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1.
Public Health ; 158: 37-46, 2018 May.
Article in English | MEDLINE | ID: mdl-29544174

ABSTRACT

OBJECTIVES: The majority of adolescent girls fail to meet public health guidelines for physical activity. Engaging mothers in the promotion of physical activity for their daughters may be an important strategy to facilitate behaviour change. The aim of this study was to use the behaviour change wheel (BCW) framework to design the components of an intervention to improve adolescent girls' physical activity. STUDY DESIGN: Cross-sectional study to inform intervention development. METHODS: The BCW framework was used to (1) understand the behaviour, (2) identify intervention functions and (3) select content and implementation options. A circular development process was undertaken by the research team to collectively design the intervention in accordance with the steps recommended by the BCW. RESULTS: The BCW design process resulted in the selection of six intervention functions (education, persuasion, incentivization, training, modelling, enablement) and 18 behaviour change techniques delivered via group-based, face-to-face mode. Behaviour change technique groupings include: goals and planning; feedback and monitoring; social support; shaping knowledge; natural consequences; comparison of behaviour; associations; comparison of outcomes; reward and threat; identity; and, self-belief. CONCLUSIONS: The BCW process allowed an in-depth consideration of the target behaviours and provided a systematic framework for developing the intervention. The feasibility and preliminary efficacy of the programme will be examined.


Subject(s)
Adolescent Behavior/psychology , Exercise/psychology , Health Promotion/methods , Mother-Child Relations/psychology , Adolescent , Cross-Sectional Studies , Female , Humans , Mothers/psychology , Nuclear Family/psychology , Parenting/psychology , Walking/psychology
2.
J Invertebr Pathol ; 115: 41-7, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24211424

ABSTRACT

In this study, we assessed the effect of the saprobic fungus, Fusarium oxysporum (Ascomycota: Hypocreales) on the fitness of the entomopathogenic nematode Heterorhabditis sonorensis (Caborca strain). Sand column assays were considered to evaluate the effect of fungal mycelia on infective juvenile (IJ) movement and host access. Additionally, we investigated the effect of fungal spores on the nematodes' ability to search for a host, its virulence, penetration efficiency and reproduction. Three application timings were considered to assess interactions between the fungus and the nematodes. In vitro assays were also considered to determine the effect of fungal extracts on the nematode's symbiotic bacteria. Our observations indicate that presence and age of fungal mycelia significantly affect IJ movement in the sand columns and their ability to establish in the host. These results were also reflected in a reduced insect mortality. In particular, treatments with the 15 days old mycelia showed a significant reduction in insect mortality and penetration efficiency. Presence of fungal spores also impacted nematode virulence and reproduction. In particular, two of the application timings tested (simultaneous [EPN and fungal spores applied at the same time] and alternate I [EPN applied first, fungus applied 24h later]) resulted in antagonistic interactions. Moreover, IJ progeny was reduced to half in the simultaneous application. In vitro assays revealed that fungal extracts at the highest concentration tested (10mg/ml) inhibited the growth of the symbiotic bacteria. Overall, these results suggest that saprobic fungi may play an important role in regulating. EPN populations in the soil, and that they may be one of the factors that impact nematode survival in the soil and their access to insect hosts.


Subject(s)
Host-Parasite Interactions/physiology , Hypocreales/physiology , Rhabditoidea/parasitology , Rhabditoidea/pathogenicity , Aging , Animals , Moths/parasitology , Soil Microbiology
3.
Diabetologia ; 55(12): 3369-81, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23001375

ABSTRACT

AIMS/HYPOTHESIS: Diabetic cardiomyopathy is characterised by diastolic dysfunction, oxidative stress, fibrosis, apoptosis and pathological cardiomyocyte hypertrophy. Phosphoinositide 3-kinase (PI3K)(p110α) is a cardioprotective kinase, but its role in the diabetic heart is unknown. The aim of this study was to assess whether PI3K(p110α) plays a critical role in the induction of diabetic cardiomyopathy, and whether increasing PI3K(p110α) activity in the heart can prevent the development of cardiac dysfunction in a setting of diabetes. METHODS: Type 1 diabetes was induced with streptozotocin in adult male cardiac-specific transgenic mice with increased PI3K(p110α) activity (constitutively active PI3K [p110α], caPI3K] or decreased PI3K(p110α) activity (dominant-negative PI3K [p110α], dnPI3K) and non-transgenic (Ntg) mice for 12 weeks. Cardiac function, histological and molecular analyses were performed. RESULTS: Diabetic Ntg mice displayed diastolic dysfunction and increased cardiomyocyte size, expression of atrial and B-type natriuretic peptides (Anp, Bnp), fibrosis and apoptosis, as well as increased superoxide generation and increased protein kinase C ß2 (PKCß2), p22 ( phox ) and apoptosis signal-regulating kinase 1 (Ask1) expression. Diabetic dnPI3K mice displayed an exaggerated cardiomyopathy phenotype compared with diabetic Ntg mice. In contrast, diabetic caPI3K mice were protected against diastolic dysfunction, pathological cardiomyocyte hypertrophy, fibrosis and apoptosis. Protection in diabetic caPI3K mice was associated with attenuation of left ventricular superoxide generation, attenuated Anp, Bnp, PKCß2, Ask1 and p22 ( phox ) expression, and elevated AKT. Further, in cardiomyocyte-like cells, increased PI3K(p110α) activity suppressed high glucose-induced superoxide generation and enhanced mitochondrial function. CONCLUSIONS/INTERPRETATION: These results demonstrate that reduced PI3K activity accelerates the development of diabetic cardiomyopathy, and that enhanced PI3K(p110α) activity can prevent adverse cardiac remodelling and dysfunction in a setting of diabetes.


Subject(s)
Class I Phosphatidylinositol 3-Kinases/metabolism , Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Type 1/metabolism , Diabetic Cardiomyopathies/metabolism , Diabetic Cardiomyopathies/prevention & control , Superoxides/metabolism , Animals , Blotting, Northern , Gene Expression Regulation , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Oxidative Stress
4.
Diabetologia ; 55(5): 1544-53, 2012 May.
Article in English | MEDLINE | ID: mdl-22374176

ABSTRACT

AIMS/HYPOTHESIS: An increase in the production of reactive oxygen species is commonly thought to contribute to the development of diabetic cardiomyopathy. This study aimed to assess whether administration of the antioxidant coenzyme Q(10) would protect the diabetic heart against dysfunction and remodelling, using the db/db mouse model of type 2 diabetes. Furthermore, we aimed to compare the efficacy of coenzyme Q(10) to that of the ACE inhibitor ramipril. METHODS: Six-week-old non-diabetic db/+ mice and diabetic db/db mice received either normal drinking water or water supplemented with coenzyme Q(10) for 10 weeks. Endpoint cardiac function was assessed by echocardiography and catheterisation. Ventricular tissue was collected for histology, gene expression and protein analysis. RESULTS: Untreated db/db diabetic mice exhibited hyperglycaemia, accompanied by diastolic dysfunction and adverse structural remodelling, including cardiomyocyte hypertrophy, myocardial fibrosis and increased apoptosis. Systemic lipid peroxidation and myocardial superoxide generation were also elevated in db/db mice. Coenzyme Q(10) and ramipril treatment reduced superoxide generation, ameliorated diastolic dysfunction and reduced cardiomyocyte hypertrophy and fibrosis in db/db mice. Phosphorylation of Akt, although depressed in untreated db/db mice, was restored with coenzyme Q(10) administration. We postulate that preservation of cardioprotective Akt signalling may be a mechanism by which coenzyme Q(10)-treated db/db mice are protected from pathological cardiac hypertrophy. CONCLUSIONS/INTERPRETATION: These data demonstrate that coenzyme Q(10) attenuates oxidative stress and left ventricular diastolic dysfunction and remodelling in the diabetic heart. Addition of coenzyme Q(10) to the current therapy used in diabetic patients with diastolic dysfunction warrants further investigation.


Subject(s)
Cardiomegaly/drug therapy , Diabetic Cardiomyopathies/drug therapy , Ubiquinone/analogs & derivatives , Vitamins/therapeutic use , Animals , Antihypertensive Agents/therapeutic use , Apoptosis/drug effects , Apoptosis/physiology , Cardiomegaly/diagnostic imaging , Cardiomegaly/metabolism , Cardiomegaly/physiopathology , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/metabolism , Diabetes Mellitus, Type 2/physiopathology , Diabetic Cardiomyopathies/diagnostic imaging , Diabetic Cardiomyopathies/metabolism , Diabetic Cardiomyopathies/physiopathology , Disease Models, Animal , Endomyocardial Fibrosis/drug therapy , Endomyocardial Fibrosis/etiology , Endomyocardial Fibrosis/metabolism , Female , Hyperglycemia/drug therapy , Hyperglycemia/metabolism , Lipid Peroxidation/drug effects , Lipid Peroxidation/physiology , Mice , Mice, Inbred C57BL , Oxidative Stress/drug effects , Oxidative Stress/physiology , Proto-Oncogene Proteins c-akt/metabolism , Ramipril/therapeutic use , Superoxides/antagonists & inhibitors , Superoxides/metabolism , Ubiquinone/therapeutic use , Ultrasonography , Ventricular Remodeling/drug effects , Ventricular Remodeling/physiology
5.
J Microsc ; 241(2): 119-24, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21118215

ABSTRACT

Many multiphoton imaging applications would benefit from a larger field of view; however, large field of views (>mm) require low magnification objectives which have low light collection efficiencies. We demonstrate a light collection system mounted on a low magnification objective that increases fluorescence collection by as much as 20-fold in scattering tissues. This peripheral detector results in an effective numerical aperture of collection >0.8 with a 3-4 mm field of view.


Subject(s)
Microscopy, Fluorescence/methods , Pathology/methods , Abdominal Neoplasms/pathology , Animals , Brain/cytology , Carcinoma/pathology , Mice , Spinal Cord/cytology
6.
Int J Pharm ; 252(1-2): 225-33, 2003 Feb 18.
Article in English | MEDLINE | ID: mdl-12550798

ABSTRACT

Carbamazepine microparticles were produced by the rapid expansion of supercritical carbon dioxide solutions (RESS) method. The characteristics of the resulting particles were studied by X-ray powder diffraction (XRPD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and image analysis. X-ray diffractograms and SEM photomicrographs revealed that the crystalline nature of the produced carbamazepine microparticles depended on operating pressure and temperature conditions. Different polymorphs were obtained under various operating conditions. Under certain temperature (below 40 degrees C) and pressure (below 240 bar) conditions, it was possible to form primarily the carbamazepine polymorph stipulated by US Pharmacopeia. A significant reduction was observed in the particle size and size distribution range of carbamazepine produced by RESS. The processed particles had a mean diameter smaller than 3 microm and a size distribution range between 0.5 and 2.5 microm compared to unprocessed starting material with a mean diameter of approximately 85 microm and a size distribution range between 15 and 336 microm. Thus, this study demonstrates that the polymorphic characteristics of carbamazepine microparticles produced by the RESS method can be controlled by varying operating pressure and temperature parameters.


Subject(s)
Carbamazepine/chemistry , Technology, Pharmaceutical/methods , Calorimetry, Differential Scanning/methods , Carbamazepine/analysis , Crystallization , Microscopy, Electron, Scanning , Particle Size , Stereoisomerism , Technology, Pharmaceutical/instrumentation
7.
Exp Physiol ; 86(1): 71-82, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11429622

ABSTRACT

Previous studies in fetal sheep have concluded that (a) the vascular AT(1) angiotensin II (Ang II) receptor subtype is present in the external umbilical artery, but not in other systemic blood vessels, and (b) carotid arterial rings contract in vitro in response to Ang II. These contractions are blocked by the AT(1) specific receptor antagonist losartan. The aim of the present study was to resolve the apparent contradiction of these earlier conclusions, by examining the distribution of Ang II receptor subtypes in different regions of the ovine fetal cardiovascular system, and to find out at what stage in development AT(1) receptors first appear. We measured AT(1) and AT(2) receptors in hearts, carotid arteries, aortae and umbilical vessels from fetal sheep aged 65-144 days (term approximately 150 days), and in hearts and aortae from lambs, and adult pregnant and non-pregnant ewes. Both AT(1) and AT(2) receptors were present in aortae of fetuses > 118 days gestation, and carotid arteries of fetuses > 121 days gestation, while in younger fetuses only AT(2) receptors were found. The proportion of carotid artery and aortic AT(1) receptors increased with age, while the proportion of AT(2) receptors decreased. The internal umbilical artery contained both subtypes, but there was no relationship between receptor density and gestational age. The external umbilical artery had only AT(1) receptors. The highest density of Ang II receptors was found in the fetal heart where the AT(2) subtype predominated. The density of fetal cardiac Ang II receptors declined with age (r = -0.44, P < 0.02) due to the decrease in the AT(2) subtype. The density in late gestation fetal hearts was greater than in lamb or adult hearts (P < 0.001). Our study shows that fetal systemic blood vessels contain AT(1) receptors, and we have documented for the first time that the appearance of AT(1) receptors is both different in different regions of the fetal cardiovascular system and is developmentally regulated. Together with the in vitro contractile studies, this suggests that Ang II can play an important role in fetal blood pressure regulation via AT(1) receptors in the fetal systemic vasculature, as well in the umbilicoplacental vessels. Experimental Physiology (2001) 86.1, 71-82.


Subject(s)
Blood Vessels/metabolism , Fetus/metabolism , Myocardium/metabolism , Pregnancy, Animal/metabolism , Receptors, Angiotensin/metabolism , Aging/metabolism , Animals , Aorta/embryology , Aorta/metabolism , Binding, Competitive , Blood Vessels/embryology , Cardiovascular System/embryology , Female , Gestational Age , Heart/embryology , Pregnancy , Protein Isoforms/metabolism , Receptor, Angiotensin, Type 1 , Receptor, Angiotensin, Type 2 , Sheep
8.
Regul Pept ; 99(2-3): 119-29, 2001 Jun 15.
Article in English | MEDLINE | ID: mdl-11384773

ABSTRACT

Previously, we showed that uterine arteries from late gestation pregnant ewes infused intravenously with angiotensin II (Ang II) for 24 h, displayed heightened responsiveness to Ang II in vitro. Furthermore, we found that a small population of ewes with a "preeclampsia-like" disorder also displayed this. Therefore, we have investigated the density and affinity of Ang II receptor subtypes in the uterine arteries from these groups. Ang II receptor binding was measured using 125I [Sar1Ile8] Ang II. Proportions of AT1 and AT2 receptors were determined by inhibiting 125I [Sar1Ile8] Ang II with losartan (AT1 antagonist) or PD 123319 (AT2 antagonist). Uterine arteries from 24-h Ang II-infused ewes had a lower proportion of AT2 receptors (56.2+/-2.3%) than control (saline-infused) ewes (84.1+/-1.0%; P<0.05). The density of AT2 receptors was reduced (P<0.05) while the density of AT1 receptors was not different. Thus, 24-h infusions of Ang II selectively down-regulated AT2 receptors in the uterine artery, resulting in heightened Ang II reactivity. By contrast, the binding properties of Ang II receptor subtypes in uterine arteries from ewes with the "preeclampsia-like" disorder were not different from control ewes.


Subject(s)
Angiotensin II/administration & dosage , Angiotensin II/metabolism , Angiotensin Receptor Antagonists , Down-Regulation , Receptors, Angiotensin/biosynthesis , Uterus/blood supply , Uterus/metabolism , Angiotensin II/blood , Animals , Catheterization , Down-Regulation/drug effects , Drug Administration Schedule , Female , Infusions, Intravenous , Pre-Eclampsia/blood , Pre-Eclampsia/metabolism , Pregnancy , Receptor, Angiotensin, Type 1 , Receptor, Angiotensin, Type 2 , Receptors, Angiotensin/blood , Renin/blood , Sheep , Uterus/drug effects
9.
Orthop Clin North Am ; 32(3): 527-38, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11888148

ABSTRACT

This framework for rehabilitation is consistent with the proximal-to-distal kinetic chain biomechanical model and applies current concepts of motor control and closed chain exercises. This framework approaches the final goal--glenohumeral motion and function-through facilitation by scapular control, and scapular control through facilitation by hip and trunk activation. This article supplies guidelines for rehabilitation and practices to implement the guidelines that have proved effective in our hands. Other protocols may be effective, as long as they adhere to several basic concepts of kinetic chain-based shoulder rehabilitation: 1. Functional shoulder rehabilitation requires that the muscle activations and joint motions follow a proximal-to-distal pathway along the appropriate kinetic chain. 2. Muscles around the shoulder function in an integrated fashion and should be rehabilitated in integrated patterns. Specific muscles may need isolated activation, but this activation should be facilitated by placing the proximal segments in a facilitating function. 3. Scapular control and coupled rotator cuff activation is vital to normal shoulder function. 4. Closed chain axial loading exercises are the primary means of early shoulder rehabilitation and are the mainstays of functional rehabilitation protocols.


Subject(s)
Athletic Injuries/rehabilitation , Exercise Therapy/methods , Joint Instability/rehabilitation , Practice Guidelines as Topic , Shoulder Injuries , Anthropometry , Athletic Injuries/diagnosis , Athletic Injuries/physiopathology , Biomechanical Phenomena , Clinical Protocols , Exercise Therapy/standards , Humans , Joint Instability/diagnosis , Joint Instability/physiopathology , Range of Motion, Articular , Recovery of Function , Time Factors , Wound Healing
10.
Eur J Pharmacol ; 406(3): 439-48, 2000 Oct 20.
Article in English | MEDLINE | ID: mdl-11040351

ABSTRACT

The renin angiotensin system is important in the regulation of fetal blood pressure. This study investigated the expression of angiotensin AT(1) and AT(2) receptors in the ovine fetal heart, aorta and umbilical artery, and how these receptors are affected by cortisol. Cortisol infusion into the fetus has previously been shown to cause an increase in fetal blood pressure. We hypothesised that this effect of cortisol is mediated by upregulation of the angiotensin AT(1) receptor. Binding studies performed on tissues with intact endothelium demonstrated both receptor subtypes in the fetal aorta and right ventricle, although the latter contained mainly angiotensin AT(2) receptors. In contrast, only angiotensin AT(1) receptors were found in the umbilical artery. Cortisol infusion into fetuses (3 mg/day for 3-5 days) caused a physiological increase in plasma cortisol levels to 29+/-4 nM. This was associated with an increase in systolic pressure (57.8+/-1.7 vs. 52.2+/-1.5 mm Hg, P<0.05), but cortisol had no effect on the density or affinity of angiotensin receptors, nor on the in vitro contractile responses of carotid and umbilical arterial rings to 5-microM angiotensin II. In conclusion, this study has demonstrated differential expression of angiotensin AT(1) and AT(2) receptors in the different regions of the ovine fetal cardiovascular system and that the angiotensin AT(1) receptor is functional. The lack of any effect of low doses of cortisol on these receptors and on the contractility of isolated fetal vessels to angiotensin II suggests cortisol acts by other mechanisms to raise fetal arterial pressure.


Subject(s)
Fetus/drug effects , Hydrocortisone/pharmacology , Receptors, Angiotensin/drug effects , Vasoconstriction/drug effects , 1-Sarcosine-8-Isoleucine Angiotensin II/metabolism , Animals , Binding, Competitive , Endothelium, Vascular/physiology , Female , In Vitro Techniques , Pregnancy , Receptor, Angiotensin, Type 1 , Receptor, Angiotensin, Type 2 , Receptors, Angiotensin/analysis , Receptors, Angiotensin/physiology , Sheep
11.
Clin Exp Pharmacol Physiol ; 27(1-2): 67-73, 2000.
Article in English | MEDLINE | ID: mdl-10696531

ABSTRACT

1. To measure the renal contribution to acid-base homeostasis during hypoxia (not associated with hypercapnia) and in response to the subsequent mild metabolic acidosis and to determine the effects of this hypoxia on the renal handling of sodium, studies were performed in six chronically catheterized foetal sheep (129-138 days gestation) before, during and for 1 h after a 2 h period of hypoxia. 2. Hypoxia was induced in the conscious ewe by infusing nitrogen into the trachea. Foetal arterial oxygen tension fell to 12.0 +/- 0.6 mmHg (P < 0.001). Carbon dioxide tension fell during hypoxia (P < 0.001) and was still somewhat reduced in the recovery period (P < 0.005). Arterial pH fell progressively to 7.19 +/- 0.08 in the recovery period (P < 0.05). Plasma bicarbonate concentrations fell (P < 0.001) and lactate rose (P < 0.001). 3. Urinary pH and the excretion rates of bicarbonate, titratable acid, ammonium and net acid did not change during hypoxia. Ammonium excretion and, hence, generation of new bicarbonate increased in the recovery period (P < 0.05). 4. Renal sodium excretion progressively increased and was greatest after normoxia was restored (P < 0.05). This natriuresis was due to a fall in the reabsorption of sodium by the proximal tubule (P < 0.05). Proximal reabsorption of sodium was directly related to foetal pH (P < 0.0001) and bicarbonate reabsorption (P < 0.001). 5. It was concluded that: (i) the foetal kidneys began to contribute to the maintenance of acid-base balance within the first hour of recovery from a 2 h episode of hypocapnic hypoxia, even though the acidosis was relatively mild; and (ii) a reduction in bicarbonate reabsorption was probably the most important factor that limited sodium reabsorption by the renal tubule during this experiment.


Subject(s)
Acid-Base Equilibrium/physiology , Acidosis/physiopathology , Fetus/physiology , Hypoxia/physiopathology , Kidney Tubules, Proximal/physiology , Acidosis/blood , Acidosis/urine , Animals , Bicarbonates/blood , Carbon Dioxide/blood , Chlorides/urine , Female , Hypoxia/blood , Hypoxia/urine , Kidney/physiology , Lactic Acid/blood , Oxygen/blood , Pregnancy , Sheep , Sodium/urine
12.
J Athl Train ; 35(3): 329-37, 2000 Jul.
Article in English | MEDLINE | ID: mdl-16558646

ABSTRACT

OBJECTIVE: To introduce an approach to shoulder rehabilitation that integrates the kinetic chain throughout the rehabilitation program while providing the theoretical rationale for this program. BACKGROUND: The focus of a typical rehabilitation program is to identify and treat the involved structures. However, in activities of sport and daily life, the body does not operate in isolated segments but rather works as a dynamic unit. Recently, rehabilitation programs have emphasized closed kinetic chain exercises, core-stabilization exercises, and functional programs. These components are implemented as distinct entities and are used toward the end of the rehabilitation program. DESCRIPTION: Kinetic chain shoulder rehabilitation incorporates the kinetic link biomechanical model and proximal-to-distal motor-activation patterns with proprioceptive neuromuscular facilitation and closed kinetic chain exercise techniques. This approach focuses on movement patterns rather than isolated muscle exercises. Patterns sequentially use the leg, trunk, and scapular musculature to activate weakened shoulder musculature, gain active range of motion, and increase strength. The paradigm of kinetic chain shoulder rehabilitation suggests that functional movement patterns and closed kinetic chain exercises should be incorporated throughout the rehabilitation process. CLINICAL ADVANTAGES: The exercises in this approach are consistent with biomechanical models, apply biomechanical and motor control theory, and work toward sport specificity. The exercises are designed to stimulate weakened tissue by motion and force production in the adjacent kinetic link segments.

13.
Eur J Pharmacol ; 378(2): 195-202, 1999 Aug 06.
Article in English | MEDLINE | ID: mdl-10478632

ABSTRACT

This study was performed to investigate the roles of angiotensin receptors (AT1 and AT2) in the contractility of uterine arteries during normal pregnancy and after angiotensin II levels have been elevated. Pregnant ewes were given intravenous infusions of saline for 24 h (control) or angiotensin II (30 ng kg(-1) min(-1)) for 2 or 24 h. The contractile responses of uterine arterial rings to angiotensin II (4 microM) and antagonists were then examined in vitro. Most uterine arteries were relatively insensitive to the vasoconstrictor effects of angiotensin II. In rings from control ewes an angiotensin AT2 antagonist enhanced (P < 0.05) the contractile responses to angiotensin II, suggesting that angiotensin AT2 receptors inhibited the angiotensin AT1 receptor mediated contractions. Uterine arterial rings from ewes given intravenous infusions of angiotensin II displayed greater (P < 0.05) contractile responses to angiotensin II in vitro compared to rings from control ewes. This was in part due to down regulation of angiotensin AT2 receptors. Surprisingly, while performing these experiments a small number of ewes had uterine arteries which were "hyperreactive" to angiotensin II (contractile responses 6-fold greater). These ewes also had abnormal renin angiotensin systems and had some features which are characteristic of those seen in preeclampsia. The "hyperreactivity" of these arteries could only in part be explained by down regulation of angiotensin AT2 receptors. It is concluded that in normal pregnancy angiotensin AT2 receptors play a role in maintaining an adequate uterine blood flow for the fetus. When angiotensin II levels are elevated for a prolonged period this protective effect is lost partly because angiotensin AT1 receptors are down regulated.


Subject(s)
Angiotensin II/physiology , Angiotensin I/physiology , Arteries/physiology , Muscle, Smooth, Vascular/physiology , Pregnancy, Animal , Receptors, Angiotensin/physiology , Uterus/blood supply , Animals , Anti-Arrhythmia Agents/pharmacology , Female , Hypersensitivity/genetics , In Vitro Techniques , Losartan/pharmacology , Muscle Contraction/physiology , Pregnancy , Receptors, Angiotensin/classification , Sheep
14.
J Gen Psychol ; 126(1): 97-110, 1999 Jan.
Article in English | MEDLINE | ID: mdl-10216972

ABSTRACT

Age differences in adults' memory for performed actions (e.g., wave hand) are sometimes smaller than age differences in memory for nonperformed phrases. In this study, we examined the conditions under which performance reduces age differences in recall. Younger and older adults performed or read verb-noun phrases that were either related (e.g., actions performed in a kitchen) or unrelated. Performance did not reduce age differences in recall of the exact verbs and nouns used to describe an action, but performance did reduce age differences in memory for the gist of related actions. Older adults especially had difficulty recalling the exact verb used to describe the action. These results suggest that older adults may have better memory for actions than is revealed by tests of verbatim recall. They may remember performing the action but not remember the exact words used to describe the action.


Subject(s)
Aging/physiology , Mental Recall/physiology , Psychomotor Performance/physiology , Vocabulary , Adolescent , Adult , Aged , Aged, 80 and over , Humans , Middle Aged
15.
Can J Nurs Leadersh ; 12(3): 18-23, 1999.
Article in English | MEDLINE | ID: mdl-11094935

ABSTRACT

The purpose of this study was to explore how nurses on geriatric assessment inpatient units perceived patient acuity. Three questions were developed and included: what variables do nurses use to define acuity; does variation exist between and among groups of nurses; and are there nursing activities taken for granted or overlooked that can contribute to the perception of acuity? The purposive sample included all the full time and part time nurses (11 RNs, 16 LPNs) working on the units. Focus groups were used to facilitate the data gathering for this qualitative study. Five themes were identified from the data and the program NUD*IST was used to visualize the relationships between the individual items and themes. Patient acuity was defined differently by the RNs and LPNs and is based on their reality and the realm of their mandated practice. A large category of indirect non patient related activities was found to contribute greatly to the nurses' perception of acuity. Two benefits of the study were: 1) provision of a breakdown of items nurses incorporate into their definition of acuity; 2) a list of categories to guide decision making when determining which category of staff is required to best meet the needs of the patients.


Subject(s)
Attitude of Health Personnel , Geriatric Assessment , Nursing Assessment/methods , Nursing Staff, Hospital/psychology , Nursing, Practical , Severity of Illness Index , Aged , Female , Focus Groups , Hospital Units , Humans , Job Description , Nursing Methodology Research , Nursing Staff, Hospital/education , Nursing Staff, Hospital/organization & administration , Nursing, Practical/education , Nursing, Practical/organization & administration
17.
Biol Neonate ; 73(4): 254-63, 1998.
Article in English | MEDLINE | ID: mdl-9551192

ABSTRACT

To determine the effects of circulating noradrenaline on fetal renal function noradrenaline was infused intravenously into 7 chronically catheterised fetal sheep (127-138 days) at a dose (1 microgram/kg/min) which resulted in plasma levels similar to those which occur during hypoxia. Fetal mean arterial pressure increased by approximately 14 mmHg (p < 0.001) and haematocrit rose (p < 0.005). Glomerular filtration rate rose from 3.85 +/- 0.47 (SEM) to 4.70 +/- 0.50 ml/min (p < 0.05) during the first hour and fractional reabsorption of sodium by the proximal tubule fell (p < 0.05) during the second hour. Urine flow rate increased from 0.61 +/- 0.13 to 1.18 +/- 0.24 ml/min (p < 0.001) and osmolar excretion increased from 78 +/- 15 to 153 +/- 36 mu osm/min (p < 0.005). By contrast lung liquid flow fell (p < 0.05), but the increase in urine flow was much greater than the decline in lung liquid. These findings suggest that during hypoxia, noradrenaline may play an important role in the maintenance of urine flow and consequently amniotic fluid volume and, as suggested by others, in the distribution of fluid between the vascular and interstitial compartments.


Subject(s)
Catheterization , Kidney/embryology , Norepinephrine/pharmacology , Absorption , Animals , Blood Pressure , Carbon Dioxide/blood , Female , Fetal Blood/metabolism , Fetus/physiology , Glomerular Filtration Rate , Heart Rate, Fetal , Infusions, Intravenous , Kidney/blood supply , Kidney/physiology , Kidney Tubules, Proximal/embryology , Kidney Tubules, Proximal/metabolism , Norepinephrine/administration & dosage , Oxygen/blood , Pregnancy , Sheep , Sodium/metabolism
18.
Pharm Res ; 15(2): 312-7, 1998 Feb.
Article in English | MEDLINE | ID: mdl-9523320

ABSTRACT

OBJECTIVE: The objective of this work was to determine plasma protein adsorption and macrophage phagocytosis of biodegradable polyanhydride, polylactic acid and polylactic-co-glycolic acid microspheres prepared by both spray-drying and solvent evaporation techniques. METHODS: Microspheres were characterized by scanning electron microscopy (SEM), confocal laser microscopy, particle size distribution and zeta (zeta) potential determination. Plasma protein adsorption onto the microspheres was determined using a fluoroaldehyde reagent. Phagocytosis was evaluated by incubating microspheres containing the angiotensin II antagonist, L-158,809, with the macrophages in the presence or absence of the phagocytosis inhibitor cythochalasin D. The extent of phagocytosis was established by fluorescence determination of L-158,809 and by optical microscopy. The effect of amphiphilic poly(ethylene glycol) (PEG) derivatives on phagocytosis was determined using PEG-distearate incorporated into the microspheres. RESULTS: The average diameter of the microspheres, which depended on the polymer and the initial formulation, ranged from 0.9 to 3.2 micrometers. Zeta potential studies showed strong negative values irrespective of the polymer used for the spray-dried formulations. The zeta potential was masked by the incorporation of PEG 400- or PEG 1,400-distearate in the formulation. Confocal laser microscopy showed a homogenous dispersion of PEG (measured as PEG-fluorescein) in the microspheres. Protein adsorption was not observed for any of the microsphere formulations following incubation with bovine serum. Incubation of microspheres with murine macrophages showed that PEG-distearate inhibited phagocytosis at appropriate levels (0.1% w/w). Higher levels > 1% w/w of PEG-distearate) resulted in enhanced association with macrophages, despite the presence of the phagocytosis inhibitor cytochalasin D, indicating fusion between the microspheres and the plasma membrane. CONCLUSIONS: These results demonstrate that spray-dried PEG-containing microspheres can be manufactured and that an appropriate concentration of this excipient in microspheres results in decreased phagocytosis.


Subject(s)
Blood Proteins/chemistry , Lactic Acid/chemistry , Microspheres , Phagocytosis , Polyglycolic Acid/chemistry , Polymers/chemistry , Adsorption , Animals , Cell Survival , Female , Macrophages/immunology , Mice , Microscopy, Electron, Scanning , Polyesters , Polylactic Acid-Polyglycolic Acid Copolymer , Surface Properties
19.
Pharm Res ; 14(7): 887-91, 1997 Jul.
Article in English | MEDLINE | ID: mdl-9244145

ABSTRACT

PURPOSE: To characterize and evaluate in vitro and in vivo the release mechanisms involved in spray-dried biodegradable microspheres having different Poly(D,L-lactide) blend formulations and containing an antihypertensive drug (L-158,809). METHODS: Microspheres and blended polymers were characterized by DSC, SEM, confocal laser microscopy and size analysis. In vitro release studies were evaluated by using microspheres made from various blends of high and low molecular weight polymer. In vivo studies were evaluated by L-158,809 antagonist AT1 function versus the shift of the normal dose-response curve of blood pressure induced by Angiotensine II. RESULTS: The average yield of L-158,809 microspheres (10% (w/w)) was 95% of the theoretical loading. The average diameter of the microspheres was from 1 to 3 micrometers. In all release experiments, a significant burst effect (< 15%) was observed followed by a near zero-order release kinetics. In vivo studies with two different formulations show a strong shift of angiotensin II dose-response curve. CONCLUSIONS: The release kinetics and photomicrographs suggest that the system is best described as a multi-parameter controlled released system in which the drug is molecularly dispersed. In vivo results demonstrating the controlled release of L-158,809.


Subject(s)
Angiotensin Receptor Antagonists , Antihypertensive Agents/pharmacology , Imidazoles/pharmacology , Tetrazoles/pharmacology , Angiotensin II/metabolism , Animals , Calorimetry, Differential Scanning , Dose-Response Relationship, Drug , Male , Microscopy, Confocal , Microscopy, Electron, Scanning , Microspheres , Polymers , Rats , Rats, Sprague-Dawley , Receptors, Angiotensin/metabolism
20.
J La State Med Soc ; 145(3): 101-5, 1993 Mar.
Article in English | MEDLINE | ID: mdl-8384648

ABSTRACT

Over the past two decades there has been an increasing trend toward ambulatory surgery. There has also been a corresponding emphasis in research in this area, with particular attention to perioperative management and preoperative selection of ambulatory patients. However, one area of limited information in the literature is postoperative management of the ambulatory surgery patient, in particular, discharge criteria from an ambulatory surgery unit. This paper will address the importance of this issue and provide an overview of the criteria considered in the current literature.


Subject(s)
Ambulatory Surgical Procedures , Patient Discharge , Aftercare , Humans , Patient Discharge/legislation & jurisprudence , Postoperative Care
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