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1.
Biol Sport ; 33(3): 251-6, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27601779

ABSTRACT

Olympic weightlifting movements and their variations are believed to be among the most effective ways to improve power, strength, and speed in athletes. This study investigated the effects of two Olympic weightlifting variations (hang cleans and hang snatches), on power (vertical jump height), strength (1RM back squat), and speed (40-yard sprint) in female collegiate athletes. 23 NCAA Division I female athletes were randomly assigned to either a hang clean group or hang snatch group. Athletes participated in two workout sessions a week for six weeks, performing either hang cleans or hang snatches for five sets of three repetitions with a load of 80-85% 1RM, concurrent with their existing, season-specific, resistance training program. Vertical jump height, 1RM back squat, and 40-yard sprint all had a significant, positive improvement from pre-training to post-training in both groups (p≤0.01). However, when comparing the gain scores between groups, there was no significant difference between the hang clean and hang snatch groups for any of the three dependent variables (i.e., vertical jump height, p=0.46; 1RM back squat, p=0.20; and 40-yard sprint, p=0.46). Short-term training emphasizing hang cleans or hang snatches produced similar improvements in power, strength, and speed in female collegiate athletes. This provides strength and conditioning professionals with two viable programmatic options in athletic-based exercises to improve power, strength, and speed.

2.
J Sports Med Phys Fitness ; 53(2): 162-8, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23584323

ABSTRACT

AIM: Whilst there is growing evidence that physical activity across the lifespan is beneficial for improved health, there are many physiological changes involved with the aging process and subsequently the potential for reduced indices of health. The experimental aim was to gain improved understanding of the nexus between health, physical activity and aging by testing the hypothesis that prevalence of obesity (BMI ≥30 kg/m2) in the World Masters Games swimming cohort would be less than adult national populations. METHODS: Body mass index (BMI) of 527 (49.7% male, 50.3% female) World Masters Games (WMG) swimmers aged 25-91 yrs (mean 54.3, standard deviation ±12.2) was investigated using a survey tool. RESULTS: Analysis demonstrated significantly (χ2=44.9, P<0.001) reduced obesity (9% vs. 21%) when compared to the adult (aged ≥18years) Australian as well as other appropriate national populations. Investigation revealed, amongst other findings, that in line with trends shown in the adult Australian population, WMG male swimmers had a significantly higher BMI (mean 25.9 vs. 24.6) than their female counterparts (Z=-5.8, P<0.001). CONCLUSION: Evidence of improved classification in one index of health (BMI ≥30 kg/m2) for WMG swimmers raised the possibility of improved classification due to adherence to sport or that reduced BMI was advantageous, contributing to this cohort competing at the WMG. This proportionately under-investigated population having reduced obesity over national populations was of particular interest given the obesity epidemic, the multi-faceted approaches taken globally in an attempt to halt this epidemic and a usual tendency for increased incidence of obesity with age.


Subject(s)
Body Mass Index , Swimming/physiology , Adult , Aged , Aged, 80 and over , Australia , Chi-Square Distribution , Competitive Behavior , Female , Humans , Male , Middle Aged , Statistics, Nonparametric
3.
Colorectal Dis ; 13(1): 31-8, 2011 Jan.
Article in English | MEDLINE | ID: mdl-19674021

ABSTRACT

AIM: Colorectal Nurse Specialist (CNS) clinics for postoperative follow up of colorectal cancer aim to maintain clinical efficacy while reducing costs. We prospectively studied the efficacy and financial implications of such a clinic. METHOD: This was a prospective study of all patients attending CNS clinics over 3 years. A lower-risk protocol for patients with Dukes A was used over 3 years and a higher-risk protocol for patients with Dukes B, C or D was used over 5 years. Department of Health Pricing Charts were used to cost the follow-up protocols, and adjustment was performed to calculate the cost of each quality adjusted life year (QALY) gained. RESULTS: One hundred and ninety-three patients entered into this nurse-led follow-up protocol implemented by the CNS clinic between 2005 and 2007. The Dukes stages and proportions of patients in each stage were as follows: stage A, 13%; stage B, 8%; stage C, 36.3%; and stage D, 9.3%. Ninety-seven per cent underwent curative treatment and 2.6% had palliative treatment. Twenty-one per cent of patients developed recurrent disease. Overall actuarial 5-year survival was 80% and recurrences had a 30% 5-year actuarial survival. The total cost per patient for 3 years of follow up was £1506 and £1179 for lower-risk rectal and nonrectal cancers, respectively. The adjusted cost for each QALY gained for lower-risk tumours was £1914. The total cost per patient with higher-risk tumours was £1814 and £1487 for rectal and nonrectal tumours, respectively. The adjusted cost for each QALY gained was £2180 for higher-risk tumours. CONCLUSIONS: This clinic demonstrated cost-effective detection of recurrent disease. Computed tomography (CT) was the most sensitive alert test. As all recurrences were detected within 4 years, we suggest that this is the indicated time to follow up.


Subject(s)
Ambulatory Care Facilities/economics , Colorectal Neoplasms/economics , Colorectal Neoplasms/nursing , Continuity of Patient Care , Colonoscopy , Colorectal Neoplasms/mortality , Cost-Benefit Analysis , Disease Progression , Female , Humans , Male , Neoplasm Recurrence, Local , Neoplasm Staging , Population Surveillance , Prospective Studies , Quality-Adjusted Life Years , Sigmoidoscopy , Specialties, Nursing , Survival Rate , Tomography, X-Ray Computed , Workforce
4.
J Sci Med Sport ; 8(2): 190-9, 2005 Jun.
Article in English | MEDLINE | ID: mdl-16075779

ABSTRACT

It has been forwarded that strength training is the primary intervention for improving and maintaining functional independence of the elderly. The purpose of this study was to determine if a periodised strength-training program was superior to a fixed repetition protocol for enhancing strength in older adults. Previously untrained male and female participants (71.6+/-5.3 y) were separated into three groups: fixed repetition (FR: n= 18), periodised (PER: n= 21) and control (C: n= 21). FR and PER protocols trained 2 days/week performing knee extensions, leg press, leg curl, biceps curl, triceps extension, lat pull downs, shoulder press and seated bench press. FR performed three sets of 9RM/exercise throughout the 18-week study. PER performed two sets of 15RM/exercise (weeks 1-6), three sets of 9RM/exercise (weeks 7-12) and four sets of 6RM/exercise (weeks 13-18). Pre-post 1RM were collected for each exercise. The sum of 1RM for the eight exercises was considered indicative of total body strength and served as the dependent variable. An ANOVA with Bonferroni post hoc was utilised to analyse the data. FR (p< 0.01) and PER (p< 0.01) groups experienced significant strength gains compared to C but were not different from each other. The results suggest that previously untrained older adults could expect similar strength gains from FR or PER strength-training protocols of 18 weeks or less.


Subject(s)
Muscle, Skeletal/physiology , Physical Education and Training/methods , Aged , Aged, 80 and over , Analysis of Variance , Female , Humans , Male , Middle Aged , Physical Endurance , Time Factors , Treatment Outcome
5.
J Sci Med Sport ; 6(4): 387-97, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14723389

ABSTRACT

Previous investigations reported alterations in myocardial fibres and systolic function associated with anabolic-androgenic steroid consumption by athletes. Advances in bio-medical technology have allowed further investigation in assessing the possible effects of anabolic-androgenic steroids on gross left ventricular kinetics. Twenty-three male strength and power athletes with a past and current history of anabolic-androgenic steroid consumption (x 46 days, range 28 days to 70 days), were compared to 23 controls. Testing consisted of resting and immediate post-exercise transthoracic left ventricular wall cardiokymograms. Statistical results identified no difference over time between groups or condition. Cardiokymographic waveform analysis found 32.61% of all (n =184) waveforms to be abnormal (Type II, n = 56 or Type III, n = 4). There were 14 treatment subjects (60.87%) who demonstrated an abnormal waveform as compared to 9 controls (39.13%). A significant difference (p < or = 0.01) in the overall proportions of waveform types was identified where the treatment group exhibited 41.30% abnormal waveforms, compared to 23.91% by controls. Additionally, two athletes (1 treatment, 1 control) demonstrated abnormal left ventricular wall motions (Type III) analogous to impaired left ventricular performance. The results indicated: (a) highly strength trained athletes with no history of anabolic-androgenic steroid usage exhibited an unexpected high incidence of Type II waveforms (28.26% pre/23.91% post); (b) a comparable group of strength trained athletes using anabolic-androgenic steroids exhibited a significantly higher percentage of abnormal waveforms as compared to controls (34.78% pre/37.21% post). Based on these results, high intensity strength training with and without anabolic-androgenic steroid supplementation induced alterations in the left ventricular wall motion.


Subject(s)
Anabolic Agents/pharmacology , Androgens/pharmacology , Exercise/physiology , Rest/physiology , Steroids/pharmacology , Ventricular Function, Left/drug effects , Adult , Body Weight/drug effects , Humans , Kinetics , Male , Myocardial Contraction/drug effects , Sports/physiology
6.
Med Vet Entomol ; 16(1): 106-8, 2002 Mar.
Article in English | MEDLINE | ID: mdl-11963974

ABSTRACT

Adult mosquitoes, Anopheles gambiae Giles and Culex quinquefasciatus Say (Diptera: Culicidae), were exposed for 3 min to replicate samples of polyester netting cut from replicate bednets treated with pyrethroid insecticide formulations at the recommended concentration (alphacypermethrin SC at 40mg ai/m2; cyfluthrin EW at 50 mg ai/m2; deltamethrin WT at 25 mg ai/m2), or treated with only a quarter of those dosages. After 4 months domestic use of the bednets in Malawi, chemical assays showed that pyrethroid deposits on the netting were somewhat less than the target concentrations. Comparing the pyrethroid bioassay results with Anopheles at both treatment concentrations, deltamethrin gave significantly higher mortality (99.7-100%) than the other compounds (alphacypermethrin 94-96%, cyfluthrin 80-89%). Culex bioassay mortality was lower (alphacypermethrin 56-74%; cyfluthrin 63-65%; deltamethrin 50-81 %) and results with the three pyrethroid insecticides at their recommended doses did not differ significantly.


Subject(s)
Anopheles/drug effects , Culex/drug effects , Insecticides/pharmacology , Mosquito Control/methods , Pyrethrins/pharmacology , Animals , Beds , Dose-Response Relationship, Drug , Female , Male , Survival Analysis
7.
J Strength Cond Res ; 15(3): 302-8, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11710655

ABSTRACT

This study determined the reliability and validity of a branching treadmill protocol in predicting VO2max. Thirty-seven, apparently healthy individuals (19 women and 18 men); volunteered to participate. On 2 separate testing days, each subject underwent maximal exercise testing using the protocol developed. Stepwise regression analysis indicated that the percentage of age-predicted maximum heart rate (APMHR) achieved at stage 3, speed and grade at stage 3, and APMHR accounted for 89% of the variance in VO2max. The 4 predictor variables were statistically significant (p < 0.01), and the standard error of the estimate was 4.56 ml x kg(-1) min(-1). Results indicate that health and fitness professionals can incorporate this protocol into their practices for the purpose of predicting VO2max for their clients outside the laboratory environment. Furthermore, our results indicate that using the proposed regression model is reliable and has received preliminary construct validity support.


Subject(s)
Exercise Test/methods , Oxygen Consumption/physiology , Adult , Analysis of Variance , Female , Heart Rate/physiology , Humans , Male , Predictive Value of Tests , Regression Analysis , Reproducibility of Results
8.
J Strength Cond Res ; 15(1): 123-6, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11708695

ABSTRACT

Inadequate flexibility is a contributing factor to muscle injury, especially with respect to the hamstring muscle group. Simple therapeutic regimens capable of increasing hamstring flexibility may reduce the injury potential of athletes with below-average hamstring flexibility or history of injury. This study compared 30 seconds of static stretching with 20 minutes of heat application on hamstring flexibility. A secondary purpose was to determine the relationship between the subjects attitude toward each treatment and the efficacy of treatment. Thirty undergraduate student athletes who were current members of a Midwestern collegiate football team participated in a 2 (treatment: heat vs. stretching) by 2 (coun-terbalanced order: heat first vs. stretching first) repeated-measures design. Results indicated that significant benefits to increase hamstring flexibility could be gained by using moist heat packs in comparison with static stretching despite a perceived attitudinal bias in favor of stretching. These findings may have implications for orthopedic fitness as well as injury prevention for an athlete with prior hamstring injury or inadequate flexibility.


Subject(s)
Leg/physiology , Muscle, Skeletal/physiology , Physical Education and Training/methods , Adolescent , Adult , Attitude to Health , Hot Temperature/therapeutic use , Humans , Male , Pliability , Sports/physiology , Sports/psychology
9.
Med Sci Sports Exerc ; 33(9): 1567-76, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11528347

ABSTRACT

PURPOSE: This study investigated effects of an 8-wk, low-frequency and low-volume, supervised, progressive strength training program emphasizing free weight, multijoint movements on the muscular power, strength, endurance, and flexibility of African American women 44 to 68 yr of age. METHODS: Nineteen sedentary African American women were randomly assigned to a strength training (ST) only group (N = 12; mean age, 51 yr) or a nonexercise control (C) group (N = 7; mean age, 52 yr). Maximal power, strength, absolute endurance, and flexibility were assessed before and after training. Subjects trained 2 d x wk(-1) using free weight (barbells and dumbbells) and machine (plate loaded) exercises for two to three sets of 8 to 10 repetitions on both primary and assistance exercises. RESULTS: Upper body power (medicine ball put distance) significantly increased statistically (P = 0.002), but gains possibly lacked practical significance because of measurement variation. Lower body power (peak watts on bicycle) experienced a small, nonsignificant increase in the ST group. Significant increases (P = 0.000) in 1RM muscle strength occurred in the ST group (leg press, +99.8%; bench press, +34.4%). Absolute endurance significantly increased (P = 0.000) in the ST group (leg press repetitions to failure at 70% pretest 1RM, +221%; bench press repetitions to failure at 50% pretest 1RM, +112%). Significant flexibility gains occurred in the ST group (sit-and-reach test, +8.2%; P = 0.017). No significant changes occurred in power, strength, absolute endurance, or flexibility in the C group. CONCLUSION: This study demonstrates that 8 wk of low-frequency, supervised, progressive strength training emphasizing free weight, multijoint movements can safely cause significant gains in muscle strength, absolute endurance, and flexibility in older African American women.


Subject(s)
Black People , Physical Endurance , Weight Lifting , Adult , Aged , Aging/physiology , Female , Humans , Middle Aged , Muscle, Skeletal/physiology , Pliability , Range of Motion, Articular , Women's Health
10.
J Cardiopulm Rehabil ; 19(6): 366-72, 1999.
Article in English | MEDLINE | ID: mdl-10609187

ABSTRACT

PURPOSE: The safety of one repetition maximum (1RM) testing for patients with chronic obstructive pulmonary disease (COPD) has not been determined. Therefore, this study was conducted to determine the prevalence of abnormal cardiopulmonary responses, muscle soreness, and muscle injury of patients with moderate to severe COPD in response to 1RM testing. METHODS: Twenty pulmonary rehabilitation patients (11 women and 9 men) with moderate or severe COPD participated in this investigation. The 1RM testing was performed using the parallel squat and incline press. Blood pressure, heart rate dyspnea ratings, and oxygen saturation responses were measured immediately following the 1RM procedure. Ratings of muscle soreness and injury were measured immediately after 1RM testing and on days 2 and 7. RESULTS: No injury, significant muscle soreness, or abnormal cardiopulmonary responses occurred as a result of 1RM testing. No gender differences were found for any variable measured in response to 1RM testing. CONCLUSIONS: A properly supervised and screened pulmonary rehabilitation population can be 1RM tested without significant muscle soreness, injury, or abnormal cardiopulmonary responses.


Subject(s)
Exercise Therapy/methods , Lung Diseases, Obstructive/rehabilitation , Activities of Daily Living , Aged , Blood Pressure , Female , Heart Rate , Humans , Lung Diseases, Obstructive/physiopathology , Male , Middle Aged , Muscle, Skeletal/pathology , Oxygen/blood
11.
J Cardiopulm Rehabil ; 19(4): 209-15, 1999.
Article in English | MEDLINE | ID: mdl-10453427

ABSTRACT

BACKGROUND: Developing adequate levels of muscular strength in the cardiac rehabilitation (CR) patient helps return the patient to an active lifestyle. This study evaluated the effects and safety of an 8-week high-intensity strength training (ST) program combined with a traditional aerobic-based CR program on the muscular strength of a diverse phase II CR population. METHODS: Sixty-one phase II CR patients (age = 60.5 +/- 10.6 years) stratified by risk (high risk: n = 18, ejection fraction = 23.6 +/- 7.8%; intermediate risk: n = 19, ejection fraction = 40.0 +/- 4.6%; low risk: n = 24, ejection fraction = 58.0 +/- 7.7%) and gender (males = 46, females = 15) participated. One repetition maximum (1RM) testing was performed on the horizontal squat, shoulder press, leg extension, lat pulldown, and biceps curl. Patients performed two sets of each exercise 2 days per week at an intensity that started at 60% 1RM and progressed to 80% 1RM by week 4. Weeks 4 to 8 intensity was adjusted individually to maintain 8RM per set. Blood pressure and heart rate/rhythm responses to 1RM testing were monitored in high-risk patients. Muscle soreness and injury were monitored for all patients immediately after 1RM testing and on days 2 and 7. RESULTS: All patient groups made significant gains (P < 0.05) in muscle strength (mean increase: lower body = 15.3%, upper body = 16.7%). No injury or significant muscle soreness occurred due to 1RM testing. No abnormal heart rate/rhythm or blood pressure responses occurred in high-risk patients. CONCLUSIONS: Diverse phase II CR patients can improve their strength significantly with a combination of high-intensity strength and aerobic training.


Subject(s)
Exercise Therapy/methods , Exercise/physiology , Heart Diseases/rehabilitation , Muscle, Skeletal/physiology , Electrocardiography , Female , Follow-Up Studies , Heart Diseases/diagnosis , Heart Diseases/physiopathology , Humans , Male , Middle Aged , Safety , Severity of Illness Index , Stroke Volume , Treatment Outcome
12.
J Cardiopulm Rehabil ; 19(1): 52-8, 1999.
Article in English | MEDLINE | ID: mdl-10079421

ABSTRACT

BACKGROUND: Strength training (ST) may be beneficial for preservation of lean tissue, increasing bone mineral content, decreasing falls, and enhancing quality of life. Strength training is becoming an appropriate mode of exercise for cardiac rehabilitation (CR) patients. One method for determining optimal exercise intensity for safe and effective ST requires one repetition maximum (1RM) testing. Clinicians may be reluctant to perform 1RM testing in CR patients because of potential muscle soreness/injury and adverse hemodynamic responses in deconditioned patients. The purpose of this investigation was to perform 1RM testing in CR patients and determine muscle soreness/injury rate. METHODS: Seventy-four CR patients stratified by risk (low n = 30, intermediate n = 21, high n = 23) and sex (males = 55, females = 19) participated. Subject's ages ranged from 39 to 76 years and time from procedure ranged from 19 days to 2 years. No patient had ever undergone 1RM testing. The method of Kraemer and Fry was used to assess 1RM. High-risk patients' heart rates/rhythms and blood pressures were monitored. Patients were evaluated for occurrence of muscle soreness/injury immediately after 1RM testing and on days 2 and 7 using a soreness scale developed by Shaw et al. Muscle soreness/injury was considered significant if a patient reported altering or stopping physical activities. RESULTS: No injury or significant muscle soreness occurred as a result of 1RM testing. No abnormal heart rate/rhythm or blood pressure responses occurred in high-risk patients. CONCLUSIONS: Results indicate that with proper technique, 1RM testing may be performed in CR patients without injury or significant muscle soreness.


Subject(s)
Exercise Therapy/adverse effects , Heart Diseases/rehabilitation , Pain/etiology , Weight Lifting , Wounds and Injuries/etiology , Adult , Aged , Blood Pressure , Exercise Therapy/methods , Female , Heart Rate , Humans , Male , Middle Aged , Muscle, Skeletal , Risk Factors
13.
Hum Genet ; 94(2): 141-8, 1994 Aug.
Article in English | MEDLINE | ID: mdl-8045560

ABSTRACT

A locus (CPX) responsible for X-linked cleft palate and ankyloglossia was previously mapped to the proximal long arm of the X chromosome through DNA marker linkage studies in two large kindred: an Icelandic family and a British Columbia (B.C.) Native family. In this study, additional linkage analyses have been performed in the B.C. family and in a newly identified Manitoba Mennonite family with X-linked cleft palate and ankyloglossia. The Manitoba CPX locus maps to the same region as Icelandic and B.C. CPX. Two-point disease-to-marker linkage analyses in the Manitoba family indicate a maximum lod score (Zmax) between CPX and DXS349 (Zmax = 3.33 at theta = 0.0). In multipoint linkage analysis, combined data from the B.C. and Manitoba families suggest that the most likely location for CPX is at DXS447 in Xq21.1 (multipoint Z = 13.5). The support interval for CPX at DXS447 extends approximately from PGK1 to DXYS1 and includes a newly isolated polymorphic locus DXS1109.


Subject(s)
Cleft Palate/genetics , Genetic Linkage , Indians, North American/genetics , Tongue/abnormalities , X Chromosome , Autoradiography , British Columbia , Cleft Palate/ethnology , Female , Genetic Markers , Genotype , Humans , Lod Score , Male , Manitoba , Pedigree
14.
Am J Hum Genet ; 50(5): 1129-36, 1992 May.
Article in English | MEDLINE | ID: mdl-1570839

ABSTRACT

Human craniofacial malformations are a class of common congenital anomalies in which the etiology is heterogeneous and often poorly understood. To better delineate the molecular basis of craniofacial development, we have undertaken a series of experiments directed toward the isolation of a gene involved in human secondary palate formation. DNA marker linkage studies have been performed in a large British Columbia (B.C.) Native family in which cleft palate segregates as an X-linked trait. We have examined 62 family members, including 15 affected males and 8 obligate carrier females. A previous clinical description of the clefting defect in this kindred included submucous cleft palate and bifid or absent uvula. Our recent reevaluation of the family has indicated that ankyloglossia (tongue-tie) is also a feature of X-linked cleft palate in some of the affected males and carrier females. Ankyloglossia has previously been associated with X-linked cleft palate in an Icelandic kindred in which a gene responsible for cleft palate (CPX) was assigned to the Xq21.3-q22 region between DXYS12 and DXS17. For the B.C. kindred reported here, we have mapped the gene responsible for cleft palate and/or ankyloglossia to a more proximal position on the X chromosome. No recombination was observed between B.C. CPX and the DNA marker DXS72 (peak lod score [Zmax] = 7.44 at recombination fraction [theta] = .0) localized to Xq21.1. Recombination was observed between CPX and PGK1 (Zmax = 7.35 at theta = .03) and between CPX and DXYS1 (Zmax = 5.59 at theta = .04). These recombination events localize B.C. CPX between PGK1 and DXYS1 in the Xq13-q21.31 region.


Subject(s)
Cleft Palate/genetics , Genetic Linkage/genetics , X Chromosome , Blotting, Southern , Female , Genetic Markers/genetics , Heterozygote , Humans , Male , Pedigree , Polymorphism, Genetic/genetics , Tongue/abnormalities
15.
Carcinogenesis ; 8(5): 729-31, 1987 May.
Article in English | MEDLINE | ID: mdl-3581431

ABSTRACT

The mainstream and sidestream smoke of four types of popular US cigarettes were analyzed for toxic and carcinogenic agents. The cigarettes included one without a filter tip, and one filter cigarette each with medium, low and ultra-low smoke yields. The analyses clearly demonstrated that 12 toxic agents determined in this study were significantly reduced in the mainstream smoke of filter cigarettes, as compared with smoke yields from the nonfilter cigarette. In the case of the ultra-low yield cigarette, mainstream smoke emissions were reduced by about 90%. In contrast to this finding, the emissions of the same toxic and carcinogenic components into sidestream smoke of the filter cigarettes were not greatly reduced. Sidestream smoke is the major contributor to environmental tobacco smoke, to which both smokers and non-smokers are exposed. Although the exposure of the smoker to mainstream smoke components is decreased due to proportionally greater consumption of low and ultra-low yield cigarettes, and lower rates of consumption of cigarettes with high smoke yields, the carcinogenic potential of indoor pollutants originating from tobacco products is not diminished.


Subject(s)
Carcinogens/analysis , Nicotiana , Plants, Toxic , Smoke/analysis , Ammonia/analysis , Benzo(a)pyrene/analysis , Carbon Monoxide/analysis , Hydrogen-Ion Concentration , Nicotine/analysis , Nitrosamines/analysis , Tars/analysis
17.
Cancer Lett ; 28(2): 195-201, 1985 Sep 15.
Article in English | MEDLINE | ID: mdl-4052989

ABSTRACT

The pharmacokinetics of N'-nitrosonornicotine (NNN) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) in the Syrian golden hamster, the CD-1 mouse, and the baboon were compared to the pharmacokinetics in the Fischer rat. The formation and biological half-life of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), the major metabolite of NNK, was also studied in these animal species. The biological half-life of NNN in these 4 animal species ranged from 0.24 h to 3.06 h, that of NNK from 0.21 h to 0.43 h and NNAL from 0.48 h to 2.9 h. The pharmacokinetic data obtained in the baboon suggest that treatment with NNN and NNK causes an enzyme induction which accelerates the rate of elimination of these compounds.


Subject(s)
Carcinogens/metabolism , Nitrosamines/metabolism , Animals , Cricetinae , Half-Life , Kinetics , Male , Mesocricetus , Mice , Mice, Inbred Strains , Papio , Rats , Rats, Inbred F344 , Species Specificity
18.
Cancer Res ; 45(4): 1669-73, 1985 Apr.
Article in English | MEDLINE | ID: mdl-3978635

ABSTRACT

The mouse bone marrow has been used as a model for the investigation of the response of cells to cytotoxins and carcinogens. The effects of cyclophosphamide, 1-beta-D-arabinofuranosylcytosine, and X-irradiation on the levels of glutathione and glutathione transferases have been studied. A high dose of cyclophosphamide (500 mg/kg) caused a significant depletion of glutathione levels in marrow, liver, and blood. A lower dose, 75 mg/kg, caused a similar depletion but only in marrow and liver. In this case, 5 to 7 days following treatment, the glutathione content of surviving cells was 1.8- to 3-fold higher than in controls. Glutathione transferase activity was also increased at this time (2- to 3-fold). 1-beta-D-Arabinofuranosylcytosine and X-irradiation also caused a depletion of marrow glutathione and glutathione transferase levels followed increased cellular levels (approximately 2-fold) 3 to 4 days later. Animals given cyclophosphamide (75 mg/kg) survived an otherwise lethal dose of this compound administered 5 to 7 days later. The time course of this effect closely paralleled the higher glutathione and glutathione transferase levels, suggesting a correlation between these effects.


Subject(s)
Antineoplastic Agents/toxicity , Bone Marrow/drug effects , Glutathione Transferase/analysis , Glutathione/analysis , Animals , Bone Marrow/analysis , Cyclophosphamide/toxicity , Cytarabine/toxicity , Dose-Response Relationship, Drug , Male , Mice , Mice, Inbred CBA
19.
Science ; 211(4486): 1002-13, 1981 Mar 06.
Article in English | MEDLINE | ID: mdl-7008196

ABSTRACT

The cell division cycle of both mammalian cells and microorganisms, which apparently has both deterministic and probabilistic features, is a clock of sorts in that the sequence of events that comprise it measures time under a given set of environmental conditions. The cell division cycle may itself be regulated by a programmable clock that, under certain conditions, can generate circadian periodicities by interaction with a circadian pacemaker. These clocks must insert time segments into the cell division cycle in order to generate the observed variability in cellular generation times.


Subject(s)
Biological Clocks , Cell Cycle , Animals , Circadian Rhythm , DNA Replication , Light , Mitosis , Periodicity , Probability
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