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Biomedical subjects

R A Baker

Publications and source records attributed to R A Baker.

At least 127 records · Page 7Linked to original sources
PubMed1966

Auxin activity of substituted benzoic acids and their effect on polar auxin transport.

Six dichloro-, 3 trichloro-, 2 triiodo-, and 3 heterosubstituted benzoic acids (amiben, dinoben, dicamba), and N-1-naphthylphthalamic acid have been tested for effects on growth and on polar auxin transport. Growth activity with and without kinetin was measured by effects on fresh and dry weights of 30-day cultures of fresh tobacco pith. Transport inhibition was measured by following uptake and output of IAA-2-(14)C through 10 mm bean epicotyl sections. The distribution of callus growth on vascularized tobacco stem segments was also observed. Avena first internode extension assays established the relative activities: dicamba > amiben > dinoben suggested by pith growth results. Growth effects of active compounds were similar with and without kinetin, except that amiben was less active with kinetin, while 2,3,6-trichlorobenzoic acid was more active with kinetin than alone. The weak auxin activity of NPA was confirmed. Transport experiments showed that NPA was the most inhibitory compound tested, followed by TIBA. Other compounds tested were at least 300 times less inhibitory to IAA transport. The best growth promoters were the least inhibitory to transport, and the most effective transport inhibitors were at best poor auxins. It is suggested that the weak auxin and auxin synergistic activity of TIBA (and perhaps 2,3-dichlorobenzoic acid) in extension growth tests arises from its inhibition of transport of endogenous or added auxin out of the sections, rather than from its intrinsic auxin activity. Chemically induced apolar callus growth on vascularized tobacco stem explants can arise from inhibition of native auxin transport, apolar growth stimulation by auxinic action of the test compound, or both.

Journal Article↗
PubMedDate not supplied

Child health education for the foreign-born parent.

Providing child health education for the foreign-born parent presents unique concerns related to language and culture. An innovative approach in a transcultural format used a presentation of basic child health information in English, with translators as facilitators. Foreign-born parents who need partial or complete language interpretation have ready access to translation support. The parents offer questions, comments, suggestions and evaluate the presentation through the translator. Each presentation can accommodate more than one language, since participants are grouped with the appropriate translator. The presentation is done in English and paced to allow for translation to be completed as material is offered. This type of presentation allows discussion of child health in a forum apart from the pediatric care setting. Because the presentation is the only focus, parents do not have the additional concern of immediate care of the child added to communication issues. Vocabulary relative to health care is developed from English into the parents' primary language, with the support of the translator. The pediatric nurse presenter has an opportunity to review health care practices that parents prefer, as well as interpret safety and efficacy.

Adult↗
PubMedDate not supplied

Degree of burn, location of burn, and length of hospital stay as predictors of psychosocial status and physical functioning.

The purpose of this study was to identify predictors of psychologic and physical functioning of the victim with burn injuries from initial hospitalization to discharge. Thirty-one patients admitted to a burn center participated in the study and completed the Burn-Specific Health Scale. Most patients were men between 17 and 45 years of age. Length of stay in the hospital was bimodal, i.e., although about half stayed in the hospital for less than 15 days, about one fifth were hospitalized for more than 28 days. The study hypothesized that degree of burn, location of burn, and length of hospital stay would be associated with psychologic and physical functioning at the first-alert stage (stage of first orientation after burn injury) and the predischarge stage (immediately before discharge from the hospital). At the predischarge stage, the degree of the burn strongly predicted the patient's functioning. Patients with first-degree burns reported lower physical and psychologic functioning on every area of the Burn-Specific Health Scale. Conversely, at the first-alert stage, patients with third-degree burns reported higher psychologic functioning in certain areas (mental and social domains). Having a second-degree burn was not associated with reported psychologic or physical functioning. If the burn involved either the patient's hand or head, the location of the burn predicted certain areas of physical functioning at the first-alert and predischarge stage. Length of hospital stay predicted physical functioning; patients who stayed longer in the hospital reported lower mobility and hand function.

Activities of Daily Living↗
PubMedDate not supplied

Burn wound itch control using H1 and H2 antagonists.

This study investigated the use of a combination of H1 and H2 antagonists and topical medications to control burn wound itch. Graeco-Latin square assignment provided an oral combination of 1) cetirizine and cimetidine or 2) diphenhydramine and placebo in four divided doses. The study protocol lasted 16 days divided into 4-day intervals, scoring itch before the initial dose of medication and at 1-hour, 6-hour, and 12-hour intervals after the first medication. A significant difference between mean itch scores across the four times was observed (Wilks' Lambda F = 26.52, df = 3, P <.0005). A three-way nested repeated measures interaction effect (Wilks' Lambda F = 9.85, df = 9, P <.0005) was observed representing a significantly different pattern on days 1 to 4 of the study compared with the remaining days. Controlling for the effect of topical medications, the cetirizine/cimetidine combination demonstrated a dramatic improvement at 1 and 6 hours, and a moderate improvement at 12 hours after initial medication for the day when compared with the diphenhydramine/placebo combination.

Administration, Cutaneous↗
PubMedDate not supplied

Gall-bladder and sphincter of Oddi response to cholecystokinin in the Australian possum.

The effects of cholecystokinin octapeptide (CCK-OP) on the gall-bladder (GB) and sphincter of Oddi (SO) of the Australian brush tailed possum were examined in 45 anaesthetized animals. CCK-OP (20-640 ng/kg) consistently caused the GB to contract in a dose-dependent manner (Kruskal Wallis P less than 0.05). In 20 animals, the same dose range of CCK-OP produced an excitatory response in the SO, increasing the SO motility index (MI = frequency of contractions x mean peak amplitude) dose-dependently (Kruskal Wallis P less than 0.05). In five animals, an inhibitory response, that is, a decrease in MI, was recorded, with 640 ng/kg of CCK-OP producing a 50% decrease in MI. In the remaining 20 animals, variable responses of both excitation and inhibition were elicited within the same animal. The action of CCK-OP on the SO and GB was not modified by atropine, phentolamine or propranolol. Tetrodotoxin (TTX) reversed the inhibitory responses of the SO to CCK-OP such that responses were excitatory (sign test P less than 0.05). TTX did not alter the response of the GB to CCK-OP. It is concluded that CCK-OP acts directly on smooth muscle receptors of the GB. In the SO, its action is mediated via non-cholinergic, non-noradrenergic inhibitory neurons and also by a direct excitatory action on the smooth muscle of the SO.

Animals↗
PubMedDate not supplied

How safe is endoscopic sphincter of Oddi manometry?

The safety of endoscopic manometry of the sphincter of Oddi was evaluated in a prospective survey of 158 consecutive procedures in 126 patients with either unexplained pain after cholecystectomy or idiopathic recurrent pancreatitis. The only complication was that of pancreatitis which was defined as the development of abdominal pain in association with a plasma amylase above the reference range. This occurred in 13 patients (8%) and was more frequent (P = 0.001) when the indication for the procedure was idiopathic recurrent pancreatitis (29%) than unexplained pain (6%). Pancreatitis was also more frequent (P = 0.02) in patients with abnormal manometry (14%) than in those with normal manometry (3%) and occurred at highest frequency (50%) in a subgroup of patients with idiopathic recurrent pancreatitis and sphincter stenosis (high sphincter basal pressure). All episodes of pancreatitis were mild with a median increase in hospital stay of 2 days; no patients died. The risk of pancreatitis after endoscopic manometry is relatively low but increases in patients with abnormal sphincter manometry, particularly those with idiopathic recurrent pancreatitis.

Abdominal Pain↗
PubMedDate not supplied

Hypertensive putaminal hemorrhage presenting with hemichorea.

A progressive motor deficit primarily manifested by hemichorea developed in a 42-year-old hypertensive man. CT scan demonstrated contralateral putaminal hemorrhage. The patient's course was benign. Previous cases of acute hemichorea familiar to use and documented by CT scans have involved nonhemorrhagic lesions of either the putamen or caudate.

Acute Disease↗
PubMedDate not supplied

Evaluation of two rapid methods for the detection of herpes simplex virus antigen in patient specimens.

An indirect immunofluorescent antibody procedure (IFA) for the detection and typing of herpes simplex virus (HSV) and an enzyme-linked immunosorbent assay (ELISA) procedure were compared with conventional viral culture. Specimens for culture and ELISA were inoculated into serum free viral transport medium (VTM) and, for IFA, onto slides provided in the kit. Tissue cultures (MRC-5 and primary rabbit kidney) were inoculated and examined daily for cytopathogenic effect (CPE). The remaining VTM was frozen at -70 degrees C until tested by the ELISA system. Slides for IFA were stained with HSV common and HSV-2 specific monoclonal antibodies. Of 155 specimens, 47 (30 percent) were unsatisfactory for the IFA test owing to an inadequate number of epithelial cells on the slides. Of 108 adequate specimens, 45 were culture positive; 39 were positive by the IFA test with a sensitivity of 87 percent and a specificity of 90 percent. Of the 39 positives, 29 (75 percent) were correctly classified as type 1 or type 2, six (15 percent) were typed incorrectly, and four (10 percent) were inadequate for typing by the IFA test. All 155 specimens were suitable for testing by the ELISA procedure. Of 55 specimens positive by culture, only 25 (sensitivity 45 percent) were positive by ELISA. However, the specificity was 100 percent. After incubation of two, three, and six days, the tissue cultures detected 71 percent, 89 percent, and 100 percent of the positives, respectively.

Antigens, Viral↗