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1.
Rapid Commun Mass Spectrom ; 38(7): e9712, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38351666

RESUMEN

RATIONALE: Azelastine HCl is a second-generation H1 -receptor antagonist approved by the US Food and Drug Administration (US FDA) for treating seasonal allergic rhinitis and non-allergic vasomotor rhinitis. This study encompasses the validation of a liquid chromatography-ultra violet photo diode array (LC-UV/PDA) method for the drug and its extension to liquid chromatography/quadrupole time-of-flight mass spectrometry (LC-Q/TOF-MS) studies for identification and characterization of various stress degradation products of the drug. METHODS: Stress degradation of azelastine HCl was undertaken under the International Council for Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) prescribed conditions of hydrolytic, photolytic, oxidative, and thermal stress. The degraded drug solutions were analyzed using Ultra Performance Liquid Chromatography (UPLC) employing a C18 (100 × 4.6 mm; 2.6 µ, Kinetex) column by isocratic elution. Detection wavelength was 241 nm. The degradation products were identified and characterized using UPLC-MS/TOF studies, and an attempt was made to isolate one of the degradation products by solvent extraction. RESULTS: The drug was found to significantly degrade under acidic/alkaline/neutral photolytic, oxidative, and alkaline hydrolytic conditions. Six degradation products (I-VI) were identified through LC-Q/TOF-MS studies that were adequately resolved from the drug with the developed UPLC method. All degradation products (I-VI) were ionized in the total ion chromatogram (TIC) in the LC-MS studies, and these were identified and characterized, and the degradation pathway of the drug was postulated. One of the oxidation products isolated from the degraded drug solution was characterized through differential scanning calorimetry, Fourier-transform infrared spectroscopy, and nuclear magnetic resonance spectral data. CONCLUSIONS: Six degradation products generated from stress degradation studies on azelastine HCl were adequately resolved through LC-UV/PDA studies followed by method validation. These were successfully identified and characterized through LC-Q/TOF-MS studies, and the degradation pathways for the generation of these products from the drug have been postulated.


Asunto(s)
Ftalazinas , Espectrometría de Masas en Tándem , Humanos , Cromatografía Liquida/métodos , Espectrometría de Masas en Tándem/métodos , Cromatografía Líquida con Espectrometría de Masas , Preparaciones Farmacéuticas/análisis , Estabilidad de Medicamentos , Hidrólisis , Oxidación-Reducción , Cromatografía Líquida de Alta Presión/métodos , Fotólisis
2.
Pediatr Res ; 93(4): 818-826, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-35778498

RESUMEN

BACKGROUND: Antibiotics are commonly used in human neonates, but their impact on neonatal T cell immunity remains poorly understood. The aim of this study was to investigate the impact of the antibiotic piperacillin with the beta-lactamase inhibitor tazobactam on neonatal CD4+ and CD8+ T cell responses to Streptococcus pneumoniae. METHODS: Splenic and lung cells were isolated from the neonatal mice receiving piperacillin and tazobactam or saline (sham) and cultured with S. pneumoniae to analyze T cell cytokine production by ELISA and flow cytometry. RESULTS: Antibiotic exposure to neonatal mice resulted in reduced numbers of CD4+/CD8+ T cells in the spleen and lungs compared to control mice. Upon in vitro stimulation with S. pneumoniae, splenocytes and lung cells from antibiotic-exposed mice produced lower levels of IFN-γ (Th1)/IL-17A (Th17) and IL-17A cytokines, respectively. Flow cytometric analysis revealed that S. pneumoniae-stimulated splenic CD4+ T cells from antibiotic-exposed mice expressed decreased levels of IFN-γ and IL-17A compared to control mice, whereas lung CD4+ T cells produced lower levels of IL-17A. However, no significant difference was observed for IL-4 (Th2) production. CONCLUSIONS: Neonatal mice exposure to piperacillin and tazobactam reduces the number of CD4+ and CD8+ T cells, and suppresses Th1 and Th17, but not Th2, responses to S. pneumoniae. IMPACT: Exposure of neonatal mice with a combination of piperacillin and tazobactam reduces CD4+/CD8+ T cells in the spleen and lungs. Antibiotic exposure suppresses neonatal Th1 and Th17, but not Th2, responses to Streptococcus pneumoniae. Our findings may have important implications for developing better therapeutic strategies in the neonatal intensive care unit.


Asunto(s)
Antibacterianos , Interleucina-17 , Humanos , Animales , Ratones , Animales Recién Nacidos , Antibacterianos/farmacología , Citocinas , Células Th17 , Streptococcus pneumoniae , Piperacilina/farmacología , Tazobactam/farmacología , Células TH1
3.
J Immunol ; 206(6): 1251-1265, 2021 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-33504621

RESUMEN

Recent studies have identified semaphorin 3E (Sema3E) as a novel mediator of immune responses. However, its function in immunity to infection has yet to be investigated. Using a mouse model of chlamydial lung infection, we show that Sema3E plays a significant role in the host immune response to the infection. We found that Sema3E is induced in the lung after chlamydial infection, and Sema3E deficiency has a detrimental impact on disease course, dendritic cell (DC) function, and T cell responses. Specifically, we found that Sema3E knockout (KO) mice exhibited higher bacterial burden, severe body weight loss, and pathological changes after Chlamydia muridarum lung infection compared with wild-type (WT) mice. The severity of disease in Sema3E KO mice was correlated with reduced Th1/Th17 cytokine responses, increased Th2 response, altered Ab response, and a higher number of regulatory CD4 T cells. Moreover, DCs isolated from Sema3E KO mice showed lower surface expression of costimulatory molecules and production of IL-12, but higher expression of PD-L1, PD-L2, and IL-10 production. Functional DC-T cell coculture studies revealed that DCs from infected Sema3E KO mice failed to induce Th1 and Th17 cell responses compared with DCs from infected WT mice. Upon adoptive transfer, mice receiving DCs from Sema3E KO mice, unlike those receiving DCs from WT mice, were not protected against challenge infection. In conclusion, our data evidenced that Sema3E acts as a critical factor for protective immunity against intracellular bacterial infection by modulating DC functions and T cell subsets.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Infecciones por Chlamydia/inmunología , Células Dendríticas/inmunología , Semaforinas/metabolismo , Subgrupos de Linfocitos T/inmunología , Traslado Adoptivo , Animales , Linfocitos T CD4-Positivos/metabolismo , Infecciones por Chlamydia/microbiología , Infecciones por Chlamydia/patología , Chlamydia muridarum/inmunología , Técnicas de Cocultivo , Células Dendríticas/trasplante , Modelos Animales de Enfermedad , Humanos , Pulmón/inmunología , Pulmón/microbiología , Pulmón/patología , Ratones , Ratones Noqueados , Semaforinas/genética , Índice de Severidad de la Enfermedad , Subgrupos de Linfocitos T/metabolismo
4.
Med J Armed Forces India ; 78(3): 249-254, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35855721

RESUMEN

Quality Laboratory services with a widespread reach is the core of a healthcare system of the country. Diagnostic services at all levels requires technical expertise of different laboratory specialists. However the presence of all specialist together in one setup is always not possible due to limited number of trained manpower. Even today, diagnostic laboratory services remain unsupervised. To void this gap, All India Institute of Medical Sciences (AIIMS) New Delhi, in 1988, opened up the patient-centric department of Laboratory Medicine with a centralised specimen collection centre and a core laboratory performing the majority of the routine laboratory investigations, offering a one-window solution to both patients and clinicians. In 1997, a three-year postgraduate Masters degree (MD) in Laboratory Medicine was started. This medical specialty encompasses the art of test selection, test operation, and test interpretation to manage patients. It aligns with the recent technological advancement of automation and advanced instrumentation that are breaking boundaries of the traditional medical laboratories of pathology, biochemistry, and microbiology. This postgraduate model ensures that the laboratory services are accessible, affordable, and available to both patients and clinicians without compromising quality care. Laboratory Medicine is emerging as an answer to one of the several inadequacies and pitfalls of the Indian health system.

5.
Biotechnol Bioeng ; 118(6): 2380-2385, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33459346

RESUMEN

Magnetoelastic (ME) sensors, which can be remotely activated via magnetic fields, are an excellent choice for wireless monitoring of biological parameters due to their ability to be scaled into different sizes and have their surface functionalized for chemical or biological sensing. In this study, we present the application of a commercially available ME material (Metglas 2826 MB) to develop a sensor system that can monitor the attachment of anchorage-dependent mammalian cells in two-dimensional in vitro cell cultures. Results obtained with the developed sensors and detection system correlated with microscopic image analysis of cell quantification, which showed a linear relationship between the sensor response and attached fibroblast cells on the sensor surface. It was also revealed that the developed ME sensor system is capable of providing temporal profiles of cell growth corresponding to different stages of cell attachment and proliferation in real-time.


Asunto(s)
Técnicas de Cultivo de Célula , Proliferación Celular , Magnetismo , Animales , Adhesión Celular , Línea Celular , Diseño de Equipo , Fibroblastos/citología , Ratones
6.
Cell Immunol ; 353: 104132, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32446031

RESUMEN

Protective immune response to chlamydial infection is largely dependent on cell-mediated immune responses with IFN-γ production. Recent studies have shown the critical role of NK cells in bridging innate and adaptive immune responses. In this study, we investigated the effect of NK cells on T cell responses during Chlamydophila pneumoniae (Cpn) lung infection. The results showed that NK cells play a protective role in Cpn infection and influence T cell immunity largely though modulating dendritic cells (DCs) function. Specifically, we found that NK depletion significantly impaired type 1 T cell responses, but enhanced FOXP3+Treg cells and IL-10-producing CD4+T cells. The alteration of T cell responses was associated with more disease severity and higher chlamydial growth in the lung. Further analysis of DC phenotype and cytokine profile found that DCs from NK cell-depleted mice expressed lower levels of co-stimulatory molecules and produced higher levels of IL-10 than those from control IgG-treated mice. More importantly, the adoptive transfer of DCs from NK cell-depleted mice induced a much lower degree of type 1 T cell responses but a higher amount of FOXP3+ Treg cells and IL-10-producing CD4+T cells in the recipient mice than DCs from IgG-treated mice. In contrast to the strong protective effect observed in recipients of DCs from IgG-treated mice, the recipients of DCs from NK cell-depleted mice failed to be protected against Cpn infection. The data suggest that NK cells play a critical role in coordinating innate and adaptive immunity in Cpn lung infection by modulating the DC function to influence T cell responses.


Asunto(s)
Infecciones por Chlamydophila/inmunología , Chlamydophila pneumoniae/inmunología , Células Asesinas Naturales/inmunología , Traslado Adoptivo , Animales , Chlamydophila pneumoniae/metabolismo , Chlamydophila pneumoniae/patogenicidad , Citocinas/metabolismo , Células Dendríticas/inmunología , Inmunidad Celular/inmunología , Células Asesinas Naturales/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Células T Asesinas Naturales/inmunología , Neumonía Bacteriana/inmunología
7.
Appl Environ Microbiol ; 85(6)2019 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-30683742

RESUMEN

Streptococcus pneumoniae is a bacterial pathogen that causes various diseases of public health concern worldwide. Current pneumococcal vaccines target the capsular polysaccharide surrounding the cells. However, only up to 13 of more than 90 pneumococcal capsular serotypes are represented in the current conjugate vaccines. In this study, we used two experimental approaches to evaluate the potential of Streptococcus mitis, a commensal that exhibits immune cross-reactivity with S. pneumoniae, to confer protective immunity to S. pneumoniae lung infection in mice. First, we assessed the immune response and protective effect of wild-type S. mitis against lung infection by S. pneumoniae strains D39 (serotype 2) and TIGR4 (serotype 4). Second, we examined the ability of an S. mitis mutant expressing the S. pneumoniae type 4 capsule (S. mitis TIGR4cps) to elicit focused protection against S. pneumoniae TIGR4. Our results showed that intranasal immunization of mice with S. mitis produced significantly higher levels of serum IgG and IgA antibodies reactive to both S. mitis and S. pneumoniae, as well as enhanced production of interleukin 17A (IL-17A), but not gamma interferon (IFN-γ) and IL-4, compared with control mice. The immunization resulted in a reduced bacterial load in respiratory tissues following lung infection with S. pneumoniae TIGR4 or D39 compared with control mice. With S. mitis TIGR4cps, protection upon challenge with S. pneumoniae TIGR4 was superior. Thus, these findings show the potential of S. mitis to elicit natural serotype-independent protection against two pneumococcal serotypes and to provide the benefits of the well-recognized protective effect of capsule-targeting vaccines.IMPORTANCEStreptococcus pneumoniae causes various diseases worldwide. Current pneumococcal vaccines protect against a limited number of more than 90 pneumococcal serotypes, accentuating the urgent need to develop novel prophylactic strategies. S. pneumoniae and the commensal Streptococcus mitis share immunogenic characteristics that make S. mitis an attractive vaccine candidate against S. pneumoniae In this study, we evaluated the potential of S. mitis and its mutant expressing pneumococcal capsule type 4 (S. mitis TIGR4cps) to induce protection against S. pneumoniae lung infection in mice. Our findings show that intranasal vaccination with S. mitis protects against S. pneumoniae strains D39 (serotype 2) and TIGR4 (serotype 4) in a serotype-independent fashion, which is associated with enhanced antibody and T cell responses. Furthermore, S. mitis TIGR4cps conferred additional protection against S. pneumoniae TIGR4, but not against D39. The findings highlight the potential of S. mitis to generate protection that combines both serotype-independent and serotype-specific responses.


Asunto(s)
Infecciones Neumocócicas/prevención & control , Vacunas Neumococicas/administración & dosificación , Streptococcus pneumoniae/inmunología , Administración Intranasal , Animales , Anticuerpos Antibacterianos/inmunología , Femenino , Humanos , Inmunización , Interferón gamma/genética , Interferón gamma/inmunología , Interleucina-17/genética , Interleucina-17/inmunología , Pulmón/inmunología , Pulmón/microbiología , Ratones , Infecciones Neumocócicas/inmunología , Infecciones Neumocócicas/microbiología , Vacunas Neumococicas/inmunología , Serogrupo , Streptococcus pneumoniae/clasificación , Streptococcus pneumoniae/genética , Linfocitos T/inmunología
8.
BMC Neurosci ; 19(1): 43, 2018 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-30029619

RESUMEN

BACKGROUND: Light exposure induces oxidative stress, which contributes to ocular diseases of aging. Blue light provides a model for light-induced oxidative stress, lipid peroxidation and retinal degeneration in Drosophila melanogaster. In contrast to mature adults, which undergo retinal degeneration when exposed to prolonged blue light, newly-eclosed flies are resistant to blue light-induced retinal degeneration. Here, we sought to characterize the gene expression programs induced by blue light in flies of different ages to identify neuroprotective pathways utilized by photoreceptors to cope with light-induced oxidative stress. RESULTS: To identify gene expression changes induced by blue light exposure, we profiled the nuclear transcriptome of Drosophila photoreceptors from one- and six-day-old flies exposed to blue light and compared these with dark controls. Flies were exposed to 3 h blue light, which increases levels of reactive oxygen species but does not cause retinal degeneration. We identified substantial gene expression changes in response to blue light only in six-day-old flies. In six-day-old flies, blue light induced a neuroprotective gene expression program that included upregulation of stress response pathways and downregulation of genes involved in light response, calcium influx and ion transport. An intact phototransduction pathway and calcium influx were required for upregulation, but not downregulation, of genes in response to blue light, suggesting that distinct pathways mediate the blue light-associated transcriptional response. CONCLUSION: Our data demonstrate that under phototoxic conditions, Drosophila photoreceptors upregulate stress response pathways and simultaneously, downregulate expression of phototransduction components, ion transporters, and calcium channels. Together, this gene expression program both counteracts the calcium influx resulting from prolonged light exposure, and ameliorates the oxidative stress resulting from this calcium influx. Thus, six-day-old flies can withstand up to 3 h blue light exposure without undergoing retinal degeneration. Developmental transitions during the first week of adult Drosophila life lead to an altered gene expression program in photoreceptors that includes reduced expression of genes that maintain redox and calcium homeostasis, reducing the capacity of six-day-old flies to cope with longer periods (8 h) of light exposure. Together, these data provide insight into the neuroprotective gene regulatory mechanisms that enable photoreceptors to withstand light-induced oxidative stress.


Asunto(s)
Drosophila melanogaster/metabolismo , Regulación de la Expresión Génica/fisiología , Luz , Células Fotorreceptoras de Invertebrados/metabolismo , Animales , Canales de Calcio/metabolismo , Drosophila , Expresión Génica/fisiología , Neuroprotección/fisiología , Degeneración Retiniana/metabolismo
9.
J Environ Manage ; 222: 396-401, 2018 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-29870968

RESUMEN

This paper examines the potential detoxification efficiency of heavy metals by phosphate solubilising bacteria (PSB) that were isolated from coral, sea grass and mangrove environment. Initially, four potential bacterial isolates were selected based on their phosphate solubilisation index from 42 strains and were used for the metal tolerance test. Among the four isolates, KSCAS2 exhibited maximum tolerance to heavy metals and the phenotype indicated the production of extra polymeric substances. In a multi-heavy metal experimental setup at two concentrations (100 and 200 mg L-l), it has been demonstrated that the bacteria have extracellularly sequestered metal ions in amorphous deposits and this has been confirmed by scanning electron microscopy. In experiments with a 100 mg L-1 initial metal concentration, the percentages of metal removal by bacteria were 55.23% of Cd, 72.45% of Cr, 76.51% of Cu and 61.51% of Zn, respectively. In subsequent experiments, when the metal concentration was increased up to 200 mg L-l, the metal removal capacity decreased as follows: 44.62%, 63.1%, 67% and 52.80% for Cd, Cr, Cu and Zn, respectively. In addition, the biosorption of heavy metals was confirmed by the Fourier transform infrared Spectroscopy (FT-IR) and scanning electron microscopy (SEM) analysis. The heavy metal concentrations in a broth culture were analysed by inductively coupled plasma-optical emission spectroscopy (ICP-OES). The study suggests that PSB Cronobacter muytjensii KSCAS2 can efficiently remove the heavy metals and these bacteria could be used for the metal removal from the agricultural soils.


Asunto(s)
Antozoos , Cronobacter , Metales Pesados/farmacocinética , Animales , Bacterias , Fosfatos , Espectroscopía Infrarroja por Transformada de Fourier
10.
Gen Comp Endocrinol ; 241: 100-107, 2017 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-27235644

RESUMEN

There is a widespread exposure of general population, including pregnant women and developing fetuses, to the endocrine disrupting chemicals (EDCs). These chemicals have been reported to be present in urine, blood serum, breast milk and amniotic fluid. We aimed to investigate the association between the maternal exposure and in utero fetal exposure levels of these chemicals to study their transfer from maternal to fetal unit indicating prenatal exposure. Samples of maternal blood and amniotic fluid were collected as set from 53 pregnant women at full term. Nine phenolic EDCs, methyl paraben (MP; 20.92ng/mL and 18.92ng/mL), ethyl paraben (EP; 1.97ng/ mL and 1.89ng/mL), propyl paraben (PP; 19.22ng/mL and 18.82ng/mL), butyl paraben (BP; 1.11ng/mL and 1.37ng/mL), p-hydroxybenzoic acid (PHBA; 29.99ng/mL and 26.15ng/mL), bisphenol A (BPA; 7.43ng/mL and 7.75ng/mL), triclosan (TCS; 7.17ng/mL and 7.04ng/mL), octyl phenol (OP; 5.46ng/mL and 5.72ng/mL) and nonyl phenol (NP; 9.38ng/mL and 8.44ng/mL), were simultaneously detected in samples of maternal blood plasma and amniotic fluid respectively using Gas Chromatography-Mass Spectrometry (GC-MS). Highest positive correlation was found for total concentration of 4-nonyl phenol, NP (r=0.575, p<0.001), whereas the lowest positive correlation was found for free form of bisphenol A, BPA (r=0.343, p<0.05), when compared between the two matrices. Our results suggest that maternal exposure to several EDCs is positively associated with in utero exposure to the developing fetus. Future studies should focus on collection of amniotic fluid at different trimesters and the corresponding maternal samples to better characterize the pharmacokinetics and the associated disease etiologies of these EDCs during fetal development.


Asunto(s)
Líquido Amniótico/química , Análisis Químico de la Sangre , Disruptores Endocrinos/análisis , Exposición Materna/estadística & datos numéricos , Fenoles/análisis , Adulto , Compuestos de Bencidrilo/análisis , Compuestos de Bencidrilo/sangre , Disruptores Endocrinos/sangre , Monitoreo del Ambiente/métodos , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos , India/epidemiología , Parabenos/análisis , Fenoles/sangre , Embarazo , Adulto Joven
11.
Eur J Immunol ; 45(10): 2810-20, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26222048

RESUMEN

The impact of the interaction between NK cells and lung dendritic cells (LDCs) on the outcome of respiratory infections is poorly understood. In this study, we investigated the effect and mechanism of NK cells on the function of LDCs during intracellular bacterial lung infection of Chlamydia muridarum in mice. We found that the naive mice receiving LDCs from C. muridarum-infected NK-cell-depleted mice (NK-LDCs) showed more serious body weight loss, bacterial burden, and pathology upon chlamydial challenge when compared with the recipients of LDCs from infected sham-treated mice (NK+LDCs). Cytokine analysis of the local tissues of the former compared with the latter exhibited lower levels of Th1 (IFN-γ) and Th17 (IL-17), but higher levels of Th2 (IL-4), cytokines. Consistently, NK-LDCs were less efficient in directing C. muridarum-specific Th1 and Th17 responses than NK+LDCs when cocultured with CD4(+) T cells. In NK cell/LDC coculture experiments, the blockade of NKG2D receptor reduced the production of IL-12p70, IL-6, and IL-23 by LDCs. The neutralization of IFN-γ in the culture decreased the production of IL-12p70 by LDCs, whereas the blockade of TNF-α resulted in diminished IL-6 production. Our findings demonstrate that NK cells modulate LDC function to elicit Th1/Th17 immunity during intracellular bacterial infection.


Asunto(s)
Infecciones por Chlamydia/inmunología , Chlamydia muridarum/inmunología , Células Dendríticas/inmunología , Células Asesinas Naturales/inmunología , Pulmón/inmunología , Neumonía Bacteriana/inmunología , Células TH1/inmunología , Células Th17/inmunología , Animales , Infecciones por Chlamydia/patología , Citocinas/inmunología , Células Dendríticas/patología , Células Asesinas Naturales/patología , Pulmón/microbiología , Pulmón/patología , Ratones , Subfamilia K de Receptores Similares a Lectina de Células NK/inmunología , Neumonía Bacteriana/microbiología , Neumonía Bacteriana/patología , Células TH1/patología , Células Th17/patología
12.
J Virol ; 89(7): 3497-511, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25568209

RESUMEN

UNLABELLED: In this study, we examined the requirement for host dynein adapter proteins such as dynein light chain 1 (DYNLL1), dynein light chain Tctex-type 1 (DYNLT1), and p150(Glued) in early steps of human immunodeficiency virus type 1 (HIV-1) replication. We found that the knockdown (KD) of DYNLL1, but not DYNLT1 or p150(Glued), resulted in significantly lower levels of HIV-1 reverse transcription in cells. Following an attempt to determine how DYNLL1 could impact HIV-1 reverse transcription, we detected the DYNLL1 interaction with HIV-1 integrase (IN) but not with capsid (CA), matrix (MA), or reverse transcriptase (RT) protein. Furthermore, by mutational analysis of putative DYNLL1 interaction motifs in IN, we identified the motifs (52)GQVD and (250)VIQD in IN as essential for DYNLL1 interaction. The DYNLL1 interaction-defective IN mutant HIV-1 (HIV-1IN(Q53A/Q252A)) exhibited impaired reverse transcription. Through further investigations, we have also detected relatively smaller amounts of particulate CA in DYNLL1-KD cells or in infections with HIV-1IN(Q53A/Q252A) mutant virus. Overall, our study demonstrates the novel interaction between HIV-1 IN and cellular DYNLL1 proteins and suggests the requirement of this virus-cell interaction for proper uncoating and efficient reverse transcription of HIV-1. IMPORTANCE: Host cellular DYNLL1, DYNLT1, and p150(Glued) proteins have been implicated in the replication of several viruses. However, their roles in HIV-1 replication have not been investigated. For the first time, we demonstrated that during viral infection, HIV-1 IN interacts with DYNLL1, and their interaction was found to have a role in proper uncoating and efficient reverse transcription of HIV-1. Thus, interaction of IN and DYNLL1 may be a potential target for future anti-HIV therapy. Moreover, while our study has evaluated the involvement of IN in HIV-1 uncoating and reverse transcription, it also predicts a possible mechanism by which IN contributes to these early viral replication steps.


Asunto(s)
Dineínas Citoplasmáticas/metabolismo , Integrasa de VIH/metabolismo , VIH-1/fisiología , Interacciones Huésped-Patógeno , Transcripción Reversa , Desencapsidación Viral , Secuencias de Aminoácidos , Línea Celular , Análisis Mutacional de ADN , Complejo Dinactina , Dineínas/metabolismo , Técnicas de Silenciamiento del Gen , Integrasa de VIH/genética , VIH-1/genética , Humanos , Proteínas Asociadas a Microtúbulos/metabolismo
13.
Mol Med ; 20: 109-19, 2014 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-24531835

RESUMEN

The role of interleukin-22 (IL-22) in intracellular bacterial infections is a controversial issue, although the contribution of this cytokine to host defense against extracellular bacterial pathogens has been well established. In this study, we focused on an intra-cellular bacterium, Chlamydia, and evaluated the production and function of IL-22 in host defense against chlamydial lung infection using a mouse model. We found that Chlamydia muridarum infection elicited quick IL-22 responses in the lung, which increased during infection and were reduced when bacterial loads decreased. More importantly, blockade of endogenous IL-22 using neutralizing anti-IL-22 monoclonal antibodies (mAb) resulted in more severe disease in the mice, leading to significantly higher weight loss and bacterial growth and much more severe pathological changes than treatment with isotype control antibody. Immunological analyses identified significantly lower T helper 1 (Th1) and Th17 responses in the IL-22-neutralized mice. In contrast, intranasal administration of exogenous IL-22 significantly enhanced protection following chlamydial lung infection, which was associated with a significant increase of Th17 response. The data demonstrate that IL-22 is a critical cytokine, mediating host defense against chlamydial lung infection and coordinating the function of distinct Th-cell subsets, particularly Th1 and Th17, in the process.


Asunto(s)
Infecciones por Chlamydia/inmunología , Chlamydia muridarum , Citocinas/inmunología , Enfermedades Pulmonares/inmunología , Células TH1/inmunología , Células Th17/inmunología , Animales , Infecciones por Chlamydia/genética , Infecciones por Chlamydia/patología , Citocinas/genética , Pulmón/inmunología , Pulmón/patología , Enfermedades Pulmonares/genética , Enfermedades Pulmonares/patología , Ganglios Linfáticos/inmunología , Masculino , Ratones Endogámicos C57BL , ARN Mensajero , Bazo/inmunología
14.
Cells ; 13(2)2024 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-38247825

RESUMEN

Lung macrophage (LM) is vital in host defence against bacterial infections. However, the influence of other innate immune cells on its function, including the polarisation of different subpopulations, remains poorly understood. This study examined the polarisation of LM subpopulations (monocytes/undifferentiated macrophages (Mo/Mφ), interstitial macrophages (IM), and alveolar macrophages (AM)). We further assessed the effect of invariant natural killer T cells (iNKT) on LM polarisation in a protective function against Chlamydia muridarum, an obligate intracellular bacterium, and respiratory tract infection. We found a preferentially increased local Mo/Mφ and IMs with a significant shift to a type-1 macrophage (M1) phenotype and higher expression of iNOS and TNF-α. Interestingly, during the same infection, the alteration of macrophage subpopulations and the shift towards M1 was much less in iNKT KO mice. More importantly, functional testing by adoptively transferring LMs isolated from iNKT KO mice (iNKT KO-Mφ) conferred less protection than those isolated from wild-type mice (WT-Mφ). Further analyses showed significantly reduced gene expression of the JAK/STAT signalling pathway molecules in iNKT KO-Mφ. The data show an important role of iNKT in promoting LM polarisation to the M1 direction, which is functionally relevant to host defence against a human intracellular bacterial infection. The alteration of JAK/STAT signalling molecule gene expression in iNKT KO-Mφ suggests the modulating effect of iNKT is likely through the JAK/STAT pathway.


Asunto(s)
Células T Asesinas Naturales , Humanos , Animales , Ratones , Quinasas Janus , Factores de Transcripción STAT , Transducción de Señal , Macrófagos
15.
Front Microbiol ; 15: 1406190, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39101559

RESUMEN

Challenges from infections caused by biofilms and antimicrobial resistance highlight the need for novel antimicrobials that work in conjunction with antibiotics and minimize resistance risk. In this study we investigated the composite effect of HAMLET (human alpha-lactalbumin made lethal to tumor cells), a human milk protein-lipid complex and amoxicillin on microbial ecology using an ex vivo oral biofilm model with pooled saliva samples. HAMLET was chosen due to its multi-targeted antimicrobial mechanism, together with its synergistic effect with antibiotics on single species pathogens, and low risk of resistance development. The combination of HAMLET and low concentrations of amoxicillin significantly reduced biofilm viability, while each of them alone had little or no impact. Using a whole metagenomics approach, we found that the combination promoted a remarkable shift in overall microbial composition compared to the untreated samples. A large proportion of the bacterial species in the combined treatment were Lactobacillus crispatus, a species with probiotic effects, whereas it was only detected in a minor fraction in untreated samples. Although resistome analysis indicated no major shifts in alpha-diversity, the results showed the presence of TEM beta-lactamase genes in low proportions in all treated samples but absence in untreated samples. Our study illustrates HAMLET's capability to alter the effects of amoxicillin on the oral microbiome and potentially favor the growth of selected probiotic bacteria when in combination. The findings extend previous knowledge on the combined effects of HAMLET and antibiotics against target pathogens to include potential modulatory effects on polymicrobial biofilms of human origin.

16.
J Lab Physicians ; 15(1): 4-19, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37064993

RESUMEN

Soil-transmitted helminths (STH) is a major healthcare challenge in the pediatric age group affecting poor and deprived parts of our community. The main species that infect people are roundworm (AL, Ascaris lumbricoides ), whipworm (TT, Trichuris trichiura ), and hookworms (HW, Ancylostoma duodenale and Necator americanus ). We aimed to estimate the pooled prevalence of STH infections in India in the pediatric age group (< 18 years) and assess the risk factors associated with STH in this age group. Three databases were searched (PubMed, Scopus, and Embase) up to February 16, 2021 with deliberate and inclusive search terms for original research articles estimating the prevalence of either of the three STH in India. Data extracted included individual prevalence of the three STH, prevalence of double or triple infections, and associated risk factors. We identified systematically 1,408 publications, of which 44 were included for the final analysis, including studies from 20 states covering 34,590 children. In our study, the prevalence of AL ranged from 0.8 to 91% with a pooled prevalence of 25%, prevalence of TT ranged from 0.3 to 72% with a pooled prevalence of 13%, and for HW prevalence ranged from 0.2 to 80% with pooled prevalence of 10%. Two most important risk factors with higher odds ratio were open defecation practices or open latrine (odds ratio: 5.2) and washing hands without soap using water only (odds ratio: 2.49). Knowledge of areas with high prevalence of STH and associated risk factors would help in designing effective control strategies in the high-risk groups to prevent infection and aid in a drastic reduction of morbidity in children.

17.
Antibiotics (Basel) ; 12(2)2023 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-36830333

RESUMEN

Emerging evidence suggests differential effects of therapeutic antibiotics on infant T cell responses to pathogens. In this study, we explored the impact of the treatment of mouse infants with amoxicillin and the human milk-derived antimicrobial HAMLET (human alpha-lactalbumin made lethal to tumor cells) on T cell responses to Streptococcus pneumoniae. Lung cells and splenocytes were isolated from the infant mice subjected to intranasal administration of amoxicillin, HAMLET, or a combination of HAMLET and amoxicillin, and cultured with S. pneumoniae to measure T cell responses. After in-vitro stimulation with S. pneumoniae, lung cells from amoxicillin- or amoxicillin plus HAMLET-treated mice produced lower levels of Th17 (IL-17A), but not Th1 (IFN-γ), cytokine than mice receiving HAMLET or PBS. IL-17A/IFN-γ cytokine levels produced by the stimulated splenocytes, on the other hand, revealed no significant difference among treatment groups. Further analysis of T cell cytokine profiles by flow cytometry showed that lung CD4+, but not CD8+, T cells from amoxicillin- or HAMLET plus amoxicillin-treated mice expressed decreased levels of IL-17A compared to those from HAMLET-exposed or control mice. Collectively, these results indicate that exposure of infant mice to amoxicillin, but not HAMLET, may suppress lung Th17 responses to S. pneumoniae.

18.
Cureus ; 15(6): e40023, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37425605

RESUMEN

OBJECTIVE: We aim to find the time in which a thawed citrate plasma sample that was preserved can be analyzed for routine coagulation testing without losing precision. METHODS: Whole blood samples from 30 healthy volunteers were collected in 3.2% sodium citrate vacutainer and centrifuged to separate platelet-poor plasma. Each sample was then aliquoted, one aliquot was used immediately for prothrombin time (PT)-international normalized ratio (INR) and activated partial thromboplastin time (APTT), four were stored at -20°C, and four were stored at -80°C for 24 hours. After 24 hours, the aliquots were taken out and thawed at 37°C in water bath and analyzed after 15, 30, 60, and 120 minutes. STATISTICAL ANALYSIS: Data were presented as mean with standard deviation (SD). Repeated measures ANOVA with Tukey post-hoc test was performed for multiple comparisons. All analysis was done using GraphPAD Prism 8.0 software (GraphPad Software, San Diego, California, USA).  Results: In the case of PT and INR, no statistically significant difference was found between the mean values after thawing for 120 minutes when compared with the mean baseline value. However, the APTT showed a statistically significant difference (p = 0.0232) after 30 minutes of thawing when the sample was stored at -20°C. Furthermore, a statistically significance difference (p = 0.0001) was found after 60 minutes of thawing when the samples were stored at -80°C. CONCLUSION: Plasma samples for the PT and INR may be accepted for assessment up to 120 minutes, when stored at -20°C and -80°C for 24 hours. In the case of APTT, the plasma sample can be used for assessment up to 30 minutes after thawing when stored at -20°C and up to 60 minutes when stored at -80°C.

19.
Front Microbiol ; 14: 1233605, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37731928

RESUMEN

It is widely acknowledged that conventional mining and extraction techniques have left many parts of the world with depleting coal reserves. A sustainable method for improving the recovery of natural gas from coalbeds involves enhancing the production of biogenic methane in coal mines. By taking a culture-independent approach, the diversity of the microbial community present in the formation water of an Indian reservoir was examined using 16S rRNA gene amplification in order to study the potential of microbial-enhanced coal bed methane (CBM) production from the deep thermogenic wells at a depth of 800-1200 m. Physicochemical characterization of formation water and coal samples was performed with the aim of understanding the in situ reservoir conditions that are most favorable for microbial CBM production. Microbial community analysis of formation water showed that bacteria were more abundant than archaea. Proteobacteria, Firmicutes, and Bacteroidetes were found as the most prevalent phyla in all the samples. These phyla play a crucial role in providing substrate for the process of methanogenesis by performing fermentative, hydrolytic, and syntrophic functions. Considerable variation in the abundance of microbial genera was observed amongst the selected CBM wells, potentially due to variable local geochemical conditions within the reservoir. The results of our study provide insights into the impact of geochemical factors on microbial distribution within the reservoir. Further, the study demonstrates lab-scale enhancement in methane production through nutrient amendment. It also focuses on understanding the microbial diversity of the Raniganj coalbed methane block using amplicon sequencing and further recognizing the potential of biogenic methane enhancement through microbial stimulation. The findings of the study will help as a reference for better strategization and implementation of on-site microbial stimulation for enhanced biogenic methane production in the future.

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