Metastasis in meningioma

Summary Meningioma is a neoplastic growth originating from the leptomeninges. Although meningiomas are usually benign, malignant meningiomas with distant metastases occur infrequently. There is little precise information in the literature regarding the frequency of metastases in meningiomas; their incidence has been vaguely reported to be less than 1 per 1,000. Furthermore, most of the previous studies have also included haemangiopericytomas which most recent authorities do not consider meningiomas. In our experience with the management of 396 meningiomas over the past 18 years, 7 meningiomas were classified as malignant by defined histological criteria. After initially presenting as solitary intracranial neoplasms, three of the malignant meningiomas metastasized to extracranial tissues. Collectively, the metastases involved the vertebral bodies, liver, pelvis, long bones, and the spinal cord. This confers an incidence of metastasis of 0.76% when considering all the meningiomas, and an incidence of approximately 43% when considering only malignant meningioma; both percentages are significantly higher than reported previously. This high incidence of metastasis in the malignant meningioma indicates a worse prognosis than formerly assessed and also characterizes the malignant meningioma as a primary central nervous system neoplasm with one of the highest rates of metastasis. In addition, when malignant meningioma is classified by following strict criteria, the risk of metastasis in the ensuing clinical course can be predicted with a higher reliability.     

Comparison of three commercially available softwares for measuring left ventricular perfusion and function by gated SPECT myocardial perfusion imaging

Background

The three softwares, Quantitative Perfusion SPECT (QPS), Emory Cardiac Toolbox, and 4 Dimension-Myocardial SPECT (4DM) are widely used with myocardial perfusion imaging (MPI) to determine perfusion defect size (PDS) and left ventricular (LV) function. There are limited data on the degree of agreement between these methods in quantifying the LV perfusion pattern and function.

Methods and Results

In 120 consecutive patients who had abnormal regadenoson SPECT MPI with a visually derived summed stress score ≥4, the correlation between the softwares for measurements of PDS, reversible, and fixed defects was poor to fair (Spearman’s ρ = 0.18-0.72). Overall, estimation of defect size was smaller by QPS and larger by 4DM. There was discordance among the softwares in 62% of the cases in defining PDS as small/moderate/large. The correlation between the softwares was better for measuring LVEF, volumes and mass (ρ = 0.84-0.97), and discrepant results for defining normal/mild-moderate/severe LV systolic dysfunction were prevalent in 28% of the patients.

Conclusion

There are significant differences between the softwares in measuring PDS as well as LV function, and more importantly in defining small, moderate, or large ischemic burden. These results suggest the necessity of using the same software when assessing interval changes by serial imaging.     

Curcuminoids rescue long-term potentiation impaired by amyloid peptide in rat hippocampal slices

Curcuminoids are vital constituent of turmeric, with therapeutic potential in the treatment of Alzheimer's disease. Electrically, stimulus train-elicited plastic changes in hippocampal CA1 excitability were used as an experimental paradigm to study the effects of curcuminoid mixture and individual components on functional failure induced by Aβ peptide in vitro. Electrical stimulation was applied on Schaffer collaterals, and population spikes (PS) were recorded from stratum pyramidale. To induce long-term potentiation (LTP) of PS, primed burst stimulation (PBs) was used. Aβ peptide inhibited PS LTP induction. Sinking PS LTP due to Aβ peptide was rescued when curcuminoid mixture was applied before PBs only at lower dose (0.1 μM) resulting in PS potentiation to 127.42% ± 1.83% at 5 min and 123.98% ± 1.06% at 60-min post-PBs. Similarly, when bisdemethoxycurcumin was applied, PS LTP was induced and lasted only at a single dose (0.1 μM). Demethoxycurcumin was effective at a middle dose (1 μM), so that the PS amplitude was changed to 140.15% ± 2.68% and 129.82% ± 0.44% at 5 and 60 min, respectively. PS LTP was effectively induced in the presence of curcumin at middle and high doses (1 and 30 μM) with resultant PS LTP to 155.68% ± 1.23% and 127.72% ± 1.23%, respectively, at 60-min post-PBs. These results showed that curcuminoids can restore susceptibility for plastic changes in CA1 excitability that is injured by exposure to Aβ peptide and rescue sinking PS LTP in Aβ-peptide-exposed hippocampal CA1 neurons.     

Neurosurgical research in Pakistan: trends of publication and quality of evidence

Objective

To analyze the output and quality of neurosurgical research published from Pakistan in indexed peer reviewed journals.

Methods

Indexed peer reviewed publications from 2003 to 2008 were searched for neurosurgical contributions from Pakistan. The retrieved articles were evaluated to analyze the trends of publication and quality of evidence.

Results

Sixty-two neurosurgical research papers (10.3 per year, range 8-13) were published from Pakistan during the study period. Twenty-four (38.7%) publications were the contribution of just four primary authors; 25 (45.3%) of the publications were original research articles and 30 (48.4%) were either case reports or case series; and 38 (61.3%) of all the publications were from just three institutions in the country. Majority of publications were pertaining to neurooncology (n = 23, 37.1%) and neurosurgical trauma (n = 16, 25.8%). Overall, 48 (77.4%) papers were published in local indexed journals and only 14 (22.6%) in international journals. There were no basic science studies, and no papers offering level 1 or 2 evidence were published during the study period.

Conclusion

Neurosurgical research in Pakistan over the past six years has been unsatisfactory, both in terms of number and quality of publications. Analysis of six year publications also did not show any significant improvement in research trends.     

Trials on the effect of cardiac resynchronization on arterial blood pressure in patients with heart failure

Cardiac resynchronization therapy (CRT) increases cardiac performance in patients with heart failure, but its effect on arterial pressure is not well established. To determine the effect of CRT on systolic blood pressure (SBP), diastolic blood pressure (DBP), and pulse pressure (PP) a systematic review using standard nomenclatures for CRT was done in Scopus (MEDLINE and Embase), Cochrane Controlled Trials Register, National Institutes of Health http://www.ClinicalTrials.gov database, and bibliography of select meta-analyses for studies evaluating CRT in patients with dilated cardiomyopathy. Two independent investigators extracted the articles based on predefined criteria. The primary outcome was difference in arterial pressure parameters from baseline to after CRT in nonrandomized cohort trials. This was then validated by comparing the change in arterial pressure between CRT and medical therapy groups in randomized controlled trials. A random-effects model was used for analyses. Analyses of 15 nonrandomized studies showed that CRT resulted in an increase (from baseline) in SBP by 4.4 mm Hg (95% confidence interval [CI] 0.8 to 8.0, p = 0.02), no change in DBP (p = 0.21), and an increase in PP by 2.8 mm Hg (95% CI 1.0 to 4.6, p = 0.003). Results from the 3 randomized controlled trials were concordant with an increase in SBP by 3.9 mm Hg (95% CI 1.1 to 6.8, p = 0.007), no effect on DBP (p = 0.40), and an increase in PP by 4.3 mm Hg (95% CI 4.1 to 4.5, p <0.001) compared to medical therapy. In conclusion, CRT is associated with a modest increase in SBP and PP in patients with heart failure.     

Effect of chlorine dioxide and sodium hypochlorite on the dissolution of human pulp tissue – An in vitro study

Background

Organic tissue dissolution is an important property of an irrigant which aids in the success of root canal treatment. Recent studies have advocated the use of Chlorine dioxide as an endodontic irrigant. The aim of this study is to compare the dissolution efficacy of chlorine dioxide and sodium hypochlorite on human pulp tissue.

Methods

In this study, 2% Sodium hypochlorite, 5% Chlorine dioxide and isotonic saline solution (control) were used. Thirty human pulp tissue specimens were exposed to three test solutions (n = 10) for 30 min following which the loss of weight was compared from the original weight by using a digital analytical balance.

Results

Sodium hypochlorite was more efficient in dissolving human pulp tissue when compared to Chlorine dioxide. Isotonic saline solution failed to dissolve any of the specimens.

Conclusion

5% Chlorine dioxide is capable of dissolving human pulp tissue but sodium hypochlorite was more effective.     

PARP inhibitors: current status and implications for anticancer therapeutics

Poly(ADP-ribose) polymerases (PARPs) comprise of a large family of 17 proteins encoded by various genes which participate in genome maintenance, apoptosis, inflammatory responses and the regulation of gene expression programs. PARP inhibitors, as therapeutic agents, come into play acting on both PARP 1 and PARP 2. These drugs seem to target tumor cells in a moment of vulnerability when they are undergoing DNA repair. In the past few years this class of anti-cancer drug has been discovered to show a promising niche in the clinic.