Diagnosis of the condition of the dental pulp: a systematic review

The aim of this systematic review was to appraise the diagnostic accuracy of signs/symptoms and tests used to determine the condition of the pulp in teeth affected by deep caries, trauma or other types of injury. Radiographic methods were not included. The electronic literature search included the databases PubMed, EMBASE, The Cochrane Central Register of Controlled Trials and Cochrane Reviews from January 1950 to June 2011. The complete search strategy is given in an Appendix S1 (available online as Supporting Information). In addition, hand searches were made. Two reviewers independently assessed abstracts and full-text articles. An article was read in full text if at least one of the two reviewers considered an abstract to be potentially relevant. Altogether, 155 articles were read in full text. Of these, 18 studies fulfilled pre-specified inclusion criteria. The quality of included articles was assessed using the QUADAS tool. Based on studies of high or moderate quality, the quality of evidence of each diagnostic method/test was rated in four levels according to GRADE. No study reached high quality; two were of moderate quality. The overall evidence was insufficient to assess the value of toothache or abnormal reaction to heat/cold stimulation for determining the pulp condition. The same applies to methods for establishing pulp status, including electric or thermal pulp testing, or methods for measuring pulpal blood circulation. In general, there are major shortcomings in the design, conduct and reporting of studies in this domain of dental research.     

Surgical delivery of drug releasing poly(lactic-co-glycolic acid)/poly(ethylene glycol) paste with in vivo effects against glioblastoma

Introduction

The median survival of patients with glioblastoma multiforme (astrocytoma grade 4) remains less than 18 months despite radical surgery, radiotherapy and systemic chemotherapy. Surgical implantation of chemotherapy eluting wafers into the resection cavity has been shown to improve length of survival but the current licensed therapy has several drawbacks. This paper investigates in vivo efficacy of a novel drug eluting paste in glioblastoma.

Methods

Poly(lactic-co-glycolic acid)/poly(ethylene glycol) (PLGA/PEG) self-sintering paste was loaded with the chemotherapeutic agent etoposide and delivered surgically into partially resected tumours in a flank murine glioblastoma xenograft model.

Results

Surgical delivery of the paste was successful and practical, with no toxicity or surgical morbidity to the animals. The paste was retained in the tumour cavity, and preliminary results suggest a useful antitumour and antiangiogenic effect, particularly at higher doses. Bioluminescent imaging was not affected significantly by the presence of the paste in the tumour.

Conclusions

Chemotherapy loaded PLGA/PEG paste seems to be a promising technology capable of delivering active drugs into partially resected tumours. The preliminary results of this study suggest efficacy with no toxicity and will lead to larger scale efficacy studies in orthotopic glioblastoma models.     

Platelet-derived growth factor in vivo: levels, activity, and rate of clearance

Platelet-derived growth factor (PDGF) is a potent mitogen for many cultured connective tissue cells. It is present in concentrated form within the platelet alpha-granules and is believed to be released during platelet degranulation at sites of vascular injury. We have used a sensitive radioreceptor assay to measure PDGF levels in whole blood serum from normal humans [17.5 +/- 3.1 (SD) ng/mL] and baboons (2.7 +/- 1.2 ng/mL). PDGF was not detected in plasma from either species. In addition, plasma was found to substantially reduce the ability of added purified PDGF to bind to the cell surface PDGF receptor on cultured cells, suggesting that plasma may contain a PDGF-binding protein that would serve to inactivate PDGF released into plasma. Calculations of PDGF concentrations in serum have been corrected for the effects of the binding protein. 125I-PDGF injected intravenously into normal baboons was cleared rapidly from the plasma (t1/2 = two minutes). The rapid clearance of 125I-PDGF did not result from iodination damage, as purified unlabeled PDGF was cleared with comparable kinetics. The rapid clearance of purified and iodinated PDGF did not result from changes in PDGF structure during purification or from removal of PDGF-associated proteins during purification, as PDGF present in freeze-thaw lysates of fresh platelets was cleared equally rapidly. We conclude that release of PDGF at sites of vascular injury would greatly increase the local concentration of PDGF and that PDGF not localized to the site of injury would be rapidly cleared from the circulation.     

Percutaneous radiofrequency ablation of renal tumours: Case series of 11 tumours and review of published work

Detection of renal cell carcinoma (RCC) is increasing with the greater use of cross‐sectional imaging and up to two‐thirds of RCCs are discovered incidentally in asymptomatic patients. The traditional option of nephrectomy or partial nephrectomy may not always be appropriate. A minimally invasive treatment alternative is radiofrequency ablation (RFA). We retrospectively reviewed the RFA cases for renal tumours at our institution between January 2004 and June 2006. Thirteen RFA treatment sessions were conducted for 11 neoplasms in 11 patients. Mean patient age was 74.4 years (61–88 years). Imaging was carried out after ablation with a mean follow up of 8.0 months (2–26 months). No residual tumour was observed after the first RFA treatment in 82% of patients (nine of 11). Two patients required a second RFA treatment for residual (one) or recurrent tumour (one). RFA is emerging as a useful technique for treatment of small renal tumour. A number of short‐term studies reflect this, however, long‐term findings are still lacking.     

Hypothyroxinemia of prematurity and infant neurodevelopment: a pilot study

To assess whether hypothyroxinemia has specific effects on neurodevelopment in premature infants, thyroid hormone levels were determined at 2 weeks of life and 40 weeks postconceptional age (PCA), and infants were evaluated at 3 months corrected age using the Bayley Scales of Infant Development and Early Infancy Temperament Questionnaire. Additional attention scales were derived from the factor analysis of relevant Bayley items. Fifteen infants born between 30 and 35 weeks and 21 full-term infants were studied. Results indicated no group differences on the Bayley or derived attention scales, whereas the temperament questionnaire revealed lower sensory thresholds and greater reactivity in the preterm group. The preterm group had normal thyroxine (T4) levels at 2 weeks of age, which declined by 40 weeks PCA for both free T4 (p < .01 for reference value and p < .0001 for gestational age-adjusted value) and total T4 (p < .05 for age-adjusted value). Correlations revealed that higher 40-week PCA free T4 levels were associated with better attentiveness ratings (p < .01 for reference and p < .0001 for gestational-age values) and sustained attention (p < .05) and higher 40-week total T4 with better motor skills (p < .05 for gestational-age value). These findings signify that a mild degree of hypothyroxinemia is evident in preterm infants without neurological risk and predicts subsequently poorer cognitive and motor abilities.     

External Cephalic Version at Term

Summary: The case notes of women with singleton term (37 weeks' gestation and beyond) breech presentation and delivery were retrospectively reviewed. Thirty-two of the 72 women in the study group had attempted external cephalic version at term, with a success rate of 53% (17 women). The Caesarean section rate was significantly lower in the group which had attempted ECV compared to the group which did not.     

Deletions and altered expression of the RIZ1 tumour suppressor gene in 1p36 in pheochromocytomas and abdominal paragangliomas

Pheochromocytomas and abdominal paragangliomas are rare catecholamine-producing tumours arising from neural crest-derived chromaffin cells. Frequent deletions of several distinct regions on the short arm of chromosome 1 suggest their involvement in the tumourigenesis process. The RIZ1 tumour suppressor encoded by the RIZ gene in 1p36.21 represents an attractive candidate target for the distal 1p deletions in these tumours. A panel of 18 pheochromocytomas (14 benign, and 4 malignant) and 11 abdominal paragangliomas (4 benign, and 7 malignant) were characterised for somatic deletions and mRNA expression status of RIZ1 using loss of heterozygosity (LOH) analysis and real-time quantitative PCR, respectively. Furthermore, we evaluated the methylation status of the RIZ1 promoter utilising methylation-specific PCR (MSP). Intragenic LOH at the RIZ locus was detected in 10 of 16 informative cases (62%), including 8 of 12 pheochromocytomas (67%) and 2 of 4 paragangliomas (50%). RIZ1 mRNA appeared to be significantly under-expressed in the tumour samples compared to normal adrenal controls (mean 0.6 vs. 1.0, p<0.001). This was not associated with RIZ1 promoter methylation in any of the samples, indicating that promoter hypermethylation is unlikely to be the underlying cause of the frequent expressional silencing. The recurrent inactivation of the tumour suppressor RIZ1 suggests that this event may be a significant contributing factor to tumour development in pheochromocytomas and abdominal paragangliomas.