Patterns of relapse after successful completion of initial therapy in primary central nervous system lymphoma: a case series

Journal of Neuro-Oncology - Primary central nervous system lymphoma (PCNSL) is a subtype of non-Hodgkin’s lymphoma that involves the brain, spinal cord, or leptomeninges, without evidence of...     

The effect of a sodium lauryl sulfate-free dentifrice on patients with recurrent oral ulceration

OBJECTIVE: Sodium lauryl sulphate (SLS) is the most commonly used detergent in dentifrices. Recent reports have suggested that it may exacerbate conditions with compromised epithelial integrity. The aim of this study was to compare the effect of an SLS-free dentifrice and an SLS-containing dentifrice on recurrent oral ulceration (ROU). DESIGN: A double-blind crossover clinical trial was carried out during which subjects used an SLS dentifrice for 8 weeks and an SLS-free dentifrice for 8 weeks. Each phase was preceded by a 2-week washout period. SETTING: A UK dental teaching hospital. SUBJECTS AND METHODS: Forty-seven subjects completed the trial. They were all in the age range 10-62 years, had regularly recurrent oral ulceration reporting at least one to two ulcers per month and had normal levels of vitamin B12, ferritin and folate. MAIN OUTCOME MEASURES: The trial phases were compared for the following ulcer parameters--number of ulcer days, total pain scores, number of ulcer episodes, and number of ulcers. Additional parameters compared were the number of ulcers per episode, ulcer duration, total pain per episode and ulcer size. RESULTS: None of the ulcer parameters measured was significantly affected by the use of the SLS-free dentifrice as compared with the SLS dentifrice. CONCLUSION: SLS-free dentifrice had no significant effect on ulcer pattern in the ROU study group.     

Double-Blind Whitening Night-Guard Study Using Ten Percent Carbamide Peroxide

The conservative technique of professionally dispensed and supervised, home-administered vital bleaching is now a routine treatment in the dental profession. This double-blind study evaluated the Rembrandt Lightening Gel and Whitening Toothpaste for shade change, colorimeter shade change. As well, it evaluated soft tissue health by periodontal probing, plaque index, and bleeding index. A patient questionnaire evaluated perception of whitening, perception of oral hygiene, average hours per day, and average days per week. Bleaching trays were worn over a 4-week period. The bleaching system showed definitive whitening effects as evaluated with the Vita shade guide and the colorimeter. The bleaching system had no deleterious effects on the soft tissue. The Rembrandt toothpaste alone demonstrated two-shade lightening. This vital bleaching system shows definitive whitening of the teeth in short periods of time with no adverse effects.     

Malignant tumours of the small intestine

Adenocarcinoma, neuroendocrine tumours, sarcomas and lymphomas are the four most common malignant tumours arising in the small intestine, although over forty different histological subtypes are described. Collectively these account for only 2% of cancers of the digestive system. The incidence of small bowel cancer has increased in recent decades with a four-fold increase in carcinoid tumours. Risk factors for small bowel tumours include coeliac disease, inflammatory bowel disease and a number of genetic abnormalities. The non-specific nature of their symptoms and the difficulty in visualising these tumours with normal endoscopic techniques often results in late diagnosis. Furthermore the paucity of literature on this topic has made it difficult to standardise management. There has however been marked improvement in imaging methods resulting in earlier diagnosis in many cases. As expected, early detection of localised, well differentiated tumours followed by surgical resection with negative margins offers the best chance of long term survival. Better adjuvant treatment, notably for gastrointestinal stromal tumours, has improved 5-year survival rates significantly. Development of surveillance guidelines for at risk populations may be a valuable way of improving early diagnosis of this challenging group of conditions.     

Biomechanical analysis of the upper thoracic spine after decompressive procedures

Background contextDecompressive procedures such as laminectomy, facetectomy, and costotransversectomy are routinely performed for various pathologies in the thoracic spine. The thoracic spine is unique, in part, because of the sternocostovertebral articulations that provide additional strength to the region relative to the cervical and lumbar spines. During decompressive surgeries, stability is compromised at a presently unknown point.PurposeTo evaluate thoracic spinal stability after common surgical decompressive procedures in thoracic spines with intact sternocostovertebral articulations.Study designBiomechanical cadaveric study.MethodsFresh-frozen human cadaveric spine specimens with intact rib cages, C7–L1 (n=9), were used. An industrial robot tested all spines in axial rotation (AR), lateral bending (LB), and flexion-extension (FE) by applying pure moments (±5 Nm). The specimens were first tested in their intact state and then tested after each of the following sequential surgical decompressive procedures at T4–T5 consisting of laminectomy; unilateral facetectomy; unilateral costotransversectomy, and subsequently instrumented fusion from T3–T7.ResultsWe found that in all three planes of motion, the sequential decompressive procedures caused no statistically significant change in motion between T3–T7 or T1–T12 when compared with intact. In comparing between intact and instrumented specimens, our study found that instrumentation reduced global range of motion (ROM) between T1–T12 by 16.3% (p=.001), 12% (p=.002), and 18.4% (p=.0004) for AR, FE, and LB, respectively. Age showed a negative correlation with motion in FE (r=?0.78, p=.01) and AR (r=?0.7, p=.04).ConclusionsThoracic spine stability was not significantly affected by sequential decompressive procedures in thoracic segments at the level of the true ribs in all three planes of motion in intact thoracic specimens. Age appeared to negatively correlate with ROM of the specimen. Our study suggests that thoracic spinal stability is maintained immediately after unilateral decompression at the level of the true ribs. These preliminary observations, however, do not depict the long-term sequelae of such procedures and warrant further investigation.     

Amikacin population pharmacokinetics among paediatric burn patients

Introduction

The objectives of this study were to (1) determine the pharmacokinetics of amikacin among children with severe burn and (2) identify influential covariates.

Methods

Population-based pharmacokinetic modelling was performed in NONMEM 7.2 for hospitalized children who received amikacin at 10–20 mg/kg divided two, three, or four times per day as part of early empiric treatment of presumed burn-related sepsis.

Results

The analysis included data from 70 patients (6 months to 17 years) with 282 amikacin serum concentrations. Amikacin's mean C_max was 33.2 ± 9.4 μg/mL and the mean C_min was 3.8 ± 4.6 μg/mL. The final covariate model estimated clearance as 5.98 L/h/70 kg (4.97–6.99, 95% CI), the volume of distribution in the central compartment as 16.7 L/70 kg (14.0–19.4, 95% CI), the volume of distribution in the peripheral compartment as 40.1 L/70 kg (15.0–80.4, 95% CI), and the inter-compartmental clearance as 3.38 L/h/70 kg (2.44–4.32, 95% CI). In multivariate analyses, current weight (P < 0.001) was a significant covariate, while age, sex, height, serum creatinine, C-reactive protein, platelet count, the extent and type of burn, and concomitant vancomycin administration did not influence amikacin pharmacokinetics.

Discussion

Children with burn featured elevated amikacin clearance when compared to healthy adult volunteers. However, peak amikacin concentrations are comparable to those attained in other critically-ill children, suggesting that elevated amikacin clearance may not result in sub-therapeutic antibacterial effects. In this study, we found that amikacin displays two-compartment pharmacokinetics, with weight exerting a strong effect upon amikacin clearance. Further pharmacodynamic studies are needed to establish the optimal dosing regimen for amikacin in paediatric burn patients.