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1.
Front Oncol ; 14: 1430971, 2024.
Article de Anglais | MEDLINE | ID: mdl-39091922

RÉSUMÉ

Three main areas of research revolve around extracellular vesicles (EVs): their use as early detection diagnostics for cancer prevention, engineering of EVs or other enveloped viral-like particles for therapeutic purposes and to understand how EVs impact biological processes. When investigating the biology of EVs, it is important to consider strategies able to track and alter EVs directly in vivo, as they are released by donor cells. This can be achieved by suitable engineering of EV donor cells, either before implantation or directly in vivo. Here, we make a case for the study of native EVs, that is, EVs released by cells living within a tissue. Novel genetic approaches to detect intercellular communications mediated by native EVs and profile recipient cells are discussed. The use of Rab35 dominant negative mutant is proposed for functional in vivo studies on the roles of native EVs. Ultimately, investigations on native EVs will tremendously advance our understanding of EV biology and open novel opportunities for therapy and prevention.

2.
Nat Prod Res ; : 1-8, 2024 Aug 02.
Article de Anglais | MEDLINE | ID: mdl-39093996

RÉSUMÉ

Current study aimed to disclose the anti-inflammatory potential of the methanolic leaf extracts of L. wightiana (LWME). The in vitro studies focused on enzyme inhibition assays targeting the key enzymes such as cyclooxygenase, lipoxygenase and nitric oxide synthase and revealed that LWME effectively inhibited the activity of these enzymes. Gene expression studies confirmed the anti-inflammatory effect, demonstrating down regulation of genes associated with inflammation and key proinflammatory factors such as COX-2, TNF-α, IL-6 and NFkB. In vivo anti-inflammatory experiments by carrageenan-induced paw edoema method in model animals and inflammation was found to be reduced by 10% concentration of extract and significant at P˂0.001 level. GCMS and LCMS analysis were conducted and the resulted compounds were docked against target proteins indicated that most of the bioactive compounds showed better binding affinity with enzymes in which the dicentrinone showed higher affinity and it may be useful in the treatment of several ailments.

3.
EBioMedicine ; 106: 105266, 2024 Aug 01.
Article de Anglais | MEDLINE | ID: mdl-39094262

RÉSUMÉ

The Chimeric Antigen Receptor (CAR) T cell therapy has emerged as a ground-breaking immunotherapeutic approach in cancer treatment. To overcome the complexity and high manufacturing cost associated with current ex vivo CAR T cell therapy products, alternative strategies to produce CAR T cells directly in the body have been developed in recent years. These strategies involve the direct infusion of CAR genes via engineered nanocarriers or viral vectors to generate CAR T cells in situ. This review offers a comprehensive overview of recent advancements in the development of T cell-targeted CAR generation in situ. Additionally, it identifies the challenges associated with in vivo CAR T method and potential strategies to overcome these issues.

4.
Drug Metab Dispos ; 2024 Aug 02.
Article de Anglais | MEDLINE | ID: mdl-39095207

RÉSUMÉ

Hepatic clearance (CLH) prediction is a critical parameter to estimate human dose. However, CLH underpredictions are common, especially for slowly metabolized drugs, and may be attributable to drug properties that pose challenges for conventional in vitro ADME assays, resulting in non-valid data, which prevents in-vitro-to-in-vivo extrapolation and CLH predictions. Other processes, including hepatocyte and biliary distribution via transporters, can also play significant roles in CLH Recent advances in understanding the interplay of metabolism and drug transport for clearance processes have aided in developing the Extended Clearance Model (ECM). In this study, we demonstrate proof-of-concept of a novel two-step assay enabling measurement of multiple kinetic parameters from a single experiment in plated human primary hepatocytes with and without transporter and CYP inhibitors - the Hepatocyte Uptake and Loss Assay (HUpLA). HUpLA accurately predicted the CLH of 8 of the 9 drugs (within 2-fold of the observed CLH). Distribution clearances were within 3-fold of observed literature values in standard uptake and efflux assays. In comparison, the conventional suspension hepatocyte stability assay poorly predicted the CLH CLH of only 2 drugs were predicted within 2-fold of the observed CLH Therefore, HUpLA is advantageous by enabling the measurement of enzymatic and transport processes concurrently within the same system, alleviating the need for applying scaling factors independently. The use of primary human hepatocytes enables physiologically relevant exploration of transporter-enzyme interplay. Most importantly, HUpLA shows promise as a sensitive measure for low-turnover drugs. Further evaluation across different drug characteristics is needed to demonstrate method robustness. Significance Statement HUpLA involves measuring four commonly derived in vitro hepatic clearance endpoints. Since endpoints are generated within a single test system, it blunts experimental error originating from assays otherwise conducted independently. A key advance is the concept of removing drug-containing media following intracellular drug loading, enabling measurement of drug reappearance rate in media, as well as measurement of loss of total drug in the test system unencumbered by background quantities of drug in media otherwise present in a conventional assay.

5.
Article de Anglais | MEDLINE | ID: mdl-39094607

RÉSUMÉ

Magnetic Resonance Imaging (MRI) employs a radiofrequency electromagnetic field to create pictures on a computer. The consequences of radiofrequency (RF) absorption include the heating of the tissue and the patient's capacity to remove excess heat. The prospective biological consequences of exposure to radiofrequency electromagnetic fields (RF EMFs) have not yet been demonstrated, and there is not enough evidence on biological hazards to offer a definite response concerning possible RF health dangers. Therefore, it is crucial to research the health concerns in reaction to RF EMFs, considering the entire exposure in terms of patients receiving MRI. Monitoring increases in temperature in-vivo throughout MRI is extremely invasive and has resulted in a rise in the utilization of computational methods to estimate distributions of temperatures. The purpose of this study is to estimate the absorbed power of the brain exposed to RF in patients undergoing brain MRI. A three-dimensional Penne's bio-heat equation was modified to computationally analyze the effects of RF radiation at frequencies exceeding 100 kHz exposures on the brain. The instantaneous temperature distributions of the in-vivo tissue in the brain temperatures measured at a time, t = 20.62 seconds is 0.2 °C and t = 30.92 seconds is 0.4 °C, while the highest temperatures recorded at 1.03 minutes and 2.06 minutes were 0.4 °C and 0.6 °C accordingly. From the temperature distributions of the in-vivo tissue in the brain temperatures measured, there is heat build-up in patients who are exposed to electromagnetic frequency ranges, and, consequently, temperature increases within patients are difficult to prevent. The study has, however, indicated that lengthier imaging duration appears to be related to increasing body temperature. .

6.
Regul Toxicol Pharmacol ; : 105682, 2024 Jul 31.
Article de Anglais | MEDLINE | ID: mdl-39094967

RÉSUMÉ

Regulatory guidance for global drug development relies on animal studies to evaluate safety risks for humans, including risk of reproductive toxicity. Weight-of-evidence approaches (WoE) are increasingly becoming acceptable to evaluate risk. A WoE for developmental risk of monoclonal antibodies (mAbs) was evaluated for its ability to retrospectively characterize risk and to determine the need for further in vivo testing based on the remaining uncertainty. Reproductive toxicity studies of 65 mAbs were reviewed and compared to the WoE. Developmental toxicities were absent in 52/65 (80%) mAbs. Lack of toxicity was correctly predicted in 29/52 (56%) cases. False positive and equivocal predictions were made in 9/52 (17%) and 14/52 (27%) cases. For 3/65 (5%) mAbs, the findings were equivocal. Of mAbs with developmental toxicity findings (10/65, 15%), the WoE correctly anticipated pharmacology based reproductive toxicity without any false negative predictions in 9/10 (90%) cases, and in the remaining case ( 1/10, 10%) an in vivo study was recommended due to equivocal WoE outcome. Therefore, this WoE approach could characterize presence and absence of developmental risk without animal studies. The current WoE could have reduced the need for developmental toxicity studies by 42% without loss of important patient information in the label.

7.
Sci Rep ; 14(1): 18248, 2024 Aug 06.
Article de Anglais | MEDLINE | ID: mdl-39107444

RÉSUMÉ

Wear of the ultra-high molecular-weight polyethylene (UHMWPE) component in total knee arthroplasty contributes to implant failure. It is often detected late, when patients experience pain or instability. Early monitoring could enable timely intervention, preventing implant failure and joint degeneration. This study investigates the accuracy and precision (repeatability) of model-based wear measurement (MBWM), a novel technique that can estimate inlay thickness and wear radiographically. Six inlays were milled from non-crosslinked UHMWPE and imaged via X-ray in anteroposterior view at flexion angles 0°, 30°, and 60° on a phantom knee model. MBWM measurements were compared with reference values from a coordinate measurement machine. Three inlays were subjected to accelerated wear generation and similarly evaluated. MBWM estimated inlay thickness with medial and lateral accuracies of 0.13 ± 0.09 and 0.14 ± 0.09 mm, respectively, and linear wear with an accuracy of 0.07 ± 0.06 mm. Thickness measurements revealed significant lateral differences at 0° and 30° (0.22 ± 0.08 mm vs. 0.06 ± 0.06 mm, respectively; t-test, p = 0.0002). Precision was high, with average medial and lateral differences of - 0.01 ± 0.04 mm between double experiments. MBWM using plain radiographs presents a practical and promising approach for the clinical detection of implant wear.


Sujet(s)
Arthroplastie prothétique de genou , Prothèse de genou , Défaillance de prothèse , Arthroplastie prothétique de genou/méthodes , Humains , Polyéthylènes , Radiographie/méthodes , Articulation du genou/imagerie diagnostique , Articulation du genou/chirurgie , Test de matériaux/méthodes
8.
Microb Cell Fact ; 23(1): 219, 2024 Aug 06.
Article de Anglais | MEDLINE | ID: mdl-39103877

RÉSUMÉ

BACKGROUND: Xanthenes and multi-aryl carbon core containing compounds represent different types of complex and condensed architectures that have impressive wide range of pharmacological, industrial and synthetic applications. Moreover, indoles as building blocks were only found in naturally occurring metabolites with di-aryl carbon cores and in chemically synthesized tri-aryl carbon core containing compounds. Up to date, rare xanthenes with indole bearing multicaryl carbon core have been reported in natural or synthetic products. The underlying mechanism of fluorescein-like arthrocolins with tetra-arylmethyl core were synthesized in an engineered Escherichia coli fed with toluquinol remained unclear. RESULTS: In this study, the Keio collection of single gene knockout strains of 3901 mutants of E. coli BW25113, together with 14 distinct E. coli strains, was applied to explore the origins of endogenous building blocks and the biogenesis for arthrocolin assemblage. Deficiency in bacterial respiratory and aromatic compound degradation genes ubiX, cydB, sucA and ssuE inhibited the mutant growth fed with toluquinol. Metabolomics of the cultures of 3897 mutants revealed that only disruption of tnaA involving in transforming tryptophan to indole, resulted in absence of arthrocolins. Further media optimization, thermal cell killing and cell free analysis indicated that a non-enzyme reaction was involved in the arthrocolin biosynthesis in E. coli. Evaluation of redox potentials and free radicals suggested that an oxygen-mediated free radical reaction was responsible for arthrocolins formation in E. coli. Regulation of oxygen combined with distinct phenol derivatives as inducer, 31 arylmethyl core containing metabolites including 13 new and 8 biological active, were isolated and characterized. Among them, novel arthrocolins with p-hydroxylbenzene ring from tyrosine were achieved through large scale of aerobic fermentation and elucidated x-ray diffraction analysis. Moreover, most of the known compounds in this study were for the first time synthesized in a microbe instead of chemical synthesis. Through feeding the rat with toluquinol after colonizing the intestines of rat with E. coli, arthrocolins also appeared in the rat blood. CONCLUSION: Our findings provide a mechanistic insight into in vivo synthesis of complex and condensed arthrocolins induced by simple phenols and exploits a quinol based method to generate endogenous aromatic building blocks, as well as a methylidene unit, for the bacteria-facilitated synthesis of multiarylmethanes.


Sujet(s)
Escherichia coli , Oxygène , Phénols , Escherichia coli/métabolisme , Escherichia coli/effets des médicaments et des substances chimiques , Escherichia coli/génétique , Phénols/métabolisme , Oxygène/métabolisme , Radicaux libres/métabolisme , Méthane/métabolisme , Animaux , Rats , Indoles/métabolisme
9.
Hippocampus ; 2024 Aug 06.
Article de Anglais | MEDLINE | ID: mdl-39105449

RÉSUMÉ

The hippocampus is considered essential for several forms of declarative memory, including spatial and social memory. Despite the extensive research of the classic subfields of the hippocampus, the fasciola cinerea (FC)-a medially located structure within the hippocampal formation-has remained largely unexplored. In the present study, we performed a morpho-functional characterization of principal neurons in the mouse FC. Using in vivo juxtacellular recording of single neurons, we found that FC neurons are distinct from neighboring CA1 pyramidal cells, both morphologically and electrophysiologically. Specifically, FC neurons displayed non-pyramidal morphology and granule cell-like apical dendrites. Compared to neighboring CA1 pyramidal neurons, FC neurons exhibited more regular in vivo firing patterns and a lower tendency to fire spikes at short interspike intervals. Furthermore, tracing experiments revealed that the FC receives inputs from the lateral but not the medial entorhinal cortex and CA3, and it provides a major intra-hippocampal projection to the septal CA2 and sparser inputs to the distal CA1. Overall, our results indicate that the FC is a morphologically and electrophysiologically distinct subfield of the hippocampal formation; given the established role of CA2 in social memory and seizure initiation, the unique efferent intra-hippocampal connectivity of the FC points to possible roles in social cognition and temporal lobe epilepsy.

10.
Daru ; 2024 Aug 06.
Article de Anglais | MEDLINE | ID: mdl-39106020

RÉSUMÉ

BACKGROUND: Multiple Sclerosis (MS) is a chronic autoimmune, inflammatory neurological disease of the CNS. Riluzole and dimethyl fumarate (DMF) are two FDA-approved drugs to treat amyotrophic lateral sclerosis (ALS) and MS. Riluzole (a benzothiazole derivative) inhibits glutamate release from nerve terminals by antagonizing the N-Methyl-D-Aspartate (NMDA) receptor, and DMF upregulates anti-oxidative pathways. OBJECTIVES: Herein, using molecular hybridization strategy, we synthesized some new hybrid structures of Riluzole and DMF through some common successive synthetic pathways for evaluating their potential activity for remyelination in MS treatment. METHODS: Molecular docking experiments assessed the binding affinity of proposed structures to the NMDA active site. The designed structures were synthesized and purified based on well-known chemical synthesis procedures. Afterward, in vivo evaluation for their activity was done in the C57Bl/6 Cuprizone-induced demyelination MS model. RESULTS AND CONCLUSION: The proposed derivatives were recognized to be potent enough based on docking studies (ΔGbind of all derivatives were -7.2 to -7.52 compare to the Ifenprodil (-6.98) and Riluzole (-4.42)). The correct structures of desired derivatives were confirmed using spectroscopic methods. Based on in vivo studies, D4 and D6 derivatives exhibited the best pharmacological results, although only D6 showed a statistically significant difference compared to the control. Also, for D4 and D6 derivatives, myelin staining confirmed reduced degeneration in the corpus callosum. Consequently, D4 and D6 derivatives are promising candidates for developing new NMDA antagonists with therapeutic value against MS disorders.

11.
Front Immunol ; 15: 1442160, 2024.
Article de Anglais | MEDLINE | ID: mdl-39100673

RÉSUMÉ

The COVID-19 pandemic has uncovered the high genetic variability of the SARS-CoV-2 virus and its ability to evade the immune responses that were induced by earlier viral variants. Only a few monoclonal antibodies that have been reported to date are capable of neutralizing a broad spectrum of SARS-CoV-2 variants. Here, we report the isolation of a new broadly neutralizing human monoclonal antibody, iC1. The antibody was identified through sorting the SARS-CoV-1 RBD-stained individual B cells that were isolated from the blood of a vaccinated donor following a breakthrough infection. In vitro, iC1 potently neutralizes pseudoviruses expressing a wide range of SARS-CoV-2 Spike variants, including those of the XBB sublineage. In an hACE2-transgenic mouse model, iC1 provided effective protection against the Wuhan strain of the virus as well as the BA.5 and XBB.1.5 variants. Therefore, iC1 can be considered as a potential component of the broadly neutralizing antibody cocktails resisting the SARS-CoV-2 mutation escape.


Sujet(s)
Angiotensin-converting enzyme 2 , Anticorps monoclonaux , Anticorps neutralisants , Anticorps antiviraux , COVID-19 , Souris transgéniques , SARS-CoV-2 , Animaux , SARS-CoV-2/immunologie , Humains , COVID-19/immunologie , COVID-19/prévention et contrôle , COVID-19/virologie , Angiotensin-converting enzyme 2/immunologie , Angiotensin-converting enzyme 2/génétique , Angiotensin-converting enzyme 2/métabolisme , Souris , Anticorps antiviraux/immunologie , Anticorps monoclonaux/immunologie , Anticorps neutralisants/immunologie , Glycoprotéine de spicule des coronavirus/immunologie , Glycoprotéine de spicule des coronavirus/génétique , Pandémies/prévention et contrôle , Betacoronavirus/immunologie , Betacoronavirus/génétique , Anticorps neutralisants à large spectre/immunologie , Modèles animaux de maladie humaine , Pneumopathie virale/immunologie , Pneumopathie virale/virologie , Pneumopathie virale/prévention et contrôle , Infections à coronavirus/immunologie , Infections à coronavirus/virologie , Infections à coronavirus/prévention et contrôle
12.
J Ethnopharmacol ; : 118671, 2024 Aug 03.
Article de Anglais | MEDLINE | ID: mdl-39103024

RÉSUMÉ

ETHNOPHARMACOLOGICAL RELEVANCE: Rheumatoid arthritis (RA) is a multifactorial, polygenic inflammatory disease. Mesua assamica (King & Prain) Kosterm. (MA) is an endangered medicinal plant indigenous to South Asia, primarily to Assam in India. The tree bark is claimed to possess anti-inflammatory, anti-diabetic, anti-cancer, and anti-malarial properties; nevertheless, its role in RA has not been elucidated. Hence, this study aims to investigate the in-vitro and in-vivo anti-arthritic effects of Mesua assamica bark ethanolic extract (MAE). AIM OF THE STUDY: This study aims to investigate the anti-rheumatic potential of MAE in-vitro on RAW 264.7 cells for its anti-oxidant and anti-inflammatory activities and in-vivo on the CFA-induced adjuvant arthritis in the rat model. MATERIALS AND METHODS: We investigated the possible therapeutic effects of MAE in-vitro using RAW 264.7 cells triggered by LPS. Meanwhile, adult Wistar rats were injected intradermally with 100 µl of CFA to induce arthritis, and they were given MAE orally at doses of 100 and 200 mg/kg for up to 28 days. Paw volume analysis, X-ray radiography, anti-oxidant levels analysis, gene and protein expression studies, and histological analysis were carried out to assess the effects of MAE in-vivo. RESULTS: MAE significantly mitigated the inflammation by reducing ROS levels and dropped the nitrite, PGE2, and COX-2 levels enhanced by LPS in-vitro. At the same time, MAE treatment reduced the paw and joint inflammation and increased the immune organ index in the CFA rats. Histopathology data revealed that MAE mitigated the CFA-induced lesions of the ankle joints and synovial tissues. Similarly, MAE significantly abated the secretion of pro-inflammatory cytokines, inhibited the protein expression of TLR4, NF-кB, COX-2, and iNOS, as well as improved the Nrf2 and HO-1 levels in-vitro and in-vivo. CONCLUSION: All the results highlighted the anti-rheumatic potential of MAE in RA in-vitro and in-vivo by inhibiting the TLR4/NF-кB/COX-2/iNOS and promoting the Nrf2/HO-1 signaling axis.

13.
Curr Opin Chem Biol ; 81: 102508, 2024 Aug 03.
Article de Anglais | MEDLINE | ID: mdl-39098211

RÉSUMÉ

Embedding a catalytically competent transition metal into a protein scaffold affords an artificial metalloenzyme (ArM). Such hybrid catalysts display features that are reminiscent of both homogeneous and enzymatic catalysts. Pioneered by Whitesides and Kaiser in the late 1970s, this field of ArMs has expanded over the past two decades, marked by ever-increasing diversity in reaction types, cofactors, and protein scaffolds. Recent noteworthy developments include i) the use of earth-abundant metal cofactors, ii) concurrent cascade reactions, iii) synergistic catalysis, and iv) in vivo catalysis. Thanks to significant progress in computational protein design, ArMs based on de novo-designed proteins and tailored chimeric proteins promise a bright future for this exciting field.

14.
Ocul Surf ; 2024 Aug 02.
Article de Anglais | MEDLINE | ID: mdl-39098764

RÉSUMÉ

PURPOSE: To evaluate and compare subbasal corneal nerve parameters of the inferior whorl in patients with dry eye disease (DED), neuropathic corneal pain (NCP), and controls using a novel deep-learning-based algorithm to analyze in-vivo confocal microscopy (IVCM) images. METHODS: Subbasal nerve plexus (SNP) images of the inferior whorl of patients with DED (n=49, 77 eyes), NCP (n=14, 24 eyes), and controls (n=41, 59 eyes) were taken with IVCM and further analyzed using an open-source artificial intelligence (AI)-based algorithm previously developed by our group. This algorithm automatically segments nerves, immune cells, and neuromas in the SNP. The following parameters were compared between groups: nerve area density, average nerve thickness, average nerve segment tortuosity, junction point density, neuroma density, and immune cell density. RESULTS: 160 eyes of 104 patients (63% females), aged 56.8+15.4 years, were included. The mean nerve area density was significantly lower in the DED (P=0.012) and NCP (P<0.001) groups compared to the control group. The junction point density was lower in the NCP group (P=0.001) compared to the control group and DED group (P=0.004). The immune cell density was higher in the DED group compared with controls (P<0.001). CONCLUSIONS: Deep-learning-based analysis of IVCM images of the corneal SNP inferior whorl distinguished a decreased mean nerve area density in patients with DED and NCP compared with controls and an increased immune cell density in patients with oGVHD- and SS-associated DED. These findings suggest that the inferior whorl could be used as landmark to distinguish between patients with DED and NCP.

15.
bioRxiv ; 2024 Jul 24.
Article de Anglais | MEDLINE | ID: mdl-39091725

RÉSUMÉ

The experimental challenges posed by integral membrane proteins hinder molecular understanding of transmembrane signaling mechanisms. Here, we exploited protein crosslinking assays in living cells to follow conformational and dynamic stimulus signals in Tsr, the Escherichia coli serine chemoreceptor. Tsr mediates serine chemotaxis by integrating transmembrane serine-binding inputs with adaptational modifications of a methylation helix bundle to regulate a signaling kinase at the cytoplasmic tip of the receptor molecule. We created a series of cysteine replacements at Tsr residues adjacent to hydrophobic packing faces of the bundle helices and crosslinked them with a cell-permeable, bifunctional thiol-reagent. We identified an extensively crosslinked dynamic junction midway through the methylation helix bundle that seemed uniquely poised to respond to serine signals. We explored its role in mediating signaling shifts between different packing arrangements of the bundle helices by measuring crosslinking in receptor molecules with apposed pairs of cysteine reporters in each subunit and assessing their signaling behaviors with an in vivo kinase assay. In the absence of serine, the bundle helices evinced compact kinase-ON packing arrangements; in the presence of serine, the dynamic junction destabilized adjacent bundle segments and shifted the bundle to an expanded, less stable kinase-OFF helix-packing arrangement. An AlphaFold 3 model of kinase-active Tsr showed a prominent bulge and kink at the dynamic junction that might antagonize stable structure at the receptor tip. Serine stimuli probably inhibit kinase activity by shifting the bundle to a less stably-packed conformation that relaxes structural strain at the receptor tip, thereby freezing kinase activity.

16.
J Neurotrauma ; 2024 Aug 03.
Article de Anglais | MEDLINE | ID: mdl-39096127

RÉSUMÉ

Repeated mild head injuries due to sports, or domestic violence and military service are increasingly linked to debilitating symptoms in the long term. Although symptoms may take decades to manifest, potentially treatable neurobiological alterations must begin shortly after injury. Better means to diagnose and treat traumatic brain injuries, requires an improved understanding of the mechanisms underlying progression and means through which they can be measured. Here, we employ a repetitive mild closed-head injury (rmTBI) and chronic variable stress (CVS) mouse model to investigate emergent structural and functional brain abnormalities. Brain imaging is achieved with [18F]SynVesT-1 positron emission tomography, with the synaptic vesicle glycoprotein 2A ligand marking synapse density and BOLD (blood-oxygen-level-dependent) functional magnetic resonance imaging (fMRI). Animals were scanned six weeks after concluding rmTBI/Stress procedures. Injured mice showed widespread decreases in synaptic density coupled with an increase in local BOLD-fMRI synchrony detected as regional homogeneity. Injury-affected regions with higher synapse density showed a greater increase in fMRI regional homogeneity. Taken together, these observations may reflect compensatory mechanisms following injury. Multimodal studies are needed to provide deeper insights into these observations.

17.
Rev Environ Health ; 2024 Aug 06.
Article de Anglais | MEDLINE | ID: mdl-39101219

RÉSUMÉ

The present review aimed to evaluate the apoptotic effect of tributyltin (TBT) exposure on mammalian tissues and cells in vivo. A search was conducted in specialized literature databases including Embase, Medline, Pubmed, Scholar Google, and Scopus for all manuscripts using the following keywords: "tributyltin", "apoptosis", "mammals", "mammalian cells', "eukaryotic cells", 'rodents', "rats", "mice" and "in vivo" for all data published until September 2023. A total of 16 studies were included. The studies have demonstrated that TBT exposure induces apoptosis in cells from various mammalian organs or tissues in vivo. TBT is capable to increase apoptotic cells, to activate proapoptotic proteins such as calpain, caspases, bax and beclin-1 and to inhibit antiapoptotic protein bcl-2. Additionally, TBT alters the ratio of bcl-2/bax which favor apoptosis. Therefore, the activation of enzymes such as calpain induces apoptosis mediated by ERS and caspases through the intrinsic apoptosis pathway. This review has demonstrated that TBT exposure induces apoptosis in mammalian tissues and cells in vivo.

18.
Article de Anglais | MEDLINE | ID: mdl-39101251

RÉSUMÉ

PURPOSE: This study aimed to compare in vivo kinematics during weight-bearing daily activities and determine the relationship with clinical outcomes in patients undergoing total knee arthroplasty (TKA) with a medial-pivot (MP, Evolution™) versus a posterior-stabilized (PS, Persona®) design under constant conditions of intraoperative soft tissue balance. METHODS: Forty patients undergoing MP or PS-TKA under similar conditions of soft tissue balance were enrolled in this prospective randomized controlled trial. Outcome measures included clinical knee society scores (KSS) and knee injury and osteoarthritis outcome scores (KOOS). A kinematic assessment was conducted while the participants performed lunge and step-up activities under fluoroscopic guidance. RESULTS: Eighteen patients in each arm completed 1-year follow-up and were included in the analysis. All patients experienced pain relief and satisfactory knee function postoperatively. In kinematics, in the MP arm, the medial femoral condyle remained consistent, whereas the lateral femoral condyle gradually shifted posteriorly with increasing knee flexion. Conversely, in the PS arm, paradoxical anterior movement of the medial femoral condyle accompanied the lateral pivot motion. During lunge and step-up activities, a medial-pivot motion was observed in 83% and 72% of knees in the MP arm, respectively, compared with 22% and 11% in the PS arm. Despite these differences in kinematics, there were no statistically significant differences in the KSS and KOOS between the two groups. CONCLUSION: Under weight-bearing conditions during flexion, knees that underwent Evolution™ MP-TKA did not show superior clinical results compared to Persona® PS-TKA, despite exhibiting in vivo kinematics closely resembling the normal in vivo pattern. LEVEL OF EVIDENCE: Therapeutic studies-Level I.

19.
Chembiochem ; : e202400481, 2024 Aug 05.
Article de Anglais | MEDLINE | ID: mdl-39101874

RÉSUMÉ

Lipid nanoparticles (LNPs) represent an advanced and highly efficient delivery system for RNA molecules, demonstrating exceptional biocompatibility and remarkable delivery efficiency. This is evidenced by the clinical authorization of three LNP formulations: Patisiran, BNT162b2, and mRNA-1273. To further maximize the efficacy of RNA-based therapy, it is imperative to develop more potent LNP delivery systems that can effectively protect inherently unstable and negatively charged RNA molecules from degradation by nucleases, while facilitating their cellular uptake into target cells. Therefore, this review presents feasible strategies commonly employed for the development of efficient LNP delivery systems. The strategies encompass combinatorial chemistry, a rational design approach, the derivatization strategy of functional molecules, the optimization of LNP formulations, and adjustment of particle size and charge property of LNPs. Prior to introducing these developing strategies, in vivo delivery processes of LNPs, a crucial determinant influencing the clinical translation of LNP formulations, is described to better understand how to develop LNP delivery systems.

20.
Pflugers Arch ; 2024 Aug 05.
Article de Anglais | MEDLINE | ID: mdl-39101996

RÉSUMÉ

Hypoxia is relevant to several physiological and pathological processes and this also applies for the tooth. The adaptive response to lowering oxygen concentration is mediated by hypoxia-inducible factors (HIFs). Since HIFs were shown to participate in the promotion of angiogenesis, stem cell survival, odontoblast differentiation and dentin formation, they may play a beneficial role in the tooth reparative processes. Although some data were generated in vitro, little is known about the in vivo context of HIFs in tooth development. In order to contribute to this field, the mouse mandibular first molar was used as a model.The expression and in situ localisation of HIFs were examined at postnatal (P) days P0, P7, P14, using RT-PCR and immunostaining. The expression pattern of a broad spectrum of hypoxia-related genes was monitored by customised PCR Arrays. Metabolic aspects were evaluated by determination of the lactate level and mRNA expression of the mitochondrial marker Nd1.The results show constant high mRNA expression of Hif1a, increasing expression of Hif2a, and very low expression of Hif3a during early postnatal molar development. In the examined period the localisation of HIFs in the nuclei of odontoblasts and the subodontoblastic layer identified their presence during odontoblastic differentiation. Additionally, the lower lactate level and higher expression of mitochondrial Nd1 in advanced development points to decreasing glycolysis during differentiation. Postnatal nuclear localisation of HIFs indicates a hypoxic state in specific areas of dental pulp as oxygen demands depend on physiological events such as crown and root dentin mineralization.

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