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1.
Poult Sci ; 103(6): 103640, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38688195

RESUMO

The transmission electron microscopy revealed a dendritic cell in the medulla of the chicken bursal follicle. This dendritic cell has a classical secretory machinery; therefore, it has been named a bursal secretory dendritic cell (BSDC). The corticomedullary epithelial arch (CMEA) encloses lymphoid-like cells, which can proliferate and after entering the medulla, begin to differentiate to immature, then mature BSDC, which discharges glycoprotein (gp). With the exhaustion of gp production, the BSDC rapidly transforms into a macrophage-like cell (Mal), which is an activated endocytic cell of innate immunity. The Mal drifts through the follicle-associated epithelium (FAE)-supporting cells into the FAE, and via FAE, the Mal is eliminated in the bursal lumen. The infectious bursal disease virus (IBDV) infection accelerates the maturation process of BSDC precursors, which results in acute emptying of CMEA and subsequently, numerous immature BSDC(s) emerge. The IBDV infection stops the gp discharge, and the gp appears in the virus-containing Mal. The Movat pentachrome staining recognizes the gp in the extracellular spaces of the medulla and after infection in the Mal. The BSDC is the primary target of the IBDV. During IBDV infection, a large number of suddenly formed Mal actively migrate into the cortex, initiating cytokine storm and recruiting heterophil granulocytes. During embryogenesis, the vimentin-positive, possibly embryonic dendritic cells provide a microenvironment for carbohydrate switch. Around hatching, these embryonic, temporary dendritic cells get the Fc receptor, which bind maternal IgY. The posthatched forms of BSDC(s) gradually replace the embryonic ones and bind their own IgY.

2.
Viruses ; 15(6)2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-37376601

RESUMO

There are two types of secretory cells in the chicken bursa of Fabricius (BF): (a) interfollicular epithelial cells (IFE), and (b) bursal secretory dendritic cells (BSDC) in the medulla of bursal follicles. Both cells produce secretory granules, and the cells are highly susceptible to IBDV vaccination and infection. Before and during embryonic follicular bud formation, an electron-dense, scarlet-acid fuchsin positive substance emerges in the bursal lumen, the role of which is unknown. In IFE cells, IBDV infection may induce rapid granular discharge, and in several cells, peculiar granule formation, which suggests that the glycosylation of protein is injured in the Golgi complex. In control birds, the discharged BSDC granules appear in membrane-bound and subsequently solubilized, fine-flocculated forms. The solubilized, fine-flocculated substance is Movat-positive and can be a component of the medullary microenvironment, which prevents the medullary B lymphocytes from nascent apoptosis. Vaccination interferes with the solubilization of the membrane-bound substance, resulting in: (i) aggregation of a secreted substance around the BSDC, and (ii) solid lumps in the depleted medulla. The non-solubilized substance is possibly not "available" for B lymphocytes, resulting in apoptosis and immunosuppression. In IBDV infection, one part of the Movat-positive Mals fuse together to form a medullary, gp-containing "cyst". The other part of Mals migrate into the cortex, recruiting granulocytes and initiating inflammation. During recovery the Movat-positive substance appears as solid, extracellular lumps between the cells of FAE and Mals. Possibly the Mals and Movat-positive extracellular lumps glide into the bursal lumen via FAE to eliminate cell detritus from the medulla.


Assuntos
Infecções por Birnaviridae , Vírus da Doença Infecciosa da Bursa , Doenças das Aves Domésticas , Vacinas , Animais , Galinhas , Linfócitos B , Bolsa de Fabricius , Glicoproteínas , Infecções por Birnaviridae/veterinária
3.
Cells ; 11(23)2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36497119

RESUMO

KCC2 mediates extrusion of K+ and Cl- and assuresthe developmental "switch" in GABA function during neuronal maturation. However, the molecular mechanisms underlying KCC2 regulation are not fully elucidated. We investigated the impact of transforming growth factor beta 2 (TGF-ß2) on KCC2 during neuronal maturation using quantitative RT-PCR, immunoblotting, immunofluorescence and chromatin immunoprecipitation in primary mouse hippocampal neurons and brain tissue from Tgf-ß2-deficient mice. Inhibition of TGF-ß/activin signaling downregulates Kcc2 transcript in immature neurons. In the forebrain of Tgf-ß2-/- mice, expression of Kcc2, transcription factor Ap2ß and KCC2 protein is downregulated. AP2ß binds to Kcc2 promoter, a binding absent in Tgf-ß2-/-. In hindbrain/brainstem tissue of Tgf-ß2-/- mice, KCC2 phosphorylation at T1007 is increased and approximately half of pre-Bötzinger-complex neurons lack membrane KCC2 phenotypes rescued through exogenous TGF-ß2. These results demonstrate that TGF-ß2 regulates KCC2 transcription in immature neurons, possibly acting upstream of AP2ß, and contributes to the developmental dephosphorylation of KCC2 at T1007. The present work suggests multiple and divergent roles for TGF-ß2 on KCC2 during neuronal maturation and provides novel mechanistic insights for TGF-ß2-mediated regulation of KCC2 gene expression, posttranslational modification and surface expression. We propose TGF-ß2 as a major regulator of KCC2 with putative implications for pathophysiological conditions.


Assuntos
Células-Tronco Neurais , Simportadores , Fator de Crescimento Transformador beta2 , Animais , Camundongos , Hipocampo/citologia , Hipocampo/metabolismo , Células-Tronco Neurais/metabolismo , Neurônios/metabolismo , Fosforilação , Fator de Crescimento Transformador beta2/metabolismo , Simportadores/metabolismo , Cotransportadores de K e Cl-
4.
Viruses ; 14(8)2022 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-36016310

RESUMO

The aim of this study is to follow the gp production in IBDV-vaccinated and challenged birds. The progress of IBDV infection was monitored using anti-VP2 immunocytochemistry, light and transmission electron microscopy. In the medulla of the bursal follicle, the Movat pentachrome staining discovered an extracellular glycoprotein (gp) produced by bursal secretory dendritic cells (BSDCs). The secretory granules of BSDCs either discharge resulting in extracellular gp or fuse together forming intracellular corpuscles. The double fate of granules suggests a dual function of BSDCs: (a.) For the discharged granules, gp contributes to the medullary microenvironment (ME). (b.) The intracellular corpuscles may be the sign of BSDC transformation to a macrophage-like cell (Mal). Infectious bursal disease virus (IBDV) infection accelerates the BSDC transformation to Mal. The decreased number of BSDCs is feedback for the precursor cells of BSDCs lodging in the cortico-medullary epithelial arches (CMEA), where they proliferate. Opening the CMEA, the precursor cells enter the medulla, and differentiate to immature BSDCs. The virus uptake in the corpuscles prevents the granular discharge resulting in the absence of gp and alteration in ME. In vaccine-take birds, the mitotic rate of BSDC precursor cells cannot restore the precursor pool; therefore, in the case of IBDV challenge, the number of newly formed BSDCs is too low for outbreak of clinical disease. The BSDCs, as a primary target of IBDV, may contribute to the long-lasting immunosuppressive status of IBDV-infected chickens.


Assuntos
Infecções por Birnaviridae , Vírus da Doença Infecciosa da Bursa , Doenças das Aves Domésticas , Vacinas Virais , Animais , Anticorpos Antivirais , Infecções por Birnaviridae/veterinária , Bolsa de Fabricius , Galinhas , Células Dendríticas , Glicoproteínas
5.
Poult Sci ; 101(4): 101727, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35172235

RESUMO

The bursal secretory dendritic cell (BSDC) was discovered more than 40 yr ago. It is a highly polarized, granulated cell, locating in the medulla of bursal follicle. The cytoplasmic granules either discharge or fuse together forming large, irregular-shaped, dense bodies. Formation of the dense bodies could be the first sign of BSDC transformation to macrophage-like cell (Mal) which is the result of terminal maturation of BSDC. The BSDC is non-phagocytic, unlike Mal. The discharged substance may be attached to the cell membrane (membrane-bound form) and after detaching, appears as a flocculated substance in the extracellular space of medulla. Movat pentachrome staining shows, that this substance is a glycoprotein (gp), which may be contributed to the microenvironment of the medulla. Medullary lymphocytes are floating in the gp. Precursors of the BSDC locate in the corticomedullary epithelial arches, which operate under the effect of Notch/Serrate signaling. The Notch signaling determines the fate of lymphoblast-like precursor cells and inhibits the appearance of immunoglobulin heavy chain. In the arches, the precursor cells proliferate and entering the medulla differentiate. The dense bodies pack the virus particles, which prevents the granular discharge, resulting in disappearance of extracellular gp, but gp emerges inside the virus containing Mal. In infected birds, the Mal contains either apoptotic cells or virus particles. If vaccination or infectious bursal disease virus (IBDV) infection use up the BSDC precursors, the recovery of follicle is critical.


Assuntos
Infecções por Birnaviridae , Vírus da Doença Infecciosa da Bursa , Doenças das Aves Domésticas , Animais , Infecções por Birnaviridae/veterinária , Bolsa de Fabricius , Galinhas , Células Dendríticas , Glicoproteínas , Macrófagos
6.
Curr Issues Mol Biol ; 43(1): 79-92, 2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-34066967

RESUMO

BACKGROUND: Vitamin D deficiency (VDD) may be considered an independent cardiovascular (CV) risk factor, and it is well known that CV risk is higher in males. Our goal was to investigate the pharmacological reactivity and receptor expression of intramural coronary artery segments of male rats in cases of different vitamin D supply. METHODS: Four-week-old male Wistar rats were divided into a control group (n = 11) with optimal vitamin D supply (300 IU/kgbw/day) and a VDD group (n = 11, <0.5 IU/kgbw/day). After 8 weeks of treatment, intramural coronary artery segments were microprepared, their pharmacological reactivity was examined by in vitro microangiometry, and their receptor expression was investigated by immunohistochemistry. RESULTS: Thromboxane A2 (TXA2)-agonist induced reduced vasoconstriction, testosterone (T) and 17-ß-estradiol (E2) relaxations were significantly decreased, a significant decrease in thromboxane receptor (TP) expression was shown, and the reduction in estrogen receptor-α (ERα) expression was on the border of significance in the VDD group. CONCLUSIONS: VD-deficient male coronary arteries showed deteriorated pharmacological reactivity to TXA2 and sexual steroids (E2, T). Insufficient vasoconstrictor capacity was accompanied by decreased TP receptor expression, and vasodilator impairments were mainly functional. The decrease in vasoconstrictor and vasodilator responses results in narrowed adaptational range of coronaries, causing inadequate coronary perfusion that might contribute to the increased CV risk in VDD.


Assuntos
Arteríolas/patologia , Doença da Artéria Coronariana/patologia , Estradiol/farmacologia , Testosterona/farmacologia , Tromboxano A2/farmacologia , Deficiência de Vitamina D/complicações , Androgênios/farmacologia , Animais , Arteríolas/metabolismo , Doença da Artéria Coronariana/tratamento farmacológico , Doença da Artéria Coronariana/etiologia , Doença da Artéria Coronariana/metabolismo , Modelos Animais de Doenças , Estrogênios/farmacologia , Masculino , Ratos , Ratos Wistar , Receptores de Tromboxanos/metabolismo , Vasoconstrição , Deficiência de Vitamina D/metabolismo , Deficiência de Vitamina D/patologia
7.
Poult Sci ; 100(4): 101000, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33690054

RESUMO

In the medulla of bursal follicle, only the secretory dendritic cell (BSDC) is furnished with secretory machinery. The granular discharge of BSDC appears in membrane-bound and solubilized forms. Movat pentachrome staining proves that the solubilized form is a glycoprotein, which fills up the extracellular space of follicular medulla. The glycoprotein contributes to bursal microenvironment and may be attached to the surface of medullary lymphocytes. The secretory granules of BSDC may be fused, resulting in large, irregular dense bodies, which are the first sign of BSDC transformation to macrophage-like cells (Mal). To determine the effect of infectious bursal disease virus (IBDV) infection on the extracellular glycoprotein and BSDC, SPF chickens were experimentally infected with IBDV. On the surface of BSDC, the secretory substance is in high concentration, which may contribute to primary binding of IBDV to BSDC. The early distribution of IBDV infected cells is in consent with that BSDC. The IBDV infected BSDC rapidly transforms to Mal in which the glycoprotein staining appears. In the dense bodies, the packed virus particles inhibit the virus particles preventing the granular discharge, which may represent the first, early phase of virus replication cycle. The absence of extracellular glycoprotein results in alteration in the medullary microenvironment and subsequently B cell apoptosis. On the surface of medullary B cells, the solubilized secretory substance can be in much lower concentration, which results in secondary binding of IBDV to B cells. In secondary, late phase of virus replication cycle, the virus particles are not packed in electron dense substance which results in cytolytic lymphocytes and presence of virus in extracellular space. The Mal emigrates into the cortex, where induces inflammation, recruiting heterophil granulocyte and monocyte.


Assuntos
Infecções por Birnaviridae , Glicoproteínas , Vírus da Doença Infecciosa da Bursa , Doenças das Aves Domésticas , Animais , Infecções por Birnaviridae/fisiopatologia , Infecções por Birnaviridae/veterinária , Galinhas , Glicoproteínas/metabolismo , Vírus da Doença Infecciosa da Bursa/metabolismo , Linfócitos/patologia , Doenças das Aves Domésticas/fisiopatologia
8.
Antioxidants (Basel) ; 9(10)2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33076449

RESUMO

BACKGROUND: Several reports prove interconnection between vitamin D (VD) deficiency and increased cardiovascular risk. Our aim was to investigate the effects of VD status on biomechanical and oxidative-nitrative (O-N) stress parameters of coronary arterioles in rats. METHODS: 4-week-old male Wistar rats were divided into a control group (11 animals) with optimal VD supply (300 IU/kgbw/day) and a VD-deficient group (11 animals, <5 IU/kg/day). After 8 weeks, coronary arteriole segments were prepared. Geometrical, elastic, and biomechanical characteristics were measured by in vitro arteriography. O-N stress markers were investigated by immunohistochemistry. RESULTS: Inner radius decreased; wall thickness and wall-thickness/lumen diameter ratio increased; tangential wall stress and elastic modulus were reduced in VD-deficient group. No difference could be found in wall-cross-sectional area, intima-media area %. While the elastic elements of the vessel wall decreased, the α-smooth muscle actin (α-SMA) immunostaining intensity showed no changes. Significant elevation was found in the lipid peroxidation marker of 4-hidroxy-2-nonenal (HNE), while other O-N stress markers staining intensity (poly(ADP)ribose, 3-nitrotyrosine) did not change. CONCLUSIONS: Inward eutrophic remodeling has developed. The potential background of these impairments may involve the initial change in oxidative damage markers (HNE). These mechanisms can contribute to the increased incidence of the cardiovascular diseases in VD deficiency.

9.
PLoS One ; 14(5): e0216951, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31083690

RESUMO

Hyperandrogenism is a risk factor of cerebrovascular diseases as androgens can alter markedly the regulation of cerebrovascular tone. We examined the combined impact of androgen excess and vitamin D deficiency (VDD), a common co-morbidity in hyperandrogenic disorders, on remodeling and testosterone-induced vascular responses of anterior cerebral arteries (ACA) in order to evaluate the interplay between androgens and VDD in the cerebral vasculature. Male and female Wistar rats were either fed with vitamin D deficient or vitamin D supplemented diet. Half of the female animals from both groups received transdermal testosterone treatment. After 8 weeks, vessel lumen, wall thickness and testosterone-induced vascular tone of isolated ACA were determined using pressure microangiometry and histological examination. Androgen receptor protein expression in the wall of cerebral arteries was examined using immunohistochemistry. In female rats only combined VDD and testosterone treatment decreased the lumen and increased the wall thickness of ACA. In males, however VDD by itself was able to decrease the lumen and increase the wall thickness. Vascular reactivity showed similar alterations: in females, testosterone constricted the ACA only after combined VDD and hyperandrogenism, whereas in males VDD resulted in increased testosterone-induced contractions in spite of decreased androgen receptor expression. In conclusion, a marked interplay between hyperandrogenism and VDD results in inward remodeling and enhanced testosterone-induced constrictions of cerebral arteries, which might compromise the cerebral circulation and thus, increase the risk of stroke in the long term. In addition, the early cerebrovascular manifestation of VDD appears to require androgen excess and thus, depends on gender.


Assuntos
Androgênios/efeitos adversos , Hiperandrogenismo/fisiopatologia , Acidente Vascular Cerebral/fisiopatologia , Testosterona/efeitos adversos , Deficiência de Vitamina D/fisiopatologia , Administração Oral , Androgênios/administração & dosagem , Androgênios/sangue , Animais , Artéria Cerebral Anterior , Dieta , Modelos Animais de Doenças , Feminino , Expressão Gênica , Humanos , Hiperandrogenismo/sangue , Hiperandrogenismo/induzido quimicamente , Hiperandrogenismo/complicações , Masculino , Ratos , Ratos Wistar , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Risco , Fatores Sexuais , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/induzido quimicamente , Acidente Vascular Cerebral/etiologia , Testosterona/administração & dosagem , Testosterona/sangue , Vasoconstrição/efeitos dos fármacos , Vitamina D/administração & dosagem , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/induzido quimicamente , Deficiência de Vitamina D/complicações
10.
Artigo em Inglês | MEDLINE | ID: mdl-30774413

RESUMO

BACKGROUND: Acute kidney injury (AKI) is a serious complication after cardiac surgery that is associated with increased mortality and morbidity. Heme oxygenase-1 (HO-1) is an enzyme synthesized in renal tubular cells as one of the most intense responses to oxidant stress linked with protective, anti-inflammatory properties. Yet, it is unknown if serum HO-1 induction following cardiac surgical procedure involving cardiopulmonary bypass (CPB) is associated with incidence and severity of AKI. PATIENTS AND METHODS: In the present study, we used data from a prospective cohort study of 150 adult cardiac surgical patients. HO-1 measurements were performed before, immediately after and 24 hours post-CPB. In univariate and multivariate analyses, the association between HO-1 and AKI was investigated. RESULTS: AKI with an incidence of 23.3% (35 patients) was not associated with an early elevation of HO-1 after CPB in all patients (P=0.88), whereas patients suffering from AKI developed a second burst of HO-1 24 hours after CBP. In patients without AKI, the HO-1 concentrations dropped to baseline values (P=0.031). Furthermore, early HO-1 induction was associated with CPB time (P=0.046), while the ones 24 hours later lost this association (P=0.219). CONCLUSION: The association of the second HO-1 burst 24 hours after CBP might help to distinguish between the causality of AKI in patients undergoing CBP, thus helping to adapt patient stratification and management.

11.
Gynecol Endocrinol ; 35(6): 529-534, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30623742

RESUMO

Vitamin D (vitD) insufficiency affects 1 billion people worldwide. Androgen excess (AE) occurs in 8% of fertile females. There are few data about the combined effect of vitD deficiency and AE on the early biomechanical changes of cerebral arterioles in fertile-aged female. Forty-six adolescent female Wistar rats (21-28 day-old, weighing 90-110 g) were grouped randomly in four groups: vitD supplemented groups with and without transdermal testosterone (T) treatment, as well as vitD deficient groups also with and without transdermal T (n = 11 or 12, in all cases). After 8 weeks of treatment, anterior cerebral arterioles (in vivo diameter of 90-130 µm) were obtained and cylindrical segments were examined by pressure arteriography. Myogenic tone, tangential stress and incremental elastic moduli were computed and statistically analyzed. Elastic density was studied on resorcin-fuchsin-stained histological section. VitD deficiency with T treatment resulted in significantly lower inner radii and higher wall thickness values with reduced tangential stress and increased elastic fiber density. VitD deficiency reduced myogenic tone at higher intraluminar pressures (>110 mmHg). Our conclusion is that plasma vitD level is an important factor in the control of myogenic tone in cerebral resistance arteries. AE and vitD deficiency acting parallel induce remodeling of their wall.


Assuntos
Androgênios/farmacologia , Arteríolas/fisiopatologia , Colecalciferol/farmacologia , Testosterona/farmacologia , Remodelação Vascular/fisiologia , Deficiência de Vitamina D/fisiopatologia , Angiografia , Animais , Arteríolas/efeitos dos fármacos , Feminino , Ratos , Ratos Wistar , Remodelação Vascular/efeitos dos fármacos
12.
Microvasc Res ; 122: 78-84, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30502364

RESUMO

Vitamin D (VitD) hypovitaminosis and androgen excess (AE) are both risk factors for cardiovascular diseases in fertile women. However, the possible early interaction between AE and VitD status is not clear. Our goal was to describe how VitD status influences early changes in the biomechanical reactivity of small coronary arterioles in adult female rats after transdermal testosterone treatment. Forty-six adolescent, 90-110-gram-weighed female Wistar rats were randomly grouped into 4 groups. Twenty-four animals received an optimal VitD-supplemented diet, from which 12 animals underwent transdermal testosterone treatment. Twenty-two animals received a VitD-deficient diet, from which 11 were treated with testosterone. At 8 weeks of treatment, invasive arterial blood pressure was registered after in vivo cannulation of carotid artery. Arteriolar end and side branches (200 µm diameter) of the left anterior descendent coronary artery (LAD) were obtained and examined with pressure arteriography in vitro. Similar segments were removed for histological examination. The inner and outer radii of the arterioles were measured using video-microscopy. Normal myogenic tone, maximal passive vasorelaxation and vasoconstriction of the arterioles were measured and statistically analyzed. The vessels' maximal smooth muscle relaxant potential, thromboxane-induced contraction capacity and normal myogenic tone were significantly influenced by actual VitD status. A lower relaxation capacity and increased wall thickness were observed in VitD-deficient groups, which could cause rigidity of the coronary arterioles and elevate cardiovascular risk. Supplementation of VitD could improve myogenic tone and relaxation and hold cardiovascular benefits.


Assuntos
Arteríolas/fisiopatologia , Vasos Coronários/fisiopatologia , Tecido Elástico/fisiopatologia , Hiperandrogenismo/fisiopatologia , Vasoconstrição , Vasodilatação , Deficiência de Vitamina D/fisiopatologia , Animais , Arteríolas/efeitos dos fármacos , Arteríolas/patologia , Fenômenos Biomecânicos , Colecalciferol/farmacologia , Vasos Coronários/efeitos dos fármacos , Vasos Coronários/patologia , Modelos Animais de Doenças , Módulo de Elasticidade , Tecido Elástico/efeitos dos fármacos , Tecido Elástico/patologia , Feminino , Hiperandrogenismo/patologia , Ratos Wistar , Remodelação Vascular , Rigidez Vascular , Vasoconstrição/efeitos dos fármacos , Vasoconstritores/farmacologia , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia , Deficiência de Vitamina D/tratamento farmacológico , Deficiência de Vitamina D/patologia
13.
Diab Vasc Dis Res ; 15(4): 294-301, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29465004

RESUMO

Hyperandrogenic state in females is accompanied with metabolic syndrome, insulin resistance and vascular pathologies. A total of 67%-85% of hyperandrogenic women suffer also from vitamin D deficiency. We aimed to check a potential interplay between hyperandrogenism and vitamin D deficiency in producing insulin resistance and effects on coronary resistance arteries. Adolescent female rats were divided into four groups, 11-12 animals in each. Transdermal testosterone-treated and vehicle-treated animals were kept either on vitamin D-deficient or on vitamin D-supplemented diet for 8 weeks. Plasma sexual steroid, insulin, leptin and vitamin D plasma levels were measured, and oral glucose tolerance test was performed. In coronary arterioles, insulin receptor and vitamin D receptor expressions were tested by immunohistochemistry, and insulin-induced relaxation was measured in vitro on isolated coronary resistance artery segments. Testosterone impaired glucose tolerance, and it diminished insulin relaxation but did not affect the expression of insulin and vitamin D receptors in vascular tissue. Vitamin D deficiency elevated postprandial insulin levels and homeostatic model assessment insulin resistance. It also diminished insulin-induced coronary arteriole relaxation, while it raised the expression of vitamin D and insulin receptors in the endothelial and medial layers. Our conclusion is that both hyperandrogenism and vitamin D deficiency reduce sensitivity of coronary vascular tissue to insulin, but they do it with different mechanisms.


Assuntos
Arteríolas/fisiopatologia , Doença da Artéria Coronariana/etiologia , Vasos Coronários/fisiopatologia , Hiperandrogenismo/complicações , Resistência à Insulina , Síndrome do Ovário Policístico/complicações , Deficiência de Vitamina D/complicações , Animais , Arteríolas/metabolismo , Biomarcadores/sangue , Glicemia/metabolismo , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/fisiopatologia , Vasos Coronários/metabolismo , Modelos Animais de Doenças , Feminino , Teste de Tolerância a Glucose , Hormônios Esteroides Gonadais/sangue , Hiperandrogenismo/sangue , Hiperandrogenismo/fisiopatologia , Insulina/sangue , Leptina/sangue , Síndrome do Ovário Policístico/sangue , Síndrome do Ovário Policístico/fisiopatologia , Ratos Wistar , Fatores de Tempo , Resistência Vascular , Vasodilatação , Vitamina D/sangue , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/fisiopatologia
14.
BMC Nephrol ; 19(1): 34, 2018 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-29426301

RESUMO

BACKGROUND: The Catechol-O-methyltransferase (COMT) represents the key enzyme in catecholamine degradation. Recent studies suggest that the COMT rs4680 polymorphism is associated with the response to endogenous and exogenous catecholamines. There are, however, conflicting data regarding the COMT Met/Met phenotype being associated with an increased risk of acute kidney injury (AKI) after cardiac surgery. The aim of the current study is to prospectively investigate the impact of the COMT rs4680 polymorphism on the incidence of AKI in patients undergoing cardiac surgery. METHODS: In this prospective single center cohort study consecutive patients hospitalized for elective cardiac surgery including cardiopulmonary-bypass (CPB) were screened for participation. Demographic clinical data, blood, urine and tissue samples were collected at predefined time points throughout the clinical stay. AKI was defined according to recent recommendations of the Kidney Disease Improving Global Outcome (KDIGO) group. Genetic analysis was performed after patient enrolment was completed. RESULTS: Between April and December 2014, 150 patients were recruited. The COMT genotypes were distributed as follows: Val/Met 48.7%, Met/Met 29.3%, Val/Val 21.3%. No significant differences were found for demography, comorbidities, or operative strategy according to the underlying COMT genotype. AKI occurred in 35 patients (23.5%) of the total cohort, and no differences were evident between the COMT genotypes (20.5% Met/Met, 24.7% Val/Met, 25.0% Val/Val, p = 0.66). There were also no differences in the post-operative period, including ICU or in-hospital stay. CONCLUSIONS: We did not find statistically significant variations in the risk for postoperative AKI, length of ICU or in-hospital stay according to the underlying COMT genotype.


Assuntos
Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/genética , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Catecol O-Metiltransferase/genética , Polimorfismo de Nucleotídeo Único/genética , Injúria Renal Aguda/diagnóstico , Idoso , Procedimentos Cirúrgicos Cardíacos/tendências , Estudos de Coortes , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/genética , Estudos Prospectivos
15.
PLoS One ; 13(2): e0192480, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29408903

RESUMO

BACKGROUND AND PURPOSE: Vitamin D deficiency (VDD) is a global health problem, which can lead to several pathophysiological consequences including cardiovascular diseases. Its impact on the cerebrovascular system is not well understood. The goal of the present work was to examine the effects of VDD on the morphological, biomechanical and functional properties of cerebral arterioles. METHODS: Four-week-old male Wistar rats (n = 11 per group) were either fed with vitamin D deficient diet or received conventional rat chow with per os vitamin D supplementation. Cardiovascular parameters and hormone levels (testosterone, androstenedione, progesterone and 25-hydroxyvitamin D) were measured during the study. After 8 weeks of treatment anterior cerebral artery segments were prepared and their morphological, biomechanical and functional properties were examined using pressure microangiometry. Resorcin-fuchsin and smooth muscle actin staining were used to detect elastic fiber density and smooth muscle cell counts in the vessel wall, respectively. Sections were immunostained for eNOS and COX-2 as well. RESULTS: VDD markedly increased the wall thickness, the wall-to-lumen ratio and the wall cross-sectional area of arterioles as well as the number of smooth muscle cells in the tunica media. As a consequence, tangential wall stress was significantly lower in the VDD group. In addition, VDD increased the myogenic as well as the uridine 5'-triphosphate-induced tone and impaired bradykinin-induced relaxation. Decreased eNOS and increased COX-2 expression were also observed in the endothelium of VDD animals. CONCLUSIONS: VDD causes inward hypertrophic remodeling due to vascular smooth muscle cell proliferation and enhances the vessel tone probably because of increased vasoconstrictor prostanoid levels in young adult rats. In addition, the decreased eNOS expression results in endothelial dysfunction. These morphological and functional alterations can potentially compromise the cerebral circulation and lead to cerebrovascular disorders in VDD.


Assuntos
Arteríolas/fisiopatologia , Artérias Cerebrais/fisiopatologia , Remodelação Vascular , Deficiência de Vitamina D/fisiopatologia , Animais , Glicemia/metabolismo , Masculino , Ratos , Ratos Wistar , Vitamina D/análogos & derivados , Vitamina D/sangue
16.
J Morphol ; 279(1): 17-26, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28914464

RESUMO

The surface epithelium of the bursa of Fabricius consists of interfollicular (IFE) and follicle-associated epithelium (FAE). The IFE comprises (i) cylindrical-shaped secretory cells (SC) and (ii) cuboidal basal cells (BCs). The FAE provides histological and two-way functional connections between the bursal lumen and medulla of the follicle. We used a carbon solution and anti-caveolin-1 (Cav-1) to study the endocytic activity of FAE. Carbon particles entered the intercellular space of FAE, but the carbon particles were not internalized by the FAE cells. Cav-1 was not detectable in the FAE cells or the medulla of the bursal follicle. The absence of Cav-1 indicates that no caveolin-mediated endocytosis occurs in the FAE cells, B cells, bursal secretory dendritic cells (BSDC), or reticular epithelial cells. Surprisingly, a significant number of Cav-1 positive cells can be found among the SC, which are designated SC II. Cav-1 negative cell are called SC I, and they produce mucin for lubricating the bursal lumen and duct. Occasionally, BCs also express Cav-1, which suggests that BC is a precursor of a SC. Transmission electron microscopy confirmed the existence of type I and II SC. The SC II are highly polarized and have an extensive trans-Golgi network that is rich in different granules and vesicles. Western blot analysis of bursa lysates revealed a 21-23 kDa compound (caveolin) and Filipin fluorescence histochemistry provided evidence for intracellular cholesterol. High amount of cholesterol in the feces shows the cholesterol efflux from SC II. The presence of Cav-1 and cholesterol in SC II indicates, that the bursa is a complex organ in addition to possessing immunological function contributes to the cholesterol homeostasis in the chickens.


Assuntos
Bolsa de Fabricius/metabolismo , Caveolina 1/metabolismo , Galinhas/metabolismo , Células Epiteliais/metabolismo , Epitélio/metabolismo , Animais , Bolsa de Fabricius/ultraestrutura , Carbono/metabolismo , Colesterol/metabolismo , Células Epiteliais/ultraestrutura , Epitélio/ultraestrutura , Feminino , Histocitoquímica , Masculino , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Modelos Biológicos
17.
Kidney Blood Press Res ; 42(3): 456-467, 2017 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-28750409

RESUMO

BACKGROUND/AIMS: Acute kidney injury (AKI) is a postoperative complication after cardiac surgery with a high impact on mortality and morbidity. Nephrocheck® [TIMP-2*IGFBP7] determines markers of tubular stress, which occurs prior to tubular damage. It is unknown at which time-point [TIMP-2*IGFBP7] measurement should be performed to ideally predict AKI. We investigated the association of [TIMP-2*IGFBP7] at various time-points with the incidence of AKI in patients undergoing elective cardiac surgery including cardio-pulmonary bypass. METHODS: In a prospective cohort study, serial blood and urine samples were collected from 150 patients: pre-operative, at ICU-admission, 24h and 48h post-surgery. AKI was defined as Serum-Creatinine rise >0.3 mg/dl within 48hrs. Urinary [TIMP-2*IGFBP7] was measured at pre-operative, ICU-admission and 24h post-surgery; medical staff was kept blinded to these results. RESULTS: A total of 35 patients (23.5%) experienced AKI, with a higher incidence in those with high [TIMP-2*IGFBP7] values at ICU admission (57.1% vs. 10.1%, p<0.001). In logistic regression [TIMP-2*IGFBP7] at ICU admission was independently associated with the occurrence of AKI (Odds Ratio 11.83; p<0.001, C-statistic= 0.74) after adjustment for EuroSCORE II and CBP-time. CONCLUSIONS: Early detection of elevated [TIMP-2*IGFBP7] at ICU admission was strongly predictive for postoperative AKI and appeared to be more precise as compared to subsequent measurements.

18.
J Mol Histol ; 42(6): 523-33, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21938483

RESUMO

Numerous biochemical and morphological studies have provided insight into the distribution pattern of caveolin-1 and the presence of membrane rafts in the vertebrate retina. To date however, studies have not addressed the localization profile of raft specific proteins during development. Therefore the purpose of our studies was to follow the localization pattern of caveolin-1, phospho-caveolin-1 and c-src in the developing retina and compare it to that observed in adults. Specific antibodies were used to visualize the distribution of caveolin-1, c-src, a kinase phosphorylating caveolin-1, and phospho-caveolin-1. The labeling pattern of this scaffolded complex was compared to those of rhodopsin and rhodopsin kinase. Samples were analyzed at various time points during postnatal development and compared to adult retinas. The immunocytochemical studies were complemented with immunoblots and immunoprecipitation studies. In the mature retina caveolin-1 and c-src localized mainly to the cell body and IS of photoreceptors, with only very weakly labeled OS. In contrast, phospho-caveolin-1 was only detectable in the OS of photoreceptors. During development we followed the expression and distribution profile of these proteins in a temporal sequence with special attention to the period when OS formation is most robust. Double labeling immunocytochemistry and immunoprecipitation showed rhodopsin to colocalize and co-immunoprecipitate with caveolin-1 and c-src. Individual punctate structures between the outer limiting membrane and the outer plexiform layer were seen at P10 to be labeled by both rhodopsin and caveolin-1 as well as by rhodopsin and c-src, respectively. These studies suggest that membrane raft specific proteins are co-distributed during development, thereby pointing to a role for such complexes in OS formation. In addition, the presence of small punctate structures containing caveolin-1, c-src and rhodopsin raise the possibility that these proteins may transport together to OS during development and that caveolin-1 exists predominantly in a phosphorylated form in the OS.


Assuntos
Caveolina 1/metabolismo , Células Fotorreceptoras/metabolismo , Proteínas Tirosina Quinases/metabolismo , Retina/metabolismo , Rodopsina/metabolismo , Animais , Proteína Tirosina Quinase CSK , Caveolina 1/genética , Diferenciação Celular/fisiologia , Cricetinae , Receptor Quinase 1 Acoplada a Proteína G/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Fosforilação/fisiologia , Proteínas Tirosina Quinases/genética , Retina/citologia , Retina/crescimento & desenvolvimento , Quinases da Família src
19.
Rev Sci Instrum ; 80(10): 104706, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19895084

RESUMO

Convective, hot air drying by itself is relatively efficient for removing water from the surface environment of agricultural seed products. However, moving internal moisture to the surface needs rather a long time, as a rule. The major research aim of the authors was to decrease the processing time and processing costs, to improve the quality of the dried product, and to increase drying efficiency. For this reason their research activities focused on the development of a special drying apparatus and a method suitable for measuring of energy conditions in a hybrid (microwave and convective) dryer. Experimental investigations were made with moistened wheat as model material. Experiments were carried out in microwave, convective and hybrid drying systems. The microwave drying alone was more efficient than the convective method. The lowest energy consumption and shortest drying time were obtained by the use of a hybrid method in which the waste energy of magnetron was utilized and the temperature was controlled. In this way, it was possible to keep the temperature of the dried product at a constant and safe value and to considerably decrease the energy consumption.


Assuntos
Dessecação/instrumentação , Dessecação/métodos , Micro-Ondas , Ar , Fontes de Energia Elétrica , Temperatura
20.
Horm Behav ; 52(5): 621-30, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17900575

RESUMO

According to some researchers, animals show different coping styles to deal with stressful situations. In the case of social carnivores, social stress is a substantial part of the overall stress load. Previous research has established two extreme (proactive and reactive) coping styles in several animal species, but means of coping with social stress has not yet been investigated in the case of dogs. The aim of this current study was to examine whether (1) experienced working police dogs adopt different coping strategies during a short-term unexpected social challenge presented by a threatening human, (2) whether this affects post-encounter cortisol levels, and (3) whether there is an association between the cortisol response and the behavior (coping strategy) displayed during the threatening approach. Using factor analysis, we have identified three different group of dogs which were characterized by either fearfulness, aggressiveness, or ambivalence and in parallel showed specific differences in their reaction norm when threatened by an approaching stranger. This grouping also allowed to draw possible parallels between aggressiveness and the proactive behavior style and fearfulness and reactive coping style, respectively. In addition, we have revealed a third group of animals which show ambivalent behavior in a social threatening situation.


Assuntos
Adaptação Psicológica/fisiologia , Comportamento Animal/fisiologia , Cães/fisiologia , Polícia , Estresse Psicológico/fisiopatologia , Fatores Etários , Algoritmos , Animais , Dominação-Subordinação , Medo/fisiologia , Humanos , Hidrocortisona/análise , Masculino , Saliva/química , Fatores de Tempo
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