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1.
J Infect Dis ; 230(2): 336-345, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-38324907

RESUMEN

Early innate immune responses play an important role in determining the protective outcome of Mycobacterium tuberculosis (Mtb) infection. Nuclear factor κB (NF-κB) signaling in immune cells regulates the expression of key downstream effector molecules that mount early antimycobacterial responses. Using conditional knockout mice, we studied the effect of abrogation of NF-κB signaling in different myeloid cell types and its impact on Mtb infection. Our results show that the absence of IKK2-mediated signaling in all myeloid cells resulted in increased susceptibility to Mtb infection. In contrast, the absence of IKK2-mediated signaling in CD11c+ myeloid cells induced early proinflammatory cytokine responses, enhanced the recruitment of myeloid cells, and mediated early resistance to Mtb. Abrogation of IKK2 in MRP8-expressing neutrophils did not affect disease pathology or Mtb control. Thus, we describe an early immunoregulatory role for NF-κB signaling in CD11c-expressing phagocytes and a later protective role for NF-κB in LysM-expressing cells during Mtb infection.


Asunto(s)
Antígeno CD11c , Ratones Noqueados , Mycobacterium tuberculosis , FN-kappa B , Fagocitos , Transducción de Señal , Tuberculosis , Animales , Mycobacterium tuberculosis/inmunología , FN-kappa B/metabolismo , Fagocitos/inmunología , Fagocitos/metabolismo , Tuberculosis/inmunología , Tuberculosis/microbiología , Ratones , Antígeno CD11c/metabolismo , Quinasa I-kappa B/metabolismo , Quinasa I-kappa B/genética , Ratones Endogámicos C57BL , Inflamación/metabolismo , Inflamación/inmunología , Citocinas/metabolismo , Neutrófilos/inmunología , Neutrófilos/metabolismo , Antígenos CD11
2.
Infect Immun ; 92(4): e0049523, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38451080

RESUMEN

Tuberculosis (TB) caused by Mycobacterium tuberculosis (Mtb) infects up to a quarter of the world's population. Although immune responses can control Mtb infection, 5%-10% of infected individuals can progress to active TB disease (progressors). A myriad of host factors regulate disease progression in TB and a better understanding of immune correlates of protection and disease is pivotal for the development of new therapeutics. Comparison of human whole blood transcriptomic metadata with that of macaque TB progressors and Mtb-infected diversity outbred mice (DO) led to the identification of differentially regulated gene (DEG) signatures, associated with TB progression or control. The current study assessed the function of Phospholipase C epsilon (PLCƐ1), the top downregulated gene across species in TB progressors, using a gene-specific knockout mouse model of Mtb infection and in vitro Mtb-infected bone marrow-derived macrophages. PLCƐ1 gene expression was downregulated in TB progressors across species. PLCε1 deficiency in the mouse model resulted in increased susceptibility to Mtb infection, coincident accumulation of lung myeloid cells, and reduced ability to mount antibacterial responses. However, PLCε1 was not required for the activation and accumulation of T cells in mice. Our results suggest an important early role for PLCƐ1 in shaping innate immune response to TB and may represent a putative target for host-directed therapy.


Asunto(s)
Mycobacterium tuberculosis , Fosfoinositido Fosfolipasa C , Tuberculosis , Humanos , Ratones , Animales , Activación de Macrófagos , Inmunidad Innata
5.
PLoS One ; 19(8): e0306912, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39173049

RESUMEN

This study delves into the complex dynamics of ethical leadership's influence on employees' pro-social rule-breaking behavior, taking into account the mediating role of psychological capital and the moderating effect of moral identity. Using data collected from nursing staff in Pakistani hospitals and analyzed through PLS SEM, the study yielded unexpected results. Contrary to the initial hypotheses, the findings reveal a positive relationship between ethical leadership and employees' pro-social rule-breaking behavior within organizational settings. Furthermore, the study identifies psychological capital as a key mediator in this relationship, while moral identity emerges as a crucial moderator. These results challenge the conventional perception of ethical leadership as an exclusively positive form of leadership and underscore its unintended consequences. Moreover, they underscore the significance of employees' psychological processes and individual differences in unraveling this paradoxical relationship. These results have the potential to reshape how organizations view ethical leadership and consider the unintended outcomes it may generate. Future research can build upon these findings to explore the boundaries and contextual factors that influence the effects of ethical leadership, ultimately contributing to a more comprehensive understanding of leadership dynamics in diverse organizational settings.


Asunto(s)
Liderazgo , Principios Morales , Humanos , Femenino , Masculino , Adulto , Pakistán , Conducta Social , Cultura Organizacional
6.
J Tradit Chin Med ; 44(3): 496-504, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38767633

RESUMEN

OBJECTIVE: To investigate the effects of Hippeastrum hybridum (HH) as a free radical scavenger, and an inhibitor of the two enzymes i-e Alpha-amylase (α-amylase) and acetylcholinesterase (AChE). METHODS: In this study, HH plant was preliminary analyzed for phytochemical screening and then tested for its antioxidant, anti-α-amylase, and anti-AChE efficiency via standard procedures. RESULTS: Phytochemical analysis shows the existence of different compounds; while Coumarins and quinones were absent. The total phenolic, flavonoid, and tannins content were found to be (78.52 ± 0.69) mg GAE/g, (2.01 ± 0.04) mg RUE/g, and (58.12 ± 0.23) mg TAE/g of plant extract respectively. 28.02% ± 0.02% alkaloid and 2.02% ± 0.05% saponins were present in the HH extract. The HH extract showed the anti-oxidant property with IC50 (50% inhibition) of (151.01 ± 0.13) (HH), (79.01 ± 0.04) (Ascorbic acid) for ferric reducing, (91.48 ± 0.13) (HH), (48.02 ± 0.11) (Ascorbic acid) against Ammonium molybdenum, (156.02 ± 0.31) (HH), (52.38 ± 0.21) (Ascorbic acid) against DPPH, 136.01 ± 0.21 (HH), 52.02± 0.31 (Ascorbic acid) against H2O2, and 154.12 ± 0.03 (HH), (40.05 ± 0.15) (Ascorbic acid) µg/mL against ABTS respectively. Statistical analysis indicated that HH caused a competitive type of inhibition of α-amylase (Vmax remained constant and Km increases from 10.65 to 84.37%) while Glucophage caused the un-competitive type of inhibition i-e both Km and Vmax decreased from 40.49 to 69.15% and 38.86 to 69.61% respectively. The Ki, (inhibition constant); KI, (dissociation constant), Km, (Michaelis-Menten constant), and IC50 were found to be 62, 364, 68.1, and 38.08 ± 0.22 for HH and 12, 101.05, 195, 34.01 ± 0.21 for Glucophage. Similarly, HH causes an anon-competitive type of inhibition of AChE i-e Km remains constant while Vmax decreases from 60.5% to 74.1%. The calculated Ki, KI, Km, and IC50 were found to be 32, 36.2, 0.05, and 18.117 ± 0.018. CONCLUSION: From the current results, it is concluded that HH extract contains bioactive compounds, and could be a good alternative to controlling oxidants, Alzheimer's and Type-II diabetic diseases.


Asunto(s)
Acetilcolinesterasa , Antioxidantes , Inhibidores de la Colinesterasa , Extractos Vegetales , alfa-Amilasas , Antioxidantes/química , Antioxidantes/farmacología , alfa-Amilasas/antagonistas & inhibidores , alfa-Amilasas/química , Inhibidores de la Colinesterasa/química , Inhibidores de la Colinesterasa/farmacología , Acetilcolinesterasa/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Humanos , Fitoquímicos/química , Fitoquímicos/farmacología , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología
7.
Cureus ; 16(6): e63300, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39070386

RESUMEN

This systematic analysis aimed to analyze the key patterns and tendencies regarding bystander interventions, emergency medical service (EMS) systems, dispatcher support, regional and temporal differences, and the influence of national efforts on survival rates in out-of-hospital cardiac arrest (OHCA). The studies published between 2010 and 2024 examining outcomes of OHCA, interventions by bystanders, and variables linked to OHCA were included in this research. The inclusion process was done under Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), where publications (n = 24) from various geographical locations, including a wide range of research methodologies, were included for this research. The thematic analysis used for the data analysis shows that bystander cardiopulmonary resuscitation (CPR) enhances the chances of survival. The effectiveness of the EMS system, the assistance offered by dispatchers, and the inclusion of doctors in ambulance services are essential components in the management of OHCA. Regional and temporal variations highlight disparities in resuscitation protocols, emphasizing the need for adaptable approaches. Observations from statewide endeavors emphasize the impact of these activities in fostering a culture of prompt bystander intervention. This systematic review presents a comprehensive analysis of research conducted globally, providing a thorough insight into the variables that influence survival rates in instances of OHCA. The review recognizes the importance of bystander CPR and effective EMS services, while also bringing novel perspectives, such as gender disparities and geographical variations that contribute to the existing body of research. Despite possible variances in the studies and biases, the findings underscore the need for tailored therapies and ongoing research to optimize strategies for controlling OHCA and improving survival rates.

8.
mBio ; 15(4): e0329923, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38407132

RESUMEN

Tuberculosis is the leading cause of death due to an infectious disease worldwide. Innate lymphoid type 3 cells (ILC3s) mediate early protection during Mycobacterium tuberculosis (Mtb) infection. However, the early signaling mechanisms that govern ILC3 activation or recruitment within the lung during Mtb infection are unclear. scRNA-seq analysis of Mtb-infected mouse lung innate lymphoid cells (ILCs) has revealed the presence of different clusters of ILC populations, suggesting heterogeneity. Using mouse models, we show that during Mtb infection, interleukin-1 receptor (IL-1R) signaling on epithelial cells drives ILC3 expansion and regulates ILC3 accumulation in the lung. Furthermore, our data revealed that C-X-C motif chemokine receptor 5 (CXCR5) signaling plays a crucial role in ILC3 recruitment from periphery during Mtb infection. Our study thus establishes the early responses that drive ILC3 accumulation during Mtb infection and points to ILC3s as a potential vaccine target. IMPORTANCE: Tuberculosis is a leading cause of death due to a single infectious agent accounting for 1.6 million deaths each year. In our study, we determined the role of type 3 innate lymphoid cells in early immune events necessary for achieving protection during Mtb infection. Our study reveals distinct clusters of ILC2, ILC3, and ILC3/ILC1-like cells in Mtb infection. Moreover, our study reveal that IL-1R signaling on lung type 2 epithelial cells plays a key role in lung ILC3 accumulation during Mtb infection. CXCR5 on ILC3s is involved in ILC3 homing from periphery during Mtb infection. Thus, our study provides novel insights into the early immune mechanisms governed by innate lymphoid cells that can be targeted for potential vaccine-induced protection.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis , Vacunas , Ratones , Animales , Inmunidad Innata , Linfocitos , Pulmón
9.
Hum Vaccin Immunother ; 20(1): 2302070, 2024 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-38190806

RESUMEN

Tuberculosis (TB), caused by the intracellular pathogen Mycobacterium tuberculosis (Mtb), affects the lungs of infected individuals (pulmonary TB) but can also affect other sites (extrapulmonary TB). The only licensed vaccine Mycobacterium bovis bacillus Calmette-Guerin (BCG) protects infants and young children but exhibits variable efficacy in protecting against adult pulmonary TB. Poor compliance and prolonged treatment regimens associated with the use of chemotherapy has contributed to the development of multidrug-resistant (MDR) and extensively drug-resistant (XDR) Mtb. Thus, there is an urgent need for the design of more effective vaccines against TB. The development of safe and novel adjuvants for human use is critical. In this study, we demonstrate that saponin-based TQL1055 adjuvant when formulated with a TLR4 agonist (PHAD) and Mtb specific immunodominant antigens (ESAT-6 and Ag85B) and delivered intramuscularly in mice, the SA-TB vaccine induced potent lung immune responses. Additionally, the SA-TB vaccine conferred significant protection against Mtb infection, comparable with levels induced by BCG. These findings support the development of a SA-TB vaccine comprising TQL1055, as a novel, safe and effective TB vaccine for potential use in humans.


Asunto(s)
Mycobacterium bovis , Mycobacterium tuberculosis , Saponinas , Vacunas contra la Tuberculosis , Tuberculosis Pulmonar , Adulto , Niño , Lactante , Humanos , Animales , Ratones , Preescolar , Vacuna BCG , Adyuvantes Inmunológicos , Tuberculosis Pulmonar/prevención & control
10.
NPJ Vaccines ; 9(1): 100, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38844494

RESUMEN

Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), is one of the top infectious killers in the world. The only licensed vaccine against TB, Bacille Calmette-Guérin (BCG), provides variable protection against pulmonary TB, especially in adults. Hence, novel TB vaccine approaches are urgently needed. Both Th1 and Th17 responses are necessary for protection against TB, yet effective adjuvants and vaccine delivery systems for inducing robust Th1 and Th17 immunity are lacking. Herein we describe a synthetic Mincle agonist, UM-1098, and a silica nanoparticle delivery system that drives Th1/Th17 responses to Mtb antigens. Stimulation of human peripheral blood mononuclear cells (hPBMCs) with UM-1098 induced high levels of Th17 polarizing cytokines IL-6, IL-1ß, IL-23 as well as IL-12p70, IL-4 and TNF-α in vitro. PBMCs from both C57BL/6 and BALB/c mice responded with a similar cytokine pattern in vitro and in vivo. Importantly, intramuscular (I.M.) vaccination with UM-1098-adjuvanted TB antigen M72 resulted in significantly higher antigen-specific IFN-γ and IL-17A levels in C57BL/6 wt mice than Mincle KO mice. Vaccination of C57BL/6 wt mice with immunodominant Mtb antigens ESAT6/Ag85B or M72 resulted in predominantly Th1 and Th17 responses and induced antigen-specific serum antibodies. Notably, in a virulent Mtb challenge model, vaccination with UM-1098 adjuvanted ESAT6/Ag85B or M72 significantly reduced lung bacterial burden when compared with unvaccinated mice and protection occurred in the absence of pulmonary inflammation. These data demonstrate that the synthetic Mincle agonist UM-1098 induces strong Th1 and Th17 immunity after vaccination with Mtb antigens and provides protection against Mtb infection in mice.

11.
ACS Chem Biol ; 19(6): 1250-1259, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38843544

RESUMEN

Calprotectin, a metal ion-binding protein complex, plays a crucial role in the innate immune system and has gained prominence as a biomarker for various intestinal and systemic inflammatory and infectious diseases, including inflammatory bowel disease (IBD) and tuberculosis (TB). Current clinical testing methods rely on enzyme-linked immunosorbent assays (ELISAs), limiting accessibility and convenience. In this study, we introduce the Fab-Enabled Split-luciferase Calprotectin Assay (FESCA), a novel quantitative method for calprotectin measurement. FESCA utilizes two new fragment antigen binding proteins (Fabs), CP16 and CP17, that bind to different epitopes of the calprotectin complex. These Fabs are fused with split NanoLuc luciferase fragments, enabling the reconstitution of active luciferase upon binding to calprotectin either in solution or in varied immobilized assay formats. FESCA's output luminescence can be measured with standard laboratory equipment as well as consumer-grade cell phone cameras. FESCA can detect physiologically relevant calprotectin levels across various sample types, including serum, plasma, and whole blood. Notably, FESCA can detect abnormally elevated native calprotectin from TB patients. In summary, FESCA presents a convenient, low-cost, and quantitative method for assessing calprotectin levels in various biological samples, with the potential to improve the diagnosis and monitoring of inflammatory diseases, especially in at-home or point-of-care settings.


Asunto(s)
Técnicas Biosensibles , Complejo de Antígeno L1 de Leucocito , Mediciones Luminiscentes , Complejo de Antígeno L1 de Leucocito/análisis , Humanos , Técnicas Biosensibles/métodos , Mediciones Luminiscentes/métodos , Luciferasas/metabolismo , Luciferasas/química , Biomarcadores/análisis , Biomarcadores/sangre , Enfermedades Inflamatorias del Intestino/diagnóstico , Enfermedades Inflamatorias del Intestino/metabolismo , Tuberculosis/diagnóstico , Tuberculosis/sangre , Luminiscencia
12.
J Pain Res ; 17: 2079-2097, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38894862

RESUMEN

Purpose: An early-stage, multi-centre, prospective, randomised control trial with five-year follow-up was approved by Health Research Authority to compare the efficacy of a minimally invasive, laterally implanted interspinous fixation device (IFD) to open direct surgical decompression in treating lumbar spinal stenosis (LSS). Two-year results are presented. Patients and Methods: Forty-eight participants were randomly assigned to IFD or decompression. Primary study endpoints included changes from baseline at 8-weeks, 6, 12 and 24-months follow-ups for leg pain (visual analogue scale, VAS), back pain (VAS), disability (Oswestry Disability Index, ODI), LSS physical function (Zurich Claudication Questionnaire), distance walked in five minutes and number of repetitions of sitting-to-standing in one minute. Secondary study endpoints included patient and clinician global impression of change, adverse events, reoperations, operating parameters, and fusion rate. Results: Both treatment groups demonstrated statistically significant improvements in mean leg pain, back pain, ODI disability, LSS physical function, walking distance and sitting-to-standing repetitions compared to baseline over 24 months. Mean reduction of ODI from baseline levels was between 35% and 56% for IFD (p<0.002), and 49% to 55% for decompression (p<0.001) for all follow-up time points. Mean reduction of IFD group leg pain was between 57% and 78% for all time points (p<0.001), with 72% to 94% of participants having at least 30% reduction of leg pain from 8-weeks through 24-months. Walking distance for the IFD group increased from 66% to 94% and sitting-to-standing repetitions increased from 44% to 64% for all follow-up time points. Blood loss was 88% less in the IFD group (p=0.024) and operating time parameters strongly favoured IFD compared to decompression (p<0.001). An 89% fusion rate was assessed in a subset of IFD participants. There were no intraoperative device issues or re-operations in the IFD group, and only one healed and non-symptomatic spinous process fracture observed within 24 months. Conclusion: Despite a low number of participants in the IFD group, the study demonstrated successful two-year safety and clinical outcomes for the IFD with significant operation-related advantages compared to surgical decompression.

13.
J. venom. anim. toxins incl. trop. dis ; 27: e20200047, 2021. tab, graf
Artículo en Inglés | VETINDEX, LILACS | ID: biblio-1287090

RESUMEN

The venom of the krait (Bungarus sindanus), an Elapidae snake, is highly toxic to humans and contains a great amount of acetylcholinesterase (AChE). The enzyme AChE provokes the hydrolysis of substrate acetylcholine (ACh) in the nervous system and terminates nerve impulse. Different inhibitors inactivate AChE and lead to ACh accumulation and disrupted neurotransmission. Methods: The present study was designed to evaluate the effect of palladium(II) complex as antivenom against krait venom AChE using kinetics methods. Results: Statistical analysis showed that krait venom AChE inhibition decreases with the increase of Pd(II) complex (0.025-0.05 µM) and exerted 61% inhibition against the AChE at a fixed concentration (0.5 mM) of ACh. Kinetic analysis using the Lineweaver Burk plot showed that Pd(II) caused a competitive inhibition. The compound Pd(II) complex binds at the active site of the enzyme. It was observed that K m (Michaelis-Menten constant of AChE-ACh into AChE and product) increased from 0.108 to 0.310 mM (45.74 to 318.35%) and V max remained constant with an increase of Pd(II) complex concentrations. In AChE K Iapp was found to increase from 0.0912 to 0.025 µM (29.82-72.58%) and did not affect the V maxapp with an increase of ACh from (0.05-1 mM). K i (inhibitory constant) was estimated to be 0.029µM for snake venom; while the K m was estimated to be 0.4 mM. The calculated IC50 for Pd(II) complex was found to be 0.043 µM at constant ACh concentration (0.5 mM). Conclusions: The results show that the Pd(II) complex can be deliberated as an inhibitor of AChE.(AU)


Asunto(s)
Animales , Bungarus , Venenos Elapídicos/toxicidad , Biología Sintética , Paladio , Acetilcolinesterasa
14.
J. physiol. biochem ; 71(4): 743-751, dic. 2015.
Artículo en Inglés | IBECS (España) | ID: ibc-145726

RESUMEN

In the present study, we investigated the efficiency of rosmarinic acid (RA) in preventing the alteration of oxidative parameters in the liver and kidney of diabetic rats induced by streptozotocin (STZ). The animals were divided into six groups (n = 8): control, ethanol, RA 10 mg/kg, diabetic, diabetic/ethanol, and diabetic/RA 10 mg/kg. After 3 weeks of treatment, we found that TBARS levels in liver and kidney were significantly increased in the diabetic/saline group and the administration of RA prevented this increase in the liver and kidney (P < 0.05). Diabetes caused a significant decrease in the activity of superoxide dismutase (SOD) and catalase (CAT) in the diabetes/saline group (P < 0.05). However, the treatment with 10 mg/kg RA (antioxidant) prevented this alteration in SOD and CAT activity in the diabetic RA group (P < 0.05). In addition, RA reverses the decrease in ascorbic acid and non-protein-thiol (NPSH) levels in diabetic rats. The treatment with RA also prevented the decrease in the Delta-aminolevulinic acid dehydratase (ALA-D) activity in the liver and kidney of diabetic rats. Furthermore, RA did not have any effect on glycemic levels. These results indicate that RA effectively reduced the oxidative stress induced by STZ, suggesting that RA is a potential candidate for the prevention and treatment of pathological conditions in diabetic models


Asunto(s)
Animales , Ratas , Diabetes Mellitus/tratamiento farmacológico , Estrés Oxidativo , Antioxidantes/farmacocinética , Extractos Vegetales/farmacocinética , Biomarcadores/análisis , Sustancias Protectoras/farmacocinética , Diabetes Mellitus/fisiopatología , Diabetes Mellitus Experimental/fisiopatología
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