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1.
Artículo en Inglés | MEDLINE | ID: mdl-38788898

RESUMEN

BACKGROUND & AIMS: Necrotizing enterocolitis (NEC) is a life-threatening disease affecting mostly the ileum of preemies. Intestinal epithelial cell (IEC) apoptosis contributes to NEC pathogenesis. However, how scattered crypt IEC apoptosis leads to NEC with excessive villus epithelial necrosis remains unclear. METHODS: A novel triple-transgenic mouse model, namely, 3xTg-iAPcIEC (inducible apoptosis phenotype in crypt-IEC), was developed to induce IECs-specific overexpression of Fasl transgene using doxycycline (Dox)-inducible tetO-rtTA system and villin-cre technology. The three days old neonatal 3xTg-iAPcIEC mice and their littermate controls were subcutaneously (s.c.) challenged with a single dose of Dox. Intestinal tissues were processed at different time points to examine scattered crypt IEC apoptosis-mediated NEC development. Gene knockout technology, antibody-mediated cell depletion, and antibiotic-facilitated Gram-positive bacteria depletion were used to study mechanisms. RESULTS: Treatment of 3xTg-iAPcIEC mouse pups with Dox induces scattered crypt IEC apoptosis followed by crypt inflammation and excessive villous necrosis resembling NEC. This progression correlated with elevated Ifng, Rip3, CD8+ T cells, and Gram-positive bacteria in the ileum. Mechanistically, IFN-γ and RIP3-activated signals mediate the effect of scattered crypt IEC apoptosis on the induction of intestinal crypt inflammation and villous necrosis. Meanwhile, pathophysiological events of CD8+ T cell infiltration and dysbiosis with Gram-positive bacteria primarily contribute to excessive villous inflammation and necrosis. Notably, blocking any of these events protects against NEC development in 3xTg-iAPcIEC mouse pups, underlining their central roles in NEC pathogenesis. CONCLUSIONS: Scattered crypt IEC apoptosis induces NEC in mouse pups via IFN-γ, RIP3, CD8+ T cells, and Gram-positive bacteria-mediated comprehensive pathophysiological events. Our findings may advance knowledge in the prevention and treatment of NEC.

2.
bioRxiv ; 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38746153

RESUMEN

Noroviruses are the leading global cause of acute gastroenteritis, responsible for 685 million annual cases. While all age groups are susceptible to noroviruses, children are vulnerable to more severe infections than adults, underscored by 200 million pediatric cases and up to 200,000 deaths in children annually. Understanding the basis for the increased vulnerability of young hosts is critical to developing effective treatments. The pathogenic outcome of any enteric virus infection is governed by a complex interplay between the virus, intestinal microbiota, and host immune factors. A central mediator in these complex relationships are host- and microbiota-derived metabolites. Noroviruses bind a specific class of metabolites, bile acids, which are produced by the host and then modified by commensal bacterial enzymes. Paradoxically, bile acids can have both proviral and antiviral roles during norovirus infections. Considering these opposing effects, the microbiota-regulated balance of the bile acid pool may be a key determinant of the pathogenic outcome of a norovirus infection. The bile acid pool in newborns is unique due to immaturity of host metabolic pathways and developing gut microbiota, which could underlie the vulnerability of these hosts to severe norovirus infections. Supporting this concept, we demonstrate herein that microbiota and their bile acid metabolites protect from severe norovirus diarrhea whereas host-derived bile acids promote disease. Remarkably, we also report that maternal bile acid metabolism determines neonatal susceptibility to norovirus diarrhea during breastfeeding by delivering proviral bile acids to the newborn. Finally, directed targeting of maternal and neonatal bile acid metabolism can protect the neonatal host from norovirus disease. Altogether, these data support the conclusion that metabolic immaturity in newborns and ingestion of proviral maternal metabolites in breast milk are the central determinants of heightened neonatal vulnerability to norovirus disease.

3.
Artículo en Inglés | MEDLINE | ID: mdl-38554082

RESUMEN

Fluoride is widely present in nature, and human exposure to it is generally regarded as inevitable. High levels of fluoride intake induce acute and chronic illnesses. To reduce potential harm to the general public, it is essential to create selective fluoride detectors capable of providing a colorimetric response for naked-eye detection without the need for sophisticated equipment. Here, we report a one-pot synthesis of four different diaminomaleonitrile-derived Schiff base sensors. The terephthalaldehyde adduct provided a strong color change visible to the naked eye at a F- concentration level as low as 2 ppm. From the evaluation against other anions, such as CN-, I-, Br-, Cl-, NO3-, PO43-, OAc-, and HSO4-, the molecular sensor displayed a visible color change exclusively upon exposure to fluoride, underscoring exceptional selectivity. As a key intermediate for understanding the mechanism, HF2- was confirmed by 19F nuclear magnetic resonance. Theoretical calculations suggested a deprotonation-triggered bathochromic shift brought about by the unique electronic structure of the sensor. Furthermore, the simple synthetic protocol from economically accessible materials allowed for the preparation of the compound on a large scale, rendering it a highly practical visual fluoride sensor.

4.
Inorg Chem ; 62(37): 14959-14970, 2023 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-37672483

RESUMEN

Metallogels formed from supramolecular interactions of low-molecular-weight gelators (LMWGs) combine the qualities of heterogeneous catalysts and offer the advantages of multifunctionality owing to the facile installation of desired task-specific moieties on the surface and along the channels of the gels. We discuss the applications of a triazole-based Ni(II) gel-derived xerogel (NiXero) having a high density of Ni(II)-nodes and appended primary amines as a recyclable heterogeneous catalyst for Knoevenagel condensation of aldehyde and malononitrile in water and the solvent-free cycloaddition of CO2 to form a series of cyclic carbonates with near-quantitative conversion of the respective epoxides, with low catalyst loading (0.59 mol %), high catalyst stability, and recyclability. The structural advantages of NiXero, due to the concurrent presence of bifunctional Lewis acid-base sites on the channels, open Ni(II) nodes, Ntriazole, pendant -NH2 and its chemical stability, are conducive to the cooperative heterogeneous catalytic activity under mild conditions. This work emphasizes the effective amalgamation of metals with purpose-built ligand systems for the construction of metallogels and their utility as heterogeneous catalysts for desired organic transformations.

5.
Cureus ; 15(7): e42753, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37654914

RESUMEN

Introduction The knee joint is a complex system containing various hard and soft tissue components necessary for functioning in a coordinated manner. The menisci help to deepen the tibial plateau. Knowledge of the dimension of menisci in the knee joint is of paramount importance in arthroscopic surgery and the management of injuries due to sports or degeneration. The present study aims to describe the morphometric data of the medial meniscus and document the morphometric variation in the medial menisci. Methodology This study was conducted in the department of anatomy in two medical colleges under MGR University by measuring the dimensions of 100 medial menisci taken from 50 formalin-fixed embalmed cadavers. The width and thickness of the medial menisci were measured using digital vernier calipers. The outer and inner circumferences were measured using a measuring tape, non-elastic threads, and metallic pins. The area of the medial meniscus and the tibial plateau was measured by counting the small squares present in the circumference of the menisci drawn over the graph paper. The weight of the medial menisci was measured using the electronic weigh scale. Results The widest part of the medial meniscus was the posterior one-third, and the narrowest part was the anterior one-third. The thickest part was the middle one-third, followed by the anterior one-third. The average inner and outer circumferences of the menisci were 6.25 cm and 10.05 cm, respectively. The medial meniscus covers more than half of the area of the tibial plateau. Conclusion The present study provides a good understanding of the morphometric features of the medial menisci and will be of great help for managing knee joint pathologies and designing prostheses.

6.
Diagnostics (Basel) ; 13(16)2023 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-37627885

RESUMEN

In this study, we determined if B lymphocytosis may serve as a JDM biomarker for disease activity. Children with untreated JDM were divided into two groups based on age-adjusted B cell percentage (determined through flow cytometry): 90 JDM in the normal B cell group and 45 in the high B cell group. We compared through T-testing the age, sex, ethnicity, duration of untreated disease (DUD), disease activity scores for skin (sDAS), muscle (mDAS), total (tDAS), CMAS, and neopterin between these two groups. The patients in the high B cell group had a higher tDAS (p = 0.009), mDAS (p = 0.021), and neopterin (p = 0.0365). Secondary analyses included B cell values over time and BAFF levels in matched patients with JM (juvenile myositis) and concurrent interstitial lung disease (ILD); JM alone and healthy controls Patient B cell percentage and number was significantly higher after 3-6 months of therapy and then significantly lower on completion of therapy (p =< 0.0001). The JM groups had higher BAFF levels than controls 1304 vs. 692 ng/mL (p = 0.0124). This study supports B cell lymphocytosis as a JDM disease-activity biomarker and bolsters the basis for B cell-directed therapies in JDM.

7.
Int J Appl Basic Med Res ; 13(1): 23-28, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37266531

RESUMEN

Background: Saliva has the potential to be used as a noninvasive sample for testing hyperglycemia in diabetes mellitus. Serum 1,5-anhydroglucitol (1,5-AG) decreases with an increase in blood sugar >180 mg/dl. We hypothesized that salivary 1,5-AG can be used to identify blood sugar higher than 180 mg/dl using a novel biochemical method. Aim: This study aimed to develop a novel biochemical method for serum and salivary assessment of 1,5-AG and assess its correlation with postprandial blood sugar (PPBS) >180 mg/dl. Methodology: The study comprised 45 controls (healthy individuals) and 45 cases (type 2 diabetic patients with PPBS >180 mg/dl). Blood and salivary samples were collected according to the study protocol. A new method was developed for the quantification of 1,5-AG in serum and saliva using liquid chromatography-mass spectrometry. Results: The value of serum (mean -22.19 µg/ml and median -22.12 µg/ml) and salivary (mean -0.124 µg/ml and median -0.088 µg/ml) 1,5-AG was higher in healthy individuals compared to corresponding serum (mean -3.89 µg/ml and median -2.52 µg/ml) and salivary (mean -0.025 µg/ml and median - 0.025 µg/ml) levels in diabetics with PPBS >180 mg/dl. In diabetics, a significant negative correlation was noticed with PPBS levels and 1,5-AG levels in serum and saliva. Salivary 1,5-AG level <0.054 µg/ml had an 86.4% sensitivity and 87.2% specificity in predicting a blood sugar value >180 mg/dl. Conclusion: The results of our study suggest that the short-term glycemic marker 1,5-AG can be detected in saliva and can be useful as an adjunct marker in monitoring of glycemic status in diabetic patients.

8.
Chem Sci ; 14(3): 540-549, 2023 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-36741513

RESUMEN

One of the fundamental aims in catalysis research is to understand what makes a certain scaffold perform better as a catalyst than another. For instance, in nature enzymes act as versatile catalysts, providing a starting point for researchers to understand how to achieve superior performance by positioning the substrate close to the catalyst using non-covalent interactions. However, translating this information to a non-biological catalyst is a challenging task. Here, we report a simple and scalable electrostatically tuned phenol (ETP) as an organocatalyst for transfer hydrogenation of N-arenes using the Hantzsch ester as a hydride source. The biomimetic catalyst (1-5 mol%) displays potential catalytic activity to prepare diverse tetrahydroquinoline derivatives with good to excellent conversion under ambient reaction conditions. Kinetic studies reveal that the ETP is 130-fold faster than the uncharged counterpart, towards completion of the reaction. Control experiments and NMR spectroscopic investigations elucidate the role of the charged environment in the catalytic transformation.

9.
Front Immunol ; 14: 1340442, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38259439

RESUMEN

Clinical evidence indicates a connection between gut injuries, infections, inflammation, and an increased susceptibility to systemic inflammation. Nevertheless, the animal models designed to replicate this progression are inadequate, and the fundamental mechanisms are still largely unknown. This research explores the relationship between gut injuries and systemic inflammation using a Dextran Sulfate Sodium (DSS)-induced colonic mucosal injury mouse model. Continuous treatment of adult mice with 4% DSS drinking water yielded a remarkable mortality rate by day 7, alongside intensified gut injury and detectable peripheral inflammation. Moreover, RNAscope in situ hybridization with 16S rRNA probe noted bacterial penetration into deeper colon compartments of the mice following treatment with DSS for 7 days. Histological analysis revealed inflammation in the liver and lung tissues of DSS-treated mice. In addition, we found that DSS-treated mice exhibited elevation of Alanine transaminase (ALT) and Aspartate transaminase (AST) in peripheral blood and pro-inflammatory cytokine levels in the liver. Notably, the DSS-treated mice displayed a dampened metabolic profile, reduced CD45 marker expression, and an increase in apoptosis within the lymphoid organ such as spleen. These findings suggest that high-dose DSS-induced gut injury gives rise to sepsis-like systemic inflammation characterized by multiple organ injury and profound splenocyte apoptosis and dysfunction of CD45+ cells in the spleen, indicating the role of the spleen in the pathogenesis of gut-derived systemic inflammation. Together, the severe colonic mucosal injury model facilitates research into gut damage and associated peripheral immune responses, providing a vital framework for investigating mechanisms related to clinically relevant, gut-derived systemic inflammation.


Asunto(s)
Traumatismo Múltiple , Bazo , Animales , Ratones , ARN Ribosómico 16S , Inflamación , Membrana Mucosa , Hígado
10.
Am J Physiol Gastrointest Liver Physiol ; 323(3): G205-G218, 2022 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-35819158

RESUMEN

Feeding modes influence the gut microbiome, immune system, and intestinal barrier homeostasis in neonates; how feeding modes impact susceptibility to neonatal gastrointestinal (GI) diseases is still uncertain. Here, we investigated the impact of dam feeding (DF) and formula feeding (FF) on features of the gut microbiome and physiological inflammation during the first 2 days of postnatal development and on the susceptibility to intestinal injury related to the inflammatory state in neonatal mouse pups. 16S rRNA sequencing data revealed microbiome changes, lower α-diversity, and a distinct pattern of ß-diversity including expansion of f_Enterobacteriaceae and f_Enterococcaceae in the ileum of FF pups compared with DF pups by postnatal day (P)2. Together with gut dysbiosis, the FF cohort also had greater ileal mucosa physiological inflammatory activity compared with DF pups by P2 but maintained normal histological features. Interestingly, FF but not DF mouse pups developed necrotizing enterocolitis (NEC)-like intestinal injury within 24 h after anti-CD3 mAb treatment, suggesting that FF influences the susceptibility to intestinal injury in neonates. We further found that NEC-like incidence in anti-CD3 mAb-treated FF neonatal pups was attenuated by antibiotic treatment. Collectively, our data suggest that FF predisposes mouse pups to anti-CD3 mAb-induced intestinal injury due to abnormal f_Enterobacteriaceae and f_Enterococcaceae colonization. These findings advance our understanding of FF-associated microbial colonization and intestinal inflammation, which may help inform the development of new therapeutic approaches to GI diseases like NEC in infants.NEW & NOTEWORTHY This report shows that a feeding mode profoundly affects gut colonization in neonatal mice. Furthermore, our results demonstrate that formula feeding predisposes mouse pups to anti-CD3 mAb-induced necrotizing enterocolitis (NEC)-like intestinal injury upon inadequate microbial colonization. The study suggests the role of the combined presence of formula feeding-associated dysbiosis and mucosal inflammation in the pathogenesis of NEC and provides a new mouse model to study this disease.


Asunto(s)
Enterocolitis Necrotizante , Microbioma Gastrointestinal , Animales , Animales Recién Nacidos , Disbiosis , Enterocolitis Necrotizante/tratamiento farmacológico , Humanos , Inflamación/patología , Mucosa Intestinal/patología , Ratones , ARN Ribosómico 16S
11.
Int J Med Sci ; 19(5): 842-857, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35693733

RESUMEN

Background: Complement component 1 Q subcomponent binding protein (C1QBP) plays a vital role in the progression and metabolism of cancer. Studies have shown that xanthine dehydrogenase (XDH)-derived reactive oxygen species (ROS) accelerates tumor growth, and also induces mutations or produces cytotoxic effects concurrently. However, the role of C1QBP in metabolism, oxidative stress, and apoptosis of renal cell carcinoma (RCC) cells have not yet been explored. Methods: Metabolomics assay was applied to investigate the role of C1QBP in RCC metabolism. C1QBP knockdown and overexpression cells were established via lentiviral infection and subjected to apoptosis and ROS assay in vitro. RNA stability assay was applied to characterize the mechanism of C1QBP regulating XDH transcription. In vivo, orthotopic tumor xenografts assay was performed to investigate the role of C1QBP in RCC progression. Results: Metabolomics investigation revealed that C1QBP dramatically diminished the hypoxanthine content in RCC cells. C1QBP promoted the mRNA and protein expression of hypoxanthine catabolic enzyme XDH. Meanwhile, C1QBP may affect XDH transcription by regulating the mRNA level of XDH transcriptional stimulators IL-6, TNF-α, and IFN-γ. Moreover, the expression of C1QBP and XDH was lower in RCC tumors compared with the tumor-associated normal tissues, and their down-regulation was associated with higher Fuhrman grade. C1QBP significantly increased ROS level, apoptosis, and the expression of apoptotic proteins such as cleaved caspase-3 and bax/bcl2 via regulating XDH. Conclusion: C1QBP promotes the catabolism of hypoxanthine and elevates the apoptosis of RCC cells by modulating XDH-mediated ROS generation.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Apoptosis/genética , Carcinoma de Células Renales/patología , Proteínas Portadoras/metabolismo , Humanos , Hipoxantinas , Neoplasias Renales/patología , Proteínas Mitocondriales/genética , ARN Mensajero , Especies Reactivas de Oxígeno/metabolismo , Xantina Deshidrogenasa/genética , Xantina Deshidrogenasa/metabolismo
13.
Cell Cycle ; 20(22): 2413-2427, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34709966

RESUMEN

Among urological tumors, renal cell carcinoma (RCC) is the third-highest mortality rate tumor, and 20%-30% of RCC patients present with metastases at the time of diagnosis. While the treatment of RCC has been improved over the last few years, its mortality stays high. Y-box binding protein 1 (YBX1) is a well-known oncoprotein that has tumor-promoting functions. YBX1 is widely considered to be an attractive therapeutic target in cancer. To develop novel therapeutics to target YBX1, it is of great importance to understand how YBX1 is finely regulated in cancer. Our previous studies showed that YBX1 in RCC cells significantly promoted cell adhesion, migration, and invasion. However, the role of YBX1 in RCC cells apoptosis has not been reported. In this study, we investigated the effect of YBX1 on cell apoptosis and elucidated the mechanisms involved. Results showed that YBX1 regulated RCC cells apoptosis and reactive oxygen species (ROS) generation via Kindlin-2. These findings indicated that YBX1 inhibited RCC cells apoptosis and may serve as a candidate RCC prognostic marker and a potential therapeutic target. Abbreviations: RCC: Renal cell carcinoma; YBX1: Y-box binding protein 1; ROS: Reactive oxygen species; ccRCC: Clear cell renal cell carcinoma; mccRCC: Metastatic clear cell renal cell carcinoma; G3BP1: Ras-GTPase activating protein SH3 domain-binding proteins 1; SPP1: Secreted phosphoprotein 1; NF-κB: Nuclear factor kappa beta; ECM: Extracellular matrix; EMT: Epithelial-mesenchymal transition; PYCR1: Pyrroline-5-carboxylate reductase 1; MEM: Eagle's Minimum Essential Medium; DMEM: Dulbecco's modified Eagle medium; FBS: Fetal bovine serum; PCR: Polymerase chain reaction; shRNA: Short hairpin RNA; siRNA: Small interfering RNA; BSA: Bovine serum albumin; DCFH-DA: 2,7-Dichlorodihydrofluorescein diacetate; FITC: Fluorescein isothiocyanate; PI: Propidium iodide.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Apoptosis/genética , Carcinoma de Células Renales/genética , Carcinoma de Células Renales/metabolismo , Carcinoma de Células Renales/patología , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , ADN Helicasas/metabolismo , Técnicas de Silenciamiento del Gen , Humanos , Neoplasias Renales/genética , Neoplasias Renales/metabolismo , Neoplasias Renales/patología , Proteínas de la Membrana , Proteínas de Neoplasias , Proteínas de Unión a Poli-ADP-Ribosa/metabolismo , ARN Helicasas/metabolismo , Proteínas con Motivos de Reconocimiento de ARN/genética , Proteína 1 de Unión a la Caja Y/genética
14.
Exp Eye Res ; 211: 108749, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34464609

RESUMEN

Infrared thermography provides functional imaging by picturing the temperature pattern of the region imaged. The temperature correlates to the blood flow pattern and is used in the diagnosis of diseases like breast cancer, peripheral vascular disorders, diabetic neuropathy and fever screening. In the present study, the usage of ocular thermography for diagnosis of diabetic retinopathy is explored. Ocular thermograms using infrared imaging camera were obtained for normal subjects (80 volunteers - 40 males and 40 females) age groups 21-30, 31-40, 41-50 and 51-60 years, non-proliferative diabetic retinopathy (NPDR) patients (50 volunteers -25 males and 25 females) and proliferative diabetic retinopathy (PDR) patients (20 volunteers -10 males and 10 females) belonging to age group of 51-60 years. The temperature at various points of interest (POIs) and horizontal temperature profiles were studied. Ocular surface temperature (OST) and effect of eye dilation on OST was studied for control, age matched NPDR and PDR. Statistical analyses were carried out to find the significance of correlation between OST of controls and NPDR and PDR. The global minimum temperature on the ocular surface for controls (21-60 years) was found to be at cornea which is about 34.79 ± 0.68 °C, and maximum at the inner canthus viz. 36.08 ± 0.62 °C. Dilation studies showed an average increase of 0.82 ± 0.13 °C in cornea and 0.75 ± 0.14 °C in conjunctiva and limbus (p < 0.001). The temperature of cornea is around 33.22 ± 0.12 °C and 32.64 ± 0.12 °C for NPDR and PDR patients respectively, in the age group of 51-60 years. OST of NPDR patients was 0.60 ± 0.15 °C lesser than that of age matched normal eyes (p < 0.001) at cornea and limbus regions and 0.71 ± 0.20 °C at inner canthus. The OST of PDR patients was lesser than age matched controls by 1.18 ± 0.12 °C at cornea, 0.9 ± 0.13 °C at inner canthus and 1.0 ± 0.14 °C at other POIs. During dilation studies a positive variation of 0.61 ± 0.12 °C in cornea and 0.48 ± 0.13 °C in conjunctiva and limbus was observed (p < 0.001) in NPDR eyes. Similarly an average increase of 0.62 ± 0.11 °C in cornea and an average increase of 0.47 ± 0.15 °C in conjunctiva and limbus were observed (p < 0.001) in PDR eyes. The OST of NPDR and PDR patients was less compared with age matched counterparts in both pre and post dilation studies. Dilation of eye showed increase in OST for both controls and diabetic retinopathy patients. The degree of increase is less compared with controls. The variation in OST observed during pre and post dilatation studies of diabetic retinopathy patients is a functional marker of pathology, and can be used as a parameter for diagnosis.


Asunto(s)
Temperatura Corporal/fisiología , Retinopatía Diabética/fisiopatología , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Midriáticos/administración & dosificación , Pupila/efectos de los fármacos , Flujo Sanguíneo Regional/fisiología , Termografía , Tropicamida/administración & dosificación , Adulto Joven
15.
Front Immunol ; 12: 679482, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34177923

RESUMEN

Infection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes COVID-19, a disease that involves significant lung tissue damage. How SARS-CoV-2 infection leads to lung injury remains elusive. The open reading frame 8 (ORF8) protein of SARS-CoV-2 (ORF8SARS-CoV-2) is a unique accessory protein, yet little is known about its cellular function. We examined the cellular distribution of ORF8SARS-CoV-2 and its role in the regulation of human lung epithelial cell proliferation and antiviral immunity. Using live imaging and immunofluorescent staining analyses, we found that ectopically expressed ORF8SARS-CoV-2 forms aggregates in the cytosol and nuclear compartments of lung epithelial cells. Using in silico bioinformatic analysis, we found that ORF8SARS-CoV-2 possesses an intrinsic aggregation characteristic at its N-terminal residues 1-18. Cell culture did not reveal any effects of ORF8SARS-CoV-2 expression on lung epithelial cell proliferation and cell cycle progression, suggesting that ORF8SARS-CoV-2 aggregates do not affect these cellular processes. Interestingly, ectopic expression of ORF8SARS-CoV-2 in lung epithelial cells suppressed basal expression of several antiviral molecules, including DHX58, ZBP1, MX1, and MX2. In addition, expression of ORF8SARS-CoV-2 attenuated the induction of antiviral molecules by IFNγ but not by IFNß in lung epithelial cells. Taken together, ORF8SARS-CoV-2 is a unique viral accessory protein that forms aggregates when expressing in lung epithelial cells. It potently inhibits the expression of lung cellular anti-viral proteins at baseline and in response to IFNγ in lung epithelial cells, which may facilitate SARS-CoV-2 escape from the host antiviral innate immune response during early viral infection. In addition, it seems that formation of ORF8SARS-CoV-2 aggregate is independent from the viral infection. Thus, it would be interesting to examine whether any COVID-19 patients exhibit persistent ORF8 SARS-CoV-2 expression after recovering from SARS-CoV-2 infection. If so, the pathogenic effect of prolonged ORF8SARS-CoV-2 expression and its association with post-COVID symptoms warrant investigation in the future.


Asunto(s)
COVID-19/inmunología , Pulmón/patología , Mucosa Respiratoria/fisiología , SARS-CoV-2/fisiología , Proteínas Virales/metabolismo , COVID-19/virología , Regulación de la Expresión Génica , Células HEK293 , Humanos , Inmunidad , Interferón gamma/metabolismo , Espacio Intracelular , Agregación Patológica de Proteínas , Mucosa Respiratoria/virología
16.
Cells ; 10(4)2021 03 25.
Artículo en Inglés | MEDLINE | ID: mdl-33806041

RESUMEN

Milk fat globule-EGF factor 8 (MFG-E8) is a secreted glycoprotein that regulates tissue homeostasis, possesses potent anti-inflammatory properties, and protects against tissue injury. The human pancreas expresses MFG-E8; however, the role of MFG-E8 in the pancreas remains unclear. We examined the expression of MFG-E8 in the pancreas at baseline and during cerulein-induced acute pancreatitis in mice and determined whether MFG-E8 attenuates the progression of pancreatitis, a serious inflammatory condition that can be life-threatening. We administered cerulein to wild-type (WT) and Mfge8 knockout (KO) mice to induce pancreatitis. Immunoblot analysis showed that MFG-E8 is constitutively expressed in the murine pancreas and is increased in mice with cerulein-induced acute pancreatitis. In situ hybridization revealed that ductal epithelial cells in the mouse pancreas express Mfge8 transcripts at baseline. During pancreatitis, Mfge8 transcripts were abundantly expressed in acinar cells and endothelial cells in addition to ductal epithelial cells. Knocking out Mfge8 in mice exacerbated the severity of cerulein-induced acute pancreatitis and delayed its resolution. In contrast, administration of recombinant MFG-E8 attenuated cerulein-induced acute pancreatitis and promoted repair of pancreatic injury in Mfge8 KO mice. Taken together, our study suggests that MFG-E8 protects the pancreas against inflammatory injury and promotes pancreatic tissue repair. MFG-E8 may represent a novel therapeutic target in acute pancreatitis.


Asunto(s)
Antígenos de Superficie/metabolismo , Proteínas de la Leche/metabolismo , Pancreatitis/patología , Células Acinares/metabolismo , Células Acinares/patología , Animales , Ceruletida , Ratones Endogámicos C57BL , Ratones Noqueados , Páncreas Exocrino/metabolismo , Páncreas Exocrino/patología , Pancreatitis/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Proteínas Recombinantes/metabolismo , Índice de Severidad de la Enfermedad
17.
RSC Adv ; 11(21): 12808-12814, 2021 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-35423816

RESUMEN

Controlling the product selectivity of a ring-opening hydrolysis reaction remains a great challenge with mineral acids and to an extent with homogeneous catalysts. In addition, even trace amounts of metal impurities in a bioactive product hinder the reaction progress. This has necessitated the development of robust and metal-free catalysts to offer an alternative sustainable route. We report a nitrogen-rich sulfonated carbon as a catalyst derived from an inexpensive precursor for the synthesis of bioactive vicinal diols of spiro-oxindole derivatives. The well-characterized catalyst shows wide generality with different electronic and steric substituents in the substrates under mild reaction conditions. Hot filtration test confirms no leaching of the acid moiety and the catalyst could be reused for four cycles with retention of activities.

18.
ChemSusChem ; 14(3): 824-841, 2021 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-33369102

RESUMEN

Stoichiometric carbon dioxide reduction to highly reduced C1 molecules, such as formic acid (2e- ), formaldehyde (4e- ), methanol (6e- ) or even most-reduced methane (8e- ), has been successfully achieved by using organosilanes, organoboranes, and frustrated Lewis Pairs (FLPs) in the presence of suitable catalyst. The development of renewable organohydride compounds could be the best alternative in this regard as they have shown promise for the transfer of hydride directly to CO2 . Reduction of CO2 by two electrons and two protons to afford formic acid by using renewable organohydride molecules has recently been investigated by various groups. However, catalytic CO2 reduction to ≥2e- -reduced products by using renewable organohydride-based molecules has rarely been explored. This Minireview summarizes important findings in this regard, encompassing both stoichiometric and catalytic CO2 reduction.

19.
Trop Doct ; 51(1): 111-114, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33108966

RESUMEN

Isolated pleural effusion is a rare manifestation of filariasis that mimics tuberculosis, especially in endemic regions. We describe a case of lymphocytic and exudative pleural effusion showing microfilaria on pleural fluid cytology. A retrospective review of all cases of filarial pleural effusion reported after 2000 was conducted to evaluate the association between filariasis and pleural effusion as well as to screen the features that can help in accurate detection of these patients. The analysis suggested a causal association between the parasite and the development of pleural effusion with a high sensitivity of pleural fluid cytology for diagnosis.


Asunto(s)
Filariasis/parasitología , Microfilarias/aislamiento & purificación , Derrame Pleural/parasitología , Adulto , Animales , Diagnóstico Diferencial , Filariasis/diagnóstico , Filariasis/patología , Humanos , Masculino , Derrame Pleural/diagnóstico , Derrame Pleural/patología , Estudios Retrospectivos , Tuberculosis/diagnóstico
20.
ACS Omega ; 5(25): 14890-14899, 2020 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-32637763

RESUMEN

The construction of sophisticated molecular architectures from chemical subunits requires careful selection of the spacers, precise synthetic strategies, and substantial efforts. Here, we report a series of binuclear double-stranded helicates synthesized from different combinations of pyridyl hydrazone-based multidentate ligands (H2 1, H2 2, H2 3) by increasing the methylene spacer and transition metals (Co, Ni, and Zn). The ligands H2 1 (N'1,N'3-bis((E)-pyridin-2-ylmethylene)malonohydrazide), H2 2 (N'1,N'4-bis((E)-pyridin-2-ylmethylene)succinohydrazide), and H2 3 (N'1,N'5-bis((E)-pyridin-2-ylmethylene)glutarohydrazide) and their respective complexes with Co, Ni, and Zn were obtained. Single-crystal X-ray diffraction studies of these binuclear metallohelicates confirm the double-stranded helical structure of the complexes derived from H2 2. The set of helicates Co-1, Co-2, and Co-3; Ni-1, Ni-2, and Ni-3; and Zn-1, Zn-2, and Zn-3 were investigated for its catalytic activity in the cyclic carbonate formation reaction. Intriguingly, among the synthesized catalyst, Co-1 was found to be better in terms of conversions with the calculated TOF (turnover frequency) of 128/h. The catalytic performance was significantly improved by adding 0.2 mmol of tetrabutylammonium bromide by achieving 76% conversion in 30 min, with the observed TOF of 15,934 h-1/molecule and 7967 h-1/Co center. The results obtained herein show that the double-stranded helicates are effective catalysts for converting both terminal and non-terminal epoxides into their corresponding cyclic carbonates. The striking feature of this catalytic protocol lies in demonstrating the catalytic activity for the conversion of diol to cyclic carbonate, and the detailed kinetic experiments tempted us to propose a tentative reaction mechanism for this conversion.

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