The effects of hyperbaric oxygen therapy on oxidative stress,inflammation, and symptoms in children with autism: an open-label pilot study

Background  

Recently, hyperbaric oxygen therapy (HBOT) has increased in popularity as a treatment for autism. Numerous studies document oxidative stress and inflammation in individuals with autism; both of these conditions have demonstrated improvement with HBOT, along with enhancement of neurological function and cognitive performance. In this study, children with autism were treated with HBOT at atmospheric pressures and oxygen concentrations in current use for this condition. Changes in markers of oxidative stress and inflammation were measured. The children were evaluated to determine clinical effects and safety.     

Analysis of the conducting airway system in the lung: A new method combining morphometry with mathematical modeling for airway classification

Although the lung is structurally complex, it is suitable for morphometric analysis of the structural determinants of lung function in health and disease. Analysis of the organized branching airways has been problematic because of the need to identify and classify airways before structural characteristics of different‐order branches can be determined. Airway casts have been used to identify relationships between branches, measure some structural features, and develop mathematical models that describe simply the relationships between generations. However, cast preparation destroys surrounding tissue, including the airway wall, thus precluding analysis of these structural elements. We describe a new approach using tissue sections which combines the classification of airways into Strahler order (SO) with tissue structural analysis. Lung‐tissue sections are prepared, and outer (OD) and inner (ID) diameters are determined over a wide range of airways. The line equation relating log OD vs. SO is determined using measured values for SO1 (terminal bronchioles) and SO8 (first branch bronchi). Mean ODs can then be calculated for each of the other SO groups, and measurements can be classified. Calculations can be made for the mean number of branches and airway lengths (given the log linear relationship of these factors with SO and morphometrically determined volume densities for airway lumen), and for individual airway resistance and total resistances for each SO. For an example, mean data are presented for airways in the adult sheep (n = 13). The methodology presented allows identification of subtle alterations in airway structures which may be affecting selected orders of airways, with specific implications for changes in lung function. Anat Rec 266:51–57, 2002. © 2002 Wiley‐Liss, Inc.     

S-Adenosylhomocysteine, but not homocysteine, is toxic to yeast lacking cystathionine β-synthase

Elevated plasma homocysteine is associated with a variety of diseases in humans including coronary heart disease, stroke, peripheral vascular disease, and birth defects. However, the mechanism by which plasma homocysteine affects cells is unknown. We have examined the growth of isogenic wild-type and cystathionine beta-synthase (CBS) deficient yeast in response to homocysteine and its immediate metabolic precursor, S-adenosylhomocysteine (SAH). CBS deficient yeast export significantly more homocysteine into the media than wild-type yeast and have elevated internal pools of homocysteine and SAH. We found that 5 mM homocysteine added to the media had very little effect on the growth of wild-type or CBS deficient yeast, although intracellular homocysteine concentrations increased five- to tenfold. In contrast, as little as 25 microM S-adenosylhomocysteine inhibited the growth of CBS deficient yeast, but had no effect on wild-type yeast. Measurements of the intracellular S-adenosylmethionine (SAM) and SAH indicate that CBS deficient yeast contain reduced SAM/SAH ratios relative to wild-type, and this ratio is further reduced by adding SAH to the media. Growth inhibition by SAH in CBS deficient yeast can be totally reversed by addition of SAM to the media, indicating that the ratio and not absolute level is critical for cell growth. These results suggest that CBS plays a key role in the regulation of the SAM/SAH ratio inside cells and that excessive perturbations of this ratio can inhibit growth. We hypothesize that elevated extracellular homocysteine present in humans may reflect an altered intracellular SAM/SAH ratio and that this may be related to disease pathogenesis.     

Factor analysis of bowel symptoms in US and Italian populations

BACKGROUND AND AIMS: Functional gastrointestinal disorders are diagnosed by the presence of a characteristic set of symptoms. Aims of this study were to validate the Rome symptom criteria by factor analysis and to determine whether symptoms cluster in the same way in different cultures. METHODS: One thousand forty-one gastroenterology clinic patients in the US (response rate 53%) and 228 family members accompanying clinic patients in Italy (84%) completed a previously validated symptom questionnaire. Factor analysis identified clusters of symptoms which are highly correlated with each other, and these were compared to the Rome diagnostic criteria. RESULTS: In the US, 13 factors were identified. The irritable bowel factor was composed of three core symptoms corresponding to the Rome II classification system. Two dyspepsia factors were identified which correspond to the ulcer- and motility-like subtypes proposed in the Rome I classification system. All symptoms of constipation formed a single cluster as proposed in the Rome II classification system. Symptom clusters in the US agreed well with symptom clusters identified in Italian subjects. CONCLUSIONS: Empirically derived symptom clusters agree in most respects with the Rome II classification system and support their validity. These symptom clusters are independent of cultural differences in diet and behaviour.     

Project 2000: perceptions of the philosophy and practice of nursing: shifting perceptions—a new practitioner?

This is the first of two papers which address aspects of the findings of a large scale study commissioned by the English National Board which set out to examine the impact of Project 2000 on perceptions of the philosophy and practice of nursing. The findings presented here suggest that there have been fundamental shifts in perceptions of the nature and discipline of nursing. Students and diplomates of the course perceive themselves as knowledgeable doers, with their practice well grounded in theory and research. They value the interpersonal skills teaching and place the patient firmly at the centre of care delivery, viewing the patient holistically and being prepared to be fierce patient advocates where necessary. It is difficult to determine the extent to which these shifts can be attributed to the Project 2000 course, although the Project 2000 approach to education appears to be an important factor.     

The safety of patient-controlled sedation

We have investigated the safety of a previously described method of patient-controlled sedation in 100 healthy patients presenting for elective surgery. The device used 0.33-ml boluses of propofol (10 mg.ml⁻¹) infused over 6 s with no lockout. All patients attempted to put themselves to sleep by pressing a button on the hand-held device. The oxygen saturation, heart rate, sedation score and airway patency were noted every minute. When the patient stopped pressing the button, the anaesthetist took over the handset and continued pressing the button until the patient became unresponsive. The system allowed rapid sedation. Only five patients were still anxious after 2 min. After 3 min, no patient was still anxious and more than 70 patients had slurred speech. When they stopped pressing the button, 11 patients were judged oversedated, of whom two were unresponsive. One patient's oxygen saturation decreased transiently to 84%: no other patient's oxygen saturation decreased below 90%. There were no other significant changes. We conclude that the system studied works well but carries too high a risk of oversedation for unsupervised use.     

Canada must keep single-tier health care, National Forum on Health maintains

As new knowledge and economic constraints affect the delivery of health care services, Canada is embarking on a reassessment of its medicare program. Even before the dialogue gets under way, however, the National Forum on Health that was appointed by the prime minister has already taken one firm stand by declaring that Canada must maintain its single-tier health care system.