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1.
Artigo em Inglês | MEDLINE | ID: mdl-38575360

RESUMO

INTRODUCTION: Young newly married women and first-time parents (FTPs), particularly those living in slum settlements, have a high unmet need for modern contraceptive methods to limit and space births. We describe an intervention in which adolescents and youth sexual and reproductive health (AYSRH) services tailored to FTPs were incorporated into the government's existing family planning (FP) program in 5 cities of Uttar Pradesh. We examined the effect of this intervention on modern contraceptive use among FTPs aged 15-24 years. METHODS: To assess the effect of this pilot, in 2019, 1 year after the implementation of the program, we analyzed community-based output tracking survey data on 549 married women who are FTPs in the pilot cities. These FTPs were compared with 253 women who were FTPs from other cities where the program was implemented without a specific focus on FTPs. Descriptive statistics and multivariate logistic regression analysis were applied to understand the association between exposure to FP information, either through accredited social health activists or through service delivery points, and use of modern contraceptives. RESULTS: Use of modern contraceptives was higher among FTPs in the 5 pilot cities than non-pilot cities (39% vs. 32%; P<.05). The interaction effect of city type and exposure to the information showed a positive association between modern contraceptive use and program exposure, greater in pilot cities than non-pilot cities. CONCLUSIONS: Higher uptake of modern contraceptives among young women may be achieved when an FTP-focused intervention is layered on the government's existing FP programs. Future studies with a longer duration of implementation, in a wider geography, and with longitudinal design are recommended to provide more robust measures of high impact intervention/practices in urban areas.

2.
Biol Trace Elem Res ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38592566

RESUMO

Cadmium, a highly toxic heavy metal, can cause severe damage to several vital organs including the kidney, liver, and brain. Many of the natural compounds found in aromatic plants have beneficial pharmacological properties. Eugenol is one such compound reported to have anti-inflammatory and antioxidant properties. The aim of this study is to investigate whether eugenol, a natural compound found in aromatic plants known for its anti-inflammatory and antioxidant properties, can mitigate the detrimental effects of cadmium exposure on cardiac inflammation, oxidative stress, and dyslipidemia. Male albino rats were subjected to randomization into four groups, each comprising six animals, to investigate the potential of eugenol in mitigating cadmium-induced toxicity. All groups received oral gavage treatment for 21 days. Following the treatment regimen, cardiac tissue specimens were collected for analysis. The assessment of cardiac antioxidant status entailed the determination of enzymatic activities including catalase, SOD, GST, and GPx. Additionally, levels of lipid peroxidation, reduced glutathione, protein carbonyl oxidation, and thiol levels were quantified in the cardiac tissue samples. To evaluate cardiac damage, marker enzymes such as LDH and CK-MB were measured. Furthermore, the inflammatory response in the cardiac tissue induced by cadmium exposure was assessed through the quantification of NO, TNF-α, and IL-6 levels. Additionally, molecular docking and dynamics studies were conducted utilizing autodock and GLIDE methodologies. Cadmium administration markedly enhanced the activities of LDH and CK-MB, prominent cardiac markers. Furthermore, cadmium treatment also demonstrated a significant decrease in the reduced glutathione levels and antioxidant enzyme activities. Significant elevation of the inflammatory markers was also observed in the cadmium-treated group. Eugenol treatment effectively ameliorates cadmium-induced biochemical changes. This study underscores the potent anti-inflammatory and antioxidant attributes of eugenol. Co-administration of eugenol alongside cadmium exhibited remarkable protective efficacy against cadmium-induced cardio-toxicity. Eugenol demonstrated the capability to reinstate the cellular redox equilibrium of rats subjected to cadmium treatment to levels akin to those of the normal control group.

3.
Dev Cell ; 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38579720

RESUMO

The blueprint of the mammalian body plan is laid out during gastrulation, when a trilaminar embryo is formed. This process entails a burst of proliferation, the ingression of embryonic epiblast cells at the primitive streak, and their priming toward primitive streak fates. How these different events are coordinated remains unknown. Here, we developed and characterized a 3D culture of self-renewing mouse embryonic cells that captures the main transcriptional and architectural features of the early gastrulating mouse epiblast. Using this system in combination with microfabrication and in vivo experiments, we found that proliferation-induced crowding triggers delamination of cells that express high levels of the apical polarity protein aPKC. Upon delamination, cells become more sensitive to Wnt signaling and upregulate the expression of primitive streak markers such as Brachyury. This mechanistic coupling between ingression and differentiation ensures that the right cell types become specified at the right place during embryonic development.

4.
iScience ; 27(4): 109549, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38623328

RESUMO

Independently run single microgrids (MGs) encounter difficulties with inadequate self-consumption of local renewable energy and frequent power exchange with the grid. Combining numerous MGs to form a multi-microgrid (MMG) is a viable approach to enhance smart distribution networks' operational and financial performance. However, the correlation and coordination of intermittent power generation within each MG network pose many techno-economic challenges for energy sharing and trading. This review offers a comprehensive analysis of these challenges within the framework of MMG operations. It examines state-of-the-art methodologies for optimizing multi-energy dispatch and scrutinizes contemporary strategies within energy markets that contribute to the resilience of power systems. The discourse extends to the burgeoning role of blockchain technology in revolutionizing decentralized market frameworks and the intricacies of MMG coordination for reliable and cost-effective energy distribution. Overall, this study provides ample inspiration for theoretical and practical research to the new entrants and experts alike to develop new concepts for energy markets, scheduling and novel operating models for future resilient multi-energy networked systems/MMGs.

5.
Am J Hum Genet ; 111(4): 729-741, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38579670

RESUMO

Glutamine synthetase (GS), encoded by GLUL, catalyzes the conversion of glutamate to glutamine. GS is pivotal for the generation of the neurotransmitters glutamate and gamma-aminobutyric acid and is the primary mechanism of ammonia detoxification in the brain. GS levels are regulated post-translationally by an N-terminal degron that enables the ubiquitin-mediated degradation of GS in a glutamine-induced manner. GS deficiency in humans is known to lead to neurological defects and death in infancy, yet how dysregulation of the degron-mediated control of GS levels might affect neurodevelopment is unknown. We ascertained nine individuals with severe developmental delay, seizures, and white matter abnormalities but normal plasma and cerebrospinal fluid biochemistry with de novo variants in GLUL. Seven out of nine were start-loss variants and two out of nine disrupted 5' UTR splicing resulting in splice exclusion of the initiation codon. Using transfection-based expression systems and mass spectrometry, these variants were shown to lead to translation initiation of GS from methionine 18, downstream of the N-terminal degron motif, resulting in a protein that is stable and enzymatically competent but insensitive to negative feedback by glutamine. Analysis of human single-cell transcriptomes demonstrated that GLUL is widely expressed in neuro- and glial-progenitor cells and mature astrocytes but not in post-mitotic neurons. One individual with a start-loss GLUL variant demonstrated periventricular nodular heterotopia, a neuronal migration disorder, yet overexpression of stabilized GS in mice using in utero electroporation demonstrated no migratory deficits. These findings underline the importance of tight regulation of glutamine metabolism during neurodevelopment in humans.


Assuntos
Epilepsia Generalizada , Glutamato-Amônia Ligase , Glutamina , Animais , Humanos , Camundongos , Encéfalo/metabolismo , Epilepsia Generalizada/genética , Glutamato-Amônia Ligase/genética , Glutamato-Amônia Ligase/metabolismo , Glutamatos/metabolismo , Glutamina/genética , Glutamina/metabolismo
7.
Chemphyschem ; : e202400283, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38634178

RESUMO

Halocarbons have important industrial applications, however they contribute to global warming and the fact that they can cause ozone depletion. Hence, the techniques that can capture and recover the used halocarbons with energy efficiency methods have recently received greater attention. In this contribution, we report the capture of dichlorodifluoromethane (R12), which has high global warming and ozone depletion potential, using covalent organic polymers (COPs). The defect-engineered COPs were synthesized and demonstrated outstanding sorption capacities, ~226 wt% of R12 combined with linear-shaped adsorption isotherms. We further identified the plausible microscopic adsorption mechanism of the investigated COPs via grand canonical Monte Carlo simulations applied to non-defective and a collection of atomistic models of the defective COPs. The modeling work suggests that significant R12 adsorption is attributed to a gradual increment of porosities due to isolated/interconnected micro-/meso-pore channels and the change of the long-range ordering of both COPs. The successive hierarchical-pore-filling mechanism promotes R12 molecular adsorption via moderate van der Waals adsorbate-adsorbent interactions in the micropores of both COPs at low pressure followed by adsorbate-adsorbate interactions in the extra-voids created at moderate to high pressure ranges. This continuous pore-filling mechanism makes defective COPs as promising sorbents for halocarbon adsorption.

8.
J Orthod Sci ; 13: 9, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38516113

RESUMO

BACKGROUND: To evaluate and compare the distribution of stress and displacement of teeth during mandibular arch distalization using buccal shelf screws. MATERIALS AND METHODS: Three three-dimensional finite element models of mandibular arch were constructed with third molars extracted. Models 1, 2, and 3 were constructed on the basis of the lever arm heights of 0 mm, 3 mm, and 6 mm, respectively, between the lateral incisor and canine. A buccal shelf screw was placed at the area in the second molar region with the initial point of insertion being inter-dental between the first and second molars and 2 mm below the mucogingival junction. MBT pre-adjusted brackets (slot size 0.022 × 0.028") were placed over the clinical crown's center with a 0.019 × 0.025" stainless-steel archwire on three models. A retraction force of 300 g was applied with buccal shelf screws and a lever arm bilaterally using nickel-titanium closed coil springs. The displacement of each tooth was calculated on X, Y, and Z axes, and the von Mises stress distribution was visualized using color-coded scales using ANSYS 12.1 software. RESULT: The maximum von Mises stress in the cortical and cancellous bones was observed in model 1. The maximum von Mises stress in the buccal shelf screw and the cortical bone decreased as the height of the lever arm increased. Applying orthodontic forces at the level of 6 mm lever arm height resulted in greater biomechanical bodily movement in distalization of the mandibular molars compared to when the orthodontic forces were applied at the level of 0 mm lever arm height. CONCLUSION: Displacement of the entire arch may be dictated by a direct relationship between the center of resistance of the whole arch and the line of action generated between the buccal shelf screw and force application points at the archwire, which makes the total arch movement highly predictable.

9.
Nutrients ; 16(6)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38542811

RESUMO

This paper explores the multifaceted nature of ß-glucan, a notable dietary fiber (DF) with extensive applications. Beginning with an in-depth examination of its intricate polysaccharide structure, the discussion extends to diverse sources like oats, barley, mushrooms, and yeast, emphasizing their unique compositions. The absorption and metabolism of ß-glucan in the human body are scrutinized, emphasizing its potential health benefits. Extraction and purification processes for high-quality ß-glucan in food, pharmaceuticals, and cosmetics are outlined. The paper underscores ß-glucan's biofunctional roles in immune modulation, cholesterol regulation, and gastrointestinal health, supported by clinical studies. The review discusses global trade dynamics by tracing its evolution from a niche ingredient to a global commodity. In summary, it offers a comprehensive scientific perspective on ß-glucan, serving as a valuable resource for researchers, professionals, and industries exploring its potential in the dietary fiber landscape.


Assuntos
beta-Glucanas , Humanos , beta-Glucanas/química , Disponibilidade Biológica , Fibras na Dieta , Colesterol , Saccharomyces cerevisiae , Avena/química
10.
Environ Res ; 252(Pt 1): 118786, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38537743

RESUMO

Industrial wastewater contains a wide range of pollutants that, if released directly into natural ecosystems, have the potential to pose serious risks to the environment.This study aims to investigate sustainable and efficient approaches for treating tannery wastewater, employing a combination of hyphenated Fenton oxidation and adsorption processes. Rigorous analyses were conducted on wastewater samples, evaluating parameters like COD, sulphide, NH3-N, PO43-, NO3-, and Cr(VI). The performance of this adsorbent material was gauged through column adsorption experiments. A comprehensive characterization of the adsorbent was undertaken using techniques such as SEM, EDX, BET, FTIR, XRD, and LIBS. The study delved into varying operational parameters like bed depth (ranging from 3.5 to 9.5 cm) diameter (2.5 cm) and influent flow rate (ranging from 5 to 15mLmin-1). The experimental outcomes revealed that increasing the bed depth and decreasing the influent flow rate significantly bolstered the adsorption column's effectiveness. Breakthrough curves obtained were fitted with different models, including the Thomas and Yoon-Nelson models. The most optimal column performance was achieved with a bed height of 10.5 cm and a flow rate of 5mLmin-1. The combined process achieved removal efficiencies of 94.5% for COD, 97.4% for sulphide, 96.2% for NH3-N, 83.1% for NO3-, 79.3% for PO43-, and 96.9% for Cr(VI) in tannery effluent. This research presents a notable stride toward the development of sustainable and efficient strategies for tannery wastewater treatment.

11.
Indian J Community Med ; 49(1): 218-222, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38425981

RESUMO

Introduction: Family adoption program (FAP) incorporated into the undergraduate medical education curriculum is beneficial to all stakeholders involved. Many medical colleges have started FAP at different times and various levels based on resources availability, feasibility, and accessibility. This article is intended to cover the process of FAP implementation, the strength, weakness, opportunities, and challenges at various levels, and its scope in future. Methodology: FAP was launched by adopting a hamlet 17 km away from the college. During the foundation course, orientation lessons and logbook discussions were conducted online before the actual field visit. During the initial visit, families were assigned, which was followed by collecting sociodemographic information, a plantation drive, and organizing medical camp/ door to door screening in the last visits for phase one students. Observations: The strengths perceived were early community exposure of students and leadership skills, and the weaknesses were allocating adequate number of slots in the curriculum, adopting families far away, etc., Similarly, FAP has an opportunity to achieve the larger goal of Heath for All in terms of identifying, following up, and managing various socio clinical cases in the adopted families. However, few challenges can pose as it progresses across other phases, such as language problem, allotment of problem families, existing social pathology in family, cultural taboos, etc. Conclusion: The article suggests that once a student leaves, another student should continue the cycle of adoption and provide continuum care of services to prevent the family from being orphaned.

12.
Front Immunol ; 15: 1202017, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38545119

RESUMO

Engineered T cell-based adoptive immunotherapies met promising success for the treatment of hematological malignancies. Nevertheless, major hurdles remain to be overcome regarding the management of relapses and the translation to solid tumor settings. Properties of T cell-based final product should be appropriately controlled to fine-tune the analysis of clinical trial results, to draw relevant conclusions, and finally to improve the efficacy of these immunotherapies. For this purpose, we addressed the existence of atypical T cell subsets and deciphered their phenotypic and functional features in an HPV16-E7 specific and MHC II-restricted transgenic-TCR-engineered T cell setting. To note, atypical T cell subsets include mismatched MHC/co-receptor CD8 or CD4 and miscommitted CD8+ or CD4+ T cells. We generated both mismatched and appropriately matched MHC II-restricted transgenic TCR on CD8 and CD4-expressing T cells, respectively. We established that CD4+ cultured T cells exhibited miscommitted phenotypic cytotoxic pattern and that both interleukin (IL)-2 or IL-7/IL-15 supplementation allowed for the development of this cytotoxic phenotype. Both CD4+ and CD8+ T cell subsets, transduced with HPV16-E7 specific transgenic TCR, demonstrated cytotoxic features after exposure to HPV-16 E7-derived antigen. Ultimately, the presence of such atypical T cells, either mismatched MHC II-restricted TCR/CD8+ T cells or cytotoxic CD4+ T cells, is likely to influence the fate of patient-infused T cell product and would need further investigation.


Assuntos
Imunoterapia Adotiva , Recidiva Local de Neoplasia , Humanos , Linfócitos T CD4-Positivos , Receptores de Antígenos de Linfócitos T/genética , Subpopulações de Linfócitos T
13.
ACS Sustain Chem Eng ; 12(8): 3243-3255, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38425833

RESUMO

Plastics' long degradation time and their role in adding millions of metric tons of plastic waste to our oceans annually present an acute environmental challenge. Handling end-of-life waste from wind turbine blades (WTBs) is equally pressing. Currently, WTB waste often finds its way into landfills, emphasizing the need for recycling and sustainable solutions. Mechanical recycling of composite WTB presents an avenue for the recovery of glass fibers (GF) for repurposing as fillers or reinforcements. The resulting composite materials exhibit improved properties compared to the pure PAN polymer. Through the employment of the dry-jet wet spinning technique, we have successfully manufactured PAN/GF coaxial-layered fibers with a 0.1 wt % GF content in the middle layer. These fibers demonstrate enhanced mechanical properties and a lightweight nature. Most notably, the composite fiber demonstrates a significant 24.4% increase in strength and a 17.7% increase in modulus. These fibers hold vast potential for various industrial applications, particularly in the production of structural components (e.g., electric vehicles), contributing to enhanced performance and energy efficiency.

14.
Indian J Community Med ; 49(1): 175-180, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38425959

RESUMO

Background: Lack of interest has been cited by many studies as the predominant cause for students undervaluing the subject of Community Medicine. However, there are few valid and reliable tools that could measure this interest. To develop and validate a questionnaire to measure a medical student's interest in the subject of Community Medicine. Material and Methods: Cross-sectional study conducted at MTMC Jamshedpur. The Community Medicine Interest Questionnaire (CMIQ) was developed in two phases: item generation and item reduction. Items were generated through a review of the literature, focused group discussions, and in-depth interviews. In the item reduction phase, the content and construct validity of the questionnaire were ascertained. Content validity was carried out by a group of experts based on three parameters: the interrater agreement on the representativeness of the item, the interrater agreement on the clarity of the items, and the content validity index. The construct validity was ascertained through pilot testing of 480 responses from undergraduate medical students. Exploratory factor analysis through principal axis factoring and Promax rotation. Results: Twenty-five items were generated. Three of these items were removed following expert validation. Furthermore, three items were removed after pilot testing. The resulting CMIQ consisted of 19 items distributed over three dimensions: feeling, value, and predisposition to reengage toward the subject. The internal consistency of each of the subscales was ascertained. Conclusions: CMIQ is a valid and reliable tool that can be used to measure such interest for providing educational interventions.

16.
BMJ Case Rep ; 17(3)2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38442962

RESUMO

Breast cancer is a heterogeneous set of carcinomas comprising a subgroup of invasive ductal carcinomas and numerous infrequent subtypes. Primary squamous cell carcinoma (SCC) breast is sporadic, accounting for less than 0.1% of all invasive subtypes. Primary metastases to soft tissues of the oral cavity are incredibly rare, amounting to 0.1% of oral malignancies. Diagnosing metastasis to the oral cavity is an enigma to clinicians without pathognomonic signs and symptoms. Here, we report a case of SCC breast, who developed metastatic deposits in the left upper lip after a disease-free survival of 1 year. There are no reports of SCC breast metastasising to the oral cavity, and probably, this is the first such case getting reported. The survival of such patients is abysmal, with most cases surviving less than a year post diagnosis. While treating patients with a history of malignancy, a high degree of clinical presentiment is required.


Assuntos
Neoplasias da Mama , Carcinoma de Células Escamosas , Neoplasias Bucais , Humanos , Feminino , Lábio , Carcinoma de Células Escamosas/diagnóstico , Mama , Neoplasias Bucais/diagnóstico
17.
ACS Appl Mater Interfaces ; 16(8): 10565-10579, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38377563

RESUMO

Post-traumatic hemorrhage, which can result from accidents or battlefield injuries, is a significant global concern due to the high prehospital mortality rate. Substantial efforts have been made to develop hemostatic agents that can effectively reduce hemorrhage in the immediate aftermath of a traumatic event. The present study investigated the potential efficacy of Ca2+ and Zn2+ supplemented sodium alginate-based dry hemostatic particles (SA-CZ DHP) to manage excessive blood loss or post-traumatic hemorrhage. SA-CZ DHP were developed, followed by their physical and biochemical characterization, cytocompatibility and hemocompatibility testing, and critical evaluation of the hemostatic potential in vitro and in vivo. The safe SA-CZ DHP showed high absorption and accelerated blood clotting kinetics with reduced coagulation time (≈70%, p < 0.0001) in whole human blood, observed with insignificant hemolysis and uninterrupted RBC morphology. SA-CZ DHP significantly reduced the mean blood loss (≈90% in SD rats tail incision), and bleeding time (≈60% in BALB/c mice tail incision) was at par with commercially available Celox hemostatic granules. In conclusion, the biocompatible SA-CZ DHP exhibited rapid and effective management of excessive blood loss. It is also pertinent to note that the developed formulation could be a cost-effective alternative to its commercial counterparts.


Assuntos
Hemostáticos , Camundongos , Ratos , Humanos , Animais , Hemostáticos/farmacologia , Hemostáticos/uso terapêutico , Hemostáticos/química , Alginatos/uso terapêutico , Alginatos/farmacologia , Cálcio , Zinco/uso terapêutico , Zinco/farmacologia , Ratos Sprague-Dawley , Hemorragia/tratamento farmacológico , Hemostasia
18.
Int J Biol Macromol ; 263(Pt 1): 130238, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38367787

RESUMO

Acute lymphoblastic leukemia (ALL), a hematologic cancer that involves the production of abnormal lymphoid precursor cells, primarily affects children aged 2 to 10 years. The bacterial enzyme L-asparaginase produced from Escherichia coli is utilised as first-line therapy, despite the fact that 30 % of patients have a treatment-limiting hypersensitivity reaction. The current study elucidates the biosynthesis of extremely stable, water-dispersible, anisotropic silver nanoparticles (ANI Ag NPs) at room temperature and investigation of its anti-tumor potency in comparison to L-asparaginase. The optical, morphological, compositional, and structural properties of synthesized nanoparticles were evaluated using UV-Vis-NIR spectroscopy, Transmission Electron Microscopy (TEM), Fourier Transform Infrared Spectroscopy, and X-ray Diffractometer. The UV-Vis-NIR spectra revealed the typical Surface Plasmon Resonance (SPR) at 423 nm along with additional NIR absorption at 962 nm and 1153 nm, while TEM images show different shapes and sizes of Ag nanoparticles ranging from 6.81 nm to 46 nm, together confirming their anisotropic nature. Further, the MTT assay demonstrated promising anticancer effects of ANI Ag NPs with an IC50 value of ∼7 µg/mL against HuT-78 cells. These sustainable anisotropic silver nanoparticles exhibited approximately four times better cytotoxic ability (at and above 10 µg/mL concentrations) than L-asparaginase against HuT-78 cells (a human T lymphoma cell line). Apoptosis analysis by Wright-Geimsa, Annexin-V, and DAPI staining indicated the role of apoptosis in ANI Ag NPs-mediated cell death. The measurement of NO, and Bcl2 and cleaved caspase-3 levels by colorimetric method and immunoblotting, respectively suggested their involvement in ANI Ag NPs-elicited apoptosis. The findings indicate that the biogenic approach proposed herein holds tremendous promise for the rapid and straightforward design of novel multifunctional nanoparticles for the treatment of T cell malignancies.


Assuntos
Nanopartículas Metálicas , Neoplasias , Criança , Humanos , Prata/química , Asparaginase/farmacologia , Nanopartículas Metálicas/química , Neoplasias/patologia , Apoptose , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana
19.
bioRxiv ; 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38328095

RESUMO

It is widely believed that tissue mechanical properties, determined mainly by the extracellular matrix (ECM), are actively maintained. However, despite its broad importance to biology and medicine, tissue mechanical homeostasis is poorly understood. To explore this hypothesis, we developed mutations in the mechanosensitive protein talin1 that alter cellular sensing of ECM stiffness. Mutation of a novel mechanosensitive site between talin1 rod domain helix bundles 1 and 2 (R1 and R2) shifted cellular stiffness sensing curves, enabling cells to spread and exert tension on compliant substrates. Opening of the R1-R2 interface promotes binding of the ARP2/3 complex subunit ARPC5L, which mediates the altered stiffness sensing. Ascending aortas from mice bearing these mutations show increased compliance, less fibrillar collagen, and rupture at lower pressure. Together, these results demonstrate that cellular stiffness sensing regulates ECM mechanical properties. These data thus directly support the mechanical homeostasis hypothesis and identify a novel mechanosensitive interaction within talin that contributes to this mechanism.

20.
Adv Mater ; : e2309497, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38350050

RESUMO

Photonic diplexers are being widely investigated for high data transfer rates in on-chip communication. However, dividing the available spectrum into nonoverlapping multicarrier frequency sub-bands has remained a challenge in designing frequency-selective time-invariant channels. Here, an on-chip topological diplexer is reported exhibiting terahertz frequency band filtering through Klein tunneling of topological edge modes. The silicon topological diplexer chip facilitates two high-speed channels with quadrature amplitude modulation (QAM) over a broad bandwidth of 12.5 GHz each. These channels operate at carrier frequencies of 305 and 321.6 GHz, achieving a combined diplexer capacity of 150 Gbit s-1 . To ensure minimal interference between adjacent channels, a guard band is implemented. Topologically protected edge modes suppress the frequency selective fading of the broadband signals and hold promise for diverse integrated photonic applications spanning terahertz and telecommunication realms, including the design of lossless topological multiplexers, interconnects, antennas, and modulators for the sixth to X generation (6G to XG) wireless.

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