A cathodoluminescence study of InP/InGaP axially heterostructured NWs for tandem solar cells

Axially heterostructured nanowires (NWs) constitute a promising platform for advanced electronic and optoelectronic nanodevices. The presence of different materials in these NWs introduces a mismatch resulting in complex strain distributions susceptible of changing the band gap and carrier mobility. The growth of these NWs presents challenges related to the reservoir effect in the catalysts droplet that affect to the junction abruptness, and the occurrence of undesired lateral growth creating core-shell heterostructures that introduce additional strain. We present herein a cathodoluminescence (CL) analysis on axially heterostructured InP/InGaP NWs with tandem solar cell structure. The CL is complemented with micro Raman, micro photoluminescence (PL), and high resolution transmission electron microscopy measurements. The results reveal the zinc blende structure of the NWs, the presence of a thin InGaP shell around the InP bottom cell, along with its associated strain, and the doping distribution.

Achievement of Target Gain Larger than Unity in an Inertial Fusion Experiment

On December 5, 2022, an indirect drive fusion implosion on the National Ignition Facility (NIF) achieved a target gain G_{target} of 1.5. This is the first laboratory demonstration of exceeding "scientific breakeven" (or G_{target}>1) where 2.05 MJ of 351 nm laser light produced 3.1 MJ of total fusion yield, a result which significantly exceeds the Lawson criterion for fusion ignition as reported in a previous NIF implosion [H. Abu-Shawareb et al. (Indirect Drive ICF Collaboration), Phys. Rev. Lett. 129, 075001 (2022)PRLTAO0031-900710.1103/PhysRevLett.129.075001]. This achievement is the culmination of more than five decades of research and gives proof that laboratory fusion, based on fundamental physics principles, is possible. This Letter reports on the target, laser, design, and experimental advancements that led to this result.

Person-centered strategies for delivering TB diagnostic services in Lima, Peru

SETTING

Lima, Peru.

OBJECTIVE

To close the gap in TB diagnosis, TB diagnostic services must match care-seeking preferences. We sought to identify preferred strategies for delivering TB diagnostic services and to determine whether preferences differ among demographic groups.

DESIGN

During May 2022-January 2023, we recruited adults who recently initiated treatment for pulmonary TB. We used an object-case best-worst scaling instrument to assess the desirability of nine hypothetical strategies for delivering TB diagnostic services. A t-test was used to assess differences in preference scores between groups.

RESULTS

Among 150 participants, the strategies with the highest preference scores were an integrated mobile unit offering screening for multiple conditions, expedited attention at the health center, and home-based screening. These were strongly preferred by 42%, 25%, and 27% of participants, respectively, and 80% of participants strongly preferred at least one of the three. Expedited attention at the health center scored more highly among people who experienced >2 months delay in TB diagnosis compared to those who experienced a more rapid diagnosis (0.37 ± 0.06 vs. 0.17 ± 0.06; P = 0.031).

CONCLUSION

Providing person-centered TB diagnostic services at diverse access points could help reach different populations, which could promote early diagnosis and help close the diagnosis gap.

Latent TB and depressive symptoms in household contacts of persons with active TB

BACKGROUND: Depression is common among persons with TB and is associated with poor clinical outcomes. However, little is known about the relationship between latent TB infection (LTBI) and depression. We assessed the association between LTBI and depressive symptoms among household contacts (HHCs) of patients receiving TB treatment.METHODS: We enrolled 1,009 HHCs of 307 patients receiving TB treatment in Lima, Peru, during 2016-2018. At enrollment, HHC LTBI status was assessed using the interferon-gamma release assay (IGRA). Depressive symptoms were assessed at baseline and 12 months later using the Patient Health Questionnaire-9 (PHQ-9) with a cut-off of ≥5. We used logistic regression to estimate the odds ratio (OR) for PHQ-9 ≥5, comparing HHCs with and without baseline LTBI.RESULTS: Among 921 HHCs, 374 (41.0%) had LTBI at baseline, and 69 (12.4%) of 567 HHCs had PHQ-9 ≥5. Compared to HHCs without LTBI at enrollment, those with LTBI had almost two times the odds of PHQ-9 ≥5 at follow-up after controlling for potential confounders (adjusted OR 1.93, 95% CI 1.09-3.39); this association was driven by greater severities of depressive symptoms.CONCLUSION: HHCs with LTBI had increased odds of depressive symptoms 1 year later. This population may benefit from mental health screening and interventions integrated into TB programs.

Preeclampsia and risk of maternal pulmonary hypertension at high altitude in Bolivia

Women with a history of preeclampsia (PE) have a greater risk of pulmonary arterial hypertension (PAH). In turn, pregnancy at high altitude is a risk factor for PE. However, whether women who develop PE during highland pregnancy are at risk of PAH before and after birth has not been investigated. We tested the hypothesis that during highland pregnancy, women who develop PE are at greater risk of PAH compared to women undergoing healthy highland pregnancies. The study was on 140 women in La Paz, Bolivia (3640m). Women undergoing healthy highland pregnancy were controls (C, n = 70; 29 ± 3.3 years old, mean±SD). Women diagnosed with PE were the experimental group (PE, n = 70, 31 ± 2 years old). Conventional (B- and M-mode, PW Doppler) and modern (pulsed wave tissue Doppler imaging) ultrasound were applied for cardiovascular íííassessment. Spirometry determined maternal lung function. Assessments occurred at 35 ± 4 weeks of pregnancy and 6 ± 0.3 weeks after birth. Relative to highland controls, highland PE women had enlarged right ventricular (RV) and right atrial chamber sizes, greater pulmonary artery dimensions and increased estimated RV contractility, pulmonary artery pressure and pulmonary vascular resistance. Highland PE women had lower values for peripheral oxygen saturation, forced expiratory flow and the bronchial permeability index. Differences remained 6 weeks after birth. Therefore, women who develop PE at high altitude are at greater risk of PAH before and long after birth. Hence, women with a history of PE at high altitude have an increased cardiovascular risk that transcends the systemic circulation to include the pulmonary vascular bed.

Establishment of patient-derived tumor organoids to functionally inform treatment decisions in metastatic colorectal cancer

BACKGROUND

Metastatic colorectal cancer (mCRC) patients tend to have modest benefits from molecularly driven therapeutics. Patient-derived tumor organoids (PDTOs) represent an unmatched model to elucidate tumor resistance to therapy, due to their high capacity to resemble tumor characteristics.

MATERIALS AND METHODS

We used viable tumor tissue from two cohorts of patients with mCRC, naïve or refractory to treatment, respectively, for generating PDTOs. The derived models were subjected to a 6-day drug screening assay (DSA) with a comprehensive pipeline of chemotherapy and targeted drugs against almost all the actionable mCRC molecular drivers. For the second cohort DSA data were matched with those from PDTO genotyping.

RESULTS

A total of 40 PDTOs included in the two cohorts were derived from mCRC primary tumors or metastases. The first cohort included 31 PDTOs derived from patients treated in front line. For this cohort, DSA results were matched with patient responses. Moreover, RAS/BRAF mutational status was matched with DSA cetuximab response. Ten out of 12 (83.3%) RAS wild-type PDTOs responded to cetuximab, while all the mutant PDTOs, 8 out of 8 (100%), were resistant. For the second cohort (chemorefractory patients), we used part of tumor tissue for genotyping. Four out of nine DSA/genotyping data resulted applicable in the clinic. Two RAS-mutant mCRC patients have been treated with FOLFOX-bevacizumab and mitomycin-capecitabine in third line, respectively, based on DSA results, obtaining disease control. One patient was treated with nivolumab-second mitochondrial-derived activator of caspases mimetic (phase I trial) due to high tumor mutational burden at genotyping, experiencing stable disease. In one case, the presence of BRCA2 mutation correlated with DSA sensitivity to olaparib; however, the patient could not receive the therapy.

CONCLUSIONS

Using CRC as a model, we have designed and validated a clinically applicable methodology to potentially inform clinical decisions with functional data. Undoubtedly, further larger analyses are needed to improve methodology success rates and propose suitable treatment strategies for mCRC patients.

SoilFract: A mechanistic model accounting for the fate of exogenous organic matter in soil carbon and nitrogen cycles

As its use in agriculture grows, the fate of digestate in soil raises concerns on many different levels. In particular, the degradability of its organic matter when spread on soil is still an ongoing topic. In an effort to better understand the processes and dynamics of digestate soil incubation, C and N mineralization kinetics obtained in 358 days long laboratory incubations during decomposition of digestates were simulated using a dynamic model. The model includes twelve compartments related through processes including 18 parameters. The main novelty of this model is the use of accessibility-related variables to describe the fate of exogenous organic matter in soil, thus enabling a detailed understanding of its outcome in soil. Model calibration on cattle manure digestate incubation resulted in the estimation of parameter values. The newly calibrated model was then tested on an energy crop digestate incubation experiment. The model was able to reproduce accurately the experimental behavior of most variables.

Effects of intravenous lysine acetylsalicylate versus oral aspirin on platelet responsiveness in patients with ST-segment elevation myocardial infarction

Background

Prasugrel and ticagrelor, new P2Y12-ADP receptor antagonists, are associated with greater pharmacodynamic inhibition and reduction of cardiovascular events in patients with an acute coronary syndrome. However, evidence is lacked about the effects of achieving faster and stronger cyclooxygenase inhibition with intravenous lysine acetylsalicylate (LA) compared to oral aspirin on prasugrel inhibited platelets in patients with an ST-segment elevation myocardial infarction (STEMI).

Methods

This is a prospective, randomized, multicenter, open platelet function study conducted. STEMI patients were randomly assigned to receive a loading dose (LD) of intravenous LA 450mg plus oral ticagrelor 180mg, or LD of aspirin 300mg plus ticagrelor 180mg orally. Platelet function was evaluated at baseline, 30 min, 1h, and 24h using multiple electrode aggregometry and vasodilator-stimulated phosphoprotein phosphorylation (VASP). The primary endpoint of the study is the inhibition of platelet aggregation after arachidonic acid (AA) 1.5mM at 30 min. Secondary endopoints are the inhibition of platelet aggregation after AA baseline and at 1h, and 24h, and measurement of aggregation with other platelet test (ADP, collagen and VASP).

Results

A total of 32 STEMI patients were randomized (16 LA, 16 aspirin). The inhibition of platelet aggregation after AA 1.5 mM at 30 min was greater in subjects treated with LA compared with aspirin: 166 vs. 412 respectively, p=0.001. This differential effect was observed at 1 hour (p=0.01), but not at 24 hours. Subjects treated with LA presented less variability and faster and greater inhibition of platelet aggregation with AA compared with aspirin (Figure 1).

Conclusions

The administration of intravenous LA resulted in a significantly reduction of platelet reactivity compared to oral aspirin on ticagrelor inhibited platelets in patients with STEMI. Loading dose of LA achieves an earlier platelet inhibition, and with less variability than aspirin.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): This study was supported by the CTU-SCReN (Clinical Trial Unit – Spanish Clinical Research Network) from San Carlos University Hospital (Madrid, Spain), financed by the ISCII (Project PI16/00191)

Lawson Criterion for Ignition Exceeded in an Inertial Fusion Experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion.

Negative SA-VA difference during entrainment of a supraventricular tachycardia: a new criterion for the diagnosis of focal atrial tachycardia

Funding Acknowledgements

Type of funding sources: None.

Introduction

Ventricular overdrive pacing during tachycardia is one of the most common and useful maneuvers to assess de differential diagnosis of supraventricular tachycardia (SVT). Focal atrial tachycardia (FAT) usually presents long ventriculo-atrial (VA) interval, which is a passive interval since FAT is not an atrio-ventricular reentry. Therefore, during ventricular entrainment of a FAT, the stimulus-atrial (SA) interval will depend solely on the retrograde VA conduction time, if retrograde conduction exists. This retrograde conduction time is usually shorter than the VA Interval during tachycardia, thus being able to cause a negative SA-VA difference. This does not occur in other types of SVT, where the SA-VA difference helps to differential diagnosis, but positive values have been described.

Purpose

Our aim was to analyze whether the SA-VA value discriminates FAT from the other types of SVT, in patients with SVT and VA conduction when stimulating the ventricle during tachycardia.

Methods

Multicenter data of SVT entrainment were collected retrospectively, including FAT, atrioventricular nodal reentry tachycardia (AVNRT), and atrioventricular reciprocating tachycardia (AVRT). The numeric value of SA-VA difference was calculated for each case. The best SA-VA cut-off point for the diagnosis of TAF was determined, evaluating the sensitivity and specificity of this value for the diagnosis of TAF with respect to the gold standard (classical criteria).

Results

Continuous ventricular pacing during tachycardia succeeded in accelerating the atrium to the pacing rate in 80 cases out of the total studied cases: 32 (40%) AVNRT, 28 (35%) AVRT and 20 (25%) FAT. All FAT cases had a negative SA-VA value and all AVNRT and AVRT cases obtained positive SA-VA (Figure 1). SA-VA value lower than 0 ms was the best cut-off point (using ROC curve, Figure 2) with an area under the curve of 1. SA-VA difference lower than 0 ms (or negative SA-VA difference) showed 100% sensitivity and specificity for the diagnosis of FAT.

Conclusions

Negative SA-VA difference is a new and accurate criterion for the diagnosis of focal atrial tachycardia.

Integrated screening and testing for TB and COVID-19 in Peru

We describe the experience of integrating COVID-19 screening and testing into a mobile TB screening unit in Lima, Peru. All attendees received chest radiographs, which were analysed using CAD4TB and CAD4COVID; Xpert MTB/RIF Ultra was used to test for TB, and antibody and polymerase chain reaction (PCR) for SARS-CoV-2. One Xpert-positive TB case was diagnosed per 168 people screened, one person with SARS-CoV-2 antibodies per 3 people screened, and one PCR-confirmed SARS-CoV-2 infection per 8 people screened. Integrated screening can help to avoid delays in the diagnosis of both TB and COVID-19.

Optical Fiber Time Delay Comparison Between NIST and LAMETRO

We describe the results of a bilateral measurement comparison of optical fiber time delay between the National Institute of Standards and Technology (NIST, USA) and Laboratorio de Metrología, Instituto Costarricense de Electricidad (LAMETRO-ICE, Costa Rica), which was conducted on a single-mode optical fiber reference spool at wavelengths of 1310 nm and 1550 nm. The measurement results showed the largest difference to be less than 0.93 ns, which is within the combined standard uncertainty (coverage factor k = 1) for the measurement systems at the two laboratories.

Using AnABlast for intergenic sORF prediction in the Caenorhabditis elegans genome

Motivation

Short bioactive peptides encoded by small open reading frames (sORFs) play important roles in eukaryotes. Bioinformatics prediction of ORFs is an early step in a genome sequence analysis, but sORFs encoding short peptides, often using non-AUG initiation codons, are not easily discriminated from false ORFs occurring by chance.

Results

AnABlast is a computational tool designed to highlight putative protein-coding regions in genomic DNA sequences. This protein-coding finder is independent of ORF length and reading frame shifts, thus making of AnABlast a potentially useful tool to predict sORFs. Using this algorithm, here, we report the identification of 82 putative new intergenic sORFs in the Caenorhabditis elegans genome. Sequence similarity, motif presence, expression data and RNA interference experiments support that the underlined sORFs likely encode functional peptides, encouraging the use of AnABlast as a new approach for the accurate prediction of intergenic sORFs in annotated eukaryotic genomes.

Availability and implementation

AnABlast is freely available at http://www.bioinfocabd.upo.es/ab/. The C.elegans genome browser with AnABlast results, annotated genes and all data used in this study is available at http://www.bioinfocabd.upo.es/celegans.

Supplementary information

Supplementary data are available at Bioinformatics online.

Fusobacterium nucleatum persistence and risk of recurrence after preoperative treatment in locally advanced rectal cancer

BACKGROUND

Accumulating evidence has identified Fusobacterium as an important pathogenic gut bacterium associated with colorectal cancer. Nevertheless, only limited data exist about the role of this bacterium in locally advanced rectal cancer (LARC). In this study, we quantified Fusobacterium nucleatum in untreated and post-neoadjuvant chemoradiotherapy (nCRT) samples from LARC patients and investigated its association with therapy response and survival.

PATIENTS AND METHODS

A total of 254 samples from 143 patients with rectal adenocarcinomas were analyzed for the presence and abundance of F. nucleatum using RNA in situ hybridization and digital image analysis. Assay accuracy was determined using infected cell lines and tumor samples with available quantitative PCR data. We studied the impact of F. nucleatum load on pathologic complete response and relapse-free survival. Treatment-induced changes were evaluated in paired pre- and post-nCRT samples (n = 71). Finally, tumor microenvironment changes during nCRT were assessed in paired samples (n = 45) by immune contexture analysis.

RESULTS

F. nucleatum tissue levels by RNA in situ hybridization strongly correlated with quantitative PCR (r = 0.804, P < 0.001). F. nucleatum abundance was higher in untreated [median, 7.4; 95% confidence interval (3.7-16.2)] compared with treated [median, 1.6; 95% confidence interval (1.3-2.4)] tumors (P <0.001) with 58% (73/126) and 26% (22/85) positive tumors, respectively (P < 0.001). Baseline F. nucleatum levels were not associated with pathologic complete response. F. nucleatum positivity after nCRT, but not baseline status, significantly increased risk of relapse [hazard ratio = 7.5, 95% confidence interval (3.0-19.0); P < 0.001]. Tumors that turned F. nucleatum-negative after nCRT had a strong increase in CD8+ T cells post-nCRT (P < 0.001), while those that persisted F. nucleatum-positive after nCRT lacked CD8+ T cells induction in post-nCRT samples compared with baseline (P = 0.69).

CONCLUSION

F. nucleatum persistence post-nCRT is associated with high relapse rates in LARC, potentially linked to suppression of immune cytotoxicity.

Humic-like substances extracted from different digestates: First trials of lettuce biostimulation in hydroponic culture

Digestate valorization is a key challenge for the feasibility of Anaerobic Digestion plants. In this study, humic-like substances (HLS) extracted from two digestates (sewage sludge and manure) were used for the biostimulation of hydroponic cultures of Lactuca sativa (lettuce) at different doses and compared to a commercial reference of leonardite HLS. Aerial biomass increase averages ranged from 7 to 30 %, but the results presented a high coefficient of variation (around 20 %). The commercial reference did not present statistically significant biomass yield improvement. The application of manure digestate extract at the higher fulvic-like acids dose (4.6 mg/L of dissolved organic carbon) presented the best and most significant results compared to the blank (Hoagland's solution only). However, this result cannot be strictly dissociated from the supplementary amounts of nutrients brought by the extracts. Additionally, all the products presented low heavy metal content compared to the recent EU regulation for biostimulants (2019/1009). This preliminary study confirmed the interest of extracting HLS from two digestates for application as biostimulants, shedding light on a new perspective for digestate valorization.

Optical-Fiber Power Meter Comparison between NIST and LAMETRO

We describe the results of a comparison of reference standards between the National Institute of Standards and Technology (NIST-USA) and Laboratorio de Metrologia, Instituto Costarricense de Electricidad (LAMETRO-ICE, COSTA RICA) for optical fiber-based power measurements at wavelengths of 1310.0 nm, 1550.15 nm, and 1625.0 nm. We compare the laboratories' reference standards by means of a commercial temperature-controlled optical fiber power meter. Measurement results showed the largest difference of less than 5.8 parts in 103, which is within the combined standard (k=1) uncertainty for the two laboratories� reference standards.

The Test-Retest Reliability of a Clinically-Relevant Dual-Task Assessment in Healthy College Students

Purpose

The dual-task (DT) paradigm consists of concurrent administration of motor and cognitive tasks which may demonstrate improved measurement properties of the included tasks as compared to independent administration. Our study examined the test-retest reliability of a clinically-relevant DT assessment.

Methods

Our prospective cohort study included 60 (53.3% female) healthy, recreationally active college students (Age=20.5–1.34 years; Height=171.7–9.33 cm). Participants completed the Standardized Assessment of Concussion (SAC) and timed tandem gait (TTG) test concurrently for the DT assessment at two time points separated by a two-week test-retest interval. The SAC composite score (45 points) was calculated by summing the domain scores of immediate memory (30 points) which consisted of a 10-word list, concentration (5 points), and delayed recall (10 points). The TTG composite score was calculated by summing the mean time to complete the TTG during each SAC task (3 trials for immediate memory, up to 5 trials for the digits-backwards task, and one trial for the months in reverse order and delayed recall tasks). Mixed-model intraclass correlation coefficients (ICC[3,1]) with 95% confidence intervals were calculated to evaluate test-retest reliability between time points for the SAC and TTG composite scores.

Results

Mean SAC (39.4–3.80 vs. 39.6–3.49 points) and TTG (52.1–9.44 vs. 48.2–8.33 sec) composite scores were observed at time points 1 and 2, respectively. Moderate (ICC[3,1]=0.56 [0.26, 0.74]) and good (ICC[3,1]=0.88 [0.80, 0.93]) test-retest reliability were observed for the SAC and TTG composite scores, respectively.

Conclusion

Test-retest reliability for our DT assessment aligns with previously established values for independent administration of the SAC and TTG.

First fertilizing-value typology of digestates: A decision-making tool for regulation

Defined as the residue from anaerobic digestion (AD), digestate refers to a set of materials with varied biochemical compositions. The objective of this study was to establish a digestate typology according to its fertilizing-value with data from literature and internal unpublished databases. To establish a relatively big database allowing the application of advanced statistics, usual fertilizing-value parameters were used: dry matter, volatile solids, C/N, C/Organic-N, total N (TN), total ammoniacal nitrogen (TAN), TAN/TN, total P and total K. Statistical analysis was performed on a dataset of 91 raw digestates, 34 solid fractions and 25 liquid fractions after separation. The resulting typology outlined that fertilizing-values are linked to AD feedstock and process. As case study regulations, no digestate (without any post-treatment) fulfilled French standards and the latest European Union regulation proposal on fertilizers. Options to reach regulations' product categories were discussed according to the typology. For the first time, a digestate typology was established based on fertilizing value, which can be a useful tool enhancing digestate management and policy making.

Digestate mechanical separation: Efficiency profiles based on anaerobic digestion feedstock and equipment choice

Digestate mechanical separation is present in numerous anaerobic digestion plants. In this study, data from literature and from unpublished analysis were gathered to evaluate digestate separation efficiency for different mechanical separators. For the first time, efficiency indicators allowed the definition of two mass distribution profiles. The low-performance profile was characterized by each component being mainly destined to the liquid fraction, excluding P, Mg and Ca in a few cases. Screw presses represented 68% of these separators and 78% of digestates came from mainly fibrous inputs such as cow manure and silage. In the high-performance profile, digestate compounds were effectively concentrated in the solid fraction, except nitrogen. The great majority of separators were decanting centrifuges, and the anaerobic digestion inputs were principally non-fibrous such as pig slurry, sludge and agro-industrial waste. This study represents a source for benchmarking digestate separation and opens a possibility to forecast more realistically digestate separation performance.

Transcriptional subtyping and CD8 immunohistochemistry identifies poor prognosis stage II/III colorectal cancer patients who benefit from adjuvant chemotherapy

Purpose

Transcriptomic profiling of colorectal cancer (CRC) has led to the identification of four consensus molecular subtypes (CMS1 to 4) that have prognostic value in stage II and III disease. More recently, the Colorectal Cancer Intrinsic Subtypes (CRIS) classification system has helped to define the biology specific to the epithelial component of colorectal tumors; however, the clinical value of these classification systems in the prediction of response to standard-of-care adjuvant chemotherapy remains unknown.

Patients and Methods

Using samples from four European sites, we assembled a novel cohort of patients with stage II and III CRC (n = 156 samples) and performed transcriptomic profiling and targeted sequencing and generated a tissue microarray to enable integrated multiomics analyses. We also accessed data from two published cohorts of patients with stage II and III CRC: GSE39582 and GSE14333 (n = 479 and n = 185 samples, respectively).

Results

The epithelial-rich CMS2 subtype of CRC benefitted significantly from treatment with adjuvant chemotherapy in both stage II and III disease (P = .02 and P < .001, respectively), whereas the CMS3 subtype significantly benefitted in stage III only (P = .001). After CRIS substratification of CMS2, we observed that only the CRIS-C subtype significantly benefitted from treatment with adjuvant chemotherapy in stage II and III disease (P = .0081 and P < .001, respectively), whereas the CRIS-D subtype significantly benefitted in stage III only (P = .0034). We also observed that CRIS-C patients with low levels of CD8⁺ tumor-infiltrating lymphocytes were most at risk for relapse in both stage II and III disease (log-rank P = .0031; hazard ratio, 12.18 [95% CI, 1.51 to 98.58]).

Conclusion

Patient stratification using a combination of transcriptional subtyping and CD8 immunohistochemistry analyses is capable of identifying patients with poor prognostic stage II and III disease who benefit from adjuvant standard-of-care chemotherapy. These findings are particularly relevant for patients with stage II disease, where the overall benefit of adjuvant chemotherapy is marginal.

Characterization and prediction of organic nitrogen biodegradability during anaerobic digestion: A bioaccessibility approach

Prediction of organic nitrogen mineralization into ammonium during anaerobic digestion is required for optimizing substitution of mineral fertilizer by digestates. The aim of this study was to understand organic nitrogen biodegradability and to investigate how it can be predicted from carbon biodegradability, and nitrogen bioaccessibility, respectively. Bioaccessibility was assessed using fractionation methods based on sequential extractions. Results showed that organic nitrogen was present in fractions whose bioaccessibility levels differed. Organic nitrogen and carbon biodegradability were also determined and compared. Results highlighted two groups of substrates: the first with an initial NH₄⁺/TKN < 30%, whose carbon and nitrogen biodegradability are similar; the second with an initial NH₄⁺/TKN > 30%, whose carbon and nitrogen biodegradability differ significantly. To enable prediction on all substrates, partial least square (PLS) regressions were carried out to link organic nitrogen bioaccessibility indicators to biodegradability. The models successfully predicted organic nitrogen biodegradability with a maximum prediction error of 10%.

Barriers to the treatment of childhood tuberculous infection and tuberculosis disease: a qualitative study

SETTING

In 2012, Peru's National TB Program (NTP) reported approximately 2400 incident cases of tuberculosis (TB) disease in children aged <15 years. Peru's TB burden is concentrated in the Lima metropolitan area, particularly in poor districts such as El Agustino and La Victoria, where this study was conducted.

OBJECTIVE

To identify barriers to the treatment of childhood tuberculous infection and TB disease in Lima from the perspective of front-line providers and patients' families.

DESIGN

We conducted 10 semi-structured focus groups with 53 purposefully sampled primary care providers, community health workers, and parents/guardians of pediatric TB patients. We also completed nine in-depth interviews with National TB Program administrators and pulmonologists specializing in TB. Two authors performed inductive thematic analysis and identified emerging themes.

RESULTS

Four main treatment barriers emerged from the data: 1) dosing errors, 2) time- and labor-intensive preparation and administration of medications, 3) provider concern that isoniazid preventive therapy (IPT) generates isoniazid resistance, and 4) poor adherence to IPT.

CONCLUSION

Our findings highlight the urgent need for child-friendly formulations, provider and parent/guardian education about IPT, and strategies to promote adherence to IPT, including support and supervision by health workers and/or regimens with fewer doses.

The structural basis of alpha-tropomyosin linked (Asp230Asn) familial dilated cardiomyopathy

Recently, linkage analysis of two large unrelated multigenerational families identified a novel dilated cardiomyopathy (DCM)-linked mutation in the gene coding for alpha-tropomyosin (TPM1) resulting in the substitution of an aspartic acid for an asparagine (at residue 230). To determine how a single amino acid mutation in α-tropomyosin (Tm) can lead to a highly penetrant DCM we generated a novel transgenic mouse model carrying the D230N mutation. The resultant mouse model strongly phenocopied the early onset of cardiomyopathic remodeling observed in patients as significant systolic dysfunction was observed by 2months of age. To determine the precise cellular mechanism(s) leading to the observed cardiac pathology we examined the effect of the mutation on Ca²⁺ handling in isolated myocytes and myofilament activation in vitro. D230N-Tm filaments exhibited a reduced Ca²⁺ sensitivity of sliding velocity. This decrease in sensitivity was coupled to increase in the peak amplitude of Ca²⁺ transients. While significant, and consistent with other DCMs, these measurements are comprised of complex inputs and did not provide sufficient experimental resolution. We then assessed the primary structural effects of D230N-Tm. Measurements of the thermal unfolding of D230N-Tm vs WT-Tm revealed an increase in stability primarily affecting the C-terminus of the Tm coiled-coil. We conclude that the D230N-Tm mutation induces a decrease in flexibility of the C-terminus via propagation through the helical structure of the protein, thus decreasing the flexibility of the Tm overlap and impairing its ability to regulate contraction. Understanding this unique structural mechanism could provide novel targets for eventual therapeutic interventions in patients with Tm-linked cardiomyopathies.