Translational and rotational motions of albumin sensed by a non-covalent associated porphyrin under physiological and acidic conditions: a fluorescence correlation spectroscopy and time resolved anisotropy study.

The interaction between a free-base, anionic water-soluble porphyrin, TSPP, and the drug carrier protein, bovine serum albumin (BSA) has been studied by time-resolved fluorescence anisotropy (TRFA) and fluorescence correlation spectroscopy (FCS) at two different pH-values. Both rotational correlation times and translational diffusion times of the fluorescent species indicate that TSPP binding to albumin induces very little conformational changes in the protein under physiological conditions. By contrast, at low pH, a bi-exponential decay is obtained where a short rotational correlation time (¿ int¿=¿1.2 ns) is obtained, which is likely associated to wobbling movement of the porphyrin in the protein binding site. These physical changes are corroborated by circular dichroism (CD) data which show a 37% loss in the protein helicity upon acidification of the medium. In the presence of excess porphyrin formation of porphyrin J-aggregates is induced, which can be detected by time-resolved fluorescence with short characteristic times. This is also reflected in FCS data by an increase in molecular brightness together with a decrease in the number of fluorescent molecules passing through the detection volume of the sampl

Effects of bovine somatotrophin (bST) on ovarian function in post-partum beef cows

Full text not available. Only the abstract. DOI: 10.1071/RD9960951The effects of bovine somatotrophin (bST) on ovarian follicle development and function and associated gonadotrophin profiles during the first nine weeks post partum were investigated in beef cows. Thirty-two cows (Shorthorn x Galloway) in moderately low body condition (BC) at calving were fed to maintain BC thereafter. At Weeks 2, 4, 6 and 8 post partum, animals were injected with 320 mg bovine somatotrophin (bST) (T, treated; n = 17) or with the carrier oil only (C, control; n = 15). Ovulation occurred in 4 of 17 T cows and 0 of 15 C cows (P = 0.10) by nine week post partum. Treatment with bST did not affect the numbers of small (3-8 mm in diameter) or large (> 8 mm in diameter) follicles or the granulosa cell populations but enhanced the oestradiol (P < 0.05) and insulin-like growth factor-I (IGF-I) content (P < 0.01) of large follicles by nine weeks post partum. It did not significantly affect the testosterone concentrations of large follicles. Circulating concentrations of growth hormone (GH) and IGF-I were higher in T cows than in C cows (P < 0.001) but were unrelated to gonadotrophin profiles or gonadotrophin receptor concentrations in the follicles. At Week 8, plasma insulin concentrations were higher in T cows than in C cows both before (P < 0.05) and after (P < 0.05) glucose injection. It is concluded that GH may play an important role in mediating the effects of nutritional state on ovarian function during the post-partum period, possibly through alteration of intrafollicular IGF-I concentrations

Effects of quercetin on exercise performance, physical activity and blood supply in a novel model of sustained hind-limb ischaemia

Background: There are currently few effective drugs to treat the leg symptoms of peripheral arterial disease (PAD). Previous studies have suggested that the nutraceutical, quercetin, can improve exercise performance and reduce pain sensitivity in healthy mice and improve blood supply in a rodent model of acute hind-limb ischaemia. These models may not be relevant to people with PAD. The aim of this study was to examine the effect of quercetin on exercise performance, physical activity and blood supply in a novel mouse model of sustained hind-limb ischaemia. Methods: Hind-limb ischaemia was induced in 6-month-old male apolipoprotein E-deficient mice using a novel two-stage surgical procedure. Five days after induction of ischaemia, mice were allocated to commence dietary quercetin or a control diet for 4 weeks. The primary outcome was exercise performance evaluated using a treadmill test. Other outcomes included physical activity, estimated by an open field test, and hind-limb blood supply, assessed by laser Doppler monitoring. Results: A sustained reduction in relative limb blood supply (P < 0.001) was achieved consistently in all 48 mice before allocation to a control (n = 24) or quercetin (n = 24) diet. Quercetin did not improve exercise performance (P = 0.785), physical activity (P = 0.151) or relative limb blood supply (P = 0.954) over the 4-week assessment period. Conclusion: These data suggest that quercetin does not improve exercise performance, physical activity or limb blood supply in mice with sustained hind-limb ischaemia, and therefore is unlikely be an effective treatment for PAD

Caracterização da condição física e fatores de risco cardiovascular de policiais militares rodoviários

ResumoObjetivoO objetivo do presente estudo foi verificar os níveis de condição, composição corporal e pressão arterial de policiais rodoviários do estado do Paraná - Brasil.MétodoFizeram parte da amostra 52 oficiais do sexo masculino (idade: 38,3±6,3 anos, massa corporal: 89,6±18,4kg) de diferentes patentes. Foram realizadas diversas mensurações para obtenção do índice de massa corporal (IMC), circunferência de cintura (CC), relação cintura/quadril (RCQ), composição corporal por meio da espessura de dobras cutâneas, potência aeróbia estimada indiretamente em teste de esforço ergométrico, resistência muscular localizada (RML) de membros superiores e abdominal e os níveis pressóricos foram aferidos por método auscultatório.ResultadosConsiderando as variáveis analisadas, os policiais rodoviários apresentaram IMC de 28,6±4,8kg/m2, risco cardiovascular elevado (95,4±10,8cm) para CC e alto (0,92±0,05) para RCQ. O percentual de gordura corporal apresentou-se acima dos valores recomendáveis (23,6±4,3 %) para saúde, a potência aeróbia estimada foi considerada boa (34,8±1,1ml/kg/min), a RML de membros superiores (21±8 repetições) e foi obtida por realização dos testes de abdominal e flexão de braço, respectivamente (28±8 repetições) foram classificadas como média e uma parcela importante dos oficiais (23 %) mostraram-se com níveis pressóricos elevados.ConclusãoOs policiais militares rodoviários mostraram-se com níveis inadequados de condição física, apresentando excesso de peso e adiposidade corporais, e, uma parcela importante, exibiu níveis pressóricos elevados, sugerindo elevado risco cardiovascular.AbstractObjectiveThe aim of this study was to assess the physical fitness, body composition and blood pressure of highway police officers in the state of Paraná, Brazil.MethodThe sample consisted of 52 male (38.3±6.3 years old, 89.6±18.4kg) where the following determinations were performed: body mass index (BMI); waist circumference (WC); waist/hip ratio (WHR); body composition (skinfold thickness); aerobic power (indirectly estimated in a treadmill test); muscle strength of the upper limbs was measured by the number of push-ups and abdominal strength by the number of crunches (ES) and blood pressure (measured by auscultatory method).ResultsThe highway police officers had a BMI classified as mild obesity (28.6±4.8kg/m2), and a higher cardiovascular risk as determined by WC (95.4±10.8cm) and WHR (0.92±0.05). The percentage of body fat was above the recommended values (23.6±4.3 %) but the aerobic power was considered good (34.8±1.1ml/kg/min). Mean ES upper body (21±8 repetitions) and abdomen (28±8 repetitions) were qualified as fair but mean blood pressure was considered high in 23 % of the police officers.ConclusionBased on our results it was possible to conclude that although the police officers presented good levels of aerobic power and muscle strength, they are overweight and showed a higher cardiovascular risk