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1.
Proteomics ; : e2400022, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39088833

RESUMEN

Single-cell proteomics (SCP) aims to characterize the proteome of individual cells, providing insights into complex biological systems. It reveals subtle differences in distinct cellular populations that bulk proteome analysis may overlook, which is essential for understanding disease mechanisms and developing targeted therapies. Mass spectrometry (MS) methods in SCP allow the identification and quantification of thousands of proteins from individual cells. Two major challenges in SCP are the limited material in single-cell samples necessitating highly sensitive analytical techniques and the efficient processing of samples, as each biological sample requires thousands of single cell measurements. This review discusses MS advancements to mitigate these challenges using data-dependent acquisition (DDA) and data-independent acquisition (DIA). Additionally, we examine the use of short liquid chromatography gradients and sample multiplexing methods that increase the sample throughput and scalability of SCP experiments. We believe these methods will pave the way for improving our understanding of cellular heterogeneity and its implications for systems biology.

2.
Virology ; 598: 110189, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39089051

RESUMEN

Bovine viral diarrhea virus (BVDV) is a widespread pathogen of cattle and other mammals that causes major economic losses in the livestock industry. N4-TSC and 6NO2-TSC are two thiosemicarbazones derived from 1-indanone that exhibit anti-BVDV activity in vitro. These compounds selectively inhibit BVDV and are effective against both cytopathic and non-cytopathic BVDV-1 and BVDV-2 strains. We confirmed that N4-TSC acts at the onset of viral RNA synthesis, as previously reported for 6NO2-TSC. Moreover, resistance selection and characterization showed that N4-TSCR mutants were highly resistant to N4-TSC but remained susceptible to 6NO2-TSC. In contrast, 6NO2-TSCR mutants were resistant to both compounds. Additionally, mutations N264D and A392E were found in the viral RNA-dependent RNA polymerase (RdRp) of N4-TSCR mutants, whereas I261 M was found in 6NO2-TSCR mutants. These mutations lay in a hydrophobic pocket within the fingertips region of BVDV RdRp that has been described as a "hot spot" for BVDV non-nucleoside inhibitors.

3.
Colloids Surf B Biointerfaces ; 243: 114131, 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39094211

RESUMEN

Identifying the antibacterial mechanisms of elemental silver at the nanoscale remains a significant challenge due to the intertwining behaviors between the particles and their released ions. The open question is which of the above factor dominate the antibacterial behaviors when silver nanoparticles (Ag NPs) with different sizes. Considering the high reactivity of Ag NPs, prior research has primarily concentrated on coated particles, which inevitably hinder the release of Ag+ ions due to additional chemical agents. In this study, we synthesized various Ag NPs, both coated and uncoated, using the laser ablation in liquids (LAL) technique. By analyzing both the changes in particle size and Ag+ ions release, the impacts of various Ag NPs on the cellular activity and morphological changes of gram-negative (E. coil) and gram-positive (S. aureus) bacteria were evaluated. Our findings revealed that for uncoated Ag NPs, smaller particles exhibited greater ions release efficiency and enhanced antibacterial efficacy. Specifically, particles approximately 1.5 nm in size released up to 55 % of their Ag+ ions within 4 h, significantly inhibiting bacterial growth. Additionally, larger particles tended to aggregate on the bacterial cell membrane surface, whereas smaller particles were more likely to be internalized by the bacteria. Notably, treatment with smaller Ag NPs led to more pronounced bacterial morphological changes and elevated levels of intracellular reactive oxygen species (ROS). We proposed that the bactericidal activity of Ag NPs stems from the synergistic effect between particle-cell interaction and the ionic silver, which is dependent on the crucial parameter of particle size.

4.
J Virol ; : e0056024, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39087762

RESUMEN

Powassan virus (POWV) is an emergent tick-borne flavivirus that causes fatal encephalitis in the elderly and long-term neurologic sequelae in survivors. How age contributes to severe POWV encephalitis remains an enigma, and no animal models have assessed age-dependent POWV neuropathology. Inoculating C57BL/6 mice with a POWV strain (LI9) currently circulating in Ixodes ticks resulted in age-dependent POWV lethality 10-20 dpi. POWV infection of 50-week-old mice was 82% fatal with lethality sequentially reduced by age to 7.1% in 10-week-old mice. POWV LI9 was neuroinvasive in mice of all ages, causing acute spongiform CNS pathology and reactive gliosis 5-15 dpi that persisted in survivors 30 dpi. High CNS viral loads were found in all mice 10 dpi. However, by 15 dpi, viral loads decreased by 2-4 logs in 10- to 40-week-old mice, while remaining at high levels in 50-week-old mice. Age-dependent differences in CNS viral loads 15 dpi occurred concomitantly with striking changes in CNS cytokine responses. In the CNS of 50-week-old mice, POWV induced Th1-type cytokines (IFNγ, IL-2, IL-12, IL-4, TNFα, IL-6), suggesting a neurodegenerative pro-inflammatory M1 microglial program. By contrast, in 10-week-old mice, POWV-induced Th2-type cytokines (IL-10, TGFß, IL-4) were consistent with a neuroprotective M2 microglial phenotype. These findings correlate age-dependent CNS cytokine responses and viral loads with POWV lethality and suggest potential neuroinflammatory therapeutic targets. Our results establish the age-dependent lethality of POWV in a murine model that mirrors human POWV severity and long-term CNS pathology in the elderly. IMPORTANCE: Powassan virus is an emerging tick-borne flavivirus causing lethal encephalitis in aged individuals. We reveal an age-dependent POWV murine model that mirrors human POWV encephalitis and long-term CNS damage in the elderly. We found that POWV is neuroinvasive and directs reactive gliosis in all age mice, but at acute stages selectively induces pro-inflammatory Th1 cytokine responses in 50-week-old mice and neuroprotective Th2 cytokine responses in 10-week-old mice. Our findings associate CNS viral loads and divergent cytokine responses with age-dependent POWV lethality and survival outcomes. Responses of young mice suggest potential therapeutic targets and approaches for preventing severe POWV encephalitis that may be broadly applicable to other neurodegenerative diseases. Our age-dependent murine POWV model permits analysis of vaccines that prevent POWV lethality, and therapeutics that resolve severe POWV encephalitis.

5.
Virus Res ; 348: 199445, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39089369

RESUMEN

The four serotypes of the dengue virus (DENV) cause a range of diseases ranging from mild fever to severe conditions. Understanding the immunological interactions among the four serotypes is crucial in comprehending the dynamics of serotype shifting during outbreaks in areas where all four serotypes co-circulate. Hence, we evaluated the neutralizing antibody and antibody-dependent enhancement responses against the four DENV serotypes using acute-phase plasma samples collected from 48 laboratory-confirmed dengue patients during a dengue outbreak in Bali, Indonesia in 2022. Employing single-round infectious particles to exclusively investigate immunogenicity to the structural surface proteins of DENV, which are the targets of antibodies, we found that individuals with a probable prior history of DENV-1 infection exhibited increased susceptibility to secondary DENV-3 infection, attributed to cross-reactive antibodies with limited neutralizing activity against DENV-3 (geometric mean 50 % neutralization titer (GMNT50) = 47.6 ± 11.5). This susceptibility was evident in vitro, with a mean fold enhancement of 28.4 ± 33.9. Neutralization titers against DENV-3 were significantly lower compared to other serotypes (DENV-1 GMNT50 = 678.1 ± 9.0; DENV-2 GMNT50 = 210.5 ± 8.7; DENV-4 GMNT50 = 95.14 ± 7.0). We demonstrate that prior immunity to one serotype provides limited cross-protection against the other serotypes, influencing the dominant serotype in subsequent outbreaks. These findings underscore the complexity of dengue immunity and its implications for vaccine design and transmission dynamics in hyperendemic regions.

6.
J Adv Res ; 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39089617

RESUMEN

BACKGROUND: Neutrophilic inflammation, characterized by dysregulated neutrophil activation, triggers a variety of inflammatory responses such as chemotactic infiltration, oxidative bursts, degranulation, neutrophil extracellular traps (NETs) formation, and delayed turnover. This type of inflammation is pivotal in the pathogenesis of acute respiratory distress syndrome (ARDS) and psoriasis. Despite current treatments, managing neutrophil-associated inflammatory symptoms remains a significant challenge. AIM OF REVIEW: This review emphasizes the role of cyclin-dependent kinases (CDKs) in neutrophil activation and inflammation. It aims to highlight the therapeutic potential of repurposing CDK inhibitors to manage neutrophilic inflammation, particularly in ARDS and psoriasis. Additionally, it discusses the necessary precautions for the clinical application of these inhibitors due to potential off-target effects and the need for dose optimization. KEY SCIENTIFIC CONCEPTS OF REVIEW: CDKs regulate key neutrophilic functions, including chemotactic responses, degranulation, NET formation, and apoptosis. Repurposing CDK inhibitors, originally developed for cancer treatment, shows promise in controlling neutrophilic inflammation. Clinical anticancer drugs, palbociclib and ribociclib, have demonstrated efficacy in treating neutrophilic ARDS and psoriasis by targeting off-label pathways, phosphoinositide 3-kinase (PI3K) and phosphodiesterase 4 (PDE4), respectively. While CDK inhibitors offer promising therapeutic benefits, their clinical repurposing requires careful consideration of off-target effects and dose optimization. Further exploration and clinical trials are necessary to ensure their safety and efficacy in treating inflammatory conditions.

7.
Hum Brain Mapp ; 45(11): e26800, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39093044

RESUMEN

White matter (WM) functional activity has been reliably detected through functional magnetic resonance imaging (fMRI). Previous studies have primarily examined WM bundles as unified entities, thereby obscuring the functional heterogeneity inherent within these bundles. Here, for the first time, we investigate the function of sub-bundles of a prototypical visual WM tract-the optic radiation (OR). We use the 7T retinotopy dataset from the Human Connectome Project (HCP) to reconstruct OR and further subdivide the OR into sub-bundles based on the fiber's termination in the primary visual cortex (V1). The population receptive field (pRF) model is then applied to evaluate the retinotopic properties of these sub-bundles, and the consistency of the pRF properties of sub-bundles with those of V1 subfields is evaluated. Furthermore, we utilize the HCP working memory dataset to evaluate the activations of the foveal and peripheral OR sub-bundles, along with LGN and V1 subfields, during 0-back and 2-back tasks. We then evaluate differences in 2bk-0bk contrast between foveal and peripheral sub-bundles (or subfields), and further examine potential relationships between 2bk-0bk contrast and 2-back task d-prime. The results show that the pRF properties of OR sub-bundles exhibit standard retinotopic properties and are typically similar to the properties of V1 subfields. Notably, activations during the 2-back task consistently surpass those under the 0-back task across foveal and peripheral OR sub-bundles, as well as LGN and V1 subfields. The foveal V1 displays significantly higher 2bk-0bk contrast than peripheral V1. The 2-back task d-prime shows strong correlations with 2bk-0bk contrast for foveal and peripheral OR fibers. These findings demonstrate that the blood oxygen level-dependent (BOLD) signals of OR sub-bundles encode high-fidelity visual information, underscoring the feasibility of assessing WM functional activity at the sub-bundle level. Additionally, the study highlights the role of OR in the top-down processes of visual working memory beyond the bottom-up processes for visual information transmission. Conclusively, this study innovatively proposes a novel paradigm for analyzing WM fiber tracts at the individual sub-bundle level and expands understanding of OR function.


Asunto(s)
Conectoma , Imagen por Resonancia Magnética , Memoria a Corto Plazo , Vías Visuales , Humanos , Memoria a Corto Plazo/fisiología , Conectoma/métodos , Vías Visuales/fisiología , Vías Visuales/diagnóstico por imagen , Adulto , Masculino , Femenino , Percepción Visual/fisiología , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/fisiología , Sustancia Blanca/anatomía & histología , Corteza Visual Primaria/fisiología , Corteza Visual Primaria/diagnóstico por imagen , Cuerpos Geniculados/fisiología , Cuerpos Geniculados/diagnóstico por imagen , Adulto Joven , Corteza Visual/fisiología , Corteza Visual/diagnóstico por imagen
8.
Mol Plant ; 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39095993

RESUMEN

Combinatorial interactions between different regulators diversify and enrich the chance of transcriptional regulation in eukaryotic cells. However, a dose-dependent functional switch of homologous transcriptional repressors has rarely been reported. Here, we show that SHY2, an Auxin/Indole-3-Acetic Acid (Aux/IAA) repressor, exhibits a dose-dependent bimodal role in auxin-sensitive root-hair growth and gene transcription in Arabidopsis, whereas other Aux/IAA homologs consistently repress the auxin responses. The corepressor (TOPLESS [TPL])-binding affinity of a bimodal Aux/IAA was lower than that of a consistently repressing Aux/IAA. The switch of a single amino-acid residue in the TPL-binding motif between the bimodal form and the consistently repressing form switched their TPL-binding affinity and transcriptional and biological roles in auxin responses. Based on these data, we propose a model whereby competition between homologous repressors with different corepressor-binding affinities could generate a bimodal output at the transcriptional and developmental levels.

9.
Ecol Lett ; 27(8): e14477, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39096013

RESUMEN

Explaining the maintenance of genetic variation in fitness-related traits within populations is a fundamental challenge in ecology and evolutionary biology. Frequency-dependent selection (FDS) is one mechanism that can maintain such variation, especially when selection favours rare variants (negative FDS). However, our general knowledge about the occurrence of FDS, its strength and direction remain fragmented, limiting general inferences about this important evolutionary process. We systematically reviewed the published literature on FDS and assembled a database of 747 effect sizes from 101 studies to analyse the occurrence, strength, and direction of FDS, and the factors that could explain heterogeneity in FDS. Using a meta-analysis, we found that overall, FDS is more commonly negative, although not significantly when accounting for phylogeny. An analysis of absolute values of effect sizes, however, revealed the widespread occurrence of modest FDS. However, negative FDS was only significant in laboratory experiments and non-significant in mesocosms and field-based studies. Moreover, negative FDS was stronger in studies measuring fecundity and involving resource competition over studies using other fitness components or focused on other ecological interactions. Our study unveils key general patterns of FDS and points in future promising research directions that can help us understand a long-standing fundamental problem in evolutionary biology and its consequences for demography and ecological dynamics.


Asunto(s)
Selección Genética , Evolución Biológica , Variación Genética , Animales , Aptitud Genética , Filogenia
10.
Artículo en Inglés | MEDLINE | ID: mdl-39096472

RESUMEN

Flavonols effectively scavenge the reactive nitrogen species (RNS) and reactive oxygen species (ROS) and act as immune-enhancing, anti-inflammatory, anti-diabetic, and anti-carcinogenic agents. Here, we explored the comparative antioxidant and anti-inflammatory properties of plant-originating flavonols, like quercetin, rutin, and troxerutin against acetylsalicylic acid. Quercetin and rutin showed a high ability to remove active ROS, but troxerutin and acetylsalicylic acid exhibited little such function. In RAW 264.7 cells, quercetin, rutin, and troxerutin did not exhibit cellular toxicity at low concentrations. In addition, quercetin, rutin, and troxerutin considerably (p < 0.05) lowered the protein expression of cyclooxygenase 2 (COX-2) as compared to acetylsalicylic acid in cells inflamed with lipopolysaccharides (LPS). Additionally, in inflamed cells, quercetin and rutin significantly down-regulated the nitrogen oxide (NO) level (p < 0.05) at higher concentrations, whereas Troxerutin did not reduce the NO level. In addition, Troxerutin down-regulated the pro-inflammatory protein markers, such as TNF-α, COX-2, NF-κB, and IL-1ß better than quercetin, rutin, and acetylsalicylic acid. We observed that troxerutin exhibited a significantly greater anti-inflammatory effect than acetylsalicylic acid did. Acetylsalicylic acid did not significantly down-regulated the expression of COX-2 and TNF-α (p < 0.05) compared to troxerutin. Hence, it can be concluded that the down-regulation of NO levels and the expression of COX-2 and TNF-α proteins could be mechanisms of action for the natural compounds quercetin, rutin, and troxerutin in preventing inflammation.

11.
Med Image Anal ; 97: 103290, 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39094462

RESUMEN

The brain exhibits intrinsic dynamics characterized by spontaneous spatiotemporal reorganization of neural activity or metastability, which is associated closely with functional integration and segregation. Compared to dynamic functional connectivity, state-dependent effective connectivity (i.e., dynamic effective connectivity) is more suitable for exploring the metastability as its ability to infer causalities between brain regions. However, methods for state-dependent effective connectivity are scarce and urgently needed. In this study, a novel data-driven computational framework, named NHSMM-MAR-sdNC integrating nonparametric hidden semi-Markov model combined with multivariate autoregressive model and state-dependent new causality, is proposed to investigate the state-dependent effective connectivity. The framework is not constrained by any biological assumptions. Furthermore, state number can be inferred from the observed data directly and the state duration distributions will be estimated explicitly rather than restricted by geometric form, which overcomes limitations of hidden Markov model. Experimental results of synthetic data show that the framework can identify the state number adaptively and the state-dependent causality networks accurately. The dynamics of state-related causality networks are also revealed by the new method on real-world resting-state fMRI data. Our method provides a new data-driven computational framework for identifying state-dependent effective connectivity, which will facilitate the identification and assessment of metastability and itinerant dynamics of the brain.

12.
Cell Physiol Biochem ; 58: 336-360, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39092511

RESUMEN

BACKGROUND/AIMS: Individual resistance to hypoxia is an important feature of the physiological profile of an organism, particularly in relation to lead-induced toxicity. METHODS: Our study focused on evaluating parameters of mitochondrial oxygen consumption, microsomal oxidation, intensity of lipoperoxidation processes and antioxidant defences in the liver of rats with low (LR) and high (HR) resistance to hypoxia to elucidate the mechanisms of action of L-arginine and the NO synthase inhibitor L-NNA before or after exposure to lead nitrate. RESULTS: Our study suggests that the redistribution of oxygen-dependent processes towards mitochondrial processes under the influence of the nitric oxide precursor amino acid L-arginine is an important mechanism for maintaining mitochondrial respiratory chain function during per os lead nitrate exposure (3.6 mg lead nitrate/kg bw per day for 30 days). Animals were given L-arginine at a dose of 600 mg/kg bw (i.p., 30 min) before and after exposure to lead nitrate or the NO synthase inhibitor Nω-nitro-L-arginine (L-NNA) at a dose of 35 mg/kg bw (i.p., 30 min) before and after exposure to lead nitrate. Our experiments demonstrated the efficacy of using lead nitrate to simulate lead-related toxic processes via Pb levels in liver tissue; we demonstrated significantly reduced levels of nitrites and nitrates, i.e. stable metabolites of the nitric oxide system, in both LR and HR animals. The effect of the amino acid L-arginine stabilised the negative effects of lead nitrate exposure in both groups of LR and HR rats. We observed the efficiency of mitochondrial energy supply processes and showed a greater vulnerability of NADH-dependent oxidation during lead nitrate exposure in the liver of HR rats. CONCLUSION: L-arginine initiated the processes of oxidation of NADH-dependent substrates in the LR group, whereas in the HR group this directionality of processes was more effective when the role of the nitric oxide system was reduced (use of L-NNA). Our study of key antioxidant enzyme activities in rat liver tissue during lead nitrate exposure revealed changes in the catalase-peroxidase activity ratio. We found different activities of antioxidant enzymes in the liver tissue of rats treated with lead nitrate and L-arginine or L-NNA, with a significant increase in GPx activity in the LR group when L-arginine was administered both before and after exposure to lead nitrate.


Asunto(s)
Arginina , Hipoxia , Plomo , Nitratos , Nitroarginina , Ratas Wistar , Animales , Arginina/metabolismo , Arginina/farmacología , Nitratos/metabolismo , Masculino , Ratas , Nitroarginina/farmacología , Hipoxia/metabolismo , Plomo/toxicidad , Hígado/metabolismo , Hígado/efectos de los fármacos , Consumo de Oxígeno/efectos de los fármacos , Mitocondrias Hepáticas/metabolismo , Mitocondrias Hepáticas/efectos de los fármacos , Peroxidación de Lípido/efectos de los fármacos , Catalasa/metabolismo
13.
Small ; : e2402796, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39092679

RESUMEN

Carbon dots (CDs) based room temperature phosphorescence (RTP) materials can be prepared via facile procedures and exhibit excellent photostability and biocompatibility. Furthermore, doping of hetero-atoms into CDs can afford multiple triplet levels. The RTP emission generated from the resultant CDs always displays outstanding dynamic behaviors and even can be efficiently excited by visible light. Given this, CDs-based RTP materials not only can be used for anti-counterfeiting but also exhibit great application potential in signage and illumination fields. In this contribution, a type of B, N, and P co-doped CDs are prepared in hectogram scale. Upon excitation by UV lamp and white LED, the obtained CDs emit green and yellow RTP, respectively, the lifetime of which are 851 and 481 ms, respectively. It is found that the luminescence color of the CDs can be further tuned. By controlling the degree of carbonization, the RTP color of the CDs can be facilely tuned from green to orange-red. Based on an energy transfer strategy, the luminescence color can be further tuned to red. Benefited from the dynamic and visible-excited colorful RTP emission, the application of these obtained CDs in anti-counterfeiting, fingerprint collection, and luminescent traffic signage are also explored.

14.
Hemoglobin ; : 1-8, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39092801

RESUMEN

Transfusion-dependent thalassemia (TDT) is a major public health concern in India, requiring regular transfusions for survival. There is also significant morbidity caused by iron overload and transfusion related infections. Novel therapies targeting fetal hemoglobin induction are the need of the hour in resource-poor institutions for patients where transplant is not feasible for various reasons. This single arm, non-randomised prospective trial evaluated the efficacy and safety of a combination of low dose thalidomide and hydroxyurea in TDT along with the impact on quality of life (QoL). It included 41 TDT patients, who failed a reasonable trial of hydroxyurea. Complete response (CR) was defined as transfusion independence and partial response (PR) denoted at least a 50% reduction in transfusion requirement. The rest were defined as non-responders (NR). The mean age of the cohort was 20.78 years (range 12-45 years). There were 13 males and 28 females. Nineteen (46.3%), 7 (17.1%), and 15 (36.6%) patients achieved CR, PR, and no response respectively. The overall response rate (CR + PR) was 63.4%. There was a significant increase in hemoglobin levels with decrement in transfusion burden and ferritin levels. There were no significant adverse reactions. No significant predictors of response were found including amongst genetic modifiers. It improved the health related QoL amongst responders. The combination of thalidomide and hydroxyurea appear safe and effective in the reduction in transfusion requirement of TDT patients. The judicious use of these drugs can improve the quality of life and pave the way for patients not eligible for a stem cell transplant.

15.
Heliyon ; 10(14): e33994, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39108891

RESUMEN

Although the store-operated Ca2+ entry (SOCE) plays a critical role in maintaining Ca2+ homeostasis in vascular endothelial cells (VECs), its role in regulating endothelium-dependent hyperpolarization (EDH)-mediated vasorelaxation is largely unknown. Inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS) are the most common gastrointestinal disorders with no effective cures. The present study applied N,N,N',N'-tetrakis (2-pyridylmethyl)ethylenediamine (TPEN) as a Ca2+ chelator in the endoplasmic reticulum (ER) to study the SOCE/EDH-mediated vasorelaxation of micro-arteries and their involvements in the pathogenesis of IBD and IBS. Human submucosal arterioles and the second-order branch of 6-8 weeks male C57BL/6 mouse mesenteric arterioles were used, and TPEN-induced vasorelaxation was recorded by Danish DMT520A microvascular measuring system. The mice were fed water with 2.5 % dextran sulfate sodium for 7 days to induce mouse model of ulcerative colitis, and water avoidance stress was used to induce mouse model of IBS. The statistical significance of differences in the means of experimental groups was determined using a t-test for two groups or one-way ANOVA for more than two groups. TPEN concentration-dependently induced vasorelaxation of human colonic submucosal arterioles and the second-order branch of murine mesenteric arteries in endothelium-dependent manner. TPEN-induced vasorelaxation was much greater in the arteries pre-constricted by noradrenaline than those by high K+. While TPEN-induced vasorelaxation was unaffected by inhibitors of NO and PGI2, it was significantly inhibited by the selective inhibitors of IKCa and SKCa channels but was potentiated by their activator. Moreover, TPEN-induced vasorelaxation was attenuated by selective inhibitors of NCX, NKA, SOCE, STIM translocation and Orai transportation. Finally, TPEN-induced vasorelaxation via SOCE/EDH was impaired in colitic mice but remained intact in IBS mice. Interestingly, TPEN could rescue vagus neurotransmitter ACh-induced vasorelaxation that was impaired in IBS mice. Therefore, since TPEN-induced SOCE/EDH-mediated vasorelaxation of mesenteric arteries is well-preserved to be able to rescue ACh-induced vasorelaxation impaired in IBS, TPEN has therapeutic potentials for IBS.

16.
Front Oncol ; 14: 1401861, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39109289

RESUMEN

Atypical lipomatous tumors (ALTs) are locally aggressive adipocytic malignancies that frequently occur in middle-aged adults. We report the rare case of an ALT of the thigh that occurred in a 4-year-old girl. Since the tumor was initially diagnosed as a lipoblastoma by incisional biopsy, marginal resection was performed. Histopathological findings of the surgical specimen revealed the proliferation of mature and variously sized adipocytes, as well as ectopic ossification; these features differ from the typical findings of lipoblastoma. Immunohistochemical findings showed nuclear positivity for a murine double minute 2 (MDM2) and cyclin-dependent kinase 4 (CDK4) and negativity for pleomorphic adenoma gene 1 (PLAG1). Fluorescence in situ hybridization showed abnormal amplification of the MDM2 gene. The patient was thus finally diagnosed as having an ALT. No signs of local recurrence or metastasis were noted 1 year postoperatively. This case is instructive in the differential diagnosis of primary adipocytic tumors. Lipoblastomas are the most common adipocytic tumors in children, but if a tumor is located in the deep tissue or imaging findings are not typical, the possibility of ALT should be considered and immunohistochemistry for MDM2 and CDK4 should be added.

17.
J Adv Res ; 2024 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-39103048

RESUMEN

INTRODUCTION: Mitophagy, a selective form of autophagy responsible for maintaining mitochondrial homeostasis, regulates the antiviral immune response and acts as viral replication platforms to facilitate infection with various viruses. However, its precise role in herpes simplex virus 1 (HSV-1) infection and herpes simplex encephalitis (HSE) remains largely unknown. OBJECTIVES: We aimed to investigate the regulation of mitophagy by HSV-1 neurotropic infection and its role in viral encephalitis, and to identify small compounds that regulate mitophagy to affect HSV-1 infection. METHODS: The antiviral effects of compounds were investigated by Western blot, RT-PCR and plaque assay. The changes of Parkin (PRKN)-mediated mitophagy and Nuclear Factor kappa B (NFKB)-mediated neuroinflammation were examined by TEM, RT-qPCR, Western blot and ELISA. The therapeutic effect of taurine or PRKN-overexpression was confirmed in the HSE mouse model by evaluating survival rate, eye damage, neurodegenerative symptoms, immunohistochemistry analysis and histopathology. RESULTS: HSV-1 infection caused the accumulation of damaged mitochondria in neuronal cells and in the brain tissue of HSE mice. Early HSV-1 infection led to mitophagy activation, followed by inhibition in the later viral infection. The HSV-1 proteins ICP34.5 or US11 deregulated the EIF2S1-ATF4 axis to suppress PRKN/Parkin mRNA expression, thereby impeding PRKN-dependent mitophagy. Consequently, inhibition of mitophagy by specific inhibitor midiv-1 promoted HSV-1 infection, whereas mitophagy activation by PRKN overexpression or agonists (CCCP and rotenone) attenuated HSV-1 infection and reduced the NF-κB-mediated neuroinflammation. Moreover, PRKN-overexpressing mice showed enhanced resistance to HSV-1 infection and ameliorated HSE pathogenesis. Furthermore, taurine, a differentially regulated gut microbial metabolite upon HSV-1 infection, acted as a mitophagy activator that transcriptionally promotes PRKN expression to stimulate mitophagy and to limit HSV-1 infection both in vitro and in vivo. CONCLUSION: These results reveal the protective function of mitophagy in HSE pathogenesis and highlight mitophagy activation as a potential antiviral therapeutic strategy for HSV-1-related diseases.

18.
Front Immunol ; 15: 1379023, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39104533

RESUMEN

Antibody-mediated complement-dependent cytotoxicity (CDC) on malignant cells is regulated by several complement control proteins, including the inhibitory complement factor H (fH). fH consists of 20 short consensus repeat elements (SCRs) with specific functional domains. Previous research revealed that the fH-derived SCRs 19-20 (SCR1920) can displace full-length fH on the surface of chronic lymphocytic leukemia (CLL) cells, which sensitizes CLL cells for e.g. CD20-targeting therapeutic monoclonal antibody (mAb) induced CDC. Therefore, we constructed lentiviral vectors for the generation of cell lines that stably produce mAb-SCR-fusion variants starting from the clinically approved parental mAbs rituximab, obinutuzumab and ofatumumab, respectively. Flow-cytometry revealed that the modification of the mAbs by the SCRs does not impair the binding to CD20. Increased in vitro lysis potency compared to their parental mAbs was corroborated by showing specific and dose dependent target cell elimination by CDC when compared to their parental mAbs. Lysis of CLL cells was not affected by the depletion of NK cells, suggesting that antibody-dependent cellular cytotoxicity plays a minor role in this context. Overall, this study emphasizes the crucial role of CDC in the elimination of CLL cells by mAbs and introduces a novel approach for enhancing CDC by directly fusing fH SCR1920 with mAbs.


Asunto(s)
Citotoxicidad Celular Dependiente de Anticuerpos , Antígenos CD20 , Factor H de Complemento , Leucemia Linfocítica Crónica de Células B , Rituximab , Humanos , Antígenos CD20/inmunología , Antígenos CD20/genética , Factor H de Complemento/inmunología , Factor H de Complemento/metabolismo , Factor H de Complemento/genética , Leucemia Linfocítica Crónica de Células B/inmunología , Rituximab/farmacología , Anticuerpos Monoclonales Humanizados/farmacología , Anticuerpos Monoclonales/farmacología , Anticuerpos Monoclonales/inmunología , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/metabolismo , Línea Celular Tumoral
19.
Cell Rep ; : 114468, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39106862

RESUMEN

Engrams, which are cellular substrates of memory traces, have been identified in various brain areas, including the amygdala. While most identified engrams are composed of excitatory, glutamatergic neurons, GABAergic inhibitory engrams have been relatively overlooked. Here, we report the identification of an inhibitory engram in the central lateral amygdala (CeL), a key area for auditory fear conditioning. This engram is primarily composed of GABAergic somatostatin-expressing (SST(+)) and, to a lesser extent, protein kinase C-δ-expressing (PKC-δ(+)) neurons. Fear memory is accompanied by a preferential enhancement of synaptic inhibition onto PKC-δ(+) neurons. Silencing this CeL GABAergic engram disinhibits the activity of targeted extra-amygdaloid areas, selectively increasing the expression of fear. Our findings define the behavioral function of an engram formed exclusively by GABAergic inhibitory neurons in the mammalian brain.

20.
Arch Microbiol ; 206(9): 367, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39105810

RESUMEN

2-methylisoborneol (2-MIB) is an odiferous metabolite mainly produced by cyanobacteria, contributing to taste and odor problems in drinking water. The mechanisms involved in 2-MIB biosynthesis in cyanobacteria are not yet completely understood. This study investigated the effect of light availability and wavelength on growth, 2-MIB synthesis, and related gene expression in Pseudanabaena foetida var. intermedia. A significantly lower 2-MIB production was observed in P. foetida var. intermedia during the dark period of a 12-h photoperiod. Exposure to green light resulted in a significant decrease in 2-MIB production compared to white light and red light. The relative expression levels of 2-MIB-related genes in P. foetida var. intermedia were significantly lower during the dark period of a 12-h photoperiod and when cultured under green light. The expression of 2-MIB-related genes in cyanobacteria appears to be light-dependent. This study suggests that the demand for photopigment synthesis under unfavorable light conditions affects the 2-MIB synthesis in cyanobacteria.


Asunto(s)
Canfanos , Cianobacterias , Luz , Cianobacterias/genética , Cianobacterias/metabolismo , Cianobacterias/efectos de la radiación , Cianobacterias/crecimiento & desarrollo , Canfanos/metabolismo , Fotoperiodo , Regulación Bacteriana de la Expresión Génica , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo
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