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1.
J Nutr Biochem ; 25(12): 1254-62, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25277647

RESUMEN

The n-3 polyunsaturated fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have been shown to enhance the effect of chemotherapeutic drugs in clinical studies in cancer patients and to induce apoptotic tumor cell death in vitro. Until now, EPA and DHA have never been investigated in multiple myeloma (MM). Human myeloma cells (L363, OPM-1, OPM-2 and U266) and normal peripheral blood mononuclear cells were exposed to EPA and DHA, and effects on mitochondrial function and apoptosis, caspase-3 activation, gene expression and drug toxicity were measured. Exposure to EPA and DHA induced apoptosis and increased sensitivity to bortezomib in MM cells. Importantly, they did not affect viability of normal human peripheral mononuclear cells. Messenger RNA expression arrays showed that EPA and DHA modulated genes involved in multiple signaling pathways including nuclear factor (NF) κB, Notch, Hedgehog, oxidative stress and Wnt. EPA and DHA inhibited NFκB activity and induced apoptosis through mitochondrial perturbation and caspase-3 activation. Our study suggests that EPA and DHA induce selective cytotoxic effects in MM and increase sensitivity to bortezomib and calls for further exploration into a potential application of these n-3 polyunsaturated fatty acids in the therapy of MM.


Asunto(s)
Apoptosis/efectos de los fármacos , Ácido Araquidónico/farmacología , Ácidos Docosahexaenoicos/farmacología , Ácido Eicosapentaenoico/farmacología , Leucocitos Mononucleares/efectos de los fármacos , Mieloma Múltiple/patología , Antineoplásicos/farmacología , Ácidos Borónicos/farmacología , Bortezomib , Caspasa 3/genética , Caspasa 3/metabolismo , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Regulación de la Expresión Génica , Humanos , Leucocitos Mononucleares/metabolismo , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Mieloma Múltiple/metabolismo , FN-kappa B/genética , FN-kappa B/metabolismo , Pirazinas/farmacología
2.
Clin Nutr ; 32(3): 338-45, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23123043

RESUMEN

BACKGROUND & AIMS: In cancer patients, metabolic alterations, reduced immune competence and anti-cancer treatment can increase the risk of infections. A rapid-acting nutritional intervention might reduce this risk and support overall treatment. The present study investigated whether one week of intervention with a specific medical food led to fatty acid incorporation and functional immunological changes. METHODS: In a randomized, double-blind study, 38 cancer patients receiving radiotherapy consumed daily for one week 400 ml of specific medical food, which is high in protein and leucine, and enriched with fish oil and specific oligosaccharides (Active group), or iso-caloric/iso-nitrogenous product (Control group). Blood samples were taken at day 0 (baseline) and day 7. RESULTS: After one week of intervention, the incorporation of EPA and DHA in white blood cells was significantly higher in the Active group (2.6% and 2.6% of total fatty acids) compared to the Control group (1.0% and 2.2% of total fatty acids) (p < 0.001 and p < 0.05). Serum PGE2 levels decreased in the Active group and increased in the Control group (p < 0.01). No differences were observed on cytokine production in LPS-stimulated whole blood cultures. CONCLUSIONS: In cancer patients receiving radiotherapy, nutritional intervention with a specific medical food rapidly increased the percentage EPA and DHA in white blood cell phospholipids and reduced serum levels of the inflammatory mediator PGE2 within one week. CLINICAL REGISTRATION NUMBER: NTR2121.


Asunto(s)
Dinoprostona/sangre , Ácidos Docosahexaenoicos/farmacocinética , Ácido Eicosapentaenoico/farmacocinética , Neoplasias/radioterapia , Anciano , Biomarcadores/sangre , Método Doble Ciego , Femenino , Aceites de Pescado/administración & dosificación , Alimentos Fortificados/análisis , Humanos , Interferón gamma/sangre , Interleucina-10/sangre , Interleucina-1beta/sangre , Interleucina-8/sangre , Leucina/administración & dosificación , Leucocitos/química , Masculino , Persona de Mediana Edad , Oligosacáridos/administración & dosificación , Fosfolípidos/sangre , Factor de Necrosis Tumoral alfa/sangre
3.
Br J Cancer ; 100(5): 713-22, 2009 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-19259092

RESUMEN

Cancer cachexia is characterised by metabolic alterations leading to loss of adipose tissue and lean body mass and directly compromises physical performance and the quality of life of cancer patients. In a murine cancer cachectic model, the effects of dietary supplementation with a specific combination of high protein, leucine and fish oil on weight loss, muscle function and physical activity were investigated. Male CD2F1 mice, 6-7 weeks old, were divided into body weight-matched groups: (1) control, (2) tumour-bearing, and (3) tumour-bearing receiving experimental diets. Tumours were induced by s.c. inoculation with murine colon adenocarcinoma (C26) cells. Food intake, body mass, tumour size and 24 h-activity were monitored. Then, 20 days after tumour/vehicle inoculation, the animals were killed and muscle function was tested ex vivo. Tumour-bearing mice showed reduced carcass, muscle and fat mass compared with controls. EDL muscle performance and total daily activity were impaired in the tumour-bearing mice. Addition of single nutrients resulted in no or modest effects. However, supplementation of the diet with the all-in combination of high protein, leucine and fish oil significantly reduced loss of carcass, muscle and fat mass (loss in mass 45, 52 and 65% of TB-con, respectively (P<0.02)) and improved muscle performance (loss of max force reduced to 55-64% of TB-con (P<0.05)). Moreover, total daily activity normalised after intervention with the specific nutritional combination (50% of the reduction in activity of TB-con (P<0.05)). In conclusion, a nutritional combination of high protein, leucine and fish oil reduced cachectic symptoms and improved functional performance in cancer cachectic mice. Comparison of the nutritional combination with its individual modules revealed additive effects of the single components provided.


Asunto(s)
Adenocarcinoma/dietoterapia , Caquexia/dietoterapia , Neoplasias del Colon/dietoterapia , Aceites de Pescado/administración & dosificación , Leucina/administración & dosificación , Actividad Motora/efectos de los fármacos , Músculo Esquelético/efectos de los fármacos , Proteínas/administración & dosificación , Adenocarcinoma/complicaciones , Adenocarcinoma/fisiopatología , Animales , Peso Corporal/efectos de los fármacos , Caquexia/etiología , Caquexia/fisiopatología , Neoplasias del Colon/complicaciones , Neoplasias del Colon/fisiopatología , Suplementos Dietéticos , Combinación de Medicamentos , Aceites de Pescado/farmacología , Alimentos Formulados , Leucina/farmacología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos DBA , Músculo Esquelético/fisiología , Proteínas/farmacología
4.
Phytomedicine ; 15(5): 313-20, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-17949960

RESUMEN

Clinical studies have demonstrated that SKI306X, a purified preparation of three medicinal plants, relieves joint pain and improves functionality in osteoarthritis patients. To study the biological action of SKI306X, bovine cartilage explants and human peripheral blood mononuclear cells (PBMC) were stimulated with IL-1 beta and lipopolysaccharide (LPS) respectively, in the presence or absence of SKI306X and its individual composites. All tested compounds inhibited dose-dependently IL-1 beta-induced proteoglycan release and nitric oxide production by cartilage, indicating cartilage protective activity. SKI306X and two of its compounds inhibited PGE(2), TNF-alpha and IL-1 beta production by LPS-stimulated PBMC, indicating anti-inflammatory activity. These results demonstrate that the biological effect of SKI306X is at least bipartite: (1) cartilage protective and (2) anti-inflammatory. The observed anti-inflammatory effects may provide an explanation for the outcome of the clinical studies. Long-term clinical trails are necessary to elucidate whether the in vitro cartilage protective activity results in disease-modifying effects.


Asunto(s)
Cartílago/efectos de los fármacos , Cartílago/metabolismo , Medicamentos Herbarios Chinos/farmacología , Animales , Antiinflamatorios/farmacología , Bovinos , Clematis/química , Dinoprostona/metabolismo , Relación Dosis-Respuesta a Droga , Medicamentos Herbarios Chinos/química , Glicosaminoglicanos/metabolismo , Humanos , Inflamación/tratamiento farmacológico , Interleucina-1beta/metabolismo , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/metabolismo , Lipopolisacáridos/farmacología , Óxido Nítrico/metabolismo , Prunella/química , Trichosanthes/química , Factor de Necrosis Tumoral alfa/metabolismo
5.
Calcif Tissue Int ; 75(3): 183-8, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15386160

RESUMEN

The purpose of this study was to (1) quantify the healing process of the human osteoporotic proximal humerus fracture (PHF) expressed in terms of callus formation over the fracture region using BMD scanning, and (2) quantify the impact of medical intervention with vitamin D3 and calcium on the healing process of the human osteoporotic fracture. The conservatively treated PHF was chosen in order to follow the genuine fracture healing without influence of osteosynthetic materials or casts. Thirty women (mean age = 78 years; range = 58-88) with a PHF, osteoporosis or osteopenia (based on a hip scan, WHO criteria), and not taking any drugs related to bone formation, including calcium or vitamin D supplementation, were randomly assigned to either oral 800 IU vitamin D3 plus 1 g calcium or placebo, in a double-blind prospective study. We measured biochemical, radiographic, and bone mineral density effect parameters to evaluate the impact on the healing process. Scanning procedures of the fractured shoulder included use of a fixation device to obtain the highest possible precision. Double scans of the fractured shoulder revealed a coefficient of variation (CV) on BMD measurements that improved from 2.8% immediately after fracture occurrence to 1.7% at 12 weeks (P = 0.003) approaching the 1.2% levels observed over the healthy shoulder. BMD was similar in the two groups at baseline (active 0.534 g/cm2 vs. placebo 0.518 g/cm2), and both increased over the 12-week observation period, with peak levels in week 6. By week 6 BMD levels were higher in the active group (0.623 g/cm2) compared with the placebo group (0.570 g/cm2, P = 0.006). Thirty seven percent of the patients presented with vitamin D levels below 30 nmol/l, indicative of mild vitamin D insufficiency. In conclusion, we have demonstrated that it is possible to quantify callus formation of the PHF with sufficiently high precision to demonstrate the positive influence of vitamin D3 and calcium over the first 6 weeks after fracture. Whether this results in more stable fractures, extends to other fracture types, or applies to other osteogenic bone agents such as bisphosphonates remains to be examined.


Asunto(s)
Densidad Ósea/efectos de los fármacos , Calcio de la Dieta/uso terapéutico , Colecalciferol/uso terapéutico , Curación de Fractura/efectos de los fármacos , Fracturas del Húmero/tratamiento farmacológico , Absorciometría de Fotón , Anciano , Anciano de 80 o más Años , Enfermedades Óseas Metabólicas/tratamiento farmacológico , Calcio de la Dieta/sangre , Suplementos Dietéticos , Femenino , Humanos , Húmero/efectos de los fármacos , Persona de Mediana Edad , Osteoporosis/tratamiento farmacológico , Estudios Prospectivos
6.
J Intern Med ; 248(3): 223-9, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10971789

RESUMEN

OBJECTIVES: To determine the homocysteine-lowering effect of different treatment regimens on both fasting and postmethionine-load plasma total homocysteine (tHcy) concentrations. DESIGN: Descriptive study of consecutive hyperhomocysteinaemic subjects per treatment regimen. Homocysteine was measured in the fasting state and 6 h after methionine loading, both before and after 8 weeks of vitamin therapy. Hyperhomocysteinaemia was defined as a fasting tHcy and/or increase in tHcy (postmethionine-load minus fasting tHcy concentration) exceeding the 95th percentile of local controls. SETTING: Outpatient clinic of internal medicine of a large non-academic teaching hospital. SUBJECTS: One hundred and seventeen hyperhomocysteinaemic subjects (vascular patients and first-degree relatives). INTERVENTIONS: There were four regimens: pyridoxine, 200 mg; folic acid, 5 mg; combination of folic acid 0.5 mg and pyridoxine 100 mg; and folic acid, 0.5 mg daily. RESULTS: All regimens, except pyridoxine 200 mg, significantly reduced fasting tHcy without differences in the percentage reduction (32-38%). All regimens produced a significant reduction in the increase in tHcy and postmethionine-load tHcy. The reduction in postmethionine-load tHcy was smaller for pyridoxine 200 mg than for combination therapy. No differences were found in the percentage reduction (for both increase in tHcy and postmethionine-load tHcy) between folic acid 5 mg and folic acid 0.5 mg. CONCLUSIONS: Monotherapy folic acid (0.5 mg daily) is the lowest effective therapy for reducing both fasting and postmethionine-load tHcy concentrations, with the same results as high-dose folic acid (5 mg daily). Pyridoxine has no additional value.


Asunto(s)
Ácido Fólico/administración & dosificación , Hiperhomocisteinemia/tratamiento farmacológico , Piridoxina/administración & dosificación , Adulto , Análisis de Varianza , Distribución de Chi-Cuadrado , Cromatografía Líquida de Alta Presión , Quimioterapia Combinada , Femenino , Homocisteína/sangre , Humanos , Hiperhomocisteinemia/sangre , Masculino , Persona de Mediana Edad , Factores de Riesgo
7.
Sb Lek ; 100(3): 191-204, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-11221466

RESUMEN

Spontaneous and provoked changes of vigilance and consciousness are determined by TCS (thalamocortical system) activity. This is relatively easy to monitor using EEG, which is a complex curve but open to analysis, e.g., by means of FFT (fast Fourier transformation). Twenty six persons (six normal controls, twelve epileptics, eight dements) had EEG recorded during rest, reaction to sound, and perception to simple tones or chords from Smetana's symphonic poem Vysehrad. The length of reaction time was found dependent on FFT changes: the longer the time, the higher are the delta and the lower the alpha activities in the EEG spectrum. However, with alpha increasing during relaxation, the reaction time grew longer regardless of whether delta had increased due to hyperventilation, sleep or subclinical epileptic discharges. During the perception of tones, FFT showed changes in the alpha and delta bands different from those during the perception of chords, and different again during relaxation, and that in both normal controls and epileptics. The demented persons revealed no discernible FFT differences in the perception of either tones or chords, the only differences were found in the resting sections of the spectrum. One and the same stimulus produced a stereotype FFT response, i.e., different stimuli elicited different FFT response in healthy and epileptic persons. The dements responded to identical stimuli differently, and had stereotype FFT response elicited by the same stimuli. The results suggest that FFT can represent the information content of the EEG curve and, indirectly, also that of micro-EEG as it reverberates between the thalamus and the cortex in the form of neuronal activity impulsations. This interneuronal impulsation coding is disordered in dements with atrophy of the cortex; it is marked, on the one hand, by increased variability in the perception of identical stimuli, and, on the other hand, by impaired differentiation, and, consequently, by increasingly stereotype responses to different stimuli.


Asunto(s)
Enfermedad de Alzheimer/fisiopatología , Demencia por Múltiples Infartos/fisiopatología , Electroencefalografía , Epilepsia/fisiopatología , Potenciales Evocados , Adolescente , Adulto , Anciano , Corteza Cerebral/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tálamo/fisiopatología
9.
Radiology ; 176(2): 509-15, 1990 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2164237

RESUMEN

After birth the human brain is subject to major maturational changes, which are associated with changes in the biochemical composition of the brain and brain metabolism. Magnetic resonance (MR) spectroscopy has special capabilities in the analysis of in vivo metabolism. Volume-selective proton and phosphorus MR spectroscopy of the brain was performed on a 1.5-T magnet in 41 healthy children aged 1 month to 16 years. With advancing age, phosphorus spectra revealed a decrease in the ratios of phosphomonoesters (PMEs) to beta-adenosine triphosphate (ATP) and PMEs to phosphocreatine (PCr) and an increase in the ratios of phosphodiesters to beta-ATP, PCr to beta-ATP, and PCr to inorganic phosphate (Pi). No significant changes were observed in Pi/beta-ATP and pH. No changes occurred after the age of 3 years. Proton spectroscopy revealed an increase in the ratios of N-acetylaspartate (NAA) to choline (Ch) and NAA to creatine (Cr) and a decrease in Ch/Cr with increasing age. The most rapid changes were noted during the first 3 years of life, but changes were still observed at the age of 16 years.


Asunto(s)
Envejecimiento/metabolismo , Encéfalo/metabolismo , Espectroscopía de Resonancia Magnética , Fósforo/metabolismo , Protones , Adenosina Trifosfato/metabolismo , Adolescente , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Niño , Preescolar , Colina/metabolismo , Femenino , Humanos , Lactante , Masculino , Organofosfatos/metabolismo , Fosfocreatina/metabolismo
10.
Br Med J (Clin Res Ed) ; 296(6635): 1491-4, 1988 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-3134082

RESUMEN

A prospective randomised trial was carried out to see whether paranormal healing by laying on of hands might reduce blood pressure in essential hypertension and whether such an effect might be due to a paranormal, psychological, or placebo factor. Patients were randomised to three treatment groups: paranormal healing by laying on of hands (n = 40), paranormal healing at a distance (n = 37), and no paranormal healing (controls; n = 38). Healing at a distance and no paranormal healing were investigated double blind. Systolic and diastolic blood pressures were significantly reduced in all three groups at week 15 (mean reduction (95% confidence interval) 17.1 (14.0 to 20.2)/8.3 (6.6 to 10.0) mm Hg). Only the successive reductions in diastolic blood pressures among the groups from week to week were significantly different. Each week diastolic pressure was consistently lower (average 1.9 mm Hg) after healing at a distance compared with control, but on paired comparison these differences were not significant. Probably week to week variations among the groups accounted for any differences noted. In this study no treatment was consistently better than another and the data cannot therefore be taken as evidence of a paranormal effect on blood pressure. Probably the fall in blood pressure in all three groups either was caused by the psychosocial approach or was a placebo effect of the trial itself.


Asunto(s)
Hipertensión/terapia , Curación Mental , Presión Sanguínea , Ensayos Clínicos como Asunto , Femenino , Frecuencia Cardíaca , Humanos , Hipertensión/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Países Bajos , Estudios Prospectivos , Distribución Aleatoria
13.
Tijdschr Diergeneeskd ; 110(24): 1057-65, 1985 Dec 15.
Artículo en Holandés | MEDLINE | ID: mdl-2418528

RESUMEN

The effects of a number of factors on the concentration of gamma globulins in the serum of newborn calves were studied in 181 calves from six different dairy farms as was also the use of the refractometer test in controlling the ingestion of colostrum. The refractometer test was found to be reliable in controlling the concentration of gamma globulins in the serum of calves up to the sixth day of life. The factors 'time the first colostrum was ingested', 'amount of first colostrum ingested' and the 'concentration of gamma globulins in the colostrum' were found to account for 23.5 per cent of the variations in serum gamma globulin concentration; this became 42.4 per cent when the 'system of administration' and the 'farm-bound factors' were also taken into account. The first colostrum is best ingested when it is offered in a pail or bottle provided with a nipple. Calves of heifers were found to show a lower concentration of gamma globulins in the serum than did calves of older cows.


Asunto(s)
Animales Recién Nacidos/sangre , Bovinos/sangre , Calostro/análisis , Refractometría/métodos , gammaglobulinas/análisis , Alimentación Animal , Crianza de Animales Domésticos/métodos , Animales , Femenino , Masculino
14.
Hypertension ; 7(2): 216-22, 1985.
Artículo en Inglés | MEDLINE | ID: mdl-3980068

RESUMEN

The effects of nisoldipine administration on vascular reactivity to humoral and neural vasoconstrictor stimuli were examined in the intact rat. For these experiments, rats were instrumented with miniaturized pulsed Doppler flow probes to allow continuous measurement of renal, mesenteric, and hindquarters blood flow. In conscious and anesthetized rats, intravenous doses of angiotensin II (75 and 150 ng/kg), norepinephrine (0.6 and 1.2 microgram/kg), and epinephrine (0.6 and 1.2 microgram/kg) caused dose-dependent increases in arterial pressure and renal and mesenteric vascular resistance. Nisoldipine (0.7 microgram/min) administration significantly attenuated (p less than 0.05) the pressor and regional vasoconstrictor actions of all three circulating pressor agents; however, nisoldipine infusion had little effect on neurally mediated regional vasoconstrictor responses elicited by electrical stimulation of the posterior hypothalamus or greater splanchnic nerve. These data indicate that nisoldipine depressed vascular responsiveness to humoral vasoconstrictor agents, while neural vasoconstrictor responses were unaffected. Thus nisoldipine appears to exert preferential antagonistic effects on humoral rather than on neural vasoconstrictor stimuli.


Asunto(s)
Hipotálamo Posterior/fisiología , Hipotálamo/fisiología , Nifedipino/análogos & derivados , Nervios Esplácnicos/fisiología , Vasoconstricción/efectos de los fármacos , Vasodilatadores/farmacología , Angiotensina II/farmacología , Animales , Presión Sanguínea/efectos de los fármacos , Epinefrina/farmacología , Masculino , Arterias Mesentéricas/fisiología , Nifedipino/farmacología , Nisoldipino , Norepinefrina/farmacología , Ratas , Ratas Endogámicas , Arteria Renal/fisiología , Resistencia Vascular/efectos de los fármacos
15.
Am J Physiol ; 247(3 Pt 2): H349-60, 1984 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-6476129

RESUMEN

The increase in arterial pressure and vascular resistance during acute unilateral renal artery stenosis (RSt) in conscious rats is, in part, dependent on elevated neurogenic vascular tone produced by an indirect neural interaction of angiotensin II (ANG II) with the sympathetic nervous system. The present experiments examined whether this interaction occurs within the central nervous system. Conscious rats that had been chronically instrumented with miniaturized Doppler flow probes for measurement of regional vascular resistance were subjected to a 50% reduction in unilateral renal flow with an implanted pneumatic occluder. Arterial pressure increased by 35% after 60 min of RSt. In animals in which the pressor response to intracerebroventricular (icv) ANG II had been eliminated by prior surgical interruption of the "ANG II pressor pathway" in the anterior hypothalamus, the increase in blood pressure following RSt was attenuated by 44% (P less than 0.01). In a second series, a central action of ANG II during acute renal hypertension (RH) was assessed by central ANG II receptor blockade with icv saralasin. Unlike normotensive controls, acutely RH animals responded to saralasin with significant (P less than 0.01) decreases in arterial pressure (-32%) and hindquarters (-26%) and contralateral renal (-9%) resistance. These changes were accentuated (-57% decrease in pressure) in animals made areflexic by prior sinoaortic baroreceptor denervation. Thus activation of the sympathetic nervous system during the early high-renin phase of RH depends significantly on a central action of ANG II. This mechanism may account for some 40-50% of the pressure increase following acute RSt.


Asunto(s)
Angiotensina II/fisiología , Sistema Nervioso Central/fisiopatología , Hipertensión Renal/fisiopatología , Vías Aferentes/fisiopatología , Animales , Seno Carotídeo/fisiopatología , Estado de Conciencia , Constricción Patológica , Hipotálamo/fisiopatología , Masculino , Bloqueo Nervioso , Presorreceptores/fisiopatología , Ratas , Ratas Endogámicas , Receptores de Angiotensina/efectos de los fármacos , Reflejo/fisiología , Obstrucción de la Arteria Renal/fisiopatología , Saralasina/farmacología
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