Adjuvant Chemoradiotherapy within One Year of Resection for Molecularly Defined Astrocytoma

PURPOSE/OBJECTIVE(S)

Treatments for diffuse low-grade gliomas (LGG) are controversial. Level I evidence supports the use of adjuvant radiotherapy (RT) and PCV chemotherapy for histologic LGG, but integration of molecular biomarkers in recent WHO classification and the emergence of temozolomide chemotherapy for gliomas necessitates additional investigation of the optimal treatment and timing of postoperative interventions. We hypothesized molecularly-defined LGG (IDH-mutant astrocytoma (astro) and IDH-mutant, 1p/19q-codeleted oligodendroglioma (oligo)) may have different clinical outcomes following adjuvant RT (aRT) with chemotherapy (aRT+chemo) vs observation or chemo alone.

MATERIALS/METHODS

A retrospective analysis of consecutive adult patients diagnosed with WHO Grade 2 astrocytoma or oligodendroglioma who underwent initial resection at a single institution from January 1998 to November 2017 was performed. Wilcoxon rank sum and Chi-squared tests were used to compare continuous and categorical variables, respectively. Survival analyses were performed using the Kaplan-Meier method and Cox proportional hazards models. Patients without clinical progression or death were censored at the date of last follow-up. Pre-operative and post-operative T2 FLAIR hyperintense tumor volumes were quantified using 3D Slicer to calculate extent of resection (EOR).

RESULTS

A total of 342 patients with molecularly-defined LGG (178 astro, 164 oligo) were identified with a median follow up of 9.1 yr. 171 (50%) patients received RT during their treatment course, of which 31 (18%) were treated with aRT within 1 year of diagnosis. The median aRT dose was 54 Gy (range: 40-60 Gy). aRT was more likely for astro (58%) vs oligo (41%, p = 0.001) and for patients who had resections with lower median EOR (88% vs 95%, p = 0.014). 53 patients (15%) were treated with chemo alone, and 136 patients (40%) were treated with aRT+chemo. Temozolomide was used for 161 patients (85%). For astro, aRT+chemo was associated with longer PFS (median 14.9 yr) compared to observation (4.8 yr, p = 0.05), aRT without chemo (5.2 yr, p = 0.01), or chemo alone (4.7 yr, p = 0.02). For oligo, aRT+chemo was associated with longer PFS (median not reached) compared to aRT without chemo (1.6 yr, p = 0.03), but not when compared to observation (median not reached, p = 0.47), or chemo alone (7.9 yr, p = 0.45). Multivariate analysis showed preoperative tumor volume, EOR, and aRT+chemo (but not aRT or chemo alone) were independently associated with astro PFS compared to observation. Propensity matching based on pre-operative tumor volume, EOR, and age demonstrated longer astro PFS after aRT+chemo (14.9 yr) compared to observation or chemo alone (4.5 yr, p = 0.015), without significant difference in OS (18.2 vs. 11.5 yr, p = 0.40).

CONCLUSION

Retrospective data from a single institution support the use of adjuvant radiotherapy with chemotherapy for patients with molecular astrocytomas, while the role of this approach for oligodendrogliomas is unclear in this cohort.

Validity of the Best Practice Tariff in paediatric major trauma: A retrospective cohort study from a level 1 children's major trauma centre

INTRODUCTION

The Best Practice Tariff (BPT) in major trauma awards Major Trauma Centres (MTCs) a financial incentive when predefined standards of care are met. However, no tailored criteria exist with regards to the reimbursement policy in paediatric major trauma. In this study, we aim to examine the utility of the paediatric Major Trauma BPT and identify predictors of additional resource utilisation.

MATERIALS AND METHODS

This cohort study encompassed all paediatric major trauma calls (N = 682) presenting to a designated combined adult and paediatric MTC between July 2014 and June 2017. Patient demographics, admission pattern, injury parameters, length of stay (LOS) and the need for operative management were collected. Patients approved for the BPT uplift payment (BPT group) were compared with the cohort of children not qualifying (non-BPT group).

RESULTS

Overall, less than a quarter (23.2%) of the trauma population qualified for the BPT. The proportion of patients requiring operative intervention and CT scanning in the BPT group was significantly higher (p<0.001). These children also attained a higher ISS (median, 13.5 vs. 0, p <0.001) and required longer hospitalisation. Following a Receiver Operator Characteristic (ROC) curve analysis, a cut off ISS score > 8 demonstrated an excellent predictive value in identifying children qualifying for BPT (true positive and false positive rates: 90% and 10.7%). However, a subgroup analysis including the more severely injured children (ISS >8) not qualifying for the uplift payment revealed that equally substantial resource went into their management - 42.9% needed surgical intervention and 57.1% a CT scan.

DISCUSSION

This study demonstrated that BPT in paediatric major trauma is a valuable reimbursement; however, our findings also unveiled a cohort deemed ineligible for BPT despite the high costs accrued. Re-evaluation of the remuneration criteria of paediatric major trauma networks with an alternative, more inclusive reimbursement policy is needed.

Applications of different solvents and conditions for differential extraction of lipopolysaccharide in Gram-negative bacteria

Lipopolysaccharide (LPS) is one of the major components in the outer membrane of Gram-negative bacteria. However, its heterogeneity and variability in different bacteria and differentiation conditions make it difficult to extract all of the structural variants. We designed a solution to improve quality and biological activity of LPS extracted from various bacteria with different types of LPS, as compared to conventional methods. We introduced a quality index as a simple measure of LPS purity in terms of a degree of polysaccharide content detected by absorbance at 204 nm. Further experiments using gel electrophoresis, endotoxin test, and macrophage activation test were performed to evaluate the performance and reliability of a proposed 'T-sol' method and the biological effectiveness and character of the LPS products. We presented that the T-sol method had differential effects on extraction of a RAW 264.7 cell-activating LPS, which was effective in the macrophage activation with similar effects in stimulating the production of TNF-alpha. In conclusion, the T-sol method provides a simple way to improve quality and biological activity of LPS with high yield.

Minimum InDel pattern analysis of the Zika virus

Background

The Zika virus (ZIKV) can cause microcephaly and congenital abnormalities in the foetus. Recent studies have provided insights into the evolution of ZIKV from the current and previous outbreaks, but the types have not been determined.

Results

We analysed the insertions and deletions (InDels) in 212 ZIKV polyproteins and 5 Dengue virus (DENV) reference sequences. Spearman correlation tests for the minimum InDel (minInDel) patterns were used to assess the type of polyprotein. Using the minInDel frequencies calculated from polyproteins with 11 elements, likelihood estimation was conducted to correct the evolutionary distance. The minInDel-corrected tree topology clearly distinguished between the ZIKV types (I and II) with a unique minInDel character in the E protein. From the 10-year average genetic distance, the African and Asian lineages of ZIKV-II were estimated to have occurred ~ 270 years ago, which is unlikely for ZIKV-I.

Conclusions

The minInDel pattern analysis showed that the minInDel in the E protein is targetable for the rapid detection and determination of the virus types.

Electronic supplementary material

The online version of this article (10.1186/s12864-018-4935-z) contains supplementary material, which is available to authorized users.

How Could Private Healthcare Better Contribute to Healthcare Coverage in Vietnam?

Private healthcare services in Vietnam are seen as a major part of the solution to the rapid increase in need and demand for healthcare services. Formally recognized over 20 years ago, the private health services coexist with public services and are available all over the country. However, the scale and size of private sector is still small compared to the public sector and public acceptance and reputation still limited. There are substantial concerns with the quality of services and the adequacy of regulation. Human resource for health is currently inadequate to support growth in both public and private sectors. The role of the private sector in achieving Vietnam’s population health objectives is not clear. In this emerging economy, there is significant potential for increased dependency on private healthcare to increase health access inequities. This paper discusses how private healthcare could better contribute to healthcare coverage in Vietnam.

Biological Characterization of a Stable Effector Functionless (SEFL) Monoclonal Antibody Scaffold in Vitro

The stable effector functionLess (SEFL) antibody was designed as an IgG1 antibody with a constant region that lacks the ability to interact with Fcγ receptors. The engineering and stability and pharmacokinetic assessments of the SEFL scaffold is described in the accompanying article (Jacobsen, F. W., Stevenson, R., Li, C., Salimi-Moosavi, H., Liu, L., Wen, J., Luo, Q., Daris, K., Buck, L., Miller, S., Ho, S-Y., Wang, W., Chen, Q., Walker, K., Wypych, J., Narhi, L., and Gunasekaran, K. (2017) J. Biol. Chem 292). The biological properties of these SEFL antibodies were assessed in a variety of human and cynomolgus monkey in vitro assays. Binding of parent molecules and their SEFL variants to human and cynomolgus monkey FcγRs were evaluated using flow cytometry-based binding assays. The SEFL variants tested showed decreased binding affinity to human and cynomolgus FcγRs compared with the wild-type IgG1 antibody. In addition, SEFL variants demonstrated no antibody-dependent cell-mediated cytotoxicity in vitro against Daudi cells with cynomolgus monkey peripheral blood mononuclear cells, and had minimal complement-dependent cytotoxicity activity similar to that of the negative control IgG2 in a CD20⁺ human Raji lymphoma cell line. SEFL mutations eliminated off-target antibody-dependent monocyte phagocytosis of cynomolgus monkey platelets, and cynomolgus platelet activation in vitro These experiments demonstrate that the SEFL modifications successfully eliminated Fc-associated effector binding and functions.

Contribution of health workforce to health outcomes: empirical evidence from Vietnam

BACKGROUND

In Vietnam, a lower-middle income country, while the overall skill- and knowledge-based quality of health workforce is improving, health workers are disproportionately distributed across different economic regions. A similar trend appears to be in relation to health outcomes between those regions. It is unclear, however, whether there is any relationship between the distribution of health workers and the achievement of health outcomes in the context of Vietnam. This study examines the statistical relationship between the availability of health workers and health outcomes across the different economic regions in Vietnam.

METHODS

We constructed a panel data of six economic regions covering 8 years (2006-2013) and used principal components analysis regressions to estimate the impact of health workforce on health outcomes. The dependent variables representing the outcomes included life expectancy at birth, infant mortality, and under-five mortality rates. Besides the health workforce as our target explanatory variable, we also controlled for key demographic factors including regional income per capita, poverty rate, illiteracy rate, and population density.

RESULTS

The numbers of doctors, nurses, midwives, and pharmacists have been rising in the country over the last decade. However, there are notable differences across the different categories. For example, while the numbers of nurses increased considerably between 2006 and 2013, the number of pharmacists slightly decreased between 2011 and 2013. We found statistically significant evidence of the impact of density of doctors, nurses, midwives, and pharmacists on improvement to life expectancy and reduction of infant and under-five mortality rates.

CONCLUSIONS

Availability of different categories of health workforce can positively contribute to improvements in health outcomes and ultimately extend the life expectancy of populations. Therefore, increasing investment into more equitable distribution of four main categories of health workforce (doctors, nurses, midwives, and pharmacists) can be an important strategy for improving health outcomes in Vietnam and other similar contexts. Future interventions will also need to consider an integrated approach, building on the link between the health and the development.

Unexpected Thrombocytopenia and Anemia in Cynomolgus Monkeys Induced by a Therapeutic Human Monoclonal Antibody

Cynomolgus monkeys dosed with a therapeutic monoclonal antibody (mAbY.1) at ≥50 mg/kg had unexpected acute thrombocytopenia (nadir ∼3,000 platelets/µl), sometimes with decreases in red cell mass. Increased activated macrophages, mitotic figures, and erythrophagocytosis were observed in the spleen. Binding of mAbY.1 to cynomolgus peripheral blood cells could not be detected in vitro. mAbY.1 induced phagocytosis of platelets by peripheral blood monocytes from cynomolgus monkeys, but not from humans. mAbs sharing the same constant domain (Fc) sequences, but differing from mAbY.1 in their variable domains, bound competitively to and had similar biological activity against the intended target. None of these antibodies had hematologic liabilities in vitro or in vivo. Neither the F(ab’)2 portion of mAbY.1 nor the F(ab’)2 portion on an aglycosylated Fc (IgG1) framework caused phagocytosis of platelets in vitro. These data suggest that the hematologic effects of mAbY.1 in cynomolgus monkeys likely occurred through an off-target mechanism, shown to be driven by 1 to 3 amino acid differences in the light chain. The hematologic effects made mAbY.1 an unsuitable candidate for further development as a therapeutic agent. This example demonstrates that nonclinical safety studies may be essential for understanding off-target effects of mAbs prior to clinical trials.

H2O2 oxidative damage in cultured oral epithelial cells: the effect of short-term vitamin C exposure

Smoking is the main etiology of oral cancer and generates oxygen free radicals in the oral cavity. Free radicals have been implicated in apoptosis and in DNA damage inducing alteration of the cell cycle. The antioxidant vitamin C (VC) is reported to inhibit damage induced by free radicals. We exposed cultures of normal human oral epithelial cells to hydrogen peroxide (H2O2) in the presence and absence of VC. Generation of hydroxyl radicals was measured by electron paramagnetic resonance (EPR), cell cycle alterations by flow cytometry, cell death by SYTO 11 and morphology by organotypic culture. Human primary cell culture was given four treatments - control, VC alone, H2O2 alone and VC followed by H2O2. Cell cycle analysis indicated cultures treated with H2O2 had fewer cells in G1 phase (26%) and higher number of cells in S phase (44%) compared to the control (G1 70% & S 14%). Cell cycle of 48 hour VC treatment followed by H2O2 was similar to H2O2 alone. SYTO 11 showed 22% cell death when treated with H2O2 alone compared to 9% of normal control. By organotypic culture H2O2 alone induced a two-fold cell proliferation, loss of maturation, nuclear hyperchromatism and nuclear crowding. Our results suggest that H2O2 is capable of altering the cell cycle and morphology of cultured normal human oral epithelial cells. Forty-eight hour exposure to Vitamin C does not prevent the cell cycle changes caused by hydroxyl radicals.

Axolemmal repair requires proteins that mediate synaptic vesicle fusion

A damaged cell membrane is repaired by a seal that restricts entry or exit of molecules and ions to that of the level passing through an undamaged membrane. Seal formation requires elevation of intracellular Ca(2+) and, very likely, protein-mediated fusion of membranes. Ca(2+) also regulates the interaction between synaptotagmin (Syt) and syntaxin (Syx), which is thought to mediate fusion of synaptic vesicles with the axolemma, allowing transmitter release at synapses. To determine whether synaptic proteins have a role in sealing axolemmal damage, we injected squid and crayfish giant axons with an antibody that inhibits squid Syt from binding Ca(2+), or with another antibody that inhibits the Ca(2+)-dependent interaction of squid Syx with the Ca(2+)-binding domain of Syt. Axons injected with antibody to Syt did not seal, as assessed at axonal cut ends by the exclusion of extracellular hydrophilic fluorescent dye using confocal microscopy, and by the decay of extracellular injury current compared to levels measured in uninjured axons using a vibrating probe technique. In contrast, axons injected with either denatured antibody to Syt or preimmune IgG did seal. Similarly, axons injected with antibody to Syx did not seal, but did seal when injected with either denatured antibody to Syx or preimmune IgG. These results indicate an essential involvement of Syt and Syx in the repair (sealing) of severed axons. We suggest that vesicles, which accumulate and interact at the injury site, re-establish axolemmal continuity by Ca(2+)-induced fusions mediated by proteins such as those involved in neurotransmitter release.

Response of human oral epithelial cells to oxidative damage and the effect of vitamin E

Smoking and periodontal inflammation are various conditions with the potential to induce oxidative stress and thus DNA damage in the oral cavity. In cellular defense systems, vitamin E is considered the most powerful lipid-soluble antioxidant. To investigate whether oxygen-free radicals alter normal progression of the cell cycle and whether vitamin E prevents this damage, we exposed cultured normal human oral epithelial cells to hydrogen peroxide (H2O2) in the presence or absence of vitamin E. Two primary cell lines were analyzed for the presence of hydroxyl radical, cell cycle distribution and morphology. Each cell line received five treatments: control, ethanol only, vitamin E only, H2O2 only or vitamin E followed by H2O2. Degradation of hydroxyl radicals was detected by electron paramagnetic resonance analysis, cell cycle by flow cytometry and morphology by organotypic technique. Hydroxyl radicals were generated in H2O2-treated cells at an initial concentration, which decreased over a period of time. Cell cycle analysis showed that H2O2-treated cells differed from normal cells in that the percentage of cells in the G1 phase decreased markedly (34.3 vs. 61.2% in control) and the S phase increased (35.5 vs. 15.6% in control). Organotypic cultures treated with H2O2 demonstrated nuclear hyperchromatism, loss of maturation and prominent nucleoli, features consistent with premalignant epithelial transformation. In conclusion, our data suggest that H2O2 produced hydroxyl radicals and altered the cell cycle. Also, vitamin E may have the potential to reduce oxidative damage caused by hydroxyl radicals.

Estrogen receptor activation function 1 works by binding p160 coactivator proteins

Estrogen receptor-alpha contains two transactivation functions, a weak constitutive activation function (AF-1) and a hormone-dependent activation function (AF-2). AF-2 works by recruiting a large coactivator complex, composed of one or more p160s, CREB-binding protein (CBP)/p300, and P/CAF (p300 and CBP-associated factor), via direct contacts with the p160s. We report here that independent AF-1 activity also requires p160 contacts. Unlike AF-2, which binds signature NR boxes in the center of the p160 molecule, AF-1 binds to sequences near the p160 C terminus. We propose that the ability of AF-1 and AF-2 to interact with separate surfaces of the same coactivator is important for the ability of these transactivation functions to synergize.

Association of serine protease with the rise of intracellular calcium in cytotoxic T lymphocytes

The precise role of the granular enzyme A (granzyme A), a serine protease, in the lytic process of cytotoxic T lymphocytes (CTL) is not clear. We have recently constructed a CTL line transfected with the antisense gene of granzyme A (a-GrA). These a-GrA CTL had lower GrA activity as well as decreased lytic activities, as measured by 51Cr and by DNA degradation assays. Furthermore, at low effector:target ratio (1:8) in prolonged lytic assays, they could not lyse targets as rapidly as the control CTL. When we examined their ability to exocytose BLT (CBZ-L-lys-thiobenzyl)-esterase in the presence of anti-CD3 antibody, the a-GrA CTL exocytosed poorly compared to the parental CTL or control transfectant with a CAT gene. Most strikingly, a-GrA cells could not release intracellular stores of Ca2+ in response to anti-CD3 induction, although the Ca2+ flux was normal when they were stimulated with ionomycin. When the parental CTL was treated with a specific benzyllactam inhibitor of BLT-esterase or N-tosyl-L-phenylalanylchloromethyl ketone, the Ca2+ flux induced by anti-CD3 was also suppressed. We propose that granzyme A is involved in the signal transduction pathway that causes the rise of the intracellular calcium.