Evaluation of cetylpyridinium chloride for infection control in storage solution

Storage solution is used in in vitro experimental studies to prevent dehydration of teeth collected immediately after extraction and to prevent bacterial and fungal growth in the storage media. The chemical nature of the storing agent may affect the tooth structure and material properties at the tested interface. The aim of this study was to evaluate the use of 0.1% cetylpyridinium chloride (CPC) as a new storage solution and to assess the possible effect of 0.1% thymol on microleakage and bond strength. Forty extracted human teeth were collected from 10 different dental clinics. Immediately after extraction, the teeth were randomly divided and immersed in four different storage solutions. Two test solutions of 0.1% CPC (group C) and 0.1% thymol (group T) were compared with phosphate-buffered saline (Group S - positive control) and to 3% H2O2 (group H - negative control). Bond strength test and dye penetration evaluation were then carried out. The findings suggest that the use of 0.1% CPC as storage solution does not affect bond strength to enamel. However, it may increase dye penetration at the cervical margin. The effect of 0.1% thymol on shear bond strength and dye penetration is similar to the effect of phosphate-buffered saline.

Relationship of asthma to irritant gas exposures in pulp and paper mills

The potential of chronic or acute irritant gas exposures to cause asthma or a variant condition, reactive airways dysfunction syndrome (RADS) was investigated by observing asthma incidence in a large working population, using person-years at risk (P-YR) to compute relative rates (RR). Health data came from employee examinations at 62 pulp and paper plants. The 39122 workers who denied asthma beginning before the observation period included: 19326 denying irritant exposures, with no gassing exposures; 19349 with self-reported irritant exposures, and no gassing; and 447 with documented gassings. Asthma was defined as self-reported asthma beginning after the start of observation. P-YR accrued from September 29, 1986, for the nonexposed and exposed workers, and from date of first gassing for gassed workers, and ended with disease onset in any who developed asthma. RR of asthma with 95% confidence intervals (CI95) were calculated for the exposed and gassed groups, relative to the nonexposed. Exposed (nongassed) workers had an elevated asthma rate, RR=1.48, CI95=1.17-1.86, after adjustment for effects of gender and number of examinations. The rate in gassed workers was not significantly elevated: RR=1.95, CI95=0.75-5.08. Of the five asthma cases occurring after gassings, none conformed to diagnostic criteria for RADS. Chronic exposures were associated with increased rate of asthma onset, which must be interpreted with caution because self-reported data defined both exposure category and disease. Documented gassings were not associated with significantly increased rate, and none of 447 gassed persons developed RADS.

Formulation, development and characterization of sustained release varnishes containing amine and stannous fluorides

This study describes properties of potential sustained release varnishes (SRV) containing amine fluoride or amine fluoride with stannous fluoride. The release kinetics, antibacterial properties and antiadhesion properties of two potential varnishes were tested. The varnish of ethylcellulose matrix was found to release fluoride for 4 h in vitro, while the formulation based on hydroxypropylmethylcellulose acetate succinate had a rapid release rate. Hydroxyapatite tablets coated with ethylcellulose-based SRV increased adhesion of Streptococcus mutans, while tablets coated with hydroxypropylmethylcellulose acetate succinate-based SRV decreased bacterial adhesion. Both types of SRV demonstrated a strong antibacterial effect on bacteria in biofilm.

A computer-assisted anatomical study of the nasofrontal region

OBJECTIVES/HYPOTHESIS

Objectives were as follows: 1) to define the variations of the uncinate process' superior attachment, 2) to study the diameter of the frontal sinus ostium, 3) to study the prevalence of the agger nasi cells, and 4) to evaluate the side-to-side variability of these structures.

STUDY DESIGN

A retrospective clinical study at a tertiary care center.

METHODS

One hundred forty-four consecutive computed tomography scans were studied with image-guided surgery software (InstaTrak, Visualization Technology, Inc., Wilmington, MA) that provides continuous coronal, sagittal, and axial sections. We reported the superior attachment sites of the uncinate process, the diameter of the frontal sinus ostium, and prevalence of the agger nasi cells.

RESULTS

The uncinate process' main superior attachment into the surrounding structures was found to have the following distribution: 52% to the lamina papyracea, 18.5% to the posteromedial wall of the agger nasi cell, 17.5% to the lamina papyracea and the junction of the middle turbinate with the cribriform plate, 7% to the junction of the middle turbinate with the cribriform plate, 3.6% to the ethmoid roof, and 1.4% to the middle turbinate. The frontal ostium anterior-posterior diameter (mean +/- SD) was 7.22 +/- 2.78 mm and its transverse diameter (mean +/- SD) was 8.92 +/- 2.95 mm. Agger nasi cells were found in 78% of the scans.

CONCLUSIONS

The frontal sinus opens into the middle meatus medial to the uncinate process in 88% of the patients and lateral to the uncinate process in 12% of the patients. The naturally wide dimensions of the frontal ostium help to explain why postoperative patency can be achieved merely by exposing the ostium without the need to enlarge it. The frontal ostium dimensions in one side may differ considerably from the contralateral side. An agger nasi cell or a terminal recess, or both, are found in most cases. Image-guided surgery software is a helpful new tool for anatomical studies and for preoperative evaluation.

Antibacterial effect of parabens against planktonic and biofilm Streptococcus sobrinus

Tooth decay is an infectious disease caused by bacteria immobilized on the tooth surfaces. Eradication of these bacteria, for example Streptococcus sobrinus (S. sobrinus), from the oral cavity is essential in the prevention and treatment of tooth decay. We have tested the antimicrobial effect of several paraben derivatives such as methyl (MP), ethyl (EP), propyl (PP) and butyl (BP) against immobilized and planktonic S. sobrinus. The antibacterial effect was as follows: MP>EP>PP=BP on immobilized bacteria and MP>EP=PP>BP on planktonic bacteria. An antibacterial synergistic effect was found between several combinations of parabens on immobilized and planktonic S. sobrinus. Our results indicate that parabens are potential antibacterial agents against immobilized or planktonic bacteria found in the oral cavity.

The occurrence of sleep-disordered breathing among patients with head and neck cancer

OBJECTIVE

To identify the incidence of obstructive sleep apnea (OSA) in patients treated for head and neck cancer. Obstructive sleep apnea is a relatively common and highly morbid condition that affects 9.1% of male and 4% of female middle-aged adults.1 Patients who have been successfully treated for head and neck cancer may often have a partially obstructed upper airway which is functional during the day, but collapses during sleep.

STUDY DESIGN/METHODS

Twenty-four patients successfully treated for tumors of the tongue-base, pharynx, or supraglottic larynx were enrolled. Through OSA-related questionnaires, physical examination, and polysomnography, the incidence of OSA in this patient population was determined and compared with that of the general population.

RESULTS

The incidence of OSA (91.7%) in this head and neck cancer patient population was found to be significantly (P =.001) higher than that of the general population. (In a random sampling of middle-aged adult males between the ages of 30 and 60 years old with a respiratory disturbance index (RDI) >15, the prevalence was previously reported to be 9.1%.1) Sixteen of 24 patients (72.7%) had clinically defined symptoms of sleep apnea. Ten of 24 patients (41.7%) received radiation therapy; all had an RDI >15. Eleven of the 14 patients (78.5%) who did not receive radiation therapy also had an RDI >15. Eight patients (33.3%) continue to regularly use continuous positive airway pressure with significant improvement in symptoms.

CONCLUSIONS

Identification and treatment of OSA may be an important factor in improving quality of life for patients with head and neck cancer.

Event-related potentials in schizophrenia during tonal and phonetic oddball tasks: relations to diagnostic subtype, symptom features and verbal memory

BACKGROUND

This study compares event-related potentials for paranoid patients (n = 13) versus matched undifferentiated patients and unmedicated patients (n = 14) versus matched healthy adults.

METHODS

Event-related potentials of right-handed patients and control subjects were recorded from 30 electrodes during oddball tasks using consonant-vowel syllables or complex tones. Patients were also assessed using the Positive and Negative Syndrome Scale, the Thought Disorder Index, and the Wechsler Memory Scale.

RESULTS

Paranoid patients did not differ from undifferentiated patients in N1 or P3 amplitude but showed larger N2 at frontocentral sites to phonetic stimuli, as well as larger N2 over left than right hemisphere. Unmedicated patients showed reduced N2, but not N1 or P3, compared to control subjects.

CONCLUSIONS

The N2 findings are consistent with neuropsychological evidence of greater verbal abilities and left hemisphere dominance in paranoid than nonparanoid schizophrenia. The findings also confirm the relationship of P3 to total Brief Psychiatric Rating Scale score, negative symptoms, and verbal associative memory.

Treatment of hypoxemia in obstructive sleep apnea

Many patients suffering from obstructive sleep apnea (OSA) have intermittent oxygen desaturation associated with periods of apnea or hypopnea. Oxygen saturation levels below 90% are considered harmful. Usually, treatment is directed at correcting the apnea, which will in turn prevent hypoxemia. Unfortunately, many patients fail or are not candidates for nasal continuous positive airway pressure (CPAP) or surgical correction of their OSA. Forty-three patients with persistent OSA and nocturnal hypoxemia below 90% who were not candidates for additional surgical or CPAP therapy were treated with nocturnal oxygen supplementation. Standard symptoms associated with OSA and the Epworth Sleepiness Scale (ESS) were recorded before treatment and 30 days after the start of the treatment. In 21 patients, polysomnography studies were performed to compare the Respiratory Disturbance Index (RDI) score and minimum oxygen saturation levels when the patients were breathing room air or breathing 4 L/minute of oxygen by nasal cannula. Subjective symptoms of obstructive sleep apnea improved, and the ESS score significantly decreased after a 30-night treatment with oxygen. Split-night polysomnography showed a significant increase in minimum oxygen saturation during oxygen administration. The RDI did not significantly change with treatment. Oxygen administration for the correction of OSA-related nocturnal hypoxemia was both safe and effective in alleviation of OSA-related symptoms. It also appeared to have a beneficial effect on minimum oxygen saturation levels. Thus, oxygen therapy may be considered a treatment option in patients who fail to comply with CPAP and are not candidates for a surgical procedure.

Application of the S-pyridylethylation reaction to the elucidation of the structures and functions of proteins

Cysteine (Cys) and cystine residues in proteins are unstable under conditions used for acid hydrolysis of peptide bonds. To overcome this problem, we proposed the use of the S-pyridylethylation reaction to stabilize Cys residues as pyridylethyl-cysteine (PEC) protein derivatives. This suggestion was based on our observation that two synthetic derivatives formed by pyridylethylation of the SH group of Cys with either 2-vinylpyridine (2-VP) or 4-vinylpyridine (4-VP), designated as S-beta-(2-pyridylethyl)-L-cysteine (2-PEC) and S-beta-(4-pyridylethyl)-L-cysteine (4-PEC), were stable under acid conditions used to hydrolyze proteins. This was also the case for protein-bound PEC groups. Since their discovery over 30 years ago, pyridylethylation reactions have been widely modified and automated for the analysis of many structurally different proteins at levels as low as 20 picomoles, to determine the primary structures of proteins and to define the influence of SH groups and disulfide bonds on the structures and functional, enzymatic, medical, nutritional, pharmacological, and toxic properties of proteins isolated from plant, microbial, marine, animal, and human sources. Pyridylethylation has been accepted as the best method for the modification of Cys residues in proteins for subsequent analysis and sequence determination. The reaction has also been proposed to measure D-Cys, homocysteine, glutathione, tryptophan, dehydroalanine, and furanthiol food flavors. This integrated overview of the diverse literature on these reactions emphasizes general concepts. It is intended to serve as a resource and guide for further progress based on the reported application of pyridylethylation reactions to more than 150 proteins.

Sensory nerves promote ozone-induced lung inflammation in mice

Genetically manipulated mice exhibiting altered innervation of the airways were used to examine the role of sensory nerves in ozone-induced lung inflammation. Transgenic mice expressing nerve growth factor (NGF) from the lung-specific Clara cell secretory protein (CCSP) promoter exhibit hyperinnervation of the airways by sympathetic and tachykinin-containing sensory nerve fibers. Mice carrying a mutation in the low-affinity NGF receptor (NGFR) gene possess deficits in sensory innervation. CCSP-NGF transgenic mice exhibited a twofold increase in the number of lung lavage neutrophil level whereas NGFR knockout mice exhibited a nearly 50% decrease in neutrophilic inflammation compared with wild-type mice 18 h after ozone inhalation. Treatment with neurokinin receptor antagonists reduced the level of neutrophilic inflammation in both wild-type and CCSP-NGF mice. Examination of lavage fluid cytokine concentrations revealed that 4 h after ozone exposure CCSP-NGF mice produced significantly higher amounts of the chemokine KC than wild-type mice exposed to ozone. The results of this study indicate that sensory nerves are important mediators of ozone-induced inflammation in mice.

Role of LPS and receptor subtypes in the uptake of TNF by the murine lung

Tumor necrosis factor alpha (TNF) is an important mediator in lung injury. The kinetics of TNF uptake by the lung are not completely understood. In this study, we evaluated the role that lipopolysaccharide (LPS) and the two types of TNF receptor (p55 and p75) play in the uptake of circulating murine TNF by the murine lung. TNF radioactively labeled with 125I (I-mTNF) was administered intravenously (2 x 10(6) cpm/mouse) to mice with both receptors (wild-type) or to mice missing one (p55-/- or p75-/-) or both (p55-/- and p75-/-) TNF receptors. Blood to lung non-reversible sequestration (Ki) and reversible uptake (Vi) were measured with multiple-time regression analysis. Uptake by lung of I-mTNF in wild-type mice had reversible and non-reversible components. This uptake was decreased by intratracheal, but not by intravenous, LPS, suggesting modulation by local, rather than systemic, inflammation. The p75-/- deficient mice retained the Ki (saturable, non-reversible) component of TNF uptake, whereas p55-/- deficient mice retained the Vi (saturable, reversible) component of TNF uptake. Both Ki and Vi components of TNF uptake were absent in the lungs of p55-/- p75-/- deficient mice. These studies show that local inflammation inhibits the uptake of circulating I-mTNF by lung and that uptake consists of two distinguishable compartments: reversible uptake mediated by the p75 receptor and non-reversible sequestration mediated by the p55 receptor.

A framework for developing excellence as a clinical educator

The current emphasis on providing quality undergraduate and postgraduate medical education has focused attention on the educational responsibilities of all doctors. There is a greater awareness of the need to train doctors as educators and courses have been set up to satisfy this need. Some courses, such as those on how to conduct appraisal, are specific to one task facing a medical educator. Other courses take a broader view and relate educational theory to practice. In this paper we describe an outcome-based approach in which competence in teaching is defined in terms of 12 learning outcomes. The framework provides a holistic approach to the roles of the teacher and supports the professionalism of teaching. Such a framework provides the basis for the development of a curriculum for teaching excellence. It helps to define important competences for different categories of teachers, communicate the areas to be addressed in a course, identify gaps in course provision, evaluate courses, assist in staff planning and allow individuals to assess their personal learning needs. The framework is presented to encourage wider debate.

Type A behavior and coronary atherosclerosis

OBJECTIVES

To evaluate whether the pathogenesis of type A behavior may involve the premature development of coronary atherosclerosis.

BACKGROUND

Type A or coronary-prone behavior is considered a possible risk factor for the development of coronary heart disease. Premature development of coronary atherosclerosis is suspected to play a role. Utilizing electron beam computed tomography, one can accurately determine the degree of coronary artery calcification, which is reflective of coronary atherosclerosis.

METHODS

We performed a study of 35 men who had no clinical evidence of coronary heart disease. Twenty exhibited severe type A behavior and 15 exhibited type B behavior. All subjects were given an Electron Beam Computed Tomography scan of their coronary arteries and a treadmill electrocardiogram.

RESULTS

Eight of the 20 (40%) type A subjects were found to have coronary calcification compared to none of the type B subjects (P=0.005). The correlation coefficient between type A score and coronary calcium score was 0.39 (P=0.09).

CONCLUSIONS

The pathophysiology by which type A behavior increases the risk for coronary heart disease may involve the premature development of coronary atherosclerosis.

Use of a long-acting inhaled beta2-adrenergic agonist, salmeterol xinafoate, in patients with chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a condition in which continuous bronchodilation may have clinical advantages. This study evaluated salmeterol, a beta-agonist bronchodilator with a duration of action substantially longer than that of short-acting beta-agonists, compared with ipratropium, an anticholinergic bronchodilator, and placebo in patients with COPD. Four hundred and five patients with COPD received either salmeterol 42 microg twice daily, ipratropium bromide 36 microg four times daily, or placebo for 12 wk in this randomized, double-blind, parallel-group study. Patients were stratified on the basis of bronchodilator response to albuterol (> 12% and > 200-ml improvement) and were randomized within each stratum. Bronchodilator response was measured over 12 h four times during the treatment period. Salmeterol provided similar maximal bronchodilatation to ipratropium but had a longer duration of action and a more constant bronchodilatory effect with no evidence of bronchodilator tolerance. Both active treatments were well tolerated. Salmeterol was an effective bronchodilator with a consistent effect over this 12-wk study in patients with COPD, including those "unresponsive" to albuterol. The long duration of action of salmeterol offers the advantage of twice daily dosing compared with the required four times a day dosing with ipratropium.

Prognostic significance of Bcl-2 and p53 expression in advanced laryngeal squamous cell carcinoma

BACKGROUND

Proteins regulating the cell cycle and cell death are frequently abnormally expressed in cancer. Several of these, particularly p53 and Bcl-2, have been widely suggested as possible prognostic markers in diverse human malignancies. Their role in predicting outcome in squamous cell carcinomas of the head and neck is unclear and may depend on the location, stage, and treatment of the tumor.

METHODS

To assess this question specifically for advanced squamous cell carcinoma of the larynx, we studied 69 patients with stage III or IV tumors, all but 6 of whom were treated with surgery plus postoperative irradiation by a single physician. We studied the patients retrospectively to test the association between expression of Bcl-2 and p53, as assessed by immunohistochemistry, with treatment outcome and survival.

RESULTS

Twenty of the 69 patients died from their tumor (poor outcome); the rest were alive and tumor free at the last follow-up or died of unrelated causes without clinical tumor recurrence (good outcome). Fourteen tumors had detectable Bcl-2 expression, including 8 scored as overexpressors. Thirty-nine tumors overexpressed p53. Expression of neither Bcl-2 nor p53 was associated with outcome, overall survival, or disease-free survival. Only tumor stage was significantly associated with outcome and disease-free survival.

CONCLUSION

These data indicate that assessing expression of p53 or Bcl-2 is unlikely to be prognostically useful for surgically treated advanced laryngeal carcinoma.

Preclinical evaluation of pharmacokinetic-pharmacodynamic rationale for oral CR metformin formulation

We examined the pharmacokinetic (PK) and pharmacodynamic (PD) rationales to develop controlled release (CR) formulations of metformin. Unrestrained diabetic rats received the drug as intravenous bolus (i.v.), oral solution (p.o.), intra-duodenal bolus, 4-h infusion, or intra-colonic bolus. In addition, we developed two CR-gastroretentive dosage forms (CR-GRDF) that released the drug over 3 or 6 h (in vitro), and retained in the rats' stomach for 8-10 h. Metformin exhibited flip-flop PK. The colonic absorption was low but sustained and was associated with highly variable glucose-lowering effects, thus providing a PK rationale to develop CR-GRDF. In addition, the glucose-lowering effect was greater following p.o. vs. i.v. administration, despite equivalent AUC, indicating a first pass PD effect, thus, adding a PD rationale to develop metformin CR-GRDF. When administered to the diabetic rats, CR-GRDFs produced bioavailability and extent of glucose-lowering effects that were similar to those of the duodenal infusion and p.o. metformin administration. These findings are attributed to the adsorption of metformin to the intestine that yields slow and prolonged absorption even following p.o. administration of drug solution. The data indicates that unless the CR formulation could significantly extend the absorption period, it is not likely to improve glucose-lowering efficacy.

Nutritional and health benefits of soy proteins

Soy protein is a major component of the diet of food-producing animals and is increasingly important in the human diet. However, soy protein is not an ideal protein because it is deficient in the essential amino acid methionine. Methionine supplementation benefits soy infant formulas, but apparently not food intended for adults with an adequate nitrogen intake. Soy protein content of another essential amino acid, lysine, although higher than that of wheat proteins, is still lower than that of the milk protein casein. Adverse nutritional and other effects following consumption of raw soybean meal have been attributed to the presence of endogenous inhibitors of digestive enzymes and lectins and to poor digestibility. To improve the nutritional quality of soy foods, inhibitors and lectins are generally inactivated by heat treatment or eliminated by fractionation during food processing. Although lectins are heat-labile, the inhibitors are more heat-stable than the lectins. Most commercially heated meals retain up to 20% of the Bowman-Birk (BBI) inhibitor of chymotrypsin and trypsin and the Kunitz inhibitor of trypsin (KTI). To enhance the value of soybeans in human nutrition and health, a better understanding is needed of the factors that impact the nutrition and health-promoting aspects of soy proteins. This paper discusses the composition in relation to properties of soy proteins. Also described are possible beneficial and adverse effects of soy-containing diets. The former include soy-induced lowering of cholesterol, anticarcinogenic effects of BBI, and protective effects against obesity, diabetes, irritants of the digestive tract, bone, and kidney diseases, whereas the latter include poor digestibility and allergy to soy proteins. Approaches to reduce the concentration of soybean inhibitors by rearrangement of protein disulfide bonds, immunoassays of inhibitors in processed soy foods and soybean germplasm, the roles of phytoestrogenic isoflavones and lectins, and research needs in all of these areas are also discussed. This integrated overview of the widely scattered literature emphasizes general concepts based on our own studies as well as recent studies by others. It is intended to stimulate interest in further research to optimize beneficial effects of soy proteins. The payoff will be healthier humans and improved animal feeds.

Improved intestinal absorption of sulpiride in rats with synchronized oral delivery systems

The goals of this study were to examine whether formulations, capable of releasing sulpiride (SP) in synchrony with the p-Glycoprotein (P-gp) inhibitors, verapamil (Ver) or quinidine (Qn) can increase SP relative bioavailability and to suggest a rationale approach for oral administration of SP. Jejunum of anesthetized rats was perfused with 200 or 400 microg/ml of SP either alone or together with 98 microg/ml of Ver. It was observed that while an increasing SP concentration did not cause an increase in SP blood levels, the addition of Ver or Qn to the perfusion solution caused a profound increase in SP absorption. Erodible matrix tablets, exhibiting a range of erosion rates, were prepared by manipulating the ratios of hydroxypropylmethylcellulose (HPMC) in the matrices. The tablets were designed to release the low water soluble SP and the highly water soluble Qn concomitantly over 1, 2 or 4 h. In all cases, the synchronous release increased SP bioavailability after intra-intestinal administration. The increase varied from 2.6- to 3.9-fold for the fast and the slow release formulations, respectively (compared with a control administration of a powdered mixture of SP and Qn). It is speculated that the poor oral bioavailability of SP was caused by brush border P-gp efflux. Synchronous release delivery systems of SP containing also the P-gp inhibitor Qn were able to increase SP bioavailability after intestinal administration in the rat. It is concluded that oral bioavailability of poorly absorbed drugs, in which absorption is restricted by gut wall secretory transport, may be improved by formulating them with functional adjuvants in synchronous release drug carriers.

Potential short-term economic benefits of improved glycemic control: a managed care perspective

OBJECTIVE

There are limited data relating glycemic control to medical costs among patients with diabetes. The goal of this study was to examine the potential impact of improved glycemic control on selected short-term complications of diabetes and associated costs in a managed care setting.

RESEARCH DESIGN AND METHODS

Using a retrospective cohort design and automated databases from January 1994 to 30 June 1998, adult members of the Fallon Clinic who were diagnosed with diabetes were identified and assigned to one of three study groups based on each patient's mean HbA1c level: good control (<8%), fair control (8-10%), and poor control (> 10%) groups. Inpatient (hospital or skilled nursing facility) admissions for selected acute (short-term) complications, represented by selected infections, hyperglycemia, hypoglycemia, and electrolyte disturbances, and the associated medical charges were evaluated across the three HbA1c groups. Multivariate analyses were used to control for differences in several potential confounding factors among the study groups. All findings were expressed on a 3-year basis.

RESULTS

Of 2,394 patients with diabetes, approximately 10% (251) had at least one inpatient stay for a short-term complication, accounting for 447 admissions. Over 3 years, the adjusted rate of inpatient treatment ranged from 13 per 100 patients with good glycemic control to 16 per 100 patients with fair glycemic control and 31 per 100 patients with poor glycemic control (P < 0.05). The corresponding mean adjusted charges were approximately $970, $1,380, and $3,040, respectively Among the 30% of the study population with long-term diabetic complications, the results were more marked; the adjusted admissions per 100 patients (mean charges) were estimated to be 30 ($2,610), 38 ($3,810), and 74 ($8,320) over 3 years for patients with an HbA1c of <8, 8-10, and > 10%, respectively.

CONCLUSIONS

In typical practice, better glycemic control is associated with a reduced rate of admission for selected short-term complications and, therefore, reduced medical charges for these complications over a 3-year period. The potential short-term economic benefits are important to consider when making decisions regarding the adoption and use of new interventions for the management of diabetes.

Tumor necrosis factor receptor deficiency alters matrix metalloproteinase 13/tissue inhibitor of metalloproteinase 1 expression in murine silicosis

Murine exposure to silica is associated with enhanced tumor necrosis factor alpha (TNF-alpha) expression and matrix deposition. The regulation of TNF is mediated through TNF receptor (TNFR) activation of transcription factors. In the present work we have studied the importance of the individual TNFR in silica-induced lung inflammation and matrix deposition in mice. We studied RNA expression of TNF, alpha1(I) collagen, interstitial collagenase (MMP-13), and its inhibitor (TIMP-1) in the lungs of silica-treated mice. Furthermore, we correlated MMP-13/TIMP-1 RNA abundance with activation of the transcription factors AP-1 and NF-kappaB in the lungs of C57BL/6 mice, and of mice deficient in one of the two types of TNFR (p55(-/-) or p75(-/-)), exposed to silica (0.2 g/kg) or saline by intratracheal instillation. Animals were killed 28 d after exposure and lung hydroxyproline (HP), TNF, alpha1(I) collagen, MMP-13, and TIMP-1 RNA abundance was measured. AP-1 and NF-kappaB activation was studied by gel-shift assays. Compared with C57BL/6 mice, p55(-/-) and p75(-/-) mice significantly (*p < 0.05) decreased lung HP accumulation in response to silica. All murine strains enhanced TNF and alpha1(I) collagen mRNA in response to silica. Enhanced (p < 0.05) MMP-13 RNA expression was also observed in all murine strains in response to silica. Enhanced (p < 0.05) TIMP-1 RNA expression was observed in C57BL/6 mice, but not in p55(-/-) or p75(-/-) mice, in response to silica. NF-kappaB activation was observed in all murine strains, whereas AP-1 activation was observed only in C57BL/6 mice after silica treatment. These data suggest that TNFR deletion modifies MMP-13/ TIMP-1 expression in favor of matrix degradation.

Tracer studies on the incorporation of [2-14C]-DL-mevalonate into chlorophylls a and b, alpha-chaconine, and alpha-solanine of potato sprouts

Chlorophyll and glycoalkaloids are synthesized in different parts of the potato plant including leaves, tubers, and sprouts. Although light stimulates the biosynthesis of both constituents, the question of whether the two biosynthetic pathways are under the same genetic control has not been resolved. This study investigated the dynamics of incorporation of labeled [2-(14)C]-DL-mavalonate into chlorophyll a, chlorophyll b, and the glycoalkaloids alpha-chaconine and alpha-solanine in potato sprouts after 7 and 14 days of storage in the light and in the dark. No chlorophyll synthesis occurred in the dark. Fractionation of the "glycoalkaloid" extract followed by high-performance liquid chromatography produced four peaks. The fractions were collected and analyzed for radioactivity. About 80% of the radioactivity resided in fraction 1, the composition of which is unknown. Two of the fractions, with 1-14% of the original label, were alpha-chaconine and alpha-solanine. The radioactivity derived from mevalonate largely resides in unidentified compound(s) eluting as a single peak on the HPLC column before the peaks associated with the glycoalkaloids. The specific radioactivity of alpha-chaconine and alpha-solanine increased approximately 2-fold in going from 7 to 14 days of exposure in the light and in the dark. These and additional observations point to the near identity of the dynamics of biosynthesis of the two glycoalkaloids. These data also implicate a non-mevalonate pathway for the synthesis of both chlorophylls and the glycoalkaloids and are consistent with independent genetic control of the concurrent formation of the two classes of compounds during greening of potatoes.

Economic burden of chronic obstructive pulmonary disease. Impact of new treatment options

The incidence, morbidity and mortality of chronic obstructive pulmonary disease (COPD) is rising throughout the world. The total economic cost of COPD in the US in 1993 was estimated to be over $US15.5 billion, with $US6.1 billion for hospitalisation, $US4.4 billion for physician and other fees, $US2.5 billion for drugs, $US1.5 billion for nursing home care and $US1.0 billion for home care. Office visits, hospital outpatient visits and emergency department visits accounted for 17.3% of the direct costs for COPD in the US. When stratified by severity, COPD treatment costs strongly correlate with disease severity. The American Thoracic Society, the European Respiratory Society and the British Thoracic Society have developed guidelines for the pharmacological treatment of COPD. However, the guidelines establish inhaled bronchodilators (anticholinergic agents and beta 2-adrenergic agonists) as the mainstay of therapy for patients with COPD. The guidelines were not based on cost analyses and thus are not a priori cost-effective guidelines. Since the publication of these guidelines, several new pharmacological products have been approved for use in patients with COPD including a combination of an anticholinergic and selective beta 2-adrenergic agonist [ipratropium/salbutamol (albuterol)] and a long-acting beta 2-adrenergic agonist (salmeterol). Both products are effective bronchodilators in COPD. The purpose of this report is to place these new agents in an updated pharmacological guideline scheme, utilising recently published data on clinical efficacy as well as pharmacoeconomics. The annualised healthcare costs were computed to be $US788/patient/year for the combination ipratropium/salbutamol inhaler and $US1059/patient/year for salmeterol (1999 values). Based upon an improved understanding of the complexity of COPD, the response of patients to newer bronchodilators (given individually or in combination), and recent pharmacoeconomic data for COPD treatment, a new treatment algorithm with associated costs is proposed. The use of an algorithm, based on medical and pharmacoeconomic data, will improve lung function in patients with COPD, improve patient satisfaction (e.g. quality of life, dyspnoea) and outcomes (e.g. exacerbations). It will also result in a positive effect on healthcare costs.