsr sequences revealed that B. wadsworthia grouped with its closest 16S rDNA relative Desulfovibrio desulfuricans Essex 6.


Asunto(s)
Deltaproteobacteria/enzimología , Oxidorreductasas actuantes sobre Donantes de Grupos Sulfuro/genética , Oxidorreductasas actuantes sobre Donantes de Grupos Sulfuro/metabolismo , Taurina/metabolismo , Secuencia de Aminoácidos , Anaerobiosis , Deltaproteobacteria/genética , Deltaproteobacteria/crecimiento & desarrollo , Electroforesis en Gel de Poliacrilamida , Datos de Secuencia Molecular , Oxidorreductasas/metabolismo , Oxidorreductasas actuantes sobre Donantes de Grupos Sulfuro/aislamiento & purificación , Filogenia , Análisis de Secuencia de ADN , Sulfatos/metabolismo , Sulfitos/metabolismo
11.
Eur J Biochem ; 267(23): 6841-8, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11082195

RESUMEN

Bilophila wadsworthia RZATAU is a Gram-negative bacterium which converts the sulfonate taurine (2-aminoethanesulfonate) to ammonia, acetate and sulfide in an anaerobic respiration. Taurine:pyruvate aminotransferase (Tpa) catalyses the initial metabolic reaction yielding alanine and sulfoacetaldehyde. We purified Tpa 72-fold to apparent homogeneity with an overall yield of 89%. The purified enzyme did not require addition of pyridoxal 5'-phosphate, but highly active enzyme was only obtained by addition of pyridoxal 5'-phosphate to all buffers during purification. SDS/PAGE revealed a single protein band with a molecular mass of 51 kDa. The apparent molecular mass of the native enzyme was 197 kDa as determined by gel filtration, which indicates a homotetrameric structure. The kinetic constants for taurine were: Km = 7.1 mM, Vmax = 1.20 nmol.s-1, and for pyruvate: Km = 0.82 mM, Vmax = 0.17 nmol.s-1. The purified enzyme was able to transaminate hypotaurine (2-aminosulfinate), taurine, beta-alanine and with low activity cysteine and 3-aminopropanesulfonate. In addition to pyruvate, 2-ketobutyrate and oxaloacetate were utilized as amino group acceptors. We have sequenced the encoding gene (tpa). It encoded a 50-kDa peptide, which revealed 33% identity to diaminopelargonate aminotransferase from Bacillus subtilis.


Asunto(s)
Deltaproteobacteria/enzimología , Taurina/análogos & derivados , Transaminasas/química , Transaminasas/genética , Butiratos/metabolismo , Cromatografía en Gel , Cromatografía Líquida de Alta Presión , Cisteína/metabolismo , Electroforesis en Gel de Poliacrilamida , Cinética , Modelos Químicos , Datos de Secuencia Molecular , Peso Molecular , Sistemas de Lectura Abierta , Ácido Oxaloacético/metabolismo , Fosfato de Piridoxal/farmacología , Taurina/metabolismo , Factores de Tiempo , Rayos Ultravioleta , beta-Alanina/metabolismo
12.
Arch Microbiol ; 174(3): 162-7, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11041346

RESUMEN

Alanine dehydrogenase [L-alanine:NAD+ oxidoreductase (deaminating), EC 1.4.1.4.] catalyses the reversible oxidative deamination of L-alanine to pyruvate and, in the anaerobic bacterium Bilophila wadsworthia RZATAU, it is involved in the degradation of taurine (2-aminoethanesulfonate). The enzyme regenerates the amino-group acceptor pyruvate, which is consumed during the transamination of taurine and liberates ammonia, which is one of the degradation end products. Alanine dehydrogenase seems to be induced during growth with taurine. The enzyme was purified about 24-fold to apparent homogeneity in a three-step purification. SDS-PAGE revealed a single protein band with a molecular mass of 42 kDa. The apparent molecular mass of the native enzyme was 273 kDa, as determined by gel filtration chromatography, suggesting a homo-hexameric structure. The N-terminal amino acid sequence was determined. The pH optimum was pH 9.0 for reductive amination of pyruvate and pH 9.0-11.5 for oxidative deamination of alanine. The apparent Km values for alanine, NAD+, pyruvate, ammonia and NADH were 1.6, 0.15, 1.1, 31 and 0.04 mM, respectively. The alanine dehydrogenase gene was sequenced. The deduced amino acid sequence corresponded to a size of 39.9 kDa and was very similar to that of the alanine dehydrogenase from Bacillus subtilis.


Asunto(s)
Aminoácido Oxidorreductasas , Bacterias Anaerobias/enzimología , Deltaproteobacteria/enzimología , Taurina/metabolismo , Alanina-Deshidrogenasa , Aminoácido Oxidorreductasas/química , Aminoácido Oxidorreductasas/genética , Aminoácido Oxidorreductasas/aislamiento & purificación , Aminoácido Oxidorreductasas/metabolismo , Secuencia de Aminoácidos , Bacterias Anaerobias/genética , Bacterias Anaerobias/crecimiento & desarrollo , Catálisis , ADN Bacteriano/genética , Deltaproteobacteria/genética , Deltaproteobacteria/crecimiento & desarrollo , Cinética , Datos de Secuencia Molecular , Análisis de Secuencia de ADN
13.
Eur J Med Res ; 3(4): 194-202, 1998 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-9533928

RESUMEN

There is evidence from recent data that mistletoe extracts exert immunostimulatory properties which could explain their therapeutic effects observed in some tumor patients. Aim of our study was, therefore, to investigate the effect of a subcutaneous 16-weeks therapy with a mistletoe extract (ABNOBAviscum Mali, AM) on the cellular and humoral immune responses in eight breast cancer patients. Mistletoe therapy induced a strong initial proliferation of peripheral blood mononuclear cells (PBMC) in all individuals, which, however, decreased in six patients during the observation period, indicating that not only activating but also inhibitory mechanisms have been induced. In all supernatants of AM-stimulated cell cultures TNF-alpha or IL-6 were found, indicating the activation of cells of the monocyte-/macrophage lineage by mistletoe extracts. Further analyses revealed, that AM induced in vitro also the release of low amounts of IFN-gamma and IL-4 with individual variations. At the end of the therapy, a shift to Th1- related cytokines could be observed in the in vitro cell culture system. All patients produced anti-mistletoe lectin 1 antibodies of the IgG-type during therapy and in four of them additionally antibodies of the IgE-type were found. It, therefore, seems that AM can influence the Th1/Th2 balance and, in case of a Th1 shift, this may favourably influence the tumor growth.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/inmunología , Sistema Inmunológico/efectos de los fármacos , Muérdago/uso terapéutico , Fitoterapia , Plantas Medicinales , Adyuvantes Inmunológicos/uso terapéutico , Adulto , Anciano , División Celular/efectos de los fármacos , Femenino , Humanos , Inmunoglobulina E/sangre , Inmunoglobulina G/sangre , Interleucina-4/sangre , Interleucina-6/sangre , Leucocitos Mononucleares/citología , Leucocitos Mononucleares/inmunología , Persona de Mediana Edad , Muérdago/inmunología , Extractos Vegetales/uso terapéutico , Factor de Necrosis Tumoral alfa/metabolismo
14.
FEMS Microbiol Rev ; 22(5): 399-419, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9990724

RESUMEN

Organosulfonates are widespread compounds, be they natural products of low or high molecular weight, or xenobiotics. Many commonly found compounds are subject to desulfonation, even if it is not certain whether all the corresponding enzymes are widely expressed in nature. Sulfonates require transport systems to cross the cell membrane, but few physiological data and no biochemical data on this topic are available, though the sequences of some of the appropriate genes are known. Desulfonative enzymes in aerobic bacteria are generally regulated by induction, if the sulfonate is serving as a carbon and energy source, or by a global network for sulfur scavenging (sulfate-starvation-induced (SSI) stimulon) if the sulfonate is serving as a source of sulfur. It is unclear whether an SSI regulation is found in anaerobes. The anaerobic bacteria examined can express the degradative enzymes constitutively, if the sulfonate is being utilized as a carbon source, but enzyme induction has also been observed. At least three general mechanisms of desulfonation are recognisable or postulated in the aerobic catabolism of sulfonates: (1) activate the carbon neighboring the C-SO3- bond and release of sulfite assisted by a thiamine pyrophosphate cofactor; (2) destabilize the C-SO3- bond by addition of an oxygen atom to the same carbon, usually directly by oxygenation, and loss of the good leaving group, sulfite; (3) an unidentified, formally reductive reaction. Under SSIS control, different variants of mechanism (2) can be seen. Catabolism of sulfonates by anaerobes was discovered recently, and the degradation of taurine involves mechanism (1). When anaerobes assimilate sulfonate sulfur, there is one common, unknown mechanism to desulfonate the inert aromatic compounds and another to desulfonate inert aliphatic compounds; taurine seems to be desulfonated by mechanism (1).


Asunto(s)
Alcanosulfonatos/metabolismo , Bacterias Anaerobias/metabolismo , Biodegradación Ambiental , Fermentación , Oxidación-Reducción
15.
Arch Microbiol ; 168(4): 297-301, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9297467

RESUMEN

Thiosulfate (S2O32-) is a natural product that is widely utilized in natural ecosystems as an electron sink or as an electron donor. However, the major biological source(s) of this thiosulfate is unknown. We present the first report that taurine (2-aminoethanesulfonate), the major mammalian solute, is subject to fermentation. This bacterial fermentation was found to be catalyzed by a new isolate, strain GKNTAU, a strictly anaerobic, gram-positive, motile rod that formed subterminal spores. Thiosulfate was a quantitative fermentation product. The other fermentation products were ammonia and acetate, and all could be formed by cell-free extracts.


Asunto(s)
Bacilos Grampositivos Formadores de Endosporas/metabolismo , Taurina/metabolismo , Tiosulfatos/metabolismo , Acetatos/metabolismo , Amoníaco/metabolismo , Anaerobiosis , Biodegradación Ambiental , Medios de Cultivo Condicionados/metabolismo , Fermentación , Bacilos Grampositivos Formadores de Endosporas/crecimiento & desarrollo , Bacilos Grampositivos Formadores de Endosporas/aislamiento & purificación
16.
Appl Environ Microbiol ; 63(5): 2016-21, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9143131

RESUMEN

Organosulfonates are important natural and man-made compounds, but until recently (T. J. Lie, T. Pitta, E. R. Leadbetter, W. Godchaux III, and J. R. Leadbetter. Arch. Microbiol. 166:204-210, 1996), they were not believed to be dissimilated under anoxic conditions. We also chose to test whether alkane- and arenesulfonates could serve as electron sinks in respiratory metabolism. We generated 60 anoxic enrichment cultures in mineral salts medium which included several potential electron donors and a single organic sulfonate as an electron sink, and we used material from anaerobic digestors in communal sewage works as inocula. None of the four aromatic sulfonates, the three unsubstituted alkanesulfonates, or the N-sulfonate tested gave positive enrichment cultures requiring both the electron donor and electron sink for growth. Nine cultures utilizing the natural products taurine, cysteate, or isethionate were considered positive for growth, and all formed sulfide. Two clearly different pure cultures were examined. Putative Desulfovibrio sp. strain RZACYSA, with lactate as the electron donor, utilized sulfate, aminomethanesulfonate, taurine, isethionate, and cysteate, converting the latter to ammonia, acetate, and sulfide. Strain RZATAU was identified by 16S rDNA analysis as Bilophila wadsworthia. In the presence of, e.g., formate as the electron donor, it utilized, e.g., cysteate and isethionate and converted taurine quantitatively to cell material and products identified as ammonia, acetate, and sulfide. Sulfite and thiosulfate, but not sulfate, were utilized as electron sinks, as was nitrate, when lactate was provided as the electron donor and carbon source. A growth requirement for 1,4-naphthoquinone indicates a menaquinone electron carrier, and the presence of cytochrome c supports the presence of an electron transport chain. Pyruvate-dependent disappearance of taurine from cell extracts, as well as formation of alanine and release of ammonia and acetate, was detected. We suspected that sulfite is an intermediate, and we detected desulfoviridin (sulfite reductase). We thus believe that sulfonate reduction is one aspect of a respiratory system transferring electrons from, e.g., formate to sulfite reductase via an electron transport system which presumably generates a proton gradient across the cell membrane.


Asunto(s)
Bacterias Anaerobias Gramnegativas/metabolismo , Taurina/metabolismo , Acetatos/metabolismo , Alanina/biosíntesis , Amoníaco/metabolismo , Anaerobiosis , Reactores Biológicos , Ácido Cisteico/metabolismo , ADN Bacteriano/análisis , Formiatos/metabolismo , Bacterias Anaerobias Gramnegativas/clasificación , Bacterias Anaerobias Gramnegativas/genética , Ácido Isetiónico/metabolismo , Ácido Láctico/metabolismo , Datos de Secuencia Molecular , Oxidación-Reducción , Filogenia , ARN Ribosómico 16S/genética , Aguas del Alcantarillado/microbiología , Sulfatos/metabolismo , Sulfuros/metabolismo , Sulfitos/metabolismo , Tiosulfatos/metabolismo
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