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1.
Pol J Vet Sci ; 26(2): 307-309, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37389419

RESUMO

A separate, cat-specific hospitalization room away from dogs is recommended to reduce stress in cats; however, this can be difficult for some hospitals to provide. In such cases, measures are undertaken to reduce the cat's stress by providing a place to hide. However, inability to observe the cat's condition may be an obstacle to providing veterinary care. The use of a one-way mirror to create a sheltered environment while allowing observation of the cats was assessed. Five healthy cats were assessed using the Cat Stress Score (CSS) while in a cage with either a transparent panel or a one-way mirror. No significant differences in the CSS between the transparent panel and one-way mirror were observed. Variations in the CSS scores depended on the cat's personality, with friendlier and more sociable cats showing a lower CSS with the one-way mirror. A one-way mirror may be useful to reduce stress in hospitalized cats.


Assuntos
Doenças do Gato , Doenças do Cão , Gatos , Animais , Cães , Hospitalização , Doenças do Gato/terapia
2.
Transplant Proc ; 51(2): 548-550, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30879587

RESUMO

Patients with end-stage renal disease are at a high risk for cardiovascular diseases. It is controversial whether end-stage renal disease patients with low cardiac function can safely accept kidney transplant. Here, we present a 42-year-old kidney transplant recipient with severe mitral regurgitation accompanied by low cardiac function. He wanted to undergo a pre-emptive kidney transplant from his uncle. We decided to perform living kidney transplant prior to cardiac surgery. Despite adequate ultrafiltration and hemodiafiltration before operation, the patient's ejection fraction still remained 35% 1 day before transplant. He showed complete recovery of cardiac function in only 2 days after pre-emptive kidney transplant, although his body weight did not change before and after the operation. Early removal of the uremic toxin or inflammatory cytokines may play a role in rapid improvement of the cardiac function. Increase of vasoactive substances by improvement of kidney function may lead to reduction of afterload and amelioration of cardiac microcirculation. This report also suggests that optimal timing for operation might be important.


Assuntos
Falência Renal Crônica/complicações , Falência Renal Crônica/cirurgia , Transplante de Rim , Insuficiência da Valva Mitral/complicações , Adulto , Humanos , Masculino
3.
Vet Comp Oncol ; 15(2): 557-562, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26762899

RESUMO

Although androgen therapy resistance and poor clinical outcomes are seen in most canine prostate cancer cases, there are only a few tools for analysing canine prostate cancer by using a cell biological approach. Therefore, to evaluate androgen-independent neoplastic cell growth, a new canine prostate cancer cell line (CHP-1) was established in this study. CHP-1 over-expressed the co-chaperone small glutamine-rich tetratricopeptide repeat-containing protein α (SGTA), which is over-expressed in human androgen-independent prostate cancer. The CHP-1 xenograft also showed SGTA over-expression. Although CHP-1 shows poor androgen receptor (AR) signalling upon dihydrotestosterone stimulation, forced expression of AR enabled evaluation of AR signalling. Taken together, these results suggest that CHP-1 will be a useful model for investigating the pathogenesis of androgen-dependent and androgen-independent canine prostate cancer.


Assuntos
Proteínas de Transporte/metabolismo , Doenças do Cão/metabolismo , Neoplasias da Próstata/veterinária , Animais , Linhagem Celular Tumoral , Doenças do Cão/patologia , Cães , Glutamina , Masculino , Camundongos Nus , Transplante de Neoplasias , Próstata/metabolismo , Próstata/patologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Repetições de Tetratricopeptídeos
4.
Pol J Vet Sci ; 19(2): 387-91, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27487514

RESUMO

Carbohydrate is an important source of energy, which can significantly affect postprandial blood glucose and insulin levels in cats. In healthy animals, this is not a big concern; however, in obese and diabetic animals, this is an important detail. In the present study, the impact of four different carbohydrate sources (glucose, maltose, corn starch, and trehalose) on short-term post-prandial serum glucose, insulin, and non-esterified fatty acid (NEFA) concentrations was investigated with four obese cats. Each of the carbohydrate sources was added to a commercial wet food diet for feeding the animals. A significant difference was observed in postprandial glucose, insulin, and NEFA area under the curve (AUC) values between each carbohydrate source in obese cats. Furthermore, glucose and maltose induced the highest postprandial glucose and insulin AUC values, whereas trehalose induced the lowest postprandial glucose and insulin AUC value amongst all carbohydrate sources, respectively, in obese cats. However, trehalose has a higher risk of inducing side effects, such as diarrhea, as compared to other carbohydrate sources. As such, different carbohydrate sources appear to have a very significant impact on post-prandial glycemia and subsequent insulin requirement levels in obese cats. These results might be useful when selecting a prescription diet for obese or diabetic cats. In addition, maltose appears to be capable of inducing experimentally evoked postprandial hyperglycemia in obese cats, which may serve as a good tool for use to check the impact and effectiveness of newly developed oral hypoglycemic drugs or supplements for cats in future experiments.


Assuntos
Glicemia/efeitos dos fármacos , Doenças do Gato/metabolismo , Ácidos Graxos não Esterificados/sangue , Insulina/sangue , Obesidade/veterinária , Período Pós-Prandial , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Gatos , Dieta/veterinária , Feminino , Masculino , Obesidade/dietoterapia
5.
Domest Anim Endocrinol ; 45(2): 79-88, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23827214

RESUMO

Leptin and adiponectin play important roles in carbohydrate and lipid metabolism in different species. Information is limited on the effects of diet, weight gain, and fat mass on their concentrations in cats. This study compared fasting and postprandial blood leptin and total adiponectin concentrations before and after 8 wk of ad libitum feeding to promote weight gain in adult cats (n = 32) fed either a low-carbohydrate, high-protein (23% and 47% ME) or a high-carbohydrate, low-protein (51% and 21% ME) diet. There were significant effects of total, abdominal, and nonabdominal fat mass, but not diet or body weight, on mean 24-h and peak leptin (P < 0.01); observed increases in mean and peak leptin were greatest for abdominal fat mass (50% and 56% increase for every extra 100 g, respectively). After weight gain, postprandial leptin concentration increased markedly relative to when cats were lean, and the duration of the increase was longer after a mean weight gain of 37% with the low-carbohydrate, high-protein diet group compared with 17% with the high-carbohydrate, low-protein group (P ≤ 0.01). Adiponectin was lower than fasting at some time points during the postprandial period in both groups (P ≤ 0.05). For both fasting and mean 24-h adiponectin, there was no significant diet effect (P ≥ 0.19) or changes in weight gain relative to when cats were lean (P ≥ 0.29). In conclusion, fat mass, and not diet, has a large effect on postprandial leptin but not adiponectin concentrations in cats.


Assuntos
Adiponectina/sangue , Composição Corporal/fisiologia , Gatos/sangue , Dieta/veterinária , Leptina/sangue , Gordura Abdominal/fisiologia , Animais , Gatos/fisiologia , Carboidratos da Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Jejum , Humanos , Período Pós-Prandial , Aumento de Peso
6.
Res Vet Sci ; 95(2): 381-8, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23632200

RESUMO

Glucagon-like peptide 1 (GLP-1) is a glucose-lowering, intestinal-derived factor with multiple physiological effects, making it attractive for diabetes therapy. However, the therapeutic potential of endogenous GLP-1 is limited, because of rapid inactivation by dipeptidyl peptidase-4. Recently, enhanced incretin preparations, such as liraglutide, have emerged, which are more resistant to degradation and longer lasting. Liraglutide is a long-acting acylated human GLP-1 receptor agonist, with a 97% amino acid sequence identity to endogenous human GLP-1, and 100% amino acid sequence homology with canine GLP-1. Since liraglutide has yet to be examined for use in dogs, and the incretin effect has been reported to exist in dogs, we sought to initially characterize liraglutide's ability for glycemic control in healthy dogs, under an oral glucose tolerance test (OGTT) environment initially. This was followed up a more realistic scenario involving food with insulin injection +/- liraglutide injection resulting in a glucose curve based study involving dogs suffering from Type 1 diabetes mellitus (T1DM). Overall, liraglutide had a stabilizing effect on glucose levels, maintaining circulating levels between 77.0 and 137.0mg/ml throughout the OGTT test period, resulting in a significant reduction of 13.8% in glucose AUC0-120 min (total area under the curve for 0-120 min) as compared to baseline control in healthy dogs (n=5). Interestingly, the liraglutide associated reduction in circulating glucose was not accompanied by any significant increase in insulin. Moreover, T1DM dogs (n=4) responded favorably to liraglutide treatment, which lead to a significant reduction of 46.0% in glucose AUC0-12h (total area under the curve for 0-12h), and a significant reduction of 66.5% in serum glucose as compared to baseline controls (insulin treatment only). Therefore, liraglutide's prandial glucagon suppressive ability appears to play a key role in its glucose-lowering capability, and offers great potential for use with dogs suffering from T1DM.


Assuntos
Glicemia/efeitos dos fármacos , Diabetes Mellitus Tipo 1/veterinária , Doenças do Cão/tratamento farmacológico , Peptídeo 1 Semelhante ao Glucagon/análogos & derivados , Animais , Área Sob a Curva , Glicemia/metabolismo , Estudos de Casos e Controles , Diabetes Mellitus Tipo 1/tratamento farmacológico , Cães , Feminino , Peptídeo 1 Semelhante ao Glucagon/uso terapêutico , Insulina/sangue , Insulina/metabolismo , Liraglutida , Masculino
7.
Domest Anim Endocrinol ; 41(1): 35-41, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21645805

RESUMO

Although one study showed lower adiponectin concentrations in obese dogs, other recent studies indicate that adiponectin might not be decreased in obese dogs, raising the possibility that the physiology of adiponectin is different in dogs than in humans. The aim of this study was to investigate possible causes of the discrepancy between the two largest studies to date that assessed the association between adiposity and adiponectin concentration in dogs, including the validity of the assay, laboratory error, and the effects of breed, sex, and neuter status on the relationship between adiposity and adiponectin concentrations. Adiponectin concentrations measured with a previously validated adiponectin ELISA were compared with those estimated by Western blotting analysis of reduced and denatured plasma samples. The possibility of laboratory error and the effect of EDTA anticoagulant and aprotinin were tested. Adiponectin concentration was measured by ELISA in 20 lean dogs (10 male and 10 female, 5 neutered in each sex). There was close correlation between adiponectin concentrations measured by ELISA and those estimated by Western blotting analysis (r = 0.90; P < 0.001). There was no substantial effect of EDTA, aprotinin, or laboratory error on the results. There was confounding by neuter status of the relationship between adiposity and adiponectin concentrations, but adiponectin concentrations were not significantly lower in male than in female lean dogs (females, 36 mg/L; males, 26 mg/L; P > 0.20) and were not significantly lower in intact than in neutered lean male dogs (intact, 28 mg/L; neutered, 23 mg/L; P = 0.49). We conclude that the adiponectin ELISA previously validated for use in dogs appears to be suitable for determination of canine adiponectin concentrations and that testosterone does not appear to have a strong effect on plasma adiponectin concentrations in dogs. Obesity might decrease adiponectin concentrations in intact but not in neutered dogs.


Assuntos
Adiponectina/sangue , Adiposidade/fisiologia , Doenças do Cão/sangue , Ensaio de Imunoadsorção Enzimática/veterinária , Obesidade/sangue , Obesidade/veterinária , Animais , Western Blotting , Castração/veterinária , Erros de Diagnóstico/veterinária , Cães , Feminino , Masculino , Reprodutibilidade dos Testes , Caracteres Sexuais
8.
Domest Anim Endocrinol ; 41(1): 24-34, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21474268

RESUMO

The hormonal mediators of obesity-induced insulin resistance and compensatory hyperinsulinemia in dogs have not been identified. Plasma samples were obtained after a 24-h fast from 104 client-owned lean, overweight, and obese dogs. Plasma glucose and insulin concentrations were used to calculate insulin sensitivity and ß-cell function with the use of the homeostasis model assessment (HOMA(insulin sensitivity) and HOMA(ß-cell function), respectively). Path analysis with multivariable linear regression was used to identify whether fasting plasma leptin, adiponectin, or glucagon-like peptide-1 concentrations were associated with adiposity, insulin sensitivity, and basal insulin secretion. None of the dogs were hyperglycemic. In the final path model, adiposity was positively associated with leptin (P < 0.01) and glucagon-like peptide-1 (P = 0.04) concentrations. No significant total effect of adiposity on adiponectin in dogs (P = 0.24) was observed. If there is a direct effect of leptin on adiponectin, then our results indicate that this is a positive relationship, which at least partly counters a negative direct relationship between adiposity and adiponectin. Fasting plasma leptin concentration was directly negatively associated with fasting insulin sensitivity (P = 0.01) and positively associated with ß-cell function (P < 0.01), but no direct association was observed between adiponectin concentration and either insulin sensitivity or ß-cell function (P = 0.42 and 0.11, respectively). We conclude that dogs compensate effectively for obesity-induced insulin resistance. Fasting plasma leptin concentrations appear to be associated with obesity-associated changes in insulin sensitivity and compensatory hyperinsulinemia in naturally occurring obese dogs. Adiponectin does not appear to be involved in the pathophysiology of obesity-associated changes in insulin sensitivity.


Assuntos
Adiponectina/sangue , Doenças do Cão/fisiopatologia , Peptídeo 1 Semelhante ao Glucagon/sangue , Resistência à Insulina/fisiologia , Leptina/sangue , Obesidade/veterinária , Adiposidade/fisiologia , Animais , Glicemia/análise , Cães , Jejum , Insulina/sangue , Células Secretoras de Insulina/fisiologia , Obesidade/fisiopatologia
9.
Res Vet Sci ; 90(3): 396-403, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20708207

RESUMO

Insulin detemir is the first member of a new class of long-acting soluble insulin analogues capable of maintaining the basal level of insulin in humans. In this preliminary study, we investigated the time-action profiles of insulin detemir in normal and diabetic dogs since the use of insulin detemir in canines has yet to be determined. Eight animals were used in our study (three normal and five insulin dependent diabetic dogs). Time-action profiles of insulin detemir were monitored in normal dogs using an artificial pancreas apparatus under euglycemic condition. Blood sampling was performed at 2h intervals post feeding, with insulin administration, in insulin dependent diabetic dogs. Time-action profiles of insulin detemir, in normal dogs, demonstrated that insulin detemir is a long-lasting preparation similar to what has been observed in humans. A pronounced peak was detected at 8-10h while the glucose-lowering effect lasted for over 24h after insulin injection, thus illustrating its longer prolonged peak activity time. Furthermore, intensive glycemic control was achieved with insulin detemir in insulin dependent diabetic dogs, using a lower dosage than NPH insulin and insulin glargine therapeutic doses. Our results indicate that insulin detemir has a greater effect than either NPH insulin or insulin glargine in canines, requiring a lower dose than either insulin preparation. However, using insulin detemir also carries a higher risk of inducing hypoglycemia as compared to either NPH insulin or insulin glargine.


Assuntos
Diabetes Mellitus/veterinária , Doenças do Cão/metabolismo , Cães/metabolismo , Insulina/análogos & derivados , Animais , Glicemia/análise , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/metabolismo , Doenças do Cão/tratamento farmacológico , Feminino , Insulina/sangue , Insulina/farmacocinética , Insulina/uso terapêutico , Insulina Detemir , Insulina Glargina , Insulina Isófana/farmacocinética , Insulina de Ação Prolongada , Masculino
10.
J Phys Condens Matter ; 22(46): 465803, 2010 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-21403377

RESUMO

Ultrafast electron-phonon coupling dynamics in ZnO are investigated by degenerate pump-probe reflectivity measurements using near resonant 400 nm light. Because of the below-gap excitation, photocarriers are excited primarily from deep levels of intrinsic point defects. At least six coherent phonon modes, including two E(2) modes and their combination, longitudinal optical (LO) mode and its overtone (2LO), are observed. Unlike the previous resonant Raman studies using 325 nm light, the intensity of the polar LO phonons is only moderately enhanced by the Fröhlich interaction. The non-polar E(2) phonons decay considerably faster than under visible excitation, indicative of strong deformation potential interaction with photocarriers. The overdamped oscillation centered at around 20 THz is tentatively attributed to the upper branch of the plasmon-phonon coupled mode. The pump-polarization dependence of the phonon amplitudes is consistent with the impulsive Raman generation.

11.
Vet Res Commun ; 33(8): 957-70, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19728131

RESUMO

Glimepiride and nateglinide are two common oral hypoglycemic agents currently being used with humans suffering from Type 2 diabetes mellitus. Neither drug has been tested with cats thus far and it is currently unknown whether either of these drugs exert any effect in cats or not. The objective of this study was to determine the effect of glimepiride and nateglinide on glucose and insulin responses in healthy control cats, in order to determine their potential use in diabetic cats. The intravenous glucose tolerance tests was carried out since it is an excellent test for evaluating pancreatic beta-cell function for insulin secretion. Alterations in the insulin secretion pattern can be perceived as the earliest sign of beta-cell dysfunction in many species, including cats. Nateglinide demonstrated a quick action/short duration type effect with serum glucose nadiring and insulin response peaking at 60 and 20 minutes, respectively. Alternatively, glimepiride is medium-to-long acting with serum glucose nadiring and insulin response peaking at 180 minutes and 60 minutes, respectively. Nateglinide's potency was evident allowing it to induce a 1.5-2 higher preliminary insulin peak (3.7 +/- 1.1 pg/ml) than glimepiride's (2.5 +/- 0.1 pg/ml), albeit only for a short period of time. Because glimepiride and nateglinide have a shared mode of action, no significant differences in overall glucose AUC(0-360 min) (24,435 +/- 2,940 versus 24,782 +/- 2,354 mg min/dl) and insulin AUC(0-360 min) (410 +/- 192 versus 460 +/- 159) in healthy control cats were observed. These findings may provide useful information when choosing a hypoglycemic drug suited for the treatment of diabetic cats depending on the degree of diabetes mellitus the cat is suffering from.


Assuntos
Glicemia/análise , Gatos/sangue , Cicloexanos/farmacologia , Hipoglicemiantes/farmacologia , Insulina/sangue , Fenilalanina/análogos & derivados , Compostos de Sulfonilureia/farmacologia , Animais , Doenças do Gato/sangue , Doenças do Gato/tratamento farmacológico , Gatos/metabolismo , Diabetes Mellitus/sangue , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/veterinária , Feminino , Teste de Tolerância a Glucose/veterinária , Masculino , Nateglinida , Fenilalanina/farmacologia
13.
Res Vet Sci ; 83(1): 5-11, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17140615

RESUMO

A selective beta3-adrenoceptor agonist, AJ-9677, was reported to ameliorate obesity and insulin resistance in KK-Ay mice. We examined the acute and chronic effects of AJ-9677 on obese dogs. Oral administration of AJ-9677 (0.01 or 0.1 mg/kg) to overnight fasted obese beagles produced a dose-dependent rise in the plasma levels of non-esterified fatty acids and insulin in 1h, followed by a gradual drop of the plasma glucose level. It produced no apparent abnormal behaviors, but easily detectable cutaneous flushing. Daily treatment of AJ-9677 at a lower dose (0.01 mg/kg) for three weeks produced no notable change in body weight, but at a higher dose (0.1 mg/kg) it reduced the body weight compared to a placebo treatment after seven weeks. Computed tomographic examinations revealed a remarkable reduction of body fat after the AJ treatment, being consistent with the histological observations that the adipose tissue of AJ-9677-treated dogs consisted of smaller and some multilocular adipocytes. The plasma levels of leptin and adiponectin were decreased and increased, respectively, after the AJ treatment, reflecting the reduction of adiposity. It was concluded that AJ-9677 is useful for the treatment of obesity in the dog.


Assuntos
Acetatos/farmacologia , Tecido Adiposo/efeitos dos fármacos , Agonistas de Receptores Adrenérgicos beta 3 , Fármacos Antiobesidade/farmacologia , Indóis/farmacologia , Obesidade/veterinária , Animais , Glicemia , Cães , Ácidos Graxos não Esterificados/sangue , Feminino , Insulina/sangue , Resistência à Insulina , Masculino , Obesidade/tratamento farmacológico , Obesidade/metabolismo
14.
Res Vet Sci ; 82(1): 11-5, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16919691

RESUMO

Leptin is a cytokine produced by adipocytes, and plays a key role in the regulation of energy balance. In the present study, we measured plasma leptin concentrations of 166 normal and obese dogs visiting veterinary practices, and clarified the influence of age, gender and breed on plasma leptin levels in dogs. Leptin levels were higher in the dogs with higher body condition scores. There was no noticeable influence of age, gender and breed, but those in optimal puppies and obese Miniature Dachshund tended to be lower than those in corresponding groups. We conclude that plasma leptin is a reliable marker of adiposity in dogs regardless of age, gender and breed variations, and thereby useful as a blood biochemistry test for health examinations and treatment of obesity.


Assuntos
Envelhecimento/fisiologia , Composição Corporal/fisiologia , Cães/sangue , Cães/classificação , Leptina/sangue , Caracteres Sexuais , Animais , Feminino , Leptina/fisiologia , Masculino , Especificidade da Espécie
15.
Res Vet Sci ; 80(2): 127-32, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16051287

RESUMO

Adiponectin is a protein synthesized and secreted by adipocytes. Decreased adiponectin is responsible for insulin resistance and atherosclerosis associated with human obesity. We obtained a cDNA clone corresponding to canine adiponectin, whose nucleotide and deduced amino acid sequences were highly identical to those of other species. Adiponectin mRNA was detected in adipose tissues, but not in other tissues, of dogs. When 22 adult beagles were given a high-energy diet for 14 weeks, they became obese, showing heavier body weights, higher plasma leptin concentrations, but lower plasma adiponectin concentrations. The adiponectin concentrations of plasma samples collected from 71 dogs visiting veterinary practices were negatively correlated to plasma leptin concentrations, being lower in obese than non-obese dogs. These results are compatible with those reported in other species, and suggest that adiponectin is an index of adiposity and a target molecule for studies on diseases associated with obesity in dogs.


Assuntos
Adiponectina/sangue , Adiponectina/genética , Tecido Adiposo/metabolismo , Cães/sangue , Cães/genética , Regulação da Expressão Gênica , Obesidade/sangue , Adiponectina/química , Adiponectina/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA Complementar/genética , Feminino , Leptina/sangue , Masculino , Dados de Sequência Molecular , Obesidade/veterinária , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
16.
Vet J ; 169(1): 85-90, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15683767

RESUMO

Leptin is a protein synthesized and secreted primarily by adipocytes, and plays a key role in the regulation of energy balance. We have reported that serum leptin is elevated in obese dogs. In the present study, we examined diurnal variations of serum leptin in the dog, with special references to feeding and fasting cycles. Four male beagles were accustomed to feed once a day at 10:00 h, and blood samples were taken every 3 h for 24-36 h. Serum leptin concentration showed clear diurnal variations, being lowest before food intake (2.3+/-0.5 ng/mL) at 09:00 h, and highest (10.5+/-2.4 ng/mL) at 18:00 h. Such diurnal variations disappeared when the dogs were fasted. Serum insulin also showed diurnal variation with higher levels at 12:00-15:00 h. When insulin or glucose was injected in the fasted dogs to mimic the post-prandial insulin rise, serum leptin concentration was significantly increased in 4-8 h, but in both cases to a lesser extents than those after food intake. The results indicate that serum leptin concentrations change diurnally in association with feeding-fasting cycles in the dog, partially due to changes in insulin secretion.


Assuntos
Ritmo Circadiano , Cães/sangue , Leptina/sangue , Animais , Área Sob a Curva , Ingestão de Alimentos/fisiologia , Jejum/sangue , Insulina/sangue , Insulina/metabolismo , Secreção de Insulina , Masculino , Fatores de Tempo
17.
Phys Rev Lett ; 92(19): 197401, 2004 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-15169444

RESUMO

We have studied the A(1g) coherent phonons in bismuth generated by high fluence ultrashort laser pulses. We observed that the nonlinear regime, where the phonons' oscillation parameters depend on fluence, consists of subregimes with distinct dynamics. Just after entering the nonlinear regime, the phonons become chirped. Increasing the fluence further leads to the emergence of a collapse and revival, which next turns into multiple collapses and revivals. This is explained by the dynamics of a wave packet in an anharmonic potential, where the packet periodically breaks up and reconstitutes in its original form, giving convincing evidence that the phonons are in a quantum state, with no classical analog.

19.
J Vet Med Sci ; 63(10): 1143-5, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11714034

RESUMO

To determine the role of leptin in endotoxin-induced anorexia in ruminants, circulating leptin levels were measured during acute experimental endotoxemia in sheep. Injection of bacterial lipopolysaccharide (450 ng/kg, i.v.) induced anorexia accompanied with fever and increases in serum levels of cortisol, insulin and glucose which are known to stimulate leptin secretion in rodent and human, while it did not affect serum leptin levels at all. These results indicate that serum leptin levels in sheep during acute endotoxemia are differentially regulated from those in rodent and human, and that leptin might not be involved in the endotoxin-induced anorexia in sheep.


Assuntos
Endotoxemia/veterinária , Leptina/sangue , Doenças dos Ovinos/sangue , Doença Aguda , Animais , Anorexia/metabolismo , Anorexia/patologia , Anorexia/veterinária , Glicemia/análise , Ingestão de Alimentos , Endotoxemia/sangue , Endotoxemia/patologia , Feminino , Hidrocortisona/sangue , Insulina/sangue , Lipopolissacarídeos/administração & dosagem , Ovinos , Doenças dos Ovinos/patologia
20.
Res Vet Sci ; 68(2): 109-14, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10756126

RESUMO

Leptin, the product of the ob gene, is one of the key molecules for the regulation of appetite and whole-body energy balance, and thereby for the pathogenesis of obesity. In an attempt to clarify the roles of leptin in obesity and/or related diseases in companion animals, canine leptin c DNA was cloned by amplifying reverse-transcriptase products of RNA extracted from the adipose tissue of the beagle. A c DNA clone of about 3 kbp contained a 501 bp open reading frame coding a 167-amino acid protein with a 21-amino acid signal peptide. The sequence of a 146-amino acid mature leptin was more than 79 per cent identical to those of other mammals. Northern blot analysis revealed abundant expression of leptin m RNA in adipose tissue, but not in other tissues, in adult beagles. When Chinese hamster ovary cells expressing the rat leptin receptor were stimulated with recombinant canine leptin produced by E. coli, some intracellular signal transduction proteins were phosphorylated, indicating that the recombinant leptin was biologically active. The data reported herein will be helpful for further studies of leptin of the dog in health and disease.


Assuntos
Cães/genética , Leptina/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Células CHO , Galinhas , Clonagem Molecular , Cricetinae , DNA Complementar/química , Proteínas de Ligação a DNA/metabolismo , Cães/metabolismo , Escherichia coli , Expressão Gênica , Humanos , Leptina/metabolismo , Masculino , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Dados de Sequência Molecular , Fosforilação , Ratos , Proteínas Recombinantes/metabolismo , Fator de Transcrição STAT3 , Suínos , Transativadores/metabolismo
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