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1.
Rev Sci Instrum ; 95(1)2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38230994

RESUMEN

A method for determining the fast-ion population density in magnetically confined plasmas as a function of pitch-radius, (λ, R), using a solid-state neutral-particle analyzer (ssNPA) signal and neutral-beam injection (NBI) power-output data has been developed. Oscillations in the NBI power output are replicated only in the active part of the ssNPA signal, allowing this to be separated from the passive and background signals, which usually complicate data from this diagnostic. Results obtained using this method are compared with those from standard techniques using data from the Mega-Amp Spherical Tokamak Upgrade spherical tokamak.

2.
Phys Rev Lett ; 126(3): 032503, 2021 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-33543956

RESUMEN

A nuclear spectroscopy experiment was conducted to study α-decay chains stemming from isotopes of flerovium (element Z=114). An upgraded TASISpec decay station was placed behind the gas-filled separator TASCA at the GSI Helmholtzzentrum für Schwerionenforschung in Darmstadt, Germany. The fusion-evaporation reactions ^{48}Ca+^{242}Pu and ^{48}Ca+^{244}Pu provided a total of 32 flerovium-candidate decay chains, of which two and eleven were firmly assigned to ^{286}Fl and ^{288}Fl, respectively. A prompt coincidence between a 9.60(1)-MeV α particle event and a 0.36(1)-MeV conversion electron marked the first observation of an excited state in an even-even isotope of the heaviest man-made elements, namely ^{282}Cn. Spectroscopy of ^{288}Fl decay chains fixed Q_{α}=10.06(1) MeV. In one case, a Q_{α}=9.46(1)-MeV decay from ^{284}Cn into ^{280}Ds was observed, with ^{280}Ds fissioning after only 518 µs. The impact of these findings, aggregated with existing data on decay chains of ^{286,288}Fl, on the size of an anticipated shell gap at proton number Z=114 is discussed in light of predictions from two beyond-mean-field calculations, which take into account triaxial deformation.

3.
Neurol Neuroimmunol Neuroinflamm ; 2(2): e65, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25635261

RESUMEN

OBJECTIVE: To assess the relationship between CD56(bright) natural killer (NK) cells and multiple sclerosis (MS) disease activity in patients with relapsing-remitting MS treated with daclizumab high-yield process (DAC HYP). METHODS: Data were from patients enrolled in a 52-week randomized, double-blind, placebo-controlled study of DAC HYP and its extension study. Assessments included relationships of CD56(bright) NK cell numbers (identified using fluorescence-activated cell sorting) at weeks 4 and 8 with the numbers of new or newly enlarging T2-hyperintense lesions between weeks 24 and 52 and the annualized relapse rate. RESULTS: In DAC HYP-treated patients but not placebo-treated patients, the numbers of CD56(bright) NK cells increased over 52 weeks of treatment, and their numbers at weeks 4 and 8 predicted the number of new or newly enlarging T2-hyperintense lesions between weeks 24 and 52 of treatment (p ≤ 0.005 for each comparison). Similar but nonsignificant trends were observed between CD56(bright) NK cell counts and the annualized relapse rate in DAC HYP-treated patients. DAC HYP-treated patients who showed lower levels of expansion of CD56(bright) NK cells still developed fewer new or newly enlarging T2-hyperintense lesions than placebo-treated patients during the first year of treatment. CONCLUSIONS: CD56(bright) NK cells appear to mediate some of the treatment-related effects of DAC HYP, but their numbers do not account for the full effect of DAC HYP on MS-related outcomes.

4.
Phys Rev Lett ; 109(1): 012501, 2012 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-23031099

RESUMEN

The rotational band structure of the Z=104 nucleus (256)Rf has been observed up to a tentative spin of 20ℏ using state-of-the-art γ-ray spectroscopic techniques. This represents the first such measurement in a superheavy nucleus whose stability is entirely derived from the shell-correction energy. The observed rotational properties are compared to those of neighboring nuclei and it is shown that the kinematic and dynamic moments of inertia are sensitive to the underlying single-particle shell structure and the specific location of high-j orbitals. The moments of inertia therefore provide a sensitive test of shell structure and pairing in superheavy nuclei which is essential to ensure the validity of contemporary nuclear models in this mass region. The data obtained show that there is no deformed shell gap at Z=104, which is predicted in a number of current self-consistent mean-field models.

5.
Phys Rev Lett ; 104(25): 252701, 2010 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-20867370

RESUMEN

The fusion-evaporation reaction 244Pu(48Ca,3-4n){288,289}114 was studied at the new gas-filled recoil separator TASCA. Thirteen correlated decay chains were observed and assigned to the production and decay of {288,289}114. At a compound nucleus excitation energy of E{*}=39.8-43.9 MeV, the 4n evaporation channel cross section was 9.8{-3.1}{+3.9} pb. At E^{*}=36.1-39.5 MeV, that of the 3n evaporation channel was 8.0{-4.5}{+7.4} pb. In one of the 3n evaporation channel decay chains, a previously unobserved α branch in 281Ds was observed (probability to be of random origin from background: 0.1%). This α decay populated the new nucleus 277Hs, which decayed by spontaneous fission after a lifetime of 4.5 ms.

6.
Phys Rev Lett ; 102(21): 212501, 2009 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-19519098

RESUMEN

The rotational band structure of 255Lr has been investigated using advanced in-beam gamma-ray spectroscopic techniques. To date, 255Lr is the heaviest nucleus to be studied in this manner. One rotational band has been unambiguously observed and strong evidence for a second rotational structure was found. The structures are tentatively assigned to be based on the 1/2-[521] and 7/2-[514] Nilsson states, consistent with assignments from recently obtained alpha decay data. The experimental rotational band dynamic moment of inertia is used to test self-consistent mean-field calculations using the Skyrme SLy4 interaction and a density-dependent pairing force.

7.
Arch Virol ; 150(9): 1885-902, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15824886

RESUMEN

An adult mouse model for studies of latency and recurrence after vaginal HSV-2 infection is not available at present, largely because the infection kills most mice within 14 days. We describe here an antiviral therapy that rescues most vaginally infected mice from death. Vaginally infected mice were nearly all rescued by combined treatment with one dose of monoclonal anti-HSV glycoprotein D 3 days after infection plus valacyclovir in the drinking water on days 3, 4, 5, 7, 9, 11, 13, and 15 after infection. At 60 days after infection, PCR measurements revealed that most rescued mice had viral DNA in their lumbosacral dorsal root ganglia, lumbosacral spinal cords, and paracervical autonomic ganglia, consistent with the possibility that latent infections were established. At this time, immunolabeling revealed CD45+ lymphoid cells in these neural tissues in rescued mice but not in normal control mice. In vivo depletion of T lymphocytes with monoclonal antibodies caused a recurrence of herpes illness symptoms earlier and in a larger proportion of rescued mice than was observed in non-depleted rescued mice. Interestingly, many rescued mice (46/114) spontaneously developed a syndrome of typical herpes illness symptoms that began with ruffled fur on a mouse that previously had sleek fur and progressed to arched backs, feeble gait, hindlimb paralysis, and death or euthanasia, or in some cases to recovery to health. This high incidence of apparent spontaneous recurrence of HSV-2 infection in rescued mice suggests that it may be possible, with some refinement of the procedure, to obtain an effective adult mouse model for studies of therapeutic vaccination to inhibit or prevent HSV-2 recurrence after genital tract infection.


Asunto(s)
Aciclovir/análogos & derivados , Anticuerpos Antivirales/uso terapéutico , Antivirales/uso terapéutico , Herpes Genital/tratamiento farmacológico , Herpes Genital/patología , Herpesvirus Humano 2 , Valina/análogos & derivados , Aciclovir/uso terapéutico , Administración Oral , Animales , Anticuerpos Monoclonales/uso terapéutico , Modelos Animales de Enfermedad , Quimioterapia Combinada , Femenino , Herpes Genital/inmunología , Herpes Genital/virología , Herpesvirus Humano 2/inmunología , Herpesvirus Humano 2/aislamiento & purificación , Inyecciones Intraperitoneales , Ratones , Ratones Endogámicos BALB C , Prevención Secundaria , Valaciclovir , Valina/uso terapéutico , Proteínas del Envoltorio Viral/inmunología , Latencia del Virus
8.
J Anim Sci ; 83(2): 449-54, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15644518

RESUMEN

The effects of the proportion of pigs removed from an established group and subsequent floor space on growth performance during the final 19 d of the finishing period were evaluated using 28 pens of mixed-sex crossbred pigs (mean initial BW = 113.4 +/- 0.57 kg; n = 1,456; approximately 52 pigs per pen). A randomized block design was used with four pig-removal treatments: 1) 0% of pigs removed [Control], 2) approximately 25% of pigs removed, 3) approximately 50% of pigs removed, and 4) approximately 50% of pigs removed and floor and feeder spaces/pig decreased to equal those of Control. A block consisted of four pens with the same number of pigs and sex ratio per pen and with similar initial BW. Pens within blocks were randomly allocated to treatment, and the heaviest animals were removed from Treatments 2, 3, and 4 at the start of the study. Group size and floor space/pig for Treatments 1, 2, 3, and 4 were 52 and 0.65 m(2), 39 and 0.87 m(2), 26 and 1.30 m(2), and 26 and 0.65 m(2), respectively. Each pen contained a six-place feeder that provided 212 cm of total trough space; however, only three-places were accessible to pigs on Treatment 4. Compared with Controls, removing 25 or 50% of pigs resulted in increased (P < 0.001) ADG by 20.6 and 21.0%, ADFI by 10.8 and 7.9%, and G:F by 7.7 and 14.3%, respectively. Average daily gain by pigs on Treatment 4 (50% removal rate and decreased floor and feeder spaces) was greater (P < 0.05) than that of the Controls, but lower (P < 0.05) than that of Treatment 3 pigs (50% removal rate, no adjustment in floor or feeder spaces). No differences were observed among treatments for either morbidity or mortality. These results indicate that removing 25 or 50% of the heaviest pigs from groups of finishing pigs increased growth rate of the remaining pigs, and that the improved performance was only partly due to increased floor and feeder spaces.


Asunto(s)
Crianza de Animales Domésticos/métodos , Vivienda para Animales , Porcinos/crecimiento & desarrollo , Tejido Adiposo/diagnóstico por imagen , Tejido Adiposo/fisiología , Animales , Composición Corporal , Peso Corporal/fisiología , Femenino , Pisos y Cubiertas de Piso , Análisis de los Mínimos Cuadrados , Masculino , Músculo Esquelético/diagnóstico por imagen , Músculo Esquelético/fisiología , Densidad de Población , Distribución Aleatoria , Ultrasonografía , Aumento de Peso
9.
Neurogastroenterol Motil ; 16(1): 61-74, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14764206

RESUMEN

Fas ligand (FasL) is involved in the pathogenesis of inflammatory diseases and immune privilege. We examined the expression of FasL in the enteric nervous system (ENS) in murine colitis and guinea-pig ileitis. We studied FasL immunoreactivity, functional integrity of the ENS, severity of colitis, and distribution of neutrophils in wild type and B6/gld mice that lack functional FasL. In ileitis, the distribution of FasL, CD4+ and CD8+ T cells was examined. FasL expression was increased in the ENS of wild type mice with colitis, but decreased labelling of nerve fibres was noted in B6/gld mice. Neutrophils were more abundant and widely distributed in B6/gld mice. Colitis was more severe and persistent in B6/gld mice 7 days after induction. Functional parameters of intestinal secretion and motility in B6/gld mice were the same as controls. In ileitis, FasL expression was increased in the guinea-pig ENS and returned to control levels following the resolution of inflammation. While T cells were not present in the ENS of controls, they were observed during inflammation, but were excluded from ganglia. The number of enteric neurons was unchanged over the course of inflammation. The expression of FasL is altered in intestinal inflammation and contributes to its resolution in experimental colitis.


Asunto(s)
Inflamación/metabolismo , Intestinos/fisiología , Glicoproteínas de Membrana/biosíntesis , Plexo Mientérico/metabolismo , Animales , Western Blotting , Colitis/inducido químicamente , Colitis/inmunología , Colitis/metabolismo , Modelos Animales de Enfermedad , Proteína Ligando Fas , Tránsito Gastrointestinal/fisiología , Cobayas , Ileítis/inducido químicamente , Ileítis/inmunología , Ileítis/metabolismo , Inmunohistoquímica , Inflamación/inmunología , Intestinos/fisiopatología , Masculino , Ratones , Ratones Transgénicos , Plexo Mientérico/inmunología , Neutrófilos/inmunología , Ácido Trinitrobencenosulfónico/toxicidad
10.
J Anim Sci ; 81(4): 836-42, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12723070

RESUMEN

The effect of reduced pig growth rate postweaning as a result of restricted floor space and feeder trough space on subsequent growth to slaughter was investigated in a wean-to-finish system. Crossbred pigs (n = 1,728) were used in a randomized block design with a 2 x 2 x 2 factorial arrangement of treatments: 1) floor space (high [0.630 m2/pig] vs. low floor space [0.315 m2/pig]), 2) feeder trough space (unrestricted [4 cm/pig] vs. restricted feeder trough space [2 cm/pig]), and 3) period of imposing floor- and feeder-trough-space treatments (12 vs. 14 wk postweaning). Growth performance was measured from weaning (5.5 +/- 0.01 kg of BW; 17 d of age) to slaughter (the end of wk 25 postweaning). From the end of the treatment period to the end of wk 25, pigs on all treatments had the same floor and feeder trough space. Pigs with low floor space had lower (P < 0.01) ADG, ADFI, and gain:feed ratio than those with high floor space, and were therefore lighter (P < 0.05) at the end of the postweaning treatment period. Pigs given the restricted feeder trough space had lower (P < 0.05) ADFI, similar (P > 0.05) ADG, and higher (P < 0.01) gain:feed ratio than those with unrestricted feeder trough space during the treatment period. Pigs in the 14-wk treatment period had higher (P < 0.01) ADG and ADFI, but lower gain:feed than those in the 12-wk treatment during that period. In the subsequent period, from the end of treatment to wk 25, there was an interaction (P < 0.05) between floor space and treatment period; the difference in ADG and gain:feed for pigs on low vs. high floor space was greater for the 14-wk than the 12-wk treatment period. However, low-floor-space pigs tended (P = 0.06) to be lighter than high-floor-space pigs at the end of wk 25 postweaning. Neither feeder trough space nor treatment period affected pig growth performance during the period from the end of treatment to wk 25. Carcass backfat and longissimus depths at the end of wk 25 were not influenced (P > 0.05) by treatment. In summary, pigs with restricted growth due to low floor space until either 12 or 14 wk postweaning had increased growth and feed efficiency in the subsequent period to wk 25 postweaning, with only a slight effect on BW and no effect on carcass measures.


Asunto(s)
Crianza de Animales Domésticos/métodos , Composición Corporal , Ingestión de Alimentos , Vivienda para Animales , Porcinos/crecimiento & desarrollo , Tejido Adiposo/anatomía & histología , Tejido Adiposo/crecimiento & desarrollo , Animales , Peso Corporal , Femenino , Pisos y Cubiertas de Piso , Masculino , Distribución Aleatoria , Destete
11.
J Anim Sci ; 81(2): 353-9, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12643477

RESUMEN

The objective was to evaluate the effect of restricted early postweaning growth rate due to diet complexity, pen space, or both on subsequent growth to market in a wean-to-finish system. Pigs (n = 1,728) were used in a randomized block design with a 2 x 2 factorial arrangement of treatments: 1) diet complexity (Complex vs Simple) and 2) space allocation (Unrestricted vs Restricted). Treatments were imposed for the first 8 wk after weaning (period 1) and growth was measured from weaning (5.0 +/- 0.01 kg body weight; 15 d of age) to the end of wk 23 postweaning. The Simple diet was based on corn-soybean meal with minimal inclusion of milk products, processed cereals, and animal protein-based ingredients compared to the Complex diet. Floor and feeder-trough spaces were 0.63 m2 and 4 cm and 0.21 m2 and 2 cm per pig for Unrestricted and Restricted space treatments, respectively. From the end of wk 8 to end of wk 23 (period 2), pigs on all treatments had the same floor and feeder spaces and were fed common diets. There was no interaction (P > 0.05) between diet and space treatments. In period 1, Simple diets resulted in similar average daily feed intake (ADFI; 639 vs 650 +/- 5.4 g; P > 0.05), but lower average daily gain (ADG; 408 vs 424 +/- 3.8 g; P < 0.01) and gain:feed ratio (0.64 vs 0.65 +/- 0.002; P < 0.001), and lighter body weight (2.8%; P < 0.01) compared to the Complex diets. In period 2, growth was not affected (P > 0.05) by previous diet complexity, and pig body weight was similar (114.4 vs 114.4 +/- 0.37 kg, P > 0.05) at the end of wk 23. In period 1, pigs with Restricted space had lower ADG (398 vs 434 +/- 3.8 g; P < 0.001), ADFI (621 vs 668 +/- 5.4 g; P < 0.001), and gain:feed ratio (0.64 vs 0.65 +/- 0.002; P < 0.01), and were lighter at the end of wk 8 (6.5%; P < 0.001) than those with Unrestricted space. However, in period 2, pigs with Restricted space had higher (P < 0.01) ADG (3%), ADFI (2%), and gain:feed ratio (3%) than those with Unrestricted space, and body weight was similar (114.5 vs 114.3 +/- 0.37 kg; P > 0.05) at end of wk 23. Carcass backfat and loin-eye depth at market body weight were influenced by neither diet nor space treatment. Using a simple diet program and restricted space allowance immediately postweaning resulted in a lower early growth rate, but had no impact on pig body weight or carcass measures at market.


Asunto(s)
Alimentación Animal , Crianza de Animales Domésticos/métodos , Vivienda para Animales , Porcinos/crecimiento & desarrollo , Animales , Ingestión de Alimentos/fisiología , Femenino , Masculino , Densidad de Población , Distribución Aleatoria , Destete , Aumento de Peso
12.
J Anim Sci ; 80(9): 2241-6, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12350000

RESUMEN

Two studies were carried out with the same group of pigs within a wean-to-finish system. In Study 1 (weaning to wk 8 postweaning), the effect of feeder-trough space in pens that were double-stocked on pig growth was evaluated. In Study 2 (end of wk 8 to 112 +/- 1.5 kg BW), the effect of variation in pig BW within a pen on growth was investigated. In Study 1, a randomized block design was used to compare two feeder-trough space treatments (Double [4 cm/pig] vs Control [2 cm/pig]). Pigs (n = 1,728) were randomly allocated at weaning (5.4 +/- 0.01 kg BW; 16 d of age) to mixed-sex pens (8 pens/treatment) of 108 pigs/pen on the basis of BW. Floor-space (0.30 m2/pig) and drinker allocation (13 pigs/drinker) were the same for both treatments. Two six-place (35 cm/place) feeders were positioned together in the center of each pen and were accessible from both sides. For the Double treatment, both feeders contained feed, whereas for the Control only one feeder contained feed. In Study 2, a randomized block design was used to compare three BW/variation in BW treatments: 1) Heavy BW/Low variation, 2) Light BW/Low variation, and 3) Mixed BW/Normal variation. The double-stocked pens of pigs from within previous feeder-trough space treatment were split into two groups of 54 pigs (equal sex ratio) having either high or low BW variation within pen. Pigs had free access to feed and water throughout the studies. In Study 1, doubling feeder-trough space did not affect (P > 0.05) pig growth from weaning to the end of wk 6. From wk 6 to 8, pigs on the Double treatment compared to the Control treatment had higher (P < 0.05) ADG and were heavier (P < 0.05), but had similar (P > 0.05) ADFI and gain:feed ratio. In Study 2, pen-BW treatment did not impact (P > 0.05) ADG or gain:feed ratio; however, Heavy/Low had greater (P < 0.01) ADFI than Light/Low with Mixed/Normal being intermediate for ADFI. At 112 kg BW, CV of BW within a pen was similar (P > 0.05) across treatments; however, days to market BW was greater (P < 0.001) for Light/Low than Heavy/ Low with Mixed/Normal being intermediate. In summary, increasing feeder-trough space from 2 to 4 cm per pig increased daily gain after wk 6 postweaning in double-stocked pens of pigs; however, sorting pigs on the basis of BW when splitting pens did not impact growth rate or variation in BW within a pen at market BW.


Asunto(s)
Crianza de Animales Domésticos/métodos , Ingestión de Alimentos/fisiología , Vivienda para Animales , Porcinos/crecimiento & desarrollo , Crianza de Animales Domésticos/instrumentación , Animales , Composición Corporal , Peso Corporal/fisiología , Femenino , Masculino , Densidad de Población , Distribución Aleatoria , Destete , Aumento de Peso
13.
J Anim Sci ; 80(6): 1442-50, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12078723

RESUMEN

Two studies were carried out in different wean-to-finish barns to determine the effects of double stocking on pig growth performance. In Study 1, pigs (n = 1,560) were used in a randomized complete block design with a 2 x 2 factorial arrangement of treatments: initial stocking treatment (Single [52 pigs/pen] vs Double [104 pigs/pen] stocked for 10 wk after weaning) and weighing frequency (High [12 times during the study] vs Low [3 times]) on pig performance from weaning (5.9+/-0.01 kg BW; 17 d of age) to harvest (114+/-0.67 kg BW). Floor and feeder space per pig were 0.650 m2 and 4 cm and 0.325 m2 and 2 cm for the single- and double-stocked treatments, respectively. In Study 2, pigs (n = 1,458) were used in a randomized complete block design to evaluate two initial stocking treatments (Single [27 pigs] vs Double [54 pigs] stocked for 10 wk after weaning) on pig performance from weaning (4.8+/-0.01 kg BW; 15 d of age) to harvest (24 wk after weaning). Floor and feeder space per pig were 0.640 m2 and 3.4 cm and 0.320 m2 and 1.7 cm for single- and double-stocked pens, respectively. In both studies, double-stocked pigs were split at the end of wk 10 into two equal-sized groups of similar mean BW and CV of BW, and one group was moved to a different pen in the same building. In Study 1, performance was not affected (P > 0.10) by frequency of weighing. For the first 10 wk after weaning, the Double compared to the Single treatment had lower ADG (7.7 and 7.9%, for Studies 1 and 2, respectively; P < 0.001) and lighter pigs at wk 10 (6.8 and 7.3%, respectively; P < 0.001). During the first 10 wk in Study 1, Double compared to the Single pigs had lower ADFI (7%; P < 0.001) but similar gain:feed (P > 0.10). From wk 11 to harvest, pigs on Double and Single treatments had similar (P > 0.10) ADG in both studies and, in Study 1, ADFI was unaffected by initial stocking treatment, but double-stocked pigs had greater gain:feed (4%, P < 0.01). Double-stocked pigs required an additional 2 d to reach a fixed harvest BW (P < 0.05) in Study 1 and were lighter (4%; P < 0.05) at 24 wk after weaning in Study 2. Carcass measures were similar (P > 0.10) for double- and single-stocked pigs. Double-stocked pigs that were moved at the end of 10 wk had growth performance similar (P > 0.10) to those that remained in the original pen. In summary, double stocking reduced growth rate to 10 wk after weaning but subsequently had no effect on growth rate and improved feed efficiency.


Asunto(s)
Crianza de Animales Domésticos/métodos , Vivienda para Animales , Porcinos/crecimiento & desarrollo , Animales , Composición Corporal/fisiología , Femenino , Masculino , Densidad de Población , Distribución Aleatoria , Destete , Aumento de Peso
14.
J Anim Sci ; 79(5): 1067-73, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11374526

RESUMEN

Crossbred pigs (n = 1,400) were used to evaluate the effect of group size (25 vs 50 vs 100 pigs/pen) in a wean-to-finish production system on growth performance and carcass measures. Pigs were weaned at 17 d (range = 15 to 19) of age with a mean initial BW of 5.9 +/- 0.02 kg and taken to a final mean pen weight of 116 +/- 0.9 kg. A 10-phase dietary regimen was used, and pigs had free access to feed and water. Feeder-trough space (4.3 cm/pig) and floor-area allowance (0.68 m2/pig) were the same for all group sizes. Compared to groups of 25, pigs in groups of 50 and 100 animals were lighter (P < 0.001) at the end of wk 8 after weaning and had lower (3%, P < 0.01) ADG and gain:feed (G/F) but similar (P > 0.05) ADFI during the first 8 wk of the study. At the end of the study, pig weight and the coefficient of variation in pig weight within a pen were similar (P > 0.05) across group sizes. During the period from 8 wk after weaning to the end of the study, pigs in groups of 100 compared to 50 animals had greater (3%, P < 0.01) ADG, and pigs in groups of 25 were intermediate for ADG. Average daily feed intake during this period was similar (P > 0.05) for all group sizes; however, G/F was greater (3%, P < 0.01) for groups of 100 compared to 25 or 50 animals. For the overall study period, ADG, ADFI, and G/F from weaning to slaughter weight were similar across group sizes (P > 0.05; 655, 648, and 658 g; 1,759, 1,755, and 1,759 g; and 0.37, 0.37, and 0.37; for ADG, ADFI, and G/F, respectively, for groups of 25, 50, and 100 pigs, respectively). Mortality was similar (P > 0.05) across group sizes; however, morbidity (pigs removed due to poor health or injury) was higher in groups of 25 pigs compared to the other two group sizes (7.0, 3.5, and 3.9% for groups of 25, 50, and 100, respectively; P < 0.05). Group-size treatment did not affect (P > 0.05) carcass dressing percentage, backfat thickness, or loin-eye depth. In summary, growth performance from weaning to market weight was not affected by group size.


Asunto(s)
Crianza de Animales Domésticos/métodos , Vivienda para Animales , Porcinos/crecimiento & desarrollo , Destete , Animales , Composición Corporal , Peso Corporal , Femenino , Masculino , Distribución Aleatoria
16.
J Anim Sci ; 78(11): 2784-9, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11063299

RESUMEN

Crossbred pigs weaned at 17 d of age (n = 1,760; mean initial BW = 5.6 +/- 0.7 kg) were used in two 4-wk trials (four replicates per trial) to evaluate the effects of three pen designs on pig performance. The designs were 1) large group size (100 pigs/pen) with five two-sided feeders in a single, central location in the pen; 2) large group size (100 pigs/pen) with five two-sided feeders in multiple (five) locations in the pen; and 3) small group size (20 pigs/pen) with a single two-sided feeder in a central location in the pen. Each feeder provided two 20.3-cm-wide feeding places on each side. Pigs had free access to feed and water. Feeder-trough space (4 cm/pig) and floor-area allowance (0.17 m2/pig) were the same for all treatments. Pigs in the large-group treatments were lighter (15.6 and 15.6 vs 16.0 kg; P < 0.01) at the end of wk 4 and had lower ADG (358 and 357 vs 373 g; P < 0.01) and ADFI (510 and 521 vs 544 g; P < 0.01) during wk 2 through 4 than pigs in small groups. Gain:feed ratio was similar (P > 0.05) for all treatment groups throughout the study. For large groups, feed disappearance from each of the five feeders was similar (P > 0.05) for both multiple- and single-location treatments. In summary, large group size reduced pig growth performance, but the approach to providing multiple feeding locations that was employed in this experiment did not increase feed intake or growth performance of pigs in the large groups.


Asunto(s)
Alimentación Animal , Crianza de Animales Domésticos/métodos , Porcinos/crecimiento & desarrollo , Destete , Crianza de Animales Domésticos/instrumentación , Animales , Peso Corporal , Clima , Femenino , Vivienda para Animales , Masculino
17.
Immunology ; 101(1): 126-31, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11012763

RESUMEN

We investigated the involvement of antibody in protection against vaginal herpes simplex virus type-2 (HSV-2) infection by comparing intact and B-cell knockout (KO) mice. Vaginal immunization of intact mice with attenuated HSV-2 markedly reduced an HSV-2 challenge infection in the vagina. In contrast, immunization of B-cell KO mice produced less immunity against the challenge infection and that immunity occurred in a different pattern. At 20 hr after challenge, immunostaining of virus proteins in the vaginal epithelium and shed virus protein titres in the vaginal secretions were not significantly different between immunized and non-immunized B-cell KO mice and were much greater than in immunized intact mice. At 48 hr after challenge, the vaginal infection in immunized B-cell KO mice was markedly less than at 20 hr but remained approximately sevenfold higher than in intact mice. This pattern of challenge infection in the vagina indicates that B cells, and probably the antibody derived from them, provided significant protection against reinfection in intact mice, especially during the first 20 hr after challenge, while other effector mechanisms became important between 20 and 48 hr after challenge. To determine whether T-cell immunity in immunized B-cell KO mice was equal to that in intact mice, we assessed interferon-gamma (IFN-gamma) secretion by memory T cells in vivo in the vagina at 20 hr after challenge. We found no significant differences in the up-regulation of major histocompatibility complex (MHC) class II antigens in the epithelium, up-regulation of vascular cell adhesion molecule-1 (VCAM-1) in vascular endothelium, or recruitment of T cells to the mucosa, indicating that the memory T-cell response to virus challenge was the same in intact and B-cell KO mice.


Asunto(s)
Linfocitos B/inmunología , Herpes Genital/inmunología , Enfermedades Vaginales/inmunología , Animales , Femenino , Herpes Genital/prevención & control , Inmunidad Celular , Inmunoglobulina A Secretora/análisis , Inmunoglobulina G/análisis , Interferón gamma/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Subgrupos de Linfocitos T/inmunología , Vagina/inmunología , Enfermedades Vaginales/prevención & control , Vacunas Virales/inmunología
18.
J Anim Sci ; 78(8): 2062-7, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10947088

RESUMEN

Crossbred weanling piglets (n = 1,920; mean initial BW, 5.3 +/- .7 kg) were used in two 9-wk trials employing a randomized block design in a 2 x 2 factorial arrangement of treatments to determine effects of group size (20 [Small = S] or 100 [Large = L] pigs/pen) and floor-space allowance (calculated requirement [CR] or calculated requirement less 50% of estimated "free space" [CR-50]) on growth performance. Free space was estimated for each group size. From wk 1 through 4 after weaning, S and L groups at CR were allowed a floor space of .17 m2/pig, and at CR-50, S and L groups were allowed .15 m2/pig and .13 m2/pig, respectively. From wk 5 through 9 after weaning, all CR treatment pigs were provided a floor space of .38 m2/pig, and for the CR-50 treatment, S and L pigs were allowed .32 m2/pig and .28 m2/pig, respectively. Piglets had free access to feed and water. Feeder-trough space per pig was the same for both group sizes. Feed-intake data were collected for only wk 1 through 4. Group size by floor-space allowance interactions (P < .05) were found for gain/feed ratio (G/F) for wk 1 and wk 2 through 4, but not for wk 1 through 4. Piglets in L groups were lighter (P < .001) at the end of wk 1, 4, and 9 by 2, 4, and 5%, respectively, and had lower ADG (6%; P < .001) throughout the trial than S piglets. During wk 1 through 4, feed intake was lower (7%, P < .001) in L piglets than in S piglets, but G/F was similar (P > .05). Piglets in CR groups had greater ADG (5%; P < .01) throughout the trial, with a greater G/F (P < .05) for wk 1 through 4, and were heavier (P < .01) than those in CR-50 groups at the end of wk 4 (3%) and 9 (4%). Pigs in L groups had a greater within-pen coefficient of variation in BW at the end of wk 9 than pigs in S groups. Large groups and reduced floor-space allowance reduced piglet growth performance in the nursery.


Asunto(s)
Vivienda para Animales , Porcinos/crecimiento & desarrollo , Animales , Distribución Aleatoria , Destete
19.
Surgery ; 127(6): 634-40, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10840358

RESUMEN

BACKGROUND: The increased popularity of pancreas transplants has led to an increased number of potential candidates for retransplants after the initial graft has been lost to technical failure or rejection. We studied a group of recipients who underwent pancreas transplants at a single center to determine whether retransplant recipients were at higher risk of complications. METHODS: Between June 1, 1994, and Dec 31, 1997, a total of 213 pancreas transplants were performed at the University of Minnesota. Of these, 187 were primary transplants and 26 were retransplants. Demographically, the two groups were not significantly different. We analyzed and compared the two groups with respect to incidence of surgical complications, graft survival rates, and patient survival rates. RESULTS: Surgical complications such as bleeding and vascular thrombosis were slightly more common after retransplants, but this trend did not quite reach statistical significance. Infectious complications and leaks were equivalent between the two groups. The incidence of acute rejection was higher after retransplants (P =.02). At 3 years posttransplant, patient survival was no different between the two groups, but pancreas graft survival was lower after retransplants (P =.08). The incidence of early graft loss (by 6 months posttransplant) was significantly higher in retransplant recipients (27% vs 14%, P =.04). CONCLUSIONS: Pancreas retransplants can be performed with a minimal increase in surgical complications. However, graft survival after retransplants is slightly inferior to that after primary transplants, probably for both immunologic and nonimmunologic reasons. Retransplants can be offered to suitable candidates, but they may require more aggressive monitoring for rejection.


Asunto(s)
Trasplante de Páncreas/efectos adversos , Adulto , Rechazo de Injerto/etiología , Supervivencia de Injerto , Humanos , Trasplante de Páncreas/mortalidad , Complicaciones Posoperatorias/etiología , Reoperación , Factores de Riesgo , Tasa de Supervivencia , Resultado del Tratamiento
20.
Hybridoma ; 19(2): 161-5, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10868796

RESUMEN

Nine monoclonal antibodies (MAbs) against human and rodent ING1 protein have been generated using an IL6-secreting mouse myeloma line. These antibodies are all effective in recognizing ING1 protein in ELISAs, Western blot assays, and by indirect immunofluorescence. Combining different CAb monoclonal antibodies in a Western blot assay also allows detection of the very low levels of endogenous ING1 found in fibroblast cells in culture and the identification of at least two isoforms of ING1 in normal human diploid fibroblasts and established brain cancer cell lines.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Proteínas/inmunología , Animales , Anticuerpos Monoclonales/química , Western Blotting , Proteínas de Ciclo Celular , Proteínas de Unión al ADN , Ensayo de Inmunoadsorción Enzimática , Fibroblastos/citología , Técnica del Anticuerpo Fluorescente Indirecta , Genes Supresores de Tumor , Humanos , Isotipos de Inmunoglobulinas , Proteína Inhibidora del Crecimiento 1 , Péptidos y Proteínas de Señalización Intracelular , Ratones , Ratones Endogámicos BALB C , Proteínas Nucleares , Isoformas de Proteínas/inmunología , Transfección , Células Tumorales Cultivadas , Proteínas Supresoras de Tumor
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