Tau filaments are tethered within brain extracellular vesicles in Alzheimer's disease

The abnormal assembly of tau protein in neurons is the pathological hallmark of multiple neurodegenerative diseases, including Alzheimer's disease (AD). In addition, assembled tau associates with extracellular vesicles (EVs) in the central nervous system of patients with AD, which is linked to its clearance and prion-like propagation between neurons. However, the identities of the assembled tau species and the EVs, as well as how they associate, are not known. Here, we combined quantitative mass spectrometry, cryo-electron tomography and single-particle cryo-electron microscopy to study brain EVs from AD patients. We found filaments of truncated tau enclosed within EVs enriched in endo-lysosomal proteins. We observed multiple filament interactions, including with molecules that tethered filaments to the EV limiting membrane, suggesting selective packaging. Our findings will guide studies into the molecular mechanisms of EV-mediated secretion of assembled tau and inform the targeting of EV-associated tau as potential therapeutic and biomarker strategies for AD.

Evolution of the intracranial features of congenital cytomegalovirus on MRI

AIM

To describe the evolution of the intracranial features of congenital cytomegalovirus (cCMV) on magnetic resonance imaging (MRI).

MATERIALS AND METHODS

Sixteen infants with polymerase chain reaction (PCR)-confirmed cCMV who had undergone at least two MRI examinations of the brain were identified. Two paediatric neuroradiologists reviewed the baseline studies retrospectively for intracranial features of cCMV, including white matter signal abnormalities, subependymal cysts, malformations of cortical development, and intracranial calcification. The subsequent MRI studies were then reviewed and directly compared to the baseline examinations.

RESULTS

White matter signal abnormalities were seen on all 16 baseline studies (100%); these persisted on all subsequent examinations but were patchier, more focal, and associated with an interval reduction in white matter volume. Subependymal cysts were present on 11 (69%) of the baseline scans; these almost universally regressed (in 10 of the 11 cases [91%]), with no new cysts appreciable on subsequent imaging. Malformations of cortical development, exclusively in the form of polymicrogyria, were seen in six (38%) patients and persisted, unchanged, on subsequent imaging. Intracranial calcification was seen in a minority of baseline studies (4 [25%]) and remained stable on subsequent scans.

CONCLUSION

Children with cCMV who present later in life without an established or suspected underlying pathology can pose a challenge to the assessing radiologist. The radiological sequelae of cCMV can be non-specific; in some cases, white matter signal abnormalities and focal loss of white matter volume may be the only intracranial features. It is therefore important that radiologists are aware of cCMV as a potential differential for these findings.

Diagnostic analysis of baseline brain MRI features in infants with congenital cytomegalovirus infection: a simplified scoring system

AIM

To characterise the magnetic resonance imaging (MRI) features of infants with congenital cytomegalovirus (CMV) and categorise those into a simplified MRI scoring system.

MATERIALS AND METHODS

Three neuroradiologists reviewed the examinations of 71 infants retrospectively and scored for the presence of a white matter signal abnormality and structural lesion and each MRI was given a score of 0, 1, 2, or 3 for normal, structural abnormality alone, white matter abnormality alone, white matter abnormality plus structural lesion, respectively. Imaging features were outlines according to symptomatology. Chi-square and Spearman's rho were used to test relationships between MRI features and viral loads and MRI score/symptomatic disease respectively. Cohen's Kappa coefficient was used to assess interobserver agreement.

RESULTS

Of the 49 abnormal studies, 40% (n=20) were seen in asymptomatic infants. The commonest finding was white matter signal abnormality, followed by cyst formation and polymicrogyria (86%, n=42; 71%, n=35; and 33%, n=16, respectively). Cysts were significantly positively correlated with white matter abnormalities and polymicrogyria. On the MRI score, 31%, 10%, 15%, and 44% obtained a score of 0, 1, 2, and 3, respectively; the MRI score was positively correlated with log-transformed viral loads. Interobserver agreement for the presence of white matter signal abnormality, cyst formation, malformations of cortical development (MCD), and global MRI score was excellent (k = 0.82, 0.94, 0.96, and 0.86, respectively).

CONCLUSION

Baseline MRI provides information valuable for treatment decisions, especially in "asymptomatic" infants. The simplified scoring system is easier to use, incorporating solely the imaging findings that are anticipated to have an effect on clinical outcome.

COVID-19-Associated Cytotoxic Lesions of the Corpus Callosum

There are very limited published data on the neurologic complications associated with coronavirus disease 2019 (COVID-19) in the pediatric population. Here we present the first 2 pediatric cases of presumed COVID-19 related cytotoxic lesions of the corpus callosum. Similar to reports in adults, these cases suggest that the COVID-19 infection in children may rarely mediate a hyperinflammatory response that can cause CNS pathology. As the pandemic continues further, the presentation of cytotoxic lesions of the corpus callosum should prompt radiologists to consider COVID-19, among other known causes.

Toxicological analysis of aerosols derived from three electronic nicotine delivery systems using normal human bronchial epithelial cells

Electronic nicotine delivery systems (ENDS) are a rapidly growing global market advertised as a safer alternative to combustible cigarettes. However, comprehensive investigations of END aerosol physicochemical and toxicological properties have not been fully explored across brands to assess relative safety. In this study, we evaluated aerosols collected from three ENDS - Juul Fruit Medley (5% nicotine), Logic Power (2.4% nicotine), and Mistic (1.8% nicotine). ENDS aerosols were generated using standard machine puffing regimen and collected with a novel fluoropolymer condensation trap. Triple quadrupole-inductively coupled plasma-mass determined the presence of heavy metals in collected aerosols. The toxicological effects of ENDS aerosols on normal human bronchial epithelial cells (NHBE) were investigated using cellular viability, reactive oxygen species, oxidative stress assays, along with DNA damage assessments using the CometChip©. Results indicated the total metal concentrations within collected ENDS aerosols were higher for Mistic and Logic compared to Juul. Logic Power aerosols elicited higher reactive oxygen species levels than Mistic and Juul in NHBE after 24-h exposure. Similar dose-dependent reductions of cellular viability and total glutathione were found for each exposure. However, Logic and Juul aerosols caused greater single stranded DNA damage compared to Mistic. Our study indicates that regardless of brand, ENDS aerosols are toxic to upper airway epithelial cells and may pose a potential respiratory hazard to occasional and frequent users.

SAT0323 MYOSITIS-SPECIFIC AND MYOSITIS-ASSOCIATED AUTOANTIBODIES IN A LARGE INDIAN COHORT OF INFLAMMATORY MYOSITIS REVEAL NOVEL CLINICO-PHENOTYPIC PATTERNS

Background:

Idiopathic Inflammatory Myositis (IIM) are heterogenous, with distinct autoantibodies reflecting upon possible clinical evolution and outcomes. Ethnicity has major influence on both antibody prevalence patterns as well as phenotypic behaviours linked to them.

Objectives:

Thus we sought prevalence and co-existence of myositis specific autoantibodies (MSAs) and myositis associated autoantibodies (MAAs) and associated clinical characteristics in a large cohort of patients with IIM.

Methods:

Adult patients with a physician diagnosis of IIM as per ACR/EULAR classification criteria were investigated for the presence of MSAs/MAAs by Line immunoassay (G4, Euro-Immune, Lubeck, Germany). Anti-Nuclear Antibody (ANA) was tested by Immunofluorescence assay (IFA), and patterns in various antibody subsets explored. Prevalence and associations of different antibodies were assessed in disease subsets and clinical phenotypes.

Results:

MSA and MAAs were tested in 250 IIM patients (F:M 3.8:1) of median age 37 (25-47) and disease duration 6 (3-17) years. Dermatomyositis (DM) was seen in most patients 83 (33.2%) followed by overlap myositis (OM), juvenile DM, Anti-synthetase syndrome (ASS), polymyositis (PM), and cancer associated myositis (CAM). MSAs/MAAs were found in 148 (59.2%) of patients, of which 95 (64.2%) had an MSA and 53 (35.8%) had MAAs (Fig, 1A). 93 (62.8%) of autoantibody positive patients were positive for a single antibody, and only 2 (0.8%) of total had more than one MSA (Table 1).

Table 1.

Multiple antibodies positive upon testing for MSA and MAA by the LIA

Note: ** PL-7 co-exists with Ku + Pm/Scl, **PL-12 co-exists with Pm/Scl + Ro52, **SRP co-exists with Pm/Scl + Ro52

The most frequently detected MSA was anti-Jo-1 (8%), with a further 9 specificities each found in 0.5–7.0% of patients. Amongst the autoantibody positive patients, 21% (n=53) had isolated MAA positivity, anti-Ro52 (33, 62.3%) being the most common, followed by anti-Pm/Scl (11, 20.8%) and anti-Ku (9, 17.0%) (Fig. 1B).

Figure 1.

A. MSA and MAA in Indian cohort of myositis B. ANA patterns in myositis C. MSA in ANA negative IIM

On ANA, 76.0% (172 of 226) were positive, with speckled being the most common pattern (37%,Fig. 1C). Of those ANA negative (n=54), 61% had either MSA or MAA (Fig 1D). 18 (54.6%) had autoantibodies associated with cytoplasmic patterns suggesting that cytoplasmic ANA may be underreported.

Clinical presentation akin to DM was seen with all MSA except anti-SRP. PM group was heterogenous, and included ASS, OM and necrotizing phenotype (Fig. 2A). On occasion, anti-SRP, anti-Mi-2 and anti-MDA5 presented with clinical phenotype of ASS. (Fig 2A,C). Patients with ARS or anti-SAE were often clinically amyopathic (Figure 2B,C)

Figure 2.

A. Phenotypic associated with various antibody subsets B,C,and D. MSA/MAA in muscle weakness, rash and ILD phenotype. E. Unique feature of eye-lid edema in some patients with MDA-5 positive myositis

ARS were associated with mechanic’s hand (p<0.0001,OR 7.6), ILD (p<0.0001,OR 4.4), and arthritis (p=.002,OR 2.6) though there was no difference between Jo-1 and non-Jo-1 ASS. Anti-MDA-5 associated with fever (p=0.003,OR 12) and weight loss (p=0.008,OR 10.2) and unique phenotype of eye-lid edema in some adults (Figure 2E) and arthritis in children (p=0.01, OR 11.5). Anti-TIF-1ɣ associated with alopecia (p=0.007,OR 5.9) and malignancy (p= <0.0001,OR 34) in adults but not children.

Conclusion:

Myositis autoantibodies are seen in two-thirds IIM and identify distinct clinical subsets as well as unique phenotypes. MSA/MAA are positive in two-thirds of those negative on ANA, adding diagnostic value. MSAs are nearly always mutually exclusive and thus useful as biomarkers for diagnosis.

Acknowledgments:

MSA testing supported by grants from APLAR and Association of Physicians of India.

Disclosure of Interests:

Latika Gupta: None declared, Priyanka Gaur: None declared, Vikas Agarwal: None declared, Rohit Aggarwal Grant/research support from: Pfizer, Genentech, BMS, Mallinckrodt, Consultant of: Pfizer, Genentech, BMS, Mallinckrodt, Bristol Myers-Squibb, octapharma, CSL Behring, AstraZeneca, Corbus, Kezar, Abbvie, Ramnath Misra: None declared

Is it not time for international guidelines to combat congenital cytomegalovirus infection? A review of central nervous system manifestations

Cytomegalovirus (CMV) is the most commonly transmitted virus in utero with a prevalence of up to 1.5%. The infection has potentially debilitating and devastating consequences for the infected fetus, being a leading cause for neurological disability worldwide. Once acquired, it often goes undetected with only an assumed 10% of infected neonates displaying the classic clinical or imaging features. Viral DNA polymerase chain reaction (PCR) of saliva or urine obtained within the first 21 days of life is required to make the diagnosis. As the majority of infected neonates are initially asymptomatic, diagnosis is often delayed. An abnormal routine neonatal hearing test and characteristic antenatal cranial ultrasound imaging findings may raise the suspicion of congenital CMV (cCMV) in the asymptomatic group. Ultimately, the aim is to facilitate early diagnosis and timely treatment. In this article, we highlight diagnostic and treatment challenges of the commonest congenital infection, we present the current available central nervous system imaging severity grading systems, and highlight the need for an internationally agreed diagnostic grading system that can aid treatment decision-making.

AML1 protein interacts with influenza A virus neuraminidase and upregulates IFN-β response in infected mammalian cells

Neuraminidase (NA) is an integral membrane protein of influenza A virus (IAV) and primarily aids in the release of progeny virions, following the intracellular viral replication cycle. In an attempt to discover new functions of NA, we conducted a classical yeast two-hybrid screen and found acute myeloid leukaemia marker 1 (AML1) as a novel interacting partner of IAV-NA. The interaction was further validated by co-immunoprecipitation in IAV-infected cells and in an in vitro coupled transcription/translation system. Interestingly, we found an increase in the expression of AML1 upon IAV infection in a dose-dependent manner. As expected, we also observed an increase in the IFN-β levels, the first line of defence against viral infections. Subsequently, when AML1 was downregulated using siRNA, the IFN-β levels were found to be remarkably reduced. Our study also shows that AML1 is induced upon IAV infection and results in the induction of IFN-β. Thus, AML1 is proposed to be an important player in IFN induction and has a role in an antiviral response against IAV infection. SIGNIFICANCE AND IMPACT OF THE STUDY: Influenza epidemics and pandemics are constant threats to human health. Development of antiviral therapeutics has focused on important and major IAV proteins as targets. However, the rate at which this virus mutates makes the task challenging. Thus, next-generation approaches aim at host cellular proteins that aid the virus in its replication. This study reports a new host-virus interaction, of acute myeloid leukaemia marker 1 (AML1) with influenza A neuraminidase (IAV-NA). We have found that this interaction has a direct effect on the upregulation of host IFN-β response. Further studies may lead to a greater understanding of this new innate defence pathway in infected cells.

Outcomes of Primary Arteriovenous Fistula for Hemodialysis in Elderly Patients (>65 Years) with End Stage Renal Disease: A Study on Indian Population

Introduction:

The outcome of arteriovenous fistula (AVF) for hemodialysis (HD) in elderly population remains an issue. The aim of our study was to evaluate the outcomes of arteriovenous fistulas created at our institute in patients older than 65 years.

Methods:

All chronic HD patients with age >65 years who had an AVF created between January 1, 2010 and January 1, 2017 were included retrospectively. Baseline demographic information including age, gender, etiology of renal failure and comorbidities were recorded. Access characteristics including access type and anatomic location were recorded. The end point of study was primary and secondary patency. Minimum follow up period of study was 1 year.

Results:

A total of 422 AVF were created within the study period. The mean age was 69.3 years. The anatomical site of AVF creation was radiocephalic (RCF) in 74.8% (n = 316), brachiocephalic (BCF) in 18.9% (n = 80) and brachiobasilic (BBF) in 6.1% (n = 26). At one year after creation, cumulative survival of the AVF was 64.7%. At 36 months the primary and secondary patency of RCF, BCF and BBF was 43.6%, 58.6%, 42.6% and 47.3%, 62.5%, 56.9% respectively. The overall median survival did not differ between RCF and BBF fistulas. However, when both were compared with BCF (median survival 1034 days), BBF (median survival 741 days) and RCF (median survival 592 days) had significantly poorer survival (P = 0.004). The most common reason for access failure was thrombosis (28.4%) followed by failure to mature (9%) and aneurysm related complications (9%).

Conclusions:

Age should not be a limiting factor when choosing AVF as the preferred HD access. Brachiocephalic AVF has better primary and secondary patency with higher overall median survival. However RCF also provides reasonably good survival rates with acceptable complications in elderly population. Thrombosis and fistulas that fail to mature present as a primary concern to patients in elderly population, and demand further study.

Effect of probiotics on clinical and immune parameters in enthesitis-related arthritis category of juvenile idiopathic arthritis

Gut microflora and dysbiosis as an environmental factor has been linked to the pathogenesis of enthesitis-related arthritis (JIA-ERA); thus, we performed a proof-of-concept study of probiotics to modulate the gut-flora and study the effects on immune and clinical parameters of children having JIA-ERA. Forty-six children with active JIA-ERA were randomized to placebo or probiotic therapy along with non-steroidal anti-inflammatory drugs (NSAIDs) for 12 weeks. Patients were assessed using a six-point composite disease activity index (mJSpADA) based on morning stiffness, joint count, enthesitis count, sacroiliitis/inflammatory back pain, uveitis and erythrocyte sedimentation rate/C-reactive protein (ESR/CRP). Frequencies of T helper type 1 (Th1), Th2, Th17 and regulatory T cells in blood were measured using flow cytometry. Serum cytokines interferon (IFN)-γ, interleukin (IL)-4, IL-17, IL-10, tumour necrosis factor (TNF)-α and IL-6 were measured by cytokine bead array using flow cytometer. The average age of 46 children (44 boys) was 15 ± 2.5 years and duration of disease was 3.5 ± 3 years. There was no significant difference in improvement in mJSpADA between the two groups (P = 0·16). Serum IL-6 levels showed a decrease (P < 0·05) in the probiotic-group. Th2 cell frequency (P < 0·05) and serum IL-10 levels (P < 0·01) showed an increase in the placebo group, but again the probiotic use did not show a significant change in immune parameters when compared to the placebo. Adverse effects among the probiotic and placebo groups were diarrhea (36 versus 45%), abdominal pain (9 versus 20%), minor infections (4·5 versus 20%) and flatulence (23 versus 15%), respectively. Thus, we can conclude that probiotic therapy in JIA-ERA children is well tolerated, but failed to show any significant immune or clinical effects over NSAID therapy.

Gut microbiome in children with enthesitis-related arthritis in a developing country and the effect of probiotic administration

In Asia, enthesitis-related arthritis (ERA) is the most frequent category of juvenile idiopathic arthritis. ERA has a strong association with human leucocyte antigen (HLA)-B27 and subclinical gut inflammation. In an HLA-B27 transgenic rat model, the presence of Bacteroides bacteria in the gut appears to cause spondyloarthropathy (SpA). Thus, we studied gut microbiota in children with ERA. Stool specimens from 33 patients with ERA and 14 age-matched healthy controls were studied; none had any gastrointestinal symptom, or had received a drug known to affect gut motility or microbiota in the preceding 6 weeks. From each specimen, a cDNA library for the V3 region of bacterial 16S rRNA was subjected to high-throughput, massively parallel sequencing. Relationship of the specimens was studied using principal co-ordinate analysis (PCoA), and abundances of various bacterial taxa and alpha diversity were compared between groups. In eight patients, a repeat faecal specimen was studied after 12 weeks of probiotic therapy. The 55 specimens yielded a median (range) of 397 315 (102 093-1 502 380) high-quality reads each. In PCoA, gut microbiota from ERA showed a wider dispersion than those from controls. In patients, families Bacteroidaceae and Enterobacteriaceae were more abundant and Prevotellaceae were less abundant than in controls. Also, genera Bacteroides, Entercoccus and Klebsiella were over-represented and genus Prevotella was under-represented in ERA patients. Probiotic therapy led to a non-significant increase in Prevotellaceae. Patients with ERA have a dysbiosis in the gut, with increased abundance of Bacteroides and reduction of Prevotella. Probiotic supplementation in a subset of patients did not reverse these changes significantly.

Intermediate monocytes are increased in enthesitis-related arthritis, a category of juvenile idiopathic arthritis

Microarray of peripheral blood (PB) and synovial fluid mononuclear cells (PBMC, SFMC) of patients with juvenile idiopathic arthritis-enthesitis-related arthritis (JIA-ERA) has shown the involvement of monocytes. On the basis of CD14 and CD16 expression, monocytes are classified as classical, intermediate and non-classical. In response to Toll-like receptor (TLR) stimulation, intermediate monocytes produce proinflammatory cytokines and play a role in inflammatory diseases. Therefore, we have studied the microarray profile of monocytes, the frequency of their subsets and cytokine production. Monocyte-specific microarray analysis was performed in six healthy controls' PBMC and six patients' PBMC and SFMC using Illumina chips WG12. Monocyte subsets were assessed in 46 patients with JIA-ERA and 17 healthy controls and 17 disease controls by flow cytometry. Interleukin (IL)-23 and tumour necrosis factor (TNF) levels were measured in culture supernatants of eight controls and seven patients' PBMC/SFMC with/without lipopolysaccharide (LPS) stimulation. Cytokine-producing intermediate monocytes were assessed by flow cytometry. Genes related to antigen presentation, cytokine signalling and TLR pathway were regulated differentially in PB and synovial monocytes of patients with JIA-ERA. Key genes of intermediate monocytes, such as CLEC10A and MARCO, were expressed three- to fourfold more in JIA-ERA. In PB, the frequency of intermediate monocytes was significantly higher in JIA-ERA (4·90% ± 3·5) compared to controls (1·8% ± 1·06; P < 0·001). Patients' synovial cells also had more intermediate monocytes compared to PB (11·25% ± 11·32, 5·9% ± 4·8; P = 0.004). Intermediate monocytes are the major producers of IL-23. Thus, intermediate monocytes may play an important role in JIA-ERA, possibly by producing cytokines, and contribute to joint inflammation.

First high quality draft genome sequence of a plant growth promoting and cold active enzyme producing psychrotrophic Arthrobacter agilis strain L77

Arthrobacter agilis strain L77, is a plant growth promoting and cold active hydrolytic enzymes producing psychrotrophic bacterium, isolated from Pangong Lake, a subglacial lake in north western Himalayas, India. Genome analysis revealed metabolic versatility with genes involved in metabolism and cold shock adaptation, utilization and biosynthesis of diverse structural and storage polysaccharides such as plant based carbon polymers. The genome of Arthrobacter agilis strain L77 consists of 3,608,439 bp (3.60 Mb) of a circular chromosome. The genome comprises of 3316 protein coding genes and 74 RNA genes, 725 hypothetical proteins, 25 pseudo-genes and 1404 unique genes.

Cadaveric feasibility study on the use of ultrasound contrast to assess spread of injectate in the serratus anterior muscle plane

BACKGROUND

The Serratus anterior muscle plane (SAP) block has recently been described for the purpose of perioperative pain management following cases of trauma and breast surgery. It might prove a safer alternative to the other regional thoracic paravertebral and central neuraxial blockade techniques. There are no descriptive cadaveric studies in the pre-existing literature to delineate the anatomical plane for this novel technique. The main objectives for our study were to examine the location of the Serratus anterior muscle belly, assess the efficacy of achieving adequate delineation of the muscle plane utilising ultrasound imaging with agitated water as the contrast agent, and finally, to observe the extent of the cepahlo-caudal spread of the injectate in the SAP.

MATERIALS AND METHODS

Seven cadavers were studied. 20 mls of saline was injected into posterior axillary line (PAL) at the level of the 4-5(th) rib under ultrasound guidance. This was followed by injection of 10 mls of water with air (8 mls water and 2 mls of air). The presence of hyperechoic air bubbles in the fluid distended SAP (hypoechoic) area demonstrated the spread of water and air.

RESULTS

In 36% of cadavers, fully formed Serratus Anterior muscle belly was identified at the midaxillary line (MAL), 14% in PAL, and remaining 50% between PAL and MAL. The lower most limit of air-water spread was identified at the subcostal margin. Cephalad spread of contrast was noted in 2(nd) intercostal space ICS (7%), 3(rd) ICS (71%), and 4(th) ICS (22%).

CONCLUSION

This study describes that the serratus anterior muscle is well-formed near the PAL and the injectate spread can be determined with the help of agitated water contrast on ultrasound. Furthermore, there was variability in the cephalad spread of the injectate.

Urinary osteoprotegerin: a potential biomarker of lupus nephritis disease activity

OBJECTIVES

Urinary biomarkers may help in identification, treatment and assessment of response in patients with lupus nephritis (LN). Osteoprotegerin (OPG) is produced by the kidneys and lymphoid cells and may reflect renal disease activity better. The data on its utility are sparse.

METHODS

Fifty-eight patients with active LN (AN), 24 with active non-renal disease (ANR) and 39 with inactive disease (ID) were included. Median disease duration was 32 (1-204) months and median age was 27 (12-50) years. AN patients were followed up every three months for one year. Urine and serum samples were collected for OPG measurement by ELISA (pg/ml) and urinary values were normalised for creatinine excretion (pg/mg). Urine samples from 24 healthy individuals (HCs) and 20 patients each of rheumatoid arthritis (RA) and diabetic nephropathy (DM) served as controls. Variables were expressed as median (range).

RESULTS

At baseline, normalised urinary OPG (uOPG) was significantly higher (p < 0.001) in AN (1229 (0-8577)) than ANR (236 (0-14713)), ID (463 (7-4253)), HCs (366 (120-2849)) and DM (350 (127-1577)) but it was not different from RA (1511 (122-8849)). uOPG correlated modestly with rSLEDAI (r = 0.4, p < 0.001) and SLEDAI (r = 0.31, p < 0.001) but not with serum OPG (sOPG). uOPG but not sOPG could differentiate between AN and ANR groups. In the longitudinal study, uOPG and sOPG decreased significantly with treatment at all follow-up visits but the trend of fall in sOPG was erratic. uOPG values at baseline, 3, 6, 9 and 12 months were 1229 (0-8577), 466 (3-4874), 104 (0-1598), 325 (0-4025) and 555 (6-6771) pg/mg, respectively. uOPG but not sOPG rose before conventional markers in three patients who had a relapse of LN. In two patients who developed chronic kidney disease, uOPG remained persistently high. For differentiating AN from ANR patients, uOPG performed the best on receiver operator characteristics analysis (AUC = 0.72) when compared with anti-dsDNA antibodies, C3, C4 and sOPG.

CONCLUSION

uOPG is derived from kidneys and helps differentiate active SLE patients with and without LN. It shows modest correlation with disease activity and has a potential to predict poor response to therapy and relapse of LN.

Proliferation Index Predicts Survival after Second Craniotomy within 6 Months of Adjuvant Radiotherapy for High-grade Glioma

AIMS

To determine pathological features that predict survival in patients having repeat craniotomy within 6 months of radiotherapy for high-grade glioma (HGG).

MATERIALS AND METHODS

HGG patients (World Health Organization grade 3/4) managed with repeat craniotomy within 6 months of completing radiotherapy between 2008 and 2012 were included. Based on the presence of residual tumour cells, the pathology was reported as pathological progression or pathological pseudoprogression. The proliferation index (Ki67) was reported and compared with initial pathology as a percentage change. Tumour necrosis was estimated as a percentage of the specimen. Overall survival was calculated in months.

RESULTS

Of 327 patients managed with HGG, 27 patients underwent repeat craniotomy within 6 months of radiotherapy. The median survival after reoperation was 11 months (95% confidence interval 1-22). Ki67 at reoperation of 0%, 1-9% and >10% was associated with survival with a median survival of 13, 13 and 3 months, respectively (P = 0.007). Change in Ki67 was also associated with median survival, with <50% reduction median survival 3 months, 50-80% median survival 7 months and >80% reduction median survival 13 months, P = 0.02. Widespread treatment-related necrosis improved outcome, with >80% necrosis having a median survival of 13 months versus 3 months in those with <80% necrosis (P = 0.003).

CONCLUSION

The presence of residual tumour at repeat craniotomy within 6 months of radiotherapy is not an independent indicator of prognosis. Patients with residual tumour that had a low Ki67 had a similar median survival as those with only treatment necrosis. Reduced proliferation of residual tumour cells and widespread necrosis may be more important indicators for future outcome.

Biodegradation of pyrene and phenanthrene by bacterial consortium and evaluation of role of surfactant

High molecular weight poly aromatic hydrocarbons (HMW PAHs) are well known for their hydrophobicity and they get strongly adsorbed onto the soil particles. Generally, surfactants facilitate the biodegradation of PAH by enhancing their solubility and desorption of hydrophobic compounds from soil particles. To investigate the role of synthetic surfactant in biodegradation of PAHs, two bacterial strains BP10 and P2 were incubated in soil spiked with pyrene and phenantherene (100 μg g-1of soil each) in isolation and in combination with/without Tween 80. After 14 days of incubation, pyrene and phenantherene were degraded by a combination of BP10 and P2 to the extent of 98% and 99%, respectively. Addition of tween 80 reduced the degradation of pyrene and phenantherene by 35 and 10%, respectively. Biosurfactant produced by selected strains i.e. BP10 and P2 could enhance desorption of pyrene (100 μg g-1of soil) by about 27% and 12%, respectively. However, desorption activity was relatively higher (32 and 29%, respectively) in case of phenanthrene (100 μg g-1of soil) from the spiked soil. Present study showed that in spite of additional chemical surfactant, bioaugmentation of highly petroleum hydrocarbon degrading bacterial combination was very effective in boosting the bioremediation of PAHs- contaminated sites.

Should we continue to drain the pylorus in patients undergoing an esophagectomy?

A systematic review of the literature was performed to assess the necessity of a pyloric drainage procedure during an esophagectomy with gastric conduit reconstruction. Earlier data recommend performing a pyloric drainage procedure for all esophagectomies; however, recent studies have questioned this. A thorough literature search (January 2001-November 2011) was performed using the terms esophagectomy, pyloroplasty, pyloromyotomy, botulinum toxin, and pyloric drainage. Only studies that compared patient outcome after undergoing an esophagectomy with a pyloric drainage procedure with those undergoing an esophagectomy without a pyloric drainage procedure were selected. Only four studies, comprising 668 patients in total, were identified that compared patient outcome after undergoing an esophagectomy with or without a pyloric drainage procedure, and two additional meta-analyses were identified and selected for discussion. All studies were retrospective, and because of the heterogeneity of studies, patient demographics, reporting, and statistical analysis of patient outcome, pooling of data and meta-analysis could not be performed. Careful analysis demonstrated that pyloric drainage procedure was associated with a non-significant trend for delayed gastric emptying and biliary reflux, while not affecting the incidence of dumping. No correlation was determined between a pyloric drainage procedure and anastomotic leaks, postoperative pulmonary complications, length of hospital stay, and overall perioperative morbidity. While there are risks associated with a pyloric drainage procedure and data exist supporting its omission during an esophagectomy, no good conclusion can be drawn from the current literature. Larger multi-institutional, prospective studies are required to definitively answer this question.

A draft of the genome and four transcriptomes of a medicinal and pesticidal angiosperm Azadirachta indica

Background

The Azadirachta indica (neem) tree is a source of a wide number of natural products, including the potent biopesticide azadirachtin. In spite of its widespread applications in agriculture and medicine, the molecular aspects of the biosynthesis of neem terpenoids remain largely unexplored. The current report describes the draft genome and four transcriptomes of A. indica and attempts to contextualise the sequence information in terms of its molecular phylogeny, transcript expression and terpenoid biosynthesis pathways. A. indica is the first member of the family Meliaceae to be sequenced using next generation sequencing approach.

Results

The genome and transcriptomes of A. indica were sequenced using multiple sequencing platforms and libraries. The A. indica genome is AT-rich, bears few repetitive DNA elements and comprises about 20,000 genes. The molecular phylogenetic analyses grouped A. indica together with Citrus sinensis from the Rutaceae family validating its conventional taxonomic classification. Comparative transcript expression analysis showed either exclusive or enhanced expression of known genes involved in neem terpenoid biosynthesis pathways compared to other sequenced angiosperms. Genome and transcriptome analyses in A. indica led to the identification of repeat elements, nucleotide composition and expression profiles of genes in various organs.

Conclusions

This study on A. indica genome and transcriptomes will provide a model for characterization of metabolic pathways involved in synthesis of bioactive compounds, comparative evolutionary studies among various Meliaceae family members and help annotate their genomes. A better understanding of molecular pathways involved in the azadirachtin synthesis in A. indica will pave ways for bulk production of environment friendly biopesticides.

Chemoresistant colorectal cancer cells and cancer stem cells mediate growth and survival of bystander cells

BACKGROUND

Recent studies suggest that cancer stem cells (CSCs) mediate chemoresistance, but interestingly, only a small percentage of cells in a resistant tumour are CSCs; this suggests that non-CSCs survive by other means. We hypothesised that chemoresistant colorectal cancer (CRC) cells generate soluble factors that enhance survival of chemonaive tumour cells.

METHODS

Chemoresistant CRC cells were generated by serial passage in oxaliplatin (Ox cells). Conditioned media (CM) was collected from parental and oxaliplatin-resistant (OxR) cells. CRC cells were treated with CM and growth and survival were assessed. Tumour growth rates were determined in nude mice after cells were treated with CM. Mass spectrometry (MS) identified proteins in CM. Reverse phase protein microarray assays determined signalling effects of CM in parental cells.

RESULTS

Oxaliplatin-resistant CM increased survival of chemo-naive cells. CSC CM also increased growth of parental cells. Parental and OxR mixed tumours grew larger than tumours composed of parental or OxR cells alone. Mass spectrometry detected unique survival-promoting factors in OxR CM compared with parental CM. Cells treated with OxR CM demonstrated early phosphorylation of EGFR and MEK1, with later upregulation of total Akt .We identified progranulin as a potential mediator of chemoresistance.

CONCLUSION

Chemoresistant tumour cells and CSCs may promote resistance through soluble factors that mediate survival in otherwise chemosensitive tumour cells.

Functional variants of IL4 and IL6 genes and risk of tobacco-related oral carcinoma in high-risk Asian Indians

BACKGROUND

Tobacco-related oral squamous cell carcinoma (OSCC) is one of the most common cancers involving Indian males. We assessed the association of IL4 promoter -589 T>C, -33 T>C, and IL6-174 G>C functional genetic polymorphisms with tobacco-related OSCC in Asian Indians.

PATIENTS AND METHODS

The IL4 and IL6 promoter polymorphisms were assessed in 140 patients with OSCC and 120 normal subjects by PCR-RFLP technique, and significance of the data was determined using chi-square test.

RESULTS

The frequency of TC, CC genotype, and C allele at IL4 promoter sites -589 and -33 were higher in patients when compared with controls. Consequently, TC/CC genotypes and C allele at both sites appeared as susceptible. However, IL6-174 G>C single-nucleotide polymorphisms (SNP) appeared to be protective in patients with OSCC. Of eight haplotypes, five were associated with two- to seven-fold increased risk of tobacco-related OSCC. These SNPs further showed heterogeneity among different ethnic population, but their distribution in Asian Indians stand closer to other Asian populations.

CONCLUSIONS

In this study, IL4-589 CC, -33 CC genotype, and *C allele at both sites appeared to be susceptible, while IL6-174 CC genotype and *C allele appeared to be protective in patients with OSCC; hence, these SNPs may be a potential prognostic markers for tobacco-related OSCC in Asian Indians.

Chronic exposure of colorectal cancer cells to bevacizumab promotes compensatory pathways that mediate tumour cell migration

BACKGROUND

Bevacizumab (Bev), a monoclonal antibody to vascular endothelial growth factor (VEGF), is used in combination with chemotherapy for the treatment of metastatic colorectal cancer (CRC). The effects of Bev on angiogenesis have been well described, but the direct effect of Bev on tumour cells is unknown. This study was carried out to determine the molecular and phenotypic changes in CRC cells after chronic Bev exposure in vitro.

METHODS

Human CRC cell lines were chronically exposed (3 months) to Bev in vitro to develop Bev-adapted (Bev-A) cell lines. Vascular endothelial growth factor family members were determined by reverse transcription-polymerase chain reaction and western blotting. Migration and invasion was determined using standard in vitro assays. Intravenous injection of tumour cells was carried out to evaluate metastatic potential in mice.

RESULTS

Bevacizumab-adapted cells were found to be more migratory and invasive than control cells (P<0.001). Bevacizumab-adapted cells showed higher levels of VEGF-A, -B, -C, placental growth factor (PlGF), VEGF receptor-1 (VEGFR-1) and phosphorylation of VEGFR-1. Furthermore, treatment with SU5416, a VEGFR protein tyrosine kinase inhibitor, led to significantly decreased cell migration in vitro (P<0.001). Bevacizumab-adapted cells were more metastatic in vivo (P<0.05).

CONCLUSION

Chronic exposure of CRC cells to Bev (1) increased expression of VEGF-A, -B, -C, PlGF, VEGFR-1 and VEGFR-1 phosphorylation, (2) increased tumour cell migration and invasion, and (3) metastatic potential in vivo. Our study shows the functional significance of autocrine VEGF signalling in CRC cells.

Therapeutic targeting of Id2 reduces growth of human colorectal carcinoma in the murine liver

During development inhibitor of DNA-bind-2 (Id2) regulates proliferation and differentiation. Id2 expression has been detected in cancer cells, yet its cellular function and validity as a therapeutic target remains largely unknown. Immunohistochemical analysis of colorectal cancer (CRC) specimens revealed that Id2 was undetectable in normal colonic mucosa, but occurs in 40% of primary tumors and in most CRC liver metastases (P<0.0001). Additionally, Id2 was expressed in all CRC cell lines assayed. CRC cells with reduced Id2 expression demonstrated reduced proliferation. Analysis of CRC cell cycle regulatory proteins showed that reducing Id2 levels reduces cyclin D1 levels and increased p21 levels. Reduction of Id2 expression also enhanced tumor cell apoptosis, increasing levels of the pro-apoptotic protein Bim/Bod, and cleavage of caspase-7 and poly (ADP-ribose) polymerase. In vivo studies show tumors derived from cells with decreased Id2 levels formed smaller tumors with fewer metastases compared with tumors with normal levels (P<0.05). Furthermore, intraperitoneal administration of Id2 small interfering RNA (siRNA) conjugated with the neutral liposome 1,2-dioleoyl-sn-glycero-3-phosphatidylcholine decreased tumor burden in mice compared with control treatment (P=0.006). We conclude that Id2 is upregulated in CRC, and is important in promoting cell survival. In vivo targeting of Id2 by siRNA establishes that it is a valid therapeutic target where its expression occurs.

Functional MRI of sentence comprehension in children with dyslexia: beyond word recognition

Sentence comprehension (SC) studies in typical and impaired readers suggest that reading for meaning involves more extensive brain activation than reading isolated words. Thus far, no reading disability/dyslexia (RD) studies have directly controlled for the word recognition (WR) components of SC tasks, which is central for understanding comprehension processes beyond WR. This experiment compared SC to WR in 29, 9-14 year olds (15 typical and 14 impaired readers). The SC-WR contrast for each group showed activation in left inferior frontal and extrastriate regions, but the RD group showed significantly more activation than Controls in areas associated with linguistic processing (left middle/superior temporal gyri), and attention and response selection (bilateral insula, right cingulate gyrus, right superior frontal gyrus, and right parietal lobe). Further analyses revealed this overactivation was driven by the RD group's response to incongruous sentences. Correlations with out-of-scanner measures showed that better word- and text-level reading fluency was associated with greater left occipitotemporal activation, whereas worse performance on WR, fluency, and comprehension (reading and oral) were associated with greater right hemisphere activation in a variety of areas, including supramarginal and superior temporal gyri. Results provide initial foundations for understanding the neurobiological correlates of higher-level processes associated with reading comprehension.

Serum levels of cancer-associated antigen CA-195 in gastrointestinal cancers and its comparison with CA19-9

The antibody against CA-195 binds to an epitope that consists of both Lewis A and sialylated Lewis A blood group antigen, whereas CA19-9 has shown specificity for sialylated Lewis A blood group antigen. CA19-9 and CA-195 levels were measured in the sera of 52 normal subjects; 65 benign disease patients; and 74 non-gastrointestinal, 149 colorectal, and 119 upper gastrointestinal cancer patients to correlate their levels with disease status of the patients. Low incidence and levels were found among normal subjects for both markers; however, in the benign disease group a slightly higher incidence of elevation was seen for CA19-9. Among colorectal cancer patients CA-195 appeared to show higher sensitivity for primary as well as advanced disease. Levels of both markers showed similar incidences of elevation among upper gastrointestinal cancer patients. Based on these results the contribution of Lea specificity of CA-195 cannot be ruled out, and it may be used alone or in combination with other markers for monitoring of patients with colorectal, pancreatic, gastric, gall bladder, bile duct, and liver cancers.