Regulation of gastric emptying in humans by cholecystokinin.

In the present study we used a bioassay system for measuring plasma cholecystokinin (CCK) to evaluate whether CCK has a physiologic role in regulating gastric emptying in humans. Plasma CCK levels and gastric emptying after ingestion of a mixed liquid meal were determined in five normal male volunteers. Fasting CCK levels averaged 0.8 +/- 0.1 pM and increased to 6.5 +/- 1.0 pM within 10 min of drinking the mixed meal. CCK levels remained elevated for up to 90 min. Gastric emptying after a meal was slow; at the end of the 90 min 68% of the original volume remained in the stomach. The rate of gastric emptying of water was then measured in the same individuals with a simultaneous infusion of either saline, or one of two doses of CCK (12 pmol/kg per h and 24 pmol/kg per h). With the saline infusion, plasma CCK levels did not increase above basal and gastric contents emptied rapidly. At the end of 90 min only 7% of the original volume remained in the stomach. The lower dose of CCK resulted in a plasma level of 3.4 pM which both reproduced the average postprandial plasma level and caused a significant delay in gastric emptying. The higher dose of CCK achieved plasma levels of 8 pM and resulted in a delay in gastric emptying that was similar to that seen with the mixed meal. Since exogenous CCK at concentrations which occur postprandially delays gastric emptying, we conclude that CCK is a physiologic regulator of gastric emptying.     

Are there unknown mineralocorticoids in low-renin essential hypertension?

The blood pressure elevation of primary aldosteronism is caused by excessive production of the known mineralocorticoid, aldosterone. The blood pressure elevation of low-renin essential hypertension may also be caused by mineralocorticoid excess, but which which mineralocorticoid is responsible is uncertain. Normal levels of aldosterone, found in this disorder despite suppressed plasma renin, and the presence of an unknown mineralocorticoid have been hypothesized to explain low-renin essential hypertension. We contrasted the blood pressure responses and changes in aldosterone seen in patients with low-renin essential hypertension and primary aldosteronism during treatment with two adrenal enzyme inhibitors. The results demonstrate the similarity between decrease in blood pressure and in aldosterone during early adrenal inhibition in both primary aldosteronism and in low-renin essential hypertension. During treatment with a distal adrenal blocker, patients with primary aldosteronism demonstrated decreases in both aldosterone and blood pressure, whereas patients with low-renin essential hypertension showed a decrease in aldosterone without significant change in blood pressure. This suggested that aldosterone was not the major mineralocorticoid responsible for low-renin essential hypertension. Unknown mineralocorticoid excretion decreased (along with blood pressure) during early inhibition but failed to decrease (along with blood pressure) during late inhibition at a time when aldosterone excretion decreased. This suggests that unknown mineralocorticoids play significant roles in the blood pressure elevation of low-renin essential hypertension.     

Evaluation of the off-label usage of rituximab in a large teaching hospital in New South Wales

A retrospective review of patients receiving rituximab off label in a large teaching hospital was conducted between July 2002 and January 2006. The indication, dosing regimen, efficacy and cost of rituximab were evaluated. Rituximab was prescribed for three clinical indications; acute organ transplant rejection, post-transplant lymphoproliferative disease and autoimmune disease. On average, 600 mg of rituximab was prescribed weekly for 4 weeks, costing the hospital $108,739.37. We suggest an initial approval for a limited number of doses with subsequent approval dependent on improvement in predefined clinical or biochemical end-points. Furthermore, we suggest an Australia-wide central database be established to enable delineation of the optimal dosing schedule, as well as monitoring of clinical outcome.     

The determinants of successful in-hospital rehabilitation in people aged 90 years and older

BACKGROUND/OBJECTIVES: The very elderly constitute a subgroup of elderly who may respond differently than the younger elderly to medical intervention. This possibility has not previously been investigated. Our study investigates whether successful rehabilitation of the very elderly is possible within the current processes of care and also whether factors that help predict successful rehabilitation in all age elderly are applicable to the oldest old. METHODS: A retrospective case note analysis of all very elderly people (>or=90 years old) treated within in-patient elderly person rehabilitation facilities at the Northern General Hospital, Sheffield. Potential predictive factors analysed: Barthel index, main presenting illness, number of co-morbid conditions, number of regular prescribed medications, abbreviated mental test score, prior formal social services input, previous hospital admission within 1 year and serum albumin (g/l). Outcome measures reflecting success of rehabilitation: duration of rehabilitation (days), discharge destination to the same ('good outcome') or increased ('poor outcome') level of social and/or nursing care, readmission to hospital within 30 days of discharge and death during rehabilitation or within 120 days of discharge. RESULTS: Of 230 nonagenarians admitted to inpatient elderly rehabilitation 47% required no increase in social support following their admission and 76% of those admitted from their own home were able to return there. Barthel index and the number of co-morbid conditions were the most influential predictors of success, with Barthel index predicting length of stay (p < 0.001), discharge destination (p < 0.001) and in-hospital mortality (p < 0.01) and co-morbidity predicting readmission to hospital (p = 0.05), in-hospital mortality (p = 0.04) and survival (p = 0.05). On multi-variate analysis all other predictive factors analysed, except for presenting illness, were associated with at least one outcome measure (p < 0.05). CONCLUSION: Successful inpatient rehabilitation of the very elderly is possible. Factors that predict the success of rehabilitation of nonagenarians are similar to those associated with success in the younger elderly. The factors that most broadly predict success are Barthel index and the number of co-morbid conditions identified at admission to rehabilitation. Main presenting illness did not emerge as a predictor within this group.     

Reduced event-related low frequency EEG activity in schizophrenia during an auditory oddball task

This study examines EEG low frequency characteristics which have been linked to specific cognitive functions such as stimulus encoding and attention during an auditory oddball task in schizophrenia patients and healthy controls. EEG data was recorded from 17 young schizophrenia patients in a stable phase of their illness and 17 healthy controls performing an auditory oddball task. Evoked and induced delta and theta activity, N100, P300 amplitude were computed. Between 200–500 ms after a stimulus was presented, patients displayed significantly reduced P300, less evoked and induced delta and theta activity than controls. We conclude that the well known finding of P300 reduction in schizophrenia can be linked to reductions in delta and theta activity, which are a manifestation of impaired stimulus evaluation, memory retrieval, and a lack of sustained attention.     

Comparison of time use, role participation and life satisfaction of older people after stroke with a sample without stroke

Background/aims:  This study investigated the time use, role participation and life satisfaction of older Australians (aged 65 years and older) who were 1–3 years post-stroke and living in the community. The results of this study were compared with a published study on the time use, role participation and life satisfaction of older Australians who had not experienced stroke.
Methods:  Twenty-three participants with stroke (mean age 74.2 years, 69.6% men) were interviewed using measures of time use, role participation and life satisfaction.
Results:  Participants with stroke spent most of their time in sleep (7.2 h/day), solitary leisure (7.0 h/day), social leisure (3.0 h/day), and basic activities of daily living (2.9 h/day). Compared to the sample without stroke, participants with stroke spent significantly less time in sleep, instrumental activities of daily living, and volunteer work, and significantly more time at home, with others, and engaged in solitary leisure. Similar to the sample without stroke, the most common roles for participants with stroke were family member, friend, and home maintainer. Participants with stroke engaged in fewer roles than participants without stroke. Unlike the sample without stroke, role loss was not correlated with life satisfaction for participants with stroke; however, having more roles was correlated with greater life satisfaction.
Conclusion:  Experiencing a stroke can affect the configuration of older people's time use and reduce their role participation. Facilitation of older people's role participation after stroke may enhance their life satisfaction.     

Error-related negativity and correct response negativity in schizophrenia.

OBJECTIVES: To examine error-related negativity (ERN) and correct response negativity (CRN) in schizophrenia in light of two previous conflicting reports, and to determine their relation to disorganization, psychomotor poverty and reality distortion. METHODS: Event-related potentials were recorded from 21 schizophrenic and 21 control participants who performed a simple go/no-go task. Response-locked potentials were computed for errors of commission and for correct-hits. Scores for reality distortion syndrome, psychomotor poverty syndrome and disorganization syndrome were determined for each schizophrenic participant using the Signs and Symptoms of Psychotic Illness (SSPI) scale. RESULTS: ERN produced during error trials and CRN produced during correct trials were significantly larger in the control participant group than in the schizophrenic participant group. In the schizophrenic patients, ERN amplitude was negatively correlated with psychomotor poverty syndrome score and CRN amplitude was negatively correlated with disorganization syndrome score. CONCLUSIONS: Decreased ERN and CRN in the schizophrenic participant group suggests abnormal internal behavior monitoring in schizophrenic patients. Patients with high disorganization symptoms may employ an abnormal strategy for comparing actual response outcome with desired response outcome, while patients with psychomotor poverty may be less emotionally responsive to errors.     

Acculturation and drug use among dually diagnosed Hispanic adolescents

With drug abuse among Hispanic youth on the rise, examining cultural factors such as acculturation may provide insight into understanding and addressing this problem. This study examined the relationship between acculturation and severity of drug use among a sample of severely impaired Hispanic adolescents referred for residential substance abuse treatment. As recent studies with clinical samples have found, it was hypothesized that lower levels of acculturation would be associated with higher levels of substance use. Results indicated that youth born outside the United States reported greater frequency of drug use at intake into treatment than those born in the United States, supporting the hypothesis.