Pulp capping: conserving the dental pulp--can it be done? Is it worth it?

Emphasis has shifted from the "doomed" organ concept of an exposed pulp to one of hope and recovery. The era of vital-pulp therapy has been greatly enhanced with the introduction of calcium hydroxide (CH) products. The sequence of events leading to dentinal bridge formation with various CH formulas is detailed. Those factors usually considered liabilities to direct pulp capping (pulps cariously exposed, contaminated by saliva, previously carious or restored, periodontally involved, or from older patients and primary teeth) are disputed. Those factors that must be considered to improve the success rate of pulp capping are emphasized: control bleeding, make certain the CH contacts vital-pulp tissue, minimize dentinal chip invasion, avoid embolization of CH particles, and be aware of the depth of penetration of the chemical cautery effect.     

The effect of nitroglycerin on response to tracheal intubation. Assessment by radionuclide angiography

The effect of intravenous (IV) nitroglycerin (NTG) on perioperative myocardial ischemia as detected by single pass radionuclide angiocardiography was studied in 20 patients scheduled for elective coronary artery bypass grafting (CABG). Ten patients, selected at random, received IV NTG 1 microgram.kg-1.min-1 (NTG group) and 10 others, IV saline (control group). Anesthetic induction consisted of midazolam 0.2 mg.kg-1, vecuronium 0.1 mg.kg-1, and 50% N2O in O2. ECG leads I, II, and V5 were monitored for ST segment changes. Single pass radionuclide angiocardiography (RNA) was performed at 5 times: prior to induction, prior to tracheal intubation, and at 1, 3.5, and 6 min following intubation. The presence of new regional wall motion abnormalities (RWMA) was determined from each RNA study as compared with the preinduction measurement. Apart from one patient in the control group who developed a new "v" wave after intubation, there was no evidence of ischemia by pulmonary capillary wedge pressure. No ECG evidence of ischemia was detected in any patient. Despite this, new regional wall motion abnormalities were observed in 3 patients in the control group and 1 patient in the NTG group. Blood pressure and heart rate responses of patients with new RWMA were not significantly different from other patients. The low incidence of ischemia in this population precludes a definitive statement regarding the efficacy of IV NTG, but the lower incidence of RWMA in the NTG group suggests a protective effect.     

Comparative distribution,pharmacokinetics and placental permeabilities of all-trans-retinoic acid, 13-cis-retinoic acid,all-trans-4-oxo-retinoic acid,retinyl acetate and 9-cis-retinal in hamsters

Pregnant hamsters were given a single oral dose (35 mol/kg) of all-trans-retinoic acid, 13-cis-retinoic acid, all-trans-4-oxo-retinoic acid, 9-cis-retinal or all-trans-retinyl acetate during the early primitive streak stage of development. The radioactivity associated with the acidic retinoids was distributed to all tissues sampled (including placenta and fetus), with the largest accumulation in the liver and the least accumulation in fat. Radioactivity from 9-cis-retinal or retinyl acetate concentrated in the liver and lung. The all-trans-retinoic acid was oxidized in vivo to all-trans-4-oxo-retinoic acid and isomerized to 13-cis-retinoic acid; 13-cis-retinoic acid was oxidized to 13-cis-4-oxo-retinoic acid and isomerized to all-trans-retinoic acid. No parent 9-cis-retinal or retinyl acetate could be detected in maternal plasma. Plasma concentrations of the parent acidic retinoids reached their maxima within 60 min and then followed exponential decay. Of all the retinoids examined here, 13-cis-retinoic acid showed the largest area under the plasma curve, the slowest clearance and the longest elimination t 1/2. Total plasma radioactivity, consisting of unidentified metabolites, remained elevated at 4 days after dosing. Maternal peak circulating concentrations of the parent retinoids, total radioactivity, plasma pharmacokinetic parameters or the total concentrations of residual radioactivity in fetal tissues could not be correlated with the differential teratogenic potencies of these retinoids.     

Severe rhinosinusitis

Rhinosinusitis is diagnosed frequently in clinical practice, but the term may in fact encompass a wide spectrum of diseases. Inflammation of the nasal and sinus mucosa can arise from various causes and lead to different sequelae. Moreover, the term rhinosinusitis is more accurate than sinusitis. Causes range from a viral infection leading to the common cold to an invasive, fungal infection. An accurate diagnosis is important because effective therapy is available if recognized early and if specific therapy is used. Importantly, there is a close relationship between upper and lower airway disease and each have unique structural and functional differences that make an understanding of rhinosinusitis important not only for upper airway disease, but also for the management of asthma. All too often, rhinosinusitis becomes chronic and this becomes a challenge because medical therapy may not be sufficient to control disease. Finally, we should note that the differential diagnosis of rhinosinusitis is extensive and physicians should place heavy emphasis not only on the history, but also on appropriate imaging studies. A normal exam does not rule out the possibility or rhinosinusitis. Finally, we should emphasize that effective treatment is dependent on the etiology of the symptoms but also dependent on whether it is acute or chronic.     

Cognitive-behavioral treatment of late-life generalized anxiety disorder

This study addressed the efficacy of cognitive-behavioral therapy (CBT), relative to minimal contact control (MCC), in a sample of 85 older adults (age 60 years and over) with generalized anxiety disorder (GAD). All participants completed measures of primary outcome (worry and anxiety), coexistent symptoms (depressive symptoms and specific fears), and quality of life. Results of both completer and intent-to-treat analyses revealed significant improvement in worry, anxiety, depression, and quality of life following CBT relative to MCC. Forty-five percent of patients in CBT were classified as responders, relative to 8% in MCC. Most gains for patients in CBT were maintained or enhanced over 1-year follow-up. However, posttreatment scores for patients in CBT failed to indicate return to normative functioning.     

The effect of ventilation on spectral analysis of heart rate and blood pressure variability during exercise

Heart rate variability (HRV) and systolic blood pressure variability (BPV) during incremental exercise at 50, 75, and 100% of previously determined ventilatory threshold (VT) were compared to that of resting controlled breathing (CB) in 12 healthy subjects. CB was matched with exercise-associated respiratory rate, tidal volume, and end-tidal CO(2) for all stages of exercise. Power in the low frequency (LF, 0.04-0.15 Hz) and high frequency (HF, >0.15-0.4 Hz) for HRV and BPV were calculated, using time-frequency domain analysis, from beat-to-beat ECG and non-invasive radial artery blood pressure, respectively. During CB absolute and normalized power in the LF and HF of HRV and BPV were not significantly changed from baseline to maximal breathing. Conversely, during exercise HRV, LF and HF power significantly decreased from baseline to 100% VT while BPV, LF and HF power significantly increased for the same period. These findings suggest that the increases in ventilation associated with incremental exercise do not significantly affect spectral analysis of cardiovascular autonomic modulation in healthy subjects.     

The use of urine proteomic and metabonomic patterns for the diagnosis of interstitial cystitis and bacterial cystitis

The advent of systems biology approaches that have stemmed from the sequencing of the human genome has led to the search for new methods to diagnose diseases. While much effort has been focused on the identification of disease-specific biomarkers, recent efforts are underway toward the use of proteomic and metabonomic patterns to indicate disease. We have developed and contrasted the use of both proteomic and metabonomic patterns in urine for the detection of interstitial cystitis (IC). The methodology relies on advanced bioinformatics to scrutinize information contained within mass spectrometry (MS) and high-resolution proton nuclear magnetic resonance (1H-NMR) spectral patterns to distinguish IC-affected from non-affected individuals as well as those suffering from bacterial cystitis (BC). We have applied a novel pattern recognition tool that employs an unsupervised system (self-organizing-type cluster mapping) as a fitness test for a supervised system (a genetic algorithm). With this approach, a training set comprised of mass spectra and 1H-NMR spectra from urine derived from either unaffected individuals or patients with IC is employed so that the most fit combination of relative, normalized intensity features defined at precise m/z or chemical shift values plotted in n-space can reliably distinguish the cohorts used in training. Using this bioinformatic approach, we were able to discriminate spectral patterns associated with IC-affected, BC-affected, and unaffected patients with a success rate of approximately 84%.     

Chromosome mapping of cell membrane antigens expressed on activated B cells

Hybrids formed by fusion of either human acute lymphoblastic or chronic lymphocytic leukemia cells and the mouse myeloma P3.X63.Ag8/653 have been used to show that the expression of two cell surface antigens, Bp37 and p76, associated with B cell activation and detected by the monoclonal antibodies BB1 and BB2, respectively, segregate with human chromosomes 12 and 19, respectively. Another antigen expressed on activated B cells (p24) also maps to chromosome 12 (Katz et al., Eur. J. Immunol. 1984. 13: 1008) which is of interest in the light of the frequent involvement of this chromosome in certain B cell leukemias and lymphomas.     

Changes in catecholamine concentrations in the hypothalamus and region of the midbrain raphe in male and female rats during postnatal development

To investigate possible sex differences in central catecholaminergic systems, the concentrations of dopamine (DA) and 3,4-dihydroxyphenylacetic acid (DOPAC) were measured by high-performance liquid chromatography with electrochemical detection in the hypothalamus-preoptic area (H-POA) and midbrain raphe (MR) region of male and female rats throughout postnatal development. Other than a small but significant sex difference in DA concentration in the MR at 36 h (higher in females), the results showed that there were no sex differences in the concentrations of DA or DOPAC at any age in either brain region. The developmental profiles of the concentrations of DA and DOPAC showed that DAergic systems in the H-POA are immature at birth, with concentrations increasing steadily until 80 days of age, but in the MR concentrations reach a maximum at 20 days of age; a situation which is perhaps a reflection of differing monoamine metabolism in the two areas.     

Controlled clinical comparison of plastic versus glass bottles of BacT/ALERT PF medium for culturing blood from children

The plastic pediatric BacT/ALERT (bioMérieux, Durham, N.C.) PF (PPF) is a new nonvented aerobic culture medium in a clear plastic bottle designed to prevent breakage. We compared the performance of the new PPF bottle to that of the present glass BacT/ALERT PF bottle for the recovery of microorganisms as well as for the time to detection of growth in samples of blood obtained for culture from children. We found that the PPF and PF bottles were comparable for recovery of microorganisms and that the safety advantage of plastic bottles can be achieved without compromising performance.