Metabolic adaptations to heat stress in growing cattle.

To differentiate between the effects of heat stress (HS) and decreased dry matter intake (DMI) on physiological and metabolic variables in growing beef cattle, we conducted an experiment in which a thermoneutral (TN) control group (n=6) was pair fed (PF) to match nutrient intake with heat-stressed Holstein bull calves (n=6). Bulls (4 to 5 mo old, 135 kg body weight [BW]) housed in climate-controlled chambers were subjected to 2 experimental periods (P): (1) TN (18 degrees C to 20 degrees C) and ad libitum intake for 9 d, and (2) HS (cyclical daily temperatures ranging from 29.4 degrees C to 40.0 degrees C) and ad libitum intake or PF (in TN conditions) for 9 d. During each period, blood was collected daily and all calves were subjected to an intravenous insulin tolerance test (ITT) on day 7 and a glucose tolerance test (GTT) on day 8. Heat stress reduced (12%) DMI and by design, PF calves had similar nutrient intake reductions. During P1, BW gain was similar between environments and averaged 1.25 kg/d, and both HS and PF reduced (P<0.01) average daily gain (-0.09 kg/d) during P2. Compared to PF, HS decreased (P<0.05) basal circulating glucose concentrations (7%) and tended (P<0.07) to increase (30%) plasma insulin concentrations, but neither HS nor PF altered plasma nonesterified fatty acid concentrations. Although there were no treatment differences in P2, both HS and PF increased (P<0.05) plasma urea nitrogen concentrations (75%) compared with P1. In contrast to P1, both HS and PF had increased (16%) glucose disposal, but compared with PF, HS calves had a greater (67%; P<0.05) insulin response to the GTT. Neither period nor environment acutely affected insulin action, but during P2, calves in both environments tended (P=0.11) to have a blunted overall glucose response to the ITT. Independent of reduced nutrient intake, HS alters post-absorptive carbohydrate (basal and stimulated) metabolism, characterized primarily by increased basal insulin concentrations and insulin response to a GTT. However, HS-induced reduction in feed intake appears to fully explain decreased average daily gain in Holstein bull calves.

The importance of communication in secondary fragility fracture treatment and prevention.

INTRODUCTION: We report on a Canadian longitudinal qualitative case study of midlife women with fragility fractures, their treating orthopaedic surgeons and family physicians. METHODS: Women and their treating physicians were followed for an average of one year post fracture to investigate the health outcomes and what, if any, follow-up occurred aimed at secondary fracture prevention. The final dataset includes 223 interviews gathered from women aged 40 to 65 with fragility fractures, orthopaedic surgeons and family physicians. RESULTS: The circle of care for those with fragility fractures is disrupted at vital communication junctures: (1) the inconsistent flow of information between acute care institutions and family physicians; (2) unidirectional and inconsistent communication from orthopaedic surgeons to family physicians; and (3) competing demands of the cast clinic environment and patient expectations. It is not the lack of will that is undermining the consistent and detailed communication among patients, physicians and institutions. It is the episodic nature of fracture care that makes communication among involved parties difficult, if not impossible. CONCLUSIONS: Communication about events, acuity and clear expectations around roles and follow-up is urgently needed to improve communication throughout the circle of care to support secondary fracture prevention. Fractures from a standing height or similar trauma in women aged 40 to 65 should be treated as suspicious fractures and followed-up to investigate the underlying bone condition. This article reports on challenges and barriers to clear communication among women, their orthopaedic surgeons and family physicians that is necessary for follow-up and prevention of future fractures.

Management of epilepsy in women.

There are many aspects to the management of epilepsy in women related to their role in reproduction. Some of these need to be considered in adolescents, some are related to pregnancy, concerning both the mother and her infant, and others with the menstrual cycle and the menopause. This review considers contraception, fertility, teratogenicity, and the use of folic acid. It also discusses the special investigations in pregnancy, hyperemesis, the effect of pregnancy on the control of epilepsy, the effect of seizures on the fetus, a first fit in pregnancy, pseudoseizures, seizures during delivery, vitamin K, breast feeding, postpartum maternal epilepsy, hereditary risks, counselling, catamenial epilepsy, the menopause, and bone density.

An unusual cause of falls in an elderly patient.

Falls are common in the elderly, often causing considerable morbidity and mortality. Prevention is therefore important and is based on determining the cause. We present an elderly patient who had multiple falls during the day due to recurrent daytime sleep episodes, an entity we believe has not previously been reported.

Octreotide inhibition of flushing and colonic motor dysfunction in carcinoid syndrome.

OBJECTIVES: Previous studies showed increased plasma motilin and substance P concentrations and accelerated motor function in the small bowel and colon in patients with carcinoid diarrhea. Octreotide is beneficial in patients with carcinoid syndrome. Our hypothesis was that octreotide inhibits accelerated motility and gut neuropeptides in carcinoid syndrome. METHODS: In 12 patients with metastatic carcinoid syndrome, we investigated the effect of octreotide 50 microg s.c. t.i.d (n = 6) or placebo (n = 6) on postprandial symptoms, GI transit, colonic motility, and circulating levels of selected circulating peptides and amines. RESULTS: Octreotide reduced postprandial flushing (p = 0.03) but not pain. Octreotide significantly retarded overall colonic transit and proximal colonic emptying (p < 0.05); it tended to prolong small bowel transit time (p = 0.13) and to reduce postprandial colonic tone (p = 0.08) compared with placebo. Octreotide also reduced circulating levels of peptide YY, neurotensin, vasoactive intestinal polypeptide, and substance P but had no effect on plasma motilin, neuropeptide Y, calcitonin gene-related peptide, or histamine after meal ingestion. CONCLUSION: Octreotide ameliorates gut motor dysfunctions that characterize carcinoid diarrhea; the potential role of specific antagonism of serotonin, substance P, and vasoactive intestinal polypeptide alone or in combination with agents that inhibit their release in carcinoid diarrhea deserves further study.

A pilot study of motility and tone of the left colon in patients with diarrhea due to functional disorders and dysautonomia.

OBJECTIVE: Our aim was to identify qualitative or quantitative colonic motor patterns induced postprandially in a pilot study of patients with diarrhea due to functional disease or dysautonomia to identify objective endpoints for future studies. METHODS: In patients with functional diarrhea (n = 5) or dysautonomia (n = 4) in whom GI transit was documented by scintigraphy, we studied colonic motility by combined manometry and barostat measurements for 1 h fasting and 2 h postprandially (1000-kcal meal). Data were compared with those of healthy control subjects. RESULTS: There were no differences in compliance, overall phasic motility of the left colon, fasting tone, or maximal change in postprandial tone in the diarrhea group as compared with the control group. The diarrhea group showed more high amplitude propagated contractions 4.4 +/- 3.6 (SD)/2 h, p < 0.05) compared with the control group (0.7 +/- 1.4/2 h); the mean postprandial tonic response (12 +/- 14%, p < 0.05) and its duration were reduced in the diarrhea group compared with the control group (27 +/- 17%). Two dysautonomic patients showed a paradoxical relaxation of the colon postprandially. CONCLUSION: Reduced duration of increased colonic tone postprandially and increased number of high amplitude propagated contractions seem to be useful objective endpoints for future studies.

Effect of cholecystokinin octapeptide and atropine on human colonic motility, tone, and transit.

The role of cholecystokinin (CCK) in postprandial control of colonic motility is controversial. To test the hypothesis that CCK stimulates colonic tone, motility, and transit we measured these colonic functions in 16 healthy subjects using intraluminal manometry, barostatic balloon measurements, and radioscintigraphy. This was a randomized-order, double-blind, sequential study design in each subject of saline and either atropine (0.01 mg/kg stat and 0.01 mg/kg/hr by infusion) or CCK-octapeptide (OP, 30 ng/kg stat and 60 ng/kg/hr by infusion). Atropine was used as control to demonstrate responsiveness of selected parameters of colonic motility. Atropine significantly reduced whole colon (change from fasting = 52 +/- 11%) and left colon (change from fasting 61 +/- 8%) phasic pressure activity and transverse colon tone (change from fasting 159 +/- 40%); CCK-OP had no significant effects on phasic contractility, tone or transit. Thus, a CCK-OP infusion that maximally stimulates pancreatic exocrine secretion and gallbladder contraction has no effect on motor function or transit in prepared colon of healthy subjects.

Motility and tone of the left colon in constipation: a role in clinical practice?

OBJECTIVES: Colonic motor mechanisms deranged in constipation are not understood completely. Our aim was to measure left colonic motility and tone, during fasting and postprandially in patients with chronic constipation. METHODS: During 1 h fasting and 2 h postprandially, we measured pressures (multilumen manometry) and tone (barostat) in the left colon of 15 healthy controls and 40 patients with chronic constipation associated with slow (n = 15) or normal colonic transit (n = 12) or outlet obstruction (n = 13). RESULTS: Fasting tone was similar in all groups, and all demonstrated a significant increase in motor activity to food. There was lower postprandial tone (p < 0.05) in the slow transit and outlet obstruction groups. There were no differences in the timing of the tonic response or the number or amplitude of high-pressure propagated contractions. The slow transit group had lower postprandial phasic responses in the rectosigmoid (p < 0.05) and descending (p < 0.1) colon; the outlet obstruction group had lesser descending (p < 0.05) and rectosigmoid (p < 0.1) colon phasic motility. CONCLUSIONS: Colonic intraluminal measurements alone do not discriminate subgroups of chronic constipation more accurately than transit and pelvic floor tests, and currently have a limited role in clinical practice. However, manometry and tone measurements may be helpful in confirming a diagnosis of slow transit constipation (colonic inertia) in patients considered candidates for surgical treatment.

Colonic motility in health and disease.

Being the final pathway for chyme and digestive residues, the colorectum influences bowel function critically. The most important and relevant symptoms of colonic dysfunction are diarrhea, constipation, urgency, and pain. Despite the effects of many investigators, over several decades, the motor physiology of the human colon is still relatively obscure. Most is known about patterns of colonic transit. In practice, measurements of transit are the best characterized and most widely available tests of colonic motor function. Colonic hypersensitivity, implying an abnormality of afferent signaling, is assuming greater importance in the pathophysiology of conditions as common as IBS and inflammatory bowel disease.

Hospital reimbursement for pediatric trauma care.

PURPOSE: Despite the proven efficacy of pediatric trauma centers, their continued development is threatened by the perception that their cost exceeds the reimbursement for their services. The authors reviewed actual reimbursement for a group of pediatric trauma patients and compared with that for a group of appendectomy patients chosen to reflect the authors' surgical population at large. METHODS: The records of 209 consecutively treated trauma patients and 37 age-matched appendectomy patients treated in 1992 and 1993 were reviewed. Trauma patients were divided into two groups: moderate injury (ISS < or = 9; n = 134) and serious injury (ISS > or = 10; n = 75). RESULTS: Hospital bills for the appendectomy patients were reimbursed at 72% of charges and 112% of costs. Payment was received at a mean of 36 days (range, 9 to 62 days) after discharge. Reimbursement for moderately injured patients was 104% of charges and 137% of costs and was received at a mean of 81 days (range, 3 to 270 days) after discharge. Six months postdischarge, reimbursement for seriously injured patients was 63% of charges and 86% of costs. Reimbursement was slow for some children who sustained severe injury, but as legal actions brought by patient's families were completed, open accounts were settled, and revenue in both groups totaled 76% of charges and 103% of costs 18 months postdischarge. CONCLUSION: Hospital reimbursement for care at a level I pediatric trauma center exceeds 75% of charges and 100% of costs, no different from the overall rate for the general hospital surgical population. Analysis of reimbursement rates for trauma patients may be time-dependent.

The rumination syndrome: clinical features rather than manometric diagnosis.

BACKGROUND/AIMS: Rumination is infrequent in adults of normal mental capacity. Upper gastrointestinal manometry reportedly confirms the diagnosis. Clinical characteristics, treatment(s), and outcomes of these patients are unclear. METHODS: We assessed 38 adults and adolescents with rumination between 1987 and 1994. Esophagogastroduodenal manometric recordings (n = 36; 3-hour fasting and 2-hour postprandially) were reviewed; follow-up information was obtained from mailed questionnaires. RESULTS: Patients saw a mean of five physicians and had symptoms for a mean of 2.75 years before diagnosis. Features included daily, effortless regurgitation of undigested food starting within minutes of meals. Weight loss was substantial (mean, 29 lb) in 42% of patients. Seventeen percent of female patients had a history of bulimia. Manometry confirmed the clinical diagnosis in 33% but was otherwise normal in all. Of 16 patients who responded to our questionnaires of 29 with > 6 months of follow-up (average, 35 months), 12 reported subjective improvement. In 14, the behavior persists. CONCLUSIONS: The rumination syndrome is underdiagnosed. With typical clinical features, gastroduodenal manometry seems unnecessary to confirm the diagnosis. Diagnosis and reassurance are important in management to avoid unnecessary tests and treatments.

Cortical myoclonus in Huntington's disease.

We describe three patients with Huntington's disease, from two families, in whom myoclonus was the predominant clinical feature. The diagnosis was confirmed at autopsy in two cases and by DNA analysis in all three. These patients all presented before the age of 30 years and were the offspring of affected fathers. Neurophysiological studies documented generalised and multifocal action myoclonus of cortical origin that was strikingly stimulus sensitive, without enlargement of the cortical somatosensory evoked potential. The myoclonus improved with piracetam therapy in one patient and a combination of sodium valproate and clonazepam in the other two. Cortical reflex myoclonus is a rare but disabling component of the complex movement disorder of Huntington's disease, which may lead to substantial diagnostic difficulties.

How does cerebrovascular disease cause dementia?

There are several factors that might be important in the development of dementia due to cerebrovascular disease. These include the volume of infarcted brain, the bilaterality and symmetry of lesions, the strategic location of small lesions, the number of lesions, the extent and density of white matter lesions and the coexistence of other pathologies, particularly Alzheimer's disease. No one factor is solely related to dementia and in most patients several of these factors combine to exceed the critical threshold for normal cognition. It is the extent of the disease which determines the development of dementia, rather than its etiology. Conversely, the possibility of treatment depends more on the etiology of the vascular disease than on the extent.