Mosaic Atoh1 deletion in the chick auditory epithelium reveals a homeostatic mechanism to restore hair cell number.

The mechanosensory hair cell of the vertebrate inner ear responds to the mechanical deflections that result from hearing or change in the acceleration due to gravity, to allow us to perceive and interpret sounds, maintain balance and spatial orientation. In mammals, ototoxic compounds, disease, and acoustic trauma can result in damage and extrusion of hair cells, without replacement, resulting in hearing loss. In contrast, non-mammalian vertebrates can regenerate sensory hair cells. Upon damage, hair cells are extruded and an associated cell type, the supporting cell is transformed into a hair cell. The mechanisms that can trigger regeneration are not known. Using mosaic deletion of the hair cell master gene, Atoh1, in the embryonic avian inner ear, we find that despite hair cells depletion at E9, by E12, hair cell number is restored in sensory epithelium. Our study suggests a homeostatic mechanism can restores hair cell number in the basilar papilla, that is activated when juxtracrine signalling is disrupted. Restoration of hair cell numbers during development may mirror regenerative processes, and our work provides insights into the mechanisms that trigger regeneration.

Complex Pathways Drive Pluripotent Fmoc-Leucine Self-Assemblies.

Nature uses complex self-assembly pathways to access distinct functional non-equilibrium self-assemblies. This remarkable ability to steer same set of biomolecules into different self-assembly states is done by avoiding thermodynamic pit. In synthetic systems, on demand control over 'Pathway Complexity' to access self-assemblies different from equilibrium structures remains challenging. Here we show versatile non-equilibrium assemblies of the same monomer via alternate assembly pathways. The assemblies nucleate using non-classical or classical nucleation routes into distinct metastable (transient hydrogels), kinetic (stable hydrogels) and thermodynamic structures [(poly)-crystals and 2D sheets]. Initial chemical and thermal inputs force the monomers to follow different assembly pathways and form soft-materials with distinct molecular arrangements than at equilibrium. In many cases, equilibrium structures act as thermodynamic sink which consume monomers from metastable structures giving transiently formed materials. This dynamics can be tuned chemically or thermally to slow down the dissolution of transient hydrogel, or skip the intermediate hydrogel altogether to reach final equilibrium assemblies. If required this metastable state can be kinetically trapped to give strong hydrogel stable over days. This method to control different self-assembly states can find potential use in similar biomimetic systems to access new materials for various applications.

Polymorphic residues in HLA-B that mediate HIV control distinctly modulate peptide interactions with both TCR and KIR molecules.

Immunogenetic studies have shown that specific HLA-B residues (67, 70, 97, and 156) mediate the impact of HLA class I on HIV infection, but the molecular basis is not well understood. Here we evaluate the function of these residues within the protective HLA-B∗5701 allele. While mutation of Met67, Ser70, and Leu156 disrupt CD8+ T cell recognition, substitution of Val97 had no significant impact. Thermal denaturation of HLA-B∗5701-peptide complexes revealed that Met67 and Leu156 maintain HLA-peptide stability, while Ser70 and Leu156 facilitate T cell receptor (TCR) interactions. Analyses of existing structures and structural models suggested that Val97 mediates HLA-peptide binding to inhibitory KIR3DL1 molecules, which was confirmed by experimental assays. These data thereby demonstrate that the genetic basis by which host immunity impacts HIV outcomes occurs by modulating HLA-B-peptide stability and conformation for interaction with TCR and killer immunoglobulin receptor (KIR) molecules. Moreover, they indicate a key role for epitope specificity and HLA-KIR interactions to HIV control.

Validation and Estimation of Obesity-Induced Intervertebral Disc Degeneration through Subject-Specific Finite Element Modelling of Functional Spinal Units.

(1) Background: Intervertebral disc degeneration has been linked to obesity; its potential mechanical effects on the intervertebral disc remain unknown. This study aimed to develop and validate a patient-specific model of L3-L4 vertebrae and then use the model to estimate the impact of increasing body weight on disc degeneration. (2) Methods: A three-dimensional model of the functional spinal unit of L3-L4 vertebrae and its components were developed and validated. Validation was achieved by comparing the range of motions (RoM) and intradiscal pressures with the previous literature. Subsequently, the validated model was loaded according to the body mass index and estimated stress, deformation, and RoM to assess disc degeneration. (3) Results: During validation, L3-L4 RoM and intradiscal pressures: flexion 5.17° and 1.04 MPa, extension 1.54° and 0.22 MPa, lateral bending 3.36° and 0.54 MPa, axial rotation 1.14° and 0.52 MPa, respectively. When investigating the impact of weight on disc degeneration, escalating from normal weight to obesity reveals an increased RoM, by 3.44% during flexion, 22.7% during extension, 29.71% during lateral bending, and 33.2% during axial rotation, respectively. Also, stress and disc deformation elevated with increasing weight across all RoM. (4) Conclusions: The predicted mechanical responses of the developed model closely matched the validation dataset. The validated model predicts disc degeneration under increased weight and could lay the foundation for future recommendations aimed at identifying predictors of lower back pain due to disc degeneration.

Biodiesel production and exploring properties of Datura stramonium L. oil with its optimization using combined approaches-Taguchi, grey relational analysis, and response surface methodology.

Biodiesel production through the synthesis of Datura stramonium L. oil is studied to explore the most efficient approaches to suggest an alternate feedstock for biodiesel production. The main objective of this work is to optimize the process variables of biodiesel synthesis by using some statistical approach (Taguchi method, grey relational analysis (GRA), and response surface methodology (RSM) analyzing three parameters, i.e., alcohol-to-oil molar ratio, catalyst (NaOH) concentration, and process temperature for achieving maximum biodiesel derived from Datura stramonium L. oil. The transesterification process is applied by using an ultrasonic-assisted technique. Grey relational analysis (GRA) was successfully applied with the Taguchi method resulting in the optimum combination of A2B1C1. Based on the findings, the best operating conditions for transesterifying are attained with the RSM approach consisting of a 5.697:1 molar ratio (level 2), 0.3 (wt.%) NaOH concentration (level 1), and 70 °C process temperature (level 1). With a value of 87.02%, these ideal operating conditions produce the maximum yield as compared to grey relational analysis (GRA) yields 83.99%. The obtained results have been verified through the characterization of oil and biodiesel as well. Also, the fuel qualities of DSL biodiesel were identified and assessed. DSL oil was found 137.6 degrees of unsaturation during fatty acid profile analysis. DSL biodiesel was found the best kinematic viscosity (4.2 mm2/s) and acid value (0.49) when compared to Karanja and palm biodiesel. D. stramonium L. was recognized as a suitable species for biodiesel feedstock according to the findings.

No Correlation Exists Between Tibial- and Femoral-Based Measurements of Patella Alta in a Population With Chronic Patellofemoral Pain or Instability Undergoing Patella Distalization.

PURPOSE: To investigate whether the patellotrochlear index (PTI) predicts patella alta as determined by tibial-based methods of Insall-Salvati (IS) and Caton-Deschamp (CDI) indexes in a pathological population (with patellofemoral pain and/or instability), in addition to determining whether PTI and sagittal patellofemoral engagement (SPE) correlate with trochlea length as determined by lateral condyle index (LCI). METHODS: Patients with confirmed patella alta (IS/CDI ratio >1.2) undergoing tibial tubercle osteotomy for patellofemoral pain/instability with an available magnetic resonance imaging (MRI) scans were included. Patients who had undergone previous soft-tissue realignment, previous surgery, or trauma to the extensor mechanism were excluded. Two raters measured the IS, CDI, PTI, SPE, LCI, and knee flexion angle (KFA) on MRI. Interobserver reliability and correlation between measurements were calculated. RESULTS: In total, 71 knees were included. PTI (0.73), SPE (0.836), LCI (0.701), and KFA (0.8) demonstrated good- to near-excellent interobserver reliability. IS (0.65) and CDI (0.66) demonstrated moderate interobserver reliability. PTI and SPE showed the strongest significant correlation (0.8112, P = 2.2 × 10-16). IS and CD (0.39, P = .0007) showed a moderate significant correlation. PTI and KFA (0.53, P = 1.685 × 10-6) and SPE and KFA (0.61, P = 1.991 × 10-8) had a significant moderate correlation. LCI and KFA (-0.37, P = .0017) showed a significant moderate negative correlation. All other measurement indices correlated poorly and were insignificant. A total of 94.4% of the knees were defined as having patella alta using IS, with the remaining 5.6% having a raised CDI. Only 14% of cases had an IS of >1.2, a CDI >1.2, and a PTI <0.125, which increased to 39% (28/71) when the threshold for PTI was increased to <0.28. CONCLUSIONS: There was no correlation between tibial (IS and CD) and femoral methods (PTI and SPE) of quantifying patella alta. PTI and SPE did not correlate with trochlea length as measured by LCI. PTI, SPE, and LCI are significantly affected by the KFA during MRI. LEVEL OF EVIDENCE: Level IV, retrospective diagnostic radiographic investigation.

A compact SiGe D-band power amplifier for scalable photonic-enabled phased antenna arrays.

To address the rising demand for high-speed wireless data links, communication systems operating at frequencies beyond [Formula: see text] are being targeted. A key enabling technology in the development of these wireless systems is the phased antenna array. Yet, the design and implementation of such steerable antenna arrays at frequencies over [Formula: see text] comes with a multitude of challenges. In particular, the cointegration of active electronics at each antenna element poses a major hurdle due to the inherent space constraints in the array. This article proposes a novel scalable concept for opto-electronic phased antenna arrays operating at 140 GHz. It details the system architecture of a transmitter that enables the implementation of large scale, wideband, 2D steerable phased antenna arrays and presents the design and measurement of a compact SiGe power amplifier (PA) chip to be used as one of its key building blocks. The amplifier achieves a gain of 20 dB at 135 GHz, features a [Formula: see text] of 14.6 dBm and can support data rates up to 45 Gbps in a limited footprint of only 540µm × 550µm. This makes it one of the fastest, most powerful D-band power amplifiers in literature with a footprint compatible with [Formula: see text]-spaced phased array integration.

EgoActive: Integrated Wireless Wearable Sensors for Capturing Infant Egocentric Auditory-Visual Statistics and Autonomic Nervous System Function 'in the Wild'.

There have been sustained efforts toward using naturalistic methods in developmental science to measure infant behaviors in the real world from an egocentric perspective because statistical regularities in the environment can shape and be shaped by the developing infant. However, there is no user-friendly and unobtrusive technology to densely and reliably sample life in the wild. To address this gap, we present the design, implementation and validation of the EgoActive platform, which addresses limitations of existing wearable technologies for developmental research. EgoActive records the active infants' egocentric perspective of the world via a miniature wireless head-mounted camera concurrently with their physiological responses to this input via a lightweight, wireless ECG/acceleration sensor. We also provide software tools to facilitate data analyses. Our validation studies showed that the cameras and body sensors performed well. Families also reported that the platform was comfortable, easy to use and operate, and did not interfere with daily activities. The synchronized multimodal data from the EgoActive platform can help tease apart complex processes that are important for child development to further our understanding of areas ranging from executive function to emotion processing and social learning.

Expression of miR-145 and miR-18b in Peripheral Blood Samples of Head and Neck Cancer Patients.

Head and neck squamous cell carcinomas (HNSCC) is one of the most prevalent type of cancer known in Indian population. Studies are needed to identify the early biomarkers for HNSCC. MicroRNAs (miRNAs) are non-coding RNA molecules, expression of which can be used as biomarker for early diagnosis of HNSCC. For miRNA profiling total RNA, which also contained small RNAs were isolated from ten HNSCC tissue samples and adjacent control. Purity and concentration of eluted RNA was assessed using the NanoDrop1000® spectrophotometer, Reverse Transcription reaction was carried out with megaplex RT primers of pool A and pool B and the expression of selected miRNAs (miR-143/145 and miR-18a/b) was measured using TaqMan primers specific for mature miRNAs. Our study showed dramatic downregulation in expression of two miRNAs, miR-18b and miR-145 in blood samples of HNSCC patients, which are inhibitor of tumorigenesis and can be targeted as biomarker of HNSCC pathogenesis therefore developing avenues for miRNA role in prognosis and therapeutics. Supplementary Information: The online version contains supplementary material available at 10.1007/s12291-023-01119-2.

High-throughput characterization of HLA-E-presented CD94/NKG2x ligands reveals peptides which modulate NK cell activation.

HLA-E is a non-classical class I MHC protein involved in innate and adaptive immune recognition. While recent studies have shown HLA-E can present diverse peptides to NK cells and T cells, the HLA-E repertoire recognized by CD94/NKG2x has remained poorly defined, with only a limited number of peptide ligands identified. Here we screen a yeast-displayed peptide library in the context of HLA-E to identify 500 high-confidence unique peptides that bind both HLA-E and CD94/NKG2A or CD94/NKG2C. Utilizing the sequences identified via yeast display selections, we train prediction algorithms and identify human and cytomegalovirus (CMV) proteome-derived, HLA-E-presented peptides capable of binding and signaling through both CD94/NKG2A and CD94/NKG2C. In addition, we identify peptides which selectively activate NKG2C+ NK cells. Taken together, characterization of the HLA-E-binding peptide repertoire and identification of NK activity-modulating peptides present opportunities for studies of NK cell regulation in health and disease, in addition to vaccine and therapeutic design.

Decoupled neoantigen cross-presentation by dendritic cells limits anti-tumor immunity against tumors with heterogeneous neoantigen expression.

Cancer immunotherapies, in particular checkpoint blockade immunotherapy (CBT), can induce control of cancer growth, with a fraction of patients experiencing durable responses. However, the majority of patients currently do not respond to CBT and the molecular determinants of resistance have not been fully elucidated. Mounting clinical evidence suggests that the clonal status of neoantigens (NeoAg) impacts the anti-tumor T cell response. High intratumor heterogeneity (ITH), where the majority of NeoAgs are expressed subclonally, is correlated with poor clinical response to CBT and poor infiltration with tumor-reactive T cells. However, the mechanism by which ITH blunts tumor-reactive T cells is unclear. We developed a transplantable murine lung cancer model to characterize the immune response against a defined set of NeoAgs expressed either clonally or subclonally to model low or high ITH, respectively. Here we show that clonal expression of a weakly immunogenic NeoAg with a relatively strong NeoAg increased the immunogenicity of tumors with low but not high ITH. Mechanistically we determined that clonal NeoAg expression allowed cross-presenting dendritic cells to acquire and present both NeoAgs. Dual NeoAg presentation by dendritic cells was associated with a more mature DC phenotype and a higher stimulatory capacity. These data suggest that clonal NeoAg expression can induce more potent anti-tumor responses due to more stimulatory dendritic cell:T cell interactions. Therapeutic vaccination targeting subclonally expressed NeoAgs could be used to boost anti-tumor T cell responses.

Cellulose-based bioabsorbable and antibiotic coated surgical staple with bioinspired design for efficient wound closure.

The quest to design a flawless wound closure system began long ago and is still underway. Introducing surgical staples is one of the most significant breakthroughs in this effort. In this work, we developed a biodegradable surgical staple to meet the optimal wound closure system criteria and other clinical requirements, such as radiography compatibility and secondary infection prevention. To meet these requirements, a naturally derived cellulose acetate (CA) fiber-reinforced poly-(l-lactic acid) (PLLA) composite was synthesized, and its physicochemical properties were determined using several characterizations such as Fourier-transform infrared spectroscopy (FTIR), Differential scanning calorimetry (DSC) and Universal testing machine (UTM), etc. Taking cues from the Mantis's foreleg, a novel staple design was implemented and verified using Finite Element Analysis (FEA). The CA + PLLA staples were fabricated using melt-casted/3D-printing processes. The staples exhibited excellent biodegradation in both wound and physiological microenvironments with sufficient puncturing strength and later closed the wound's edges mechanically. In addition, the CA + PLLA staples also exhibit metal-like ductility properties to withstand horizontal skin tensions during the healing process. Further, the staples are coated with an antibiotic to combat infections effectively to provide better healing.

Role of Transcription Factor BEND3 and Its Potential Effect on Cancer Progression.

BEND3 is a transcription factor that plays a critical role in the regulation of gene expression in mammals. While there is limited research on the role of BEND3 as a tumor suppressor or an oncogene and its potential role in cancer therapy is still emerging, several studies suggest that it may be involved in both the processes. Its interaction and regulation with multiple other factors via p21 have already been reported to play a significant role in cancer development, which serves as an indication of its potential role in oncogenesis. Its interaction with chromatin modifiers such as NuRD and NoRC and its role in the recruitment of polycomb repressive complex 2 (PRC2) are some of the additional events indicative of its potential role in cancer development. Moreover, a few recent studies indicate BEND3 as a potential target for cancer therapy. Since the specific mechanisms by which BEND3 may contribute to cancer progression are not yet fully elucidated, in this review, we have discussed the possible pathways BEND3 may take to serve as an oncogenic driver or suppressor.

Comparison between all-on-four and all-on-six treatment concepts on stress distribution for full-mouth rehabilitation using three-dimensional finite element analysis: A biomechanical study.

Purpose: The current study intended to provide a comparison of biomechanical behaviors of two different treatment concepts for full-mouth rehabilitation with dental implants placed according to the "All-on-four" concept and "All-on-six" concept with analysis of the stress patterns of the implant support system using three-dimensional finite element analysis (FEA). Materials and Methods: The edentulous mandible was treated with two different implant designs. "All-on-Four" implant placement concept was used in Model 1 with two central axial implants and two distally tilted implants at 17° and in Model 2, "All-on-Six" concept was applied with six vertically placed implants. Individual vertical and horizontal load of 100 N and oblique load of 141 N at 45° was applied to all implants. To evaluate and compare the results in terms of maximum principal stress, we used FEA. Results: All-on-six showed smaller maximum principal stress values on the cortical bone and implants. However, maximum principal stress values obtained on trabecular bone was smaller in the All-on-four design for vertical and horizontal loading conditions. Conclusions: The All-on-six approach showed more favorable biomechanical behavior.

Transcriptomics and Proteomics Approach for the Identification of Altered Blood microRNAs and Plasma Proteins in Parkinson's Disease.

Parkinson's disease (PD) is a neurodegenerative disorder caused by the selective destruction of dopaminergic neurons (DA-nergic). Clinically, PD is diagnosed based on developing signs and symptoms. A neurological and physical examination and sometimes medical and family history also help in the diagnosis of PD. However, most of these features are visible when more than 80% of the dopaminergic neurons have degenerated. An understanding of the selective degeneration process at the cellular and molecular level and the development of new biomarkers are required for effective PD management. Several studies have been carried out using a selected set of miRNAs/ mRNAs and proteins to develop biomarkers of PD; however, an unbiased and combined miRNA-protein profiling study was required to identify the markers of progressive and selected degeneration of dopaminergic neurons in PD patients. In the present study, we have carried out global protein profiling through LC-MS/MS and miRNA profiling by using a "brain-specific" miRNA array panel of 112 miRNAs in PD patients and healthy controls to find the unprejudiced group of proteins and miRNAs that are deregulating in PD. In the whole blood samples of PD patients compared to healthy controls, the expression of 23 miRNAs and 289 proteins was significantly increased, whereas the expression of 4 miRNAs and 132 proteins was considerably downregulated. Network analysis, functional enrichment, annotation, and analysis of miRNA-protein interactions were also performed as part of the bioinformatics investigation of the discovered miRNAs and proteins revealing several pathways that lead to PD development and pathogenesis. Based on the analysis of miRNA and protein profiling, we have identified four miRNAs (hsa-miR-186-5p, miR-29b, miR-139 & has-miR-150-5p) and four proteins (YWHAZ, PSMA4, HYOU1, & SERPINA1), which can be targeted for the development of new biomarkers of PD. In vitro studies have identified the role of miR-186-5p in regulating the levels of the YWHAZ/YWHAB & CALM2 gene, which has shown maximum downregulation in PD patients and is known for its role in neuroprotection from apoptotic cell death & calcium regulation. In conclusion, our research has identified a group of miRNA-proteins that can be developed as PD biomarkers; however, future studies on the release of these miRNAs and proteins in extracellular vesicles circulating in the blood of PD patients can further validate these as specific biomarkers of PD.

Molecular basis of differential HLA class I-restricted T cell recognition of a highly networked HIV peptide.

Cytotoxic-T-lymphocyte (CTL) mediated control of HIV-1 is enhanced by targeting highly networked epitopes in complex with human-leukocyte-antigen-class-I (HLA-I). However, the extent to which the presenting HLA allele contributes to this process is unknown. Here we examine the CTL response to QW9, a highly networked epitope presented by the disease-protective HLA-B57 and disease-neutral HLA-B53. Despite robust targeting of QW9 in persons expressing either allele, T cell receptor (TCR) cross-recognition of the naturally occurring variant QW9_S3T is consistently reduced when presented by HLA-B53 but not by HLA-B57. Crystal structures show substantial conformational changes from QW9-HLA to QW9_S3T-HLA by both alleles. The TCR-QW9-B53 ternary complex structure manifests how the QW9-B53 can elicit effective CTLs and suggests sterically hindered cross-recognition by QW9_S3T-B53. We observe populations of cross-reactive TCRs for B57, but not B53 and also find greater peptide-HLA stability for B57 in comparison to B53. These data demonstrate differential impacts of HLAs on TCR cross-recognition and antigen presentation of a naturally arising variant, with important implications for vaccine design.

Chemically Fueled Autonomous Sol→Gel→Sol→Gel→Sol Transitions.

Complex non-equilibrium phase behaviors are a hallmark of natural self-assembling systems. Here we show how intricate phase transitions can be achieved through a chemically fueled reaction cycle to yield autonomous sol→gel→sol→gel→sol transitions. A relay of chemical transformations based on thiazinane metathesis leads to two consecutive transient gelations in a closed system. Within seconds of fuel addition to deactivated thiazinane monomers, an imine-based hydrogel forms that consists of fibrillar microspheres. This gel quickly loses its mechanical strength and forms a solution, from which a second aldehyde-based gel nucleates and remains stable for over one day. Overall, our reaction cycle gives rise to two consecutive re-entrant phase transitions without any experimental intervention.

A class-mismatched TCR bypasses MHC restriction via an unorthodox but fully functional binding geometry.

MHC restriction, which describes the binding of TCRs from CD4+ T cells to class II MHC proteins and TCRs from CD8+ T cells to class I MHC proteins, is a hallmark of immunology. Seemingly rare TCRs that break this paradigm exist, but mechanistic insight into their behavior is lacking. TIL1383I is a prototypical class-mismatched TCR, cloned from a CD4+ T cell but recognizing the tyrosinase tumor antigen presented by the class I MHC HLA-A2 in a fully functional manner. Here we find that TIL1383I binds this class I target with a highly atypical geometry. Despite unorthodox binding, TCR signaling, antigen specificity, and the ability to use CD8 are maintained. Structurally, a key feature of TIL1383I is an exceptionally long CDR3ß loop that mediates functions that are traditionally performed separately by hypervariable and germline loops in canonical TCR structures. Our findings thus expand the range of known TCR binding geometries compatible with normal function and specificity, provide insight into the determinants of MHC restriction, and may help guide TCR selection and engineering for immunotherapy.

High wall-plug efficiency and narrow linewidth III-V-on-silicon C-band DFB laser diodes.

We present recent results on compact and power efficient C-band distributed feedback lasers through adhesive bonding of a III-V die onto a silicon-on-insulator circuit. A wall-plug efficiency up to 16% is achieved for bias currents below 40 mA. The laser cavity is 180 µm long and a single facet output power up to 11 mW is measured at 20 °C by incorporating a broadband reflector in the silicon waveguide at one side of the cavity. Single mode operation at 1567 nm with a side mode suppression ratio of around 55 dB is demonstrated. By controlling the phase of the external feedback, the laser linewidth is decreased to 28 kHz. Measurement result shows a low relative intensity noise below -150 dB/Hz at 60 mA up to 6 GHz. We also report 20 and 10 Gbps data transmission at a bias current of 50 mA at 20 °C and 40 °C, respectively.