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71.
The pharmacokinetic (PK) parameters of artesunate, artemether and their metabolites dihydroartemisinin (DHA) and dihydroartemisinin-glucuronide (DHA-glucuronide) were determined in sheep naturally infected with Fasciola hepatica. Sheep were treated either with artesunate (intramuscular (i.m.): 40 and 60 mg/kg) or artemether (i.m.: 40 and 160 mg/kg; oral: 80 mg/kg). Blood samples were withdrawn at selected time points post treatment and the artemisinins were quantified in plasma by liquid chromatography and tandem mass spectrometry (LC-MS/MS). The in vitro effect of the metabolites against F. hepatica was investigated using a phenotype-based assay and scanning electron microscopy (SEM). Following artesunate applications (40 and 60 mg/kg), comparable C(max) (maximal plasma concentration) and AUCs (area under the plasma concentration-time curve) were observed for artesunate (C(max): 8.4×10(3) and 9.4×10(3)ng/ml; AUC: 6.9×10(5) and 9.7×10(5) ng min/ml), DHA (C(max): both 2.4×10(3)ng/ml; AUC: 3.7×10(5) and 5.0×10(5) ng min/ml), and DHA-glucuronide (C(max): 1.7×10(4) and 1.6×10(4)ng/ml; AUC: 2.6×10(6) and 3.3×10(6) ng min/ml). Mean elimination half-lifes (t(1/2)) of artesunate, DHA and DHA-glucuronide ranged between 58 and 63 min, 94 and 113min, and 89 and 98 min, respectively. The i.m. oil-based drug formulation liberated artemether slowly and constant levels of artemether and its metabolites were observed during the entire sampling period (24 h). The AUCs of all analytes were significantly higher for the i.m. 160 mg/kg dose compared to i.m. 40 and oral 80 mg/kg doses (P=0.018). Mean C(max) of artemether (2126 and 426 ng/ml) and DHA-glucuronide (3477 and 1587 ng/ml) were higher following oral compared to i.m. (160 mg/kg) treatments (P>0.068), whereas C(max) of DHA was significantly higher following i.m. applications (P=0.0062). DHA rapidly reduced the viability of F. hepatica in vitro, whereas DHA-glucuronide showed no activity. SEM observations revealed only minor and focal tegumental alterations in few of the DHA treated worms. The calculated PK parameters reflect the anthelmintic activity of artesunate and artemether following different routes of application and will aid in the design of future studies with these drugs.  相似文献   
72.
73.
Marrubium vulgare (Lamiaceae) is a plant traditionally used for the treatment of diabetes in Algeria. Compositional analysis of the aqueous infusion revealed the presence of fifteen metabolites, all belonging to the class of polyphenols. Particularly, seven flavonoids have been detected, together with 5-caffeoylquinic (chlorogenic) acid in small amounts; the extract is dominated by the presence of a series of complex molecules, characterized as verbascoside (acteoside) derivatives. Concerning the anti-diabetic effectiveness a series of in vivo experiments were carried out on albinos Wistar rats. Diabetes was induced in the animals by intra-peritoneal injection of alloxane; they were treated twice a day with aqueous extract from aerial part infusion (100, 200 and 300 mg/kg body weight) and glibenclamide (5mg/kg body weight) for 15 days. Oral administration of 200 and 300 mg/kg body weight of aqueous extract the Marrubium vulgare induced an significant effect antidiabetic and antihyperlipidemic (dose-dependent effect). A decrease in blood glucose by 50% for the dose 100 mg/kg and more than 60% for doses 200 and 300 mg/kg, as well as a significant lowering of total lipids, triglycerides, and total cholesterol levels in treated animals, compared with diabetic controls group (p<0.001), have been observed. Glibenclamide was used as reference and showed similar effects.  相似文献   
74.
The association of cryptorchidism, functional Sertoli cell tumors, and spermatic cord torsion has been rarely reported in the literature. Two dogs were admitted for bilateral skin alopecia and weight loss. Both animals were cryptorchid and displayed a pendulous preputial sheath, prostate hypertrophy, and increased levels of circulating oestrogen. Transabdominal palpation and ultrasonography revealed the presence of neoplastic retained gonads. During surgery, spermatic cord torsion was also detected in the enlarged neoplastic testes of both dogs. Histologic examination confirmed the presence of Sertoli cell tumors that were primarily responsible for the feminizing syndrome. Complete remission of all symptoms occurred within 3 months after orchiectomy.  相似文献   
75.
The activity rhythm can be entrained by nonphotic cues, especially food availability. Daily feeding schedules can act as “Zeitgeber” to synchronize the circadian system. In this study, the authors evaluated the influence of different feeding schedules on the daily rhythm of total locomotor activity in ponies. Six clinically healthy Shetland ponies were kept under natural 12/12-h light/dark cycle and monitored during 4 different feeding schedules: fed twice (at 8 am and 8 pm), fasted, fed at 8 pm, fed at 8 am, and fed twice a day again. Water was available ad libitum. To record total activity, we equipped the animals with actigraphy-based data loggers (Actiwatch-Mini). Two-way analysis of variance revealed a significant main effect of the time of day and no effect of feeding schedules on the amount of total locomotor activity. Locomotor activity showed daily rhythmicity in all experimental conditions, with diurnal acrophase. The amplitude of the rhythms and their robustness statistically changed across all experimental conditions. Our findings support the theory that when given essentially free choice hay, the time of feeding did not entrain activity, and suggest that feeding behavior can influence the distribution of locomotor activity during a 24-hour period in ponies, with changes in the amplitude and robustness of the rhythm.  相似文献   
76.
Pseudomonas aeruginosa represents an opportunistic pathogen for animals and humans that is often associated with high disease morbidity and, at times, mortality. Captive reptiles have been shown to be reservoirs of P. aeruginosa strains that can be sources of exposure to humans that come in contact with these animals. In this study, the prevalence of P. aeruginosa among subclinical captive reptile species and the antimicrobial sensitivity of bacterial isolates were investigated. Sixty-five oral swabs were collected from captive reptiles belonging to 15 different species in which no overt signs of disease were evident. From this group of animals, 46 (70.8%) isolates were identified as P. aeruginosa. All of the P. aeruginosa strains were shown to have a wide range of antibiotic resistance. At present, there is a paucity of data regarding the prevalence of P. aeruginosa in various reptile species; therefore, continued scientific investigations are indicated to determine the significance of P. aeruginosa infection as it relates to captive reptile species.  相似文献   
77.
Growth, weight at birth and daily weight gain (DWG) on 12 water buffalo calves, starting from 6 days of age until completion of weaning, was investigated in this study. Different feeding regimens were given to two groups of animals with regard to daily milk replacer: (1) group 1 (G1) received a double concentration in single administration; whereas (2) group 2 (G2) received the same amount of milk replacer split twice daily. Blood samples were collected from each calf on days 6, 30, 60 and 90 to evaluate acute phase proteins (haptoglobin), bactericide activity, lysozime, total protein content and biochemical parameters. No differences were observed between the two groups in terms of dry matter intake, feed efficiency and live body weight at the end of the study. Interestingly, a significantly (P?<?0.05) reduced DWG was observed earlier in G1 (day 45) than in G2 (day 60). Gastrointestinal disorders were not recorded throughout the experimental period, and no significant differences were recorded between the two groups for all considered parameters. This study confirms the possibility of utilising one daily administration of milk replacer in water buffalo calf during weaning. This new approach facilitates calves management, without interfering with calves growing performances.  相似文献   
78.
A case of pulmonary carcinoma in a 23-year-old Quarterhorse mare is described. On physical examination, depression, poor body condition, tachypnea, bilateral serosanguineous nasal discharge and a wide area of reduced breath sounds in association with the right hemithorax were detected. Laboratory evaluation showed leukocytosis with neutrophilia and lymphopenia, hyperfibrinogenemia, hyperprotidemia, hypoalbuminemia, increased beta 2 and gamma globulin fractions, hypoxemia, and normocapnia. Radiography and thoracic ultrasonography revealed a large rounded mass extending from the 9th to the 14th right intercostal space, where neither bronchial nor vascular structures were detectable. Endoscopy showed a large amount of serosanguineous fluid within the tracheal lumen and a mass of reddish soft tissue completely obliterating the right caudal lobar bronchus. Histopathology of the endobronchial mass and of the transthoracic ultrasound-guided biopsy samples was consistent with a primary pulmonary epithelial tumor. Due to worsening of the clinical condition, the mare was euthanized. Postmortem examination confirmed the presence of a large 30-cm mass located in the right caudal pulmonary lobe, characterized by epithelial cells arranged in papillary projections and alveolar structures, findings consistent with bronchioloalveolar carcinoma.  相似文献   
79.
Serum protein electrophoresis (SPE) is a technique that could be considered one of the most useful diagnostic aids available to the clinician. The effect of storage time and temperature on the total proteins and electrophoretic fractions (albumin, α1-, α2-, β1-, β2-, and γ-globulins) was assessed in 24 healthy horses. All samples, collected by jugular vein puncture, were centrifuged and divided into 4 aliquots. The 1st aliquot was analyzed within 3 h from collection (time 0), the 2nd was refrigerated at +4°C for 24 h, the 3rd was refrigerated at +4°C for 48 h, and the last was frozen at −20°C for 48 h. One-way repeated-measures analysis of variance (ANOVA) showed a significant effect (P < 0.05) of the different storage conditions on the concentrations of all the parameters studied and significant variations in the percentages of albumin, α1-globulins, α2-globulins, and γ-globulins. Compared with time 0 the total protein concentration increased significantly after 48 h at −20°C, the albumin percentage decreased after 48 h at −20°C, the α1-globulin percentage increased after 24 h at +4°C, the α2-globulin percentage increased after 48 h at +4°C and at −20°C, and the γ-globulin percentage increased after 48 h at −20°C. The results should help veterinary practitioners handle and store equine serum samples appropriately. Further investigations at different storage times and temperatures could be useful.  相似文献   
80.
An in-depth study of the secondary metabolites contained in the Caribbean sponge Smenospongia aurea led to the isolation of smenamide A (1) and B (2), hybrid peptide/polyketide compounds containing a dolapyrrolidinone unit. Their structures were elucidated using high-resolution ESI-MS/MS and homo- and heteronuclear 2D NMR experiments. Structures of smenamides suggested that they are products of the cyanobacterial metabolism, and 16S rRNA metagenomic analysis detected Synechococcus spongiarum as the only cyanobacterium present in S. aurea. Smenamides showed potent cytotoxic activity at nanomolar levels on lung cancer Calu-1 cells, which for compound 1 is exerted through a clear pro-apoptotic mechanism. This makes smenamides promising leads for antitumor drug design.  相似文献   
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