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We present a systematic structural and energetic characterization of phosphate(OP)–nucleobase anion…π stacking interactions in RNAs. We observed OP–nucleobase stacking contacts in a variety of structural motifs other than regular helices and spanning broadly diverse sequence distances. Apart from the stacking between a phosphate and a guanine or a uracil two-residue upstream in specific U-turns, such interactions in RNA have been scarcely characterized to date. Our QM calculations showed an energy minimum at a distance between the OP atom and the nucleobase plane centroid slightly below 3 Å for all the nucleobases. By sliding the OP atom over the nucleobase plane we localized the optimal mutual positioning of the stacked moieties, corresponding to an energy minimum below -6 kcal•mol−1, for all the nucleobases, consistently with the projections of the OP atoms over the different π-rings we observed in experimental occurrences. We also found that the strength of the interaction clearly correlates with its electrostatic component, pointing to it as the most relevant contribution. Finally, as OP–uracil and OP–guanine interactions represent together 86% of the instances we detected, we also proved their stability under dynamic conditions in model systems simulated by state-of-the art DFT-MD calculations.

Background Transbronchial lung biopsy with radial endobronchial ultrasound (rEBUS-TBB) and Computed tomography (CT) scan guided transthoracic biopsy (CT-TTB) are commonly used to investigate peripheral lung nodules but high quality data is still not clear about the diagnostic and safety profile comparison of these two modalities. Method We included all randomized controlled trials (RCT) comparing rEBUS-TBB with a flexible bronchoscope and CT-TTB for solitary lung nodules. Two reviewers extracted data independently on diagnostic performance and complication rates. Results 170 studies were screened, 4 RCT with total of 325 patients were included. CT-TTB had a higher diagnostic yield than rEBUS-TBB (83.45% vs 68.82%, risk difference − 0.15, 95% CI, [-0.24,-0.05]), especially for lesion size 1–2 cm (83% vs 50%, risk difference − 0.33, 95% CI, [-0.51,-0.14]). For malignant diseases, rEBUS-TBB had a combined diagnostic yield of 75.75% vs 87.7% of CT-TTB. rEBUS-TBB had a significant better safety profile with lower risk of pneumothorax (2.87% vs 21.43%, OR = 0.12, 95% CI [0.05–0.32]) and combined outcomes of hospital admission, hemorrhage and pneumothorax (8.62% vs 31.81%, OR 0.21, 95% CI, [0.11–0.40]). Factors increasing diagnostic yield of rEBUS were lesion size and localization of the probe but not the distance to the chest wall, hilum nor probe localizing adjacent to the lesion. Conclusion CT-TTB has a higher diagnostic yield than rEBUS-TBB in diagnosing peripheral lung nodules, particularly for lesions from 1 cm to 2 cm. However, rEBUS-TBB is significantly safer with five to eight times less risk of pneumothorax and composite complications of hospital admission, hemorrhage and pneumothorax.

BACKGROUND: A percutaneous transthoracic needle biopsy (PTNB) is performed to obtain tissue for a pathologic diagnosis. A PTNB is necessary prior to the initiation of many cancer treatments. There is a risk of hemoptysis, the expectoration of blood, with the possibility for adverse, life-threatening outcomes. A critical event checklist is a cognitive aid used in an emergency to ensure critical steps are followed. To date, there are no known checklists published for management of PTNB-related, life-threatening hemoptysis. The purpose of this report is to describe the development and implementation of a critical event checklist and the adoption of the checklist into hemoptysis management. METHODS: In March 2017, a process improvement team convened to evaluate the hemoptysis response using the Plan-Do-Study-Act (PDSA) methodology. The checklist was evaluated and updated through September 2019. The team educated Interventional Radiology (IR) clinicians on the new checklist and conducted simulations on its use. A retrospective chart review was performed on hemoptysis events between the ten-year period of October 1, 2008 and September 30, 2018 to evaluate the adoption of the checklist into practice. RESULTS: There were 231 hemoptysis events occurring in 229 patients (2 with repeat biopsies). Prior to implementing the protocol and checklist, there were 166 (71.9%) hemoptysis events. After implementation there were 65 (28.1%) events. The median amount of documented blood expectorated with hemoptysis was 100 mL (IQR 20.0–300.0). Twenty-six patients were admitted after PTNB for reasons related to the hemoptysis event (11.3%). During the procedure, four (1.7%) patients with hemoptysis suffered a cardiac arrest. Prior to implementation of the protocol and critical events checklist, nurses positioned patients in the lateral decubitus (LD) position in 40 out of 162 (24.7%) cases. After implementation of the critical events checklist, nurses positioned patients in the LD position 42 out of 65 cases (64.6%) (OR=5.57(95% CI 2.99–10.367), p

Molecular diagnostic assays require samples with high nucleic acid content to generate reliable data. Similarly, programmed death-ligand 1 (PD-L1) immunohistochemistry (IHC) requires samples with adequate tumor content. We investigated whether shape-sensing robotic-assisted bronchoscopy (ssRAB) provides adequate samples for molecular and predictive testing.We retrospectively identified diagnostic samples from a prospectively collected database. Pathologic reports were reviewed to assess adequacy of samples for molecular testing and feasibility of PD-L1 IHC. Tumor cellularity was quantified by an independent pathologist using paraffin-embedded sections. Univariable and multivariable linear regression models were constructed to assess associations between lesion- and procedure-related variables and tumor cellularity.In total, 128 samples were analyzed: 104 primary lung cancers and 24 metastatic lesions. On initial pathologic assessment, ssRAB samples were deemed to be adequate for molecular testing in 84% of cases; on independent review of cellular blocks, median tumor cellularity was 60% (interquartile range, 25%-80%). Hybrid capture-based next-generation sequencing was successful for 25 of 26 samples (96%), polymerase chain reaction-based molecular testing (Idylla; Biocartis) was successful for 49 of 52 samples (94%), and PD-L1 IHC was successful for 61 of 67 samples (91%). Carcinoid and small cell carcinoma histologic subtype and adequacy on rapid on-site evaluation were associated with higher tumor cellularity.The ssRAB platform provided adequate tissue for next-generation sequencing, polymerase chain reaction-based molecular testing, and PD-L1 IHC in80% of cases. Tumor histology and adequacy on intraoperative cytologic assessment might be associated with sample quality and suitability for downstream assays.

Background: The impact of the coronavirus disease (COVID-19) pandemic extends beyond the realms of patient care and healthcare resource use to include medical education; however, the repercussions of COVID-19 on the quality of training and trainee perceptions have yet to be explored. Objective: The purpose of this study was to determine the degree of interventional pulmonology (IP) fellows’ involvement in the care of COVID-19 and its impact on fellows’ clinical education, procedure skills, and postgraduation employment search. Methods: An internet-based survey was validated and distributed among IP fellows in North American fellowship training programs. Results: Of 40 eligible fellows, 38 (95%) completed the survey. A majority of fellows (76%) reported involvement in the care of patients with COVID-19. Fellows training in the Northeast United States reported involvement in the care of a higher number of patients with COVID-19 than in other regions (median, 30 [interquartile range, 20–50] vs. 10 [5–13], respectively; P

To evaluate the efficacy of using bronchoscopically implanted anchored electromagnetic transponders (EMTs) as surrogates for 1) tumor position and 2) repeatability of lung inflation during deep-inspiration breath-hold (DIBH) lung radiotherapy.Forty-one patients treated with either hypofractionated (HF) or conventional (CF) lung radiotherapy on an IRB-approved prospective protocol using coached DIBH were evaluated for this study. Three anchored EMTs were bronchoscopically implanted into small airways near or within the tumor. DIBH treatment was gated by tracking the EMT positions. Breath-hold cone-beam-CTs (CBCTs) were acquired prior to every HF treatment or weekly for CF patients. Retrospectively, rigid registrations between each CBCT and the breath-hold planning CT were performed to match to 1) spine, 2) EMTs and 3) tumor. Absolute differences in registration between EMTs and spine were analyzed to determine surrogacy of EMTs for lung inflation. Differences in registration between EMTs and the tumor were analyzed to determine surrogacy of EMTs for tumor position. The stability of the EMTs was evaluated by analyzing the difference between inter-EMT displacements recorded at treatment from that of the plan for the CF patients, as well as the geometric residual (GR) recorded at the time of treatment.A total of 219 CBCTs were analyzed. The average differences between EMT centroid and spine registration among all CBCTs were 0.45±0.42 cm, 0.29±0.28 cm, and 0.18±0.15 cm in superior-inferior (SI), anterior-posterior (AP) and lateral directions, respectively. Only 59% of CBCTs had differences in registration 0.5 cm for EMT centroid compared to spine, indicating that lung inflation is not reproducible from simulation to treatment. The average differences between EMT centroid and tumor registration among all CBCTs were 0.13±0.13 cm, 0.14±0.13 cm and 0.12±0.12 cm in SI, AP and lateral directions, respectively. Ninety-five percent of CBCTs resulted in a 0.5 cm change between EMT centroid and tumor registration, indicating that EMT positions correspond well with tumor position during treatments. Six out of the seven recorded CF patients had average differences in inter-EMT displacements ≤0.26 cm and average GR ≤0.22 cm, indicating that the EMTs are stable throughout treatment.Bronchoscopically implanted anchored EMTs are good surrogates for tumor position and are reliable for maintaining tumor position when tracked during DIBH treatment, as long as the tumor size and shape are stable. Large differences in registration between EMTs and spine for many treatments suggest that lung inflation achieved at simulation is often not reproduced.

Purpose Multibeam intensity modulated radiation therapy (IMRT) enhances the therapeutic index by increasing the dosimetric coverage of the targeted tumor tissues while minimizing volumes of adjacent organs receiving high doses of RT. The tradeoff is that a greater volume of lung is exposed to low doses of RT, raising concern about the risk of radiation pneumonitis (RP). Methods and Materials Between July 2010 and January 2013, patients with node-positive breast cancer received inverse-planned, multibeam IMRT to the breast or chest wall and regional nodes, including the internal mammary nodes (IMNs). The primary endpoint was feasibility, predefined by dosimetric treatment planning criteria. Secondary endpoints included the incidence of RP grade 3 or greater and changes in pulmonary function measured with the Common Terminology Criteria for Adverse Events version 3.0 scales, pulmonary function tests and community-acquired pneumonia questionnaires, obtained at baseline and 6 months after IMRT. Clinical follow-up was every 6 months for up to 5 years. Results Median follow-up was 53.4 months (range, 0-82 months). Of 113 patients enrolled, 104 completed follow-up procedures. Coverage of the breast or chest wall and IMN was comprehensive (median 48.1 Gy and 48.9 Gy, respectively). The median volume of lung receiving a high dose (V20Gy) and a low dose (V5) was 29% and 100%, respectively. The overall rate of respiratory toxicities was 10.6% (11/104), including 1 grade 3 RP event (0.96%). No differences were found in pulmonary function test or community-acquired pneumonia scores after IMRT. The 5-year rates of locoregional recurrence-free, disease-free, and overall survival were 93.2%, 63.6%, and 80.3%, respectively. Conclusions Multibeam IMRT in patients with breast cancer receiving regional nodal irradiation was dosimetrically feasible, based on early treatment planning criteria. Despite the large volume of lung receiving low-dose RT, the incidence of grade 3 RP was remarkably low, justifying inverse-planned IMRT as a treatment modality for patients with high-risk breast cancer in whom conventional RT techniques prove inadequate.

Endobronchial ultrasound (EBUS) bronchoscopy is an established minimally-invasive modality for visualization, characterization, and guidance of sampling of paratracheal and parabronchial structures and tissues. In the intensive care unit (ICU), rapidly obtaining an accurate diagnosis is paramount to the management of critically ill patients. In some instances, diagnosing and confirming terminal illness in a critically ill patient provides needed closure for patients and their loved ones. Currently available data on feasibility, safety, and yield of EBUS bronchoscopy in critically ill patients is based on single center experiences. These data suggest that in select ICU patients convex and radial probe-EBUS bronchoscopy can serve as useful tools in the evaluation of mediastinal lymphadenopathy, central airway obstruction, pulmonary embolism, and peripheral lung lesions. Barriers to the use of EBUS bronchoscopy in the ICU include: (I) requirement for dedicated equipment, prolonged procedure time, and bronchoscopy team expertise that may not be available; (II) applicability to a limited number of patients and conditions in the ICU; and (III) technical difficulty related to the relatively large outer diameter of the convex probe-EBUS bronchoscope and an increased risk for adverse cardiopulmonary consequences due to intermittent obstruction of the artificial airway. While the prospects for EBUS bronchoscopy in critically ill patients appear promising, judicious patient selection in combination with bronchoscopy team expertise are of utmost importance when considering performance of EBUS bronchoscopy in the ICU setting.

Mammalian cell surfaces are modified with complex arrays of glycans that play major roles in health and disease. Abnormal glycosylation is a hallmark of cancer; terminal sialic acid and fucose in particular have high levels in tumor cells, with positive implications for malignancy. Increased sialylation and fucosylation are due to the upregulation of a set of sialyltransferases (STs) and fucosyltransferases (FUTs), which are potential drug targets in cancer. In the past, several advances in glycostructural biology have been made with the determination of crystal structures of several important STs and FUTs in mammals. Additionally, how the independent evolution of STs and FUTs occurred with a limited set of global folds and the diverse modular ability of catalytic domains toward substrates has been elucidated. This review highlights advances in the understanding of the structural architecture, substrate binding interactions, and catalysis of STs and FUTs in mammals. While this general understanding is emerging, use of this information to design inhibitors of STs and FUTs will be helpful in providing further insights into their role in the manifestation of cancer and developing targeted therapeutics in cancer.

BACKGROUND: The landscape of guided bronchoscopy for the sampling of pulmonary parenchymal lesions is evolving rapidly. Shape-sensing robotic-assisted bronchoscopy (ssRAB) recently was introduced as means to allow successful sampling of traditionally challenging lesions. RESEARCH QUESTION: What are the feasibility, diagnostic yield, determinants of diagnostic sampling, and safety of ssRAB in patients with pulmonary lesions? STUDY DESIGN AND METHODS: Data from 131 consecutive ssRAB procedures performed at a US-based cancer center between October 2019 and July 2020 were captured prospectively and analyzed retrospectively. Definitions of diagnostic procedures were based on prior standards. Associations of procedure- and lesion-related factors with diagnostic yield were examined by univariate and multivariate generalized linear mixed models. RESULTS: A total of 159 pulmonary lesions were targeted during 131 ssRAB procedures. The median lesion size was 1.8 cm, 59.1% of lesions were in the upper lobe, and 66.7% of lesions were beyond a sixth-generation airway. The navigational success rate was 98.7%. The overall diagnostic yield was 81.7%. Lesion size of ≥ 1.8 cm and central location were associated significantly with a diagnostic procedure in the univariate analysis. In the multivariate model, lesions of ≥ 1.8 cm were more likely to be diagnostic compared with lesions < 1.8 cm, after adjusting for lung centrality (OR, 12.22; 95% CI, 1.66-90.10). The sensitivity and negative predictive value of ssRAB for primary thoracic malignancies were 79.8% and 72.4%, respectively. The overall complication rate was 3.0%, and the pneumothorax rate was 1.5%. INTERPRETATION: This study was the first to provide comprehensive evidence regarding the usefulness and diagnostic yield of ssRAB in the sampling of pulmonary parenchymal lesions. ssRAB may represent a significant advancement in the ability to access and sample successfully traditionally challenging pulmonary lesions via the bronchoscopic approach, while maintaining a superb safety profile. Lesion size seems to remain the major predictor of a diagnostic procedure.

BackgroundPneumonitis related to immune checkpoint blockade is uncommon but can be severe, fatal or chronic. Steroids are first-line treatment, however, some patients are refractory or become resistant to steroids. Like many immune-related adverse events, little is known regarding the outcomes and optimal management of patients in whom steroids are ineffective.MethodsWe performed a single-center retrospective cohort study at a high-volume tertiary cancer center to evaluate the clinical course, management strategies and outcomes of patients treated for immune checkpoint pneumonitis with immune modulatory medications in addition to systemic steroids. Pharmacy records were queried for patients treated with both immune checkpoint blockade and receipt of additional immune modulators. Records were then manually reviewed to identify patients who received the additional immune modulators for immune checkpoint pneumonitis.ResultsFrom 2013 to 2020, we identified 26 patients treated for immune checkpoint pneumonitis with additional immune modulators in addition to steroids. Twelve patients (46%) were steroid-refractory and 14 (54%) were steroid-resistant. Pneumonitis severity included grade 2 (42%) or grade 3–4 (58%). Additional immune modulation consisted of tumor necrosis factor-alpha inhibitor (77%) and/or mycophenolate (23%). Durable improvement in pneumonitis following initiation of additional immune modulators occurred in 10 patients (38%), including three patients (12%) in whom pneumonitis resolved and all immunosuppressants ceased. The rate of 90-day all-cause mortality/hospice referral was 50%. At last follow-up, mortality attributable to pneumonitis was 23%. In addition to mortality from pneumonitis and cancer, 3 patients (12%) died due to infections possibly associated with immunosuppression.ConclusionsSteroid-refractory or -resistant immune checkpoint pneumonitis is uncommon but associated with significant morbidity and mortality. Additional immunomodulators can yield durable improvement, attained in over one third of patients. An improved understanding of the underlying biology of immune-related pneumonitis will be crucial to guide more precise and effective treatment strategies in the future.

International audience; The expansion of the genetic alphabet with additional, unnatural base pairs (UBPs) is an important and long-standing goal in synthetic biology. Nucleotides acting as ligands for the coordination of metal cations have advanced as promising candidates for such an expansion of the genetic alphabet. However, the inclusion of artificial metal base pairs in nucleic acids mainly relies on solid-phase synthesis approaches, and very little is known about polymerase-mediated synthesis. Herein, we report the selective and high yielding enzymatic construction of a silver-mediated base pair (dImC–AgI–dPurP) as well as a two-step protocol for the synthesis of DNA duplexes containing such an artificial metal base pair. Guided by DFT calculations, we also shed light into the mechanism of formation of this artificial base pair as well as into the structural and energetic preferences. The enzymatic synthesis of the dImC–AgI–dPurP artificial metal base pair provides valuable insights for the design of future, more potent systems aiming at expanding the genetic alphabet.

We employ density functional theory (DFT) and time-dependent DFT (TDDFT) calculations to investigate the structural, energetic and optical properties of a new computationally designed RNA alphabet, where the nucleobases, tsA, tsG, tsC, and tsU (ts-bases), have been derived by replacing sulfur with selenium in the previously reported tz-bases, based on the isothiazolo[4,3-d]pyrimidine heterocycle core. We find out that the modeled non-natural bases have minimal impact on the geometry and energetics of the classical Watson-Crick base pairs, thus potentially mimicking the natural bases in a RNA duplex in terms of H-bonding. In contrast, our calculations indicate that H-bonded base pairs involving the Hoogsteen edge of purines are destabilized as compared to their natural counterparts. We also focus on the photophysical properties of the non-natural bases and correlate their absorption/emission peaks to the strong impact of the modification on the energy of the lowest unoccupied molecular orbital. It is indeed stabilized by roughly 1.1-1.6 eV as compared to the natural analogues, resulting in a reduction of the gap between the highest occupied and the lowest unoccupied molecular orbital from 5.3-5.5 eV in the natural bases to 3.9-4.2 eV in the modified ones, with a consequent bathochromic shift in the absorption and emission spectra. Overall, our analysis clearly indicates that the newly modelled ts-bases are expected to exhibit better fluorescent properties as compared to the previously reported tz-bases, while retaining similar H-bonding properties. In addition, we show that a new RNA alphabet based on size-extended benzo-homologated ts-bases can also form stable Watson-Crick base pairs with the natural complementary nucleobases.

Although, 3,5,6-Trichlorosalicylic acid (TCSA) does not show good antibacterial activity, but its metal complexes have shown better activity for the selected bacterial strains with good degree of selectivity. Amongst the eight synthesized essential metal complexes of TCSA, Mn(II)-TCSA and Ni(II)-TCSA have been found to be more effective with MIC range of 20–50 µg/L as compared to control (chloramphenicol). The activity of an individual complex against different microbes was not identical, indicating the usage of an individual metal chelate against a targeted bacterial strain. Besides, the protein (BSA) binding constant of TCSA and its metal complexes were determined and ordered as Ca(II)-TCSA > Cu(II)-TCSA > Mg(II)-TCSA ≫ Mn(II)-TCSA ≫ Zn(II)-TCSA >>> Ni(II)-TCSA >>> Co(II)-TCSA > Fe(II)-TCSA > TCSA. The present study has confirmed enhanced antibacterial activity and binding constants for the metal chelates of TCSA in comparison to free TCSA, which seems directly related with the antioxidant activity of these complexes. Further, bearing the ambiguity related to the structural characterization of the metal complexed with TCSA ligand, DFT calculations have been employed as the tool to unravel the right environment around the metals, studying basically the relative stability of square planar and octahedral metal complexes of TCSA.

Dyes are major water pollutants due to their large-scale industrial applications. Dyes adversely impact both aquatic and human health. Thus, they require efficient removal from water bodies. Adsorption is an effective method for removing dyes from polluted water. In this study, we simulated the adsorption of bromophenol blue, methylene blue, and methyl orange by asphaltene and its functionalized version. Adsorption was simulated using molecular dynamics (MD) and density functional theory (DFT) calculations. Our results indicated that functionalized and nonfunctionalized dyes have varying interaction energies depending on the nature of the dye. MD simulations indicated that methylene blue tends to have a stronger interaction with asphaltene than the other dyes. Methyl orange bound more strongly with the functionalized asphaltene (FASP) than with the other dyes. Bromophenol blue dye demonstrated weak interaction with both types of asphaltene. DFT calculations were conducted to understand the nature and strength of the interactions between the dyes and asphaltene. In this study, we also analyzed binding energy, electrostatic potential, frontier molecular orbitals, and noncovalent interactions. The DFT and MD analyses supported the experimental finding that FASP is a better adsorbent of dyes than nonfunctionalized asphaltene.

Background Parallel development of preclinical models that recapitulate treatment response observed in patients is central to the advancement of personalized medicine. Objective To evaluate the use of biopsy specimens to develop patient-derived xenografts and the use of corresponding cell lines from renal cell carcinoma (RCC) tumors for the assessment of histopathology, genomics, and treatment response. Design, setting, and participants A total of 74 tumor specimens from 66 patients with RCC were implanted into immunocompromised NOD- SCID IL2Rg −/− mice. Four cell lines generated from patients' specimens with clear cell pathology were used for comparative studies. Outcome measurements and statistical analysis Preclinical models were established and assessed. Engraftment rates were analyzed using chi-square testing. Analysis of variance (two-way analysis of variance) was conducted to assess tumor growth. Results and limitations Overall, 33 RCC mouse xenograft models were generated with an overall engraftment rate of 45% (33 of 74). Tumor biopsies engrafted comparably with surgically resected tumors (58% vs 41%; p =0.3). Xenograft tumors and their original tumors showed high fidelity in regard to histology, mutation status, copy number change, and targeted therapy response. Engraftment rates from metastatic tumors were higher but not more significant than primary tumors (54% vs 34%; p =0.091). Our engraftment rate using metastases or biopsies was comparable with recent reports using resected primary tumors. In stark contrast to corresponding cell lines, all tested xenografts recapitulated patients' clinical response to sunitinib. Conclusions Patient-derived xenograft models can be effectively established from tumor biopsies. Preclinical xenograft models but not matched cell lines reflected clinical responses to sunitinib. Patient summary Matched patient-derived clear cell renal cell carcinoma xenografts and cell lines from responsive and refractory patients treated with sunitinib were established and evaluated for pharmacologic response to anti–vascular endothelial growth factor treatment. Both models accurately reflected the genetic characteristics of original tumors, but only xenografts recapitulated drug responses observed in patients. These models could serve as a powerful platform for precision medicine.

While web applications continue to employ traditional client-server model, most of the current applications demand real time bi-directional communication. In such setups, data exchanges between both the parties (client and server) are very frequent. Thus, performance of the network is subject to various factors decided by the choice of data exchange mechanism. This shows that the choice of data exchange mechanism is vital to performance of a web-application employing it. This paper compares various data exchange mechanisms with respect to factors affecting real time web applications. While the absolute values of benchmarking may vary with the systems, the relative difference between them can be used as a reference for selecting a mechanism for an application. Hence, this paper can be used as a reference to choose appropriate data exchange mechanism for the concerned application.

Layered double hydroxides (LDHs) of Mn with Co were successfully synthesized via polyol reduction method. Morphology and particle size of the LDHs were thoroughly characterized using advanced techniques such as transmission electron microscopy, field emission scanning electron microscopy and atomic force microscopy. The elemental composition of the composites was studied with energy dispersive X-ray analysis and X-ray photoelectron spectroscopy. Morphology of the LDHs varied from small irregular particles to larger aggregates with increasing the reaction temperatures viz. 50, 70, 110, 150 and 200 °C. The meso-ordering, crystallinity and chemical composition also varied with change in reaction temperature. The LDHs enhanced the burning rates of composite solid propellants to many folds. Simultaneous thermo gravimetric analysis – differential scanning calorimetry revealed that the burning rate enhancement by the LDHs was due to their exceptional catalytic activity in the thermal decomposition of ammonium perchlorate. The LDH that was synthesized at 110 °C was found to be the best catalyst among all.