Ontogenic development of brown adipose tissue in Angus and Brahman fetal calves.

Brahman calves experience greater neonatal mortality than Angus calves if cold-stressed. To establish a developmental basis for this, three fetuses of each breed type were taken at 96, 48, 24, 14, and 6 d before expected parturition, and at parturition. Overall fetal BW tended (P = 0.08) to be greater for Angus than for Brahman fetuses. There was no difference between breed types in total brown adipose tissue (BAT) mass or grams of BAT/kg BW. Brown adipocyte density decreased 56%, whereas lipogenesis from acetate and glucose in vitro decreased 97% during the last 96 d of gestation in both breed types. Glycerolipid synthesis from palmitate declined by 85% during the last trimester but still contributed 98% to total lipid synthesis at birth. The fetal age x breed interaction was significant for lipogenesis from glucose (P = 0.05) and palmitate (P = 0.005); rates were higher at 96 d before birth in Brahman BAT but declined to similar rates by birth. Uncoupling protein-1 (UCP1) mRNA tripled during gestation in both breed types (P = 0.002), whereas mitochondrial cross-sectional area did not change (P = 0.14) during gestation. Neither the breed nor the age x breed effect was significant (P > or = 0.24) for UCP1 mRNA concentration or mitochondrial cross-sectional area. In both breed types, a marked decrease in BAT UCP1 mRNA between 24 and 14 d prepartum was associated with a similar reduction in lipogenesis from palmitate and a noticeable change in BAT mitochondrial morphology, as the mitochondria became more elongated and the cristae became more elaborate. Uncoupling protein-1 mRNA initially was elevated in Angus tailhead s.c. adipose tissue, but was barely detectable by birth, and tended to be greater overall (P = 0.09) in Angus than in Brahman BAT. If uncoupling protein activity in s.c. adipose tissue persists after birth, then s.c. adipose tissue may contribute more to thermogenesis in Angus newborn calves than in Brahman calves. In contrast, we did not observe differences in ontogenic development of perirenal BAT that could explain the documented differences in thermogenic capacity between Angus and Brahman newborn calves.

Pharmacokinetic and pharmacodynamic monitoring of the elderly in critical care.

The cases presented illustrate the clinical application of several of the common pharmacokinetic and pharmacodynamic changes in the elderly. The number of drugs that must be used with caution in the aging person is potentially quite large. In addition, there are numerous other diseases that can result in additional changes in drug absorption, distribution, metabolism, excretion, and target-organ effect. These conditions are particularly prevalent in the elderly patient in the critical care setting, and include the systemic inflammatory response syndrome, sepsis, acute renal failure, diabetic ketoacidosis, and the postoperative state. It must be emphasized, however, that the elderly are not a homogeneous group. The rate of decline of many physiologic functions varies widely. Chronic diseases and lifestyle alterations are additional variables that affect the function of many body systems. Furthermore, it is likely that the different pharmacokinetic and pharmacodynamic parameters discussed in this article do not all change to the same degree in a given individual. Pharmacologic therapy, therefore, always will be quite empiric in elderly patients. There is no substitute for meticulous monitoring of the patient using every available modality. This is particularly crucial in the critical care setting, where drugs can be lifesaving and life threatening at the same time.

Literacy and self-reported educational levels in relation to Mini-mental State Examination scores.

BACKGROUND AND OBJECTIVES: Because of its brevity and ease of use, the Mini-mental State Examination (MMSE) is commonly used to screen and follow patients with cognitive impairment. This pilot study attempted to determine the relationships between literacy, age, and self-reported educational level and the total MMSE score. METHODS: Cross-sectional analysis of all patients was followed by a family practice group at five local nursing homes. The associations between the patients' MMSE scores; literacy, as measured by the Rapid Estimate of Adult Literacy in Medicine (REALM); self-reported educational level; and age were determined using Pearson's correlation coefficient and stepwise multivariate linear regression. RESULTS: A total of 105 patients completed the study. Linear regression analysis showed that MMSE scores were significantly predicted by REALM score (P < .001) and the patient's age (P < .02). However, after accounting for REALM score and age, the self-reported educational level was not related to the MMSE score (P < .8). A significant relationship was seen between the REALM score and the subjects' self-reported educational levels (r = .44, P < .001) but not the subjects' ages (r = -.17, P < 0.09). A significant linear correlation was found between the MMSE and REALM scores (r = .71, P < .0001) and a significant inverse correlation was seen between MMSE scores and the patients' ages (r = -.28, P < .004). The correlation coefficient between the patients' MMSE scores and the self-reported educational levels was .33 (P < .0007). CONCLUSIONS: Practitioners who rely on the MMSE should be aware that patients may score in the demented range because they cannot read well enough to accurately complete the test. Literacy testing with REALM or other instruments may help identify such patients.

On the relationships among headache symptoms.

Headache classification has evolved through clinical experience because there are no objective findings which define causation or headache type. The resulting groupings are inconsistently defined, and may not be optimal for the study or treatment of headache patients. To determine whether the same headache types would have resulted if today's sophisticated statistical methods had been applied to standard data collected on unselected patients, 21 symptoms collected from 726 patients with acute headaches were analyzed. Five "natural' groupings or syndromes of symptoms were found in the data. Three were similar to traditional groupings: tension, migraine and cluster. Approximately one fourth of the patients had both tension and migraine symptoms, which suggests that the division of headaches into "tension' vs "migraine' has a large overlap. An "OCULAR' and a "URI' syndrome were also detected. Contrary to expectations, vascular headaches were not usually unilateral and patients with cluster headache symptoms were not usually males. The discrepancy between these findings and current perceptions may have been caused by differences in the populations or from biased patient selection in previous studies.

Reproducibility of clinical data and decisions in the management of upper respiratory illnesses: a comparison of physicians and non-physician providers.

The ability of non-physician providers to collect the data required by an algorithm for upper respiratory illness management, and the appropriateness of resulting key management decisions, were studied by comparing non-physician data and management decisions on 426 patients with those of internists. The internists, blinded to Amosists' findings and plans, evaluated the same patients and indicated management without using the algorithm (AM-MD) study). To control for variability of internists' data collecting and illness management, 171 additional patients were evaluated and managed consecutively by two internists, each also kept unaware of the other's findings and plans (MD-MD study). Overall AM-MD agreement on history and physical findings (90 per cent and 81 per cent) and on the need for tests (84 per cent) and treatment (87 per cent) was as high as MD-MD aggrement (91 per cent, 80 per cent, 88 per cent, and 75 per cent, respectively). In both studies, there was significantly more agreement on history data than on physical findings, evaluation, and therapy.

Transient ST elevation associated with tension pneumothorax.

In a 52-year-old man, a spontaneous right tension pneumothorax was associated with transient bradycardia, hypotension and electrocardiogram (ECG) changes consisting of precordial ST elevation suggestive of acute myocardial injury. Immediately after chest tube placement, the ECG reverted to near normal. Serial cardiac enzymes and isoenzymes showed no evidence of myocardial infarction. To our knowledge, this is the first reported case of this association. The ECG changes may be related to the hypotensive state induced by the tension pneumothorax with resulting decreased coronary artery blood flow and myocardial ischemia that resolved without infarction.

Algorithm-directed triage in an emergency department.

At Brooke Army Medical Center the Emergency Services Section has developed an algorith,-directed triage system to be used by "screeners" who may be basic medical corpsmen but sometimes have had no previous medical experience. After 25 hours of classroom and 120 hours of on-the-job training, the screeners use the algorithms to triage patients into one of three treatment areas in the emergency section or to clinics outside the emergency section during the day and evening. The screeners may consult with a triage physician if the algorithm-directed disposition appears inappropriate, Triage dispositions of 78,822 patient visits during the calendar year 1975 are presented.