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1.
Br Poult Sci ; 62(2): 270-277, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33155822

RESUMEN

1. The impact of feeding sources of n-3 fatty acids (FA) to ISA Brown and Shaver White breeders and their offspring on antibody titres and plasma FA profile was examined.2. Breeders were fed either a control diet (CON); CON + 1% microalgae (DMA: Aurantiochytrium limacinum) as a source of docosahexaenoic acid; or CON + 2.6% of a co-extruded mixture of full-fat flaxseed (FFF) as a source of α-linolenic acid. Day-old female offspring were assigned to diets (breeder-offspring): 1) CON-CON, 2) CON-DMA, 3) CON - FFF, 4) DMA - CON, 5) DMA - DMA, 6) FFF - CON or 7) FFF - FFF, followed by a standard layer diet through 18 weeks of age (WOA) to 42 WOA.3. Antibody titres against infectious bronchitis (IBV) and Newcastle disease (NDV) were measured at six days and six WOA, and plasma FA profile was measured at 18 and 42 WOA.4. Pullets from FFF-fed breeders had higher antibody titres against IBV and NDV than pullets fed DMA (P < 0.05). Feeding FFF to offspring increased plasma ∑n-3 FA at 18 and 42 WOA, whereas feeding DMA to offspring reduced ∑n-6 FA at 18 WOA.5. In conclusion, independent of breeder strain, alpha linoleic acid (ALA) and DHA sources showed varied responses. Feeding breeders FFF increased plasma concentration of antibody titres and n-3 FA whereas DMA reduced plasma concentration of ∑n-6 FA.


Asunto(s)
Bronquitis , Ácidos Grasos Omega-3 , Enfermedad de Newcastle , Alimentación Animal/análisis , Animales , Bronquitis/veterinaria , Pollos , Dieta/veterinaria , Ácidos Grasos , Femenino , Plasma
2.
Poult Sci ; 99(8): 3959-3970, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32731983

RESUMEN

The impact of feeding sources of n-3 fatty acids (FA) to ISA brown and Shaver white breeders and their female offspring during rearing on egg production, eggshell, tibia, and keel bone attributes was examined. Breeders were fed Control (CON) or CON + 1% dried microalgae (DMA: Aurantiochytrium limacinum) as the source of docosahexaenoic acid or CON + 2.6% of a coextruded mixture of full-fat flaxseed (FFF) and pulses as a source of α-linolenic acid. Day-old offspring were fed 1) breeder CON-pullet CON (CON-CON), 2) breeder CON-pullet DMA (CON-DMA), 3) breeder CON-pullet FFF (CON-FFF), 4) breeder DMA-pullet CON (DMA-CON), 5) breeder DMA-pullet DMA (DMA-DMA), 6) breeder FFF-pullet CON (FFF-CON), and 7) breeder FFF-pullet FFF (FFF-FFF). At 18 wk of age (WOA), pullets were fed a common layer diet to 42 WOA for egg production and bone quality assessments. There was no (P > 0.05) interaction between strains and diets and the main effect of diets on egg production, egg mass, and eggshell quality. There was an interaction (P = 0.008) between strain and diet on egg weight (EW); however, the strain effect on EW (P < 0.001) was such that ISA brown had heavier eggs than Shaver white. Shaver white had higher (P < 0.001) eggshell %, eggshell, and tibia breaking strength (BS), as well as tibia ash concentration compared with ISA brown hens. In contrast, ISA brown hens exhibited heavier (P < 0.05) tibia and keel bones. Feeding breeders DMA and pullets both sources of n-3 FA increased tibia medullary ash concentration compared with other diets (P < 0.001). Shaver white hens showed greater decline in tibia BS (83.7 vs. 96.3%) and ash content (84.1 vs. 94.3%) than ISA brown hens from 18 to 42 WOA (P < 0.05). Strain and diets exhibited independent effects on eggshell, tibia, and keel attributes. Provision of α-linolenic acid and docosahexaenoic acid to breeders and offspring improved tibia medullary ash concentration at 42 WOA.


Asunto(s)
Alimentación Animal , Huesos , Pollos , Cáscara de Huevo , Ácidos Grasos Omega-3 , Oviposición , Alimentación Animal/análisis , Animales , Huesos/efectos de los fármacos , Pollos/crecimiento & desarrollo , Dieta/veterinaria , Cáscara de Huevo/efectos de los fármacos , Ácidos Grasos Omega-3/farmacología , Femenino , Oviposición/efectos de los fármacos
3.
Poult Sci ; 99(4): 2087-2099, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32241494

RESUMEN

Impact of feeding n-3 fatty acids (FA) to ISA brown and Shaver white breeders and their progeny on bone development in pullets was investigated. Breeders were fed Control (CON); CON + 1% microalgae (DMA: Aurantiochytrium limacinum) as the source of docosahexaenoic acid; and CON + 2.6% of a co-extruded mixture of full-fat flaxseed (FFF) and pulses mixture as source of α-linolenic acid. Test diets (DMA and FFF) were balanced for total n-3 FA and n-6: n-3 FA ratio. Samples of day-old progeny were euthanized for bone mineral content (BMC) and tibia collagen type II. The remaining pullets were fed posthatch treatments as follows: from breeder CON: CON (CON-CON), DMA (CON-DMA), and FFF (CON-FFF), from breeder DMA: CON (DMA-CON) and DMA (DMA-DMA) and from breeder FFF: CON (FFF-CON) and FFF (FFF-FFF). A total of 60 pullets per posthatch diets were reared in cages (12 pullets/cage, n = 5) with free access to feed and water, bled at 6, 12, and 18 wk of age (WOA) for bone turnover markers and necropsied at 18 WOA for tibia and femur samples. Day-old pullets from breeder fed CON had greater BMC (P < 0.001) relative to those from breeders fed other diets. There was strain and diet interaction (P ≤ 0.024) on tibia breaking strength (TBS) and tibia cortical ash concentration at 18 WOA such that diet responses were only observed in Shaver white pullets. In this context, TBS of DMA-DMA and FFF-FFF was greater than for pullets originating from CON breeder, and the cortical ash weight of DMA-DMA and FFF-FFF pullets was 23.8 and 20.2%, respectively, higher than for CON-CON pullets. In conclusions, the strain effects were strong on tibia attributes on 18-week-old pullets. Breeder feeding of n-3 FA was more effective when concomitant with posthatch feeding of n-3 FA in supporting the skeletal strength and cortical bone development in Shaver white pullets. Further investigations are warranted to establish the impact these strategies on skeletal health during laying cycle.


Asunto(s)
Alimentación Animal/análisis , Pollos/crecimiento & desarrollo , Ácidos Grasos Omega-3/metabolismo , Lino/química , Microalgas/química , Esqueleto/crecimiento & desarrollo , Estramenopilos/química , Animales , Dieta/veterinaria , Suplementos Dietéticos/análisis , Femenino , Masculino , Esqueleto/efectos de los fármacos
4.
Bone Joint J ; 101-B(6): 635-638, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31154832

RESUMEN

AIMS: The aim of this study was to review the value of accepting referrals for children with 'clicky hips' in a selective screening programme for hip dysplasia. PATIENTS AND METHODS: A single-centre prospective database of all referrals to the hip clinic was examined to identify indication for referrals, diagnosis, and treatment. All patients referred received a standardized ultrasound scan and clinical examination by an orthopaedic consultant. RESULTS: There were 5716 children referred to the orthopaedic hip clinic between 1 June 2014 and 26 September 2018. In all, 1754 children (30.1%) were referred due to 'clicky hip' with no additional risk factors or indications for ultrasound scan. A total of 123 children (7.1%) referred with 'clicky hip' and no additional risk factors or examination findings had an abnormal initial hip ultrasound, including 16 children (0.9%) with dysplastic hips. Of the 141 children who required treatment in a Pavlik harness during the study period, 23 (16%) had been referred with a 'clicky hip' and no additional risk factors or examination findings, including six children with Graf 3 or 4 hips. CONCLUSION: There is significant value in reviewing children with an isolated 'clicky hip'. Many children who require treatment are referred to the orthopaedic service as 'clicky hip' with no additional risk factors. In a pragmatic pathway with a diverse population of clinicians performing baby checks, 'clicky hip' is an important indication for referral and should not be discarded. Cite this article: Bone Joint J 2019;101-B:635-638.


Asunto(s)
Luxación Congénita de la Cadera/diagnóstico , Diagnóstico Diferencial , Femenino , Luxación Congénita de la Cadera/terapia , Humanos , Lactante , Recién Nacido , Masculino , Examen Físico , Estudios Prospectivos , Factores de Riesgo , Ultrasonografía
5.
Bone Joint J ; 98-B(1): 131-6, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26733526

RESUMEN

UNLABELLED: A retrospective study was performed in 100 children aged between two and 16 years, with a dorsally angulated stable fracture of the distal radius or forearm, who were treated with manipulation in the emergency department (ED) using intranasal diamorphine and 50% oxygen and nitrous oxide. Pre- and post-manipulation radiographs, the final radiographs and the clinical notes were reviewed. A successful reduction was achieved in 90 fractures (90%) and only three children (3%) required remanipulation and Kirschner wire fixation or internal fixation. The use of Entonox and intranasal diamorphine is safe and effective for the closed reduction of a stable paediatric fracture of the distal radius and forearm in the ED. By facilitating discharge on the same day, there is a substantial cost benefit to families and the NHS and we recommend this method. TAKE HOME MESSAGE: Simple easily reducible fractures of the distal radius and forearm in children can be successfully and safely treated in the ED using this approach, thus avoiding theatre admission and costly hospital stay.


Asunto(s)
Analgésicos Opioides/administración & dosificación , Anestésicos Combinados/administración & dosificación , Traumatismos del Antebrazo/terapia , Heroína/administración & dosificación , Manipulación Ortopédica/métodos , Óxido Nitroso/administración & dosificación , Oxígeno/administración & dosificación , Administración Intranasal , Adolescente , Niño , Preescolar , Servicio de Urgencia en Hospital , Femenino , Traumatismos del Antebrazo/diagnóstico por imagen , Humanos , Masculino , Radiografía , Fracturas del Radio/diagnóstico por imagen , Fracturas del Radio/terapia , Estudios Retrospectivos
6.
Bone Joint J ; 95-B(6): 846-50, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23723283

RESUMEN

Most centres in the United Kingdom adopt a selective screening programme for developmental dysplasia of the hip (DDH) based on repeated clinical examination and selective ultrasound examination. The Newborn Infant Physical Examination protocol implemented in 2008 recommends a first examination at birth and then a second and final examination at six to ten weeks of age. Due to concerns over an increase in late presentations we performed a retrospective review of our 15-year results to establish if late presentation increases treatment requirements. Of children presenting before six weeks of age, 84% were treated successfully with abduction bracing, whereas 86% of children presenting after ten months eventually required open reduction surgery. This equates to a 12-fold increase in relative risk of requiring open reduction following late presentation. Increasing age at presentation was associated with an increase in the number of surgical procedures, which are inevitably more extensive and complex, with a consequent increased in cost per patient. The implementation of an opportunistic examination at three to five months could help to reduce the unintended consequences of the Newborn Infant Physical Examination programme.


Asunto(s)
Artroplastia de Reemplazo de Cadera/tendencias , Luxación Congénita de la Cadera/diagnóstico , Tamizaje Neonatal/normas , Guías de Práctica Clínica como Asunto , Preescolar , Femenino , Estudios de Seguimiento , Luxación Congénita de la Cadera/epidemiología , Luxación Congénita de la Cadera/cirugía , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Estudios Retrospectivos , Reino Unido/epidemiología
7.
J Agric Food Chem ; 48(9): 3957-64, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10995297

RESUMEN

Eight varieties of lettuce (Lactuca sativum) and three varieties of endive (Cichorium endivia) were analyzed for flavonoid composition and content. Total flavonoid contents, expressed as units of aglycon for fresh material, were in the ranges of 0.3-229 microg/g for lettuce and 44-248 microg/g for endive. Five quercetin conjugates [quercetin 3-O-galactoside, quercetin 3-O-glucoside, quercetin 3-O-glucuronide, quercetin 3-O-(6-O-malonyl)glucoside, and quercetin 3-O-rhamnoside] and luteolin 7-O-glucuronide were measured in the green-leafed lettuce and an additional two cyanidin conjugates [cyanidin 3-O-glucoside and cyanidin 3-O-[(6-O-malonyl)glucoside]] in the red-leafed varieties. Three kaempferol conjugates [kaempferol 3-O-glucoside, kaempferol 3-O-glucuronide, and kaempferol 3-O-[6-O-malonyl)glucoside]] were measured in each of the endive varieties. The presence and identity of kaempferol 3-O-(6-O-malonyl)glucoside in endive was shown for the first time. Shredding of lettuce leaf followed by exposure to light produced significant losses of the flavonoid moiety in the green oak leaf (94%), red oak leaf (43%), iceberg (36%), green batavia (25%), lollo biondo (24%), and lollo rosso (6%) samples, whereas cos and green salad bowl samples did not show an overall loss. Shredding of endive also produced loss of the flavonoid moiety in escarole (32%), fine frisee (13%), and coarse frisee (8%). Significant demalonation was observed for both the quercetin and cyanidin glucosides in lettuce, whereas a similar degradation of the kaempferol analogue was found in endive tissue. Storage of whole heads of both lettuce and endive in the dark at 1 degrees C and 98% humidity for 7 days resulted in losses of total flavonol glycosides in the range of 7-46%. The identification of the amounts, position of substitution, and nature of the sugars is important for understanding the potential bioavailability and biological activities of flavonoids in salads.


Asunto(s)
Flavonoides/análisis , Manipulación de Alimentos , Glicósidos/análisis , Lactuca/química , Cromatografía Líquida de Alta Presión , Espectrometría de Masas
8.
Redox Rep ; 4(3): 123-7, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10496415

RESUMEN

We have examined the antioxidant activity of one class of polyphenolic compounds in green beans: two novel flavonol glycosides (quercetin 3-O-[xylosyl(1-->2)]-rhamnosyl (1-->6)-glucoside and the corresponding kaempferol analogue), quercetin 3-O-glucuronide, kaempferol 3-O-glucuronide, quercetin 3-O-rutinoside and kaempferol 3-O-rutinoside. The Trolox equivalent antioxidant capacity (TEAC) and inhibition of iron/ascorbate-induced lipid peroxidation of phosphatidyl choline vesicles were measured. In the aqueous phase TEAC assay, the glucuronide and rutinoside of quercetin were good antioxidants, but not as effective as the quercetin aglycone. TEAC values for the glucuronide and other glycosides of kaempferol were much lower than the corresponding quercetin species but similar to that of the kaempferol aglycone. Quercetin 3-O-glucuronide and quercetin 3-O-rutinoside were both potent inhibitors of lipid peroxidation, in contrast to the those of kaempferol. The compounds described herein demonstrate the antioxidant activity of the flavonols present in green beans and indicate the effect on antioxidant activity of sugar substitutions in the phenolic C ring.


Asunto(s)
Antioxidantes/química , Fabaceae/química , Flavonoides/química , Glicósidos/química , Quempferoles , Plantas Medicinales , Antioxidantes/aislamiento & purificación , Secuencia de Carbohidratos , Cromanos/química , Flavonoides/aislamiento & purificación , Flavonoles , Glicósidos/aislamiento & purificación , Cinética , Datos de Secuencia Molecular , Quercetina/análogos & derivados , Quercetina/química , Relación Estructura-Actividad
9.
Redox Rep ; 4(1-2): 13-6, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10714270

RESUMEN

We have determined the antioxidant activity of the major flavonols found in tea: a monoglycoside, a diglycoside and two triglycosides of kaempferol and three monoglycosides, a diglycoside and two triglycosides of quercetin. The Trolox equivalent antioxidant capacity (TEAC) and inhibition of iron/ascorbate-induced lipid peroxidation of phosphatidyl choline vesicles were measured. In the aqueous phase TEAC assay, the quercetin monoglycosides and diglycoside were approximately half as effective as quercetin aglycone. The quercetin triglycosides were much less effective than the monoglycosides and the diglycoside. The kaempferol glycosides were 32-39% less effective in the aqueous phase antioxidant assay compared to the kaempferol aglycone. Quercetin monoglycosides and diglycoside were potent inhibitors of lipid peroxidation, in contrast to the triglycoside which was much less effective. All the kaempferol glycosides were significantly less potent inhibitors of lipid peroxidation compared to the kaempferol aglycone. The compounds described herein demonstrate the antioxidant activity of the major flavonols in tea and indicate the effect of substituting a range of sugar moieties in the phenolic C ring.


Asunto(s)
Antioxidantes/farmacología , Flavonoides/farmacología , Glicósidos/farmacología , Té/química , Flavonoles , Peroxidación de Lípido/efectos de los fármacos
10.
Eur J Cancer Prev ; 6(6): 518-21, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9496452

RESUMEN

Food plants contain a range of nutrient and non-nutrient compounds with antioxidant properties. Principal among these compounds are flavonols and the cinnamic acid derivatives. These two groups exist in plant foods largely as conjugates with sugars or with organic acids; and typically, plant foods contain complex mixtures of these glycosides and conjugates. The analysis of such mixtures in foods is an important outstanding problem. The present paper outlines methods for the extraction and purification of phenolic antioxidants as the conjugated forms that exist in plant foods.


Asunto(s)
Flavonoides/análisis , Flavonoides/aislamiento & purificación , Plantas Comestibles , Disponibilidad Biológica , Cinamatos/análisis , Cinamatos/aislamiento & purificación , Flavonoles , Glicosilación , Humanos , Reino Unido
11.
Cancer Lett ; 120(2): 213-6, 1997 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-9461039

RESUMEN

Some flavonoids induce phase II enzymes both in vivo and in vitro. We have determined the structural requirements for this activity by examining the ability of naturally-occurring flavonoids to induce the phase II enzyme, quinone reductase (NAD(P)H:quinone oxidoreductase; EC 1.6.99.2), in murine Hepalclc7 cells. Hydroxylation of the B ring is not essential for induction, since galangin and kaempferol (with 0 and 1 hydroxyl in the B ring, respectively) are better inducers than quercetin (2 B ring hydroxyls). A 2,3 double bond in the C ring is essential for induction, since taxifolin, which has the same substitution pattern as quercetin but lacks the 2,3 double bond, is not an inducer. This is supported by catechin and epicatechin, which do not possess the 2,3 double bond and are also not inducers. A 3-hydroxyl group increases the activity but is not essential for induction, since apigenin is an inducer but kaempferol (which has the same structure as apigenin but possesses a 3-hydroxyl group) is more effective. The data show that, of the flavonoids, the flavonols are the most effective inducers of quinone reductase activity in Hepa1c1c7 cells (kaempferol approximately galangin > quercetin > myricetin approximately apigenin (a flavone)) and that flavanols and flavans are ineffective.


Asunto(s)
Flavonoides/farmacología , Quempferoles , Neoplasias Hepáticas Experimentales/enzimología , NAD(P)H Deshidrogenasa (Quinona)/biosíntesis , Animales , Catequina/farmacología , Manzanilla , Inducción Enzimática/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Flavonoides/química , Flavonoles , Ratones , Aceites Volátiles/farmacología , Plantas Medicinales , Quercetina/análogos & derivados , Quercetina/farmacología , Células Tumorales Cultivadas
12.
Free Radic Res ; 27(4): 429-35, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9416471

RESUMEN

We have examined the antioxidant activity of the major phenolic compounds in Broccoli: two flavonol glycosides (quercetin 3-O-sophoroside and kaempferol 3-O-sophoroside) and four hydroxycinnamic acid esters (1,2'-disinapoyl-2-feruloyl gentiobiose, 1-sinapoyl-2-feruloyl gentiobiose, 1,2,2'-trisinapoyl gentiobiose and 1,2-disinapoyl gentiobiose). The Trolox C equivalent antioxidant capacity (TEAC) and inhibition of iron/ascorbate-induced lipid peroxidation of phosphatidyl choline vesicles were measured. In the aqueous phase TEAC assay, the two flavonol glycosides were less active than their respective aglycones. TEAC values for the hydroxycinnamic acid esters were less than the sum of their constituent hydroxycinnamic acids on a molar basis. Quercetin 3-O-sophoroside was a potent inhibitor of lipid peroxidation, in contrast to kaempferol 3-O-sophoroside. The hydroxycinnamic acid esters were highly effective at preventing lipid damage with the exception of 1,2,2'-trisinapoyl gentiobiose. The six compounds analysed herein demonstrate the antioxidant activity of the major phenolics in broccoli and indicate the effect on antioxidant activity of sugar substitutions in the phenolic B ring.


Asunto(s)
Antioxidantes , Brassica/química , Fenoles/química
13.
Carcinogenesis ; 17(11): 2385-7, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8968052

RESUMEN

It has recently been shown by Hollman et al. (Am. J. Clin. Nutr., 62, 1276-1282) that flavonoid glycosides are preferentially absorbed from dietary onions compared to the flavonoid aglycone. In the light of this, we have compared the bioactivities of the two most abundant flavonoid glycosides that we have purified from onions (quercetin-3,4'-diglucoside and quercetin-4'-glucoside) to the quercetin aglycone, and also to the more commonly studied commercially-available flavonoid glycosides, rutin (quercetin-3-rutinoside) and isoquercitrin (quercetin-3-glucoside). Quercetin aglycone was the most effective inducer of the anticarcinogenic phase II marker enzyme, quinone reductase (QR), in mouse Hepalclc7 cells. Of the glycosides, only quercetin-4'-glucoside was able to induce QR activity in this assay. Inhibition of NADPH/iron- and ascorbate/iron-induced lipid peroxidation of human liver microsomes, and the Trolox C-equivalent antioxidant capacity (TEAC), were also measured. The 4'-glycosylation dramatically decreased activity in the 'antioxidant' assays, whereas 3-substitutions produced much smaller changes. These results show that the preferentially-absorbed quercetin glycosides in onions have markedly different biological properties compared with the aglycone.


Asunto(s)
Anticarcinógenos/farmacología , Antioxidantes/farmacología , Glicósidos/farmacología , Microsomas Hepáticos/efectos de los fármacos , Microsomas Hepáticos/enzimología , NAD(P)H Deshidrogenasa (Quinona)/biosíntesis , Quercetina/análogos & derivados , Animales , Cromanos/farmacología , Inducción Enzimática/efectos de los fármacos , Glicosilación , Humanos , Peroxidación de Lípido , Ratones , Quercetina/farmacología
16.
J Chromatogr A ; 719(1): 213-9, 1996 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-8589830

RESUMEN

A capillary zone electrophoretic (CZE) method is described for the analysis of the raffinose family of oligosaccharides (RFO) in pea seeds. Extraction of RFO was carried out in 80% ethanol and the extract was passed through a Sep-Pak C18 cartridge. This proved to be an improvement on the currently accepted purification technique. High-quality electrophoregrams were obtained which allowed the separation and quantitation of sucrose, raffinose, stachyose and verbascose The CZE results were compared with those obtained by anion-exchange high-performance liquid chromatography coupled to a triple-pulsed amperometric detection (HPAC-PAD). The samples were obtained from four pea strains which were near-isogenic except for genes at the r and rb loci. A high degree of precision and reproducibility was obtained for the RFO compositions of all the pea strains. No statistically significant differences (p < or equal to 0.05) were found between the two analytical techniques using paired Student-t tests.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Electroforesis Capilar/métodos , Fabaceae/química , Galactósidos/análisis , Plantas Medicinales , Semillas/química , Oligosacáridos/análisis , Rafinosa/análisis , Sacarosa/análisis
17.
Toxicol In Vitro ; 10(2): 117-28, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20650190

RESUMEN

The effects of potato and tomato glycoalkaloids and a saponin mixture from Gypsophila were investigated in cytotoxicity studies (neutral red uptake, mitochondrial MTT reduction and release of lactate dehydrogenase), using cultured cell lines of rat and human intestinal mucosal epithelium. Experiments to assess the effects of these compounds on the integrity of the intestinal epithelium were also carried out using preparations of isolated rat jejunum in vitro. By investigating the effect of these compounds on cultured cells and on intestinal tissue preparations, changes in membrane integrity, as evidenced by lactate dehydrogenase leakage in cell culture, could be confirmed in a system more relevant to the whole gut. Of the compounds tested, alpha-tomatine was consistently the most potent in all tests, and indications of a synergistic effect on membrane depolarization were observed between alpha-chaconine and alpha-solanine at total glycoalkaloid concentrations of less than 1 mM (< 0.86 mg/ml), with an optimum when the former comprised 25% of the mixture. An increase in the apparent permeability of the brush border was observed at sublethal concentrations of the compounds, and this may have important implications with respect to enhanced uptake of macromolecules, such as allergens, whose passage through the epithelium is normally somewhat restricted.

18.
J Am Soc Mass Spectrom ; 7(2): 173-81, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24203239

RESUMEN

Four aglycons (tomatidine, demissidine, solanidine, and solasodine) and three glycoalkaloids (α-tomatine, α-chaconine, and α-solanine) have been analyzed by positive ion liquid secondary ion high-energy and low-energy collision-induced dissociation (CID) tandem mass Spectrometry, performed on a four-sector (EBEB) and a hybrid (EBQQ) instrument, respectively. Both high- and low-energy collision-induced dissociation mass spectra of [M+H](+) ions of these compounds provided structural information that aided the characterization of the different aglycons and of the carbohydrate sequence and linkage sites in the glycoalkaloids. Low-energy CID favors charge-driven fragmentation of the aglycon rings, whilst high-energy CID spectra are more complex and contain additional ions that appear to result from charge-remote fragmentations, multiple cleavages, or complex charge-driven rearrangements. With respect to the structural characterization of the carbohydrate part, low-energy CID fragmentations of sugar residues in the glycoalkaloids generate Y n (+) ions and some low intensity Z n (+) ions; the high-energy spectra also exhibit strong (1,5)X n (+) ions, formed by multiple cleavage of the sugar ring, and significant Z n (+) ions.

20.
Aviat Space Environ Med ; 65(6): 527-30, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8074626

RESUMEN

Virtual reality (VR) has become increasingly well-known over the last few years. However, little is known about the side-effects of prolonged immersion in VR. This study set out to investigate the frequency of occurrence and severity of side-effects of using an immersion VR system. Out of 146 subjects, 61% reported symptoms of malaise at some point during a 20-min immersion and 10-min post-immersion period. These ranged from symptoms such as dizziness, stomach awareness, headaches, eyestrain and lightheadedness to severe nausea. These symptoms caused 5% of the subjects to withdraw from the experiment before completing their 20-min immersion period. Further research needs to be conducted that attempts to identify those factors that play a causative role in the side-effects of the VR system, and that looks for methods of reducing these side-effects.


Asunto(s)
Astenopía/etiología , Simulación por Computador , Mareo/etiología , Cefalea/etiología , Náusea/etiología , Índice de Severidad de la Enfermedad , Medicina Aeroespacial , Astenopía/clasificación , Astenopía/epidemiología , Astenopía/fisiopatología , Mareo/clasificación , Mareo/epidemiología , Mareo/fisiopatología , Estudios de Evaluación como Asunto , Femenino , Cefalea/clasificación , Cefalea/epidemiología , Cefalea/fisiopatología , Humanos , Masculino , Náusea/clasificación , Náusea/epidemiología , Náusea/fisiopatología
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