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1.
Cureus ; 15(4): e37904, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37220446

RESUMO

There are many presentations of iron-deficiency anemia associated with pica in adults, but there is a lack of literature summarizing its different presentations. In this scoping review, we sought to identify the various presentations and if treatment of iron-deficiency anemia resolved the presenting symptoms of pica. This review was conducted by completing the Preferred Reporting Items for Systematic Review and Meta-Analysis extension for Scoping Reviews (PRISMA-Scr) checklist. The following electronic databases were searched for potentially eligible articles: PubMed, ProQuest, and Bielefeld Academic Search Engine (BASE). Study screening procedures were completed with a narrative synthesis. The data is synthesized and interpreted by sifting, charting, and sorting based on organ systems. Twenty articles met the inclusion criteria and were included in the scoping review. Regardless of other clinical presentations, the identification of pica symptoms allowed treatment for iron deficiency and led to the resolution of all symptoms in all 20 articles. Therefore, it is imperative to map the available evidence to inform clinicians and allow for better patient care.

2.
Cureus ; 14(4): e23848, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35402117

RESUMO

Clinical and laboratory studies have shown that environmental exposure to cadmium produces damage to several organs, including bones, lungs, and kidneys. The involvement of cadmium in central nervous system (CNS) disorders has also been widely reported, but the precise pathophysiological mechanism is not yet fully understood. Children who were exposed to cadmium during pregnancy are known to suffer from developmental delays, learning difficulties, attention deficit hyperactivity disorder (ADHD), and other cognitive and neurobehavioral deficits. Results from numerous studies suggest that dysfunction of the blood-brain barrier (BBB) structures is an important step in the neurotoxicity of cadmium. A rat-specific BBB marker protein, the endothelial barrier antigen (EBA), has been previously isolated and classified by Sternberger and others. The mouse IgG1 clone, anti-endothelial barrier antigen (anti-EBA), detects a protein triplet (23.5kDa, 25 kDa, and 30kDa) localized to the luminal surface of central and peripheral nervous system (CNS and PNS) vascular endothelial cells with selective permeability barrier functions. This marker has been widely used for characterizing BBB alterations under demyelinating, inflammatory, and other CNS pathologies. Many studies have been published using the rat model system for studying the neurotoxic effect of acute and chronic exposure to cadmium. We applied the indirect immunofluorescent techniques using the anti-EBA antibody in conjunction with the Olympus cellSens computerized image analysis to detect and quantify the surface areas of BBB-competent microvessel profiles in paraformaldehyde-fixed, paraffin-embedded brains of term-delivered young rats after intraperitoneal injection of a single dose of cadmium chloride. We detected a statistically significant reduction in EBA-positive microvessel surface areas in the forebrain (t = 5.86, df = 1789, p-value < 0.001) and cerebellum (t=73.40, df=1337, p < 0.001) of cadmium-treated rats compared to the normal controls. Thus, this study supports the hypothesis that the EBA is a sensitive and measurable indicator for quantitative assessment of the impact of cadmium exposure in the developing rat brain.

3.
Cureus ; 14(12): e32175, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36605064

RESUMO

Military members, along with their injuries and expectations to return to duty, vary significantly from the general population. The purpose of this scoping review is to examine current literature pertaining to ankle injuries in United States military members and identify the research gaps. A scoping review was carried out with the PRISMA-ScR guidelines. A systematic search was utilized on three databases: PubMed, AMED, and Cochrane Library. The papers included were those of ankle injuries in the military. Exclusionary criteria included papers that did not have quantitative data, no full paper availability and non-US military. One hundred and fifty articles were screened, with nine meeting the inclusion criteria. Almost all of these were cohort by design. The focus was on a variety of tests for returning to active duty and the risks associated with individual factors for each service member. The study identified a lack of randomized control trials, underrepresentation of vulnerable subgroups within the US military, and no single test for ankle mobility and strength to return to duty. Prioritizing these deficiencies may help to save time and money within the US military healthcare system.

4.
Cureus ; 12(9): e10196, 2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-33033674

RESUMO

Acute respiratory distress syndrome (ARDS) is a potentially fatal lung injury that can present with divergent underlying cause across cases. Current treatment options are limited by an incomplete understanding of the disease sequelae, undefined unifying pathology, and lack of reliable diagnostic tools. ARDS is defined as respiratory failure not caused by fluid overload or cardiac failure within one week of a known clinical insult with bilateral opacities on chest imaging, and diagnosis is based on these parameters. Increased understanding of the inflammatory cascade associated with ARDS progression shows promise for identifying potential diagnostic biomarkers and additional treatment options. Here, we review recent studies that point to the unifying inflammatory element(s) of the disease process and the use of agents that decrease inflammation as potentially powerful treatments for ARDS patients.

5.
Pulm Circ ; 8(1): 2045893217753156, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29283027

RESUMO

Pulmonary endothelial cells express a store-operated calcium entry current ( Isoc), which contributes to inter-endothelial cell gap formation. Isoc is regulated by a heterocomplex of proteins that includes the immunophilin FKBP51. FKBP51 inhibits Isoc by mechanisms that are not fully understood. In pulmonary artery endothelial cells (PAECs) we have shown that FKBP51 increases microtubule polymerization, an event that is critical for Isoc inhibition by FKBP51. In neurons, FKBP51 promotes microtubule stability through facilitation of tau dephosphorylation. However, FKBP51 does not possess phosphatase activity. Protein phosphatase 5 (PP5C/PPP5C) can dephosphorylate tau, and similar to FKBP51, PP5C possesses tetratricopeptide repeats (TPR) that mediate interaction with heat shock protein-90 (HSP90) chaperone/scaffolding complexes. We therefore tested whether PP5C contributes to FKBP51-mediated inhibition of Isoc. Both siRNA-mediated suppression of PP5C expression in PAECs and genetic disruption of PP5C in HEK293 cells attenuate FKBP51-mediated inhibition of Isoc. Reintroduction of catalytically competent, but not catalytically inactive PP5C, restored FKBP51-mediated inhibition of Isoc. PAEC cell fractionation studies identified both PP5C and the ISOC heterocomplex in the same membrane fractions. Further, PP5C co-precipitates with TRPC4, an essential subunit of ISOC channel. Finally, to determine if PP5C is required for FKBP51-mediated inhibition of calcium entry-induced inter-endothelial cell gap formation, we measured gap area by wide-field microscopy and performed biotin gap quantification assay and electric cell-substrate impedance sensing (ECIS®). Collectively, the data presented indicate that suppression of PP5C expression negates the protective effect of FKBP51. These observations identify PP5C as a novel member of the ISOC heterocomplex that is required for FKBP51-mediated inhibition of Isoc.

6.
Pulm Circ ; 8(1): 2045893217749987, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29261039

RESUMO

Pulmonary artery endothelial cells (PAECs) express a cation current, ISOC (store-operated calcium entry current), which when activated permits calcium entry leading to inter-endothelial cell gap formation. The large molecular weight immunophilin FKBP51 inhibits ISOC but not other calcium entry pathways in PAECs. However, it is unknown whether FKBP51-mediated inhibition of ISOC is sufficient to protect the endothelial barrier from calcium entry-induced disruption. The major objective of this study was to determine whether FKBP51-mediated inhibition of ISOC leads to decreased calcium entry-induced inter-endothelial gap formation and thus preservation of the endothelial barrier. Here, we measured the effects of thapsigargin-induced ISOC on the endothelial barrier in control and FKBP51 overexpressing PAECs. FKBP51 overexpression decreased actin stress fiber and inter-endothelial cell gap formation in addition to attenuating the decrease in resistance observed with control cells using electric cell-substrate impedance sensing. Finally, the thapsigargin-induced increase in dextran flux was abolished in FKBP51 overexpressing PAECs. We then measured endothelial permeability in perfused lungs of FKBP51 knockout (FKBP51-/-) mice and observed increased calcium entry-induced permeability compared to wild-type mice. To begin to dissect the mechanism underlying the FKBP51-mediated inhibition of ISOC, a second goal of this study was to determine the role of the microtubule network. We observed that FKBP51 overexpressing PAECs exhibited increased microtubule polymerization that is critical for inhibition of ISOC by FKBP51. Overall, we have identified FKBP51 as a novel regulator of endothelial barrier integrity, and these findings are significant as they reveal a protective mechanism for endothelium against calcium entry-induced disruption.

7.
Pulm Circ ; 4(1): 116-27, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25006427

RESUMO

Disruption of the endothelium leads to increased permeability, allowing extravasation of macromolecules and other solutes from blood vessels. Calcium entry through a calcium-selective, store-operated calcium (SOC) channel, I soc, contributes to barrier disruption. An understanding of the mechanisms surrounding the regulation of I soc is far from complete. We show that the calcium/calmodulin-activated phosphatase calcineurin (CN) plays a role in regulation of SOC entry, possibly through the dephosphorylation of stromal interaction molecule 1 (STIM1). Phosphorylation has been implicated as a regulatory mechanism of activity for a number of canonical transient receptor potential (TRPC) and SOC channels, including I soc. Our results show that STIM1 phosphorylation increases in pulmonary artery endothelial cells (PAECs) upon activation of SOC entry. However, the phosphatases involved in STIM1 dephosphorylation are unknown. We found that a CN inhibitor (calcineurin inhibitory peptide [CIP]) increases the phosphorylation pattern of STIM1. Using a fura 2-acetoxymethyl ester approach to measure cytosolic calcium in PAECs, we found that CIP decreases SOC entry following thapsigargin treatment in PAECs. Luciferase assays indicate that thapsigargin induces activation of CN activity and confirm inhibition of CN activity by CIP in PAECs. Also, I soc is significantly attenuated in whole-cell patch-clamp studies of PAECs treated with CIP. Finally, PAECs pretreated with CIP exhibit decreased interendothelial cell gap formation in response to thapsigargin-induced SOC entry, as compared to control cells. Taken together, our data show that CN contributes to the phosphorylation status of STIM1, which is important in regulation of endothelial SOC entry and I soc activity.

8.
Cell Calcium ; 53(4): 275-85, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23375350

RESUMO

Calcium entry from the extracellular space into cells is an important signaling mechanism in both physiological and pathophysiological functions. In non-excitable cells, store-operated calcium (SOC) entry represents a principal mode of calcium entry. Activation of SOC entry in pulmonary artery endothelial cells leads to the formation of inter-endothelial cell gaps and subsequent endothelial barrier disruption. Regulation of endothelial SOC entry is poorly understood. In this work, we identify two large molecular weight immunophilins, FKBP51 and FKBP52, as novel regulators of SOC entry in endothelial cells. Using cell fractionation studies and immunocytochemistry we determined that a fraction of these largely cytosolic proteins localize to the plasma membrane where SOC entry channels are found. That FKBP51 and FKBP52 associate with SOC entry channel protein complexes was supported by co-precipitation of the immunophilins with TRPC4, a subunit of the calcium-selective, SOC entry channel ISOC. Dexamethasone-induced upregulation of FKBP51 expression in pulmonary artery endothelial cells reduced global SOC entry as well as ISOC. Similar results were observed when FKBP51 was over-expressed in an inducible HEK293 cell line. On the other hand, when FKBP52 was over-expressed SOC entry was enhanced. When expression of FKBP52 was inhibited, SOC entry was decreased. Collectively, our observations support regulatory roles for these large molecular weight immunophilins in which FKBP51 inhibits, whereas FKBP52 enhances, SOC entry in endothelial cells.


Assuntos
Cálcio/metabolismo , Proteínas de Ligação a Tacrolimo/metabolismo , Células Cultivadas , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Células HEK293 , Humanos , RNA Interferente Pequeno/farmacologia , Proteínas de Ligação a Tacrolimo/antagonistas & inibidores , Proteínas de Ligação a Tacrolimo/biossíntese
9.
Gen Comp Endocrinol ; 170(3): 514-21, 2011 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-21130091

RESUMO

Pituitary gonadotropins LH and FSH play central roles in reproductive function. In Old World primates, LH stimulates ovulation in females and testosterone production in males. Recent studies have found that squirrel monkeys and other New World primates lack expression of LH in the pituitary. Instead, chorionic gonadotropin (CG), which is normally only expressed in the placenta of Old World primates, is the active luteotropic pituitary hormone in these animals. The goal of this study was to investigate the tissue-specific regulation of squirrel monkey CG. We isolated the squirrel monkey CGß gene and promoter from genomic DNA from squirrel monkey B-lymphoblasts and compared the promoter sequence to that of the common marmoset, another New World primate, and human and rhesus macaque CGß and LHß. Using reporter gene assays, we found that a squirrel monkey CGß promoter fragment (-1898/+9) is active in both mouse pituitary LßT2 and human placenta JEG3 cells, but not in rat adrenal PC12 cells. Furthermore, within this construct separate cis-elements are responsible for pituitary- and placenta-specific expression. Pituitary-specific expression is governed by Egr-1 binding sites in the proximal 250 bp of the promoter, whereas placenta-specific expression is controlled by AP-2 sites further upstream. Thus, selective expression of the squirrel monkey CGß promoter in pituitary and placental cells is governed by distinct cis-elements that exhibit homology with human LHß and marmoset CGß promoters, respectively.


Assuntos
Gonadotropina Coriônica/metabolismo , Hipófise/metabolismo , Animais , Sequência de Bases , Gonadotropina Coriônica/genética , Feminino , Humanos , Camundongos , Células PC12 , Placenta/metabolismo , Gravidez , Ratos , Saimiri , Alinhamento de Sequência , Distribuição Tecidual
10.
Gen Comp Endocrinol ; 170(3): 509-13, 2011 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-21095191

RESUMO

Secretogranin II (SgII) is a member of the granin family of proteins found in neuroendocrine and endocrine cells. The expression and storage of SgII in the pituitary gland of Old World primates and rodents have been linked with those of luteinizing hormone (LH). However, New World primates including squirrel monkeys do not express LH in the pituitary gland, but rather CG is expressed. If CG takes on the luteotropic role of LH in New World primates, SgII may be associated with the expression and storage of CG in the pituitary gland. The goal of this study was to evaluate the regulation and distribution of CG and SgII in the squirrel monkey. A DNA fragment containing approximately 750 bp of squirrel monkey SgII promoter was isolated from genomic DNA and found to contain a cyclic-AMP response element that is also present in the human SgII promoter and important for GnRH responsiveness. The squirrel monkey and human SgII promoters were similarly activated by GnRH in luciferase reporter gene assays in LßT2 cells. Double immunofluorescence microscopy demonstrated close association of SgII and CG in gonadotrophs of squirrel monkey pituitary gland. These results suggest that CG and SgII have a similar intercellular distribution and are coregulated in squirrel monkey pituitary gland.


Assuntos
Gonadotropina Coriônica/genética , Hipófise/metabolismo , Secretogranina II/genética , Sequência de Aminoácidos , Animais , Gonadotropina Coriônica/biossíntese , Hormônio Liberador de Gonadotropina/fisiologia , Humanos , Dados de Sequência Molecular , Regiões Promotoras Genéticas/genética , Saimiri , Secretogranina II/biossíntese , Alinhamento de Sequência
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