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The aminopeptidase, endoplasmic reticulum aminopeptidase 1 (ERAP1), trims peptides for loading into major histocompatibility complex class I (MHC class I), and loss of this activity has broad effects on the MHC class I peptidome. Here, we investigated the impact of targeting ERAP1 in immune checkpoint blockade (ICB), as MHC class I interactions mediate both activating and inhibitory functions in antitumor immunity. Loss of ERAP sensitized mouse tumor models to ICB, and this sensitivity depended on CD8 + T cells and natural killer (NK) cells. In vivo suppression screens revealed that Erap1 deletion inactivated the inhibitory NKG2A-HLA-E checkpoint, which requires presentation of a restricted set of invariant epitopes (VL9) on HLA-E. Loss of ERAP altered the HLA-E peptidome, preventing NKG2A engagement. In humans, ERAP1 and ERAP2 showed functional redundancy for the processing and presentation of VL9, and loss of both inactivated the NKG2A checkpoint in cancer cells. Thus, loss of ERAP phenocopies the inhibition of the NKG2A-HLA-E pathway and represents an attractive approach to inhibit this critical checkpoint., Competing Interests: Declaration of interests This manuscript is the result of a collaborative effort between the Broad Institute and Calico Life Sciences, LLC and was supported by funding from Calico Life Sciences, LLC. K.J.F., M.M.S., M.C., N.O., F.E.M., A.F., D.S., and F.A.H. are current employees of Calico Life Science, LLC. S.K. was an employee of Broad Institute at the time she contributed to the work and is a current employee of Genentech. M.F.P. was an employee of Calico Life Sciences at the time he contributed to the work and is a current employee of TenSixteen Bio. W.S. was an employee of Calico Life Sciences at the time she contributed to the work. A.I.-V. was an employee of the Broad Institute at the time he contributed to the work and is a current employee of Monte Rosa Therapeutics. T.G.R.D. was an employee of the Broad Institute at the time he contributed to the work and is a current employee of Tessera Therapeutics. T.A. was an employee of the Broad Institute at the time she contributed to the work and is a current employee of ZS. T.B.S. was an employee of the Broad Institute at the time he contributed to the work and is a current employee of Johnson & Johnson Innovative Medicine. R.T.M. has received speaking or consulting fees from Bristol Myers Squibb, Gilead Sciences, Kumquat Biosciences, and Immunai Therapeutics and has equity ownership in OncoRev, LLC. Calico Life Sciences, LLC and the Broad Institute participated in the interpretation of data, review, and approval of the publication., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Submarine groundwater discharge is a pivotal factor in modifying the structure of phytoplankton communities in coastal waters. The objective of the study was to investigate how variations in nutrient concentrations and ratios influence the composition of phytoplankton communities along the coastal waters of Bay of Bengal. The experiment involved mixing groundwater with coastal water at 5 % and 10 % proportions. Phytoplankton growth was more pronounced in 10 % groundwater than those with 5 % and control samples. In control samples, Chl-a and other pigments, experienced decrease from 20 % to 80 %, except in Odisha-Paradeep and Visakhapatnam-Andhra Pradesh, where peridinin concentrations increased by 60 % to 65 % owing to low Si:N ratios below 0.2. A shift was observed from diatoms to dinoflagellates due to low Si: N ratios. The results reaffirm the hypothesis that variations in nutrient concentrations and ratios play a substantial role in shaping the composition of phytoplankton in the adjacent coastal waters., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the research reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Comprehensive and in-depth identification of the human leukocyte antigen class I (HLA-I) and class II (HLA-II) tumor immunopeptidome can inform the development of cancer immunotherapies. Mass spectrometry (MS) is a powerful technology for direct identification of HLA peptides from patient-derived tumor samples or cell lines. However, achieving sufficient coverage to detect rare and clinically relevant antigens requires highly sensitive MS-based acquisition methods and large amounts of sample. While immunopeptidome depth can be increased by off-line fractionation prior to MS, its use is impractical when analyzing limited amounts of primary tissue biopsies. To address this challenge, we developed and applied a high-throughput, sensitive, and single-shot MS-based immunopeptidomics workflow that leverages trapped ion mobility time-of-flight MS on the Bruker timsTOF single-cell proteomics system (SCP). We demonstrate greater than twofold improved coverage of HLA immunopeptidomes relative to prior methods with up to 15,000 distinct HLA-I and HLA-II peptides from 4e7 cells. Our optimized single-shot MS acquisition method on the timsTOF SCP maintains high coverage, eliminates the need for off-line fractionation, and reduces input requirements to as few as 1e6 A375 cells for >800 distinct HLA-I peptides. This depth is sufficient to identify HLA-I peptides derived from cancer-testis antigen and noncanonical proteins. We also apply our optimized single-shot SCP acquisition methods to tumor-derived samples, enabling sensitive, high-throughput, and reproducible immunopeptidome profiling with detection of clinically relevant peptides from less than 4e7 cells or 15 mg wet weight tissue., Competing Interests: Conflict of interest S. A. C. is a member of the scientific advisory boards of Kymera, PTM BioLabs, Seer, and PrognomIQ. A.S.V.J. is an employee of Bruker. All other authors declare no competing interests., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Many high-risk conditions of pregnancy are undetected until the time of delivery in low-income countries. We developed a point-of-care ultrasound training protocol for providers in rural Uganda to detect fetal distress or demise, malpresentation, multiple gestation, placenta previa, oligohydramnios and preterm delivery. This was a mixed-methods study to evaluate the 2-week training curriculum and trainees' ability to perform a standard scanning protocol and interpret ultrasound images. Surveys to assess provider confidence were administered pre-training, immediately after, and at 3-month follow up. Following lecture and practical demonstrations, each trainee conducted 25 proctored scans and were required to pass an observed structured clinical exam (OSCE). All images produced 8 weeks post course underwent blinded review by two ultrasound experts to assess image quality and to identify common errors. Key informant interviews further assessed perceptions of the training program and utility of point-of-care ultrasound. All interviews were audio recorded, transcribed, and reviewed by multiple readers using a content analysis approach. Twenty-three nurse/nurse midwives and two physicians from one district hospital and three health centers participated in the training curriculum. Confidence levels increased from an average of 1 point pre-course to over 6 points post-course for all measures (maximum of 7 points). Of 25 participants, 22 passed the OSCE on the first attempt (average score 89.4%). Image quality improved over time; the final error rate at week 8 was less than 5%, with an overall kappa of 0.8-1 for all measures between the two reviewers. Among the 12 key informant interviews conducted, key themes included a desire for more hands-on training and longer duration of training and challenges in balancing clinical duties with ability to attend training sessions. This study demonstrates that providers without previous ultrasound experience can detect high-risk conditions during labor with a high rate of quality and accuracy after training., Competing Interests: No authors have competing interests.

The CaFe 2 O 4 nanoparticles (CFNP) were synthesized using the solution combustion method. The CFNP-chitosan-ampicillin was prepared by the ionic gelation method using tripolyphosphate (TPP). The CFNP, chitosan-CFNP, chitosan-CFNP-ampicillin materials were characterized by XRD, FT-IR and TGA analysis in order to evaluate the particle nature and size, the presence of functional groups and their thermal stability. The FESEM and EDAX analysis were performed to understand the surface morphology of the materials and the presence of CFNP in the material, respectively. The vibrating sample magnetometer (VSM) analysis was performed to analyze the magnetic property of the chitosan-CFNP material. The squareness value of 0.1733 obtained by VSM measurements indicates the super paramagnetic nature of chitosan-CFNP. Taguchi orthogonal array method was applied to identify the significant impacting parameters for maximizing the drug encapsulation of chitosan-CFNP. The drug release studies showed that the drug was released rapidly in acidic medium as compared to the basic or neutral medium. The drug release kinetic data were fitted with different linear kinetic model equations and the best fit was obtained with Korsmeyer-Peppas model. The model drug ampicillin release from chitosan-CFNP was tested against staphylococcus epidermis bacteria through disc diffusion method for checking biocompatibility and antibacterial activity., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Background: The diagnosis and management of acutely dyspneic patients in resource-limited developing world settings poses a particular challenge. Focused cardiopulmonary ultrasound (CPUS) may assist in the emergency diagnosis and management of patients with acute dyspnea by identifying left ventricular systolic dysfunction, pericardial effusion, interstitial pulmonary edema, and pleural effusion. We sought to assess the accuracy of emergency providers performing CPUS after a training intervention in a limited-resource setting; a secondary objective was to assess the ability of CPUS to affect change of clinician diagnostic assessment and acute management in patients presenting with undifferentiated dyspnea., Methods and Results: After a training intervention for Haitian emergency providers, patients with dyspnea presenting urgently to a regional referral center in Haiti underwent a rapid CPUS examination by the treating physician. One hundred seventeen patients (median age of 36 years, 56 % female) were prospectively evaluated with a standardized CPUS exam. Blinded expert review of ultrasound images was performed by two board certified cardiologists and one ultrasound fellowship trained emergency physician. Inter-observer agreement was determined using an agreement coefficient (kappa). Sensitivity and Specificity with confidence intervals were calculated. Pre-test and post-test clinician impressions and management plans were compared to assess for a change. We enrolled 117 patients with undifferentiated dyspnea. Upon expert image review, prevalence of left ventricular systolic dysfunction was 40.2 %, and in those with systolic dysfunction, the average EF was 14 % (±9 %). The parasternal long axis (PLAX) single view was predictive of an overall abnormal echo with PPV of abnormal PLAX 95 % and NPV 93 % of normal PLAX. Weighted kappa for pericardial effusion between the Haitian physicians and two cardiology reviewers was 0.81 (95 % CI 0.75-0.87, p value <0.001) and for ejection fraction was 0.98 (95 % CI 0.98-0.99, p value <0.001). For lung ultrasound, a kappa statistic assessing agreement between the Haitian physician and the EP for pleural effusion was 0.73, and for interstitial syndrome was 0.49. Detailed test characteristics are detailed in Table 3. Overall, there was a change in treating clinician impression in 15.4 % (95 % CI 9-22 %) and change in management in 19.6 % (95 % CI 12-27 %) of patients following CPUS. A significant structural heart disease was common: 48 % of patients were noted to have abnormal right ventricular systolic function, 36 % had at least moderate mitral regurgitation, and 7.7 % had a moderate to large pericardial effusion., Conclusions: A focused training intervention in CPUS was sufficient for providers in a limited-resource setting to accurately identify left ventricular systolic dysfunction, pericardial effusion, evidence of interstitial syndrome, and pleural effusions in dyspneic patients. Clinicians were able to integrate CPUS into their clinical impressions and management plans and reported a high level of confidence in their ultrasound findings.

The present investigation attempts at fabricating collagen-based scaffolds impregnated with sago starch capped silver nanoparticles (AgNPs), useful for biomedical applications, and aims at studying their physicochemical aspects. AgNPs synthesized through a chemical reduction method, capped using different concentrations of sago starch, are incorporated into collagen derived from fish scales, and lyophilized to form scaffolds. FT-IR spectra confirm and validate the interaction of sago starch capped AgNPs with collagen in the scaffolds. TGA and DSC results indicate enhanced thermal stability of collagen scaffolds impregnated with sago capped AgNPs compared to collagen alone. All the collagen scaffolds containing sago starch capped AgNPs show high tensile strength values for their use as wound dressing materials. Moreover, lower minimum inhibitory concentration values are obtained for the above capped AgNP collagen scaffolds, which indicate higher antibacterial activities compared to uncapped AgNPs tested against both gram positive and negative bacterial strains. The novelty is that the developed scaffolds are biodegradable and in vitro studies reveal them as biocompatible and suitable for tissue regeneration applications.

Novel bio-renewable castor oil based polyurethane (PU)-silica nanocomposite films were prepared using castor oil, 1,6-hexamethylene diisocyanate and dibutyltin dilaurate in tetrahydrofuran at room temperature. ATR-FTIR spectra confirm the formation of polyurethane and the presence of silica nanoparticles in the polyurethane matrix. The increase of Si nanoparticle content shifts the peak position of N-H and C[double bond, length as m-dash]O (both hydrogen and non-hydrogen bonded) groups present in the polyurethane structure. Furthermore, Raman spectra confirmed the urethane-amide interaction present in the polyurethane-silica nanocomposites. (29)Si CP/MAS NMR spectra evidence the formation and the presence of completely condensed SiO2 species in the polyurethane nanocomposite films. The incorporation of silica nanoparticles increases the thermal stability of the above-mentioned polyurethane films, which can be seen from the increase in activation energy (Ea) values of the degradation process. The Ea values at two stages (Tmax1 and Tmax2) of the degradation process are 133, 139 and 157, 166 kJ mol(-1) for PU control and PU-5AMS (5 wt% amine modified silica nanoparticles), respectively. DSC results prove the interfacial interaction present between silica nanoparticles and the polyurethane hard segment, which decreases the melting temperature. Optical transmittance of the polyurethane films decreased with increasing silica content due to the scattering at the interfaces between the silica nanoparticles and polyurethane. It is interesting to note that the presence of silica nanoparticles gives reinforcement to polyurethane film, thereby increasing the storage modulus up to 24% for PU-5AMS. FE-SEM and HR-TEM images confirm the presence of silica nanoparticles in the polyurethane matrix.

We report a simple and facile method to prepare a novel pH sensitive polyampholyte nanogel by copolymerizing vinylimidazole (VIM) with acrylic acid (AA) using functionalized single-walled carbon nanotubes (f-SWCNTs) (as reinforcing material) and cyanuric chloride via an intermolecular quaternization reaction. The polyampholyte nanogels have been characterized by various microscopic and spectroscopic methods. These studies reveal that incorporation of nanotubes in cross-linked copolymer of poly(vinylimidazole-co-acrylic acid) (PVI-co-AA) form polyampholyte nanogel with enhanced physical properties. The thermal experiments show that the introduction of f-SWCNTs into PVI-co-AA has significant impact on the thermal stability of nanogels. The rheological study showed that the nanogel is more viscoelastic than native gel. MTT assay indicates that the prepared polyampholyte gels possess biocompatibility and cell viability. The nanogel is also useful material to load water-soluble drug such as promethazine hydrochloride. The releasing profile of the drug from the nanogel clearly shows the pH-sensitive property of the material., (Copyright © 2013 Elsevier B.V. All rights reserved.)

A series of castor oil based polyurethane/siloxane cross-linked films were prepared using castor oil, isophorone diisocyanate, and 3-aminopropyl trimethoxysilane by the sol-gel process. Fourier transform infrared (FT-IR) spectra reveal the cross-linking interaction between polyurethane and siloxane moieties, thereby shifting the peak position of characteristic N-H and C═O groups to higher wavenumber. (29)Si (silica) solid state nuclear magnetic resonance spectra were used to prove the formation of siloxane network linkage in the polyurethane system, thereby analyzing the Si environment present in the polyurethane/siloxane cross-linked films. The activation energy values at two stages (Tmax1 and Tmax2) for the degradation of polyurethane films were increased with increasing silane ratio. The calculated activation energy values for the higher silane ratio (1.5) are 136 and 170 kJ/mol at Tmax1 and Tmax2, respectively. From contact angle measurements, we observed that increasing siloxane cross-linking increased the hydrophobicity of the films. The optical transmittance obtained from ultraviolet-visible spectra indicated that the film samples are transparent in the region 300-800 nm. The moisture sorption/desorption isotherm curve shows a characteristic behavior of type III isotherm corresponds to hydrophobic materials. Dynamic mechanical studies show that the increase in storage modulus reveals siloxane cross-linking gives rigidity to the films. Atomic force microscopic images show that the introduction of siloxane changes the surface roughness of the polyurethane films. It is found that the siloxane cross-linking can be used to obtain hydrophobic surface films having good thermal stability and optical transmittance.

Sol-gel silica/nanoclay composites were prepared through sol-gel polymerization technique using tetraethylorthosilicate precursor and montmorillonite (MMT) clay in aqueous media. In this study, both montmorillonite-K(+) and organically modified MMT (OMMT) clays were used. The prepared composites were coated on glass substrate by making 1 wt% solution in ethyltrichlorosilane. The incorporation of nanoclay does not alter the intensity of characteristic Si-O-Si peak of silica network. Thermogravimetric studies show that increasing clay content increased the degradation temperature of the composites. Differential scanning calorimetry (DSC) results of organically modified MMT nanoclay incorporated composite show a shift in the melting behavior up to 38°C. From DSC thermograms, we observed that the ΔH value decreased with increasing clay loading. X-ray diffraction patterns prove the presence of nanoclay in the composite and increase in the concentration of organically modified nanoclay from 3 to 5 wt% increases the intensity of the peak at 2θ=8° corresponds to OMMT. Morphology of the control silica gel composite was greatly influenced by the incorporation of OMMT. The presence of nanoclay changed the surface of control silica gel composite into cleaved surface with brittle in nature. Contact angle measurements were done for the coatings to study their surface behavior. These hybrid coatings on glass substrate may have applications for hydrophobic coatings on leather substrate., (Copyright © 2011 Elsevier B.V. All rights reserved.)

In this paper, we report the preparation and characterization of mesoporous and biocompatible transparent silica aerogel by the sol-gel polymerization of tetraethyl orthosilicate using ionic liquid. Choline cation based ionic liquid allows the silica framework to form in a non collapsing environment and controls the pore size of the gel. FT-IR spectra reveal the interaction of ionic liquid with surface -OH of the gel. DSC thermogram giving the evidence of confinement of ionic liquid within the silica matrix, which helps to avoid the shrinkage of the gel during the aging process. Nitrogen sorption measurements of gel prepared with ionic liquid exhibit a low surface area of 100.53 m2/g and high average pore size of 3.74 nm. MTT assay proves the biocompatibility and cell viability of the prepared gels. This new nanoporous silica material can be applied to immobilize biological molecules, which may retain their stability over a longer period., (Copyright © 2011 Elsevier B.V. All rights reserved.)