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1.
Appl Spectrosc ; 77(12): 1411-1423, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37801484

RESUMEN

Spatial heterodyne Raman spectrometers (SHRSs) are modified forms of Michelson interferometers, except the mirrors in a Michelson interferometer are replaced with stationary diffraction gratings. This design removes the need for an entrance slit, as is the case in a dispersive spectrometer, and removes the need to scan the spectrum by using a moving mirror in a modern Michelson interferometer. In previous studies, various SHRS variants, such as free-standing two-grating SHRS, single-grating SHRS (1g-SHRS), monolithic SHRS (mSHRS), and single-grating mSHRS (1g-mSHRS), have been evaluated. However, the present study exclusively focuses on the 1g-mSHRS configuration. The 1g-mSHRS and 1g-SHRS increase the spectral range at fixed grating line density while trading off spectral resolution and resolving power. The mSHRS benefits from increased rigidity, lack of moving parts, and reduced footprint. In this study, we investigate how the choice of detector impacts the performance of the 1g-mSHRS system, with a specific focus on evaluating the performance of three types of cameras: charged-coupled device (CCD), intensified CCD (ICCD), and complementary metal-oxide-semiconductor (CMOS) cameras. These systems were evaluated using geological, organic, and inorganic samples using a 532 nm continuous wave laser for the CMOS and CCD cameras, and a 532 nm neodymium-doped yttrium aluminum garnet pulsed laser for the ICCD camera. The footprint of the 1g-mSHRS was 3.5 × 3.5 × 2.5 cm3 with a mass of 272 g or 80 g, depending on whether the monolith housing is included or not. We found that increasing the number of pixels utilized along the x-axis of the camera increases fringe visibility (FV) and optimizes the resolution (by capturing the entirety of the grating and magnifying the fringes). The number of pixels utilized in the y-axis, chip size, and dimensions, affect the signal-to-noise ratio of the systems. Additionally, we discuss the effect of pixel pitch on the recovery of Fizeau fringes, including the relationship between the Nyquist frequency, aliasing, and FV.

2.
Protein Sci ; 30(11): 2206-2220, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34558135

RESUMEN

Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) is a pathogenic coronavirus causing COVID-19 infection. The interaction between the SARS-CoV-2 spike protein and the human receptor angiotensin-converting enzyme 2, both of which contain several cysteine residues, is impacted by the disulfide-thiol balance in the host cell. The host cell redox status is affected by oxidative stress due to the imbalance between the reactive oxygen/nitrogen species and antioxidants. Recent studies have shown that Vitamin D supplementation could reduce oxidative stress. It has also been proposed that vitamin D at physiological concentration has preventive effects on many viral infections, including COVID-19. However, the molecular-level picture of the interplay of vitamin D deficiency, oxidative stress, and the severity of COVID-19 has remained unclear. Herein, we present a thorough review focusing on the possible molecular mechanism by which vitamin D could alter host cell redox status and block viral entry, thereby preventing COVID-19 infection or reducing the severity of the disease.


Asunto(s)
COVID-19 , Estrés Oxidativo/efectos de los fármacos , SARS-CoV-2/metabolismo , Índice de Severidad de la Enfermedad , Internalización del Virus/efectos de los fármacos , Vitamina D/uso terapéutico , Enzima Convertidora de Angiotensina 2/metabolismo , COVID-19/metabolismo , COVID-19/patología , COVID-19/prevención & control , Humanos , Especies de Nitrógeno Reactivo/metabolismo , Especies Reactivas de Oxígeno/metabolismo
3.
Appl Spectrosc ; 75(11): 1427-1436, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34309445

RESUMEN

We have developed a compact instrument called the "COmpact COlor BIofinder", or CoCoBi, for the standoff detection of biological materials and organics with polyaromatic hydrocarbons (PAHs) using a nondestructive approach in a wide area. The CoCoBi system uses a compact solid state, conductively cooled neodymium-doped yttrium aluminum garnet (Nd:YAG) nanosecond pulsed laser capable of simultaneously providing two excitation wavelengths, 355 and 532 nm, and a compact, sensitive-gated color complementary metal-oxide-semiconductor camera detector. The system is compact, portable, and determines the location of biological materials and organics with PAHs in an area 1590 cm2 wide, from a target distance of 3 m through live video using fast fluorescence signals. The CoCoBi system is highly sensitive and capable of detecting a PAH concentration below 1 part per billion from a distance of 1 m. The color images provide the simultaneous detection of various objects in the target area using shades of color and morphological features. We demonstrate that this unique feature successfully detected the biological remains present in a 150-million-year-old fossil buried in a fluorescent clay matrix. The CoCoBi was also successfully field-tested in Hawaiian ocean water during daylight hours for the detection of natural biological materials present in the ocean. The wide-area and video-speed imaging capabilities of CoCoBi for biodetection may be highly useful in future NASA rover-lander life detection missions.


Asunto(s)
Láseres de Estado Sólido , Fluorescencia , Fósiles , Hidrocarburos
4.
Am J Physiol Endocrinol Metab ; 313(4): E381-E390, 2017 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-28679621

RESUMEN

Restricted growth before birth (IUGR) increases adult risk of Type 2 diabetes by impairing insulin sensitivity and secretion. Altered fetal one-carbon metabolism is implicated in developmental programming of adult health and disease by IUGR. Therefore, we evaluated effects of maternal dietary supplementation with methyl donors and cofactors (MMDS), designed to increase fetal supply, on insulin action in the spontaneously IUGR twin lamb. In vivo glucose-stimulated insulin secretion and insulin sensitivity were measured at days 12-14 in singleton controls (CON, n = 7 lambs from 7 ewes), twins (IUGR, n = 8 lambs from 8 ewes), and twins from ewes that received MMDS (2 g rumen-protected methionine, 300 mg folic acid, 1.2 g sulfur, 0.7 mg cobalt) daily from 120 days after mating (~0.8 of term) until delivery (IUGR+MMDS, n = 8 lambs from 4 ewes). Body composition and pancreas morphometry were assessed in lambs at day 16 IUGR reduced size at birth and increased neonatal fractional growth rate. MMDS normalized long bone lengths but not other body dimensions of IUGR lambs at birth. IUGR did not impair glucose control or insulin action at days 12-14, compared with controls. MMDS increased metabolic clearance rate of insulin and increased ß-cell numerical density and tended to improve insulin sensitivity, compared with untreated IUGR lambs. This demonstrates that effects of late-pregnancy methyl donor supplementation persist until at least the third week of life. Whether these effects of MMDS persist beyond early postnatal life and improve metabolic outcomes after IUGR in adults and the underlying mechanisms remain to be determined.


Asunto(s)
Cobalto/farmacología , Retardo del Crecimiento Fetal , Ácido Fólico/farmacología , Resistencia a la Insulina , Células Secretoras de Insulina/efectos de los fármacos , Insulina/metabolismo , Metionina/farmacología , Embarazo Gemelar , Azufre/farmacología , Animales , Animales Recién Nacidos , Glucemia/efectos de los fármacos , Glucemia/metabolismo , Composición Corporal/efectos de los fármacos , Estudios de Casos y Controles , Recuento de Células , Diabetes Mellitus Tipo 2/metabolismo , Suplementos Dietéticos , Femenino , Humanos , Páncreas/efectos de los fármacos , Embarazo , Efectos Tardíos de la Exposición Prenatal/metabolismo , Ovinos
5.
J Anim Sci ; 94(1): 96-105, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26812316

RESUMEN

The preweaning litter environment of gilts can affect subsequent development. In a recent experiment designed to test the effects of diet on gilt development, litter-of-origin traits including individual birth weights, immunocrits (a measure of colostrum intake), sow parity, number weaned, and individual weaning weights were collected for approximately 1,200 gilts that were progeny of approximately 300 sows. Subsequently, BW, LM area, and backfat were measured at 100 d of age and at 28-d intervals until slaughter (260 d of age). From 160 d of age to slaughter, gilts were observed daily for estrus. At slaughter, the reproductive tract and 1 mammary gland were recovered. The reproductive tract was classified as cyclic or prepubertal; the number of corpora lutea was counted. Uterine horn lengths and ovarian dimensions were measured. Uterus and ovary samples from every 10th gilt were prepared for histological evaluation of uterine gland development and follicle counts, respectively. Mammary gland tissue protein and fat were assayed. Day of the estrous cycle at slaughter was calculated using the first day of the most recent standing estrus (d 0) recorded previous to slaughter. Each gilt development trait was analyzed for association with each litter-of-origin trait, after adjusting for dietary treatment effects. Uterine length, ovarian dimensions, mammary gland protein and fat, and uterine gland development were also adjusted for day of the estrous cycle at slaughter. All litter-of-origin traits were associated ( < 0.05) with growth traits. Top-down (backward elimination) multiple regression analysis indicated that BW and LM accretion in gilts was positively associated with immunocrit ( < 0.01), birth weight ( < 0.01), preweaning growth rate ( < 0.01), and parity ( < 0.01). Backfat accretion was positively associated with preweaning growth rate ( < 0.01), number weaned ( < 0.05), and parity ( < 0.05). Age at puberty was associated with birth weight (positive; < 0.01) and preweaning growth rate (negative; < 0.01). Total uterine length was positively associated with only birth weights ( < 0.05). Mammary gland protein was negatively associated with preweaning growth ( < 0.01). Mammary gland fat was positively associated with birth weight and number of piglets weaned ( > 0.05). These results indicate that colostrum consumption, birth weights, preweaning growth rate, number weaned, and parity are associated with gilt development traits during later life.


Asunto(s)
Reproducción/fisiología , Maduración Sexual/fisiología , Porcinos/crecimiento & desarrollo , Animales , Peso al Nacer , Calostro , Dieta/veterinaria , Estro , Femenino , Paridad , Embarazo , Reproducción/genética , Maduración Sexual/genética , Porcinos/genética , Destete
6.
J Anim Sci ; 93(6): 2722-9, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26115260

RESUMEN

Colostrum affects gut and uterine gland development in the neonatal piglet, suggesting that subsequent growth and reproductive performance may be affected. Measuring immunoglobulin in piglet serum using the immunoglobulin immunocrit on Day 1 of age provides a simple, inexpensive indication of the amount of colostrum acquired by the piglet in the first day of life. Relationships between serum immunoglobulin immunocrit measures and subsequent growth rates, age at puberty, incidence of puberty failure, litter size, and lactation performance were examined in pigs born and subsequently farrowing between 2009 and 2013. Immunoglobulin immunocrit measures were collected on 16,762 piglets on Day 1 of age. Of these piglets, BW measurements were available from 15,324 (7,684 males and 7,640 females) piglets at a range of ages from weaning to 200 d of age, allowing an assessment of growth rates. Age at puberty was recorded from a subset of 2,857 of the females after observing them for estrous behavior from approximately 170 to 250 d of age. To examine relationships between d 1 immunocrit and puberty failure, gilts with immunocrit measures that failed to reach puberty (n = 119) were matched with littermate gilts with immunocrit measures that achieved puberty (n = 167). Similarly, number born alive was collected on a subset (n = 799) of females from first to fourth parities for which d 1 immunocrits were measured on them as neonates. Finally, d 1 immunocrit effect on adult lactational competence was assessed by measuring litter average (offspring of 440 females) and litter average piglet preweaning growth rate (offspring of 774 females) in females where d 1 immunocrits were available from them as neonates. Results indicated that low d 1 immunocrits were subsequently associated with reduced growth (P < 0.01), increased age at puberty (P < 0.01), reduced number born alive (P < 0.05), reduced litter average immunocrit (P < 0.05), and reduced litter average preweaning growth rate during lactation (P < 0.05). This suggests that management efforts to improve the amount of colostrum ingested by neonatal piglets would result in beneficial changes in production efficiency, particularly for gilts destined for the breeding herd. It also suggests that the immunoglobulin immunocrit can be useful in monitoring colostrum ingestion to maximize the beneficial effects of colostrum on subsequent performance.


Asunto(s)
Animales Recién Nacidos/sangre , Calostro/inmunología , Inmunoglobulinas/sangre , Sus scrofa/fisiología , Factores de Edad , Animales , Animales Recién Nacidos/inmunología , Peso Corporal/fisiología , Suplementos Dietéticos , Femenino , Lactancia/fisiología , Tamaño de la Camada/fisiología , Masculino , Pubertad/fisiología , Maduración Sexual/fisiología , Sus scrofa/sangre , Porcinos
7.
Free Radic Biol Med ; 87: 137-47, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25937176

RESUMEN

Diabetes-induced cardiac complications include left ventricular (LV) dysfunction and heart failure. We previously demonstrated that LV phosphoinositide 3-kinase p110α (PI3K) protects the heart against diabetic cardiomyopathy, associated with reduced NADPH oxidase expression and activity. Conversely, in dominant negative PI3K(p110α) transgenic mice (dnPI3K), reduced cardiac PI3K signaling exaggerated diabetes-induced cardiomyopathy, associated with upregulated NADPH oxidase. The goal was to examine whether chronic supplementation with the antioxidant coenzyme Q(10) (CoQ(10)) could attenuate LV superoxide and diabetic cardiomyopathy in a setting of impaired PI3K signaling. Diabetes was induced in 6-week-old nontransgenic and dnPI3K male mice via streptozotocin. After 4 weeks of diabetes, CoQ(10) supplementation commenced (10 mg/kg ip, 3 times/week, 8 weeks). At study end (12 weeks of diabetes), markers of LV function, cardiomyocyte hypertrophy, collagen deposition, NADPH oxidase, oxidative stress (3-nitrotyrosine), and concentrations of CoQ(9) and CoQ(10) were determined. LV NADPH oxidase (Nox2 gene expression and activity, and lucigenin-enhanced chemiluminescence), as well as oxidative stress, were increased by diabetes, exaggerated in diabetic dnPI3K mice, and attenuated by CoQ(10). Diabetes-induced LV diastolic dysfunction (prolonged deceleration time, elevated end-diastolic pressure, impaired E/A ratio), cardiomyocyte hypertrophy and fibrosis, expression of atrial natriuretic peptide, connective tissue growth factor, and ß-myosin heavy chain were all attenuated by CoQ(10). Chronic CoQ(10) supplementation attenuates aspects of diabetic cardiomyopathy, even in a setting of reduced cardiac PI3K protective signaling. Given that CoQ(10) supplementation has been suggested to have positive outcomes in heart failure patients, chronic CoQ(10) supplementation may be an attractive adjunct therapy for diabetic heart failure.


Asunto(s)
Fosfatidilinositol 3-Quinasa Clase I/biosíntesis , Cardiomiopatías Diabéticas/tratamiento farmacológico , Estrés Oxidativo/efectos de los fármacos , Ubiquinona/análogos & derivados , Disfunción Ventricular Izquierda/tratamiento farmacológico , Animales , Antioxidantes/administración & dosificación , Fosfatidilinositol 3-Quinasa Clase I/genética , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/genética , Cardiomiopatías Diabéticas/genética , Cardiomiopatías Diabéticas/patología , Modelos Animales de Enfermedad , Humanos , Masculino , Ratones , Ratones Transgénicos , NADPH Oxidasas/biosíntesis , NADPH Oxidasas/genética , Fosfatidilinositol 3-Quinasas/genética , Transducción de Señal/efectos de los fármacos , Ubiquinona/administración & dosificación , Ubiquinona/metabolismo , Disfunción Ventricular Izquierda/genética , Disfunción Ventricular Izquierda/patología
8.
J Anim Sci ; 92(6): 2422-32, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24867930

RESUMEN

Omega fatty acids and zinc contribute to physiological pathways that could affect the farrowing process, stillbirth, preweaning mortality, and postweaning return to estrus. To determine effects of omega fatty acids and zinc on these reproductive traits, gilts were mated and fed either a control diet, a diet supplemented with 1.09% Gromega, a diet supplemented with 0.07% zinc sulfate, or a diet supplemented with both Gromega and zinc sulfate from d 80 of gestation until farrowing. Farrowings were video recorded to obtain birth intervals for each piglet, and the number of live and stillborn piglets was recorded. On d 1 after farrowing, piglets were weighed, and the smallest piglet in each litter was sacrificed. A blood sample was collected to measure the immunoglobulin immunocrit ratio, and brain, cerebellum, brain stem, full and empty stomach (to calculate stomach content weight), and heart weights were recorded. Because myelination of specific brain regions may affect preweaning mortality, brain stem, cerebellum, and spinal cord tissues were measured for content of myelin basic proteins and myelin lipids. For remaining piglets, survival to weaning and weaning weights were recorded. Results indicated a weak positive correlation (r = 0.23, P < 0.05) between immunocrit values and brain stem high molecular weight myelin basic protein. There was also a Gromega × zinc supplementation interaction (P < 0.05) on brain stem high molecular weight myelin basic protein in which the combined treatment was greater than the control or each supplement alone. Zinc treatment decreased stillbirth rate during prolonged farrowing and subsequent preweaning survival of low birth weight piglets. Gromega increased overall stillbirth rate and increased the stillbirth rate during prolonged farrowing. There were no relationships between myelin measurements and preweaning survival. In conclusion, combined Gromega and zinc supplementation appeared to improve myelination, but zinc alone improved stillbirth and preweaning survival.


Asunto(s)
Animales Recién Nacidos , Suplementos Dietéticos , Ácidos Grasos Esenciales/farmacología , Mortinato/veterinaria , Porcinos/fisiología , Zinc/farmacología , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Peso Corporal , Encéfalo/fisiología , Dieta/veterinaria , Femenino , Fenómenos Fisiologicos Nutricionales Maternos , Embarazo
9.
Anim Genet ; 45(3): 340-9, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24779640

RESUMEN

Colostrum intake is critical to a piglet's survival and can be measured by precipitating out the γ-immunoglobulins from serum with ammonium sulfate (immunocrit). Genetic analysis of immunocrits on 5312 piglets indicated that the heritabilities (se) for direct and maternal effects were 0.13 (0.06) and 0.53 (0.08) respectively. To identify QTL for direct genetic effects, piglets with the highest and lowest immunocrits from 470 litters were selected. Six sets of DNA pools were created based on sire of the litter. These 12 DNA pools were applied to Illumina Porcine SNP60 BeadChips. Normalized X and Y values were analyzed. Three different SNP selection methods were used: deviation of the mean from high vs. low pools, the deviation adjusted for variance based on binomial theory and ANOVA. The 25 highest ranking SNPs were selected from each evaluation for further study along with 12 regions selected based on a five-SNP window approach. Selected SNPs were individually genotyped in the 988 piglets included in pools as well as in 524 piglets that had intermediate immunocrits. Association analyses were conducted fitting an animal model using the estimated genetic parameters. Nineteen SNPs were nominally associated (P < 0.01) with immunocrit values, of which nine remained significant (P < 0.05) after Bonferroni correction, located in 16 genomic regions on 13 chromosomes. In conclusion, the pooling strategy reduced the cost to scan the genome by more than 80% and identified genomic regions associated with a piglet's ability to acquire γ-immunoglobulin from colostrum. Each method to rank SNPs from the pooled analyses contributed unique validated markers, suggesting that multiple analyses will reveal more QTL than a single analysis.


Asunto(s)
Animales Recién Nacidos/genética , Animales Recién Nacidos/inmunología , Calostro/metabolismo , Inmunidad Materno-Adquirida/genética , Inmunoglobulina G/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos/veterinaria , Sitios de Carácter Cuantitativo , Sus scrofa/genética , Sus scrofa/inmunología , Animales , ADN/genética , Femenino , Genotipo , Masculino , Polimorfismo de Nucleótido Simple , Embarazo
10.
J Anim Sci ; 91(5): 2122-32, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23463559

RESUMEN

We hypothesized that creatine supplementation would reduce birth intervals, stillbirth rate, and preweaning survival in pigs because of its reported improvement of athletic performance in humans. In Exp. 1, gilts (n = 42) and first parity sows (n = 75) were mated at estrus. Beginning on d 110 of gestation, dams received either no treatment or 20 g creatine daily until farrowing. At farrowing in November 2008, pigs were monitored by video camera to determine individual piglet birth intervals. On d 1, piglets were weighed, euthanized, and the cerebellum, brain stem, and spinal cord were collected from the largest and smallest piglets in each litter to measure myelin basic proteins, myelin cholesterol, glucocerebrosides, phosphatidylethanolamine, phosphatidylcholine, and sphingomyelin. Preweaning mortality of the remaining piglets was recorded, including whether a piglet had been overlayed by the dam. A second experiment was performed using gilts (n = 90), farrowing in July 2010, to test differential effects of creatine supplementation during hot, humid weather when dams typically have more difficulty farrowing. Once again, gilts were provided either no supplementation or 20 g creatine daily from d 110 to the day of farrowing. Gilts were video recorded during farrowing, piglets were weighed on d 1, and preweaning mortality (including overlays) was recorded. In Exp. 1, creatine supplementation had no effect on birth intervals or stillbirth rate. Creatine supplementation improved the amount of myelin lipids in brain regions of piglets, particularly the brain stem. Creatine supplementation also reduced overlays of low birth weight piglets from gilts but not second parity sows. Data from Exp. 2 were combined with gilt data from Exp. 1 to examine the effect of creatine, season, and their interaction. There were no effects of treatment or season on birth intervals, stillbirth rates, or overall preweaning mortality. Creatine treatment reduced the incidence of overlays in low birth weight piglets in the combined data set. These results suggest that creatine supplementation improved myelination and may reduce the incidence of low birth weight piglets being crushed by the dam.


Asunto(s)
Creatina/metabolismo , Longevidad/efectos de los fármacos , Paridad/efectos de los fármacos , Mortinato/veterinaria , Enfermedades de los Porcinos/epidemiología , Porcinos/fisiología , Alimentación Animal/análisis , Animales , Creatina/administración & dosificación , Suplementos Dietéticos/análisis , Femenino , Embarazo , Mortinato/epidemiología , Enfermedades de los Porcinos/tratamiento farmacológico , Factores de Tiempo
11.
Biol Reprod ; 87(5): 126, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23018188

RESUMEN

Growth hormone (GH) is important in maternal adaptation to pregnancy, and maternal circulating GH concentrations are reduced in human growth-restricted pregnancies. In the pig, maternal GH treatment throughout early to mid pregnancy increases fetal growth, despite constraining effects of adolescent and primiparous pregnancy, high litter size, and restricted maternal nutrition. Because GH cannot cross the placenta and does not increase placental weight, we hypothesized that its effects on fetal growth might be via improved placental structure or function. We therefore investigated effects of maternal GH treatment in pigs on structural correlates of placental function and placental expression of nutrient transporters important to fetal growth. Multiparous (sows) and primiparous pregnant pigs (gilts) were treated with GH (~15 µg kg(-1) day(-1)) or vehicle from Days 25-50 of gestation (n = 7-8 per group, term ~115 days). Placentas were collected at Day 50 of gestation, and we measured structural correlates of function and expression of SLC2A1 (previously known as GLUT1) and SLC38A2 (previously known as SNAT2) nutrient transporters. Maternal GH treatment did not alter placental size or structure, increased protein expression of SLC2A1 in trophoblast (+35%; P = 0.037) and on its basal membrane (+44%; P = 0.011), and increased SLC38A2 protein expression in the basal (+44%; P = 0.001) but not the apical cytoplasm of trophoblast. Our findings suggest that maternal GH treatment increases fetal growth, in part, by enhancing placental nutrient transporter protein expression and hence fetal nutrient supply as well as trophoblast proliferation and differentiation and may have the potential to ameliorate intrauterine growth restriction.


Asunto(s)
Sistema de Transporte de Aminoácidos A/análisis , Desarrollo Fetal/efectos de los fármacos , Transportador de Glucosa de Tipo 1/análisis , Hormona del Crecimiento/administración & dosificación , Placenta/fisiología , Sus scrofa , Sistema de Transporte de Aminoácidos A/fisiología , Animales , Femenino , Desarrollo Fetal/fisiología , Peso Fetal/efectos de los fármacos , Edad Gestacional , Transportador de Glucosa de Tipo 1/fisiología , Inmunohistoquímica , Tamaño de los Órganos , Placenta/química , Placenta/efectos de los fármacos , Embarazo , Receptor IGF Tipo 1/análisis , Trofoblastos/química
12.
Mol Phylogenet Evol ; 62(1): 9-20, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22001302

RESUMEN

The phylogeny of Celastraceae tribe Euonymeae (≈ 230 species in eight genera in both the Old and New Worlds) was inferred using morphological characters together with plastid (matK, trnL-F) and nuclear (ITS and 26S rDNA) genes. Tribe Euonymeae has been defined as those genera of Celastraceae with generally opposite leaves, isomerous carpels, loculicidally dehiscent capsules, and arillate seeds (except Microtropis). Euonymus is the most diverse (129 species) and widely cultivated genus in the tribe. We infer that tribe Euonymeae consists of at least six separate lineages within Celastraceae and that a revised natural classification of the family is needed. Microtropis and Quetzalia are inferred to be distinct sister groups that together are sister to Zinowiewia. The endangered Monimopetalum chinense is an isolated and early derived lineage of Celastraceae that represents an important component of phylogenetic diversity within the family. Hedraianthera is sister to Brassiantha, and we describe a second species (Brassiantha hedraiantheroides A.J. Ford) that represents the first reported occurrence of this genus in Australia. Euonymus globularis, from eastern Australia, is sister to Menepetalum, which is endemic to New Caledonia, and we erect a new genus (Dinghoua R.H. Archer) for it. The Madagascan species of Euonymus are sister to Pleurostylia and recognized as a distinct genus (Astrocassine ined.). Glyptopetalum, Torralbasia, and Xylonymus are all closely related to Euonymus sensu stricto and are questionably distinct from it. Current intrageneric classifications of Euonymus are not completely natural and require revision.


Asunto(s)
Euonymus/clasificación , Genes de Plantas , Filogenia , Plastidios/genética , ADN Espaciador Ribosómico/genética , Euonymus/anatomía & histología , Euonymus/genética , Flores/anatomía & histología , Funciones de Verosimilitud , Hojas de la Planta/anatomía & histología , Polen/anatomía & histología , ARN Ribosómico/genética , Semillas/anatomía & histología , Alineación de Secuencia , Análisis de Secuencia de ADN
13.
J Neural Eng ; 4(4): 390-8, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18057506

RESUMEN

Though high-frequency alternating current (HFAC) can block nerve conduction, the block is invariably preceded by an onset response which is a period of repetitive nerve firing. We tested the hypothesis that slowly ramping up the amplitude of the HFAC waveform could produce block without this initial onset response. Computer simulations were performed, using the McIntyre-Richardson-Grill (MRG) model of myelinated mammalian axon. A ramped-amplitude HFAC was applied to axons of diameters ranging from 7.3 microm to 16 microm and at frequencies ranging from 3125 Hz to 40 kHz. The ramped-amplitude HFAC was also investigated in vivo in preparations of rat sciatic nerve. Sinusoidal voltage-regulated waveforms, at frequencies between 10 kHz and 30 kHz, were applied with initial amplitudes of 0 V, linearly increasing with time to 10 V. Ramp durations ranged from 0 s to 60 s. In both the MRG model simulations and the experiments, ramping the HFAC waveform did not eliminate the onset response. In the rat experiments, the peak amplitude of the onset response was lessened by ramping the amplitude, but both the onset response duration and the amount of onset activity as measured by the force-time integral were increased.


Asunto(s)
Potenciales de Acción/fisiología , Terapia por Estimulación Eléctrica/métodos , Estimulación Eléctrica/métodos , Modelos Neurológicos , Bloqueo Nervioso/métodos , Nervio Ciático/fisiología , Animales , Simulación por Computador , Ratas , Ratas Sprague-Dawley
14.
Child Care Health Dev ; 33(2): 206-12, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17291325

RESUMEN

OBJECTIVE: To evaluate the impact of a shared care approach in clinical management with a drug liaison midwife (DLM) service for mothers and infants established in 1995-1996 in an inner city area and to address the problem of congenital abnormality and microcephaly with fetal drug exposure. METHODS: Descriptive analysis of data in live births of women enrolled in a methadone maintenance programme in 1991-1994 (n = 78) and 1997-2001 (n = 98), including time spent in hospital, treatment for neonatal abstinence syndrome (NAS), admission to the neonatal medical unit (NMU) and follow-up for child health checks. RESULTS: In 1997-2001 compared with 1991-1994, the mothers used more methadone in the last week of pregnancy (median 40.0 mg/day vs. 21.5 mg/day, P = 0.0006) and there were more preterm deliveries (36% vs. 21%, P = 0.03). The infants spent less time in hospital (median 5 days vs. 28 days, P < 0.0001), a smaller proportion had treatment for NAS (14% vs. 79%, P < 0.0001), and NMU admission was reduced (median 14 days vs. 26 days, P < 0.0003). Neonatal convulsions (P = 0.0001) and jaundice (P < 0.001) occurred less frequently, and more infants were breastfed (P = 0.001). One infant in each study group had a cleft palate and none had microcephaly. Child health checks for 18-24 months showed a favourable outcome in 1997-2001. CONCLUSIONS: We altered antenatal care and modified neonatal management, subsequently infants spent less time in hospital and NMU admissions were reduced with less NAS treatment. Congenital abnormalities and microcephaly were not common and as regular child health checks were possible, the impact of the DLM service in shared management merits further investigation, for mother-infant bonding and developmental outcome.


Asunto(s)
Atención a la Salud/organización & administración , Cuidado del Lactante/normas , Servicios de Salud Materna/organización & administración , Metadona/efectos adversos , Partería/organización & administración , Narcóticos/efectos adversos , Femenino , Humanos , Recién Nacido , Relaciones Interprofesionales , Tiempo de Internación , Microcefalia/inducido químicamente , Microcefalia/epidemiología , Síndrome de Abstinencia Neonatal/epidemiología , Evaluación de Procesos y Resultados en Atención de Salud , Atención Dirigida al Paciente/organización & administración , Embarazo , Resultado del Embarazo , Efectos Tardíos de la Exposición Prenatal/inducido químicamente
15.
J Nutr Health Aging ; 10(2): 151-3, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16554952

RESUMEN

BACKGROUND: Seasonal Affective Disorder (SAD) is a sub-type of depression that only occurs during the winter months. A reduction in vitamin D may be linked to SAD. Since vitamin D deficiency has been reported to be common in older people, vitamin D supplementation may be expected to reduce seasonal mood disturbance in this group. OBJECTIVE: To assess the effect of vitamin D supplementation on the mental health of older women. SETTING: Primary care in three areas of the UK (Herts, Newcastle, York). SUBJECTS: Women aged 70 years or more recruited to the trial in the months May-October. INTERVENTION: Eligible women were randomised to receive calcium and vitamin D supplementation or no supplementation. OUTCOME MEASURE: At baseline and the six monthly assessment the mental component score (MCS), calculated from the SF-12 questionnaire was used to assess participants' subjective psychological well-being. RESULTS: A total of 2117 women recruited to the trial had their baseline measures taken between the months of May-October (1205 woman in the control group and 912 women in the intervention group). Of these women, 1621 had a MCS score at baseline and six months. Comparison of the six month mean MCS scores, adjusting for baseline MCS score and age, showed there was no significant difference between the two scores (p = 0.262). CONCLUSIONS: Supplementing elderly women with 800 IU of vitamin D daily did not lead to an improvement in mental health scores.


Asunto(s)
Salud Mental , Psicometría/métodos , Trastorno Afectivo Estacional/prevención & control , Vitamina D/administración & dosificación , Anciano , Calcio de la Dieta/administración & dosificación , Suplementos Dietéticos , Femenino , Humanos , Resultado del Tratamiento
16.
Br J Nutr ; 90(2): 283-93, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12908888

RESUMEN

Maternal nutrition and growth hormone (GH) treatment during early- to mid-pregnancy can each alter the subsequent growth and differentiation of muscle in progeny. We have investigated the effects of varying maternal nutrition and maternal treatment with porcine (p) GH during the second quarter of pregnancy in gilts on semitendinosus muscle cross-sectional area and fibre composition of progeny, and relationships between maternal and progeny measures and progeny muscularity. Fifty-three Large White x Landrace gilts, pregnant to Large White x Duroc boars, were fed either 2.2 kg (about 35 % ad libitum intake) or 3.0 kg commercial ration (13.5 MJ digestible energy, 150 g crude protein (N x 6.25)/kg DM)/d and injected with 0, 4 or 8 mg pGH/d from day 25 to 50 of pregnancy, then all were fed 2.2 kg/d for the remainder of pregnancy. The higher maternal feed allowance from day 25 to 50 of pregnancy increased the densities of total and secondary fibres and the secondary:primary fibre ratio in semitendinosus muscles of their female progeny at 61 d of age postnatally. The densities of secondary and total muscle fibres in semitendinosus muscles of progeny were predicted by maternal weight before treatment and maternal plasma insulin-like growth factor-II during treatment. Maternal pGH treatment from day 25 to day 50 of pregnancy did not alter fibre densities, but increased the cross-sectional area of the semitendinosus muscle; this may be partially explained by increased maternal plasma glucose. Thus, maternal nutrition and pGH treatment during the second quarter of pregnancy in pigs independently alter muscle characteristics in progeny.


Asunto(s)
Fenómenos Fisiológicos Nutricionales de los Animales , Hormona del Crecimiento/farmacología , Fenómenos Fisiologicos Nutricionales Maternos/fisiología , Músculo Esquelético/crecimiento & desarrollo , Preñez/fisiología , Porcinos/fisiología , Animales , Peso Corporal/fisiología , Femenino , Factor I del Crecimiento Similar a la Insulina/análisis , Intercambio Materno-Fetal/fisiología , Desarrollo de Músculos/fisiología , Fibras Musculares Esqueléticas/efectos de los fármacos , Músculo Esquelético/efectos de los fármacos , Fenotipo , Embarazo
17.
J R Soc Med ; 93(5): 254-7, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10884770

RESUMEN

The first 50 websites identified on searching the Internet for 'weight loss diets' were assessed systematically and their content compared with published clinical guidelines for management of obesity. The relevance and quality of the sites varied enormously. Only 3 confined themselves to sound dietary advice. Most promoted dietary supplements or other 'slimming aids', often of uncertain composition and based on dubious physiological principles. Potential hazards--for example, those of very low calorie diets--were rarely highlighted and certain regimens on offer were potentially dangerous.


Asunto(s)
Internet/normas , Obesidad/dietoterapia , Pérdida de Peso , Protocolos Clínicos , Dieta Reductora , Estudios de Evaluación como Asunto , Humanos
18.
J Agric Food Chem ; 48(2): 503-6, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10691665

RESUMEN

Six volatile compounds, ethylmethylbenzene (1), 1-isopentyl-2,4, 5-trimethylbenzene (2), 2-(hex-3-ene-2-one)phenylmethyl ketone (3), E and Z isomers of 3-butylidene-3H-isobenzofuran-1-one (4 and 5), and 2-penten-1-ylbenzoic acid (6), were isolated from the mosquitocidal hexane extract of Delphinium x cultorum cv. Magic Fountains flowers. In addition, the ethyl acetate extract, which displayed corn earworm antifeedant activity, yielded 4-hydroxybenzoic acid (7) and bis(4-hydroxyphenyl)methanol (8). However, compounds 7 and 8 were not biologically active.


Asunto(s)
Culicidae/efectos de los fármacos , Insecticidas/química , Magnoliopsida/química , Animales , Cromatografía de Gases y Espectrometría de Masas , Modelos Químicos , Mariposas Nocturnas/efectos de los fármacos
19.
Pain ; 75(2-3): 395-7, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9583777

RESUMEN

Neurogenic dysaesthetic pain in the neck following surgery for tumours in the neck is rare. Rarer still is the combination of pain following surgery with syncope. We looked at four patients who had tumours within the neck excised and then went on to develop neurogenic dysaesthetic neck pain associated with syncope. Distinction is made between neurogenic dysaesthetic pain following neck surgery and glossopharyngeal neuralgia which has been previously reported in association with neck surgery and also glossopharyngeal neuralgia with syncope. Spinal cord stimulation was used successfully to treat the dysaesthetic pain and syncope in three of the patients while the fourth patient died from the effects of his tumour. Medical practitioners may wish to consider spinal cord stimulation in relation to treating neurogenic dysaesthetic neck pain with syncope.


Asunto(s)
Neoplasias de Cabeza y Cuello/cirugía , Dolor de Cuello/etiología , Parestesia/etiología , Complicaciones Posoperatorias , Síncope/etiología , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dolor de Cuello/terapia , Parestesia/terapia , Médula Espinal/fisiopatología , Síncope/terapia , Estimulación Eléctrica Transcutánea del Nervio
20.
Br J Neurosurg ; 12(5): 402-8, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10070441

RESUMEN

Percutaneous spinal cord stimulation (SCS) (Medtronic model 3487A PISCES-Quad lead) was carried out in 10 patients with rest pain from advanced peripheral vascular disease of the lower limb, who were unsuitable for conventional treatment. Trial stimulation ranged from 1-20 weeks and was associated with pain relief in nine of the patients. Claudication distance was improved in six patients. Trophic lesions improved in one patient with small artery disease. Spinal cord stimulation did not reverse the course of acute gangrenous lesions. The distal arterial pressure measured by Doppler Ankle/Brachial Pressure Index, (ABPI), showed no change. The capillary blood flow and skin temperature of both feet, measured, respectively, by Laser Doppler flowmetry and skin thermistor, showed a tendency to decrease when the stimulation was at the higher level, above T10, compared with an increase when the stimulation was at the lower level T12. Transcutaneous oxygen tension monitoring of the symptomatic foot showed an increase in four out of five patients. Pain relief was not dependent on circulatory changes, but it was more significant when the circulatory changes showed an impressive increase in the blood flow. The mechanism of these circulatory changes is probably by modulation of the sympathetic nervous system. Recognition of the optimal sitting of SCS may be critical in the clinical use of this technique, which seems to be a valuable option in the treatment of patients with advanced peripheral vascular disease (PVD).


Asunto(s)
Arteriosclerosis/rehabilitación , Terapia por Estimulación Eléctrica/métodos , Claudicación Intermitente/rehabilitación , Isquemia/rehabilitación , Pierna/irrigación sanguínea , Anciano , Anciano de 80 o más Años , Arteriosclerosis/fisiopatología , Velocidad del Flujo Sanguíneo , Presión Sanguínea/fisiología , Capilares/fisiopatología , Femenino , Humanos , Claudicación Intermitente/fisiopatología , Isquemia/fisiopatología , Masculino , Persona de Mediana Edad , Dolor/rehabilitación , Médula Espinal , Resultado del Tratamiento
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