Do oats belong in a gluten-free diet?

Celiac disease is an intolerance to protein fractions in wheat, rye, barley, and possibly oats. When these grains are consumed by a person with celiac disease, they damage the mucosa of the small intestine, which eventually leads to malabsorption of nutrients. Patients are therefore advised to remove these grains from their diet, with lifelong adherence generally suggested. Although many dietitians and physicians consider this dietary prescription to be standard protocol, it is actually quite controversial. Whether oats can safely be consumed by persons with celiac disease has been debated since the gluten-free diet was first advocated more than 40 years ago. Historically, there have been several reasons for this debate, including the difficulty in identifying the precise amino acid sequence in gliadin that is responsible for toxicity; the differences in cereal chemistry between wheat and oats; and the lack of well-designed studies to assess the toxicity of oats. A growing body of evidence now suggests that moderate amounts of oats may be safely consumed by most adults with celiac disease. If further research continues to find no adverse effects from oat consumption, a consensus may emerge on the place of oats in the gluten-free diet. In the meantime, individual dietary prescriptions, routinely assessed for appropriateness using histologic and/or serologic studies, may be warranted to prevent unnecessary dietary restrictiveness and undesirable medical complications.

Isolation and identification of major urinary metabolites of rifabutin in rats and humans

The antimycobacterial drug rifabutin is extensively metabolized in humans and laboratory animals. About 40% of the dose is excreted in urine as unchanged drug, and lipophilic (extractable with 1-chlorobutane) and polar metabolites. Polar metabolites accounted for 59.1 +/- 2.5% and 88.8 +/- 4.4% of radioactivity in urine collected over 96 hr after intravenous administration of 25 and 1 mg/kg of [14C]rifabutin to Sprague-Dawley rats, respectively. After 48 hr, all urinary radioactivity consisted of polar metabolites. The most abundant polar metabolite, identified by electrospray ionization-MS, collision-induced dissociation-MS, and comparison of HPLC retention times with the synthetic standard, was N-isobutyl-4-hydroxy-piperidine. Lipophilic metabolites accounted for <20% of urinary radioactivity. Major lipophilic metabolites, 25-O-deacetyl-rifabutin, 27-O-demethyl-rifabutin, 31-hydroxy-rifabutin, 32-hydroxy-rifabutin, and 20-hydroxy-rifabutin were isolated from both human and rat urine by HPLC and identified by electrospray ionization-MS, collision-induced dissociation-MS, and NMR spectrometry. In addition, two metabolites formed by the oxidation of the N-isobutyl-piperidyl group of rifabutin were found in the urine of rats, but not humans.

Cross-reactions of reagents from streptococcal grouping kits with Streptococcus porcinus

Streptococcus porcinus is usually associated with swine. Because we have received several isolates from human sources that had cross-reacted with commercial group B streptococcal reagents, we examined several commercial kits to determine the extent of this cross-reaction. Fifteen reference and 15 clinical strains of S. porcinus were tested for cross-reactions with group B streptococcal reagents from 12 different commercial kits. Cross-reactions were detected with all group B reagents, but the number of cross-reactions varied with each kit. We recommend that manufacturers of reagents designed to identify group B streptococci by serologic methods test their reagents for cross-reactions with selected S. porcinus cultures or antigens.

Concomitant intraarterial cisplatin, intravenous 5-flourouracil, and split-course radiation therapy for locally advanced unresectable pancreatic adenocarcinoma: a phase II study of the Puget Sound Oncology Consortium (PSOC-703)

A Gastrointestinal Tumor Study Group (GITSG) protocol showed a survival benefit for patients with locally advanced unresectable pancreatic adenocarcinoma when treated with split-course radiation therapy and bolus intravenous (i.v.) 5-fluorouracil (5-FU) as compared with survival achieved with radiation alone. In an attempt to improve these results, a phase II trial using intraarterial (i.a.) cisplatin, systemic-infusional 5-FU, and concomitant split-course radiation therapy was conducted. Sixteen previously untreated patients with unresectable pancreatic adenocarcinoma (5 with American Joint Committee on Cancer [AJCC] stage I-II, 11 with stage III) disease were treated with i.a. cisplatin 100 mg/m2 by selective celiac arteriography followed by i.v. infusional 5-FU 1,000 mg/m2/day for 4 days, and concomitant split-course external beam photon radiation therapy at 2.0 Gy for 10 days in a 12-day period. After a planned 14-day interval, the identical chemoradiation treatment was repeated; finally, after a second 2-week interval, a third cycle of chemotherapy with a final 10 Gy radiation was administered. All 16 patients were evaluable for response; there were two partial responses (PR: 12%) and five minor responses (31%). Median follow-up period was 77 months. Median time to progression was 6 months (range 1-12 months), and median survival was 9 months (range 4-94 months). Nausea/vomiting was the major toxicity. There were no treatment-related fatalities. This regimen of concomitant i.a. cisplatin, i.v. infusional 5-FU, and split-course external beam photon radiation is well tolerated but has minimal activity in the treatment of locally advanced unresectable pancreatic adenocarcinoma. Future combined-modality protocols for this disease should explore alternative chemoradiation schemes.

Transfer of social attributions in stimulus equivalence classes by preschool children

The transfer of social attributions within stimulus-equivalence classes comprised of photographs of children was examined. Five children (mean age: 4 yr., 2 mo.) were taught conditional discriminations sufficient for the emergence of two 3-member equivalence classes (A1-B1-C1 and A2-B2-C2). Social attributions were established by using two photographs to identify fictional children who could facilitate (B1) or prevent (B2) the participant's reinforcement on a computer game. Transfer of attribution was assessed by asking the participants questions regarding predicted social behaviors by children in all six photographs. One set of questions pertained explicitly to the response-options of the computer game; a second set referred to other prosocial and antisocial behaviors. Three children chose photographs in response to questions consistent with their experience with members B1 and B2 of the shared equivalence class when the questions pertained to the computer game. One subject also selected photographs in response to questions about predicted prosocial and antisocial behavior which reflected her experience with the B1 and B2 photographs.

Elevated plasma gamma-aminobutyric acid (GABA) levels in individuals with either Prader-Willi syndrome or Angelman syndrome

Plasma gamma-aminobutyric acid (GABA) levels were measured in 14 subjects with Prader-Willi syndrome, 9 subjects with Angelman syndrome, and matched control subjects. Mean levels in both patient groups were 2 to 3 times higher than in nonretarded moderately obese or retarded nonobese control subjects. Levels in each patient group differed significantly from both control groups. Neither the two patient groups nor the two control groups differed. GABA levels seemed unrelated to genetic status (chromosome 15 deletion or disomy). These preliminary findings of elevated plasma GABA levels possibly represent a compensatory increase in presynaptic GABA release in response to hyposensitivity of a subset of GABA receptors and could produce increased postsynaptic activation of other normal GABA receptor subtypes, resulting in complex alterations of GABAergic function throughout the brain.

Food- and nonfood-related differential outcomes in equivalence learning by adults with Prader-Willi syndrome

Adults with Prader-Willi syndrome learned the conditional relations necessary for the formation of two equivalence classes under four conditions: (a) nondifferential, nonedible outcomes; (b) nondifferential, edible outcomes; (c) differential, nonedible outcomes; and (d) differential, edible outcomes. Tests for transitive relations revealed superior performance when the two differential outcomes procedures, in which a distinct reinforcer was associated with each stimulus set, were used during teaching. Performance on test trials following nondifferential outcomes training was better when edible outcomes were used during teaching for 4 of the 5 participants. An enhancement of performance on the derived relations separated by two or three nodal stimuli was seen when a differential outcomes procedure was used to teach the baseline conditional relations.

In vivo disposition and metabolism by liver and enterocyte microsomes of the antitubercular drug rifabutin in rats

The in vivo disposition and in vitro metabolism of rifabutin, a new spiropiperidylrifamycin, were studied in rats and in microsomes from rat liver and enterocytes, respectively. After i.v. doses of 1,5, 10 and 25 mg/kg the systemic clearance was 0.7 to 1.0 liters/hr/kg; the volume of distribution was 4.4 liters/kg for the 1 mg/kg dose and 7.4 to 7.7 liters/kg for the 5 to 25 mg/kg doses, and the half-life ranged from 4.4 to 9.1 hr. Urinary and fecal excretion over 0 to 96 hr after i.v. administration of 25 mg/kg [14C]rifabutin accounted for 40.1 and 52.2% of the dose, respectively. Exteriorization of the bile duct showed that approximately 24% of the dose was eliminated in bile, > or = 98% as metabolites. Bioavailability after oral administration of 25 and 1 mg/kg rifabutin was > 90% and 44%, respectively, suggesting significant first-pass metabolism of the lower dose. Concentrations of rifabutin in gastric juice were 10 to 17 times higher than in blood, indicating extensive secretion into the stomach. Experiments with the isolated small intestinal loop demonstrated direct exsorption of the drug into the lumen. The rate of rifabutin metabolism by enterocyte microsomes was > 10 times higher than that by liver microsomes, i.e., 84 and 8 pmol/min/mg protein, respectively. Biotransformation of rifabutin in vivo and in vitro was markedly induced by dexamethasone and inhibited by erythromycin, suggesting that CYP3A is involved in the metabolism of rifabutin. Several metabolites, including 20-OH-rifabutin and 27-O-demethyl-rifabutin, isolated from urine and microsomes were identified by mass spectrometry and nuclear magnetic resonance spectroscopy.

Architectural features and perceptions of community residences for people with mental retardation

Architects, group home administrators, people with mental retardation, family members of people with mental retardation, and college undergraduates substantially agreed regarding the rated homelikeness of slides of interiors of 20 community residences for people with mental retardation ranging from institutional to homey, mean r = .87. Clusters of physical features identified using an architectural inventory were found to be associated with homelikeness ratings. Adjectives applied to rooms with these features were determined using a Q-sort method. Two factors were identified from Q-sort correlations: Homelikeness-Institutionality and Spatial Organization as well as a third variable, privacy.

Interdependence of architectural features and program variables in community residences for people with mental retardation

In an earlier study, we found that architects, group home administrators, people with mental retardation, family members of people with mental retardation, and college undergraduates rated the homelikeness of slides of community residences for people with mental retardation similarly. In addition, clusters of physical features were identified that were specifically associated with homelikeness ratings. In the present study, behavior of residents with mental retardation living in those residences was assessed using the Aberrant Behavior Checklist and direct behavioral observations. After statistically controlling for confounding variables, we found that adaptive and maladaptive behavior covaried with homelikeness ratings. In addition, we were able to identify associations between specific architectural features of residential settings and the behavior of residents living in those settings.

31P magnetic resonance spectroscopy studies in schizophrenia

Phospholipid metabolism abnormalities have been suggested by a number of postmortem brain and red blood cell studies in schizophrenia. 31P magnetic resonance spectroscopy enables the examination of phospholipid metabolism in living patients. These in vivo studies have demonstrated that schizophrenic patients have lower prefrontal levels of phosphomonoesters and higher levels of phosphodiesters compared to matched controls. Patients with psychotic depression also seem to show lower levels of phosphomonoesters compared to controls. This suggests that membrane phospholipid differences may not be specific to schizophrenia. Preliminary 31P magnetic resonance spectroscopy studies at high field strength on postmortem temporal lobe samples show no differences between treated schizophrenic patients and controls for phosphoethanolamine and phosphocholine which are the main constituents of the phosphomonoester peak. Further studies are underway in the prefrontal region. While 31P magnetic resonance spectroscopy studies have demonstrated membrane phospholipid abnormalities in schizophrenia, it is not clear whether these findings are specific to schizophrenia or part of a generalized membrane phospholipid abnormality.

Sequencing emm-specific PCR products for routine and accurate typing of group A streptococci

Rapid sequence analysis of specific PCR products was used to accurately deduce emm types corresponding to the majority of the known group A streptococcal (GAS) M serotypes. The study involved 95 M type reference GAS strains and a survey of 74 recent clinical isolates. A high percentage of agreement between M type serology and the previously published 5' sequences of the emm genes of M type reference strains was noted. The 5' sequences for six established M protein genes--the emm-32, emm-34, emm-38, emm-40, emm-42, and emm-71 genes--were determined to supplement the existing emm sequence database. Rapid sequence analysis differentiated serologically M-nontypeable strains and was used to establish the probable.

Functional significance of the early component of the human blink reflex

The relationship between the size of the first electromyographic (EMG) component of the cutaneous blink reflex (R1) and onset of eyelid closure in human adults was determined in 4 experiments in which R1 size was varied by different means: change in stimulus intensity, paired stimulation, and warning. Two-phase lid movements were frequently seen, with an early small movement followed by a large rapid movement. All experiments showed that larger R1s were associated with shorter latencies of both movements. This covariation was general across participants and was independent of shifts in the excitability of the blink reflex pathways indexed by R1 latency, R2 latency, and R2 area (R2 is the more prolonged, later EMG component). The results indicate that R1 acts first to evoke an early lid movement and second to facilitate eyelid closure by the later R2 burst. Identification of this second behavioral function for R1 aids the interpretation of other findings and encourages its use as a model system.

Functional significance of the early component of the human blink reflex

The relationship between the size of the first electromyographic (EMG) component of the cutaneous blink reflex (R1) and onset of eyelid closure in human adults was determined in 4 experiments in which R1 size was varied by different means: change in stimulus intensity, paired stimulation, and warning. Two-phase lid movements were frequently seen, with an early small movement followed by a large rapid movement. All experiments showed that larger R1s were associated with shorter latencies of both movements. This covariation was general across participants and was independent of shifts in the excitability of the blink reflex pathways indexed by R1 latency, R2 latency, and R2 area (R2 is the more prolonged, later EMG component). The results indicate that R1 acts first to evoke an early lid movement and second to facilitate eyelid closure by the later R2 burst. Identification of this second behavioral function for R1 aids the interpretation of other findings and encourages its use as a model system.

The meaning of alcohol to traditional Muscogee Creek Indians

The purpose of this study was to learn the meaning of alcohol to the traditional Muscogee Creek Indians of eastern Oklahoma. Using Leininger's theory of culture care diversity and universality as the theoretical base, the authors conducted interviews of 24 traditional people to elicit both emic and etic meanings of alcohol. The conceptualization of alcohol as a dichotomy of power to do both good and evil emerged as the central theme. Other meanings of alcohol were explicated in relation to five social structure dimensions. The findings suggest culturally competent nursing implications for preserving, accommodating, and repatterning the meaning of alcohol.

Causes of alcoholism: a qualitative study of traditional Muscogee (Creek) Indians

Traditional Native American people are experiencing serious health, economic, and social problems resulting from alcoholism. Native Americans maintain a worldview of health and illness that conflicts with the dominant culture's approach to treatment. The purposes of this study were to describe the health beliefs of traditional Muscogee (Creek) Indians concerning the causes of illness and learn how these beliefs relate to alcoholism. The researchers conducted in-depth interviews of 55 traditional Muscogee (Creek) participants to learn traditional beliefs about illness and alcoholism. Data were analyzed using content analysis. Results indicate that both illness and alcoholism are perceived as having natural and unnatural (supernatural) causes. A challenge facing nurses is how to provide culturally sensitive care when clients' and nurses' beliefs about the cause of alcoholism may be in conflict. The authors discuss preservation, accommodation, and repatterning of health care beliefs as a basis for planning culturally sensitive nursing care.

Cytochromes CYP1A1 and CYP1B1 in the rat mammary gland: cell-specific expression and regulation by polycyclic aromatic hydrocarbons and hormones

Cultured rat mammary cells express both CYP1A1 and CYP1B1 in response to polycyclic aromatic hydrocarbons (PAH) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in a cell type-specific manner. The expression of each P450 was determined functionally (regioselective PAH metabolism), as apoprotein (immunoblots) and as mRNA (Northern hybridization). The epithelial rat mammary cells (RMEC) expressed CYP1A1, however only after PAH or TCDD treatment. CYP1B1 protein was scarcely detected in these induced RMEC but was surprisingly active as a participant in 7,12-dimethylbenz[a]anthracene (DMBA) metabolism shown through selective antibody inhibition (40% of total activity). CYP1B1 was selectively expressed in the stromal fibroblast population of rat mammary cells to the exclusion of CYP1A1. In the rat mammary fibroblasts (RMF), CYP1B1 protein and associated activity were each present at low levels constitutively and were highly induced by benz[a]anthracene (BA) to a greater extent than by TCDD (12- versus 6-fold). However, BA (10 microM) and TCDD (10 nM) stimulated the 5.2-kb CYP1B1-specific mRNA equally. These increases are consistent with the involvement of the aryl hydrocarbon (Ah) receptor in the transcription of the CYP1B1 gene and with the additional stabilization of CYP1B1 protein by BA, previously observed in embryo fibroblasts. Exactly this regulation of CYP1B1-dependent activity was seen in RMEC suggesting that this arises from exceptionally active CYP1B1 in a small proportion (5%) of residual RMF. The constitutive expression and PAH inducibility of CYP1B1 and CYP1A1 proteins in RMF and RMEC, respectively, were each substantially decreased (approximately 75%) by a hormonal mixture (17 beta-estradiol (0.2 microM) progesterone (1.5 microM) cortisol (1.5 microM) and prolactin (5 micrograms/ml)). Progesterone and cortisol, added singly to RMF suppressed CYP1B1 protein expression (approximately 80%) in both untreated and BA-induced cells, while cortisol also suppressed the 5.2-kb CYP1B1 mRNA. In contrast, 17 beta-estradiol stimulated constitutive expression of CYP1B1 protein (50-75%) and mRNA level (2- to 3-fold), but did not affect CYP1B1 expression in BA-treated RMF. The expression of CYP1A1 and CYP1B1 is therefore highly cell specific even though each is regulated through the Ah receptor. Each P450 exhibits a surprisingly similar pattern of hormonal regulation even though expressed in different cell types.

Effects of genetic background on tumorigenesis in p53-deficient mice

Mice with disrupted germline p53 alleles have been engineered by us and others and have been shown to have enhanced susceptibility to spontaneous tumors of various types. We monitored a large number of p53-deficient mice (p53+/- and p53-/-) and their wild-type littermates (p53+/+) of two different genetic backgrounds (129/Sv and mixed C57BL/6 x 129/Sv) up to 2 yr of age. p53+/- and p53-/- 129/Sv mice show accelerated tumorigenesis rates compared with their p53-deficient counterparts of mixed C57BL/6 x 129/Sv genetic background. The tumor spectra of the two strains of mice are similar except that almost half of 129/Sv p53-/- males develop malignant teratomas, whereas these tumors are rarely observed in C57BL/6 x 129/Sv mice and never in 129/Sv p53+/- males. In the study reported here, we further characterized the lymphomas that arose in the p53-nullizygous mice and found that over three-quarters of the lymphomas were of thymic origin and contained primarily immature (CD4+/CD8+) T-cells, whereas the remainder originated in the spleen and peripheral lymph nodes and were of B-cell type. The high incidence of early-onset lymphomas in the nullizygous mice makes these animals a good lymphoma model, whereas the heterozygous mice may be a useful model for Li-Fraumeni syndrome, a human inherited cancer predisposition.

Effects of neuropeptide Y, insulin, 2-deoxyglucose, and food deprivation on food-motivated behavior

The current study demonstrates the ability of neuropeptide Y (NPY) to increase break points under a progressive ratio 1 (PR1) reinforcement schedule. An initial response resulted in delivery of a food reinforcer (45 mg pellet) under the PR1, and an additional response was required for each successive reinforcer. The break point, the number of responses emitted to obtain the last reinforcer, is considered a measure of reinforcing efficacy or motivational strength of the food reinforcer. NPY (0.3-10 micrograms) significantly increased break point to levels comparable to those produced by 36-48 h of food deprivation. Although insulin (3-8 U/kg) and 2-deoxyglucose (150-250 mg/kg) also increased food intake, neither increased break points to levels produced by NPY or food deprivation. These data suggest that NPY may change the value of food in ways that cannot be accounted for by changes in insulin, glucose levels or intracellular glucoprivation. These results emphasize that simply measuring the amount of freely available food eaten is not a fully adequate measure of the strength of the feeding behavior.

Defining and treating challenging behaviour

Behavioural disorders present extreme problems for clients and careers. In this article, the authors discuss a definition of challenging behaviour. Types of behaviour classified as 'challenging' and possible responses to them, are also considered. Some of the points are illustrated with short case studies.