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1.
Amino Acids ; 56(1): 30, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607556

RESUMO

Walker-256 tumor is an experimental model known to promote cachexia syndrome, oxidative stress, and systemic inflammation. This study evaluated the duodenal mucosa of rats with Walker-256 tumor administered with 1% L-glutathione, intending to evaluate the damage caused by cancer-associated cachexia in the gastrointestinal tract and the effects of antioxidant administration on mucosal protection. Twenty-four 55-day-old male Wistar rats were distributed into four groups: control (C); control administered with 1% L-glutathione (C-GSH); Walker-256 tumor (W) and Walker-256 tumor administered with 1% L-glutathione (W-GSH). After 14 days of treatment, the duodenum was harvested for morphometric analysis of the mucosa, proliferation, apoptosis, immunostaining of varicosities immunoreactive (IR) to vasoactive intestinal peptide (VIP) and 5-HT-IR cells, and quantification of mast cells and goblet cells. Walker-256 tumor-bearing rats showed cachexia syndrome, mucosal atrophy, reduced cell proliferation, reduced 5-HT-IR cells, and increased goblet cells and VIPergic varicosities, which were not reversed by L-glutathione. On the other hand, L-glutathione caused a reduction of cells in apoptosis and mast cell recruitment, demonstrating a partial recovery of the damage detected in the intestinal mucosa.


Assuntos
Caquexia , Neoplasias , Masculino , Ratos , Animais , Caquexia/tratamento farmacológico , Serotonina , Ratos Wistar , Mucosa Intestinal , Glutationa
2.
Int J Mol Sci ; 25(16)2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39201333

RESUMO

Lysosomal acid lipase deficiency (LALD) varies from a severe infantile-onset form (Wolman disease) to a late-onset form known as cholesteryl ester storage disease (CESD), both of which are autosomal recessive disorders caused by biallelic LIPA pathogenic variants. We evaluated seventy-three patients enlisted for liver transplant (LT) at Instituto da Criança (HCFMUSP-Brazil) who were subjected to LAL activity measurement and LIPA Sanger sequencing analysis, resulting in a positive LALD diagnosis for only one of these individuals. This LALD patient presented recurrent diarrhea, failure to thrive, hepatomegaly, and dyslipidemia at the age of 4 months and liver failure by the age of 13 years. The LALD diagnosis confirmation was conducted at 24 years old due to low levels of LAL enzyme activity. The causal homozygous variant LIPA(NM_000235.4):c.266T>C(p.Leu89Pro) was identified, but the patient had already undergone his first LT at 18 years with several rejection episodes. Despite beginning treatment with sebelipase alfa at 26 years old (total of five infusions), this patient died at 28 years from complications after his second liver transplant. LALD is an important differential diagnosis in cases presenting with hepatomegaly, elevated liver enzymes, and dyslipidemia. Detecting low/absent LAL activity and identifying the LIPA causal variant are essential for diagnosis and specific treatment, as well as for appropriate genetic counseling. Early diagnosis, along with sebelipase alfa therapy, may improve the prognosis of affected patients.


Assuntos
Transplante de Fígado , Esterol Esterase , Doença de Wolman , Humanos , Doença de Wolman/genética , Doença de Wolman/diagnóstico , Masculino , Esterol Esterase/genética , Esterol Esterase/deficiência , Feminino , Adolescente , Lactente , Adulto , Pré-Escolar , Criança , Adulto Jovem
3.
Ann Hepatol ; 27(4): 100707, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35477031

RESUMO

INTRODUCTION: Although hyperferritinemia may reflect the inflammatory status of patients with non-alcoholic fatty liver disease (NAFLD), approximately 33% of hyperferritinemia cases reflect real hepatic iron overload. AIM: To evaluate a non-invasive method for assessing mild iron overload in patients with NAFLD using 3T magnetic resonance imaging (MRI) relaxometry, serum hepcidin, and the expression of ferritin subunits. METHODS: This cross-sectional study assessed patients with biopsy-proven NAFLD. MRI relaxometry was performed using a 3T scanner in all patients, and the results were compared with iron content determined by liver biopsy. Ferritin, hepcidin, and ferritin subunits were assessed and classified according to ferritin levels and to siderosis identified by liver biopsy. RESULTS: A total of 67 patients with NAFLD were included in the study. MRI revealed mild iron overload in all patients (sensitivity, 73.5%; specificity, 70%). For mild (grade 1) siderosis, the transverse relaxation rate (R2*) threshold was 58.9 s-1 and the mean value was 72.5 s-1 (SD, 33.9), while for grades 2/3 it was 88.2 s-1 (SD, 31.9) (p < 0.001). The hepcidin threshold for siderosis was > 30.2 ng/mL (sensitivity, 87%; specificity, 82%). Ferritin H and ferritin L subunits were expressed similarly in patients with NAFLD, regardless of siderosis. There were no significant differences in laboratory test results between the groups, including glucose parameters and liver function tests. CONCLUSIONS: MRI relaxometry and serum hepcidin accurately assessed mild iron overload in patients with dysmetabolic iron overload syndrome.


Assuntos
Hiperferritinemia , Sobrecarga de Ferro , Síndrome Metabólica , Hepatopatia Gordurosa não Alcoólica , Siderose , Estudos Transversais , Ferritinas , Hepcidinas , Humanos , Sobrecarga de Ferro/diagnóstico por imagem , Sobrecarga de Ferro/etiologia , Fígado/patologia , Síndrome Metabólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Siderose/metabolismo , Siderose/patologia
4.
Mult Scler ; 27(6): 973-976, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32909895

RESUMO

Neurologic complications are being recognized as important outcomes of coronavirus disease 2019 (COVID-19). Pathogenesis is varied and incompletely understood, and may include neuroinvasion, indirect post-infectious neuroinflammation, and cerebrovascular pathologies. We present a case of COVID-19-related encephalomyeloradiculitis with clinical and magnetic resonance imaging characteristics of neuromyelitis optica spectrum disorders that was associated with anti-aquaporin-4 antibodies. Our case suggests post-infectious autoimmunity as a mechanism in at least a subset of patients with COVID-19-related neurologic disease.


Assuntos
Aquaporina 4/imunologia , Autoanticorpos/análise , Doenças Autoimunes/etiologia , COVID-19/complicações , Encefalomielite/etiologia , Radiculopatia/etiologia , Azatioprina/uso terapêutico , Encéfalo/diagnóstico por imagem , COVID-19/diagnóstico por imagem , Encefalomielite/diagnóstico por imagem , Encefalomielite/imunologia , Feminino , Humanos , Imunossupressores/uso terapêutico , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Neuromielite Óptica/diagnóstico por imagem , Neuromielite Óptica/etiologia , Troca Plasmática , Radiculopatia/diagnóstico por imagem , Radiculopatia/imunologia , Coluna Vertebral/diagnóstico por imagem
5.
J Sep Sci ; 44(1): 438-447, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33090611

RESUMO

Urocanic acid is a chromophore found in the skin that has been identified as an important immunosuppressant and carcinogenesis mediator through its photoisomerization from trans to cis form induced by ultraviolet radiation. Research on analytical methods that explore urocanic acid isomerization is indispensable to fully understand the deleterious effects mediated by this biomarker. In this context, the current relevant analytical methods for determination of these isomers in human samples are summarized in this review. The methods presented here are applicable to human samples collected by noninvasive methods (or minimally invasive), encompassing an array of analytical techniques, including high-performance capillary electrophoresis, confocal Raman spectroscopy, gas chromatography, high-performance liquid chromatography, and mass spectrometry, among others. Developed high-performance liquid chromatography methods have proven to be advantageous, allowing noninvasive collections for in vivo analysis and the confocal Raman, specially, for real-time analysis. Among all these methods, high-performance liquid chromatography is the most investigated one with mass spectrometry or ultraviolet detector, and the mass spectrometry detector being the most studied in the last years, demonstrating high sensitivity, very low detection limits, and accurate identification, especially for clinical investigations.


Assuntos
Ácido Urocânico/análise , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Análise Espectral Raman
6.
Cultur Divers Ethnic Minor Psychol ; 27(4): 696-704, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34264708

RESUMO

Objectives: For many low-income, Latinx and Asian first-generation students, family is a central motivator for obtaining a college degree. Yet, striving for upward mobility yields unanticipated psychological consequences. Specifically, family achievement guilt is a socioemotional experience related to "leaving family" to attend college. As a relatively understudied phenomenon, prior work has likely underrepresented the ways low-income, Latinx and Asian first-generation students experience guilt in the university. To address this gap, the current study aimed to refine the concept of family achievement guilt by exploring its different facets. Method: We utilized in-depth, semistructured interviews with 34 low-income, Latinx and Asian first-generation students. Results: Using both inductive and deductive analytic methods, we constructed four facets of guilt. Participants shared feeling guilt related to leaving family behind, having more privileges in the university context, becoming culturally different than family members, and experiencing financial distress. Conclusions: Unpacking family achievement guilt experiences of a fast-growing student population contributes to our understanding of theory and of possible support mechanisms. (PsycInfo Database Record (c) 2021 APA, all rights reserved).


Assuntos
Logro , Estudantes , Escolaridade , Humanos , Pobreza , Universidades
7.
Int J Mol Sci ; 21(19)2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32992944

RESUMO

Magnesium (Mg2+) is an essential mineral for the functioning and maintenance of the body. Disturbances in Mg2+ intracellular homeostasis result in cell-membrane modification, an increase in oxidative stress, alteration in the proliferation mechanism, differentiation, and apoptosis. Mg2+ deficiency often results in inflammation, with activation of inflammatory pathways and increased production of proinflammatory cytokines by immune cells. Immune cells and others that make up the blood system are from hematopoietic tissue in the bone marrow. The hematopoietic tissue is a tissue with high indices of renovation, and Mg2+ has a pivotal role in the cell replication process, as well as DNA and RNA synthesis. However, the impact of the intra- and extracellular disturbance of Mg2+ homeostasis on the hematopoietic tissue is little explored. This review deals specifically with the physiological requirements of Mg2+ on hematopoiesis, showing various studies related to the physiological requirements and the effects of deficiency or excess of this mineral on the hematopoiesis regulation, as well as on the specific process of erythropoiesis, granulopoiesis, lymphopoiesis, and thrombopoiesis. The literature selected includes studies in vitro, in animal models, and in humans, giving details about the impact that alterations of Mg2+ homeostasis can have on hematopoietic cells and hematopoietic tissue.


Assuntos
Hematopoese , Células-Tronco Hematopoéticas , Deficiência de Magnésio , Magnésio , Animais , Diferenciação Celular , Linhagem Celular , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Homeostase , Humanos , Magnésio/farmacologia , Magnésio/fisiologia
8.
Genet Mol Biol ; 43(1): e20180370, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32105287

RESUMO

Biological dosimetry aims to estimate individual absorbed doses due ionizing radiation exposure. The dicentric chromosomes are considered the most specific biomarker for dose estimation. This study aimed to compare calibration curves for linear low energy transfer (LET) radiation built from low dose rates and whether they vary in terms of dose estimation. For that we did a search in the literature of all calibration curves produced with low dose rates and we simulated the dose estimation from pre-established dicentric's frequencies. The information on methodologies and cytogenetic results of each study were analyzed. As expected dose rate influence ß coefficients, especially at higher doses. However, we have seen that some doses were not statistically different but they should be, because there is a significant association between the productions of dicentrics and dose rate. This comparative study reinforced the robustness of the dicentric assay and its importance in biological dosimetry. We also emphasized that the dose rate was an important factor in dose estimations. Thus, intercomparison exercises should take into account the dose rates of the participating laboratories, because the dose rates might explain why some results of estimated doses fall outside the recommendations.

9.
Histopathology ; 75(5): 638-648, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31087672

RESUMO

AIMS: The clinical spectrum of yellow fever (YF) ranges from asymptomatic to fulminant hepatitis. During the sylvatic YF epidemic in the metropolitan area of São Paulo, Brazil in 2018, seven orthotopic liver transplantations (OLTs) were performed in our institution to treat fulminant YF hepatitis. Three patients recovered, while four patients died following OLT. The autopsy findings of all these cases are presented herein as the first description of YF in transplanted patients. METHODS AND RESULTS: All patients were men, aged 16-40 years, without vaccination to YF virus (YFV). All organs were examined, with tissue sampling for histopathological analysis. Detection of YF virus antigens (YFV Ag) was performed with two primary antibodies (mouse polyclonal anti-YFV antibody directed to wild strain and a goat anti-YF virus antibody), and RT-PCR assays were utilised to detect YFV-RNA. All the cases depicted typical findings of YF hepatitis in the engrafted liver. The main extrahepatic findings were cerebral oedema, pulmonary haemorrhage, pneumonia, acute tubular necrosis and ischaemic/reperfusion pancreatitis. Of the four cases, the YVF Ag was detected in the heart in one case, liver and testis in three cases, and the kidney and spleen in all four cases. All four cases had YF virus RNA detected by RT-PCR in the liver and in other organs. CONCLUSIONS: Infection of the engrafted liver and other organs by YFV, possibly combined with major ischaemic systemic lesions, may have led to the death of four of the seven patients undergoing OLT.


Assuntos
Transplante de Fígado , Necrose Hepática Massiva/virologia , Transplantes/virologia , Febre Amarela , Vírus da Febre Amarela , Adolescente , Adulto , Autopsia , Brasil , Humanos , Transplante de Fígado/mortalidade , Masculino , Febre Amarela/patologia , Febre Amarela/cirurgia , Febre Amarela/virologia , Adulto Jovem
11.
Curr Psychiatry Rep ; 17(5): 28, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25773224

RESUMO

Schizophrenia is a complex mental disorder associated with not only cognitive dysfunctions, such as memory and attention deficits, but also changes in basic sensory processing. Although most studies on schizophrenia have focused on disturbances in higher-order brain functions associated with the prefrontal cortex or frontal cortex, recent investigations have also reported abnormalities in low-level sensory processes, such as the visual system. At very early stages of the disease, schizophrenia patients frequently describe in detail symptoms of a disturbance in various aspects of visual perception that may lead to worse clinical symptoms and decrease in quality of life. Therefore, the aim of this review is to describe the various studies that have explored the visual issues in schizophrenia.


Assuntos
Movimentos Oculares , Retina/patologia , Esquizofrenia/patologia , Esquizofrenia/fisiopatologia , Vias Visuais/patologia , Vias Visuais/fisiopatologia , Percepção Visual , Convergência Ocular , Dopamina/metabolismo , Núcleo de Edinger-Westphal/patologia , Endofenótipos , Lobo Frontal/fisiopatologia , Glutamina/metabolismo , Humanos , Testes Neuropsicológicos , Córtex Pré-Frontal/fisiopatologia , Acompanhamento Ocular Uniforme , Qualidade de Vida , Movimentos Sacádicos , Esquizofrenia/metabolismo
12.
J Surg Res ; 189(2): 313-20, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-24721605

RESUMO

BACKGROUND: Ischemia-reperfusion injury is partly responsible for morbidity in pediatric liver transplantation. Large-for-size (LFS) liver transplantation has not been fully studied in the pediatric population, and the effects of reperfusion injury may be underestimated. MATERIALS AND METHODS: Thirteen Landrace-Large white pigs weighing 23 kg (range, 17-38 kg) underwent orthotopic liver transplantation. They were divided into two groups according to the size of the donor body: LFS and control (CTRL). After transplantation, the abdominal cavity of the recipient was kept open and portal venous flow (PVF) was measured after 1 h. The ratio of recipient PVF (PVFr) to donor PVF was used to establish correlations with ischemia and reperfusion parameters. Liver biopsies were taken 1 h after transplantation to assess ischemia and reperfusion and to quantify the gene expression of endothelial nitric oxide synthase, interleukin 6, BAX, and BCL. RESULTS: Recipient weight, total ischemia time, and warm ischemia time were similar between groups. Among hemodynamic and metabolic analyses, pH, central arteriovenous PCO2 difference, and AST were statistically worse in the LFS group than in the CTRL group. The same was found with endothelial nitric oxide synthase (0.41 ± 0.18 versus 1.56 ± 0.78; P = 0.02) and interleukin 6 (4.66 ± 4.61 versus 16.21 ± 8.25; P = 0.02). In the LFS group, a significant decay in the PVFr was observed in comparison with the CTRL group (0.93 ± 0.08 and 0.52 ± 0.11, respectively; P < 0.001). CONCLUSIONS: The implantation of a graft was responsible for poor hemodynamic status of the recipient 1 h after transplantation. Furthermore, the LFS group demonstrated markers of ischemia and reperfusion that were worse when compared with the CTRL group and exhibited a more significant decrease in PVF from donor to recipient.


Assuntos
Circulação Hepática , Transplante de Fígado/efeitos adversos , Traumatismo por Reperfusão/etiologia , Animais , Hemodinâmica , Fígado/enzimologia , Fígado/patologia , Tamanho do Órgão , Pediatria , Distribuição Aleatória , Suínos
13.
Acta Histochem ; 126(3): 152146, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38422841

RESUMO

Cancer-induced cachexia is associated with systemic inflammation and gastrointestinal dysfunction. How changes to cells of the enteric nervous system contribute to gut dysfunction in tumor development and cancer cachexia is unknown. Here, we tested the hypothesis that changes to enteric glia, a type of peripheral glia that surround enteric neurons and regulate gut homeostasis, are associated with tumor development and that supplementing with the antioxidant L-glutathione is protective against the changes induced. Immunohistochemistry for neurons, enteric glial cells and immune cells was performed in whole-mount preparations and frozen histological sections of the jejunum from 20 Wistar rats, distributed in 4 groups: control, tumor of Walker-256, control administered with 1 % L-glutathione, and tumor of Walker-256 administered with 1 % L-glutathione. Morphoquantitative analyses were made using Image-Pro® Plus 4.5 and ImageJ® 1.43° software. Tumor development significantly reduced neuronal and glial cell populations in the myenteric and submucosal plexuses and enlarged glial cell body area in the submucosal plexus. In contrast, tumors increased glia in the jejunal mucosa and this effect was accompanied by B-lymphocyte recruitment. GSH-supplemented diet was not sufficient to protect against changes to neurons and glia in the submucosal plexus but was partially protective in the myenteric plexus. L-glutathione had no effect on physiological parameters of cachexia but was sufficient to preserve enteric glial cell density in the myenteric plexus. These results suggest that changes to both enteric neurons and glia likely contribute to the gastrointestinal effects of tumor development and that oxidative stress contributes to these effects in the enteric nervous system.

14.
Int J Radiat Biol ; 100(7): 1019-1028, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38810111

RESUMO

PURPOSE: This interlaboratory comparison was conducted to evaluate the performance of the Latin-American Biodosimetry Network (LBDNet) in analyzing digitized images for scoring dicentric chromosomes from in vitro irradiated blood samples. The exercise also assessed the use of weighted robust algorithms to compensate the uneven expertise among the participating laboratories. METHODS: Three sets of coded images obtained through the dicentric chromosome assay from blood samples irradiated at 1.5 Gy (sample A) and 4 Gy (sample B), as well as a non-irradiated whole blood sample (sample C), were shared among LBDNet laboratories. The images were captured using the Metafer4 platform coupled with the AutoCapt module. The laboratories were requested to perform triage scoring, conventional scoring, and dose estimation. The dose estimation was carried out using either their laboratory calibration curve or a common calibration curve. A comparative statistical analysis was conducted using a weighted robust Hampel algorithm and z score to compensate for uneven expertise in dicentric analysis and dose assessment among all laboratories. RESULTS: Out of twelve laboratories, one had unsatisfactory estimated doses at 0 Gy, and two had unsatisfactory estimated doses at 1.5 Gy when using their own calibration curve and triage scoring mode. However, all doses were satisfactory at 4 Gy. Six laboratories had estimated doses within 95% uncertainty limits at 0 Gy, seven at 1.5 Gy, and four at 4 Gy. While the mean dose for sample C was significantly biased using robust algorithms, applying weights to compensate for the laboratory's analysis expertise reduced the bias by half. The bias from delivered doses was only notable for sample C. Using the common calibration curve for dose estimation reduced the standard deviation (s*) estimated by robust methods for all three samples. CONCLUSIONS: The results underscore the significance of performing interlaboratory comparison exercises that involve digitized and electronically transmitted images, even when analyzing non-irradiated samples. In situations where the participating laboratories possess different levels of proficiency, it may prove essential to employ weighted robust algorithms to achieve precise outcomes.


Assuntos
Aberrações Cromossômicas , Humanos , Aberrações Cromossômicas/efeitos da radiação , Algoritmos , Laboratórios/normas , Radiometria/métodos , Processamento de Imagem Assistida por Computador/métodos
15.
Eur J Nutr ; 52(4): 1343-51, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22923035

RESUMO

BACKGROUND AND AIMS: Protein malnutrition affects resistance to infection by impairing the inflammatory response, modifying the function of effector cells, such as macrophages. Recent studies have revealed that glutamine-a non-essential amino acid, which could become conditionally essential in some situations like trauma, infection, post-surgery and sepsis-is able to modulate the synthesis of cytokines. The aim of this study was to evaluate the effect of glutamine on the expression of proteins involved in the nuclear factor-kappa B (NF-κB) signalling pathway of peritoneal macrophages from malnourished mice. METHODS: Two-month-old male Balb/c mice were submitted to protein-energy malnutrition (n = 10) with a low-protein diet containing 2 % protein, whereas control mice (n = 10) were fed a 12 % protein-containing diet. The haemogram and analysis of plasma glutamine and corticosterone were evaluated. Peritoneal macrophages were pre-treated in vitro with glutamine (0, 0.6, 2 and 10 mmol/L) for 24 h and then stimulated with 1.25 µg LPS for 30 min, and the synthesis of TNF-α and IL-1α and the expression of proteins related to the NF-κB pathway were evaluated. RESULTS: Malnourished animals had anaemia, leucopoenia, lower plasma glutamine and increased corticosterone levels. TNF-α production of macrophages stimulated with LPS was significantly lower in cells from malnourished animals when cultivated in supraphysiological (2 and 10 mmol/L) concentrations of glutamine. Further, glutamine has a dose-dependent effect on the activation of macrophages, in both groups, when stimulated with LPS, inducing a decrease in TNF-α and IL-1α production and negatively modulating the NF-κB signalling pathway. CONCLUSIONS: These data lead us to infer that the protein malnutrition state interferes with the activation of macrophages and that higher glutamine concentrations, in vitro, have the capacity to act negatively in the NF-κB signalling pathway.


Assuntos
Modelos Animais de Doenças , Regulação para Baixo , Glutamina/metabolismo , Macrófagos Peritoneais/imunologia , NF-kappa B/metabolismo , Desnutrição Proteico-Calórica/imunologia , Transdução de Sinais , Animais , Animais não Endogâmicos , Células Cultivadas , Corticosterona/sangue , Suplementos Nutricionais , Glutamina/sangue , Imunomodulação , Interleucina-1alfa/metabolismo , Ativação de Macrófagos , Macrófagos Peritoneais/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Fosforilação , Processamento de Proteína Pós-Traducional , Desnutrição Proteico-Calórica/sangue , Desnutrição Proteico-Calórica/metabolismo
16.
J Trace Elem Med Biol ; 80: 127290, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37659124

RESUMO

The bone marrow is responsible for producing an incredible number of cells daily in order to maintain blood homeostasis through a process called hematopoiesis. Hematopoiesis is a greatly demanding process and one entirely dependent on complex interactions between the hematopoietic stem cell (HSC) and its surrounding microenvironment. Zinc (Zn2+) is considered an important trace element, playing diverse roles in different tissues and cell types, and zinc finger proteins (ZNF) are proteins that use Zn2+ as a structural cofactor. In this way, the ZNF structure is supported by a Zn2+ that coordinates many possible combinations of cysteine and histidine, with the most common ZNF being of the Cys2His2 (C2H2) type, which forms a family of transcriptional activators that play an important role in different cellular processes such as development, differentiation, and suppression, all of these being essential processes for an adequate hematopoiesis. This review aims to shed light on the relationship between ZNF and the regulation of the hematopoietic tissue. We include works with different designs, including both in vitro and in vivo studies, detailing how ZNF might regulate hematopoiesis.


Assuntos
Fatores de Transcrição , Dedos de Zinco , Fatores de Transcrição/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Hematopoese , Medula Óssea
17.
Nutr Rev ; 2023 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-37717139

RESUMO

There has been a global increase in the older population in recent decades and, as age advances, complex metabolic and epigenetic changes occur in the organism, and these may trigger some health complications commonly found among this population. Additionally, several changes occur in older people that can reduce the dietary intake or the process of nutrient absorption. In this way, tissues with high nutrient requirements are more affected. Hematopoiesis is the process of formation, development, and maturation of blood cells and is a process with a high turnover. This high demand makes the integrity of the hematopoietic process susceptible to various factors that impair physiological function, such as aging and micronutrient bioavailability. Among these micronutrients, Zinc is considered an important micronutrient, playing diverse roles across various tissues and cell types. Some of the alterations in hematopoiesis that appear as a consequence of aging and due to insufficient micronutrient intake are well described in the literature; however, not much is known about how zinc deficiency contributes towards the development of diseases seen in aging. Considering the importance of zinc to act on several biological processes, this narrative review discusses several studies related to the physiological requirements, deficiency, or excess of zinc, including studies in experimental models and humans, and aimed to shed light on the relationship between zinc and the regulation of hematopoietic tissue, exploring possible links between this mineral with common disorders that appear during aging.

18.
Braz J Microbiol ; 54(2): 1047-1054, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36811770

RESUMO

Measuring microbial inactivation in food is useful for food technology as it allows for predicting the growth or death of microorganisms. This study aimed to investigate the effect of gamma irradiation on the lethality of microorganisms inoculated in milk, estimate the mathematical model of inactivation of each microorganism, and evaluate kinetic indices to determine the efficient dose in the treatment of milk. Raw milk samples were inoculated with cultures of Salmonella enterica subsp. enterica serovar Enteritidis (ATCC 13076), Escherichia coli (ATCC 8739), and Listeria innocua (ATCC 3309), irradiated at doses of 0, 0.5, 1, 1.5, 2, 2.5, and 3 kGy. The fitting of the models to the microbial inactivation data was performed using the GinaFIT software. The results demonstrated a significant effect of irradiation doses on the population of microorganisms, with the application of a dose of 3 kGy, a reduction of approximately 6 logarithmic cycles is observed for L. innocua and 5 for S. Enteritidis and E. coli. The model with the best fit was different for each microorganism studied: for L. innocua, the model was log-linear + shoulder; for S. Enteritidis and E. coli, the model that showed the best fit was the biphasic. The studied model fitted well (R2 ≥ 0.9; R2 adj. ≥ 0.9 and smallest RMSE values) for the inactivation kinetics. The lethality of the treatment, considering a reduction in the 4D value, was achieved with the predicted dose of doses of ±2.22, ±2.10, and ±1.77 kGy, for L. innocua, S. Enteritidis, and E. coli, respectively.


Assuntos
Listeria monocytogenes , Listeria , Animais , Escherichia coli , Salmonella enteritidis , Leite/microbiologia , Contagem de Colônia Microbiana , Microbiologia de Alimentos
19.
Polymers (Basel) ; 15(3)2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36772062

RESUMO

This work aimed to use the electrospinning technique to obtain PBAT/PLA polymer fibers, with the semiconductors rutile titanium dioxide (TiO2-R) and magnetite iron oxide (Fe3O4), in order to promote the photocatalytic degradation of environmental contaminants. The parameters used in the electrospinning process to obtain the fibers were distance from the needle to the collecting target of 12 cm, flow of 1 mL h-1 and voltage of 14 kV. The best mass ratio of semiconductors in the polymeric fiber was defined from a 22 experimental design, and the values obtained were 10% TiO2-R, 1% Fe3O4 at pH 7.0. Polymer fibers were characterized by Scanning Electron Microscopy (SEM), Differential Scanning Calorimetry (DSC), X-ray Diffraction (XRD), Thermogravimetric Analysis (TGA) and Fourier Transform Infrared (FTIR) techniques. SEM measurements indicated a reduction in fiber diameter after the incorporation of semiconductors; for the PBAT/PLA fiber, the average diameter was 0.9466 ± 0.2490 µm, and for the fiber with TiO2-R and Fe3O4 was 0.6706 ± 0.1447 µm. In the DSC, DRX, TGA and FTIR analyses, it was possible to identify the presence of TiO2-R and Fe3O4 in the fibers, as well as their interactions with polymers, demonstrating changes in the crystallinity and degradation temperature of the material. These fibers were tested against Reactive Red 195 dye, showing an efficiency of 64.0% within 24 h, showing promise for photocatalytic degradation of environmental contaminants.

20.
Neurogastroenterol Motil ; 35(12): e14688, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37831748

RESUMO

AIMS: Our main goals were to investigate the effects of L-glutathione (1%) treatment in Walker-256 tumor-bearing rats by analyzing immunoreactive neurons (IR), responsive to the nNOS enzyme and 3-Nitrotyrosine, in their jejunum myenteric plexus. Moreover, the oxidative state and inflammatory process in these animals were investigated. METHODS: Four experimental groups were utilized: control (C), control treated with L-glutathione (CGT), Walker-256 tumor-bearing rats (TW), and Walker-256 tumor-bearing rats treated with L-glutathione (TWGT). After 14 days of tumor inoculation, the jejunum was collected for immunohistochemical techniques and assessment of oxidative status. Plasma was collected to evaluate oxidative status and measure cytokines. RESULTS: The TW group exhibited a decrease of reduced glutathione in their jejunum, which was prevented in the L-glutathione treated TWGT group. TW animals presented pronounced oxidative stress by increasing levels of lipoperoxidation in their jejunum and malondialdehyde in their plasma; however, the L-glutathione treatment in TWGT group was not able to avoid it. The total antioxidant capacity was altered in groups TW and TWGT, yet the last one had a better index in their plasma. The IL-10, and TNF-α levels increased in TWGT animals. The nNOS-IR neuron density decreased in the jejunum myenteric plexus of the TW group, which was avoided in the TWGT group. The nNOS +3-Nitrotyrosine neurons quantification did not show significative alterations. CONCLUSION: The treatment with L-glutathione (1%) imposed an important defense to some parameters of oxidative stress induced by TW-256, leading to neuroprotection to the loss in the nNOS-IR neuron density.


Assuntos
Neoplasias , Neurônios Nitrérgicos , Ratos , Animais , Jejuno , Ratos Wistar , Neuroproteção , Estresse Oxidativo , Glutationa/metabolismo , Plexo Mientérico/patologia , Neoplasias/metabolismo , Neoplasias/patologia
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