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1.
Biotechnol J ; 18(10): e2300173, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37337924

RESUMO

Magnetosomes are magnetite nanoparticles biosynthesized by magnetotactic bacteria. Given their potential clinical applications for the diagnosis and treatment of cancer, it is essential to understand what becomes of them once they are within the body. With this aim, here we have followed the intracellular long-term fate of magnetosomes in two cell types: cancer cells (A549 cell line), because they are the actual target for the therapeutic activity of the magnetosomes, and macrophages (RAW 264.7 cell line), because of their role at capturing foreign agents. It is shown that cells dispose of magnetosomes using three mechanisms: splitting them into daughter cells, excreting them to the surrounding environment, and degrading them yielding less or non-magnetic iron products. A deeper insight into the degradation mechanisms by means of time-resolved X-ray absorption near-edge structure (XANES) spectroscopy has allowed us to follow the intracellular biotransformation of magnetosomes by identifying and quantifying the iron species occurring during the process. In both cell types there is a first oxidation of magnetite to maghemite and then, earlier in macrophages than in cancer cells, ferrihydrite starts to appear. Given that ferrihydrite is the iron mineral phase stored in the cores of ferritin proteins, this suggests that cells use the iron released from the degradation of magnetosomes to load ferritin. Comparison of both cellular types evidences that macrophages are more efficient at disposing of magnetosomes than cancer cells, attributed to their role in degrading external debris and in iron homeostasis.


Assuntos
Magnetossomos , Neoplasias , Magnetossomos/química , Ferro/metabolismo , Ferritinas/análise , Ferritinas/metabolismo , Macrófagos/metabolismo , Neoplasias/metabolismo
2.
J Hosp Med ; 17(12): 961-966, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36330542

RESUMO

BACKGROUND: Reducing unnecessary routine laboratory testing is a Choosing Wisely® recommendation, and new areas of overuse were noted during the COVID-19 pandemic. OBJECTIVE: To reduce unnecessary repetitive routine laboratory testing for patients with COVID-19 during the pandemic across a large safety net health system. DESIGNS, SETTINGS AND PARTICIPANTS: This quality improvement initiative was initiated by the System High-Value Care Council at New York City Health + Hospitals (H + H), the largest public healthcare system in the United States consisting of 11 acute care hospitals. INTERVENTION: four overused laboratory tests in noncritically ill hospitalized patients with COVID-19 were identified: C-reactive protein (CRP), ferritin, lactate dehydrogenase (LDH), and procalcitonin. A two-pronged electronic health record intervention was implemented consisting of (1) nonintrusive, informational nudge statements placed on selected order sets, and (2) a forcing function of one consecutive day limit on ordering. MAIN OUTCOME AND MEASURES: The average of excess tests per encounter days (ETPED) for each of four target laboratory testing only in patients with COVID-19. OBJECTIVE: Interdisciplinary System High-Value Care Council identified four overused laboratory tests (inflammatory markers) in noncritically ill hospitalized patients with COVID-19: C-reactive protein (CRP), ferritin, lactate dehydrogenase (LDH), and procalcitonin. Within an 11-hospital safety net health system, a two-pronged electronic health record intervention was implemented consisting of (1) nonintrusive, informational nudge statements placed on selected order sets, and (2) a forcing function of one consecutive day limit on ordering. The preintervention period (March 16, 2020 to January 24, 2021) was compared to the postintervention period (January 25, 2021 to March 22, 2022). RESULTS: Time series linear regression showed decreases in CRP (-17.9%, p < .05), ferritin (-37.6%, p < .001), and LDH (-30.1%, p < .001). Slope differences were significant (CRP, ferritin, and LDH p < 0.001; procalcitonin p < 0.05). Decreases were observed across weekly averages: CRP (-19%, p < .01), ferritin (-37.9%, p < .001), LDH (-28.7%, p < .001), and procalcitonin (-18.4%, p < .05). CONCLUSION: This intervention was associated with reduced routine inflammatory marker testing in non-intensive care unit COVID-19 hospitalized patients across 11 hospitals. Variation was high among individual hospitals.


Assuntos
COVID-19 , Testes Diagnósticos de Rotina , Procedimentos Desnecessários , Humanos , Biomarcadores/análise , Proteína C-Reativa/análise , Ferritinas/análise , L-Lactato Desidrogenase/análise , Pandemias , Pró-Calcitonina/análise , Procedimentos Desnecessários/estatística & dados numéricos , Testes Diagnósticos de Rotina/estatística & dados numéricos , Cidade de Nova Iorque
3.
Bratisl Lek Listy ; 123(6): 395-400, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35576540

RESUMO

OBJECTIVES: COVID-19 maintains its seriousness as a global emergency with its rapid distribution worldwide. Ferritin / lymphocyte percentage ratio (FLPR) may appear as a prognostic value at the initial evaluation stage and thus can be used as a simple, effective, and reliable parameter in critical patient identification with COVID-19. METHODS: In this retrospective cohort study, we evaluated patients over 18 years old, who were hospitalized after being evaluated as COVID-19 and whose PCR results were positive. We calculated FLPRs from complete blood counts taken during emergency department admissions and classified disease severity due to emergency initial evaluation. The relationship between the severity of the thoracic tomography findings, hospitalization, and intensive care needs, and 28-day mortality with the FLPR were evaluated. RESULTS: The difference between the groups classified according to COVID-19 severity and the FLPR means was statistically significant (x2=148.284; SD=3; p=0.000). FLPR levels were found to be high in critical and serious groups. In the ROC analysis for the FLPR level, the area under the curve (AUC) value was found to be 0.909 (95% CI 0.857-0.961). When the cut off value of FLPR was 9.80, the sensitivity was found to be 97.6 %, and the specificity was 65.2 %, whereas, when the cut off value for FLPR was found to be 21.11, the sensitivity was 82.9 % and the specificity was 82.8 %. CONCLUSION: The FLPR, a new parameter, can be used as a significant marker to predict the 28-day mortality in patients (Tab. 5, Fig. 1, Ref. 25).


Assuntos
COVID-19 , Ferritinas , Linfócitos , COVID-19/diagnóstico , Ferritinas/análise , Humanos , Prognóstico , Curva ROC , Estudos Retrospectivos
4.
PLoS One ; 17(3): e0265089, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35259196

RESUMO

BACKGROUND: Peru is the country with the world's highest COVID-19 death rate per capita. Characteristics associated with increased mortality among adult patients with COVID-19 pneumonia in this setting are not well described. METHODS: Retrospective, single-center cohort study including 1537 adult patients hospitalized with a diagnosis of SARS-CoV-2 pneumonia between May 2020 and August 2020 at a national hospital in Lima, Peru. The primary outcome measure was in-hospital mortality. RESULTS: In-hospital mortality was 49.71%. The mean age was 60 ± 14.25 years, and 68.38% were males. We found an association between mortality and inflammatory markers, mainly leukocytes, D-dimer, lactate dehydrogenase, C-reactive protein and ferritin. A multivariate model adjusted for age, hypertension, diabetes mellitus, and corticosteroid use demonstrated that in-hospital mortality was associated with greater age (RR: 2.01, 95%CI: 1.59-2.52) and a higher level of oxygen requirement (RR: 2.77, 95%CI: 2.13-3.62). Conclusions: In-hospital mortality among COVID-19 patients in Peru is high and is associated with greater age and higher oxygen requirements.


Assuntos
COVID-19/mortalidade , Hospitalização/estatística & dados numéricos , Fatores Etários , Idoso , Proteína C-Reativa/análise , COVID-19/diagnóstico , COVID-19/epidemiologia , COVID-19/virologia , Comorbidade , Feminino , Ferritinas/análise , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Peru/epidemiologia , Respiração Artificial , Estudos Retrospectivos , Fatores de Risco , SARS-CoV-2/isolamento & purificação
5.
Respirology ; 27(6): 427-436, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35176813

RESUMO

BACKGROUND AND OBJECTIVE: Inhalation of high concentrations of respirable crystalline silica (RCS) can lead to silicosis. RCS contains varying levels of iron, which can cause oxidative stress and stimulate ferritin production. This study evaluated iron-related and inflammatory markers in control and silicosis patients. METHODS: A cohort of stone benchtop industry workers (n = 18) were radiologically classified by disease severity into simple or complicated silicosis. Peripheral blood and bronchoalveolar lavage (BAL) were collected to measure iron, ferritin, C-reactive protein, serum amyloid A and serum silicon levels. Ferritin subunit expression in BAL and transbronchial biopsies was analysed by reverse transcription quantitative PCR. Lipid accumulation in BAL macrophages was assessed by Oil Red O staining. RESULTS: Serum iron levels were significantly elevated in patients with silicosis, with a strong positive association with serum ferritin levels. In contrast, markers of systemic inflammation were not increased in silicosis patients. Serum silicon levels were significantly elevated in complicated disease. BAL macrophages from silicosis patients were morphologically consistent with lipid-laden foamy macrophages. Ferritin light chain (FTL) mRNA expression in BAL macrophages was also significantly elevated in simple silicosis patients and correlated with systemic ferritin. CONCLUSION: Our findings suggest that elevated iron levels during the early phases of silicosis increase FTL expression in BAL macrophages, which drives elevated BAL and serum ferritin levels. Excess iron and ferritin were also associated with the emergence of a foamy BAL macrophage phenotype. Ferritin may represent an early disease marker for silicosis, where increased levels are independent of inflammation and may contribute to fibrotic lung remodelling.


Assuntos
Ferritinas , Silicose , Biomarcadores/metabolismo , Líquido da Lavagem Broncoalveolar/química , Ferritinas/análise , Ferritinas/metabolismo , Humanos , Inflamação/metabolismo , Ferro/análise , Ferro/metabolismo , Lipídeos , Pulmão/patologia , Macrófagos/metabolismo , Dióxido de Silício
6.
Am J Hematol ; 97(1): 60-67, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34710246

RESUMO

Iron deficiency anemia is associated with heavy menstrual bleeding (HMB) and, by extension, a bleeding disorder (BD). It is unknown if iron deficiency without anemia is associated with a BD in adolescents. Moreover, the threshold of ferritin associated with fatigue in adolescents with HMB is unclear. In this multicenter study, we enrolled adolescents with HMB without BD. Participants underwent BD and anemia work-up in Young Women's Hematology Clinics and completed the Peds QL™ fatigue scale. BDs were defined as von Willebrand Disease, platelet function defect, clotting factor deficiencies, and hypermobility syndrome. Two hundred and fifty consecutive adolescents were enrolled, of whom 196 met eligibility criteria. Overall, 43% (95% confidence interval: 36%-50%) were diagnosed with BD. A total of 61% (n = 119) had serum ferritin levels < 15 ng/mL, 23.5% (n = 46) had iron deficiency only, and 37% (n = 73) had iron deficiency anemia. Low ferritin or ferritin dichotomized as < 15 or ≥ 15 ng/mL was not associated with BD on univariable analysis (p = .24) or when accounting for age, race, ethnicity, body mass index, and hemoglobin (p = .35). A total of 85% had total fatigue score below the population mean of 80.5, and 52% (n = 102) were > 2 SD (or < 54) below the mean, the cut-off associated with severe fatigue. A ferritin threshold of < 6 ng/mL had a specificity of 79.8% but a sensitivity of 36% for severe fatigue. In conclusion, iron deficiency without anemia is not a predictor of BD in adolescents with HMB in a specialty setting. Severe fatigue, especially sleep fatigue, is prevalent in adolescents with BD. Ferritin of < 6 ng/mL has ~80% specificity for severe fatigue in adolescents with HMB.


Assuntos
Fadiga/complicações , Transtornos Hemorrágicos/complicações , Deficiências de Ferro/complicações , Adolescente , Adulto , Fadiga/sangue , Feminino , Ferritinas/análise , Transtornos Hemorrágicos/sangue , Humanos , Deficiências de Ferro/sangue , Masculino , Menorragia/sangue , Menorragia/complicações , Adulto Jovem , Doenças de von Willebrand/sangue , Doenças de von Willebrand/complicações
7.
Clin Pediatr (Phila) ; 61(1): 66-75, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34796723

RESUMO

Current screening guidelines may not be adequate to identify iron deficiency (ID) and iron deficiency anemia (IDA) in adolescent and young adults. Adolescent and young adult outpatients from 4 hospital-based clinics (N = 493) reported on diet, health, and bleeding, and had phlebotomy for iron and hematologic tests. We examined sex-specific factors associated with ID and IDA and ability of universal and risk factor-based screening using hemoglobin and hemoglobin plus ferritin to detect ID and IDA. Among females (n = 350), 34.6% had ID and 6.3% had IDA. Nearly 1 in 3 females with ID had no risk factors. Among males, 12.6% had ID; none had IDA. More than 1 in 3 males with ID did not have risk factors. Current screening approaches would have missed ID in 47% to 82% of females and 95% to 100% of males. ID was prevalent in both male and female adolescents and young adult outpatients. New approaches to screening for ID are needed to accurately evaluate iron status in this population.


Assuntos
Deficiências de Ferro/etiologia , Adolescente , Criança , Feminino , Ferritinas/análise , Ferritinas/sangue , Humanos , Deficiências de Ferro/epidemiologia , Masculino , Programas de Rastreamento/métodos , Programas de Rastreamento/estatística & dados numéricos , Prevalência , Fatores de Risco , Adulto Jovem
8.
Postgrad Med J ; 98(1162): 622-625, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33846221

RESUMO

PURPOSE OF THE STUDY: Elevated ferritin levels are associated with a variety of infectious, malignant and inflammatory diseases. We aimed to investigate the prognostic value of markedly elevated ferritin levels in hospitalised patients with various medical conditions. STUDY DESIGN: Retrospective analysis of patients with a ferritin level higher than 2000 ng/mL hospitalised in Sheba Medical Center between 1 January 2007 and 31 December 2015. Medical conditions of these patients were recorded. In-hospital, 30-day and 1-year mortality rates were evaluated according to ferritin ranges and clinical categories. RESULTS: The study included 722 patients (63.4% men) with a mean age of 63.9±16.7 years. The most common clinical conditions associated with markedly elevated ferritin were infectious diseases and malignancies. The highest mean ferritin levels were associated with rheumatological/inflammatory conditions (16 241.3 ng/dL), particularly in patients with macrophage activation syndrome (MAS) (96 615.5 ng/dL). In-hospital, 30-day and 1-year mortality rates were 32.3%, 46.7% and 70.8%, respectively. The highest in-hospital, 30-day and 1-year mortality rates were observed among patients with solid malignancies (40.1%, 64.7% and 90.3%, respectively), whereas the lowest rates were found among patients with rheumatological/inflammatory conditions, including MAS (21.4%, 38.1% and 45.2%, respectively). Ferritin levels were not associated with mortality. CONCLUSIONS: In hospitalised patients, ferritin levels higher than 2000 ng/mL are mainly associated with infectious and malignant diseases but do not predict mortality.


Assuntos
Ferritinas , Síndrome de Ativação Macrofágica , Neoplasias , Doenças Reumáticas , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Ferritinas/análise , Humanos , Síndrome de Ativação Macrofágica/complicações , Masculino , Pessoa de Meia-Idade , Neoplasias/complicações , Prognóstico , Estudos Retrospectivos , Doenças Reumáticas/complicações
9.
Sci Rep ; 11(1): 24224, 2021 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-34930966

RESUMO

Since 2019, a large number of people worldwide have been infected with severe acute respiratory syndrome coronavirus 2. Among those infected, a limited number develop severe coronavirus disease 2019 (COVID-19), which generally has an acute onset. The treatment of patients with severe COVID-19 is challenging. To optimize disease prognosis and effectively utilize medical resources, proactive measures must be adopted for patients at risk of developing severe COVID-19. We analyzed the data of COVID-19 patients from seven medical institutions in Tokyo and used mathematical modeling of patient blood test results to quantify and compare the predictive ability of multiple prognostic indicators for the development of severe COVID-19. A machine learning logistic regression model was used to analyze the blood test results of 300 patients. Due to the limited data set, the size of the training group was constantly adjusted to ensure that the results of machine learning were effective (e.g., recognition rate of disease severity > 80%). Lymphocyte count, hemoglobin, and ferritin levels were the best prognostic indicators of severe COVID-19. The mathematical model developed in this study enables prediction and classification of COVID-19 severity.


Assuntos
COVID-19/patologia , Modelos Teóricos , Adolescente , Adulto , Idoso , Proteína C-Reativa/análise , COVID-19/virologia , Feminino , Ferritinas/análise , Hemoglobinas/análise , Humanos , Contagem de Linfócitos , Aprendizado de Máquina , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Fatores de Risco , SARS-CoV-2/isolamento & purificação , Índice de Gravidade de Doença , Adulto Jovem
10.
Ann R Coll Surg Engl ; 103(8): 604-611, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34464565

RESUMO

INTRODUCTION: A novel hyperinflammatory syndrome has emerged in the paediatric population: paediatric inflammatory multisystem syndrome - temporally associated with SARS-CoV-2 (PIMS-TS). Up to 50% of patients develop shock with cardiac dysfunction but presentation with acute abdominal pain is common and difficult to distinguish from appendicitis. METHOD: Prospective case series of PIMS-TS patients presenting to a single UK tertiary paediatric centre. RESULTS: As of 16 September 2020, 89 patients have presented with PIMS-TS to our institution; 19 (21.3%) were referred for surgical review. Pyrexia and acute abdominal pain were seen in all 19 patients. Diarrhoea was reported in 14 (73%) and vomiting in 12 (63%). On examination, eight (42%) had right abdominal tenderness, of which five had right iliac fossa (RIF) peritonism. C-reactive protein (CRP) was universally raised: median 176 (15-463)mg/l. Abdominal imaging was performed in 17 (89%), with 11 undergoing abdominal ultrasonography (65%) and 8 abdominal computed tomography (47%); two required both. Findings included nonspecific features of inflammation in the RIF. Eight patients (42%) had an abnormal echocardiogram at admission. Two (10%) patients, with classical signs and symptoms of appendicitis, underwent appendicectomy without radiological imaging and were subsequently diagnosed with PIMS-TS. During the same period, 18 patients underwent appendicectomy for histologically confirmed appendicitis. Serum CRP and ferritin levels were significantly higher in the PIMS-TS cohort compared with children with appendicitis. CONCLUSIONS: PIMS-TS is a novel paediatric condition that may mimic appendicitis. It should be considered in patients presenting with abdominal pain to avoid unnecessary surgery in children at risk of cardiovascular instability.


Assuntos
COVID-19/diagnóstico , Síndrome de Resposta Inflamatória Sistêmica/diagnóstico , Adolescente , Apendicectomia , Apendicite/diagnóstico , Apendicite/cirurgia , Biomarcadores/sangue , Proteína C-Reativa/análise , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Ferritinas/análise , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Humanos , Lactente , Masculino , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Estudos Prospectivos
12.
Int J Mol Sci ; 22(16)2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34445190

RESUMO

Magnetite mineralization in human tissue is associated with various pathological processes, especially neurodegenerative disorders. Ferritin's mineral core is believed to be a precursor of magnetite mineralization. Magnetoferritin (MF) was prepared with different iron loading factors (LFs) as a model system for pathological ferritin to analyze its MRI relaxivity properties compared to those of native ferritin (NF). The results revealed that MF differs statistically significantly from NF, with the same LF, for all studied relaxation parameters at 7 T: r1, r2, r2*, r2/r1, r2*/r1. Distinguishability of MF from NF may be useful in non-invasive MRI diagnosis of pathological processes associated with iron accumulation and magnetite mineralization (e.g., neurodegenerative disorders, cancer, and diseases of the heart, lung and liver). In addition, it was found that MF samples possess very strong correlation and MF's relaxivity is linearly dependent on the LF, and the transverse and longitudinal ratios r2/r1 and r2*/r1 possess complementary information. This is useful in eliminating false-positive hypointensive artefacts and diagnosis of the different stages of pathology. These findings could contribute to the exploitation of MRI techniques in the non-invasive diagnosis of iron-related pathological processes in human tissue.


Assuntos
Apoferritinas/análise , Ferritinas/análise , Ferro/análise , Imageamento por Ressonância Magnética/métodos , Óxidos/análise , Animais , Cavalos , Humanos , Hidrodinâmica , Doenças Neurodegenerativas/diagnóstico
13.
Cell Tissue Res ; 386(2): 391-413, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34319433

RESUMO

All animals, other than Platyhelminthes, produce eggs containing yolk, referred to as "entolecithal" eggs. However, only Neoophora, in the phylum Platyhelminthes, produce "ectolecithal" eggs (egg capsules), in which yolk is stored in the vitelline cells surrounding oocytes. Vitelline cells are derived from vitellaria (yolk glands). Vitellaria are important reproductive organs that may be studied to elucidate unique mechanisms that have been evolutionarily conserved within Platyhelminthes. Currently, only limited molecular level information is available on vitellaria. The current study identified major vitellaria-specific proteins in a freshwater planarian, Dugesia ryukyuensis, using peptide mass fingerprinting (PMF) and expression analyses. Amino acid sequence analysis and orthology analysis via OrthoFinder ver.2.3.8 indicated that the identified major vitellaria-specific novel yolk ferritins were conserved in planarians (Tricladida). Because ferritins play an important role in Fe (iron) storage, we examined the metal elements contained in vitellaria and ectolecithal eggs, using non-heme iron histochemistry, elemental analysis based on inductively coupled plasma mass spectrometry and transmission electron microscopy- energy-dispersive X-ray spectroscopy analysis. Interestingly, vitellaria and egg capsules contained large amounts of aluminum (Al), but not Fe. The knockdown of the yolk ferritin genes caused a decrease in the volume of egg capsules, abnormality in juveniles, and increase in Al content in vitellaria. Yolk ferritins of D. ryukyuensis may regulate Al concentration in vitellaria via their pooling function of Al and protect the egg capsule production and normal embryogenesis from Al toxicity.


Assuntos
Alumínio/metabolismo , Proteínas do Ovo/metabolismo , Ferritinas/metabolismo , Proteínas de Helminto/metabolismo , Ferro/metabolismo , Planárias/metabolismo , Sequência de Aminoácidos , Animais , Proteínas do Ovo/análise , Proteínas do Ovo/genética , Ferritinas/análise , Ferritinas/genética , Proteínas de Helminto/análise , Proteínas de Helminto/genética , Óvulo/crescimento & desenvolvimento , Óvulo/metabolismo , Planárias/genética , Planárias/crescimento & desenvolvimento
14.
Arch Pediatr ; 28(6): 485-487, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34226064

RESUMO

Massive proteinuria in nephrotic syndrome causes depletion of various proteins. Iron deficiency can occur due to urinary loss of iron, transferrin, and soluble transferrin receptors. We conducted this cross-sectional study of 52 children with proteinuric nephrotic syndrome, aged 1-12 years (mean 7.1±2.7 years). Hemoglobin (Hb), RBC indices (MCV, MCH, MCHC), percentage of hypochromic RBCs (Hypo-He), reticulocyte hemoglobin content (Ret-He), and serum ferritin were examined. Seven (13%) patients had iron deficiency anemia and another 10 (19%) exhibited iron deficiency. A higher proportion of children with steroid-resistant disease had anemia than did steroid-sensitive children (P=0.076). Thus, children with nephrotic syndrome may have iron deficiency (32.7%), which needs to be screened.


Assuntos
Deficiências de Ferro/etiologia , Síndrome Nefrótica/complicações , Proteinúria/etiologia , Criança , Pré-Escolar , Estudos Transversais , Feminino , Ferritinas/análise , Ferritinas/sangue , Humanos , Deficiências de Ferro/fisiopatologia , Masculino , Síndrome Nefrótica/fisiopatologia , Projetos Piloto , Proteinúria/fisiopatologia , Transferrina/análise , Transferrina/metabolismo
15.
Ann Hematol ; 100(8): 1929-1946, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34155536

RESUMO

Extracellular vesicles (EVs) are bioactive, submicron-sized membrane vesicles released from all cell types upon activation or apoptosis. EVs including microparticles (MPs) and exosomes have emerged as important mediators of cell-to-cell communication in both normal and pathological states including thalassemia (thal). However, the role of EVs derived from ß-thal patients with iron overload (+ IO) and without iron overload (-IO) on cardiac cells is unclear. We hypothesized plasma EVs in thal patients containing ferritin (iron storage protein) and a denaturated hemoglobin-hemichrome that induce cardiac cell proliferation. The origins and numbers of EVs isolated from plasma of normal, thal (+ IO), and (- IO) patients were compared and determined for their iron and iron-containing proteins along with their effects on cardiac and endothelial cells. Data shows that MPs were originated from many cell sources with marked numbers of platelet origin. Only the number of RBC-derived MPs in thal (+ IO) patients was significantly high when compared to normal controls. Although MPs derived from both normal and thal patients promoted cardiac cell proliferation in a dose-dependent manner, only exosomes from thal patients promoted cardiac cell proliferation compared to the untreated. Moreover, the exosomes from thal (+ IO) potentially induce higher cardiac cell proliferation and angiogenesis in terms of tube number than thal (- IO) and normal controls. Interestingly, ferritin content in the exosomes isolated from thal (+ IO) was higher than that found in the MPs isolated from the same patient. The exosomes of thal patients with higher serum ferritin level also contained greater level of ferritin inside the exosomes. Apart from ferritin, there were trends of increasing hemichrome and iron presented in the plasma EVs and EV-treated H9C2 cells. Findings from this study support the hypothesis that EVs from ß-thal patients carry iron-load proteins that leads to the induction of cardiac cell proliferation.


Assuntos
Vesículas Extracelulares/patologia , Ferritinas/análise , Hemeproteínas/análise , Ferro/análise , Mioblastos Cardíacos/citologia , Talassemia/patologia , Adulto , Linhagem Celular , Proliferação de Células , Vesículas Extracelulares/metabolismo , Feminino , Ferritinas/metabolismo , Hemeproteínas/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Ferro/metabolismo , Masculino , Pessoa de Meia-Idade , Mioblastos Cardíacos/metabolismo , Talassemia/sangue , Talassemia/metabolismo , Adulto Jovem
16.
Nat Commun ; 12(1): 4026, 2021 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-34188052

RESUMO

Iron is essential for a healthy pregnancy, and iron supplementation is nearly universally recommended, regardless of maternal iron status. A signal of potential harm is the U-shaped association between maternal ferritin, a marker of iron stores, and risk of adverse pregnancy outcomes. However, ferritin is also induced by inflammation and may overestimate iron stores during inflammation or infection. In this study, we use mouse models to determine whether maternal iron loading, inflammation, or their interaction cause poor pregnancy outcomes. Only maternal exposure to both iron excess and inflammation, but not either condition alone, causes embryo malformations and demise. Maternal iron excess potentiates embryo injury during both LPS-induced acute inflammation and obesity-induced chronic mild inflammation. The adverse interaction depends on TNFα signaling, causes apoptosis of placental and embryo endothelium, and is prevented by anti-TNFα or antioxidant treatment. Our findings raise important questions about the safety of indiscriminate iron supplementation during pregnancy.


Assuntos
Apoptose/fisiologia , Ferritinas/análise , Ferro/metabolismo , Obesidade/patologia , Placenta/patologia , Animais , Células Cultivadas , Embrião de Mamíferos/patologia , Feminino , Hepcidinas/genética , Células Endoteliais da Veia Umbilical Humana , Humanos , Ferro/toxicidade , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Gravidez , Complicações na Gravidez , Fator de Necrose Tumoral alfa/metabolismo
17.
Cells ; 10(5)2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-34064487

RESUMO

Liver injury in COVID-19 patients has progressively emerged, even in those without a history of liver disease, yet the mechanism of liver pathogenicity is still controversial. COVID-19 is frequently associated with increased serum ferritin levels, and hyperferritinemia was shown to correlate with illness severity. The liver is the major site for iron storage, and conditions of iron overload have been established to have a pathogenic role in development of liver diseases. We presented here six patients who developed severe COVID-19, with biochemical evidence of liver failure. Three cases were survived patients, who underwent liver biopsy; the other three were deceased patients, who were autopsied. None of the patients suffered underlying liver pathologies. Histopathological and ultrastructural analyses were performed. The most striking finding we demonstrated in all patients was iron accumulation into hepatocytes, associated with degenerative changes. Abundant ferritin particles were found enclosed in siderosomes, and large aggregates of hemosiderin were found, often in close contact with damaged mitochondria. Iron-caused oxidative stress may be responsible for mitochondria metabolic dysfunction. In agreement with this, association between mitochondria and lipid droplets was also found. Overall, our data suggest that hepatic iron overload could be the pathogenic trigger of liver injury associated to COVID-19.


Assuntos
COVID-19/diagnóstico , Sobrecarga de Ferro/etiologia , Falência Hepática/etiologia , Fígado/patologia , Índice de Gravidade de Doença , Adulto , Idoso , Antivirais , Biópsia , COVID-19/complicações , COVID-19/mortalidade , COVID-19/terapia , Feminino , Ferritinas/análise , Hepatócitos/citologia , Hepatócitos/patologia , Humanos , Ferro/análise , Ferro/metabolismo , Sobrecarga de Ferro/mortalidade , Sobrecarga de Ferro/patologia , Sobrecarga de Ferro/terapia , Fígado/citologia , Fígado/metabolismo , Falência Hepática/mortalidade , Falência Hepática/patologia , Falência Hepática/terapia , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Mitocôndrias/patologia , Respiração com Pressão Positiva , SARS-CoV-2/isolamento & purificação
18.
Neuroimage ; 239: 118255, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34119638

RESUMO

In Parkinson's disease, the depletion of iron-rich dopaminergic neurons in nigrosome 1 of the substantia nigra precedes motor symptoms by two decades. Methods capable of monitoring this neuronal depletion, at an early disease stage, are needed for early diagnosis and treatment monitoring. Magnetic resonance imaging (MRI) is particularly suitable for this task due to its sensitivity to tissue microstructure and in particular, to iron. However, the exact mechanisms of MRI contrast in the substantia nigra are not well understood, hindering the development of powerful biomarkers. In the present report, we illuminate the contrast mechanisms in gradient and spin echo MR images in human nigrosome 1 by combining quantitative 3D iron histology and biophysical modeling with quantitative MRI on post mortem human brain tissue. We show that the dominant contribution to the effective transverse relaxation rate (R2*) in nigrosome 1 originates from iron accumulated in the neuromelanin of dopaminergic neurons. This contribution is appropriately described by a static dephasing approximation of the MRI signal. We demonstrate that the R2* contribution from dopaminergic neurons reflects the product of cell density and cellular iron concentration. These results demonstrate that the in vivo monitoring of neuronal density and iron in nigrosome 1 may be feasible with MRI and provide directions for the development of biomarkers for an early detection of dopaminergic neuron depletion in Parkinson's disease.


Assuntos
Neurônios Dopaminérgicos/química , Ferro/análise , Imageamento por Ressonância Magnética/métodos , Substância Negra/citologia , Idoso de 80 Anos ou mais , Biofísica , Ferritinas/análise , Humanos , Masculino , Melaninas/análise , Pessoa de Meia-Idade , Modelos Neurológicos , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Software , Substância Negra/química
19.
Int J Lab Hematol ; 43(5): 1243-1251, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33939271

RESUMO

INTRODUCTION: Although factors such as age, sex, diabetes, obesity and changes in certain laboratory investigations are important prognostic factors in COVID-19 infection, these may not apply to all ethnic/racial groups. We hypothesized differences in routine biochemistry and haematology indices in Caucasian and a combined group of Black, Asian and Minority Ethnic (BAME) patients who tested positive for COVID-19 who died, compared to survivors. METHODS: We tested our hypothesis in 445 patients (229 Caucasian, 216 BAME) admitted to secondary care with proven COVID-19 infection, in whom standard routine laboratory indices were collected on admission. RESULTS: After 28 weeks, 190 (42.7%) had died within 28 days of COVID diagnosis (97 Caucasians [42.4%], 93 BAMEs [43.1%], P = .923). A general linear model analysis found the ethnicity interaction with mortality to be significant for fibrinogen, ferritin and HbA1 c (after controlling for age). In a multivariate analysis, a neutrophil/lymphocyte ratio > 7.4 and a urea/albumin ratio > 0.28 increased the odds of death for both the Caucasian and the BAME group. Additional factors increasing the odds ratio in the BAME group included age >60 years and being diabetic. CONCLUSION: Neutrophil/lymphocyte ratio and urea/albumin ratio are simple metrics that predict death to aid clinicians in determining the prognosis of COVID-19 and help provide early intensive intervention to reduce mortality. In the BAME groups, intensive monitoring even at younger age and those with diabetes may also help reduce COVID-19 associated mortality.


Assuntos
COVID-19/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/epidemiologia , Etnicidade , Feminino , Ferritinas/análise , Fibrinogênio/análise , Hemoglobinas Glicadas/análise , Humanos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , SARS-CoV-2/isolamento & purificação , Albumina Sérica Humana/análise , Ureia/sangue
20.
Transfusion ; 61(7): 2090-2098, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33913181

RESUMO

BACKGROUND: Pica is characterized as repeatedly eating or chewing a non-nutritious substance including, but not limited to ice, clay and dirt, starch, raw pasta, chalk, coal, paint, or paper. Pica symptoms can be intense and addiction-like and disrupt quality of life. It is strongly linked to iron deficiency. Since substantial iron loss occurs during blood donation, blood donors may be susceptible to development of pica behaviors. METHODS: We investigated demographic, clinical, hematological, and biochemical factors associated with pica using univariable and multivariable logistic regression analysis in a cohort of 11,418 racially diverse blood donors. Pica was defined by questionnaire responses as consuming at least 8 oz of ice daily and/or consumption of non-ice substances regardless of the amount and frequency. RESULTS: Pica was present in 2.2% of the donors. The sensitivity and specificity of pica in iron-deficient donors were 36% and 82%, respectively. Lower ferritin (p = .001), non-Asian race (p < .001), higher red cell distribution width (p < .001), younger age, and restless legs syndrome (p = .008) were independently associated with pica. Female sex is associated with iron deficiency but was not an independent predictor of pica suggesting that iron deficient males and females were equally susceptible to the development of pica behaviors. Donors with normal ferritin levels also reported pica, reinforcing the role of non-iron related factors in its presentation. CONCLUSIONS: We have identified demographic, clinical, and biochemical predictors of pica that help identify those most at risk for developing pica behaviors, and thereby assist in its clinical diagnosis and treatment.


Assuntos
Doadores de Sangue , Deficiências de Ferro , Pica/epidemiologia , Adolescente , Adulto , Biomarcadores , Contagem de Células Sanguíneas , Índice de Massa Corporal , Connecticut/epidemiologia , Suscetibilidade a Doenças , Índices de Eritrócitos , Etnicidade/estatística & dados numéricos , Comportamento Alimentar , Feminino , Ferritinas/análise , Humanos , Gelo , Masculino , Pessoa de Meia-Idade , Pennsylvania/epidemiologia , Pica/etiologia , Grupos Raciais/estatística & dados numéricos , Sensibilidade e Especificidade , Inquéritos e Questionários , Wisconsin/epidemiologia , Adulto Jovem
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