High Tregs and systemic IL-10 expressions linked to the absence of sheath antibodies in lymphatic filariasis: implications on the persistence of residual infection

The persistence of residual infection is one of the major factors in failure of the Global Programme to Eliminate Lymphatic Filariasis (GPELF). The present study aims to explore the status of sheath antibody and regulatory T cells (Tregs) known to play key roles in clearance of parasite and patent filarial infection, in individuals with residual infection after MDA. A total of 61 microfilaremic (Mf) individuals were followed up after at least 6 rounds of MDA. Infection status of subjects was assessed through the detection of Mf and circulating filarial antigen (CFA). Antibodies to Mf sheath were determined by immuno-peroxidase assay (IPA). The expression of Tregs was measured by a flow cytometer. IL-10 and IFN-γ were evaluated using the commercially available ELISA kit. The sheath antibody was present in subjects who have cleared both Mf and CFA and absent in individuals who were found to be Mf /CFA positive. Further individuals carrying infection have significantly high levels of Tregs and IL-10. A positive correlation was observed between Tregs, IL-10, and CFA in infected individuals. In contrast, a negative correlation was observed between IFN-γ and IL-10 in both infected and uninfected subjects. Our study reveals that the absence of a sheath antibody and a high level of Tregs and IL-10 are the hallmarks of the persistence of residual filarial infection.

     

Radiotherapy and radiosensitizers in the treatment of glioblastoma multiforme

Effective treatment of glioblastoma multiforme (GBM) is complicated by multiple factors, including the diffusely infiltrative nature of the disease, which limits complete surgical resection; the difficulty in overcoming the blood-brain barrier with systemic therapies; and the challenge of identifying novel means of treating the residual hypoxic tumor cells that are relatively resistant to radiotherapy (RT) and chemotherapy. Clear survival advantages have been demonstrated with postresection RT to doses of 5,000-6,000 cGy, but further attempts at dose escalation over 6,000 cGy have resulted in increased toxicity without a survival benefit. In an effort to improve local control of tumor and limit toxicity to normal brain tissue, novel imaging techniques (eg, chemical shift imaging) are being explored in order to better define RT fields. Brachytherapy and stereotactic radiosurgery are effective therapies for relapsed GBM but have undefined roles outside of clinical trials in treating newly diagnosed GBM. Stereotactic RT may have a survival advantage in subgroups that have undergone a gross total resection and have favorable (recursive partitioning analysis class IV) disease. In contrast, experience with hyperfractionated RT in GBM has shown that survival outcomes may actually be unfavorable in certain patient subgroups. Novel means of delivering RT, including radioimmunotherapy, have demonstrated efficacy with acceptable toxicity. Systemic agents are being explored as potential radiosensitizers, with the recent emergence of temozolomide as a model radiosensitizing agent having a positive impact on survival. Ongoing investigations are evaluating temozolomide in combination with other systemic agents, and additional agents (eg, motexafin gadolinium, mammalian target of rapamycin inhibitors, farnesyltransferase inhibitors) have shown promising activity in combination with RT.     

Distribution of brain metastases in relation to the hippocampus: implications for neurocognitive functional preservation

PURPOSE: With the advent of intensity-modulated radiotherapy, the ability to limit the radiation dose to normal tissue offers an avenue to limit side effects. This study attempted to delineate the distribution of brain metastases with relation to the hippocampus for the purpose of exploring the viability of tomotherapy-guided hippocampal sparing therapy potentially to reduce neurocognitive deficits from radiation. METHODS AND MATERIALS: The pre-radiotherapy T1-weighted, postcontrast axial MR images of 100 patients who received whole brain radiotherapy, stereotactic radiosurgery, or a radiosurgical boost following whole brain radiotherapy between 2002 and 2006 were examined. We contoured brain metastases as well as hippocampi with 5-, 10-, and 15-mm expansion envelopes. RESULTS: Of the 272 identified metastases, 3.3% (n = 9) were within 5 mm of the hippocampus, and 86.4% of metastases were greater than 15 mm from the hippocampus (n = 235). The most common location for metastatic disease was the frontal lobe (31.6%, n = 86). This was followed by the cerebellum (24.3%, n = 66), parietal lobe (16.9%, n = 46), temporal lobe (12.9%, n = 35), occipital lobe (7.7%, n = 21), deep brain nuclei (4.0%, n = 11), and brainstem (2.6%, n = 7). CONCLUSIONS: Of the 100 patients, 8 had metastases within 5 mm of the hippocampus. Hence, a 5-mm margin around the hippocampus for conformal avoidance whole brain radiotherapy represents an acceptable risk, especially because these patients in the absence of any other intracranial disease could be salvaged using stereotactic radiosurgery. Moreover, we developed a hippocampal sparing tomotherapy plan as proof of principle to verify the feasibility of this therapy in the setting of brain metastases.     

Supercyclone in Orissa: an assessment of psychological status of survivors

The study assessed the impact of the Orissa supercyclone on survivors' locus of control, anxiety, depression, and posttraumatic stress. The study was conducted in structured interview sessions 3 months after the supercyclone. The affected people (n = 65) who were close to the epicenter of supercyclone and lost their family members, relatives, and property, experienced more anxiety, depression, and posttraumatic stress than the unaffected (n = 65) who were away from the epicenter of supercyclone and had not experienced any loss. Effects of exposure remained significant with the effects of sex and neuroticism controlled. External support reduced anxiety and depression, and the amount of loss experienced by the survivors significantly increased external locus of control and anxiety.     

Non-cytotoxic radiosensitizers in brain radiotherapy: journey till the first decade of this millennium

Brain tumors, primary and metastatic, are a cause of significant mortality and morbidity. Radiotherapy (RT) forms an integral part of the treatment of brain tumors. Intrinsic relative tumor radio-resistance, normal tissue tolerance and impact on neurocognitive function, all limit the efficacy of RT. Radiosensitizers can potentially increase efficacy on tumors while maintaining normal tissue toxicity, with or without inherent cytotoxicity. This article reviews the evolution of evidence with use of non-cytotoxic radiosensitizers in brain radiotherapy and their status at the end of the first decade of this millennium. Considering, the era of development and mechanism of action, these agents are classified as first, second and third-generation non-cytotoxic radiosensitizers. The last millennium involved elaboration of first-generation compounds including halogenated pyrimidines, hypoxic cell sensitizers (e.g. imidazoles) and glycolytic inhibitors (e.g. lonidamine). The first decade of this millennium has highlighted redox modulators like motexafin gadolinium and newer hypoxic cell sensitizers like efaproxiral, which have shown promise. However, phase III trials and meta-analyses have not identified a clear winner though the second-generation has shown some rays of hope. Recent research has focused on expanding the horizon by studying modulation of newer molecular pathways like DNA repair, microtubule stabilization, cytokine function and nuclear factor-kappa beta (NF-KB) in order to increase RT efficacy. The review concludes by summarizing the class of evidence and the level of recommendation available for use of non-cytotoxic radiosensitizers in brain RT.     

Significant suppression of radiation dermatitis in breast cancer patients using a topically applied adrenergic vasoconstrictor

Background

Our previous studies showed that vasoconstrictor applied topically to rat skin minutes before irradiation completely prevented radiodermatitis. Here we report on a Phase IIa study of topically applied NG12-1 vasoconstrictor to prevent radiodermatitis in post-lumpectomy breast cancer patients who received at least 40 Gray to the whole breast using standard regimens.

Methods

Patients had undergone surgery for Stage Ia, Ib, or IIa infiltrating ductal or lobular carcinoma of the breast or ductal carcinoma in situ. NG12-1 formulation was applied topically to the same 50-cm² treatment site within the radiation field 20 min before each daily radiotherapy fraction.

Results

Scores indicated significant reductions in radiodermatitis at the NG12-1 treatment site versus control areas in the same radiotherapy field. The mean dermatitis score for all subjects was 0.47 (SD 0.24) in the NG12-1-treated area versus 0.72 (SD 0.22) in the control area (P =?0.022). Analysis by two independent investigators indicated radiodermatitis reductions in 9 of the 9 patients with scorable radiodermatitis severity, and one patient with insufficient radiodermatitis to enable scoring. There were no serious adverse events from NG12-1 treatment.

Conclusions

Thirty, daily, NG12-1 treatments, topically applied minutes before radiotherapy, were well tolerated and conferred statistically significant reductions in radiodermatitis severity (P =?0.022).

Trial registration

NCT01263366; clinicaltrials.gov

     

Memantine for the prevention of cognitive dysfunction in patients receiving whole-brain radiotherapy: a randomized,double-blind,placebo-controlled trial

Background

To determine the protective effects of memantine on cognitive function in patients receiving whole-brain radiotherapy (WBRT).

Methods

Adult patients with brain metastases received WBRT and were randomized to receive placebo or memantine (20 mg/d), within 3 days of initiating radiotherapy for 24 weeks. Serial standardized tests of cognitive function were performed.

Results

Of 554 patients who were accrued, 508 were eligible. Grade 3 or 4 toxicities and study compliance were similar in the 2 arms. There was less decline in delayed recall in the memantine arm at 24 weeks (P = .059), but the difference was not statistically significant, possibly because there were only 149 analyzable patients at 24 weeks, resulting in only 35% statistical power. The memantine arm had significantly longer time to cognitive decline (hazard ratio 0.78, 95% confidence interval 0.62–0.99, P = .01); the probability of cognitive function failure at 24 weeks was 53.8% in the memantine arm and 64.9% in the placebo arm. Superior results were seen in the memantine arm for executive function at 8 (P = .008) and 16 weeks (P = .0041) and for processing speed (P = .0137) and delayed recognition (P = .0149) at 24 weeks.

Conclusions

Memantine was well tolerated and had a toxicity profile very similar to placebo. Although there was less decline in the primary endpoint of delayed recall at 24 weeks, this lacked statistical significance possibly due to significant patient loss. Overall, patients treated with memantine had better cognitive function over time; specifically, memantine delayed time to cognitive decline and reduced the rate of decline in memory, executive function, and processing speed in patients receiving WBRT.RTOG 0614, ClinicalTrials.gov number CT00566852.