The herpesvirus protease: mechanistic studies and discovery of inhibitors of the human cytomegalovirus protease

This paper is a review of the literature on the possible association between osteoporosis and oral bone loss, with an emphasis on radiological studies. Such an association was first suggested in 1960. Subsequent histomorphometric and microradiographic studies showed that after the age of 50 there was a marked increase in the cortical porosity of the mandible, with this increase being greater in the alveolar bone than the mandibular body; and that with this increase in porosity, there was a concomitant decrease in bone mass, which appeared to be more pronounced in females than in males, with the loss in bone mineral content estimated to be 1.5% per year in females and 0.9% in males. These studies also demonstrated a considerable amount of variation in the amounts of cortical and trabecular bone within and among individuals. Subsequent clinical studies reported associations between the bone densities of jaws and (1) metacarpals, (2) forearm bones, (3) vertebrae and (4) femurs. These studies indicated that women had lower mandibular bone mineral content (BMC) than men and that age-related loss of bone was more pronounced in women after the age of 50 years than in men of the same age, as was the case for the rest of the body. It was suggested that systemic factors responsible for osteoporotic bone loss may combine with local factors (periodontal diseases) to increase rates of periodontal alveolar bone loss. Although not all studies found associations between osteoporosis and oral bone loss, the conclusion of this review is that such an association exists; yet additional longitudinal investigations are needed to confirm this, and before the implications of this association could be fully utilized in clinical dentistry, inexpensive methods must be developed for sensitive and specific measures of oral bone loss.     

p+-n-p+ BARITT-diode design

p+-n-p+ BARITT diodes have been designed to give maximum output power at X band frequencies. Computed output power against frequency shows good agreement with measured powers. The dominant effect of the maximum n region electric field on output power is demonstrated.     

Cultures in conflict: a challenge to faculty of academic health centers

BACKGROUND: Most patients receiving accelerated fractionation radiotherapy or chemoradiotherapy for head and neck cancer experience severe mucositis. This can lead to decreased oral intake, resulting in dehydration, severe malnutrition, hospitalization, and/or interruption of radiotherapy. OBJECTIVE: To evaluate the effect of prophylactic gastrostomy tubes (PGTs) on the rates of weight loss, unplanned interruptions, and hospitalization during high-intensity head and neck radiotherapy. METHODS: A retrospective review was performed on 88 patients treated for locally advanced head and neck cancer with accelerated twice-a-day radiation (n = 59) or concurrent chemoradiotherapy (n = 29). Prophylactic gastrostomy tubes were placed in 36 (41%) of patients in anticipation of increased acute toxic effects from treatment. The remaining patients without PGTs served as a control group. RESULTS: Patients without PGTs lost an average 3.1 kg compared with 7.0 kg in the control group (P<.001). There were significantly fewer hospitalizations for nutritional or dehydration issues in those with PGTs than in the control group (13% vs 34%; P = .04, chi2 test). Among those with good performance status, no patient with a PGT required a treatment interruption, compared with 18% of patients without a PGT (P = .08). Sixteen patients (31%) in the control group underwent therapeutic gastrostomy tube placement during or after radiation therapy. CONCLUSIONS: The use of PGTs significantly reduces weight loss and the rate of hospitalization for dehydration and complications of mucositis. Treatment interruptions may also be avoided by the use of PGTs in patients with good performance status. We encourage patients scheduled for intensive radiation therapy to receive a PGT.     

Development of use and cost measures in a nursing intervention for family caregivers and frail elderly patients

The purpose of this pilot study was to refine and evaluate methods of measuring costs of an innovative home-health nursing intervention designed to support frail, older persons and their family caregivers. We evaluated a multifaceted strategy to collect a detailed utilization profile from 22 caregiver/care receiver dyads for hospital, ambulatory, home health, nursing home, and community services. The strategy was feasible for most participants, maximized accuracy of cost data, and minimized research burden on study participants. Lower overall costs were found in the intervention group, but the difference was not significant. Approaches to the measurement of costs in this study can serve as models for evaluating other innovations in nursing, home care, and long-term care.     

GLP-1 tablet in type 2 diabetes in fasting and postprandial conditions

OBJECTIVE: To examine the absorption of glucagon-like peptide (GLP)-1(7-36) amide from the buccal mucosa of type 2 diabetic patients. Previously, the effects of the peptide have been studied following intravenous and subcutaneous injection. Now, a mucoadhesive, biodegradable buccal GLP-1 tablet (9 mm) containing 119 nmol has been developed as a possible alternative to injection. RESEARCH DESIGN AND METHODS: A total of 10 type 2 diabetic patients received a single tablet under fasting conditions and before a standard meal in this randomized placebo-controlled study. RESULTS: The mean peak GLP-1 concentration was 125.1 pmol/l and occurred 30 min after application. The mean placebo-adjusted area under the curve was 5,334 min pmol/l, consistent with a relative bioavailability of 6% vs. intravenous injection and 42% vs. subcutaneous injection. The half-life of total peptide activity after buccal administration was 17 min. The placebo-adjusted glucose concentrations decreased by 1.4 mmol/l in fasting experiments and by 4.2 mmol/l after a standard mixed meal. In the fasting state at 30 min, plasma insulin increased by 185% and glucagon decreased by 20%, consistent with the increase in plasma GLP-1 concentrations. The peptide exerted a significant insulinotropic effect during meals (calculated as an insulinogenic index, 0-120 min; 84.1 vs. 45.7 in placebo experiments). CONCLUSIONS: Potentially therapeutic plasma levels of GLP-1 were achieved after administration of a single buccal tablet in type 2 diabetic patients. The peptide had a marked glucose-lowering effect during the first 2 h. This new GLP-1 tablet may become a feasible alternative treatment for type 2 diabetic patients, although a more prolonged pharmacokinetic profile is required.     

Enteral tube feeding in a patient with traumatic brain injury

Tube feeding is frequently needed for patients with severe traumatic brain injury. When the patient is on the rehabilitation unit, bolus type feeding by gastrostomy tube is more easily accomplished than continuous type feeding by jejunostomy tube (J-tube). In the case presented here, the patient received less calories via J-tube feeds while he was on the rehabilitation unit than when he was in the intensive care unit or the neurosurgical unit. This has implications for the trauma team, which initially decides the type of nutritional support.     

The management of metformin overdose

Only two cases of deliberate self-poisoning with metformin have been described in the literature. We report the management of three cases, all of which presented with severe lactic acidosis. Two cases had a fatal outcome. The options for treatment and previous cases reported in the literature are reviewed. Recommendations for the management of metformin overdose include early recognition, intensive support of the cardiovascular system, the correction of metabolic acidosis and the maintenance of body temperature. The use of venovenous haemofiltration against a non-lactate containing fluid may improve outcome when sodium bicarbonate alone fails to reverse severe systemic acidosis.     

Fluid flow through a solid-liquid dendritic interface

Fluid flow through a dendritic solid-liquid interfacial zone, during solidification, has been observed in a series of Sn-Pb alloys. It was found that liquid penetrates only a short distance into the zone, relative to the total thickness of the zone. The amount of solid present at the point of maximum penetration varies from 12 to 22 pct, and depends on the alloy concentration. Flow due to volume shrinkage, thermal convection, or solute convection well inside the zone, was not detected. Fluid flow through a wire mesh model of a thin section of the solid-liquid dendritic zone was examined. The results are not in agreement with that predicted for flow through a porous barrier, which had been found applicable to interdendritic fluid flow. Formerly Graduate Student, University of British Columbia, Vancouver, British Columbia, Canada