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3D printed scaffolds have revolutionized the field of regenerative medicine by overcoming the lacunas such as precision, customization, and reproducibility observed through traditional methods of scaffold preparation such as freeze-drying, electrospinning, etc. Combining the advantages of 3D printed scaffolds along with bioactive cues such as signaling molecules can be an effective treatment approach. In the present study, cellulose nanocrystals (CNCs) along with gelatin, in different ratios, were used for scaffold preparation through the direct ink writing technique and thoroughly characterized. The scaffolds showed porous microstructure, high swelling ratio (â¼390 to 590), degradability and porosity (â¼65 %). In vitro biocompatibility assays showed high biocompatibility and no toxicity through live-dead, proliferation and hemolysis assay. Further, the optimum formulation was functionalized with nitric oxide (NO)-releasing modified gelatin to enhance the scaffold's biomedical applicability. Functionality assays with this formulation, scratch, and neurite outgrowth showed positive effects of NO on cell migration and neurite length. The study presents the fabrication, modification, and biomedical applicability of the aforementioned inks, which paves new pathways in the field of 3D printing of scaffolds with significant potential for biomedical applications, soft tissue engineering, and wound dressing, for example.
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BACKGROUND: The mechanisms enabling dynamic shifts between drug-resistant and drug-sensitive states in cancer cells are still underexplored. This study investigated the role of targeted autophagic protein degradation in regulating ovarian cancer stem cell (CSC) fate decisions and chemo-resistance. METHODS: Autophagy levels were compared between CSC-enriched side population (SP) and non-SP cells (NSP) in multiple ovarian cancer cell lines using immunoblotting, immunofluorescence, and transmission electron microscopy. The impact of autophagy modulation on CSC markers and differentiation was assessed by flow cytometry, immunoblotting and qRT-PCR. In silico modeling and co-immunoprecipitation identified ID1 interacting proteins. Pharmacological and genetic approaches along with Annexin-PI assay, ChIP assay, western blotting, qRT-PCR and ICP-MS were used to evaluate effects on cisplatin sensitivity, apoptosis, SLC31A1 expression, promoter binding, and intracellular platinum accumulation in ID1 depleted backdrop. Patient-derived tumor spheroids were analyzed for autophagy and SLC31A1 levels. RESULTS: Ovarian CSCs exhibited increased basal autophagy compared to non-CSCs. Further autophagy stimulation by serum-starvation and chemical modes triggered proteolysis of the stemness regulator ID1, driving the differentiation of chemo-resistant CSCs into chemo-sensitive non-CSCs. In silico modeling predicted TCF12 as a potent ID1 interactor, which was validated by co-immunoprecipitation. ID1 depletion freed TCF12 to transactivate the cisplatin influx transporter SLC31A1, increasing intracellular cisplatin levels and cytotoxicity. Patient-derived tumor spheroids exhibited a functional association between autophagy, ID1, SLC31A1, and platinum sensitivity. CONCLUSIONS: This study reveals a novel autophagy-ID1-TCF12-SLC31A1 axis where targeted autophagic degradation of ID1 enables rapid remodeling of CSCs to reverse chemo-resistance. Modulating this pathway could counter drug resistance in ovarian cancer.
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Autofagia , Resistencia a Medicamentos Antineoplásicos , Proteína 1 Inibidora de Diferenciação , Células-Tronco Neoplásicas , Neoplasias Ovarianas , Humanos , Feminino , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Proteína 1 Inibidora de Diferenciação/metabolismo , Proteína 1 Inibidora de Diferenciação/genética , Linhagem Celular Tumoral , Cisplatino/farmacologiaRESUMO
PURPOSE: In chronic hyperglycemia, the advanced glycation end product (AGE) interacts with its receptor (RAGE) and contributes to impaired wound healing by inducing oxidative stress, generating dysfunctional macrophages, and prolonging the inflammatory response. Additionally, uncontrolled levels of proteases, including metallomatrix protease-9 (MMP-9), in the diabetic wound bed degrade the extracellular matrix (ECM) and biological cues that augment healing. A multifunctional antimicrobial hydrogel (Immuno-gel) containing RAGE and MMP-9 inhibitors can regulate the wound microenvironment and promote scar-free healing. RESULTS: Immuno-gel was characterized and the wound healing efficacy was determined in vitro cell culture and in vivo diabetic Wistar rat wound model using ELISA, Western blot, and Immunofluorescence staining. The Immuno-gel exhibited a highly porous morphology with excellent in vitro cytocompatibility. AGE-stimulated macrophages treated with the Immuno-gel released higher levels of pro-healing cytokines in vitro. In the hydrogel-wound interface of diabetic Wistar rats, Immuno-gel treatment significantly reduced MMP-9 and NF-κB expression and enhanced pro-healing (M2) macrophage population and pro-healing cytokines. CONCLUSION: Altogether, this study suggests that Immuno-gel simultaneously attenuates macrophage dysfunction through the inhibition of AGE/RAGE signaling and reduces MMP-9 overexpression, both of which favor scar-free healing. The combinatorial treatment with RAGE and MMP-9 inhibitors via Immuno-gel simultaneously modulates the diabetic wound microenvironment, making it a promising novel treatment to accelerate diabetic wound healing.
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Diabetes Mellitus Experimental , Produtos Finais de Glicação Avançada , Hidrogéis , Metaloproteinase 9 da Matriz , Ratos Wistar , Receptor para Produtos Finais de Glicação Avançada , Transdução de Sinais , Cicatrização , Animais , Metaloproteinase 9 da Matriz/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Cicatrização/efeitos dos fármacos , Hidrogéis/farmacologia , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Ratos , Transdução de Sinais/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/imunologia , Masculino , CamundongosRESUMO
Casein kinase 1α (CK1α) is a serine/threonine protein kinase that acts in various cellular processes affecting cell division and signal transduction. CK1α is present as multiple splice variants that are distinguished by the presence or absence of a long insert (L-insert) and a short carboxyl-terminal insert (S-insert). When overexpressed, zebrafish CK1α splice variants exhibit different biological properties, such as subcellular localization and catalytic activity. However, whether endogenous, alternatively spliced CK1α gene products also differ in their biological functions has yet to be elucidated. Here, we identify a panel of splice variant specific CK1α antibodies and use them to show that four CK1α splice variants are expressed in mammals. We subsequently show that the relative abundance of CK1α splice variants varies across distinct mouse tissues and between various cancer cell lines. Furthermore, we identify pathways whose expression is noticeably altered in cell lines enriched with select splice variants of CK1α. Finally, we show that the S-insert of CK1α promotes the growth of HCT 116 cells as cells engineered to lack the S-insert display decreased cell growth. Together, we provide tools and methods to identify individual CK1α splice variants, which we use to begin to uncover the differential biological properties driven by specific splice variants of mammalian CK1α.
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Processamento Alternativo , Caseína Quinase Ialfa , Animais , Humanos , Camundongos , Caseína Quinase Ialfa/metabolismo , Caseína Quinase Ialfa/genética , Linhagem Celular Tumoral , Proliferação de Células , Células HCT116 , Isoenzimas/genética , Isoenzimas/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologiaRESUMO
Cardiovascular diseases (CVDs) continue to be a worldwide health concern, requiring effective strategies for risk reduction. This article explores the extensive collaboration between medical therapy and lifestyle modifications in the management of CVDs, aiming to interpret whether a single approach holds the key to reducing major cardiovascular events. In the realm of pharmaceutical therapy, statins, beta-blockers, angiotensin-converting-enzyme (ACE) inhibitors, and antiplatelet agents have shown significant effectiveness, as evidenced by landmark trials such as Scandinavian Simvastatin Survival Study (4S) and Heart Outcomes Prevention Evaluation (HOPE). Concurrently, lifestyle adjustments, encompassing physical activity, dietary changes, and management of stress, emerge as indispensable elements in cardiovascular care. The article discusses the pivotal role of patient adherence, tailored approaches, and the synergistic impact of combining medical therapy and lifestyle modifications. Challenges, such as socioeconomic disparities and uncertainties in lipid management, underscore the need for ongoing research and precision medicine. Digital health interventions offer novel avenues for personalized care. Despite advancements, uncertainties persist regarding the optimal balance between medical and lifestyle interventions in lowering major cardiovascular event risks. This article emphasizes the ongoing evolution of cardiovascular care, highlighting the imperative need for evidence-based guidelines tailored to individual patient needs.
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The impairment of phenotype switching of pro-inflammatory M1 to pro-healing M2 macrophage induced by hyperglycemic microenvironment often elevates oxidative stress, impairs angiogenesis, and leads to chronic non-healing wounds in diabetic patients. Administration of M2 macrophage-derived exosomes (M2Exo) at wound site is known to polarize M1 to M2 macrophage and can accelerate wound healing by enhancing collagen deposition, angiogenesis, and re-epithelialization. In the present study, M2Exo were conjugated with oxidized hyaluronic acid and mixed with PEGylated silk fibroin to develop self-healing Exo-gel to achieve an efficient therapy for diabetic wounds. Exo-gel depicted porous networked morphology with self-healing and excellent water retention behaviour. Fibroblast cells treated with Exo-gel showed significant uptake of M2Exo that increased their proliferation and migration in vitro. Interestingly, in a diabetic wound model of wistar rats, Exo-gel treatment induced 75 % wound closure within 7 days with complete epithelial layer regeneration by modulating cytokine levels, stimulating fibroblast-keratinocyte interaction and migration, angiogenesis, and organized collagen deposition. Taken together, this study suggests that Exo-gel depict properties of an excellent wound healing matrix and can be used as a therapeutic alternative to treat chronic non-healing diabetic wounds.
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Exossomos , Ácido Hialurônico , Hidrogéis , Macrófagos , Cicatrização , Ácido Hialurônico/química , Ácido Hialurônico/farmacologia , Animais , Exossomos/metabolismo , Cicatrização/efeitos dos fármacos , Ratos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Hidrogéis/química , Hidrogéis/farmacologia , Diabetes Mellitus Experimental , Ratos Wistar , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Masculino , Camundongos , Seda/química , Seda/farmacologia , Microambiente Celular/efeitos dos fármacos , Humanos , Proliferação de Células/efeitos dos fármacos , Movimento Celular/efeitos dos fármacosRESUMO
Nitric oxide (NO) holds promise as a cytotoxic agent against tumors, but its gaseous nature and short half-life hinder direct administration to tumor tissues. Herein, we present novel 6,9-disubstituted purine derivatives designed to ensure sustained NO release, followed by study of their significant anti-proliferative, anti-migratory, and anti-clonogenic effects on HepG2 cell lines, highlighting NO release as a potent effector for treating hepatocellular carcinoma.
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Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Óxido Nítrico/metabolismo , Células Hep G2 , Proliferação de Células , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias Hepáticas/patologia , Linhagem Celular Tumoral , ApoptoseRESUMO
The main goal of bone tissue engineering research is to replace the allogenic and autologous bone graft substitutes that can promote bone repair. Owing to excellent biocompatibility and osteoconductivity, hydroxyapatite is in extensive research and high demand for both medical and non-medical applications. Although various methods have been developed for the synthesis of hydroxyapatite, in the present study we have shown the use of nanosecond laser energy in the wet precipitation method of nano-hydroxyapatite (nHAP) synthesis without using ammonium solution or any other chemicals for pH maintenance. Here, the present study aimed to fabricate the nanohydroxyapatite using a nanosecond laser. The X-ray diffraction and Fourier transform infrared spectroscopy have confirmed the hydroxyapatite formation under laser irradiation in less time without aging. A transmission electron microscopy confirmed the nano size of synthesized nHAP, which is comparable to conventional nHAP. The length and width of the laser-assisted nHAP were found to be in the range of 50-200â¯nm and 15-20â¯nm, respectively, at various laser parameters. The crystallite size obtained by Debye Scherrer formulae was found to be in the range of â¼ 16-36â¯nm. In addition, laser-assisted nHAP based composite cryogel (nanohydroxyapatite/gelatin/collagen I) was synthesized and impregnated with bioactive molecules (bone morphogenic protein and zoledronic acid) that demonstrated significant osteogenic potential both in vitro in cell experiment and in vivo rat muscle pouch model (abdomen and tibia muscles). Dual-energy X-ray analysis, micro-CT, and histological analysis confirmed ectopic bone regeneration. Micro-CT based histomorphometry showed a higher amount (more than 10-fold) of mineralization for animal groups implanted with composite cryogels loaded with bioactive molecules compared to only composite cryogels groups. Our findings thus demonstrate a controlled and rapid synthetic method for the synthesis of nHAP with various physical, chemical, and biological properties exhibited as comparable to conventionally synthesized nHAP.
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Criogéis , Durapatita , Pirenos , Ratos , Animais , Durapatita/farmacologia , Durapatita/química , Regeneração Óssea/fisiologia , Osso e Ossos , Alicerces Teciduais/químicaRESUMO
Introduction Hemophilia is an uncommon, X-linked recessive bleeding condition characterized by a lack of either factor VIII or factor IX. It is more prevalent in men. Due to the substantial impact inhibitor development has on patient prognosis, the primary treatment for hemophilia is the transfusion of recombinant factors. The aim of our study is to investigate 40 adult patients with hemophilia in terms of their clinical profile, clinically relevant risk factors for inhibitor development, therapy-related aspects such as treatment duration, factor requirements, transfusion frequency, presence of inhibitors, and complications. Methods This cross-sectional observational study involving 40 patients of hemophilia over 12 years of age was conducted at a tertiary care hospital in Gujarat. Data on sociodemographic characteristics, presenting complaints, bleeding episodes, hemophilia type, and medical history were gathered over a one-year span. Patients were stratified into mild, moderate, and severe groups based on their respective levels of factor activity. Various parameters, including the frequency of factor therapy, percentage of factor concentrate, inhibitor presence, and disease and therapy-related complications, were analyzed. The distribution of patients across these parameters was calculated and illustrated using pie charts. Results Nineteen out of 40 patients were from 20 to 40 years of age. The majority of cases (n=24), however, had been diagnosed before the patients reached the age of 10. All patients were male, and half of the patients (n=20) suffered from mild disease. The most common site of bleeding was the knee joint, and 33 cases had one to 10 bleeding episodes per year. Thirty-two out of 40 patients needed less than 40 factor vial transfusions, whereas eight needed more than 40 factor vial transfusions. Two cases of severe disease were positive for inhibitors of factor VIII, whereas one patient was found to have a hepatitis B virus (HBV) infection. Conclusions Hemophilia, a rare bleeding disorder, has primarily been studied in pediatric populations. This study, however, shifts the focus toward adult individuals. Our cohort consisted exclusively of male patients, with the predominant group diagnosed with hemophilia A and falling within the age range of 20 to 40 years. Most patients had been diagnosed before 10 years of age. The primary complication observed was joint bleeding, with the knee joint being the most commonly affected site. Approximately two-thirds of cases had a history of minor trauma necessitating factor replacement, yet only 5% exhibited the presence of inhibitors.
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Understanding the coevolutionary dynamics of hosts and their parasites remains a major focus of much theoretical literature. Despite empirical evidence supporting the presence of sterility-mortality tolerance trade-offs in hosts and recovery-transmission trade-offs in parasites, none of the current models have explored the potential outcomes when both trade-offs are considered within a coevolutionary framework. In this study, we consider a model where the host evolves sterility tolerance at the cost of increased mortality and the parasite evolves higher transmission rate at the cost of increased recovery rate (reduced infection duration), and use adaptive dynamics to predict the coevolutionary outcomes under such trade-off assumptions. We particularly aim to understand how our coevolutionary dynamics compare with single species evolutionary models. We find that evolutionary branching in the host can drive the parasite population to branch, but that cycles in the population dynamics can prevent the coexisting strains from reaching their extremes. We also find that varying crowding does not impact the recovery rate when only the parasite evolves, yet coevolution reduces recovery as crowding intensifies. We conclude by discussing how different host and parasite trade-offs shape coevolutionary outcomes, underscoring the pivotal role of trade-offs in coevolution.
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Infertilidade , Parasitos , Animais , Interações Hospedeiro-Parasita , Evolução Biológica , Dinâmica PopulacionalRESUMO
Background: Recent studies have used basic epicardial adipose tissue (EAT) assessments (e.g., volume and mean HU) to predict risk of atherosclerosis-related, major adverse cardiovascular events (MACE). Objectives: Create novel, hand-crafted EAT features, "fat-omics", to capture the pathophysiology of EAT and improve MACE prediction. Methods: We segmented EAT using a previously-validated deep learning method with optional manual correction. We extracted 148 radiomic features (morphological, spatial, and intensity) and used Cox elastic-net for feature reduction and prediction of MACE. Results: Traditional fat features gave marginal prediction (EAT-volume/EAT-mean-HU/BMI gave C-index 0.53/0.55/0.57, respectively). Significant improvement was obtained with 15 fat-omics features (C-index=0.69, test set). High-risk features included volume-of-voxels-having-elevated-HU-[-50, -30-HU] and HU-negative-skewness, both of which assess high HU, which as been implicated in fat inflammation. Other high-risk features include kurtosis-of-EAT-thickness, reflecting the heterogeneity of thicknesses, and EAT-volume-in-the-top-25%-of-the-heart, emphasizing adipose near the proximal coronary arteries. Kaplan-Meyer plots of Cox-identified, high- and low-risk patients were well separated with the median of the fat-omics risk, while high-risk group having HR 2.4 times that of the low-risk group (P<0.001). Conclusion: Preliminary findings indicate an opportunity to use more finely tuned, explainable assessments on EAT for improved cardiovascular risk prediction.
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Acute myeloid leukemia (AML) with fms-like tyrosine kinase 3 internal tandem duplication (FLT3-ITD) has poor outcomes. FLT3-ITD drives constitutive and aberrant FLT3 signaling, activating STAT5 and upregulating the downstream oncogenic serine/threonine kinase Pim-1. FLT3 inhibitors are in clinical use, but with limited and transient efficacy. We previously showed that concurrent treatment with Pim and FLT3 inhibitors increases apoptosis induction in FLT3-ITD-expressing cells through posttranslational downregulation of Mcl-1. Here we further elucidate the mechanism of action of this dual targeting strategy. Cytotoxicity, apoptosis and protein expression and turnover were measured in FLT3-ITD-expressing cell lines and AML patient blasts treated with the FLT3 inhibitor gilteritinib and/or the Pim inhibitors AZD1208 or TP-3654. Pim inhibitor and gilteritinib cotreatment increased apoptosis induction, produced synergistic cytotoxicity, downregulated c-Myc protein expression, earlier than Mcl-1, increased turnover of both proteins, which was rescued by proteasome inhibition, and increased efficacy and prolonged survival in an in vivo model. Gilteritinib and Pim inhibitor cotreatment of Ba/F3-ITD cells infected with T58A c-Myc or S159A Mcl-1 plasmids, preventing phosphorylation at these sites, did not downregulate these proteins, increase their turnover or increase apoptosis induction. Moreover, concurrent treatment with gilteritinib and Pim inhibitors dephosphorylated (activated) the serine/threonine kinase glycogen synthase kinase-3ß (GSK-3ß), and GSK-3ß inhibition prevented c-Myc and Mcl-1 downregulation and decreased apoptosis induction. The data are consistent with c-Myc T58 and Mcl-1 S159 phosphorylation by activated GSK-3ß as the mechanism of action of gilteritinib and Pim inhibitor combination treatment, further supporting GSK-3ß activation as a therapeutic strategy in FLT3-ITD AML. SIGNIFICANCE: FLT3-ITD is present in 25% of in AML, with continued poor outcomes. Combining Pim kinase inhibitors with the FDA-approved FLT3 inhibitor gilteritinib increases cytotoxicity in vitro and in vivo through activation of GSK-3ß, which phosphorylates and posttranslationally downregulates c-Myc and Mcl-1. The data support efficacy of GSK-3ß activation in FLT3-ITD AML, and also support development of a clinical trial combining the Pim inhibitor TP-3654 with gilteritinib.
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Compostos de Anilina , Leucemia Mieloide Aguda , Pirazinas , Tirosina Quinase 3 Semelhante a fms , Humanos , Glicogênio Sintase Quinase 3 beta/genética , Tirosina Quinase 3 Semelhante a fms/genética , Proteínas Serina-Treonina Quinases/uso terapêutico , Inibidores de Proteínas Quinases/farmacologia , Leucemia Mieloide Aguda/tratamento farmacológico , Serina/metabolismoRESUMO
The process of integration of inputs from several sensory modalities in the human brain is referred to as multisensory integration. Age-related cognitive decline leads to a loss in the ability of the brain to conceive multisensory inputs. There has been considerable work done in the study of such cognitive changes for the old age groups. However, in the case of middle age groups, such analysis is limited. Motivated by this, in the current work, EEG-based functional connectivity during audiovisual temporal asynchrony integration task for middle-aged groups is explored. Investigation has been carried out during different tasks such as: unimodal audio, unimodal visual, and variations of audio-visual stimulus. A correlation-based functional connectivity analysis is done, and the changes among different age groups including: young (18-25 years), transition from young to medium age (25-33 years), and medium (33-41 years), are observed. Furthermore, features extracted from the connectivity graphs have been used to classify among the different age groups. Classification accuracies of 89.4% and 88.4% are obtained for the Audio and Audio-50-Visual stimuli cases with a Random Forest based classifier, thereby validating the efficacy of the proposed method.
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Percepção Auditiva , Percepção Visual , Pessoa de Meia-Idade , Humanos , Adolescente , Adulto Jovem , Adulto , Tempo de Reação , Encéfalo , Mapeamento EncefálicoRESUMO
Swati PabbiIntroduction Multiple myeloma (MM) forms a significant proportion of hematological malignancies. Autologous transplantation continues to be an effective consolidation strategy in resource-restricted settings such as India. Objectives The main objective of the study was to analyze the clinical outcomes of autologous hematopoietic stem cell transplant (HSCT) in MM patients in a single tertiary care center in north India over a period of 5 years. Materials and Methods This retrospective observational study was conducted in a tertiary care center in north India. Data of all MM patients who underwent HSCT between January 2014, and December 2018, were analyzed. The outcome of HSCT was investigated in terms of transplant-related mortality (TRM), progression-free survival (PFS), overall survival (OS), and relapse. PFS and OS were calculated by Kaplan-Meier method and differences between the groups were tested for statistical significance using the two-tailed log-rank test. Life-table method was used for the estimation of survival rate at 1, 3, 5, and 6 years. Results Patient characteristics and survival post-transplant was similar to other published Indian studies. In total, 378 patients were diagnosed with MM in our hospital between 2014 and 2018. One hundred ninety-three patients were found to be eligible for autologous HSCT, out of which 52 ended up having a transplant giving us a high percentage (26.9%) of patients receiving a transplant in our setting. Transplant-related mortality (TRM) was nil in the present study. The mean PFS and OS were 62.8 and 70.1 months, respectively. The mean PFS and OS rates at 5 years were 75.3% and 84.2%, respectively. The average cost estimate of HSCT in our setting was 7.2 lakh Indian national rupees. Conclusion Autologous HSCT is a safe procedure with nil 100-day mortality in present series. Moreover, considering the cost of novel agents, autologous transplant remains a cost-effective way for prolonging remission and time-to-next treatment in India.
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Traditional metal-alloy bone fixation devices provide structural support for bone repair but have limitations in actively promoting bone healing and often require additional surgeries for implant removal. In this study, we focused on addressing these challenges by fabricating biodegradable composites using poly(lactic acid) (PLA) and strontium-substituted nanohydroxyapatite (SrHAP) via melt compounding and injection molding. Various percentages of SrHAP (5, 10, 20, and 30% w/w) were incorporated into the PLA matrix. We systematically investigated the structural, morphological, thermal, mechanical, rheological, and dynamic mechanical properties of the prepared composites. Notably, the tensile modulus, a critical parameter for orthopedic implants, significantly improved from 2.77 GPa in pristine PLA to 3.73 GPa in the composite containing 10% w/w SrHAP. The incorporation of SrHAP (10% w/w) into the PLA matrix led to an increased storage modulus, indicating a uniform dispersion of SrHAP within the PLA and good compatibility between the polymer and nanoparticles. Moreover, we successfully fabricated screws using PLA composites with 10% (w/w) SrHAP, demonstrating their formability at room temperature and radiopacity when observed under X-ray microtomography (micro-CT). Furthermore, the water contact angle decreased from 93 ± 2° for pristine PLA to 75 ± 3° for the composite containing SrHAP, indicating better surface wettability. To assess the biological behavior of the composites, we conducted in vitro cell-material tests, which confirmed their osteoconductive and osteoinductive properties. These findings highlight the potential of our developed PLA/SrHAP10 (10% w/w) composites as machinable implant materials for orthopedic applications. In conclusion, our study presents the fabrication and comprehensive characterization of biodegradable composites comprising PLA and strontium-substituted nanohydroxyapatite (SrHAP). These composites exhibit improved mechanical properties, formability, and radiopacity while also demonstrating desirable biological behavior. Our results suggest that these PLA/SrHAP10 composites hold promise as machinable implant materials for orthopedic applications.
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Poliésteres , Estrôncio , Poliésteres/química , Polímeros/química , Próteses e ImplantesRESUMO
Developing advanced methods for effective bone reconstructive strategies in case of critical bone defects caused by tumor resection, trauma, and other implant-related complications remains a challenging problem in orthopedics. In the clinical management of bone diseases, there is a paradigm shift in using local drugs at the injury site; however, the dead space created during the surgical debridement of necrotic bone and soft tissues (periosteum and underlying muscle) leads to ineffective bone formation, thereby leading to secondary complications, and thus calls for better regenerative approaches. In this study, we have utilized an exosome-functionalized doxorubicin-loaded biodegradable nanocement (NC)-based carrier along with a Cissus quadrangularis (CQ) extract-laden antioxidant herbal membrane for simultaneously managing the periosteum as well as bone formation in the tumor resection model of osteosarcoma. We initially evaluated the efficacy of scaffolds for in vitro mineralization and bone formation. To examine the in vivo effectiveness, we developed a human osteosarcoma cell line (Saos-2)-induced tumor xenograft model with a critical-sized bone defect. The findings revealed that doxorubicin released from NC was successful in killing the tumor cells and was present even after 30 days of implantation. Additionally, the incorporation of exosomes aided the bone formation, resulting in around a 2.6-fold increase in the bone volume compared to the empty group as evaluated by micro-CT. The herbal membrane assisted in the development of periosteum and mineralizing bone callous as validated through histological and immunofluorescence analysis. Thus, our findings describe a one-step biomaterial-based cell-free approach to regenerate bone in osteosarcoma and prevent further fracture due to the complete development of periosteum and lost bone.
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Epithelial ovarian cancer (EOC) is the deadliest gynaecological malignancy and the eighth most prevalent cancer in women, with an abysmal mortality rate of two million worldwide. The existence of multiple overlapping symptoms with other gastrointestinal, genitourinary, and gynaecological maladies often leads to late-stage diagnosis and extensive extra-ovarian metastasis. Due to the absence of any clear early-stage symptoms, current tools only aid in the diagnosis of advanced-stage patients, wherein the 5-year survival plummets further to less than 30%. Therefore, there is a dire need for the identification of novel approaches that not only allow early diagnosis of the disease but also have a greater prognostic value. Toward this, biomarkers provide a gamut of powerful and dynamic tools to allow the identification of a spectrum of different malignancies. Both serum cancer antigen 125 (CA-125) and human epididymis 4 (HE4) are currently being used in clinics not only for EOC but also peritoneal and GI tract cancers. Screening of multiple biomarkers is gradually emerging as a beneficial strategy for early-stage diagnosis, proving instrumental in administration of first-line chemotherapy. These novel biomarkers seem to exhibit an enhanced potential as a diagnostic tool. This review summarizes existing knowledge of the ever-growing field of biomarker identification along with potential future ones, especially for ovarian cancer.
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While experimental studies have demonstrated within-population variation in host tolerance to parasitism, theoretical studies rarely predict for polymorphism to arise. However, most theoretical models do not consider the crucial distinction between tolerance to the effects of infection-induced deaths (mortality tolerance) and tolerance to the parasite-induced reduction in the reproduction of infected hosts (sterility tolerance). While some studies have examined trade-offs between host tolerance and resistance mechanisms, none has considered a correlation within different tolerance mechanisms. We assume that sterility tolerance and mortality tolerance are directly traded-off in a host population subjected to a pathogen and use adaptive dynamics to study their evolutionary behaviour. We find that such a trade-off between the two tolerance strategies can drive the host population to branch into dimorphic strains, leading to coexistence of strains with sterile hosts that have low mortality and fully fertile with high mortality rates. Further, we find that a wider range of trade-off shapes allows branching at intermediate- or high-infected population size. Our other significant finding is that sterility tolerance is maximised (and mortality tolerance minimised) at an intermediate disease-induced mortality rate. Additionally, evolution entirely reverses the disease prevalence pattern corresponding to the recovery rate, compared to when no strategies evolve. We provide novel predictions on the evolutionary behaviour of two tolerance strategies concerning such a trade-off.
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Interações Hospedeiro-Parasita , Modelos Biológicos , Humanos , Conceitos MatemáticosRESUMO
Cognitive brain aging can either be healthy or degenerative in nature. Multiple alterations occur in brain networks with healthy aging. Much of this has yet to be investigated. This study seeks to understand the typical healthy human brain's developmental stages using a publicly available dataset from the human connectome project. As the human brain's developmental stage varies, we also intend to identify a pattern of reorganization in the resting state functional connectivity of several brain networks. The results are specifically presented based on the resting state BOLD signals of 1096 healthy volunteers between the age group of 7-89 years. The k-means clustering method has been used to determine the various human brain developmental stages. Using the t-SNE technique, the clusters are visually separated. BrainNet Viewer is used to study the changes in resting state functional connectivity of the entire brain as the human brain developmental stages vary. The age-related pattern of change in the resting state functional connectivity of six Dosenbasch brain networks that were grouped using the k-means elbow approach has been additionally presented. For performance evaluation, three metrics of brain network connection including network segregation, between network connectivity, and within-network connectivity are used. As the age cohort changes, a consistent pattern in the variance of these connection indices is seen for different Dosenbasch brain networks. Thus, the study's findings suggest that healthy aging causes a functional reorganization of the resting state brain network connections.
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Mapeamento Encefálico , Conectoma , Humanos , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética/métodos , Vias Neurais , Encéfalo , Análise por Conglomerados , Rede Nervosa/diagnóstico por imagemRESUMO
Arabinogalactan proteins are functionally diverse cell wall structural glycoproteins that have been implicated in cell wall remodeling, although the mechanistic actions remain elusive. Here, we identify and characterize two AGP glycoproteins, SLEEPING BEAUTY (SB) and SB-like (SBL), that negatively regulate the gametophore bud initiation in Physcomitrium patens by dampening cell wall loosening/softening. Disruption of SB and SBL led to accelerated gametophore formation and altered cell wall compositions. The function of SB is glycosylation dependent and genetically connected with the class C auxin response factor (ARF) transcription factors PpARFC1B and PpARFC2. Transcriptomics profiling showed that SB upregulates PpARFC2, which in turn suppresses a range of cell wall-modifying genes that are required for cell wall loosening/softening. We further show that PpARFC2 binds directly to multiple AuxRE motifs on the cis-regulatory sequences of PECTIN METHYLESTERASE to suppress its expression. Hence, our results demonstrate a mechanism by which the SB modulates the strength of intracellular auxin signaling output, which is necessary to fine-tune the timing of gametophore initials formation.