Dose to Organ at Risk and its Characteristic Variation with the Clinically Used Different Prescription Levels for Early-stage Left-sided Breast Cancer

AIMS

To evaluate the organ at risk (OAR) dose and its characteristic variation with different clinically usable prescription doses (RxD) for breast and chest wall radiotherapy in patients with early-stage left-sided breast cancer.

MATERIALS AND METHODS

In total, 145 patients with early-stage breast cancers (T1N0M0-T2N0M0) on the left side were treated with radiotherapy after a modified radical mastectomy or breast conservation surgery, with a mean age of 45.1 ± 21.6 years. The patient received 4050 cGy of field-in-field (three-dimensional conformal radiotherapy) treatment limited to the breast or chest wall, excluding the supraclavicular node, axillary node and internal mammary chain, over 15 fractions. Additional plans of 5000 cGy/25 fractions, 4500 cGy/20 fractions and 2600 cGy/5 fractions were created with no or minor changes to the original plan. Mathematical modelling was used to study the distinctive change in the dose-volume characteristics for various OARs as a function of the RxD. OAR dosages, both absolute and normalised, were expressed in terms of the RxD. The mathematical (functional) relationship between OAR doses and different prescription levels was deduced by the least squares fit method.

RESULT

The left lung mean dose, V5Gy (%), V10Gy (%) and V20Gy (%) and the heart mean dose, V10Gy (%) and V20Gy (%) were evaluated. The dose-volume parameters showed a parabolic variation (x2) with the RxD. Prescription normalised OAR doses showed a linear relationship with the RxD; relative dose increased with diminishing RxD. Normalised lung and heart mean doses exhibited saturation (linear relationship) with RxD variation. Paired sample t-test results between RxD versus all evaluated parameters were found to be statistically significant (P = 0.004). The Pearson correlation coefficient between different prescription levels for left lung mean dose (range 0.942-1.0), heart mean dose (range 1.0-1.0), left lung V5Gy (%) (range 0.987-1.0), left lung V10Gy (%) (range 0.991-0.999), heart V10Gy (%) (range 0.998-1.0).

CONCLUSION

The functional form of absolute OAR dose-volume parameters versus RxD is parabolic and the RxD normalised OAR dose-volume parameter versus RxD is a straight line with a negative slope as RxD increases. This indicates an increase in the relative OAR dose-volume parameters if the RxD is reduced. This study is the first of its kind to compare the OAR doses as a function of clinically used degenerate prescription levels. These data will help to comprehend the OAR doses while adopting a new dose fractionation regimen and reviewing the radiotherapy treatment plans.

Abstract PR007: Comprehensive ctDNA profiling reveals potential metastatic genomic signatures in treatment-naive early-stage breast cancer patients

Background: Genomic profiling has revolutionized precision oncology impacting the diagnosis, prognosis, and therapy decisions. Considering high spatiotemporal diversity and heterogenicity of breast tumor-cell genomes, small-gene panels often fail to capture rare but important genomic alterations. Conversely, comprehensive ctDNA sequencing approaches enable the identification of under characterized ‘long tailed driver’ genomic alterations and capture Intra and inter metastatic heterogeneity. Here, we demonstrate the clinical utility of comprehensive genome profiling with higher sensitivity to predict the possibility of metastasis in early-stage breast cancer patients. Methods: We retrospectively analyzed ctDNA and genomic DNA (gDNA) from FFPE samples as well as circulating tumor cells (CTC) in 10 treatment-naive hormone positive and HER2 negative, primary-stage breast cancer patients [GS1] using the OncoIndx comprehensive 600 gene panel. The panel captures all important cancer-relevant genomic alterations including Tumor Mutation Burden (TMB), Micro Satellite Instability (MSI), homologous recombination deficiency (HRD) prediction, and cfDNA tumor fraction (TF). CTCs were enumerated from 1.5 ml of blood using the OncoDiscover platform approved by the Drug Controller General of India having anti-EpCAM antibody-mediated immunomagnetic nanoparticles. CTCs were confirmed for cytokeratin 18+ and DAPI + markers and the absence of CD45. Results: Comprehensive genomic profile obtained from ctDNA and gDNA from FFPE of early-stage breast cancer patients predominantly exhibited the presence of alterations in PIK3CA and ESR1 signaling pathways. PIK3CA mutations were present in 77% and 44% of baseline ctDNA and gDNA samples, while ESR1 mutations were present in 44% and 22% of baseline ctDNA and gDNA, respectively. In addition, we observed about 70% additional driver mutations in ctDNA samples suggesting shedding of ctDNA together with CTC (80% positive), a likely positive biomarker of metastasis. About 50% of the patients showed higher TMB and HRD. Notably, TF representing ctDNA varied between 13% to 27% in blood samples with a corresponding ploidy range of 2.9 to 4.7. Surprisingly, ~50% of the patient population matched the mutation profile of clinically confirmed metastatic patients. All the patients harboring potential metastatic driver alterations showed the presence of CTCs in peripheral blood. Conclusions: Comprehensive ctDNA genomic profiling showed potential metastasis driving alterations suggesting the role of ctDNA-based liquid biopsy to predict metastasis in early breast cancer patients. We observed enhanced TF at the time of diagnosis, possibly due to the presence of distant metastasis, high disease burden, and aggressive tumor biology. Our results suggest that ctDNA dynamics at the time of disease presentation can predict early metastasis, and may demonstrate the divergent response of tumor heterogeneity to treatment in early-stage breast cancer.

Citation Format: Gowhar Shafi, Manoj Dongare, Atul Bharde, Moubeen Fauzul, Kanchan Hariramani, Alain D’Souza, Bhagwat Jadhav, Trupti Kad, Sangeeta Prajapati, Vikas Jadhav, ManojKumar Kumaran, Sumit Haldar, Vatsal Mehra, Sujit Joshi, Gourishankar Aland, Richa Dave, Sreeja Jayant, Aravindan Vasudevan, Mohan Uttarwar, Jayant Khandare. Comprehensive ctDNA profiling reveals potential metastatic genomic signatures in treatment-naive early-stage breast cancer patients [abstract]. In: Proceedings of the AACR Special Conference: Cancer Metastasis; 2022 Nov 14-17; Portland, OR. Philadelphia (PA): AACR; Cancer Res 2022;83(2 Suppl_2):Abstract nr PR007.

Machine learning approach to study quantum phase transitions of a frustrated one dimensional spin-1/2 system

Frustration-driven quantum fluctuation leads to many exotic phases in the ground state (GS) and the study of these quantum phase transitions is one of the most challenging areas of research in condensed matter physics. We study a frustrated HeisenbergJ1-J2model of spin-1/2 chain with nearest exchange interactionJ₁and next nearest exchange interactionJ₂using the principal component analysis (PCA) which is an unsupervised machine learning technique. In this method most probable spin configurations (MPSCs) of GS and first excited state (FES) for differentJ2/J1are used as the input in PCA to construct the covariance matrix. The 'quantified principal component'p1(J2/J1)of the largest eigenvalue of the covariance matrix is calculated and it is shown that the nature and variation ofp1(J2/J1)can accurately predict the phase transitions and degeneracies in the GS. Thep1(J2/J1)calculated from the MPSC of GS only exhibits the signature of degeneracies in the GS, whereas,p1(J2/J1)calculated from the MPSC of FES captures the gapless spin liquid (GSL)-dimer phase transition as well as all the degeneracies of the model system. We show that the jump inp1(J2/J1)of FES atJ2/J1≈0.241, indicates the GSL-dimer phase transition, whereas its kinks give the signature of the GS degeneracies. The scatter plot of the first two principal components of FES shows distinct band formation for different phases. The MPSCs are obtained by using an iterative variational method (IVM) which gives the approximate eigenvalues and eigenvectors.

Novel biomarkers predict ablation outcomes in long stranding persistent atrial fibrillation

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): NIHR

Background

Ablation of long-standing persistent atrial fibrillation (LSPAF) is not always successful. The arrhythmia burden was reduced by 75% by 12 months in majority (72%) of patients with LSPAF who underwent surgical or percutaneous ablation in the CASA-AF trial. We hypothesised that biomarker(s) improve prediction of clinical success and offer insights into mechanisms.

Objective

To identify biomarkers that predict success (75% arrhythmia burden reduction) after ablation for LSPAF at 12-months.

Methods

Amongst patients participating in the CASA-AF RCT (ISRCTN18250790), pre-ablation serum samples were selected for 20 patients who met criteria for ablation-success at 12 months, and 20 who did not. Olink ProteomicsTM (Sweden) provided analyses using three biomarker panels [inflammation (INFL), cardiovascular III (CVD III), and cell cytology (CELL)] each containing 92 biomarkers. Univariate and multivariable analyses were adjusted for age, sex, BMI, LA diameter and CRP. ROC analysis was undertaken to assess the diagnostic accuracy of the biomarkers. To counter the false discovery rate, Benjamini-Hochberg correction was utilised.

Results

When patients with ablation-success and -failure were compared, no differences in demographics or cardiac function were found. On univariate analysis, several biomarkers in each panel were associated with ablation-success. Multivariable analysis narrowed the range of biomarkers and identified those that were jointly predictive of outcome: INFL (MCP1 + CD8A + CD40, Figure 1), CVD III (FAS + CPB1) and CELL (GCG + ENTPD6 + IL17RB). These joint biomarkers were analysed using ROC (Figure 2), which showed that increases of biomarkers on the INFL panel (MCP1 + CD8A + CD40) were associated with a greater risk of failure and achieved the highest AUC for prediction of outcome [0.82 (0.75-0.87)].

Conclusion

The increase in the serum concentration of markers of inflammation (MCP1 + CD8A + CD40) might be used to identify patients less likely to have sustained benefit from LSPAF ablation. Further studies are required to confirm their prognostic value as pre-procedural biomarkers.

The acute haemodynamic response with endocardial biventricular pacing: comparing RV paced and LBBB patients

Funding Acknowledgements

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Boston Scientific

Background

A third of patients that receive cardiac resynchronisation (CRT) are non-responders. Predictors of positive response include broader QRS duration, non-ischaemic aetiology and sinus rhythm, but it is still unclear whether lead placement site determines a positive responder.

Purpose

We assessed the acute haemodynamic response of endocardial biventricular pacing in patients with intrinsic left bundle brunch block (LBBB) versus LBBB due to pre-existing right ventricular pacing (RVP).

Methods

Patients who fulfilled standard criteria for CRT implantation but had failed conventional (coronary sinus) left ventricular (LV) lead placement (primary or revision) or were deemed clinical ‘non-responders after > 6 months of conventional CRT were enrolled. The acute haemodynamic response during endocardial biventricular pacing was assessed with a roving LV lead at 9 different locations (basal and mid: septal, anterior, posterior and lateral walls and apex). Acute changes in beat-to-beat systolic blood pressure (SBP) in the left ventricle were recorded and analysed.

Results

We recruited 23 patients across 10 UK centres: 14 intrinsic LBBB and 9 dependent on RVP. Patient characteristics were comparable: age (mean 67 + 10.6 years vs. 62 + 15.4 years), ischaemic (63% vs 50%), QRS (160 + 18ms vs. 190 + 36ms, p =0.07). Of the RVP group 5/9 had septal RV leads (the remainder apically positioned).

There was no difference in the SBP improvement between the groups: change in SBP ranged from -5.25 – 19.91mmHg (median 3mmHg) in RVP patients vs -5.92 – 23.03mmHg (median 3mmHg) for intrinsic LBBB. However, the improvement in SBP was more consistent across the different segments in the patients with RVP (group A), as compared to intrinsic LBBB (group B), where the lateral wall and then non-septal walls provided the greatest haemodynamic improvement.

Figure 1: depicts SBP improvement (in mmHg) during endocardial biventricular pacing in different positions within the LV for patients with RVP (A) vs underlying intrinsic LBBB (B): 9 segment model of the LV: Ant (anterior wall), Lat (lateral wall), Post (posterior wall), Sept (septum). Outer ring represents the four basal LV locations, middle ring the mid LV locations and centre ring the apex. Scale depicts mmHg improvement in SBP.

Conclusion

When implanting an LV lead for patients who are RV pacing dependent any position within the LV provides an acute haemodynamic improvement, compared with those with intrinsic LBBB, where a targeted lateral wall approach is more important. This finding corroborates the key differences in LV activation patterns for induced versus intrinsic LBBB.

Atrial fibrillation substrate mapping with decrement evoked potential mapping

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): Sociedad Española de Cardiologia.

OnBehalf

DEFINE-AF

Background

Identifying and targeting atrial substrate zones that are vulnerable to unidirectional block and slow conduction may be critical to improve the outcomes of atrial fibrillation (AF) ablation. Functional mapping of the atrial substrate with Decrement Evoked Potential (DeEP) and a single extrastimulus in this population could potentially lead to novel therapeutic strategies.

Aim

1) To systematically analyze whether the DEEP are present in the atrial tissue and their locations after pulmonary vein isolation. 2) To assess their relationship with the underlying voltage.  3) To assess the presence of DEEP as a function of the subtype of AF.

Methods

Consecutive patients with AF undergoing ablation were prospectively enrolled at 3 institutions. A biatrial voltage map was created and after pulmonary vein isolation (PVI). A drive train and an extrastimulus (atrial refractory period + 20ms) was delivered from an epicardial site (proximal CS) and an endocardial site (left atrial appendage (LAA). A multipolar mapping catheter was sequentially placed at 8 left atrial sites and 5 right atrial sites. Electrograms (EGMs) that showed a local delay of >10ms in activation with the extrastimulus were identified as DEEPs. Patients were followed for a mean of 11 ± 5 months

Results

74 patients, 63 pers AF (85%), mean age 62 ± 8, mean LA size 41 ±12 mm were enrolled. Of 19240 EGMs analyzed, 8.2% showed DEEPs (54.6% with CS pacing and 45.4% with LAA pacing, p = 0.0001). The mean local decrement seen was 39 ms. Most DEEPs (76.2%) were identified in sites with a normal EGM at baseline with preserved voltages. DEEPs were differentially distributed within the regions mapped, more frequently in LA than RA (9.2% vs 6.6%, p < 0.0001). Patients with persistent AF had a higher proportion of DEEPs than patients with paroxysmal AF (9.7% vs 5.1%, p < 0.001).

Conclusions

Atrial DEEPs are: 1) More often identified when pacing endocardially. 2) More common in patients with persistent AF. 3) More frequent in the LA than in the RA. 4) Mostly located in regions with normal voltages at baseline. All those findings suggest the importance of the functional substrate mapping in the atrium and could lead to novel therapeutic targets. Abstract Figure. Example of atrial DEEP

Brown fat activity determined by infrared thermography and thermogenesis measurement using whole body calorimetry (BRIGHT Study)

To assess BAT activity in humans at a population level, infrared thermography (IRT) represents a safe, readily repeatable and affordable alternative to 18F-FDG-PET. Building upon a previously proposed method by our laboratory, we further refined the image computational algorithm to quantify BAT activation in the cervical-supraclavicular (C-SCV) region of healthy young men under thermo-neutral and cold exposure conditions. Additionally, we validated the whole-body calorimeter (WBC) in reliably measuring cold-induced thermogenesis. The temperature gradient between C-SCV-deltoid regions, and the corresponding difference in heat power output, increased upon cold air exposure relative to thermo-neutral conditions (by 74.88 %, p<0.0001; and by 71.34 %, p<0.0001 respectively). Resting and cumulative energy expenditure (EE) rose significantly (by 13.14 % and 9.12 % respectively, p=0.0001) while positive correlations between IRT measures and EE were found with cold air exposure (percentage change in heat power gradient between ROI and deltoid, cold air: r(2)=0.29, p=0.026, Pearson's correlation). IRT and WBC can be used to study BAT activation. The refined algorithm allows for more automation and objectivity in IRT data analysis, especially under cold air exposures.

P2831Safety of atrial fibrillation catheter ablation in the elderly

Background

Catheter ablation for drug refractory, symptomatic atrial fibrillation (AF), is becoming increasingly common and can be beneficial in alleviating symptoms. However, in the elderly, there are concerns about the risks an invasive procedure poses, with limited published data available in those aged over 80 years.

Purpose

To determine the complication risk of AF catheter ablation in the elderly

Methods

Complications were identified from patient records in 3156 consecutive patients who underwent radiofrequency catheter ablation for AF, at a tertiary cardiology centre between 2013–2017. All cases were performed under general anesthesia.

Results

In this cohort of 3156 patients (mean age= 62.9±11.0 years, female = 29.9%), 90 (2.85%) (mean age= 66±10.0 years, female = 49.5%) complications were identified. In patients aged ≥80 years, complications occurred in 5 out of 99 patients (5.05%) (mean age= 82.6±1.2, female=100%), compared to 85 out of 3057 patients (2.78%) in those aged <80 years (mean age= 65±10.3, female = 49.4%). The difference was not significant p=0.18. Complications in the elderly all occurred acutely, and included groin haematoma (2.02%), pneumonia (2.02%) and pericardial effusion (1.01%).

Conclusion

Catheter ablation for AF in patients ≥80 years of age, is not associated with a significant increase in complication risk, compared to those who are younger.

P978Core to block: a new ablation strategy for treating persistent atrial fibrillation

Background

Ablation strategy targeting the core of atrial fibrillation (AF) rotors alone can lead to both stabilisation and destabilisation of rotational activity. Non-contact dipole density mapping system is designed to rapidly identify dynamic regional atrial activation patterns of interest (API) during AF.

Purpose

To assess the feasibility of an ablation strategy consisted of pulmonary vein isolation + targeting the core of APIs followed by linear ablation to the nearest non-conducting boundary to treat persistent AF.

Methods

The ablation strategy includes: 1. Antral pulmonary vein electrical isolation (APVI); 2. APIs (focal, localised rotational and localised irregular activation; Figure1) detection by dipole density mapping; 3. API core ablation followed by linear ablation to the nearest non-conduction barrier (APVI/mitral valve); 4. repeat step 2 and 3 in LA (RA, if necessary) until sinus rhythm is achieved.

Results

Consecutive 40 persistent AF patients (mean 62±12 years, 29 males, AF duration 10±4 months, LA diameter 42±9 mm) were included from 2 centres. An average of 2.0±0.7 APIs per patient were targeted post-APVI. Acute AF termination by ablation was achieved in 27/40 (68%) patients. The mean ablation time of APVI and “Core to block” was 33±12 mins and 31±22 mins, respectively. No major complication occurred. During a mean follow-up of 12±5 months, 32/40 patients (80%) maintained sinus rhythm.

Conclusion

APVI + “Core to block” guided by the dipole density mapping is feasible for treating persistent AF. A larger randomised study is needed to test the effectiveness of this ablation strategy.

Acknowledgement/Funding

None

P3756Diverse activation patterns during persistent atrial fibrillation characterised by dipole density non-contact mapping

Background

Global simultaneous recording of activation during atrial fibrillation (AF) can elucidate underlying mechanisms contributing to AF maintenance. A better understanding of these mechanisms may allow for a personalised ablation strategy to treat persistent AF.

Purpose

To characterise left atrial endocardial activation patterns during AF using a novel non-contact dipole density mapping.

Methods

Activation patterns were characterised into three sub-types: (i) focal with centrifugal activation (FCA); (ii) localised rotational activation (LRA); (iii) localised irregular activation (LIA). Continuous activation patterns were quantified and distributed in the left atrium.

Results

A total of 144 persistent AF segments with 1068 activation patterns from 25 patients were analysed. The most common pattern was LIA (63%), which consist of four disparate features: slow conduction (45%), pivoting (30%), collision (16%) and acceleration (7%). LRA was the second commonest pattern (20%). FCA (17%) arose frequently from the PVs/ostia. Continuous AF activations comprise multiple combinations of FCA, LRA and LIA, transitioning from one to the next without a discernible order. Preferential conduction areas were typically seen in mid-anterior (48%) and lower-posterior (40%) walls where dominant activations were made up of LRA and LIA.

Conclusion

AF is characterised by heterogenous activation patterns that vary between individuals. Clinical implications of individualised ablation strategies guided by dipole density mapping will have to be determined.

Acknowledgement/Funding

None

Factors associated with sputum culture conversion in multidrug-resistant pulmonary tuberculosis

INTRODUCTION

Sputum culture conversion in pulmonary multidrug-resistant tuberculosis (MDR-TB) is important to make treatment-related decisions and prevent transmission of disease.

OBJECTIVE

To identify factors associated with sputum culture conversion, and to determine time to culture conversion and the impact of culture conversion on successful treatment outcomes in MDR-/rifampicin (RMP) resistant TB.

METHOD

Retrospective analysis of data from treatment cards and registers of MDR-/RMP-resistant patients initiated on treatment under India's Revised National TB Control Programme in Delhi, West Bengal and Kerala from January 2009 to December 2011. Proportions were calculated and logistic regression analysis was performed.

RESULTS

Of 836 patients, 787 were analysed, 651 (83%) of whom experienced culture conversion: respectively 57%, 73% and 79% culture converted by month 3, 4 and 6 of treatment. The median time to culture conversion was 91.3 days. Patients with body mass index (BMI) 16 kg/m2 (OR 0.403, P = 0.001) and 1618 kg/m2 (OR 0.519, P = 0.039) were less likely to have culture conversion. High rates of culture conversion were observed in patients with successful treatment outcomes compared to those without treatment success (462/469, 99% vs. 183/311, 59%; P 0.0001).

CONCLUSION

Low BMI is associated with poor sputum culture conversion in MDR-/RMP-resistant TB patients. Lack of culture conversion can impact successful treatment outcomes.

Hybrid opto-chemical doping in Ag nanoparticle-decorated monolayer graphene grown by chemical vapor deposition probed by Raman spectroscopy

The novel opto-chemical doping effect in Ag nanoparticle-decorated monolayer graphene grown by chemical vapor deposition has been investigated using Raman spectroscopy for the first time. We used both noble metal nanoparticles and optical excitation, in a hybrid opto-chemical route, to tune the doping level in graphene. Metal nanoparticle-induced chemical effects and laser power-induced substrate effects alter the doping nature of graphene from p- to n-type. Compared with earlier studies, the proposed method significantly lowers the laser intensity required for optical power-dependent doping, resulting in prevention of damage to the sample due to local heating. Some other interesting observations are the enhanced peak intensity in the Raman spectrum of graphene, enhancement of the D-band intensity and the introduction of G-band splitting. This novel, cheap and easily implemented hybrid optical-chemical doping strategy could be very useful for tuning graphene plasmons on the widely used Si/SiO₂ substrates for various photonic device applications.

Effects of dietary supplementation of cinnamaldehyde and formic acid on growth performance, intestinal microbiota and immune response in broiler chickens

An experiment was conducted to investigate the effects of replacing antibiotic growth promoter (AGP) with a combination of essential oil and organic acids (EO + OA) on growth performance, gut microbiota and immune response in broiler chickens. In Experiment 1, 320 day-old broiler chicks were randomly distributed to 32 pens with 10 birds in each pen and the pens were equally allotted to four treatment groups. In Experiment 2, 120 day-old chicks were divided into the same four treatment groups, each group containing three replicated pens with 10 birds in each pen. The groups were (1) Negative Control (NC) without AGP or other growth-promoting feed additives; (2) AGP (NC + enramycin; 125 mg/kg feed; (3) OA (NC + OA; 500 mg/kg feed); and (4) EO + OA (NC + a combination of cinnamaldehyde and calcium formate; 500 mg/kg feed). Experiment 1 lasted for 40 days, whereas Experiment 2 continued for 28 days. In Experiment 2, all birds were orally challenged with Escherichia coli (108 bacteria/bird) on Day 14. Overall intake, growth and feed conversion ratio (FCR) on Day 40 had no difference (P > 0.05) among the groups in Experiment 1. In Experiment 2, growth, feed intake and FCR were not affected by any dietary treatments until Day 14, but after being challenged with E. coli, bodyweight gain and FCR improved (P < 0.05) for AGP and EO + OA compared with NC. Mortality rate was also lower (P < 0.05) for AGP and EO + OA than NC in Experiment 2. Villi height was higher (P < 0.001) in OA and EO + OA groups compared with NC and AGP groups. Any treatment did not affect (P > 0.05) the counts of total bacteria, E. coli and Lactobacillus in the contents of ileum and caecum. However, Salmonella counts in the ileal and caecal contents decreased (P < 0.001) for AGP, OA and EO + OA compared with NC group. Clostridium counts were lower for EO + OA group than for NC and AGP groups in the ileum, and for AGP, OA and EO + OA groups than for NC in the caeca (P < 0.05). Antibody titer on Day 35 against Newcastle disease vaccine was higher in EO + OA group than in NC, AGP and OA groups (P < 0.001). In conclusion, EO + OA did not affect growth and FCR in broilers. However, AGP and EO + AO improved growth performance and FCR after being challenged with E. coli. Moreover, EO + OA was effective in reducing the Clostridium count in the small intestine and caecum and increasing the villus height and antibody titer against Newcastle disease vaccine.

Diagnostic investigation of parotid neoplasms: a 16-year experience of freehand fine needle aspiration cytology and ultrasound-guided core needle biopsy

This study aimed to examine the diagnostic yield of fine needle aspiration cytology (FNAC) and ultrasound-guided core needle biopsy (USCB) in the diagnosis of parotid neoplasia. A 16-year retrospective analysis was performed of patients entered into our pathology database with a final diagnosis of parotid neoplasia. FNAC and USCB data were compared to surgical excision where available. One hundred and twenty FNAC, 313 USCB, and 259 surgical specimens were analyzed from 397 patients. Fifty-six percent of FNAC and 4% of USCB were non-diagnostic. One hundred and thirty-two (33%) patients had a final diagnosis made by USCB and did not undergo surgery. Surgery was performed in 257 (65%) patients, 226 (88%) of whom had a preoperative biopsy. Most lesions were benign, but there were 62 parotid and 13 haematological malignancies diagnosed; false-negative results were obtained in three FNAC and two USCB samples. The sensitivity and specificity of FNAC were 70% and 89%, respectively, and for USCB were 93% and 100%, respectively. This study represents the largest series of patients with a parotid neoplasm undergoing USCB for diagnosis. USCB is highly accurate with a low non-diagnostic rate and should be considered an integral part of parotid assessment.

The dipole moment of the spin density as a local indicator for phase transitions

The intra-atomic magnetic dipole moment - frequently called 〈T_z〉 term - plays an important role in the determination of spin magnetic moments by x-ray absorption spectroscopy for systems with nonspherical spin density distributions. In this work, we present the dipole moment as a sensitive monitor to changes in the electronic structure in the vicinity of a phase transiton. In particular, we studied the dipole moment at the Fe²⁺ and Fe³⁺ sites of magnetite as an indicator for the Verwey transition by a combination of x-ray magnetic circular dichroism and density functional theory. Our experimental results prove that there exists a local change in the electronic structure at temperatures above the Verwey transition correlated to the known spin reorientation. Furthermore, it is shown that measurement of the dipole moment is a powerful tool to observe this transition in small magnetite nanoparticles for which it is usually screened by blocking effects in classical magnetometry.

The high prevalence of serine protease autotransporters of Enterobacteriaceae (SPATEs) in Escherichia coli causing neonatal septicemia

Serine protease autotransporters of Enterobacteriaceae (SPATEs) are secreted proteins demonstrating diverse virulence functions. The distribution of SPATEs is studied among diarrheagenic and extraintestinal pathogenic Escherichia coli. However, the contribution of SPATEs to the virulence of neonatal septicemic Escherichia coli (NSEC) has not yet been elucidated. This study was undertaken to evaluate the prevalence and phylogenetic distribution of different subtypes of SPATEs among NSEC. The presence of virulence factors and subtypes of SPATEs among different E. coli isolates was determined by polymerase chain reaction (PCR). E. coli phylogrouping was done by triplex PCR. Clonality of the isolates was assessed by pulsed-field gel electrophoresis (PFGE). The presence of SPATEs was significantly higher among the septicemic isolates (89 %) than the fecal (7.5 %) and environmental isolates (2.5 %). Vat (vacuolating autotransporter toxin) and Sat (secreted autotransporter toxin) were found to be the two most predominant SPATEs. The incidence of SPATEs was high in septicemic isolates of phylogroups A and B1 (87 %), lacking other virulence factors. The high prevalence of SPATEs in the non-B2 phylogroups of septicemic isolates in comparison with fecal and environmental isolates indicates an association of SPATEs with NSEC. The NSEC isolates were found to be clonally distinct, suggesting that the high prevalence of SPATEs was not due to clonal relatedness of the isolates. This study is the first to show the association of SPATEs with NSEC. The presence of SPATEs in the septicemic/NSEC isolates may be considered as the most discriminatory trait studied here.

Effects of hydrolysed Saccharomyces cerevisiae yeast and yeast cell wall components on live performance, intestinal histo-morphology and humoral immune response of broilers

1. The effects of enzymatically hydrolysed whole Saccharomyces cerevisiae yeast (HY) and the pellets of yeast cell wall (YCW) on production traits, the microbiology and histo-morphology of the small intestine, and humoral immune responses against Newcastle disease virus (NDV), of Ross 308 broilers were investigated. 2. The control group received a maize-soyabean meal based basal diet for 42 days. In the treated groups the basal diet was supplemented with 1 g/kg of HY and YCW. There were 8 replicate pens per group (n = 12 birds/pen). 3. HY and YCW supplementation improved live weight (P = 0·006) and FCR (P = 0·003) at 42-d as compared with the control group. 4. In the small intestine, Salmonella spp and Escherichia coli numbers were higher (P = 0·01) in the mucosa and lower (P = 0·01) in the digesta of the HY and the YCW fed groups at 25 d of age. Lactobacillus in the duodenal and jejunal digesta was higher (P < 0·05) in the HY and the YCW fed groups as compared with the control. 5. Following oral challenge with Salmonella pullorum, Escherichia coli and Lactobacillus increased (P < 0·05) in the mucosa and decreased in the digesta (P < 0·05) of the HY and YCW supplemented groups, relative to the control. 6. Supplementation of HY and YCW increased villus height in the jejunum (P = 0·02), width of villus in the ileum (P = 0·034) and number of goblet cells in villi of the jejunum (P = 0·006) and ileum (P = 0·01). 7. YCW increased antibody level against NDV at 21 and 42 d of age compared with the control and the HY supplemented diets (P < 0·05). 8. It was concluded that HY and YCW improved growth and feed efficiency in broilers, and considering the improvements in production traits and humoral immune responses, yeast cell wall may be a better dietary tool than the hydrolysed whole yeast cell as a performance enhancer for broilers.

Identification of Vibrio harveyi as a causative bacterium for a tail rot disease of sea bream Sparus aurata from research hatchery in Malta

A bacterial disease was reported from gilthead sea bream (Sparus aurata) within a hatchery environment in Malta. Symptoms included complete erosion of tail, infection in the eye, mucous secretion and frequent mortality. A total of 540 strains were initially isolated in marine agar from different infected body parts and culture water sources. Subsequently 100 isolates were randomly selected, identified biochemically and all were found to be Vibrio harveyi-related organisms; finally from 100 isolates a total of 13 numbers were randomly selected and accurately identified as V. harveyi by 16S rRNA gene sequencing and species-specific PCR. Ribotyping of these strains with HindIII revealed total of six clusters. In vivo challenge study with representative isolates from each cluster proved two clusters each were highly pathogenic, moderately pathogenic and non-pathogenic. All 13 isolates were positive for hemolysin gene, a potential virulence factor. Further analysis revealed probably a single copy of this gene was encoded in all isolates, although not in the same locus in the genome. Although V. harveyi was reported to be an important pathogen for many aquatic organisms, to our knowledge this might be the first report of disease caused by V. harveyi and their systematic study in the sea bream hatchery from Malta.

Production and carcase traits in broiler chickens given diets supplemented with inorganic trivalent chromium and an organic acid blend

1. The study was conducted to ascertain the effects of supplemental organic acids and chromium (Cr) on production and carcase traits of broiler chickens. 2. A total of 120 1-d-old broiler chicks were divided into 4 treatment groups in a 2 x 2 factorial design (each treatment group contained 6 replicates with 5 birds per replicate). 3. The diets were supplemented with an organic acid blend containing ortho-phosphoric, formic and propionic acid and calcium propionate (1 g/kg diet) and inorganic trivalent chromium (Cr(3+)) as chromic chloride hexahydrate (0.5 mg/kg diet) either independently or together as a combination for 35 d. 4. Individual supplementation of organic acids and Cr(3+) and their combination significantly improved the food conversion ratio, hot and dressed carcase weight and weight of the wholesale cuts compared to the control group of birds. 5. Organic acids, either independently or along with Cr(3+), increased total accretion of ash in carcase. Protein accretion was improved by dietary Cr(3+) and organic acid supplementation compared to the control group and a further improvement in this regard was observed when Cr(3+) and organic acid were supplemented together. Across the treatment groups meat fat content and fat accretion were lower in birds receiving dietary Cr(3+) supplementation. 6. Circulatory Cr(3+) and meat Cr(3+) concentration increased compared to the other treatment groups when Cr(3+) was supplemented to the birds. 7. It was concluded that, instead of individual supplementation, a combination of Cr(3+) and organic acids may improve the production and carcase traits of broilers more effectively presumably because of an additive effect.

Influence of habitual diet on antioxidant status: a study in a population of vegetarians and omnivores

BACKGROUND

Antioxidant status can be used as a biomarker to assess chronic disease risk and diet can modulate antioxidant defence.

OBJECTIVE

To examine effects of vegetarian diet and variations in the habitual intakes of foods and nutrients on blood antioxidants.

SUBJECTS AND SETTING

Thirty-one vegetarians (including six vegans) and 58 omnivores, non-smokers, in Northern Ireland.

DESIGN

A diet history method was used to assess habitual diet. Antioxidant vitamins, carotenoids, uric acid, zinc- and ferric-reducing ability of plasma (FRAP) were measured in fasting plasma and activities of glutathione peroxidase (GPX), superoxide dismutase (SOD) and glutathione S-transferase (GST) and level of reduced glutathione (GSH) were measured in erythrocytes.

RESULTS

Vegetarians had approximately 15% higher levels of plasma carotenoids compared with omnivores, including lutein (P< or =0.05), alpha-cryptoxanthin P< or =0.05), lycopene (NS), alpha-carotene (NS) and beta-carotene (NS). The levels/activities of all other antioxidants measured were similar between vegetarians and omnivores. Total intake of fruits, vegetables and fruit juices was positively associated with plasma levels of several carotenoids and vitamin C. Intake of vegetables was positively associated with plasma lutein, alpha-cryptoxanthin, alpha-carotene and beta-carotene, whereas intake of fruits was positively associated with plasma beta-cryptoxanthin. Intake of tea and wine was positively associated with FRAP value, whereas intake of herbal tea associated positively with plasma vitamin C. Intakes of meat and fish were positively associated with plasma uric acid and FRAP value.

CONCLUSIONS

The overall antioxidant status was similar between vegetarians and omnivores. Good correlations were found between intakes of carotenoids and their respective status in blood.

Juvenile idiopathic arthritis

This study attempts to determine the clinical manifestations, severity and immunological features of JIA and its influence on growth and associated cardiac involvement in children below 16 years of age. This is a cross sectional study in a tertiary referral center on 50 consecutive children below the age of 16 years. Each patient was thoroughly examined and scored on Juvenile Arthritis Functional Assessment Scale. Relevant blood tests, cardiac and ophthalmic evaluation was done. Growth patterns were noted. There was an overall equal sex ratio, though there was a male preponderance in the systemic and oligoarthritis groups. Disturbance of growth frequently occurred in children suffering from JIA. Cardiac involvement should be looked for in cases of JIA. Significant number of cases of PSRA is diagnosed in children presenting with chronic arthritis.

Primary neurological manifestations of lung cancer--a retrospective analysis of 8 patients

Neurological manifestations are reported in 5 to 10% of cases of lung cancer. We present a series of 216 consecutive patients of lung cancer of which 8 patients presented first with neurological manifestations without overt respiratory symptoms. The present study aimed to identify the number of patients of lung cancer presenting with primary neurological symptoms, the nature of the presentations, and the outcome of these patients among 216 patients who presented over a 2 year period in the Institute of Postgraduate Medical Education and Research, Kolkata. Out of 8 patients, 3 patients presented with seizures, 3 patients with hemiparesis and 2 patients with paraparesis. Thus, 3.7% (8/216) of patients in our series presented with a neurological manifestation. We concluded that primary neurological manifestations are rare in lung cancer. The lungs should be the first site of evaluation in a case of a cerebral metastasis with an unknown primary.

A study of relapse after MDT in a district in West Bengal, India

A study was undertaken to estimate the magnitude of the problem of relapse and to identify factors responsible for relapse in leprosy units that were delivering MDT in Purulia District of West Bengal. From records patients were classified as "Relapse" or "Not relapse". "Not relapse" patients were selected by simple random sampling from the Surveillance Register and were matched according to age, sex, and the leprosy control unit. 128 cases ("Relapse") and 128 controls ("Not relapse") were interviewed in the clinic using a pre-tested questionnaire. Details of methods to identify and confirm relapse were circulated to all reporting units for ensuring uniformity and reliability. NGOs covered 42% of the population, while the State Government covered the remaining. The patients had been followed up after completion of treatment for a period of two years in PB leprosy and for five years in MB leprosy. The study revealed that the relapse rate was 1.71/1000 person-years for original PB cases and 0.76/1000 person-years for original MB cases. The study also showed that history of contact with an active leprosy patient and irregular treatment led more PB cases to relapse than control cases. All patients with an initial BI of 3+ relapsed with a BI of 1+ or 2+.