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MXenes are known for their exceptional electrical conductivity and surface functionality, gaining interest as promising anode materials for Li-ion batteries. However, conventional 2D multilayered MXenes often exhibit limited electrochemical applicability due to slow ion transport kinetics and low structural stability. Addressing these challenges, this study develops a 3D flower-type double transition metal MXene, Mo 2 Ti 2 C 3 Cl x , with precisely engineered in-plane mesoporosity using HF-free Lewis acid-assisted molten salt method, coupled with intercalation and freeze-drying. The molar ratio of Lewis acid to eutectic salts is meticulously controlled to create the mesoporosity, which is preserved through freeze-drying. Molecular dynamics (MD) simulations assess the impact of in-plane pore size on the structure and transport dynamics of electrolyte components. Density functional theory (DFT) shows that chlorine surface functional groups significantly reduce Li-ion diffusion barriers, thereby enhancing ion transport and battery performance. Electrochemical evaluations reveal that small-sized (2-5 nm) mesoporous Mo 2 Ti 2 C 3 Cl x achieves a specific capacity of 324 mAh g -1 at 0.2 A g -1 and maintains 97% capacity after 500 cycles at 0.5 A g -1 , outperforming larger-pored (10 nm) and non-porous variants. This research highlights a scalable strategy for designing mesoporous materials that optimize ion transport and structural stability, essential for advancing next-generation high-performance energy storage solutions., (© 2024 The Author(s). Small published by Wiley‐VCH GmbH.)

Tacrolimus metabolism is heavily influenced by the CYP3A5 genotype, which varies widely among African Americans (AA). We aimed to assess the performance of a published genotype-informed tacrolimus dosing model in an independent set of adult AA kidney transplant (KTx) recipients. CYP3A5 genotypes were obtained for all AA KTx recipients (n = 232) from 2010 to 2019 who met inclusion criteria at a single transplant center in Philadelphia, Pennsylvania, USA. Medical record data were used to calculate predicted tacrolimus clearance using the published AA KTx dosing equation and two modified iterations. Observed and model-predicted trough levels were compared at 3 days, 3 months, and 6 months post-transplant. The mean prediction error at day 3 post-transplant was 3.05 ng/mL, indicating that the model tended to overpredict the tacrolimus trough. This bias improved over time to 1.36 and 0.78 ng/mL at 3 and 6 months post-transplant, respectively. Mean absolute prediction error-a marker of model precision-improved with time to 2.33 ng/mL at 6 months. Limiting genotype data in the model decreased bias and improved precision. The bias and precision of the published model improved over time and were comparable to studies in previous cohorts. The overprediction observed by the published model may represent overfitting to the initial cohort, possibly limiting generalizability., (© 2024 The Authors. The Journal of Clinical Pharmacology published by Wiley Periodicals LLC on behalf of American College of Clinical Pharmacology.)

In a previous study, heart xenografts from 10-gene-edited pigs transplanted into two human decedents did not show evidence of acute-onset cellular- or antibody-mediated rejection. Here, to better understand the detailed molecular landscape following xenotransplantation, we carried out bulk and single-cell transcriptomics, lipidomics, proteomics and metabolomics on blood samples obtained from the transplanted decedents every 6 h, as well as histological and transcriptomic tissue profiling. We observed substantial early immune responses in peripheral blood mononuclear cells and xenograft tissue obtained from decedent 1 (male), associated with downstream T cell and natural killer cell activity. Longitudinal analyses indicated the presence of ischemia reperfusion injury, exacerbated by inadequate immunosuppression of T cells, consistent with previous findings of perioperative cardiac xenograft dysfunction in pig-to-nonhuman primate studies. Moreover, at 42 h after transplantation, substantial alterations in cellular metabolism and liver-damage pathways occurred, correlating with profound organ-wide physiological dysfunction. By contrast, relatively minor changes in RNA, protein, lipid and metabolism profiles were observed in decedent 2 (female) as compared to decedent 1. Overall, these multi-omics analyses delineate distinct responses to cardiac xenotransplantation in the two human decedents and reveal new insights into early molecular and immune responses after xenotransplantation. These findings may aid in the development of targeted therapeutic approaches to limit ischemia reperfusion injury-related phenotypes and improve outcomes., (© 2024. The Author(s), under exclusive licence to Springer Nature America, Inc.)

Background: Oral microbiome sequencing has revealed key links between microbiome dysfunction and dental caries. However, these efforts have largely focused on Western populations, with few studies on the Middle Eastern communities. The current study aimed to identify the composition and abundance of the oral microbiota in saliva samples of children with different caries levels using machine learning approaches., Methods: Oral microbiota composition and abundance were identified in 250 Saudi participants with high dental caries and 150 with low dental caries using 16 S rRNA sequencing on a NextSeq 2000 SP flow cell (Illumina, CA) using 250 bp paired-end reads, and attempted to build a classifier using random forest models to assist in the early detection of caries., Results: The ADONIS test results indicate that there was no significant association between sex and Bray-Curtis dissimilarity (p ~ 0.93), but there was a significant association with dental caries status (p ~ 0.001). Using an alpha level of 0.05, five differentially abundant operational taxonomic units (OTUs) were identified between males and females as the main effect along with four differentially abundant OTUs between high and low dental caries. The mean metrics for the optimal hyperparameter combination using the model with only differentially abundant OTUs were: Accuracy (0.701); Matthew's correlation coefficient (0.0509); AUC (0.517) and F1 score (0.821) while the mean metrics for random forest model using all OTUs were:0.675; 0.054; 0.611 and 0.796 respectively., Conclusion: The assessment of oral microbiota samples in a representative Saudi Arabian population for high and low metrics of dental caries yields signatures of abundances and diversity., (© 2023. The Author(s).)

The Ni-rich layered oxide cathode has shown high energy density, proper rate capability, and longevity of the rechargeable battery, while poor stability and capacity fading are assumed to be its common cons. To address this obstacle, prospective cathode materials are synthesized by integrating the lithium transition metal oxides with an artificial cathode electrolyte interphase (CEI) layer. Herein, plasma-enhanced atomic layer deposition (PEALD) is employed to coat the LiNi 0.8 Mn 0.1 Co 0.1 O 2 (NMC811) electrode with Al 2 O 3 and MoO 3 . The combined results from morphological examinations revealed the formation of uniform Al 2 O 3 and MoO 3 sheets after 200 cycles of PEALD coating. Consistent results from the XRD analysis demonstrate that Al 2 O 3 and MoO 3 artificial CEIs can reduce Li-Ni mixing. The cyclic voltammetry tests show the oxidation-reduction kinetic. The modified NMC811 structures with Al 2 O 3 and MoO 3 represent a remarkable improvement in terms of capacity retention. The coated cathode with Al 2 O 3 clearly outperforms the modified configuration with MoO 3 concerning ionic conductivity, charge/discharge reversibility, and capacity retention. The promising results obtained in this study open the possibility of synthesizing Ni-rich cathodes with enhanced electrochemical performance.

The drastic volume expansion and dendrite growth of lithium metal anodes give rise to poor electrochemical reversibility. Herein, ZnO, N dually doped nanocages (c-ZNCC) were synthesized as the host for lithium metal anodes using the zeolitic imidazolate framework-8 (ZIF-8). The synthesis is based on a two-step core@shell evolution mechanism, which could guide lithium deposition rapidly and offer a fast lithium-ion diffusion during the cycling process. Benefiting from the unique design, the as-obtained c-ZNCC can render a record short lithium infusion as low as 1.5 s, a stable lithium stripping/plating capability as long as 3000 h, and a voltage hysteresis of 95 mV when cycling at 10 mA cm -2 to 10 mA h cm -2 . A low Tafel slope of 3.45 mA cm -2 demonstrates the efficient charge transfer of c-ZNCC-Li, and the galvanostatic intermittent titration technique measurement shows high diffusion coefficient of c-ZNCC-Li during the charging process. In addition, the LNMO||c-ZNCC-Li cell exhibits a capacity retention as high as 93.7% at 1 C after 200 cycles. This work creates a new design for deriving nanocages with dual lithiophilic spots using a metal-organic framework and carbon cloth for favorable Li metal anodes.

Background: Crohn's diseases and ulcerative colitis, both of which are chronic immune-mediated disorders of the gastrointestinal tract are major contributors to the overarching Inflammatory bowel diseases. It has become increasingly evident that the pathological processes of IBDs results from interactions between genetic and environmental factors, which can skew immune responses against normal intestinal flora., Methods: The aim of this study is to assess and analyze the taxa diversity and relative abundances in CD and UC in the Saudi population. We utilized a sequencing strategy that targets all variable regions in the 16 S rRNA gene using the Swift Amplicon 16 S rRNA Panel on Illumina NovaSeq 6000., Results: The composition of stool 16 S rRNA was analyzed from 219 patients with inflammatory bowel disease and from 124 healthy controls. We quantified the abundance of microbial communities to examine any significant differences between subpopulations of samples. At the genus level, two genera in particular, Veillonella and Lachnoclostridium showed significant association with CD versus controls. There were significant differences between subjects with CD versus UC, with the top differential genera spanning Akkermansia, Harryflintia, Maegamonas and Phascolarctobacterium. Furthermore, statistically significant taxa diversity in microbiome composition was observed within the UC and CD groups., Conclusions: In conclusion we have shown that there are significant differences in gut microbiota between UC, CD and controls in a Saudi Arabian inflammatory bowel disease cohort. This reinforces the need for further studies in large populations that are ethnically and geographically diverse. In addition, our results show the potential to develop classifiers that may have add additional richness of context to clinical diagnosis of UC and CD with larger inflammatory bowel disease cohorts., (© 2023. The Author(s).)

Ischemic stroke represents a significant societal burden across the globe. Rare high penetrant monogenic variants and less pathogenic common single nucleotide polymorphisms (SNPs) have been described as being associated with risk of diseases. Genetic studies in Saudi Arabian patients offer a greater opportunity to detect rare high penetrant mutations enriched in these consanguineous populations. We performed whole exome sequencing on 387 ischemic stroke subjects from Saudi Arabian hospital networks with up to 20,230 controls from the Saudi Human Genome Project and performed gene burden analyses of variants in 177 a priori loci derived from knowledge-driven curation of monogenic and genome-wide association studies of stroke. Using gene-burden analyses, we observed significant associations in numerous loci under autosomal dominant and/or recessive modelling. Stroke subjects with modified Rankin Scale (mRSs) above 3 were found to carry greater cumulative polygenic risk score (PRS) from rare variants in stroke genes (standardized PRS mean > 0) compared to the population average (standardized PRS mean = 0). However, patients with mRS of 3 or lower had lower cumulative genetic risk from rare variants in stroke genes (OR (95%CI) = 1.79 (1.29-2.49), p = 0.0005), with the means of standardized PRS at or lower than 0. In conclusion, gene burden testing in Saudi stroke populations reveals a number of statistically significant signals under different disease inheritance models. However, interestingly, stroke subjects with mRS of 3 or lower had lower cumulative genetic risk from rare variants in stroke genes and therefore, determining the potential mRS cutoffs to use for clinical significance may allow risk stratification of this population., (© 2023. The Author(s).)

Background: Epilepsy, a serious chronic neurological condition effecting up to 100 million people globally, has clear genetic underpinnings including common and rare variants. In Saudi Arabia, the prevalence of epilepsy is high and caused mainly by perinatal and genetic factors. No whole-exome sequencing (WES) studies have been performed to date in Saudi Arabian epilepsy cohorts. This offers a unique opportunity for the discovery of rare genetic variants impacting this disease as there is a high rate of consanguinity among large tribal pedigrees., Results: We performed WES on 144 individuals diagnosed with epilepsy, to interrogate known epilepsy-related genes for known and functional novel variants. We also used an American College of Medical Genetics (ACMG) guideline-based variant prioritization approach in an attempt to discover putative causative variants. We identified 32 potentially causative pathogenic variants across 30 different genes in 44/144 (30%) of these Saudi epilepsy individuals. We also identified 232 variants of unknown significance (VUS) across 101 different genes in 133/144 (92%) subjects. Strong enrichment of variants of likely pathogenicity was observed in previously described epilepsy-associated loci, and a number of putative pathogenic variants in novel loci are also observed., Conclusion: Several putative pathogenic variants in known epilepsy-related loci were identified for the first time in our population, in addition to several potential new loci which may be prioritized for further investigation., (© 2022. The Author(s).)

Background: Heart transplantation provides a significant improvement in survival and quality of life for patients with end-stage heart disease, however many recipients experience different levels of graft rejection that can be associated with significant morbidities and mortality. Current clinical standard-of-care for the evaluation of heart transplant acute rejection (AR) consists of routine endomyocardial biopsy (EMB) followed by visual assessment by histopathology for immune infiltration and cardiomyocyte damage. We assessed whether the sensitivity and/or specificity of this process could be improved upon by adding RNA sequencing (RNA-seq) of EMBs coupled with histopathological interpretation., Methods: Up to 6 standard-of-care, or for-cause EMBs, were collected from 26 heart transplant recipients from the prospective observational Clinical Trials of Transplantation (CTOT)-03 study, during the first 12-months post-transplant and subjected to RNA-seq (n = 125 EMBs total). Differential expression and random-forest-based machine learning were applied to develop signatures for classification and prognostication., Results: Leveraging the unique longitudinal nature of this study, we show that transcriptional hallmarks for significant rejection events occur months before the actual event and are not visible using traditional histopathology. Using this information, we identified a prognostic signature for 0R/1R biopsies that with 90% accuracy can predict whether the next biopsy will be 2R/3R., Conclusions: RNA-seq-based molecular characterization of EMBs shows significant promise for the early detection of cardiac allograft rejection., (Copyright © 2022 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.)

MXenes show outstanding specific capacitance in aqueous electrolytes. However, the narrow potential window of aqueous electrolytes restrains the energy density. Ionic liquid electrolytes can provide a higher potential window and superior specific energy but are subject to slow ion transport and difficult intercalation for their larger ion size. It is desirable to explore larger interlayer-spaced ( d -spaced) MXenes that can facilitate the large ion intercalation-deintercalation process. This work reports the first-ever supercapacitor application of the Mo 2 Ti 2 C 3 MXene free-standing film electrode (f-Mo 2 Ti 2 C 3 ) using 1 M 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)-imide (EMIMTFSI) in acetonitrile electrolyte. Without any preintercalating agents, the authors achieved an interlayer spacing of ∼2.4 nm in the f-Mo 2 Ti 2 C 3 material through etching, followed by a vacuum-assisted filtration technique. The microstructure, electrochemical properties, and charge storage kinetics of the f-Mo 2 Ti 2 C 3 outperform the conventional f-Ti 3 C 2 T x . The f-Mo 2 Ti 2 C 3 -based symmetric two-electrode device exhibited remarkable specific energy and specific power of 188 Wh kg -1 and 22 kW kg -1 , respectively, along with a high specific capacitance of 152 F g -1 . This larger d -spaced f-Mo 2 Ti 2 C 3 can emerge as a better alternative to the conventional f-Ti 3 C 2 T x in ionic liquid electrolytes to design next-generation high-performance MXene supercapacitors., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

We report here on a hollow-fiber hierarchical porous carbon exhibiting an ultra-high specific surface area, synthesized by a facile method of carbonization and activation, using the Metaplexis Japonica (MJ) shell. The Metaplexis Japonica-based activated carbon demonstrated a very high specific surface area of 3635 m 2 g -1 . Correspondingly, the derived carbonaceous material delivers an ultra-high capacitance and superb cycle life in an alkaline electrolyte. The pore-ion size compatibility is optimized using tailored hierarchical porous carbon and different ion sized organic electrolytes. In ionic liquids nonaqueous based electrolytes we tailored the MJ carbon pore structure to the electrolyte ion size. The corresponding supercapacitor shows a superior rate performance and low impedance, and the device records specific energy and specific power densities as high as 76 Wh kg -1 and 6521 W kg -1 , as well as a pronounced cycling durability in the ionic liquid electrolytes. Overall, we suggest a protocol for promising carbonaceous electrode materials enabling superior supercapacitors performance.

Fabricating electrical double-layer capacitors (EDLCs) with high energy density for various applications has been of great interest in recent years. However, activated carbon (AC) electrodes are restricted to a lower operating voltage because they suffer from instability above a threshold potential window. Thus, they are limited in their energy storage. The deposition of inorganic compounds' atomic layer deposition (ALD) aiming to enhance cycling performance of supercapacitors and battery electrodes can be applied to the AC electrode materials. Here, we report on the investigation of zinc oxide (ZnO) coating strategy in terms of different pulse times of precursors, ALD cycles, and deposition temperatures to ensure high electrical conductivity and capacitance retention without blocking the micropores of the AC electrode. Crystalline ZnO phase with its optimal forming condition is obtained preferably using a longer precursor pulse time. Supercapacitors comprising AC electrodes coated with 20 cycles of ALD ZnO at 70 °C and operated in TEABF 4 /acetonitrile organic electrolyte show a specific capacitance of 23.13 F g -1 at 5 mA cm -2 and enhanced capacitance retention at 3.2 V, which well exceeds the normal working voltage of a commercial EDLC product (2.7 V). This work delivers an additional feasible approach of using ZnO ALD modification of AC materials, enhancing and promoting stable EDLC cells under high working voltages.

Background and Objectives: Next generation sequencing (NGS) has promising applications in transfusion medicine. Exome sequencing (ES) is increasingly used in the clinical setting, and blood group interpretation is an additional value that could be extracted from existing data sets. We provide the first release of an open-source software tailored for this purpose and describe its validation with three blood group systems., Materials and Methods: The DTM-Tools algorithm was designed and used to analyse 1018 ES NGS files from the ClinSeq ® cohort. Predictions were correlated with serology for 5 antigens in a subset of 108 blood samples. Discrepancies were investigated with alternative phenotyping and genotyping methods, including a long-read NGS platform., Results: Of 116 genomic variants queried, those corresponding to 18 known KEL, FY and JK alleles were identified in this cohort. 596 additional exonic variants were identified KEL, ACKR1 and SLC14A1, including 58 predicted frameshifts. Software predictions were validated by serology in 108 participants; one case in the FY blood group and three cases in the JK blood group were discrepant. Investigation revealed that these discrepancies resulted from (1) clerical error, (2) serologic failure to detect weak antigenic expression and (3) a frameshift variant absent in blood group databases., Conclusion: DTM-Tools can be employed for rapid Kell, Duffy and Kidd blood group antigen prediction from existing ES data sets; for discrepancies detected in the validation data set, software predictions proved accurate. DTM-Tools is open-source and in continuous development., (© 2020 International Society of Blood Transfusion.)

Designing high voltage (>3 V) and stable electrochemical supercapacitors with low self-discharge is desirable for the applications in modern electronic devices. This work demonstrates a 4 V symmetric supercapacitor with stabilized cycling performance through atomic layer deposition (ALD) of alumina (Al 2 O 3 ) on the surface of activated carbon (AC). The 20-cycle ALD Al 2 O 3 coated AC delivers 84 % capacitance retention after 1000 charge/discharge cycles under 4 V, contrary to the bare AC cells having only 48 % retention. The extended cycling life is associated with the thickened Stern layer and suppressed oxygen functional group. The self-discharge data also show that the Al 2 O 3 coating enables AC cells to maintain 53 % of charge retention after 12 h, which is more than twice higher than that of bare AC cells under the same test protocol of 4 V charging. The curve fitting analysis reveals that ALD coating induced slow self-discharge dominated by ion diffusion mechanism, thus enhancing the AC surface energy., (© 2021 The Authors. Published by Wiley-VCH GmbH.)

Designing the mesopore-dominated activated carbon electrodes has witnessed a significant breakthrough in enhancing the electrolyte breakdown voltage and energy density of supercapacitors. Herein, we designed N-doped mesoporous-dominated hierarchical activated carbon (N-dfAC) from the dragon fruit peel, an abundant biomass precursor, under the synergetic effect of KOH as the activating agent and melamine as the dopant. The electrode with the optimum N-doping content (3.4 at. %) exhibits the highest specific capacitance of 427 F g -1 at 5 mA cm -2 and cyclic stability of 123% capacitance retention until 50000 charge-discharge cycles at 500 mA cm -2 in aqueous 6 M KOH electrolytes. We designed a 4 V symmetric coin cell supercapacitor cell, which exhibits a remarkable specific energy and specific power of 112 W h kg -1 and 3214 W kg -1 , respectively, in organic electrolytes. The cell also exhibits a significantly higher cycle life (109% capacitance retention) after 5000 GCD cycles at the working voltage of ≥3.5 V than commercial YP-50 AC (∼60% capacitance retention). The larger Debye length of the diffuse ion layer permitted by the mesopores can explain the higher voltage window, and the polar N-doped species in the dfAC enhance capacitance and ion transport. The results endow a new path to design high-capacity and high-working voltage EDLCs from eco-friendly and sustainable biomass materials by properly tuning their pore structures., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

Background: Ductal adenocarcinoma of the prostate is an aggressive subtype, with high rates of biochemical recurrence and overall poor prognosis. It is frequently found coincident with conventional acinar adenocarcinoma. The genomic features driving evolution to its ductal histology and the biology associated with its poor prognosis remain unknown., Objective: To characterize genomic features distinguishing ductal adenocarcinoma from coincident acinar adenocarcinoma foci from the same patient., Design, Setting, and Participants: Ten patients with coincident acinar and ductal prostate cancer underwent prostatectomy. Laser microdissection was used to separately isolate acinar and ductal foci. DNA and RNA were extracted, and used for integrative genomic and transcriptomic analyses., Outcome Measurements and Statistical Analysis: Single nucleotide mutations, small indels, copy number estimates, and expression profiles were identified. Phylogenetic relationships between coincident foci were determined, and characteristics distinguishing ductal from acinar foci were identified., Results and Limitations: Exome sequencing, copy number estimates, and fusion genes demonstrated coincident ductal and acinar adenocarcinoma diverged from a common progenitor, yet they harbored distinct alterations unique to each focus. AR expression and activity were similar in both histologies. Nine of 10 cases had mutually exclusive CTNNB1 hotspot mutations or phosphatase and tensin homolog (PTEN) alterations in the ductal component, and these were absent in the acinar foci. These alterations were associated with changes in expression in WNT- and PI3K-pathway genes., Conclusions: Coincident ductal and acinar histologies typically are clonally related and thus arise from the same cell of origin. Ductal foci are enriched for cases with either a CTNNB1 hotspot mutation or a PTEN alteration, and are associated with WNT- or PI3K-pathway activation. These alterations are mutually exclusive and may represent distinct subtypes., Patient Summary: The aggressive subtype ductal adenocarcinoma is closely related to conventional acinar prostate cancer. Ductal foci contain additional alterations, however, leading to frequent activation of two targetable pathways., (Published by Elsevier B.V.)

The crystal structures of two closely related compounds, 1-cyclo-hexyl-2-(2-nitro-phen-yl)-1,3-thia-zolidin-4-one, C 15 H 18 N 2 O 3 S, (1) and 1-cyclo-hexyl-2-(2-nitro-phen-yl)-1,3-thia-zolidin-4-one 1,1-dioxide, C 15 H 18 N 2 O 5 S, (2) , are presented. These compounds are comprised of three types of rings: thia-zolidinone, nitrophenyl and cyclo-hexyl. In both structures, the rings are close to mutually perpendicular, with inter-planar dihedral angles greater than 80° in each case. The thia-zol-idinone rings in both structures exhibit envelope puckering with the S atom as flap and the cyclo-hexyl rings are in their expected chair conformations. The two structures superpose fairly well, except for the orientation of the nitro groups with respect to their host phenyl ring, with a difference of about 10° between 1 and 2 . The extended structure of 1 has two kinds of weak C-H⋯O inter-actions, giving rise to a closed ring formation involving three symmetry-related mol-ecules. Structure 2 has four C-H⋯O inter-actions, two of which are exclusively between symmetry-related thia-zolidinone dioxide moieties and have a parallel 'give-and-take-fashion' counterpart. In the other two inter-actions, the nitrophenyl ring and the cyclo-hexane ring each offer an H atom to the two O atoms on the sulfone group. Additionally, a C-H⋯π inter-action between a C-H group of the cyclo-hexane ring and the nitrophenyl ring of an adjacent mol-ecule helps to consolidate the structure.

Facile synthesis of 2-10 nm-sized graphene quantum dots (GQDs) from graphite powder by organic solvent-assisted liquid exfoliation using a sonochemical method is reported in this study. Synthesized GQDs are well dispersed in organic solvents like ethyl acetoacetate (EAA), dimethyl formamide (DMF) and also in water. MALDI-TOF mass spectrometry reveals its selective mass fragmentation. Detailed characterizations by various techniques like X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and high resolution transmission electron microscopy (HRTEM) confirm the formation of disordered, functional GQDs. Density functional theory (DFT) calculation confirms HOMO-LUMO energy gap variation with changing size and functionalities. Photoluminescence (PL) properties of as-prepared GQDs were studied in detail. The ensemble studies of GQDs showed excellent photoluminescence properties comprising normal and upconverted fluorescence, delayed fluorescence and room-temperature phosphorescence. PL decay dynamics of GQDs has been explored using time-correlated single-photon technique (TCSPC) as well as femtosecond fluorescence upconversion technique. In vitro cytotoxicity study reveals its biocompatibility and high cell viability (>91%) even at high concentration (400 μg mL(-1)) of GQDs in Chinese Hamster Ovary (CHO) cells.

Introduction: Securing an airway in maxillofacial injuries remains a challenge and is an important objective on the part of a maxillofacial surgeon to thoroughly understand its management., Purpose: The aim of this study was to evaluate the efficacy and complications of submental intubation in the management of midfacial/panfacial trauma patients where oro-endotracheal or naso-endotracheal intubation is contraindicated and tracheostomy can be avoided., Patients and Methods: Twenty patients with maxillofacial injuries were selected for submental intubation who were admitted in Kamineni Hospital, Narketpally, Nalgonda during a 2 year period (2010-2012). The parameters used to assess the efficacy were; restoration of the occlusion, duration of the surgery, presence of scar, presence of infection, damage to vital structures or any post-operative salivary fistula., Results: Submental intubation allowed reduction and fixation of all fractures without the interference of the tube during surgical procedure in all of the patients. There were no intra-operative complications and none of the patients required post-operative ventilation. There were no significant post-operative complications. However, in one of the cases (case 4) infection of submental wound was seen and in another case (case 11) salivary fistula was formed. Both the cases were appropriately managed without any difficulty. The submental scar was well accepted by all the patients., Conclusion: Submental intubation is a safe and extremely useful procedure in severe maxillofacial injuries. It presents a low incidence of operative and post operative complications. It allows both the surgeon and the anaesthetist to deliver a better quality of patient care.

Introduction: Fibro-osseous lesions are a diverse group of bone disorders and include developmental, reactive or dysplastic diseases and neoplasms. They share overlapping clinical, radiographic and histopathologic features and demonstrate a wide range of biological behaviour., Aim: To evaluate the characteristics, treatment and outcome of benign fibro-osseous lesions of the jaws., Patients and Method: All patients with fibro-osseous lesions of the jaws treated at the department of Oral and Maxillofacial Surgery of the Kamineni Institute of Dental Sciences from 2007 to 2013 were included in this study., Results: Six males and four females were treated. Juvenile ossifying fibroma was most often encountered (40 %), and the mandible was the most frequent location (70 %). Main clinical feature in most of the cases was a painless expansile swelling with facial asymmetry, and radiologically mixed (radiolucent and radiopaque lesions) were seen in majority of cases. All cases were surgically treated and histopathologically confirmed. Segmental ostectomy was performed in six cases; maxillectomy was done in one case and excision along with margin in three cases. Mean follow-up was of 3.3 years with no recurrence., Conclusions: Fibro-osseous lesions, although sharing similar microscopic features, exhibit a variety of clinical behavior rendering their treatment highly individualized. Radical treatment is the choice to achieve an outcome without recurrence.

Proline derivatives with a C(γ)-exo pucker typically display a high amide bond trans/cis (K(T/C)) ratio. This pucker enhances n→π* overlap of the amide oxygen and ester carbonyl carbon, which favors a trans amide bond. If there were no difference in n→π* interaction between the ring puckers, then the correlation between ring pucker and K(T/C) might be broken. To explore this possibility, proline conformations were constrained using a methylene bridge. We synthesized discrete gauche and anti 5-fluoro- and 5-hydroxy-N-acetylmethanoproline methyl esters from 3-syn and 3-anti fluoro- and hydroxymethanopyrrolidines using directed α-metalation to introduce the α-ester group. NBO calculations reveal minimal n→π* orbital interactions, so contributions from other forces might be of greater importance in determining K(T/C) for the methanoprolines. Consistent with this hypothesis, greater trans amide preferences were found in CDCl(3) for anti isomers en-MetFlp and en-MetHyp (72-78% trans) than for the syn stereoisomers ex-MetFlp and ex-MetHyp (54-67% trans). These, and other, K(T/C) results that we report here indicate how substituents on proline analogues can affect amide preferences by pathways other than ring puckering and n→π* overlap and suggest that caution should be exercised in assigning enhanced pyrrolidine C(γ)-exo ring puckering based solely on enhanced trans amide preference.

N-acetylmethanopyrrolidine methyl ester and its four 5-syn/anti-fluoro and hydroxy derivatives have been synthesized from 2-azabicyclo[2.2.0]hex-5-ene, a 1,2-dihydropyridine photoproduct. These conformationally constrained mimics of idealized C(β)-gauche and C(β)-anti conformers of pyrrolidines were prepared in order to determine the inherent bridge bias and subsequent heteroatom substituent effects upon trans/cis amide preferences. The bridgehead position and also the presence of gauche(syn)/anti-5-fluoro or 5-hydroxy substituents have minimal influence upon the K(T/C) values of N-acetylamide conformers in both CDCl(3) (43-54% trans) and D(2)O (53-58% trans). O-Benzoylation enhances the trans amide preferences in CDCl(3) (65% for a syn-OBz, 61% for an anti-OBz) but has minimal effect in D(2)O. The synthetic methods developed for N-BOC-methanopyrrolidines should prove useful in the synthesis of more complex derivatives containing α-ester substituents. The K(T/C) results obtained in this study establish baseline amide preferences that will enable determination of contributions of α-ester substituents to trans-amide preferences in methanoprolines.

Nucleophilic displacements of 5(6)-anti-bromo substituents in 2-azabicyclo[2.1.1]hexanes (methanopyrrolidines) have been accomplished. These displacements have produced 5-anti-X-6-anti-Y-difunctionalized-2-azabicyclo[2.1.1]hexanes containing bromo, fluoro, acetoxy, hydroxy, azido, imidazole, thiophenyl, and iodo substituents. Such displacements of anti-bromide ions require an amine nitrogen and are a function of the solvent and the choice of metal salt. Reaction rates were faster and product yields were higher in DMSO when compared to DMF and with CsOAc compared to NaOAc. Sodium or lithium salts gave products, except with NaF, where silver fluoride in nitromethane was best for substitution by fluoride. The presence of electron-withdrawing F, OAc, N(3), Br, or SPh substituents in the 6-anti-position slows bromide displacements at the 5-anti-position.

Noncovalent interactions define and modulate biomolecular structure, function, and dynamics. In many protein secondary structures, an intimate interaction exists between adjacent carbonyl groups of the main-chain amide bonds. As this short contact contributes to the energetics of protein conformational stability as well as protein-ligand interactions, understanding its nature is crucial. The intimacy of the carbonyl groups could arise from a charge-charge or dipole-dipole interaction, or n-->pi * electronic delocalization. This last putative origin, which is reminiscent of the Burgi-Dunitz trajectory, involves delocalization of the lone pairs (n) of the oxygen (O(i-1)) of a peptide bond over the antibonding orbital (pi*) of the carbonyl group (C(i)=O(i)) of the subsequent peptide bond. By installing isosteric chemical substituents in a peptidic model system and using NMR spectroscopy, X-ray diffraction analysis, and ab initio calculations to analyze the consequences, the intimate interaction between adjacent carbonyl groups is shown to arise primarily from n-->pi* electronic delocalization. This finding has implications for organic, biological, and medicinal chemistry.

Additions of iodonium-X reagents to N-alkoxycarbonyl-2-azabicyclo[2.2.1]hept-5-enes and the homologous 2-azabicyclo[2.2.2]oct-5-enes have been found to mirror the outcomes of additions of bromonium-X reagents. Only rearranged products were observed for reactions of either of these halonium ion reagents with the azabicylo[2.2.1]hept-5-enes. For the azabicyclo[2.2.2]oct-5-enes, nitrogen participation in addition of IOH or BrOH was dependent on the N-alkoxycarbonyl group. With larger N-Boc, N-Cbz, or N-Troc protecting groups, unrearranged 5-anti-hydroxy-6-syn-I(or Br)-2-azabicyclo[2.2.2]octanes were formed by nucleophilic attack at C(5) on syn-halonium ions. The structure of N-methyl-8-anti-bromo-4-anti-hydroxy-2-azabicyclo[3.2.1]octane has been reassigned by X-ray analysis.

The ability of Selectfluor to act as a nucleofuge for hydrolysis of beta-anti-halides was investigated with N-alkoxycarbonyl derivatives of 6-anti-Y-7-anti-X-2-azabicyclo[2.2.1]heptanes and 4-anti-Y-8-anti-X-6-azabicyclo[3.2.1]octanes. The azabicycles contained X = I or Br groups in the methano bridge and Y = F, Br, Cl, or OH substituents in the larger bridge. The relative reactivities of the halides were a function of the azabicycle, the halide, and its bridge and the addition of Selectfluor or HgF(2) as a nucleofuge. All halide displacements occurred with retention of stereochemistry. Selectfluor with sodium bromide or sodium chloride, but not sodium iodide, competitively oxidized some haloalcohols to haloketones. A significant 15.6 Hz F...HO NMR coupling was observed with 4-anti-fluoro-8-anti-hydroxy-6-azabicyclo[3.2.1]octane.

Novel 5-X-substituted-2-azabicyclo[2.1.1]hexanes (X = 5-syn-Cl, -Br, -I, -Ph, -NHCOOR (R = Me, Bn, t-Bu), -CH2CH2COOMe and X = 5-anti-Br, -I, -Ph) were synthesized from the X = 5-syn-carboxy derivative. New 5-anti-X-2-azabicyclo[2.1.1]hexanes, X = NHCOOR (R = Me, Bn), were prepared stereoselectively from the X = 5-anti-carboxy substrate.