Estimation of country-specific tuberculosis resistance antibiograms using pathogen genomics and machine learning

BACKGROUND

Global tuberculosis (TB) drug resistance (DR) surveillance focuses on rifampicin. We examined the potential of public and surveillance Mycobacterium tuberculosis (Mtb) whole-genome sequencing (WGS) data, to generate expanded country-level resistance prevalence estimates (antibiograms) using in silico resistance prediction.

METHODS

We curated and quality-controlled Mtb WGS data. We used a validated random forest model to predict phenotypic resistance to 12 drugs and bias-corrected for model performance, outbreak sampling and rifampicin resistance oversampling. Validation leveraged a national DR survey conducted in South Africa.

RESULTS

Mtb isolates from 29 countries (n=19 149) met sequence quality criteria. Global marginal genotypic resistance among mono-resistant TB estimates overlapped with the South African DR survey, except for isoniazid, ethionamide and second-line injectables, which were underestimated (n=3134). Among multidrug resistant (MDR) TB (n=268), estimates overlapped for the fluoroquinolones but overestimated other drugs. Globally pooled mono-resistance to isoniazid was 10.9% (95% CI: 10.2-11.7%, n=14 012). Mono-levofloxacin resistance rates were highest in South Asia (Pakistan 3.4% (0.1-11%), n=111 and India 2.8% (0.08-9.4%), n=114). Given the recent interest in drugs enhancing ethionamide activity and their expected activity against isolates with resistance discordance between isoniazid and ethionamide, we measured this rate and found it to be high at 74.4% (IQR: 64.5-79.7%) of isoniazid-resistant isolates predicted to be ethionamide susceptible. The global susceptibility rate to pyrazinamide and levofloxacin among MDR was 15.1% (95% CI: 10.2-19.9%, n=3964).

CONCLUSIONS

This is the first attempt at global Mtb antibiogram estimation. DR prevalence in Mtb can be reliably estimated using public WGS and phenotypic resistance prediction for key antibiotics, but public WGS data demonstrates oversampling of isolates with higher resistance levels than MDR. Nevertheless, our results raise concerns about the empiric use of short-course fluoroquinolone regimens for drug-susceptible TB in South Asia and indicate underutilisation of ethionamide in MDR treatment.

Interim safety and immunogenicity of COVID-19 omicron BA.1 variant-containing vaccine in children in the USA: an open-label non-randomised phase 3 trial

BACKGROUND

Variant-containing mRNA vaccines for COVID-19 to broaden protection against SARS-CoV-2 variants are recommended based on findings in adults. We report interim safety and immunogenicity of an omicron BA.1 variant-containing (mRNA-1273.214) primary vaccination series and booster dose in paediatric populations.

METHODS

This open-label, two-part, non-randomised phase 3 trial enrolled participants aged 6 months to 5 years at 24 US study sites. Eligible participants were generally healthy or had stable chronic conditions, without known SARS-CoV-2 infection in the previous 90 days. Individuals who were acutely ill or febrile 1 day before or at the screening visit or those who previously received other COVID-19 vaccines (except mRNA-1273 for part 2) were excluded. In part 1, SARS-CoV-2-vaccine-naive participants received two-dose mRNA-1273.214 (25 μg; omicron BA.1 and ancestral Wuhan-Hu-1 mRNA) primary series. In part 2, participants who previously completed the two-dose mRNA-1273 (25 μg) primary series in KidCOVE (NCT04796896) received a mRNA-1273.214 (10 μg) booster dose. Primary study outcomes were safety and reactogenicity of the mRNA-1273.214 primary series (part 1) or booster dose (part 2) as well as the inferred effectiveness of mRNA-1273.214 based on immune responses against ancestral SARS-CoV-2 (D614G) and omicron BA.1 variant at 28 days post-primary series (part 1) or post-booster dose (part 2). The safety set included participants who received at least one dose of the study vaccine; the immunogenicity set included those who provided immunogenicity samples. Interim safety and immunogenicity are summarised in this analysis as of the data cutoff date (Dec 5, 2022). This trial is registered with ClinicalTrials.gov, NCT05436834.

FINDINGS

Between June 21, 2022, and Dec 5, 2022, 179 participants received one or more doses of mRNA-1273.214 primary series (part 1) and 539 received a mRNA-1273.214 booster dose (part 2). The safety profile within 28 days after either dose of the mRNA-1273.214 primary series and the booster dose was consistent with that of the mRNA-1273 primary series in this age group, with no new safety concerns or vaccine-related serious adverse events observed. At 28 days after primary series dose 2 and the booster dose, both mRNA-1273.214 primary series (day 57, including all participants with or without evidence of prior SARS-CoV-2 infection at baseline) and booster (day 29, including participants without evidence of prior SARS-CoV-2 infection at baseline) elicited responses that were superior against omicron-BA.1 (geometric mean ratio part 1: 25·4 [95% CI 20·1-32·1] and part 2: 12·5 [11·0-14·3]) and non-inferior against D614G (part 1: 0·8 [0·7-1·0] and part 2: 3·1 [2·8-3·5]), compared with neutralising antibody responses induced by the mRNA-1273 primary series (in a historical comparator group).

INTERPRETATION

mRNA-1273.214 was immunogenic against BA.1 and D614G in children aged 6 months to 5 years, with a comparable safety profile to mRNA-1273, when given as a two-dose primary series or a booster dose. These results are aligned with the US Centers for Disease Control and Prevention recommendations for the use of variant-containing vaccines for continued protection against the emerging variants of SARS-CoV-2.

FUNDING

Moderna.

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.

Associations of Immunogenicity and Reactogenicity After Severe Acute Respiratory Syndrome Coronavirus 2 mRNA-1273 Vaccine in the COVE and TeenCOVE Trials

BACKGROUND

The reactogenicity and immunogenicity of coronavirus disease 2019 (COVID-19) vaccines are well studied. Little is known regarding the relationship between immunogenicity and reactogenicity of COVID-19 vaccines.

METHODS

This study assessed the association between immunogenicity and reactogenicity after 2 mRNA-1273 (100 µg) injections in 1671 total adolescent and adult participants (≥12 years) from the primary immunogenicity sets of the blinded periods of the Coronavirus Efficacy (COVE) and TeenCOVE trials. Associations between immunogenicity through day 57 and solicited adverse reactions (ARs) after the first and second injections of mRNA-1273 were evaluated among participants with and without solicited ARs using linear mixed-effects models.

RESULTS

mRNA-1273 reactogenicity in this combined analysis set was similar to that reported for these trials. The vaccine elicited high neutralizing antibody (nAb) geometric mean titers (GMTs) in evaluable participants. GMTs at day 57 were significantly higher in participants who experienced solicited systemic ARs after the second injection (1227.2 [1164.4-1293.5]) than those who did not (980.1 [886.8-1083.2], P = .001) and were associated with fever, chills, headache, fatigue, myalgia, and arthralgia. Significant associations with local ARs were not found.

CONCLUSIONS

These data show an association of systemic ARs with increased nAb titers following a second mRNA-1273 injection. While these data indicate systemic ARs are associated with increased antibody titers, high nAb titers were observed in participants after both injections, consistent with the immunogenicity and efficacy in these trials. These results add to the body of evidence regarding the relationship of immunogenicity and reactogenicity and can contribute toward the design of future mRNA vaccines.

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

Management of childhood MDR-TB in Europe and Central Asia: report of a Regional WHO meeting

BACKGROUND: As the WHO European Region has the highest proportion of multidrug-resistant TB (MDR-TB) among total incident TB cases, many children and adolescents are at risk of MDR-TB infection and disease.METHODS: We performed an electronic survey of clinicians and TB programme personnel who attended the 2020 Regional Consultation on child and adolescent TB organised by the WHO Regional Office. We characterised access to diagnostics and drugs, and practices in the prevention and management of child and adolescent MDR-TB.RESULTS: Children and adolescents are inconsistently represented in national guidelines and budgets; child-friendly drug formulations for MDR-TB treatment are insufficiently available in 57% of countries, and 32% of countries reported paediatric drug stock-outs. The novel drugs, bedaquiline and delamanid, are accessible by respectively 80% and 60% of respondent countries. Respondents were asked how many children were diagnosed with MDR-TB in 2019, and a comparison of this number to modelled estimates of incidence (to identify the case detection gap) and WHO notifications (to identify the case reporting gap) showed substantial differences in both comparisons.CONCLUSIONS: Better representation of this patient group in guidelines and budgets, greater access to drugs and improved reporting are essential to reach TB elimination in this Region.

1397. Modern Lineages of Mycobacterium tuberculosis Were Recently Introduced in Western India and Demonstrate Increased Transmissibility

Background

Mycobacterium tuberculosis (Mtb) transmissibility may vary between lineages (or variants) and this may contribute to the slow decline of tuberculosis incidence. The objective of our study was to compare transmissibility across four major lineages (L1-4) of Mtb in Pune, India.

Methods

We performed whole-genome sequencing (WGS) of Mtb isolated from sputum culture of adult patients with pulmonary TB. We performed genotypic susceptibility testing for both first- and second-line drugs using a previously validated random forest predictor. We identified single nucleotide polymorphisms and generated a multiple sequence alignment excluding drug resistance conferring mutations to avoid skewing the phylogeny due to convergent evolution in these regions. We used Bayesian molecular dating to generate phylogenies and compared tree characteristics using a two-sample Kolmogorov-Smirnov (KS) test.

Results

Of the 642 isolates from distinct study participants that underwent WGS, 612 met quality criteria. The median age of participants was 31 years (range 18-74), the majority were male (64.7%) and sputum smear-positive (83.3%), and 6.7% had co-infection with HIV (Table 1). There was no significant difference in baseline characteristics between lineages. The majority of isolates belonged to L3 (44.6%). The majority (61.1%) of multidrug-resistant (MDR, resistant to isoniazid and rifampin) isolates belonged to L2. In phylogenetic analysis, we found evidence of higher transmissibility of L2 as indicated by shorter branch lengths (i.e., less time had elapsed between transmission and sampling) and more genetic similarity (smaller pairwise single nucleotide polymorphism [SNP] distances) among L2 isolates as compared to other lineages (Figure 1). Branching times for L2 and L4 were smaller than L1 and L3 indicating recent introduction into the region (p < 0.001 [KS test]).

Figure 1: Lineage-wise distribution of A) phylogenetic tree branch lengths (log) and B) pairwise single nucleotide polymorphism (SNP) distance, using 612 tuberculosis isolates from Pune, India. P values calculated using two-sample Kolmogorov-Smirnov test.

Table 1: Demographic characteristics of study participants included in the study, by lineage.

Conclusion

Modern Mtb lineages (L2 and L4) were relatively recently introduced in western India, as compared to older lineages (L1 and L3), with the more drug-resistant L2 showing higher transmissibility. These findings highlight the need for early detection and treatment initiation to interrupt transmission with important implications for antimicrobial stewardship and heightened surveillance of TB resistance rates.

Disclosures

All Authors: No reported disclosures

Too tired to stay

[Figure: see text].

Tuberculosis Pathways to Care and Transmission of Multidrug-Resistance in India

Rationale

India is experiencing a regional increase in cases of multidrug-resistant tuberculosis (MDR-TB).

Objectives

Given the complexity of MDR-TB diagnosis and care, we sought to address key knowledge gaps in MDR risk factors, care delays, and drivers of delay to help guide disease control.

Methods

From January 2018 to September 2019, we conducted interviews with adults registered with the National TB Elimination Program for MDR (n = 128) and non–MDR-TB (n = 269) treatment to quantitatively and qualitatively study care pathways. We collected treatment records and GeneXpert-TB/RIF diagnostic reports.

Measurements and Main Results

MDR-TB was associated with young age and crowded residence. GeneXpert rifampicin resistance diversity was measured at 72.5% Probe E. Median time from symptom onset to diagnosis of MDR was 90 days versus 60 days for non-MDR, Wilcoxon P < 0.01. Delay decreased by a median of 30 days among non-MDR patients with wider access to GeneXpert, Wilcoxon P = 0.02. Pathways to care were complex, with a median (interquartile range) of 4 (3–5) and 3 (2–4) encounters for MDR and non-MDR, respectively. Of patients with MDR-TB, 68% had their first encounter in the private sector, and this was associated with a larger number of subsequent healthcare encounters and catastrophic expenditure.

Conclusions

The association of MDR with young age, crowding, and low genotypic diversity raises concerns of ongoing MDR transmission fueled by long delays in care. Delays are decreasing with GeneXpert use, suggesting the need for routine use in presumptive TB. Qualitatively, we identify the need to improve patient retention in the National TB Elimination Program and highlight patients’ trust relationship with private providers.

GenTB: A user-friendly genome-based predictor for tuberculosis resistance powered by machine learning

BACKGROUND

Multidrug-resistant Mycobacterium tuberculosis (Mtb) is a significant global public health threat. Genotypic resistance prediction from Mtb DNA sequences offers an alternative to laboratory-based drug-susceptibility testing. User-friendly and accurate resistance prediction tools are needed to enable public health and clinical practitioners to rapidly diagnose resistance and inform treatment regimens.

RESULTS

We present Translational Genomics platform for Tuberculosis (GenTB), a free and open web-based application to predict antibiotic resistance from next-generation sequence data. The user can choose between two potential predictors, a Random Forest (RF) classifier and a Wide and Deep Neural Network (WDNN) to predict phenotypic resistance to 13 and 10 anti-tuberculosis drugs, respectively. We benchmark GenTB's predictive performance along with leading TB resistance prediction tools (Mykrobe and TB-Profiler) using a ground truth dataset of 20,408 isolates with laboratory-based drug susceptibility data. All four tools reliably predicted resistance to first-line tuberculosis drugs but had varying performance for second-line drugs. The mean sensitivities for GenTB-RF and GenTB-WDNN across the nine shared drugs were 77.6% (95% CI 76.6-78.5%) and 75.4% (95% CI 74.5-76.4%), respectively, and marginally higher than the sensitivities of TB-Profiler at 74.4% (95% CI 73.4-75.3%) and Mykrobe at 71.9% (95% CI 70.9-72.9%). The higher sensitivities were at an expense of ≤ 1.5% lower specificity: Mykrobe 97.6% (95% CI 97.5-97.7%), TB-Profiler 96.9% (95% CI 96.7 to 97.0%), GenTB-WDNN 96.2% (95% CI 96.0 to 96.4%), and GenTB-RF 96.1% (95% CI 96.0 to 96.3%). Averaged across the four tools, genotypic resistance sensitivity was 11% and 9% lower for isoniazid and rifampicin respectively, on isolates sequenced at low depth (< 10× across 95% of the genome) emphasizing the need to quality control input sequence data before prediction. We discuss differences between tools in reporting results to the user including variants underlying the resistance calls and any novel or indeterminate variants CONCLUSIONS: GenTB is an easy-to-use online tool to rapidly and accurately predict resistance to anti-tuberculosis drugs. GenTB can be accessed online at https://gentb.hms.harvard.edu , and the source code is available at https://github.com/farhat-lab/gentb-site .

Globally diverse Mycobacterium tuberculosis resistance acquisition: a retrospective geographical and temporal analysis of whole genome sequences

Background

Mycobacterium tuberculosis whole genome sequencing (WGS) data can provide insights into temporal and geographical trends in resistance acquisition and inform public health interventions. We aimed to use a large clinical collection of M tuberculosis WGS and resistance phenotype data to study how, when, and where resistance was acquired on a global scale.

Methods

We did a retrospective analysis of WGS data. We curated a set of clinical M tuberculosis isolates with high-quality sequencing and culture-based drug susceptibility data (spanning four lineages and 52 countries in Africa, Asia, the Americas, and Europe) using public databases and literature curation. For inclusion, sequence quality criteria and country of origin data were required. We constructed geographical and lineage specific M tuberculosis phylogenies and used Bayesian molecular dating with BEAST, version 1.10.4, to infer the most recent common susceptible ancestor age for 4869 instances of resistance to ten drugs.

Findings

Between Jan 1, 1987, and Sept 12, 2014, of 10 299 M tuberculosis clinical isolates, 8550 were curated, of which 6099 (71%) from 15 countries met criteria for molecular dating. The number of independent resistance acquisition events was lower than the number of resistant isolates across all countries, suggesting ongoing transmission of drug resistance. Ancestral age distributions supported the presence of old resistance, 20 years or more before, in most countries. A consistent order of resistance acquisition was observed globally starting with resistance to isoniazid, but resistance ancestral age varied by country. We found a direct correlation between gross domestic product per capita and resistance age (r ²=0·47; p=0·014). Amplification of fluoroquinolone and second-line injectable resistance among multidrug-resistant isolates is estimated to have occurred very recently (median ancestral age 4·7 years [IQR 1·9-9·8] before sample collection). We found the sensitivity of commercial molecular diagnostics for second-line resistance to vary significantly by country (p<0·0003).

Interpretation

Our results highlight that both resistance transmission and amplification are contributing to disease burden globally but vary by country. The observation that wealthier nations are more likely to have old resistance (most recent common susceptible ancestor >20 years before isolation) suggests that programmatic improvements can reduce resistance amplification, but that fit resistant strains can circulate for decades subsequently implies the need for continued surveillance.

Tuberculosis in Pediatric Solid Organ and Hematopoietic Stem Cell Recipients

Children undergoing solid organ and hematopoietic stem cell transplantation are at high risk of morbidity and mortality from tuberculosis (TB) disease in the post-transplant period. Treatment of TB infection and disease in the post-transplant setting is complicated by immunosuppression and drug interactions. There are limited data that address the unique challenges for the management of TB in the pediatric transplant population. This review presents the current understanding of the epidemiology, clinical presentation, diagnosis, management, and prevention for pediatric transplant recipients with TB infection and disease. Further studies are needed to improve diagnosis of TB and optimize treatment outcomes for these patients.

349. Hardware-Associated Multidrug-resistant Pseudomonas aeruginosa Meningitis Treated with Ceftolozane-Tazobactam

Background

Although new treatment options for resistant gram negative rods have been recently developed, data on the use of these novel antibiotics for the treatment of central nervous system (CNS) infections is limited.

Methods

We present the case of a 9-year-old with a complex medical history including cerebral palsy and ventriculoperitoneal shunt dependence who was found to have highly resistant Pseudomonas aeruginosa growing from multiple cerebrospinal fluid (CSF) cultures. Susceptibility testing revealed resistance to multiple classes of antibiotics including carbapenems. Multiple antibiotics were considered for treatment; factors including molecular size, lipophilicity, plasma protein binding, and active transport as well as previously published data were weighed in selecting an antibiotic.

Results

The patient was treated with 28 days of ceftolozane-tazobactam. CSF cultures cleared following externalization of the ventriculoperitoneal shunt to an external ventricular drain. There was no recrudescence of Pseudomonas aeruginosa in the CSF following clearance.

Conclusion

We present the first reported case of ceftolozane-tazobactam used as the sole agent for treatment of resistant gram negative rod infection in the CNS. This agent may be a reasonable choice for other patients requiring treatment of highly resistant infections in this protected space.

Disclosures

Ofer Levy, MD, PhD, Avidea (Other Financial or Material Support, collaboration)Exicure (Other Financial or Material Support, collaboration)Multiple patents (Other Financial or Material Support, I am a named inventor on patents related to vaccine adjuvants)

1653. Estimation of country-specific tuberculosis antibiograms using a wide and deep neural net on a large genomic dataset

Background

Improved estimates of drug resistant tuberculosis (TB) burden are needed to aid control efforts. The World Health Organization (WHO) currently reports estimates for rifampin resistance (RR) or multidrug resistance (MDR) at the national level. Resistance rates to other first-line and second-line agents, e.g. ethambutol, pyrazinamide, and aminoglycosides, are rarely available, even at the country level. Our objective was to generate country and drug specific resistance prevalence estimates (antibiograms) using in silico phenotype prediction and curated public and surveillance Mycobacterium tuberculosis (MTB) genomic data.

Methods

We curated MTB genomes either by sequencing or from published literature and excluded genomes that did not meet our quality criteria (i.e. at least 10X depth in >95% of the genome). A machine learning model previously trained to predict phenotypic resistance in MTB with high accuracy, a wide and deep neural net (WDNN), was used to predict resistance to ten drugs. We corrected for resistance oversampling in genomic data by conditioning on RR and using country specific surveillance MDR/RR rates reported by the WHO.

Results

Of the 49,851 MTB genomes curated, 33,873 isolates met quality criteria. Of these, geographic data was available for 22,838 genomes. Antibiograms were generated for nine first- and second-line drugs for 36 countries. Among countries with at least 100 isolates, a high rate of resistance to fluoroquinolones and second line injectables was seen among isolates from the Republic of Moldova (15.4% [CI = 13.7-16.7%] moxifloxacin resistant, 6.3% [CI = 5.5-6.8%] kanamycin resistant, n = 330) and Russian Federation (9.3% [CI = 9.1-9.4] moxifloxacin resistant, 5.4% [CI = 5.3-5.5%] kanamycin resistant, n = 1011) (Figure 1).

Figure 1: Antibiograms created using genotypic data for isolates from Republic of Moldova (n=330, rifampin-resistance rate correction: 29%, range 26-31% among new tuberculosis cases);and Russian Federation (n=1011, rifampin-resistance rate correction 35%, range 34-35%, among new tuberculosis cases. rif: rifampin, inh: isoniazid, pza: pyrazinamide, emb: ethambutol, str: streptomycin, cap: capreomycin, amk: amikacin, kan: kanamycin, moxi: moxifloxacin

Conclusion

The estimation of antibiotic resistance prevalence in MTB for pyrazinamide, ethambutol and second-line agents can be aided by the use of in silico models of drug resistance. A high rate of resistance to second-line drugs precludes large scale roll out of short-course WHO regimens for treatment of MDR-TB for empiric use in certain countries. The use of whole genome sequencing for resistance surveillance can inform policy on optimal national regimen choice for TB treatment.

Disclosures

All Authors: No reported disclosures

Severe Acute Respiratory Syndrome Coronavirus 2 Infection in Febrile Neonates

Most severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections in pediatric patients are mild or asymptomatic. However, infants have emerged at higher risk of hospitalization and severe outcomes in pediatric coronavirus disease 2019 (COVID-19). We report a case series of 4 full-term neonates hospitalized with fever and found to have SARS-CoV-2 infection with a spectrum of illness severities. Two neonates required admission to the intensive care unit for respiratory insufficiency and end organ involvement. Half of the patients were found to have a coinfection. One neonate received antiviral therapy with remdesivir and is, to our knowledge, the youngest patient to receive this drug for COVID-19. All neonates had favorable outcomes.

Enhanced expression of recombinant proteins in Escherichia coli by co-expression with Vibrio parahaemolyticus CsgG, a pore-forming protein of the curli biogenesis pathway

AIM

To test whether engineered nanopores on the outer membrane (OM) of Escherichia coli can increase expression of heterologous proteins by making additional nutrients available to the host.

METHODS AND RESULTS

Outer membrane nanopores were generated by expressing recombinant Vibrio parahaemolyticus CsgG (rVpCsgG), which spontaneously assembles into a pore-forming channel on the OM, allowing spontaneous diffusion of small chemical entities from the exterior. Protein expression was probed using a reporter protein, sfGFP, expressed on a second compatible plasmid. OM pore formation was shown by acquired erythromycin sensitivity in cells transformed with rVpCsgG, influx of propidium iodide as well as by surface localization of recombinant CsgG by immunogold-labeled transmission electron microscopy. Expression of recombinant CsgG showed increased growth and also enhanced expression of sfGFP in minimal medium and is due to both enhanced transcription as well as translation. Similar enhancement of expression was also observed for a number of different proteins of different origin, sizes and nature.

CONCLUSIONS

Our findings clearly demonstrate that engineered nanopores on the OM of E. coli enhance expression of different heterologous proteins in minimal medium.

SIGNIFICANCE AND IMPACT OF THE STUDY

Vibrio parahaemolyticus CsgG β-nanopore mediated co-expression strategy to improve recombinant protein expression is fully compatible with other methods of protein expression enhancement, and therefore can be a useful tool in biotechnology particularly for whole-cell bio-transformations for production of secondary metabolite.

Complete Heart Block, Severe Ventricular Dysfunction, and Myocardial Inflammation in a Child With COVID-19 Infection

A young child presented with severe ventricular dysfunction and troponin leak in the setting of coronavirus disease-2019. He developed intermittent, self-resolving, and hemodynamically insignificant episodes of complete heart block that were diagnosed on telemetry and managed conservatively. This report is the first description of coronavirus disease-2019-induced transient complete heart block in a child. (Level of Difficulty: Intermediate.).

WITHDRAWN: Complete Heart Block, Severe Ventricular Dysfunction and Myocardial Inflammation in a Child with COVID-19 Infection

The Publisher regrets that this article is an accidental duplication of an article that has already been published, https://doi.org/10.1016/j.jaccas.2020.05.023>. The duplicate article has therefore been withdrawn. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.

Adolescent Burmese Refugees Perspectives on Determinants of Health

Over 70,000 Burmese refugees have resettled in the United States in the past decade. While Burmese adolescents quickly acculturate into American society, their perspectives on health are not well-known. The purpose of this study was to identify adolescent Burmese refugee perspectives on determinants of health and health-related experiences after resettlement. In this qualitative study, Burmese adolescents took photographs depicting health-related experiences that were used as elicitation tools during focus groups. These discussions were recorded, transcribed, and analyzed for themes. Participants described positive determinants of health, including family and church. Rampant tobacco use was identified by the participants as a determinant of poor health within the Burmese community. Notably, the participants were proud to serve as liaisons within their community, despite the stressful nature of this role. Our results highlight the need to screen this population for anxiety, secondary to serving as a liaison for their community, as well as tobacco use.

Whole genome sequencing identifies bacterial factors affecting transmission of multidrug-resistant tuberculosis in a high-prevalence setting

Whole genome sequencing (WGS) can elucidate Mycobacterium tuberculosis (Mtb) transmission patterns but more data is needed to guide its use in high-burden settings. In a household-based TB transmissibility study in Peru, we identified a large MIRU-VNTR Mtb cluster (148 isolates) with a range of resistance phenotypes, and studied host and bacterial factors contributing to its spread. WGS was performed on 61 of the 148 isolates. We compared transmission link inference using epidemiological or genomic data and estimated the dates of emergence of the cluster and antimicrobial drug resistance (DR) acquisition events by generating a time-calibrated phylogeny. Using a set of 12,032 public Mtb genomes, we determined bacterial factors characterizing this cluster and under positive selection in other Mtb lineages. Four of the 61 isolates were distantly related and the remaining 57 isolates diverged ca. 1968 (95%HPD: 1945-1985). Isoniazid resistance arose once and rifampin resistance emerged subsequently at least three times. Emergence of other DR types occurred as recently as within the last year of sampling. We identified five cluster-defining SNPs potentially contributing to transmissibility. In conclusion, clusters (as defined by MIRU-VNTR typing) may be circulating for decades in a high-burden setting. WGS allows for an enhanced understanding of transmission, drug resistance, and bacterial fitness factors.

Safety and Tolerability of Moxifloxacin in Children

OBJECTIVES

Moxifloxacin is not approved by the US Food and Drug Administration for pediatric use. Although its use might be indicated under certain conditions, data regarding its safety and tolerability in pediatric patients are limited. The primary objective of this study was to evaluate the safety of systemic moxifloxacin therapy in children.

METHODS

We conducted a retrospective observational study of patients aged <18 years who received oral or intravenous moxifloxacin at our institution between January 2011 and July 2016. Patient demographics, clinical characteristics, indication for moxifloxacin use, and adverse events (AEs) were extracted via chart review. The attribution of AEs to moxifloxacin use was adjudicated in consultation with a pediatric infectious disease (ID) pharmacist.

RESULTS

We identified 221 patients who received 300 courses of moxifloxacin. The average age at moxifloxacin initiation was 10.4 years. One or more AEs occurred during 195 (65%) of the courses. Of the 463 distinct AEs, 46 (9.9%) were attributed to moxifloxacin. AEs attributed to moxifloxacin included corrected QT interval (QTc) prolongation (18 [6%] courses), transaminase level elevation (7 [2.3%] courses), and increased bilirubin level (3 [1%] courses). AEs led to moxifloxacin discontinuation in 18 (6%) courses. ID consultation was associated with QTc (P < .001) and transaminase (P = .002) monitoring.

CONCLUSIONS

AEs that occur during pediatric moxifloxacin therapy are relatively common but rarely serious enough to require premature discontinuation. The drug might be used safely in most children with monitoring, including evaluation for QTc prolongation, and guidance from ID specialists.

Use of Generic Medicines

The government is committed to make healthcare affordable as stated in the National Health Policy 2017. An estimated 94 million people in India are pushed into poverty due to expenditure on healthcare. About two thirds of the expenditure is incurred on medicines. Generic medicines are as effective as branded medicines. The initiative of the government and Medical Council of India by making it mandatory for doctors to write generic medicines has raised many concerns related to generic drugs availability and quality. Experience in the USA and Canada support the argument in favor of generic medicine. India is the main supplier of the generic medicines to the USA. There is a need to curtail inducement by pharmaceutical companies to promote their branded drugs as is being done in the USA. The government needs to make generic drugs easily available, strengthen quality control and educate doctors on benefits of using generic drugs.

Immunomodulatory activity of glycodelin: implications in allograft rejection

Glycodelin is an immunomodulator, indispensable for the maintenance of pregnancy in humans. The glycoprotein induces apoptosis in activated CD4⁺ T cells, monocytes and natural killer (NK) cells, and suppresses the activity of cytotoxic T cells, macrophages and dendritic cells. This study explores the immunosuppressive property of glycodelin for its possible use in preventing graft rejection. Because glycodelin is found only in certain primates, the hypothesis was investigated in an allograft nude mouse model. It is demonstrated that treatment of alloactivated mononuclear cells with glycodelin thwarts graft rejection. Glycodelin decreases the number of activated CD4⁺ and CD8⁺ cells and down-regulates the expression of key proteins known to be involved in graft demise such as granzyme-B, eomesodermin (EOMES), interleukin (IL)-2 and proinflammatory cytokines [tumour necrosis factor (TNF)-α and IL-6], resulting in a weakened cell-mediated immune response. Immunosuppressive drugs for treating allograft rejection are associated with severe side effects. Glycodelin, a natural immunomodulator in humans, would be an ideal alternative candidate.

Pharmacophore modelling, virtual screening and molecular docking studies on PLD1 inhibitors

Lipid metabolism plays a significant role in influenza virus replication and subsequent infection. The regulatory mechanism governing lipid metabolism and viral replication is not properly understood to date, but both Phospholipase D (PLD1 and PLD2) activities are stimulated in viral infection. In vitro studies indicate that chemical inhibition of PLD1 delays viral entry and reduction of viral loads. The current study reports a three-dimensional pharmacophore model based on 35 known PLD1 inhibitors. A sub-set of 25 compounds was selected as the training set and the remaining 10 compounds were kept in the test set. One hundred and twelve pharmacophore models were generated; a six-featured pharmacophore model (AADDHR.57) with survival score (2.69) produced a statistically significant three-dimensional quantitative structure-activity relationship model with r² = 0.97 (internal training set), r² = 0.71 (internal test set) and Q² = 0.64. The predictive power of the pharmacophore model was validated with an external test set (r² = 0.73) and a systematic virtual screening work-flow was employed showing an enrichment factor of 23.68 at the top 2% of the dataset (active and decoys). Finally, the model was used for screening of the filtered PubChem database to fetch molecules which can be proposed as potential PLD1 inhibitors for blocking influenza infection.

Mycoplasma hominis Empyema in an 18-Year-old Stem Cell and Lung Transplant Recipient: Case Report and Review of the Literature

Mycoplasma hominis has been identified as a rare cause of respiratory infections in immunocompromised adults. Here, we describe a case of Mycoplasma hominis empyema in an 18-year-old immunocompromised patient with a review of the literature highlighting diagnostic challenges associated with this infection.

Hydrogeological typologies of the Indo-Gangetic basin alluvial aquifer, South Asia

The Indo-Gangetic aquifer is one of the world's most important transboundary water resources, and the most heavily exploited aquifer in the world. To better understand the aquifer system, typologies have been characterized for the aquifer, which integrate existing datasets across the Indo-Gangetic catchment basin at a transboundary scale for the first time, and provide an alternative conceptualization of this aquifer system. Traditionally considered and mapped as a single homogenous aquifer of comparable aquifer properties and groundwater resource at a transboundary scale, the typologies illuminate significant spatial differences in recharge, permeability, storage, and groundwater chemistry across the aquifer system at this transboundary scale. These changes are shown to be systematic, concurrent with large-scale changes in sedimentology of the Pleistocene and Holocene alluvial aquifer, climate, and recent irrigation practices. Seven typologies of the aquifer are presented, each having a distinct set of challenges and opportunities for groundwater development and a different resilience to abstraction and climate change. The seven typologies are: (1) the piedmont margin, (2) the Upper Indus and Upper-Mid Ganges, (3) the Lower Ganges and Mid Brahmaputra, (4) the fluvially influenced deltaic area of the Bengal Basin, (5) the Middle Indus and Upper Ganges, (6) the Lower Indus, and (7) the marine-influenced deltaic areas.

Apolipoprotein A-I in Labeo rohita: Cloning and functional characterisation reveal its broad spectrum antimicrobial property, and indicate significant role during ectoparasitic infection

Apolipoprotein A-I (ApoA-I) is the most abundant and multifunctional high-density lipoprotein (HDL) having a major role in lipid transport and potent antimicrobial activity against a wide range of microbes. In this study, a complete CDS of 771 bp of Labeo rohita (rohu) ApoA-I (LrApoA-I) encoding a protein of 256 amino acids was amplified, cloned and sequenced. Tissue specific transcription analysis of LrApoA-I revealed its expression in a wide range of tissues, with a very high level of expression in liver and spleen. Ontogenic study of LrApoA-I expression showed presence of transcripts in milt and 3 h post-fertilization onwards in the larvae. The expression kinetics of LrApoA-I was studied upon infection with three different types of pathogens to elucidate its functional significance. Its expression was found to be up-regulated in the anterior kidney of L. rohita post-infection with Aeromonas hydrophila. Similarly following poly I:C (poly inosinic:cytidylic) stimulation, the transcript levels increased in both the anterior kidney and liver tissues. Significant up-regulation of LrApoA-I expression was observed in skin, mucous, liver and anterior kidney of the fish challenged with the ectoparasite Argulus siamensis. Immunomodulatory effect of recombinant LrApoA-I (rApoA-I) produced in Escherichia coli was demonstrated against A. hydrophila challenge in vivo. L. rohita administered with rApoA-I at a dose of 100 μg exhibited significantly higher protection (∼55%) upon challenge with A. hydrophila 12 h post-administration of the protein, in comparison to that observed in control group, along with higher level of expression of immune-related genes. The heightened expression of ApoA-I observed post-infection reflected its involvement in immune responses against a wide range of infections including bacterial, viral as well as parasitic pathogens. Our results also suggest the possibility of using rApoA-I as an immunostimulant, particularly rendering protection against A. hydrophila.

Systematic review of clinical outcomes after prophylactic surgery

Introduction Prophylactic appendicectomy is performed prior to military, polar and space expeditions to prevent acute appendicitis in the field. However, the risk-benefit ratio of prophylactic surgery is controversial. This study aimed to systematically review the evidence for prophylactic appendicectomy. It is supplemented by a clinical example of prophylactic surgery resulting in life-threatening complications. Methods A systematic review was performed using MEDLINE(®) and the Cochrane Central Register of Controlled Trials. Keyword variants of 'prophylaxis' and 'appendicectomy' were combined to identify potential papers for inclusion. Papers related to prophylactic appendicectomy risks and benefits were reviewed. Results Overall, 511 papers were identified, with 37 papers satisfying the inclusion criteria. Nine reported outcomes after incidental appendicectomy during concurrent surgical procedures. No papers focused explicitly on prophylactic appendicectomy in asymptomatic patients. The clinical example outlined acute obstruction secondary to adhesions from a prophylactic appendicectomy. Complications after elective appendicectomy versus the natural history of acute appendicitis in scenarios such as polar expeditions or covert operations suggest prophylactic appendicectomy may be appropriate prior to extreme situations. Nevertheless, the long-term risk of adhesion related complications render prophylactic appendicectomy feasible only when the short-term risk of acute appendicitis outweighs the long-term risks of surgery. Conclusions Prophylactic appendicectomy is rarely performed and not without risk. This is the first documented evidence of long-term complications following prophylactic appendicectomy. Surgery should be considered on an individual basis by balancing the risks of acute appendicitis in the field with the potential consequences of an otherwise unnecessary surgical procedure in a healthy patient.

EXPLORING HEALTHCARE PERSPECTIVES OF BURMESE CHIN REFUGEES

The objective of this study was to understand the Burmese Chin refugees' experiences with and perspectives on the United States healthcare system. Using a mixed-methods study design, a survey was distributed and focus groups were conducted. Thirty-seven surveys were completed. Five major themes emerged from the focus group discussions: time, language barriers, relationships with healthcare providers, traditional medicine, and adolescents'roles in their community. Refugee healthcare perspectives give health providers insights on how to work towards providing culturally appropriate care.

Four pro-inflammatory cytokines of rohu (Labeo rohita) during early developmental stages, their tissue distribution and expression by leucocytes upon in-vitro stimulation

Cytokines are important components of both adaptive and innate immunity, and are required to initiate and regulate immune responses following infection. The ontogeny and tissue specific distribution of four pro-inflammatory cytokines, interleukin-6 (IL-6), tumor necrosis factor α (TNF-α), IL-8 and IL-1β in rohu (Labeo rohita), and their responses by leucocytes from anterior-kidney/head-kidney (HKLs), spleen (SPLs) and peripheral blood (PBLs) following stimulation with concanavalin A (ConA), ConA with phorbol 12-myristate 13-acetate (ConA/PMA) and formalin-killed Aeromonas hydrophila cells (FAH) were studied. In ontogeny study, mRNA levels of IL-6 and IL-1β were evident in unfertilized egg stages of L. rohita whereas IL-8 and TNF-α transcripts were found from 1 to 3 h post-fertilization (hpf) onwards till day 15 post-fertilization, respectively. Basal level of all four cytokines was observed in all twelve tissues (eye, brain, heart, gill, anterior kidney, posterior kidney, spleen, liver, skin, muscle, hindgut and foregut) of L. rohita juveniles. Expression levels of IL-6 and IL-8 were found to be the highest in liver and heart tissues, respectively, while TNF-α transcripts were high in anterior kidney and liver tissues. Transcripts of IL-1β showed high expression in muscle, heart and spleen. Upon in vitro stimulation of leucocytes, there was variable up-regulation of all the four cytokines following different treatments throughout the experimental time period. Induction of cytokines was more pronounced in PBLs stimulated with FAH compared to other stimuli. However, an up-regulated IL-8 expression was evident in all the leucocytes following stimulation with FAH thus indicating IL-8 could be used as an indicator or indirect marker to monitor vaccine status or health status of L. rohita during bacterial infection.

Parental Leave Policies and Pediatric Trainees in the United States

BACKGROUND

The American Academy of Pediatrics (AAP) states that each residency program should have a clearly delineated, written policy for parental leave. Parental leave has important implications for trainees' ability to achieve their breastfeeding goals.

OBJECTIVE

This study aimed to measure the knowledge and awareness among members of the AAP Section on Medical Students, Residents, and Fellowship Trainees (SOMSRFT) regarding parental leave.

METHODS

An online survey was emailed to SOMSRFT members in June 2013. Quantitative data are presented as percentage of respondents. Awareness of leave policies was analyzed based on having children and the sex of respondents.

RESULTS

Nine hundred twenty-seven members responded to the survey. Among those with children, 40% needed to extend the duration of their training in order to have longer maternity leave, 44% of whom did so in order to breastfeed longer. Thirty percent of respondents did not know if their program had a written, accessible policy for parental leave. Trainees without children and men were more unaware of specific aspects of parental leave such as eligibility for the Family Medical Leave Act as compared to women and those with children.

CONCLUSION

Despite the fact that United States national policies support parental leave during pediatrics training, and a majority of programs comply, trainees' awareness regarding these policies needs improvement.

"Frustrated," "depressed," and "devastated" pediatric trainees: US academic medical centers fail to provide adequate workplace breastfeeding support

BACKGROUND

Exclusive breastfeeding (EBF) is recommended until about 6 months of age. Pediatricians are at the forefront of encouraging mothers to achieve this goal, yet pediatricians who parent during their training may face substantial barriers in achieving their own breastfeeding goals.

OBJECTIVES

This study aimed to assess breastfeeding support available to US pediatricians in training and the effect of trainees' personal experiences on their attitude toward breastfeeding.

METHODS

An online survey was emailed to American Academy of Pediatrics Section on Medical Students, Residents, and Fellowship Trainees members.

RESULTS

There were 927 respondents, of which 421 had children and 346 breastfed their children. Almost 80% agreed that 6 months is the ideal duration for EBF. One in 4 did not have access to or were not aware of a private room to express milk or breastfeed. Forty percent needed to extend the duration of their training for a longer maternity leave, with breastfeeding a factor for longer leave among 44%. One in 4 did not meet their breastfeeding duration goal, and 1 in 3 did not meet their goal for EBF. Negative emotions were common among those not meeting goals. Ninety-two percent felt that their or their partner's experience with breastfeeding affected their clinical interaction with patients' mothers.

CONCLUSION

A majority of respondents cited problems with breastfeeding support during training, and many failed to meet their intended goals. Not meeting personal breastfeeding goals was associated with negative emotions and influenced how they counsel about breastfeeding as a result of personal and often negative attitudes.

Large-scale discovery of novel genetic causes of developmental disorders

Despite three decades of successful, predominantly phenotype-driven discovery of the genetic causes of monogenic disorders, up to half of children with severe developmental disorders of probable genetic origin remain without a genetic diagnosis. Particularly challenging are those disorders rare enough to have eluded recognition as a discrete clinical entity, those with highly variable clinical manifestations, and those that are difficult to distinguish from other, very similar, disorders. Here we demonstrate the power of using an unbiased genotype-driven approach to identify subsets of patients with similar disorders. By studying 1,133 children with severe, undiagnosed developmental disorders, and their parents, using a combination of exome sequencing and array-based detection of chromosomal rearrangements, we discovered 12 novel genes associated with developmental disorders. These newly implicated genes increase by 10% (from 28% to 31%) the proportion of children that could be diagnosed. Clustering of missense mutations in six of these newly implicated genes suggests that normal development is being perturbed by an activating or dominant-negative mechanism. Our findings demonstrate the value of adopting a comprehensive strategy, both genome-wide and nationwide, to elucidate the underlying causes of rare genetic disorders.

A structural insight into hydroxamic acid based histone deacetylase inhibitors for the presence of anticancer activity

Histone deacetylase inhibitors (HDACi) have been actively explored as anti-cancer agents due to their ability to prevent deacetylation of histones, resulting in uncoiling of chromatin and stimulation of a range of genes associated in the regulation of cell survival, proliferation, differentiation and apoptosis. During the past several years, many HDACi have entered pre-clinical or clinical research as anti-cancer agents with satisfying results. Out of these, more than 8 novel hydroxamic acid based HDACi i.e., belinostat, abexinostat, SB939, resminostat, givinostat, quisinostat, pentobinostat, CUDC-101 are in clinical trials and one of the drug vorinostat (SAHA) has been approved by US FDA for cutaneous T-cell lymphoma (CTCL). It is clear from the plethora of new molecules and the encouraging results from clinical trials that this class of HDAC inhibitors hold a great deal of promise for the treatment of a variety of cancers. In this review, we classified the hydroxamic acid based HDACi on the basis of their structural features into saturated, unsaturated, branched, un-branched and 5, 6-membered cyclic ring linker present between zinc binding group and connecting unit. The present article enlists reports on hydroxamic acid based HDACi designed and developed using concepts of medicinal chemistry, demonstrating that hydroxamate derivatives represent a versatile class of compounds leading to novel imaging and therapeutic agents. This article will also provide a complete insight into various structural modifications required for optimum anticancer activity.

Cross-sectional evaluation of awareness of prevention of dental caries among general pediatricians in ghaziabad district, India

Background:

Oral diseases are largely preventable and it is hoped that with the early exposure to oral health-care activities, the prevalence of oral diseases will be reduced in children and they would be more receptive to dental services. Aim: The present study evaluated the awareness of prevention of dental caries among pediatricians in Ghaziabad district, India.

Subjects and Methods:

A cross-sectional survey was undertaken among the pediatricians in Ghaziabad district, India. Total subjects including in the survey were 88 pediatricians, through systemic random sampling. Both the gender was including Male-37.8% (35/88) and Female-62.2% (53/88). Pre-tested, structured and self administered questionnaire was used in the survey and data analysis was done by using ‘SPSS’ software version 16.0 (IBM, United States).

Results:

Our study indicated that most of the pediatricians in Ghaziabad district had moderate knowledge 39.7% (35/88), followed by good knowledge 36.5% (32/88) and poor knowledge 23.8% (21/88) about dental caries. Practice guidelines and opinions of pediatricians in the survey were moderate 64.7% (57/88) in about more than half, followed by poor 23.8% (21/88) and followed by good 11.5% (10/88). The attitude for prevention of dental caries was positive in almost everybody 81.8% (72/88).

Conclusion:

The present survey concluded that pediatricians in Ghaziabad district, India had a good attitude and practices, but had moderate knowledge and lacked proper awareness about dental caries.

Immune responses and protective efficacy of recombinant outer membrane protein R (rOmpR)-based vaccine of Aeromonas hydrophila with a modified adjuvant formulation in rohu (Labeo rohita)

Despite the importance and success of developing a candidate vaccine against Aeromonas hydrophila infection in fish, little is known about the molecular mechanisms of the vaccine-induced immunoprotection in Indian major carp, Labeo rohita, primarily due to lack of information on most of the immune related genes of the species. In this study, a novel candidate antigen recombinant outer membrane protein R (rOmpR) of A. hydrophila was evaluated as a vaccine candidate along with a modified adjuvant formulation. Protective efficacy of the rOmpR immunization was assessed in terms of survival against A. hydrophila challenge as well as modulation of immune response in vaccinated fish after 1, 3, 6, 12, 24, 72 h and 10 days post-injection (using immune gene expression analysis) and 10, 28, 56 and 140 days post-injection (serum immune parameter analysis). The generated immune response was compared with a formalin-killed A. hydrophila antigen preparation using mineral oil only and modified adjuvant alone. We report a variable up-regulation of the immune-related genes viz., lysozyme G, complement factor 4, immunoglobulin M, β2-microglobulin, major histocompatibility complex I and II, and interleukin-1β in anterior kidney and spleen tissues at early time points post-immunization in all the groups, when compared to the control fish. The vaccinated fish also showed an increase in serum natural hemolysin titer, lysozyme and myeloperoxidase activities, and antibody titer irrespective of vaccine formulations as compared to control fish on days 10, 28 and 56. However, the increase in the serum parameters was more pronounced on day 140 in rOmpR-modified adjuvant injected group, indicating the modulatory role of this new vaccine formulation. Upon challenge with live A. hydrophila on days 56 and 140 post-immunization, significantly reduced percent mortality was noted in the group immunized with modified adjuvant based rOmpR vaccine formulation. Taken together, our results suggest that rOmpR along with modified adjuvant could potentially be used as a vaccine formulation to handle A. hydrophila infection on a long-term basis.

A Systematic Review of Nutritional Supplementation in HIV-Infected Children in Resource-Limited Settings

BACKGROUND

In resource-limited settings, malnutrition is the major cause of death in young children, but the precise benefits of nutritional supplementation for HIV-infected children are not well understood.

METHODS

Two researchers reviewed studies conducted in low- or middle-income countries that involved macro- and micronutrient supplementation in HIV-infected individuals ≤18 years.

RESULTS

Fifteen studies focused on micronutrients, including vitamin A, zinc, multivitamins, and multiple-micronutrient supplementation. The 8 macronutrient studies focused on ready-to-use foods (4 studies), spirulina, whey protein, general food rations, and F75 and F100 starter formulas. Vitamin A was associated with improved mortality rates, ranging from 28% to 63%. Multiple-micronutrient supplementations were not associated with improvement of measured health outcomes. Ready-to-use foods were associated with improvement in certain anthropometrics.

CONCLUSION

Periodic vitamin A supplementation is associated with reduced mortality. Macronutrient supplementation is linked to improved anthropometrics. More research is needed to determine how nutritional supplementation benefits this particularly vulnerable population.

ERRβ signalling through FST and BCAS2 inhibits cellular proliferation in breast cancer cells

Background:

The overexpression of oestrogen-related receptor-β (ERRβ) in breast cancer patients is correlated with improved prognosis and longer relapse-free survival, and the level of ERRβ mRNA is inversely correlated with the S-phase fraction of cells from breast cancer patients.

Methods:

Chromatin immunoprecipitation (ChIP) cloning of ERRβ transcriptional targets and gel supershift assays identified breast cancer amplified sequence 2 (BCAS2) and Follistatin (FST) as two important downstream genes that help to regulate tumourigenesis. Confocal microscopy, co-immunoprecipitation (CoIP), western blotting and quantitative real-time PCR confirmed the involvement of ERRβ in oestrogen signalling.

Results:

Overexpressed ERRβ induced FST-mediated apoptosis in breast cancer cells, and E-cadherin expression was also enhanced through upregulation of FST. However, this anti-proliferative signalling function was challenged by ERRβ-mediated BCAS2 upregulation, which inhibited FST transcription through the downregulation of β-catenin/TCF4 recruitment to the FST promoter. Interestingly, ERRβ-mediated upregulation of BCAS2 downregulated the major G1-S transition marker cyclin D1, despite the predictable oncogenic properties of BCAS2.

Interpretation:

Our study provides the first evidence that ERRβ, which is a coregulator of ERα also acts as a potential tumour-suppressor molecule in breast cancer. Our current report also provides novel insights into the entire cascade of ERRβ signalling events, which may lead to BCAS2-mediated blockage of the G1/S transition and inhibition of the epithelial to mesenchymal transition through FST-mediated regulation of E-cadherin. Importantly, matrix metalloprotease 7, which is a classical mediator of metastasis and E-cadherin cleavage, was also restricted as a result of ERRβ-mediated FST overexpression.

Do alpha deletions influence hydroxyurea response in thalassemia intermedia?

Thalassemia intermedia patients show variable phenotypes. Hydroxyurea (HU) may benefit some of the thalassemia intermedia cases (1), however, the parameters influencing the response to HU have not been reported. In this study, the molecular parameters, alpha-globin and beta-globin genotype and the Xmn I polymorphism, were correlated with the HU response. Twenty patients with thalassemia intermedia were given HU (10-20 mg/kg) and responses were evaluated over a one year period. Twelve patients (60%) showed a good response to therapy with a significant increase in Hb and HbF levels and with elimination of the transfusion requirement in four patients. Four out of the twelve (33%) patients were positive for -alpha(3.7) deletions whereas none of the 8 non-responders were positive for alpha deletions. One each of the responders and non-responders were positive for alpha alpha alpha(anti-3.7) triplication. Three (25%) responsive and one non-responsive patients were homozygous for the IVS1-1 (G-->T) mutation. Three of the responsive patients with alpha deletions were also homozygous positive for Xmn I polymorphism. Thus, in addition to acting in synergy with the XmnI polymorphism, alpha deletions may be an independent factor predicting good response to HU in thalassemia intermedia, although this needs to be confirmation in larger studies.