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R Jackson

Publications and source records attributed to R Jackson.

At least 181 records · Page 10Linked to original sources
PubMed1996

Ethnic differences in blood pressure: findings from the Fletcher Challenge-Auckland University Heart and Health Study.

AIMS: To investigate the determinants of ethnic differences in blood pressure, hypertension and the prevalence of additional risk factors for cardiovascular disease among a New Zealand population. METHODS: Baseline data from the Fletcher Challenge-University of Auckland Heart and Health Study were analysed for ethnic differences in blood pressure, and the likelihood of those with hypertension having other major cardiovascular disease risk factors was estimated. RESULTS: Maori and Pacific Islands participants had mean diastolic blood pressure up to 3 mmHg higher than Europeans, but Pacific Islands people had mean systolic blood pressure 3-4 mmHg lower than Europeans and Maori respectively. After adjustment for age and gender almost 20% of Maori, 16% of Pacific Islands and 11% of European people were classified as hypertensive. Adjustment for body mass index and alcohol consumption almost eliminated ethnic differences in blood pressure, and body mass index was found to be the single most important modifiable determinant of raised blood pressure. Greater proportions of Maori (15%) and Pacific Islands people (14%) with hypertension had multiple additional cardiovascular risk factors compared with Europeans (8%), but similar proportions were on antihypertensive drug treatment. CONCLUSIONS: Efforts to reduce obesity have the potential to significantly reduce raised blood pressure among Maori and Pacific Islands people. Overall cardiovascular risk is more likely to be higher in Maori and Pacific Islands people than in Europeans with hypertension, indicating that greater proportions of Maori and Pacific Islands people with high blood pressure should be receiving treatment.

Adult↗
PubMed1996

Sex differences in case fatality before and after admission to hospital after acute cardiac events: analysis of community based coronary heart disease register.

OBJECTIVE: To determine whether the reported higher case fatality in hospital after an acute cardiac event in women can be explained by sex differences in mortality before admission and in baseline risk factors. DESIGN: Analyses of data from a community based coronary heart disease register. SETTING: Auckland region, New Zealand. SUBJECTS: 5106 patients aged 25-64 years with an acute cardiac event leading to coronary death or definite myocardial infarction within 28 days of onset, occurring between 1986 and 1992. MAIN OUTCOME MEASURES: Case fatality before admission, 28 day case fatality for patients in hospital, and total case fatality after an acute cardiac event. RESULTS: Despite a more unfavourable risk profile women tended to have lower case fatality before admission than men (crude odds ratio 0.88; 95% confidence interval 0.77 to 1.02). Adjustment for age, living arrangements, smoking, medical history, and treatment increased the effect of sex (0.72; 0.60 to 0.86). After admission to hospital, women had a higher case fatality than men (1.76; 1.43 to 2.17), but after adjustment for confounders this was reduced to 1.18 (0.89 to 1.58). Total case fatality 28 days after an acute cardiac event showed no significant difference between men and women (0.85; 0.70 to 1.02) CONCLUSIONS: The higher case fatality after an acute cardiac event in women admitted to hospital is largely explained by differences in living status, history, and medical treatment and is balanced by a lower case fatality before admission.

Adult↗
PubMed1996

Trends in the use of blood pressure lowering medications in Auckland, and associated costs, 1982-94.

AIM: To describe the trends to the use of blood pressure lowering medication and associated costs in Auckland, New Zealand between 1982 and 1994. METHODS: Three cross sectional surveys of cardiovascular risk factors in people aged 35-64 years have been conducted in the Auckland region in 1982, 1986-8 and 1993-4, with random selection of 3804 European men and women from Auckland electoral rolls. RESULTS: Mean systolic and diastolic blood pressure fell significantly in both sexes between 1982 and 1993-4. There was a possible trend towards a decrease in the proportion of the survey population taking blood pressure lowering drugs with 9.3% on medication in 1982 and 8.0% in 1993-4, while the number of drugs prescribed per person for blood pressure control declined from 1.41 to 1.15. As a percentage of the total antihypertensive drug use in the population, diuretic use dropped from 40.3% to 11.7%, and beta blockers decreased from 36% to 27%. Angiotensin converting enzyme (ACE) inhibitors that were unavailable in 1982, were the most commonly prescribed antihypertensive at 35.8% in 1993-4 and calcium antagonists increased from 2% in 1982 to 22.1% in 1993-4. In 1995 dollars the average daily cost of blood pressure lowering medication per person has increased from 35 cents in 1982 to 76 cents in 1994. CONCLUSION: Over the 12 year survey period ACE inhibitors, beta blockers and calcium antagonists have replaced diuretics as the major antihypertensive drugs used in the Auckland population. This has resulted in an increase in the average daily cost of antihypertensive drug therapy per person of approximately 100% in the period 1982-94.

Adult↗
PubMed1996

Trends and determinants of blood pressure in Auckland, New Zealand 1982-94.

AIM: To describe blood pressure trends in Auckland, New Zealand from 1982 to 1994 and assess possible explanations for the trends. METHODS: Three cross sectional surveys of cardiovascular risk factors were undertaken in 1982, 1986-8 and 1993-4, with a total of 3806 European men and women aged 35-64 years randomly selected from Auckland electoral rolls. RESULTS: Mean systolic blood pressure fell in males from 132.2 mmHg in 1982 to 126.3 mmHg in 1993-4, and in females from 125.9 mmHg in 1982 to 121.7 mmHg in 1993-4. Both male and female diastolic mean blood pressure decreased more than 6 mmHg over the 12 years. The prevalence of antihypertensive drug use fell over the 12 year period. Regression analysis revealed a positive association between blood pressure and blood lipids. Body mass index (BMI) was also positively related to blood pressure while cigarette smoking was inversely related. However, concurrent trends in blood lipids, BMI and cigarette smoking could account for less than 6% of the average decline in systolic blood pressure over the 12 year period. CONCLUSION: There has been a substantial fall in mean blood pressure levels in Auckland adults aged 35-64 years which appears to be due to a shift in the general population blood pressure. The reduction in blood pressure is not explained by changes in pharmaceutical interventions and only a small part of the decline can be explained by concurrent trends in cardiovascular risk factors.

Adult↗
PubMed1996

New Zealand guidelines for the management of dyslipidaemia: implications for treatment in an urban New Zealand population.

AIMS: The paper uses coronary heart disease risk factor prevalence data from a defined urban population to assess the potential impact of implementing the New Zealand National Heart Foundation "Guidelines for detection and management of dyslipidaemia" on the treatment of dyslipidaemia in New Zealand. METHODS: Coronary heart disease risk factor data was collected on an age stratified random sample of Auckland residents aged 35-74 years. The 10 year absolute risk of coronary heart disease was calculated for each participant aged between 35-64 years and management options determined from the National Heart Foundation guidelines. The Framingham equation used in these guidelines was used to extrapolate the 10 year risk of a coronary event in the 65-74 year age group. The proportions of participants potentially requiring treatment with lipid modifying medication were identified and extrapolated to the New Zealand European population. A sensitivity analysis was undertaken to assess the impact of 5% and 10% reductions in total cholesterol following dietary intervention on numbers meeting the drug treatment criteria. RESULTS: The proportion of participants potentially requiring lipid modifying treatment based on the guidelines was considerably higher than estimates of current treatment rates in each age group. The number meeting the treatment criteria increased dramatically with age. By the age of 65-74 years one in five participants met the drug treatment criteria. A 5% and 10% reduction in total cholesterol following dietary intervention reduced the proportion of participants potentially requiring drugs by almost one quarter and one half respectively. CONCLUSION: The approach taken by the New Zealand National Heart Foundation guidelines appropriately gives highest priority to patients at highest risk of a coronary event. If this high risk approach is extrapolated to older age groups, it will lead to more drug treatment among the elderly. Further evidence from randomised controlled trials on benefits of using cholesterol modifying medication in older age groups is required. Future guidelines need to address specifically criteria for use of lipid modifying medications in older age groups. Reductions in the numbers meeting drug treatment criteria following 5% and 10% reductions in total cholesterol reinforces the importance of dietary management.

Adult↗
PubMed1996

The increasing prevalence of obesity in New Zealand: is it related to recent trends in smoking and physical activity?

AIMS: To describe recent trends in body mass in Auckland, and to determine whether associated changes in cigarette smoking and physical activity could explain these trends. METHODS: Risk factors for coronary heart disease were measured in three age-stratified random samples of Europeans aged 35-64 years using a standard protocol in 1982, 1986-8 and 1993-4. Body mass index (BMI) was calculated as weight in kg/(height in m2), with overweight or obese being defined as BMI>25. Results. The age-standardised mean BMI increased from 26.6 (25.4-25.8) to 26.4 (26.2-26.7) in men and from 24.6 (24.2-24.9) to 25.1 (24.8-25.5) in women between 1982 and 1993-4. The prevalence of overweight and obese people increased from 52.8% (48.1-57.7) to 64.2% (58.1-70.3) in men and from 36.5% (31.5-41.5) to 44.9% (39.7-50.1) in women. Self reported cigarette smoking declined between 1982 and 1993-94 with an associated increase in the prevalence of ex-smokers. The change in smoking status accounted for only 7% and 10% of the observed increase in BMI in men and women respectively. Most of the observed change in BMI was due to a general increase in BMI in all smoking categories in both sexes. The prevalence o leisure time physical activity increased in both sexes between 1986-88 and 1993-94 while work physical activity decreased. The change in physical activity should have decreased mean BMI by approximately 4% in men and 14% in women. As with smoking there was a trend towards increasing mean BMI irrespective of the activity undertaken. CONCLUSION: Recent trends in smoking cessation explain only a small percentage of the increase in body mass while the trends in physical activity would have predicted a small decrease in the prevalence of obesity, contrary to the observed trends. By exclusion, an increase in total energy intake, is the most likely explanation for the observed trends.

Adult↗
PubMed1996

Ethnic differences and recent trends in coronary heart disease incidence in New Zealand.

AIMS: This study compares recent coronary heart disease morbidity and mortality rates and ten year trends for Maori, Pacific Islands people and Europeans living in New Zealand. METHODS: Fatal coronary heart disease rates (mortality) and nonfatal hospitalisation rates for myocardial infarctions (morbidity) from 1983-92 were assessed and compared for males and females in each ethnic group, aged 35 to 64 years, using data from the Auckland Region Coronary or Stroke Study (ARCOS), a community-based coronary heart disease surveillance programme. RESULTS: The recent 1990-2 mean coronary heart disease mortality rate for Maori men (232/100 000) was almost double the rate for Pacific Islands men (135/100 000 p=0.008) and more than double the rate for European men (103/100 000 p=0.001). Maori women had a three-fold higher mean mortality rate (85/100 000) than European women (25/100 000 p=0.02). The morality rate for Pacific Islands women (42/100 000) was midway between the other ethnic groups. Over the decade 1983-92 coronary heart disease mortality rates have decreased significantly by approximately 5% per year for European men and women. Rates for Maori and Pacific Islands people also appear to have fallen although the precision of these estimates are low. Morbidity rates in 1990-2 were similar among men in all three ethnic groups. Among women, morbidity was approximately half the male rates and there were no clear differences between the ethnic groups. Between 1983 and 1992 morbidity rates declined significantly for European men (p=0.008) and women (p=0.02) by approximately 5% per year. Among Maori and Pacific Islands people the trends were variable. CONCLUSION: Maori men and women continue to experience more than double the coronary heart disease mortality rates than Europeans. Mortality rates for Pacific Islands people are intermediate between Maori and European. Both coronary heart disease mortality and morbidity rates are declining in Europeans; there appears to have been a decline in coronary heart disease mortality for Maori and Pacific Islands groups but not in morbidity rates which may have increased. Given the trend towards a decline in coronary heart disease mortality for Maori and Pacific Islands people, the most likely explanation for the apparent increase in morbidity is improved access to secondary health care services and greater awareness of coronary health disease symptoms.

Adult↗
PubMed1996

Multiplex polymerase chain reaction for adenovirus and herpes simplex virus in eye swabs.

Adenoviruses and herpes simplex virus (HSV) can cause clinically indistinguishable episodes of acute eye disease. Adenovirus infection is associated with nosocomial outbreaks and HSV may result in episodes of recurrent ocular inflammation. In a comparison of multiplex PCR for the two viral DNAs and virus isolation in cell culture, identical results were obtained for 18 of 20 specimens (positive for adenovirus in 5, HSV in 5, and negative in 8). One specimen was falsely negative for each viral DNA. Inclusion of human beta-globin primers in the adenovirus-HSV reaction was precluded by a consequential 10--100-fold reduction in sensitivity for the two viral targets and by the failure of beta-globin DNA amplification at the annealing temperature (45 degrees C) required to ensure detection of adenoviruses of serotypes 7 and 11 with the selected adenovirus primers. A single-target beta-globin PCR gave positive results with 19 of the 20 specimens prepared by treatment with proteinase K lysis buffer, indicating the effectiveness of this simple DNA extraction procedure. Nonetheless, the availability of effective antiviral therapy for HSV made monitoring for extraction failure using human primers crucial to avoid false-negative results for HSV DNA. Adenovirus-HSV PCR has considerable potential for the rapid diagnosis of viral eye disease particularly if beta-globin primers can be included in the reaction.

Adenovirus Infections, Human↗
PubMed1996

Differences between respondents and nonrespondents in a multicenter community-based study vary by gender ethnicity. The Atherosclerosis Risk in Communities (ARIC) Study Investigators.

This study provides data on differences between respondents and nonrespondents by gender and ethnicity in a multicenter community-based study that is rarely collected and that may be useful for estimating bias in prevalence estimates in other studies. Demographic, general health, and cardiovascular risk factors were examined in black and white respondents and nonrespondents to the Atherosclerosis Risk in Communities (ARIC) Study, a prospective study investigating cardiovascular risk factors in approximately 16,000 adults that was initiated in 1986 in four U.S. communities. In one of the communities (Jackson, MS) black participants were recruited exclusively; in another (Forsyth County, NC) 12% of the eligible sample were black, whereas the samples in Washington County, MD and the northwestern suburbs of Minneapolis, MN were almost all white. Demographic and health characteristics were collected during a home interview. Subjects who subsequently agreed to complete a clinical examination were defined as respondents, while eligible participants who only took part in the home interview were considered to be nonrespondents. Approximately 75% of age-eligible individuals (45-64 years) in each community completed the home interview. In three of the communities 86-88% of those who took part in the home interview also completed the clinic examination, whereas only 65% did so in Jackson. Among white participants, response rates were similar in men and women and between communities. Among black participants, the response rates were considerably lower, particularly in men. White male respondents reported a higher socioeconomic status, better general health and a lower prevalence of cardiovascular disease and associated risk factors than white male nonrespondents. The difference between white respondents and nonrespondents were greater for men than women despite similar response rates. Among black participants, respondent/nonrespondent difference were usually of smaller magnitude or absent, particularly in women. General health status and recent hospitalization rates were almost identical in black respondents and nonrespondents. Low response rates can bias estimates of prevalence in community-based studies although differences between respondents and nonrespondents tend to exaggerate real differences between respondents and the eligible population sampled. For example, among white males 25% of respondents and 44% of nonrespondents were current smokers, yet the estimated community prevalence of smoking was 31%. In conclusion, difference observed between respondents and nonrespondents were in the expected direction, but were greater for men than women and for whites than blacks.

Bias↗
PubMed1996

Perinatal mortality in twins and singletons matched for gestational age at delivery at > or = 30 weeks.

OBJECTIVE: Our purpose was to compare perinatal mortality between twins and singletons matched for gestational age at delivery with the hypothesis that perinatal mortality would be similar. STUDY DESIGN: A retrospective cohort study compared perinatal mortality in twins (790 babies) matched for gestational age at delivery at > or = 30 weeks with the next singleton. Perinatal mortality was also compared by expected growth (small and average for gestational age) and by the cause of the preterm delivery (medical indication, spontaneous preterm delivery, or preterm premature rupture of membranes with preterm delivery. RESULTS: Uncorrected perinatal mortality was significantly greater in singletons (56/1000) than in twins (26/1000) (p = 0.004). After major congenital anomalies were excluded, perinatal mortality remained significantly higher in singletons (25/1000) than in twins (11/1000) (p = 0.04). In preterm deliveries perinatal mortality was significantly greater in singletons (72/1000) than in twins (19/1000) (p = 0.0002). Perinatal mortality was significantly greater in small- compared with average-for-gestational-age neonates, whether singletons or twins (p = 0.005), and singleton small-for-gestational-age neonates had a significantly greater perinatal mortality (105/1000) than did twin small-for-gestational-age neonates (36/1000) (p = 0.02). Perinatal mortality was not significantly different between preterm singletons and twins delivered by spontaneous preterm labor. However, perinatal mortality in preterm singletons delivered for a medical indication (156/1000) was significantly greater than for twins (20/1000) (p = 0.0006). CONCLUSIONS: At > or = 30 weeks at delivery, twins either had a perinatal mortality similar to, or less than singletons matched for gestational age at delivery. This suggests that when preterm delivery is controlled for perinatal mortality is not greater in twins. In twins, without risk factors for perinatal death, routine antepartum testing may not be indicated.

Birth Weight↗
PubMed1996

A procedure to study unscheduled DNA synthesis in rat spermatogenic cells in vivo: strain differences between Fisher-344 and Sprague-Dawley rats.

A liquid scintillation counting (LSC) procedure was used to study unscheduled DNA synthesis (UDS) in pachytene spermatocytes and spermatids from Fisher-344 (F344) and Sprague-Dawley (SPD) rats treated with methyl methanesulfonate (MMS). MMS induced a large, dose-dependent, UDS response in pachytene spermatocytes from both rat strains. On average, F344 pachytene spermatocytes showed a larger UDS response than those of SPD rats. The lowest dose of MMS that elicited a significant UDS response was 1 mg/kg in F344 rats but 5 mg/kg in SPD rats. Early spermatid stages from F344 rats also showed a larger UDS response than those from SPD rats. The time interval at which spermatid stages showed the maximum UDS response was between 20 and 24 days after MMS treatment. It is concluded that UDS can be measured quantitatively in rat spermatogenic cells in vivo by using the LSC procedure.

Animals↗
PubMed1996

The effect of nonresponse on prevalence estimates for a referent population: insights from a population-based cohort study. Atherosclerosis Risk in Communities (ARIC) Study Investigators.

Characterization of nonrespondents, with the aim of detecting nonresponse bias, is a crucial component of prospective studies. This study was undertaken to investigate the demographic and health characteristics of nonrespondents to a population-based cohort study of cardiovascular disease, to determine whether early-stage nonrespondents differ from late-stage nonrespondents, and to estimate the bias in prevalence estimates for the source population. Sixty-seven percent of eligible subjects completed all phases of the cohort recruitment. Compared to respondents, nonrespondents were less likely to be married, less likely to be employed, and less likely to be well educated. Nonrespondents tended to describe their general health in less favorable terms and were more likely to be smokers. Their reported disease profile, however, was not dissimilar to that of respondents. For several demographic and health characteristics, including marital status, education, and smoking, early-stage nonrespondents differed from respondents more than did late-stage nonrespondents. For example, 42% of early nonrespondents were smokers compared to 37% of late nonrespondents and 22% of respondents. Overall, the bias in prevalence estimates related to nonresponse was small (< 5%) for most of the measured characteristics. Although nonresponse to health surveys is associated with typical attributes, early nonrespondents differ from respondents more than do late-stage nonrespondents. With few exceptions, however, a 33% nonresponse rate did not appear to introduce substantial bias into prevalence estimates for the source community.

Age Distribution↗
PubMed1996

Molecular docking programs successfully predict the binding of a beta-lactamase inhibitory protein to TEM-1 beta-lactamase.

Crystallization of the 1:1 molecular complex between the beta-lactamase TEM-1 and the beta-lactamase inhibitory protein BLIP has provided an opportunity to put a stringent test on current protein-docking algorithms. Prior to the successful determination of the structure of the complex, nine laboratory groups were given the refined atomic coordinates of each of the native molecules. Other than the fact that BLIP is an effective inhibitor of a number of beta-lactamase enzymes (KI for TEM-1 approximately 100 pM) no other biochemical or structural data were available to assist the practitioners in their molecular docking. In addition, it was not known whether the molecules underwent conformational changes upon association or whether the inhibition was competitive or non-competitive. All six of the groups that accepted the challenge correctly predicted the general mode of association of BLIP and TEM-1.

Amino Acid Sequence↗
PubMed1996

Gas leakage and the laryngeal mask airway. A comparison with the tracheal tube and facemask during spontaneous ventilation using a circle breathing system.

The ability of the laryngeal mask airway, tracheal tube and facemask to provide a leak free seal in a clinical setting was assessed by measuring the minimal fresh gas flows needed in a closed circle system during spontaneous ventilation on 60 subjects. The fresh gas flow was reduced until no spillage occurred from the pop-off valve. This fresh gas flow was taken to represent the sum of gas uptake by the subject and gas leakage from the circuit. The median fresh gas flow after 20 minutes was 350 ml.min-1 in the laryngeal mask airway group, 350 ml.min-1 in the tracheal tube group and 450 ml.min-1 in the facemask group. The fresh gas flow required for the facemask group was significantly higher than that for the laryngeal mask airway or tracheal tube groups (p < 0.01). There was no significant difference between the fresh gas flows required for the tracheal tube and laryngeal mask airway group. We conclude that the laryngeal mask airway provides as good a gas tight seal as a tracheal tube in this context and would be of benefit in reducing anaesthetic gas pollution.

Adult↗
PubMed1996

An evaluation of an antiadhesive copolymer agent on plaque inhibition by chlorhexidine.

The high molecular weight copolymer M239144 has proven antiadhesive action in vitro but clinically lacked effect, even when combined with chlorhexidine. This latter result was thought to arise from inactivation of chlorhexidine by the copolymer. The aim of this study was to determine whether improved activity might arise if the copolymer and chlorhexidine were applied sequentially rather than combined. The study was a double-blind, randomised crossover design balanced for carryover using a 24-h plaque regrowth method. 2 groups of 25 subjects from a zero plaque baseline rinsed 1x with 15 ml volumes of the allocated paired rinses for 60 s. Subjects abstained from toothcleaning for 24 h and were scored for plaque by area. The paired regimens were: 1. placebo: placebo; 2. placebo: 0.03% chlorhexidine; 3. 1% co-polymer and 0.03% chlorhexidine; 4. placebo: 1% co-polymer; 5. placebo: 0.12% chlorhexidine. Plaque regrowth was greatest with regimen 1 and least with regimen 5. However, regimens 3 and 4 were not significantly different from regimen 1, whereas regimen 2 was significantly more effective than regimen 3. The results indicate that the copolymer alone is ineffective, and even delivered sequentially, inactivates chlorhexidine.

Anti-Infective Agents, Local↗
PubMed1996

Community acquired pneumonia: aetiology and usefulness of severity criteria on admission.

BACKGROUND: Community acquired pneumonia remains an important cause of hospital admission and carries an appreciable mortality. Criteria for the assessment of severity during admission have been developed by the British Thoracic Society (BTS). A study was performed to determine the sensitivity and specificity of a severity rule based on a modification of the BTS prognostic rules applied on admission, to compare severity as assessed by medical staff with the modified rule, and to determine the microbiological cause of community acquired pneumonia in Christchurch. METHODS: A 12 month study of all adults admitted to Christchurch Hospital with community acquired pneumonia was undertaken. Three hundred and sixteen consecutive patients with suspected community acquired pneumonia were screened for inclusion. Variables obtained from the history, examination, investigations, and initial treatment were examined for association with mortality. RESULTS: Two hundred and fifty five patients met the inclusion criteria. Their mean age was 58 years (range 18-97). A microbiological diagnosis was made in 181 cases (71%), Streptococcus pneumonia (39%), Mycoplasma pneumoniae (16%), Legionella species (11%), and Haemophilus influenzae (11%) being the most commonly identified organisms. Patients had a 36-fold increased risk of death if any two of the following were present on admission: respiratory rate > or = 30/min, diastolic BP < or = 60 mm Hg, urea > 7 mmol/l, or confusion. The severity rule identified 19 of the 20 patients who died and six of eight patients admitted to the intensive care unit as having life threatening community acquired pneumonia. The sensitivity of the modified rule for predicting death was 0.95 and the specificity 0.71. In 47 cases (21%) the clinical team appeared to underestimate the severity of the illness. CONCLUSIONS: The organisms responsible for community acquired pneumonia in Christchurch are similar to those reported from other centres except for Legionella species which were more common than in most studies. The modification of the BTS prognostic rules applied as a severity indicator at admission performed well and could be incorporated into management guidelines.

Adolescent↗
PubMed1996

Apparatus for studying behavior and learning in restrained rats.

A new treadmill/stand apparatus for a rat is described. It will be useful in behavioral experiments when control of the animal's position in the training chamber is required while considerable freedom of movement, including locomotion, is desired. The position and distance relative to sources of stimuli are thus kept constant. The speed and the distance of ambulation are easily monitored. The rats are sufficiently restrained to enable easy recording of various measures such as EKG, EMG or EEG, etc. Classical and instrumental conditioning procedures are easily implemented. An example of the data from acquisition training during Pavlovian conditioning is shown (diaphragm EMG, heart rate (HR), locomotion and vocalization).

Animals↗