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51.
Summary We investigated the changes in the content of L-ascorbic acid (L-AA), glucose, fructose, surose and total glycoalkaloids (TGA)
during storage of potatoes, cv. Bintje, for 12 weeks at 7,16 and 28°C. The initial amount of L-AA was 8.2 mg/100g fresh weight;
after 12 weeks' storage at 7°C it had decreased, while at 16 and 28°C it had increased. The sugar content went up most in
potatoes stored at 28°C, but remained below the level at which potatoes taste sweet. The sugar content rose slightly at 16°C,
while it decreased in tubers stored at 7°C. The initial TGA content, in equivalent amounts of α-solanine, was 3.6 mg/100 g
fresh weight; after 12 weeks' storage it had decreased slightly at all three storage temperatures. 相似文献
52.
53.
Daniel Rodrigues Celso Alves André Horta Susete Pinteus Joana Silva Gérald Culioli Olivier P. Thomas Rui Pedrosa 《Marine drugs》2015,13(2):713-726
Cancer and infectious diseases continue to be a major public health problem, and new drugs are necessary. As marine organisms are well known to provide a wide range of original compounds, the aim of this study was to investigate the bioactivity of the main constituents of the cosmopolitan red alga, Sphaerococcus coronopifolius. The structure of several bromoditerpenes was determined by extensive spectroscopic analysis and comparison with literature data. Five molecules were isolated and characterized which include a new brominated diterpene belonging to the rare dactylomelane family and named sphaerodactylomelol (1), along with four already known sphaerane bromoditerpenes (2–5). Antitumor activity was assessed by cytotoxicity and anti-proliferative assays on an in vitro model of human hepatocellular carcinoma (HepG-2 cells). Antimicrobial activity was evaluated against four pathogenic microorganisms: Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Candida albicans. Compound 4 exhibited the highest antimicrobial activity against S. aureus (IC50 6.35 µM) and compound 5 the highest anti-proliferative activity on HepG-2 cells (IC50 42.9 µM). The new diterpene, sphaerodactylomelol (1), induced inhibition of cell proliferation (IC50 280 µM) and cytotoxicity (IC50 720 µM) on HepG-2 cells and showed antimicrobial activity against S. aureus (IC50 96.3 µM). 相似文献
54.
Garcia JL Navarro IT Biazzono L Freire RL da Silva Guimarães Junior J Cryssafidis AL Bugni FM da Cunha IA Hamada FN Dias RC 《Veterinary parasitology》2007,145(3-4):197-206
This study evaluated a vaccine made from crude rhoptry proteins of Toxoplasma gondii with Quil-A, which was administered to cats by the intranasal route. Eleven short-hair domestic cats were divided into four groups: G1 (n=3) received three doses (200 microg/dose) of the rhoptry vaccine with Quil-A (20 microg); G2 (n=3) received PBS with Quil-A (20 microg); G3 (n=3) and G4 (n=2) received only PBS. Treatments were administered at days 0, 21, and 42 by the intranasal route. Challenge was done to G1, G2, and G3 animals with 600 cysts of the VEG strain on day 51 (challenge day); G4 animals were unchallenged. The anti-T. gondii IgG and IgA antibody levels from sera were measured by indirect enzyme-linked immunosorbent assay (ELISA). At challenge, two animals from G1 revealed antibody levels for both IgG and IgA; oocysts were not detected in feces of these two cats. There were no differences in hematological values between groups throughout the experiment (p>0.10). Preventable fractions were 67% in G1 and 0% in G2 and G3. Comparatively, G1 animals shed 89.3% and 90.8% less oocysts than G3 and G4, respectively. Two out of three cats were protected against T. gondii oocyst shedding when the rhoptry vaccine was administered by the intranasal route. This is the first study using crude rhoptry proteins as vaccine by the intranasal route in cats to evaluate protection against oocysts shedding. 相似文献
55.
Shayne P. Bisetto Adriano B. Carregaro André E.S. Nicolai Thais F. Bressan William P. Leal Nathalia V. Xavier Diego F. Leal André F.C. Andrade 《Veterinary anaesthesia and analgesia》2017,44(3):594-599
Objective
To evaluate the effect of hyaluronidase on uptake, duration and speed of elimination of xylazine–tiletamine–zolazepam administered in the subcutaneous fat over the dorsal lumbar region of swine.Study design
Blinded, randomized, crossover study.Animals
Six healthy Landrace/Large White pigs weighing 132 ± 24 kg (mean ± standard deviation).Methods
Animals were administered xylazine (1 mg kg?1) and tiletamine–zolazepam (8 mg kg?1) (control treatment, CON), or xylazine–tiletamine–zolazepam at the same doses with hyaluronidase (400 IU) (treatment HYA). The treatments were administered into the dorsal lumbar adipose tissue, 2.5–3.0 cm laterally from the spinous process of the second lumbar vertebra. The latency, anesthesia and recovery periods were measured. Heart rate, noninvasive systolic, diastolic, and mean arterial pressures, respiratory rate, hemoglobin oxygen saturation and rectal temperature were recorded every 10 minutes for up to 50 minutes.Results
One animal in CON and one animal in HYA were responsive to stimulation and did not allow safe handling. No significant difference was found between treatments for latency (CON 11.3 ± 5.9 minutes, HYA 7.4 ± 5.1 minutes) and anesthesia (CON 53 ± 53 minutes, HYA 49 ± 38 minutes) periods. Recovery period was shorter in HYA (9 ± 6 minutes) than in CON (32 ± 16 minutes) (p < 0.05). Physiological variables were not significantly changed over time and were within accepted normal clinical limits for the species in both treatments.Conclusion and clinical relevance
Hyaluronidase (400 IU) administered into adipose tissue in pigs did not reduce the latency and duration of dissociative anesthesia, but was associated with faster recovery. 相似文献56.
Véronique Bernier Gosselin David Francoz Marie Babkine André Desrochers Sylvain Nichols Elizabeth Doré Christian Bédard Joane Parent Julie-Hélène Fairbrother Gilles Fecteau 《The Canadian veterinary journal. La revue veterinaire canadienne》2012,53(9):957-962
Epidemiological data, clinical findings, laboratory data, medical imaging, and outcomes were reviewed in 29 dairy calves with otitis media/interna. Age at admission ranged from 1 to 24 wk. The majority of calves were referred during winter. Clinical signs included drooping ear, ptosis, head tilt, abnormal nystagmus, strabismus, dysphagia, regurgitation, stiff neck, opisthotonos, facial hyperesthesia, and purulent aural discharge. Intranasal endoscopic examination of 5 animals revealed nasopharyngeal collapse in 4. Cerebrospinal fluid (CSF) was abnormal in all of 7 cases. Mycoplasma bovis was cultured from all but 1 case with external ear or tympanic bullae samples (n = 12), and Mycoplasma arginini was cultured from the remaining ear sample. Radiographs of the tympanic bullae were performed in 24 calves, tomodensitometry (CT) in 3 calves and ultrasound in 4 calves. According to medical imaging techniques or necropsy, 69% of the cases were classified as chronic. Mean duration of treatment was 23.3 d. The rate of clinical recovery was 75%. 相似文献
57.
João H Perotta Paulo A Canola Maristela CS Lopes Patrícia M Évora Paulo EB Martinez André Escobar Carlos AA Valadão 《Veterinary anaesthesia and analgesia》2014,41(4):357-364
ObjectiveTo evaluate the effects of intravenous (IV) or intramuscular (IM) hyoscine premedication on physiologic variables following IV administration of medetomidine in horses.Study designRandomized, crossover experimental study.AnimalsEight healthy crossbred horses weighing 330 ± 39 kg and aged 7 ± 4 years.MethodsBaseline measurements of heart rate (HR), cardiac index (CI), respiratory rate, systemic vascular resistance (SVR), percentage of patients with second degree atrioventricular (2oAV) block, mean arterial pressure (MAP), pH, and arterial partial pressures of carbon dioxide (PaCO2) and oxygen (PaO2) were obtained 5 minutes before administration of IV hyoscine (0.14 mg kg?1; group HIV), IM hyoscine (0.3 mg kg?1; group HIM), or an equal volume of physiologic saline IV (group C). Five minutes later, medetomidine (7.5 μg kg?1) was administered IV and measurements were recorded at various time points for 130 minutes.ResultsMedetomidine induced bradycardia, 2oAV blocks and increased SVR immediately after administration, without significant changes in CI or MAP in C. Hyoscine administration induced tachycardia and hypertension, and decreased the percentage of 2oAV blocks induced by medetomidine. Peak HR and MAP were higher in HIV than HIM at 88 ± 18 beats minute?1 and 241 ± 37 mmHg versus 65 ± 16 beats minute?1 and 192 ± 38 mmHg, respectively. CI was increased significantly in HIV (p ≤ 0.05). Respiratory rate decreased significantly in all groups during the recording period. pH, PaCO2 and PaO2 were not significantly changed by administration of medetomidine with or without hyoscine.Conclusion and clinical relevanceHyoscine administered IV or IM before medetomidine in horses resulted in tachycardia and hypertension under the conditions of this study. The significance of these changes, and responses to other dose rates, requires further investigation. 相似文献
58.
59.
Barrera-García VD Gougeon RD Di Majo D De Aguirre C Voilley A Chassagne D 《Journal of agricultural and food chemistry》2007,55(17):7021-7027
The evolution of polyphenols of enological interest- monomeric anthocyanins, (+)-catechin, (-)-epicatechin, gallic acid, and trans-resveratrol-in the presence of oak wood was investigated in aging-model conditions. Disappearance kinetics showed that, except for gallic acid, all of the wine polyphenols tend to disappear from the model wine in presence of oak wood, to reach an equilibrium after 20 days of contact. At equilibrium, the higher disappearance rates were obtained for monomeric anthocyanins and trans-resveratrol with values of 20 and 50%, respectively. For monomeric anthocyanins, the rate of disappearance seemed to be independent of their nature. In order to evaluate the contribution of sorption to oak wood in the disappearance phenomena, sorption kinetics were determined for trans-resveratrol and malvidin-3-glucoside through the extraction and the quantification of the fraction sorbed to wood. These curves showed that the wood intake of trans-resveratrol and malvidin-3-glucoside followed a two-step behavior, with a higher rate during the first 2 days, likely due to a surface sorption mechanism, and then a slower rate to reach the equilibrium, which could be related to a diffusion mechanism. The comparison of disappeared and sorbed amounts at equilibrium showed that a minor part of the disappeared monomeric anthocyanins were sorbed by wood. In contrast, half of the concentration decrease of trans-resveratrol in wine finds its origin in a sorption mechanism by oak wood. Results in real wine show similar sorption kinetics. 相似文献
60.
Alexandre Barbosa Reis Andréa Teixeira-Carvalho Rodolfo Cordeiro Giunchetti Bruno Mendes Roatt Wendel Coura-Vital Roney de Carvalho Nicolato Denise Silveira-Lemos Rodrigo Corrêa-Oliveira Olindo de Assis Martins-Filho 《Veterinary immunology and immunopathology》2014,157(3-4):190-196
To determine the role of the spleen in the pathogenesis of canine visceral leishmaniasis (CVL), we analyzed cellular immunophenotypic profiles of 52 dogs naturally infected with Leishmania infantum, clinically classified as follows: asymptomatic dogs-I (AD-I), seronegative/PCR+; asymptomatic dogs-II (AD-II), seropositive/PCR+; oligosymptomatic dogs (OD) and symptomatic dogs (SD). Seven non-infected dogs (CD) were included as a control group. AD-II presented higher levels of CD8+ T splenocytes and lower TCD4+/TCD8+ ratio in comparison with CD. OD and SD showed lower percentages of CD21+ as compared with AD-II. All seropositive dogs presented lower levels of CD45RA+ than CD. Regardless of the stimuli used, the proliferation index from splenocytes in vitro was inversely correlated with clinical status. After LSA stimulation, there was a higher percentage of specific CD8+ T in AD-II than CD and non-stimulated culture. In contrast, splenocytes from SD under in vitro LSA stimulation induced decreased MHC-II+ expression in comparison with all groups, and non-stimulated culture. In conclusion, the role of CD8+ T splenocytes seems to be important for an effective immunological response, a hallmark of asymptomatic CVL, whereas the pronounced loss of MHC-II expression upon LSA stimulation is a biomarker of symptomatic CVL. 相似文献