Autonomic regulation of postprandial plasma somatostatin, gastrin, and insulin.

To evaluate the neural regulation of postprandial somatostatin release we studied the effect of blockade of (a) alpha-adrenergic and beta-adrenergic and (b) cholinergic receptors on the plasma somatostatin, gastrin and insulin responses to a standard meal in two groups of five fasting healthy male volunteers. Thymoxamine (0.1 mg/kg iv over two minutes then 10 mg/hour for two hours) and propranolol (0.15 mg/kg iv over two minutes, then 0.75 mg/kg/hour for two hours) were started just before eating while atropine (0.04 mg/kg/im) was given at 15 minutes on completion of the meal. There was a prompt and sustained rise in plasma somatostatin after a control meal in all experiments. This rise was arrested by atropine but not altered by either thymoxamine or propranolol. The plasma gastrin response to a meal was moderately enhanced by thymoxamine and markedly enhanced by atropine. Postprandial insulin release was not affected by alpha- or beta-adrenergic blockade but was abolished by atropine. The effect of atropine on the postprandial plasma somatostatin rise might have been mediated through reduction in gastric acidity or delay in gastric emptying. Hence we gave five fasting male volunteers and intraduodenal infusion of fat emulsion (25 calories in 30 minutes) on two occasions both alone and after atropine. Plasma somatostatin rose during the fat infusion alone and this rise was abolished by atropine. These data suggest that (a) cholinergic but not adrenergic mechanisms are important modulators of plasma somatostatin release after orally ingested and intraduodenally infused nutrients (b) atropine abolishes plasma somatostatin release independently of its effects on gastric acidity and motility and (c) are consistent with the hypothesis that atropine potentiates postprandial gastrin release through reduction of somatostatin mediated inhibition.     

Paralysis and unilateral arthritis: is the association established ?

Summary A patient with long-standing upper limb lower motor neurone paresis more recently developed homolateral upper motor neurone hemiplegia. Subsequent primary generalised osteoarthritis spared only the paralysed upper limb. Detailed review of reported cases suggest that the protective effect of paralysis against subsequent development of arthritis is not as clearly established as generally believed.     

Surgical management of synchronous coronary artery disease and multiple aortic stenosis: a case report with brief review of the literature

One-stage surgery was successfully performed in a 44-year-old hypertensive man with uncontrolled angina, multiple coarctations of the thoracic and abdominal aorta, and a previous subtotal gastrectomy. There was a gradient of 120 mm Hg between the thoracic and abdominal aorta. A graft was placed retroperitoneally from the infrarenal aorta to the ascending aorta and was followed by a coronary artery bypass graft. Twenty-four months postoperatively, the patient was free of angina, and his hypertension was easily controlled.     

Prevalence of apical periodontitis detected in cone beam CT images of a Brazilian subpopulation

Objectives

The aim of this study was to determine the prevalence of apical periodontitis (AP) detected in cone beam CT (CBCT) images from a database.

Methods

CBCT images of 300 Brazilian patients were assessed. AP images were measured in three dimensions. Age, gender, number and location of total teeth in each patient were considered. AP location was considered according to tooth groups. The extent of AP was determined by the largest diameter in any of the three dimensions. Percentages and the χ² test were used for statistical analysis.

Results

AP was found in 51.4% of the patients and in 3.4% of the teeth. Higher prevalence of AP was found in 60- to 69-year-olds (73.1%) and in mandibular molars (5.9%) (p < 0.05). Inadequate endodontic treatment presented higher prevalence of AP (78.1%).

Conclusions

AP can be frequently found in CBCT examinations. The presence of AP has a significant association with patients'' age, and tooth type and condition. CBCT databases are useful for cross-sectional studies about AP prevalence in a population.     

Potential improvements in the therapeutic ratio of prostate cancer irradiation: dose escalation of pathologically identified tumour nodules using intensity modulated radiotherapy

The potential of intensity modulated radiotherapy (IMRT) to improve the therapeutic ratio in prostate cancer by dose escalation of intraprostatic tumour nodules (IPTNs) was investigated using a simultaneous integrated boost technique. The prostate and organs-at-risk were outlined on CT images from six prostate cancer patients. Positions of IPTNs were transferred onto the CT images from prostate maps derived from sequential large block sections of whole prostatectomy specimens. Inverse planned IMRT dose distributions were created to irradiate the prostate to 70 Gy and all the IPTNs to 90 Gy. A second plan was produced to escalate only the dominant IPTN (DIPTN) to 90 Gy, mimicking current imaging techniques. These plans were compared with homogeneous prostate irradiation to 70 Gy using dose-volume histograms, tumour control probability (TCP) and normal tissue complication probability (NTCP) for the rectum. The mean dose to IPTNs was increased from 69.8 Gy to 89.1 Gy if all the IPTNs were dose escalated (p=0.0003). This corresponded to a mean increase in TCP of 8.7-31.2% depending on the alpha/beta ratio of prostate cancer (p<0.001), and a mean increase in rectal NTCP of 3.0% (p<0.001). If only the DIPTN was dose escalated, the TCP was increased by 6.4-27.5% (p<0.003) and the rectal NTCP was increased by 1.8% (p<0.01). In the dose escalated DIPTN IMRT plans, the highest rectal NTCP was seen in patients with IPTNs in the posterior peripheral zone close to the anterior rectal wall, and the lowest NTCP was seen with IPTNs in the lateral peripheral zone. The ratio of increased TCP to NTCP may represent an improvement in the therapeutic ratio, but was dependent on the position of the IPTN relative to the anterior rectal wall. Improvements in prostate imaging and prostate immobilization are required before clinical implementation would be possible. Clinical trials are required to confirm the clinical benefits of these improved dose distributions.     

Predictors of positive surgical margins at open and robot-assisted laparoscopic radical prostatectomy: a single surgeon series

Robot-assisted laparoscopic radical prostatectomy (RALRP), increasingly used to treat localized prostate cancer, has advantages over open radical prostatectomy (ORP) in terms of reduced bleeding and quicker convalescence. However, debate continues over whether RALRP provides superior or at least equivalent surgical outcomes. This study compares positive surgical margins (+SM), as a surrogate for long-term cancer control, at RALRP and ORP performed by a single experienced surgeon during the process of taking up RALRP. 400 consecutive patients undergoing surgery for prostate cancer under a single surgeon (DW) between November 1999 and July 2009 were studied. Prior to July 2005, all patients underwent ORP; after this date, most patients were treated by RALRP. Data were collected by retrospective chart review and analysed independently of the treating surgeon. +SM were defined as the presence of cancer at an inked surface. Overall, 23 (11.5%) of 200 patients undergoing RALRP had +SM, compared to 40 (20.0%) of 200 patients undergoing ORP (P?<?0.05). On univariate logistic regression analysis, in addition to surgical approach (odds ratio [OR]?=?1.92), patient age (OR?=?1.05), pathologic stage (OR?=?3.93) and specimen Gleason (GS) score (OR?=?1.86) were significant predictors of +SM. On multivariate analysis, surgical approach, p-stage and specimen GS remained significant predictors of +SM. RALRP is associated with lower rates of +SM compared to ORP, even after adjusting for other known risk factors. Of note, the RALRP in this study were part of the surgeon??s learning curve.     

Re-evaluation ofim ephedrine as prophylaxis against hypotension associated with spinal anaesthesia for Caesarean section

Purpose

To assess the safety and efficacy of 37.5 mg ephedrineim in preventing hypotension associated with spinal anaesthesia for Caesarean section.

Methods

In a double-blind randomised controlled study, 40 patients (20 in each group) were given either 37.5 mg ephedrine or placeboim. The following parameters were recorded: (i) blood pressure; (ii) heart rate; (iii) ephedrineiv supplementation; (iv) umbilical venous blood gases and neonatal Apgar scores.

Results

The incidence of hypertension in the study group was 30% compared with 20% for the control group (P:NS). There was no difference in mean highest blood pressure or mean highest heart rate between the groups. The incidence of hypotension was lower but not significantly lower in the study group (50%) than in the control group (80%) (P:NS). However, the incidence of delayed hypotension was only 10% in the study group patients compared with 50% in the control group patients (P < 0.05).

Conclusion

Giving 37.5 mg ephedrineim prior to spinal anaesthesia was not associated with reactive hypertension or tachycardia. Intramuscular ephedrine provided more sustained cardiovascular support than intravenous ephedrine.     

Interleukin-6 predicts hypoalbuminemia, hypocholesterolemia, and mortality in hemodialysis patients

Low serum albumin and low serum cholesterol levels are among the most consistent predictors of mortality in patients with end-stage renal disease (ESRD) undergoing hemodialysis. Hypoalbuminemia is often interpreted as a marker of poor nutrition, but serum albumin and cholesterol levels can also be low as part of a cytokine-mediated acute-phase reaction to acute or chronic inflammation. Here we report the results from a 900-day prospective study designed to determine whether tumor necrosis factor-alfa (TNF-alpha) and interleukin-6 (IL-6) predict serum albumin and cholesterol levels and mortality in a group of 90 ambulatory, adult hemodialysis patients with no acute infection, hospitalization or surgery, and no known acquired immunodeficiency syndrome (AIDS), malignancy, or liver disease. Measurable levels of TNF-alpha and/or IL-6 were found in 89 of 90 patients. Significant relationships were found between TNF-alpha and IL-6 and the degree of hypoalbuminemia and dyslipoproteinemia. IL-6 was the strongest predictor of mortality in univariate and multivariate analysis, followed by age, albumin level, and body mass index (BMI). Although the cause of hypercytokinemia was not addressed in this study, the data support the view that hypoalbuminemia and hypocholesterolemia are negative acute-phase responses to inflammatory stimuli. These results suggest that efforts to identify the nature of the stimuli for cytokine production and to lower cytokine levels in hemodialysis patients might be effective in improving the survival of patients undergoing hemodialysis.