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1.
J Clin Microbiol ; 59(7): e0038821, 2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-33827901

RESUMO

The coronavirus disease 19 (COVID-19) pandemic continues to impose a significant burden on global health infrastructure. While identification and containment of new cases remain important, laboratories must now pivot and consider an assessment of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immunity in the setting of the recent availability of multiple COVID-19 vaccines. Here, we have utilized the latest Abbott Alinity semiquantitative IgM and quantitative IgG spike protein (SP) serology assays (IgMSP and IgGSP) in combination with Abbott Alinity IgG nucleocapsid (NC) antibody test (IgGNC) to assess antibody responses in a cohort of 1,236 unique participants comprised of naive, SARS-CoV-2-infected, and vaccinated (including both naive and recovered) individuals. The IgMSP and IgGSP assays were highly specific (100%) with no cross-reactivity to archived samples collected prior to the emergence of SARS-CoV-2, including those from individuals with seasonal coronavirus infections. Clinical sensitivity was 96% after 15 days for both IgMSP and IgGSP assays individually. When considered together, the sensitivity was 100%. A combination of NC- and SP-specific serologic assays clearly differentiated naive, SARS-CoV-2-infected, and vaccine-related immune responses. Vaccination resulted in a significant increase in IgGSP and IgMSP values, with a major rise in IgGSP following the booster (second) dose in the naive group. In contrast, SARS-CoV-2-recovered individuals had several-fold higher IgGSP responses than naive following the primary dose, with a comparatively dampened response following the booster. This work illustrates the strong clinical performance of these new serological assays and their utility in evaluating and distinguishing serological responses to infection and vaccination.


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Antivirais , Vacinas contra COVID-19 , Humanos , Imunoglobulina G , Imunoglobulina M , Sensibilidade e Especificidade , Glicoproteína da Espícula de Coronavírus
2.
Int J Mol Sci ; 20(5)2019 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-30857270

RESUMO

Worldwide, women account for approximately 51% of human immunodeficiency virus-1 (HIV) seropositive individuals. The prevalence of neuropathic pain among individuals with HIV and a lack of preclinical data characterizing sex differences prompted us to address this knowledge gap. C57BL/6 male and female mice received multiple intrathecal injections of HIV-glycoprotein 120 (gp120), followed by determination of mechanical allodynia and thermal hypersensitivity for four weeks. The influence of ovarian hormones in the gp120 pain model was evaluated by comparison of ovariectomized (OVX) mice versus sham control. We found that gp120-induced neuropathic pain-like behaviors are sex-dependent. Female mice showed both increased mechanical allodynia and increased cold sensitivity relative to their male counterparts. The OVX mice showed reduced pain sensitivity compared to sham, suggesting a role of the ovarian hormones in sex differences in pain sensitivity to gp120. Gp120-induced neuropathic pain caused a shift in estrous cycle toward the estrus phase. However, there is a lack of clear correlation between the estrous cycle and the development of neuropathic pain-like behaviors during the four week recording period. This data provided the first evidence for sex differences in a rodent model of HIV-related neuropathic pain, along with a potential role of ovarian hormones.


Assuntos
Proteína gp120 do Envelope de HIV/metabolismo , Infecções por HIV/complicações , HIV-1/isolamento & purificação , Hiperalgesia/etiologia , Neuralgia/etiologia , Animais , Modelos Animais de Doenças , Feminino , Infecções por HIV/virologia , Humanos , Hiperalgesia/metabolismo , Hiperalgesia/virologia , Masculino , Camundongos Endogâmicos C57BL , Neuralgia/metabolismo , Neuralgia/virologia , Fatores Sexuais
3.
J Neurosci ; 37(6): 1378-1393, 2017 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-28011743

RESUMO

Neuroplasticity in the amygdala drives pain-related behaviors. The central nucleus (CeA) serves major amygdala output functions and can generate emotional-affective behaviors and modulate nocifensive responses. The CeA receives excitatory and inhibitory inputs from the basolateral nucleus (BLA) and serotonin receptor subtype 5-HT2CR in the BLA, but not CeA, has been implicated anxiogenic behaviors and anxiety disorders. Here, we tested the hypothesis that 5-HT2CR in the BLA plays a critical role in CeA plasticity and neuropathic pain behaviors in the rat spinal nerve ligation (SNL) model. Local 5-HT2CR knockdown in the BLA with stereotaxic injection of 5-HT2CR shRNA AAV vector decreased vocalizations and anxiety- and depression-like behaviors and increased sensory thresholds of SNL rats, but had no effect in sham controls. Extracellular single-unit recordings of CeA neurons in anesthetized rats showed that 5-HT2CR knockdown blocked the increase in neuronal activity (increased responsiveness, irregular spike firing, and increased burst activity) in SNL rats. At the synaptic level, 5-HT2CR knockdown blocked the increase in excitatory transmission from BLA to CeA recorded in brain slices from SNL rats using whole-cell patch-clamp conditions. Inhibitory transmission was decreased by 5-HT2CR knockdown in control and SNL conditions to a similar degree. The findings can be explained by immunohistochemical data showing increased expression of 5-HT2CR in non-GABAergic BLA cells in SNL rats. The results suggest that increased 5-HT2CR in the BLA contributes to neuropathic-pain-related amygdala plasticity by driving synaptic excitation of CeA neurons. As a rescue strategy, 5-HT2CR knockdown in the BLA inhibits neuropathic-pain-related behaviors.SIGNIFICANCE STATEMENT Neuroplasticity in the amygdala has emerged as an important pain mechanism. This study identifies a novel target and rescue strategy to control abnormally enhanced amygdala activity in an animal model of neuropathic pain. Specifically, an integrative approach of gene transfer, systems and brain slice electrophysiology, behavior, and immunohistochemistry was used to advance the novel concept that serotonin receptor subtype 5-HT2C contributes critically to the imbalance between excitatory and inhibitory drive of amygdala output neurons. Local viral vector-mediated 5-HT2CR knockdown in the amygdala normalizes the imbalance, decreases neuronal activity, and inhibits neuropathic-pain-related behaviors. The study provides valuable insight into serotonin receptor (dys)function in a limbic brain area.


Assuntos
Tonsila do Cerebelo/metabolismo , Técnicas de Silenciamento de Genes , Neuralgia/metabolismo , Plasticidade Neuronal/fisiologia , Medição da Dor/métodos , Receptor 5-HT2C de Serotonina/deficiência , Animais , Técnicas de Silenciamento de Genes/métodos , Masculino , Aprendizagem em Labirinto/fisiologia , Neuralgia/genética , Técnicas de Cultura de Órgãos , Ratos , Ratos Sprague-Dawley , Receptor 5-HT2C de Serotonina/genética , Vocalização Animal/fisiologia
4.
Int J Mol Sci ; 19(5)2018 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-29786653

RESUMO

Earlier, we reported that gestational ethanol (E) can dysregulate neuron glutathione (GSH) homeostasis partially via impairing the EAAC1-mediated inward transport of Cysteine (Cys) and this can affect fetal brain development. In this study, we investigated if there is a role for the transulfuration pathway (TSP), a critical bio-synthetic point to supply Cys in E-induced dysregulation of GSH homeostasis. These studies utilized an in utero E binge model where the pregnant Sprague⁻Dawley (SD) rat dams received five doses of E at 3.5 g/kg by gastric intubation beginning embryonic day (ED) 17 until ED19 separated by 12 h. The postnatal day 7 (PN7) alcohol model employed an oral dosing of 4 g/kg body weight split into 2 feedings at 2 h interval and an iso-caloric and iso-volumic equivalent maltose-dextrin milk solution served as controls. The in vitro model consisted of cerebral cortical neuron cultures from embryonic day (ED) 16⁻17 fetus from SD rats and differentiated neurons from ED18 rat cerebral cortical neuroblasts. E concentrations were 4 mg/mL. E induced an accumulation of cystathionine in primary cortical neurons (PCNs), 2nd trimester equivalent in utero binge, and 3rd trimester equivalent PN7 model suggesting that breakdown of cystathionine, a required process for Cys supply is impaired. This was associated with a significant reduction in cystathionine γ-lyase (CSE) protein expression in PCN (p < 0.05) and in fetal cerebral cortex in utero (53%, p < 0.05) without a change in the expression of cystathionine ß-synthase (CBS). Concomitantly, E decreased Cse mRNA expression in PCNs (by 32% within 6 h of exposure, p < 0.05) and in fetal brain (33%, p < 0.05). In parallel, knock down of CSE in differentiated rat cortical neuroblasts exaggerated the E-induced ROS, GSH loss with a pronounced caspase-3 activation and cell death. These studies illustrate the importance of TSP in CSE-related maintenance of GSH and the downstream events via Cys synthesis in neurons and fetal brain.


Assuntos
Depressores do Sistema Nervoso Central/toxicidade , Córtex Cerebral/efeitos dos fármacos , Cistationina gama-Liase/metabolismo , Etanol/toxicidade , Glutationa/metabolismo , Homeostase , Lesões Pré-Natais/metabolismo , Animais , Células Cultivadas , Córtex Cerebral/embriologia , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Cisteína/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Lesões Pré-Natais/etiologia , Ratos , Ratos Sprague-Dawley
6.
FASEB J ; 30(5): 1865-79, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26839378

RESUMO

Recently we have reported that age-dependent decline in antioxidant levels accelerated apoptosis and skeletal muscle degeneration. Here, we demonstrate genetic ablation of the master cytoprotective transcription factor, nuclear factor (erythroid-derived-2)-like 2 (Nrf2), aggravates cardiotoxin (CTX)-induced tibialis anterior (TA) muscle damage. Disruption of Nrf2 signaling sustained the CTX-induced burden of reactive oxygen species together with compromised expression of antioxidant genes and proteins. Transcript/protein expression of phenotypic markers of muscle differentiation, namely paired box 7 (satellite cell) and early myogenic differentiation and terminal differentiation (myogenin and myosin heavy chain 2) were increased on d 2 and 4 postinjury but later returned to baseline levels on d 8 and 15 in wild-type (WT) mice. In contrast, these responses were persistently augmented in Nrf2-null mice suggesting that regulation of the regeneration-related signaling mechanisms require Nrf2 for normal functioning. Furthermore, Nrf2-null mice displayed slower regeneration marked by dysregulation of embryonic myosin heavy chain temporal expression. Histologic observations illustrated that Nrf2-null mice displayed smaller, immature TA muscle fibers compared with WT counterparts on d 15 after CTX injury. Improvement in TA muscle morphology and gain in muscle mass evident in the WT mice was not noticeable in the Nrf2-null animals. Taken together these data show that the satellite cell activation, proliferation, and differentiation requires a functional Nrf2 system for effective healing following injury.-Shelar, S. B., Narasimhan, M., Shanmugam, G., Litovsky, S. H., Gounder, S. S., Karan, G., Arulvasu, C., Kensler, T. W., Hoidal, J. R., Darley-Usmar, V. M., Rajasekaran, N. S. Disruption of nuclear factor (erythroid-derived-2)-like 2 antioxidant signaling: a mechanism for impaired activation of stem cells and delayed regeneration of skeletal muscle.


Assuntos
Antioxidantes/fisiologia , Cardiotoxinas/toxicidade , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/crescimento & desenvolvimento , Fator 2 Relacionado a NF-E2/metabolismo , Transdução de Sinais/fisiologia , Envelhecimento , Animais , Linhagem Celular , Proliferação de Células/fisiologia , Regulação da Expressão Gênica/fisiologia , Humanos , Camundongos , Camundongos Knockout , Fator 2 Relacionado a NF-E2/genética , Regeneração/fisiologia , Células Satélites de Músculo Esquelético/fisiologia , Células-Tronco
7.
Adv Exp Med Biol ; 999: 231-255, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29022266

RESUMO

Cardiovascular dysfunction and heart failure associated with aging not only impairs the cardiac function but also the quality of life eventually decreasing the life expectancy of the elderly. Notably, cardiac tissue can prematurely age under certain conditions such as genetic mutation, persistent redox stress and overload, aberrant molecular signaling, DNA damage, telomere attrition, and other pathological insults. While cardiovascular-related morbidity and mortality is on the rise and remains a global health threat, there has been only little to moderate improvements in its medical management. This is due to the fact that the lifestyle changes to molecular mechanisms underlying age-related myocardial structure and functional remodeling are multifactorial and intricately operate at different levels. Along these lines, the intrinsic redox mechanisms and oxidative stress (OS) are widely studied in the myocardium. The accumulation of reactive oxygen species (ROS) with age and the resultant oxidative damage has been shown to increase the susceptibility of the myocardium to multiple complications such as atherosclerosis, hypertension, ischemic heart disease, cardiac myopathy, and heart failure. There has been growing interest in trying to enhance the mechanisms that neutralize the ROS and curtailing OS as a possible anti-aging intervention and as a treatment for age-related disorders. Natural defense system to fight against OS involves a master transcription factor named nuclear erythroid-2-p45-related factor-2 (Nrf2) that regulates several antioxidant genes. Compelling evidence exists on the Nrf2 gain of function through pharmacological interventions in counteracting the oxidative damage and affords cytoprotection in several organs including but not limited to lung, liver, kidney, brain, etc. Nevertheless, thus far, only a few studies have described the potential role of Nrf2 and its non-pharmacological induction in cardiac aging. This chapter explores the effects of various modes of exercise on Nrf2 signaling along with its responses and ramifications on the cascade of OS in the aging heart.


Assuntos
Envelhecimento , Antioxidantes/metabolismo , Exercício Físico , Miocárdio/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Animais , Humanos , Oxirredução , Estresse Oxidativo , Qualidade de Vida , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
8.
Int J Mol Sci ; 18(12)2017 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-29206135

RESUMO

Central among the fetotoxic responses to in utero ethanol (E) exposure is redox-shift related glutathione (GSH) loss and apoptosis. Previously, we reported that despite an E-generated Nrf2 upregulation, fetal neurons still succumb. In this study, we investigate if the compromised GSH results from an impaired inward transport of cysteine (Cys), a precursor of GSH in association with dysregulated excitatory amino acid carrier1 (EAAC1), a cysteine transporter. In utero binge model involves administration of isocaloric dextrose or 20% E (3.5 g/kg)/ by gavage at 12 h intervals to pregnant Sprague Dawley (SD) rats, starting gestation day (gd) 17 with a final dose on gd19, 2 h prior to sacrifice. Primary cerebral cortical neurons (PCNs) from embryonic day 16-17 fetal SD rats were the in vitro model. E reduced both PCN and cerebral cortical GSH and Cys up to 50% and the abridged GSH could be blocked by administration of N-acetylcysteine. E reduced EAAC1 protein expression in utero and in PCNs (p < 0.05). This was accompanied by a 60-70% decrease in neuron surface expression of EAAC1 along with significant reductions of EAAC1/Slc1a1 mRNA (p < 0.05). In PCNs, EAAC1 knockdown significantly decreased GSH but not oxidized glutathione (GSSG) illustrating that while not the sole provider of Cys, EAAC1 plays an important role in neuron GSH homeostasis. These studies strongly support the concept that in both E exposed intact fetal brain and cultured PCNs a mechanism underlying E impairment of GSH homeostasis is reduction of import of external Cys which is mediated by perturbations of EAAC1 expression/function.


Assuntos
Transporte Biológico/efeitos dos fármacos , Cisteína/metabolismo , Etanol/farmacologia , Transportador 3 de Aminoácido Excitatório/metabolismo , Animais , Células Cultivadas , Córtex Cerebral/citologia , Glutationa/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
9.
Biochim Biophys Acta ; 1852(1): 53-60, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25446995

RESUMO

Redox homeostasis is essential for basal signaling of several physiological processes, but a unilateral shift towards an 'oxidative' or 'reductive' trait will alter intracellular redox milieu. Typically, such an event influences the structure and the native function of a cell or an organelle. Numerous experimental research and clinical trials over the last 6 decades have demonstrated that enhanced oxygen-derived free radicals constitute a major stimulus to trigger damage in several human diseases, including cardiovascular complications supporting the theory of oxidative stress (OS). However, until our key discovery, the dynamic interrelationship between "Reductive Stress (RS)" and cardiac health has been obscured by overwhelming OS studies (Rajasekaran et al., 2007). Notably, this seminal finding spurred considerable interest in investigations of other mechanistic insights, and thus far the results indicate a similar or stronger role for RS, as that of OS. In addition, from our own findings we strongly believe that constitutive activation of pathways that enable sustained generation of reducing equivalents of glutathione (GSH), reduced nicotinamide adenine dinucleotide phosphate (NADPH) will cause RS and impair the basal cellular signaling mechanisms operating through harmless pro-oxidative events, in turn, disrupting single and/or a combination of key cellular processes such as growth, maturation, differentiation, survival, death etc., that govern healthy cell physiology. Here, we have discussed the role of RS as a causal or contributing factor in relevant pathophysiology of a major cardiac disease of human origin.


Assuntos
Cardiomiopatias/metabolismo , Proteínas Musculares/metabolismo , Animais , Homeostase , Humanos , Camundongos , Oxirredução , Estresse Oxidativo
10.
J Transl Med ; 14: 86, 2016 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-27048381

RESUMO

BACKGROUND: Anomalies in myocardial structure involving myocyte growth, hypertrophy, differentiation, apoptosis, necrosis etc. affects its function and render cardiac tissue more vulnerable to the development of heart failure. Although oxidative stress has a well-established role in cardiac remodeling and dysfunction, the mechanisms linking redox state to atrial cardiomyocyte hypertrophic changes are poorly understood. Here, we investigated the role of nuclear erythroid-2 like factor-2 (Nrf2), a central transcriptional mediator, in redox signaling under high intensity exercise stress (HIES) in atria. METHODS: Age and sex-matched wild-type (WT) and Nrf2(-/-) mice at >20 months of age were subjected to HIES for 6 weeks. Gene markers of hypertrophy and antioxidant enzymes were determined in the atria of WT and Nrf2(-/-) mice by real-time qPCR analyses. Detection and quantification of antioxidants, 4-hydroxy-nonenal (4-HNE), poly-ubiquitination and autophagy proteins in WT and Nrf2(-/-) mice were performed by immunofluorescence analysis. The level of oxidative stress was measured by microscopical examination of di-hydro-ethidium (DHE) fluorescence. RESULTS: Under the sedentary state, Nrf2 abrogation resulted in a moderate down regulation of some of the atrial antioxidant gene expression (Gsr, Gclc, Gstα and Gstµ) despite having a normal redox state. In response to HIES, enlarged atrial myocytes along with significantly increased gene expression of cardiomyocyte hypertrophy markers (Anf, Bnf and ß-Mhc) were observed in Nrf2(-/-) when compared to WT mice. Further, the transcript levels of Gclc, Gsr and Gstµ and protein levels of NQO1, catalase, GPX1 were profoundly downregulated along with GSH depletion and increased oxidative stress in Nrf2(-/-) mice when compared to its WT counterparts after HIES. Impaired antioxidant state and profound oxidative stress were associated with enhanced atrial expression of LC3 and ATG7 along with increased ubiquitination of ATG7 in Nrf2(-/-) mice subjected to HIES. CONCLUSIONS: Loss of Nrf2 describes an altered biochemical phenotype associated with dysregulation in genes related to redox state, ubiquitination and autophagy in HIES that result in atrial hypertrophy. Therefore, our findings direct that preserving Nrf2-related antioxidant function would be one of the effective strategies to safeguard atrial health.


Assuntos
Antioxidantes/metabolismo , Deleção de Genes , Átrios do Coração/metabolismo , Átrios do Coração/patologia , Fator 2 Relacionado a NF-E2/metabolismo , Condicionamento Físico Animal , Transdução de Sinais , Estresse Fisiológico , Envelhecimento/patologia , Animais , Autofagia , Regulação para Baixo/genética , Imunofluorescência , Glutationa/metabolismo , Hipertrofia , Peroxidação de Lipídeos , Camundongos Endogâmicos C57BL , Modelos Biológicos , Fator 2 Relacionado a NF-E2/deficiência , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Transcrição Gênica , Proteínas Ubiquitinadas/metabolismo
11.
J Biomed Sci ; 23: 6, 2016 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-26786850

RESUMO

BACKGROUND: Developing brain is a major target for alcohol's actions and neurological/functional abnormalities include microencephaly, reduced frontal cortex, mental retardation and attention-deficits. Previous studies have shown that ethanol altered the lateral ventricular neuroepithelial cell proliferation. However, the effect of ethanol on subventricular basal progenitors which generate majority of the cortical layers is not known. METHODS: We utilized spontaneously immortalized rat brain neuroblasts obtained from cultures of 18-day-old fetal rat cerebral cortices using in vitro ethanol exposures and an in utero binge model. In the in vitro acute model, cells were exposed to 86 mM ethanol for 8, 12 and 24 h. The second in vitro model comprised of chronic intermittent ethanol (CIE) exposure which consisted of 14 h of ethanol treatment followed by 10 h of withdrawal with three repetitions. RESULTS: E18 neuroblasts expressing Tbr2 representing immature basal progenitors displayed significant reduction of proliferation in response to ethanol in both the models. The decreased proliferation was accompanied by absence of apoptosis or autophagy as illustrated by FACS analysis and expression of apoptotic and autophagic markers. The BrdU incorporation assay indicated that ethanol enhanced the accumulation of cells at G1 with reduced cell number in S phase. In addition, the ethanol-inhibited basal neuroblasts proliferation was connected to decrease in cyclin D1 and Rb phosphorylation indicating cell cycle arrest. Further, in utero ethanol exposure in pregnant rats during E15-E18 significantly decreased Tbr2 and cyclin D1 positive cell number in cerebral cortex of embryos as assessed by cell sorting analysis by flow cytometry. CONCLUSIONS: Altogether, the current findings demonstrate that ethanol impacts the expansion of basal progenitors by inducing cytostasis that might explain the anomalies of cortico-cerebral development associated with fetal alcohol syndrome.


Assuntos
Transtornos do Sistema Nervoso Induzidos por Álcool/metabolismo , Etanol/toxicidade , Transtornos do Espectro Alcoólico Fetal/metabolismo , Lobo Frontal/metabolismo , Fase G1/efeitos dos fármacos , Células-Tronco Neurais/metabolismo , Fase S/efeitos dos fármacos , Transtornos do Sistema Nervoso Induzidos por Álcool/patologia , Animais , Ciclina D1/metabolismo , Feminino , Transtornos do Espectro Alcoólico Fetal/patologia , Lobo Frontal/patologia , Células-Tronco Neurais/patologia , Gravidez , Ratos , Proteínas com Domínio T/metabolismo
12.
Diagnostics (Basel) ; 14(16)2024 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-39202232

RESUMO

Inflammatory bowel disease (IBD) is characterized by chronic inflammation of the gastrointestinal (GI) tract. Fecal calprotectin (fCAL) is a noninvasive laboratory test used in the diagnosis and monitoring of IBDs such as Crohn's disease and ulcerative colitis. The fCAL send-out test that our facility has been offering so far uses an ELISA-based method. In the current study, we sought to validate the performance of a Buhlmann fCAL turbo assay in an automated Abbott Alinity C analyzer (AFCAL) in our core laboratory. Five-day imprecision studies showed good performance for both within-run (5.3%) and between-day (2.5%) measurements. The reportable range was verified as 30-20,000 µg/g. Deming regression and Bland-Altman analysis indicated a strong correlation of r = 0.99 with a low, acceptable bias of 1.8% for AFCAL relative to the predicate Buhlmann fCAL ELISA results. AFCAL's clinical performance was determined retrospectively in 62 patients with ICD codes for IBD. Overall, the implementation of AFCAL in our routine clinical testing has improved our turnaround time, reduced the cost per test, and significantly increased our clinician satisfaction.

13.
J Appl Lab Med ; 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39045839

RESUMO

BACKGROUND: Recently, a major manufacturer recalled several lots of iron assay reagent due to positive bias of roughly 15%-30% and the cause remains unknown. This study investigated the root cause of this positive bias and evaluated a simple practical approach to improve the assay. METHODS: Performance comparison of recalled and unimpacted iron assay kits was done utilizing calibrators, quality control (QC) materials, and 42 remnant patient samples. Spectral scan and trace elements analysis of R1 and R2 reagents was performed. Copper (Cu) and thiourea (TU) spiking experiments were utilized to elucidate the cause and prevention of positive bias seen with recalled lots. RESULTS: Iron measurements in QC materials and patient samples using recalled reagents generated a positive bias of 17.5% and 21%, respectively. Correspondingly, the recalled R2 reagents, but not R1, showed a rise in basal absorbance along with an unanticipated presence of Cu (22.7 µg/dL) and lead (7.5 µg/L). Cu spiking to recalled and unimpacted R2 reagent intensified the reagent color besides falsely increasing its absorbance, calibration factor, and patient iron measurements. Interestingly, addition of TU (65 mmol/L) to R2 reagent from unimpacted lot prevented the short-term and prolonged Cu-induced spurious rise in calibration factor and patient iron estimations. CONCLUSIONS: We conclude that accidental copper contamination of R2 reagent during manufacturing could be a reason underlying the positive bias in the recalled iron reagent lots. Addition of TU in ferene-containing R2 reagent is a simple and effective means to prevent Cu-induced false elevation in iron values.

14.
Alcohol Clin Exp Res ; 37(1): 96-109, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22757755

RESUMO

BACKGROUND: Prenatal exposure to ethanol (EtOH) elicits a range of neuro-developmental abnormalities, microcephaly to behavioral deficits. Impaired protein synthesis has been connected to pathogenesis of EtOH-induced brain damage and abnormal neuron development. However, mechanisms underlying these impairments of protein synthesis are not known. In this study, we illustrate the effects of EtOH on programmed cell death protein 4 (PDCD4), a tumor and translation repressor. METHODS: Primary cortical neurons (PCNs) were treated with 2.5 and 4 mg/ml EtOH for different time points (4 to 24 hours), and PDCD4 expression was detected by Western blotting. Protein synthesis was determined using [(35) S] methionine incorporation assay. Methyl cap pull-down assay was performed to establish the effect of EtOH on association of eukaryotic initiation factor 4A (eIF4A) with capped mRNA. Luciferase assay was performed to determine the in vivo translation. A 2-day acute 5-dose binge model with EtOH (4 g/kg body wt, 25% v/v) was performed in Sprague-Dawley rats at 12-hour intervals and analyzed for PDCD4, eIF4A, and eIF4A-methyl cap association. RESULTS: EtOH increased PDCD4 expression in a time- and dose-dependent manner in PCNs, which inhibited the association of eIF4A with methyl cap. EtOH and ectopic PDCD4 expression suppressed in vivo translation in PCNs and RNAi targeting of PDCD4 blocked the inhibitory effect of EtOH on protein synthesis. In utero exposure of pregnant rats to EtOH resulted in a significant increase in PDCD4 in fetal cerebral cortex along with the inhibition of methyl cap-associated eIF4A, compared with isocaloric controls. Increased PDCD4 also occurred in pooled fractions of remaining brain regions. CONCLUSIONS: Our data, for the first time, illustrate that PDCD4 mediates inhibitory effects of EtOH on protein synthesis in PCNs and developing brain.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Córtex Cerebral/efeitos dos fármacos , Etanol/farmacologia , Neurônios/efeitos dos fármacos , Biossíntese de Proteínas/efeitos dos fármacos , Animais , Consumo Excessivo de Bebidas Alcoólicas/metabolismo , Núcleo Celular/metabolismo , Depressores do Sistema Nervoso Central/farmacologia , Córtex Cerebral/citologia , Córtex Cerebral/embriologia , Córtex Cerebral/metabolismo , Citoplasma/metabolismo , Fator de Iniciação 4A em Eucariotos/metabolismo , Feminino , Transtornos do Espectro Alcoólico Fetal/etiologia , Neurônios/metabolismo , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley
15.
Alcohol Clin Exp Res (Hoboken) ; 47(8): 1530-1543, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37364904

RESUMO

BACKGROUND: Prenatal ethanol exposure hinders oxidative stress-mediated neuroblast/neural progenitor cell proliferation by inhibiting G1-S transition, a process vital to neocortical development. We previously showed that ethanol elicits this redox imbalance by repressing cystathionine γ-lyase (CSE), the rate-limiting enzyme in the transsulfuration pathway in fetal brain and cultured cerebral cortical neurons. However, the mechanism by which ethanol impacts the CSE pathway in proliferating neuroblasts is not known. We conducted experiments to define the effects of ethanol on CSE regulation and the molecular signaling events that control this vital pathway. This enabled us to develop an intervention to prevent the ethanol-associated cytostasis. METHODS: Spontaneously immortalized undifferentiated E18 rat neuroblasts from brain cerebral cortex were exposed to ethanol to mimic an acute consumption pattern in humans. We performed loss- and gain-of-function studies to evaluate whether NFATc4 is a transcriptional regulator of CSE. The neuroprotective effects of chlorogenic acid (CGA) against the effects of ethanol were assessed using ROS and GSH/GSSG assays as measures of oxidative stress, transcriptional activation of NFATc4, and expression of NFATc4 and CSE by qRT-PCR and immunoblotting. RESULTS: Ethanol treatment of E18-neuroblast cells elicited oxidative stress and significantly reduced CSE expression with a concomitant decrease in NFATc4 transcriptional activation and expression. In parallel, inhibition of the calcineurin/NFAT pathway by FK506 exaggerated ethanol-induced CSE loss. In contrast, NFATc4 overexpression prevented loss of ethanol-induced CSE. CGA increased and activated NFATc4, amplified CSE expression, rescued ethanol-induced oxidative stress, and averted the cytostasis of neuroblasts by rescuing cyclin D1 expression. CONCLUSIONS: These findings demonstrate that ethanol can perturb CSE-dependent redox homeostasis by impairing the NFATc4 signaling pathway in neuroblasts. Notably, ethanol-associated impairments were rescued by genetic or pharmacological activation of NFATc4. Furthermore, we found a potential role for CGA in mitigating the ethanol-related neuroblast toxicity with a compelling connection to the NFATc4/CSE pathway.

16.
Viruses ; 15(10)2023 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-37896822

RESUMO

The presence of a certain group of auto-antibodies (AAbs) is known to correlate with the severity of COVID-19. It is, however, unknown if such AAbs are prevalent and impact COVID-19-related outcomes in lung transplant recipients (LTRs) who are immunosuppressed. We performed a retrospective study of LTRs with COVID-19 and analyzed samples before and after COVID-19 for IgG AAbs. AAbs analysis was carried out using autoimmune and coronavirus microarray and the resulting cross-sectional differences in Ab-scores and clinical variables were analyzed using Fischer's Exact test for categorical variables and a paired t-test for continuous variables. Linear regression was used to analyze the differences in Ab-scores and COVID-19 severity. LTRs with non-severe [NS gp (n = 10)], and severe [S gp (n = 8)] COVID-19 disease were included. Ferritin and acute respiratory failure were higher in the S group (p = 0.03; p < 0.0001). Among the AAbs analyzed, interferon-related AAbs (IFN-alpha2, IFN-beta, IFN lamba, IFN-epsilon), eight interleukin-related AAbs, and several tissue-related AAbs were also found to be changed significantly from pre- to post-COVID-19 (p < 0.05). IFN-lambda (p = 0.03) and IL-22 (p = 0.002) were significantly associated with COVID-19 severity and remained significant in linear regression analysis while controlling for other variables. AAbs are common in LTRs, and certain groups of antibodies are particularly enhanced in LTRs with severe COVID-19. Preliminary observations of this study need to be confirmed by a larger sample size.


Assuntos
COVID-19 , Humanos , Autoimunidade , Estudos Retrospectivos , Transplantados , Estudos Transversais , Imunoglobulina G , Pulmão
17.
J Cell Mol Med ; 16(8): 1750-7, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22004076

RESUMO

On the basis of increasing roles for HDM2 oncoprotein in cancer growth and progression, we speculated that HDM2 might play a major role in hypoxia-induced metastatic process. For verification of this hypothesis, wild-type LNCaP prostate cancer cells and HDM2 transfected LNCaP-MST (HDM2 stably transfected) cells were studied. The data obtained from our experiments revealed that the HDM2 transfected LNCaP-MST cells possessed an ability to multiply rapidly and show distinct morphological features compared to non-transfected LNCaP cells. During exposures to hypoxia HDM2 expression in the LNCaP and LNCaP-MST cells was significantly higher compared to the normoxic levels. The LNCaP-MST cells also expressed higher levels of HIF-1α (hypoxia-inducible factor-1α) and p-STAT3 even under the normoxic conditions compared to the non-transfected cells. The HIF-1α and p-STAT3 expressions were increased several fold when the cells were subjected to hypoxic conditions. The HIF-1α and p-STAT3 protein expressions observed in HDM2 transfected LNCaP-MST cells were 20 and 15 folds higher, respectively, compared to the non-transfected wild-type LNCaP cells. These results demonstrate that HDM2 may have an important regulatory role in mediating the HIF-1α and p-STAT3 protein expression during both normoxic and hypoxic conditions. Furthermore, the vascular endothelial growth factor (VEGF) expression that is typically regulated by HIF-1α and p-STAT3 was also increased significantly by 136% (P < 0.01) after HDM2 transfection. The overall results point towards a novel ability of HDM2 in regulating HIF-1α and p-STAT3 levels even in normoxic conditions that eventually lead to an up-regulation of VEGF expression.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias da Próstata/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Fator de Transcrição STAT3/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Hipóxia Celular , Linhagem Celular Tumoral , Proliferação de Células , Forma Celular , Humanos , Masculino , Neoplasias da Próstata/patologia , Transfecção
19.
Biomedicines ; 10(6)2022 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-35740335

RESUMO

Estrogen promotes the development and survival of the majority of breast cancers (BCs). Aromatase is the rate-limiting enzyme in estrogen biosynthesis, and it is immensely expressed in both cancerous and non-cancerous breast tissues. Endocrine therapy based on estrogen blockade, by aromatase inhibitors, has been the mainstay of BC treatment in post-menopausal women; however, resistance to hormone therapy is the leading cause of cancer death. An improved understanding of the molecular underpinnings is the key to develop therapeutic strategies for countering the most prevalent hormone receptor positive BCs. Of note, cholesterol is the precursor of all steroid hormones that are synthesized in a variety of tissues and play crucial roles in diverse processes, ranging from organogenesis to homeostasis to carcinogenesis. The rate-limiting step in steroid biosynthesis is the transport of cholesterol from the outer to the inner mitochondrial membrane, a process that is primarily mediated by the steroidogenic acute regulatory (StAR) protein. Advances in genomic and proteomic technologies have revealed a dynamic link between histone deacetylases (HDACs) and StAR, aromatase, and estrogen regulation. We were the first to report that StAR is abundantly expressed, along with large amounts of 17ß-estradiol (E2), in hormone-dependent, but not hormone-independent, BCs, in which StAR was also identified as a novel acetylated protein. Our in-silico analyses of The Cancer Genome Atlas (TCGA) datasets, for StAR and steroidogenic enzyme genes, revealed an inverse correlation between the amplification of the StAR gene and the poor survival of BC patients. Additionally, we reported that a number of HDAC inhibitors, by altering StAR acetylation patterns, repress E2 synthesis in hormone-sensitive BC cells. This review highlights the current understanding of molecular pathogenesis of BCs, especially for luminal subtypes, and their therapeutics, underlining that StAR could serve not only as a prognostic marker, but also as a therapeutic candidate, in the prevention and treatment of this life-threatening disease.

20.
Front Genet ; 13: 942713, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36226173

RESUMO

Immunocompromised patients can experience prolonged SARS-CoV-2 infections in the setting of a lack of protectivity immunity despite vaccination. As circulating SARS-CoV-2 strains become more heterogeneous, concomitant infection with multiple SARS-CoV-2 variants has become an increasing concern. Immunocompromised patient populations represent potential reservoirs for the emergence of novel SARS-CoV-2 variants through mutagenic change or coinfection followed by recombinatory events. Identification of SARS-CoV-2 coinfections is challenging using traditional next generation sequencing pipelines; however, targeted genotyping approaches can facilitate detection. Here we describe five COVID-19 cases caused by coinfection with different SARS-CoV-2 variants (Delta/Omicron BA.1 and Omicron BA.1/BA.2) as identified by multiplex fragment analysis.

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