Effects of chronic amitriptyline administration on saliva from the parotid and submandibular glands of the rat

The effect of prolonged treatment with amitriptyline on the secretory activity of rat salivary glands evoked by parasympathetic nerve stimulation and isoprenaline administration has been studied. Low doses of amitriptyline (10 mg/kg per day for 2 or 4 weeks), did not significantly affect salivary flow evoked by either parasympathetic nerve or isoprenaline stimulation. Higher doses of amitriptyline (50 mg/kg/day for 2 or 4 weeks) however, markedly decreased parasympathetic-evoked salivary secretion (flow and volume) from both parotid and submandibular glands, while isoprenaline-evoked secretions were unaffected. Sodium, potassium, and calcium concentrations of nerve-elicited or isoprenaline-evoked saliva were not significantly altered by amitriptyline treatment. Protein concentration and amylase activity of nerve-elicited parotid saliva were, however, greatly increased by chronic amitriptyline administration. Possible mechanisms for drug-induced increase in nerveelicited salivary protein concentration include changes in cholinergic receptor binding, release of neuropeptides and variations in phosphatidylinositol turnover, which need further study.     

Eighteen-month Coronal Caries Incidence in North Carolina Older Adults

In this longitudinal study of a random sample of North Carolinians over the age of 65 and living in their homes, 325 blacks and 280 whites were examined and interviewed 18 months after baseline examinations. Coronal caries incidence was greater among whites than blacks. The increment due to teeth becoming root fragments were similar for both races; however, there were more newly crowned teeth among whites. Newly crowned surfaces were not used as part of the caries increment in logistic regression models to investigate potential risk predictors. For blacks, caries development over the 18-month period was associated with a higher lactobacillus score and more coronal caries at baseline, more previously filled coronal surfaces, and lack of active membership in clubs or other groups. For whites, having no self-reported tooth sensitivity, having a lower socioeconomic index score, taking antihistamine medications at baseline, and having the perception of more problems after the age of 40 than before were all associated with the development of coronal caries.     

Difficult or Impossible Ventilation after Sufentanil-induced Anesthesia Is Caused Primarily by Vocal Cord Closure

Introduction: Opioid-induced rigidity often makes bag-mask ventilation difficult or impossible during induction of anesthesia. Difficult ventilation may result from chest wall rigidity, upper airway closure, or both. This study further defines the contribution of vocal cord closure to this phenomenon.

Methods: With institutional review board approval, 30 patients undergoing elective cardiac surgery participated in the study. Morphine (0.1 mg/kg) and scopolamine (6 micro gram/kg) given intramuscularly provided sedation along with intravenous midazolam as needed. Lidocaine 10% spray provided topical anesthesia of the oropharynx. A fiberoptic bronchoscope positioned in the airway photographed the glottis before induction of anesthesia. A second photograph was obtained after induction with 3 micro gram/kg sufentanil administered during a period of 2 min. A mechanical ventilator provided 10 ml/kg breaths at 10/min via mask and oral airway with jaw thrust. A side-stream spirometer captured objective pulmonary compliance data. Subjective airway compliance was scored. Pancuronium (0.1 mg/kg) provided muscle relaxation. One minute after the muscle relaxant was given, a third photograph was taken and compliance measurements and scores were repeated. Photographs were scored in a random, blinded manner by one investigator. Wilcoxon signed rank tests compared groups, with Bonferroni correction. Differences were considered significant at P <0.05.

Results: Twenty-eight of 30 patients exhibited decreased pulmonary compliance and closed vocal cords after opioid induction. Two patients with neither objective nor subjective changes in pulmonary compliance had open vocal cords after opioid administration. Both subjective and objective compliances increased from severely compromised values after narcotic-induced anesthesia to normal values (P = 0.000002) after patients received a relaxant. Photo scores document open cords before induction, progressing to closed cords after the opioid (P = 0.00002), and opening again after a relaxant was administered (P = 0.00005).     

Fibroblast subpopulations in intra-oral wound healing

The objective of this study was to characterize fibroblasts at sequential time points during intra-oral wound healing in the rat. Experimental wounds were made at several time points in the mucoperiosteum of the palate of 35-day-old Wistar rats. Fibroblasts were cultured from the biopsies under standard conditions for the same number of passages. The expression of the integrin subunits alpha 1, alpha 6, and beta 1; and the intermediate filaments alpha-smooth muscle actin and vimentin were analyzed by flow cytometry. Western blot analysis was performed at 0, 8, and 60 days postwounding to confirm the expression of both intermediate filaments. The phenotypic profiles of fibroblasts cultured from subsequent stages in the wound healing process differed considerably. We conclude that distinct fibroblast phenotypes can be isolated from different stages in wound healing. These phenotypes remained stable during in vitro culturing. In addition, cryosections of the wound areas were made at identical time points and were immunohistochemically stained for the same antigens. The immunohistochemical staining correlated well to the flow-cytometric data. These results suggest the occurrence of multiple subpopulations of fibroblasts with a specialized function during wound healing. We hypothesize that undesirable consequences of wound healing might be prevented through the modulation of specific fibroblast subpopulations.     

Synthesis of 3-(3-pyridyl)- and 3-(3-benzo[b]thienyl)-D-alanine

The DL-arylamino acid ethyl ester derivatives of β-(3-pyridyl)-DL-alanine, and β-(3-benzo[b]thienyl)-DL-alanine were synthesized by diethyl acetamidomalonate condensation with the respective arylmethyl halides followed by partial hydrolysis to the monoethyl ester and decarboxylation. Each derivative was enzymatically resolved to a separable mixture of the corresponding N-acetyl-L-amino acid and the unchanged D amino acid derivative. Acidic hydrolysis of the latter gave the corresponding D-amino acid, the optical purity of which was established by HPLC analysis of the 2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl isothiocyanate (GITC) derivative. The free D amino acids were converted to D-BOC derivatives by reaction with di-tert-butyldicarbonate in tert-butyl alcohol, water and sodium hydroxide.     

Eligible Veterans'' Choice Between VA-covered and Non-VA-covered Dental Care

Veterans who were eligible for dental care in Department of Veterans Affairs (VA) facilities at no monetary cost responded to a mailed questionnaire. Seventy-one percent were aware that they were actually eligible for VA dental care. However, only 48 percent reported the VA as their only or primary source of dental care. Eligibility status, perceived quality of VA dental care, use of VA medical care, perception that one's income meets expenses, and perceived need for dental care were significant correlates of using the VA as one's current source of dental care. Level of formal education, perception that one's income meets expenses, transportation pattern, geographic distance from a VA facility, and eligibility status were significant correlates of using the VA as one's current medical care source. Research on VA utilization offers the opportunity to study issues of access to, and use of, a large public health care system whose patients largely receive care at no monetary cost. Veterans' use of VA dental and medical care is apparently influenced by a wide variety of factors, ranging from barriers to access to non-VA systems, to characteristics of the VA delivery system itself, to need for treatment.