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1.
Epidemiol Infect ; 142(9): 2000-12, 2014 Sep.
Article in English | MEDLINE | ID: mdl-24284038

ABSTRACT

Neisseria meningitidis is the main cause of bacterial meningitis and sepsis in the UK, and can potentially be lethal or cause long-term sequelae. Bexsero® (4CMenB) is a new multi-component vaccine approved by the European Commission for use in individuals aged ⩾2 months. A theoretical transmission model was constructed to assess the long-term effectiveness of Bexsero compared to standard care. The model was populated with UK-specific demographic data and calibrated to ensure that the transmission dynamics of meningococcal disease in the UK were adequately simulated. The model showed the best strategy to be a routine vaccination programme at ages 2, 3, 4, 12 months and 14 years combined with a 5-year catch-up programme in toddlers aged 12-24 months and adolescents aged 15-18 years. This would lead to a 94% reduction in meningococcal cases or 150 000 cases and 15 000 deaths over a 100-year time-frame.


Subject(s)
Meningococcal Infections/prevention & control , Meningococcal Vaccines/immunology , Adolescent , Adult , Aged , Child , Child, Preschool , Humans , Infant , Meningococcal Infections/epidemiology , Middle Aged , Models, Biological , Neisseria meningitidis/classification , Neisseria meningitidis/immunology , Uncertainty , United Kingdom/epidemiology , Young Adult
2.
Osteoarthritis Cartilage ; 17(6): 805-12, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19114312

ABSTRACT

OBJECTIVE: The infrapatellar fat pad (IPFP) has been identified as a source of anterior knee pain. Fibrosis and marked inflammatory infiltrate in the IPFP of patients with arthritis of the knee and reduction in pain post knee replacement in patients following resection of the IPFP have been observed. We have investigated changes in the IPFP of rats undergoing the monoiodoacetate (MIA) model of degenerative joint disease, a model that exhibits some histopathological similarities to osteoarthritis (OA). METHODS: Rats were injected intra-articularly with MIA and the development of weight bearing asymmetry was followed for 21 days as compared to vehicle-injected animals. In addition, IPFPs were removed from both ipsilateral and contralateral joints. Both inflammatory infiltrate and histopathological changes were analysed. RESULTS: MIA injection caused marked weight bearing asymmetry. Ipsilateral IPFP wet weights were significantly increased on days 1 and 3 in MIA-treated animals. MIA treatment also resulted in significant increases in IPFP total white blood cells and monocytes on days 1, 3, and 7 and neutrophils on days 1 and 3. This was supported by histopathological findings at early time points which progressed to adipocyte necrosis, IPFP fibrosis, patellar cartilage and subchondral bone necrosis with synovial hyperplasia at later timepoints. CONCLUSIONS: The current study clearly demonstrated that marked inflammatory changes in the IPFP occur during the early stage of the MIA model of OA which may contribute to the pain observed at this early stage. The role of the IPFP in later stages of the model needs to be further explored.


Subject(s)
Adipose Tissue/pathology , Arthritis, Experimental/pathology , Cartilage, Articular/pathology , Knee Joint/pathology , Osteoarthritis, Knee/pathology , Pain/pathology , Animals , Arthritis, Experimental/physiopathology , Male , Osteoarthritis, Knee/physiopathology , Pain Threshold , Rats , Rats, Wistar , Weight-Bearing/physiology
3.
Osteoarthritis Cartilage ; 17(1): 124-31, 2009 Jan.
Article in English | MEDLINE | ID: mdl-18562219

ABSTRACT

OBJECTIVE: To examine the role of mitogen-activated protein kinase-activated protein kinase 2 (MK2) in mediating the cellular response to pro-inflammatory cytokines in human primary osteoarthritis (OA) chondrocytes. METHODS: Delivery of a dominant negative MK2 was achieved in HeLa cells by adenoviral infection. Cellular heat shock protein (HSP27) activity was determined using a Bioplex assay. Primary OA chondrocytes were isolated by collagenase digestion of human articular cartilage. Phosphorylated MK2 was detected by immunoblotting and immunohistology. Transfection of primary chondrocytes with siRNA was achieved using cationic lipid and gene expression determined by real-time polymerase chain reaction. Production of prostaglandin E2 (PGE2) and matrixmetalloproteases (MMPs) was measured by enzyme-linked immunosorbent assay. RESULTS: Over-expression of a dominant negative MK2 inhibited HSP27 phosphorylation and significantly reduced both interleukin 1 (IL-1)beta and tumour necrosis factor (TNF)-alpha mediated release of PGE2 in HeLa cells over a 24h period. Phosphorylated MK2 was detected in OA articular cartilage and in isolated primary OA chondrocytes, where it was induced by IL-1beta. Transfection of OA chondrocytes with MK2 siRNA antisense significantly reduced both basal and IL-1beta induced PGE2 release. siRNA mediated MK2 knockdown also significantly reduced both basal and IL-1beta induced MMP13 expression and MMP13 and MMP3 protein release but had no effect on MMP1. CONCLUSIONS: Our data reveal that MK2 is active in OA human articular cartilage and in isolated primary human chondrocytes and that MK2 mediates the release of PGE2, MMP3 and MMP13. These findings suggest a role for MK2 in contributing to OA algesia and OA joint structural deterioration by mediating the downstream effects of p38 activation on PGE2 release and the expression and release of catabolic proteases.


Subject(s)
Cartilage, Articular/enzymology , Chondrocytes/enzymology , Intracellular Signaling Peptides and Proteins/physiology , Osteoarthritis, Knee/enzymology , Protein Serine-Threonine Kinases/physiology , Adenoviridae/genetics , Aged , Cartilage, Articular/metabolism , Cartilage, Articular/pathology , Cells, Cultured , Chondrocytes/metabolism , Chondrocytes/pathology , Dinoprostone/metabolism , Enzyme Activation/drug effects , Genetic Vectors , Humans , Interleukin-1beta/pharmacology , MAP Kinase Signaling System , Male , Middle Aged , Osteoarthritis, Knee/metabolism , Osteoarthritis, Knee/pathology , Peptide Hydrolases/biosynthesis , Phosphorylation , RNA, Small Interfering/genetics , Transfection
4.
Physiol Behav ; 94(3): 481-6, 2008 Jun 09.
Article in English | MEDLINE | ID: mdl-18452958

ABSTRACT

This study addresses the working memory capabilities of the male spontaneously hypertensive rat (SHR) strain as compared to the normotensive inbred strain, Wistar Kyoto (WKY), and the out bred Sprague Dawley (SD) rat as a normal control. The objective was to use two working memory tasks in the water maze with different strategic demands: forced alternation (FA) which allows the use of either an allocentric ("place") or egocentric ("response") localisation strategy and delayed matching-to-place (DMP) which requires an allocentric strategy. In the FA task, SHR reached criterion at the same rate as WKY and SD controls and were impaired to the same extent as WKY at the long (1 h) delay. Furthermore, both SHR and WKY were impaired relative to SD when the memory load was increased through the use of massed trials. In the DMP task, the performance of SHR did not differ from that of either of the control strains, either during training or in response to delay. These findings do not provide evidence of short-term memory impairments in the SHR, which is a commonly-used animal model of Attention Deficit Hyperactivity Disorder (ADHD) in humans.


Subject(s)
Memory, Short-Term/physiology , Rats, Inbred SHR/physiology , Analysis of Variance , Animals , Neuropsychological Tests , Rats , Rats, Inbred WKY , Rats, Sprague-Dawley
5.
Behav Brain Res ; 183(2): 169-77, 2007 Nov 02.
Article in English | MEDLINE | ID: mdl-17664015

ABSTRACT

This is the second in a series of studies that uses various configurations of the water radial arm to characterize the mnemonic systems in the spontaneously hypertensive rat (SHR) which is used frequently as a rodent model of attention deficit hyperactivity disorder. The first study indicated that SHR were impaired on a win-shift version of the task that required the use of spatial extra-maze cues to locate the hidden platform. The objective of the present study was to assess the performance of male SHR, Wistar-Kyoto (WKY) and Sprague-Dawley (SD) rats on (i) a win-stay version of the task that requires the use of proximal cue-based visual discrimination, and (ii) a conditioned cue preference task that is considered a measure of affective conditioning. In the win-stay task, SHR made fewer total errors than WKY and SD at the beginning of testing and after reversal of the value of the cues. In the conditioned cue preference task, SHR spent a similar amount of time in both arms; whereas, SD and WKY spent significantly more time in the arm with the cue that was associated with the platform. These findings indicate that SHR are not impaired on either the acquisition or reversal of a cued visual discrimination task in the radial water maze, but are impaired in terms of their performance on an affective learning task.


Subject(s)
Attention Deficit Disorder with Hyperactivity/physiopathology , Behavior, Animal/physiology , Conditioning, Operant/physiology , Cues , Maze Learning/physiology , Animals , Disease Models, Animal , Male , Rats , Rats, Inbred SHR , Rats, Inbred WKY , Rats, Sprague-Dawley , Space Perception/physiology , Species Specificity , Statistics, Nonparametric
6.
Am J Clin Nutr ; 66(4): 787-94, 1997 Oct.
Article in English | MEDLINE | ID: mdl-9322551

ABSTRACT

The Minimum Data Set (MDS), a Health Care Financing Administration (HCFA)-mandated resident assessment system used in community nursing homes, is potentially useful for assessing nutritional status. We compared anthropometric measures of nutritional status available in the MDS [weight and body mass index (BMI)] with other anthropometric and bioelectrical measures of nutritional status, not available on the MDS. We also studied associations of MDS-measured clinical characteristics of nursing home residents with anthropometric and bioelectrical measures of lower and higher nutritional status, defined as measures in the 25th percentile and below, and 75th percentile and above, respectively. Data were from a sample of residents of an academic long-term care facility (n = 186, 75% female, mean age 89.9 +/- 5.6 y). Results were as follows: 1) MDS measures of weight and BMI were significantly correlated with all the anthropometric and bioelectrical measures of nutritional status in women, and most measures in men; 2) some MDS variables, including poor oral intake and advanced cognitive decline, were significantly associated with two or more anthropometric and bioelectrical measures of low nutritional status; and 3) complaints of hunger were significantly associated with two or more anthropometric and bioelectrical measures of high nutritional status. Results suggest that 1) weight and BMI, available in the MDS, are correlated with other measures of nutritional status not available, and 2) MDS clinical variables are associated with measures of low and high nutritional status, and may be useful in identifying patients at nutritional risk.


Subject(s)
Homes for the Aged/statistics & numerical data , Inpatients/classification , Nursing Homes/statistics & numerical data , Nutrition Assessment , Aged , Aged, 80 and over , Anthropometry , Body Composition , Body Constitution , Boston , Cross-Sectional Studies , Electric Impedance , Female , Humans , Male , Nutritional Status , Odds Ratio , Sex Characteristics
7.
Sleep ; 20(2): 95-101, 1997 Feb.
Article in English | MEDLINE | ID: mdl-9143068

ABSTRACT

We tested the hypothesis that exercise would improve subjective sleep quality and activity in depressed elders. A 10-week randomized controlled trial was utilized. Participants consisted of a volunteer sample, aged > 60 with a diagnosis of major or minor depression or dysthymia. A total of 32 subjects aged 60-84 years with a mean age of 71.3 +/- 1.2 years was used. Intervention consisted of a supervised weight-training program three times a week or an attention-control group. Main outcome measures were Pittsburgh Subjective Sleep Quality Index (PSQI), Likert Scale of Subjective Sleep Quality and Quantity. Paffenbarger Activity Index. Geriatric Depression Scale (GDS). Beck Depression Inventory (BDI), Hamilton Rating Scale of Depression (HRSD), and the Medical Outcomes Survey Short Form 36 (SF-36). Results showed that exercise significantly improved all subjective sleep-quality and depression measures. Depression measures were reduced by approximately twice that of controls. Habitual activity was not significantly increased by exercise. Quality of life subscales significantly improved. In a forward stepwise multiple regression, percent improvement in GDS and percent increase in strength remained significant predictors of the improvement in total PSQI score (r = 0.71, p = 0.0002). In conclusion, weight lifting exercise was effective in improving subjective sleep quality, depression, strength, and quality of life without significantly changing habitual activity.


Subject(s)
Exercise , Sleep , Aged , Depressive Disorder/diagnosis , Female , Humans , Male , Quality of Life
8.
J Am Geriatr Soc ; 41(3): 333-7, 1993 Mar.
Article in English | MEDLINE | ID: mdl-8440860

ABSTRACT

Research indicates that lower extremity muscle weakness in the elderly is consistently related to impaired mobility and fall risk. Reversible components of the muscle weakness of aging include underuse syndromes and undernutrition, both of which are prevalent in nursing home populations. The Boston FICSIT study is a nursing home-based intervention to improve muscle strength through progressive resistance training of the lower extremities and/or multi-nutrient supplementation in chronically institutionalized subjects aged 70-100. Baseline measurements of falls, medical status, psychological variables, functional status, nutritional intake and status, body composition, muscle mass and morphology, muscle function, and gait and balance are taken. The nursing home residents are then randomly assigned to one of four treatment groups for 10 weeks: (1) high intensity progressive resistance training of the hip and knee extensors 3 days per week; (2) multi-nutrient supplementation with a 360-kcal high carbohydrate, low fat liquid supplement every day; (3) a combination of groups (1) and (2); and (4) a control group. Both non-supplemented groups receive a liquid placebo every day, and both non-exercising groups attend three sessions of "leisure activities" every week in order to control for the attentional aspects of the exercise and nutritional interventions. At the end of the 10-week period, all baseline measurements are re-assessed.


Subject(s)
Aged, 80 and over , Exercise , Food, Formulated , Frail Elderly , Aged , Boston , Geriatric Assessment , Health Promotion , Homes for the Aged , Humans
9.
J Gerontol A Biol Sci Med Sci ; 56(8): M497-504, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11487602

ABSTRACT

BACKGROUND: Pharmacological treatment of depression in geriatric patients is often difficult. Although unsupervised exercise has been shown to benefit younger depressed patients, there is no evidence that unsupervised exercise can be used as a maintenance treatment for depression in elderly patients. Our aim was to test the feasibility and efficacy of unsupervised exercise as a long-term treatment for clinical depression in elderly patients. METHODS: We studied 32 subjects (71.3 +/- 1.2 years of age, mean +/- SE) in a 20-week, randomized, controlled trial, with follow-up at 26 months. Subjects were community-dwelling patients with major or minor depression or dysthymia. Exercisers engaged in 10 weeks of supervised weight-lifting exercise followed by 10 weeks of unsupervised exercise. Controls attended lectures for 10 weeks. No contact was made with either group after 20 weeks until final follow-up. Blinded assessment was made with the Beck Depression Inventory (BDI), the Philadelphia Geriatric Morale Scale, and Ewart's Self Efficacy Scale at 20 weeks and with the BDI and physical activity questionnaire at 26 months. RESULTS: Patients randomized to the exercise condition completed 18 +/- 2 sessions of unsupervised exercise during Weeks 10 to 20. The BDI was significantly reduced at both 20 weeks and 26 months of follow-up in exercisers compared with controls (p <.05-.001). At the 26-month follow-up, 33% of the exercisers were still regularly weight lifting, versus 0% of controls (p <.05). CONCLUSIONS: Unsupervised weight-lifting exercise maintains its antidepressant effectiveness at 20 weeks in depressed elderly patients. Long-term changes in exercise behavior are possible in some patients even without supervision.


Subject(s)
Depressive Disorder/prevention & control , Depressive Disorder/rehabilitation , Exercise , Quality of Life , Aged , Aged, 80 and over , Female , Follow-Up Studies , Health Behavior , Humans , Male , Patient Satisfaction , Probability , Reference Values , Self Concept , Sensitivity and Specificity , Time Factors , Treatment Outcome
10.
J Gerontol A Biol Sci Med Sci ; 52(1): M27-35, 1997 Jan.
Article in English | MEDLINE | ID: mdl-9008666

ABSTRACT

BACKGROUND: Depression in elderly people may be contributed to by the multiple losses of aging. Exercise has the potential to positively impact many of these losses simultaneously. We tested the hypothesis that progressive resistance training (PRT) would reduce depression while improving physiologic capacity, quality of life, morale, function and self-efficacy without adverse events in an older, significantly depressed population. METHODS: We conducted a 10-week randomized controlled trial of volunteers aged 60 and above with major or minor depression or dysthymia. Subjects were randomized for 10 weeks to either a supervised PRT program three times a week or an attention-control group. RESULTS: A total of 32 subjects aged 60-84, mean age 71.3 +/- 1.2 yr, were randomized and completed the study. No significant adverse events occurred. Median compliance was 95%. PRT significantly reduced all depression measures (Beck Depression Inventory in exercisers 21.3 +/- 1.8 to 9.8 +/- 2.4 versus controls 18.4 +/- 1.7 to 13.8 +/- 2, p = .002; Hamilton Rating Scale of Depression in exercisers 12.3 +/- 0.9 to 5.3 +/- 1.3 versus controls 11.4 +/- 1.0 to 8.9 +/- 1.3, p = .008). Quality of life subscales of bodily pain (p = .001), vitality (p = .002), social functioning (p = .008), and role emotional (p = .02) were all significantly improved by exercise compared to controls. Strength increased a mean of 33% +/- 4% in exercisers and decreased 2% +/- 2% in controls (p < .0001). In a multiple stepwise regression model, intensity of training was a significant independent predictor of decrease in depression scores (r2 = .617, p = .0002). CONCLUSIONS: PRT is an effective antidepressant in depressed elders, while also improving strength, morale, and quality of life.


Subject(s)
Depression/therapy , Exercise Therapy , Aged , Depression/psychology , Exercise Therapy/adverse effects , Female , Humans , Male , Morale , Patient Compliance , Patient Selection , Psychiatric Status Rating Scales , Quality of Life , Treatment Outcome
11.
Physiol Behav ; 82(2-3): 477-87, 2004 Sep 15.
Article in English | MEDLINE | ID: mdl-15276813

ABSTRACT

The performance of male Long-Evans rats on the delayed match-to-place (DMP) version of the Morris water maze was assessed in two separate experiments; the first compared young (4 months) with middle-aged (16 months) rats, whereas the second compared middle-aged (14 months) with old (26 months) rats. Old rats continued to use a short-term memory strategy on the DMP task, but their performance on both search and recall trials was impaired relative to that of middle-aged animals. Rats of all ages habituated rapidly to visual distraction and the performance of old rats was not affected by exposure to a mild predator stress in the form of cat urine. The performance of the middle-aged rats did not differ significantly from that of young rats, even when they were challenged on recall trials by visual distraction or by exposure to predator odour. These results do not provide strong support for the prediction that visual distraction and psychological stress would interact with age in affecting spatial short-term memory in Long-Evans rats.


Subject(s)
Aging/psychology , Field Dependence-Independence , Problem Solving , Psychomotor Performance , Stress, Psychological/psychology , Animals , Discrimination Learning , Male , Mental Recall , Rats , Rats, Long-Evans , Time Factors
12.
J Nutr Health Aging ; 4(1): 5-12, 2000.
Article in English | MEDLINE | ID: mdl-10828934

ABSTRACT

BACKGROUND: Frail institutionalized elders have a high prevalence of nutritional risk factors, undernutrition, weight loss, and nutrition-related morbidity and excess mortality. Little information is available on effective means to intervene in this setting. HYPOTHESES: We tested the hypothesis that addition of multinutrient oral supplements to the diet of frail elders would improve their overall nutritional status and functional level. METHODS: Fifty nursing home residents aged 88+/-1 yr. were followed for 10 weeks in the course of a randomized controlled trial of supplementation with a multinutrient liquid supplement vs. a non-nutritive placebo drink. Three-day food weighing was used to analyze their habitual dietary intake before and during the final week of the intervention. Nutritional status was further assessed with nutritional biochemistries, anthropometric measurements, and body composition analysis as well as physical and functional performance tests. RESULTS: The nutritional supplement was consumed with high compliance, but did not significantly augment total caloric intake. Supplementation was associated with significant reductions in total energy, protein, fat, water, fiber, and many vitamins and minerals in the habitual diet of these nursing home residents. Nutritional status improved in terms of folate levels in serum, but no other measured vitamin or mineral indices. Body composition analysis revealed a small gain in weight, increases in fat stores, but no improvement in lean tissue mass associated with supplemention. No physical performance or functional gains were associated with supplementation. CONCLUSION: Short-term nutritional supplementation in elders at nutritional risk is offset by simultaneous reduction in voluntary food intake. It seems likely that changing other components of energy expenditure such as physical activity levels or basal metabolism may be required to produce overall improvements in nutritional intake in this setting.


Subject(s)
Aging , Dietary Supplements , Frail Elderly , Nutritional Status , Aged , Aged, 80 and over , Body Composition , Energy Intake , Female , Folic Acid/blood , Humans , Male , Nursing Homes , Patient Compliance , Placebos
13.
Neuroscience ; 274: 289-98, 2014 Aug 22.
Article in English | MEDLINE | ID: mdl-24905438

ABSTRACT

Attention-deficit hyperactivity disorder (ADHD) is a prevalent neurodevelopmental disorder characterized by overactivity, impulsiveness and attentional problems, including an increase in distractibility. A structure that is intimately linked with distractibility is the superior colliculus (SC), a midbrain sensory structure which plays a particular role in the production of eye and head movements. Although others have proposed the involvement of such diverse elements as the frontal cortex and forebrain noradrenaline in ADHD, given the role of the colliculus in distractibility and the increased distractibility in ADHD, we have proposed that distractibility in ADHD arises due to collicular sensory hyper-responsiveness. To further investigate this possibility, we recorded the extracellular activity (multi-unit (MUA) and local field potential (LFP)) in the superficial visual layers of the SC in an animal model of ADHD, the New Zealand genetically hypertensive (GH) rat, in response to wholefield light flashes. The MUA and LFP peak amplitude and summed activity within a one-second time window post-stimulus were both significantly greater in GH rats than in Wistar controls, across the full range of stimulus intensities. Given that baseline firing rate did not differ between the strains, this suggests that the signal-to-noise ratio is elevated in GH animals. D-Amphetamine reduced the peak amplitude and summed activity of the multi-unit response in Wistar animals. It also reduced the peak amplitude and summed activity of the multi-unit response in GH animals, at higher doses bringing it down to levels that were equivalent to those of Wistar animals at baseline. The present results provide convergent evidence that a collicular dysfunction (sensory hyper-responsiveness) is present in ADHD, and that it may underlie the enhanced distractibility. In addition, D-amphetamine - a widely used treatment in ADHD - may have one of its loci of therapeutic action at the level of the colliculus.


Subject(s)
Attention Deficit Disorder with Hyperactivity/physiopathology , Central Nervous System Agents/pharmacology , Dextroamphetamine/pharmacology , Superior Colliculi/physiopathology , Visual Perception/physiology , Action Potentials/drug effects , Animals , Attention Deficit Disorder with Hyperactivity/drug therapy , Disease Models, Animal , Female , Male , Microelectrodes , Photic Stimulation , Rats , Rats, Wistar , Superior Colliculi/drug effects , Visual Perception/drug effects
14.
Brain Res Bull ; 82(5-6): 259-63, 2010 Jul 30.
Article in English | MEDLINE | ID: mdl-20457228

ABSTRACT

The spontaneously hypertensive rat (SHR), which is used as an animal model of ADHD, displays numerous behavioural differences on learning and memory tasks. This study characterises differences in neural Zif268 expression in male SHR, Wistar Kyoto (WKY) and Sprague-Dawley (SD) rats after a 10-min forced swim. Swim stress increased Zif268 expression in the hippocampus of SHR only. In addition, SHR had increased expression in the prefrontal cortex, dorsal striatum and decreased expression in the nucleus accumbens shell in comparison to WKY and SD; and increased expression in the amygdala compared to SD. These findings: (i) support previous research indicating that SHR have altered neurobiological response to stressors, (ii) extends the characterisation of multiple memory systems in SHR to include differences in Zif268 expression in brain regions underlying their altered behaviour and (iii) supports previous findings that SHR may have a specific deficit within the shell of the nucleus accumbens.


Subject(s)
Early Growth Response Protein 1/metabolism , Gene Expression Regulation/physiology , Hippocampus/metabolism , Rats, Inbred SHR/physiology , Stress, Psychological/pathology , Swimming/psychology , Analysis of Variance , Animals , Disease Models, Animal , Early Growth Response Protein 1/genetics , Gene Expression Regulation/genetics , Male , Rats , Rats, Inbred WKY , Rats, Sprague-Dawley , Species Specificity
15.
Neurobiol Learn Mem ; 87(2): 285-94, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17056285

ABSTRACT

This study further characterises the use of mnemonic systems in the spontaneously hypertensive rat (SHR), which is frequently used as a rodent model of attention deficit hyperactivity disorder. The objective of this study was to assess the preference of male SHR, Wistar-Kyoto (WKY) and Sprague-Dawley (SD) rats for a place or response strategy when trained on an ambiguous T-maze task, and also to examine whether all strains acquired information about both strategies during ambiguous training, regardless of their preferred strategy. In the first experiment, SHR and WKY showed a preference for a response strategy on the ambiguous T-maze task; in contrast, SD displayed a preference for a place strategy. In the second experiment, all strains demonstrated that they learned information about both the response and place strategies during ambiguous training. However, on a conditioned place preference test SHR did not display as strong a preference for the place arm as WKY and SD. This finding supports previous research in a conditioned cue preference test, in which SHR did not display a preference for the cue associated with the platform. These observations that the strains differ with respect to behavioural strategy in a learning task suggest that they differ in the underlying neural circuitry that serves goal-directed behaviour, and are consistent with SHR having deficits associated with the nucleus accumbens.


Subject(s)
Hypertension/physiopathology , Maze Learning/physiology , Space Perception/physiology , Analysis of Variance , Animals , Behavior, Animal , Choice Behavior/physiology , Hypertension/genetics , Male , Rats , Rats, Inbred SHR , Rats, Inbred WKY , Rats, Sprague-Dawley , Species Specificity
16.
J Hered ; 96(7): 821-8, 2005.
Article in English | MEDLINE | ID: mdl-16150951

ABSTRACT

The Affymetrix canine GeneChip with 23,836 probe sets was used to look for cartilage genes that are significantly altered in response to mechanical impact. The model using canine articular cartilage explants loaded in vitro has been described previously (Chen et al., J Orthop Res 19:703-711, 2001). It is our hypothesis that genes that are activated or repressed in articular cartilage after impact injury initiate cartilage degeneration, leading to osteoarthritis in dogs. Gene expression of known cartilage genes was generally consistent with cartilage biology. A total of 528 genes were significantly (P < .01) up- or down- regulated in response to mechanical damage. After applying the strict Bonferroni correction, 172 remained significantly affected. One of these genes, MIG-6/gene 33, was chosen for verification by real- time quantitative reverse transcriptase polymerase chain reaction (RT-PCR). A 3.8- fold increase in expression was confirmed, consistent with the microarray chip data. Deficiencies in the current annotation of the canine chip are discussed. Gene expression studies with the Affymetrix canine GeneChip are potentially valuable, but await more complete annotation.


Subject(s)
Cartilage, Articular/chemistry , Cartilage, Articular/injuries , Dogs/genetics , Gene Expression Regulation/genetics , Animals , Cluster Analysis , Dogs/injuries , Down-Regulation/genetics , Female , Male , Oligonucleotide Array Sequence Analysis/methods , Oligonucleotide Array Sequence Analysis/veterinary , Reverse Transcriptase Polymerase Chain Reaction/methods , Up-Regulation/genetics
17.
Osteoarthritis Cartilage ; 9(5): 499-507, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11467899

ABSTRACT

OBJECTIVE: Little is known about the effects of severe repetitive loading on articular cartilage chondrocytes, even though epidemiological studies associate this type of loading with osteoarthritis. We hypothesize that repetitive loading can kill cartilage chondrocytes in a dose-related manner. DESIGN: Large cartilage-on-bone specimens were cut from the patella groove of bovine knees obtained directly from a slaughterhouse. Cartilage was loaded using a flat impermeable indenter in such a manner that the loaded region was supported naturally by surrounding cartilage and subchondral bone. Specimens received 3600 cycles of compressive loading at 1 Hz, with the peak load lying in the range 1-70% of the force required to damage cartilage in a single loading cycle (35 MPa). Cell viability was assessed in thick sections of loaded and control cartilage using a paravital staining method: fluorescein diacetate stained live cells green, and propidium iodide stained dead cells red. The assay was validated on cartilage which had been subjected to repeated freeze-thaw cycles to kill the chondrocytes. RESULTS: Paravital staining revealed 100% cell death after one freeze-thaw cycle at -196 degrees C and three cycles at -20 degrees C. Baseline chondrocyte viability was 80% in unloaded cartilage, and viability decreased when applied compressive loading exceeded 6 MPa. Above this threshold, cell viability was inversely proportional to applied stress. When gross damage to the cartilage surface first became evident, above 14 MPa, 40% of cells remained viable. Load-induced chondrocyte death was greatest in the surface zone, and extended beyond the loaded area. Electron micrographs indicated that some cells were dying by apoptosis. CONCLUSIONS: Some chondrocytes are much more vulnerable to repetitive mechanical loading than others, suggesting that vigorous activity may lead to cell death in articular cartilage.


Subject(s)
Cartilage, Articular/physiology , Chondrocytes/metabolism , Animals , Apoptosis , Cattle , Hindlimb/physiology , Joints/physiology , Osteoarthritis, Knee/etiology
18.
J Biochem Mol Toxicol ; 12(4): 205-12, 1998.
Article in English | MEDLINE | ID: mdl-9580872

ABSTRACT

Full-length cDNA clones encoding FMO1 and FMO5 have been isolated from a library constructed with mRNA from the liver of a female CD-1 mouse. The derived sequence of FMO1 contains 2310 bases: 1596 in the coding region, 301 in the 5'-flanking region, and 413 in the 3'-flanking region. The sequence for FMO5 consists of 3168 bases; 1599 in the coding region, 812 in the 5'-flanking region, and 757 in the 3'-flanking region. The sequence of FMO1 encodes a protein of 532 amino acids with a predicted molecular weight of 59.9 kDa and shows 83.3% identity to human FMO1 and 83-94% identity to other FMO1 homologs. FMO5 encodes a protein of 533 amino acids with a predicted molecular weight of 60.0 kDa and 84.1% identity to human FMO5 and 83-84% identity to other FMO5 orthologs. Two GxGxxG putative pyrophosphate binding domains exist beginning at positions 9 and 191 for FMO1, and 10 and 192 for FMO5. Mouse FMO1 and FMO5 were expressed in E. coli and show similar mobility to the native proteins as determined by SDS-PAGE. The expressed FMO1 protein showed activity toward methimazole, and FMO5 was active toward noctylamine. In addition, FMO1 was shown to metabolize radiolabeled phorate, whereas FMO5 showed no activity toward phorate.


Subject(s)
DNA, Complementary/genetics , DNA, Recombinant/genetics , Gene Expression Regulation, Enzymologic/physiology , Isoenzymes/genetics , Oxygenases/genetics , Animals , Base Sequence , Cloning, Molecular , Female , Humans , Mice , Mice, Inbred Strains , Molecular Sequence Data , Rabbits , Sequence Homology, Amino Acid , Species Specificity , Structure-Activity Relationship
19.
Arch Biochem Biophys ; 347(1): 9-18, 1997 Nov 01.
Article in English | MEDLINE | ID: mdl-9344459

ABSTRACT

The sequence of mouse flavin-containing monooxygenase 3 (FMO3) was obtained from several clones isolated from a mouse liver cDNA library. The nucleotide sequence of mouse FMO3 was 2020 bases in length containing 37 bases in the 5' flanking region, 1602 in the coding region, and 381 in the 3' flanking region. The derived protein sequence consisted of 534 amino acids including the putative flavin adenine dinucleotide and NADP+ pyrophosphate binding sites (characteristic of mammalian FMOs) starting at positions 9 and 191, respectively. The mouse FMO3 protein sequence was 79 and 82% identical to the human and rabbit FMO3 sequences, respectively. Mouse FMO3 was expressed in Escherichia coli and compared to E. coli expressed human FMO3. The FMO3 proteins migrated with the same mobility ( approximately 58 kDa) as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting. The expressed FMO3 enzymes (mouse and human forms) were sensitive to heat and reacted in a similar manner toward metal ions and detergent. Catalytic activities of mouse and human FMO3 were high toward the substrate methimazole; however, in the presence of trimethylamine and thioacetamide, FMO-dependent methimazole oxidation by both enzymes was reduced by greater than 85%. Other substrates which inhibited methimazole oxidation were thiourea and thiobenzamide and to a lesser degree N,N-dimethylaniline. When probed with mouse FMO3 cDNA, FMO3 transcripts were detected in hepatic mRNA samples from female mice, but not in samples from males. FMO3 was detected in mRNA samples from male and female mouse lung, but FMO3 message was not detected in mouse kidney sample from either gender. Results of immunoblotting confirmed the tissue- and gender-dependent expression of mouse FMO3.


Subject(s)
Oxygenases/chemistry , Oxygenases/genetics , Amino Acid Sequence , Animals , Base Sequence , Catalysis , Cloning, Molecular , Electrophoresis, Polyacrylamide Gel , Enzyme Inhibitors/pharmacology , Enzyme Stability , Escherichia coli/genetics , Female , Gene Expression , Humans , Hydrogen-Ion Concentration , Liver/enzymology , Male , Methimazole/metabolism , Mice , Molecular Sequence Data , Oxygenases/metabolism , RNA, Messenger/analysis , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism , Sequence Analysis, DNA , Sequence Homology, Amino Acid
20.
N Engl J Med ; 330(25): 1769-75, 1994 Jun 23.
Article in English | MEDLINE | ID: mdl-8190152

ABSTRACT

BACKGROUND: Although disuse of skeletal muscle and undernutrition are often cited as potentially reversible causes of frailty in elderly people, the efficacy of interventions targeted specifically at these deficits has not been carefully studied. METHODS: We conducted a randomized, placebo-controlled trial comparing progressive resistance exercise training, multinutrient supplementation, both interventions, and neither in 100 frail nursing home residents over a 10-week period. RESULTS: The mean (+/- SE) age of the 63 women and 37 men enrolled in the study was 87.1 +/- 0.6 years (range, 72 to 98); 94 percent of the subjects completed the study. Muscle strength increased by 113 +/- 8 percent in the subjects who underwent exercise training, as compared with 3 +/- 9 percent in the nonexercising subjects (P < 0.001). Gait velocity increased by 11.8 +/- 3.8 percent in the exercisers but declined by 1.0 +/- 3.8 percent in the nonexercisers (P = 0.02). Stair-climbing power also improved in the exercisers as compared with the nonexercisers (by 28.4 +/- 6.6 percent vs. 3.6 +/- 6.7 percent, P = 0.01), as did the level of spontaneous physical activity. Cross-sectional thigh-muscle area increased by 2.7 +/- 1.8 percent in the exercisers but declined by 1.8 +/- 2.0 percent in the nonexercisers (P = 0.11). The nutritional supplement had no effect on any primary outcome measure. Total energy intake was significantly increased only in the exercising subjects who also received nutritional supplementation. CONCLUSIONS: High-intensity resistance exercise training is a feasible and effective means of counteracting muscle weakness and physical frailty in very elderly people. In contrast, multi-nutrient supplementation without concomitant exercise does not reduce muscle weakness or physical frailty.


Subject(s)
Energy Intake , Exercise Therapy , Food, Fortified , Frail Elderly , Aged , Aged, 80 and over , Body Composition , Female , Gait , Humans , Male , Muscles/physiology , Nutritional Status , Physical Endurance
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