Contractile response of canine gallbladder and sphincter of Oddi to substance P and related peptidesin vitro

Substance P (SP) is a neurotransmitter peptide that is widely distributed in the body. Since SP has been demonstra in the gallbladder (GB) and bile ducts of dogs, it may have a role in biliary motility. The objective of this study was to examine the effect of SP on the GB and sphincter of Oddi (SOD) of dogs in vitro,to evaluate the structure-activity relationship of SP, and to compare the contractile effect of SP with that of cholecystokinin octapeptide (CCK-8) and acetylcholine (Ach). Isolated longitudinal strips of GB and SOD from dogs were suspended in oxygenated Krebs buffer and the isometric tension responses to various doses of CCK-8, Ach, SP, and SP homologs [SP-free acid (SPFA), Octa-SP (O-SP), physalaemin (PHY)] were measured. We found that all the SP homologs, other than SPFA, stimulated GB and SOD contractions in vitroin a dose-dependent manner. The potency of SP and its homologs on GB and SOD was SP PHY > O-SP; SPFA was without effect. CCK-8 was significantly more effective than SP on GB contraction, but unlike SP, CCK had no effect on SOD. The maximum contraction achieved by Ach was 1.3 (SOD) to 2.3 (GB) times greater than that achieved by SP, but the ED ₅₀ of SP was approximately 100- to 200-fold lower than that of Ach. The contractile effect of SP was partially blocked by 10 ^–5 M atropine. We suggest from the above results that contractile effects of SP on the dog GB and SOD are probably mediated through binding to specific SP receptors that require the C-terminal amino group and the C-terminal penta-peptide sequence in order to be most effective.Supported by grants from the National Institute of Health (RO1 AM 15241, PO1 DK 35608, and CA 38651).Part of this work was presented at the Federation of American Society for Experimental Biology held in St. Louis, Missouri, April 13, 1986.     

The effect of a disinfectant/ coolant irrigant on microbes isolated from dental unit water lines

The purpose of this study was to assess water samples from a hospital dental clinic to determine whether a disinfectant/coolant irrigant containing chlorhexidine (Lines, ^tm Micrylium Laborator-ies) affects the presence of microbial organisms in dental unit waterlines. Water samples from three hospital dental operatories were collected at baseline and after overnight treatment with a disinfectant-containing irrigant followed by sterile water irrigation. Saliva of treated patients and sterile water rinse specimens were collected from the waterlines of these operatories for three consecutive days, then weekly for eight weeks after treatment. Specimens were cultured to identify total heterotrophic plate counts as well as presence of Pseudomonas aeruginosa and Candida species. Baseline organism counts varied from 10³ to 10⁵ colony-forming units per milliliter. After treatment, no organisms were detected in waterline discharge. Decontamination of dental unit waterlines is possible using a disinfectant/irrigant followed by sterile water irrigation. The potential for contamination of the lines from patients' saliva may have been reduced due to use of anti-retraction valves and the disinfectant/sterile water irrigation, as conducted in this study.     

Ciclopirox olamine: A hydroxypyridone antifungal agent

Ciclopirox olamine is a hydroxypyridone antifungal agent that is structurally unrelated to the common imidazole derivatives or other antifungals (Fig 1). Its antimicrobial and clinical activity has been extensively reviewed elsewhere.¹ In this paper, a review of recent investigations is provided, with an emphasis on new pharmacologic data.     

Implications of neuropsychological test results of women in a new phase of anorexia nervosa

A study involving 10 female anorectics who satisfied DSM-III-R (American Psychiatric Association, 1987) criteria in a new phase of outpatient treatment and 10 healthy female controls matched for age, education, social class, premorbid IQ and geographical habitation, were administered a battery of well-known neuropsychological tests and rating scales. Personal details concerning subjects' weight history and parents' occupations were also recorded. Significant evidence was found to suggest a difference between the anorectics and the controls on a number of tests and scales. In particular, anorectics performed worse on the third trial of the Auditory Verbal Learning Test and on the Rey-Osterreith Complex Figure Test (Delayed Recall Trial) possibly implying impairment of the right hemisphere considered to be responsible, in part, for visuospatial ability. This was believed to be one of the reasons for distortion of body image in anorexia nervosa. Strong evidence was also found in support of the coexistence of obsessionality and depression in anorexia nervosa. Since there is growing evidence implicating the caudate nucleus for the obsessionality in obsessive-compulsive disorder, it was proposed that this association might also be likely to explain the obsessionality in anorexia nervosa, thus supporting hypotheses that propose an organic origin for the condition.     

A comparison of critical thinking skills in standard and non-standard entry diploma students

Critical thinking is often seen as the hallmark of the educated professional.The conceptualization and measurement of critical thinking have been topics of much debate for over 70 years. This study reports a small scale comparative study of critical thi nking skills in standard and non-standard entry diploma students. A significantdifference in critical thinking skills between these groups at the point of entry was observed. There were no significant differences in critical thinking skills between the start of the course and the end of the common foundation course for both groups. This finding is consistent with many other studies investigating critical thinking in nurse education. The implications of these findings and the wider issue of the measur ement of critical thinking are discussed.     

Posterior marginal mandibulectomy in the management of cancer of the oral cavity and oropharynx

OBJECTIVE: To review a single institution's experience with posterior marginal (ramus) mandibulectomy for mandibular preservation in the management of patients with squamous cell carcinoma of the retromolar trigone or oropharynx. To review the history and surgical technique with emphasis on functional as well as oncologic outcomes. STUDY DESIGN AND SETTING: Retrospective review at a tertiary care academic referral center from 1996 to 2002. RESULTS: Between 1996 and 2002, 382 patients with squamous cell carcinoma of the oral cavity and oropharynx were surgically treated at the Loyola University Medical Center. Medical records were reviewed and 152 patients were identified who had some form of mandibular procedure (segmental resection, marginal resection, or mandibulotomy) performed in conjunction with their tumor resection. Eighteen posterior marginal mandibulectomies were performed for primary cancers of the retromolar trigone, tonsillar fossa, and/or base of the tongue. All patients received adjuvant radiotherapy. Bone invasion of the marginal mandibulectomy specimens by squamous cell carcinoma was observed in 2 cases, neither of which developed a local recurrence. Mean and median overall survivals were 41.4 and 37.5 months, respectively. Functional outcomes were determined by administering the University of Washington Quality of Life instrument administered at 12 months. Patients reported significant alterations in chewing, but all were able to maintain satisfactory oral intake and no patient required a gastrosotomy tube. CONCLUSIONS: A posterior osteotomy of the mandibular ramus is a useful adjunct in the surgical treatment of cancer of the retromolar trigone or oropharynx. Negative surgical margins can be obtained even with focal invasion of mandibular bone. The loss of bone in this area does not significantly affect patients' appearance. Patients report deterioration in chewing following this procedure but are able to maintain a diet of solid food.     

Children who withdraw consent for elective surgery

Parents and legal guardians have authority to consent to medical treatment on behalf of minors. Recently, the concept of emerging competence has been popularized, whereby a child may achieve sufficient understanding and maturity to enable him/her to make a wise choice in his/her own interests. Although there are undoubted merits in involving children in their medical treatment, the ultimate legal authority for consent rests with parents and guardians acting on the advice of doctors and in the child's best interests. We describe two cases in which children withdrew their consent to elective surgery, despite the help and encouragement of their parents and doctors. Surgery was cancelled rather than use force to induce anaesthesia. In practice, it seems that a child must demonstrate a greater maturity and understanding to refuse medical treatment than to agree to it. Some advice is given to clinicians facing similar situations.