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1.
Trop Anim Health Prod ; 52(4): 1699-1705, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31865537

RESUMO

Co-infections caused by trypanosomes and gastro-intestinal nematodes (GINs) compromise cattle productivity and their control requires a holistic approach. The effectiveness of trypanocides and anthelmintics is compromised by increasing resistance. Use of combined chemotherapeutic products for synergy, mainly practiced in human medicine, is gaining importance in livestock. A trial to evaluate efficacy of VERYL®, containing diminazene diaceturate (3.5 mg/kg body weight) and levamisole chloride (5 mg/kg body weight) for the control of GINs in cattle, was conducted at KALRO-VSRI Muguga, Kenya, between June and August 2016. Thirty-eight cattle aged between 6 and 12 months, naturally infected with GINs, were randomly allocated into two groups; a treatment group received VERYL® intra-muscularly at 10 mL/100 kg bwt and a control group which received Veriben® (Diminazene aceturate) at 3.5 mg/kg bwt. Faecal egg counts (FECs), coproculture, packed cell volume (PCV) and local tolerance at the injection site were measured during the study. FECs were comparable between the treatment and control groups at day 0. However, treatment of cattle with VERYL significantly (p < 0.001) reduced FECs by day 7 and sustained to day 21 post-treatment. Coproculture results for the treatment and control groups revealed presence of Haemonchus, Cooperia, Ostertagia, Trichostrongylus and Oesophagostomum species. Cattle treated with VERYL® had a significant (p < 0.05) reduction in larval recoveries compared to the control group. VERYL® had minimal adverse effects which cleared after a short while and is thus recommended for controlling GINs in cattle.


Assuntos
Anti-Helmínticos/uso terapêutico , Doenças dos Bovinos/tratamento farmacológico , Diminazena/análogos & derivados , Levamisol/uso terapêutico , Infecções por Nematoides/veterinária , Animais , Bovinos , Diminazena/uso terapêutico , Fezes/parasitologia , Haemonchus/isolamento & purificação , Quênia , Infecções por Nematoides/tratamento farmacológico , Contagem de Ovos de Parasitas/veterinária , Distribuição Aleatória , Trichostrongylus/isolamento & purificação
2.
J Dairy Sci ; 102(12): 11670-11680, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31521356

RESUMO

The abrupt cessation of milking at dry-off may induce milk leakage, which may increase the risk of new intramammary infections (IMI). This study assessed the efficacy of 1 i.m. injection of 5.6 mg of cabergoline (Velactis, Ceva Santé Animale, Libourne, France) at drying-off on milk leakage after dry-off and new IMI across the dry period and postcalving compared with a placebo (negative control) and an intramammary antibiotic treatment (positive control) under field conditions. The study was a double-blind, randomized, 3-arm, multicenter, clinical trial performed under Good Clinical Practice conditions. Data from 900 dairy cows of various breeds from 63 farms in France, Germany, and Hungary were analyzed. Only quarters with no bacterial growth at drying-off and a cow somatic cell count ≤200,000 cells/mL were included. Quarters infected with major or minor pathogens or cows with high somatic cell count at time of inclusion were excluded. Cows that qualified for the study were visited 7 times in total before and after drying-off and after calving. Presence (yes/no) of milk leakage was recorded on the day after dry-off. A new infected quarter (new IMI) was defined as one with a major pathogen present in any one of the 2 postcalving samples. Two mixed logistic regression models were fitted to the data to evaluate the efficacy of cabergoline in the reduction of milk leakage and new IMI. One i.m. injection of cabergoline at drying-off significantly reduced the incidence of milk leakage the day after dry-off compared with both placebo and antibiotic treatment. Cabergoline-treated cows significantly reduced the risk of new IMI by major pathogens across the dry period and postcalving by 21% when compared with placebo cows (20.5 vs. 26.0%, respectively). However, when milk leakage was added to the model, the significance of cabergoline was reduced. We interpreted this to show that milk leakage is an intervening variable between treatment with cabergoline and lower risk of new IMI. The antibiotic treatment significantly decreased the odds of new IMI compared with both cabergoline and placebo. However, because several countries are currently disallowing the preventive use of antibiotics at dry-off in noninfected quarters, the dry-off facilitator cabergoline may therefore be of particular value to reduce the risk of new IMI across the dry period.


Assuntos
Cabergolina/farmacologia , Doenças dos Bovinos/fisiopatologia , Leite/metabolismo , Animais , Antibacterianos/farmacologia , Bovinos , Contagem de Células/veterinária , Indústria de Laticínios , Método Duplo-Cego , Feminino , França , Alemanha , Hungria , Lactação/efeitos dos fármacos , Modelos Logísticos , Glândulas Mamárias Animais/efeitos dos fármacos , Glândulas Mamárias Animais/fisiopatologia
3.
J Dairy Sci ; 100(4): 3220-3232, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28161172

RESUMO

In recent years, relationships between high milk yield at dry off, higher prevalence for new intramammary infections, and stress were evaluated. Considering increasing milk yield, dry off methods need to be refined to ensure udder health and animal welfare, especially in high-yielding dairy cows. The present work evaluated the effect of a single cabergoline injection (Velactis, Ceva Santé Animale, Libourne, France) at dry off on udder pressure, milk leakage, and signs of udder pain after dry off. A total of 234 high-yielding (≥16 kg of milk/d) dairy cows was enrolled 7 d before and followed up until 14 d after dry off. Cows were dried off without preparation (i.e., no feed change or intermittent milking before dry off) and treated with a single i.m. injection of 5.6 mg of cabergoline (n = 115) or placebo (n = 119) after last milking. Udder characteristics were measured 4 d before (i.e., before and after milking) and 1, 2, 3, 7, 10, and 14 d after dry off. Udder pressure was evaluated utilizing a hand-held dynamometer. Milk leakage and signs of udder pain were noted as binary variables. Whereas udder pressure baseline values after last milking did not differ between treatment groups (0.541 ± 0.15 kg), cabergoline significantly reduced udder pressure in primiparous but not in multiparous cows after dry off. Differences between cabergoline- and placebo-treated primiparous cows could be evaluated until 3 d after dry off. The first day after dry off, udder pressure in placebo- and cabergoline-treated cows increased by 115% and 42.3%, respectively. Whereas pressure values in placebo cows were highest on the first day after dry off (1.16 ± 0.61 kg) and slowly decreased afterward, udder pressure in cows treated with cabergoline had a slower increase and peak only 2 d after dry off (0.94 ± 0.44 kg). Furthermore, cabergoline caused a reduction of milk leakage, a known factor for new intramammary infections. Only 11.3% of cows treated with cabergoline showed milk leakage compared with 21.0% placebo-treated cows. Additionally, cows with placebo treatment were 2.8 times as likely to show signs of udder pain compared with cows treated with cabergoline. An effect of cabergoline on udder pressure, milk leakage, and udder pain was limited to the first week after dry off. Our data provide evidence that a single injection of cabergoline reduces risk factors for udder health and animal welfare problems around dry off in high-yielding dairy cows with more than 16 kg of milk/d. Further research is warranted, however, to investigate if cabergoline at dry off can also be used to reduce new intramammary infection rates and improve animal welfare after dry off.


Assuntos
Ergolinas/farmacologia , Lactação/efeitos dos fármacos , Glândulas Mamárias Animais/efeitos dos fármacos , Animais , Cabergolina , Bovinos , Indústria de Laticínios , Feminino , Injeções , Leite , Paridade
4.
J Dairy Sci ; 100(12): 9787-9798, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28964519

RESUMO

The inhibition of prolactin release using cabergoline, a dopamine agonist, is an effective strategy to accelerate the changes in mammary secretion composition after drying-off. The objective of this study was to determine how cabergoline may affect mammary tissue remodeling during early involution. Holstein dairy cows were treated with either a single i.m. administration of 5.6 mg of cabergoline (Velactis, Ceva Santé Animale, Libourne, France, n = 7) or placebo (n = 7) at the time of drying-off. Mammary biopsy samples were collected 1 wk before drying-off (d -6), after 30 h of milk accumulation (d 1), and again 8 d following drying-off (d 8) to determine changes in gene expression, lactoferrin content, and cell turnover. Blood and mammary secretion samples were collected at d -6 and again at d 1, 2, 3, 4, 8, and 14 following the abrupt cessation of lactation to evaluate indicators of blood-milk barrier integrity and other markers of mammary tissue remodeling. Cabergoline induced less SLC2A1, BAX, CAPN2, and IGFBP5 mRNA expression. In contrast, cabergoline did not modify changes in cell proliferation and apoptosis. Following the cessation of lactation, changes in mammary secretion composition (Na+ and K+) and blood lactose concentrations were indicative of a loss in the blood-milk barrier function in both treatment groups. Cabergoline treatment affected only Na+ and K+ concentrations at d 1, suggesting a moderate increase in tight junction permeability. The increase in the activity of MMP9 and in mammary epithelial cell concentration in mammary secretions was greater in cabergoline-treated cows than in control cows, suggesting more mammary tissue remodeling. The increase in lactoferrin immunostaining in the mammary tissue occurred earlier for cabergoline-treated cows than for control cows, and was essentially localized in the stroma. Changes in some key markers of mammary involution suggest that cabergoline accelerates mammary gland remodeling. Thus, a single injection of cabergoline after the last milking would facilitate drying-off by enhancing mammary gland involution.


Assuntos
Bovinos/fisiologia , Ergolinas/farmacologia , Lactação/efeitos dos fármacos , Glândulas Mamárias Animais/efeitos dos fármacos , Prolactina/antagonistas & inibidores , Animais , Biomarcadores , Cabergolina , Indústria de Laticínios , Feminino , Injeções Intramusculares/veterinária , Lactação/fisiologia , Glândulas Mamárias Animais/fisiologia
5.
J Dairy Sci ; 99(7): 5707-5718, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27179868

RESUMO

Dairy cattle require a dry period between successive lactations to ensure optimal milk production. Because prolactin (PRL) is necessary for the initiation and maintenance of milk production, strategies that can inhibit PRL secretion might hasten the involution process. The objective of this study was to determine the effect of the PRL release inhibitor cabergoline on markers of mammary gland involution during the early dry period. To assess the effect of cabergoline treatment on mammary gland involution, 14 Holstein dairy cows in late lactation were treated with either a single i.m. administration of 5.6mg of cabergoline (Velactis, Ceva Santé Animale, Libourne, France, n=7) or placebo (n=7) at the time of dry-off. Blood samples and mammary secretion samples were collected 6d before dry-off and again 1, 2, 3, 4, 8, and 14d following the abrupt cessation of lactation. Blood samples were used to determine plasma PRL concentrations. Mammary secretion samples were used to determine somatic cell count, milk fat, lactose, true protein content, and concentrations of α-lactalbumin, lactoferrin, and citrate. Following the cessation of lactation, changes in mammary secretion composition indicated diminished milk synthesis, including reduced concentrations of α-lactalbumin, citrate, and lactose. In contrast, milk somatic cell count, percent total protein, percent fat content, and lactoferrin concentrations significantly increased as involution progressed. Cabergoline treatment decreased the plasma PRL concentrations during the first week of dry-off, compared with the control treatment. No significant differences in citrate, α-lactalbumin, or protein content were observed between treatment groups. The most dramatic changes in secretion composition as a consequence of cabergoline treatment occurred during the first week of the dry period, when lactose concentrations and the citrate:lactoferrin molar ratio were lower and lactoferrin concentrations higher than in the control cows. Cabergoline treatment also tended to increase fat content and somatic cell count more rapidly following dry-off compared with the control group. These changes in mammary secretion composition following the abrupt cessation of lactation indicate that cabergoline treatment facilitated dry-off and effectively accelerated mammary gland involution.


Assuntos
Ergolinas/farmacologia , Glândulas Mamárias Animais/efeitos dos fármacos , Prolactina/metabolismo , Animais , Cabergolina , Bovinos , Contagem de Células/veterinária , Feminino , Lactação/efeitos dos fármacos , Leite/metabolismo , Prolactina/sangue
6.
Reprod Fertil Dev ; 26(2): 328-36, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23439105

RESUMO

The aim of the present study was to investigate the effect of short-term progesterone (P4) supplementation during the early metoestrous period on circulating P4 concentrations and conceptus development in cattle. The oestrous cycles of cross-bred beef heifers were synchronised using a 7-day P4-releasing intravaginal device (PRID® Delta; 1.55 g P4) treatment with administration of a prostaglandin F(2α) analogue (Enzaprost; CEVA Sante Animale) the day before PRID® Delta removal. Only those heifers recorded in standing oestrus (Day 0) were used. In Experiment 1, heifers were randomly assigned to one of five groups: (1) control: no treatment; (2) placebo: insertion of a blank device (no P4) from Day 3 to Day 7; (3) insertion of a PRID® Delta from Day 3 to Day 7; (4) insertion of a PRID® Delta from Day 3 to Day 5; or (5) insertion of a PRID® Delta from Day 5 to Day 7. In vitro-produced blastocysts were transferred to each heifer in Groups 2-5 on Day 7 (n=10 blastocysts per heifer) and conceptuses were recovered when heifers were killed on Day 14. Based on the outcome of Experiment 1, in Experiment 2 heifers were artificially inseminated at oestrus and randomly assigned to one of three treatment groups: (1) placebo; (2) PRID from Day 3 to Day 5; or (3) PRID from Day 3 to Day 7. All heifers were killed on Day 16 and recovered conceptuses were incubated in synthetic oviducal fluid medium for 24 h; spent media and uterine flushes were analysed for interferon-τ (IFNT). In both experiments, daily blood samples were taken to determined serum P4 concentrations. Data were analysed using the PROC MIXED procedure of SAS (SAS Institute, Cary, NC, USA). Insertion of a PRID resulted in an increase (P<0.05) in serum P4 that declined following removal. In Experiment 1, P4 supplementation from Day 3 to Day 5 (17.0±1.4 mm) or Day 3 to Day 7 (11.3±2.3 mm) increased conceptus length compared with placebo (2.1±1.8 mm). Serum P4 was significantly lower from Day 9 to Day 14 (P<0.05) and the weight of the Day 14 corpus luteum (CL) was lower in the PRID Day 3-7 group than the placebo or control groups. In Experiment 2, supplementation from Day 3 to Day 5 (94.0±18.8 mm) or Day 3 to Day 7 (143.6±20.6 mm) increased conceptus length on Day 16 compared with placebo (50.3±17.4 mm). Serum P4 was significantly lower in the two supplemented groups following PRID removal compared with placebo (P<0.05) and was associated with a lower CL weight in the Day 3-7 group. Conceptus length was strongly correlated with the IFNT concentration in the uterine flush (r=0.58; P=0.011) and spent culture medium (r=0.68; P<0.002). The findings of the present study highlight the somewhat paradoxical effects of P4 supplementation when given in the early metoestrous period in terms of its positive effect on conceptus development and its potentially negative effects on CL lifespan.


Assuntos
Corpo Lúteo/efeitos dos fármacos , Implantação do Embrião/efeitos dos fármacos , Fármacos para a Fertilidade Feminina/administração & dosagem , Fertilidade/efeitos dos fármacos , Progesterona/administração & dosagem , Técnicas de Reprodução Assistida/veterinária , Administração Intravaginal , Animais , Blastocisto/efeitos dos fármacos , Blastocisto/fisiologia , Bovinos , Corpo Lúteo/fisiologia , Esquema de Medicação , Técnicas de Cultura Embrionária/veterinária , Transferência Embrionária/veterinária , Desenvolvimento Embrionário/efeitos dos fármacos , Ciclo Estral/efeitos dos fármacos , Ciclo Estral/fisiologia , Feminino , Fármacos para a Fertilidade Feminina/sangue , Fertilização in vitro/veterinária , Inseminação Artificial/veterinária , Gravidez , Progesterona/sangue , Fatores de Tempo
7.
J Dairy Sci ; 96(6): 3774-87, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23587391

RESUMO

Sudden dry-off is an established management practice in the dairy industry. But milk yield has been increasing continuously during the last decades. There is no information whether the dry-off procedure, which often results in swollen and firm udders, causes stress, particularly in high-producing dairy cows. Therefore, we evaluated the effect of a sudden dry-off on extramammary udder pressure and the concentration of fecal glucocorticoid metabolites (i.e., 11,17-dioxoandrostane, 11,17-DOA) as an indirect stress parameter. Measurements were carried out within the last week before dry-off and until 9d after dry-off considering 3 groups of milk yield (i.e., low: <15 kg/d, medium: 15-20 kg/d, and high: >20 kg/d). Udder pressure increased in all yield groups after dry-off, peaked at d 2 after dry-off and decreased afterwards. Pressures were highest in high-yielding cows and lowest in low-yielding cows. But only in high-yielding cows was udder pressure after dry-off higher than before dry-off. Baseline 11,17-DOA concentrations depended on milk yield. They were highest in low-yielding (121.7 ± 33.3 ng/g) and lowest in high-yielding cows (71.1 ± 30.0 ng/g). After dry-off, 11,17-DOA increased in all yield groups and peaked at d 3. Whereas in medium- and high-yielding cows 11,17-DOA levels differed significantly from their respective baseline during the whole 9-d measuring period, low-yielding cows showed elevated 11,17-DOA levels only on d 3 after dry-off. However, especially the increase in 11,17-DOA after dry-off between the 3 yield groups was considerably different. Mean 11,17-DOA increase from baseline to d 3 was highest in high-yielding cows (129.1%) and considerably lower in low-yielding cows (40.1%). The highest fecal 11,17-DOA concentrations were measured on d 3 after dry-off, indicating that the stress was most intense on d 2, which is due to an 18-h time lag; at about the same time, udder pressure peaked. Our results showed a negligible effect of a sudden dry-off on low-yielding cows. High-yielding cows, however, faced high extramammary pressures and increased glucocorticoid production. Considering animal welfare aspects, a review of the current dry-off strategies might be warranted.


Assuntos
Bovinos/fisiologia , Fezes/química , Glucocorticoides/análise , Lactação/fisiologia , Glândulas Mamárias Animais/fisiologia , Estresse Fisiológico/fisiologia , Androstanos/análise , Animais , Indústria de Laticínios/métodos , Feminino , Hidrocortisona/análise , Hidrocortisona/metabolismo , Pressão
8.
Biochim Biophys Acta ; 1517(3): 424-9, 2001 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-11342221

RESUMO

We have cloned and sequenced a 5 kb genomic fragment in the 5'-flanking region of the human myosin phosphatase target subunit 1. The transcription initiation site (+1) was 268 bp upstream from the translation start site. In this promoter there are no canonical TATA or CAAT box elements but there is a high GC-rich sequence. Basal promoter activity was due to the GC-rich region that contained one Sp1 transcription factor binding site, thus demonstrating that the MYPT1 gene is a housekeeping gene. Luciferase reporter assays showed the presence of two regions for positive elements and one for a negative element.


Assuntos
Fosfoproteínas Fosfatases/genética , Sequência de Bases , Sítios de Ligação , Células Cultivadas , Clonagem Molecular , DNA/genética , DNA/metabolismo , Primers do DNA/genética , Células HeLa , Humanos , Luciferases/genética , Dados de Sequência Molecular , Fosfatase de Miosina-de-Cadeia-Leve , Fosfoproteínas Fosfatases/química , Regiões Promotoras Genéticas , Subunidades Proteicas , Fator de Transcrição Sp1/metabolismo , Transcrição Gênica
9.
Cell Signal ; 8(8): 575-81, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9115850

RESUMO

In extracts of human platelets, three isoenzymes of cyclic nucleotide phosphodiesterase (PDE), namely, PDE2, PDE3, and PDE5, were identified; activities of PDE1 and PDE4 were not detected. In human platelets, the cGMP-hydrolytic activity was about six times higher than the cAMP-hydrolytic activity, and PDE5 and PDE3 are the major phosphodiesterase isoenzymes that hydrolyze cGMP and cAMP, respectively. PDE5 exhibited organ-specific expression in humans, and platelets were among the tissues richest in PDE5. A novel inhibitor of PDE5, sodium 1-[6-chloro-4-(3,4-methylenedioxybenzyl)aminoquinazolin-2-yl ] piperidine-4-carboxylate sesquihydrate (E4021), was a potent and highly selective inhibitor of human platelet PDE5. However, E4021 (up to 10 microM) did not inhibit 9,11-epithio-11,12-methano-thromboxane A2-induced platelet aggregation, in vitro. E4021 plus SIN-1 (3-morpholino-sydnonimine), at concentrations that had little effect individually, inhibited aggregation. These results suggest the unique distribution of phosphodiesterase isoenzymes in human platelets and the PDE5 inhibitors might be useful as a new class of antiplatelet drugs.


Assuntos
Plaquetas/enzimologia , Isoenzimas/sangue , Diester Fosfórico Hidrolases/sangue , 3',5'-GMP Cíclico Fosfodiesterases , Plaquetas/efeitos dos fármacos , Nucleotídeo Cíclico Fosfodiesterase do Tipo 5 , Humanos , Técnicas In Vitro , Isoenzimas/isolamento & purificação , Molsidomina/análogos & derivados , Molsidomina/farmacologia , Inibidores de Fosfodiesterase/farmacologia , Diester Fosfórico Hidrolases/isolamento & purificação , Ftalazinas/farmacologia , Piperidinas/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/farmacologia , Quinazolinas/farmacologia , Transdução de Sinais , Tromboxano A2/análogos & derivados , Tromboxano A2/farmacologia , Distribuição Tecidual
10.
Cell Signal ; 11(9): 671-6, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10530875

RESUMO

Cyclic GMP-dependent protein kinase (PKG) phosphorylated, in vitro, the large (MYPT1) and small (M20) regulatory subunits of myosin phosphatase (MP) with maximum stoichiometries of 1.8 and 0.6 mol of phosphate/mol subunit, respectively. The phosphorylation of these subunits by PKG did not affect the phosphatase activity towards the 20 kDa myosin light chain. However, phosphorylation of the MP holoenzyme decreased the binding of MP to phospholipid. The phosphorylation of the serine residue of the C-terminal part of MYPT1 was crucial for these interactions. These results suggest that the phosphorylation of MP by PKG is not a direct mechanism in activating MP activity, and that other indirect mechanisms, including the interaction between MP and phospholipids, might be candidates for Ca2+ desensitization via cGMP in smooth muscle.


Assuntos
Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Fosfoproteínas Fosfatases/metabolismo , Animais , Bovinos , Moela não Aviária , Fosfatase de Miosina-de-Cadeia-Leve , Fosforilação
11.
Clin Cancer Res ; 5(8): 2065-8, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10473087

RESUMO

Lymph node metastasis is an important prognostic factor for rectal carcinoma, but only a few attempts at defining the relationship between lymph node micrometastases and prognosis have been made. The purpose of this study was to examine the correlation between the presence of micrometastases and prognosis in patients with rectal carcinoma. Six hundred forty-four lymph nodes were dissected from 42 patients with Dukes' B rectal carcinoma and stained immunohistochemically using a monoclonal antibody, CAM5.2, that binds cytokeratin. Clinicopathological factors, rate of recurrence, and prognosis were compared among patients with and without micrometastases. Micrometastases were detected in 19 lymph nodes (19 of 644 = 2.9%) from 9 patients (9 of 42 = 21.4%). The presence of micrometastases was not related to clinicopathological factors. There were significant differences in recurrence rates (5 of 9 versus 5 of 33, P = 0.02), relapse-free survival rates (P = 0.04), and 10-year survival rates (P = 0.03) between patients with and without micrometastases. Immunohistochemistry successfully identified micrometastatic foci in lymph nodes missed with conventional staining methods. The existence of micrometastases influenced the prognosis in patients with Dukes' B rectal carcinoma.


Assuntos
Anticorpos Monoclonais/metabolismo , Carcinoma/diagnóstico , Carcinoma/secundário , Queratinas/metabolismo , Metástase Linfática/diagnóstico , Neoplasias Retais/diagnóstico , Carcinoma/mortalidade , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Neoplasias Retais/mortalidade , Recidiva , Taxa de Sobrevida
12.
FEBS Lett ; 448(1): 101-4, 1999 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-10217418

RESUMO

The dephosphorylation of the myosin light chain kinase and protein kinase C sites on the 20 kDa myosin light chain by myosin phosphatase was investigated. The myosin phosphatase holoenzyme and catalytic subunit, dephosphorylated Ser-19, Thr-18 and Thr-9, but not Ser-1/Ser-2. The role of noncatalytic subunits in myosin phosphatase was to activate the phosphatase activity. For Ser-19 and Thr-18, this was due to a decrease in Km and an increase in k(cat) and for Thr-9 to a decrease in Km. Thus, the distinction between the various sites is a property of the catalytic subunit.


Assuntos
Cadeias Leves de Miosina/metabolismo , Fosfoproteínas Fosfatases/metabolismo , Animais , Sítios de Ligação , Bovinos , Galinhas , Humanos , Músculo Liso/enzimologia , Quinase de Cadeia Leve de Miosina/metabolismo , Fosfatase de Miosina-de-Cadeia-Leve , Fosforilação , Proteína Quinase C/metabolismo
13.
J Nucl Med ; 40(6): 895-903, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10452303

RESUMO

UNLABELLED: This study assesses feasibility and diagnostic accuracy of simultaneous stress 99mTc-sestamibi/rest 201 TI dual-isotope myocardial perfusion SPECT with Moore's correction method, in which contamination originating from lead x-rays produced in a collimator was subtracted in the 201TI windows. METHODS: Eighty-one patients with suspected coronary artery disease received exercise 99mTc-sestamibi injection, followed by rest 201TI injection 50 min later, and dual-isotope SPECT was performed (group 1). These results were compared with coronary angiographic findings. Furthermore, to estimate the accuracy of Moore's correction method, 201TI crosstalk into the 99mTc acquisition window (group 2A, n = 20) and 99mTc crosstalk into the 201TI acquisition windows (group 2B, n = 20) were studied. For group 2A, stress 99mTc-sestamibi SPECT (single 99mTc-sestamibi SPECT) was performed, followed by 201TI injection at rest and dual-isotope SPECT acquisition 50 min later. For group 2B, rest 201TI SPECT (single 201TI SPECT) was performed, followed by 99mTc-sestamibi injection at rest and dual-isotope SPECT acquisition 30 min later. RESULTS: Sensitivity and specificity in group 1 were 83% and 99%, respectively, when > or =75% coronary artery narrowing was considered significant. In groups 2A and 2B, SPECT images were divided into 24 segments, and relative regional uptake in each segment was obtained. In group 2A, relative regional uptake of single 99mTc-sestamibi SPECT correlated well with that of dual-isotope SPECT (r = 0.942). In group 2B, relative regional uptake of single 201TI SPECT correlated well with that of dual-isotope SPECT (r = 0.935). Furthermore, in low 201TI uptake segments with relative regional uptake in both single- and dual-isotope SPECT of < or =70%, the degree of concordance between single- and dual-rest 201TI was considered to be high with Bland-Altman analysis and the kappa statistic. Comparison of perfusion defect type demonstrated that, of 22 stress defects within infarct zones, 95% were irreversible and 5% were reversible. In contrast, of 28 stress defects within stenosed vessel zones in noninfarct zones, 89% were reversible and 11% were irreversible (P < 0.0001 versus infarct zones). CONCLUSION: Simultaneous dual-isotope imaging with Moore's correction method is feasible, with acceptable accuracy for detection of coronary artery disease and a small amount of crosstalk into each window.


Assuntos
Doença das Coronárias/diagnóstico por imagem , Compostos Radiofarmacêuticos , Tecnécio Tc 99m Sestamibi , Radioisótopos de Tálio , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Idoso , Interpretação Estatística de Dados , Estudos de Avaliação como Assunto , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Descanso , Sensibilidade e Especificidade
14.
Am J Cardiol ; 88(8): 863-6, 2001 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-11676948

RESUMO

The benefits of atrial natriuretic peptide (ANP) in patients with congestive heart failure (CHF) have been demonstrated. However, the myocardial actions of ANP remain unclear. Using relatively load-insensitive left ventricular pressure-volume analysis, the myocardial and load-altering actions of ANP in patients with moderate CHF were studied. After obtaining steady-state data using micromanometers and conductance catheters, ANP was infused in 9 patients with CHF at 0.01 and 0.1 microg/kg/min for 30 minutes, respectively. Hemodynamic variables, plasma ANP, and cyclic guanosine monophosphate (cGMP) levels were determined before and 30 minutes after each ANP infusion. ANP at 0.01 microg/kg/min increased plasma ANP and cGMP levels from 73 +/- 34 to 139 +/- 34 pg/ml and from 4 +/- 1 to 8 +/- 2 pmol/ml, respectively. ANP infusion caused a significant decrease in end-systolic pressure without any changes in heart rate. End-diastolic pressure was significantly decreased but there was no significant change in left ventricular end-diastolic volume. The time constant for isovolumetric relaxation was decreased. ANP infusion at 0.1microg/kg/min caused further decreases in end-systolic pressure, end-diastolic pressure and volume, and the time constant for isovolumetric relaxation (p <0.05) without any changes in heart rate. The slope of the end-systolic pressure-volume relation was increased from 1.3 +/- 0.2 to 1.6 +/- 0.3 mm Hg/ml (p <0.05), indicating increased contractility. Plasma ANP and cGMP levels were increased to 422 +/- 44 pg/ml and 16 +/- 3 pmol/ml, respectively. Thus, ANP infusion increased cGMP generation, decreased afterload and preload, and improved left ventricular systolic and diastolic function.


Assuntos
Fator Natriurético Atrial/farmacologia , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/fisiopatologia , Função Ventricular Esquerda/efeitos dos fármacos , Fator Natriurético Atrial/sangue , Fator Natriurético Atrial/uso terapêutico , Hemodinâmica/efeitos dos fármacos , Humanos , Pessoa de Meia-Idade
15.
Am J Cardiol ; 85(9): 1054-9, 2000 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-10781751

RESUMO

Although antiplatelet therapy with a specific inhibitor of phosphodiesterase-3 cilostazol improves stent patency compared with use of aspirin (ASA) alone, the specific role of cilostazol on platelet aggregation in patients with acute myocardial infarction (AMI) is less well understood. Thirty-six patients with AMI who were successfully treated with primary angioplasty were randomized to 3 antiplatelet regimens: ASA alone (n = 12), ASA + ticlopidine (n = 12), and ASA + cilostazol (n = 12). We measured shear stress-induced platelet aggregation (SIPA) using a modified cone-plate viscometer on admission and on day 7, and evaluated the inhibitory effects of combination therapy with ASA + cilostazol on SIPA. Compared with cases of stable coronary artery disease, significant increases in SIPA and plasma von Willebrand factor activity were observed in patients with AMI before they received antiplatelet therapy. On day 7 after primary angioplasty, ASA did not inhibit SIPA (65 +/- 15% vs 57 +/- 11%, p = 0.086), whereas both combination therapies of ASA + ticlopidine and ASA + cilostazol significantly inhibited SIPA in patients with AMI (ASA + ticlopidine: 61 +/- 15% vs 45 +/- 13%, p <0. 0001; ASA + cilostazol: 64 +/- 14% vs 43 +/- 9%, p <0.005). There was a significant correlation of SIPA with adenosine diphosphate (ADP)-induced platelet aggregation (r = 0.412, p = 0.003) and with plasma von Willebrand factor activity (r = 0.461, p = 0.0008). These data suggest that patients with AMI have increased platelet aggregability in response to high shear stress. Combined antiplatelet therapy with ASA + cilostazol appears to be as effective as therapy with ASA + ticlopidine for reducing SIPA in patients with AMI who are undergoing primary angioplasty.


Assuntos
Infarto do Miocárdio/tratamento farmacológico , Inibidores da Agregação Plaquetária/uso terapêutico , Agregação Plaquetária , Tetrazóis/uso terapêutico , Idoso , Aspirina/uso terapêutico , Cilostazol , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/terapia , Agregação Plaquetária/efeitos dos fármacos , Ticlopidina/uso terapêutico , Fator de von Willebrand/análise
16.
Chest ; 104(6): 1905-6, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7902809

RESUMO

We encountered a 52-year-old man with Takayasu's disease (pulseless disease) and severe respiratory failure due to recurrent pulmonary hemorrhage. Angiography revealed occlusion of multiple branches of the pulmonary artery, which were filled via collateral circulation from the coronary, intercostal, and intermammary arteries. This is a rare case that causes massive pulmonary bleeding and respiratory failure in Takayasu's arteritis.


Assuntos
Hemorragia/etiologia , Pneumopatias/etiologia , Insuficiência Respiratória/etiologia , Arterite de Takayasu/complicações , Hemorragia/diagnóstico por imagem , Humanos , Pneumopatias/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Artéria Pulmonar/diagnóstico por imagem , Radiografia , Recidiva
17.
Chest ; 113(2): 555-6, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9498986

RESUMO

A patient with clinical features consistent with pulmonary embolism showed no improvement despite therapy with tissue-plasminogen activator and full-dose heparin. Transvenous catheter suction biopsy was successful in establishing an antemortem histologic diagnosis of primary pulmonary artery leiomyosarcoma. Urgent surgical intervention was performed.


Assuntos
Biópsia/métodos , Leiomiossarcoma/patologia , Artéria Pulmonar/patologia , Neoplasias Vasculares/patologia , Idoso , Anticoagulantes/uso terapêutico , Cateterismo , Diagnóstico Diferencial , Feminino , Heparina/uso terapêutico , Humanos , Leiomiossarcoma/cirurgia , Ativadores de Plasminogênio/uso terapêutico , Pneumonectomia , Artéria Pulmonar/cirurgia , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/tratamento farmacológico , Sucção , Ativador de Plasminogênio Tecidual/uso terapêutico , Neoplasias Vasculares/cirurgia
18.
Virchows Arch ; 439(2): 185-90, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11561759

RESUMO

It has become clear that deposition of extracellular matrix(ECM) proteins is a major cause of human restenosis after percutaneous coronary angioplasty (PTCA). To define the composition and organization of the involved ECM in human restenotic tissue, we morphologically and semiquantitatively analyzed specimens obtained by means of directional coronary atherectomy at various stages after PTCA with anti-fibronectin, tenascin-C, collagens I and III, and PG-M/versican antibodies. Tenascin-C deposition transiently increased within 1 month after PTCA, when smooth muscle cell migration and proliferation was active. Following the disappearance of tenascin-C, PG-M/versican accumulation increased and peaked between 1 month and 3 months when clinical restenosis was most actively progressing. At later stages, the PG-M/versican was replaced by a more mature ECM consisting of collagens I and III. The volume ratio of elastin remained at a low level throughout. Our results demonstrate that the matrix proteins of human restenotic lesions sequentially change after angioplasty and that tenascin-C could be a key molecule in the early stages.


Assuntos
Angioplastia Coronária com Balão , Vasos Coronários/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Oclusão de Enxerto Vascular/metabolismo , Tenascina/metabolismo , Túnica Íntima/metabolismo , Proteoglicanas de Sulfatos de Condroitina/metabolismo , Colágeno/metabolismo , Vasos Coronários/patologia , Feminino , Fibronectinas/metabolismo , Oclusão de Enxerto Vascular/patologia , Humanos , Imuno-Histoquímica , Lectinas Tipo C , Masculino , Pessoa de Meia-Idade , Túnica Íntima/patologia , Versicanas
19.
Eur J Pharmacol ; 284(1-2): 25-33, 1995 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-8549633

RESUMO

In extracts of the human aorta, five isoenzymes of cyclic nucleotide phosphodiesterase, namely, phosphodiesterase I, phosphodiesterase II, phosphodiesterase III, phosphodiesterase IV and phosphodiesterase V, were identified exclusively in the cytosolic fraction, and no phosphodiesterase activity was detected in the particulate fraction. Phosphodiesterase V and phosphodiesterase I were the major cGMP-hydrolyzing enzymes in the human aorta. A novel vasorelaxant, sodium 1-[6-chloro-4-(3,4-methylenedioxybenzyl)aminoquinazolin-2-yl ]piperidine-4- carboxylate sesquihydrate (E4021), relaxed prostaglandin F2 alpha-precontracted strips of human pulmonary artery with an ED50 value of 0.5 microM. E4021 potently and highly selectively inhibited the activity of phosphodiesterase V from human aorta with a Ki value of 2.4 nM. These results suggest that there is a unique distribution of phosphodiesterase isoenzymes in the human aorta and that inhibitors of phosphodiesterase V might be useful as a new type of vasodilator in the treatment of clinical disorders.


Assuntos
3',5'-GMP Cíclico Fosfodiesterases/metabolismo , Isoenzimas/metabolismo , Músculo Liso Vascular/enzimologia , Inibidores de Fosfodiesterase/farmacologia , Piperidinas/farmacologia , Quinazolinas/farmacologia , Vasodilatadores/farmacologia , 3',5'-GMP Cíclico Fosfodiesterases/antagonistas & inibidores , 3',5'-GMP Cíclico Fosfodiesterases/isolamento & purificação , Aorta/efeitos dos fármacos , Aorta/enzimologia , Proteínas Quinases Dependentes de Cálcio-Calmodulina/isolamento & purificação , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Citosol/enzimologia , Dinoprosta/farmacologia , Humanos , Técnicas In Vitro , Isoenzimas/antagonistas & inibidores , Isoenzimas/isolamento & purificação , Rim/efeitos dos fármacos , Rim/enzimologia , Cinética , Contração Muscular/fisiologia , Relaxamento Muscular/efeitos dos fármacos , Frações Subcelulares/enzimologia
20.
Eur J Pharmacol ; 376(3): 315-20, 1999 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-10448893

RESUMO

It is well known that inhibition of myosin phosphatase induces smooth muscle contraction in the absence of Ca2+. We characterized the kinase(s) which plays a role in Ca2+-independent, microcystin-LR-induced contraction in permeabilized smooth muscle of the rabbit portal vein. Assessments of various protein kinase inhibitors revealed this kinase(s) (1) was sensitive to staurosporine (1 microM), but resistant to other agents including wortmannin (10 microM), Y-27632 ((R)-(+)-trans-N-(4-pyridyl)-4-(1-aminoethyl)-cyclohexanecarboxamide+ ++, 100 microM). HA1077 (1-(5-isoquinolinylsulfonyl)-homopiperazine, 100 microM), H-7 (1-(5-isoquinolinylsulfonyl)-2-methylpiperazine, 100 microM), and calphostin C (100 microM), and (2) induced phosphorylation of 20 kDa myosin light chain at serine-19. We concluded that other kinases exist which phosphorylate myosin light chain at serine-19 and induce Ca2+-independent smooth muscle contraction, distinct from Rho-associated kinase, myosin light chain kinase, and protein kinase C.


Assuntos
Amidas/farmacologia , Inibidores Enzimáticos/farmacologia , Contração Muscular/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Quinase de Cadeia Leve de Miosina/efeitos dos fármacos , Piridinas/farmacologia , Fator Rho/efeitos dos fármacos , Animais , Masculino , Microcistinas , Contração Muscular/fisiologia , Músculo Liso Vascular/fisiologia , Quinase de Cadeia Leve de Miosina/metabolismo , Peptídeos Cíclicos/farmacologia , Fosforilação/efeitos dos fármacos , Coelhos , Fator Rho/metabolismo , Estaurosporina/fisiologia , Vasoconstritores/farmacologia
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