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Biomedical subjects

M H Stone

Publications and source records attributed to M H Stone.

At least 19 recordsLinked to original sources
PubMed1992

Acute hormonal responses in elite junior weightlifters.

To date, no published studies have demonstrated resistance exercise-induced increases in serum testosterone in adolescent males. Furthermore, few data are available on the effects of training experience and lifting performance on acute hormonal responses to weightlifting in young males. Twenty-eight junior elite male Olympic-style weightlifters (17.3 +/- 1.4 yrs) volunteered for the study. An acute weightlifting exercise protocol using moderate to high intensity loads and low volume, characteristic of many weightlifting training sessions, was examined. The exercise protocol was directed toward the training associated with the snatch lift weightlifting exercise. Blood samples were obtained from a superficial arm vein at 7 a.m. (for baseline measurements), and again at pre-exercise, 5 min post-, and 15 min post-exercise time points for determination of serum testosterone, cortisol, growth hormone, plasma beta-endorphin, and whole blood lactate. The exercise protocol elicited significant (p less than or equal to 0.05) increases in each of the hormones and whole blood lactate compared to pre-exercise measures. While not being significantly older, subsequent analysis revealed that subjects with greater than 2 years training experience exhibited significant exercise-induced increases in serum testosterone from pre-exercise to 5 min post-exercise (16.2 +/- 6.2 to 21.4 +/- 7.9 nmol.l-1), while those with less than or equal to 2 years training showed no significant serum testosterone differences. None of the other hormones or whole blood lactate appear to be influenced by training experience.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

Performance measures, blood lactate and plasma ammonia as indicators of overwork in elite junior weightlifters.

The effects of short-term overwork on performance measures, blood lactate, and plasma ammonia concentrations were examined in 28 elite junior weightlifters who participated in a 2 wk high volume resistance training camp. Performance testing (maximum effort vertical jump test and snatch lift) and blood chemistry analyses (ammonia and lactate) were conducted before (T1) and after (T2) 7 d of high volume training (2-3 workouts/d). Blood samples were collected from an antecubital vein at rest, preexercise, 5 min postexercise, and 15 min postexercise at T1 and T2. Results indicated a significant decrease from T1 to T2 in the maximum effort vertical jump test while the snatch lift test yielded no difference across time. Blood lactate and ammonia concentrations were significantly lower at 5 min postexercise at T2 while resting ammonia concentrations were significantly elevated at T2 compared to corresponding measures at T1. These data suggest possible early symptoms of overwork at T2 (decrease in performance of the maximum effort vertical jump test and the elevated resting ammonia concentrations); however, lower 5 min postexercise concentrations of lactate and ammonia at T2 indicated a positive adaptation to the 1 wk high volume resistance training period.

Adolescent↗
PubMed1992

Efficacy of chromium supplementation in athletes: emphasis on anabolism.

As the biologically active component of glucose tolerance factor (GTF), the essential trace mineral chromium is now being marked to athletes. GTF potentiates insulin activity and is responsible for normal insulin function. Thus, insulin's effects on carbohydrate, fat, and protein metabolism are dependent upon the maintenance of adequate chromium stores. Due to excessive chromium loss and marginal chromium intake, athletes may have an increased requirement for chromium. Therefore, in some circumstances the dietary supplementation of a chromium compound may be efficacious. The restoration and maintenance of chromium stores via supplementation would promote optimal insulin efficiency, necessary for high-level athletic performance. However, potential anabolic effects of enhanced insulin function would likely be marginal, and reports of short-term anabolic increases from the supplementation of an organic chromium compound need to be confirmed.

Animals↗
PubMed1992

Incest, Freud's seduction theory, and borderline personality.

In the early 1890s Freud expressed the belief that many cases of hysteria had a basis in childhood incest. Later he expressed a different view, emphasizing childhood fantasies of sexual intimacies with a parent that never actually took place. Freud never totally repudiated his original seduction theory, however, maintaining to the end of his life that at least some cases of actual incest occurred and that these instances underlay certain types of psychopathology. In our era we have become aware that incest is frequently a forerunner of subsequent borderline disorders, especially in women hospitalized with borderline personality disorder (B.P.D.). All the clinical manifestations of B.P.D. can be related to the prior incest experiences.

Battered Child Syndrome↗
PubMed1991

Short stem in Charnley low-friction arthroplasty--a review of 100 cases.

One hundred cases of the Charnley low-friction arthroplasties using shorter (75-110 mm) than standard length stems, both in primary and revision surgery were reviewed. The average follow up was five years and three months. Eleven had cortical thickening that could be attributed to the predicted increase in the stresses within the femoral cortex. There were no cases of cortical thickening when the stem was 100 mm or longer. One stem in the 80-84 mm group was revised for loosening. The findings suggest that other than cortical thickening, which has not progressed during the period of the follow-up, there is no need to fear the use of shorter stems if indicated for technical reasons and provided good stem fixation can be achieved.

Adult↗
PubMed1991

Health- and performance-related potential of resistance training.

Regular physical activity can improve cardiovascular fitness and may reduce the likelihood and debilitating effects of cardiovascular disease. Weight-training has generally been believed to have limited value in modifying risks of cardiovascular disease. Effects shown of resistance training on parameters associated with cardiovascular fitness and disease include: heart rate decreases for maximal work and recovery from short term weight-training, increased ventricular mass, and increased ventricular wall and septum thickness. Studies suggest that myocardial hypertrophy resulting from resistive training can be accompanied by positive myocardial adaptations. Blood pressure response considerations to resistive training include: similarity of resistive exercise peak response to other forms of high intensity exercise, highest blood pressures occur at or near exhaustion during maximum lifts, training appears to reduce the exercise blood pressure. Given the blood pressure responses caution is required for individuals with cardiovascular disease. Studies of high-volume weight-training indicate that small to moderate increases in aerobic power can occur in relatively short periods of time. The mechanisms by which weight-training increases VO2max is unclear. Resistive training may produce positive changes in serum lipids with the volume of training being the dependent factor. Cross-sectional and longitudinal studies of bodybuilders suggest that weight-training may beneficially alter glucose tolerance and insulin sensitivity. It appears that weight-training can increase short term high intensity endurance without a concomitant loss in performance. Resistive training increases power output and performance. Body composition has important relationships to cardiovascular fitness, strength and flexibility. It is likely that it can be affected and controlled by use of large body mass during exercise depending on training volume.

Cardiovascular Physiological Phenomena↗
PubMed1991

Variation in applied force during insertion of cemented femoral prostheses.

Information is presented on forces applied to cemented prostheses during insertion. An instrumented femoral pusher was used to collect information during simulated operations on cadavers while using a laboratory test rig and during live surgery. Surgeons using flanged or collared prostheses tend to apply more force than those using collarless prostheses. There is a tendency for abrupt changes in applied force to occur when: 1) clearing cement; 2) easing hand discomfort; and 3) testing cement consistency. Tests showed that an overall impression of the force applied could be obtained from a laboratory simulation, but that clearing cement and testing cement were not modelled by this method. We discuss the implications of our observations in terms of prosthesis fixation and training of staff.

Biomechanical Phenomena↗
PubMed1990

Comparison of audible sound transmission with ultrasound in screening for congenital dislocation of the hip.

In a comparative study ultrasound and the sound transmission test were used to seek congenital dislocation of the hip in 102 babies referred to a paediatric orthopaedic clinic. The sound transmission test correctly identified all those hips considered normal or dislocated on ultrasound. 17 babies underwent repeated ultrasound examination for hips considered abnormal but not dislocated. 12 improved and 5 required treatment. With a cut-off decibel difference between the hips of 5.8 dB the sound transmission test correctly identified the dislocated hips but did not detect some of the hips that needed treatment. A cut-off of 5.6 dB reduced the likelihood of a false-negative result while maintaining the sensitivity of the test.

Analysis of Variance↗
PubMed1990

Anatomical distribution of soft tissue sepsis sites in intravenous drug misusers attending an accident and emergency department.

Of 77,686 case records of attendance at an accident and emergency department during 1986, 488 (0.6%) contained documented evidence of intravenous drug misuse (IDM). Clinical examination had revealed signs of soft tissue sepsis in 150 (31%) of these, the commonest sites being the wrist and forearm (31% of lesions), the antecubital fossa (19%), fingers and hand (14%) and thigh and groin (11%). These data highlight the anatomical areas to which medical and nursing staff should pay particular attention when examining patients with a background of IDM. Conversely, the presentation of soft tissue sepsis in these sites should alert clinicians to the possibility of underlying IDM.

Abscess↗
PubMed1990

Physiological responses to resistance-exercise in athletes self-administering anabolic steroids.

Endocrine and metabolic responses to resistance exercise were compared in 5 athletes self-administering (SL) anabolic steroids and 8 athletes (L) not using these compounds. Exercise consisted of 5 sets of 10 repetitions in the squat and quarter squat. Blood samples were collected before (pre) and immediately after (post) exercise, and following 30 minutes of recovery (post-30). Except for significantly lower lactate concentrations in SL (p less than 0.015) at post-30, the responses to exercise and recovery were similar in both groups. Significantly higher hematocrits (p less than 0.0001), total androgen concentrations (p less than 0.0001), and androgen/cortisol ratios (p less than 0.0001) were observed in the SL group across all time periods. Plasma androgen concentrations increased about 22% in SL following exercise, even though plasma LH concentrations were significantly lower (p less than 0.0001) than in L. Plasma ACTH and cortisol concentrations were not significantly affected. Both groups displayed similar endocrine and metabolic responses to an acute bout of resistance exercise. The higher androgen/cortisol ratios and lower plasma lactate concentrations during recovery are two potential factors which may help explain the lower subjective level of fatigue following training sessions often reported by individuals who use anabolic steroids.

Adrenocorticotropic Hormone↗
PubMed1990

Treatment of borderline patients: a pragmatic approach.

Outlined in the preceding sections are what one could call the ABCDs of treating borderline patients. A = analytically informed psychotherapy; B = behavior therapy; C = cognitive therapy; and D = drug therapy. Together they add up to "E": eclectic therapy. In this pragmatic approach, the therapist will assess at the outset (1) amenability to exploratory therapy, but also (2) the need for supportive measures, including education, rehabilitation, and expansion of outside interests, (3) indications for behavioral technics (socially alienating habits, handwashing compulsions, phobias), (4) indications for cognitive measures (conflicts or fears resolvable through rational explanation or logical weighing of alternatives), and (5) indications for pharmacotherapy. All these steps involve the careful weighing of biologic/constitutional, psychodynamic, and, where present, posttraumatic factors, as well as personality assets and habitual problem-solving style. This will help assure against overreliance on a technic that does not fit with the patient's personality and against unwise persistence in a technic that is uncongenial or threatening. Patients already in stable life situations who are seeking help because of life crises may respond well to a brief course of therapy. Borderlines in late adolescence or early adult life, if self-destructive and not yet able to form lasting relationships (or to live contentedly without them), usually require sustained treatment over several years, preferably with the same therapist. Appropriate selection of medications, where indicated, should reduce impulsivity, aggressivity, and psychoticism. This, in turn, will facilitate psychotherapeutic work on maladaptive interpersonal patterns, exaggerated "all-or-none" responses to relatively innocuous stimuli, overpersonalized responses to other people's remarks, and so on. Therapists trained in identical methods will evaluate the same patient in somewhat different ways owing to their differences in personality and perception. This may lead to different sets of priorities and suggests different tactics that are still within the realm of therapeutic efficacy. Those trained primarily in one of the "ABCDs" may have equal success, yet via a different route than the one taken by therapists of a different subspecialty. Borderline patients, perhaps two out of five, often drop out of treatment no matter who the therapist. Yet two out of three patients, if followed long enough, eventually have a good result. One therapist's failure will be his colleague's success, and vice versa. Therapists, to maximize the success of their own efforts, need to be sufficiently steeped in at least one theoretical model of psychopathology/psychotherapy so as not to feel "lost" when confronted by the often bewildering dynamics and symptoms of their borderline patients.(ABSTRACT TRUNCATED AT 400 WORDS)

Borderline Personality Disorder↗
PubMed1990

Muscle conditioning and muscle injuries.

Empirical and objective data suggest that muscle and connective tissue can undergo adaptations to physical training resulting in greater tissue mass and increased maximum tensile strength. These adaptations are especially apparent as a result of load bearing and resistive training. Furthermore, information is presented suggesting that pre-conditioning and in-season muscle conditioning, especially strength training, reduce injuries among athletes. Additionally, a theoretical model of training, "periodization", is offered as a method of increasing performance to maximum or optimal values while reducing overtraining and injury potential. Periodization of training can reduce overtraining potential and injury potential while optimizing performance by variation of volume, intensity, and exercise selection during a training program.

Animals↗
PubMed1989

Intravenous drug misusers presenting to the accident and emergency department of a large teaching hospital. A failure of clinical management?

The records of all 77,686 attendances at or via the accident and emergency department of the Glasgow Royal Infirmary in 1986 were examined. Of these, 488 (0.6%) contained evidence of intravenous drug misuse (IDM). Most (68%) of the 354 attenders were male. The mean age of attenders in both sexes was 22 years. Over half of the presenting conditions were 'surgical' (mainly abscesses), while 'psychiatric' (including explicitly drug-related) conditions comprised about 30%. In almost two-thirds of cases, patients were discharged without specialist follow-up or care. Only 5% were referred for specialist assessment of their drug misuse. About a fifth were admitted. It is argued that these findings appear to represent a serious a serious failure of clinical management requiring an urgent remedy, particularly in the light of the growing problem of HIV transmission in this group.

Adolescent↗