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1.
Appl Radiat Isot ; 211: 111405, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38917620

RESUMO

The preparation of nanometer-thick molybdenum-99 (99Mo) sources using the droplet deposition method was investigated. The quality of these prepared sources was analyzed using scanning electron microscopy (SEM), electron Rutherford backscattering (ERBS) techniques, and Geant4 simulations. The emitted electrons resulting from the ß--decay of the prepared 99Mo sources, with energies below 2.2 keV, were measured and compared with existing literature data as well as the results obtained from our in-house Monte-Carlo model, BrIccEmis.

2.
J Anim Sci ; 89(6): 1787-94, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21606444

RESUMO

Sows subjected to prenatal stress have been found to produce offspring that have altered responses to stress. Our objective was to determine if exposing a sow to stress would alter the response of the offspring to lipopolysaccharide (LPS) at 2 mo of age or their response to mixing stress at 4 mo of age. Sow treatments consisted of intravenous injections of ACTH (1 IU/kg of BW), exposure to rough handling for a 10-min duration (rough), or no treatment (control) once per week from d 42 to 77 of gestation. At 2 mo of age, pigs from each treatment, 1 per litter (n = 21, 17, and 15 for the ACTH, rough, and control treatments, respectively), were challenged with 2 µg of LPS/kg of BW or saline, or served as a noninjected control. Their behavioral response to a human approach test and salivary cortisol were measured. At 4 mo of age, 1 pig from each treatment (n = 14, 14, and 15 for the ACTH, rough, and control treatments, respectively) was taken from its home pen and placed in a pen of unfamiliar pigs. At this time, a punch biopsy wound (6 × 6 mm) was created to measure the ability of the pig to heal the wound. At this same time, each pig received a 1-mL intramuscular injection of 20% ovine red blood cells (oRBC), and then a second injection of oRBC at 21 d postmixing. Blood samples were collected 3 times per week for 2 wk and then once a week for 4 more weeks. Blood samples were analyzed for cortisol, porcine corticosteroid-binding globulin, antibody response to oRBC, and nitric oxide production by macrophages. Behavior was recorded during the first 5 d after mixing. All pigs in the LPS challenge responded with characteristic sickness behavior; however, pigs in the rough treatment showed less sickness behavior than those in the other 2 treatments (P < 0.05). Maternal stress treatment did not affect (P < 0.43) salivary cortisol. Pigs from all treatments responded similarly to mixing stress with regard to cortisol, porcine corticosteroid-binding globulin, antibody titers, nitric oxide production, and hematology measures, and all pigs experienced the same amount of aggression in response to mixing. Without altering peripheral measures of stress responsivity, prenatal stress enhanced the ability of pigs to cope with a simulated immune challenge, which could prove to be an adaptation to challenging environments.


Assuntos
Hormônio Adrenocorticotrópico/farmacologia , Lipopolissacarídeos/toxicidade , Efeitos Tardios da Exposição Pré-Natal/veterinária , Estresse Fisiológico/fisiologia , Suínos/fisiologia , Animais , Feminino , Manobra Psicológica , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Estresse Fisiológico/efeitos dos fármacos
3.
J Anim Sci ; 87(10): 3218-25, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19542501

RESUMO

The synthetic met-enkephalin syndyphalin-33 (SD-33) increases feed intake in sheep and transiently increases circulating GH concentrations in sheep, rats, and pigs. Two experiments were performed to evaluate the effects of SD-33 on recently weaned pigs. In a preliminary experiment, pigs were administered SD-33 (0.5 micromol/kg, given intramuscularly) or saline immediately before a 3-h transport and subsequent placement into group pens. Treatment with SD-33 increased (P = 0.01) daily feed intake; cumulatively, pen intake over 7 d postweaning tended (P = 0.06) to be greater than in control pens. In Exp. 2, pigs were weaned and fitted with jugular catheters. The following day, pigs were treated with SD-33 or saline as described above. Transient increases (P < 0.05) in circulating concentrations of GH (at 1 and 1.5 h postinjection) and cortisol (at 3.5 and 4 h postinjection) were observed in pigs treated with SD-33 relative to controls. No difference in feed intake was observed between treatments over 4 d postinjection. Increased (P < 0.05) numbers of circulating neutrophils, lymphocytes, and monocytes were observed in both treatment groups over 4 d postinjection, and treatment with SD-33 tended (P = 0.07) to selectively increase monocyte numbers. Although SD-33 has potential to be used to increase feed intake and decrease the negative effects of stress during weaning in pigs, further investigation is needed to better understand the timing of effect and to rule out possible immunosuppressive effects.


Assuntos
Analgésicos Opioides/farmacologia , Ingestão de Alimentos/imunologia , Oligopeptídeos/farmacologia , Estresse Fisiológico/imunologia , Suínos/imunologia , Animais , Feminino , Hormônio do Crescimento/sangue , Hidrocortisona/sangue , Análise dos Mínimos Quadrados , Contagem de Leucócitos/veterinária , Masculino , Oligopeptídeos/administração & dosagem , Distribuição Aleatória
4.
J Anim Sci ; 86(11): 2913-9, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18599664

RESUMO

To examine the effects of exogenous porcine (p) ST on measures of stress and immune function in weaned pigs with or without transport, pigs (20 +/- 1 d of age) received daily injections of pST (0.5 mg/kg; n = 16) or saline (n = 16) for 5 d. On d 5, a blood sample was collected immediately before injection. At 4 h postinjection, pigs were weighed, sampled for blood, injected with di-nitrophenyl-conjugated keyhole limpet hemocyanin, and weaned. One half of the pigs in each group were transported for 3 h before placement in the nursery. Pigs were weighed, and blood was collected on 1, 7, and 14 d postweaning. Statistical significance was set at P < 0.05. Serum IGF-I concentrations were increased by pST and decreased by weaning, but not affected by transport. The free cortisol index was elevated in all pigs 1 d postweaning, although less in transported versus nontransported pigs. By 7 d postweaning, the free cortisol index returned to prewean values. Serum concentrations of immunoglobulin (Ig) G increased in all pigs by 14 d postweaning, but were not affected by pST or transport. Serum IgM concentrations were elevated at 7 and 14 d postweaning. Before weaning and again 1 d postweaning, pigs treated with pST had greater concentrations of IgM than did control animals. Circulating neutrophils increased in pST-treated pigs 4 h after the final pST injection. Improved immune function in weaned pigs by pST may lead to greater health and growth in a commercial setting.


Assuntos
Hormônio do Crescimento/farmacologia , Manobra Psicológica , Sistema Imunitário/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Suínos/fisiologia , Meios de Transporte , Animais , Peso Corporal/efeitos dos fármacos , Feminino , Hormônio do Crescimento/administração & dosagem , Hidrocortisona/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Leucócitos/efeitos dos fármacos , Masculino , Distribuição Aleatória , Suínos/imunologia , Transcortina/metabolismo , Desmame
5.
J Anim Sci ; 86(6): 1316-24, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18272847

RESUMO

Exposing a pregnant sow to stress has been shown to affect the resulting offspring. Our objective was to determine if rough handling of pregnant sows altered the physiology of her offspring and if these alterations were different from an experimentally induced model of prenatal stress. Sow treatments consisted of i.v. injections of ACTH (1 IU/kg of BW), exposure to rough handling for 10 min (Rough), or no treatment (Control) once a week during d 42 to 77 of gestation. To determine the plasma cortisol response to treatments, blood (5 mL) was collected from 30 sows after treatment administration. To conduct the prenatal stress study, a separate group of 56 sows was used in 1 of 4 replicates. At birth, production data were collected for each litter, including birth weight, number born, anogenital distance, and pig viability. At weaning, pigs were blocked by BW and sex, and placed in a nursery pen of 6 pigs, with 2 pigs from each treatment group. To assess the effect of treatments on cortisol, corticosteroid-binding globulin (CBG), and hematological cell profiles, blood was collected every other day for 10 d after weaning. Application of treatments caused plasma cortisol concentrations to be greatest in ACTH sows compared with Control sows (P < 0.001), with Rough sows having intermediate values (P = 0.07). Treatments did not affect the number of pigs born, number of stillborn, or pig viability (P > 0.40). The ratio of cortisol to CBG did not differ between treatments (P = 0.09). Hematological variables did not differ between treatments (P > 0.19). Pigs born to ACTH sows had a smaller anogenital distance compared with controls (P < 0.03), with pigs from Rough sows being intermediate. Our data indicate that swine exposed to prenatal stress (ACTH injection) can have alterations in sexual morphology without effects on growth or the immune cell populations measured in this study.


Assuntos
Hormônio Adrenocorticotrópico/farmacologia , Manobra Psicológica , Estresse Psicológico , Suínos/fisiologia , Desmame , Hormônio Adrenocorticotrópico/sangue , Animais , Animais Recém-Nascidos , Peso ao Nascer , Feminino , Hidrocortisona/sangue , Tamanho da Ninhada de Vivíparos , Gravidez , Complicações na Gravidez/sangue , Complicações na Gravidez/psicologia , Complicações na Gravidez/veterinária , Resultado da Gravidez , Efeitos Tardios da Exposição Pré-Natal , Distribuição Aleatória , Suínos/anatomia & histologia , Suínos/sangue , Suínos/psicologia
6.
Stress ; 10(3): 305-10, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17613944

RESUMO

The objective of this study was to document changes in plasma concentrations of total cortisol, porcine corticosteroid-binding globulin (pCBG), and the free cortisol index (FCI) in pigs over a 6-h period in response to adrenal stimulation or suppression. Twenty-four 8-week old pigs allotted in equal numbers were administered ACTH, dexamethasone or saline, and blood samples were collected every 15 min via an indwelling jugular catheter for 1 h prior to and 5 h following treatment. Total plasma cortisol increased in ACTH-treated pigs and decreased in dexamethasone-treated pigs within 0.25 and 0.5 h, respectively. In contrast, pCBG concentration was altered in an inverse fashion subsequent to the changes exhibited in total cortisol. FCI reflected the changes observed in total cortisol. These results further document the negative relationship that exists between circulating concentrations of plasma cortisol and pCBG, and illustrate that this association exists under conditions of acute stress in the pig.


Assuntos
Glândulas Suprarrenais/metabolismo , Hormônio Adrenocorticotrópico/metabolismo , Dexametasona/metabolismo , Hidrocortisona/sangue , Transcortina/metabolismo , Animais , Feminino , Estresse Fisiológico/sangue , Estresse Fisiológico/metabolismo , Suínos , Fatores de Tempo
7.
J Anim Sci ; 84(5): 1271-8, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16612032

RESUMO

The objective of this study was to determine the effects of castration on short-term growth performance, hormone profiles, and behavior in pigs at 3, 6, 9, or 12 d of age. Ninety intact male pigs were assigned randomly to a treatment age by litter [3, 6, 9, or 12 d of age; n = 9 to 13 pigs per treatment (age) group]. Pigs within a single litter were then assigned to noncastrated (NC) or castrated (CAS) treatment groups according to BW. Pigs were nonsurgically fitted with jugular catheters, and blood samples were drawn immediately before castration (0 h) and at 0.5, 1, 1.5, 2, 24, and 48 h after castration. Body weights were obtained when pigs were catheterized and again at 24 and 48 h after castration. Serum samples were analyzed for cortisol, porcine corticosteroid-binding globulin, and dehydroepiandrosterone sulfate (DHEA-S). No differences were detected in initial BW of pigs, and there was no overall treatment effect on growth performance of pigs at 24 or 48 h posttreatment. A time x treatment interaction was detected (P < 0.01) for serum cortisol concentrations, such that cortisol was greater in CAS pigs than in NC pigs. No overall effect of age at castration was observed on cortisol concentrations. At 24 h after castration, serum cortisol concentrations returned to baseline in all treatment groups; however, at 48 h after castration, overall cortisol concentrations were elevated (P < 0.01) in the 6-, 9-, and 12-d-old pigs in both the CAS and NC groups compared with baseline concentrations. Total cortisol and porcine corticosteroid-binding globulin were used to calculate the free cortisol index (FCI). A time x treatment interaction was observed (P < 0.01) for FCI, such that FCI was greater in CAS males than in NC males. The FCI was also affected by age (P < 0.01). There was a time x treatment x age interaction (P < 0.01) for serum DHEA-S, such that DHEA-S concentrations decreased in CAS animals but increased in NC animals, and DHEA-S concentrations increased with age. During the first 2 h after castration, there was an overall age effect (P = 0.01) on the time that pigs spent standing, such that 3-d-old pigs stood more than 6-, 9-, or 12-d-old pigs. Treatment did not influence the time that pigs spent nursing, lying, standing, or sitting, although there was a trend (P = 0.08) for CAS pigs to be less active than NC pigs. These data indicate that castration is stressful regardless of age; however, the stress associated with handling seems to increase as pigs age.


Assuntos
Envelhecimento/sangue , Envelhecimento/fisiologia , Hormônios/sangue , Orquiectomia/veterinária , Suínos/sangue , Suínos/crescimento & desenvolvimento , Animais , Comportamento Animal , Sulfato de Desidroepiandrosterona/sangue , Hidrocortisona/sangue , Masculino , Fatores de Tempo , Transcortina/metabolismo
8.
J Anim Sci ; 83(1): 208-15, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15583061

RESUMO

Plasma cortisol, porcine corticosteroid-binding globulin (pCBG), hepatic CBG expression, and other physiological and behavioral measures of stress were studied in pigs in response to elevated temperature in conjunction with establishing a social hierarchy. Twenty-four crossbred pigs were weaned at 25 d of age (three or six pigs from six sows) and housed in littermate groups at 23 +/- 2 degrees C. At 57 d of age (d 0), animals were weighed and placed under general anesthesia for collection of blood (10 mL) and liver (approximately 100 mg) samples. On d 1, three unacquainted pigs of similar BW (23 +/- 1 kg) from different litters were allotted to each of eight nursery pens within two environmentally controlled rooms (12 pigs per room). From d 1 to 7, one room was maintained at 23 +/- 2 degrees C (CON) and the other at 33 +/- 2 degrees C (HEAT). Both rooms were kept at 23 +/- 2 degrees C from d 8 to 14. Animals were videotaped for 72 h beginning on d 1 and 8 to document behavioral changes in response to room temperature. The social hierarchy of pigs within each pen was based on fight activity recorded on d 1 to 3. Blood and liver tissue were collected again on d 7 and 14. The ADG for HEAT pigs increased (P < 0.05) over d 8 to 14 compared with d 1 to 7. In contrast to CON pigs, HEAT pigs displayed increased (P < 0.01) drinking but decreased feeding and lying in contact with other pigs from d 1 to 3, and similar drinking and feeding but increased (P < 0.01) lying with contact behaviors from d 8 to 10. With the exception of subordinate pigs exhibiting less (P < 0.05) frequent standing/walking behavior than the dominant or intermediate pigs on d 1 to 3, frequency of behaviors for both recorded time periods did not differ among pigs due to social status, regardless of treatment. The concentration of plasma haptoglobin in HEAT pigs on d 7 compared with d 0 increased (467 vs. 763 mg/L; P < 0.05), whereas cortisol and pCBG decreased (274 vs. 235 nmol/L and 11.4 vs. 9.9 mg/L, respectively; P < 0.05) as a result of treatment. The free cortisol index (total cortisol/pCBG) was greater (P < 0.05) in HEAT pigs on d 14 than on d 0 or 7. Hepatic CBG mRNA level was not affected by treatment. On d 14, HEAT pigs had plasma cortisol, pCBG, and haptoglobin concentrations similar to those of CON pigs. These results indicate that measured behavioral and physiological responses were not related to social status, and decreased circulating levels of cortisol and pCBG in pigs following a 7-d exposure to elevated temperature may not be determined by hepatic CBG mRNA expression.


Assuntos
Comportamento Animal/fisiologia , Temperatura Alta , Estresse Fisiológico/veterinária , Suínos/fisiologia , Transcortina/fisiologia , Agressão/fisiologia , Animais , Análise Química do Sangue/veterinária , Peso Corporal/fisiologia , Aglomeração , Haptoglobinas/análise , Hidrocortisona/sangue , Fígado/química , RNA Mensageiro/análise , RNA Mensageiro/biossíntese , RNA Mensageiro/fisiologia , Estresse Fisiológico/etiologia , Estresse Fisiológico/fisiopatologia , Fatores de Tempo , Transcortina/análise , Transcortina/biossíntese , Aumento de Peso/fisiologia
9.
Domest Anim Endocrinol ; 24(4): 323-39, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12742550

RESUMO

The objectives of this study were to develop an assay for the direct measure of porcine corticosteroid-binding globulin (pCBG) and to confirm age-related changes in plasma pCBG concentration. Isolation and purification of pCBG from plasma was performed by affinity chromatography and HPLC-DEAE anion exchange techniques. Analysis by SDS-PAGE revealed two polypeptides (54 and 59 kDa) having similar amino acid homology (>50%) to previously reported sequences of seven mammalian species for the first 33 amino acids. Porcine CBG (20 ng/well) was immobilized to microtiter plates and standards or samples added along with rabbit antiserum developed against the purified pCBG. Goat anti-rabbit IgG-alkaline phosphatase conjugate was added followed by p-NPP substrate. The resultant color development was read at 405 nm. Intra- and interassay coefficients of variation (n=26) of a pooled sample were 10 and 15%, respectively. Age-related changes (P<0.001) in plasma pCBG concentration (n=203) from day 3 through 168 of age confirmed that, in the pig, changes seen in the percent distribution of cortisol among protein bound and free forms around day 28 of age are associated with an increase in CBG concentration.


Assuntos
Envelhecimento , Ensaio de Imunoadsorção Enzimática , Suínos/sangue , Transcortina/análise , Sequência de Aminoácidos , Animais , Cromatografia de Afinidade , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Eletroforese em Gel de Poliacrilamida , Feminino , Humanos , Masculino , Dados de Sequência Molecular , Homologia de Sequência , Transcortina/química
10.
Domest Anim Endocrinol ; 24(4): 341-51, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12742551

RESUMO

The objective of the present study was to evaluate the potential immunological benefit of adding menhaden fish oil to the diet of weaned pigs. Twenty-four crossbred male pigs were weaned at approximately 18 days of age and placed on a complex nursery diet containing 30% lactose and 7% plasma protein with 6% corn oil as the fat source (Cont, n=12) or with 5% menhaden fish oil and 1% corn oil as the fat source (MFO, n=12) for a period of 15 days. Body weights did not differ (P>0.78) between dietary groups either at the beginning or end of the 15 days feeding period. On day 15, all pigs were non-surgically fitted with an indwelling jugular catheter. On d 16, pigs received an i.v. injection of either saline (n=6/dietary group) or lipopolysaccharide (LPS; 150 microg/kg body weight; n=6/dietary group) and blood samples were collected at 30 min intervals for a period of 5h. Serum was harvested and stored at -80 degrees C for analysis of cortisol (CS), corticosteroid-binding globulin (CBG), tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma). There was no significant effect of diet on basal concentrations (Time 0) of any of the blood parameters analyzed. A Time x Treatment x Diet interaction (P<0.03) was observed for serum CS such that those pigs which consumed the MFO diet followed by LPS treatment had a reduced CS response as compared to the LPS-treated pigs on the Cont diet. A Time x Treatment interaction (P<0.01) was observed for serum CBG such that LPS treatment reduced circulating CBG as compared to the saline-treated pigs. Time x Treatment x Diet interactions were also observed for serum concentrations of TNF-alpha (P=0.084) and IFN-gamma (P=0.022) such that both the TNF-alpha and IFN-gamma response to the LPS challenge was lower in those pigs receiving the MFO diet as compared to the LPS-treated pigs on the Cont diet. Overall, serum CS was negatively correlated with the CBG response (r=-0.40, P<0.001), however, the strongest negative correlation was observed in the LPS-treated pigs which consumed the MFO diet (r=-0.63, P<0.001). While further studies are needed to evaluate the immunological response of including MFO in the nursery pig diet, the present study demonstrates that supplementation with MFO does indeed alter the immunological response to an LPS challenge.


Assuntos
Dieta , Gorduras Insaturadas na Dieta/administração & dosagem , Óleos de Peixe/administração & dosagem , Lipopolissacarídeos/administração & dosagem , Suínos/imunologia , Animais , Proteínas Sanguíneas/administração & dosagem , Peso Corporal , Óleo de Milho , Escherichia coli , Hidrocortisona/sangue , Interferon gama/sangue , Cinética , Lactose/administração & dosagem , Plasma , Suínos/crescimento & desenvolvimento , Transcortina/análise , Fator de Necrose Tumoral alfa/análise , Desmame
11.
J Anim Sci ; 80(2): 338-45, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11881923

RESUMO

One hundred twenty 8-wk-old barrows (20.3 +/- 2.0 kg BW) were used to examine the effect of split marketing on selected behavioral, physiological and performance parameters. Pigs were assigned by weight in a randomized complete block design to one of three treatments: SM (split-marketed), six pigs/pen (1.83 m2/pig); C (control), six pigs/pen (1.83 m2/pig); or MC (modified control), three pigs/pen (3.66 m2/pig). The heaviest half of SM animals were removed 1 wk prior to marketing penmates. Control and MC animals remained in their respective groups until marketing. Animals were videotaped during the first 72 h of the study (INITIAL), 72 h prior to (PRE), and following the removal (POST) of pigs in the SM treatment to quantify maintenance behaviors and to identify socially dominant, intermediate, and submissive pigs. A blood sample was collected from each animal upon completion of INITIAL, PRE, and POST time periods to determine neutrophil:lymphocyte ratio and plasma haptoglobin, cortisol, and corticosteroid-binding globulin (CBG) levels. Animals were weighed and feed disappearance was calculated biweekly. Tenth-rib backfat and area of the longissimus muscle at marketing were ultrasonically evaluated on all animals. Regardless of treatment, animals were more (P < 0.01) active (eating, standing/walking, fighting) at INITIAL than at PRE or POST times. Frequency and duration of fights per pen were less (P < 0.01) in MC than in C or SM pigs for all periods observed. Neutrophil:lymphocyte ratio, plasma haptoglobin, and CBG levels were greater (P < 0.01) during the INITIAL period than during the PRE or POST periods but did not differ between treatments. No treatment or time differences were detected in plasma cortisol levels. The MC pigs exhibited greater (P < 0.01) ADFI with poorer feed efficiency compared to C or SM pigs up to split marketing. During the POST period, both MC and SM pigs had greater (P < 0.01) ADFI with poorer (P < 0.01) feed efficiency than C pigs. The ADG was not different among animals as a result of treatment. There were no treatment differences for any of the carcass measurements. Significant differences in performance between the treatment groups could not be attributed to any physiological or behavioral measures reported here.


Assuntos
Criação de Animais Domésticos/métodos , Comportamento Animal/fisiologia , Abrigo para Animais , Estresse Fisiológico/veterinária , Suínos/fisiologia , Tecido Adiposo , Animais , Composição Corporal/fisiologia , Peso Corporal , Ingestão de Energia , Masculino , Músculo Esquelético/diagnóstico por imagem , Distribuição Aleatória , Estresse Fisiológico/sangue , Suínos/sangue , Suínos/crescimento & desenvolvimento , Ultrassonografia , Gravação em Vídeo
12.
J Dairy Sci ; 84(3): 641-8, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11286418

RESUMO

Transport of retinol (vitamin A alcohol) from retinoid stores in the liver to target tissues is accomplished exclusively by a specific plasma protein, retinol-binding protein. Within individuals, retinol-binding protein concentrations in plasma are regulated and remain constant except in extremes of vitamin A nutriture or in disease. In the present study, retinol-binding protein concentrations in plasma from preruminant calves supplemented with 0, 1700 (i.e., current NRC requirement), 34,000, or 68,000 IU of vitamin A daily from birth to 27 d of age (n = 6/treatment) were quantified. Retinol-binding protein concentrations at birth averaged 21 microg/ml (n = 24) or approximately 50% of concentrations in dairy heifers and cows. Plasma retinol and retinol-binding protein concentrations were correlated positively, corroborating the role of vitamin A nutriture in the regulation of retinol-binding protein secretion from the liver. In this regard, dietary vitamin A influenced positively retinol and retinol-binding protein concentrations and, as a consequence, the degree of saturation of retinol-binding protein with retinol. At 27 d of age, calves fed > or = 34,000 IU of vitamin A had substantially higher retinol and retinol-binding protein concentrations than did calves fed < or = 1700 IU of vitamin A, indicating that dietary vitamin A effects positively vitamin A status. The data also suggest that the current NRC requirement may not be sufficient to assure vitamin A adequacy in preruminant calves. Percent saturation of retionol-binding protein with retinol in all calves was < 35%, much lower than anticipated and suggests that the retinol requirement of vitamin A-responsive tissues exceeded vitamin A availability.


Assuntos
Animais Recém-Nascidos/metabolismo , Fígado/metabolismo , Proteínas de Ligação ao Retinol/metabolismo , Vitamina A/administração & dosagem , Vitamina A/sangue , Fatores Etários , Animais , Bovinos , Feminino , Necessidades Nutricionais , Proteínas Plasmáticas de Ligação ao Retinol , Vitamina A/metabolismo
13.
Biol Reprod ; 58(1): 240-7, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9472947

RESUMO

Studies were conducted to determine whether the corticosteroids cortisol and aldosterone, and corticosteroid-binding globulin (CBG) were present in the porcine early-embryonic environment. Cortisol was measured in uterine flushings from white crossbred gilts at Days 7, 10, 13, and 16 of the estrous cycle and pregnancy. Total content of cortisol increased (p < 0.01) between Days 13 and 16, and immunoreactive CBG (ir-CBG) increased (p < 0.01) between Days 10 and 13, in both cyclic and pregnant gilts. In a separate study with Chinese Meishan gilts, total cortisol and aldosterone content of uterine flushings increased (p < 0.02) between Days 10 and 15 of the estrous cycle and pregnancy. In another study with white crossbred gilts, CBG-like binding activity in uterine flushings was low at Day 10, then increased over 100-fold at Day 15 (p < 0.01). However, levels of CBG-like binding activity on Day 15 were 100-fold lower than those of ir-CBG measured in the previous study and could bind less than 4% of the uterine luminal cortisol. Differences between ir-CBG and CBG binding might be due to the ability of the CBG antibody to recognize either biologically inactive CBG or structurally similar molecules. CBG-like binding activity, which appeared unrelated to glucocorticoid receptors, was also present in the endometrial cytosol of white crossbred gilts. Concentrations (fmol/mg protein) of endometrial CBG-like activity decreased (p = 0.03) between Days 10 and 15 of the estrous cycle and pregnancy, did not differ with reproductive status, and on Day 15 were comparable to concentrations in uterine flushings but threefold lower (p < 0.01) than those in the serum. Equilibrium dissociation constants for CBG-like binding activities were comparable among the three locations. These studies indicate that corticosteroids are present-primarily in the free form-within the porcine uterine lumen and could influence early porcine conceptus development. Endometrial CBG-like binding activity could mediate actions of cortisol or progesterone on uterine function.


Assuntos
Corticosteroides/metabolismo , Estro/metabolismo , Prenhez/metabolismo , Suínos/metabolismo , Transcortina/metabolismo , Útero/metabolismo , Aldosterona/sangue , Aldosterona/metabolismo , Animais , Ligação Competitiva , Citosol/metabolismo , Dexametasona/sangue , Dexametasona/metabolismo , Endométrio/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Hidrocortisona/sangue , Hidrocortisona/metabolismo , Gravidez , Progesterona/metabolismo , Especificidade da Espécie , Fatores de Tempo
14.
Dis Colon Rectum ; 40(4): 500-3, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9106704

RESUMO

The first case of adenocarcinoma developing in a continent ileostomy is reported. A healthy, 39-year-old man with a continent ileostomy for 17 years developed subacute obstructive symptoms and was found on endoscopy to have a large adenocarcinoma involving the intussusception valve. At operation, he was found to have a large tumor originating in the valve, extending through the reservoir, and involving the afferent ileal limb. A number of metastatic lymph nodes were identified in the mesentery of the small bowel. He underwent excision of the pouch and formation of an end ileostomy. He is currently undergoing adjuvant chemotherapy. Biochemical and morphologic changes in the ileal pouch, both in the pelvis and the continent ileostomy, are discussed. The implications of this apparent de novo cancer arising in an ileal pouch are discussed.


Assuntos
Adenocarcinoma/etiologia , Neoplasias do Íleo/etiologia , Valva Ileocecal , Proctocolectomia Restauradora/efeitos adversos , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Adulto , Aneuploidia , Colite Ulcerativa/cirurgia , DNA de Neoplasias/análise , Citometria de Fluxo , Humanos , Neoplasias do Íleo/patologia , Neoplasias do Íleo/cirurgia , Masculino , Índice Mitótico
15.
Biol Reprod ; 57(6): 1445-50, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9408253

RESUMO

Retinol-binding protein (RBP) mRNA was localized to luminal and glandular epithelial cells of bovine endometrium by in situ hybridization. Relative levels of endometrial RBP mRNA expression during the estrous cycle and early pregnancy were determined by quantitative slot blot analysis and contrasted with uterine luminal concentrations of RBP. Expression of mRNA was moderate at Day 1 after estrus, declined at Day 5, reached lowest levels by Day 10, rose significantly through Days 15-17, and peaked at Day 20. RBP mRNA expression in pregnant animals was similar to that in cyclic animals on Day 15, doubled between Days 17 and 20, remained constant through Day 22, and rose slightly thereafter. Luminal RBP concentrations of cyclic cows, as determined by ELISA, decreased from Day 1 through Day 10, rose dramatically on Day 15, then declined through Day 20. Concentrations of RBP in uterine flushes from pregnant animals were similar to those of cyclic cows on Day 15 but remained relatively constant through Day 17. It is concluded that 1) RBP synthesis occurs in the luminal and glandular epithelial cells, 2) RBP transcription and secretion are correlated with each other, and 3) ovarian steroids, possibly in conjunction with uterine concentrations of their receptors, modulate uterine RBP expression.


Assuntos
Bovinos/metabolismo , Endométrio/metabolismo , Estro/fisiologia , Prenhez/fisiologia , RNA Mensageiro/análise , Proteínas de Ligação ao Retinol/metabolismo , Animais , Feminino , Expressão Gênica , Hibridização In Situ , Hibridização de Ácido Nucleico , Gravidez , Proteínas de Ligação ao Retinol/análise , Proteínas de Ligação ao Retinol/genética , Útero/química , Útero/metabolismo
18.
Mol Reprod Dev ; 38(1): 24-9, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8049061

RESUMO

Communication between the mother and the early developing embryo is mediated by a variety of signals secreted by either the uterus or the embryo to elicit a response from the other. These signals include prostaglandins, proteins, and steroids. Recently, retinol-binding protein (RBP) has been described as a product of both the conceptus and endometrium in several species. Utilizing a cDNA clone to bovine RBP, we have described RBP mRNA expression in the endometrium, early conceptus, and extraembryonic membranes of sheep. Endometrial RBP mRNA expression did not differ between samples collected on day 13 of the estrous cycle and early pregnancy. In cyclic animals, RBP mRNA expression decreased two-fold between days 13 and 16, presumably a result of luteal regression and the consequential withdrawal of progesterone. In pregnant animals, endometrial RBP mRNA expression likewise decreased between days 13 and 16 and remained at this reduced level through day 30, despite the presence of a functional corpus luteum. Initiation of embryonic RBP expression appeared to coincide with early stages of blastocyst elongation at day 13. Levels of expression increased dramatically with conceptus development, peaked on day 23, and declined afterwards. Results from restriction enzyme analysis of genomic DNA indicated that RBP was encoded by a single gene per haploid genome. Differences in the temporal and tissue-specific expression of the protein, despite the apparent utilization of a single gene, suggest complex regulation of RBP gene expression.


Assuntos
Embrião de Mamíferos/metabolismo , Endométrio/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação ao Retinol/genética , Animais , Blastocisto/metabolismo , Feminino , Regulação da Expressão Gênica , Troca Materno-Fetal , Gravidez , Ovinos
19.
Circulation ; 88(5 Pt 2): II413-9, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8222187

RESUMO

BACKGROUND: After catheter injury, the neoendothelium that grows is abnormal in morphology and in acetylcholine-induced generation of endothelium-derived relaxing factor (EDRF). Heparin has been shown to have stimulatory effects on vascular endothelial growth in vitro. Its effect in vivo on neoendothelial cell morphology and metabolism after injury has not been described. We investigated the effect of heparin treatment on the neoendothelium formed after injury. METHODS AND RESULTS: Four groups of New Zealand White rabbits were studied. Group 1 rabbits underwent catheter denudation and were killed 4 weeks after injury without receiving treatment (NO Tx, n = 8). Groups 2 and 3 underwent similar aortic injury, received 2 weeks of treatment with either heparin (n = 7) or low molecular weight heparin (LMWH, n = 5), and were killed at 4 weeks. Group 4 underwent sham operation (SHAM, n = 8). EDRF generation was determined by the relaxation of precontracted aortic rings in an organ bath in response to acetylcholine. The heparin-treated group exhibited a significant improvement in acetylcholine-induced relaxation (27%) versus both LMWH-treated (14%, P = .035) and untreated groups (11%, P = .004), although relaxation was only 50% of that observed in the uninjured control vessels (52%, P = .001). The neoendothelium formed in the heparin-treated group exhibited a more normal histological appearance and was aligned with the direction of blood flow as compared with that observed in the untreated or LMWH-treated groups. CONCLUSIONS: These results demonstrate that in vivo heparin administration enhanced the recovery of EDRF generation and augmented normalization of the morphologic appearance of the neoendothelium.


Assuntos
Aorta Torácica/lesões , Cateterismo/efeitos adversos , Endotélio Vascular/lesões , Heparina de Baixo Peso Molecular/uso terapêutico , Heparina/uso terapêutico , Óxido Nítrico/metabolismo , Acetilcolina/farmacologia , Animais , Aorta Torácica/fisiologia , Endotélio Vascular/fisiologia , Hiperplasia , Masculino , Microscopia Eletrônica de Varredura , Coelhos , Túnica Íntima/patologia
20.
Spine (Phila Pa 1976) ; 18(10): 1373-5, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8211372

RESUMO

We describe a case of thoracic myelopathy in a patient with renal osteodystrophy. The patient had chronic renal failure for longer than 20 years and had skeletal changes indicative of renal osteodystrophy, before the onset of myelopathy. Association between spinal stenosis and this entity has been documented only once before in the lumbar region. This is therefore the first case of thoracic myelopathy due to severe stenosis in just one vertebra in a patient with renal osteodystrophy, which was documented by computed tomography as well as magnetic resonance imaging and proven by histopathology.


Assuntos
Distúrbio Mineral e Ósseo na Doença Renal Crônica/complicações , Estenose Espinal/etiologia , Distúrbio Mineral e Ósseo na Doença Renal Crônica/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estenose Espinal/diagnóstico por imagem , Tomografia Computadorizada por Raios X
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