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Soft and biological matter come in a variety of shapes and geometries. When soft surfaces that do not fit into each other due to a mismatch in Gaussian curvatures form an interface, beautiful geometry-induced patterns are known to emerge. In this paper, we study the effect of geometry on the dynamical response of soft surfaces moving relative to each other. Using a simple experimental scheme, we measure friction between a highly bendable thin polymer sheet and a hydrogel substrate. At this soft and low-friction interface, we find a strong dependence of friction on the relative geometry of the two surfaces-a flat sheet experiences significantly larger friction on a spherical substrate than on flat or cylindrical substrate. We show that the stress developed in the sheet due to its geometrically incompatible confinement is responsible for the enhanced friction. This mechanism also leads to a transition in the nature of friction as the sheet radius is increased beyond a critical value. Our finding reveals a hitherto unnoticed mechanism based on an interplay between geometry and elasticity that may influence friction significantly in soft, biological, and nanoscale systems. In particular, it provokes us to reexamine our understanding of phenomena such as the curvature dependence of biological cell mobility.
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Connexin hemichannels were identified as the first members of the eukaryotic large-pore channel family that mediate permeation of both atomic ions and small molecules between the intracellular and extracellular environments. The conventional view is that their pore is a large passive conduit through which both ions and molecules diffuse in a similar manner. In stark contrast to this notion, we demonstrate that the permeation of ions and of molecules in connexin hemichannels can be uncoupled and differentially regulated. We find that human connexin mutations that produce pathologies and were previously thought to be loss-of-function mutations due to the lack of ionic currents are still capable of mediating the passive transport of molecules with kinetics close to those of wild-type channels. This molecular transport displays saturability in the micromolar range, selectivity, and competitive inhibition, properties that are tuned by specific interactions between the permeating molecules and the N-terminal domain that lies within the pore-a general feature of large-pore channels. We propose that connexin hemichannels and, likely, other large-pore channels, are hybrid channel/transporter-like proteins that might switch between these two modes to promote selective ion conduction or autocrine/paracrine molecular signaling in health and disease processes.
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Conexinas , Humanos , Conexinas/metabolismo , Conexinas/genética , Transporte de Íons , Animais , Mutação , Íons/metabolismo , Junções Comunicantes/metabolismo , Canais Iônicos/metabolismo , Canais Iônicos/genéticaRESUMO
BACKGROUND AND AIMS: In obesity, depletion of KCs expressing CRIg (complement receptor of the Ig superfamily) leads to microbial DNA accumulation, which subsequently triggers tissue inflammation and insulin resistance. However, the mechanism underlying obesity-mediated changes in KC complement immune functions is largely unknown. APPROACH AND RESULTS: Using KC-specific deactivated Cas9 transgenic mice treated with guide RNA, we assessed the effects of restoring CRIg or the serine/arginine-rich splicing factor 3 (SRSF3) abundance on KC functions and metabolic phenotypes in obese mice. The impacts of weight loss on KC responses were evaluated in a diet switch mouse model. The role of SRSF3 in regulating KC functions was also evaluated using KC-specific SRSF3 knockout mice. Here, we report that overexpression of CRIg in KCs of obese mice protects against bacterial DNA accumulation in metabolic tissues. Mechanistically, SRSF3 regulates CRIg expression, which is essential for maintaining the CRIg+ KC population. During obesity, SRSF3 expression decreases, but it is restored with weight loss through a diet switch, normalizing CRIg+ KCs. KC SRSF3 is also repressed in obese human livers. Lack of SRSF3 in KCs in lean and obese mice decreases their CRIg+ population, impairing metabolic parameters. During the diet switch, the benefits of weight loss are compromised due to SRSF3 deficiency. Conversely, SRSF3 overexpression in obese mice preserves CRIg+ KCs and improves metabolic responses. CONCLUSIONS: Restoring SRSF3 abundance in KCs offers a strategy against obesity-associated tissue inflammation and insulin resistance by preventing bacterial DNA accumulation.
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Resistência à Insulina , Células de Kupffer , Obesidade , Fatores de Processamento de Serina-Arginina , Animais , Fatores de Processamento de Serina-Arginina/metabolismo , Fatores de Processamento de Serina-Arginina/genética , Obesidade/metabolismo , Camundongos , Células de Kupffer/metabolismo , Humanos , Masculino , Camundongos Transgênicos , Camundongos Knockout , Modelos Animais de Doenças , Camundongos Endogâmicos C57BLRESUMO
mTOR inhibitors such as sirolimus are increasingly used in the management of multilineage immune cytopenia (m-IC) in children. Although sirolimus is effective in improving IC, it is unclear how sirolimus affects the broader immune dysregulation associated with m-IC. We profiled T- and B-cell subsets longitudinally and measured cytokines and chemokines before and after sirolimus treatment. Eleven of the 12 patients with m-IC who tolerated sirolimus were followed for a median duration of 17 months. All patients had an improvement in IC, and sirolimus therapy did not result in significant decreases in T-, B- and NK-cell numbers. However, the expansion and activation of circulating T follicular helper and the Th1 bias noted before the initiation of sirolimus were significantly decreased. Features of chronic T-cell activation and exhaustion within effector memory compartments of CD4+ and CD8+ T cells decreased with sirolimus therapy. Corresponding to these changes, plasma levels of CXCL9 and CXCL10 also decreased. Interestingly, no significant improvement in the proportion of class-switched memory B cells or frequencies of CD4+ naive T cells were noted. Longer follow-up and additional studies are needed to validate these findings and evaluate the effect of sirolimus on B-cell maturation.
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Subpopulações de Linfócitos B , Linfócitos T CD4-Positivos , Criança , Humanos , Sirolimo/farmacologia , Sirolimo/uso terapêutico , Serina-Treonina Quinases TOR , Linfócitos T CD8-PositivosRESUMO
Hemophagocytic lymphohistiocytosis (HLH) is characterized by hyperinflammation and multiorgan dysfunction. Infections, including the reactivation of viruses, contribute to significant disease mortality in HLH. Although T-cell and natural killer cell-driven immune activation and dysregulation are well described, limited data exist on the status of B-cell compartment and humoral immune function in HLH. We noted marked suppression of early B-cell development in patients with active HLH. In vitro B-cell differentiation studies after exposure to HLH-defining cytokines, such as interferon gamma (IFN-γ) and tumor necrosis factor, recapitulated B-cell development arrest. Messenger RNA sequencing of human CD34+ cells exposed to IFN-γ demonstrated changes in genes and pathways affecting B-cell development and maturation. In addition, patients with active HLH exhibited a marked decrease in class-switched memory B (CSMB) cells and a decrease in bone marrow plasmablast/plasma cell compartments. The decrease in CSMB cells was associated with a decrease in circulating T follicular helper (cTfh) cells. Finally, lymph node and spleen evaluation in a patient with HLH revealed absent germinal center formation and hemophagocytosis with associated lymphopenia. Reassuringly, the frequency of CSMB and cTfh improved with the control of T-cell activation. Taken together, in patients with active HLH, these changes in B cells may affect the humoral immune response; however, further immune studies are needed to determine its clinical significance.
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Linfo-Histiocitose Hemofagocítica , Humanos , Linfo-Histiocitose Hemofagocítica/patologia , Citocinas/metabolismo , Interferon gama/genética , Linfócitos T , Células Matadoras NaturaisRESUMO
BACKGROUND: Quantifying T-cell activation is essential for the diagnosis and evaluation of treatment response in various hyperinflammatory and immune regulatory disorders, including hemophagocytic lymphohistiocytosis. Plasma soluble IL-2 receptor (sIL-2R) is a well-established biomarker for evaluating systemic T-cell activation. However, the limited availability of sIL-2R testing could result in delayed diagnosis. Furthermore, high sIL-2R levels may not always reflect T-cell activation. OBJECTIVES: To address these limitations, this study investigated whether cell surface markers of T-cell activation, HLA-DR, and CD38, as assessed by flow cytometry, could be used to quantify systemic T-cell activation in a variety of inflammatory disease states and examine its correlation with sIL-2R levels. METHODS: Results for sIL-2R, CXCL9, and ferritin assays were obtained from patient's medical records. Frequency of HLA-DR+CD38high(hi) T-cells was assessed in different T-cell subsets using flow cytometry. RESULTS: In this study's cohort, activation in total CD8+ T (r = 0.65; P < .0001) and CD4+ (r = 0.42; P < .0001) T-cell subsets significantly correlated with plasma sIL-2R levels. At the disease onset, the frequency of HLA-DR+CD38hi T cells in CD8+ T (r = 0.65, P < .0001) and CD4+ T (r = 0.77; P < .0001) effector memory (TEM) compartments correlated strongly with sIL-2R levels. Evaluation of T-cell activation markers in follow-up samples also revealed a positive correlation for both CD4+ TEM and CD8+ TEM activation with sIL-2R levels; thus, attesting its utility in initial diagnosis and in evaluating treatment response. The frequency of HLA-DR+CD38hi T-cells in the CD8+ TEM compartment also correlated with plasma CXCL9 (r = 0.42; P = .0120) and ferritin levels (r = 0.32; P = .0037). CONCLUSIONS: This study demonstrates that flow cytometry-based direct T-cell activation assessed by HLA-DR+CD38hi T cells accurately quantifies T-cell activation and strongly correlates with sIL-2R levels across a spectrum of hyperinflammatory and immune dysregulation disorders.
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Doenças do Sistema Imunitário , Linfo-Histiocitose Hemofagocítica , Humanos , Linfo-Histiocitose Hemofagocítica/diagnóstico , Linfócitos T CD8-Positivos , Antígenos HLA-DR , Subpopulações de Linfócitos T , Receptores de Interleucina-2 , Ferritinas , Ativação LinfocitáriaRESUMO
The fusion of haemagglutinin-neuraminidase (HN) protein of peste des petits ruminant (PPR) virus with signaling lymphocyte activation molecules (SLAM) host cell receptor consequences the virus entry and multiplication inside the host cell. The use of synthetic SLAM homologous peptides (i.e., molecular decoy for HN protein of PPR virus) may check PPR infection at the preliminary stage. Hence, the predicted SLAM homologous peptides using bioinformatics tools were synthesized by solid phase chemistry with standard Merrifield's 9-fluorenylmethoxycarbonyl (Fmoc) chemistry and were purified by reverse phase high performance liquid chromatography. The secondary structures of synthesized peptides were elucidated by circular dichroism spectroscopy. The in vitro interactions of these peptides were studied through indirect Enzyme Linked Immuno Sorbent Assay (ELISA) and visual surface plasmon UV-visible spectroscopy. The SLAM homologous peptides were able to interact with the peste des petits ruminant virus (PPRV) with varying binding efficiency. The interaction of SLAM homologous peptide with the PPR virus was ascertained by the change in the plasmon color from red wine to purple during visual detection and also by bathochromic shift in absorbance spectra under UV-visible spectrophotometry. The cytotoxic and anti-PPRV effect of these peptides were also evaluated in B95a cell line using PPR virus (Sungri/96). The cytotoxic concentration 50 (CC50 ) value of each peptide was greater than 1000 µg mL-1 . The anti-PPRV efficiency of SLAM-22 was relatively high among SLAM homologous peptides, SLAM-22 at 25 µg mL-1 concentration showed a reduction of more than log10 3 virus titer by priming of B95a cell line while the use of SLAM-15 and Muco-17 at the same concentration dropped virus titer from log10 4.8 to log10 2.5 and log10 3.1 respectively. The concentration of SLAM homologous peptide (25 µg mL-1 ) to exert its anti-PPRV effect was much less than its CC50 level (>1000 µg mL-1 ). Therefore, the synthetic SLAM homologous peptides may prove to be better agents to target PPRV.
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Peste dos Pequenos Ruminantes , Vírus da Peste dos Pequenos Ruminantes , Animais , Vírus da Peste dos Pequenos Ruminantes/metabolismo , Peste dos Pequenos Ruminantes/metabolismo , Linhagem Celular , Proteínas Virais/metabolismo , Peptídeos/farmacologia , Peptídeos/metabolismo , CabrasRESUMO
Magnesium transporter 1 (MAGT1) gene loss-of-function variants lead to X-linked MAGT1 deficiency with increased susceptibility to EBV infection and N-glycosylation defect (XMEN), a condition with a variety of clinical and immunological effects. In addition, MAGT1 deficiency has been classified as a congenital disorder of glycosylation (CDG) due to its unique role in glycosylation of multiple substrates including NKG2D, necessary for viral protection. Due to the predisposition for EBV, this etiology has been linked with hemophagocytic lymphohistiocytosis (HLH), however only limited literature exists. Here we present a complex case with HLH and EBV-driven classic Hodgkin lymphoma (cHL) as the presenting manifestation of underlying immune defect. However, the patient's underlying immunodeficiency was not identified until his second recurrence of Hodgkin disease, recurrent episodes of Herpes Zoster, and after he had undergone autologous hematopoietic stem cell transplant (HSCT) for refractory Hodgkin lymphoma. This rare presentation of HLH and recurrent lymphomas without some of the classical immune deficiency manifestations of MAGT1 deficiency led us to review the literature for similar presentations and to report the evolving spectrum of disease in published literature. Our systematic review showcased that MAGT1 predisposes to multiple viruses (including EBV) and adds risk of viral-driven neoplasia. The roles of MAGT1 in the immune system and glycosylation were highlighted through the multiple organ dysfunction showcased by the previously validated Immune Deficiency and Dysregulation Activity (IDDA2.1) score and CDG-specific Nijmegen Pediatric CDG Rating Scale (NPCRS) score for the patient cohort in the systematic review.
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Infecções por Vírus Epstein-Barr , Doença de Hodgkin , Linfo-Histiocitose Hemofagocítica , Humanos , Masculino , Proteínas de Transporte de Cátions , Infecções por Vírus Epstein-Barr/diagnóstico , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/genética , Transplante de Células-Tronco Hematopoéticas , Herpesvirus Humano 4 , Doença de Hodgkin/diagnóstico , Doença de Hodgkin/genética , Doença de Hodgkin/etiologia , Linfo-Histiocitose Hemofagocítica/diagnóstico , Linfo-Histiocitose Hemofagocítica/etiologia , Linfo-Histiocitose Hemofagocítica/genética , RecidivaRESUMO
Cigarette butts (CBs) have become the most ubiquitous form of anthropogenic litter globally. CBs contain various hazardous chemicals that persist in the environment for longer period. These substances are susceptible to leaching into the environment through waterways. The recent study was aimed to evaluate the effects of disposed CBs on the growth and development of Azolla pinnata, an aquatic plant. It was found that after a span of 6 days, the root length, surface area, number of fronds, and photosynthetic efficacy of plant were considerably diminished on the exposure of CBs (concentrations 0 to 40). The exposure of CBs led to a decrease in the FM, FV/F0, and φP0, in contrast, the φD0 increased in response to CBs concentration. Moreover, ABS/CSm, TR0/CSm, and ET0/CSm displayed a negative correlation with CB-induced chemical stress. The performance indices were also decreased (p-value ≤ 0.05) at the highest concentration of CBs. LD50 and LD90 represent the lethal dose, obtained value for LD50 is 20.30 CBs and LD90 is 35.26 CBs through probit analysis. Our results demonstrate that the CBs cause irreversible damage of photosynthetic machinery in plants and also reflect the efficacy of chlorophyll a fluorescence analysis and JIP test for assessing the toxicity of CBs in plants.
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Fotossíntese , Produtos do Tabaco , Clorofila A , Fotossíntese/fisiologia , EcotoxicologiaRESUMO
CD4(+) interleukin 17 (IL-17)-producing helper T cells (T(H)17 cells) are instrumental in the immune response to pathogens. However, an overactive T(H)17 response results in tissue inflammation and autoimmunity, and therefore it is important to identify the molecular mechanisms that control the development of T(H)17 cells. IL-2 suppresses such development, but how IL-2 production is actively suppressed during T(H)7 differentiation is not understood. Here we report that under T(H)17-polarizing conditions, the transcription factors STAT3 and AhR upregulated the expression of Aiolos, a member of the Ikaros family of transcription factors. Using Aiolos-deficient mice, we demonstrated that Aiolos silenced the Il2 locus, promoting T(H)17 differentiation in vitro and in vivo. Thus, we have identified a module in the transcriptional program of T(H)17 cells that actively limits IL-2 production and promotes their differentiation.
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Interleucina-2/biossíntese , Ativação Linfocitária , Células Th17/metabolismo , Transativadores/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Diferenciação Celular , Células Cultivadas , Colite/imunologia , Regulação da Expressão Gênica , Fator de Transcrição Ikaros , Interferon gama/biossíntese , Interferon gama/imunologia , Interleucina-2/genética , Interleucina-2/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Hidrocarboneto Arílico/metabolismo , Fator de Transcrição STAT3/metabolismo , Células Th17/citologia , Células Th17/imunologia , Transativadores/deficiência , Transativadores/genéticaRESUMO
OBJECTIVE: To determine i) pain phenotypes (PP) in people with early-stage knee osteoarthritis (EKOA); ii) the longitudinal association between the phenotypes and pain worsening at two years. DESIGN: We studied participants with EKOA from the Multicenter Osteoarthritis Study defined as pain intensity ≤3/10, Kellgren and Lawrence grade ≤2, intermittent pain none to sometimes, and no constant pain. Two models of PP were explored. Model A included pressure pain thresholds, temporal summation, conditioned pain modulation, pain catastrophizing, sleep quality, depression, and widespread pain (WSP). In Model B, gait characteristics, quadriceps strength, comorbidities, and magnetic resonance imaging features were added to Model A. Latent Class Analysis was used to create phenotypes, and logistic regression was used to determine their association with pain worsening. RESULTS: 750 individuals (60% females), mean age [standard deviation (SD)]: 60.3 (9.4) were included in Model A and 333 individuals (60% females), mean age (SD): 59.4 (8.1) in Model B. 3-class and 4-class solutions were chosen for Model A and Model B. In Model A, the most "severe" phenotype was dominated by psychosocial factors, WSP, and measures of nervous system sensitization. Similarly in Model B, the Model A phenotype plus gait variables, quadriceps strength, and comorbidities were dominant. Surprisingly, none of the phenotypes in either model had a significant relationship with pain worsening. CONCLUSION: Phenotypes based upon various factors thought to be important for the pain experience were identified in those with EKOA but were not significantly related to pain worsening. These phenotypes require validation with clinically relevant endpoints.
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Dor Crônica , Osteoartrite do Joelho , Feminino , Humanos , Masculino , Osteoartrite do Joelho/complicações , Osteoartrite do Joelho/psicologia , Estudos de Coortes , Limiar da Dor , Fenótipo , Articulação do JoelhoRESUMO
OBJECTIVE: Individuals with chronic pain due to knee osteoarthritis (OA) are insufficiently physically active, and alterations of facilitatory and inhibitory nociceptive signaling are common in this population. Our objective was to examine the association of these alterations in nociceptive signaling with objective accelerometer-based measures of physical activity in a large observational cohort. DESIGN: We used data from the Multicenter Osteoarthritis Study. Measures of peripheral and central pain sensitivity included pressure pain threshold at the knee and mechanical temporal summation at the wrist, respectively. The presence of descending pain inhibition was assessed by conditioned pain modulation (CPM). Physical activity was quantitatively assessed over 7 days using a lower back-worn activity monitor. Summary metrics included steps/day, activity intensity, and sedentary time. Linear regression analyses were used to evaluate the association of pain sensitivity and the presence of descending pain inhibition with physical activity measures. RESULTS: Data from 1873 participants was analyzed (55.9% female, age = 62.8 ± 10.0 years). People having greater peripheral and central sensitivity showed lower step counts. CPM was not significantly related to any of the physical activity measures, and none of the exposures were significantly related to sedentary time. CONCLUSIONS: In this cohort, greater peripheral and central sensitivity were associated with reduced levels of objectively-assessed daily step counts. Further research may investigate ways to modify or treat heightened pain sensitivity as a means to increase physical activity in older adults with knee OA.
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Exercício Físico , Osteoartrite do Joelho , Limiar da Dor , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/fisiopatologia , Osteoartrite do Joelho/complicações , Idoso , Limiar da Dor/fisiologia , Exercício Físico/fisiologia , Medição da Dor , Dor Crônica/fisiopatologia , Acelerometria , Artralgia/fisiopatologiaRESUMO
Pediatric Evans syndrome (pES) is increasingly identified as the presenting manifestation of several inborn errors of immunity. Despite an improved understanding of genetic defects in pES, the underlying immunobiology of pES is poorly defined, and characteristic diagnostic immune parameters are lacking. We describe the immune characteristics of 24 patients with pES and compared them with 22 patients with chronic immune thrombocytopenia (cITP) and 24 healthy controls (HCs). Compared with patients with cITP and HC, patients with pES had increased circulating T-follicular helper cells (cTfh), increased T-cell activation, and decreased naïve CD4+ T cells for age. Despite normal or high immunoglobulin G (IgG) in most pES at presentation, class-switched memory B cells were decreased. Within the cTfh subset, we noted features of postactivation exhaustion with upregulation of several canonical checkpoint inhibitors. T-cell receptor ß chain (TCR-ß) repertoire analysis of cTfh cells revealed increased oligoclonality in patients with pES compared with HCs. Among patients with pES, those without a known gene defect had a similar characteristic immune abnormality as patients with defined genetic defects. Similarly, patients with pES with normal IgG had similar T-cell abnormalities as patients with low IgG. Because genetic defects have been identified in less than half of patients with pES, our findings of similar immune abnormalities across all patients with pES help establish a common characteristic immunopathology in pES, irrespective of the underlying genetic etiology.
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Anemia Hemolítica Autoimune/imunologia , Ativação Linfocitária , Linfócitos T Auxiliares-Indutores/imunologia , Trombocitopenia/imunologia , Adolescente , Adulto , Anemia Hemolítica Autoimune/patologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Púrpura Trombocitopênica Idiopática/imunologia , Púrpura Trombocitopênica Idiopática/patologia , Linfócitos T Auxiliares-Indutores/patologia , Trombocitopenia/patologia , Adulto JovemRESUMO
A unique approach is imperative for the development of drugs aimed at inhibiting various stages of infection, rather than solely focusing on bacterial viability. Among the array of unconventional targets explored for formulating novel antimicrobial medications, blocking the quorum-sensing (QS) system emerges as a highly effective and promising strategy against a variety of pathogenic microbes. In this investigation, we have successfully assessed nine α-aminoamides for their anti-QS activity using Agrobacterium tumefaciensNT1 as a biosensor strain. Among these compounds, three (2, 3and, 4) have been identified as potential anti-QS candidates. Molecular docking studies have further reinforced these findings, indicating that these compounds exhibit favorable pharmacokinetic profiles. Additionally, we have assessed the ligand's stability within the protein's binding pocket using molecular dynamics (MD) simulations and MMGBSA analysis. Further, combination of antiquorum sensing properties with antibiotics viaself-assembly represents a promising approach to enhance antibacterial efficacy, overcome resistance, and mitigate the virulence of bacterial pathogens. The release study also reflects a slow and gradual release of the metronidazole at both pH 6.5 and pH 7.4, avoiding the peaks and troughs associated with more immediate release formulations.
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Agrobacterium tumefaciens , Antibacterianos , Metronidazol , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Percepção de Quorum , Agrobacterium tumefaciens/efeitos dos fármacos , Percepção de Quorum/efeitos dos fármacos , Metronidazol/farmacologia , Metronidazol/química , Antibacterianos/farmacologia , Antibacterianos/química , Testes de Sensibilidade Microbiana , Géis/química , Sinergismo Farmacológico , Liberação Controlada de FármacosRESUMO
Layered Ni-rich oxides (LiNi1-x-yCoxMnyO2) cathode materials are of current interest in high-energy-demanding applications, such as electric vehicles because of high discharge capacity and high intercalation potential. Here, the effect of co-doping a small amount of Ti and Ta on the crystal structure, morphology, and electrochemical properties of high Ni-rich cathode material LiNi0.8Mn0.1Co0.1-x-yTixTayO2 (0.0≤x+y≤0.2) was systematically investigated. This work demonstrates that an optimum level of Ti and Ta doping is beneficial towards enhancing electrochemical performance. The optimal Ti4+ and Ta5+ co-doped cathode LiNi0.8Mn0.1Co0.09Ti0.005Ta0.005O2 exhibits a superior initial discharge capacity of 161.1â mAh g-1 at 1â C, and excellent capacity retention of 87.1 % after 250 cycles, compared to the pristine sample that exhibits only 59.8 % capacity retention. Moreover, the lithium-ion diffusion coefficients for the co-doped cathode after the 3rd and 50th cycles are 9.9×10-10â cm2 s-1 and 9.3×10-10â cm2 s-1 respectively, which is higher than that of the pristine cathode (3.3×10-10â cm2 s-1 and 2.5×10-10â cm2 s-1 respectively). Based on these studies, we conclude that Ti and Ta co-doping enhances structural stability by mitigating irreversible phase transformation, improving Li-ion kinetics by expanding interlayer spacing, and nanosizing primary particles, thereby stabilizing high-nickel cathode materials and significantly enhancing cyclability.
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Probiotic microorganisms have been used for therapeutic purposes for over a century, and recent advances in biotechnology and genetic engineering have opened up new possibilities for developing therapeutic approaches using indigenous probiotic microorganisms. Diseases are often related to metabolic and immunological factors, which play a critical role in their onset. With the help of advanced genetic tools, probiotics can be modified to produce or secrete important therapeutic peptides directly into mucosal sites, increasing their effectiveness. One potential approach to enhancing human health is through the use of designer probiotics, which possess immunogenic characteristics. These genetically engineered probiotics hold promise in providing novel therapeutic options. In addition to their immunogenic properties, designer probiotics can also be equipped with sensors and genetic circuits, enabling them to detect a range of diseases with remarkable precision. Such capabilities may significantly advance disease diagnosis and management. Furthermore, designer probiotics have the potential to be used in diagnostic applications, offering a less invasive and more cost-effective alternative to conventional diagnostic techniques. This review offers an overview of the different functional aspects of the designer probiotics and their effectiveness on different diseases and also, we have emphasized their limitations and future implications. A comprehensive understanding of these functional attributes may pave the way for new avenues of prevention and the development of effective therapies for a range of diseases.
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Probióticos , Humanos , Probióticos/uso terapêutico , Probióticos/metabolismo , Engenharia Genética , Biotecnologia , Redes Reguladoras de GenesRESUMO
Liposomal vesicles tend to fuse and aggregate during lyophilization. To avoid these events, cryoprotectants are added to the dispersion before lyophilization. Herein, we have compared the effect of three commonly used cryoprotectants (mannitol, MTL; trehalose, THL; and ß-cyclodextrin, ß-CD) upon structural characteristics of liposomes. The formulation was prepared using ethanol injection method, and cryoprotectants were tested at three dose levels (2, 6, and 10 mM). We have elucidated their effect on soy lecithin (SL) liposomes formulated with and without cholesterol (CHL). Characterizations were performed using scattering, thermal, and spectroscopic techniques. CHL molecules interacted hydrophobically with the SL bilayer. In spite of triggering a noticeable increase in the hydrodynamic diameter (about 30 nm), CHL promoted the stabilization of vesicles. Hydrogen bonding interactions were verified by the shift in -OH stretching over 3300-3500 cm-1. This manifested in an increased phase transition temperature (Tm) of SL liposomes. Tm increased further upon incorporation of cryoprotectants, particularly with ß-CD. Enthalpic changes were indicative of an affinity interaction between phospholipids and cryoprotectants, regardless of the presence of CHL. ß-CD showed concentration-dependent changes in the energetics of this interaction. The affinity of cryoprotectant-liposome interaction has been ranked as ß-CD â« THL > MNT.
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Lipossomos , Açúcares , Química Farmacêutica , Fosfolipídeos , Colesterol/químicaRESUMO
In spite of the widespread use of alkanols as penetration enhancers, their effect on vesicular formulations remains largely unexplored. These can affect the stability and integrity of the phospholipid bilayers. In this study, we have investigated the interaction of linear (ethanol, butanol, hexanol, octanol) and branched alkanols (t-amylol and t-butanol) with three phospholipids (soya lecithin, SL; soy L-α-phosphatidylcholine, SPC; and 1,2-dipalmitoyl-sn-glycero-3-phosphocholine, DPPC). Thermodynamic and structural aspects of these interactions were studied as a function of the alkanol concentration and chain length. Our interpretations are based on isothermal titration calorimetry (ITC) and dynamic light scattering (DLS) experiments. We observed one-site interactions wherein hydroxyl and acyl groups interacted with the polar and nonpolar regions of the phospholipid, respectively. The stability and structural integrity of bilayers appeared to be dependent upon (a) the hydrocarbon chain length and concentration of alcohols, and (b) the degree of unsaturation in the phospholipid molecule. We found that these interactions triggered a reduction in the enthalpy which was compensated by increased entropy, keeping free energy negative. Drop in enthalpy indicates reversible disordering of the bilayer which enables the diffusion of alcohol without triggering destabilization. Ethanol engaged predominantly with the interface, and it resulted in higher enthalpic changes. Interactions became increasingly unfavorable with longer alcohols - a cutoff point was recorded with hexanol. The overall sequence of membrane disordering capability was recorded as follows: ethanol < butanol < octanol < hexanol. Octanol's larger size restricted its penetration in the bilayer, and hence it caused less enthalpic changes relative to hexanol. This could also be verified from the trends in the area ratio of these vesicles obtained from the DLS data. Branched alkanols displayed a lower binding affinity with the phospholipids relative to their linear counterparts. These data are useful while contemplating the inclusion of short-chain alcohols as penetration enhancers in phospholipid vesicles.
Assuntos
Bicamadas Lipídicas , Fosfolipídeos , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo , Fosfolipídeos/química , Álcoois/química , Termodinâmica , Fluidez de MembranaRESUMO
An eco-friendly facile synthesis of a series of twenty 1-(4/6-substitutedbenzo[d]thiazol-2-yl)-3-(phenyl/substitutedphenyl)indeno[1,2-c]pyrazol-4(1H)-ones 7a-t was achieved by the reaction of 2-(benzoyl/substitutedbenzoyl)-(1H)-indene-1,3(2H)-dione 3a-t and 2-hydrazinyl-4/6-substitutedbenzo[d]thiazole 6a-t in presence of freshly dried ethanol and glacial acetic acid under reflux conditions in good yields. The newly synthesized derivatives were well characterized using different physical and spectral techniques (FTIR, 1H NMR & 13C NMR, and HRMS). All the compounds were subjected to assess their in vitro α-amylase and glucose diffusion inhibitory activity. Amongst them, the compounds 7i and 7l showed better α-amylase inhibitory activity demonstrating IC50 values of 92.99±1.94 µg/mL and 95.41±3.92 µg/mL, respectively in comparison to the standard drug acarbose (IC50 value of 103.60±2.15 µg/mL). The derivatives 7d and 7k exhibited good glucose diffusion inhibition with values of 2.25±1.16 µg/mL and 2.63±1.45 µg/mL, respectively with standard reference acarbose (2.76±0.55 µg/mL). The observed α-amylase inhibitory activity findings were corroborated through molecular docking investigations, particularly for the highly active compounds 7i (binding energy -8.0 kcal/mol) and 7l (binding energy -8.2 kcal/mol) respectively, in comparison to acarbose with a value of binding energy -6.9 kcal/mol for α-amylase.
Assuntos
Acarbose , Glucose , Relação Estrutura-Atividade , Estrutura Molecular , Simulação de Acoplamento Molecular , alfa-Amilases/metabolismo , Benzotiazóis/farmacologia , alfa-Glucosidases/metabolismo , Inibidores de Glicosídeo Hidrolases/farmacologiaRESUMO
BACKGROUND: The landscape of Pseudomonas infective endocarditis (IE) is evolving with the widespread use of cardiac implantable devices and hospital-acquired infections. This systematic review aimed to evaluate the emerging risk factors and outcomes in Pseudomonas IE. METHODS: A literature search was performed in major electronic databases (PubMed, Scopus, and Google Scholar) with appropriate keywords and combinations till November 2023. We recorded data for risk factors, diagnostic and treatment modalities. This study is registered with PROSPERO, CRD42023442807. RESULTS: A total of 218 cases (131 articles) were included. Intravenous drug use (IDUs) and prosthetic valve endocarditis (PVE) were major risk factors for IE (37.6% and 22%). However, the prosthetic valve was the predominant risk factor in the last two decades (23.5%). Paravalvular complications (paravalvular leak, abscess, or pseudoaneurysm) were described in 40 cases (18%), and the vast majority belonged to the aortic valve (70%). The mean time from symptom onset to presentation was 14 days. The incidence of difficult-to-treat resistant (DTR) pseudomonas was 7.4%. Valve replacement was performed in 57.3% of cases. Combination antibiotics were used in most cases (77%), with the aminoglycosides-based combination being the most frequently used (66%). The overall mortality rate was 26.1%. The recurrence rate was 11.2%. Almost half of these patients were IDUs (47%), and most had aortic valve endocarditis (76%). CONCLUSIONS: This review highlights the changing epidemiology of Pseudomonas endocarditis with the emergence of prosthetic valve infections. Acute presentation and associated high mortality are characteristic of Pseudomonas IE and require aggressive diagnostic and therapeutic approach.