Flight crew physical fitness: a baseline analysis

INTRODUCTION

The purpose of this pilot study was to determine whether flight crew personnel are physically fit in comparison to published standards for the average American adult.

SETTING

The study group consisted of pilots, paramedics and nurses in two similarly configured and geographically located rotor-wing air medical transport programs.

METHODS

A physical fitness assessment of flight crew members was conducted. The results were compared with published standards for average adult males and females (AVG). Percentage of fat in body composition (FM%), aerobic fitness (VO2MAX), muscular endurance (ME), muscular strength (MS) and flexibility (FL) measurements were obtained using accepted testing methods.

RESULTS

The study population consisted of 29 male and 21 female individuals. The following were their mean scores. Males averaged: pFAT = 19% (AVG = 20.0%); VO2MAX = 41.0 (AVG = 42.5); ME = 37.0 (AVG = 28.5); MS = 125.0 (AVG = 86.5); FL = 5.2 (AVG = 1.4); Females averaged: pFAT = 28.0% (AVG = 26.5%); VO2MAX (AVG = 34.0); ME = 27.0 (AVG = 21.0); MS = 83.0 (AVG = 76.5); FL = 4.5 (AVG = 3.4).

CONCLUSION

These baseline data suggest the study population of air medical flight crew was physically fit compared to the average American adult.

Purification and biochemical characterization of recombinant N-methylpurine-DNA glycosylase of the mouse

The mouse N-methylpurine-DNA glycosylase (MPG), responsible for the removal of most N-alkyladducts in DNA, was purified to homogeneity as a recombinant nonfusion protein from Escherichia coli. Only 10-15% of the protein was present in the soluble form in E. coli cells. The N-terminal amino acid sequence of the purified protein which lacks 48 residues from the amino terminus of the wild type protein was identical to that predicted from the nucleotide sequence. The glycosylase hydrolyzes 3-methyladenine (m3A), 7-methylguanine(m7G), and 3-methylguanine (m3G) from DNA, and the Km and kcat values were 130 nM and 0.8 min-1 for m3A, and 860 nM and 0.2 min-1 for m7G, respectively, when methylated calf thymus DNA was used as the substrate. A comparison of kcat/Km values for different bases indicates that the enzyme was more efficient in excising both m3A and m3G than m7G from methylated DNA. The enzyme showed moderate binding affinities (KA) for both methylated (5.8 x 10(7) M-1) and nonmethylated DNAs (4.2 x 10(7) M-1). The mouse protein has an extinction coefficient E280nm1% of 10.5 and a pI of 9.3. The enzyme activity was optimal in the presence of 100 mM NaCl, with a broad pH optimum of 8.5-9.5. The enzymatic release of both m3A and m7G was stimulated 50-75% by 0.5 mM MgCl2 and 0.02 mM spermine but inhibited by higher concentrations of these agents. Product inhibition by 40-50% of the reaction occurred in the presence of 10 mM m3A or m7G. However, 1.0 mM m3A stimulated release of m7G. The enzyme was inhibited by 60% in the presence of 0.9 mg/mL DNA which, at the same time, protected it from thermal inactivation.

Plasma concentrations of immunoreactive inhibin and gonadotropins following removal of ovarian follicles in the domestic hen

In the domestic hen, the preovulatory follicles are arranged in a hierarchy. The largest (F1) follicle ovulates first, the second largest (F2) follicle ovulates approximately 26 h later, and so on. The nature of this regulation is not known. Inhibin has been implicated in the feedback regulation of FSH in mammals, and bioactive as well as immunoreactive inhibin has been demonstrated in chickens. The present experiments were conducted with two aims: 1) to determine the plasma level of immunoreactive inhibin in response to removal of various numbers of preovulatory follicles and 2) to assess the gonadotropin response to such follicle removal. In experiment 1, the F1 (n = 4), F1 + F2 (n = 5), F1 + F2 + F3 (n = 5), and F1 + F2 + F3 + F4 (n = 4) follicles were removed surgically. Sham-operated animals served as controls. Blood samples were taken at time 0 (prior to surgery) and at 6, 24, and 48 h after surgery. In experiment 2, animals were sham-operated (n = 5) or the F1-F4 (n = 4) or F1-F4 plus small yellow follicles (SYF; n = 5) were removed. Blood samples were removed at time 0 and at 3, 6, and 24 h and at daily intervals until Day 10 after surgery. In both experiments, plasma immunoreactive inhibin was significantly lowered (p < 0.001) and plasma FSH was acutely increased (p < 0.05) by follicle removal. Plasma LH was decreased at some time points after follicle removal.(ABSTRACT TRUNCATED AT 250 WORDS)

Characterization of a source and levels of plasma immunoreactive inhibin during the ovulatory cycle of the domestic hen

The domestic hen with its well-organized follicular hierarchy offers a unique model system for the study of the role of inhibin in follicular development. We have validated a homologous bovine RIA for use in the hen to measure plasma immunoreactive inhibin-like activity during the ovulatory cycle as well as during experimental conditions in which follicular development has been altered. Validation of the bovine RIA kit revealed that increasing amounts of hen plasma gave linear increases in the amount of immunoreactive inhibin detected. This assay system as well as a homologous chicken LH RIA were used to assess plasma concentrations of immunoreactive inhibin and LH, respectively, in experiments 1-3. In experiment 1, blood samples were collected from hens (n = 5) at 2-h intervals for 24 h starting at 1600 h after the lay of the last egg of the sequence through the following day. No significant peak in plasma immunoreactive inhibin level was detected during the ovulatory cycle, in spite of a significant preovulatory rise in plasma LH. The highest level of plasma immunoreactive inhibin was attained, however, 2 h prior to the preovulatory LH surge. In experiment 2, eCG (n = 6) or vehicle (n = 3) was administered to hens daily for 6 days. A blood sample was drawn immediately before injection each day as well as 24 h after the last day of treatment. Treatment with eCG significantly (p < 0.01) raised plasma immunoreactive inhibin-like levels, compared to vehicle-injected controls. In experiment 3, three to four of the largest follicles (F1-F4) were surgically removed, or sham surgery was performed.(ABSTRACT TRUNCATED AT 250 WORDS)

Prenatal cocaine use: impact on infants and mothers

Prenatal cocaine use does not allow a mother to provide an environment that promotes her infant's normal development. Pediatric nurses and other health care professionals need to support and assist the mother in the recovery process for the benefit of the child's health and development.

Adult respiratory distress syndrome. A complication of shock

ARDS is a complex type of respiratory failure that usually is a complication of a catastrophic critical illness, such as shock. Mortality is high, especially in patients with septic shock and multisystem failure. Mortality often is related to complications of refractory hypoxemia. Identifying patients at risk for developing ARDS and early recognition of ARDS are important so that treatment can be initiated to prevent the potentially lethal consequences of refractory hypoxemia. The nurse has an important role in collaborating with the physician and respiratory therapist to support the patient's oxygenation, ventilation, and tissue oxygen delivery system. The nurse is responsible for performing highly sophisticated assessment of clinical and hemodynamic parameters to evaluate the effectiveness of therapy. A key role of the nurse is anticipating, recognizing, and reporting to the physician complications of hypoxemia and complications of therapy that can lead to sepsis, airway trauma, or failure of other organ systems.

Idealism and realism in patient care during radiotherapy treatment

Previous research has demonstrated that typification of patients by health workers is inevitable even when these workers aspire to a concept of treating each patient as an individual. This study aimed to establish how six therapy radiographers, working in three different settings, typified their cancer patients and how this related to their concept of role and the environment in which they worked. The techniques used were ethnographic, non-directive interview techniques and naturalistic observation. There are interesting variations and similarities in how the individuals perceived their working role and environment and in their perception of patients. The typifications of patients by the therapy radiographers studied are related to and reflect the radiographers' concerns or stresses. They relate to the issues of information giving and receiving, control of the radiographer-patient relationship, how to cope with patient dependency and how this interacts with their own ideals and impression management. Some also reflect the problems experienced in working relationships, in particular balancing their own ideals with the reality of their working situation.

Pacemaker failure associated with therapeutic radiation

A 48-year-old white man with a multiprogrammable Intramedics 259-01 pacemaker was treated for inoperable lung cancer with a course of cobalt-60 radiotherapy (total 3,500 rad). Several weeks subsequent to his last radiation treatment, the patient presented to the emergency department with chest and abdominal pain, shortness of breath, hypotension, and tachycardia. A paced tachycardia was noted, and application of a magnet over the pacemaker completely inhibited its function, allowing a normal sinus rhythm to ensue and the patient's symptoms to be relieved. Pacemaker failure probably was a complication of radiotherapy.

Effect of doxycycline on pre-menstrual syndrome: a double-blind randomized clinical trial

Thirty patients with well-defined symptoms of pre-menstrual syndrome were randomly treated with the antibiotic doxycycline or placebo. The antibiotic-treated group showed a highly significant reduction of symptoms. Subsequent antibiotic treatment of the original placebo group similarly diminished the symptoms in this group. A 6-month follow-up demonstrated that the improvement in symptom scores was permanent and independent from the presence of the antibiotic. Luteal phase endometrial biopsies showed a high incidence of out-of-phase endometrium. An unexpectedly high percentage of endometrial biopsy cultures yielded positive findings for mycoplasma, Chlamydia trachomatis and anaerobic bacteria. There were no characteristic hormonal changes in this study group. An infectious aetiology, possibly a sub-clinical endometrial or ovarian infection, behind certain cases of pre-menstrual syndrome is postulated.

Adult physical activity behavior: a trend analysis

One of the health objectives for the nation is to have 60% of adults 18-64 years regularly active in vigorous physical activity by 1990. In this paper an effort is made to determine whether American society is making satisfactory progress toward this goal. Two independent databases are analyzed: time diaries collected from a national sample of American adults in 1981; and the Simmons Market Research Bureau, Inc., survey undertaken in 1984. Participation of adults 25-64 in moderate to vigorous activities that included racquet sports, swimming, hiking, bicycling, skiing, jogging, outdoor gardening, skating, etc. is compared between the two time periods. After adjusting for social desirability bias the results indicated there were a similar number of non-participants of the activities analyzed in 1981 and 1984. There was, however, an increase in the number of adults participating occasionally in vigorous activity, although, there did not appear to be any increase in the number who were regularly active, i.e. at least 3 days/week. Thus, while there are indications that adults 25-64 years are adopting more vigorous activity, less than 20% were regular enough in 1984 for improvements in cardiovascular functioning to occur. Unless there were dramatic increases in the activity status of adults 18-24 years of age which was not assessed in this study, the 1990 goal is unlikely to be met.

High failure rates in outpatient treatment of salpingitis with either tetracycline alone or penicillin/ampicillin combination

Eight hundred twenty-five ambulatory women with a clinical diagnosis of salpingitis were randomized to a 10-day course of either penicillin/ampicillin or tetracycline. Forty-four percent of women had gonococcal salpingitis and 56% nongonococcal salpingitis. Overall, both regimens cured equal proportions of women: At 30 days, 81% were cured by penicillin/ampicillin and 82% by tetracycline. However, the proportion of women with gonococcal salpingitis cured by 30 days was significantly greater than that of women with nongonococcal salpingitis. By 30 days, 14% of women with gonococcal salpingitis and 21% of women with nongonococcal salpingitis were not cured by either regimen. These data suggest that both regimens were only marginally acceptable for women with gonococcal salpingitis and that neither regimen was acceptable for nongonococcal salpingitis.

Rat liver acyl-coenzyme A:cholesterol acyltransferase: its regulation in vivo and some of its properties in vitro

To gain insight into the role of the enzyme acyl-coenzyme A:cholesterol acyltransferase (ACAT) in cellular cholesterol homeostasis, its regulation in rat liver was investigated both in vivo and in vitro. In vitro assay conditions were optimized and some properties of the microsomal enzyme in vitro was also studied. Arrhenius plots of microsomal ACAT activity showed discontinuities at about 28-29 degrees C and 16-17 degrees C. Detergents above their critical micelle concentrations and organic solvents both inhibited the enzyme. Addition of progesterone or SC 31769, a 7-keto-cholesterol analogue, to microsomes inhibited activity while addition of 25-hydroxycholesterol increased the rate of cholesterol esterification, suggesting that the enzyme is susceptible to both negative and positive modulation by steroids, steroid analogues, or their metabolic products. Increasing the rate of cholesterol biosynthesis had a variable effect on ACAT activity. It was higher at the circadian peak of sterol biosynthesis than at the nadir. Increasing sterol biosynthesis by intragastric administration of mevalonolactone resulted in increased activity. In contrast, increasing the rate of sterol biosynthesis by feeding cholestyramine or administration of Triton WR 1339 had little effect on ACAT. Increasing hepatic cholesterol content by feeding cholesterol, cholate, or an atherogenic diet, fasting or intragastric administration of mevalonolactone all resulted in increased ACAT activity. ACAT activity showed a positive correlation with changes in microsomal free and esterified cholesterol contents. The response of ACAT to changes in hepatic cholesterol concentration in vivo and its response to changes in the rate of cholesterol synthesis support the hypothesis that this enzyme plays an important role in maintenance of hepatic cholesterol homeostasis.